Alert archive / Missouri / Saint Louis County

Weather alerts in Saint Louis County, Missouri, 2015

154 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Saint Louis County and its neighbors

Each county as a circle sized by its count in 2015. Tap one for its archive.

Alerts: 154
Warnings: 61
Watches: 25
Advisories: 34
Busiest month: June37 alerts
Busiest day: April 7, 20158 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 2 tornado warnings covering Saint Louis County in 2015 had a tornado report inside them.

Saint Louis County, 2015

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	2	1	50%	0
Severe thunderstorm warnings	21	13	38%	23	70%	24 min
Flash flood warnings	6	4	33%	4	100%	169 min

Each office's whole area, 2015

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS St. Louis, MO: tornado warnings	45	5	89%	16	50%	11 min
NWS St. Louis, MO: severe thunderstorm warnings	214	98	54%	378	74%	23 min
NWS St. Louis, MO: flash flood warnings	96	41	57%	126	83%	176 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 6, 4:16 AM CST	Wind Chill Advisory	LSX	53 hr
Jan 10, 3:10 PM CST	Winter Weather Advisory	LSX	42 hr
Feb 15, 2:50 AM CST	Winter Storm Warning	LSX	37 hr
Feb 19, 3:58 PM CST	Winter Weather Advisory	LSX	42 hr
Feb 20, 3:22 PM CST	Winter Storm Warning	LSX	21 hr
Feb 20, 6:37 PM CST	Mesoscale Discussion	SPC	6 hr
Feb 22, 3:36 AM CST	Wind Chill Advisory	LSX	29 hr
Feb 27, 4:12 PM CST	Winter Weather Advisory	LSX	47 hr
Feb 28, 4:15 AM CST	Winter Storm Warning	LSX	35 hr
Mar 2, 3:58 PM CST	Winter Weather Advisory	LSX	16 hr
Mar 10, 9:40 PM CDT	Dense Fog Advisory	LSX	13 hr
Mar 11, 3:50 PM CDT	Flood Watch	LSX	60 hr
Apr 2, 2:46 PM CDT	Mesoscale Discussion	SPC	89 min
Apr 2, 3:48 PM CDT	Severe Thunderstorm Warning	LSX	27 min
Apr 2, 4:14 PM CDT	Severe Thunderstorm Warning	LSX	31 min
Apr 2, 10:23 PM CDT	Severe Thunderstorm Warning	LSX	52 min
Apr 7, 7:56 AM CDT	Severe Thunderstorm Warning	LSX	49 min
Apr 7, 8:17 AM CDT	Mesoscale Discussion	SPC	88 min
Apr 7, 8:34 AM CDT	Severe Thunderstorm Watch	SPC	7 hr
Apr 7, 8:42 AM CDT	Severe Thunderstorm Warning	LSX	48 min
Apr 7, 9:26 AM CDT	Severe Thunderstorm Warning	LSX	49 min
Apr 7, 9:42 AM CDT	Flash Flood Warning	LSX	8 hr
Apr 7, 10:03 AM CDT	Severe Thunderstorm Warning	LSX	42 min
Apr 7, 10:43 AM CDT	Areal Flood Advisory	LSX	4 hr
Apr 8, 12:01 PM CDT	Mesoscale Discussion	SPC	59 min
Apr 8, 12:50 PM CDT	Mesoscale Discussion	SPC	85 min
Apr 8, 1:05 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Apr 8, 2:43 PM CDT	Mesoscale Discussion	SPC	92 min
Apr 8, 3:24 PM CDT	Flash Flood Watch	LSX	31 hr
Apr 9, 6:10 AM CDT	Areal Flood Advisory	LSX	4 hr
Apr 9, 3:45 PM CDT	Mesoscale Discussion	SPC	60 min
Apr 9, 4:40 PM CDT	Tornado Watch	SPC	6 hr
Apr 9, 6:12 PM CDT	River Flood Warning	LSX	3 days
Apr 9, 6:55 PM CDT	Severe Thunderstorm Warning	LSX	35 min
Apr 9, 7:27 PM CDT	Severe Thunderstorm Warning	LSX	37 min
Apr 9, 8:56 PM CDT	River Flood Warning	LSX	56 hr
Apr 22, 3:27 PM CDT	Frost Advisory	LSX	17 hr
Apr 25, 12:22 PM CDT	Mesoscale Discussion	SPC	2 hr
Apr 25, 12:55 PM CDT	Tornado Watch	SPC	7 hr
Apr 25, 3:25 PM CDT	Mesoscale Discussion	SPC	2 hr
May 10, 3:52 PM CDT	Mesoscale Discussion	SPC	68 min
