679
FXUS66 KEKA 040705
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
1205 AM PDT THU SEP 4 2025
SYNOPSIS
ANOTHER HOT AND DRY DAY EXPECTED TODAY FOR THE INTERIOR.
THERE IS A SLIGHT CHANCE FOR DRY THUNDERSTORMS IN DEL NORTE COUNTY
THIS AFTERNOON AND EVENING. STRATUS LIKELY TO REMAIN PERSISTENT ON
THE COAST. SUNDAY NIGHT INTO MONDAY THERE IS A CHANCE FOR A WETTING
RAIN IN THE NORTHERN PORTION OF THE AREA AND INTERIOR HIGHS DOWN
INTO THE 70S.
DISCUSSION
LOOKING AT THE UPPER-LEVELS, THERE IS AN UPPER LOW
MOVING TO THE NORTH, WHILE AN ADDITIONAL BROAD UPPER LOW IS CENTERED
OFF THE COAST OF BRITISH COLUMBIA. THIS TROUGH IS MODELED TO DIP
TOWARD THE PACIFIC NORTHWEST TODAY AND BECOME A CUTOFF LOW BY
FRIDAY. STILL, HIGH PRESSURE TO THE EAST SUPPORTS WARM TEMPERATURES
IN THE INTERIOR TODAY, THOUGH THEY MAY BE A FEW DEGREES COOLER TODAY
THAN YESTERDAY. A DEEPER MARINE LAYER WILL LIKELY MODERATE
TEMPERATURES SOME IN THE RIVER VALLEYS NEAR THE COAST. DESPITE THE
DEEPER MARINE LAYER, THE MARINE INVERSION REMAINS STRONG AND THE
IMMEDIATE COASTLINE IS LIKELY TO REMAIN CLOUDY THROUGH THE AFTERNOON
AGAIN.
WARM AFTERNOON TEMPERATURES AND MOISTURE ALOFT MAY SUPPORT ISOLATED
THUNDERSTORMS THIS AFTERNOON AND EVENING. THE HIGHEST OF THE
INSTABILITY AND MOISTURE COMBINATION IS IN WESTERN SISKIYOU AND
EASTERN DEL NORTE COUNTIES. WHILE CAMS ARE NOT CURRENTLY SHOWING ANY
STORMS DEVELOPING OVER DEL NORTE, IT CANNOT BE RULED OUT.
THE CUTOFF LOW CONTINUES TO MOVE CLOSER TO THE AREA FRIDAY. THIS
WILL DEEPEN THE MARINE LAYER FURTHER. PRECIPITATION CURRENTLY
APPEARS LIMITED TO COASTAL DRIZZLE, BUT A FEW ENSEMBLE MEMBERS ARE
SHOWING THE POTENTIAL FOR MORE PRECIPITATION. THERE'S AROUND A 20%
CHANCE FOR A TENTH OF AN INCH ALONG COASTAL HUMBOLDT AND DEL NORTE
THURSDAY NIGHT INTO FRIDAY. INSTABILITY IN INTERIOR DEL NORTE AND
WESTERN SISKIYOU CONTINUES TO BE HIGH FRIDAY AFTERNOON, BUT MOISTURE
DIMINISHES SOMEWHAT AND NUDGES WESTWARD MORE INTO SISKIYOU.
THUNDERSTORMS ARE NOT LIKELY IN DEL NORTE, BUT WILL NEED TO BE
WATCHED.
SUNDAY NIGHT INTO MONDAY THE TROUGH MOVES SOUTHWARD INTO THE PACIFIC
NORTHWEST. MODELS VARY ON HOW FAR SOUTH THIS WILL DIP, AND THIS WILL
BE THE MAIN FACTOR TO HOW MUCH PRECIPITATION WE RECEIVE. NBM IS
SHOWING AROUND A 70% CHANCE FOR AT LEAST A TENTH OF AN INCH OF RAIN
IN DEL NORTE, HUMBOLDT, AND TRINITY, WHILE CHANCES DROP TO 30-50% IN
MENDOCINO AND LAKE. CHANCES FOR AT LEAST A HALF INCH OF RAIN ARE
AROUND OR ABOVE 50% IN DEL NORTE, MUCH OF NORTHERN HUMBOLDT, AND THE
HIGHER ELEVATIONS OF TRINITY. ADDITIONAL SYSTEMS ARE POSSIBLE EARLY
TO MID NEXT WEEK. JB
AVIATION...04/06Z TAFS
PREVAILING LIFR CONDITIONS ALONG THE
COASTAL TERMINALS, WITH A DEEP MARINE LAYER. THE MCKINLEYVILLE AND
BODEGA BAY PROFILERS INDICATES A MARINE LAYER DEPTH UP TO AROUND
2000 FEET MSL. PATCHY DRIZZLE HAS BEEN OCCURRING ALONG THE COAST AS
A RESULT OF THIS SATURATED LAYER. ASIDE FROM THE MARINER LAYER, HIGH
LEVEL CLOUDS STREAMING EASTWARD ACROSS THE AREA. LOW CLOUDS ARE
EXPECTED TO LIFT TO IFR EARLY THURSDAY AFTERNOON, AND PERHAPS TO
MVFR LATE IN THE AFTERNOON. A DEEPER MARINE LAYER IS EXPECTED TO
DEVELOP THURSDAY NIGHT AS AN UPPER LEVEL TROUGH APPROACHES FROM THE
WEST. SURFACE WINDS FROM S AT 5 TO 10 KTS, SHIFTING WSW AFTER 19Z.
