000
FXUS66 KPDT 200519
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1022 PM PDT SUN MAY 19 2013
.SHORT TERM...WEAK INSTABILITY TODAY RESULTED IN CUMULUS FORMATION
ACROSS MUCH OF THE FORECAST AREA ALONG WITH ISOLATED SHOWERS
ESPECIALLY OVER CENTRAL AND NORTHEAST OREGON. SATELLITE TRENDS SHOW
CLOUDS TO BE DECREASING AS SUNSET APPROACHES. EXPECT THIS TO
CONTINUE WITH CLEAR TO PARTLY CLOUDY SKIES OVERNIGHT. BREEZY
NORTHWEST WINDS ALONG THE EAST SLOPES OF THE CASCADES WILL DIMINISH
OVERNIGHT. UPPER LEVEL RIDGE WILL BRING MOSTLY SUNNY SKIES MONDAY
WITH HIGHS IN THE 70S. WINDS WILL BE LIGHTER. A STRONG UPPER LEVEL
LOW APPROACHING THE PACIFIC NORTHWEST WILL PUSH A COLD FRONT THROUGH
THE REGION TUESDAY. THIS WILL PRODUCE SHOWERS ALONG WITH COOLER
TEMPERATURES AND BREEZY WEST WINDS. THE LOW WILL LINGER OVER
WASHINGTON AND OREGON WEDNESDAY THROUGH FRIDAY WITH SHOWERS AND COOL
TEMPERATURES. 94
.AVIATION...06Z TAFS. CLEAR SKIES TONIGHT WITH SOME THIN CIRRUS ON
MONDAY. SURFACE WINDS 5-15KT. 94
&&
.PREV DISCUSSION... /ISSUED 249 PM PDT SUN MAY 19 2013/
SHORT TERM...TONIGHT THROUGH WEDNESDAY...AN UPPER TROUGH OVER THE
NORTHERN ROCKIES WILL CONTINUE TO SHIFT EAST TONIGHT ALLOWING HIGH
PRESSURE TO BUILD OVER THE PACIFIC NORTHWEST. LIGHT, ISOLATED
SHOWERS ARE OCCURRING OVER THE AREA EARLY THIS AFTERNOON, MAINLY
OVER THE HIGHER TERRAIN. THESE SHOWERS ARE DUE TO DAYTIME HEATING
AND UPSLOPE FLOW AFFECTS, AND ARE COVERING A BIT MORE OF THE AREA
THAN EARLIER EXPECTED. THESE SHOWERS SHOULD GRADUALLY DISSIPATE THIS
EVENING AS DRIER AIR MOVES IN AND THE AFTERNOON HEATING ENDS.
LOCALLY BREEZY WINDS WILL ALSO DECREASE THROUGH THE NIGHT TONIGHT.
THE HIGH PRESSURE AREA WILL BE OVER THE PACNW LATE TONIGHT THROUGH
MONDAY EVENING. AS SUCH EXPECT FAIR AND DRY CONDITIONS DURING THIS
PERIOD. MONDAY`S AFTERNOON HIGH TEMPS WILL BE THE WARMEST OF THE
WEEK. A DEEP UPPER LEVEL LOW WILL SLIDE SOUTH OUT OF NORTHERN
BRITISH COLUMBIA TO THE PACNW COAST LATE MONDAY NIGHT THROUGH
TUESDAY. THIS LOW WILL THEN DRIFT ONSHORE INTO THE PACNW TUESDAY
NIGHT AND WEDNESDAY. INITIALLY THIS SYSTEM WILL PUSH A COLD FRONT
THROUGH THE REGION LATE TUESDAY MORNING THROUGH TUESDAY AFTERNOON.
THIS FRONT WILL BRING INCREASING WINDS, CHANCES FOR SHOWERS AND
FALLING TEMPS. THIS FRONT MAY ALSO CAUSE A FEW THUNDERSTORMS TO
DEVELOP AHEAD OF IT. AT THIS TIME THE MOST LIKELY AREA TO SEE A
THUNDERSTORM WILL THE BLUE MOUNTAINS SOUTH TO GRANT COUNTY AND EAST
TO WALLOWA COUNTY. AS THE UPPER LOW SHIFTS ONSHORE WILL SEE A
CONTINUING CHANCE OF SHOWERS, SOME OF WHICH WILL CAUSE SNOW AS SNOW
LEVELS WILL FALL TUESDAY NIGHT. EXPECT SNOW LEVELS TO RUN BETWEEN
3000 AND 4000 FEET EARLY WEDNESDAY MORNING, THEN TO RISE TO BETWEEN
4000 AND 4500 FEET WEDNESDAY AFTERNOON. AT THIS TIME SNOW AMOUNTS
LOOK TO RUN 1 TO 3 INCHES ABOVE 4000 FEET. THERE IS SOME LINGERING
UNCERTAINTY CONCERNING WHERE HEAVIER PRECIP BANDS MAY SET UP, SO
HIGH SNOW AMOUNTS MAY BE POSSIBLE. 90
LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...COOLER THAN NORMAL
WITH UNSETTLED SHOWERY CONDITIONS WILL PREVAIL AS UPPER LEVEL LOW
MEANDERS OVER THE AREA INTO SATURDAY AND THEN LIFTS TO THE NORTH ON
SUNDAY. SNOW LEVELS START OUT 3500-4500 ON THURSDAY. BOTH EC AND GFS
ARE IN QUITE GOOD AGREEMENT ON THIS PATTERN. HAVE INTRODUCED
ISOLATED THUNDERSTORMS FOR PORTIONS OF WALLOWA...UNION AND GRANT
COUNTIES FOR FRIDAY AND SUNDAY AFTERNOONS AS GFS SHOWS SOME
INSTABILITY AT THIS TIME. WITH UPPER LOW OVER THE AREA AND WEAK
SURFACE GRADIENTS...WINDS SHOULD BE ON THE LIGHT SIDE UNTIL LOW
MOVES NORTH ON SUNDAY AND THEN SURFACE GRADIENTS INCREASE
SLIGHTLY...ESPECIALLY CLOSER TO THE CASCADES.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 44 76 50 69 / 10 0 0 30
ALW 50 78 53 72 / 10 0 0 30
PSC 44 81 49 74 / 0 0 0 20
YKM 40 78 45 68 / 0 0 0 30
HRI 42 80 47 72 / 0 0 0 20
ELN 44 78 47 66 / 0 0 0 40
RDM 31 75 43 64 / 0 0 0 20
LGD 42 73 45 70 / 20 0 0 30
GCD 40 75 42 70 / 20 0 0 30
DLS 46 81 51 67 / 0 0 0 50
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
94/
000
FXUS66 KPDT 200247
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
745 PM PDT SUN MAY 19 2013
.SHORT TERM...WEAK INSTABILITY TODAY RESULTED IN CUMULUS FORMATION
ACROSS MUCH OF THE FORECAST AREA ALONG WITH ISOLATED SHOWERS
ESPECIALLY OVER CENTRAL AND NORTHEAST OREGON. SATELLITE TRENDS SHOW
CLOUDS TO BE DECREASING AS SUNSET APPROACHES. EXPECT THIS TO
CONTINUE WITH CLEAR TO PARTLY CLOUDY SKIES OVERNIGHT. BREEZY
NORTHWEST WINDS ALONG THE EAST SLOPES OF THE CASCADES WILL DIMINISH
OVERNIGHT. UPPER LEVEL RIDGE WILL BRING MOSTLY SUNNY SKIES MONDAY
WITH HIGHS IN THE 70S. WINDS WILL BE LIGHTER. A STRONG UPPER LEVEL
LOW APPROACHING THE PACIFIC NORTHWEST WILL PUSH A COLD FRONT THROUGH
THE REGION TUESDAY. THIS WILL PRODUCE SHOWERS ALONG WITH COOLER
TEMPERATURES AND BREEZY WEST WINDS. THE LOW WILL LINGER OVER
WASHINGTON AND OREGON WEDNESDAY THROUGH FRIDAY WITH SHOWERS AND COOL
TEMPERATURES. 94
&&
.PREV DISCUSSION... /ISSUED 249 PM PDT SUN MAY 19 2013/
SHORT TERM...TONIGHT THROUGH WEDNESDAY...AN UPPER TROUGH OVER THE
NORTHERN ROCKIES WILL CONTINUE TO SHIFT EAST TONIGHT ALLOWING HIGH
PRESSURE TO BUILD OVER THE PACIFIC NORTHWEST. LIGHT, ISOLATED
SHOWERS ARE OCCURRING OVER THE AREA EARLY THIS AFTERNOON, MAINLY
OVER THE HIGHER TERRAIN. THESE SHOWERS ARE DUE TO DAYTIME HEATING
AND UPSLOPE FLOW AFFECTS, AND ARE COVERING A BIT MORE OF THE AREA
THAN EARLIER EXPECTED. THESE SHOWERS SHOULD GRADUALLY DISSIPATE THIS
EVENING AS DRIER AIR MOVES IN AND THE AFTERNOON HEATING ENDS.
LOCALLY BREEZY WINDS WILL ALSO DECREASE THROUGH THE NIGHT TONIGHT.
THE HIGH PRESSURE AREA WILL BE OVER THE PACNW LATE TONIGHT THROUGH
MONDAY EVENING. AS SUCH EXPECT FAIR AND DRY CONDITIONS DURING THIS
PERIOD. MONDAY`S AFTERNOON HIGH TEMPS WILL BE THE WARMEST OF THE
WEEK. A DEEP UPPER LEVEL LOW WILL SLIDE SOUTH OUT OF NORTHERN
BRITISH COLUMBIA TO THE PACNW COAST LATE MONDAY NIGHT THROUGH
TUESDAY. THIS LOW WILL THEN DRIFT ONSHORE INTO THE PACNW TUESDAY
NIGHT AND WEDNESDAY. INITIALLY THIS SYSTEM WILL PUSH A COLD FRONT
THROUGH THE REGION LATE TUESDAY MORNING THROUGH TUESDAY AFTERNOON.
THIS FRONT WILL BRING INCREASING WINDS, CHANCES FOR SHOWERS AND
FALLING TEMPS. THIS FRONT MAY ALSO CAUSE A FEW THUNDERSTORMS TO
DEVELOP AHEAD OF IT. AT THIS TIME THE MOST LIKELY AREA TO SEE A
THUNDERSTORM WILL THE BLUE MOUNTAINS SOUTH TO GRANT COUNTY AND EAST
TO WALLOWA COUNTY. AS THE UPPER LOW SHIFTS ONSHORE WILL SEE A
CONTINUING CHANCE OF SHOWERS, SOME OF WHICH WILL CAUSE SNOW AS SNOW
LEVELS WILL FALL TUESDAY NIGHT. EXPECT SNOW LEVELS TO RUN BETWEEN
3000 AND 4000 FEET EARLY WEDNESDAY MORNING, THEN TO RISE TO BETWEEN
4000 AND 4500 FEET WEDNESDAY AFTERNOON. AT THIS TIME SNOW AMOUNTS
LOOK TO RUN 1 TO 3 INCHES ABOVE 4000 FEET. THERE IS SOME LINGERING
UNCERTAINTY CONCERNING WHERE HEAVIER PRECIP BANDS MAY SET UP, SO
HIGH SNOW AMOUNTS MAY BE POSSIBLE. 90
LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...COOLER THAN NORMAL
WITH UNSETTLED SHOWERY CONDITIONS WILL PREVAIL AS UPPER LEVEL LOW
MEANDERS OVER THE AREA INTO SATURDAY AND THEN LIFTS TO THE NORTH ON
SUNDAY. SNOW LEVELS START OUT 3500-4500 ON THURSDAY. BOTH EC AND GFS
ARE IN QUITE GOOD AGREEMENT ON THIS PATTERN. HAVE INTRODUCED
ISOLATED THUNDERSTORMS FOR PORTIONS OF WALLOWA...UNION AND GRANT
COUNTIES FOR FRIDAY AND SUNDAY AFTERNOONS AS GFS SHOWS SOME
INSTABILITY AT THIS TIME. WITH UPPER LOW OVER THE AREA AND WEAK
SURFACE GRADIENTS...WINDS SHOULD BE ON THE LIGHT SIDE UNTIL LOW
MOVES NORTH ON SUNDAY AND THEN SURFACE GRADIENTS INCREASE
SLIGHTLY...ESPECIALLY CLOSER TO THE CASCADES.
AVIATION...00Z TAFS...VFR CONDITIONS WITH LIGHT WINDS. FEW-SCT
CUMULUS WILL DISSIPATE BY SUNSET. A DRIER AIRMASS AND WEAK RIDGE
SHOULD PROMOTE SKC THROUGH 23Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 44 76 50 69 / 10 0 0 30
ALW 50 78 53 72 / 10 0 0 30
PSC 44 81 49 74 / 0 0 0 20
YKM 40 78 45 68 / 0 0 0 30
HRI 42 80 47 72 / 0 0 0 20
ELN 44 78 47 66 / 0 0 0 40
RDM 31 75 43 64 / 0 0 0 20
LGD 42 73 45 70 / 20 0 0 30
GCD 40 75 42 70 / 20 0 0 30
DLS 46 81 51 67 / 0 0 0 50
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
94/
000
FXUS66 KPDT 192149
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
249 PM PDT SUN MAY 19 2013
.SHORT TERM...TONIGHT THROUGH WEDNESDAY...AN UPPER TROUGH OVER THE
NORTHERN ROCKIES WILL CONTINUE TO SHIFT EAST TONIGHT ALLOWING HIGH
PRESSURE TO BUILD OVER THE PACIFIC NORTHWEST. LIGHT, ISOLATED
SHOWERS ARE OCCURRING OVER THE AREA EARLY THIS AFTERNOON, MAINLY
OVER THE HIGHER TERRAIN. THESE SHOWERS ARE DUE TO DAYTIME HEATING
AND UPSLOPE FLOW AFFECTS, AND ARE COVERING A BIT MORE OF THE AREA
THAN EARLIER EXPECTED. THESE SHOWERS SHOULD GRADUALLY DISSIPATE THIS
EVENING AS DRIER AIR MOVES IN AND THE AFTERNOON HEATING ENDS.
LOCALLY BREEZY WINDS WILL ALSO DECREASE THROUGH THE NIGHT TONIGHT.
THE HIGH PRESSURE AREA WILL BE OVER THE PACNW LATE TONIGHT THROUGH
MONDAY EVENING. AS SUCH EXPECT FAIR AND DRY CONDITIONS DURING THIS
PERIOD. MONDAY`S AFTERNOON HIGH TEMPS WILL BE THE WARMEST OF THE
WEEK. A DEEP UPPER LEVEL LOW WILL SLIDE SOUTH OUT OF NORTHERN
BRITISH COLUMBIA TO THE PACNW COAST LATE MONDAY NIGHT THROUGH
TUESDAY. THIS LOW WILL THEN DRIFT ONSHORE INTO THE PACNW TUESDAY
NIGHT AND WEDNESDAY. INITIALLY THIS SYSTEM WILL PUSH A COLD FRONT
THROUGH THE REGION LATE TUESDAY MORNING THROUGH TUESDAY AFTERNOON.
