Alert archive / Iowa / Jefferson County
Weather alerts in Jefferson County, Iowa, 2018
124 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Jefferson County and its neighbors
Each county as a circle sized by its count in 2018. Tap one for its archive.
- Alerts
- 124
- Warnings
- 18
- Watches
- 15
- Advisories
- 32
- Busiest month
- June20 alerts
- Busiest day
- September 2, 20189 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 1 tornado warnings covering Jefferson County in 2018 had a tornado report inside them.
Jefferson County, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 1 | 0 | 100% | 0 | ||
| Severe thunderstorm warnings | 11 | 6 | 45% | 1 | 100% | 10 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2018
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Quad Cities, IA: tornado warnings | 47 | 14 | 70% | 32 | 59% | 8 min |
| NWS Quad Cities, IA: severe thunderstorm warnings | 136 | 92 | 32% | 249 | 75% | 22 min |
| NWS Quad Cities, IA: flash flood warnings | 29 | 19 | 34% | 39 | 79% | 73 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 2, 2:50 PM CST | Wind Chill Advisory | DVN | 43 hr |
| Jan 2, 9:18 PM CST | Special Weather Statement | DVN | 117 min |
| Jan 2, 11:20 PM CST | Special Weather Statement | DVN | 115 min |
| Jan 6, 2:45 AM CST | Winter Weather Advisory | DVN | 45 hr |
| Jan 6, 2:50 AM CST | Wind Chill Advisory | DVN | 6 hr |
| Jan 11, 3:07 AM CST | Winter Weather Advisory | DVN | 17 hr |
| Jan 11, 9:36 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Jan 14, 2:45 PM CST | Wind Chill Advisory | DVN | 44 hr |
| Jan 14, 2:45 PM CST | Winter Weather Advisory | DVN | 21 hr |
| Jan 14, 8:19 PM CST | Special Weather Statement | DVN | 86 min |
| Feb 4, 1:53 PM CST | Winter Weather Advisory | DVN | 32 hr |
| Feb 5, 11:36 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Feb 8, 2:59 AM CST | Winter Weather Advisory | DVN | 39 hr |
| Feb 9, 9:43 AM CST | Special Weather Statement | DVN | 2 hr |
| Feb 9, 3:09 PM CST | Winter Weather Advisory | DVN | 18 hr |
| Feb 10, 3:14 PM CST | Winter Weather Advisory | DVN | 18 hr |
| Feb 20, 9:37 AM CST | Flood Watch | DVN | 6 hr |
| Feb 21, 3:47 PM CST | Winter Weather Advisory | DVN | 20 hr |
| Feb 23, 3:13 PM CST | Winter Weather Advisory | DVN | 20 hr |
| Mar 5, 1:48 AM CST | Special Weather Statement | DVN | 87 min |
| Mar 5, 3:16 AM CST | Special Weather Statement | DVN | 89 min |
| Mar 5, 7:15 AM CST | Special Weather Statement | DVN | 90 min |
| Mar 16, 3:10 AM CDT | Winter Weather Advisory | DVN | 32 hr |
| Mar 16, 5:16 PM CDT | Special Weather Statement | DVN | 59 min |
| Mar 16, 6:18 PM CDT | Special Weather Statement | DVN | 57 min |
| Mar 16, 7:35 PM CDT | Special Weather Statement | DVN | 55 min |
| Mar 16, 9:37 PM CDT | Special Weather Statement | DVN | 53 min |
| Mar 18, 2:25 AM CDT | Dense Fog Advisory | DVN | 9 hr |
| Mar 24, 5:40 PM CDT | Special Weather Statement | DVN | 80 min |
| Mar 24, 6:53 PM CDT | Special Weather Statement | DVN | 67 min |
| Apr 7, 3:08 PM CDT | Winter Weather Advisory | DVN | 43 hr |
| Apr 9, 10:03 AM CDT | Winter Weather Advisory | DVN | 94 min |
| Apr 14, 3:51 AM CDT | Winter Weather Advisory | DVN | 39 hr |
| Apr 27, 2:50 PM CDT | Red Flag Warning | DVN | 5 hr |
