Frost Advisory 9, NWS Eureka, CA

189 
WWUS76 KEKA 041600
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
900 AM PDT Sat Apr 4 2026

CAZ110-111-114-041700-
/O.EXP.KEKA.FR.Y.0009.000000T0000Z-260404T1600Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
Northern Lake-
Including Covelo, Potter Valley, and Gravelly Valley Airport
900 AM PDT Sat Apr 4 2026

...FROST ADVISORY HAS EXPIRED...

The threat has ended.

$$

For hazard areas see https://www.wrh.noaa.gov/map/?wfo=eka

DB

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
151 AM PDT Fri Apr 3 2026

.SYNOPSIS...Much warmer and drier than normal conditions will build
today and through the weekend. Cooler conditions return next week
with chance for wetting rain mid week.

&&

.KEY MESSAGES...

-Frost potential through early Friday morning.

-Interior highs int he low 80s this weekend

-Slight chance of wetting rain mid next week.

&&

.DISCUSSION...A ridge of high pressure has rapidly begun to build.
Clear skies and much drier air settling over the areas has allowed
for relatively cold temperatures overnight with many interior valleys
in the upper 30s by midnight. Patchy frost formation is likely by
sunrise, though sporadic valley fog will limit overall coverage.

Solidly warmer than normal conditions will arrive Friday. Warming
will peak this weekend with interior high temperatures in the low to
mid 80s. Potential for highs over 85, however, is generally low
(around 15% chance for the hottest valleys). Marine air will be
restricted to a shallow marine layer at the coast, especially after
moderate north winds along shore on Friday give way to nearly calm
winds this weekend.

There is high confidence that high pressure will gradually weaken by
early next week with a low pressure system moving in along shore.
The path, strength, and moisture associated with this low remains
highly variable, though chances have slightly improved compared to
yesterday. About 40% of model ensemble members suggest wetting rain
across the northern half of the area, though still less than 10%
show potential for any amount over 1.0 inch.
/JHW

&&

.AVIATION...Prevailing VFR conditions is expected
for all TAF sites through the period. Surface winds from N-NE up to
5 kts, becoming to the NW at 10-15kts with occasional higher gusts
Friday afternoon. /ZVS

&&

.MARINE...A very steep and hazardous westerly swell will start build
in overnight, reaching 10-15 feet at 12 seconds early Thursday. A
Hazardous Seas Warning remain in effect through Thursday afternoon
for the northern waters, while small crafts advisory for the
southern waters. Large westerly swells will gradually subside
Thursday night through Friday night, with hazardous conditions for
small crafts across all waters. Winds and seas will ease over the
weekend, and persist through early next week. /ZVS

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Frost Advisory until 9 AM PDT this morning for CAZ102>106-
     109>115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 6 AM PDT Saturday for PZZ450-455.

     Small Craft Advisory until 11 AM PDT Saturday 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

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For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png