577
FXUS66 KEKA 102314
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
314 PM PST Wed Dec 10 2025

.SYNOPSIS...Generally dry weather and above seasonably temperatures
through this weekend, especially across the interior. Moderate
risk of sneaker waves along NW California beaches on Thursday.
Wet weather conditions returns early to mid next week.


&&

.DISCUSSION...Persistent high pressure over the Pacific continues
to promote generally dry weather and above-seasonal temperatures
across NW California, especially across the interior. Stratus and
fog have been stubborn to lift and scatter out this afternoon
along the North Coast, while some interior valleys in Humboldt and
Trinity counties continue to slowly clear out. Elsewhere, sunny
to partly cloudy sky conditions are observed. Afternoon
temperatures have been running generally 5 to 10 degrees warmer
compared with Tuesday`s reading, with highs in the mid-60s to
mid-70s across the interior with sunny skies. As of 1 PM, the ASOS
at the Ukiah Municipality Airport reported 70F. The forecast calls
for 74F at Ukiah, which would break the daily high temperature
record for today`s date of 73F set back in 1958.

This evening into Thursday, areas of fog and patchy dense fog are
expected to redevelop again, especially along the North Coast and
some interior valleys in Humboldt and Trinity counties. Overnight
temperatures are forecast to be generally in the 40s, but in the
low to mid 30s for the coldest valleys in Trinity, interior
Mendocino and Lake counties.

Ridging remains dominant and strengthening off the West Coast
Thursday and Friday, continuing to promote dry weather and
warming trend pattern. High temperatures will remain 10-20F above
the seasonal average. The offshore flow regimen (easterly winds)
is anticipated to increase Thursday night into Friday, keeping
the air dry and reinforce the warming trend. NBM probability for
high temperatures exceeding 75F around Ukiah shows a 45% on
Thursday and increases to 55% on Friday. See Climate section
below. Even the coastal areas are expected to warm up to mid 60s
on Friday, before seas breezes develop.

Over the weekend, the ridge begin to show signs of weakening and
shift eastward, but confidence remain high in continuing dry
weather through the weekend and into Monday next week.
Temperatures will see a minor fluctuations, generally remaining
above normal for this time of year.

Heading to next week, high pressure breakdown and shift eastward,
while an upper level trough develop over the Gulf of Alaska.
A series of shortwave and frontal system embedded to the trough
moving north of the area will bring increasing chance of
precipitation early to mid next week. Ensemble and operational
models are in a better agreement with wet weather conditions
returning as early as Monday for the northern portion of the
forecast area, with increasing chance of precipitation for
Mendocino and Lake counties Monday night/Tuesday. Light rainfall
is most likely expected with the frontal system moving across the
area Monday into Tuesday. Stay tuned! /ZVS



&&

.AVIATION...Coastal terminals remain entrenched in low flight
categories this afternoon. At KCEC, while visibility has improved to
VFR, the airfield remains in LIFR conditions due to a persistent low
ceiling (BKN004). KACV is even more restricted, remaining socked in
with LIFR vertical visibility (VV002) well into the afternoon.
The latest LAMP guidance is capturing this persistence well,
particularly for KACV where it forecasts LIFR visibility (< 1/2 SM)
to prevail through the end of the current TAF cycle at 18Z Thursday.
Given the failure of the stratus to break today, the forecast leans
heavily on this pessimistic LAMP solution, keeping KACV in LIFR
conditions with little opportunity for improvement through Thursday
morning.

For KCEC, both 1-D viewer data and LAMP guidance indicate the
current VFR visibility will be temporary. Probabilities for dense
fog ramp up sharply this evening (60% chance of less than one mile
visibility), with the LAMP specifically targeting 05Z for a return
to 1/4 SM visibility and vertical visibility below 200 feet.
However, guidance suggests this fog layer may be unstable; while the
prevailing forecast calls for LIFR conditions through 10Z, the
conditional visibility guidance hints at fluctuations in visibility
categories overnight before scattering out by around 17Z-18Z.

In the interior, KUKI remains VFR under clear skies with high
pressure in control. While NBM probabilities for fog are generally
low, the LAMP guidance flags a brief window of potential MVFR
visibility due to mist between 13Z and 17Z tomorrow morning. A TEMPO
group has been included in the KUKI TAF to account for this
possibility, though VFR will likely dominate the period. Winds
remain light and terrain-driven at all terminals. /MH


&&

.MARINE...Buoy observations early this afternoon highlight a sharp
contrast in conditions north and south of Cape Mendocino. To the
north, the St. George buoy (46027) is reporting light and variable
winds around 2 to 4 knots. Conversely, the Point Arena station is
already verifying the forecast trend, showing northerly gusts
increasing to near 20 knots. This supports the start of the Small
Craft Advisory for the southern zones (PZZ455/475) effective at 3 PM
today. While the northern waters are seeing a reprieve today, this
will be short-lived.

The pressure gradient is forecast to tighten tomorrow (Thursday),
causing northerly winds to increase across the northern zones as
well. While speeds may not immediately reach advisory criteria
during the day Thursday, the building trend is clear. By late
Thursday night into Friday morning, these strengthening winds will
likely generate sufficiently steep seas to warrant a Small Craft
Advisory for the northern outer waters (PZZ470). The probability of
wind gusts reaching greater than 34 KTS for the southern outer zones
for Thursday is 50-80% for about half of the southern outer zone,
however overall, sea state is what is driving most of the small
craft advisories.

Throughout the region, the sea state remains dominated by a mid-
period westerly swell (around 13-14 seconds). South of the Cape,
these swells are combining with steep, fresh wind waves to create
hazardous combined seas of 9 to 11 feet. Conditions are expected to
improve across all zones by the weekend as the high pressure ridge
weakens and the flow turns southerly. /MH


&&

.BEACH HAZARDS...A Beach Hazard Statement is in effect from
Thursday morning through Thursday evening due to a moderate risk
of sneaker waves along areas beaches. A mid-period westerly swell
will build across the coastal waters tonight/early Thursday, with
heights at 8-9 feet at 14 seconds. These high energy will bring a
moerate risk of senaker waves on Thursday, resulting in the
potential deadly waves that unexpectedly surge much farther up the
beach than previous waves, overtaking unaware beachgoers. Remember
to never turn your back to the ocean, and to avoid steep beaches,
jetties, outcroppings, and rocks during these events./ZVS


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Beach Hazards Statement from Thursday morning through
     Thursday evening for CAZ101-103-104-109.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 10 AM PST Thursday for PZZ455.

     Small Craft Advisory from 3 AM to 3 PM PST Friday for
     PZZ470.

     Small Craft Advisory until 3 PM PST Friday 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