Snow In The Forecast
Thursday, April 17, 2008
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE PORTLAND OR
150 PM PDT THU APR 17 2008
150 PM PDT THU APR 17 2008
...UNSEASONABLY COLD WEATHER WITH VERY LOW SNOW LEVELS AND NEAR
RECORD LOW TEMPERATURES IN STORE FOR SOUTHWEST WASHINGTON AND
NORTHWEST OREGON THIS WEEKEND..
ALL OF NORTHWEST OREGON AND SOUTHWEST WASHINGTON WILL BE AFFECTED
BY AN UNUSUALLY COLD SPRING WEATHER SYSTEM THIS WEEKEND. THIS
SYSTEM WILL BRING SIGNIFICANT SNOW TO THE MOUNTAINS AND
FOOTHILLS...ACCUMULATING SNOW TO ELEVATIONS AS LOW AS 1000
FT...AND NEAR RECORD COLD OVERNIGHT LOWS TO THE VALLEY FLOOR.
THE TIMING OF THE COLD WEATHER IS LATE FRIDAY THROUGH MONDAY. THE
SHARPEST DROPS IN TEMPERATURES WILL OCCUR FRIDAY NIGHT INTO
SATURDAY. SNOW LEVELS WILL APPROACH VALUES MORE IN KEEPING WITH
MID WINTER THAN EARLY SPRING. THE SNOW LEVELS WILL CERTAINLY
DESCEND TO THE LOWER FOOTHILLS...AND ITS POSSIBLE THAT NON
ACCUMULATING SNOW COULD FALL AT ELEVATIONS OF 500 FT OR LESS.
THE COLDEST MORNING LOWS WILL BE ON SUNDAY AND MONDAY. THESE
TEMPERATURES ARE GOING TO CHALLENGE RECORDS AT A FEW LOCATIONS AND
WILL BE COLD ENOUGH TO HARM TENDER VEGETATION.
THIS WEEKEND...DO PROTECT ANY VULNERABLE SPRING PLANTS...AND PREPARE
FOR MID WINTER LIKE CONDITIONS IF TRAVELING THROUGH THE MOUNTAINS
AND FOOTHILLS.
PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
422 PM PDT THU APR 17 2008
...UNSEASONABLY COOL SPRING WEATHER CONTINUES...
AS OF APRIL 16TH...THE AVERAGE TEMPERATURE SO FAR FOR THE MONTH OF
APRIL AT SEA-TAC INTERNATIONAL AIRPORT...THE OFFICIAL CLIMATE SITE
FOR SEATTLE...WAS BEEN 46.8 DEGREES. THE FOLLOWING IS THE TOP FIVE
COOLEST APRILS ON RECORD FOR SEA-TAC.
AVERAGE YEAR
44.6 1955
45.4 1948
45.6 1954
45.8 1975
46.1 1970
THE NORMAL AVERAGE TEMPERATURE FOR THE MONTH OF APRIL IS 50.2
DEGREES.
THE LATEST DATE OF SNOWFALL ON RECORD FOR SEA-TAC WAS APRIL 17TH...
SET BACK IN 1972. ON THAT DATE 1.2 INCHES OF SNOW FELL AT THE
AIRPORT. ON APRIL 16TH OF THAT YEAR...1.1 INCHES OF SNOW HAD FALLEN.
THE FOLLOWING ARE STATISTICS FOR OLYMPIA.
THE TOP FIVE COOLEST APRILS ON RECORD ARE AS FOLLOWS.
AVERAGE YEAR
43.6 1955
43.8 1972
44.0 1975
44.5 1964
44.8 1948 AND 1967
AS OF APRIL 16TH...THE AVERAGE TEMPERATURE IN OLYMPIA SO FAR FOR THE
MONTH OF APRIL WAS 44.1 DEGREES. THE NORMAL AVERAGE TEMPERATURE FOR
APRIL IS 47.4 DEGREES.
THE LATEST DATE OF SNOWFALL ON RECORD FOR OLYMPIA WAS APRIL 12TH...
BACK IN 1972. ON THAT DATE...1.8 INCHES OF SNOW FELL. HOWEVER THE
LATEST DATE OF FROZEN PRECIPITATION...OF ANY TYPE...ON RECORD WAS
APRIL 30TH...SET BACK IN 1988. ON THAT DATE...A TENTH OF AN INCH OF
SLEET OR ICE PELLETS FELL.
BELOW NORMAL TEMPERATURES ARE FORECAST FOR WESTERN WASHINGTON THE
REST OF THIS WEEKEND THROUGH AT LEAST THE FIRST HALF OF NEXT WEEK.
HIGH TEMPERATURES WILL TO BE IN THE 40S ACROSS MUCH OF THE LOWLANDS
FRIDAY THROUGH THIS WEEKEND...WITH MINIMUMS ANTICIPATED TO BE IN THE
UPPER 20S TO MID 30S. THESE READINGS ARE COMPARABLE TO WHAT IS NORMAL
DURING FEBRUARY.
A COLD AIR MASS OVER THE AREA FRIDAY AND THIS WEEKEND WILL RESULT IN
THE POTENTIAL FOR SNOW OR A RAIN AND SNOW MIX ACROSS THE LOWLANDS...
PARTICULARLY DURING THE LATE NIGHT AND EARLY MORNING HOURS.
