Last Frost Day

Frost history / Ester, AK

Ester, AK: frost dates by year

Last spring and first fall frost at NOAA station USC00502870, 2007 to 2021, measured from daily minimum temperatures.

Elevation 655 ft, 64.846, -148.026. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 22Aug 30
EarliestMay 10 (2016)Aug 12 (2009)
LatestJun 15 (2018)Sep 6 (2020)
Trend3.8 days later per decade8.9 days later per decade
Years with data1212

At 28°F (hard freeze) the median last spring date is May 16 and the median first fall date is Sep 11.

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)

Apr 30May 15May 30Jun 14Jun 29201020202007: May 182008: May 312009: May 192010: May 172014: Jun 122015: Jun 132016: May 102017: Jun 142018: Jun 152019: May 142020: May 202021: May 24

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12201020202008: Aug 252009: Aug 122010: Aug 272011: Sep 22012: Aug 222014: Aug 302015: Aug 312016: Sep 32017: Sep 32018: Sep 12019: Aug 202020: Sep 6

Dots are single years. The gray line is the median, the green line the fitted trend.

Year by year

YearLast spring 32°FFirst fall 32°FLast spring 28°FFirst fall 28°F
2021May 24no dataMay 2no data
2020May 20Sep 6May 18Sep 13
2019May 14Aug 20May 7Sep 18
2018Jun 15Sep 1May 17Sep 9
2017Jun 14Sep 3May 8Sep 30
2016May 10Sep 3May 5Sep 8
2015Jun 13Aug 31May 7Sep 2
2014Jun 12Aug 30May 21Aug 30
2012no dataAug 22no dataSep 8
2011no dataSep 2no dataSep 25
2010May 17Aug 27May 14Sep 19
2009May 19Aug 12May 17Aug 20
2008May 31Aug 25May 31Sep 21
2007May 18no dataMay 18no data

"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.