968
FXUS66 KMFR 222014
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
114 PM PDT WED JUL 22 2026
KEY MESSAGES
* TODAY WILL BE LAST DAY OF THE HUMID PATTERN WITH MOIST, SOUTHERLY
MONSOONAL FLOW AND ISOLATED TO SCATTERED THUNDERSTORMS. HIGHEST
RISK OF SCATTERED THUNDERSTORMS TODAY WILL BE FROM THE CASCADE
FOOTHILLS IN EASTERN DOUGLAS COUNTY ACROSS THE CASCADES, INTO
NORTHERN KLAMATH AND LAKE COUNTIES. SOME STORMS WILL BE STRONG
WITH GUSTY WINDS AND POSSIBLE HAIL.
* TODAY WILL BE THE HOTTEST DAY OF THE NEXT SEVERAL DAYS WITH HIGHS
GENERALLY 5 TO 10 DEGREES ABOVE NORMAL (MID 80S TO MID 90S ON THE
EAST SIDE AND LOWER 90S TO 104 FOR WEST SIDE VALLEYS). NEAR OR
SLIGHTLY BELOW NORMAL TEMPERATURES AT THE COAST WILL REACH THE
60S.
* A DRY PATTERN TAKES HOLD THURSDAY INTO THE WEEKEND. AN INCREASE
IN AFTERNOON/EVENING SOUTHWEST TO WEST WINDS IS LIKELY,
ESPECIALLY EAST OF THE CASCADES AND IN NE CALIFORNIA WHERE
STRONG WINDS OVERLAP WITH VERY LOW HUMIDITY RESULTING IN
CRITICAL FIRE WEATHER CONDITIONS FRIDAY AND SATURDAY.
DISCUSSION
THE AREA HAS BEEN WEDGED BETWEEN STRONG UPPER
RIDGING OVER THE NATION'S MIDSECTION AND LOW PRESSURE OFF THE
WEST COAST FOR THE LAST SEVERAL DAYS, WHICH HAS BROUGHT A PLUME OF
VERY MOIST, MONSOONAL MOISTURE INTO THE AREA. WITH DEWPOINTS
EXPECTED TO BE IN THE UPPER 50S TO EVEN MID 60S WEST OF THE
CASCADES, IT'LL BE ANOTHER HUMID DAY WITH HIGH TEMPERATURES AGAIN
IN THE 90S AND EVEN LOWER 100S TODAY. IN THIS TYPE OF PATTERN, WE
USUALLY EXPECT DAILY OUTBREAKS OF THUNDERSTORMS. BUT, THIS HAS
BEEN MUTED SO FAR WITH JUST ISOLATED ACTIVITY, MAINLY DUE TO A
LACK OF FORCING AND HIGH CLOUD COVER ULTIMATELY REDUCING
INSTABILITY. THIS WILL CHANGE SOMEWHAT TODAY AS INSTABILITY
INCREASES ACROSS THE AREA AND WITH THE LOW OFFSHORE MOVING
NORTHWARD (ALONG WITH THE REMNANTS OF ELIDA), FORCING FOR ASCENT
SHOULD BE ENHANCED NEAR THE CASCADES IN DIFFLUENT FLOW ALOFT. IT
WILL BE A RACE THOUGH, SO TO SPEAK, SINCE MODELS ARE SHOWING DRIER
AIR ALOFT ARRIVING FROM THE SOUTH AND WEST TODAY AND TONIGHT.
THE FOCUS FOR CONVECTION THIS AFTERNOON/EVENING WILL BE FROM THE
CASCADE FOOTHILLS OF EASTERN DOUGLAS COUNTY ACROSS THE CASCADES TO
NORTHERN KLAMATH AND LAKE COUNTIES. CONVECTION ALLOWING MODELS SHOW
THIS AREA STANDS A GOOD CHANCE AT GETTING SOME CELLS WITH FREQUENT
LIGHTNING. THEY'LL MOVE QUICKLY, AROUND 20-25 MPH TO THE NNE, AND
WITH A VERY DRY LANDSCAPE, THIS PRESENTS A CRITICAL FIRE WEATHER
RISK, SO WE HAVE A RED FLAG WARNING OUT FOR THAT. STORMS THAT DO
DEVELOP COULD ALSO HAVE STRONG OUTFLOW WIND GUSTS (INVERTED-V
SOUNDINGS INDICATE POTENTIAL NEAR OR JUST SUB-SEVERE GUSTS), HAIL
AND BRIEF HEAVY RAINFALL. THE STORM PREDICTION CENTER (SPC) DOES
HAVE PORTIONS OF OUR REGION IN A MARGINAL RISK FOR SEVERE WEATHER
TODAY, MEANING THERE'S A 2%-5% CHANCE FOR ANY STORM TO BECOME SEVERE
WITHIN 25 MILES OF ANY LOCATION WITHIN THE DESIGNATED AREA. THE
HIGHLIGHTED AREA IS MAINLY FROM CRATER LAKE NORTHWARD ALONG THE
CASCADES AND EASTWARD ACROSS NORTHERN KLAMATH/LAKE COUNTIES. WHILE
WE CAN'T RULE OUT ISOLATED ACTIVITY FARTHER SOUTH AND WEST, AGAIN,
THE LIMITING FACTOR WILL BE THE DRIER AIR MOVING IN ALOFT. EXPECT
SOME BREEZY WINDS TO DEVELOP JUST ABOUT EVERYWHERE THIS
AFTERNOON/EVENING.
