Alton, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

114
FXUS66 KEKA 042245
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
245 PM PST Sat Jan 4 2025

.SYNOPSIS...Intermittent light rain is expected through early
Monday in Del Norte and Humboldt. Areas farther south and east
will see mainly dry conditions. Dry weather and warmer
temperatures are expected starting on Tuesday and lasting through
much of the upcoming week.

&&

.DISCUSSION...High pressure is attempting to build into Northwest
California this afternoon, but weather systems keep moving over
the top of the ridge and into the Pacific Northwest. So while the
bulk of the rain is now well north of the area, areas from
northern Mendocino county and northward will continue to see
clouds. Humboldt and Del Norte counties are expected to see some
light showers as well. Late tonight and early Sunday Del Norte
county is expected to see0.25 to 0.50 inches of rain as a
shortwave moves by to the north. Further south only 0.10 to 0.25
inches are expected in northern Humboldt. Some continued light
rain is possible Sunday night with rain diminishing Monday
morning. These clouds and showers will keep temperatures in the
upper 40s to low 50s in these areas. Tonight fog is expected again
in the valleys of Mendocino county and possibly Lake county as
well. This may be dense in some areas and may persist into the
early afternoon on Sunday. This will keep temperatures cool in the
foggy areas as well. Fog is likely again Sunday night into Monday
in the valleys of Mendocino and Lake counties and farther north
where skies can clear.

Monday afternoon the ridge finally starts to gain some traction
and build over the area. This will clear out the high clouds and
models are indicating quite a bit of moisture around and fog
development. The winds also start to turn more offshore Monday
night. These look to strengthen over Mendocino and especially
county early Tuesday morning. The NAM is showing 925 mb winds of
30 to 35 kt over the ridges of eastern Lake county. This may need
a wind advisory with the NBM showing a 25 percent chance of
exceeding 45 mph. Tuesday morning this fog may take some time to
clear and keep the northern inland valleys cooler. Offshore flow
starts to set up and this will help clear skies out along the
coast. Tuesday night into Wednesday the high pressure continues to
build and the offshore flow strengthens. This should limit fog to
just the more protected valleys in the north and even these
should clear fairly quickly. The higher terrain is expected to see
fairly low RH Wednesday morning and possibly again Thursday
morning. High pressure and offshore flow is expected to persist
over the region through the work week. An upper level low moving
into southern CA could enhance the offshore flow. This could keep
cloud away from the coast and much of the area for the week. MKK

&&

.AVIATION...Rain showers have largely diminished today, though MVFR
ceilings persist at CEC this afternoon. Breezy southerly continue at
the coastal terminals, especially at CEC, overnight as another
system moves through. A LLWS threat is possible at CEC as well
Sunday morning. LIFR/IFR ceilings in the interior have persisted for
much of the day, but have finally begun to scatter out in UKI. Fog
and low ceilings are possible again tonight in UKI. MVFR ceilings
are expected for the coastal terminals and could persist into Monday
morning. JB

&&

.MARINE...Southerlies have picked up north of Cape Mendocino this
afternoon as a weak system approaches the area. Gusts of 20 to 25
kts are possible through Sunday morning before weakening. A westerly
swell has gradually decayed today, and significant wave heights are
around 10-14 ft. These will continue to trend downward, though steep
seas are possible along with the strongest winds. South of the Cape,
wave heights and winds are forecast to trend downward with light
southerly winds. High pressure fills in Monday into Tuesday,
bringing the return of elevated northerlies. Significant wave
heights are forecast to reach at least 10 ft again as a larger
westerly swell fills in Tuesday. JB

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 9 PM PST this evening for PZZ450-
     455-475.

     Small Craft Advisory until 9 AM PST Sunday for PZZ470.

&&

$$

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