Alert archive / Idaho / Canyon County
Weather alerts in Canyon County, Idaho, 2018
35 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Canyon County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 35
- Warnings
- 10
- Watches
- 3
- Advisories
- 12
- Busiest month
- May14 alerts
- Busiest day
- May 26, 20187 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Canyon County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 6 | 3 | 50% | 2 | 100% | 39 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 Boise, ID: severe thunderstorm warnings | 40 | 6 | 85% | 16 | 44% | 24 min |
| NWS Boise, ID: flash flood warnings | 1 | 0 | 100% | 0 |
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 7, 1:23 AM MST | Dense Fog Advisory | BOI | 37 hr |
| Jan 26, 3:51 AM MST | Winter Weather Advisory | BOI | 49 hr |
| Jan 28, 5:38 AM MST | Dense Fog Advisory | BOI | 5 hr |
| Jan 28, 9:15 PM MST | Dense Fog Advisory | BOI | 15 hr |
| Feb 21, 2:25 PM MST | Winter Weather Advisory | BOI | 22 hr |
| Feb 23, 1:59 PM MST | Winter Weather Advisory | BOI | 30 hr |
| May 6, 2:50 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 15, 3:16 PM MDT | Special Weather Statement | BOI | 44 min |
| May 16, 5:56 PM MDT | Special Weather Statement | BOI | 49 min |
| May 17, 4:40 PM MDT | Special Weather Statement | BOI | 35 min |
| May 20, 8:35 PM MDT | Areal Flood Advisory | BOI | 104 min |
| May 25, 5:08 PM MDT | Severe Thunderstorm Warning | BOI | 67 min |
| May 25, 6:01 PM MDT | Severe Thunderstorm Warning | BOI | 59 min |
| May 25, 6:34 PM MDT | Severe Thunderstorm Warning | BOI | 56 min |
| May 25, 7:00 PM MDT | Severe Thunderstorm Warning | BOI | 60 min |
| May 25, 7:29 PM MDT | Severe Thunderstorm Warning | BOI | 31 min |
| May 25, 8:00 PM MDT | Severe Thunderstorm Warning | BOI | 45 min |
| May 25, 8:45 PM MDT | Special Weather Statement | BOI | 30 min |
| May 26, 12:07 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| May 30, 6:59 PM MDT | Special Weather Statement | BOI | 31 min |
| Jun 20, 7:54 PM MDT | Special Weather Statement | BOI | 51 min |
| Jul 29, 2:05 PM MDT | Excessive Heat Watch | BOI | 23 hr |
| Jul 30, 12:52 PM MDT | Heat Advisory | BOI | 35 hr |
| Aug 8, 8:31 PM MDT | Excessive Heat Warning | BOI | 51 hr |
| Aug 15, 2:03 PM MDT | Fire Weather Watch | BOI | 24 hr |
| Aug 16, 8:08 AM MDT | Red Flag Warning | BOI | 40 hr |
| Aug 17, 1:41 PM MDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 19, 1:40 PM MDT | Red Flag Warning | BOI | 30 hr |
| Oct 11, 9:43 AM MDT | Frost Advisory | BOI | 24 hr |
| Oct 13, 2:32 AM MDT | Freeze Watch | BOI | 11 hr |
| Oct 13, 1:45 PM MDT | Freeze Warning | BOI | 20 hr |
| Nov 22, 9:01 PM MST | Special Weather Statement | BOI | 59 min |
| Nov 29, 3:38 AM MST | Dense Fog Advisory | BOI | 7 hr |
| Nov 30, 2:55 PM MST | Winter Weather Advisory | BOI | 19 hr |
| Dec 24, 10:34 PM MST | Dense Fog Advisory | BOI | 12 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 | 6 |
| Mesoscale Discussion | 3 |
| Special Weather Statement | 7 |
| Flooding | |
| Areal Flood Advisory | 1 |
| Winter | |
| Winter Weather Advisory | 4 |
| Heat | |
| Excessive Heat Warning | 1 |
| Excessive Heat Watch | 1 |
| Heat Advisory | 1 |
| Cold | |
| Freeze Warning | 1 |
| Freeze Watch | 1 |
| Frost Advisory | 1 |
| Fire | |
| Red Flag Warning | 2 |
| Fire Weather Watch | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 5 |
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.