Alert archive / Illinois / McHenry County / 2026
Weather alerts in McHenry County, Illinois, August 2026
17 weather alerts in August 2026, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
- Alerts
- 17
- Warnings
- 4
- Watches
- 5
- Advisories
- 3
- Busiest day
- August 11, 20265 alerts
Over time
By day
Days in UTC, the clock the archive keeps.
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 |
|---|---|---|---|
| Aug 9, 9:20 AM CDT | Mesoscale Discussion | SPC | 85 min |
| Aug 9, 9:46 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 9, 12:43 PM CDT | Areal Flood Advisory | LOT | 3 hr |
| Aug 9, 5:03 PM CDT | Flood Watch | LOT | 10 hr |
| Aug 9, 8:14 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 9, 8:43 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 10, 12:47 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 11, 3:11 AM CDT | Severe Thunderstorm Warning | LOT | 51 min |
| Aug 11, 3:49 AM CDT | Severe Thunderstorm Warning | LOT | 27 min |
| Aug 11, 7:22 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 11, 9:00 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 11, 9:38 AM CDT | Severe Thunderstorm Warning | LOT | 67 min |
| Aug 18, 5:29 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 21, 2:17 PM CDT | Severe Thunderstorm Warning | LOT | 43 min |
| Aug 21, 2:57 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| Aug 31, 12:24 PM CDT | Heat Advisory | LOT | 33 hr |
| Aug 31, 12:24 PM CDT | Heat Advisory | LOT | 3 days |
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 | 4 |
| Severe Thunderstorm Watch | 4 |
| Mesoscale Discussion | 5 |
| Flooding | |
| Flood Watch | 1 |
| Areal Flood Advisory | 1 |
| Heat | |
| Heat Advisory | 2 |
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive2025
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.