Last Frost Day

Frost history / Danbury, CT

Danbury, CT: frost dates by year

Last spring and first fall frost at NOAA station USC00061762, 1951 to 2024, measured from daily minimum temperatures.

Elevation 405 ft, 41.400, -73.421. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianApr 25Oct 11
EarliestApr 4 (2021)Sep 20 (1979)
LatestMay 28 (1994)Nov 5 (1971)
Trend1.8 days earlier per decade3.0 days later per decade
Years with data5558

At 28°F (hard freeze) the median last spring date is Apr 12 and the median first fall date is Oct 23.

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 30Jun 1419601970198019902000201020201951: Apr 241952: May 31953: Apr 221954: Apr 131955: May 101956: May 251957: Apr 161958: Apr 111959: Apr 241960: May 21961: May 11962: Apr 211963: May 241964: May 31965: Apr 251966: May 111967: May 131968: Apr 291969: Apr 211970: May 71971: Apr 251972: May 111973: Apr 151974: May 81975: Apr 231976: May 131977: May 91978: May 51979: Apr 211980: Apr 191981: May 91982: Apr 151983: May 181984: May 181985: May 91992: Apr 151993: Apr 281994: May 281995: Apr 251996: May 151997: Apr 221998: Apr 292000: Apr 142001: Apr 272002: May 212003: Apr 182004: Apr 102005: Apr 172007: Apr 112011: Apr 222016: Apr 152017: Apr 92019: Apr 292021: Apr 42022: Apr 18

First fall frost (32°F)

Sep 12Sep 27Oct 12Oct 27Nov 1119601970198019902000201020201951: Sep 301952: Oct 41953: Sep 241954: Oct 81955: Oct 231956: Sep 211957: Sep 281958: Oct 61959: Oct 161960: Oct 21961: Oct 51962: Sep 211963: Sep 241964: Oct 61965: Sep 281966: Oct 71967: Oct 231968: Oct 61969: Oct 161970: Oct 171971: Nov 51972: Oct 21973: Oct 191974: Sep 241975: Oct 31976: Oct 111977: Oct 111978: Oct 91979: Sep 201980: Oct 101981: Oct 101982: Oct 111983: Oct 211984: Oct 61985: Oct 121991: Oct 141992: Oct 11993: Oct 11994: Oct 61995: Oct 181996: Oct 41997: Sep 252000: Oct 232001: Oct 92002: Oct 152003: Oct 202004: Nov 42005: Nov 32006: Oct 142007: Oct 292009: Oct 122016: Oct 152017: Nov 12018: Oct 192020: Oct 182022: Oct 192023: Nov 22024: Oct 28

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
2024no dataOct 28no dataOct 29
2023no dataNov 2no dataNov 2
2022Apr 18Oct 19Mar 30Oct 30
2021Apr 4no dataApr 3no data
2020no dataOct 18no dataOct 31
2019Apr 29no dataApr 2no data
2018no dataOct 19no dataNov 11
2017Apr 9Nov 1Mar 24Nov 10
2016Apr 15Oct 15Apr 9Nov 1
2011Apr 22no dataApr 9no data
2009no dataOct 12no dataNov 7
2007Apr 11Oct 29Apr 11Nov 8
2006no dataOct 14no dataOct 27
2005Apr 17Nov 3Apr 16Nov 11
2004Apr 10Nov 4Apr 5Nov 9
2003Apr 18Oct 20Apr 1Oct 25
2002May 21Oct 15Apr 7Oct 24
2001Apr 27Oct 9Apr 19Oct 29
2000Apr 14Oct 23Apr 14Nov 19
1998Apr 29no dataApr 13no data
1997Apr 22Sep 25Apr 10Oct 2
1996May 15Oct 4May 14Oct 4
1995Apr 25Oct 18Apr 17Nov 6
1994May 28Oct 6Apr 23Oct 12
1993Apr 28Oct 1Apr 8Oct 11
1992Apr 15Oct 1Apr 13Oct 18
1991no dataOct 14no dataOct 21
1985May 9Oct 12Apr 12Oct 29
1984May 18Oct 6Apr 10Oct 6
1983May 18Oct 21Mar 31Oct 21
1982Apr 15Oct 11Apr 15Oct 18
1981May 9Oct 10Apr 22Oct 11
1980Apr 19Oct 10Apr 17Oct 10
1979Apr 21Sep 20Apr 8Oct 27
1978May 5Oct 9Apr 10Oct 9
1977May 9Oct 11Apr 10Oct 24
1976May 13Oct 11Apr 13Oct 12
1975Apr 23Oct 3Apr 22Oct 31
1974May 8Sep 24May 5Oct 19
1973Apr 15Oct 19Apr 15Nov 7
1972May 11Oct 2Apr 28Oct 11
1971Apr 25Nov 5Apr 15Nov 8
1970May 7Oct 17Apr 12Oct 20
1969Apr 21Oct 16Apr 13Oct 23
1968Apr 29Oct 6Apr 6Oct 31
1967May 13Oct 23Apr 13Oct 29
1966May 11Oct 7Apr 12Oct 27
1965Apr 25Sep 28Apr 5Oct 6
1964May 3Oct 6Apr 10Oct 8
1963May 24Sep 24Apr 26Sep 24
1962Apr 21Sep 21Apr 18Oct 25
1961May 1Oct 5Apr 4Oct 28
1960May 2Oct 2Apr 11Oct 22
1959Apr 24Oct 16Apr 14Oct 20
1958Apr 11Oct 6Apr 10Oct 6
1957Apr 16Sep 28Apr 16Sep 29
1956May 25Sep 21May 9Oct 11
1955May 10Oct 23Apr 9Oct 23
1954Apr 13Oct 8Apr 10Oct 8
1953Apr 22Sep 24Mar 20Oct 8
1952May 3Oct 4Apr 12Oct 20
1951Apr 24Sep 30Mar 27Sep 30

"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.