883
FXUS66 KMFR 151751
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
1051 AM PDT FRI AUG 15 2025
..UPDATED AVIATION DISCUSSION FOR 18Z TAFS
DISCUSSION
SATELLITE IMAGE SHOWS HIGH AND MID LEVEL CLOUDS
AHEAD OF A FRONT THAT IS NORTHWEST OF THE AREA. A COLD FRONT WILL
SLOWLY MOVE SOUTH INTO THE NORTHWEST PART OF THE AREA TODAY. MOST
LIKELY SCENARIO WILL BE INTERMITTENT LIGHT RAIN IN COOS, NORTHWEST
DOUGLAS COUNTY, AND NORTHERN CASCADES THIS AFTERNOON. EVEN THEN
PRECIP AMOUNTS MAY ONLY END UP BRING 0.01-0.05 OF AN INCH.
THE UPPER TROUGH WILL DEEPEN TONIGHT INTO SATURDAY MORNING WHICH
WILL ALLOW THE FRONT TO MOVE SOUTH. THE BEST CHANCE FOR
PRECIPITATION WILL BE ALONG THE COAST, COASTAL MOUNTAINS, NORTH
OFTHE UMPQUA DIVIDE, AND NORTHERN CASCADES. THE NBM SOLUTION IS
ONCE AGAIN TOO FAR SOUTH AND INLAND WITH THE EXTENT OF THE
PRECIPITATION AND THE FORECAST HAS BEEN ADJUSTED TO KEEP THE BEST
CHANCE OF RAIN TO THE ABOVE MENTIONED AREAS.
SATURDAY AFTERNOON, THE FRONT WILL MOVE INLAND AND PRECIPITATION
WILL BECOME SHOWERY IN THAT IT WILL BE CONVECTIVE IN NATURE.
GUIDANCE SHOWS INSTABILITY WILL BE MARGINAL AT BEST IN THE
NORTHERN CASCADES, AND NORTHERN KLAMATH AND LAKE COUNTY AND HAVE A
SLIGHT CHANCE OF THUNDERSTORMS CONFINED TO THESE AREAS. MEANWHILE,
CONVECTIVE SHOWERS ARE POSSIBLE ALONG AND WEST OF THE CASCADES.
SUNDAY INTO EARLY NEXT WEEK, THE PARENT UPPER LOW FROM THE GULF OF
ALASKA WILL REMAIN PARKED JUST SOUTH OF THE ALASKA PANHANDLE WITH
A BROAD SOUTHWEST FLOW ALOFT OVER OUR AREA. INSTABILITY SUNDAY
AFTERNOON IS MARGINAL ALONG WITH WEAK SHORTWAVES MOVING THROUGH,
THEREFORE ISOLATED STORMS ARE POSSIBLE AGAIN FOR PORTIONS OF THE
EASTSIDE AND PORTIONS OF MODOC AND EASTERN SISKIYOU COUNTY.
DRY WEATHER IS LIKELY NEXT WEEK. UPPER TROUGHING REMAINS FOR THE
FIRST PART OF NEXT WEEK WITH TEMPERATURES NEAR SEASONAL NORMS. THE
OPERATIONAL MODELS, CLUSTERS AND ENSEMBLES ALL POINT TOWARDS A
FOUR CORNERS HIGH STRENGTHENING WITH A PORTION OF THE RIDGE NUDGING
TOWARDS THE FORECAST AREA MID TO LATE NEXT WEEK WITH ABOVE NORMAL
TEMPERATURES FOR THE INTERIOR. HIGHS WILL BE IN THE MID TO UPPER 90S
FOR THE INTERIOR WESTSIDE VALLEYS AND LOWER 90S EAST OF THE
CASCADES. -PETRUCELLI
AVIATION...15/18Z TAFS
IFR CONDITIONS CONTINUE ALONG THE OREGON
COAST, WHILE CLOUDS ARE MOVING INLAND AHEAD OF AN APPROACHING FRONT.
