Chilling Hours / First and Last Frost

Chilling Hours for the 2023-2024 Season
October 1, 2023 thru February 29, 2024

Method 1
 No of Hrs >=32
&< =45 F

Method 2
No of Hrs <=45 F

Oct

 52 52

Nov

 121 136

Dec

 231 259

Jan

 241 390

Feb

 97 113

TOTAL

 742 950
(last updated 03/01/2024)

The dormant buds of many plants require a period of cold weather to grow, flower, and develop properly, but requirements vary widely by species. For dormant buds of fruit trees, this is commonly referred to as the chilling requirement. Chilling hours are calculated as a tool for fruit producers to gauge whether their crop has been exposed to cold temperatures for a long enough time period. This table shows chilling hours as recorded at the Overton Center.

To see chilling hours for other areas in the state, please visit https://texaset.tamu.edu/, select the location nearest you, then click the Chill Units button.

Temperatures can fluctuate from one location to another, however, so the number of chilling hours at your peach orchard may be different than what we have recorded here. For chilling hour data from past years, see the table below. Several methods exist for calculating chilling hours; two are presented here.
 

Calculating Chilling Hours
Method 1: Chilling hours were calculated by counting the number of hours between 32 and 45 degrees F, from October 1st through February 28th/29th.
Method 2: Chilling hours were calculated by counting the number of hours at or below 45 degrees F, from October 1st through February 28th/29th.

Historical Date of First and Last Frost and Chilling Hour Data
Season Date of First Frost Date of Last Frost  First Frost Temperature (F) Chilling Hours Method 1 Chilling Hours Method 2
2022-2023 Oct 19, 2022 Mar 20, 2023 30.16 814 1008
2021-2022 Nov 19, 2021 Mar 12, 2022 32.0 724 999
2020-2021 Dec 1, 2020 Feb 20, 2021 29.4 841 1134
2019-2020 Oct 31, 2019 Feb 27, 2020 31.8 929 1081
2018-2019 Nov 13, 2018 Apr 1, 2019 31.3 1,040 1,238
2017-2018 Oct 28, 2017 Feb 12, 2018 30.9 811 1,115
2016-2017 Nov 20, 2016 Mar 14, 2017 31.8 394 509
2015-2016 Nov 22, 2015 Mar 21, 2016 31.7 710 798
2014-2015 Nov 13, 2014 Mar 7, 2015 31.9 1120 1346
2013-2014  Nov 13, 2013 Apr 15, 2014 30.9 1018 1404
2012-2013 Nov 13, 2012 Mar 27, 2013 31.8 801 1003
2011-2012 Nov 28, 2011 Feb 25, 2012 30.4 867 980
2010-2011 Nov 6, 2010 Mar 6, 2011 31.9 819 832
2009-2010 Dec 4, 2009 Mar 21, 2010 25.6 1067 1440
2008-2009 Oct 28, 2008 Mar 2, 2009 30.9 789 992
2007-2008 Nov 23, 2007 Mar 9, 2008 31.6 974 1156
2006-2007 Nov 3, 2006 Mar 5, 2007 30.6 907 1218
2005-2006 Nov 17, 2005 Mar 24, 2006 27.0 818 993
2004-2005 Nov 30, 2004 Mar 17, 2005 31.1 726 909
2003-2004 Nov 24, 2003 Feb 16, 2004 31.4 845 1046
2002-2003 Nov 28, 2002 Mar 10, 2003 28.5 1060 1227
2001-2002 Nov 21, 2001 Mar 10, 2002 30.1 855 1045
2000-2001 Nov 10, 2000 Feb 10, 2001 30.4 1178 1491
1999-2000 Nov 5, 1999 31.8 563 728
1998-1999 Nov 2, 1998 29.7 574 687
1997-1998 Nov 15, 1997 26.6 – –
1996-1997 Nov 27, 1996 30.2 849