Last Frost Day

Frost history / Britt 3E, IA

Britt 3E, IA: frost dates by year

Last spring and first fall frost at NOAA station USC00130923, 1951 to 2019, measured from daily minimum temperatures.

Elevation 1,220 ft, 43.106, -93.744. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 2Oct 4
EarliestApr 9 (2006)Sep 15 (2007)
LatestMay 23 (1963)Oct 28 (1963)
Trend1.9 days earlier per decadelittle change (less than half a day per decade)
Years with data5254

At 28°F (hard freeze) the median last spring date is Apr 17 and the median first fall date is Oct 14.

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 301960197019801990200020101951: May 111952: Apr 241953: May 131954: May 81955: May 81956: May 161957: May 51958: Apr 291959: Apr 221960: May 111961: May 31962: Apr 201963: May 231964: Apr 101965: Apr 281967: May 121968: May 171969: May 121970: May 21971: May 121972: May 51975: Apr 221977: Apr 291978: May 21980: May 71985: Apr 151986: Apr 221988: Apr 271989: May 71990: May 11991: May 71992: May 61993: Apr 211994: May 21995: Apr 281996: May 11997: May 151998: Apr 181999: Apr 192000: Apr 212001: Apr 242002: May 32003: Apr 112004: May 42005: May 42006: Apr 92007: Apr 152008: Apr 302009: Apr 212010: May 92011: May 42015: Apr 23

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 111960197019801990200020101951: Sep 251952: Oct 41953: Sep 221954: Sep 221955: Oct 151956: Sep 301957: Oct 101958: Oct 11959: Oct 91960: Oct 161961: Sep 281962: Oct 231963: Oct 281964: Oct 51965: Sep 261966: Oct 11967: Sep 281968: Oct 41969: Oct 141970: Oct 101971: Oct 101972: Sep 301973: Oct 161974: Sep 221975: Oct 21976: Oct 61979: Oct 51980: Oct 121984: Sep 261985: Oct 11986: Oct 61988: Oct 41989: Sep 231990: Oct 101991: Sep 191992: Sep 291993: Sep 271996: Oct 31997: Oct 141998: Oct 81999: Oct 22000: Sep 252001: Oct 62002: Sep 242003: Sep 302004: Oct 22005: Oct 82006: Oct 122007: Sep 152008: Oct 162010: Oct 32014: Oct 42015: Oct 162019: Oct 11

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
2019no dataOct 11no dataOct 14
2015Apr 23Oct 16Apr 23Oct 17
2014no dataOct 4no dataOct 31
2011May 4no dataMay 4no data
2010May 9Oct 3Apr 9Oct 29
2009Apr 21no dataApr 11no data
2008Apr 30Oct 16Apr 29Oct 28
2007Apr 15Sep 15Apr 14Nov 3
2006Apr 9Oct 12Apr 9Oct 12
2005May 4Oct 8May 4Oct 22
2004May 4Oct 2Apr 14Oct 17
2003Apr 11Sep 30Apr 11Oct 1
2002May 3Sep 24Apr 28Oct 13
2001Apr 24Oct 6Apr 18Oct 6
2000Apr 21Sep 25Apr 13Oct 6
1999Apr 19Oct 2Apr 18Oct 4
1998Apr 18Oct 8Mar 25Nov 3
1997May 15Oct 14Apr 18Oct 21
1996May 1Oct 3Apr 30Oct 28
1995Apr 28no dataApr 11no data
1994May 2no dataApr 8no data
1993Apr 21Sep 27Apr 10Oct 2
1992May 6Sep 29Apr 13Oct 17
1991May 7Sep 19Apr 10Oct 7
1990May 1Oct 10May 1Oct 10
1989May 7Sep 23May 6Oct 3
1988Apr 27Oct 4Apr 19Oct 5
1986Apr 22Oct 6Apr 22Oct 6
1985Apr 15Oct 1Apr 9Nov 2
1984no dataSep 26no dataSep 26
1980May 7Oct 12May 7Oct 12
1979no dataOct 5no dataOct 12
1978May 2no dataMay 2no data
1977Apr 29no dataApr 6no data
1976no dataOct 6no dataOct 6
1975Apr 22Oct 2Apr 11Oct 29
1974no dataSep 22no dataSep 22
1973no dataOct 16no dataNov 4
1972May 5Sep 30Apr 8Oct 15
1971May 12Oct 10Apr 14Oct 31
1970May 2Oct 10Apr 10Nov 14
1969May 12Oct 14Apr 6Oct 14
1968May 17Oct 4May 5Oct 25
1967May 12Sep 28May 6Oct 11
1966no dataOct 1no dataOct 19
1965Apr 28Sep 26Apr 28Oct 22
1964Apr 10Oct 5Apr 9Oct 9
1963May 23Oct 28May 22Oct 29
1962Apr 20Oct 23Apr 16Oct 24
1961May 3Sep 28May 2Sep 28
1960May 11Oct 16May 8Oct 19
1959Apr 22Oct 9Apr 13Oct 12
1958Apr 29Oct 1Apr 29Oct 1
1957May 5Oct 10Apr 14Oct 10
1956May 16Sep 30Apr 30Oct 9
1955May 8Oct 15Apr 7Oct 15
1954May 8Sep 22May 7Oct 18
1953May 13Sep 22Apr 20Oct 27
1952Apr 24Oct 4Apr 11Oct 5
1951May 11Sep 25Apr 26Sep 25

"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.