Last Frost Day

Frost history / Weiser, ID

Weiser, ID: frost dates by year

Last spring and first fall frost at NOAA station USC00109638, 1951 to 2009, measured from daily minimum temperatures.

Elevation 2,120 ft, 44.246, -116.970. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 10Oct 1
EarliestApr 16 (2001)Sep 7 (1992)
LatestJun 26 (1976)Oct 30 (2005)
Trend3.3 days earlier per decade3.3 days later per decade
Years with data4549

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 13.

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 14196019701980199020001951: May 311952: Apr 291953: May 101954: May 281955: Apr 271956: May 141957: Apr 271958: May 121959: May 111960: May 221961: May 51962: Jun 41963: Apr 211965: May 181966: Jun 41967: May 261969: May 31970: May 151971: May 201972: May 11974: May 211975: May 261976: Jun 261977: Apr 201978: Apr 231982: May 61983: May 141984: Jun 11985: May 131989: May 251992: Apr 231993: Apr 231997: May 21998: Apr 181999: May 162000: May 122001: Apr 162002: May 82003: Apr 192004: Apr 182005: Apr 172006: Apr 192007: May 42008: May 22009: May 13

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11196019701980199020001951: Sep 221952: Oct 61953: Sep 241954: Sep 291955: Sep 221956: Sep 221957: Oct 61958: Sep 211959: Oct 11960: Oct 81961: Sep 221962: Oct 71964: Sep 191965: Sep 171966: Oct 31967: Oct 61968: Oct 21969: Sep 151970: Sep 121971: Sep 181972: Sep 201973: Sep 261974: Sep 141975: Oct 81976: Oct 51978: Sep 191981: Oct 11982: Oct 21983: Sep 201984: Sep 241985: Sep 201986: Sep 201987: Sep 171989: Sep 131990: Oct 71992: Sep 71997: Oct 81998: Oct 171999: Oct 162000: Oct 62001: Oct 102002: Oct 122003: Oct 112004: Oct 192005: Oct 302006: Oct 212007: Oct 272008: Oct 92009: 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
2009May 13Oct 1Apr 4Oct 11
2008May 2Oct 9May 2Oct 23
2007May 4Oct 27Apr 11Oct 31
2006Apr 19Oct 21Mar 22Oct 22
2005Apr 17Oct 30Apr 16Nov 8
2004Apr 18Oct 19Mar 5Oct 25
2003Apr 19Oct 11Apr 7Oct 11
2002May 8Oct 12Apr 24Oct 13
2001Apr 16Oct 10Apr 15Nov 7
2000May 12Oct 6Mar 24Nov 3
1999May 16Oct 16May 10Oct 17
1998Apr 18Oct 17Mar 18Oct 17
1997May 2Oct 8Apr 12Oct 25
1993Apr 23no dataMar 12no data
1992Apr 23Sep 7Apr 22Sep 14
1990no dataOct 7no dataOct 7
1989May 25Sep 13May 19Oct 15
1987no dataSep 17no dataOct 11
1986no dataSep 20no dataSep 20
1985May 13Sep 20Apr 26Sep 29
1984Jun 1Sep 24Apr 30Sep 25
1983May 14Sep 20Apr 24Sep 21
1982May 6Oct 2May 5Oct 19
1981no dataOct 1no dataOct 5
1978Apr 23Sep 19Apr 22Oct 14
1977Apr 20no dataApr 20no data
1976Jun 26Oct 5Apr 24Oct 19
1975May 26Oct 8May 25Oct 24
1974May 21Sep 14May 19Sep 28
1973no dataSep 26no dataOct 3
1972May 1Sep 20Apr 30Sep 25
1971May 20Sep 18Apr 27Sep 18
1970May 15Sep 12May 11Sep 14
1969May 3Sep 15May 2Oct 5
1968no dataOct 2no dataOct 3
1967May 26Oct 6May 11Oct 15
1966Jun 4Oct 3May 23Oct 9
1965May 18Sep 17May 10Sep 19
1964no dataSep 19no dataOct 2
1963Apr 21no dataApr 21no data
1962Jun 4Oct 7Apr 30Nov 6
1961May 5Sep 22Apr 20Oct 2
1960May 22Oct 8May 22Oct 13
1959May 11Oct 1May 3Oct 31
1958May 12Sep 21Mar 31Oct 21
1957Apr 27Oct 6Apr 7Oct 18
1956May 14Sep 22Apr 9Oct 22
1955Apr 27Sep 22Apr 27Sep 30
1954May 28Sep 29May 2Sep 30
1953May 10Sep 24Apr 15Oct 3
1952Apr 29Oct 6Apr 11Oct 15
1951May 31Sep 22Apr 22Oct 26

"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.