Alert archive / North Dakota / Cass County
Weather alerts in Cass County, North Dakota, 2018
174 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Cass County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 174
- Warnings
- 60
- Watches
- 16
- Advisories
- 54
- Busiest month
- June40 alerts
- Busiest day
- July 3, 201810 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
3 of 5 tornado warnings covering Cass County in 2018 had a tornado report inside them; 5 of 5 tornado reports fell inside a warning, on average 28 minutes after it went out.
Cass County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 5 | 3 | 40% | 5 | 100% | 28 min |
| Severe thunderstorm warnings | 32 | 28 | 13% | 40 | 68% | 18 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Grand Forks, ND: tornado warnings | 26 | 16 | 38% | 36 | 69% | 16 min |
| NWS Grand Forks, ND: severe thunderstorm warnings | 188 | 168 | 11% | 533 | 84% | 26 min |
| NWS Grand Forks, ND: flash flood warnings | 2 | 2 | 0% | 6 | 100% | 90 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, 11:58 AM CST | Wind Chill Advisory | FGF | 22 hr |
| Jan 2, 2:56 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Jan 4, 2:46 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Jan 5, 2:44 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Jan 9, 4:13 AM CST | Winter Storm Watch | FGF | 24 hr |
| Jan 10, 4:05 AM CST | Winter Storm Warning | FGF | 29 hr |
| Jan 10, 4:05 AM CST | Winter Weather Advisory | FGF | 36 hr |
| Jan 10, 3:11 PM CST | Blizzard Warning | FGF | 25 hr |
| Jan 10, 3:11 PM CST | Winter Storm Warning | FGF | 18 hr |
| Jan 11, 8:48 AM CST | Wind Chill Advisory | FGF | 27 hr |
| Jan 12, 11:57 AM CST | Wind Chill Advisory | FGF | 3 hr |
| Jan 12, 3:08 PM CST | Wind Chill Warning | FGF | 20 hr |
| Jan 12, 3:08 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Jan 14, 4:08 AM CST | Wind Chill Advisory | FGF | 15 hr |
| Jan 14, 4:08 AM CST | Winter Weather Advisory | FGF | 14 hr |
| Jan 14, 3:09 PM CST | Wind Chill Warning | FGF | 4 hr |
| Jan 14, 6:54 PM CST | Wind Chill Warning | FGF | 40 hr |
| Jan 14, 6:54 PM CST | Winter Weather Advisory | FGF | 23 hr |
| Jan 24, 9:29 PM CST | Dense Fog Advisory | FGF | 13 hr |
| Jan 30, 3:26 AM CST | Wind Advisory | FGF | 15 hr |
| Jan 31, 2:37 PM CST | Wind Chill Advisory | FGF | 24 hr |
| Feb 1, 3:47 PM CST | Wind Chill Advisory | FGF | 15 hr |
| Feb 3, 3:02 AM CST | Wind Chill Advisory | FGF | 33 hr |
| Feb 4, 2:41 PM CST | Wind Chill Advisory | FGF | 16 hr |
| Feb 5, 3:09 AM CST | Wind Chill Advisory | FGF | 31 hr |
| Feb 6, 3:26 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Feb 7, 2:49 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Feb 8, 2:32 PM CST | Wind Chill Advisory | FGF | 21 hr |
| Feb 9, 2:50 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Feb 11, 3:20 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Feb 17, 3:07 PM CST | Winter Weather Advisory | FGF | 25 hr |
| Feb 19, 3:41 AM CST | Winter Weather Advisory | FGF | 32 hr |
| Feb 21, 3:15 PM CST | Winter Weather Advisory | FGF | 42 hr |
| Feb 28, 4:12 AM CST | Dense Fog Advisory | FGF | 7 hr |
| Mar 3, 4:05 AM CST | Winter Storm Watch | FGF | 35 hr |
