Alert archive / North Dakota / Williams County

Weather alerts in Williams County, North Dakota, 2017

91 weather alerts in 2017, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Williams County and its neighbors

Each county as a circle sized by its count in 2017. Tap one for its archive.

Alerts: 91
Warnings: 19
Watches: 5
Advisories: 46
Busiest month: July16 alerts
Busiest day: August 18, 20175 alerts

Over time

By month

Warning verification

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

Williams County, 2017

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	0			0
Severe thunderstorm warnings	4	3	25%	3	100%	4 min
Flash flood warnings	0			0

Each office's whole area, 2017

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Bismarck, ND: tornado warnings	5	1	80%	1	100%	2 min
NWS Bismarck, ND: severe thunderstorm warnings	148	98	34%	188	89%	25 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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

Issued	Product	Office	Lasted
Jan 1, 4:21 AM CST	Winter Weather Advisory	BIS	38 hr
Jan 2, 4:52 PM CST	Wind Chill Advisory	BIS	22 hr
Jan 3, 3:06 PM CST	Wind Chill Warning	BIS	21 hr
Jan 4, 12:07 PM CST	Wind Chill Advisory	BIS	46 hr
Jan 6, 3:23 PM CST	Wind Chill Advisory	BIS	21 hr
Jan 7, 3:37 PM CST	Wind Chill Advisory	BIS	17 hr
Jan 8, 3:51 PM CST	Wind Chill Advisory	BIS	11 hr
Jan 10, 4:03 AM CST	Wind Chill Advisory	BIS	3 days
Jan 10, 2:46 PM CST	Wind Chill Advisory	BIS	65 hr
Jan 11, 2:24 PM CST	Winter Weather Advisory	BIS	24 hr
Jan 20, 5:59 PM CST	Dense Fog Advisory	BIS	18 hr
Jan 29, 3:07 AM CST	High Wind Watch	BIS	266 days
Jan 29, 11:24 PM CST	High Wind Warning	BIS	15 hr
Feb 5, 3:46 AM CST	Winter Weather Advisory	BIS	53 hr
Feb 7, 3:19 PM CST	Wind Chill Advisory	BIS	42 hr
Feb 7, 10:59 PM CST	Wind Chill Warning	BIS	12 hr
Feb 8, 1:08 PM CST	Wind Chill Advisory	BIS	20 hr
Feb 19, 6:10 PM CST	Dense Fog Advisory	BIS	13 hr
Mar 5, 3:54 PM CST	Winter Weather Advisory	BIS	65 hr
Mar 6, 4:52 AM CST	Blizzard Warning	BIS	40 hr
Mar 6, 4:52 AM CST	Winter Storm Warning	BIS	13 hr
Mar 9, 3:39 AM CST	Wind Chill Advisory	BIS	32 hr
Mar 10, 4:14 AM CST	Winter Weather Advisory	BIS	29 hr
Mar 11, 3:55 PM CST	Winter Weather Advisory	BIS	30 hr
Mar 19, 4:16 PM CDT	River Flood Warning	BIS	39 hr
Mar 29, 4:18 AM CDT	Dense Fog Advisory	BIS	6 hr
Apr 12, 3:09 PM CDT	Wind Advisory	BIS	34 hr
Apr 23, 9:58 PM CDT	Winter Weather Advisory	BIS	14 hr
May 15, 6:37 PM CDT	Special Weather Statement	BIS	23 min
May 16, 11:36 PM CDT	River Flood Warning	BIS	62 hr
May 17, 2:38 PM CDT	Frost Advisory	BIS	18 hr
May 18, 2:44 PM CDT	Frost Advisory	BIS	18 hr
May 19, 2:59 PM CDT	Frost Advisory	BIS	12 hr
May 22, 9:24 PM CDT	Frost Advisory	BIS	11 hr
May 24, 11:49 AM CDT	Wind Advisory	BIS	8 hr
May 29, 12:47 PM CDT	Frost Advisory	BIS	20 hr
Jun 4, 1:26 PM CDT	River Flood Warning	BIS	24 days
Jun 22, 3:59 AM CDT	Wind Advisory	BIS	18 hr
Jul 10, 5:47 PM CDT	Mesoscale Discussion	SPC	88 min
Jul 11, 2:10 PM CDT	Special Weather Statement	BIS	50 min
Jul 11, 2:59 PM CDT	Severe Thunderstorm Warning	BIS	61 min
Jul 14, 4:01 AM CDT	Heat Advisory	BIS	16 hr
