Alert archive / Illinois / Grundy County
Weather alerts in Grundy County, Illinois, 2022
122 weather alerts in 2022, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Grundy County and its neighbors
Each county as a circle sized by its count in 2022. Tap one for its archive.
- Alerts
- 122
- Warnings
- 23
- Watches
- 21
- Advisories
- 46
- Busiest month
- February26 alerts
- Busiest day
- February 17, 202210 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Grundy County, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 9 | 6 | 33% | 2 | 100% | 11 min |
| Flash flood warnings | 2 | 1 | 50% | 0 |
Each office's whole area, 2022
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Chicago, IL: tornado warnings | 15 | 3 | 80% | 15 | 60% | 13 min |
| NWS Chicago, IL: severe thunderstorm warnings | 148 | 102 | 31% | 466 | 77% | 26 min |
| NWS Chicago, IL: flash flood warnings | 19 | 8 | 58% | 33 | 79% | 95 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, 2:27 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Jan 4, 3:43 AM CST | Winter Weather Advisory | LOT | 41 hr |
| Jan 6, 1:52 PM CST | Wind Chill Advisory | LOT | 19 hr |
| Jan 7, 2:17 PM CST | Winter Weather Advisory | LOT | 34 hr |
| Jan 7, 9:21 PM CST | River Flood Advisory | LOT | 13 hr |
| Jan 8, 10:35 AM CST | River Flood Warning | LOT | 21 days |
| Jan 12, 10:57 AM CST | River Flood Advisory | LOT | 5 days |
| Jan 13, 3:47 PM CST | Dense Fog Advisory | LOT | 17 hr |
| Jan 22, 9:21 AM CST | Winter Weather Advisory | LOT | 32 hr |
| Jan 23, 3:17 PM CST | Winter Weather Advisory | LOT | 22 hr |
| Jan 25, 3:13 AM CST | Wind Chill Advisory | LOT | 31 hr |
| Jan 31, 3:41 AM CST | Winter Storm Watch | LOT | 23 hr |
| Jan 31, 2:07 PM CST | Winter Storm Warning | LOT | 3 days |
| Feb 2, 1:13 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 2, 7:11 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Feb 15, 7:57 AM CST | River Flood Advisory | LOT | 51 hr |
| Feb 15, 3:02 PM CST | Winter Storm Watch | LOT | 13 hr |
| Feb 16, 3:24 AM CST | Wind Advisory | LOT | 15 hr |
| Feb 16, 3:55 AM CST | Winter Storm Warning | LOT | 44 hr |
| Feb 16, 9:32 PM CST | Areal Flood Advisory | LOT | 12 hr |
| Feb 17, 2:42 AM CST | Areal Flood Advisory | LOT | 9 hr |
| Feb 17, 9:21 AM CST | Areal Flood Advisory | LOT | 3 hr |
| Feb 17, 10:17 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Feb 17, 10:19 AM CST | Flash Flood Warning | LOT | 7 hr |
| Feb 17, 10:42 AM CST | River Flood Warning | LOT | 24 hr |
| Feb 17, 10:50 AM CST | River Flood Advisory | LOT | 19 hr |
| Feb 17, 11:07 AM CST | River Flood Advisory | LOT | 23 hr |
| Feb 17, 3:17 PM CST | Mesoscale Discussion | SPC | 118 min |
| Feb 17, 4:23 PM CST | Flash Flood Warning | LOT | 4 hr |
| Feb 17, 8:34 PM CST | Flash Flood Watch | LOT | 4 days |
| Feb 18, 10:26 AM CST | Winter Weather Advisory | LOT | 23 hr |
| Feb 18, 11:02 AM CST | River Flood Advisory | LOT | 5 days |
| Feb 18, 10:05 PM CST | Snow Squall Warning | LOT | 55 min |
| Feb 21, 2:01 PM CST | Flood Watch | LOT | 22 hr |
| Feb 22, 12:59 AM CST | Dense Fog Advisory | LOT | 9 hr |
| Feb 22, 8:38 AM CST | Flash Flood Watch | LOT | 26 hr |
| Feb 22, 11:09 AM CST | Areal Flood Advisory | LOT | 3 hr |
| Feb 22, 8:57 PM CST | River Flood Advisory | LOT | 35 hr |
| Feb 23, 2:50 PM CST | Winter Weather Advisory | LOT | 39 hr |
| Mar 5, 3:25 AM CST | Wind Advisory | LOT | 30 hr |
| Mar 5, 8:36 PM CST | Severe Thunderstorm Watch | SPC | 5 hr |
| Mar 5, 10:14 PM CST | Severe Thunderstorm Warning | LOT | 76 min |
| Mar 5, 10:32 PM CST | Mesoscale Discussion | SPC | 88 min |
| Mar 6, 2:36 PM CST | Winter Weather Advisory | LOT | 21 hr |
| Mar 25, 3:03 AM CDT | Wind Advisory | LOT | 19 hr |
| Mar 25, 2:18 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Mar 31, 10:43 AM CDT | River Flood Watch | LOT | 10 hr |
| Apr 13, 1:48 PM CDT | Mesoscale Discussion | SPC | 87 min |
| Apr 13, 2:08 PM CDT | Wind Advisory | LOT | 21 hr |
| Apr 13, 3:39 PM CDT | Special Weather Statement | LOT | 51 min |
| Apr 14, 10:41 AM CDT | High Wind Warning | LOT | 8 hr |
| Apr 24, 10:56 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Apr 25, 3:01 AM CDT | Freeze Warning | LOT | 24 hr |
| Apr 26, 3:20 AM CDT | Freeze Warning | LOT | 29 hr |
