880 UXUS97 KPUB 251207 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0507 MST Saturday, January 25, 2020 This forecast is for Saturday, January 25, 2020: If the trigger temperature of 39.6 F/4.2 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 552 ft/min (2.8 m/s) Maximum height of thermals.................. 18158 ft MSL (10532 ft AGL) Forecast maximum temperature................... 51.0 F/11.0 C Time of trigger temperature.................... 0930 MST Time of overdevelopment........................ None 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................. 15060 ft MSL (7434 ft AGL) Thermal soaring outlook for Sunday 01/26....... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 07:11:23 / 17:11:44 MST Total possible sunshine........... 10 hr 0 min 21 sec (600 min 21 sec) Altitude of sun at 12:11:33 MST... 32.01 degrees Upper air data from numerical model forecast valid on 01/25/2020 at 0500 MST Freezing level.................. 8013 ft MSL (387 ft AGL) Additional freezing level....... 8681 ft MSL (1055 ft AGL) Convective condensation level... 13909 ft MSL (6283 ft AGL) Lifted condensation level....... 15664 ft MSL (8038 ft AGL) Lifted index.................... -0.7 K index......................... +16.6 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 -55.3 -67.5 295 11 6 3.0 1.7 M M M M M 45000 -50.7 -59.3 295 14 7 2.5 1.4 M M M M M 40000 -49.4 -56.9 295 18 9 0.8 0.5 M M M M M 38000 -48.9 -56.0 295 19 10 0.6 0.3 M M M M M 36000 -48.6 -55.5 305 18 9 0.6 0.3 M M M M M 34000 -48.2 -54.8 315 18 9 1.1 0.6 M M M M M 32000 -47.3 -53.1 310 16 8 1.6 0.9 M M M M M 30000 -46.3 -51.3 310 15 7 3.0 1.7 M M M M M 29000 -44.9 -48.8 305 13 7 4.6 2.5 21.1 69.9 8.2 M M 28000 -43.5 -46.3 300 12 6 4.6 2.5 19.1 66.3 6.7 M M 27000 -42.1 -43.8 295 10 5 4.7 2.6 17.2 63.0 5.3 M M 26000 -40.2 -40.4 290 9 5 7.8 4.3 16.0 60.8 4.4 M M 25000 -37.8 -36.0 295 8 4 7.9 4.3 15.2 59.4 3.8 M M 24000 -34.9 -30.8 300 6 3 8.0 4.4 14.5 58.1 3.2 M M 23000 -32.5 -26.5 300 7 3 8.1 4.4 13.8 56.9 2.7 M M 22000 -30.1 -22.2 305 7 4 8.1 4.4 13.2 55.8 2.2 M M 21000 -27.7 -17.9 305 7 4 8.0 4.4 12.7 54.9 1.8 M M 20000 -25.4 -13.7 310 8 4 7.8 4.3 12.0 53.5 1.1 M M 19500 -24.2 -11.6 315 8 4 7.8 4.3 11.6 52.9 0.8 M M 19000 -23.0 -9.4 320 8 4 7.8 4.3 11.3 52.4 0.5 M M 18500 -21.9 -7.4 320 8 4 7.5 4.1 11.0 51.9 0.3 M M 18000 -20.9 -5.6 325 8 4 6.4 3.5 10.5 50.9 -0.2 936 4.8 17500 -19.9 -3.8 325 8 4 6.4 3.5 10.0 50.0 -0.7 892 4.5 17000 -18.9 -2.0 330 8 4 7.1 3.9 9.5 49.1 -1.2 847 4.3 16500 -17.9 -0.2 330 9 4 7.1 3.9 9.0 48.3 -1.6 801 4.1 16000 -16.8 1.8 335 9 5 6.7 3.7 8.6 47.5 -2.0 755 3.8 15500 -15.9 3.4 335 9 5 6.5 3.6 8.1 46.5 -2.5 711 3.6 15000 -14.9 5.2 340 9 5 6.7 3.7 7.5 45.6 -3.0 668 3.4 14500 -13.9 7.0 340 9 5 7.3 4.0 7.1 44.8 -3.5 621 3.2 14000 -12.8 9.0 345 9 5 7.2 4.0 6.7 44.1 -3.9 575 2.9 13500 -11.8 10.8 345 9 5 6.7 3.7 6.2 43.2 -4.4 530 2.7 13000 -10.8 12.6 345 9 5 6.9 3.8 5.8 42.4 -4.9 485 2.5 12500 -9.6 14.7 345 9 5 7.9 4.3 5.6 42.0 -5.1 433 2.2 12000 -8.6 16.5 345 9 5 6.3 3.5 5.0 41.0 -5.7 391 2.0 11750 -8.1 17.4 340 9 5 7.7 4.2 4.8 40.6 -6.0 369 1.9 11500 -7.5 18.5 340 10 5 9.0 5.0 4.7 40.4 -6.1 342 1.7 11250 -6.8 19.8 340 11 5 9.0 4.9 4.6 40.3 -6.2 315 1.6 11000 -6.2 20.8 340 11 6 9.1 5.0 4.6 40.2 -6.2 287 1.5 10750 -5.5 22.1 340 12 6 8.8 4.8 4.5 40.1 -6.3 260 1.3 10500 -4.8 23.4 340 12 6 8.4 4.6 4.4 39.9 -6.4 233 1.2 10250 -4.2 24.4 340 13 7 9.4 5.2 4.3 39.8 -6.5 206 1.0 10000 -3.4 25.9 340 13 7 10.2 5.6 4.3 39.8 -6.5 175 0.9 9750 -2.7 27.1 340 13 7 9.3 5.1 4.3 39.8 -6.5 146 0.7 9500 -2.0 28.4 340 13 7 9.1 5.0 4.3 39.7 -6.6 118 0.6 9250 -1.3 29.7 340 13 6 8.8 4.8 4.2 39.6 -6.6 91 0.5 9000 -0.7 30.7 335 12 6 6.8 3.7 4.1 39.4 -6.8 65 0.3 8750 -0.3 31.5 335 12 6 5.4 3.0 3.8 38.8 -7.1 45 0.2 8500 0.1 32.2 335 11 5 6.2 3.4 3.5 38.3 -7.4 25 0.1 8250 0.5 32.9 330 9 5 3.7 2.0 3.2 37.7 -7.8 5 0.0 8000 0.4 32.7 325 9 4 -7.6 -4.2 2.4 36.2 -8.6 0 0.0 7750 -0.6 30.9 315 6 3 -18.5 -10.2 0.6 33.0 -10.4 24 0.1 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 * * * * * * 01/25/2020 at 0800 MST | 01/25/2020 at 1100 MST | CAPE... 0.0 LI... +1.7 | CAPE... 0.0 LI... +2.3 CINH... 0.0 K Index... +11.8 | CINH... 0.0 K Index... +3.1 | 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 -55.0 -67.0 300 9 5 2.8 1.5 | -55.5 -67.9 290 8 4 2.3 1.2 45000 -50.9 -59.6 300 11 5 2.4 1.3 | -52.1 -61.8 285 10 5 1.9 1.1 40000 -49.3 -56.7 305 18 9 0.9 