Alert archive / South Dakota / Stanley County

Weather alerts in Stanley County, South Dakota, 2009

129 weather alerts in 2009, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Stanley County and its neighbors

Each county as a circle sized by its count in 2009. Tap one for its archive.

Alerts
129
Warnings
35
Watches
30
Advisories
22
Busiest month
June37 alerts
Busiest day
June 16, 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.

2 of 4 tornado warnings covering Stanley County in 2009 had a tornado report inside them; 4 of 4 tornado reports fell inside a warning, on average 16 minutes after it went out.

Stanley County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings4250%4100%16 min
Severe thunderstorm warnings191047%1070%22 min
Flash flood warnings00

Each office's whole area, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Aberdeen, SD: tornado warnings24771%1080%19 min
NWS Aberdeen, SD: severe thunderstorm warnings1478641%17371%19 min
NWS Aberdeen, SD: flash flood warnings18856%2572%60 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.

IssuedProductOfficeLasted
Jan 9, 3:22 AM MSTWind AdvisoryABR11 hr
Jan 11, 1:54 PM MSTBlizzard WarningABR27 hr
Jan 11, 2:04 PM MSTWind AdvisoryABR9 hr
Jan 12, 4:34 AM MSTMesoscale DiscussionSPC4 hr
Jan 12, 9:56 AM MSTMesoscale DiscussionSPC6 hr
Jan 12, 11:08 AM MSTWind AdvisoryABR2 hr
Jan 13, 6:47 PM MSTWind Chill AdvisoryABR24 hr
Feb 1, 2:59 AM MSTWind AdvisoryABR7 hr
Feb 8, 10:02 AM MSTWinter Storm WatchABR27 hr
Feb 9, 6:00 PM MSTFlash Flood WatchABR12 hr
Feb 17, 3:33 AM MSTDense Fog AdvisoryABR5 hr
Feb 20, 1:32 AM MSTWind AdvisoryABR15 hr
Feb 24, 2:16 PM MSTWinter Storm WatchABR12 hr
Feb 25, 2:41 AM MSTWinter Storm WarningABR40 hr
Feb 25, 9:20 PM MSTMesoscale DiscussionSPC6 hr
Feb 27, 8:09 AM MSTWinter Weather AdvisoryABR9 hr
Feb 27, 10:25 AM MSTMesoscale DiscussionSPC4 hr
Feb 27, 11:00 AM MSTWinter Storm WarningABR8 hr
Mar 8, 10:42 AM MDTWinter Storm WatchABR28 hr
Mar 9, 2:23 PM MDTWinter Weather AdvisoryABR23 hr
Mar 10, 1:22 PM MDTWind Chill AdvisoryABR22 hr
Mar 22, 1:10 PM MDTBlizzard WarningABR55 hr
Mar 22, 1:10 PM MDTWinter Storm WatchABR14 hr
Mar 23, 11:16 AM MDTTornado WatchSPC4 hr
Mar 23, 5:56 PM MDTMesoscale DiscussionSPC3 hr
Mar 28, 3:37 AM MDTBlizzard WatchABR35 hr
Mar 29, 3:30 AM MDTBlizzard WarningABR65 hr
Mar 30, 2:20 PM MDTMesoscale DiscussionSPC6 hr
Apr 2, 2:23 PM MDTWinter Storm WatchABR13 hr
Apr 3, 3:37 AM MDTWinter Storm WarningABR41 hr
Apr 15, 10:27 AM MDTWind AdvisoryABR8 hr
May 12, 2:19 PM MDTMesoscale DiscussionSPC56 min
May 12, 3:00 PM MDTHigh Wind WatchABR11 hr
May 12, 6:08 PM MDTSevere Thunderstorm WatchSPC7 hr
May 13, 2:27 AM MDTHigh Wind WarningABR18 hr
May 13, 8:04 PM MDTWind AdvisoryABR2 hr
May 15, 2:23 PM MDTFreeze WarningABR17 hr
May 28, 4:18 PM MDTSevere Thunderstorm WarningABR27 min
May 29, 5:15 PM MDTMesoscale DiscussionSPC60 min
Jun 14, 4:09 PM MDTSevere Thunderstorm WatchSPC8 hr
Jun 14, 6:17 PM MDTMesoscale DiscussionSPC118 min
Jun 14, 9:18 PM MDTSpecial Weather StatementABR57 min
Jun 15, 3:08 PM MDTMesoscale DiscussionSPC67 min
Jun 15, 7:29 PM MDTSevere Thunderstorm WarningABR46 min
Jun 15, 8:17 PM MDTSevere Thunderstorm WarningABR43 min
Jun 15, 8:46 PM MDTTornado WarningABR29 min
Jun 15, 9:01 PM MDTSevere Thunderstorm WarningABR44 min
Jun 15, 9:15 PM MDTTornado WarningABR30 min
Jun 15, 9:26 PM MDTTornado WarningABR34 min
Jun 15, 9:46 PM MDTTornado WarningABR29 min
Jun 15, 10:15 PM MDTSpecial Weather StatementABR30 min
Jun 17, 4:02 PM MDTMesoscale DiscussionSPC88 min
Jun 17, 4:26 PM MDTMesoscale DiscussionSPC94 min
Jun 17, 5:35 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 17, 9:29 PM MDTSevere Thunderstorm WarningABR21 min
