Alert archive / California / Frost Advisories in 2021
Frost Advisory 36, NWS Eureka, CA
NWS Eureka, CA issued this frost advisory at May 19, 2021, 2:35 PM PDT for 5 counties in California. It took effect at May 20, 2021, 1:00 AM PDT. It was in force for 8 hr.
The area
The counties it named.
The facts
- Issued
- May 19, 2021, 2:35 PM PDT (21:35 UTC)
- In effect from
- May 20, 2021, 1:00 AM PDT
- Expired
- May 20, 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 21:35 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, 9.6 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
- 971 m above ground
- 0-6 km bulk shear
- 66 kt
- 0-1 km storm-relative helicity
- -16 m²/s²
- 0-3 km storm-relative helicity
- 84 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
294 WWUS76 KEKA 192135 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 235 PM PDT Wed May 19 2021 CAZ106-108-200545- /O.UPG.KEKA.FZ.A.0005.210520T0800Z-210520T1600Z/ /O.NEW.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ Southern Humboldt Interior-Southern Trinity- 235 PM PDT Wed May 19 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT THURSDAY... * WHAT...Temperatures as low as 30 will result in frost formation. * WHERE...Southern Humboldt Interior and Southern Trinity Counties. * WHEN...From 1 AM to 9 AM PDT 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. && $$ CAZ110-112>115-200545- /O.CON.KEKA.WI.Y.0010.210520T0100Z-210521T0000Z/ Northwestern Mendocino Interior-Southwestern Mendocino Interior- Southeastern Mendocino Interior-Northern Lake-Southern Lake- 235 PM PDT Wed May 19 2021 ...WIND ADVISORY REMAINS IN EFFECT FROM 6 PM THIS EVENING TO 5 PM PDT THURSDAY ABOVE 2000 FEET... * WHAT...Northwest winds 10 to 20 mph with gusts up to 50 mph expected above 2,000 feet. * WHERE...Southwestern Mendocino Interior, Southeastern Mendocino Interior, Northwestern Mendocino Interior, Northern Lake and Southern Lake Counties. * WHEN...From 6 PM this evening to 5 PM PDT Thursday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. && $$
3 follow-up statements
088 WWUS76 KEKA 200109 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 609 PM PDT Wed May 19 2021 CAZ110-113>115-200915- /O.EXA.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ /O.CON.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ Northwestern Mendocino Interior-Southeastern Mendocino Interior- Northern Lake-Southern Lake- 609 PM PDT Wed May 19 2021 ...WIND ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY... ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT THURSDAY... * WHAT...For the Frost Advisory, temperatures as low as 33 will result in frost formation. For the Wind Advisory, northwest winds 20 to 30 mph with gusts up to 45 mph. * WHERE...Northwestern Mendocino Interior, Southeastern Mendocino Interior, Northern Lake and Southern Lake Counties. * WHEN...For the Frost Advisory, from 1 AM to 9 AM PDT Thursday. For the Wind Advisory, until 5 PM PDT Thursday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. 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. && $$ CAZ102-104-105-107-111-200915- /O.EXA.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ Del Norte Interior-Southwestern Humboldt- Northern Humboldt Interior-Northern Trinity- Northeastern Mendocino Interior- 609 PM PDT Wed May 19 2021 ...FROST ADVISORY IN EFFECT FROM 1 AM TO 9 AM PDT THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Del Norte Interior, Southwestern Humboldt, Northern Humboldt Interior, Northern Trinity and Northeastern Mendocino Interior Counties. * WHEN...From 1 AM to 9 AM PDT Thursday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ106-108-200915- /O.CON.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ Southern Humboldt Interior-Southern Trinity- 609 PM PDT Wed May 19 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 1 AM TO 9 AM PDT THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Southern Trinity and Southern Humboldt Interior Counties. * WHEN...From 1 AM to 9 AM PDT 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. && $$ CAZ112-200915- /O.CON.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ Southwestern Mendocino Interior- 609 PM PDT Wed May 19 2021 ...WIND ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY... * WHAT...Northwest winds 15 to 25 mph with gusts up to 45 mph. * WHERE...Southwestern Mendocino Interior County. * WHEN...Until 5 PM PDT Thursday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. && $$
