WEST YELLOWSTONE, MONTANA

Period of Record General Climate Summary - Growing Degree Days

Station:(248857) WEST YELLOWSTONE
From Year=1924 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	0	0	1	20	163	361	602	533	255	52	1	0	1988
40 S	0	0	1	21	184	545	1147	1680	1935	1987	1988	1988	1988
45 M	0	0	0	4	71	225	447	379	137	12	0	0	1275
45 S	0	0	0	4	75	300	747	1126	1263	1275	1275	1275	1275
50 M	0	0	0	0	21	114	295	232	52	1	0	0	715
50 S	0	0	0	0	21	135	430	662	714	715	715	715	715
55 M	0	0	0	0	3	41	154	105	12	0	0	0	314
55 S	0	0	0	0	3	44	198	303	314	314	314	314	314
60 M	0	0	0	0	0	9	50	26	1	0	0	0	85
60 S	0	0	0	0	0	9	59	84	85	85	85	85	85

Corn Growing Degree Days
50 M	0	0	5	41	163	281	448	419	254	95	4	0	1711
50 S	0	0	5	46	209	490	938	1357	1612	1707	1711	1711	1711

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