Dense Fog Advisories in Illinois, 2016

Dense Fog Advisories by county

Each county as a circle sized by its count in 2016. Tap one for its archive.

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	Counties	Lasted
Jan 8, 6:21 AM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more	17 hr
Jan 8, 8:41 AM CST	Dense Fog Advisory	ILX	Cass, DeWitt, Fulton, Knox, Logan, McLean and 8 more	3 hr
Jan 8, 2:16 PM CST	Dense Fog Advisory	LOT	Boone, DeKalb, Kane, Kendall, Lake, LaSalle and 4 more	13 hr
Feb 1, 10:03 AM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more	4 hr
Feb 1, 11:19 AM CST	Dense Fog Advisory	LOT	Boone, DeKalb, LaSalle, Lee, Ogle, Winnebago	3 hr
Feb 1, 5:50 PM CST	Dense Fog Advisory	LOT	Boone, DeKalb, DuPage, Grundy, Kane, Kendall and 6 more	8 hr
Feb 1, 9:14 PM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Henry, Jo Daviess, Putnam, Rock Island and 2 more	6 hr
Feb 2, 5:31 PM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more	9 hr
Feb 2, 7:09 PM CST	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Coles, DeWitt, Douglas and 21 more	8 hr
Feb 2, 7:15 PM CST	Dense Fog Advisory	LSX	Adams, Brown, Greene, Macoupin, Pike	4 hr
Feb 2, 9:55 PM CST	Dense Fog Advisory	LOT	Boone, DeKalb, DuPage, Ford, Grundy, Iroquois and 10 more	7 hr
Feb 3, 2:54 AM CST	Dense Fog Advisory	DVN	Carroll, Jo Daviess, Stephenson, Whiteside	3 hr
Feb 15, 3:31 AM CST	Dense Fog Advisory	LSX	Adams, Bond, Brown, Calhoun, Clinton, Fayette and 11 more	8 hr
Feb 15, 4:30 AM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more	6 hr
Feb 15, 7:14 AM CST	Dense Fog Advisory	PAH	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	4 hr
Feb 15, 7:25 AM CST	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Clark, Clay, Coles and 29 more	4 hr
Feb 15, 11:14 AM CST	Dense Fog Advisory	PAH	Alexander, Edwards, Gallatin, Hamilton, Hardin, Johnson and 8 more	3 hr
Feb 16, 1:09 AM CST	Dense Fog Advisory	PAH	Alexander, Franklin, Gallatin, Hamilton, Hardin, Jackson and 8 more	8 hr
Feb 20, 3:30 AM CST	Dense Fog Advisory	ILX	Clay, Crawford, Effingham, Jasper, Lawrence, Richland	6 hr
Feb 20, 3:32 AM CST	Dense Fog Advisory	PAH	Edwards, Franklin, Gallatin, Hamilton, Jackson, Jefferson and 6 more	5 hr
Mar 13, 3:25 AM CDT	Dense Fog Advisory	LSX	Adams, Brown, Pike	7 hr
Mar 14, 12:59 AM CDT	Dense Fog Advisory	DVN	Hancock, Henderson, McDonough, Mercer, Warren	9 hr
Mar 14, 1:02 AM CDT	Dense Fog Advisory	LSX	Adams, Bond, Brown, Calhoun, Fayette, Greene and 7 more	9 hr
Mar 14, 3:12 AM CDT	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Coles, DeWitt, Douglas and 19 more	6 hr
Mar 15, 1:29 AM CDT	Dense Fog Advisory	ILX	Champaign, Clark, Coles, DeWitt, Douglas, Edgar and 8 more	8 hr
Apr 21, 3:42 AM CDT	Dense Fog Advisory	DVN	Carroll, Henderson, Henry, Jo Daviess, McDonough, Mercer and 4 more	5 hr
Apr 21, 4:09 AM CDT	Dense Fog Advisory	ILX	Cass, Fulton, Knox, Morgan, Schuyler, Scott	5 hr