| Mar 4, 2:58 PM CST | Winter Storm Warning | FGF | 32 hr |
| Mar 4, 3:11 PM CST | Special Weather Statement | FGF | 64 min |
| Mar 4, 3:56 PM CST | Special Weather Statement | FGF | 64 min |
| Mar 9, 1:42 AM CST | Dense Fog Advisory | FGF | 7 hr |
| Mar 21, 3:18 PM CDT | Winter Storm Watch | FGF | 24 hr |
| Mar 22, 2:55 PM CDT | Winter Storm Warning | FGF | 27 hr |
| Mar 22, 2:55 PM CDT | Winter Weather Advisory | FGF | 44 hr |
| Mar 25, 10:19 AM CDT | Winter Weather Advisory | FGF | 12 hr |
| Mar 26, 3:28 AM CDT | Winter Weather Advisory | FGF | 15 hr |
| Mar 29, 3:54 AM CDT | Winter Storm Watch | FGF | 25 hr |
| Mar 29, 3:53 PM CDT | Winter Weather Advisory | FGF | 15 hr |
| Mar 30, 4:36 AM CDT | Winter Storm Warning | FGF | 26 hr |
| Mar 30, 1:21 PM CDT | Blizzard Warning | FGF | 15 hr |
| Apr 11, 12:10 PM CDT | River Flood Watch | FGF | 46 hr |
| Apr 13, 10:15 AM CDT | River Flood Warning | FGF | 7 days |
| Apr 17, 11:43 AM CDT | River Flood Watch | FGF | 4 days |
| Apr 18, 11:35 AM CDT | River Flood Warning | FGF | 7 days |
| Apr 20, 10:49 AM CDT | River Flood Warning | FGF | 4 days |
| Apr 21, 9:14 PM CDT | River Flood Warning | FGF | 5 days |
| Apr 29, 4:06 AM CDT | Wind Advisory | FGF | 16 hr |
| May 4, 4:04 AM CDT | Red Flag Warning | FGF | 15 hr |
| May 7, 4:05 AM CDT | Red Flag Warning | FGF | 14 hr |
| May 27, 7:22 AM CDT | Special Weather Statement | FGF | 38 min |
| May 27, 7:59 AM CDT | Special Weather Statement | FGF | 46 min |
| May 27, 12:52 PM CDT | Special Weather Statement | FGF | 23 min |
| Jun 5, 6:01 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 5, 9:07 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 5, 11:22 PM CDT | Severe Thunderstorm Warning | FGF | 38 min |
| Jun 5, 11:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Jun 5, 11:40 PM CDT | Severe Thunderstorm Warning | FGF | 65 min |
| Jun 5, 11:56 PM CDT | Severe Thunderstorm Warning | FGF | 64 min |
| Jun 6, 12:21 AM CDT | Severe Thunderstorm Warning | FGF | 39 min |
| Jun 8, 1:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Jun 8, 3:09 PM CDT | Tornado Warning | FGF | 36 min |
| Jun 8, 3:36 PM CDT | Tornado Warning | FGF | 39 min |
| Jun 8, 4:14 PM CDT | Tornado Warning | FGF | 46 min |
| Jun 8, 4:54 PM CDT | Tornado Warning | FGF | 51 min |
| Jun 8, 5:37 PM CDT | Tornado Warning | FGF | 38 min |
| Jun 9, 6:37 PM CDT | Severe Thunderstorm Warning | FGF | 23 min |
| Jun 9, 6:59 PM CDT | Severe Thunderstorm Warning | FGF | 31 min |
| Jun 12, 4:57 AM CDT | Dense Fog Advisory | FGF | 4 hr |
| Jun 15, 12:17 AM CDT | Severe Thunderstorm Warning | FGF | 28 min |
| Jun 15, 12:44 AM CDT | Special Weather Statement | FGF | 31 min |
| Jun 15, 1:01 AM CDT | Severe Thunderstorm Warning | FGF | 44 min |
| Jun 15, 1:17 AM CDT | Special Weather Statement | FGF | 43 min |
| Jun 15, 1:33 AM CDT | Mesoscale Discussion | SPC | 87 min |
| Jun 15, 1:55 AM CDT | Severe Thunderstorm Warning | FGF | 34 min |
| Jun 16, 7:44 AM CDT | Severe Thunderstorm Warning | FGF | 46 min |
| Jun 16, 8:23 AM CDT | Severe Thunderstorm Warning | FGF | 42 min |
| Jun 16, 3:12 PM CDT | Flash Flood Watch | FGF | 16 hr |
