543
FXUS66 KMFR 170441
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
941 PM PDT TUE JUN 16 2026
..NEW AVIATION SECTION
AVIATION (06Z TAFS)
WHILE LOW CLOUDS EXIST ALONG THE COAST IMPACTING KOTH (IFR),
CONDITIONS SHOULD IMPROVE TONIGHT WITH VFR ANTICIPATED. IN FACT,
THE VAST MAJORITY OF THIS CYCLE WILL LIKELY BE VFR FOR ALL
TERMINALS. STILL A VERY SMALL CONCERN (10%) KRBG COULD SEE
LOW/MID CLOUDS LATER THIS MORNING, BUT CONFIDENCE WAS HIGHER TO
NOT INCLUDE THIS MENTION AT THIS TIME. OTHERWISE, EXPECTING A
BREEZY AFTERNOON ON WEDNESDAY WITH SPEEDS DIMINISHING AROUND
SUNSET.
-GUERRERO
PREV DISCUSSION
/ISSUED 430 PM PDT TUE JUN 16 2026/
.NEW AVIATION SECTION
AVIATION (00Z TAFS)...
ALONG/NEAR THE COAST WE HAVE A LAYER OF LOW CLOUDS IMPACTING KOTH
WITH IFR CONDITIONS POSSIBLE THROUGH THIS EVENING, BUT EXPECTING
SOME CLEARING OVERNIGHT WITH VFR CONDITIONS THEREAFTER. FARTHER
INLAND, WE HAVE VFR CONDITIONS WHICH WILL LIKELY PREVAIL
THROUGHOUT THE VALID TAF PERIOD. THERE IS SOME CONCERN FOR LOW/MID
LEVEL CLOUDS AROUND KRBG, BUT CONFIDENCE WAS TOO LOW (10% CHANCE)
TO INCLUDE AT THIS TIME. BREEZY AFTERNOON WIND SPEEDS EXPECTED
AGAIN TOMORROW AFTERNOON WITH SPEEDS DIMINISHING AROUND SUNSET
SIMILAR TO TODAY.
-GUERRERO
PREV DISCUSSION... /ISSUED 1254 PM PDT TUE JUN 16 2026/
DISCUSSION...IT IS ONCE AGAIN A BRIGHT, SUNNY, AND HOT DAY
ACROSS SOUTHERN OREGON AND FAR NORTHERN CALIFORNIA, ASIDE FROM
SOME MARINE LAYER STRATUS BEGINNING TO PUSH ITS WAY ONSHORE ALONG
AND NORTH OF CAPE BLANCO. THE HEAT WAVE WILL BEGIN TO EBB EVER SO
SLIGHTLY FOR AREAS WEST OF THE CASCADES TODAY, MOST NOTABLE ALONG
THE COAST NORTH OF CAPE BLANCO AND INTO THE UMPQUA BASIN. THE
UPPER LEVEL PATTERN RESPONSIBLE FOR THIS HEAT FEATURES A STRONG
HIGH PRESSURE JUST OFFSHORE OVER THE EASTERN PACIFIC, THAT WILL
WEAKEN AND EXPAND EASTWARD TODAY, EVENTUALLY SETTLING INTO THE
GREAT BASIN REGION BY THURSDAY. MEANWHILE, WEAK ENERGY WILL LINGER
OFF THE COAST OF CALIFORNIA AND MEANDER WESTWARD AROUND THIS HIGH
PRESSURE WHILE IT EXPANDS/SHIFTS EASTWARD. THIS ENERGY COMES INTO
PLAY FOR THE LATTER HALF OF THE WEEK. IN THE MEANTIME, A HEAT
ADVISORY REMAINS IN EFFECT THROUGH THIS EVENING DUE TO A MODERATE
RISK OF HEAT RELATED ILLNESSES. BE SURE TO TAKE PRECAUTIONS TO
PROTECT YOURSELF FROM THE HEAT. IF YOU PLAN TO SEEK RELIEF IN AREA
WATERWAYS, PLEASE REMEMBER THAT THE WATER IS STILL QUITE COLD,
AND COLD WATER SHOCK IS A REAL THING. TEMPERATURES DO TREND COOLER
FOR THE LATTER HALF OF THE WEEK, BUT WILL REMAIN ABOVE NORMAL
(MID-UPPER 90S WEST/UPPER 80S-LOW 90S EAST) UNTIL THE WEEKEND. SO
INSTEAD OF BEING 15-25 DEGREES ABOVE NORMAL LIKE YESTERDAY, IT'LL
"COOL" TO ONLY 10-15 DEGREES ABOVE NORMAL.
