Alert archive / South Dakota / Todd County
Weather alerts in Todd County, South Dakota, 2009
140 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Todd County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 140
- Warnings
- 42
- Watches
- 30
- Advisories
- 26
- Busiest month
- June28 alerts
- Busiest day
- July 9, 200910 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
2 of 8 tornado warnings covering Todd County in 2009 had a tornado report inside them; 3 of 4 tornado reports fell inside a warning, on average 22 minutes after it went out.
Todd County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 8 | 2 | 75% | 4 | 75% | 22 min |
| Severe thunderstorm warnings | 23 | 12 | 48% | 23 | 39% | 34 min |
| Flash flood warnings | 0 | 0 |
Each office's whole area, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| NWS Rapid City, SD: tornado warnings | 27 | 6 | 78% | 10 | 90% | 19 min |
| NWS Rapid City, SD: severe thunderstorm warnings | 262 | 172 | 34% | 345 | 79% | 27 min |
| NWS Rapid City, SD: flash flood warnings | 10 | 4 | 60% | 4 | 75% | 59 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 8, 3:25 PM CST | Wind Advisory | UNR | 26 hr |
| Jan 11, 5:23 AM CST | High Wind Warning | UNR | 32 hr |
| Jan 11, 3:23 PM CST | Wind Advisory | UNR | 12 hr |
| Jan 12, 10:56 AM CST | Mesoscale Discussion | SPC | 6 hr |
| Jan 12, 1:16 PM CST | Wind Advisory | UNR | 2 hr |
| Jan 13, 9:08 PM CST | Wind Chill Advisory | UNR | 16 hr |
| Jan 18, 4:34 AM CST | Wind Advisory | UNR | 13 hr |
| Jan 19, 4:35 AM CST | Wind Advisory | UNR | 11 hr |
| Jan 24, 11:28 AM CST | Winter Weather Advisory | UNR | 53 hr |
| Jan 27, 2:39 PM CST | Wind Advisory | UNR | 28 hr |
| Jan 27, 5:08 PM CST | Winter Weather Advisory | UNR | 25 hr |
| Feb 26, 2:07 PM CST | Winter Weather Advisory | UNR | 26 hr |
| Feb 27, 11:25 AM CST | Mesoscale Discussion | SPC | 4 hr |
| Feb 27, 12:04 PM CST | Winter Storm Warning | UNR | 6 hr |
| Mar 9, 4:23 AM CDT | Winter Weather Advisory | UNR | 33 hr |
| Mar 10, 3:07 PM CDT | Wind Chill Advisory | UNR | 20 hr |
| Mar 22, 4:30 AM CDT | Blizzard Warning | UNR | 65 hr |
| Mar 22, 3:27 PM CDT | Winter Storm Watch | UNR | 13 hr |
| Mar 23, 12:16 PM CDT | Tornado Watch | SPC | 4 hr |
| Mar 23, 3:48 PM CDT | Tornado Warning | UNR | 42 min |
| Mar 23, 3:50 PM CDT | Tornado Watch | SPC | 6 hr |
| Mar 29, 4:04 AM CDT | Blizzard Warning | UNR | 57 hr |
| Mar 29, 4:04 AM CDT | Winter Storm Watch | UNR | 12 hr |
| Mar 29, 4:04 AM CDT | Winter Storm Warning | UNR | 51 hr |
| Mar 30, 3:20 PM CDT | Mesoscale Discussion | SPC | 6 hr |
| Mar 30, 7:59 PM CDT | Mesoscale Discussion | SPC | 4 hr |
| Apr 2, 5:06 AM CDT | Winter Storm Watch | UNR | 25 hr |
| Apr 3, 5:55 AM CDT | Blizzard Warning | UNR | 46 hr |
| Apr 4, 5:57 AM CDT | Mesoscale Discussion | SPC | 4 hr |
| Apr 9, 4:07 PM CDT | Flood Watch | UNR | 72 hr |
| Apr 15, 12:57 PM CDT | Wind Advisory | UNR | 6 hr |
| May 12, 3:22 PM CDT | Wind Advisory | UNR | 29 hr |
| May 12, 6:51 PM CDT | Severe Thunderstorm Warning | UNR | 38 min |
| May 12, 6:57 PM CDT | Severe Thunderstorm Warning | UNR | 63 min |
| May 12, 7:08 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| May 12, 7:33 PM CDT | Severe Thunderstorm Warning | UNR | 39 min |
| May 19, 2:53 PM CDT | Wind Advisory | UNR | 5 hr |
| May 20, 3:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| May 29, 6:15 PM CDT | Mesoscale Discussion | SPC | 60 min |
