Home > Products > State Listing > Oregon Data
Latest:
 AFDPQR |  AFDPDT |  AFDBOI |  AFDMFR |
  [top]

000
FXUS66 KPDT 180407
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
807 PM PST WED DEC 17 2014

.UPDATE...A FEW DISORGANIZED SHOWERS ARE MOVING ACROSS THE CWA
THIS EVENING. DENSE FOG IS OVER PARTS OF THE BLUE MOUNTAIN
FOOTHILLS. PATCHY FOG HAS DEVELOPED OVER THE KITTITAS VALLEY. WEB
CAMS AND OBSERVATIONS DO NOT SHOW VERY MUCH FOG IN CENTRAL AND
NORTH CENTRAL OREGON YET. FORECAST IS ON TRACK BUT WILL NEED TO
MONITOR DEVELOPMENT OF FOG WITH MOIST AND STAGNANT AIR MASS OVER
THE AREA.  COONFIELD

&&

.PREV DISC... /ISSUED 242 PM PST WED DEC 17 2014/

SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THURSDAY ORZ507-508.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THURSDAY WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76





000
FXUS66 KPDT 180407
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
807 PM PST WED DEC 17 2014

.UPDATE...A FEW DISORGANIZED SHOWERS ARE MOVING ACROSS THE CWA
THIS EVENING. DENSE FOG IS OVER PARTS OF THE BLUE MOUNTAIN
FOOTHILLS. PATCHY FOG HAS DEVELOPED OVER THE KITTITAS VALLEY. WEB
CAMS AND OBSERVATIONS DO NOT SHOW VERY MUCH FOG IN CENTRAL AND
NORTH CENTRAL OREGON YET. FORECAST IS ON TRACK BUT WILL NEED TO
MONITOR DEVELOPMENT OF FOG WITH MOIST AND STAGNANT AIR MASS OVER
THE AREA.  COONFIELD

&&

.PREV DISC... /ISSUED 242 PM PST WED DEC 17 2014/

SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THURSDAY ORZ507-508.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THURSDAY WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76





  [top]

000
FXUS65 KBOI 180355
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
855 PM MST WED DEC 17 2014

.DISCUSSION...THE MID LAYER TROUGH BROUGHT 0.02 INCHES OF PRECIP
TO BURNS AND A TRACE TO BAKER CITY AS OF 8 PM MST. CLOUD TOPS HAVE
WARMED THE LAST COUPLE HOURS AND RADAR ECHOES HAVE DIMINISHED. 00Z
GFS AND NAM BRING SOME LIGHT QPF ACROSS HARNEY/BAKER COUNTIES AND
EVEN LIGHTER AMTS TO CENTRAL IDAHO THROUGH 5 AM ASSOCIATED WITH A
SHEAR VORTICITY ALOFT. BEHIND THAT ANOTHER UPPER RIDGE IS
AMPLIFYING WHICH WILL PUSH THE SHEAR VORTICITY LOBE AND LIGHT QPF
ACROSS CENTRAL IDAHO THURSDAY. LOW QPF AND MIDLING POPS IN THE
FORECAST FAVORING OREGON THIS EVENING AND CENTRAL IDAHO THURSDAY
ARE ON TRACK WITH THIS. AREAS ABOVE 5K-6K FT WILL SEE TWO ROUNDS
OF SNOW...ONE LIGHT ONE FRIDAY AND A HEAVIER ONE SATURDAY NIGHT.
LOCALLY HEAVY SNOW IS EXPECTED SATURDAY NIGHT THROUGH EARLY
SUNDAY IN THE HIGHER MOUNTAINS.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS OVER HARNEY/BAKER COUNTIES AND CENTRAL IDAHO
WILL DECREASE OVER OREGON EARLY THURSDAY AND OVER IDAHO THURSDAY
EVENING. MOSTLY VFR THURSDAY NIGHT WITH PATCHY VALLEY FOG. SURFACE
WINDS...EAST TO SOUTH UP TO 10 KTS. WINDS ALOFT...SOUTHWEST 15
KTS UP THROUGH 10K FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....VM
PREV SHORT TERM...SP
PREV LONG TERM....JT/AB




000
FXUS65 KBOI 180355
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
855 PM MST WED DEC 17 2014

.DISCUSSION...THE MID LAYER TROUGH BROUGHT 0.02 INCHES OF PRECIP
TO BURNS AND A TRACE TO BAKER CITY AS OF 8 PM MST. CLOUD TOPS HAVE
WARMED THE LAST COUPLE HOURS AND RADAR ECHOES HAVE DIMINISHED. 00Z
GFS AND NAM BRING SOME LIGHT QPF ACROSS HARNEY/BAKER COUNTIES AND
EVEN LIGHTER AMTS TO CENTRAL IDAHO THROUGH 5 AM ASSOCIATED WITH A
SHEAR VORTICITY ALOFT. BEHIND THAT ANOTHER UPPER RIDGE IS
AMPLIFYING WHICH WILL PUSH THE SHEAR VORTICITY LOBE AND LIGHT QPF
ACROSS CENTRAL IDAHO THURSDAY. LOW QPF AND MIDLING POPS IN THE
FORECAST FAVORING OREGON THIS EVENING AND CENTRAL IDAHO THURSDAY
ARE ON TRACK WITH THIS. AREAS ABOVE 5K-6K FT WILL SEE TWO ROUNDS
OF SNOW...ONE LIGHT ONE FRIDAY AND A HEAVIER ONE SATURDAY NIGHT.
LOCALLY HEAVY SNOW IS EXPECTED SATURDAY NIGHT THROUGH EARLY
SUNDAY IN THE HIGHER MOUNTAINS.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS OVER HARNEY/BAKER COUNTIES AND CENTRAL IDAHO
WILL DECREASE OVER OREGON EARLY THURSDAY AND OVER IDAHO THURSDAY
EVENING. MOSTLY VFR THURSDAY NIGHT WITH PATCHY VALLEY FOG. SURFACE
WINDS...EAST TO SOUTH UP TO 10 KTS. WINDS ALOFT...SOUTHWEST 15
KTS UP THROUGH 10K FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....VM
PREV SHORT TERM...SP
PREV LONG TERM....JT/AB



000
FXUS65 KBOI 180355 CCA
AFDBOI

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE BOISE ID
855 PM MST WED DEC 17 2014

.DISCUSSION...THE MID LAYER TROUGH BROUGHT 0.02 INCHES OF PRECIP
TO BURNS AND A TRACE TO BAKER CITY AS OF 8 PM MST. CLOUD TOPS HAVE
WARMED THE LAST COUPLE HOURS AND RADAR ECHOES HAVE DIMINISHED. 00Z
GFS AND NAM BRING SOME LIGHT QPF ACROSS HARNEY/BAKER COUNTIES AND
EVEN LIGHTER AMTS TO CENTRAL IDAHO THROUGH 5 AM ASSOCIATED WITH A
SHEAR VORTICITY ALOFT. BEHIND THAT ANOTHER UPPER RIDGE IS
AMPLIFYING WHICH WILL PUSH THE SHEAR VORTICITY LOBE AND LIGHT QPF
ACROSS CENTRAL IDAHO THURSDAY. LOW QPF AND MIDLING POPS IN THE
FORECAST FAVORING OREGON THIS EVENING AND CENTRAL IDAHO THURSDAY
ARE ON TRACK WITH THIS. AREAS ABOVE 5K-6K FT WILL SEE TWO ROUNDS
OF SNOW...ONE LIGHT ONE FRIDAY AND A HEAVIER ONE SATURDAY NIGHT.
LOCALLY HEAVY SNOW IS EXPECTED SATURDAY NIGHT THROUGH EARLY
SUNDAY IN THE HIGHER MOUNTAINS.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS OVER HARNEY/BAKER COUNTIES AND CENTRAL IDAHO
WILL DECREASE OVER OREGON EARLY THURSDAY AND OVER IDAHO THURSDAY
EVENING. MOSTLY VFR THURSDAY NIGHT WITH PATCHY VALLEY FOG. SURFACE
WINDS...EAST TO SOUTH UP TO 10 KTS. WINDS ALOFT...SOUTHWEST 15
KTS UP THROUGH 10K FT MSL SHIFTING TO NW UP TO 15 KTS OVER OREGON
BY 12Z AND IDAHO BY 18Z THURSDAY.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....VM
PREV SHORT TERM...SP
PREV LONG TERM....JT/AB




000
FXUS65 KBOI 180355 CCA
AFDBOI

AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE BOISE ID
855 PM MST WED DEC 17 2014

.DISCUSSION...THE MID LAYER TROUGH BROUGHT 0.02 INCHES OF PRECIP
TO BURNS AND A TRACE TO BAKER CITY AS OF 8 PM MST. CLOUD TOPS HAVE
WARMED THE LAST COUPLE HOURS AND RADAR ECHOES HAVE DIMINISHED. 00Z
GFS AND NAM BRING SOME LIGHT QPF ACROSS HARNEY/BAKER COUNTIES AND
EVEN LIGHTER AMTS TO CENTRAL IDAHO THROUGH 5 AM ASSOCIATED WITH A
SHEAR VORTICITY ALOFT. BEHIND THAT ANOTHER UPPER RIDGE IS
AMPLIFYING WHICH WILL PUSH THE SHEAR VORTICITY LOBE AND LIGHT QPF
ACROSS CENTRAL IDAHO THURSDAY. LOW QPF AND MIDLING POPS IN THE
FORECAST FAVORING OREGON THIS EVENING AND CENTRAL IDAHO THURSDAY
ARE ON TRACK WITH THIS. AREAS ABOVE 5K-6K FT WILL SEE TWO ROUNDS
OF SNOW...ONE LIGHT ONE FRIDAY AND A HEAVIER ONE SATURDAY NIGHT.
LOCALLY HEAVY SNOW IS EXPECTED SATURDAY NIGHT THROUGH EARLY
SUNDAY IN THE HIGHER MOUNTAINS.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS OVER HARNEY/BAKER COUNTIES AND CENTRAL IDAHO
WILL DECREASE OVER OREGON EARLY THURSDAY AND OVER IDAHO THURSDAY
EVENING. MOSTLY VFR THURSDAY NIGHT WITH PATCHY VALLEY FOG. SURFACE
WINDS...EAST TO SOUTH UP TO 10 KTS. WINDS ALOFT...SOUTHWEST 15
KTS UP THROUGH 10K FT MSL SHIFTING TO NW UP TO 15 KTS OVER OREGON
BY 12Z AND IDAHO BY 18Z THURSDAY.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....VM
PREV SHORT TERM...SP
PREV LONG TERM....JT/AB


  [top]

000
FXUS66 KPQR 172252
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
252 PM PST WED DEC 17 2014

.SYNOPSIS...WEAK LOW PRESSURE WILL CROSS THE AREA THIS EVENING WITH
SHOWERS LINGERING OVERNIGHT. EXPECT FAIRLY QUIET WEATHER TO START
THE DAY THURSDAY. A MORE ORGANIZED FRONT WILL BRING GUSTY WINDS TO
THE COAST WITH RAIN SPREADING INLAND THURSDAY NIGHT AND FRIDAY.
RISING SNOW LEVELS WILL LIMIT SNOW TO THE HIGHEST PEAKS. COLDER AIR
BEHIND THE FRONT WILL BRING ACCUMULATING SNOW SHOWERS FOR THE
CASCADES PASSES FRIDAY EVENING AND SATURDAY. MILD AND VERY WET
WEATHER ARRIVED THIS WEEKEND. THERE IS POTENTIAL FOR AN ATMOSPHERIC
RIVER AND ASSOCIATED HEAVY RAIN TO DEVELOP OVER THE AREA AFFECTING
RIVERS INTO NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...A WEAK AND SPLITTING TROUGH
WILL SEND MOST OF ITS ENERGY SOUTH OF OUR AREA TONIGHT. WILL SEE
SHOWERS TAPER OFF OVERNIGHT AS HIGH PRESSURE BEGINS A TRANSIT ACROSS
THE AREA. WILL ALSO SEE CORRESPONDING SNOW LEVELS RISE ABOVE THE
PASSES AND GENERALLY LIMIT THE AMOUNT OF ACCUMULATIONS. THE RIDGE
AXIS QUICKLY PASSES EAST BY TOMORROW AFTERNOON LEADING TO A LARGELY
DRY DAY FOR THE INTERIOR.

ANOTHER MORE COHESIVE TROUGH AND FRONTAL SYSTEM WILL DIG OFFSHORE
WITH WARM FRONTAL RAIN TOUCHING THE COAST LATE FRIDAY AFTERNOON WITH
HEAVIER AMOUNTS BY EARLY FRIDAY EVENING. TIMING COULD BE EARLIER
DEPENDING ON MODEL OF CHOICE WITH THE GFS PERHAPS A COUPLE HOURS
FASTER THAN THE ECMWF AND THE NAM SLOWER YET. NAM TYPICALLY DOES NOT
HANDLE WARM PROCESS RAIN VERY WELL SO AM PUTTING LESS WEIGHT ON IT
TO START WITH. AS THE RAIN COMES IN...A COASTAL JET DEVELOPS
BRINGING FAIRLY GUSTY WINDS TO THE COAST AND COAST RANGE BUT NOTHING
TOO OUT OF THE ORDINARY. NOT ANTICIPATING ANY HIGHLIGHTS BUT
PROBABLY A RUN OF THE MILL WINDY COASTAL STORM. THE ASSOCIATED COLD
FRONT COME ASHORE AROUND 12Z FRIDAY MORNING AND CROSSES THE CASCADES
AROUND 17Z WITH COLDER AIR AND LOWERING SNOW LEVELS WITH AND MORE SO
BEHIND IT. PRECIPITATION TAPERS OFF AND BECOMES MORE SHOWERY IN
NATURE BEHIND THE FRONT. EXPECT LIGHT ACCUMULATING SNOW BEGINS AT
WILLAMETTE PASS AROUND DAY BREAK AND LOWERS TO NEAR GOVERNMENT PASS
LATER THAT MORNING. THE SNOW COMES TO BE TOO LITTLE...TOO LATE FOR
MUCH APPRECIABLE INCREASE IN THE SNOW PACK WITH PERHAPS A FEW INCHES
AT THE HIGHER PASSES AND LESS THAN AN INCH FOR GOVERNMENT CAMP.
HIGHER PEAKS COULD SEE UP TO A FOOT...HOWEVER. ANY OF THE MID
ELEVATION SNOW WILL BE RATHER SHORT-LIVED AS SNOW LEVELS IMMEDIATELY
BEGIN RISING IN ANTICIPATION OF THE PACIFIC STORM TRACK BECOMING
CENTERED OVER THE AREA.

MAIN ATTENTION THIS SHIFT HAS BEEN BE PLACED ON THE ATMOSPHERIC
RIVER EVENT SETTING UP TO AFFECT THE REGION THIS WEEKEND WITH
IMPACTS LASTING INTO NEXT WEEK. RAW GFS MODEL RUN ACCUMULATED QPF
AMOUNTS EXCEED 12 INCHES FOR PORTIONS OF THE CASCADES AND 10 INCHES
FOR THE COAST RANGE ENDING MONDAY MORNING. WILL SEE THE WARM RAINS
BEGIN AFFECTING THE COAST RANGE SATURDAY MORNING AND PUSH QUICKLY
INLAND TO THE CASCADES BY SATURDAY AFTERNOON. MOST OF THE HEAVY RAIN
OCCURS BEGINNING SATURDAY NIGHT. THERE WOULD BE DEEP WESTERLY FLOW
FROM THE SURFACE UP TO THE JET LEVEL THUS EXPECT THIS COULD BE AN
IDEAL OROGRAPHIC SITUATION TO EXTRACT A MAXIMUM AMOUNT OF RAIN FROM
WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE SUPPORT FROM THE
ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS FOLLOWING THE
HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT REALITY BRINGS
SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL RUNS STAY
UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM RIVERS
EXCEEDING FLOOD STAGE AS SOON AS SUNDAY EVENING.

HAVE ISSUED SOME OUTLOOK PRODUCTS TODAY LOOKING AHEAD TO FLOODING
POTENTIAL WITH THE CAVEAT THAT MODELS HAVE SHIFTED THE FOCUS FROM
NORTHERN WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA DURING THE
PAST 36 HOURS. ADDITIONAL SHIFTING IS EXPECTED AS WELL AS TIMING
DIFFERENCES. STAY TUNED AS THIS SITUATION EVOLVES OVER TIME.
/JBONK

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS MAINTAIN A
FLATTENED RIDGE OVER THE EASTERN PACIFIC FOR THE WEEKEND THROUGH
EARLY NEXT WEEK. WITH A NEARLY ZONAL JET AND ABUNDANT
MOISTURE...EXPECT PLENTY OF RAINFALL TO CONTINUE THROUGH SUNDAY. ON
MONDAY AND TUESDAY...SOME WEAK RIDGING MOVES OVER THE REGION BUT
SHOWERS LIKELY CONTINUE IN THE MOIST ONSHORE FLOW. AN UPPER TROUGH
DROPS SOUTH OVER THE REGION BY MIDWEEK WITH SOME RATHER COLD AIR AND
ADDITIONAL PRECIPITATION IN STORE. WHILE STILL SOME SIGNIFICANT
UNCERTAINTY EXISTS WITH RESPECT TO THE TIMING OF THE PRECIP VS COLD
AIR AND JUST HOW COLD THE AIR IS...IT DOES APPEAR THAT A SIGNIFICANT
SURGE OF COLD AIR MAY MOVE INTO THE REGION AND THEREFORE...DECREASED
TEMPERATURES ACCORDINGLY FOR THE TUE/WED PERIODS ACROSS THE REGION.
IT DOES APPEAR THAT SNOW LEVELS WILL DROP BELOW PASS LEVELS AT
LEAST...AND PERHAPS DOWN INTO THE FOOTHILL ELEVATIONS LATER
WEDNESDAY INTO THURSDAY. GIVEN THE UNCERTAINTY...THOSE PLANNING
HOLIDAY TRAVEL DURING THIS PERIOD SHOULD MONITOR THE FORECAST.
CULLEN

&&

.AVIATION...VFR CONDITIONS LIKELY TO CONTINUE THROUGH THIS
AFTERNOON. ONSHORE WINDS THIS EVENING BEHIND THE WEAK LOW MOVING
ONSHORE WILL ALLOW FOR CIGS AND VIS TO LOWER TO IFR TONIGHT WITH
THE DEVELOPMENT OF FOG/LOW STRATUS. THIS SHOULD HOLD ON THROUGH
THURSDAY MORNING...STARTING TO LIFT BACK TOWARD VFR AROUND 15 TO 18Z
THURSDAY AS WINDS START TO INCREASE OUT OF THE SOUTH. VFR WILL
CONTINUE THROUGH THURSDAY AFTERNOON...THOUGH LOW-LEVEL WIND SHEAR
WILL BE A CONCERN AT KTTD AND POSSIBLY KPDX AS 20 KT EASTERLY
WINDS FROM THE GORGE UNDERCUT INCREASING SOUTHERLY WINDS ALOFT.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST THIS
EVENING. WEAK WINDS WILL COULD PROMOTE THE DEVELOPMENT OF FOG/LOW
STRATUS AFTER 06Z THURSDAY...DROPPING CIGS AND VIS TO IFR. THIS
SHOULD LIFT BACK TO VFR BY 18Z THURSDAY. -MCCOY

&&

.MARINE...WEAK LOW PRESSURE SYSTEM MOVING NORTHWARD ALONG THE
COAST HAS BROUGHT WINDS UP TO SCA CRITERIA THIS AFTERNOON IN OUR
SOUTHERN WATERS. THIS IS WEAKENING AND MOVING ONSHORE...WHICH
SHOULD ALLOW WINDS TO SUBSIDE FOR A BRIEF PERIOD THIS EVENING.
WINDS WILL BEGIN TO INCREASE ACROSS OUR WATERS THURSDAY MORNING
AHEAD OF A COLD FRONT WHICH WILL MOVE THROUGH OUR WATERS DURING
THE DAY THURSDAY. AHEAD OF THIS FRONT...WINDS LIKELY TO RAMP UP TO
GALE FORCE WITH A COASTAL JET FULLY DEVELOPED BY THURSDAY
EVENING AND PERSIST UNTIL THE FRONT MOVES ONSHORE EARLY FRIDAY
MORNING.

SEAS CURRENTLY AROUND 10-12 FT WILL DROP TO 9 FT LATER THIS
EVENING. SEAS WILL BEGIN TO BUILD AGAIN THURSDAY MORNING AS WINDS
INCREASE AHEAD OF THE COLD FRONT ON THURSDAY. SEAS EXPECTED TO
BUILD TO THE LOW-TO-MIDDLE TEENS THURSDAY EVENING...SUBSIDING TO
10 TO 12 FT EARLY FRIDAY MORNING. A DYNAMIC FETCH APPROACHES EARLY
FRIDAY...BRINGING A LARGE SWELL INTO OUR WATERS. THIS WILL CAUSE
SEAS TO RAPIDLY BUILD FRIDAY MORNING...REACHING 20 FT FRIDAY
EVENING. THE NEXT STRONG FRONT APPROACHES ON SATURDAY...WITH
GALES POSSIBLE...COULD BUILD SEAS ALREADY 15 TO 20 FEET...TO 20
TO 25 FT SATURDAY. -MCCOY

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 4 AM TO 1 PM PST THURSDAY
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.

     GALE WARNING FROM 1 PM THURSDAY TO MIDNIGHT PST THURSDAY NIGHT
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THURSDAY FOR
     COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM PST THURSDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 172252
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
252 PM PST WED DEC 17 2014

.SYNOPSIS...WEAK LOW PRESSURE WILL CROSS THE AREA THIS EVENING WITH
SHOWERS LINGERING OVERNIGHT. EXPECT FAIRLY QUIET WEATHER TO START
THE DAY THURSDAY. A MORE ORGANIZED FRONT WILL BRING GUSTY WINDS TO
THE COAST WITH RAIN SPREADING INLAND THURSDAY NIGHT AND FRIDAY.
RISING SNOW LEVELS WILL LIMIT SNOW TO THE HIGHEST PEAKS. COLDER AIR
BEHIND THE FRONT WILL BRING ACCUMULATING SNOW SHOWERS FOR THE
CASCADES PASSES FRIDAY EVENING AND SATURDAY. MILD AND VERY WET
WEATHER ARRIVED THIS WEEKEND. THERE IS POTENTIAL FOR AN ATMOSPHERIC
RIVER AND ASSOCIATED HEAVY RAIN TO DEVELOP OVER THE AREA AFFECTING
RIVERS INTO NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...A WEAK AND SPLITTING TROUGH
WILL SEND MOST OF ITS ENERGY SOUTH OF OUR AREA TONIGHT. WILL SEE
SHOWERS TAPER OFF OVERNIGHT AS HIGH PRESSURE BEGINS A TRANSIT ACROSS
THE AREA. WILL ALSO SEE CORRESPONDING SNOW LEVELS RISE ABOVE THE
PASSES AND GENERALLY LIMIT THE AMOUNT OF ACCUMULATIONS. THE RIDGE
AXIS QUICKLY PASSES EAST BY TOMORROW AFTERNOON LEADING TO A LARGELY
DRY DAY FOR THE INTERIOR.

ANOTHER MORE COHESIVE TROUGH AND FRONTAL SYSTEM WILL DIG OFFSHORE
WITH WARM FRONTAL RAIN TOUCHING THE COAST LATE FRIDAY AFTERNOON WITH
HEAVIER AMOUNTS BY EARLY FRIDAY EVENING. TIMING COULD BE EARLIER
DEPENDING ON MODEL OF CHOICE WITH THE GFS PERHAPS A COUPLE HOURS
FASTER THAN THE ECMWF AND THE NAM SLOWER YET. NAM TYPICALLY DOES NOT
HANDLE WARM PROCESS RAIN VERY WELL SO AM PUTTING LESS WEIGHT ON IT
TO START WITH. AS THE RAIN COMES IN...A COASTAL JET DEVELOPS
BRINGING FAIRLY GUSTY WINDS TO THE COAST AND COAST RANGE BUT NOTHING
TOO OUT OF THE ORDINARY. NOT ANTICIPATING ANY HIGHLIGHTS BUT
PROBABLY A RUN OF THE MILL WINDY COASTAL STORM. THE ASSOCIATED COLD
FRONT COME ASHORE AROUND 12Z FRIDAY MORNING AND CROSSES THE CASCADES
AROUND 17Z WITH COLDER AIR AND LOWERING SNOW LEVELS WITH AND MORE SO
BEHIND IT. PRECIPITATION TAPERS OFF AND BECOMES MORE SHOWERY IN
NATURE BEHIND THE FRONT. EXPECT LIGHT ACCUMULATING SNOW BEGINS AT
WILLAMETTE PASS AROUND DAY BREAK AND LOWERS TO NEAR GOVERNMENT PASS
LATER THAT MORNING. THE SNOW COMES TO BE TOO LITTLE...TOO LATE FOR
MUCH APPRECIABLE INCREASE IN THE SNOW PACK WITH PERHAPS A FEW INCHES
AT THE HIGHER PASSES AND LESS THAN AN INCH FOR GOVERNMENT CAMP.
HIGHER PEAKS COULD SEE UP TO A FOOT...HOWEVER. ANY OF THE MID
ELEVATION SNOW WILL BE RATHER SHORT-LIVED AS SNOW LEVELS IMMEDIATELY
BEGIN RISING IN ANTICIPATION OF THE PACIFIC STORM TRACK BECOMING
CENTERED OVER THE AREA.

MAIN ATTENTION THIS SHIFT HAS BEEN BE PLACED ON THE ATMOSPHERIC
RIVER EVENT SETTING UP TO AFFECT THE REGION THIS WEEKEND WITH
IMPACTS LASTING INTO NEXT WEEK. RAW GFS MODEL RUN ACCUMULATED QPF
AMOUNTS EXCEED 12 INCHES FOR PORTIONS OF THE CASCADES AND 10 INCHES
FOR THE COAST RANGE ENDING MONDAY MORNING. WILL SEE THE WARM RAINS
BEGIN AFFECTING THE COAST RANGE SATURDAY MORNING AND PUSH QUICKLY
INLAND TO THE CASCADES BY SATURDAY AFTERNOON. MOST OF THE HEAVY RAIN
OCCURS BEGINNING SATURDAY NIGHT. THERE WOULD BE DEEP WESTERLY FLOW
FROM THE SURFACE UP TO THE JET LEVEL THUS EXPECT THIS COULD BE AN
IDEAL OROGRAPHIC SITUATION TO EXTRACT A MAXIMUM AMOUNT OF RAIN FROM
WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE SUPPORT FROM THE
ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS FOLLOWING THE
HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT REALITY BRINGS
SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL RUNS STAY
UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM RIVERS
EXCEEDING FLOOD STAGE AS SOON AS SUNDAY EVENING.

HAVE ISSUED SOME OUTLOOK PRODUCTS TODAY LOOKING AHEAD TO FLOODING
POTENTIAL WITH THE CAVEAT THAT MODELS HAVE SHIFTED THE FOCUS FROM
NORTHERN WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA DURING THE
PAST 36 HOURS. ADDITIONAL SHIFTING IS EXPECTED AS WELL AS TIMING
DIFFERENCES. STAY TUNED AS THIS SITUATION EVOLVES OVER TIME.
/JBONK

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS MAINTAIN A
FLATTENED RIDGE OVER THE EASTERN PACIFIC FOR THE WEEKEND THROUGH
EARLY NEXT WEEK. WITH A NEARLY ZONAL JET AND ABUNDANT
MOISTURE...EXPECT PLENTY OF RAINFALL TO CONTINUE THROUGH SUNDAY. ON
MONDAY AND TUESDAY...SOME WEAK RIDGING MOVES OVER THE REGION BUT
SHOWERS LIKELY CONTINUE IN THE MOIST ONSHORE FLOW. AN UPPER TROUGH
DROPS SOUTH OVER THE REGION BY MIDWEEK WITH SOME RATHER COLD AIR AND
ADDITIONAL PRECIPITATION IN STORE. WHILE STILL SOME SIGNIFICANT
UNCERTAINTY EXISTS WITH RESPECT TO THE TIMING OF THE PRECIP VS COLD
AIR AND JUST HOW COLD THE AIR IS...IT DOES APPEAR THAT A SIGNIFICANT
SURGE OF COLD AIR MAY MOVE INTO THE REGION AND THEREFORE...DECREASED
TEMPERATURES ACCORDINGLY FOR THE TUE/WED PERIODS ACROSS THE REGION.
IT DOES APPEAR THAT SNOW LEVELS WILL DROP BELOW PASS LEVELS AT
LEAST...AND PERHAPS DOWN INTO THE FOOTHILL ELEVATIONS LATER
WEDNESDAY INTO THURSDAY. GIVEN THE UNCERTAINTY...THOSE PLANNING
HOLIDAY TRAVEL DURING THIS PERIOD SHOULD MONITOR THE FORECAST.
CULLEN

&&

.AVIATION...VFR CONDITIONS LIKELY TO CONTINUE THROUGH THIS
AFTERNOON. ONSHORE WINDS THIS EVENING BEHIND THE WEAK LOW MOVING
ONSHORE WILL ALLOW FOR CIGS AND VIS TO LOWER TO IFR TONIGHT WITH
THE DEVELOPMENT OF FOG/LOW STRATUS. THIS SHOULD HOLD ON THROUGH
THURSDAY MORNING...STARTING TO LIFT BACK TOWARD VFR AROUND 15 TO 18Z
THURSDAY AS WINDS START TO INCREASE OUT OF THE SOUTH. VFR WILL
CONTINUE THROUGH THURSDAY AFTERNOON...THOUGH LOW-LEVEL WIND SHEAR
WILL BE A CONCERN AT KTTD AND POSSIBLY KPDX AS 20 KT EASTERLY
WINDS FROM THE GORGE UNDERCUT INCREASING SOUTHERLY WINDS ALOFT.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST THIS
EVENING. WEAK WINDS WILL COULD PROMOTE THE DEVELOPMENT OF FOG/LOW
STRATUS AFTER 06Z THURSDAY...DROPPING CIGS AND VIS TO IFR. THIS
SHOULD LIFT BACK TO VFR BY 18Z THURSDAY. -MCCOY

&&

.MARINE...WEAK LOW PRESSURE SYSTEM MOVING NORTHWARD ALONG THE
COAST HAS BROUGHT WINDS UP TO SCA CRITERIA THIS AFTERNOON IN OUR
SOUTHERN WATERS. THIS IS WEAKENING AND MOVING ONSHORE...WHICH
SHOULD ALLOW WINDS TO SUBSIDE FOR A BRIEF PERIOD THIS EVENING.
WINDS WILL BEGIN TO INCREASE ACROSS OUR WATERS THURSDAY MORNING
AHEAD OF A COLD FRONT WHICH WILL MOVE THROUGH OUR WATERS DURING
THE DAY THURSDAY. AHEAD OF THIS FRONT...WINDS LIKELY TO RAMP UP TO
GALE FORCE WITH A COASTAL JET FULLY DEVELOPED BY THURSDAY
EVENING AND PERSIST UNTIL THE FRONT MOVES ONSHORE EARLY FRIDAY
MORNING.

SEAS CURRENTLY AROUND 10-12 FT WILL DROP TO 9 FT LATER THIS
EVENING. SEAS WILL BEGIN TO BUILD AGAIN THURSDAY MORNING AS WINDS
INCREASE AHEAD OF THE COLD FRONT ON THURSDAY. SEAS EXPECTED TO
BUILD TO THE LOW-TO-MIDDLE TEENS THURSDAY EVENING...SUBSIDING TO
10 TO 12 FT EARLY FRIDAY MORNING. A DYNAMIC FETCH APPROACHES EARLY
FRIDAY...BRINGING A LARGE SWELL INTO OUR WATERS. THIS WILL CAUSE
SEAS TO RAPIDLY BUILD FRIDAY MORNING...REACHING 20 FT FRIDAY
EVENING. THE NEXT STRONG FRONT APPROACHES ON SATURDAY...WITH
GALES POSSIBLE...COULD BUILD SEAS ALREADY 15 TO 20 FEET...TO 20
TO 25 FT SATURDAY. -MCCOY

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 4 AM TO 1 PM PST THURSDAY
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.

     GALE WARNING FROM 1 PM THURSDAY TO MIDNIGHT PST THURSDAY NIGHT
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THURSDAY FOR
     COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM PST THURSDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 172252
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
252 PM PST WED DEC 17 2014

.SYNOPSIS...WEAK LOW PRESSURE WILL CROSS THE AREA THIS EVENING WITH
SHOWERS LINGERING OVERNIGHT. EXPECT FAIRLY QUIET WEATHER TO START
THE DAY THURSDAY. A MORE ORGANIZED FRONT WILL BRING GUSTY WINDS TO
THE COAST WITH RAIN SPREADING INLAND THURSDAY NIGHT AND FRIDAY.
RISING SNOW LEVELS WILL LIMIT SNOW TO THE HIGHEST PEAKS. COLDER AIR
BEHIND THE FRONT WILL BRING ACCUMULATING SNOW SHOWERS FOR THE
CASCADES PASSES FRIDAY EVENING AND SATURDAY. MILD AND VERY WET
WEATHER ARRIVED THIS WEEKEND. THERE IS POTENTIAL FOR AN ATMOSPHERIC
RIVER AND ASSOCIATED HEAVY RAIN TO DEVELOP OVER THE AREA AFFECTING
RIVERS INTO NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...A WEAK AND SPLITTING TROUGH
WILL SEND MOST OF ITS ENERGY SOUTH OF OUR AREA TONIGHT. WILL SEE
SHOWERS TAPER OFF OVERNIGHT AS HIGH PRESSURE BEGINS A TRANSIT ACROSS
THE AREA. WILL ALSO SEE CORRESPONDING SNOW LEVELS RISE ABOVE THE
PASSES AND GENERALLY LIMIT THE AMOUNT OF ACCUMULATIONS. THE RIDGE
AXIS QUICKLY PASSES EAST BY TOMORROW AFTERNOON LEADING TO A LARGELY
DRY DAY FOR THE INTERIOR.

ANOTHER MORE COHESIVE TROUGH AND FRONTAL SYSTEM WILL DIG OFFSHORE
WITH WARM FRONTAL RAIN TOUCHING THE COAST LATE FRIDAY AFTERNOON WITH
HEAVIER AMOUNTS BY EARLY FRIDAY EVENING. TIMING COULD BE EARLIER
DEPENDING ON MODEL OF CHOICE WITH THE GFS PERHAPS A COUPLE HOURS
FASTER THAN THE ECMWF AND THE NAM SLOWER YET. NAM TYPICALLY DOES NOT
HANDLE WARM PROCESS RAIN VERY WELL SO AM PUTTING LESS WEIGHT ON IT
TO START WITH. AS THE RAIN COMES IN...A COASTAL JET DEVELOPS
BRINGING FAIRLY GUSTY WINDS TO THE COAST AND COAST RANGE BUT NOTHING
TOO OUT OF THE ORDINARY. NOT ANTICIPATING ANY HIGHLIGHTS BUT
PROBABLY A RUN OF THE MILL WINDY COASTAL STORM. THE ASSOCIATED COLD
FRONT COME ASHORE AROUND 12Z FRIDAY MORNING AND CROSSES THE CASCADES
AROUND 17Z WITH COLDER AIR AND LOWERING SNOW LEVELS WITH AND MORE SO
BEHIND IT. PRECIPITATION TAPERS OFF AND BECOMES MORE SHOWERY IN
NATURE BEHIND THE FRONT. EXPECT LIGHT ACCUMULATING SNOW BEGINS AT
WILLAMETTE PASS AROUND DAY BREAK AND LOWERS TO NEAR GOVERNMENT PASS
LATER THAT MORNING. THE SNOW COMES TO BE TOO LITTLE...TOO LATE FOR
MUCH APPRECIABLE INCREASE IN THE SNOW PACK WITH PERHAPS A FEW INCHES
AT THE HIGHER PASSES AND LESS THAN AN INCH FOR GOVERNMENT CAMP.
HIGHER PEAKS COULD SEE UP TO A FOOT...HOWEVER. ANY OF THE MID
ELEVATION SNOW WILL BE RATHER SHORT-LIVED AS SNOW LEVELS IMMEDIATELY
BEGIN RISING IN ANTICIPATION OF THE PACIFIC STORM TRACK BECOMING
CENTERED OVER THE AREA.

MAIN ATTENTION THIS SHIFT HAS BEEN BE PLACED ON THE ATMOSPHERIC
RIVER EVENT SETTING UP TO AFFECT THE REGION THIS WEEKEND WITH
IMPACTS LASTING INTO NEXT WEEK. RAW GFS MODEL RUN ACCUMULATED QPF
AMOUNTS EXCEED 12 INCHES FOR PORTIONS OF THE CASCADES AND 10 INCHES
FOR THE COAST RANGE ENDING MONDAY MORNING. WILL SEE THE WARM RAINS
BEGIN AFFECTING THE COAST RANGE SATURDAY MORNING AND PUSH QUICKLY
INLAND TO THE CASCADES BY SATURDAY AFTERNOON. MOST OF THE HEAVY RAIN
OCCURS BEGINNING SATURDAY NIGHT. THERE WOULD BE DEEP WESTERLY FLOW
FROM THE SURFACE UP TO THE JET LEVEL THUS EXPECT THIS COULD BE AN
IDEAL OROGRAPHIC SITUATION TO EXTRACT A MAXIMUM AMOUNT OF RAIN FROM
WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE SUPPORT FROM THE
ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS FOLLOWING THE
HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT REALITY BRINGS
SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL RUNS STAY
UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM RIVERS
EXCEEDING FLOOD STAGE AS SOON AS SUNDAY EVENING.

HAVE ISSUED SOME OUTLOOK PRODUCTS TODAY LOOKING AHEAD TO FLOODING
POTENTIAL WITH THE CAVEAT THAT MODELS HAVE SHIFTED THE FOCUS FROM
NORTHERN WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA DURING THE
PAST 36 HOURS. ADDITIONAL SHIFTING IS EXPECTED AS WELL AS TIMING
DIFFERENCES. STAY TUNED AS THIS SITUATION EVOLVES OVER TIME.
/JBONK

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS MAINTAIN A
FLATTENED RIDGE OVER THE EASTERN PACIFIC FOR THE WEEKEND THROUGH
EARLY NEXT WEEK. WITH A NEARLY ZONAL JET AND ABUNDANT
MOISTURE...EXPECT PLENTY OF RAINFALL TO CONTINUE THROUGH SUNDAY. ON
MONDAY AND TUESDAY...SOME WEAK RIDGING MOVES OVER THE REGION BUT
SHOWERS LIKELY CONTINUE IN THE MOIST ONSHORE FLOW. AN UPPER TROUGH
DROPS SOUTH OVER THE REGION BY MIDWEEK WITH SOME RATHER COLD AIR AND
ADDITIONAL PRECIPITATION IN STORE. WHILE STILL SOME SIGNIFICANT
UNCERTAINTY EXISTS WITH RESPECT TO THE TIMING OF THE PRECIP VS COLD
AIR AND JUST HOW COLD THE AIR IS...IT DOES APPEAR THAT A SIGNIFICANT
SURGE OF COLD AIR MAY MOVE INTO THE REGION AND THEREFORE...DECREASED
TEMPERATURES ACCORDINGLY FOR THE TUE/WED PERIODS ACROSS THE REGION.
IT DOES APPEAR THAT SNOW LEVELS WILL DROP BELOW PASS LEVELS AT
LEAST...AND PERHAPS DOWN INTO THE FOOTHILL ELEVATIONS LATER
WEDNESDAY INTO THURSDAY. GIVEN THE UNCERTAINTY...THOSE PLANNING
HOLIDAY TRAVEL DURING THIS PERIOD SHOULD MONITOR THE FORECAST.
CULLEN

&&

.AVIATION...VFR CONDITIONS LIKELY TO CONTINUE THROUGH THIS
AFTERNOON. ONSHORE WINDS THIS EVENING BEHIND THE WEAK LOW MOVING
ONSHORE WILL ALLOW FOR CIGS AND VIS TO LOWER TO IFR TONIGHT WITH
THE DEVELOPMENT OF FOG/LOW STRATUS. THIS SHOULD HOLD ON THROUGH
THURSDAY MORNING...STARTING TO LIFT BACK TOWARD VFR AROUND 15 TO 18Z
THURSDAY AS WINDS START TO INCREASE OUT OF THE SOUTH. VFR WILL
CONTINUE THROUGH THURSDAY AFTERNOON...THOUGH LOW-LEVEL WIND SHEAR
WILL BE A CONCERN AT KTTD AND POSSIBLY KPDX AS 20 KT EASTERLY
WINDS FROM THE GORGE UNDERCUT INCREASING SOUTHERLY WINDS ALOFT.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST THIS
EVENING. WEAK WINDS WILL COULD PROMOTE THE DEVELOPMENT OF FOG/LOW
STRATUS AFTER 06Z THURSDAY...DROPPING CIGS AND VIS TO IFR. THIS
SHOULD LIFT BACK TO VFR BY 18Z THURSDAY. -MCCOY

&&

.MARINE...WEAK LOW PRESSURE SYSTEM MOVING NORTHWARD ALONG THE
COAST HAS BROUGHT WINDS UP TO SCA CRITERIA THIS AFTERNOON IN OUR
SOUTHERN WATERS. THIS IS WEAKENING AND MOVING ONSHORE...WHICH
SHOULD ALLOW WINDS TO SUBSIDE FOR A BRIEF PERIOD THIS EVENING.
WINDS WILL BEGIN TO INCREASE ACROSS OUR WATERS THURSDAY MORNING
AHEAD OF A COLD FRONT WHICH WILL MOVE THROUGH OUR WATERS DURING
THE DAY THURSDAY. AHEAD OF THIS FRONT...WINDS LIKELY TO RAMP UP TO
GALE FORCE WITH A COASTAL JET FULLY DEVELOPED BY THURSDAY
EVENING AND PERSIST UNTIL THE FRONT MOVES ONSHORE EARLY FRIDAY
MORNING.

SEAS CURRENTLY AROUND 10-12 FT WILL DROP TO 9 FT LATER THIS
EVENING. SEAS WILL BEGIN TO BUILD AGAIN THURSDAY MORNING AS WINDS
INCREASE AHEAD OF THE COLD FRONT ON THURSDAY. SEAS EXPECTED TO
BUILD TO THE LOW-TO-MIDDLE TEENS THURSDAY EVENING...SUBSIDING TO
10 TO 12 FT EARLY FRIDAY MORNING. A DYNAMIC FETCH APPROACHES EARLY
FRIDAY...BRINGING A LARGE SWELL INTO OUR WATERS. THIS WILL CAUSE
SEAS TO RAPIDLY BUILD FRIDAY MORNING...REACHING 20 FT FRIDAY
EVENING. THE NEXT STRONG FRONT APPROACHES ON SATURDAY...WITH
GALES POSSIBLE...COULD BUILD SEAS ALREADY 15 TO 20 FEET...TO 20
TO 25 FT SATURDAY. -MCCOY

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 4 AM TO 1 PM PST THURSDAY
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.

     GALE WARNING FROM 1 PM THURSDAY TO MIDNIGHT PST THURSDAY NIGHT
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THURSDAY FOR
     COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM PST THURSDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 172252
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
252 PM PST WED DEC 17 2014

.SYNOPSIS...WEAK LOW PRESSURE WILL CROSS THE AREA THIS EVENING WITH
SHOWERS LINGERING OVERNIGHT. EXPECT FAIRLY QUIET WEATHER TO START
THE DAY THURSDAY. A MORE ORGANIZED FRONT WILL BRING GUSTY WINDS TO
THE COAST WITH RAIN SPREADING INLAND THURSDAY NIGHT AND FRIDAY.
RISING SNOW LEVELS WILL LIMIT SNOW TO THE HIGHEST PEAKS. COLDER AIR
BEHIND THE FRONT WILL BRING ACCUMULATING SNOW SHOWERS FOR THE
CASCADES PASSES FRIDAY EVENING AND SATURDAY. MILD AND VERY WET
WEATHER ARRIVED THIS WEEKEND. THERE IS POTENTIAL FOR AN ATMOSPHERIC
RIVER AND ASSOCIATED HEAVY RAIN TO DEVELOP OVER THE AREA AFFECTING
RIVERS INTO NEXT WEEK.

&&

.SHORT TERM...TONIGHT THROUGH SATURDAY...A WEAK AND SPLITTING TROUGH
WILL SEND MOST OF ITS ENERGY SOUTH OF OUR AREA TONIGHT. WILL SEE
SHOWERS TAPER OFF OVERNIGHT AS HIGH PRESSURE BEGINS A TRANSIT ACROSS
THE AREA. WILL ALSO SEE CORRESPONDING SNOW LEVELS RISE ABOVE THE
PASSES AND GENERALLY LIMIT THE AMOUNT OF ACCUMULATIONS. THE RIDGE
AXIS QUICKLY PASSES EAST BY TOMORROW AFTERNOON LEADING TO A LARGELY
DRY DAY FOR THE INTERIOR.

ANOTHER MORE COHESIVE TROUGH AND FRONTAL SYSTEM WILL DIG OFFSHORE
WITH WARM FRONTAL RAIN TOUCHING THE COAST LATE FRIDAY AFTERNOON WITH
HEAVIER AMOUNTS BY EARLY FRIDAY EVENING. TIMING COULD BE EARLIER
DEPENDING ON MODEL OF CHOICE WITH THE GFS PERHAPS A COUPLE HOURS
FASTER THAN THE ECMWF AND THE NAM SLOWER YET. NAM TYPICALLY DOES NOT
HANDLE WARM PROCESS RAIN VERY WELL SO AM PUTTING LESS WEIGHT ON IT
TO START WITH. AS THE RAIN COMES IN...A COASTAL JET DEVELOPS
BRINGING FAIRLY GUSTY WINDS TO THE COAST AND COAST RANGE BUT NOTHING
TOO OUT OF THE ORDINARY. NOT ANTICIPATING ANY HIGHLIGHTS BUT
PROBABLY A RUN OF THE MILL WINDY COASTAL STORM. THE ASSOCIATED COLD
FRONT COME ASHORE AROUND 12Z FRIDAY MORNING AND CROSSES THE CASCADES
AROUND 17Z WITH COLDER AIR AND LOWERING SNOW LEVELS WITH AND MORE SO
BEHIND IT. PRECIPITATION TAPERS OFF AND BECOMES MORE SHOWERY IN
NATURE BEHIND THE FRONT. EXPECT LIGHT ACCUMULATING SNOW BEGINS AT
WILLAMETTE PASS AROUND DAY BREAK AND LOWERS TO NEAR GOVERNMENT PASS
LATER THAT MORNING. THE SNOW COMES TO BE TOO LITTLE...TOO LATE FOR
MUCH APPRECIABLE INCREASE IN THE SNOW PACK WITH PERHAPS A FEW INCHES
AT THE HIGHER PASSES AND LESS THAN AN INCH FOR GOVERNMENT CAMP.
HIGHER PEAKS COULD SEE UP TO A FOOT...HOWEVER. ANY OF THE MID
ELEVATION SNOW WILL BE RATHER SHORT-LIVED AS SNOW LEVELS IMMEDIATELY
BEGIN RISING IN ANTICIPATION OF THE PACIFIC STORM TRACK BECOMING
CENTERED OVER THE AREA.

MAIN ATTENTION THIS SHIFT HAS BEEN BE PLACED ON THE ATMOSPHERIC
RIVER EVENT SETTING UP TO AFFECT THE REGION THIS WEEKEND WITH
IMPACTS LASTING INTO NEXT WEEK. RAW GFS MODEL RUN ACCUMULATED QPF
AMOUNTS EXCEED 12 INCHES FOR PORTIONS OF THE CASCADES AND 10 INCHES
FOR THE COAST RANGE ENDING MONDAY MORNING. WILL SEE THE WARM RAINS
BEGIN AFFECTING THE COAST RANGE SATURDAY MORNING AND PUSH QUICKLY
INLAND TO THE CASCADES BY SATURDAY AFTERNOON. MOST OF THE HEAVY RAIN
OCCURS BEGINNING SATURDAY NIGHT. THERE WOULD BE DEEP WESTERLY FLOW
FROM THE SURFACE UP TO THE JET LEVEL THUS EXPECT THIS COULD BE AN
IDEAL OROGRAPHIC SITUATION TO EXTRACT A MAXIMUM AMOUNT OF RAIN FROM
WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE SUPPORT FROM THE
ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS FOLLOWING THE
HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT REALITY BRINGS
SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL RUNS STAY
UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM RIVERS
EXCEEDING FLOOD STAGE AS SOON AS SUNDAY EVENING.

HAVE ISSUED SOME OUTLOOK PRODUCTS TODAY LOOKING AHEAD TO FLOODING
POTENTIAL WITH THE CAVEAT THAT MODELS HAVE SHIFTED THE FOCUS FROM
NORTHERN WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA DURING THE
PAST 36 HOURS. ADDITIONAL SHIFTING IS EXPECTED AS WELL AS TIMING
DIFFERENCES. STAY TUNED AS THIS SITUATION EVOLVES OVER TIME.
/JBONK

.LONG TERM...SATURDAY NIGHT THROUGH WEDNESDAY...MODELS MAINTAIN A
FLATTENED RIDGE OVER THE EASTERN PACIFIC FOR THE WEEKEND THROUGH
EARLY NEXT WEEK. WITH A NEARLY ZONAL JET AND ABUNDANT
MOISTURE...EXPECT PLENTY OF RAINFALL TO CONTINUE THROUGH SUNDAY. ON
MONDAY AND TUESDAY...SOME WEAK RIDGING MOVES OVER THE REGION BUT
SHOWERS LIKELY CONTINUE IN THE MOIST ONSHORE FLOW. AN UPPER TROUGH
DROPS SOUTH OVER THE REGION BY MIDWEEK WITH SOME RATHER COLD AIR AND
ADDITIONAL PRECIPITATION IN STORE. WHILE STILL SOME SIGNIFICANT
UNCERTAINTY EXISTS WITH RESPECT TO THE TIMING OF THE PRECIP VS COLD
AIR AND JUST HOW COLD THE AIR IS...IT DOES APPEAR THAT A SIGNIFICANT
SURGE OF COLD AIR MAY MOVE INTO THE REGION AND THEREFORE...DECREASED
TEMPERATURES ACCORDINGLY FOR THE TUE/WED PERIODS ACROSS THE REGION.
IT DOES APPEAR THAT SNOW LEVELS WILL DROP BELOW PASS LEVELS AT
LEAST...AND PERHAPS DOWN INTO THE FOOTHILL ELEVATIONS LATER
WEDNESDAY INTO THURSDAY. GIVEN THE UNCERTAINTY...THOSE PLANNING
HOLIDAY TRAVEL DURING THIS PERIOD SHOULD MONITOR THE FORECAST.
CULLEN

&&

.AVIATION...VFR CONDITIONS LIKELY TO CONTINUE THROUGH THIS
AFTERNOON. ONSHORE WINDS THIS EVENING BEHIND THE WEAK LOW MOVING
ONSHORE WILL ALLOW FOR CIGS AND VIS TO LOWER TO IFR TONIGHT WITH
THE DEVELOPMENT OF FOG/LOW STRATUS. THIS SHOULD HOLD ON THROUGH
THURSDAY MORNING...STARTING TO LIFT BACK TOWARD VFR AROUND 15 TO 18Z
THURSDAY AS WINDS START TO INCREASE OUT OF THE SOUTH. VFR WILL
CONTINUE THROUGH THURSDAY AFTERNOON...THOUGH LOW-LEVEL WIND SHEAR
WILL BE A CONCERN AT KTTD AND POSSIBLY KPDX AS 20 KT EASTERLY
WINDS FROM THE GORGE UNDERCUT INCREASING SOUTHERLY WINDS ALOFT.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST THIS
EVENING. WEAK WINDS WILL COULD PROMOTE THE DEVELOPMENT OF FOG/LOW
STRATUS AFTER 06Z THURSDAY...DROPPING CIGS AND VIS TO IFR. THIS
SHOULD LIFT BACK TO VFR BY 18Z THURSDAY. -MCCOY

&&

.MARINE...WEAK LOW PRESSURE SYSTEM MOVING NORTHWARD ALONG THE
COAST HAS BROUGHT WINDS UP TO SCA CRITERIA THIS AFTERNOON IN OUR
SOUTHERN WATERS. THIS IS WEAKENING AND MOVING ONSHORE...WHICH
SHOULD ALLOW WINDS TO SUBSIDE FOR A BRIEF PERIOD THIS EVENING.
WINDS WILL BEGIN TO INCREASE ACROSS OUR WATERS THURSDAY MORNING
AHEAD OF A COLD FRONT WHICH WILL MOVE THROUGH OUR WATERS DURING
THE DAY THURSDAY. AHEAD OF THIS FRONT...WINDS LIKELY TO RAMP UP TO
GALE FORCE WITH A COASTAL JET FULLY DEVELOPED BY THURSDAY
EVENING AND PERSIST UNTIL THE FRONT MOVES ONSHORE EARLY FRIDAY
MORNING.

