Alert archive / California / Freeze Warnings in 2018
Freeze Warning 1, NWS San Francisco Bay Area, CA
NWS San Francisco Bay Area, CA issued this freeze warning at Feb 18, 2018, 9:13 AM PST for 10 counties in California. It took effect at Feb 20, 2018, 12:00 AM PST. It was in force for 9 hr. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Feb 18, 2018, 9:13 AM PST (17:13 UTC)
- In effect from
- Feb 20, 2018, 12:00 AM PST
- Expired
- Feb 20, 2018, 9:00 AM PST
- In force
- 9 hr
- Issued by
- NWS San Francisco Bay Area, CA
Counties Alameda County, CA, Contra Costa County, CA, Marin County, CA, Monterey County, CA, Napa 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), 42 km from the middle of the area, began a volume at 17:10 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.
What forecasters said that day
The local office's own words before this freeze warning 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 freeze warning went out at Feb 18, 9:05 AM PST, 8 minutes earlier.
Area forecast discussion, Feb 18, 9:05 AM PST, 8 minutes before
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</html>Hazardous weather outlook, Feb 17, 9:20 PM PST, 11 hours 53 minutes before
Hazardous Weather Outlook National Weather Service San Francisco CA 920 PM PST Sat Feb 17 2018 CAZ006-505>513-516>518-528>530-181400- San Francisco- Coastal North Bay Including Point Reyes National Seashore- North Bay Interior Valleys-North Bay Mountains- San Francisco Bay Shoreline-San Francisco Peninsula Coast- East Bay Interior Valleys-East Bay Hills and the Diablo Range- Santa Cruz Mountains-Santa Clara Valley Including San Jose- Southern Salinas Valley/Arroyo Seco and Lake San Antonio- Santa Lucia Mountains and Los Padres National Forest- Mountains Of San Benito County And Interior Monterey County Including Pinnacles National Park- Northern Salinas Valley/Hollister Valley and Carmel Valley- Northern Monterey Bay-Southern Monterey Bay and Big Sur Coast- 920 PM PST Sat Feb 17 2018 This hazardous weather outlook is for the San Francisco Bay Area and Monterey Bay Area. .DAY ONE...Saturday night Mild weather conditions will continue with seasonal temperatures overnight. .DAYS TWO THROUGH SEVEN...Sunday through Friday A strong cold front is forecast to sweep across the region on Sunday morning. This cold front will potentially result in the following weather hazards: * Locally strong and gusty west to northwest winds from Sunday afternoon through Monday. The strongest winds are expected near the coast where wind gusts up to 40 mph are possible. At this time winds are expected to remain just below wind advisory levels except perhaps at a few isolated windy spots along the coast. * Most forecast models indicate the potential for post-frontal showers across portions of the region from Sunday night into Monday, mainly along coastal areas and in the Santa Cruz Mountains and Santa Lucia Mountains. Snow levels are forecast to drop as low as 1,500 feet on Sunday night and as low as 1,000 feet on Monday, or perhaps even lower. The greatest potential for snow accumulation will be in the Santa Cruz Mountains where 1 to 3 inches of snow accumulation is possible, and in the Santa Lucia Mountains of northwest Monterey County where 2 to 6 inches of snowfall will be possible. Winter Weather Advisories may be issued once forecast confidence increases regarding snow amounts. All other mountain areas including the North Bay Mountains and East Bay Hills are expected to see no precipitation or just a dusting of snow. * In wake of the frontal passage, one of the coldest air masses in recent years will settle in over the region. As winds subside Monday night into Tuesday morning, overnight temperatures will likely fall below freezing across most inland areas and potentially even in some coastal locations. A Freeze Watch is in effect for all inland portions of the San Francisco and Monterey Bay Areas late Monday night into Tuesday morning. Earlier it appeared that Tuesday night could be as cold, or even colder, as Monday night. However, recent models indicate that cloud cover will increase on Tuesday night ahead of another incoming weather system. That cloud cover should result in moderating temperatures on Tuesday night, except perhaps for the far southern portion of the region.
The office that day
Everything else NWS San Francisco Bay Area, CA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 17, 7:16 PM PST | Freeze Watch | MTR | Alameda, Contra Costa, Marin, Monterey, Napa, San Benito and 4 more | 14 hr |
| Feb 18, 8:43 AM PST | Gale Warning | MTR | 36 hr | |
| Feb 18, 1:36 PM PST | Winter Weather Advisory | MTR | Monterey, San Mateo, Santa Clara, Santa Cruz | 20 hr |
Nearby
Freeze Warnings in California, 2018Every freeze warning in 2018
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; radar from the NEXRAD Level II archive.