Hail in Washington, April 15, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
230 PM PDT SAT APR 15 2006

.SYNOPSIS...A WEATHER SYSTEM WILL MOVE INLAND TONIGHT WITH SHOWERS
AND BREEZY WINDS DECREASING. A COOL UPPER TROUGH WILL KEEP SHOWERS
IN THE FORECAST THROUGH THE FIRST PART OF NEXT WEEK. HIGH PRESSURE
WILL BUILD OVER THE AREA TUESDAY AND THEN MOVE EAST ON WEDNESDAY
PROVIDING A COUPLE OF DRY DAYS BEFORE THE NEXT SYSTEM MOVES THROUGH
LATE NEXT WEEK.

&&

.SHORT TERM...SHORT WAVE CURRENTLY MOVING THROUGH. EXPECT SOME
BREEZY OR WINDY CONDITIONS BEHIND THIS FEATURE THIS EVENING AS A 990
MB LOW MOVES INTO CENTRAL VANCOUVER ISLAND. SHOWERS WILL TAPER AFTER
THE WAVE MOVES THROUGH...BECOMING SCATTERED AFTER MIDNIGHT. SNOW IN
THE MOUNTAINS SHOULD TAPER AS WELL AFTER MIDNIGHT. SNOW ADVISORY FOR
THE CASCADES UNTIL 11 PM COVERS THIS. AN UPPER TROUGH OVER THE AREA
WILL WEAKEN AND SPLIT ON SUNDAY AS JET ENERGY DIVES INTO CALIFORNIA.
THE AIR OVER WESTERN WASHINGTON WILL REMAIN UNSTABLE BUT SHOWERS
WILL BE LESS NUMEROUS WITH NO FOCUSSED DYNAMICS. AN UPPER RIDGE WILL
BUILD IN FROM THE WEST ON MONDAY. THIS WILL CONTINUE THE DRYING
TREND BUT A FEW SHOWERS WILL LIKELY LINGER. TUESDAY SHOULD BY DRY
WITH THE RIDGE OVERHEAD. HAVE LEFT A SMALL CHANCE OF RAIN AT THE
COAST AS A WEAKENING FRONT TRIES TO APPROACH FROM THE WEST. HIGHS
WILL MODERATE A LITTLE ON SUNDAY BUT REMAIN A LITTLE BELOW NORMAL.
CONTINUED MODERATION MONDAY WITH HIGHS NEAR 60 MANY AREAS BY
TUESDAY. SCHNEIDER

.LONG TERM...UPPER RIDGE AXIS WILL SHIFT INLAND WEDNESDAY. GFS NOW
BRINGS RAIN INTO WESTERN WASHINGTON LATER WEDNESDAY...FASTER THAN
PREVIOUS RUNS. CONSENSUS HAS BEEN TO LEAVE THE CURRENT DRY FORECAST
ALONE FOR NOW SINCE CONFIDENCE IN TIMING IS LOW. AN UPPER TROUGH
WILL MOVE THROUGH THURSDAY AND FRIDAY AND HAVE SOME PRECIPITATION IN
THE FORECAST FOR THIS. GFS SHOWS SATURDAY DRY WITH HIGH PRESSURE BUT
HAVE LUMPED THIS DAY WITH THURSDAY AND FRIDAY FOR NOW SINCE
CONFIDENCE IN DETAILS IS LOW. SCHNEIDER

&&

.AVIATION...AREAS OF RAIN TURN TO SHOWERS WITH THE PASSAGE OF THE
TROF. WIND SHIFT FROM SE TO SW KSEA AROUND 00Z...SHOULD BE GUSTING
AROUND 30 KTS THROUGH THE EVENING. STRONG ONSHORE FLOW TONIGHT IN AN
UNSTABLE AIR MASS SHOULD MAKE FOR AREA OF MVFR CIGS IN SHOWERS. A
FEW ICE PELLET SHOWERS POSSIBLE OVERNIGHT AS VERY COLD AIR ALOFT
MOVES OVER THE AREA.

&&

.MARINE...GALES COAST AND ENTRANCES TO THE STRAIT. IT HAS A GOOD
SHOT OF BLOWING GALE THIS EVENING OVER THE INLAND WATERS AS WELL AS
THE 990MB LOW MOVES NORTH OVER VANCOUVER ISLAND AND OUR GRADIENT
INCREASES...PEAK WINDS AROUND PUGET SOUND OUGHT TO BE AROUND 9PM. MM

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
.GALE WARNING ALL WATERS EXCEPT SMALL CRAFT ADVISORY IN THE CENTRAL
STRAIT.
.SNOW ADVISORY CASCADES AND OLYMPICS UNTIL 11 PM THIS EVENING.

WEATHER.GOV/SEATTLE