THIS FRONT WILL BRING INCREASING WINDS, CHANCES FOR SHOWERS AND
FALLING TEMPS. THIS FRONT MAY ALSO CAUSE A FEW THUNDERSTORMS TO
DEVELOP AHEAD OF IT. AT THIS TIME THE MOST LIKELY AREA TO SEE A
THUNDERSTORM WILL THE BLUE MOUNTAINS SOUTH TO GRANT COUNTY AND EAST
TO WALLOWA COUNTY. AS THE UPPER LOW SHIFTS ONSHORE WILL SEE A
CONTINUING CHANCE OF SHOWERS, SOME OF WHICH WILL CAUSE SNOW AS SNOW
LEVELS WILL FALL TUESDAY NIGHT. EXPECT SNOW LEVELS TO RUN BETWEEN
3000 AND 4000 FEET EARLY WEDNESDAY MORNING, THEN TO RISE TO BETWEEN
4000 AND 4500 FEET WEDNESDAY AFTERNOON. AT THIS TIME SNOW AMOUNTS
LOOK TO RUN 1 TO 3 INCHES ABOVE 4000 FEET. THERE IS SOME LINGERING
UNCERTAINTY CONCERNING WHERE HEAVIER PRECIP BANDS MAY SET UP, SO
HIGH SNOW AMOUNTS MAY BE POSSIBLE. 90
.LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...COOLER THAN NORMAL
WITH UNSETTLED SHOWERY CONDITIONS WILL PREVAIL AS UPPER LEVEL LOW
MEANDERS OVER THE AREA INTO SATURDAY AND THEN LIFTS TO THE NORTH ON
SUNDAY. SNOW LEVELS START OUT 3500-4500 ON THURSDAY. BOTH EC AND GFS
ARE IN QUITE GOOD AGREEMENT ON THIS PATTERN. HAVE INTRODUCED
ISOLATED THUNDERSTORMS FOR PORTIONS OF WALLOWA...UNION AND GRANT
COUNTIES FOR FRIDAY AND SUNDAY AFTERNOONS AS GFS SHOWS SOME
INSTABILITY AT THIS TIME. WITH UPPER LOW OVER THE AREA AND WEAK
SURFACE GRADIENTS...WINDS SHOULD BE ON THE LIGHT SIDE UNTIL LOW
MOVES NORTH ON SUNDAY AND THEN SURFACE GRADIENTS INCREASE
SLIGHTLY...ESPECIALLY CLOSER TO THE CASCADES.
&&
.AVIATION...00Z TAFS...VFR CONDITIONS WITH LIGHT WINDS. FEW-SCT
CUMULUS WILL DISSIPATE BY SUNSET. A DRIER AIRMASS AND WEAK RIDGE
SHOULD PROMOTE SKC THROUGH 23Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 44 76 50 70 / 10 0 0 30
ALW 50 78 53 73 / 10 0 0 30
PSC 44 81 49 75 / 0 0 0 20
YKM 40 78 45 70 / 0 0 0 30
HRI 42 80 47 73 / 0 0 0 20
ELN 44 78 47 67 / 0 0 0 40
RDM 31 75 43 65 / 0 0 0 20
LGD 42 73 45 71 / 20 0 0 30
GCD 40 75 42 71 / 20 0 0 30
DLS 46 81 51 68 / 0 0 0 50
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
MONDAY : GREEN
TUESDAY : GREEN
WEDNESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/79/79
000
FXUS66 KPDT 191743 AAA
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1045 AM PDT SUN MAY 19 2013
UPDATED AVIATION
.SHORT TERM...UPDATE...HIGH PRESSURE WILL GRADUALLY BUILD OVER THE
REGION TODAY AND TONIGHT AS AN UPPER TROUGH SHIFTS EAST TO THE UPPER
PLAINS. WILL SEE A GRADUAL DRYING AND STABILIZATION AS THE HIGH
PUSHES IN FROM THE WEST. WILL ALSO SEE LOCALLY BREEZY WINDS DUE TO
THIS HIGH PRESSURE. NORTHWEST FLOW ALOFT WILL RESULT IN UPSLOPE
AFFECTS THAT WILL CAUSE ISOLATED SHOWERS ALONG SOME OF THE MOUNTAINS
TODAY. A BAND OF SHOWERS THIS MORNING OVER FRANKLIN AND BENTON
COUNTIES IS DRIFTING INTO THE BLUE MOUNTAIN FOOTHILLS OF UMATILLA
AND WALLA WALLA COUNTIES. EXPECT THESE SHOWERS TO PERSIST IN THE
FOOTHILLS THROUGH MID MORNING. SHOULD SEE FURTHER DRYING WITH AN END
TO THE SHOWER THREAT AND CLEARING OF THE SKIES TONIGHT. ADJUSTMENTS
TO SKY COVER, TEMPS, WINDS AND WEATHER BASED ON CURRENT TRENDS WERE
THE UPDATES THIS MORNING. 90
.LONG TERM...PREVIOUS DISCUSSION...A LARGE MID/UPPER LEVEL TROUGH
WILL BE OVER THE NE PACIFIC WEST OF VANCOUVER ISLAND AROUND DAYBREAK
TUESDAY. THE TROUGH EVOLVES INTO A LARGE MID/UPPER LEVEL LOW TUESDAY
MORNING WITH THE LOW MOVING SOUTHEAST. THE CENTER OF THE LOW
APPROACHES THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE TUESDAY
AFTERNOON. A COLD FRONT ON THE EASTERN FLANK OF THE LOW WILL MOVE
INTO THE WESTERN SECTIONS OF THE FORECAST AREA LATE TUESDAY
AFTERNOON. THE COLD FRONT WILL THEN MOVE EAST AND SPREAD INCREASING
MOISTURE AND SHOWERS ACROSS SOUTHEAST WASHINGTON AND NORTHEAST
OREGON TUESDAY EVENING. MARGINAL INSTABILITY MAY TRIGGER SOME
ISOLATED THUNDERSTORMS TUESDAY AFTERNOON AND TUESDAY EVENING IN THE
WALLOWA MOUNTAINS AND WALLOWA COUNTY. THE COLD UPPER LOW WILL USHER
IN A COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE
UPPER LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH
FRIDAY. THE UPPER LOW MOVES NORTHEAST INTO SOUTHWEST CANADA SATURDAY
IN RESPONSE TO A TROUGH MOVING EAST INTO THE GULF OF ALASKA. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY. HIGH TEMPS WILL WARM TO NEAR NORMAL ON SATURDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS OF NE OREGON AND SE
WASHINGTON. HOWEVER, WILL AWAIT SPC GUIDANCE BEFORE INTRODUCING A
SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY AFTERNOON/EVENING AT
THIS TIME SINCE THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL
COVERAGE OF THUNDERSTORM POTENTIAL. CANNOT RULE OUT SOME ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON/EVENING GIVEN 500MB TEMPERATURES
AROUND -28 DEGREES CELSIUS, WHICH IS COLD ENOUGH TO YIELD STEEP
TEMPERATURE LAPSE RATES AND THUS MARGINAL INSTABILITY FAVORABLE FOR
THUNDERSTORM DEVELOPMENT. POLAN
&&
.AVIATION...18Z TAFS...VFR CONDITIONS WILL OCCUR FOR THE NEXT 24
HOURS AT ALL TAF SITES. BKN CLOUD COVER WILL GRADUALLY LIFT AND GIVE
WAY TO SCT AFT 20Z AND THEN SKC AFT 02Z. A MODERATE WEST TO EAST
PRESSURE GRADIENT WILL GIVE G25 KT WINDS AT KDLS TIL 03Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 70 44 76 49 / 10 0 0 0
ALW 71 49 79 53 / 20 0 0 0
PSC 76 43 81 48 / 20 0 0 0
YKM 74 44 78 46 / 10 0 0 0
HRI 74 43 80 47 / 10 0 0 0
ELN 71 45 79 46 / 10 0 0 0
RDM 66 32 75 44 / 10 0 0 0
LGD 64 39 73 45 / 20 0 0 0
GCD 66 40 74 42 / 10 0 0 0
DLS 72 46 80 51 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/99/79
000
FXUS66 KPDT 191613
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
912 AM PDT SUN MAY 19 2013
.SHORT TERM...UPDATE...HIGH PRESSURE WILL GRADUALLY BUILD OVER THE
REGION TODAY AND TONIGHT AS AN UPPER TROUGH SHIFTS EAST TO THE UPPER
PLAINS. WILL SEE A GRADUAL DRYING AND STABILIZATION AS THE HIGH
PUSHES IN FROM THE WEST. WILL ALSO SEE LOCALLY BREEZY WINDS DUE TO
THIS HIGH PRESSURE. NORTHWEST FLOW ALOFT WILL RESULT IN UPSLOPE
AFFECTS THAT WILL CAUSE ISOLATED SHOWERS ALONG SOME OF THE MOUNTAINS
TODAY. A BAND OF SHOWERS THIS MORNING OVER FRANKLIN AND BENTON
COUNTIES IS DRIFTING INTO THE BLUE MOUNTAIN FOOTHILLS OF UMATILLA
AND WALLA WALLA COUNTIES. EXPECT THESE SHOWERS TO PERSIST IN THE
FOOTHILLS THROUGH MID MORNING. SHOULD SEE FURTHER DRYING WITH AN END
TO THE SHOWER THREAT AND CLEARING OF THE SKIES TONIGHT. ADJUSTMENTS
TO SKY COVER, TEMPS, WINDS AND WEATHER BASED ON CURRENT TRENDS WERE
THE UPDATES THIS MORNING. 90
.LONG TERM...PREVIOUS DISCUSSION...A LARGE MID/UPPER LEVEL TROUGH
WILL BE OVER THE NE PACIFIC WEST OF VANCOUVER ISLAND AROUND DAYBREAK
TUESDAY. THE TROUGH EVOLVES INTO A LARGE MID/UPPER LEVEL LOW TUESDAY
MORNING WITH THE LOW MOVING SOUTHEAST. THE CENTER OF THE LOW
APPROACHES THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE TUESDAY
AFTERNOON. A COLD FRONT ON THE EASTERN FLANK OF THE LOW WILL MOVE
INTO THE WESTERN SECTIONS OF THE FORECAST AREA LATE TUESDAY
AFTERNOON. THE COLD FRONT WILL THEN MOVE EAST AND SPREAD INCREASING
MOISTURE AND SHOWERS ACROSS SOUTHEAST WASHINGTON AND NORTHEAST
OREGON TUESDAY EVENING. MARGINAL INSTABILITY MAY TRIGGER SOME
ISOLATED THUNDERSTORMS TUESDAY AFTERNOON AND TUESDAY EVENING IN THE
WALLOWA MOUNTAINS AND WALLOWA COUNTY. THE COLD UPPER LOW WILL USHER
IN A COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE
UPPER LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH
FRIDAY. THE UPPER LOW MOVES NORTHEAST INTO SOUTHWEST CANADA SATURDAY
IN RESPONSE TO A TROUGH MOVING EAST INTO THE GULF OF ALASKA. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY. HIGH TEMPS WILL WARM TO NEAR NORMAL ON SATURDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS OF NE OREGON AND SE
WASHINGTON. HOWEVER, WILL AWAIT SPC GUIDANCE BEFORE INTRODUCING A
SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY AFTERNOON/EVENING AT
THIS TIME SINCE THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL
COVERAGE OF THUNDERSTORM POTENTIAL. CANNOT RULE OUT SOME ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON/EVENING GIVEN 500MB TEMPERATURES
AROUND -28 DEGREES CELSIUS, WHICH IS COLD ENOUGH TO YIELD STEEP
TEMPERATURE LAPSE RATES AND THUS MARGINAL INSTABILITY FAVORABLE FOR
THUNDERSTORM DEVELOPMENT. POLAN
&&
.AVIATION...PREVIOUS DISCUSSION...12Z TAFS...VFR CONDITIONS WILL
OCCUR FOR THE NEXT 24 HOURS AT ALL TAF SITES. HOWEVER, MVFR
CONDITIONS ARE EXPECTED TODAY ALONG THE AIR TRAFFIC ROUTE OVER THE
BLUE MOUNTAINS FROM KPDT TO KBKE DUE TO LOW CIGS. OTHERWISE, CLOUD
COVER WILL BE SCT-BKN 5000-8000 FT AGL THIS MORNING AS A WEAK UPPER
TROUGH IS MOVING THROUGH. THE UPPER TROUGH EXITS INTO IDAHO BY
MIDDAY WITH SCT 5000-8000 FT AGL THIS AFTERNOON. WINDS 5-15 KTS
EXCEPT 10-20 KTS AT KDLS.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 70 44 76 49 / 10 0 0 0
ALW 71 49 79 53 / 20 0 0 0
PSC 76 43 81 48 / 20 0 0 0
YKM 74 44 78 46 / 10 0 0 0
HRI 74 43 80 47 / 10 0 0 0
ELN 71 45 79 46 / 10 0 0 0
RDM 66 32 75 44 / 10 0 0 0
LGD 64 39 73 45 / 20 0 0 0
GCD 66 40 74 42 / 10 0 0 0
DLS 72 46 80 51 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/99/79
000
FXUS66 KPDT 191102 AAB
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
402 AM PDT SUN MAY 19 2013
UPDATED AVIATION DISCUSSION
.SHORT TERM...TODAY THROUGH MONDAY NIGHT...AN UPPER LEVEL RIDGE WILL
BUILD ALONG THE COAST TODAY. THIS WILL BRING A DRIER NORTHWEST FLOW
TO EASTERN WASHINGTON AND OREGON. LINGERING MOISTURE WILL COMBINE
WITH UPSLOPE EFFECTS TO TRIGGER A FEW SHOWERS FROM GRANT COUNTY TO
THE NORTHERN BLUES AND WALLOWA COUNTY. THESE SHOWERS WILL INCREASE
WITH AFTERNOON HEATING. THE RIDGE AXIS WILL SHIFT EAST TONIGHT AND
MOVE OVER EASTERN WASHINGTON AND OREGON MONDAY. SUBSIDENCE FROM THE
BUILDING RIDGE WILL WARM DAYTIME TEMPERATURES A FEW DEGREES TODAY
AND EVEN MORE MONDAY. CLEARING SKIES TONIGHT WILL ALLOW SOME
RADIATIONAL COOLING WITH COOLER OVERNIGHT TEMPERATURES. AN
APPROACHING PACIFIC SYSTEM WILL BRING INCREASING CLOUDS MONDAY NIGHT
AND MAY SPREAD SOME LIGHT PRECIPITATION TO THE WASHINGTON CASCADES.
