000
FXUS66 KMFR 240413
AFDMFR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
815 PM PST MON NOV 23 2009

.SHORT TERM...DRY WEATHER IS IN STORE AS WEAK HIGH PRESSURE OVER THE
REGION WILL GRADUALLY STRENGTHEN THROUGH WEDNESDAY. EXPECT AREAS OF
FOG TO DEVELOP IN THE VALLEYS OF SOUTHWEST OREGON AND WESTERN
SISKIYOU COUNTY CALIFORNIA LATE TONIGHT OR EARLY TUESDAY MORNING.
MOST LOCATIONS SHOULD CLEAR OUT BY EARLY AFTERNOON. VALLEY FOG WILL
LIKELY DEVELOP AGAIN LATE TUESDAY NIGHT OR EARLY WEDNESDAY MORNING.

HIGH PRESSURE WILL WEAKEN WEDNESDAY NIGHT AS A COLD FRONT SLOWLY
APPROACHES THE COAST. THE LATEST TIMING BRINGS THE FRONT TO THE
COAST THURSDAY AFTERNOON THEN INLAND DURING THE EVENING. SOUTHERLY
WINDS IN ADVANCE OF THE FRONT WILL INCREASE ALONG THE COAST BUT ARE
EXPECTED TO REMAIN BELOW WARNING CRITERIA. AS FAR AS RAINFALL TOTALS
WITH THIS SYSTEM...NOT THAT IMPRESSIVE FOR THIS TIME OF YEAR.
PORTIONS OF THE COAST COULD GET BETWEEN ONE AND TWO INCHES...THEN
DROPPING OFF THE FURTHER INLAND YOU GO. SNOW LEVELS WILL LOWER TO
AROUND PASS LEVEL BY LATE THURSDAY NIGHT WITH THE POTENTIAL OF 3 TO
6 INCHES OF SNOW ACCUMULATION IN THE CASCADES AND SISKIYOUS.

.LONG TERM...AFTER THE LOW PRESSURE SYSTEM EXITS THE AREA FRIDAY
MORNING...BOTH THE GFS AND ECMWF DO NOT WASTE ANY TIME BRINGING IN
ANOTHER SHORTWAVE TROUGH THROUGH FRIDAY NIGHT INTO SATURDAY.  RAIN
AND SNOW AMOUNTS WILL LIKELY BE LIGHT TO MODERATE WITH THIS
FEATURE...BUT RUN TO RUN CONSISTENCY IS NOT GOOD...AND THERE IS LOW
CONFIDENCE IN THE MODEL SOLUTIONS.  SNOW LEVELS REMAIN AROUND 4000
FEET THROUGH SATURDAY MORNING AND THEN BEGIN TO RISE SUNDAY THROUGH
TUESDAY WITH UPPER RIDGING BUILDING ACROSS THE AREA.  ANOTHER FAIRLY
DRY PERIOD WITH MORNING VALLEY FOG AND AFTERNOON SUN IS LIKELY
SUNDAY THROUGH EARLY TUESDAY.  RECENT MODEL TRENDS TEND TO DEEPEN
THE TROUGHS EARLY NEXT WEEK OVER THE CENTRAL PLAINS AND AROUND 140W
OVER THE EPAC WATERS...WHICH SHOULD YIELD DRY AND WARMER WEATHER
OVER CALIFORNIA AND OREGON.  CPC 6-10 DAY OUTLOOK REFLECTS THIS
IDEA.

&&

.AVIATION...INTERIOR VALLEY FOG WILL DEVELOP LATE TONIGHT FOR AREAS
OF IFR CONDITIONS...OTHERWISE EXPECT VFR CONDITIONS AROUND THE
REGION OVERNIGHT.

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...NONE.

CA...NONE.

PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS
UNTIL 10 PM PST TUESDAY FOR PZZ350-PZZ356-PZZ370-PZZ376.

$$

RH/MP/NK/11