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000
AGUS76 KRSA 201701
HMDRSA

HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE / CALIFORNIA
NEVADA RFC / SACRAMENTO CA 955 AM PDT MON OCT 20 2014

***** REISSUANCE TO MODIFY HYROLOGICAL DISCUSSION *****

...COLD FRONT MOVING THRU NORTHERN HALF OF REGION TODAY INTO TUE...
...MODERATE TO HEAVY PRECIP NORTH OF I-80 LATTER HALF OF THE WEEK...

.24 HOUR PRECIPITATION TOTALS (ENDING OCT 20 AT 500 AM PDT)...

PRECIP BEGAN FALLING SHORTLY BEFORE MIDNIGHT LAST NIGHT ON THE NORTH
COAST AS A FRONT MOVED INTO THE AREA AHEAD OF AN UPPER TROUGH
CURRENTLY CENTERED OVER 130W. PRECIP AMOUNTS WERE HIGHEST OVER THE
NW CORNER OF THE STATE IN THE SMITH BASIN...WHERE 1-2" FELL PRIOR TO
5 AM THIS MORNING. AMOUNTS FELL TO AROUND 0.3-0.6" OVER THE EEL R
BASIN...AS WELL AS EAST OF THE SMITH INTO THE TRINITY MTNS. LESS
THAN 0.1" HAD ACCUMULATED IN THE RUSSIAN R BASIN PRIOR TO 5 AM.
FURTHER NORTH AND INLAND OVER THE UPPER KLAMATH...0.2-0.4" PRECIP
FELL ALONG THE WEST SLOPES OF THE SRN OREGON CASCADES...WITH NOTHING
BREACHING THE CREST THUS FAR.


.METEOROLOGICAL CONDITIONS (SHORT TERM: MON AM - THU AM)...

WV/IR IMAGERY SHOWS THE NEXT S/WV TROF MOVING WITHIN 130W WHILE THE
ASSOCIATED COLD FRONT IS MOVING ONSHORE ALONG THE NORTH COAST THIS
MORNING. PRECIP SHIELD AHEAD OF THE FRONTAL BOUNDARY IS FAIRLY
NARROW WITH THE LEADING EDGE STRETCHING FROM THE CREST OF THE
SOUTHERN OREGON CASCADES SOUTH ACROSS THE SHASTA LAKE DRAINAGE AND
ALONG THE COASTAL MOUNTAINS BEFORE MOVING OFFSHORE NEAR THE GOLDEN
GATE. THERE IS A DECENT AMOUNT OF MOISTURE ENTRAINED INTO THE SYSTEM
CONVERGING JUST AHEAD OF THE COLD FRONT. GPS-MET SENSORS ALONG THE
NORTH COAST SHOWED IPW VALUES PEAKING AROUND 1.25-INCH. BLENDED TPW
IMAGERY SHOWS THE MOISTURE PLUME MOVING ONSHORE ALONG THE NORTH
COAST WITH THE COLD FRONT AND THEN TRAILING OFF TOWARD THE SW BACK
TO THE LOWER LATITUDES.

THROUGH THE REST OF THE MORNING INTO THE AFTERNOON HOURS...LOOK FOR
THE COLD FRONT TO PROGRESS SOUTH AND INLAND TO THE SIERRA BACK
THROUGH THE SF BAY AREA. MEANWHILE...THE S/WV TROF AXIS WILL ARRIVE
AT THE COAST AROUND 21/00Z. THE MAJORITY OF THE PRECIP WILL FALL
WITH THE FRONTAL BAND...BUT THE MODELS INDICATE LIGHT PRECIP WITH
THE COOLER AIR ALOFT NEAR THE S/WV TROF. OVERNIGHT...PRECIP WILL
SHIFT TO NORTHERN NEVADA...BUT HERE THE PRECIP WILL BE MORE
ASSOCIATED WITH THE S/WV TROF MOVING THROUGH THE AREA. BY LATER
TUESDAY MORNING INTO THE AFTERNOON HOURS...THE S/WV TROF WILL EXIT
THE AREA TO THE NE ON ITS WAY TO THE NORTHERN ROCKIES.

FOR LATER TUESDAY INTO WEDNESDAY...THE FLOW ALOFT TURNS WESTERLY
ACROSS THE PACIFIC AT THE MID-LATITUDES. WITH A DEEP VORTEX OVER THE
GULF OF ALASKA AND A SUBTROPICAL HIGH PRESSURE RIDGE CENTERED JUST
EAST OF THE HAWAIIAN ISLANDS...THE UPR JET WILL STRENGTHEN ALONG 40N
WITH WINDS AT THE 300-MB LEVEL REACHING NEAR 155-KT ACCORDING TO THE
LATEST EC (20/00Z) AND GFS (20/06Z). A MOISTURE PLUME WILL RIDE EAST
ALONG THIS FLOW AT 40N...AFTER ADVECTING NORTH FROM THE LOWER
LATITUDES NEAR AND JUST WEST OF THE INT/L DATELINE. FOR
WEDNESDAY...THE MODELS ARE IN RELATIVELY GOOD AGREEMENT INITIALLY
TAKING THE MOISTURE PLUME INTO THE PACNW BEFORE SINKING SOUTH AND
AFFECTING THE UPPER KLAMATH RIVER BASIN AND FAR NW CA. WITH BETTER
AGREEMENT ON DAY 3...CONFIDENCE IS BETTER WITH THE MODERATE TO HEAVY
PRECIP AMOUNTS...ESPECIALLY THE SECOND HALF OF THE DAY. WINDS AT THE
850-MB LEVEL ARE SWLY IN THE 40- TO 50-KT RANGE WITH PW VALUES NEAR
1.50-INCHES INTERSECTING THE COAST. ISENTROPIC LIFT AHEAD OF THE
BAROCLINIC ZONE LOOKS MOST IDEAL BETWEEN THE 305- AND 310-K
SURFACES...WHILE CONDENSATION PRESSURE DEFICITS EASILY DROP UNDER 10-
MB. THE 12-HOUR PERIOD ENDING THURSDAY MORNING (23/12Z) WILL BE
WETTEST OVER THE SMITH RIVER BASIN WITH 1.50- TO ALMOST 3.00-INCHES
POSSIBLE.