| May 2, 1:33 PM CDT | Mesoscale Discussion | SPC | 117 min |
| May 2, 3:56 PM CDT | Severe Thunderstorm Watch | SPC | 9 hr |
| May 2, 4:27 PM CDT | Special Weather Statement | DVN | 33 min |
| May 2, 7:21 PM CDT | Mesoscale Discussion | SPC | 84 min |
| May 2, 10:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| May 14, 11:31 PM CDT | Special Weather Statement | DVN | 44 min |
| May 22, 3:34 AM CDT | Dense Fog Advisory | DVN | 5 hr |
| May 25, 11:31 PM CDT | Special Weather Statement | DVN | 29 min |
| May 26, 2:06 AM CDT | Special Weather Statement | DVN | 24 min |
| Jun 8, 12:51 PM CDT | Mesoscale Discussion | SPC | 114 min |
| Jun 8, 2:05 PM CDT | Severe Thunderstorm Warning | DVN | 26 min |
| Jun 12, 12:28 AM CDT | Special Weather Statement | DVN | 62 min |
| Jun 14, 8:53 AM CDT | Special Weather Statement | DVN | 52 min |
| Jun 14, 10:01 AM CDT | Special Weather Statement | DVN | 59 min |
| Jun 14, 11:53 AM CDT | Special Weather Statement | DVN | 67 min |
| Jun 14, 12:31 PM CDT | Severe Thunderstorm Warning | DVN | 59 min |
| Jun 15, 3:25 AM CDT | Heat Advisory | DVN | 4 days |
| Jun 20, 6:36 AM CDT | Special Weather Statement | DVN | 24 min |
| Jun 20, 2:14 PM CDT | Special Weather Statement | DVN | 61 min |
| Jun 20, 3:04 PM CDT | Tornado Watch | SPC | 4 hr |
| Jun 20, 5:13 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 20, 6:21 PM CDT | Special Weather Statement | DVN | 54 min |
| Jun 27, 3:11 PM CDT | Heat Advisory | DVN | 24 hr |
| Jun 28, 10:57 AM CDT | Mesoscale Discussion | SPC | 2 hr |
| Jun 28, 12:57 PM CDT | Special Weather Statement | DVN | 18 min |
| Jun 28, 1:04 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 28, 1:12 PM CDT | Severe Thunderstorm Warning | DVN | 63 min |
| Jun 28, 1:54 PM CDT | Severe Thunderstorm Warning | DVN | 66 min |
| Jun 28, 3:31 PM CDT | Excessive Heat Warning | DVN | 54 hr |
| Jul 3, 3:48 PM CDT | Heat Advisory | DVN | 28 hr |
| Jul 13, 3:37 AM CDT | Heat Advisory | DVN | 15 hr |
| Jul 13, 2:15 PM CDT | Special Weather Statement | DVN | 60 min |
| Jul 13, 2:35 PM CDT | Special Weather Statement | DVN | 40 min |
| Jul 13, 3:21 PM CDT | Special Weather Statement | DVN | 54 min |
| Jul 15, 12:50 PM CDT | Special Weather Statement | DVN | 70 min |
| Jul 15, 2:00 PM CDT | Special Weather Statement | DVN | 90 min |
| Jul 19, 3:11 PM CDT | Tornado Watch | SPC | 6 hr |
| Jul 19, 5:18 PM CDT | Mesoscale Discussion | SPC | 57 min |
| Jul 19, 5:26 PM CDT | Tornado Warning | DVN | 49 min |
| Aug 6, 10:00 PM CDT | Special Weather Statement | DVN | 45 min |
| Aug 6, 10:11 PM CDT | Severe Thunderstorm Warning | DVN | 37 min |
| Aug 16, 3:00 AM CDT | Dense Fog Advisory | DVN | 6 hr |
| Aug 16, 3:56 PM CDT | Special Weather Statement | DVN | 79 min |
| Aug 25, 1:41 PM CDT | Heat Advisory | DVN | 5 hr |
| Aug 26, 3:03 AM CDT | Heat Advisory | DVN | 64 hr |
| Aug 28, 9:08 AM CDT | Flash Flood Watch | DVN | 20 hr |
| Aug 28, 4:45 PM CDT | Mesoscale Discussion | SPC | 60 min |
| Aug 28, 5:06 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 28, 5:51 PM CDT | Severe Thunderstorm Warning | DVN | 39 min |
| Aug 31, 7:12 PM CDT | Special Weather Statement | DVN | 108 min |
| Sep 1, 3:44 AM CDT | Flash Flood Watch | DVN | 24 hr |