0.5 | -50.3 -58.5 305 18 9 1.1 0.6 38000 -48.9 -56.0 310 20 10 0.4 0.2 | -49.8 -57.6 310 21 11 0.7 0.4 36000 -48.7 -55.7 315 21 11 0.4 0.2 | -49.4 -56.9 320 24 13 0.7 0.4 34000 -48.4 -55.1 325 22 11 1.2 0.7 | -48.9 -56.0 330 28 14 2.8 1.6 32000 -47.2 -53.0 320 22 11 2.1 1.1 | -46.6 -51.9 330 27 14 3.7 2.0 30000 -45.9 -50.6 320 22 11 3.8 2.1 | -44.4 -47.9 330 26 13 4.1 2.2 29000 -44.3 -47.7 320 21 11 5.5 3.0 | -43.1 -45.6 330 24 12 4.3 2.3 28000 -42.6 -44.7 320 20 10 5.5 3.0 | -41.8 -43.2 325 22 11 4.3 2.3 27000 -41.0 -41.8 315 19 10 5.5 3.0 | -40.5 -40.9 325 20 11 4.2 2.3 26000 -39.2 -38.6 315 17 9 6.2 3.4 | -38.7 -37.7 325 19 10 7.3 4.0 25000 -36.9 -34.4 310 13 7 6.2 3.4 | -35.9 -32.6 330 18 9 7.4 4.0 24000 -35.0 -31.0 300 10 5 6.0 3.3 | -33.7 -28.7 330 18 9 7.4 4.1 23000 -32.8 -27.0 300 9 5 7.9 4.4 | -31.8 -25.2 325 15 8 6.3 3.4 22000 -30.4 -22.7 300 8 4 8.0 4.4 | -29.9 -21.8 315 12 6 6.3 3.5 21000 -28.0 -18.4 300 7 4 7.9 4.3 | -28.0 -18.4 305 10 5 6.9 3.8 20000 -25.7 -14.3 305 8 4 7.7 4.2 | -25.7 -14.3 300 9 5 7.6 4.2 19500 -24.6 -12.3 310 8 4 7.7 4.2 | -24.6 -12.3 300 9 5 7.6 4.2 19000 -23.4 -10.1 315 9 5 7.7 4.2 | -23.4 -10.1 300 9 5 7.6 4.2 18500 -22.3 -8.1 320 9 5 7.5 4.1 | -22.3 -8.1 300 9 4 7.3 4.0 18000 -21.2 -6.2 320 9 5 7.1 3.9 | -21.3 -6.3 305 8 4 6.8 3.8 17500 -20.1 -4.2 325 9 5 7.1 3.9 | -20.2 -4.4 310 8 4 6.9 3.8 17000 -19.1 -2.4 325 9 5 7.1 3.9 | -19.2 -2.6 315 8 4 6.8 3.7 16500 -18.0 -0.4 325 9 5 7.1 3.9 | -18.2 -0.8 320 8 4 6.8 3.7 16000 -17.0 1.4 330 9 5 7.0 3.8 | -17.2 1.0 325 8 4 6.9 3.8 15500 -16.0 3.2 330 9 4 6.9 3.8 | -16.2 2.8 325 9 4 7.0 3.8 15000 -15.0 5.0 330 8 4 6.9 3.8 | -15.2 4.6 330 9 5 7.3 4.0 14500 -13.9 7.0 330 9 4 6.9 3.8 | -14.1 6.6 330 9 5 7.5 4.1 14000 -12.9 8.8 330 9 4 6.8 3.7 | -13.0 8.6 330 10 5 7.6 4.2 13500 -12.0 10.4 330 9 4 6.2 3.4 | -11.8 10.8 330 10 5 7.6 4.2 13000 -11.1 12.0 335 9 4 6.5 3.5 | -10.7 12.7 330 10 5 7.8 4.3 12500 -10.0 14.0 335 9 5 6.9 3.8 | -9.5 14.9 330 10 5 6.8 3.8 12000 -9.1 15.6 340 9 5 5.8 3.2 | -8.7 16.3 330 10 5 6.1 3.3 11750 -8.7 16.3 340 9 5 6.6 3.6 | -8.2 17.2 330 10 5 6.0 3.3 11500 -8.2 17.2 345 10 5 7.6 4.2 | -7.8 18.0 330 11 5 5.9 3.3 11250 -7.6 18.3 350 10 5 8.6 4.7 | -7.4 18.7 330 11 6 5.6 