MERWIN DAM, WASHINGTON

Period of Record General Climate Summary - Growing Degree Days

Station:(455305) MERWIN DAM
From Year=1971 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 60 454 151 299 511 -99 864 882 611 493 228 110 -99
40 S 60 514 665 964 1474 -99 -99 -99 -99 -99 -99 -99 -99
45 M 14 368 52 164 356 -99 709 727 461 338 106 28 -99
45 S 14 382 434 599 954 -99 -99 -99 -99 -99 -99 -99 -99
50 M 0 338 10 81 203 -99 554 572 313 188 40 1 -99
50 S 0 338 348 429 632 -99 -99 -99 -99 -99 -99 -99 -99
55 M 0 329 1 34 83 -99 399 417 174 71 8 0 -99
55 S 0 329 329 363 446 -99 -99 -99 -99 -99 -99 -99 -99
60 M 0 323 0 8 25 -99 245 265 65 18 1 0 -99
60 S 0 323 323 331 356 -99 -99 -99 -99 -99 -99 -99 -99
Corn Growing Degree Days
50 M 14 315 49 144 258 -99 534 531 327 247 63 8 -99
50 S 14 329 378 522 780 -99 -99 -99 -99 -99 -99 -99 -99
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