Weather alerts in Sioux County, Iowa, 2026

143 weather alerts in 2026, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Sioux County and its neighbors

Each county as a circle sized by its count in 2026. Tap one for its archive.

Alerts: 143
Warnings: 56
Watches: 26
Advisories: 28
Busiest month: July28 alerts
Busiest day: July 26, 202611 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 1 tornado warnings covering Sioux County in 2026 had a tornado report inside them.

Sioux County, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	1	0	100%	0
Severe thunderstorm warnings	37	25	32%	25	72%	21 min
Flash flood warnings	1	1	0%	0

Each office's whole area, 2026

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Sioux Falls, SD: tornado warnings	40	13	68%	23	65%	12 min
NWS Sioux Falls, SD: severe thunderstorm warnings	292	194	34%	549	89%	21 min
NWS Sioux Falls, SD: flash flood warnings	16	4	75%	5	80%	12 min

An office's figures cover every county it serves, including across state lines.

The year is still running; reports filed late and damage surveys can still change these figures.

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 5, 9:42 PM CST	Dense Fog Advisory	FSD	9 hr
Jan 15, 1:59 PM CST	Winter Weather Advisory	FSD	34 hr
Jan 17, 2:21 PM CST	Winter Weather Advisory	FSD	34 hr
Jan 20, 1:23 PM CST	Extreme Cold Watch	FSD	37 hr
Jan 20, 1:23 PM CST	Wind Advisory	FSD	21 hr
Jan 20, 1:23 PM CST	Winter Weather Advisory	FSD	29 hr
Jan 21, 10:42 AM CST	High Wind Warning	FSD	7 hr
Jan 22, 2:28 AM CST	Extreme Cold Warning	FSD	33 hr
Jan 23, 2:17 AM CST	Cold Weather Advisory	FSD	31 hr
Jan 25, 2:13 AM CST	Cold Weather Advisory	FSD	32 hr
Feb 17, 2:43 AM CST	Wind Advisory	FSD	36 hr
Feb 17, 2:38 PM CST	Fire Weather Watch	FSD	7 hr
Feb 17, 5:22 PM CST	Mesoscale Discussion	SPC	53 min
Feb 17, 10:06 PM CST	Red Flag Warning	FSD	20 hr
Feb 18, 12:59 PM CST	Winter Weather Advisory	FSD	35 hr
Feb 26, 9:28 PM CST	Red Flag Warning	FSD	21 hr
Mar 3, 11:43 PM CST	Dense Fog Advisory	FSD	8 hr
Mar 4, 8:30 AM CST	Dense Fog Advisory	FSD	3 hr
Mar 5, 1:55 PM CST	Winter Weather Advisory	FSD	41 hr
Mar 6, 6:22 AM CST	Dense Fog Advisory	FSD	5 hr
Mar 10, 11:57 PM CDT	High Wind Watch	FSD	21 hr
Mar 11, 12:01 AM CDT	Fire Weather Watch	FSD	21 hr
Mar 11, 1:59 PM CDT	High Wind Warning	FSD	41 hr
Mar 11, 8:50 PM CDT	Red Flag Warning	FSD	23 hr
Mar 12, 2:35 PM CDT	Winter Storm Watch	FSD	47 hr
Mar 13, 9:20 PM CDT	Blizzard Warning	FSD	56 hr
Mar 14, 1:11 PM CDT	High Wind Warning	FSD	36 hr
Mar 15, 9:49 AM CDT	Mesoscale Discussion	SPC	6 hr
Mar 15, 2:31 PM CDT	Cold Weather Advisory	FSD	20 hr
Mar 26, 1:57 PM CDT	Fire Weather Watch	FSD	21 hr
Mar 27, 11:17 AM CDT	Red Flag Warning	FSD	34 hr
Apr 11, 1:52 PM CDT	Red Flag Warning	FSD	29 hr
Apr 13, 2:42 PM CDT	Mesoscale Discussion	SPC	93 min
Apr 13, 4:39 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Apr 13, 5:26 PM CDT	Severe Thunderstorm Warning	FSD	49 min
Apr 13, 6:05 PM CDT	Severe Thunderstorm Warning	FSD	40 min
Apr 15, 12:28 PM CDT	Fire Weather Watch	FSD	9 hr
Apr 15, 12:28 PM CDT	Red Flag Warning	FSD	32 hr
Apr 21, 12:54 PM CDT	Red Flag Warning	FSD	31 hr
Apr 23, 11:13 AM CDT	Mesoscale Discussion	SPC	2 hr
Apr 23, 12:02 PM CDT	Tornado Watch	SPC	7 hr
