Weather alerts in Shelby County, Alabama, 2020

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

Shelby County and its neighbors

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

Alerts: 178
Warnings: 47
Watches: 22
Advisories: 48
Busiest month: February39 alerts
Busiest day: February 6, 202012 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 2 tornado warnings covering Shelby County in 2020 had a tornado report inside them; 0 of 3 tornado reports fell inside a warning.

Shelby County, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	2	0	100%	3	0%
Severe thunderstorm warnings	18	16	11%	36	50%	18 min
Flash flood warnings	8	7	13%	14	100%	118 min

Each office's whole area, 2020

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Birmingham, AL: tornado warnings	40	16	60%	62	68%	17 min
NWS Birmingham, AL: severe thunderstorm warnings	206	150	27%	663	66%	25 min
NWS Birmingham, AL: flash flood warnings	36	27	25%	123	82%	117 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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Jan 2, 1:48 PM CST	Areal Flood Advisory	BMX	3 hr
Jan 3, 4:59 AM CST	Dense Fog Advisory	BMX	4 hr
Jan 9, 1:49 PM CST	Wind Advisory	BMX	55 hr
Jan 11, 7:57 AM CST	Tornado Watch	SPC	9 hr
Jan 11, 11:50 AM CST	Mesoscale Discussion	SPC	85 min
Jan 11, 12:01 PM CST	Severe Thunderstorm Warning	BMX	59 min
Jan 11, 12:52 PM CST	Severe Thunderstorm Warning	BMX	68 min
Jan 11, 1:15 PM CST	Mesoscale Discussion	SPC	90 min
Jan 11, 1:19 PM CST	Areal Flood Advisory	BMX	116 min
Jan 11, 2:02 PM CST	Severe Thunderstorm Warning	BMX	14 min
Jan 14, 3:03 AM CST	Flash Flood Watch	BMX	18 hr
Jan 15, 3:18 AM CST	Dense Fog Advisory	BMX	8 hr
Jan 24, 5:05 AM CST	Dense Fog Advisory	BMX	4 hr
Jan 27, 5:07 AM CST	Dense Fog Advisory	BMX	4 hr
Jan 28, 12:20 AM CST	Dense Fog Advisory	BMX	9 hr
Feb 4, 2:08 PM CST	Flash Flood Watch	BMX	48 hr
Feb 5, 2:23 PM CST	Special Weather Statement	BMX	37 min
Feb 5, 2:47 PM CST	Special Weather Statement	BMX	43 min
Feb 5, 3:47 PM CST	Mesoscale Discussion	SPC	118 min
Feb 5, 4:25 PM CST	Tornado Watch	SPC	5 hr
Feb 5, 11:15 PM CST	Mesoscale Discussion	SPC	2 hr
Feb 5, 11:48 PM CST	Tornado Watch	SPC	8 hr
Feb 6, 1:33 AM CST	Special Weather Statement	BMX	57 min
Feb 6, 1:59 AM CST	Tornado Warning	BMX	20 min
Feb 6, 2:23 AM CST	Tornado Warning	BMX	52 min
Feb 6, 3:12 AM CST	Severe Thunderstorm Warning	BMX	51 min
Feb 6, 3:35 AM CST	Flash Flood Warning	BMX	3 hr
Feb 6, 4:12 AM CST	Special Weather Statement	BMX	48 min
Feb 6, 6:32 AM CST	Flash Flood Warning	BMX	3 hr
Feb 6, 6:39 AM CST	River Flood Warning	BMX	37 hr
Feb 6, 6:52 AM CST	Areal Flood Warning	BMX	6 hr
Feb 6, 9:28 AM CST	Areal Flood Warning	BMX	3 hr
Feb 7, 1:28 PM CST	River Flood Warning	BMX	11 days
