Alert archive / Maryland / Severe Thunderstorm Warnings

Severe Thunderstorm Warnings in Maryland, 2013

167 severe thunderstorm warnings in 2013. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of severe thunderstorm warnings reaches back to 1986.

Severe Thunderstorm Warnings by county

Each county as a circle sized by its count in 2013. Tap one for its archive.

Severe Thunderstorm Warnings
167
Busiest month
June76 severe thunderstorm warnings
Busiest day
June 28, 201324 severe thunderstorm warnings

Over time

By month

Warning verification

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

117 of 167 severe thunderstorm warnings covering Maryland in 2013 had a qualifying storm report inside them; 201 of 280 hail, wind and damage reports fell inside a warning, on average 22 minutes after it went out.

Maryland, 2013

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Severe thunderstorm warnings16711730%28072%22 min

Each office's whole area, 2013

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Philadelphia/Mount Holly: severe thunderstorm warnings1276946%21273%24 min
NWS Pittsburgh, PA: severe thunderstorm warnings26222315%74684%24 min
NWS Baltimore/Washington: severe thunderstorm warnings21014133%49574%21 min
NWS Wakefield, VA: severe thunderstorm warnings977820%28784%21 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.

IssuedProductOfficeCountiesLasted
Jan 30, 11:09 AM ESTSevere Thunderstorm WarningPBZGarrett66 min
Jan 30, 7:41 PM ESTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Charles, Howard, Montgomery, Prince George's and 1 more49 min
Jan 31, 1:52 AM ESTSevere Thunderstorm WarningLWXCalvert, Saint Mary's53 min
Jan 31, 1:54 AM ESTSevere Thunderstorm WarningPHICaroline, Cecil, Kent, Queen Anne's, Talbot66 min
Apr 12, 6:51 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Howard, Montgomery39 min
Apr 12, 7:04 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Howard, Montgomery41 min
Apr 19, 6:31 PM EDTSevere Thunderstorm WarningLWXCharles44 min
Apr 19, 6:48 PM EDTSevere Thunderstorm WarningLWXCharles, Montgomery, Prince George's42 min
Apr 19, 7:00 PM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Prince George's, Saint Mary's45 min
Apr 19, 7:18 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's42 min
Apr 19, 7:22 PM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Prince George's, Saint Mary's38 min
Apr 19, 7:29 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot61 min
Apr 19, 7:44 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, City of Baltimore46 min
Apr 19, 8:00 PM EDTSevere Thunderstorm WarningLWXCalvert, Saint Mary's30 min
Apr 19, 8:08 PM EDTSevere Thunderstorm WarningPHICecil52 min
Apr 24, 4:59 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington31 min
May 8, 3:39 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Howard, City of Baltimore36 min
May 8, 4:42 PM EDTSevere Thunderstorm WarningLWXMontgomery48 min
May 11, 4:48 PM EDTSevere Thunderstorm WarningLWXHarford42 min
May 11, 5:18 PM EDTSevere Thunderstorm WarningPHICecil42 min
May 11, 5:49 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Prince George's41 min
May 22, 5:25 PM EDTSevere Thunderstorm WarningLWXWashington50 min
May 22, 6:23 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington37 min
May 23, 5:44 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington61 min
May 23, 6:16 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington44 min
May 23, 10:43 PM EDTSevere Thunderstorm WarningLWXCharles, Montgomery, Prince George's47 min
