Alert archive / Massachusetts / Nantucket County

Weather alerts in Nantucket County, Massachusetts, 2019

100 weather alerts in 2019, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Nantucket County and its neighbors

Each county as a circle sized by its count in 2019. Tap one for its archive.

Alerts
100
Warnings
17
Watches
15
Advisories
49
Busiest month
October22 alerts
Busiest day
August 8, 20194 alerts

Over time

By month

Warning verification

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

Nantucket County, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings40100%10%
Flash flood warnings00

Each office's whole area, 2019

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Boston/Norton, MA: tornado warnings13285%786%23 min
NWS Boston/Norton, MA: severe thunderstorm warnings1206843%33663%23 min
NWS Boston/Norton, MA: flash flood warnings12192%1100%47 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 8, 6:01 PM ESTDense Fog AdvisoryBOX10 hr
Jan 9, 4:17 AM ESTDense Fog AdvisoryBOX3 hr
Jan 9, 4:17 AM ESTWind AdvisoryBOX12 hr
Jan 17, 1:53 PM ESTCoastal Flood WatchBOX25 hr
Jan 18, 3:02 PM ESTCoastal Flood AdvisoryBOX45 hr
Jan 19, 3:38 PM ESTWind AdvisoryBOX20 hr
Jan 20, 10:57 AM ESTSpecial Weather StatementBOX63 min
Jan 20, 11:16 AM ESTHigh Wind WarningBOX4 hr
Jan 20, 3:20 PM ESTCoastal Flood StatementBOX21 hr
Jan 23, 3:53 AM ESTHigh Wind WatchBOX11 hr
Jan 23, 3:08 PM ESTHigh Wind WarningBOX26 hr
Jan 24, 5:07 PM ESTWind AdvisoryBOX113 min
Jan 29, 4:11 AM ESTHigh Wind WatchBOX23 hr
Jan 30, 3:21 AM ESTHigh Wind WarningBOX19 hr
Feb 4, 9:55 PM ESTDense Fog AdvisoryBOX9 hr
Feb 8, 3:29 AM ESTWind AdvisoryBOX35 hr
Feb 17, 3:48 AM ESTWinter Weather AdvisoryBOX35 hr
Feb 23, 3:37 AM ESTHigh Wind WatchBOX25 hr
Feb 24, 4:07 AM ESTHigh Wind WarningBOX39 hr
Feb 25, 7:01 PM ESTWind AdvisoryBOX20 hr
Feb 26, 3:34 PM ESTWinter Weather AdvisoryBOX42 hr
Mar 22, 3:16 PM EDTWind AdvisoryBOX24 hr
Apr 2, 2:54 PM EDTWind AdvisoryBOX21 hr
Apr 4, 4:12 AM EDTRed Flag WarningBOX15 hr
Apr 13, 7:16 PM EDTDense Fog AdvisoryBOX14 hr
Apr 14, 3:00 AM EDTWind AdvisoryBOX49 hr
Apr 14, 9:05 PM EDTDense Fog AdvisoryBOX9 hr
May 13, 4:36 PM EDTCoastal Flood StatementBOX17 hr
May 24, 8:44 AM EDTWind AdvisoryBOX12 hr
Jun 1, 4:10 AM EDTDense Fog AdvisoryBOX5 hr
Jun 1, 11:12 PM EDTDense Fog AdvisoryBOX9 hr
Jun 20, 4:00 PM EDTDense Fog AdvisoryBOX17 hr
Jun 22, 2:44 PM EDTSpecial Weather StatementBOX46 min
Jun 22, 3:35 PM EDTSpecial Weather StatementBOX40 min
Jun 25, 7:55 AM EDTDense Fog AdvisoryBOX3 hr
Jun 30, 4:59 PM EDTSevere Thunderstorm WarningBOX27 min
Jul 5, 11:45 PM EDTDense Fog AdvisoryBOX7 hr
Jul 11, 1:48 AM EDTDense Fog AdvisoryBOX7 hr
Jul 12, 8:25 AM EDTSpecial Weather StatementBOX35 min
Jul 23, 3:27 AM EDTFlash Flood WatchBOX10 hr
Jul 31, 1:17 PM EDTSevere Thunderstorm WatchSPC7 hr
