Humboldt Hill, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

002
FXUS66 KEKA 032107
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
143 PM PDT Tue Jun 3 2025

.SYNOPSIS...Gusty northerly winds will continue to diminish each
day through the week, but remain robust with steep elevated seas
over the coastal waters. Hot and dry weather will continue each
day this week as a ridge remains parked offshore Northwest
California. Hotter weather is expected this weekend.

&&

.DISCUSSION...

KEY MESSAGES:

- Strong gusty northerly winds at the coast forecast to diminish
  after Wednesday and then continue to ease over the weekend.

- Above normal temperatures expected to continue in the interior
  through the week.

- Moderate HeatRisk increasing this weekend with hotter afternoon
  temperatures in the interior.

- 10% chance for thunderstorms Klamath Mountains and Yolla Bolly
  Wilderness area Sunday through Tuesday.


&&

.DISCUSSION...A strong pressure gradient continues to gradually
diminish along the North Coast. High pressure out in the eastern
Pacific continues to push against a low pressure system ejecting
further south of Northwest California. Northerly winds over the
region will continue to diminish along the North Coast through mid
week. The highest gusts will linger over higher elevations and
particularly at the King Range and the Klamath Mountains of Del
Norte County.

Warm and dry conditions will endure over Northwest California
throughout the week as the ridge persists over the eastern
Pacific. Slightly warmer than average high temperatures can be
expected through the week, especially for the interior. More
average to slightly above average high temperatures are forecast
for the coast this week, with the possibility of marine stratus
over typical coastal areas each night. There is a potential for a
moderate HeatRisk over various interior areas, but especially for
Trinity and Lake counties. Sunday June 8th is expected to be the
warmest day of this next moderate heat wave. Long range ensembles
show generally high confidence in warm, dry conditions continuing
through early June.

Moderate HeatRisk is forecast to expand in coverage over the
weekend as the southern edge of a massive 500mb height anomaly
builds over Oregon and Washington. The robust NE flow is forecast
to abate over the weekend and marine air and stratus will most
likely mitigate the HeatRisk for western portions of Mendocino,
Humboldt and Del Norte Counties.

Another potential high impact going into the weekend into early next
week will be a low chance (10%) for diurnally triggered and terrain
forced thunderstorms (lightning activity) over the Klamath Mountains
and Yolla Bolly`s. A semi-closed low aloft (500mb) is forecast to
bring an increase in mid level humidity and E-SE mid level flow
Sat-Sun. As one might expect for this time of year, deterministic
model soundings (GFS in particular) show inverted-V profiles on
Sunday. We shall see how the models trend over the next day or
two. Flow pattern is chaotic and convectively noisy with low
predictability. NBM thunderstorm probabilities do increase over the
weekend into early next week and for now will message these low
probabilities in the fire weather planning forecast as well.

&&

.AVIATION...

18Z TAF: VFR conditions prevail with NW wind gusts 25 to 35 knots
at CEC early this afternoon. Once again, a significant nearshore
stratus deck has gradually been migrating north from Point Arena
under the influence of a southerly wind reversal. Northward progression
stops south of Cape Mendocino due to strong northerly winds over
the waters. Strong winds will continue at the coastal terminals
and nearby elevated terrain through the afternoon, with gusts
approaching 40 knots while ACV is slightly lighter than previous
days at 15 to 25 knots. As winds ease at the surface this evening,
LLWS is possible at the coast again as NE winds remain elevated
aloft; 30 to 35 knots. Winds will gradually ease at the surface
overnight into early Wednesday morning with potential for haze
development around Humboldt Bay. HREF shows the stratus deck
retreating to Point Arena overnight with around a 50% chance for
ceilings <500 feet along far southern Mendocino coast.

&&

.MARINE...

-Exceptionally strong north winds continue to verify and forecast to
continue this evening with gusts exceeding 40 knots.

-Extremely steep and hazardous seas over 11 to 16 feet are verified
on the buoys and will gradually begin to ease Wednesday, remaining
highest in the southern waters and near Cape Mendocino.

-Mariners should remain in port and alter plans until calmer
conditions develop. Very strong winds and very large waves could
capsize vessels.

A very tight pressure gradient remains between a strong high and an
interior low is causing these abnormally strong northerly winds.
Though the gradient will ease some as the low drifts south, strong
northerlies will continue through much of this week.

Full gales with storm force gusts are forecast to continue tonight
and Wednesday, especially in the outer waters. Gale Warnings remain
in effect for z470 and z475 through Thursday morning, becoming
isolated to z470 through early Friday morning. Gales are probable
for much of this week with highest chances in the outer northern
waters and downwind of Pt St George and local areas downwind of Cape
Mendocino.

Steep northerly waves are expected to propagate into the northern
inner and southern waters through Wednesday, prompting the
continuation of a Hazardous Seas Warning in z450 and a Small Craft
Advisory in z455.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Hazardous Seas Warning until 5 AM PDT Wednesday for PZZ450.

     Small Craft Advisory from 3 AM Wednesday to 3 AM PDT
     Thursday for PZZ455.

     Gale Warning until 3 AM PDT Thursday for PZZ470-475.

&&

$$

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