743
FXUS66 KMFR 051014
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
314 AM PDT SUN JUL 5 2026
DISCUSSION
MARINE STRATUS HAS SPILLED INTO THE COQUILLE VALLEY THIS MORNING
WITH SOME MID LEVEL CLOUDS MOVING IN FROM CALIFORNIA AS AN UPPER
LEVEL LOW SPINS OFF THE COAST OF CALIFORNIA. THE MAIN WEATHER
FEATURE TODAY WILL BE THE AFTERNOON THUNDERSTORMS EAST OF THE
CASCADES. THE LATEST SPC HREF HAS A BULLSEYE RIGHT OVER LAKE
COUNTY WITH A 40 TO 50 PERCENT CHANCE OF LIGHTNING WITHIN 20KM OF
A POINT. WIND SHEAR IS ABOUT 20 KNOTS OUT OF THE SOUTH WEST.
FORECAST SOUNDINGS SHOW THE TYPICAL INVERTED V SOUNDINGS IN
SOUTHERN OREGON WITH MIXING UP 4KM ABOVE GROUND LEVEL, SO GUSTY
WINDS TO 40 KNOTS SEEM PROBABLE IN THESE THUNDERSTORMS.
THUNDERSTORMS COULD CONTINUE WELL INTO THE EVENING AND EARLY
OVERNIGHT HOURS, ALTHOUGH THEY SHOULD START TO DIE AROUND 8Z
MONDAY. THE UPPER LEVEL LOW WEAKENS AND JUST A BUNCH OF VORTICITY
FROM THAT LOW EVENTUALLY MOVES IN BY MONDAY. WITH AMPLE HEATING
AND ENOUGH MOISTURE, THUNDERSTORMS REMAIN IN THE FORECAST EAST OF
THE CASCADES ON MONDAY AFTERNOON. AGAIN, PROBABILITIES FOR CLOUD
TO GROUND LIGHTNING ARE AROUND 50 TO 70 PERCENT WITHIN LAKE
COUNTY, WHICH IS PRETTY HIGH COMPARED TO WHAT WE USUALLY SEE.
THOSE PROBABILITIES DROP OFF SIGNIFICANTLY FARTHER TO THE WEST AND
SOUTH.
BY TUESDAY EVENING, A 500 MB TROUGH WILL PUSH INTO THE PACIFIC
NORTHWEST. THIS WILL BRING SOME STRONGER NORTHWEST FLOW TO THE
REGION. SOME DATA SHOWS A DISSIPATING COLD FRONT MOVING CLOSER TO
THE COAST. IN ANY CASE, TEMPERATURES SHOULD TREND A FEW DEGREES
COOLER ON WEDNESDAY WITH MEDFORD TRENDING 5 DEGREES COOLER BASED
ON THE LATEST FORECAST. WITH THIS UPPER LEVEL LOW PUSHING INLAND,
ISOLATED SHOWERS OR THUNDERSTORMS CAN'T BE RULED OUT ON TUESDAY
EVENING. THE ECMWF ENSEMBLE SHOWS SPOTTY QPF AROUND MOST OF
CENTRAL OREGON, WHICH COULD CLIP NORTHERN LAKE OR KLAMATH COUNTIES
BEFORE CONDITIONS DRY WEDNESDAY.
AS FOR THE REMAINDER OF THE WEEK, WE REMAIN IN A ZONAL FLOW
PATTERN WITH TEMPERATURES RIGHT AROUND SEASONAL NORMALS FOR THIS
TIME OF YEAR. FOR REFERENCE, MEDFORD'S NORMAL HIGH IS IN THE
UPPER 80'S FOR LATE JULY AND WE'RE FORECASTING HIGHS IN THE LOWER
90'S. THE EXTREME FORECAST INDEX IS ALSO SUGGESTING A RATHER
MUNDANE WEEK WEATHER WISE COMPARED TO THE TYPICAL JULY. MONDAY IS
THE ONLY DAY OF INTEREST WITH CONVECTIVE AVAILABLE POTENTIAL
ENERGY(CAPE) EFI VALUES AROUND 0.7 IN LAKE COUNTY. THAT SUGGESTS
THERE COULD BE MORE CAPE THAN USUAL FOR EARLY JULY IN LAKE COUNTY.
