Alert archive / Montana / Petroleum County

Weather alerts in Petroleum County, Montana, 2021

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

Petroleum County and its neighbors

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

Alerts: 188
Warnings: 48
Watches: 36
Advisories: 70
Busiest month: June50 alerts
Busiest day: June 10, 202112 alerts

Over time

By month

Warning verification

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

Petroleum County, 2021

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			0
Severe thunderstorm warnings	12	5	58%	4	100%	25 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 Glasgow, MT: tornado warnings	4	0	100%	0
NWS Glasgow, MT: severe thunderstorm warnings	87	53	39%	188	74%	29 min
NWS Glasgow, MT: flash flood warnings	1	1	0%	5	20%	4 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
Jan 1, 2:35 PM MST	High Wind Warning	GGW	55 hr
Jan 8, 6:13 PM MST	Dense Fog Advisory	GGW	19 hr
Jan 9, 5:02 PM MST	Dense Fog Advisory	GGW	15 hr
Jan 11, 3:09 AM MST	High Wind Watch	GGW	33 hr
Jan 12, 12:26 PM MST	High Wind Warning	GGW	55 hr
Feb 4, 2:05 PM MST	Wind Chill Advisory	GGW	6 days
Feb 4, 2:05 PM MST	Winter Storm Watch	GGW	13 hr
Feb 5, 2:48 AM MST	Winter Weather Advisory	GGW	48 hr
Feb 9, 2:35 PM MST	Wind Chill Warning	GGW	5 days
Feb 14, 2:26 PM MST	Wind Chill Advisory	GGW	21 hr
Feb 19, 2:08 PM MST	High Wind Watch	GGW	60 hr
Feb 21, 2:24 AM MST	High Wind Warning	GGW	40 hr
Feb 22, 5:53 PM MST	High Wind Warning	GGW	20 hr
Mar 5, 1:18 PM MST	Fire Weather Watch	GGW	13 hr
Mar 6, 2:24 AM MST	Red Flag Warning	GGW	18 hr
Mar 26, 3:12 AM MDT	Fire Weather Watch	GGW	24 hr
Mar 27, 3:15 AM MDT	Red Flag Warning	GGW	41 hr
Mar 27, 2:16 PM MDT	High Wind Watch	GGW	13 hr
Mar 28, 3:11 AM MDT	High Wind Warning	GGW	45 hr
Mar 30, 2:05 PM MDT	Fire Weather Watch	GGW	25 hr
Mar 31, 2:50 PM MDT	Fire Weather Watch	GGW	12 hr
Mar 31, 2:50 PM MDT	Red Flag Warning	GGW	30 hr
Apr 1, 2:53 AM MDT	Lake Wind Advisory	GGW	17 hr
Apr 7, 2:32 PM MDT	Lake Wind Advisory	GGW	39 hr
Apr 9, 8:09 PM MDT	Lake Wind Advisory	GGW	3 days
Apr 18, 3:27 AM MDT	Lake Wind Advisory	GGW	18 hr
Apr 18, 3:28 AM MDT	Winter Weather Advisory	GGW	24 hr
Apr 21, 2:18 PM MDT	Lake Wind Advisory	GGW	32 hr
Apr 28, 8:46 AM MDT	Lake Wind Advisory	GGW	11 hr
Apr 28, 3:00 PM MDT	Fire Weather Watch	GGW	24 hr
Apr 29, 2:42 PM MDT	Fire Weather Watch	GGW	37 hr
Apr 29, 2:42 PM MDT	Red Flag Warning	GGW	34 hr
Apr 29, 2:51 PM MDT	Lake Wind Advisory	GGW	51 hr
May 1, 3:14 AM MDT	Red Flag Warning	GGW	17 hr
May 1, 2:13 PM MDT	Lake Wind Advisory	GGW	31 hr
May 6, 1:36 PM MDT	Lake Wind Advisory	GGW	61 hr
May 18, 3:08 AM MDT	Lake Wind Advisory	GGW	24 hr
May 19, 2:25 PM MDT	Lake Wind Advisory	GGW	36 hr
May 22, 2:13 PM MDT	Lake Wind Advisory	GGW	31 hr
