Alert archive / Illinois / McHenry County

Weather alerts in McHenry County, Illinois, 2026

129 weather alerts in 2026, 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 2026. Tap one for its archive.

Alerts
129
Warnings
39
Watches
28
Advisories
31
Busiest month
April35 alerts
Busiest day
April 18, 202610 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.

IssuedProductOfficeLasted
Jan 7, 7:15 AM CSTDense Fog AdvisoryLOT5 hr
Jan 18, 2:13 AM CSTCold Weather AdvisoryLOT34 hr
Jan 20, 4:00 AM CSTWinter Weather AdvisoryLOT23 hr
Jan 21, 3:01 AM CSTExtreme Cold WatchLOT24 hr
Jan 22, 3:12 AM CSTCold Weather AdvisoryLOT55 hr
Jan 22, 3:12 AM CSTExtreme Cold WarningLOT33 hr
Jan 25, 2:35 AM CSTCold Weather AdvisoryLOT32 hr
Feb 17, 1:45 PM CSTFire Weather WatchLOT11 hr
Feb 18, 1:00 AM CSTRed Flag WarningLOT17 hr
Feb 18, 1:02 AM CSTWind AdvisoryLOT17 hr
Feb 19, 1:56 PM CSTWind AdvisoryLOT26 hr
Mar 4, 1:39 AM CSTDense Fog AdvisoryLOT7 hr
Mar 4, 8:34 PM CSTDense Fog AdvisoryLOT37 hr
Mar 10, 2:41 AM CDTDense Fog AdvisoryLOT8 hr
Mar 10, 4:53 PM CDTMesoscale DiscussionSPC97 min
Mar 10, 5:40 PM CDTSevere Thunderstorm WatchSPC7 hr
Mar 10, 7:21 PM CDTMesoscale DiscussionSPC84 min
Mar 12, 1:33 AM CDTHigh Wind WatchLOT10 hr
Mar 12, 1:33 AM CDTWind AdvisoryLOT40 hr
Mar 12, 11:28 AM CDTHigh Wind WarningLOT29 hr
Mar 15, 9:27 AM CDTWinter Weather AdvisoryLOT39 hr
Mar 15, 6:51 PM CDTBlizzard WarningLOT16 hr
Mar 30, 8:57 PM CDTMesoscale DiscussionSPC2 hr
Mar 30, 9:21 PM CDTSevere Thunderstorm WatchSPC6 hr
Mar 30, 10:42 PM CDTSevere Thunderstorm WarningLOT26 min
Mar 30, 11:29 PM CDTMesoscale DiscussionSPC2 hr
Mar 31, 1:54 AM CDTMesoscale DiscussionSPC96 min
Apr 2, 1:43 PM CDTTornado WatchSPC8 hr
Apr 2, 7:00 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT60 min
Apr 2, 7:01 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT59 min
Apr 2, 7:40 PM CDTTornado WarningLOT35 min
Apr 2, 8:01 PM CDTAreal Flood AdvisoryLOT3 hr
Apr 3, 3:56 PM CDTFlood WatchLOT18 hr
Apr 5, 9:01 PM CDTRiver Flood WatchLOT23 hr
Apr 6, 8:26 PM CDTRiver Flood WarningLOT28 days
Apr 14, 2:33 PM CDTTornado WatchSPC9 hr
Apr 14, 7:11 PM CDTFlood WatchLOT30 hr
Apr 14, 8:12 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT78 min
Apr 14, 8:32 PM CDTMesoscale DiscussionSPC88 min
Apr 14, 9:28 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT62 min
Apr 15, 2:48 AM CDTSevere Thunderstorm WarningLOT42 min
Apr 15, 4:49 PM CDTMesoscale DiscussionSPC86 min
Apr 15, 7:55 PM CDTSevere Thunderstorm WatchSPC4 hr
Apr 15, 9:26 PM CDTMesoscale DiscussionSPC94 min
Apr 16, 7:01 PM CDTDense Fog AdvisoryLOT15 hr
