HAMweather.com Area Forecast Discussion for County Warning Area SEW

Thu, 16 Feb 2012 06:28:19 GMT
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SEATTLE WA
930 PM PST WED FEB 15 2012

.SYNOPSIS...A WEAKENING FRONTAL SYSTEM WILL MOVE THROUGH THE AREA  
THURSDAY BRINGING AREAS OF LIGHT RAIN. A STRONGER FRONTAL SYSTEM 
WILL ARRIVE FRIDAY AFTERNOON AND NIGHT. A COLD UPPER TROUGH WILL 
GIVE SHOWERS SATURDAY WHICH WILL DIMINISH SUNDAY.

.SHORT TERM...CLOUDS INCREASE TONIGHT AND A WARM FRONT WILL WEAKEN 
AS IT MOVES THROUGH THE AREA THU MORNING. NOT TOO MUCH SURFACE 
REFLECTION OF THIS SYSTEM...A 1007MB LOW IS OVER QUEEN CHARLOTTE 
SOUND 12Z THU WITH THE FRONT TRAILING SOUTH ALONG THE B.C. AND WA 
COAST BUT BY AFTERNOON THERE IS NOTHING MUCH LEFT EXCEPT MAYBE AREAS 
OF DRIZZLE AND A HINT OF A WEAK SURFACE TROUGH. HIGH PRES BUILDS 
INLAND THU NIGHT...BUT IT DOESN'T LOOK LIKE THERE WILL BE ENOUGH 
OFFSHORE FLOW TO DRY THE AIR MASS MUCH. A STRONGER FRONTAL SYSTEM 
ARRIVES LATE FRI AFTERNOON. THAT SYSTEM HAS A NICE BATCH OF COLD AIR 
ALOFT AND SHOULD MAKE FOR DECENT SNOW FRI NITE AND SAT IN THE MTNS. 
19

.LONG TERM...A SERIES OF DISTURBANCES WILL MOVE OVER THE TOP OF A 
RATHER FLAT LONG WAVE RIDGE NEAR 135W SUN NIGHT THROUGH WED. THE 
HIGHEST POPS WILL BE MON NIGHT INTO TUE NIGHT OR WED. THE AIR MASS 
WILL BE RATHER MILD WITH LONG WAVE RIDGING JUST OFFSHORE...BUT THERE 
WILL LIKELY BE ABUNDANT CLOUDS AND SOME LIGHT PRECIPITATION AT 
TIMES. ALBRECHT

.HYDROLOGY...FLOODING IS NOT EXPECTED OVER THE NEXT 7 DAYS. ALBRECHT

.AVIATION...UPPER LEVEL RIDGE SHIFTING EAST TONIGHT WITH FLOW ALOFT 
BECOMING WESTERLY.  

FRONT OFFSHORE MOVING INTO WESTERN WASHINGTON ON THURSDAY. RAIN 
STARTING ALONG THE COAST AROUND 12Z WITH THE RAIN SPREADING INLAND 
15Z-18Z. THE FRONT WILL WEAKEN AS IT MOVES INLAND. JUST SOME HIGH 
LEVEL CLOUDS THIS EVENING. CEILINGS LOWERING DOWN TO 4000 TO 5000 
FEET WITH THE ONSET OF THE RAIN. CEILINGS CONTINUING TO LOWER DOWN 
TO 2000 TO 3000 FEET BY MIDDAY WITH THE RAIN TAPERING OFF IN THE 
AFTERNOON. 

KSEA...CEILINGS LOWERING OVERNIGHT INTO THURSDAY MORNING. CEILINGS 
NEAR 5000 FEET WITH THE ONSET OF RAIN AROUND 15Z. CEILINGS LOWERING 
DOWN TO 2000 TO 3000 FEET MIDDAY. LIGHT WIND OVERNIGHT BECOMING 
SOUTHERLY 6 TO 10 KNOTS THURSDAY MORNING. FELTON

.MARINE...
A FRONTAL SYSTEM WELL OFFSHORE WILL WEAKEN AND MOVE ACROSS THE 
WATERS ON THURSDAY. A STRONG LOW AND ASSOCIATED FRONTAL SYSTEM WILL 
IMPACT THE AREA THE END OF THIS WEEK FOR LARGE WAVES ON THE COASTAL 
WATERS AND THE POSSIBILITY OF GALE FORCE WINDS ACROSS ALL WATERS. 

THE TRACK OF THE SURFACE LOW THAT WILL AFFECT THE AREA THE END OF 
THIS WEEK WAS STILL UNCERTAIN. SOME MODELS TAKE THE SURFACE LOW 
ACROSS THE NORTHERN WASHINGTON COASTAL WATERS WHERE OTHERS TAKE IT 
INTO THE OREGON COASTAL WATERS. THIS WILL HAVE AN IMPACT ON THE WIND 
FORECAST. REGARDLESS OF WHERE THE LOW TRACKS... WAVES OF 19 TO 23 FT 
ARE STILL ANTICIPATED TO ARRIVE ON SATURDAY. THIS WILL RESULT IN 
HAZARDOUS SEAS ON THE COASTAL WATERS AND HIGH SURF ON THE BEACHES. 
FELTON
 

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...NONE.
PZ...SMALL CRAFT ADVISORY UNTIL 6 PM PST THURSDAY FOR THE 
       COASTAL WATERS AND WEST ENTRANCE TO THE STRAIT OF JUAN DE
       FUCA.
     SMALL CRAFT ADVISORY FOR WINDS FROM 6 AM TO 6 PM PST
       THURSDAY FOR THE ADMIRALTY INLET...EAST ENTRANCE TO THE
       STRAIT OF JUAN DE FUCA...AND NORTHERN INLAND WATERS.
     SMALL CRAFT ADVISORY FOR ROUGH BAR UNTIL 6 PM PST THURSDAY
       FOR THE GRAYS HARBOR BAR.