Alert archive / Virginia / Roanoke County

Weather alerts in Roanoke County, Virginia, 2020

166 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Roanoke County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts
166
Warnings
46
Watches
28
Advisories
51
Busiest month
April27 alerts
Busiest day
February 7, 20207 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 1 tornado warnings covering Roanoke County in 2020 had a tornado report inside them.

Roanoke County, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings10100%0
Severe thunderstorm warnings10730%771%33 min
Flash flood warnings4250%757%217 min

Each office's whole area, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Blacksburg, VA: tornado warnings110100%10%
NWS Blacksburg, VA: severe thunderstorm warnings17513423%44774%20 min
NWS Blacksburg, VA: flash flood warnings815335%20668%95 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, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 3, 3:30 PM ESTHigh Wind WatchRNK12 hr
Jan 4, 3:42 AM ESTHigh Wind WarningRNK30 hr
Jan 6, 3:35 AM ESTWinter Weather AdvisoryRNK34 hr
Jan 7, 8:49 AM ESTMesoscale DiscussionSPC4 hr
Jan 7, 2:07 PM ESTWind AdvisoryRNK28 hr
Jan 10, 2:43 PM ESTWind AdvisoryRNK37 hr
Jan 11, 7:37 PM ESTSevere Thunderstorm WatchSPC5 hr
Jan 11, 8:44 PM ESTSevere Thunderstorm WarningRNK61 min
Jan 11, 9:26 PM ESTSevere Thunderstorm WarningRNK64 min
Jan 11, 9:43 PM ESTSevere Thunderstorm WarningRNK62 min
Jan 15, 2:30 PM ESTWind AdvisoryRNK34 hr
Jan 17, 3:53 AM ESTWinter Weather AdvisoryRNK35 hr
Jan 23, 3:17 PM ESTWinter Weather AdvisoryRNK20 hr
Jan 24, 6:44 PM ESTSpecial Weather StatementRNK61 min
Feb 2, 9:15 AM ESTWind AdvisoryRNK15 hr
Feb 5, 4:46 AM ESTFlood WatchRNK49 hr
Feb 6, 9:40 PM ESTWind AdvisoryRNK20 hr
Feb 7, 3:35 AM ESTAreal Flood AdvisoryRNK3 hr
Feb 7, 4:30 AM ESTWinter Weather AdvisoryRNK20 hr
Feb 7, 6:27 AM ESTAreal Flood AdvisoryRNK3 hr
Feb 7, 9:37 AM ESTAreal Flood WarningRNK3 hr
Feb 7, 12:25 PM ESTAreal Flood WarningRNK6 hr
Feb 7, 1:59 PM ESTRiver Flood WarningRNK17 hr
Feb 12, 11:50 PM ESTSpecial Weather StatementRNK115 min
Feb 26, 3:36 AM ESTWind AdvisoryRNK39 hr
Feb 26, 2:49 PM ESTMesoscale DiscussionSPC116 min
Mar 5, 8:34 PM ESTWind AdvisoryRNK36 hr
Mar 30, 12:41 PM EDTRed Flag WarningRNK7 hr
Apr 6, 1:59 PM EDTMesoscale DiscussionSPC2 hr
Apr 7, 2:07 PM EDTMesoscale DiscussionSPC53 min
Apr 8, 12:39 PM EDTMesoscale DiscussionSPC96 min
Apr 8, 1:10 PM EDTSevere Thunderstorm WatchSPC7 hr
Apr 8, 3:37 PM EDTTornado WarningRNK18 min
Apr 8, 4:02 PM EDTSevere Thunderstorm WarningRNK58 min
Apr 8, 4:05 PM EDTMesoscale DiscussionSPC85 min
Apr 8, 4:42 PM EDTSevere Thunderstorm WarningRNK33 min
Apr 9, 12:50 AM EDTMesoscale DiscussionSPC115 min
Apr 9, 1:47 AM EDTWind AdvisoryRNK18 hr
Apr 9, 2:03 AM EDTSevere Thunderstorm WatchSPC3 hr
Apr 9, 3:36 AM EDTMesoscale DiscussionSPC84 min
Apr 9, 3:48 AM EDTSpecial Weather StatementRNK57 min
Apr 9, 9:27 PM EDTWind AdvisoryRNK21 hr
