Last Frost Day

Frost history / Muddy Gap, WY

Muddy Gap, WY: frost dates by year

Last spring and first fall frost at NOAA station USC00486595, 1951 to 2003, measured from daily minimum temperatures.

Elevation 6,248 ft, 42.363, -107.444. Download the data (JSON) · NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 29Sep 17
EarliestMay 5 (1958)Aug 22 (1966)
LatestJul 4 (1972)Oct 23 (1990)
Trend0.5 days later per decade1.0 days later per decade
Years with data4044

At 28°F (hard freeze) the median last spring date is May 13 and the median first fall date is Sep 27.

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 14196019701980199020001951: Jun 41952: May 191953: Jun 251954: Jun 31955: May 281956: May 151957: May 161958: May 51959: May 211960: May 251961: May 171962: Jun 81963: May 221964: May 301965: May 271966: May 231968: May 201969: Jun 131970: Jun 11971: May 241972: Jul 41973: Jun 181974: Jun 81975: May 281981: Jun 161982: Jun 91983: May 201984: Jun 101985: Jun 261987: Jun 51989: Jun 221990: Jun 21991: May 51992: May 51993: Jun 41999: May 122000: Jun 12001: Jun 132002: May 242003: May 21

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11196019701980199020001951: Sep 121952: Sep 151953: Sep 201954: Sep 211955: Sep 301956: Sep 61957: Sep 111958: Sep 251959: Sep 281960: Sep 171961: Sep 141962: Sep 81963: Oct 161964: Sep 111965: Sep 161966: Aug 221967: Oct 71968: Sep 171969: Oct 31970: Sep 101971: Sep 161972: Sep 51974: Sep 121975: Sep 111980: Sep 221982: Sep 141983: Sep 181984: Sep 151985: Sep 201986: Sep 261987: Sep 181989: Sep 111990: Oct 231991: Sep 151992: Aug 261993: Sep 131996: Sep 231997: Oct 61998: Oct 41999: Sep 132000: Sep 202001: Oct 42002: Sep 222003: Sep 13

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
2003May 21Sep 13May 21Oct 5
2002May 24Sep 22May 10Sep 22
2001Jun 13Oct 4May 21Oct 5
2000Jun 1Sep 20May 13Sep 22
1999May 12Sep 13May 11Oct 16
1998no dataOct 4no dataOct 12
1997no dataOct 6no dataOct 12
1996no dataSep 23no dataSep 23
1993Jun 4Sep 13May 9Sep 14
1992May 5Aug 26Apr 26Sep 18
1991May 5Sep 15May 5Sep 18
1990Jun 2Oct 23May 16Oct 24
1989Jun 22Sep 11May 29Sep 11
1987Jun 5Sep 18May 4Sep 28
1986no dataSep 26no dataSep 29
1985Jun 26Sep 20Apr 29Sep 20
1984Jun 10Sep 15May 8Sep 24
1983May 20Sep 18May 15Sep 19
1982Jun 9Sep 14May 31Oct 9
1981Jun 16no dataMay 13no data
1980no dataSep 22no dataSep 22
1975May 28Sep 11May 21Sep 20
1974Jun 8Sep 12May 14Sep 12
1973Jun 18no dataMay 14no data
1972Jul 4Sep 5May 3Sep 26
1971May 24Sep 16May 19Sep 17
1970Jun 1Sep 10May 1Sep 12
1969Jun 13Oct 3Jun 13Oct 3
1968May 20Sep 17May 20Oct 8
1967no dataOct 7no dataOct 15
1966May 23Aug 22May 23Oct 3
1965May 27Sep 16May 11Sep 16
1964May 30Sep 11May 3Sep 27
1963May 22Oct 16May 21Oct 27
1962Jun 8Sep 8Apr 30Sep 8
1961May 17Sep 14May 8Sep 14
1960May 25Sep 17May 15Oct 17
1959May 21Sep 28May 10Sep 29
1958May 5Sep 25May 1Sep 28
1957May 16Sep 11Apr 28Sep 11
1956May 15Sep 6May 13Sep 6
1955May 28Sep 30May 17Sep 30
1954Jun 3Sep 21Jun 3Oct 1
1953Jun 25Sep 20May 13Oct 3
1952May 19Sep 15May 18Oct 6
1951Jun 4Sep 12Jun 4Sep 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 1991–2020 frost probabilities.