384
FXUS66 KEKA 300756
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1256 AM PDT Wed Sep 30 2026

.KEY MESSAGES...

* High pressure builds through the rest of the week, bringing an
  extended dry period with interior valley high temperatures warming
  into the 80s and 90s.

* Northwest gusts are expected again Wednesday with gusts up to
  +30mph for the King Range and other exposed terrain and gusts up
  to 20-25mph for North Coast headlands.

&&

.SYNOPSIS...Upper-level ridging builds over the West Coast this
week. A warming trend is expected for inland areas with coastal
areas being more likely to have morning overcast or foggy
conditions.


&&

.DISCUSSION...The forecast are is being dominated by a Pacific high
pressure center off the coastline by the 140W longitude and a
developing thermal trough developing in the wake of Hurricane Polo.
This will lead to a more summer-like pattern as the week goes on.
Inland areas can expect warming through the end of the week with
inland valleys reaching the high 80s to low 90s. The Russian River
Valley even has around a 50% chance to reach >95F Thursday. North
Coast areas can expect overcast skies developing each evening with
areas of localized fog and drizzle. These are likely to scatter out
in the afternoons.

Another expected result of this summer-like pattern is gusty north
winds along the coast. Marine waters will remain hazardous due to
short-period waves caused by winds up to 35-40kts in the windiest
spots. Directly along the coastline and in river valleys close to
river mouths for Humboldt and Del Norte Co., expect breezy
afternoons. The King Range will receive the bulk of the winds with
gusts reaching up to 50kts on the exposed ridgetops as northerlies
flow over the E-W orientated topography. Inland areas are likely to
see gusts up to 15-20mph in the afternoons.

This weather pattern is expected to continue through the weekend
into next week as an dip in the jet stream remains far away from
the eastern Pacific Ocean. The GEFS and EPS ensemble models show
high pressure continue through the middle of next week. So expect
these warm and dry conditions to continue.


&&

.AVIATION...Coastal terminals are showing decreased visibilities and
low ceilings tonight due to coastal stratus. MVFR conditions with
periods of IFR and even LIFR are expected through dawn. Northerly
winds are expected to continue overnight into the afternoon with
clearing possible by 17Z (+/-1hr) for ACV. Inland terminals will see
afternoon gusts up to 15-20mph and VFR conditions. Terminals near
coastal river valleys can expect earlier clearing around 14Z.


&&

.MARINE...Fresh northerlies continue due to the pressure gradient
between offshore high pressure and the interior thermal trough.

* Northern Inner Waters: Northerlies of 10 to 20 kt will generate
  steep short-period seas. A west-northwest swell at 12 to 14
  seconds continues today. A Small Craft Advisory remains in effect
  through Thursday morning.

* Northern Outer Waters: Northerlies of 20 to 25 kt with gusts to 35
  kt (mainly in the lee of Cape Blanco) will build combined seas to
  10 to 11 ft. A Small Craft Advisory remains active through early
  Wednesday morning with a Gale Warning taking over until Thursday
  morning.

* Southern Inner Waters: Fresh to strong northwest winds of 20 to 25
  kt with gusts of +35kt (mainly in the lee of Cape Mendocino) will
  maintain steep seas. A Gale Warning has taken effect and will
  remain in effect through late this evening.

* Southern Outer Waters: Gale force conditions develop in the lee
  of Cape Mendocino, where northerly winds of 25 to 30 kt with
  gusts up to 40 kt will yield steep, hazardous combined seas of
  11 to 12 ft. A Gale Warning remains in effect through Thursday
  morning.


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 9 AM PDT Thursday for PZZ450.

     Small Craft Advisory until 6 AM PDT early this morning for
     PZZ470.

     Gale Warning from 6 AM this morning to 9 AM PDT Thursday
     for PZZ470.

     Gale Warning until 9 AM PDT Thursday 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