Frost history / Phila Franklin Inst, PA
Phila Franklin Inst, PA: frost dates by year
Last spring and first fall frost at NOAA station USC00366886, 1993 to 2025, measured from daily minimum temperatures.
Elevation 60 ft, 39.959, -75.173. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Mar 29 | Nov 22 |
| Earliest | Mar 14 (2003) | Oct 25 (2008) |
| Latest | Apr 26 (2015) | Dec 22 (2001) |
| Trend | 1.9 days later per decade | 0.6 days later per decade |
| Years with data | 29 | 32 |
At 28°F (hard freeze) the median last spring date is Mar 16 and the median first fall date is Nov 30.
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)
First fall frost (32°F)
Dots are single years. The gray line is the median, the green line the fitted trend.
Year by year
| Year | Last spring 32°F | First fall 32°F | Last spring 28°F | First fall 28°F |
|---|---|---|---|---|
| 2025 | Apr 9 | Nov 11 | Mar 3 | Dec 5 |
| 2024 | no data | Nov 30 | no data | Dec 1 |
| 2023 | Mar 20 | Nov 25 | Mar 19 | Nov 29 |
| 2022 | Mar 30 | Nov 18 | Mar 29 | Nov 21 |
| 2021 | Apr 4 | Nov 24 | Mar 16 | Dec 21 |
| 2020 | no data | Nov 19 | no data | Dec 16 |
| 2019 | Apr 1 | Nov 9 | Mar 8 | Nov 9 |
| 2018 | Apr 10 | Nov 11 | Feb 13 | Nov 23 |
| 2017 | Mar 24 | no data | Mar 24 | no data |
| 2016 | Apr 11 | Dec 9 | Mar 4 | Dec 11 |
| 2015 | Apr 26 | Dec 20 | Mar 24 | none |
| 2014 | Mar 28 | Nov 15 | Mar 27 | Nov 18 |
| 2013 | Apr 4 | Nov 13 | Feb 22 | Nov 24 |
| 2012 | Mar 27 | Dec 6 | Mar 6 | none |
| 2011 | Mar 29 | Dec 10 | Mar 28 | Dec 18 |
| 2010 | Mar 27 | Nov 29 | Feb 27 | Dec 9 |
| 2009 | Mar 23 | Dec 6 | Mar 23 | Dec 11 |
| 2008 | Mar 29 | Oct 25 | Mar 2 | Nov 19 |
| 2007 | Apr 9 | Nov 23 | Mar 18 | Nov 24 |
| 2006 | Mar 21 | Nov 4 | Mar 20 | Dec 8 |
| 2005 | Mar 15 | Nov 23 | Mar 10 | Nov 24 |
| 2004 | Apr 5 | Nov 14 | Mar 23 | Dec 15 |
| 2003 | Mar 14 | Dec 2 | Mar 11 | Dec 2 |
| 2002 | Mar 23 | Nov 27 | Mar 22 | Nov 28 |
| 2001 | no data | Dec 22 | no data | Dec 27 |
| 2000 | Apr 9 | Nov 20 | Feb 17 | Nov 22 |
| 1999 | Mar 26 | Nov 17 | Mar 12 | Dec 1 |
| 1998 | Mar 22 | Dec 22 | Mar 16 | Dec 22 |
| 1997 | Apr 10 | Nov 16 | Mar 24 | Dec 31 |
| 1996 | Apr 9 | Nov 11 | Mar 12 | Nov 15 |
| 1995 | Apr 6 | Nov 5 | Apr 6 | Nov 30 |
| 1994 | Mar 17 | Nov 24 | Mar 17 | Nov 24 |
| 1993 | no data | Nov 8 | no data | Nov 26 |
"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.