MODESTO, CALIFORNIA

Period of Record General Climate Summary - Growing Degree Days

Station:(045738) MODESTO
From Year=1931 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 190 309 470 603 818 969 1147 1098 954 738 393 199 7889
40 S 190 499 970 1573 2391 3359 4506 5605 6559 7297 7690 7889 7889
45 M 81 177 316 453 663 819 992 943 804 583 247 85 6163
45 S 81 258 574 1027 1690 2508 3500 4444 5248 5831 6078 6163 6163
50 M 23 72 173 305 508 669 837 788 654 429 122 24 4604
50 S 23 95 268 574 1081 1750 2587 3375 4030 4459 4580 4604 4604
55 M 4 18 68 171 354 519 682 633 504 277 41 4 3275
55 S 4 22 90 261 615 1134 1816 2449 2953 3231 3272 3275 3275
60 M 0 2 16 73 212 370 527 478 355 144 8 0 2185
60 S 0 2 18 92 303 673 1200 1679 2033 2177 2185 2185 2185
Corn Growing Degree Days
50 M 78 158 266 358 501 603 706 685 600 454 221 86 4715
50 S 78 237 502 860 1362 1965 2671 3355 3955 4409 4630 4715 4715
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