3.1 11000 -6.9 19.6 350 10 5 8.8 4.8 | -7.0 19.4 330 11 6 5.5 3.0 10750 -6.3 20.7 350 11 6 7.8 4.3 | -6.6 20.1 330 11 6 5.8 3.2 10500 -5.7 21.7 355 11 6 6.9 3.8 | -6.2 20.8 335 11 6 5.3 2.9 10250 -5.2 22.6 355 12 6 8.6 4.7 | -5.8 21.6 340 11 6 7.1 3.9 10000 -4.4 24.1 350 12 6 9.8 5.4 | -5.1 22.8 340 11 6 9.2 5.1 9750 -3.8 25.2 350 13 7 8.8 4.8 | -4.4 24.1 340 10 5 9.0 4.9 9500 -3.1 26.4 350 13 7 8.4 4.6 | -3.8 25.2 340 10 5 8.7 4.8 9250 -2.5 27.5 345 14 7 9.2 5.0 | -3.1 26.4 340 9 5 9.9 5.4 9000 -1.8 28.8 345 14 7 7.3 4.0 | -2.3 27.9 340 9 5 10.5 5.7 8750 -1.4 29.5 345 13 7 4.7 2.6 | -1.5 29.3 340 9 5 9.7 5.3 8500 -1.0 30.2 340 12 6 5.2 2.8 | -0.8 30.6 340 9 5 9.6 5.3 8250 -0.7 30.7 340 11 6 4.3 2.4 | -0.1 31.8 340 9 4 10.9 6.0 8000 -0.6 30.9 335 10 5 -5.1 -2.8 | 0.9 33.6 340 8 4 15.8 8.7 7750 -1.5 29.3 325 6 3 -18.0 -9.9 | 2.3 36.1 340 7 4 19.8 10.9 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 01/25/2020 at 1400 MST | 01/25/2020 at 1700 MST | CAPE... 0.0 LI... +4.1 | CAPE... 0.0 LI... +3.6 CINH... 0.0 K Index... -7.2 | CINH... 0.0 K Index... +1.9 | 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 -55.5 -67.9 290 9 5 2.0 1.1 | -55.7 -68.3 305 13 7 2.2 1.2 45000 -52.5 -62.5 295 13 7 1.6 0.9 | -52.4 -62.3 305 18 9 1.8 1.0 40000 -51.4 -60.5 300 22 12 0.7 0.4 | -51.5 -60.7 305 21 11 0.5 0.3 38000 -51.0 -59.8 305 24 12 0.7 0.4 | -51.0 -59.8 305 22 12 1.1 0.6 36000 -50.5 -58.9 315 24 12 0.7 0.4 | -50.4 -58.7 310 24 12 1.1 0.6 34000 -49.9 -57.8 320 24 13 4.0 2.2 | -49.6 -57.3 310 25 13 3.0 1.7 32000 -47.1 -52.8 320 25 13 4.7 2.6 | -47.5 -53.5 305 23 12 3.5 1.9 30000 -44.3 -47.7 320 25 13 4.7 2.6 | -45.4 -49.7 305 21 11 4.3 2.4 29000 -42.9 -45.2 325 25 13 4.6 2.5 | -44.0 -47.2 305 22 11 4.5 2.5 28000 -41.5 -42.7 325 26 13 4.6 2.5 | -42.7 -44.9 305 22 11 4.5 2.5 27000 -40.1 -40.2 325 26 13 4.5 2.5 | -41.4 -42.5 310 23 12 4.2 2.3 26000 -38.3 -36.9 330 25 13 6.9 3.8 | -39.2 -38.6 310 22 11 8.6 4.7 25000 -36.2 -33.2 330 24 12 6.9 3.8 | -36.6 -33.9 310 21 11 8.6 4.7 24000 -33.6 -28.5 330 22 11 7.1 3.9 | -33.4 -28.1 315 19 10 8.7 4.7 23000 -31.1 -24.0 335 21 11 8.4 4.6 | -30.7 -23.3 315 19 10 8.9 4.9 22000 -28.6 -19.5 335 21 11 8.4 4.6 | -28.0 -18.4 320 19 10 8.9 