Alert archive / Alabama

Weather alerts in Alabama, 2008

2,638 weather alerts in 2008, 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 2008. Tap one for its archive.

Alerts
2,638
Warnings
1,903
Watches
189
Advisories
308
Busiest month
August352 alerts
Busiest day
December 10, 2008117 alerts

Over time

By month

Warning verification

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

63 of 399 tornado warnings covering Alabama in 2008 had a tornado report inside them; 105 of 147 tornado reports fell inside a warning, on average 20 minutes after it went out.

Alabama, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings3996384%14771%20 min
Severe thunderstorm warnings95929669%97153%21 min
Flash flood warnings711875%8065%147 min

Each office's whole area, 2008

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Nashville, TN: tornado warnings591869%3992%17 min
NWS Nashville, TN: severe thunderstorm warnings1835272%15249%11 min
NWS Nashville, TN: flash flood warnings5180%250%18 min
NWS Tallahassee, FL: tornado warnings762172%5478%19 min
NWS Tallahassee, FL: severe thunderstorm warnings2067763%20055%22 min
NWS Tallahassee, FL: flash flood warnings20480%1377%58 min
NWS Huntsville, AL: tornado warnings491569%3569%19 min
NWS Huntsville, AL: severe thunderstorm warnings2426673%29243%15 min
NWS Huntsville, AL: flash flood warnings321166%5078%128 min
NWS Birmingham, AL: tornado warnings2022986%8767%18 min
NWS Birmingham, AL: severe thunderstorm warnings49418463%58556%23 min
NWS Birmingham, AL: flash flood warnings17571%1926%61 min
NWS Mobile, AL: tornado warnings1651094%1782%33 min
NWS Mobile, AL: severe thunderstorm warnings3005482%11768%19 min
NWS Mobile, AL: flash flood warnings28389%1974%212 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

2,638 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.

27 more counties

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe 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.