.METEOROLOGICAL CONDITIONS (LONG TERM: THU AM - SUN AM)...

THE FRONT IS EXPECTED TO CONTINUE MOVING THROUGH NORTHERN CA
THURSDAY MORNING...BRINGING MODERATE TO HEAVY PRECIP TO MUCH OF
COASTAL NORTHERN CA THROUGH THE DAY. MODELS DROP THE FRONT AS FAR
SOUTH AS THE RUSSIAN BASIN AND NORTHEAST THROUGH THE SACRAMENTO
VALLEY INTO THE NORTHERN SIERRA AND THE NW CORNER OF NEVADA BY
AFTERNOON. AFTER THIS POINT...SIGNIFICANT DIFFERENCES ARISE BETWEEN
THE GFS...EC...AND GEM MODELS THROUGH THE REMAINDER OF THE PERIOD.

TIMING...TRACK...AND INTENSITY ALL FALL OUT OF AGREEMENT FOR THE
LAST DAY AND A HALF OF THE FORECAST PERIOD. THE 20/06Z GFS
STRENGTHENS AND STALLS THE FRONT OUT OVER SONOMA AND MENDOCINO
COUNTIES THURSDAY NIGHT INTO FRIDAY...BRINGING A PROLONGED PERIOD OF
HEAVY PRECIP TO THE AREA. MEANWHILE...A SECOND WAVE OF PRECIP
DEVELOPS JUST AHEAD OF THE TROUGH...BRINGING MODERATE PRECIP TO THE
NORTH COAST FRIDAY NIGHT AND MOVING INTO THE REST OF NORTHERN CA
OVERNIGHT INTO SATURDAY MORNING. THE TROUGH FINALLY COMES ONSHORE
LATER IN THE DAY SATURDAY...BRINGING SCATTERED SHOWERS TO MUCH OF
THE NORTHERN HALF OF CA AND NRN NEVADA THROUGH SUNDAY NIGHT BEFORE
PUSHING EAST. THE 20/00Z ECMWF TAKES A MORE MODERATE APPROACH...
WASHING OUT THE FRONT ON THURSDAY THROUGH MENDOCINO COUNTY AND
DRYING OUT MUCH OF THE AREA BEFORE A SECOND WAVE MOVES IN FRIDAY
NIGHT. THIS SECOND WAVE IS MUCH MORE MODERATE THAN THE SECOND THE
GFS PULLS THROUGH...BUT DOES STILL COVER MUCH OF THE SAME AREA. A
THIRD AND FINAL WAVE QUICKLY PASSES THROUGH AS THE TROUGH MOVES INTO
NORTHERN CA SATURDAY NIGHT...AND MOVES EAST...AGAIN LEAVING THE
FORECAST AREA DRY BY SUNDAY MORNING. THE CANADIAN IS MOST SIMILAR TO
THE GFS...BUT BRINGS IN A MUCH HEAVIER FINAL WAVE TO THE NORTH COAST
SATURDAY NIGHT.

THE CURRENT FORECAST PACKAGE REFLECTS A BLEND OF THE COHESIVE GFS
AND EC MODELS THROUGH 00Z FRIDAY...THEN STEERS THE FORECAST IN THE
DIRECTION OF THE 20/00Z ECMWF FOR THE REMAINDER OF THE PERIOD. HAVE
TWEAKED SOME PRECIP AMOUNTS ABOVE THE MODEL GUIDANCE FOR THIS
PERIOD...AS IS TYPICALLY SEEN WITH SYSTEMS THAT FOLLOW THE EC.
EXPECT THE DETAILS TO CHANGE QUITE A BIT AS THE WEEK PROGRESSES AND
(HOPEFULLY) MODELS FIND A BETTER COMPROMISE.


.HYDROLOGICAL CONDITIONS...

VERY SMALL RISES TO NORTH COASTAL RIVERS AHD STREAMS ARE EXPECTED
FROM THE WEATHER SYSTEM CURRENTLY MOVING ACROSS NW CALIFORNIA.

COASTAL BASINS OF NORTHERN CALIFORNIA WILL SHOW THE MOST RESPONSE TO
PRECIPITATION FROM THE WEATHER SYSTEM ARRIVING BY WEDNESDAY...WITH
ONLY MINOR RISES EXPECTED...THE LARGEST OF THESE RISES WILL BE IN
THE SMITH RIVER BASIN.

ALL RIVER FORECAST POINTS ARE EXPECTED TO REMAIN BELOW MONITOR
LEVELS DURING THE NEXT SEVERAL DAYS.

MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

JM/DRK/JM/AT

$$





000
AGUS76 KRSA 201640
HMDRSA

HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE / CALIFORNIA
NEVADA RFC / SACRAMENTO CA 930 AM PDT MON OCT 20 2014

...COLD FRONT MOVING THRU NORTHERN HALF OF REGION TODAY INTO TUE...
...MODERATE TO HEAVY PRECIP NORTH OF I-80 LATTER HALF OF THE WEEK...