COONFIELD
.LONG TERM...TUESDAY THROUGH SATURDAY...A LARGE MID/UPPER LEVEL
TROUGH WILL BE OVER THE NE PACIFIC WEST OF VANCOUVER ISLAND AROUND
DAYBREAK TUESDAY. THE TROUGH EVOLVES INTO A LARGE MID/UPPER LEVEL
LOW TUESDAY MORNING WITH THE LOW MOVING SOUTHEAST. THE CENTER OF THE
LOW APPROACHES THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE
TUESDAY AFTERNOON. A COLD FRONT ON THE EASTERN FLANK OF THE LOW WILL
MOVE INTO THE WESTERN SECTIONS OF THE FORECAST AREA LATE TUESDAY
AFTERNOON. THE COLD FRONT WILL THEN MOVE EAST AND SPREAD INCREASING
MOISTURE AND SHOWERS ACROSS SOUTHEAST WASHINGTON AND NORTHEAST
OREGON TUESDAY EVENING. MARGINAL INSTABILITY MAY TRIGGER SOME
ISOLATED THUNDERSTORMS TUESDAY AFTERNOON AND TUESDAY EVENING IN THE
WALLOWA MOUNTAINS AND WALLOWA COUNTY. THE COLD UPPER LOW WILL USHER
IN A COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE
UPPER LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH
FRIDAY. THE UPPER LOW MOVES NORTHEAST INTO SOUTHWEST CANADA SATURDAY
IN RESPONSE TO A TROUGH MOVING EAST INTO THE GULF OF ALASKA. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY. HIGH TEMPS WILL WARM TO NEAR NORMAL ON SATURDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS OF NE OREGON AND SE
WASHINGTON. HOWEVER, WILL AWAIT SPC GUIDANCE BEFORE INTRODUCING A
SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY AFTERNOON/EVENING AT
THIS TIME SINCE THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL
COVERAGE OF THUNDERSTORM POTENTIAL. CANNOT RULE OUT SOME ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON/EVENING GIVEN 500MB TEMPERATURES
AROUND -28 DEGREES CELSIUS, WHICH IS COLD ENOUGH TO YIELD STEEP
TEMPERATURE LAPSE RATES AND THUS MARGINAL INSTABILITY FAVORABLE FOR
THUNDERSTORM DEVELOPMENT. POLAN
&&
.AVIATION...12Z TAFS. VFR CONDITIONS WILL OCCUR FOR THE NEXT 24
HOURS AT ALL TAF SITES. HOWEVER, MVFR CONDITIONS ARE EXPECTED TODAY
ALONG THE AIR TRAFFIC ROUTE OVER THE BLUE MOUNTAINS FROM KPDT TO
KBKE DUE TO LOW CIGS. OTHERWISE, CLOUD COVER WILL BE SCT-BKN
5000-8000 FT AGL THIS MORNING AS A WEAK UPPER TROUGH IS MOVING
THROUGH. THE UPPER TROUGH EXITS INTO IDAHO BY MIDDAY WITH SCT
5000-8000 FT AGL THIS AFTERNOON. WINDS 5-15 KTS EXCEPT 10-20 KTS AT
KDLS. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 70 44 76 49 / 10 0 0 0
ALW 71 49 79 53 / 10 0 0 0
PSC 76 43 81 48 / 10 0 0 0
YKM 74 44 78 46 / 10 0 0 0
HRI 75 43 80 47 / 10 0 0 0
ELN 71 45 79 46 / 10 0 0 0
RDM 66 32 75 44 / 10 0 0 0
LGD 64 39 73 45 / 20 0 0 0
GCD 64 40 74 42 / 10 0 0 0
DLS 71 46 80 51 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 191058 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
358 AM PDT SUN MAY 19 2013
UPDATED AVIATION AND LONG TERM DISCUSSIONS
.SHORT TERM...TODAY THROUGH MONDAY NIGHT...AN UPPER LEVEL RIDGE WILL
BUILD ALONG THE COAST TODAY. THIS WILL BRING A DRIER NORTHWEST FLOW
TO EASTERN WASHINGTON AND OREGON. LINGERING MOISTURE WILL COMBINE
WITH UPSLOPE EFFECTS TO TRIGGER A FEW SHOWERS FROM GRANT COUNTY TO
THE NORTHERN BLUES AND WALLOWA COUNTY. THESE SHOWERS WILL INCREASE
WITH AFTERNOON HEATING. THE RIDGE AXIS WILL SHIFT EAST TONIGHT AND
MOVE OVER EASTERN WASHINGTON AND OREGON MONDAY. SUBSIDENCE FROM THE
BUILDING RIDGE WILL WARM DAYTIME TEMPERATURES A FEW DEGREES TODAY
AND EVEN MORE MONDAY. CLEARING SKIES TONIGHT WILL ALLOW SOME
RADIATIONAL COOLING WITH COOLER OVERNIGHT TEMPERATURES. AN
APPROACHING PACIFIC SYSTEM WILL BRING INCREASING CLOUDS MONDAY NIGHT
AND MAY SPREAD SOME LIGHT PRECIPITATION TO THE WASHINGTON CASCADES.
COONFIELD
.LONG TERM...TUESDAY THROUGH SATURDAY...A LARGE MID/UPPER LEVEL
TROUGH WILL BE OVER THE NE PACIFIC WEST OF VANCOUVER ISLAND AROUND
DAYBREAK TUESDAY. THE TROUGH EVOLVES INTO A LARGE MID/UPPER LEVEL
LOW TUESDAY MORNING WITH THE LOW MOVING SOUTHEAST. THE CENTER OF THE
LOW APPROACHES THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE
TUESDAY AFTERNOON. A COLD FRONT ON THE EASTERN FLANK OF THE LOW WILL
MOVE INTO THE WESTERN SECTIONS OF THE FORECAST AREA LATE TUESDAY
AFTERNOON. THE COLD FRONT WILL THEN MOVE EAST AND SPREAD INCREASING
MOISTURE AND SHOWERS ACROSS SOUTHEAST WASHINGTON AND NORTHEAST
OREGON TUESDAY EVENING. MARGINAL INSTABILITY MAY TRIGGER SOME
ISOLATED THUNDERSTORMS TUESDAY AFTERNOON AND TUESDAY EVENING IN THE
WALLOWA MOUNTAINS AND WALLOWA COUNTY. THE COLD UPPER LOW WILL USHER
IN A COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE
UPPER LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH
FRIDAY. THE UPPER LOW MOVES NORTHEAST INTO SOUTHWEST CANADA SATURDAY
IN RESPONSE TO A TROUGH MOVING EAST INTO THE GULF OF ALASKA. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY. HIGH TEMPS WILL WARM TO NEAR NORMAL ON SATURDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS OF NE OREGON AND SE
WASHINGTON. HOWEVER, WILL AWAIT SPC GUIDANCE BEFORE INTRODUCING A
SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY AFTERNOON/EVENING AT
THIS TIME SINCE THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL
COVERAGE OF THUNDERSTORM POTENTIAL. CANNOT RULE OUT SOME ISOLATED
THUNDERSTORMS WEDNESDAY AFTERNOON/EVENING GIVEN 500MB TEMPERATURES
AROUND -28 DEGREES CELSIUS, WHICH IS COLD ENOUGH TO YIELD STEEP
TEMPERATURE LAPSE RATES AND THUS MARGINAL INSTABILITY FAVORABLE FOR
THUNDERSTORM DEVELOPMENT. POLAN
&&
.PREVIOUS AVIATION DISCUSSION...12Z TAFS. VFR CONDITIONS WILL OCCUR
FOR THE NEXT 24 HOURS AT ALL TAF SITES. CLOUD COVER WILL BE SCT-BKN
5000-8000 FT AGL THIS MORNING AS A WEAK UPPER TROUGH IS MOVING
THROUGH. THE UPPER TROUGH EXITS INTO IDAHO BY MIDDAY WITH SCT
5000-8000 FT AGL THIS AFTERNOON. WINDS 5-15 KTS EXCEPT 10-20 KTS AT
KDLS. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 70 44 76 49 / 10 0 0 0
ALW 71 49 79 53 / 10 0 0 0
PSC 76 43 81 48 / 10 0 0 0
YKM 74 44 78 46 / 10 0 0 0
HRI 75 43 80 47 / 10 0 0 0
ELN 71 45 79 46 / 10 0 0 0
RDM 66 32 75 44 / 10 0 0 0
LGD 64 39 73 45 / 20 0 0 0
GCD 64 40 74 42 / 10 0 0 0
DLS 71 46 80 51 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 191007
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
307 AM PDT SUN MAY 19 2013
.SHORT TERM...TODAY THROUGH MONDAY NIGHT...AN UPPER LEVEL RIDGE WILL
BUILD ALONG THE COAST TODAY. THIS WILL BRING A DRIER NORTHWEST FLOW
TO EASTERN WASHINGTON AND OREGON. LINGERING MOISTURE WILL COMBINE
WITH UPSLOPE EFFECTS TO TRIGGER A FEW SHOWERS FROM GRANT COUNTY TO
THE NORTHERN BLUES AND WALLOWA COUNTY. THESE SHOWERS WILL INCREASE
WITH AFTERNOON HEATING. THE RIDGE AXIS WILL SHIFT EAST TONIGHT AND
MOVE OVER EASTERN WASHINGTON AND OREGON MONDAY. SUBSIDENCE FROM THE
BUILDING RIDGE WILL WARM DAYTIME TEMPERATURES A FEW DEGREES TODAY
AND EVEN MORE MONDAY. CLEARING SKIES TONIGHT WILL ALLOW SOME
RADIATIONAL COOLING WITH COOLER OVERNIGHT TEMPERATURES. AN
APPROACHING PACIFIC SYSTEM WILL BRING INCREASING CLOUDS MONDAY NIGHT
AND MAY SPREAD SOME LIGHT PRECIPITATION TO THE WASHINGTON CASCADES.
COONFIELD
.LONG TERM...TUESDAY THROUGH SATURDAY...TUESDAY THE LARGE UPPER
TROUGH EVOLVES INTO A LARGE MID/UPPER LEVEL LOW. THE LOW CONTINUES
MOVING SOUTHEAST WITH THE CENTER OF THE LOW APPROACHING THE COAST
JUST WEST OF THE COLUMBIA RIVER BY LATE TUESDAY AFTERNOON. THIS WILL
CAUSE A SOUTHWEST FLOW ALOFT TO BACK MORE TO THE SOUTH OVER THE
FORECAST AREA AND TRANSPORT MOISTURE AND INSTABILITY INTO THE
REGION. THE COLD UPPER LOW WILL USHER IN A COOLING TREND AND PERIODS
OF UNSETTLED SHOWERY WEATHER, AS THE UPPER LOW CENTER MOVES OVER THE
FORECAST AREA AND PERSISTS THROUGH FRIDAY. THE UPPER LOW MOVES
NORTHEAST INTO FAR SOUTHWEST CANADA IN RESPONSE TO A TROUGH MOVING
EAST INTO THE GULF OF ALASKA. DAYTIME HIGH TEMPERATURES WILL BE
SLIGHTLY COOLER THAN NORMAL FOR TUESDAY THROUGH FRIDAY. HIGH TEMPS
WILL WARM TO NEAR NORMAL ON SATURDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS. WILL REFRAIN FROM
INTRODUCING A SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY SINCE THIS
FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL COVERAGE OF
THUNDERSTORM POTENTIAL. POLAN
&&
.PREVIOUS AVIATION DISCUSSION...06Z TAFS. SCT-BKN 050-080 TONIGHT AS
A WEAK UPPER TROUGH IS MOVING THROUGH. SCT 050-080 SUNDAY. WINDS
5-15KT EXCEPT 10-20KT AT DLS. 94
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 70 44 76 49 / 10 0 0 0
ALW 71 49 79 53 / 10 0 0 0
PSC 76 43 81 48 / 10 0 0 0
YKM 74 44 78 46 / 10 0 0 0
HRI 75 43 80 47 / 10 0 0 0
ELN 71 45 79 46 / 10 0 0 0
RDM 66 32 75 44 / 10 0 0 0
LGD 64 39 73 45 / 20 0 0 0
GCD 64 40 74 42 / 10 0 0 0
DLS 71 46 80 51 / 10 0 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 190227
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
730 PM PDT SAT MAY 18 2013
.SHORT TERM...UPPER LEVEL TROUGH IS MOVING ACROSS THE REGION THIS
EVENING. SKIES ARE PARTLY TO MOSTLY CLOUDY WITH ISOLATED SHOWERS.
WITH LOSS OF HEATING AFTER SUNSET PRECIPITATION WILL DECREASE TO A
FEW SHOWERS OVER THE CASCADES AND BLUES. BREEZY WESTERLY WINDS WILL
ALSO DIMINISH OVERNIGHT. UPPER LEVEL RIDGE WILL RESULT IN MOSTLY
SUNNY SKIES AND WARMER TEMPERATURES SUNDAY AND MONDAY. 94
&&
.PREV DISCUSSION... /ISSUED 330 PM PDT SAT MAY 18 2013/
SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...A WEAK PACIFIC SYSTEM
WILL CONTINUE TO MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
THEN SHIFT SOUTHEAST ACROSS IDAHO AND WYOMING ON SUNDAY. WILL
CONTINUE TO SEE ISOLATED TO SCATTERED SHOWERS ACROSS MUCH OF THE
AREA THIS EVENING, WITH THE BEST CHANCES ACROSS CENTRAL AND
EAST-CENTRAL OREGON. THESE SHOWERS WILL GRADUALLY DECREASE LATE THIS
EVENING AND OVERNIGHT, WITH ONLY A FEW SHOWERS LINGERING OVER THE
MOUNTAINS TOWARDS DAYBREAK. THERE REMAINS ENOUGH INSTABILITY LATE
THIS AFTERNOON INTO EARLY THIS EVENING FOR STRAY THUNDERSTORMS OVER
THE SOUTHERN OREGON BLUE MOUNTAINS, THE JOHN DAY BASIN AND THE JOHN
DAY-OCHOCO HIGHLANDS. WINDS WILL CONTINUE BREEZY TO LOCALLY WINDY
ACROSS THE AREA THROUGH THIS EVENING, THEN GRADUALLY DECREASE
OVERNIGHT. LOCALLY BREEZY WINDS WILL CONTINUE THROUGH SUNDAY,
PRIMARILY IN AND NEAR THE COLUMBIA RIVER GORGE AND IN THE KITTITAS
VALLEY. LINGERING MOISTURE COMBINED WITH A NORTHWEST FLOW ALOFT WILL
KEEP A FEW SHOWERS GOING OVER SOME AREA MOUNTAINS SUNDAY THROUGH
SUNDAY EVENING DUE TO UPSLOPE AFFECTS. OTHERWISE HIGH PRESSURE ALOFT
AND AT THE SURFACE WILL BUILD INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THUS EXPECT DRY CONDITIONS LATE SUNDAY NIGHT THROUGH MONDAY
EVENING. HIGH TEMPS MONDAY WILL WARM 7-10 DEGREES OVER SUNDAY
AFTERNOON. AN APPROACHING PACIFIC SYSTEM MAY SPREAD SOME LIGHT
PRECIP TO THE WASHINGTON CASCADE CREST AREA LATE MONDAY NIGHT,
OTHERWISE SHOULD CONTINUED DRY CONDITIONS WITH INCREASING CLOUDS. 90
LONG TERM...TUESDAY THROUGH SATURDAY. CONFIDENCE IS HIGH THAT THE
PACIFIC NW WILL BE UNDER THE INFLUENCE OF A LARGE CLOSED LOW DURING
THE PERIOD. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE LOW
AND THE LOCATION/STRENGTH OF EMBEDDED SHORTWAVES IS LOW...ESPECIALLY
THURS-SAT. THE LARGE UPPER LOW WILL MOVE ONSHORE TUESDAY THEN WILL
BECOME BLOCKED BY AN AMPLIFIED RIDGE OVER THE MIDWEST. THIS COLD
LOW WILL RESULT IN UNSEASONABLY COLDER TEMPERATURES AND SHOWERY
CONDITIONS THROUGH THE EXTENDED PERIOD. SNOW LEVELS WILL LOWER
SIGNIFICANTLY LATE TUESDAY NIGHT AND WEDNESDAY MORNING...POSSIBLY AS
LOW AS 3500-4000 FEET. MODELS BEGIN TO DIVERGE ON THURSDAY. WHILE
THE ECMWF SWINGS THE LOW TO THE NORTHEAST ACROSS OREGON ON
FRIDAY...THE GFS IS FARTHER NORTH AND WEST WITH THE PRIMARY POSITION
OFFSHORE. EITHER WAY...THE PACIFIC NW WILL BE COOL AND SHOWERY
DURING THE LONG TERM PERIOD. WISTER
AVIATION...00Z TAFS. SCATTERED SHOWERS MAY CAUSE CIGS/VSBYS TO
BRIEFLY LOWER TO NEAR MVFR THIS AFTERNOON AND EVENING.