ONCE WE GET RID OF THE CONVECTION THIS EVENING, THAT WILL BE IT FOR
A WHILE. A RE-ORIENTATION OF THE FLOW ALOFT TO THE SOUTHWEST WILL
BRING IN A MUCH DRIER PATTERN. MODELS ARE SHOWING A STRONG MID-LEVEL
500 MB JET OF 45-55 KT DEVELOPING FRI/SAT. THIS IS GOING TO CAUSE
BREEZY TO WINDY CONDITIONS AREA WIDE, STRONGEST EAST OF THE CASCADES
AND IN NE CALIFORNIA. AT THE SAME TIME, MASSIVE DRYING WILL BRING
DEWPOINTS WAY DOWN RESULTING IN VERY LOW HUMIDITY, IN SOME CASES,
DOWN BELOW 10% OVER MODOC/LAKE COUNTIES. THERE IS HIGH CONFIDENCE IN
THIS PATTERN OF OVERLAPPING STRONG, GUSTY WINDS AND LOW RELATIVE
HUMIDITY, AND A FIRE WEATHER WATCH IS IN PLACE FOR BOTH FRI/SAT
PM/EVE EAST OF THE CASCADES AND IN NE CALIFORNIA. THESE CONDITIONS
COULD PERSIST INTO SUNDAY, BUT CONFIDENCE WAS NOT HIGH ENOUGH TO
INCLUDE SUNDAY IN THE WATCH AT THIS TIME. TEMPERATURES, MEANWHILE,
SHOULD MODERATE A BIT THURSDAY AND FRIDAY, COOLING BY ABOUT 5 TO 10
DEGREES WEST OF THE CASCADES. TEMPERATURES WILL EVEN RETURN TO NEAR
TO JUST BELOW SEASONAL NORMALS BY THE END OF THE WEEKEND AND INTO
EARLY NEXT WEEK. MONSOONAL MOISTURE SHOULD REMAIN WELL TO THE SOUTH
AND EAST OF OUR AREA INTO NEXT WEEK DUE TO PERSISTENT SOUTHWEST FLOW
ALOFT, WHICH IS PRETTY TYPICAL FOR LATE JULY.
AVIATION...22/18Z TAFS
MOSTLY VFR IS PRESENT ACROSS NORTHERN
CALIFORNIA AND SOUTHERN OREGON EARLY THIS MORNING.
MARINE STRATUS HAS BURNED BACK FROM MOST OF THE COAST, BUT REMAINS
PRESENT IN THE OFFSHORE WATERS. WE EXPECT ONSHORE FLOW TO COMMENCE
AS THE DAY GOES ON, SO IT IS POSSIBLE THAT A SURGE OF LOW STRATUS
COULD RESULT IN IFR THERE THIS AFTERNOON. A STRONGER MARINE PUSH
TONIGHT WILL RESULT IN IFR CONDITIONS ALONG THE COAST AND INTO THE
UMPQUA BASIN OVERNIGHT TONIGHT.
THUNDERSTORMS ARE EXPECTED THIS AFTERNOON, ESPECIALLY OVER
EASTERN DOUGLAS COUNTY AS WELL AS LAKE AND NORTHERN KLAMATH
COUNTIES. ACTIVITY MAY ALSO DEVELOP IN JACKSON, AND SOUTHERN
KLAMATH, AND WESTERN SISKIYOU COUNTIES. THESE STORMS MAY BE STRONG
ENOUGH TO DEVELOP SMALL HAIL, LIGHTNING, LOCALLY HEAVY RAIN, AND
GUSTY, ERRATIC WINDS. WHILE THE MOST AGGRESSIVE ACTIVITY IS
CURRENTLY EXPECTED TO MOSTLY STAY AWAY FROM AREA TERMINALS, NOTES
OF VICINITY ACTIVITY HAVE BEEN INCLUDED AT MEDFORD TO COMMUNICATE
THE POSSIBLE DEVELOPMENT OF THUNDERSTORM ACTIVITY. -SPILDE/BPN
MARINE...UPDATED 100 PM PDT WEDNESDAY, JULY 22, 2026
AS TROPICAL
REMAINS MOVE NORTH THROUGH THE SOUTHERN OREGON COASTAL WATERS
TONIGHT INTO EARLY THURSDAY MORNING, THERE WILL BE A BRIEF PERIOD OF
STRONGER SOUTH WINDS AND STEEP SEAS, MAINLY IN WATERS BEYOND 10 NM
FROM SHORE. OTHERWISE, MIXED SEAS WITH FRESH SHORT PERIOD NORTHWEST
SWELL AND LOW LONGER PERIOD SOUTH SWELL ARE EXPECTED THROUGH FRIDAY.
