Winter Storm Warning 21, NWS Seattle, WA

000 
WWUS46 KSEW 311157
WSWSEW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE SEATTLE WA
457 AM PDT TUE MAR 31 2009

WAZ518-519-312300-
/O.CON.KSEW.WS.W.0021.000000T0000Z-090401T0700Z/
WEST SLOPES NORTHERN CASCADES AND PASSES-
WEST SLOPES CENTRAL CASCADES AND PASSES-
457 AM PDT TUE MAR 31 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PDT
TONIGHT...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PDT
TONIGHT FOR THE CENTRAL AND NORTHERN CASCADES. 

SNOW WILL CONTINUE THIS MORNING AS A WEATHER SYSTEM PASSES ACROSS
THE REGION. THE ASSOCIATED COLD FRONT WILL PASS THROUGH WESTERN
WASHINGTON THIS MORNING...WITH SHOWERS CONTINUING INTO THE
EVENING. STRONG WESTERLY FLOW ALOFT WILL ENHANCE PRECIPITATION
ACROSS THE CASCADES WITH ANOTHER ROUND OF HEAVY SNOW
EXPECTED...ESPECIALLY DURING THE AFTERNOON AND EVENING AS A PUGET
SOUND CONVERGENCE ZONE DEVELOPS.

TOTAL SNOWFALL ACCUMULATIONS WILL RANGE FROM 1 TO 2 FEET ACROSS
THE CASCADES THROUGH THIS EVENING. THE SNOW LEVEL NEAR 3000 FEET
EARLY THIS MORNING WILL DROP TO AROUND 1500 FEET BY THIS EVENING.

AN AVALANCHE WATCH IS ALSO IN EFFECT FOR THE CASCADES. FOR MORE
INFORMATION VISIT WWW.NWAC.US.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WARNING MEANS SEVERE WINTER WEATHER IS OCCURRING
OR IMMINENT. THOSE PLANNING TRAVEL IN THE WARNED AREA SHOULD BE
PREPARED FOR HAZARDOUS...WINTER DRIVING CONDITIONS AND PLAN
ACCORDINGLY.

FOR THE LATEST PASS CONDITIONS...CALL 511 OR 800-695-ROAD...OR
VISIT THE WASHINGTON STATE DEPARTMENT OF TRANSPORTATION WEB SITE
AT WWW.WSDOT.WA.GOV.

&&

$$

WAZ513-312300-
/O.CON.KSEW.WW.Y.0021.000000T0000Z-090401T0100Z/
OLYMPICS-
457 AM PDT TUE MAR 31 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM PDT THIS
EVENING...

A WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM PDT THIS
EVENING FOR THE OLYMPICS. 

SNOW WILL CONTINUE THIS MORNING AS A WEATHER SYSTEM PASSES ACROSS
THE REGION. THE ASSOCIATED COLD FRONT WILL PASS THROUGH WESTERN
WASHINGTON THIS MORNING...WITH SHOWERS CONTINUING INTO THE
EVENING.

TOTAL SNOWFALL ACCUMULATIONS WILL RANGE FROM 8 TO 16 INCHES
ACROSS THE OLYMPIC MOUNTAINS. THE HEAVIEST AMOUNTS WILL BE FOUND
ALONG THE WEST FACING SLOPES. SNOW LEVELS AROUND 3500 FEET EARLY
THIS MORNING WILL DROP TO 1500 FEET BY EVENING.

AN AVALANCHE WATCH IS ALSO IN EFFECT FOR THE OLYMPICS. FOR MORE
INFORMATION VISIT WWW.NWAC.US.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER WEATHER ADVISORY FOR SNOW MEANS THAT PERIODS OF SNOW
WILL CAUSE PRIMARILY TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW
COVERED ROADS AND LIMITED VISIBILITIES...AND USE CAUTION WHILE
DRIVING.

&&

$$

CERNIGLIA

000 
WWUS46 KSEW 312332
WSWSEW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE SEATTLE WA
432 PM PDT TUE MAR 31 2009

WAZ518-519-010700-
/O.NEW.KSEW.WS.A.0008.090401T1800Z-090403T0000Z/
/O.CON.KSEW.WS.W.0021.000000T0000Z-090401T0700Z/
WEST SLOPES NORTHERN CASCADES AND PASSES-
WEST SLOPES CENTRAL CASCADES AND PASSES-
432 PM PDT TUE MAR 31 2009

...WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PDT
TONIGHT...
...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY MORNING THROUGH
THURSDAY AFTERNOON...

