Pond Evaporation Calculation													12/31/14
Weather Station Data provided by Northern Colorado Water Conservancy District
See Weather Station Location Map at:
http://www.northernwater.org/WaterConservation/WeatherandETData.aspx
Notes:
Current month reflects values through "Reference Date".
Pond Evap. calculated per recent Division 1 Water Court decree language:							Lower South Platte Home Page
Gross Pond = .84(Alfalfa ETr)							Pond Evaporation Reports Main Menu
Net Pond = .84(Alfalfa ETr) - .7(Total Precip)
Alfalfa reference ETr computed by Standard ASCE equation from daily weather data.
Winter pond evap. is a reference for unfrozen ponds.
For Growing Degree Days:
Tmax = 86° F, Tmin = 50° F and Tbase = 50° F
														Totals
Weather Station	2013	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec	or Avg.
Ovid	Avg. Temp ° F	26.41	29.69	37.33	42.96	58.87	70.53	74.29	74.48	67.56	46.97	36.34	25.34	49.23
Ref date as of 12/31/2013	Total Precip "	0.36	0.62	0.45	1.27	1.56	1.91	1.49	1.47	2.49	0.98	0.52	0.15	13.27
Site Type: Alfalfa	Total Alfalfa ETr "	1.89	2.36	4.35	5.83	8.55	10.48	9.72	8.4	6.45	4.07	2.63	2.16	66.89
Total Growing Degee Days from March 1		0	0	103	172	376	573	691	681	525	200	110	57	3488
Gross Pond Evap	Total "	1.59	1.98	3.65	4.9	7.18	8.8	8.16	7.06	5.42	3.42	2.21	1.81	56.18
Net Pond Evap	Total "	1.34	1.55	3.34	4.01	6.09	7.47	7.12	6.03	3.68	2.73	1.85	1.71	46.92
Crook	Avg. Temp ° F	26.91	29.74	37.68	42.36	57.83	69.94	72.38	72.25	65.62	46.29	35.8	25.31	48.51
Ref date as of 12/31/2013	Total Precip "	0.24	0.43	0.24	1.24	2.53	1.09	2.6	1.23	4.2	1.01	0.36	0.1	15.27
Site Type: Alfalfa	Total Alfalfa ETr "	1.98	2.41	4.51	5.29	7.59	10.34	8.75	7.58	5.52	3.88	2.63	2.15	62.63
Total Growing Degee Days from March 1		0	0	109	161	359	563	653	631	491	188	108	57	3320
Gross Pond Evap	Inch	1.66	2.02	3.79	4.44	6.38	8.69	7.35	6.37	4.64	3.26	2.21	1.81	52.62
Net Pond Evap	Inch	1.5	1.72	3.62	3.58	4.6	7.92	5.53	5.51	1.7	2.55	1.96	1.74	41.93
Sterling	Avg. Temp ° F	27.23	30.23	38.13	42.99	58.99	71.38	73.04	72.19	66.03	46.69	36.85	25.54	49.11
Ref date as of 12/31/2013	Total Precip "	0.33	0.52	0.41	1.84	1.31	1.13	5.47	1.15	6.28	1.32	0.32	0.06	20.14
Site Type: Alfalfa	Total Alfalfa ETr "	1.98	2.39	4.47	5.23	8.61	10.99	8.82	7.28	5.54	3.79	2.6	2.09	63.79
Total Growing Degee Days from March 1		0	0	121	159	373	587	667	641	497	188	122	55	3410
Gross Pond Evap	Inch	1.66	2.01	3.75	4.39	7.23	9.23	7.41	6.12	4.65	3.18	2.18	1.76	53.57
Net Pond Evap	Inch	1.43	1.64	3.47	3.11	6.32	8.44	3.58	5.31	0.26	2.26	1.96	1.71	39.49
Brush	Avg. Temp ° F	26.18	28.45	36	42.2	57.68	69.87	71.45	71.51	64.94	46.48	37.24	25.6	48.13
