Alert archive / California / Frost Advisories in 2017

Frost Advisory 20, NWS Eureka, CA

October 4, 2017Humboldt County, Mendocino County, California

NWS Eureka, CA issued this frost advisory at Oct 4, 2017, 2:46 PM PDT for Humboldt County, Mendocino County, California. It took effect at Oct 5, 2017, 12:00 AM PDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Oct 4, 2017, 2:46 PM PDT (21:46 UTC)
In effect from
Oct 5, 2017, 12:00 AM PDT
Expired
Oct 5, 2017, 9:00 AM PDT
In force
9 hr
Issued by
NWS Eureka, CA

Counties Humboldt County, CA, Mendocino County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 71 km from the middle of the area, began a volume at 21:48 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

Medford/Jackson, OR (KMFR), launched 12:00Z, 9.8 hours before the alert went out and 266 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 2017-10-04Temperature 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, Medford/Jackson, OR at 12:00Z on 2017-10-04The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -17 square meters per square second.193958Sfc1 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
1908 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-17 m²/s²
0-3 km storm-relative helicity
47 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

142 
WWUS76 KEKA 042146
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
246 PM PDT Wed Oct 4 2017

CAZ107-108-110-051100-
/O.NEW.KEKA.FZ.W.0006.171005T0700Z-171005T1600Z/
Northern Trinity-Southern Trinity-Northwestern Mendocino Interior-
246 PM PDT Wed Oct 4 2017

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PDT
THURSDAY...

The National Weather Service in Eureka has issued a Freeze
Warning...which is in effect from midnight tonight to 9 AM PDT
Thursday. 

* LOW TEMPERATURES...upper 20s to low 30s.

* LOCATIONS INCLUDE...Weaverville...Burnt Ranch...Trinity
  Center...Hayfork...Ruth...Leggett...Laytonville...Willits.

* 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.

&&

$$

CAZ104>106-109-111>113-051100-
/O.NEW.KEKA.FR.Y.0020.171005T0700Z-171005T1600Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Mendocino Coast-
Northeastern Mendocino Interior-Southwestern Mendocino Interior-
Southeastern Mendocino Interior-
246 PM PDT Wed Oct 4 2017

...FROST ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PDT
THURSDAY...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect from midnight tonight to 9 AM PDT
Thursday. 

* LOW TEMPERATURES...low to mid 30s.

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

* 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.

&&

$$
4 follow-up statements
577 
WWUS76 KEKA 042157
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
257 PM PDT Wed Oct 4 2017

CAZ111-051100-
/O.UPG.KEKA.FR.Y.0020.171005T0700Z-171005T1600Z/
/O.EXA.KEKA.FZ.W.0006.171005T0700Z-171005T1600Z/
Northeastern Mendocino Interior-
257 PM PDT Wed Oct 4 2017

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PDT
THURSDAY...

The National Weather Service in Eureka has issued a Freeze
Warning...which is in effect from midnight tonight to 9 AM PDT
Thursday. The Frost Advisory is no longer in effect. 

* LOW TEMPERATURES...mid 20s to low 30s.

* LOCATIONS INCLUDE...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.

&&

$$

CAZ107-108-110-051100-
/O.CON.KEKA.FZ.W.0006.171005T0700Z-171005T1600Z/
Northern Trinity-Southern Trinity-Northwestern Mendocino Interior-
257 PM PDT Wed Oct 4 2017

...FREEZE WARNING REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
PDT THURSDAY...

* LOW TEMPERATURES...upper 20s to low 30s.

* LOCATIONS INCLUDE...Weaverville...Burnt Ranch...Trinity
  Center...Hayfork...Ruth...Leggett...Laytonville...Willits.

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

$$

CAZ104>106-109-112-113-051100-
/O.CON.KEKA.FR.Y.0020.171005T0700Z-171005T1600Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Mendocino Coast-
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
257 PM PDT Wed Oct 4 2017

...FROST ADVISORY REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
PDT THURSDAY...

* LOW TEMPERATURES...low to mid 30s.

