214
FXUS66 KEKA 152143
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
243 PM PDT Tue Sep 15 2026

.KEY MESSAGES...
* A weak frontal system arriving Wednesday will likely lead to
  cooler temperatures and a few showers or thunderstorms.

* There is a slight chance for thunderstorms in mainly in Trinity,
  Humboldt and Del Norte counties on Wednesday.

* Warmer temperatures and dry conditions return end of the week.

&&

.SYNOPSIS...An upper level low will bring cooler temperatures and
a chance for showers and thunderstorms Wednesday and possibly
Thursday. Warmer and drier conditions are expected Friday and into
the weekend.

&&

.DISCUSSION...An upper level low dropping south over the area is
expected to impact the area Wednesday and Thursday. This is
expected to bring some showers and possible thunderstorms to the
area Wednesday afternoon and evening. The models have come into
better agreement on the location of this low and the instability.
The Hires models are showing a number of showers moving through
the area WEdnesday afternoon. These may continue overnight,
although confidence is low on whether there will be enough
instability for thunderstorms overnight. The GFS does keep 100 to
150 j/kg of MU CAPE over northern Humboldt and Del Norte counties
through much of Thursday night. These storms are not expected to
be particularly dry, but there certainly may be strikes that
occur on the edge of the rainfall cores.

Thursday evening the low is expected to move out of the area,
although this may be slower than currently expected. Still any
showers or thunderstorms should end by sundown on Thursday.

Friday and into the weekend high pressure is expected to build
into the area bringing a return of warm and dry conditions. Winds
are expected to remain fairly light and the marine layer is likely
to be fairly persistent. MKK

&&

.AVIATION...Stratus developed along the coast this morning and has
mostly cleared out this afternoon. Tonight this stratus is
expected to return MVFR to IFR conditions, quickly at ACV and
more slowly in KCEC. Wednesday skies are expected to clear out
again along the as the an upper level low moves overhead and
weakens the inversion. This may also bring a few thunderstorms to
interior Humboldt and Del Norte counties as well as Trinity
county. MKK

&&

.MARINE...The northerly winds persist across the outer waters and
near the capes. A local area of southerly winds has developed just
close to the coast near Crescent City. It is uncertain on when
this will expand, but it is likely to expand by Wednesday
afternoon. The northerlies are also expected to diminish through
the afternoon on Wednesday as southerly winds spread across the
area. These light southerly winds are expected to persist on
Thursday. Locally stronger winds are expected near Crescent City,
especially in the evening. Friday the winds are expected to become
northerly again and increase over the weekend. MKK

&&

.FIRE WEATHER...High pressure building off the coast will
continue the warming and drying trend across Northwest California
today. Wednesday afternoon or overnight an upper low entering over
Del Norte, Humboldt, and N. Trinity counties has the potential to
cause a few thunderstorms. There is still a lot of uncertainty on
the details of these storms, yet the most likely scenario seems
to be storms forming over the Salmon, Klamath, and Trinity Alps
before flowing towards the coast. Confidence is slowly increasing
that there may be some storms with the models becoming
increasingly confident if the track up the upper level low. There
will likely be rain with each of these storms, yet some lightning
that strokes away from the core of the storm could start a fire.
It is possible that the there could be a few storms on Thursday,
but these are expected to be limited to northern Trinity county
and Siskiyou county. Warmer and drier weather along is expected to
return Friday and Saturday. MKK/DS

&&

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

     Small Craft Advisory until 8 PM PDT Wednesday for PZZ455-
     470.

     Small Craft Advisory until 3 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.

Visit us at https://www.weather.gov/eureka

Follow us on Facebook and Twitter at:
https://www.facebook.com/NWSEureka
https://www.twitter.com/NWSEureka

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