Pond Evaporation Calculation 1/31/16
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 2015 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec or Avg.
Ovid Avg. Temp F 27.83 30.73 44.94 49.88 54.74 70.97 73.37 71.2 66.09 52.48 35.41 26.37 50.33
Ref date as of 12/31/2015 Total Precip " 0.33 0.43 0.33 2.52 5.59 2.14 0.77 1.5 0.75 1.1 1.24 0.48 17.18
Site Type: Alfalfa Total Alfalfa ETr " 1.96 2.41 6.67 6.09 5.35 8.17 9.07 8.08 6.24 4.01 2.25 1.54 61.84
Total Growing Degee Days from March 1 0 0 245 216 250 610 661 613 496 284 107 28 3510
Gross Pond Evap Total " 1.65 2.02 5.6 5.12 4.49 6.86 7.62 6.79 5.24 3.37 1.89 1.29 51.94
Net Pond Evap Total " 1.42 1.72 5.37 3.35 0.58 5.36 7.08 5.74 4.72 2.6 1.02 0.96 39.92
Crook Avg. Temp F 28.14 31.23 44.48 49.23 54.15 70.35 72.46 71.2 65.73 53.06 35.47 26.07 50.13
Ref date as of 12/31/2015 Total Precip " 0.09 0.19 0.27 5.58 5.44 1.12 1.92 2.82 0.59 1.09 1.51 0.74 21.36
Site Type: Alfalfa Total Alfalfa ETr " 1.94 2.51 6.31 5.74 4.92 7.65 8.29 7.92 6.17 4.34 2.38 1.6 59.77
Total Growing Degee Days from March 1 0 0 243 214 240 604 647 610 505 302 114 33 3512
Gross Pond Evap Inch 1.63 2.11 5.3 4.82 4.13 6.43 6.96 6.65 5.18 3.65 2 1.34 50.2
Net Pond Evap Inch 1.57 1.98 5.11 0.92 0.32 5.64 5.62 4.68 4.77 2.88 0.94 0.83 35.26
 
Sterling Avg. Temp F 26.91 31.89 44.64 49.29 54.3 71 72.94 71.55 65.87 53.08 35.23 25.67 50.2
Ref date as of 12/31/2015 Total Precip " 0.21 0.21 0.32 4.8 7.22 0.55 1.69 0.65 0.54 1.11 1.02 0.57 18.89
Site Type: Alfalfa Total Alfalfa ETr " 1.57 2.48 6.07 5.67 5.13 8.25 8.87 8.19 6.16 4.13 2.33 1.51 60.36
Total Growing Degee Days from March 1 0 0 233 217 244 616 657 621 493 307 118 35 3541
Gross Pond Evap Inch 1.32 2.08 5.1 4.76 4.31 6.93 7.45 6.88 5.17 3.47 1.96 1.27 50.7
Net Pond Evap Inch 1.17 1.94 4.87 1.4 0 6.55 6.27 6.42 4.8 2.69 1.24 0.87 38.22
 
Brush Avg. Temp F 26.72 31.81 44.49 49.03 53.47 71.04 71.57 71 65.23 52.92 34.61 24.71 49.72
Ref date as of 12/31/2015 Total Precip " 0.21 0.3 0.31 6.29 12.19 1.28 1.93 4.28 0.75 2.6 1.06 0.96 32.16
Site Type: Alfalfa Total Alfalfa ETr " 1.44 2.42 6.23 5.96 5.1 8.96 7.91 7.95 5.91 3.85 2.28 1.31 59.32
Total Growing Degee Days from March 1 0 0 234 223 244 610 616 629 511 320 127 31 3545
Gross Pond Evap Inch 1.21 2.03 5.23 5.01 4.28 7.53 6.64 6.68 4.96 3.23 1.92 1.1 49.82
Net Pond Evap Inch 1.06 1.82 5.02 0.6 0 6.63 5.29 3.68 4.44 1.41 1.17 0.43 31.55
 
