Alert archive / Wyoming / Niobrara County
Weather alerts in Niobrara County, Wyoming, 2017
90 weather alerts in 2017, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Niobrara County and its neighbors
Each county as a circle sized by its count in 2017. Tap one for its archive.
- Alerts
- 90
- Warnings
- 23
- Watches
- 8
- Advisories
- 22
- Busiest month
- June21 alerts
- Busiest day
- May 15, 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.
1 of 1 tornado warnings covering Niobrara County in 2017 had a tornado report inside them.
Niobrara County, 2017
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 1 | 0% | 0 | ||
| Severe thunderstorm warnings | 13 | 4 | 69% | 5 | 40% | 12 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 Cheyenne, WY: tornado warnings | 30 | 14 | 53% | 29 | 86% | 18 min |
| NWS Cheyenne, WY: severe thunderstorm warnings | 120 | 41 | 66% | 134 | 57% | 26 min |
| NWS Cheyenne, WY: flash flood warnings | 4 | 1 | 75% | 2 | 50% | 31 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 4, 3:16 AM MST | Wind Chill Advisory | CYS | 32 hr |
| Jan 5, 3:03 PM MST | Wind Chill Warning | CYS | 20 hr |
| Jan 6, 1:57 PM MST | Wind Chill Advisory | CYS | 19 hr |
| Jan 22, 2:02 PM MST | Winter Storm Watch | CYS | 23 hr |
| Jan 23, 1:30 PM MST | Winter Storm Warning | CYS | 35 hr |
| Jan 31, 3:13 PM MST | Winter Weather Advisory | CYS | 20 hr |
| Feb 1, 2:21 PM MST | Winter Weather Advisory | CYS | 34 hr |
| Feb 19, 2:11 AM MST | High Wind Watch | CYS | 33 hr |
| Feb 19, 1:30 PM MST | High Wind Warning | CYS | 49 hr |
| Feb 21, 3:28 AM MST | Winter Storm Watch | CYS | 34 hr |
| Feb 21, 7:53 PM MST | Winter Storm Warning | CYS | 63 hr |
| Mar 4, 2:44 PM MST | High Wind Watch | CYS | 23 hr |
| Mar 5, 2:54 AM MST | High Wind Warning | CYS | 4 days |
| Mar 5, 1:43 PM MST | High Wind Warning | CYS | 51 hr |
| Mar 31, 3:45 AM MDT | Winter Weather Advisory | CYS | 31 hr |
| Apr 8, 9:15 PM MDT | High Wind Watch | CYS | 17 hr |
| Apr 9, 2:21 PM MDT | Winter Weather Advisory | CYS | 19 hr |
| Apr 27, 4:25 AM MDT | Winter Storm Warning | CYS | 44 hr |
| Apr 27, 4:25 AM MDT | Winter Weather Advisory | CYS | 50 hr |
| May 14, 5:51 PM MDT | Mesoscale Discussion | SPC | 54 min |
| May 14, 6:33 PM MDT | Special Weather Statement | CYS | 42 min |
| May 14, 7:18 PM MDT | Special Weather Statement | CYS | 42 min |
| May 14, 9:48 PM MDT | Special Weather Statement | CYS | 27 min |
| May 15, 3:07 PM MDT | Mesoscale Discussion | SPC | 113 min |
| May 15, 4:40 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 15, 6:01 PM MDT | Special Weather Statement | CYS | 44 min |
| May 15, 6:34 PM MDT | Mesoscale Discussion | SPC | 56 min |
| May 15, 9:53 PM MDT | Mesoscale Discussion | SPC | 67 min |
| May 17, 1:16 AM MDT | Winter Storm Warning | CYS | 59 hr |
| May 28, 2:54 PM MDT | Mesoscale Discussion | SPC | 66 min |
| Jun 5, 4:01 PM MDT | Mesoscale Discussion | SPC | 59 min |
| Jun 5, 6:37 PM MDT | Special Weather Statement | CYS | 38 min |
| Jun 7, 3:31 PM MDT | Severe Thunderstorm Warning | CYS | 38 min |
| Jun 7, 4:11 PM MDT | Special Weather Statement | CYS | 64 min |
| Jun 7, 4:13 PM MDT | Severe Thunderstorm Warning | CYS | 62 min |
| Jun 7, 5:15 PM MDT | Special Weather Statement | CYS | 60 min |
| Jun 7, 5:26 PM MDT | Severe Thunderstorm Warning | CYS | 50 min |
| Jun 7, 6:14 PM MDT | Severe Thunderstorm Warning | CYS | 61 min |
