Alert archive / California / Stanislaus County

Weather alerts in Stanislaus County, California, 2016

8 weather alerts in 2016, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Stanislaus County and its neighbors

Each county as a circle sized by its count in 2016. Tap one for its archive.

Alerts
8
Warnings
1
Watches
1
Advisories
5
Busiest month
January3 alerts
Busiest day
April 27, 20162 alerts

Over time

By month

Warning verification

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

0 of 4 tornado reports fell inside a warning.

Stanislaus County, 2016

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings040%
Severe thunderstorm warnings10100%0
Flash flood warnings00

Each office's whole area, 2016

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Sacramento, CA: tornado warnings40100%40%
NWS Sacramento, CA: severe thunderstorm warnings13469%1155%17 min
NWS Sacramento, CA: flash flood warnings4175%1100%61 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 5, 5:10 AM PSTAreal Flood AdvisorySTO7 hr
Jan 18, 4:01 AM PSTAreal Flood AdvisorySTO6 hr
Jan 19, 5:10 AM PSTAreal Flood AdvisorySTO11 hr
Mar 9, 2:31 PM PSTFlood WatchSTO5 days
Apr 27, 12:45 PM PDTSpecial Weather StatementSTO45 min
Apr 27, 1:06 PM PDTSevere Thunderstorm WarningSTO38 min
Apr 27, 5:48 PM PDTAreal Flood AdvisorySTO3 hr
Oct 28, 10:44 AM PDTAreal Flood AdvisorySTO4 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 archive20152017

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.