Alert archive / North Dakota / Mercer County

Weather alerts in Mercer County, North Dakota, 2018

167 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Mercer County and its neighbors

Each county as a circle sized by its count in 2018. Tap one for its archive.

Alerts: 167
Warnings: 49
Watches: 18
Advisories: 50
Busiest month: June51 alerts
Busiest day: June 1, 201811 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 8 tornado warnings covering Mercer County in 2018 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 31 minutes after it went out.

Mercer County, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
Tornado warnings	8	2	75%	1	100%	31 min
Severe thunderstorm warnings	28	14	50%	9	89%	42 min
Flash flood warnings	1	1	0%	1	100%	183 min

Each office's whole area, 2018

	Warnings	With a report	False alarm ratio	Reports	Inside a warning	Mean lead time
NWS Bismarck, ND: tornado warnings	24	5	79%	22	64%	9 min
NWS Bismarck, ND: severe thunderstorm warnings	275	164	40%	315	90%	28 min
NWS Bismarck, ND: flash flood warnings	7	4	43%	7	71%	119 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, 11:59 AM CST	Wind Chill Advisory	BIS	22 hr
Jan 9, 4:10 AM CST	Winter Weather Advisory	BIS	53 hr
Jan 11, 12:01 AM CST	Wind Chill Advisory	BIS	60 hr
Jan 14, 2:42 AM CST	Wind Chill Advisory	BIS	57 hr
Jan 14, 3:26 PM CST	Wind Chill Warning	BIS	44 hr
Jan 21, 1:46 PM CST	Dense Fog Advisory	BIS	22 hr
Jan 22, 3:08 PM CST	Dense Fog Advisory	BIS	20 hr
Jan 23, 9:11 PM CST	Dense Fog Advisory	BIS	12 hr
Jan 29, 2:26 PM CST	Wind Advisory	BIS	29 hr
Jan 31, 2:34 PM CST	Wind Chill Advisory	BIS	21 hr
Feb 3, 3:18 AM CST	Wind Chill Advisory	BIS	33 hr
Feb 4, 3:03 PM CST	Wind Chill Advisory	BIS	20 hr
Feb 5, 3:52 AM CST	Wind Chill Advisory	BIS	29 hr
Feb 6, 2:05 PM CST	Wind Chill Advisory	BIS	19 hr
Feb 8, 2:45 PM CST	Wind Chill Advisory	BIS	21 hr
Feb 9, 2:59 PM CST	Wind Chill Advisory	BIS	21 hr
Feb 11, 3:43 PM CST	Wind Chill Advisory	BIS	20 hr
Feb 17, 2:39 PM CST	Winter Weather Advisory	BIS	21 hr
Feb 20, 3:07 PM CST	Wind Chill Advisory	BIS	19 hr
Mar 2, 4:22 AM CST	Winter Storm Watch	BIS	59 hr
Mar 3, 3:41 PM CST	Dense Fog Advisory	BIS	20 hr
Mar 3, 4:07 PM CST	Winter Storm Warning	BIS	65 hr
Mar 18, 3:37 AM CDT	Winter Weather Advisory	BIS	33 hr
Mar 22, 12:23 AM CDT	Dense Fog Advisory	BIS	14 hr
Mar 22, 3:51 AM CDT	Winter Storm Warning	BIS	43 hr
Mar 22, 3:51 AM CDT	Winter Weather Advisory	BIS	55 hr
Mar 29, 4:08 AM CDT	Winter Storm Watch	BIS	24 hr
Mar 29, 8:06 PM CDT	Winter Weather Advisory	BIS	8 hr
Mar 30, 4:01 AM CDT	Winter Weather Advisory	BIS	24 hr
Apr 6, 3:18 PM CDT	Winter Weather Advisory	BIS	52 hr
Apr 12, 12:55 AM CDT	Dense Fog Advisory	BIS	10 hr
