FT DEFIANCE, ARIZONA

Period of Record General Climate Summary - Heating Degree Days

Station:(023102) FORT DEFIANCE
From Year=1897 To Year=1949
Heating Degree Days for Selected Base Temperature (F)
Base	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Annual
65	1236	972	850	575	376	111	13	14	177	515	839	1181	6857
60	1081	831	695	425	230	39	1	1	77	362	689	1026	5457
57	988	746	602	337	154	17	0	0	43	275	599	933	4693
55	926	690	540	280	112	9	0	0	28	220	539	871	4214
50	771	549	386	154	45	1	0	0	8	106	390	716	3124

Heating Degree Day units are computed as the difference between the base temperature and the daily average temperature. (Base Temp. - Daily Ave. Temp.) One unit is accumulated for each degree Fahrenheit the average temperature is below the base temperature. Negative numbers are discarded. Example: If the days high temperature was 65 and the low temperature was 31, the base 50 heating degree day units is 50 - ((65 + 31) / 2) = 2. This is done for each day of the month and summed.
Table updated on Oct 31, 2012
Months with 5 or more missing days are not considered
Years with 1 or more missing months are not considered

Western Regional Climate Center, wrcc@dri.edu