OLYMPIA AP, WASHINGTON

Period of Record General Climate Summary - Heating Degree Days

Station:(456114) OLYMPIA WSO AP
From Year=1948 To Year=2012
Heating Degree Days for Selected Base Temperature (F)
Base	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Annual
65	832	685	666	520	356	200	91	87	202	462	661	817	5579
60	677	544	511	371	212	82	18	15	84	308	511	662	3995
57	584	459	418	283	137	34	3	3	37	220	421	569	3169
55	522	403	357	227	94	16	1	1	19	166	361	507	2673
50	368	264	207	103	22	1	0	0	2	62	220	353	1603

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