PORTLAND KGW TV, OREGON

Period of Record General Climate Summary - Growing Degree Days

Station:(356749) PORTLAND WB CITY
From Year=1973 To Year=2012
Growing Degree Days for Selected Base Temperature (F)
Base Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual
40 M 111 151 262 374 550 692 873 888 740 480 213 101 5433
40 S 111 262 523 897 1447 2140 3012 3900 4640 5120 5332 5433 5433
45 M 34 56 125 227 395 542 718 733 590 326 95 30 3871
45 S 34 90 215 441 837 1379 2097 2830 3420 3746 3841 3871 3871
50 M 5 12 40 108 245 392 563 578 440 182 28 6 2599
50 S 5 17 57 166 411 803 1366 1944 2384 2565 2594 2599 2599
55 M 0 1 7 42 124 245 408 423 291 73 5 1 1621
55 S 0 2 9 51 175 420 828 1251 1542 1615 1620 1621 1621
60 M 0 0 0 12 53 122 255 269 157 19 0 0 889
60 S 0 0 0 13 66 188 443 712 869 888 889 889 889
Corn Growing Degree Days
50 M 19 41 101 171 283 395 545 561 439 221 57 17 2850
50 S 19 60 161 332 615 1010 1555 2116 2555 2776 2833 2850 2850
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