.24 HOUR PRECIPITATION TOTALS (ENDING OCT 20 AT 500 AM PDT)...

PRECIP BEGAN FALLING SHORTLY BEFORE MIDNIGHT LAST NIGHT ON THE NORTH
COAST AS A FRONT MOVED INTO THE AREA AHEAD OF AN UPPER TROUGH
CURRENTLY CENTERED OVER 130W. PRECIP AMOUNTS WERE HIGHEST OVER THE
NW CORNER OF THE STATE IN THE SMITH BASIN...WHERE 1-2" FELL PRIOR TO
5 AM THIS MORNING. AMOUNTS FELL TO AROUND 0.3-0.6" OVER THE EEL R
BASIN...AS WELL AS EAST OF THE SMITH INTO THE TRINITY MTNS. LESS
THAN 0.1" HAD ACCUMULATED IN THE RUSSIAN R BASIN PRIOR TO 5 AM.
FURTHER NORTH AND INLAND OVER THE UPPER KLAMATH...0.2-0.4" PRECIP
FELL ALONG THE WEST SLOPES OF THE SRN OREGON CASCADES...WITH NOTHING
BREACHING THE CREST THUS FAR.


.METEOROLOGICAL CONDITIONS (SHORT TERM: MON AM - THU AM)...

WV/IR IMAGERY SHOWS THE NEXT S/WV TROF MOVING WITHIN 130W WHILE THE
ASSOCIATED COLD FRONT IS MOVING ONSHORE ALONG THE NORTH COAST THIS
MORNING. PRECIP SHIELD AHEAD OF THE FRONTAL BOUNDARY IS FAIRLY
NARROW WITH THE LEADING EDGE STRETCHING FROM THE CREST OF THE
SOUTHERN OREGON CASCADES SOUTH ACROSS THE SHASTA LAKE DRAINAGE AND
ALONG THE COASTAL MOUNTAINS BEFORE MOVING OFFSHORE NEAR THE GOLDEN
GATE. THERE IS A DECENT AMOUNT OF MOISTURE ENTRAINED INTO THE SYSTEM
CONVERGING JUST AHEAD OF THE COLD FRONT. GPS-MET SENSORS ALONG THE
NORTH COAST SHOWED IPW VALUES PEAKING AROUND 1.25-INCH. BLENDED TPW
IMAGERY SHOWS THE MOISTURE PLUME MOVING ONSHORE ALONG THE NORTH
COAST WITH THE COLD FRONT AND THEN TRAILING OFF TOWARD THE SW BACK
TO THE LOWER LATITUDES.

THROUGH THE REST OF THE MORNING INTO THE AFTERNOON HOURS...LOOK FOR
THE COLD FRONT TO PROGRESS SOUTH AND INLAND TO THE SIERRA BACK
THROUGH THE SF BAY AREA. MEANWHILE...THE S/WV TROF AXIS WILL ARRIVE
AT THE COAST AROUND 21/00Z. THE MAJORITY OF THE PRECIP WILL FALL
WITH THE FRONTAL BAND...BUT THE MODELS INDICATE LIGHT PRECIP WITH
THE COOLER AIR ALOFT NEAR THE S/WV TROF. OVERNIGHT...PRECIP WILL
SHIFT TO NORTHERN NEVADA...BUT HERE THE PRECIP WILL BE MORE
ASSOCIATED WITH THE S/WV TROF MOVING THROUGH THE AREA. BY LATER
TUESDAY MORNING INTO THE AFTERNOON HOURS...THE S/WV TROF WILL EXIT
THE AREA TO THE NE ON ITS WAY TO THE NORTHERN ROCKIES.

FOR LATER TUESDAY INTO WEDNESDAY...THE FLOW ALOFT TURNS WESTERLY
ACROSS THE PACIFIC AT THE MID-LATITUDES. WITH A DEEP VORTEX OVER THE
GULF OF ALASKA AND A SUBTROPICAL HIGH PRESSURE RIDGE CENTERED JUST
EAST OF THE HAWAIIAN ISLANDS...THE UPR JET WILL STRENGTHEN ALONG 40N
WITH WINDS AT THE 300-MB LEVEL REACHING NEAR 155-KT ACCORDING TO THE
LATEST EC (20/00Z) AND GFS (20/06Z). A MOISTURE PLUME WILL RIDE EAST
ALONG THIS FLOW AT 40N...AFTER ADVECTING NORTH FROM THE LOWER
LATITUDES NEAR AND JUST WEST OF THE INT/L DATELINE. FOR
WEDNESDAY...THE MODELS ARE IN RELATIVELY GOOD AGREEMENT INITIALLY
TAKING THE MOISTURE PLUME INTO THE PACNW BEFORE SINKING SOUTH AND
AFFECTING THE UPPER KLAMATH RIVER BASIN AND FAR NW CA. WITH BETTER
AGREEMENT ON DAY 3...CONFIDENCE IS BETTER WITH THE MODERATE TO HEAVY
PRECIP AMOUNTS...ESPECIALLY THE SECOND HALF OF THE DAY. WINDS AT THE
850-MB LEVEL ARE SWLY IN THE 40- TO 50-KT RANGE WITH PW VALUES NEAR
1.50-INCHES INTERSECTING THE COAST. ISENTROPIC LIFT AHEAD OF THE
BAROCLINIC ZONE LOOKS MOST IDEAL BETWEEN THE 305- AND 310-K
SURFACES...WHILE CONDENSATION PRESSURE DEFICITS EASILY DROP UNDER 10-
MB. THE 12-HOUR PERIOD ENDING THURSDAY MORNING (23/12Z) WILL BE
WETTEST OVER THE SMITH RIVER BASIN WITH 1.50- TO ALMOST 3.00-INCHES
POSSIBLE.