A WINTER STORM WARNING REMAINS IN EFFECT UNTIL MIDNIGHT PDT
TONIGHT FOR THE NORTH AND CENTRAL CASCADES.

SNOWFALL WILL TAPER OFF LATER THIS EVENING AS THE SHOWER ACTIVITY
WINDS DOWN. ADDITIONAL ACCUMULATIONS OF 1 TO 5 INCHES ARE POSSIBLE
WITH THE HIGHEST TOTALS FOR THE CENTRAL CASCADES. 

AN AVALANCHE WARNING REMAINS IN EFFECT THROUGH LATE TONIGHT. FOR MORE
INFORMATION VISIT WWW.NWAC.US.

THE NATIONAL WEATHER SERVICE IN SEATTLE HAS ISSUED A WINTER STORM
WATCH...WHICH IS IN EFFECT FROM LATE WEDNESDAY MORNING THROUGH
THURSDAY AFTERNOON.

YET ANOTHER SPRING SNOW STORM WILL BRING HEAVY SNOW TO THE
CASCADES. SNOW WILL BEGIN LATE WEDNESDAY MORNING...AND TURN TO
SHOWERS ON THURSDAY. SNOWFALL TOTALS OF ONE TO OVER TWO FEET COULD
BE POSSIBLE BY LATE THURSDAY AFTERNOON. SNOW LEVELS WILL START OUT
LOW AROUND 1500 FEET AND RISE TO 2500 FEET WEDNESDAY NIGHT. 

STAY TUNED FOR THE LATEST FORECAST DETAILS. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS AND POSSIBLE WARNINGS OR
ADVISORIES.

FOR THE LATEST PASS CONDITIONS...CALL 511 OR 800-695-ROAD...OR
VISIT THE WASHINGTON STATE DEPARTMENT OF TRANSPORTATION WEB SITE
AT WWW.WSDOT.WA.GOV.

&&

$$

WAZ513-010700-
/O.NEW.KSEW.WS.A.0008.090401T1800Z-090403T0000Z/
/O.CON.KSEW.WW.Y.0021.000000T0000Z-090401T0100Z/
OLYMPICS-
432 PM PDT TUE MAR 31 2009

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM PDT THIS
EVENING...
...WINTER STORM WATCH IN EFFECT FROM WEDNESDAY MORNING THROUGH
THURSDAY AFTERNOON...

...WINTER WEATHER ADVISORY REMAINS IN EFFECT UNTIL 6 PM PDT THIS
EVENING FOR THE OLYMPIC MOUNTAINS...

SNOW SHOWERS WILL CONTINUE TO TAPER OFF THIS EVENING.

AN AVALANCHE WARNING REMAINS IN EFFECT THROUGH LATE TONIGHT. FOR MORE
INFORMATION VISIT WWW.NWAC.US.

THE NATIONAL WEATHER SERVICE IN SEATTLE HAS ISSUED A WINTER STORM
WATCH FOR THE OLYMPIC MOUNTAINS...WHICH IS IN EFFECT FROM WEDNESDAY MORNING
THROUGH THURSDAY AFTERNOON.

YET ANOTHER SPRING SNOW STORM WILL BRING HEAVY SNOW TO THE
CASCADES. SNOW WILL BEGIN LATE WEDNESDAY MORNING...AND TURN TO
SHOWERS ON THURSDAY. SNOWFALL TOTALS OF ONE TO TWO FEET ARE POSSIBLE
BY LATE THURSDAY AFTERNOON. SNOW LEVELS WILL START OUT LOW AROUND
2000 FEET AND RISE TO 3000 FEET WEDNESDAY NIGHT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS AND POSSIBLE WARNINGS OR
ADVISORIES.

&&

$$

000 
WWUS46 KSEW 010657
WSWSEW

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE SEATTLE WA
1157 PM PDT TUE MAR 31 2009

WAZ518-519-011500-
/O.EXP.KSEW.WS.W.0021.000000T0000Z-090401T0700Z/
/O.CON.KSEW.WS.A.0008.090401T1800Z-090403T0000Z/
WEST SLOPES NORTHERN CASCADES AND PASSES-
WEST SLOPES CENTRAL CASCADES AND PASSES-
1157 PM PDT TUE MAR 31 2009

...WINTER STORM WATCH REMAINS IN EFFECT FROM 11 AM PDT WEDNESDAY
THROUGH THURSDAY AFTERNOON...
...WINTER STORM WARNING WILL EXPIRE AT MIDNIGHT PDT TONIGHT...

