Last Frost Day

Frost history / Alpine, UT

Alpine, UT: frost dates by year

Last spring and first fall frost at NOAA station USC00420061, 1975 to 2025, measured from daily minimum temperatures.

Elevation 5,100 ft, 40.464, -111.771. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 8Oct 5
EarliestApr 15 (2001)Sep 14 (1993)
LatestJun 17 (1998)Nov 5 (2015)
Trend6.9 days earlier per decade4.7 days later per decade
Years with data4346

At 28°F (hard freeze) the median last spring date is Apr 21 and the median first fall date is Oct 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)

Mar 31Apr 15Apr 30May 15May 30Jun 14Jun 29198019902000201020201975: May 271976: Jun 151977: May 211978: May 311979: Jun 81980: May 241981: May 161982: Jun 91984: May 81985: May 291986: May 221987: May 31988: May 61989: May 191994: May 21995: May 141996: May 61997: May 21998: Jun 171999: May 172000: May 122001: Apr 152002: Jun 102003: May 192004: Apr 292005: May 112006: Apr 202009: Apr 272011: May 52012: May 62013: May 22014: May 132015: Apr 172016: Apr 152017: May 182018: Apr 302019: May 22020: Apr 172021: Apr 202022: May 102023: Apr 262024: May 82025: Apr 19

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11198019902000201020201975: Sep 191976: Oct 51977: Sep 231978: Sep 171979: Oct 211980: Sep 221981: Oct 141982: Sep 281983: Sep 201984: Sep 251985: Sep 231986: Sep 261987: Oct 161988: Sep 191989: Oct 51993: Sep 141994: Oct 31995: Oct 51996: Sep 181997: Oct 121998: Oct 51999: Sep 282000: Sep 242001: Oct 102002: Oct 122004: Oct 292005: Oct 52007: Sep 252008: Oct 112009: Oct 12010: Oct 232011: Oct 62012: Oct 62013: Sep 282014: Oct 282015: Nov 52016: Oct 62017: Oct 22018: Oct 122019: Sep 302020: Oct 162021: Oct 132022: Oct 232023: Oct 272024: Oct 302025: Oct 16

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
2025Apr 19Oct 16Apr 19Oct 28
2024May 8Oct 30Apr 18Nov 4
2023Apr 26Oct 27Apr 20Oct 27
2022May 10Oct 23Apr 13Oct 27
2021Apr 20Oct 13Apr 20Oct 15
2020Apr 17Oct 16Apr 17Oct 23
2019May 2Sep 30Mar 31Oct 10
2018Apr 30Oct 12Apr 18Oct 15
2017May 18Oct 2May 18Oct 15
2016Apr 15Oct 6Mar 19Nov 17
2015Apr 17Nov 5Apr 16Nov 6
2014May 13Oct 28Apr 29Nov 4
2013May 2Sep 28May 2Oct 5
2012May 6Oct 6Apr 28Oct 26
2011May 5Oct 6May 1Oct 27
2010no dataOct 23no dataOct 28
2009Apr 27Oct 1Apr 6Oct 2
2008no dataOct 11no dataOct 12
2007no dataSep 25no dataOct 22
2006Apr 20no dataApr 19no data
2005May 11Oct 5Apr 15Oct 31
2004Apr 29Oct 29Mar 7Nov 1
2003May 19no dataApr 8no data
2002Jun 10Oct 12May 9Oct 29
2001Apr 15Oct 10Apr 13Oct 10
2000May 12Sep 24Apr 1Nov 2
1999May 17Sep 28May 11Oct 17
1998Jun 17Oct 5Apr 18Nov 4
1997May 2Oct 12May 2Oct 13
1996May 6Sep 18Apr 29Oct 17
1995May 14Oct 5Apr 16Oct 13
1994May 2Oct 3Apr 30Oct 30
1993no dataSep 14no dataOct 30
1989May 19Oct 5Apr 29Oct 17
1988May 6Sep 19May 3Nov 12
1987May 3Oct 16Apr 21Oct 20
1986May 22Sep 26Apr 27Sep 29
1985May 29Sep 23Apr 24Sep 29
1984May 8Sep 25May 7Sep 25
1983no dataSep 20no dataSep 20
1982Jun 9Sep 28May 28Oct 6
1981May 16Oct 14May 7Oct 22
1980May 24Sep 22Apr 14Oct 23
1979Jun 8Oct 21May 9Oct 21
1978May 31Sep 17May 5Sep 18
1977May 21Sep 23Apr 21Oct 11
1976Jun 15Oct 5Apr 27Oct 18
1975May 27Sep 19May 26Oct 9

"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.