Alert archive / Montana / Sweet Grass County

Weather alerts in Sweet Grass County, Montana, 2011

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

Sweet Grass County and its neighbors

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

Alerts: 170
Warnings: 52
Watches: 33
Advisories: 42
Busiest month: July31 alerts
Busiest day: June 7, 201110 alerts

Over time

By month

Warning verification

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

Sweet Grass County, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			0
Severe thunderstorm warnings	11	6	45%	12	83%	21 min
Flash flood warnings	1	1	0%	0

Each office's whole area, 2011

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Billings, MT: tornado warnings	13	5	62%	8	75%	21 min
NWS Billings, MT: severe thunderstorm warnings	171	76	56%	190	74%	21 min
NWS Billings, MT: flash flood warnings	21	5	76%	7	100%	40 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, 8:39 PM MST	Wind Chill Advisory	BYZ	14 hr
Jan 1, 3:46 AM MST	Winter Weather Advisory	BYZ	49 hr
Jan 4, 4:01 AM MST	Wind Advisory	BYZ	59 hr
Jan 12, 8:07 AM MST	Wind Advisory	BYZ	21 hr
Jan 15, 3:00 PM MST	High Wind Watch	BYZ	12 hr
Jan 16, 3:07 AM MST	Wind Advisory	BYZ	20 hr
Jan 18, 4:09 AM MST	Winter Storm Warning	BYZ	32 hr
Jan 18, 4:09 AM MST	Winter Weather Advisory	BYZ	32 hr
Jan 19, 2:56 PM MST	Blizzard Watch	BYZ	12 hr
Jan 20, 3:06 AM MST	Blizzard Warning	BYZ	24 hr
Jan 20, 3:46 PM MST	Wind Advisory	BYZ	11 hr
Jan 22, 3:26 PM MST	Wind Advisory	BYZ	25 hr
Jan 27, 3:59 AM MST	Wind Advisory	BYZ	31 hr
Jan 28, 3:17 PM MST	Winter Weather Advisory	BYZ	60 hr
Jan 31, 3:33 AM MST	Wind Chill Advisory	BYZ	25 hr
Feb 1, 11:08 PM MST	Wind Chill Advisory	BYZ	11 hr
Feb 3, 2:55 PM MST	Wind Advisory	BYZ	30 hr
Feb 4, 2:51 PM MST	Winter Storm Warning	BYZ	24 hr
Feb 5, 3:10 PM MST	Winter Storm Watch	BYZ	24 hr
Feb 5, 9:22 PM MST	Winter Weather Advisory	BYZ	14 hr
Feb 6, 3:08 PM MST	Winter Storm Warning	BYZ	33 hr
Feb 6, 3:08 PM MST	Winter Weather Advisory	BYZ	33 hr
Feb 10, 1:47 PM MST	High Wind Watch	BYZ	38 hr
Feb 11, 3:46 AM MST	High Wind Warning	BYZ	62 hr
Feb 14, 4:35 AM MST	High Wind Watch	BYZ	10 hr
Feb 14, 2:20 PM MST	Wind Advisory	BYZ	31 hr
Feb 19, 3:47 AM MST	Winter Weather Advisory	BYZ	38 hr
Feb 26, 2:47 AM MST	Wind Chill Advisory	BYZ	8 hr
Feb 27, 10:05 AM MST	Wind Advisory	BYZ	12 hr
Feb 27, 10:30 PM MST	High Wind Warning	BYZ	25 hr
Mar 3, 3:08 PM MST	Winter Weather Advisory	BYZ	12 hr
Mar 5, 3:08 PM MST	Winter Weather Advisory	BYZ	32 hr
Mar 9, 2:25 PM MST	Wind Advisory	BYZ	31 hr