THE UPPER LEVEL PATTERN SHIFTS ON THURSDAY. THAT MEANDERING WEAK
ENERGY COMBINES WITH A FEW OTHER WEAK SHORTWAVES PASSING THROUGH IN
THE WESTERLIES AND CARVES OUT A WEAK OPEN TROUGH OVER THE EASTERN
PACIFIC BY THURSDAY AFTERNOON. TEMPERATURES TICK UPWARD A FEW
DEGREES ON THURSDAY UNDER SOUTHERLY FLOW, AND IT'S POSSIBLE WE SEE
ANOTHER TRIPLE DEGREE DAY HERE IN MEDFORD ON THURSDAY. THE LARGER
CONCERN HOWEVER, IS THE THUNDERSTORM POTENTIAL THAT COMES WITH THIS
PATTERN TRANSITION. IT'S ALMOST A GUARANTEE THAT HEAT WAVES CONCLUDE
WITH A THUNDER THREAT, AND IT SEEMS THIS EVENT IS NO DIFFERENT.
MOISTURE AND INSTABILITY INCREASE ON THURSDAY, AND THERE ARE SOME
WEAK SHORTWAVES PASSING THROUGH, BUT MOISTURE IS PRETTY MARGINAL ON
THURSDAY, AND FOCUSED MAINLY TO OUR SOUTH. IT'S MORE LIKELY THAT
THERE WILL BE SOME CUMULUS BUILDUPS WITH A STRAY SHOWER ACROSS
NORTHERN CALIFORNIA. BY FRIDAY, HOWEVER, THE TROUGH NUDGES CLOSER
AND MOISTURE LOOKS MORE FAVORABLE FOR THUNDERSTORMS. CURRENTLY, IT
LOOKS LIKE THE FOCUS WOULD BE ACROSS NORTHERN CALIFORNIA AND EAST
OF THE CASCADES, BUT MODEL GUIDANCE SHOWS SOME POTENTIAL
CONVECTION OVER THE SISKIYOUS, WHICH COULD BRING SOME STORMS INTO
SOUTHEASTERN JACKSON COUNTY. WE'LL KEEP AN EYE ON MODEL TRENDS TO
SEE IF THUNDERSTORM CHANCES EXPAND WESTWARD WITH TIME.
THE TROUGH AXIS MOVES THROUGH THE REGION FRIDAY NIGHT, TAKING THE
MOISTURE AND INSTABILITY EAST OF OUR REGION FOR SATURDAY. IT'S
POSSIBLE SOME ISOLATED ACTIVITY LINGERS ACROSS FAR EASTERN
LAKE/MODOC COUNTIES EARLY SATURDAY AFTERNOON. THE COOLEST
TEMPERATURES OF THE FORECAST PERIOD ARE EXPECTED OVER THE WEEKEND AS
THIS TROUGH PASSES THROUGH. AFTERNOON HIGHS WILL STILL BE ABOVE
NORMAL, BUT ONLY ON THE LEVEL OF 5-10 DEGREES.
AVIATION...16/18Z TAFS...GUSTY NORTH WINDS (20-30 KT) ARE RETURNING
TO THE COAST TODAY WHILE OTHER AREAS WILL SEE TYPICAL DIURNAL
BREEZES. VFR WILL CONTINUE IN MOST AREAS THROUGH THE TAF PERIOD
INLAND. PATCHES OF IFR STRATUS ARE POSSIBLE AT THE COAST NORTH OF
CAPE BLANCO THROUGH 21Z, WITH POTENTIALLY MORE COVERAGE TONIGHT.
MARINE...UPDATED 100 AM PDT TUESDAY, JUNE 16, 2026...A THERMAL
TROUGH PATTERN WILL STRENGTHEN TODAY AND PERSIST THROUGH THURSDAY.