Apr 10, 2:31 PM EDTFreeze WarningRNK18 hr
Apr 12, 4:09 AM EDTFlash Flood WatchRNK27 hr
Apr 12, 2:18 PM EDTWind AdvisoryRNK26 hr
Apr 13, 2:14 AM EDTAreal Flood AdvisoryRNK12 hr
Apr 13, 3:47 AM EDTFlash Flood WarningRNK6 hr
Apr 13, 9:30 AM EDTRiver Flood WarningRNK35 hr
Apr 13, 9:55 AM EDTAreal Flood WarningRNK6 hr
Apr 16, 3:00 PM EDTFrost AdvisoryRNK18 hr
Apr 18, 2:37 PM EDTFrost AdvisoryRNK18 hr
Apr 21, 3:25 AM EDTWind AdvisoryRNK19 hr
Apr 24, 5:08 AM EDTSpecial Weather StatementRNK22 min
Apr 29, 4:44 AM EDTFlood WatchRNK29 hr
Apr 30, 12:13 AM EDTSpecial Weather StatementRNK47 min
May 7, 4:57 AM EDTFreeze WatchRNK22 hr
May 8, 2:53 AM EDTFreeze WarningRNK31 hr
May 8, 1:52 PM EDTFreeze WatchRNK13 hr
May 9, 3:00 AM EDTFreeze WarningRNK31 hr
May 10, 2:14 PM EDTFreeze WatchRNK13 hr
May 10, 2:14 PM EDTWind AdvisoryRNK19 hr
May 11, 2:50 AM EDTFreeze WarningRNK28 hr
May 18, 2:23 PM EDTFlash Flood WatchRNK3 days
May 19, 1:28 AM EDTAreal Flood AdvisoryRNK6 hr
May 19, 7:21 AM EDTAreal Flood AdvisoryRNK4 hr
May 20, 5:17 AM EDTAreal Flood AdvisoryRNK4 hr
May 20, 9:50 AM EDTRiver Flood WarningRNK63 hr
May 20, 11:27 AM EDTAreal Flood AdvisoryRNK4 hr
May 20, 1:18 PM EDTAreal Flood WarningRNK12 hr
May 20, 3:28 PM EDTAreal Flood WarningRNK12 hr
May 21, 3:14 AM EDTAreal Flood WarningRNK9 hr
May 21, 12:07 PM EDTAreal Flood WarningRNK12 hr
May 21, 8:07 PM EDTFlash Flood WatchRNK23 hr
May 21, 11:59 PM EDTAreal Flood WarningRNK6 hr
May 22, 3:50 AM EDTDense Fog AdvisoryRNK5 hr
May 22, 5:52 AM EDTAreal Flood WarningRNK6 hr
May 22, 11:41 AM EDTAreal Flood WarningRNK4 hr
May 23, 2:56 AM EDTDense Fog AdvisoryRNK6 hr
May 24, 1:44 PM EDTMesoscale DiscussionSPC2 hr
May 24, 3:26 PM EDTSpecial Weather StatementRNK34 min
May 24, 5:11 PM EDTAreal Flood AdvisoryRNK3 hr
May 27, 3:25 AM EDTFlash Flood WatchRNK23 hr
Jun 4, 2:14 PM EDTSevere Thunderstorm WarningRNK46 min
Jun 4, 2:43 PM EDTSevere Thunderstorm WarningRNK62 min
Jun 5, 5:08 AM EDTFlash Flood WatchRNK15 hr
Jun 5, 2:56 PM EDTSpecial Weather StatementRNK34 min
Jun 5, 3:26 PM EDTSpecial Weather StatementRNK34 min
Jun 6, 6:07 PM EDTMesoscale DiscussionSPC113 min
Jun 14, 6:58 PM EDTSpecial Weather StatementRNK62 min
Jun 14, 8:14 PM EDTAreal Flood AdvisoryRNK6 hr
Jun 17, 7:43 AM EDTAreal Flood AdvisoryRNK83 min
Jun 17, 8:12 AM EDTFlash Flood WarningRNK6 hr
Jun 17, 9:04 AM EDTAreal Flood WarningRNK5 hr
Jun 17, 9:49 AM EDTRiver Flood WarningRNK27 hr
Jun 17, 12:08 PM EDTFlash Flood WatchRNK21 hr
Jun 17, 2:16 PM EDTAreal Flood WarningRNK6 hr
Jun 17, 8:14 PM EDTAreal Flood WarningRNK17 hr
Jun 19, 2:16 PM EDTFlash Flood WarningRNK3 hr
Jun 20, 12:47 PM EDTFlash Flood WatchRNK8 hr
Jun 23, 4:42 PM EDTAreal Flood AdvisoryRNK2 hr
Jul 5, 2:39 PM EDTSpecial Weather StatementRNK36 min
Jul 17, 1:47 PM EDTMesoscale DiscussionSPC118 min
Jul 18, 2:38 PM EDTSevere Thunderstorm WarningRNK48 min
Jul 18, 3:11 PM EDTHeat AdvisoryRNK30 hr
Jul 19, 3:04 PM EDTHeat AdvisoryRNK30 hr
Jul 21, 1:00 PM EDTMesoscale DiscussionSPC2 hr