229 WWUS76 KEKA 200545 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 1045 PM PDT Wed May 19 2021 CAZ110-113>115-201345- /O.CON.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ /O.CON.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ Northwestern Mendocino Interior-Southeastern Mendocino Interior- Northern Lake-Southern Lake- 1045 PM PDT Wed May 19 2021 ...WIND ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY... ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THURSDAY... * WHAT...For the Wind Advisory, northwest winds 20 to 30 mph with gusts up to 45 mph. For the Frost Advisory, temperatures as low as 33 will result in frost formation. * WHERE...Southeastern Mendocino Interior, Northwestern Mendocino Interior, Northern Lake and Southern Lake Counties. * WHEN...For the Wind Advisory, until 5 PM PDT Thursday. For the Frost Advisory, until 9 AM PDT Thursday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. 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. && $$ CAZ102-104>108-111-201345- /O.CON.KEKA.FR.Y.0036.210520T0800Z-210520T1600Z/ Del Norte Interior-Southwestern Humboldt- Northern Humboldt Interior-Southern Humboldt Interior- Northern Trinity-Southern Trinity-Northeastern Mendocino Interior- 1045 PM PDT Wed May 19 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THURSDAY... * WHAT...Temperatures as low as 33 will result in frost formation. * WHERE...Southern Trinity, Del Norte Interior, Northeastern Mendocino Interior, Northern Humboldt Interior, Southwestern Humboldt, Northern Trinity and Southern Humboldt Interior Counties. * WHEN...Until 9 AM PDT Thursday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ112-201345- /O.CON.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ Southwestern Mendocino Interior- 1045 PM PDT Wed May 19 2021 ...WIND ADVISORY REMAINS IN EFFECT UNTIL 5 PM PDT THURSDAY... * WHAT...Northwest winds 15 to 25 mph with gusts up to 45 mph. * WHERE...Southwestern Mendocino Interior County. * WHEN...Until 5 PM PDT Thursday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. && $$
165 WWUS76 KEKA 201035 NPWEKA URGENT - WEATHER MESSAGE National Weather Service Eureka CA 335 AM PDT Thu May 20 2021 CAZ113-115-201600- /O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ /O.NEW.KEKA.WI.Y.0011.210520T1900Z-210521T0000Z/ /O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/ Southeastern Mendocino Interior-Southern Lake- 335 AM PDT Thu May 20 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... ...WIND ADVISORY IN EFFECT FROM NOON TODAY TO 5 PM PDT THIS AFTERNOON... * WHAT...For the Frost Advisory, temperatures as low as 35 will result in frost formation. For the Wind Advisory, northwest winds 15 to 25 mph with gusts up to 40 to 45 mph expected. * WHERE...Portions of the Southeastern Mendocino Interior and Southern Lake Counties. * WHEN...For the Frost Advisory, until 9 AM PDT this morning. For the Wind Advisory, from noon today to 5 PM PDT this afternoon. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. Take steps now to protect tender plants from the cold. Frost Advisories and Freeze Warnings are issued during the local growing season as defined by climatology and local agriculture experts. Once the growing season has ended these statements will no longer be issued until the spring. && $$ CAZ110-114-201600- /O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ /O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/ Northwestern Mendocino Interior-Northern Lake- 335 AM PDT Thu May 20 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... ...WIND ADVISORY IS CANCELLED... * WHAT...Temperatures in the low to mid 30s will result in frost formation. * WHERE...Northwestern Mendocino Interior and Northern Lake 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. && $$ CAZ112-201600- /O.CAN.KEKA.WI.Y.0010.000000T0000Z-210521T0000Z/ /O.NEW.KEKA.WI.Y.0011.210520T1900Z-210521T0000Z/ Southwestern Mendocino Interior- 335 AM PDT Thu May 20 2021 ...WIND ADVISORY IN EFFECT FROM NOON TODAY TO 5 PM PDT THIS AFTERNOON... * WHAT...Northwest winds 15 to 25 mph with gusts up to 40 to 45 mph expected. * WHERE...Southwestern Mendocino Interior County. * WHEN...From noon today to 5 PM PDT this afternoon. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result. PRECAUTIONARY/PREPAREDNESS ACTIONS... Use extra caution when driving, especially if operating a high profile vehicle. Secure outdoor objects. && $$ CAZ102-104>108-111-201600- /O.CON.KEKA.FR.Y.0036.000000T0000Z-210520T1600Z/ Del Norte Interior-Southwestern Humboldt- Northern Humboldt Interior-Southern Humboldt Interior- Northern Trinity-Southern Trinity-Northeastern Mendocino Interior- 335 AM PDT Thu May 20 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 portions of Southern Trinity, Del Norte Interior, Northeastern Mendocino Interior, Northern Humboldt Interior, Southwestern Humboldt, 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. && $$
The office that day
Everything else NWS Eureka, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 18, 5:23 PM PDT | Gale Warning | EKA | 27 hr | |
| May 19, 4:00 AM PDT | Freeze Watch | EKA | Humboldt, Trinity | 11 hr |
| May 19, 12:15 PM PDT | Wind Advisory | EKA | Lake, Mendocino | 15 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.