NEWHALEM, WASHINGTON

Period of Record General Climate Summary - Heating Degree Days

Station:(457690) SKAGIT POWER PLANT
From Year=1909 To Year=1958
Heating Degree Days for Selected Base Temperature (F)
Base Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual
65 987 784 708 458 265 152 60 63 170 431 704 878 5660
60 832 643 553 313 141 57 13 13 75 281 554 723 4198
57 739 558 461 232 83 24 4 3 37 198 464 630 3433
55 677 502 400 181 54 11 2 1 20 148 404 568 2968
50 522 361 253 79 11 1 0 0 2 56 257 413 1957
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