Funnel Cloud in Washington, March 27, 2016

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
900 AM PDT SUN MAR 27 2016

.SYNOPSIS...AN UPPER LEVEL TROUGH WILL GIVE SHOWERS AND A CHANCE OF
AFTERNOON AND EVENING THUNDERSTORMS TODAY. SNOW WILL BE HEAVY AT
TIMES IN THE CASCADES ABOVE 3000 FEET THROUGH TONIGHT. THE AIR MASS
WILL GRADUALLY STABILIZE AND DRY LATE TONIGHT THROUGH MONDAY. A
STRONG UPPER LEVEL RIDGE WILL GIVE MOSTLY SUNNY DAYS AND WARM DAYS
TUESDAY THROUGH SATURDAY.

&&

.SHORT TERM...RADAR SHOWS SCATTERED SHOWERS OVER MOST OF THE AREA
AND ONE BIG BLOB OF CONVERGENCE ZONE PRECIPITATION IN MAINLY
SNOHOMISH COUNTY. THIS CONVERGENCE ZONE IS FORECAST TO SLOWLY MOVE
SOUTH TODAY AND THIS EVENING...THEN DISSIPATE. ALONG WITH THE
SHOWERS TODAY THERE COULD BE A FEW THUNDERSTORMS. THESE ARE SOMEWHAT
MORE LIKELY IN THE CONVERGENCE ZONE.

SNOW WILL FALL IN THE MOUNTAINS UNDER THE CONVERGENCE ZONE AS WELL
SINCE THE SNOW LEVEL IS AROUND 3000 FEET. CURRENTLY THE CONVERGENCE
IS NORTH OF STEVENS PASS...BUT AS THE DAY PROGRESSES FIRST STEVENS
PASS THEN SNOQUALMIE PASS WILL GET SNOW. AROUND A FOOT OF NEW SNOW
SEEMS LIKELY BY THE TIME THE SHOWERS END LATE TONIGHT. A WINTER
WEATHER ADVISORY IS IN EFFECT.

SHOWERS TAPER LATE TONIGHT AS THE UPPER TROUGH CLOSES OFF INTO A LOW
AND MOVES SOUTHEAST INTO SOUTHEASTERN OREGON AND SOUTHERN IDAHO.
SHOWERS MAY TAKE UNTIL MONDAY EVENING TO COMPLETELY COME TO AN END
OVER THE CASCADES AS COOL AND MOIST AIR CONTINUES TO WRAP AROUND THE
UPPER LOW TO THE SOUTHEAST OF THE AREA AND INTO WESTERN WASHINGTON.

TUESDAY WILL SEE CLEAR SKIES WITH NORTHEASTERLY FLOW AT LOWER
LEVELS. BY TUESDAY AFTERNOON TEMPERATURES WILL LIKELY REACH 60
DEGREES IN BRILLIANT SUNSHINE. BURKE

.LONG TERM...PREVIOUS DISCUSSION...TUESDAY NIGHT THROUGH SATURDAY
WILL BE DRY. 500 MB HEIGHTS AROUND 565 DAM TUESDAY AFTERNOON RISE TO
NEAR 575 DAM BY FRIDAY MORNING AS A STRONG UPPER LEVEL RIDGE
INITIALLY OVER THE OFFSHORE WATERS ON TUESDAY GRADUALLY SHIFTS
EASTWARD. EXPECT THE AIR MASS TO GRADUALLY WARM WITH HIGH
TEMPERATURES WELL INTO THE 60S BY THURSDAY AND FRIDAY. SATURDAY MAY
SEE SOME COOLING AS LOW LEVEL FLOW BECOMES ONSHORE IN RESPONSE TO
THE UPPER RIDGE MOVING TO THE EAST OF THE AREA. ALBRECHT

&&

.HYDROLOGY... RIVER FLOODING IS UNLIKELY OVER THE NEXT 7 DAYS.

&&

.AVIATION...AN UPPER LEVEL TROUGH IS OVER THE PACNW. THE AIR IS
MOIST AND UNSTABLE WITH A  CHANCE OF THUNDERSTORMS THIS AFTERNOON
AND EARLY EVENING. A PUGET SOUND CONVERGENCE ZONE IS OVER SNOHOMISH
COUNTY AT 8AM. IN STRONG ONSHORE FLOW IT WILL BE MOSTLY CLOUDY
ACROSS WESTERN WA...CIGS SHOULD LIFT A BIT INTO THE AFTERNOON.
THE MOUNTAINS WILL REMAIN OBSCURED INTO THIS EVENING.

KSEA...THE PSCZ SHOULD STAY UP AROUND THE KING SNO COUNTY LINE
THIS MORNING...BUT IT MAY DRIFT DOWN CLOSER TO THE CITY IN THE
AFTERNOON. THE WIND SHOULD STAY SW FOR A GOOD PART OF THE DAY
BUT SHOULD BECOME LIGHT AND VARIABLE AS THE PSCZ DROPS SOUTH
THIS AFTERNOON OR EVENING.

&&

.MARINE...STRONG ONSHORE FLOW TODAY IN THE WAKE OF A COLD FRONT.
A PUGET SOUND CONVERGENCE ZONE WILL BE ACTIVE TODAY. GALES ARE
BLOWING IN THE STRAIT AND WINDS OVER THE COASTAL WATERS HAVE
BEEN NW 20-30KT. THE ONSHORE FLOW WILL EASE THIS EVENING AND
STRONG HIGH PRESSURE WILL BUILD OVER THE REGION MON THRU WED.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 5 AM PDT
     MONDAY FOR CASCADES OF PIERCE AND LEWIS COUNTIES-CASCADES
     OF SNOHOMISH AND KING COUNTIES-CASCADES OF WHATCOM AND
     SKAGIT COUNTIES.

PZ...SMALL CRAFT ADVISORY ALL WATERS EXCEPT GALE WARNING CENTRAL
      AND EASTERN STRAIT OF JUAN DE FUCA.
     SMALL CRAFT ADVISORY GRAYS HARBOR BAR.

&&

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