Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
507 UXUS97 KPUB 121219 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0619 MDT Friday, July 12, 2024 This forecast is for the Air Force Academy for Friday, July 12, 2024: If the trigger temperature of 80.6 F/27.0 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 2127 ft/min (10.8 m/s) Maximum height of thermals.................. 28386 ft MSL (20768 ft AGL) Forecast maximum temperature................... 96.0 F/36.0 C Time of trigger temperature.................... 0830 MDT Time of overdevelopment........................ None Middle/high clouds during soaring window....... None Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 24400 ft MSL (16782 ft AGL) Thermal soaring outlook for Saturday 07/13..... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:44:34 / 20:25:32 MDT Total possible sunshine........... 14 hr 40 min 58 sec (880 min 58 sec) Altitude of sun at 13:05:03 MDT... 72.80 degrees Upper air data from numerical model forecast valid on 07/12/2024 at 0600 MDT Freezing level.................. 16933 ft MSL (9315 ft AGL) Convective condensation level... 18840 ft MSL (11222 ft AGL) Lifted condensation level....... 21870 ft MSL (14252 ft AGL) Lifted index.................... -6.5 K index......................... +22.6 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 -60.0 -76.0 350 13 7 2.7 1.5 M M M M M 45000 -56.4 -69.5 345 22 11 1.8 1.0 M M M M M 40000 -52.7 -62.9 340 32 17 5.7 3.1 M M M M M 38000 -49.3 -56.7 345 30 16 5.7 3.1 M M M M M 36000 -45.9 -50.6 345 28 15 6.3 3.5 M M M M M 34000 -41.2 -42.2 345 27 14 8.0 4.4 M M M M M 32000 -36.4 -33.5 345 25 13 8.2 4.5 M M M M M 30000 -31.6 -24.9 345 25 13 8.0 4.4 36.5 97.8 0.8 M M 29000 -29.2 -20.6 345 24 13 8.0 4.4 35.9 96.7 0.3 M M 28000 -26.8 -16.2 345 24 13 7.7 4.2 35.4 95.6 -0.2 2098 10.7 27000 -24.5 -12.1 345 25 13 7.6 4.2 34.5 94.0 -0.9 2000 10.2 26000 -22.2 -8.0 350 26 13 7.6 4.2 33.7 92.6 -1.6 1902 9.7 25000 -19.4 -2.9 350 26 13 6.6 3.6 32.8 91.0 -2.4 1781 9.0 24000 -17.5 0.5 350 24 12 6.5 3.6 31.5 88.7 -3.6 1695 8.6 23000 -15.7 3.7 345 22 11 6.6 3.6 30.4 86.7 -4.7 1609 8.2 22000 -13.6 7.5 340 21 11 9.0 4.9 29.5 85.1 -5.6 1518 7.7 21000 -11.0 12.2 345 20 10 8.9 4.9 29.1 84.5 -6.0 