Last Frost Day

Frost history / Billings Wtp, MT

Billings Wtp, MT: frost dates by year

Last spring and first fall frost at NOAA station USC00240802, 1951 to 2025, measured from daily minimum temperatures.

Elevation 3,097 ft, 45.772, -108.481. Download the data (JSON) · NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 8Sep 29
EarliestApr 17 (1993)Aug 28 (1960)
LatestJun 13 (1969)Oct 26 (2022)
Trend1.1 days earlier per decade2.8 days later per decade
Years with data7174

At 28°F (hard freeze) the median last spring date is Apr 25 and the median first fall date is Oct 9.

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 2919601970198019902000201020201951: Jun 41952: May 101953: May 151954: May 41955: May 71956: May 141957: Apr 271958: Apr 291959: May 131960: May 61961: May 81962: May 11963: May 221964: May 31965: May 181966: May 191967: May 131968: May 201969: Jun 131970: Apr 301971: May 181972: May 81973: May 121974: May 161975: May 261976: May 31977: Apr 211979: May 81981: May 111983: May 151984: May 81985: May 61986: May 161987: Apr 211988: May 41989: May 11990: May 11991: May 41992: Apr 251993: Apr 171994: Apr 301995: May 141996: May 101997: May 191998: May 101999: Apr 172000: May 142001: May 202002: May 232003: May 202004: May 252005: May 132006: May 52007: Apr 202008: May 32009: May 22010: May 82011: May 52012: May 72013: May 22014: May 82015: May 112016: Apr 292017: Apr 292018: Apr 252019: May 102020: May 82021: May 222022: Apr 302024: May 42025: Apr 29

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 41952: Oct 41953: Sep 251954: Sep 301955: Sep 221956: Sep 71957: Sep 191958: Sep 251959: Sep 291960: Aug 281961: Sep 31962: Sep 41963: Oct 241964: Sep 111965: Sep 161966: Oct 101967: Oct 131968: Sep 221969: Oct 51970: Sep 121971: Sep 181972: Sep 211973: Sep 141974: Sep 211975: Oct 21976: Sep 271977: Oct 101979: Oct 11980: Oct 41981: Oct 61982: Sep 301983: Sep 191984: Sep 231985: Sep 231986: Oct 111987: Oct 71988: Oct 231989: Sep 111990: Sep 291991: Sep 181992: Sep 141993: Sep 221994: Oct 81995: Sep 211996: Sep 271997: Oct 91998: Oct 131999: Sep 282000: Sep 222001: Oct 52002: Sep 222003: Sep 182004: Oct 162005: Oct 52006: Oct 122007: Oct 152008: Sep 102009: Sep 282010: Oct 122011: Oct 192012: Oct 62013: Oct 52014: Sep 122015: Oct 162016: Oct 72017: Oct 42018: Oct 12019: Sep 302020: Oct 132021: Sep 172022: Oct 262023: Oct 142024: Oct 232025: Oct 21

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
2025Apr 29Oct 21Apr 19Oct 28
2024May 4Oct 23May 4Oct 25
2023no dataOct 14no dataOct 25
2022Apr 30Oct 26Apr 18Oct 26
2021May 22Sep 17Apr 22Nov 1
2020May 8Oct 13Apr 17Oct 16
2019May 10Sep 30Apr 13Oct 3
2018Apr 25Oct 1Apr 14Oct 14
2017Apr 29Oct 4Mar 14Oct 4
2016Apr 29Oct 7Apr 17Oct 11
2015May 11Oct 16May 11Oct 29
2014May 8Sep 12Apr 14Sep 12
2013May 2Oct 5May 2Oct 5
2012May 7Oct 6Apr 10Oct 6
2011May 5Oct 19Apr 25Oct 26
2010May 8Oct 12May 8Oct 28
2009May 2Sep 28May 2Oct 9
2008May 3Sep 10Apr 25Oct 9
2007Apr 20Oct 15Apr 13Oct 27
2006May 5Oct 12May 5Oct 18
2005May 13Oct 5May 13Oct 6
2004May 25Oct 16May 13Oct 25
2003May 20Sep 18Apr 7Oct 31
2002May 23Sep 22May 9Oct 19
2001May 20Oct 5Apr 16Oct 5
2000May 14Sep 22Apr 16Sep 22
1999Apr 17Sep 28Apr 17Oct 3
1998May 10Oct 13Mar 31Oct 20
1997May 19Oct 9Apr 13Oct 21
1996May 10Sep 27May 9Oct 21
1995May 14Sep 21May 3Sep 21
1994Apr 30Oct 8Apr 30Oct 24
1993Apr 17Sep 22Apr 15Oct 8
1992Apr 25Sep 14Apr 11Oct 7
1991May 4Sep 18Apr 21Oct 5
1990May 1Sep 29Apr 29Oct 7
1989May 1Sep 11Apr 18Sep 11
1988May 4Oct 23Apr 27Oct 26
1987Apr 21Oct 7Apr 20Oct 9
1986May 16Oct 11Apr 15Oct 11
1985May 6Sep 23Apr 25Sep 28
1984May 8Sep 23Apr 30Sep 24
1983May 15Sep 19May 14Sep 20
1982no dataSep 30no dataOct 6
1981May 11Oct 6Apr 15Oct 13
1980no dataOct 4no dataOct 10
1979May 8Oct 1May 3Oct 9
1977Apr 21Oct 10Apr 21Nov 1
1976May 3Sep 27Apr 20Oct 5
1975May 26Oct 2May 1Oct 23
1974May 16Sep 21May 16Sep 30
1973May 12Sep 14May 12Sep 15
1972May 8Sep 21May 2Sep 25
1971May 18Sep 18Apr 14Sep 18
1970Apr 30Sep 12Apr 24Oct 7
1969Jun 13Oct 5May 8Oct 11
1968May 20Sep 22May 11Oct 3
1967May 13Oct 13May 11Oct 18
1966May 19Oct 10May 12Oct 10
1965May 18Sep 16Apr 27Sep 17
1964May 3Sep 11Apr 20Sep 27
1963May 22Oct 24Apr 24Oct 26
1962May 1Sep 4Apr 29Sep 4
1961May 8Sep 3May 8Sep 24
1960May 6Aug 28Apr 30Oct 15
1959May 13Sep 29May 12Sep 29
1958Apr 29Sep 25Apr 28Sep 30
1957Apr 27Sep 19Apr 12Oct 4
1956May 14Sep 7Apr 28Oct 9
1955May 7Sep 22Apr 28Oct 23
1954May 4Sep 30May 3Oct 1
1953May 15Sep 25May 14Oct 3
1952May 10Oct 4Apr 22Oct 6
1951Jun 4Sep 4Apr 25Sep 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 1991–2020 frost probabilities.