Feb 8, 9:26 PM CST	Dense Fog Advisory	BMX	12 hr
Feb 9, 3:52 AM CST	Flood Watch	BMX	24 hr
Feb 9, 11:14 AM CST	River Flood Warning	BMX	57 hr
Feb 10, 3:40 AM CST	Flash Flood Watch	BMX	30 hr
Feb 10, 11:33 AM CST	Areal Flood Advisory	BMX	6 hr
Feb 10, 12:32 PM CST	Flash Flood Warning	BMX	6 hr
Feb 10, 6:13 PM CST	Areal Flood Warning	BMX	6 hr
Feb 11, 12:19 AM CST	Areal Flood Warning	BMX	6 hr
Feb 11, 7:37 AM CST	Areal Flood Advisory	BMX	3 hr
Feb 11, 3:43 PM CST	Flash Flood Watch	BMX	38 hr
Feb 12, 8:26 AM CST	River Flood Warning	BMX	12 hr
Feb 12, 4:34 PM CST	Severe Thunderstorm Watch	SPC	5 hr
Feb 13, 2:27 AM CST	Special Weather Statement	BMX	33 min
Feb 13, 2:45 AM CST	Special Weather Statement	BMX	30 min
Feb 17, 2:36 AM CST	Dense Fog Advisory	BMX	6 hr
Feb 18, 2:57 AM CST	Flash Flood Watch	BMX	22 hr
Feb 18, 4:01 PM CST	Mesoscale Discussion	SPC	89 min
Feb 18, 4:45 PM CST	Areal Flood Advisory	BMX	6 hr
Feb 18, 5:43 PM CST	Flash Flood Warning	BMX	3 hr
Feb 18, 6:37 PM CST	Areal Flood Advisory	BMX	3 hr
Feb 19, 6:03 AM CST	River Flood Warning	BMX	6 days
Mar 3, 2:35 PM CST	Flash Flood Watch	BMX	45 hr
Mar 3, 10:19 PM CST	Dense Fog Advisory	BMX	6 hr
Mar 5, 5:37 AM CST	Areal Flood Warning	BMX	6 hr
Mar 5, 8:31 AM CST	River Flood Warning	BMX	35 hr
Mar 5, 9:34 PM CST	Dense Fog Advisory	BMX	8 hr
Mar 6, 5:13 AM CST	Wind Advisory	BMX	13 hr
Mar 31, 7:59 AM CDT	Special Weather Statement	BMX	31 min
Mar 31, 8:05 AM CDT	Severe Thunderstorm Warning	BMX	40 min
Mar 31, 8:18 AM CDT	Severe Thunderstorm Warning	BMX	42 min
Mar 31, 8:38 AM CDT	Severe Thunderstorm Warning	BMX	52 min
Apr 8, 5:50 AM CDT	Dense Fog Advisory	BMX	3 hr
Apr 8, 12:13 PM CDT	Mesoscale Discussion	SPC	2 hr
Apr 8, 2:40 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
Apr 11, 2:04 PM CDT	Wind Advisory	BMX	42 hr
Apr 12, 1:45 PM CDT	Mesoscale Discussion	SPC	90 min
Apr 12, 3:20 PM CDT	Tornado Watch	SPC	8 hr
Apr 12, 4:38 PM CDT	Tornado Watch PDS	SPC	7 hr
Apr 12, 7:36 PM CDT	Mesoscale Discussion	SPC	84 min
Apr 12, 8:50 PM CDT	Mesoscale Discussion	SPC	55 min
Apr 12, 9:19 PM CDT	Severe Thunderstorm Warning	BMX	71 min
Apr 12, 10:28 PM CDT	Mesoscale Discussion	SPC	92 min
Apr 12, 10:59 PM CDT	Severe Thunderstorm Warning	BMX	43 min
Apr 13, 1:29 AM CDT	High Wind Warning	BMX	3 hr
Apr 13, 1:29 AM CDT	Wind Advisory	BMX	7 hr
Apr 13, 2:25 AM CDT	River Flood Warning	BMX	18 hr
Apr 14, 1:48 AM CDT	Frost Advisory	BMX	30 hr
Apr 18, 3:50 AM CDT	Flash Flood Watch	BMX	48 hr
Apr 19, 6:14 AM CDT	Special Weather Statement	BMX	46 min
Apr 19, 6:24 AM CDT	Severe Thunderstorm Warning	BMX	36 min
Apr 19, 7:52 AM CDT	Severe Thunderstorm Warning	BMX	24 min
Apr 19, 8:00 AM CDT	Flash Flood Warning	BMX	3 hr
Apr 19, 8:52 AM CDT	River Flood Warning	BMX	29 hr
Apr 19, 10:59 AM CDT	Flash Flood Warning Considerable damage threat	BMX	3 hr
