Frost history / St Marie, MT
St Marie, MT: frost dates by year
Last spring and first fall frost at NOAA station USW00094010, 1959 to 2024, measured from daily minimum temperatures.
Elevation 2,756 ft, 48.409, -106.514. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 14 | Sep 27 |
| Earliest | Apr 19 (1964) | Sep 8 (2020) |
| Latest | Jun 4 (1998) | Oct 27 (1963) |
| Trend | 0.5 days later per decade | little change (less than half a day per decade) |
| Years with data | 32 | 34 |
At 28°F (hard freeze) the median last spring date is Apr 27 and the median first fall date is Oct 5.
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 4 | Oct 13 | Apr 21 | Oct 13 |
| 2023 | Apr 30 | Oct 6 | Apr 24 | Oct 6 |
| 2022 | May 22 | Oct 7 | May 22 | Oct 16 |
| 2021 | May 21 | Oct 11 | Apr 24 | Oct 14 |
| 2020 | May 12 | Sep 8 | May 11 | Sep 8 |
| 2019 | May 19 | Oct 1 | May 9 | Oct 9 |
| 2018 | May 1 | Sep 21 | Apr 19 | Sep 28 |
| 2017 | May 18 | Sep 26 | Apr 25 | Oct 4 |
| 2016 | May 15 | Sep 13 | Apr 17 | Oct 7 |
| 2015 | May 29 | Oct 6 | May 19 | Oct 28 |
| 2014 | May 14 | Sep 12 | May 14 | Oct 3 |
| 2013 | May 13 | Oct 4 | May 2 | Oct 4 |
| 2012 | May 14 | Oct 4 | Apr 20 | Oct 5 |
| 2011 | May 14 | Sep 14 | Apr 21 | Oct 14 |
| 2007 | Apr 23 | Sep 14 | Apr 13 | Oct 21 |
| 2006 | May 11 | no data | May 11 | no data |
| 2005 | May 14 | no data | May 14 | no data |
| 2004 | no data | Oct 1 | no data | Oct 1 |
| 2003 | May 19 | Sep 24 | Apr 29 | Oct 16 |
| 2002 | no data | Sep 23 | no data | Sep 23 |
| 2001 | May 21 | Oct 5 | Apr 22 | Oct 5 |
| 2000 | May 12 | Sep 22 | Apr 16 | Sep 23 |
| 1999 | May 17 | Sep 27 | May 17 | Oct 1 |
| 1998 | Jun 4 | Oct 6 | Apr 19 | Oct 13 |
| 1997 | May 19 | Sep 19 | Apr 15 | Oct 9 |
| 1996 | May 12 | Sep 24 | May 10 | Oct 2 |
| 1995 | no data | Sep 19 | no data | Sep 20 |
| 1967 | May 13 | Oct 7 | May 12 | Oct 20 |
| 1966 | May 12 | Oct 4 | May 11 | Oct 14 |
| 1965 | May 26 | Sep 10 | Apr 19 | Sep 16 |
| 1964 | Apr 19 | Sep 11 | Apr 17 | Oct 18 |
| 1963 | May 21 | Oct 27 | May 3 | Oct 28 |
| 1962 | May 8 | Sep 9 | Apr 13 | Sep 9 |
| 1961 | May 9 | Sep 13 | Apr 29 | Sep 27 |
| 1960 | May 7 | Oct 15 | Apr 30 | Oct 18 |
| 1959 | no data | Sep 28 | no data | Sep 29 |
"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.