Alert archive / South Dakota / Fall River County

Weather alerts in Fall River County, South Dakota, 2011

127 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Fall River County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts: 127
Warnings: 38
Watches: 26
Advisories: 26
Busiest month: June32 alerts
Busiest day: June 12, 20119 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 Fall River County in 2011 had a tornado report inside them.

Fall River County, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	1	0	100%	0
Severe thunderstorm warnings	24	16	33%	13	77%	18 min
Flash flood warnings	5	1	80%	1	100%	26 min

Each office's whole area, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Rapid City, SD: tornado warnings	23	2	91%	5	40%	55 min
NWS Rapid City, SD: severe thunderstorm warnings	426	315	26%	626	88%	25 min
NWS Rapid City, SD: flash flood warnings	30	10	67%	16	94%	70 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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Dec 31, 10:00 PM MST	Wind Chill Advisory	UNR	12 hr
Jan 7, 2:38 AM MST	Winter Storm Watch	UNR	11 hr
Jan 7, 1:26 PM MST	Winter Weather Advisory	UNR	58 hr
Jan 18, 2:02 PM MST	Winter Weather Advisory	UNR	21 hr
Jan 29, 2:03 PM MST	Winter Weather Advisory	UNR	48 hr
Jan 29, 5:06 PM MST	Freezing Fog Advisory	UNR	16 hr
Jan 31, 2:44 AM MST	Wind Chill Warning	UNR	33 hr
Feb 1, 4:09 AM MST	Wind Chill Advisory	UNR	16 hr
Feb 1, 2:54 PM MST	Wind Chill Warning	UNR	19 hr
Feb 2, 3:10 AM MST	Wind Chill Advisory	UNR	7 hr
Feb 6, 2:39 PM MST	Winter Weather Advisory	UNR	30 hr
Feb 8, 2:41 PM MST	Wind Chill Advisory	UNR	19 hr
Feb 12, 3:05 PM MST	Wind Advisory	UNR	28 hr
Feb 16, 2:39 PM MST	Wind Advisory	UNR	26 hr
Feb 18, 1:56 PM MST	Winter Storm Watch	UNR	13 hr
Feb 19, 2:35 AM MST	Winter Storm Warning	UNR	44 hr
Feb 23, 2:26 PM MST	Winter Weather Advisory	UNR	38 hr
Feb 24, 2:48 PM MST	Wind Chill Advisory	UNR	13 hr
Feb 25, 4:01 AM MST	Winter Weather Advisory	UNR	24 hr
Mar 5, 2:03 PM MST	Winter Storm Watch	UNR	13 hr
Mar 6, 2:40 AM MST	Winter Weather Advisory	UNR	32 hr
Apr 13, 4:32 AM MDT	Winter Storm Watch	UNR	24 hr
Apr 14, 4:07 AM MDT	Winter Weather Advisory	UNR	24 hr
Apr 21, 2:48 PM MDT	Wind Advisory	UNR	33 hr
Apr 22, 1:48 PM MDT	High Wind Warning	UNR	5 hr
Apr 30, 10:10 AM MDT	Wind Advisory	UNR	9 hr
May 9, 2:26 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
May 9, 4:57 PM MDT	Mesoscale Discussion	SPC	93 min
May 9, 6:49 PM MDT	Flash Flood Warning	UNR	4 hr
May 9, 6:58 PM MDT	Severe Thunderstorm Warning	UNR	62 min
May 9, 8:04 PM MDT	Tornado Warning	UNR	56 min
May 9, 8:16 PM MDT	Mesoscale Discussion	SPC	29 min
May 9, 10:19 PM MDT	Areal Flood Warning	UNR	16 hr
May 16, 2:59 PM MDT	Flash Flood Watch	UNR	4 days
May 20, 9:43 PM MDT	Areal Flood Warning	UNR	23 hr
May 22, 2:56 PM MDT	Flood Watch	UNR	60 hr