.METEOROLOGICAL CONDITIONS (LONG TERM: THU AM - SUN AM)...

THE FRONT IS EXPECTED TO CONTINUE MOVING THROUGH NORTHERN CA
THURSDAY MORNING...BRINGING MODERATE TO HEAVY PRECIP TO MUCH OF
COASTAL NORTHERN CA THROUGH THE DAY. MODELS DROP THE FRONT AS FAR
SOUTH AS THE RUSSIAN BASIN AND NORTHEAST THROUGH THE SACRAMENTO
VALLEY INTO THE NORTHERN SIERRA AND THE NW CORNER OF NEVADA BY
AFTERNOON. AFTER THIS POINT...SIGNIFICANT DIFFERENCES ARISE BETWEEN
THE GFS...EC...AND GEM MODELS THROUGH THE REMAINDER OF THE PERIOD.

TIMING...TRACK...AND INTENSITY ALL FALL OUT OF AGREEMENT FOR THE
LAST DAY AND A HALF OF THE FORECAST PERIOD. THE 20/06Z GFS
STRENGTHENS AND STALLS THE FRONT OUT OVER SONOMA AND MENDOCINO
COUNTIES THURSDAY NIGHT INTO FRIDAY...BRINGING A PROLONGED PERIOD OF
HEAVY PRECIP TO THE AREA. MEANWHILE...A SECOND WAVE OF PRECIP
DEVELOPS JUST AHEAD OF THE TROUGH...BRINGING MODERATE PRECIP TO THE
NORTH COAST FRIDAY NIGHT AND MOVING INTO THE REST OF NORTHERN CA
OVERNIGHT INTO SATURDAY MORNING. THE TROUGH FINALLY COMES ONSHORE
LATER IN THE DAY SATURDAY...BRINGING SCATTERED SHOWERS TO MUCH OF
THE NORTHERN HALF OF CA AND NRN NEVADA THROUGH SUNDAY NIGHT BEFORE
PUSHING EAST. THE 20/00Z ECMWF TAKES A MORE MODERATE APPROACH...
WASHING OUT THE FRONT ON THURSDAY THROUGH MENDOCINO COUNTY AND
DRYING OUT MUCH OF THE AREA BEFORE A SECOND WAVE MOVES IN FRIDAY
NIGHT. THIS SECOND WAVE IS MUCH MORE MODERATE THAN THE SECOND THE
GFS PULLS THROUGH...BUT DOES STILL COVER MUCH OF THE SAME AREA. A
THIRD AND FINAL WAVE QUICKLY PASSES THROUGH AS THE TROUGH MOVES INTO
NORTHERN CA SATURDAY NIGHT...AND MOVES EAST...AGAIN LEAVING THE
FORECAST AREA DRY BY SUNDAY MORNING. THE CANADIAN IS MOST SIMILAR TO
THE GFS...BUT BRINGS IN A MUCH HEAVIER FINAL WAVE TO THE NORTH COAST
SATURDAY NIGHT.

THE CURRENT FORECAST PACKAGE REFLECTS A BLEND OF THE COHESIVE GFS
AND EC MODELS THROUGH 00Z FRIDAY...THEN STEERS THE FORECAST IN THE
DIRECTION OF THE 20/00Z ECMWF FOR THE REMAINDER OF THE PERIOD. HAVE
TWEAKED SOME PRECIP AMOUNTS ABOVE THE MODEL GUIDANCE FOR THIS
PERIOD...AS IS TYPICALLY SEEN WITH SYSTEMS THAT FOLLOW THE EC.
EXPECT THE DETAILS TO CHANGE QUITE A BIT AS THE WEEK PROGRESSES AND
(HOPEFULLY) MODELS FIND A BETTER COMPROMISE.


.HYDROLOGICAL CONDITIONS...

VERY SMALL RISES TO NORTH COASTAL RIVERS AHD STREAMS ARE EXPECTED
FROM THE WEATHER SYSTEM CURRENTLY MOVING ACROSS NW CALIFORNIA.

PRECIPITATION FROM THE WEATHER SYSTEM ARRIVING BY WEDNESDAY WILL
PRIMARILY AFFECT COASTAL DRAINAGES OF NORTHERN CALIFORNIA...WITH
ONLY MINOR RISES EXPECTED...THE LARGEST OF THSES RISES WILL BE
FOCUSED IN THE SMITH RIVER BASIN.

ALL RIVER FORECAST POINTS ARE EXPECTED TO REMAIN BELOW MONITOR
LEVELS DURING THE NEXT SEVERAL DAYS.

MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

JM/DRK/JM/AT

$$





000
AGUS76 KRSA 191554
HMDRSA

HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE / CALIFORNIA
NEVADA RFC / SACRAMENTO CA 855 AM PDT SUN OCT 19 2014

...PRECIP MOVES ACROSS THE NORTH LATE SUN THRU EARLY TUE...
...STATIONARY BAND OF PRECIP NEAR THE CA/ORE BORDER WED AND THU...

.24 HOUR PRECIPITATION TOTALS (ENDING OCT 19 AT 500 AM PDT)...

A FEW LIGHT SHOWERS LINGERED ACROSS THE NORTH COAST EARLY YESTERDAY
WITH AMOUNTS NEAR A FEW HUNDREDTHS AT BEST.


.METEOROLOGICAL CONDITIONS (SHORT TERM: SUN AM - SAT AM)...