CONDITIONS WILL WORSEN THIS AFTERNOON WITH NORTHERLY GALES SOUTH OF
CAPE BLANCO AND VERY STEEP SEAS SPREADING NORTH TO CAPE ARAGO BY
TONIGHT. CONDITIONS COULD IMPROVE LATE THURSDAY INTO FRIDAY AS THE
THERMAL TROUGH PATTERN WEAKENS, BUT STEEP SEAS AND MODERATE NORTH
WINDS ARE LIKELY TO PERSIST THROUGH THE WEEKEND.
FIRE WEATHER...UPDATED 100 PM PDT TUESDAY, JUNE 16, 2026...THE
HEATWAVE WILL BEGIN TO EBB TODAY FOR AREAS WEST OF THE CASCADES,
MOST NOTABLE ALONG THE COAST NORTH OF CAPE BLANCO AND INTO THE
UMPQUA BASIN. MEANWHILE, TEMPERATURES REMAIN HOT EAST OF THE
CASCADES AND ACROSS NORTHERN CALIFORNIA. WITH THE MODERATING
TEMPERATURES WEST OF THE CASCADES, CONDITIONS WILL BE LESS CRITICAL
TODAY, BUT IT WILL STILL BE DRY AND BREEZY THIS AFTERNOON.
A WEAK MARINE PUSH WILL BRING IMPROVING RECOVERIES TONIGHT COMPARED
TO RECENT DAYS, BUT THIS IMPROVEMENT WILL BE SHORTLIVED. THE THERMAL
TROUGH WILL REMAIN ALONG THE COAST THROUGH WEDNESDAY, THEN PUSH
INLAND ON THURSDAY. THIS WILL MAINTAIN BROAD NORTH THROUGH EAST FLOW
ACROSS THE MIDSLOPES/RIDGES, AND POOR RECOVERIES ARE EXPECTED AGAIN
WEDNESDAY NIGHT. AS THE THERMAL TROUGH SHIFTS INLAND THURSDAY,
EXPECT ANOTHER UPTICK IN TEMPERATURES ACROSS THE REGION.
ADDITIONALLY, THIS PATTERN WILL BRING DRY AND UNSTABLE CONDITIONS
ACROSS NORTHERN CALIFORNIA AND EAST OF THE CASCADES.
MEANWHILE, AN OPEN TROUGH DEVELOPS OFFSHORE OVER THE EASTERN PACIFIC
ON THURSDAY, MOVING INLAND LATE FRIDAY AND EAST OF THE REGION ON
SATURDAY. THIS PATTERN SETS UP THE POTENTIAL FOR THUNDERSTORMS
DURING THIS TIME FRAME, FOCUSED ACROSS NORTHERN CALIFORNIA AND EAST
OF THE CASCADES.
CHANCES FOR THUNDERSTORMS ARE HIGHEST ON FRIDAY, BUT COULD BEGIN AS
EARLY AS THURSDAY FOR SOUTHERN SISKIYOU AND MODOC COUNTIES. MOISTURE
REMAINS FAIRLY MARGINAL FOR THURSDAY, BUT INSTABILITY IS PRESENT.
COULD JUST BE SOME CUMULUS BUILDUPS WITH A STRAY SHOWER OR EVEN AN
ISOLATED THUNDERSTORM IN THE AFTERNOON. AS THE UPPER LEVEL LOW MOVES
CLOSER TO THE COAST ON FRIDAY, THE CHANCE OF SHOWERS AND
THUNDERSTORMS INCREASES. CURRENT GUIDANCE MAINTAINS THE BEST CHANCES
ACROSS NORTHERN CALIFORNIA AND EAST OF THE CASCADES, BUT THERE IS
THE POTENTIAL FOR AS FAR WEST AS JOSEPHINE COUNTY. BY SATURDAY, THE
BEST MOISTURE/INSTABILITY SHIFTS EAST, LEAVING SOME LINGERING
CHANCES ALONG/EAST OF THE WARNERS/WINTER RIDGE.
MFR WATCHES/WARNINGS/ADVISORIES
OR...CA...NONE.
PACIFIC COASTAL WATERS...GALE WARNING UNTIL 8 PM PDT THURSDAY FOR
PZZ356-376.
SMALL CRAFT ADVISORY UNTIL 8 PM PDT THURSDAY FOR PZZ350-370.
HAZARDOUS SEAS WARNING UNTIL 8 PM PDT THURSDAY FOR PZZ350-370.
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