Alert archive / South Dakota / Marshall County

Weather alerts in Marshall County, South Dakota, 2009

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

Marshall County and its neighbors

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

Alerts
95
Warnings
20
Watches
19
Advisories
29
Busiest month
January17 alerts
Busiest day
April 30, 20095 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

Marshall County, 2009

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings770%1100%29 min
Flash flood warnings110%0

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, Central Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 2, 3:33 PM CSTWinter Weather AdvisoryABR30 hr
Jan 3, 2:57 PM CSTWind Chill AdvisoryABR20 hr
Jan 8, 4:58 AM CSTWinter Weather AdvisoryABR34 hr
Jan 11, 3:58 AM CSTBlizzard WatchABR11 hr
Jan 11, 2:54 PM CSTBlizzard WarningABR27 hr
Jan 12, 5:34 AM CSTMesoscale DiscussionSPC4 hr
Jan 12, 10:56 AM CSTMesoscale DiscussionSPC6 hr
Jan 12, 7:12 PM CSTWind Chill AdvisoryABR5 hr
Jan 13, 4:16 AM CSTWinter Weather AdvisoryABR16 hr
Jan 13, 11:50 AM CSTMesoscale DiscussionSPC6 hr
Jan 13, 7:47 PM CSTWind Chill AdvisoryABR24 hr
Jan 14, 5:30 AM CSTWind Chill WarningABR9 hr
Jan 14, 2:22 PM CSTWind Chill WarningABR6 hr
Jan 14, 8:14 PM CSTWind Chill WarningABR8 hr
Jan 15, 3:48 AM CSTWind Chill WarningABR6 hr
Jan 23, 3:49 AM CSTWind Chill AdvisoryABR32 hr
Jan 31, 2:08 PM CSTWind AdvisoryABR5 hr
Feb 2, 11:51 AM CSTWind Chill AdvisoryABR15 hr
Feb 8, 11:02 AM CSTWinter Storm WatchABR27 hr
Feb 10, 4:09 AM CSTDense Fog AdvisoryABR3 hr
Feb 17, 4:33 AM CSTDense Fog AdvisoryABR5 hr
Feb 20, 2:54 AM CSTWinter Weather AdvisoryABR18 hr
Feb 24, 3:16 PM CSTWinter Storm WatchABR12 hr
Feb 25, 3:41 AM CSTWinter Storm WarningABR40 hr
Feb 25, 10:20 PM CSTMesoscale DiscussionSPC6 hr
Feb 26, 6:33 AM CSTMesoscale DiscussionSPC5 hr
Feb 26, 3:13 PM CSTWind Chill AdvisoryABR21 hr
Mar 8, 11:42 AM CDTWinter Storm WatchABR28 hr
Mar 9, 3:41 AM CDTBlizzard WatchABR12 hr
Mar 9, 3:23 PM CDTBlizzard WarningABR32 hr
Mar 10, 2:22 PM CDTWind Chill AdvisoryABR22 hr
Mar 21, 4:22 AM CDTDense Fog AdvisoryABR5 hr
Mar 22, 4:19 AM CDTFlood WatchABR27 hr
Mar 22, 4:24 AM CDTWind AdvisoryABR11 hr
Mar 28, 4:37 AM CDTBlizzard WatchABR35 hr
Mar 29, 4:30 AM CDTBlizzard WarningABR65 hr
Mar 30, 3:20 PM CDTMesoscale DiscussionSPC6 hr
Mar 30, 7:59 PM CDTMesoscale DiscussionSPC4 hr
Mar 31, 1:22 AM CDTMesoscale DiscussionSPC4 hr
Mar 31, 7:02 AM CDTMesoscale DiscussionSPC4 hr
Apr 29, 8:17 PM CDTSpecial Weather StatementABR3 hr
Apr 29, 8:52 PM CDTSpecial Weather StatementABR38 min