OTHERWISE...VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. CIGS
WILL RANGE FROM 4-8000 FEET AGL...ALTHOUGH THERE WILL BE BREAKS IN
THE CLOUD COVER OVERNIGHT. SKIES WILL BE SCT-BKN ON SUNDAY WITH
BASES AROUND 7-10,000 FEET AGL. SUSTAINED WINDS OF 10-15 KNOTS
GUSTING TO 25 KNOTS CAN BE EXPECTED IN MOST AREAS THIS
EVENING...DIMINISH OVERNIGHT...THEN INCREASE TO 5-15 KNOTS ON
SUNDAY. WISTER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 46 70 44 76 / 20 10 0 0
ALW 50 71 49 77 / 20 10 0 0
PSC 48 77 42 80 / 20 10 0 0
YKM 42 74 40 78 / 20 10 0 0
HRI 48 75 41 79 / 20 10 0 0
ELN 46 72 43 78 / 20 10 0 0
RDM 35 67 32 76 / 20 10 0 0
LGD 44 65 40 73 / 30 20 0 0
GCD 40 67 36 76 / 30 10 0 0
DLS 50 71 44 81 / 20 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SUNDAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
94
000
FXUS66 KPDT 182231 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
330 PM PDT SAT MAY 18 2013
UPDATED AVIATION DISCUSSION
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...A WEAK PACIFIC SYSTEM
WILL CONTINUE TO MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
THEN SHIFT SOUTHEAST ACROSS IDAHO AND WYOMING ON SUNDAY. WILL
CONTINUE TO SEE ISOLATED TO SCATTERED SHOWERS ACROSS MUCH OF THE
AREA THIS EVENING, WITH THE BEST CHANCES ACROSS CENTRAL AND
EAST-CENTRAL OREGON. THESE SHOWERS WILL GRADUALLY DECREASE LATE THIS
EVENING AND OVERNIGHT, WITH ONLY A FEW SHOWERS LINGERING OVER THE
MOUNTAINS TOWARDS DAYBREAK. THERE REMAINS ENOUGH INSTABILITY LATE
THIS AFTERNOON INTO EARLY THIS EVENING FOR STRAY THUNDERSTORMS OVER
THE SOUTHERN OREGON BLUE MOUNTAINS, THE JOHN DAY BASIN AND THE JOHN
DAY-OCHOCO HIGHLANDS. WINDS WILL CONTINUE BREEZY TO LOCALLY WINDY
ACROSS THE AREA THROUGH THIS EVENING, THEN GRADUALLY DECREASE
OVERNIGHT. LOCALLY BREEZY WINDS WILL CONTINUE THROUGH SUNDAY,
PRIMARILY IN AND NEAR THE COLUMBIA RIVER GORGE AND IN THE KITTITAS
VALLEY. LINGERING MOISTURE COMBINED WITH A NORTHWEST FLOW ALOFT WILL
KEEP A FEW SHOWERS GOING OVER SOME AREA MOUNTAINS SUNDAY THROUGH
SUNDAY EVENING DUE TO UPSLOPE AFFECTS. OTHERWISE HIGH PRESSURE ALOFT
AND AT THE SURFACE WILL BUILD INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THUS EXPECT DRY CONDITIONS LATE SUNDAY NIGHT THROUGH MONDAY
EVENING. HIGH TEMPS MONDAY WILL WARM 7-10 DEGREES OVER SUNDAY
AFTERNOON. AN APPROACHING PACIFIC SYSTEM MAY SPREAD SOME LIGHT
PRECIP TO THE WASHINGTON CASCADE CREST AREA LATE MONDAY NIGHT,
OTHERWISE SHOULD CONTINUED DRY CONDITIONS WITH INCREASING CLOUDS. 90
.LONG TERM...TUESDAY THROUGH SATURDAY. CONFIDENCE IS HIGH THAT THE
PACIFIC NW WILL BE UNDER THE INFLUENCE OF A LARGE CLOSED LOW DURING
THE PERIOD. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE LOW
AND THE LOCATION/STRENGTH OF EMBEDDED SHORTWAVES IS LOW...ESPECIALLY
THURS-SAT. THE LARGE UPPER LOW WILL MOVE ONSHORE TUESDAY THEN WILL
BECOME BLOCKED BY AN AMPLIFIED RIDGE OVER THE MIDWEST. THIS COLD
LOW WILL RESULT IN UNSEASONABLY COLDER TEMPERATURES AND SHOWERY
CONDITIONS THROUGH THE EXTENDED PERIOD. SNOW LEVELS WILL LOWER
SIGNIFICANTLY LATE TUESDAY NIGHT AND WEDNESDAY MORNING...POSSIBLY AS
LOW AS 3500-4000 FEET. MODELS BEGIN TO DIVERGE ON THURSDAY. WHILE
THE ECMWF SWINGS THE LOW TO THE NORTHEAST ACROSS OREGON ON
FRIDAY...THE GFS IS FARTHER NORTH AND WEST WITH THE PRIMARY POSITION
OFFSHORE. EITHER WAY...THE PACIFIC NW WILL BE COOL AND SHOWERY
DURING THE LONG TERM PERIOD. WISTER
&&
.AVIATION...00Z TAFS. SCATTERED SHOWERS MAY CAUSE CIGS/VSBYS TO
BRIEFLY LOWER TO NEAR MVFR THIS AFTERNOON AND EVENING.
OTHERWISE...VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. CIGS
WILL RANGE FROM 4-8000 FEET AGL...ALTHOUGH THERE WILL BE BREAKS IN
THE CLOUD COVER OVERNIGHT. SKIES WILL BE SCT-BKN ON SUNDAY WITH
BASES AROUND 7-10,000 FEET AGL. SUSTAINED WINDS OF 10-15 KNOTS
GUSTING TO 25 KNOTS CAN BE EXPECTED IN MOST AREAS THIS
EVENING...DIMINISH OVERNIGHT...THEN INCREASE TO 5-15 KNOTS ON
SUNDAY. WISTER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 46 70 44 76 / 20 10 0 0
ALW 50 71 49 77 / 20 10 0 0
PSC 48 77 42 80 / 10 10 0 0
YKM 42 74 40 78 / 10 10 0 0
HRI 48 75 41 79 / 20 10 0 0
ELN 46 72 43 78 / 10 10 0 0
RDM 35 67 32 76 / 20 10 0 0
LGD 44 65 40 73 / 20 20 0 0
GCD 40 67 36 76 / 30 10 0 0
DLS 50 71 44 81 / 20 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SUNDAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/85/85
000
FXUS66 KPDT 182149
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
249 PM PDT SAT MAY 18 2013
.SHORT TERM...TONIGHT THROUGH MONDAY NIGHT...A WEAK PACIFIC SYSTEM
WILL CONTINUE TO MOVE ACROSS THE REGION TONIGHT. THIS SYSTEM WILL
THEN SHIFT SOUTHEAST ACROSS IDAHO AND WYOMING ON SUNDAY. WILL
CONTINUE TO SEE ISOLATED TO SCATTERED SHOWERS ACROSS MUCH OF THE
AREA THIS EVENING, WITH THE BEST CHANCES ACROSS CENTRAL AND
EAST-CENTRAL OREGON. THESE SHOWERS WILL GRADUALLY DECREASE LATE THIS
EVENING AND OVERNIGHT, WITH ONLY A FEW SHOWERS LINGERING OVER THE
MOUNTAINS TOWARDS DAYBREAK. THERE REMAINS ENOUGH INSTABILITY LATE
THIS AFTERNOON INTO EARLY THIS EVENING FOR STRAY THUNDERSTORMS OVER
THE SOUTHERN OREGON BLUE MOUNTAINS, THE JOHN DAY BASIN AND THE JOHN
DAY-OCHOCO HIGHLANDS. WINDS WILL CONTINUE BREEZY TO LOCALLY WINDY
ACROSS THE AREA THROUGH THIS EVENING, THEN GRADUALLY DECREASE
OVERNIGHT. LOCALLY BREEZY WINDS WILL CONTINUE THROUGH SUNDAY,
PRIMARILY IN AND NEAR THE COLUMBIA RIVER GORGE AND IN THE KITTITAS
VALLEY. LINGERING MOISTURE COMBINED WITH A NORTHWEST FLOW ALOFT WILL
KEEP A FEW SHOWERS GOING OVER SOME AREA MOUNTAINS SUNDAY THROUGH
SUNDAY EVENING DUE TO UPSLOPE AFFECTS. OTHERWISE HIGH PRESSURE ALOFT
AND AT THE SURFACE WILL BUILD INTO THE REGION SUNDAY NIGHT INTO
MONDAY. THUS EXPECT DRY CONDITIONS LATE SUNDAY NIGHT THROUGH MONDAY
EVENING. HIGH TEMPS MONDAY WILL WARM 7-10 DEGREES OVER SUNDAY
AFTERNOON. AN APPROACHING PACIFIC SYSTEM MAY SPREAD SOME LIGHT
PRECIP TO THE WASHINGTON CASCADE CREST AREA LATE MONDAY NIGHT,
OTHERWISE SHOULD CONTINUED DRY CONDITIONS WITH INCREASING CLOUDS. 90
.LONG TERM...TUESDAY THROUGH SATURDAY. CONFIDENCE IS HIGH THAT THE
PACIFIC NW WILL BE UNDER THE INFLUENCE OF A LARGE CLOSED LOW DURING
THE PERIOD. HOWEVER...CONFIDENCE IN THE EXACT PLACEMENT OF THE LOW
AND THE LOCATION/STRENGTH OF EMBEDDED SHORTWAVES IS LOW...ESPECIALLY
THURS-SAT. THE LARGE UPPER LOW WILL MOVE ONSHORE TUESDAY THEN WILL
BECOME BLOCKED BY AN AMPLIFIED RIDGE OVER THE MIDWEST. THIS COLD
LOW WILL RESULT IN UNSEASONABLY COLDER TEMPERATURES AND SHOWERY
CONDITIONS THROUGH THE EXTENDED PERIOD. SNOW LEVELS WILL LOWER
SIGNIFICANTLY LATE TUESDAY NIGHT AND WEDNESDAY MORNING...POSSIBLY AS
LOW AS 3500-4000 FEET. MODELS BEGIN TO DIVERGE ON THURSDAY. WHILE
THE ECMWF SWINGS THE LOW TO THE NORTHEAST ACROSS OREGON ON
FRIDAY...THE GFS IS FARTHER NORTH AND WEST WITH THE PRIMARY POSITION
OFFSHORE. AT THIS TIME...I`M LEANING TOWARDS THE ECMWF WHICH IS
CLOSER TO THE ENSEMBLE RUNS. EITHER WAY...THE PACIFIC NW WILL BE
COOL AND SHOWERY DURING THE LONG TERM PERIOD. WISTER
&&
.AVIATION...PREVIOUS DISCUSSION...18Z TAFS. SCATTERED SHOWERS MAY
BRIEFLY CAUSE CIGS TO LOWER TO NEAR MVFR THIS AFTERNOON AND
EVENING. OTHERWISE...VFR CONDITIONS WILL PREVAIL FOR THE NEXT 24
HOURS. CIGS WILL RANGE FROM 4-8000 FEET AGL...ALTHOUGH THERE WILL BE
BREAKS IN THE CLOUD COVER OVERNIGHT. SUSTAINED WINDS OF 10-20 KNOTS
CAN BE EXPECTED IN MOST AREAS. WISTER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 46 70 44 76 / 20 10 0 0
ALW 50 71 49 77 / 20 10 0 0
PSC 48 77 42 80 / 10 10 0 0
YKM 42 74 40 78 / 10 10 0 0
HRI 48 75 41 79 / 20 10 0 0
ELN 46 72 43 78 / 10 10 0 0
RDM 35 67 32 76 / 20 10 0 0
LGD 44 65 40 73 / 20 20 0 0
GCD 40 67 36 76 / 30 10 0 0
DLS 50 71 44 81 / 20 10 0 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SUNDAY : GREEN
MONDAY : GREEN
TUESDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/85/85
000
FXUS66 KPDT 181731 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
1035 AM PDT SAT MAY 18 2013
UPDATED AVIATION DISCUSSION
.SHORT TERM...UPDATE...A WEAK PACIFIC SYSTEM WILL MOVE ACROSS THE
REGION TODAY AND TONIGHT. WILL SEE CLOUDS INCREASE AND THICKEN
ACROSS THE AREA THIS MORNING INTO EARLY AFTERNOON. ALSO ISOLATED TO
SCATTERED SHOWERS WILL SPREAD ACROSS THE AREA, WITH THE BEST CHANCES
ACROSS CENTRAL AND EAST-CENTRAL OREGON. ALSO EXPECT SCATTERED
SHOWERS OVER THE MOUNTAINS WITH LOCALLY NUMEROUS SHOWERS ALONG THE
CASCADE CREST. MAY SEE ENOUGH INSTABILITY LATE THIS AFTERNOON INTO
EARLY THIS EVENING FOR STRAY THUNDERSTORMS OVER THE SOUTHERN OREGON
BLUE MOUNTAINS, THE JOHN DAY BASIN AND THE JOHN DAY-OCHOCO
HIGHLANDS. WINDS WILL BE BREEZY TO LOCALLY WINDY ACROSS THE AREA
THROUGH TODAY INTO THIS EVENING. UPDATES THIS MORNING INCLUDED
ADDING MENTION OF ISOLATED THUNDERSTORMS IN THE AREAS LISTED ABOVE,
AS WELL AS MAKING ADJUSTMENTS TO THE OTHER FORECAST PARAMETERS BASED
ON CURRENT TRENDS. 90
.LONG TERM...PREVIOUS DISCUSSION...MONDAY MORNING A LARGE MID/UPPER
LEVEL TROUGH MOVES SOUTHEAST ALONG THE SE ALASKAN ARCHIPELAGO AND
COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST NEAR 45N/135W IN
THE SOUTHERN JETSTREAM. DURING THE DAY ON MONDAY THESE TWO SYSTEMS
MERGE WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD INTO THE
EASTERN FLANK OF THE MID/UPPER TROUGH MOVING SOUTHEAST NEAR QUEEN
CHARLOTTE ISLAND.
TUESDAY THE LARGE UPPER TROUGH TRANSFORMS INTO A LARGE MID/UPPER
LEVEL LOW. THE LOW CONTINUES MOVING SOUTHEAST WITH THE CENTER OF THE
LOW APPROACHING THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE
TUESDAY AFTERNOON. THIS WILL CAUSE A SOUTHWEST FLOW ALOFT TO BACK
MORE TO THE SOUTH OVER THE FORECAST AREA AND TRANSPORT MOISTURE AND
INSTABILITY INTO THE REGION. THE COLD UPPER LOW WILL USHER IN A
COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE UPPER
LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH FRIDAY.
THE GFS AND ECMWF MODEL RUNS SHOW BETTER AGREEMENT FOR TUESDAY
THROUGH FRIDAY IN TERMS OF THE PLACEMENT OF THE UPPER LOW. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS. BUT WILL REFRAIN
FROM INTRODUCING A SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY SINCE
THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL COVERAGE OF
THUNDERSTORM POTENTIAL.
