Last Frost Day

Frost history / Donora 1 Sw, PA

Donora 1 Sw, PA: frost dates by year

Last spring and first fall frost at NOAA station USC00362190, 1951 to 2017, measured from daily minimum temperatures.

Elevation 762 ft, 40.164, -79.869. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 27Oct 20
EarliestApr 6 (2011)Sep 29 (1961)
LatestMay 30 (1961)Nov 12 (2016)
Trendlittle change (less than half a day per decade)little change (less than half a day per decade)
Years with data6264

At 28°F (hard freeze) the median last spring date is Apr 12 and the median first fall date is Nov 3.

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 30Jun 141960197019801990200020101951: Apr 201952: Apr 91953: Apr 211954: Apr 91955: Apr 81956: May 51957: May 51958: Apr 301959: Apr 141960: May 21961: May 301962: Apr 211963: May 21964: Apr 161965: Apr 171967: Apr 291968: May 61969: Apr 201971: May 11973: May 51974: May 81975: Apr 271976: May 121977: May 111978: May 21979: Apr 301980: May 91981: May 221982: Apr 301983: May 121984: May 171985: Apr 171986: May 41987: Apr 291988: May 11989: May 41990: Apr 191991: Apr 121992: Apr 131994: Apr 241995: Apr 161996: May 141997: Apr 211998: Apr 121999: Apr 252000: Apr 272001: Apr 192002: May 212003: Apr 252004: May 42005: May 52006: Apr 262007: Apr 142008: Apr 162009: Apr 132010: May 112011: Apr 62012: Apr 242013: May 142015: Apr 242016: Apr 152017: Apr 10

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 11Nov 261960197019801990200020101951: Nov 31952: Oct 211953: Nov 51954: Nov 11955: Oct 251956: Nov 111957: Oct 121958: Oct 61959: Oct 191960: Oct 211961: Sep 291962: Oct 251963: Oct 301964: Oct 61965: Oct 51967: Oct 201968: Oct 311969: Oct 151971: Nov 41972: Oct 101973: Nov 41974: Oct 31975: Oct 31976: Oct 181977: Nov 111978: Oct 181979: Oct 151980: Oct 231981: Oct 101982: Oct 181983: Oct 171984: Nov 31985: Oct 291986: Oct 201987: Oct 91988: Oct 121989: Oct 51990: Oct 201991: Oct 81992: Oct 181993: Oct 111994: Oct 281995: Oct 261996: Nov 21997: Oct 211998: Nov 41999: Oct 282000: Oct 292001: Oct 82002: Nov 22003: Oct 32004: Nov 92005: Oct 302006: Oct 152007: Oct 292008: Oct 192009: Oct 192010: Oct 302011: Oct 162012: Oct 82013: Oct 252014: Nov 32015: Oct 182016: Nov 12

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
2017Apr 10no dataApr 9no data
2016Apr 15Nov 12Apr 13Nov 12
2015Apr 24Oct 18Apr 2Nov 9
2014no dataNov 3no dataNov 3
2013May 14Oct 25Apr 21Nov 4
2012Apr 24Oct 8Mar 27Nov 6
2011Apr 6Oct 16Mar 30Nov 2
2010May 11Oct 30May 11Nov 2
2009Apr 13Oct 19Apr 12Dec 5
2008Apr 16Oct 19Mar 30Oct 30
2007Apr 14Oct 29Apr 10Nov 8
2006Apr 26Oct 15Mar 28Nov 3
2005May 5Oct 30May 5Nov 18
2004May 4Nov 9Apr 7Nov 10
2003Apr 25Oct 3Apr 1Nov 9
2002May 21Nov 2Apr 8Nov 3
2001Apr 19Oct 8Mar 29Oct 29
2000Apr 27Oct 29Apr 13Nov 6
1999Apr 25Oct 28Mar 28Nov 18
1998Apr 12Nov 4Mar 25Nov 5
1997Apr 21Oct 21Apr 19Oct 23
1996May 14Nov 2Apr 10Nov 4
1995Apr 16Oct 26Apr 15Nov 5
1994Apr 24Oct 28Apr 9Nov 12
1993no dataOct 11no dataNov 8
1992Apr 13Oct 18Apr 13Oct 20
1991Apr 12Oct 8Apr 11Oct 17
1990Apr 19Oct 20Apr 19Oct 27
1989May 4Oct 5May 4Nov 4
1988May 1Oct 12Apr 20Oct 13
1987Apr 29Oct 9Apr 1Oct 26
1986May 4Oct 20Mar 28Nov 13
1985Apr 17Oct 29Apr 11Nov 21
1984May 17Nov 3Apr 2Nov 3
1983May 12Oct 17May 12Oct 30
1982Apr 30Oct 18Apr 23Oct 25
1981May 22Oct 10May 4Oct 10
1980May 9Oct 23Apr 17Oct 30
1979Apr 30Oct 15Apr 30Oct 27
1978May 2Oct 18May 2Dec 1
1977May 11Nov 11Apr 10Nov 13
1976May 12Oct 18Apr 29Oct 18
1975Apr 27Oct 3Apr 16Oct 31
1974May 8Oct 3Apr 25Oct 19
1973May 5Nov 4Apr 15Nov 6
1972no dataOct 10no dataOct 20
1971May 1Nov 4Apr 18Nov 4
1969Apr 20Oct 15Apr 1Oct 23
1968May 6Oct 31Apr 6Oct 31
1967Apr 29Oct 20Apr 12Oct 29
1965Apr 17Oct 5Apr 14Oct 6
1964Apr 16Oct 6Apr 5Oct 7
1963May 2Oct 30Apr 16Nov 25
1962Apr 21Oct 25Apr 17Oct 26
1961May 30Sep 29May 4Oct 28
1960May 2Oct 21Apr 11Oct 26
1959Apr 14Oct 19Apr 14Oct 19
1958Apr 30Oct 6Apr 9Nov 23
1957May 5Oct 12Apr 15Nov 7
1956May 5Nov 11Apr 21Nov 17
1955Apr 8Oct 25Mar 31Nov 10
1954Apr 9Nov 1Apr 9Nov 1
1953Apr 21Nov 5Apr 19Nov 6
1952Apr 9Oct 21Mar 28Oct 21
1951Apr 20Nov 3Mar 27Nov 3

"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.