213
FXUS66 KEKA 302226
AFDEKA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE EUREKA CA
226 PM PST FRI JAN 30 2026
SYNOPSIS
CHANCE FOR LIGHT RAIN AND DRIZZLE IS FORECAST FOR
MOSTLY DEL NORTE AND HUMBOLDT COUNTIES LATE SATURDAY NIGHT AND
SUNDAY. OTHERWISE, DRY AND STABLE WEATHER IS FORECAST TO CONTINUE
THROUGH MOST OF NEXT WEEK.
DISCUSSION
ANOTHER DAY OF BOUNTIFUL SUNSHINE ACROSS NORTHWEST
CALIFORNIA TODAY AFTER THE MORNING FOG AND LOW CLOUDS BURNED OFF
IN THE INTERIOR VALLEYS. VARIABLE MID AND HIGH CLOUDS WILL
CONTINUE TO MOVE ACROSS THE AREA TONIGHT AND SATURDAY AS A DEEP
TROUGH DIGS OFFSHORE OVER THE CENTRAL PACIFIC WEST OF 140W WHILE
A MASSIVE UPPER RIDGE PUMPS OVER THE AREA AND NUDGES SLIGHTLY
EASTWARD. THE HIGH AND MID CLOUD COVER WILL LIKELY COUNTERACT THE
LONGWAVE COOLING FOR THE INTERIOR VALLEYS WHILE HIGHER ELEVATIONS
RESPOND TO THE LARGE SCALE ADIABATIC WARMING. A STRONG NOCTURNAL
INVERSION AND MOIST GROUNDS WILL LIKELY RESULT IN FOG AND LOW
CLOUDS TONIGHT AND EARLY SAT FOR MOSTLY TRINITY, HUMBOLDT AND
NORTHERN MENDOCINO COUNTIES.
DECAYING FRONTAL BOUNDARY WILL BRING A CHANCE FOR LIGHT RAIN OR
DRIZZLE TO PRIMARILY DEL NORTE AND HUMBOLDT COUNTIES LATE SATURDAY
NIGHT OR AFTER 2-4 AM SUNDAY. LIGHT RAIN OR DRIZZLE CHANCES INCREASE
AFTER 4 AM SUNDAY. HIGHEST CHANCE FOR 0.25 INCHES IN 12 HOURS END
4 PM SUNDAY IS FORECAST FOR DEL NORTE COUNTY, AROUND 40-50%. CHANCE
FOR > 0.25 INCHES IN 12 HOURS ENDING 4 PM SUNDAY IS MUCH LOWER
FOR MOST OF HUMBOLDT, 10-20%. CHANCE FOR > 0.10 INCHES IN 12
HOURS IS NOT VERY MUCH HIGHER FOR MOST OF HUMBOLDT, GENERALLY
AROUND 30-40%. THAT IS A LONG WAY OF SAYING NOT MUCH RAIN IS
EXPECTED. CHANCES FOR 0.01 TO 0.08 INCHES ARE HIGHER (>60%) AND
WILL IMPACT OUTER ACTIVITIES AND PROJECTS THAT CANNOT GET WET.
TIMING AND DURATION STILL REMAINS SOMEWHAT UNCERTAIN, BUT HIGHEST
CHANCES SEEM TO BE FROM 4 AM TO 12 PM SUNDAY. THE RAIN MAY NOT
LAST AS LONG EITHER AS THE FORECAST SEEMS TO SUGGEST. OTHER PORTIONS
OF THE FORECAST AREA, TRINITY AND MENDOCINO MAY SEE SOME LIGHT RAIN
OR DRIZZLE TOO ON SUNDAY, BUT RIGHT NOW WE ARE TALKING A TRACE TO
PERHAPS A FEW HUNDREDTHS. SOUTHEAST MENDO AND LAKE COUNTIES WILL
MOST LIKELY NOT GET ANY MEASURABLE RAIN. SAID ANOTHER WAY, AN 85%
TO 95% CHANCE FOR LESS THAN 0.01 INCHES IN 24 HOURS. THE SHORTWAVE
TROUGH LIFTS OUT TO THE NORTHEAST BY SUNDAY EVENING AND PRECIP
CHANCE WILL START TO DWINDLE EXCEPT FOR PERHAPS RESIDUAL DRIZZLE.
