Alert archive / South Dakota / Fall River County
Weather alerts in Fall River County, South Dakota, 2009
96 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.
Fall River County and its neighbors
Each county as a circle sized by its count in 2009. Tap one for its archive.
- Alerts
- 96
- Warnings
- 33
- Watches
- 19
- Advisories
- 22
- Busiest month
- July24 alerts
- Busiest day
- June 14, 20098 alerts
Over time
By month
Warning verification
How often warnings here had a storm report inside them, and how much warning the reports had.
Fall River County, 2009
| Warnings | With a report | False alarm ratio | Reports | Inside a warning | Mean lead time | |
|---|---|---|---|---|---|---|
| Tornado warnings | 0 | 0 | ||||
| Severe thunderstorm warnings | 26 | 20 | 23% | 22 | 100% | 26 min |
| Flash flood warnings | 1 | 1 | 0% | 1 | 100% | 0 min |
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, Mountain Time. Each opens its own page with the text, the map, the radar and the sounding.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jan 24, 10:28 AM MST | Winter Weather Advisory | UNR | 53 hr |
| Jan 27, 4:08 PM MST | Winter Weather Advisory | UNR | 25 hr |
| Feb 12, 1:19 PM MST | Winter Weather Advisory | UNR | 25 hr |
| Mar 9, 3:23 AM MDT | Winter Weather Advisory | UNR | 33 hr |
| Mar 9, 8:49 PM MDT | Mesoscale Discussion | SPC | 4 hr |
| Mar 21, 3:03 AM MDT | Blizzard Watch | UNR | 24 hr |
| Mar 21, 5:23 PM MDT | Mesoscale Discussion | SPC | 97 min |
| Mar 22, 3:30 AM MDT | Blizzard Warning | UNR | 65 hr |
| Mar 29, 3:04 AM MDT | Winter Storm Warning | UNR | 51 hr |
| Mar 29, 3:15 PM MDT | Winter Weather Advisory | UNR | 5 hr |
| Apr 2, 4:06 AM MDT | Winter Storm Watch | UNR | 25 hr |
| Apr 3, 4:55 AM MDT | Winter Storm Warning | UNR | 41 hr |
| Apr 4, 4:57 AM MDT | Mesoscale Discussion | SPC | 4 hr |
| Apr 8, 2:36 PM MDT | Winter Weather Advisory | UNR | 25 hr |
| Apr 25, 3:47 AM MDT | Winter Weather Advisory | UNR | 35 hr |
| Apr 28, 3:41 AM MDT | Wind Advisory | UNR | 11 hr |
| May 12, 2:22 PM MDT | Wind Advisory | UNR | 29 hr |
| May 24, 5:53 PM MDT | Areal Flood Advisory | UNR | 5 hr |
| May 24, 6:31 PM MDT | Mesoscale Discussion | SPC | 119 min |
| May 31, 11:39 AM MDT | Severe Thunderstorm Warning | UNR | 44 min |
| May 31, 1:51 PM MDT | Severe Thunderstorm Warning | UNR | 39 min |
| Jun 13, 3:14 PM MDT | Severe Thunderstorm Warning | UNR | 61 min |
| Jun 13, 4:16 PM MDT | Severe Thunderstorm Warning | UNR | 16 min |
| Jun 13, 5:21 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 13, 7:58 PM MDT | Mesoscale Discussion | SPC | 62 min |
| Jun 13, 7:58 PM MDT | Severe Thunderstorm Warning | UNR | 92 min |
| Jun 13, 9:25 PM MDT | Severe Thunderstorm Warning | UNR | 30 min |
| Jun 13, 9:44 PM MDT | Flash Flood Warning | UNR | 6 hr |
| Jun 14, 3:53 AM MDT | Flood Watch | UNR | 19 hr |
| Jun 14, 2:22 PM MDT | Mesoscale Discussion | SPC | 83 min |
| Jun 14, 4:09 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Jun 14, 4:28 PM MDT | Severe Thunderstorm Warning | UNR | 62 min |
| Jun 23, 2:06 AM MDT | Severe Thunderstorm Warning | UNR | 69 min |
| Jun 25, 3:49 PM MDT | Mesoscale Discussion | SPC | 56 min |
| Jun 25, 3:50 PM MDT | Tornado Watch | SPC | 5 hr |
| Jun 25, 5:14 PM MDT | Severe Thunderstorm Warning | UNR | 61 min |
| Jun 25, 5:37 PM MDT | Severe Thunderstorm Warning | UNR | 30 min |
| Jun 25, 6:33 PM MDT | Mesoscale Discussion | SPC | 57 min |
| Jun 26, 3:04 AM MDT | Flash Flood Watch | UNR | 18 hr |
| Jun 26, 1:53 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 29, 3:36 PM MDT | Mesoscale Discussion | SPC | 84 min |
