Last Frost Day

Frost history / Fairfield Rs, ID

Fairfield Rs, ID: frost dates by year

Last spring and first fall frost at NOAA station USC00103108, 1952 to 2025, measured from daily minimum temperatures.

Elevation 5,065 ft, 43.343, -114.790. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianJun 24Sep 3
EarliestMay 1 (2015)Aug 2 (1957)
LatestJul 23 (1954)Oct 10 (1963)
Trend3.1 days earlier per decade2.7 days later per decade
Years with data5252

At 28°F (hard freeze) the median last spring date is May 28 and the median first fall date is Sep 15.

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 29Jul 14Jul 2919601970198019902000201020201952: Jun 161953: Jun 251954: Jul 231955: Jul 81956: Jun 301957: Jun 151958: Jul 31959: Jul 81960: Jun 211961: May 191962: Jun 71963: Jun 301964: Jun 201965: Jun 281966: Jul 31967: Jun 51968: Jul 11969: Jun 301970: Jun 301971: Jun 291972: Jun 191973: Jul 21975: Jun 281976: Jun 271977: May 301978: Jun 261979: Jun 201980: Jun 271981: Jul 81982: May 311983: Jul 161984: Jul 91985: Jun 261986: Jul 181987: Jun 21988: Jun 111992: Jul 141993: Jul 71994: Jul 51996: Jun 192004: May 302009: Jun 232010: Jun 172011: Jun 172012: Jun 82015: May 12016: May 222017: Jun 102018: May 22019: Jun 212024: Jun 192025: Jun 22

First fall frost (32°F)

Jul 14Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201952: Sep 11953: Aug 251954: Aug 181955: Sep 171956: Aug 31957: Aug 21958: Aug 301959: Aug 211960: Aug 231961: Sep 31962: Sep 91963: Oct 101964: Aug 271965: Aug 291966: Aug 211967: Sep 121968: Aug 231969: Sep 41970: Sep 91971: Sep 151972: Sep 71973: Sep 21975: Aug 251976: Aug 271977: Aug 311978: Aug 171979: Sep 121980: Sep 41981: Sep 31982: Sep 111983: Sep 51984: Aug 201985: Aug 91986: Sep 101987: Sep 51988: Sep 111989: Aug 261991: Aug 21993: Aug 171995: Aug 92008: Sep 12009: Sep 92010: Aug 232011: Oct 92013: Sep 182015: Sep 52016: Sep 52017: Sep 152019: Sep 282023: Sep 192024: Sep 122025: Oct 5

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 22Oct 5Apr 22Oct 18
2024Jun 19Sep 12Jun 17Sep 30
2023no dataSep 19no dataSep 22
2019Jun 21Sep 28May 2Sep 29
2018May 2no dataMay 1no data
2017Jun 10Sep 15May 13Sep 22
2016May 22Sep 5Apr 29Oct 6
2015May 1Sep 5Apr 30Sep 5
2013no dataSep 18no dataOct 4
2012Jun 8no dataJun 6no data
2011Jun 17Oct 9Jun 8Oct 9
2010Jun 17Aug 23May 24Sep 7
2009Jun 23Sep 9May 21Oct 1
2008no dataSep 1no dataSep 1
2004May 30no dataMay 25no data
1996Jun 19no dataJun 19no data
1995no dataAug 9no dataAug 19
1994Jul 5no dataJun 8no data
1993Jul 7Aug 17Jun 13Aug 25
1992Jul 14no dataMay 12no data
1991no dataAug 2no dataOct 4
1989no dataAug 26no dataAug 26
1988Jun 11Sep 11May 30Sep 12
1987Jun 2Sep 5May 22Sep 16
1986Jul 18Sep 10May 23Sep 16
1985Jun 26Aug 9Jun 26Aug 23
1984Jul 9Aug 20Jun 30Aug 21
1983Jul 16Sep 5May 16Sep 10
1982May 31Sep 11May 10Sep 11
1981Jul 8Sep 3Jul 8Sep 23
1980Jun 27Sep 4Jun 3Sep 22
1979Jun 20Sep 12May 31Oct 13
1978Jun 26Aug 17Jun 16Sep 17
1977May 30Aug 31May 30Sep 9
1976Jun 27Aug 27Jun 26Sep 7
1975Jun 28Aug 25May 26Sep 19
1973Jul 2Sep 2Jun 19Sep 3
1972Jun 19Sep 7Jun 12Sep 13
1971Jun 29Sep 15May 19Sep 16
1970Jun 30Sep 9May 15Sep 9
1969Jun 30Sep 4Jun 30Sep 15
1968Jul 1Aug 23Jun 30Sep 22
1967Jun 5Sep 12May 14Sep 13
1966Jul 3Aug 21Jun 25Sep 27
1965Jun 28Aug 29May 19Aug 31
1964Jun 20Aug 27May 7Aug 29
1963Jun 30Oct 10Apr 25Oct 13
1962Jun 7Sep 9Apr 30Sep 9
1961May 19Sep 3May 17Sep 21
1960Jun 21Aug 23Jun 21Aug 28
1959Jul 8Aug 21Jul 8Sep 28
1958Jul 3Aug 30May 14Sep 13
1957Jun 15Aug 2Apr 29Sep 14
1956Jun 30Aug 3Jun 5Sep 3
1955Jul 8Sep 17May 28Sep 22
1954Jul 23Aug 18Jun 18Sep 5
1953Jun 25Aug 25May 27Sep 25
1952Jun 16Sep 1Jun 13Sep 14

"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.