THE WINTER STORM WARNING FOR THE CASCADES WILL EXPIRE AT MIDNIGHT
PDT TONIGHT. A WINTER STORM WATCH REMAINS IN EFFECT FROM 11 AM PDT
WEDNESDAY THROUGH THURSDAY AFTERNOON.

SNOW TAPERED OFF LATE TUESDAY EVENING WITH GENERALLY SCATTERED
AREAS OF LIGHT SNOW OR FLURRIES LINGERING. ADDITIONAL SIGNIFICANT
ACCUMULATIONS ARE NOT EXPECTED THROUGH THE REMAINDER OF THE NIGHT.

AN AVALANCHE WARNING REMAINS IN EFFECT THROUGH LATE TONIGHT. FOR
MORE INFORMATION VISIT WWW.NWAC.US.

A WINTER STORM WATCH IS IN EFFECT FOR THE NORTHERN AND CENTRAL
CASCADES FOR LATE WEDNESDAY MORNING THROUGH THURSDAY AFTERNOON.

YET ANOTHER SPRING SNOW STORM WILL BRING HEAVY SNOW TO THE
CASCADES. LIGHT SNOW WILL BEGIN LATE WEDNESDAY MORNING THEN BECOME
HEAVIER WEDNESDAY NIGHT...THEN TURN TO SHOWERS ON THURSDAY.
SNOWFALL TOTALS OF ONE TO NEARLY TWO FEET COULD BE POSSIBLE BY
LATE THURSDAY AFTERNOON. SNOW LEVELS WILL START OUT LOW AROUND
1000 FEET AND RISE TO 3000 FEET WEDNESDAY NIGHT.

STAY TUNED FOR THE LATEST FORECAST DETAILS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS AND POSSIBLE WARNINGS OR
ADVISORIES.

FOR THE LATEST PASS CONDITIONS...CALL 511 OR 800-695-ROAD...OR
VISIT THE WASHINGTON STATE DEPARTMENT OF TRANSPORTATION WEB SITE
AT WWW.WSDOT.WA.GOV.

&&

$$

WAZ513-011500-
/O.CON.KSEW.WS.A.0008.090401T1800Z-090403T0000Z/
OLYMPICS-
1157 PM PDT TUE MAR 31 2009

...WINTER STORM WATCH REMAINS IN EFFECT FROM 11 AM PDT WEDNESDAY
THROUGH THURSDAY AFTERNOON...

A WINTER STORM WATCH REMAINS IN EFFECT FOR THE OLYMPICS FROM 11
AM PDT WEDNESDAY THROUGH THURSDAY AFTERNOON.

AN AVALANCHE WARNING REMAINS IN EFFECT THROUGH LATE TONIGHT. FOR
MORE INFORMATION VISIT WWW.NWAC.US.

YET ANOTHER SPRING SNOW STORM WILL BRING HEAVY SNOW TO THE
CASCADES. SNOW WILL BEGIN LATE WEDNESDAY MORNING...AND TURN TO
SHOWERS ON THURSDAY. SNOWFALL TOTALS OVER A FOOT ARE POSSIBLE BY
LATE THURSDAY AFTERNOON. SNOW LEVELS WILL START OUT LOW AROUND
1000 FEET AND RISE TO 3000 FEET WEDNESDAY NIGHT.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS AND POSSIBLE WARNINGS OR
ADVISORIES.

&&

$$

WWW.WEATHER.GOV/SEATTLE
CERNIGLIA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 AM PDT MON MAR 30 2009

.SYNOPSIS...A WARM FRONT WILL BRING LIGHT RAIN TO THE REGION
TODAY...MAINLY OUTSIDE OF THE CENTRAL PUGET SOUND AREA. A COLD FRONT
WILL PASS THROUGH THIS EVENING...WITH STRONG WESTERLY FLOW ENHANCING
PRECIPITATION OVER THE MOUNTAINS. ANOTHER FRONTAL SYSTEM WILL AFFECT
THE REGION WEDNESDAY INTO EARLY THURSDAY FOR MORE WET WEATHER AND
COOL TEMPERATURES. A RIDGE OF HIGH PRESSURE IS EXPECT TO DEVELOP
ALOFT AT THE END OF THE WEEK FOR A PERIOD OF DRIER AND WARMER
WEATHER.

