ST MARY, MONTANA

Period of Record General Climate Summary - Growing Degree Days

Station:(247292) ST MARY
From Year=1981 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	6	10	23	97	269	463	697	686	402	175	30	4	2864
40 S	6	17	40	137	406	869	1567	2253	2654	2830	2860	2864	2864
45 M	1	2	5	40	153	318	542	532	270	90	10	0	1963
45 S	1	3	8	48	201	519	1061	1593	1863	1953	1963	1963	1963
50 M	0	0	0	12	71	188	389	380	157	37	3	0	1238
50 S	0	0	1	13	84	272	661	1041	1199	1235	1238	1238	1238
55 M	0	0	0	2	26	91	245	240	76	12	0	0	692
55 S	0	0	0	2	28	119	364	604	680	691	692	692	692
60 M	0	0	0	0	6	33	123	120	27	3	0	0	313
60 S	0	0	0	0	6	39	163	283	310	313	313	313	313

Corn Growing Degree Days
50 M	2	6	16	77	182	286	439	443	272	106	13	1	1842
50 S	2	7	23	100	283	568	1007	1450	1721	1828	1841	1842	1842

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