Alert archive / Illinois / Iroquois County
Weather alerts in Iroquois County, Illinois, 2009
121 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Iroquois County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 121
- Warnings
- 39
- Watches
- 24
- Advisories
- 33
- Busiest month
- May22 alerts
- Busiest day
- May 14, 20099 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
0 of 3 tornado warnings covering Iroquois County in 2009 had a tornado report inside them; 0 of 2 tornado reports fell inside a warning.
Iroquois County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 3 | 0 | 100% | 2 | 0% | |
| Severe thunderstorm warnings | 19 | 9 | 53% | 7 | 86% | 55 min |
| Flash flood warnings | 5 | 3 | 40% | 1 | 0% |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Chicago, IL: tornado warnings | 12 | 3 | 75% | 11 | 73% | 11 min |
| NWS Chicago, IL: severe thunderstorm warnings | 97 | 47 | 52% | 183 | 68% | 26 min |
| NWS Chicago, IL: flash flood warnings | 25 | 10 | 60% | 31 | 87% | 80 min |
An office's figures cover every county it serves, including across state lines.
Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.
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 1, 2:26 PM CST | River Flood Warning | LOT | 21 hr |
| Jan 3, 9:25 PM CST | Dense Fog Advisory | LOT | 8 hr |
| Jan 6, 3:43 AM CST | Freezing Rain Advisory | LOT | 14 hr |
| Jan 8, 2:53 PM CST | Winter Weather Advisory | LOT | 51 hr |
| Jan 9, 10:05 AM CST | Areal Flood Advisory | LOT | 294 days |
| Jan 9, 11:53 PM CST | Mesoscale Discussion | SPC | 6 hr |
| Jan 11, 11:07 AM CST | Areal Flood Advisory | LOT | 292 days |
| Jan 12, 4:21 AM CST | Winter Weather Advisory | LOT | 28 hr |
| Jan 12, 3:40 PM CST | Blizzard Watch | LOT | 19 hr |
| Jan 13, 2:07 PM CST | Wind Chill Watch | LOT | 13 hr |
| Jan 13, 3:02 PM CST | Winter Weather Advisory | LOT | 33 hr |
| Jan 13, 11:38 PM CST | Mesoscale Discussion | SPC | 4 hr |
| Jan 14, 3:23 AM CST | Wind Chill Warning | LOT | 57 hr |
| Jan 16, 8:56 AM CST | Areal Flood Advisory | LOT | 137 days |
| Jan 16, 3:08 PM CST | Wind Chill Advisory | LOT | 9 hr |
| Feb 10, 4:00 AM CST | Flood Watch | LOT | 41 hr |
| Feb 11, 3:40 AM CST | Wind Advisory | LOT | 18 hr |
| Feb 11, 9:23 AM CST | River Flood Warning | LOT | 24 hr |
| Feb 20, 3:41 AM CST | Winter Weather Advisory | LOT | 41 hr |
| Feb 26, 3:50 AM CST | Dense Fog Advisory | LOT | 11 hr |
| Mar 6, 3:28 PM CST | Flash Flood Watch | LOT | 48 hr |
| Mar 8, 9:13 AM CDT | Wind Advisory | LOT | 12 hr |
| Mar 8, 10:39 AM CDT | Tornado Watch | SPC | 7 hr |
| Mar 8, 1:06 PM CDT | Severe Thunderstorm Warning | LOT | 39 min |
| Mar 8, 1:30 PM CDT | River Flood Warning | LOT | 11 days |
| Mar 8, 1:54 PM CDT | Severe Thunderstorm Warning | LOT | 51 min |
| Mar 8, 4:36 PM CDT | High Wind Warning | LOT | 2 hr |
| Mar 9, 3:39 AM CDT | Flash Flood Watch | LOT | 24 hr |
| Mar 10, 2:03 AM CDT | Areal Flood Warning | LOT | 36 hr |