1410 7.2 20000 -8.4 16.9 345 20 10 8.9 4.9 28.9 84.0 -6.4 1303 6.6 19500 -7.1 19.2 350 20 10 9.0 5.0 28.8 83.8 -6.6 1249 6.3 19000 -5.8 21.6 350 20 10 9.1 5.0 28.7 83.6 -6.7 1193 6.1 18500 -4.4 24.1 350 20 10 9.1 5.0 28.6 83.4 -6.8 1137 5.8 18000 -3.0 26.6 350 19 10 9.4 5.2 28.5 83.3 -6.9 1080 5.5 17500 -1.6 29.1 350 19 10 9.4 5.2 28.4 83.2 -7.0 1023 5.2 17000 -0.2 31.6 350 18 9 9.4 5.1 28.4 83.1 -7.1 966 4.9 16500 1.2 34.2 350 18 9 9.4 5.1 28.3 83.0 -7.2 910 4.6 16000 2.6 36.7 350 17 9 9.4 5.1 28.3 82.9 -7.3 853 4.3 15500 4.0 39.2 345 16 8 9.3 5.1 28.2 82.7 -7.4 797 4.0 15000 5.4 41.7 345 15 8 9.3 5.1 28.1 82.6 -7.5 740 3.8 14500 6.8 44.2 340 15 8 9.3 5.1 28.1 82.5 -7.6 684 3.5 14000 8.2 46.8 335 15 8 9.3 5.1 28.0 82.4 -7.8 627 3.2 13500 9.6 49.3 330 15 8 9.2 5.1 27.9 82.3 -7.9 571 2.9 13000 10.9 51.6 325 14 7 9.4 5.1 27.8 82.1 -8.0 516 2.6 12500 12.4 54.3 325 14 7 9.9 5.4 27.8 82.1 -8.1 457 2.3 12000 13.8 56.8 320 14 7 10.2 5.6 27.8 82.1 -8.1 398 2.0 11750 14.6 58.3 315 14 7 8.9 4.9 27.9 82.2 -8.1 368 1.9 11500 15.2 59.4 315 15 8 7.3 4.0 27.7 81.9 -8.3 343 1.7 11250 15.7 60.3 310 15 8 8.1 4.4 27.5 81.6 -8.5 319 1.6 11000 16.3 61.3 310 15 8 8.3 4.5 27.4 81.4 -8.6 294 1.5 10750 16.9 62.4 305 15 8 8.8 4.8 27.3 81.2 -8.8 269 1.4 10500 17.5 63.5 300 15 8 6.5 3.6 27.2 81.0 -8.9 243 1.2 10250 17.9 64.2 295 16 8 5.8 3.2 26.9 80.4 -9.4 226 1.1 10000 18.4 65.1 290 16 8 7.5 4.1 26.7 80.0 -9.6 203 1.0 9750 18.9 66.0 285 16 8 7.0 3.8 26.5 79.6 -9.9 181 0.9 9500 19.4 66.9 280 16 8 7.5 4.1 26.3 79.3 -10.1 158 0.8 9250 19.9 67.8 280 17 9 6.7 3.7 26.1 79.0 -10.3 134 0.7 9000 20.3 68.5 275 18 9 5.4 2.9 25.8 78.4 -10.7 115 0.6 8750 20.7 69.3 275 19 10 5.8 3.2 25.5 77.8 -11.0 96 0.5 8500 21.1 70.0 270 20 10 4.4 2.4 25.1 77.3 -11.4 77 0.4 8250 21.3 70.3 270 20 10 0.2 0.1 24.6 76.2 -12.0 64 0.3 8000 20.8 69.4 270 18 9 -19.2 -10.5 23.3 74.0 -13.3 72 0.4 7750 18.2 64.8 270 13 7 -46.4 -25.4 20.0 68.0 -16.6 142 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 * * * * * * 07/12/2024 at 0900 MDT | 07/12/2024 at 1200 MDT | CAPE... +886.4 LI... -2.0 | CAPE... +70.7 LI... -0.7 CINH... -32.9 K Index... +21.5 | CINH... -0.3 K Index... +15.4 | 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 -60.5 -76.9 015 10 5 2.3 1.3 | -60.3 -76.5 