FOR INLAND AREAS: VFR CONDITIONS WITH HIGH LEVEL CLOUDS STREAMING
ACROSS THE AREA, INCLUDING IN KUKI. HREF SUGGEST SOME LOW CLOUDS AND
VSBY REDUCTION WITH IFR/MVFR CONDITIONS AROUND 11Z AT KUKI.
OTHERWISE, MAINLY VFR CONDITIONS IS EXPECTED TO PERSIST AT UKI WITH
SCT-BKN HIGH LEVEL CLOUDS. LIGHT SURFACE WINDS FROM S, INCREASING TO
6 TO 10 KTS AFTER 20Z, SHIFTING TO NNE AFTER 05/00Z. /ZVS
MARINE
MODERATE TO STRONG NORTHERLY WINDS IS EXPECTED TO PERSIST
ACROSS THE OUTER WATERS THROUGH THURSDAY MORNING, FOLLOWED BY GENTLE
TO MODERATE BREEZES. CURRENT STEEP SHORT PERIOD SEAS AROUND 6 TO 9
FEET WILL CONTINUE TO GRADUALLY SUBSIDE THROUGHOUT THE DAY ON
THURSDAY, WITH BELOW SMALL CRAFT ADVISORY CRITERIA THURSDAY
AFTERNOON. MEANWHILE, GENERALLY LIGHT TO MODERATE WINDS AND SEAS
AROUND 5 FEET AT 6 SECONDS ACROSS THE INNER WATERS. NORTHERLY WINDS
WILL CONTINUE TO DIMINISH FRIDAY AND INTO SATURDAY AS AN AREA OF LOW
PRESSURE APPROACHES FROM THE WEST. WINDS SHIFT TO SOUTHERLY AND
INCREASE AHEAD OF A FRONTAL SYSTEM THIS WEEKEND. STEEP SEAS WILL
PERSIST ACROSS THE OUTER WATER THROUGH THURSDAY AFTERNOON, AND THEN
SUBSIDE THROUGH THE WEEKEND. /ZVS
FIRE WEATHER
ANOTHER DAY OF WARM TEMPERATURES, LOW AFTERNOON RH,
AND POOR OVERNIGHT RECOVERIES IS EXPECTED TODAY. THERE IS A 10-15%
CHANCE FOR DRY THUNDERSTORMS IN EASTERN DEL NORTE AND WESTERN
SISKIYOU COUNTIES THIS AFTERNOON AND EVENING. ACTIVITY IS LIKELY TO
REMAIN LIMITED TO SISKIYOU, BUT A CELL DRIFTING INTO DEL NORTE IS
NOT OUT OF THE QUESTION. AN APPROACHING SHORTWAVE WILL IMPROVE RHS
AND LOWER TEMPERATURES FRIDAY INTO THE WEEKEND. LIGHT RAIN IS
POSSIBLE FRIDAY, WITH GREATER CHANCES IN DEL NORTE, BUT THIS IS
LIKELY TO BE REALIZED AS COASTAL DRIZZLE. STILL, RHS IMPROVE INTO
THE WEEKEND, WITH MODERATE TO GOOD OVERNIGHT RECOVERIES EXPECTED.
THERE IS A GREATER CHANCE FOR WETTING RAIN SUNDAY NIGHT INTO MONDAY,
WITH THE HIGHEST CHANCES IN HUMBOLDT, DEL NORTE, AND TRINITY
COUNTIES. WESTERLY WINDS MAY BE ELEVATED IN CHANNELED TERRAIN IN THE
INTERIOR MONDAY AFTERNOON. ADDITIONAL SYSTEMS ARE POSSIBLE EARLY TO
MID NEXT WEEK, BRINGING MORE CHANCES FOR WETTING RAIN. JB
EKA WATCHES/WARNINGS/ADVISORIES
CA...
NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY UNTIL 3 PM PDT THIS AFTERNOON FOR
PZZ470-475.
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