Last Frost Day

Frost history / Hereford 12 Sw, SD

Hereford 12 Sw, SD: frost dates by year

Last spring and first fall frost at NOAA station USC00393764, 1998 to 2025, measured from daily minimum temperatures.

Elevation 2,810 ft, 44.326, -103.109. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 13Oct 4
EarliestApr 20 (2025)Sep 7 (2020)
LatestMay 30 (2017)Oct 18 (2010)
Trend2.3 days earlier per decade3.1 days later per decade
Years with data2219

At 28°F (hard freeze) the median last spring date is May 2 and the median first fall date is Oct 9.

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 15Apr 30May 15May 30Jun 142000201020201999: May 82000: May 182001: Apr 252002: May 242003: May 202004: May 142005: May 152011: May 52012: May 122013: May 52014: May 152015: May 302016: May 142017: May 302018: Apr 252019: May 212020: May 112021: May 112022: May 222023: May 12024: May 42025: Apr 20

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 272000201020201998: Oct 121999: Sep 142000: Sep 232001: Oct 52004: Sep 282005: Oct 42010: Oct 182012: Oct 42013: Oct 42015: Oct 162016: Oct 72017: Oct 42018: Oct 32019: Oct 32020: Sep 72021: Oct 122023: Oct 72024: Oct 142025: Oct 13

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
2025Apr 20Oct 13Apr 8Oct 29
2024May 4Oct 14Apr 21Nov 5
2023May 1Oct 7Apr 30Oct 25
2022May 22no dataMay 22no data
2021May 11Oct 12May 4Oct 21
2020May 11Sep 7May 10Sep 8
2019May 21Oct 3May 2Oct 9
2018Apr 25Oct 3Apr 16Oct 4
2017May 30Oct 4May 1Oct 26
2016May 14Oct 7May 14Oct 7
2015May 30Oct 16May 1Oct 17
2014May 15no dataMay 15no data
2013May 5Oct 4May 4Oct 6
2012May 12Oct 4Apr 10Oct 5
2011May 5no dataMay 2no data
2010no dataOct 18no dataOct 29
2005May 15Oct 4May 3Oct 6
2004May 14Sep 28May 2Oct 16
2003May 20no dataMay 20no data
2002May 24no dataMay 24no data
2001Apr 25Oct 5Apr 25Oct 5
2000May 18Sep 23Apr 20Sep 24
1999May 8Sep 14Apr 17Oct 6
1998no dataOct 12no dataNov 4

"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.