&&
.AVIATION...18Z TAFS. SCATTERED SHOWERS MAY BRIEFLY CAUSE CIGS TO
LOWER TO NEAR MVFR THIS AFTERNOON AND EVENING. OTHERWISE...VFR
CONDITIONS WILL PREVAIL FOR THE NEXT 24 HOURS. CIGS WILL RANGE FROM
4-8000 FEET AGL...ALTHOUGH THERE WILL BE BREAKS IN THE CLOUD COVER
OVERNIGHT. SUSTAINED WINDS OF 10-20 KNOTS CAN BE EXPECTED IN MOST
AREAS. WISTER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 66 45 68 42 / 20 20 10 0
ALW 69 51 69 46 / 20 20 10 0
PSC 74 50 74 44 / 20 10 10 0
YKM 70 48 72 45 / 20 10 10 0
HRI 72 49 72 43 / 20 20 10 0
ELN 68 47 69 42 / 20 10 10 0
RDM 63 35 63 29 / 30 20 10 0
LGD 62 45 62 39 / 20 20 20 0
GCD 65 43 63 38 / 30 30 10 10
DLS 68 50 68 44 / 20 20 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/99/85
000
FXUS66 KPDT 181637
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
935 AM PDT SAT MAY 18 2013
.SHORT TERM...UPDATE...A WEAK PACIFIC SYSTEM WILL MOVE ACROSS THE
REGION TODAY AND TONIGHT. WILL SEE CLOUDS INCREASE AND THICKEN
ACROSS THE AREA THIS MORNING INTO EARLY AFTERNOON. ALSO ISOLATED TO
SCATTERED SHOWERS WILL SPREAD ACROSS THE AREA, WITH THE BEST CHANCES
ACROSS CENTRAL AND EAST-CENTRAL OREGON. ALSO EXPECT SCATTERED
SHOWERS OVER THE MOUNTAINS WITH LOCALLY NUMEROUS SHOWERS ALONG THE
CASCADE CREST. MAY SEE ENOUGH INSTABILITY LATE THIS AFTERNOON INTO
EARLY THIS EVENING FOR STRAY THUNDERSTORMS OVER THE SOUTHERN OREGON
BLUE MOUNTAINS, THE JOHN DAY BASIN AND THE JOHN DAY-OCHOCO
HIGHLANDS. WINDS WILL BE BREEZY TO LOCALLY WINDY ACROSS THE AREA
THROUGH TODAY INTO THIS EVENING. UPDATES THIS MORNING INCLUDED
ADDING MENTION OF ISOLATED THUNDERSTORMS IN THE AREAS LISTED ABOVE,
AS WELL AS MAKING ADJUSTMENTS TO THE OTHER FORECAST PARAMETERS BASED
ON CURRENT TRENDS. 90
.LONG TERM...PREVIOUS DISCUSSION...MONDAY MORNING A LARGE MID/UPPER
LEVEL TROUGH MOVES SOUTHEAST ALONG THE SE ALASKAN ARCHIPELAGO AND
COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST NEAR 45N/135W IN
THE SOUTHERN JETSTREAM. DURING THE DAY ON MONDAY THESE TWO SYSTEMS
MERGE WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD INTO THE
EASTERN FLANK OF THE MID/UPPER TROUGH MOVING SOUTHEAST NEAR QUEEN
CHARLOTTE ISLAND.
TUESDAY THE LARGE UPPER TROUGH TRANSFORMS INTO A LARGE MID/UPPER
LEVEL LOW. THE LOW CONTINUES MOVING SOUTHEAST WITH THE CENTER OF THE
LOW APPROACHING THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE
TUESDAY AFTERNOON. THIS WILL CAUSE A SOUTHWEST FLOW ALOFT TO BACK
MORE TO THE SOUTH OVER THE FORECAST AREA AND TRANSPORT MOISTURE AND
INSTABILITY INTO THE REGION. THE COLD UPPER LOW WILL USHER IN A
COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE UPPER
LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH FRIDAY.
THE GFS AND ECMWF MODEL RUNS SHOW BETTER AGREEMENT FOR TUESDAY
THROUGH FRIDAY IN TERMS OF THE PLACEMENT OF THE UPPER LOW. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS. BUT WILL REFRAIN
FROM INTRODUCING A SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY SINCE
THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL COVERAGE OF
THUNDERSTORM POTENTIAL.
&&
.AVIATION...PREVIOUS DISCUSSION...12Z TAFS...VFR CONDITIONS ARE
EXPECTED OVER THE NEXT 24 HOURS. THERE MAY BE BRIEF MVFR CONDITIONS
AT KRDM AND KBDN DUE TO SHOWERS AFTER 18Z. OTHERWISE, CIGS WILL BE
SCT TO BKN 5000 FT AND BKN TO OVC 10000 FT THROUGH 03Z/19TH WITH
CONDITIONS GRADUALLY IMPROVING. WINDS WILL BE BETWEEN 5-15 KTS
GUSTING TO 25 KTS AT TIMES IN THE AFTERNOON.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 66 45 68 42 / 20 20 10 0
ALW 69 51 69 46 / 20 20 10 0
PSC 74 50 74 44 / 20 10 10 0
YKM 70 48 72 45 / 20 10 10 0
HRI 72 49 72 43 / 20 20 10 0
ELN 68 47 69 42 / 20 10 10 0
RDM 63 35 63 29 / 30 20 10 0
LGD 62 45 62 39 / 20 20 20 0
GCD 65 43 63 38 / 30 30 10 10
DLS 68 50 68 44 / 20 20 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
90/99/85
000
FXUS66 KPDT 181051 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
351 AM PDT SAT MAY 18 2013
UPDATED AVIATION AND LONG TERM DISCUSSIONS
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT...ONE WAVE IS MOVING
THROUGH WALLOWA COUNTY AND THE NORTHERN BLUES THIS MORNING WHILE
ANOTHER ONE IS APPROACHING THE COAST. 6Z NAM INDICATES THE FIRST
WAVE WILL BE OUT OF THE CWA BY 12Z..BUT SOME OF THE SHOWERS MAY
LINGER INTO THE MORNING FORECAST TIME. I MIGHT MAKE A LATE
ADJUSTMENT BASED ON LATEST RADAR. CURRENT RADAR INDICATES THAT
PRECIPITATION AHEAD OF THE SECOND WAVE IS APPROACHING THE
CASCADES..SO THERE WILL BE SOME SLOP OVER MORNING PRECIPITATION
THERE AS WELL. ISOLATED TO SCATTERED SHOWERS WILL DEVELOP WITH
DAYTIME HEATING AGAIN THIS AFTERNOON ACROSS SOUTHEAST WASHINGTON AND
EASTERN OREGON. INSTABILITY INDICATED BY NEGATIVE LIS AND MUCAPE IS
MAINLY SOUTH OF THE CWA SO I DID NOT INCLUDE ANY THUNDERSTORMS IN
THE FORECAST THIS AFTERNOON. THE SECOND WAVE WILL MOVE EAST OF THE
CASCADES EARLY THIS EVENING. THERE WILL BE SOME CLEARING BEHIND THIS
WAVE IN THE WESTERN HALF OF THE CWA OVERNIGHT...BUT SHOWERS WILL
PERSIST FROM GRANT COUNTY TO THE NORTHERN BLUES AND WALLOWA COUNTY
OVERNIGHT DUE TO THIS WAVE. AN UPPER LEVEL RIDGE WILL BUILD ALONG
THE COAST SUNDAY. THIS WILL BRING A DRIER NORTHWEST FLOW TO EASTERN
WASHINGTON AND OREGON. ENOUGH MOISTURE MAY LINGER FROM GRANT COUNTY
TO THE NORTHERN BLUES AND WALLOWA COUNTY FOR A FEW SHOWERS TO
DEVELOP WITH AFTERNOON HEATING. THE RIDGE AXIS WILL MOVE INTO
EASTERN WASHINGTON AND OREGON SUNDAY NIGHT WITH CLEARING SKIES. THIS
WILL ALLOW RADIATIONAL COOLING WITH COOLER OVERNIGHT TEMPERATURES.
COONFIELD
.LONG TERM...MONDAY THROUGH FRIDAY...MONDAY MORNING A LARGE
MID/UPPER LEVEL TROUGH MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/135W IN THE SOUTHERN JETSTREAM. DURING THE DAY ON MONDAY
THESE TWO SYSTEMS MERGE WITH THE SOUTHERN SYSTEM PULLING MOISTURE
NORTHWARD INTO THE EASTERN FLANK OF THE MID/UPPER TROUGH MOVING
SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
TUESDAY THE LARGE UPPER TROUGH TRANSFORMS INTO A LARGE MID/UPPER
LEVEL LOW. THE LOW CONTINUES MOVING SOUTHEAST WITH THE CENTER OF THE
LOW APPROACHING THE COAST JUST WEST OF THE COLUMBIA RIVER BY LATE
TUESDAY AFTERNOON. THIS WILL CAUSE A SOUTHWEST FLOW ALOFT TO BACK
MORE TO THE SOUTH OVER THE FORECAST AREA AND TRANSPORT MOISTURE AND
INSTABILITY INTO THE REGION. THE COLD UPPER LOW WILL USHER IN A
COOLING TREND AND PERIODS OF UNSETTLED SHOWERY WEATHER, AS THE UPPER
LOW CENTER MOVES OVER THE FORECAST AREA AND PERSISTS THROUGH FRIDAY.
THE GFS AND ECMWF MODEL RUNS SHOW BETTER AGREEMENT FOR TUESDAY
THROUGH FRIDAY IN TERMS OF THE PLACEMENT OF THE UPPER LOW. DAYTIME
HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN NORMAL FOR TUESDAY
THROUGH FRIDAY.
TEMPERATURE LAPSE RATES FROM 5000 FT TO 20000 FT IN THE MID LEVELS
OF THE ATMOSPHERE OF SEVEN DEGREES CELSIUS OR LARGER SUGGEST THAT
THERE MAY BE ENOUGH MARGINAL INSTABILITY, COMBINED WITH VERY STRONG
DYNAMIC LIFT AND VERTICAL WIND SHEAR OF 40 TO 60 KNOTS FROM THE
SURFACE TO 20000 FT, WHICH WOULD FAVOR DEVELOPMENT OF A FEW ISOLATED
THUNDERSTORMS DURING THE DAYTIME ON WEDNESDAY, ESPECIALLY IN THE
AFTERNOON AND EARLY EVENING OVER THE MOUNTAINS. BUT WILL REFRAIN
FROM INTRODUCING A SLIGHT CHANCE OF THUNDERSTORMS ON WEDNESDAY SINCE
THIS FAR OUT CONFIDENCE IS LOW WITH RESPECT TO AREAL COVERAGE OF
THUNDERSTORM POTENTIAL. POLAN
&&
.AVIATION...12Z TAFS...VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24
HOURS. THERE MAY BE BRIEF MVFR CONDITIONS AT KRDM AND KBDN DUE TO
SHOWERS AFTER 18Z. OTHERWISE, CIGS WILL BE SCT TO BKN 5000 FT AND
BKN TO OVC 10000 FT THROUGH 03Z/19TH WITH CONDITIONS GRADUALLY
IMPROVING. WINDS WILL BE BETWEEN 5-15 KTS GUSTING TO 25 KTS AT TIMES
IN THE AFTERNOON. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 66 45 68 42 / 20 20 10 0
ALW 69 51 69 46 / 20 20 10 0
PSC 74 50 74 44 / 20 10 10 0
YKM 70 48 72 45 / 20 10 10 0
HRI 72 49 72 43 / 20 10 10 0
ELN 68 47 69 42 / 20 10 10 0
RDM 63 35 63 29 / 30 20 10 0
LGD 62 45 62 39 / 20 20 20 0
GCD 62 43 63 38 / 30 20 10 10
DLS 66 50 68 44 / 20 20 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 181004
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
304 AM PDT SAT MAY 18 2013
.SHORT TERM...TODAY THROUGH SUNDAY NIGHT...ONE WAVE IS MOVING
THROUGH WALLOWA COUNTY AND THE NORTHERN BLUES THIS MORNING WHILE
ANOTHER ONE IS APPROACHING THE COAST. 6Z NAM INDICATES THE FIRST
WAVE WILL BE OUT OF THE CWA BY 12Z..BUT SOME OF THE SHOWERS MAY
LINGER INTO THE MORNING FORECAST TIME. I MIGHT MAKE A LATE
ADJUSTMENT BASED ON LATEST RADAR. CURRENT RADAR INDICATES THAT
PRECIPITATION AHEAD OF THE SECOND WAVE IS APPROACHING THE
CASCADES..SO THERE WILL BE SOME SLOP OVER MORNING PRECIPITATION
THERE AS WELL. ISOLATED TO SCATTERED SHOWERS WILL DEVELOP WITH
DAYTIME HEATING AGAIN THIS AFTERNOON ACROSS SOUTHEAST WASHINGTON AND
EASTERN OREGON. INSTABILITY INDICATED BY NEGATIVE LIS AND MUCAPE IS
MAINLY SOUTH OF THE CWA SO I DID NOT INCLUDE ANY THUNDERSTORMS IN
THE FORECAST THIS AFTERNOON. THE SECOND WAVE WILL MOVE EAST OF THE
CASCADES EARLY THIS EVENING. THERE WILL BE SOME CLEARING BEHIND THIS
WAVE IN THE WESTERN HALF OF THE CWA OVERNIGHT...BUT SHOWERS WILL
PERSIST FROM GRANT COUNTY TO THE NORTHERN BLUES AND WALLOWA COUNTY
OVERNIGHT DUE TO THIS WAVE. AN UPPER LEVEL RIDGE WILL BUILD ALONG
THE COAST SUNDAY. THIS WILL BRING A DRIER NORTHWEST FLOW TO EASTERN
WASHINGTON AND OREGON. ENOUGH MOISTURE MAY LINGER FROM GRANT COUNTY
TO THE NORTHERN BLUES AND WALLOWA COUNTY FOR A FEW SHOWERS TO
DEVELOP WITH AFTERNOON HEATING. THE RIDGE AXIS WILL MOVE INTO
EASTERN WASHINGTON AND OREGON SUNDAY NIGHT WITH CLEARING SKIES. THIS
WILL ALLOW RADIATIONAL COOLING WITH COOLER OVERNIGHT TEMPERATURES.