Fort Morgan Avg. Temp F 27.5 32.14 44.57 49.22 53.26 70.3 71.63 71.19 65.59 53.43 35.06 24.73 49.89
Ref date as of 12/31/2015 Total Precip " 0.17 0.31 0.12 4.98 11.25 1.63 2.85 2.86 0.2 2.3 0.88 0.52 28.07
Site Type: Turf Total Alfalfa ETr " 1.52 2.24 5.34 5.64 4.73 7.73 7.7 6.77 5.64 3.47 2.01 1.15 53.94
Total Growing Degee Days from March 1 0 0 228 227 233 599 644 631 508 311 114 22 3517
Gross Pond Evap Inch 1.28 1.88 4.49 4.74 3.97 6.49 6.47 5.69 4.74 2.91 1.69 0.97 45.32
Net Pond Evap Inch 1.16 1.66 4.4 1.25 0 5.35 4.47 3.68 4.6 1.3 1.07 0.6 29.54
 
Wiggins Avg. Temp F 25.62 30 41.52 45.85 49.52 66.17 67.2 66.5 61.29 52.92 34.72 23.15 47.04
Ref date as of 12/31/2015 Total Precip " 0.25 0.31 0.1 3.24 7.33 0.92 1.17 2.39 0.12 1.46 0.7 0.68 18.67
Site Type: Alfalfa Total Alfalfa ETr " 1.51 2.32 5.47 5.64 4.41 8.38 8.52 8.12 6.33 4.15 2.37 1.31 58.53
Total Growing Degee Days from March 1 0 0 196 184 182 484 536 538 450 314 116 19 3019
Gross Pond Evap Inch 1.27 1.95 4.59 4.74 3.7 7.04 7.16 6.82 5.32 3.49 1.99 1.1 49.17
Net Pond Evap Inch 1.09 1.73 4.52 2.47 0 6.4 6.34 5.15 5.23 2.46 1.5 0.62 37.51
 
Fort Collins East Avg. Temp F 30.15 32.37 43.55 47.61 51.46 68.41 69.66 69.4 64.46 53.03 35.1 26.97 49.35
Ref date as of 12/31/2015 Total Precip " 0.19 0.49 0.23 2.07 5.53 1.82 1.77 0.79 0.18 2.12 1.34 0.6 17.13
Site Type: Alfalfa Total Alfalfa ETr " 2.18 2.76 5.82 5.97 4.31 7.73 8.24 7.99 6.76 3.84 2.44 1.72 59.76
Total Growing Degee Days from March 1 0 0 202 180 194 536 589 583 493 279 89 32 3177
Gross Pond Evap Inch 1.83 2.32 4.89 5.01 3.62 6.49 6.92 6.71 5.68 3.23 2.05 1.44 50.19
Net Pond Evap Inch 1.7 1.98 4.73 3.57 0 5.22 5.68 6.16 5.55 1.74 1.11 1.02 38.46
 
Eaton Avg. Temp F 29.18 32.39 43.69 48.08 52.34 69.39 69.67 69.23 63.83 52.62 34.22 25.28 49.16
Ref date as of 12/31/2015 Total Precip " 0.27 0.77 0.28 2.54 5.69 1.18 2.26 0.95 0.12 2.29 0.96 0.75 18.06
Site Type: Alfalfa Total Alfalfa ETr " 1.83 2.58 5.42 6.03 4.85 8.43 8.08 7.6 6.02 3.54 2.27 1.66 58.31
Total Growing Degee Days from March 1 0 0 212 207 222 558 608 585 495 287 89 19 3282
Gross Pond Evap Inch 1.54 2.17 4.55 5.07 4.07 7.08 6.79 6.38 5.06 2.97 1.91 1.39 48.98
Net Pond Evap Inch 1.35 1.63 4.36 3.29 0.09 6.26 5.21 5.72 4.97 1.37 1.23 0.87 36.35
 