-SMITH
AVIATION...05/06Z TAFS
MARINE STRATUS IS STARTING TO DEVELOP
ALONG THE OREGON COAST, WITH LIFR LEVELS ALREADY AT BROOKINGS AND
IFR LEVELS EXPECTED AT NORTH BEND TONIGHT OR EARLY SUNDAY
MORNING. THESE LEVELS LOOK TO CONTINUE INTO LATE SUNDAY MORNING
BEFORE THE MARINE LAYER BREAKS UP AND GUSTY NORTHERLY WINDS BUILD
ON SUNDAY AFTERNOON.
INLAND TERMINALS GENERALLY LOOK TO STAY AT VFR LEVELS WITH NORMAL
DIURNAL WINDS. THUNDERSTORMS MAY DEVELOP IN LAKE AND EASTERN KLAMATH
COUNTIES ON SUNDAY AFTERNOON. WHILE ACTIVITY IS NOT EXPECTED OVER
KLAMATH FALLS AT THIS POINT, A STRAY THUNDERSTORM COULD DEVELOP
NEARBY. THUNDERSTORM ACTIVITY SHOULD TAPER OFF TOWARDS THE END OF
THE TAF PERIOD. -TAD
MARINE...UPDATED 200 AM PDT SATURDAY, JULY 4, 2026
GUSTY NORTH
WINDS WILL PERSIST THROUGH MONDAY WITH VERY STEEP SEAS AROUND 10
FEET AT 7 SECONDS EXPECTED SOUTH OF CAPE BLANCO AND BEYOND 10 NM
FROM SHORE. ISOLATED GALE GUSTS ARE POSSIBLE SOUTH OF GOLD BEACH
AND WITHIN 20 NM OR SHORE SUNDAY EVENING. WINDS LOWER MONDAY INTO
WEDNESDAY BUT STEEP WEST SWELL IS POSSIBLE.
FIRE WEATHER...UPDATED 1200 PM PDT SATURDAY, JULY 4, 2026
THERE
IS A SLIGHT CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS SUNDAY
EAST OF THE CASCADES, AND MONDAY ALONG AND EAST OF THE CASCADES AND
OVER THE KLAMATHS AND SISKIYOUS. THERE IS A POSSIBILITY THAT SOME OF
THESE SHOWERS AND AN ISOLATED THUNDERSTORM OR TWO LINGER ON INTO
SUNDAY NIGHT/EARLY MONDAY MORNING OVER MODOC AND LAKE COUNTIES.
THERE SHOULD BE ENOUGH MOISTURE TO PRODUCE RAIN WITHIN THE CORES OF
THESE THUNDERSTORMS, BUT A FEW MORE HIGH BASED STORMS, OR THOSE
ALONG THE PERIPHERY OF THE DRIER AIR, COULD PRODUCE VERY LITTLE OR
NO RAIN AT THE SURFACE. ALONG WITH LIGHTNING, GUSTY AND ERRATIC
WINDS WILL BE A CONCERN FOR ANY STORMS THAT DEVELOP (ESPECIALLY THE
DRIER ONES).
OTHERWISE, HIGH TEMPERATURES REMAIN AROUND 5 TO 10 DEGREES ABOVE
NORMAL, AND AFTERNOON BREEZES REMAIN TYPICAL TO SLIGHTLY ENHANCED
DURING THE NEXT WEEK. THIS WILL RESULT IN VERY DRY CONDITIONS,
GENERALLY JUST SHY OF CRITICAL WIND AND HUMIDITY THRESHOLDS,
ESPECIALLY TUESDAY AND WEDNESDAY AS A DRY COLD FRONT PASSES THROUGH
THE REGION. ANOTHER DRY FRONTAL PASSAGE IS POSSIBLE NEXT WEEKEND.
MFR WATCHES/WARNINGS/ADVISORIES
OR...RED FLAG WARNING FROM 3 PM THIS AFTERNOON TO 9 PM PDT THIS
EVENING FOR ORZ624-625.
CA...NONE.
PACIFIC COASTAL WATERS...SMALL CRAFT ADVISORY UNTIL 2 AM PDT MONDAY
FOR PZZ350-356-370.
HAZARDOUS SEAS WARNING UNTIL 2 AM PDT MONDAY FOR PZZ356-376.
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