Alert archive / Maryland / Harford County

Weather alerts in Harford County, Maryland, 2011

171 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Harford County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts
171
Warnings
60
Watches
19
Advisories
0
Busiest month
August38 alerts
Busiest day
June 12, 201112 alerts

Over time

By month

Warning verification

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

4 of 9 tornado warnings covering Harford County in 2011 had a tornado report inside them; 2 of 2 tornado reports fell inside a warning, on average 26 minutes after it went out.

Harford County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings9456%2100%26 min
Severe thunderstorm warnings262119%2488%26 min
Flash flood warnings15847%683%201 min

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Baltimore/Washington: tornado warnings962772%4567%11 min
NWS Baltimore/Washington: severe thunderstorm warnings44033524%96378%18 min
NWS Baltimore/Washington: flash flood warnings1709942%34184%121 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 18, 12:29 AM ESTMesoscale DiscussionSPC6 hr
Jan 26, 2:19 PM ESTMesoscale DiscussionSPC6 hr
Feb 21, 5:58 PM ESTMesoscale DiscussionSPC4 hr
Feb 25, 11:22 AM ESTSpecial Weather StatementLWX53 min
Feb 25, 11:36 AM ESTMesoscale DiscussionSPC84 min
Feb 25, 12:19 PM ESTSevere Thunderstorm WatchSPC3 hr
Feb 25, 12:22 PM ESTSpecial Weather StatementLWX38 min
Feb 25, 2:40 PM ESTMesoscale DiscussionSPC65 min
Mar 8, 6:00 PM ESTRiver Flood WarningPHI8 hr
Mar 10, 12:37 PM ESTAreal Flood WarningLWX6 hr
Mar 10, 6:29 PM ESTFlash Flood WarningLWX4 hr
Mar 11, 10:31 AM ESTRiver Flood WarningPHI65 hr
Mar 23, 6:57 PM EDTSpecial Weather StatementLWX33 min
Apr 5, 2:18 AM EDTTornado WatchSPC8 hr
Apr 5, 3:34 AM EDTMesoscale DiscussionSPC116 min
Apr 5, 4:40 AM EDTSevere Thunderstorm WarningLWX53 min
Apr 5, 8:32 AM EDTSpecial Weather StatementLWX58 min
Apr 16, 1:29 PM EDTTornado WatchSPC8 hr
Apr 16, 4:29 PM EDTMesoscale DiscussionSPC31 min
Apr 16, 6:38 PM EDTMesoscale DiscussionSPC97 min
Apr 16, 8:12 PM EDTMesoscale DiscussionSPC63 min
Apr 16, 8:18 PM EDTSevere Thunderstorm WarningLWX42 min
Apr 16, 9:16 PM EDTSpecial Weather StatementLWX29 min
Apr 17, 5:55 PM EDTRiver Flood WarningPHI26 hr
Apr 24, 2:12 PM EDTMesoscale DiscussionSPC93 min
Apr 24, 3:40 PM EDTSevere Thunderstorm WatchSPC5 hr
Apr 24, 4:43 PM EDTSevere Thunderstorm WarningLWX47 min
Apr 24, 6:10 PM EDTMesoscale DiscussionSPC65 min
Apr 24, 7:13 PM EDTSpecial Weather StatementLWX32 min
Apr 24, 7:54 PM EDTSevere Thunderstorm WarningLWX32 min
Apr 27, 1:23 PM EDTTornado WatchSPC5 hr
Apr 27, 3:55 PM EDTMesoscale DiscussionSPC65 min
Apr 27, 4:39 PM EDTMesoscale DiscussionSPC66 min
Apr 27, 6:00 PM EDTMesoscale DiscussionSPC60 min
Apr 27, 6:15 PM EDTTornado WatchSPC6 hr
Apr 27, 6:50 PM EDTMesoscale DiscussionSPC55 min
Apr 27, 7:55 PM EDTMesoscale DiscussionSPC65 min
Apr 28, 12:41 AM EDTTornado WatchSPC7 hr
Apr 28, 6:06 AM EDTSpecial Weather StatementLWX39 min
Apr 28, 7:38 AM EDTTornado WatchSPC7 hr
Apr 28, 8:14 AM EDTTornado WarningLWX11 min
Apr 28, 9:49 AM EDTTornado WarningLWX26 min
Apr 28, 9:55 AM EDTRiver Flood WarningPHI66 hr
Apr 28, 10:36 AM EDTFlash Flood WarningLWX102 min
Apr 28, 10:44 AM EDTMesoscale DiscussionSPC61 min
Apr 28, 12:15 PM EDTAreal Flood WarningLWX3 hr
