Alert archive / Pennsylvania / Philadelphia County

Weather alerts in Philadelphia County, Pennsylvania, 2021

243 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Philadelphia County and its neighbors

Each county as a circle sized by its count in 2021. Tap one for its archive.

Alerts: 243
Warnings: 85
Watches: 34
Advisories: 61
Busiest month: July71 alerts
Busiest day: September 1, 202114 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 6 tornado warnings covering Philadelphia County in 2021 had a tornado report inside them; 1 of 2 tornado reports fell inside a warning, on average 0 minutes after it went out.

Philadelphia County, 2021

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	6	4	33%	2	50%	0 min
Severe thunderstorm warnings	42	34	19%	24	79%	20 min
Flash flood warnings	18	13	28%	25	100%	103 min

Each office's whole area, 2021

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Philadelphia/Mount Holly: tornado warnings	52	18	65%	29	76%	11 min
NWS Philadelphia/Mount Holly: severe thunderstorm warnings	324	218	33%	1,015	81%	23 min
NWS Philadelphia/Mount Holly: flash flood warnings	92	65	29%	559	96%	164 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 20, 10:42 AM EST	Special Weather Statement	PHI	63 min
Jan 25, 3:08 PM EST	Winter Weather Advisory	PHI	34 hr
Jan 29, 3:14 PM EST	Winter Storm Watch	PHI	25 hr
Jan 30, 3:44 PM EST	Winter Storm Warning	PHI	72 hr
Feb 1, 1:43 PM EST	Mesoscale Discussion	SPC	6 hr
Feb 5, 3:09 PM EST	Winter Storm Watch	PHI	12 hr
Feb 6, 3:23 AM EST	Winter Storm Warning	PHI	36 hr
Feb 10, 3:47 AM EST	Winter Weather Advisory	PHI	32 hr
Feb 12, 3:21 PM EST	Winter Weather Advisory	PHI	43 hr
Feb 13, 10:02 AM EST	Mesoscale Discussion	SPC	6 hr
Feb 14, 3:15 PM EST	Winter Weather Advisory	PHI	39 hr
Feb 16, 3:14 PM EST	Winter Storm Watch	PHI	24 hr
Feb 17, 3:43 PM EST	Winter Storm Warning	PHI	24 hr
Feb 17, 3:43 PM EST	Winter Weather Advisory	PHI	47 hr
Feb 18, 7:24 AM EST	Special Weather Statement	PHI	51 min
Feb 18, 8:24 AM EST	Special Weather Statement	PHI	66 min
Feb 18, 9:47 AM EST	Mesoscale Discussion	SPC	4 hr
Feb 18, 10:43 AM EST	Special Weather Statement	PHI	62 min
Feb 18, 12:06 PM EST	Special Weather Statement	PHI	54 min
Feb 21, 2:47 PM EST	Winter Weather Advisory	PHI	26 hr
Feb 28, 3:14 PM EST	Wind Advisory	PHI	42 hr
Feb 28, 5:20 PM EST	Areal Flood Advisory	PHI	3 hr
Mar 13, 2:44 PM EST	Wind Advisory	PHI	28 hr
Mar 13, 2:56 PM EST	Fire Weather Watch	PHI	12 hr
Mar 14, 4:22 AM EDT	Red Flag Warning	PHI	37 hr