COONFIELD
.LONG TERM...MONDAY THROUGH FRIDAY...MONDAY MORNING A LARGE
MID/UPPER LEVEL TROUGH MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/135W IN THE SOUTHERN JETSTREAM. DURING THE DAY ON MONDAY
THESE TWO SYSTEMS MERGE WITH THE SOUTHERN SYSTEM PULLING MOISTURE
NORTHWARD INTO THE EASTERN FLANK OF THE MID/UPPER TROUGH MOVING
SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
TUESDAY THE LARGE UPPER LOW CONTINUES MOVING SOUTHEAST WITH THE
CENTER OF THE LOW ARRIVING ON THE COAST JUST NORTH OF THE COLUMBIA
RIVER BY TUESDAY AFTERNOON. THIS WILL CAUSE A SOUTHWEST FLOW ALOFT
TO BACK TO THE SOUTH OVER THE INTERIOR PACIFIC NORTHWEST AND
TRANSPORT MOISTURE AND INCREASING INSTABILITY INTO THE REGION. THE
APPROACHING COLD UPPER LOW WILL USHER IN A COOLING TREND, AS THE
UPPER LOW CENTER COMES NEARER TO THE FORECAST AREA. THE UPPER LOW
WILL PERSIST OVER THE PACIFIC NORTHWEST THROUGH THURSDAY. HOWEVER,
FROM ONE RUN TO THE NEXT, THE GFS AND ECMWF SOLUTIONS ARE EXHIBITING
SIGNIFICANT DIFFERENCES IN THE PLACEMENT OF THE CENTER OF THE UPPER
LOW, AND A COMPARISON OF THE PLACEMENT OF THE CENTER OF THE UPPER
LOW BETWEEN THE GFS AND ECMWF MODELS FOR A GIVEN FORECAST BASE TIME
LIKEWISE SHOW SIGNIFICANT DIFFERENCES. AS SUCH UNCERTAINTY IN THE
FORECAST IS GREATER THAN NORMAL FOR TUESDAY THROUGH FRIDAY IN TERMS
OF LARGE STANDARD DEVIATIONS IN THE OVERALL 500MB HEIGHT PATTERN IN
BOTH MODELS. HOWEVER, WITH EACH ADDITIONAL MODEL RUN, THE GFS AND
ECMWF MODELS ARE DISPLAYING BETTER AGREEMENT FOR TUESDAY THROUGH
FRIDAY. EXPECT COOL AND UNSETTLED CONDITIONS WITH PERIODS OF SHOWERS
EACH DAY FROM TUESDAY THROUGH THURSDAY. THE UPPER LOW PERSISTS OVER
THE INTERIOR PACIFIC NORTHWEST THROUGH FRIDAY THUS RESULTING IN
DAYTIME HIGH TEMPERATURES BEING SLIGHTLY COOLER THAN NORMAL. POLAN
&&
.AVIATION...06Z TAFS...VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24
HOURS. THERE MAY BE BRIEF MVFR CONDITIONS AT KRDM AND KBDN DUE TO
SHOWERS AFTER 18Z. OTHERWISE CIGS WILL BE SCT TO BKN 5KFT AND BKN
TO OVC 10KFT THROUGH 03Z WITH CONDITIONS GRADUALLY IMPROVING. WINDS
WILL BE BETWEEN 5-15KTS GUSTING TO 25KTS AT TIMES. WEBER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 66 45 68 42 / 20 20 10 0
ALW 69 51 69 46 / 20 20 10 0
PSC 74 50 74 44 / 20 10 10 0
YKM 70 48 72 45 / 20 10 10 0
HRI 72 49 72 43 / 20 10 10 0
ELN 68 47 69 42 / 20 10 10 0
RDM 63 35 63 29 / 30 20 10 0
LGD 62 45 62 39 / 20 20 20 0
GCD 62 43 63 38 / 30 20 10 10
DLS 66 50 68 44 / 20 20 10 0
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 180545 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON
1045 PM PDT FRI MAY 17 2013
UPDATED FOR AVIATION DISCUSSION
.UPDATE...ISOLATED SHOWERS REMAIN ALONG THE FOOTHILLS OF THE BLUE
MOUNTAINS AND PORTIONS OF NORTHEAST OREGON BUT NO THUNDER
ASSOCIATED. EXPECT THESE SHOWERS TO DIMINISH OVER THE NEXT COUPLE
OF HOURS. WONT STILL RULE OUT A SLIGHT CHANCE OF A SHOWER OR TWO
OVERNIGHT FOR THE MOUNTAINS AREAS. SO HAVE KEPT A SLIGHT CHANCE
ACROSS THE HIGHER ELEVATIONS. MODELS CONTINUE TO BACK OFF ON THE
INSTABILITY TO SUPPORT THUNDER TOMORROW. RIGHT NOW SOUTH CENTRAL
PORTIONS OF OREGON LOOK TO HAVE THE BEST CHANCE FOR THUNDER...AND
EVEN IN THOSE AREAS IT LOOKS TO BE ISOLATED. WEBER
&&
.AVIATION...06Z TAFS...VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24
HOURS. THERE MAY BE BRIEF MVFR CONDITIONS AT KRDM AND KBDN DUE TO
SHOWERS AFTER 18Z. OTHERWISE CIGS WILL BE SCT TO BKN 5KFT AND BKN
TO OVC 10KFT THROUGH 03Z WITH CONDITIONS GRADUALLY IMPROVING. WINDS
WILL BE BETWEEN 5-15KTS GUSTING TO 25KTS AT TIMES. WEBER
&&
.PREV DISCUSSION... /ISSUED 220 PM PDT FRI MAY 17 2013/
SHORT TERM...TONIGHT THROUGH MONDAY...A WEATHER DISTURBANCE
CONTINUES TO MOVE ACROSS THE FORECAST AREA THIS AFTERNOON. THERE
WERE LIGHT RAIN SHOWERS REPORTED ACROSS THE BLUE MOUNTAIN FOOTHILLS
AND THE LOWER COLUMBIA BASIN...BUT PRECIPITATION AMOUNTS WERE MAINLY
JUST TRACE AMOUNTS. THE UPPER TROUGH ASSOCIATED WITH THIS SYSTEM IS
NOW LOCATED OVER THE CWA AND IT WILL SLOWLY LIFT OUT TO THE
NORTHEAST TONIGHT. ON SATURDAY ANOTHER WEATHER DISTURBANCE WILL MOVE
INTO THE REGION BRINGING ANOTHER CHANCE OF LIGHT RAIN SHOWERS...
MAINLY TO THE MOUNTAINS...HOWEVER CANNOT RULE OUT A LIGHT SPRINKLE
ELSEWHERE. AGAIN PRECIPITATION AMOUNTS WILL BE VERY LIGHT. THE UPPER
TROUGH WITH THIS NEXT SYSTEM WILL MOVE ACROSS THE CWA LATE SATURDAY
AFTERNOON AND EVENING. BEHIND IT AN UPPER RIDGE WILL BEGIN TO BUILD
INTO THE REGION WITH A DRIER NORTHWEST FLOW ALOFT BEGINNING BY LATE
SUNDAY. THIS UPPER RIDGE WILL PERSIST THROUGH MONDAY EVENING. EXPECT
WARMER TEMPERATURES ON MONDAY AS A RESULT WITH MAXIMUM TEMPERATURE
READINGS CLIMBING BACK INTO THE MID 70S IN THE LOWER ELEVATIONS AND
MID 50S TO MID 60S IN THE MOUNTAINS. THIS WILL BE SLIGHTLY ABOVE
NORMAL. A LARGE UPPER TROUGH WILL THEN SWING DOWN FROM THE GULF OF
ALASKA GOING INTO THE EXTENDED PERIOD WITH COOLER CONDITIONS AND
MORE CHANCES OF PRECIPITATION. 88
LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A RIDGE OF HIGH
PRESSURE SHOULD BRING A WARMER AND MAINLY DRY DAY FOR MONDAY. A
DISTURBANCE WILL APPROACH THE TWO STATE AREA MONDAY NIGHT THAT COULD
SPREAD SOME SHOWERS ALONG THE WA/OR CASCADES. AS A STRONG LOW
PRESSURE SYSTEM DIPS TOWARD THE PACNW TUESDAY...THE SHOWERS SHOULD
MOVE INTO THE REMAINDER OF THE REGION. THE LOW PRESSURE REMAINS
NEARLY STATIONARY AND KEEPS THE CLOUDS AND SHOWERS ALONG WITH THE
COOL TEMPERATURES ACROSS THE TWO STATE AREA THROUGH THURSDAY. THE
LOW IS FORECAST TO DRIFT NORTH AND SOME DRYING IS POSSIBLE FOR
FRIDAY AND SATURDAY ALONG WITH SLIGHTLY WARMER TEMPERATURES.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 42 66 40 67 / 20 20 20 10
ALW 48 68 45 67 / 20 20 20 10
PSC 48 73 45 72 / 10 20 10 10
YKM 44 68 42 70 / 10 20 10 10
HRI 46 70 45 70 / 10 20 10 10
ELN 45 66 43 66 / 10 20 10 10
RDM 37 61 30 60 / 10 30 20 10
LGD 40 62 40 60 / 30 20 20 20
GCD 41 59 36 61 / 20 30 20 10
DLS 48 65 45 65 / 10 20 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SATURDAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
89/97/89
000
FXUS66 KPDT 180321
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON
820 PM PDT FRI MAY 17 2013
.UPDATE...ISOLATED SHOWERS REMAIN ALONG THE FOOTHILLS OF THE BLUE
MOUNTAINS AND PORTIONS OF NORTHEAST OREGON BUT NO THUNDER
ASSOCIATED. EXPECT THESE SHOWERS TO DIMINISH OVER THE NEXT COUPLE
OF HOURS. WONT STILL RULE OUT A SLIGHT CHANCE OF A SHOWER OR TWO
OVERNIGHT FOR THE MOUNTAINS AREAS. SO HAVE KEPT A SLIGHT CHANCE
ACROSS THE HIGHER ELEVATIONS. MODELS CONTINUE TO BACK OFF ON THE
INSTABILITY TO SUPPORT THUNDER TOMORROW. RIGHT NOW SOUTH CENTRAL
PORTIONS OF OREGON LOOK TO HAVE THE BEST CHANCE FOR THUNDER...AND
EVEN IN THOSE AREAS IT LOOKS TO BE ISOLATED. WEBER
&&
.PREV DISCUSSION... /ISSUED 220 PM PDT FRI MAY 17 2013/
SHORT TERM...TONIGHT THROUGH MONDAY...A WEATHER DISTURBANCE
CONTINUES TO MOVE ACROSS THE FORECAST AREA THIS AFTERNOON. THERE
WERE LIGHT RAIN SHOWERS REPORTED ACROSS THE BLUE MOUNTAIN FOOTHILLS
AND THE LOWER COLUMBIA BASIN...BUT PRECIPITATION AMOUNTS WERE MAINLY
JUST TRACE AMOUNTS. THE UPPER TROUGH ASSOCIATED WITH THIS SYSTEM IS
NOW LOCATED OVER THE CWA AND IT WILL SLOWLY LIFT OUT TO THE
NORTHEAST TONIGHT. ON SATURDAY ANOTHER WEATHER DISTURBANCE WILL MOVE
INTO THE REGION BRINGING ANOTHER CHANCE OF LIGHT RAIN SHOWERS...
MAINLY TO THE MOUNTAINS...HOWEVER CANNOT RULE OUT A LIGHT SPRINKLE
ELSEWHERE. AGAIN PRECIPITATION AMOUNTS WILL BE VERY LIGHT. THE UPPER
TROUGH WITH THIS NEXT SYSTEM WILL MOVE ACROSS THE CWA LATE SATURDAY
AFTERNOON AND EVENING. BEHIND IT AN UPPER RIDGE WILL BEGIN TO BUILD
INTO THE REGION WITH A DRIER NORTHWEST FLOW ALOFT BEGINNING BY LATE
SUNDAY. THIS UPPER RIDGE WILL PERSIST THROUGH MONDAY EVENING. EXPECT
WARMER TEMPERATURES ON MONDAY AS A RESULT WITH MAXIMUM TEMPERATURE
READINGS CLIMBING BACK INTO THE MID 70S IN THE LOWER ELEVATIONS AND
MID 50S TO MID 60S IN THE MOUNTAINS. THIS WILL BE SLIGHTLY ABOVE
NORMAL. A LARGE UPPER TROUGH WILL THEN SWING DOWN FROM THE GULF OF
ALASKA GOING INTO THE EXTENDED PERIOD WITH COOLER CONDITIONS AND
MORE CHANCES OF PRECIPITATION. 88
LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A RIDGE OF HIGH
PRESSURE SHOULD BRING A WARMER AND MAINLY DRY DAY FOR MONDAY. A
DISTURBANCE WILL APPROACH THE TWO STATE AREA MONDAY NIGHT THAT COULD
SPREAD SOME SHOWERS ALONG THE WA/OR CASCADES. AS A STRONG LOW
PRESSURE SYSTEM DIPS TOWARD THE PACNW TUESDAY...THE SHOWERS SHOULD
MOVE INTO THE REMAINDER OF THE REGION. THE LOW PRESSURE REMAINS
NEARLY STATIONARY AND KEEPS THE CLOUDS AND SHOWERS ALONG WITH THE
COOL TEMPERATURES ACROSS THE TWO STATE AREA THROUGH THURSDAY. THE
LOW IS FORECAST TO DRIFT NORTH AND SOME DRYING IS POSSIBLE FOR
FRIDAY AND SATURDAY ALONG WITH SLIGHTLY WARMER TEMPERATURES.
AVIATION...LCL MVFR CEILINGS WILL OCCUR ON OCCASION AT ALL TAF
SITES. A DISTURBANCE MOVING ACROSS THE REGION WILL BRING SHOWERS TO
PORTIONS OF THE REGION BEFORE SLOWLY MOVING EAST AND CONDITIONS
SHOULD RETURN TO MAINLY VFR BY 02Z. ANOTHER DISTURBANCE WILL
APPROACH THE TWO STATE AREA TOMORROW MORNING AND LOWER CEILINGS WITH
LCL MVFR CONDITIONS MAINLY NEAR TAF SITE KDLS AND KRDM AND KYKM
AFTER 15Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 42 66 40 67 / 20 20 20 10
ALW 48 68 45 67 / 20 20 20 10
PSC 48 73 45 72 / 10 20 10 10
YKM 44 68 42 70 / 10 20 10 10
HRI 46 70 45 70 / 10 20 10 10
ELN 45 66 43 66 / 10 20 10 10
RDM 37 61 30 60 / 10 30 20 10
LGD 40 62 40 60 / 30 20 20 20
GCD 41 59 36 61 / 20 30 20 10
DLS 48 65 45 65 / 10 20 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SATURDAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
89/97/89
000
FXUS66 KPDT 172123
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
220 PM PDT FRI MAY 17 2013
.SHORT TERM...TONIGHT THROUGH MONDAY...A WEATHER DISTURBANCE
CONTINUES TO MOVE ACROSS THE FORECAST AREA THIS AFTERNOON. THERE
WERE LIGHT RAIN SHOWERS REPORTED ACROSS THE BLUE MOUNTAIN FOOTHILLS
AND THE LOWER COLUMBIA BASIN...BUT PRECIPITATION AMOUNTS WERE MAINLY
JUST TRACE AMOUNTS. THE UPPER TROUGH ASSOCIATED WITH THIS SYSTEM IS
NOW LOCATED OVER THE CWA AND IT WILL SLOWLY LIFT OUT TO THE
NORTHEAST TONIGHT. ON SATURDAY ANOTHER WEATHER DISTURBANCE WILL MOVE
INTO THE REGION BRINGING ANOTHER CHANCE OF LIGHT RAIN SHOWERS...
MAINLY TO THE MOUNTAINS...HOWEVER CANNOT RULE OUT A LIGHT SPRINKLE
ELSEWHERE. AGAIN PRECIPITATION AMOUNTS WILL BE VERY LIGHT. THE UPPER
TROUGH WITH THIS NEXT SYSTEM WILL MOVE ACROSS THE CWA LATE SATURDAY
AFTERNOON AND EVENING. BEHIND IT AN UPPER RIDGE WILL BEGIN TO BUILD
INTO THE REGION WITH A DRIER NORTHWEST FLOW ALOFT BEGINNING BY LATE
SUNDAY. THIS UPPER RIDGE WILL PERSIST THROUGH MONDAY EVENING. EXPECT
WARMER TEMPERATURES ON MONDAY AS A RESULT WITH MAXIMUM TEMPERATURE
READINGS CLIMBING BACK INTO THE MID 70S IN THE LOWER ELEVATIONS AND
MID 50S TO MID 60S IN THE MOUNTAINS. THIS WILL BE SLIGHTLY ABOVE
NORMAL. A LARGE UPPER TROUGH WILL THEN SWING DOWN FROM THE GULF OF
ALASKA GOING INTO THE EXTENDED PERIOD WITH COOLER CONDITIONS AND
MORE CHANCES OF PRECIPITATION. 88
.LONG TERM...MONDAY NIGHT THROUGH SATURDAY...A RIDGE OF HIGH
PRESSURE SHOULD BRING A WARMER AND MAINLY DRY DAY FOR MONDAY. A
DISTURBANCE WILL APPROACH THE TWO STATE AREA MONDAY NIGHT THAT COULD
SPREAD SOME SHOWERS ALONG THE WA/OR CASCADES. AS A STRONG LOW
PRESSURE SYSTEM DIPS TOWARD THE PACNW TUESDAY...THE SHOWERS SHOULD
MOVE INTO THE REMAINDER OF THE REGION. THE LOW PRESSURE REMAINS
NEARLY STATIONARY AND KEEPS THE CLOUDS AND SHOWERS ALONG WITH THE
COOL TEMPERATURES ACROSS THE TWO STATE AREA THROUGH THURSDAY. THE
LOW IS FORECAST TO DRIFT NORTH AND SOME DRYING IS POSSIBLE FOR
FRIDAY AND SATURDAY ALONG WITH SLIGHTLY WARMER TEMPERATURES.