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

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

$$
144 
WWUS76 KEKA 050344
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
844 PM PDT Wed Oct 4 2017

CAZ109-050445-
/O.CAN.KEKA.FR.Y.0020.171005T0700Z-171005T1600Z/
Mendocino Coast-
844 PM PDT Wed Oct 4 2017

...FROST ADVISORY IS CANCELLED...

The National Weather Service in Eureka has cancelled the Frost
Advisory. 


$$

CAZ107-108-110-111-051600-
/O.CON.KEKA.FZ.W.0006.171005T0700Z-171005T1600Z/
Northern Trinity-Southern Trinity-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-
844 PM PDT Wed Oct 4 2017

...FREEZE WARNING REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
PDT THURSDAY...

* LOW TEMPERATURES...upper 20S to mid 30s.

* LOCATIONS INCLUDE...Hayfork...Ruth...Leggett...Laytonville...
  Willits...Covelo...Weaverville...Burnt ...Ranch...Trinity Center.

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


$$

CAZ104>106-112-113-051600-
/O.CON.KEKA.FR.Y.0020.171005T0700Z-171005T1600Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Southwestern Mendocino Interior-
Southeastern Mendocino Interior-
844 PM PDT Wed Oct 4 2017

...FROST ADVISORY REMAINS IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM
PDT THURSDAY...

* LOW TEMPERATURES...mid 30s.

* LOCATIONS INCLUDE...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



$$
294 
WWUS76 KEKA 051018
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
318 AM PDT Thu Oct 5 2017

CAZ110-111-051600-
/O.CAN.KEKA.FZ.W.0006.000000T0000Z-171005T1600Z/
/O.EXA.KEKA.FR.Y.0020.000000T0000Z-171005T1600Z/
Northwestern Mendocino Interior-Northeastern Mendocino Interior-
318 AM PDT Thu Oct 5 2017

...FROST ADVISORY IN EFFECT UNTIL 9 AM PDT THIS MORNING...
...FREEZE WARNING IS CANCELLED...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect until 9 AM PDT this morning. the
Freeze Warning has been canceled. 

* LOW TEMPERATURES...Low to mid 30s.

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

&&

$$

CAZ112-113-051130-
/O.CAN.KEKA.FR.Y.0020.000000T0000Z-171005T1600Z/
Southwestern Mendocino Interior-Southeastern Mendocino Interior-
318 AM PDT Thu Oct 5 2017

...FROST ADVISORY IS CANCELLED...

The National Weather Service in Eureka has cancelled the Frost
Advisory. 

$$

CAZ107-108-051600-
/O.CON.KEKA.FZ.W.0006.000000T0000Z-171005T1600Z/
Northern Trinity-Southern Trinity-
318 AM PDT Thu Oct 5 2017

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

* LOW TEMPERATURES...Upper 20S to mid 30s.

* LOCATIONS INCLUDE...Hayfork...Ruth for most likely freeze. Most
  other areas slightly warmer but frost still possible. 

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

$$

CAZ104>106-051600-
/O.CON.KEKA.FR.Y.0020.000000T0000Z-171005T1600Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-
318 AM PDT Thu Oct 5 2017

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

* LOCATIONS INCLUDE...Willow
  Creek...Honeydew...Garberville...Redway.

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

$$
079 
WWUS76 KEKA 051554
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
854 AM PDT Thu Oct 5 2017

CAZ107-108-051700-
/O.EXP.KEKA.FZ.W.0006.000000T0000Z-171005T1600Z/
Northern Trinity-Southern Trinity-
854 AM PDT Thu Oct 5 2017

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

This will be the final statement issued for this event.

$$

CAZ104>106-110-111-051700-
/O.EXP.KEKA.FR.Y.0020.000000T0000Z-171005T1600Z/
Southwestern Humboldt-Northern Humboldt Interior-
Southern Humboldt Interior-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-
854 AM PDT Thu Oct 5 2017

...FROST ADVISORY WILL EXPIRE AT 9 AM PDT THIS MORNING...

This will be the final statement issued for this event.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 4, 12:24 AM PDTFrost AdvisoryEKATrinity9 hr
Oct 4, 2:46 PM PDTFreeze WarningEKAMendocino, Trinity18 hr

Nearby

Frost Advisories in California, 2017Every frost advisory 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; radar from the NEXRAD Level II archive.