Alert archive / California / Frost Advisories in 2021
Frost Advisory 51, NWS Eureka, CA
NWS Eureka, CA issued this frost advisory at Nov 20, 2021, 2:32 AM PST for 4 counties in California. It took effect at Nov 21, 2021, 1:00 AM PST. It was in force for 9 hr.
The area
The counties it named.
The facts
- Issued
- Nov 20, 2021, 2:32 AM PST (10:32 UTC)
- In effect from
- Nov 21, 2021, 1:00 AM PST
- Expired
- Nov 21, 2021, 10:00 AM PST
- In force
- 9 hr
- Issued by
- NWS Eureka, CA
Counties Del Norte County, CA, Humboldt County, CA, Lake County, CA, Mendocino County, CA
The radar
The Eureka (Bunker Hill) radar (KBHX), 72 km from the middle of the area, began a volume at 10:31 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, 10.5 hours before the alert went out and 244 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.
- Mixed-layer CAPE
- 3 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 791 m above ground
- 0-6 km bulk shear
- 27 kt
- 0-1 km storm-relative helicity
- -8 m²/s²
- 0-3 km storm-relative helicity
- -14 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
938 WWUS76 KEKA 201032 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 232 AM PST Sat Nov 20 2021 CAZ106-110-111-113>115-202215- /O.NEW.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Southern Humboldt Interior-Northwestern Mendocino Interior- Northeastern Mendocino Interior-Southeastern Mendocino Interior- Northern Lake-Southern Lake- 232 AM PST Sat Nov 20 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 10 AM PST SUNDAY ACROSS INTERIOR VALLEYS... * WHAT...Overnight and early morning temperatures will range from 32 to 36 degrees and result in frost formation across interior valleys. * WHERE...Southern Humboldt Interior, Northwestern Mendocino Interior, Northeastern Mendocino Interior, Southeastern Mendocino Interior, Northern Lake and Southern Lake Counties. * WHEN...From 1 AM to 10 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
4 follow-up statements
115 WWUS76 KEKA 201524 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 724 AM PST Sat Nov 20 2021 CAZ102-103-105-109-112-202330- /O.EXA.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Del Norte Interior-Northern Humboldt Coast- Northern Humboldt Interior-Mendocino Coast- Southwestern Mendocino Interior- 724 AM PST Sat Nov 20 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 10 AM PST SUNDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Del Norte Interior, Northern Humboldt Coast, Northern Humboldt Interior, Mendocino Coast and Southwestern Mendocino Interior Counties. * WHEN...From 1 AM to 10 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ106-110-111-113>115-202330- /O.CON.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Southern Humboldt Interior-Northwestern Mendocino Interior- Northeastern Mendocino Interior-Southeastern Mendocino Interior- Northern Lake-Southern Lake- 724 AM PST Sat Nov 20 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 10 AM PST SUNDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Southeastern Mendocino Interior, Northeastern Mendocino Interior, Northern Lake, Southern Humboldt Interior, Southern Lake and Northwestern Mendocino Interior Counties. * WHEN...From 1 AM to 10 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
759 WWUS76 KEKA 202207 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 207 PM PST Sat Nov 20 2021 CAZ103-112-202315- /O.CAN.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Northern Humboldt Coast-Southwestern Mendocino Interior- 207 PM PST Sat Nov 20 2021 ...FROST ADVISORY IS CANCELLED... $$ CAZ102-105-106-109>111-113>115-210615- /O.CON.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Del Norte Interior-Northern Humboldt Interior- Southern Humboldt Interior-Mendocino Coast- Northwestern Mendocino Interior-Northeastern Mendocino Interior- Southeastern Mendocino Interior-Northern Lake-Southern Lake- 207 PM PST Sat Nov 20 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 10 AM PST SUNDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Mendocino Coast, Del Norte Interior, Southeastern Mendocino Interior, Northwestern Mendocino Interior, Northeastern Mendocino Interior, Northern Humboldt Interior, Northern Lake, Southern Humboldt Interior and Southern Lake Counties. * WHEN...From 1 AM to 10 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
703 WWUS76 KEKA 210538 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 938 PM PST Sat Nov 20 2021 CAZ102-105-106-109>111-113>115-211800- /O.CON.KEKA.FR.Y.0051.211121T0900Z-211121T1800Z/ Del Norte Interior-Northern Humboldt Interior- Southern Humboldt Interior-Mendocino Coast- Northwestern Mendocino Interior-Northeastern Mendocino Interior- Southeastern Mendocino Interior-Northern Lake-Southern Lake- 938 PM PST Sat Nov 20 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 10 AM PST SUNDAY... * WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...Mendocino Coast, Del Norte Interior, Southeastern Mendocino Interior, Northwestern Mendocino Interior, Northeastern Mendocino Interior, Northern Humboldt Interior, Northern Lake, Southern Humboldt Interior and Southern Lake Counties. * WHEN...From 1 AM to 10 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
330 WWUS76 KEKA 211745 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 945 AM PST Sun Nov 21 2021 CAZ102-105-106-109>111-113>115-211845- /O.EXP.KEKA.FR.Y.0051.000000T0000Z-211121T1800Z/ Del Norte Interior-Northern Humboldt Interior- Southern Humboldt Interior-Mendocino Coast- Northwestern Mendocino Interior-Northeastern Mendocino Interior- Southeastern Mendocino Interior-Northern Lake-Southern Lake- 945 AM PST Sun Nov 21 2021 ...FROST ADVISORY WILL EXPIRE AT 10 AM PST THIS MORNING... $$
Nearby
Frost Advisories in California, 2021Every frost advisory in 2021
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.