Apr 17, 11:48 AM CDTFlood WatchLOT15 hr
Apr 17, 12:40 PM CDTTornado WatchSPC9 hr
Apr 17, 4:42 PM CDTMesoscale DiscussionSPC2 hr
Apr 17, 7:16 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT74 min
Apr 17, 7:28 PM CDTTornado WarningLOT47 min
Apr 17, 8:09 PM CDTMesoscale DiscussionSPC2 hr
Apr 17, 8:12 PM CDTFlash Flood WarningLOT6 hr
Apr 17, 8:29 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT31 min
Apr 17, 8:36 PM CDTTornado WarningLOT39 min
Apr 18, 1:54 AM CDTAreal Flood WarningLOT6 hr
Apr 18, 1:29 PM CDTFrost AdvisoryLOT20 hr
Apr 18, 1:29 PM CDTFreeze WatchLOT12 hr
Apr 18, 2:20 PM CDTAreal Flood WarningLOT13 days
Apr 19, 1:52 AM CDTFreeze WarningLOT30 hr
Apr 21, 1:07 PM CDTMesoscale DiscussionSPC113 min
Apr 27, 11:18 AM CDTWind AdvisoryLOT5 hr
Apr 27, 12:50 PM CDTHigh Wind WarningLOT3 hr
May 1, 3:32 AM CDTFrost AdvisoryLOT28 hr
May 4, 3:42 PM CDTMesoscale DiscussionSPC2 hr
May 6, 1:23 PM CDTFrost AdvisoryLOT19 hr
May 15, 10:33 PM CDTSevere Thunderstorm WatchSPC4 hr
May 16, 12:29 AM CDTMesoscale DiscussionSPC91 min
Jun 10, 12:00 PM CDTSevere Thunderstorm WatchSPC9 hr
Jun 10, 1:00 PM CDTMesoscale DiscussionSPC2 hr
Jun 10, 2:09 PM CDTSevere Thunderstorm Warning Considerable damage threatLOT66 min
Jun 10, 2:50 PM CDTSevere Thunderstorm WarningLOT55 min
Jun 11, 10:05 AM CDTFlood WatchLOT11 hr
Jun 11, 1:57 PM CDTTornado WatchSPC7 hr
Jun 11, 5:39 PM CDTSevere Thunderstorm WarningLOT51 min
Jun 11, 6:10 PM CDTSevere Thunderstorm WarningLOT65 min
Jun 11, 6:14 PM CDTMesoscale DiscussionSPC91 min
Jun 11, 6:27 PM CDTFlash Flood WarningLOT3 hr
Jun 11, 9:06 PM CDTAreal Flood AdvisoryLOT22 hr
Jun 17, 2:20 AM CDTFlood WatchLOT15 hr
Jun 17, 9:17 AM CDTWind AdvisoryLOT5 hr
Jun 17, 8:31 PM CDTSevere Thunderstorm WarningLOT44 min
Jun 24, 12:44 PM CDTMesoscale DiscussionSPC3 hr
Jun 24, 1:55 PM CDTSevere Thunderstorm WatchSPC8 hr
Jun 24, 4:54 PM CDTSevere Thunderstorm WarningLOT51 min
Jun 24, 5:28 PM CDTMesoscale DiscussionSPC92 min
Jun 24, 5:35 PM CDTSevere Thunderstorm WarningLOT55 min
Jun 24, 8:06 PM CDTMesoscale DiscussionSPC84 min
Jun 28, 2:47 AM CDTHeat AdvisoryLOT47 hr
Jun 28, 11:18 AM CDTExtreme Heat WarningLOT5 days
Jun 28, 4:41 PM CDTWind AdvisoryLOT108 min
Jul 1, 2:34 PM CDTMesoscale DiscussionSPC116 min
Jul 2, 2:30 PM CDTMesoscale DiscussionSPC90 min
Jul 2, 7:40 PM CDTMesoscale DiscussionSPC2 hr
Jul 3, 11:15 AM CDTMesoscale DiscussionSPC2 hr
Jul 3, 11:52 AM CDTSevere Thunderstorm WatchSPC6 hr
Jul 3, 5:05 PM CDTMesoscale DiscussionSPC115 min
Jul 3, 6:37 PM CDTSevere Thunderstorm WatchSPC6 hr
Jul 3, 7:33 PM CDTSevere Thunderstorm WarningLOT30 min