Apr 30, 1:36 PM CDT	Frost Advisory	FSD	18 hr
May 1, 1:06 PM CDT	Freeze Warning	FSD	19 hr
May 5, 1:19 PM CDT	Frost Advisory	FSD	18 hr
May 10, 1:08 PM CDT	Frost Advisory	FSD	19 hr
May 11, 3:07 PM CDT	Red Flag Warning	FSD	30 hr
May 13, 1:54 PM CDT	Red Flag Warning	FSD	30 hr
May 15, 3:55 PM CDT	Mesoscale Discussion	SPC	2 hr
May 15, 5:16 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
May 15, 6:08 PM CDT	Severe Thunderstorm Warning	FSD	52 min
May 15, 7:29 PM CDT	Mesoscale Discussion	SPC	2 hr
May 17, 1:11 PM CDT	Mesoscale Discussion	SPC	2 hr
May 17, 1:42 PM CDT	Tornado Watch	SPC	8 hr
May 17, 3:31 PM CDT	Mesoscale Discussion	SPC	89 min
May 17, 5:56 PM CDT	Severe Thunderstorm Warning	FSD	27 min
May 17, 6:33 PM CDT	Severe Thunderstorm Warning	FSD	57 min
May 17, 7:20 PM CDT	Severe Thunderstorm Warning	FSD	28 min
May 17, 8:00 PM CDT	Severe Thunderstorm Warning	FSD	45 min
May 17, 8:03 PM CDT	Flash Flood Warning	FSD	3 hr
May 18, 5:10 PM CDT	Mesoscale Discussion	SPC	95 min
May 18, 6:08 PM CDT	Severe Thunderstorm Warning	FSD	37 min
May 19, 2:43 AM CDT	Frost Advisory	FSD	29 hr
May 24, 3:34 PM CDT	Mesoscale Discussion	SPC	86 min
May 24, 4:53 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
May 24, 6:49 PM CDT	Mesoscale Discussion	SPC	116 min
May 24, 8:48 PM CDT	Mesoscale Discussion	SPC	87 min
May 25, 1:12 AM CDT	Severe Thunderstorm Warning	FSD	48 min
May 25, 7:13 PM CDT	Mesoscale Discussion	SPC	92 min
May 31, 3:20 PM CDT	Mesoscale Discussion	SPC	2 hr
May 31, 9:15 PM CDT	Mesoscale Discussion	SPC	2 hr
May 31, 9:38 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
May 31, 10:46 PM CDT	Mesoscale Discussion	SPC	119 min
Jun 8, 2:01 PM CDT	Heat Advisory	FSD	30 hr
Jun 9, 8:36 PM CDT	Tornado Watch	SPC	5 hr
Jun 16, 12:40 PM CDT	Wind Advisory	FSD	31 hr
Jun 16, 11:28 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 17, 2:36 AM CDT	Mesoscale Discussion	SPC	2 hr
Jun 17, 3:55 AM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 17, 5:10 PM CDT	Severe Thunderstorm Warning	FSD	50 min
Jun 17, 5:54 PM CDT	Severe Thunderstorm Warning	FSD	51 min
Jun 27, 12:59 AM CDT	Heat Advisory	FSD	68 hr
Jun 28, 2:37 AM CDT	Mesoscale Discussion	SPC	113 min
Jun 28, 4:37 AM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	53 min
Jun 28, 4:51 AM CDT	Severe Thunderstorm Watch	SPC	4 hr
Jun 28, 5:00 AM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	60 min
Jun 28, 5:58 AM CDT	Severe Thunderstorm Warning	FSD	62 min
Jun 29, 12:42 AM CDT	Extreme Heat Warning	FSD	20 hr
Jun 29, 4:00 PM CDT	Mesoscale Discussion	SPC	3 hr
Jun 29, 6:33 PM CDT	Severe Thunderstorm Watch	SPC	5 hr
Jun 29, 8:59 PM CDT	Mesoscale Discussion	SPC	91 min
Jun 29, 11:55 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
Jun 30, 12:43 AM CDT	Severe Thunderstorm Warning	FSD	19 min
Jun 30, 1:14 AM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	46 min
Jun 30, 1:34 AM CDT	Severe Thunderstorm Warning	FSD	26 min
Jun 30, 1:42 AM CDT	Mesoscale Discussion	SPC	93 min
Jun 30, 1:54 AM CDT	Severe Thunderstorm Warning	FSD	51 min
Jul 1, 2:05 AM CDT	Severe Thunderstorm Warning	FSD	25 min
Jul 1, 2:24 AM CDT	Severe Thunderstorm Warning	FSD	51 min
Jul 1, 2:42 AM CDT	Severe Thunderstorm Warning	FSD	33 min
