Last Frost Day

Frost history / Shoup, ID

Shoup, ID: frost dates by year

Last spring and first fall frost at NOAA station USC00108395, 1966 to 2011, measured from daily minimum temperatures.

Elevation 3,400 ft, 45.377, -114.278. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 14Oct 3
EarliestApr 15 (1980)Sep 14 (1970)
LatestJul 5 (1999)Oct 23 (1975)
Trend1.8 days earlier per decade1.5 days later per decade
Years with data4037

At 28°F (hard freeze) the median last spring date is Apr 30 and the median first fall date is Oct 11.

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 14197019801990200020101966: Jun 41967: May 261968: May 161969: May 31970: May 151971: May 191972: May 31973: Jun 31974: May 221975: May 261976: May 151977: May 301978: May 41979: May 301980: Apr 151982: May 301983: May 141984: Jun 11985: May 141986: May 231988: May 181989: May 261990: May 161991: May 91993: May 91994: Apr 291995: May 141996: May 141997: May 21998: Apr 261999: Jul 52002: May 112003: May 202004: May 12005: May 302006: May 102007: May 62008: May 132010: May 142011: May 6

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11197019801990200020101966: Oct 41967: Oct 41968: Oct 31969: Oct 51970: Sep 141971: Sep 151972: Sep 261973: Oct 31974: Oct 61975: Oct 231976: Oct 71977: Oct 21978: Sep 201979: Oct 31980: Sep 221981: Sep 231982: Sep 151984: Sep 141985: Sep 231986: Sep 231987: Oct 101988: Oct 121990: Oct 71991: Sep 231994: Oct 81995: Sep 211997: Oct 61998: Oct 42001: Oct 52002: Oct 22003: Sep 182004: Oct 112005: Oct 52006: Oct 102007: Sep 302008: Oct 82010: Oct 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
2011May 6no dataApr 25no data
2010May 14Oct 13May 5Nov 10
2008May 13Oct 8May 2Oct 9
2007May 6Sep 30Apr 13Oct 27
2006May 10Oct 10Apr 19Oct 21
2005May 30Oct 5May 30Nov 9
2004May 1Oct 11Apr 29Oct 25
2003May 20Sep 18Apr 27Oct 25
2002May 11Oct 2May 9Oct 12
2001no dataOct 5no dataOct 26
1999Jul 5no dataJun 10no data
1998Apr 26Oct 4Apr 18Oct 5
1997May 2Oct 6Apr 13Oct 25
1996May 14no dataMay 5no data
1995May 14Sep 21Apr 17Oct 2
1994Apr 29Oct 8Apr 29Oct 24
1993May 9no dataApr 29no data
1991May 9Sep 23Apr 13Oct 5
1990May 16Oct 7May 8Oct 7
1989May 26no dataMay 20no data
1988May 18Oct 12Apr 10Oct 27
1987no dataOct 10no dataOct 11
1986May 23Sep 23Apr 30Oct 11
1985May 14Sep 23May 13Sep 29
1984Jun 1Sep 14May 7Sep 28
1983May 14no dataMay 14no data
1982May 30Sep 15May 5Oct 6
1981no dataSep 23no dataOct 4
1980Apr 15Sep 22Apr 8Oct 10
1979May 30Oct 3Apr 20Oct 30
1978May 4Sep 20Apr 13Oct 22
1977May 30Oct 2Apr 19Oct 11
1976May 15Oct 7Apr 19Oct 18
1975May 26Oct 23May 2Oct 23
1974May 22Oct 6May 16Oct 6
1973Jun 3Oct 3May 11Oct 3
1972May 3Sep 26May 1Sep 26
1971May 19Sep 15Apr 13Sep 18
1970May 15Sep 14May 14Sep 25
1969May 3Oct 5Apr 27Oct 5
1968May 16Oct 3May 8Oct 9
1967May 26Oct 4May 1Oct 20
1966Jun 4Oct 4Apr 29Oct 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.