Frost history / Ely 25E, MN
Ely 25E, MN: frost dates by year
Last spring and first fall frost at NOAA station USC00212555, 1999 to 2024, measured from daily minimum temperatures.
Elevation 1,444 ft, 47.972, -91.449. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 20 | Sep 29 |
| Earliest | May 2 (2024) | Aug 30 (2009) |
| Latest | Jun 2 (2019) | Oct 22 (2023) |
| Trend | 1.1 days later per decade | 6.1 days later per decade |
| Years with data | 15 | 18 |
At 28°F (hard freeze) the median last spring date is May 7 and the median first fall date is Oct 10.
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 |
|---|---|---|---|---|
| 2024 | May 2 | no data | Apr 25 | no data |
| 2023 | no data | Oct 22 | no data | Oct 28 |
| 2022 | no data | Sep 28 | no data | Sep 28 |
| 2021 | May 29 | Oct 21 | May 29 | Oct 26 |
| 2020 | May 13 | Sep 17 | May 13 | Sep 18 |
| 2019 | Jun 2 | Oct 12 | May 7 | Oct 25 |
| 2018 | May 20 | no data | May 12 | no data |
| 2017 | May 20 | no data | May 19 | no data |
| 2016 | May 18 | Oct 9 | May 17 | Oct 9 |
| 2015 | Jun 1 | Sep 29 | May 13 | Oct 16 |
| 2012 | no data | Sep 25 | no data | Oct 7 |
| 2011 | May 27 | Sep 15 | May 3 | Oct 21 |
| 2010 | no data | Sep 25 | no data | Oct 29 |
| 2009 | May 31 | Aug 30 | May 4 | Oct 10 |
| 2008 | no data | Oct 3 | no data | Oct 21 |
| 2006 | May 22 | Oct 1 | Apr 25 | Oct 10 |
| 2005 | no data | Oct 7 | no data | Oct 27 |
| 2003 | May 4 | Sep 29 | May 2 | Oct 2 |
| 2002 | May 22 | Oct 3 | May 10 | Oct 7 |
| 2001 | May 12 | no data | Apr 27 | no data |
| 2000 | May 19 | Sep 24 | Apr 22 | Sep 28 |
| 1999 | no data | Sep 21 | no data | Oct 3 |
"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.