Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
008 UXUS97 KPUB 111220 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0620 MDT Sunday, August 11, 2024 This forecast is for the Air Force Academy for Sunday, August 11, 2024: If the trigger temperature of 73.0 F/22.8 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 798 ft/min (4.1 m/s) Maximum height of thermals.................. 20313 ft MSL (12690 ft AGL) Forecast maximum temperature................... 85.0 F/29.9 C Time of trigger temperature.................... 0930 MDT Time of overdevelopment........................ 1200 MDT Middle/high clouds during soaring window....... Broken/overcast opaque middle Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 16415 ft MSL (8792 ft AGL) Thermal soaring outlook for Monday 08/12....... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 06:09:56 / 19:58:49 MDT Total possible sunshine........... 13 hr 48 min 53 sec (828 min 53 sec) Altitude of sun at 13:04:22 MDT... 65.94 degrees Upper air data from numerical model forecast valid on 08/11/2024 at 0600 MDT Freezing level.................. 16335 ft MSL (8712 ft AGL) Convective condensation level... 16789 ft MSL (9166 ft AGL) Lifted condensation level....... 18071 ft MSL (10448 ft AGL) Lifted index.................... -3.1 K index......................... +20.4 Height Temperature Wind Wind Spd Lapse Rate ConvectionT Thermal Lift Rate ft MSL deg C deg F Dir kt m/s C/km F/kft deg C deg F Index fpm m/s -------------------------------------------------------------------------------- 50000 -65.0 -85.0 295 41 21 1.6 0.9 M M M M M 45000 -60.0 -76.0 290 57 29 6.3 3.5 M M M M M 40000 -50.2 -58.4 280 60 31 7.4 4.1 M M M M M 38000 -45.2 -49.4 275 57 29 7.4 4.1 M M M M M 36000 -40.8 -41.4 270 55 28 7.6 4.2 M M M M M 34000 -36.2 -33.2 270 53 27 7.7 4.2 M M M M M 32000 -31.5 -24.7 270 51 26 7.9 4.4 M M M M M 30000 -27.2 -17.0 270 49 25 7.3 4.0 42.0 107.5 9.8 M M 29000 -25.0 -13.0 275 47 24 7.3 4.0 41.1 106.0 9.2 M M 28000 -22.9 -9.2 275 46 24 5.6 3.1 40.2 104.3 8.6 M M 27000 -21.3 -6.3 275 43 22 5.4 3.0 38.4 101.1 7.2 M M 26000 -19.7 -3.5 280 41 21 5.5 3.0 36.8 98.2 5.9 M M 25000 -18.1 -0.6 280 38 20 5.8 3.2 35.4 95.7 4.8 M M 24000 -16.2 2.8 285 36 18 6.6 3.6 34.1 93.4 3.7 M M 23000 -14.3 6.3 290 34 17 6.7 3.6 33.0 91.4 2.8 M M 22000 -11.8 10.8 300 32 16 6.4 3.5 31.7 89.1 1.7 M M 21000 -9.9 14.2 310 32 17 6.4 3.5 30.5 86.9 0.6 M M 20000 -8.0 17.6 315 34 17 6.4 3.5 29.4 84.9 -0.4 1164 5.9 19500 -7.1 19.2 320 34 18 6.6 3.6 28.9 84.0 -0.9 1121 5.7 19000 -6.1 21.0 320 33 17 7.0 3.9 28.4 83.1 -1.3 1075 5.5 18500 -5.0 23.0 320 32 16 6.9 3.8 27.9 82.3 -1.7 1029 5.2 18000 -3.9 25.0 320 30 15 8.6 4.7 27.6 81.6 -2.1 982 5.0 17500 -2.7 27.1 315 26 13 8.9 4.9 27.4 81.3 -2.3 930 4.7 17000 -1.4 29.5 310 22 11 8.6 4.7 27.3 81.1 -2.6 878 4.5 16500 -0.3 31.5 305 18 9 7.7 4.2 27.0 80.5 -2.9 830 4.2 16000 0.8 33.4 295 15 8 7.8 4.3 26.6 79.9 -3.3 