| Jun 16, 6:06 PM CDT | Severe Thunderstorm Warning | FGF | 26 min |
| Jun 17, 10:05 AM CDT | River Flood Watch | FGF | 24 hr |
| Jun 18, 9:53 AM CDT | River Flood Warning | FGF | 34 hr |
| Jun 28, 3:52 AM CDT | Mesoscale Discussion | SPC | 83 min |
| Jun 28, 7:40 AM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jun 28, 1:33 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 28, 3:53 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jun 28, 10:21 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Jun 28, 10:54 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Jun 29, 2:02 AM CDT | Mesoscale Discussion | SPC | 118 min |
| Jun 29, 2:59 AM CDT | Severe Thunderstorm Warning | FGF | 61 min |
| Jun 29, 3:16 AM CDT | Severe Thunderstorm Warning | FGF | 59 min |
| Jun 29, 3:51 AM CDT | Severe Thunderstorm Warning | FGF | 54 min |
| Jun 29, 4:06 AM CDT | Severe Thunderstorm Warning | FGF | 54 min |
| Jun 29, 4:14 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 1, 5:40 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 2, 5:23 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 2, 9:27 PM CDT | Severe Thunderstorm Warning | FGF | 48 min |
| Jul 2, 9:59 PM CDT | Severe Thunderstorm Warning | FGF | 46 min |
| Jul 2, 10:45 PM CDT | Severe Thunderstorm Warning | FGF | 60 min |
| Jul 2, 11:01 PM CDT | Special Weather Statement | FGF | 14 min |
| Jul 2, 11:19 PM CDT | Special Weather Statement | FGF | 41 min |
| Jul 2, 11:32 PM CDT | Mesoscale Discussion | SPC | 88 min |
| 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, 7:01 AM CDT | Mesoscale Discussion | SPC | 119 min |
| Jul 3, 7:25 AM CDT | Special Weather Statement | FGF | 50 min |
| Jul 4, 12:49 AM CDT | Mesoscale Discussion | SPC | 116 min |
| Jul 4, 1:34 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 4, 2:33 AM CDT | Severe Thunderstorm Warning | FGF | 57 min |
| Jul 4, 3:09 AM CDT | Severe Thunderstorm Warning | FGF | 66 min |
| Jul 4, 3:24 AM CDT | Severe Thunderstorm Warning | FGF | 66 min |
| Jul 6, 3:05 PM CDT | Heat Advisory | FGF | 29 hr |
| Jul 8, 2:35 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Jul 8, 1:16 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 8, 3:52 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 8, 5:46 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Jul 8, 6:56 PM CDT | Special Weather Statement | FGF | 34 min |
| Jul 8, 7:10 PM CDT | Severe Thunderstorm Warning | FGF | 16 min |
| Jul 8, 7:37 PM CDT | Severe Thunderstorm Warning | FGF | 23 min |
| Jul 19, 10:14 AM CDT | Areal Flood Advisory | FGF | 6 hr |
| Jul 19, 3:34 PM CDT | Areal Flood Advisory | FGF | 7 hr |
| Jul 19, 5:16 PM CDT | Areal Flood Advisory | FGF | 5 hr |
| Aug 14, 1:30 AM CDT | Special Weather Statement | FGF | 60 min |
| Aug 25, 3:02 AM CDT | Dense Fog Advisory | FGF | 8 hr |
| Aug 25, 10:08 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Aug 26, 1:37 AM CDT | Special Weather Statement | FGF | 53 min |
| Aug 26, 2:05 AM CDT | Severe Thunderstorm Warning | FGF | 25 min |
| Aug 26, 2:30 AM CDT | Severe Thunderstorm Warning | FGF | 30 min |
| Aug 26, 2:46 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 26, 4:20 AM CDT | Special Weather Statement | FGF | 40 min |
