Last Frost Day

Frost history / Snowflake, AZ

Snowflake, AZ: frost dates by year

Last spring and first fall frost at NOAA station USC00028012, 1951 to 2015, measured from daily minimum temperatures.

Elevation 5,642 ft, 34.508, -110.084. Download the data (JSON) · NOAA daily records

Summary at 32°F

Last spring frostFirst fall frost
MedianMay 14Oct 8
EarliestApr 19 (1990)Sep 4 (1961)
LatestJun 23 (2002)Oct 31 (1988)
Trend2.3 days earlier per decade2.2 days later per decade
Years with data6263

At 28°F (hard freeze) the median last spring date is May 3 and the median first fall date is Oct 17.

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 30Jun 14Jun 291960197019801990200020101951: Jun 81952: May 231953: Jun 41954: May 21955: Jun 21956: May 161957: May 131958: May 151959: May 111960: May 261961: May 161962: Jun 161963: May 131965: May 271966: Apr 281968: Jun 101969: May 71970: May 31971: Jun 11972: May 261973: May 41974: May 211975: May 221976: May 91977: May 191978: May 181979: May 121980: Jun 21981: May 211982: May 131983: May 181984: May 81985: May 151986: May 171987: May 271988: May 81989: Apr 281990: Apr 191991: May 121992: Apr 231993: Jun 61994: May 211995: Jun 91996: Apr 301997: May 21998: May 161999: May 182000: May 132001: May 42002: Jun 232003: May 122004: May 12005: Apr 222006: Apr 252007: May 72008: May 42009: Apr 302010: May 112012: May 272013: May 32014: May 212015: May 10

First fall frost (32°F)

Aug 28Sep 12Sep 27Oct 12Oct 27Nov 111960197019801990200020101951: Oct 61952: Sep 131953: Sep 291954: Oct 151955: Sep 211956: Oct 101957: Sep 191958: Oct 221959: Oct 41960: Sep 241961: Sep 41962: Oct 71963: Oct 141964: Oct 201967: Oct 71968: Sep 171969: Oct 21970: Sep 231971: Sep 191972: Oct 221973: Sep 261974: Sep 281975: Oct 141976: Oct 81977: Oct 121978: Sep 201979: Oct 171980: Oct 161981: Oct 161982: Oct 21983: Oct 221984: Oct 161985: Oct 151986: Oct 41987: Oct 31988: Oct 311989: Oct 181990: Oct 91991: Oct 261992: Oct 71993: Oct 191994: Oct 81995: Oct 51996: Oct 211997: Oct 121998: Oct 61999: Oct 172000: Sep 252001: Oct 112002: Oct 42003: Oct 252004: Oct 232005: Sep 142006: Oct 192007: Oct 72008: Oct 122009: Sep 232010: Oct 242011: Oct 82012: Oct 132013: Sep 282014: Oct 132015: Oct 30

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
2015May 10Oct 30Apr 17Oct 30
2014May 21Oct 13May 21Nov 3
2013May 3Sep 28May 3Sep 28
2012May 27Oct 13May 27Oct 25
2011no dataOct 8no dataOct 8
2010May 11Oct 24May 11Oct 28
2009Apr 30Sep 23Apr 30Oct 2
2008May 4Oct 12May 3Oct 12
2007May 7Oct 7May 6Oct 7
2006Apr 25Oct 19Apr 19Oct 19
2005Apr 22Sep 14Apr 21Oct 31
2004May 1Oct 23Apr 12Oct 23
2003May 12Oct 25May 10Oct 26
2002Jun 23Oct 4Apr 22Oct 28
2001May 4Oct 11Apr 15Nov 19
2000May 13Sep 25May 13Nov 1
1999May 18Oct 17Apr 30Oct 17
1998May 16Oct 6May 15Oct 6
1997May 2Oct 12Apr 26Oct 13
1996Apr 30Oct 21Apr 23Oct 22
1995Jun 9Oct 5May 8Oct 6
1994May 21Oct 8Apr 12Oct 17
1993Jun 6Oct 19Apr 20Oct 21
1992Apr 23Oct 7Apr 20Oct 8
1991May 12Oct 26May 5Oct 29
1990Apr 19Oct 9Apr 10Oct 10
1989Apr 28Oct 18Apr 26Oct 18
1988May 8Oct 31May 7Nov 12
1987May 27Oct 3Apr 20Oct 3
1986May 17Oct 4Apr 27Oct 13
1985May 15Oct 15May 14Nov 2
1984May 8Oct 16May 8Oct 16
1983May 18Oct 22May 17Nov 9
1982May 13Oct 2Apr 16Oct 9
1981May 21Oct 16Apr 11Oct 17
1980Jun 2Oct 16Jun 1Oct 17
1979May 12Oct 17May 11Oct 22
1978May 18Sep 20May 6Oct 26
1977May 19Oct 12May 19Nov 2
1976May 9Oct 8Apr 27Oct 8
1975May 22Oct 14May 22Oct 14
1974May 21Sep 28May 21Oct 31
1973May 4Sep 26May 2Oct 11
1972May 26Oct 22May 2Oct 30
1971Jun 1Sep 19May 23Oct 20
1970May 3Sep 23May 3Oct 9
1969May 7Oct 2May 4Oct 5
1968Jun 10Sep 17Jun 9Sep 17
1967no dataOct 7no dataOct 7
1966Apr 28no dataApr 24no data
1965May 27no dataMay 9no data
1964no dataOct 20no dataOct 31
1963May 13Oct 14Apr 28Nov 1
1962Jun 16Oct 7May 22Oct 13
1961May 16Sep 4May 8Oct 3
1960May 26Sep 24May 20Oct 30
1959May 11Oct 4Apr 22Oct 4
1958May 15Oct 22Apr 27Oct 22
1957May 13Sep 19Apr 28Oct 23
1956May 16Oct 10May 15Oct 20
1955Jun 2Sep 21May 16Oct 7
1954May 2Oct 15Apr 27Oct 15
1953Jun 4Sep 29May 30Oct 21
1952May 23Sep 13Apr 29Oct 15
1951Jun 8Oct 6May 3Oct 14

"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 1991–2020 frost probabilities.