Alert archive / California / Freeze Warnings in 2017

Freeze Warning 4, NWS Eureka, CA

April 8, 2017Del Norte County, Humboldt County, Mendocino County, California

NWS Eureka, CA issued this freeze warning at Apr 8, 2017, 2:50 PM PDT for Del Norte County, Humboldt County, Mendocino County, California. It took effect at Apr 9, 2017, 1:00 AM PDT. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 8, 2017, 2:50 PM PDT (21:50 UTC)
In effect from
Apr 9, 2017, 1:00 AM PDT
Expired
Apr 9, 2017, 9:00 AM PDT
In force
8 hr
Issued by
NWS Eureka, CA

Counties Del Norte County, CA, Humboldt County, CA, Mendocino County, CA

The nearest sounding before it

Medford/Jackson, OR (KMFR), launched 12:00Z, 9.8 hours before the alert went out and 210 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Medford/Jackson, OR at 12:00Z on 2017-04-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 27 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Medford/Jackson, OR at 12:00Z on 2017-04-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -15 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
27 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
731 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
-15 m²/s²
0-3 km storm-relative helicity
12 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

336 
WWUS76 KEKA 082150
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
250 PM PDT Sat Apr 8 2017

CAZ102-105-106-110-111-113-091600-
/O.NEW.KEKA.FZ.W.0004.170409T0800Z-170409T1600Z/
Del Norte Interior-Northern Humboldt Interior-
Southern Humboldt Interior-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-Southeastern Mendocino Interior-
250 PM PDT Sat Apr 8 2017

...FREEZE WARNING IN EFFECT FROM 1 AM TO 9 AM SUNDAY...

The National Weather Service in Eureka has issued a Freeze
Warning...which is in effect from 1 AM to 9 AM Sunday. 

* LOW TEMPERATURES...Upper 20S to lower 30S.

* LOCATIONS INCLUDE...Willow Creek, Orleans, Laytonville, Willits,
  Covelo.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Freeze Warning means sub-freezing temperatures are imminent or
highly likely. These conditions will kill crops and other
sensitive vegetation.

$$

CAZ103-104-109-112-091600-
/O.NEW.KEKA.FR.Y.0007.170409T0800Z-170409T1600Z/
Northern Humboldt Coast-Southwestern Humboldt-Mendocino Coast-
Southwestern Mendocino Interior-
250 PM PDT Sat Apr 8 2017

...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM SUNDAY...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect from 1 AM to 9 AM Sunday. 

* LOCATIONS INCLUDE...Arcata, Fortuna, Petrolia, Honeydew,
  Ettersberg, Fort Bragg, Boonville, Comptche.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Frost Advisory means that frost is possible. Sensitive outdoor
plants may be killed if left uncovered.

$$
3 follow-up statements
317 
WWUS76 KEKA 082353 AAA
NPWEKA

URGENT - WEATHER MESSAGE...UPDATED
National Weather Service Eureka CA
453 PM PDT Sat Apr 8 2017


CAZ102-105-106-110-111-113-091300-
/O.CON.KEKA.FZ.W.0004.170409T0800Z-170409T1600Z/
Del Norte Interior-Northern Humboldt Interior-
Southern Humboldt Interior-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-Southeastern Mendocino Interior-
453 PM PDT Sat Apr 8 2017

...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 9 AM PDT
SUNDAY...

* LOW TEMPERATURES...Upper 20S to lower 30S.

* LOCATIONS INCLUDE...Willow Creek, Orleans, Laytonville, Willits,
  Covelo.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

$$

CAZ103-104-109-112-091300-
/O.CON.KEKA.FR.Y.0007.170409T0800Z-170409T1600Z/
Northern Humboldt Coast-Southwestern Humboldt-Mendocino Coast-
Southwestern Mendocino Interior-
453 PM PDT Sat Apr 8 2017

...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM PDT
SUNDAY...

* LOCATIONS INCLUDE...Boonville...Comptche...Fortuna
...Patrolia...Honeydew...Ettersberg.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

$$
557 
WWUS76 KEKA 090947
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
247 AM PDT Sun Apr 9 2017


CAZ102-105-106-110-111-113-091600-
/O.CON.KEKA.FZ.W.0004.000000T0000Z-170409T1600Z/
Del Norte Interior-Northern Humboldt Interior-
Southern Humboldt Interior-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-Southeastern Mendocino Interior-
247 AM PDT Sun Apr 9 2017

...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING...

* LOW TEMPERATURES...Upper 20S to lower 30S.

* LOCATIONS INCLUDE...Gasquet...Ukiah...Hopland...Covelo... .. 
....Willow Creek...Orleans...Garberville...Bridgeville... 
Leggett... Laytonville...Willits.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

$$

CAZ103-104-109-112-091600-
/O.CON.KEKA.FR.Y.0007.000000T0000Z-170409T1600Z/
Northern Humboldt Coast-Southwestern Humboldt-Mendocino Coast-
Southwestern Mendocino Interior-
247 AM PDT Sun Apr 9 2017

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING...

* LOCATIONS INCLUDE...Fort Bragg...Point Arena...Boonville...
  Comptche...Arcata...Eureka...Fortuna...Patrolia...Honeydew...
  Ettersberg.

* FOR A DETAILED VIEW OF THE HAZARD AREA...visit 
  http://www.wrh.noaa.gov/map

$$
506 
WWUS76 KEKA 091600
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
900 AM PDT Sun Apr 9 2017

CAZ102-105-106-110-111-113-091700-
/O.EXP.KEKA.FZ.W.0004.000000T0000Z-170409T1600Z/
Del Norte Interior-Northern Humboldt Interior-
Southern Humboldt Interior-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-Southeastern Mendocino Interior-
900 AM PDT Sun Apr 9 2017

...FREEZE WARNING HAS EXPIRED...

$$

CAZ103-104-109-112-091700-
/O.EXP.KEKA.FR.Y.0007.000000T0000Z-170409T1600Z/
Northern Humboldt Coast-Southwestern Humboldt-Mendocino Coast-
Southwestern Mendocino Interior-
900 AM PDT Sun Apr 9 2017

...FROST ADVISORY HAS EXPIRED...

$$

The office that day

Everything else NWS Eureka, CA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 7, 6:35 PM PDTSmall Craft AdvisoryEKA20 hr
Apr 8, 8:52 AM PDTSpecial Weather StatementEKAMendocino53 min
Apr 8, 2:50 PM PDTFrost AdvisoryEKAHumboldt, Mendocino18 hr
Apr 8, 3:12 PM PDTGale WarningEKA30 hr
Apr 8, 3:12 PM PDTSmall Craft AdvisoryEKA66 hr
Apr 8, 3:12 PM PDTSmall Craft AdvisoryEKA64 hr

Nearby

Freeze Warnings in California, 2017Every freeze warning in 2017

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.