358
FXUS66 KEKA 112336
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
436 PM PDT FRI SEP 11 2026
AVIATION...00Z UPDATE
VFR CONDITIONS PERSIST THIS AFTERNOON
FOR THE COAST, BEFORE MVFR TO IFR OF BKN-OVC CEILINGS DEVELOP
OVERNIGHT AS AN INCOMING TROUGH DEEPENS AND WEAKENS THE MARINE
LAYER. AN APPROACHING FRONT WILL ALSO TURN WINDS SOUTHERLY NEAR
CEC, WHICH MAY LEAD TO CONTINUED VFR CEILINGS. INTERIOR AREAS ARE
LIKELY TO REMAIN VFR FOR THE NEXT 24 HOURS WITH STRONGER GUSTY
AFTERNOON BREEZES EXPECTED TOMORROW, PRIMARILY OUT OF THE NW.
SMOKE WILL CONTINUE TO BE AN ISSUE IN LAKE COUNTY INCREASING
POTENTIAL FOR MOUNTAIN VISIBILITY ISSUES. THE FIRST ROUND OF LIGHT
RAIN SHOWERS IS LIKELY TO ARRIVE TOMORROW AFTERNOON TO CEC, YET
MVFR TO VFR IS EXPECTED TO REMAIN AS THIS SYSTEM IS TRENDING
FURTHER NORTH THAN CA.
PREV DISCUSSION
/ISSUED 135 PM PDT FRI SEP 11 2026/
KEY MESSAGES...
* MUCH COOLER INTERIOR TEMPERATURES LIKELY THIS WEEKEND.
* CHANCES FOR LIGHT RAINFALL FOR DEL NORTE AND NORTHERN HUMBOLDT
SATURDAY.
* ELEVATED FIRE DANGER EACH AFTERNOON THROUGH SATURDAY FOR THE
INTERIOR.
* RED FLAG WARNING IN EFFECT FOR LAKE COUNTY SATURDAY FOR STRONG
WINDS AND LOW RELATIVE HUMIDITY.
SYNOPSIS...COOLER TEMPERATURES ARE EXPECTED THROUGH INTO THE
WEEKEND. LIGHT RAIN IS POSSIBLE FOR THE DEL NORTE AND NORTHERN
HUMBOLDT SATURDAY. WESTERLY TO NORTHWESTERLY WINDS WILL BRING
ELEVATED TO CRITICAL FIRE DANGER FOR THE INTERIOR SATURDAY.
DISCUSSION...INTERIOR TEMPERATURES WILL WILL BE OVER 10 DEGREES
COOLER FRIDAY AS TROUGHING FROM THE NW BEGINS TO INFLUENCE THE
REGION. THE TROUGH AND ASSOCIATED FRONT WILL SWING THROUGH ON
SATURDAY, CONSIDERABLY LOWERING INTERIOR TEMPERATURES TO THE 70S
AND 80S. THE FRONT WILL ALSO BRING A CHANCE FOR RAIN TO DEL NORTE
AND NORTHERN HUMBOLDT COUNTIES. DEL NORTE HAS AROUND AN 80-90%
CHANCE TO SEE MEASURABLE RAIN, WHILE NORTHERN HUMBOLDT HAS AROUND
A 20-40% CHANCE, MAINLY NORTH OF EUREKA. THE CHANCE FOR WETTING
RAIN (OVER 0.1") IS AROUND 20% IN NORTHERN HUMBOLDT AND 60-70% IN
DEL NORTE. THERE IS SOME INSTABILITY MODELED WITH THIS SYSTEM,
WHICH MAY ALLOW FOR A THUNDERSTORM TO DEVELOP IN AN ESPECIALLY
STRONG SHOWER.
POST FRONTAL WESTERLY WINDS WILL STRENGTHEN SATURDAY AFTERNOON TO
THE EASTERN PORTIONS OF THE AREA. THE PROBABILITY OF WIND GUSTS
OVER 30 MPH ARE ABOVE 50% FOR MUCH OF EASTERN LAKE COUNTY,
EASTERN MENDOCINO, AND THE TRINITY RIVER VALLEY IN EASTERN TRINITY
COUNTY. THIS WILL ELEVATE FIRE WEATHER CONCERNS, PARTICULARLY
OVER LAKE COUNTY WHERE THE STRONGEST WINDS WILL COINCIDE WITH DRY
CONDITIONS. A RED FLAG WARNING IS IN EFFECT FOR LAKE COUNTY
SATURDAY, BUT ELEVATED FIRE WEATHER CONDITIONS WILL EXIST FOR ALL
THE INTERIOR AREAS LISTED ABOVE. THERE ARE ALSO CHANCES THIS FIRE
THREAT CONTINUES SUNDAY NIGHT AND MONDAY FOR THE FAR EASTERN
PORTIONS OF THE AREA. SEE THE FIRE WEATHER SECTION BELOW.
AN OMEGA-BLOCK PATTERN IS LIKELY TO DEVELOP RIGHT OFF THE PACIFIC
NORTHWEST COAST, WITH TROUGHING REMAINING FAR EAST AND FAR WEST.
