Last Frost Day

Frost history / Manchester #2, IA

Manchester #2, IA: frost dates by year

Last spring and first fall frost at NOAA station USC00135086, 1976 to 2025, measured from daily minimum temperatures.

Elevation 990 ft, 42.473, -91.452. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 4Oct 3
EarliestApr 17 (2009)Sep 13 (2014)
LatestMay 29 (2021)Oct 23 (2025)
Trendlittle change (less than half a day per decade)2.8 days later per decade
Years with data4750

At 28°F (hard freeze) the median last spring date is Apr 21 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 14198019902000201020201977: Apr 281978: May 61979: May 121980: May 141981: May 121982: Apr 281983: May 81984: Apr 241986: May 31987: Apr 281988: Apr 291989: May 111990: May 121991: May 21992: May 271993: Apr 231994: May 31995: Apr 261996: May 131997: May 161998: Apr 181999: Apr 192000: Apr 232002: May 212003: Apr 232004: May 52005: May 162006: May 72007: Apr 182008: May 42009: Apr 172010: May 92011: May 172012: Apr 212013: May 132014: May 172015: May 12016: May 182017: May 42018: Apr 302019: May 122020: May 122021: May 292022: May 42023: Apr 272024: Apr 232025: Apr 17

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 11198019902000201020201976: Sep 241977: Oct 31978: Oct 81979: Sep 221980: Sep 261981: Sep 281982: Sep 211983: Sep 231984: Sep 161985: Sep 271986: Oct 61987: Oct 31988: Oct 31989: Sep 231990: Sep 301991: Sep 201992: Sep 291993: Sep 301994: Oct 101995: Sep 221996: Oct 31997: Oct 151998: Oct 141999: Oct 62000: Oct 62001: Oct 62002: Oct 132003: Sep 292004: Sep 292005: Oct 82006: Oct 62007: Sep 152008: Oct 42009: Oct 102010: Oct 32011: Sep 152012: Sep 232013: Oct 132014: Sep 132015: Oct 142016: Oct 132017: Oct 162018: Sep 292019: Oct 122020: Oct 22021: Oct 222022: Sep 282023: Oct 102024: Oct 162025: 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 16Oct 24
2024Apr 23Oct 16Apr 22Oct 16
2023Apr 27Oct 10Apr 27Oct 11
2022May 4Sep 28Apr 20Oct 8
2021May 29Oct 22Apr 25Oct 23
2020May 12Oct 2May 12Oct 26
2019May 12Oct 12Apr 28Oct 14
2018Apr 30Sep 29Apr 30Oct 18
2017May 4Oct 16Apr 28Oct 29
2016May 18Oct 13Apr 13Oct 13
2015May 1Oct 14Apr 24Oct 17
2014May 17Sep 13Apr 19Oct 11
2013May 13Oct 13Apr 20Oct 22
2012Apr 21Sep 23Apr 13Sep 23
2011May 17Sep 15May 4Oct 21
2010May 9Oct 3Apr 9Oct 22
2009Apr 17Oct 10Apr 16Oct 10
2008May 4Oct 4Apr 15Oct 21
2007Apr 18Sep 15Apr 16Oct 25
2006May 7Oct 6Apr 26Oct 12
2005May 16Oct 8May 4Oct 26
2004May 5Sep 29May 3Oct 5
2003Apr 23Sep 29Apr 11Oct 1
2002May 21Oct 13Apr 26Oct 16
2001no dataOct 6no dataOct 17
2000Apr 23Oct 6Apr 13Oct 7
1999Apr 19Oct 6Mar 27Oct 18
1998Apr 18Oct 14Mar 25Oct 22
1997May 16Oct 15Apr 18Oct 20
1996May 13Oct 3May 2Oct 19
1995Apr 26Sep 22Apr 6Sep 23
1994May 3Oct 10May 2Oct 10
1993Apr 23Sep 30Apr 22Oct 10
1992May 27Sep 29May 6Sep 29
1991May 2Sep 20Apr 1Sep 20
1990May 12Sep 30Apr 19Oct 11
1989May 11Sep 23May 7Sep 24
1988Apr 29Oct 3Apr 29Oct 5
1987Apr 28Oct 3Apr 7Oct 3
1986May 3Oct 6Apr 22Oct 15
1985no dataSep 27no dataOct 6
1984Apr 24Sep 16Apr 7Sep 16
1983May 8Sep 23Apr 25Sep 23
1982Apr 28Sep 21Apr 28Sep 22
1981May 12Sep 28Apr 21Oct 2
1980May 14Sep 26May 9Oct 5
1979May 12Sep 22Apr 15Oct 13
1978May 6Oct 8Mar 29Oct 8
1977Apr 28Oct 3Apr 8Oct 13
1976no dataSep 24no dataSep 24

"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.