118  
FXUS66 KMFR 191324 CCA  
AFDMFR  
 
AREA FORECAST DISCUSSION...CORRECTED  
NATIONAL WEATHER SERVICE MEDFORD OR  
624 AM PDT SAT OCT 19 2024  
   
..CORRECTED MARINE DISCUSSION
 
 
   
AVIATION (12Z TAFS)
 
 
INLAND, CONFIDENCE IS HIGH FOR VFR CONDITIONS THROUGH THIS CYCLE.  
ALONG AND NEAR THE COAST IS MORE COMPLICATED AS BOTH LOW CLOUDS  
AND VISIBILITY RESTRICTIONS COULD DEVELOP TONIGHT LEADING TO  
IFR/LIFR CONDITIONS. THESE CHANCES (40-50%) ARE ANTICIPATED  
OVERNIGHT TONIGHT INTO SUNDAY MORNING FOR KOTH. OTHERWISE,  
INCREASING HIGH CLOUDS ALONG WITH LIGHT WIND SPEEDS ARE EXPECTED  
THROUGH THIS CYCLE.  
 
-GUERRERO  
 

 
   
PREV DISCUSSION
 
/ISSUED 342 AM PDT SAT OCT 19 2024/  
 
SHORT TERM...  
 
SOME HIGH LEVEL CLOUDS ARE PUSHING IN OVER THE FORECAST AREA THIS  
MORNING WITH TEMPERATURES TRENDING ABOUT 7 TO 10 DEGREES WARMER  
COMPARED TO 24 HOURS AGO. THAT THEME WILL CONTINUE INTO THE DAY AS  
TEMPERATURES END UP IN THE MID 70'S WEST OF THE CASCADES AND UPPER  
60'S EAST OF THE CASCADES. AN UPPER LEVEL RIDGE WILL STILL  
LINGER TO OUR SOUTH TODAY KEEPING THE WEATHER RATHER QUIET AHEAD  
OF THE NEXT SYSTEM SUNDAY  
 
AS FOR LATER TONIGHT, MODEL GUIDANCE IS SUGGESTING A 50% CHANCE  
FOR SOME PRECIPITATION ALONG THE COAST IN THE MARINE STRATUS.  
USUALLY THIS IS A PRETTY LIGHT DRIZZLE MIXED WITH PLENTY OF FOG.  
WE DECREASED THE PROBABILITY OF PRECIPITATION COMPARED TO THE  
GUIDANCE, ALTHOUGH CHANGED THE TERMINOLOGY TO DRIZZLE VERSUS RAIN  
IN THE FORECAST LATER TONIGHT INTO SUNDAY MORNING.  
 
BY SUNDAY, A COLD FRONT AND UPPER LEVEL WAVE WILL DESCEND ON  
SOUTHERN OREGON AND NORTHER CALIFORNIA. MOST OF THE WEATHER WILL  
OCCUR LATER IN THE DAY BASED ON WHEN THE FRONT MOVES ON SHORE  
BETWEEN 0Z AND 6Z MONDAY. THE CHANCE OF RAIN ALONG THE COAST IS  
100% AND BETWEEN 90 TO 70 PERCENT FOR LOCATIONS WEST OF THE  
CASCADES. GIVEN THE STRENGTH OF THE FRONT, MOST LOCATIONS WEST OF  
THE CASCADES SHOULD HAVE A GOOD CHANCE OF OBSERVING RAIN. THOSE  
PROBABILITIES DECREASE THE FARTHER ONE MOVES SOUTH.  
 
THE RAIN POTENTIAL WILL PERSIST INTO EARLY MONDAY WITH THE UPPER  
LEVEL WAVE TRAVERSING OREGON AND A COLD FRONT STALLING OUT AND  
BECOMING A WEAKENING STATIONARY FRONT. THEREFORE, ONE COULD SEE  
SOME LIGHT RAIN MONDAY AFTERNOON WITH SOME STRAY SHOWERS MOVING  
THROUGH.  
 
LONG TERM...  
 
THE EARLY PART OF THE EXTENDED FORECAST WILL START OUT FAIRLY  
QUIET FOR OUR AREA. MODELS ARE SUGGESTING AN ELONGATED UPPER LEVEL  
TROUGH WILL SPREAD OUT INTO THE PACIFIC EARLY IN THE FORECAST  
PERIOD. AN UPPER LEVEL JET AND BAROCLINIC ZONE WILL REMAIN  
SITUATED OVER OREGON BEFORE WE SEE SOME TYPE OF CYCLOGENESIS OUT  
AROUND 140W AND 40N. MODELS HAVE THIS LOW ARRIVING SOME TIME  
AROUND FRIDAY AND SATURDAY WITH VARYING INTENSITIES BASED ON THE  
ENSEMBLE MEMBERS ONE LOOKS AT. IT'S ALSO WORTH NOTING SOME  
MEMBERS(~5%) ARE COMPLETELY DRY AND ARE NOT SHOWING ANYTHING  
BETWEEN FRIDAY AND SATURDAY. OVERALL, IT LOOKS LIKE THE MOST  
LIKELY SOLUTION WILL BE A LOW WITH SOME STRENGTH WILL BRING MORE  
WETTING RAIN TO THE REGION BETWEEN FRIDAY AND SATURDAY. GIVEN THE  
SOUTHWEST TO NORTHEAST TRACK AND TIME OF YEAR, SNOWFALL DOESN'T  
APPEAR TO BE IN OUR FUTURE AS SNOW LEVELS REMAIN AROUND 8000  
FEET.  
 
-SMITH  
 
AVIATION...19/06Z TAFS...VFR WITH LIGHT, VARIABLE WINDS WILL  
PREVAIL OVER THE AREA FOR THE NEXT 24 HOURS. MID AND HIGH CLOUDS  
WILL DRIFT OVER MAINLY NORTHERN AND WESTERN SECTIONS AT TIMES. THESE  
CLOUDS WILL LOWER SOME TONIGHT ALONG THE COAST, PERHAPS TO MVFR AT  
NORTH BEND. ALSO, PATCHY FOG COULD REDEVELOP IN SOME TYPICAL WEST A  
SIDE VALLEY LOCATIONS, BUT PROBABLY NOT AT THE TERMINALS. -SPILDE  
 
MARINE (UPDATED 300 AM)...  
 
FOR TODAY, AN INCREASING WEST TO NORTHWEST SWELL WILL BRING ELEVATED  
SEAS AREA WIDE WITH STEEPENING WIND WAVES SOUTH OF CAPE BLANCO, BUT  
EXPECTING CONDITIONS TO REMAIN BELOW ADVISORY LEVELS. SOUTH WINDS  
INCREASE AHEAD OF A COLD FRONT TOMORROW, AND THIS COULD BRIEFLY  
BRING ISOLATED HAZARDOUS CONDITIONS DUE TO A COMBINATION OF STEEP  
WIND WAVES AND WESTERLY SWELL, MAINLY NORTH OF CAPE BLANCO. RAIN  
WILL ACCOMPANY THE FRONT THROUGH SUNDAY NIGHT, THEN MOVE ONSHORE  
WITH IMPROVING CONDITIONS MONDAY. THEN ADVISORY LEVEL CONDITIONS  
RETURN TUESDAY INTO MIDDLE AND LATER PARTS OF NEXT WEEK.  
 
-GUERRERO  
 

 
   
MFR WATCHES/WARNINGS/ADVISORIES
 
 
OR...NONE.  
 
CA...NONE.  
 
PACIFIC COASTAL WATERS...NONE.  
 

 
 

 
 
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