Alert archive / California / Freeze Warnings in 2018

Freeze Warning 5, NWS Eureka, CA

April 16, 2018Mendocino County, California

NWS Eureka, CA issued this freeze warning at Apr 16, 2018, 3:15 AM PDT for Mendocino County, California. It took effect at Apr 16, 2018, 11:00 PM PDT. It was in force for 11 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 16, 2018, 3:15 AM PDT (10:15 UTC)
In effect from
Apr 16, 2018, 11:00 PM PDT
Expired
Apr 17, 2018, 10:00 AM PDT
In force
11 hr
Issued by
NWS Eureka, CA

County Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 139 km from the middle of the area, began a volume at 10:17 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Oakland, CA (KOAK), launched 00:00Z, 10.3 hours before the alert went out and 218 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, Oakland, CA at 00:00Z on 2018-04-16Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Oakland, CA at 00:00Z on 2018-04-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
975 m above ground
0-6 km bulk shear
74 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
141 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

717 
WWUS76 KEKA 161015
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
315 AM PDT Mon Apr 16 2018

CAZ102-161115-
/O.CAN.KEKA.FZ.A.0002.180417T0600Z-180417T1700Z/
Del Norte Interior-
315 AM PDT Mon Apr 16 2018

...FREEZE WATCH IS CANCELLED...

The National Weather Service in Eureka has cancelled the Freeze
Watch. 

Temperatures in most areas are not expected to drop below
freezing.

$$

CAZ107-108-162315-
/O.UPG.KEKA.HZ.A.0003.180417T0600Z-180417T1700Z/
/O.NEW.KEKA.HZ.W.0003.180417T0600Z-180417T1700Z/
Northern Trinity-Southern Trinity-
315 AM PDT Mon Apr 16 2018

...HARD FREEZE WARNING IN EFFECT FROM 11 PM THIS EVENING TO 10 AM
PDT TUESDAY...

The National Weather Service in Eureka has issued a Hard Freeze
Warning...which is in effect from 11 PM this evening to 10 AM PDT
Tuesday. The Hard Freeze Watch is no longer in effect. 

* LOW TEMPERATURES...Mid to upper 20s.

* LOCATIONS INCLUDE...Weaverville...Burnt Ranch...Trinity
  Center...Hayfork...Ruth.

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

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

CAZ110-111-162315-
/O.UPG.KEKA.FZ.A.0002.180417T0600Z-180417T1700Z/
/O.NEW.KEKA.FZ.W.0005.180417T0600Z-180417T1700Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
315 AM PDT Mon Apr 16 2018

...FREEZE WARNING IN EFFECT FROM 11 PM THIS EVENING TO 10 AM PDT
TUESDAY...

The National Weather Service in Eureka has issued a Freeze
Warning...which is in effect from 11 PM this evening to 10 AM PDT
Tuesday. The Freeze Watch is no longer in effect. 

* LOW TEMPERATURES...Around 30.

* LOCATIONS INCLUDE...Leggett...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.

&&

$$

CAZ105-106-113-162315-
/O.UPG.KEKA.FZ.A.0002.180417T0600Z-180417T1700Z/
/O.NEW.KEKA.FR.Y.0010.180417T0600Z-180417T1700Z/
Northern Humboldt Interior-Southern Humboldt Interior-
Southeastern Mendocino Interior-
315 AM PDT Mon Apr 16 2018

...FROST ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 10 AM PDT
TUESDAY...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect from 11 PM this evening to 10 AM
PDT Tuesday. The Freeze Watch is no longer in effect. 

* LOW TEMPERATURES...mid 30s.

* LOCATIONS INCLUDE...Orleans...Willow Creek...Garberville... 
  Bridgeville...Ukiah...Hopland.

* 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.

&&

$$

CAZ104-109-112-162315-
/O.NEW.KEKA.FR.Y.0010.180417T0600Z-180417T1700Z/
Southwestern Humboldt-Mendocino Coast-
Southwestern Mendocino Interior-
315 AM PDT Mon Apr 16 2018

...FROST ADVISORY IN EFFECT FROM 11 PM THIS EVENING TO 10 AM PDT
TUESDAY...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect from 11 PM this evening to 10 AM
PDT Tuesday. 

* LOW TEMPERATURES...mid 30s.

* LOCATIONS INCLUDE...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
907 
WWUS76 KEKA 162041
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
141 PM PDT Mon Apr 16 2018


CAZ107-108-170945-
/O.CON.KEKA.HZ.W.0003.180417T0600Z-180417T1700Z/
Northern Trinity-Southern Trinity-
141 PM PDT Mon Apr 16 2018

...HARD FREEZE WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING
TO 10 AM PDT TUESDAY...

