Alert archive / California / Frost Advisories in 2021
Frost Advisory 57, NWS Eureka, CA
NWS Eureka, CA issued this frost advisory at Dec 4, 2021, 2:08 PM PST for Humboldt County, Mendocino County, California. It took effect at Dec 5, 2021, 1:00 AM PST. It was in force for 8 hr.
The area
The counties it named.
The facts
- Issued
- Dec 4, 2021, 2:08 PM PST (22:08 UTC)
- In effect from
- Dec 5, 2021, 1:00 AM PST
- Expired
- Dec 5, 2021, 9:00 AM PST
- In force
- 8 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 22:14 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, 10.1 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 677 m above ground
- 0-6 km bulk shear
- 44 kt
- 0-1 km storm-relative helicity
- 82 m²/s²
- 0-3 km storm-relative helicity
- 149 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
572 WWUS76 KEKA 042208 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 208 PM PST Sat Dec 4 2021 CAZ105-106-109-113-115-050615- /O.NEW.KEKA.FR.Y.0057.211205T0900Z-211205T1700Z/ Northern Humboldt Interior-Southern Humboldt Interior- Mendocino Coast-Southeastern Mendocino Interior-Southern Lake- 208 PM PST Sat Dec 4 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PST SUNDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Northern Humboldt Interior, Southern Humboldt Interior, Mendocino Coast, Southeastern Mendocino Interior and Southern Lake Counties. * WHEN...From 1 AM to 9 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. && $$
2 follow-up statements
348 WWUS76 KEKA 050541 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 941 PM PST Sat Dec 4 2021 CAZ105-106-109-113-115-051700- /O.CON.KEKA.FR.Y.0057.211205T0900Z-211205T1700Z/ Northern Humboldt Interior-Southern Humboldt Interior- Mendocino Coast-Southeastern Mendocino Interior-Southern Lake- 941 PM PST Sat Dec 4 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM PST SUNDAY... * WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...Mendocino Coast, Southeastern Mendocino Interior, Southern Humboldt Interior, Northern Humboldt Interior and Southern Lake Counties. * WHEN...From 1 AM to 9 AM PST Sunday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
136 WWUS76 KEKA 051645 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 845 AM PST Sun Dec 5 2021 CAZ105-106-109-113-115-051745- /O.EXP.KEKA.FR.Y.0057.000000T0000Z-211205T1700Z/ Northern Humboldt Interior-Southern Humboldt Interior- Mendocino Coast-Southeastern Mendocino Interior-Southern Lake- 845 AM PST Sun Dec 5 2021 ...FROST ADVISORY WILL EXPIRE AT 9 AM PST THIS MORNING... $$
The office that day
Everything else NWS Eureka, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 3, 8:53 PM PST | Small Craft Advisory | EKA | 6 hr | |
| Dec 4, 2:53 AM PST | Small Craft Advisory | EKA | 60 hr | |
| Dec 4, 2:11 PM PST | Coastal Flood Advisory | EKA | Humboldt | 23 hr |
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.