Last Frost Day

Frost history / Virginia City, MT

Virginia City, MT: frost dates by year

Last spring and first fall frost at NOAA station USC00248597, 1951 to 2025, measured from daily minimum temperatures.

Elevation 5,773 ft, 45.292, -111.948. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 16Sep 9
EarliestMay 9 (2023)Aug 4 (1980)
LatestJul 18 (1993)Oct 24 (1963)
Trend1.0 days earlier per decade1.6 days later per decade
Years with data7066

At 28°F (hard freeze) the median last spring date is May 22 and the median first fall date is Sep 20.

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 30May 15May 30Jun 14Jun 29Jul 14Jul 2919601970198019902000201020201951: Jun 81952: May 301953: Jun 241954: Jun 181955: Jul 21956: Jun 221957: Jun 141958: May 121959: Jul 81960: Jun 221961: May 221962: Jun 71963: Jul 111964: Jun 111965: Jun 291966: Jun 251967: May 131968: Jun 141969: Jun 271970: May 241971: Jun 21972: May 271973: Jun 191974: Jun 71975: Jun 281976: Jun 271977: Jul 71978: Jun 201979: Jun 91980: Jun 281981: Jul 81982: Jun 91983: Jun 201984: Jun 91985: Jun 261986: May 241987: Jun 31988: Jun 301989: Jun 211990: Jun 131991: Jun 151992: May 161993: Jul 181994: Jun 171995: Jun 201996: Jun 191997: Jun 241998: Jun 211999: Jul 52000: May 302001: Jun 142002: May 252003: Jun 232004: May 302005: Jun 92006: May 312007: Jun 62008: Jun 132009: Jun 232010: Jun 182011: Jun 102012: Jun 202013: Jun 152014: May 192015: May 112017: Jun 132022: Jun 202023: May 92024: Jun 172025: Jun 22

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 121952: Sep 141954: Sep 191955: Sep 191956: Aug 311957: Sep 91958: Sep 201959: Sep 21960: Aug 281961: Sep 21962: Aug 231963: Oct 241964: Aug 271965: Aug 301966: Sep 291967: Sep 131968: Sep 171969: Sep 41970: Sep 91971: Sep 141972: Sep 71973: Sep 31974: Sep 21975: Aug 291976: Aug 271977: Aug 271978: Aug 171979: Sep 111980: Aug 41981: Aug 311982: Sep 111983: Sep 101984: Sep 81985: Aug 91986: Sep 161987: Sep 171988: Sep 101989: Sep 101990: Oct 61991: Sep 151992: Aug 241993: Aug 301994: Oct 31995: Sep 201996: Sep 61997: Sep 281998: Oct 31999: Sep 72000: Sep 202001: Sep 82002: Sep 192003: Sep 92004: Sep 42005: Aug 312006: Aug 312007: Sep 102008: Sep 22009: Sep 82010: Sep 62011: Oct 92012: Sep 122014: Sep 112021: Sep 202023: Oct 12024: Sep 292025: Oct 5

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
2025Jun 22Oct 5Apr 21Oct 5
2024Jun 17Sep 29May 22Oct 17
2023May 9Oct 1May 8Oct 1
2022Jun 20no dataMay 23no data
2021no dataSep 20no dataSep 21
2017Jun 13no dataMay 19no data
2015May 11no dataMay 11no data
2014May 19Sep 11May 13Sep 12
2013Jun 15no dataMay 2no data
2012Jun 20Sep 12Jun 19Oct 4
2011Jun 10Oct 9May 18Oct 9
2010Jun 18Sep 6Jun 18Sep 6
2009Jun 23Sep 8May 13Oct 1
2008Jun 13Sep 2Jun 11Sep 23
2007Jun 6Sep 10May 6Sep 30
2006May 31Aug 31May 16Aug 31
2005Jun 9Aug 31May 25Sep 28
2004May 30Sep 4May 30Oct 11
2003Jun 23Sep 9May 20Sep 13
2002May 25Sep 19May 23Sep 21
2001Jun 14Sep 8May 21Sep 8
2000May 30Sep 20May 12Sep 20
1999Jul 5Sep 7Jun 9Sep 27
1998Jun 21Oct 3May 28Oct 5
1997Jun 24Sep 28May 19Oct 5
1996Jun 19Sep 6Jun 19Sep 6
1995Jun 20Sep 20Jun 7Sep 21
1994Jun 17Oct 3Jun 15Oct 3
1993Jul 18Aug 30Jun 13Sep 13
1992May 16Aug 24May 10Aug 25
1991Jun 15Sep 15May 12Sep 22
1990Jun 13Oct 6May 16Oct 6
1989Jun 21Sep 10May 26Sep 11
1988Jun 30Sep 10May 20Sep 12
1987Jun 3Sep 17Jun 2Sep 17
1986May 24Sep 16May 23Sep 27
1985Jun 26Aug 9May 13Sep 20
1984Jun 9Sep 8Jun 2Sep 22
1983Jun 20Sep 10May 17Sep 10
1982Jun 9Sep 11May 31Sep 11
1981Jul 8Aug 31Jul 8Sep 21
1980Jun 28Aug 4May 27Sep 22
1979Jun 9Sep 11Jun 8Oct 3
1978Jun 20Aug 17May 30Sep 16
1977Jul 7Aug 27May 20Sep 18
1976Jun 27Aug 27Jun 27Aug 27
1975Jun 28Aug 29Jun 28Sep 19
1974Jun 7Sep 2May 31Sep 2
1973Jun 19Sep 3Jun 19Sep 15
1972May 27Sep 7May 4Sep 7
1971Jun 2Sep 14May 19Sep 18
1970May 24Sep 9May 14Sep 12
1969Jun 27Sep 4May 1Oct 3
1968Jun 14Sep 17May 9Oct 2
1967May 13Sep 13May 13Oct 4
1966Jun 25Sep 29Jun 4Sep 29
1965Jun 29Aug 30May 18Aug 30
1964Jun 11Aug 27May 3Sep 19
1963Jul 11Oct 24Jun 30Oct 24
1962Jun 7Aug 23Jun 7Sep 8
1961May 22Sep 2May 7Sep 14
1960Jun 22Aug 28May 28Aug 28
1959Jul 8Sep 2May 12Sep 9
1958May 12Sep 20May 2Sep 20
1957Jun 14Sep 9Jun 14Sep 19
1956Jun 22Aug 31May 13Sep 22
1955Jul 2Sep 19Jul 2Sep 30
1954Jun 18Sep 19May 28Sep 29
1953Jun 24no dataMay 23no data
1952May 30Sep 14Apr 22Sep 14
1951Jun 8Sep 12Jun 3Sep 12

"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.