BOULDER, COLORADO

Period of Record General Climate Summary - Growing Degree Days

Station:(050848) BOULDER
From Year=1893 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	47	60	139	293	539	801	1008	965	692	405	146	57	5151
40 S	47	106	246	539	1078	1879	2887	3851	4543	4948	5094	5151	5151
45 M	16	23	69	179	391	651	853	810	544	270	72	21	3899
45 S	16	39	107	286	677	1328	2181	2991	3535	3805	3878	3899	3899
50 M	4	6	28	92	254	502	698	655	401	157	27	6	2829
50 S	4	10	38	130	384	886	1584	2239	2639	2796	2823	2829	2829
55 M	0	1	8	37	141	357	543	500	265	73	7	1	1934
55 S	0	2	10	47	188	545	1088	1587	1853	1926	1933	1934	1934
60 M	0	0	1	10	61	223	389	346	148	25	1	0	1204
60 S	0	0	2	12	72	295	684	1030	1178	1202	1203	1204	1204

Corn Growing Degree Days
50 M	40	49	108	197	331	501	655	628	439	265	108	47	3368
50 S	40	89	197	394	725	1226	1881	2509	2948	3213	3321	3368	3368

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