Alert archive / Virginia

Weather alerts in Alleghany County, Virginia

2,837 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Alleghany County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Alerts
2,837
Warnings
628
Watches
460
Advisories
728
Busiest year
2011174 alerts
Average year
77over 37 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.

By month of the year

Warning verification

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

From 2008 to 2025, of tornado reports in Alleghany County fell inside a tornado warning, and 100% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
201130100%0
202310100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008211338%989%22 min
200912925%2100%25 min
201014137%0
2011332524%1392%16 min
2012221055%250%56 min
20139722%475%35 min
201410550%1362%15 min
2015880%560%6 min
20168538%3100%15 min
2017550%475%22 min
201811736%650%37 min
2019171418%863%21 min
202012742%30%
202111736%757%13 min
2022221723%683%22 min
2023121017%757%37 min
202411827%2100%43 min
202514843%650%8 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200810100%0
2009110%1100%27 min
2010220%580%133 min
20115420%0
201210100%0
2013110%1100%14 min
201410100%0
2016220%9100%92 min
2017110%0
2018110%20%
201910100%0
20206350%367%34 min
202110100%0
202220100%0
20245260%0
20255340%367%36 min

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

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.

By product

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

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Sep 21, 2:16 PM EDTSevere Thunderstorm WarningRNK59 min
Sep 4, 5:28 PM EDTSevere Thunderstorm WarningRNK62 min
Sep 4, 4:36 PM EDTSevere Thunderstorm WarningRNK54 min
Aug 27, 8:32 PM EDTFlash Flood WarningRNK6 hr
Aug 22, 6:31 PM EDTSevere Thunderstorm WarningRNK59 min
Aug 16, 9:23 PM EDTSevere Thunderstorm WarningRNK67 min
Aug 14, 4:08 PM EDTSevere Thunderstorm WarningRNK37 min
Aug 14, 3:40 PM EDTSevere Thunderstorm WarningRNK50 min
Aug 11, 7:10 PM EDTSevere Thunderstorm WarningRNK65 min
Aug 11, 7:49 AM EDTSevere Thunderstorm WarningRNK56 min
Aug 10, 2:57 PM EDTSevere Thunderstorm WarningRNK78 min
Jul 28, 2:08 PM EDTSevere Thunderstorm WarningRNK67 min

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

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.