Alert archive / Maine

Weather alerts in Penobscot County, Maine

3,489 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Penobscot County and its neighbors

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

Alerts
3,489
Warnings
1,015
Watches
415
Advisories
1,371
Busiest year
2013216 alerts
Average year
89over 39 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, 50% of tornado reports in Penobscot County fell inside a tornado warning issued on average 4 minutes before, and 83% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200810100%0
2009110%0
20102150%1100%4 min
201120100%0
201320100%0
2017010%
201810100%0
202010100%0
202520100%0

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
2008211243%1164%17 min
200916850%1100%35 min
2010131023%2343%25 min
2011372241%2186%24 min
201213654%757%27 min
2013543633%3876%22 min
20149278%5100%13 min
2015461959%3474%25 min
2016302420%5788%20 min
2017181044%1984%28 min
201816944%1681%18 min
2019231343%2186%19 min
202011645%888%35 min
202110730%956%19 min
202225484%3100%22 min
202316663%1593%18 min
2024281932%9181%21 min
202516663%1118%33 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20095340%3100%37 min
20102150%250%25 min
20114325%1100%53 min
20125180%475%98 min
20138363%1100%0 min
2014110%367%56 min
201610100%0
201710100%10%
2021220%3100%60 min
20223167%2100%64 min
202320100%70%
20243233%3100%53 min

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 28, 6:40 PM EDTSevere Thunderstorm WarningCAR50 min
Aug 28, 6:09 PM EDTSevere Thunderstorm WarningCAR51 min
Aug 28, 4:42 PM EDTSevere Thunderstorm WarningCAR48 min
Aug 28, 3:44 PM EDTSevere Thunderstorm WarningCAR46 min
Aug 13, 7:33 PM EDTSevere Thunderstorm WarningCAR42 min
Aug 13, 2:48 PM EDTSevere Thunderstorm WarningCAR42 min
Jul 22, 4:01 PM EDTSevere Thunderstorm WarningCAR44 min
Jul 22, 3:59 PM EDTSevere Thunderstorm WarningCAR30 min
Jul 22, 3:27 PM EDTSevere Thunderstorm WarningCAR32 min
Jul 16, 2:21 PM EDTSevere Thunderstorm WarningCAR39 min
Jul 16, 1:55 PM EDTSevere Thunderstorm WarningCAR32 min
Jul 16, 1:43 PM EDTSevere Thunderstorm WarningCAR47 min

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.