PORTAL, ARIZONA

Period of Record General Climate Summary - Growing Degree Days

Station:(026706) PORTAL
From Year=1914 To Year=1955
Growing Degree Days for Selected Base Temperature (F)
Base	Jan.	Feb.	Mar.	Apr.	May	Jun.	Jul.	Aug.	Sep.	Oct.	Nov.	Dec.	Annual
40 M	121	161	293	549	738	986	1088	1019	891	607	281	125	6858
40 S	121	282	575	1123	1862	2848	3936	4955	5846	6453	6734	6858	6858
45 M	48	75	166	402	584	836	933	864	741	453	162	45	5308
45 S	48	123	289	691	1275	2111	3044	3908	4649	5102	5263	5308	5308
50 M	12	23	73	267	430	686	778	709	591	305	72	12	3958
50 S	12	36	109	376	805	1491	2269	2978	3569	3874	3946	3958	3958
55 M	1	4	22	151	284	536	623	554	441	176	20	2	2815
55 S	1	5	27	178	463	999	1621	2175	2616	2793	2813	2815	2815
60 M	0	1	5	65	159	387	468	399	294	82	3	0	1862
60 S	0	1	6	71	230	617	1085	1484	1777	1859	1862	1862	1862

Corn Growing Degree Days
50 M	111	143	237	380	508	632	706	672	583	408	220	118	4719
50 S	111	254	491	871	1379	2011	2718	3390	3972	4380	4600	4719	4719

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