May 27, 2:49 PM MDT	Flood Watch	UNR	61 hr
Jun 6, 3:50 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 6, 7:10 PM MDT	Mesoscale Discussion	SPC	95 min
Jun 9, 7:09 PM MDT	Mesoscale Discussion	SPC	96 min
Jun 11, 1:40 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 11, 3:59 PM MDT	Tornado Watch	SPC	7 hr
Jun 11, 4:59 PM MDT	Severe Thunderstorm Warning	UNR	61 min
Jun 11, 5:21 PM MDT	Flash Flood Warning	UNR	4 hr
Jun 11, 7:11 PM MDT	Mesoscale Discussion	SPC	64 min
Jun 12, 10:02 AM MDT	Flash Flood Watch	UNR	10 hr
Jun 12, 12:52 PM MDT	Mesoscale Discussion	SPC	53 min
Jun 12, 1:49 PM MDT	Tornado Watch	SPC	6 hr
Jun 12, 3:01 PM MDT	Severe Thunderstorm Warning	UNR	59 min
Jun 12, 4:04 PM MDT	Flash Flood Warning	UNR	3 hr
Jun 12, 4:09 PM MDT	Severe Thunderstorm Warning	UNR	66 min
Jun 12, 4:37 PM MDT	Severe Thunderstorm Warning	UNR	53 min
Jun 12, 5:19 PM MDT	Severe Thunderstorm Warning	UNR	56 min
Jun 13, 4:24 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 18, 4:38 PM MDT	Severe Thunderstorm Warning	UNR	52 min
Jun 24, 1:25 PM MDT	Mesoscale Discussion	SPC	65 min
Jun 24, 1:52 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 24, 7:11 PM MDT	Severe Thunderstorm Warning	UNR	64 min
Jun 25, 1:24 PM MDT	Mesoscale Discussion	SPC	96 min
Jun 25, 5:21 PM MDT	Mesoscale Discussion	SPC	84 min
Jun 25, 6:33 PM MDT	Severe Thunderstorm Warning	UNR	57 min
Jun 25, 6:53 PM MDT	Severe Thunderstorm Warning	UNR	42 min
Jun 25, 7:00 PM MDT	Severe Thunderstorm Warning	UNR	30 min
Jun 26, 1:30 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 26, 2:22 PM MDT	Severe Thunderstorm Warning	UNR	53 min
Jun 26, 3:37 PM MDT	Severe Thunderstorm Warning	UNR	53 min
Jun 26, 4:32 PM MDT	Severe Thunderstorm Warning	UNR	58 min
Jun 26, 5:46 PM MDT	Severe Thunderstorm Warning	UNR	59 min
Jun 26, 5:49 PM MDT	Flash Flood Warning	UNR	65 min
Jun 30, 7:25 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 2, 12:17 PM MDT	Mesoscale Discussion	SPC	58 min
Jul 2, 2:13 PM MDT	Tornado Watch	SPC	8 hr
Jul 2, 4:59 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 2, 6:37 PM MDT	Severe Thunderstorm Warning	UNR	53 min
Jul 2, 6:47 PM MDT	Flash Flood Warning	UNR	67 min
Jul 2, 6:48 PM MDT	Mesoscale Discussion	SPC	117 min
Jul 2, 7:02 PM MDT	Severe Thunderstorm Warning	UNR	43 min
Jul 2, 7:27 PM MDT	Severe Thunderstorm Warning	UNR	63 min
Jul 4, 2:51 PM MDT	Mesoscale Discussion	SPC	54 min
Jul 4, 3:45 PM MDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 4, 6:46 PM MDT	Severe Thunderstorm Warning	UNR	33 min
Jul 4, 6:59 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 5, 1:17 PM MDT	Mesoscale Discussion	SPC	73 min
Jul 8, 3:29 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 8, 3:48 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 11, 1:50 PM MDT	Mesoscale Discussion	SPC	85 min
