Last Frost Day

Frost history / Rexburg Byu Idaho, ID

Rexburg Byu Idaho, ID: frost dates by year

Last spring and first fall frost at NOAA station USC00107644, 1977 to 2025, measured from daily minimum temperatures.

Elevation 5,005 ft, 43.808, -111.789. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 23Sep 19
EarliestApr 19 (2025)Aug 18 (1978)
LatestJul 6 (1986)Oct 14 (2022)
Trend4.4 days earlier per decade5.2 days later per decade
Years with data3636

At 28°F (hard freeze) the median last spring date is May 7 and the median first fall date is Oct 3.

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 29Jul 14198019902000201020201978: May 311979: Jun 81980: May 271981: May 131982: Jun 91983: May 171985: May 311986: Jul 61987: Jun 31988: May 201989: May 281990: Jun 11991: May 281992: May 121994: May 21996: May 232000: May 122001: Jun 142004: May 312005: Jun 102006: May 112007: May 222008: Jun 102009: May 102010: Jun 182011: May 172012: Jun 72013: May 12014: May 132015: May 122017: May 172018: May 22020: May 232021: May 102022: May 232025: Apr 19

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 27198019902000201020201977: Sep 181978: Aug 181979: Sep 141980: Sep 41981: Sep 261982: Sep 151983: Sep 101984: Sep 131986: Sep 191987: Sep 171988: Sep 111989: Aug 261990: Oct 31991: Sep 151992: Aug 241993: Aug 311995: Sep 211998: Sep 242000: Sep 232004: Sep 42005: Sep 182006: Sep 172007: Oct 12009: Sep 222010: Oct 122011: Oct 62012: Sep 132013: Sep 192014: Sep 112015: Oct 132016: Sep 262017: Sep 232020: Sep 282021: Sep 292022: Oct 142024: Oct 1

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 19no dataApr 19no data
2024no dataOct 1no dataOct 19
2022May 23Oct 14May 10Oct 24
2021May 10Sep 29May 10Sep 30
2020May 23Sep 28Apr 18Sep 28
2018May 2no dataApr 3no data
2017May 17Sep 23Apr 21Oct 13
2016no dataSep 26no dataOct 9
2015May 12Oct 13May 12Oct 29
2014May 13Sep 11May 12Sep 11
2013May 1Sep 19May 1Oct 4
2012Jun 7Sep 13May 6Oct 4
2011May 17Oct 6May 2Oct 19
2010Jun 18Oct 12May 8Oct 13
2009May 10Sep 22May 9Oct 2
2008Jun 10no dataMay 9no data
2007May 22Oct 1May 4Oct 21
2006May 11Sep 17May 3Oct 17
2005Jun 10Sep 18May 1Oct 6
2004May 31Sep 4May 15Sep 18
2001Jun 14no dataMay 21no data
2000May 12Sep 23Apr 8Sep 23
1998no dataSep 24no dataOct 5
1996May 23no dataMay 9no data
1995no dataSep 21no dataSep 21
1994May 2no dataApr 30no data
1993no dataAug 31no dataOct 10
1992May 12Aug 24Apr 24Aug 26
1991May 28Sep 15May 1Oct 4
1990Jun 1Oct 3May 16Oct 7
1989May 28Aug 26May 19Sep 12
1988May 20Sep 11May 3Sep 11
1987Jun 3Sep 17Apr 21Sep 17
1986Jul 6Sep 19Apr 28Sep 22
1985May 31no dataMay 13no data
1984no dataSep 13no dataSep 24
1983May 17Sep 10May 13Sep 20
1982Jun 9Sep 15May 31Oct 6
1981May 13Sep 26May 13Oct 1
1980May 27Sep 4Apr 17Oct 2
1979Jun 8Sep 14May 31Oct 21
1978May 31Aug 18May 25Sep 19
1977no dataSep 18no dataOct 2

"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.