Alert archive / Michigan / Ottawa County

Weather alerts in Ottawa County, Michigan, 2020

135 weather alerts in 2020, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Ottawa County and its neighbors

Each county as a circle sized by its count in 2020. Tap one for its archive.

Alerts
135
Warnings
24
Watches
17
Advisories
42
Busiest month
June20 alerts
Busiest day
June 10, 20205 alerts

Over time

By month

Warning verification

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

Ottawa County, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings9544%1191%41 min
Flash flood warnings00

Each office's whole area, 2020

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Grand Rapids, MI: severe thunderstorm warnings874944%19875%30 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, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 3, 2:58 PM ESTLakeshore Flood AdvisoryGRR70 hr
Jan 6, 3:34 PM ESTLakeshore Flood AdvisoryGRR43 hr
Jan 9, 10:15 AM ESTWinter Storm WatchGRR18 hr
Jan 10, 3:47 AM ESTWinter Storm WarningGRR47 hr
Jan 11, 5:43 AM ESTAreal Flood AdvisoryGRR22 hr
Jan 11, 12:06 PM ESTRiver Flood WarningGRR10 days
Jan 12, 9:54 PM ESTWinter Weather AdvisoryGRR11 hr
Jan 15, 11:14 AM ESTLakeshore Flood AdvisoryGRR29 hr
Jan 16, 3:46 PM ESTWinter Weather AdvisoryGRR72 hr
Jan 16, 4:05 PM ESTLakeshore Flood WatchGRR5 hr
Jan 16, 9:15 PM ESTLakeshore Flood WarningGRR68 hr
Jan 21, 12:19 PM ESTLakeshore Flood AdvisoryGRR28 hr
Feb 8, 2:29 PM ESTWinter Weather AdvisoryGRR33 hr
Feb 9, 4:34 PM ESTMesoscale DiscussionSPC3 hr
Feb 11, 3:47 PM ESTWinter Weather AdvisoryGRR66 hr
Feb 14, 9:56 AM ESTLakeshore Flood AdvisoryGRR31 hr
Feb 17, 3:35 AM ESTWinter Weather AdvisoryGRR30 hr
Feb 21, 4:08 AM ESTLakeshore Flood AdvisoryGRR21 hr
Feb 24, 2:18 PM ESTWinter Storm WatchGRR25 hr
Mar 19, 3:48 AM EDTLakeshore Flood AdvisoryGRR40 hr
Mar 28, 2:40 PM EDTWind AdvisoryGRR29 hr
Mar 28, 3:38 PM EDTLakeshore Flood AdvisoryGRR31 hr
Apr 7, 4:06 PM EDTMesoscale DiscussionSPC114 min
Apr 7, 4:55 PM EDTSevere Thunderstorm WatchSPC5 hr
Apr 7, 6:59 PM EDTMesoscale DiscussionSPC91 min
Apr 7, 7:17 PM EDTSevere Thunderstorm WarningGRR88 min
Apr 8, 3:54 PM EDTLakeshore Flood AdvisoryGRR40 hr
Apr 11, 3:29 PM EDTHigh Wind WatchGRR21 hr
Apr 11, 3:29 PM EDTLakeshore Flood WatchGRR12 hr
Apr 12, 3:37 AM EDTLakeshore Flood WarningGRR41 hr
Apr 12, 12:42 PM EDTWind AdvisoryGRR31 hr
Apr 15, 3:19 PM EDTFreeze WarningGRR17 hr
Apr 20, 11:27 PM EDTSpecial Weather StatementGRR63 min
Apr 21, 3:13 PM EDTFreeze WarningGRR17 hr