Jul 1, 3:06 AM CDT	Severe Thunderstorm Warning	FSD	39 min
Jul 1, 3:29 AM CDT	Mesoscale Discussion	SPC	91 min
Jul 1, 6:11 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 1, 7:38 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 2, 8:48 AM CDT	Severe Thunderstorm Warning	FSD	42 min
Jul 2, 1:17 PM CDT	Flood Watch	FSD	16 hr
Jul 2, 5:52 PM CDT	Mesoscale Discussion	SPC	83 min
Jul 2, 6:08 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 2, 8:47 PM CDT	Mesoscale Discussion	SPC	118 min
Jul 2, 11:37 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 17, 1:31 AM CDT	Heat Advisory	FSD	19 hr
Jul 19, 1:05 PM CDT	Heat Advisory	FSD	31 hr
Jul 24, 11:23 AM CDT	Heat Advisory	FSD	29 hr
Jul 24, 11:24 PM CDT	Extreme Heat Warning	FSD	46 hr
Jul 25, 7:45 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 25, 7:58 PM CDT	Severe Thunderstorm Watch	SPC	4 hr
Jul 25, 8:33 PM CDT	Severe Thunderstorm Warning	FSD	42 min
Jul 25, 8:42 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	48 min
Jul 25, 8:53 PM CDT	Severe Thunderstorm Warning Destructive damage threat	FSD	37 min
Jul 25, 9:07 PM CDT	Mesoscale Discussion	SPC	83 min
Jul 25, 9:09 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	51 min
Jul 25, 9:26 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	34 min
Jul 25, 9:49 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	41 min
Jul 25, 9:53 PM CDT	Severe Thunderstorm Warning	FSD	37 min
Jul 26, 12:39 PM CDT	Heat Advisory	FSD	31 hr
Aug 6, 12:55 AM CDT	Dense Fog Advisory	FSD	9 hr
Aug 11, 1:15 AM CDT	Mesoscale Discussion	SPC	2 hr
Aug 11, 4:15 AM CDT	Severe Thunderstorm Warning	FSD	35 min
Aug 18, 2:47 PM CDT	Mesoscale Discussion	SPC	118 min
Aug 29, 5:08 AM CDT	Severe Thunderstorm Warning	FSD	8 min
Sep 1, 3:50 PM CDT	Severe Thunderstorm Watch	SPC	9 hr
Sep 1, 9:11 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 1, 9:24 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	51 min
Sep 1, 9:50 PM CDT	Severe Thunderstorm Watch	SPC	7 hr
Sep 1, 10:02 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	43 min
Sep 1, 10:04 PM CDT	Tornado Warning	FSD	26 min
Sep 1, 10:34 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	71 min
Sep 3, 2:34 AM CDT	Mesoscale Discussion	SPC	116 min
Sep 4, 7:42 AM CDT	Heat Advisory	FSD	10 hr
Sep 6, 10:23 AM CDT	Flood Watch	FSD	9 hr
Sep 7, 11:42 PM CDT	Severe Thunderstorm Warning	FSD	48 min
Sep 8, 11:39 PM CDT	Dense Fog Advisory	FSD	8 hr
Sep 11, 8:36 PM CDT	Mesoscale Discussion	SPC	114 min
Sep 11, 9:24 PM CDT	Severe Thunderstorm Warning Considerable damage threat	FSD	51 min

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	37
Tornado Warning	1
Severe Thunderstorm Watch	14
Tornado Watch	3
Mesoscale Discussion	33
Flooding
Flash Flood Warning	1
Flood Watch	2
Winter
Blizzard Warning	1
Winter Storm Watch	1
Winter Weather Advisory	5
Heat
Extreme Heat Warning	2
Heat Advisory	7
Cold
Extreme Cold Warning	1
Freeze Warning	1
Extreme Cold Watch	1
Cold Weather Advisory	3
Frost Advisory	4
Wind and dust
High Wind Warning	3
High Wind Watch	1
Wind Advisory	3
Fire
Red Flag Warning	9
Fire Weather Watch	4
Fog and smoke
Dense Fog 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 2025

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.