ARROWROCK DAM, IDAHO

Period of Record General Climate Summary - Growing Degree Days

Station:(100448) ARROWROCK DAM
From Year=1911 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	2	9	74	253	510	728	1037	1005	678	330	52	6	4685
40 S	2	11	85	339	849	1577	2614	3619	4297	4627	4679	4685	4685
45 M	0	1	23	140	360	578	882	850	529	200	14	1	3579
45 S	0	1	24	164	525	1103	1985	2835	3364	3564	3578	3579	3579
50 M	0	0	5	64	227	430	727	695	385	101	2	0	2636
50 S	0	0	5	69	296	725	1453	2148	2532	2634	2636	2636	2636
55 M	0	0	0	23	122	290	573	541	253	40	0	0	1842
55 S	0	0	0	23	145	435	1008	1549	1802	1842	1842	1842	1842
60 M	0	0	0	6	55	171	420	390	143	11	0	0	1195
60 S	0	0	0	6	60	231	650	1040	1183	1195	1195	1195	1195

Corn Growing Degree Days
50 M	0	6	54	165	315	445	637	619	425	219	28	1	2916
50 S	0	7	61	226	541	986	1624	2242	2668	2887	2914	2916	2916

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