Historical and modeled monthly values for Lake Michigan for the 64 months prior to the forecast outlooks starting 03May2018 Year Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total Basin Runoff to Lake (mm) 2013 41.03 49.12 51.14 97.83 85.30 47.50 32.14 27.49 21.43 30.72 58.82 42.65 2014 41.64 33.35 45.88 72.36 72.36 42.45 29.11 24.66 41.64 54.78 45.28 50.74 2015 40.02 27.29 36.59 53.97 49.32 45.28 29.71 21.22 23.45 24.26 39.62 59.02 2016 53.36 43.86 54.98 64.88 48.92 33.15 24.46 27.69 26.28 38.81 31.73 40.02 2017 48.31 42.65 57.00 71.15 66.70 43.26 31.33 27.69 21.43 57.61 61.45 45.08 2018 39.82 48.31 53.16 53.16 - - - - - - - - Total Over-Lake Precipitation (mm) 2013 61.11 41.29 30.52 113.84 72.59 85.16 63.83 64.93 46.85 83.46 70.76 30.90 2014 32.18 26.42 27.02 77.40 70.10 100.18 59.98 82.07 83.41 87.80 62.08 39.30 2015 17.28 15.63 15.04 54.34 91.61 88.20 52.78 68.02 71.99 54.60 57.97 78.31 2016 30.69 22.31 74.12 43.77 56.89 66.28 77.55 96.15 83.28 73.86 41.10 34.98 2017 48.52 31.27 54.50 94.29 70.84 103.67 66.24 75.28 37.26 127.98 44.78 28.45 2018 28.32 55.38 21.94 46.48 - - - - - - - - Total Lake Evaporation (mm) 2013 106.53 60.93 41.16 18.54 3.86 9.69 48.74 42.24 76.52 83.24 109.57 118.69 2014 91.64 45.66 28.48 4.25 -2.00 -4.40 16.05 30.40 64.05 68.61 110.37 68.86 2015 74.81 58.52 21.91 5.12 -2.18 1.02 26.31 61.34 48.58 87.14 71.79 68.51 2016 103.67 56.71 21.91 26.93 17.76 27.89 38.50 53.87 71.76 69.54 70.93 143.64 2017 84.31 55.66 46.76 11.97 25.83 22.74 34.09 64.93 55.94 82.54 102.92 125.68 2018 91.51 40.64 44.19 37.75 - - - - - - - - Total Net Basin Supply to Lake (mm) 2013 -4.39 29.49 40.50 193.13 154.03 122.97 47.23 50.18 -8.24 30.94 20.01 -45.14 2014 -17.82 14.11 44.43 145.52 144.46 147.03 73.04 76.33 61.00 73.97 -3.01 21.18 2015 -17.51 -15.60 29.72 103.19 143.11 132.45 56.18 27.90 46.85 -8.29 25.79 68.82 2016 -19.62 9.46 107.19 81.73 88.05 71.54 63.51 69.97 37.79 43.13 1.91 -68.64 2017 12.52 18.27 64.75 153.47 111.71 124.18 63.48 38.05 2.74 103.06 3.31 -52.15 2018 -23.38 63.05 30.91 61.90 - - - - - - - - Average Over-Land Air Temperature (C) 2013 -4.48 -5.53 -2.10 5.09 14.23 18.20 20.83 19.79 16.26 9.93 1.94 -6.89 2014 -10.38 -10.44 -4.28 5.94 13.34 19.14 18.69 19.66 15.32 9.07 -0.81 -1.96 2015 -7.32 -11.73 -0.33 7.25 14.68 17.70 20.31 19.72 18.52 10.20 5.79 2.45 2016 -5.13 -2.97 3.22 6.02 13.72 18.95 21.60 21.74 18.15 11.47 6.71 -3.75 2017 -3.61 -0.27 0.14 9.22 12.26 19.11 20.79 18.63 17.35 11.76 2.17 -5.69 2018 -5.66 -4.62 -0.59 2.39 - - - - - - - - Average Lake Surface Temperature (C) 2013 5.23 2.25 1.21 2.92 6.28 14.26 20.10 20.07 18.55 13.95 8.73 5.60 2014 1.19 0.00 0.00 0.17 2.75 7.64 15.76 19.36 17.45 12.19 7.76 5.11 2015 0.99 0.00 0.00 1.58 3.86 11.68 18.82 20.62 18.88 13.23 9.42 7.06 2016 5.08 2.58 2.87 4.45 10.10 16.92 21.17 23.02 20.32 14.93 10.85 