Frost Advisory 13, NWS Eureka, CA

705 
WWUS76 KEKA 161538
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
Issued by National Weather Service Medford OR
838 AM PDT Thu Apr 16 2026

CAZ102-105>108-110-111-114-115-162345-
/O.EXP.KEKA.FZ.W.0001.000000T0000Z-260416T1600Z/
/O.CON.KEKA.FZ.W.0002.260417T0700Z-260417T1600Z/
Del Norte Interior-Northern Humboldt Interior-Southern Humboldt
Interior-Northern Trinity-Southern Trinity-Northwestern Mendocino
Interior-Northeastern Mendocino Interior-Northern Lake-Southern
Lake-
Including Forest Glen, Gravelly Valley Airport, Hyampom, Finley,
Orleans, Pepperwood, Willits, Legget, Willow Creek, Weaverville,
Hayfork, Zenia, Junction City, Weitchpec, Douglas City, Trinity
Center, Covelo, Gasquet, Del Loma, Laytonville, Alderpoint, Big
Bar, Peanut, Shively, Dinsmore, Helena, Benbow, Carrville, Potter
Valley, and Bridgeville
838 AM PDT Thu Apr 16 2026

...FREEZE WARNING REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM 
PDT FRIDAY...
...FREEZE WARNING WILL EXPIRE AT 9 AM PDT THIS MORNING...

* WHAT...Sub-freezing temperatures as low as 26 expected.

* WHERE...Trinity County, Lake County, Humboldt Interior, Northern 
  Mendocino Interior, and Del Norte Interior.

* WHEN...From midnight tonight to 9 AM PDT Friday.

* IMPACTS...Frost and freeze conditions could kill crops, other 
  sensitive vegetation and possibly damage unprotected outdoor 
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

CAZ113-161645-
/O.EXP.KEKA.FZ.W.0001.000000T0000Z-260416T1600Z/
Southeastern Mendocino Interior-
838 AM PDT Thu Apr 16 2026

...FREEZE WARNING WILL EXPIRE AT 9 AM PDT THIS MORNING...

$$

CAZ101-103-104-109-112-162345-
/O.EXP.KEKA.FR.Y.0012.000000T0000Z-260416T1600Z/
/O.CON.KEKA.FR.Y.0013.260417T0700Z-260417T1600Z/
Coastal Del Norte-Northern Humboldt Coast-Southwestern Humboldt-
Mendocino Coast-Southwestern Mendocino Interior-
Including Honeydew, Ettersburg, Samoa, McKinleyville, Briceland,
Philo, Arcata, Smith River, Comptche, Whitethorn, Eureka,
Fernbridge, Boonville, Yorkville, Fieldbrook, Ft Dick, Klamath,
and Trinidad
838 AM PDT Thu Apr 16 2026

...FROST ADVISORY REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM 
PDT FRIDAY...
...FROST ADVISORY WILL EXPIRE AT 9 AM PDT THIS MORNING...

* WHAT...Temperatures 33 will result in frost formation.

* WHERE...Del Norte, Humboldt, and Mendocino Coast, and Southwestern 
  Mendocino Interior.

* WHEN...From midnight tonight to 9 AM PDT Friday.

* IMPACTS...Frost could harm sensitive outdoor vegetation. Sensitive 
  outdoor plants may be killed if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

For hazard areas see https://www.wrh.noaa.gov/map/?wfo=eka

535 
WWUS76 KEKA 161941
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
1241 PM PDT Thu Apr 16 2026

CAZ102-105>108-110-111-114-115-162045-
/O.CAN.KEKA.FZ.W.0002.260417T0700Z-260417T1600Z/
Interior Del Norte-Northeastern Interior Humboldt-Southeastern
Interior Humboldt--Southern Trinity-Northwestern Interior
Mendocino-Northeastern Interior Mendocino-Northern Lake--
Including Douglas City, Covelo, Weitchpec, Orleans, Forest Glen,
Hayfork, Big Bar, Peanut, Gravelly Valley Airport, Pepperwood,
Shively, Carrville, Dinsmore, Weaverville, Trinity Center, Gasquet,
and Willow Creek
1241 PM PDT Thu Apr 16 2026 /741 PM UTC Thu Apr 16 2026/

...FREEZE WARNING IS CANCELLED...

Due to changing to the new zones these need to be cancelled and will
be reissued in the next 30 minutes.

$$

CAZ101-103-104-109-112-162045-
/O.CAN.KEKA.FR.Y.0013.260417T0700Z-260417T1600Z/
Coastal Del Norte-Northern Coastal Humboldt-Southwestern Humboldt-
Coastal Mendocino-Southwestern Interior Mendocino-
Including Eureka, Samoa, Trinidad, Boonville, Philo, Honeydew,
Fieldbrook, Briceland, Fernbridge, Ettersburg, Whitethorn,
McKinleyville, and Ft Dick
1241 PM PDT Thu Apr 16 2026

...FROST ADVISORY IS CANCELLED...