SOUTH WINDS SWITCH BACK TO NORTHERLY THIS WEEKEND, BUT WIND WAVE
DOMINATED SEAS PROBABLY HOLD OFF UNTIL EARLY NEXT WEEK.
-SPILDE/BPN
FIRE WEATHER...UPDATED 100 PM PDT WEDNESDAY, JULY 22, 2026
TODAY, THERE IS A GREATER CONCERN FOR INCREASED AFTERNOON AND
EVENING THUNDERSTORM COVERAGE (AT LEAST IN NORTHERN PARTS OF THE
AREA) DUE TO BETTER INSTABILITY EXPECTED AND THE POTENTIAL FOR
BETTER FORCING AS THE REMNANTS OF ELIDA PUSH NORTHWARD JUST OFFSHORE
RESULTING IN DIFFLUENT FLOW ALOFT. WE THINK THE GREATEST ACTIVITY IN
TERMS OF COVERAGE WILL OCCUR ALONG THE WESTERN SLOPES OF THE
CASCADES (EASTERN FWZS 622/617) EAST ACROSS THE CASCADES (FWZ623),
AND THEN ALSO EAST OF THE CASCADES IN THE TYPICAL ARC FROM CRATER
LAKE, ACROSS WINTER RIM, AND DOWN TO THE WARNERS (FWZS 624/625).
ISOLATED STORMS ARE ALSO POSSIBLE ELSEWHERE ACROSS THE AREA,
INCLUDING IN NORTHERN CALIFORNIA AND ACROSS THE VALLEYS
WEST OF THE CASCADES, THOUGH A SURGE OF DRIER AIR ALOFT DOES APPEAR
TO BE PUSHING INTO NORCAL LATER IN THE AFTERNOON/EVENING (THIS
SHOULD KEEP BEST ACTIVITY CONFINED TO AREAS NORTH OF THE OR/CA
BORDER). STORMS THAT DO DEVELOP SHOULD BE MOVING AT A PRETTY GOOD
CLIP - IN THE 20-30 MPH RANGE, SO WHILE THEY ARE LIKELY TO BE WETTER
STORMS WITH HIGHER PWS, THE FASTER STORM MOTIONS STILL RAISES THE
RISK OF LIGHTNING-INDUCED FIRE IGNITIONS AND A RED FLAG WARNING IS
IN EFFECT.
OF NOTE, WITH PW APPROACHING OR EXCEEDING 1.50 INCHES, OR ROUGHLY
200 PERCENT OF NORMAL, THESE STORMS SHOULD NOT ONLY BE WET, BUT
COULD PRODUCE HEAVY RAIN AS WELL. SHOULD A STORM PASS DIRECTLY OVER
A RECENT BURN, SUCH AS THE EAST EVANS CREEK FIRE, MUD AND DEBRIS
FLOWS ARE POSSIBLE DOWN ANY ADJACENT DRAINAGES.
LATER THIS WEEK (THURSDAY/FRIDAY), EASTWARD MOVEMENT IN THE UPPER
LEVEL PATTERN IS LIKELY, WHICH IS LIKELY TO SHIFT THE REGION OF
INSTABILITY EAST OF OUR AREA WITH DRIER SW FLOW ALOFT WINNING OUT.
AS SUCH, LIGHTNING RISK WILL DIMINISH TO ALMOST NIL BY THURSDAY, BUT
AT THE EXPENSE OF ENHANCED SOUTHWEST TO WESTERLY WINDS DURING THE
AFTERNOONS AND EVENINGS EAST OF THE CASCADES, WHICH COULD OVERLAP
WITH LOW HUMIDITY, ESPECIALLY ON FRIDAY AND SATURDAY. ANY NEW FIRE
STARTS WOULD THEN HAVE THE ABILITY TO SPREAD/GROW QUICKLY. A FIRE
WEATHER WATCH IS IN PLACE FOR THIS FOR FRIDAY AND SATURDAY
AFTERNOONS/EVENINGS IN FWZS 624, 625, 284, AND 285. CONDITIONS WILL
EASE DURING THE OVERNIGHT PERIOD, WITH GENERALLY POOR TO MODERATE
RECOVERIES, POOREST ALONG THE WARNERS OF MODOC COUNTY.
THE DRY, DIURNALLY BREEZY PATTERN LOOKS TO LAST THIS WEEKEND AND
INTO EARLY NEXT WEEK. BUT, TEMPERATURES SHOULD ALSO LOWER SOME
COMPARED TO EARLIER THIS WEEK.
MFR WATCHES/WARNINGS/ADVISORIES
OR...FIRE WEATHER WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
EVENING FOR ORZ624-625.
RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR ORZ617-
622>625.
CA...FIRE WEATHER WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY
EVENING FOR CAZ284-285.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY FROM 11 PM THIS EVENING
TO 11 AM PDT THURSDAY FOR PZZ370-376.
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