117
FXUS66 KMFR 261041
AFDMFR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MEDFORD OR
341 AM PDT SAT JUL 26 2025
DISCUSSION
IT WAS ANOTHER ACTIVE THUNDERSTORM DAY DURING FRIDAY IN MODOC AND
SISKIYOU COUNTY. THE NATIONAL LIGHTNING DETECTION NETWORK(NLDN)
PICKED UP ON ~775 CLOUD TO GROUND FLASHES WITH THE EARTH NETWORKS
TOTAL LIGHTNING NETWORK(ENTLN/ENI) PICKING UP ~4000. IN ANY CASE,
IT WILL BE ANOTHER ACTIVE IN NORTHERN CALIFORNIA, ALTHOUGH NOTABLY
LOWER COMPARED TO THE LAST FEW DAYS. THE STORM PREDICTION CENTER
HREF IS PREDICTING ABOUT A 20 TO 30 PERCENT CHANCE OF CLOUD TO
GROUND LIGHTNING THIS AFTERNOON IN MODOC COUNTY, WHICH IS NOTABLY
LOWER COMPARED TO YESTERDAY.
LIKE THE LAST FEW DAYS, STORM MOTION WILL BE MINIMAL, SO WE SHOULD
SEE SOME WETTING RAIN UNDER THESE THUNDERSTORMS WITH PRECIPITABLE
WATER(PWAT) VALUES AROUND 0.65 NEAR ALTURAS(KAAT).
MODELS ARE NOW SHOWING THUNDERSTORMS ON SUNDAY AFTERNOON AND
EVENING IN NORTHERN CALIFORNIA AND LOCATIONS EAST OF THE
CASCADES. THIS IS LOOKING PRETTY SCATTERED RIGHT NOW, ALTHOUGH THE
CLOUD TO GROUND LIGHTNING PROBABILITIES ON THE SPC HREF
PROBABILITIES IS ABOUT 30 TO 50 PERCENT, WHICH IS STILL PRETTY
GOOD. STORM MOTION SHOULD BE A LITTLE BETTER ON SUNDAY EVENING
WITH MORE NOTABLE SOUTH 10 TO 15 KNOTS SOUTHERLY FLOW.
BEYOND THE NEXT FEW DAYS, IT SEEMS MODELS ARE PICKING UP ON A
CONSISTENT THUNDERSTORM THREAT ACROSS THE REGION MONDAY THROUGH
THURSDAY. IT IS PRETTY IMPRESSIVE TO SEE THIS PERSISTENT
THUNDERSTORM THREAT FOR ALMOST 7 DAYS STRAIGHT WITH PERSISTENT
TROUGHING IN THE PACIFIC NORTHWEST. THE ONE THING THAT DOES STAND
OUT RIGHT NOW IS THE POTENTIAL FOR SOME NOCTURNAL THUNDERSTORMS
WEDNESDAY NIGHT BASED OFF OF THE QPF FIELDS FROM THE ECMWF
ENSEMBLE. A NOTABLE AMOUNT OF MEMBERS(~40%) ARE SHOWING
CONVECTION OVERNIGHT SOMEWHERE OVER OREGON WITH SOME MEMBERS
PUSHING CONVECTION FARTHER NORTH INTO PQRS AREA AND 1 OR 2 AS
FARTHER EAST INTO BOIS CWA. STILL A LOT TO SORT OUT, BUT IT WILL
BE SOMETHING THAT NEEDS TO BE WATCHED IN FUTURE FORECASTS.
-SMITH
AVIATION...27/06Z TAFS
WIDESPREAD IFR AND AREAS OF LIFR ALONG
THE COAST WILL PERSIST THROUGH SATURDAY MORNING. AREAS OF IFR/MVFR
ARE EXPECTED TO SPREAD INTO THE NORTHWEST UMPQUA BASIN EARLY
SATURDAY MORNING, MAINLY NEAR AND NORTH OF ROSEBURG. THEN EXPECT
CLEARING TO VFR IN THE UMPQUA AND ALONG THE COAST LATE SATURDAY
MORNING INTO EARLY SATURDAY AFTERNOON. HOWEVER, AREAS OF MVFR MAY
PERSIST INTO THE LATE AFTERNOON ALONG THE COAST. WIDESPREAD IFR
CONDITIONS RETURN TO THE COAST EARLY SATURDAY EVENING.
ELSEWHERE, VFR PREVAILS BUT ISOLATED THUNDERSTORMS WILL DEVELOP
AGAIN SATURDAY AFTERNOON AND EVENING, MAINLY ACROSS EASTERN
SISKIYOU, MODOC, AND LAKE COUNTIES. THESE COULD LOCALLY AND
TEMPORARILY REDUCE VISIBILITY/CEILINGS TO IFR/MVFR. ANY
THUNDERSTORMS WILL HAVE THE ABILITY TO PRODUCE CLOUD TO GROUND
LIGHTNING, STRONG, GUSTY OUTFLOW WIND GUSTS OF 30 TO 50 MPH, BRIEF,
HEAVY RAIN AND SMALL HAIL.
MARINE...UPDATED 300 AM PDT FRIDAY, JULY 25, 2025
SUB-ADVISORY
NORTH WINDS AND LOW SEAS OF 5 FT OR LESS, WILL PERSIST THROUGH
THE WEEKEND INTO EARLY NEXT WEEK. OF NOTE, WINDS WILL BRIEFLY
APPROACH SMALL CRAFT ADVISORY LEVELS THROUGH THIS EVENING, BETWEEN
PORT ORFORD AND GOLD BEACH, 2 TO 20 NM FROM SHORE. WINDS THEN
LOWER OVERNIGHT. AREAS OF FOG AND LOW STRATUS WILL ALSO PERSIST
THROUGH THIS TIME. WINDS AND SEAS MAY TREND SLIGHTLY HIGHER AROUND
TUESDAY OF NEXT WEEK.
MFR WATCHES/WARNINGS/ADVISORIES
OR...NONE.
CA...NONE.
PACIFIC COASTAL WATERS...NONE.
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