| Aug 26, 11:56 AM CDT | Mesoscale Discussion | SPC | 109 min |
| Aug 26, 3:12 PM CDT | Severe Thunderstorm Warning | FGF | 33 min |
| Aug 26, 6:15 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 26, 7:37 PM CDT | Tornado Watch | SPC | 5 hr |
| Aug 26, 9:48 PM CDT | Special Weather Statement | FGF | 42 min |
| Aug 26, 10:30 PM CDT | Special Weather Statement | FGF | 45 min |
| Aug 26, 10:55 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 27, 7:54 PM CDT | Severe Thunderstorm Warning | FGF | 51 min |
| Aug 27, 8:30 PM CDT | Severe Thunderstorm Warning | FGF | 30 min |
| Aug 27, 8:56 PM CDT | Severe Thunderstorm Warning | FGF | 64 min |
| Sep 2, 3:00 AM CDT | Special Weather Statement | FGF | 45 min |
| Sep 14, 7:46 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Sep 14, 8:28 PM CDT | Severe Thunderstorm Warning | FGF | 47 min |
| Sep 14, 9:14 PM CDT | Severe Thunderstorm Warning | FGF | 46 min |
| Sep 14, 10:02 PM CDT | Special Weather Statement | FGF | 28 min |
| Sep 15, 2:35 PM CDT | Wind Advisory | FGF | 26 hr |
| Sep 27, 2:38 PM CDT | Frost Advisory | FGF | 18 hr |
| Sep 28, 3:53 AM CDT | Freeze Warning | FGF | 29 hr |
| Oct 9, 3:11 PM CDT | Winter Weather Advisory | FGF | 37 hr |
| Oct 10, 10:39 AM CDT | Winter Storm Warning | FGF | 11 hr |
| Oct 19, 10:36 PM CDT | Special Weather Statement | FGF | 24 min |
| Oct 25, 9:55 PM CDT | Dense Fog Advisory | FGF | 12 hr |
| Oct 26, 9:37 PM CDT | Dense Fog Advisory | FGF | 14 hr |
| Nov 22, 3:40 PM CST | Dense Fog Advisory | FGF | 18 hr |
| Nov 30, 6:52 PM CST | Dense Fog Advisory | FGF | 20 hr |
| Dec 11, 2:52 PM CST | Winter Weather Advisory | FGF | 9 hr |
| Dec 11, 11:56 PM CST | Dense Fog Advisory | FGF | 11 hr |
| Dec 12, 9:38 PM CST | Winter Weather Advisory | FGF | 11 hr |
| Dec 19, 3:59 AM CST | Winter Weather Advisory | FGF | 8 hr |
| Dec 25, 4:06 AM CST | Winter Storm Watch | FGF | 11 hr |
| Dec 25, 3:11 PM CST | Winter Storm Warning | FGF | 61 hr |
| Dec 27, 4:00 AM CST | Blizzard Warning | FGF | 26 hr |
| Dec 28, 3:50 AM CST | Wind Chill Advisory | FGF | 8 hr |
| Dec 28, 2:43 PM CST | Wind Chill Advisory | FGF | 18 hr |
| Dec 30, 3:01 PM CST | Wind Chill Advisory | FGF | 23 hr |
| Dec 30, 3:01 PM CST | Winter Weather Advisory | FGF | 21 hr |
| Dec 31, 4:27 AM CST | Blizzard Warning | FGF | 14 hr |
| Dec 31, 2:24 PM CST | Wind Chill Warning | FGF | 19 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 | 32 |
| Tornado Warning | 5 |
| Severe Thunderstorm Watch | 6 |
| Tornado Watch | 1 |
| Mesoscale Discussion | 25 |
| Special Weather Statement | 19 |
| Flooding | |
| River Flood Warning | 5 |
| Flash Flood Watch | 1 |
| River Flood Watch | 3 |
| Areal Flood Advisory | 3 |
| Winter | |
| Blizzard Warning | 4 |
| Winter Storm Warning | 7 |
| Winter Storm Watch | 5 |
| Winter Weather Advisory | 15 |
| Heat | |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 1 |
| Wind Chill Warning | 4 |
| Frost Advisory | 1 |
| Wind Chill Advisory | 21 |
| Wind and dust | |
| Wind Advisory | 3 |
| Fire | |
| Red Flag Warning | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 10 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.