Ref date as of 12/31/2013	Total Precip "	0.33	0.37	0.93	1.31	0.86	1.14	3.07	3.17	4.48	1.42	0.22	0.21	17.51
Site Type: Alfalfa	Total Alfalfa ETr "	2.11	2.47	3.88	5.26	8.22	10.22	8.9	7.47	5.34	3.8	2.63	2	62.3
Total Growing Degee Days from March 1		0	0	107	158	357	559	637	637	481	201	123	58	3318
Gross Pond Evap	Inch	1.77	2.07	3.26	4.42	6.9	8.58	7.48	6.27	4.49	3.19	2.21	1.68	52.32
Net Pond Evap	Inch	1.54	1.82	2.61	3.5	6.3	7.79	5.33	4.06	1.35	2.2	2.06	1.53	40.09
Fort Morgan	Avg. Temp ° F	27.14	29.4	37.2	42.9	58.98	71.31	72.52	72.13	65.42	46.24	36.77	24.64	48.72
Ref date as of 12/31/2013	Total Precip "	0.2	0.37	1.22	1.36	1.25	1.59	1.84	1.8	4.22	1.45	0.21	0.21	15.72
Site Type: Turf	Total Alfalfa ETr "	1.92	2.26	3.63	4.92	8.29	9.88	8.87	7.7	5.24	3.39	2.25	1.57	59.92
Total Growing Degee Days from March 1		0	0	115	162	379	578	658	645	490	189	109	48	3373
Gross Pond Evap	Inch	1.61	1.9	3.05	4.13	6.96	8.3	7.45	6.47	4.4	2.85	1.89	1.32	50.33
Net Pond Evap	Inch	1.47	1.64	2.2	3.18	6.09	7.19	6.16	5.21	1.45	1.83	1.74	1.17	39.33
Wiggins	Avg. Temp ° F	24.66	27.03	34.99	40.91	56.78	69.77	72.02	71.84	64.54	45.71	36.17	24.22	47.39
Ref date as of 12/31/2013	Total Precip "	0.25	0.26	0.87	1.37	0.68	0.74	0.69	1.02	3.66	1.25	0.16	0.26	11.21
Site Type: Alfalfa	Total Alfalfa ETr "	2.01	2.34	3.76	5.04	7.83	11	9.69	8.12	5.4	3.75	2.63	1.74	63.31
Total Growing Degee Days from March 1		0	0	97	145	354	553	626	637	479	192	118	51	3252
Gross Pond Evap	Inch	1.69	1.97	3.16	4.23	6.58	9.24	8.14	6.82	4.54	3.15	2.21	1.46	53.19
Net Pond Evap	Inch	1.51	1.78	2.55	3.27	6.1	8.72	7.66	6.11	1.97	2.28	2.1	1.28	45.33
Fort Collins East	Avg. Temp ° F	26.23	28.41	36.78	40.96	56.62	68.7	70	69.5	62.02	44.84	35.93	24.93	47.08
Ref date as of 12/31/2013	Total Precip "	0.24	0.32	0.5	2.27	1.9	1.44	1.52	0.6	4.72	1.27	0.18	0.23	15.19
Site Type: Alfalfa	Total Alfalfa ETr "	2.22	2.63	4.66	5.19	8.37	10.27	8.05	7.12	4.94	3.53	2.76	2.03	61.77
Total Growing Degee Days from March 1		0	0	102	139	334	522	600	584	434	157	89	34	2995
Gross Pond Evap	Inch	1.86	2.21	3.91	4.36	7.03	8.63	6.76	5.98	4.15	2.97	2.32	1.71	51.89
Net Pond Evap	Inch	1.7	1.99	3.56	2.77	5.7	7.62	5.7	5.56	0.85	2.08	2.19	1.54	41.26
Eaton	Avg. Temp ° F	25.8	28.45	36.64	41.15	56.66	68.86	69.9	70.12	62.22	44.84	35.48	24.19	47.03
Ref date as of 12/31/2013	Total Precip "	0.37	0.32	0.65	1.93	2.3	0.55	1.32	1.05	4.11	1.22	0.23	0.35	14.4
Site Type: Alfalfa	Total Alfalfa ETr "	1.99	2.37	4.25	4.88	8.11	10.14	7.98	7.19	4.95	3.4	2.49	1.7	59.45
Total Growing Degee Days from March 1		0	0	102	146	341	537	613	605	444	169	98	35	3090
Gross Pond Evap	Inch	1.67	1.99	3.57	4.1	6.81	8.52	6.7	6.04	4.16	2.86	2.09	1.43	49.94
Net Pond Evap	Inch	1.41	1.77	3.12	2.75	5.2	8.13	5.78	5.3	1.28	2	1.93	1.18	39.85
