FXUS66 KMFR 152207
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
205 PM PST TUE DEC 15 2009

.DISCUSSION...
A SLOW MOVING COLD FRONT HAS STARTED TO MOVE INLAND THIS AFTERNOON. 
HIGH WINDS AT THE COAST WILL BEGIN TO DIMINISH AND TAPER OFF 
THROUGH THE EVENING SO THE HIGH WIND WARNING AT THE COAST WILL BE 
ALLOWED TO EXPIRE AT 300 PM THIS AFTERNOON.

MODERATE TO HEAVY SNOWS FALLING IN THE MT SHASTA AREA WILL DIMINISH 
THIS AFTERNOON AS THE COLD FRONT MOVES INLAND RESULTING IN DECREASED
WINDS AND SNOW FALL RATES. SNOW LEVELS HAVE BEEN RISING AS WELL SO
THE WARNING WILL BE ALLOWED TO EXPIRE AT 300 PM AS WELL. THE SAME
REASONING APPLIES TO THE HIGHER PORTIONS OF THE SHASTA VALLEY AND
THE SISKIYOU AND SOUTHERN OREGON CASCADES. THE SNOW ADVISORIES FOR
THESE AREAS WILL EXPIRE AT 300 PM AS WELL.

SNOW ADVISORIES FOR PORTIONS OF KLAMATH LAKE AND MODOC COUNTIES WILL
REMAIN IN EFFECT SINCE THEY ARE LOCATED WELL TO THE EAST OF THE
COLD FRONT AT THIS TIME. SNOW FALL RATES WILL DECREASE THERE LATE
THIS EVENING AS THE COLD FRONT WEAKENS ONCE IT IS WELL INLAND. THE
SAME IS TRUE FOR THE WIND ADVISORY IN THE SHASTA VALLEY WHERE WINDS
WILL TAPER OFF LATER THIS EVENING AS THE FRONT WEAKENS.

LATE TONIGHT WINDS PRECIPITATION BECOME LIGHT AS THE COLD FRONT 
BECOMES QUITE WEAK. WEAK MID LEVEL DISTURBANCES KEEPS LIGHT 
PRECIPITATION GOING THROUGH WEDNESDAY.

THURSDAY A WARM FRONT BRINGS MORE LIGHT PRECIPITATION WITH SNOW
LEVELS AROUND 5000 FEET. THURSDAY NIGHT A WEAK COLD FRONT MOVES
THROUGH THE AREA. FRIDAY AND SATURDAY WEAK MID LEVEL DISTURBANCES
KEEP THE REGION CLOUDY AND THERE WILL BE LIGHT PRECIPITATION OFF
AND ON.

NEXT MONDAY AND TUESDAY A STRONGER LOW PRESSURE SYSTEM WILL LIKELY
AFFECT OUR AREA.

&&

.AVIATION...WITH A SLOW MOVING COLD FRONT ACROSS THE REGION 
GENERALLY MVFR CIGS AND VSBY IN RAIN AND SNOW AREA WIDE THROUGH
THIS EVENING. IFR CIGS VSBY IN SNOW OVER THE HIGHER TERRAIN. 
ALSO...LOCAL LOW LEVEL WIND SHEAR WILL AFFECT THE COAST AND INLAND 
PROTECTED VALLEYS AS UPPER WINDS REMAIN STRONG THROUGH THIS EVENING. 
CONDITIONS WILL IMPROVE WEDNESDAY. LATE TONIGHT THE COLD FRONT
WEAKENS AND PRECIPITATION DECREASES. ON WEDNESDAY MOST AREAS WILL
BE VFR WITH ISOLD OBSCUREMENT OF HIGHER RIDGES.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING FOR ORZ030-
     ORZ031.
     HIGH WIND WARNING UNTIL 10 PM PST THIS EVENING FOR ORZ031.
     HIGH WIND WARNING UNTIL 1 PM PST THIS AFTERNOON FOR ORZ021-
     ORZ022.
     WINTER WEATHER ADVISORY UNTIL 3 PM PST THIS AFTERNOON FOR 
     ORZ027-ORZ028-ORZ029.

CA...WINTER WEATHER ADVISORY UNTIL 10 PM PST THIS EVENING FOR CAZ085.
     WINTER WEATHER ADVISORY UNTIL 3 PM PST THIS AFTERNOON FOR 
     CAZ084.
     WINTER STORM WARNING UNTIL 3 PM PST THIS AFTERNOON FOR CAZ082-
     CAZ083.
     WIND ADVISORY UNTIL 10 PM PST THIS EVENING FOR CAZ081.

PACIFIC COASTAL WATERS...GALE WARNING UNTIL 10 PM PST THIS EVENING 
     FOR PZZ350-PZZ356-PZZ370-PZZ376.
     HAZARDOUS SEAS WARNING UNTIL 4 AM PST THURSDAY FOR 
     PZZ350-PZZ356-PZZ370-PZZ376.

$$

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