Alert archive / South Dakota / Perkins County

Weather alerts in Perkins County, South Dakota, 2021

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

Perkins County and its neighbors

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

Alerts: 151
Warnings: 67
Watches: 24
Advisories: 29
Busiest month: July29 alerts
Busiest day: June 11, 20218 alerts

Over time

By month

Warning verification

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

2 of 2 tornado warnings covering Perkins County in 2021 had a tornado report inside them; 4 of 4 tornado reports fell inside a warning, on average 32 minutes after it went out.

Perkins County, 2021

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	2	2	0%	4	100%	32 min
Severe thunderstorm warnings	37	29	22%	31	94%	26 min
Flash flood warnings	0			0

Each office's whole area, 2021

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Rapid City, SD: tornado warnings	5	3	40%	7	86%	22 min
NWS Rapid City, SD: severe thunderstorm warnings	212	171	19%	380	79%	26 min
NWS Rapid City, SD: flash flood warnings	2	0	100%	0

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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Jan 3, 1:32 PM MST	Wind Advisory	UNR	10 hr
Jan 11, 1:23 PM MST	High Wind Watch	UNR	37 hr
Jan 13, 2:14 AM MST	High Wind Warning	UNR	58 hr
Jan 20, 1:28 AM MST	Wind Advisory	UNR	13 hr
Jan 29, 8:49 PM MST	Dense Fog Advisory	UNR	14 hr
Feb 1, 8:02 PM MST	Dense Fog Advisory	UNR	15 hr
Feb 2, 5:55 PM MST	Dense Fog Advisory	UNR	16 hr
Feb 5, 6:44 PM MST	Wind Chill Advisory	UNR	16 hr
Feb 6, 1:07 PM MST	Wind Chill Advisory	UNR	22 hr
Feb 7, 8:10 PM MST	Wind Chill Advisory	UNR	39 hr
Feb 9, 1:32 PM MST	Wind Chill Advisory	UNR	4 days
Feb 11, 1:50 PM MST	Wind Chill Warning	UNR	5 days
Feb 21, 1:41 PM MST	High Wind Warning	UNR	27 hr
Feb 21, 1:41 PM MST	Wind Advisory	UNR	27 hr
Feb 22, 2:23 PM MST	High Wind Warning	UNR	27 hr
Mar 6, 5:17 AM MST	Dense Fog Advisory	UNR	5 hr
Mar 14, 5:20 PM MDT	Mesoscale Discussion	SPC	6 hr
Mar 26, 2:00 PM MDT	Fire Weather Watch	UNR	37 hr
Mar 27, 2:24 AM MDT	High Wind Watch	UNR	36 hr
Mar 27, 1:56 PM MDT	Red Flag Warning	UNR	3 days
Mar 28, 2:23 AM MDT	High Wind Warning	UNR	46 hr
Mar 29, 2:45 PM MDT	Wind Advisory	UNR	29 hr
Mar 31, 3:01 AM MDT	Fire Weather Watch	UNR	11 hr
Mar 31, 1:37 PM MDT	Red Flag Warning	UNR	53 hr
Apr 1, 2:16 PM MDT	Red Flag Warning	UNR	29 hr
Apr 3, 2:34 AM MDT	Red Flag Warning	UNR	16 hr
Apr 5, 3:13 AM MDT	Red Flag Warning	UNR	16 hr
Apr 8, 2:31 PM MDT	Wind Advisory	UNR	25 hr
Apr 9, 3:21 AM MDT	Red Flag Warning	UNR	16 hr
Apr 10, 2:27 PM MDT	High Wind Warning	UNR	16 hr
Apr 10, 2:27 PM MDT	Wind Advisory	UNR	3 days
Apr 29, 2:23 AM MDT	Fire Weather Watch	UNR	24 hr
Apr 29, 2:23 PM MDT	Red Flag Warning	UNR	30 hr
May 23, 12:58 PM MDT	Mesoscale Discussion	SPC	2 hr
May 23, 1:50 PM MDT	Tornado Watch	SPC	7 hr
May 23, 3:13 PM MDT	Tornado Warning	UNR	47 min
May 23, 3:58 PM MDT	Tornado Warning	UNR	47 min
May 23, 5:25 PM MDT	Mesoscale Discussion	SPC	95 min
May 23, 5:35 PM MDT	Special Weather Statement	UNR	40 min
May 24, 1:31 PM MDT	Wind Advisory	UNR	28 hr
Jun 4, 4:09 PM MDT	Special Weather Statement	UNR	51 min
Jun 8, 2:24 PM MDT	Mesoscale Discussion	SPC	96 min
Jun 8, 3:32 PM MDT	Special Weather Statement	UNR	43 min
