Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
815 UXUS97 KPUB 241233 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0633 MDT Tuesday, September 24, 2024 This forecast is for the Air Force Academy for Tuesday, September 24, 2024: If the trigger temperature of 62.3 F/16.8 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 757 ft/min (3.8 m/s) Maximum height of thermals.................. 17243 ft MSL (9664 ft AGL) Forecast maximum temperature................... 73.0 F/23.2 C Time of trigger temperature.................... 1000 MDT Time of overdevelopment........................ None Middle/high clouds during soaring window....... Overcast thin high Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 15596 ft MSL (8017 ft AGL) Thermal soaring outlook for Wednesday 09/25.... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 06:49:37 / 18:52:29 MDT Total possible sunshine........... 12 hr 2 min 52 sec (722 min 52 sec) Altitude of sun at 12:51:03 MDT... 50.08 degrees Upper air data from numerical model forecast valid on 09/24/2024 at 0600 MDT Freezing level.................. 13627 ft MSL (6048 ft AGL) Convective condensation level... 19365 ft MSL (11786 ft AGL) Lifted condensation level....... 17967 ft MSL (10388 ft AGL) Lifted index.................... +2.6 K index......................... +11.4 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 -60.9 -77.6 010 43 22 1.2 0.6 M M M M M 45000 -59.1 -74.4 020 57 30 1.3 0.7 M M M M M 40000 -56.9 -70.4 025 77 40 6.8 3.7 M M M M M 38000 -52.4 -62.3 030 77 40 7.5 4.1 M M M M M 36000 -47.9 -54.2 035 77 40 7.5 4.1 M M M M M 34000 -42.4 -44.3 030 68 35 8.5 4.7 M M M M M 32000 -37.3 -35.1 020 57 30 8.5 4.7 M M M M M 30000 -32.2 -26.0 015 51 26 8.5 4.7 36.7 98.1 10.8 M M 29000 -29.7 -21.5 015 48 25 8.5 4.7 36.2 97.2 10.5 M M 28000 -27.2 -17.0 015 46 24 8.4 4.6 35.9 96.6 10.4 M M 27000 -24.9 -12.8 010 44 23 7.4 4.0 35.0 95.0 9.7 M M 26000 -22.7 -8.9 005 42 22 7.4 4.1 34.1 93.3 9.1 M M 25000 -20.6 -5.1 005 41 21 7.4 4.1 33.3 91.9 8.5 M M 24000 -18.4 -1.1 360 39 20 7.5 4.1 32.4 90.4 7.9 M M 23000 -16.1 3.0 360 37 19 7.5 4.1 31.6 88.9 7.2 M M 22000 -13.9 7.0 360 35 18 7.6 4.1 30.8 87.5 6.6 M M 21000 -12.0 10.4 355 32 17 6.0 3.3 29.7 85.5 5.7 M M 