Alert archive / California / Mariposa County

Weather alerts in Mariposa County, California, 2008

8 weather alerts in 2008, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Mariposa County and its neighbors

Each county as a circle sized by its count in 2008. Tap one for its archive.

Alerts
8
Warnings
0
Watches
1
Advisories
1
Busiest month
January4 alerts
Busiest day
January 24, 20082 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Mariposa County, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings010%
Flash flood warnings00

Each office's whole area, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS San Francisco Bay Area, CA: severe thunderstorm warnings30100%10%
NWS San Francisco Bay Area, CA: flash flood warnings50100%0
NWS Los Angeles, CA: tornado warnings40100%10%
NWS Los Angeles, CA: severe thunderstorm warnings80100%10%
NWS Los Angeles, CA: flash flood warnings461176%1984%86 min
NWS Hanford, CA: tornado warnings010%
NWS Hanford, CA: severe thunderstorm warnings16475%1050%18 min
NWS Hanford, CA: flash flood warnings15660%1479%81 min
NWS San Diego, CA: tornado warnings60100%40%
NWS San Diego, CA: severe thunderstorm warnings12283%650%29 min
NWS San Diego, CA: flash flood warnings561671%4871%103 min
NWS Reno, NV: tornado warnings6267%2100%15 min
NWS Reno, NV: severe thunderstorm warnings46296%1828%20 min
NWS Reno, NV: flash flood warnings8275%933%17 min
NWS Phoenix, AZ: severe thunderstorm warnings1412582%5271%22 min
NWS Phoenix, AZ: flash flood warnings381268%2868%93 min
NWS Medford, OR: severe thunderstorm warnings60100%20%
NWS Sacramento, CA: severe thunderstorm warnings10100%10%
NWS Sacramento, CA: flash flood warnings30100%10%
NWS Las Vegas, NV: tornado warnings10100%0
NWS Las Vegas, NV: severe thunderstorm warnings64592%2442%29 min
NWS Las Vegas, NV: flash flood warnings861978%5659%36 min

An office's figures cover every county it serves, including across state lines.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

The alerts

Every alert, in the order issued. Times are local, Pacific Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 24, 10:26 AM PSTMesoscale DiscussionSPC3 hr
Jan 24, 1:57 PM PSTMesoscale DiscussionSPC3 hr
Jan 27, 12:48 PM PSTSevere Thunderstorm WatchSPC5 hr
Jan 27, 4:06 PM PSTMesoscale DiscussionSPC54 min
May 27, 3:12 PM PDTRiver Flood StatementHNX6 hr
May 27, 5:30 PM PDTRiver Flood StatementHNX4 hr
Jul 14, 3:36 PM PDTAreal Flood AdvisoryHNX4 hr
Dec 15, 3:00 AM PSTMesoscale DiscussionSPC4 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20072009

Sources

National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.