PORTOLA, CALIFORNIA

Period of Record General Climate Summary - Heating Degree Days

Station:(047085) PORTOLA
From Year=1948 To Year=2006
Heating Degree Days for Selected Base Temperature (F)
Base	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Annual
65	1089	894	845	656	456	239	87	116	252	514	802	1038	6987
60	934	752	690	506	307	122	24	35	127	360	652	883	5392
57	841	668	597	416	227	72	9	12	74	272	562	790	4538
55	779	611	535	357	179	47	4	5	49	217	502	728	4013
50	624	470	380	218	85	14	0	0	14	104	353	573	2836

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 Jul 28, 2006
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