Jul 21, 3:22 PM EDTSevere Thunderstorm WarningRNK38 min
Jul 21, 10:46 PM EDTSevere Thunderstorm WarningRNK59 min
Jul 23, 1:11 PM EDTMesoscale DiscussionSPC2 hr
Jul 30, 9:15 PM EDTSpecial Weather StatementRNK30 min
Aug 2, 4:55 AM EDTFlash Flood WatchRNK50 hr
Aug 2, 2:18 PM EDTMesoscale DiscussionSPC57 min
Aug 3, 12:33 PM EDTAreal Flood AdvisoryRNK3 hr
Aug 3, 12:41 PM EDTSpecial Weather StatementRNK64 min
Aug 5, 6:37 PM EDTSpecial Weather StatementRNK23 min
Aug 5, 7:02 PM EDTSpecial Weather StatementRNK43 min
Aug 6, 2:08 PM EDTMesoscale DiscussionSPC3 hr
Aug 6, 3:29 PM EDTSpecial Weather StatementRNK31 min
Aug 12, 1:15 PM EDTMesoscale DiscussionSPC2 hr
Aug 13, 2:50 AM EDTFlash Flood WatchRNK21 hr
Aug 14, 3:48 AM EDTFlash Flood WatchRNK41 hr
Aug 19, 5:11 PM EDTAreal Flood AdvisoryRNK91 min
Aug 21, 4:15 AM EDTFlash Flood WatchRNK26 hr
Aug 22, 6:14 PM EDTSpecial Weather StatementRNK31 min
Aug 22, 7:18 PM EDTAreal Flood AdvisoryRNK117 min
Aug 23, 4:35 PM EDTSpecial Weather StatementRNK55 min
Aug 24, 6:04 AM EDTDense Fog AdvisoryRNK3 hr
Aug 25, 3:34 PM EDTSevere Thunderstorm WatchSPC7 hr
Aug 25, 7:07 PM EDTMesoscale DiscussionSPC113 min
Aug 25, 8:50 PM EDTMesoscale DiscussionSPC115 min
Aug 28, 7:50 PM EDTMesoscale DiscussionSPC2 hr
Aug 30, 7:55 PM EDTFlood WatchRNK26 hr
Aug 31, 3:10 AM EDTFlash Flood WatchRNK21 hr
Aug 31, 10:48 AM EDTAreal Flood AdvisoryRNK4 hr
Aug 31, 12:20 PM EDTFlash Flood WarningRNK2 hr
Oct 10, 4:13 AM EDTFlood WatchRNK44 hr
Oct 11, 4:43 AM EDTAreal Flood AdvisoryRNK4 hr
Oct 13, 2:32 AM EDTDense Fog AdvisoryRNK6 hr
Oct 16, 2:17 PM EDTFrost AdvisoryRNK20 hr
Oct 17, 1:59 PM EDTFrost AdvisoryRNK19 hr
Oct 28, 5:33 AM EDTFlood WatchRNK32 hr
Oct 29, 9:59 AM EDTAreal Flood AdvisoryRNK3 hr
Oct 30, 2:32 PM EDTFrost AdvisoryRNK19 hr
Nov 1, 3:33 AM ESTFreeze WarningRNK29 hr
Nov 1, 3:33 AM ESTWind AdvisoryRNK32 hr
Nov 2, 1:49 PM ESTFreeze WarningRNK17 hr
Nov 10, 1:51 PM ESTFlood WatchRNK48 hr
Nov 11, 12:22 PM ESTAreal Flood AdvisoryRNK3 hr
Nov 11, 7:45 PM ESTAreal Flood WarningRNK6 hr
Nov 11, 8:50 PM ESTAreal Flood AdvisoryRNK3 hr
Nov 12, 1:21 AM ESTAreal Flood WarningRNK15 hr
Nov 12, 1:50 AM ESTRiver Flood WarningRNK26 hr
Nov 12, 3:37 PM ESTAreal Flood WarningRNK6 hr
Nov 12, 9:32 PM ESTAreal Flood WarningRNK8 hr
Nov 14, 2:06 PM ESTWind AdvisoryRNK44 hr
Dec 4, 10:11 PM ESTSpecial Weather StatementRNK49 min
Dec 14, 2:26 PM ESTWinter Storm WatchRNK14 hr
Dec 15, 4:35 AM ESTWinter Storm WarningRNK41 hr
Dec 16, 6:36 AM ESTMesoscale DiscussionSPC4 hr
Dec 16, 7:33 AM ESTSpecial Weather StatementRNK117 min
Dec 21, 5:05 AM ESTWind AdvisoryRNK31 hr
Dec 23, 2:51 PM ESTWinter Weather AdvisoryRNK48 hr
Dec 23, 3:15 PM ESTFlash Flood WatchRNK33 hr
Dec 24, 7:31 PM ESTSpecial Weather StatementRNK89 min
Dec 24, 8:55 PM ESTSpecial Weather StatementRNK80 min
Dec 25, 3:17 PM ESTWind Chill AdvisoryRNK18 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 archive20192021

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.