Mar 24, 1:51 PM EDT	Areal Flood Advisory	PHI	5 hr
Mar 24, 6:26 PM EDT	Areal Flood Warning	PHI	10 hr
Mar 24, 7:09 PM EDT	Dense Fog Advisory	PHI	14 hr
Mar 25, 11:00 AM EDT	Wind Advisory	PHI	32 hr
Mar 28, 5:05 PM EDT	Severe Thunderstorm Watch	SPC	4 hr
Mar 28, 6:47 PM EDT	Severe Thunderstorm Warning	PHI	43 min
Mar 28, 7:05 PM EDT	Mesoscale Discussion	SPC	115 min
Apr 10, 3:22 AM EDT	Areal Flood Advisory	PHI	2 hr
Apr 12, 1:12 AM EDT	Areal Flood Advisory	PHI	67 min
Apr 21, 11:49 AM EDT	Mesoscale Discussion	SPC	2 hr
Apr 21, 12:28 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Apr 21, 1:10 PM EDT	Severe Thunderstorm Warning	PHI	50 min
Apr 22, 2:31 PM EDT	Frost Advisory	PHI	17 hr
Apr 29, 3:32 AM EDT	High Wind Watch	PHI	16 hr
Apr 29, 7:23 PM EDT	High Wind Warning	PHI	26 hr
Apr 29, 7:45 PM EDT	Severe Thunderstorm Warning	PHI	45 min
Apr 29, 8:05 PM EDT	Severe Thunderstorm Warning	PHI	34 min
Apr 30, 8:56 PM EDT	Wind Advisory	PHI	6 hr
May 26, 2:48 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
May 26, 4:41 PM EDT	Mesoscale Discussion	SPC	64 min
May 26, 5:27 PM EDT	Severe Thunderstorm Warning	PHI	48 min
May 26, 5:53 PM EDT	Severe Thunderstorm Warning	PHI	67 min
May 26, 6:34 PM EDT	Mesoscale Discussion	SPC	116 min
May 27, 9:45 PM EDT	Coastal Flood Advisory	PHI	58 hr
Jun 3, 9:37 AM EDT	Flash Flood Watch	PHI	12 hr
Jun 3, 1:46 PM EDT	Mesoscale Discussion	SPC	119 min
Jun 3, 2:48 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 3, 4:47 PM EDT	Mesoscale Discussion	SPC	88 min
Jun 3, 5:20 PM EDT	Areal Flood Advisory	PHI	3 hr
Jun 3, 7:09 PM EDT	Flash Flood Warning	PHI	2 hr
Jun 3, 7:13 PM EDT	Areal Flood Advisory	PHI	3 hr
Jun 4, 2:26 PM EDT	Mesoscale Discussion	SPC	94 min
Jun 4, 3:09 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Jun 4, 3:14 PM EDT	Severe Thunderstorm Warning	PHI	46 min
Jun 4, 3:16 PM EDT	Areal Flood Advisory	PHI	98 min
Jun 4, 3:46 PM EDT	Severe Thunderstorm Warning	PHI	44 min
Jun 4, 4:12 PM EDT	Mesoscale Discussion	SPC	93 min
Jun 4, 4:20 PM EDT	Severe Thunderstorm Warning	PHI	40 min
Jun 5, 3:35 PM EDT	Heat Advisory	PHI	4 days
Jun 8, 1:18 PM EDT	Areal Flood Advisory	PHI	3 hr
Jun 9, 3:49 PM EDT	Flash Flood Warning	PHI	3 hr
Jun 14, 1:40 PM EDT	Mesoscale Discussion	SPC	3 hr
Jun 14, 2:06 PM EDT	Severe Thunderstorm Watch	SPC	9 hr
Jun 14, 6:18 PM EDT	Mesoscale Discussion	SPC	117 min
Jun 14, 7:55 PM EDT	Severe Thunderstorm Warning	PHI	50 min
Jun 14, 8:34 PM EDT	Severe Thunderstorm Warning	PHI	41 min
