Alert archive / Maryland / Frederick County

Weather alerts in Frederick County, Maryland, 2010

212 weather alerts in 2010, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Frederick County and its neighbors

Each county as a circle sized by its count in 2010. Tap one for its archive.

Alerts: 212
Warnings: 66
Watches: 36
Advisories: 37
Busiest month: April34 alerts
Busiest day: April 25, 201012 alerts

Over time

By month

Warning verification

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

1 of 4 tornado warnings covering Frederick County in 2010 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 15 minutes after it went out.

Frederick County, 2010

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	4	1	75%	1	100%	15 min
Severe thunderstorm warnings	28	25	11%	28	64%	21 min
Flash flood warnings	8	4	50%	3	100%	210 min

Each office's whole area, 2010

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Baltimore/Washington: tornado warnings	31	2	94%	4	50%	17 min
NWS Baltimore/Washington: severe thunderstorm warnings	257	198	23%	762	86%	21 min
NWS Baltimore/Washington: flash flood warnings	64	35	45%	139	92%	166 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.

Issued	Product	Office	Lasted
Jan 2, 4:15 AM EST	Wind Chill Advisory	LWX	53 hr
Jan 2, 4:21 AM EST	Wind Advisory	LWX	38 hr
Jan 7, 3:48 AM EST	Winter Weather Advisory	LWX	57 hr
Jan 21, 12:55 PM EST	Winter Weather Advisory	LWX	24 hr
Jan 23, 1:08 PM EST	Flash Flood Watch	LWX	48 hr
Jan 24, 6:06 PM EST	Wind Advisory	LWX	19 hr
Jan 25, 9:15 AM EST	Areal Flood Warning	LWX	10 hr
Jan 25, 4:18 PM EST	River Flood Warning	LWX	24 hr
Jan 25, 4:18 PM EST	River Flood Warning	LWX	54 hr
Jan 29, 11:00 AM EST	Winter Weather Advisory	LWX	38 hr
Feb 2, 3:07 AM EST	Winter Weather Advisory	LWX	26 hr
Feb 2, 12:03 PM EST	Winter Storm Warning	LWX	17 hr
Feb 3, 2:45 PM EST	Winter Storm Watch	LWX	19 hr
Feb 4, 9:59 AM EST	Winter Storm Warning	LWX	55 hr
Feb 5, 11:45 AM EST	Mesoscale Discussion	SPC	4 hr
Feb 5, 6:58 PM EST	Mesoscale Discussion	SPC	4 hr
Feb 7, 3:15 PM EST	Winter Storm Watch	LWX	35 hr
Feb 8, 3:04 PM EST	Winter Storm Warning	LWX	46 hr
Feb 10, 3:45 AM EST	Blizzard Warning	LWX	23 hr
Feb 10, 7:27 AM EST	Mesoscale Discussion	SPC	5 hr
Feb 10, 12:20 PM EST	Mesoscale Discussion	SPC	4 hr
Feb 15, 3:49 AM EST	Winter Weather Advisory	LWX	17 hr
Feb 23, 5:31 AM EST	Winter Storm Watch	LWX	55 hr
Feb 25, 9:35 AM EST	High Wind Watch	LWX	6 hr
Feb 25, 12:14 PM EST	Winter Weather Advisory	LWX	30 hr
Feb 25, 3:41 PM EST	High Wind Warning	LWX	26 hr
Feb 25, 3:41 PM EST	Wind Advisory	LWX	24 hr
Mar 10, 5:46 AM EST	Flood Watch	LWX	3 days
Mar 13, 12:28 AM EST	River Flood Warning	LWX	11 hr