Apr 19, 11:42 AM CDT	Areal Flood Advisory	BMX	3 hr
Apr 19, 1:57 PM CDT	Areal Flood Warning	BMX	6 hr
Apr 19, 2:53 PM CDT	Areal Flood Advisory	BMX	3 hr
Apr 22, 10:23 PM CDT	Wind Advisory	BMX	14 hr
Apr 23, 5:12 AM CDT	Areal Flood Advisory	BMX	3 hr
Apr 23, 5:24 AM CDT	Special Weather Statement	BMX	51 min
Apr 23, 4:06 PM CDT	Severe Thunderstorm Watch	SPC	113 min
Apr 25, 4:40 PM CDT	Wind Advisory	BMX	5 hr
Apr 26, 2:42 AM CDT	Wind Advisory	BMX	16 hr
May 6, 2:39 AM CDT	Wind Advisory	BMX	18 hr
May 7, 3:12 PM CDT	Wind Advisory	BMX	26 hr
May 22, 4:43 PM CDT	Special Weather Statement	BMX	47 min
May 22, 4:53 PM CDT	Severe Thunderstorm Warning	BMX	37 min
May 22, 7:11 PM CDT	Special Weather Statement	BMX	49 min
May 22, 7:36 PM CDT	Areal Flood Advisory	BMX	114 min
May 23, 3:05 AM CDT	Dense Fog Advisory	BMX	6 hr
May 23, 4:23 PM CDT	Special Weather Statement	BMX	37 min
May 23, 4:57 PM CDT	Special Weather Statement	BMX	48 min
May 23, 5:00 PM CDT	Areal Flood Advisory	BMX	2 hr
May 23, 5:53 PM CDT	Mesoscale Discussion	SPC	3 hr
May 27, 12:16 PM CDT	Mesoscale Discussion	SPC	89 min
May 27, 2:38 PM CDT	Special Weather Statement	BMX	67 min
May 27, 2:59 PM CDT	Areal Flood Advisory	BMX	3 hr
May 27, 3:53 PM CDT	Special Weather Statement	BMX	37 min
Jun 5, 9:53 AM CDT	Mesoscale Discussion	SPC	2 hr
Jun 5, 1:21 PM CDT	Special Weather Statement	BMX	24 min
Jun 5, 1:38 PM CDT	Special Weather Statement	BMX	52 min
Jun 9, 2:23 PM CDT	Areal Flood Advisory	BMX	98 min
Jun 9, 2:47 PM CDT	Special Weather Statement	BMX	28 min
Jun 9, 3:14 PM CDT	Areal Flood Advisory	BMX	106 min
Jun 22, 1:19 PM CDT	Severe Thunderstorm Warning	BMX	23 min
Jun 22, 2:00 PM CDT	Special Weather Statement	BMX	45 min
Jun 23, 4:17 PM CDT	Special Weather Statement	BMX	43 min
Jun 23, 4:51 PM CDT	Special Weather Statement	BMX	54 min
Jun 23, 6:25 PM CDT	Severe Thunderstorm Warning	BMX	34 min
Jun 25, 6:45 PM CDT	Mesoscale Discussion	SPC	90 min
Jun 25, 8:58 PM CDT	Special Weather Statement	BMX	47 min
Jun 25, 9:20 PM CDT	Severe Thunderstorm Warning	BMX	42 min
Jun 29, 3:45 PM CDT	Special Weather Statement	BMX	30 min
Jun 29, 5:55 PM CDT	Special Weather Statement	BMX	50 min
Jun 29, 6:10 PM CDT	Severe Thunderstorm Warning	BMX	31 min
Jun 29, 6:43 PM CDT	Areal Flood Advisory	BMX	3 hr
Jun 29, 6:45 PM CDT	Special Weather Statement	BMX	45 min
Jun 29, 7:14 PM CDT	Flash Flood Warning	BMX	93 min
Jun 30, 9:40 PM CDT	Special Weather Statement	BMX	50 min
Jul 1, 8:38 PM CDT	Special Weather Statement	BMX	67 min
Jul 8, 6:54 AM CDT	Areal Flood Advisory	BMX	3 hr
Jul 12, 10:46 AM CDT	Mesoscale Discussion	SPC	119 min
Jul 12, 12:09 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 12, 1:25 PM CDT	Severe Thunderstorm Warning	BMX	65 min
Jul 12, 1:40 PM CDT	Mesoscale Discussion	SPC	95 min