Jul 3, 8:33 PM CDTMesoscale DiscussionSPC117 min
Jul 4, 1:53 PM CDTSevere Thunderstorm WarningLOT40 min
Jul 27, 2:10 AM CDTHeat AdvisoryLOT14 hr
Jul 27, 2:10 AM CDTExtreme Heat WarningLOT19 hr
Jul 27, 3:02 AM CDTDense Fog AdvisoryLOT5 hr
Jul 27, 9:40 AM CDTMesoscale DiscussionSPC3 hr
Jul 27, 10:57 AM CDTSevere Thunderstorm WarningLOT78 min
Jul 27, 11:25 AM CDTSevere Thunderstorm Warning Considerable damage threatLOT80 min
Aug 9, 9:20 AM CDTMesoscale DiscussionSPC85 min
Aug 9, 9:46 AM CDTSevere Thunderstorm WatchSPC6 hr
Aug 9, 12:43 PM CDTAreal Flood AdvisoryLOT3 hr
Aug 9, 5:03 PM CDTFlood WatchLOT10 hr
Aug 9, 8:14 PM CDTMesoscale DiscussionSPC2 hr
Aug 9, 8:43 PM CDTSevere Thunderstorm WatchSPC7 hr
Aug 10, 12:47 PM CDTMesoscale DiscussionSPC2 hr
Aug 11, 3:11 AM CDTSevere Thunderstorm WarningLOT51 min
Aug 11, 3:49 AM CDTSevere Thunderstorm WarningLOT27 min
Aug 11, 7:22 AM CDTSevere Thunderstorm WatchSPC6 hr
Aug 11, 9:00 AM CDTMesoscale DiscussionSPC2 hr
Aug 11, 9:38 AM CDTSevere Thunderstorm Warning Considerable damage threatLOT67 min
Aug 18, 5:29 PM CDTMesoscale DiscussionSPC2 hr
Aug 21, 2:17 PM CDTSevere Thunderstorm WarningLOT43 min
Aug 21, 2:57 PM CDTSevere Thunderstorm WatchSPC9 hr
Aug 31, 12:24 PM CDTHeat AdvisoryLOT33 hr
Aug 31, 12:24 PM CDTHeat AdvisoryLOT3 days
Sep 3, 7:56 PM CDTHeat AdvisoryLOT25 hr
Sep 4, 9:01 PM CDTMesoscale DiscussionSPC3 hr
Sep 10, 3:11 AM CDTDense Fog AdvisoryLOT5 hr
Sep 18, 1:47 PM CDTFlood WatchLOT47 hr
Sep 19, 3:29 AM CDTAreal Flood AdvisoryLOT8 hr
Sep 20, 4:30 AM CDTAreal Flood AdvisoryLOT4 hr

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

ProductAlerts
Severe storms
Severe Thunderstorm Warning23
Tornado Warning3
Severe Thunderstorm Watch12
Tornado Watch4
Mesoscale Discussion31
Flooding
Areal Flood Warning2
Flash Flood Warning2
River Flood Warning1
Flood Watch7
River Flood Watch1
Areal Flood Advisory5
Winter
Blizzard Warning1
Winter Weather Advisory2
Heat
Extreme Heat Warning2
Heat Advisory5
Cold
Extreme Cold Warning1
Freeze Warning1
Extreme Cold Watch1
Freeze Watch1
Cold Weather Advisory3
Frost Advisory3
Wind and dust
High Wind Warning2
High Wind Watch1
Wind Advisory6
Fire
Red Flag Warning1
Fire Weather Watch1
Fog and smoke
Dense Fog Advisory7

The busiest days

Days with the most alerts issued, by UTC date.

  1. April 18, 202610alerts
  2. April 15, 20266alerts
  3. June 11, 20266alerts
  4. July 27, 20266alerts
  5. March 31, 20265alerts
  6. April 3, 20265alerts
  7. June 24, 20265alerts
  8. July 3, 20265alerts
  9. August 11, 20265alerts
  10. April 17, 20264alerts

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.