412
FXUS66 KEKA 151845
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1145 AM PDT Wed Oct 15 2025

.SYNOPSIS...Cooler and cloudier conditions start to ease by
Thursday, with sunny, dry, and slightly warmer weather forecast
through Saturday. A quick moving chance of rain is possible again
Sunday.


&&

.DISCUSSION...Satellite imagery late this morning is showing cloud
cover for much of the interior and interior valleys. This will
likely slowly clear out through the day today into Thursday.
Currently, cloud cover looks too widespread and observed dewpoints
too high to support widespread frost tonight. NBM is hinting at a
low chance for frost at Hayfork (20% chance), but this would need
both skies to clear and valley fog to not form.

Otherwise, high pressure is building into the area late this week
into Saturday, which will bring gradually warming and drying
conditions. Northerly breezes and the lower sun angle are unlikely
to warm interior valleys significantly, especially those that are
now shaded for most of the day, but generally 70s are forecast for
most valleys. The dry airmass and offshore flow may keep skies clear
over the coastal areas. These generally lead to chillier nights,
perhaps into the low to mid 40s. North winds in the afternoon are
likely to keep the temperatures from getting too high, with low to
mid 60s forecast Thursday and Friday. Chilly low temperatures are
possible again in the interior Thursday night into Friday morning
with less moisture and clearing skies. Frost is not out of the
question in the valleys of Trinity County, but confidence currently
remains low.

A trough begins to dip down into the Pacific Northwest Sunday,
bringing the chance for a quick dose of rain to the northern half of
the area. The chance for wetting rain (>0.1 inches) is about 30% or
higher north of Cape Mendocino, and around 60% in Del Norte. The
chance for a half inch of rain is only 30% in Del Norte, so impacts
are expected to be minor from this system. Southerly gusts of 25-30
mph or higher are briefly possible along exposed ridges and coastal
headlands. Showers following the main frontal passage could promote
an isolated thunderstorm threat offshore and around Crescent City
Sunday afternoon and evening.

Ensemble members are showing the potential for a stronger system
approaching the area mid to late next week. CPC is highlighting
northwest California for above normal rainfall in the day 8-14
outlook. There is a lot of variability in timing and potential
impacts at this time. The higher end of the scenario would involve
multiple days of rain, mountain snow, and gusty south winds. Stay
tuned. JB


&&

.AVIATION...The weather system to the south of the area brought
widespread stratus to inland and coastal areas today. This has
generally cleared at the coast and is clearing out across the
interior. Tonight stratus is expected to return. The coastal areas
may drop into IFR, but lower conditions are not expected. The inland
areas will likely see low clouds in the valleys with some fog at
cloud level above the valleys. Thursday is expected to see clearing
skies and breezy northerly winds in the afternoon. Gusts to 25 kt
are possible late in the afternoon.


&&

.MARINE...Southerly winds in place this afternoon near the coast and
out 10 to 20 miles. Some of these winds may be briefly around 15 kt.
The long period swell continues around 3 feet at 15 seconds. The
second northwest swell continues to be around 5 feet at 8 seconds.

Tonight into Thursday northerly winds return. These winds are
expected to peak on Thursday night or Friday morning and then
diminish through the day on Saturday. Models are coming into better
agreement on period of sustained 25 to 30 kt winds in the portions
of the outer waters Thursday. This will likely bring gusts to 35 kt
so have added a gale watch to highlight this Thursday night. This
may need to be extended into Friday, but the hi-resolutions models
don`t go out that far yet. A larger northwest wave is expected to
build in on Friday evening. This is expected to peak on Friday
around 9 feet at 15 seconds. This may bring a small sneaker wave
threat, although this mainly be Friday night. Saturday night into
Sunday morning there may be some brief southerly winds as a cold
front swings through. The strength and timing remain uncertain, but
most models keep the winds below 20 kt. Northerly winds are expected
to quickly return Sunday afternoon or overnight. These are expected
to increase to near gales or gales at some point on Monday. MKK


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 4 PM Thursday to 4 AM PDT
     Saturday for PZZ450-455.

     Small Craft Advisory from 11 AM to 4 PM PDT Thursday for
     PZZ470-475.

     Gale Watch from Thursday afternoon through late Thursday
     night 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.

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