Apr 28, 3:33 AM EDTDense Fog AdvisoryGRR6 hr
Apr 28, 3:31 PM EDTLakeshore Flood AdvisoryGRR52 hr
Apr 29, 3:11 PM EDTAreal Flood AdvisoryGRR24 hr
May 7, 3:33 AM EDTFreeze WatchGRR12 hr
May 7, 3:17 PM EDTFreeze WarningGRR42 hr
May 9, 2:46 PM EDTLakeshore Flood AdvisoryGRR37 hr
May 11, 3:36 AM EDTFreeze WarningGRR29 hr
May 12, 2:48 PM EDTFreeze WarningGRR18 hr
May 15, 5:47 AM EDTAreal Flood AdvisoryGRR5 hr
May 16, 11:56 AM EDTFlood WatchGRR21 hr
May 16, 3:30 PM EDTLakeshore Flood WarningGRR57 hr
May 17, 8:26 AM EDTFlood WatchGRR18 hr
May 17, 12:26 PM EDTRiver Flood WarningGRR14 days
May 17, 3:38 PM EDTAreal Flood WarningGRR30 hr
May 19, 6:07 AM EDTLakeshore Flood AdvisoryGRR40 hr
May 26, 6:39 PM EDTAreal Flood AdvisoryGRR3 hr
May 27, 3:10 PM EDTSpecial Weather StatementGRR4 hr
Jun 1, 3:57 AM EDTBeach Hazards StatementGRR34 hr
Jun 2, 10:28 PM EDTMesoscale DiscussionSPC2 hr
Jun 2, 10:50 PM EDTSevere Thunderstorm WatchSPC3 hr
Jun 3, 12:12 AM EDTSpecial Weather StatementGRR93 min
Jun 6, 3:45 AM EDTBeach Hazards StatementGRR17 hr
Jun 9, 3:42 AM EDTWind AdvisoryGRR28 hr
Jun 9, 3:32 PM EDTBeach Hazards StatementGRR54 hr
Jun 9, 5:16 PM EDTSpecial Weather StatementGRR3 hr
Jun 9, 7:11 PM EDTSevere Thunderstorm WarningGRR49 min
Jun 10, 12:17 AM EDTSevere Thunderstorm WarningGRR21 min
Jun 10, 9:33 AM EDTSpecial Weather StatementGRR72 min
Jun 10, 9:44 AM EDTMesoscale DiscussionSPC91 min
Jun 10, 10:59 AM EDTSevere Thunderstorm WatchSPC6 hr
Jun 10, 11:12 AM EDTSevere Thunderstorm WarningGRR71 min
Jun 11, 6:39 PM EDTSpecial Weather StatementGRR51 min
Jun 22, 6:01 AM EDTBeach Hazards StatementGRR38 hr
Jun 26, 6:09 PM EDTSpecial Weather StatementGRR111 min
Jun 26, 7:11 PM EDTAreal Flood AdvisoryGRR9 hr
Jun 26, 7:39 PM EDTMesoscale DiscussionSPC66 min
Jun 26, 7:57 PM EDTSevere Thunderstorm WatchSPC7 hr
Jul 9, 1:16 PM EDTSpecial Weather StatementGRR4 hr
Jul 9, 10:03 PM EDTBeach Hazards StatementGRR25 hr
Jul 11, 3:51 PM EDTBeach Hazards StatementGRR30 hr
Jul 12, 9:32 PM EDTBeach Hazards StatementGRR5 hr
Jul 17, 3:43 PM EDTBeach Hazards StatementGRR56 hr
Jul 18, 4:19 AM EDTHeat AdvisoryGRR17 hr
Jul 18, 2:10 PM EDTSpecial Weather StatementGRR110 min
Jul 26, 10:45 AM EDTBeach Hazards StatementGRR11 hr
Jul 26, 6:33 PM EDTMesoscale DiscussionSPC87 min
Jul 28, 8:37 PM EDTSevere Thunderstorm WarningGRR29 min
Jul 28, 9:46 PM EDTSevere Thunderstorm WarningGRR41 min
Jul 29, 9:23 PM EDTBeach Hazards StatementGRR29 hr
Aug 2, 10:10 AM EDTBeach Hazards StatementGRR59 hr
Aug 10, 4:26 PM EDTSevere Thunderstorm WatchSPC5 hr
Aug 10, 4:36 PM EDTMesoscale DiscussionSPC84 min
