Last Frost Day

Frost history / Green Bay Wfo, WI

Green Bay Wfo, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00473268, 2004 to 2025, measured from daily minimum temperatures.

Elevation 682 ft, 44.498, -88.112. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 4Oct 14
EarliestApr 16 (2007)Oct 2 (2011)
LatestMay 28 (2008)Oct 29 (2023)
Trend5.3 days earlier per decade7.2 days later per decade
Years with data1920

At 28°F (hard freeze) the median last spring date is Apr 27 and the median first fall date is Oct 27.

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)

Mar 31Apr 15Apr 30May 15May 30Jun 14201020202004: May 52005: May 112006: May 222007: Apr 162008: May 282009: Apr 232010: May 102011: May 42012: Apr 292016: May 152017: May 82018: Apr 292019: Apr 282020: May 132021: May 122022: Apr 282023: May 12024: Apr 252025: Apr 16

First fall frost (32°F)

Sep 27Oct 12Oct 27Nov 11201020202004: Oct 42005: Oct 202006: Oct 112007: Oct 122008: Oct 32009: Oct 102010: Oct 42011: Oct 22012: Oct 72015: Oct 162016: Oct 142017: Oct 262018: Oct 122019: Oct 142020: Oct 152021: Oct 242022: Oct 142023: Oct 292024: Oct 162025: Oct 24

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 16Oct 24Apr 8Nov 2
2024Apr 25Oct 16Apr 25Nov 26
2023May 1Oct 29Apr 24Oct 30
2022Apr 28Oct 14Apr 27Oct 27
2021May 12Oct 24Apr 22Nov 2
2020May 13Oct 15May 12Oct 17
2019Apr 28Oct 14Apr 28Oct 25
2018Apr 29Oct 12Apr 29Oct 12
2017May 8Oct 26May 8Oct 29
2016May 15Oct 14Apr 12Nov 11
2015no dataOct 16no dataOct 18
2012Apr 29Oct 7Apr 27Oct 12
2011May 4Oct 2May 4Oct 29
2010May 10Oct 4Apr 9Oct 22
2009Apr 23Oct 10Apr 15Oct 10
2008May 28Oct 3Apr 29Oct 29
2007Apr 16Oct 12Apr 15Oct 28
2006May 22Oct 11Apr 8Oct 12
2005May 11Oct 20Apr 30Oct 28
2004May 5Oct 4May 3Oct 5

"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.