Jul 14, 3:03 PM CDT	Mesoscale Discussion	SPC	57 min
Jul 16, 7:30 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 19, 7:01 AM CDT	Mesoscale Discussion	SPC	119 min
Jul 20, 1:47 PM CDT	Special Weather Statement	BIS	43 min
Jul 20, 3:32 PM CDT	Mesoscale Discussion	SPC	58 min
Jul 20, 3:50 PM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 20, 5:45 PM CDT	Mesoscale Discussion	SPC	90 min
Jul 27, 7:49 AM CDT	Special Weather Statement	BIS	41 min
Jul 27, 8:38 AM CDT	Special Weather Statement	BIS	37 min
Jul 29, 2:01 PM CDT	Mesoscale Discussion	SPC	89 min
Jul 29, 5:09 PM CDT	Special Weather Statement	BIS	21 min
Jul 29, 7:11 PM CDT	Severe Thunderstorm Warning	BIS	41 min
Aug 10, 6:12 AM CDT	Dense Fog Advisory	BIS	4 hr
Aug 17, 6:59 PM CDT	Special Weather Statement	BIS	46 min
Aug 17, 7:56 PM CDT	Special Weather Statement	BIS	34 min
Aug 17, 8:17 PM CDT	Severe Thunderstorm Warning	BIS	58 min
Aug 17, 9:10 PM CDT	Severe Thunderstorm Warning	BIS	43 min
Aug 17, 9:22 PM CDT	Special Weather Statement	BIS	23 min
Aug 17, 9:47 PM CDT	Special Weather Statement	BIS	43 min
Aug 31, 6:52 PM CDT	Special Weather Statement	BIS	38 min
Aug 31, 8:18 PM CDT	Special Weather Statement	BIS	42 min
Aug 31, 8:21 PM CDT	Special Weather Statement	BIS	39 min
Aug 31, 8:51 PM CDT	Special Weather Statement	BIS	24 min
Sep 3, 3:21 PM CDT	Fire Weather Watch	BIS	12 hr
Sep 4, 3:45 AM CDT	Red Flag Warning	BIS	16 hr
Sep 16, 3:23 PM CDT	Frost Advisory	BIS	18 hr
Oct 6, 2:31 PM CDT	Wind Advisory	BIS	26 hr
Oct 8, 2:48 PM CDT	Freeze Warning	BIS	18 hr
Oct 9, 9:45 AM CDT	Freeze Warning	BIS	23 hr
Oct 17, 1:36 PM CDT	Wind Advisory	BIS	29 hr
Oct 17, 1:49 PM CDT	Fire Weather Watch	BIS	13 hr
Oct 18, 3:16 AM CDT	Red Flag Warning	BIS	16 hr
Oct 22, 4:00 PM CDT	Wind Advisory	BIS	27 hr
Oct 25, 3:36 PM CDT	Wind Advisory	BIS	27 hr
Oct 29, 2:58 AM CDT	Wind Advisory	BIS	38 hr
Nov 2, 2:35 PM CDT	Winter Weather Advisory	BIS	47 hr
Nov 12, 8:53 AM CST	Dense Fog Advisory	BIS	3 hr
Nov 12, 4:24 PM CST	Dense Fog Advisory	BIS	19 hr
Nov 20, 11:40 AM CST	Wind Advisory	BIS	15 hr
Nov 23, 2:39 PM CST	Wind Advisory	BIS	19 hr
Dec 5, 3:34 AM CST	Winter Weather Advisory	BIS	16 hr
Dec 10, 9:39 PM CST	Wind Advisory	BIS	13 hr
Dec 12, 3:08 PM CST	Wind Advisory	BIS	21 hr
Dec 18, 3:01 PM CST	Winter Storm Watch	BIS	24 hr
Dec 19, 2:57 PM CST	Winter Storm Warning	BIS	30 hr
Dec 24, 3:57 AM CST	Wind Chill Warning	BIS	57 hr
Dec 26, 12:49 PM CST	Wind Chill Advisory	BIS	23 hr
Dec 27, 3:45 PM CST	Wind Chill Advisory	BIS	50 hr
Dec 29, 5:15 AM CST	Wind Chill Warning	BIS	3 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	4
Severe Thunderstorm Watch	1
Mesoscale Discussion	7
Special Weather Statement	14
Flooding
River Flood Warning	3
Winter
Blizzard Warning	1
Winter Storm Warning	2
Winter Storm Watch	1
Winter Weather Advisory	9
Heat
Heat Advisory	1
Cold
Freeze Warning	2
Wind Chill Warning	4
Frost Advisory	6
Wind Chill Advisory	12
Wind and dust
High Wind Warning	1
High Wind Watch	1
Wind Advisory	12
Fire
Red Flag Warning	2
Fire Weather Watch	2
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 2016 2018

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.