Jun 14, 8:55 PM EDT	Severe Thunderstorm Warning	PHI	50 min
Jun 14, 9:12 PM EDT	Areal Flood Advisory	PHI	74 min
Jun 14, 9:17 PM EDT	Flash Flood Warning	PHI	3 hr
Jun 14, 9:29 PM EDT	Severe Thunderstorm Warning	PHI	46 min
Jun 21, 4:35 AM EDT	Heat Advisory	PHI	15 hr
Jun 21, 1:51 PM EDT	Mesoscale Discussion	SPC	114 min
Jun 21, 4:33 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 21, 6:15 PM EDT	Mesoscale Discussion	SPC	60 min
Jun 21, 7:12 PM EDT	Severe Thunderstorm Warning	PHI	48 min
Jun 27, 3:19 AM EDT	Heat Advisory	PHI	4 days
Jun 28, 3:13 PM EDT	Excessive Heat Warning	PHI	53 hr
Jun 28, 3:13 PM EDT	Heat Advisory	PHI	53 hr
Jun 30, 3:19 PM EDT	Flash Flood Watch	PHI	26 hr
Jul 1, 11:45 AM EDT	Mesoscale Discussion	SPC	2 hr
Jul 1, 12:46 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 1, 2:36 PM EDT	Mesoscale Discussion	SPC	84 min
Jul 1, 3:48 PM EDT	Areal Flood Advisory	PHI	112 min
Jul 1, 3:50 PM EDT	Severe Thunderstorm Warning	PHI	40 min
Jul 1, 4:16 PM EDT	Mesoscale Discussion	SPC	89 min
Jul 1, 4:27 PM EDT	Severe Thunderstorm Warning	PHI	48 min
Jul 1, 4:59 PM EDT	Severe Thunderstorm Warning	PHI	46 min
Jul 2, 11:16 AM EDT	Areal Flood Advisory	PHI	119 min
Jul 2, 3:13 PM EDT	Mesoscale Discussion	SPC	92 min
Jul 2, 4:54 PM EDT	Flash Flood Warning	PHI	5 hr
Jul 2, 7:41 PM EDT	Flash Flood Warning	PHI	3 hr
Jul 5, 3:21 AM EDT	Heat Advisory	PHI	65 hr
Jul 6, 12:33 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 6, 1:32 PM EDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 6, 4:23 PM EDT	Mesoscale Discussion	SPC	97 min
Jul 6, 5:11 PM EDT	Severe Thunderstorm Warning	PHI	49 min
Jul 6, 5:34 PM EDT	Severe Thunderstorm Warning	PHI	41 min
Jul 6, 6:13 PM EDT	Severe Thunderstorm Warning	PHI	31 min
Jul 6, 10:08 PM EDT	Special Weather Statement	PHI	37 min
Jul 6, 10:21 PM EDT	Severe Thunderstorm Warning	PHI	39 min
Jul 7, 3:32 PM EDT	Flash Flood Watch	PHI	42 hr
Jul 8, 1:44 PM EDT	Mesoscale Discussion	SPC	3 hr
Jul 8, 2:09 PM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 8, 4:36 PM EDT	Mesoscale Discussion	SPC	114 min
Jul 8, 5:21 PM EDT	Severe Thunderstorm Warning	PHI	39 min
Jul 9, 2:05 AM EDT	Areal Flood Advisory	PHI	8 hr
Jul 9, 4:44 AM EDT	Areal Flood Advisory	PHI	5 hr
Jul 9, 4:35 PM EDT	Mesoscale Discussion	SPC	115 min
Jul 9, 7:17 PM EDT	Severe Thunderstorm Warning	PHI	23 min
Jul 11, 3:45 PM EDT	Flash Flood Watch	PHI	36 hr
Jul 11, 6:18 PM EDT	Heat Advisory	PHI	50 hr
Jul 12, 1:32 PM EDT	Mesoscale Discussion	SPC	88 min
