PORTLAND RFC CITY, OREGON

Period of Record General Climate Summary - Growing Degree Days

Station:(356761) PORTLAND WSO CITY
From Year=1928 To Year=1973
Growing Degree Days for Selected Base Temperature (F)
Base Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual
40 M 96 151 252 387 587 706 887 883 729 505 230 126 5538
40 S 96 246 498 885 1472 2178 3065 3948 4677 5182 5412 5538 5538
45 M 32 56 119 240 432 556 732 728 579 352 108 43 3976
45 S 32 88 207 446 878 1434 2166 2894 3473 3825 3933 3976 3976
50 M 5 12 39 117 279 406 577 573 429 206 32 7 2682
50 S 5 17 56 173 451 858 1435 2008 2437 2642 2674 2682 2682
55 M 0 1 9 43 148 257 422 418 281 91 4 1 1677
55 S 0 2 10 54 202 460 882 1300 1581 1672 1676 1677 1677
60 M 0 0 1 12 65 128 268 264 148 28 0 0 914
60 S 0 0 1 14 78 206 474 738 886 914 914 914 914
Corn Growing Degree Days
50 M 17 40 92 178 309 404 561 559 429 238 64 22 2914
50 S 17 57 150 328 636 1041 1601 2160 2590 2828 2892 2914 2914
M = Monthly Data
S - Running sum of monthly data.
Growing Degree Day units are computed as the difference between the daily average temperature and the base temperature. (Daily Ave. Temp. - Base Temp.) One unit is accumulated for each degree Fahrenheit the average temperature is above the base temperature. Negative numbers are discarded. Example: If the days high temperature was 95 and the low temperature was 51, the base 60 heating degree day units is ((95 + 51) / 2) - 60 = 13. This is done for each day of the month and summed.
Corn Growing Degree Day units have the limitations that the maximum daily temperatures greater than 86 F are set to 86 F and minimums less than 50 F are set to 50 F.
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