Apr 24, 3:23 AM CDT	Dense Fog Advisory	ILX	Clark, Clay, Crawford, Cumberland, Effingham, Jasper and 2 more	6 hr
Apr 24, 3:32 AM CDT	Dense Fog Advisory	PAH	Edwards, Franklin, Gallatin, Hamilton, Hardin, Jefferson and 9 more	5 hr
May 10, 10:45 PM CDT	Dense Fog Advisory	LOT	Boone, DeKalb, DuPage, Ford, Grundy, Iroquois and 10 more	11 hr
May 11, 1:44 AM CDT	Dense Fog Advisory	PAH	Edwards, Franklin, Gallatin, Hamilton, Hardin, Jackson and 10 more	7 hr
May 11, 1:53 AM CDT	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Clark, Clay, Coles and 29 more	7 hr
May 11, 3:19 AM CDT	Dense Fog Advisory	LSX	Bond, Brown, Calhoun, Clinton, Fayette, Greene and 10 more	6 hr
May 11, 4:31 AM CDT	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, McDonough and 6 more	5 hr
May 11, 8:54 PM CDT	Dense Fog Advisory	LOT	Lake	6 hr
Jun 23, 5:05 AM CDT	Dense Fog Advisory	LOT	Boone, DeKalb, DuPage, Grundy, Kane, Kendall and 6 more	4 hr
Jun 23, 5:09 AM CDT	Dense Fog Advisory	ILX	Knox, Marshall, Stark	4 hr
Jun 23, 5:11 AM CDT	Dense Fog Advisory	DVN	Bureau, Carroll, Henry, Jo Daviess, Putnam, Stephenson and 1 more	4 hr
Jun 27, 2:55 AM CDT	Dense Fog Advisory	LSX	Adams, Brown, Pike	6 hr
Jul 5, 3:00 AM CDT	Dense Fog Advisory	ILX	Cass, Christian, Clark, Clay, Coles, Crawford and 11 more	5 hr
Jul 5, 3:09 AM CDT	Dense Fog Advisory	PAH	Edwards, Jackson, Jefferson, Perry, Wabash, Wayne	6 hr
Jul 5, 3:15 AM CDT	Dense Fog Advisory	LSX	Bond, Calhoun, Clinton, Fayette, Greene, Jersey and 8 more	5 hr
Jul 7, 3:55 AM CDT	Dense Fog Advisory	LSX	Adams, Bond, Brown, Calhoun, Clinton, Fayette and 11 more	3 hr
Jul 7, 5:14 AM CDT	Dense Fog Advisory	PAH	Franklin, Hamilton, Jackson, Jefferson, Perry, Saline and 2 more	3 hr
Jul 8, 4:20 AM CDT	Dense Fog Advisory	LOT	DuPage, Grundy, Kane, Kankakee, Kendall, Lake and 1 more	4 hr
Jul 23, 2:03 AM CDT	Dense Fog Advisory	PAH	Edwards, Franklin, Gallatin, Hamilton, Hardin, Jefferson and 8 more	6 hr
Aug 2, 6:11 AM CDT	Dense Fog Advisory	ILX	Clark, Clay, Coles, Crawford, Cumberland, Effingham and 3 more	3 hr
Aug 17, 6:07 AM CDT	Dense Fog Advisory	PAH	Edwards, Jefferson, Perry, Wabash, Wayne	104 min
Aug 17, 6:08 AM CDT	Dense Fog Advisory	LSX	Bond, Clinton, Fayette, Macoupin, Madison, Marion and 2 more	3 hr
Aug 18, 3:24 AM CDT	Dense Fog Advisory	ILX	Clark, Clay, Crawford, Cumberland, Effingham, Jasper and 2 more	6 hr
Aug 18, 4:58 AM CDT	Dense Fog Advisory	LSX	Bond, Clinton, Fayette, Madison, Marion, Montgomery and 2 more	4 hr
Aug 31, 5:09 AM CDT	Dense Fog Advisory	LSX	Bond, Calhoun, Clinton, Fayette, Greene, Jersey and 8 more	4 hr
Sep 9, 2:15 AM CDT	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Clark, Coles, Cumberland and 21 more	7 hr
Sep 9, 3:05 AM CDT	Dense Fog Advisory	LOT	Ford, Grundy, Iroquois, Kankakee, LaSalle, Livingston	6 hr
