Alert archive / New Hampshire

Weather alerts in Strafford County, New Hampshire

2,490 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Strafford County and its neighbors

Each county as a circle sized by its count since 1986. Tap one for its archive.

Alerts
2,490
Warnings
605
Watches
427
Advisories
744
Busiest year
2008158 alerts
Average year
66over 38 years on file

Over time

By year

Before late 2005 the archive holds only tornado, severe thunderstorm, flash flood and marine warnings, and from 1997 SPC's watches, so the jump that year is the archive widening, not the weather.

By month of the year

Warning verification

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

From 2008 to 2025, 100% of tornado reports in Strafford County fell inside a tornado warning issued on average 19 minutes before, and 60% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20082150%1100%19 min
201810100%0
2020110%0
202310100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008241442%1486%15 min
20098538%0
201010820%1493%17 min
2011191616%8100%20 min
2012181233%580%21 min
2013201810%4100%20 min
2014201620%6100%22 min
201519185%3100%32 min
201610910%9100%25 min
20178713%617%3 min
2018191616%989%47 min
2019880%3100%11 min
2020121017%367%16 min
202115147%475%21 min
202211110%9100%14 min
20238625%978%13 min
202410910%1164%20 min
20255340%30%

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200920100%0
201110100%0
201210100%0
201310100%0
20142150%0
201510100%0
2016110%2100%40 min
201710100%0
201820100%0
2019110%0
2020220%0
20213167%1100%117 min
20237614%0

Years from 2008, the first full year of storm-based warnings. The year still running is on its own page.

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.

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

The latest warnings

The most recent on file, newest first.

IssuedProductOfficeLasted
Aug 8, 4:40 PM EDTSevere Thunderstorm WarningGYX50 min
Aug 3, 7:21 AM EDTFlash Flood WarningGYX4 hr
Jul 16, 3:52 PM EDTSevere Thunderstorm WarningGYX38 min
Jul 16, 3:15 PM EDTSevere Thunderstorm WarningGYX45 min
Jun 30, 1:57 PM EDTExtreme Heat WarningGYX3 days
Jun 26, 4:44 PM EDTSevere Thunderstorm WarningGYX61 min
Jun 18, 4:42 PM EDTSevere Thunderstorm WarningGYX48 min
Jun 18, 4:21 PM EDTSevere Thunderstorm WarningGYX54 min
Apr 14, 7:24 PM EDTSevere Thunderstorm WarningGYX51 min
Feb 22, 1:37 AM ESTWinter Storm WarningGYX44 hr
Feb 19, 12:54 PM ESTWinter Storm WarningGYX42 hr
Jan 24, 12:39 PM ESTWinter Storm WarningGYX60 hr

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive

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.