LATEST SYNOPTIC PATTERN SHOWS AN UPR RIDGE ALIGNED OVER THE
INTERMOUNTAIN WEST NORTHWARD INTO WEST-CENTRAL CANADA. OFFSHORE AN
UPR TROF IS NOW CROSSING 140W. ALSO...A WEAK UPR LOW FROM THE
SPLITTING SYSTEM A FEW DAYS AGO STILL RESIDES JUST SOUTH OF THE
US/MEXICO BORDER...DRIFTING TO THE EAST.

THE NEXT OPPORTUNITY FOR PRECIP ACROSS THE REGION IS WITH THE
OFFSHORE UPR TROF CROSSING 140W. THE ASSOCIATED COLD FRONT IS MOVING
WITHIN 130W THIS MORNING. BLENDED TPW IMAGERY SHOWS A NARROW
MOISTURE PLUME CONVERGING AHEAD OF THE FRONTAL BOUNDARY WITH VALUES
GENERALLY IN THE RANGE OF 1.00- TO 1.25-INCHES. OVERALL TIMING OF
THE PRECIP BRINGS LIGHT PRECIP TO THE IMMEDIATE NORTH COAST FROM
CAPE MENDOCINO NORTHWARD EITHER LATE SUNDAY OR EARLY MONDAY.

PRECIP SPREADS SOUTH AND INLAND THROUGH MONDAY WITH PRECIP REACHING
SOUTH TO A SF BAY AREA TO YOSEMITE LINE. THE UPR TROF AXIS WILL
CROSS THE COAST MONDAY AFTERNOON. THERE ARE SOME SLIGHT
DISCREPANCIES AMONGST THE LATEST MODELS IN TERMS OF HOW DEEP THE
S/WV TROF WILL BE AS IT MOVES ACROSS CA. THE 19/00Z EC IS THE
SHALLOWEST...WHILE THE OTHER CAMP OF THE 19/00Z GEM...19/06Z NAM...
AND 19/06Z GFS ARE A BIT DEEPER. FOR NOW...FOLLOWED THE MAJORITY OF
THE MODELS...AND THIS RESULTS IN SLIGHTLY HIGHER TOTALS FOR THE
NORTHERN SIERRA. IF THE EC VERIFIES...PRECIP TOTALS WILL BE ON THE
LOWER END. ALSO...THE DEPTH OF THE SYSTEM WILL AFFECT PRECIP
COVERAGE AND AMOUNTS OVER THE NORTHERN PORTION OF NEVADA. THE DEEPER
SOLUTIONS DO GENERATE WIDESPREAD LIGHT PRECIP ACROSS THE NORTHERN
HALF OF THE STATE.

AFTER THIS S/WV TROF EXITS THE REGION...THE CONFIDENCE IN THE LONGER
RANGE BEGINS TO LOWER. THERE ARE DEFINITE DIFFERENCES IN HOW STRONG
THE UPR RIDGE BUILDS OVER THE 4-CORNERS REGION AND THE ALIGNMENT OF
THE NEXT UPR TROF OVER THE EASTERN PACIFIC. FOR WEDNESDAY...THE
MOISTURE PLUME WILL INTERSECT THE PACNW COAST WITH THE SOUTHERN
FRINGE AFFECTING THE UPPER KLAMATH AND FAR NW CORNER OF CA (MAINLY
THE SMITH AND LOWER KLAMATH RIVER BASINS). AS A RESULT...THE
HEAVIEST PRECIP WILL REMAIN NORTH OF THE REGION WITH LIGHTER AMOUNTS
CLIPPING THE REGION. INTO THURSDAY...THE EC NARROWS AND ERODES SOME
OF THE MOISTURE PLUME AS IT FOCUSES ON THE CA/ORE BORDER AREA. THIS
WOULD CONTINUE LIGHT PRECIP OVER THE AFOREMENTIONED AREAS.
HOWEVER...THE GFS IS MORE BULLISH IN KEEPING THE PLUME TOGETHER WITH
SOME MODERATE TO LOCALLY HEAVY PRECIP DEPICTED OVER THE NORTH COAST
FROM NEAR CAPE MENDOCINO NORTHWARD. WITH THESE DRAMATIC
DIFFERENCES...FOR NOW HAVE STUCK WITH A MORE CONSERVATIVE APPROACH
IN TERMS OF PRECIP AMOUNTS OFFERED UP BY THE EC.

AS THE WEEKEND APPROACHES...THE EC AND GFS CONTINUE THEIR
DIFFERENCES. THE EC IS STRONGER WITH THE UPR RIDGE CENTERED NEAR THE
4-CORNERS REGION WITH THE UPR TROF DEVELOPING OUT BETWEEN 140W AND
150W. THE GFS SHOWS A MORE POSITIVELY TILTED UPR RIDGE EXTENDING
FROM NW MEXICO TOWARD THE CENTRAL PLAINS AND WESTERN GREAT LAKES
STATES. AS A RESULT...THE EASTERN PACIFIC UPR TROF IS FARTHER
DOWNSTREAM (BETWEEN 130W AND 140W) WHEN COMPARED TO THE EC. FOR
NOW...FOLLOWED THE EC AGAIN...WHICH IS THE FAVORED SOLUTION AT THIS
TIME.


.HYDROLOGICAL CONDITIONS...

PRECIPITATON FROM THE WEATHER SYSTEM ARRIVING LATE TONIGHT/EARLY
TOMORROW IS EXPECTED TO PRODUCE ONLY SMALL RISES TO RIVERS AND
STREAMS IN THE NORTH COAST REGION.

