LEWISTOWN FAA AP, MONTANA

Period of Record General Climate Summary - Growing Degree Days

Station:(244985) LEWISTOWN FAA AP
From Year=1896 To Year=2006
Growing Degree Days for Selected Base Temperature (F)
Base Jan. Feb. Mar. Apr. May Jun. Jul. Aug. Sep. Oct. Nov. Dec. Annual
40 M 8 11 36 134 330 542 789 753 442 218 49 12 3322
40 S 8 19 55 188 518 1060 1849 2602 3044 3262 3311 3322 3322
45 M 2 2 12 64 202 394 634 598 308 121 17 3 2357
45 S 2 4 16 81 283 676 1311 1909 2216 2337 2355 2357 2357
50 M 0 0 4 25 104 254 480 444 190 55 4 0 1561
50 S 0 0 4 29 133 387 866 1311 1501 1556 1560 1561 1561
55 M 0 0 1 7 44 138 329 297 99 18 1 0 933
55 S 0 0 1 8 51 189 518 815 914 932 933 933 933
60 M 0 0 0 1 14 60 191 166 39 4 0 0 476
60 S 0 0 0 2 15 75 267 433 473 476 476 476 476
Corn Growing Degree Days
50 M 5 10 33 112 221 330 496 476 296 169 43 9 2200
50 S 5 15 49 161 381 711 1207 1683 1978 2147 2191 2200 2200
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 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