May 23, 2:14 PM MDT	Lake Wind Advisory	GGW	52 hr
Jun 2, 10:52 AM MDT	Fire Weather Watch	GGW	26 hr
Jun 3, 2:32 AM MDT	Heat Advisory	GGW	18 hr
Jun 3, 1:12 PM MDT	Red Flag Warning	GGW	35 hr
Jun 4, 2:19 AM MDT	Heat Advisory	GGW	18 hr
Jun 4, 4:01 PM MDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 4, 8:10 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 4, 10:03 PM MDT	Special Weather Statement	GGW	42 min
Jun 4, 11:47 PM MDT	Special Weather Statement	GGW	58 min
Jun 5, 2:26 PM MDT	Lake Wind Advisory	GGW	28 hr
Jun 6, 3:01 AM MDT	Red Flag Warning	GGW	17 hr
Jun 7, 3:17 PM MDT	Lake Wind Advisory	GGW	31 hr
Jun 9, 3:44 PM MDT	Lake Wind Advisory	GGW	51 hr
Jun 9, 3:45 PM MDT	Fire Weather Watch	GGW	12 hr
Jun 9, 5:05 PM MDT	Mesoscale Discussion	SPC	85 min
Jun 9, 6:42 PM MDT	Severe Thunderstorm Watch	SPC	5 hr
Jun 9, 8:33 PM MDT	Special Weather Statement	GGW	42 min
Jun 9, 8:34 PM MDT	Mesoscale Discussion	SPC	86 min
Jun 9, 8:45 PM MDT	Special Weather Statement	TFX	30 min
Jun 9, 9:32 PM MDT	Severe Thunderstorm Warning	GGW	58 min
Jun 9, 10:25 PM MDT	Severe Thunderstorm Warning	GGW	65 min
Jun 9, 10:51 PM MDT	Mesoscale Discussion	SPC	84 min
Jun 10, 1:47 PM MDT	Mesoscale Discussion	SPC	88 min
Jun 10, 2:52 PM MDT	Severe Thunderstorm Watch	SPC	6 hr
Jun 10, 3:27 PM MDT	Severe Thunderstorm Warning	GGW	63 min
Jun 10, 4:05 PM MDT	Severe Thunderstorm Warning	GGW	55 min
Jun 10, 4:48 PM MDT	Mesoscale Discussion	SPC	87 min
Jun 13, 1:10 PM MDT	Excessive Heat Watch	GGW	14 hr
Jun 13, 1:10 PM MDT	Heat Advisory	GGW	35 hr
Jun 13, 8:40 PM MDT	Lake Wind Advisory	GGW	45 hr
Jun 14, 3:02 AM MDT	Excessive Heat Warning	GGW	42 hr
Jun 14, 3:10 AM MDT	Fire Weather Watch	GGW	24 hr
Jun 14, 1:45 PM MDT	Red Flag Warning	GGW	56 hr
Jun 14, 2:27 PM MDT	Mesoscale Discussion	SPC	2 hr
Jun 14, 8:19 PM MDT	Special Weather Statement	GGW	41 min
Jun 14, 8:26 PM MDT	Severe Thunderstorm Warning	GGW	64 min
Jun 14, 9:20 PM MDT	Special Weather Statement	GGW	40 min
Jun 14, 9:26 PM MDT	Severe Thunderstorm Warning	GGW	64 min
Jun 15, 3:20 PM MDT	Lake Wind Advisory	GGW	29 hr
Jun 16, 2:20 PM MDT	Red Flag Warning	GGW	31 hr
Jun 18, 3:16 AM MDT	Fire Weather Watch	GGW	11 hr
Jun 18, 2:38 PM MDT	Red Flag Warning	GGW	30 hr
Jun 18, 2:40 PM MDT	Lake Wind Advisory	GGW	30 hr
Jun 24, 6:09 PM MDT	Special Weather Statement	GGW	66 min
Jun 24, 6:22 PM MDT	Severe Thunderstorm Warning	GGW	37 min
Jun 25, 2:27 PM MDT	Lake Wind Advisory	GGW	29 hr
Jun 26, 7:40 PM MDT	Lake Wind Advisory	GGW	25 hr
Jun 29, 2:30 AM MDT	Excessive Heat Watch	GGW	24 hr
Jun 29, 2:17 PM MDT	Fire Weather Watch	GGW	12 hr
Jun 30, 2:13 AM MDT	Excessive Heat Warning	GGW	5 days
Jun 30, 2:29 AM MDT	Red Flag Warning	GGW	67 hr
Jul 1, 3:00 AM MDT	Lake Wind Advisory	GGW	19 hr
Jul 2, 2:59 PM MDT	Red Flag Warning	GGW	30 hr