20000 -9.8 14.4 340 28 14 6.0 3.3 28.1 82.6 4.3 M M 19500 -8.9 16.0 335 27 14 6.2 3.4 27.5 81.5 3.8 M M 19000 -8.1 17.4 330 26 13 4.2 2.3 26.8 80.2 3.2 M M 18500 -7.5 18.5 325 26 13 4.1 2.2 25.8 78.4 2.3 M M 18000 -6.9 19.6 320 25 13 3.6 2.0 24.9 76.8 1.5 M M 17500 -6.5 20.3 320 24 12 2.3 1.2 23.7 74.6 0.4 M M 17000 -6.2 20.8 325 22 11 2.1 1.1 22.4 72.4 -0.7 841 4.3 16500 -5.7 21.7 325 20 10 4.8 2.6 21.4 70.5 -1.7 811 4.1 16000 -5.0 23.0 330 19 10 4.8 2.6 20.5 69.0 -2.5 776 3.9 15500 -4.3 24.3 335 19 10 6.3 3.4 19.8 67.6 -3.2 739 3.8 15000 -3.2 26.2 335 19 10 7.3 4.0 19.4 66.8 -3.6 692 3.5 14500 -2.1 28.2 340 20 10 7.6 4.2 19.0 66.2 -4.0 645 3.3 14000 -0.9 30.4 340 22 11 8.5 4.7 18.7 65.7 -4.3 593 3.0 13500 0.4 32.7 340 24 12 8.5 4.7 18.5 65.4 -4.5 541 2.7 13000 1.6 34.9 340 27 14 8.1 4.4 18.3 65.0 -4.8 490 2.5 12500 2.8 37.0 335 28 14 8.6 4.7 18.1 64.6 -5.0 438 2.2 12000 4.0 39.2 335 27 14 7.1 3.9 17.8 64.0 -5.4 389 2.0 11750 4.5 40.1 335 26 13 6.8 3.7 17.6 63.6 -5.6 366 1.9 11500 5.1 41.2 330 25 13 10.9 6.0 17.4 63.4 -5.7 341 1.7 11250 6.0 42.8 330 25 13 10.0 5.5 17.6 63.7 -5.6 307 1.6 11000 6.5 43.7 330 25 13 6.0 3.3 17.4 63.3 -5.9 285 1.4 10750 6.9 44.4 330 25 13 6.3 3.5 17.1 62.9 -6.1 263 1.3 10500 7.4 45.3 330 25 13 8.9 4.9 16.9 62.4 -6.4 240 1.2 10250 8.2 46.8 330 25 13 10.1 5.5 17.0 62.6 -6.3 210 1.1 10000 8.8 47.8 330 24 13 8.0 4.4 16.9 62.4 -6.5 184 0.9 9750 9.5 49.1 335 24 12 8.6 4.7 16.8 62.2 -6.6 158 0.8 9500 10.1 50.2 335 24 12 8.5 4.6 16.7 62.0 -6.7 132 0.7 9250 10.6 51.1 335 23 12 5.6 3.1 16.5 61.7 -6.9 108 0.5 9000 10.9 51.6 335 22 11 4.7 2.6 16.1 61.0 -7.3 91 0.5 8750 11.4 52.5 335 21 11 6.3 3.5 15.8 60.5 -7.7 71 0.4 8500 11.8 53.2 340 19 10 5.6 3.1 15.5 59.9 -8.0 50 0.3 8250 12.2 54.0 340 18 9 3.8 2.1 15.2 59.3 -8.4 32 0.2 8000 12.0 53.6 340 18 9 -10.1 -5.6 14.3 57.8 -9.2 28 0.1 7750 10.5 50.9 335 12 6 -29.8 -16.3 12.0 53.6 -11.6 69 0.3 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 * * * * * * 09/24/2024 at 0900 MDT | 09/24/2024 at 1200 MDT | CAPE... 0.0 LI... +4.4 | CAPE... 0.0 LI... +5.1 CINH... 0.0 K Index... +12.5 | CINH... 0.0 K Index... +11.6 | 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 -62.0 -79.6 010 46 24 1.2 0.7 | -62.7 -80.9 020 39 20 1.4 0.7 45000 -60.0 -76.0 015 62 32 1.8 1.0 | -60.0 -76.0 020 57 29 2.6 1.4 40000 -56.4 -69.5 025 73 37 8.1 4.4 | -55.5 -67.9 025 62 32 7.9 4.3 38000 -51.6 -60.9 030 68 35 8.0 4.4 | -50.9 -59.6 025 59 30 7.8 4.3 36000 -46.8 -52.2 030 63 32 8.0 4.4 | -46.2 -51.2 025 56 29 7.7 4.3 34000 -41.7 -43.1 020 57 29 8.5 4.7 | -41.3 -42.3 020 51 26 8.3 4.5 32000 -36.6 -33.9 010 53 27 8.4 4.6 | -35.8 -32.4 010 46 24 8.2 4.5 30000 -31.6 -24.9 005 51 26 8.3 4.6 | -30.8 -23.4 010 45 23 8.4 4.6 29000 -29.1 -20.4 005 50 26 8.3 4.6 | -28.3 -18.9 010 45 23 8.4 4.6 28000 -26.6 -15.9 360 50 26 8.2 4.5 | -25.8 -14.4 015 44 23 7.9 4.3 27000 -24.3 -11.7 005 47 24 7.6 4.2 | -23.6 -10.5 010 43 22 7.4 4.1 26000 -22.0 -7.6 005 45 23 7.6 4.2 | -21.4 -6.5 010 41 21 7.4 4.1 25000 -19.8 -3.6 005 43 22 7.7 4.2 | -19.2 -2.6 010 40 20 7.4 4.1 24000 -17.6 0.3 005 41 21 6.8 3.8 | -17.0 1.4 005 37 19 7.5 4.1 23000 -15.1 4.8 005 39 20 6.9 3.8 | -14.8 5.4 360 35 18 7.5 4.1 22000 -13.1 8.4 360 38 20 6.7 3.7 | -12.6 9.3 355 33 17 7.6 4.2 21000 -11.3 11.7 355 34 18 6.1 3.3 | -10.6 12.9 350 32 17 6.5 3.6 20000 -9.5 14.9 350 31 16 6.1 3.3 | -8.7 16.3 350 31 16 6.5 3.6 19500 -8.6 16.5 345 29 15 6.0 3.3 | -7.2 19.0 350 30 15 6.6 3.6 19000 -7.7 18.1 340 28 14 7.5 4.1 | -6.4 20.5 350 29 15 5.0 2.7 18500 -6.6 20.1 335 26 13 7.5 4.1 | -5.7 21.7 345 28 14 5.2 2.8 18000 -5.4 22.3 330 25 13 6.3 3.5 | -4.9 23.2 345 27 14 5.6 3.1 17500 -4.8 23.4 325 24 12 3.6 2.0 | -4.1 24.6 340 26 13 6.0 3.3 17000 -4.3 24.3 325 23 12 3.7 2.0 | -3.2 26.2 340 25 13 6.1 3.4 16500 -3.8 25.2 325 22 11 3.1 1.7 | -2.5 27.5 335 24 13 4.1 2.3 16000 -3.4 25.9 330 21 11 3.1 1.7 | -1.9 28.6 335 24 12 4.4 2.4 15500 -2.9 26.8 335 21 11 3.6 2.0 | -1.3 29.7 335 23 12 3.1 1.7 15000 -2.4 27.7 335 20 10 3.9 2.2 | -0.9 30.4 335 21 11 2.8 1.5 14500 -1.8 28.8 340 20 10 4.5 2.5 | -0.6 30.9 330 20 10 3.2 1.8 14000 -1.0 30.2 345 19 10 6.1 3.4 | 0.0 32.0 330 19 10 3.9 2.2 13500 -0.1 31.8 350 18 9 6.2 3.4 | 0.6 33.1 325 17 9 4.2 2.3 13000 1.0 33.8 355 18 9 7.8 4.3 | 1.3 34.3 330 16 8 5.7 3.1 12500 2.0 35.6 355 18 9 6.6 3.6 | 2.1 35.8 330 16 8 5.3 2.9 12000 3.2 37.8 355 17 9 9.2 5.1 | 3.2 37.8 330 15 8 9.1 5.0 11750 3.9 39.0 350 17 9 9.5 5.2 | 3.9 39.0 330 15 8 8.8 4.9 11500 4.6 40.3 350 17 9 7.4 4.1 | 4.5 40.1 330 