SAINT JOHNS, ARIZONA

Period of Record General Climate Summary - Growing Degree Days

Station:(027435) SAINT JOHNS
From Year=1901 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	19	55	168	360	619	864	1047	983	761	444	124	23	5468
40 S	19	74	242	602	1221	2086	3132	4115	4877	5321	5445	5468	5468
45 M	3	14	74	225	466	714	892	828	611	297	46	5	4175
45 S	3	17	90	315	781	1495	2387	3215	3827	4124	4170	4175	4175
50 M	0	2	21	112	317	564	737	673	462	166	10	0	3065
50 S	0	2	24	136	453	1018	1754	2428	2889	3055	3064	3065	3065
55 M	0	0	3	38	182	415	582	518	314	67	1	0	2120
55 S	0	0	3	42	223	638	1220	1738	2052	2119	2120	2120	2120
60 M	0	0	0	7	77	268	427	363	173	16	0	0	1332
60 S	0	0	0	8	84	353	779	1142	1316	1332	1332	1332	1332

Corn Growing Degree Days
50 M	46	92	182	302	440	551	662	631	502	350	160	55	3974
50 S	46	138	321	622	1063	1614	2276	2906	3409	3759	3918	3974	3974

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