790
FXUS66 KEKA 272104
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
104 PM PST Thu Nov 27 2025

.SYNOPSIS...A weakening front may generate light showers tonight
through Friday morning, primarily for Del Norte and northern
Humboldt. Otherwise, dry and seasonably cool weather is forecast
for the next 7 days. A highly energetic long period west swell
will bring an increased risk for hazardous beach conditions Monday
through Tuesday next week.

&&

.DISCUSSION...Decaying frontal boundary trailing southwestward
from a surface low offshore the Pacific NW has been slowly
moving toward the North Coast this afternoon. So far only 0.01 to
0.04 inches of rain has occurred, mostly in Del Norte. High
resolution models continue to depict a shallow moist layer pushing
onshore this evening and overnight for perhaps additional light
rain on the order of a few hundredths in the Humboldt Bay area.
High resolution ensemble guidance indicates highest chances for
0.10 to 0.20 inches in 24 hours ending 4 AM Fri over Del Norte
County and coastal areas of northern Humboldt north of Trinidad.

Above normal 500mb heights will most likely (80% chance) keep much
of Northwest California in a long stretch of dry weather all next
week.

There are a couple of caveats for light spotty precip, however.
A trailing trough and surface low south of 40N will approach 130W
on Fri, and then drift southward through the day. All models keep
this low too far offshore for precip concerns. Another shortwave
trough will swoop down across the Pacific NW into the Great Basin
over the weekend. This trough has an overland trajectory and will
most likely serve to reinforce the dry offshore flow across our
forecast area. Overnight frost and freezing morning temperatures
will once again be prime concern for those with sensitive plants.

A third shortwave trough may (10% chance) generate fleeting
showers for Del Norte and mountains of Trinity Mon or Tue. This
second insider slider trough will carve out a larger scale trough
that will promote blustery N and NE winds around mid week. With
lower dew points, calm winds in the valleys, clear skies and long
nights, the threat for frost or freezing temperatures will once
again crop up. A killing freeze has already occurred multiple
times in Trinity, northern interior Mendocino and northern Lake
Counties. We have suspended issuing frost and freeze products for
these areas until spring. Cold weather products for wind chill may
be necessary if an unseasonably cold air mass settles over the
area around mid next week. There are subtle signs of omega block
break down or a westward shift in the longwave the following
weekend of Dec 6-7 and consequential precip will be possible.

&&

.AVIATION...(18Z TAFS)...General overcast skies will continue to
move through the region as a dry weak front progresses east. Chances
for light rain will diminish greatly by late this evening for
coastal terminals in northern Humboldt and Del Norte counties. MVFR
ceilings will continue for coastal terminals through this TAF period
with ceilings approaching IFR conditions overnight and into early
Friday morning. General cloudiness will continue into late Friday
morning. /JLW

&&

.MARINE...Winds are shifting northerly this afternoon in the wake of
the passing front. Northerlies will increase into Friday, especially
in the southern waters. Models support that the strongest winds will
be south of Cape Mendocino, with potential gusts up to 20 kts. For
the weekend, northerly winds are anticipated to expand northward
with gusts to 25 kts across the outer waters by Sunday.

A forerunner mid-period WNW swell around 8 to 12 feet at 11 to 12
seconds will continue to build in this afternoon/evening. Wind waves
around 6 to 9 feet at 8 seconds expected on Sunday.

&&

.BEACH HAZARDS...A highly energetic long period westerly swell
group generated from a Hurricane Force low pressure system near
the international dateline (180th meridian) will arrive Sunday
night and build through the day on Monday. This high energy swell
will bring a high risk for sneaker waves to Northwest California
beaches on Monday. The sneaker wave risk will probably persist
Monday night and Tuesday, though should decay to moderate levels
as swell heights increase to 10 feet or more. Pay attention and
stay above the high water line and any wet sand to stay safe. If
the ground is wet, waves have surged there recently. Stay safe and
never turn your back on the ocean! /ZVS

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 3 PM this afternoon to 9 AM PST
     Friday for PZZ450-470.

     Small Craft Advisory from 11 PM this evening to 9 AM PST
     Friday 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.

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