697
FXUS66 KEKA 260911
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
211 AM PDT Thu Jun 26 2025

.SYNOPSIS...Breezier winds possible today through Friday, bringing
elevated fire weather concerns. Seasonable temperatures are expected
to continue today through Friday, followed by hotter weather this
weekend and into early next week. Moderate to locally major HeatRisk
this weekend, especially on Sunday.


&&

.DISCUSSION...Coastal stratus has been slightly deeper along the
north Cape Mendocino compared with yesterday`s reading. The marine
layer depth around 3000 feet MSL per McKinleyville profiler.
Patchy drizzle have been occurring as result of the saturated
layer. Low clouds are expected to erode back to the coast with the
diurnal heating, but will be stubborn to clear out along the
coast. However, coastal stratus will gradually lift and mix out
during the afternoon as another approaching weak shortwave
destabilize the marine layer.

Seasonable temperatures for late June along breezy northwesterly
winds will continue through Friday. Expect gusts around 20-25 mph
through the channeled terrine, while 30-35 mph over the more
exposed ridges.


The offshore ridges will moves over the area this weekend and
into early next week, and a warm deep-layer air-mass will develop
across the WRN- CONUS. Meanwhile, a reversal upper-level trough
forming off the coast of California. Model guidance has been very
consistent supporting 850 mb temperatures of 25-30C or so over the
eastern portion of the forecast area, including interior
Mendocino, Lake and Trinity counties. Interior heat will build on
Friday and then peak on Sunday. High temperatures in the hottest
valleys are expected to range from 97 to 105F degrees. The HeatRisk
is forecast to be Minor to Moderate over the area, but a locally
Major HeatRisk is anticipated to occur over portions of Trinity
County on Sunday. At this point, those major HeatRisk are
expected over isolated areas in the northeastern Trinity valleys.
The heat will have impacts on some individuals sensitive to heat,
especially those without effective cooling and/or adequate
hydration. However, we are going to continue monitoring in case a
heat product is needed. Even the coastal areas are expected to
warm up into the 70`s before the seas breezes developed.


The influence of the upper- level low off the coast along with
the heat could possibly bring the potential for some dry
thunderstorms. Confidence is low as the position of the upper-
level low is uncertain and will determine how much moisture is
available for convection.

Ensembles shows the high pressure shifting eastward on day 5
(Monday) as a week shortwave approaches the area, while the low
spinning off the California Coast moves onshore. Hot weather is
expected to continue on Monday and Tuesday next week. There is
much more confidence for the potential of thunderstorms (20%
chance) on Monday and Tuesday for the Klamath Mountains. /ZVS


&&

.AVIATION...Satellite depicts a deeper marine layer and stratus
blanketed the coastal areas, and extended well up the adjacent
river valleys. The marine layer depth is up to 3000 feet per the
McKinleyville profiler. Variable conditions have been occurring
along the coastal terminals as high level clouds spread across the
area from the northwest. MVFR ceilings, lowering to IFR at around
600-900 feet around 11Z. With a weakened inversion, low clouds are
expected to lift and mix out during the afternoon. This will bring
a period of VFR conditions at ACV and possible a brief improvement
conditions at CEC. VFR conditions will prevail at UKI. Light and
variable winds this morning, becoming breezy NW at 10-15, with
gusts up to around 20 kts...especially at ACV and UKI. During the
evening,the marine layer will redeveloped along the coast with
MVFR ceilings. /ZVS

&&

.MARINE...Fresh to strong northerly breezes will continue across
the southern waters, with isolated gusts over 30 kts downwind Cape
Mendocino. Gentle to moderate northerly winds for the northern
zones, ranging only up to around 15 kts through Thursday. Seas
will be mostly controlled by short period wind waves with only a
minor northwest mid period swell. Northerly winds will increase
again and spread north on Friday and through the weekend. Strong
to Gale Force gusts conditions across the southern waters Friday
afternoon through late Friday night. A thermal trough move close
to the coast on Saturday and the pressure gradient tighten, strong
to near gale sustained winds across the outer waters. There is a
potential (40 to 65 percent) for near gale to gale force gusts on
Saturday across the outer waters. /ZVS

&&

.FIRE WEATHER...Hot and drier weather conditions is forecast for
this weekend and early next week. Low daytime RH`s in the teens
are expected this weekend, primarily in eastern Mendocino, Trinity
and Lake counties. Overnight recoveries will be good to moderate
in the valleys and moderate in the higher terrain. Except for
some enhanced north wind right along shore and channeled along the
Eel river valley on Saturday, daytime winds will be mostly gentle
and terrain driven. If the upper-level low off the coast is
positioned in a way to bring enough moisture into the area,
convection is not out of the question. As of now, thunderstorm
probabilities remain low (less than 10%) for the weekend. However,
confidence continue increasing with the potential of thunderstorms
(20% chance) on Monday and Tuesday for the Klamath Mountains. ZVS


&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 3 AM PDT Saturday for PZZ455.

     Small Craft Advisory until 1 PM PDT Friday for PZZ475.

     Gale Watch from Friday afternoon through late Friday night
     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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https://www.weather.gov/images/eka/zonemap.png