147
FXUS66 KEKA 102049
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1249 PM PST Mon Nov 10 2025

.SYNOPSIS...Above normal temperatures and dry conditions will
persist through Tuesday with overnight valley and coastal fog. Wet
and unsettled weather conditions will impact the area starting mid
to late in the day on Wednesday. This will bring heavy rain and wind
Wednesday night. Thursday, snow levels are expected to drop as
low as 4,000 feet with potential additional precipitation.

&&

.DISCUSSION...High pressure persists over the area this afternoon
and is bringing very similar conditions to the last several days.
Low clouds and fog are continuing each morning, although the area
is a bit more limited and some valleys in southern Mendocino and
southern Lake counties are remaining clear. Afternoon highs
continue to be in the 60s to low 70s and again have kept them
below the NBM for today and Tuesday.

Early Wednesday the next weather system starts to approach the
area. This will start to increase southerly wind early in the
morning, first on the ridges and then to lower elevations along
the coast. These winds are expected to peak in the evening just
ahead of the wind. 925 mb winds are around 70 kt off the coast on
the GFS. The is some support for this in the ensemble clusters,
but still some big variability between clusters. The ECMWF EFI is
also highlighting the significant winds, but showing a shift of
tails near 1 indicating potential variability on the outcome.
Currently it looks like most areas will see wind gusts of 30 to 50
mph with the higher winds over the higher terrain and along the
coast. Currently it looks like a wind advisory may be needed for
portions of Del Norte, Humboldt, Mendocino and Lake counties. The
rain is expected to start in the early afternoon on the south
slopes and along the Mendocino coast. Farther north onset of the
rain is expected to be a bit later, especially north of Cape
Mendocino. The Humboldt bay area may be delayed even more,
possibly until late evening, due to the downsloping from the King
Range. Most areas are expected to see one to 2 inches of rain with
local amounts upwards of three inches Wednesday night and early
Thursday morning. Some flooding is possible in small streams,
urban areas and poor drainage areas.

Thursday morning there may be a brief break in the rain behind the
front, but showers are expected to take over fairly quickly as the
upper level trough moves over the area. This trough is bringing
some of the coldest air so far this fall. Snow levels are expected
to fall as low as 3500 or 4000 feet by Thursday evening. Most of
the main highway passes are not expected to be impacted, but Hwy
3 at Scott Mountain summit has a 30 percent chance of seeing over
3 inches of snow. This colder air is also expected to generate
some instability and the potential for thunderstorms through the
day on Thursday. Some of these storms may also contain small hail.
Generally it is not expected to be cold enough to cause
widespread problems, but there could be some accumulations.

Friday the upper level trough starts to move out of the area and
high pressure quickly starts building back in. The isn`t very
good model agreement on this yet, but some models show some precip
developing in the coastal counties. Saturday is generally looking
drier, especially in the afternoon. Inland valleys may see chilly
temperatures, but fog is likely fog and this may keeping them from
dropping below freezing. Another system is expected to bring
additional rain to the area Sunday, although this looks weaker
than the earlier system. MKK

&&

.AVIATION...Ground fog is currently burning off giving way to VFR
conditions today. High pressure over the area leads to light,
terrain driven winds inland with the occasional afternoon gust,
whereas light to moderate northerlies will develop at coastal
terminals by this afternoon. High resolution model soundings, HREF
analysis, and TAFLAMP probabilities are confident in the marine
layer forming tonight for the North Coast. MVFR conditions this
evening (05-07Z) will evolve into LIFR ceilings and slight
potential for fog (<1/2SM visibilities) lasting through the early
morning before another VFR day dominates again Tuesday.

&&

.MARINE...As high pressure builds early this week, northerly winds
form. The strongest of these winds will be in the southern outer
waters downwind of Cape Mendocino. Wind speeds will build to 25-
30kts creating steep wind waves up to 6ft, spray, and widespread
white caps. The current models show these winds increasing
slightly later so have push the start of small craft advisory in
the southern outer waters back until 7PM. These winds begin to
weaken Tuesday morning as a low pressure system moves towards the
PacNW. Seas and winds will remain moderately calm as decaying wind
waves mix with a NW mid period swell.

The influence of this next storm system begins to be felt on
Wednesday morning with building southerlies. There is increasing
forecast confidence on Gale Force winds for the outer waters by
Wednesday evening into Thursday. In addition to hazardous winds,
steep wind waves are expected Wednesday night through Thursday
morning. More confidence on the exact timing and details of this
next storm will be available as we get closer and more model data
becomes available that far out. The biggest uncertainty lies in
the strength of the winds as the low pressure system moves through
the area. More likely than not, a Gale Watch will be hoisted for
this midweek event.

After the midweek storm, a large NW swell will fill into the waters
on Thursday. Winds are to remain light to moderate through the week.
There is building confidence on another storm arriving late
this coming weekend into early next week.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 7 PM this afternoon to 10 AM PST
     Tuesday for PZZ475.

&&

$$

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