782 4.0 15500 1.8 35.2 285 12 6 6.6 3.6 26.2 79.2 -3.8 736 3.7 15000 2.8 37.0 275 11 5 6.7 3.7 25.7 78.3 -4.3 693 3.5 14500 3.8 38.8 260 9 5 7.4 4.1 25.3 77.5 -4.8 648 3.3 14000 4.9 40.8 260 8 4 7.7 4.2 24.9 76.9 -5.1 600 3.0 13500 6.0 42.8 255 7 3 7.9 4.4 24.6 76.3 -5.5 551 2.8 13000 7.2 45.0 265 6 3 8.3 4.6 24.4 75.9 -5.8 500 2.5 12500 8.5 47.3 270 5 3 8.8 4.8 24.2 75.6 -6.0 447 2.3 12000 9.8 49.6 280 5 2 8.9 4.9 24.0 75.3 -6.2 394 2.0 11750 10.4 50.7 290 5 2 8.4 4.6 24.0 75.2 -6.3 367 1.9 11500 11.0 51.8 295 5 2 7.2 3.9 23.8 74.9 -6.4 342 1.7 11250 11.5 52.7 300 5 3 7.7 4.2 23.6 74.5 -6.7 319 1.6 11000 12.2 54.0 300 5 3 8.4 4.6 23.5 74.3 -6.8 293 1.5 10750 12.8 55.0 305 5 3 8.5 4.7 23.4 74.1 -6.9 267 1.4 10500 13.4 56.1 310 6 3 7.6 4.2 23.3 73.9 -7.1 241 1.2 10250 13.9 57.0 310 6 3 7.1 3.9 23.1 73.5 -7.3 219 1.1 10000 14.4 57.9 305 6 3 7.7 4.2 22.9 73.2 -7.5 195 1.0 9750 15.0 59.0 305 7 3 7.6 4.2 22.7 72.9 -7.7 171 0.9 9500 15.5 59.9 305 7 4 7.6 4.2 22.6 72.7 -7.9 147 0.7 9250 16.1 61.0 305 7 4 6.1 3.4 22.4 72.3 -8.1 124 0.6 9000 16.4 61.5 305 8 4 4.7 2.6 22.0 71.7 -8.5 106 0.5 8750 16.7 62.1 300 9 5 5.5 3.0 21.7 71.0 -8.9 89 0.5 8500 17.1 62.8 300 10 5 2.9 1.6 21.3 70.4 -9.4 72 0.4 8250 17.0 62.6 295 11 6 -4.4 -2.4 20.5 68.9 -10.2 67 0.3 8000 16.2 61.2 290 11 6 -17.6 -9.7 19.0 66.2 -11.8 84 0.4 7750 14.2 57.6 285 9 4 -31.5 -17.3 16.4 61.5 -14.5 137 0.7 7500 M M M M M M M M M M M M 7250 M M M M M M M M M M M M 7000 M M M M M M M M M M M M 6750 M M M M M M M M M M M M * * * * * * Numerical weather prediction model forecast data valid * * * * * * 08/11/2024 at 0900 MDT | 08/11/2024 at 1200 MDT | CAPE... +504.8 LI... -2.5 | CAPE... +769.2 LI... -3.3 CINH... -55.2 K Index... +22.7 | CINH... -0.6 K Index... +27.6 | Height Temperature Wnd WndSpd Lapse Rate | Temperature Wnd WndSpd Lapse Rate ft MSL deg C deg F Dir kt m/s C/km F/kft | deg C deg F Dir kt m/s C/km F/kft -------------------------------------------------------------------------------- 50000 -64.7 -84.5 285 38 19 1.3 0.7 | -64.9 -84.8 280 34 17 1.1 0.6 45000 -59.7 -75.5 280 51 26 6.8 3.8 | -60.1 -76.2 275 50 26 7.0 3.8 40000 -49.4 -56.9 275 57 29 6.9 3.8 | -49.6 -57.3 270 57 29 6.9 3.8 38000 -44.8 -48.6 270 54 28 6.9 3.8 | -45.0 -49.0 270 54 28 6.9 3.8 36000 -40.6 -41.1 270 52 27 7.7 4.2 | -40.8 -41.4 265 52 27 8.2 4.5 34000 -35.8 -32.4 265 51 26 8.0 4.4 | -35.6 -32.1 265 51 26 8.6 4.7 32000 -31.0 -23.8 265 50 26 8.0 4.4 | -30.5 -22.9 270 49 25 8.2 4.5 30000 -26.5 -15.7 270 50 26 7.5 4.1 | -26.8 -16.2 270 48 25 6.2 3.4 29000 -24.3 -11.7 270 49 25 7.5 4.1 | -24.9 -12.8 275 47 24 6.3 3.5 28000 -22.2 -8.0 270 49 25 5.0 2.7 | -23.2 -9.8 275 46 24 5.1 2.8 27000 -20.8 -5.4 275 46 24 4.8 2.7 | -21.7 -7.1 280 44 23 5.0 2.7 26000 -19.3 -2.7 275 44 22 4.9 2.7 | -20.2 -4.4 280 42 21 5.0 2.8 25000 -17.9 -0.2 280 41 21 5.1 2.8 | -18.7 -1.7 285 39 20 5.4 3.0 24000 -16.2 2.8 285 38 20 5.6 3.1 | -16.7 1.9 285 36 19 6.8 3.7 