Frost history / Allerton, IA
Allerton, IA: frost dates by year
Last spring and first fall frost at NOAA station USC00130149, 1999 to 2025, measured from daily minimum temperatures.
Elevation 1,090 ft, 40.704, -93.370. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Apr 21 | Oct 15 |
| Earliest | Apr 8 (2017) | Sep 27 (2003) |
| Latest | May 5 (2013) | Oct 31 (2014) |
| Trend | little change (less than half a day per decade) | 6.2 days later per decade |
| Years with data | 25 | 21 |
At 28°F (hard freeze) the median last spring date is Apr 12 and the median first fall date is Oct 26.
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)
First fall frost (32°F)
Dots are single years. The gray line is the median, the green line the fitted trend.
Year by year
| Year | Last spring 32°F | First fall 32°F | Last spring 28°F | First fall 28°F |
|---|---|---|---|---|
| 2025 | Apr 9 | no data | Apr 9 | no data |
| 2024 | Apr 22 | Oct 16 | Mar 29 | Nov 23 |
| 2023 | Apr 25 | Oct 30 | Apr 24 | Oct 30 |
| 2022 | Apr 27 | Oct 8 | Apr 20 | Oct 18 |
| 2021 | Apr 23 | no data | Apr 23 | no data |
| 2020 | Apr 19 | Oct 19 | Apr 19 | Oct 26 |
| 2019 | Apr 28 | no data | Apr 14 | no data |
| 2018 | Apr 21 | Oct 15 | Apr 20 | Oct 21 |
| 2017 | Apr 8 | Oct 28 | Mar 24 | Oct 29 |
| 2016 | Apr 13 | Oct 13 | Apr 10 | Nov 19 |
| 2015 | Apr 24 | Oct 29 | Apr 4 | Nov 20 |
| 2014 | Apr 19 | Oct 31 | Apr 16 | Nov 1 |
| 2013 | May 5 | Oct 19 | Apr 25 | Oct 23 |
| 2012 | Apr 12 | Oct 6 | Apr 12 | Oct 6 |
| 2011 | May 4 | Oct 20 | Apr 6 | Nov 5 |
| 2010 | no data | Oct 29 | no data | Oct 29 |
| 2009 | Apr 15 | Oct 7 | Apr 6 | Oct 11 |
| 2008 | Apr 29 | Oct 27 | Apr 29 | Oct 28 |
| 2007 | Apr 15 | no data | Apr 13 | no data |
| 2006 | no data | Oct 12 | no data | Oct 12 |
| 2005 | May 3 | no data | Apr 2 | no data |
| 2004 | May 3 | Oct 2 | Apr 13 | Nov 5 |
| 2003 | Apr 11 | Sep 27 | Apr 10 | Sep 27 |
| 2002 | Apr 25 | Oct 7 | Apr 6 | Oct 20 |
| 2001 | Apr 19 | no data | Apr 1 | no data |
| 2000 | Apr 13 | Oct 6 | Apr 13 | Oct 7 |
| 1999 | Apr 17 | Oct 14 | Mar 27 | Oct 18 |
"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.