Jul 12, 1:59 PM EDT	Areal Flood Advisory	PHI	3 hr
Jul 12, 2:12 PM EDT	Flash Flood Warning Emergency	PHI	7 hr
Jul 12, 3:08 PM EDT	Severe Thunderstorm Warning	PHI	67 min
Jul 12, 3:34 PM EDT	Severe Thunderstorm Watch	SPC	5 hr
Jul 12, 4:16 PM EDT	Areal Flood Advisory	PHI	114 min
Jul 12, 5:08 PM EDT	Severe Thunderstorm Warning	PHI	67 min
Jul 12, 5:26 PM EDT	Areal Flood Advisory	PHI	2 hr
Jul 12, 6:01 PM EDT	Flash Flood Warning	PHI	102 min
Jul 12, 7:25 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 12, 8:37 PM EDT	Areal Flood Warning	PHI	9 hr
Jul 15, 2:33 PM EDT	Heat Advisory	PHI	52 hr
Jul 16, 3:17 PM EDT	Flash Flood Watch	PHI	35 hr
Jul 17, 12:00 PM EDT	Mesoscale Discussion	SPC	3 hr
Jul 17, 1:13 PM EDT	Severe Thunderstorm Watch	SPC	10 hr
Jul 17, 3:02 PM EDT	Mesoscale Discussion	SPC	88 min
Jul 17, 4:38 PM EDT	Mesoscale Discussion	SPC	97 min
Jul 17, 5:13 PM EDT	Areal Flood Advisory	PHI	4 hr
Jul 17, 6:51 PM EDT	Severe Thunderstorm Warning	PHI	39 min
Jul 17, 6:54 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 17, 7:12 PM EDT	Areal Flood Advisory	PHI	3 hr
Jul 17, 8:00 PM EDT	Severe Thunderstorm Warning	PHI	45 min
Jul 17, 9:15 PM EDT	Areal Flood Advisory	PHI	2 hr
Jul 17, 9:27 PM EDT	Severe Thunderstorm Warning	PHI	48 min
Jul 17, 9:36 PM EDT	Flash Flood Warning	PHI	2 hr
Jul 17, 9:48 PM EDT	Severe Thunderstorm Warning	PHI	42 min
Jul 17, 10:02 PM EDT	Mesoscale Discussion	SPC	58 min
Jul 21, 10:32 AM EDT	Mesoscale Discussion	SPC	58 min
Jul 21, 11:56 AM EDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 21, 2:39 PM EDT	Mesoscale Discussion	SPC	2 hr
Jul 21, 2:48 PM EDT	Severe Thunderstorm Warning	PHI	42 min
Jul 21, 3:16 PM EDT	Severe Thunderstorm Warning	PHI	44 min
Jul 21, 3:27 PM EDT	Severe Thunderstorm Warning	PHI	33 min
Jul 29, 2:23 PM EDT	Tornado Watch	SPC	8 hr
Jul 29, 4:26 PM EDT	Mesoscale Discussion	SPC	94 min
Jul 29, 6:45 PM EDT	Severe Thunderstorm Warning	PHI	45 min
Jul 29, 7:07 PM EDT	Tornado Warning	PHI	23 min
Jul 29, 7:09 PM EDT	Mesoscale Discussion	SPC	96 min
Jul 29, 7:12 PM EDT	Flash Flood Warning	PHI	4 hr
Aug 9, 3:43 PM EDT	Excessive Heat Watch	PHI	12 hr
Aug 9, 5:34 PM EDT	Special Weather Statement	PHI	26 min
Aug 9, 5:40 PM EDT	Areal Flood Advisory	PHI	82 min
Aug 9, 6:10 PM EDT	Special Weather Statement	PHI	35 min
Aug 10, 3:33 AM EDT	Excessive Heat Warning	PHI	4 days
Aug 10, 2:30 PM EDT	Mesoscale Discussion	SPC	3 hr
Aug 10, 5:09 PM EDT	Severe Thunderstorm Warning	PHI	51 min
Aug 10, 5:11 PM EDT	Special Weather Statement	PHI	34 min