23000 -14.5 5.9 290 35 18 5.6 3.1 | -14.1 6.6 290 33 17 6.8 3.7 22000 -12.3 9.9 300 32 16 6.9 3.8 | -12.1 10.2 295 30 16 7.7 4.2 21000 -10.3 13.5 305 30 15 7.1 3.9 | -9.8 14.4 295 29 15 7.8 4.3 20000 -8.3 17.1 310 27 14 7.4 4.0 | -7.6 18.3 295 27 14 7.9 4.3 19500 -7.3 18.9 310 26 14 7.8 4.3 | -6.5 20.3 295 27 14 7.2 3.9 19000 -6.1 21.0 310 26 13 8.2 4.5 | -5.6 21.9 295 24 12 6.0 3.3 18500 -4.9 23.2 315 25 13 8.2 4.5 | -4.7 23.5 290 20 10 5.9 3.2 18000 -3.7 25.3 315 23 12 8.1 4.5 | -3.7 25.3 285 17 9 7.4 4.1 17500 -2.5 27.5 315 20 11 8.1 4.5 | -2.7 27.1 285 15 8 7.4 4.1 17000 -1.3 29.7 315 18 9 8.2 4.5 | -1.6 29.1 280 12 6 7.7 4.2 16500 -0.1 31.8 315 17 9 8.3 4.5 | -0.5 31.1 290 13 7 8.0 4.4 16000 1.2 34.2 310 16 8 8.3 4.6 | 0.6 33.1 295 14 7 8.0 4.4 15500 2.3 36.1 310 16 8 7.7 4.2 | 1.8 35.2 300 16 8 8.4 4.6 15000 3.4 38.1 305 16 8 7.7 4.2 | 3.1 37.6 305 17 9 8.4 4.6 14500 4.6 40.3 300 16 8 8.1 4.4 | 4.3 39.7 305 18 9 8.6 4.7 14000 5.7 42.3 295 16 8 8.1 4.5 | 5.5 41.9 305 20 10 8.7 4.7 13500 6.9 44.4 295 16 8 7.6 4.2 | 6.8 44.2 305 21 11 8.2 4.5 13000 7.9 46.2 295 16 8 7.5 4.1 | 7.8 46.0 310 20 10 8.1 4.4 12500 9.2 48.6 295 16 8 9.0 4.9 | 8.9 48.0 310 19 10 9.3 5.1 12000 10.4 50.7 300 16 8 8.2 4.5 | 10.4 50.7 310 17 9 10.8 5.9 11750 11.0 51.8 300 16 8 7.7 4.2 | 11.1 52.0 305 16 8 9.7 5.3 11500 11.5 52.7 300 16 8 6.9 3.8 | 11.8 53.2 305 16 8 8.8 4.8 11250 12.0 53.6 305 16 8 7.4 4.0 | 12.5 54.5 305 16 8 9.8 5.4 11000 12.5 54.5 305 16 8 7.7 4.2 | 13.2 55.8 305 15 8 10.2 5.6 10750 13.1 55.6 305 16 8 7.8 4.3 | 14.0 57.2 305 15 8 10.3 5.6 10500 13.6 56.5 305 16 8 7.1 3.9 | 14.7 58.5 305 15 8 9.4 5.2 10250 14.1 57.4 305 15 8 7.2 3.9 | 15.4 59.7 305 15 8 9.3 5.1 10000 14.7 58.5 305 15 8 7.9 4.3 | 16.1 61.0 310 15 8 10.1 5.5 9750 15.2 59.4 305 15 7 7.8 4.3 | 16.9 62.4 310 15 7 10.1 5.5 9500 15.8 60.4 305 14 7 7.4 4.1 | 17.6 63.7 310 14 7 9.3 5.1 9250 16.3 61.3 300 13 7 7.4 4.1 | 18.3 64.9 310 14 7 9.5 5.2 9000 16.9 62.4 300 13 7 7.9 4.3 | 19.1 66.4 310 14 7 10.7 5.8 8750 17.5 63.5 300 13 7 8.4 4.6 | 19.9 67.8 310 14 7 10.5 5.7 8500 18.0 64.4 300 14 7 6.5 3.6 | 20.6 69.1 310 14 7 10.7 5.9 8250 18.3 64.9 295 14 7 4.2 2.3 | 21.5 70.7 310 14 7 12.2 6.7 8000 18.6 65.5 290 12 6 8.5 4.7 | 22.6 72.7 310 13 7 18.4 10.1 7750 19.4 66.9 280 9 5 14.7 8.0 | 24.2 75.6 310 12 6 25.8 14.2 7500 M M M M M M M | M M M M M M M 7250 M M M M M M M | M M M M M M M 7000 M M M M M M M | M M M M M M M 6750 M M M M M M M | M M M M M M M 08/11/2024 at 1500 MDT | 08/11/2024 at 1800 MDT | CAPE... +913.2 LI... -4.8 | CAPE... +465.9 LI... -2.8 CINH... -0.2 K Index... +30.7 | CINH... -28.4 K Index... +18.7 | Height Temperature Wnd WndSpd Lapse Rate | Temperature Wnd WndSpd Lapse Rate ft MSL deg C deg F Dir kt m/s C/km F/kft | deg C deg F Dir kt m/s C/km F/kft -------------------------------------------------------------------------------- 50000 -64.6 -84.3 280 31 16 1.2 0.7 | -64.6 -84.3 275 31 16 1.2 0.7 45000 -59.8 -75.6 275 47 24 6.7 3.7 | -59.5 -75.1 275 45 23 7.1 3.9 40000 -49.2 -56.6 270 53 27 7.0 3.9 | -48.5 -55.3 270 51 26 6.7 3.7 38000 -44.9 -48.8 265 54 28 7.0 3.9 | -44.5 -48.1 270 55 29 6.7 3.7 36000 -40.7 -41.3 265 55 29 7.8 4.3 | -40.5 -40.9 270 60 31 7.1 3.9 34000 -35.8 -32.4 265 55 28 8.1 4.4 | -36.1 -33.0 270 58 30 7.3 4.0 32000 -31.0 -23.8 270 55 28 8.2 4.5 | -31.7 -25.1 270 56 29 7.6 4.2 30000 -27.4 -17.3 270 52 27 6.0 3.3 | -27.9 -18.2 270 52 27 6.3 3.5 29000 -25.6 -14.1 270 50 26 6.0 3.3 | -26.1 -15.0 270 49 25 6.4 3.5 28000 -23.8 -10.8 270 48 25 5.7 3.1 | -24.2 -11.6 270 47 24 6.7 3.7 27000 -22.1 -7.8 275 46 24 5.7 3.1 | -22.2 -8.0 275 46 23 6.7 3.7 26000 -20.5 -4.9 280 44 23 5.7 3.1 | -20.2 -4.4 280 44 23 6.7 3.7 25000 -18.8 -1.8 280 42 22 5.8 3.2 | -18.2 -0.8 285 44 22 6.7 3.7 24000 -16.6 2.1 285 37 19 6.1 3.4 | -15.7 3.7 290 40 21 6.7 3.7 23000 -14.8 5.4 290 34 17 6.1 3.4 | -13.7 7.3 290 37 19 6.7 3.7 22000 -12.9 8.8 290 30 15 7.3 4.0 | -11.7 10.9 295 34 17 6.9 3.8 21000 -10.8 12.6 295 26 13 7.4 4.1 | -9.7 14.5 295 30 15 7.0 3.8 20000 -8.6 16.5 295 23 12 7.5 4.1 | -7.7 18.1 300 25 13 7.0 3.9 19500 -7.6 18.3 300 21 11 7.9 4.3 | -6.7 19.9 300 23 12 7.4 4.1 19000 -6.3 20.7 290 20 10 8.4 4.6 | -5.5 22.1 300 20 10 7.9 4.3 18500 -5.1 22.8 285 19 10 8.4 4.6 | -4.4 24.1 295 17 9 7.8 4.3 18000 -3.8 25.2 280 19 10 8.6 4.7 | -3.1 26.4 285 16 8 9.2 5.0 17500 -2.5 27.5 280 20 10 8.6 4.7 | -1.8 28.8 280 16 8 9.2 5.0 17000 -1.3 29.7 280 20 10 8.4 4.6 | -0.5 31.1 275 16 8 9.0 5.0 16500 -0.1 31.8 280 20 10 8.2 4.5 | 0.9 33.6 280 16 8 8.9 4.9 16000 1.0 33.8 285 20 10 8.3 4.5 | 2.2 36.0 290 17 9 8.9 4.9 15500 2.2 36.0 285 19 10 8.8 4.9 | 3.5 38.3 290 15 8 8.4 4.6 15000 3.4 38.1 285 16 8 8.9 4.9 | 4.7 40.5 290 13 7 8.5 4.6 14500 4.6 40.3 285 14 7 9.5 5.2 | 6.0 42.8 285 10 5 8.4 4.6 14000 6.0 42.8 285 13 7 9.6 5.2 | 7.2 45.0 285 9 5 8.4 4.6 13500 7.4 45.3 290 12 6 10.0 5.5 | 8.4 47.1 280 8 4 8.7 4.8 13000 9.0 48.2 290 12 6 9.9 5.4 | 9.8 49.6 285 8 4 8.8 4.8 12500 10.3 50.5 290 11 6 9.7 5.3 | 11.0 51.8 290 9 4 8.6 4.7 12000 11.9 53.4 290 11 6 11.5 6.3 | 12.4 54.3 290 9 5 9.8 5.4 11750 12.8 55.0 290 11 5 9.6 5.3 | 13.1 55.6 290 9 5 8.5 4.6 11500 13.4 56.1 295 10 5 7.8 4.3 | 13.6 56.5 295 9 5 7.1 3.9 11250 14.0 57.2 295 10 5 9.6 5.3 | 14.1 57.4 295 9 5 8.6 4.7 11000 14.8 58.6 295 10 5 10.2 5.6 | 14.8 58.6 290 9 5 9.2 5.0 10750 15.5 59.9 295 10 5 10.6 5.8 | 15.4 59.7 290 9 5 9.7 5.3 10500 16.3 61.3 295 10 5 8.4 4.6 | 16.0 60.8 290 9 5 7.5 4.1 10250 16.8 62.2 295 10 5 8.3 4.6 | 16.4 61.5 285 9 5 7.6 4.2 10000 17.6 63.7 295 9 5 10.5 5.8 | 17.1 62.8 285 9 4 10.0 5.5 9750 18.3 64.9 295 9 5 10.1 5.5 | 17.7 63.9 285 8 4 9.6 5.3 9500 19.1 66.4 300 9 5 9.6 5.3 | 18.4 65.1 285 8 4 8.9 4.9 9250 19.8 67.6 300 9 4 10.0 5.5 | 19.0 66.2 290 7 4 9.0 5.0 9000 20.6 69.1 300 8 4 11.0 6.0 | 19.7 67.5 290 7 4 10.3 5.7 8750 21.4 70.5 300 8 4 10.9 6.0 | 20.5 68.9 290 7 3 10.2 5.6 8500 23.0 73.4 