Brief high wind in the Enumclaw area.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS SEW wrote it up.
Brief high wind in the Enumclaw area.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Seattle, WA wrote its last area forecast discussion before the first event at Mar 20, 2:00 PM PST, 0 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
300 PM PDT SUN MAR 20 2011
.SYNOPSIS...A WEAK UPPER TROUGH WILL REMAIN JUST OFFSHORE TONIGHT
AND MONDAY...THEN WEAKEN AND SHIFT INLAND TUESDAY. THIS PATTERN WILL
BRING MOSTLY CLOUDY SKIES TO WESTERN WASHINGTON AND GENERALLY LIGHT
SPOTTY SHOWERS. WEDNESDAY WILL BE PARTLY SUNNY AND GENERALLY DRY.
ANOTHER UPPER TROUGH WILL MOVE INTO THE OFFSHORE WATERS THURSDAY AND
KEEP A MENTION OF SHOWERS IN THE FORECAST THROUGH THE WEEKEND.
&&
.SHORT TERM...AN UPPER LEVEL TROUGH REMAINS OVER THE OFFSHORE WATERS
OF THE PACIFIC NORTHWEST AND CALIFORNIA THIS AFTERNOON...WITH A
VORTICITY LOBE WEAKENING AS IT LIFTS SLOWLY NORTHWARD THROUGH
OREGON. THE COMMA FEATURE THAT WAS ASSOCIATED WITH THIS HAS MORE OR
LESS FALLEN APART DURING THE DAY...WITH SHOWERS BECOMING LIGHT AND
WIDELY SCATTERED AS THEY MOVE INTO WESTERN WASHINGTON. THUS LITTLE
IN THE WAY OF LOWLAND PRECIPITATION HAS MADE IT NORTH OF THE
SOUTHERN PUGET SOUND REGION. OFFSHORE PRESSURE GRADIENTS PEAKED
MIDDAY TODAY...AND THIS IS PRODUCING LOCALLY GUSTY EAST WINDS ALONG
THE WEST SLOPES OF THE CASCADES.
THE OFFSHORE TROUGH HAS BEEN GRADUALLY SPLITTING OVER THE PAST
DAY...WITH ONE LOW CENTERED OFF THE COAST OF CENTRAL CALIFORNIA AND
ANOTHER LOW OVER THE WASHINGTON OFFSHORE WATERS. THE LOW OFF
CALIFORNIA WILL WEAKEN AS IT MOVES INLAND ACROSS CALIFORNIA
TONIGHT...LEAVING A WEAK POORLY DEFINED UPPER TROUGH ALONG THE COAST
OF BRITISH COLUMBIA AND THE PACIFIC NORTHWEST TONIGHT AND MONDAY. AT
LOWER LEVELS...THE NORTHERLY OFFSHORE FLOW PEAKED MIDDAY TODAY. IT
WILL WEAKEN TONIGHT AND TURN WEAKLY ONSHORE MONDAY. SO LIGHT MOIST
SOUTHERLY FLOW ALOFT AND VERY WEAK INSTABILITY WILL KEEP SKIES
MOSTLY CLOUDY AND PRODUCE SCATTERED LIGHT SHOWERS.
ONSHORE FLOW WILL INCREASE SOMEWHAT MONDAY AFTERNOON AND THE UPPER
TROUGH WILL START TO MOVE INLAND. THIS SUBTLE CHANGE COULD BE ENOUGH
TO CAUSE A WEAK PUGET SOUND CONVERGENCE ZONE TO DEVELOP...AS MOST OF
THE MODELS ARE INDICATING. IT WILL NOT BE AN ESPECIALLY SIGNIFICANT
FEATURE...BUT IT MIGHT GIVE SOME ORGANIZATION TO THE OTHERWISE
RANDOMLY HIT AND MISS SHOWERS. IF THE CONVERGENCE ZONE DOES FORM IT
WILL PROBABLY LAST INTO MONDAY NIGHT AND DISSIPATE OVERNIGHT AS
ONSHORE FLOW WEAKENS.
THE UPPER TROUGH WILL WEAKEN AND SHIFT FURTHER INLAND TUESDAY...AND
LOW LEVEL ONSHORE FLOW WILL ESSENTIALLY END AS A FRONTAL SYSTEM
MOVES TOWARD CALIFORNIA FROM THE WEST. FOR WESTERN WASHINGTON IT
WILL MEAN LITTLE CHANGE IN THE WEATHER. IT WILL BE ANOTHER DAY WITH
MOSTLY CLOUDY SKIES AND SCATTERED LIGHT SHOWERS.
WEDNESDAY WILL BE A MOSTLY DRY AND PARTLY SUNNY DAY FOR OUR FORECAST
AREA...ESPECIALLY OVER THE WESTERN WASHINGTON LOWLANDS. THE FRONTAL
SYSTEM MENTIONED ABOVE WILL MOVE INLAND ACROSS CALIFORNIA AND
OREGON...WHILE ANOTHER UPPER TROUGH APPROACHES THE REGION FROM THE
WEST. MCDONNAL
.LONG TERM...DISAGREEMENT BETWEEN MODELS...POOR RUN TO RUN
CONSISTENCY...AND LACK OF CONFIDENCE IN DETAILS FINER THAN THE LARGE
SCALE PATTERN HAVE NECESSITATED A BROAD BRUSH APPROACH TO THE LONG
TERM FORECAST FOR SEVERAL DAYS NOW. UNFORTUNATELY THAT IS STILL THE
CASE TODAY.
