Alert archive / Illinois / McHenry County
Weather alerts in McHenry County, Illinois, 2021
100 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
McHenry County and its neighbors
Each county as a circle sized by its count in 2021. Tap one for its archive.
- Alerts
- 100
- Warnings
- 17
- Watches
- 15
- Advisories
- 37
- Busiest month
- August29 alerts
- Busiest day
- August 10, 20216 alerts
Over time
By month
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, 3:04 PM CST | Dense Fog Advisory | LOT | 20 hr |
| Jan 3, 3:37 PM CST | Dense Fog Advisory | LOT | 29 hr |
| Jan 5, 3:18 PM CST | Dense Fog Advisory | LOT | 19 hr |
| Jan 24, 3:05 AM CST | Winter Storm Watch | LOT | 12 hr |
| Jan 24, 2:55 PM CST | Winter Storm Warning | LOT | 48 hr |
| Jan 29, 3:23 AM CST | Winter Storm Watch | LOT | 24 hr |
| Jan 29, 2:38 PM CST | Winter Storm Warning | LOT | 51 hr |
| Feb 3, 2:29 PM CST | Winter Weather Advisory | LOT | 46 hr |
| Feb 6, 3:34 AM CST | Wind Chill Advisory | LOT | 32 hr |
| Feb 8, 3:10 PM CST | Wind Chill Advisory | LOT | 19 hr |
| Feb 13, 3:33 AM CST | Wind Chill Warning | LOT | 31 hr |
| Feb 13, 3:33 AM CST | Wind Chill Advisory | LOT | 56 hr |
| Feb 14, 2:19 PM CST | Winter Weather Advisory | LOT | 43 hr |
| Feb 28, 6:29 AM CST | Dense Fog Advisory | LOT | 6 hr |
| Mar 10, 3:25 AM CST | Wind Advisory | LOT | 23 hr |
| Mar 15, 2:58 AM CDT | Winter Weather Advisory | LOT | 16 hr |
| Mar 17, 2:35 PM CDT | Wind Advisory | LOT | 28 hr |
| Apr 7, 3:20 PM CDT | Special Weather Statement | LOT | 40 min |
| Apr 19, 3:45 AM CDT | Freeze Watch | LOT | 11 hr |
| Apr 19, 2:58 PM CDT | Freeze Warning | LOT | 42 hr |
| Apr 21, 3:22 AM CDT | Freeze Warning | LOT | 29 hr |
| Apr 29, 6:01 PM CDT | Special Weather Statement | LOT | 59 min |
| Apr 30, 2:50 PM CDT | Wind Advisory | LOT | 28 hr |
| May 7, 2:07 PM CDT | Frost Advisory | LOT | 18 hr |
| May 10, 2:23 PM CDT | Frost Advisory | LOT | 18 hr |
| May 11, 2:11 PM CDT | Frost Advisory | LOT | 17 hr |
| May 12, 2:41 PM CDT | Frost Advisory | LOT | 16 hr |
| Jun 11, 1:07 PM CDT | Special Weather Statement | LOT | 113 min |
| Jun 12, 1:23 PM CDT | Special Weather Statement | LOT | 112 min |
| Jun 18, 3:34 AM CDT | Special Weather Statement | LOT | 41 min |
| Jun 20, 9:40 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Jun 20, 11:08 PM CDT | Areal Flood Advisory | LOT | 4 hr |
| Jun 28, 3:01 AM CDT | Flash Flood Watch | LOT | 40 hr |
| Jun 28, 8:09 PM CDT | Special Weather Statement | LOT | 36 min |
| Jul 7, 2:02 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 14, 11:45 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 14, 2:01 PM CDT | Mesoscale Discussion | SPC | 119 min |
| Jul 14, 11:17 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Jul 14, 11:57 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jul 15, 2:14 AM CDT | Mesoscale Discussion | SPC | 61 min |
| Jul 24, 3:00 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jul 24, 3:32 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jul 28, 3:35 AM CDT | Special Weather Statement | LOT | 25 min |
| Jul 28, 3:59 AM CDT | Special Weather Statement | LOT | 31 min |
| Jul 29, 12:32 AM CDT | Mesoscale Discussion | SPC | 88 min |
| Jul 29, 1:00 AM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jul 29, 1:23 AM CDT | Severe Thunderstorm Warning | LOT | 82 min |
| Jul 29, 1:34 AM CDT | Mesoscale Discussion | SPC | 86 min |
| Jul 29, 1:49 AM CDT | Severe Thunderstorm Warning | LOT | 71 min |
| Aug 6, 3:23 PM CDT | Mesoscale Discussion | SPC | 97 min |
| Aug 9, 11:49 AM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 9, 12:18 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 9, 2:43 PM CDT | Tornado Watch | SPC | 9 hr |