300 8 4 11.2 6.2 | 21.2 70.2 295 6 3 10.2 5.6 8250 24.0 75.2 300 7 4 17.4 9.5 | 22.0 71.6 295 6 3 10.1 5.6 8000 25.5 77.9 305 7 3 24.9 13.7 | 22.7 72.9 300 5 3 10.3 5.7 7750 27.1 80.8 305 6 3 12.5 6.9 | 24.2 75.6 310 3 2 10.2 5.6 7500 M M M M M M M | M M M M M M M 7250 M M M M M M M | M M M M M M M 7000 M M M M M M M | M M M M M M M 6750 M M M M M M M | M M M M M M M ________________________________________________________________________________ This product is issued twice per day, once by approximately 0630 MST/0730 MDT (1330 UTC). It is not continuously monitored nor updated after its initial issuance. The information contained herein is based on rawinsonde observation and/or numerical weather prediction model data taken near the Air Force Academy in Colorado Springs, Colorado at North Latitude: 38 deg 58 min 48.000 sec West Longitude: 104 deg 49 min 12.000 sec Elevation: 6572 feet (2003 meters) and may not be representative of other areas along the Front Range of the Colorado Rocky Mountains. Note that some elevations in numerical weather prediction models differ from actual station elevations, which can lead to data which appear to be below ground. Erroneous data such as these should not be used. The content and format of this report as well as the issuance times are subject to change without prior notice. Comments and suggestions are welcome and should be directed to one of the addresses or phone numbers shown at the bottom of this page. To expedite a response to comments, be sure to mention your interest in the soaring forecast. DEFINITIONS: CAPE (Convective Available Potential Energy) - An integrated measure of the energy available for convective development, also known as the positive area on a thermodynamic diagram. Units are Joules per kilogram. Larger values are indicative of greater instability and the possibility of stronger convective activity, including thunderstorms. Values around or greater than 1000 suggest the possibility of severe weather should convective activity develop. CIN (Convective Inhibition) - An integrated measure of the amount of energy needed to initiate convective activity, also known as the negative area on a thermodynamic diagram. Units are Joules per kilogram. The more negative this number, the more energy is required to initiate convection. This inhibitive energy can be overcome through surface heating, cooling aloft, lifting mechanisms (orographic, frontal, gravity waves, etc.) Convective Condensation Level - The height to which an air parcel possessing the average saturation mixing ratio in the lowest 4000 feet of the airmass, if heated sufficiently from below, will rise dry adiabatically until it just becomes saturated. It estimates the base of cumulus clouds that are produced by surface heating only. Convection Temperature (ConvectionT) - The surface temperature required to make the airmass dry adiabatic up to the given level. It