PORTLAND KGW TV, OREGON

Period of Record General Climate Summary - Heating Degree Days

Station:(356749) PORTLAND WB CITY
From Year=1973 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	719	579	516	379	244	107	28	21	76	299	548	728	4241
60	564	437	361	239	123	29	2	1	17	160	398	573	2905
57	471	353	271	163	67	9	0	0	5	92	310	480	2221
55	409	297	213	118	39	3	0	0	1	58	253	419	1810
50	259	167	91	35	5	0	0	0	0	12	126	269	963

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