Frost Advisory 11, NWS Eureka, CA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1218 AM PDT Mon Apr 13 2026

.SYNOPSIS...Near to slightly below normal temperatures today with
clearing skies. Chilly temperatures likely again tonight. Rain
likely returns by Wednesday. Near freezing or freezing low
temperatures are expected late in the week with more rain possible
over the weekend.

&&

.DISCUSSION...The low pressure is moving out of the area and high
pressure has started to build in. Models have backed off the rain
on Monday morning and now just a trace to a few hundredths are
expected in Del Norte County and coastal Humboldt. Clear skies are
generally expected, although it looks like some of higher terrain
in the north may see lingering clouds. Tuesday morning there is
the potential for more frost. It looks more likely than Monday
morning with less clouds expected in Mendocino and Lake counties.
Tuesday afternoon temperatures are expected to be a few degrees
warmer than Monday, but remain in the 50s at the coast and the 60s
inland.

Tuesday night and Wednesday and upper low moving into Washington
is expected drag a front across northern CA and bring some rain.
This is mainly expected to impact Del Norte and Humboldt counties.
Rainfall amounts have continued to trend upwards in the models for
this storm. The current NBM is showing rainfall amounts around an
inch for Crescent City and Del Norte, but rapidly diminish as the
front moves south and weakens. Around a half inch is expected in
Eureka, a quarter inch in Weaverville and northern Mendocino
county. Less than a tenth of an inch is expected in southern
Mendocino and Lake counties. As usual the mountains will see more
than the valleys. Snow levels are expected to be over 5,000 feet
for most of the precip, but may drop below 4,000 feet as the
precip comes to an end Wednesday evening.

Wednesday night into Thursday morning has the potential to be an
unseasonably cold morning. The NBM is showing lows in the 20s in
northern Lake, northeast Mendocino, and much of Trinity county.
While this is certainly possible, fog and low clouds may develop
in some of the valleys to limit the radiational cooling. Thursday
afternoon clear skies and dry conditions are expected with highs
warming back into the 60s. This will likely set up Thursday night
to be the coldest night with lows in the upper 20s to upper 30s
across the area. Even the coast may see frost with some weak
offshore flow. Friday and Saturday afternoon highs are expected to
warm into the 70s and Saturday morning will likely not be as cold
as Friday morning.

Saturday night through Monday more rain is expected. At this
point the probability of over a half inch is less than a 35
percent for any particular 24 hour period. However much of the
area has a 20 to 50 percent chance of exceeding a half inch in 72
hours.

&&

.AVIATION...(06Z TAFs)...Mostly VFR conditions expected after
the last few days of intense weather. The cache of moisture on the
ground would normally raise concerns for ground fog development but
conditions do not look favorable for reduced visibility from
radiational cooling as clouds linger and some easterly flow is being
picked up by the models. Ceilings are likely to come down to around
1500 to 2500 feet at KACV and KCEC overnight but not bellow MVFR
thresholds. Northerly winds will build Tuesday afternoon, just below
20 knots. /EYS

&&

.MARINE...Unsettled weather marks the post low conditions over
near coastal and offshore area waters. After the passage of the
low, high pressure will fill in by Monday late morning as
northerlies build with 10 to 15 kt sustained winds and gusts up to
20 kts or more. Monday evening northerlies will further build to
around 20 kt sustained with 30kt gusts, particularly south of Cape
Mendocino. Tuesday, winds diminish in the northern outer waters
while shifting to a southerly bearing. Southern waters Tuesday
will have a NW bearing at a higher rate, especially in the coastal
waters in the lee of Cape Mendocino. Winds strengthen to fresh
breezes Tuesday night into Wednesday as a cold front approaches
from the North. This will be followed by strengthening northerly
winds Wednesday night through Friday as the pressure gradient
tightens. There is a high potential (85-100% probability) of gale
force gusts Thursday-Friday. /ZVS /EYS

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Winter Weather Advisory until 11 PM PDT this evening for
     CAZ107.

     Frost Advisory from 2 AM to 8 AM PDT Monday for CAZ110-111-
     114-115.

NORTHWEST CALIFORNIA COASTAL WATERS...
None.
&&

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