May 10, 4:02 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
May 10, 5:19 PM CDT	Severe Thunderstorm Warning	LSX	41 min
May 15, 2:13 PM CDT	Mesoscale Discussion	SPC	2 hr
May 19, 11:36 AM CDT	River Flood Warning	LSX	4 days
May 24, 4:14 PM CDT	Tornado Watch	SPC	8 hr
May 24, 6:04 PM CDT	Mesoscale Discussion	SPC	116 min
May 24, 8:41 PM CDT	Mesoscale Discussion	SPC	64 min
May 26, 9:48 PM CDT	River Flood Warning	LSX	8 days
May 27, 3:53 AM CDT	Mesoscale Discussion	SPC	2 hr
May 29, 10:17 AM CDT	River Flood Warning	LSX	4 days
May 29, 8:55 PM CDT	Flash Flood Watch	LSX	22 hr
May 30, 9:00 PM CDT	River Flood Warning	LSX	4 days
Jun 5, 11:40 AM CDT	River Flood Warning	LSX	32 days
Jun 7, 10:36 AM CDT	River Flood Warning	LSX	49 days
Jun 9, 10:49 PM CDT	River Flood Warning	LSX	44 hr
Jun 12, 4:15 PM CDT	Severe Thunderstorm Warning	LSX	45 min
Jun 12, 4:48 PM CDT	Severe Thunderstorm Warning	LSX	42 min
Jun 12, 5:25 PM CDT	Severe Thunderstorm Warning	LSX	28 min
Jun 13, 3:51 PM CDT	Mesoscale Discussion	SPC	84 min
Jun 14, 11:43 AM CDT	River Flood Warning	LSX	41 days
Jun 14, 6:59 PM CDT	Areal Flood Advisory	LSX	4 hr
Jun 16, 3:42 AM CDT	Flash Flood Watch	LSX	4 days
Jun 16, 3:12 PM CDT	Areal Flood Advisory	LSX	6 hr
Jun 16, 8:18 PM CDT	River Flood Warning	LSX	8 days
Jun 16, 9:07 PM CDT	Areal Flood Advisory	LSX	6 hr
Jun 17, 2:57 AM CDT	Areal Flood Advisory	LSX	7 hr
Jun 17, 10:09 AM CDT	Areal Flood Advisory	LSX	6 hr
Jun 17, 2:47 PM CDT	River Flood Warning	LSX	8 days
Jun 19, 7:36 AM CDT	Areal Flood Advisory	LSX	6 hr
Jun 19, 10:34 AM CDT	Flash Flood Warning	LSX	6 hr
Jun 21, 3:46 AM CDT	Heat Advisory	LSX	39 hr
Jun 21, 9:42 AM CDT	Mesoscale Discussion	SPC	2 hr
Jun 21, 9:57 AM CDT	Severe Thunderstorm Warning	LSX	31 min
Jun 25, 4:06 AM CDT	Flash Flood Watch	LSX	39 hr
Jun 25, 3:55 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 25, 4:53 PM CDT	Severe Thunderstorm Watch	SPC	9 hr
Jun 25, 5:51 PM CDT	Severe Thunderstorm Warning	LSX	54 min
Jun 25, 7:27 PM CDT	Mesoscale Discussion	SPC	93 min
Jun 25, 9:03 PM CDT	Severe Thunderstorm Warning	LSX	42 min
Jun 26, 6:48 AM CDT	Areal Flood Advisory	LSX	6 hr
Jun 26, 10:42 PM CDT	River Flood Warning	LSX	8 days
Jun 28, 1:36 PM CDT	Mesoscale Discussion	SPC	114 min
Jun 28, 3:03 PM CDT	Tornado Watch	SPC	8 hr
Jun 28, 5:56 PM CDT	Mesoscale Discussion	SPC	94 min
Jun 28, 8:02 PM CDT	Tornado Warning	LSX	28 min
Jun 28, 8:26 PM CDT	Tornado Warning	LSX	37 min
Jun 28, 8:48 PM CDT	Severe Thunderstorm Warning	LSX	42 min
Jun 28, 9:17 PM CDT	Areal Flood Advisory	LSX	3 hr
Jun 28, 9:50 PM CDT	Flash Flood Warning	LSX	6 hr
Jul 1, 7:35 PM CDT	Areal Flood Advisory	LSX	4 hr
Jul 1, 7:38 PM CDT	Severe Thunderstorm Warning	LSX	37 min
Jul 1, 8:16 PM CDT	Mesoscale Discussion	SPC	119 min
Jul 6, 3:55 AM CDT	Flash Flood Watch	LSX	68 hr
Jul 8, 10:15 AM CDT	River Flood Warning	LSX	8 days
Jul 9, 3:35 AM CDT	Flash Flood Watch	LSX	27 hr
Jul 10, 2:52 PM CDT	River Flood Warning	LSX	64 hr
Jul 11, 3:30 PM CDT	Heat Advisory	LSX	3 days
Jul 11, 8:00 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 11, 9:57 PM CDT	Mesoscale Discussion	SPC	93 min
Jul 13, 4:33 PM CDT	Mesoscale Discussion	SPC	57 min
Jul 13, 6:20 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
Jul 16, 3:46 PM CDT	Heat Advisory	LSX	3 days