Aug 10, 5:49 PM EDTSevere Thunderstorm WarningGRR86 min
Aug 10, 6:17 PM EDTMesoscale DiscussionSPC118 min
Aug 17, 3:00 PM EDTBeach Hazards StatementGRR35 hr
Aug 25, 11:07 AM EDTMesoscale DiscussionSPC113 min
Aug 26, 3:20 AM EDTBeach Hazards StatementGRR34 hr
Aug 27, 5:49 PM EDTSpecial Weather StatementGRR56 min
Aug 28, 3:45 AM EDTBeach Hazards StatementGRR52 hr
Aug 28, 1:50 PM EDTMesoscale DiscussionSPC85 min
Aug 28, 8:49 PM EDTSevere Thunderstorm WarningGRR56 min
Aug 28, 9:15 PM EDTMesoscale DiscussionSPC3 hr
Sep 2, 6:38 AM EDTBeach Hazards StatementGRR63 hr
Sep 3, 4:47 AM EDTLakeshore Flood AdvisoryGRR22 hr
Sep 3, 2:21 PM EDTSpecial Weather StatementGRR54 min
Sep 5, 3:43 PM EDTBeach Hazards StatementGRR52 hr
Sep 5, 5:07 PM EDTBeach Hazards StatementGRR4 hr
Sep 6, 9:38 PM EDTSevere Thunderstorm WatchSPC5 hr
Sep 7, 12:20 AM EDTMesoscale DiscussionSPC115 min
Sep 13, 4:00 AM EDTBeach Hazards StatementGRR12 hr
Sep 14, 3:14 PM EDTBeach Hazards StatementGRR50 hr
Sep 18, 9:03 AM EDTFrost AdvisoryGRR24 hr
Sep 25, 12:45 PM EDTBeach Hazards StatementGRR51 hr
Oct 2, 11:16 AM EDTFrost AdvisoryGRR21 hr
Oct 4, 4:03 AM EDTFrost AdvisoryGRR29 hr
Oct 12, 3:01 PM EDTSpecial Weather StatementGRR3 hr
Oct 16, 3:54 PM EDTFrost AdvisoryGRR16 hr
Oct 16, 3:54 PM EDTWind AdvisoryGRR34 hr
Oct 16, 4:50 PM EDTSpecial Weather StatementGRR115 min
Oct 16, 4:58 PM EDTSpecial Weather StatementGRR2 hr
Oct 16, 7:47 PM EDTSpecial Weather StatementGRR3 hr
Oct 17, 11:26 AM EDTLakeshore Flood AdvisoryGRR17 hr
Oct 30, 2:47 PM EDTLakeshore Flood WarningGRR58 hr
Oct 31, 4:29 AM EDTWind AdvisoryGRR40 hr
Nov 9, 11:44 AM ESTLakeshore Flood StatementGRR12 hr
Nov 10, 11:36 AM ESTWind AdvisoryGRR17 hr
Nov 10, 7:04 PM ESTMesoscale DiscussionSPC116 min
Nov 10, 7:33 PM ESTSevere Thunderstorm WatchSPC4 hr
Nov 10, 7:42 PM ESTSevere Thunderstorm WarningGRR70 min
Nov 13, 5:20 PM ESTLakeshore Flood WatchGRR17 hr
Nov 13, 5:25 PM ESTHigh Wind WatchGRR10 hr
Nov 14, 3:27 AM ESTHigh Wind WarningGRR42 hr
Nov 14, 9:50 AM ESTLakeshore Flood WarningGRR39 hr
Nov 15, 9:53 PM ESTWind AdvisoryGRR6 hr
Nov 19, 3:33 AM ESTWind AdvisoryGRR13 hr
Nov 25, 3:49 PM ESTDense Fog AdvisoryGRR12 hr
Dec 10, 1:06 AM ESTFreezing Fog AdvisoryGRR8 hr
Dec 23, 3:59 AM ESTWinter Weather AdvisoryGRR59 hr
Dec 28, 3:28 PM ESTWinter Weather AdvisoryGRR44 hr
Dec 29, 8:50 PM ESTMesoscale DiscussionSPC4 hr
Dec 30, 2:15 AM ESTMesoscale DiscussionSPC6 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 archive20192021

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.