Johnsons Corner	Avg. Temp ° F	28.64	29.18	37.63	41.9	57.65	70.52	71.69	72.22	64.12	46.1	37.54	26.13	48.61
Ref date as of 12/31/2013	Total Precip "	0.15	0.86	0.93	2.76	1.77	0.64	0.68	0.27	5.65	0.98	0.38	0.5	15.57
Site Type: Alfalfa	Total Alfalfa ETr "	2.14	2.3	4.03	4.65	7.13	9.82	8.24	8.08	5.21	3.48	2.57	2.03	59.68
Total Growing Degee Days from March 1		0	0	106	150	349	558	647	638	464	165	100	37	3214
Gross Pond Evap	Inch	1.8	1.93	3.39	3.91	5.99	8.25	6.92	6.79	4.38	2.92	2.16	1.71	50.15
Net Pond Evap	Inch	1.69	1.33	2.73	1.97	4.75	7.8	6.45	6.6	0.42	2.24	1.89	1.36	39.23
Gilcrest	Avg. Temp ° F	26.15	28.47	37.44	42.94	58.51	71.29	72.46	72.3	64.01	45.43	36.35	24.38	48.31
Ref date as of 12/31/2013	Total Precip "	0.16	0.74	0.9	1.92	1.54	1.5	1.12	1.21	8.06	1.11	0.22	0.4	18.88
Site Type: Alfalfa	Total Alfalfa ETr "	1.78	2.28	3.92	4.6	7.6	10.16	8.57	7.81	5.17	3.3	2.4	1.72	59.31
Total Growing Degee Days from March 1		0	0	113	160	371	570	663	650	471	175	111	42	3326
Gross Pond Evap	Inch	1.5	1.92	3.29	3.86	6.38	8.53	7.2	6.56	4.34	2.77	2.02	1.44	49.81
Net Pond Evap	Inch	1.38	1.4	2.66	2.52	5.31	7.48	6.41	5.71	0	2	1.86	1.16	37.89
Longmont South	Avg. Temp ° F	30.47	30.69	39.24	43.11	58.31	70.7	72.07	71.48	63.4	45.82	38.85	28.08	49.35
Ref date as of 12/31/2013	Total Precip "	0.2	0.69	0.84	2.38	1.8	0.37	0.69	1.27	8.92	1.24	0.28	0.36	19.04
Site Type: Alfalfa	Total Alfalfa ETr "	2.55	2.65	4.26	5.15	7.84	9.77	8.46	7.64	5.17	3.24	2.84	2.48	62.05
Total Growing Degee Days from March 1		0	0	119	159	359	551	643	630	439	154	113	49	3216
Gross Pond Evap	Inch	2.14	2.23	3.58	4.33	6.59	8.21	7.11	6.42	4.34	2.72	2.39	2.08	52.14
Net Pond Evap	Inch	2	1.74	2.99	2.66	5.33	7.95	6.62	5.53	0	1.85	2.19	1.83	40.69
Fort Collins NW	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 12/31/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Fort Collins Central	Avg. Temp ° F	27.91	29.47	37.93	41.48	57.3	69.08	70.89	70.52	62.44	45.01	36.92	25.87	47.9
Ref date as of 12/31/2013	Total Precip "	0.11	0.35	0.47	1.74	2.32	0.41	1.62	0.57	6.49	1.74	0.2	0.27	16.29
Site Type: Turf	Total Alfalfa ETr "	1.72	2.15	3.87	4.24	6.92	8.34	6.98	6.08	4.19	2.91	2.16	1.55	51.11
Total Growing Degee Days from March 1		0	0	101	140	337	532	627	599	444	170	108	50	3108
Gross Pond Evap	Inch	1.44	1.81	3.25	3.56	5.81	7.01	5.86	5.11	3.52	2.44	1.81	1.3	42.92
Net Pond Evap	Inch	1.37	1.56	2.92	2.34	4.19	6.72	4.73	4.71	0	1.23	1.67	1.11	32.55
Windsor	Avg. Temp ° F	34.73	30.75	49.32	54.56	60.53	75.1	80.1	#N/A	#N/A	#N/A	#N/A	#N/A	55.01
Ref date as of 7/1/2012	Total Precip "	0.02	0.47	0.03	1.07	1.6	0.05	0	#N/A	#N/A	#N/A	#N/A	#N/A	3.24
Site Type: Dryland Pasture	Total Alfalfa ETr "	2.56	2.44	6.69	6.86	6.23	6.65	0	#N/A	#N/A	#N/A	#N/A	#N/A	31.43
