Last Frost Day

Frost history / Harrisburg 12WNW, NE

Harrisburg 12WNW, NE: frost dates by year

Last spring and first fall frost at NOAA station USC00253605, 1961 to 2025, measured from daily minimum temperatures.

Elevation 4,550 ft, 41.633, -103.954. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 24Sep 18
EarliestApr 25 (1977)Aug 23 (2015)
LatestJun 19 (2024)Oct 11 (1963)
Trend1.5 days later per decadelittle change (less than half a day per decade)
Years with data6364

At 28°F (hard freeze) the median last spring date is May 8 and the median first fall date is Sep 27.

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)

Apr 15Apr 30May 15May 30Jun 14Jun 291970198019902000201020201962: May 11963: May 221965: May 271966: May 241967: May 171968: May 191969: Jun 141970: May 151971: May 121972: May 301973: May 221974: May 311975: Jun 171976: May 171977: Apr 251978: Jun 21979: May 111980: May 261981: May 141982: May 71983: May 181984: May 81985: Jun 121986: May 241987: May 271988: May 91989: Jun 11990: May 171991: May 131992: Jun 61993: May 111994: Jun 91995: Jun 111996: May 101997: May 191998: Jun 61999: May 132000: May 192001: Jun 152002: May 252003: Jun 82004: Jun 22005: May 282006: Jun 12007: Jun 82008: Jun 122009: May 272010: May 132011: Jun 12012: May 292013: May 222014: Jun 152015: May 212016: May 172017: May 242018: Apr 272019: Jun 102020: May 262021: May 312022: Jun 22023: May 62024: Jun 192025: May 22

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 271970198019902000201020201961: Sep 131962: Sep 91963: Oct 111964: Sep 41965: Sep 161966: Oct 11967: Sep 131968: Sep 41969: Oct 41970: Sep 101971: Sep 191972: Sep 211973: Sep 171974: Sep 31975: Sep 201976: Sep 91977: Sep 181978: Sep 131979: Sep 141980: Sep 221981: Sep 181982: Sep 201983: Sep 181984: Sep 81985: Sep 201986: Sep 271987: Sep 181988: Sep 201989: Sep 121990: Sep 231991: Sep 181992: Sep 101993: Sep 31994: Sep 221995: Sep 201996: Sep 211997: Sep 271998: Oct 61999: Sep 132000: Sep 232001: Sep 92002: Sep 212004: Aug 282005: Sep 162006: Sep 22007: Sep 252008: Sep 292009: Sep 242010: Sep 32011: Sep 42012: Sep 92013: Oct 42014: Sep 122015: Aug 232016: Sep 102017: Sep 62018: Sep 212019: Oct 32020: Sep 82021: Oct 12022: Sep 112023: Sep 252024: Oct 12025: Sep 6

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
2025May 22Sep 6Apr 29Oct 19
2024Jun 19Oct 1May 22Oct 1
2023May 6Sep 25May 2Oct 7
2022Jun 2Sep 11May 25Oct 8
2021May 31Oct 1May 9Oct 14
2020May 26Sep 8May 11Sep 10
2019Jun 10Oct 3May 12Oct 3
2018Apr 27Sep 21Apr 27Sep 26
2017May 24Sep 6May 4Oct 3
2016May 17Sep 10May 12Sep 10
2015May 21Aug 23May 12Oct 17
2014Jun 15Sep 12May 13Sep 13
2013May 22Oct 4May 5Oct 16
2012May 29Sep 9May 20Oct 4
2011Jun 1Sep 4May 3Oct 19
2010May 13Sep 3May 13Sep 3
2009May 27Sep 24May 9Sep 28
2008Jun 12Sep 29May 11Sep 29
2007Jun 8Sep 25May 24Oct 10
2006Jun 1Sep 2May 16Sep 19
2005May 28Sep 16May 3Oct 6
2004Jun 2Aug 28May 14Oct 18
2003Jun 8no dataMay 20no data
2002May 25Sep 21May 23Sep 22
2001Jun 15Sep 9Apr 24Sep 9
2000May 19Sep 23May 13Sep 25
1999May 13Sep 13May 12Sep 13
1998Jun 6Oct 6May 2Oct 13
1997May 19Sep 27May 15Oct 9
1996May 10Sep 21May 5Sep 26
1995Jun 11Sep 20May 4Sep 22
1994Jun 9Sep 22Apr 30Oct 23
1993May 11Sep 3May 11Sep 14
1992Jun 6Sep 10Apr 26Sep 18
1991May 13Sep 18May 6Sep 19
1990May 17Sep 23May 10Oct 8
1989Jun 1Sep 12May 6Sep 13
1988May 9Sep 20May 4Sep 20
1987May 27Sep 18Apr 21Sep 21
1986May 24Sep 27May 1Sep 30
1985Jun 12Sep 20Jun 12Sep 24
1984May 8Sep 8May 8Sep 25
1983May 18Sep 18May 13Sep 20
1982May 7Sep 20May 7Oct 7
1981May 14Sep 18Apr 14Oct 1
1980May 26Sep 22Apr 25Oct 3
1979May 11Sep 14May 11Oct 4
1978Jun 2Sep 13May 13Sep 30
1977Apr 25Sep 18Apr 21Sep 24
1976May 17Sep 9Apr 25Sep 28
1975Jun 17Sep 20Apr 30Sep 20
1974May 31Sep 3May 14Sep 21
1973May 22Sep 17May 14Sep 17
1972May 30Sep 21May 3Sep 21
1971May 12Sep 19May 7Sep 19
1970May 15Sep 10May 2Sep 26
1969Jun 14Oct 4Jun 14Oct 5
1968May 19Sep 4May 11Oct 6
1967May 17Sep 13May 4Sep 27
1966May 24Oct 1May 12Oct 1
1965May 27Sep 16Apr 28Sep 16
1964no dataSep 4no dataSep 20
1963May 22Oct 11Apr 25Oct 27
1962May 1Sep 9May 1Sep 9
1961no dataSep 13no dataSep 15

"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.