&&
.AVIATION...LCL MVFR CEILINGS WILL OCCUR ON OCCASION AT ALL TAF
SITES. A DISTURBANCE MOVING ACROSS THE REGION WILL BRING SHOWERS TO
PORTIONS OF THE REGION BEFORE SLOWLY MOVING EAST AND CONDITIONS
SHOULD RETURN TO MAINLY VFR BY 02Z. ANOTHER DISTURBANCE WILL
APPROACH THE TWO STATE AREA TOMORROW MORNING AND LOWER CEILINGS WITH
LCL MVFR CONDITIONS MAINLY NEAR TAF SITE KDLS AND KRDM AND KYKM
AFTER 15Z.
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 42 66 40 67 / 20 20 20 10
ALW 48 68 45 67 / 20 20 20 10
PSC 48 73 45 72 / 10 20 10 10
YKM 44 68 42 70 / 10 20 10 10
HRI 46 70 45 70 / 10 20 10 10
ELN 45 66 43 66 / 10 20 10 10
RDM 37 61 30 60 / 10 30 20 10
LGD 40 62 40 60 / 40 20 20 20
GCD 41 59 36 61 / 30 30 20 10
DLS 48 65 45 65 / 10 20 20 10
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
SATURDAY : GREEN
SUNDAY : GREEN
MONDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
88/97/97
000
FXUS66 KPDT 171748 AAA
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
1040 AM PDT FRI MAY 17 2013
UPDATED THE AVIATION DISCUSSION
.UPDATE...A WEAK WEATHER DISTURBANCE IS MOVING UP AND ACROSS THE
FORECAST AREA THIS MORNING. CURRENT RADAR IMAGERY IS SHOWING SOME
ASSOCIATED SHOWERS WITH THIS DISTURBANCE STRETCHING IN A LINE FROM
YAKIMA COUNTY SOUTHEAST ACROSS THE SOUTHERN PORTION OF THE LOWER
COLUMBIA BASIN INTO THE SOUTHERN BLUE MOUNTAINS/FOOTHILLS. THIS AREA
OF PRECIPITATION IS MOVING TO THE NORTH AND IT SHOULD BEGIN TO
AFFECT THE NORTHERN BLUE MOUNTAIN FOOTHILLS AND THE NORTHERN AREAS
OF THE LOWER COLUMBIA BASIN...THE SIMCOE HIGHLANDS AND THE NORTHERN
BLUE MOUNTAINS WITHIN THE NEXT COUPLE OF HOURS. PRECIPITATION
AMOUNTS WILL BE VERY LIGHT AND MOST OF IT MAY NOT EVEN REACH THE
GROUND EXCEPT FOR THE HIGHER ELEVATIONS WHERE THERE IS LESS CHANCE
FOR EVAPORATION AS THE PRECIP FALLS. THERE SHOULD BE PARTIAL
CLEARING THIS AFTERNOON. THIS WILL ALLOW SURFACE HEATING TO TAKE
PLACE WHICH WILL HELP TO DESTABILIZE THE ATMOSPHERE. HAVE ISOLATED
THUNDERSTORMS IN FOR THIS AFTERNOON OVER THE EASTERN AND SOUTHEAST
ZONES STRETCHING FROM THE JOHN DAY HIGHLANDS NORTHEAST ACROSS THE
BLUE MOUNTAINS EASTWARD TO THE IDAHO BORDER. ANY THUNDERSTORMS THAT
DEVELOP SHOULD BE WEAK AND NON-SEVERE. HOWEVER THERE COULD BE GUSTY
AND ERRATIC WINDS...BRIEF HEAVY RAIN AND SMALL HAIL WITH ANY STORMS
THAT FORM. 88
.AVIATION...LCL MVFR CEILINGS WILL OCCUR ON OCCASION AT ALL TAF
SITES. A DISTURBANCE MOVING ACROSS THE REGION WILL BRING SHOWERS TO
PORTIONS OF THE REGION BEFORE SLOWLY MOVING EAST AND CONDITIONS
SHOULD RETURN TO MAINLY VFR BY 02Z. ANOTHER DISTURBANCE WILL
APPROACH THE TWO STATE AREA TOMORROW MORNING AND LOWER CEILINGS WITH
LCL MVFR CONDITIONS MAINLY NEAR TAF SITE KDLS AND KRDM AND KYKM
AFTER 15Z.
&&
.PREV DISCUSSION... /ISSUED 421 AM PDT FRI MAY 17 2013/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A BROAD UPPER LEVEL
TROUGH WILL LINGER OVER EASTERN WASHINGTON AND OREGON TODAY THROUGH
SATURDAY MORNING. THE TROUGH WILL SHIFT EAST SATURDAY AFTERNOON. THE
TROUGH WILL KEEP CLOUDS AND VARYING CHANCES OF SHOWERS OVER THE AREA
TODAY THROUGH SATURDAY EVENING. DAYTIME HEATING WILL ENHANCE THE
INSTABILITY ASSOCIATED WITH THE TROUGH THIS AFTERNOON...ESPECIALLY
OVER GRANT COUNTY TO THE BLUES AND WALLOWA COUNTY. THIS MAY TRIGGER
A FEW THUNDERSTORMS DURING THE AFTERNOON AND EVENING IN THESE AREAS.
THERE WILL BE A BRIEF BREAK LATE TONIGHT AS THE ATMOSPHERE BRIEFLY
STABILIZES WITH THE LOSS OF DAYTIME HEATING. AS THE TROUGH SHIFTS
EAST SATURDAY EVENING SHOWERS WILL END. SHOWERS WILL LINGER
OVERNIGHT IN WALLOWA COUNTY. WINDS WILL INCREASE SATURDAY AFTERNOON
AND EVENING BEHIND THE TROUGH...PARTICULARLY THROUGH THE COLUMBIA
RIVER GORGE AND KITTITAS VALLEY WHERE GAPS IN THE CASCADES FUNNEL
THE WINDS. COONFIELD
LONG TERM...SUNDAY THROUGH MONDAY NIGHT...A MID/UPPER LEVEL TROUGH
WILL EXIT THE FORECAST AREA SUNDAY FOR A DRYING TREND KICKING IN FOR
MOST OF THE FORECAST AREA. HOWEVER, SOME WRAP AROUND MOISTURE WILL
KEEP A SLIGHT CHANCE OF SHOWERS OVER THE BLUE MOUNTAINS AND FAR
NORTHEAST OREGON THROUGH SUNDAY AFTERNOON. SUNDAY NIGHT A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/137W IN THE SOUTHERN JETSTREAM. MONDAY THESE TWO SYSTEMS
BEGIN MERGING WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD
INTO THE EASTERN FLANK OF THE MID/UPPER LEVEL CIRCULATION ASSOCIATED
WITH THE UPPER LOW MOVING SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
TUESDAY THROUGH THURSDAY...ON TUESDAY THE LARGE UPPER LOW CONTINUES
MOVING SOUTHEAST WITH THE CENTER OF THE LOW ARRIVING ON THE COAST
JUST NORTH OF THE COLUMBIA RIVER BY TUESDAY AFTERNOON. THIS WILL
CAUSE A SOUTHWEST FLOW ALOFT TO BACK TO THE SOUTH OVER THE INTERIOR
PACIFIC NORTHWEST AND TRANSPORT MOISTURE AND INCREASING INSTABILITY
INTO THE REGION. THE APPROACHING COLD UPPER LOW WILL USHER IN A
COOLING TREND, AS THE UPPER LOW CENTER COMES NEARER TO THE FORECAST
AREA. THE UPPER LOW WILL PERSIST OVER THE PACIFIC NORTHWEST THROUGH
THURSDAY. HOWEVER, FROM ONE RUN TO THE NEXT, THE GFS AND ECMWF
SOLUTIONS ARE EXHIBITING SIGNIFICANT DIFFERENCES IN THE PLACEMENT OF
THE CENTER OF THE UPPER LOW, AND A COMPARISON OF THE PLACEMENT OF
THE CENTER OF THE UPPER LOW BETWEEN THE GFS AND ECMWF MODELS FOR A
GIVEN FORECAST BASE TIME LIKEWISE SHOW SIGNIFICANT DIFFERENCES. AS
SUCH UNCERTAINTY IN THE FORECAST IS GREATER THAN NORMAL FOR TUESDAY
THROUGH THURSDAY IN TERMS OF LARGE STANDARD DEVIATIONS IN THE
OVERALL 500MB HEIGHT PATTERN IN BOTH MODELS. HOWEVER, WITH EACH
ADDITIONAL MODEL RUN, THE GFS AND ECMWF MODELS ARE DISPLAYING BETTER
AGREEMENT FOR TUESDAY THROUGH THURSDAY. EXPECT COOL AND UNSETTLED
CONDITIONS WITH PERIODS OF SHOWERS EACH DAY FROM TUESDAY THROUGH
THURSDAY. DAYTIME HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN
NORMAL. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 69 45 68 43 / 20 20 20 20
ALW 70 51 70 48 / 20 20 20 20
PSC 76 51 75 48 / 10 10 10 10
YKM 72 47 70 45 / 20 10 10 10
HRI 73 49 72 48 / 10 10 20 10
ELN 72 48 68 46 / 20 10 20 10
RDM 63 40 63 33 / 20 10 30 20
LGD 63 43 64 43 / 40 40 20 20
GCD 63 44 61 39 / 50 30 20 20
DLS 70 51 67 48 / 20 10 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SATURDAY : GREEN
SUNDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
88/99/99
000
FXUS66 KPDT 171520
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
820 AM PDT FRI MAY 17 2013
.UPDATE...A WEAK WEATHER DISTURBANCE IS MOVING UP AND ACROSS THE
FORECAST AREA THIS MORNING. CURRENT RADAR IMAGERY IS SHOWING SOME
ASSOCIATED SHOWERS WITH THIS DISTURBANCE STRETCHING IN A LINE FROM
YAKIMA COUNTY SOUTHEAST ACROSS THE SOUTHERN PORTION OF THE LOWER
COLUMBIA BASIN INTO THE SOUTHERN BLUE MOUNTAINS/FOOTHILLS. THIS AREA
OF PRECIPITATION IS MOVING TO THE NORTH AND IT SHOULD BEGIN TO
AFFECT THE NORTHERN BLUE MOUNTAIN FOOTHILLS AND THE NORTHERN AREAS
OF THE LOWER COLUMBIA BASIN...THE SIMCOE HIGHLANDS AND THE NORTHERN
BLUE MOUNTAINS WITHIN THE NEXT COUPLE OF HOURS. PRECIPITATION
AMOUNTS WILL BE VERY LIGHT AND MOST OF IT MAY NOT EVEN REACH THE
GROUND EXCEPT FOR THE HIGHER ELEVATIONS WHERE THERE IS LESS CHANCE
FOR EVAPORATION AS THE PRECIP FALLS. THERE SHOULD BE PARTIAL
CLEARING THIS AFTERNOON. THIS WILL ALLOW SURFACE HEATING TO TAKE
PLACE WHICH WILL HELP TO DESTABILIZE THE ATMOSPHERE. HAVE ISOLATED
THUNDERSTORMS IN FOR THIS AFTERNOON OVER THE EASTERN AND SOUTHEAST
ZONES STRETCHING FROM THE JOHN DAY HIGHLANDS NORTHEAST ACROSS THE
BLUE MOUNTAINS EASTWARD TO THE IDAHO BORDER. ANY THUNDERSTORMS THAT
DEVELOP SHOULD BE WEAK AND NON-SEVERE. HOWEVER THERE COULD BE GUSTY
AND ERRATIC WINDS...BRIEF HEAVY RAIN AND SMALL HAIL WITH ANY STORMS
THAT FORM. 88
&&
.PREV DISCUSSION... /ISSUED 421 AM PDT FRI MAY 17 2013/
SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A BROAD UPPER LEVEL
TROUGH WILL LINGER OVER EASTERN WASHINGTON AND OREGON TODAY THROUGH
SATURDAY MORNING. THE TROUGH WILL SHIFT EAST SATURDAY AFTERNOON. THE
TROUGH WILL KEEP CLOUDS AND VARYING CHANCES OF SHOWERS OVER THE AREA
TODAY THROUGH SATURDAY EVENING. DAYTIME HEATING WILL ENHANCE THE
INSTABILITY ASSOCIATED WITH THE TROUGH THIS AFTERNOON...ESPECIALLY
OVER GRANT COUNTY TO THE BLUES AND WALLOWA COUNTY. THIS MAY TRIGGER
A FEW THUNDERSTORMS DURING THE AFTERNOON AND EVENING IN THESE AREAS.
THERE WILL BE A BRIEF BREAK LATE TONIGHT AS THE ATMOSPHERE BRIEFLY
STABILIZES WITH THE LOSS OF DAYTIME HEATING. AS THE TROUGH SHIFTS
EAST SATURDAY EVENING SHOWERS WILL END. SHOWERS WILL LINGER
OVERNIGHT IN WALLOWA COUNTY. WINDS WILL INCREASE SATURDAY AFTERNOON
AND EVENING BEHIND THE TROUGH...PARTICULARLY THROUGH THE COLUMBIA
RIVER GORGE AND KITTITAS VALLEY WHERE GAPS IN THE CASCADES FUNNEL
THE WINDS. COONFIELD
LONG TERM...SUNDAY THROUGH MONDAY NIGHT...A MID/UPPER LEVEL TROUGH
WILL EXIT THE FORECAST AREA SUNDAY FOR A DRYING TREND KICKING IN FOR
MOST OF THE FORECAST AREA. HOWEVER, SOME WRAP AROUND MOISTURE WILL
KEEP A SLIGHT CHANCE OF SHOWERS OVER THE BLUE MOUNTAINS AND FAR
NORTHEAST OREGON THROUGH SUNDAY AFTERNOON. SUNDAY NIGHT A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/137W IN THE SOUTHERN JETSTREAM. MONDAY THESE TWO SYSTEMS
BEGIN MERGING WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD
INTO THE EASTERN FLANK OF THE MID/UPPER LEVEL CIRCULATION ASSOCIATED
WITH THE UPPER LOW MOVING SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
TUESDAY THROUGH THURSDAY...ON TUESDAY THE LARGE UPPER LOW CONTINUES
MOVING SOUTHEAST WITH THE CENTER OF THE LOW ARRIVING ON THE COAST
JUST NORTH OF THE COLUMBIA RIVER BY TUESDAY AFTERNOON. THIS WILL
CAUSE A SOUTHWEST FLOW ALOFT TO BACK TO THE SOUTH OVER THE INTERIOR
PACIFIC NORTHWEST AND TRANSPORT MOISTURE AND INCREASING INSTABILITY
INTO THE REGION. THE APPROACHING COLD UPPER LOW WILL USHER IN A
COOLING TREND, AS THE UPPER LOW CENTER COMES NEARER TO THE FORECAST
AREA. THE UPPER LOW WILL PERSIST OVER THE PACIFIC NORTHWEST THROUGH
THURSDAY. HOWEVER, FROM ONE RUN TO THE NEXT, THE GFS AND ECMWF
SOLUTIONS ARE EXHIBITING SIGNIFICANT DIFFERENCES IN THE PLACEMENT OF
THE CENTER OF THE UPPER LOW, AND A COMPARISON OF THE PLACEMENT OF
THE CENTER OF THE UPPER LOW BETWEEN THE GFS AND ECMWF MODELS FOR A
GIVEN FORECAST BASE TIME LIKEWISE SHOW SIGNIFICANT DIFFERENCES. AS
SUCH UNCERTAINTY IN THE FORECAST IS GREATER THAN NORMAL FOR TUESDAY
THROUGH THURSDAY IN TERMS OF LARGE STANDARD DEVIATIONS IN THE
OVERALL 500MB HEIGHT PATTERN IN BOTH MODELS. HOWEVER, WITH EACH
ADDITIONAL MODEL RUN, THE GFS AND ECMWF MODELS ARE DISPLAYING BETTER
AGREEMENT FOR TUESDAY THROUGH THURSDAY. EXPECT COOL AND UNSETTLED
CONDITIONS WITH PERIODS OF SHOWERS EACH DAY FROM TUESDAY THROUGH
THURSDAY. DAYTIME HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN
NORMAL. POLAN
AVIATION...12Z TAFS...VFR CONDITIONS WILL OCCUR OVER THE NEXT 24
HOURS, EXCEPT AT KBDN WHERE MVFR CIGS ARE LIKELY THIS MORNING.