Johnsons Corner Avg. Temp F 32.04 33.1 44.4 48.31 51.65 68.31 70.65 71.13 65.9 53.63 35.9 26.89 50.16
Ref date as of 12/31/2015 Total Precip " 0.27 1.33 0.27 2.28 6.29 3.73 0.43 0.75 0.07 2.07 1.52 0.74 19.75
Site Type: Alfalfa Total Alfalfa ETr " 2.09 2.6 5.17 5.57 4.32 7.6 8.95 8.43 6.58 3.76 2.28 1.65 59
Total Growing Degee Days from March 1 0 0 200 188 196 550 610 611 499 273 78 30 3235
Gross Pond Evap Inch 1.76 2.18 4.34 4.68 3.63 6.38 7.52 7.08 5.53 3.16 1.92 1.39 49.57
Net Pond Evap Inch 1.57 1.25 4.15 3.08 0 3.77 7.22 6.56 5.48 1.71 0.85 0.87 36.51
 
Gilcrest Avg. Temp F 30.91 33.09 44.85 49.52 53.23 70.17 72.13 71.49 65.99 53.34 35.08 24.04 50.32
Ref date as of 12/31/2015 Total Precip " 0.2 0.76 0.21 2.32 5.29 2.95 0.6 1.99 0.09 1.58 1.73 0.69 18.41
Site Type: Alfalfa Total Alfalfa ETr " 1.9 2.41 5.2 5.85 4.62 8.19 8.99 8.18 6.45 3.62 2.15 1.3 58.86
Total Growing Degee Days from March 1 0 0 226 217 228 589 645 628 521 299 94 22 3469
Gross Pond Evap Inch 1.6 2.02 4.37 4.91 3.88 6.88 7.55 6.87 5.42 3.04 1.81 1.09 49.44
Net Pond Evap Inch 1.46 1.49 4.22 3.29 0.18 4.81 7.13 5.48 5.36 1.93 0.6 0.61 36.56
 
Longmont South Avg. Temp F 33.55 34.14 44.85 49.08 52.18 68.8 71.28 72.02 66.85 54.39 37.01 28.27 51.04
Ref date as of 12/31/2015 Total Precip " 0.35 1.42 0.41 3.29 6.33 1.15 0.86 0.68 0.12 1.98 1.82 0.77 19.18
Site Type: Alfalfa Total Alfalfa ETr " 2.48 2.92 5.19 5.51 4.41 7.57 8.32 8.63 6.9 3.86 2.5 1.83 60.12
Total Growing Degee Days from March 1 0 0 195 193 204 537 612 616 515 282 98 35 3287
Gross Pond Evap Inch 2.08 2.45 4.36 4.63 3.7 6.36 6.99 7.25 5.8 3.24 2.1 1.54 50.5
Net Pond Evap Inch 1.84 1.46 4.07 2.33 0 5.55 6.39 6.77 5.71 1.86 0.83 1 37.81
 
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 32.77 34.12 44.64 49.2 52.64 69.65 70.66 70.64 65.24 53.45 34.56 27.34 50.41
Ref date as of 12/31/2015 Total Precip " 0.14 0.7 0.1 3.15 6.08 1.69 1.42 0.94 0.16 1.96 0.73 0.46 17.53
Site Type: Turf Total Alfalfa ETr " 1.87 2.28 4.52 5.05 4.03 6.9 6.87 6.38 5.04 2.8 1.93 1.49 49.16
Total Growing Degee Days from March 1 0 0 214 198 210 556 610 603 512 295 90 34 3322
Gross Pond Evap Inch 1.57 1.92 3.8 4.24 3.39 5.8 5.77 5.36 4.23 2.35 1.62 1.25 41.3
Net Pond Evap Inch 1.47 1.43 3.73 2.04 0 4.61 4.78 4.7 4.12 0.98 1.11 0.93 29.9
 
