Alert archive / California / Frost Advisories in 2021
Frost Advisory 34, NWS Eureka, CA
NWS Eureka, CA issued this frost advisory at May 7, 2021, 2:03 PM PDT for Humboldt County, Mendocino County, Trinity County, California. It took effect at May 8, 2021, 1:00 AM PDT. It was in force for 8 hr.
The area
The counties it named.
The facts
- Issued
- May 7, 2021, 2:03 PM PDT (21:03 UTC)
- In effect from
- May 8, 2021, 1:00 AM PDT
- Expired
- May 8, 2021, 9:00 AM PDT
- In force
- 8 hr
- Issued by
- NWS Eureka, CA
Counties Humboldt County, CA, Mendocino County, CA, Trinity County, CA
The radar
The Eureka (Bunker Hill) radar (KBHX), 73 km from the middle of the area, began a volume at 21:07 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, 9.1 hours before the alert went out and 241 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
- 1114 m above ground
- 0-6 km bulk shear
- 42 kt
- 0-1 km storm-relative helicity
- -9 m²/s²
- 0-3 km storm-relative helicity
- 26 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
151 WWUS76 KEKA 072103 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 203 PM PDT Fri May 7 2021 CAZ103-105>108-111-080515- /O.NEW.KEKA.FR.Y.0034.210508T0800Z-210508T1600Z/ Northern Humboldt Coast-Northern Humboldt Interior- Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northeastern Mendocino Interior- 203 PM PDT Fri May 7 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT SATURDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Northern Humboldt Coast, Northern Humboldt Interior, Southern Humboldt Interior, Northern Trinity, Southern Trinity and Northeastern Mendocino Interior Counties. * WHEN...From 1 AM to 9 AM PDT Saturday. * 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. && $$
2 follow-up statements
639 WWUS76 KEKA 080519 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 1019 PM PDT Fri May 7 2021 CAZ103-105>108-111-081600- /O.CON.KEKA.FR.Y.0034.210508T0800Z-210508T1600Z/ Northern Humboldt Coast-Northern Humboldt Interior- Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northeastern Mendocino Interior- 1019 PM PDT Fri May 7 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT SATURDAY... * WHAT...Temperatures in the low to mid 30s will result in frost formation. * WHERE...Sheltered colder valleys in Southern Trinity, Northern Humboldt Coast, Northeastern Mendocino Interior, Northern Humboldt Interior, Northern Trinity and Southern Humboldt Interior. * WHEN...Until 9 AM PDT Saturday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
437 WWUS76 KEKA 081037 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 337 AM PDT Sat May 8 2021 CAZ103-105>108-111-081600- /O.CON.KEKA.FR.Y.0034.000000T0000Z-210508T1600Z/ Northern Humboldt Coast-Northern Humboldt Interior- Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northeastern Mendocino Interior- 337 AM PDT Sat May 8 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Southern Trinity, Northern Humboldt Coast, Northeastern Mendocino Interior, Northern Humboldt Interior, Northern Trinity and Southern Humboldt Interior Counties. * WHEN...Until 9 AM PDT 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. && $$
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.