15 8 7.0 3.8 11250 5.1 41.2 350 17 9 5.7 3.1 | 5.0 41.0 330 15 8 6.7 3.7 11000 5.5 41.9 350 17 9 6.6 3.6 | 5.6 42.1 330 14 7 8.2 4.5 10750 6.0 42.8 350 17 9 6.7 3.7 | 6.2 43.2 330 14 7 7.6 4.2 10500 6.5 43.7 350 17 9 5.5 3.0 | 6.7 44.1 330 14 7 8.5 4.7 10250 6.8 44.2 345 17 9 4.1 2.3 | 7.4 45.3 325 14 7 8.8 4.8 10000 7.1 44.8 350 17 9 4.3 2.3 | 8.0 46.4 330 13 6 8.2 4.5 9750 7.4 45.3 350 17 9 4.2 2.3 | 8.6 47.5 335 12 6 8.5 4.7 9500 7.8 46.0 350 18 9 4.2 2.3 | 9.2 48.6 340 11 5 7.7 4.2 9250 8.0 46.4 355 18 9 3.4 1.9 | 9.7 49.5 345 10 5 8.4 4.6 9000 8.3 46.9 355 18 9 3.4 1.9 | 10.5 50.9 345 10 5 10.8 6.0 8750 8.5 47.3 355 18 9 3.8 2.1 | 11.3 52.3 345 10 5 11.6 6.3 8500 8.8 47.8 355 17 9 4.1 2.3 | 12.1 53.8 345 10 5 10.7 5.9 8250 9.1 48.4 350 17 9 5.5 3.0 | 12.9 55.2 350 10 5 9.8 5.4 8000 9.7 49.5 345 16 8 10.8 5.9 | 13.8 56.8 350 9 5 16.8 9.2 7750 10.7 51.3 340 13 7 18.0 9.9 | 15.5 59.9 350 9 5 28.1 15.4 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 09/24/2024 at 1500 MDT | 09/24/2024 at 1800 MDT | CAPE... 0.0 LI... +4.9 | CAPE... 0.0 LI... +4.0 CINH... 0.0 K Index... +10.4 | CINH... 0.0 K Index... +10.1 | 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 -65.0 -85.0 015 34 17 1.9 1.0 | -65.0 -85.0 005 30 15 1.8 1.0 45000 -61.3 -78.3 020 49 25 3.5 1.9 | -61.2 -78.2 015 40 20 4.0 2.2 40000 -55.4 -67.7 020 54 28 7.7 4.2 | -54.7 -66.5 020 47 24 7.1 3.9 38000 -50.7 -59.3 015 51 26 7.8 4.3 | -50.4 -58.7 015 44 22 7.2 3.9 36000 -46.1 -51.0 015 49 25 7.8 4.3 | -46.1 -51.0 015 41 21 7.0 3.9 34000 -41.0 -41.8 015 44 23 8.5 4.7 | -40.5 -40.9 015 38 20 8.6 4.7 32000 -35.3 -31.5 015 39 20 8.5 4.6 | -35.3 -31.5 015 37 19 8.8 4.8 30000 -30.2 -22.4 015 37 19 8.5 4.7 | -30.0 -22.0 015 37 19 8.9 4.9 29000 -27.7 -17.9 015 36 19 8.5 4.7 | -27.3 -17.1 015 37 19 9.0 4.9 28000 -25.1 -13.2 015 36 18 8.0 4.4 | -24.7 -12.5 015 36 19 7.9 4.3 27000 -22.8 -9.0 015 35 18 7.7 4.2 | -22.4 -8.3 020 33 17 7.7 4.2 26000 -20.5 -4.9 020 35 18 7.8 4.3 | -20.1 -4.2 020 30 15 7.7 4.2 25000 -18.2 -0.8 025 35 18 7.8 4.3 | -17.8 -0.0 025 26 13 7.7 4.2 24000 -16.1 3.0 020 32 17 7.0 3.8 | -15.3 4.5 025 25 13 8.4 4.6 23000 -14.0 6.8 020 29 15 7.0 3.9 | -12.8 9.0 030 24 13 8.5 4.6 22000 -11.9 10.6 015 27 14 7.0 3.9 | -10.3 13.5 030 