Last Frost Day

Frost history / La Grange, WY

La Grange, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00485260, 1951 to 2009, measured from daily minimum temperatures.

Elevation 4,590 ft, 41.638, -104.167. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 19Sep 19
EarliestApr 23 (1987)Aug 30 (1964)
LatestJun 15 (1981)Oct 16 (1963)
Trend0.8 days earlier per decade2.2 days later per decade
Years with data5654

At 28°F (hard freeze) the median last spring date is May 7 and the median first fall date is Sep 29.

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 29196019701980199020001951: Jun 31952: May 111953: May 211954: Jun 31955: May 171956: May 141957: May 171958: May 31959: May 221960: May 201961: May 151962: May 161963: May 131964: Jun 21965: May 111966: May 241967: May 151968: May 191969: Jun 151970: May 161971: May 191972: May 301973: May 301974: May 211975: May 271977: May 221978: Jun 101981: Jun 151982: Jun 91983: May 201984: Jun 101985: Jun 121986: May 261987: Apr 231988: May 121989: May 61990: May 171991: May 61992: May 171993: May 111994: Apr 301995: May 231996: May 51997: May 121998: Jun 61999: May 122000: May 142001: May 252002: May 252003: May 202004: May 142005: May 282006: May 152007: Jun 82008: May 112009: Apr 30

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27196019701980199020001951: Sep 131952: Sep 21953: Sep 51954: Sep 211955: Sep 251956: Sep 231957: Sep 111958: Sep 161959: Sep 221960: Sep 241961: Sep 131962: Sep 91963: Oct 161964: Aug 301965: Sep 11966: Oct 11967: Sep 131968: Sep 41969: Oct 41970: Sep 251971: Sep 181972: Sep 151973: Sep 171974: Sep 31975: Sep 131976: Sep 91979: Sep 141980: Sep 221981: Oct 11982: Oct 61983: Sep 181984: Sep 221985: Sep 201986: Sep 271987: Sep 181988: Sep 301989: Sep 131990: Oct 21991: Sep 181992: Sep 181993: Sep 131994: Sep 211995: Sep 201996: Sep 261997: Oct 91998: Oct 21999: Sep 132000: Sep 222001: Oct 52003: Sep 182005: Sep 262006: Sep 172007: Sep 252008: Oct 7

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

"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.