Frost history / Hidden Falls Hatchery, AK

Hidden Falls Hatchery, AK: frost dates by year

Last spring and first fall frost at NOAA station USC00503605, 1993 to 2025, measured from daily minimum temperatures.

Elevation 22 ft, 57.218, -134.877. Download the data (JSON), NOAA daily records

Summary at 32°F

	Last spring frost	First fall frost
Median	Apr 21	Oct 29
Earliest	Apr 9 (2012)	Oct 16 (2008)
Latest	May 23 (2009)	Nov 16 (2010)
Trend	2.5 days earlier per decade	4.1 days earlier per decade
Years with data	10	13

At 28°F (hard freeze) the median last spring date is Apr 3 and the median first fall date is Nov 14.

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 20	Oct 30	Mar 17	Dec 8
2024	Apr 17	Oct 20	Mar 7	Oct 21
2023	no data	Oct 22	no data	Nov 20
2014	Apr 22	Nov 12	Apr 12	Nov 14
2013	May 7	Nov 9	Mar 29	Nov 10
2012	Apr 9	Oct 21	Mar 24	Oct 27
2011	Apr 29	no data	Mar 24	no data
2010	Apr 13	Nov 16	Apr 8	Nov 17
2009	May 23	Oct 29	May 23	Nov 26
2008	May 9	Oct 16	Apr 24	Dec 2
2006	no data	Oct 22	no data	Oct 22
2005	no data	Nov 4	no data	Nov 6
2004	no data	Oct 23	no data	Oct 23
1994	Apr 19	no data	Apr 17	no data
1993	no data	Nov 16	no data	Nov 20

"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.