24 12 8.2 4.5 21000 -9.9 14.2 010 26 13 6.8 3.7 | -8.5 16.7 025 23 12 5.9 3.2 20000 -7.4 18.7 360 26 13 6.8 3.7 | -6.3 20.7 015 22 11 5.9 3.2 19500 -6.4 20.5 360 26 13 6.7 3.7 | -5.4 22.3 010 22 11 5.8 3.2 19000 -5.5 22.1 355 26 13 6.1 3.4 | -4.6 23.7 010 23 12 5.2 2.9 18500 -4.6 23.7 355 26 13 6.2 3.4 | -3.9 25.0 005 23 12 5.3 2.9 18000 -3.7 25.3 355 25 13 5.2 2.8 | -3.1 26.4 005 24 12 4.9 2.7 17500 -3.1 26.4 350 25 13 4.6 2.5 | -2.4 27.7 360 25 13 4.8 2.6 17000 -2.4 27.7 350 25 13 4.6 2.5 | -1.7 28.9 360 25 13 4.5 2.5 16500 -1.9 28.6 345 26 13 3.7 2.0 | -1.3 29.7 355 26 13 2.0 1.1 16000 -1.4 29.5 340 26 13 3.8 2.1 | -1.1 30.0 355 26 14 2.0 1.1 15500 -0.8 30.6 340 26 13 4.2 2.3 | -0.7 30.7 350 26 14 5.2 2.8 15000 -0.2 31.6 335 25 13 4.3 2.4 | 0.1 32.2 345 26 13 5.6 3.1 14500 0.4 32.7 335 25 13 5.2 2.9 | 0.8 33.4 340 25 13 7.8 4.3 14000 1.3 34.3 330 24 12 6.0 3.3 | 2.2 36.0 330 23 12 9.3 5.1 13500 2.1 35.8 325 23 12 6.3 3.5 | 3.6 38.5 320 21 11 9.2 5.0 13000 3.2 37.8 320 22 11 7.2 3.9 | 4.9 40.8 310 20 10 8.6 4.7 12500 4.2 39.6 315 20 10 6.6 3.6 | 6.0 42.8 310 19 10 6.7 3.7 12000 5.1 41.2 315 17 9 6.4 3.5 | 6.8 44.2 310 16 8 4.6 2.5 11750 5.6 42.1 320 16 8 6.4 3.5 | 7.2 45.0 310 15 8 4.8 2.6 11500 6.0 42.8 320 15 8 6.0 3.3 | 7.5 45.5 310 13 7 4.4 2.4 11250 6.5 43.7 325 14 7 8.2 4.5 | 7.8 46.0 310 12 6 4.3 2.3 11000 7.2 45.0 330 13 7 9.9 5.4 | 8.2 46.8 320 11 6 4.3 2.4 10750 8.0 46.4 335 12 6 9.9 5.4 | 8.5 47.3 330 10 5 4.6 2.5 10500 8.7 47.7 345 11 6 8.2 4.5 | 8.8 47.8 340 10 5 3.2 1.8 10250 9.2 48.6 350 11 6 8.4 4.6 | 9.1 48.4 355 9 5 6.5 3.6 10000 10.0 50.0 350 11 6 10.3 5.7 | 9.8 49.6 360 9 5 10.2 5.6 9750 10.7 51.3 350 11 6 10.1 5.5 | 10.5 50.9 005 9 5 9.5 5.2 9500 11.5 52.7 350 11 6 9.3 5.1 | 11.2 52.2 010 9 5 8.8 4.8 9250 12.1 53.8 350 11 5 9.2 5.0 | 11.8 53.2 010 9 5 8.7 4.8 9000 12.9 55.2 355 11 5 10.8 5.9 | 12.5 54.5 010 9 5 10.4 5.7 8750 13.7 56.7 355 11 5 11.3 6.2 | 13.3 55.9 010 9 5 10.9 6.0 8500 14.5 58.1 355 11 5 10.8 5.9 | 14.1 57.4 015 9 5 10.3 5.7 8250 15.3 59.5 355 11 5 10.5 5.8 | 14.8 58.6 015 9 5 9.5 5.2 8000 16.2 61.2 355 10 5 16.5 9.1 | 15.6 60.1 015 9 5 10.3 5.7 7750 17.8 64.0 360 10 5 25.5 14.0 | 16.4 61.5 015 8 4 12.0 6.6 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