497
FXUS66 KEKA 020707
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1207 AM PDT Sat Aug 2 2025

.SYNOPSIS...Interior thunderstorms around the Trinity Horn will
be possible over the weekend, primarily on Sunday. Ridging into
this coming week will warm temperatures with potential for another
trough next week.


&&

.DISCUSSION...A recurring theme of late afternoon convective
weather will continue to a lesser degree this weekend. The usual
areas around the Klamath Mountains could have showers or
thunderstorms this weekend with extreme NE regions of Trinity
County the most likely location for any shower/thunderstorm
development. The potential for thunderstorms decrease
substantially on Saturday with drier westerly flow spreading
across the area and higher 500mb heights. A colder trough will
approach on Sunday bringing yet another round of showers and
thunderstorms to the interior mountains. Otherwise, this trough
will bring cooler temps and gusty westerly and northwesterly winds
Sun and into Mon.

Interior temperatures will likely begin to warm by Tuesday or
Wednesday of next week. The duration of warmer temperatures
remains uncertain. 500mb heights pump up to 588DM or more by late
next week and suspect some of the typically hot valley locations
will reach or exceed 100F. Even coastal areas have a potential for
high temperatures reaching the mid to upper 60s by later in the week.
The risk for a long duration heat wave may be mitigated by
persistent and frequent troughs busting down on the ridge from the
NW. Deterministic models are starting to indicate a flow pattern
favorable for more interior convection and thunderstorms late next
week/early next weekend with a closed 500mb circulation offshore
the California coast and ESE winds aloft.


&&

.AVIATION...The upper level trough west of the area continues to
bring stratus to much of the coast. This is expected to gradually
drop down to LIFR in most areas this morning. A shortwave moving
through the flow may bring some increased drizzle this morning which
may actually ceilings slightly. This afternoon there will likely be
some lifting of the clouds, but these may just lift to IFR in the
afternoon. Inland areas may see a few thunderstorms again in the
afternoon, but these are expected to limited to northern Trinity
county. Monday evening the coastal stratus is expected to expand
again. MKK


&&

.MARINE...An upper level trough just off the coast is keeping the
winds around 15 to 25 kt with the stronger winds south of Cape
Mendocino. The waves are mainly short period and driven by the local
winds. These are stronger south of Cape Mendocino where they peak
around 7 feet. Winds are expected to increase slightly on Sunday as
the upper level trough moves by the area early on Sunday. The small
craft advisories may need to be expanded and/or extended, but it
looks borderline at this point so will hold off for another shift or
two. Monday the winds are expected to start to diminish, but are
expected to remain in the 10 to 20 kt range through early Thursday.
Friday it looks like stronger northerly winds will return.

The waves are expected to continue to be mainly in response to the
local winds. The 1 to 2 foot southerly swell is currently moving
through the waters and there will likely continue to be some small
southerly swells at times over the next week.

The Tsunami continues to produce small waves. These are mainly less
than 6 inches in Crescent City now. They are expected to continue to
diminish, but may continue to bring some increased currents and
surges for a bit longer. MKK


&&

.FIRE WEATHER...We will continue to include a headline in the
fire weather forecast for isolated thunderstorms and possible new
ignitions. Temperatures aloft and stability will likely increase
on Saturday and result in a significant reduction in
thunderstorms probabilities for our forecast area. A short
wavelength trough will approach on Sunday and then progress across
the area Sunday night. Granted the trough may slow down and
arrive as late as Monday. This trough will bring another round of
showers and thunderstorms for the Klamath Mountains, mostly around
the Trinity Horn. This trough on Sunday will likely induce
stronger westerly to northwest winds for our typically dry and
windy areas; Lake, southern Mendocino and eastern Trinity.



&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 3 PM PDT Sunday for PZZ455-475.

&&

$$

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