Special Marine Warning 13, NWS Eureka, CA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
440 AM PST Mon Feb 19 2024

.SYNOPSIS...Showers and thunderstorms today will bring gusty winds
and locally heavy rain to the area through this evening. Showers
will continue on Tuesday with lighter winds and lighter rainfall.
Wednesday showers are expected to taper off and dry weather is
expected Thursday. Occasional light rain is possible Friday and
into the weekend.

&&

.DISCUSSION...Water vapor satellite shows a broad area of low
pressure off the coast this morning. Shortwaves continue to rotate
around this low bringing increased shower activity. The next one
is expected around mid morning and into the afternoon. There is
some notable instability with these showers. This will bring the
potential for thunderstorms. The models are showing 300 to 500
j/kg on Mendocino county with lower amounts farther north and
east. There is also around 40 kt of wind shear and the hodographs
have some curvature to them. This will bring the potential for
some stronger thunderstorms. The main threat with these storms
will be locally gusty winds. Gusts up to 60 mph are possible with
the strongest storms. In addition to the locally higher winds
around the showers and thunderstorms there will be winds of 50 to
70 mph on the ridges and exposed headlands. The high wind warning
and wind advisory remain in effect to highlight this. These
showers will also bring locally heavy rainfall and this could
create some minor flooding of low lying areas. Tonight and Tuesday
the upper level low off the coast slowly drifts north and fills.
This will allow winds to diminish and shower coverage to diminish.
There will likely be an uptick in shower coverage Tuesday
afternoon, but the overall wind field will be much lighter.

Occasional showers are expected to continue into Wednesday as the
low moves gradually off to the north. The showers will continue
to diminish in coverage and will mainly be in Humboldt and Del
Norte county. There may be an uptick in the afternoon over the
interior. Some of the areas may see fog in the morning if they
manage to clear out.

Wednesday night into Thursday high pressure starts to build in
and fog will likely be more widespread Thursday morning. Dry
conditions are expected Thursday and most areas may see clear
skies once any fog burns off. Friday and into the weekend the
ensemble clusters are generally showing an upper level low
approaching the central CA coast. Most of the clusters show NW CA
only seeing light rain, although one of the clusters does bring
some heavier rain to Mendocino and Lake counties. This highlights
some of the uncertainty in the models. MKK

&&

.AVIATION...MVFR to VFR conditions at the terminals are expected
early this morning as showers move across the area. Later this
morning into the afternoon stronger showers and thunderstorms will
move through the area, bringing gusty winds, lowering ceilings, and
visibility impacts during periods of heavy rain. MVFR and IFR
conditions across all terminals are expected as these showers move
through. Low level wind shear and gusty winds are forecast to remain
elevated at all terminals through Tuesday morning. Thunderstorm
chances will begin to taper off late tonight and into early Tuesday
morning, though rain showers will continue into late Tuesday
morning.

&&

.MARINE...Showers and thunderstorms tonight will increase in
intensity this morning and through the evening. Strong thunderstorms
with frequent lightning, hail, storm force gusts, and waterspouts
are possible. Widespread gale force southerlies will begin early
this morning, starting in the southern waters and spreading to the
northern waters as the low moves northward. A large, steep westerly
swell has begun to fill in and will peak this afternoon and combine
with steep southerly wind waves creating chaotic seas of up to 20
feet. Gale force winds will diminish by Tuesday afternoon, and seas
will gradually diminish to below 10 feet on Wednesday. Seas will
continue to be dominated by a series of relatively tame westerly
swells for the remainder of the week. Winds will remain light for
the remainder of the week.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Wind Advisory from 8 AM this morning to 4 AM PST Tuesday
     for CAZ101>103.

     Flood Watch through Tuesday morning for CAZ103>106-108>115.

     High Wind Warning until 4 AM PST Tuesday for CAZ104-114-115.

     High Wind Warning from 8 AM this morning to 4 AM PST
     Tuesday for CAZ105-106-108.

     Winter Storm Warning until 3 PM PST Tuesday for CAZ107.

     High Wind Warning until 10 PM PST this evening for
     CAZ109>113.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 9 AM PST this morning for PZZ450.

     Gale Warning from 9 AM this morning to 3 AM PST Tuesday for
     PZZ450.

     Small Craft Advisory until 3 AM PST early this morning for
     PZZ455-470.

     Gale Warning until 9 PM PST this evening for PZZ455.

     Gale Warning until 9 AM PST Tuesday for PZZ470.

     Gale Warning until 3 PM PST this afternoon for PZZ475.

&&

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