Apr 19, 6:46 AM CDT	Dense Fog Advisory	BIS	4 hr
Apr 28, 3:40 AM CDT	Red Flag Warning	BIS	17 hr
Apr 29, 10:57 PM CDT	Special Weather Statement	BIS	48 min
May 4, 4:01 AM CDT	Red Flag Warning	BIS	15 hr
May 18, 2:29 PM CDT	Frost Advisory	BIS	19 hr
May 19, 3:48 PM CDT	Frost Advisory	BIS	17 hr
May 22, 7:49 PM CDT	Special Weather Statement	BIS	41 min
May 27, 1:29 AM CDT	Mesoscale Discussion	SPC	3 hr
May 27, 2:49 AM CDT	Special Weather Statement	BIS	41 min
May 27, 3:28 AM CDT	Severe Thunderstorm Warning	BIS	62 min
May 28, 8:01 PM CDT	Severe Thunderstorm Warning	BIS	37 min
May 31, 2:34 AM CDT	Dense Fog Advisory	BIS	8 hr
May 31, 2:47 PM CDT	Mesoscale Discussion	SPC	118 min
May 31, 3:13 PM CDT	Tornado Warning	BIS	32 min
May 31, 3:17 PM CDT	Severe Thunderstorm Watch	SPC	7 hr
May 31, 3:47 PM CDT	Tornado Warning	BIS	28 min
May 31, 4:17 PM CDT	Severe Thunderstorm Warning	BIS	58 min
May 31, 5:29 PM CDT	Severe Thunderstorm Warning	BIS	46 min
May 31, 5:41 PM CDT	Tornado Warning	BIS	34 min
Jun 1, 2:03 AM CDT	Special Weather Statement	BIS	42 min
Jun 1, 6:32 AM CDT	Special Weather Statement	BIS	43 min
Jun 1, 6:56 AM CDT	Severe Thunderstorm Warning	BIS	64 min
Jun 1, 2:13 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 1, 3:30 PM CDT	Tornado Watch	SPC	6 hr
Jun 1, 5:48 PM CDT	Severe Thunderstorm Warning	BIS	57 min
Jun 1, 5:54 PM CDT	Tornado Warning	BIS	36 min
Jun 1, 6:02 PM CDT	Tornado Warning	BIS	28 min
Jun 1, 6:02 PM CDT	Mesoscale Discussion	SPC	88 min
Jun 1, 6:30 PM CDT	Severe Thunderstorm Warning	BIS	60 min
Jun 1, 6:30 PM CDT	Tornado Warning Tornado observed	BIS	30 min
Jun 1, 7:11 PM CDT	Severe Thunderstorm Warning	BIS	41 min
Jun 2, 3:10 AM CDT	Wind Advisory	BIS	18 hr
Jun 7, 10:04 PM CDT	Mesoscale Discussion	SPC	86 min
Jun 10, 2:15 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 10, 3:37 PM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jun 10, 6:15 PM CDT	Mesoscale Discussion	SPC	2 hr
Jun 10, 8:21 PM CDT	Severe Thunderstorm Warning	BIS	54 min
Jun 10, 9:02 PM CDT	Mesoscale Discussion	SPC	118 min
Jun 13, 8:38 PM CDT	Special Weather Statement	BIS	22 min
Jun 13, 9:23 PM CDT	Special Weather Statement	BIS	22 min
Jun 14, 3:40 PM CDT	Tornado Watch	SPC	7 hr
Jun 14, 6:41 PM CDT	Mesoscale Discussion	SPC	94 min
Jun 14, 8:27 PM CDT	Severe Thunderstorm Warning	BIS	63 min
Jun 14, 9:34 PM CDT	Severe Thunderstorm Warning	BIS	18 min
Jun 26, 3:35 PM CDT	Mesoscale Discussion	SPC	85 min
Jun 26, 4:00 PM CDT	Severe Thunderstorm Watch	SPC	9 hr
Jun 26, 6:12 PM CDT	Special Weather Statement	BIS	33 min
Jun 26, 6:24 PM CDT	Severe Thunderstorm Warning	BIS	29 min
Jun 26, 6:46 PM CDT	Mesoscale Discussion	SPC	59 min
Jun 26, 8:17 PM CDT	Severe Thunderstorm Warning	BIS	58 min
