807
FXUS66 KMFR 041730
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
1030 AM PDT THU JUN 4 2026
..NEW AVIATION SECTION
AVIATION (18Z TAFS)
SATELLITE IMAGERY INDICATES LOW CLOUDS OVER THE UMPQUA BASIN WHICH
IS IMPACTING KRBG WITH MVFR CEILINGS. EXPECTING THIS DECK TO
CLEAR OUT WITH AFTERNOON MIXING. THEREAFTER, THIS SHOULD BE
MOSTLY A VFR TAF CYCLE AS THE AFTERNOON BRINGS DECENT MIXING AND
BREEZY WIND SPEEDS TODAY. THESE WILL BE DIURNALLY DRIVEN WITH
SPEEDS DIMINISHING AROUND SUNSET. EXPECTING A MARINE LAYER TONIGHT
THAT COULD BRING MVFR CONDITIONS (~40%) ALONG/NEAR THE COAST
IMPACTING KOTH.
-GUERRERO
PREV DISCUSSION
/ISSUED 609 AM PDT THU JUN 4 2026/
.UPDATED AVIATION DISCUSSION FOR 12Z TAFS
DISCUSSION...BREEZY WINDS HAVE GENERALLY EASED EARLY THIS MORNING
AS A WEAK FRONT CONTINUES EASTWARD. MERLIN HAD THE HIGHEST OBSERVED
RAINFALL AMOUNT THROUGH WEDNESDAY, WITH 0.04 INCHES MEASURED.
FOR TODAY AND FRIDAY, ZONAL FLOW ALOFT WITH SOME HINTS OF SLIGHT
RIDGING WILL KEEP DAYTIME HIGHS WITHIN 5 DEGREES OF SEASONAL NORMS
ACROSS THE AREA. CLOUD COVER INCREASES ON FRIDAY AFTERNOON AS A LOW
PRESSURE SYSTEM APPROACHES WASHINGTON STATE. THIS PASSING LOW LOOKS
TO BE GENERALLY UNEVENTFUL. DAYTIME TEMPERATURES COOL ON SATURDAY
BEFORE RETURNING TO NEAR SEASONAL AVERAGES ON SUNDAY. NORTHERN LAKE
AND KLAMATH COUNTIES MAY SEE LOWS REACH FREEZING LEVELS EARLY
SATURDAY MORNING AND EARLY SUNDAY MORNING. BREEZY WINDS ARE EXPECTED
FRIDAY AFTERNOON THROUGH SATURDAY AFTERNOON. GUSTY NORTHERLY WINDS
MAY DEVELOP ON SATURDAY EVENING AND NIGHT AS ENERGY SWIRLING AROUND
THE LOW NUDGES THE TROUGH CLOSER TO THE AREA, TIGHTENING PRESSURE
GRADIENTS. THESE WINDS WILL BE HIGHEST IN THE SHASTA VALLEY AND OVER
EAST SIDE TERRAIN BUT LOOK SAFELY SHORT OF ADVISORY LEVEL SPEEDS.
PRECIPITATION WITH THIS SYSTEM IS A NON-ISSUE, AS ONLY NORTHERNMOST
COOS AND DOUGLAS COUNTIES HAVE 10% CHANCES TO SEE ANY RAINFALL.
THE TROUGH MOVES TO THE EAST SUNDAY MORNING, ONLY TO BE FOLLOWED BY
ANOTHER LOW PRESSURE SYSTEM APPROACHING LATER IN THE DAY. THIS
SECOND LOW IS EXPECTED TO MOVE OVER THE AREA, BRINGING COOLER
TEMPERATURES ACROSS THE AREA. THE OREGON COAST AND CASCADES WILL SEE
SHOWERS THROUGH MONDAY AND TUESDAY, WITH SLIGHT CHANCES FOR RAINFALL
OVER WEST SIDE VALLEYS. CURRENTLY, AREAS EAST OF THE CASCADES ARE
EXPECTED TO STAY DRY. THUNDERSTORM ACTIVITY IS DIFFICULT TO FORECAST
THIS FAR OUT, BUT GFS DETERMINISTIC IMAGERY IS SHOWING SOME CAPE
BRING PRESENT WEST OF THE CASCADES ON MONDAY AFTERNOON AND TUESDAY
AFTERNOON.
BEHIND THE SECOND LOW, LOMG-TERM IMAGERY SHOWS AN UPPER RIDGE
DEVELOPING OVER THE PACIFIC OCEAN AND POSSIBLY EXTENDING OVER THE
AREA. THERE'S SOME DISAGREEMENT IN PLACEMENT AND DEPTH, BUT NEXT
WEEK COULD END WITH WARM AND DRY CONDITIONS. -TAD
AVIATION...04/12Z TAFS...AREAS OF IFR TO LIFR CEILINGS REMAIN IN
SOME AREAS OF THE OREGON COAST, BUT LOCAL TERMINALS AND INLAND AREAS
ARE STARTING THE DAY AT VFR LEVELS. THESE LEVELS WILL BE PRESENT
MUCH OF THE DAY, WITH ONLY SOME GUSTY WINDS ALONG THE COAST IN THE
AFTERNOON TO NOTE.
A LOW PRESSURE SYSTEM PASSING TO THE NORTH WILL BRING SOME CLOUD
COVER TO THE COAST AND INTO THE UMPQUA VALLEY TOWARDS THE END OF THE
TAF PERIOD. MVFR CEILINGS ARE POSSIBLE, WITH HIGHER CHANCES FOR
COASTAL AREAS. INLAND AREAS WILL REMAIN AT VFR LEVELS THROUGH THE
TAF PERIOD. -TAD
MARINE...UPDATED 200 AM PDT THURSDAY, JUNE 4, 2026...NORTHERLY
WINDS AND STEEP SEAS ARE BUILDING STEEP SEAS SOUTH OF CAPE BLANCO
INTO EARLY FRIDAY MORNING. CONDITIONS EASE BEFORE FRIDAY AFTERNOON,
BUT INCREASED NORTH WINDS AND STEEP WIND DRIVEN SEAS ARE FORECAST
TO RETURN LATE SATURDAY INTO SUNDAY, AND AGAIN EARLY MONDAY INTO
TUESDAY.
MFR WATCHES/WARNINGS/ADVISORIES
OR...CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 8 AM PDT FRIDAY
FOR PZZ356-376.
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