Last Frost Day

Frost history / Stevensville, MT

Stevensville, MT: frost dates by year

Last spring and first fall frost at NOAA station USC00247894, 1951 to 2025, measured from daily minimum temperatures.

Elevation 3,375 ft, 46.514, -114.091. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 29Sep 11
EarliestApr 19 (2016)Aug 12 (1985)
LatestJul 19 (1999)Oct 19 (2023)
Trend2.6 days earlier per decade2.7 days later per decade
Years with data6672

At 28°F (hard freeze) the median last spring date is May 14 and the median first fall date is Sep 23.

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 14Jun 29Jul 14Jul 2919601970198019902000201020201951: Jun 31952: Jun 131953: Jun 261954: Jun 181955: May 281957: Apr 271958: May 41959: May 291960: Jun 181961: May 281962: Jun 61963: May 201964: May 261965: Jun 281966: Jun 131967: May 271968: May 311969: Jun 131970: May 311971: Jul 71972: May 261973: Jun 111974: Jun 11976: May 291977: May 301978: May 301980: May 121981: May 121982: Jun 11983: Jul 31984: Jun 21985: May 171986: May 241987: Jun 31988: May 201989: May 301990: May 261991: Jun 181992: May 181996: May 301997: May 211998: May 281999: Jul 192000: Jun 112001: Jun 52002: May 172003: May 202004: May 142005: May 252006: May 302007: May 232008: May 102009: May 222010: May 212011: May 312012: Jun 72013: May 22014: May 142016: Apr 192017: Jun 112020: May 82021: May 292022: May 112023: Apr 282024: May 302025: May 18

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201951: Sep 41952: Sep 141953: Sep 41954: Sep 61955: Sep 181956: Sep 31957: Sep 101958: Sep 31959: Sep 21960: Aug 281961: Sep 71962: Sep 41963: Sep 151964: Sep 41965: Aug 301966: Sep 301967: Sep 141968: Sep 241969: Aug 301970: Sep 91971: Sep 121972: Sep 71973: Sep 21974: Sep 21976: Aug 271977: Aug 311978: Sep 171979: Sep 111980: Aug 191981: Sep 201982: Sep 111983: Sep 51984: Sep 131985: Aug 121986: Sep 221987: Sep 51988: Sep 121989: Sep 61990: Oct 61991: Sep 221992: Aug 251993: Aug 251994: Sep 71995: Sep 211997: Sep 191998: Sep 211999: Sep 12000: Sep 72001: Sep 202002: Sep 212003: Sep 142004: Oct 22005: Sep 112006: Sep 182007: Sep 102008: Sep 112009: Sep 232010: Sep 62011: Sep 212012: Sep 122013: Sep 272014: Sep 122015: Sep 282016: Sep 132017: Sep 232019: Sep 282020: Sep 82021: Sep 172022: Oct 92023: Oct 192024: Oct 32025: Sep 26

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 18Sep 26May 1Oct 5
2024May 30Oct 3Apr 23Oct 3
2023Apr 28Oct 19Apr 23Oct 25
2022May 11Oct 9May 11Oct 17
2021May 29Sep 17Apr 27Oct 12
2020May 8Sep 8May 8Oct 22
2019no dataSep 28no dataSep 29
2017Jun 11Sep 23May 8Oct 4
2016Apr 19Sep 13Apr 19Oct 12
2015no dataSep 28no dataOct 12
2014May 14Sep 12May 12Sep 12
2013May 2Sep 27May 2Sep 27
2012Jun 7Sep 12May 12Oct 4
2011May 31Sep 21May 2Oct 9
2010May 21Sep 6May 13Oct 12
2009May 22Sep 23May 21Oct 6
2008May 10Sep 11May 10Oct 9
2007May 23Sep 10May 6Sep 30
2006May 30Sep 18May 10Oct 8
2005May 25Sep 11May 2Oct 6
2004May 14Oct 2Apr 30Oct 10
2003May 20Sep 14May 20Sep 18
2002May 17Sep 21May 11Sep 22
2001Jun 5Sep 20May 31Oct 5
2000Jun 11Sep 7Apr 30Sep 23
1999Jul 19Sep 1May 11Sep 8
1998May 28Sep 21Apr 21Oct 3
1997May 21Sep 19May 8Oct 8
1996May 30no dataMay 6no data
1995no dataSep 21no dataSep 21
1994no dataSep 7no dataSep 22
1993no dataAug 25no dataSep 21
1992May 18Aug 25May 12Aug 25
1991Jun 18Sep 22May 26Sep 22
1990May 26Oct 6May 19Oct 7
1989May 30Sep 6May 20Sep 11
1988May 20Sep 12May 18Sep 22
1987Jun 3Sep 5May 22Sep 5
1986May 24Sep 22May 23Sep 23
1985May 17Aug 12May 17Sep 20
1984Jun 2Sep 13May 22Sep 14
1983Jul 3Sep 5May 14Sep 10
1982Jun 1Sep 11May 30Sep 11
1981May 12Sep 20May 9Sep 23
1980May 12Aug 19Apr 17Sep 25
1979no dataSep 11no dataOct 3
1978May 30Sep 17May 29Sep 17
1977May 30Aug 31May 30Oct 2
1976May 29Aug 27May 26Sep 9
1974Jun 1Sep 2May 19Sep 13
1973Jun 11Sep 2May 27Sep 17
1972May 26Sep 7May 4Sep 26
1971Jul 7Sep 12May 19Sep 15
1970May 31Sep 9May 14Sep 14
1969Jun 13Aug 30May 8Sep 15
1968May 31Sep 24May 31Oct 2
1967May 27Sep 14May 26Oct 15
1966Jun 13Sep 30May 19Sep 30
1965Jun 28Aug 30May 19Sep 17
1964May 26Sep 4May 26Sep 10
1963May 20Sep 15May 20Oct 20
1962Jun 6Sep 4May 14Sep 4
1961May 28Sep 7May 12Sep 12
1960Jun 18Aug 28May 23Aug 28
1959May 29Sep 2May 12Sep 9
1958May 4Sep 3Apr 30Sep 28
1957Apr 27Sep 10Apr 18Oct 5
1956no dataSep 3no dataSep 23
1955May 28Sep 18May 28Sep 23
1954Jun 18Sep 6Jun 17Oct 1
1953Jun 26Sep 4May 23Sep 21
1952Jun 13Sep 14Jun 13Sep 14
1951Jun 3Sep 4May 29Sep 21

"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.