Jun 26, 8:44 PM CDT	Severe Thunderstorm Warning	BIS	40 min
Jun 26, 9:05 PM CDT	Mesoscale Discussion	SPC	115 min
Jun 26, 9:55 PM CDT	Severe Thunderstorm Warning	BIS	54 min
Jun 28, 3:17 AM CDT	Special Weather Statement	BIS	28 min
Jun 28, 7:40 AM CDT	Mesoscale Discussion	SPC	3 hr
Jun 28, 1:06 PM CDT	Mesoscale Discussion	SPC	114 min
Jun 28, 2:01 PM CDT	Flash Flood Watch	BIS	14 hr
Jun 28, 3:16 PM CDT	Tornado Watch	SPC	8 hr
Jun 28, 6:59 PM CDT	Mesoscale Discussion	SPC	91 min
Jun 28, 9:06 PM CDT	Mesoscale Discussion	SPC	84 min
Jun 28, 9:11 PM CDT	Flash Flood Warning	BIS	6 hr
Jun 28, 10:07 PM CDT	Severe Thunderstorm Warning	BIS	53 min
Jun 28, 10:21 PM CDT	Mesoscale Discussion	SPC	84 min
Jun 28, 10:46 PM CDT	Severe Thunderstorm Warning	BIS	59 min
Jun 28, 10:54 PM CDT	Severe Thunderstorm Watch	SPC	9 hr
Jun 28, 11:38 PM CDT	Severe Thunderstorm Warning	BIS	67 min
Jun 29, 12:39 AM CDT	Severe Thunderstorm Warning	BIS	66 min
Jun 29, 2:02 AM CDT	Mesoscale Discussion	SPC	118 min
Jun 29, 3:38 AM CDT	High Wind Warning	BIS	2 hr
Jun 29, 11:43 AM CDT	River Flood Warning	BIS	24 hr
Jul 1, 5:40 PM CDT	Mesoscale Discussion	SPC	3 hr
Jul 3, 1:59 AM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 3, 4:15 AM CDT	Mesoscale Discussion	SPC	90 min
Jul 3, 9:39 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 3, 11:32 PM CDT	Areal Flood Advisory	BIS	6 hr
Jul 4, 12:49 AM CDT	Mesoscale Discussion	SPC	116 min
Jul 6, 2:38 PM CDT	Heat Advisory	BIS	29 hr
Jul 7, 9:41 PM CDT	Severe Thunderstorm Watch	SPC	7 hr
Jul 8, 1:17 AM CDT	Severe Thunderstorm Warning	BIS	38 min
Jul 9, 5:48 PM CDT	Mesoscale Discussion	SPC	117 min
Jul 9, 7:01 PM CDT	Severe Thunderstorm Watch	SPC	8 hr
Jul 9, 8:59 PM CDT	Mesoscale Discussion	SPC	91 min
Jul 9, 10:24 PM CDT	Mesoscale Discussion	SPC	96 min
Jul 10, 2:18 AM CDT	Severe Thunderstorm Warning	BIS	57 min
Jul 10, 2:46 AM CDT	Severe Thunderstorm Warning	BIS	59 min
Jul 10, 7:32 PM CDT	Mesoscale Discussion	SPC	118 min
Jul 14, 3:18 PM CDT	Mesoscale Discussion	SPC	117 min
Jul 14, 3:34 PM CDT	Special Weather Statement	BIS	26 min
Jul 14, 3:51 PM CDT	Severe Thunderstorm Warning	BIS	54 min
Jul 14, 4:09 PM CDT	Tornado Warning Tornado observed	BIS	36 min
Jul 14, 4:14 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Jul 14, 4:29 PM CDT	Tornado Warning Tornado observed	BIS	31 min
Jul 14, 4:43 PM CDT	Severe Thunderstorm Warning	BIS	18 min
Jul 14, 4:59 PM CDT	Severe Thunderstorm Warning	BIS	50 min
Jul 19, 3:43 PM CDT	Mesoscale Discussion	SPC	2 hr
Jul 21, 9:40 PM CDT	Mesoscale Discussion	SPC	65 min
Jul 24, 11:28 PM CDT	Mesoscale Discussion	SPC	2 hr
Aug 4, 3:42 PM CDT	Mesoscale Discussion	SPC	93 min
