Alert archive / California / Frost Advisories in 2021
Frost Advisory 35, NWS Eureka, CA
NWS Eureka, CA issued this frost advisory at May 18, 2021, 3:43 AM PDT for 5 counties in California. It took effect at May 19, 2021, 1:00 AM PDT. It was in force for 8 hr.
The area
The counties it named.
The facts
- Issued
- May 18, 2021, 3:43 AM PDT (10:43 UTC)
- In effect from
- May 19, 2021, 1:00 AM PDT
- Expired
- May 19, 2021, 9:00 AM PDT
- In force
- 8 hr
- Issued by
- NWS Eureka, CA
Counties Del Norte County, CA, Humboldt County, CA, Lake County, CA, Mendocino County, CA, Trinity County, CA
The radar
The Eureka (Bunker Hill) radar (KBHX), 75 km from the middle of the area, began a volume at 10:41 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, 10.7 hours before the alert went out and 233 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
- 3103 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 20 m²/s²
- 0-3 km storm-relative helicity
- 176 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
839 WWUS76 KEKA 181043 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 343 AM PDT Tue May 18 2021 CAZ106>108-111-181845- /O.NEW.KEKA.FR.Y.0035.210519T0800Z-210519T1600Z/ Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northeastern Mendocino Interior- 343 AM PDT Tue May 18 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT WEDNESDAY... * WHAT...Temperatures in the low to mid 30s will result in frost formation. * WHERE...Sheltered valleys in the Southern Humboldt Interior, Northern Trinity, Southern Trinity and Northeastern Mendocino County. * WHEN...From 1 AM to 9 AM PDT Wednesday. * 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. && $$
3 follow-up statements
956 WWUS76 KEKA 181843 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 1143 AM PDT Tue May 18 2021 CAZ102-105-110-114-190445- /O.EXA.KEKA.FR.Y.0035.210519T0800Z-210519T1600Z/ Del Norte Interior-Northern Humboldt Interior- Northwestern Mendocino Interior-Northern Lake- 1143 AM PDT Tue May 18 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM WEDNESDAY... * WHAT...Temperatures as low as 34 will result in frost formation. * WHERE...Del Norte Interior, Northern Humboldt Interior, Northwestern Mendocino Interior and Northern Lake Counties. * WHEN...From 1 AM to 9 AM Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. $$ CAZ106>108-111-190445- /O.CON.KEKA.FR.Y.0035.210519T0800Z-210519T1600Z/ Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northeastern Mendocino Interior- 1143 AM PDT Tue May 18 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM WEDNESDAY... * WHAT...Temperatures as low as 32 will result in frost formation. A few normally colder spots may dip to just below freezing for an hour or two prior to sunrise. * WHERE...Trinity, Northeastern Mendocino Interior, and Southern Humboldt Interior Counties. * WHEN...From 1 AM to 9 AM Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. $$
655 WWUS76 KEKA 190322 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 822 PM PDT Tue May 18 2021 CAZ102-105>108-110-111-114-191130- /O.CON.KEKA.FR.Y.0035.210519T0800Z-210519T1600Z/ Del Norte Interior-Northern Humboldt Interior- Southern Humboldt Interior-Northern Trinity-Southern Trinity- Northwestern Mendocino Interior-Northeastern Mendocino Interior- Northern Lake- 822 PM PDT Tue May 18 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM PDT WEDNESDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Southern Trinity, Northeastern Mendocino Interior, Northwestern Mendocino Interior, Del Norte Interior, Northern Humboldt Interior, Northern Trinity, Southern Humboldt Interior and Northern Lake Counties. * WHEN...From 1 AM to 9 AM PDT Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$
803 WWUS76 KEKA 191100 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 400 AM PDT Wed May 19 2021 CAZ111-114-191200- /O.CAN.KEKA.FR.Y.0035.000000T0000Z-210519T1600Z/ Northeastern Mendocino Interior-Northern Lake- 400 AM PDT Wed May 19 2021 ...FROST ADVISORY IS CANCELLED... $$ CAZ106-108-191600- /O.NEW.KEKA.FZ.A.0005.210520T0800Z-210520T1600Z/ /O.CON.KEKA.FR.Y.0035.000000T0000Z-210519T1600Z/ Southern Humboldt Interior-Southern Trinity- 400 AM PDT Wed May 19 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... ...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH THURSDAY MORNING... * WHAT...For the Frost Advisory, temperatures in the low to mid 30s will result in frost formation. For the Freeze Watch, sub- freezing temperatures in the low 30s and upper 20s possible. * WHERE...Southern Humboldt Interior and Southern Trinity Counties. * WHEN...For the Frost Advisory, until 9 AM PDT this morning. For the Freeze Watch, from late tonight through Thursday morning. * IMPACTS...Frost and freeze conditions could kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Provide adequate shelter for outdoor pets or consider bringing them indoors. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ102-105-107-110-191600- /O.CON.KEKA.FR.Y.0035.000000T0000Z-210519T1600Z/ Del Norte Interior-Northern Humboldt Interior-Northern Trinity- Northwestern Mendocino Interior- 400 AM PDT Wed May 19 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... * WHAT...Temperatures in the low to mid 30s will result in frost formation. * WHERE...Sheltered valleys in the Northwestern Mendocino Interior, Del Norte Interior, Northern Humboldt Interior and Northern Trinity 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. && $$
The office that day
Everything else NWS Eureka, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 17, 8:28 PM PDT | Gale Watch | EKA | 21 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.