Total Growing Degee Days from March 1		0	0	285	312	399	622	22	#N/A	#N/A	#N/A	#N/A	#N/A	1640
Gross Pond Evap	Inch	2.15	2.05	5.62	5.76	5.23	5.59	0	#N/A	#N/A	#N/A	#N/A	#N/A	26.4
Net Pond Evap	Inch	2.14	1.72	5.6	5.01	4.11	5.55	0	#N/A	#N/A	#N/A	#N/A	#N/A	24.13
Greeley West	Avg. Temp ° F	25.82	28	36.51	41.4	57.51	70.17	71.89	72.21	64.02	45.71	36.31	24.27	47.82
Ref date as of 12/31/2013	Total Precip "	0.23	0.63	0.83	2.12	1.55	0.36	1.43	2.47	5.43	1.16	0.36	0.48	17.05
Site Type: Turf	Total Alfalfa ETr "	1.58	2.09	3.82	4.48	7.48	9.15	8.04	7.13	4.87	3.13	2.09	1.39	55.25
Total Growing Degee Days from March 1		0	0	93	144	354	562	656	646	476	172	99	33	3235
Gross Pond Evap	Inch	1.33	1.76	3.21	3.76	6.28	7.69	6.75	5.99	4.09	2.63	1.76	1.17	46.42
Net Pond Evap	Inch	1.17	1.31	2.63	2.28	5.2	7.43	5.75	4.26	0.29	1.82	1.5	0.83	34.47
Loveland	Avg. Temp ° F	28.32	29.13	38.07	42.25	57.86	70	72.04	72.14	63.96	46.33	38.31	26.64	48.75
Ref date as of 12/31/2013	Total Precip "	0.03	0.43	0.42	2.22	2.02	1.14	1.39	0.4	7.2	1.08	0.36	0.23	16.92
Site Type: Turf	Total Alfalfa ETr "	1.7	2.09	3.72	4.27	6.67	7.74	6.73	5.95	4.21	2.95	2.14	1.58	49.75
Total Growing Degee Days from March 1		0	0	114	164	363	577	682	656	483	192	124	54	3409
Gross Pond Evap	Inch	1.43	1.76	3.12	3.59	5.6	6.5	5.65	5	3.54	2.48	1.8	1.33	41.8
Net Pond Evap	Inch	1.41	1.45	2.83	2.03	4.19	5.7	4.68	4.72	0	1.72	1.55	1.17	31.45
Berthoud	Avg. Temp ° F	28.52	28.74	36.94	40.95	56.99	69.3	70.7	71.47	63.51	45.59	37.75	26.71	48.1
Ref date as of 12/31/2013	Total Precip "	0.1	0.7	0.77	2.9	1.92	0.4	1.39	0.23	5.48	1.14	0.3	0.48	15.81
Site Type: Turf	Total Alfalfa ETr "	1.87	2.16	3.72	4.29	7.06	8.39	7.37	7.19	4.8	3.17	2.36	1.86	54.24
Total Growing Degee Days from March 1		0	0	88	130	333	546	639	638	449	152	88	32	3095
Gross Pond Evap	Inch	1.57	1.81	3.12	3.6	5.93	7.05	6.19	6.04	4.03	2.66	1.98	1.56	45.54
Net Pond Evap	Inch	1.5	1.32	2.59	1.57	4.59	6.77	5.22	5.88	0.2	1.86	1.77	1.23	34.5
Longmont West	Avg. Temp ° F	29.25	30.07	38.62	42.61	58.45	70.57	72.32	72.76	64.42	46.5	39.82	28.82	49.52
Ref date as of 12/31/2013	Total Precip "	0.06	0.34	0.54	1.87	1.68	0.14	0.63	0.67	7.84	1.18	0.16	0.19	15.3
Site Type: Turf	Total Alfalfa ETr "	1.8	2.09	3.52	4.28	6.76	7.97	7.26	6.61	4.21	2.73	2.28	1.75	51.26
Total Growing Degee Days from March 1		0	0	100	143	347	565	667	655	471	176	119	55	3298
Gross Pond Evap	Inch	1.51	1.76	2.96	3.6	5.68	6.69	6.1	5.55	3.54	2.29	1.92	1.47	43.07
Net Pond Evap	Inch	1.47	1.52	2.58	2.29	4.5	6.6	5.66	5.08	0	1.47	1.8	1.34	34.31
Fort Lupton	Avg. Temp ° F	28.74	29.89	37.9	42.36	57.59	70.38	72.34	72.59	65.04	47.15	40.03	28.53	49.38
Ref date as of 12/31/2013	Total Precip "	0.32	0.73	0.8	1.57	1.27	0.41	0.75	0.96	8.5	0.98	0.25	0.32	16.86