ALL RIVER FORECAST POINTS ARE EXPECTED TO REMAIN BELOW MONITOR
LEVELS DURING THE NEXT SEVERAL DAYS.


MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

DRK/AT

$$





000
AGUS76 KRSA 181549
HMDRSA

HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE / CALIFORNIA
NEVADA RFC / SACRAMENTO CA 845 AM PDT SAT OCT 18 2014

...NEXT SYSTEM MOVES IN LATE SUNDAY INTO MONDAY...

.24 HOUR PRECIPITATION TOTALS (ENDING OCT 18 AT 500 AM PDT)...

A WEAKENING SYSTEM MOVED ACROSS THE YESTERDAY WITH PRECIP BEING
CONFINED TO THE UPPER KLAMATH RIVER BASIN AND COASTAL SECTIONS FROM
THE SMITH RIVER BASIN SOUTH TO THE RUSSIAN RIVER BASIN.

AMOUNTS IN THE UPPER KLAMATH RIVER BASIN WERE SCATTERED AND IN
GENERAL FROM A FEW HUNDREDTHS OF AN INCH TO 0.10-INCH. ALONG COASTAL
SECTIONS THE GREATEST AMOUNTS FELL BETWEEN CAPE MENDOCINO AND THE
SMITH RIVER BASIN. TOTALS IN THERE AREA WERE IN THE RANGE OF 0.25-
TO 0.50-INCH WITH A FEW AMOUNTS OVER THE KING RANGE NEAR CAPE
MENDOCINO REACHED AND SLIGHTLY SURPASSED THE 1.00-INCH MARK. SOUTH
ACROSS MENDOCINO AND SONOMA COUNTIES AMOUNTS TRAILED OFF FROM NORTH
TO SOUTH WITH TOTALS IN THE FAR NORTH NEAR 0.50-INCH AND 0.10-INCH
IN THE SOUTH.

OTHERWISE...THE REST OF THE REGION REMAINED DRY ON FRIDAY.


.METEOROLOGICAL CONDITIONS (SAT AM - FRI AM)...

AS EXPECTED...THE INCOMING SYSTEM YESTERDAY HAS SPLIT WITH THE MORE
PROGRESSIVE NORTHERN PIECE MOVING OFF TOWARD THE ENE AND NEAR THE
NORTHERN ROCKIES...WHILE THE SLOWER SOUTHERN PIECE IS FORMING A WEAK
UPR LOW OVER SOUTHERN CA. THERE ARE A FEW ECHOES STREAMING FROM
SOUTH TO NORTH ACROSS CLARK AND LINCOLN COUNTIES AHEAD OF THE UPR
LOW...BUT LOOKING AT THE 18/12Z KVEF RAOB...MUCH OF THE MOISTURE
RESIDES IN THE MID-LEVELS WITH A FAIRLY DRY SUB-CLOUD LAYER. NOT
EXPECTING ANY MEASURABLE PRECIP IN THIS AREA. ALSO...THERE ARE A FEW
LINGERING SHOWERS ALONG THE FAR NORTH COAST THIS MORNING. THIS
PRECIP IS EXPECTED TO WRAP UP DURING THE MORNING HOURS WITH A
POSITIVELY TILTED UPR RIDGE NUDGING OVER NORTHERN CA.

ATTENTION NEXT TURNS TO THE PARENT UPR LOW SPINNING OVER THE GULF OF
ALASKA NEAR 50N/147W AND THE ASSOCIATED UPR TROF CROSSING 150W. THIS
WILL BE THE NEXT OPPORTUNITY FOR PRECIP ACROSS THE NORTHERN PORTION
OF THE REGION. THERE ARE A FEW DISCREPANCIES AMONGST THE MODELS IN
TERMS OF THE STRENGTH OF THE S/WV TROF MOVING ACROSS THE REGION. THE
18/00Z GEM IS THE SHALLOWEST...THE 18/00Z AND 18/06Z GFS THE
DEEPEST...AND THE 18/00Z EC ALONG WITH THE 18/06Z NAM IN BETWEEN THE
TWO. AS A RESULT...THE GFS IS THE WETTEST WITH THE GEM THE DRIEST.
THE OTHER TWO ARE A GOOD COMPROMISE. ALSO...THE 18/09Z SREF LOOKS TO
BE A DECENT COMPROMISE AS WELL. A MIDDLE OF THE ROAD APPROACH WAS
TAKEN WITH THIS SYSTEM FOLLOWING WITH PRECIP AMOUNTS NEAR THAT
DEPICTED BY THE SREF.

LOOK FOR LIGHT PRECIP TO REACH THE IMMEDIATE COAST LATE ON SUNDAY
FROM NEAR CAPE MENDOCINO NORTHWARD TO THE CA/ORE BORDER BEFORE
SPREADING OVER THE COASTAL MOUNTAINS FROM THE SONOMA COUNTY COAST TO
THE CA/ORE BORDER...AS WELL AS THE IMMEDIATE CREST OF THE SOUTHERN
OREGON CASCADES OVERNIGHT INTO MONDAY MORNING. THE MOISTURE PLUME
ENTRAINED INTO THE SYSTEM AHEAD OF THE COLD FRONT WILL NARROW AND
ERODE AS IT NEARS THE COAST. PW VALUES NEAR 1.00-INCH WILL REACH THE
NORTH COAST WITH LESSER AMOUNTS REACHING INLAND TOWARD THE SIERRA.

