Alert archive / California / Frost Advisories in 2023
Frost Advisory 7, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this frost advisory at Feb 21, 2023, 2:42 AM PST for 10 counties in California. It took effect at Feb 23, 2023, 12:00 AM PST. It was in force for 9 hr.
The area
The counties it named.
The facts
- Issued
- Feb 21, 2023, 2:42 AM PST (10:42 UTC)
- In effect from
- Feb 23, 2023, 12:00 AM PST
- Expired
- Feb 23, 2023, 9:00 AM PST
- In force
- 9 hr
- Issued by
- NWS San Francisco Bay Area, CA
Counties Alameda County, CA, City and County of San Francisco, CA, Contra Costa County, CA, Marin County, CA, Monterey County, CA, San Benito County, CA, San Mateo County, CA, Santa Clara County, CA, Santa Cruz County, CA, Sonoma County, CA
The radar
The San Francisco radar (KMUX), 35 km from the middle of the area, began a volume at 10:48 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
Vandenberg AFB, CA (KVBG), launched 00:00Z, 10.7 hours before the alert went out and 332 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
- 2769 m above ground
- 0-6 km bulk shear
- 47 kt
- 0-1 km storm-relative helicity
- 77 m²/s²
- 0-3 km storm-relative helicity
- 85 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
What forecasters said that day
The local office's own words before this frost advisory went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS San Francisco Bay Area, CA wrote its last area forecast discussion before this frost advisory went out at Feb 20, 9:41 PM PST, 5 hours 1 minute earlier.
Area forecast discussion, Feb 20, 9:41 PM PST, 5 hours 1 minute before
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</html>The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 20, 9:58 PM PST | Beach Hazards Statement | MTR | Santa Cruz | 42 hr |
| Feb 20, 9:58 PM PST | High Surf Advisory | MTR | Marin, Monterey, City and County of San Francisco, San Mateo, Santa Cruz, Sonoma | 42 hr |
| Feb 21, 2:42 AM PST | Freeze Watch | MTR | Alameda, Contra Costa, Marin, Monterey, Napa, San Benito and 4 more | 24 hr |
| Feb 21, 2:57 AM PST | Winter Storm Watch | MTR | Monterey, San Benito, San Mateo, Santa Clara, Santa Cruz | 11 hr |
| Feb 21, 3:50 AM PST | High Wind Warning | MTR | Marin, Monterey, San Benito, City and County of San Francisco, San Mateo, Santa Cruz and 1 more | 29 hr |
| Feb 21, 1:17 PM PST | Frost Advisory | MTR | Marin, Napa, Sonoma | 20 hr |
| Feb 21, 1:57 PM PST | Winter Weather Advisory | MTR | Monterey, San Benito, San Mateo, Santa Clara, Santa Cruz, Sonoma | 53 hr |
Nearby
Frost Advisories in California, 2023Every frost advisory in 2023
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.