7.34 2017 5.00 3.61 2.59 5.38 10.16 16.47 20.43 20.71 18.27 14.93 9.30 6.55 2018 3.81 0.42 2.30 3.09 - - - - - - - - Average Over-Lake Air Temperature (C) 2013 -0.58 -2.41 -0.71 3.95 9.11 15.56 20.23 20.00 17.67 12.10 5.05 -1.82 2014 -6.30 -7.65 -3.36 2.82 6.86 11.55 16.84 19.52 16.45 10.87 3.10 1.12 2015 -4.09 -8.16 -0.61 4.22 7.90 13.86 19.43 20.35 18.72 11.97 7.50 4.52 2016 -1.04 -0.69 2.76 4.79 11.37 17.56 21.34 22.58 19.69 13.40 8.78 0.94 2017 -0.16 1.26 0.93 6.85 10.82 17.43 20.49 20.01 17.96 13.60 5.58 -0.44 2018 -1.78 -2.83 0.72 2.42 - - - - - - - - Average Over-Lake Vapor Pressure (mb) 2013 4.30 3.87 4.23 6.25 9.39 14.71 19.03 18.83 15.57 10.88 6.30 3.93 2014 2.91 2.51 3.62 5.82 8.28 12.11 15.80 19.02 15.04 10.07 5.56 5.20 2015 3.32 2.31 4.26 6.15 8.89 13.57 18.12 19.34 17.73 10.28 7.78 6.75 2016 4.14 4.37 5.98 6.46 10.41 15.78 20.91 22.60 18.39 12.43 8.89 4.66 2017 4.85 5.05 4.95 7.75 10.12 16.13 20.05 18.81 16.36 12.04 6.26 4.20 2018 4.10 3.85 4.40 5.06 - - - - - - - - Average Over-Lake Wind Speed (m/s) 2013 7.26 6.74 5.90 5.43 4.27 3.78 4.25 4.05 4.96 5.59 7.27 7.17 2014 7.69 6.42 5.58 4.91 4.24 3.91 3.95 3.85 4.86 5.70 7.22 6.14 2015 6.78 6.69 5.19 4.56 4.25 3.66 3.88 4.75 4.42 6.13 6.27 6.69 2016 6.98 6.57 5.01 5.23 4.35 4.16 4.20 4.17 5.05 5.34 5.92 7.89 2017 6.47 6.35 6.12 4.79 4.76 4.31 4.04 4.68 4.50 5.95 6.68 7.14 2018 7.06 6.05 5.84 5.69 - - - - - - - - Average Over-Lake Cloud Cover (%) 2013 83.29 89.82 81.35 78.63 39.68 41.30 36.74 31.23 36.30 55.97 67.17 76.29 2014 74.32 58.18 49.23 56.63 45.32 44.93 40.19 42.58 41.00 64.77 77.63 74.26 2015 72.35 64.50 41.35 49.00 48.58 39.50 26.32 46.35 34.87 51.39 53.27 79.74 2016 75.19 70.86 61.29 54.83 39.10 34.67 33.35 35.81 42.60 58.26 48.10 77.71 2017 78.13 55.82 63.19 53.00 49.90 39.93 35.03 43.16 30.30 54.39 66.80 71.81 2018 63.87 58.93 41.42 45.43 - - - - - - - - Average Lake Surface Incident SW Radiation (w/m2) 2013 52.63 70.19 113.23 148.95 257.51 264.20 263.54 239.92 185.24 115.06 68.90 50.03 2014 60.33 106.02 163.73 193.24 245.67 255.44 254.74 218.90 177.87 102.65 61.31 51.58 2015 61.37 99.62 176.39 209.61 237.26 268.28 286.18 211.25 187.74 119.53 81.37 47.80 2016 59.13 92.63 145.34 198.19 259.50 279.88 270.54 231.89 176.97 111.04 86.05 48.88 2017 56.14 108.80 140.84 200.78 234.14 267.35 266.48 216.81 194.96 116.51 68.52 53.22 2018 67.92 105.36 177.12 217.48 - - - - - - - - Average Lake Surface Reflection (w/m2) 2013 -5.26 -7.02 -11.32 -14.89 -25.75 -26.42 -26.35 -23.99 -18.52 -11.51 -6.89 -5.00 2014 -7.85 -25.08 -41.21 -31.53 -24.57 -25.54 -25.47 -21.89 -17.79 -10.26 -6.13 -5.16 2015 -7.11 -18.79 -35.91 -22.24 -23.73 -26.83 -28.62 -21.13 -18.77 -11.95 -8.14 -4.78 2016 -5.91 -9.26 -14.53 -19.82 -25.95 -27.99 -27.05 -23.19 -17.70 -11.10 -8.61 -4.89 2017 -5.61 -10.88 -14.08 -20.08 -23.41 -26.73 -26.65 -21.68 -19.50 -11.65 -6.85 -5.32 2018 -6.79 -12.03 -17.71 -21.75 - - - - - - - - Average Lake Surface Net Long Wave Radiation (w/m2) 2013 -98.24 -91.06 -80.66 -62.50 -57.93 -50.19 -47.73 -51.58 -63.64 -73.56 -89.96 -108.18 2014 -107.59 -110.34 -94.61 -62.97 -52.90 -41.86 -48.93 -43.87 -63.25 -68.75 -92.76 -89.47 2015 -98.50 -111.96 -85.80 -65.36 -50.13 -48.79 -51.82 -44.70 -53.43 -74.14 -82.25 -77.50 2016 -102.13 -89.49 -73.35 -73.29 -64.01 -54.42 -43.29 -41.19 -51.41 -65.68 -81.87 -102.78 2017 -94.06 -88.79 -83.02 -64.53 -63.41 -48.81 -45.09 -49.83 -60.64 -68.16 -91.23 -107.96 2018 -102.21 -92.45 -91.63 -85.26 - - - - - - - - Average Lake Surface Latent Heat Flux (w/m2) 2013 -98.98 -62.82 -38.39 -17.85 -3.58 -9.23 -44.64 -38.71 -72.53 -76.76 -104.87 -110.24 2014 -85.50 -47.75 -27.16 -4.23 1.86 4.22 -14.75 -27.87 -60.78 -63.32 -105.72 -63.99 2015 -69.78 -60.76 -20.80 -4.94 2.03 -0.97 -24.13 -56.17 -46.06 -80.31 -68.67 -63.56 2016 -96.33 -56.45 -20.41 -25.89 -16.45 -26.47 -35.24 -49.22 -67.93 -64.03 -67.76 -133.19 2017 -78.34 -57.33 -43.56 -11.49 -23.90 -21.59 -31.22 -59.45 -53.05 -76.03 -98.43 -116.63 2018 -85.11 -42.02 -41.18 -36.32 - - - - - - - - Average Lake Surface Sensible Heat Flux (w/m2) 2013 -77.45 -53.28 -21.45 1.86 5.79 3.45 -1.82 -1.20 -8.47 -18.91 -47.78 -94.93 2014 -99.44 -51.12 -18.03 7.97 7.68 6.42 2.63 -0.51 -9.61 -13.94 -61.94 -44.52 2015 -69.67 -70.80 -7.36 7.28 7.79 4.57 1.54 -3.16 -3.85 -14.28 -21.97 -30.95 2016 -78.02 -40.77 -6.03 -5.10 2.55 1.51 -0.15 -2.93 -5.81 -14.47 -23.17 -92.71 2017 -64.68 -36.29 -21.87 4.65 0.89 2.37 -0.47 -4.95 -5.18 -15.84 -40.54 -89.05 2018 -74.82 -36.53 -15.35 -13.75 - - - - - - - - Average Lake Surface Net Surface Flux (w/m2) 2013 -228.19 -144.28 -38.67 55.48 176.00 181.59 141.45 123.13 19.75 -67.41 -182.13 -269.36 2014 -240.30 -128.23 -17.27 102.47 177.75 198.73 167.80 123.84 24.62 -54.96 -206.63 -152.11 2015 -183.92 -162.67 26.52 124.33 173.24 196.23 182.38 84.12 64.15 -63.04 -100.74 -129.73 2016 -224.11 -103.62 30.93 73.92 155.39 171.73 163.53 113.42 31.79 -45.86 -96.57 -286.36 2017 -187.25 -84.87 -21.88 109.22 123.91 171.96 161.95 78.79 54.94 -57.04 -170.09 -267.03 2018 -201.62 -77.71 11.09 60.21 - - - - - - - - Average Lake-Ice Surface Temperature (C) 2013 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2014 -4.19 -9.01 -4.39 -0.10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2015 -2.42 -10.04 -2.