Aug 10, 5:58 PM EDT	Special Weather Statement	PHI	32 min
Aug 10, 8:02 PM EDT	Severe Thunderstorm Warning	PHI	43 min
Aug 10, 8:36 PM EDT	Severe Thunderstorm Warning	PHI	39 min
Aug 10, 8:43 PM EDT	Areal Flood Advisory	PHI	2 hr
Aug 11, 3:02 PM EDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 11, 6:44 PM EDT	Mesoscale Discussion	SPC	91 min
Aug 11, 7:04 PM EDT	Areal Flood Advisory	PHI	2 hr
Aug 11, 7:11 PM EDT	Severe Thunderstorm Warning	PHI	49 min
Aug 12, 10:08 PM EDT	Mesoscale Discussion	SPC	67 min
Aug 19, 12:44 AM EDT	Mesoscale Discussion	SPC	61 min
Aug 19, 12:47 AM EDT	Tornado Warning	PHI	28 min
Aug 19, 1:14 AM EDT	Special Weather Statement	PHI	91 min
Aug 19, 1:30 AM EDT	Flash Flood Warning	PHI	4 hr
Aug 19, 2:13 AM EDT	Flash Flood Warning	PHI	4 hr
Aug 19, 6:09 AM EDT	Areal Flood Warning	PHI	3 hr
Aug 19, 8:50 AM EDT	Areal Flood Warning	PHI	3 hr
Aug 21, 3:27 AM EDT	Flood Watch	PHI	53 hr
Aug 25, 2:13 PM EDT	Heat Advisory	PHI	53 hr
Aug 26, 3:30 PM EDT	Flash Flood Watch	PHI	48 hr
Aug 26, 6:56 PM EDT	Special Weather Statement	PHI	34 min
Aug 27, 1:33 PM EDT	Areal Flood Advisory	PHI	83 min
Aug 28, 3:06 AM EDT	Areal Flood Advisory	PHI	2 hr
Aug 28, 11:57 AM EDT	Flash Flood Warning	PHI	3 hr
Aug 30, 5:00 AM EDT	Flash Flood Watch	PHI	71 hr
Sep 1, 6:49 AM EDT	Flash Flood Warning	PHI	86 min
Sep 1, 12:40 PM EDT	Tornado Watch	SPC	9 hr
Sep 1, 3:09 PM EDT	Mesoscale Discussion	SPC	3 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	43 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	41 hr
Sep 1, 3:55 PM EDT	River Flood Warning	PHI	39 hr
Sep 1, 4:28 PM EDT	Mesoscale Discussion	SPC	2 hr
Sep 1, 5:13 PM EDT	Severe Thunderstorm Warning	PHI	47 min
Sep 1, 5:15 PM EDT	Tornado Warning	PHI	30 min
Sep 1, 5:26 PM EDT	Flash Flood Warning	PHI	9 hr
Sep 1, 5:34 PM EDT	Tornado Warning	PHI	26 min
Sep 1, 6:22 PM EDT	Tornado Warning Tornado observed	PHI	23 min
Sep 1, 6:34 PM EDT	Mesoscale Discussion	SPC	56 min
Sep 1, 6:42 PM EDT	Tornado Warning	PHI	33 min
Sep 1, 10:24 PM EDT	Flash Flood Warning	PHI	4 hr
Sep 2, 2:23 AM EDT	Areal Flood Warning	PHI	9 hr
Sep 2, 2:29 AM EDT	Areal Flood Warning	PHI	5 hr
Sep 2, 6:05 AM EDT	Coastal Flood Warning	PHI	6 hr
Sep 2, 6:44 PM EDT	Coastal Flood Advisory	PHI	7 hr
Sep 7, 2:33 PM EDT	Flash Flood Watch	PHI	37 hr
Sep 9, 12:08 AM EDT	Special Weather Statement	PHI	37 min
Sep 22, 3:24 AM EDT	Flash Flood Watch	PHI	41 hr
Sep 23, 9:12 AM EDT	Coastal Flood Advisory	PHI	10 hr
Sep 23, 10:30 AM EDT	Mesoscale Discussion	SPC	2 hr
