Alert archive / Illinois / Dense Fog Advisories / 2021
Dense Fog Advisories in Illinois, August 2021
6 dense fog advisories in August 2021. An alert counts here when it covered any part of the state, so the counties below add up to more than the state. The archive of dense fog advisories reaches back to 2005.
Dense Fog Advisories by county
Each county as a circle sized by its count in August 2021. Tap one for its archive.
- Dense Fog Advisories
- 6
- Busiest day
- August 1, 20212 dense fog advisories
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 | Counties | Lasted |
|---|---|---|---|---|
| Aug 1, 1:03 AM CDT | Dense Fog Advisory | ILX | Cass, Christian, DeWitt, Fulton, Logan, McLean and 13 more | 7 hr |
| Aug 1, 1:58 AM CDT | Dense Fog Advisory | LSX | Adams, Brown, Calhoun, Greene, Jersey, Macoupin and 2 more | 6 hr |
| Aug 20, 5:23 AM CDT | Dense Fog Advisory | LOT | Cook, Lake, McHenry | 3 hr |
| Aug 22, 2:45 AM CDT | Dense Fog Advisory | ILX | Clark, Clay, Coles, Crawford, Cumberland, Douglas and 6 more | 6 hr |
| Aug 22, 3:43 AM CDT | Dense Fog Advisory | PAH | Edwards, Gallatin, Hamilton, Hardin, Wabash, Wayne and 1 more | 4 hr |
| Aug 23, 3:51 AM CDT | Dense Fog Advisory | ILX | Champaign, Christian, Clark, Clay, Coles, Crawford and 15 more | 4 hr |
By county
Every county with at least one alert. A county page lists each alert that covered it.
- Christian County2
- DeWitt County2
- Logan County2
- Macon County2
- Moultrie County2
- Piatt County2
- Sangamon County2
- Shelby County2
- Clark County2
- Clay County2
- Coles County2
- Crawford County2
- Cumberland County2
- Douglas County2
- Edgar County2
- Effingham County2
- Jasper County2
- Lawrence County2
- Richland County2
- Vermilion County2
- Cass County1
- Fulton County1
- McLean County1
- Mason County1
- Menard County1
- Morgan County1
- Peoria County1
- Schuyler County1
- Scott County1
- Tazewell County1
- Woodford County1
- Adams County1
- Brown County1
- Calhoun County1
- Greene County1
- Jersey County1
- Macoupin County1
- Montgomery County1
- Pike County1
- Cook County1
Nearby
Alerts in force nowTornadoes on recordThe 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. Warning verification from the Mesonet's Cow. Rebuilt daily.