Alert archive / Pennsylvania

Weather alerts in Tioga County, Pennsylvania

2,938 weather alerts since 1986, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Tioga County and its neighbors

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

Alerts
2,938
Warnings
684
Watches
474
Advisories
695
Busiest year
2011218 alerts
Average year
75over 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 Tioga County fell inside a tornado warning issued on average 21 minutes before, and 75% of the tornado warnings had no report inside them.

Tornado warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
200910100%0
2010220%1100%32 min
201120100%10%
201210100%0
20185180%10%
2019110%1100%10 min
202320100%0
202420100%0
Share of tornado reports inside a tornado warning, by year.

Severe thunderstorm warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
20087271%367%28 min
200910730%1675%33 min
201013931%0
201122768%863%19 min
2012221818%1182%29 min
2013201240%667%18 min
201412742%0
201510460%5100%43 min
20164250%0
201711645%11100%33 min
201810640%1479%20 min
201914843%1493%28 min
20207443%3100%8 min
2021131115%1486%22 min
20226517%888%13 min
20235340%5100%21 min
2024181139%1593%26 min
202512650%7100%18 min

Flash flood warnings by year

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
201010100%0
20116267%30%
2012110%3100%58 min
201610100%0
2017110%2100%131 min
201830100%0
202010100%0
20215420%667%54 min
2024440%11100%102 min
202520100%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
Sep 9, 8:10 PM EDTSevere Thunderstorm WarningCTP35 min
Sep 9, 7:33 PM EDTSevere Thunderstorm WarningCTP42 min
Sep 3, 12:23 AM EDTSevere Thunderstorm WarningCTP61 min
Sep 2, 11:43 PM EDTSevere Thunderstorm WarningCTP41 min
Sep 2, 9:50 PM EDTSevere Thunderstorm WarningCTP40 min
Sep 2, 9:29 PM EDTSevere Thunderstorm WarningCTP16 min
Sep 2, 8:50 PM EDTSevere Thunderstorm WarningCTP55 min
Sep 2, 8:29 PM EDTTornado WarningCTP35 min
Sep 2, 8:22 PM EDTSevere Thunderstorm WarningCTP38 min
Sep 2, 7:56 PM EDTTornado WarningCTP34 min
Sep 1, 5:42 PM EDTSevere Thunderstorm WarningCTP48 min
Sep 1, 5:19 PM EDTTornado WarningCTP26 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.