Last Frost Day

Frost history / Little Sioux 2 Nw, IA

Little Sioux 2 Nw, IA: frost dates by year

Last spring and first fall frost at NOAA station USC00134874, 2003 to 2025, measured from daily minimum temperatures.

Elevation 1,025 ft, 41.826, -96.051. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 4Oct 5
EarliestApr 16 (2007)Sep 15 (2007)
LatestMay 22 (2022)Oct 22 (2025)
Trend2.2 days later per decade11.2 days later per decade
Years with data2322

At 28°F (hard freeze) the median last spring date is Apr 24 and the median first fall date is Oct 14.

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 30201020202003: Apr 262004: May 42005: May 52006: Apr 272007: Apr 162008: May 42009: Apr 292010: May 92011: May 42012: Apr 242013: May 132014: May 182015: Apr 282016: May 142017: Apr 212018: Apr 292019: May 112020: May 122021: May 62022: May 222023: May 42024: Apr 252025: Apr 19

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27201020202003: Sep 262004: Oct 22005: Sep 292006: Sep 202007: Sep 152009: Sep 302010: Oct 32011: Sep 152012: Sep 182013: Oct 132014: Oct 42015: Oct 162016: Oct 72017: Oct 112018: Oct 152019: Oct 122020: Oct 22021: Oct 222022: Oct 82023: Oct 72024: Oct 142025: Oct 22

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 19Oct 22Apr 9Oct 23
2024Apr 25Oct 14Apr 22Oct 15
2023May 4Oct 7Apr 24Oct 28
2022May 22Oct 8Apr 27Oct 8
2021May 6Oct 22Apr 23Oct 22
2020May 12Oct 2May 11Oct 2
2019May 11Oct 12Apr 20Oct 12
2018Apr 29Oct 15Apr 25Oct 15
2017Apr 21Oct 11Apr 12Oct 28
2016May 14Oct 7Apr 12Oct 13
2015Apr 28Oct 16Apr 24Oct 17
2014May 18Oct 4May 16Oct 11
2013May 13Oct 13May 3Oct 23
2012Apr 24Sep 18Apr 12Sep 23
2011May 4Sep 15May 4Oct 19
2010May 9Oct 3Apr 18Oct 29
2009Apr 29Sep 30Apr 15Oct 10
2008May 4no dataApr 29no data
2007Apr 16Sep 15Apr 13Oct 28
2006Apr 27Sep 20Apr 27Oct 12
2005May 5Sep 29May 1Oct 7
2004May 4Oct 2May 3Oct 2
2003Apr 26Sep 26Apr 10Oct 1

"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.