THE LATEST OUTLOOK FROM THE CLIMATE PREDICTION CENTER INDICATED THAT
LA NINA WILL CONTINUE FOR THE NEXT THREE MONTHS. TYPICALLY...LA NINA
EPISODES TRANSLATE TO COOLER AND WETTER THAN NORMAL CONDITIONS FOR
WESTERN WASHINGTON. FOR CLIMATE OUTLOOKS AND MORE INFORMATION ON LA
NINA...VISIT WWW.CPC.NCEP.NOAA.GOV.
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SEATTLE WA
1010 AM PDT THU APR 17 2008
WAZ001-503>519-181200-
SAN JUAN COUNTY-WESTERN WHATCOM COUNTY-SOUTHWEST INTERIOR-
EAST PUGET SOUND LOWLANDS-WESTERN SKAGIT COUNTY-EVERETT AND VICINITY-
SEATTLE/BREMERTON AREA-TACOMA AREA-ADMIRALTY INLET AREA-
HOOD CANAL AREA-LOWER CHEHALIS VALLEY AREA-OLYMPICS-
EASTERN STRAIT OF JUAN DE FUCA-WESTERN STRAIT OF JUAN DE FUCA-
NORTH COAST-CENTRAL COAST-WEST SLOPES NORTHERN CASCADES AND PASSES-
WEST SLOPES CENTRAL CASCADES AND PASSES-
1010 AM PDT THU APR 17 2008
...UNUSUALLY COLD WEATHER IS EXPECTED FRIDAY THROUGH EARLY NEXT WEEK..
A VERY COLD UPPER LEVEL LOW PRESSURE SYSTEM MOVING SOUTHEAST FROM
THE GULF OF ALASKA WILL MOVE INTO THE AREA FRIDAY AND WILL LINGER
THROUGH EARLY NEXT WEEK. THIS UPPER LEVEL LOW WILL GIVE QUITE COOL
AND UNSTABLE CONDITIONS TO THE AREA FRIDAY THROUGH THE WEEKEND.
WHILE DRIER AIR WILL BEGIN TO FILTER INTO THE AREA LATER SUNDAY
INTO MONDAY...TEMPERATURES WILL REMAIN UNUSUALLY COOL FOR MID TO
LATE APRIL.
AT THIS TIME OF YEAR...TEMPERATURES IN THE LOWLANDS TYPICALLY
RANGE FROM LOWS 35 TO 45. ..AND HIGHS ARE NEAR 60. LOW TEMPERATURES ON
FRIDAY...SATURDAY AND SUNDAY...WILL GENERALLY BE IN THE 30S...WITH
THE COLDER LOCATIONS FALLING INTO THE UPPER 20S BY SUNDAY. HIGHS
WILL BE MOSTLY IN THE 40S FRIDAY AND SATURDAY. A LITTLE WARMER
CONDITIONS ARE EXPECTED ON SUNDAY WITH HIGHS NEAR 50. THESE
TEMPERATURES ARE MORE TYPICAL OF EARLY TO MID FEBRUARY. RECORD LOW
MAXIMUM TEMPERATURES ARE POSSIBLE ALL THREE DAYS. TEMPERATURES IN
THE MOUNTAINS WILL STAY IN THE 20S AND LOWER 30S.
SNOW LEVELS FRIDAY MORNING THROUGH SATURDAY MORNING WILL AVERAGE
AROUND 1000 FEET...AND MAY FALL TO NEAR SEA LEVEL IN HEAVIER
SHOWERS DURING THE NIGHT AND EARLY MORNING HOURS. ANY SNOW THAT
FALLS IN THE LOWLANDS IS UNLIKELY TO STICK...EXCEPT BRIEFLY ON
CARS AND GRASS. THE MOUNTAINS AND CASCADE PASSES WILL SEE
ACCUMULATING SNOW FRIDAY THROUGH SATURDAY...WITH ACCUMULATIONS
NEAR 1 FOOT OVER THE 2 DAY PERIOD.
STRONG HIGH PRESSURE DEVELOPING OVER BRITISH COLUMBIA SUNDAY
INTO EARLY NEXT WEEK WILL ALLOW DRIER AIR TO FILTER INTO THE AREA.
DAYTIME TEMPERATURES WILL MODERATE INTO THE LOWER TO MID 50S MONDAY.
NIGHTTIME LOWS WILL STILL BE QUITE COOL FOR THIS TIME OF YEAR WITH
THE COLDER LOCATIONS BELOW FREEZING THROUGH TUESDAY MORNING.
FROST...WITH FREEZING NIGHTTIME TEMPERATURES IN PROTECTED AND
OUTLYING AREAS WILL LIKELY CAUSE PROBLEMS FOR ANYONE WITH SENSITIVE
NURSERY STOCK...ORNAMENTALS...OR VEGETABLES THAT WERE PLANTED EARLY.
MONITOR THE FORECASTS FROM THE NATIONAL WEATHER SERVICE CLOSELY THE
NEXT FEW DAYS.
THE FOLLOWING IS A TABLE OF RECORD LOW MAXIMUM TEMPERATURES FOR
FRIDAY THROUGH SUNDAY FOR SELECTED WESTERN WASHINGTON LOCATIONS.
APRIL 18TH APRIL 19TH APRIL 20TH
SEATTLE 45/1967 47/1975 49/1970
OLYMPIA 48/1973 48/1961 50/1972
BELLINGHAM 47/1973 48/1969 49/1972
FORKS 47/1970 48/1999 48/2006
HOQUIAM 47/1960 46/1955 49/1985
-- posted by Pat Timm @ 9:20 PM,
