Alert archive / California / Hard Freeze Warnings in 2021
Hard Freeze Warning 1, NWS Eureka, CA
NWS Eureka, CA issued this hard freeze warning at Mar 10, 2021, 2:31 PM PST for Lake County, Mendocino County, California. It took effect at Mar 11, 2021, 12:00 AM PST. It was in force for 9 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
- Mar 10, 2021, 2:31 PM PST (22:31 UTC)
- In effect from
- Mar 11, 2021, 12:00 AM PST
- Expired
- Mar 11, 2021, 9:00 AM PST
- In force
- 9 hr
- Issued by
- NWS Eureka, CA
Counties Lake County, CA, Mendocino County, CA
The radar
The Beale AFB radar (KBBX), 128 km from the middle of the area, began a volume at 22:34 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 12:00Z, 10.5 hours before the alert went out and 188 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
- 58 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 700 m above ground
- 0-6 km bulk shear
- 29 kt
- 0-1 km storm-relative helicity
- 102 m²/s²
- 0-3 km storm-relative helicity
- 150 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
916 WWUS76 KEKA 102231 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 231 PM PST Wed Mar 10 2021 CAZ110-111-114-110645- /O.UPG.KEKA.HZ.A.0001.210311T0800Z-210311T1700Z/ /O.NEW.KEKA.HZ.W.0001.210311T0800Z-210311T1700Z/ Northwestern Mendocino Interior-Northeastern Mendocino Interior- Northern Lake County- 231 PM PST Wed Mar 10 2021 ...HARD FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PST THURSDAY... * WHAT...Sub-freezing temperatures as low as 23 expected. * WHERE...Portions of Northwestern Mendocino Interior, Northeastern Mendocino Interior and Northern Lake County Counties. Coldest temperatures in the low to mid 20s will be found in northeast Mendocino County around Covelo. * WHEN...From midnight tonight to 9 AM PST Thursday. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing. 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. && $$ CAZ115-110645- /O.UPG.KEKA.FZ.A.0001.210311T0800Z-210311T1700Z/ /O.NEW.KEKA.FZ.W.0006.210311T0800Z-210311T1700Z/ Southern Lake County- 231 PM PST Wed Mar 10 2021 ...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PST THURSDAY... * WHAT...Sub-freezing temperatures as low as 29 expected. * WHERE...Portions of Southern Lake County, including Upper Lake, Lakeport, and Clearlake. * WHEN...From midnight tonight to 9 AM PST Thursday. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing.. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ109-112-113-110645- /O.UPG.KEKA.FZ.A.0001.210311T0800Z-210311T1700Z/ /O.NEW.KEKA.FR.Y.0007.210311T0800Z-210311T1700Z/ Mendocino Coast-Southwestern Mendocino Interior- Southeastern Mendocino Interior- 231 PM PST Wed Mar 10 2021 ...FROST ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PST THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Portions of the Mendocino Coast just inland, Southwestern Mendocino Interior and Southeastern Mendocino Interior Counties, including Ukiah, Boonville, Hopland, Yorkville, and Navarro. * WHEN...From midnight tonight to 9 AM PST Thursday. * 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. && $$ CAZ103-110645- /O.NEW.KEKA.FR.Y.0007.210311T0800Z-210311T1700Z/ Northern Humboldt Coast- 231 PM PST Wed Mar 10 2021 ...FROST ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM PST THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Portions of the Northern Humboldt Coast, including Blue Lake, McKinleyville, and Arcata. * WHEN...From midnight tonight to 9 AM PST Thursday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
3 follow-up statements
713 WWUS76 KEKA 110646 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 1046 PM PST Wed Mar 10 2021 CAZ110-111-114-111500- /O.CON.KEKA.HZ.W.0001.210311T0800Z-210311T1700Z/ Northwestern Mendocino Interior-Northeastern Mendocino Interior- Northern Lake County- 1046 PM PST Wed Mar 10 2021 ...HARD FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM PST THURSDAY... * WHAT...Sub-freezing temperatures as low as 23 expected. * WHERE...Portions of Northwestern Mendocino Interior, Northeastern Mendocino Interior and Northern Lake County Counties. Coldest temperatures in the low to mid 20s will be found in northeast Mendocino County around Covelo. * WHEN...From midnight tonight to 9 AM PST Thursday. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing. 