Mar 14, 2:19 AM MDT	Wind Advisory	BYZ	10 hr
Mar 15, 3:31 PM MDT	High Wind Warning	BYZ	13 hr
Mar 16, 3:59 AM MDT	Winter Storm Warning	BYZ	23 hr
Mar 21, 3:02 PM MDT	Winter Weather Advisory	BYZ	38 hr
Mar 22, 6:25 AM MDT	Winter Storm Warning	BYZ	23 hr
Mar 29, 3:23 AM MDT	Winter Storm Watch	BYZ	12 hr
Mar 29, 3:17 PM MDT	Winter Storm Warning	BYZ	60 hr
Apr 4, 10:47 AM MDT	Wind Advisory	BYZ	22 hr
Apr 5, 2:55 AM MDT	Winter Storm Warning	BYZ	18 hr
Apr 6, 3:40 PM MDT	Winter Storm Watch	BYZ	12 hr
Apr 6, 3:40 PM MDT	Winter Storm Warning	BYZ	53 hr
Apr 17, 4:34 AM MDT	Winter Storm Watch	BYZ	34 hr
Apr 18, 4:34 AM MDT	Winter Storm Warning	BYZ	35 hr
Apr 20, 3:25 PM MDT	Winter Storm Watch	BYZ	12 hr
Apr 21, 3:28 AM MDT	Winter Storm Warning	BYZ	38 hr
May 7, 3:31 PM MDT	Winter Storm Watch	BYZ	12 hr
May 8, 3:40 AM MDT	Winter Storm Warning	BYZ	62 hr
May 17, 3:35 PM MDT	Flood Watch	BYZ	5 days
May 18, 3:18 AM MDT	Winter Storm Watch	BYZ	24 hr
May 19, 3:14 AM MDT	Winter Storm Warning	BYZ	3 days
May 20, 3:50 PM MDT	Areal Flood Warning	BYZ	71 hr
May 23, 9:52 AM MDT	Flood Watch	BYZ	48 hr
May 23, 2:37 PM MDT	Areal Flood Warning	BYZ	3 days
May 24, 12:33 PM MDT	Areal Flood Warning	BYZ	69 hr
May 26, 3:41 PM MDT	Areal Flood Warning	BYZ	18 hr
May 27, 3:48 AM MDT	Flood Watch	BYZ	4 days
May 28, 3:52 AM MDT	Winter Storm Watch	BYZ	24 hr
May 29, 3:49 AM MDT	Winter Storm Warning	BYZ	40 hr
Jun 3, 4:03 PM MDT	River Flood Watch	BYZ	4 days
Jun 3, 4:03 PM MDT	River Flood Watch	BYZ	4 days
Jun 6, 2:13 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 6, 4:45 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 6, 5:46 PM MDT	Tornado Watch	SPC	7 hr
Jun 6, 6:33 PM MDT	Special Weather Statement	BYZ	57 min
Jun 6, 6:50 PM MDT	Severe Thunderstorm Warning	BYZ	55 min
Jun 6, 6:55 PM MDT	Severe Thunderstorm Warning	BYZ	65 min
Jun 6, 7:12 PM MDT	Severe Thunderstorm Warning	BYZ	33 min
Jun 6, 7:16 PM MDT	Severe Thunderstorm Warning	BYZ	59 min
Jun 6, 7:16 PM MDT	Severe Thunderstorm Warning	BYZ	21 min
Jun 6, 7:45 PM MDT	Severe Thunderstorm Warning	BYZ	30 min
Jun 6, 8:03 PM MDT	Flash Flood Warning	BYZ	3 hr
Jun 6, 8:25 PM MDT	Mesoscale Discussion	SPC	95 min
Jun 6, 11:50 PM MDT	Special Weather Statement	BYZ	55 min
Jun 9, 2:58 AM MDT	Flood Watch	BYZ	13 hr
Jun 15, 1:22 PM MDT	River Flood Watch	BYZ	48 hr
Jun 22, 3:00 PM MDT	River Flood Watch	BYZ	26 hr
Jun 22, 3:37 PM MDT	River Flood Warning	BYZ	18 days
Jun 23, 1:50 PM MDT	River Flood Warning	BYZ	67 hr
Jun 23, 4:50 PM MDT	Mesoscale Discussion	SPC	85 min
Jun 23, 5:07 PM MDT	Special Weather Statement	BYZ	53 min