INLAND CEILINGS LOOK TO REMAIN AT VFR LEVELS, WHILE MVFR TO IFR
CEILINGS ARE EXPECTED FOR COASTAL AREAS. COASTAL SHOWERS ARE
EXPECTED TO START THIS AFTERNOON OR EARLY THIS EVENING, WITH
ACTIVITY MOVING INLAND BUT DECREASING AS THE FRONT MOVES EASTWARD.
PASSING RAIN SHOWERS MAY LOCALLY LOWER CEILINGS AND VISIBILITIES AS
WELL AS OBSCURE ELEVATED TERRAIN. -TAD
MARINE...UPDATED 200 AM PDT FRIDAY, AUGUST 15, 2025
RELATIVELY
CALMER CONDITIONS CALMER ARE EXPECTED THROUGH THE WEEKEND. A FRONT
MOVING INTO THE REGION WILL BRING PERIODS OF RAIN LATE FRIDAY INTO
SATURDAY WITH BUILDING WEST-NORTHWEST SWELL. SEAS WILL PEAK THIS
WEEKEND, BUT PROBABLY REMAIN JUST BELOW ADVISORY LEVELS. SEAS LOWER
SUNDAY NIGHT INTO MONDAY.
FIRE WEATHER
UPDATED 200 AM PDT FRIDAY, AUGUST 15,
2025...A COOLING TREND WILL CONTINUE THROUGH THE WEEKEND AS THE
UPPER RIDGE RETREATS AND GETS REPLACED WITH UPPER TROUGHING.
AN UPPER LOW FROM THE GULF OF ALASKA WILL DROP SOUTH TOWARD WESTERN
B.C. IN THE GULF OF ALASKA TODAY. THE LEADING EDGE OF A COLD FRONT
WILL APPROACH THE AREA DURING THE DAY FRIDAY AND WILL BRING
INTERMITTENT LIGHT RAIN TO PORTIONS OF FIRE ZONES 615 AND NORTHWEST
616.
THE FRONT WILL CONTINUE TO MOVE SOUTH TONIGHT INTO SATURDAY MORNING
AND COULD INCREASE THE CHANCE OF VERY LIGHT RAIN TO THE REST OF THE
COAST, COASTAL MOUNTAINS AND DOUGLAS COUNTY.
SATURDAY, THE FRONT WILL MOVE FARTHER INLAND WITH CONVECTIVE SHOWERS
PUSHING INLAND. GUIDANCE SUGGEST MARGINAL INSTABILITY SATURDAY
AFTERNOON. THIS ALONG WITH COOLER AIR ALOFT MOVING OVERHEAD, DAYTIME
HEATING AND TRIGGER WILL BE SUFFICIENT ENOUGH FOR ISOLATED
THUNDERSTORMS TO DEVELOP IN THE AFTERNOON INTO THE EARLY EVENING
HOURS SATURDAY ALONG AND EAST OF THE CASCADES AND NORTHERN
CALIFORNIA. THUNDERSTORMS ARE ALSO EXPECTED TO BRING RAINFALL.
SUNDAY, A BROAD UPPER LOW WILL SET UP NORTH OF THE AREA WITH A
SOUTHWESTERLY FLOW ALOFT. MOST OF THE INSTABILITY IS EXPECTED TO BE
IN PORTIONS OF FIRE ZONES 624, 625, 285 AND NORTHEAST 284 LATE IN THE
AFTERNOON, THEN SHIFTING INTO JUST PORTIONS OF FIRE ZONE 625 EARLY
SUNDAY EVENING.
UPPER TROUGHING REMAINS IN PLACE EARLY NEXT WEEK, BUT IT EXPECTED TO
REMAIN DRY WITH TEMPERATURES NEAR SEASONAL NORMS, THEN THERE ARE
SIGNS OF UPPER RIDGING BUILDING BACK TOWARDS THE AREA, WITH
TEMPERATURES GETTING ABOVE NORMAL, BUT IT WON'T BE HOT. -PETRUCELLI
MFR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
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