Aug 8, 3:48 AM EDTSevere Thunderstorm WarningBOX42 min
Aug 8, 4:25 AM EDTSevere Thunderstorm WarningBOX65 min
Aug 8, 5:05 AM EDTSpecial Weather StatementBOX25 min
Aug 8, 5:10 AM EDTSevere Thunderstorm WarningBOX21 min
Aug 13, 3:01 PM EDTSpecial Weather StatementBOX89 min
Aug 13, 3:44 PM EDTAreal Flood WarningBOX2 hr
Aug 18, 3:03 AM EDTDense Fog AdvisoryBOX6 hr
Aug 21, 10:06 AM EDTSpecial Weather StatementBOX84 min
Aug 21, 1:53 PM EDTSevere Thunderstorm WatchSPC7 hr
Aug 26, 11:26 AM EDTRip Current StatementBOX7 hr
Aug 27, 2:55 AM EDTRip Current StatementBOX15 hr
Aug 28, 2:53 AM EDTFlash Flood WatchBOX28 hr
Sep 5, 5:00 AM EDTTropical Storm WatchBOX12 hr
Sep 5, 5:04 PM EDTTropical Storm WarningBOX42 hr
Sep 6, 4:54 AM EDTHigh Surf AdvisoryBOX47 hr
Sep 8, 3:36 AM EDTRip Current StatementBOX13 hr
Sep 18, 3:51 AM EDTRip Current StatementBOX20 hr
Sep 18, 3:34 PM EDTHigh Surf AdvisoryBOX53 hr
Sep 21, 3:42 AM EDTRip Current StatementBOX16 hr
Sep 22, 4:31 PM EDTRip Current StatementBOX3 days
Sep 29, 3:53 AM EDTRip Current StatementBOX4 days
Oct 8, 2:48 PM EDTCoastal Flood WatchBOX37 hr
Oct 8, 3:57 PM EDTHigh Wind WatchBOX11 hr
Oct 9, 3:16 AM EDTHigh Wind WarningBOX42 hr
Oct 9, 3:16 AM EDTWind AdvisoryBOX69 hr
Oct 9, 3:28 AM EDTCoastal Flood AdvisoryBOX33 hr
Oct 9, 3:36 AM EDTFlood WatchBOX42 hr
Oct 10, 3:30 AM EDTCoastal Flood WarningBOX22 hr
Oct 11, 2:43 AM EDTCoastal Flood AdvisoryBOX10 hr
Oct 11, 3:58 PM EDTCoastal Flood AdvisoryBOX10 hr
Oct 16, 4:23 AM EDTHigh Wind WatchBOX11 hr
Oct 16, 4:23 AM EDTWind AdvisoryBOX38 hr
Oct 16, 3:46 PM EDTHigh Wind WarningBOX14 hr
Oct 17, 8:14 AM EDTHigh Wind WarningBOX10 hr
Oct 17, 6:20 PM EDTWind AdvisoryBOX3 hr
Oct 23, 6:35 AM EDTDense Fog AdvisoryBOX2 hr
Oct 26, 3:40 PM EDTWind AdvisoryBOX30 hr
Oct 27, 4:22 PM EDTCoastal Flood AdvisoryBOX23 hr
Oct 28, 4:30 PM EDTCoastal Flood AdvisoryBOX10 hr
Oct 29, 8:02 AM EDTCoastal Flood StatementBOX7 hr
Oct 30, 3:42 AM EDTHigh Wind WatchBOX24 hr
Oct 30, 3:34 PM EDTWind AdvisoryBOX47 hr
Oct 31, 4:08 AM EDTHigh Wind WarningBOX27 hr
Nov 17, 3:17 AM ESTWind AdvisoryBOX38 hr
Nov 17, 3:21 AM ESTCoastal Flood AdvisoryBOX38 hr
Nov 23, 3:48 PM ESTWind AdvisoryBOX30 hr
Nov 28, 3:04 AM ESTWind AdvisoryBOX21 hr
Nov 29, 4:23 AM ESTCoastal Flood StatementBOX13 hr
Dec 1, 8:22 PM ESTCoastal Flood AdvisoryBOX21 hr
Dec 2, 4:24 AM ESTWind AdvisoryBOX9 hr
Dec 2, 7:33 PM ESTWind AdvisoryBOX14 hr
Dec 3, 3:11 AM ESTCoastal Flood AdvisoryBOX6 hr
Dec 13, 2:46 AM ESTFlood WatchBOX31 hr
Dec 13, 2:49 AM ESTWind AdvisoryBOX34 hr
Dec 13, 4:40 PM ESTCoastal Flood StatementBOX21 hr
Dec 14, 2:09 AM ESTHigh Wind WarningBOX8 hr
Dec 14, 3:30 PM ESTWind AdvisoryBOX28 hr
Dec 14, 4:04 PM ESTDense Fog AdvisoryBOX2 hr
Dec 18, 4:12 AM ESTWind AdvisoryBOX29 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 archive20182020

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.