| Sep 1, 6:34 PM CDT | Mesoscale Discussion | SPC | 56 min |
| Sep 1, 8:14 PM CDT | Severe Thunderstorm Warning | DVN | 46 min |
| Sep 1, 8:20 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Sep 1, 9:05 PM CDT | Severe Thunderstorm Warning | DVN | 40 min |
| Sep 1, 9:08 PM CDT | Severe Thunderstorm Warning | DVN | 52 min |
| Sep 1, 9:22 PM CDT | Severe Thunderstorm Warning | DVN | 38 min |
| Sep 1, 10:27 PM CDT | Mesoscale Discussion | SPC | 63 min |
| Sep 2, 9:26 AM CDT | Flash Flood Watch | DVN | 39 hr |
| Sep 2, 2:24 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 2, 6:48 PM CDT | Special Weather Statement | DVN | 42 min |
| Sep 2, 7:34 PM CDT | Special Weather Statement | DVN | 56 min |
| Sep 3, 1:20 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 4, 3:56 AM CDT | Flash Flood Watch | DVN | 39 hr |
| Sep 6, 2:38 PM CDT | Flash Flood Watch | DVN | 36 hr |
| Sep 19, 1:23 AM CDT | Special Weather Statement | DVN | 22 min |
| Sep 19, 1:47 AM CDT | Special Weather Statement | DVN | 58 min |
| Sep 25, 1:07 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Sep 25, 1:17 PM CDT | Severe Thunderstorm Warning | DVN | 43 min |
| Oct 5, 2:22 PM CDT | Special Weather Statement | DVN | 38 min |
| Oct 5, 2:39 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 7, 2:44 PM CDT | Flash Flood Watch | DVN | 70 hr |
| Oct 8, 2:30 AM CDT | Special Weather Statement | DVN | 60 min |
| Oct 9, 12:59 PM CDT | Mesoscale Discussion | SPC | 3 hr |
| Oct 9, 1:46 PM CDT | Tornado Watch | SPC | 7 hr |
| Oct 9, 3:53 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Oct 11, 3:40 AM CDT | Frost Advisory | DVN | 28 hr |
| Oct 14, 3:21 PM CDT | Freeze Warning | DVN | 18 hr |
| Oct 15, 3:14 AM CDT | Freeze Warning | DVN | 30 hr |
| Oct 19, 7:36 PM CDT | Wind Advisory | DVN | 20 hr |
| Oct 27, 2:31 PM CDT | Wind Advisory | DVN | 26 hr |
| Nov 9, 10:26 AM CST | Special Weather Statement | DVN | 64 min |
| Nov 9, 11:16 AM CST | Special Weather Statement | DVN | 59 min |
| Nov 17, 7:47 PM CST | Winter Weather Advisory | DVN | 7 hr |
| Nov 23, 3:29 AM CST | Winter Storm Watch | DVN | 24 hr |
| Nov 24, 3:52 AM CST | Winter Storm Warning | DVN | 44 hr |
| Nov 25, 12:09 PM CST | Blizzard Warning | DVN | 18 hr |
| Nov 30, 3:37 AM CST | Dense Fog Advisory | DVN | 6 hr |
| Dec 1, 7:28 AM CST | Wind Advisory | DVN | 7 hr |
| Dec 1, 12:36 PM CST | Dense Fog Advisory | DVN | 20 hr |
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 | 11 |
| Tornado Warning | 1 |
| Severe Thunderstorm Watch | 4 |
| Tornado Watch | 3 |
| Mesoscale Discussion | 18 |
| Special Weather Statement | 41 |
| Flooding | |
| Flash Flood Watch | 6 |
| Flood Watch | 1 |
| Winter | |
| Blizzard Warning | 1 |
| Winter Storm Warning | 1 |
| Winter Storm Watch | 1 |
| Winter Weather Advisory | 14 |
| Heat | |
| Excessive Heat Warning | 1 |
| Heat Advisory | 6 |
| Cold | |
| Freeze Warning | 2 |
| Frost Advisory | 1 |
| Wind Chill Advisory | 3 |
| Wind and dust | |
| Wind Advisory | 3 |
| Fire | |
| Red Flag Warning | 1 |
| Fog and smoke | |
| Dense Fog Advisory | 5 |
The busiest days
Days with the most alerts issued, by UTC date.
Nearby
Alerts in force nowTornadoes on recordForecastThe radar archive20172019
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.