| Aug 9, 2:46 PM CDT | Heat Advisory | LOT | 28 hr |
| Aug 9, 4:12 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 10, 3:07 PM CDT | Heat Advisory | LOT | 28 hr |
| Aug 10, 3:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 10, 3:47 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 10, 5:51 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Aug 10, 6:16 PM CDT | Severe Thunderstorm Warning | LOT | 74 min |
| Aug 10, 6:34 PM CDT | Severe Thunderstorm Warning | LOT | 86 min |
| Aug 11, 9:46 AM CDT | Severe Thunderstorm Warning | LOT | 59 min |
| Aug 11, 7:35 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Aug 11, 8:22 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 11, 11:06 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Aug 19, 4:44 PM CDT | Special Weather Statement | LOT | 46 min |
| Aug 20, 5:23 AM CDT | Dense Fog Advisory | LOT | 3 hr |
| Aug 24, 3:09 PM CDT | Mesoscale Discussion | SPC | 66 min |
| Aug 24, 3:55 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 24, 4:58 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 24, 5:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 24, 5:40 PM CDT | Flash Flood Warning | LOT | 4 hr |
| Aug 24, 6:09 PM CDT | Severe Thunderstorm Warning | LOT | 66 min |
| Aug 24, 7:08 PM CDT | Severe Thunderstorm Warning | LOT | 67 min |
| Aug 24, 7:31 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 28, 5:26 PM CDT | Areal Flood Advisory | LOT | 2 hr |
| Aug 29, 1:05 PM CDT | Special Weather Statement | LOT | 40 min |
| Aug 29, 1:18 PM CDT | Mesoscale Discussion | SPC | 87 min |
| Sep 7, 12:25 PM CDT | Mesoscale Discussion | SPC | 65 min |
| Sep 7, 12:37 PM CDT | Severe Thunderstorm Warning | LOT | 53 min |
| Sep 7, 1:12 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Sep 7, 1:20 PM CDT | Severe Thunderstorm Warning | LOT | 55 min |
| Sep 7, 2:15 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Sep 20, 11:44 PM CDT | Special Weather Statement | LOT | 31 min |
| Oct 8, 5:52 AM CDT | Dense Fog Advisory | LOT | 3 hr |
| Oct 8, 9:45 PM CDT | Dense Fog Advisory | LOT | 6 hr |
| Oct 11, 12:37 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Oct 11, 3:10 PM CDT | Tornado Watch | SPC | 6 hr |
| Oct 22, 1:29 PM CDT | Frost Advisory | LOT | 19 hr |
| Oct 24, 3:10 AM CDT | Wind Advisory | LOT | 36 hr |
| Oct 31, 2:37 AM CDT | Freeze Warning | LOT | 30 hr |
| Nov 27, 8:13 AM CST | Winter Weather Advisory | LOT | 3 hr |
| Dec 3, 10:49 PM CST | Dense Fog Advisory | LOT | 3 hr |
| Dec 5, 1:54 PM CST | Wind Advisory | LOT | 22 hr |
| Dec 10, 2:56 AM CST | Wind Advisory | LOT | 36 hr |
| Dec 14, 3:19 AM CST | High Wind Watch | LOT | 24 hr |
| Dec 15, 3:09 AM CST | High Wind Warning | LOT | 30 hr |
| Dec 27, 8:11 AM CST | Dense Fog Advisory | LOT | 4 hr |
| Dec 27, 2:03 PM CST | Winter Weather Advisory | LOT | 28 hr |
| Dec 28, 8:59 AM CST | Mesoscale Discussion | SPC | 5 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 | 9 |
| Severe Thunderstorm Watch | 8 |
| Tornado Watch | 2 |
| Mesoscale Discussion | 20 |
| Special Weather Statement | 11 |
| Flooding | |
| Flash Flood Warning | 1 |
| Flash Flood Watch | 1 |
| Areal Flood Advisory | 7 |
| Winter | |
| Winter Storm Warning | 2 |
| Winter Storm Watch | 2 |
| Winter Weather Advisory | 5 |
| Heat | |
| Heat Advisory | 2 |
| Cold | |
| Freeze Warning | 3 |
| Wind Chill Warning | 1 |
| Freeze Watch | 1 |
| Frost Advisory | 5 |
| Wind Chill Advisory | 3 |
| Wind and dust | |
| High Wind Warning | 1 |
| High Wind Watch | 1 |
| Wind Advisory | 6 |
| Fog and smoke | |
| Dense Fog Advisory | 9 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20202022
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. Rebuilt daily.