998
FXUS66 KEKA 310713
AFDEKA

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
1213 AM PDT Fri Jul 31 2026

.KEY MESSAGES...
* Hot temperatures return early next week with widespread Moderate
  to locally Major HeatRisk through mid week

* Elevated fire danger returns Saturday and into next week with
  periods of breezy winds and increasingly hot, dry conditions.

* Westerly to northeasterly winds through the weekend and into
  Monday will bring the greatest fire weather risk.

&&

.SYNOPSIS...Temperatures will be trending higher over the next week
with moderate to major HeatRisk possible early next week. Hot
interior temperatures in combination with periods of breezy winds
this weekend through Monday with increase the fire weather risk.


&&

.DISCUSSION...Thursday small upper level low moved past the area
in the afternoon, just bringing a few high clouds. High pressure
buildings in slightly is trying to build back to the west, warming
temperatures well inland by a few degrees. Closer to the coast the
general west to northwest flow at the surface is expected to keep
the coastal counties closer to normal. Stratus is expected to
linger near or just off the this afternoon and quickly push inland
Friday night. Saturday an upper level trough and associated
frontal boundary is moving into the Pacific Northwest. Down here
this front is expected to be dry, but could bring some drizzle
where the marine layer persists. Saturday afternoon this expected
to bring increasing north winds with gusts of 20 to 25 mph along
the coast. Saturday night into Sunday northeast winds are
expected to pick up over the ridges overnight, especially in Del
Norte and Humboldt counties. Sunday afternoon these are expected
to become northwest again and continue to increase.

Sunday night another trough is expected to move through Pacific
Northwest and behind this high pressure starts to build over the
eastern Pacific well off the coast. This brings some of the
strongest winds northeast winds Monday morning in Del Norte and
Humboldt counties. The 850 MB winds on the NAM increase to around
20 to 25 kt with low RH over the higher terrain. This will likely
keep the coastal areas clear with this offshore flow. Hot inland
temperatures are expected with highs over 100 in many of the
valleys across the area. This brings fairly widespread areas of
moderate heat risk. Warmer is expected to continue on Tuesday and
this looks like the hottest day. Highs temperatures of 100 to 107
are expected in the valleys. Winds are expected to be lighter at
the coast Tuesday and this could allow warmer temperatures to get
closer to the coast. The alternate scenario of course is that the
marine layer returns sooner than expected keeping temperatures
cooler. Wednesday inland areas will start to cool by a few degrees
as the ridge starts to get flattened. MKK

&&

.AVIATION...Light winds and mainly VFR conditions continue across
the area this morning. Stratus has developed on the Del Norte and
Humboldt coasts this morning bringing MVFR to IFR CIGS. This
afternoon skies are expected to clear out at the coast again with
some typical afternoon breezes. Confidence is low the on this
clearing as usual. Stratus is expected to return at the coast
again Friday night. MKK

&&

.MARINE...Northerly winds persist across the waters this morning,
these are strongest south of Cape Mendocino with winds of 20 to
25 kt. These have diminished closer to shore this morning, but are
expected to come closer to the coast in the afternoon.

Winds are expected to increase through the day on Saturday with
gale force gusts expected in the afternoon south of Cape
Mendocino. The 20 to 25 kt winds also expand farther north
Saturday night and Sunday. By Sunday afternoon confidence is
fairly high that the outer waters will at least see some gusts to
gale force. It is possible they will come closer to the shore
during the afternoon and evening hours, but will need to wait for
the higher resolution models to get a better idea on that. Monday
afternoon fairly strong gales are expected across the waters and
these are expected to start to diminish on Tuesday. Winds are
expected to be around 10 to 20 kt for much of the rest of the work
week.

In addition to the steep wind driven waves there is a southerly
swell Currently the Cape Mendocino buoy is showing it around 2
feet at 15 seconds. This may build to around 3 feet at and then
slowly diminish through the middle of next week. MKK


&&
.FIRE WEATHER...Lighter winds and gradually increasing overnight
relative humidity recoveries are expected through Saturday morning
as a trough approaches the Pacific Northwest. Stronger marine
layer pushes into the near-coast valleys and along coastal ridges
are likely Friday and Saturday mornings. Farther inland dry air
will remain in place with afternoon relative humidity values
falling into the teens on Friday.

As the trough moves through the region on Saturday the pressure
gradient will tighten resulting in stronger afternoon westerly
winds with chances for gusts over 25 mph increasing to 50 to 70%
for a good portion of the interior Saturday afternoon. Thankfully
the west- northwesterly winds will also bring slightly increased
relative humidity with minimums in the 20s instead of teens. This
will keep the fire threat from becoming critical.

Sunday night into Monday morning is starting to look like a more
critical time period, especially on the ridges of Del Norte
county. Gusts of 30 to 40 mph are are possible on the ridges and
possible the northeast aligned drainages. The is also expected to
be fairly dry. The challenge at this point is determining where
the inversion will be with dry and breezy conditions above and
much calmer and with higher RH below it. This will need to be
monitored as it gets closer. This will also impact the interior
ridges of Humboldt, and Trinity counties.

RH will trend much lower across the interior to the low teens and
likely some single digits by Monday and then remaining dry into mid
next week. Afternoon west-northwesterly gusty winds can be expected
each afternoon. These winds are not expected to be more than typical
for the summer only lasting a few hours and not as strong as
Saturday. MKK/RPA

&&

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

     Gale Watch from Saturday afternoon through late Sunday
     night for PZZ455.

     Small Craft Advisory from 3 PM Saturday to 3 PM PDT Sunday
     for PZZ470.

     Gale Watch from Saturday afternoon through Monday morning
     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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For forecast zone information
see the forecast zone map online:
https://www.weather.gov/images/eka/zonemap.png