Alert archive / Missouri

Weather alerts in Missouri, 2012

2,326 weather alerts in 2012, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.

Weather alerts by county

Each county as a circle sized by its count in 2012. Tap one for its archive.

Alerts
2,326
Warnings
1,156
Watches
117
Advisories
296
Busiest month
March367 alerts
Busiest day
February 29, 201289 alerts

Over time

By month

Warning verification

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

20 of 86 tornado warnings covering Missouri in 2012 had a tornado report inside them; 28 of 41 tornado reports fell inside a warning, on average 18 minutes after it went out.

Missouri, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings862077%4168%18 min
Severe thunderstorm warnings80040450%97178%20 min
Flash flood warnings663547%6190%146 min

Each office's whole area, 2012

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS St. Louis, MO: tornado warnings27678%2055%11 min
NWS St. Louis, MO: severe thunderstorm warnings34616353%60181%22 min
NWS St. Louis, MO: flash flood warnings28968%1788%144 min
NWS Memphis, TN: tornado warnings761186%2268%14 min
NWS Memphis, TN: severe thunderstorm warnings48220158%46872%22 min
NWS Memphis, TN: flash flood warnings641675%3982%48 min
NWS Paducah, KY: tornado warnings842175%4161%14 min
NWS Paducah, KY: severe thunderstorm warnings45016563%47865%18 min
NWS Paducah, KY: flash flood warnings16756%1794%117 min
NWS Springfield, MO: tornado warnings28968%2181%21 min
NWS Springfield, MO: severe thunderstorm warnings32819840%46578%21 min
NWS Springfield, MO: flash flood warnings311939%3692%172 min
NWS Omaha, NE: tornado warnings19574%1921%19 min
NWS Omaha, NE: severe thunderstorm warnings22512445%23081%16 min
NWS Omaha, NE: flash flood warnings14750%1479%36 min
NWS Quad Cities, IA: tornado warnings4175%475%23 min
NWS Quad Cities, IA: severe thunderstorm warnings876426%26574%30 min
NWS Quad Cities, IA: flash flood warnings11464%1080%85 min
NWS Kansas City, MO: tornado warnings3233%475%4 min
NWS Kansas City, MO: severe thunderstorm warnings1115055%13766%15 min
NWS Kansas City, MO: flash flood warnings8625%888%41 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

2,326 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.

By product

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

By county

Every county with at least one alert. A county page lists each alert that covered it.

75 more counties

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20112013

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.