Last Frost Day

Frost history / Hanover, NH

Hanover, NH: frost dates by year

Last spring and first fall frost at NOAA station USC00273850, 1951 to 2024, measured from daily minimum temperatures.

Elevation 584 ft, 43.705, -72.286. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 12Oct 5
EarliestApr 22 (1980)Sep 14 (1963)
LatestJun 8 (1987)Oct 31 (2023)
Trend2.4 days earlier per decade2.5 days later per decade
Years with data7169

At 28°F (hard freeze) the median last spring date is Apr 28 and the median first fall date is Oct 15.

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 1419601970198019902000201020201951: May 191952: May 171953: May 41954: May 271955: May 181956: May 291957: May 191958: Jun 71959: May 181960: May 31961: May 311962: May 131963: May 251964: May 211966: May 141967: May 301968: May 271969: May 271970: May 71971: May 241972: May 131973: May 71974: May 51975: May 91976: May 131977: May 151978: May 61979: May 71980: Apr 221981: May 191982: May 51983: May 191984: May 181985: May 91986: Jun 31987: Jun 81988: May 81989: May 91990: May 121991: Apr 251992: May 261993: Apr 281994: May 41995: May 71996: May 151997: May 111998: Apr 292000: May 32002: May 202003: May 42004: May 82005: May 172006: Apr 302007: May 72008: May 22009: May 192010: May 132011: Apr 222012: Apr 302013: May 152014: May 72015: Apr 252016: May 172017: May 42018: Apr 242019: Apr 292020: May 142021: May 72022: May 92023: May 182024: Apr 27

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 301952: Oct 91953: Sep 231954: Oct 71955: Sep 231956: Sep 211957: Sep 271958: Oct 21959: Sep 171960: Oct 21961: Oct 51962: Sep 211963: Sep 141964: Sep 161965: Sep 281966: Sep 261967: Oct 71968: Oct 61969: Oct 151970: Oct 171971: Oct 131972: Oct 21973: Sep 211974: Sep 241975: Oct 41976: Oct 121977: Oct 71978: Sep 261979: Sep 201981: Oct 11982: Oct 111983: Oct 111984: Sep 271985: Oct 121986: Oct 71987: Sep 261988: Sep 291990: Oct 171991: Sep 281992: Sep 241993: Sep 301994: Oct 121995: Sep 291996: Oct 42000: Sep 292001: Oct 92002: Oct 92003: Oct 22004: Oct 52005: Oct 212006: Oct 82007: Oct 132008: Oct 72009: Oct 122010: Oct 102011: Oct 62012: Oct 132013: Oct 242014: Oct 202015: Oct 182016: Oct 112017: Oct 172018: Oct 182019: Oct 52020: Sep 192021: Oct 242022: Oct 32023: Oct 312024: Oct 17

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
2024Apr 27Oct 17Apr 26Oct 29
2023May 18Oct 31May 18Nov 2
2022May 9Oct 3Apr 21Oct 30
2021May 7Oct 24Apr 27Nov 3
2020May 14Sep 19Apr 23Oct 31
2019Apr 29Oct 5Apr 11Nov 2
2018Apr 24Oct 18Apr 23Oct 19
2017May 4Oct 17Apr 15Nov 8
2016May 17Oct 11Apr 28Oct 27
2015Apr 25Oct 18Apr 16Oct 18
2014May 7Oct 20Apr 20Nov 4
2013May 15Oct 24Apr 26Oct 27
2012Apr 30Oct 13Apr 30Oct 13
2011Apr 22Oct 6Apr 22Oct 28
2010May 13Oct 10Apr 14Oct 19
2009May 19Oct 12Apr 20Oct 17
2008May 2Oct 7May 1Oct 19
2007May 7Oct 13Apr 11Oct 29
2006Apr 30Oct 8Apr 29Oct 14
2005May 17Oct 21May 4Oct 30
2004May 8Oct 5Apr 12Oct 29
2003May 4Oct 2Apr 24Oct 19
2002May 20Oct 9Apr 27Oct 22
2001no dataOct 9no dataOct 9
2000May 3Sep 29Apr 14Sep 29
1998Apr 29no dataApr 27no data
1997May 11no dataApr 13no data
1996May 15Oct 4Apr 29Oct 5
1995May 7Sep 29Apr 25Nov 4
1994May 4Oct 12Apr 23Oct 12
1993Apr 28Sep 30Apr 28Sep 30
1992May 26Sep 24May 7Oct 6
1991Apr 25Sep 28Apr 14Sep 30
1990May 12Oct 17Apr 20Oct 21
1989May 9no dataApr 29no data
1988May 8Sep 29Apr 26Oct 8
1987Jun 8Sep 26May 3Oct 5
1986Jun 3Oct 7May 5Oct 11
1985May 9Oct 12May 9Oct 12
1984May 18Sep 27May 17Oct 6
1983May 19Oct 11May 18Oct 20
1982May 5Oct 11Apr 29Oct 18
1981May 19Oct 1May 18Oct 11
1980Apr 22no dataApr 22no data
1979May 7Sep 20May 7Sep 20
1978May 6Sep 26May 4Oct 16
1977May 15Oct 7May 8Oct 8
1976May 13Oct 12May 5Oct 12
1975May 9Oct 4Apr 30Oct 8
1974May 5Sep 24May 5Oct 4
1973May 7Sep 21Apr 16Oct 22
1972May 13Oct 2Apr 30Oct 11
1971May 24Oct 13Apr 28Nov 5
1970May 7Oct 17Apr 20Oct 18
1969May 27Oct 15May 2Oct 16
1968May 27Oct 6May 8Oct 31
1967May 30Oct 7May 14Oct 8
1966May 14Sep 26May 11Oct 13
1965no dataSep 28no dataSep 28
1964May 21Sep 16Apr 17Oct 6
1963May 25Sep 14May 6Sep 24
1962May 13Sep 21May 12Oct 15
1961May 31Oct 5May 31Oct 16
1960May 3Oct 2Apr 20Oct 21
1959May 18Sep 17May 9Oct 15
1958Jun 7Oct 2May 3Oct 6
1957May 19Sep 27May 17Oct 12
1956May 29Sep 21May 25Oct 11
1955May 18Sep 23Apr 12Oct 22
1954May 27Oct 7Apr 13Oct 8
1953May 4Sep 23Apr 22Oct 9
1952May 17Oct 9May 5Oct 11
1951May 19Sep 30May 14Sep 30

"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.