Last Frost Day

Frost history / Winona, MN

Winona, MN: frost dates by year

Last spring and first fall frost at NOAA station USC00219067, 1951 to 2009, measured from daily minimum temperatures.

Elevation 652 ft, 44.042, -91.636. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 27Oct 7
EarliestMar 27 (1999)Sep 13 (1975)
LatestMay 30 (1965)Nov 1 (1994)
Trend2.2 days earlier per decade0.8 days later per decade
Years with data5052

At 28°F (hard freeze) the median last spring date is Apr 15 and the median first fall date is Oct 20.

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 16Mar 31Apr 15Apr 30May 15May 30Jun 14196019701980199020001951: Apr 191952: Apr 161953: May 131954: May 41955: Apr 81956: May 11957: Apr 151958: Apr 301959: Apr 221960: Apr 191961: May 11962: Apr 291963: May 231964: Apr 161965: May 301966: May 111967: May 121968: May 61969: May 121970: Apr 221971: May 31972: Apr 251973: May 171975: Apr 231977: Apr 91978: May 31979: May 41980: Apr 251981: May 111982: Apr 271987: Apr 61989: May 61990: Apr 171992: Apr 271994: May 21995: Apr 221996: Apr 281997: Apr 171998: Apr 41999: Mar 272000: Apr 122001: Apr 182002: May 32003: Apr 102004: May 32005: May 42006: Apr 92007: Apr 152008: Apr 292009: Apr 15

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11196019701980199020001951: Oct 241952: Oct 51953: Oct 271954: Oct 71955: Oct 151956: Sep 201957: Sep 271958: Oct 11959: Oct 131960: Oct 181961: Sep 281962: Oct 241963: Oct 291964: Oct 91965: Oct 41966: Oct 171967: Sep 291968: Oct 41969: Oct 141970: Oct 101971: Oct 121972: Sep 301973: Sep 181974: Sep 221975: Sep 131977: Oct 71978: Oct 81979: Oct 71980: Oct 51981: Oct 21982: Oct 201986: Oct 61989: Oct 41990: Oct 181991: Sep 201992: Sep 291993: Oct 21994: Nov 11995: Oct 161996: Oct 31997: Oct 221998: Oct 221999: Oct 42000: Oct 72001: Oct 72002: Oct 162003: Oct 22004: Oct 52005: Oct 282006: Oct 122007: Oct 232008: Oct 21

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
2009Apr 15no dataApr 8no data
2008Apr 29Oct 21Apr 29Oct 28
2007Apr 15Oct 23Apr 10Nov 7
2006Apr 9Oct 12Apr 9Oct 12
2005May 4Oct 28May 3Nov 10
2004May 3Oct 5Apr 13Nov 8
2003Apr 10Oct 2Apr 9Oct 2
2002May 3Oct 16Apr 6Oct 16
2001Apr 18Oct 7Apr 1Oct 7
2000Apr 12Oct 7Apr 12Oct 9
1999Mar 27Oct 4Mar 27Oct 24
1998Apr 4Oct 22Mar 24Nov 4
1997Apr 17Oct 22Apr 17Oct 27
1996Apr 28Oct 3Apr 9Oct 30
1995Apr 22Oct 16Apr 9Nov 2
1994May 2Nov 1Apr 8Nov 1
1993no dataOct 2no dataOct 13
1992Apr 27Sep 29Apr 12Sep 29
1991no dataSep 20no dataOct 7
1990Apr 17Oct 18Apr 12Oct 18
1989May 6Oct 4May 6Oct 19
1987Apr 6no dataApr 6no data
1986no dataOct 6no dataOct 18
1982Apr 27Oct 20Apr 22Oct 21
1981May 11Oct 2Apr 15Oct 19
1980Apr 25Oct 5Apr 24Oct 27
1979May 4Oct 7May 1Oct 26
1978May 3Oct 8Apr 22Oct 8
1977Apr 9Oct 7Apr 9Oct 16
1975Apr 23Sep 13Apr 23Oct 2
1974no dataSep 22no dataSep 22
1973May 17Sep 18May 4Nov 4
1972Apr 25Sep 30Apr 10Sep 30
1971May 3Oct 12Apr 14Nov 4
1970Apr 22Oct 10Apr 10Oct 16
1969May 12Oct 14Apr 1Oct 22
1968May 6Oct 4Apr 6Oct 25
1967May 12Sep 29May 3Oct 19
1966May 11Oct 17May 11Oct 25
1965May 30Oct 4Apr 29Oct 13
1964Apr 16Oct 9Apr 15Oct 9
1963May 23Oct 29May 1Nov 2
1962Apr 29Oct 24Apr 17Oct 24
1961May 1Sep 28Apr 17Oct 20
1960Apr 19Oct 18Apr 19Oct 20
1959Apr 22Oct 13Apr 21Oct 17
1958Apr 30Oct 1Apr 30Oct 31
1957Apr 15Sep 27Apr 15Oct 20
1956May 1Sep 20May 1Oct 10
1955Apr 8Oct 15Apr 8Nov 3
1954May 4Oct 7May 4Oct 19
1953May 13Oct 27Apr 19Oct 28
1952Apr 16Oct 5Apr 13Oct 5
1951Apr 19Oct 24Apr 17Oct 27

"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.