Jul 13, 3:10 AM CDT	Dense Fog Advisory	BMX	6 hr
Jul 23, 7:12 PM CDT	Special Weather Statement	BMX	33 min
Jul 23, 7:36 PM CDT	Special Weather Statement	BMX	39 min
Jul 25, 1:45 PM CDT	Special Weather Statement	BMX	30 min
Jul 25, 2:21 PM CDT	Special Weather Statement	BMX	24 min
Jul 25, 7:38 PM CDT	Special Weather Statement	BMX	37 min
Jul 31, 3:13 PM CDT	Severe Thunderstorm Warning	BMX	42 min
Jul 31, 5:23 PM CDT	Mesoscale Discussion	SPC	2 hr
Aug 10, 5:23 PM CDT	Special Weather Statement	BMX	37 min
Aug 11, 5:59 PM CDT	Special Weather Statement	BMX	31 min
Aug 19, 6:59 PM CDT	Special Weather Statement	BMX	31 min
Aug 21, 7:24 PM CDT	Special Weather Statement	BMX	36 min
Aug 28, 10:21 AM CDT	Flash Flood Watch	BMX	49 min
Aug 28, 11:10 AM CDT	Flash Flood Watch	BMX	7 hr
Aug 30, 1:39 PM CDT	Mesoscale Discussion	SPC	3 hr
Aug 30, 3:43 PM CDT	Areal Flood Advisory	BMX	3 hr
Aug 31, 8:10 PM CDT	Areal Flood Advisory	BMX	2 hr
Aug 31, 8:33 PM CDT	Special Weather Statement	BMX	27 min
Aug 31, 9:17 PM CDT	Areal Flood Advisory	BMX	118 min
Sep 14, 4:27 AM CDT	Flash Flood Watch	BMX	3 days
Sep 15, 8:42 PM CDT	River Flood Warning	BMX	13 hr
Sep 24, 3:54 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 28, 2:56 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 28, 4:57 PM CDT	Special Weather Statement	BMX	33 min
Oct 27, 4:11 AM CDT	Tropical Storm Watch	BMX	30 hr
Oct 27, 4:30 PM CDT	Flash Flood Watch	BMX	37 hr
Oct 28, 10:06 AM CDT	Tropical Storm Warning	BMX	21 hr
Oct 29, 12:51 AM CDT	Flash Flood Warning	BMX	3 hr
Nov 1, 2:14 AM CST	Freeze Warning	BMX	30 hr
Nov 2, 1:22 PM CST	Frost Advisory	BMX	18 hr
Nov 12, 10:15 PM CST	Dense Fog Advisory	BMX	10 hr
Nov 17, 8:51 AM CST	Freeze Warning	BMX	23 hr
Nov 25, 11:17 AM CST	Special Weather Statement	BMX	43 min
Nov 29, 11:11 PM CST	Wind Advisory	BMX	7 hr
Dec 6, 3:23 AM CST	Freezing Fog Advisory	BMX	5 hr
Dec 12, 6:57 PM CST	Dense Fog Advisory	BMX	15 hr
Dec 14, 1:11 AM CST	Special Weather Statement	BMX	49 min
Dec 14, 1:27 AM CST	Mesoscale Discussion	SPC	93 min
Dec 23, 2:43 PM CST	Wind Advisory	BMX	27 hr
Dec 29, 3:57 AM CST	Dense Fog Advisory	BMX	5 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	18
Tornado Warning	2
Severe Thunderstorm Watch	4
Tornado Watch	5
Mesoscale Discussion	21
Special Weather Statement	40
Flooding
Areal Flood Warning	6
Flash Flood Warning	8
River Flood Warning	9
Flash Flood Watch	11
Flood Watch	1
Areal Flood Advisory	19
Cold
Freeze Warning	2
Frost Advisory	2
Wind and dust
High Wind Warning	1
Wind Advisory	11
Fog and smoke
Dense Fog Advisory	15
Freezing Fog Advisory	1
Tropical
Tropical Storm Warning	1
Tropical Storm Watch	1

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2019 2021

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.