Due to changing to the new zones these need to be cancelled and will
be reissued in the next 30 minutes.

$$

For hazard areas see https://www.wrh.noaa.gov/map/?wfo=eka

MKK

AREA FORECAST DISCUSSION
National Weather Service Eureka CA
130 AM PDT Thu Apr 16 2026

.SYNOPSIS...Near freezing to freezing low temperatures expected
to return late week. Breezy winds forecasted for Lake County
through the end of the week. More rain expected late weekend into
next week.

&&

.DISCUSSION...Generally, rain has ended for NW CA. This frontal
system will now force northerly winds throughout the region as the
front moves southeasterly and cold air fills into the area. In
general, coastal areas and higher terrain locations will be gustier.
Through Thursday morning and especially in the afternoon, strong
northerlies will develop in Lake County for the higher terrain areas
in the eastern and southern portions of the county.

Due to this frontal passage, much colder and drier air will advect
over the region. In response, snow levels drop down to ~1,500ft for
Trinity Co. and ~2,000ft for Humboldt Co. This drop did not create
much snow for areas outside of the mountains in northern Trinity Co.
However, this colder air will increase the likelihood for
frost/freeze conditions for the entire area overnight through the
week. Observations show temperatures plummeting due to lack of
insulating cloud coverage for the interior areas. NBM data shows the
interior valleys are forecasted to get colder than 30F Thursday and
Friday mornings. As growing season begins, it is recommended to
cover sensitive plants and take other precautions to protect
agricultural property these mornings. Thursday morning, Freeze
Warnings have been issued for some of the coldest interior valleys,
along with Frost Advisories for most coastal areas.

The GFS and ECMWF are both signaling for another frontal storm
arriving this weekend. The GFS ensemble shows light rain Sunday with
heavier rain possible on Monday. The EPS shows almost the same, with
rain beginning on Saturday evening. What these models also show is
more widespread rainfall over the area with precipitation
accumulations up to 0.75" at lake level in Lake county and
in the valleys of southern Mendocino counties. JLW&DS

&&

.AVIATION...Robust N-NE winds 1000 to 2000 feet AGL will develop
tonight into early Thursday morning in the wake of a cold front.
Low level wind shear and shallow turbulence are expected, especially
around KUKI by 08Z. Gusty northerly winds are forecast to quickly
mix down during the morning hours on Thursday at coastal aerodromes.
Peak wind gusts around 30 kt are forecast by afternoon at both KACV
and KCEC. Turbulent and rough conditions are probable for small and
light weight aircraft. Otherwise, strong subsidence in the wake of a
cold front has been resulting in clearing skies Wednesday night. VFR
is expected to continue to prevail through the day on Thursday at
all forecast terminals.

&&

.MARINE...Vigorous cold front has been producing gusty northerly
winds Wednesday evening. Wind gusts were close to gale at buoy #14
NW of Pt Arena with gusts to 33 kt. Elsewhere, northerlies have been
sub-gale, gusting to 22-30 kt. Seas have also built to hazardous
levels for small vessels, 8 to 9 ft at 8 to 9 seconds. Therefore,
the advisories for small craft are on the mark for the remainder of
tonight. High resolution mesoscale models, GFS and NBM all indicate
northerly winds increasing to gales for mostly the southern waters
on Thu. GFS and NBM also indicate gale gusts developing in the
afternoon for the northern waters. Thus, a gale warning has been
hoisted for the northern outer waters for gusts to 35 kt and steep
waves around 11 feet at 8-10 seconds. Steep waves will also continue
to build through the day on Thursday and peak Thursday night. Max
significant wave heights are projected to hit 13 feet in the
southern waters and 11 feet in the northern waters. On Friday,
elevated seas will steadily subside through the day as winds
diminish below gale. By Saturday, a lighter wind regime is forecast
as an offshore frontal system breaks down the offshore ridge.
Moderate southerly breezes are forecast to develop in advance of the
front Sat night into Sunday. Borderline advisory level winds will be
possible (40% chance) with gusts over 22 kt on Sunday.

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...
     Frost Advisory until 9 AM PDT this morning for CAZ101-103-
     104-109-112.

     Freeze Warning until 9 AM PDT this morning for CAZ102-
     105>108-110-111-113>115.

NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 5 AM PDT Friday for PZZ450.

     Small Craft Advisory until 1 PM PDT this afternoon for
     PZZ455.

     Gale Warning from 1 PM this afternoon to 5 AM PDT Friday
     for PZZ455.

     Small Craft Advisory until 4 PM PDT this afternoon for
     PZZ470.

     Gale Warning from 4 PM this afternoon to 5 AM PDT Friday
     for PZZ470.

     Small Craft Advisory until 5 AM PDT early this morning for
     PZZ475.

     Gale Warning from 5 AM early this morning to 5 AM PDT
     Friday 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