Last Frost Day

Frost history / Danbury, WI

Danbury, WI: frost dates by year

Last spring and first fall frost at NOAA station USC00471978, 1951 to 2010, measured from daily minimum temperatures.

Elevation 950 ft, 46.009, -92.374. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 24Sep 21
EarliestApr 26 (2001)Aug 5 (1957)
LatestJun 21 (1992)Oct 10 (1997)
Trend3.1 days earlier per decade3.6 days later per decade
Years with data5759

At 28°F (hard freeze) the median last spring date is May 12 and the median first fall date is Sep 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)

Apr 15Apr 30May 15May 30Jun 14Jun 291960197019801990200020101951: Jun 41952: Jun 11953: Jun 71954: Jun 51955: May 311956: Jun 21957: Jun 21958: Jun 161959: May 241960: May 121961: May 261962: May 91963: Jun 121964: Jun 41965: May 291966: May 311967: May 221968: May 171969: Jun 201970: May 171971: May 271972: Jun 101973: May 171974: May 251975: May 161976: May 241977: May 91978: May 211979: May 251981: May 191982: Jun 31983: May 261984: May 291985: Jun 31986: Jun 21987: May 121988: Jun 91989: May 121990: Jun 41991: May 31992: Jun 211993: May 161994: May 101995: May 61996: May 131997: May 211998: Apr 291999: Apr 292000: May 202001: Apr 262002: May 202004: May 152005: May 162006: May 222007: May 172008: May 272009: Jun 3

First fall frost (32°F)

Jul 29Aug 13Aug 28Sep 12Sep 27Oct 12Oct 271960197019801990200020101951: Sep 181952: Sep 161953: Sep 71954: Sep 221955: Sep 51956: Sep 41957: Aug 51958: Aug 221959: Sep 111960: Sep 291961: Sep 231962: Sep 51963: Sep 131964: Aug 141965: Sep 261966: Sep 151967: Sep 101968: Sep 291969: Sep 281970: Sep 261971: Sep 171972: Sep 221973: Sep 181974: Sep 11975: Sep 91976: Aug 291977: Oct 21978: Sep 221979: Sep 191980: Sep 171981: Sep 201982: Sep 211983: Sep 231984: Sep 261985: Sep 211986: Sep 71987: Sep 251988: Oct 31989: Sep 131990: Oct 21991: Sep 201992: Sep 191993: Sep 111994: Oct 101995: Sep 201996: Oct 31997: Oct 101998: Sep 222000: Sep 242001: Sep 242002: Sep 242003: Sep 292004: Sep 292005: Sep 292006: Sep 212007: Sep 122008: Oct 32009: Sep 302010: Sep 26

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
2010no dataSep 26no dataOct 22
2009Jun 3Sep 30Apr 28Sep 30
2008May 27Oct 3Apr 30Oct 3
2007May 17Sep 12Apr 16Sep 15
2006May 22Sep 21Apr 25Oct 10
2005May 16Sep 29May 4Oct 7
2004May 15Sep 29May 15Oct 5
2003no dataSep 29no dataSep 29
2002May 20Sep 24May 20Oct 7
2001Apr 26Sep 24Apr 24Sep 25
2000May 20Sep 24May 19Sep 24
1999Apr 29no dataApr 24no data
1998Apr 29Sep 22Apr 28Oct 2
1997May 21Oct 10May 13Oct 26
1996May 13Oct 3May 13Oct 3
1995May 6Sep 20Apr 26Sep 22
1994May 10Oct 10May 6Oct 10
1993May 16Sep 11Apr 26Oct 2
1992Jun 21Sep 19May 26Sep 29
1991May 3Sep 20May 3Sep 27
1990Jun 4Oct 2May 11Oct 9
1989May 12Sep 13May 7Sep 26
1988Jun 9Oct 3May 17Oct 5
1987May 12Sep 25May 4Oct 3
1986Jun 2Sep 7May 3Oct 6
1985Jun 3Sep 21Apr 11Sep 26
1984May 29Sep 26May 2Sep 26
1983May 26Sep 23May 17Sep 23
1982Jun 3Sep 21Apr 29Sep 21
1981May 19Sep 20May 19Sep 28
1980no dataSep 17no dataSep 26
1979May 25Sep 19May 3Oct 5
1978May 21Sep 22May 2Oct 8
1977May 9Oct 2May 7Oct 2
1976May 24Aug 29May 8Sep 21
1975May 16Sep 9May 12Oct 2
1974May 25Sep 1May 25Sep 22
1973May 17Sep 18May 17Sep 20
1972Jun 10Sep 22May 5Sep 30
1971May 27Sep 17May 21Sep 18
1970May 17Sep 26May 6Sep 28
1969Jun 20Sep 28May 12Oct 12
1968May 17Sep 29May 5Oct 4
1967May 22Sep 10May 20Sep 24
1966May 31Sep 15May 10Sep 25
1965May 29Sep 26May 29Sep 26
1964Jun 4Aug 14Jun 2Sep 15
1963Jun 12Sep 13May 23Sep 13
1962May 9Sep 5May 2Sep 20
1961May 26Sep 23May 26Sep 25
1960May 12Sep 29May 12Sep 30
1959May 24Sep 11May 16Sep 17
1958Jun 16Aug 22Jun 14Sep 27
1957Jun 2Aug 5Jun 2Sep 26
1956Jun 2Sep 4Jun 1Sep 7
1955May 31Sep 5May 17Sep 11
1954Jun 5Sep 22May 26Sep 22
1953Jun 7Sep 7May 17Sep 13
1952Jun 1Sep 16May 29Sep 24
1951Jun 4Sep 18May 13Sep 28

"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.