Area Forecast Discussion
Issued by NWS Eureka, CA

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FXUS66 KEKA 232201

National Weather Service Eureka CA
301 PM PDT Mon May 23 2022

.SYNOPSIS...Dry conditions and above normal temperatures are
expected through Wednesday. Some of the warmer interior valleys
will approach 100 degrees in eastern Trinity, southern Mendocino
and Lake counties on Wednesday. Cooler temperatures return
Thursday into the weekend, along with a chance of light rain.


.DISCUSSION...Warm temperatures are expected the next several days
with many interior valleys warming into the 90s as upper level
ridging builds over the West Coast. A few isolated areas could
approach 100 degrees on Wednesday, possibly in far southern
Mendocino, Lake, and eastern Trinity counties. This will place
many areas near record high temperatures for this time of year
across the interior. At this time the Heat Risk values do not
indicate a need for heat advisories due to the short nature of
this event and limited areas of 100 degree temps. Coastal areas
will be cooler but still warming above normal into the mid to
upper 60s and lower 70s.

In addition to the warm temperatures, a tight pressure gradient
over California as low pressure gradually moves east through the
Great Basin will bring north-northeasterly winds to portions of
the area, strongest over the ridges of Lake County tonight. Some
gusts over 30 mph are expected bringing a elevated fire weather
concern. See the fire weather discussion below for more info.

By Thursday the ridge will begin to break down as an upper trough
moves toward the Pacific Northwest. General model consensus is
that temperatures will cool over the next few days Thursday into
Saturday with interior areas falling back into the the lower 70s
for highs while coastal areas fall back to the upper 50s and lower
60s. Additionally, this trough will bring a chance of rain to
areas primarily north of Cape Mendocino as multiple storm systems
move into the Pacific Northwest and clip northern California.
Precipitation totals aren`t expected to be all that significant
but there is at least a chance for some wetting rains north of the
Cape into the weekend. /RPA


.AVIATION...Coastal marine stratus extended along the Eel
Delta/nearby river valleys resulting in IFR/LIFR Cigs through
morning. By midday, stratus had started eroding and receding
offshore, although pockets still lingered along the immediate
coast into afternoon. Expect stratus to reform in the
evening...especially around Humboldt Bay to ACV. Elsewhere, Flying
conditions remained VFR. Coastal winds increased in the afternoon
mostly due to funneling flow between pressure systems, but will
decrease overnight as the pressure gradient relaxes. Strong
northerly "above ground" winds expected in the afternoon over
southwestern Humboldt and Coastal Mendocino for possible weak LLWS
at airfields/airport. /TA


.MARINE...A high pressure system in the NE Pacific presses closer to
the coast of Northwest California throughout today and into
Wednesday. As a result, strong breezes to near gale sustained winds
are possible throughout all coastal waters into Tuesday afternoon.
Gale force gusts will occur in the southern outer waters this
afternoon through Tuesday night, particularly in the lee of Cape
Mendocino. Gale force gusts are also expected in the southern inner
waters through late tonight and the northern outer waters late
tonight through very early tomorrow morning. GFS and the ECMWF
indicate a low pressure system moving ashore near Vancouver Island
Tuesday and into Wednesday which will disrupt the strong northerly
winds in our northern waters, making them weaker advisory level
winds for Tuesday afternoon. However, winds over the southern waters
are expected to be at near gale sustained to gale force gusts due to
a pressure and temperature gradient. The temperature gradient is set
up from warmer temperatures in the interior versus the milder
temperatures at the coast. The stronger winds will generate steep
and hazardous seas in the areas affected. A more southerly tracking
low pressure system is expected to disrupt the high pressure system
off our coast into Thursday morning. Gentle to fresh northerly
breezes are expected for the latter half of the week and into the
weekend. There is a possibility of another high pressure system
setting up in the NE Pacific early next week bringing the
possibility of more gusty winds. A series of weak westerly to north
westerly swells are expected throughout the week.


.FIRE WEATHER...Hot and dry conditions will prevail over interior
areas as high pressure builds and slowly shifts eastward. Breezy
north to northeast winds will persist into the middle of the week as
the pressure gradient between the aforementioned high pressure and
trough over the Great Basin persists. Winds will turn more offshore
across the southern portion of the forecast area tonight and into
Tuesday, with some gusty ridgetop winds possible in Lake and
Mendocino counties. The breezy offshore winds will help to bring
even more dry air to the area, particularly in eastern Lake County.
Minimum humidities may dip into the single digits Tuesday afternoon
in some spots, and perhaps again on Wednesday afternoon.

With fuel moistures beginning to fall once again the threat of fire
is increasing but once again, the fuels aren`t to critical levels at
this time. So, for now, maintaining just a headline in the fire
weather forecast and no need for watches or warnings. However,
unless more rain is seen in Lake County and southern Mendocino
County, it might not be long until fuels are to critical levels.
Conditions will rapidly change Thursday with temperatures cooling
sharply as a trough moves into the area. Light rain may return to
the northern portion of the area late in the week. /RPA&JAW


     Small Craft Advisory until 3 PM PDT Tuesday for PZZ450.

     Small Craft Advisory until 9 PM PDT this evening for PZZ470.

     Gale Warning from 9 PM this evening to 3 AM PDT Tuesday for

     Small Craft Advisory until 3 PM PDT this afternoon for

     Gale Warning until 9 PM PDT this evening for PZZ455.

     Gale Warning until 9 PM PDT Tuesday for PZZ475.



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