Mar 13, 10:25 AM EST	Areal Flood Warning	LWX	6 hr
Mar 13, 11:42 AM EST	River Flood Warning	LWX	72 hr
Mar 13, 4:17 PM EST	Areal Flood Warning	LWX	8 hr
Mar 13, 4:38 PM EST	River Flood Warning	LWX	29 hr
Mar 14, 12:24 AM EST	Areal Flood Warning	LWX	6 hr
Mar 14, 7:19 AM EDT	Areal Flood Warning	LWX	6 hr
Mar 22, 12:44 PM EDT	Mesoscale Discussion	SPC	2 hr
Mar 22, 6:53 PM EDT	Mesoscale Discussion	SPC	3 hr
Mar 28, 1:49 PM EDT	Flood Watch	LWX	14 hr
Apr 7, 9:57 AM EDT	Red Flag Warning	LWX	9 hr
Apr 8, 5:17 PM EDT	Special Weather Statement	LWX	43 min
Apr 8, 5:30 PM EDT	Severe Thunderstorm Warning	LWX	45 min
Apr 8, 6:37 PM EDT	Mesoscale Discussion	SPC	53 min
Apr 14, 12:00 AM EDT	Dense Fog Advisory	LWX	10 hr
Apr 16, 1:32 PM EDT	Red Flag Warning	LWX	6 hr
Apr 16, 3:44 PM EDT	Special Weather Statement	LWX	61 min
Apr 16, 4:17 PM EDT	Special Weather Statement	LWX	58 min
Apr 16, 4:28 PM EDT	Severe Thunderstorm Warning	LWX	32 min
Apr 16, 4:34 PM EDT	Mesoscale Discussion	SPC	86 min
Apr 16, 6:16 PM EDT	Special Weather Statement	LWX	74 min
Apr 16, 6:20 PM EDT	Special Weather Statement	LWX	70 min
Apr 16, 6:30 PM EDT	Severe Thunderstorm Warning	LWX	30 min
Apr 16, 8:05 PM EDT	Special Weather Statement	LWX	70 min
Apr 18, 8:59 AM EDT	Freeze Watch	LWX	5 hr
Apr 22, 12:37 AM EDT	Dense Fog Advisory	LWX	8 hr
Apr 25, 10:56 AM EDT	Mesoscale Discussion	SPC	2 hr
Apr 25, 4:37 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Apr 25, 5:33 PM EDT	Severe Thunderstorm Warning	LWX	42 min
Apr 25, 5:39 PM EDT	Tornado Warning	LWX	36 min
Apr 25, 6:10 PM EDT	Severe Thunderstorm Warning	LWX	50 min
Apr 25, 6:16 PM EDT	Mesoscale Discussion	SPC	89 min
Apr 25, 6:30 PM EDT	Areal Flood Warning	LWX	3 hr
Apr 25, 7:01 PM EDT	Flash Flood Warning	LWX	3 hr
Apr 25, 7:04 PM EDT	Severe Thunderstorm Warning	LWX	41 min
Apr 25, 7:19 PM EDT	Severe Thunderstorm Warning	LWX	41 min
Apr 25, 7:31 PM EDT	Severe Thunderstorm Warning	LWX	44 min
Apr 25, 7:54 PM EDT	Severe Thunderstorm Warning	LWX	51 min
Apr 25, 8:53 PM EDT	Mesoscale Discussion	SPC	2 hr
Apr 25, 8:58 PM EDT	Special Weather Statement	LWX	32 min
Apr 25, 9:11 PM EDT	Special Weather Statement	LWX	34 min
Apr 25, 9:59 PM EDT	Flash Flood Warning	LWX	46 min
Apr 27, 1:50 PM EDT	Frost Advisory	LWX	16 hr
Apr 28, 2:05 PM EDT	Frost Advisory	LWX	19 hr
May 2, 4:45 PM EDT	Mesoscale Discussion	SPC	60 min
May 2, 5:58 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
May 2, 8:27 PM EDT	Mesoscale Discussion	SPC	63 min
May 3, 5:11 AM EDT	Special Weather Statement	LWX	49 min
May 7, 3:24 PM EDT	Wind Advisory	LWX	29 hr
May 8, 12:50 PM EDT	Red Flag Warning	LWX	7 hr
May 14, 11:56 AM EDT	Mesoscale Discussion	SPC	2 hr