4.9 21000 -26.1 -15.0 335 20 10 7.9 4.3 | -25.4 -13.7 325 19 10 7.6 4.2 20000 -23.9 -11.0 335 19 10 7.5 4.1 | -23.3 -9.9 325 18 9 7.0 3.9 19500 -22.7 -8.9 330 18 9 7.5 4.1 | -22.2 -8.0 325 17 9 7.0 3.9 19000 -21.6 -6.9 330 17 9 7.5 4.1 | -21.2 -6.2 325 16 8 7.0 3.9 18500 -20.5 -4.9 330 17 9 7.0 3.8 | -20.1 -4.2 325 16 8 7.1 3.9 18000 -19.5 -3.1 330 15 8 6.3 3.5 | -19.0 -2.2 325 15 8 7.2 3.9 17500 -18.6 -1.5 330 14 7 6.3 3.4 | -18.0 -0.4 325 14 7 7.2 3.9 17000 -17.7 0.1 325 13 6 5.9 3.3 | -16.8 1.8 320 13 7 8.1 4.4 16500 -16.8 1.8 325 12 6 6.0 3.3 | -15.6 3.9 320 12 6 8.2 4.5 16000 -15.9 3.4 325 11 6 5.8 3.2 | -14.5 5.9 320 11 6 5.8 3.2 15500 -15.0 5.0 325 11 6 5.8 3.2 | -13.7 7.3 315 10 5 5.4 2.9 15000 -14.2 6.4 320 10 5 5.8 3.2 | -12.9 8.8 315 9 5 4.3 2.3 14500 -13.3 8.1 320 10 5 5.8 3.2 | -12.4 9.7 310 9 4 3.4 1.8 14000 -12.5 9.5 320 10 5 5.9 3.3 | -12.0 10.4 305 8 4 3.9 2.1 13500 -11.6 11.1 320 10 5 6.2 3.4 | -11.3 11.7 300 8 4 5.4 3.0 13000 -10.7 12.7 320 10 5 6.4 3.5 | -10.5 13.1 295 8 4 6.5 3.6 12500 -9.7 14.5 315 10 5 6.5 3.5 | -9.3 15.3 295 8 4 8.0 4.4 12000 -8.8 16.2 315 10 5 6.5 3.6 | -8.3 17.1 290 8 4 7.3 4.0 11750 -8.3 17.1 315 10 5 7.0 3.9 | -7.8 18.0 290 7 4 7.5 4.1 11500 -7.8 18.0 315 9 5 7.9 4.3 | -7.2 19.0 285 7 4 8.3 4.5 11250 -7.2 19.0 315 9 4 9.4 5.2 | -6.5 20.3 285 7 3 9.9 5.4 11000 -6.5 20.3 320 8 4 9.5 5.2 | -5.8 21.6 280 6 3 9.6 5.3 10750 -5.8 21.6 320 7 4 9.0 5.0 | -5.1 22.8 280 6 3 8.3 4.6 10500 -5.1 22.8 320 7 3 8.3 4.6 | -4.5 23.9 285 6 3 7.4 4.1 10250 -4.5 23.9 325 6 3 10.7 5.8 | -3.9 25.0 285 5 3 9.7 5.3 10000 -3.6 25.5 325 6 3 11.4 6.2 | -3.1 26.4 285 5 3 10.4 5.7 9750 -2.8 27.0 325 6 3 9.3 5.1 | -2.4 27.7 290 5 2 8.4 4.6 9500 -2.1 28.2 325 6 3 9.0 5.0 | -1.8 28.8 295 4 2 8.5 4.6 9250 -1.4 29.5 325 6 3 10.5 5.8 | -1.2 29.8 300 4 2 8.3 4.6 9000 -0.6 30.9 330 6 3 10.8 5.9 | -0.5 31.1 305 4 2 8.6 4.7 8750 0.1 32.2 330 6 3 9.5 5.2 | 0.1 32.2 315 3 2 8.8 4.8 8500 0.9 33.6 330 6 3 9.9 5.4 | 0.8 33.4 325 3 2 9.0 4.9 8250 1.6 34.9 330 6 3 9.6 5.3 | 1.4 34.5 335 3 2 7.9 4.4 8000 2.4 36.3 330 6 3 13.6 7.5 | 1.8 35.2 340 3 2 1.0 0.6 7750 3.7 38.7 335 5 3 20.5 11.2 | 1.5 34.7 345 3 1 -7.1 -3.9 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