Last Frost Day

Frost history / Ellsworth 15 Nne, NE

Ellsworth 15 Nne, NE: frost dates by year

Last spring and first fall frost at NOAA station USC00252647, 1963 to 2007, measured from daily minimum temperatures.

Elevation 3,970 ft, 42.265, -102.213. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 14Sep 20
EarliestApr 24 (1987)Sep 3 (1984)
LatestJun 18 (1976)Oct 23 (1994)
Trend2.0 days earlier per decade1.2 days later per decade
Years with data3839

At 28°F (hard freeze) the median last spring date is May 2 and the median first fall date is Oct 3.

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 2919701980199020001964: Jun 21965: May 101966: May 241967: May 191968: May 201969: Jun 141970: May 31971: May 191972: May 71973: May 151974: May 221975: May 261976: Jun 181977: Apr 251978: May 131979: May 111980: May 141981: May 191982: May 71983: May 311984: May 81985: Apr 271986: May 241987: Apr 241989: Jun 11991: May 61992: May 261993: May 31994: May 71995: May 181996: May 121998: Jun 31999: May 122001: May 72003: May 212004: May 142005: May 132006: May 12

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 1119701980199020001963: Sep 291964: Sep 201965: Sep 161966: Oct 11967: Sep 271968: Sep 231969: Oct 61970: Sep 131971: Sep 191972: Sep 211973: Sep 161974: Sep 121975: Sep 121976: Sep 91977: Oct 91979: Sep 141981: Oct 11983: Sep 161984: Sep 31985: Sep 201986: Oct 91988: Oct 81989: Sep 111990: Sep 231991: Sep 181993: Sep 131994: Oct 231995: Sep 201996: Sep 261997: Oct 91998: Oct 51999: Sep 132000: Sep 232002: Sep 222003: Sep 182004: Oct 142005: Oct 52006: Sep 192007: Sep 14

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