SEAS CURRENTLY AROUND 10-12 FT WILL DROP TO 9 FT LATER THIS
EVENING. SEAS WILL BEGIN TO BUILD AGAIN THURSDAY MORNING AS WINDS
INCREASE AHEAD OF THE COLD FRONT ON THURSDAY. SEAS EXPECTED TO
BUILD TO THE LOW-TO-MIDDLE TEENS THURSDAY EVENING...SUBSIDING TO
10 TO 12 FT EARLY FRIDAY MORNING. A DYNAMIC FETCH APPROACHES EARLY
FRIDAY...BRINGING A LARGE SWELL INTO OUR WATERS. THIS WILL CAUSE
SEAS TO RAPIDLY BUILD FRIDAY MORNING...REACHING 20 FT FRIDAY
EVENING. THE NEXT STRONG FRONT APPROACHES ON SATURDAY...WITH
GALES POSSIBLE...COULD BUILD SEAS ALREADY 15 TO 20 FEET...TO 20
TO 25 FT SATURDAY. -MCCOY

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 4 AM TO 1 PM PST THURSDAY
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM.

     GALE WARNING FROM 1 PM THURSDAY TO MIDNIGHT PST THURSDAY NIGHT
     FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THURSDAY FOR
     COASTAL WATERS FROM CASCADE HEAD OR TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM PST THURSDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPDT 172242
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
242 PM PST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

.LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

&&

.AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     ORZ507-508.

WA...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/78/78








000
FXUS66 KPDT 172242
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
242 PM PST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

.LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

&&

.AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     ORZ507-508.

WA...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/78/78








000
FXUS66 KPDT 172242
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
242 PM PST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

.LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

&&

.AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     ORZ507-508.

WA...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/78/78








000
FXUS66 KPDT 172242
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
242 PM PST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY NIGHT...ONE LAST WEAK
DISTURBANCE WILL MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
CAUSE ISOLATED TO SCATTERED RAIN OR SNOW SHOWERS. THE STAGNANT AIR
MASS ACROSS THE BASIN WILL CONTINUE INTO THURSDAY, AND AS SUCH
PATCHY TO AREAS OF FOG WILL DEVELOP OR EXPAND IN COVERAGE. THE
DENSEST FOG WILL GENERALLY OCCUR BETWEEN THE ELEVATIONS OF 1500 AND
3000 FEET MSL. AT THIS TIME HAVE ENOUGH CONFIDENCE TO ISSUE DENSE
FOG ADVISORIES FOR THE BLUE MOUNTAIN FOOTHILLS AND THE KITTITAS
VALLEY. PORTIONS OF NORTH-CENTRAL AND CENTRAL OREGON MAY NEED TO BE
ADDED DEPENDING ON DEVELOPMENT IN THESE AREAS. GENERALLY EXPECT
TEMPS TO REMAIN ABOVE FREEZING IN THE FOGGY AREAS, THOUGH SOME
LOCATIONS WILL SEE LOWS BETWEEN 30 AND 32 DEGREES. THUS SOME LOCAL
FREEZING FOG WILL BE POSSIBLE. OTHER THAN A FEW LINGERING SHOWERS,
CONDITIONS WILL BE GENERALLY DRY THURSDAY DUE TO A TRANSITORY UPPER
LEVEL HIGH PRESSURE RIDGE. MOST FOGGY AREAS SHOULD SEE IMPROVEMENT
BY LATE MORNING THURSDAY. A STRONGER AND WETTER PACIFIC SYSTEM WILL
BEGIN TO MOVE INTO THE REGION THURSDAY NIGHT. PRECIP WILL GRADUALLY
SPREAD FROM WEST TO EAST THROUGH THE NIGHT. SNOW LEVELS WILL RANGE
FROM NEAR 2000 FEET IN WESTERN KITTITAS COUNTY TO BETWEEN 3500 AND
4500 FEET ELSEWHERE. SNOW AMOUNTS AT THIS TIME ARE EXPECTED TO BE 3
INCHES OR LESS OVER THE HIGHER ELEVATIONS. THIS SYSTEM WILL ALSO
BEGIN TO INCREASE SOUTHERLY WINDS OVER A GOOD PORTION OF OUR OREGON
ZONES. SHOULD SEE AT LEAST WINDY CONDITIONS OVER THE SOUTHERN GRANDE
RONDE VALLEY. THE INCREASING CLOUD COVER, PRECIP AND WINDS SHOULD
LIMIT FOG DEVELOPMENT IN THE BASIN. 90

.LONG TERM...FRIDAY THROUGH WEDNESDAY...ACTIVE WEATHER PATTERN IS
STORE THROUGH THE PERIOD WITH SEVERAL STORM SYSTEMS TO IMPACT THE
REGION. THE FLOW PATTERN WILL BE FAST ZONAL FOR MUCH OF THE TIME BUT
INDICATIONS ARE THAT IT WILL TRANSITION TO MORE NWLY TUESDAY INTO
WEDNESDAY AS ARCTIC AIR BEGINS TO FILTER INTO THE REGION. FOR FRIDAY
INTO SUNDAY EXPECT PERIODS OF MOSTLY RAIN HEAVY AT TIMES...
ESPECIALLY MOUNTAINS. THERE COULD BE IN EXCESS OF 2 INCHES OF QPF IN
THE MOUNTAINS WITH RISES LIKELY ON RIVERS AND STREAMS. IT IS
POSSIBLE THAT THERE COULD BE SOME SNOW ALONG THE I-90 CORRIDOR IN NW
KITTITAS COUNTY IF SNOW LEVELS ARE JUST A BIT LOWER THAN CURRENTLY
FORECAST. THERE IS ALSO THE POTENTIAL FOR A HIGH WIND EVENT SATURDAY
NIGHT INTO SUNDAY LOWER ELEVATIONS WITH A STRONG WESTERLY LOW LEVEL
JET AND TIGHT SURFACE PRESSURE GRADIENT. FOR NOW HAVE BEEFED UP THE
WINDS TO ADVISORY LEVELS FOR THAT TIME PERIOD. THERE WILL CONTINUE
TO BE A CHANCE OF RAIN ON MONDAY AND TUESDAY BUT THE RAIN WILL
TRANSITION TO SNOW BY WEDNESDAY (CHRISTMAS EVE) AS SNOW LEVELS LOWER
WITH THE ARRIVAL OF THE ARCTIC AIR. 78

&&

.AVIATION...00Z TAFS...IFR/LIFR CONDITIONS WILL PREVAIL THROUGH THE
FORECAST PERIOD. SOME IMPROVEMENT IN CONDITIONS HAS OCCURRED THIS
AFTERNOON AT THE TAF SITES BUT EXPECT CIGS/VSBYS TO LOWER THIS
EVENING AND ESPECIALLY OVERNIGHT TO IFR/LIFR. THESE CONDITIONS WILL
CONTINUE INTO THE MORNING HOURS ON THURSDAY WITH SOME IMPROVEMENT
POSSIBLE AFTER 18Z THURSDAY. WINDS WILL BE LIGHT. THERE COULD BE A
LITTLE RAIN AROUND BUT SHOULD NOT AMOUNT TO MORE THAN A FEW
HUNDREDTHS OF AN INCH. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  30  38  33  42 /  30  10  50  70
ALW  32  39  35  42 /  30  10  50  80
PSC  34  41  34  43 /  20  10  60  70
YKM  33  39  33  40 /  30  10  70  40
HRI  34  41  33  43 /  30  10  60  70
ELN  33  38  33  36 /  30  10  70  50
RDM  29  43  32  43 /  30  10  60  60
LGD  32  45  35  40 /  40  20  40  80
GCD  31  42  32  39 /  30  20  40  80
DLS  38  44  37  44 /  40  10  70  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     ORZ507-508.

WA...DENSE FOG ADVISORY FROM 6 PM THIS EVENING TO 10 AM PST THURSDAY
     WAZ026-029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/78/78







  [top]

000
FXUS66 KMFR 172206
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
206 PM PST WED DEC 17 2014

.DISCUSSION...ANOTHER WEAK UPPER TROUGH IS NEAR THE COAST AND THIS
WILL MOVE INLAND THIS EVENING. CURRENT RADAR SHOWS TWO AREAS OF
SCATTERED SHOWERS. THE FIRST IS IN NORTHEAST SISKIYOU AND KLAMATH
COUNTY AND THE SECOND IS MOVING TOWARDS THE COAST. THIS SECOND
FEATURE WILL MOVE INLAND THIS EVENING AND BRING SCATTERED SHOWERS
OVER NORTHERN CAL AND SOUTHWEST OREGON. THE LATEST RAP MODELS
DEPICTS THE PLACEMENT OF THE PRECIPITATION WELL AND WILL FOLLOW THIS
FOR THIS EVENING. THE UPPER TROUGH WILL WEAKEN AS IT MOVES EAST AND
SHORTWAVE RIDGING BEGINS TO BUILD IN OVERNIGHT. THIS SHOULD SHUT OFF
THE SHOWER ACTIVITY OVER MOST OF THE AREA, ALTHOUGH SOME RESIDUAL
SHOWERS COULD LINGER IN SOUTHEAST SISKIYOU AND MODOC COUNTIES.

WE`LL CATCH A DRY BREAK ON THURSDAY WITH THE RIDGE AXIS OVER THE
AREA, BUT THIS WILL BE SHORT LIVED. THE MODELS SHOW A STRONGER FRONT
APPROACHING THE AREA THURSDAY AFTERNOON BRINGING INCREASING SOUTH
WINDS OVER THE MARINE WATERS WHICH ARE EXPECTED TO GET CLOSE TO
GALES. PRECIPITATION COULD ALSO REACH THE COAST AS EARLY AS THURSDAY
AFTERNOON. THE FRONT WILL MOVE INLAND THURSDAY NIGHT BRINGING
MODERATE TO HEAVY PRECIPITATION OVER THE USUAL SUSPECTS...THE COAST
RANGE...COASTAL MOUNTAINS AND CASCADES. HOWEVER THE MODELS ARE IN
GOOD AGREEMENT THE FRONT WILL BE A QUICK MOVER AND SO WE WON`T GET
SIGNIFICANT PRECIPITATION AMOUNTS. SNOW LEVELS WILL START OUT HIGH
THURSDAY NIGHT, BUT WILL DROP TO AROUND 4500 FEET EARLY FRIDAY
MORNING. SO IT`S A GOOD BET THE MOUNTAIN PASSES WILL GET
ACCUMULATING SNOW STARTING LATE THURSDAY NIGHT THROUGH FRIDAY
MORNING. CURRENT THINKING IS CRATER LAKE COULD PICK UP AT LEAST 6
INCHES OR MORE AND A FEW INCHES ARE POSSIBLE OVER SISKIYOU SUMMIT
AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS WILL CHANGE, SO
STAY TUNED FOR THE LATEST UPDATES.

THE ABOVE MENTIONED FRONT WILL QUICKLY MOVE THROUGH FRIDAY AND WE`LL
CATCH A RELATIVE BREAK IN PRECIPITATION FRIDAY AFTERNOON AND EVENING.
BUT AGAIN THIS WILL BE SHORT LIVED. THE MODELS ARE IN PRETTY GOOD
AGREEMENT SHOWING A STRONG WARM FRONT ARRIVING AT THE COAST LATE
FRIDAY NIGHT AND MOVING OVER THE AREA SATURDAY. THIS FRONT HAS A LOT
OF JUICE WITH IT AND HEAVY PRECIPITATION WILL LIKELY IMPACT THE
COAST...COAST RANGE...COASTAL MOUNTAINS AND CASCADES. MODERATE TO
HEAVY PRECIPITATION WILL ALSO IMPACT MUCH OF THE WESTSIDE VALLEYS. OF
NOTE THE IVT TRANSPORT (WHICH IS GFS BASED) PUTS THE HIGHEST VALUES
IN CENTRAL AND NORTHWEST OREGON. EVEN THE GEFS ENSEMBLE MEAN IS
SIMILAR TO THE OPERATIONAL GFS. ADDITIONALY, THE UPPER FLOW IS
ALMOST DUE WEST WHICH WILL SQUEEZE OUT EVEN MORE MOISTURE ALONG THE
COAST RANGE. ALSO WINDS WILL INCREASE AHEAD OF THE FRONT AND THERE
IS A CHANCE FOR GALE FORCE WINDS OVER THE MARINE WATERS AND MODERATE
TO STRONG WINDS OVER THE COAST AND HEADLANDS. IF THAT WEREN`T ENOUGH
THERE IS CONCERN FOR SNOW EAST OF THE CASCADES AS THE WARM FRONT
ARRIVES. MODEL SOUNDINGS SUPPORT THE IDEA THAT ENOUGH COLD AIR WILL
BE PRESENT NEAR THE SURFACE AND THIS IN COMBINATION WITH OVERRUNNING
PRECIPITATION COULD BRING A PERIOD OF SNOW SATURDAY MORNING.

STRONG WESTERLY FLOW CONTINUES SATURDAY NIGHT WITH THE HEAVIEST
PRECIPITATION WEST OF THE CASCADES, BUT SNOW LEVELS WILL JUMP UP TO
AROUND 7000 FEET SATURDAY AFTERNOON AND REMAIN HIGH SATURDAY NIGHT.
-PETRUCELLI

LONG-TERM FORECAST...SUNDAY THROUGH WEDNESDAY.  A BROAD LONG WAVE
RIDGE WILL BE IN PLACE AT THE BEGINNING OF THE EXTENDED PERIOD WITH
WITH GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP
OF THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL
REMAIN IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE
ZONAL TUESDAY.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL. THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND WILL BE OVER THE CWA SUNDAY. REINFORCING SHORT WAVES
WILL KEEP THE PRECIPITATION GOING THROUGH MOST OF MONDAY. THE BULK
OF THE ASSOCIATED PRECIPITATION WILL FALL ALONG THE COAST...COAST
RANGE...AND UMPQUA BASIN. AMOUNTS WILL BE SIGNIFICANT BUT NOT
EXCESSIVE...NO FLOODING PROBLEMS ARE ANTICIPATED. SNOW LEVELS WILL
BE ABOVE 7000 FEET.

MONDAY NIGHT INTO TUESDAY LOOK TO BE MOSTLY DRY WITH NEARLY ALL THE
ACTION TO THE NORTH OF THE AREA.

THE RIDGE WILL BREAK DOWN WEDNESDAY AND A LONG WAVE TROUGH WILL
BEGIN TO DIG OFFSHORE.  THIS CHANGE IN PATTERN WILL SUPPORT A FRONT
MOVING ONSHORE WEDNESDAY. THIS WILL BE THE WETTEST SYSTEM OF THE
EXTENDED PERIOD IF THE CURRENT EC/GFS MODEL SOLUTIONS PAN OUT. SNOW
LEVELS MAY ALSO FALL AS LOW AS 4000 FEET BEHIND THE FRONT WEDNESDAY
NIGHT...SO SNOW MAY RETURN TO THE PASSES AROUND THAT TIME. -JRS


&&

.AVIATION...BASED ON THE 17/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY WITH AREAS OF HIGHER TERRAIN OBSCURED...EXCEPT FOR
WESTERN AND SOUTH CENTRAL SISKIYOU COUNTY...WHERE AREAS OF MVFR CIGS
WILL PREVAIL THROUGH THURSDAY MORNING.  WIDESPREAD MVFR CIGS AND
AREAS OF IFR CIGS/VSBYS WILL RETURN TO THE WEST SIDE TONIGHT. KOTH
WILL BE AFFECTED BY THE MVFR CIGS AND KRBG AND KMFR WILL BE
AFFECTED BY THE IFR CIGS/VSBYS. ALL AREAS WILL CLEAR TO VFR BY
THURSDAY AFTERNOON. -JRS


&&

.MARINE...UPDATED 935 AM PST WED DEC 17 2014...WEAK LOW PRESSURE
SYSTEMS WILL MOVE THROUGH THE AREA TODAY AND TONIGHT. SOUTHWEST
SWELL DOMINATED SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY.
THURSDAY INTO THURSDAY NIGHT A STRONGER FRONTAL SYSTEM WILL LIKELY
BRING GALE FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. HEAVY WEST
SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY MORNING. IT
WILL PEAK FRIDAY NIGHT AT AROUND 19 FEET AT 18 SECONDS. A WARM FRONT
WILL MOVE THROUGH FRIDAY NIGHT...FOLLOWED BY A COLD FRONT SATURDAY.
OFFSHORE HIGH PRESSURE WILL BUILD SATURDAY NIGHT INTO SUNDAY. -JRS


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.

$$



000
FXUS66 KMFR 172206
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
206 PM PST WED DEC 17 2014

.DISCUSSION...ANOTHER WEAK UPPER TROUGH IS NEAR THE COAST AND THIS
WILL MOVE INLAND THIS EVENING. CURRENT RADAR SHOWS TWO AREAS OF
SCATTERED SHOWERS. THE FIRST IS IN NORTHEAST SISKIYOU AND KLAMATH
COUNTY AND THE SECOND IS MOVING TOWARDS THE COAST. THIS SECOND
FEATURE WILL MOVE INLAND THIS EVENING AND BRING SCATTERED SHOWERS
OVER NORTHERN CAL AND SOUTHWEST OREGON. THE LATEST RAP MODELS
DEPICTS THE PLACEMENT OF THE PRECIPITATION WELL AND WILL FOLLOW THIS
FOR THIS EVENING. THE UPPER TROUGH WILL WEAKEN AS IT MOVES EAST AND
SHORTWAVE RIDGING BEGINS TO BUILD IN OVERNIGHT. THIS SHOULD SHUT OFF
THE SHOWER ACTIVITY OVER MOST OF THE AREA, ALTHOUGH SOME RESIDUAL
SHOWERS COULD LINGER IN SOUTHEAST SISKIYOU AND MODOC COUNTIES.

WE`LL CATCH A DRY BREAK ON THURSDAY WITH THE RIDGE AXIS OVER THE
AREA, BUT THIS WILL BE SHORT LIVED. THE MODELS SHOW A STRONGER FRONT
APPROACHING THE AREA THURSDAY AFTERNOON BRINGING INCREASING SOUTH
WINDS OVER THE MARINE WATERS WHICH ARE EXPECTED TO GET CLOSE TO
GALES. PRECIPITATION COULD ALSO REACH THE COAST AS EARLY AS THURSDAY
AFTERNOON. THE FRONT WILL MOVE INLAND THURSDAY NIGHT BRINGING
MODERATE TO HEAVY PRECIPITATION OVER THE USUAL SUSPECTS...THE COAST
RANGE...COASTAL MOUNTAINS AND CASCADES. HOWEVER THE MODELS ARE IN
GOOD AGREEMENT THE FRONT WILL BE A QUICK MOVER AND SO WE WON`T GET
SIGNIFICANT PRECIPITATION AMOUNTS. SNOW LEVELS WILL START OUT HIGH
THURSDAY NIGHT, BUT WILL DROP TO AROUND 4500 FEET EARLY FRIDAY
MORNING. SO IT`S A GOOD BET THE MOUNTAIN PASSES WILL GET
ACCUMULATING SNOW STARTING LATE THURSDAY NIGHT THROUGH FRIDAY
MORNING. CURRENT THINKING IS CRATER LAKE COULD PICK UP AT LEAST 6
INCHES OR MORE AND A FEW INCHES ARE POSSIBLE OVER SISKIYOU SUMMIT
AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS WILL CHANGE, SO
STAY TUNED FOR THE LATEST UPDATES.

THE ABOVE MENTIONED FRONT WILL QUICKLY MOVE THROUGH FRIDAY AND WE`LL
CATCH A RELATIVE BREAK IN PRECIPITATION FRIDAY AFTERNOON AND EVENING.
BUT AGAIN THIS WILL BE SHORT LIVED. THE MODELS ARE IN PRETTY GOOD
AGREEMENT SHOWING A STRONG WARM FRONT ARRIVING AT THE COAST LATE
FRIDAY NIGHT AND MOVING OVER THE AREA SATURDAY. THIS FRONT HAS A LOT
OF JUICE WITH IT AND HEAVY PRECIPITATION WILL LIKELY IMPACT THE
COAST...COAST RANGE...COASTAL MOUNTAINS AND CASCADES. MODERATE TO
HEAVY PRECIPITATION WILL ALSO IMPACT MUCH OF THE WESTSIDE VALLEYS. OF
NOTE THE IVT TRANSPORT (WHICH IS GFS BASED) PUTS THE HIGHEST VALUES
IN CENTRAL AND NORTHWEST OREGON. EVEN THE GEFS ENSEMBLE MEAN IS
SIMILAR TO THE OPERATIONAL GFS. ADDITIONALY, THE UPPER FLOW IS
ALMOST DUE WEST WHICH WILL SQUEEZE OUT EVEN MORE MOISTURE ALONG THE
COAST RANGE. ALSO WINDS WILL INCREASE AHEAD OF THE FRONT AND THERE
IS A CHANCE FOR GALE FORCE WINDS OVER THE MARINE WATERS AND MODERATE
TO STRONG WINDS OVER THE COAST AND HEADLANDS. IF THAT WEREN`T ENOUGH
THERE IS CONCERN FOR SNOW EAST OF THE CASCADES AS THE WARM FRONT
ARRIVES. MODEL SOUNDINGS SUPPORT THE IDEA THAT ENOUGH COLD AIR WILL
BE PRESENT NEAR THE SURFACE AND THIS IN COMBINATION WITH OVERRUNNING
PRECIPITATION COULD BRING A PERIOD OF SNOW SATURDAY MORNING.

STRONG WESTERLY FLOW CONTINUES SATURDAY NIGHT WITH THE HEAVIEST
PRECIPITATION WEST OF THE CASCADES, BUT SNOW LEVELS WILL JUMP UP TO
AROUND 7000 FEET SATURDAY AFTERNOON AND REMAIN HIGH SATURDAY NIGHT.
-PETRUCELLI

LONG-TERM FORECAST...SUNDAY THROUGH WEDNESDAY.  A BROAD LONG WAVE
RIDGE WILL BE IN PLACE AT THE BEGINNING OF THE EXTENDED PERIOD WITH
WITH GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP
OF THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL
REMAIN IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE
ZONAL TUESDAY.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL. THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND WILL BE OVER THE CWA SUNDAY. REINFORCING SHORT WAVES
WILL KEEP THE PRECIPITATION GOING THROUGH MOST OF MONDAY. THE BULK
OF THE ASSOCIATED PRECIPITATION WILL FALL ALONG THE COAST...COAST
RANGE...AND UMPQUA BASIN. AMOUNTS WILL BE SIGNIFICANT BUT NOT
EXCESSIVE...NO FLOODING PROBLEMS ARE ANTICIPATED. SNOW LEVELS WILL
BE ABOVE 7000 FEET.

MONDAY NIGHT INTO TUESDAY LOOK TO BE MOSTLY DRY WITH NEARLY ALL THE
ACTION TO THE NORTH OF THE AREA.

THE RIDGE WILL BREAK DOWN WEDNESDAY AND A LONG WAVE TROUGH WILL
BEGIN TO DIG OFFSHORE.  THIS CHANGE IN PATTERN WILL SUPPORT A FRONT
MOVING ONSHORE WEDNESDAY. THIS WILL BE THE WETTEST SYSTEM OF THE
EXTENDED PERIOD IF THE CURRENT EC/GFS MODEL SOLUTIONS PAN OUT. SNOW
LEVELS MAY ALSO FALL AS LOW AS 4000 FEET BEHIND THE FRONT WEDNESDAY
NIGHT...SO SNOW MAY RETURN TO THE PASSES AROUND THAT TIME. -JRS


&&

.AVIATION...BASED ON THE 17/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY WITH AREAS OF HIGHER TERRAIN OBSCURED...EXCEPT FOR
WESTERN AND SOUTH CENTRAL SISKIYOU COUNTY...WHERE AREAS OF MVFR CIGS
WILL PREVAIL THROUGH THURSDAY MORNING.  WIDESPREAD MVFR CIGS AND
AREAS OF IFR CIGS/VSBYS WILL RETURN TO THE WEST SIDE TONIGHT. KOTH
WILL BE AFFECTED BY THE MVFR CIGS AND KRBG AND KMFR WILL BE
AFFECTED BY THE IFR CIGS/VSBYS. ALL AREAS WILL CLEAR TO VFR BY
THURSDAY AFTERNOON. -JRS


&&

.MARINE...UPDATED 935 AM PST WED DEC 17 2014...WEAK LOW PRESSURE
SYSTEMS WILL MOVE THROUGH THE AREA TODAY AND TONIGHT. SOUTHWEST
SWELL DOMINATED SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY.
THURSDAY INTO THURSDAY NIGHT A STRONGER FRONTAL SYSTEM WILL LIKELY
BRING GALE FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. HEAVY WEST
SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY MORNING. IT
WILL PEAK FRIDAY NIGHT AT AROUND 19 FEET AT 18 SECONDS. A WARM FRONT
WILL MOVE THROUGH FRIDAY NIGHT...FOLLOWED BY A COLD FRONT SATURDAY.
OFFSHORE HIGH PRESSURE WILL BUILD SATURDAY NIGHT INTO SUNDAY. -JRS


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.

$$




000
FXUS65 KBOI 172144
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
244 PM MST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS WILL SPREAD FROM EASTERN OREGON INTO THE
CENTRAL IDAHO MOUNTAINS TONIGHT. ON THURSDAY SNOW SHOWERS WILL
CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS WITH VFR CONDITIONS
ELSEWHERE UNDER MOSTLY CLOUDY SKIES. SURFACE WINDS...EAST TO SOUTH 5-
10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K FT MSL.


&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...SP
LONG TERM....JT/AB
AVIATION.....JT



000
FXUS65 KBOI 172144
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
244 PM MST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS WILL SPREAD FROM EASTERN OREGON INTO THE
CENTRAL IDAHO MOUNTAINS TONIGHT. ON THURSDAY SNOW SHOWERS WILL
CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS WITH VFR CONDITIONS
ELSEWHERE UNDER MOSTLY CLOUDY SKIES. SURFACE WINDS...EAST TO SOUTH 5-
10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K FT MSL.


&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...SP
LONG TERM....JT/AB
AVIATION.....JT



000
FXUS65 KBOI 172144
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
244 PM MST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS WILL SPREAD FROM EASTERN OREGON INTO THE
CENTRAL IDAHO MOUNTAINS TONIGHT. ON THURSDAY SNOW SHOWERS WILL
CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS WITH VFR CONDITIONS
ELSEWHERE UNDER MOSTLY CLOUDY SKIES. SURFACE WINDS...EAST TO SOUTH 5-
10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K FT MSL.


&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...SP
LONG TERM....JT/AB
AVIATION.....JT



000
FXUS65 KBOI 172144
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
244 PM MST WED DEC 17 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A WEAK SHORT WAVE TROUGH
WILL MOVE THROUGH OVERNIGHT...SPREADING LIGHT SHOWERS MAINLY INTO
HARNEY COUNTY THIS EVENING...AND THE HIGHER TERRAIN OF THE NORTH
AFTER MIDNIGHT. A WEAK RIDGE AXIS WILL THEN QUICKLY FOLLOW THU AND
THU NIGHT. ON FRIDAY...THE REGION WILL SEE INCREASING MOISTURE AS
SW FLOW ALOFT IS REESTABLISHED IN ADVANCE OF A STRONG MOIST JET
MOVING IN FROM THE PACIFIC. ONE ROUND OF PRECIPITATION WILL MOVE
THROUGH DURING THE DAY FRIDAY...WITH THE BULK IN ERN OREGON IN THE
MORNING AND IN SW IDAHO IN THE AFTERNOON. HOWEVER...SHOWERS ARE
POSSIBLE IN ALL AREAS MOST OF THE DAY. SEVERAL INCHES OF SNOW ARE
LIKELY ABOVE 3500 TO 4000 FEET. TEMPS WILL CONTINUE TO BE ABOVE
NORMAL...WITH LIGHT WINDS AND MOSTLY CLOUDY SKIES LASTING THROUGH
THE SHORT TERM. FRIDAY MORNING RAIN MAY MIX WITH SNOW IN THE
TREASURE VALLEY...BUT TEMPS ARE EXPECTED TO BE JUST ABOVE FREEZING
SO TRAVEL PROBLEMS SHOULD BE MINIMAL.

.LONG TERM...FRIDAY NIGHT THROUGH MONDAY...MODELS CONTINUE IN
GOOD AGREEMENT THROUGH MONDAY. MILD ZONAL FLOW WILL BRING A WEAK
DISTURBANCE ACROSS OUR CWA FRIDAY NIGHT WITH MAINLY LIGHT
PRECIPITATION AND SNOW LEVELS AROUND 4000 FEET. SATURDAY THROUGH
SUNDAY THE UPPER LEVEL FLOW WILL BECOME MORE NORTHWESTERLY COMING
AROUND AN UPPER LEVEL RIDGE BUILDING OFF THE CALIFORNIA COAST.
THIS WILL PATTERN WILL TRANSPORT SLIGHTLY WARMER AIR INTO OUR
AREA...ALONG WITH ABUNDANT MOISTURE FOR MODERATE AMOUNTS OF
PRECIPITATION AT ALL ELEVATIONS...MOSTLY FALLING SATURDAY NIGHT
AND SUNDAY MORNING. SNOW LEVELS SATURDAY NIGHT WILL RANGE FROM
4000 FEET IN THE NORTH TO 5000 FEET ALONG THE NEVADA BORDER. ON
SUNDAY SNOW LEVELS WILL RISE CONSIDERABLY...RANGING FROM 5500 FEET
IN THE CENTRAL IDAHO MOUNTAINS TO 8000 FEET IN SOUTHEAST OREGON.
SNOW ACCUMULATIONS OF 6 TO 12 INCHES ARE POSSIBLE IN THE CENTRAL
IDAHO MOUNTAINS ABOVE 5500 FEET BY SUNDAY NIGHT. A CHANCE OF SNOW
WILL CONTINUE OVER THE MOUNTAINS THROUGH MONDAY...WITH A CHANCE OF
RAIN SHOWERS BELOW 6000 FEET. TEMPERATURES WILL REMAIN ABOVE
NORMAL BY 5 TO 15 DEGREES...WITH MONDAY THE WARMEST DAY.

MONDAY NIGHT THROUGH WEDNESDAY...THE REGION WILL BE UNDER THE
INFLUENCE OF A NORTHWEST FLOW WHICH WILL CARRY ENOUGH MOISTURE TO
BRING A CHANCE OF PRECIPITATION TO THE WEST CENTRAL AND BOISE
MOUNTAINS. BY WEDNESDAY AFTERNOON...A SHORTWAVE WILL MOVE INTO THE
REGION FROM THE WEST BRINGING PRECIPITATION TO MOST OF SOUTHEAST
OREGON AND SOUTHWEST IDAHO. TEMPERATURES WILL REMAIN 5-10 DEGREES
ABOVE NORMAL AND WILL COOL SLIGHTLY WITH THE SHORTWAVE. SNOW LEVELS
WILL DROP AS WELL...COMING DOWN TO ABOUT 3000 TO 3500 FEET IN THE
BLUE/WEST CENTRAL/BOISE MOUNTAINS BY WEDNESDAY NIGHT...ALLOWING
PRECIPITATION TO COME IN THE FORM OF SNOW.

&&

.AVIATION...SCATTERED SNOW SHOWERS WITH AREAS OF MVFR CEILINGS AND
LOCAL IFR CONDITIONS WILL SPREAD FROM EASTERN OREGON INTO THE
CENTRAL IDAHO MOUNTAINS TONIGHT. ON THURSDAY SNOW SHOWERS WILL
CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS WITH VFR CONDITIONS
ELSEWHERE UNDER MOSTLY CLOUDY SKIES. SURFACE WINDS...EAST TO SOUTH 5-
10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K FT MSL.


&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...SP
LONG TERM....JT/AB
AVIATION.....JT



000
FXUS66 KPQR 171756
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
954 AM PST WED DEC 17 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND EVENTUALLY MOVE ONSHORE ALONG THE N OR/S WA COAST
THIS AFTERNOON. THIS WILL MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY
OVER THE HIGHER TERRAIN THIS MORNING. AN UPPER LEVEL SHORTWAVE WILL
PUSH ONSHORE LATER TODAY...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST AND RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.UPDATE...SUBTLE CHANGES FOR TODAY MAINLY BY INCREASING POPS FOR THE
AFTERNOON...AND LATE AFTERNOON PROBABLY IN REALITY. ALSO PLAN ON
RAMPING UP COAST RANGE AND CASCADE WINDS FOR THE NEXT FRONTAL SYSTEM
MAINLY LATE THURSDAY AFTERNOON AND THURSDAY NIGHT. NOT ANTICIPATING
ANY HIGHLIGHTS BUT PROBABLY A RUN OF THE MILL WINDY COASTAL STORM.

MAIN ATTENTION WILL BE PLACED ON THE ATMOSPHERIC RIVER EVENT SETTING
UP TO AFFECT THE REGION THIS WEEKEND WITH IMPACTS LASTING INTO NEXT
WEEK. RAW GFS MODEL RUN ACCUMULATED QPF AMOUNTS EXCEED 12 INCHES FOR
PORTIONS OF THE CASCADES AND 10 INCHES FOR THE COAST RANGE ENDING
MONDAY MORNING. MOST OF THAT OCCURS BEGINNING SATURDAY. THERE WOULD
BE DEEP WESTERLY FLOW FROM THE SURFACE UP TO THE JET LEVEL THUS
EXPECT THIS COULD BE AN IDEAL SITUATION TO EXTRACT A MAXIMUM AMOUNT
OF RAIN FROM WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE
SUPPORT FROM THE ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS
FOLLOWING THE HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT
REALITY BRINGS SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL
RUNS STAY UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM
RIVERS EXCEEDING FLOOD STAGE AS SOON AS SUNDAY MORNING.

WILL BEGIN TO ISSUE SOME OUTLOOK PRODUCTS TODAY WITH THE CAVEAT THAT
MODELS HAVE RELATIVELY RECENTLY SHIFTED THE FOCUS FROM NORTHERN
WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA. ADDITIONAL SHIFTING
IS EXPECTED AS WELL AS TIMING DIFFERENCES. STAY TUNED AS THIS
SITUATION EVOLVES OVER TIME. /JBONK

&&

.PREV DISC... /ISSUED 259 AM PST WED DEC 17 2014/

SHORT TERM...TODAY THROUGH SATURDAY...VERY LIGHT RAIN CONTINUES TO
IMPACT SW WASHINGTON THIS MORNING BUT HAS OTHERWISE STARTED TO
DISSIPATE OVER THE SOUTHERN PORTION OF THE FORECAST AREA. WATER
VAPOR IMAGERY SHOWS A CLOSED LOW WEAKENING AS IT HAS PUSHED ONSHORE
NEAR THE OREGON/CALIFORNIA BORDER...WHILE AN UPPER LEVEL SHORTWAVE
IS ELONGATING AS IT APPROACHES THE PACIFIC NORTHWEST COASTLINE. NOT
MUCH CHANGE IN THE KTTD-KDLS GRADIENT...WHICH REMAINS AROUND -5
EARLY THIS MORNING. EAST WINDS CONTINUE TO GUST NEAR 25 MPH THROUGH
THE GORGE...BUT EXPECT THE EASTERLY GRADIENT TO WEAKEN BY LATE
TONIGHT.

AFTER A PERIOD OF LIGHT RAIN THIS MORNING...MODELS REMAIN CONSISTENT
IN SHOWING AN UPTICK IN PRECIP BY THIS AFTERNOON ASSOCIATED WITH THE
VORT MAX JUST OFFSHORE AROUND 45N 134W. THE LOWER LEVEL MOISTURE
ASSOCIATED WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING
FROM THE SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP THIS
EVENING AND THROUGH TONIGHT. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY.

WITH CLEARING SKIES AND LIGHT WINDS...SHOULD SEE SOME SHALLOW FOG TO
DEVELOP IN INTERIOR VALLEYS TONIGHT THROUGH EARLY THU MORNING. MODELS
MAINTAIN A THREAT FOR LIGHT PRECIP OVER THE HIGHER TERRAIN MUCH OF
THU...BUT OTHERWISE EXPECT DRY CONDITIONS TO PERSIST TO LOWER
ELEVATIONS. THE NEXT SIGNIFICANT FRONTAL SYSTEM ARRIVES LATE
THU...SPREADING RAIN AND BRINGING GUSTY COASTAL WINDS TO THE REGION
THROUGH FRI. PRECIPITABLE WATER IS EXPECTED TO BE NEAR AN INCH AND AN
APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND EXPECT THE
HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE COAST AND COAST
RANGE THROUGH MIDDAY FRI. OTHER LOCATIONS WILL SEE ON AVERAGE 0.5
INCHES OF RAIN. SNOW LEVELS SHOULD REMAIN ABOVE 5000 FEET DURING THE
PEAK RAIN PERIOD...BUT LOWER TO NEAR OR BELOW THE CASCADE PASSES
BEHIND THE FRONT FRIDAY AFTERNOON.

STRONG LOW PRESSURE OVER THE GULF OF ALASKA WILL PUSH INLAND LATE FRI
INTO EARLY SAT MORNING...SIMULTANEOUSLY FLATTENING A BROAD AREA OF
HIGH PRESSURE OVER THE EASTERN PACIFIC. THERE IS INCREASING
CONFIDENCE AN ATMOSPHERIC RIVER SCENARIO WILL SET UP...WITH ABUNDANT
MOISTURE AIMED DIRECTLY AT THE PACIFIC NORTHWEST SAT.

LONG TERM...SATURDAY NIGHT THROUGH TUESDAY...AS THIS TROUGH MOVES ON
SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES ONSHORE AND STALLS
EAST-TO-WEST ACROSS NORTHWEST OREGON AND SOUTHWEST WASHINGTON. THIS
PUTS OUR AREA IN THE PATH OF RAIN STARTING SATURDAY THROUGH MONDAY.
SOME UNCERTAINTY EXISTS IN WHERE THIS BOUNDARY WILL SET UP...WHICH
WILL DETERMINE HOW MUCH RAINFALL WE WILL GET. ON TUESDAY...GEFS
ENSEMBLE SPAGHETTI PLOTS GET MESSY AND SIGNIFICANT DIFFERENCES START
TO SHOW UP BETWEEN THE GFS AND ECMWF...DECREASING CONFIDENCE ON HOW
THE REST OF THE WEEK WILL SHAPE UP.  AS OF NOW...THE MOST COMMON
SOLUTION IS THAT HIGH PRESSURE RIDGING WILL START TO BUILD BACK OVER
THE WESTERN U.S. WHICH SUGGESTS DRIER WEATHER STARTING TUESDAY...
THOUGH UNCERTAINTY IS VERY HIGH. -MCCOY

&&

.AVIATION...VFR CONDITIONS TO PERSIST AT MOST TAF SITES THROUGH
THIS AFTERNOON. AS SHOWERS MOVE IN...THERE MAY BE PERIODS OF
MVFR...ESPECIALLY AT SOUTH WILLAMETTE VALLEY SITES. CLEARING IS
POSSIBLE THIS EVENING...ALLOWING FOG TO DEVELOP IFR CIGS AND
VIS...BUT UNCERTAINTY IS HIGH BECAUSE THE MODELS ARE HINTING AT A
WEAK LOW PRESSURE SYSTEM OFF THE SOUTH OREGON COAST MOVING INLAND
THIS EVENING. THIS COULD BRING ADDITIONAL SHOWERS AND WINDS WHICH
WOULD KEEP CIGS VFR/MVFR. IF ANY CLEARING DOES OCCUR...EXPECT CIGS
AND VIS TO DROP TO IFR WITH THE DEVELOPMENT OF FOG/LOW STRATUS.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST WEDNESDAY.
RAIN MAY BRING PERIODS OF MVFR CIGS AND VIS. CIGS COULD DROP TO
IFR TONIGHT WITH THE DEVELOPMENT OF FOG/LOW STRATUS AFTER 09Z
THURSDAY. -MCCOY

&&

.MARINE...WEST SWELL AROUND 10 FT BRINGING SEAS UP TO SMALL CRAFT
CRITERIA TODAY. SEAS DROP BELOW 10 FT LATER THIS EVENING. THE
SYSTEM OF INTEREST WILL BE TOMORROW WHICH WILL LIKELY BRING
SOUTHERLY GALES THROUGH EARLY FRIDAY. THERE IS STILL SOME
UNCERTAINTY ON TIMING...BUT MODELS ARE COMING INTO AGREEMENT THAT
WINDS WILL START TO INCREASE EARLY THURSDAY MORNING...REACHING
GALE FORCE BY EARLY AFTERNOON. SEAS BUILD INTO THE TEENS THURSDAY
AFTERNOON. SEAS DROP BACK DOWN TO 10 TO 12 FT ON FRIDAY AHEAD OF
THE NEXT SYSTEM WHICH WILL BRING SEAS UP EVEN HIGHER ON SATURDAY.

THERE IS STILL UNCERTAINTY ON THE TIMING OF THE SATURDAY SYSTEM...BUT
AS OF NOW MODELS ARE SUGGESTING THAT WINDS COULD AGAIN REACH GALE
FORCE EARLY SATURDAY...WHICH COULD BUILD SEAS INTO THE LOW 20S.
SEAS START TO FALL EARLY SUNDAY...DROPPING BACK INTO THE LOW
TEENS BY LATE SUNDAY OR EARLY MONDAY. AN ACTIVE WEATHER PATTERN
WILL CONTINUE THROUGH THIS WEEKEND...KEEPING SEAS ELEVATED
THROUGH EARLY NEXT WEEK WITH PERIODS OF GALES POSSIBLE. -MCCOY


&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 PM PST THIS AFTERNOON.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 171756
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
954 AM PST WED DEC 17 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND EVENTUALLY MOVE ONSHORE ALONG THE N OR/S WA COAST
THIS AFTERNOON. THIS WILL MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY
OVER THE HIGHER TERRAIN THIS MORNING. AN UPPER LEVEL SHORTWAVE WILL
PUSH ONSHORE LATER TODAY...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST AND RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.UPDATE...SUBTLE CHANGES FOR TODAY MAINLY BY INCREASING POPS FOR THE
AFTERNOON...AND LATE AFTERNOON PROBABLY IN REALITY. ALSO PLAN ON
RAMPING UP COAST RANGE AND CASCADE WINDS FOR THE NEXT FRONTAL SYSTEM
MAINLY LATE THURSDAY AFTERNOON AND THURSDAY NIGHT. NOT ANTICIPATING
ANY HIGHLIGHTS BUT PROBABLY A RUN OF THE MILL WINDY COASTAL STORM.

MAIN ATTENTION WILL BE PLACED ON THE ATMOSPHERIC RIVER EVENT SETTING
UP TO AFFECT THE REGION THIS WEEKEND WITH IMPACTS LASTING INTO NEXT
WEEK. RAW GFS MODEL RUN ACCUMULATED QPF AMOUNTS EXCEED 12 INCHES FOR
PORTIONS OF THE CASCADES AND 10 INCHES FOR THE COAST RANGE ENDING
MONDAY MORNING. MOST OF THAT OCCURS BEGINNING SATURDAY. THERE WOULD
BE DEEP WESTERLY FLOW FROM THE SURFACE UP TO THE JET LEVEL THUS
EXPECT THIS COULD BE AN IDEAL SITUATION TO EXTRACT A MAXIMUM AMOUNT
OF RAIN FROM WHATEVER COMES ASHORE. THERE IS GENERAL LARGE SCALE
SUPPORT FROM THE ECMWF ALBEIT WITH LESS QPF. PAST EXPERIENCE SHOWS
FOLLOWING THE HIGHER GFS QPF AMOUNTS IS STILL NOT ENOUGH AND THAT
REALITY BRINGS SIGNIFICANTLY MORE RAIN. ASSUMING THE CURRENT MODEL
RUNS STAY UNCHANGED IN THE FUTURE...WOULD EXPECT MULTIPLE MAINSTEM
RIVERS EXCEEDING FLOOD STAGE AS SOON AS SUNDAY MORNING.

WILL BEGIN TO ISSUE SOME OUTLOOK PRODUCTS TODAY WITH THE CAVEAT THAT
MODELS HAVE RELATIVELY RECENTLY SHIFTED THE FOCUS FROM NORTHERN
WASHINGTON/BRITISH COLUMBIA SOUTH TO OUR AREA. ADDITIONAL SHIFTING
IS EXPECTED AS WELL AS TIMING DIFFERENCES. STAY TUNED AS THIS
SITUATION EVOLVES OVER TIME. /JBONK

&&

.PREV DISC... /ISSUED 259 AM PST WED DEC 17 2014/

SHORT TERM...TODAY THROUGH SATURDAY...VERY LIGHT RAIN CONTINUES TO
IMPACT SW WASHINGTON THIS MORNING BUT HAS OTHERWISE STARTED TO
DISSIPATE OVER THE SOUTHERN PORTION OF THE FORECAST AREA. WATER
VAPOR IMAGERY SHOWS A CLOSED LOW WEAKENING AS IT HAS PUSHED ONSHORE
NEAR THE OREGON/CALIFORNIA BORDER...WHILE AN UPPER LEVEL SHORTWAVE
IS ELONGATING AS IT APPROACHES THE PACIFIC NORTHWEST COASTLINE. NOT
MUCH CHANGE IN THE KTTD-KDLS GRADIENT...WHICH REMAINS AROUND -5
EARLY THIS MORNING. EAST WINDS CONTINUE TO GUST NEAR 25 MPH THROUGH
THE GORGE...BUT EXPECT THE EASTERLY GRADIENT TO WEAKEN BY LATE
TONIGHT.

AFTER A PERIOD OF LIGHT RAIN THIS MORNING...MODELS REMAIN CONSISTENT
IN SHOWING AN UPTICK IN PRECIP BY THIS AFTERNOON ASSOCIATED WITH THE
VORT MAX JUST OFFSHORE AROUND 45N 134W. THE LOWER LEVEL MOISTURE
ASSOCIATED WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING
FROM THE SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP THIS
EVENING AND THROUGH TONIGHT. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY.

WITH CLEARING SKIES AND LIGHT WINDS...SHOULD SEE SOME SHALLOW FOG TO
DEVELOP IN INTERIOR VALLEYS TONIGHT THROUGH EARLY THU MORNING. MODELS
MAINTAIN A THREAT FOR LIGHT PRECIP OVER THE HIGHER TERRAIN MUCH OF
THU...BUT OTHERWISE EXPECT DRY CONDITIONS TO PERSIST TO LOWER
ELEVATIONS. THE NEXT SIGNIFICANT FRONTAL SYSTEM ARRIVES LATE
THU...SPREADING RAIN AND BRINGING GUSTY COASTAL WINDS TO THE REGION
THROUGH FRI. PRECIPITABLE WATER IS EXPECTED TO BE NEAR AN INCH AND AN
APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND EXPECT THE
HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE COAST AND COAST
RANGE THROUGH MIDDAY FRI. OTHER LOCATIONS WILL SEE ON AVERAGE 0.5
INCHES OF RAIN. SNOW LEVELS SHOULD REMAIN ABOVE 5000 FEET DURING THE
PEAK RAIN PERIOD...BUT LOWER TO NEAR OR BELOW THE CASCADE PASSES
BEHIND THE FRONT FRIDAY AFTERNOON.

STRONG LOW PRESSURE OVER THE GULF OF ALASKA WILL PUSH INLAND LATE FRI
INTO EARLY SAT MORNING...SIMULTANEOUSLY FLATTENING A BROAD AREA OF
HIGH PRESSURE OVER THE EASTERN PACIFIC. THERE IS INCREASING
CONFIDENCE AN ATMOSPHERIC RIVER SCENARIO WILL SET UP...WITH ABUNDANT
MOISTURE AIMED DIRECTLY AT THE PACIFIC NORTHWEST SAT.

LONG TERM...SATURDAY NIGHT THROUGH TUESDAY...AS THIS TROUGH MOVES ON
SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES ONSHORE AND STALLS
EAST-TO-WEST ACROSS NORTHWEST OREGON AND SOUTHWEST WASHINGTON. THIS
PUTS OUR AREA IN THE PATH OF RAIN STARTING SATURDAY THROUGH MONDAY.
SOME UNCERTAINTY EXISTS IN WHERE THIS BOUNDARY WILL SET UP...WHICH
WILL DETERMINE HOW MUCH RAINFALL WE WILL GET. ON TUESDAY...GEFS
ENSEMBLE SPAGHETTI PLOTS GET MESSY AND SIGNIFICANT DIFFERENCES START
TO SHOW UP BETWEEN THE GFS AND ECMWF...DECREASING CONFIDENCE ON HOW
THE REST OF THE WEEK WILL SHAPE UP.  AS OF NOW...THE MOST COMMON
SOLUTION IS THAT HIGH PRESSURE RIDGING WILL START TO BUILD BACK OVER
THE WESTERN U.S. WHICH SUGGESTS DRIER WEATHER STARTING TUESDAY...
THOUGH UNCERTAINTY IS VERY HIGH. -MCCOY

&&

.AVIATION...VFR CONDITIONS TO PERSIST AT MOST TAF SITES THROUGH
THIS AFTERNOON. AS SHOWERS MOVE IN...THERE MAY BE PERIODS OF
MVFR...ESPECIALLY AT SOUTH WILLAMETTE VALLEY SITES. CLEARING IS
POSSIBLE THIS EVENING...ALLOWING FOG TO DEVELOP IFR CIGS AND
VIS...BUT UNCERTAINTY IS HIGH BECAUSE THE MODELS ARE HINTING AT A
WEAK LOW PRESSURE SYSTEM OFF THE SOUTH OREGON COAST MOVING INLAND
THIS EVENING. THIS COULD BRING ADDITIONAL SHOWERS AND WINDS WHICH
WOULD KEEP CIGS VFR/MVFR. IF ANY CLEARING DOES OCCUR...EXPECT CIGS
AND VIS TO DROP TO IFR WITH THE DEVELOPMENT OF FOG/LOW STRATUS.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST WEDNESDAY.
RAIN MAY BRING PERIODS OF MVFR CIGS AND VIS. CIGS COULD DROP TO
IFR TONIGHT WITH THE DEVELOPMENT OF FOG/LOW STRATUS AFTER 09Z
THURSDAY. -MCCOY

&&

.MARINE...WEST SWELL AROUND 10 FT BRINGING SEAS UP TO SMALL CRAFT
CRITERIA TODAY. SEAS DROP BELOW 10 FT LATER THIS EVENING. THE
SYSTEM OF INTEREST WILL BE TOMORROW WHICH WILL LIKELY BRING
SOUTHERLY GALES THROUGH EARLY FRIDAY. THERE IS STILL SOME
UNCERTAINTY ON TIMING...BUT MODELS ARE COMING INTO AGREEMENT THAT
WINDS WILL START TO INCREASE EARLY THURSDAY MORNING...REACHING
GALE FORCE BY EARLY AFTERNOON. SEAS BUILD INTO THE TEENS THURSDAY
AFTERNOON. SEAS DROP BACK DOWN TO 10 TO 12 FT ON FRIDAY AHEAD OF
THE NEXT SYSTEM WHICH WILL BRING SEAS UP EVEN HIGHER ON SATURDAY.

