Last Frost Day

Frost history / Wamsutter, WY

Wamsutter, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00489459, 1951 to 2025, measured from daily minimum temperatures.

Elevation 6,740 ft, 41.672, -107.978. Download the data (JSON) · NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 9Sep 11
EarliestMay 9 (2023)Aug 2 (2025)
LatestJul 2 (1997)Oct 14 (1963)
Trend0.8 days earlier per decadelittle change (less than half a day per decade)
Years with data6056

At 28°F (hard freeze) the median last spring date is May 24 and the median first fall date is Sep 18.

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 1419601970198019902000201020201951: Jun 301952: Jun 161953: Jun 251954: Jun 81955: Jun 91956: May 151957: Jun 161958: May 151959: Jun 11960: Jun 211961: May 171962: Jun 81963: May 181964: Jun 21965: May 281966: Jun 131967: Jun 71968: Jun 301969: Jun 141970: Jun 31974: Jun 81975: Jun 201976: Jun 141977: May 301978: Jun 201979: Jun 91980: Jun 71981: Jun 161982: Jun 191983: Jun 141984: Jun 121988: Jun 11989: Jun 221990: Jun 21991: May 131992: Jun 161994: Jun 101995: May 231996: Jun 21997: Jul 21998: Jun 81999: May 182000: Jun 172001: Jun 142009: May 172010: Jun 122011: Jun 102013: Jun 42014: Jun 242015: May 172016: May 272017: Jun 132018: May 202019: Jun 102020: May 252021: May 282022: Jun 52023: May 92024: Jun 182025: Jun 23

First fall frost (32°F)

Jul 14Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201951: Sep 91952: Sep 141953: Sep 41954: Sep 291955: Sep 111956: Aug 311957: Sep 111958: Sep 161959: Sep 31960: Sep 231961: Sep 31962: Aug 311963: Oct 141964: Aug 291965: Aug 301966: Aug 211967: Sep 131968: Sep 41969: Sep 161974: Sep 31975: Aug 251976: Aug 271977: Sep 91978: Aug 151979: Sep 131980: Sep 221981: Sep 171982: Sep 121983: Sep 201988: Sep 121989: Sep 41990: Sep 211991: Sep 151992: Aug 251993: Sep 131994: Sep 221996: Aug 71997: Sep 231998: Sep 281999: Sep 92008: Sep 22010: Aug 242011: Sep 212013: Sep 202014: Sep 122015: Sep 82016: Sep 102017: Sep 172018: Sep 252019: Sep 182020: Sep 82021: Sep 202022: Sep 112023: Sep 162024: Sep 132025: Aug 2

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 23Aug 2May 22Oct 7
2024Jun 18Sep 13May 24Oct 1
2023May 9Sep 16Apr 28Oct 5
2022Jun 5Sep 11May 25Oct 9
2021May 28Sep 20May 27Sep 21
2020May 25Sep 8May 24Sep 8
2019Jun 10Sep 18Jun 10Oct 3
2018May 20Sep 25May 1Sep 25
2017Jun 13Sep 17May 23Sep 17
2016May 27Sep 10May 11Sep 10
2015May 17Sep 8May 10Oct 15
2014Jun 24Sep 12Jun 24Sep 12
2013Jun 4Sep 20May 3Sep 20
2011Jun 10Sep 21Jun 10Sep 21
2010Jun 12Aug 24May 23Sep 7
2009May 17no dataMay 9no data
2008no dataSep 2no dataOct 11
2001Jun 14no dataJun 14no data
2000Jun 17no dataJun 1no data
1999May 18Sep 9May 18Sep 11
1998Jun 8Sep 28May 27Oct 6
1997Jul 2Sep 23May 19Oct 9
1996Jun 2Aug 7May 22Sep 23
1995May 23no dataMay 14no data
1994Jun 10Sep 22Jun 10Sep 22
1993no dataSep 13no dataSep 14
1992Jun 16Aug 25Apr 26Sep 17
1991May 13Sep 15May 6Sep 15
1990Jun 2Sep 21May 16Sep 22
1989Jun 22Sep 4Jun 22Sep 11
1988Jun 1Sep 12May 8Sep 18
1984Jun 12no dataJun 9no data
1983Jun 14Sep 20May 31Sep 20
1982Jun 19Sep 12Jun 19Sep 14
1981Jun 16Sep 17May 13Sep 26
1980Jun 7Sep 22May 27Sep 22
1979Jun 9Sep 13Jun 2Sep 14
1978Jun 20Aug 15Jun 1Sep 14
1977May 30Sep 9May 21Sep 9
1976Jun 14Aug 27Jun 14Aug 27
1975Jun 20Aug 25Jun 16Sep 18
1974Jun 8Sep 3May 31Sep 3
1970Jun 3no dataJun 2no data
1969Jun 14Sep 16Jun 1Oct 3
1968Jun 30Sep 4May 25Sep 17
1967Jun 7Sep 13May 14Sep 13
1966Jun 13Aug 21May 24Oct 1
1965May 28Aug 30May 28Sep 16
1964Jun 2Aug 29Jun 2Sep 11
1963May 18Oct 14May 13Oct 17
1962Jun 8Aug 31May 16Aug 31
1961May 17Sep 3May 17Sep 14
1960Jun 21Sep 23May 20Oct 12
1959Jun 1Sep 3May 21Sep 22
1958May 15Sep 16May 1Sep 25
1957Jun 16Sep 11May 4Sep 11
1956May 15Aug 31May 14Aug 31
1955Jun 9Sep 11Jun 9Sep 23
1954Jun 8Sep 29Jun 3Sep 30
1953Jun 25Sep 4Jun 25Sep 4
1952Jun 16Sep 14May 27Sep 14
1951Jun 30Sep 9Jun 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 1991–2020 frost probabilities.