350 4 2 1.9 1.1 45000 -57.1 -70.8 005 17 9 2.2 1.2 | -56.9 -70.4 340 13 7 2.5 1.4 40000 -52.8 -63.0 345 31 16 5.9 3.2 | -52.6 -62.7 355 29 15 5.5 3.0 38000 -49.3 -56.7 345 29 15 5.9 3.2 | -49.3 -56.7 350 27 14 5.5 3.0 36000 -45.7 -50.3 345 28 14 6.7 3.7 | -46.0 -50.8 345 26 13 5.8 3.2 34000 -40.9 -41.6 345 27 14 8.1 4.5 | -40.6 -41.1 345 26 13 8.3 4.5 32000 -36.0 -32.8 345 27 14 8.2 4.5 | -35.6 -32.1 345 26 13 8.2 4.5 30000 -31.4 -24.5 345 26 13 7.5 4.1 | -31.1 -24.0 340 24 12 7.6 4.2 29000 -29.2 -20.6 345 25 13 7.5 4.1 | -28.8 -19.8 340 24 12 7.6 4.2 28000 -26.9 -16.4 345 24 13 7.8 4.3 | -26.5 -15.7 340 22 12 7.8 4.3 27000 -24.5 -12.1 345 23 12 7.8 4.3 | -24.1 -11.4 340 21 11 7.8 4.3 26000 -22.2 -8.0 345 22 12 7.8 4.3 | -21.8 -7.2 340 19 10 7.8 4.3 25000 -19.3 -2.7 345 21 11 6.4 3.5 | -19.5 -3.1 340 17 9 7.2 4.0 24000 -17.4 0.7 345 21 11 6.4 3.5 | -17.4 0.7 340 17 9 6.8 3.7 23000 -15.5 4.1 340 20 10 6.5 3.6 | -15.4 4.3 335 18 9 6.8 3.8 22000 -13.5 7.7 335 20 10 8.4 4.6 | -13.3 8.1 335 18 9 7.4 4.1 21000 -11.1 12.0 335 18 9 8.3 4.6 | -10.5 13.1 325 20 10 7.8 4.3 20000 -8.7 16.3 330 17 9 8.5 4.7 | -8.3 17.1 320 23 12 8.0 4.4 19500 -7.5 18.5 330 16 8 9.3 5.1 | -7.1 19.2 315 23 12 9.3 5.1 19000 -6.1 21.0 330 16 8 9.7 5.3 | -5.7 21.7 320 24 12 9.5 5.2 18500 -4.6 23.7 330 16 8 9.7 5.3 | -4.3 24.3 320 24 13 9.5 5.2 18000 -3.2 26.2 335 16 8 9.9 5.4 | -2.9 26.8 320 24 12 9.4 5.2 17500 -1.7 28.9 335 16 8 9.9 5.4 | -1.5 29.3 320 23 12 9.4 5.2 17000 -0.3 31.5 335 15 8 9.6 5.3 | -0.1 31.8 320 22 11 9.5 5.2 16500 1.2 34.2 335 15 8 9.5 5.2 | 1.3 34.3 325 21 11 9.6 5.3 16000 2.6 36.7 335 15 8 9.5 5.2 | 2.7 36.9 325 20 10 9.6 5.2 15500 4.0 39.2 335 16 8 9.6 5.3 | 4.1 39.4 325 19 10 9.5 5.2 15000 5.4 41.7 335 16 8 9.6 5.3 | 5.5 41.9 330 18 9 9.5 5.2 14500 6.8 44.2 335 16 8 9.4 5.2 | 6.9 44.4 330 18 9 10.0 5.5 14000 8.2 46.8 335 16 8 9.5 5.2 | 8.4 47.1 330 17 9 10.0 5.5 13500 9.6 49.3 335 16 8 9.2 5.0 | 9.9 49.8 330 17 9 9.6 5.3 13000 11.0 51.8 335 16 8 9.2 5.0 | 11.3 52.3 330 17 9 10.1 5.6 12500 12.4 54.3 330 16 8 9.6 5.3 | 12.9 55.2 330 17 9 10.5 5.8 12000 13.8 56.8 330 16 8 9.9 5.5 | 14.4 57.9 330 17 9 10.6 5.8 11750 14.6 58.3 330 16 8 9.1 5.0 | 15.2 59.4 330 17 9 9.1 5.0 11500 15.2 59.4 330 16 8 8.4 4.6 | 15.8 60.4 330 17 9 8.7 