HIGH PRESSURE ALOFT WILL SPRING BACK UP BY MONDAY AND THEN
DOMINATE MOST ALL NEXT WEEK RESULTING IN MULTIPLE DAYS OF DRY
AND STABLE WEATHER. A SHALLOW MOIST AIR PUSH BEHIND THE FRONT
AND N-NW SURFACE FLOW MAY RESULT IN FOG AND LOW CLOUDS OVERNIGHT
SUNDAY INTO MONDAY MORNING IN THE INTERIOR VALLEYS. OTHERWISE, A
GENERAL WARMING TREND IS FORECAST FOR MUCH OF THE AREA EARLY TO
MID NEXT WEEK. HIGHS ARE FORECAST TO WARM UP INTO THE LOWER TO
MID 70'S IN THE INTERIOR NEXT WEEK. SOUTH FACING EXPOSURES AND
HIGHER TERRAIN STAND THE BEST CHANCE FOR HIGHS IN THE 70'S, WHILE
VALLEYS TRAPPED UNDER THE NOCTURNAL INVERSION WITH NIGHT AND
MORNING FOG MAY NOT WARM UP EVEN INTO THE LOWER 60S, ESPECIALLY IN
TRINITY AND NORTHERN HUMBOLDT. THE SUN ANGLE IS LOW AND MANY
NARROW VALLEYS DO NOT GET MUCH OR ANY SUN LIGHT THIS TIME OF
YEAR. AS IS COMMON FOR THIS TIME OF YEAR, OVERNIGHT LOW TEMPERATURES
WILL REMAIN ON THE CHILLY SIDE WITH SUBFREEZING MINIMUMS HIGHLY
PROBABLE FOR VALLEYS IN TRINITY AND PERHAPS PORTIONS HUMBOLDT,
LAKE AND NORTHERN MENDO.
LONGER RANGE MODELS ARE SUGGESTING A BREAK-THROUGH IN THE WESTERLIES
OR UNDERCUTTING OF THE BLOCKING RIDGE LATE NEXT WEEK AND NEXT
WEEKEND. THIS COULD BRING US SOME RAIN. DETAILS ON THE TIMING AND
AMOUNTS ARE ELUSIVE AT THIS POINT. NBM 24-HOUR PROBABILITY OF
EXCEEDANCE FOR 1" IS NOT VERY HIGH, ONLY 5 TO 20%, ENDING 4 AM
SUNDAY. STAND BY FOR MORE IN THIS NEXT WEEK.
AVIATION
FOG AND LOW CLOUDS WILL FORM AGAIN IN THE INTERIOR
VALLEYS OF TRINITY, HUMBOLDT AND NORTHERN MENDOCINO AGAIN
TONIGHT. LIFR CONDITIONS ARE HIGHLY PROBABLE FOR THE INTERIOR
VALLEYS (100% CHANCE). NO FOG FORMED AT KUKI THIS MORNING AND
NONE IS FORECAST FOR TONIGHT. HREF AND TO A LESSER EXTENT
DOWNSCALED BUFKIT PROFILES INDICATE HIGHER CHANCES OF IFR OR LIFR
AT COASTAL TERMINALS TONIGHT, PARTICULARLY AROUND HUMBOLDT BAY AND
NEAR OR OVER KACV. CHANCES ARE LOW AS USUAL, NO MORE THAN 40% BY
06Z. THIS WILL NEED TO WATCHED AND MONITORED FOR POSSIBLE
AMENDMENTS. OTHERWISE, VFR WITH VARIABLE MID AND HIGH CLOUDS WILL
CONTINUE TO PREVAIL TONIGHT. WINDS WILL GENERALLY REMAIN LIGHT
AND UNDER 12 KTS. STRONGER SOUTHERLY FLOW ALOFT (2000-3000 FT AGL)
INCREASES AGAIN TONIGHT AND SAT ACROSS INTERIOR DEL NORTE AND
NORTHERN HUMBOLDT COUNTY. CHANCE FOR LOW LEVEL WIND SHEAR AND/OR
SHALLOW TURBULENCE WILL INCREASE AGAIN ACROSS THE MOUNTAINS OF DEL
NORTE AND PERHAPS NORTHERN HUMBOLDT INTERIOR. THIS MAY HAVE IMPACTS
ON SMALL AND LIGHT-WEIGHT AIRCRAFT.
MARINE
WESTERLY SWELL HAS SUBSIDED BELOW 10 FT TODAY AND THE
ADVISORY FOR HAZARDOUS SEAS FOR SMALL CRAFT HAD ENDED. STEEP
SOUTHERLY WAVES AROUND 5 TO 7 FEET ARE FORECAST TO CONTINUE OVER
THE NORTHERN OUTER WATERS (PZZ470) THIS EVENING. THESE STEEP WIND
WAVES IN COMBINATION WITH A DECAYING WESTERLY SWELL NEAR 8 FEET
WILL YIELD SEAS AROUND 10 FEET ACROSS THE NORTHERN OUTER WATERS.
