Alert archive / Wisconsin / Clark County
Weather alerts in Clark County, Wisconsin, 2009
57 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Clark County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 57
- Warnings
- 12
- Watches
- 10
- Advisories
- 21
- Busiest month
- August12 alerts
- Busiest day
- April 25, 20094 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Clark County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 5 | 4 | 20% | 6 | 83% | 20 min |
| Flash flood warnings | 2 | 1 | 50% | 0 |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS La Crosse, WI: tornado warnings | 24 | 7 | 71% | 14 | 71% | 18 min |
| NWS La Crosse, WI: severe thunderstorm warnings | 78 | 50 | 36% | 151 | 85% | 25 min |
| NWS La Crosse, WI: flash flood warnings | 15 | 10 | 33% | 22 | 77% | 131 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 3, 3:48 AM CST | Winter Weather Advisory | ARX | 24 hr |
| Jan 3, 6:16 PM CST | Mesoscale Discussion | SPC | 5 hr |
| Jan 8, 2:37 PM CST | Winter Weather Advisory | ARX | 23 hr |
| Jan 12, 3:41 AM CST | Wind Chill Advisory | ARX | 32 hr |
| Jan 14, 4:17 AM CST | Wind Chill Warning | ARX | 56 hr |
| Jan 23, 3:41 AM CST | Wind Chill Advisory | ARX | 32 hr |
| Jan 24, 2:56 PM CST | Wind Chill Advisory | ARX | 21 hr |
| Feb 2, 3:20 PM CST | Wind Chill Advisory | ARX | 19 hr |
| Feb 16, 3:33 PM CST | Winter Storm Watch | ARX | 12 hr |
| Feb 17, 3:43 AM CST | Winter Weather Advisory | ARX | 35 hr |
| Feb 24, 3:21 PM CST | Winter Storm Watch | ARX | 36 hr |
| Feb 25, 3:36 PM CST | Winter Storm Warning | ARX | 32 hr |
| Feb 26, 11:47 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Mar 5, 9:18 PM CST | Dense Fog Advisory | ARX | 7 hr |
| Mar 7, 3:39 PM CST | Winter Weather Advisory | ARX | 24 hr |
| Mar 8, 12:58 PM CDT | Mesoscale Discussion | SPC | 4 hr |
| Mar 10, 4:08 AM CDT | Wind Advisory | ARX | 30 hr |
| Mar 30, 2:29 PM CDT | Winter Weather Advisory | ARX | 21 hr |
| Apr 24, 3:18 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 24, 4:45 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Apr 24, 6:31 PM CDT | Severe Thunderstorm Warning | ARX | 59 min |
| Apr 24, 7:42 PM CDT | Mesoscale Discussion | SPC | 63 min |
| Apr 24, 8:04 PM CDT | Severe Thunderstorm Warning | ARX | 41 min |
| Apr 24, 8:41 PM CDT | Severe Thunderstorm Warning | ARX | 34 min |
| Apr 24, 9:40 PM CDT | Mesoscale Discussion | SPC | 65 min |
| May 16, 4:04 AM CDT | Frost Advisory | ARX | 27 hr |
| Jun 18, 7:00 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Jun 18, 7:34 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 27, 2:10 PM CDT | Mesoscale Discussion | SPC | 65 min |
| Jul 27, 2:15 PM CDT | Severe Thunderstorm Warning | ARX | 60 min |
| Aug 2, 9:40 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Aug 2, 11:21 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Aug 2, 11:37 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 3, 12:06 AM CDT | Severe Thunderstorm Warning | ARX | 41 min |
| Aug 8, 12:49 AM CDT | Flash Flood Warning | ARX | 6 hr |
| Aug 8, 1:29 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 8, 3:41 AM CDT | Flash Flood Watch | ARX | 23 hr |
| Aug 8, 3:46 PM CDT | Tornado Watch | SPC | 8 hr |
| Aug 8, 11:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Aug 14, 1:10 AM CDT | Flash Flood Warning | ARX | 6 hr |
| Aug 19, 4:49 PM CDT | Tornado Watch | SPC | 5 hr |
| Aug 19, 7:45 PM CDT | Mesoscale Discussion | SPC | 90 min |
| Sep 25, 2:27 AM CDT | Dense Fog Advisory | ARX | 6 hr |
| Sep 26, 3:26 PM CDT | Wind Advisory | ARX | 52 hr |
| Sep 29, 4:02 AM CDT | Frost Advisory | ARX | 28 hr |
| Oct 27, 3:37 AM CDT | Dense Fog Advisory | ARX | 6 hr |
| Nov 20, 9:48 PM CST | Dense Fog Advisory | ARX | 12 hr |
| Dec 6, 3:11 PM CST | Winter Storm Watch | ARX | 25 hr |
| Dec 7, 3:50 PM CST | Blizzard Warning | ARX | 48 hr |
| Dec 7, 3:50 PM CST | Winter Storm Warning | ARX | 22 hr |
| Dec 9, 3:34 PM CST | Wind Chill Advisory | ARX | 19 hr |
| Dec 10, 3:14 PM CST | Wind Chill Advisory | ARX | 18 hr |
| Dec 13, 3:20 AM CST | Winter Weather Advisory | ARX | 33 hr |
| Dec 21, 3:34 PM CST | Winter Storm Watch | ARX | 36 hr |
| Dec 23, 3:58 AM CST | Winter Storm Warning | ARX | 48 hr |
| Dec 24, 11:57 AM CST | Winter Weather Advisory | ARX | 27 hr |
| Dec 24, 6:28 PM CST | Mesoscale Discussion | SPC | 4 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 | 5 |
| Severe Thunderstorm Watch | 3 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 14 |
| Flooding | |
| Flash Flood Warning | 2 |
| Flash Flood Watch | 1 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 3 |
| Winter Storm Watch | 4 |
| Winter Weather Advisory | 7 |
| Cold | |
| Wind Chill Warning | 1 |
| Frost Advisory | 2 |
| Wind Chill Advisory | 6 |
| Wind and dust | |
| Wind Advisory | 2 |
| Fog and smoke | |
| Dense Fog Advisory | 4 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20082010
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.