Last Frost Day

Frost history / Wibaux 2 E, MT

Wibaux 2 E, MT: frost dates by year

Last spring and first fall frost at NOAA station USC00248957, 1951 to 2021, measured from daily minimum temperatures.

Elevation 2,696 ft, 46.988, -104.157. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 22Sep 13
EarliestApr 27 (1987)Aug 3 (1978)
LatestJul 4 (1972)Oct 5 (2016)
Trendlittle change (less than half a day per decade)1.9 days later per decade
Years with data7168

At 28°F (hard freeze) the median last spring date is May 14 and the median first fall date is Sep 21.

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 14Jun 29Jul 1419601970198019902000201020201951: May 261952: May 281953: May 161954: May 161955: May 41956: May 311957: May 261958: May 191959: May 231960: May 111961: May 181962: May 11963: May 231964: Jun 21965: May 281966: Jun 71967: May 141968: May 261969: Jun 141970: May 151971: May 201972: Jul 41973: May 251974: Jun 11975: May 11976: May 131977: May 61978: May 131979: Jun 81980: May 171981: May 141982: May 311983: Jun 151984: May 261985: Jun 291986: May 271987: Apr 271988: May 91989: May 261990: May 171991: May 71992: Jun 61993: May 201994: May 91995: May 251996: May 281997: May 201998: Jun 41999: May 172000: Jun 22001: May 242002: May 242003: May 202004: Jun 252005: May 152006: May 152007: May 162008: May 112009: Jun 102010: May 122011: May 152012: May 252013: May 122014: Jun 122015: May 222016: May 162017: May 302018: May 202019: May 232020: May 182021: May 27

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 1219601970198019902000201020201951: Aug 211952: Sep 221953: Sep 151954: Sep 211955: Aug 301956: Aug 191957: Sep 131958: Sep 51959: Sep 291960: Sep 91961: Sep 21962: Sep 31963: Sep 291964: Aug 111965: Aug 301966: Sep 141967: Aug 261968: Sep 221969: Sep 71970: Sep 121971: Sep 181972: Sep 11973: Sep 141974: Sep 21975: Sep 121976: Sep 91977: Oct 21978: Aug 31979: Sep 141980: Sep 91981: Sep 161982: Sep 151983: Sep 131984: Sep 151985: Aug 191986: Sep 61987: Sep 191988: Aug 281989: Sep 111990: Sep 221991: Sep 181992: Aug 251993: Sep 61994: Sep 221995: Sep 201996: Sep 111997: Sep 191998: Sep 211999: Sep 92000: Sep 222001: Oct 32002: Sep 222003: Sep 282004: Sep 72005: Sep 222006: Sep 172007: Sep 142009: Sep 222010: Sep 72011: Sep 142012: Sep 72013: Sep 202014: Sep 112015: Sep 292016: Oct 52017: Sep 52018: Sep 182020: Sep 9

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
2021May 27no dataMay 26no data
2020May 18Sep 9May 18Sep 9
2019May 23no dataMay 20no data
2018May 20Sep 18Apr 24Sep 28
2017May 30Sep 5May 19Oct 5
2016May 16Oct 5May 15Oct 7
2015May 22Sep 29May 20Oct 15
2014Jun 12Sep 11May 15Sep 12
2013May 12Sep 20May 11Oct 5
2012May 25Sep 7May 25Sep 12
2011May 15Sep 14May 15Sep 14
2010May 12Sep 7May 10Oct 14
2009Jun 10Sep 22May 23Sep 22
2008May 11no dataMay 3no data
2007May 16Sep 14May 1Sep 14
2006May 15Sep 17May 11Sep 19
2005May 15Sep 22May 15Sep 22
2004Jun 25Sep 7Jun 18Oct 1
2003May 20Sep 28May 20Sep 29
2002May 24Sep 22May 24Sep 25
2001May 24Oct 3May 4Oct 4
2000Jun 2Sep 22May 18Sep 23
1999May 17Sep 9May 8Sep 14
1998Jun 4Sep 21May 9Oct 29
1997May 20Sep 19May 20Sep 20
1996May 28Sep 11May 11Oct 2
1995May 25Sep 20May 25Sep 20
1994May 9Sep 22Apr 30Oct 23
1993May 20Sep 6May 20Sep 14
1992Jun 6Aug 25Jun 6Sep 10
1991May 7Sep 18May 6Sep 18
1990May 17Sep 22May 12Sep 29
1989May 26Sep 11May 6Sep 11
1988May 9Aug 28May 4Aug 28
1987Apr 27Sep 19Apr 27Oct 2
1986May 27Sep 6May 17Sep 7
1985Jun 29Aug 19Jun 4Sep 23
1984May 26Sep 15May 26Sep 23
1983Jun 15Sep 13Jun 6Sep 13
1982May 31Sep 15May 7Sep 15
1981May 14Sep 16May 9Sep 16
1980May 17Sep 9May 14Oct 11
1979Jun 8Sep 14Jun 8Oct 4
1978May 13Aug 3Apr 21Oct 6
1977May 6Oct 2Apr 24Oct 5
1976May 13Sep 9May 7Sep 27
1975May 1Sep 12Apr 21Sep 12
1974Jun 1Sep 2May 12Sep 2
1973May 25Sep 14May 25Sep 17
1972Jul 4Sep 1May 6Sep 21
1971May 20Sep 18May 20Sep 21
1970May 15Sep 12May 1Sep 12
1969Jun 14Sep 7May 11Sep 27
1968May 26Sep 22May 20Oct 3
1967May 14Aug 26May 13Sep 27
1966Jun 7Sep 14May 9Sep 14
1965May 28Aug 30May 27Sep 5
1964Jun 2Aug 11May 31Sep 11
1963May 23Sep 29May 22Oct 26
1962May 1Sep 3Apr 17Oct 23
1961May 18Sep 2May 2Sep 14
1960May 11Sep 9May 11Sep 11
1959May 23Sep 29May 23Sep 30
1958May 19Sep 5May 19Sep 25
1957May 26Sep 13May 23Sep 13
1956May 31Aug 19May 14Sep 4
1955May 4Aug 30Apr 20Sep 10
1954May 16Sep 21May 7Sep 21
1953May 16Sep 15May 14Sep 21
1952May 28Sep 22May 28Sep 22
1951May 26Aug 21May 10Sep 23

"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.