Sep 23, 11:33 AM EDT	Areal Flood Advisory	PHI	3 hr
Sep 23, 12:12 PM EDT	Severe Thunderstorm Warning	PHI	48 min
Sep 23, 12:28 PM EDT	Flash Flood Warning	PHI	4 hr
Sep 23, 12:54 PM EDT	Special Weather Statement	PHI	51 min
Sep 23, 12:56 PM EDT	Areal Flood Advisory	PHI	3 hr
Sep 23, 1:13 PM EDT	Severe Thunderstorm Warning	PHI	47 min
Sep 23, 1:29 PM EDT	Mesoscale Discussion	SPC	61 min
Sep 23, 1:42 PM EDT	Flash Flood Warning	PHI	4 hr
Sep 23, 4:26 PM EDT	Areal Flood Warning	PHI	80 min
Oct 4, 4:44 PM EDT	Mesoscale Discussion	SPC	2 hr
Oct 5, 2:10 AM EDT	Areal Flood Advisory	PHI	4 hr
Oct 5, 2:27 AM EDT	Flash Flood Warning	PHI	3 hr
Oct 8, 5:24 AM EDT	Coastal Flood Advisory	PHI	4 days
Oct 14, 3:16 AM EDT	Dense Fog Advisory	PHI	3 hr
Oct 16, 1:50 PM EDT	Mesoscale Discussion	SPC	115 min
Oct 16, 4:18 PM EDT	Special Weather Statement	PHI	57 min
Oct 24, 3:09 PM EDT	Flash Flood Watch	PHI	48 hr
Oct 25, 6:41 PM EDT	Mesoscale Discussion	SPC	2 hr
Oct 25, 7:34 PM EDT	Severe Thunderstorm Warning	PHI	26 min
Oct 27, 5:08 PM EDT	Coastal Flood Advisory	PHI	34 hr
Oct 28, 3:22 AM EDT	Coastal Flood Watch	PHI	15 hr
Oct 28, 6:20 PM EDT	Coastal Flood Warning	PHI	55 hr
Oct 29, 7:38 PM EDT	Areal Flood Advisory	PHI	3 hr
Oct 29, 8:51 PM EDT	Areal Flood Advisory	PHI	3 hr
Oct 30, 4:41 PM EDT	Coastal Flood Advisory	PHI	31 hr
Nov 2, 3:30 AM EDT	Frost Advisory	PHI	30 hr
Nov 3, 1:52 PM EDT	Frost Advisory	PHI	19 hr
Nov 13, 2:55 AM EST	Wind Advisory	PHI	14 hr
Dec 10, 3:58 AM EST	Wind Advisory	PHI	45 hr
Dec 11, 7:29 PM EST	Mesoscale Discussion	SPC	3 hr
Dec 11, 9:01 PM EST	Severe Thunderstorm Warning	PHI	48 min
Dec 30, 9:33 PM EST	Dense Fog Advisory	PHI	11 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	42
Tornado Warning	6
Severe Thunderstorm Watch	14
Tornado Watch	2
Mesoscale Discussion	48
Special Weather Statement	15
Flooding
Areal Flood Warning	7
Flash Flood Warning	18
River Flood Warning	3
Flash Flood Watch	10
Flood Watch	1
Areal Flood Advisory	29
Winter
Winter Storm Warning	3
Winter Storm Watch	3
Winter Weather Advisory	6
Heat
Excessive Heat Warning	2
Excessive Heat Watch	1
Heat Advisory	8
Cold
Frost Advisory	3
Wind and dust
High Wind Warning	1
High Wind Watch	1
Wind Advisory	6
Fire
Red Flag Warning	1
Fire Weather Watch	1
Fog and smoke
Dense Fog Advisory	3
Coast and beach
Coastal Flood Warning	2
Coastal Flood Watch	1
Coastal Flood Advisory	6

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2020 2022

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.