SLIGHTLY OVER HALF OF ENSEMBLE MEMBERS DO SHOW AN ELONGATED
POSITIVELY TILTED TROUGH OR CUTOFF LOW OVER THE AREA WEDNESDAY.
THIS WILL CONTAIN LITTLE MOISTURE AND MAY ONLY RESULT IN A
SLIGHTLY DEEPENED MARINE LAYER AND PERHAPS SOME MODEST INSTABILITY
IN THE HIGHER TERRAIN. REGARDLESS, A DRY, NEAR-NORMAL PATTERN
LOOKS LIKELY FOR THE FOLLOWING WEEK AS THE OMEGA BLOCK STALLS ANY
STORM TRACK FOR NW CALIFORNIA. /JB
MARINE...NORTHERLY WINDS INCREASE ACROSS THE SOUTHERN WATERS
FRIDAY WHILE EASING SOME IN THE NORTHERN WATERS NORTH OF CAPE
MENDOCINO. LOCALIZED GALE CONDITIONS CAN BE EXPECTED AROUND AND
SOUTH OF CAPE MENDOCINO THIS AFTERNOON AND EVENING. SHORT PERIOD
SEAS UP TO 10 FT WILL BE GENERATED IN THE LEE OF CAPE MENDOCINO
FROM THESE WINDS. WINDS AND SEAS QUICKLY EASE SATURDAY AS A
TROUGH MOVES IN. THIS WILL BRING THUNDERSTORM CHANCES TO THE
NORTHERN WATERS, MAINLY CLOSER TO THE OREGON BORDER.
FIRE WEATHER...A TROUGHING PATTERN WILL BRING BREEZIER WINDS,
MUCH COOLER TEMPERATURES, AND A DEEPER MARINE LAYER. WETTING RAIN
IS POSSIBLE FOR DEL NORTE AND FAR NORTHERN HUMBOLDT. BREEZY
AFTERNOON WINDS CONTINUE TODAY WITH GUSTS OF UP TO 20 MPH IN LAKE,
EASTERN MENDOCINO, AND EASTERN TRINITY COUNTIES. THIS WILL ELEVATE
FIRE WEATHER CONDITIONS AS AFTERNOON RH REMAINS IN THE TEENS AND
20S. SATURDAY, STRONGER WINDS ARE FORECAST WITH GUSTS UP TO 35 MPH
ARE POSSIBLE IN LAKE, SOUTHERN MENDOCINO, AND EASTERN TRINITY
COUNTIES SATURDAY AFTERNOON. RH WILL RISE WITH THIS ONSHORE PUSH
OF WINDS TO THE 20S AND 30S, BUT MUCH STRONGER WIND GUSTS OF 25 TO
35 MPH WILL SUPPORT CRITICAL FIRE WEATHER CONDITIONS, PARTICULARLY
IN LAKE COUNTY. A RED FLAG WARNING HAS BEEN ISSUED IN LAKE COUNTY
FROM 10 AM SATURDAY TO 2 AM SUNDAY. OTHER AREAS OUTSIDE LAKE
COUNTY WILL STILL SEE ELEVATED FIRE DANGER, INCLUDING EASTERN
MENDOCINO AND TRINITY COUNTY, DESPITE NOT BEING WITHIN THE RED
FLAG WARNING AREA.
WINDS EASE SUNDAY AND RHS TICK UP SLIGHTLY INTO THE HIGH 20S TO
THE HIGH 30S FOR THE EASTERN INTERIOR. AREAS CLOSER TO THE COAST
COULD SEE AFTERNOON RHS IN THE 50S WITH A MUCH DEEPER MARINE
LAYER. SUNDAY NIGHT INTO MONDAY, AN INCREASE OF NORTHERLY WINDS
DOWN THE CENTRAL VALLEY MAY ELEVATE FIRE CONDITIONS AGAIN FOR THE
EASTERN PORTIONS OF THE AREA, PARTICULARLY EASTERN LAKE COUNTY
SHOULD THE WINDS END UP ON THE STRONGER END. RH DOES TREND
UPWARDS, SO THE THREAT MAY BE MUTED SOMEWHAT, BUT IT IS SOMETHING
TO WATCH. /JB
EKA WATCHES/WARNINGS/ADVISORIES
CA...
RED FLAG WARNING FROM 10 AM SATURDAY TO 2 AM PDT SUNDAY FOR
CAZ418>421.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY UNTIL 3 AM PDT SATURDAY FOR PZZ455-475.
NOTE: THE FULL FORECAST DISCUSSION IS NOW REGULARLY ISSUED BETWEEN
10 AM/PM AND 1 PM/AM. ADDITIONAL UPDATES WILL BE ISSUED AS NEEDED.
VISIT US AT HTTPS://WWW.WEATHER.GOV/EUREKA
FOLLOW US ON FACEBOOK AND TWITTER AT:
HTTPS://WWW.FACEBOOK.COM/NWSEUREKA
HTTPS://WWW.TWITTER.COM/NWSEUREKA
FOR FORECAST ZONE INFORMATION
SEE THE FORECAST ZONE MAP ONLINE:
HTTPS://WWW.WEATHER.GOV/IMAGES/EKA/ZONEMAP.PNG
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page