can be considered a "trigger temperature" for that level. Freezing Level - The height where the temperature is zero degrees Celsius. Height of Stable Layer - The height (between 12,000 and 18,000 feet above mean sea level) where the smallest lapse rate exists. The location and existence of this feature is important in the generation of mountain waves. K Index - A measure of stability which combines the temperature difference between approximately 5,000 and 18,000 feet above the surface, the amount of moisture at approximately 5,000 feet above the surface, and a measure of the dryness at approximately 10,000 feet above the surface. Larger positive numbers indicate more instability and a greater likelihood of thunderstorm development. One interpretation of K index values regarding soaring in the western United States is given in WMO Technical Note 158 and is reproduced in the following table: below -10 no or weak thermals -10 to 5 dry thermals or 1/8 cumulus with moderate thermals 5 to 15 good soaring conditions 15 to 20 good soaring conditions with occasional showers 20 to 30 excellent soaring conditions, but increasing probability of showers and thunderstorms above 30 more than 60 percent probability of thunderstorms Lapse Rate - The change with height of the temperature. Negative values indicate inversions. Lifted Condensation Level - The height to which an air parcel possessing the average dew point in the lowest 4000 feet of the airmass and the forecast maximum temperature must be lifted dry adiabatically to attain saturation. Lifted Index (LI) - The difference between the environmental temperature at a level approximately 18,000 feet above the surface and the temperature of an air parcel lifted dry adiabatically from the surface to its lifted condensation level and then pseudoadiabatically thereafter to this same level. The parcel`s initial temperature is the forecast maximum temperature and its dew point is the average dew point in the lowest 4000 feet of the airmass. Negative values are indicative of instability with positive values showing stable conditions. Lift Rate - An experimental estimate of the strength of thermals. It is computed the same way as the maximum rate of lift but uses the actual level rather than the maximum height of thermals in the calculation. Also, none of the empirical adjustments based on cloudiness and K-index are applied to these calculations. Maximum Height of Thermals - The height where the dry adiabat through the forecast maximum temperature intersects the environmental temperature. Maximum Rate of Lift - An estimate of the maximum strength of thermals. It is computed from an empirical formula which combines the expected maximum height of thermals with the difference in the environmental temperatures between the maximum height of thermals and the temperature 4,000 feet above the ground. After this computation, further empirical adjustments are made based on the value of the K-index and the amount and opacity of middle and high level cloudiness expected between the time of trigger temperature and the time of overdevelopment. Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus) or high (cirrus, cirrostratus, cirrocumulus) clouds. Broken means that between 60% and 90% of the sky is covered by the cloud, with overcast conditions occurring when more than 90% of the sky is covered by the cloud. Thin implies that the clouds are predominantly transparent, meaning that some sunlight is reaching the ground, in contrast to opaque which suggests that little sunlight is reaching the ground. Potential Height of Wave - The minimum of the following two heights: 1. Level above the height of stable layer (or 14,000 feet if none exists) where the wind direction changes by 30 degrees or more 2. Level above the height of stable layer (or 14,000 feet if none exists) where the wind speed no longer increases with height PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA) on the 500 millibar isobaric surface (approximately 18,000 feet above mean sea level). Weak PVA has been shown to assist in mountain wave soaring. Soaring Window - The time between the time the trigger temperature is reached and the time of overdevelopment. Thermal Index - The difference between the environmental temperature and the temperature at a particular level determined by following the dry adiabat through the forecast maximum temperature up to that level. Negative values are indicative of thermal lift. Thermal Soaring Index - An adjective rating (for sailplanes) based on the computed maximum rate of lift, and the wind speed and middle and high cloud cover expected during the soaring window (the time of the trigger temperature and the time of overdevelopment) according to the following: Maximum rate of lift Adjective Rating >= 800 fpm Excellent >= 400 and < 800 fpm Good >= 200 and < 400 fpm Fair < 200 fpm Poor Time of Overdevelopment - The time one or more of the following phenomena, which essentially shut off thermal lift, is expected to occur: 1. formation of broken to overcast convective cloud cover 2. formation of scattered to numerous downbursts 3. initiation of widespread precipitation Time of Trigger Temperature - The time the surface temperature is expected to reach the trigger temperature. Trigger Temperature - The surface temperature required to make the first 4000 feet of the atmosphere dry adiabatic. Wave Soaring Index - An empirical, adjective rating (for sailplanes) which attempts to combine a variety of phenomena important in mountain wave soaring into a single index number. Objective points are assigned to these phenomena: wind speed and direction at 14,000 ft MSL, the static stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above the stable layer, jet stream location and frontal and upper trough movements. 042613