Alert archive / North Dakota / Griggs County

Weather alerts in Griggs County, North Dakota, 2015

125 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Griggs County and its neighbors

Each county as a circle sized by its count in 2015. Tap one for its archive.

Alerts
125
Warnings
27
Watches
21
Advisories
54
Busiest month
July24 alerts
Busiest day
June 20, 20155 alerts

Over time

By month

Warning verification

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

1 of 2 tornado warnings covering Griggs County in 2015 had a tornado report inside them; 1 of 1 tornado reports fell inside a warning, on average 2 minutes after it went out.

Griggs County, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings2150%1100%2 min
Severe thunderstorm warnings9811%333%16 min
Flash flood warnings00

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Grand Forks, ND: tornado warnings521473%5485%22 min
NWS Grand Forks, ND: severe thunderstorm warnings13310323%32469%27 min
NWS Grand Forks, ND: flash flood warnings110%2100%253 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, 4:17 AM CSTWinter Weather AdvisoryFGF35 hr
Jan 3, 2:49 PM CSTWind Chill WarningFGF45 hr
Jan 5, 3:13 PM CSTWind Chill AdvisoryFGF33 hr
Jan 6, 3:41 AM CSTWind Chill WarningFGF32 hr
Jan 8, 3:06 AM CSTWinter Weather AdvisoryFGF15 hr
Jan 8, 3:33 PM CSTWind Chill AdvisoryFGF20 hr
Jan 9, 3:30 PM CSTWind Chill AdvisoryFGF21 hr
Jan 11, 2:11 PM CSTWind Chill AdvisoryFGF20 hr
Jan 12, 3:11 PM CSTWind Chill AdvisoryFGF19 hr
Jan 17, 3:59 AM CSTWind AdvisoryFGF9 hr
Jan 28, 4:00 AM CSTDense Fog AdvisoryFGF8 hr
Jan 31, 3:16 PM CSTWind Chill AdvisoryFGF20 hr
Feb 9, 3:19 PM CSTWinter Weather AdvisoryFGF37 hr
Feb 10, 11:15 AM CSTWinter Weather AdvisoryFGF17 hr
Feb 11, 4:07 AM CSTWind Chill AdvisoryFGF32 hr
Feb 13, 3:15 PM CSTWind Chill AdvisoryFGF23 hr
Feb 15, 1:25 AM CSTWinter Weather AdvisoryFGF8 hr
Feb 16, 3:29 PM CSTWind Chill AdvisoryFGF45 hr
Feb 17, 3:32 AM CSTWind Chill AdvisoryFGF55 hr
Feb 20, 2:50 PM CSTWind Chill AdvisoryFGF30 hr
Feb 21, 3:49 AM CSTWind Chill WarningFGF32 hr
Feb 22, 11:40 AM CSTWind Chill AdvisoryFGF21 hr
Feb 25, 3:12 PM CSTWind Chill AdvisoryFGF20 hr
Feb 26, 2:38 PM CSTWind Chill AdvisoryFGF19 hr
Mar 2, 2:32 PM CSTWind AdvisoryFGF27 hr
Mar 3, 3:28 PM CSTWind Chill AdvisoryFGF21 hr
Mar 4, 3:34 PM CSTWind Chill AdvisoryFGF18 hr
Mar 25, 3:36 AM CDTWind AdvisoryFGF14 hr
Mar 28, 3:33 PM CDTWind AdvisoryFGF27 hr
Mar 31, 3:13 PM CDTFire Weather WatchFGF13 hr
Apr 1, 4:17 AM CDTRed Flag WarningFGF15 hr
Apr 2, 10:32 AM CDTWind AdvisoryFGF8 hr
Apr 11, 3:27 AM CDTRed Flag WarningFGF17 hr
Apr 12, 1:46 PM CDTFire Weather WatchFGF14 hr
Apr 13, 3:37 AM CDTRed Flag WarningFGF16 hr
Apr 13, 1:17 PM CDTWind AdvisoryFGF5 hr
Apr 13, 3:06 PM CDTFire Weather WatchFGF12 hr
Apr 14, 3:31 AM CDTFire Weather WatchFGF24 hr
Apr 14, 3:31 AM CDTRed Flag WarningFGF17 hr
Apr 15, 3:15 AM CDTRed Flag WarningFGF17 hr
Apr 15, 3:38 AM CDTWind AdvisoryFGF15 hr
Apr 15, 3:42 PM CDTSpecial Weather StatementFGF48 min
Apr 15, 4:44 PM CDTSpecial Weather StatementFGF61 min
Apr 19, 3:14 PM CDTFire Weather WatchFGF13 hr
Apr 20, 5:31 AM CDTWind AdvisoryFGF15 hr
Apr 21, 11:17 AM CDTWind AdvisoryFGF8 hr
Apr 29, 2:59 PM CDTRed Flag WarningFGF28 hr
May 1, 3:10 PM CDTFire Weather WatchFGF13 hr
May 2, 4:22 AM CDTRed Flag WarningFGF16 hr
May 2, 3:11 PM CDTSpecial Weather StatementFGF64 min
May 2, 3:54 PM CDTSpecial Weather StatementFGF51 min
May 4, 3:17 PM CDTFire Weather WatchFGF13 hr
May 5, 4:45 AM CDTRed Flag WarningFGF14 hr
May 8, 2:52 PM CDTFrost AdvisoryFGF18 hr
