ST HELENS RFD, OREGON

Period of Record General Climate Summary - Heating Degree Days

Station:(357466) ST HELENS RFD
From Year=1976 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	789	629	537	394	253	107	32	21	88	322	596	788	4555
60	634	487	382	253	134	34	4	2	26	182	446	633	3216
57	541	403	290	177	78	12	1	0	8	113	356	540	2520
55	479	347	232	132	50	5	0	0	2	76	298	478	2100
50	325	212	109	47	10	0	0	0	0	20	165	325	1213

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