Last Frost Day

Frost history / Sioux City Gateway Ap, IA

Sioux City Gateway Ap, IA: frost dates by year

Last spring and first fall frost at NOAA station USW00014943, 1951 to 2024, measured from daily minimum temperatures.

Elevation 1,095 ft, 42.391, -96.379. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 28Oct 5
EarliestApr 6 (1977)Sep 15 (2007)
LatestMay 22 (2022)Oct 29 (1963)
Trend0.9 days later per decade0.8 days earlier per decade
Years with data7474

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

Mar 31Apr 15Apr 30May 15May 3019601970198019902000201020201951: Apr 261952: Apr 161953: Apr 271954: May 71955: Apr 71956: Apr 301957: Apr 141958: Apr 291959: Apr 221960: Apr 301961: May 21962: Apr 161963: May 221964: Apr 91965: Apr 281966: May 11967: May 41968: May 51969: May 121970: May 21971: Apr 291972: Apr 151973: Apr 271974: Apr 161975: Apr 201976: May 71977: Apr 61978: May 31979: May 41980: May 81981: May 111982: Apr 221983: May 151984: Apr 61985: Apr 91986: Apr 221987: Apr 231988: Apr 281989: May 71990: May 11991: Apr 101992: Apr 271993: Apr 161994: May 11995: Apr 271996: Apr 301997: May 201998: Apr 191999: Apr 182000: Apr 212001: Apr 242002: May 192003: Apr 222004: May 32005: May 42006: Apr 262007: Apr 152008: Apr 292009: Apr 142010: May 92011: May 32012: Apr 232013: May 122014: May 172015: Apr 232016: Apr 122017: Apr 282018: Apr 232019: Apr 282020: May 112021: May 112022: May 222023: May 32024: Apr 24

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 281952: Oct 51953: Oct 261954: Oct 271955: Oct 81956: Sep 301957: Oct 241958: Oct 11959: Oct 91960: Oct 161961: Sep 281962: Oct 231963: Oct 291964: Oct 81965: Sep 241966: Oct 51967: Sep 281968: Oct 41969: Oct 131970: Oct 91971: Sep 191972: Oct 71973: Oct 281974: Sep 221975: Sep 251976: Oct 61977: Oct 91978: Oct 71979: Oct 121980: Oct 31981: Oct 21982: Oct 201983: Sep 231984: Sep 261985: Sep 261986: Oct 121987: Oct 31988: Oct 41989: Sep 231990: Oct 101991: Sep 191992: Oct 111993: Sep 271994: Oct 241995: Sep 221996: Oct 31997: Sep 211998: Oct 131999: Sep 212000: Sep 212001: Sep 242002: Oct 62003: Sep 252004: Oct 12005: Sep 292006: Sep 202007: Sep 152008: Oct 142009: Oct 42010: Oct 152011: Sep 152012: Sep 222013: Oct 132014: Oct 32015: Oct 162016: Oct 122017: Oct 112018: Oct 122019: Oct 112020: Oct 12021: Oct 212022: Oct 72023: Oct 72024: Oct 7

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
2024Apr 24Oct 7Apr 21Oct 15
2023May 3Oct 7Apr 24Oct 27
2022May 22Oct 7Apr 26Oct 7
2021May 11Oct 21Apr 22Oct 23
2020May 11Oct 1Apr 17Oct 23
2019Apr 28Oct 11Apr 14Oct 14
2018Apr 23Oct 12Apr 19Oct 15
2017Apr 28Oct 11Apr 11Oct 27
2016Apr 12Oct 12Apr 12Oct 13
2015Apr 23Oct 16Apr 22Nov 7
2014May 17Oct 3Apr 15Oct 31
2013May 12Oct 13Apr 25Oct 24
2012Apr 23Sep 22Apr 11Sep 23
2011May 3Sep 15May 3Oct 17
2010May 9Oct 15Apr 8Oct 28
2009Apr 14Oct 4Apr 14Oct 9
2008Apr 29Oct 14Apr 28Oct 16
2007Apr 15Sep 15Apr 15Oct 26
2006Apr 26Sep 20Apr 26Oct 12
2005May 4Sep 29May 3Oct 22
2004May 3Oct 1Apr 13Oct 2
2003Apr 22Sep 25Apr 22Sep 30
2002May 19Oct 6Apr 9Oct 7
2001Apr 24Sep 24Apr 18Oct 6
2000Apr 21Sep 21Apr 9Oct 6
1999Apr 18Sep 21Apr 18Oct 1
1998Apr 19Oct 13Apr 17Nov 5
1997May 20Sep 21May 13Oct 20
1996Apr 30Oct 3Apr 30Oct 27
1995Apr 27Sep 22Apr 13Sep 22
1994May 1Oct 24May 1Oct 25
1993Apr 16Sep 27Apr 5Oct 10
1992Apr 27Oct 11Apr 27Oct 17
1991Apr 10Sep 19Apr 10Oct 18
1990May 1Oct 10May 1Oct 10
1989May 7Sep 23Apr 15Oct 18
1988Apr 28Oct 4Apr 19Oct 5
1987Apr 23Oct 3Apr 5Oct 3
1986Apr 22Oct 12Apr 22Oct 13
1985Apr 9Sep 26Apr 9Oct 30
1984Apr 6Sep 26Apr 1Sep 26
1983May 15Sep 23Apr 19Oct 14
1982Apr 22Oct 20Apr 22Oct 21
1981May 11Oct 2Apr 15Oct 2
1980May 8Oct 3Apr 14Oct 12
1979May 4Oct 12Apr 28Oct 12
1978May 3Oct 7Apr 21Oct 7
1977Apr 6Oct 9Apr 6Oct 16
1976May 7Oct 6May 3Oct 6
1975Apr 20Sep 25Apr 4Oct 25
1974Apr 16Sep 22Apr 5Oct 1
1973Apr 27Oct 28Apr 11Oct 29
1972Apr 15Oct 7Apr 8Oct 18
1971Apr 29Sep 19Apr 6Oct 31
1970May 2Oct 9Apr 4Oct 10
1969May 12Oct 13Mar 31Oct 14
1968May 5Oct 4Apr 5Oct 4
1967May 4Sep 28May 2Oct 11
1966May 1Oct 5Apr 21Oct 16
1965Apr 28Sep 24Mar 30Oct 24
1964Apr 9Oct 8Apr 9Oct 9
1963May 22Oct 29Apr 4Oct 29
1962Apr 16Oct 23Apr 15Oct 25
1961May 2Sep 28Apr 18Oct 1
1960Apr 30Oct 16Apr 10Oct 19
1959Apr 22Oct 9Apr 13Oct 9
1958Apr 29Oct 1Apr 29Oct 1
1957Apr 14Oct 24Apr 14Oct 25
1956Apr 30Sep 30Apr 24Nov 8
1955Apr 7Oct 8Mar 28Oct 24
1954May 7Oct 27Apr 8Oct 30
1953Apr 27Oct 26Apr 20Nov 4
1952Apr 16Oct 5Apr 15Oct 5
1951Apr 26Sep 28Apr 23Sep 28

"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.