329
FXUS66 KEKA 062303
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
403 PM PDT Thu Jun 6 2024

.SYNOPSIS...There remain a very slight chance of isolated
thunderstorms over high terrain of Trinity county this afternoon.
High temperatures will cool a couple degrees on Friday across the
interior. Additional cooling is expected with high temperatures
returning closer to seasonal normals for the weekend. Warmer
temperatures are expected again next week.

&&

.DISCUSSION...An upper level trough is starting to approach the
area. This is expected to start a cooling trend for Friday and
into the weekend. Highs are only expected to cool a couple
degrees Friday with an additional 5 to 8 degrees for the weekend.
This will bring the highs back closer to seasonal normals. This
trough will also bring the threat for thunderstorms over the
higher terrain of eastern Trinity county. This will likely allow
stratus to return near the coast. Some stratus is possible
tonight, but the probabilities from the HREF are only around 20
percent. The better chance for stratus is expected to be Friday
night. This will also bring the potential for some drizzle in the
coastal areas. There is also the potential for thunderstorms each
afternoon Friday and into the weekend. Models are showing some
instability and the CAMS are showing some projected light radar
returns. However at this point the flow aloft is expected to be
southwest and the mid level lapse rates are poor. So given the
unfavorable pattern and low probabilities have left them out of
the forecast for now.

Next week high pressure starts to build into the area again and
temperatures are expected to warm above normal again. The current
models are showing highs only reaching 100 in the hotter valleys.
The NBM is showing a 40 to 50 percent chance of temperatures
exceeding 100 in Ukiah on Tuesday. MKK

&&

.AVIATION...A low cloud layer that was forming near Patricks Point
has finally burned out giving way to VFR conditions over KACV. At
the coastal sites, there is limited visibility forecasted due to
onshore winds as well as large breaking waves, allowing aerosols
over the terminals creating a thinly concentrated haze. Visibilities
are expected to remain above 4SM for the TAF period. Strong north
winds at KCEC could possibly lead to mystery cloud layers later this
afternoon in the METAR readings due to this increased ocean-haze.
Overnight, there is a 40-60% probability of a coastal stratus layer
returning to the coastal sites tonight after midnight. Therefore,
due to low confidence in the current guidance, this  resurgence has
yet to be referenced in the TAF. Inland at KUKI, it is another
relatively quiet day of weather. Diurnal flow is the main driver
of the TAF changes with breezy northwest wind along the Russian
River valley during the afternoons evolving into calm nighttime
conditions. Only a 20% chance of cloud coverage is expected to
form, and if it does it should be in the early hours of the
morning tomorrow. DS

&&

.MARINE...Today we are seeing a combination of multiple different
wave groups leading to a sea state that remains quite chaotic. A
locally generated wave group is forming due gale force northerly
winds accelerating past Cape Blanco and Cape Mendocino. Winds in
these locations are forecasted to reach gale force this afternoon
with probabilities of sustained winds over 35 mph at 100% and
probabilities over 40 mph are at 20% according to model guidance.
These robust winds are forecasted to last until the early hours of
tomorrow morning. These local waves in addition with a NW swell
arriving from a deep low pressure system over the Aleutian Islands
in Alaska. These two interacting wave groups have heights of 11ft
and 6ft (wind and across-swell respectively), yet with varying
periods between 14-8 seconds, causing a hazardous sea state with
significant sea heights of 14-13ft. The Aleutian based swell will
die off into the weekend. Another oceanic storm system being
influenced by the current low in the Aleutians and will bring a long
(15-13 sec) period swell to our waters on Saturday, increasing wave
heights again. DS

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Heat Advisory until 8 PM PDT this evening for CAZ114-115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 9 PM PDT Friday for PZZ450.

     Small Craft Advisory until noon PDT Friday for PZZ455.

     Hazardous Seas Warning until 3 PM PDT this afternoon for
     PZZ470.

     Gale Warning until 3 AM PDT Friday for PZZ470.

     Hazardous Seas Warning until 3 AM PDT Friday for PZZ475.

&&

$$

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