293  
FXUS66 KMFR 060218  
AFDMFR  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MEDFORD OR  
718 PM PDT SUN APR 5 2026  
   
..UPDATED THE AVIATION AND MARINE SECTIONS  
 
   
AVIATION...06/00Z TAFS  
VFR CONDITIONS WILL PERSIST THROUGH  
MONDAY NIGHT FOR MOST THE AREA. THE EXCEPTION WILL BE AREAS OF  
LIFR/IFR CEILINGS AND VISIBILITIES ALONG THE COAST, INCLUDING NORTH  
BEND (KOTH), FROM AROUND 03Z THIS EVENING THROUGH 18Z MONDAY  
MORNING, AS WEAK ONSHORE FLOW DEVLOPS.  
 
 
   
MARINE...UPDATED 715 PM PDT SUNDAY, APRIL 5, 2026  
RELATIVELY  
CALM CONDITIONS ARE EXPECTED THROUGH MONDAY NIGHT. A THERMAL TROUGH  
WILL DEVELOP ON TUESDAY WITH INCREASING NORTH WINDS INTO WEDNESDAY.  
WINDS WILL BE STRONGEST SOUTH OF CAPE BLANCO, BUT STEEP SEAS ARE  
LIKELY FOR ALL OF THE WATERS BEGINNING ON TUESDAY AFTERNOON.  
 
A TROUGH IS EXPECTED TO REMAIN SOUTH OF THE WATERS ON THURSDAY AND  
MOVE ACROSS CALIFORNIA FROM FRIDAY THROUGH THE WEEKEND. THIS WILL  
CONTINUE THE MODERATELY INTENSE PATTERN OF LOW PRESSURE INLAND AND  
HIGH PRESSURE OFFSHORE WITH SEAS LIKELY TO REMAIN STEEP WHILE NORTH  
WINDS REMAIN NEAR OR AT SMALL CRAFT ADVISORY STRENGTH.  
 
 
   
PREV DISCUSSION  
/ISSUED 1235 PM PDT SUN APR 5 2026/  
 
DISCUSSION...  
 
HIGH CLOUDS CONTINUE TO MOVE THROUGH THE REGION THIS AFTERNOON.  
HOWEVER, PLENTY OF SUN IS STILL FILTERING THROUGH THOSE HIGHER  
CLOUDS AND WE'RE ANTICIPATED TO WARM UP INTO THE LOWER 70'S AGAIN  
TODAY. A THERMAL TROUGH IS ALONG THE CASCADES AND THAT TROUGH  
WILL RETREAT FARTHER TO THE EAST DURING THE AFTERNOON HOURS.  
OVERALL, NOT MUCH GOING ON EXCEPT FOR THE ABOVE NORMAL  
TEMPERATURES TODAY.  
 
THE FLOW PATTERN WILL BECOME MORE ONSHORE BY TOMORROW, ALTHOUGH  
TEMPERATURES WILL REMAIN WARM IN THE VALLEYS WITH MORE UPPER 70'S  
WEST OF THE CASCADES AND LOWER 70'S EAST OF THE CASCADES. THE  
VERY LOW(10-20%) CHANCE OF THUNDERSTORMS PERSIST ON MONDAY.  
LOOKING AT SOUNDINGS THE AMOUNT OF CONVECTIVE AVAILABLE POTENTIAL  
ENERGY(CAPE) IS LOW AND ONLY 100-200 J/KG. THE SPC HREF  
CALIBRATED THUNDER ALGORITHM IS GOING WITH A 10-20% CHANCE, SO  
FELT THAT WAS FAIR. DON'T BE SURPRISED IF NOTHING HAPPENS AND WE  
JUST GET SOME SHOWERS ALONG AND EAST OF THE CASCADES MONDAY  
AFTERNOON AND EVENING.  
 
BY TUESDAY MORNING, AN UPPER LEVEL TROUGH IN CANADA STARTS TO DIG  
DOWN INTO WASHINGTON AND IDAHO WITH A CUT OFF LOW OFF THE COAST OF  
NORTHERN CALIFORNIA. IN ADDITION, A COLD FRONT SHOULD BE MOVING  
SOUTH DURING THE DAY AS WELL. THIS FRONT STALLS OUT OVER CENTRAL  
OREGON DURING THE DAY WITH HIGHS IN THE MID 70'S IN SOUTHERN  
OREGON AND MID 60'S FARTHER NORTH OF EUGENE AND BEND. THE FORECAST  
HAS ALSO TRENDED DRIER COMPARED TO YESTERDAY WITH A 5-10% CHANCE  
OF RAIN DURING THE DAY. IT SEEMS 500 MB HEIGHTS ARE AMPLIFYING  
AHEAD OF THE CUT OFF LOW, SO THAT CUTS OFF MOISTURE AND ENHANCES  
THE SINKING MOTION.  
 
AS THAT DEEPER TROUGH DIGS FURTHER INTO THE CONUS, THE CUTOFF LOW  
REMAINS OFF OUR COAST BY WEDNESDAY. THE CHANCE OF RAIN IS ABOUT 20  
TO 30 PERCENT OVER OUR FORECAST AREA, ALTHOUGH THAT COULD VERY  
WELL TREND LOWER DEPENDING ON HOW THIS UPPER LEVEL LOW BEHAVES.  
MOST ENSEMBLE MEMBERS ALSO SEEM TO BE TARGETING NORTHERN  
CALIFORNIA, SO THE PROBABILITY FOR PRECIPITATION IS HIGHER THERE  
COMPARED TO PARTS OF OREGON.  
 
THIS CUTOFF LOW BEGINS TO TRAVEL SOUTH ALONG THE CALIFORNIA  
COASTLINE WITH SOME STRONG 500 MB DIVERGENCE OVER OUR FORECAST  
AREA ON THURSDAY. THIS SHOULD RESULT IN SHOWERS AND PERHAPS MORE  
THUNDERSTORMS DEPENDING ON CAPE. HOWEVER, THE POP FORECAST  
SUGGESTS A WET DAY WITH A 50-60% CHANCE OF RAIN THURSDAY MORNING  
AND AFTERNOON.  
 
THE EXTENDED FORECAST IS LOOKING WET AROUND FRIDAY INTO NEXT WEEK  
WITH THE VAST MAJORITY OF ENSEMBLE MEMBERS WITH PRECIPITATION IN  
THE FORECAST.  
 
-SMITH  
 
 
   
MFR WATCHES/WARNINGS/ADVISORIES  
 
OR...NONE.  
 
CA...NONE.  
 
PACIFIC COASTAL WATERS...NONE.  
 
 
 
 
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