INTO MONDAY...THE S/WV TROF WILL REACH THE NORTH COAST AND MOVE
INLAND DURING THE LATTER HALF OF THE DAY. PRECIP WILL SHIFT ITS
FOCUS FROM THE NORTH COAST INLAND AND SOUTH...AFFECTING THE NORTHERN
SIERRA...SF BAY AREA AND SACRAMENTO AREA AS WELL. THE SOUTHERN
EXTENT OF THE PRECIP WILL REACH DOWN TO THE SANTA CRUZ MOUNTAINS AND
THEN INLAND TOWARD YOSEMITE NP. WITH ENOUGH DYNAMICS FROM THE S/WV
TROF TRACKING ACROSS NORTHERN NEVADA...EXPECT PRECIP TO AFFECT THE
NORTHERN HALF OF THE STATE LATER MONDAY INTO EARLY TUESDAY. BY
SUNRISE ON TUESDAY...THE S/WV TROF WILL HAVE EXITED THE REGION
TOWARD THE NE WITH A WEAK LINGERING SECONDARY S/WV TROF PASSING
THROUGH DURING THE FIRST HALF OF THE DAY FOR A FEW REMAINING
SHOWERS.

FOR THE MIDDLE OF NEXT WEEK INTO THE NEXT WEEKEND...THE EC IS THE
MODEL OF CHOICE AS THE GFS HAS BEEN TRENDED TOWARD THIS SOLUTION.
YESTERDAY...THE EC SHOWED A FAIRLY STRONG UPR RIDGE DEVELOPING NEAR
THE 4-CORNERS REGION AND PUSHING THE NEXT MOISTURE PLUME TO THE
PACNW...WHILE THE GFS WANTED TO KEEP MORE SWLY FLOW ACROSS CA AND
THE BAROCLINIC ZONE FOCUSED NEAR THE CA/ORE BORDER. THE 18/00Z EC
HAS STUCK TO ITS SOLUTION...WHILE THE 18/00Z TO 18/06Z CHANGE OF THE
GFS WAS TO PUSH THE PRECIP FARTHER NORTH. AS A RESULT...HAVE DECIDED
TO FOLLOW THE MORE CONSISTENT EC...AND HOPING THE TREND OF THE GFS
TOWARD THE EC SOLUTION CONTINUES. THIS WOULD SPELL A DRIER AND
WARMER PERIOD.


.HYDROLOGICAL CONDITIONS...

NO APPRECIABLE RISES WERE OBSERVED FROM PRECIPITATION THAT FELL
DURING THE LAST 24 HOURS.  ONLY SMALL RISES ARE EXPECTED ON NORTH
COAST RIVERS AND STREAMS FROM PRECIPITATION FORECAST TO ARRIVE LATE
SUNDAY INTO MONDAY.

ALL RIVER FORECAST POINTS ARE EXPECTED TO REMAIN BELOW MONITOR
LEVELS DURING THE NEXT SEVERAL DAYS.


MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

DRK/AT

$$





000
AGUS76 KRSA 181549
HMDRSA

HYDROMETEOROLOGICAL DISCUSSION NATIONAL WEATHER SERVICE / CALIFORNIA
NEVADA RFC / SACRAMENTO CA 845 AM PDT SAT OCT 18 2014

...NEXT SYSTEM MOVES IN LATE SUNDAY INTO MONDAY...

.24 HOUR PRECIPITATION TOTALS (ENDING OCT 18 AT 500 AM PDT)...

A WEAKENING SYSTEM MOVED ACROSS THE YESTERDAY WITH PRECIP BEING
CONFINED TO THE UPPER KLAMATH RIVER BASIN AND COASTAL SECTIONS FROM
THE SMITH RIVER BASIN SOUTH TO THE RUSSIAN RIVER BASIN.

AMOUNTS IN THE UPPER KLAMATH RIVER BASIN WERE SCATTERED AND IN
GENERAL FROM A FEW HUNDREDTHS OF AN INCH TO 0.10-INCH. ALONG COASTAL
SECTIONS THE GREATEST AMOUNTS FELL BETWEEN CAPE MENDOCINO AND THE
SMITH RIVER BASIN. TOTALS IN THERE AREA WERE IN THE RANGE OF 0.25-
TO 0.50-INCH WITH A FEW AMOUNTS OVER THE KING RANGE NEAR CAPE
MENDOCINO REACHED AND SLIGHTLY SURPASSED THE 1.00-INCH MARK. SOUTH
ACROSS MENDOCINO AND SONOMA COUNTIES AMOUNTS TRAILED OFF FROM NORTH
TO SOUTH WITH TOTALS IN THE FAR NORTH NEAR 0.50-INCH AND 0.10-INCH
IN THE SOUTH.

OTHERWISE...THE REST OF THE REGION REMAINED DRY ON FRIDAY.


.METEOROLOGICAL CONDITIONS (SAT AM - FRI AM)...

AS EXPECTED...THE INCOMING SYSTEM YESTERDAY HAS SPLIT WITH THE MORE
PROGRESSIVE NORTHERN PIECE MOVING OFF TOWARD THE ENE AND NEAR THE
NORTHERN ROCKIES...WHILE THE SLOWER SOUTHERN PIECE IS FORMING A WEAK
UPR LOW OVER SOUTHERN CA. THERE ARE A FEW ECHOES STREAMING FROM
SOUTH TO NORTH ACROSS CLARK AND LINCOLN COUNTIES AHEAD OF THE UPR
LOW...BUT LOOKING AT THE 18/12Z KVEF RAOB...MUCH OF THE MOISTURE
RESIDES IN THE MID-LEVELS WITH A FAIRLY DRY SUB-CLOUD LAYER. NOT
EXPECTING ANY MEASURABLE PRECIP IN THIS AREA. ALSO...THERE ARE A FEW
LINGERING SHOWERS ALONG THE FAR NORTH COAST THIS MORNING. THIS
PRECIP IS EXPECTED TO WRAP UP DURING THE MORNING HOURS WITH A
POSITIVELY TILTED UPR RIDGE NUDGING OVER NORTHERN CA.