May 17, 6:27 PM EDTMesoscale DiscussionSPC2 hr
May 18, 12:55 PM EDTSevere Thunderstorm WatchSPC8 hr
May 18, 2:27 PM EDTTornado WarningLWX33 min
May 18, 2:45 PM EDTFlash Flood WarningLWX3 hr
May 18, 2:57 PM EDTTornado WarningLWX33 min
May 18, 3:08 PM EDTMesoscale DiscussionSPC67 min
May 18, 4:10 PM EDTTornado WarningLWX35 min
May 18, 5:35 PM EDTAreal Flood WarningLWX3 hr
May 19, 1:56 AM EDTSpecial Weather StatementLWX34 min
May 19, 2:17 PM EDTMesoscale DiscussionSPC58 min
May 19, 4:15 PM EDTSpecial Weather StatementLWX30 min
May 19, 4:34 PM EDTSevere Thunderstorm WarningLWX41 min
May 19, 5:15 PM EDTSpecial Weather StatementLWX30 min
May 23, 10:48 AM EDTSevere Thunderstorm WatchSPC9 hr
May 23, 4:40 PM EDTMesoscale DiscussionSPC95 min
May 27, 12:57 PM EDTSevere Thunderstorm WatchSPC9 hr
May 27, 6:14 PM EDTMesoscale DiscussionSPC2 hr
May 27, 9:07 PM EDTSpecial Weather StatementLWX23 min
May 27, 9:18 PM EDTSpecial Weather StatementLWX27 min
Jun 1, 1:37 PM EDTMesoscale DiscussionSPC83 min
Jun 1, 2:24 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 1, 4:37 PM EDTSpecial Weather StatementLWX23 min
Jun 1, 4:46 PM EDTSpecial Weather StatementCTP29 min
Jun 1, 4:47 PM EDTSevere Thunderstorm WarningLWX22 min
Jun 9, 12:53 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 9, 1:45 PM EDTMesoscale DiscussionSPC90 min
Jun 9, 7:27 PM EDTSpecial Weather StatementLWX33 min
Jun 9, 8:40 PM EDTSevere Thunderstorm WarningLWX33 min
Jun 10, 5:28 PM EDTMesoscale DiscussionSPC92 min
Jun 11, 8:54 PM EDTSevere Thunderstorm WarningLWX51 min
Jun 11, 9:45 PM EDTSpecial Weather StatementLWX30 min
Jun 11, 10:13 PM EDTSpecial Weather StatementLWX47 min
Jun 11, 10:55 PM EDTSpecial Weather StatementLWX35 min
Jun 12, 12:03 PM EDTMesoscale DiscussionSPC87 min
Jun 12, 1:48 PM EDTSevere Thunderstorm WatchSPC6 hr
Jun 12, 3:45 PM EDTSevere Thunderstorm WarningLWX45 min
Jun 12, 3:52 PM EDTTornado WarningLWX23 min
Jun 12, 4:13 PM EDTTornado WarningLWX47 min
Jun 12, 4:26 PM EDTSevere Thunderstorm WarningLWX49 min
Jun 12, 4:41 PM EDTTornado WarningLWX35 min
Jun 12, 4:51 PM EDTSevere Thunderstorm WarningLWX39 min
Jun 16, 6:01 PM EDTMesoscale DiscussionSPC89 min
Jun 17, 2:15 PM EDTSpecial Weather StatementCTP30 min
Jun 22, 2:03 PM EDTMesoscale DiscussionSPC117 min
Jun 22, 2:37 PM EDTSpecial Weather StatementLWX23 min
Jul 3, 4:21 PM EDTSevere Thunderstorm WatchSPC7 hr
Jul 3, 6:03 PM EDTSevere Thunderstorm WarningLWX72 min
Jul 3, 8:19 PM EDTSpecial Weather StatementLWX41 min
Jul 7, 2:56 PM EDTSpecial Weather StatementLWX34 min
Jul 7, 5:01 PM EDTSpecial Weather StatementLWX29 min
Jul 7, 5:14 PM EDTSpecial Weather StatementLWX31 min
Jul 7, 5:36 PM EDTFlash Flood WarningLWX113 min
Jul 7, 11:21 PM EDTSevere Thunderstorm WarningLWX39 min
Jul 8, 12:34 AM EDTSpecial Weather StatementLWX26 min
Jul 8, 1:21 AM EDTSpecial Weather StatementLWX54 min
Jul 8, 11:44 AM EDTMesoscale DiscussionSPC61 min
Jul 8, 1:51 PM EDTSevere Thunderstorm WatchSPC7 hr
Jul 8, 3:49 PM EDTFlash Flood WarningLWX3 hr
Jul 8, 5:52 PM EDTMesoscale DiscussionSPC83 min
Jul 11, 5:47 PM EDTSevere Thunderstorm WatchSPC5 hr
Jul 11, 7:44 PM EDTMesoscale DiscussionSPC61 min
Jul 11, 8:15 PM EDTSevere Thunderstorm WarningLWX45 min
Jul 11, 8:56 PM EDTSevere Thunderstorm WarningLWX34 min