May 16, 8:24 PM CDTSpecial Weather StatementFGF36 min
May 17, 3:58 AM CDTWind AdvisoryFGF31 hr
May 18, 3:21 AM CDTFreeze WarningFGF30 hr
May 19, 2:53 PM CDTFrost AdvisoryFGF17 hr
May 28, 2:35 PM CDTMesoscale DiscussionSPC55 min
May 29, 3:18 PM CDTFrost AdvisoryFGF17 hr
Jun 2, 2:02 AM CDTSpecial Weather StatementFGF28 min
Jun 2, 2:46 PM CDTTornado WatchSPC7 hr
Jun 13, 5:11 PM CDTMesoscale DiscussionSPC94 min
Jun 20, 5:36 PM CDTTornado WarningFGF39 min
Jun 20, 6:13 PM CDTSevere Thunderstorm WarningFGF31 min
Jun 20, 6:25 PM CDTSevere Thunderstorm WarningFGF50 min
Jun 20, 6:33 PM CDTSevere Thunderstorm WarningFGF42 min
Jun 20, 6:58 PM CDTTornado WarningFGF47 min
Jun 21, 8:32 PM CDTMesoscale DiscussionSPC88 min
Jun 21, 10:29 PM CDTSevere Thunderstorm WarningFGF61 min
Jun 21, 10:41 PM CDTSevere Thunderstorm WatchSPC6 hr
Jun 27, 2:01 PM CDTMesoscale DiscussionSPC119 min
Jun 27, 2:42 PM CDTTornado WatchSPC7 hr
Jul 4, 6:49 PM CDTMesoscale DiscussionSPC116 min
Jul 5, 9:54 AM CDTMesoscale DiscussionSPC96 min
Jul 5, 10:18 AM CDTSevere Thunderstorm WarningFGF57 min
Jul 5, 10:40 AM CDTSevere Thunderstorm WatchSPC7 hr
Jul 5, 10:58 AM CDTSevere Thunderstorm WarningFGF62 min
Jul 5, 11:33 AM CDTSevere Thunderstorm WarningFGF38 min
Jul 11, 5:00 PM CDTMesoscale DiscussionSPC60 min
Jul 11, 5:40 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 11, 9:04 PM CDTMesoscale DiscussionSPC86 min
Jul 12, 2:54 PM CDTMesoscale DiscussionSPC96 min
Jul 12, 3:06 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 12, 5:53 PM CDTMesoscale DiscussionSPC97 min
Jul 12, 8:16 PM CDTMesoscale DiscussionSPC59 min
Jul 17, 1:10 PM CDTMesoscale DiscussionSPC2 hr
Jul 17, 3:43 PM CDTSevere Thunderstorm WatchSPC7 hr
Jul 17, 6:02 PM CDTMesoscale DiscussionSPC118 min
Jul 23, 3:58 PM CDTSevere Thunderstorm WatchSPC11 hr
Jul 23, 9:54 PM CDTSevere Thunderstorm WarningFGF66 min
Jul 23, 10:28 PM CDTMesoscale DiscussionSPC32 min
Jul 23, 10:40 PM CDTSevere Thunderstorm WarningFGF65 min
Jul 24, 12:41 AM CDTMesoscale DiscussionSPC2 hr
Jul 25, 4:30 PM CDTMesoscale DiscussionSPC3 hr
Jul 27, 10:49 PM CDTSevere Thunderstorm WatchSPC5 hr
Jul 28, 4:02 AM CDTWind AdvisoryFGF39 hr
Aug 15, 3:36 AM CDTHeat AdvisoryFGF15 hr
Aug 15, 3:38 PM CDTMesoscale DiscussionSPC67 min
Aug 15, 6:13 PM CDTSevere Thunderstorm WatchSPC6 hr
Aug 22, 9:42 AM CDTWind AdvisoryFGF33 hr
Sep 10, 2:54 PM CDTFrost AdvisoryFGF18 hr
Sep 25, 3:44 AM CDTDense Fog AdvisoryFGF7 hr
Sep 26, 3:50 AM CDTWind AdvisoryFGF15 hr
Sep 28, 2:29 PM CDTFrost AdvisoryFGF18 hr
Oct 6, 3:41 PM CDTFrost AdvisoryFGF16 hr
Oct 8, 9:53 PM CDTFrost AdvisoryFGF10 hr
Oct 9, 3:03 AM CDTDense Fog AdvisoryFGF7 hr
Oct 10, 3:38 PM CDTHigh Wind WatchFGF19 hr
Oct 11, 10:41 AM CDTHigh Wind WarningFGF29 hr
Oct 15, 3:36 AM CDTFreeze WarningFGF30 hr
Oct 28, 4:04 AM CDTWind AdvisoryFGF19 hr
Oct 31, 3:40 AM CDTWind AdvisoryFGF15 hr
Nov 3, 2:46 PM CSTDense Fog AdvisoryFGF31 hr
Nov 10, 2:33 AM CSTDense Fog AdvisoryFGF9 hr
Nov 11, 3:06 AM CSTHigh Wind WatchFGF11 hr
Nov 11, 2:10 PM CSTWind AdvisoryFGF27 hr
Nov 17, 11:36 AM CSTHigh Wind WatchFGF16 hr
Nov 18, 3:50 AM CSTHigh Wind WarningFGF20 hr
Nov 18, 3:50 AM CSTWind AdvisoryFGF40 hr
Nov 30, 4:23 AM CSTWinter Weather AdvisoryFGF35 hr
Dec 12, 5:03 PM CSTDense Fog AdvisoryFGF42 hr
Dec 14, 4:05 AM CSTWinter Storm WatchFGF35 hr
Dec 15, 2:43 PM CSTWinter Storm WarningFGF28 hr
Dec 22, 3:29 AM CSTWinter Weather AdvisoryFGF27 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 archive20142016

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.