Island Mountain, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

313
FXUS66 KEKA 260702
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1202 AM PDT Thu Mar 26 2026

.SYNOPSIS...Breezy to strong north and northeast winds are expected
through Thursday night. Dry conditions with above normal high
temperatures are expected for the interior through the weekend.
Potential for significant precipitation will return next week.


&&

.DISCUSSION...Colder weather conditions are expected into early
Thursday under a slightly cooler air mass and drying offshore flow.
Frost advisories have been issued for the valleys of Mendocino
County and to a lesser extent (areal coverage wise) northern Lake.
Coastal areas are not as certain with low cloud cover and gusty
winds hindering the longwave cooling through the night. Offshore
winds and increasing subsidence should result in lower dewpoints
through the night and pockets for frost will be possible (50%
chance). Interior portions of Humboldt and Del Norte are 6 days from
the start of the growing season (Apr 1) while Trinity County is 21
days away (Apr 15). That is why frost/freeze products have not been
issued for these Counties. Now looking at apparent temperatures for
SW Humboldt, it does look to satisfy criteria for a cold weather
advisory with wind chills less than 30F and strong northerly winds
(gusts > 40 mph) over mostly the higher terrain.

Otherwise, dry and stable weather is expected for the remainder of
this week into the weekend. Generally above normal high temperatures
and areas of minor heat risk are forecast for mostly the interior as
a broad flat ridge aloft dominates. The warmest locations will
continue to be in Lake, Trinity and interior Mendocino Counties
where max temps are projected to peak into the upper 70s to mid 80s
Thu and Fri. This is still 10-15F above late March averages.
Overnight lows will remain seasonably chilly with perhaps some
valley sites cooling into the lower to mid 30`s. Overnight
temperatures will remain elevated in the 50s and 60s in the thermal
belts and over the high ridges where breezy E-NE winds persist
through the night. No huge changes are anticipated at this time this
weekend with above normal daytime highs likely continuing Sat and
Sun. Coastal stratus may return this weekend and increase as the
offshore wind abate.

Longer range models and national blend of models continue to trend
wetter and colder next week, Monday March 30 to Friday, April 3rd.
Higher end scenario (90th percentile) suggests multiple inches of
rain (> 2 to 5 inches) spread out over 3-days while a lower end
scenario (10th percentile) would yield an inch or less over the same
3-days. There are many unknowns like how much rain over what time
interval and the duration. This far out it is hard to pin point, but
there are signs in the model data. Snow levels will eventually fall
by mid week too. How quickly and how low remains to be seen as well.
If the cold core aloft dips far enough south we could definitely see
some low top thunderstorms and small hail. March is usually the max
on average for small hail. This is the first promising sign for
significantly cooler and wetter weather I have seen in quite
sometime. We will continue to message these hazards via weather
story posts to give folks as much heads up as possible. You may
think summer has arrived early this year considering how warm and
dry it has been lately. However, the wet season is not over just
yet. Stay tuned for more details.


&&

.AVIATION...Gusty north winds will continue through the TAF period
with the gustiest winds along the coast, at coastal headlands, and
exposed ridges. Despite fresh moisture, north wind will most likely
keep conditions too mixed to form low fog or clouds with a less than
10% chance of any IFR conditions; however, periodic MVFR ceilings
could occur at terminals around Humboldt Bay. Mainly VFR
conditions will persist.


&&

.MARINE...North winds will continue to increase to gale force
conditions in the outer waters by very early this morning. Slightly
weaker, near gale conditions are likely in the inner waters.
Similarly strong winds will continue until early Friday with
gradually weakening north winds into the weekend.

Short period seas will rapidly build alongside the winds with steep
waves over 15 feet in the outer waters during the day today. Despite
mostly sub-gale winds in the inner waters, still strong winds
combined with wave energy from the outer waters will still create
steep, hazardous short period seas over 10 feet. Steep seas will
begin to fall alongside weakening winds Friday. /JHW


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Frost Advisory from 4 AM to 8 AM PDT this morning for
     CAZ101-103.

     Cold Weather Advisory until 9 AM PDT this morning for
     CAZ104.

     Frost Advisory until 9 AM PDT this morning for CAZ109>115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Hazardous Seas Warning until 6 AM PDT Friday for PZZ450-455.

     Gale Warning until 6 AM PDT Friday 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