4.8 11250 15.8 60.4 330 16 8 8.8 4.8 | 16.5 61.7 330 17 9 9.9 5.5 11000 16.5 61.7 325 16 8 8.9 4.9 | 17.3 63.1 330 16 8 9.8 5.4 10750 17.2 63.0 325 16 8 8.5 4.7 | 18.0 64.4 335 16 8 9.3 5.1 10500 17.8 64.0 325 17 9 10.2 5.6 | 18.7 65.7 335 16 8 11.3 6.2 10250 18.6 65.5 325 16 8 9.6 5.3 | 19.6 67.3 335 16 8 11.3 6.2 10000 19.2 66.6 325 16 8 7.5 4.1 | 20.3 68.5 335 16 8 9.2 5.1 9750 19.8 67.6 325 15 8 7.9 4.3 | 21.0 69.8 335 16 8 9.7 5.3 9500 20.4 68.7 325 15 8 8.6 4.7 | 21.8 71.2 335 16 8 9.8 5.4 9250 21.1 70.0 330 14 7 8.7 4.8 | 22.5 72.5 335 16 8 10.1 5.5 9000 21.6 70.9 325 14 7 7.9 4.3 | 23.3 73.9 335 16 8 10.2 5.6 8750 22.2 72.0 325 14 7 8.0 4.4 | 24.0 75.2 335 16 8 9.8 5.4 8500 22.7 72.9 325 13 7 8.2 4.5 | 24.8 76.6 335 16 8 11.1 6.1 8250 23.3 73.9 320 12 6 8.9 4.9 | 25.7 78.3 335 15 8 13.1 7.2 8000 23.8 74.8 310 11 6 8.0 4.4 | 26.6 79.9 335 15 8 9.9 5.4 7750 24.4 75.9 300 9 5 11.1 6.1 | 27.4 81.3 335 15 8 15.3 8.4 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 07/12/2024 at 1500 MDT | 07/12/2024 at 1800 MDT | CAPE... +10.6 LI... 0.0 | CAPE... +24.7 LI... +0.2 CINH... -22.7 K Index... +12.4 | CINH... -26.0 K Index... +18.0 | 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 -60.9 -77.6 285 4 2 2.1 1.1 | -60.9 -77.6 305 11 5 0.9 0.5 45000 -56.7 -70.1 315 13 6 4.0 2.2 | -57.8 -72.0 315 18 9 3.9 2.1 40000 -50.7 -59.3 350 26 13 4.3 2.3 | -51.6 -60.9 340 18 9 5.4 3.0 38000 -48.1 -54.6 340 25 13 4.3 2.3 | -48.4 -55.1 330 20 10 5.4 3.0 36000 -45.2 -49.4 330 25 13 6.8 3.7 | -45.2 -49.4 320 22 11 6.0 3.3 34000 -40.5 -40.9 330 25 13 7.8 4.3 | -40.0 -40.0 320 22 11 7.9 4.3 32000 -35.9 -32.6 330 24 12 7.9 4.3 | -35.3 -31.5 325 22 11 8.0 4.4 30000 -31.2 -24.2 330 23 12 7.7 4.2 | -30.5 -22.9 325 21 11 8.0 4.4 29000 -28.9 -20.0 330 22 12 7.7 4.2 | -28.1 -18.6 330 20 10 8.0 4.4 28000 -26.6 -15.9 330 22 11 8.0 4.4 | -25.7 -14.3 330 20 10 7.6 4.2 27000 -24.2 -11.6 330 20 10 7.9 4.4 | -23.5 -10.3 330 19 10 7.6 4.2 26000 -21.8 -7.2 330 19 10 7.9 4.4 | -21.2 -6.2 330 18 9 7.6 4.2 25000 -19.4 -2.9 325 18 9 7.9 4.3 | -18.9 -2.0 330 18 9 7.5 4.1 24000 -17.1 1.2 330 18 9 7.8 4.3 | -16.7 1.9 330 18 9 7.5 4.1 23000 -14.8 5.4 330 18 9 7.8 4.3 | -14.5 5.9 330 18 9 7.6 4.2 22000 -12.4 9.7 330 19 10 7.8 4.3 | -12.3 9.9 330 17 