HOWEVER, SOME TAF SITES MAY EXPERIENCE BRIEF MVFR CONDITIONS DUE TO
LOWERED CIGS FROM SHOWERS. AN APPROACHING MID/UPPER LEVEL TROUGH
JUST WEST OF THE CASCADES AT 4 AM THIS MORNING IS STEERING SHOWERS
ALONG A TRACK DUE NORTHWARD FROM THE EASTERN COLUMBIA RIVER GORGE
SOUTH ACROSS NORTH CENTRAL OREGON AND TO THE SOUTHEAST OVER THE JOHN
DAY RIVER VALLEY. SHOWERS WILL INCREASE IN AREAL COVERAGE AS THE
TROUGH OVERSPREADS CENTRAL AND NE OREGON LATE THIS MORNING THROUGH
THIS EVENING. SHOWERS WILL THEN TAPER OFF AFTER 03Z/18TH. WINDS WILL
BE BREEZY AFTER 21Z AT JUST ABOUT ALL TAF SITES OTHER THAN KPSC AND
KYKM. EXPECT WINDS 5 TO 15 KTS WITH GUSTS OF 20 TO 25 KTS. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 69 45 68 43 / 20 20 20 20
ALW 70 51 70 48 / 20 20 20 20
PSC 76 51 75 48 / 10 10 10 10
YKM 72 47 70 45 / 20 10 10 10
HRI 73 49 72 48 / 10 10 20 10
ELN 72 48 68 46 / 20 10 20 10
RDM 63 40 63 33 / 20 10 30 20
LGD 63 43 64 43 / 40 40 20 20
GCD 63 44 61 39 / 50 30 20 20
DLS 70 51 67 48 / 20 10 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SATURDAY : GREEN
SUNDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
88/99/99
000
FXUS66 KPDT 171122 AAA
AFDPDT
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE PENDLETON OR
421 AM PDT FRI MAY 17 2013
UPDATED AVIATION AND LONG TERM DISCUSSIONS
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A BROAD UPPER LEVEL
TROUGH WILL LINGER OVER EASTERN WASHINGTON AND OREGON TODAY THROUGH
SATURDAY MORNING. THE TROUGH WILL SHIFT EAST SATURDAY AFTERNOON. THE
TROUGH WILL KEEP CLOUDS AND VARYING CHANCES OF SHOWERS OVER THE AREA
TODAY THROUGH SATURDAY EVENING. DAYTIME HEATING WILL ENHANCE THE
INSTABILITY ASSOCIATED WITH THE TROUGH THIS AFTERNOON...ESPECIALLY
OVER GRANT COUNTY TO THE BLUES AND WALLOWA COUNTY. THIS MAY TRIGGER
A FEW THUNDERSTORMS DURING THE AFTERNOON AND EVENING IN THESE AREAS.
THERE WILL BE A BRIEF BREAK LATE TONIGHT AS THE ATMOSPHERE BRIEFLY
STABILIZES WITH THE LOSS OF DAYTIME HEATING. AS THE TROUGH SHIFTS
EAST SATURDAY EVENING SHOWERS WILL END. SHOWERS WILL LINGER
OVERNIGHT IN WALLOWA COUNTY. WINDS WILL INCREASE SATURDAY AFTERNOON
AND EVENING BEHIND THE TROUGH...PARTICULARLY THROUGH THE COLUMBIA
RIVER GORGE AND KITTITAS VALLEY WHERE GAPS IN THE CASCADES FUNNEL
THE WINDS. COONFIELD
.LONG TERM...SUNDAY THROUGH MONDAY NIGHT...A MID/UPPER LEVEL TROUGH
WILL EXIT THE FORECAST AREA SUNDAY FOR A DRYING TREND KICKING IN FOR
MOST OF THE FORECAST AREA. HOWEVER, SOME WRAP AROUND MOISTURE WILL
KEEP A SLIGHT CHANCE OF SHOWERS OVER THE BLUE MOUNTAINS AND FAR
NORTHEAST OREGON THROUGH SUNDAY AFTERNOON. SUNDAY NIGHT A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/137W IN THE SOUTHERN JETSTREAM. MONDAY THESE TWO SYSTEMS
BEGIN MERGING WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD
INTO THE EASTERN FLANK OF THE MID/UPPER LEVEL CIRCULATION ASSOCIATED
WITH THE UPPER LOW MOVING SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
TUESDAY THROUGH THURSDAY...ON TUESDAY THE LARGE UPPER LOW CONTINUES
MOVING SOUTHEAST WITH THE CENTER OF THE LOW ARRIVING ON THE COAST
JUST NORTH OF THE COLUMBIA RIVER BY TUESDAY AFTERNOON. THIS WILL
CAUSE A SOUTHWEST FLOW ALOFT TO BACK TO THE SOUTH OVER THE INTERIOR
PACIFIC NORTHWEST AND TRANSPORT MOISTURE AND INCREASING INSTABILITY
INTO THE REGION. THE APPROACHING COLD UPPER LOW WILL USHER IN A
COOLING TREND, AS THE UPPER LOW CENTER COMES NEARER TO THE FORECAST
AREA. THE UPPER LOW WILL PERSIST OVER THE PACIFIC NORTHWEST THROUGH
THURSDAY. HOWEVER, FROM ONE RUN TO THE NEXT, THE GFS AND ECMWF
SOLUTIONS ARE EXHIBITING SIGNIFICANT DIFFERENCES IN THE PLACEMENT OF
THE CENTER OF THE UPPER LOW, AND A COMPARISON OF THE PLACEMENT OF
THE CENTER OF THE UPPER LOW BETWEEN THE GFS AND ECMWF MODELS FOR A
GIVEN FORECAST BASE TIME LIKEWISE SHOW SIGNIFICANT DIFFERENCES. AS
SUCH UNCERTAINTY IN THE FORECAST IS GREATER THAN NORMAL FOR TUESDAY
THROUGH THURSDAY IN TERMS OF LARGE STANDARD DEVIATIONS IN THE
OVERALL 500MB HEIGHT PATTERN IN BOTH MODELS. HOWEVER, WITH EACH
ADDITIONAL MODEL RUN, THE GFS AND ECMWF MODELS ARE DISPLAYING BETTER
AGREEMENT FOR TUESDAY THROUGH THURSDAY. EXPECT COOL AND UNSETTLED
CONDITIONS WITH PERIODS OF SHOWERS EACH DAY FROM TUESDAY THROUGH
THURSDAY. DAYTIME HIGH TEMPERATURES WILL BE SLIGHTLY COOLER THAN
NORMAL. POLAN
&&
.AVIATION...12Z TAFS...VFR CONDITIONS WILL OCCUR OVER THE NEXT 24
HOURS, EXCEPT AT KBDN WHERE MVFR CIGS ARE LIKELY THIS MORNING.
HOWEVER, SOME TAF SITES MAY EXPERIENCE BRIEF MVFR CONDITIONS DUE TO
LOWERED CIGS FROM SHOWERS. AN APPROACHING MID/UPPER LEVEL TROUGH
JUST WEST OF THE CASCADES AT 4 AM THIS MORNING IS STEERING SHOWERS
ALONG A TRACK DUE NORTHWARD FROM THE EASTERN COLUMBIA RIVER GORGE
SOUTH ACROSS NORTH CENTRAL OREGON AND TO THE SOUTHEAST OVER THE JOHN
DAY RIVER VALLEY. SHOWERS WILL INCREASE IN AREAL COVERAGE AS THE
TROUGH OVERSPREADS CENTRAL AND NE OREGON LATE THIS MORNING THROUGH
THIS EVENING. SHOWERS WILL THEN TAPER OFF AFTER 03Z/18TH. WINDS WILL
BE BREEZY AFTER 21Z AT JUST ABOUT ALL TAF SITES OTHER THAN KPSC AND
KYKM. EXPECT WINDS 5 TO 15 KTS WITH GUSTS OF 20 TO 25 KTS. POLAN
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 69 45 68 43 / 20 20 20 20
ALW 70 51 70 48 / 20 20 20 20
PSC 76 51 75 48 / 10 10 10 10
YKM 72 47 70 45 / 20 10 10 10
HRI 73 49 72 48 / 10 10 20 10
ELN 72 48 68 46 / 20 10 20 10
RDM 63 40 63 33 / 20 10 30 20
LGD 63 43 64 43 / 40 40 20 20
GCD 63 44 61 39 / 50 30 20 20
DLS 70 51 67 48 / 20 10 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SATURDAY : GREEN
SUNDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
000
FXUS66 KPDT 171005
AFDPDT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PENDLETON OR
304 AM PDT FRI MAY 17 2013
.SHORT TERM...TODAY THROUGH SATURDAY NIGHT...A BROAD UPPER LEVEL
TROUGH WILL LINGER OVER EASTERN WASHINGTON AND OREGON TODAY THROUGH
SATURDAY MORNING. THE TROUGH WILL SHIFT EAST SATURDAY AFTERNOON. THE
TROUGH WILL KEEP CLOUDS AND VARYING CHANCES OF SHOWERS OVER THE AREA
TODAY THROUGH SATURDAY EVENING. DAYTIME HEATING WILL ENHANCE THE
INSTABILITY ASSOCIATED WITH THE TROUGH THIS AFTERNOON...ESPECIALLY
OVER GRANT COUNTY TO THE BLUES AND WALLOWA COUNTY. THIS MAY TRIGGER
A FEW THUNDERSTORMS DURING THE AFTERNOON AND EVENING IN THESE AREAS.
THERE WILL BE A BRIEF BREAK LATE TONIGHT AS THE ATMOSPHERE BRIEFLY
STABILIZES WITH THE LOSS OF DAYTIME HEATING. AS THE TROUGH SHIFTS
EAST SATURDAY EVENING SHOWERS WILL END. SHOWERS WILL LINGER
OVERNIGHT IN WALLOWA COUNTY. WINDS WILL INCREASE SATURDAY AFTERNOON
AND EVENING BEHIND THE TROUGH...PARTICULARLY THROUGH THE COLUMBIA
RIVER GORGE AND KITTITAS VALLEY WHERE GAPS IN THE CASCADES FUNNEL
THE WINDS. COONFIELD
.LONG TERM...SUNDAY THROUGH MONDAY NIGHT...A MID/UPPER LEVEL TROUGH
WILL EXIT THE FORECAST AREA SUNDAY FOR A DRYING TREND KICKING IN FOR
MOST OF THE FORECAST AREA. HOWEVER, SOME WRAP AROUND MOISTURE WILL
KEEP A SLIGHT CHANCE OF SHOWERS OVER THE BLUE MOUNTAINS AND FAR
NORTHEAST OREGON THROUGH SUNDAY AFTERNOON. SUNDAY NIGHT A LARGE
UPPER LEVEL LOW PRESSURE SYSTEM MOVES SOUTHEAST ALONG THE SE ALASKAN
ARCHIPELAGO AND COMES INTO PHASE WITH A FRONTAL ZONE MOVING EAST
NEAR 45N/137W IN THE SOUTHERN JETSTREAM. MONDAY THESE TWO SYSTEMS
BEGIN MERGING WITH THE SOUTHERN SYSTEM PULLING MOISTURE NORTHWARD
INTO THE EASTERN FLANK OF THE MID/UPPER LEVEL CIRCULATION ASSOCIATED
WITH THE UPPER LOW MOVING SOUTHEAST NEAR QUEEN CHARLOTTE ISLAND.
.TUESDAY THROUGH THURSDAY...ON TUESDAY THE UPPER LOW CONTINUES
MOVING SOUTHEAST WITH THE LOW ARRIVING ON THE COAST BY TUESDAY
AFTERNOON. THIS WILL CAUSE A SOUTHWEST FLOW TO BACK TO THE SOUTH
OVER THE INTERIOR PACIFIC NORTHWEST AND TRANSPORT MOISTURE AND
INCREASING INSTABILITY INTO THE REGION. THE APPROACHING COLD UPPER
LOW MEANS A COOLING TREND WILL TAKE PLACE WITH FALLING HEIGHTS AND
THICKNESSES, AS THE UPPER LOW CENTER COMES MUCH CLOSER TO THE AREA.
THIS PATTERN OF UPPER LOWS WILL PERSIST THROUGHOUT THE REMAINDER OF
THE EXTENDED FORECAST PERIOD... THOUGH WITH VERY SIGNIFICANT
DIFFERENCES IN THE PLACEMENT OF THE UPPER LOWS BETWEEN THESE TWO
MODELS. AS SUCH DID NOT MAKE TOO MANY CHANGES IN THE EXTENDED
FORECAST PERIOD DUE TO THE UNCERTAINTY. HOWEVER THERE IS BETTER
AGREEMENT BETWEEN THE TWO MODELS BY THURSDAY AND THEN THE MODELS
DIVERGE AGAIN FURTHER OUT IN THE EXTENDED FORECAST PERIOD WITH THE
ECMWF BEING MUCH MORE ORGANIZED AND DEEPER THAN THE GFS AND AM
LEANING TOWARD THAT SCENARIO. THE RESULT WILL BE COOL CONDITIONS
WITH PERIODIC SHOWERS. EVEN THOUGH TEMPERATURES WILL BE ON THE COOL
SIDE THEY WILL NOT BE MUCH COOLER THAN NORMAL AND IN FACT THEY WILL
BE CLOSE TO NORMAL FOR THIS TIME OF YEAR. POLAN
&&
.PREVIOUS AVIATION DISCUSSION...06Z TAFS...VFR CONDITIONS ARE
EXPECTED TO PREVAIL OVER THE NEXT 24 HOURS. HOWEVER...SOME TAF SITES
MAY EXPERIENCE BRIEF MVFR CONDITIONS DUE TO LOWERED CIGS FROM
SHOWERS. SHOWERS WILL TAPER OFF OVERNIGHT TONIGHT AND PICK BACK UP
TOMORROW LATE MORNING TO EARLY AFTERNOON. WINDS WILL BE BREEZY AFTER
21Z AT JUST ABOUT ALL TAF SITES OTHER THAN KPSC AND KYKM. EXPECT
WINDS 5 TO 15KTS WITH 20 TO 25KTS AT TIMES. WEBER
&&
.PRELIMINARY POINT TEMPS/POPS...
PDT 69 45 68 43 / 20 20 20 20
ALW 70 51 70 48 / 20 20 20 20
PSC 76 51 75 48 / 10 10 10 10
YKM 72 47 70 45 / 20 10 10 10
HRI 73 49 72 48 / 10 10 20 10
ELN 72 48 68 46 / 20 10 20 10
RDM 63 40 63 33 / 20 10 30 20
LGD 63 43 64 43 / 40 40 20 20
GCD 63 44 61 39 / 50 30 20 20
DLS 70 51 67 48 / 20 10 20 20
&&
.PDT WATCHES/WARNINGS/ADVISORIES...
OR...NONE.
WA...NONE.
&&
THREAT INDEX
TODAY : GREEN
SATURDAY : GREEN
SUNDAY : GREEN
GREEN: NONE OR LIMITED NEED FOR WATCHES, WARNINGS, OR ADVISORIES.
YELLOW: A FEW WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
RED: NUMEROUS WATCHES, WARNINGS, OR ADVISORIES POSSIBLE OR IN EFFECT.
FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT...
WWW.WEATHER.GOV/PENDLETON
$$
76/99/99
|