Jun 24, 5:00 PM MDT	Severe Thunderstorm Warning	BYZ	60 min
Jun 24, 7:41 PM MDT	Severe Thunderstorm Warning	BYZ	45 min
Jun 28, 10:20 AM MDT	River Flood Warning	BYZ	8 days
Jul 3, 12:31 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 3, 4:08 PM MDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 3, 4:32 PM MDT	Special Weather Statement	BYZ	58 min
Jul 3, 5:20 PM MDT	Special Weather Statement	BYZ	55 min
Jul 4, 8:49 PM MDT	Special Weather Statement	BYZ	26 min
Jul 6, 1:12 PM MDT	River Flood Warning	BYZ	47 hr
Jul 6, 2:19 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 6, 4:15 PM MDT	Special Weather Statement	BYZ	60 min
Jul 6, 5:28 PM MDT	Special Weather Statement	BYZ	62 min
Jul 6, 6:04 PM MDT	Special Weather Statement	BYZ	56 min
Jul 6, 6:29 PM MDT	Severe Thunderstorm Warning	BYZ	26 min
Jul 7, 2:29 PM MDT	Special Weather Statement	BYZ	61 min
Jul 7, 5:47 PM MDT	Severe Thunderstorm Warning	BYZ	58 min
Jul 7, 6:40 PM MDT	Special Weather Statement	BYZ	65 min
Jul 8, 1:38 PM MDT	Mesoscale Discussion	SPC	97 min
Jul 8, 2:45 PM MDT	Special Weather Statement	BYZ	60 min
Jul 11, 1:17 PM MDT	Special Weather Statement	BYZ	43 min
Jul 11, 2:53 PM MDT	Mesoscale Discussion	SPC	97 min
Jul 12, 12:56 PM MDT	Mesoscale Discussion	SPC	64 min
Jul 12, 1:38 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 12, 1:48 PM MDT	Special Weather Statement	BYZ	57 min
Jul 12, 5:30 PM MDT	Mesoscale Discussion	SPC	60 min
Jul 13, 3:20 PM MDT	Special Weather Statement	BYZ	40 min
Jul 13, 3:41 PM MDT	Special Weather Statement	BYZ	64 min
Jul 13, 3:45 PM MDT	Severe Thunderstorm Warning	BYZ	17 min
Jul 13, 5:13 PM MDT	Mesoscale Discussion	SPC	62 min
Jul 14, 11:04 AM MDT	Mesoscale Discussion	SPC	116 min
Jul 14, 1:56 PM MDT	Severe Thunderstorm Watch	SPC	9 hr
Jul 15, 2:39 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 22, 3:58 PM MDT	Special Weather Statement	BYZ	62 min
Jul 25, 2:55 PM MDT	Special Weather Statement	BYZ	65 min
Aug 1, 8:07 PM MDT	Special Weather Statement	BYZ	53 min
Aug 1, 9:06 PM MDT	Special Weather Statement	BYZ	54 min
Aug 9, 2:52 PM MDT	Special Weather Statement	BYZ	53 min
Aug 11, 1:00 PM MDT	Special Weather Statement	BYZ	60 min
Aug 15, 1:38 PM MDT	Mesoscale Discussion	SPC	2 hr
Aug 21, 3:32 PM MDT	Special Weather Statement	BYZ	58 min
Aug 21, 4:28 PM MDT	Special Weather Statement	BYZ	62 min
Aug 22, 2:39 PM MDT	Red Flag Warning	BYZ	30 hr
Aug 24, 2:32 PM MDT	Fire Weather Watch	BYZ	13 hr
Aug 25, 3:04 AM MDT	Red Flag Warning	BYZ	18 hr
Aug 26, 3:54 PM MDT	Mesoscale Discussion	SPC	96 min
Aug 26, 4:26 PM MDT	Severe Thunderstorm Watch	SPC	5 hr