Jul 17, 10:50 AM CDT	River Flood Warning	LSX	11 days
Jul 18, 11:19 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 19, 1:46 AM CDT	Mesoscale Discussion	SPC	89 min
Jul 19, 4:45 AM CDT	Mesoscale Discussion	SPC	90 min
Jul 19, 4:03 PM CDT	Flash Flood Watch	LSX	20 hr
Jul 20, 9:43 AM CDT	Severe Thunderstorm Warning	LSX	47 min
Jul 26, 2:06 AM CDT	Mesoscale Discussion	SPC	2 hr
Jul 26, 4:23 AM CDT	Special Weather Statement	LSX	52 min
Jul 26, 3:55 PM CDT	Heat Advisory	LSX	53 hr
Jul 27, 3:40 PM CDT	Excessive Heat Warning	LSX	48 hr
Jul 27, 5:53 PM CDT	Severe Thunderstorm Warning	LSX	20 min
Aug 4, 2:44 PM CDT	Flash Flood Watch	LSX	25 hr
Aug 5, 8:19 PM CDT	Areal Flood Advisory	LSX	6 hr
Aug 5, 10:36 PM CDT	Flash Flood Warning	LSX	8 hr
Aug 9, 3:55 PM CDT	Mesoscale Discussion	SPC	2 hr
Aug 9, 8:35 PM CDT	Severe Thunderstorm Warning	LSX	40 min
Aug 18, 12:49 PM CDT	Mesoscale Discussion	SPC	116 min
Aug 18, 1:15 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Aug 18, 3:16 PM CDT	Mesoscale Discussion	SPC	119 min
Oct 16, 2:36 AM CDT	Frost Advisory	LSX	29 hr
Oct 17, 2:52 AM CDT	Frost Advisory	LSX	29 hr
Nov 1, 3:48 AM CST	Dense Fog Advisory	LSX	4 hr
Nov 1, 11:07 PM CST	Dense Fog Advisory	LSX	11 hr
Nov 2, 8:43 PM CST	Dense Fog Advisory	LSX	13 hr
Nov 3, 7:16 PM CST	Dense Fog Advisory	LSX	15 hr
Nov 10, 6:56 PM CST	Wind Advisory	LSX	35 hr
Nov 16, 4:13 AM CST	Flash Flood Watch	LSX	48 hr
Nov 25, 3:24 AM CST	Flood Watch	LSX	3 days
Nov 28, 7:38 PM CST	River Flood Warning	LSX	5 days
Dec 4, 7:12 PM CST	Dense Fog Advisory	LSX	15 hr
Dec 11, 3:55 AM CST	Dense Fog Advisory	LSX	7 hr
Dec 15, 11:23 AM CST	River Flood Warning	LSX	6 days
Dec 15, 12:50 PM CST	River Flood Warning	LSX	9 days
Dec 15, 8:10 PM CST	River Flood Warning	LSX	30 days
Dec 23, 6:13 AM CST	Mesoscale Discussion	SPC	2 hr
Dec 23, 12:42 PM CST	Mesoscale Discussion	SPC	2 hr
Dec 23, 1:55 PM CST	Tornado Watch	SPC	4 hr
Dec 23, 3:24 PM CST	Mesoscale Discussion	SPC	96 min
Dec 24, 9:28 PM CST	River Flood Warning	LSX	9 days
Dec 24, 9:28 PM CST	River Flood Warning	LSX	11 days
Dec 24, 10:11 PM CST	River Flood Warning	LSX	13 days
Dec 25, 2:17 AM CST	Flash Flood Watch	LSX	4 days
Dec 26, 1:40 PM CST	River Flood Warning	LSX	8 days
Dec 26, 2:41 PM CST	Flash Flood Warning	LSX	13 hr
Dec 26, 8:29 PM CST	Special Weather Statement	LSX	46 min
Dec 27, 3:17 AM CST	Areal Flood Warning	LSX	12 hr
Dec 27, 3:05 PM CST	Areal Flood Warning	LSX	24 hr
Dec 27, 3:55 PM CST	Wind Advisory	LSX	23 hr
Dec 28, 4:28 AM CST	Flash Flood Warning	LSX	8 hr
Dec 28, 12:37 PM CST	Areal Flood Warning	LSX	24 hr
Dec 29, 12:14 PM CST	Areal Flood Warning	LSX	24 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	21
Tornado Warning	2
Severe Thunderstorm Watch	8
Tornado Watch	5
Mesoscale Discussion	32
Special Weather Statement	2
Flooding
Areal Flood Warning	4
Flash Flood Warning	6
River Flood Warning	24
Flash Flood Watch	10
Flood Watch	2
Areal Flood Advisory	12
Winter
Winter Storm Warning	3
Winter Weather Advisory	4
Heat
Excessive Heat Warning	1
Heat Advisory	4
Cold
Frost Advisory	3
Wind Chill Advisory	2
Wind and dust
Wind Advisory	2
Fog and smoke
Dense Fog Advisory	7

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2014 2016

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.