Last Frost Day

Frost history / Mora, MN

Mora, MN: frost dates by year

Last spring and first fall frost at NOAA station USC00215615, 1951 to 2025, measured from daily minimum temperatures.

Elevation 1,018 ft, 45.877, -93.315. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 13Sep 21
EarliestApr 20 (1964)Aug 10 (1982)
LatestJun 4 (1990)Oct 18 (2021)
Trend0.7 days earlier per decade2.1 days later per decade
Years with data6670

At 28°F (hard freeze) the median last spring date is May 2 and the median first fall date is Oct 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)

Apr 15Apr 30May 15May 30Jun 1419601970198019902000201020201951: May 111952: Apr 241953: May 161954: May 201955: Apr 221956: May 161957: May 161958: May 91959: May 151960: May 121961: May 261962: Apr 231963: May 231964: Apr 201965: May 291966: May 101967: May 201968: May 51969: May 121970: May 171971: May 271972: May 101973: May 171974: May 251975: May 161976: May 181977: May 71978: May 101979: Jun 11981: May 191982: May 71983: May 251984: May 291985: Jun 41986: Jun 11989: May 261990: Jun 41991: May 61993: May 161994: May 101995: May 61996: May 131997: May 211999: Apr 292000: May 272003: May 32004: May 152005: May 132006: May 222009: Apr 292010: May 92011: May 42012: Apr 272013: May 132014: May 42015: May 202016: May 162017: Apr 292018: Apr 282019: May 102020: May 132021: May 302022: May 42023: May 42024: Apr 242025: May 4

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201951: Sep 241952: Sep 241953: Sep 221954: Sep 221955: Sep 111956: Sep 241957: Sep 261958: Oct 11959: Sep 171960: Sep 301961: Sep 231962: Sep 201963: Sep 131964: Sep 151965: Sep 261966: Sep 261967: Sep 241968: Oct 41969: Sep 91970: Sep 131971: Sep 161972: Sep 221973: Sep 181974: Sep 11975: Sep 121976: Sep 101977: Oct 21978: Sep 211979: Sep 191981: Sep 171982: Aug 101983: Sep 131984: Aug 301985: Sep 201986: Aug 261987: Aug 221988: Sep 51989: Sep 121990: Oct 71991: Sep 201993: Sep 181994: Oct 101995: Sep 201997: Sep 211999: Sep 212000: Sep 212001: Sep 242002: Sep 242003: Sep 292004: Sep 292006: Sep 212007: Sep 122008: Oct 32009: Sep 302010: Oct 32011: Sep 152012: Sep 182013: Oct 172014: Sep 132015: Oct 162016: Oct 82017: Oct 102018: Sep 292019: Oct 122020: Sep 182021: Oct 182022: Sep 282023: Oct 92024: Oct 42025: Oct 8

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 4Oct 8Apr 20Oct 8
2024Apr 24Oct 4Apr 6Oct 14
2023May 4Oct 9Apr 27Oct 28
2022May 4Sep 28Apr 28Oct 18
2021May 30Oct 18May 11Oct 22
2020May 13Sep 18May 13Oct 4
2019May 10Oct 12May 3Oct 25
2018Apr 28Sep 29Apr 25Oct 12
2017Apr 29Oct 10Apr 28Oct 10
2016May 16Oct 8Apr 13Nov 9
2015May 20Oct 16Apr 27Oct 18
2014May 4Sep 13Apr 19Oct 9
2013May 13Oct 17May 3Oct 20
2012Apr 27Sep 18Apr 20Sep 23
2011May 4Sep 15May 3Sep 15
2010May 9Oct 3May 9Oct 22
2009Apr 29Sep 30Apr 15Oct 9
2008no dataOct 3no dataOct 21
2007no dataSep 12no dataSep 15
2006May 22Sep 21Apr 25Oct 10
2005May 13no dataMay 4no data
2004May 15Sep 29May 15Oct 5
2003May 3Sep 29May 2Oct 1
2002no dataSep 24no dataOct 7
2001no dataSep 24no dataSep 25
2000May 27Sep 21May 27Sep 24
1999Apr 29Sep 21Apr 24Sep 21
1997May 21Sep 21May 13Oct 15
1996May 13no dataApr 30no data
1995May 6Sep 20Apr 27Sep 22
1994May 10Oct 10Apr 29Oct 10
1993May 16Sep 18Apr 26Oct 2
1991May 6Sep 20Apr 24Sep 20
1990Jun 4Oct 7May 11Oct 9
1989May 26Sep 12May 7Sep 22
1988no dataSep 5no dataOct 2
1987no dataAug 22no dataAug 23
1986Jun 1Aug 26May 20Sep 15
1985Jun 4Sep 20Apr 10Sep 20
1984May 29Aug 30May 29Sep 4
1983May 25Sep 13May 25Sep 22
1982May 7Aug 10Apr 28Sep 20
1981May 19Sep 17May 19Sep 18
1979Jun 1Sep 19May 21Oct 7
1978May 10Sep 21May 2Sep 22
1977May 7Oct 2May 2Oct 3
1976May 18Sep 10May 8Sep 23
1975May 16Sep 12Apr 21Oct 2
1974May 25Sep 1May 6Sep 3
1973May 17Sep 18May 17Sep 20
1972May 10Sep 22Apr 26Sep 30
1971May 27Sep 16May 12Sep 19
1970May 17Sep 13May 6Sep 28
1969May 12Sep 9Apr 28Sep 28
1968May 5Oct 4May 5Oct 4
1967May 20Sep 24May 6Sep 28
1966May 10Sep 26May 10Oct 16
1965May 29Sep 26Apr 28Sep 26
1964Apr 20Sep 15Apr 18Oct 9
1963May 23Sep 13Apr 24Oct 29
1962Apr 23Sep 20Apr 17Oct 24
1961May 26Sep 23May 2Sep 28
1960May 12Sep 30May 1Oct 18
1959May 15Sep 17May 15Oct 17
1958May 9Oct 1May 1Oct 5
1957May 16Sep 26May 5Oct 11
1956May 16Sep 24May 1Oct 9
1955Apr 22Sep 11Apr 7Oct 15
1954May 20Sep 22May 6Oct 18
1953May 16Sep 22May 13Oct 7
1952Apr 24Sep 24Apr 15Oct 5
1951May 11Sep 24Apr 22Oct 8

"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.