Jul 11, 9:17 PM EDTTornado WarningLWX19 min
Jul 19, 4:31 PM EDTSpecial Weather StatementLWX44 min
Jul 25, 1:12 PM EDTMesoscale DiscussionSPC2 hr
Jul 25, 10:58 PM EDTSpecial Weather StatementLWX62 min
Jul 29, 6:17 PM EDTMesoscale DiscussionSPC88 min
Aug 1, 3:22 PM EDTMesoscale DiscussionSPC83 min
Aug 1, 4:24 PM EDTSpecial Weather StatementLWX36 min
Aug 1, 9:45 PM EDTSpecial Weather StatementLWX30 min
Aug 3, 12:47 AM EDTSpecial Weather StatementLWX58 min
Aug 9, 8:29 PM EDTSpecial Weather StatementLWX16 min
Aug 13, 1:39 PM EDTSpecial Weather StatementLWX66 min
Aug 13, 2:07 PM EDTMesoscale DiscussionSPC113 min
Aug 13, 2:54 PM EDTSpecial Weather StatementLWX66 min
Aug 14, 4:22 AM EDTSpecial Weather StatementLWX53 min
Aug 14, 10:08 AM EDTSpecial Weather StatementLWX52 min
Aug 14, 11:28 AM EDTSpecial Weather StatementLWX62 min
Aug 14, 12:18 PM EDTFlash Flood WarningLWX2 hr
Aug 18, 5:14 PM EDTSevere Thunderstorm WarningLWX46 min
Aug 18, 5:26 PM EDTFlash Flood WarningLWX3 hr
Aug 18, 5:38 PM EDTSevere Thunderstorm WarningLWX36 min
Aug 18, 5:51 PM EDTSevere Thunderstorm WarningLWX39 min
Aug 18, 6:11 PM EDTSevere Thunderstorm WarningLWX24 min
Aug 18, 6:39 PM EDTMesoscale DiscussionSPC96 min
Aug 18, 7:28 PM EDTSevere Thunderstorm WarningLWX47 min
Aug 18, 11:53 PM EDTSevere Thunderstorm WarningLWX52 min
Aug 19, 5:19 PM EDTSevere Thunderstorm WarningLWX41 min
Aug 19, 5:51 PM EDTSpecial Weather StatementLWX24 min
Aug 19, 5:54 PM EDTSevere Thunderstorm WarningLWX51 min
Aug 19, 6:14 PM EDTSpecial Weather StatementLWX31 min
Aug 19, 6:44 PM EDTSpecial Weather StatementLWX31 min
Aug 21, 7:54 AM EDTSpecial Weather StatementLWX36 min
Aug 21, 8:04 AM EDTSpecial Weather StatementLWX26 min
Aug 21, 8:32 AM EDTSpecial Weather StatementLWX28 min
Aug 21, 11:54 AM EDTMesoscale DiscussionSPC2 hr
Aug 21, 12:52 PM EDTSevere Thunderstorm WatchSPC8 hr
Aug 21, 1:14 PM EDTSevere Thunderstorm WarningLWX46 min
Aug 21, 1:54 PM EDTSevere Thunderstorm WarningLWX51 min
Aug 21, 7:12 PM EDTMesoscale DiscussionSPC63 min
Aug 21, 7:53 PM EDTSpecial Weather StatementLWX7 min
Aug 25, 9:15 AM EDTSpecial Weather StatementLWX30 min
Aug 27, 6:24 PM EDTFlash Flood WarningLWX9 hr
Aug 27, 9:38 PM EDTFlash Flood WarningLWX6 hr
Aug 28, 3:05 AM EDTAreal Flood WarningLWX6 hr
Sep 5, 9:58 PM EDTSpecial Weather StatementLWX62 min
Sep 7, 1:58 PM EDTFlash Flood WarningLWX8 hr
Sep 7, 4:40 PM EDTRiver Flood WarningPHI4 days
Sep 7, 7:52 PM EDTSpecial Weather StatementPHI53 min
Sep 7, 10:03 PM EDTFlash Flood WarningLWX6 hr
Sep 8, 4:02 AM EDTAreal Flood WarningLWX20 hr
Sep 8, 5:54 AM EDTFlash Flood WarningLWX3 hr
Sep 8, 7:26 AM EDTFlash Flood WarningLWX3 hr
Sep 10, 7:36 PM EDTSpecial Weather StatementLWX24 min
Sep 10, 7:41 PM EDTFlash Flood WarningLWX90 min
Sep 11, 6:38 PM EDTMesoscale DiscussionSPC97 min
Sep 14, 3:22 PM EDTMesoscale DiscussionSPC53 min
Sep 14, 8:05 PM EDTSpecial Weather StatementLWX55 min
Sep 23, 3:06 PM EDTFlash Flood WarningLWX4 hr
Sep 28, 4:45 PM EDTMesoscale DiscussionSPC60 min
Oct 13, 4:28 PM EDTTornado WatchSPC4 hr
Oct 14, 11:11 AM EDTSpecial Weather StatementLWX34 min
Oct 14, 11:17 AM EDTSevere Thunderstorm WarningLWX15 min
Nov 23, 3:01 AM ESTSpecial Weather StatementLWX59 min

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 archive20102012

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.