Alert archive / California / Frost Advisories in 2017

Frost Advisory 21, NWS Eureka, CA

October 5, 2017Mendocino County, Trinity County, California

NWS Eureka, CA issued this frost advisory at Oct 5, 2017, 6:43 PM PDT for Mendocino County, Trinity County, California. It took effect at Oct 6, 2017, 2:00 AM PDT. It was in force for 6 hr.

The area

The counties it named.

The facts

Issued
Oct 5, 2017, 6:43 PM PDT (01:43 UTC)
In effect from
Oct 6, 2017, 2:00 AM PDT
Expired
Oct 6, 2017, 7:37 AM PDT
In force
6 hr
Issued by
NWS Eureka, CA

Counties Mendocino County, CA, Trinity County, CA

The radar

The Eureka (Bunker Hill) radar (KBHX), 100 km from the middle of the area, began a volume at 01:45 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 00:00Z, 1.7 hours before the alert went out and 262 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 00:00Z on 2017-10-06Temperature 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 00:00Z on 2017-10-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 7 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3299 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
7 m²/s²
0-3 km storm-relative helicity
41 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

486 
WWUS76 KEKA 060143
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
643 PM PDT Thu Oct 5 2017


CAZ107-108-110-111-061445-
/O.NEW.KEKA.FR.Y.0021.171006T0900Z-171006T1600Z/
Northern Trinity-Southern Trinity-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-
643 PM PDT Thu Oct 5 2017

...FROST ADVISORY IN EFFECT FROM 2 AM TO 9 AM PDT FRIDAY...

The National Weather Service in Eureka has issued a Frost
Advisory...which is in effect from 2 AM to 9 AM PDT Friday. 

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

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

&&

$$
1 follow-up statement
622 
WWUS76 KEKA 061437
NPWEKA

URGENT - WEATHER MESSAGE
National Weather Service Eureka CA
737 AM PDT Fri Oct 6 2017

CAZ107-108-110-111-061545-
/O.CAN.KEKA.FR.Y.0021.000000T0000Z-171006T1600Z/
Northern Trinity-Southern Trinity-Northwestern Mendocino Interior-
Northeastern Mendocino Interior-
737 AM PDT Fri Oct 6 2017

...FROST ADVISORY IS CANCELLED...

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



$$

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 5, 9:43 PM PDTGale WatchEKA41 hr
Oct 5, 9:43 PM PDTSmall Craft AdvisoryEKA53 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.