Jun 8, 4:22 PM MDT	Special Weather Statement	UNR	53 min
Jun 8, 4:45 PM MDT	Special Weather Statement	UNR	30 min
Jun 8, 4:54 PM MDT	Severe Thunderstorm Warning	UNR	66 min
Jun 8, 7:00 PM MDT	Severe Thunderstorm Watch	SPC	5 hr
Jun 8, 8:20 PM MDT	Severe Thunderstorm Warning	UNR	55 min
Jun 8, 8:50 PM MDT	Mesoscale Discussion	SPC	85 min
Jun 8, 9:10 PM MDT	Severe Thunderstorm Warning	UNR	29 min
Jun 8, 9:25 PM MDT	Special Weather Statement	UNR	35 min
Jun 8, 10:17 PM MDT	Special Weather Statement	UNR	58 min
Jun 8, 10:50 PM MDT	Severe Thunderstorm Warning	UNR	55 min
Jun 10, 2:51 PM MDT	Mesoscale Discussion	SPC	114 min
Jun 10, 3:01 PM MDT	Wind Advisory	UNR	15 hr
Jun 10, 7:28 PM MDT	Mesoscale Discussion	SPC	92 min
Jun 10, 8:08 PM MDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 10, 8:38 PM MDT	Severe Thunderstorm Warning	UNR	67 min
Jun 10, 9:02 PM MDT	Severe Thunderstorm Warning	UNR	43 min
Jun 10, 9:29 PM MDT	Severe Thunderstorm Warning	UNR	61 min
Jun 10, 9:42 PM MDT	Severe Thunderstorm Warning	UNR	78 min
Jun 10, 10:07 PM MDT	Mesoscale Discussion	SPC	83 min
Jun 10, 10:44 PM MDT	Severe Thunderstorm Warning	UNR	76 min
Jun 16, 2:22 AM MDT	Wind Advisory	UNR	13 hr
Jul 3, 2:34 PM MDT	Mesoscale Discussion	SPC	116 min
Jul 5, 12:34 PM MDT	Mesoscale Discussion	SPC	116 min
Jul 5, 4:47 PM MDT	Special Weather Statement	UNR	28 min
Jul 5, 5:12 PM MDT	Severe Thunderstorm Warning	UNR	41 min
Jul 5, 6:41 PM MDT	Special Weather Statement	UNR	34 min
Jul 6, 5:08 PM MDT	Severe Thunderstorm Warning	UNR	67 min
Jul 6, 5:58 PM MDT	Severe Thunderstorm Warning	UNR	60 min
Jul 8, 2:34 PM MDT	Mesoscale Discussion	SPC	86 min
Jul 8, 3:49 PM MDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 8, 4:56 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 8, 5:30 PM MDT	Severe Thunderstorm Warning	UNR	26 min
Jul 8, 6:08 PM MDT	Mesoscale Discussion	SPC	97 min
Jul 8, 6:39 PM MDT	Severe Thunderstorm Warning	UNR	66 min
Jul 8, 6:58 PM MDT	Severe Thunderstorm Warning	UNR	47 min
Jul 8, 7:42 PM MDT	Severe Thunderstorm Warning	UNR	63 min
Jul 8, 7:43 PM MDT	Severe Thunderstorm Warning	UNR	62 min
Jul 8, 8:34 PM MDT	Severe Thunderstorm Warning	UNR	56 min
Jul 22, 4:01 PM MDT	Severe Thunderstorm Warning	UNR	59 min
Jul 22, 4:42 PM MDT	Mesoscale Discussion	SPC	3 hr
Jul 22, 4:48 PM MDT	Severe Thunderstorm Warning	UNR	57 min
Jul 22, 5:41 PM MDT	Severe Thunderstorm Warning	UNR	79 min
Jul 23, 4:04 PM MDT	Mesoscale Discussion	SPC	3 hr
Jul 23, 5:03 PM MDT	Special Weather Statement	UNR	42 min
Jul 23, 5:25 PM MDT	Severe Thunderstorm Warning	UNR	44 min
Jul 23, 6:02 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 23, 6:08 PM MDT	Special Weather Statement	UNR	67 min
Jul 23, 6:23 PM MDT	Severe Thunderstorm Warning	UNR	40 min
Jul 23, 7:15 PM MDT	Severe Thunderstorm Warning	UNR	30 min
Jul 26, 2:03 AM MDT	Heat Advisory	UNR	66 hr
Aug 6, 1:43 PM MDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 9, 3:36 AM MDT	Fire Weather Watch	UNR	24 hr
Aug 10, 3:10 AM MDT	Red Flag Warning	UNR	18 hr
Aug 16, 1:41 PM MDT	Fire Weather Watch	UNR	13 hr
Aug 16, 1:41 PM MDT	Red Flag Warning	UNR	30 hr
Aug 19, 5:26 PM MDT	Severe Thunderstorm Warning	UNR	79 min
Aug 23, 5:17 PM MDT	Severe Thunderstorm Warning Considerable damage threat	UNR	58 min
Aug 26, 1:35 AM MDT	Mesoscale Discussion	SPC	2 hr