| Mar 10, 3:37 AM CDT | Wind Advisory | LOT | 27 hr |
| Mar 10, 9:43 PM CDT | Flash Flood Warning | LOT | 8 hr |
| Mar 11, 10:09 AM CDT | River Flood Warning | LOT | 4 days |
| Mar 24, 4:08 AM CDT | Wind Advisory | LOT | 16 hr |
| Apr 5, 10:50 AM CDT | Mesoscale Discussion | SPC | 115 min |
| Apr 6, 9:43 AM CDT | River Flood Warning | LOT | 35 hr |
| Apr 26, 12:13 PM CDT | Areal Flood Advisory | LOT | 54 days |
| Apr 26, 2:17 PM CDT | Wind Advisory | LOT | 5 hr |
| Apr 27, 3:55 AM CDT | Wind Advisory | LOT | 10 hr |
| Apr 28, 12:44 AM CDT | Areal Flood Advisory | LOT | 55 days |
| Apr 29, 3:10 PM CDT | Flash Flood Watch | LOT | 20 hr |
| May 8, 8:35 PM CDT | Mesoscale Discussion | SPC | 85 min |
| May 13, 5:47 PM CDT | Mesoscale Discussion | SPC | 88 min |
| May 13, 6:02 PM CDT | Tornado Watch | SPC | 5 hr |
| May 13, 8:35 PM CDT | Mesoscale Discussion | SPC | 85 min |
| May 13, 10:17 PM CDT | Mesoscale Discussion | SPC | 58 min |
| May 13, 10:51 PM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| May 13, 11:13 PM CDT | Severe Thunderstorm Warning | LOT | 62 min |
| May 14, 12:02 AM CDT | Flash Flood Warning | LOT | 4 hr |
| May 14, 12:15 AM CDT | Severe Thunderstorm Warning | LOT | 43 min |
| May 14, 4:10 AM CDT | Areal Flood Warning | LOT | 3 hr |
| May 14, 5:33 AM CDT | River Flood Watch | LOT | 5 hr |
| May 14, 3:34 PM CDT | Flash Flood Watch | LOT | 30 hr |
| May 15, 11:05 AM CDT | River Flood Warning | LOT | 5 days |
| May 15, 2:05 PM CDT | Mesoscale Discussion | SPC | 25 min |
| May 15, 2:39 PM CDT | Tornado Watch | SPC | 7 hr |
| May 15, 5:31 PM CDT | Mesoscale Discussion | SPC | 119 min |
| May 15, 5:46 PM CDT | Flash Flood Warning | LOT | 6 hr |
| May 15, 6:09 PM CDT | Severe Thunderstorm Warning | LOT | 66 min |
| May 15, 8:07 PM CDT | Flash Flood Warning | LOT | 6 hr |
| May 15, 11:16 PM CDT | Areal Flood Warning | LOT | 12 hr |
| May 29, 3:17 PM CDT | Mesoscale Discussion | SPC | 88 min |
| May 30, 6:01 PM CDT | Mesoscale Discussion | SPC | 59 min |
| Jun 1, 1:31 PM CDT | Mesoscale Discussion | SPC | 59 min |
| Jun 1, 2:37 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 1, 6:00 PM CDT | Severe Thunderstorm Warning | LOT | 60 min |
| Jun 1, 6:34 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Jun 1, 7:29 PM CDT | Severe Thunderstorm Warning | LOT | 24 min |
| Jun 1, 8:57 PM CDT | Mesoscale Discussion | SPC | 63 min |
| Jun 8, 11:54 AM CDT | Mesoscale Discussion | SPC | 96 min |
| Jun 8, 3:53 PM CDT | Mesoscale Discussion | SPC | 67 min |
| Jun 19, 7:14 AM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 19, 1:08 PM CDT | Flash Flood Watch | LOT | 8 hr |
| Jun 19, 2:24 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 19, 5:37 PM CDT | Mesoscale Discussion | SPC | 53 min |
| Jun 19, 6:00 PM CDT | Severe Thunderstorm Warning | LOT | 32 min |
| Jun 19, 6:16 PM CDT | Tornado Warning | LOT | 35 min |
