Last Frost Day

Frost history / Danbury Muni Ap, CT

Danbury Muni Ap, CT: frost dates by year

Last spring and first fall frost at NOAA station USW00054734, 1998 to 2024, measured from daily minimum temperatures.

Elevation 457 ft, 41.371, -73.483. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 1Oct 17
EarliestApr 4 (2021)Sep 21 (2020)
LatestMay 22 (2002)Nov 3 (2021)
Trend2.0 days earlier per decade4.2 days later per decade
Years with data2627

At 28°F (hard freeze) the median last spring date is Apr 14 and the median first fall date is Oct 30.

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 16Mar 31Apr 15Apr 30May 15May 302000201020201999: May 12000: May 12001: May 82002: May 222003: Apr 202004: Apr 102005: May 132006: May 12007: May 72008: May 12009: May 192010: May 132011: May 62012: Apr 302013: May 152014: Apr 252015: Apr 262016: Apr 172017: May 42018: Apr 242019: Apr 292020: May 212021: Apr 42022: Apr 292023: May 182024: Apr 26

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 112000201020201998: Oct 221999: Oct 72000: Sep 292001: Oct 82002: Oct 142003: Oct 32004: Oct 62005: Oct 242006: Oct 132007: Oct 282008: Oct 72009: Oct 122010: Oct 172011: Oct 282012: Oct 122013: Oct 232014: Oct 202015: Oct 172016: Oct 112017: Nov 12018: Oct 182019: Oct 52020: Sep 212021: Nov 32022: Oct 212023: Nov 12024: Oct 17

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
2024Apr 26Oct 17Mar 25Nov 10
2023May 18Nov 1Apr 3Nov 2
2022Apr 29Oct 21Mar 30Nov 14
2021Apr 4Nov 3Apr 3Nov 4
2020May 21Sep 21Apr 23Oct 30
2019Apr 29Oct 5Apr 2Nov 4
2018Apr 24Oct 18Apr 21Oct 22
2017May 4Nov 1Apr 9Nov 10
2016Apr 17Oct 11Apr 9Oct 26
2015Apr 26Oct 17Apr 25Oct 18
2014Apr 25Oct 20Apr 18Nov 3
2013May 15Oct 23Apr 4Oct 26
2012Apr 30Oct 12Apr 28Oct 13
2011May 6Oct 28Apr 22Nov 2
2010May 13Oct 17Mar 28Nov 2
2009May 19Oct 12Apr 16Oct 19
2008May 1Oct 7May 1Oct 19
2007May 7Oct 28Apr 11Oct 29
2006May 1Oct 13Mar 30Oct 27
2005May 13Oct 24Apr 17Nov 3
2004Apr 10Oct 6Mar 24Nov 4
2003Apr 20Oct 3Apr 14Oct 20
2002May 22Oct 14Apr 27Oct 15
2001May 8Oct 8Apr 20Oct 9
2000May 1Sep 29Apr 14Oct 23
1999May 1Oct 7Apr 25Nov 8
1998no dataOct 22no dataNov 3

"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.