Site Type: Turf	Total Alfalfa ETr "	2.08	2.43	4.01	4.95	7.66	10.31	9.03	8.17	5.4	3.65	2.82	2.22	62.73
Total Growing Degee Days from March 1		0	0	103	154	360	562	653	666	491	182	142	60	3373
Gross Pond Evap	Inch	1.75	2.04	3.37	4.16	6.43	8.66	7.59	6.86	4.54	3.07	2.37	1.86	52.7
Net Pond Evap	Inch	1.52	1.53	2.81	3.06	5.55	8.37	7.06	6.19	0	2.38	2.19	1.64	42.3
Boulder NW	Avg. Temp ° F	37.65	29.64	50.39	53.79	60.03	74.83	75.52	73.33	64.89	49.14	44.06	32.86	53.84
Ref date as of 12/31/2012	Total Precip "	0.17	0.9	0.01	1.2	1.64	0.63	3.28	0.24	2.33	1.02	0.24	0.26	11.92
Site Type: Turf	Total Alfalfa ETr "	3.02	2.28	5.99	6.28	7.09	8.53	8	7.62	5.53	3.55	2.65	2.06	62.6
Total Growing Degee Days from March 1		0	0	273	293	393	633	718	655	468	224	146	51	3854
Gross Pond Evap	Inch	2.54	1.92	5.03	5.28	5.96	7.17	6.72	6.4	4.65	2.98	2.23	1.73	52.61
Net Pond Evap	Inch	2.42	1.29	5.02	4.44	4.81	6.72	4.42	6.23	3.01	2.27	2.06	1.55	44.24
Boulder East	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 5/2/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Boulder Flatiron	Avg. Temp ° F	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Ref date as of 5/2/2010	Total Precip "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Site Type: Turf	Total Alfalfa ETr "	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Total Growing Degee Days from March 1		0	0	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Gross Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Net Pond Evap	Inch	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	#N/A	0
Boulder SW	Avg. Temp ° F	40.24	31.02	51.87	54.59	59.64	74.08	74.75	72.96	65.1	49.83	46.06	34.28	54.54
Ref date as of 12/31/2012	Total Precip "	0.15	0.79	0	1.31	1.63	0.42	3.96	0.27	2.24	1.13	0.1	0.18	12.18
Site Type: Turf	Total Alfalfa ETr "	3.62	2.47	6.34	6.71	7.29	9.64	8.4	7.83	5.83	3.74	3.02	2.29	67.18
Total Growing Degee Days from March 1		0	0	238	266	348	565	700	622	435	203	133	44	3554
Gross Pond Evap	Inch	3.04	2.07	5.33	5.64	6.12	8.1	7.06	6.58	4.9	3.14	2.54	1.92	56.44
Net Pond Evap	Inch	2.94	1.52	5.33	4.72	4.98	7.8	4.28	6.39	3.33	2.35	2.47	1.8	47.91
Greeley04	Avg. Temp ° F	24.83	27.47	36.34	41.56	57.76	69.96	70.82	70.59	63.17	45.22	35.62	23.49	47.24
Ref date as of 12/31/2013	Total Precip "	0.04	0.24	0.33	0.77	1.57	0.33	1.13	1.4	4.03	1.05	0.11	0.11	11.11
Site Type: Fully irrigated	Total Alfalfa ETr "	2.17	2.66	4.44	5.31	8.71	11.01	8.96	7.26	5.3	3.42	2.95	1.99	64.18
Total Growing Degee Days from March 1		0	0	98	147	362	554	622	618	472	180	105	32	3190
Gross Pond Evap	Inch	1.82	2.23	3.73	4.46	7.32	9.25	7.53	6.1	4.45	2.87	2.48	1.67	53.91
Net Pond Evap	Inch	1.79	2.07	3.5	3.92	6.22	9.02	6.74	5.12	1.63	2.14	2.4	1.59	46.14