Jul 6, 2:37 PM MDT	Mesoscale Discussion	SPC	83 min
Jul 6, 6:40 PM MDT	Mesoscale Discussion	SPC	95 min
Jul 6, 7:06 PM MDT	Severe Thunderstorm Warning	GGW	54 min
Jul 7, 2:03 PM MDT	Mesoscale Discussion	SPC	117 min
Jul 7, 3:03 PM MDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 7, 3:58 PM MDT	Special Weather Statement	GGW	47 min
Jul 7, 4:42 PM MDT	Special Weather Statement	GGW	48 min
Jul 7, 5:48 PM MDT	Mesoscale Discussion	SPC	117 min
Jul 7, 6:44 PM MDT	Severe Thunderstorm Warning	GGW	39 min
Jul 7, 6:56 PM MDT	Special Weather Statement	TFX	34 min
Jul 9, 9:48 AM MDT	Excessive Heat Watch	GGW	42 hr
Jul 11, 3:21 AM MDT	Red Flag Warning	GGW	18 hr
Jul 11, 3:23 AM MDT	Heat Advisory	GGW	18 hr
Jul 11, 2:35 PM MDT	Lake Wind Advisory	GGW	9 hr
Jul 14, 1:30 PM MDT	Excessive Heat Watch	GGW	44 hr
Jul 16, 9:12 AM MDT	Excessive Heat Warning	GGW	6 days
Jul 18, 3:26 AM MDT	Fire Weather Watch	GGW	10 hr
Jul 18, 1:52 PM MDT	Red Flag Warning	GGW	33 hr
Jul 21, 3:05 PM MDT	Fire Weather Watch	GGW	23 hr
Jul 21, 6:08 PM MDT	Special Weather Statement	GGW	37 min
Jul 22, 1:50 PM MDT	Mesoscale Discussion	SPC	2 hr
Jul 22, 2:16 PM MDT	Red Flag Warning	GGW	31 hr
Jul 22, 4:07 PM MDT	Severe Thunderstorm Watch	SPC	5 hr
Jul 22, 4:08 PM MDT	Special Weather Statement	GGW	52 min
Jul 22, 4:58 PM MDT	Special Weather Statement	GGW	47 min
Jul 22, 5:17 PM MDT	Severe Thunderstorm Warning	GGW	28 min
Jul 22, 5:43 PM MDT	Special Weather Statement	TFX	17 min
Jul 24, 1:56 PM MDT	Excessive Heat Watch	GGW	23 hr
Jul 25, 1:20 PM MDT	Excessive Heat Warning	GGW	57 hr
Aug 4, 10:48 PM MDT	Special Weather Statement	GGW	57 min
Aug 7, 2:18 PM MDT	Lake Wind Advisory	GGW	37 hr
Aug 9, 2:09 PM MDT	Lake Wind Advisory	GGW	31 hr
Aug 10, 1:50 PM MDT	Fire Weather Watch	GGW	13 hr
Aug 11, 2:28 AM MDT	Lake Wind Advisory	GGW	19 hr
Aug 11, 2:32 AM MDT	Red Flag Warning	GGW	19 hr
Aug 14, 2:37 AM MDT	Fire Weather Watch	GGW	12 hr
Aug 14, 2:12 PM MDT	Red Flag Warning	GGW	4 days
Aug 15, 2:32 PM MDT	Heat Advisory	GGW	54 hr
Aug 16, 2:51 AM MDT	Lake Wind Advisory	GGW	17 hr
Aug 16, 2:49 PM MDT	Mesoscale Discussion	SPC	116 min
Aug 17, 2:57 AM MDT	Lake Wind Advisory	GGW	39 hr
Aug 17, 2:21 PM MDT	Mesoscale Discussion	SPC	114 min
Aug 21, 2:17 PM MDT	Lake Wind Advisory	GGW	29 hr
Aug 23, 3:01 PM MDT	Lake Wind Advisory	GGW	28 hr
Aug 26, 2:06 PM MDT	Mesoscale Discussion	SPC	114 min
Aug 26, 4:45 PM MDT	Special Weather Statement	GGW	45 min
Aug 26, 4:59 PM MDT	Severe Thunderstorm Warning	GGW	61 min
Aug 26, 5:58 PM MDT	Severe Thunderstorm Warning	GGW	62 min
Aug 26, 6:08 PM MDT	Areal Flood Advisory	GGW	2 hr
Aug 26, 6:21 PM MDT	Special Weather Statement	GGW	39 min
Aug 26, 6:54 PM MDT	Areal Flood Advisory	GGW	2 hr
Aug 26, 6:56 PM MDT	Special Weather Statement	GGW	64 min