THERE IS STILL UNCERTAINTY ON THE TIMING OF THE SATURDAY SYSTEM...BUT
AS OF NOW MODELS ARE SUGGESTING THAT WINDS COULD AGAIN REACH GALE
FORCE EARLY SATURDAY...WHICH COULD BUILD SEAS INTO THE LOW 20S.
SEAS START TO FALL EARLY SUNDAY...DROPPING BACK INTO THE LOW
TEENS BY LATE SUNDAY OR EARLY MONDAY. AN ACTIVE WEATHER PATTERN
WILL CONTINUE THROUGH THIS WEEKEND...KEEPING SEAS ELEVATED
THROUGH EARLY NEXT WEEK WITH PERIODS OF GALES POSSIBLE. -MCCOY


&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 9 PM PST THIS
     EVENING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 PM PST THIS AFTERNOON.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPDT 171735
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
935 AM PST WED DEC 17 2014

.SHORT TERM...MORNING UPDATE...UPPER TROUGH WILL CONTINUE OVER THE
REGION TODAY. A WEAKENING DISTURBANCE WILL EXIT THE AREA BY NOON,
WHILE A SECOND WEAKENING DISTURBANCE IS NOW REACHING THE COAST. THUS
SLIGHT CHANCE TO CHANCE POPS WILL MOSTLY COVER PRECIP OCCURRENCE
THROUGH TODAY. THE CASCADE CREST AREAS COULD SEE LIKELY POPS.
OVERALL FORECAST PACKAGE COVERED THESE POPS AND ONLY MADE SOME MINOR
ADJUSTMENTS. DENSE FOG AND FREEZING FOG CONTINUES WHERE THE STRATUS
DECK ACROSS THE BASIN INTERSECTS THE TERRAIN, GENERALLY BETWEEN 1200
AND 3000 FEET MSL. CURRENT ADVISORIES EXPIRE AT 10 AM AND SOME MAY
HAVE TO BE EXTENDED. ALSO MAY HAVE TO CONTINUE SOME OF THESE
ADVISORIES INTO TONIGHT. WINDS CONTINUE TO BE 10 MPH OR LESS EXCEPT
IN THE SOUTHERN GRANDE RONDE VALLEY WHERE THEY WILL RUN 20 TO 30 MPH
FROM THE SOUTH. 90

.LONG TERM...PREVIOUS DISCUSSION...LATEST MODEL GUIDANCE CONTINUES
TO SHOW AN ACTIVE WEATHER PATTERN DURING THE FORECAST PERIOD. A
SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY NIGHT THRU EARLY
SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO THE HIGHER
ELEVATIONS OF THE CWA. THE MAJOR HIGHLIGHT TO THE LONG TERM IS A
CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN IMPRESSIVE 150 KT
JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE WASHINGTON
STATE/OREGON AREA SATURDAY THRU MONDAY. PRECIPITATION CHANCES
INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT THROUGH
MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE AGREEMENT IS HIGH.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL. THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA. THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES. HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY. BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES. TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.

&&

.AVIATION...18Z TAFS...WIDESPREAD IFR/LIFR CONDITIONS IN STRATUS AND
FOG ARE EXPECTED THROUGH 18Z THURSDAY. THERE COULD BE A LITTLE RAIN
AT TIMES ESPECIALLY AT THE WESTERN TAF SITES. KPDT/KALW/KRDM ARE
LIKELY TO SEE THE WORST CONDITIONS WITH VISIBILITIES AS LOW AS 1/4
MILE AT TIMES AND CIGS AS LOW AS 1-2 HUNDRED FEET AGL. THERE COULD
BE SOME IMPROVEMENT IN CIGS AND VSBYS TEMPORARILY THIS AFTERNOON AND
EVENING AREAWIDE BEFORE CONDITIONS DETERIORATE AGAIN OVERNIGHT.
WINDS WILL BE LIGHT. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  33  42  36 /  20  30  10  30
ALW  38  34  42  37 /  20  30  10  30
PSC  42  32  40  35 /  20  30  10  40
YKM  39  30  38  33 /  40  30  10  60
HRI  41  33  41  35 /  20  30  10  40
ELN  38  29  37  32 /  50  30  10  60
RDM  39  27  42  32 /  40  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  41  32  40  32 /  30  30  20  30
DLS  43  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/98/78









000
FXUS66 KPDT 171735
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
935 AM PST WED DEC 17 2014

.SHORT TERM...MORNING UPDATE...UPPER TROUGH WILL CONTINUE OVER THE
REGION TODAY. A WEAKENING DISTURBANCE WILL EXIT THE AREA BY NOON,
WHILE A SECOND WEAKENING DISTURBANCE IS NOW REACHING THE COAST. THUS
SLIGHT CHANCE TO CHANCE POPS WILL MOSTLY COVER PRECIP OCCURRENCE
THROUGH TODAY. THE CASCADE CREST AREAS COULD SEE LIKELY POPS.
OVERALL FORECAST PACKAGE COVERED THESE POPS AND ONLY MADE SOME MINOR
ADJUSTMENTS. DENSE FOG AND FREEZING FOG CONTINUES WHERE THE STRATUS
DECK ACROSS THE BASIN INTERSECTS THE TERRAIN, GENERALLY BETWEEN 1200
AND 3000 FEET MSL. CURRENT ADVISORIES EXPIRE AT 10 AM AND SOME MAY
HAVE TO BE EXTENDED. ALSO MAY HAVE TO CONTINUE SOME OF THESE
ADVISORIES INTO TONIGHT. WINDS CONTINUE TO BE 10 MPH OR LESS EXCEPT
IN THE SOUTHERN GRANDE RONDE VALLEY WHERE THEY WILL RUN 20 TO 30 MPH
FROM THE SOUTH. 90

.LONG TERM...PREVIOUS DISCUSSION...LATEST MODEL GUIDANCE CONTINUES
TO SHOW AN ACTIVE WEATHER PATTERN DURING THE FORECAST PERIOD. A
SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY NIGHT THRU EARLY
SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO THE HIGHER
ELEVATIONS OF THE CWA. THE MAJOR HIGHLIGHT TO THE LONG TERM IS A
CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN IMPRESSIVE 150 KT
JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE WASHINGTON
STATE/OREGON AREA SATURDAY THRU MONDAY. PRECIPITATION CHANCES
INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT THROUGH
MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE AGREEMENT IS HIGH.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL. THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA. THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES. HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY. BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES. TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.

&&

.AVIATION...18Z TAFS...WIDESPREAD IFR/LIFR CONDITIONS IN STRATUS AND
FOG ARE EXPECTED THROUGH 18Z THURSDAY. THERE COULD BE A LITTLE RAIN
AT TIMES ESPECIALLY AT THE WESTERN TAF SITES. KPDT/KALW/KRDM ARE
LIKELY TO SEE THE WORST CONDITIONS WITH VISIBILITIES AS LOW AS 1/4
MILE AT TIMES AND CIGS AS LOW AS 1-2 HUNDRED FEET AGL. THERE COULD
BE SOME IMPROVEMENT IN CIGS AND VSBYS TEMPORARILY THIS AFTERNOON AND
EVENING AREAWIDE BEFORE CONDITIONS DETERIORATE AGAIN OVERNIGHT.
WINDS WILL BE LIGHT. 78

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  33  42  36 /  20  30  10  30
ALW  38  34  42  37 /  20  30  10  30
PSC  42  32  40  35 /  20  30  10  40
YKM  39  30  38  33 /  40  30  10  60
HRI  41  33  41  35 /  20  30  10  40
ELN  38  29  37  32 /  50  30  10  60
RDM  39  27  42  32 /  40  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  41  32  40  32 /  30  30  20  30
DLS  43  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

90/98/78








000
FXUS66 KMFR 171646
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
846 AM PST WED DEC 17 2014

.DISCUSSION...A WEAK TROUGH IS MOVING EAST OF THE AREA THIS
MORNING, BUT ANOTHER WEAK TROUGH WILL QUICKLY ARRIVE THIS
AFTERNOON AND COULD BRING INCREASING PRECIPITATION MAINLY WEST OF
THE CASCADES. THUS HAVE INCREASED POPS AND QPF AMOUNTS FOR THIS
AFTERNOON. THIS TROUGH WILL WEAKEN AS IT MOVES INLAND THIS EVENING
WITH WEAK RIDGING MOVING IN LATE TONIGHT INTO THURSDAY GIVING US A
RELATIVE BREAK IN THE WEATHER. AS MENTIONED IN THE PREVIOUS
DISCUSSION, THIS WILL BE BRIEF WITH THE NEXT FRONT ALREADY ON THE
HEALS OF THE RIDGE WITH PRECIPIATION REACHING THE COAST AS EARLY
AS THURSDAY AFTERNOON.

THE SNOW ADVISORY IS DUE TO EXPIRE AT 10 AM PST. A LOOK AT THE
CAMS SHOW AT LEAST A FEW INCHES AT SNOWMANS SUMMIT, OTHERWISE
THERE WAS NOT ENOUGH COLD AIR AND PRECIPIATION WAS NOT HEAVY
ENOUGH TO DRAG THE SNOW LEVEL DOWN LOW ENOUGH FOR MOUNT SHASTA GO
GET MEASURABLE SNOW. A LOOK AT THE OBS FROM LAST NIGHT SHOWED A
RAIN WET SNOW MIX, BUT PRECIP WAS NOT HEAVY ENOUGH FOR IT TO
CHANGE OVER TO ALL SNOW.

ONE ITEM WE`LL LOOK AT THIS MORNING IS THE POTENTIAL FOR SNOW EAST
OF THE CASCADES SATURDAY MORNING AS A WARM FRONT MOVES INTO THE
AREA. MODEL SOUNDINGS SUGGEST ENOUGH COLD AIR WILL BE PRESENT NEAR
THE SURFACE AND THIS IN COMBINATION WITH OVERRUNNING PRECIPIATION
COULD BRING A PERIOD OF SNOW SATURDAY MORNING. -PETRUCELLI


&&

.AVIATION...MOSTLY VFR CONDITIONS EXIST THIS MORNING, THOUGH
AREAS OF LIFR FOG HAVE FORMED IN THE UMPQUA BASIN. EXPECT THAT
THIS LIFR WILL IMPROVE TO ONLY IFR TO MVFR IN THE UMPQUA BASIN
THIS AFTERNOON, WITH CONDITIONS LOWERING TO MVFR FOR MOST INLAND
LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT TERRAIN OBSCURATIONS TO
BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE INTERIOR WEST SIDE
THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF THIS EVENING.
IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM ACROSS THE
VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL


&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...WEAKENING SURFACE LOW
PRESSURE MOVING NORTHEASTWARD ACROSS THE COASTAL WATERS THIS MORNING
WILL BE FOLLOWED BY ANOTHER LOW PRESSURE SYSTEM APPROACHING FROM THE
WEST. THIS WILL RESULT IN A SURGE OF WEST WINDS THIS MORNING INTO
EARLY AFTERNOON. SOUTHWEST SEAS WILL REMAIN MOSTLY AT OR ABOVE 10
FEET TODAY. THURSDAY INTO THURSDAY NIGHT A STRONGER FRONTAL SYSTEM
IS LIKELY TO CAUSE GALE FORCE WINDS AND VERY STEEP SOUTHWEST SEAS.
FORERUNNERS OF VERY LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE
PREDAWN HOURS FRIDAY MORNING. THIS VERY LARGE WEST SWELL WILL BUILD
FRIDAY, LIKELY PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS.
BTL


&&

.PREV DISCUSSION... /ISSUED 540 AM PST WED DEC 17 2014/

DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON FOR
     PZZ376.

$$



000
FXUS66 KMFR 171646
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
846 AM PST WED DEC 17 2014

.DISCUSSION...A WEAK TROUGH IS MOVING EAST OF THE AREA THIS
MORNING, BUT ANOTHER WEAK TROUGH WILL QUICKLY ARRIVE THIS
AFTERNOON AND COULD BRING INCREASING PRECIPITATION MAINLY WEST OF
THE CASCADES. THUS HAVE INCREASED POPS AND QPF AMOUNTS FOR THIS
AFTERNOON. THIS TROUGH WILL WEAKEN AS IT MOVES INLAND THIS EVENING
WITH WEAK RIDGING MOVING IN LATE TONIGHT INTO THURSDAY GIVING US A
RELATIVE BREAK IN THE WEATHER. AS MENTIONED IN THE PREVIOUS
DISCUSSION, THIS WILL BE BRIEF WITH THE NEXT FRONT ALREADY ON THE
HEALS OF THE RIDGE WITH PRECIPIATION REACHING THE COAST AS EARLY
AS THURSDAY AFTERNOON.

THE SNOW ADVISORY IS DUE TO EXPIRE AT 10 AM PST. A LOOK AT THE
CAMS SHOW AT LEAST A FEW INCHES AT SNOWMANS SUMMIT, OTHERWISE
THERE WAS NOT ENOUGH COLD AIR AND PRECIPIATION WAS NOT HEAVY
ENOUGH TO DRAG THE SNOW LEVEL DOWN LOW ENOUGH FOR MOUNT SHASTA GO
GET MEASURABLE SNOW. A LOOK AT THE OBS FROM LAST NIGHT SHOWED A
RAIN WET SNOW MIX, BUT PRECIP WAS NOT HEAVY ENOUGH FOR IT TO
CHANGE OVER TO ALL SNOW.

ONE ITEM WE`LL LOOK AT THIS MORNING IS THE POTENTIAL FOR SNOW EAST
OF THE CASCADES SATURDAY MORNING AS A WARM FRONT MOVES INTO THE
AREA. MODEL SOUNDINGS SUGGEST ENOUGH COLD AIR WILL BE PRESENT NEAR
THE SURFACE AND THIS IN COMBINATION WITH OVERRUNNING PRECIPIATION
COULD BRING A PERIOD OF SNOW SATURDAY MORNING. -PETRUCELLI


&&

.AVIATION...MOSTLY VFR CONDITIONS EXIST THIS MORNING, THOUGH
AREAS OF LIFR FOG HAVE FORMED IN THE UMPQUA BASIN. EXPECT THAT
THIS LIFR WILL IMPROVE TO ONLY IFR TO MVFR IN THE UMPQUA BASIN
THIS AFTERNOON, WITH CONDITIONS LOWERING TO MVFR FOR MOST INLAND
LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT TERRAIN OBSCURATIONS TO
BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE INTERIOR WEST SIDE
THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF THIS EVENING.
IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM ACROSS THE
VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL


&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...WEAKENING SURFACE LOW
PRESSURE MOVING NORTHEASTWARD ACROSS THE COASTAL WATERS THIS MORNING
WILL BE FOLLOWED BY ANOTHER LOW PRESSURE SYSTEM APPROACHING FROM THE
WEST. THIS WILL RESULT IN A SURGE OF WEST WINDS THIS MORNING INTO
EARLY AFTERNOON. SOUTHWEST SEAS WILL REMAIN MOSTLY AT OR ABOVE 10
FEET TODAY. THURSDAY INTO THURSDAY NIGHT A STRONGER FRONTAL SYSTEM
IS LIKELY TO CAUSE GALE FORCE WINDS AND VERY STEEP SOUTHWEST SEAS.
FORERUNNERS OF VERY LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE
PREDAWN HOURS FRIDAY MORNING. THIS VERY LARGE WEST SWELL WILL BUILD
FRIDAY, LIKELY PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS.
BTL


&&

.PREV DISCUSSION... /ISSUED 540 AM PST WED DEC 17 2014/

DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON FOR
     PZZ376.

$$




000
FXUS65 KBOI 171644
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
944 AM MST WED DEC 17 2014

.DISCUSSION...MOSTLY CLOUDY TODAY IN SE OREGON...THE LOWER
TREASURE VALLEY...AND THE MTNS OF SW IDAHO...WITH SOME CLEARING
IN OWYHEE COUNTY AND THE UPPER TREASURE VALLEY. CLOUDS WILL
CONTINUE TO PASS OVER THE REGION TODAY AS A WEAK UPPER LEVEL SHORT
WAVE TROUGH PROGRESSES SLOWLY EASTWARD. THIS WILL ALSO HELP SPREAD
LIGHT SHOWERS ACROSS MAINLY THE MTNS OF THE NORTH AND IN HARNEY
COUNTY. TEMPS WILL RISE TO 5 TO 10 DEGREES ABOVE NORMAL BOTH TODAY
AND TOMORROW. WINDS WILL REMAIN LIGHT. NO CHANGES TO THE FORECAST
THIS MORNING.

&&

.AVIATION...SCATTERED LOCALLY MVFR SNOW SHOWERS WILL DEVELOP OVER
EASTERN OREGON BY THIS AFTERNOON FROM HARNEY COUNTY UP ACROSS BAKER
COUNTY...SPREADING INTO THE CENTRAL IDAHO MOUNTAINS TONIGHT. ON
THURSDAY SNOW SHOWERS WILL DECREASE TO ISOLATED IN EASTERN OREGON
BUT CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS. SURFACE WINDS...EAST
TO SOUTH 5-10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K
FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO-DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...SP
AVIATION.....JT
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 171644
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
944 AM MST WED DEC 17 2014

.DISCUSSION...MOSTLY CLOUDY TODAY IN SE OREGON...THE LOWER
TREASURE VALLEY...AND THE MTNS OF SW IDAHO...WITH SOME CLEARING
IN OWYHEE COUNTY AND THE UPPER TREASURE VALLEY. CLOUDS WILL
CONTINUE TO PASS OVER THE REGION TODAY AS A WEAK UPPER LEVEL SHORT
WAVE TROUGH PROGRESSES SLOWLY EASTWARD. THIS WILL ALSO HELP SPREAD
LIGHT SHOWERS ACROSS MAINLY THE MTNS OF THE NORTH AND IN HARNEY
COUNTY. TEMPS WILL RISE TO 5 TO 10 DEGREES ABOVE NORMAL BOTH TODAY
AND TOMORROW. WINDS WILL REMAIN LIGHT. NO CHANGES TO THE FORECAST
THIS MORNING.

&&

.AVIATION...SCATTERED LOCALLY MVFR SNOW SHOWERS WILL DEVELOP OVER
EASTERN OREGON BY THIS AFTERNOON FROM HARNEY COUNTY UP ACROSS BAKER
COUNTY...SPREADING INTO THE CENTRAL IDAHO MOUNTAINS TONIGHT. ON
THURSDAY SNOW SHOWERS WILL DECREASE TO ISOLATED IN EASTERN OREGON
BUT CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS. SURFACE WINDS...EAST
TO SOUTH 5-10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K
FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO-DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...SP
AVIATION.....JT
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 171644
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
944 AM MST WED DEC 17 2014

.DISCUSSION...MOSTLY CLOUDY TODAY IN SE OREGON...THE LOWER
TREASURE VALLEY...AND THE MTNS OF SW IDAHO...WITH SOME CLEARING
IN OWYHEE COUNTY AND THE UPPER TREASURE VALLEY. CLOUDS WILL
CONTINUE TO PASS OVER THE REGION TODAY AS A WEAK UPPER LEVEL SHORT
WAVE TROUGH PROGRESSES SLOWLY EASTWARD. THIS WILL ALSO HELP SPREAD
LIGHT SHOWERS ACROSS MAINLY THE MTNS OF THE NORTH AND IN HARNEY
COUNTY. TEMPS WILL RISE TO 5 TO 10 DEGREES ABOVE NORMAL BOTH TODAY
AND TOMORROW. WINDS WILL REMAIN LIGHT. NO CHANGES TO THE FORECAST
THIS MORNING.

&&

.AVIATION...SCATTERED LOCALLY MVFR SNOW SHOWERS WILL DEVELOP OVER
EASTERN OREGON BY THIS AFTERNOON FROM HARNEY COUNTY UP ACROSS BAKER
COUNTY...SPREADING INTO THE CENTRAL IDAHO MOUNTAINS TONIGHT. ON
THURSDAY SNOW SHOWERS WILL DECREASE TO ISOLATED IN EASTERN OREGON
BUT CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS. SURFACE WINDS...EAST
TO SOUTH 5-10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K
FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO-DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...SP
AVIATION.....JT
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 171644
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
944 AM MST WED DEC 17 2014

.DISCUSSION...MOSTLY CLOUDY TODAY IN SE OREGON...THE LOWER
TREASURE VALLEY...AND THE MTNS OF SW IDAHO...WITH SOME CLEARING
IN OWYHEE COUNTY AND THE UPPER TREASURE VALLEY. CLOUDS WILL
CONTINUE TO PASS OVER THE REGION TODAY AS A WEAK UPPER LEVEL SHORT
WAVE TROUGH PROGRESSES SLOWLY EASTWARD. THIS WILL ALSO HELP SPREAD
LIGHT SHOWERS ACROSS MAINLY THE MTNS OF THE NORTH AND IN HARNEY
COUNTY. TEMPS WILL RISE TO 5 TO 10 DEGREES ABOVE NORMAL BOTH TODAY
AND TOMORROW. WINDS WILL REMAIN LIGHT. NO CHANGES TO THE FORECAST
THIS MORNING.

&&

.AVIATION...SCATTERED LOCALLY MVFR SNOW SHOWERS WILL DEVELOP OVER
EASTERN OREGON BY THIS AFTERNOON FROM HARNEY COUNTY UP ACROSS BAKER
COUNTY...SPREADING INTO THE CENTRAL IDAHO MOUNTAINS TONIGHT. ON
THURSDAY SNOW SHOWERS WILL DECREASE TO ISOLATED IN EASTERN OREGON
BUT CONTINUE OVER THE CENTRAL IDAHO MOUNTAINS. SURFACE WINDS...EAST
TO SOUTH 5-10 KTS. WINDS ALOFT...SOUTHWEST 10-15 KTS UP THROUGH 10K
FT MSL.

&&

.PREV DISCUSSION...
SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO-DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...SP
AVIATION.....JT
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS66 KPDT 171450 AAC
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE AGREEMENT IS
HIGH.  MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT
2 TO 3 STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171450 AAC
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE AGREEMENT IS
HIGH.  MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT
2 TO 3 STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98






000
FXUS66 KMFR 171340
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
540 AM PST WED DEC 17 2014

.DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/12Z TAF CYCLE...
WEAK LOW PRESSURE WILL CONTINUE A GENERAL SOUTH TO SOUTHWEST FLOW
ACROSS THE AREA TODAY, WITH SHOWERS THROUGH THE DAY. THESE SHOWERS
WILL BE MOST NUMEROUS IN THE MOUNT SHASTA AREA, WESTERN SISKIYOU
COUNTY, AND ALONG AND NEAR THE COAST TODAY. FOR INLAND AREAS THE
BEST CHANCE OF PRECIPITATION WILL BE THIS AFTERNOON AND EVENING.
PRECIPITATION WILL BE MOSTLY RAIN BELOW 4KFT ELEVATIONS AND SNOW
ABOVE 5KFT, WITH A MIX FOR ELEVATIONS IN BETWEEN. MOSTLY VFR
CONDITIONS EXIST THIS MORNING, THOUGH AREAS OF LIFR FOG HAVE FORMED
IN THE UMPQUA BASIN. EXPECT THAT THIS LIFR WILL IMPROVE TO ONLY IFR
TO MVFR IN THE UMPQUA BASIN THIS AFTERNOON, WITH CONDITIONS LOWERING
TO MVFR FOR MOST INLAND LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT
TERRAIN OBSCURATIONS TO BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE
INTERIOR WEST SIDE THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF
THIS EVENING. IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM
ACROSS THE VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL

&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...
WEAKENING SURFACE LOW PRESSURE MOVING NORTHEASTWARD ACROSS THE
COASTAL WATERS THIS MORNING WILL BE FOLLOWED BY ANOTHER LOW
PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS WILL RESULT IN A
SURGE OF WEST WINDS THIS MORNING INTO EARLY AFTERNOON. SOUTHWEST
SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY. THURSDAY INTO
THURSDAY NIGHT A STRONGER FRONTAL SYSTEM IS LIKELY TO CAUSE GALE
FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. FORERUNNERS OF VERY
LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY
MORNING. THIS VERY LARGE WEST SWELL WILL BUILD FRIDAY, LIKELY
PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
  PZZ350-356-370-376.
- HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
  THURSDAY NIGHT FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON
  FOR PZZ376.

$$

TRW/BTL



000
FXUS66 KMFR 171340
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
540 AM PST WED DEC 17 2014

.DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/12Z TAF CYCLE...
WEAK LOW PRESSURE WILL CONTINUE A GENERAL SOUTH TO SOUTHWEST FLOW
ACROSS THE AREA TODAY, WITH SHOWERS THROUGH THE DAY. THESE SHOWERS
WILL BE MOST NUMEROUS IN THE MOUNT SHASTA AREA, WESTERN SISKIYOU
COUNTY, AND ALONG AND NEAR THE COAST TODAY. FOR INLAND AREAS THE
BEST CHANCE OF PRECIPITATION WILL BE THIS AFTERNOON AND EVENING.
PRECIPITATION WILL BE MOSTLY RAIN BELOW 4KFT ELEVATIONS AND SNOW
ABOVE 5KFT, WITH A MIX FOR ELEVATIONS IN BETWEEN. MOSTLY VFR
CONDITIONS EXIST THIS MORNING, THOUGH AREAS OF LIFR FOG HAVE FORMED
IN THE UMPQUA BASIN. EXPECT THAT THIS LIFR WILL IMPROVE TO ONLY IFR
TO MVFR IN THE UMPQUA BASIN THIS AFTERNOON, WITH CONDITIONS LOWERING
TO MVFR FOR MOST INLAND LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT
TERRAIN OBSCURATIONS TO BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE
INTERIOR WEST SIDE THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF
THIS EVENING. IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM
ACROSS THE VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL

&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...
WEAKENING SURFACE LOW PRESSURE MOVING NORTHEASTWARD ACROSS THE
COASTAL WATERS THIS MORNING WILL BE FOLLOWED BY ANOTHER LOW
PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS WILL RESULT IN A
SURGE OF WEST WINDS THIS MORNING INTO EARLY AFTERNOON. SOUTHWEST
SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY. THURSDAY INTO
THURSDAY NIGHT A STRONGER FRONTAL SYSTEM IS LIKELY TO CAUSE GALE
FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. FORERUNNERS OF VERY
LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY
MORNING. THIS VERY LARGE WEST SWELL WILL BUILD FRIDAY, LIKELY
PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
  PZZ350-356-370-376.
- HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
  THURSDAY NIGHT FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON
  FOR PZZ376.

$$

TRW/BTL



000
FXUS66 KMFR 171340
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
540 AM PST WED DEC 17 2014

.DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/12Z TAF CYCLE...
WEAK LOW PRESSURE WILL CONTINUE A GENERAL SOUTH TO SOUTHWEST FLOW
ACROSS THE AREA TODAY, WITH SHOWERS THROUGH THE DAY. THESE SHOWERS
WILL BE MOST NUMEROUS IN THE MOUNT SHASTA AREA, WESTERN SISKIYOU
COUNTY, AND ALONG AND NEAR THE COAST TODAY. FOR INLAND AREAS THE
BEST CHANCE OF PRECIPITATION WILL BE THIS AFTERNOON AND EVENING.
PRECIPITATION WILL BE MOSTLY RAIN BELOW 4KFT ELEVATIONS AND SNOW
ABOVE 5KFT, WITH A MIX FOR ELEVATIONS IN BETWEEN. MOSTLY VFR
CONDITIONS EXIST THIS MORNING, THOUGH AREAS OF LIFR FOG HAVE FORMED
IN THE UMPQUA BASIN. EXPECT THAT THIS LIFR WILL IMPROVE TO ONLY IFR
TO MVFR IN THE UMPQUA BASIN THIS AFTERNOON, WITH CONDITIONS LOWERING
TO MVFR FOR MOST INLAND LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT
TERRAIN OBSCURATIONS TO BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE
INTERIOR WEST SIDE THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF
THIS EVENING. IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM
ACROSS THE VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL

&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...
WEAKENING SURFACE LOW PRESSURE MOVING NORTHEASTWARD ACROSS THE
COASTAL WATERS THIS MORNING WILL BE FOLLOWED BY ANOTHER LOW
PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS WILL RESULT IN A
SURGE OF WEST WINDS THIS MORNING INTO EARLY AFTERNOON. SOUTHWEST
SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY. THURSDAY INTO
THURSDAY NIGHT A STRONGER FRONTAL SYSTEM IS LIKELY TO CAUSE GALE
FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. FORERUNNERS OF VERY
LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY
MORNING. THIS VERY LARGE WEST SWELL WILL BUILD FRIDAY, LIKELY
PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
  PZZ350-356-370-376.
- HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
  THURSDAY NIGHT FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON
  FOR PZZ376.

$$

TRW/BTL



000
FXUS66 KMFR 171340
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
540 AM PST WED DEC 17 2014

.DISCUSSION...
A WEAKENING UPPER TROUGH IS MOVING INLAND THIS MORNING, AND WE
CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH OF SISKIYOU
COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT AND LIKELY
OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE ONLY SEEN A
MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY. PRECIPITATION
AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH OF LIQUID IN
THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT JUST WASN`T
QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE HARD ENOUGH TO
DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED, IT IS SNOWING
JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF MOISTURE MOVING
IN, SO WE`LL LET THE WINTER WEATHER ADVISORY CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/12Z TAF CYCLE...
WEAK LOW PRESSURE WILL CONTINUE A GENERAL SOUTH TO SOUTHWEST FLOW
ACROSS THE AREA TODAY, WITH SHOWERS THROUGH THE DAY. THESE SHOWERS
WILL BE MOST NUMEROUS IN THE MOUNT SHASTA AREA, WESTERN SISKIYOU
COUNTY, AND ALONG AND NEAR THE COAST TODAY. FOR INLAND AREAS THE
BEST CHANCE OF PRECIPITATION WILL BE THIS AFTERNOON AND EVENING.
PRECIPITATION WILL BE MOSTLY RAIN BELOW 4KFT ELEVATIONS AND SNOW
ABOVE 5KFT, WITH A MIX FOR ELEVATIONS IN BETWEEN. MOSTLY VFR
CONDITIONS EXIST THIS MORNING, THOUGH AREAS OF LIFR FOG HAVE FORMED
IN THE UMPQUA BASIN. EXPECT THAT THIS LIFR WILL IMPROVE TO ONLY IFR
TO MVFR IN THE UMPQUA BASIN THIS AFTERNOON, WITH CONDITIONS LOWERING
TO MVFR FOR MOST INLAND LOCATIONS AS SHOWERS MOVE THROUGH. EXPECT
TERRAIN OBSCURATIONS TO BE MOSTLY PARTIAL, BUT NEARLY TOTAL FOR THE
INTERIOR WEST SIDE THIS AFTERNOON. SHOWERS ARE EXPECTED TO TAPER OFF
THIS EVENING. IFR TO LIFR FOG AND LOW CLOUDS ARE EXPECT TO FORM
ACROSS THE VALLEYS LATE TONIGHT THROUGH THURSDAY MORNING. BTL

&&

.MARINE...UPDATED 300 AM PST WED DEC 17 2014...
WEAKENING SURFACE LOW PRESSURE MOVING NORTHEASTWARD ACROSS THE
COASTAL WATERS THIS MORNING WILL BE FOLLOWED BY ANOTHER LOW
PRESSURE SYSTEM APPROACHING FROM THE WEST. THIS WILL RESULT IN A
SURGE OF WEST WINDS THIS MORNING INTO EARLY AFTERNOON. SOUTHWEST
SEAS WILL REMAIN MOSTLY AT OR ABOVE 10 FEET TODAY. THURSDAY INTO
THURSDAY NIGHT A STRONGER FRONTAL SYSTEM IS LIKELY TO CAUSE GALE
FORCE WINDS AND VERY STEEP SOUTHWEST SEAS. FORERUNNERS OF VERY
LARGE WEST SWELL WILL BEGIN TO ARRIVE IN THE PREDAWN HOURS FRIDAY
MORNING. THIS VERY LARGE WEST SWELL WILL BUILD FRIDAY, LIKELY
PEAKING FRIDAY NIGHT AROUND 20 FEET AT 19 SECONDS. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
  PZZ350-356-370-376.
- HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
  THURSDAY NIGHT FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350-356-370-376.
- SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON
  FOR PZZ376.

$$

TRW/BTL



000
FXUS66 KPDT 171153 AAB
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171153 AAB
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171153 AAB
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171153 AAB
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
355 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. LOCALLY DENSE FOG AND FREEZING FOG AS WELL.
EXPECT THIS TO CONTINUE INTO THE MORNING THEN DISSIPATE BY
AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE THROUGH
OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW CLOUDS
AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE WILL
BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS OVER
THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ507-508.

     DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING WAZ029.

     AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171131 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
332 AM PST WED DEC 17 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. EXPECT THIS TO CONTINUE INTO THE MORNING THEN
DISSIPATE BY AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE
THROUGH OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW
CLOUDS AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE
WILL BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS
OVER THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 171131 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
332 AM PST WED DEC 17 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. EXPECT THIS TO CONTINUE INTO THE MORNING THEN
DISSIPATE BY AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE
THROUGH OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW
CLOUDS AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE
WILL BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS
OVER THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...12Z TAFS...LOW STRATUS AND FOG/FZFG/BR WILL CONTINUE
OVER THE NEXT 24 HOURS AT ALL TAF SITES. IFR/LIFR CONDITIONS WILL
CONTINUE AT ALL SITES...EXCEPT KYKM...THRU 17/18Z BEFORE THE STRATUS
DECK LIFTS WITH PRECIPITATION STARTING.  CIG/VIS WILL IMPROVE TO
MVFR/IFR BTWN 17/18Z THRU 18/03Z DUE TO POTENTIAL FOR RAIN AT
KDLS...KPDT...KALW...KPSC...AND KYKM WITH SNOW AT KRDM AND KBDN.
AFT 18/03Z...THE LOW STRATUS AND FOG BANK WILL REESTABLISH ITSELF
AND ONCE AGAIN RETURN CONDITIONS AT NEARLY ALL TAF SITES TO
LIFR/IFR.  WINDS WILL BE AOB 10 KTS DURING THE PERIOD.  AVIATION
DISCUSSIONS ARE NOT UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98






000
FXUS66 KMFR 171110
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
310 AM PST WED DEC 17 2014

.DISCUSSION...A WEAKENING UPPER TROUGH IS MOVING INLAND THIS
MORNING, AND WE CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH
OF SISKIYOU COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT
AND LIKELY OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE
ONLY SEEN A MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY.
PRECIPITATION AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH
OF LIQUID IN THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT
JUST WASN`T QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE
HARD ENOUGH TO DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED,
IT IS SNOWING JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF
MOISTURE MOVING IN, SO WE`LL LET THE WINTER WEATHER ADVISORY
CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/06Z TAF CYCLE...ISOLATED IFR CIGS/VSBYS
IN LOW CLOUDS AND FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE
TONIGHT THROUGH MID-MORNING...MAINLY IN THE UMPQUA BASIN. CONDITIONS
FROM THE CASCADES WESTWARD INTO THIS AFTERNOON WILL BE MAINLY MVFR
AND LOCAL IFR WITH MOUNTAIN OBSCURATION AND PERIODS OF RAIN AND
SNOW. EAST OF THE CASCADES...PRECIPITATION WILL BE LESS FREQUENT
WITH A MIX OF MVFR AND VFR CEILINGS. PRECIPITATION ACROSS THE AREA
WILL GRADUALLY TAPER OFF FROM THE AFTERNOON THROUGH THE EVENING WITH
VALLEY LOW CLOUDS AND FOG LIKELY TO FORM OVERNIGHT INTO THURSDAY
MORNING.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE OVER THE
WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH WINDS AND
BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND BEYOND 10NM
OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY THEN RETURN TO
SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL PUSH THROUGH ON
THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING GALE STRENGTH.
VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT PERIOD OF 19
SECONDS WILL ARRIVE ON FRIDAY AND LIKELY REMAIN VERY HIGH INTO
SATURDAY.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH
      THURSDAY EVENING FOR PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON FOR
     PZZ376.

$$



000
FXUS66 KMFR 171110
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
310 AM PST WED DEC 17 2014

.DISCUSSION...A WEAKENING UPPER TROUGH IS MOVING INLAND THIS
MORNING, AND WE CONTINUE TO SEE UPSLOPE RAIN AND SNOW OVER MUCH
OF SISKIYOU COUNTY. IT IS NOW SNOWING MODERATELY AT SNOWMAN SUMMIT
AND LIKELY OTHER ELEVATIONS ABOVE AROUND 4000 FT. SO FAR, WE`VE
ONLY SEEN A MIX DOWN TO THE INTERSTATE LEVEL AT MT. SHASTA CITY.
PRECIPITATION AMOUNTS HAVE BEEN FAIRLY HEFTY WITH AROUND 3/4 INCH
OF LIQUID IN THE AREA OVER THE LAST 12 HOURS, SO IT APPEARS IT
JUST WASN`T QUITE COLD ENOUGH AND PRECIP DIDN`T COME DOWN QUITE
HARD ENOUGH TO DRIVE SNOW LEVELS ALL THE WAY DOWN. AS MENTIONED,
IT IS SNOWING JUST ABOVE TOWN, AND THERE ARE ADDITIONAL BANDS OF
MOISTURE MOVING IN, SO WE`LL LET THE WINTER WEATHER ADVISORY
CONTINUE.

ELSEWHERE, PRECIPITATION IS RATHER SPARSE. WE`LL LIKELY SEE AN
UPTICK IN AREAL COVERAGE LATER THIS MORNING, ESPECIALLY OVER THE
MOUNTAINS, AS THE TROUGH AXIS MOVES FURTHER INLAND. WE HAVE HAD
GUSTY SOUTHEAST WINDS ALL NIGHT OVER THE SHASTA AND ROGUE VALLEYS.
IT IS UNUSUAL, BUT THE ROGUE VALLEY HAS BEEN OUR WINDIEST VALLEY
LOCATION THIS MORNING WITH GUSTS AT THE MEDFORD AIRPORT REACHING
AS HIGH AS 35 MPH. WINDS ARE ALREADY DECREASING AND WILL CONTINUE
TO DO SO AS THE TROUGH AND ASSOCIATED SURFACE LOW PRESSURE MOVE
INLAND AND GRADIENTS RELAX.

WE WILL SEE A BRIEF BREAK IN PRECIPITATION THURSDAY AS AN UPPER
RIDGE MOVES THROUGH. IT WILL BE A QUICK TRANSIT, THOUGH, AS THE
NEXT FRONT WILL ALREADY HAVE RAIN SPREADING INTO THE WATERS BY
DAY`S END. THE FRONT IS FASTER THAN IT LOOKED YESTERDAY, AND WILL
BLOW THROUGH OUR AREA BY EARLY FRIDAY AFTERNOON. IT IS A FAIRLY
WET SYSTEM, BUT IT`S MOVING SO QUICKLY WE WON`T SEE EXCESSIVE RAIN
WITH IT.

THE MODELS NOW ALL SHOW A MUCH FLATTER RIDGE OVER THE WEEKEND THAN
THEY HAD BEEN, SO FLAT IN FACT, THAT IT WON`T BE MUCH RESISTANCE
TO INCOMING PRECIPITATION UNTIL IT BEGINS TO AMPLIFY EARLY NEXT
WEEK. MODELS SHOW A STRONG NEARLY ZONAL JET AND A JUICY MOISTURE
PLUME TAKING AIM AT THE PACNW. GIVEN THE GENERAL WESTERLY FLOW,
PRECIPITATION WILL BE MOST PREVALENT WEST OF THE CASCADES, BUT I
HAVE RAISED POPS ACROSS THE BOARD OVER THE WEEKEND. EARLY NEXT
WEEK A TROUGH FORMS OUT AROUND 160W WHICH INDUCES RIDGING OVER THE
WEST COAST, AND AT THIS POINT THE MOISTURE PLUME SHIFTS NORTH OF
US. THUS, I LOWERED POPS EARLY NEXT WEEK. -WRIGHT

&&

.AVIATION...BASED ON THE 17/06Z TAF CYCLE...ISOLATED IFR CIGS/VSBYS
IN LOW CLOUDS AND FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE
TONIGHT THROUGH MID-MORNING...MAINLY IN THE UMPQUA BASIN. CONDITIONS
FROM THE CASCADES WESTWARD INTO THIS AFTERNOON WILL BE MAINLY MVFR
AND LOCAL IFR WITH MOUNTAIN OBSCURATION AND PERIODS OF RAIN AND
SNOW. EAST OF THE CASCADES...PRECIPITATION WILL BE LESS FREQUENT
WITH A MIX OF MVFR AND VFR CEILINGS. PRECIPITATION ACROSS THE AREA
WILL GRADUALLY TAPER OFF FROM THE AFTERNOON THROUGH THE EVENING WITH
VALLEY LOW CLOUDS AND FOG LIKELY TO FORM OVERNIGHT INTO THURSDAY
MORNING.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE OVER THE
WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH WINDS AND
BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND BEYOND 10NM
OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY THEN RETURN TO
SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL PUSH THROUGH ON
THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING GALE STRENGTH.
VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT PERIOD OF 19
SECONDS WILL ARRIVE ON FRIDAY AND LIKELY REMAIN VERY HIGH INTO
SATURDAY.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST THIS MORNING FOR
     CAZ082-083.

PACIFIC COASTAL WATERS...GALE WATCH FROM THURSDAY MORNING THROUGH
      THURSDAY EVENING FOR PZZ350-356-370-376.
     HAZARDOUS SEAS WATCH FROM THURSDAY AFTERNOON THROUGH LATE
     THURSDAY NIGHT FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
     AFTERNOON FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 PM PST THIS AFTERNOON FOR
     PZZ376.

$$




000
FXUS66 KPQR 171059
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
259 AM PST WED DEC 17 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND EVENTUALLY MOVE ONSHORE ALONG THE N OR/S WA COAST
THIS AFTERNOON. THIS WILL MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY
OVER THE HIGHER TERRAIN THIS MORNING. AN UPPER LEVEL SHORTWAVE WILL
PUSH ONSHORE LATER TODAY...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH SATURDAY...VERY LIGHT RAIN CONTINUES TO
IMPACT SW WASHINGTON THIS MORNING BUT HAS OTHERWISE STARTED TO
DISSIPATE OVER THE SOUTHERN PORTION OF THE FORECAST AREA. WATER VAPOR
IMAGERY SHOWS A CLOSED LOW WEAKENING AS IT HAS PUSHED ONSHORE NEAR
THE OREGON/CALIFORNIA BORDER...WHILE AN UPPER LEVEL SHORTWAVE IS
ELONGATING AS IT APPROACHES THE PACIFIC NORTHWEST COASTLINE. NOT MUCH
CHANGE IN THE KTTD-KDLS GRADIENT...WHICH REMAINS AROUND -5 EARLY THIS
MORNING. EAST WINDS CONTINUE TO GUST NEAR 25 MPH THROUGH THE
GORGE...BUT EXPECT THE EASTERLY GRADIENT TO WEAKEN BY LATE TONIGHT.

AFTER A PERIOD OF LIGHT RAIN THIS MORNING...MODELS REMAIN CONSISTENT
IN SHOWING AN UPTICK IN PRECIP BY THIS AFTERNOON ASSOCIATED WITH THE
VORT MAX JUST OFFSHORE AROUND 45N 134W. THE LOWER LEVEL MOISTURE
ASSOCIATED WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING
FROM THE SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP THIS
EVENING AND THROUGH TONIGHT. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY.

WITH CLEARING SKIES AND LIGHT WINDS...SHOULD SEE SOME SHALLOW FOG TO
DEVELOP IN INTERIOR VALLEYS TONIGHT THROUGH EARLY THU MORNING. MODELS
MAINTAIN A THREAT FOR LIGHT PRECIP OVER THE HIGHER TERRAIN MUCH OF
THU...BUT OTHERWISE EXPECT DRY CONDITIONS TO PERSIST TO LOWER
ELEVATIONS. THE NEXT SIGNIFICANT FRONTAL SYSTEM ARRIVES LATE
THU...SPREADING RAIN AND BRINGING GUSTY COASTAL WINDS TO THE REGION
THROUGH FRI. PRECIPITABLE WATER IS EXPECTED TO BE NEAR AN INCH AND AN
APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND EXPECT THE
HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE COAST AND COAST
RANGE THROUGH MIDDAY FRI. OTHER LOCATIONS WILL SEE ON AVERAGE 0.5
INCHES OF RAIN. SNOW LEVELS SHOULD REMAIN ABOVE 5000 FEET DURING THE
PEAK RAIN PERIOD...BUT LOWER TO NEAR OR BELOW THE CASCADE PASSES
BEHIND THE FRONT FRIDAY AFTERNOON.

STRONG LOW PRESSURE OVER THE GULF OF ALASKA WILL PUSH INLAND LATE FRI
INTO EARLY SAT MORNING...SIMULTANEOUSLY FLATTENING A BROAD AREA OF
HIGH PRESSURE OVER THE EASTERN PACIFIC. THERE IS INCREASING
CONFIDENCE AN ATMOSPHERIC RIVER SCENARIO WILL SET UP...WITH ABUNDANT
MOISTURE AIMED DIRECTLY AT THE PACIFIC NORTHWEST SAT.

.LONG TERM...SATURDAY NIGHT THROUGH TUESDAY...AS THIS TROUGH MOVES ON
SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES ONSHORE AND STALLS
EAST-TO-WEST ACROSS NORTHWEST OREGON AND SOUTHWEST WASHINGTON. THIS
PUTS OUR AREA IN THE PATH OF RAIN STARTING SATURDAY THROUGH MONDAY.
SOME UNCERTAINTY EXISTS IN WHERE THIS BOUNDARY WILL SET UP...WHICH
WILL DETERMINE HOW MUCH RAINFALL WE WILL GET. ON TUESDAY...GEFS
ENSEMBLE SPAGHETTI PLOTS GET MESSY AND SIGNIFICANT DIFFERENCES START
TO SHOW UP BETWEEN THE GFS AND ECMWF...DECREASING CONFIDENCE ON HOW
THE REST OF THE WEEK WILL SHAPE UP.  AS OF NOW...THE MOST COMMON
SOLUTION IS THAT HIGH PRESSURE RIDGING WILL START TO BUILD BACK OVER
THE WESTERN U.S. WHICH SUGGESTS DRIER WEATHER STARTING TUESDAY...
THOUGH UNCERTAINTY IS VERY HIGH. -MCCOY

&&

.AVIATION...VFR CONDITIONS TO PERSIST AT MOST TAF SITES THROUGH
WEDNESDAY AFTERNOON. THE QUESTION STILL REMAINS WHETHER LOW LEVEL
STRATUS/FOG WILL DEVELOP IN THE CENTRAL AND SOUTH WILLAMETTE
VALLEY. IF LOW LEVEL STRATUS/FOG DOES DEVELOP EXPECT IT TO CLEAR
OUT BY EARLY WEDNESDAY AFTERNOON. BRIEF PERIODS OF MVFR TO IFR
CIGS AND VIS ARE POSSIBLE UNDER LIGHT TO MODERATE RAIN BANDS
THROUGH LATE WEDNESDAY. WITH CLEARING EXPECTED LATE WEDNESDAY WE
WILL LIKELY SEE THE DEVELOPMENT OF IFR CIGS AND VIS DUE TO LOW
LEVEL STRATUS/FOG RETURNING TO PORTIONS OF THE VALLEY.

KPDX AND APPROACHES...VFR CONDITIONS TO PERSIST WEDNESDAY.
HOWEVER...BRIEF PERIODS OF MVFR CIGS AND VIS ARE POSSIBLE UNDER
LIGHT TO MODERATE RAIN BANDS THROUGH WEDNESDAY AFTERNOON. /64

&&

.MARINE...RATHER BENIGN CONDITIONS TO CONTINUE THROUGH EARLY
THURSDAY AS A WEAK LOW PRESSURE SYSTEM MOVES INLAND OVER NORTHERN
CALIFORNIA. EXPECT SEAS TO REMAIN BELOW 10 FT WITH GUST TO 20 KT
POSSIBLE. ANOTHER LOW PRESSURE SYSTEM CONTINUES TO STRENGTHEN
OFFSHORE AND LOOKS TO MOVE ACROSS THE COASTAL WATERS ON THURSDAY.
THIS SYSTEM WILL LIKELY BRING SOUTHERLY GALES THURSDAY THROUGH
EARLY FRIDAY...BUT THERE IS STILL SOME UNCERTAINTY ON THE EXACT
TIMING. SEAS WITH THIS SYSTEM ARE EXPECTED TO BUILD INTO THE UPPER
TEENS TO THE LOW 20S BY SATURDAY MORNING. AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH NEXT WEEK AND COULD BRING MORE
SOUTHERLY GALES AND ELEVATED SEAS. /64

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

WA...NONE.

PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT
     60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 AM
    THIS MORNING TO 4 PM PST THIS AFTERNOON.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPDT 171050
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
244 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. EXPECT THIS TO CONTINUE INTO THE MORNING THEN
DISSIPATE BY AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE
THROUGH OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW
CLOUDS AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE
WILL BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS
OVER THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LOW STRATUS AND
FZFG/FOG/BR WILL PERSIST NEAR TAF SITES FOR THE NEXT 24 HOURS. KRDM
AND KBDN WILL BE AT IFR/LIFR LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN
AROUND 13-15Z WHEN CEILINGS WILL LIFT TO MVFR. SHOWERS WILL SWITCH
TO RAIN AFTER 18Z. KDLS WILL BE BELOW MINS (CIG LESS THAN 012) UNTIL
15Z. KPDT AND KALW WILL  HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN
SHOWERS WILL DEVELOP AND IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND
KYKM WILL REMAIN HAVE CIG AROUND 010-015 UNTIL 15-17Z WHEN RAIN
SHOWERS WILL HELP IMPROVE CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN
BELOW 10 KTS FOR THE NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98








000
FXUS66 KPDT 171050
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
244 AM PST WED DEC 17 2014

.SHORT TERM...TODAY THROUGH FRIDAY. WEAK UPPER LEVEL TROUGH MOVING
ACROSS THE FORECAST AREA TODAY WITH SOME LIGHT RAIN AND MOUNTAIN
SNOW. CURRENT SURFACE OBSERVATIONS SHOWING PLENTY OF LOW CLOUDS AND
FOG OVER THE REGION. EXPECT THIS TO CONTINUE INTO THE MORNING THEN
DISSIPATE BY AFTERNOON. ANOTHER SYSTEM JUST OFF THE COAST WILL MOVE
THROUGH OVERNIGHT WITH ADDITIONAL LIGHT RAIN AND MOUNTAIN SNOW. LOW
CLOUDS AND FOG WILL LIKELY REDEVELOP OVERNIGHT. AN UPPER LEVEL RIDGE
WILL BE OVER THE AREA THURSDAY. A FEW LINGERING LIGHT SNOW SHOWERS
OVER THE MOUNTAINS OTHERWISE MOSTLY CLOUDY WITH AREAS OF FOG IN THE
MORNING. A STRONGER UPPER LEVEL TROUGH WILL PUSH A COLD FRONT
THROUGH THE REGION LATE THURSDAY NIGHT INTO FRIDAY MORNING. THIS
WILL BRING A PERIOD OF RAIN AND MOUNTAIN SNOW. WINDS WILL INCREASE
WITH THE FRONTAL PASSAGE. WINDS REMAIN LIGHT TODAY AND THURSDAY
EXCEPT FOR SOME SOUTH WIND THROUGH THE GRANDE RONDE VALLEY. THE
FRONTAL PASSAGE ON FRIDAY WILL CAUSE AN INCREASE IN WINDS. 94

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY NIGHT...LATEST MODEL
GUIDANCE CONTINUES TO SHOW AN ACTIVE WEATHER PATTERN DURING THE
FORECAST PERIOD.  A SHORTWAVE TROUGH WILL BE EXITING THE AREA FRIDAY
NIGHT THRU EARLY SATURDAY WILL BRING A CHANCE OF RAIN-SNOW MIX TO
THE HIGHER ELEVATIONS OF THE CWA.  THE MAJOR HIGHLIGHT TO THE LONG
TERM IS A CHANGE IN THE LONGWAVE PATTERN THAT WILL BRING AN
IMPRESSIVE 150 KT JET WITH A POTENTIAL ATMOSPHERIC RIVER INTO THE
WASHINGTON STATE/OREGON AREA SATURDAY THRU MONDAY.  PRECIPITATION
CHANCES INCREASE INTO AT LEAST THE CHANCE CATEGORY SATURDAY NIGHT
THROUGH MIDDAY MONDAY AS MODEL GUIDANCE AND ENSEMBLE CONFIDENCE.
MOISTURE ADVECTION INTO THE REGION DURING THE PERIOD IS ABOUT 2 TO 3
STANDARD DEVIATIONS ABOVE NORMAL.  THE ORIGINS OF THE PACIFIC
AIRMASS...THOUGH...WILL ALLOW SNOW LEVELS TO GRADUALLY RISE AS THE
LONGWAVE TROUGH MOVES ACROSS THE REGION WITH ACCUMULATIONS ONLY
EXPECTED AT THE HIGHER ELEVATIONS OF THE CWA.  THE WEST-EAST JET
STREAM OVER THE REGION WILL HAVE VIGOROUS LOW-LEVEL JET SUPPORT
RANGING FROM 50-70 KTS FAVORING THE WASHINGTON STATE/OREGON BORDER.
HAVE ASSESSED CROSS-SECTIONS OVER THE FAVORED WIND PRONE REGIONS AND
FEEL THAT A MOUNTAIN WAVE MAY BE POSSIBLE OVER THE SIMCOE HIGHLANDS
AND THE IMMEDIATE EAST SLOPES OF THE CASCADES.  HAVE INCREASED WINDS
TO BETWEEN 30-50 KTS IN THOSE AREAS GIVEN THIS POTENTIAL SCENARIO
SUNDAY AND MONDAY.  BREEZY TO WINDY CONDITIONS MAY ALSO OCCUR ALONG
OTHER AREAS...THOUGH NOT TO THE MAGNITUDE EXPECTED IN THE AREAS
MENTIONED EARLIER. A LONG WAVE RIDGE WILL START TO BUILD IN BEHIND
THE TROUGH LATE MONDAY THRU TUESDAY THAT SHOULD ALLOW FOR
PRECIPITATION CHANCES TO DECREASE...THOUGH SOME SPILL OVER MOISTURE
ATOP THE RIDGE MAY ALLOW FOR A CHANCE OF PRECIPITATION FAVORING THE
EAST SLOPES OF THE WASHINGTON CASCADES.  TEMPERATURES DURING THE
EXTENDED PERIOD WILL BE 10 TO 15 DEGREES ABOVE NORMAL WITH A HIGHLY
ANOMALOUS PRECIPITATION EVENT POSSIBLE.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LOW STRATUS AND
FZFG/FOG/BR WILL PERSIST NEAR TAF SITES FOR THE NEXT 24 HOURS. KRDM
AND KBDN WILL BE AT IFR/LIFR LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN
AROUND 13-15Z WHEN CEILINGS WILL LIFT TO MVFR. SHOWERS WILL SWITCH
TO RAIN AFTER 18Z. KDLS WILL BE BELOW MINS (CIG LESS THAN 012) UNTIL
15Z. KPDT AND KALW WILL  HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN
SHOWERS WILL DEVELOP AND IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND
KYKM WILL REMAIN HAVE CIG AROUND 010-015 UNTIL 15-17Z WHEN RAIN
SHOWERS WILL HELP IMPROVE CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN
BELOW 10 KTS FOR THE NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  39  33  42  36 /  20  30  10  30
ALW  40  34  42  37 /  20  30  10  30
PSC  40  32  40  35 /  20  30  10  40
YKM  38  30  38  33 /  30  30  10  60
HRI  40  33  41  35 /  20  30  10  40
ELN  37  29  37  32 /  30  30  10  60
RDM  40  27  42  32 /  30  30  10  50
LGD  39  32  40  34 /  20  40  20  30
GCD  40  32  40  32 /  30  30  20  30
DLS  42  35  41  38 /  40  40  10  70

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST THIS MORNING ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98









000
FXUS65 KBOI 170943
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
242 AM MST WED DEC 17 2014

.SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO-DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.AVIATION...SCATTERED MID LEVEL CLOUDS OVER SOUTHWEST IDAHO WITH
SCATTERED TO BROKEN MID LEVEL CLOUDS OVER SOUTHEAST OREGON.  LOCAL
IFR STRATUS AND FOG AT KBNO...KBKE AND KMYL UNTIL 18Z.  SURFACE
WINDS WILL BE 10 KNOTS OR LESS.  WINDS ALOFT WILL BE SOUTH TO
SOUTHWEST 10-15 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 170942
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
242 AM MST WED DEC 17 2014

.SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.AVIATION...SCATTERED MID LEVEL CLOUDS OVER SOUTHWEST IDAHO WITH
SCATTERED TO BROKEN MID LEVEL CLOUDS OVER SOUTHEAST OREGON.  LOCAL
IFR STRATUS AND FOG AT KBNO...KBKE AND KMYL UNTIL 18Z.  SURFACE
WINDS WILL BE 10 KNOTS OR LESS.  WINDS ALOFT WILL BE SOUTH TO
SOUTHWEST 10-15 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 170942
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
242 AM MST WED DEC 17 2014

.SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.AVIATION...SCATTERED MID LEVEL CLOUDS OVER SOUTHWEST IDAHO WITH
SCATTERED TO BROKEN MID LEVEL CLOUDS OVER SOUTHEAST OREGON.  LOCAL
IFR STRATUS AND FOG AT KBNO...KBKE AND KMYL UNTIL 18Z.  SURFACE
WINDS WILL BE 10 KNOTS OR LESS.  WINDS ALOFT WILL BE SOUTH TO
SOUTHWEST 10-15 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 170942
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
242 AM MST WED DEC 17 2014

.SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.AVIATION...SCATTERED MID LEVEL CLOUDS OVER SOUTHWEST IDAHO WITH
SCATTERED TO BROKEN MID LEVEL CLOUDS OVER SOUTHEAST OREGON.  LOCAL
IFR STRATUS AND FOG AT KBNO...KBKE AND KMYL UNTIL 18Z.  SURFACE
WINDS WILL BE 10 KNOTS OR LESS.  WINDS ALOFT WILL BE SOUTH TO
SOUTHWEST 10-15 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 170942
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
242 AM MST WED DEC 17 2014

.SHORT TERM...AT 09Z STRATUS SEEN ON SATELLITE IMAGERY COVERED NRN
MALHEUR COUNTY AND WRN BAKER COUNTY IN OREGON AS WELL AS VALLEYS IN
BOISE COUNTY AND VALLEY COUNTY IN IDAHO.  STRATUS SHOULD PERSIST
THROUGH THIS MORNING.  I/R SATELLITE IMAGERY ALSO SHOWED AN UPPER
TROUGH ALONG THE SRN OREGON/NRN CALIFORNIA COAST.  MODELS MOVE THE
TROUGH INLAND AND WEAKEN IT TODAY THROUGH THURSDAY.  ONLY LIGHT PCPN
EXPECTED IN OUR CWA MAINLY TONIGHT AND THURSDAY AND MOSTLY IN NRN
ZONES.  LITTLE DAY-TO DAY TEMPERATURE CHANGE THROUGH THURSDAY.
LIGHT SOUTHEAST WINDS IN OPEN AREAS...LIGHT AND VARIABLE ELSEWHERE.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODELS REMAIN IN
RELATIVELY GOOD AGREEMENT...BUT THERE STILL ARE SOME MINOR
DIFFERENCES FROM MODEL RUN TO MODEL RUN IN PLACEMENT AND TIMING OF
SYSTEMS AS THEY MOVE THROUGH THE FLOW.  FLOW REMAINS PROGRESSIVE
THROUGH THE EXTENDED.  THURSDAY NIGHT UPPER LEVEL RIDGE WILL MOVE
OVER THE REGION WITH THE NEXT UPPER LEVEL TROUGH MOVING INTO THE
WEST COAST ON FRIDAY WITH PRECIPITATION SPREADING INTO SOUTHEAST
OREGON LATE THURSDAY NIGHT AND OVER SOUTHWEST IDAHO ON FRIDAY.
TEMPERATURES WILL AVERAGE 5 DEGREES ABOVE NORMAL FOR VALLEY RAIN AND
MOUNTAIN SNOW.  PRECIPITATION DECREASES OVER THE REGION FRIDAY NIGHT
AS THE UPPER LEVEL TROUGH MOVES QUICKLY EAST BUT ENOUGH MOISTURE
WILL REMAIN IN THE FLOW FOR AT LEAST CHANCE POPS OVER THE ENTIRE
FORECAST AREA THROUGH SATURDAY NIGHT.  FLAT RIDGE BUILDS OVER THE
REGION SUNDAY NIGHT AND REMAINS OVER THE REGION THROUGH TUESDAY...
BUT ENOUGH MOISTURE WILL MOVE OVER THE CREST OF THE RIDGE FOR
CHANCE TO LIKELY POPS OVER NORTHERN ZONES WITH SLIGHT CHANCE OVER
SOUTHERN ZONES.  TEMPERATURES INTO THE WEEKEND AND EARLY NEXT WILL
WILL REMAIN MILD WITH HIGH TEMPERATURES AVERAGING 5-7 DEGREES ABOVE
NORMAL.

&&

.AVIATION...SCATTERED MID LEVEL CLOUDS OVER SOUTHWEST IDAHO WITH
SCATTERED TO BROKEN MID LEVEL CLOUDS OVER SOUTHEAST OREGON.  LOCAL
IFR STRATUS AND FOG AT KBNO...KBKE AND KMYL UNTIL 18Z.  SURFACE
WINDS WILL BE 10 KNOTS OR LESS.  WINDS ALOFT WILL BE SOUTH TO
SOUTHWEST 10-15 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS66 KMFR 170530
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
930 PM PST TUE DEC 16 2014

.DISCUSSION...LOW PRESSURE OVER THE COASTAL WATERS WILL MOVE EAST
TO NORTHEAST TONIGHT WITH COLD FRONTAL PRECIPITATION FOCUSED FROM
THE MT SHASTA AREA SOUTHWARD. IT IS PRESENTLY 38 DEGREES AND
RAINING AT MT SHASTA CITY. PRECIPITATION ALONG THE I-5 CORRIDOR
IN FAR SOUTH CENTRAL SISKIYOU COUNTY WILL LIKELY CHANGE OVER TO
SNOW LATE TONIGHT...SHORTLY AFTER 2 AM...WITH THE SNOW LEVEL
IN THAT LOCAL AREA DROPPING TO AROUND 3000 FEET WITH MORE INTENSE
PRECIPITATION RATES LOWERING THE SNOW LEVEL. SNOWFALL AMOUNTS
TONIGHT ARE FORECAST TO BE AROUND 1 TO 3 INCHES NEAR MT SHASTA.
MEANTIME, THERE IS A CHANCE OF LIGHT SNOW OVER THE SOUTHERN
OREGON CASCADES AND EAST SIDE WITH NOT MUCH MORE THAN A DUSTING AT
ELEVATIONS ABOVE 4500 FEET.

A MORE WIDESPREAD SHOWERY PATTERN WILL DEVELOP FOR OUR AREA ON
WEDNESDAY...ESPECIALLY ON THE WEST SIDE. THE SNOW LEVEL WILL
REMAIN AROUND 4500 FEET WITH 1 TO 3 INCHES OF SNOW POSSIBLE FOR
THE SOUTHERN OREGON SISKIYOU AND CASCADE MOUNTAINS. SHOWERS AND
SNOW SHOWERS WILL DIMINISH WEDNESDAY NIGHT AS A RIDGE BUILDS TO
THE COAST.

A FOCUS FOR THE NIGHT SHIFT WILL BE ON THE DETAILS OF WHAT LOOK TO
BE STRONGER FRONTS TO AFFECT OUR AREA THURSDAY EVENING INTO
FRIDAY AFTERNOON AND THEN SATURDAY INTO EARLY SUNDAY. THIS SECOND
SYSTEM ON THE WEEKEND HAS HIGHER UNCERTAINTY/MODEL SOLUTION
VARIABILITY.

&&

.AVIATION...BASED ON THE 17/00Z TAF CYCLE...CONDITIONS REMAIN VFR
ACROSS THE MEDFORD CWA THIS EVENING WITH THE NOTABLE EXCEPTION OF
MVFR CEILINGS OVER SOUTHERN SISKIYOU COUNTY WITH MOUNTAIN
OBSCURATION AND LIGHT TO MODERATE RAIN AND SNOW. ALSO...STRONG
SOUTHERLY LOW LEVEL WINDS WILL DIMINISH AFTER MIDNIGHT.
OVERNIGHT...AREAS OF MVFR CIGS IN PRECIPITATION WILL INCREASE
ALONG THE SOUTH COAST RANGE AND OVER MOST OF SISKIYOU COUNTY WITH
HIGHER TERRAIN OBSCURED. ISOLATED IFR CIGS/VSBYS IN LOW CLOUDS AND
FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE TONIGHT THROUGH
MID-MORNING WEDNESDAY...MAINLY IN THE UMPQUA BASIN.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE
OVER THE WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH
WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND
BEYOND 10NM OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY
THEN RETURN TO SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL
PUSH THROUGH ON THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING
GALE STRENGTH. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A
DOMINANT PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY AND LIKELY
REMAIN VERY HIGH INTO SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 216 PM PST TUE DEC 16 2014/

DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST WEDNESDAY FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST
     WEDNESDAY FOR PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
     WEDNESDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.

$$

DW/DW/SBN



000
FXUS66 KMFR 170530
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
930 PM PST TUE DEC 16 2014

.DISCUSSION...LOW PRESSURE OVER THE COASTAL WATERS WILL MOVE EAST
TO NORTHEAST TONIGHT WITH COLD FRONTAL PRECIPITATION FOCUSED FROM
THE MT SHASTA AREA SOUTHWARD. IT IS PRESENTLY 38 DEGREES AND
RAINING AT MT SHASTA CITY. PRECIPITATION ALONG THE I-5 CORRIDOR
IN FAR SOUTH CENTRAL SISKIYOU COUNTY WILL LIKELY CHANGE OVER TO
SNOW LATE TONIGHT...SHORTLY AFTER 2 AM...WITH THE SNOW LEVEL
IN THAT LOCAL AREA DROPPING TO AROUND 3000 FEET WITH MORE INTENSE
PRECIPITATION RATES LOWERING THE SNOW LEVEL. SNOWFALL AMOUNTS
TONIGHT ARE FORECAST TO BE AROUND 1 TO 3 INCHES NEAR MT SHASTA.
MEANTIME, THERE IS A CHANCE OF LIGHT SNOW OVER THE SOUTHERN
OREGON CASCADES AND EAST SIDE WITH NOT MUCH MORE THAN A DUSTING AT
ELEVATIONS ABOVE 4500 FEET.

A MORE WIDESPREAD SHOWERY PATTERN WILL DEVELOP FOR OUR AREA ON
WEDNESDAY...ESPECIALLY ON THE WEST SIDE. THE SNOW LEVEL WILL
REMAIN AROUND 4500 FEET WITH 1 TO 3 INCHES OF SNOW POSSIBLE FOR
THE SOUTHERN OREGON SISKIYOU AND CASCADE MOUNTAINS. SHOWERS AND
SNOW SHOWERS WILL DIMINISH WEDNESDAY NIGHT AS A RIDGE BUILDS TO
THE COAST.

A FOCUS FOR THE NIGHT SHIFT WILL BE ON THE DETAILS OF WHAT LOOK TO
BE STRONGER FRONTS TO AFFECT OUR AREA THURSDAY EVENING INTO
FRIDAY AFTERNOON AND THEN SATURDAY INTO EARLY SUNDAY. THIS SECOND
SYSTEM ON THE WEEKEND HAS HIGHER UNCERTAINTY/MODEL SOLUTION
VARIABILITY.

&&

.AVIATION...BASED ON THE 17/00Z TAF CYCLE...CONDITIONS REMAIN VFR
ACROSS THE MEDFORD CWA THIS EVENING WITH THE NOTABLE EXCEPTION OF
MVFR CEILINGS OVER SOUTHERN SISKIYOU COUNTY WITH MOUNTAIN
OBSCURATION AND LIGHT TO MODERATE RAIN AND SNOW. ALSO...STRONG
SOUTHERLY LOW LEVEL WINDS WILL DIMINISH AFTER MIDNIGHT.
OVERNIGHT...AREAS OF MVFR CIGS IN PRECIPITATION WILL INCREASE
ALONG THE SOUTH COAST RANGE AND OVER MOST OF SISKIYOU COUNTY WITH
HIGHER TERRAIN OBSCURED. ISOLATED IFR CIGS/VSBYS IN LOW CLOUDS AND
FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE TONIGHT THROUGH
MID-MORNING WEDNESDAY...MAINLY IN THE UMPQUA BASIN.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE
OVER THE WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH
WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND
BEYOND 10NM OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY
THEN RETURN TO SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL
PUSH THROUGH ON THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING
GALE STRENGTH. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A
DOMINANT PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY AND LIKELY
REMAIN VERY HIGH INTO SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 216 PM PST TUE DEC 16 2014/

DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST WEDNESDAY FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST
     WEDNESDAY FOR PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
     WEDNESDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.

$$

DW/DW/SBN



000
FXUS66 KMFR 170530
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
930 PM PST TUE DEC 16 2014

.DISCUSSION...LOW PRESSURE OVER THE COASTAL WATERS WILL MOVE EAST
TO NORTHEAST TONIGHT WITH COLD FRONTAL PRECIPITATION FOCUSED FROM
THE MT SHASTA AREA SOUTHWARD. IT IS PRESENTLY 38 DEGREES AND
RAINING AT MT SHASTA CITY. PRECIPITATION ALONG THE I-5 CORRIDOR
IN FAR SOUTH CENTRAL SISKIYOU COUNTY WILL LIKELY CHANGE OVER TO
SNOW LATE TONIGHT...SHORTLY AFTER 2 AM...WITH THE SNOW LEVEL
IN THAT LOCAL AREA DROPPING TO AROUND 3000 FEET WITH MORE INTENSE
PRECIPITATION RATES LOWERING THE SNOW LEVEL. SNOWFALL AMOUNTS
TONIGHT ARE FORECAST TO BE AROUND 1 TO 3 INCHES NEAR MT SHASTA.
MEANTIME, THERE IS A CHANCE OF LIGHT SNOW OVER THE SOUTHERN
OREGON CASCADES AND EAST SIDE WITH NOT MUCH MORE THAN A DUSTING AT
ELEVATIONS ABOVE 4500 FEET.

A MORE WIDESPREAD SHOWERY PATTERN WILL DEVELOP FOR OUR AREA ON
WEDNESDAY...ESPECIALLY ON THE WEST SIDE. THE SNOW LEVEL WILL
REMAIN AROUND 4500 FEET WITH 1 TO 3 INCHES OF SNOW POSSIBLE FOR
THE SOUTHERN OREGON SISKIYOU AND CASCADE MOUNTAINS. SHOWERS AND
SNOW SHOWERS WILL DIMINISH WEDNESDAY NIGHT AS A RIDGE BUILDS TO
THE COAST.

A FOCUS FOR THE NIGHT SHIFT WILL BE ON THE DETAILS OF WHAT LOOK TO
BE STRONGER FRONTS TO AFFECT OUR AREA THURSDAY EVENING INTO
FRIDAY AFTERNOON AND THEN SATURDAY INTO EARLY SUNDAY. THIS SECOND
SYSTEM ON THE WEEKEND HAS HIGHER UNCERTAINTY/MODEL SOLUTION
VARIABILITY.

&&

.AVIATION...BASED ON THE 17/00Z TAF CYCLE...CONDITIONS REMAIN VFR
ACROSS THE MEDFORD CWA THIS EVENING WITH THE NOTABLE EXCEPTION OF
MVFR CEILINGS OVER SOUTHERN SISKIYOU COUNTY WITH MOUNTAIN
OBSCURATION AND LIGHT TO MODERATE RAIN AND SNOW. ALSO...STRONG
SOUTHERLY LOW LEVEL WINDS WILL DIMINISH AFTER MIDNIGHT.
OVERNIGHT...AREAS OF MVFR CIGS IN PRECIPITATION WILL INCREASE
ALONG THE SOUTH COAST RANGE AND OVER MOST OF SISKIYOU COUNTY WITH
HIGHER TERRAIN OBSCURED. ISOLATED IFR CIGS/VSBYS IN LOW CLOUDS AND
FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE TONIGHT THROUGH
MID-MORNING WEDNESDAY...MAINLY IN THE UMPQUA BASIN.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE
OVER THE WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH
WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND
BEYOND 10NM OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY
THEN RETURN TO SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL
PUSH THROUGH ON THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING
GALE STRENGTH. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A
DOMINANT PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY AND LIKELY
REMAIN VERY HIGH INTO SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 216 PM PST TUE DEC 16 2014/

DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST WEDNESDAY FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST
     WEDNESDAY FOR PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
     WEDNESDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.

$$

DW/DW/SBN



000
FXUS66 KMFR 170530
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
930 PM PST TUE DEC 16 2014

.DISCUSSION...LOW PRESSURE OVER THE COASTAL WATERS WILL MOVE EAST
TO NORTHEAST TONIGHT WITH COLD FRONTAL PRECIPITATION FOCUSED FROM
THE MT SHASTA AREA SOUTHWARD. IT IS PRESENTLY 38 DEGREES AND
RAINING AT MT SHASTA CITY. PRECIPITATION ALONG THE I-5 CORRIDOR
IN FAR SOUTH CENTRAL SISKIYOU COUNTY WILL LIKELY CHANGE OVER TO
SNOW LATE TONIGHT...SHORTLY AFTER 2 AM...WITH THE SNOW LEVEL
IN THAT LOCAL AREA DROPPING TO AROUND 3000 FEET WITH MORE INTENSE
PRECIPITATION RATES LOWERING THE SNOW LEVEL. SNOWFALL AMOUNTS
TONIGHT ARE FORECAST TO BE AROUND 1 TO 3 INCHES NEAR MT SHASTA.
MEANTIME, THERE IS A CHANCE OF LIGHT SNOW OVER THE SOUTHERN
OREGON CASCADES AND EAST SIDE WITH NOT MUCH MORE THAN A DUSTING AT
ELEVATIONS ABOVE 4500 FEET.

A MORE WIDESPREAD SHOWERY PATTERN WILL DEVELOP FOR OUR AREA ON
WEDNESDAY...ESPECIALLY ON THE WEST SIDE. THE SNOW LEVEL WILL
REMAIN AROUND 4500 FEET WITH 1 TO 3 INCHES OF SNOW POSSIBLE FOR
THE SOUTHERN OREGON SISKIYOU AND CASCADE MOUNTAINS. SHOWERS AND
SNOW SHOWERS WILL DIMINISH WEDNESDAY NIGHT AS A RIDGE BUILDS TO
THE COAST.

A FOCUS FOR THE NIGHT SHIFT WILL BE ON THE DETAILS OF WHAT LOOK TO
BE STRONGER FRONTS TO AFFECT OUR AREA THURSDAY EVENING INTO
FRIDAY AFTERNOON AND THEN SATURDAY INTO EARLY SUNDAY. THIS SECOND
SYSTEM ON THE WEEKEND HAS HIGHER UNCERTAINTY/MODEL SOLUTION
VARIABILITY.

&&

.AVIATION...BASED ON THE 17/00Z TAF CYCLE...CONDITIONS REMAIN VFR
ACROSS THE MEDFORD CWA THIS EVENING WITH THE NOTABLE EXCEPTION OF
MVFR CEILINGS OVER SOUTHERN SISKIYOU COUNTY WITH MOUNTAIN
OBSCURATION AND LIGHT TO MODERATE RAIN AND SNOW. ALSO...STRONG
SOUTHERLY LOW LEVEL WINDS WILL DIMINISH AFTER MIDNIGHT.
OVERNIGHT...AREAS OF MVFR CIGS IN PRECIPITATION WILL INCREASE
ALONG THE SOUTH COAST RANGE AND OVER MOST OF SISKIYOU COUNTY WITH
HIGHER TERRAIN OBSCURED. ISOLATED IFR CIGS/VSBYS IN LOW CLOUDS AND
FOG ARE POSSIBLE OVER THE WESTERN VALLEYS LATE TONIGHT THROUGH
MID-MORNING WEDNESDAY...MAINLY IN THE UMPQUA BASIN.

&&

.MARINE...UPDATED 800 PM PST TUE DEC 16 2014...LOW PRESSURE
OVER THE WATERS WILL MOVE NORTHEAST TONIGHT WITH INCREASING SOUTH
WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF CAPE BLANCO AND
BEYOND 10NM OFFSHORE. WINDS WILL VEER TO WESTERLY EARLY WEDNESDAY
THEN RETURN TO SOUTHERLY BY WEDNESDAY NIGHT. A STRONGER FRONT WILL
PUSH THROUGH ON THURSDAY WITH STRONG SOUTH WINDS POSSIBLY REACHING
GALE STRENGTH. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A
DOMINANT PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY AND LIKELY
REMAIN VERY HIGH INTO SATURDAY.

&&

.PREV DISCUSSION... /ISSUED 216 PM PST TUE DEC 16 2014/

DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY UNTIL 10 AM PST WEDNESDAY FOR
     CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST
     WEDNESDAY FOR PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
     WEDNESDAY FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.

$$

DW/DW/SBN



000
FXUS66 KPQR 170511
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 170511
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 170511
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 170511
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 170511
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
912 PM PST TUE DEC 16 2014

.SYNOPSIS...A CLOSED LOW JUST OFFSHORE WEST OF THE OR/CA BORDER WILL
SLOWLY WEAKEN AND PUSH NORTHWARD OVERNIGHT...EVENTUALLY MOVING
ONSHORE ALONG THE N OR/S WA COAST TOMORROW AFTERNOON. THIS WILL
MAINTAIN LIGHT SHOWER ACTIVITY...MAINLY OVER THE HIGHER TERRAIN
OVERNIGHT AND TOMORROW MORNING. AN UPPER LEVEL SHORTWAVE WILL PUSH
ONSHORE LATER TOMORROW...LIKELY BRINGING A PERIOD OF STEADIER
RAINFALL THROUGH EARLY THU MORNING. EXPECT A FAIRLY QUIET PERIOD FOR
MUCH OF THE DAY THU...BUT THEN A MORE ORGANIZED FRONT WILL BRING
GUSTY WINDS AND LARGE SURF TO THE COAST...WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL LIMIT SNOW TO THE
HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY RESULT IN SOME
SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING AND SATURDAY.
WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND. THERE IS THE
POTENTIAL FOR AN ATMOSPHERIC RIVER TYPE SET UP AND ASSOCIATED HEAVY
RAIN TO DEVELOP OVER THE WEEKEND INTO EARLY NEXT WEEK.

&&

.EVENING UPDATE...A LOW PRES CIRCULATION IS APPARENT ON SATELLITE AND
RADAR IMAGERY THIS EVENING JUST OFFSHORE OF THE CA/OR BORDER. WATER
VAPOR SATELLITE SHOWS MOISTURE SPREADING NORTHWARD FROM THIS SYSTEM
INTO NW OREGON AND SW WASHINGTON. THERE ARE ALSO LIGHT ECHOES SHOWING
UP ON RADAR OVER THE SOUTHERN AND WESTERN PORTIONS OF OUR FCST
AREA...BUT LITTLE TO NO RAIN IS REACHING THE GROUND AT THIS TIME.
EXPECT AS THE NIGHT GOES ON AND THE OFFSHORE LOW SLOWLY MOVES
NORTHEAST...WE WILL SEE LIGHT PRECIPITATION START TO REACH THE
SURFACE...ESPECIALLY OVER THE HIGHER TERRAIN. A WEAK VORT MAX WILL
ALSO MOVE ONSHORE EARLY WED MORNING...WHICH MAY HELP AID THE SHOWERS.

THE MAIN CHANGE TO THE FCST THIS EVENING WAS TO INCREASE POPS AND QPF
FROM THE 18Z WED TO 12Z THU TIME FRAME. THE CLOSED LOW JUST OFFSHORE
TONIGHT WILL SLOWLY WEAKEN AND PUSH ONSHORE AROUND MIDDAY TOMORROW.
MEANWHILE...THE SHORTWAVE NOW APPARENT ON WATER VAPOR SATELLITE
NEARING 45N 140W IS MODELED TO STRETCH OUT AND PUSH ONSHORE LATER
TOMORROW AFTERNOON AND EVENING. THE LOWER LEVEL MOISTURE ASSOCIATED
WITH THE SURFACE LOW COMBINED WITH THE UPPER LEVEL FORCING FROM THE
SHORTWAVE SHOULD DRIVE A PERIOD OF STEADIER PRECIP LATER TOMORROW
AND TOMORROW NIGHT. THE 00Z NAM AND GFS RUNS PICKED UP ON THIS
PERIOD OF ENHANCED PRECIP. THE VORT MAX PUSHES EAST OF THE CASCADES
BY 12Z THU...AFTER WHICH SHOWER ACTIVITY SHOULD DROP OFF
SIGNIFICANTLY. PYLE

.PREV DISC ISSUED 231 PM PST TUE DEC 17...

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MOIST SOUTHERLY FLOW ALOFT...WITH PLENTY OF MID AND
HIGH CLOUDS OVER REGION. DO HAVE AREAS OF MVFR CIGS ALONG THE
COAST AND WILL SEE THOSE PERSIST OVERNIGHT INTO WED AM. QUESTION
IS WHETHER OR NOT LOW CLOUDS REFORM S OF SALEM TONIGHT. HAVE
CLEARED OUT AT MOMENT...WITH STILL RATHER HIGH HUMIDITY. SO
SUSPECT WITH OCCASIONAL LIGHT RAIN THERE...WILL SEE AREAS OF IFR
STRATUS REFORM TONIGHT TO SOUTH OF KSLE.

KPDX AND APPROACHES...VFR WILL PERSIST TONIGHT AND WED...BUT CIGS
LOWER TO 5K FT LATER AFTER 09Z WITH OCCASIONAL LIGHT RAIN THROUGH
17Z. VFR WITH LOT OF MID AND HIGH CLOUDS ON WED.ROCKEY.
 &&

.MARINE...NOT MUCH CHANGE. GRADIENTS WEAKENING THIS EVENING AS
LOW HEADS INTO N CALIF. STILL...WILL GET A GUSTS TO 25 KT ON THE
OUTER SOUTH WATERS THIS EVENING. SEAS HOLDING AT 8 TO 9 FT.

NEXT SYSTEM NOW DEVELOPING WAY OFFSHORE BETWEEN 160W-170W. THIS
SYSTEM WILL BRING SOUTHERLY GALES TO THE WATERS LATER THU THROUGH
EARLY FRI AM. STILL SOME UNCERTAINTY ON EXACT TIMING AND DETAILS
BUT WILL BE VERY ACTIVE PERIOD. SEAS LIKELY TO PUSH BACK INTO THE
UPPER TEENS TO NEAR 20 FT BY FRI AM.

MORE FRONTS ARRIVE THIS WEEKEND INTO EARLY NEXT WEEK...WITH
SOUTHERLY GALES LIKELY AND ENHANCED SEAS.   ROCKEY.
&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FOR THU AND THU NIGHT ON ALL COASTAL WATERS.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
AND AGAIN 11 AM TO 4 PM WED.

&&


$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPDT 170508 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
908 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.UPDATE...RADAR SHOWS A BAND OF PRECIPITATION MOVING INTO
SOUTHWEST OREGON AT THIS TIME. THE PRECIPITATION WILL SPREAD EAST
OF THE CASCADES OVERNIGHT STARTING IN CENTRAL OREGON. LIGHT
NORTHERLY UPSLOPE WINDS OVER THE DESCHUTES PLATEAU PRODUCED DENSE
FOG/FREEZING FOG OVER NORTH CENTRAL AND CENTRAL OREGON. EXPECT THE
FOG TO PERSIST UNTIL THE APPROACHING DISTURBANCE WEAKENS THE
SURFACE INVERSIONS WEDNESDAY MORNING. THESE TRENDS ARE REFLECTED
IN CURRENT FORECAST.  COONFIELD

&&

.AVIATION...06Z TAFS...LOW STRATUS AND FZFG/FOG/BR WILL PERSIST NEAR
TAF SITES FOR THE NEXT 24 HOURS. KRDM AND KBDN WILL BE AT IFR/LIFR
LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN AROUND 13-15Z WHEN CEILINGS
WILL LIFT TO MVFR. SHOWERS WILL SWITCH TO RAIN AFTER 18Z. KDLS WILL
BE BELOW MINS (CIG LESS THAN 012) UNTIL 15Z. KPDT AND KALW WILL
HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN HAVE CIG
AROUND 010-015 UNTIL 15-17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. 76

&&

.PREV DISC... /ISSUED 354 PM PST TUE DEC 16 2014/

SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST WEDNESDAY ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76








000
FXUS66 KPDT 170508 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
908 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.UPDATE...RADAR SHOWS A BAND OF PRECIPITATION MOVING INTO
SOUTHWEST OREGON AT THIS TIME. THE PRECIPITATION WILL SPREAD EAST
OF THE CASCADES OVERNIGHT STARTING IN CENTRAL OREGON. LIGHT
NORTHERLY UPSLOPE WINDS OVER THE DESCHUTES PLATEAU PRODUCED DENSE
FOG/FREEZING FOG OVER NORTH CENTRAL AND CENTRAL OREGON. EXPECT THE
FOG TO PERSIST UNTIL THE APPROACHING DISTURBANCE WEAKENS THE
SURFACE INVERSIONS WEDNESDAY MORNING. THESE TRENDS ARE REFLECTED
IN CURRENT FORECAST.  COONFIELD

&&

.AVIATION...06Z TAFS...LOW STRATUS AND FZFG/FOG/BR WILL PERSIST NEAR
TAF SITES FOR THE NEXT 24 HOURS. KRDM AND KBDN WILL BE AT IFR/LIFR
LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN AROUND 13-15Z WHEN CEILINGS
WILL LIFT TO MVFR. SHOWERS WILL SWITCH TO RAIN AFTER 18Z. KDLS WILL
BE BELOW MINS (CIG LESS THAN 012) UNTIL 15Z. KPDT AND KALW WILL
HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN HAVE CIG
AROUND 010-015 UNTIL 15-17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. 76

&&

.PREV DISC... /ISSUED 354 PM PST TUE DEC 16 2014/

SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST WEDNESDAY ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76








000
FXUS66 KPDT 170508 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
908 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.UPDATE...RADAR SHOWS A BAND OF PRECIPITATION MOVING INTO
SOUTHWEST OREGON AT THIS TIME. THE PRECIPITATION WILL SPREAD EAST
OF THE CASCADES OVERNIGHT STARTING IN CENTRAL OREGON. LIGHT
NORTHERLY UPSLOPE WINDS OVER THE DESCHUTES PLATEAU PRODUCED DENSE
FOG/FREEZING FOG OVER NORTH CENTRAL AND CENTRAL OREGON. EXPECT THE
FOG TO PERSIST UNTIL THE APPROACHING DISTURBANCE WEAKENS THE
SURFACE INVERSIONS WEDNESDAY MORNING. THESE TRENDS ARE REFLECTED
IN CURRENT FORECAST.  COONFIELD

&&

.AVIATION...06Z TAFS...LOW STRATUS AND FZFG/FOG/BR WILL PERSIST NEAR
TAF SITES FOR THE NEXT 24 HOURS. KRDM AND KBDN WILL BE AT IFR/LIFR
LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN AROUND 13-15Z WHEN CEILINGS
WILL LIFT TO MVFR. SHOWERS WILL SWITCH TO RAIN AFTER 18Z. KDLS WILL
BE BELOW MINS (CIG LESS THAN 012) UNTIL 15Z. KPDT AND KALW WILL
HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN HAVE CIG
AROUND 010-015 UNTIL 15-17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. 76

&&

.PREV DISC... /ISSUED 354 PM PST TUE DEC 16 2014/

SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST WEDNESDAY ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76








000
FXUS66 KPDT 170508 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
908 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.UPDATE...RADAR SHOWS A BAND OF PRECIPITATION MOVING INTO
SOUTHWEST OREGON AT THIS TIME. THE PRECIPITATION WILL SPREAD EAST
OF THE CASCADES OVERNIGHT STARTING IN CENTRAL OREGON. LIGHT
NORTHERLY UPSLOPE WINDS OVER THE DESCHUTES PLATEAU PRODUCED DENSE
FOG/FREEZING FOG OVER NORTH CENTRAL AND CENTRAL OREGON. EXPECT THE
FOG TO PERSIST UNTIL THE APPROACHING DISTURBANCE WEAKENS THE
SURFACE INVERSIONS WEDNESDAY MORNING. THESE TRENDS ARE REFLECTED
IN CURRENT FORECAST.  COONFIELD

&&

.AVIATION...06Z TAFS...LOW STRATUS AND FZFG/FOG/BR WILL PERSIST NEAR
TAF SITES FOR THE NEXT 24 HOURS. KRDM AND KBDN WILL BE AT IFR/LIFR
LEVELS UNTIL LIGHT SNOW SHOWERS MOVE IN AROUND 13-15Z WHEN CEILINGS
WILL LIFT TO MVFR. SHOWERS WILL SWITCH TO RAIN AFTER 18Z. KDLS WILL
BE BELOW MINS (CIG LESS THAN 012) UNTIL 15Z. KPDT AND KALW WILL
HAVE CIGS BELOW 005 THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN HAVE CIG
AROUND 010-015 UNTIL 15-17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. 76

&&

.PREV DISC... /ISSUED 354 PM PST TUE DEC 16 2014/

SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST WEDNESDAY ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76








000
FXUS66 KPDT 170430
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
830 PM PST TUE DEC 16 2014

.UPDATE...RADAR SHOWS A BAND OF PRECIPITATION MOVING INTO
SOUTHWEST OREGON AT THIS TIME. THE PRECIPITATION WILL SPREAD EAST
OF THE CASCADES OVERNIGHT STARTING IN CENTRAL OREGON. LIGHT
NORTHERLY UPSLOPE WINDS OVER THE DESCHUTES PLATEAU PRODUCED DENSE
FOG/FREEZING FOG OVER NORTH CENTRAL AND CENTRAL OREGON. EXPECT THE
FOG TO PERSIST UNTIL THE APPROACHING DISTURBANCE WEAKENS THE
SURFACE INVERSIONS WEDNESDAY MORNING. THESE TRENDS ARE REFLECTED
IN CURRENT FORECAST.  COONFIELD

&&

.PREV DISC... /ISSUED 354 PM PST TUE DEC 16 2014/

SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY

AVIATION...00Z TAFS...ONE WEAK SYSTEM HAS EXITED THE AREA AND
ANOTHER WILL ENTER THE AREA FROM THE SOUTH LATER TONIGHT AND SLOWLY
MOVE ACROSS THE AREA TOMORROW. LOW STRATUS AND FZFG/FOG/BR WILL
CONTINUE TO PLAGUE TAF SITES UNTIL THE SYSTEM MOVES INTO THE AREA.
KRDM AND KBDN WILL BE AT IFR/LIFR LEVELS UNTIL LIGHT SNOW SHOWERS
MOVE IN AROUND 10Z WHEN CEILINGS WILL LIFT TO MVFR. SHOWERS WILL
SWITCH TO RAIN AFTER 18Z. KDLS WILL BE AT MVFR LEVELS WITH LIGHT
RAIN SHOWERS POSSIBLE FROM 13Z TO 21Z. KPDT AND KALW WILL BE AT
MVFR/IFR/LIFR LEVELS THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN AT
MVFR/IFR LEVELS UNTIL 17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...DENSE FOG ADVISORY UNTIL 10 AM PST WEDNESDAY ORZ510-511.

WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76





000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD



000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD




000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD




000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD




000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD




000
FXUS65 KBOI 170356
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
856 PM MST TUE DEC 16 2014

.DISCUSSION...UPPER LEVEL SYSTEM EXITING CENTRAL IDAHO IS LEAVING
WIDESPREAD STRATUS IN ITS WAKE PER 11-3.9 MICRON IMAGERY. STRATUS
IS PATCHY ACROSS NE AND EAST CENTRAL OREGON WAS WIDESPREAD ACROSS
SW ID EXCEPT OWYHEE COUNTY. THE NEXT UPPER LEVEL SYSTEM WAS OVER W
OREGON TO NEAR THE LAKE-HARNEY COUNTY LINE. EXPECT STRATUS TO
EXPAND OVERNIGHT TO AREAS BELOW 4K FT MSL WHICH INCLUDES MUCH OF
THE MALHEUR AND POWDER RIVER BASINS. EXPECT THE NEXT SYSTEM TO
LIFT NORTH ACROSS OREGON OVERNIGHT. THIS IS IN LINE WITH RECENT
HRRR RUNS. STRATUS MAY HAVE LIGHT FLURRIES SO PLAN TO KEEP LOW
CENTRAL IDAHO POPS 6-12Z FOR THAT. FORECAST ON TRACK WITH A MINOR
UPDATE TO RAISE MIN TEMPS UNDER STRATUS LAYER.

&&

.AVIATION...MVFR/IFR SNOW SHOWERS IN THE WEISER BASIN THROUGH THE
WEST CENTRAL AND BOISE MOUNTAINS ENDING BY 06Z TONIGHT. IFR STRATUS
AND FOG AT KBKE...KBNO...KMYL AND THE WESTERN MAGIC VALLEY WILL
MOST LIKELY LAST THROUGH WEDNESDAY MORNING. SFC WINDS ARE VARIABLE
LESS THAN 10 KTS. WINDS ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP
TO 10KFT.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....JS
PREV SHORT TERM...EP
PREV LONG TERM....SP/DD




000
FXUS66 KPDT 162354 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
354 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...00Z TAFS...ONE WEAK SYSTEM HAS EXITED THE AREA AND
ANOTHER WILL ENTER THE AREA FROM THE SOUTH LATER TONIGHT AND SLOWLY
MOVE ACROSS THE AREA TOMORROW. LOW STRATUS AND FZFG/FG/BR WILL
CONTINUE TO PLAGUE TAF SITES UNTIL THE SYSTEM MOVES INTO THE AREA.
KRDM AND KBDN WILL BE AT IFR/LIFR LEVELS UNTIL LIGHT SNOW SHOWERS
MOVE IN AROUND 10Z WHEN CEILINGS WILL LIFT TO MVFR. SHOWERS WILL
SWITCH TO RAIN AFTER 18Z. KDLS WILL BE AT MVFR LEVELS WITH LIGHT
RAIN SHOWERS POSSIBLE FROM 13Z TO 21Z. KPDT AND KALW WILL BE AT
MVFR/IFR/LIFR LEVELS THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN AT
MVFR/IFR LEVELS UNTIL 17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83











000
FXUS66 KPDT 162354 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
354 PM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...00Z TAFS...ONE WEAK SYSTEM HAS EXITED THE AREA AND
ANOTHER WILL ENTER THE AREA FROM THE SOUTH LATER TONIGHT AND SLOWLY
MOVE ACROSS THE AREA TOMORROW. LOW STRATUS AND FZFG/FG/BR WILL
CONTINUE TO PLAGUE TAF SITES UNTIL THE SYSTEM MOVES INTO THE AREA.
KRDM AND KBDN WILL BE AT IFR/LIFR LEVELS UNTIL LIGHT SNOW SHOWERS
MOVE IN AROUND 10Z WHEN CEILINGS WILL LIFT TO MVFR. SHOWERS WILL
SWITCH TO RAIN AFTER 18Z. KDLS WILL BE AT MVFR LEVELS WITH LIGHT
RAIN SHOWERS POSSIBLE FROM 13Z TO 21Z. KPDT AND KALW WILL BE AT
MVFR/IFR/LIFR LEVELS THROUGH 15Z WHEN RAIN SHOWERS WILL DEVELOP AND
IMPROVE CONDITIONS TO MVFR/VFR. KPSC AND KYKM WILL REMAIN AT
MVFR/IFR LEVELS UNTIL 17Z WHEN RAIN SHOWERS WILL HELP IMPROVE
CONDITIONS TO MVFR/VFR. WINDS WILL REMAIN BELOW 10 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83












000
FXUS66 KPQR 162231
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
231 PM PST TUE DEC 16 2014

.SYNOPSIS...THERE WILL BE A BREAK IN RAIN THIS AFTERNOON BEFORE RAIN
ASSOCIATED WITH A LOW WEST OF THE CENTRAL OREGON COAST...MOVES SOUTH
TO NORTH THIS EVENING THROUGH WEDNESDAY MORNING. SHOWERS WILL
PRIMARILY BE OVER THE HIGHER TERRAIN. AN UPPER TROUGH WILL MAINTAIN A
CHANCE FOR SHOWERS THROUGH WEDNESDAY EVENING. A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...WITH  RAIN
SPREADING INLAND THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL
LIMIT SNOW TO THE HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY
RESULT IN SOME SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING
AND SATURDAY. A WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MAINLY VFR CONDITIONS ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH A COUPLE NOTABLE EXCEPTIONS. IFR/LIFR CIGS
DEVELOPED THIS MORNING IN THE WILLAMETTE VALLEY KSLE SOUTHWARD...
AND HAVE LINGERED ALL DAY DUE TO LIGHT N-NE FLOW JAMMING THE LOW
CLOUDS AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. KSLE
APPEARS TO BE ON THE NORTHERN FRINGE OF THESE LOW CLOUDS...AND
WILL LIKELY REMAIN SO THROUGH THIS EVENING. CIGS WILL PROBABLY
DROP BACK DOWN TO NEAR THE DECK IN THESE AREAS TONIGHT AS -RA
DEVELOPS WITH OUR NEXT FRONTAL SYSTEM AND MOISTENS UP THE LOW
LEVEL AIR MASS.

ALSO EASTERLY UPSLOPE FLOW CAUSING MOUNTAIN OBSCURATIONS ALONG
THE EAST SLOPES AND CREST OF THE CASCADES...AND WILL LIKELY
CONTINUE TO DO SO OVERNIGHT TONIGHT.

WILL SEE AREAS -RA SPREAD NORTHWARD ACROSS MUCH OF THE FORECAST
AREA LATER TONIGHT...BUT IT APPEARS CIGS WILL GENERALLY REMAIN VFR
UNLESS OTHERWISE STATED ABOVE.WEAGLE

KPDX AND APPROACHES...VFR CIGS LIKELY REMAIN AT OR ABOVE 5 K FT
THROUGH THIS EVENING. SOME -RA IS POSSIBLE LATER TONIGHT AS
MOISTURE ASSOCIATED WITH AN OCCLUDED FRONT SPREADS NORTHWARD.
HOWEVER IT APPEARS CIGS SHOULD REMAIN VFR. LIGHT TO MODERATE
EASTERLY SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...VISIBLE SATELLITE IMAGERY SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 150 NM WEST OF CRESCENT CITY CA. THIS SYSTEM
APPEARS TO HAVE REACHED ITS MAXIMUM STRENGTH WITH A CENTRAL
PRESSURE AROUND 995 MB. FORECAST MODELS APPEAR TO HAVE GENERALLY
CAUGHT UP WITH THE STRENGTH OF THIS SYSTEM AFTER LAGGING BEHIND
EARLIER TODAY. THE LOW WILL DRIFT E-NE TONIGHT...PUSHING INTO WRN
OREGON BY WED. IT APPEARS E-NE WINDS CURLING AROUND THIS LOW WILL
BE ENOUGH TO PUSH GUSTS TO 25 KT IN OUR FAR SW WATERS...SO ISSUED
A SCA FOR WINDS IN THIS AREA THIS EVENING. AS THE LOW WEAKENS...
WINDS ASSOCIATED WITH THIS SYSTEM SHOULD WEAKEN AS WELL.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 160W-170W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
AFTER COORDINATION WITH WFO SEATTLE...DECIDED CONFIDENCE WAS HIGH
ENOUGH TO WARRANT A GALE WATCH FOR THIS SYSTEM. 12Z ECMWF/GFS SHOW
THIS SYSTEM TAKING A NEAR-IDEAL TRACK AND SPEED FOR DYNAMIC
FETCH...AND THIS SHOWS IN THE WAVE MODELS. ENP GUIDANCE SUGGESTS
A SOLID 17-21 FT SWELL WITH A DOMINANT PERIOD OF 16-20 SECONDS
FOLLOWS THE FRONT...PROBABLY ENOUGH TO WARRANT A HIGH SURF
ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO
     MIDNIGHT PST TONIGHT FOR WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM TO
     5 PM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 162231
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
231 PM PST TUE DEC 16 2014

.SYNOPSIS...THERE WILL BE A BREAK IN RAIN THIS AFTERNOON BEFORE RAIN
ASSOCIATED WITH A LOW WEST OF THE CENTRAL OREGON COAST...MOVES SOUTH
TO NORTH THIS EVENING THROUGH WEDNESDAY MORNING. SHOWERS WILL
PRIMARILY BE OVER THE HIGHER TERRAIN. AN UPPER TROUGH WILL MAINTAIN A
CHANCE FOR SHOWERS THROUGH WEDNESDAY EVENING. A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...WITH  RAIN
SPREADING INLAND THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL
LIMIT SNOW TO THE HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY
RESULT IN SOME SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING
AND SATURDAY. A WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MAINLY VFR CONDITIONS ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH A COUPLE NOTABLE EXCEPTIONS. IFR/LIFR CIGS
DEVELOPED THIS MORNING IN THE WILLAMETTE VALLEY KSLE SOUTHWARD...
AND HAVE LINGERED ALL DAY DUE TO LIGHT N-NE FLOW JAMMING THE LOW
CLOUDS AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. KSLE
APPEARS TO BE ON THE NORTHERN FRINGE OF THESE LOW CLOUDS...AND
WILL LIKELY REMAIN SO THROUGH THIS EVENING. CIGS WILL PROBABLY
DROP BACK DOWN TO NEAR THE DECK IN THESE AREAS TONIGHT AS -RA
DEVELOPS WITH OUR NEXT FRONTAL SYSTEM AND MOISTENS UP THE LOW
LEVEL AIR MASS.

ALSO EASTERLY UPSLOPE FLOW CAUSING MOUNTAIN OBSCURATIONS ALONG
THE EAST SLOPES AND CREST OF THE CASCADES...AND WILL LIKELY
CONTINUE TO DO SO OVERNIGHT TONIGHT.

WILL SEE AREAS -RA SPREAD NORTHWARD ACROSS MUCH OF THE FORECAST
AREA LATER TONIGHT...BUT IT APPEARS CIGS WILL GENERALLY REMAIN VFR
UNLESS OTHERWISE STATED ABOVE.WEAGLE

KPDX AND APPROACHES...VFR CIGS LIKELY REMAIN AT OR ABOVE 5 K FT
THROUGH THIS EVENING. SOME -RA IS POSSIBLE LATER TONIGHT AS
MOISTURE ASSOCIATED WITH AN OCCLUDED FRONT SPREADS NORTHWARD.
HOWEVER IT APPEARS CIGS SHOULD REMAIN VFR. LIGHT TO MODERATE
EASTERLY SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...VISIBLE SATELLITE IMAGERY SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 150 NM WEST OF CRESCENT CITY CA. THIS SYSTEM
APPEARS TO HAVE REACHED ITS MAXIMUM STRENGTH WITH A CENTRAL
PRESSURE AROUND 995 MB. FORECAST MODELS APPEAR TO HAVE GENERALLY
CAUGHT UP WITH THE STRENGTH OF THIS SYSTEM AFTER LAGGING BEHIND
EARLIER TODAY. THE LOW WILL DRIFT E-NE TONIGHT...PUSHING INTO WRN
OREGON BY WED. IT APPEARS E-NE WINDS CURLING AROUND THIS LOW WILL
BE ENOUGH TO PUSH GUSTS TO 25 KT IN OUR FAR SW WATERS...SO ISSUED
A SCA FOR WINDS IN THIS AREA THIS EVENING. AS THE LOW WEAKENS...
WINDS ASSOCIATED WITH THIS SYSTEM SHOULD WEAKEN AS WELL.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 160W-170W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
AFTER COORDINATION WITH WFO SEATTLE...DECIDED CONFIDENCE WAS HIGH
ENOUGH TO WARRANT A GALE WATCH FOR THIS SYSTEM. 12Z ECMWF/GFS SHOW
THIS SYSTEM TAKING A NEAR-IDEAL TRACK AND SPEED FOR DYNAMIC
FETCH...AND THIS SHOWS IN THE WAVE MODELS. ENP GUIDANCE SUGGESTS
A SOLID 17-21 FT SWELL WITH A DOMINANT PERIOD OF 16-20 SECONDS
FOLLOWS THE FRONT...PROBABLY ENOUGH TO WARRANT A HIGH SURF
ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO
     MIDNIGHT PST TONIGHT FOR WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM TO
     5 PM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 162231
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
231 PM PST TUE DEC 16 2014

.SYNOPSIS...THERE WILL BE A BREAK IN RAIN THIS AFTERNOON BEFORE RAIN
ASSOCIATED WITH A LOW WEST OF THE CENTRAL OREGON COAST...MOVES SOUTH
TO NORTH THIS EVENING THROUGH WEDNESDAY MORNING. SHOWERS WILL
PRIMARILY BE OVER THE HIGHER TERRAIN. AN UPPER TROUGH WILL MAINTAIN A
CHANCE FOR SHOWERS THROUGH WEDNESDAY EVENING. A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...WITH  RAIN
SPREADING INLAND THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL
LIMIT SNOW TO THE HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY
RESULT IN SOME SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING
AND SATURDAY. A WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MAINLY VFR CONDITIONS ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH A COUPLE NOTABLE EXCEPTIONS. IFR/LIFR CIGS
DEVELOPED THIS MORNING IN THE WILLAMETTE VALLEY KSLE SOUTHWARD...
AND HAVE LINGERED ALL DAY DUE TO LIGHT N-NE FLOW JAMMING THE LOW
CLOUDS AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. KSLE
APPEARS TO BE ON THE NORTHERN FRINGE OF THESE LOW CLOUDS...AND
WILL LIKELY REMAIN SO THROUGH THIS EVENING. CIGS WILL PROBABLY
DROP BACK DOWN TO NEAR THE DECK IN THESE AREAS TONIGHT AS -RA
DEVELOPS WITH OUR NEXT FRONTAL SYSTEM AND MOISTENS UP THE LOW
LEVEL AIR MASS.