Jul 11, 2:07 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 11, 4:01 PM MDT	Mesoscale Discussion	SPC	29 min
Jul 11, 4:06 PM MDT	Tornado Watch	SPC	5 hr
Jul 11, 4:14 PM MDT	Severe Thunderstorm Warning	UNR	61 min
Jul 24, 2:06 PM MDT	Mesoscale Discussion	SPC	84 min
Jul 25, 11:23 AM MDT	Mesoscale Discussion	SPC	97 min
Jul 25, 1:30 PM MDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 27, 2:49 PM MDT	Mesoscale Discussion	SPC	86 min
Jul 27, 6:27 PM MDT	Severe Thunderstorm Warning	UNR	63 min
Jul 29, 12:59 PM MDT	Mesoscale Discussion	SPC	91 min
Jul 29, 1:54 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 29, 4:46 PM MDT	Mesoscale Discussion	SPC	59 min
Aug 3, 1:01 PM MDT	Mesoscale Discussion	SPC	89 min
Aug 5, 4:25 PM MDT	Mesoscale Discussion	SPC	2 hr
Aug 7, 1:58 PM MDT	Severe Thunderstorm Watch	SPC	8 hr
Aug 8, 2:09 PM MDT	Mesoscale Discussion	SPC	66 min
Aug 9, 9:25 AM MDT	Mesoscale Discussion	SPC	95 min
Aug 9, 5:02 PM MDT	Mesoscale Discussion	SPC	118 min
Aug 10, 3:42 PM MDT	Mesoscale Discussion	SPC	63 min
Aug 11, 2:05 PM MDT	Tornado Watch	SPC	5 hr
Aug 11, 2:17 PM MDT	Severe Thunderstorm Warning	UNR	58 min
Aug 14, 1:59 PM MDT	Mesoscale Discussion	SPC	91 min
Aug 25, 3:59 PM MDT	Mesoscale Discussion	SPC	91 min
Aug 27, 4:14 PM MDT	Severe Thunderstorm Warning	UNR	49 min
Aug 29, 2:53 PM MDT	Severe Thunderstorm Warning	UNR	67 min
Sep 20, 8:00 PM MDT	Frost Advisory	UNR	11 hr
Sep 29, 11:03 AM MDT	Frost Advisory	UNR	21 hr
Oct 6, 2:07 PM MDT	Special Weather Statement	CYS	23 min
Oct 6, 2:18 PM MDT	Wind Advisory	UNR	29 hr
Oct 6, 2:19 PM MDT	Mesoscale Discussion	SPC	116 min
Oct 6, 2:32 PM MDT	Severe Thunderstorm Watch	SPC	9 hr
Oct 6, 4:55 PM MDT	Mesoscale Discussion	SPC	95 min
Oct 17, 2:52 PM MDT	Freeze Warning	UNR	18 hr
Oct 31, 2:52 PM MDT	Winter Weather Advisory	UNR	31 hr
Nov 17, 2:15 PM MST	Winter Storm Watch	UNR	22 hr
Nov 18, 12:19 PM MST	Winter Weather Advisory	UNR	26 hr
Nov 24, 2:18 PM MST	High Wind Watch	UNR	25 hr
Nov 25, 2:28 AM MST	Wind Advisory	UNR	37 hr
Dec 12, 2:18 PM MST	Dense Fog Advisory	UNR	13 hr
Dec 20, 2:46 PM MST	Winter Weather Advisory	UNR	32 hr
Dec 30, 2:36 PM MST	High Wind Warning	UNR	26 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	24
Tornado Warning	1
Severe Thunderstorm Watch	11
Tornado Watch	5
Mesoscale Discussion	36
Special Weather Statement	1
Flooding
Areal Flood Warning	2
Flash Flood Warning	5
Flash Flood Watch	2
Flood Watch	2
Winter
Winter Storm Warning	1
Winter Storm Watch	5
Winter Weather Advisory	11
Cold
Freeze Warning	1
Wind Chill Warning	2
Frost Advisory	2
Wind Chill Advisory	5
Wind and dust
High Wind Warning	2
High Wind Watch	1
Wind Advisory	6
Fog and smoke
Dense Fog Advisory	1
Freezing Fog Advisory	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 2010 2012

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.