Aug 30, 3:26 PM MDT	Red Flag Warning	BYZ	30 hr
Aug 31, 1:55 PM MDT	Special Weather Statement	BYZ	35 min
Aug 31, 2:20 PM MDT	Mesoscale Discussion	SPC	115 min
Sep 19, 2:23 AM MDT	Red Flag Warning	BYZ	19 hr
Sep 19, 7:19 PM MDT	Special Weather Statement	BYZ	56 min
Sep 19, 7:42 PM MDT	Special Weather Statement	BYZ	33 min
Sep 25, 2:45 AM MDT	Red Flag Warning	BYZ	19 hr
Sep 27, 3:18 AM MDT	Red Flag Warning	BYZ	18 hr
Sep 29, 3:05 PM MDT	Fire Weather Watch	BYZ	14 hr
Sep 29, 3:05 PM MDT	Red Flag Warning	BYZ	30 hr
Sep 30, 4:04 AM MDT	Red Flag Warning	BYZ	41 hr
Oct 2, 3:29 AM MDT	Red Flag Warning	BYZ	18 hr
Oct 28, 9:15 PM MDT	Wind Advisory	BYZ	13 hr
Oct 31, 3:56 AM MDT	Winter Weather Advisory	BYZ	38 hr
Nov 2, 1:29 PM MDT	Wind Advisory	BYZ	26 hr
Nov 8, 8:52 PM MST	High Wind Watch	BYZ	18 hr
Nov 9, 3:14 PM MST	Wind Advisory	BYZ	66 hr
Nov 12, 3:46 PM MST	Wind Advisory	BYZ	50 hr
Nov 15, 2:00 AM MST	Winter Weather Advisory	BYZ	7 hr
Nov 15, 3:51 PM MST	High Wind Watch	BYZ	12 hr
Nov 16, 3:43 AM MST	High Wind Warning	BYZ	37 hr
Nov 16, 3:05 PM MST	Winter Storm Watch	BYZ	38 hr
Nov 17, 3:46 AM MST	Winter Storm Warning	BYZ	49 hr
Nov 17, 3:37 PM MST	Winter Weather Advisory	BYZ	48 hr
Nov 21, 3:46 PM MST	Wind Advisory	BYZ	54 hr
Nov 26, 3:19 AM MST	Wind Advisory	BYZ	51 hr
Nov 29, 3:50 AM MST	Winter Storm Watch	BYZ	24 hr
Nov 29, 4:16 PM MST	Winter Weather Advisory	BYZ	35 hr
Nov 30, 4:19 AM MST	Winter Storm Warning	BYZ	26 hr
Dec 1, 3:09 AM MST	Wind Advisory	BYZ	18 hr
Dec 3, 9:39 PM MST	Winter Weather Advisory	BYZ	15 hr
Dec 6, 2:08 AM MST	Wind Advisory	BYZ	13 hr
Dec 19, 2:14 PM MST	Winter Storm Watch	BYZ	26 hr
Dec 20, 3:47 PM MST	Winter Storm Warning	BYZ	29 hr
Dec 22, 3:17 AM MST	High Wind Watch	BYZ	12 hr
Dec 22, 3:16 PM MST	Wind Advisory	BYZ	42 hr
Dec 25, 4:46 PM MST	Wind Advisory	BYZ	17 hr
Dec 26, 2:56 PM MST	Wind Advisory	BYZ	18 hr
Dec 27, 8:56 AM MST	High Wind Warning	BYZ	60 hr
Dec 29, 3:13 PM MST	Wind Advisory	BYZ	30 hr
Dec 30, 3:36 AM MST	Winter Storm Warning	BYZ	30 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	11
Severe Thunderstorm Watch	4
Tornado Watch	1
Mesoscale Discussion	16
Special Weather Statement	27
Flooding
Areal Flood Warning	4
Flash Flood Warning	1
River Flood Warning	4
Flood Watch	4
River Flood Watch	4
Winter
Blizzard Warning	1
Winter Storm Warning	17
Blizzard Watch	1
Winter Storm Watch	11
Winter Weather Advisory	14
Cold
Wind Chill Advisory	4
Wind and dust
High Wind Warning	5
High Wind Watch	6
Wind Advisory	24
Fire
Red Flag Warning	9
Fire Weather Watch	2

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.