May 28, 6:37 PM EDTSevere Thunderstorm WarningLWXPrince George's38 min
May 28, 7:31 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's, Saint Mary's44 min
May 28, 7:58 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's47 min
May 28, 8:43 PM EDTSevere Thunderstorm WarningPHICaroline, Talbot92 min
Jun 2, 3:08 PM EDTSevere Thunderstorm WarningLWXWashington37 min
Jun 10, 5:22 PM EDTSevere Thunderstorm WarningLWXWashington23 min
Jun 10, 5:42 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington48 min
Jun 13, 12:14 AM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Prince George's, Saint Mary's31 min
Jun 13, 1:09 AM EDTSevere Thunderstorm WarningPBZGarrett66 min
Jun 13, 6:26 AM EDTSevere Thunderstorm WarningLWXAllegany, Washington49 min
Jun 13, 6:53 AM EDTSevere Thunderstorm WarningLWXWashington52 min
Jun 13, 7:26 AM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Washington49 min
Jun 13, 7:52 AM EDTSevere Thunderstorm WarningLWXFrederick, Washington38 min
Jun 13, 8:07 AM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Frederick, Harford38 min
Jun 13, 8:40 AM EDTSevere Thunderstorm WarningLWXBaltimore, Harford65 min
Jun 13, 8:40 AM EDTSevere Thunderstorm WarningPHICecil, Kent50 min
Jun 13, 9:03 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Harford, Howard, City of Baltimore42 min
Jun 13, 9:18 AM EDTSevere Thunderstorm WarningPHICecil57 min
Jun 13, 9:26 AM EDTSevere Thunderstorm WarningLWXAnne Arundel, Prince George's49 min
Jun 13, 9:29 AM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's31 min
Jun 13, 9:55 AM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot35 min
Jun 13, 2:56 PM EDTSevere Thunderstorm WarningLWXMontgomery49 min
Jun 13, 3:29 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery, Prince George's61 min
Jun 13, 3:53 PM EDTSevere Thunderstorm WarningAKQDorchester, Somerset, Wicomico67 min
Jun 13, 4:06 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Howard, Prince George's, City of Baltimore54 min
Jun 13, 4:14 PM EDTSevere Thunderstorm WarningAKQSomerset31 min
Jun 13, 4:27 PM EDTSevere Thunderstorm WarningAKQDorchester, Somerset, Wicomico, Worcester48 min
Jun 13, 4:37 PM EDTSevere Thunderstorm WarningPHICaroline, Kent, Queen Anne's, Talbot68 min
Jun 13, 4:44 PM EDTSevere Thunderstorm WarningAKQSomerset46 min
Jun 13, 5:33 PM EDTSevere Thunderstorm WarningAKQWorcester27 min
Jun 17, 4:06 PM EDTSevere Thunderstorm WarningPHICecil69 min
Jun 24, 12:54 PM EDTSevere Thunderstorm WarningLWXAllegany51 min
Jun 24, 1:19 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington56 min
Jun 24, 1:22 PM EDTSevere Thunderstorm WarningPHICecil53 min
Jun 24, 2:18 PM EDTSevere Thunderstorm WarningPHICecil57 min
Jun 24, 3:10 PM EDTSevere Thunderstorm WarningLWXMontgomery50 min
Jun 24, 3:51 PM EDTSevere Thunderstorm WarningLWXFrederick, Montgomery39 min
Jun 24, 4:06 PM EDTSevere Thunderstorm WarningLWXCharles39 min
Jun 24, 4:27 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's48 min
Jun 24, 6:08 PM EDTSevere Thunderstorm WarningLWXSaint Mary's37 min
Jun 25, 8:57 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington48 min
Jun 25, 9:10 PM EDTSevere Thunderstorm WarningPBZGarrett50 min
Jun 25, 9:20 PM EDTSevere Thunderstorm WarningLWXCarroll, Frederick, Washington40 min
Jun 25, 9:37 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington38 min
Jun 25, 9:55 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Carroll, Frederick, Harford, Howard and 1 more65 min
Jun 25, 10:06 PM EDTSevere Thunderstorm WarningLWXFrederick, Howard, Montgomery54 min
