AREA FORECAST DISCUSSION

 
 FXUS66 KMFR 251123
 AFDMFR
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE MEDFORD OR
 323 AM PST WED NOV 25 2009
 
 .DISCUSSION...UPPER LEVEL RIDGE PATTERN WITH WEAK OFFSHORE FLOW
 CONTINUES TO BRING CLEAR SKIES EXCEPT FOR LOW MORNING LOW CLOUDS
 AND FOG IN THE WEST SIDE VALLEYS AND THE KLAMATH BASIN EAST OF THE
 CASCADES. RIDGES REMAIN RELATIVELY WARM AND DRY OVERNIGHT AND
 LOOKS TO CONTINUE ANOTHER NIGHT AS THE FRONT LOOKS LIKE IT WILL
 NOT BRING CLOUDS INTO THE ARE BEFORE A ANOTHER STRONG INVERSION
 SETS UP. THERE ARE SOME MINOR DISAGREEMENTS WITH THE TIMING OF
 THIS SYSTEM WITH THE ECMWF BEING THE FASTEST AND THE GFS...NAM AND
 UKMET IN AGREEMENT ON A SLOWER ONSET OF THE SYSTEM IN OUR AREA AND
 AM LEANING TOWARDS THIS SLOWER SOLUTION AS A RESULT. AM NOT AS
 CONCERNED ABOUT INCREASED PRECIPITATION FROM A WEAK TROPICAL TAP
 THAT APPEARS TO BE DISCONNECTING NEAR HAWAII AND MIGHT STILL BUMP
 UP QPF A BIT FROM WHAT THE MODELS ARE INDICATING. THE MEAT OF THE
 SYSTEM LOOKS TO BE COMING ONSHORE ON THANKSGIVING AFTERNOON ON THE
 NOSE OF A 120 KT JET...MOVING INLAND WITH THE HEAVIEST
 PRECIPITATION THURSDAY NIGHT AS THE LEFT EXIT REGION OF THE JET
 NUDGES INTO SOUTHWEST OREGON. WITH THE INCREASED SOUTHERLY FLOW
 SNOW LEVELS WILL REMAIN ABOVE PASS LEVELS UNTIL THE BULK OF THE
 WARM CONVEYOR PRECIPITATION IS THROUGH AND COMES DOWN TO PASS
 LEVELS IN THE POST FRONTAL SHOWERS. ANOTHER...WEAKER FRONT MOVES
 INTO THE REGION FRIDAY NIGHT IN THE NORTHWESTERLY FLOW ALOFT ON
 THE NOSE OF A NORTHERLY 120 KT JET. HOWEVER...THE STRONGEST JET
 DYNAMICS ARE WELL NORTH OF OUR AREA BRINGING THE HEAVIEST QPF
 NORTH OF OUR AREA AS WELL. A COLDER AIR MASS COMES IN BEHIND THIS
 FRONT BRINGING SNOW LEVELS TO NEAR THE VALLEY FLOORS ON THE WEST
 SIDE BY SATURDAY MORNING. THIS SHOWERS COULD LINGER A BIT SATURDAY
 ON THE EAST SIDE BUT AGAIN THE BEST ACTION IS NORTH OF THE REGION
 AND SNOW AMOUNTS SHOULD NOT BE EXCESSIVE FOR TRAVEL.
 
 
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 .AVIATION...AREAS OF IFR IN THE VALLEYS WEST OF THE CASCADES...VCTY
 KLMT AND THE COAST AGAIN THIS MORNING IN LOW CLOUDS AND FOG
 THROUGH MUCH OF THE MORNING...BEFORE BURNING OFF AGAIN WITH
 SIMILAR TIMING AS YESTERDAY. SIMILAR PATTERN SETS UP MOSTLY INLAND
 TONIGHT AHEAD OF COLD FRONT WITH THE COAST IN MVFR TO VFR AS
 CLOUDS MOVE IN WITH THE FRONT...MOVING INLAND THROUGH THE DAY AND
 LIFTING THE IFR DECKS.
 
 
 &&
 
 .MFR WATCHES/WARNINGS/ADVISORIES...
 OR...HIGH SURF ADVISORY FROM 1 AM THURSDAY TO 7 PM PST FRIDAY FOR 
      ORZ021-ORZ022.
 
 CA...NONE.
 
 PACIFIC COASTAL WATERS...HAZARDOUS SEAS WATCH FROM THURSDAY EVENING 
      THROUGH FRIDAY EVENING FOR PZZ350-PZZ356-PZZ370-PZZ376.
      SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 10 PM THIS EVENING 
      TO 10 PM PST THURSDAY FOR PZZ356.
      SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 PM THIS AFTERNOON 
      TO 10 PM PST THURSDAY FOR PZZ350-PZZ376.
      SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM NOON TODAY TO 10 PM 
      PST THURSDAY FOR PZZ370.
 
 

 
 SVEN