Aug 10, 3:26 PM CDT	Fire Weather Watch	BIS	23 hr
Aug 11, 2:18 PM CDT	Red Flag Warning	BIS	31 hr
Aug 12, 3:13 AM CDT	Heat Advisory	BIS	16 hr
Aug 23, 4:26 PM CDT	Special Weather Statement	BIS	49 min
Sep 3, 5:00 PM CDT	Mesoscale Discussion	SPC	90 min
Sep 3, 5:44 PM CDT	Severe Thunderstorm Watch	SPC	6 hr
Sep 3, 8:14 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 3, 10:40 PM CDT	Mesoscale Discussion	SPC	95 min
Sep 6, 6:06 PM CDT	Mesoscale Discussion	SPC	114 min
Sep 6, 6:29 PM CDT	Severe Thunderstorm Warning	BIS	61 min
Sep 6, 7:18 PM CDT	Special Weather Statement	BIS	42 min
Sep 12, 9:21 PM CDT	Mesoscale Discussion	SPC	2 hr
Sep 12, 10:46 PM CDT	Special Weather Statement	BIS	44 min
Sep 12, 11:09 PM CDT	Severe Thunderstorm Warning	BIS	30 min
Sep 12, 11:15 PM CDT	Severe Thunderstorm Warning	BIS	60 min
Sep 13, 12:24 AM CDT	Special Weather Statement	BIS	51 min
Sep 23, 5:00 AM CDT	Dense Fog Advisory	BIS	7 hr
Sep 25, 2:06 PM CDT	Frost Advisory	BIS	18 hr
Sep 27, 2:55 AM CDT	Freeze Watch	BIS	12 hr
Sep 27, 2:31 PM CDT	Freeze Warning	BIS	19 hr
Sep 28, 3:09 PM CDT	Freeze Warning	BIS	18 hr
Oct 4, 3:20 AM CDT	Winter Weather Advisory	BIS	39 hr
Oct 27, 3:49 AM CDT	Wind Advisory	BIS	16 hr
Nov 1, 3:10 PM CDT	Winter Weather Advisory	BIS	42 hr
Nov 5, 9:17 PM CST	Wind Advisory	BIS	21 hr
Nov 15, 3:01 PM CST	Winter Weather Advisory	BIS	29 hr
Nov 16, 3:03 AM CST	Winter Storm Warning	BIS	17 hr
Nov 20, 8:52 PM CST	Dense Fog Advisory	BIS	14 hr
Nov 21, 2:04 PM CST	Dense Fog Advisory	BIS	22 hr
Nov 27, 3:13 AM CST	Winter Weather Advisory	BIS	45 hr
Nov 27, 8:03 PM CST	Mesoscale Discussion	SPC	6 hr
Nov 29, 3:36 AM CST	Dense Fog Advisory	BIS	9 hr
Nov 29, 6:31 PM CST	Dense Fog Advisory	BIS	20 hr
Nov 30, 4:07 AM CST	Winter Weather Advisory	BIS	38 hr
Dec 1, 2:59 PM CST	Dense Fog Advisory	BIS	19 hr
Dec 25, 4:04 AM CST	Winter Weather Advisory	BIS	55 hr
Dec 25, 2:38 PM CST	Winter Storm Warning	BIS	51 hr
Dec 30, 2:58 PM CST	Wind Chill Advisory	BIS	43 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	28
Tornado Warning	8
Severe Thunderstorm Watch	10
Tornado Watch	3
Mesoscale Discussion	36
Special Weather Statement	14
Flooding
Flash Flood Warning	1
River Flood Warning	1
Flash Flood Watch	1
Areal Flood Advisory	1
Winter
Winter Storm Warning	4
Winter Storm Watch	2
Winter Weather Advisory	13
Heat
Heat Advisory	2
Cold
Freeze Warning	2
Wind Chill Warning	1
Freeze Watch	1
Frost Advisory	3
Wind Chill Advisory	13
Wind and dust
High Wind Warning	1
Wind Advisory	4
Fire
Red Flag Warning	3
Fire Weather Watch	1
Fog and smoke
Dense Fog Advisory	14

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record Forecast The radar archive 2017 2019

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.