Alert archive / California / Frost Advisories in 2021
Frost Advisory 4, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this frost advisory at Oct 12, 2021, 2:41 AM PDT for Monterey County, California. It took effect at Oct 13, 2021, 2:00 AM PDT. It was in force for 7 hr.
The area
The counties it named.
The facts
- Issued
- Oct 12, 2021, 2:41 AM PDT (09:41 UTC)
- In effect from
- Oct 13, 2021, 2:00 AM PDT
- Expired
- Oct 13, 2021, 9:00 AM PDT
- In force
- 7 hr
- Issued by
- NWS San Francisco Bay Area, CA
County Monterey County, CA
The radar
The San Francisco radar (KMUX), 115 km from the middle of the area, began a volume at 09:40 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 00:00Z, 9.7 hours before the alert went out and 184 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
- 2078 m above ground
- 0-6 km bulk shear
- 101 kt
- 0-1 km storm-relative helicity
- -174 m²/s²
- 0-3 km storm-relative helicity
- -90 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted.
849 WWUS76 KMTR 120941 NPWMTR URGENT - WEATHER MESSAGE National Weather Service San Francisco Bay Area 241 AM PDT Tue Oct 12 2021 CAZ516-121600- /O.NEW.KMTR.FR.Y.0004.211013T0900Z-211013T1600Z/ /O.CON.KMTR.FR.Y.0003.000000T0000Z-211012T1600Z/ Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Including the cities of Greenfield and King City 241 AM PDT Tue Oct 12 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... ...FROST ADVISORY IN EFFECT FROM 2 AM TO 9 AM PDT WEDNESDAY... * WHAT...For the first Frost Advisory, temperatures as low as 33 will result in frost formation. For the second Frost Advisory, temperatures as low as 32 will result in frost formation. * WHERE...Southern Salinas Valley/Arroyo Seco and Lake San Antonio. * WHEN...For the first Frost Advisory, until 9 AM PDT this morning. For the second Frost Advisory, from 2 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. && $$ For more information from the National Weather Service visit http://weather.gov/mtr
4 follow-up statements
751 WWUS76 KMTR 121425 NPWMTR URGENT - WEATHER MESSAGE National Weather Service San Francisco Bay Area 725 AM PDT Tue Oct 12 2021 CAZ516-122230- /O.CAN.KMTR.FR.Y.0003.000000T0000Z-211012T1600Z/ /O.CON.KMTR.FR.Y.0004.211013T0900Z-211013T1600Z/ Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Including the cities of Greenfield and King City 725 AM PDT Tue Oct 12 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 2 AM TO 9 AM PDT WEDNESDAY... ...FROST ADVISORY FOR TUESDAY MORNING IS CANCELLED... * WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...Southern Salinas Valley/Arroyo Seco and Lake San Antonio. * WHEN...From 2 AM to 9 AM PDT Wednesday. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ For more information from the National Weather Service visit http://weather.gov/mtr
919 WWUS76 KMTR 122224 NPWMTR URGENT - WEATHER MESSAGE National Weather Service San Francisco Bay Area 324 PM PDT Tue Oct 12 2021 CAZ516-131200- /O.CON.KMTR.FR.Y.0004.211013T0900Z-211013T1600Z/ Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Including the cities of Greenfield and King City 324 PM PDT Tue Oct 12 2021 ...FROST ADVISORY REMAINS IN EFFECT FROM 2 AM TO 9 AM PDT WEDNESDAY... * WHAT...Temperatures as low as 32 will result in frost formation. * WHERE...Southern Salinas Valley/Arroyo Seco and Lake San Antonio. * WHEN...From 2 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. && $$ For more information from the National Weather Service visit http://weather.gov/mtr
254 WWUS76 KMTR 131119 NPWMTR URGENT - WEATHER MESSAGE National Weather Service San Francisco Bay Area 419 AM PDT Wed Oct 13 2021 CAZ516-131600- /O.CON.KMTR.FR.Y.0004.000000T0000Z-211013T1600Z/ Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Including the cities of Greenfield and King City 419 AM PDT Wed Oct 13 2021 ...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM PDT THIS MORNING... * WHAT...Temperatures as low as 34 could result in frost formation. * WHERE...Southern Salinas Valley/Arroyo Seco and Lake San Antonio...especially around King City and southward. * WHEN...Until 9 AM PDT this morning. * IMPACTS...Frost could kill sensitive outdoor vegetation if left uncovered. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ For more information from the National Weather Service visit http://weather.gov/mtr
638 WWUS76 KMTR 131548 NPWMTR URGENT - WEATHER MESSAGE National Weather Service San Francisco Bay Area 848 AM PDT Wed Oct 13 2021 CAZ516-131700- /O.EXP.KMTR.FR.Y.0004.000000T0000Z-211013T1600Z/ Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Including the cities of Greenfield and King City 848 AM PDT Wed Oct 13 2021 ...FROST ADVISORY WILL EXPIRE AT 9 AM PDT THIS MORNING... Temperatures will continue to warm through the morning ending the threat for frost development. $$ For more information from the National Weather Service visit http://weather.gov/mtr
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Oct 12, 2:50 AM PDT | Small Craft Advisory | MTR | 4 days | |
| Oct 12, 2:29 PM PDT | Small Craft Advisory | MTR | 37 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.