| Jun 19, 6:23 PM CDT | Severe Thunderstorm Warning | LOT | 52 min |
| Jun 19, 6:56 PM CDT | Severe Thunderstorm Warning | LOT | 94 min |
| Jun 19, 7:59 PM CDT | Mesoscale Discussion | SPC | 91 min |
| Jun 22, 4:31 AM CDT | Severe Thunderstorm Warning | LOT | 59 min |
| Jun 22, 3:15 PM CDT | Heat Advisory | LOT | 52 hr |
| Jun 25, 10:18 AM CDT | Heat Advisory | LOT | 9 hr |
| Jun 25, 3:57 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Jun 27, 2:41 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 16, 9:52 PM CDT | Severe Thunderstorm Warning | LOT | 31 min |
| Jul 24, 11:00 PM CDT | Severe Thunderstorm Watch | SPC | 3 hr |
| Jul 24, 11:16 PM CDT | Severe Thunderstorm Warning | LOT | 59 min |
| Jul 24, 11:46 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Jul 28, 4:07 PM CDT | Flash Flood Warning | LOT | 8 hr |
| Jul 28, 4:51 PM CDT | Special Weather Statement | LOT | 54 min |
| Jul 28, 5:17 PM CDT | Special Weather Statement | LOT | 43 min |
| Jul 28, 6:15 PM CDT | Special Weather Statement | LOT | 30 min |
| Aug 4, 4:29 AM CDT | Dense Fog Advisory | LOT | 4 hr |
| Aug 4, 7:39 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Aug 4, 9:14 AM CDT | Severe Thunderstorm Warning | LOT | 76 min |
| Aug 4, 10:11 AM CDT | Severe Thunderstorm Warning | LOT | 64 min |
| Aug 8, 4:07 AM CDT | Heat Advisory | LOT | 38 hr |
| Aug 17, 5:52 PM CDT | Severe Thunderstorm Warning | LOT | 53 min |
| Aug 17, 6:48 PM CDT | Areal Flood Advisory | LOT | 4 hr |
| Aug 19, 12:49 PM CDT | Tornado Watch | SPC | 6 hr |
| Aug 19, 3:19 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Aug 19, 4:37 PM CDT | Severe Thunderstorm Warning | LOT | 53 min |
| Aug 19, 5:08 PM CDT | Severe Thunderstorm Warning | LOT | 57 min |
| Aug 19, 5:19 PM CDT | Tornado Warning | LOT | 29 min |
| Aug 19, 6:11 PM CDT | Tornado Warning | LOT | 32 min |
| Sep 9, 9:19 PM CDT | Dense Fog Advisory | LOT | 12 hr |
| Sep 10, 8:44 PM CDT | Dense Fog Advisory | LOT | 11 hr |
| Sep 12, 4:08 AM CDT | Dense Fog Advisory | LOT | 5 hr |
| Sep 12, 9:43 PM CDT | Dense Fog Advisory | LOT | 11 hr |
| Sep 27, 5:55 AM CDT | Dense Fog Advisory | LOT | 4 hr |
| Sep 27, 5:32 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Sep 27, 8:22 PM CDT | Tornado Watch | SPC | 3 hr |
| Sep 27, 10:26 PM CDT | Severe Thunderstorm Warning | LOT | 49 min |
| Sep 27, 11:04 PM CDT | Mesoscale Discussion | SPC | 86 min |
| Oct 9, 4:00 PM CDT | Freeze Warning | LOT | 41 hr |
| Oct 29, 3:13 PM CDT | Flood Watch | LOT | 24 hr |
| Nov 23, 9:40 PM CST | Dense Fog Advisory | LOT | 11 hr |
| Dec 9, 4:47 AM CST | Wind Advisory | LOT | 13 hr |
| Dec 22, 3:35 PM CST | Winter Weather Advisory | LOT | 29 hr |
| Dec 23, 3:45 AM CST | Flood Watch | LOT | 55 hr |
| Dec 27, 4:29 AM CST | Winter Weather Advisory | LOT | 10 hr |
By product
Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20082010
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.