Last Frost Day

Frost history / Hat Creek, CA

Hat Creek, CA: frost dates by year

Last spring and first fall frost at NOAA station USC00043824, 1951 to 2024, measured from daily minimum temperatures.

Elevation 3,015 ft, 40.932, -121.543. Download the data (JSON), NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 29Sep 21
EarliestApr 25 (1987)Aug 24 (1966)
LatestJul 17 (1999)Oct 21 (1991)
Trend1.1 days earlier per decade0.5 days later per decade
Years with data5457

At 28°F (hard freeze) the median last spring date is May 6 and the median first fall date is Oct 9.

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 29Jul 14Jul 2919601970198019902000201020201951: Jun 31953: Jun 101962: Jun 51963: Jun 291964: May 221965: Jun 11966: Jul 21967: May 141968: Jun 301969: May 201970: May 141971: May 181972: Jun 111973: Jun 181974: May 221975: Jun 251976: Jun 51977: May 281978: May 161979: May 301980: May 261981: May 71983: May 161984: May 161985: May 131987: Apr 251989: May 261991: May 311992: Jun 131993: May 81994: May 11998: May 181999: Jul 172000: Jun 12001: Jun 42002: Jun 92003: May 192004: May 152005: Jun 72006: May 302007: Jun 262008: Jun 212009: May 132011: Jun 32012: Jun 62014: May 122015: May 162016: Apr 272017: May 182018: Jun 102019: May 32022: Jun 142023: Jun 222024: May 23

First fall frost (32°F)

Aug 13Aug 28Sep 12Sep 27Oct 12Oct 2719601970198019902000201020201951: Oct 41952: Oct 121962: Sep 191963: Oct 71964: Sep 21966: Aug 241967: Sep 131968: Sep 201969: Sep 151970: Sep 51971: Sep 191972: Sep 111973: Sep 21974: Sep 131975: Oct 141976: Oct 31977: Sep 221978: Sep 181979: Oct 201980: Oct 111981: Sep 231982: Sep 11983: Oct 141984: Sep 231985: Sep 111986: Sep 211987: Sep 161988: Sep 181990: Oct 71991: Oct 211992: Sep 71993: Sep 211997: Sep 191998: Oct 41999: Aug 312000: Sep 232001: Oct 92002: Sep 82003: Sep 142004: Sep 212005: Sep 102006: Sep 172007: Sep 242008: Sep 232009: Sep 92011: Oct 122014: Oct 22015: Sep 52016: Sep 152017: Sep 222018: Sep 142019: Oct 22020: Oct 52021: Sep 292022: Oct 102023: Sep 22024: Oct 18

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
2024May 23Oct 18May 2Oct 18
2023Jun 22Sep 2May 1Oct 12
2022Jun 14Oct 10May 10Oct 14
2021no dataSep 29no dataOct 10
2020no dataOct 5no dataOct 9
2019May 3Oct 2May 1Oct 2
2018Jun 10Sep 14Apr 20Sep 16
2017May 18Sep 22Apr 30Sep 22
2016Apr 27Sep 15Apr 26Oct 5
2015May 16Sep 5Apr 17Oct 23
2014May 12Oct 2May 11Oct 27
2012Jun 6no dataMay 18no data
2011Jun 3Oct 12Jun 3Oct 25
2009May 13Sep 9Apr 27Sep 30
2008Jun 21Sep 23May 5Sep 23
2007Jun 26Sep 24May 5Sep 24
2006May 30Sep 17Apr 22Sep 17
2005Jun 7Sep 10Apr 19Sep 14
2004May 15Sep 21Apr 22Sep 21
2003May 19Sep 14May 19Oct 10
2002Jun 9Sep 8May 11Sep 8
2001Jun 4Oct 9May 4Oct 9
2000Jun 1Sep 23May 12Sep 23
1999Jul 17Aug 31May 16Oct 16
1998May 18Oct 4Apr 25Oct 10
1997no dataSep 19no dataOct 5
1994May 1no dataApr 28no data
1993May 8Sep 21May 4Sep 21
1992Jun 13Sep 7Apr 23Oct 5
1991May 31Oct 21Apr 27Oct 23
1990no dataOct 7no dataOct 7
1989May 26no dataMay 19no data
1988no dataSep 18no dataOct 30
1987Apr 25Sep 16Apr 20Oct 14
1986no dataSep 21no dataOct 12
1985May 13Sep 11Apr 26Oct 9
1984May 16Sep 23May 16Oct 15
1983May 16Oct 14May 10Oct 15
1982no dataSep 1no dataOct 1
1981May 7Sep 23May 6Oct 12
1980May 26Oct 11May 24Oct 17
1979May 30Oct 20Apr 25Oct 20
1978May 16Sep 18Apr 21Oct 22
1977May 28Sep 22May 6Oct 22
1976Jun 5Oct 3May 20Oct 17
1975Jun 25Oct 14May 25Oct 14
1974May 22Sep 13May 19Sep 28
1973Jun 18Sep 2Apr 30Oct 3
1972Jun 11Sep 11May 9Sep 13
1971May 18Sep 19May 17Sep 19
1970May 14Sep 5May 12Sep 14
1969May 20Sep 15Apr 27Oct 3
1968Jun 30Sep 20May 15Sep 20
1967May 14Sep 13May 13Oct 6
1966Jul 2Aug 24Jun 4Oct 13
1965Jun 1no dataMay 7no data
1964May 22Sep 2May 16Oct 14
1963Jun 29Oct 7Apr 24Oct 27
1962Jun 5Sep 19Jun 4Oct 5
1953Jun 10no dataMay 12no data
1952no dataOct 12no dataOct 25
1951Jun 3Oct 4May 14Oct 5

"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.