249
FXUS66 KMFR 191134 CCA
AFDMFR
AREA FORECAST DISCUSSION...CORRECTED
NATIONAL WEATHER SERVICE MEDFORD OR
434 AM PDT WED AUG 19 2026
KEY MESSAGES
* ABOVE NORMAL TEMPERATURES ARE EXPECTED THE NEXT COUPLE OF DAYS
BEFORE TRENDING BACK NEAR NORMAL FRIDAY ONWARD
* DRY CONDITIONS AND TYPICAL AFTERNOON BREEZES CONTINUE, BUT
FRIDAY AND SATURDAY WILL SEE AN UPTICK WITH ENHANCED BREEZES
* ISOLATED THUNDERSTORMS ARE POSSIBLE FRIDAY AFTERNOON ALONG THE
CASCADES AND POSSIBLY EASTSIDE AREAS THROUGH THE EVENING HOURS
* AREAS OF SMOKE REMAIN POSSIBLE ACROSS WESTERN SISKIYOU COUNTY
AND PARTS OF KLAMATH AND LAKE COUNTIES DUE TO NEARBY WILDFIRES
DISCUSSION (TODAY THROUGH TUESDAY)
OVERALL, VERY TYPICAL SUMMER-LIKE PATTERN WITH LIMITED IMPACTS
OUTSIDE OF FIRE WEATHER. THE GENERAL PATTERN WILL BE NOTED BY HIGH
PRESSURE OVER THE DESERT SOUTHWEST AND A CLOSED LOW OFF THE COAST
AROUND 137W AND 35N. THIS WILL MAINTAIN SOUTH TO SOUTHWESTERLY
FLOW ALOFT THROUGH MUCH OF THIS FORECAST. THE BIG QUESTION WILL BE
HOW FAR EAST WILL THE UPPER LOW MOVE TOWARDS THE PACNW ON
THURSDAY/FRIDAY. THIS WILL LIKELY PLAY A LARGE ROLE ON OUR FIRE
WEATHER CONDITIONS (WIND/LOW RH) AND THUNDERSTORM CHANCES. THE
SIGNAL IS CURRENTLY WEAK FOR THUNDERSTORM CHANCES, BUT WE DO HAVE
MOISTURE AND WEAK INSTABILITY ACROSS THE REGION, SO THE ADDED
DYNAMICS ALOFT COULD HELP PRODUCE A THUNDERSTORM OR TWO FRIDAY
AFTERNOON/EARLY EVENING. IT WILL BE A BATTLE BETWEEN THE CLOSED
LOW AND THE HIGH PRESSURE OVER THE DESERT SOUTHWEST. IF THE CLOSED
LOW IS ALLOWED TO PUSH EASTWARD BEFORE ITS NORTH/NORTHEAST
TRAJECTORY, WE MIGHT SEE MORE COVERAGE ON THE EASTSIDE. STILL SOME
UNCERTAINTY, ESPECIALLY WITH CAPE VALUES BEING ON THE LOWER END.
THE TAKEAWAY HERE IS THAT WE WILL SEE INCREASED RISK FOR FIRE
WEATHER CONDITIONS FROM EITHER LIGHTNING POTENTIAL OR THE
COMBINATION OF WINDS AND LOW RH. IN FACT, WE COULD SEE BOTH OF
THESE SCENARIOS COME TO FRUITION WITH MAIN DIFFERENCES IN TIMING
OF SAID THREATS. AS THE LOW PUSHES NORTH AND EAST, WE WILL REMAIN
UNDER SOUTH/SOUTHWESTERLY FLOW THROUGH EARLY NEXT WEEK. THIS
PATTERN WILL KEEP US OVERALL DRY WITH THE MAIN WEATHER HAZARD
REVOLVING AROUND FIRE WEATHER POTENTIAL WHICH IS TYPICAL FOR THIS
TIME OF YEAR.
AVIATION (12Z TAFS)
MARINE STRATUS CONTINUES TO IMPACT THE COAST THIS MORNING
BRINGING IFR CONDITIONS TO KOTH. THIS PATTERN WILL BRING RELIEF
THIS AFTERNOON, BUT THE MARINE LAYER IS EXPECTED TO REESTABLISH
AND BRING IFR CONDITIONS AGAIN THIS EVENING/OVERNIGHT. OTHERWISE,
HIGH CLOUDS AND TYPICAL AFTERNOON BREEZES ARE EXPECTED FARTHER
INLAND WHICH WILL RESULT IN VFR CONDITIONS THROUGH THIS CYCLE.
MARINE (UPDATED AT 330 AM AUG 19TH)
GUSTY NORTH WINDS AND STEEP SEAS ARE EXPECTED SOUTH OF CAPE
BLANCO THROUGH THIS EVENING. CONDITIONS ARE EXPECTED TO IMPROVE
THURSDAY AND FRIDAY. A THERMAL TROUGH WILL REDEVELOP ALONG THE
COAST THIS WEEKEND BRINGING A RETURN OF STRONG NORTH WINDS AND
STEEP SEAS. ONCE AGAIN, STRONGEST WINDS AND HIGHEST SEAS ARE MOST
LIKELY SOUTH OF CAPE BLANCO.
FIRE WEATHER (UPDATED AT 330 AM AUG 19TH)
STARTING THURSDAY, THE COMBINATION OF WINDS AND LOW RH WILL
RESULT IN AT LEAST ELEVATED FIRE WEATHER CONCERNS THROUGH THE
WEEKEND AND INTO EARLY NEXT WEEK. THE MAIN AREAS OF INTEREST WILL
BE EASTSIDE AREAS AND PARTS OF NORTHERN CALIFORNIA. AT LEAST IN
THE SHORT/NEAR TERM, WE NEED TO KEEP AN EYE ON FRIDAY AND SATURDAY
FOR CONDITIONS APPROACHING CRITICAL THRESHOLDS. FRIDAY WE HAVE AN
APPROACHING UPPER LEVEL LOW THAT WILL BRING ENHANCED BREEZES
COUPLED WITH LOW RH FOR EASTSIDE AREAS AND PARTS OF NORTHERN
CALIFORNIA. IN ADDITION TO THE LOW RH AND WINDS, WE WILL HAVE
INCREASED CHANCES FOR THUNDERSTORMS ON FRIDAY AS WELL, MAINLY
ALONG THE CASCADES AND NORTH. THAT SAID, SOME SIGNS ARE POINTING
TOWARDS INCREASED COVERAGE FOR EASTSIDE AREAS. ON SATURDAY, THE
THUNDERSTORM THREAT LIKELY SHIFTS NORTH AND EAST OF OUR AREA, BUT
WE MAY STILL HAVE THOSE ENHANCED BREEZES STICKING AROUND FOR
ANOTHER AFTERNOON/EARLY EVENING. THIS COMBINED WITH ANOTHER DRY
AFTERNOON WILL BRING AT LEAST ELEVATED FIRE WEATHER CONCERNS.
COVERAGE WISE, FRIDAY AND SATURDAY WILL BE THE MOST NOTEWORTHY
DAYS REGARDING FIRE WEATHER CONCERNS THAT COULD TILT TOWARDS
CRITICAL THRESHOLDS. ULTIMATELY, THE THREAT OF ELEVATED TO
PERHAPS CRITICAL FIRE WEATHER CONDITIONS WILL CONTINUE INTO EARLY
NEXT WEEK.
MFR WATCHES/WARNINGS/ADVISORIES
OR...CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 11 PM PDT THIS
EVENING FOR PZZ356-376.
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