Windsor 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 7/1/2012 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: Dryland Pasture 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
 
Greeley West Avg. Temp F 30.1 33.32 45.06 49.1 52.84 70.28 72 71.89 66.41 53.78 35.02 25.55 50.45
Ref date as of 12/31/2015 Total Precip " 0.27 0.89 0.3 2.56 5.24 1.89 0.86 0.75 0.14 1.97 1.48 0.84 17.19
Site Type: Turf Total Alfalfa ETr " 1.66 2.27 4.85 5.38 4.46 7.5 8.09 7.28 5.83 3.34 1.92 1.37 53.95
Total Growing Degee Days from March 1 0 0 224 207 218 592 651 630 531 304 89 24 3470
Gross Pond Evap Inch 1.39 1.91 4.07 4.52 3.75 6.3 6.8 6.12 4.9 2.81 1.61 1.15 45.33
Net Pond Evap Inch 1.21 1.28 3.86 2.73 0.08 4.98 6.19 5.59 4.8 1.43 0.58 0.56 33.29
 
Loveland Avg. Temp F 31.63 33.8 44.65 49.53 53.01 70.22 71.61 71.62 66.44 54.24 36.47 28.14 50.95
Ref date as of 12/31/2015 Total Precip " 0.36 1 0.29 2.29 6.18 2.57 0.99 1.17 0.03 2.22 1.13 0.64 18.87
Site Type: Turf Total Alfalfa ETr " 1.75 2.34 4.5 5.04 4.1 6.92 7.32 6.64 5.5 3.22 2.06 1.55 50.94
Total Growing Degee Days from March 1 0 0 232 226 238 604 641 635 543 314 116 34 3583
Gross Pond Evap Inch 1.47 1.97 3.78 4.23 3.44 5.81 6.15 5.58 4.62 2.7 1.73 1.3 42.78
Net Pond Evap Inch 1.22 1.27 3.58 2.63 0 4.01 5.46 4.76 4.6 1.15 0.94 0.85 30.47
 
Berthoud Avg. Temp F 32.71 33.67 44.92 48.61 51.64 68.89 71.25 71.59 66.75 54.51 37.06 28.47 50.84
Ref date as of 12/31/2015 Total Precip " 0.19 1.11 0.28 2.88 6.97 2.35 0.34 0.96 0.05 1.74 1.53 0.7 19.1
Site Type: Turf Total Alfalfa ETr " 1.97 2.44 4.75 5.22 4.23 7.38 8.52 7.74 6.15 3.61 2.28 1.58 55.87
Total Growing Degee Days from March 1 0 0 199 191 194 566 634 628 520 273 85 30 3320
Gross Pond Evap Inch 1.65 2.05 3.99 4.38 3.55 6.2 7.16 6.5 5.17 3.03 1.92 1.33 46.93
Net Pond Evap Inch 1.52 1.27 3.79 2.37 0 4.55 6.92 5.83 5.13 1.81 0.84 0.84 34.87
 
Longmont West Avg. Temp F 32.65 34.15 44.36 48.94 51.94 68.92 70.91 71.51 66.67 54 36.79 29.02 50.82
Ref date as of 12/31/2015 Total Precip " 0.12 0.75 0.26 2.48 5.49 1.58 0.79 0.47 0.34 1.88 1.63 0.34 16.13
Site Type: Turf Total Alfalfa ETr " 1.78 2.25 4.27 4.83 4.07 6.57 7.17 6.56 5.03 2.82 1.86 1.35 48.56
Total Growing Degee Days from March 1 0 0 188 183 194 550 623 628 523 283 93 38 3303
Gross Pond Evap Inch 1.5 1.89 3.59 4.06 3.42 5.52 6.02 5.51 4.23 2.37 1.56 1.13 40.8
Net Pond Evap Inch 1.41 1.37 3.4 2.32 0 4.41 5.47 5.18 3.99 1.05 0.42 0.9 29.92
 
