554
FXUS66 KEKA 191324
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
524 AM PST Sun Jan 19 2025

.SYNOPSIS...Continued dry through Thursday, with some precipitation
potential toward Friday next week and into the following weekend.
Chilly nights and mornings with areas of frost and patchy fog into
mid-week next week. Potential for gusty winds exists for Lake County
Monday. Potential for gusty winds return for much of the entire area
Friday and Saturday.

&&

.DISCUSSION...

Key Messages:

Gusty winds for Lake County Monday and Monday evening, and for the
rest of the area Friday and Saturday. Frost potential (including the
coast) through at least Wednesday morning next week. Dry weather
through Thursday next week. Fog potential for coast and interior
valleys through at least Wednesday morning next week.

Weather Pattern Overview:

Upper level ridge over the eastern Pacific ejects a couple of
shortwave ridges for early to mid week to ensure dry weather through
Thursday. A consistently forecast trough is still forecast from
ensembles to encroach the easter edge of the eastern Pacific omega
block high and shoe horn into the western United States for a few
days, giving the potential for gusty winds and light precipitation
for Friday into the weekend. Coastal stratus potential does still
exist through mid-week, but perhaps will keep off shore during the
night for much of the time from night time east winds.

Forecast Confidence and Deviations:

Omega block upper level ridge continues as the dominating feature
influencing our weather heading into early to mid week. The eastern
edge of the ridge will give way to a potent positively tilted trough
shoe horn its way into the western United States as it digs and
becomes more amplified. Confidence is high for a dry forecast
through Thursday, essentially all ensembles pointing toward a ridge-
dominated scenario. Strong winds aloft have potential to mix down
for some gusty winds in Lake County for Monday and Monday evening,
with northeast winds of 20 to 30 mph gusting up to 50 mph. Look for
some gusty winds to return Friday and Saturday for much of the rest
of the entire area. We stand a 50-60% chance of hitting gusts
greater than 45 mph along the coast from Eureka to Crescent City on
Friday. And a 50% chance of wind gusts greater than 45 mph on
Saturday for Clearlake in Lake County. Any rain amounts appear to be
rather light for Thursday night through Saturday.

Although frost potential exists for coastal areas through mid-week,
with some freeze potential (generally 5-20% for lows below 32). This
will largely depend on how long clear skies take hold and how much
off shore flow we get along the coast.

The NBM is still indicating a shot a rainfall total of greater than
0.05 for Friday into the weekend, but has backed off a bit from the
previous morning run yesterday. The chance of receiving at least a
total of 0.05 inches of precipitation during the 3-day period from
Friday through Sunday night runs from about 20% chance in Lake,
Mendocino, and Trinity Counties, to about 40% chance over the
Humboldt Bay area, to about 50% for Del Norte County. /MH

&&

.AVIATION...Stratus is in place along much of the coast and many of
the near coastal river valleys. KCEC remains clear at this point,
but there is some stratus very nearby that could easily move in
briefly this morning. Skies are expected clear at some point today
with an inside slider moving down the east side of the ridge will
bring stronger offshore flow and dry air tonight. The uncertainty
lies in the timing of when the skies clear out. The HREF at ACV has
a 30 percent probability of a ceiling below 1,000 feet in the
evening dropping to zero overnight. It is often difficult for
stratus to clear out overnight, but this offshore flow may be strong
enough. UKI is expected to remain clear with light winds. MKK

&&

.MARINE...The fresh northerly winds have started to push closer to
the coast this morning, but remain less than 10 kt at the buoys.
Later today a weather system moving by to the east of the area will
bring some stronger northerly winds to the waters. These are
expected to peak around 15 to 25 kt this evening. These winds and
the stronger winds to the north of the area are generating a fresh
swell of 6 to 10 feet at 8 seconds or so. This is expected to remain
beyond 10 NM from shore with the largest waves to the north. So have
added a small craft advisory for the winds and waves in zone 470
and mainly the waves in zone 475.

In additions to the winds there is a 20 seconds swell at 8 feet
moving through the waters. The buoys are showing some set behavior
in these waves. This will create a risk for intermittent larger
waves breaking in the shallow areas or shoals.

Monday the winds are expected to diminish in the morning with 5 to
10 kt winds in the afternoon. These are expected to continue into
Tuesday. The long period swell is expected to be down to around 6
feet at 14 seconds. Wednesday there is decent agreement in the
models that the winds will start to increase again, around 15 to 20
kt by the afternoon. These winds are expected to continue to
increase late in the week with gales possible on Friday and
Saturday. MKK

&&

.BEACH HAZARDS...he long period swell is currently around 8 feet at
20 seconds bringing breakers of around 15 feet. The buoys are
indicating some fairly significant set behavior with 10 to 15
minutes between some of the larger sets. This is likely creating
some sneaker waves. The beach hazard statement looks to be on
track.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Beach Hazards Statement through Monday afternoon for CAZ101-
     103-104-109.

     Wind Advisory from 4 AM to 10 PM PST Monday for CAZ114-115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory from 11 AM this morning to 3 PM PST
     Monday for PZZ470.

     Small Craft Advisory from 3 PM this afternoon to 3 PM PST
     Monday for PZZ475.

&&

$$

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