Last Frost Day

Frost history / Belle Plaine, IA

Belle Plaine, IA: frost dates by year

Last spring and first fall frost at NOAA station USC00130600, 1951 to 2025, measured from daily minimum temperatures.

Elevation 810 ft, 41.881, -92.276. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 29Oct 6
EarliestApr 7 (1987)Sep 12 (1955)
LatestMay 23 (1963)Oct 30 (1973)
Trendlittle change (less than half a day per decade)0.8 days later per decade
Years with data7070

At 28°F (hard freeze) the median last spring date is Apr 18 and the median first fall date is Oct 19.

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 3019601970198019902000201020201951: Apr 231952: Apr 161953: May 131954: May 71955: Apr 81956: May 161957: May 41958: May 51959: Apr 221960: May 11961: May 31962: Apr 191963: May 231964: Apr 151965: Apr 191966: May 141967: May 71968: Apr 251969: Apr 291970: May 21971: May 31972: Apr 251973: Apr 281974: May 61975: Apr 131976: May 81977: Apr 291978: May 61979: May 11980: May 91981: May 111982: Apr 211983: Apr 201984: Apr 221985: Apr 91986: Apr 221987: Apr 71988: Apr 291989: May 71990: Apr 181991: Apr 101993: Apr 221994: May 31995: Apr 271996: May 21997: May 161998: Apr 171999: Apr 132000: Apr 212001: Apr 242002: May 192003: Apr 232004: May 152005: May 52006: May 62007: Apr 172008: Apr 302009: Apr 232010: May 92011: May 52012: Apr 212016: Apr 132017: Apr 82018: Apr 292019: May 102020: May 122021: May 122023: May 32024: Apr 222025: Apr 17

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 281952: Oct 31953: Sep 221954: Oct 171955: Sep 121956: Sep 201957: Oct 101958: Oct 11959: Oct 91960: Oct 191961: Sep 281962: Sep 201963: Oct 281964: Oct 61965: Oct 121966: Oct 171967: Sep 291968: Oct 41969: Oct 141970: Oct 101971: Oct 121972: Sep 301973: Oct 301974: Sep 221975: Sep 261976: Oct 61977: Oct 61978: Oct 81979: Oct 51980: Sep 261981: Oct 21982: Oct 211983: Sep 221984: Sep 261985: Oct 11986: Oct 61987: Oct 31988: Oct 51989: Sep 241990: Oct 111991: Sep 191993: Oct 101994: Oct 101995: Sep 221996: Oct 41997: Oct 151998: Oct 201999: Oct 142000: Oct 62001: Oct 62002: Sep 242003: Sep 292004: Oct 22005: Oct 82006: Oct 122007: Sep 152008: Oct 162009: Oct 52011: Sep 152012: Sep 232015: Oct 172016: Oct 132017: Oct 162018: Oct 152019: Oct 122020: Oct 42021: Oct 172023: Oct 102024: Oct 152025: Oct 23

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 17Oct 23Apr 17Oct 24
2024Apr 22Oct 15Apr 6Oct 16
2023May 3Oct 10Apr 26Oct 30
2021May 12Oct 17May 12Oct 23
2020May 12Oct 4May 9Oct 20
2019May 10Oct 12Apr 28Oct 25
2018Apr 29Oct 15Apr 29Oct 21
2017Apr 8Oct 16Apr 7Oct 29
2016Apr 13Oct 13Apr 13Nov 12
2015no dataOct 17no dataOct 17
2012Apr 21Sep 23Apr 12Sep 23
2011May 5Sep 15May 4Oct 2
2010May 9no dataMay 9no data
2009Apr 23Oct 5Apr 22Oct 10
2008Apr 30Oct 16Apr 29Oct 28
2007Apr 17Sep 15Apr 16Oct 25
2006May 6Oct 12Apr 26Oct 13
2005May 5Oct 8May 4Oct 26
2004May 15Oct 2May 3Oct 5
2003Apr 23Sep 29Apr 11Sep 30
2002May 19Sep 24Apr 6Oct 16
2001Apr 24Oct 6Apr 19Oct 6
2000Apr 21Oct 6Apr 13Oct 7
1999Apr 13Oct 14Mar 27Oct 18
1998Apr 17Oct 20Mar 25Nov 4
1997May 16Oct 15Apr 18Oct 22
1996May 2Oct 4Apr 10Oct 19
1995Apr 27Sep 22Apr 7Oct 22
1994May 3Oct 10Apr 8Oct 26
1993Apr 22Oct 10Apr 5Oct 11
1991Apr 10Sep 19Apr 1Sep 20
1990Apr 18Oct 11Apr 18Oct 19
1989May 7Sep 24May 7Sep 24
1988Apr 29Oct 5Apr 29Oct 5
1987Apr 7Oct 3Apr 5Oct 3
1986Apr 22Oct 6Apr 22Nov 2
1985Apr 9Oct 1Apr 9Nov 4
1984Apr 22Sep 26Apr 22Sep 29
1983Apr 20Sep 22Apr 19Nov 5
1982Apr 21Oct 21Apr 21Oct 21
1981May 11Oct 2Apr 6Oct 19
1980May 9Sep 26Apr 16Oct 12
1979May 1Oct 5Apr 7Oct 13
1978May 6Oct 8Mar 27Oct 26
1977Apr 29Oct 6Apr 29Oct 16
1976May 8Oct 6Apr 12Oct 6
1975Apr 13Sep 26Apr 12Oct 2
1974May 6Sep 22Apr 24Oct 2
1973Apr 28Oct 30Apr 13Nov 5
1972Apr 25Sep 30Apr 8Sep 30
1971May 3Oct 12Apr 14Nov 4
1970May 2Oct 10Apr 4Oct 16
1969Apr 29Oct 14Apr 29Oct 14
1968Apr 25Oct 4Apr 15Oct 4
1967May 7Sep 29Apr 24Sep 29
1966May 14Oct 17May 10Oct 17
1965Apr 19Oct 12Apr 19Oct 24
1964Apr 15Oct 6Apr 9Oct 6
1963May 23Oct 28Apr 24Oct 29
1962Apr 19Sep 20Apr 16Oct 24
1961May 3Sep 28May 2Oct 26
1960May 1Oct 19Apr 18Oct 20
1959Apr 22Oct 9Apr 22Oct 12
1958May 5Oct 1Apr 29Oct 1
1957May 4Oct 10Apr 14Oct 19
1956May 16Sep 20Apr 30Oct 9
1955Apr 8Sep 12Apr 7Oct 19
1954May 7Oct 17Apr 12Oct 30
1953May 13Sep 22Apr 20Oct 27
1952Apr 16Oct 3Apr 11Oct 3
1951Apr 23Sep 28Apr 23Oct 31

"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.