620
FXUS66 KEKA 272206
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
306 PM PDT Mon May 27 2024

.SYNOPSIS...Due to the continuing upper level ridge over the Western
US, high temperatures will be warm and summer-like for inland areas
today. This evening and overnight, a trough will move through the
Pacific Northwest bringing subsequent moisture and cooler
temperatures to Northwest California. By the middle to end of the
week, a ridge will build back in bringing warmer temperatures,
especially for Friday.



&&

.DISCUSSION...Stratus continues to erode away toward the coast, due
to day time heating, bringing mostly clear skies and pleasantly
seasonable temperatures for coastal areas today. With the clear
skies inland and high pressure overhead, interior valleys will have
slightly warmer than average high temperatures in the low to mid
80s. Coastal temperatures will range from the upper 50s to low 60s
with breezy onshore winds building throughout the day.

Another weak shortwave associated with a trough moving into the
Pacific Northwest will traverse the region this evening and into the
early morning allowing for some moisture and instability to migrate
through. This combined with the increased temperatures today will
enhance instability, bringing the potential for some light rain
showers to pop up in the higher terrain areas of Trinity and
Mendocino counties by this evening. The chance for thunder is non-
zero, but with little mid-level moisture and low lapse rates,
chances are low. NBM gives around a 10 percent probability to see
thunder, while SREF gives around a 20 percent chance. Overnight
tonight, the moisture brought in by the weak shortwave will aid in
the development of a deepened marine layer and even some drizzle
along the coast by early tomorrow morning. Also, widespread high
altitude cloud cover tomorrow will lead to cooler temperatures for
inland areas by tomorrow afternoon.

A ridging pattern will develop by mid week and gradually warm the
region through the end of the week, particularly the interior. For
the interior, mid to high 80s are forecast for Thursday, while high
80s to low 90s are forecast for Friday. Also, some coastal regions
could warm to the mid 60s by Friday with the help of offshore flow.
Afternoon wind gusts are possible as well, with probabilities for
wind gusts above 25 mph between 50 and 70 percent along most of the
coast by Thursday. Ensemble members are starting to show some
agreement on a weaker ridge persisting at least through Saturday.
/JLW & /DS


&&

.AVIATION...Skies have mostly cleared early this afternoon,
although some MVFR stratus lingers in the Eel River Delta and south
of Humboldt Bay. Low cloud and drizzle are expected to redevelop
late this evening and overnight along the Redwood and portions of
the Mendo coast...with most guidance trending toward stratus
development, indicating ceilings remaining primarily MVFR. Otherwise
VFR will prevail across the interior.


&&

.MARINE...A weak northerly wind pattern persists. Winds continue to
be accelerated south of Cape Mendocino where localized gusts up to
35 kts and short period seas of 6 to 8 feet create Small Craft
Advisory conditions. The steepened seas in the northern waters will
drop to 5 ft or less today as winds drop to 15 kt or less. Expect
very similar conditions to continue Tuesday. A mid period NW swell
at around 5 ft at 13 seconds from a late season Pacific trough of
low pressure will also arrive on Tuesday. Building high pressure
Wednesday and Thursday will increase northerly winds in all zones.
There is growing probability for gale conditions through that
period.


&&

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

&&

$$

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