Frost history / Alton, MO
Alton, MO: frost dates by year
Last spring and first fall frost at NOAA station USC00230127, 1963 to 2025, measured from daily minimum temperatures.
Elevation 813 ft, 36.692, -91.399. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Apr 16 | Oct 18 |
| Earliest | Mar 31 (1969) | Sep 23 (1995) |
| Latest | May 9 (1976) | Nov 5 (2004) |
| Trend | little change (less than half a day per decade) | 1.4 days later per decade |
| Years with data | 30 | 29 |
At 28°F (hard freeze) the median last spring date is Apr 4 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 | Nov 2 | Mar 21 | Nov 10 |
| 2024 | Apr 23 | Oct 16 | Mar 28 | Nov 23 |
| 2023 | no data | Oct 31 | no data | Oct 31 |
| 2011 | no data | Oct 21 | no data | Oct 21 |
| 2008 | Apr 30 | no data | Apr 16 | no data |
| 2007 | Apr 17 | Oct 29 | Apr 10 | Nov 2 |
| 2006 | Apr 11 | Oct 13 | Mar 27 | Oct 13 |
| 2005 | May 5 | Oct 25 | Mar 21 | Oct 26 |
| 2004 | Apr 14 | Nov 5 | Apr 1 | Nov 25 |
| 2003 | Apr 12 | Oct 27 | Mar 31 | Nov 14 |
| 2002 | Apr 6 | Oct 14 | Apr 5 | Nov 13 |
| 2001 | Apr 19 | Oct 6 | Apr 18 | Oct 17 |
| 2000 | Apr 22 | Oct 8 | Apr 9 | Oct 8 |
| 1999 | Apr 19 | Oct 5 | Apr 18 | Oct 24 |
| 1998 | Apr 12 | Oct 23 | Mar 23 | Oct 23 |
| 1997 | Apr 19 | Oct 18 | Apr 18 | Oct 28 |
| 1996 | Apr 29 | Oct 19 | Apr 29 | Oct 19 |
| 1995 | Apr 5 | Sep 23 | Apr 1 | Oct 25 |
| 1994 | no data | Oct 26 | no data | Oct 26 |
| 1981 | Apr 7 | no data | Mar 25 | no data |
| 1979 | May 5 | no data | Apr 5 | no data |
| 1978 | May 2 | Oct 7 | Mar 27 | Oct 8 |
| 1977 | Apr 5 | Oct 12 | Mar 22 | Oct 13 |
| 1976 | May 9 | Oct 10 | May 4 | Oct 18 |
| 1975 | no data | Oct 3 | no data | Oct 26 |
| 1974 | Apr 17 | Oct 3 | Apr 8 | Oct 22 |
| 1973 | Apr 14 | Oct 30 | Apr 14 | Nov 6 |
| 1972 | Apr 9 | Oct 19 | Apr 8 | Oct 19 |
| 1971 | May 3 | Nov 4 | Apr 3 | Nov 4 |
| 1970 | Apr 7 | Oct 10 | Mar 17 | Nov 16 |
| 1969 | Mar 31 | Oct 15 | Mar 31 | Oct 15 |
| 1966 | Apr 10 | no data | Apr 10 | no data |
| 1964 | Apr 9 | no data | Apr 9 | no data |
| 1963 | May 1 | Oct 29 | Mar 23 | Nov 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.