Sep 19, 2:33 AM CDT	Dense Fog Advisory	ILX	Clark, Clay, Crawford, Cumberland, Effingham, Jasper and 2 more	6 hr
Sep 19, 2:38 AM CDT	Dense Fog Advisory	PAH	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	6 hr
Sep 19, 2:44 AM CDT	Dense Fog Advisory	LSX	Bond, Clinton, Fayette, Madison, Marion, Monroe and 3 more	6 hr
Sep 20, 4:52 AM CDT	Dense Fog Advisory	LOT	Boone, DeKalb, Lake, Lee, McHenry, Ogle and 1 more	4 hr
Sep 20, 5:16 AM CDT	Dense Fog Advisory	DVN	Carroll, Jo Daviess, Stephenson	4 hr
Oct 3, 3:01 AM CDT	Dense Fog Advisory	ILX	Christian, Clark, Clay, Crawford, Cumberland, Effingham and 6 more	7 hr
Oct 3, 3:39 AM CDT	Dense Fog Advisory	LSX	Bond, Clinton, Fayette, Macoupin, Marion, Montgomery	5 hr
Oct 3, 4:06 AM CDT	Dense Fog Advisory	PAH	Alexander, Edwards, Gallatin, Hamilton, Hardin, Jefferson and 10 more	5 hr
Nov 3, 5:45 AM CDT	Dense Fog Advisory	LOT	Boone, DeKalb, Kane, Lee, McHenry, Ogle and 1 more	4 hr
Nov 4, 3:38 AM CDT	Dense Fog Advisory	LOT	Boone, DeKalb, Grundy, Kane, Kendall, LaSalle and 4 more	7 hr
Nov 4, 3:48 AM CDT	Dense Fog Advisory	DVN	Bureau, Carroll, Henry, Jo Daviess, Mercer, Putnam and 4 more	8 hr
Nov 27, 9:09 AM CST	Dense Fog Advisory	ILX	Champaign, Christian, Coles, DeWitt, Douglas, Edgar and 17 more	3 hr
Nov 27, 9:21 AM CST	Dense Fog Advisory	LOT	Boone, DeKalb, Ford, Grundy, Iroquois, Kane and 8 more	4 hr
Dec 5, 3:47 AM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Hancock, Henderson, Henry, Jo Daviess and 7 more	9 hr
Dec 5, 3:59 AM CST	Dense Fog Advisory	LSX	Adams, Brown, Pike	8 hr
Dec 5, 4:01 AM CST	Dense Fog Advisory	ILX	Cass, Fulton, Knox, Mason, Menard, Morgan and 3 more	8 hr
Dec 5, 9:10 AM CST	Dense Fog Advisory	LOT	Boone, DeKalb, Grundy, Kane, Kendall, LaSalle and 4 more	4 hr
Dec 6, 5:46 AM CST	Dense Fog Advisory	LOT	Boone, DeKalb, DuPage, Grundy, Kane, Kendall and 5 more	5 hr
Dec 6, 6:03 AM CST	Dense Fog Advisory	DVN	Bureau, Carroll, Henry, Jo Daviess, Mercer, Putnam and 3 more	5 hr
Dec 24, 6:17 AM CST	Dense Fog Advisory	PAH	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	4 hr
Dec 24, 6:26 AM CST	Dense Fog Advisory	ILX	Champaign, Clark, Clay, Coles, Crawford, Cumberland and 13 more	4 hr
Dec 24, 3:52 PM CST	Dense Fog Advisory	PAH	Alexander, Edwards, Franklin, Gallatin, Hamilton, Hardin and 13 more	18 hr
Dec 25, 4:32 PM CST	Dense Fog Advisory	PAH	Edwards, Franklin, Hamilton, Jefferson, Perry, Wabash and 2 more	5 hr
Dec 25, 5:33 PM CST	Dense Fog Advisory	LSX	Adams, Bond, Brown, Calhoun, Clinton, Fayette and 9 more	5 hr
Dec 25, 5:47 PM CST	Dense Fog Advisory	ILX	Cass, Champaign, Christian, Clark, Clay, Coles and 18 more	7 hr

By county

Every county with at least one alert. A county page lists each alert that covered it.

60 more counties

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force now Tornadoes on record The radar archive 2015 2017

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.