AN ADVISORY FOR SMALL CRAFT REMAINS IN EFFECT FOR COMBINED SEAS
AROUND 10 FEET FOR PZZ470 THIS EVENING. THE ADVISORY WILL HINGE
ON THE WIND WAVE GENERATION FROM NWPS WHICH MAY BE TOO HIGH.
OTHERWISE, A GENERALLY TRANQUIL WIND REGIME (5-15KT) IS FORECAST
TO CONTINUE ACROSS THE AREA TONIGHT THROUGH SATURDAY. SEAS SHOULD
LAY DOWN LATER TONIGHT INTO MUCH OF SATURDAY BEFORE A COUPLE OF
LONG PERIOD WESTERLY SWELL GROUPS (>16 SECONDS) PROPAGATE INTO THE
WATERS OVER THE WEEKEND. THE COMBINATION OF STEEP SOUTHERLY WIND
WAVES AND THESE WESTERLY SWELLS MAY YIELD SEAS AROUND 10-13 FEET,
ESPECIALLY ON SUNDAY. THE LARGEST LONG PERIOD SWELL GROUP (AROUND
12 FEET AT 16 SECONDS) IS FORECAST TO ARRIVE ON SUNDAY AND ANOTHER
ADVISORY FOR HAZARDOUS SEAS FOR SMALL CRAFT WILL BE NECESSARY.
ELEVATED SEAS NEAR 10 FEET DUE TO THIS WESTERLY SWELL TRAIN WILL
MOST LIKELY PERSIST INTO MONDAY AS A GENERALLY LIGHT TO MODERATE
NORTHERLY WIND REGIME TAKES SHAPE.
BEACH HAZARDS
TWO LONG PERIOD (>16 SECONDS) WESTERLY SWELL GROUPS
WILL SPREAD INTO THE COASTAL WATERS THIS WEEKEND. THE FIRST ONE
WILL ARRIVE ON SATURDAY WITH HEIGHTS BUILDING TO 4 TO 6 FT AT 17
SECONDS BY LATE AFTERNOON. A DECAYING WEST SWELL AROUND 6 FEET AT
11 SECONDS WILL ALSO BE PRESENT AND SHOULD MITIGATE THE SNEAKER
WAVE RISK. ANOTHER LONG PERIOD SWELL TRAIN IS FORECAST TO ARRIVE
ON SUNDAY WITH SIGNIFICANT SWELL HEIGHTS BUILDING TO 12 FEET WITH
PERIODS NEAR 16 SECONDS. BREAKERS UP TO 16 FEET FOR WEST AND
NORTHWEST FACING BEACHES ON SUNDAY ARE FORECAST BASED ON AVERAGE
BEACH SLOPE PROFILES. BEACHGOERS VENTURING NEAR THE SURF ZONE
SHOULD REMAIN VIGILANT. AVOID ROCKS, JETTIES AND STEEP BEACHES.
COASTAL FLOODING
CHANCE FOR MINOR HIGH TIDE FLOODING OF LOW-LYING
AREAS AROUND HUMBOLDT BAY WILL BE POSSIBLE SATURDAY AND AGAIN ON
SUNDAY. HIGHEST CHANCE (40%) FOR SALT WATER INUNDATION OF NORMALLY
DRY AREAS WILL BE ON SATURDAY, FOLLOWED BY SLIGHTLY LOWER CHANCES
OF 30% ON SUNDAY. IMPACTS ARE NOT EXPECTED TO BE AS SEVERE AS THE
KING TIDE FLOODING OBSERVED IN EARLY JANUARY. MORE NUISANCE ROAD
FLOODING IS LIKELY IN AREAS LIKE KING SALMON. STORM SURGE MODEL
HAS BEEN FLUCTUATING AROUND FROM 8.7 TO 8.9 FT MLLW FOR SATURDAY
AGAIN ON SUNDAY. STRONG SOUTHERLY WINDS (>35 KT) AND LARGE SURF
(>20 FEET) WILL MAKE COASTAL FLOODING MUCH MORE SIGNIFICANT WITH
GREATER IMPACTS. THAT COMPONENT OF THE STORM SURGE CONTINUES TO BE
LACKING AND THEREFORE IMPACTS WILL MOST LIKELY BE MINOR WITH ROAD
FLOODING IN KING SALMON. WE POSTED A GRAPHIC ON OUR WEB PAGE TO
CALL ATTENTION TO THIS.
EKA WATCHES/WARNINGS/ADVISORIES
CA...
COASTAL FLOOD ADVISORY FROM 8 AM TO NOON PST SATURDAY FOR
CAZ103.
NORTHWEST CALIFORNIA COASTAL WATERS...
SMALL CRAFT ADVISORY UNTIL 9 PM PST THIS EVENING FOR PZZ470.
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