Fort Lupton Avg. Temp F 32.51 33.97 45.14 49.25 52.8 69.62 71.83 72.53 67.54 55.16 36.99 27.44 51.23
Ref date as of 12/31/2015 Total Precip " 0.29 1.21 0.68 2.47 5.45 2.07 1.02 0.54 0.32 1.17 2.38 0.93 18.53
Site Type: Turf Total Alfalfa ETr " 2.12 2.48 4.95 5.66 4.81 7.99 8.55 8.53 6.8 3.97 2.42 1.61 59.89
Total Growing Degee Days from March 1 0 0 208 207 221 576 651 644 545 308 104 30 3494
Gross Pond Evap Inch 1.78 2.08 4.16 4.75 4.04 6.71 7.18 7.17 5.71 3.33 2.03 1.35 50.29
Net Pond Evap Inch 1.58 1.24 3.68 3.03 0.23 5.26 6.47 6.79 5.49 2.52 0.37 0.7 37.36
 
Boulder NW Avg. Temp F 35.72 34.83 45.59 48.94 52.15 69.14 71.09 71.96 67.74 54.69 38.29 30.98 51.76
Ref date as of 12/31/2015 Total Precip " 0.22 2.1 0.57 3.62 6.15 1.63 2.58 0.42 0.33 2 1.43 0.54 21.59
Site Type: Turf Total Alfalfa ETr " 2.21 2.41 4.62 4.71 4.11 7.14 7.41 7.21 6.09 3.36 2.34 1.87 53.48
Total Growing Degee Days from March 1 0 0 201 203 204 547 629 630 538 277 98 43 3370
Gross Pond Evap Inch 1.86 2.02 3.88 3.96 3.45 6 6.22 6.06 5.12 2.82 1.97 1.57 44.93
Net Pond Evap Inch 1.7 0.55 3.48 1.42 0 4.86 4.42 5.76 4.88 1.42 0.96 1.19 30.64
 
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 37.14 36.25 46.73 49.42 52.02 68.9 71.08 71.98 68.31 55.79 39.93 33.56 52.59
Ref date as of 12/31/2015 Total Precip " 0.46 1.69 0.64 4.07 6.35 2.24 2.38 0.38 0.15 2.05 1.23 0.29 21.93
Site Type: Turf Total Alfalfa ETr " 2.46 2.59 4.82 4.96 4.14 7.05 7.2 7.46 6.44 3.63 2.69 2.13 55.57
Total Growing Degee Days from March 1 0 0 176 169 181 557 621 626 518 261 88 45 3242
Gross Pond Evap Inch 2.07 2.18 4.05 4.17 3.48 5.92 6.05 6.27 5.41 3.05 2.26 1.79 46.7
Net Pond Evap Inch 1.74 0.99 3.6 1.32 0 4.35 4.38 6 5.3 1.61 1.4 1.59 32.28
Greeley04 Avg. Temp F 27.76 32.33 43.91 48.65 52.79 69.71 71.42 70.63 65.23 53.3 34.48 24.15 49.53
Ref date as of 12/31/2015 Total Precip " 0.1 0.16 0.13 2.48 5.22 2.24 0.9 0.75 0.07 1.25 1.1 0.2 14.6
Site Type: Fully irrigated Total Alfalfa ETr " 1.93 2.77 5.78 6.3 4.58 8.37 9.54 6.87 6.47 3.97 2.35 1.69 60.62
Total Growing Degee Days from March 1 0 0 230 214 214 577 634 618 513 314 91 18 3423
Gross Pond Evap Inch 1.62 2.33 4.86 5.29 3.85 7.03 8.01 5.77 5.43 3.33 1.97 1.42 50.91
Net Pond Evap Inch 1.55 2.21 4.76 3.56 0.19 5.46 7.38 5.25 5.39 2.46 1.2 1.28 40.69