THE GFS KEEPS A WEAK UPPER TROUGH OVER THE REGION THURSDAY AND
FRIDAY...FOLLOWED BY A MINOR RIDGE SATURDAY AHEAD OF A WELL
DEVELOPED FRONTAL SYSTEM ON SUNDAY. THAT SCENARIO LOOKS REASONABLE
ENOUGH...BUT DIFFERS FROM PREVIOUS RUNS OF THE MODEL. IN ADDITION
THE EUROPEAN MODEL IS LEANING TOWARD THE IDEA OF A DEEPER CLOSED LOW
JUST OFFSHORE THURSDAY THROUGH SATURDAY...WITH IT THEN SWINGING
INLAND ON SUNDAY. HENCE THE FORECAST WILL REMAIN QUITE GENERAL AND
REFLECT A BLEND OF CLIMATOLOGY AND MODEL GUIDANCE. MCDONNAL
&&
.HYDROLOGY...NO WEATHER SYSTEM CAPABLE OF FLOOD-PRODUCING HEAVY RAIN
OVER WESTERN WASHINGTON IS IN THE FORECAST FOR THE NEXT TEN DAYS. IT
SHOULD ALSO BE NOTED THAT MAJOR RIVER FLOODING EPISODES IN WESTERN
WASHINGTON ARE VERY RARE AFTER MID-MARCH. FLOODING IS UNLIKELY ON
ANY RIVER...INCLUDING THE GREEN RIVER. MCDONNAL
&&
.AVIATION...AN UPPER LOW IS TRANSITIONING TO AN OPEN TROUGH AS IT
SLOWLY DRIFTS INLAND ALONG THE NORTHERN CALIFORNIA COASTLINE. THE
FLOW ALOFT IS STILL FROM THE SOUTH...AND THE AIR MASS IS DRY AND
STABLE AT THE LOW LEVELS...WITH SOME INSTABILITY AND INCREASED
MOISTURE AT THE MID AND UPPER LEVELS. NORTHERLY OFFSHORE FLOW
CONTINUES TO PRODUCE A GOOD BREEZE THROUGH THE SOUND AND EASTERLY
WINDS AT KHQM AND KCLM.
THE LOW IS ROTATING RAIN BANDS NORTHWARD THROUGH OREGON BUT WITH DRY
NORTHERLY OFFSHORE FLOW AT THE SURFACE AND DEWPOINTS STILL
PREDOMINATELY IN THE 30S...WESTERN WA REMAINS DRY. THE TROUGH AXIS
WILL SLIDES CLOSER TO THE WA COAST BY MONDAY MORNING WITH THE
OFFSHORE FLOW ABATING TONIGHT AND BECOMING ONSHORE MONDAY. THE LOWER
LEVELS WILL BEGIN TO MOISTEN TONIGHT AND MONDAY SHOULD SEE MORE IN
WAY OF LOWER CIGS AND RAIN.
KSEA...N - NE WINDS AROUND 15 KT THROUGH 00-02Z...EASING OVERNIGHT.
CHANCE OF SHOWERS INCREASING AFTER 06Z. DAMICO
&&
.MARINE...A 996 MB LOW CONTINUES TO SLOWLY MOVE INTO NORTHERN
CALIFORNIA. AN INVERTED TROUGH OF LOW PRES EXTENDS UP TO THE
WASHINGTON COAST...MAINTAINING OFFSHORE FLOW. AS THE LOW PASSES
FURTHER INLAND TONIGHT...OFFSHORE FLOW WILL WEAKEN. OLM-BLI
GRADIENTS HAVE PEAKED AT OVER -4 MB...AND ARE STARTING TO COME DOWN
THIS AFTERNOON. HOWEVER...SMALL CRAFT ADVISORY LEVEL WINDS CONTINUE
TO BE OBSERVED FOR NEARLY ALL WATERS...EXCLUDING THE EAST ENTRANCE
WHICH IS PARTIALLY SPARED BY THE SAN JUANS. HAVE EXPANDED AND
EXTENDED SCA FOR WINDS THROUGH 9 PM.
A WEAK TROUGH APPROACHING FROM THE WEST AND SURFACE HIGH PRES
BUILDING BEHIND IT WILL TURN GRADIENTS ONSHORE MONDAY AFTERNOON.
LIGHT SOUTHERLY WINDS TUESDAY WILL TURN OFFSHORE ONCE AGAIN IN THE
MIDDLE OF WEEK AS ANOTHER SYSTEM APPROACHES OFFSHORE AND DIVES SOUTH
TOWARD CALIFORNIA.
DAMICO
&&
.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY IN EFFECT ALL WATERS EXCEPT EAST ENTRANCE
FOR THE STRAIT OF JUAN DE FUCA.
WWW.WEATHER.GOV/SEATTLE
FOR AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION PLEASE SEE
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML (ALL LOWERCASE)PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SEATTLE WA
254 PM PDT SUN MAR 20 2011
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0254 PM NON-TSTM WND GST 4 WNW ENUMCLAW 47.23N 122.06W
03/20/2011 M60 MPH KING WA TRAINED SPOTTER
NORTHEAST SUSTAINED WINDS OF 40 MPH.
&&
GRUB1 high wind. Local standard time, as filed.
Spotter near Enumclaw reported sustained 40 mph wind gusting to 60 mph.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Washington in 2011Every state in 2011This day in weather historyWarnings in Washington, March 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 293459.