Alert archive / North Dakota / Cass County
Weather alerts in Cass County, North Dakota, 2015
149 weather alerts in 2015, 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 2015. Tap one for its archive.
- Alerts
- 149
- Warnings
- 46
- Watches
- 15
- Advisories
- 49
- Busiest month
- July39 alerts
- Busiest day
- June 27, 20158 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
1 of 6 tornado warnings covering Cass County in 2015 had a tornado report inside them.
Cass County, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 6 | 1 | 83% | 0 | ||
| Severe thunderstorm warnings | 23 | 21 | 9% | 17 | 65% | 27 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2015
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Grand Forks, ND: tornado warnings | 52 | 14 | 73% | 54 | 85% | 22 min |
| NWS Grand Forks, ND: severe thunderstorm warnings | 133 | 103 | 23% | 324 | 69% | 27 min |
| NWS Grand Forks, ND: flash flood warnings | 1 | 1 | 0% | 2 | 100% | 253 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 2, 4:17 AM CST | Winter Weather Advisory | FGF | 35 hr |
| Jan 3, 2:49 PM CST | Wind Chill Warning | FGF | 45 hr |
| Jan 5, 3:13 PM CST | Wind Chill Advisory | FGF | 33 hr |
| Jan 6, 3:41 AM CST | Wind Chill Warning | FGF | 32 hr |
| Jan 8, 3:06 AM CST | Winter Weather Advisory | FGF | 15 hr |
| Jan 8, 3:33 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Jan 9, 3:30 PM CST | Wind Chill Advisory | FGF | 21 hr |
| Jan 11, 2:11 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Jan 12, 3:11 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Jan 17, 1:22 AM CST | Freezing Rain Advisory | FGF | 7 hr |
| Jan 28, 8:03 PM CST | Freezing Rain Advisory | FGF | 7 hr |
| Jan 31, 3:16 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Feb 9, 3:19 PM CST | Winter Weather Advisory | FGF | 37 hr |
| Feb 10, 12:52 PM CST | Winter Weather Advisory | FGF | 15 hr |
| Feb 11, 4:07 AM CST | Wind Chill Advisory | FGF | 32 hr |
| Feb 13, 3:15 PM CST | Wind Chill Advisory | FGF | 23 hr |
| Feb 15, 1:25 AM CST | Winter Weather Advisory | FGF | 8 hr |
| Feb 16, 3:29 PM CST | Wind Chill Advisory | FGF | 45 hr |
| Feb 17, 3:32 AM CST | Wind Chill Advisory | FGF | 55 hr |
| Feb 20, 2:50 PM CST | Wind Chill Advisory | FGF | 30 hr |
| Feb 21, 3:49 AM CST | Wind Chill Warning | FGF | 32 hr |
| Feb 22, 11:40 AM CST | Wind Chill Advisory | FGF | 21 hr |
| Feb 25, 3:12 PM CST | Wind Chill Advisory | FGF | 20 hr |
| Feb 26, 2:38 PM CST | Wind Chill Advisory | FGF | 19 hr |
| Mar 2, 2:32 PM CST | Wind Advisory | FGF | 27 hr |
| Mar 2, 2:34 PM CST | Winter Weather Advisory | FGF | 25 hr |
| Mar 3, 3:28 PM CST | Wind Chill Advisory | FGF | 21 hr |
| Mar 4, 3:34 PM CST | Wind Chill Advisory | FGF | 18 hr |
| Mar 25, 3:36 AM CDT | Wind Advisory | FGF | 14 hr |
| Mar 28, 3:33 PM CDT | Wind Advisory | FGF | 27 hr |
| Apr 2, 4:05 AM CDT | Red Flag Warning | FGF | 15 hr |
| Apr 2, 10:32 AM CDT | Wind Advisory | FGF | 8 hr |
| Apr 11, 3:27 AM CDT | Red Flag Warning | FGF | 17 hr |
| Apr 12, 1:46 PM CDT | Fire Weather Watch | FGF | 14 hr |
| Apr 13, 3:37 AM CDT | Red Flag Warning | FGF | 16 hr |
| Apr 13, 3:06 PM CDT | Fire Weather Watch | FGF | 12 hr |
| Apr 14, 3:31 AM CDT | Fire Weather Watch | FGF | 24 hr |
| Apr 14, 3:31 AM CDT | Red Flag Warning | FGF | 17 hr |
| Apr 15, 3:15 AM CDT | Red Flag Warning | FGF | 17 hr |
| Apr 15, 3:38 AM CDT | Wind Advisory | FGF | 15 hr |
| Apr 15, 3:42 PM CDT | Special Weather Statement | FGF | 48 min |
| Apr 15, 4:44 PM CDT | Special Weather Statement | FGF | 61 min |
| Apr 20, 5:31 AM CDT | Wind Advisory | FGF | 15 hr |
| Apr 21, 11:17 AM CDT | Wind Advisory | FGF | 8 hr |
| Apr 29, 2:59 PM CDT | Red Flag Warning | FGF | 28 hr |