| Jun 13, 5:26 PM CDT | Mesoscale Discussion | SPC | 64 min |
| Jun 13, 6:21 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 13, 8:58 PM CDT | Mesoscale Discussion | SPC | 62 min |
| Jun 14, 5:09 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 14, 7:17 PM CDT | Mesoscale Discussion | SPC | 118 min |
| Jun 15, 4:08 PM CDT | Mesoscale Discussion | SPC | 67 min |
| Jun 15, 8:04 PM CDT | Severe Thunderstorm Warning | UNR | 24 min |
| Jun 15, 8:49 PM CDT | Severe Thunderstorm Warning | UNR | 56 min |
| Jun 17, 3:38 PM CDT | Severe Thunderstorm Warning | UNR | 42 min |
| Jun 17, 4:47 PM CDT | Severe Thunderstorm Warning | UNR | 38 min |
| Jun 17, 5:02 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Jun 17, 5:26 PM CDT | Mesoscale Discussion | SPC | 94 min |
| Jun 17, 6:35 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 18, 12:01 AM CDT | Mesoscale Discussion | SPC | 89 min |
| Jun 18, 6:52 PM CDT | Mesoscale Discussion | SPC | 113 min |
| Jun 23, 1:07 AM CDT | Mesoscale Discussion | SPC | 53 min |
| Jun 23, 1:38 AM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Jun 23, 3:17 AM CDT | Mesoscale Discussion | SPC | 88 min |
| Jun 23, 4:43 AM CDT | Mesoscale Discussion | SPC | 92 min |
| Jun 24, 8:39 PM CDT | Tornado Warning | UNR | 66 min |
| Jun 26, 4:04 AM CDT | Flash Flood Watch | UNR | 18 hr |
| Jun 26, 6:05 PM CDT | Mesoscale Discussion | SPC | 85 min |
| Jun 26, 6:24 PM CDT | Tornado Watch | SPC | 4 hr |
| Jun 26, 6:55 PM CDT | Severe Thunderstorm Warning | UNR | 65 min |
| Jun 26, 7:32 PM CDT | Severe Thunderstorm Warning | UNR | 73 min |
| Jun 26, 8:31 PM CDT | Severe Thunderstorm Warning | UNR | 74 min |
| Jun 26, 8:55 PM CDT | Mesoscale Discussion | SPC | 95 min |
| Jun 29, 4:36 PM CDT | Mesoscale Discussion | SPC | 84 min |
| Jul 1, 1:33 PM CDT | Mesoscale Discussion | SPC | 117 min |
| Jul 7, 11:05 PM CDT | Mesoscale Discussion | SPC | 55 min |
| Jul 8, 3:20 PM CDT | Tornado Watch | SPC | 8 hr |
| Jul 8, 9:36 PM CDT | Tornado Warning | UNR | 39 min |
| Jul 8, 9:42 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Jul 8, 9:58 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 8, 10:06 PM CDT | Severe Thunderstorm Warning | UNR | 54 min |
| Jul 8, 10:50 PM CDT | Tornado Warning | UNR | 40 min |
| Jul 8, 11:02 PM CDT | Severe Thunderstorm Warning | UNR | 88 min |
| Jul 8, 11:23 PM CDT | Tornado Warning | UNR | 52 min |
| Jul 8, 11:27 PM CDT | Mesoscale Discussion | SPC | 93 min |
| Jul 9, 12:12 AM CDT | Tornado Warning | UNR | 63 min |
| Jul 9, 3:07 AM CDT | Mesoscale Discussion | SPC | 83 min |
| Jul 11, 7:14 AM CDT | Mesoscale Discussion | SPC | 61 min |
| Jul 11, 9:10 AM CDT | Severe Thunderstorm Warning | UNR | 45 min |
| Jul 13, 1:34 PM CDT | Tornado Watch | SPC | 8 hr |
| Jul 13, 6:13 PM CDT | Tornado Warning | UNR | 47 min |
| Jul 13, 6:56 PM CDT | Areal Flood Advisory | UNR | 6 hr |
| Jul 13, 6:57 PM CDT | Tornado Warning | UNR | 63 min |
| Jul 13, 8:47 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Jul 13, 9:42 PM CDT | Tornado Watch | SPC | 4 hr |
| Jul 13, 10:04 PM CDT | Severe Thunderstorm Warning | UNR | 56 min |
| Jul 13, 10:15 PM CDT | Areal Flood Advisory | UNR | 9 hr |
| Jul 20, 12:54 AM CDT | Severe Thunderstorm Warning | UNR | 66 min |
| Jul 31, 1:35 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Aug 3, 6:58 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Aug 4, 10:01 PM CDT | Severe Thunderstorm Warning | UNR | 74 min |