9 8.1 4.5 21000 -9.6 14.7 325 20 11 7.9 4.3 | -9.3 15.3 335 17 9 8.4 4.6 20000 -7.3 18.9 325 22 11 7.9 4.4 | -6.9 19.6 345 17 9 8.4 4.6 19500 -6.1 21.0 325 22 11 8.7 4.7 | -5.6 21.9 345 17 9 8.9 4.9 19000 -4.8 23.4 325 22 11 8.8 4.8 | -4.3 24.3 350 17 9 9.0 4.9 18500 -3.5 25.7 325 22 12 8.9 4.9 | -3.0 26.6 350 17 9 9.0 5.0 18000 -2.2 28.0 330 22 11 9.4 5.2 | -1.6 29.1 355 17 9 9.3 5.1 17500 -0.8 30.6 330 22 11 9.4 5.1 | -0.2 31.6 355 16 8 9.2 5.1 17000 0.6 33.1 330 22 11 9.2 5.0 | 1.1 34.0 355 16 8 9.5 5.2 16500 1.9 35.4 335 22 11 9.1 5.0 | 2.6 36.7 355 16 8 9.5 5.2 16000 3.3 37.9 335 22 11 9.2 5.0 | 4.0 39.2 360 16 8 9.4 5.1 15500 4.7 40.5 335 21 11 9.3 5.1 | 5.3 41.5 360 15 8 9.1 5.0 15000 6.1 43.0 340 20 10 9.3 5.1 | 6.7 44.1 360 15 8 9.1 5.0 14500 7.4 45.3 340 19 10 9.5 5.2 | 8.1 46.6 360 15 8 9.4 5.2 14000 8.8 47.8 345 19 10 9.4 5.2 | 9.5 49.1 005 14 7 9.4 5.2 13500 10.2 50.4 345 18 9 9.6 5.3 | 10.9 51.6 005 14 7 9.2 5.1 13000 11.7 53.1 345 17 9 9.9 5.4 | 12.2 54.0 005 14 7 9.3 5.1 12500 13.2 55.8 350 17 9 10.5 5.7 | 13.7 56.7 005 14 7 10.0 5.5 12000 14.8 58.6 350 17 9 11.0 6.0 | 15.2 59.4 005 14 7 10.5 5.8 11750 15.6 60.1 350 17 9 9.5 5.2 | 15.9 60.6 005 14 7 9.3 5.1 11500 16.2 61.2 350 17 9 9.1 5.0 | 16.6 61.9 005 14 7 9.2 5.0 11250 17.0 62.6 350 17 9 10.5 5.7 | 17.4 63.3 005 14 7 10.5 5.7 11000 17.7 63.9 350 17 9 10.1 5.5 | 18.1 64.6 005 14 7 10.1 5.5 10750 18.5 65.3 350 17 9 10.7 5.9 | 18.9 66.0 005 14 7 10.6 5.8 10500 19.3 66.7 350 17 9 8.6 4.7 | 19.6 67.3 005 14 7 8.9 4.9 10250 19.8 67.6 350 17 9 8.4 4.6 | 20.2 68.4 005 14 7 8.7 4.7 10000 20.6 69.1 350 17 9 10.4 5.7 | 21.0 69.8 005 14 7 10.1 5.6 9750 21.3 70.3 350 17 9 9.9 5.5 | 21.7 71.1 360 14 7 10.0 5.5 9500 22.1 71.8 350 17 9 9.9 5.4 | 22.5 72.5 360 14 7 9.0 4.9 9250 22.8 73.0 350 16 8 10.2 5.6 | 23.1 73.6 360 14 7 9.3 5.1 9000 23.6 74.5 350 16 8 10.6 5.8 | 23.9 75.0 360 14 7 10.7 5.9 8750 24.4 75.9 350 16 8 10.5 5.8 | 24.6 76.3 360 14 7 10.4 5.7 8500 25.2 77.4 350 16 8 10.5 5.7 | 25.4 77.7 360 13 7 10.3 5.6 8250 26.0 78.8 350 16 8 12.0 6.6 | 26.2 79.2 360 13 7 10.8 5.9 8000 27.1 80.8 350 16 8 19.3 10.6 | 27.1 80.8 360 13 7 13.9 7.6 7750 28.8 83.8 350 14 7 27.5 15.1 | 28.2 82.8 360 12 6 17.5 9.6 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