Frost history / White Rock Dam, MN
White Rock Dam, MN: frost dates by year
Last spring and first fall frost at NOAA station USC00218947, 2005 to 2025, measured from daily minimum temperatures.
Elevation 1,024 ft, 45.862, -96.565. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 8 | Oct 7 |
| Earliest | Apr 17 (2007) | Sep 15 (2007) |
| Latest | May 19 (2015) | Oct 22 (2025) |
| Trend | 5.0 days later per decade | 7.6 days later per decade |
| Years with data | 15 | 17 |
At 28°F (hard freeze) the median last spring date is Apr 30 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)
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 | no data | Oct 22 | no data | Oct 23 |
| 2022 | Apr 28 | no data | Apr 27 | no data |
| 2021 | May 11 | Oct 16 | May 11 | Oct 21 |
| 2020 | no data | Oct 2 | no data | Oct 2 |
| 2019 | May 10 | Oct 11 | May 7 | Oct 14 |
| 2017 | May 2 | Oct 10 | Apr 30 | Oct 10 |
| 2016 | May 15 | Oct 7 | May 14 | Oct 9 |
| 2015 | May 19 | Oct 7 | Apr 23 | Oct 16 |
| 2014 | May 16 | Oct 4 | May 3 | Oct 9 |
| 2013 | May 13 | Oct 16 | May 2 | Oct 25 |
| 2012 | Apr 17 | Sep 23 | Apr 12 | Sep 23 |
| 2011 | May 3 | Sep 15 | May 2 | Oct 19 |
| 2010 | May 8 | Oct 2 | Apr 8 | Oct 2 |
| 2009 | Apr 28 | Oct 9 | Apr 11 | Oct 9 |
| 2008 | no data | Oct 16 | no data | Oct 28 |
| 2007 | Apr 17 | Sep 15 | Apr 12 | Oct 28 |
| 2006 | Apr 26 | Oct 10 | Apr 26 | Oct 12 |
| 2005 | May 16 | Oct 6 | May 4 | Oct 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.