All-time weather records — Williamsport, PA

Record high
104.0°F
July 22, 2011
Record low
-11.0°F
January 17, 2009
Wettest day
5.56 in
September 7, 1999

Climate change signal in Williamsport

40.2%

of Williamsport's all-time daily heat records were set in the last decade (147 of 366 records since 2015).

32.8%

of all-time daily cold records were set in the last decade (120 of 366 records since 2015).

If records were spread evenly across the station's history, you'd expect roughly 5% per decade. Decade-by-decade, here's where each record-breaking day was set:

Decade Heat records set # Cold records set #
1990s
10
14
2000s
151
181
2010s
121
111
2020s
84
60

Records are the all-time daily extremes that are still standing — each daily record can only be held by one year. The station's earliest hot record was set in 1999, the latest in 2025. Period of observation: 1997-2026.

Records by month

Month Hottest day Coldest day Wettest day
January 66.9°F — Jan 8, 2008 -11.0°F — Jan 17, 2009 2.90 in — Jan 25, 2010
February 75.0°F — Feb 24, 2017 -7.1°F — Feb 24, 2015 1.90 in — Feb 16, 2016
March 84.0°F — Mar 27, 2007 1.9°F — Mar 7, 2003 2.33 in — Mar 10, 2011
April 95.0°F — Apr 27, 2009 19.9°F — Apr 7, 2002 2.34 in — Apr 16, 2018
May 98.1°F — May 30, 2006 28.9°F — May 3, 2005 2.67 in — May 16, 2014
June 98.1°F — Jun 24, 2025 39.0°F — Jun 1, 2009 2.99 in — Jun 18, 2017
July 104.0°F — Jul 22, 2011 46.0°F — Jul 3, 2007 2.54 in — Jul 24, 2023
August 100.0°F — Aug 2, 2007 44.1°F — Aug 21, 2000 5.14 in — Aug 9, 2024
September 99.0°F — Sep 10, 2002 33.1°F — Sep 29, 2000 5.56 in — Sep 7, 1999
October 90.0°F — Oct 4, 2007 26.1°F — Oct 29, 2001 3.74 in — Oct 29, 2017
November 78.1°F — Nov 4, 2003 10.9°F — Nov 23, 2018 3.58 in — Nov 29, 2005
December 69.1°F — Dec 1, 2006 -2.9°F — Dec 23, 2000 3.06 in — Dec 1, 2010

Click a month to see every daily record for that month in Williamsport.