| Aug 4, 10:30 PM CDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 4, 11:37 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Aug 6, 5:07 PM CDT | Tornado Watch | SPC | 4 hr |
| Aug 6, 9:15 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 7, 8:57 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 7, 11:22 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Aug 8, 2:38 AM CDT | Severe Thunderstorm Warning | UNR | 67 min |
| Aug 8, 10:52 AM CDT | Mesoscale Discussion | SPC | 23 min |
| Aug 8, 11:15 AM CDT | Severe Thunderstorm Watch | SPC | 4 hr |
| Aug 12, 2:22 PM CDT | Mesoscale Discussion | SPC | 83 min |
| Aug 13, 9:07 PM CDT | Severe Thunderstorm Warning | UNR | 68 min |
| Aug 14, 2:32 PM CDT | Mesoscale Discussion | SPC | 58 min |
| Aug 14, 4:28 PM CDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 14, 7:45 PM CDT | Mesoscale Discussion | SPC | 60 min |
| Aug 15, 3:08 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 15, 6:52 PM CDT | Mesoscale Discussion | SPC | 53 min |
| Aug 15, 6:54 PM CDT | Severe Thunderstorm Warning | UNR | 66 min |
| Aug 18, 3:35 PM CDT | Mesoscale Discussion | SPC | 115 min |
| Aug 18, 6:10 PM CDT | Severe Thunderstorm Watch | SPC | 5 hr |
| Aug 18, 6:21 PM CDT | Severe Thunderstorm Warning | UNR | 54 min |
| Sep 8, 2:32 PM CDT | Mesoscale Discussion | SPC | 88 min |
| Sep 8, 2:53 PM CDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Sep 8, 3:13 PM CDT | Severe Thunderstorm Warning | UNR | 62 min |
| Sep 8, 3:50 PM CDT | Severe Thunderstorm Warning | UNR | 70 min |
| Sep 8, 3:59 PM CDT | Severe Thunderstorm Warning | UNR | 76 min |
| Sep 8, 7:10 PM CDT | Mesoscale Discussion | SPC | 2 hr |
| Sep 26, 3:39 AM CDT | Wind Advisory | UNR | 39 hr |
| Sep 29, 4:29 AM CDT | High Wind Watch | UNR | 36 hr |
| Sep 30, 4:00 PM CDT | Wind Advisory | UNR | 48 hr |
| Sep 30, 6:01 PM CDT | Mesoscale Discussion | SPC | 89 min |
| Oct 2, 4:46 AM CDT | Freeze Warning | UNR | 29 hr |
| Oct 2, 6:54 AM CDT | High Wind Warning | UNR | 9 hr |
| Oct 10, 3:23 PM CDT | Winter Storm Watch | UNR | 13 hr |
| Oct 11, 4:35 AM CDT | Winter Weather Advisory | UNR | 24 hr |
| Oct 27, 4:16 PM CDT | Winter Storm Watch | UNR | 13 hr |
| Oct 28, 5:32 AM CDT | Winter Storm Warning | UNR | 46 hr |
| Nov 30, 2:08 PM CST | Wind Advisory | UNR | 28 hr |
| Dec 7, 4:23 PM CST | Winter Weather Advisory | UNR | 36 hr |
| Dec 8, 3:33 PM CST | Wind Chill Advisory | UNR | 21 hr |
| Dec 9, 3:55 PM CST | Wind Chill Advisory | UNR | 13 hr |
| Dec 21, 2:28 PM CST | Winter Storm Watch | UNR | 39 hr |
| Dec 21, 9:45 PM CST | Dense Fog Advisory | UNR | 10 hr |
| Dec 22, 5:23 AM CST | Winter Storm Warning | UNR | 5 days |
| Dec 24, 3:33 PM CST | Blizzard Warning | UNR | 56 hr |
| Dec 25, 7:21 AM CST | Mesoscale Discussion | SPC | 5 hr |
| Dec 26, 11:25 PM CST | Winter Weather Advisory | UNR | 4 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 | 23 |
| Tornado Warning | 8 |
| Severe Thunderstorm Watch | 14 |
| Tornado Watch | 7 |
| Mesoscale Discussion | 42 |
| Flooding | |
| Flash Flood Watch | 1 |
| Flood Watch | 1 |
| Areal Flood Advisory | 2 |
| Winter | |
| Blizzard Warning | 4 |
| Winter Storm Warning | 4 |
| Winter Storm Watch | 6 |
| Winter Weather Advisory | 7 |
| Cold | |
| Freeze Warning | 1 |
| Wind Chill Advisory | 4 |
| Wind and dust | |
| High Wind Warning | 2 |
| High Wind Watch | 1 |
| Wind Advisory | 12 |
| Fog and smoke | |
| Dense Fog Advisory | 1 |
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.