&&

.SHORT TERM...MADE A FEW ADJUSTMENTS TO THE FORECAST TODAY...MAINLY
TO INCREASE POPS ALONG THE COAST AND KEEP HIGHER CLOUD COVER ACROSS
THE AREA. WEAK WARM FRONT WILL PASS THROUGH THE REGION TODAY WITH
GENERALLY MILD CONDITIONS ACROSS THE AREA...HIGHS NEAR 50. AS FOR
THE PRECIP COVERAGE...QUILLAYUTE HAS BEEN REPORTING LIGHT RAIN THIS
MORNING WITH LIGHT RAIN MOVING INLAND BY THE AFTERNOON...MAINLY
NORTH AND SW INTERIORS. MODELS KEEP THE CENTRAL SOUND DRY WITH
WESTERLY DOWNSLOPE WINDS OFF THE OLYMPICS.

WILL SEE AN UPTICK IN THE WEATHER THIS EVENING AS THE COLD FRONT
MOVES IN. THERE IS A FAIRLY DECENT MOISTURE FETCH WITH THIS SYSTEM
WITH A PLUME STRETCHING BACK WEST BEYOND 150W. WINDS ALOFT WILL ALSO
INCREASE AS THE JET NOSES IN WITH ABUNDANT OROGRAPHICS ACROSS THE
MOUNTAINS...850 MB WINDS ON THE ORDER OF 40 KT. WITH SNOW LEVELS
AROUND 2500 FT WILL LIKELY SEE ANOTHER ROUND OF HEAVY SNOW ACROSS
THE CASCADES...ESPECIALLY OVERNIGHT WITH AS A PSCZ DEVELOPS. A
WINTER STORM WATCH REMAINS IN EFFECT FOR THE N AND C CASCADES AND
WILL LIKELY UPGRADE TO A WARNING WITH THE AFTERNOON PACKAGE. LESSER
AMOUNTS WILL BE FOUND ON THE OLYMPICS...AND WOULD LIKE TO SEE THE
NEW 12Z MODEL RUNS TO DECIDE IF A WARNING IS WARRANTED. HEAVY SNOW
IS LIKELY TO LINGER THROUGH TUE AFTERNOON...WITH A DRY FORECAST FOR
THE LOWLANDS.

ANOTHER PACIFIC FRONTAL SYSTEM WILL AFFECT THE REGION ON WED...WITH
RAIN DEVELOPING ALONG THE COAST IN THE MORNING AND SPREADING INLAND
DURING THE AFTERNOON. 33

.LONG TERM...PREVIOUS DISCUSSION...A BREAK IS IN SIGHT...BUT KEEP
THE FINGERS CROSSED. A PATTERN CHANGE HAS BEEN IN THE MAKING THE
LAST DAY OR TWO IN THE MODEL WORLD FOR LATE IN THE WEEK AND THAT
TREND CONTINUES THIS MORNING. THE CHANGE RELATES TO AN UPPER RIDGE
BUILDING OVER THE WESTERN THIRD OF THE US AS THE CENTRAL US TROUGH
DECAYS...EVENTUALLY REDEVELOPING OFF THE WEST COAST. AS IT LOOKS AT
THIS TIME...THIS WILL ALLOW FOR A DRY PERIOD MOST OF FRIDAY THROUGH
AT LEAST SATURDAY WITH SATURDAY TEMPERATURES PUSHING TO NORMAL
LEVELS OR A BIT ABOVE.  (NORMAL BEING MID 50S FOR THE MOST PART)
BASED ON THIS CONTINUED TREND I HAVE DRIED OUT THIS PERIOD AND
TWEAKED THE TEMPERATURES WARMER IN COORDINATION WITH NEIGHBORING
OFFICES. THERE IS STILL SOME QUESTION AS TO HOW PROGRESSIVE THIS
RIDGE WILL BE AS LONG RANGE GUIDANCE SUGGESTS THE LONG WAVE TROUGH
SHOULD SETTLE IN ALONG THE WEST COAST SO HAVE LEFT THE CHANCE FOR
RAIN IN THE FORECAST SUNDAY ONWARD.  CERNIGLIA

&&

.AVIATION...NORTHWEST FLOW ALOFT AND SOUTHERLY TO SOUTHWESTERLY FLOW
AT LOW LEVELS WILL CONTINUE OVER WESTERN WASHINGTON THROUGH TONIGHT.
A WARM FRONT MOVING INTO BRITISH COLUMBIA WILL BRUSH WESTERN
WASHINGTON TODAY FOLLOWED BY A COLD FRONT DIGGING INTO THE AREA FROM
THE NORTHWEST LATE TONIGHT.