| May 1, 3:10 PM CDT | Fire Weather Watch | FGF | 13 hr |
| May 2, 4:22 AM CDT | Red Flag Warning | FGF | 16 hr |
| May 2, 4:57 PM CDT | Special Weather Statement | FGF | 33 min |
| May 2, 5:39 PM CDT | Special Weather Statement | FGF | 66 min |
| May 2, 5:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 5, 4:45 AM CDT | Red Flag Warning | FGF | 14 hr |
| May 8, 2:52 PM CDT | Frost Advisory | FGF | 18 hr |
| May 13, 12:15 PM CDT | Wind Advisory | FGF | 3 hr |
| May 17, 3:58 AM CDT | Wind Advisory | FGF | 31 hr |
| May 18, 3:21 AM CDT | Freeze Warning | FGF | 30 hr |
| May 18, 5:53 PM CDT | River Flood Warning | FGF | 46 hr |
| May 19, 2:53 PM CDT | Frost Advisory | FGF | 17 hr |
| May 27, 7:18 PM CDT | Special Weather Statement | FGF | 57 min |
| May 28, 2:35 PM CDT | Mesoscale Discussion | SPC | 55 min |
| May 29, 10:34 AM CDT | River Flood Warning | FGF | 7 days |
| Jun 2, 2:28 PM CDT | Mesoscale Discussion | SPC | 92 min |
| Jun 2, 8:54 PM CDT | Mesoscale Discussion | SPC | 66 min |
| Jun 2, 9:00 PM CDT | Severe Thunderstorm Warning | FGF | 30 min |
| Jun 2, 9:19 PM CDT | Severe Thunderstorm Warning | FGF | 56 min |
| Jun 6, 3:05 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Jun 6, 5:05 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 20, 6:03 PM CDT | Severe Thunderstorm Warning | FGF | 37 min |
| Jun 20, 6:13 PM CDT | Severe Thunderstorm Warning | FGF | 31 min |
| Jun 21, 10:41 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 21, 11:25 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Jun 22, 12:38 AM CDT | Special Weather Statement | FGF | 37 min |
| Jun 27, 2:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Jun 27, 2:42 PM CDT | Tornado Watch | SPC | 7 hr |
| Jun 27, 4:58 PM CDT | Tornado Warning | FGF | 47 min |
| Jun 27, 5:42 PM CDT | Tornado Warning | FGF | 48 min |
| Jun 27, 5:54 PM CDT | Mesoscale Discussion | SPC | 66 min |
| Jun 27, 6:14 PM CDT | Tornado Warning | FGF | 46 min |
| Jun 27, 6:55 PM CDT | Tornado Warning | FGF | 35 min |
| Jun 27, 6:59 PM CDT | Tornado Warning | FGF | 12 min |
| Jun 27, 7:30 PM CDT | Severe Thunderstorm Warning | FGF | 30 min |
| Jul 5, 9:54 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 5, 10:40 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 5, 10:58 AM CDT | Severe Thunderstorm Warning | FGF | 62 min |
| Jul 5, 11:33 AM CDT | Severe Thunderstorm Warning | FGF | 38 min |
| Jul 5, 1:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Jul 11, 9:04 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Jul 12, 2:54 PM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 12, 3:06 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 12, 5:53 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jul 12, 6:23 PM CDT | Tornado Warning | FGF | 52 min |
| Jul 12, 8:16 PM CDT | Mesoscale Discussion | SPC | 59 min |
| Jul 12, 11:49 PM CDT | Severe Thunderstorm Warning | FGF | 56 min |
| Jul 13, 12:25 AM CDT | Special Weather Statement | FGF | 65 min |
| Jul 14, 5:19 PM CDT | Special Weather Statement | FGF | 41 min |
| Jul 14, 6:35 PM CDT | Special Weather Statement | FGF | 40 min |
| Jul 15, 1:09 PM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 15, 2:33 PM CDT | Areal Flood Advisory | FGF | 6 hr |
| Jul 16, 2:05 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Jul 17, 1:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 17, 3:43 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 17, 4:50 PM CDT | Severe Thunderstorm Warning | FGF | 55 min |
| Jul 17, 5:37 PM CDT | Severe Thunderstorm Warning | FGF | 53 min |
| Jul 17, 6:02 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jul 17, 6:32 PM CDT | Severe Thunderstorm Warning | FGF | 42 min |