| Jun 30, 2:52 PM MDT | Mesoscale Discussion | SPC | 83 min |
| Jun 30, 3:19 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jun 30, 5:22 PM MDT | Areal Flood Advisory | UNR | 2 hr |
| Jun 30, 6:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jul 1, 12:33 PM MDT | Mesoscale Discussion | SPC | 117 min |
| Jul 1, 4:29 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Jul 1, 5:24 PM MDT | Severe Thunderstorm Warning | UNR | 70 min |
| Jul 2, 11:41 AM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Jul 2, 2:17 PM MDT | Mesoscale Discussion | SPC | 88 min |
| Jul 2, 6:29 PM MDT | Mesoscale Discussion | SPC | 61 min |
| Jul 2, 6:54 PM MDT | Severe Thunderstorm Warning | UNR | 66 min |
| Jul 2, 9:42 PM MDT | Areal Flood Warning | UNR | 12 hr |
| Jul 3, 9:34 PM MDT | Areal Flood Advisory | UNR | 48 hr |
| Jul 7, 9:29 PM MDT | Areal Flood Advisory | UNR | 13 hr |
| Jul 8, 5:07 PM MDT | Severe Thunderstorm Warning | UNR | 53 min |
| Jul 9, 8:59 PM MDT | Mesoscale Discussion | SPC | 91 min |
| Jul 9, 10:08 PM MDT | Severe Thunderstorm Warning | UNR | 67 min |
| Jul 9, 11:06 PM MDT | Severe Thunderstorm Warning | UNR | 54 min |
| Jul 9, 11:50 PM MDT | Severe Thunderstorm Warning | UNR | 55 min |
| Jul 11, 4:53 AM MDT | Severe Thunderstorm Warning | UNR | 39 min |
| Jul 13, 12:34 PM MDT | Tornado Watch | SPC | 8 hr |
| Jul 13, 6:22 PM MDT | Severe Thunderstorm Warning | UNR | 53 min |
| Jul 13, 7:03 PM MDT | Severe Thunderstorm Warning | UNR | 57 min |
| Jul 13, 7:43 PM MDT | Severe Thunderstorm Warning | UNR | 62 min |
| Jul 19, 2:22 PM MDT | Mesoscale Discussion | SPC | 113 min |
| Jul 20, 3:10 PM MDT | Areal Flood Advisory | UNR | 3 hr |
| Jul 20, 5:01 PM MDT | Mesoscale Discussion | SPC | 89 min |
| Aug 3, 6:46 PM MDT | Mesoscale Discussion | SPC | 119 min |
| Aug 3, 6:53 PM MDT | Severe Thunderstorm Warning | UNR | 67 min |
| Aug 3, 7:59 PM MDT | Severe Thunderstorm Warning | UNR | 61 min |
| Aug 4, 3:37 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
| Aug 4, 5:19 PM MDT | Mesoscale Discussion | SPC | 56 min |
| Aug 4, 6:40 PM MDT | Mesoscale Discussion | SPC | 65 min |
| Aug 4, 6:58 PM MDT | Severe Thunderstorm Warning | UNR | 77 min |
| Aug 4, 7:54 PM MDT | Severe Thunderstorm Warning | UNR | 81 min |
| Aug 4, 8:37 PM MDT | Severe Thunderstorm Warning | UNR | 41 min |
| Aug 6, 11:00 AM MDT | Flash Flood Watch | UNR | 9 hr |
| Aug 6, 4:07 PM MDT | Tornado Watch | SPC | 4 hr |
| Aug 7, 4:56 PM MDT | Severe Thunderstorm Watch | SPC | 6 hr |
| Aug 8, 2:18 AM MDT | Mesoscale Discussion | SPC | 117 min |
| Aug 15, 2:08 PM MDT | Severe Thunderstorm Watch | SPC | 8 hr |
| Aug 15, 4:31 PM MDT | Severe Thunderstorm Warning | UNR | 59 min |
| Sep 27, 2:34 PM MDT | Frost Advisory | UNR | 17 hr |
| Sep 30, 3:00 PM MDT | Wind Advisory | UNR | 48 hr |
| Oct 2, 3:46 AM MDT | Freeze Warning | UNR | 29 hr |
| Oct 7, 3:37 AM MDT | Winter Weather Advisory | UNR | 24 hr |
| Oct 10, 2:23 PM MDT | Winter Storm Watch | UNR | 13 hr |
| Oct 11, 3:35 AM MDT | Winter Weather Advisory | UNR | 24 hr |
| Oct 27, 3:16 PM MDT | Winter Storm Watch | UNR | 13 hr |
| Oct 28, 4:32 AM MDT | Winter Storm Warning | UNR | 46 hr |
| Oct 28, 4:32 AM MDT | Winter Weather Advisory | UNR | 46 hr |
| Dec 8, 2:33 PM MST | Wind Chill Advisory | UNR | 21 hr |
| Dec 9, 2:55 PM MST | Wind Chill Advisory | UNR | 13 hr |
| Dec 21, 1:28 PM MST | Winter Storm Watch | UNR | 39 hr |
| Dec 22, 12:36 PM MST | Winter Weather Advisory | UNR | 4 days |
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.