Sep 1, 1:32 PM MDT	Lake Wind Advisory	GGW	3 hr
Sep 4, 2:33 PM MDT	Fire Weather Watch	GGW	24 hr
Sep 5, 2:30 PM MDT	Red Flag Warning	GGW	30 hr
Sep 5, 2:31 PM MDT	Lake Wind Advisory	GGW	30 hr
Sep 7, 1:20 PM MDT	Fire Weather Watch	GGW	24 hr
Sep 8, 1:38 PM MDT	Red Flag Warning	GGW	30 hr
Sep 13, 2:13 PM MDT	Fire Weather Watch	GGW	23 hr
Sep 14, 1:08 PM MDT	Red Flag Warning	GGW	30 hr
Sep 14, 1:33 PM MDT	Lake Wind Advisory	GGW	30 hr
Sep 16, 2:41 AM MDT	Lake Wind Advisory	GGW	18 hr
Sep 16, 2:32 PM MDT	Red Flag Warning	GGW	55 hr
Sep 17, 2:23 AM MDT	Lake Wind Advisory	GGW	18 hr
Sep 18, 2:35 AM MDT	Lake Wind Advisory	GGW	24 hr
Sep 27, 2:13 PM MDT	Lake Wind Advisory	GGW	46 hr
Sep 28, 3:38 AM MDT	Red Flag Warning	GGW	17 hr
Oct 3, 2:57 AM MDT	Fire Weather Watch	GGW	11 hr
Oct 3, 1:27 PM MDT	Red Flag Warning	GGW	55 hr
Oct 10, 2:52 AM MDT	Lake Wind Advisory	GGW	27 hr
Oct 14, 3:11 AM MDT	Lake Wind Advisory	GGW	15 hr
Oct 22, 3:00 AM MDT	Lake Wind Advisory	GGW	32 hr
Oct 24, 2:51 AM MDT	Lake Wind Advisory	GGW	38 hr
Oct 26, 1:19 PM MDT	Lake Wind Advisory	GGW	38 hr
Oct 29, 8:58 AM MDT	Lake Wind Advisory	GGW	19 hr
Oct 29, 2:38 PM MDT	Lake Wind Advisory	GGW	14 hr
Nov 4, 2:26 PM MDT	Lake Wind Advisory	GGW	13 hr
Nov 4, 2:28 PM MDT	Lake Wind Advisory	GGW	28 hr
Nov 9, 12:47 PM MST	Lake Wind Advisory	GGW	56 hr
Nov 12, 9:03 AM MST	High Wind Watch	GGW	18 hr
Nov 13, 2:45 AM MST	High Wind Warning	GGW	14 hr
Nov 14, 2:53 AM MST	Lake Wind Advisory	GGW	24 hr
Nov 14, 2:33 PM MST	High Wind Watch	GGW	12 hr
Nov 15, 2:33 AM MST	High Wind Warning	GGW	62 hr
Nov 17, 2:44 AM MST	Lake Wind Advisory	GGW	16 hr
Nov 23, 1:37 PM MST	Lake Wind Advisory	GGW	17 hr
Nov 25, 2:31 AM MST	Lake Wind Advisory	GGW	48 hr
Nov 26, 2:30 PM MST	High Wind Watch	GGW	23 hr
Nov 27, 1:05 PM MST	High Wind Warning	GGW	30 hr
Dec 1, 8:42 AM MST	Lake Wind Advisory	GGW	8 hr
Dec 3, 2:56 AM MST	Winter Weather Advisory	GGW	48 hr
Dec 16, 1:31 PM MST	Wind Chill Advisory	GGW	45 hr
Dec 18, 2:42 PM MST	Winter Weather Advisory	GGW	38 hr
Dec 23, 8:14 PM MST	Special Weather Statement	GGW	61 min
Dec 25, 1:02 PM MST	Winter Weather Advisory	GGW	33 hr
Dec 26, 2:13 PM MST	Wind Chill Advisory	GGW	7 days

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	12
Severe Thunderstorm Watch	5
Mesoscale Discussion	15
Special Weather Statement	19
Flooding
Areal Flood Advisory	2
Winter
Winter Storm Watch	1
Winter Weather Advisory	5
Heat
Excessive Heat Warning	4
Excessive Heat Watch	5
Heat Advisory	5
Cold
Wind Chill Warning	1
Wind Chill Advisory	4
Wind and dust
High Wind Warning	8
High Wind Watch	6
Lake Wind Advisory	52
Fire
Red Flag Warning	23
Fire Weather Watch	19
Fog and smoke
Dense Fog Advisory	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 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.