ATTENTION NEXT TURNS TO THE PARENT UPR LOW SPINNING OVER THE GULF OF
ALASKA NEAR 50N/147W AND THE ASSOCIATED UPR TROF CROSSING 150W. THIS
WILL BE THE NEXT OPPORTUNITY FOR PRECIP ACROSS THE NORTHERN PORTION
OF THE REGION. THERE ARE A FEW DISCREPANCIES AMONGST THE MODELS IN
TERMS OF THE STRENGTH OF THE S/WV TROF MOVING ACROSS THE REGION. THE
18/00Z GEM IS THE SHALLOWEST...THE 18/00Z AND 18/06Z GFS THE
DEEPEST...AND THE 18/00Z EC ALONG WITH THE 18/06Z NAM IN BETWEEN THE
TWO. AS A RESULT...THE GFS IS THE WETTEST WITH THE GEM THE DRIEST.
THE OTHER TWO ARE A GOOD COMPROMISE. ALSO...THE 18/09Z SREF LOOKS TO
BE A DECENT COMPROMISE AS WELL. A MIDDLE OF THE ROAD APPROACH WAS
TAKEN WITH THIS SYSTEM FOLLOWING WITH PRECIP AMOUNTS NEAR THAT
DEPICTED BY THE SREF.

LOOK FOR LIGHT PRECIP TO REACH THE IMMEDIATE COAST LATE ON SUNDAY
FROM NEAR CAPE MENDOCINO NORTHWARD TO THE CA/ORE BORDER BEFORE
SPREADING OVER THE COASTAL MOUNTAINS FROM THE SONOMA COUNTY COAST TO
THE CA/ORE BORDER...AS WELL AS THE IMMEDIATE CREST OF THE SOUTHERN
OREGON CASCADES OVERNIGHT INTO MONDAY MORNING. THE MOISTURE PLUME
ENTRAINED INTO THE SYSTEM AHEAD OF THE COLD FRONT WILL NARROW AND
ERODE AS IT NEARS THE COAST. PW VALUES NEAR 1.00-INCH WILL REACH THE
NORTH COAST WITH LESSER AMOUNTS REACHING INLAND TOWARD THE SIERRA.

INTO MONDAY...THE S/WV TROF WILL REACH THE NORTH COAST AND MOVE
INLAND DURING THE LATTER HALF OF THE DAY. PRECIP WILL SHIFT ITS
FOCUS FROM THE NORTH COAST INLAND AND SOUTH...AFFECTING THE NORTHERN
SIERRA...SF BAY AREA AND SACRAMENTO AREA AS WELL. THE SOUTHERN
EXTENT OF THE PRECIP WILL REACH DOWN TO THE SANTA CRUZ MOUNTAINS AND
THEN INLAND TOWARD YOSEMITE NP. WITH ENOUGH DYNAMICS FROM THE S/WV
TROF TRACKING ACROSS NORTHERN NEVADA...EXPECT PRECIP TO AFFECT THE
NORTHERN HALF OF THE STATE LATER MONDAY INTO EARLY TUESDAY. BY
SUNRISE ON TUESDAY...THE S/WV TROF WILL HAVE EXITED THE REGION
TOWARD THE NE WITH A WEAK LINGERING SECONDARY S/WV TROF PASSING
THROUGH DURING THE FIRST HALF OF THE DAY FOR A FEW REMAINING
SHOWERS.

FOR THE MIDDLE OF NEXT WEEK INTO THE NEXT WEEKEND...THE EC IS THE
MODEL OF CHOICE AS THE GFS HAS BEEN TRENDED TOWARD THIS SOLUTION.
YESTERDAY...THE EC SHOWED A FAIRLY STRONG UPR RIDGE DEVELOPING NEAR
THE 4-CORNERS REGION AND PUSHING THE NEXT MOISTURE PLUME TO THE
PACNW...WHILE THE GFS WANTED TO KEEP MORE SWLY FLOW ACROSS CA AND
THE BAROCLINIC ZONE FOCUSED NEAR THE CA/ORE BORDER. THE 18/00Z EC
HAS STUCK TO ITS SOLUTION...WHILE THE 18/00Z TO 18/06Z CHANGE OF THE
GFS WAS TO PUSH THE PRECIP FARTHER NORTH. AS A RESULT...HAVE DECIDED
TO FOLLOW THE MORE CONSISTENT EC...AND HOPING THE TREND OF THE GFS
TOWARD THE EC SOLUTION CONTINUES. THIS WOULD SPELL A DRIER AND
WARMER PERIOD.


.HYDROLOGICAL CONDITIONS...

NO APPRECIABLE RISES WERE OBSERVED FROM PRECIPITATION THAT FELL
DURING THE LAST 24 HOURS.  ONLY SMALL RISES ARE EXPECTED ON NORTH
COAST RIVERS AND STREAMS FROM PRECIPITATION FORECAST TO ARRIVE LATE
SUNDAY INTO MONDAY.

ALL RIVER FORECAST POINTS ARE EXPECTED TO REMAIN BELOW MONITOR
LEVELS DURING THE NEXT SEVERAL DAYS.


MORE INFORMATION ON THE CNRFC WEBSITE AT HTTP://WWW.CNRFC.NOAA.GOV

DRK/AT

$$





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