Jun 25, 10:28 PM EDTSevere Thunderstorm WarningPHICecil, Kent62 min
Jun 25, 10:33 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Charles, Montgomery, Prince George's57 min
Jun 25, 11:01 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot59 min
Jun 26, 2:46 PM EDTSevere Thunderstorm WarningLWXCharles44 min
Jun 26, 3:20 PM EDTSevere Thunderstorm WarningLWXCharles55 min
Jun 26, 3:50 PM EDTSevere Thunderstorm WarningLWXCharles, Saint Mary's55 min
Jun 26, 4:50 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Howard, City of Baltimore40 min
Jun 27, 1:51 PM EDTSevere Thunderstorm WarningLWXWashington24 min
Jun 28, 2:35 PM EDTSevere Thunderstorm WarningPBZGarrett70 min
Jun 28, 2:43 PM EDTSevere Thunderstorm WarningLWXMontgomery32 min
Jun 28, 3:09 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll36 min
Jun 28, 3:19 PM EDTSevere Thunderstorm WarningPHICecil41 min
Jun 28, 3:26 PM EDTSevere Thunderstorm WarningPBZGarrett34 min
Jun 28, 3:31 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's29 min
Jun 28, 3:33 PM EDTSevere Thunderstorm WarningLWXCharles27 min
Jun 28, 3:37 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's23 min
Jun 28, 3:45 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's30 min
Jun 28, 3:50 PM EDTSevere Thunderstorm WarningLWXCharles25 min
Jun 28, 3:53 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Prince George's37 min
Jun 28, 4:12 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's33 min
Jun 28, 4:14 PM EDTSevere Thunderstorm WarningLWXCharles, Saint Mary's31 min
Jun 28, 4:20 PM EDTSevere Thunderstorm WarningPHICecil55 min
Jun 28, 4:29 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's46 min
Jun 28, 4:38 PM EDTSevere Thunderstorm WarningLWXCharles, Saint Mary's22 min
Jun 28, 4:50 PM EDTSevere Thunderstorm WarningPHICecil55 min
Jun 28, 4:52 PM EDTSevere Thunderstorm WarningLWXCalvert, Saint Mary's38 min
Jun 28, 5:14 PM EDTSevere Thunderstorm WarningPHICaroline, Queen Anne's, Talbot46 min
Jun 28, 5:41 PM EDTSevere Thunderstorm WarningLWXCalvert, Saint Mary's19 min
Jun 28, 6:07 PM EDTSevere Thunderstorm WarningAKQDorchester, Wicomico38 min
Jun 28, 6:09 PM EDTSevere Thunderstorm WarningPHICaroline96 min
Jun 28, 6:30 PM EDTSevere Thunderstorm WarningAKQSomerset, Worcester45 min
Jun 28, 7:52 PM EDTSevere Thunderstorm WarningAKQSomerset, Wicomico, Worcester53 min
Jun 28, 8:06 PM EDTSevere Thunderstorm WarningAKQDorchester39 min
Jun 30, 12:34 PM EDTSevere Thunderstorm WarningPHIKent, Queen Anne's41 min
Jul 7, 12:27 PM EDTSevere Thunderstorm WarningPBZGarrett63 min
Jul 7, 2:13 PM EDTSevere Thunderstorm WarningLWXAllegany, Washington47 min
Jul 7, 3:46 PM EDTSevere Thunderstorm WarningLWXWashington44 min
Jul 7, 4:04 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington41 min
Jul 7, 5:04 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Frederick41 min
Jul 10, 6:56 PM EDTSevere Thunderstorm WarningPBZGarrett49 min
Jul 10, 7:28 PM EDTSevere Thunderstorm WarningPBZGarrett47 min
Jul 10, 8:13 PM EDTSevere Thunderstorm WarningPBZGarrett62 min
Jul 18, 4:03 PM EDTSevere Thunderstorm WarningLWXAnne Arundel42 min
Jul 18, 4:41 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, City of Baltimore49 min
Jul 19, 5:09 PM EDTSevere Thunderstorm WarningLWXMontgomery51 min
Jul 19, 5:21 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Howard39 min
Jul 19, 5:59 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, Howard61 min
Jul 19, 6:28 PM EDTSevere Thunderstorm WarningLWXWashington62 min
Jul 20, 12:28 PM EDTSevere Thunderstorm WarningLWXFrederick, Washington47 min