Apr 29, 9:08 PM CDTSevere Thunderstorm WarningABR37 min
Apr 29, 9:36 PM CDTSevere Thunderstorm WarningABR39 min
Apr 29, 10:06 PM CDTSevere Thunderstorm WarningABR54 min
May 12, 4:13 AM CDTWind AdvisoryABR12 hr
May 12, 4:00 PM CDTWind AdvisoryABR29 hr
May 12, 8:42 PM CDTMesoscale DiscussionSPC93 min
May 13, 9:04 PM CDTWind AdvisoryABR2 hr
May 15, 3:23 PM CDTFreeze WarningABR17 hr
Jun 16, 1:13 PM CDTAreal Flood AdvisoryABR3 hr
Jun 16, 2:05 PM CDTTornado WatchSPC6 hr
Jun 18, 12:52 PM CDTMesoscale DiscussionSPC83 min
Jun 18, 1:50 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 24, 7:41 PM CDTSevere Thunderstorm WarningABR49 min
Jun 24, 8:14 PM CDTSevere Thunderstorm WarningABR49 min
Jun 26, 3:31 AM CDTFlash Flood WatchABR21 hr
Jun 26, 6:24 PM CDTTornado WatchSPC4 hr
Jun 27, 12:37 PM CDTMesoscale DiscussionSPC53 min
Jun 27, 1:39 PM CDTSevere Thunderstorm WatchSPC7 hr
Jun 27, 3:16 PM CDTMesoscale DiscussionSPC59 min
Jun 27, 5:02 PM CDTMesoscale DiscussionSPC58 min
Jun 27, 7:16 PM CDTMesoscale DiscussionSPC59 min
Jul 6, 2:58 PM CDTMesoscale DiscussionSPC32 min
Jul 7, 10:14 AM CDTMesoscale DiscussionSPC91 min
Jul 8, 9:58 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 8, 11:27 PM CDTMesoscale DiscussionSPC93 min
Jul 9, 3:07 AM CDTMesoscale DiscussionSPC83 min
Jul 14, 1:17 AM CDTFlash Flood WarningABR3 hr
Jul 20, 1:07 PM CDTMesoscale DiscussionSPC83 min
Jul 31, 4:33 PM CDTSevere Thunderstorm WarningABR42 min
Aug 2, 2:35 PM CDTMesoscale DiscussionSPC115 min
Aug 3, 7:46 PM CDTSevere Thunderstorm WarningABR34 min
Aug 8, 11:15 AM CDTSevere Thunderstorm WatchSPC4 hr
Aug 8, 2:17 PM CDTMesoscale DiscussionSPC58 min
Aug 14, 3:42 PM CDTMesoscale DiscussionSPC93 min
Aug 14, 5:40 PM CDTSevere Thunderstorm WatchSPC5 hr
Aug 14, 8:37 PM CDTMesoscale DiscussionSPC53 min
Sep 4, 3:45 AM CDTDense Fog AdvisoryABR6 hr
Sep 8, 2:53 PM CDTSevere Thunderstorm WatchSPC8 hr
Sep 8, 7:10 PM CDTMesoscale DiscussionSPC2 hr
Sep 10, 10:22 AM CDTFlood WatchABR19 hr
Sep 26, 3:08 PM CDTWind AdvisoryABR28 hr
Sep 28, 3:49 AM CDTFrost AdvisoryABR29 hr
Sep 30, 11:07 AM CDTWind AdvisoryABR8 hr
Oct 7, 2:23 PM CDTFreeze WatchABR13 hr
Oct 8, 3:37 AM CDTFreeze WarningABR30 hr
Dec 1, 3:46 AM CSTWind AdvisoryABR14 hr
Dec 8, 3:30 PM CSTWind Chill AdvisoryABR43 hr
Dec 13, 4:02 AM CSTWind Chill AdvisoryABR8 hr
Dec 14, 3:52 PM CSTWind Chill AdvisoryABR19 hr
Dec 21, 2:16 PM CSTWinter Storm WatchABR14 hr
Dec 22, 3:58 AM CSTWinter Storm WarningABR55 hr
Dec 24, 10:45 AM CSTBlizzard WarningABR55 hr
Dec 26, 11:54 AM CSTWinter 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.