May 14, 2:29 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
May 14, 6:12 PM EDT	Special Weather Statement	LWX	33 min
May 14, 6:35 PM EDT	Mesoscale Discussion	SPC	55 min
May 27, 3:20 AM EDT	Flash Flood Watch	LWX	24 hr
May 27, 11:28 AM EDT	Mesoscale Discussion	SPC	92 min
May 27, 1:23 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
May 27, 4:13 PM EDT	Mesoscale Discussion	SPC	62 min
May 27, 8:08 PM EDT	Mesoscale Discussion	SPC	97 min
May 27, 11:57 PM EDT	Special Weather Statement	LWX	33 min
Jun 3, 11:27 AM EDT	Mesoscale Discussion	SPC	93 min
Jun 3, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 3, 3:36 PM EDT	Mesoscale Discussion	SPC	54 min
Jun 3, 4:23 PM EDT	Severe Thunderstorm Warning	LWX	52 min
Jun 3, 6:28 PM EDT	Mesoscale Discussion	SPC	62 min
Jun 4, 1:09 PM EDT	Mesoscale Discussion	SPC	66 min
Jun 4, 2:39 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 4, 2:51 PM EDT	Special Weather Statement	LWX	54 min
Jun 4, 3:38 PM EDT	Severe Thunderstorm Warning	LWX	52 min
Jun 4, 3:48 PM EDT	Severe Thunderstorm Warning	LWX	42 min
Jun 4, 4:24 PM EDT	Mesoscale Discussion	SPC	66 min
Jun 4, 6:08 PM EDT	Severe Thunderstorm Warning	LWX	27 min
Jun 4, 7:03 PM EDT	Mesoscale Discussion	SPC	57 min
Jun 4, 7:08 PM EDT	Special Weather Statement	LWX	37 min
Jun 6, 11:42 AM EDT	Mesoscale Discussion	SPC	63 min
Jun 6, 12:40 PM EDT	Tornado Watch	SPC	6 hr
Jun 6, 1:18 PM EDT	Severe Thunderstorm Warning	LWX	27 min
Jun 12, 5:32 PM EDT	Special Weather Statement	LWX	28 min
Jun 16, 4:36 PM EDT	Special Weather Statement	LWX	39 min
Jun 19, 11:29 PM EDT	Special Weather Statement	LWX	46 min
Jun 22, 11:35 AM EDT	Mesoscale Discussion	SPC	25 min
Jun 22, 3:48 PM EDT	Mesoscale Discussion	SPC	27 min
Jun 24, 12:16 PM EDT	Mesoscale Discussion	SPC	89 min
Jun 24, 12:28 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jun 24, 2:34 PM EDT	Mesoscale Discussion	SPC	116 min
Jun 28, 12:26 PM EDT	Mesoscale Discussion	SPC	2 hr
Jun 28, 1:12 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 28, 3:53 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 5, 1:50 PM EDT	Heat Advisory	LWX	54 hr
Jul 5, 7:38 PM EDT	Excessive Heat Watch	LWX	9 hr
Jul 8, 5:19 PM EDT	Special Weather Statement	LWX	41 min
Jul 16, 3:10 AM EDT	Heat Advisory	LWX	15 hr
Jul 22, 2:06 PM EDT	Heat Advisory	LWX	31 hr
Jul 23, 9:14 PM EDT	Excessive Heat Warning	LWX	24 hr
Jul 23, 9:14 PM EDT	Heat Advisory	LWX	47 hr
Jul 25, 10:48 AM EDT	Mesoscale Discussion	SPC	27 min
Jul 25, 11:29 AM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 25, 12:50 PM EDT	Mesoscale Discussion	SPC	55 min
Jul 25, 2:29 PM EDT	Severe Thunderstorm Warning	LWX	61 min