| Jun 12, 11:29 AM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 12, 1:11 PM MDT | Tornado Watch | SPC | 8 hr |
| Jun 12, 5:05 PM MDT | Mesoscale Discussion | SPC | 85 min |
| Jun 12, 5:12 PM MDT | Severe Thunderstorm Warning | CYS | 48 min |
| Jun 12, 5:34 PM MDT | Tornado Warning | CYS | 41 min |
| Jun 12, 8:02 PM MDT | Mesoscale Discussion | SPC | 58 min |
| Jun 27, 2:04 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 27, 3:14 PM MDT | Special Weather Statement | CYS | 46 min |
| Jun 27, 3:35 PM MDT | Special Weather Statement | CYS | 40 min |
| Jun 27, 3:57 PM MDT | Special Weather Statement | CYS | 48 min |
| Jun 27, 4:02 PM MDT | Special Weather Statement | UNR | 28 min |
| Jun 28, 2:28 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 29, 4:47 PM MDT | Special Weather Statement | CYS | 28 min |
| Jul 2, 4:54 PM MDT | Special Weather Statement | CYS | 51 min |
| Jul 2, 5:05 PM MDT | Severe Thunderstorm Warning | CYS | 40 min |
| Jul 10, 3:55 PM MDT | Special Weather Statement | CYS | 50 min |
| Jul 10, 4:08 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 12, 8:51 PM MDT | Special Weather Statement | CYS | 39 min |
| Jul 12, 9:09 PM MDT | Severe Thunderstorm Warning | CYS | 51 min |
| Jul 27, 12:08 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 27, 3:06 PM MDT | Special Weather Statement | CYS | 24 min |
| Jul 27, 4:47 PM MDT | Severe Thunderstorm Warning | CYS | 28 min |
| Jul 27, 8:31 PM MDT | Special Weather Statement | CYS | 44 min |
| Aug 1, 6:52 PM MDT | Mesoscale Discussion | SPC | 83 min |
| Aug 9, 6:49 PM MDT | Special Weather Statement | CYS | 41 min |
| Aug 11, 4:15 PM MDT | Severe Thunderstorm Warning | CYS | 32 min |
| Aug 13, 5:46 PM MDT | Special Weather Statement | CYS | 44 min |
| Aug 13, 6:23 PM MDT | Special Weather Statement | CYS | 37 min |
| Aug 13, 6:54 PM MDT | Special Weather Statement | CYS | 51 min |
| Aug 13, 7:13 PM MDT | Severe Thunderstorm Warning | CYS | 28 min |
| Aug 13, 7:35 PM MDT | Severe Thunderstorm Warning | CYS | 40 min |
| Aug 14, 5:55 PM MDT | Special Weather Statement | CYS | 35 min |
| Aug 14, 6:07 PM MDT | Severe Thunderstorm Warning | CYS | 23 min |
| Aug 14, 6:28 PM MDT | Severe Thunderstorm Warning | CYS | 47 min |
| Aug 24, 5:36 PM MDT | Special Weather Statement | CYS | 24 min |
| Sep 16, 2:08 PM MDT | Frost Advisory | CYS | 18 hr |
| Sep 25, 1:55 PM MDT | Frost Advisory | CYS | 17 hr |
| Sep 26, 12:50 PM MDT | Frost Advisory | CYS | 18 hr |
| Oct 8, 3:11 AM MDT | Winter Weather Advisory | CYS | 33 hr |
| Nov 1, 3:38 AM MDT | Winter Weather Advisory | CYS | 29 hr |
| Dec 1, 1:53 PM MST | Winter Storm Watch | CYS | 47 hr |
| Dec 2, 1:05 PM MST | Winter Storm Warning | CYS | 46 hr |
| Dec 3, 2:47 AM MST | Winter Weather Advisory | CYS | 32 hr |
| Dec 20, 2:37 AM MST | Winter Weather Advisory | CYS | 35 hr |
| Dec 22, 2:14 PM MST | Winter Weather Advisory | CYS | 32 hr |
| Dec 23, 10:38 PM MST | Wind Chill Advisory | CYS | 9 hr |
| Dec 24, 1:14 PM MST | Winter Weather Advisory | CYS | 37 hr |
| Dec 24, 8:04 PM MST | Wind Chill Advisory | CYS | 6 hr |
| Dec 25, 5:38 PM MST | Wind Chill Advisory | CYS | 13 hr |
| Dec 26, 12:47 PM MST | Wind Chill Advisory | CYS | 19 hr |
| Dec 29, 10:16 AM MST | Wind Chill Advisory | CYS | 23 hr |
| Dec 30, 2:31 PM MST | Wind Chill Advisory | CYS | 40 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20162018
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.