ABUNDANT MOISTURE SNEAKING INTO THE REGION IS HELPING TO BUMP
CEILINGS DOWN TO MVFR CRITERIA AT MANY LOCATIONS THROUGHOUT WESTERN
WASHINGTON THIS MORNING...TREND WILL CONTINUE INTO THE AFTERNOON
AHEAD OF THE INCOMING FRONTAL SYSTEM. LIGHT RAIN WILL SPREAD INTO
THE INTERIOR FROM THE COAST BY EARLY EVENING...WITH ALL AREAS
LOWERING TO MVFR AND LOCAL IFR BY LATE THIS EVENING AS PRECIPITATION
INCREASES.

KSEA...SOUTH WIND 5-10 KT BECOMING SOUTHWEST 6-12 KT THIS AFTERNOON.

&&

.MARINE...A SURFACE RIDGE WILL REMAIN OVER THE FORECAST AREA TODAY
AS A WARM FRONT MOVING INTO BRITISH COLUMBIA BRUSHES WESTERN
WASHINGTON. A COLD FRONT WILL DIG DOWN INTO THE REGION FROM THE
NORTHWEST LATE TONIGHT. SMALL CRAFT ADVISORY WINDS WILL DEVELOP OVER
MOST OF THE WATERS BY TONIGHT FOR SOUTHWESTERLY WINDS AHEAD OF THE
COLD FRONT. STRONG ONSHORE FLOW WILL FOLLOW THE COLD FRONT TUESDAY
AND TUESDAY NIGHT. FORECAST PROBLEM IS WHETHER OR NOT POST FRONTAL
ONSHORE FLOW IS STRONG ENOUGH FOR GALE FORCE WINDS IN THE STRAIT AND
ADMIRALTY INLET LATE TUESDAY AFTERNOON OR TUESDAY EVENING. FORECAST
CURRENTLY SUPPORTS HIGH END SMALL CRAFT ADVISORY WINDS.

A SECOND AND SIMILAR FRONTAL SYSTEM WILL AFFECT THE REGION WEDNESDAY
AND THURSDAY. 12Z MODELS STICKING WITH TIMING THE WARM FRONT FOR THE
COAST WEDNESDAY MORNING...FOLLOWED BY THE COLD FRONT LATE WEDNESDAY
NIGHT. THIS SYSTEM WILL BRING ANOTHER BOUT OF SMALL CRAFT ADVISORY
WINDS OVER THE FORECAST AREA...AND POSSIBLY GALES FORCE WINDS. IN
ADDITION WESTERLY SWELL 14 TO 16 FT ARE EXPECTED TO MOVE INTO THE
AREA LATER THURSDAY THROUGH FRIDAY.

&&

.AVALANCHE...THE NEXT STRONG FRONTAL SYSTEM SHOULD ALSO CROSS THE
OLYMPICS AND CASCADES TUESDAY MORNING. STRONG NORTHWEST FLOW
ALOFT...OROGRAPHIC AND CONVERGENCE EFFECTS SHOULD CONTINUE TO
ENHANCE SNOWFALL FOLLOWING THE FRONT IN THE OLYMPICS AND CASCADES ON
TUESDAY. THIS SHOULD LEAD TO A SIGNIFICANTLY INCREASING AVALANCHE
DANGER TUESDAY. AN AVALANCHE WATCH IS CURRENTLY IN EFFECT FOR
TUESDAY. PLEASE VISIT WWW.NWAC.US FOR DETAILS. FERBER

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER STORM WATCH FOR THE OLYMPICS AND NORTH AND CENTRAL
       CASCADES THIS EVENING THROUGH TUESDAY AFTERNOON.
     AVALANCHE WATCH IN EFFECT OF TUE.

PZ...SMALL CRAFT ADVISORY FOR THE COASTAL WATERS AND WEST
     ENTRANCE STRAIT OF JUAN DE FUCA NOON TODAY THROUGH TUESDAY.

WWW.WEATHER.GOV/SEATTLE