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2016 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2017 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2018 0.00 -2.57 0.00 0.00 - - - - - - - - Average Lake Ice Cover (%) 2013 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2014 7.20 38.87 43.42 17.40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2015 4.53 24.31 29.68 1.52 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2016 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2017 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2018 0.00 3.62 0.00 0.00 - - - - - - - - End-of-Month Lake Heat Storage (cal/10e17) 2013 214.90 166.73 152.48 172.35 237.42 302.39 354.63 400.14 407.09 382.15 316.99 217.40 2014 148.82 130.40 116.49 112.73 178.45 249.56 311.60 357.32 366.08 345.69 271.75 215.51 2015 150.78 127.38 112.28 145.12 209.17 279.38 346.81 377.93 400.82 377.46 341.39 293.42 2016 210.56 174.75 186.19 212.64 270.10 331.51 391.95 433.86 445.07 428.06 393.48 287.61 2017 218.38 190.05 181.98 221.05 266.85 328.34 388.21 417.20 436.82 415.65 354.80 256.07 2018 181.53 155.39 159.52 181.06 - - - - - - - - End-of-Month Basin Soil Moisture (cm) 2013 4.61 4.19 4.55 6.35 3.23 1.85 0.93 0.58 0.73 3.05 3.93 3.19 2014 2.80 2.58 3.74 5.65 2.80 1.68 0.91 1.23 1.47 3.05 3.99 3.80 2015 2.76 1.93 2.80 3.22 3.56 1.86 0.54 0.66 1.02 2.76 3.58 4.78 2016 4.65 3.86 5.91 4.07 2.06 1.09 0.62 0.66 1.49 2.17 2.97 3.12 2017 3.80 3.92 4.44 5.23 3.18 2.00 0.67 1.12 0.65 3.46 3.14 2.62 2018 3.07 3.94 3.21 3.67 - - - - - - - - End-of-Month Basin Groundwater Moisture (cm) 2013 5.49 5.70 5.71 6.83 6.37 5.83 5.32 4.94 4.64 4.62 5.20 5.28 2014 5.25 5.36 5.34 5.71 5.65 5.22 4.79 4.45 4.33 4.60 4.97 5.09 2015 5.02 4.82 4.86 5.07 4.93 4.78 4.49 4.18 4.01 3.97 4.23 4.79 2016 4.93 4.96 5.21 5.43 5.20 4.78 4.39 4.18 3.99 4.09 4.13 4.38 2017 4.78 4.92 5.28 5.39 5.46 5.00 4.57 4.24 3.98 4.56 5.07 4.89 2018 4.85 5.52 5.35 5.51 - - - - - - - - End-of-Month Basin Surface Moisture (cm) 2013 0.93 0.60 0.65 1.93 0.85 0.53 0.42 0.29 0.21 0.63 0.62 0.45 2014 0.43 0.52 0.65 1.15 0.63 0.40 0.23 0.33 0.32 0.55 0.82 0.64 2015 0.39 0.29 0.50 0.64 0.71 0.46 0.22 0.23 0.21 0.52 0.60 0.86 2016 0.57 0.52 1.09 0.71 0.50 0.35 0.24 0.34 0.41 0.57 0.59 0.54 2017 0.60 0.71 0.92 1.05 0.66 0.52 0.28 0.25 0.17 1.18 0.71 0.46 2018 0.49 1.12 0.57 0.86 - - - - - - - - End-of-Month Basin Snow Pack (cm) 2013 1.30 2.94 2.04 0.36 0.00 0.00 0.00 0.00 0.00 0.00 0.32 1.62 2014 2.94 3.86 2.28 0.31 0.00 0.00 0.00 0.00 0.00 0.01 1.08 1.80 2015 2.63 3.94 1.62 0.73 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.84 2016 0.93 0.91 0.14 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.49 2017 0.94 0.31 0.15 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 1.00 2018 0.71 0.78 0.88 0.12 - - - - - - - - End-of-Month Basin Total Moisture (cm) 2013 12.33 13.43 12.95 15.47 10.45 8.21 6.67 5.81 5.58 8.30 10.07 10.54 2014 11.42 12.32 12.01 12.82 9.08 7.30 5.93 6.01 6.12 8.21 10.86 11.33 2015 10.80 10.98 9.78 9.66 9.20 7.10 5.25 5.07 5.24 7.25 8.44 11.27 2016 11.08 10.25 12.35 10.21 7.76 6.22 5.25 5.18 5.89 6.83 7.69 8.53 2017 10.12 9.86 10.79 11.67 9.30 7.52 5.52 5.61 4.80 9.21 8.92 8.97 2018 9.12 11.36 10.01 10.16 - - - - - - - -