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. && $$ CAZ115-111500- /O.CON.KEKA.FZ.W.0006.210311T0800Z-210311T1700Z/ Southern Lake County- 1046 PM PST Wed Mar 10 2021 ...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM PST THURSDAY... * WHAT...Sub-freezing temperatures as low as 29 expected. * WHERE...Portions of Southern Lake County, including Upper Lake, Lakeport, and Clearlake. * WHEN...From midnight tonight to 9 AM PST Thursday. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing.. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ103-109-112-113-111500- /O.CON.KEKA.FR.Y.0007.210311T0800Z-210311T1700Z/ Northern Humboldt Coast-Mendocino Coast- Southwestern Mendocino Interior-Southeastern Mendocino Interior- 1046 PM PST Wed Mar 10 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PST THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Portions of the Mendocino Coast just inland, Southwestern Mendocino Interior and Southeastern Mendocino Interior Counties, including Ukiah, Boonville, Hopland, Yorkville, and Navarro. * WHEN...From midnight tonight to 9 AM PST Thursday. * 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. && $$
755 WWUS76 KEKA 111129 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 329 AM PST Thu Mar 11 2021 CAZ110-111-114-111700- /O.CON.KEKA.HZ.W.0001.000000T0000Z-210311T1700Z/ Northwestern Mendocino Interior-Northeastern Mendocino Interior- Northern Lake County- 329 AM PST Thu Mar 11 2021 ...HARD FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM PST THIS MORNING... * WHAT...Sub-freezing temperatures as low as 26. * WHERE...Northeastern Mendocino Interior, Northern Lake County and Northwestern Mendocino Interior. * WHEN...Until 9 AM PST this morning. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ115-111700- /O.CON.KEKA.FZ.W.0006.000000T0000Z-210311T1700Z/ Southern Lake County- 329 AM PST Thu Mar 11 2021 ...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM PST THIS MORNING... * WHAT...Sub-freezing temperatures as low as 29. * WHERE...Southern Lake County County. * WHEN...Until 9 AM PST this morning. * IMPACTS...Frost and freeze conditions will kill crops, other sensitive vegetation and possibly damage unprotected outdoor plumbing. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. To prevent freezing and possible bursting of outdoor water pipes they should be wrapped, drained, or allowed to drip slowly. Those that have in-ground sprinkler systems should drain them and cover above- ground pipes to protect them from freezing.. 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. && $$ CAZ103-109-112-113-111700- /O.CON.KEKA.FR.Y.0007.000000T0000Z-210311T1700Z/ Northern Humboldt Coast-Mendocino Coast- Southwestern Mendocino Interior-Southeastern Mendocino Interior- 329 AM PST Thu Mar 11 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PST THIS MORNING... * WHAT...Temperatures as low as 31 will result in frost formation. * WHERE...Mendocino Coast, Southwestern Mendocino Interior, Southeastern Mendocino Interior and Northern Humboldt Coast. * WHEN...Until 9 AM PST this morning. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
911 WWUS76 KEKA 111645 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 845 AM PST Thu Mar 11 2021 CAZ110-111-114-111745- /O.EXP.KEKA.HZ.W.0001.000000T0000Z-210311T1700Z/ Northwestern Mendocino Interior-Northeastern Mendocino Interior- Northern Lake County- 845 AM PST Thu Mar 11 2021 ...HARD FREEZE WARNING WILL EXPIRE AT 9 AM PST THIS MORNING... $$ CAZ115-111745- /O.EXP.KEKA.FZ.W.0006.000000T0000Z-210311T1700Z/ Southern Lake County- 845 AM PST Thu Mar 11 2021 ...FREEZE WARNING WILL EXPIRE AT 9 AM PST THIS MORNING... $$ CAZ103-109-112-113-111745- /O.EXP.KEKA.FR.Y.0007.000000T0000Z-210311T1700Z/ Northern Humboldt Coast-Mendocino Coast- Southwestern Mendocino Interior-Southeastern Mendocino Interior- 845 AM PST Thu Mar 11 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 |
|---|---|---|---|---|
| Mar 9, 5:52 PM PST | Special Marine Warning | EKA | 23 min | |
| Mar 10, 10:10 AM PST | Winter Weather Advisory | EKA | Lake, Mendocino, Trinity | 6 hr |
| Mar 10, 2:31 PM PST | Frost Advisory | EKA | Humboldt, Mendocino | 18 hr |
| Mar 10, 2:31 PM PST | Freeze Warning | EKA | 18 hr |
Nearby
Hard Freeze Warnings in California, 2021Every hard freeze warning 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.