Forecast: Forecast Discussion | 7 Day Forecast

000
FXUS66 KMFR 101209
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
409 AM PST WED MAR 10 2010

.DISCUSSION...A FAST MOVING COLD FRONT MOVED EVEN QUICKER THAN INDICATED
BY THE GFS AND NAM AS IT CROSSED OUR AREA LATE LAST EVENING.
SCATTERED LIGHT SHOWERS AND SNOW SHOWERS IN THE UNSTABLE AIR MASS
BEHIND THE FRONT WILL BE MAINLY ON NORTHWEST FACING SLOPES OF
WESTERN OREGON AND DIMINISH IN COVERAGE THROUGH AROUND 10 AM THIS
MORNING. HIGH PRESSURE WILL BEGIN TO BUILD INTO OUR REGION THIS AFTERNOON.

MID AND HIGH LEVEL CLOUDS WILL BE ON THE INCREASE AGAIN LATE TONIGHT
WHICH IS EXPECTED TO BE SUFFICIENT TO PREVENT THE FORMATION OF
VALLEY LOW CLOUDS AND FOG LATE WEDNESDAY NIGHT. THESE CLOUDS ARE
IN ADVANCE OF THE NEXT FRONT. THIS FRONT WILL BE STRONGER BUT ALSO
WARMER. SOUTH WINDS WILL INCREASE THURSDAY AND BECOME STRONG AT
THE COAST...IN THE SHASTA VALLEY AND LOCALLY OVER THE HIGHER
TERRAIN LATE THURSDAY NIGHT...STRONGEST AS THE FRONT PASSES DURING
THE DAY ON FRIDAY. THUS... A HIGH WIND WATCH HAS BEEN ISSUED FOR
THE COASTAL ZONES AND THE SHASTA VALLEY. SNOW LEVELS WILL BE
MAINLY 4500 TO 5000 FEET BUT LOCALLY LOWER DOWN TO 3500 FEET WITH
HEAVIER PRECIPITATION RATES AT SOUTH AND SOUTHWEST FACING SLOPES
SUCH AS IN WESTERN AND SOUTHERN SISKIYOU COUNTY WHERE A WINTER
STORM WATCH IS IN EFFECT. THE FRONT IS EXPECTED TO BRING
PRECIPITATION TO THE COAST AS EARLY AS THURSDAY MORNING BUT WILL
NOT CROSS THE CASCADES UNTIL EARLY FRIDAY AFTERNOON WITH A FEW
HOURS WORTH OF MODERATE INTENSITY SHOWERS AND SNOW SHOWERS BEHIND
THE FRONT...THEN LIGHT SHOWERS AND SNOW SHOWERS LIKELY THROUGH THE
REMAINDER OF FRIDAY NIGHT.

A RELATIVELY STRONG HIGH PRESSURE RIDGE IS EXPECTED TO BUILD INTO
THE PACIFIC NORTHWEST OVER THE WEEKEND AND PERSIST THROUGH MONDAY. IT
WILL BE DRY EXCEPT FOR A SLIGHT CHANCE OF VERY LIGHT OVERRUNNING
SHOWERS IN COOS AND FAR WESTERN DOUGLAS COUNTIES. THERE WILL BE
PERIODS OF THICK CIRRUS CLOUD COVER ASSOCIATED WITH THE NEXT
FRONT...EXPECTED TO STALL OFFSHORE.

MODEL SOLUTIONS BEGIN TO MORE SIGNIFICANTLY DIVERGE EARLY NEXT
WEEK REGARDING THE EASTWARD PROGRESS...STRENGTH AND TRACK OF THE NEXT
FRONT. THUS...CONFIDENCE IS LOWER THAN USUAL FOR DAYS 6 AND 7 OF
THE FORECAST.


&&

.AVIATION...ISOLATED MVFR CEILINGS AND MOUNTAIN OBSCURATIONS WITH
SHOWERS AND SNOW SHOWERS THIS MORNING...MAINLY WEST OF THE
CASCADE CREST. BECOMING VFR ACROSS THE REGION THIS AFTERNOON.
AREAS OF MVFR DEVELOPING AT THE COAST AGAIN LATE WEDNESDAY NIGHT.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...HIGH SURF ADVISORY UNTIL 4 PM PST THIS AFTERNOON FOR ORZ021-022.
     HIGH WIND WATCH FROM THURSDAY EVENING THROUGH FRIDAY MORNING FOR
     ORZ021-022.

CA...HIGH WIND WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY
     AFTERNOON FOR CAZ081.
     WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY
     AFTERNOON ABOVE 4000 FEET FOR CAZ080-082.
     WINTER STORM WATCH FROM LATE THURSDAY NIGHT THROUGH FRIDAY
     AFTERNOON FOR CAZ083.

PACIFIC COASTAL WATERS...HAZARDOUS SEAS WARNING UNTIL 10 AM PST THIS
     MORNING FOR PZZ350-356-370-376.

$$

DW

NWS MFR Office Area Forecast Discussion