| Apr 30, 12:32 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Apr 30, 1:46 PM CDT | Tornado Watch | SPC | 8 hr |
| Apr 30, 3:20 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Apr 30, 3:49 PM CDT | Severe Thunderstorm Warning | LOT | 41 min |
| Apr 30, 5:57 PM CDT | Severe Thunderstorm Warning | LOT | 48 min |
| Apr 30, 6:02 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Apr 30, 6:25 PM CDT | Severe Thunderstorm Warning | LOT | 50 min |
| May 11, 5:15 PM CDT | Mesoscale Discussion | SPC | 60 min |
| May 19, 1:56 AM CDT | Dense Fog Advisory | LOT | 7 hr |
| May 20, 12:05 PM CDT | Wind Advisory | LOT | 7 hr |
| May 20, 7:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| May 21, 12:07 AM CDT | Special Weather Statement | LOT | 38 min |
| May 25, 3:37 PM CDT | Mesoscale Discussion | SPC | 113 min |
| May 26, 2:45 PM CDT | Flood Watch | LOT | 16 hr |
| May 31, 3:40 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 6, 7:49 PM CDT | Areal Flood Advisory | LOT | 4 hr |
| Jun 11, 3:33 AM CDT | Dense Fog Advisory | LOT | 4 hr |
| Jun 12, 3:37 PM CDT | Heat Advisory | LOT | 3 days |
| Jun 13, 5:38 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 14, 3:46 AM CDT | Excessive Heat Warning | LOT | 40 hr |
| Jun 15, 7:53 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Jun 20, 2:40 PM CDT | Heat Advisory | LOT | 29 hr |
| Jul 4, 1:40 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 4, 2:22 PM CDT | Heat Advisory | LOT | 30 hr |
| Jul 4, 3:50 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Jul 4, 3:51 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jul 5, 4:34 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 5, 10:24 PM CDT | Mesoscale Discussion | SPC | 96 min |
| Jul 5, 11:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 8, 12:03 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Jul 23, 2:52 AM CDT | Flood Watch | LOT | 9 hr |
| Jul 23, 4:01 AM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jul 23, 5:35 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Jul 23, 2:28 PM CDT | Flood Watch | LOT | 20 hr |
| Aug 2, 2:18 PM CDT | Heat Advisory | LOT | 25 hr |
| Aug 3, 1:25 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 7, 10:59 AM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 8, 10:04 AM CDT | Flood Watch | LOT | 3 hr |
| Aug 20, 3:21 PM CDT | Special Weather Statement | LOT | 39 min |
| Aug 20, 3:26 PM CDT | Severe Thunderstorm Warning | LOT | 49 min |
| Aug 20, 4:11 PM CDT | Special Weather Statement | LOT | 49 min |
| Aug 21, 1:19 AM CDT | Dense Fog Advisory | LOT | 8 hr |
| Aug 28, 1:09 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 29, 9:42 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 29, 10:12 AM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 29, 12:02 PM CDT | Severe Thunderstorm Warning | LOT | 73 min |
| Aug 29, 12:19 PM CDT | Severe Thunderstorm Warning | LOT | 56 min |
| Aug 29, 12:44 PM CDT | Severe Thunderstorm Warning | LOT | 61 min |
| Aug 29, 12:53 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 29, 7:29 PM CDT | Special Weather Statement | LOT | 46 min |
| Sep 15, 2:36 AM CDT | Dense Fog Advisory | LOT | 6 hr |
| Sep 18, 9:28 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Oct 7, 3:06 AM CDT | Frost Advisory | LOT | 29 hr |
| Oct 7, 3:06 AM CDT | Freeze Watch | LOT | 11 hr |
| Oct 13, 2:26 PM CDT | Freeze Warning | LOT | 13 hr |
| Oct 31, 3:07 AM CDT | Dense Fog Advisory | LOT | 9 hr |
| Nov 4, 3:18 AM CDT | Wind Advisory | LOT | 40 hr |
| Nov 5, 2:21 AM CDT | High Wind Warning | LOT | 17 hr |
| Nov 5, 9:51 AM CDT | Mesoscale Discussion | SPC | 114 min |
| Nov 5, 10:52 AM CDT | Severe Thunderstorm Warning | LOT | 57 min |
| Nov 14, 2:27 PM CST | Winter Weather Advisory | LOT | 35 hr |
| Nov 29, 3:40 AM CST | Wind Advisory | LOT | 19 hr |
| Dec 2, 3:39 AM CST | Wind Advisory | LOT | 29 hr |
| Dec 19, 2:30 PM CST | Winter Storm Watch | LOT | 44 hr |
| Dec 21, 10:41 AM CST | Winter Storm Warning | LOT | 3 days |
| Dec 22, 10:59 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Dec 24, 3:19 AM CST | Winter Weather Advisory | LOT | 9 hr |
| Dec 24, 1:05 PM CST | Wind Chill Advisory | LOT | 21 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 archive20212023
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.