Jul 25, 2:36 PM EDT	Severe Thunderstorm Warning	LWX	54 min
Jul 25, 3:25 PM EDT	Mesoscale Discussion	SPC	65 min
Jul 29, 11:44 AM EDT	Special Weather Statement	LWX	46 min
Jul 29, 12:16 PM EDT	Special Weather Statement	LWX	29 min
Jul 29, 12:31 PM EDT	Severe Thunderstorm Warning	LWX	44 min
Aug 4, 3:07 PM EDT	Heat Advisory	LWX	29 hr
Aug 4, 5:30 PM EDT	Mesoscale Discussion	SPC	30 min
Aug 4, 5:52 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Aug 4, 6:59 PM EDT	Severe Thunderstorm Warning	LWX	61 min
Aug 4, 7:48 PM EDT	Mesoscale Discussion	SPC	87 min
Aug 4, 8:00 PM EDT	Severe Thunderstorm Warning	LWX	45 min
Aug 5, 12:37 PM EDT	Mesoscale Discussion	SPC	53 min
Aug 5, 1:19 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Aug 5, 3:56 PM EDT	Mesoscale Discussion	SPC	64 min
Aug 5, 6:23 PM EDT	Mesoscale Discussion	SPC	97 min
Aug 12, 5:58 AM EDT	Special Weather Statement	LWX	47 min
Aug 12, 6:10 AM EDT	Severe Thunderstorm Warning	LWX	35 min
Aug 12, 6:28 AM EDT	Severe Thunderstorm Warning	LWX	32 min
Aug 12, 1:52 PM EDT	Mesoscale Discussion	SPC	83 min
Aug 12, 2:51 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Aug 12, 4:16 PM EDT	Special Weather Statement	LWX	44 min
Aug 12, 4:18 PM EDT	Tornado Warning	LWX	42 min
Aug 12, 4:35 PM EDT	Severe Thunderstorm Warning	LWX	55 min
Aug 12, 4:48 PM EDT	Tornado Warning	LWX	27 min
Aug 12, 5:13 PM EDT	Severe Thunderstorm Warning	LWX	62 min
Aug 12, 5:17 PM EDT	Tornado Warning	LWX	43 min
Aug 12, 9:35 PM EDT	Flash Flood Warning	LWX	3 hr
Aug 12, 10:40 PM EDT	Flash Flood Warning	LWX	2 hr
Aug 16, 2:01 PM EDT	Mesoscale Discussion	SPC	89 min
Aug 16, 2:13 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 16, 3:34 PM EDT	Special Weather Statement	LWX	26 min
Aug 16, 3:51 PM EDT	Special Weather Statement	LWX	24 min
Aug 16, 4:12 PM EDT	Special Weather Statement	LWX	33 min
Sep 7, 2:39 PM EDT	Fire Weather Watch	LWX	19 hr
Sep 8, 9:42 AM EDT	Red Flag Warning	LWX	9 hr
Sep 13, 5:36 AM EDT	Dense Fog Advisory	LWX	3 hr
Sep 16, 10:54 PM EDT	Severe Thunderstorm Warning	LWX	51 min
Sep 16, 11:51 PM EDT	Special Weather Statement	LWX	24 min
Sep 22, 2:31 PM EDT	Mesoscale Discussion	SPC	59 min
Sep 22, 2:45 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Sep 22, 7:03 PM EDT	Special Weather Statement	LWX	27 min
Sep 24, 7:30 AM EDT	Dense Fog Advisory	LWX	114 min
Sep 27, 3:43 AM EDT	Flash Flood Watch	LWX	28 hr
Sep 27, 1:03 PM EDT	Mesoscale Discussion	SPC	87 min
Sep 29, 2:21 AM EDT	Flash Flood Watch	LWX	50 hr
Sep 30, 6:39 AM EDT	Flash Flood Warning	LWX	6 hr
Sep 30, 10:29 AM EDT	Flash Flood Warning	LWX	4 hr
Sep 30, 11:12 AM EDT	River Flood Warning	LWX	5 hr
Sep 30, 11:12 AM EDT	River Flood Warning	LWX	18 hr