Aug 26, 2:06 AM MDT	Special Weather Statement	UNR	54 min
Aug 26, 2:18 AM MDT	Severe Thunderstorm Warning	UNR	42 min
Aug 27, 2:55 PM MDT	Mesoscale Discussion	SPC	2 hr
Aug 27, 5:33 PM MDT	Mesoscale Discussion	SPC	117 min
Aug 27, 5:39 PM MDT	Severe Thunderstorm Warning Considerable damage threat	UNR	96 min
Aug 27, 7:14 PM MDT	Severe Thunderstorm Warning	UNR	46 min
Aug 30, 3:03 PM MDT	Severe Thunderstorm Watch	SPC	6 hr
Aug 30, 3:34 PM MDT	Severe Thunderstorm Warning	UNR	56 min
Aug 30, 4:29 PM MDT	Severe Thunderstorm Warning Considerable damage threat	UNR	61 min
Aug 30, 5:06 PM MDT	Severe Thunderstorm Warning Destructive damage threat	UNR	54 min
Aug 30, 5:45 PM MDT	Severe Thunderstorm Warning Destructive damage threat	UNR	60 min
Aug 30, 5:53 PM MDT	Severe Thunderstorm Warning Considerable damage threat	UNR	67 min
Aug 30, 6:42 PM MDT	Severe Thunderstorm Warning Destructive damage threat	UNR	63 min
Aug 30, 6:56 PM MDT	Severe Thunderstorm Warning Considerable damage threat	UNR	64 min
Aug 30, 8:19 PM MDT	Special Weather Statement	UNR	41 min
Aug 30, 9:08 PM MDT	Severe Thunderstorm Warning	UNR	35 min
Sep 4, 1:39 PM MDT	Fire Weather Watch	UNR	24 hr
Sep 5, 1:44 PM MDT	Red Flag Warning	UNR	29 hr
Sep 14, 1:27 PM MDT	Fire Weather Watch	UNR	14 hr
Sep 15, 3:09 AM MDT	Red Flag Warning	UNR	16 hr
Sep 17, 2:44 AM MDT	Fire Weather Watch	UNR	11 hr
Sep 17, 1:17 PM MDT	Red Flag Warning	UNR	32 hr
Sep 19, 2:36 AM MDT	Wind Advisory	UNR	23 hr
Sep 23, 1:58 PM MDT	Fire Weather Watch	UNR	12 hr
Sep 24, 1:33 AM MDT	Red Flag Warning	UNR	16 hr
Sep 27, 1:45 AM MDT	Fire Weather Watch	UNR	11 hr
Sep 27, 1:01 PM MDT	Red Flag Warning	UNR	30 hr
Oct 5, 1:49 PM MDT	Fire Weather Watch	UNR	13 hr
Oct 6, 2:36 AM MDT	Red Flag Warning	UNR	16 hr
Oct 12, 2:03 PM MDT	Wind Advisory	UNR	28 hr
Oct 13, 2:45 PM MDT	Freeze Warning	UNR	18 hr
Oct 25, 1:33 AM MDT	Dense Fog Advisory	UNR	7 hr
Nov 10, 1:01 AM MST	Wind Advisory	UNR	16 hr
Nov 10, 8:03 AM MST	High Wind Warning	UNR	39 hr
Nov 10, 1:10 PM MST	Wind Advisory	UNR	40 hr
Nov 12, 1:20 PM MST	High Wind Watch	UNR	13 hr
Nov 13, 2:05 AM MST	High Wind Warning	UNR	18 hr
Nov 15, 1:31 AM MST	High Wind Watch	UNR	13 hr
Nov 15, 1:46 AM MST	Fire Weather Watch	UNR	13 hr
Nov 15, 2:25 PM MST	High Wind Warning	UNR	51 hr
Nov 15, 2:28 PM MST	Red Flag Warning	UNR	27 hr
Nov 30, 7:52 PM MST	Wind Advisory	UNR	21 hr
Dec 4, 2:00 AM MST	High Wind Watch	UNR	12 hr
Dec 4, 2:04 PM MST	High Wind Warning	UNR	27 hr
Dec 14, 2:33 AM MST	High Wind Warning	UNR	42 hr
Dec 14, 1:45 PM MST	Winter Weather Advisory	UNR	30 hr
Dec 26, 10:12 AM MST	Winter Weather Advisory	UNR	22 hr
Dec 27, 8:06 AM MST	Wind Chill Advisory	UNR	4 hr
Dec 27, 12:22 PM MST	Wind Chill Advisory	UNR	20 hr
Dec 30, 1:29 PM MST	Wind Chill Advisory	UNR	28 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	37
Tornado Warning	2
Severe Thunderstorm Watch	6
Tornado Watch	1
Mesoscale Discussion	18
Special Weather Statement	13
Winter
Winter Weather Advisory	2
Heat
Heat Advisory	1
Cold
Freeze Warning	1
Wind Chill Warning	1
Wind Chill Advisory	7
Wind and dust
High Wind Warning	10
High Wind Watch	5
Wind Advisory	14
Fire
Red Flag Warning	16
Fire Weather Watch	12
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 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.