Weitchpec, California Weather Forecast Discussion

514
FXUS66 KEKA 252145
AFDEKA
AREA FORECAST DISCUSSION
National Weather Service Eureka CA
245 PM PDT Thu Sep 25 2025
.SYNOPSIS...Warm and dry weather will persist this week. Dry
northerly flow will clear out most of the coastal stratus this
week, allowing for better duration of coastal sunshine. Rain
chances arrive late Sunday, with increasing probability for
widespread rainfall through early next week. The opportunity for
additional rainfall may continue through mid next week.
&&
.DISCUSSION...High pressure is building into the Pacific Northwest
and the upper level low is moving off to the east. This is
expected to set up offshore flow and increase temperatures. The
offshore flow is expected to clear skies out this afternoon along
the coast and these will likely remain clear overnight. Some
patchy fog is possible around Humboldt Bay. The gusts over the
ridges tonight may be around 10 to 20 mph. Friday afternoon
breezes are expected again with gusts to 25 mph, strongest over
the ridges, along the coast and in Lake county. Saturday looks dry
and sunny as well with a few coastal clouds possible around
sunrise. Winds are generally expected to be light.
Sunday is expected to be mainly dry as a fairly strong frontal
boundary approaches the area. This is expected to bring gusty
winds ahead of the front, especially in the afternoon. This may
increase fire danger, but RH is expected to be increasing at the
same time and this may limit the fire potential. Southerly winds
are expected to be the strongest along the Humboldt and Del Norte
coasts and higher terrain. Currently it looks like gusts of 30 to
40 mph are possible in the strongest areas. Rain is expected to
start at some point Sunday evening or overnight in the north with
rain reaching Lake county by Monday morning. By 5pm Monday the NBM
is showing 0.5 to 0.75 inches in Mendocino and Lake counties with
0.75 to 1.25 inches farther north. The ensembles continue to show
over a 50 percent probability of IVT values remaining between 250
and 500 kg/m/s. This highlights the potential for heavier rain
rates and totals may be higher than expected.
Tuesday another round of moderate to heavy rain is expected,
however due to the longer lead time there is a much bigger range
of potential solutions. Still it looks like it will be another
warm and wet system with some periods of moderate to heavy rain.
&&
.AVIATION...LIFR conditions are likely to improve at the coastal
terminals despite prolonged low instrument flight rules lasting
through 19z. Wind bearings are also likely to change from their
southerly and westerly prevailing directions as the pressure
gradient gets stronger along the coast. Hires models show scattering
and clearing as stout northerlies scour out cloud groups with the
zonal flow and ridging on the backside of the open wave upper low,
making its way eastward towards the four corners. Satellite products
in the visible spectrum show eroding stratus being thinned out at
KCEC as of 20z. Expect VFR for a few hours this afternoon with
periods of IFR/MVFR tonight as the previously mentioned gusty
northerlies set in.  KACV will take a bit longer to improve as LIFR
is likely to prevail into the early evening but will eventually lift
ceilings and scatter out by 22z-23z. Frontal boundaries approach with
moisture bands in tow and will bring rain Sunday evening as the next
upper low pressure system rolls down from the Alaskan and Canadian
coast. KUKI will have prevailing VFR conditions with northerly winds
picking up in the early evening. /EYS
&&
.MARINE...Northerly winds are increasing as the pressure
gradient gets steeper and strengthens. Gale Warnings have been
hoisted for the northern and southern outer waters in regards to the
expected hazard as observations and buoys are reporting increased
winds already this afternoon. Gusts up to 45 knots will also make
for hazardous sea conditions as wind waves combined with swell will
make a choppy and confused sea state lasting tonight through
Saturday afternoon. Expect steep waves peaking at 12-14 feet over
the next 48 hours with a northwest swell around 6 - 8 feet at
15 -16 seconds maxing out Friday evening. /EYS
&&
.FIRE WEATHER...This afternoon breezy northerly winds are in place
along with RH mainly in the 20 to 30 percent range in the
interior areas. Tonight there is expected to be generally good
recoveries in the valleys with moderate recoveries of only 40 to
50 percent over the higher terrain. Breezy offshore flow will
bring some stronger winds over the higher terrain as well. Friday
afternoon RH is expected to drop into the teens in many areas
across the interior with very few coastal clouds returning.
Friday afternoon northerly winds will surge south through the
Sacramento Valley and over the higher terrain of eastern Lake
County in the afternoon. This direction is favorable to be terrain
enhanced, and will create some locally critical fire weather
conditions given the dry minimum RH values. The critical
conditions will be localized and mainly over the higher terrain.
Friday night poor RH recoveries are expected over the higher
terrain with moderate recoveries in the valleys. Winds will mainly
be light and terrain driven limiting the impact of the dry air.
Saturday night into Sunday RH is expected to increase ahead of a
strong cold front. At the same time southerly winds are expected
to increase. The tricky part will be which one increases first.
There could be some periods and locations of increased fire danger
if the winds come up before the RH does. Confidence is fairly
high that most areas will see a wetting rain starting Sunday late
evening in the north and spreading south into Lake county before
midday Monday. Rainfall amounts are expected to range from a half
inch to 1.25 inches with the heaviest amounts in the north and in
the higher terrain. Additional moderate to heavy rain is expected
on Tuesday before drier conditions return Wednesday. MKK
&&
.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
None.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 3 PM PDT Friday for PZZ450.
Small Craft Advisory until 11 PM PDT Friday for PZZ455.
Small Craft Advisory until 11 AM PDT this morning for
     PZZ470.
Gale Warning until 3 AM PDT Saturday for PZZ470.
Small Craft Advisory until 3 PM PDT this afternoon for
     PZZ475.
Gale Warning from 3 PM this afternoon to 3 AM PDT Saturday
     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.
Visit us at https://www.weather.gov/eureka
Follow us on Facebook and Twitter at:
https://www.facebook.com/NWSEureka
https://www.twitter.com/NWSEureka
For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png

NWS EKA Office Area Forecast Discussion