Sep 30, 12:22 PM EDT	Flash Flood Warning	LWX	6 hr
Sep 30, 4:40 PM EDT	Flash Flood Warning	LWX	11 hr
Oct 22, 2:27 PM EDT	Frost Advisory	LWX	19 hr
Oct 26, 2:43 PM EDT	Wind Advisory	LWX	11 hr
Oct 26, 7:19 PM EDT	Tornado Watch	SPC	12 hr
Oct 26, 11:05 PM EDT	Mesoscale Discussion	SPC	55 min
Oct 27, 12:24 AM EDT	Mesoscale Discussion	SPC	66 min
Oct 27, 9:56 PM EDT	Dense Fog Advisory	LWX	7 hr
Oct 29, 3:50 AM EDT	Freeze Watch	LWX	11 hr
Oct 29, 2:28 PM EDT	Freeze Warning	LWX	19 hr
Oct 31, 4:04 AM EDT	Freeze Watch	LWX	10 hr
Oct 31, 1:49 PM EDT	Frost Advisory	LWX	19 hr
Oct 31, 6:10 PM EDT	Freeze Warning	LWX	15 hr
Nov 1, 4:02 AM EDT	Freeze Watch	LWX	10 hr
Nov 1, 1:57 PM EDT	Freeze Warning	LWX	19 hr
Nov 16, 2:19 PM EST	Wind Advisory	LWX	25 hr
Nov 16, 11:52 PM EST	Special Weather Statement	LWX	23 min
Nov 16, 11:59 PM EST	Severe Thunderstorm Warning	LWX	46 min
Nov 17, 12:06 AM EST	Severe Thunderstorm Watch	SPC	4 hr
Nov 24, 2:06 PM EST	Winter Weather Advisory	LWX	21 hr
Nov 29, 3:20 PM EST	Flash Flood Watch	LWX	44 hr
Nov 30, 3:12 AM EST	Wind Advisory	LWX	32 hr
Dec 1, 3:48 AM EST	Tornado Watch	SPC	7 hr
Dec 1, 5:44 AM EST	Severe Thunderstorm Warning	LWX	26 min
Dec 1, 7:25 AM EST	Severe Thunderstorm Warning	LWX	35 min
Dec 1, 7:51 AM EST	Mesoscale Discussion	SPC	84 min
Dec 1, 8:03 AM EST	Severe Thunderstorm Warning	LWX	42 min
Dec 11, 2:13 PM EST	Winter Weather Advisory	LWX	22 hr
Dec 13, 2:09 AM EST	Winter Weather Advisory	LWX	7 hr
Dec 13, 10:28 AM EST	Wind Advisory	LWX	36 hr
Dec 14, 3:52 AM EST	Winter Weather Advisory	LWX	5 hr
Dec 15, 2:21 PM EST	Winter Weather Advisory	LWX	29 hr
Dec 23, 1:30 AM EST	Wind Advisory	LWX	17 hr
Dec 25, 3:09 AM EST	Winter Storm Watch	LWX	13 hr
Dec 25, 3:42 PM EST	Winter Weather Advisory	LWX	48 hr
Dec 26, 2:42 PM EST	Wind Advisory	LWX	30 hr

By product

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

Product	Alerts
Severe storms
Severe Thunderstorm Warning	28
Tornado Warning	4
Severe Thunderstorm Watch	15
Tornado Watch	3
Mesoscale Discussion	46
Special Weather Statement	27
Flooding
Areal Flood Warning	6
Flash Flood Warning	8
River Flood Warning	7
Flash Flood Watch	5
Flood Watch	2
Winter
Blizzard Warning	1
Winter Storm Warning	3
Winter Storm Watch	4
Winter Weather Advisory	12
Heat
Excessive Heat Warning	1
Excessive Heat Watch	1
Heat Advisory	5
Cold
Freeze Warning	3
Freeze Watch	4
Frost Advisory	4
Wind Chill Advisory	1
Wind and dust
High Wind Warning	1
High Wind Watch	1
Wind Advisory	10
Fire
Red Flag Warning	4
Fire Weather Watch	1
Fog and smoke
Dense Fog Advisory	5

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2009 2011

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.