Last Frost Day

Frost history / Williamsport 2, PA

Williamsport 2, PA: frost dates by year

Last spring and first fall frost at NOAA station USC00369735, 1999 to 2025, measured from daily minimum temperatures.

Elevation 525 ft, 41.249, -76.983. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 29Oct 25
EarliestApr 9 (2017)Oct 3 (2003)
LatestMay 22 (2002)Nov 7 (2014)
Trend2.4 days earlier per decade6.1 days later per decade
Years with data2526

At 28°F (hard freeze) the median last spring date is Apr 10 and the median first fall date is Nov 5.

The trend is a straight-line fit through the years with a freeze. A positive spring trend means the last frost now comes later. Short or patchy records give noisy trends.

Chart

Last spring frost (32°F)

Mar 31Apr 15Apr 30May 15May 302000201020202000: Apr 132001: Apr 292002: May 222003: Apr 142005: May 132006: Apr 292007: May 142008: May 12009: May 192010: May 112011: Apr 222012: May 172013: May 142014: Apr 202015: Apr 262016: Apr 142017: Apr 92018: Apr 232019: Apr 292020: May 132021: Apr 232022: Apr 302023: May 182024: Apr 232025: Apr 18

First fall frost (32°F)

Sep 27Oct 12Oct 27Nov 11Nov 262000201020201999: Oct 72000: Oct 92001: Oct 82002: Oct 152003: Oct 32004: Nov 42005: Oct 282006: Oct 132007: Oct 292008: Oct 192009: Oct 142010: Oct 232011: Oct 282013: Oct 282014: Nov 72015: Oct 182016: Oct 262017: Nov 12018: Oct 192019: Nov 22020: Nov 42021: Nov 32022: Oct 212023: Oct 312024: Oct 272025: Oct 10

Dots are single years. The gray line is the median, the green line the fitted trend.

Year by year

YearLast spring 32°FFirst fall 32°FLast spring 28°FFirst fall 28°F
2025Apr 18Oct 10Apr 9Oct 28
2024Apr 23Oct 27Mar 25Nov 13
2023May 18Oct 31Mar 31Nov 2
2022Apr 30Oct 21Apr 18Nov 14
2021Apr 23Nov 3Apr 3Nov 5
2020May 13Nov 4Apr 19Nov 17
2019Apr 29Nov 2Apr 3Nov 4
2018Apr 23Oct 19Apr 11Nov 11
2017Apr 9Nov 1Mar 23Nov 8
2016Apr 14Oct 26Apr 10Nov 12
2015Apr 26Oct 18Apr 1Nov 21
2014Apr 20Nov 7Apr 17Nov 14
2013May 14Oct 28Apr 21Nov 3
2012May 17no dataMar 27no data
2011Apr 22Oct 28Apr 6Nov 5
2010May 11Oct 23Mar 27Nov 2
2009May 19Oct 14Apr 13Oct 19
2008May 1Oct 19Apr 15Oct 20
2007May 14Oct 29Apr 14Nov 2
2006Apr 29Oct 13Apr 9Oct 14
2005May 13Oct 28Apr 13Nov 12
2004no dataNov 4no dataNov 9
2003Apr 14Oct 3Apr 14Oct 3
2002May 22Oct 15Apr 7Oct 29
2001Apr 29Oct 8Apr 19Oct 9
2000Apr 13Oct 9Apr 13Nov 6
1999no dataOct 7no dataNov 5

"none" means the station recorded no freeze at that threshold in that half of the year. "no data" means more than 10% of the season's daily readings were missing. Years with no usable data are left out. See the methodology for the rules, and the ZIP lookup for 1991 to 2020 frost probabilities.