ALSO EASTERLY UPSLOPE FLOW CAUSING MOUNTAIN OBSCURATIONS ALONG
THE EAST SLOPES AND CREST OF THE CASCADES...AND WILL LIKELY
CONTINUE TO DO SO OVERNIGHT TONIGHT.

WILL SEE AREAS -RA SPREAD NORTHWARD ACROSS MUCH OF THE FORECAST
AREA LATER TONIGHT...BUT IT APPEARS CIGS WILL GENERALLY REMAIN VFR
UNLESS OTHERWISE STATED ABOVE.WEAGLE

KPDX AND APPROACHES...VFR CIGS LIKELY REMAIN AT OR ABOVE 5 K FT
THROUGH THIS EVENING. SOME -RA IS POSSIBLE LATER TONIGHT AS
MOISTURE ASSOCIATED WITH AN OCCLUDED FRONT SPREADS NORTHWARD.
HOWEVER IT APPEARS CIGS SHOULD REMAIN VFR. LIGHT TO MODERATE
EASTERLY SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...VISIBLE SATELLITE IMAGERY SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 150 NM WEST OF CRESCENT CITY CA. THIS SYSTEM
APPEARS TO HAVE REACHED ITS MAXIMUM STRENGTH WITH A CENTRAL
PRESSURE AROUND 995 MB. FORECAST MODELS APPEAR TO HAVE GENERALLY
CAUGHT UP WITH THE STRENGTH OF THIS SYSTEM AFTER LAGGING BEHIND
EARLIER TODAY. THE LOW WILL DRIFT E-NE TONIGHT...PUSHING INTO WRN
OREGON BY WED. IT APPEARS E-NE WINDS CURLING AROUND THIS LOW WILL
BE ENOUGH TO PUSH GUSTS TO 25 KT IN OUR FAR SW WATERS...SO ISSUED
A SCA FOR WINDS IN THIS AREA THIS EVENING. AS THE LOW WEAKENS...
WINDS ASSOCIATED WITH THIS SYSTEM SHOULD WEAKEN AS WELL.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 160W-170W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
AFTER COORDINATION WITH WFO SEATTLE...DECIDED CONFIDENCE WAS HIGH
ENOUGH TO WARRANT A GALE WATCH FOR THIS SYSTEM. 12Z ECMWF/GFS SHOW
THIS SYSTEM TAKING A NEAR-IDEAL TRACK AND SPEED FOR DYNAMIC
FETCH...AND THIS SHOWS IN THE WAVE MODELS. ENP GUIDANCE SUGGESTS
A SOLID 17-21 FT SWELL WITH A DOMINANT PERIOD OF 16-20 SECONDS
FOLLOWS THE FRONT...PROBABLY ENOUGH TO WARRANT A HIGH SURF
ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO
     MIDNIGHT PST TONIGHT FOR WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM TO
     5 PM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 162231
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
231 PM PST TUE DEC 16 2014

.SYNOPSIS...THERE WILL BE A BREAK IN RAIN THIS AFTERNOON BEFORE RAIN
ASSOCIATED WITH A LOW WEST OF THE CENTRAL OREGON COAST...MOVES SOUTH
TO NORTH THIS EVENING THROUGH WEDNESDAY MORNING. SHOWERS WILL
PRIMARILY BE OVER THE HIGHER TERRAIN. AN UPPER TROUGH WILL MAINTAIN A
CHANCE FOR SHOWERS THROUGH WEDNESDAY EVENING. A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...WITH  RAIN
SPREADING INLAND THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL
LIMIT SNOW TO THE HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY
RESULT IN SOME SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING
AND SATURDAY. A WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MAINLY VFR CONDITIONS ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH A COUPLE NOTABLE EXCEPTIONS. IFR/LIFR CIGS
DEVELOPED THIS MORNING IN THE WILLAMETTE VALLEY KSLE SOUTHWARD...
AND HAVE LINGERED ALL DAY DUE TO LIGHT N-NE FLOW JAMMING THE LOW
CLOUDS AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. KSLE
APPEARS TO BE ON THE NORTHERN FRINGE OF THESE LOW CLOUDS...AND
WILL LIKELY REMAIN SO THROUGH THIS EVENING. CIGS WILL PROBABLY
DROP BACK DOWN TO NEAR THE DECK IN THESE AREAS TONIGHT AS -RA
DEVELOPS WITH OUR NEXT FRONTAL SYSTEM AND MOISTENS UP THE LOW
LEVEL AIR MASS.

ALSO EASTERLY UPSLOPE FLOW CAUSING MOUNTAIN OBSCURATIONS ALONG
THE EAST SLOPES AND CREST OF THE CASCADES...AND WILL LIKELY
CONTINUE TO DO SO OVERNIGHT TONIGHT.

WILL SEE AREAS -RA SPREAD NORTHWARD ACROSS MUCH OF THE FORECAST
AREA LATER TONIGHT...BUT IT APPEARS CIGS WILL GENERALLY REMAIN VFR
UNLESS OTHERWISE STATED ABOVE.WEAGLE

KPDX AND APPROACHES...VFR CIGS LIKELY REMAIN AT OR ABOVE 5 K FT
THROUGH THIS EVENING. SOME -RA IS POSSIBLE LATER TONIGHT AS
MOISTURE ASSOCIATED WITH AN OCCLUDED FRONT SPREADS NORTHWARD.
HOWEVER IT APPEARS CIGS SHOULD REMAIN VFR. LIGHT TO MODERATE
EASTERLY SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...VISIBLE SATELLITE IMAGERY SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 150 NM WEST OF CRESCENT CITY CA. THIS SYSTEM
APPEARS TO HAVE REACHED ITS MAXIMUM STRENGTH WITH A CENTRAL
PRESSURE AROUND 995 MB. FORECAST MODELS APPEAR TO HAVE GENERALLY
CAUGHT UP WITH THE STRENGTH OF THIS SYSTEM AFTER LAGGING BEHIND
EARLIER TODAY. THE LOW WILL DRIFT E-NE TONIGHT...PUSHING INTO WRN
OREGON BY WED. IT APPEARS E-NE WINDS CURLING AROUND THIS LOW WILL
BE ENOUGH TO PUSH GUSTS TO 25 KT IN OUR FAR SW WATERS...SO ISSUED
A SCA FOR WINDS IN THIS AREA THIS EVENING. AS THE LOW WEAKENS...
WINDS ASSOCIATED WITH THIS SYSTEM SHOULD WEAKEN AS WELL.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 160W-170W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
AFTER COORDINATION WITH WFO SEATTLE...DECIDED CONFIDENCE WAS HIGH
ENOUGH TO WARRANT A GALE WATCH FOR THIS SYSTEM. 12Z ECMWF/GFS SHOW
THIS SYSTEM TAKING A NEAR-IDEAL TRACK AND SPEED FOR DYNAMIC
FETCH...AND THIS SHOWS IN THE WAVE MODELS. ENP GUIDANCE SUGGESTS
A SOLID 17-21 FT SWELL WITH A DOMINANT PERIOD OF 16-20 SECONDS
FOLLOWS THE FRONT...PROBABLY ENOUGH TO WARRANT A HIGH SURF
ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO
     MIDNIGHT PST TONIGHT FOR WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM TO
     5 PM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 162231
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
231 PM PST TUE DEC 16 2014

.SYNOPSIS...THERE WILL BE A BREAK IN RAIN THIS AFTERNOON BEFORE RAIN
ASSOCIATED WITH A LOW WEST OF THE CENTRAL OREGON COAST...MOVES SOUTH
TO NORTH THIS EVENING THROUGH WEDNESDAY MORNING. SHOWERS WILL
PRIMARILY BE OVER THE HIGHER TERRAIN. AN UPPER TROUGH WILL MAINTAIN A
CHANCE FOR SHOWERS THROUGH WEDNESDAY EVENING. A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...WITH  RAIN
SPREADING INLAND THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS WILL
LIMIT SNOW TO THE HIGHEST PEAKS...BUT COLDER AIR BEHIND THE FRONT MAY
RESULT IN SOME SNOW SHOWERS FOR THE CASCADES PASSES FRIDAY EVENING
AND SATURDAY. A WARMER AND MOISTER WEATHER IS EXPECTED THIS WEEKEND.

&&

.SHORT TERM...TONIGHT THROUGH FRIDAY...SHOWERS HAVE PRETTY MUCH ENDED
OVER THE PORTLAND FORECAST AREA EARLY THIS AFTERNOON...EXCEPT FOR
VERY INFREQUENT ISOLATED SHOWER OVER THE SW WASHINGTON CASCADES.
SATELLITE IMAGERY SHOWS A SURFACE LOW AROUND 150 MILES WEST OF THE
SOUTHERN OREGON COAST...NEAR 42N 127W. THE HIGHER RESOLUTION
MODELS...HRRR AND RAP INITIALIZE BEST WITH THE LOW AND FORECAST RAIN
MOVING NORTH INTO LANE COUNTY SLIGHTLY EARLIER THAN THE OTHER MODELS.
HAVE TRENDED TOWARDS THIS EARLIER ARRIVAL...BUT ONLY HAVE FAIR
CONFIDENCE THAT THE TIMING WILL PAN OUT. ANY RAIN LATE THIS AFTERNOON
SHOULD BE FAIRLY LIGHT AND REMAIN WEST OF THE SOUTH AND CENTRAL
WILLAMETTE VALLEY.

THE LOW WILL MOVE CLOSER TO THE SOUTHERN OREGON COAST LATE THIS
AFTERNOON AND EVENING THEN MOVE ONTO THE CENTRAL OREGON COAST AS AN
UPPER TROUGH LATE TONIGHT...WITH SHOWERS MAINLY OVER THE HIGHER
TERRAIN THROUGH WEDNESDAY MORNING. SOME CLEARING EARLY WED MORNING
MAY RESULT IN SHALLOW FOG AND LOW CLOUDS IN SOME OF THE INTERIOR
VALLEYS...MAINLY SOUTH OF SALEM.

EASTERLY WINDS HAVE HELD ON TODAY WITH A TROUTDALE TO DALLES PRESSURE
GRADIENT HOLDING AROUND 5 MB. THIS GRADIENT SHOULD TIGHTEN A LITTLE
THIS EVENING AS THE LOW MOVES CLOSER TO THE COAST AND MAINTAIN GUSTS
AROUND 30 MPH THROUGH THE WESTERN COLUMBIA RIVER GORGE.

SHOWERS WILL CONTINUE WEDNESDAY...MAINLY FOR THE HIGHER TERRAIN AS
THE PARENT UPPER LEVEL TROUGH MOVES OVER THE PACIFIC NW. SHOWERS
SHOULD END OVERNIGHT AS AN UPPER RIDGE BUILDS OVER THE AREA AND
EXPECT THAT CLEARING SKIES AND LIGHT WINDS WILL LEAD TO SHALLOW FOG
FOR THE INTERIOR VALLEYS EARLY THURSDAY MORNING. MOST OF THURSDAY
WILL BE DRY WITH AN INCREASE OF MID AN HIGH LEVEL CLOUDS IN THE
AFTERNOON.

MODELS ARE IN GOOD AGREEMENT THAT A WELL ORGANIZED FRONT WILL BRING
GUSTY WINDS TO THE COAST THURSDAY EVENING WITH RAIN SPREADING INLAND
THURSDAY NIGHT AND FRIDAY. PRECIPITABLE WATER IS EXPECTED TO BE NEAR
AN INCH AND AN APPROACHING JET STREAK SHOULD PROVIDE GOOD LIFT AND
EXPECT THE HIGHEST RAINFALL TOTALS OF 0.75 TO 1 INCH ACROSS THE
COAST AND COAST RANGE THURSDAY NIGHT THROUGH FRIDAY MORNING. OTHER
AREAS SHOULD SEE BETWEEN 0.4 AND 0.60 INCH OF RAIN. SNOW LEVELS
SHOULD REMAIN ABOVE 5000 FEET DURING THE PEAK RAIN PERIOD...BUT LOWER
TO NEAR OR BELOW THE CASCADE PASSES BEHIND THE FRONT FRIDAY
AFTERNOON.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...A BROAD RIDGE OF HIGH
PRESSURE OVER THE WESTERN U.S. FLATTENS AS A STRONG LOW PRESSURE
SYSTEM OVER THE GULF OF ALASKA MOVES INLAND TO OUR NORTH. AS THIS
TROUGH MOVES ON SHORE SATURDAY...THE ASSOCIATED COLD FRONT MOVES
ONSHORE AND STALLS EAST-TO-WEST ACROSS NORTHWEST OREGON AND
SOUTHWEST WASHINGTON. THIS PUTS OUR AREA IN THE PATH OF RAIN
STARTING SATURDAY THROUGH MONDAY. SOME UNCERTAINTY EXISTS IN WHERE
THIS BOUNDARY WILL SET UP...WHICH WILL DETERMINE HOW MUCH RAINFALL
WE WILL GET. ON TUESDAY...GEFS ENSEMBLE SPAGHETTI PLOTS GET MESSY
AND SIGNIFICANT DIFFERENCES START TO SHOW UP BETWEEN THE GFS AND
ECMWF...DECREASING CONFIDENCE ON HOW THE REST OF THE WEEK WILL SHAPE
UP.  AS OF NOW...THE MOST COMMON SOLUTION IS THAT HIGH PRESSURE
RIDGING WILL START TO BUILD BACK OVER THE WESTERN U.S. WHICH
SUGGESTS DRIER WEATHER STARTING TUESDAY...THOUGH UNCERTAINTY IS VERY
HIGH. -MCCOY

&&

.AVIATION...MAINLY VFR CONDITIONS ACROSS THE FORECAST AREA THIS
AFTERNOON...WITH A COUPLE NOTABLE EXCEPTIONS. IFR/LIFR CIGS
DEVELOPED THIS MORNING IN THE WILLAMETTE VALLEY KSLE SOUTHWARD...
AND HAVE LINGERED ALL DAY DUE TO LIGHT N-NE FLOW JAMMING THE LOW
CLOUDS AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. KSLE
APPEARS TO BE ON THE NORTHERN FRINGE OF THESE LOW CLOUDS...AND
WILL LIKELY REMAIN SO THROUGH THIS EVENING. CIGS WILL PROBABLY
DROP BACK DOWN TO NEAR THE DECK IN THESE AREAS TONIGHT AS -RA
DEVELOPS WITH OUR NEXT FRONTAL SYSTEM AND MOISTENS UP THE LOW
LEVEL AIR MASS.

ALSO EASTERLY UPSLOPE FLOW CAUSING MOUNTAIN OBSCURATIONS ALONG
THE EAST SLOPES AND CREST OF THE CASCADES...AND WILL LIKELY
CONTINUE TO DO SO OVERNIGHT TONIGHT.

WILL SEE AREAS -RA SPREAD NORTHWARD ACROSS MUCH OF THE FORECAST
AREA LATER TONIGHT...BUT IT APPEARS CIGS WILL GENERALLY REMAIN VFR
UNLESS OTHERWISE STATED ABOVE.WEAGLE

KPDX AND APPROACHES...VFR CIGS LIKELY REMAIN AT OR ABOVE 5 K FT
THROUGH THIS EVENING. SOME -RA IS POSSIBLE LATER TONIGHT AS
MOISTURE ASSOCIATED WITH AN OCCLUDED FRONT SPREADS NORTHWARD.
HOWEVER IT APPEARS CIGS SHOULD REMAIN VFR. LIGHT TO MODERATE
EASTERLY SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...VISIBLE SATELLITE IMAGERY SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 150 NM WEST OF CRESCENT CITY CA. THIS SYSTEM
APPEARS TO HAVE REACHED ITS MAXIMUM STRENGTH WITH A CENTRAL
PRESSURE AROUND 995 MB. FORECAST MODELS APPEAR TO HAVE GENERALLY
CAUGHT UP WITH THE STRENGTH OF THIS SYSTEM AFTER LAGGING BEHIND
EARLIER TODAY. THE LOW WILL DRIFT E-NE TONIGHT...PUSHING INTO WRN
OREGON BY WED. IT APPEARS E-NE WINDS CURLING AROUND THIS LOW WILL
BE ENOUGH TO PUSH GUSTS TO 25 KT IN OUR FAR SW WATERS...SO ISSUED
A SCA FOR WINDS IN THIS AREA THIS EVENING. AS THE LOW WEAKENS...
WINDS ASSOCIATED WITH THIS SYSTEM SHOULD WEAKEN AS WELL.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 160W-170W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
AFTER COORDINATION WITH WFO SEATTLE...DECIDED CONFIDENCE WAS HIGH
ENOUGH TO WARRANT A GALE WATCH FOR THIS SYSTEM. 12Z ECMWF/GFS SHOW
THIS SYSTEM TAKING A NEAR-IDEAL TRACK AND SPEED FOR DYNAMIC
FETCH...AND THIS SHOWS IN THE WAVE MODELS. ENP GUIDANCE SUGGESTS
A SOLID 17-21 FT SWELL WITH A DOMINANT PERIOD OF 16-20 SECONDS
FOLLOWS THE FRONT...PROBABLY ENOUGH TO WARRANT A HIGH SURF
ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...GALE WATCH FROM THURSDAY MORNING THROUGH THURSDAY EVENING FOR
     COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR WINDS FROM 6 PM THIS EVENING TO
     MIDNIGHT PST TONIGHT FOR WATERS FROM CASCADE HEAD TO
     FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 9 AM TO
     5 PM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPDT 162229
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 PM PST TUE DEC 16 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...PREVIOUS DISCUSSION...18Z TAFS...A WEAK SYSTEM IS
EXITING THE AREA THIS MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT
COUPLE OF HOURS AT KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD
REMAIN DRY THROUGH LATE TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO
THE AREA FROM THE SOUTH AFTER 12Z WITH A MIX OF RAIN AND SNOW
SHOWERS AT KBDN, KRDM, KPSC AND PERHAPS KPDT. MUCH OF THE AREA HAS
IMPROVED TO MVFR/VFR CEILINGS AND VISIBILITIES THOUGH KRDM AND KBDN
WILL CONTINUE TO HAVE LIFR CEILINGS FOR A COUPLE MORE HOURS BEFORE
IMPROVING TO VFR. AFTER 04Z CONDITIONS WILL GENERALLY DROP TO MVFR
LEVELS DUE TO BR AND LIGHT RAIN AND SNOW SHOWERS. WINDS WILL REMAIN
BELOW 12 KTS FOR THE NEXT 24 HOURS. PERRY


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83









000
FXUS66 KPDT 162229
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 PM PST TUE DEC 16 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...PREVIOUS DISCUSSION...18Z TAFS...A WEAK SYSTEM IS
EXITING THE AREA THIS MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT
COUPLE OF HOURS AT KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD
REMAIN DRY THROUGH LATE TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO
THE AREA FROM THE SOUTH AFTER 12Z WITH A MIX OF RAIN AND SNOW
SHOWERS AT KBDN, KRDM, KPSC AND PERHAPS KPDT. MUCH OF THE AREA HAS
IMPROVED TO MVFR/VFR CEILINGS AND VISIBILITIES THOUGH KRDM AND KBDN
WILL CONTINUE TO HAVE LIFR CEILINGS FOR A COUPLE MORE HOURS BEFORE
IMPROVING TO VFR. AFTER 04Z CONDITIONS WILL GENERALLY DROP TO MVFR
LEVELS DUE TO BR AND LIGHT RAIN AND SNOW SHOWERS. WINDS WILL REMAIN
BELOW 12 KTS FOR THE NEXT 24 HOURS. PERRY


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83









000
FXUS66 KPDT 162229
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 PM PST TUE DEC 16 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...PREVIOUS DISCUSSION...18Z TAFS...A WEAK SYSTEM IS
EXITING THE AREA THIS MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT
COUPLE OF HOURS AT KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD
REMAIN DRY THROUGH LATE TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO
THE AREA FROM THE SOUTH AFTER 12Z WITH A MIX OF RAIN AND SNOW
SHOWERS AT KBDN, KRDM, KPSC AND PERHAPS KPDT. MUCH OF THE AREA HAS
IMPROVED TO MVFR/VFR CEILINGS AND VISIBILITIES THOUGH KRDM AND KBDN
WILL CONTINUE TO HAVE LIFR CEILINGS FOR A COUPLE MORE HOURS BEFORE
IMPROVING TO VFR. AFTER 04Z CONDITIONS WILL GENERALLY DROP TO MVFR
LEVELS DUE TO BR AND LIGHT RAIN AND SNOW SHOWERS. WINDS WILL REMAIN
BELOW 12 KTS FOR THE NEXT 24 HOURS. PERRY


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83









000
FXUS66 KPDT 162229
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 PM PST TUE DEC 16 2014

.SHORT TERM...TONIGHT THROUGH FRIDAY...A LITTLE BREAK BETWEEN SYSTEM
THROUGH THIS EVENING THEN THE NEXT WEAK SYSTEM WILL PUSH IN FROM THE
SOUTHWEST OVERNIGHT AND SLOWLY MOVE OVER THE FORECAST AREA
WEDNESDAY. PRECIPITATION AMOUNTS ARE EXPECTED TO BE LIGHT SO
THINKING MINIMAL SNOW ACCUMULATIONS ASSOCIATED WITH IT. THIS SYSTEM
WILL BE EXITING THE FORECAST AREA WEDNESDAY NIGHT AS A TEMPORARY
RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST FOR THURSDAY.
EXPECTING A STRONGER SYSTEM ON FRIDAY THAT WILL BRING RAIN AND SNOW
TO THE FORECAST AREA. SNOW LEVELS WILL BE 2500 TO 4000 FEET MAKING
IT MAINLY A HIGHER ELEVATION SNOW EVENT WITH RAIN IN THE LOWER
ELEVATIONS.

.LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...AN ACTIVE WEATHER
PATTERN WILL CONTINUE THROUGH THE LONG TERM PERIOD. ONE SYSTEM WILL
BE LEAVING THE AREA FRIDAY NIGHT WHILE ANOTHER APPROACHES FROM THE
WEST. THERE WILL BE A CHANCE OF SNOW IN THE MOUNTAINS WHILE THE
LOWER ELEVATIONS WILL BE MOSTLY DRY ASIDE FORM A FEW RAIN SHOWERS IN
THE BLUE MOUNTAIN FOOTHILLS. THE NEXT SYSTEM WILL MOVE ACROSS THE
CASCADES SATURDAY AFTERNOON AND BRING A CHANCE OF RAIN AND MOUNTAIN
SNOW SATURDAY NIGHT BEFORE TAPERING OFF SUNDAY. SNOW LEVELS WILL BE
RISING TO AROUND 6500 FEET ON SUNDAY, SO MAINLY RAIN IS EXPECTED
THEN. PRESSURE GRADIENTS WILL STRENGTHEN AND BREEZY TO WINDY
CONDITIONS WILL BE PRESENT SUNDAY AND SUNDAY NIGHT. BY SUNDAY NIGHT
A NEARLY ZONAL WESTERLY MOIST FLOW WILL BE CROSSING OVER A RIDGE OFF
THE CALIFORNIA COAST. THIS WILL KEEP A CHANCE OF OF RAIN IN THE
MOUNTAINS SUNDAY NIGHT THROUGH TUESDAY WHILE THE LOWER ELEVATIONS
WILL HAVE A CHANCE OF RAIN SUNDAY NIGHT THEN SLOWLY DECREASE TO A
SLIGHT CHANCE OF RAIN MONDAY THROUGH TUESDAY. PERRY


&&

.AVIATION...PREVIOUS DISCUSSION...18Z TAFS...A WEAK SYSTEM IS
EXITING THE AREA THIS MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT
COUPLE OF HOURS AT KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD
REMAIN DRY THROUGH LATE TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO
THE AREA FROM THE SOUTH AFTER 12Z WITH A MIX OF RAIN AND SNOW
SHOWERS AT KBDN, KRDM, KPSC AND PERHAPS KPDT. MUCH OF THE AREA HAS
IMPROVED TO MVFR/VFR CEILINGS AND VISIBILITIES THOUGH KRDM AND KBDN
WILL CONTINUE TO HAVE LIFR CEILINGS FOR A COUPLE MORE HOURS BEFORE
IMPROVING TO VFR. AFTER 04Z CONDITIONS WILL GENERALLY DROP TO MVFR
LEVELS DUE TO BR AND LIGHT RAIN AND SNOW SHOWERS. WINDS WILL REMAIN
BELOW 12 KTS FOR THE NEXT 24 HOURS. PERRY


&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  29  37  32  40 /  10  20  30  10
ALW  29  37  33  40 /  10  20  30  10
PSC  28  38  30  38 /  10  20  20  10
YKM  29  37  28  37 /  10  30  20  10
HRI  28  38  32  40 /  10  20  20  10
ELN  29  37  28  37 /  10  30  20  10
RDM  30  38  24  40 /  20  30  20  10
LGD  30  39  32  39 /  20  20  30  20
GCD  30  40  32  40 /  20  30  30  10
DLS  33  40  34  40 /  10  30  30  10

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83









000
FXUS66 KMFR 162216
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
216 PM PST TUE DEC 16 2014

.DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.AVIATION...BASED ON THE 16/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY ACROSS THE MEDFORD CWA. AREAS OF MVFR CIGS IN
PRECIPITATION WILL DEVELOP THIS AFTERNOON ALONG THE SOUTH COAST
RANGE AND MOST OF SISKIYOU COUNTY WITH HIGHER TERRAIN BECOMING
OBSCURED.  AREAS OF IFR CIGS/VSBYS IN LOW CLOUDS AND FOG WILL
DEVELOP OVER THE WESTERN VALLEYS LATE TONIGHT AND PERSIST THROUGH
MID-MORNING WEDNESDAY.


&&

.MARINE...UPDATED 900 AM PST TUE DEC 16 2014...HEAVY WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF
CAPE BLANCO AND BEYOND 10NM OFFSHORE...WHERE GALE FORCE WINDS ARE
EXPECTED. WINDS WILL DIMINISH AS THE LOW MOVES BY THIS EVENING
THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER FRONT
WILL PUSH THROUGH WITH ANOTHER ROUND OF STRONG SOUTH WINDS...RAIN...
AND STEEP SEAS. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT
PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY.


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     GALE WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.
     HAZARDOUS SEAS WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.

$$




000
FXUS66 KMFR 162216
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
216 PM PST TUE DEC 16 2014

.DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.AVIATION...BASED ON THE 16/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY ACROSS THE MEDFORD CWA. AREAS OF MVFR CIGS IN
PRECIPITATION WILL DEVELOP THIS AFTERNOON ALONG THE SOUTH COAST
RANGE AND MOST OF SISKIYOU COUNTY WITH HIGHER TERRAIN BECOMING
OBSCURED.  AREAS OF IFR CIGS/VSBYS IN LOW CLOUDS AND FOG WILL
DEVELOP OVER THE WESTERN VALLEYS LATE TONIGHT AND PERSIST THROUGH
MID-MORNING WEDNESDAY.


&&

.MARINE...UPDATED 900 AM PST TUE DEC 16 2014...HEAVY WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF
CAPE BLANCO AND BEYOND 10NM OFFSHORE...WHERE GALE FORCE WINDS ARE
EXPECTED. WINDS WILL DIMINISH AS THE LOW MOVES BY THIS EVENING
THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER FRONT
WILL PUSH THROUGH WITH ANOTHER ROUND OF STRONG SOUTH WINDS...RAIN...
AND STEEP SEAS. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT
PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY.


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     GALE WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.
     HAZARDOUS SEAS WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.

$$




000
FXUS66 KMFR 162216
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
216 PM PST TUE DEC 16 2014

.DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.AVIATION...BASED ON THE 16/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY ACROSS THE MEDFORD CWA. AREAS OF MVFR CIGS IN
PRECIPITATION WILL DEVELOP THIS AFTERNOON ALONG THE SOUTH COAST
RANGE AND MOST OF SISKIYOU COUNTY WITH HIGHER TERRAIN BECOMING
OBSCURED.  AREAS OF IFR CIGS/VSBYS IN LOW CLOUDS AND FOG WILL
DEVELOP OVER THE WESTERN VALLEYS LATE TONIGHT AND PERSIST THROUGH
MID-MORNING WEDNESDAY.


&&

.MARINE...UPDATED 900 AM PST TUE DEC 16 2014...HEAVY WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF
CAPE BLANCO AND BEYOND 10NM OFFSHORE...WHERE GALE FORCE WINDS ARE
EXPECTED. WINDS WILL DIMINISH AS THE LOW MOVES BY THIS EVENING
THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER FRONT
WILL PUSH THROUGH WITH ANOTHER ROUND OF STRONG SOUTH WINDS...RAIN...
AND STEEP SEAS. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT
PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY.


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     GALE WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.
     HAZARDOUS SEAS WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.

$$




000
FXUS66 KMFR 162216
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
216 PM PST TUE DEC 16 2014

.DISCUSSION...PRECIPITATION AHEAD OF A SURFACE LOW NEAR 42N/128W IS ALREADY
REACHING CAPETOWN CALIFORNIA AND IS MOVING NORTH TO NORTHEAST. THE
RAP IS DOING FAIRLY WELL IN INITIALIZING THE POSITION OF THE LOW AND
QPF FIELDS THIS AFTERNOON AND HAVE LEANED TOWARDS THIS SOLUTION FOR
THIS EVENING. WINDS HAVE INCREASED AHEAD OF THE LOW IN THE SHASTA
VALLEY AND WILL LAST THROUGH THE NIGHT, BUT DO NOT EXPECT THEM TO
REACH ADVISORY CRITERIA. THE RAP SHOWS THE PRECIP FIELD BREAKING UP
INTO TWO PARTS THIS EVENING. ONE PART WILL MOVE NORTH OVER THE
MARINE WATERS, THE OTHER WILL CONTINUE TO PUSH EAST INTO NORTHERN
CAL AND INTO THE MOUNT SHASTA REGION. THE PARAMETERS ON THE NAM WITH
RESPECT TO SNOW NEAR AND AT MOUNT SHASTA HAVE CHANGED LITTLE FROM
THE PREVIOUS RUN. IT STILL LOOKS FAVORABLE FOR HEAVIER PRECIPITATION
TO DEVELOP LATER THIS EVENING AND TONIGHT DUE TO UPSLOPE FLOW AND
850 MB TEMPERATURES NEAR 0C. IN ADDITION 700MB FLOW IS FROM THE
SOUTH BETWEEN 40-50 KTS. THE MAIN QUESTION WILL BE HOW MUCH. CURRENT
THINKING IS THAT WE`LL HAVE A RAIN WET SNOW MIX TO START THIS
EVENING WITH MODEL SOUNDINGS RIGHT AT THE CUSP BETWEEN RAIN AND
SNOW. PRECIPITATION WILL INCREASE TONIGHT FORCING THE SNOW LEVEL
DOWN LOW ENOUGH TO GET INTO MOUNT SHASTA. SNOW RATIONS WILL BE LOW,
BUT QPF VALUES SUGGEST WE COULD PICK UP AT LEAST 3 INCHES OR MORE
NEAR THE INTERSTATE, ESPECIALLY BETWEEN MOUNT SHASTA AND DUNSMUIR.
IT`S POSSIBLE HIGHWAY 89 COULD GET UP TO 6 INCHES OR MORE BY
DAYBREAK WEDNESDAY.

THE UPPER TROUGH MOVES THROUGH WEDNESDAY MORNING AND THE UPPER FLOW
WILL BECOME WESTERLY WHICH WILL LIMIT THE AMOUNT OF PRECIPITATION
IN THE MOUNT SHASTA REGION. ELSEWHERE VALLEY RAIN AND MOUNTAIN
SNOW SHOWERS WILL LINGER, BUT WERE NOT EXPECTING ANYTHING
NOTEWORTHY WITH MINIMAL IMPACT ON PASSES. SOME LEFTOVER SHOWERS
WILL LINGER INTO WEDNESDAY EVENING, THEN END OVERNIGHT AS
SHORTWAVE RIDGING BUILDS INTO THE AREA. WE`LL CATCH A DRY BREAK ON
THURSDAY WITH THE RIDGE AXIS OVER THE AREA, BUT THIS WILL BE SHORT
LIVED. THE MODELS SHOW A STRONGER FRONT APPROACHING THE AREA
THURSDAY AFTERNOON BRINGING INCREASING SOUTH WINDS OVER THE MARINE
WATERS WHICH COULD GET CLOSE TO GALES.

THIS FRONT WILL PUSH INLAND THURSDAY NIGHT WITH PRECIPITATION
SPREADING OVER MUCH OF THE FORECAST AREA. THE HEAVIEST AMOUNTS WILL
BE ALONG THE COAST RANGE, COASTAL MOUNTAINS AND CASCADES. RIGHT NOW
SNOW LEVELS WILL START OUT HIGH THURSDAY EVENING, BUT WILL DROP
TO AROUND 4500 FEET EARLY FRIDAY MORNING. SO IT`S A GOOD BET THE
MOUNTAIN PASSES WILL GET ACCUMULATING SNOW STARTING LATE THURSDAY
NIGHT THROUGH FRIDAY MORNING. RIGHT NOW, IT LOOKS LIKE CRATER LAKE
COULD PICK UP AT LEAST 6 INCHES OR MORE...A FEW INCHES OVER
SISKIYOU SUMMIT AND HIGHWAY 140. KEEP IN MIND THE DETAILS ON THIS
WILL CHANGE, SO STAY TUNED FOR THE LATEST UPDATES, ESPECIALLY FOR
ANYONE PLANING ON TRAVELING THE WEEKEND BEFORE CHRISTMAS.
-PETRUCELLI

LONG-TERM FORECAST...SATURDAY THROUGH TUESDAY.  A BROAD LONG WAVE
RIDGE WILL BUILD INTO THE WEST COAST SATURDAY AND SUNDAY...WITH
GENERALLY NORTHWEST FLOW ALOFT. SHORT WAVES RIDING OVER THE TOP OF
THE RIDGE WILL WEAKEN IT FROM SUNDAY NIGHT ON...BUT IT WILL REMAIN
IN PLACE THROUGH TUESDAY. THE FLOW ALOFT WILL BECOME MORE ZONAL
THOUGH.

THIS PATTERN WILL FORCE THE MAIN STORM TRACK TO THE NORTH OF THE
MEDFORD CWA...BUT THE AREA WILL STILL CATCH THE SOUTHERN END OF
SEVERAL SYSTEMS WHICH WILL MOVE ONSHORE DURING THIS INTERVAL.  THE
STRONGEST OF THESE SYSTEMS WILL MOVE ONSHORE SATURDAY AFTERNOON AND
EVENING...AND AGAIN MONDAY. THE BULK OF THE ASSOCIATED PRECIPITATION
WILL FALL ALONG THE COAST...COAST RANGE...AND UMPQUA BASIN. AMOUNTS
WILL BE SIGNIFICANT BUT NOT EXCESSIVE...NO FLOODING PROBLEMS ARE
ANTICIPATED. SNOW LEVELS WILL START OFF BETWEEN 4000 AND 5000 FEET
SATURDAY...BUT WILL RISE TO ABOVE 7000 FEET SATURDAY NIGHT INTO
SUNDAY AND REMAIN ABOVE ALL BUT THE HIGHEST TERRAIN UNTIL IT LOWERS
SLIGHTLY TUESDAY NIGHT. SO...THE HEAVIEST SNOWS WILL OCCUR WITH THE
SATURDAY SYSTEM.

&&

.AVIATION...BASED ON THE 16/18Z TAF CYCLE...VFR CONDITIONS WILL
PREVAIL INITIALLY ACROSS THE MEDFORD CWA. AREAS OF MVFR CIGS IN
PRECIPITATION WILL DEVELOP THIS AFTERNOON ALONG THE SOUTH COAST
RANGE AND MOST OF SISKIYOU COUNTY WITH HIGHER TERRAIN BECOMING
OBSCURED.  AREAS OF IFR CIGS/VSBYS IN LOW CLOUDS AND FOG WILL
DEVELOP OVER THE WESTERN VALLEYS LATE TONIGHT AND PERSIST THROUGH
MID-MORNING WEDNESDAY.


&&

.MARINE...UPDATED 900 AM PST TUE DEC 16 2014...HEAVY WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING SEAS...ESPECIALLY SOUTH OF
CAPE BLANCO AND BEYOND 10NM OFFSHORE...WHERE GALE FORCE WINDS ARE
EXPECTED. WINDS WILL DIMINISH AS THE LOW MOVES BY THIS EVENING
THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER FRONT
WILL PUSH THROUGH WITH ANOTHER ROUND OF STRONG SOUTH WINDS...RAIN...
AND STEEP SEAS. VERY HEAVY WEST SWELL AROUND 20 FEET WITH A DOMINANT
PERIOD OF 19 SECONDS WILL ARRIVE ON FRIDAY.


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     GALE WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.
     HAZARDOUS SEAS WARNING UNTIL 7 PM PST THIS EVENING FOR PZZ376.

$$




000
FXUS65 KBOI 162157
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
257 PM MST TUE DEC 16 2014

.SHORT TERM...TONIGHT THROUGH THURSDAY...SHOWERS ARE TAPERING OFF
THIS AFTERNOON AS A SHORTWAVE MOVES OVER THE AREA...AHEAD OF AN
UPPER LOW POSITIONED JUST OFF THE COAST OF CALIFORNIA. THIS UPPER
LOW IS EXPECTED TO CONTINUE TO SLOWLY MOVE EAST...WEAKEN...AND
SPLIT. MOST OF THE AREA WILL SEE A BREAK FROM PRECIP ON WEDNESDAY
WITH SOME CLEARING BETWEEN SYSTEMS. ON THURSDAY...THE NORTHERN
PORTION OF THAT SPLIT TROUGH WILL MOVE OVER THE AREA...BUT WITH
MOST OF THE MOISTURE SQUEEZED OUT BY THE SIERRAS...A CHANCE OF
SNOW IS ONLY IN THE UPSLOPE FAVORED WEST CENTRAL MOUNTAINS. QPF
AND SNOWFALL AMOUNTS ARE LOW FOR THURSDAY.
OTHERWISE...TEMPERATURES WILL BE NEAR NORMAL.

.LONG TERM...THURSDAY NIGHT THROUGH TUESDAY...MODEL AGREEMENT IS
ESPECIALLY GOOD THROUGH TUESDAY. A RIDGE AXIS WILL QUICKLY PASS OVER
THE AREA THURSDAY NIGHT. FAST MOIST FLOW MOVES IN FRIDAY...USHERING
IN A PERIOD OF ABOVE NORMAL TEMPS AND PRECIP. FIRST WAVE HITS
FRIDAY...WITH A STRONGER AND WETTER WAVE SATURDAY NIGHT. POPS HAVE
BEEN INCREASED ACCORDINGLY. WE HAVE RETAINED AN ABOVE NORMAL CHANCE
OF PRECIP ALL THE WAY INTO TUE...DUE TO THE CONTINUATION OF MOIST NW
FLOW ALOFT...EVEN THOUGH THERE IS LESS CONFIDENCE IN THE TIMING OF
INDIVIDUAL WAVES. A KEY COMPONENT OF THIS PATTERN IS A PERSISTENT
UPPER LEVEL HIGH CENTERED NEAR 30N 130W.

&&

.AVIATION...MTNS ARE OBSCURED. MVFR/IFR SNOW SHOWERS AT KTWF/KJER
WILL LINGER INTO THE LATE AFTERNOON. KBNO HAS IFR CIG BUT SNOW HAS
ENDED THERE. PARTIAL CLEARING WILL LEAD TO A CHANCE FOR IFR FOG AT
KBNO...KBKE...AND KMYL LATE TONIGHT. SFC WINDS ARE VARIABLE LESS
THAN 15 KTS...AND WILL BECOME LIGHT AND VARIABLE OVERNIGHT. WINDS
ALOFT WILL REMAIN SE TO SW 10 TO 20 KTS UP TO 10KFT.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...EP
LONG TERM....SP/DD
AVIATION.....SP



000
FXUS66 KPDT 161755 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
955 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

AVIATION...18Z TAFS...A WEAK SYSTEM IS EXITING THE AREA THIS
MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AT
KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD REMAIN DRY THROUGH LATE
TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO THE AREA FROM THE SOUTH
AFTER 12Z WITH A MIX OF RAIN AND SNOW SHOWERS AT KBDN, KRDM, KPSC
AND PERHAPS KPDT. MUCH OF THE AREA HAS IMPROVED TO MVFR/VFR CEILINGS
AND VISIBILITIES THOUGH KRDM AND KBDN WILL CONTINUE TO HAVE LIFR
CEILINGS FOR A COUPLE MORE HOURS BEFORE IMPROVING TO VFR. AFTER 04Z
CONDITIONS WILL GENERALLY DROP TO MVFR LEVELS DUE TO BR AND LIGHT
RAIN AND SNOW SHOWERS. WINDS WILL REMAIN BELOW 12 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83






000
FXUS66 KPDT 161755 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
955 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

AVIATION...18Z TAFS...A WEAK SYSTEM IS EXITING THE AREA THIS
MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AT
KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD REMAIN DRY THROUGH LATE
TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO THE AREA FROM THE SOUTH
AFTER 12Z WITH A MIX OF RAIN AND SNOW SHOWERS AT KBDN, KRDM, KPSC
AND PERHAPS KPDT. MUCH OF THE AREA HAS IMPROVED TO MVFR/VFR CEILINGS
AND VISIBILITIES THOUGH KRDM AND KBDN WILL CONTINUE TO HAVE LIFR
CEILINGS FOR A COUPLE MORE HOURS BEFORE IMPROVING TO VFR. AFTER 04Z
CONDITIONS WILL GENERALLY DROP TO MVFR LEVELS DUE TO BR AND LIGHT
RAIN AND SNOW SHOWERS. WINDS WILL REMAIN BELOW 12 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83






000
FXUS66 KPDT 161755 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
955 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

AVIATION...18Z TAFS...A WEAK SYSTEM IS EXITING THE AREA THIS
MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AT
KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD REMAIN DRY THROUGH LATE
TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO THE AREA FROM THE SOUTH
AFTER 12Z WITH A MIX OF RAIN AND SNOW SHOWERS AT KBDN, KRDM, KPSC
AND PERHAPS KPDT. MUCH OF THE AREA HAS IMPROVED TO MVFR/VFR CEILINGS
AND VISIBILITIES THOUGH KRDM AND KBDN WILL CONTINUE TO HAVE LIFR
CEILINGS FOR A COUPLE MORE HOURS BEFORE IMPROVING TO VFR. AFTER 04Z
CONDITIONS WILL GENERALLY DROP TO MVFR LEVELS DUE TO BR AND LIGHT
RAIN AND SNOW SHOWERS. WINDS WILL REMAIN BELOW 12 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83






000
FXUS66 KPDT 161755 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
955 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

AVIATION...18Z TAFS...A WEAK SYSTEM IS EXITING THE AREA THIS
MORNING. LIGHT RAIN WILL CONTINUE FOR THE NEXT COUPLE OF HOURS AT
KPSC, KALW AND KPDT. OTHER TAF SITES SHOULD REMAIN DRY THROUGH LATE
TONIGHT WHEN ANOTHER WEAK SYSTEM MOVES INTO THE AREA FROM THE SOUTH
AFTER 12Z WITH A MIX OF RAIN AND SNOW SHOWERS AT KBDN, KRDM, KPSC
AND PERHAPS KPDT. MUCH OF THE AREA HAS IMPROVED TO MVFR/VFR CEILINGS
AND VISIBILITIES THOUGH KRDM AND KBDN WILL CONTINUE TO HAVE LIFR
CEILINGS FOR A COUPLE MORE HOURS BEFORE IMPROVING TO VFR. AFTER 04Z
CONDITIONS WILL GENERALLY DROP TO MVFR LEVELS DUE TO BR AND LIGHT
RAIN AND SNOW SHOWERS. WINDS WILL REMAIN BELOW 12 KTS FOR THE NEXT
24 HOURS. PERRY

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83






000
FXUS66 KPQR 161754
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
954 AM PST TUE DEC 16 2014

.SYNOPSIS...SHOWERS WILL DECREASE TODAY AS A WEAK UPPER TROUGH MOVES
NORTHEAST OF THE AREA. AFTER A BRIEF BREAK IN RAIN THIS AFTERNOON AND
EVENING ANOTHER UPPER TROUGH WILL BRING PERIODS OF RAIN...MAINLY TO
THE HIGHER ELEVATIONS TONIGHT AND WEDNESDAY.  A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...AND WIDESPREAD
RAIN THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS AND SUBTROPICAL
MOISTURE SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT
THE HIGHEST PEAKS. COLDER AIR WILL MOVE IN BEHIND THE FRONT WITH SOME
SNOW SHOWERS FOR THE CASCADES PASSES POSSIBLE FRIDAY NIGHT AND
SATURDAY BEFORE ANOTHER WARMER SYSTEM RAISES THE SNOW LEVELS AGAIN
LATE IN THE WEEKEND

&&
.UPDATE...SHOWERS ARE QUICKLY MOVING NORTH OVER NW OREGON AND SW
WASHINGTON THIS MORNING AS A LOW IS SPINNING UP OFFSHORE THE NORTHERN
CALIFORNIA COAST. HAVE REMOVED POPS SOUTH OF SALEM FOR THE REST OF
THIS MORNING AND THE EARLY AFTERNOON...AND HAVE REDUCED POPS NORTH OF
SALEM WITH ISOLATED SHOWERS FOR THE INTERIOR VALLEYS AND SCATTERED
SHOWERS FOR THE HIGHER TERRAIN. SATELLITE AND SURFACE OBSERVATIONS
SHOWS PATCHY FOG IN THE INTERIOR VALLEYS OF SOUTHERN LANE
COUNTY...NEAR EUGENE...AND HAVE ADDED FOG IN THE FORECAST FOR THE
REMAINDER OF THE MORNING.

HAVE CONTINUED THE NORTHWARD TREND OF DISAPPEARING RAIN FOR THIS
AFTERNOON AND EVENING BY REMOVING POPS TO THE NORTH. HOWEVER...THE
POPS AT THIS TIME ARE REINTRODUCED TO THE SOUTH DUE TO THE LOW
SHIFTING INLAND. THE SNOW LEVEL IS AROUND 4000 FT THIS MORNING WITH
WEB CAMS SUGGESTING 1 TO 2 INCHES OF ACCUMULATING SNOW FOR THE CASCADE
PASSES OVERNIGHT.

SATELLITE IMAGERY IS SHOWING CYCLOGENESIS AROUND 200 MILES OFFSHORE OF
THE CALIFORNIA/OREGON BORDER THIS MORNING. THIS LOW MAY BE SLIGHTLY
DEEPER THAN THE PREVIOUS MODELS SUGGESTED AND EXPECT THE EASTERLY
SURFACE PRESSURE GRADIENT TO HANG ON A LITTLE LONGER. THE EASTERLY
WINDS WILL WEAKEN A LITTLE THIS MORNING AND AFTERNOON THAN INCREASE
AGAIN LATE THIS AFTERNOON AND EVENING. THE GRADIENT WILL NOT BE
PARTICULARLY STRONG WITH MODELS FORECASTING A TROUTDALE TO DALLES
GRADIENT AROUND 8 MB...BUT THIS IS STRONGER THAN THE PREVIOUS
FORECAST AND HAVE INCREASED THE EASTERLY WINDS FOR TONIGHT THROUGH
WED MORNING...MAINLY THROUGH THE COLUMBIA RIVER GORGE AND NORTHERN
AREAS. THE DEEPER LOW WILL ALSO RESULT IN A TIGHTER SOUTHERLY
GRADIENT WED AFTERNOON AS THE LOW MOVES INLAND AND HAVE INCREASED THE
SOUTHERLY WINDS FOR THE WILLAMETTE VALLEY A TAD.

THE UPPER TROUGH ASSOCIATED WITH THE FRONT/LOW OFFSHORE IS SPLITTING
AND RAIN FOR TONIGHT AND WEDNESDAY ACROSS NW OREGON AND SW WASHINGTON
IS NOT VERY IMPRESSIVE. MOST OF THE RAIN WILL BE FAR SOUTH OR FAR
NORTH OF US...BUT A PART OF THE UPPER TROUGH WILL APPROACH TONIGHT
AND MOVE OVER WEDNESDAY...MAINTAINING A CHANCE OF SHOWERS. THINK
MOST OF THESE SHOWERS WILL BE OVER THE HIGHER TERRAIN WITH THE
INTERIOR VALLEYS NOT SEEING MUCH RAIN. TJ

.PREVIOUS SHORT TERM...TODAY THROUGH FRIDAY...LIGHT RAIN PERSISTS
TODAY AS A WEAK FRONTAL SYSTEM CONTINUES TO PUSH EAST OF THE FORECAST
AREA EARLY THIS MORNING. SURFACE OBSERVATIONS ARE REPORTING BETWEEN
0.01-0.05" OF RAIN IN THE PAST 6 HOURS...EXCEPT FOR ALMOST 0.10" OF
PRECIP OVER THE COAST RANGE. THE NEXT FRONTAL SYSTEM CAN BE SEEN IN
INFRARED SATELLITE IMAGERY JUST OFF THE OREGON/CALIFORNIA COASTLINE
THIS MORNING. TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER
PORTIONS OF THE HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW
ACCUMULATIONS UP TO AN INCH OR SO ARE POSSIBLE THROUGH THIS MORNING.

EVEN WITH OFFSHORE FLOW PERSISTING...MODELS CONTINUE TO SHOW THE
EASTERLY GRADIENT STARTING TO SLACK OFF TODAY. GRADIENTS FURTHER
WEAKEN THROUGH LATE WED...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE
CASCADES.

MODELS REMAIN CONSISTENT IN SHOWING MUCH OF THE ENERGY ASSOCIATED
WITH THIS NEXT LOW PRES SYSTEM HEADING SOUTH INTO NORTHERN CALIFORNIA
LATER TODAY. AS A RESULT...OFFSHORE LOW LEVEL FLOW BECOMES REINFORCED
WHILE FLOW ALOFT TURNS A BIT MORE SOUTHERLY...ALLOWING SHOWER
ACTIVITY TO DIMINISH BY THIS AFTERNOON. SHOWERS MAY LINGER LONGER
ALONG THE CENTRAL OREGON COAST THOUGH. MOISTURE BEGINS TO SPREAD
ACROSS THE AREA AS THE CENTER OF THE LOW PRES DRIFTS TOWARDS THE
OREGON/CALIFORNIA BORDER OVERNIGHT TONIGHT INTO WEDNESDAY MORNING.
THE UPPER LEVEL TROUGH AXIS MOVES INLAND MIDDAY WEDNESDAY AND
WEDNESDAY NIGHT... WHICH SHOULD BRING ANOTHER ROUND OF PRECIP TO THE
AREA. BRIEF UPPER LEVEL RIDGING DEVELOPS FOR THURSDAY...BUT A WARM
FRONT AHEAD OF THE NEXT ORGANIZED FRONTAL BAND COULD BRING A THREAT
FOR PRECIP BY EARLY THURSDAY AFTERNOON. EAST WINDS MAY PICK UP AGAIN
THROUGH THE GORGE AS THIS SYSTEM APPROACHES THE COAST. THIS STRONG
FRONTAL SYSTEM PUSHES INTO THE PACIFIC NORTHWEST FRIDAY...BRINGING A
DECENT BATCH OF PRECIP TO THE AREA AS WELL AS GUSTY SOUTH WINDS FOR
THE COAST.

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY NIGHT
THROUGH MONDAY...A COLD AIR UNSTABLE AIRMASS WILL FOLLOW A STRONG
FRONTAL SYSTEM AND KEEP SHOWERS GOING INTO FRIDAY NIGHT. SNOW LEVELS
SHOULD LOWER TO NEAR 4000 FT ON SO ACCUMULATING SNOW APPEARS LIKELY
FOR AT LEAST THE HIGHER PASSES. AN ADDITIONAL SHORTWAVE TROUGH OR TWO
COULD ENHANCE SHOWER ACTIVITY EARLY IN THE WEEKEND AND BRING MUCH
NEEDED SNOW TO THE HIGHER CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...MAINLY VFR CONDITIONS TODAY IN LIGHT TO MODERATE
OFFSHORE FLOW ACROSS FORECAST AREA. A FEW EXCEPTIONS THIS
MORNING...SOME LINGERING MVFR NEAR KAST AND SOME FOG IN THE
WILLAMETTE VALLEY SOUTH OF KCVO. ALSO EASTERLY UPSLOPE FLOW
CAUSING MOUNTAIN OBSCURATIONS ALONG THE EAST SLOPES AND CREST OF
THE CASCADES.