Jun 17, 11:01 PM MDTMesoscale DiscussionSPC89 min
Jun 18, 5:34 PM MDTSevere Thunderstorm WarningABR41 min
Jun 18, 5:49 PM MDTMesoscale DiscussionSPC86 min
Jun 21, 4:43 PM MDTMesoscale DiscussionSPC92 min
Jun 23, 3:43 AM MDTMesoscale DiscussionSPC92 min
Jun 24, 6:14 AM MDTMesoscale DiscussionSPC91 min
Jun 24, 12:46 PM MDTMesoscale DiscussionSPC119 min
Jun 24, 4:34 PM MDTMesoscale DiscussionSPC86 min
Jun 24, 5:16 PM MDTSevere Thunderstorm WatchSPC6 hr
Jun 24, 7:49 PM MDTMesoscale DiscussionSPC86 min
Jun 26, 2:31 AM MDTFlash Flood WatchABR21 hr
Jun 26, 1:53 PM MDTSevere Thunderstorm WatchSPC7 hr
Jun 26, 5:05 PM MDTMesoscale DiscussionSPC85 min
Jun 26, 5:24 PM MDTTornado WatchSPC4 hr
Jun 26, 5:45 PM MDTSevere Thunderstorm WarningABR60 min
Jun 26, 6:14 PM MDTSevere Thunderstorm WarningABR46 min
Jun 26, 6:59 PM MDTSevere Thunderstorm WarningABR46 min
Jun 26, 7:05 PM MDTSevere Thunderstorm WarningABR40 min
Jun 26, 7:55 PM MDTMesoscale DiscussionSPC95 min
Jun 29, 3:36 PM MDTMesoscale DiscussionSPC84 min
Jun 29, 6:51 PM MDTSevere Thunderstorm WarningABR54 min
Jul 8, 2:20 PM MDTTornado WatchSPC8 hr
Jul 8, 8:42 PM MDTMesoscale DiscussionSPC93 min
Jul 8, 8:58 PM MDTSevere Thunderstorm WatchSPC7 hr
Jul 8, 10:27 PM MDTMesoscale DiscussionSPC93 min
Jul 9, 2:07 AM MDTMesoscale DiscussionSPC83 min
Jul 13, 9:38 AM MDTMesoscale DiscussionSPC97 min
Jul 13, 9:57 AM MDTSevere Thunderstorm WatchSPC6 hr
Jul 13, 11:43 AM MDTMesoscale DiscussionSPC92 min
Jul 13, 12:05 PM MDTSevere Thunderstorm WarningABR55 min
Jul 13, 12:34 PM MDTTornado WatchSPC8 hr
Jul 13, 1:01 PM MDTSevere Thunderstorm WarningABR44 min
Jul 13, 7:47 PM MDTMesoscale DiscussionSPC58 min
Jul 13, 8:42 PM MDTTornado WatchSPC4 hr
Jul 13, 10:24 PM MDTMesoscale DiscussionSPC66 min
Jul 19, 6:28 PM MDTSevere Thunderstorm WatchSPC6 hr
Jul 19, 10:02 PM MDTMesoscale DiscussionSPC58 min
Jul 20, 2:01 PM MDTSevere Thunderstorm WarningABR28 min
Aug 3, 5:58 PM MDTMesoscale DiscussionSPC2 hr
Aug 3, 6:06 PM MDTSevere Thunderstorm WarningABR54 min
Aug 3, 6:35 PM MDTSevere Thunderstorm WarningABR40 min
Aug 6, 9:38 AM MDTMesoscale DiscussionSPC67 min
Aug 6, 2:53 PM MDTMesoscale DiscussionSPC97 min
Aug 7, 7:29 PM MDTMesoscale DiscussionSPC91 min
Aug 7, 7:57 PM MDTSevere Thunderstorm WatchSPC5 hr
Aug 7, 8:29 PM MDTSevere Thunderstorm WarningABR61 min
Aug 8, 9:52 AM MDTMesoscale DiscussionSPC23 min
Aug 14, 3:28 PM MDTSevere Thunderstorm WatchSPC6 hr
Aug 15, 5:52 PM MDTMesoscale DiscussionSPC53 min
Aug 15, 7:05 PM MDTSevere Thunderstorm WatchSPC5 hr
Aug 15, 8:19 PM MDTSevere Thunderstorm WarningABR41 min
Aug 18, 2:35 PM MDTMesoscale DiscussionSPC115 min
Aug 18, 4:58 PM MDTSevere Thunderstorm WarningABR47 min
Aug 18, 5:10 PM MDTSevere Thunderstorm WatchSPC5 hr
Sep 4, 2:45 AM MDTDense Fog AdvisoryABR6 hr
Sep 8, 1:32 PM MDTMesoscale DiscussionSPC88 min
Sep 26, 2:08 PM MDTWind AdvisoryABR28 hr
Sep 30, 10:07 AM MDTWind AdvisoryABR8 hr
Sep 30, 2:29 PM MDTWind AdvisoryABR48 hr
Oct 7, 1:23 PM MDTFreeze WatchABR13 hr
Oct 8, 2:37 AM MDTFreeze WarningABR30 hr
Oct 10, 1:51 PM MDTWinter Storm WatchABR24 hr
Oct 11, 1:35 AM MDTWinter Weather AdvisoryABR25 hr
Oct 27, 2:37 PM MDTWinter Storm WatchABR43 hr
Oct 28, 10:42 AM MDTWinter Storm WarningABR23 hr
Oct 29, 9:39 AM MDTWinter Weather AdvisoryABR4 hr
Dec 1, 2:46 AM MSTWind AdvisoryABR14 hr
Dec 8, 2:30 PM MSTWind Chill AdvisoryABR43 hr
Dec 13, 5:19 PM MSTWinter Weather AdvisoryABR8 hr
Dec 21, 1:16 PM MSTWinter Storm WatchABR14 hr
Dec 22, 2:58 AM MSTWinter Storm WarningABR55 hr
Dec 24, 9:45 AM MSTBlizzard WarningABR55 hr
Dec 25, 6:21 AM MSTMesoscale DiscussionSPC5 hr
Dec 26, 10:54 AM MSTWinter Weather AdvisoryABR12 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.