* LOW TEMPERATURES...Mid to upper 20s.

* LOCATIONS INCLUDE...Hayfork...Ruth...Weaverville...Burnt
  Ranch...Trinity Center.

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

$$

CAZ110-111-170945-
/O.CON.KEKA.FZ.W.0005.180417T0600Z-180417T1700Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
141 PM PDT Mon Apr 16 2018

...FREEZE WARNING REMAINS IN EFFECT FROM 11 PM THIS EVENING TO
10 AM PDT TUESDAY...

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

* LOCATIONS INCLUDE...Leggett...Laytonville...Willits...Covelo.

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

$$

CAZ104>106-109-112-113-170945-
/O.CON.KEKA.FR.Y.0010.180417T0600Z-180417T1700Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Mendocino Coast-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
141 PM PDT Mon Apr 16 2018

...FROST ADVISORY REMAINS IN EFFECT FROM 11 PM THIS EVENING TO
10 AM PDT TUESDAY...

* LOW TEMPERATURES...Mid 30s.

* LOCATIONS INCLUDE...Fort Bragg...Point Arena...Boonville...
  Comptche...Ukiah...Hopland...Orleans...Willow Creek...
  Petrolia...Honeydew...Ettersberg...Garberville...Bridgeville.

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

$$
068 
WWUS76 KEKA 171003
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
303 AM PDT Tue Apr 17 2018

CAZ107-108-171700-
/O.CON.KEKA.HZ.W.0003.000000T0000Z-180417T1700Z/
Northern Trinity-Southern Trinity-
303 AM PDT Tue Apr 17 2018

...HARD FREEZE WARNING REMAINS IN EFFECT UNTIL 10 AM PDT THIS
MORNING...

* LOW TEMPERATURES...Mid to upper 20s in the coldest spots.

* LOCATIONS INCLUDE...Hayfork...Ruth...Weaverville...Burnt
  Ranch...Trinity Center.

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

$$

CAZ110-111-171700-
/O.CON.KEKA.FZ.W.0005.000000T0000Z-180417T1700Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
303 AM PDT Tue Apr 17 2018

...FREEZE WARNING REMAINS IN EFFECT UNTIL 10 AM PDT THIS
MORNING...

* LOW TEMPERATURES...Lower 30s.

* LOCATIONS INCLUDE...Leggett...Laytonville...Willits...Covelo....

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

$$

CAZ104>106-109-112-113-171700-
/O.CON.KEKA.FR.Y.0010.000000T0000Z-180417T1700Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Mendocino Coast-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
303 AM PDT Tue Apr 17 2018

...FROST ADVISORY REMAINS IN EFFECT UNTIL 10 AM PDT THIS
MORNING...

* LOW TEMPERATURES...mid 30s.

* LOCATIONS INCLUDE...Fort Bragg...Boonville...
  Comptche...Ukiah...Hopland...Orleans...Willow Creek...
  Petrolia...Honeydew...Ettersberg...Garberville...Bridgeville.

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

$$
784 
WWUS76 KEKA 171638
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
938 AM PDT Tue Apr 17 2018


CAZ107-108-171745-
/O.EXP.KEKA.HZ.W.0003.000000T0000Z-180417T1700Z/
Northern Trinity-Southern Trinity-
938 AM PDT Tue Apr 17 2018

...HARD FREEZE WARNING WILL EXPIRE AT 10 AM PDT THIS MORNING...

$$

CAZ110-111-171745-
/O.EXP.KEKA.FZ.W.0005.000000T0000Z-180417T1700Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
938 AM PDT Tue Apr 17 2018

...FREEZE WARNING WILL EXPIRE AT 10 AM PDT THIS MORNING...

$$

CAZ104>106-109-112-113-171745-
/O.EXP.KEKA.FR.Y.0010.000000T0000Z-180417T1700Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Mendocino Coast-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
938 AM PDT Tue Apr 17 2018

...FROST ADVISORY WILL EXPIRE AT 10 AM PDT THIS MORNING...

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 16, 3:15 AM PDTFrost AdvisoryEKAHumboldt, Mendocino31 hr
Apr 16, 3:15 AM PDTHard Freeze WarningEKATrinity31 hr

Nearby

Freeze Warnings in California, 2018Every freeze warning in 2018

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; radar from the NEXRAD Level II archive.