Jul 20, 8:18 PM EDTSevere Thunderstorm WarningLWXMontgomery27 min
Jul 20, 8:49 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery41 min
Jul 20, 10:17 PM EDTSevere Thunderstorm WarningPHICecil, Kent, Queen Anne's58 min
Jul 28, 10:31 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Harford44 min
Jul 28, 11:32 PM EDTSevere Thunderstorm WarningLWXHarford28 min
Jul 28, 11:54 PM EDTSevere Thunderstorm WarningPHICecil51 min
Aug 1, 9:53 PM EDTSevere Thunderstorm WarningPHIKent, Queen Anne's67 min
Aug 7, 9:03 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll42 min
Aug 9, 5:37 PM EDTSevere Thunderstorm WarningLWXCharles38 min
Aug 9, 6:51 PM EDTSevere Thunderstorm WarningLWXCalvert, Saint Mary's39 min
Aug 9, 7:14 PM EDTSevere Thunderstorm WarningLWXCharles, Saint Mary's46 min
Aug 9, 7:27 PM EDTSevere Thunderstorm WarningLWXCalvert, Charles, Saint Mary's63 min
Aug 9, 8:32 PM EDTSevere Thunderstorm WarningAKQSomerset, Wicomico, Worcester58 min
Aug 13, 5:51 AM EDTSevere Thunderstorm WarningLWXBaltimore, Harford54 min
Aug 13, 6:23 AM EDTSevere Thunderstorm WarningPHICecil67 min
Aug 13, 7:57 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's48 min
Aug 21, 6:56 PM EDTSevere Thunderstorm WarningLWXAllegany49 min
Aug 22, 12:06 AM EDTSevere Thunderstorm WarningLWXSaint Mary's24 min
Sep 2, 8:33 PM EDTSevere Thunderstorm WarningPBZGarrett42 min
Sep 12, 12:46 PM EDTSevere Thunderstorm WarningLWXBaltimore, Howard, City of Baltimore44 min
Sep 12, 1:56 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, City of Baltimore49 min
Sep 12, 2:27 PM EDTSevere Thunderstorm WarningLWXAnne Arundel48 min
Sep 12, 3:45 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery, Prince George's45 min
Sep 12, 4:19 PM EDTSevere Thunderstorm WarningLWXMontgomery, Prince George's41 min
Sep 12, 4:27 PM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Frederick48 min
Sep 12, 6:21 PM EDTSevere Thunderstorm WarningPHITalbot39 min
Oct 7, 11:42 AM EDTSevere Thunderstorm WarningLWXCharles, Prince George's48 min
Oct 7, 1:05 PM EDTSevere Thunderstorm WarningPHICecil25 min
Oct 7, 2:18 PM EDTSevere Thunderstorm WarningPHICaroline, Talbot57 min
Nov 1, 3:31 AM EDTSevere Thunderstorm WarningPBZGarrett44 min
Nov 1, 4:11 AM EDTSevere Thunderstorm WarningPBZGarrett34 min
Nov 1, 4:27 AM EDTSevere Thunderstorm WarningLWXAllegany63 min
Nov 1, 5:28 AM EDTSevere Thunderstorm WarningLWXAllegany, Washington62 min
Nov 1, 6:16 AM EDTSevere Thunderstorm WarningLWXFrederick, Washington44 min
Nov 1, 7:39 AM EDTSevere Thunderstorm WarningLWXBaltimore, Carroll, Harford51 min
Nov 1, 8:27 AM EDTSevere Thunderstorm WarningPHICecil63 min
Nov 1, 8:29 AM EDTSevere Thunderstorm WarningLWXBaltimore, Harford, City of Baltimore46 min
Nov 17, 10:25 PM ESTSevere Thunderstorm WarningPBZGarrett65 min
Nov 17, 11:04 PM ESTSevere Thunderstorm WarningPBZGarrett56 min
Nov 17, 11:25 PM ESTSevere Thunderstorm WarningLWXAllegany65 min
Nov 18, 12:16 AM ESTSevere Thunderstorm WarningLWXAllegany, Washington59 min
Nov 18, 2:28 AM ESTSevere Thunderstorm WarningPHICecil62 min
Nov 18, 2:46 AM ESTSevere Thunderstorm WarningPHICaroline, Cecil, Kent, Queen Anne's, Talbot59 min
Nov 18, 3:39 AM ESTSevere Thunderstorm WarningPHICaroline, Talbot66 min
Dec 22, 3:26 AM ESTSevere Thunderstorm WarningPBZGarrett49 min
Dec 22, 4:04 AM ESTSevere Thunderstorm WarningLWXAllegany41 min

By county

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

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20122014

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.