Frost history / Lutsen 3NNE, MN
Lutsen 3NNE, MN: frost dates by year
Last spring and first fall frost at NOAA station USC00214918, 1987 to 2004, measured from daily minimum temperatures.
Elevation 1,300 ft, 47.698, -90.666. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | May 23 | Sep 27 |
| Earliest | May 9 (1999) | Sep 18 (1991) |
| Latest | Jun 3 (2002) | Oct 5 (1990) |
| Trend | little change (less than half a day per decade) | 0.8 days earlier per decade |
| Years with data | 13 | 12 |
At 28°F (hard freeze) the median last spring date is May 17 and the median first fall date is Oct 3.
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 |
|---|---|---|---|---|
| 2004 | May 28 | Oct 2 | May 28 | Oct 2 |
| 2003 | May 31 | no data | May 4 | no data |
| 2002 | Jun 3 | Sep 24 | May 21 | Oct 7 |
| 2001 | May 12 | Sep 24 | May 12 | Sep 24 |
| 2000 | May 20 | Sep 24 | May 19 | Sep 24 |
| 1999 | May 9 | Sep 21 | May 9 | Oct 3 |
| 1998 | May 23 | Oct 2 | May 23 | Oct 21 |
| 1997 | May 22 | Oct 1 | May 12 | Oct 1 |
| 1996 | May 30 | Oct 3 | May 30 | Oct 10 |
| 1992 | no data | Sep 19 | no data | Sep 29 |
| 1991 | May 19 | Sep 18 | May 19 | Sep 27 |
| 1990 | May 30 | Oct 5 | May 6 | Oct 8 |
| 1988 | May 25 | no data | May 17 | no data |
| 1987 | May 23 | Oct 2 | May 3 | 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.