785
FXUS66 KEKA 141122
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
422 AM PDT Wed May 14 2025

.SYNOPSIS...Drying and warming trend today through the remainder
of the week. Breezy northwest winds is anticipated each afternoon.
A weather system will bring cooler temperatures, gusty winds and a
slight chance of rain Saturday. Windy conditions continue Sunday
with warmer temperatures next week.


&&

.DISCUSSION...High pressure continues building into the West
Coast. This is promoting surface north-northeast winds, with some
breezy winds over the higher terrain observed. Areas of fog and
patchy dense fog have developed overnight along the shelter
valleys with clear skies and strong radiational cooling. High dew
point values in the upper 30`s to mid 40`s are precluding frost
conditions across the interior valleys in Trinity and Mendocino
counties keeping low temperatures in the upper 30`s to mid 40`s.

Drying and warming trend will continue today through Friday
across Northwest California, but weak shortwaves low will drive
down across the eastern periphery of the ridge. This will bring
periods of increasing mid to high level clouds across the area.
Inland high temperatures are forecast to be in the 70`s, with the
warmest days Thursday and Friday. Although, highs warming up into
the low 80`s are expected are expected across the warmest
interior valleys. Coastal areas will remain seasonably with highs
in the upper 50`s into low 60`s. Winds are expected to breezy each
afternoon along the coast, but nothing particularly notable.

Friday night into Saturday, an upper level trough and associated
weak cold front drop down from western Canada. This will bring an
increasing chance (25-50%) of precipitation across the northern
portion of the forecast area, especially for Del Norte. Rain
forecast amounts remain light, with showers mostly over the
interior and perhaps a push of marine moisture and low clouds.
NBM probabilities of 24hr precipitation of 0.10 in or greater
from 25-35% in Del Norte. Otherwise, dry weather with near or
below normal high temperatures in the interior is the most likely
outcome for this weekend. Winds are expected to strengthen behind
this weather system and the ECMWF is highlighting notable winds.
This is expected to increase fire danger, but this will depend on
how low the RH remains.

Next week high temperatures are expected to warm and the inland
areas may see some of the warmest temperatures so far this season.
The NBM is showing a 30 to 40 percent chance of Ukiah reaching 100
degrees late next week./ZVS


&&

.AVIATION...Early Wednesday morning conditions are MVFR with TEMPO
movement into IFR. Chances for IFR will greatly reduce later this
morning. As was seen yesterday, an onshore wind push will coral some
stratus inland around Humboldt Bay along the higher terrain. This
will present opportunity for TEMPO MVFR CIGS into the afternoon at
ACV. Full scattering is then likely. Northerly winds will become
breezy, with gusts of 25 to 30 kts expected at the coastal terminals
this afternoon. As winds ease this evening, the stratus will expand
once again around Humboldt Bay, through ACV and likely into CEC with
highly localized southerly return winds. CIGS will initially
continue MVFR with dips to IFR possible. A ridge will nose in from
the west as a trough exits east. This setup will favor better
chances for IFR to maybe LIFR CIGS going into Thursday morning with
a compressing inversion. Currently probabilities are on the lower
end for IFR (30%), and lower for LIFR (18%), but these may trend
higher. JJW


&&

.MARINE...As a trough slowly departs east, high pressure ridging
will nose in to the region from the west. As a result, the northerly
winds will trend stronger through Thursday. Advisory level winds up
to 25 kts, with higher gusts, can be expected in the northerly zones
through Thursday afternoon. Winds will particularly be accelerated
around Cape Mendocino from the expansion fan. Northerly winds up to
30 kts, with higher gusts are now forecast through close to half of
zone 475 and 455. This magnitude of winds has warranted Gale Watches
from Thursday afternoon through Thursday night when the strongest
winds are forecast. The fading, mid period NW swell pulsed higher
and the ongoing Small Craft Advisories have been expanded into the
Northern Inner zone 450 to cover the steep waves and anticipated
strengthening northerly winds.

A weak shortwave trough will dive south through the region on
Friday. This will temporarily weaken the northerly winds on Friday,
but winds of over 20 kts will remain south of the cape. Northerly
winds will quickly snap back stronger Saturday behind the trough.
Gale Warning criteria may once again be met in the southern waters
south of the cape if coverage is high enough, particularly Sunday
afternoon. JJW


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Frost Advisory until 9 AM PDT this morning for CAZ107-108-
     110-111-114.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 9 PM PDT Thursday for PZZ450-470.

     Small Craft Advisory until 3 PM PDT Thursday for PZZ455-475.

     Gale Watch from Thursday afternoon through Thursday evening
     for PZZ455-475.

&&

$$

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