Frost history / Riverside 7 Ssw, OR
Riverside 7 Ssw, OR: frost dates by year
Last spring and first fall frost at NOAA station USC00357208, 1967 to 2001, measured from daily minimum temperatures.
Elevation 3,380 ft, 43.451, -118.224. Download the data (JSON), NOAA daily records
Summary at 32°F
| Last spring frost | First fall frost | |
|---|---|---|
| Median | Jun 1 | Sep 17 |
| Earliest | May 5 (1969) | Aug 6 (1996) |
| Latest | Jul 25 (1993) | Oct 8 (1975) |
| Trend | 8.3 days later per decade | 9.3 days earlier per decade |
| Years with data | 32 | 30 |
At 28°F (hard freeze) the median last spring date is May 16 and the median first fall date is Sep 23.
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 |
|---|---|---|---|---|
| 2001 | no data | Sep 9 | no data | Sep 9 |
| 1999 | Jun 10 | no data | May 16 | no data |
| 1998 | Jun 27 | no data | May 21 | no data |
| 1997 | Jun 24 | Sep 19 | Jun 21 | Sep 19 |
| 1996 | Jun 19 | Aug 6 | Jun 19 | Sep 6 |
| 1995 | May 28 | Aug 9 | May 27 | Aug 14 |
| 1994 | Jun 16 | Sep 5 | Jun 8 | Oct 7 |
| 1993 | Jul 25 | Aug 25 | May 9 | Sep 13 |
| 1992 | no data | Aug 24 | no data | Aug 24 |
| 1991 | May 27 | no data | Apr 30 | no data |
| 1990 | May 25 | Oct 6 | May 9 | Oct 6 |
| 1989 | May 30 | Sep 10 | May 20 | Oct 6 |
| 1988 | May 20 | Sep 12 | May 2 | Sep 18 |
| 1987 | May 21 | Sep 16 | May 20 | Sep 17 |
| 1986 | Jul 5 | Sep 21 | May 22 | Sep 23 |
| 1985 | May 13 | Sep 10 | May 13 | Sep 23 |
| 1984 | Jun 1 | no data | Jun 1 | no data |
| 1983 | Jun 13 | Sep 9 | May 14 | Sep 20 |
| 1982 | Jun 9 | Sep 11 | May 5 | Oct 2 |
| 1981 | Jul 8 | Sep 24 | May 13 | Sep 30 |
| 1980 | Jun 4 | Sep 22 | Apr 30 | Oct 17 |
| 1979 | Jun 8 | Oct 3 | May 29 | Oct 4 |
| 1978 | May 31 | Sep 19 | May 26 | Sep 19 |
| 1977 | May 28 | Sep 22 | May 15 | Sep 22 |
| 1976 | Jun 26 | Oct 4 | Jun 4 | Oct 16 |
| 1975 | May 25 | Oct 8 | May 25 | Oct 24 |
| 1974 | Jun 8 | Oct 4 | May 18 | Oct 5 |
| 1973 | Jun 18 | Sep 26 | May 1 | Oct 3 |
| 1972 | May 18 | Sep 25 | May 1 | Sep 25 |
| 1971 | May 20 | Sep 15 | May 17 | Sep 18 |
| 1970 | May 15 | Sep 12 | May 14 | Sep 12 |
| 1969 | May 5 | Oct 4 | May 3 | Oct 4 |
| 1968 | May 17 | Sep 20 | May 7 | Sep 22 |
| 1967 | May 26 | Sep 13 | May 13 | Oct 6 |
"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.