THE MVFR CIGS NEAR KAST SHOULD LIFT AS THE FRONTAL ZONE WHICH
BROUGHT -RA EARLY THIS MORNING CONTINUES TO DRIFT NORTH INTO
WASHINGTON. AS FOR THE LIFR/VLIFR CONDITIONS AROUND KEUG... THEY
WILL PROBABLY BE MORE STUBBORN AS LOW PRESSURE OFF THE NORTHERN CA
COAST CONTINUES TO PULL IN LIGHT N-NE FLOW...JAMMING LOW CLOUDS
AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. SUSPECT IT WILL
LIFT TO REGULAR IFR WITH CIGS ABOVE 500 FT BY MIDDAY...BUT WILL
PROBABLY DROP BACK DOWN TO NEAR THE DECK LATER TONIGHT AS -RA
REDEVELOPS WITH OUR NEXT FRONTAL SYSTEM.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS BETWEEN 4K TO 6K
FT THIS MORNING RISING TO AROUND 12K FT THIS AFTERNOON. LIGHT TO
MODERATE EAST SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...SATELLITE IMAGERY THIS MORNING SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 200 NM WEST OF CRESCENT CITY CA. THIS
SYSTEM APPEARS TO HAVE STRENGTHENED TO AROUND 995 MB BASED ON
SATELLITE ANALYSIS AND THE MAGNITUDE OF WINDS ASSOCIATED WITH THE
LOW. MODELS APPEAR TO BE INITIALIZING THIS LOW TOO WEAKLY...EVEN
THE 16Z RAP ONLY SHOWS A 1000 MB LOW IN THIS LOCATION. RAPIDSCAT
IMAGERY FROM ABOARD THE INTERNATIONAL SPACE STATION SHOWS
SATELLITE-DERIVED WINDS OF UP TO 40 KT IN SE QUADRANT OF THIS
LOW...AND BUOY 46002 IS GUSTING TO GALE FORCE IN THE NW QUADRANT
OF THE LOW. THIS SYSTEM WILL NEED TO BE WATCHED CLOSELY AS IT
DRIFTS NE TOWARD OREGON THE NEXT 24-36 HRS. HOWEVER IT APPEARS THE
LOW IS APPROACHING ITS MAXIMUM STRENGTH AND WILL LIKELY START
WEAKENING AS MODELS SUGGEST BY TONIGHT. THEREFORE WE DID NOT
DEVIATE TOO FAR FROM THE MODELS WITH OUR WIND/SWELL FORECAST IN
THE NEXT 1-2 DAYS.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 150W-160W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
ENP GUIDANCE SUGGESTS A SOLID 16-20 FT SWELL WITH A DOMINANT
PERIOD OF 16-20 SECONDS FOLLOWS THE FRONT...POSSIBLY ENOUGH TO
WARRANT A HIGH SURF ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PST TODAY FOR WATERS
     FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM-
     WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL NOON PST TODAY
     FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 10 NM-
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 2 PM
     PST THIS AFTERNOON.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 161754
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
954 AM PST TUE DEC 16 2014

.SYNOPSIS...SHOWERS WILL DECREASE TODAY AS A WEAK UPPER TROUGH MOVES
NORTHEAST OF THE AREA. AFTER A BRIEF BREAK IN RAIN THIS AFTERNOON AND
EVENING ANOTHER UPPER TROUGH WILL BRING PERIODS OF RAIN...MAINLY TO
THE HIGHER ELEVATIONS TONIGHT AND WEDNESDAY.  A MORE ORGANIZED FRONT
WILL BRING GUSTY WINDS AND LARGE SURF TO THE COAST...AND WIDESPREAD
RAIN THURSDAY NIGHT AND FRIDAY. RISING SNOW LEVELS AND SUBTROPICAL
MOISTURE SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT
THE HIGHEST PEAKS. COLDER AIR WILL MOVE IN BEHIND THE FRONT WITH SOME
SNOW SHOWERS FOR THE CASCADES PASSES POSSIBLE FRIDAY NIGHT AND
SATURDAY BEFORE ANOTHER WARMER SYSTEM RAISES THE SNOW LEVELS AGAIN
LATE IN THE WEEKEND

&&
.UPDATE...SHOWERS ARE QUICKLY MOVING NORTH OVER NW OREGON AND SW
WASHINGTON THIS MORNING AS A LOW IS SPINNING UP OFFSHORE THE NORTHERN
CALIFORNIA COAST. HAVE REMOVED POPS SOUTH OF SALEM FOR THE REST OF
THIS MORNING AND THE EARLY AFTERNOON...AND HAVE REDUCED POPS NORTH OF
SALEM WITH ISOLATED SHOWERS FOR THE INTERIOR VALLEYS AND SCATTERED
SHOWERS FOR THE HIGHER TERRAIN. SATELLITE AND SURFACE OBSERVATIONS
SHOWS PATCHY FOG IN THE INTERIOR VALLEYS OF SOUTHERN LANE
COUNTY...NEAR EUGENE...AND HAVE ADDED FOG IN THE FORECAST FOR THE
REMAINDER OF THE MORNING.

HAVE CONTINUED THE NORTHWARD TREND OF DISAPPEARING RAIN FOR THIS
AFTERNOON AND EVENING BY REMOVING POPS TO THE NORTH. HOWEVER...THE
POPS AT THIS TIME ARE REINTRODUCED TO THE SOUTH DUE TO THE LOW
SHIFTING INLAND. THE SNOW LEVEL IS AROUND 4000 FT THIS MORNING WITH
WEB CAMS SUGGESTING 1 TO 2 INCHES OF ACCUMULATING SNOW FOR THE CASCADE
PASSES OVERNIGHT.

SATELLITE IMAGERY IS SHOWING CYCLOGENESIS AROUND 200 MILES OFFSHORE OF
THE CALIFORNIA/OREGON BORDER THIS MORNING. THIS LOW MAY BE SLIGHTLY
DEEPER THAN THE PREVIOUS MODELS SUGGESTED AND EXPECT THE EASTERLY
SURFACE PRESSURE GRADIENT TO HANG ON A LITTLE LONGER. THE EASTERLY
WINDS WILL WEAKEN A LITTLE THIS MORNING AND AFTERNOON THAN INCREASE
AGAIN LATE THIS AFTERNOON AND EVENING. THE GRADIENT WILL NOT BE
PARTICULARLY STRONG WITH MODELS FORECASTING A TROUTDALE TO DALLES
GRADIENT AROUND 8 MB...BUT THIS IS STRONGER THAN THE PREVIOUS
FORECAST AND HAVE INCREASED THE EASTERLY WINDS FOR TONIGHT THROUGH
WED MORNING...MAINLY THROUGH THE COLUMBIA RIVER GORGE AND NORTHERN
AREAS. THE DEEPER LOW WILL ALSO RESULT IN A TIGHTER SOUTHERLY
GRADIENT WED AFTERNOON AS THE LOW MOVES INLAND AND HAVE INCREASED THE
SOUTHERLY WINDS FOR THE WILLAMETTE VALLEY A TAD.

THE UPPER TROUGH ASSOCIATED WITH THE FRONT/LOW OFFSHORE IS SPLITTING
AND RAIN FOR TONIGHT AND WEDNESDAY ACROSS NW OREGON AND SW WASHINGTON
IS NOT VERY IMPRESSIVE. MOST OF THE RAIN WILL BE FAR SOUTH OR FAR
NORTH OF US...BUT A PART OF THE UPPER TROUGH WILL APPROACH TONIGHT
AND MOVE OVER WEDNESDAY...MAINTAINING A CHANCE OF SHOWERS. THINK
MOST OF THESE SHOWERS WILL BE OVER THE HIGHER TERRAIN WITH THE
INTERIOR VALLEYS NOT SEEING MUCH RAIN. TJ

.PREVIOUS SHORT TERM...TODAY THROUGH FRIDAY...LIGHT RAIN PERSISTS
TODAY AS A WEAK FRONTAL SYSTEM CONTINUES TO PUSH EAST OF THE FORECAST
AREA EARLY THIS MORNING. SURFACE OBSERVATIONS ARE REPORTING BETWEEN
0.01-0.05" OF RAIN IN THE PAST 6 HOURS...EXCEPT FOR ALMOST 0.10" OF
PRECIP OVER THE COAST RANGE. THE NEXT FRONTAL SYSTEM CAN BE SEEN IN
INFRARED SATELLITE IMAGERY JUST OFF THE OREGON/CALIFORNIA COASTLINE
THIS MORNING. TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER
PORTIONS OF THE HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW
ACCUMULATIONS UP TO AN INCH OR SO ARE POSSIBLE THROUGH THIS MORNING.

EVEN WITH OFFSHORE FLOW PERSISTING...MODELS CONTINUE TO SHOW THE
EASTERLY GRADIENT STARTING TO SLACK OFF TODAY. GRADIENTS FURTHER
WEAKEN THROUGH LATE WED...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE
CASCADES.

MODELS REMAIN CONSISTENT IN SHOWING MUCH OF THE ENERGY ASSOCIATED
WITH THIS NEXT LOW PRES SYSTEM HEADING SOUTH INTO NORTHERN CALIFORNIA
LATER TODAY. AS A RESULT...OFFSHORE LOW LEVEL FLOW BECOMES REINFORCED
WHILE FLOW ALOFT TURNS A BIT MORE SOUTHERLY...ALLOWING SHOWER
ACTIVITY TO DIMINISH BY THIS AFTERNOON. SHOWERS MAY LINGER LONGER
ALONG THE CENTRAL OREGON COAST THOUGH. MOISTURE BEGINS TO SPREAD
ACROSS THE AREA AS THE CENTER OF THE LOW PRES DRIFTS TOWARDS THE
OREGON/CALIFORNIA BORDER OVERNIGHT TONIGHT INTO WEDNESDAY MORNING.
THE UPPER LEVEL TROUGH AXIS MOVES INLAND MIDDAY WEDNESDAY AND
WEDNESDAY NIGHT... WHICH SHOULD BRING ANOTHER ROUND OF PRECIP TO THE
AREA. BRIEF UPPER LEVEL RIDGING DEVELOPS FOR THURSDAY...BUT A WARM
FRONT AHEAD OF THE NEXT ORGANIZED FRONTAL BAND COULD BRING A THREAT
FOR PRECIP BY EARLY THURSDAY AFTERNOON. EAST WINDS MAY PICK UP AGAIN
THROUGH THE GORGE AS THIS SYSTEM APPROACHES THE COAST. THIS STRONG
FRONTAL SYSTEM PUSHES INTO THE PACIFIC NORTHWEST FRIDAY...BRINGING A
DECENT BATCH OF PRECIP TO THE AREA AS WELL AS GUSTY SOUTH WINDS FOR
THE COAST.

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY NIGHT
THROUGH MONDAY...A COLD AIR UNSTABLE AIRMASS WILL FOLLOW A STRONG
FRONTAL SYSTEM AND KEEP SHOWERS GOING INTO FRIDAY NIGHT. SNOW LEVELS
SHOULD LOWER TO NEAR 4000 FT ON SO ACCUMULATING SNOW APPEARS LIKELY
FOR AT LEAST THE HIGHER PASSES. AN ADDITIONAL SHORTWAVE TROUGH OR TWO
COULD ENHANCE SHOWER ACTIVITY EARLY IN THE WEEKEND AND BRING MUCH
NEEDED SNOW TO THE HIGHER CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...MAINLY VFR CONDITIONS TODAY IN LIGHT TO MODERATE
OFFSHORE FLOW ACROSS FORECAST AREA. A FEW EXCEPTIONS THIS
MORNING...SOME LINGERING MVFR NEAR KAST AND SOME FOG IN THE
WILLAMETTE VALLEY SOUTH OF KCVO. ALSO EASTERLY UPSLOPE FLOW
CAUSING MOUNTAIN OBSCURATIONS ALONG THE EAST SLOPES AND CREST OF
THE CASCADES.

THE MVFR CIGS NEAR KAST SHOULD LIFT AS THE FRONTAL ZONE WHICH
BROUGHT -RA EARLY THIS MORNING CONTINUES TO DRIFT NORTH INTO
WASHINGTON. AS FOR THE LIFR/VLIFR CONDITIONS AROUND KEUG... THEY
WILL PROBABLY BE MORE STUBBORN AS LOW PRESSURE OFF THE NORTHERN CA
COAST CONTINUES TO PULL IN LIGHT N-NE FLOW...JAMMING LOW CLOUDS
AGAINST THE SOUTH END OF THE WILLAMETTE VALLEY. SUSPECT IT WILL
LIFT TO REGULAR IFR WITH CIGS ABOVE 500 FT BY MIDDAY...BUT WILL
PROBABLY DROP BACK DOWN TO NEAR THE DECK LATER TONIGHT AS -RA
REDEVELOPS WITH OUR NEXT FRONTAL SYSTEM.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS BETWEEN 4K TO 6K
FT THIS MORNING RISING TO AROUND 12K FT THIS AFTERNOON. LIGHT TO
MODERATE EAST SFC WINDS THROUGH THIS EVENING.  WEAGLE

&&

.MARINE...SATELLITE IMAGERY THIS MORNING SHOWS A WELL-DEFINED LOW
PRESSURE SYSTEM ABOUT 200 NM WEST OF CRESCENT CITY CA. THIS
SYSTEM APPEARS TO HAVE STRENGTHENED TO AROUND 995 MB BASED ON
SATELLITE ANALYSIS AND THE MAGNITUDE OF WINDS ASSOCIATED WITH THE
LOW. MODELS APPEAR TO BE INITIALIZING THIS LOW TOO WEAKLY...EVEN
THE 16Z RAP ONLY SHOWS A 1000 MB LOW IN THIS LOCATION. RAPIDSCAT
IMAGERY FROM ABOARD THE INTERNATIONAL SPACE STATION SHOWS
SATELLITE-DERIVED WINDS OF UP TO 40 KT IN SE QUADRANT OF THIS
LOW...AND BUOY 46002 IS GUSTING TO GALE FORCE IN THE NW QUADRANT
OF THE LOW. THIS SYSTEM WILL NEED TO BE WATCHED CLOSELY AS IT
DRIFTS NE TOWARD OREGON THE NEXT 24-36 HRS. HOWEVER IT APPEARS THE
LOW IS APPROACHING ITS MAXIMUM STRENGTH AND WILL LIKELY START
WEAKENING AS MODELS SUGGEST BY TONIGHT. THEREFORE WE DID NOT
DEVIATE TOO FAR FROM THE MODELS WITH OUR WIND/SWELL FORECAST IN
THE NEXT 1-2 DAYS.

THE NEXT RELATIVELY STRONG FRONTAL SYSTEM IS BEGINNING TO TAKE
SHAPE BETWEEN 150W-160W...AND MAY PRODUCE GALES FOR OUR WATERS AS
IT MOVES ONSHORE LATER THU/EARLY FRI. THERE IS A GOOD POTENTIAL
FOR COASTAL JET FORMATION WHICH WOULD ENHANCE WINDS JUST AHEAD OF
THE FRONT WITH GUSTS TO 45 KT POSSIBLE NEAR THE COAST THU NIGHT.
ENP GUIDANCE SUGGESTS A SOLID 16-20 FT SWELL WITH A DOMINANT
PERIOD OF 16-20 SECONDS FOLLOWS THE FRONT...POSSIBLY ENOUGH TO
WARRANT A HIGH SURF ADVISORY FRIDAY.  WEAGLE

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PST TODAY FOR WATERS
     FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM-
     WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL NOON PST TODAY
     FOR COASTAL WATERS FROM CASCADE HEAD TO FLORENCE OR OUT 10 NM-
     WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10
     TO 60 NM-WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO
     60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 2 PM
     PST THIS AFTERNOON.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 11 PM
     THIS EVENING TO 3 AM PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KMFR 161723
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
923 AM PST TUE DEC 16 2014

.DISCUSSION...THE WEAK TROUGH IS NOW MOVING EAST AND VERY WEAK
RIDGE IS BUILDING OVER THE AREA. THIS WILL GIVE US A RELATIVE
BREAK IN THE WEATHER FOR MOST OF THE DAY. ANY PRECIPITATION
THROUGH THIS AFTERNOON WILL BE ISOLATED. HOWEVER I DID KEEP HIGHER
POPS IN SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY AS A SURFACE
LOW NEAR 41W/128W MOVES EAST SOUTHEAST AND PRECIPITATION AHEAD OF
IT COULD MOVE IN THOSE AREAS LATE THIS AFTERNOON. SPEAKING OF THE
SURFACE LOW, THE 12Z MODELS SHOW THE LOW SPINNING UP AS IT MOVES
EAST AND THIS IS ALREADY EVIDENT IN THE WATER VAPOR IMAGE AND WILL
BRING GUSTY WINDS ALONG THE SOUTH COAST AND MARINE WATERS. IN FACT
WINDS COULD REACH LOW END GALES OVER THE OUTER WATERS FOR ABOUT 6
HOURS, THUS A GALE WARNING HAS BEEN ISSUED.

THE MODELS SHOW THE BULK OF THE MOISTURE MOVING INTO NORTHERN CAL
TONIGHT INTO TUESDAY WITH THE NECESSARY INGREDIENTS NEEDED FOR
ACCUMULATING SNOW NEAR AND IN MOUNT SHASTA. AS MENTIONED IN THE
PREVIOUS DISCUSSION, SNOW RATIONS WILL BE LOW WHICH WILL LIMIT THE
AMOUNT OF ACCUMULATING SNOW, BUT STILL ENOUGH TO CAUSE TRAVEL
CONCERNS ALONG I-5 NEAR DUNSMUIR AND HIGHWAY 89. -PETRUCELLI.



&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE... A DISORGANIZED FRONTAL
SYSTEM WILL CONTINUE TO PUSH SHOWERS ACROSS THE AREA THIS MORNING
PARTIALLY OBSCURING THE MOUNTAINS. IN THE VALLEYS MOSTLY VFR
CONDITIONS PREVAIL, WITH SOME MVFR ALONG VALLEY EDGES AND LOCAL LIFR
FOG. LOW PRESSURE APPROACHING FROM THE SOUTHWEST WILL RESULT IN EAST
WINDS ACROSS THE AREA TONIGHT THROUGH WEDNESDAY MORNING. THIS WILL
RESULT IN A DECREASE IN SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST
AND AWAY FROM THE COAST INCREASING THE CHANCE OF IFR TO LIFR LOW
CLOUDS AND FOG THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE
ORGANIZED PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL


&&

.MARINE....UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS AND LOW
END GALES OVER THE OUTER WATERS, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL


&&

.PREV DISCUSSION... /ISSUED 546 AM PST TUE DEC 16 2014/

SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     HAZARDOUS SEAS WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS
     EVENING FOR PZZ376.
     GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS EVENING
     FOR PZZ376.

$$




000
FXUS66 KMFR 161723
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
923 AM PST TUE DEC 16 2014

.DISCUSSION...THE WEAK TROUGH IS NOW MOVING EAST AND VERY WEAK
RIDGE IS BUILDING OVER THE AREA. THIS WILL GIVE US A RELATIVE
BREAK IN THE WEATHER FOR MOST OF THE DAY. ANY PRECIPITATION
THROUGH THIS AFTERNOON WILL BE ISOLATED. HOWEVER I DID KEEP HIGHER
POPS IN SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY AS A SURFACE
LOW NEAR 41W/128W MOVES EAST SOUTHEAST AND PRECIPITATION AHEAD OF
IT COULD MOVE IN THOSE AREAS LATE THIS AFTERNOON. SPEAKING OF THE
SURFACE LOW, THE 12Z MODELS SHOW THE LOW SPINNING UP AS IT MOVES
EAST AND THIS IS ALREADY EVIDENT IN THE WATER VAPOR IMAGE AND WILL
BRING GUSTY WINDS ALONG THE SOUTH COAST AND MARINE WATERS. IN FACT
WINDS COULD REACH LOW END GALES OVER THE OUTER WATERS FOR ABOUT 6
HOURS, THUS A GALE WARNING HAS BEEN ISSUED.

THE MODELS SHOW THE BULK OF THE MOISTURE MOVING INTO NORTHERN CAL
TONIGHT INTO TUESDAY WITH THE NECESSARY INGREDIENTS NEEDED FOR
ACCUMULATING SNOW NEAR AND IN MOUNT SHASTA. AS MENTIONED IN THE
PREVIOUS DISCUSSION, SNOW RATIONS WILL BE LOW WHICH WILL LIMIT THE
AMOUNT OF ACCUMULATING SNOW, BUT STILL ENOUGH TO CAUSE TRAVEL
CONCERNS ALONG I-5 NEAR DUNSMUIR AND HIGHWAY 89. -PETRUCELLI.



&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE... A DISORGANIZED FRONTAL
SYSTEM WILL CONTINUE TO PUSH SHOWERS ACROSS THE AREA THIS MORNING
PARTIALLY OBSCURING THE MOUNTAINS. IN THE VALLEYS MOSTLY VFR
CONDITIONS PREVAIL, WITH SOME MVFR ALONG VALLEY EDGES AND LOCAL LIFR
FOG. LOW PRESSURE APPROACHING FROM THE SOUTHWEST WILL RESULT IN EAST
WINDS ACROSS THE AREA TONIGHT THROUGH WEDNESDAY MORNING. THIS WILL
RESULT IN A DECREASE IN SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST
AND AWAY FROM THE COAST INCREASING THE CHANCE OF IFR TO LIFR LOW
CLOUDS AND FOG THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE
ORGANIZED PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL


&&

.MARINE....UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS AND LOW
END GALES OVER THE OUTER WATERS, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL


&&

.PREV DISCUSSION... /ISSUED 546 AM PST TUE DEC 16 2014/

SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     HAZARDOUS SEAS WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS
     EVENING FOR PZZ376.
     GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS EVENING
     FOR PZZ376.

$$




000
FXUS66 KMFR 161723
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
923 AM PST TUE DEC 16 2014

.DISCUSSION...THE WEAK TROUGH IS NOW MOVING EAST AND VERY WEAK
RIDGE IS BUILDING OVER THE AREA. THIS WILL GIVE US A RELATIVE
BREAK IN THE WEATHER FOR MOST OF THE DAY. ANY PRECIPITATION
THROUGH THIS AFTERNOON WILL BE ISOLATED. HOWEVER I DID KEEP HIGHER
POPS IN SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY AS A SURFACE
LOW NEAR 41W/128W MOVES EAST SOUTHEAST AND PRECIPITATION AHEAD OF
IT COULD MOVE IN THOSE AREAS LATE THIS AFTERNOON. SPEAKING OF THE
SURFACE LOW, THE 12Z MODELS SHOW THE LOW SPINNING UP AS IT MOVES
EAST AND THIS IS ALREADY EVIDENT IN THE WATER VAPOR IMAGE AND WILL
BRING GUSTY WINDS ALONG THE SOUTH COAST AND MARINE WATERS. IN FACT
WINDS COULD REACH LOW END GALES OVER THE OUTER WATERS FOR ABOUT 6
HOURS, THUS A GALE WARNING HAS BEEN ISSUED.

THE MODELS SHOW THE BULK OF THE MOISTURE MOVING INTO NORTHERN CAL
TONIGHT INTO TUESDAY WITH THE NECESSARY INGREDIENTS NEEDED FOR
ACCUMULATING SNOW NEAR AND IN MOUNT SHASTA. AS MENTIONED IN THE
PREVIOUS DISCUSSION, SNOW RATIONS WILL BE LOW WHICH WILL LIMIT THE
AMOUNT OF ACCUMULATING SNOW, BUT STILL ENOUGH TO CAUSE TRAVEL
CONCERNS ALONG I-5 NEAR DUNSMUIR AND HIGHWAY 89. -PETRUCELLI.



&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE... A DISORGANIZED FRONTAL
SYSTEM WILL CONTINUE TO PUSH SHOWERS ACROSS THE AREA THIS MORNING
PARTIALLY OBSCURING THE MOUNTAINS. IN THE VALLEYS MOSTLY VFR
CONDITIONS PREVAIL, WITH SOME MVFR ALONG VALLEY EDGES AND LOCAL LIFR
FOG. LOW PRESSURE APPROACHING FROM THE SOUTHWEST WILL RESULT IN EAST
WINDS ACROSS THE AREA TONIGHT THROUGH WEDNESDAY MORNING. THIS WILL
RESULT IN A DECREASE IN SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST
AND AWAY FROM THE COAST INCREASING THE CHANCE OF IFR TO LIFR LOW
CLOUDS AND FOG THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE
ORGANIZED PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL


&&

.MARINE....UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS AND LOW
END GALES OVER THE OUTER WATERS, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL


&&

.PREV DISCUSSION... /ISSUED 546 AM PST TUE DEC 16 2014/

SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     HAZARDOUS SEAS WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS
     EVENING FOR PZZ376.
     GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS EVENING
     FOR PZZ376.

$$




000
FXUS66 KMFR 161723
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
923 AM PST TUE DEC 16 2014

.DISCUSSION...THE WEAK TROUGH IS NOW MOVING EAST AND VERY WEAK
RIDGE IS BUILDING OVER THE AREA. THIS WILL GIVE US A RELATIVE
BREAK IN THE WEATHER FOR MOST OF THE DAY. ANY PRECIPITATION
THROUGH THIS AFTERNOON WILL BE ISOLATED. HOWEVER I DID KEEP HIGHER
POPS IN SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY AS A SURFACE
LOW NEAR 41W/128W MOVES EAST SOUTHEAST AND PRECIPITATION AHEAD OF
IT COULD MOVE IN THOSE AREAS LATE THIS AFTERNOON. SPEAKING OF THE
SURFACE LOW, THE 12Z MODELS SHOW THE LOW SPINNING UP AS IT MOVES
EAST AND THIS IS ALREADY EVIDENT IN THE WATER VAPOR IMAGE AND WILL
BRING GUSTY WINDS ALONG THE SOUTH COAST AND MARINE WATERS. IN FACT
WINDS COULD REACH LOW END GALES OVER THE OUTER WATERS FOR ABOUT 6
HOURS, THUS A GALE WARNING HAS BEEN ISSUED.

THE MODELS SHOW THE BULK OF THE MOISTURE MOVING INTO NORTHERN CAL
TONIGHT INTO TUESDAY WITH THE NECESSARY INGREDIENTS NEEDED FOR
ACCUMULATING SNOW NEAR AND IN MOUNT SHASTA. AS MENTIONED IN THE
PREVIOUS DISCUSSION, SNOW RATIONS WILL BE LOW WHICH WILL LIMIT THE
AMOUNT OF ACCUMULATING SNOW, BUT STILL ENOUGH TO CAUSE TRAVEL
CONCERNS ALONG I-5 NEAR DUNSMUIR AND HIGHWAY 89. -PETRUCELLI.



&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE... A DISORGANIZED FRONTAL
SYSTEM WILL CONTINUE TO PUSH SHOWERS ACROSS THE AREA THIS MORNING
PARTIALLY OBSCURING THE MOUNTAINS. IN THE VALLEYS MOSTLY VFR
CONDITIONS PREVAIL, WITH SOME MVFR ALONG VALLEY EDGES AND LOCAL LIFR
FOG. LOW PRESSURE APPROACHING FROM THE SOUTHWEST WILL RESULT IN EAST
WINDS ACROSS THE AREA TONIGHT THROUGH WEDNESDAY MORNING. THIS WILL
RESULT IN A DECREASE IN SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST
AND AWAY FROM THE COAST INCREASING THE CHANCE OF IFR TO LIFR LOW
CLOUDS AND FOG THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE
ORGANIZED PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL


&&

.MARINE....UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS AND LOW
END GALES OVER THE OUTER WATERS, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL


&&

.PREV DISCUSSION... /ISSUED 546 AM PST TUE DEC 16 2014/

SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 1 AM PST WEDNESDAY FOR
     PZZ356-370.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST WEDNESDAY
     FOR PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 AM PST WEDNESDAY FOR
     PZZ376.
     HAZARDOUS SEAS WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS
     EVENING FOR PZZ376.
     GALE WARNING FROM 1 PM THIS AFTERNOON TO 7 PM PST THIS EVENING
     FOR PZZ376.

$$




000
FXUS66 KPDT 161641
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
840 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83








000
FXUS66 KPDT 161641
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
840 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH WEDNESDAY...A WEAK WEATEHR SYSTEM
IS PASSING OVER THE AREA TODAY FROM SOUTH TO NORTH. IT HAS BROUGHT
SOME LIGHT SNOW AND RAIN TO THE REGION. MAIN PRECIPITATION THIS
MORNING WILL BE OVER THE NORTHERN PORTION OF THE FORECAST AREA THEN
TAPER OFF TO SOME SHOWERS BY AFTERNOON THEN ENDING BY EVENING AS IT
MOVES OFF TO THE NORTH. SOUTHERN PORTION OF THE FORECAST AREA WILL
SEE SOME DECREASING SHOWERS THIS MORNING THE COMING TO AN BY
AFTERNOON. ANOTHER WEAK SYSTEM WILL SPREAD MOISTURE AND PRECIPITATION
INTO CENTRAL OREGON LATE TONIGHT THEN ACROSS THE REST OF THE
FORECAST AREA ON WEDNESDAY. THIS SYSTEM WILL ALSO PRODUCE LIGHT
PRECIPITATION AMOUNTS SO SNOW ACCUMULATIONS ARE NOT EXPECTED TO BE
SIGNIFICANT.

&&

.PREV DISC... /ISSUED 328 AM PST TUE DEC 16 2014/

SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  34  29  38  31 /  60  10  30  30
ALW  36  29  39  32 /  60  10  20  30
PSC  39  28  38  31 /  60  10  30  30
YKM  37  29  37  28 /  60  10  30  30
HRI  39  28  38  31 /  60  10  30  30
ELN  36  29  37  27 /  60  10  30  30
RDM  37  30  40  26 /  40  20  30  30
LGD  38  30  39  29 /  60  20  30  30
GCD  39  30  39  28 /  50  20  30  30
DLS  41  33  41  32 /  60  10  40  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

91/83/83









000
FXUS65 KBOI 161620
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
920 AM MST TUE DEC 16 2014

.DISCUSSION...SNOW AND RAIN SHOWERS ARE CONTINUING THIS MORNING AS
AN UPPER LOW IS STILL WORKING ITS WAY ACROSS COASTAL
CALIFORNIA...BRINGING MOISTURE TO OUR AREA. THESE SHOWERS ARE
STILL EXPECTED TO TAPER OFF AS TODAY PROGRESSES WITH LITTLE
ACCUMULATION.

&&

.AVIATION...MTNS OBSCURED. LIGHT SNOW IS WIDESPREAD OVER THE HIGHER
TERRAIN AND ALSO IN THE WESTERN MAGIC VALLEY THIS MORNING...BUT WILL
DECREASE IN COVERAGE THIS AFTERNOON AND EVENING. SNOW LEVEL IS
AROUND 4000 FT. SURFACE WIND THROUGH TONIGHT WILL BE SOUTH OR
SOUTHEAST LESS THAN 10 KTS...EXCEPT KJER WHERE NE WINDS ARE 10-20
KTS. WINDS ALOFT... THROUGH 10 KFT MSL...WILL BE SE TO SW 15 TO 25
KTS TODAY AND TONIGHT.

&&

.PREV DISCUSSION...
SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...EP
AVIATION.....SP
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 161620
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
920 AM MST TUE DEC 16 2014

.DISCUSSION...SNOW AND RAIN SHOWERS ARE CONTINUING THIS MORNING AS
AN UPPER LOW IS STILL WORKING ITS WAY ACROSS COASTAL
CALIFORNIA...BRINGING MOISTURE TO OUR AREA. THESE SHOWERS ARE
STILL EXPECTED TO TAPER OFF AS TODAY PROGRESSES WITH LITTLE
ACCUMULATION.

&&

.AVIATION...MTNS OBSCURED. LIGHT SNOW IS WIDESPREAD OVER THE HIGHER
TERRAIN AND ALSO IN THE WESTERN MAGIC VALLEY THIS MORNING...BUT WILL
DECREASE IN COVERAGE THIS AFTERNOON AND EVENING. SNOW LEVEL IS
AROUND 4000 FT. SURFACE WIND THROUGH TONIGHT WILL BE SOUTH OR
SOUTHEAST LESS THAN 10 KTS...EXCEPT KJER WHERE NE WINDS ARE 10-20
KTS. WINDS ALOFT... THROUGH 10 KFT MSL...WILL BE SE TO SW 15 TO 25
KTS TODAY AND TONIGHT.

&&

.PREV DISCUSSION...
SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...EP
AVIATION.....SP
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 161620
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
920 AM MST TUE DEC 16 2014

.DISCUSSION...SNOW AND RAIN SHOWERS ARE CONTINUING THIS MORNING AS
AN UPPER LOW IS STILL WORKING ITS WAY ACROSS COASTAL
CALIFORNIA...BRINGING MOISTURE TO OUR AREA. THESE SHOWERS ARE
STILL EXPECTED TO TAPER OFF AS TODAY PROGRESSES WITH LITTLE
ACCUMULATION.

&&

.AVIATION...MTNS OBSCURED. LIGHT SNOW IS WIDESPREAD OVER THE HIGHER
TERRAIN AND ALSO IN THE WESTERN MAGIC VALLEY THIS MORNING...BUT WILL
DECREASE IN COVERAGE THIS AFTERNOON AND EVENING. SNOW LEVEL IS
AROUND 4000 FT. SURFACE WIND THROUGH TONIGHT WILL BE SOUTH OR
SOUTHEAST LESS THAN 10 KTS...EXCEPT KJER WHERE NE WINDS ARE 10-20
KTS. WINDS ALOFT... THROUGH 10 KFT MSL...WILL BE SE TO SW 15 TO 25
KTS TODAY AND TONIGHT.

&&

.PREV DISCUSSION...
SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...EP
AVIATION.....SP
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS65 KBOI 161620
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
920 AM MST TUE DEC 16 2014

.DISCUSSION...SNOW AND RAIN SHOWERS ARE CONTINUING THIS MORNING AS
AN UPPER LOW IS STILL WORKING ITS WAY ACROSS COASTAL
CALIFORNIA...BRINGING MOISTURE TO OUR AREA. THESE SHOWERS ARE
STILL EXPECTED TO TAPER OFF AS TODAY PROGRESSES WITH LITTLE
ACCUMULATION.

&&

.AVIATION...MTNS OBSCURED. LIGHT SNOW IS WIDESPREAD OVER THE HIGHER
TERRAIN AND ALSO IN THE WESTERN MAGIC VALLEY THIS MORNING...BUT WILL
DECREASE IN COVERAGE THIS AFTERNOON AND EVENING. SNOW LEVEL IS
AROUND 4000 FT. SURFACE WIND THROUGH TONIGHT WILL BE SOUTH OR
SOUTHEAST LESS THAN 10 KTS...EXCEPT KJER WHERE NE WINDS ARE 10-20
KTS. WINDS ALOFT... THROUGH 10 KFT MSL...WILL BE SE TO SW 15 TO 25
KTS TODAY AND TONIGHT.

&&

.PREV DISCUSSION...
SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...EP
AVIATION.....SP
PREV SHORT TERM...LC
PREV LONG TERM....JA




000
FXUS66 KMFR 161346
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
546 AM PST TUE DEC 16 2014

.SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

.LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE...
A DISORGANIZED FRONTAL SYSTEM WILL CONTINUE TO PUSH SHOWERS
ACROSS THE AREA THIS MORNING PARTIALLY OBSCURING THE MOUNTAINS. IN
THE VALLEYS MOSTLY VFR CONDITIONS PREVAIL, WITH SOME MVFR ALONG
VALLEY EDGES AND LOCAL LIFR FOG. LOW PRESSURE APPROACHING FROM THE
SOUTHWEST WILL RESULT IN EAST WINDS ACROSS THE AREA TONIGHT
THROUGH WEDNESDAY MORNING. THIS WILL RESULT IN A DECREASE IN
SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST AND AWAY FROM THE
COAST INCREASING THE CHANCE OF IFR TO LIFR LOW CLOUDS AND FOG
THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE ORGANIZED
PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL

&&

.MARINE...UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS OR,
POSSIBLY, GALES, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
  WEDNESDAY FOR PZZ356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350.
- SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM THIS MORNING TO 10 PM
  PST THIS EVENING FOR PZZ370-376.

$$

TRW/NSK/BTL



000
FXUS66 KMFR 161346
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
546 AM PST TUE DEC 16 2014

.SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

.LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...
FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT
REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A MINOR
TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING MAINLY
THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY
THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO
SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS.
THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES
WILL LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE
MANY TRAVELERS ON THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW
IN CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK


&&

.AVIATION...BASED ON THE 16/12Z TAF CYCLE...
A DISORGANIZED FRONTAL SYSTEM WILL CONTINUE TO PUSH SHOWERS
ACROSS THE AREA THIS MORNING PARTIALLY OBSCURING THE MOUNTAINS. IN
THE VALLEYS MOSTLY VFR CONDITIONS PREVAIL, WITH SOME MVFR ALONG
VALLEY EDGES AND LOCAL LIFR FOG. LOW PRESSURE APPROACHING FROM THE
SOUTHWEST WILL RESULT IN EAST WINDS ACROSS THE AREA TONIGHT
THROUGH WEDNESDAY MORNING. THIS WILL RESULT IN A DECREASE IN
SHOWERS AND CLOUDS FOR AREAS ACROSS THE WEST AND AWAY FROM THE
COAST INCREASING THE CHANCE OF IFR TO LIFR LOW CLOUDS AND FOG
THERE TONIGHT IN WEDNESDAY MORNING. EXPECT MORE ORGANIZED
PRECIPITATION ALONG AND NEAR THE COAST AND ACROSS NORTHERN
CALIFORNIA THIS AFTERNOON THROUGH TUESDAY NIGHT. BTL

&&

.MARINE...UPDATED 300 AM PST TUE DEC 16 2014... FAIRLY LARGE WEST
SWELL WILL GRADUALLY SUBSIDE TODAY. SURFACE LOW PRESSURE CENTERED
NEAR 130 WEST EARLY THIS MORNING WILL APPROACH AND THEN MOVE ONTO
THE NORTHERN CALIFORNIA COAST TONIGHT. THIS WILL RESULT IN
INCREASING SOUTH WINDS AND BUILDING WIND SEAS, ESPECIALLY SOUTH OF
CAPE BLANCO, TODAY. WINDS WILL SHIFT AS THE LOW MOVES BY THIS
EVENING THROUGH WEDNESDAY MORNING. THURSDAY INTO FRIDAY A STRONGER
FRONT WILL BRING HIGH END SMALL CRAFT ADVISORY LEVEL WINDS OR,
POSSIBLY, GALES, AS WELL AS RAIN, AND STEEP SEAS.

VERY LARGE WEST SWELL AROUND 20 FEET AT A DOMINANT PERIOD OF 19
SECONDS IS EXPECTED TO ARRIVE ON FRIDAY. THIS LARGE LONG PERIOD
SWELL IS LIKELY TO RESULT IN WAVE ACTION THAT NEGATIVELY IMPACTS
FISHING VESSELS AND EQUIPMENT, SUCH AS CRAB POTS.  ADDITIONALLY,
THIS LARGE SWELL WOULD BRING LARGE BREAKERS AND HIGH SURF CONDITIONS
TO THE COAST. CONFIDENCE IS MODERATE AND GROWING THAT THIS LARGE
SWELL WILL IMPACT THE AREA AT THE MAGNITUDE INDICATED. STAY TUNED
FOR UPDATES ON THIS DEVELOPING LONGER PERIOD SWELL EVENT. BTL

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST
  WEDNESDAY FOR PZZ356-370-376.
- SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 4 PM PST THIS
  AFTERNOON FOR PZZ350.
- SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM THIS MORNING TO 10 PM
  PST THIS EVENING FOR PZZ370-376.

$$

TRW/NSK/BTL




000
FXUS66 KPQR 161131
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
330 AM PST TUE DEC 16 2014

.SYNOPSIS...A SERIES OF WEAK FRONTAL SYSTEMS CONTINUES TO MOVE
ONSHORE. HIGH PRESSURE REMAINS EAST OF THE CASCADES...PRODUCING
LOW-LEVEL OFFSHORE FLOW AND KEEPING THE AIR MASS DRY ENOUGH SO ONLY A
FEW LIGHT RAIN SHOWERS ARE ABLE TO REACH THE SURFACE. THIS PATTERN
WILL PREVAIL THROUGH MIDWEEK...THEN A STRONGER FRONT WILL BRING A
MORE SOLID SHOT OF RAIN TO THE AREA THURSDAY NIGHT. LOWERING SNOW
LEVELS SHOULD BRING SOME ACCUMULATING SNOW TO THE CASCADES FRIDAY AND
SATURDAY. HOWEVER...RISING SNOW LEVELS AND SUBTROPICAL MOISTURE
SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT THE
HIGHEST PEAKS LATE IN THE WEEKEND AND EARLY NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...LIGHT RAIN PERSISTS TODAY AS A
WEAK FRONTAL SYSTEM CONTINUES TO PUSH EAST OF THE FORECAST AREA EARLY
THIS MORNING. SURFACE OBSERVATIONS ARE REPORTING BETWEEN 0.01-0.05"
OF RAIN IN THE PAST 6 HOURS...EXCEPT FOR ALMOST 0.10" OF PRECIP OVER
THE COAST RANGE. THE NEXT FRONTAL SYSTEM CAN BE SEEN IN INFRARED
SATELLITE IMAGERY JUST OFF THE OREGON/CALIFORNIA COASTLINE THIS
MORNING. TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER
PORTIONS OF THE HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW
ACCUMULATIONS UP TO AN INCH OR SO ARE POSSIBLE THROUGH THIS MORNING.

EVEN WITH OFFSHORE FLOW PERSISTING...MODELS CONTINUE TO SHOW THE
EASTERLY GRADIENT STARTING TO SLACK OFF TODAY. GRADIENTS FURTHER
WEAKEN THROUGH LATE WED...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE
CASCADES.

MODELS REMAIN CONSISTENT IN SHOWING MUCH OF THE ENERGY ASSOCIATED
WITH THIS NEXT LOW PRES SYSTEM HEADING SOUTH INTO NORTHERN CALIFORNIA
LATER TODAY. AS A REULT...OFFSHORE LOW LEVEL FLOW BECOMES REINFORCED
WHILE FLOW ALOFT TURNS A BIT MORE SOUTHERLY...ALLOWING SHOWER
ACTIVITY TO DIMINISH BY THIS AFTERNOON. SHOWERS MAY LINGER LONGER
ALONG THE CENTRAL OREGON COAST THOUGH. MOISTURE BEGINS TO SPREAD
ACROSS THE AREA AS THE CENTER OF THE LOW PRES DRIFTS TOWARDS THE
OREGON/CALIFORNIA BORDER OVERNIGHT TONIGHT INTO WEDNESDAY MORNING.
THE UPPER LEVEL TROUGH AXIS MOVES INLAND MIDDAY WEDNESDAY AND
WEDNESDAY NIGHT... WHICH SHOULD BRING ANOTHER ROUND OF PRECIP TO THE
AREA. BRIEF UPPER LEVEL RIDGING DEVELOPS FOR THURSDAY...BUT A WARM
FRONT AHEAD OF THE NEXT ORGANIZED FRONTAL BAND COULD BRING A THREAT
FOR PRECIP BY EARLY THURSDAY AFTERNOON. EAST WINDS MAY PICK UP AGAIN
THROUGH THE GORGE AS THIS SYSTEM APPROACHES THE COAST. THIS STRONG
FRONTAL SYSTEM PUSHES INTO THE PACIFIC NORTHWEST FRIDAY...BRINGING A
DECENT BATCH OF PRECIP TO THE AREA AS WELL AS GUSTY SOUTH WINDS FOR
THE COAST.

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY NIGHT
THROUGH MONDAY...A COLD AIR UNSTABLE AIRMASS WILL FOLLOW A STRONG
FRONTAL SYSTEM AND KEEP SHOWERS GOING INTO FRIDAY NIGHT. SNOW LEVELS
SHOULD LOWER TO NEAR 4000 FT ON SO ACCUMULATING SNOW APPEARS LIKELY
FOR AT LEAST THE HIGHER PASSES. AN ADDITIONAL SHORTWAVE TROUGH OR TWO
COULD ENHANCE SHOWER ACTIVITY EARLY IN THE WEEKEND AND BRING MUCH
NEEDED SNOW TO THE HIGHER CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...VFR CONDITIONS EXPECTED TO CONTINUE AT MOST TAF SITES
THROUGH WEDNESDAY MORNING. HOWEVER...AS A WEAK FRONT MOVES ACROSS
THE REGION WE COULD SEE BRIEF PERIODS OF MVFR TO IFR CIGS AND VIS
UNDER LIGHT TO MODERATE RAIN BANDS.

LOW LEVEL STRATUS HAS DEVELOPED OVER THE SOUTHERN WILLAMETTE
VALLEY THIS MORNING BRINGING LIFR TO IFR CIGS. EXPECT LIFR TO IFR
CIGS TO CONTINUE THROUGH AROUND 18Z. CONDITIONS SHOULD IMPROVE TO
VFR BY TUE AFTERNOON.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS BETWEEN 4K TO 6K
FT THIS MORNING RISING TO AROUND 12K FT TUESDAY AFTERNOON. /64

&&

.MARINE...A WEAK FRONT WILL CONTINUE TO MOVE ACROSS THE WATERS
THIS MORNING. EXPECT SMALL CRAFT ADVISORY SEAS AND WINDS THROUGH
LATE TUESDAY MORNING. EXPECT SEAS TO STAY BELOW 10 FT THROUGH
EARLY WEDNESDAY MORNING. ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS
THE WATERS ON WEDNESDAY AND COULD BRING ANOTHER ROUND OF SMALL
CRAFT ADVISORY WINDS AND SEAS. A MUCH STRONGER SYSTEM LOOKS TO
MOVE IN LATE THURSDAY INTO EARLY FRIDAY AND COULD BRING STRONG
GALE FORCE GUSTS AND 20 FT SEAS. /64

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

WA...NONE.

PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PST TODAY FOR WATERS
     FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM-
     WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST THIS
     MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE
     OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM
    PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 161131
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
330 AM PST TUE DEC 16 2014

.SYNOPSIS...A SERIES OF WEAK FRONTAL SYSTEMS CONTINUES TO MOVE
ONSHORE. HIGH PRESSURE REMAINS EAST OF THE CASCADES...PRODUCING
LOW-LEVEL OFFSHORE FLOW AND KEEPING THE AIR MASS DRY ENOUGH SO ONLY A
FEW LIGHT RAIN SHOWERS ARE ABLE TO REACH THE SURFACE. THIS PATTERN
WILL PREVAIL THROUGH MIDWEEK...THEN A STRONGER FRONT WILL BRING A
MORE SOLID SHOT OF RAIN TO THE AREA THURSDAY NIGHT. LOWERING SNOW
LEVELS SHOULD BRING SOME ACCUMULATING SNOW TO THE CASCADES FRIDAY AND
SATURDAY. HOWEVER...RISING SNOW LEVELS AND SUBTROPICAL MOISTURE
SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT THE
HIGHEST PEAKS LATE IN THE WEEKEND AND EARLY NEXT WEEK.

&&

.SHORT TERM...TODAY THROUGH FRIDAY...LIGHT RAIN PERSISTS TODAY AS A
WEAK FRONTAL SYSTEM CONTINUES TO PUSH EAST OF THE FORECAST AREA EARLY
THIS MORNING. SURFACE OBSERVATIONS ARE REPORTING BETWEEN 0.01-0.05"
OF RAIN IN THE PAST 6 HOURS...EXCEPT FOR ALMOST 0.10" OF PRECIP OVER
THE COAST RANGE. THE NEXT FRONTAL SYSTEM CAN BE SEEN IN INFRARED
SATELLITE IMAGERY JUST OFF THE OREGON/CALIFORNIA COASTLINE THIS
MORNING. TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER
PORTIONS OF THE HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW
ACCUMULATIONS UP TO AN INCH OR SO ARE POSSIBLE THROUGH THIS MORNING.

EVEN WITH OFFSHORE FLOW PERSISTING...MODELS CONTINUE TO SHOW THE
EASTERLY GRADIENT STARTING TO SLACK OFF TODAY. GRADIENTS FURTHER
WEAKEN THROUGH LATE WED...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE
CASCADES.

MODELS REMAIN CONSISTENT IN SHOWING MUCH OF THE ENERGY ASSOCIATED
WITH THIS NEXT LOW PRES SYSTEM HEADING SOUTH INTO NORTHERN CALIFORNIA
LATER TODAY. AS A REULT...OFFSHORE LOW LEVEL FLOW BECOMES REINFORCED
WHILE FLOW ALOFT TURNS A BIT MORE SOUTHERLY...ALLOWING SHOWER
ACTIVITY TO DIMINISH BY THIS AFTERNOON. SHOWERS MAY LINGER LONGER
ALONG THE CENTRAL OREGON COAST THOUGH. MOISTURE BEGINS TO SPREAD
ACROSS THE AREA AS THE CENTER OF THE LOW PRES DRIFTS TOWARDS THE
OREGON/CALIFORNIA BORDER OVERNIGHT TONIGHT INTO WEDNESDAY MORNING.
THE UPPER LEVEL TROUGH AXIS MOVES INLAND MIDDAY WEDNESDAY AND
WEDNESDAY NIGHT... WHICH SHOULD BRING ANOTHER ROUND OF PRECIP TO THE
AREA. BRIEF UPPER LEVEL RIDGING DEVELOPS FOR THURSDAY...BUT A WARM
FRONT AHEAD OF THE NEXT ORGANIZED FRONTAL BAND COULD BRING A THREAT
FOR PRECIP BY EARLY THURSDAY AFTERNOON. EAST WINDS MAY PICK UP AGAIN
THROUGH THE GORGE AS THIS SYSTEM APPROACHES THE COAST. THIS STRONG
FRONTAL SYSTEM PUSHES INTO THE PACIFIC NORTHWEST FRIDAY...BRINGING A
DECENT BATCH OF PRECIP TO THE AREA AS WELL AS GUSTY SOUTH WINDS FOR
THE COAST.

.LONG TERM...NO CHANGES. PREVIOUS DISCUSSION FOLLOWS...FRIDAY NIGHT
THROUGH MONDAY...A COLD AIR UNSTABLE AIRMASS WILL FOLLOW A STRONG
FRONTAL SYSTEM AND KEEP SHOWERS GOING INTO FRIDAY NIGHT. SNOW LEVELS
SHOULD LOWER TO NEAR 4000 FT ON SO ACCUMULATING SNOW APPEARS LIKELY
FOR AT LEAST THE HIGHER PASSES. AN ADDITIONAL SHORTWAVE TROUGH OR TWO
COULD ENHANCE SHOWER ACTIVITY EARLY IN THE WEEKEND AND BRING MUCH
NEEDED SNOW TO THE HIGHER CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...VFR CONDITIONS EXPECTED TO CONTINUE AT MOST TAF SITES
THROUGH WEDNESDAY MORNING. HOWEVER...AS A WEAK FRONT MOVES ACROSS
THE REGION WE COULD SEE BRIEF PERIODS OF MVFR TO IFR CIGS AND VIS
UNDER LIGHT TO MODERATE RAIN BANDS.

LOW LEVEL STRATUS HAS DEVELOPED OVER THE SOUTHERN WILLAMETTE
VALLEY THIS MORNING BRINGING LIFR TO IFR CIGS. EXPECT LIFR TO IFR
CIGS TO CONTINUE THROUGH AROUND 18Z. CONDITIONS SHOULD IMPROVE TO
VFR BY TUE AFTERNOON.

KPDX AND APPROACHES...VFR CONDITIONS WITH CIGS BETWEEN 4K TO 6K
FT THIS MORNING RISING TO AROUND 12K FT TUESDAY AFTERNOON. /64

&&

.MARINE...A WEAK FRONT WILL CONTINUE TO MOVE ACROSS THE WATERS
THIS MORNING. EXPECT SMALL CRAFT ADVISORY SEAS AND WINDS THROUGH
LATE TUESDAY MORNING. EXPECT SEAS TO STAY BELOW 10 FT THROUGH
EARLY WEDNESDAY MORNING. ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS
THE WATERS ON WEDNESDAY AND COULD BRING ANOTHER ROUND OF SMALL
CRAFT ADVISORY WINDS AND SEAS. A MUCH STRONGER SYSTEM LOOKS TO
MOVE IN LATE THURSDAY INTO EARLY FRIDAY AND COULD BRING STRONG
GALE FORCE GUSTS AND 20 FT SEAS. /64

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

WA...NONE.

PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON PST TODAY FOR WATERS
     FROM CAPE SHOALWATER WA TO CASCADE HEAD OR FROM 10 TO 60 NM-
     WATERS FROM CASCADE HEAD TO FLORENCE OR FROM 10 TO 60 NM.

     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST THIS
     MORNING FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE
     OR OUT 60 NM.

     SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR UNTIL 4 AM
    PST WEDNESDAY.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPDT 161127 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
328 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 161127 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
328 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 161127 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
328 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 161127 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATE
NATIONAL WEATHER SERVICE PENDLETON OR
328 AM PST TUE DEC 16 2014

UPDATED AVIATION DISCUSSION

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...12Z TAFS...COMPLICATED WEATHER PATTERN IS IN STORE EARLY
IN THE TAF PERIOD.  LIGHT PRECIPITATION IS POSSIBLE THRU 16/20Z IN
CENT OR AND THRU 17/00Z FOR WA/OR BORDER AND S WA.  TEMPERATURES
SUPPORT -SN AT KRDM AND KBDN...REMAINING TAF SITES SHOULD EXPERIENCE
-SHRA OR BRIEF PERIODS OF -FZRA.  ACCUMULATIONS ARE EXPECTED TO BE
LIGHT.  OTHERWISE...THE OTHER CHALLENGE WILL BE CIG/VIS ISSUES DUE
TO FOG AND LOW STRATUS.  LIFR/IFR CONDITIONS ARE EXPECTED AT NEARLY
ALL TAF SITES THRU 16/18Z BEFORE IMPROVING TO MVFR AS CLOUDS LIFT
AND PRECIP ENDS.  LIGHT WINDS AOB 10 KTS ALONG WITH INVERSIONS NEAR
THE SFC SUPPORT LOW STRATUS/FOG REDEVELOPMENT AFT 17/00Z WITH
IFR/MVFR CIG/VIS POSSIBLE AFT 17/06Z.  AVIATION DISCUSSIONS ARE NOT
UPDATED FOR TAF AMENDMENTS.  BIEDA

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98







000
FXUS66 KPDT 161032
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LIGHT RAIN/SNOW WILL
MOVE ACROSS THE AREA THROUGH TONIGHT AND TOMORROW MORNING BEFORE
EXITING THE AREA AFTER 18Z. VERY LIGHT FREEZING RAIN IS POSSIBLE AT
KALW AND KPSC BUT DUE TO THE LOW PROBABILITY, LIGHT AMOUNTS AND
POSSIBILITY OF TEMPERATURES WARMING ENOUGH FOR RAIN HAVE NOT
MENTIONED IT IN THE TAFS. ALL TAF SITES WILL HAVE AT LEAST
OCCASIONAL MVFR/IFR CONDITION DUE TO THE RAIN/SNOW. AFTER 18Z
TOMORROW, CONDITIONS WILL REMAIN OVERCAST BUT WILL GENERALLY IMPROVE
TO MVFR/VFR EXCEPT AT KALW. WINDS WILL REMAIN BELOW 15 KTS FOR THE
NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98








000
FXUS66 KPDT 161032
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LIGHT RAIN/SNOW WILL
MOVE ACROSS THE AREA THROUGH TONIGHT AND TOMORROW MORNING BEFORE
EXITING THE AREA AFTER 18Z. VERY LIGHT FREEZING RAIN IS POSSIBLE AT
KALW AND KPSC BUT DUE TO THE LOW PROBABILITY, LIGHT AMOUNTS AND
POSSIBILITY OF TEMPERATURES WARMING ENOUGH FOR RAIN HAVE NOT
MENTIONED IT IN THE TAFS. ALL TAF SITES WILL HAVE AT LEAST
OCCASIONAL MVFR/IFR CONDITION DUE TO THE RAIN/SNOW. AFTER 18Z
TOMORROW, CONDITIONS WILL REMAIN OVERCAST BUT WILL GENERALLY IMPROVE
TO MVFR/VFR EXCEPT AT KALW. WINDS WILL REMAIN BELOW 15 KTS FOR THE
NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98








000
FXUS66 KPDT 161032
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LIGHT RAIN/SNOW WILL
MOVE ACROSS THE AREA THROUGH TONIGHT AND TOMORROW MORNING BEFORE
EXITING THE AREA AFTER 18Z. VERY LIGHT FREEZING RAIN IS POSSIBLE AT
KALW AND KPSC BUT DUE TO THE LOW PROBABILITY, LIGHT AMOUNTS AND
POSSIBILITY OF TEMPERATURES WARMING ENOUGH FOR RAIN HAVE NOT
MENTIONED IT IN THE TAFS. ALL TAF SITES WILL HAVE AT LEAST
OCCASIONAL MVFR/IFR CONDITION DUE TO THE RAIN/SNOW. AFTER 18Z
TOMORROW, CONDITIONS WILL REMAIN OVERCAST BUT WILL GENERALLY IMPROVE
TO MVFR/VFR EXCEPT AT KALW. WINDS WILL REMAIN BELOW 15 KTS FOR THE
NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98








000
FXUS66 KPDT 161032
AFDPDT

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
230 AM PST TUE DEC 16 2014

.SHORT TERM...TODAY THROUGH THURSDAY. UPPER LEVEL TROUGH MOVING
ACROSS THE PACIFIC NORTHWEST TODAY. SATELLITE SHOWS THE SYSTEM IS
FAIRLY WEAK WITH MUCH OF THE ENERGY PASSING THROUGH CALIFORNIA.
EXPECT CLOUDY SKIES TODAY WITH SOME LIGHT PRECIPITATION IN THE FORM
OF SNOW, FREEZING RAIN OR RAIN. MOST OF THIS WILL BE IN THE MORNING.
AREAS OF LOW CLOUDS AND FOG WILL CONTINUE THROUGH THE MORNING AS
WELL. A BRIEF BREAK IN THE PRECIPITATION TONIGHT ALTHOUGH SKIES
SHOULD REMAIN MOSTLY CLOUDY WITH PATCHY FOG. ANOTHER UPPER TROUGH
MOVES THROUGH WEDNESDAY WITH A MIX OF LIGHT SNOW AND RAIN. A RIDGE
WILL BUILD OVER THE REGION LATE WEDNESDAY NIGHT INTO THURSDAY. HIGHS
THE NEXT SEVERAL DAY WILL BE IN THE 30S TO LOWER 40S. WINDS
REMAINING LIGHT EXCEPT FOR SOME SOUTH WIND IN THE GRANDE RONDE
VALLEY. 94

.LONG TERM...THURSDAY NIGHT THROUGH MONDAY NIGHT...THE REGION WILL
BE BETWEEN WEATHER SYSTEMS THURSDAY NIGHT THRU FRIDAY MORNING AS A
SHORTWAVE RIDGE MOVES OVER THE AREA.  BY MIDDAY FRIDAY...ANOTHER
WEATHER SYSTEM WITH AN ASSOCIATED COLD FRONT WILL BE MOVE EASTWARD
INTO REGION.  INCREASING SOUTH TO SOUTHEAST PRESSURE GRADIENTS AHEAD
OF THE FRONT MAY INCREASE WINDS ALONG THE CENTRAL TO NORTHEAST
OREGON HIGHLANDS AS WELL AS THE GRANDE RONDE VALLEY.  A CHANCE OF
PRECIPITATION IS POSSIBLE AS THE FRONT SWINGS THROUGH THE AREA WITH
SNOW LEVELS BOTTOMING OUT TO AROUND 1500 FEET BY SATURDAY MORNING. A
BROAD SCALE TROUGH WILL SET UP JUST OFF THE PACIFIC COAST WITH AN
ANCHORING LOW IN THE GULF OF ALASKA THAT WILL SEND SHORTWAVE TROUGHS
THROUGH THE REGION ALONG WITH A MOISTURE LADEN WEST TO EAST JET.
SHORTWAVE TROUGHS WILL MOVE ACROSS THE REGION SATURDAY NIGHT THRU
MONDAY NIGHT WITH ONE COMING THROUGH ALMOST DAILY.  THIS SHOULD
ALLOW FOR A CHANCE OF PRECIPITATION TO CONTINUE REGION WIDE DURING
THE LATTER PORTION OF THE PERIOD.  IN ADDITION...SOUTHERLY PRESSURE
GRADIENTS WILL REMAIN ELEVATED SUNDAY AND MONDAY BRINGING BREEZY
CONDITIONS TO THE CWA WITH STRONGER WINDS ALONG THE HIGHLANDS THE
WIND PRONE GRANDE RONDE VALLEY.  TEMPERATURES WILL ALSO BE ON THE
RISE AS A WARM FRONT SWINGS THROUGH SUNDAY NIGHT THRU MONDAY
MORNING.  TEMPERATURES TO START THE PERIOD WILL BE NEAR SEASONAL
NORMS RISING TO 10 DEGREES ABOVE SEASONAL NORMS BY MONDAY.  BIEDA

&&

.AVIATION...PREVIOUS DISCUSSION...06Z TAFS...LIGHT RAIN/SNOW WILL
MOVE ACROSS THE AREA THROUGH TONIGHT AND TOMORROW MORNING BEFORE
EXITING THE AREA AFTER 18Z. VERY LIGHT FREEZING RAIN IS POSSIBLE AT
KALW AND KPSC BUT DUE TO THE LOW PROBABILITY, LIGHT AMOUNTS AND
POSSIBILITY OF TEMPERATURES WARMING ENOUGH FOR RAIN HAVE NOT
MENTIONED IT IN THE TAFS. ALL TAF SITES WILL HAVE AT LEAST
OCCASIONAL MVFR/IFR CONDITION DUE TO THE RAIN/SNOW. AFTER 18Z
TOMORROW, CONDITIONS WILL REMAIN OVERCAST BUT WILL GENERALLY IMPROVE
TO MVFR/VFR EXCEPT AT KALW. WINDS WILL REMAIN BELOW 15 KTS FOR THE
NEXT 24 HOURS. 76

&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  37  29  38  31 /  50  10  20  30
ALW  38  31  39  32 /  40  10  20  30
PSC  37  29  38  31 /  40  10  20  20
YKM  38  30  37  28 /  50  10  20  20
HRI  37  29  38  31 /  50  10  20  20
ELN  38  29  37  27 /  50  10  30  30
RDM  38  27  40  26 /  40  20  30  20
LGD  37  29  39  29 /  60  10  20  30
GCD  37  27  39  28 /  50  20  30  30
DLS  40  35  41  32 /  50  20  30  30

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

97/98/98








000
FXUS66 KMFR 161015
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
215 AM PST TUE DEC 16 2014

.SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

.LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...FRIDAY THROUGH
MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT REACHING THE COAST.
EVERYTHING POINTS TO THIS STORM BEING A MINOR TO MODERATE IMPACT
EVENT...WITH MODERATE WINDS AFFECTING MAINLY THE USUAL
SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY THE SHASTA
VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO SNOW
LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS. THIS
FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH BASICALLY 60
KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO PRECIPITATION
SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES WILL LIKELY SEE
ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE MANY TRAVELERS ON
THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN ACCORDINGLY.
INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW IN CRATER
LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR RAIN/SNOW
MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST SNOW
LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK

&&

.AVIATION...BASED ON THE 15/06Z TAF CYCLE...A MIX OF VFR AND MVFR
CEILINGS WILL CONTINUE ACROSS THE REGION AS A FRONTAL SYSTEM
PUSHES THROUGH. AFTER MVFR/IFR INLAND OVERNIGHT, MOST AREAS SHOULD
BEGIN TO LIFT DURING THE MORNING. SOME LIGHT SHOWERS ARE ALSO
POSSIBLE OVERNIGHT, BUT THE MAIN BELT OF PRECIPITATION WILL NOT
ARRIVE UNTIL TUESDAY AFTERNOON. THE EXCEPTION WILL BE THE AREA
NEAR MT SHASTA CITY, WHERE PRECIPITATION IS LIKELY TO BE ONGOING
FOR THE NEXT 24 HOURS. FOR THE EAST SIDE AND NORTHERN CALIFORNIA,
ANY PRECIPITATION WILL FALL AS MOSTLY SNOW, RESULTING IN PERIODS OF
REDUCED VISIBILITIES. OTHERWISE, EXPECT MAINLY VFR IN SHOWERS
THROUGH THE REMAINDER OF THE TAF PERIOD. -BPN

&&

.MARINE...UPDATED 500 PM PST MON DEC 15 2014...MODERATE SOUTH WINDS
WILL CONTINUE INTO THIS EVENING THEN DECREASE. STEEP AND CHOPPY SEAS
CONTINUE TONIGHT DUE TO A MIX OF LONG PERIOD 12 TO 15 FT WEST SWELL
AT 16 SECONDS AND CHOPPY 5 TO 8 FT WIND SEAS. SEAS WILL TRANSITION
TO SWELL DOMINATED TONIGHT AND TUESDAY MORNING AS WIND SEAS LOWER
BUT WILL REMAIN STEEP ABOVE 10 FEET.

ANOTHER LOW PRESSURE SYSTEM  WILL ARRIVE TUESDAY WITH WINDS AND SEAS
LIKELY TO INCREASE AGAIN, MAINLY FOR THE OUTER COASTAL WATERS. THIS
LOW IS EXPECTED TO BRING SMALL CRAFT CONDITIONS TO THE OUTER WATERS
TUESDAY AFTERNOON AND EVENING AND GUSTS MAY REACH OCCASIONAL GALE
FORCE OVER THE WATERS BEYOND 20 NM SOUTH OF CAPE BLANCO. DUE TO
MODEL VARIABILITY WITH THE TRACK AND STRENGTH OF THIS SYSTEM,
CONFIDENCE IS HIGH FOR CONDITIONS REACHING SMALL CRAFT FOR PORTIONS
OF THE OUTER COASTAL WATERS  BUT LOW TO MODERATE IN GALE OR
HAZARDOUS SEAS WARNING CONDITIONS DEVELOPING TUESDAY AFTERNOON AND
EVENING.

ON WEDNESDAY, A BRIEF PERIOD OF HIGH PRESSURE IS EXPECTED OVER THE
WATERS. THEN A MODERATE TO STRONG FRONT MOVES INTO THE WATERS
THURSDAY BRINGING THE POTENTIAL FOR HIGH END SMALL CRAFT WINDS OR
GALES. THEN FRIDAY INTO SATURDAY...LARGE LONG PERIOD SWELL IS
EXPECTED TO BUILD INTO THE WATERS AND MAY REACH 20 FT WITH A
DOMINANT PERIOD AROUND 19 SECONDS.  THIS LARGE LONG PERIOD SWELL MAY
RESULT IN WAVE ACTION THAT IMPACTS FISHING VESSELS AND EQUIPMENT,
SUCH AS FOR THE CRAB INDUSTRY.  ADDITIONALLY THE LARGE LONG PERIOD
WEST SWELL MAY BRING LARGE BREAKERS AND HIGH SURF CONDITIONS TO THE
COAST. /CC

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
     10 AM PST THIS MORNING FOR PZZ350-356.
  SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM THIS MORNING TO 10 PM
     PST THIS EVENING FOR PZZ370-376.
  SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM PST THIS
     EVENING FOR PZZ370-376.

$$




000
FXUS66 KMFR 161015
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
215 AM PST TUE DEC 16 2014

.SHORT TERM...SOME CHANGES ARE BEING MADE TO THE SHORT TERM
FORECAST THIS MORNING, PARTICULARLY FOR SNOW AROUND THE MT.
SHASTA AREA, WHICH I WILL GET TO IN A MOMENT.

A WEAK UPPER TROUGH AXIS IS MOVING THROUGH OUR AREA RIGHT NOW BUT
IS LARGELY UNEVENTFUL FOR MOST OF US. THERE ARE SHOWERS AROUND,
BUT THE STEADIER PRECIPITATION IS OCCURRING ONLY IN THE CASCADES,
ALONG THE SOUTH COAST, AND IN THE SHASTA AREA. PER CAMERAS, SNOW
IS FALLING LIGHTLY BUT STEADILY AROUND DIAMOND LAKE AND ON
SNOWMAN`S SUMMIT EAST OF MT. SHASTA CITY, AND IT IS COVERING THE
ROADS IN BOTH LOCATIONS, BUT IT DOESN`T LOOK LIKE THEY`VE HAD
MUCH ACCUMULATION. IT IS ALSO SNOWING AND OCCASIONALLY MIXING WITH
RAIN IN MT. SHASTA CITY WHERE TEMPERATURES ARE JUST A BIT TOO WARM
(34F) TO GET ANY ACCUMULATIONS ON THE ROADWAYS.

MODELS SHOW ALL OF THIS BACKING OFF A LITTLE THIS MORNING AS THE
TROUGH WEAKENS AND MOVES NORTH OF US. AT THE SAME TIME, A STRONGER
TROUGH CURRENTLY NEAR 130W WILL CUT OFF AND MOVE TOWARD CAPE
MENDOCINO THIS AFTERNOON THEN OPEN UP A BIT AS IT MOVES ACROSS OUR
AREA TONIGHT INTO WEDNESDAY. THIS SYSTEM WILL NOT BE A GREAT
PRECIPITATION PRODUCER FOR MOST OF OUR AREA, SO I WOULD CATEGORIZE
IT AS A HIGH POP/LOW QPF TYPE SYSTEM. THE ONE EXCEPTION WILL BE
OVER CENTRAL SISKIYOU COUNTY WHERE UPSLOPE FLOW WILL RESULT IN
HEAVIER PRECIPITATION WHICH WILL LOCALLY FORCE SNOW LEVELS DOWN.
ALL MODEL GUIDANCE SHOWS PARAMETERS SUFFICIENT TO PRODUCE SNOW
THIS EVENING INTO WEDNESDAY MORNING OVER THE REGION, INCLUDING
ALONG I-5 IN THE MT. SHASTA AREA. WITH 1000-700MB THICKNESSES
AROUND 2860M, 850MB TEMPS NEAR 0C, SOUTHERLY 700 MB FLOW OF
40-50KT, AND MODEL SOUNDINGS ALL BELOW 0C, IT IS LIKELY THAT MOST
OF THE PRECIP FALLS AS SNOW AROUND MT. SHASTA TONIGHT, THE ONLY
QUESTION IS HOW MUCH. THIS WILL BE A VERY WET SNOW WITH LOW
RATIOS, BUT MODEL QPF IS HIGH ENOUGH TO GET 3 OR MORE INCHES DOWN
TO THE INTERSTATE, WITH MORE LIKELY AT HIGHER ELEVATIONS INCLUDING
THE SKI AREA. UPPER FLOW BECOMES MORE SOUTHWESTERLY BY WEDNESDAY
MORNING WHICH WILL LIMIT ACCUMULATIONS, BUT I WILL BE ISSUING A
WINTER WEATHER ADVISORY TO COVER THIS.

RESIDUAL SHOWERS LAST INTO WEDNESDAY NIGHT, BUT THEN WE WILL DRY
OUT THURSDAY AS A TRANSIENT RIDGES BUILDS OVER THE PACNW. THE
THINKING IN THE LONG RANGE STILL LOOKS SOLID AND THE FORECAST IS
LARGELY UNCHANGED, SO THE PREVIOUS DISCUSSION FOLLOWS. -WRIGHT

.LONG TERM...ISSUED 251 PM PST MON DEC 15 2014...FRIDAY THROUGH
MONDAY...FRIDAY STARTS OFF WITH A COLD FRONT REACHING THE COAST.
EVERYTHING POINTS TO THIS STORM BEING A MINOR TO MODERATE IMPACT
EVENT...WITH MODERATE WINDS AFFECTING MAINLY THE USUAL
SUSPECTS...THE COAST...AND EAST SIDE...AND POTENTIALLY THE SHASTA
VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS FRONT...SO SNOW
LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION STARTS. THIS
FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH BASICALLY 60
KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO PRECIPITATION
SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES WILL LIKELY SEE
ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE MANY TRAVELERS ON
THIS LAST-FRIDAY-BEFORE- CHRISTMAS SHOULD PLAN ACCORDINGLY.
INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW IN CRATER
LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR RAIN/SNOW
MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST SNOW
LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK

&&

.AVIATION...BASED ON THE 15/06Z TAF CYCLE...A MIX OF VFR AND MVFR
CEILINGS WILL CONTINUE ACROSS THE REGION AS A FRONTAL SYSTEM
PUSHES THROUGH. AFTER MVFR/IFR INLAND OVERNIGHT, MOST AREAS SHOULD
BEGIN TO LIFT DURING THE MORNING. SOME LIGHT SHOWERS ARE ALSO
POSSIBLE OVERNIGHT, BUT THE MAIN BELT OF PRECIPITATION WILL NOT
ARRIVE UNTIL TUESDAY AFTERNOON. THE EXCEPTION WILL BE THE AREA
NEAR MT SHASTA CITY, WHERE PRECIPITATION IS LIKELY TO BE ONGOING
FOR THE NEXT 24 HOURS. FOR THE EAST SIDE AND NORTHERN CALIFORNIA,
ANY PRECIPITATION WILL FALL AS MOSTLY SNOW, RESULTING IN PERIODS OF
REDUCED VISIBILITIES. OTHERWISE, EXPECT MAINLY VFR IN SHOWERS
THROUGH THE REMAINDER OF THE TAF PERIOD. -BPN

&&

.MARINE...UPDATED 500 PM PST MON DEC 15 2014...MODERATE SOUTH WINDS
WILL CONTINUE INTO THIS EVENING THEN DECREASE. STEEP AND CHOPPY SEAS
CONTINUE TONIGHT DUE TO A MIX OF LONG PERIOD 12 TO 15 FT WEST SWELL
AT 16 SECONDS AND CHOPPY 5 TO 8 FT WIND SEAS. SEAS WILL TRANSITION
TO SWELL DOMINATED TONIGHT AND TUESDAY MORNING AS WIND SEAS LOWER
BUT WILL REMAIN STEEP ABOVE 10 FEET.

ANOTHER LOW PRESSURE SYSTEM  WILL ARRIVE TUESDAY WITH WINDS AND SEAS
LIKELY TO INCREASE AGAIN, MAINLY FOR THE OUTER COASTAL WATERS. THIS
LOW IS EXPECTED TO BRING SMALL CRAFT CONDITIONS TO THE OUTER WATERS
TUESDAY AFTERNOON AND EVENING AND GUSTS MAY REACH OCCASIONAL GALE
FORCE OVER THE WATERS BEYOND 20 NM SOUTH OF CAPE BLANCO. DUE TO
MODEL VARIABILITY WITH THE TRACK AND STRENGTH OF THIS SYSTEM,
CONFIDENCE IS HIGH FOR CONDITIONS REACHING SMALL CRAFT FOR PORTIONS
OF THE OUTER COASTAL WATERS  BUT LOW TO MODERATE IN GALE OR
HAZARDOUS SEAS WARNING CONDITIONS DEVELOPING TUESDAY AFTERNOON AND
EVENING.

ON WEDNESDAY, A BRIEF PERIOD OF HIGH PRESSURE IS EXPECTED OVER THE
WATERS. THEN A MODERATE TO STRONG FRONT MOVES INTO THE WATERS
THURSDAY BRINGING THE POTENTIAL FOR HIGH END SMALL CRAFT WINDS OR
GALES. THEN FRIDAY INTO SATURDAY...LARGE LONG PERIOD SWELL IS
EXPECTED TO BUILD INTO THE WATERS AND MAY REACH 20 FT WITH A
DOMINANT PERIOD AROUND 19 SECONDS.  THIS LARGE LONG PERIOD SWELL MAY
RESULT IN WAVE ACTION THAT IMPACTS FISHING VESSELS AND EQUIPMENT,
SUCH AS FOR THE CRAB INDUSTRY.  ADDITIONALLY THE LARGE LONG PERIOD
WEST SWELL MAY BRING LARGE BREAKERS AND HIGH SURF CONDITIONS TO THE
COAST. /CC

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 10 AM PST
     WEDNESDAY FOR CAZ082-083-282-284.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL
     10 AM PST THIS MORNING FOR PZZ350-356.
  SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM THIS MORNING TO 10 PM
     PST THIS EVENING FOR PZZ370-376.
  SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM PST THIS
     EVENING FOR PZZ370-376.

$$



000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA




000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 160947
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
247 AM MST TUE DEC 16 2014

.SHORT TERM...A WEAK WAVE MOVED NEWD THROUGH OUR CWA MONDAY EVENING
WITH A LITTLE LIGHT SNOW...WAVE IS ALREADY NORTH OF OUR CWA.
ANOTHER...SLIGHTLY STRONGER...WAVE WILL TRACK NEWD THROUGH IDAHO
ZONES TODAY BUT AS OF 09Z KCBX RADAR SEES NO ECHOES IN OUR CWA.
A WEAKER WAVE WILL TRACK NEWD THROUGH HARNEY COUNTY WEDNESDAY.
MODELS HAVE GENERALLY INCREASED POPS FROM PREVIOUS RUNS AND OUR
FORECAST DOES THE SAME.  SHADOWING FROM THE OWYHEE MOUNTAINS
WILL LIMIT PCPN AND POPS IN THE TREASURE VALLEY.  TOTAL QPF WILL
REMAIN LIGHT THROUGHOUT OUR CWA AND NO WINTER WX HIGHLIGHTS ARE
PLANNED.  TEMPS WILL BE MILD ENOUGH FOR RAIN OR MIXED RAIN AND SNOW
IN THE SNAKE BASIN.  LIGHT SNOW IN THE MOUNTAINS.  WINDS WILL BE
LIGHT SOUTHEAST THROUGH WEDNESDAY.

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...LITTLE CHANGE IN THE
LATEST MODEL RUNS THROUGH THE EXTENDED PERIOD.  SPLITTING TROUGH
WILL MOVE EAST OVER THE FORECAST AREA THURSDAY NIGHT WITH THE
NORTHERN SECTION OF THE TROUGH MOVING OVER OREGON AND IDAHO.  THIS
WILL BRING A CHANCE OF MOUNTAIN SNOW AND A SLIGHT CHANCE OF VALLEY
RAIN AND SNOW WEDNESDAY NIGHT DECREASING FROM WEST TO EAST ON
THURSDAY.  WEAK RIDGE OF HIGH PRESSURE WILL MOVE OVER THE AREA
THURSDAY NIGHT AND FRIDAY BUT MODELS SHOW THAT IT WILL MOVE EAST
RATHER QUICKLY WITH ONLY A BRIEF PERIOD OF DRY CONDITIONS.  MODELS
STILL SHOW SOME TIMING ISSUES SO WILL BE HARD TO PINPOINT A DRY
PERIOD IN THE FORECAST AS THE NEXT UPPER LEVEL TROUGH IS RIGHT ON
THE HEELS OF THE RIDGE.  AT THIS TIME MOST LOCATIONS WILL BE DRY
THURSDAY NIGHT BUT DEPENDING ON HOW QUICKLY THE NEXT UPPER LEVEL
TROUGH MOVES INTO THE WEST COAST WE COULD SEE A SLIGHT CHANCE OF
PRECIPITATION OVER SOUTHEAST OREGON LATE THURSDAY NIGHT/EARLY FRIDAY
MORNING.  FRIDAY THROUGH FRIDAY NIGHT THE NEXT UPPER LEVEL TROUGH
WILL MOVE INTO THE WEST COAST AND WEAKEN AS IT MOVES EAST.  THIS
WILL BRING A CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH AT
LEAST FRIDAY NIGHT.  FOR THE WEEKEND AND INTO EARLY NEXT WEEK LOOKS
LIKE A CHANGE IN THE WEATHER PATTERN AS A ZONAL FLOW SETS UP OVER
THE PACIFIC NORTHWEST.  THERE ARE WEAK WAVES MOVING THROUGH THE FLOW
WITH TIMING DIFFERENCES BETWEEN MODELS.  WITH SOME UNCERTAINTY IN
THE MODELS WILL BROAD BRUSH POPS OVER THE WEEKEND AND INTO EARLY
NEXT WEEK WITH A CHANCE OF SNOW IN THE MOUNTAINS AND A SLIGHT CHANCE
OF RAIN/SNOW IN THE VALLEYS.  TEMPERATURES WILL REMAIN SLIGHTLY
ABOVE NORMAL THROUGH THE EXTENDED PERIOD.

&&

.AVIATION...AREAS OF -SN AND MOUNTAIN OBSCURATION OVER THE FORECAST
AREA THROUGH THE DAY WITH OCCASIONAL MVFR/IFR CONDITIONS...INCLUDING
KBNO...KBKE AND KMYL.  SNOW MAY CHANGE TO RAIN OR A RAIN-SNOW MIX
BELOW 3K FEET MSL.  SURFACE WINDS GENERALLY 10 KNOTS OR
LESS...EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER
WITH EASTERLY WINDS OF 15-20 KNOTS.  WINDS ALOFT WILL BE SOUTHERLY
20-25 KNOTS UP THROUGH 10K FEET MSL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

SHORT TERM...LC
LONG TERM....JA
AVIATION.....JA



000
FXUS65 KBOI 160544
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1044 PM MST MON DEC 15 2014

.DISCUSSION...UPDATE...LEADING IMPULSE OF VERY LIGHT SNOW AT 1030
PM EXTENDED ACROSS NORTHERN MALHEUR AND BAKER COUNTIES...THROUGH
THE UPPER WEISER BASIN THEN WEAKENED IN AN ARC AROUND FROM
CAMBRIDGE TO BANNER SUMMIT AND THE WEST MAGIC VALLEY. SNOW ENDED
AT TWIN FALLS AIRPORT AS OF 1023 PM AND WILL END AT JEROME BY
MIDNIGHT. TEMPERATURES WILL COOL BELOW FREEZING SO PERRINE/HANSEN
BRIDGES MAY BECOME SLICK FROM THE LIGHT SNOW THAT MOVED THROUGH.
ALSO SNOW WILL DECREASE ACROSS EAST CENTRAL OREGON AND THE WEISER
BASIN THROUGH 1 AM BUT ANOTHER AREA OF LIFT AND LIGHT SNOW /OVER
LAKE COUNTY AT 1030 PM/ IS EXPECTED TO LIFT SOUTH TO NORTH ACROSS
EASTERN OREGON FOR THE REST OF THE NIGHT. FORECAST UPDATED FOR
LOWER SNOW LEVELS TONIGHT. POPS AND TEMPS ON TRACK. GUSTY WINDS
FROM JEROME THROUGH MOUNTAIN HOME 20 TO 35 MPH /10-20 MPH AT
BOISE/ AND LIGHT ACROSS SHELTERED LOWER VALLEYS INCLUDING NAMPA
THROUGH ONTARIO.

&&

.AVIATION....AREAS OF -SN ACROSS EASTERN OREGON OVERNIGHT WITH
OCCASIONAL MVFR/IFR...INCLUDING KBNO AND POSSIBLY KBKE VICINITY.
LESS COVERAGE ON THE IDAHO SIDE BUT DO EXPECT OCCASIONAL MVFR-IFR IN
-SN OVER MOUNTAINS. IFR IN FOG LIKELY AT KMYL AFTER 06Z...LIFTING
BY 20Z. CHANCE OF -SN OVER THE TREASURE AND MAGIC VALLEYS OVERNIGHT
BUT VFR SHOULD PREVAIL.  SURFACE WINDS GENERALLY 10 KNOTS OR LESS...
EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER WITH
EASTERLY WINDS OF 15-25 KNOTS. WINDS ALOFT...SOUTHERLY 15-25 KNOTS
UP THROUGH 10K FEET MSL. CHANCE OF MVFR IN -SN TUESDAY...ESPECIALLY
OVER THE MOUNTAINS.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLOUD COVER IS
MOVING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH WITH ITS AXIS
ALONG THE CALIFORNIA COAST. AS IT MOVES IN...THE PRESSURE GRADIENT
WILL TIGHTEN UP WITH HIGHER PRESSURE TO THE EAST...WHICH WILL
BRING SOME GUSTY EAST/SOUTHEAST WINDS TO THE WESTERN MAGIC VALLEY
AND TREASURE VALLEY THROUGH TUESDAY. PRECIP CHANCES WILL BEGIN
THIS EVENING IN SE OREGON AND SPREAD THROUGH SW IDAHO THROUGH THE
NIGHT. QPF AMOUNTS LOOK TO BE VERY LOW...WITH MOST AREAS EXPECTED
TO RECEIVE LESS THAN ONE TENTH OF AN INCH. SNOW LEVELS WILL BE AT
VALLEY FLOORS TONIGHT AND SLOWLY RISE TO AROUND 3500-4000 FEET BY
WEDNESDAY MID-DAY. SNOW ACCUMULATIONS OVER THE NEXT 36 HOURS IN
THE MOUNTAINS ARE EXPECTED TO BE UNDER AN INCH. HOWEVER...PRECIP
CHANCES TAPER OFF EARLY WEDNESDAY AS THE TROUGH AXIS WILL BE NEAR
THE CA/NV BORDER AND THE UPPER LOW BEGINS TO DIGS SOUTH.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...SPLITTING TROUGH WILL
CONTINUE TO SLOWLY MIGRATE EASTWARD ACROSS THE WEST WEDNESDAY NIGHT-
THURSDAY. THE NORTHERN PORTION OF THE TROUGH WILL MOVE ACROSS
OREGON/IDAHO FOR A CHANCE OF MOUNTAIN SNOW/SLIGHT CHANCE OF VALLEY
RAIN AND SNOW. MODELS AGREE THAT THE QPF WILL BE LOW. A SHORT-LIVED
UPPER RIDGE AND ACCOMPANYING DRIER CONDITIONS WILL SLIDE INTO THE
AREA THURSDAY NIGHT. ANOTHER UPPER TROUGH ARRIVES ON FRIDAY FOR A
CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH FRIDAY NIGHT.
THE PATTERN CHANGES OVER THE WEEKEND THROUGH EARLY NEXT WEEK AS AN
UPPER RIDGE STRENGTHENS OFF THE CALIFORNIA COAST AND A MOIST PACIFIC
FLOW RIDES OVER THE TOP OF THE RIDGE AND PUSHES INTO THE PACIFIC
NORTHWEST. THIS WILL BRING A BETTER CHANCE OF PRECIP AND POTENTIALLY
HIGHER QPF TO THE MOUNTAINS. TEMPERATURES WILL REMAIN SLIGHTLY ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....TL
PREV SHORT TERM...EP
PREV LONG TERM....BW/DD




000
FXUS65 KBOI 160544
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1044 PM MST MON DEC 15 2014

.DISCUSSION...UPDATE...LEADING IMPULSE OF VERY LIGHT SNOW AT 1030
PM EXTENDED ACROSS NORTHERN MALHEUR AND BAKER COUNTIES...THROUGH
THE UPPER WEISER BASIN THEN WEAKENED IN AN ARC AROUND FROM
CAMBRIDGE TO BANNER SUMMIT AND THE WEST MAGIC VALLEY. SNOW ENDED
AT TWIN FALLS AIRPORT AS OF 1023 PM AND WILL END AT JEROME BY
MIDNIGHT. TEMPERATURES WILL COOL BELOW FREEZING SO PERRINE/HANSEN
BRIDGES MAY BECOME SLICK FROM THE LIGHT SNOW THAT MOVED THROUGH.
ALSO SNOW WILL DECREASE ACROSS EAST CENTRAL OREGON AND THE WEISER
BASIN THROUGH 1 AM BUT ANOTHER AREA OF LIFT AND LIGHT SNOW /OVER
LAKE COUNTY AT 1030 PM/ IS EXPECTED TO LIFT SOUTH TO NORTH ACROSS
EASTERN OREGON FOR THE REST OF THE NIGHT. FORECAST UPDATED FOR
LOWER SNOW LEVELS TONIGHT. POPS AND TEMPS ON TRACK. GUSTY WINDS
FROM JEROME THROUGH MOUNTAIN HOME 20 TO 35 MPH /10-20 MPH AT
BOISE/ AND LIGHT ACROSS SHELTERED LOWER VALLEYS INCLUDING NAMPA
THROUGH ONTARIO.

&&

.AVIATION....AREAS OF -SN ACROSS EASTERN OREGON OVERNIGHT WITH
OCCASIONAL MVFR/IFR...INCLUDING KBNO AND POSSIBLY KBKE VICINITY.
LESS COVERAGE ON THE IDAHO SIDE BUT DO EXPECT OCCASIONAL MVFR-IFR IN
-SN OVER MOUNTAINS. IFR IN FOG LIKELY AT KMYL AFTER 06Z...LIFTING
BY 20Z. CHANCE OF -SN OVER THE TREASURE AND MAGIC VALLEYS OVERNIGHT
BUT VFR SHOULD PREVAIL.  SURFACE WINDS GENERALLY 10 KNOTS OR LESS...
EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER WITH
EASTERLY WINDS OF 15-25 KNOTS. WINDS ALOFT...SOUTHERLY 15-25 KNOTS
UP THROUGH 10K FEET MSL. CHANCE OF MVFR IN -SN TUESDAY...ESPECIALLY
OVER THE MOUNTAINS.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLOUD COVER IS
MOVING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH WITH ITS AXIS
ALONG THE CALIFORNIA COAST. AS IT MOVES IN...THE PRESSURE GRADIENT
WILL TIGHTEN UP WITH HIGHER PRESSURE TO THE EAST...WHICH WILL
BRING SOME GUSTY EAST/SOUTHEAST WINDS TO THE WESTERN MAGIC VALLEY
AND TREASURE VALLEY THROUGH TUESDAY. PRECIP CHANCES WILL BEGIN
THIS EVENING IN SE OREGON AND SPREAD THROUGH SW IDAHO THROUGH THE
NIGHT. QPF AMOUNTS LOOK TO BE VERY LOW...WITH MOST AREAS EXPECTED
TO RECEIVE LESS THAN ONE TENTH OF AN INCH. SNOW LEVELS WILL BE AT
VALLEY FLOORS TONIGHT AND SLOWLY RISE TO AROUND 3500-4000 FEET BY
WEDNESDAY MID-DAY. SNOW ACCUMULATIONS OVER THE NEXT 36 HOURS IN
THE MOUNTAINS ARE EXPECTED TO BE UNDER AN INCH. HOWEVER...PRECIP
CHANCES TAPER OFF EARLY WEDNESDAY AS THE TROUGH AXIS WILL BE NEAR
THE CA/NV BORDER AND THE UPPER LOW BEGINS TO DIGS SOUTH.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...SPLITTING TROUGH WILL
CONTINUE TO SLOWLY MIGRATE EASTWARD ACROSS THE WEST WEDNESDAY NIGHT-
THURSDAY. THE NORTHERN PORTION OF THE TROUGH WILL MOVE ACROSS
OREGON/IDAHO FOR A CHANCE OF MOUNTAIN SNOW/SLIGHT CHANCE OF VALLEY
RAIN AND SNOW. MODELS AGREE THAT THE QPF WILL BE LOW. A SHORT-LIVED
UPPER RIDGE AND ACCOMPANYING DRIER CONDITIONS WILL SLIDE INTO THE
AREA THURSDAY NIGHT. ANOTHER UPPER TROUGH ARRIVES ON FRIDAY FOR A
CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH FRIDAY NIGHT.
THE PATTERN CHANGES OVER THE WEEKEND THROUGH EARLY NEXT WEEK AS AN
UPPER RIDGE STRENGTHENS OFF THE CALIFORNIA COAST AND A MOIST PACIFIC
FLOW RIDES OVER THE TOP OF THE RIDGE AND PUSHES INTO THE PACIFIC
NORTHWEST. THIS WILL BRING A BETTER CHANCE OF PRECIP AND POTENTIALLY
HIGHER QPF TO THE MOUNTAINS. TEMPERATURES WILL REMAIN SLIGHTLY ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....TL
PREV SHORT TERM...EP
PREV LONG TERM....BW/DD




000
FXUS65 KBOI 160544
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1044 PM MST MON DEC 15 2014

.DISCUSSION...UPDATE...LEADING IMPULSE OF VERY LIGHT SNOW AT 1030
PM EXTENDED ACROSS NORTHERN MALHEUR AND BAKER COUNTIES...THROUGH
THE UPPER WEISER BASIN THEN WEAKENED IN AN ARC AROUND FROM
CAMBRIDGE TO BANNER SUMMIT AND THE WEST MAGIC VALLEY. SNOW ENDED
AT TWIN FALLS AIRPORT AS OF 1023 PM AND WILL END AT JEROME BY
MIDNIGHT. TEMPERATURES WILL COOL BELOW FREEZING SO PERRINE/HANSEN
BRIDGES MAY BECOME SLICK FROM THE LIGHT SNOW THAT MOVED THROUGH.
ALSO SNOW WILL DECREASE ACROSS EAST CENTRAL OREGON AND THE WEISER
BASIN THROUGH 1 AM BUT ANOTHER AREA OF LIFT AND LIGHT SNOW /OVER
LAKE COUNTY AT 1030 PM/ IS EXPECTED TO LIFT SOUTH TO NORTH ACROSS
EASTERN OREGON FOR THE REST OF THE NIGHT. FORECAST UPDATED FOR
LOWER SNOW LEVELS TONIGHT. POPS AND TEMPS ON TRACK. GUSTY WINDS
FROM JEROME THROUGH MOUNTAIN HOME 20 TO 35 MPH /10-20 MPH AT
BOISE/ AND LIGHT ACROSS SHELTERED LOWER VALLEYS INCLUDING NAMPA
THROUGH ONTARIO.

&&

.AVIATION....AREAS OF -SN ACROSS EASTERN OREGON OVERNIGHT WITH
OCCASIONAL MVFR/IFR...INCLUDING KBNO AND POSSIBLY KBKE VICINITY.
LESS COVERAGE ON THE IDAHO SIDE BUT DO EXPECT OCCASIONAL MVFR-IFR IN
-SN OVER MOUNTAINS. IFR IN FOG LIKELY AT KMYL AFTER 06Z...LIFTING
BY 20Z. CHANCE OF -SN OVER THE TREASURE AND MAGIC VALLEYS OVERNIGHT
BUT VFR SHOULD PREVAIL.  SURFACE WINDS GENERALLY 10 KNOTS OR LESS...
EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER WITH
EASTERLY WINDS OF 15-25 KNOTS. WINDS ALOFT...SOUTHERLY 15-25 KNOTS
UP THROUGH 10K FEET MSL. CHANCE OF MVFR IN -SN TUESDAY...ESPECIALLY
OVER THE MOUNTAINS.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLOUD COVER IS
MOVING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH WITH ITS AXIS
ALONG THE CALIFORNIA COAST. AS IT MOVES IN...THE PRESSURE GRADIENT
WILL TIGHTEN UP WITH HIGHER PRESSURE TO THE EAST...WHICH WILL
BRING SOME GUSTY EAST/SOUTHEAST WINDS TO THE WESTERN MAGIC VALLEY
AND TREASURE VALLEY THROUGH TUESDAY. PRECIP CHANCES WILL BEGIN
THIS EVENING IN SE OREGON AND SPREAD THROUGH SW IDAHO THROUGH THE
NIGHT. QPF AMOUNTS LOOK TO BE VERY LOW...WITH MOST AREAS EXPECTED
TO RECEIVE LESS THAN ONE TENTH OF AN INCH. SNOW LEVELS WILL BE AT
VALLEY FLOORS TONIGHT AND SLOWLY RISE TO AROUND 3500-4000 FEET BY
WEDNESDAY MID-DAY. SNOW ACCUMULATIONS OVER THE NEXT 36 HOURS IN
THE MOUNTAINS ARE EXPECTED TO BE UNDER AN INCH. HOWEVER...PRECIP
CHANCES TAPER OFF EARLY WEDNESDAY AS THE TROUGH AXIS WILL BE NEAR
THE CA/NV BORDER AND THE UPPER LOW BEGINS TO DIGS SOUTH.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...SPLITTING TROUGH WILL
CONTINUE TO SLOWLY MIGRATE EASTWARD ACROSS THE WEST WEDNESDAY NIGHT-
THURSDAY. THE NORTHERN PORTION OF THE TROUGH WILL MOVE ACROSS
OREGON/IDAHO FOR A CHANCE OF MOUNTAIN SNOW/SLIGHT CHANCE OF VALLEY
RAIN AND SNOW. MODELS AGREE THAT THE QPF WILL BE LOW. A SHORT-LIVED
UPPER RIDGE AND ACCOMPANYING DRIER CONDITIONS WILL SLIDE INTO THE
AREA THURSDAY NIGHT. ANOTHER UPPER TROUGH ARRIVES ON FRIDAY FOR A
CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH FRIDAY NIGHT.
THE PATTERN CHANGES OVER THE WEEKEND THROUGH EARLY NEXT WEEK AS AN
UPPER RIDGE STRENGTHENS OFF THE CALIFORNIA COAST AND A MOIST PACIFIC
FLOW RIDES OVER THE TOP OF THE RIDGE AND PUSHES INTO THE PACIFIC
NORTHWEST. THIS WILL BRING A BETTER CHANCE OF PRECIP AND POTENTIALLY
HIGHER QPF TO THE MOUNTAINS. TEMPERATURES WILL REMAIN SLIGHTLY ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....TL
PREV SHORT TERM...EP
PREV LONG TERM....BW/DD




000
FXUS65 KBOI 160544
AFDBOI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BOISE ID
1044 PM MST MON DEC 15 2014

.DISCUSSION...UPDATE...LEADING IMPULSE OF VERY LIGHT SNOW AT 1030
PM EXTENDED ACROSS NORTHERN MALHEUR AND BAKER COUNTIES...THROUGH
THE UPPER WEISER BASIN THEN WEAKENED IN AN ARC AROUND FROM
CAMBRIDGE TO BANNER SUMMIT AND THE WEST MAGIC VALLEY. SNOW ENDED
AT TWIN FALLS AIRPORT AS OF 1023 PM AND WILL END AT JEROME BY
MIDNIGHT. TEMPERATURES WILL COOL BELOW FREEZING SO PERRINE/HANSEN
BRIDGES MAY BECOME SLICK FROM THE LIGHT SNOW THAT MOVED THROUGH.
ALSO SNOW WILL DECREASE ACROSS EAST CENTRAL OREGON AND THE WEISER
BASIN THROUGH 1 AM BUT ANOTHER AREA OF LIFT AND LIGHT SNOW /OVER
LAKE COUNTY AT 1030 PM/ IS EXPECTED TO LIFT SOUTH TO NORTH ACROSS
EASTERN OREGON FOR THE REST OF THE NIGHT. FORECAST UPDATED FOR
LOWER SNOW LEVELS TONIGHT. POPS AND TEMPS ON TRACK. GUSTY WINDS
FROM JEROME THROUGH MOUNTAIN HOME 20 TO 35 MPH /10-20 MPH AT
BOISE/ AND LIGHT ACROSS SHELTERED LOWER VALLEYS INCLUDING NAMPA
THROUGH ONTARIO.

&&

.AVIATION....AREAS OF -SN ACROSS EASTERN OREGON OVERNIGHT WITH
OCCASIONAL MVFR/IFR...INCLUDING KBNO AND POSSIBLY KBKE VICINITY.
LESS COVERAGE ON THE IDAHO SIDE BUT DO EXPECT OCCASIONAL MVFR-IFR IN
-SN OVER MOUNTAINS. IFR IN FOG LIKELY AT KMYL AFTER 06Z...LIFTING
BY 20Z. CHANCE OF -SN OVER THE TREASURE AND MAGIC VALLEYS OVERNIGHT
BUT VFR SHOULD PREVAIL.  SURFACE WINDS GENERALLY 10 KNOTS OR LESS...
EXCEPT IN THE SNAKE RIVER VALLEY FROM KBOI EAST TO KTWF/KJER WITH
EASTERLY WINDS OF 15-25 KNOTS. WINDS ALOFT...SOUTHERLY 15-25 KNOTS
UP THROUGH 10K FEET MSL. CHANCE OF MVFR IN -SN TUESDAY...ESPECIALLY
OVER THE MOUNTAINS.

&&

.PREV DISCUSSION...
SHORT TERM...TONIGHT THROUGH WEDNESDAY...CLOUD COVER IS
MOVING INTO THE AREA AHEAD OF AN UPPER LEVEL TROUGH WITH ITS AXIS
ALONG THE CALIFORNIA COAST. AS IT MOVES IN...THE PRESSURE GRADIENT
WILL TIGHTEN UP WITH HIGHER PRESSURE TO THE EAST...WHICH WILL
BRING SOME GUSTY EAST/SOUTHEAST WINDS TO THE WESTERN MAGIC VALLEY
AND TREASURE VALLEY THROUGH TUESDAY. PRECIP CHANCES WILL BEGIN
THIS EVENING IN SE OREGON AND SPREAD THROUGH SW IDAHO THROUGH THE
NIGHT. QPF AMOUNTS LOOK TO BE VERY LOW...WITH MOST AREAS EXPECTED
TO RECEIVE LESS THAN ONE TENTH OF AN INCH. SNOW LEVELS WILL BE AT
VALLEY FLOORS TONIGHT AND SLOWLY RISE TO AROUND 3500-4000 FEET BY
WEDNESDAY MID-DAY. SNOW ACCUMULATIONS OVER THE NEXT 36 HOURS IN
THE MOUNTAINS ARE EXPECTED TO BE UNDER AN INCH. HOWEVER...PRECIP
CHANCES TAPER OFF EARLY WEDNESDAY AS THE TROUGH AXIS WILL BE NEAR
THE CA/NV BORDER AND THE UPPER LOW BEGINS TO DIGS SOUTH.

LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY...SPLITTING TROUGH WILL
CONTINUE TO SLOWLY MIGRATE EASTWARD ACROSS THE WEST WEDNESDAY NIGHT-
THURSDAY. THE NORTHERN PORTION OF THE TROUGH WILL MOVE ACROSS
OREGON/IDAHO FOR A CHANCE OF MOUNTAIN SNOW/SLIGHT CHANCE OF VALLEY
RAIN AND SNOW. MODELS AGREE THAT THE QPF WILL BE LOW. A SHORT-LIVED
UPPER RIDGE AND ACCOMPANYING DRIER CONDITIONS WILL SLIDE INTO THE
AREA THURSDAY NIGHT. ANOTHER UPPER TROUGH ARRIVES ON FRIDAY FOR A
CHANCE OF VALLEY RAIN/SNOW AND MOUNTAIN SNOW THROUGH FRIDAY NIGHT.
THE PATTERN CHANGES OVER THE WEEKEND THROUGH EARLY NEXT WEEK AS AN
UPPER RIDGE STRENGTHENS OFF THE CALIFORNIA COAST AND A MOIST PACIFIC
FLOW RIDES OVER THE TOP OF THE RIDGE AND PUSHES INTO THE PACIFIC
NORTHWEST. THIS WILL BRING A BETTER CHANCE OF PRECIP AND POTENTIALLY
HIGHER QPF TO THE MOUNTAINS. TEMPERATURES WILL REMAIN SLIGHTLY ABOVE
NORMAL.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...NONE.
OR...NONE.