| Jul 17, 6:40 PM CDT | Severe Thunderstorm Warning | FGF | 27 min |
| Jul 17, 6:59 PM CDT | Severe Thunderstorm Warning | FGF | 38 min |
| Jul 17, 8:30 PM CDT | Special Weather Statement | FGF | 30 min |
| Jul 17, 8:59 PM CDT | Special Weather Statement | FGF | 31 min |
| Jul 23, 3:58 PM CDT | Severe Thunderstorm Watch | SPC | 11 hr |
| Jul 23, 10:28 PM CDT | Mesoscale Discussion | SPC | 32 min |
| Jul 23, 10:40 PM CDT | Severe Thunderstorm Warning | FGF | 65 min |
| Jul 23, 10:58 PM CDT | Severe Thunderstorm Warning | FGF | 47 min |
| Jul 23, 11:40 PM CDT | Severe Thunderstorm Warning | FGF | 65 min |
| Jul 24, 12:34 AM CDT | Severe Thunderstorm Warning | FGF | 56 min |
| Jul 24, 12:41 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 25, 4:30 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Jul 28, 1:57 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 28, 3:55 AM CDT | Special Weather Statement | FGF | 65 min |
| Jul 28, 4:02 AM CDT | Wind Advisory | FGF | 39 hr |
| Aug 2, 6:16 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 7, 5:42 PM CDT | Mesoscale Discussion | SPC | 63 min |
| Aug 7, 5:55 PM CDT | Severe Thunderstorm Warning | FGF | 65 min |
| Aug 7, 6:01 PM CDT | Severe Thunderstorm Warning | FGF | 44 min |
| Aug 7, 6:42 PM CDT | Severe Thunderstorm Warning | FGF | 34 min |
| Aug 7, 7:40 PM CDT | Severe Thunderstorm Warning | FGF | 65 min |
| Aug 12, 1:52 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Aug 15, 3:36 AM CDT | Heat Advisory | FGF | 15 hr |
| Aug 15, 6:13 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 15, 8:56 PM CDT | Severe Thunderstorm Warning | FGF | 64 min |
| Aug 15, 9:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Aug 15, 9:48 PM CDT | Severe Thunderstorm Warning | FGF | 57 min |
| Aug 22, 9:42 AM CDT | Wind Advisory | FGF | 33 hr |
| Aug 22, 2:35 PM CDT | Mesoscale Discussion | SPC | 55 min |
| Aug 22, 2:56 PM CDT | Tornado Watch | SPC | 8 hr |
| Sep 25, 3:44 AM CDT | Dense Fog Advisory | FGF | 7 hr |
| Sep 28, 2:29 PM CDT | Frost Advisory | FGF | 18 hr |
| Oct 6, 3:41 PM CDT | Frost Advisory | FGF | 16 hr |
| Oct 11, 10:41 AM CDT | High Wind Watch | FGF | 4 hr |
| Oct 11, 10:41 AM CDT | High Wind Warning | FGF | 29 hr |
| Oct 15, 3:36 AM CDT | Freeze Warning | FGF | 30 hr |
| Oct 28, 4:04 AM CDT | Wind Advisory | FGF | 19 hr |
| Nov 3, 2:46 PM CST | Dense Fog Advisory | FGF | 31 hr |
| Nov 11, 2:10 PM CST | Wind Advisory | FGF | 27 hr |
| Nov 18, 3:50 AM CST | Wind Advisory | FGF | 40 hr |
| Nov 30, 4:23 AM CST | Winter Weather Advisory | FGF | 35 hr |
| Dec 12, 5:03 PM CST | Dense Fog Advisory | FGF | 42 hr |
| Dec 14, 4:05 AM CST | Winter Storm Watch | FGF | 35 hr |
| Dec 15, 2:43 PM CST | Winter Storm Warning | FGF | 28 hr |
| Dec 16, 11:32 AM CST | Winter Weather Advisory | FGF | 8 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 | 23 |
| Tornado Warning | 6 |
| Severe Thunderstorm Watch | 7 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 27 |
| Special Weather Statement | 12 |
| Flooding | |
| River Flood Warning | 2 |
| Areal Flood Advisory | 1 |
| Winter | |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Freezing Rain Advisory | 2 |
| Winter Weather Advisory | 8 |
| Heat | |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 2 |
| Wind Chill Warning | 3 |
| Frost Advisory | 4 |
| Wind Chill Advisory | 16 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 1 |
| Wind Advisory | 14 |
| Fire | |
| Red Flag Warning | 8 |
| Fire Weather Watch | 4 |
| Fog and smoke | |
| Dense Fog Advisory | 3 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20142016
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.