&&

$$

WEATHER.GOV/BOISE

DISCUSSION...VM
AVIATION.....TL
PREV SHORT TERM...EP
PREV LONG TERM....BW/DD




000
FXUS66 KPDT 160532 AAA
AFDPDT

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
931 PM PST MON DEC 15 2014

UPDATED AVIATION DISCUSSION

.UPDATE...SNOW HAS BEEN REPORTED AT BEND, REDMOND, PRINEVILLE, AND
MADRAS. RADAR INDICATES LIGHT RETURNS FROM GRANT TO WASCO
COUNTIES BUT NO REPORTS YET FROM THE GROUND. EXPECT LIGHT PATCHY
RAIN/SNOW TO MOVE ACROSS THE REST OF THE CWA BY MORNING. 0Z NAM
SUPPORTS CURRENT FORECAST OF HIGH POPS/LOW QPF. WEB CAMS DO NOT
SHOW ANY AREAS OF SIGNIFICANT ACCUMULATION THOUGH LIGHT AMOUNTS
ARE VISIBLE. WILL CONTINUE TO MONITOR WEATHER BUT CURRENT FORECAST
IS ON TRACK. COONFIELD

&&

.AVIATION...06Z TAFS...LIGHT RAIN/SNOW WILL MOVE ACROSS THE AREA
THROUGH TONIGHT AND TOMORROW MORNING BEFORE EXITING THE AREA AFTER
18Z. VERY LIGHT FREEZING RAIN IS POSSIBLE AT KALW AND KPSC BUT DUE
TO THE LOW PROBABILITY, LIGHT AMOUNTS AND POSSIBILITY OF
TEMPERATURES WARMING ENOUGH FOR RAIN HAVE NOT MENTIONED IT IN THE
TAFS. ALL TAF SITES WILL HAVE AT LEAST OCCASIONAL MVFR/IFR CONDITION
DUE TO THE RAIN/SNOW. AFTER 18Z TOMORROW, CONDITIONS WILL REMAIN
OVERCAST BUT WILL GENERALLY IMPROVE TO MVFR/VFR EXCEPT AT KALW.
WINDS WILL REMAIN BELOW 15 KTS FOR THE NEXT 24 HOURS. 76

&&

.PREV DISC... /ISSUED 357 PM PST MON DEC 15 2014/

SHORT TERM...TONIGHT THROUGH THURSDAY...SATELLITE CONTINUES TO SHOW
A SURGE OF MOISTURE COMING UP OUT OF CALIFORNIA THAT WILL MOVE OVER
THE FORECAST AREA TONIGHT AND TUESDAY. MODELS AGREE IN MOVING THIS
ACROSS THE AREA BUT WEAKENING AS IT DOES. SO HAVE GONE WITH A HIGH
CHANCE OF PRECIPITATION BUT LOW AMOUNTS OF PRECIPITATION FOR THE
FORECAST AREA. THIS WILL TRANSLATE INTO A LIGHT SNOW ACCUMULATION
EVENT GENERALLY BELOW ADVISORY CRITERIA SO NO HIGHLIGHTS AT THIS
TIME. THE MOISTURE WILL EXIT TO THE NORTHEAST LATE TUESDAY WITH
SHOWERS DECREASING AND COMING TO END FOR PORTIONS OF THE AREA. THE
NEXT SYSTEM WILL ARRIVE LATE TUESDAY NIGHT AND WEDNESDAY BUT IT TOO
WILL BE A WEAK SYSTEM BUT WITH LOW CHANCE OF PRECIPITATION AND
MINIMAL PRECIPITATION AMOUNTS. HIGH PRESSURE WILL BUILD OVER THE
REGION WEDNESDAY NIGHT AND THURSDAY WITH YET ANOTHER SYSTEM ARRIVING
LATE THURSDAY INTO FRIDAY. FOG AND STRATUS CLOUDS WILL CONTINUED TO
BE TRAPPED BENEATH INVERSIONS.

LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS CONTINUE TO SHOW
A TRANSITORY RIDGE MOVING ACROSS THE AREA THURSDAY NIGHT. BEHIND THE
RIDGE A TROUGH WILL APPROACHING THE OREGON/WASHINGTON COAST AND A
FRONT WILL MOVE ACROSS THE CASCADES LATE THAT NIGHT. EXPECT THAT
THERE WILL BE A CHANCE OF RAIN AND MOUNTAIN SNOW AS FAR EAST AS THE
YAKIMA AND KITTITAS VALLEYS SOUTH INTO CENTRAL OREGON BY SUNRISE
WITH A SLIGHT CHANCE OF RAIN AND SNOW TO THE EAST. FRIDAY WILL SEE A
CHANCE OF RAIN AND MOUNTAIN SNOW ACROSS THE AREA TAPERING OFF FRIDAY
NIGHT. SATURDAY LOOKS LIKE A BREAK AS THE TROUGH IS REPLACED BY A
DRIER WESTERLY FLOW. THE LOWER ELEVATIONS SHOULD BE DRY BUT THERE
WILL BE SOME UPSLOPE RAIN AND SNOW SHOWERS MAINLY IN THE MOUNTAINS.
ANOTHER FRONT WILL COME ASHORE SATURDAY NIGHT AND SUNDAY FOR ANOTHER
CHANCE OF RAIN AND MOUNTAIN SNOW. THIS SYSTEM WILL BE WARMER AND
TEMPERATURES WILL BEGIN RISING. A FLAT RIDGE IN THE EASTERN PACIFIC
WILL CONTINUE TO STEER MOISTURE INTO THE AREA SUNDAY NIGHT AND
MONDAY. MODELS HAVE SOME DIFFERENCES SO FOR NOW HAVE PLACED A SLIGHT
CHANCE OF RAIN IN THE LOWER ELEVATIONS WITH A CHANCE OF RAIN AND
SNOW IN THE MOUNTAINS. SUNDAY THROUGH MONDAY LOOK LIKE IT WILL BE
BREEZY. TEMPERATURES WILL START OUT FRIDAY AND SATURDAY IN THE MID
30S TO LOWER 40S THEN WARM TO THE MID TO UPPER 40S WITH MID 30S TO
LOWER 40S IN THE MOUNTAINS. PERRY



&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  32  37  28  36 /  60  60  10  20
ALW  31  37  30  38 /  60  60  10  20
PSC  32  36  29  36 /  60  60  10  20
YKM  31  36  30  36 /  60  60  10  20
HRI  33  37  29  36 /  60  60  10  20
ELN  30  37  30  37 /  60  60  10  20
RDM  29  39  26  38 /  80  20  20  20
LGD  31  38  29  39 /  60  60  10  20
GCD  30  39  29  40 /  70  60  20  20
DLS  36  40  35  39 /  60  60  20  20

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...AIR STAGNATION ADVISORY UNTIL 10 AM PST FRIDAY WAZ026>028.

&&

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON

$$

76/76/76








000
FXUS66 KPQR 160439
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
838 PM PST MON DEC 15 2014

.SYNOPSIS...A SERIES OF WEAK FRONTAL SYSTEMS CONTINUES TO MOVE
ONSHORE...WITH THE LATEST PIVOTING THROUGH WESTERN OREGON THIS
EVENING. HIGH PRESSURE REMAINS EAST OF THE CASCADES...PRODUCING
LOW-LEVEL OFFSHORE FLOW AND KEEPING THE AIR MASS DRY ENOUGH SO ONLY A
FEW LIGHT RAIN SHOWERS ARE ABLE TO REACH THE SURFACE. THIS PATTERN
WILL PREVAIL THROUGH MIDWEEK...THEN A STRONGER FRONT WILL BRING A
MORE SOLID SHOT OF RAIN TO THE AREA THURSDAY NIGHT. LOWERING SNOW
LEVELS SHOULD BRING SOME ACCUMULATING SNOW TO THE CASCADES FRIDAY AND
SATURDAY. HOWEVER...RISING SNOW LEVELS AND SUBTROPICAL MOISTURE
SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT THE
HIGHEST PEAKS LATE IN THE WEEKEND AND EARLY NEXT WEEK.

&&

.EVENING UPDATE...VERY LITTLE IN THE WAY OF CHANGE TO THE AFTERNOON
FORECAST PACKAGE THIS EVENING...AS FORECAST APPEARS TO BE SOLIDLY ON
TRACK. RADAR SHOWS LITTLE IN THE WAY OF MOISTURE ASSOCIATED WITH THE
LATEST WEAK FRONTAL SYSTEM PIVOTING THROUGH WESTERN OREGON.
ASSOCIATED FORCING IS WEAK WITH ONLY WEAK LOW TO MID-LEVEL
FRONTOGENESIS AND MEAGER JET DYNAMICS. THUS WE EXPECT ONLY A FEW
PERIODS OF LIGHT RAIN...OR POSSIBLY JUST SPRINKLES IN SOME AREAS AS
THE AIR MASS HAS BEEN DRIED OUT BY LOW-LEVEL OFFSHORE FLOW.
TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER PORTIONS OF THE
HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW ACCUMULATIONS UP TO AN INCH
OR SO ARE POSSIBLE THROUGH TUESDAY MORNING.

KTTD-KDLS GRADIENTS HAVE DECREASED IN MAGNITUDE...-5.8 MB AS OPPOSED
TO THE -7.2 MB WHICH RESULTED IN LAST NIGHTS GUSTY EASTERLY FLOW.
GRADIENTS SHOULD CONTINUE TO SLOWLY SLACKEN OVER THE NEXT COUPLE
DAYS...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE CASCADES. THERE
COULD BE BRIEF VARIATIONS IN THIS TREND...BUT OVERALL EXPECT EAST
WINDS TO BE SLOWLY RAMPING DOWN THE NEXT COUPLE DAYS. EAST WINDS MAY
PICK UP AGAIN THROUGH THE GORGE THU/THU NIGHT AS A STRONGER PACIFIC
FRONTAL SYSTEM APPROACHES THE COAST. THIS SYSTEM WILL BRING A BETTER
SHOT OF RAIN AND GUSTY SOUTH WINDS ALONG THE COAST AS WELL.  WEAGLE

.SHORT TERM...TONIGHT THROUGH THURSDAY...A COMPOSITE OF SATELLITE AND
RADAR IMAGERY SHOWS AN ELONGATED UPPER LEVEL TROUGH SLOWLY SLIDING
EASTWARD INTO THE PACIFIC NORTHWEST. OFF AND ON LIGHT RAIN HAS BEEN
OBSERVED ALONG THE COAST AND ACROSS THE SOUTHERN HALF OF THE
WILLAMETTE VALLEY TODAY. HOWEVER...QPF HAS BEEN MEAGER THUS FAR.
EXPECT THIS TREND TO CONTINUE...BUT AS THE UPPER LEVEL TROUGH AXIS
NUDGES EASTWARD...EXPECT LIGHT RAIN TO INCREASE ACROSS THE REST OF
NORTHWEST OREGON AND SOUTHWEST WASHINGTON OVERNIGHT AS THE LOWER
ATMOSPHERE MOISTENS A BIT.

THE NAM CONTINUES TO SUGGEST HEAVIER QPF WILL FALL ACROSS THE CENTRAL
COLUMBIA RIVER GORGE AND UPPER HOOD RIVER VALLEY OVERNIGHT...LIKELY
DUE TO A COMBINATION OF A WARM ADVECTION ALOFT AND LOW LEVEL UPSLOPE
FLOW INTO THE EAST SLOPES OF THE CASCADES. HOWEVER...AFTER
INVESTIGATING THE SREF ENSEMBLE MEMBERS...THE OPERATIONAL NAM IS THE
OUTLIER IN TERMS OF QPF VALUES FOR KDLS. AS A RESULT...QPF VALUES
WERE TRENDED TOWARDS THE SREF MEAN FOR THE CENTRAL COLUMBIA RIVER
GORGE AND UPPER HOOD RIVER VALLEY. GIVEN THE LOW LEVEL STRATUS IN
PLACE ACROSS THE COLUMBIA RIVER BASIN...DO NOT EXPECT TEMPERATURES
TO DROP DRAMATICALLY OVERNIGHT FROM THEIR CURRENT READINGS AROUND
HOOD RIVER AND PARKDALE. AS A RESULT...ANY PRECIPITATION SHOULD FALL
AS EITHER A COLD RAIN OR A RAIN/SNOW MIX AROUND HOOD RIVER AND AS
WET SNOW IN THE UPPER HOOD RIVER VALLEY. THUS...AN INCH OR TWO OF
SNOW APPEARS POSSIBLE ABOVE 1000 TO 1500 FT TONIGHT AROUND THE
CENTRAL COLUMBIA RIVER GORGE...BUT SUSPECT AMOUNTS APPROACHING THESE
NUMBERS COULD BE HARD TO COME BY EVEN IN THE UPPER HOOD RIVER VALLEY
BASED ON CURRENT TEMPERATURES AND MOST SREF QPF VALUES.

AN AREA OF ENHANCED CLOUD TOPS CURRENTLY NEAR 135W DUE WEST OF OREGON
WILL CONTINUE TO SPREAD EASTWARD TOWARDS THE COAST. MODELS ARE IN
REASONABLE AGREEMENT A SURFACE LOW PRESSURE WILL INTENSIFY OVERNIGHT
AND TUESDAY AS IT MOVES TOWARDS THE NORTHERN CALIFORNIA AND SOUTH
OREGON COAST. THIS SHOULD REINFORCE OFFSHORE LOW LEVEL FLOW AND TURN
OUR FLOW ALOFT A TOUCH MORE SOUTHERLY...WHICH SHOULD REDUCE SHOWER
ACTIVITY ON TUESDAY...PARTICULARLY DURING THE AFTERNOON AND EVENING
HOURS.

THE UPPER LEVEL TROUGH AXIS STILL LOOKS TO SWING THROUGH LATE
TUESDAY NIGHT INTO WEDNESDAY...PROBABLY BRINGING AN UPTICK IN SHOWER
ACTIVITY DURING THIS PERIOD. NOT ALL MODELS ARE ON BOARD WITH THIS
SCENARIO SO POPS WERE STILL KEPT IN THE HIGH END CHANCE TO LOW END
LIKELY RANGE FOR THIS TIME PERIOD...BUT SYNOPTICALLY THIS IDEA SEEMS
REASONABLE.

EVEN THOUGH SHORTWAVE RIDGING WILL BE PUSHING INTO THE REGION LATE
WEDNESDAY INTO EARLY THURSDAY...THE EC/SREF SUGGEST A WARM FRONT AND
LIGHT RAIN WILL PUSH INTO THE REGION ON THURSDAY...REDUCING THE
LENGTH OF OUR DRY WEATHER WINDOW. GIVEN THE GFS AND NAM KEEP US
RELATIVELY DRY DURING THIS PERIOD...POPS WERE HELD MAINLY IN THE
CHANCE RANGE FOR NOW ON THURSDAY. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS ARE IN GOOD
AGREEMENT A RELATIVELY STRONG FRONT WILL BRING A SOLID SHOT OF RAIN
TO THE AREA THURSDAY NIGHT INTO EARLY FRIDAY. FORTUNATELY...THIS WILL
BE FAIRLY TRANSIENT STORM SYSTEM SO HYDRO CONCERNS ARE LOW.

A COLD AIR UNSTABLE AIRMASS WILL FOLLOW AND KEEP SHOWERS GOING INTO
FRIDAY. SNOW LEVELS SHOULD LOWER TO NEAR 4000 FT ON FRIDAY SO
ACCUMULATING SNOW APPEARS LIKELY FOR AT LEAST THE HIGHER PASSES. AN
ADDITIONAL SHORTWAVE TROUGH OR TWO COULD ENHANCE SHOWER ACTIVITY
EARLY IN THE WEEKEND AND BRING MUCH NEEDED SNOW TO THE HIGHER
CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...VFR WITH INCREASING MID LEVEL CLOUDS THIS EVENING. A
WEAK FRONT OFF THE COAST WILL PUSH MVFR CIGS AGAINST THE COAST
THIS EVENING...AND POSSIBLY INTO THE INTERIOR AFTER 09Z. BEST
THREAT OF INLAND MVFR WILL BE S OF A KHIO TO KUAO LINE. NOT MUCH
CHANGE THROUGH DAY ON TUE...WITH PLENTY OF LOW TO MID VFR
CLOUDS...WITH AREAS OF MVFR CIGS THROUGH 18Z.

KPDX AND APPROACHES...VFR TONIGHT WITH CIGS LOWERING FROM 7K TO
NEAR 4K BY LATE TONIGHT. LIGHT TO MODERATE E WINDS CONTINUE
TONIGHT THEN EASE A BIT AFTER 15Z TUE.ROCKEY.

&&

.MARINE...A SERIES OF WEAK SYSTEMS WILL AFFECT THE WATERS FOR THE
NEXT SEVERAL DAYS. AS FIRST FRONT MOVES INTO THE REGION...WILL
HAVE SOUTH GUSTS 20 TO 25 KT TONIGHT ACROSS OUTER WATERS...THEN
WINDS EASE TUE AM.

SEAS GENERALLY 13 TO 16 FT THIS EVENING. WILL SEE A VERY VERY
SLOW DECREASE IN SEAS LATER TONIGHT INTO TUE AM...WITH SEAS 10 TO
12 TUE AM INTO EARLY TUE AFTERNOON. STILL THINK SEAS DROP BACK
UNDER 10 FT LATE TUE AFTERNOON OR EARLY EVENING.

NEXT ORGANIZED FRONT ARRIVES LATE THU INTO FRI. STRONG POTENTIAL
FOR GALE FORCE SOUTHERLY WINDS AT THAT TIME...WITH SEAS GETTING
BACK UP INTO THE 15 TO 20 FT RANGE.      ROCKEY.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON TUESDAY FOR THE
       OUTER WATERS...OR FROM CAPE SHOALWATER TO FLORENCE AND
       FROM 10 TO 60 MILES OFFSHORE.
    SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM TUE
       ON ALL WATERS.
    SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
       AND AGAIN FROM 10 AM TO 2 PM TUE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KPQR 160439
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
838 PM PST MON DEC 15 2014

.SYNOPSIS...A SERIES OF WEAK FRONTAL SYSTEMS CONTINUES TO MOVE
ONSHORE...WITH THE LATEST PIVOTING THROUGH WESTERN OREGON THIS
EVENING. HIGH PRESSURE REMAINS EAST OF THE CASCADES...PRODUCING
LOW-LEVEL OFFSHORE FLOW AND KEEPING THE AIR MASS DRY ENOUGH SO ONLY A
FEW LIGHT RAIN SHOWERS ARE ABLE TO REACH THE SURFACE. THIS PATTERN
WILL PREVAIL THROUGH MIDWEEK...THEN A STRONGER FRONT WILL BRING A
MORE SOLID SHOT OF RAIN TO THE AREA THURSDAY NIGHT. LOWERING SNOW
LEVELS SHOULD BRING SOME ACCUMULATING SNOW TO THE CASCADES FRIDAY AND
SATURDAY. HOWEVER...RISING SNOW LEVELS AND SUBTROPICAL MOISTURE
SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT THE
HIGHEST PEAKS LATE IN THE WEEKEND AND EARLY NEXT WEEK.

&&

.EVENING UPDATE...VERY LITTLE IN THE WAY OF CHANGE TO THE AFTERNOON
FORECAST PACKAGE THIS EVENING...AS FORECAST APPEARS TO BE SOLIDLY ON
TRACK. RADAR SHOWS LITTLE IN THE WAY OF MOISTURE ASSOCIATED WITH THE
LATEST WEAK FRONTAL SYSTEM PIVOTING THROUGH WESTERN OREGON.
ASSOCIATED FORCING IS WEAK WITH ONLY WEAK LOW TO MID-LEVEL
FRONTOGENESIS AND MEAGER JET DYNAMICS. THUS WE EXPECT ONLY A FEW
PERIODS OF LIGHT RAIN...OR POSSIBLY JUST SPRINKLES IN SOME AREAS AS
THE AIR MASS HAS BEEN DRIED OUT BY LOW-LEVEL OFFSHORE FLOW.
TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER PORTIONS OF THE
HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW ACCUMULATIONS UP TO AN INCH
OR SO ARE POSSIBLE THROUGH TUESDAY MORNING.

KTTD-KDLS GRADIENTS HAVE DECREASED IN MAGNITUDE...-5.8 MB AS OPPOSED
TO THE -7.2 MB WHICH RESULTED IN LAST NIGHTS GUSTY EASTERLY FLOW.
GRADIENTS SHOULD CONTINUE TO SLOWLY SLACKEN OVER THE NEXT COUPLE
DAYS...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE CASCADES. THERE
COULD BE BRIEF VARIATIONS IN THIS TREND...BUT OVERALL EXPECT EAST
WINDS TO BE SLOWLY RAMPING DOWN THE NEXT COUPLE DAYS. EAST WINDS MAY
PICK UP AGAIN THROUGH THE GORGE THU/THU NIGHT AS A STRONGER PACIFIC
FRONTAL SYSTEM APPROACHES THE COAST. THIS SYSTEM WILL BRING A BETTER
SHOT OF RAIN AND GUSTY SOUTH WINDS ALONG THE COAST AS WELL.  WEAGLE

.SHORT TERM...TONIGHT THROUGH THURSDAY...A COMPOSITE OF SATELLITE AND
RADAR IMAGERY SHOWS AN ELONGATED UPPER LEVEL TROUGH SLOWLY SLIDING
EASTWARD INTO THE PACIFIC NORTHWEST. OFF AND ON LIGHT RAIN HAS BEEN
OBSERVED ALONG THE COAST AND ACROSS THE SOUTHERN HALF OF THE
WILLAMETTE VALLEY TODAY. HOWEVER...QPF HAS BEEN MEAGER THUS FAR.
EXPECT THIS TREND TO CONTINUE...BUT AS THE UPPER LEVEL TROUGH AXIS
NUDGES EASTWARD...EXPECT LIGHT RAIN TO INCREASE ACROSS THE REST OF
NORTHWEST OREGON AND SOUTHWEST WASHINGTON OVERNIGHT AS THE LOWER
ATMOSPHERE MOISTENS A BIT.

THE NAM CONTINUES TO SUGGEST HEAVIER QPF WILL FALL ACROSS THE CENTRAL
COLUMBIA RIVER GORGE AND UPPER HOOD RIVER VALLEY OVERNIGHT...LIKELY
DUE TO A COMBINATION OF A WARM ADVECTION ALOFT AND LOW LEVEL UPSLOPE
FLOW INTO THE EAST SLOPES OF THE CASCADES. HOWEVER...AFTER
INVESTIGATING THE SREF ENSEMBLE MEMBERS...THE OPERATIONAL NAM IS THE
OUTLIER IN TERMS OF QPF VALUES FOR KDLS. AS A RESULT...QPF VALUES
WERE TRENDED TOWARDS THE SREF MEAN FOR THE CENTRAL COLUMBIA RIVER
GORGE AND UPPER HOOD RIVER VALLEY. GIVEN THE LOW LEVEL STRATUS IN
PLACE ACROSS THE COLUMBIA RIVER BASIN...DO NOT EXPECT TEMPERATURES
TO DROP DRAMATICALLY OVERNIGHT FROM THEIR CURRENT READINGS AROUND
HOOD RIVER AND PARKDALE. AS A RESULT...ANY PRECIPITATION SHOULD FALL
AS EITHER A COLD RAIN OR A RAIN/SNOW MIX AROUND HOOD RIVER AND AS
WET SNOW IN THE UPPER HOOD RIVER VALLEY. THUS...AN INCH OR TWO OF
SNOW APPEARS POSSIBLE ABOVE 1000 TO 1500 FT TONIGHT AROUND THE
CENTRAL COLUMBIA RIVER GORGE...BUT SUSPECT AMOUNTS APPROACHING THESE
NUMBERS COULD BE HARD TO COME BY EVEN IN THE UPPER HOOD RIVER VALLEY
BASED ON CURRENT TEMPERATURES AND MOST SREF QPF VALUES.

AN AREA OF ENHANCED CLOUD TOPS CURRENTLY NEAR 135W DUE WEST OF OREGON
WILL CONTINUE TO SPREAD EASTWARD TOWARDS THE COAST. MODELS ARE IN
REASONABLE AGREEMENT A SURFACE LOW PRESSURE WILL INTENSIFY OVERNIGHT
AND TUESDAY AS IT MOVES TOWARDS THE NORTHERN CALIFORNIA AND SOUTH
OREGON COAST. THIS SHOULD REINFORCE OFFSHORE LOW LEVEL FLOW AND TURN
OUR FLOW ALOFT A TOUCH MORE SOUTHERLY...WHICH SHOULD REDUCE SHOWER
ACTIVITY ON TUESDAY...PARTICULARLY DURING THE AFTERNOON AND EVENING
HOURS.

THE UPPER LEVEL TROUGH AXIS STILL LOOKS TO SWING THROUGH LATE
TUESDAY NIGHT INTO WEDNESDAY...PROBABLY BRINGING AN UPTICK IN SHOWER
ACTIVITY DURING THIS PERIOD. NOT ALL MODELS ARE ON BOARD WITH THIS
SCENARIO SO POPS WERE STILL KEPT IN THE HIGH END CHANCE TO LOW END
LIKELY RANGE FOR THIS TIME PERIOD...BUT SYNOPTICALLY THIS IDEA SEEMS
REASONABLE.

EVEN THOUGH SHORTWAVE RIDGING WILL BE PUSHING INTO THE REGION LATE
WEDNESDAY INTO EARLY THURSDAY...THE EC/SREF SUGGEST A WARM FRONT AND
LIGHT RAIN WILL PUSH INTO THE REGION ON THURSDAY...REDUCING THE
LENGTH OF OUR DRY WEATHER WINDOW. GIVEN THE GFS AND NAM KEEP US
RELATIVELY DRY DURING THIS PERIOD...POPS WERE HELD MAINLY IN THE
CHANCE RANGE FOR NOW ON THURSDAY. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS ARE IN GOOD
AGREEMENT A RELATIVELY STRONG FRONT WILL BRING A SOLID SHOT OF RAIN
TO THE AREA THURSDAY NIGHT INTO EARLY FRIDAY. FORTUNATELY...THIS WILL
BE FAIRLY TRANSIENT STORM SYSTEM SO HYDRO CONCERNS ARE LOW.

A COLD AIR UNSTABLE AIRMASS WILL FOLLOW AND KEEP SHOWERS GOING INTO
FRIDAY. SNOW LEVELS SHOULD LOWER TO NEAR 4000 FT ON FRIDAY SO
ACCUMULATING SNOW APPEARS LIKELY FOR AT LEAST THE HIGHER PASSES. AN
ADDITIONAL SHORTWAVE TROUGH OR TWO COULD ENHANCE SHOWER ACTIVITY
EARLY IN THE WEEKEND AND BRING MUCH NEEDED SNOW TO THE HIGHER
CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...VFR WITH INCREASING MID LEVEL CLOUDS THIS EVENING. A
WEAK FRONT OFF THE COAST WILL PUSH MVFR CIGS AGAINST THE COAST
THIS EVENING...AND POSSIBLY INTO THE INTERIOR AFTER 09Z. BEST
THREAT OF INLAND MVFR WILL BE S OF A KHIO TO KUAO LINE. NOT MUCH
CHANGE THROUGH DAY ON TUE...WITH PLENTY OF LOW TO MID VFR
CLOUDS...WITH AREAS OF MVFR CIGS THROUGH 18Z.

KPDX AND APPROACHES...VFR TONIGHT WITH CIGS LOWERING FROM 7K TO
NEAR 4K BY LATE TONIGHT. LIGHT TO MODERATE E WINDS CONTINUE
TONIGHT THEN EASE A BIT AFTER 15Z TUE.ROCKEY.

&&

.MARINE...A SERIES OF WEAK SYSTEMS WILL AFFECT THE WATERS FOR THE
NEXT SEVERAL DAYS. AS FIRST FRONT MOVES INTO THE REGION...WILL
HAVE SOUTH GUSTS 20 TO 25 KT TONIGHT ACROSS OUTER WATERS...THEN
WINDS EASE TUE AM.

SEAS GENERALLY 13 TO 16 FT THIS EVENING. WILL SEE A VERY VERY
SLOW DECREASE IN SEAS LATER TONIGHT INTO TUE AM...WITH SEAS 10 TO
12 TUE AM INTO EARLY TUE AFTERNOON. STILL THINK SEAS DROP BACK
UNDER 10 FT LATE TUE AFTERNOON OR EARLY EVENING.

NEXT ORGANIZED FRONT ARRIVES LATE THU INTO FRI. STRONG POTENTIAL
FOR GALE FORCE SOUTHERLY WINDS AT THAT TIME...WITH SEAS GETTING
BACK UP INTO THE 15 TO 20 FT RANGE.      ROCKEY.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON TUESDAY FOR THE
       OUTER WATERS...OR FROM CAPE SHOALWATER TO FLORENCE AND
       FROM 10 TO 60 MILES OFFSHORE.
    SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM TUE
       ON ALL WATERS.
    SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
       AND AGAIN FROM 10 AM TO 2 PM TUE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.




000
FXUS66 KPQR 160439
AFDPQR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PORTLAND OR
838 PM PST MON DEC 15 2014

.SYNOPSIS...A SERIES OF WEAK FRONTAL SYSTEMS CONTINUES TO MOVE
ONSHORE...WITH THE LATEST PIVOTING THROUGH WESTERN OREGON THIS
EVENING. HIGH PRESSURE REMAINS EAST OF THE CASCADES...PRODUCING
LOW-LEVEL OFFSHORE FLOW AND KEEPING THE AIR MASS DRY ENOUGH SO ONLY A
FEW LIGHT RAIN SHOWERS ARE ABLE TO REACH THE SURFACE. THIS PATTERN
WILL PREVAIL THROUGH MIDWEEK...THEN A STRONGER FRONT WILL BRING A
MORE SOLID SHOT OF RAIN TO THE AREA THURSDAY NIGHT. LOWERING SNOW
LEVELS SHOULD BRING SOME ACCUMULATING SNOW TO THE CASCADES FRIDAY AND
SATURDAY. HOWEVER...RISING SNOW LEVELS AND SUBTROPICAL MOISTURE
SPILLING INTO THE REGION WILL LIKELY BRING RAIN TO ALL BUT THE
HIGHEST PEAKS LATE IN THE WEEKEND AND EARLY NEXT WEEK.

&&

.EVENING UPDATE...VERY LITTLE IN THE WAY OF CHANGE TO THE AFTERNOON
FORECAST PACKAGE THIS EVENING...AS FORECAST APPEARS TO BE SOLIDLY ON
TRACK. RADAR SHOWS LITTLE IN THE WAY OF MOISTURE ASSOCIATED WITH THE
LATEST WEAK FRONTAL SYSTEM PIVOTING THROUGH WESTERN OREGON.
ASSOCIATED FORCING IS WEAK WITH ONLY WEAK LOW TO MID-LEVEL
FRONTOGENESIS AND MEAGER JET DYNAMICS. THUS WE EXPECT ONLY A FEW
PERIODS OF LIGHT RAIN...OR POSSIBLY JUST SPRINKLES IN SOME AREAS AS
THE AIR MASS HAS BEEN DRIED OUT BY LOW-LEVEL OFFSHORE FLOW.
TEMPERATURES HAVE LOWERED TO 32-35 DEG F IN THE UPPER PORTIONS OF THE
HOOD RIVER VALLEY...WHERE SOME LIGHT SNOW ACCUMULATIONS UP TO AN INCH
OR SO ARE POSSIBLE THROUGH TUESDAY MORNING.

KTTD-KDLS GRADIENTS HAVE DECREASED IN MAGNITUDE...-5.8 MB AS OPPOSED
TO THE -7.2 MB WHICH RESULTED IN LAST NIGHTS GUSTY EASTERLY FLOW.
GRADIENTS SHOULD CONTINUE TO SLOWLY SLACKEN OVER THE NEXT COUPLE
DAYS...AS HIGH PRESSURE SLOWLY WEAKENS EAST OF THE CASCADES. THERE
COULD BE BRIEF VARIATIONS IN THIS TREND...BUT OVERALL EXPECT EAST
WINDS TO BE SLOWLY RAMPING DOWN THE NEXT COUPLE DAYS. EAST WINDS MAY
PICK UP AGAIN THROUGH THE GORGE THU/THU NIGHT AS A STRONGER PACIFIC
FRONTAL SYSTEM APPROACHES THE COAST. THIS SYSTEM WILL BRING A BETTER
SHOT OF RAIN AND GUSTY SOUTH WINDS ALONG THE COAST AS WELL.  WEAGLE

.SHORT TERM...TONIGHT THROUGH THURSDAY...A COMPOSITE OF SATELLITE AND
RADAR IMAGERY SHOWS AN ELONGATED UPPER LEVEL TROUGH SLOWLY SLIDING
EASTWARD INTO THE PACIFIC NORTHWEST. OFF AND ON LIGHT RAIN HAS BEEN
OBSERVED ALONG THE COAST AND ACROSS THE SOUTHERN HALF OF THE
WILLAMETTE VALLEY TODAY. HOWEVER...QPF HAS BEEN MEAGER THUS FAR.
EXPECT THIS TREND TO CONTINUE...BUT AS THE UPPER LEVEL TROUGH AXIS
NUDGES EASTWARD...EXPECT LIGHT RAIN TO INCREASE ACROSS THE REST OF
NORTHWEST OREGON AND SOUTHWEST WASHINGTON OVERNIGHT AS THE LOWER
ATMOSPHERE MOISTENS A BIT.

THE NAM CONTINUES TO SUGGEST HEAVIER QPF WILL FALL ACROSS THE CENTRAL
COLUMBIA RIVER GORGE AND UPPER HOOD RIVER VALLEY OVERNIGHT...LIKELY
DUE TO A COMBINATION OF A WARM ADVECTION ALOFT AND LOW LEVEL UPSLOPE
FLOW INTO THE EAST SLOPES OF THE CASCADES. HOWEVER...AFTER
INVESTIGATING THE SREF ENSEMBLE MEMBERS...THE OPERATIONAL NAM IS THE
OUTLIER IN TERMS OF QPF VALUES FOR KDLS. AS A RESULT...QPF VALUES
WERE TRENDED TOWARDS THE SREF MEAN FOR THE CENTRAL COLUMBIA RIVER
GORGE AND UPPER HOOD RIVER VALLEY. GIVEN THE LOW LEVEL STRATUS IN
PLACE ACROSS THE COLUMBIA RIVER BASIN...DO NOT EXPECT TEMPERATURES
TO DROP DRAMATICALLY OVERNIGHT FROM THEIR CURRENT READINGS AROUND
HOOD RIVER AND PARKDALE. AS A RESULT...ANY PRECIPITATION SHOULD FALL
AS EITHER A COLD RAIN OR A RAIN/SNOW MIX AROUND HOOD RIVER AND AS
WET SNOW IN THE UPPER HOOD RIVER VALLEY. THUS...AN INCH OR TWO OF
SNOW APPEARS POSSIBLE ABOVE 1000 TO 1500 FT TONIGHT AROUND THE
CENTRAL COLUMBIA RIVER GORGE...BUT SUSPECT AMOUNTS APPROACHING THESE
NUMBERS COULD BE HARD TO COME BY EVEN IN THE UPPER HOOD RIVER VALLEY
BASED ON CURRENT TEMPERATURES AND MOST SREF QPF VALUES.

AN AREA OF ENHANCED CLOUD TOPS CURRENTLY NEAR 135W DUE WEST OF OREGON
WILL CONTINUE TO SPREAD EASTWARD TOWARDS THE COAST. MODELS ARE IN
REASONABLE AGREEMENT A SURFACE LOW PRESSURE WILL INTENSIFY OVERNIGHT
AND TUESDAY AS IT MOVES TOWARDS THE NORTHERN CALIFORNIA AND SOUTH
OREGON COAST. THIS SHOULD REINFORCE OFFSHORE LOW LEVEL FLOW AND TURN
OUR FLOW ALOFT A TOUCH MORE SOUTHERLY...WHICH SHOULD REDUCE SHOWER
ACTIVITY ON TUESDAY...PARTICULARLY DURING THE AFTERNOON AND EVENING
HOURS.

THE UPPER LEVEL TROUGH AXIS STILL LOOKS TO SWING THROUGH LATE
TUESDAY NIGHT INTO WEDNESDAY...PROBABLY BRINGING AN UPTICK IN SHOWER
ACTIVITY DURING THIS PERIOD. NOT ALL MODELS ARE ON BOARD WITH THIS
SCENARIO SO POPS WERE STILL KEPT IN THE HIGH END CHANCE TO LOW END
LIKELY RANGE FOR THIS TIME PERIOD...BUT SYNOPTICALLY THIS IDEA SEEMS
REASONABLE.

EVEN THOUGH SHORTWAVE RIDGING WILL BE PUSHING INTO THE REGION LATE
WEDNESDAY INTO EARLY THURSDAY...THE EC/SREF SUGGEST A WARM FRONT AND
LIGHT RAIN WILL PUSH INTO THE REGION ON THURSDAY...REDUCING THE
LENGTH OF OUR DRY WEATHER WINDOW. GIVEN THE GFS AND NAM KEEP US
RELATIVELY DRY DURING THIS PERIOD...POPS WERE HELD MAINLY IN THE
CHANCE RANGE FOR NOW ON THURSDAY. /NEUMAN


.LONG TERM...THURSDAY NIGHT THROUGH MONDAY...MODELS ARE IN GOOD
AGREEMENT A RELATIVELY STRONG FRONT WILL BRING A SOLID SHOT OF RAIN
TO THE AREA THURSDAY NIGHT INTO EARLY FRIDAY. FORTUNATELY...THIS WILL
BE FAIRLY TRANSIENT STORM SYSTEM SO HYDRO CONCERNS ARE LOW.

A COLD AIR UNSTABLE AIRMASS WILL FOLLOW AND KEEP SHOWERS GOING INTO
FRIDAY. SNOW LEVELS SHOULD LOWER TO NEAR 4000 FT ON FRIDAY SO
ACCUMULATING SNOW APPEARS LIKELY FOR AT LEAST THE HIGHER PASSES. AN
ADDITIONAL SHORTWAVE TROUGH OR TWO COULD ENHANCE SHOWER ACTIVITY
EARLY IN THE WEEKEND AND BRING MUCH NEEDED SNOW TO THE HIGHER
CASCADES.

MODELS GENERALLY AGREE SNOW LEVELS WILL RISE LATE IN THE WEEKEND AS A
WARM FRONT SLIDES INTO THE REGION. STRONG ZONAL FLOW WILL FOCUS
PERSISTENT AND HEAVIER RAIN ACROSS SOUTHWEST BRITISH COLUMBIA AND
WESTERN WASHINGTON LATE IN THE WEEKEND AND EARLY NEXT WEEK. FOR
NOW...IT APPEARS THE BULK OF THE HEAVIEST RAIN WILL REMAIN NORTH OF
OUR REGION...AND WHEN HEAVIER PRECIPITATION ARRIVES...IT WILL REMAIN
TRANSIENT ENOUGH ACROSS OUR FORECAST AREA TO MINIMIZE FLOOD
CONCERNS. NONETHELESS...THIS PATTERN CERTAINLY BEARS
WATCHING...PARTICULARLY ACROSS THE NORTHERN HALF OF THE FORECAST
AREA WHERE A SLIGHT SHIFT IN THE STORM TRACK COULD PUT US IN THE
PATH OF A MODEST FIRE HOSE AND FLOOD CONCERNS WILL RISE. /NEUMAN


&&


.AVIATION...VFR WITH INCREASING MID LEVEL CLOUDS THIS EVENING. A
WEAK FRONT OFF THE COAST WILL PUSH MVFR CIGS AGAINST THE COAST
THIS EVENING...AND POSSIBLY INTO THE INTERIOR AFTER 09Z. BEST
THREAT OF INLAND MVFR WILL BE S OF A KHIO TO KUAO LINE. NOT MUCH
CHANGE THROUGH DAY ON TUE...WITH PLENTY OF LOW TO MID VFR
CLOUDS...WITH AREAS OF MVFR CIGS THROUGH 18Z.

KPDX AND APPROACHES...VFR TONIGHT WITH CIGS LOWERING FROM 7K TO
NEAR 4K BY LATE TONIGHT. LIGHT TO MODERATE E WINDS CONTINUE
TONIGHT THEN EASE A BIT AFTER 15Z TUE.ROCKEY.

&&

.MARINE...A SERIES OF WEAK SYSTEMS WILL AFFECT THE WATERS FOR THE
NEXT SEVERAL DAYS. AS FIRST FRONT MOVES INTO THE REGION...WILL
HAVE SOUTH GUSTS 20 TO 25 KT TONIGHT ACROSS OUTER WATERS...THEN
WINDS EASE TUE AM.

SEAS GENERALLY 13 TO 16 FT THIS EVENING. WILL SEE A VERY VERY
SLOW DECREASE IN SEAS LATER TONIGHT INTO TUE AM...WITH SEAS 10 TO
12 TUE AM INTO EARLY TUE AFTERNOON. STILL THINK SEAS DROP BACK
UNDER 10 FT LATE TUE AFTERNOON OR EARLY EVENING.

NEXT ORGANIZED FRONT ARRIVES LATE THU INTO FRI. STRONG POTENTIAL
FOR GALE FORCE SOUTHERLY WINDS AT THAT TIME...WITH SEAS GETTING
BACK UP INTO THE 15 TO 20 FT RANGE.      ROCKEY.

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
PZ...SMALL CRAFT ADVISORY FOR WINDS UNTIL NOON TUESDAY FOR THE
       OUTER WATERS...OR FROM CAPE SHOALWATER TO FLORENCE AND
       FROM 10 TO 60 MILES OFFSHORE.
    SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 6 PM TUE
       ON ALL WATERS.
    SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR TONIGHT
       AND AGAIN FROM 10 AM TO 2 PM TUE.

&&

$$

INTERACT WITH US VIA SOCIAL MEDIA
WWW.FACEBOOK.COM/NWSPORTLAND
WWW.TWITTER.COM/NWSPORTLAND

THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON
FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS
COMMONLY REFERRED TO AS THE FORECAST AREA.



000
FXUS66 KMFR 160428
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
828 PM PST MON DEC 15 2014

.UPDATE...NUMEROUS UPDATES WERE NEEDED THIS EVENING. SOME CHANGES
WERE NEEDED IN THE NEAR TERM TO ACCOUNT FOR OBSERVED PRECIPITATION
OVER NORTHERN CALIFORNIA AND PORTIONS OF THE SISKIYOUS AND
CASCADES OF OREGON. WHILE NOT A SIGNIFICANT CHANGE, AS MUCH AS AN
INCH OF SNOW HAS BEEN ADDED TO SOME AREAS. OVERALL, SNOW AMOUNTS
ARE EXPECTED TO REMAIN BELOW 3 INCHES IN ALL BUT THE HIGHEST
ELEVATIONS, SO A WINTER WEATHER ADVISORY DOES NOT APPEAR TO BE
NEEDED. IN SUPPORT OF THIS LINE OF THOUGHT, TRAFFIC CAMERAS ALONG
INTERSTATE 5 NEAR MT SHASTA CITY SHOW WET ROADS, AND ALTHOUGH SOME
SNOW IS FALLING, THERE APPEARS TO BE NO ACCUMULATION ON THE ROAD
SURFACES.

THAT BEING SAID, THE SITUATION WILL BE MONITORED OVER THE NEXT
SEVERAL HOURS, AS UPSLOPING IN THE AREA OF MT SHASTA COULD RESULT
IN HEAVIER PRECIPITATION AND LOWERING SNOW LEVELS. FOR MORE
INFORMATION REGARDING THIS AND THE REST OF THE FORECAST TERM,
LEASE SEE THE PREVIOUS DISCUSSION BELOW. -BPN

&&

.AVIATION...BASED ON THE 15/00Z TAF CYCLE...A MIX OF VFR AND MVFR
CEILINGS CONTINUE ACROSS SOUTHERN OREGON AND NORTHERN CALIFORNIA AS
A FRONT MOVES THROUGH THIS EVENING. AREAS MVFR CIGS AND VISIBILITIES
ARE MAINLY ACROSS NORTHERN CALIFORNIA EARLY THIS EVENING BUT ARE
EXPECTED TO SPREAD INTO AREAS EAST OF THE CASCADES DURING THE
EVENING AS SNOW SHOWERS BECOMES PREVALENT. WEST OF THE CASCADES AND
ALONG THE COAST, EXPECT VALLEY MVFR CIGS/VIS AND COASTAL MVFR TO
DEVELOP AFTER MIDNIGHT WITH AREAS OF IFR CIGS/VIS DEVELOPING IN
WESTERN VALLEYS LATE TONIGHT INTO TUESDAY MORNING. LOW CIGS AND VIS
IS EXPECTED TO CLEAR TO VFR AROUND 19Z TUESDAY...BUT ISOLATED
MVFR/IFR MAY CONTINUE IN A FEW AREAS, PRIMARILY NEAR MOUNT SHASTA
CITY WHERE UPSLOPE CONDITIONS WILL BRING LINGERING CLOUDS AND
PRECIPITATION. /CC


&&

.MARINE...UPDATED 800 PM PST MON DEC 15 2014...MODERATE SOUTH
WINDS WILL DECREASE THROUGH EARLY TONIGHT. HOWEVER, STEEP SEAS
WILL CONTINUE THROUGH TONIGHT DUE TO LONG PERIOD 12 TO 15 FT WEST
SWELL AT 16 SECONDS AND RESIDUAL CHOPPY SEAS. SEAS WILL
TRANSITION TO SWELL DOMINATED TONIGHT AND TUESDAY MORNING AS WIND
SEAS LOWER BUT WILL REMAIN STEEP ABOVE 10 FEET.

ANOTHER LOW PRESSURE SYSTEM WILL ARRIVE TUESDAY WITH WINDS AND
SEAS LIKELY TO INCREASE AGAIN, MAINLY FOR THE OUTER COASTAL
WATERS. THIS LOW IS EXPECTED TO BRING SMALL CRAFT CONDITIONS TO
THE OUTER WATERS TUESDAY AFTERNOON AND EVENING AND GUSTS MAY REACH
OCCASIONAL GALE FORCE OVER THE WATERS BEYOND 20 NM SOUTH OF CAPE
BLANCO. DUE TO MODEL VARIABILITY WITH THE TRACK AND STRENGTH OF
THIS SYSTEM, CONFIDENCE IS HIGH FOR CONDITIONS REACHING SMALL
CRAFT FOR PORTIONS OF THE OUTER COASTAL WATERS BUT LOW TO MODERATE
IN GALE OR HAZARDOUS SEAS WARNING CONDITIONS DEVELOPING TUESDAY
AFTERNOON AND EVENING.

ON WEDNESDAY, A BRIEF PERIOD OF HIGH PRESSURE IS EXPECTED OVER THE
WATERS. THEN A MODERATE TO STRONG FRONT MOVES INTO THE WATERS
THURSDAY BRINGING THE POTENTIAL FOR HIGH END SMALL CRAFT WINDS OR
GALES. THEN FRIDAY INTO SATURDAY...LARGE LONG PERIOD SWELL IS
EXPECTED TO BUILD INTO THE WATERS AND MAY REACH 20 FT WITH A
DOMINANT PERIOD AROUND 19 SECONDS. THIS SWELL WOULD STIR THE
SEABED TO DEPTHS OF 800 FEET OR MORE, AND MAY CAUSE DAMAGE TO
FISHING EQUIPMENT AT SEA. ALSO, RESULTING VERY HEAVY SURF WOULD
MAKE BAR PASSAGE DANGEROUS TO NEARLY IMPOSSIBLE. -BPN/CC


&&

.PREV DISCUSSION... /ISSUED 544 PM PST MON DEC 15 2014/

SHORT TERM...SOUTHEAST WINDS INTO THE ROGUE VALLEY HAVE KEPT
PRECIPITATION FROM REACHING THE GROUND IN MEDFORD. RADAR HOWEVER
SHOWS UPSLOPE SHOWERS PUSHING AGAINST THE SOUTH SLOPE OF THE
SISKIYOUS. MOREOVER THE RADAR IS ALSO SHOWING PLENTY OF RETURNS
ACROSS NORTHERN HALF OF JACKSON COUNTY INTO THE UMPQUA DIVIDE.
OTHER AREAS REPORTING RAIN ARE WESTERN SISKIYOU COUNTY AND THE
MOUNT SHASTA AREA WHERE SOUTH TO SOUTHEAST WINDS ARE PROVIDING
UPSLOPE OROGRAPHIC FLOW.

SHORT TERM MODELS CONTINUE BRINGING MODERATE SOUTHEAST WINDS INTO
THE FORECAST AREA OVERNIGHT WITH LITTLE CHANGE IN WIND DIRECTION
IN THE SURFACE TO 850MB LAYER. AS A RESULT HAVE BACKED OFF ON
RAINFALL AMOUNT AND POPS TONIGHT AND HIGHLIGHTED FAVORED AREAS
WHERE UPSLOPE FLOW COMES INTO PLAY.

THE LOW PRESSURE AND TROUGH THAT WAS OFF THE COAST OF SOUTHERN
OREGON THIS MORNING IS FORECAST TO WEAKEN AND MOVE INLAND, TO BE
REINFORCED BY ANOTHER LOW PRESSURE ON TUESDAY. THIS LOW PRESSURE
APPEARS DEEPER THAN THE ONE THIS MORNING. WITH A STRONGER
NORTHERLY 120KT JET SUPPORT...THE LOW IS EXPECTED TO DIVE MORE TO
THE SOUTH THEN MOVE INLAND JUST SOUTH OF OUR FORECAST AREA TUESDAY
NIGHT. THE TRAJECTORY OF THIS LOW IS LIKELY TO GENERATE STRONG
UPSLOPE PRECIPITATION INTO MOUNT SHASTA TUESDAY NIGHT AND
WEDNESDAY. SNOW LEVELS WILL BE BETWEEN 4-4500 FEET BUT HEAVIER
PRECIPITATION RATE MAY BRING SNOW LEVELS IN THE MOUNT SHASTA AREA
TO JUST BELOW 4000 FEET. EXPECT SHOWERS TO LINGER INTO WEDNESDAY
AFTERNOON UNDER NORTHWEST FLOW. SOUTH END OF THE ROGUE VALLEY AND
THE DOUGLAS BASIN COULD SEE CLOUDY SKY AND PROLONGED PRECIPITATION
WEDNESDAY.

ON THURSDAY A RIDGE IS EXPECTED TO BRING WARMER AND DRIER CONDITION
TO OUR AREA BUT THE COAST MAY SEE PRECIPITATION APPROACHING IN THE
AFTERNOON IN THE FORM OF WARM FRONT OVERRUNNING. /FB

LONG TERM...FRIDAY THROUGH MONDAY...FRIDAY STARTS OFF WITH A COLD
FRONT REACHING THE COAST. EVERYTHING POINTS TO THIS STORM BEING A
MINOR TO MODERATE IMPACT EVENT...WITH MODERATE WINDS AFFECTING
MAINLY THE USUAL SUSPECTS...THE COAST...AND EAST SIDE...AND
POTENTIALLY THE SHASTA VALLEY. TEMPERATURES WARM SOME AHEAD OF THIS
FRONT...SO SNOW LEVELS SHOULD BE ABOVE 5000 FEET WHEN PRECIPITATION
STARTS. THIS FRONT DOESN`T HAVE A LOT OF JET ENERGY WITH IT...WITH
BASICALLY 60 KT AT 300MB...AND MOISTURE ISN`T THAT IMPRESSIVE SO
PRECIPITATION SHOULD NOT BE HEAVY. THAT SAID...MOUNTAIN PASSES WILL
LIKELY SEE ACCUMULATING SNOWS DURING THE DAY FRIDAY SO THE MANY
TRAVELERS ON THIS LAST-FRIDAY-BEFORE-CHRISTMAS SHOULD PLAN
ACCORDINGLY. INITIAL ANALOG GUIDANCE SUGGESTS HALF A FOOT OF SNOW IN
CRATER LAKE...AND RIGHT NOW IT LOOKS LIKE MAINLY A WET SNOW OR
RAIN/SNOW MIX ON SISKIYOU SUMMIT ALONG INTERSTATE 5 PER FORECAST
SNOW LEVELS.

FROM SATURDAY THROUGH MONDAY...IT LOOKS LIKE A "DIRTY RIDGE" WILL
SET UP WHICH BASICALLY MEANS PLENTY OF HIGH CLOUDS...GRADUALLY
WARMING CONDITIONS IN THE MOUNTAINS...INCREASED CHANCES OF VALLEY
FOG. ADDITIONALLY...SOME WARM FRONTAL PRECIPITATION RIDING OVER THE
RIDGE WILL BRING CHANCES OF PRECIPITATION MAINLY TO THE UMPQUA BASIN
AND COAST NORTH OF CAPE BLANCO. BOTH THE ECMWF AND GFS SUGGEST THE
BEST CHANCE OF THIS WARM FRONTAL PRECIPITATION WILL BE SATURDAY
NIGHT INTO SUNDAY.

LOOKING FURTHER OUT...TO CHRISTMAS EVE...THE GFS SUGGESTS A COLD
TROUGH MOVING THROUGH FROM THE NORTHWEST WHICH WOULD BRING SOME
SNOWFALL TO ELEVATIONS 3000 FEET AND ABOVE...WHEREAS THE ECMWF
KEEPS MORE OF THE DIRTY RIDGE SOLUTION THAT ALLOWS MOISTURE TO
INTRUDE. LOOKING AT THE NAEFS MODEL THERE IS A WIDE SPREAD OF
SOLUTIONS IN THE ENSEMBLE MEMBERS FOR A CHRISTMAS EVE TROUGH. IN
SUMMARY...IT`S TOO EARLY TO TELL WHAT`S GOING TO HAPPEN CHRISTMAS
EVE BUT STAY TUNED. /NSK

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM PST THIS EVENING FOR
     PZZ350-356-370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 AM PST TUESDAY
     FOR PZZ350-356.
     SMALL CRAFT ADVISORY FOR WINDS FROM 10 AM TO 10 PM PST TUESDAY
     FOR PZZ370-376.
     SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS UNTIL 10 PM PST TUESDAY
     FOR PZZ370-376.

$$

BPN/CC/FJB/NSK




    US Dept of Commerce
    National Oceanic and Atmospheric Administration
    National Weather Service
    1325 East West Highway
    Silver Spring, MD 20910
    Page Author: NWS Internet Services Team
Disclaimer
Information Quality
Credits
Glossary
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities