Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
980 UXUS97 KPUB 231201 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0601 MDT Sunday, June 23, 2024 This forecast is for the Air Force Academy for Sunday, June 23, 2024: If the trigger temperature of 73.5 F/23.1 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1241 ft/min (6.3 m/s) Maximum height of thermals.................. 21325 ft MSL (13720 ft AGL) Forecast maximum temperature................... 91.0 F/33.2 C Time of trigger temperature.................... 0900 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................. 18637 ft MSL (11032 ft AGL) Thermal soaring outlook for Monday 06/24....... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:34:40 / 20:28:44 MDT Total possible sunshine........... 14 hr 54 min 4 sec (894 min 4 sec) Altitude of sun at 13:01:42 MDT... 74.42 degrees Upper air data from numerical model forecast valid on 06/23/2024 at 0600 MDT Freezing level.................. 16404 ft MSL (8799 ft AGL) Convective condensation level... 19305 ft MSL (11700 ft AGL) Lifted condensation level....... 20514 ft MSL (12909 ft AGL) Lifted index.................... -3.2 K index......................... +1.5 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 -62.7 -80.9 275 45 23 2.7 1.5 M M M M M 45000 -57.6 -71.7 265 60 31 4.7 2.6 M M M M M 40000 -49.6 -57.3 265 69 36 7.0 3.8 M M M M M 38000 -45.4 -49.7 265 67 34 7.0 3.8 M M M M M 36000 -41.2 -42.2 265 64 33 6.8 3.7 M M M M M 34000 -37.2 -35.0 270 51 26 6.7 3.7 M M M M M 32000 -33.2 -27.8 270 37 19 6.8 3.7 M M M M M 30000 -29.0 -20.2 275 23 12 7.0 3.8 39.7 103.5 5.4 M M 29000 -26.9 -16.4 275 16 8 7.0 3.8 38.7 101.7 4.7 M M 28000 -24.8 -12.6 280 10 5 7.8 4.3 37.8 100.1 4.0 M M 27000 -22.4 -8.3 290 8 4 7.9 4.3 37.0 98.6 3.4 M M 26000 -20.0 -4.0 305 6 3 7.9 4.3 36.3 97.4 2.9 M M 25000 -17.7 0.1 330 5 2 7.9 4.3 35.8 96.4 2.5 M M 24000 -15.3 4.5 335 6 3 7.9 4.4 35.0 95.0 1.9 M M 23000 -12.3 9.9 330 9 5 7.9 4.4 34.2 93.6 1.2 M M 22000 -10.0 14.0 330 11 6 6.3 3.5 33.5 92.4 0.7 M M 21000 -8.1 17.4 325 11 6 6.3 3.4 32.2 90.0 -0.5 1206 6.1 20000 -6.3 20.7 320 12 6 6.3 3.5 31.1 88.0 -1.5 1120 5.7 19500 -5.3 22.5 320 12 6 6.2 3.4 30.6 87.0 -2.0 1078 5.5 19000 -4.5 23.9 320 13 7 6.0 3.3 29.9 85.8 -2.6 1037 5.3 18500 -3.6 25.5 320 14 7 6.1 3.3 29.3 84.7 -3.2 996 5.1 18000 -2.8 27.0 325 14 7 5.7 3.1 28.6 83.5 -3.9 955 4.9 17500 -1.9 28.6 325 15 8 5.7 3.1 27.9 82.3 -4.5 916 4.7 17000 -1.1 30.0 330 16 8 6.1 3.3 27.3 81.1 -5.2 877 4.5 16500 -0.1 31.8 330 16 8 6.8 3.7 26.7 80.1 -5.7 833 4.2 16000 0.8 33.4 330 16 8 6.7 3.7 26.3 79.3 -6.2 788 4.0 15500 1.9 35.4 330 16 8 7.7 4.2 25.9 78.5 -6.7 742 3.8 15000 3.0 37.4 330 15 8 7.6 4.2 25.5 77.9 -7.1 693 3.5 14500 4.2 39.6 330 14 7 8.0 4.4 25.2 77.4 -7.4 644 3.3 14000 5.3 41.5 335 14 7 8.1 4.5 24.9 76.9 -7.8 594 3.0 13500 6.5 43.7 335 13 7 7.9 4.3 24.7 76.4 -8.1 544 2.8 13000 7.6 45.7 335 14 7 7.8 4.3 24.3 75.8 -8.5 496 2.5 12500 8.9 48.0 335 14 7 8.9 4.9 24.1 75.5 -8.7 444 2.3 12000 10.1 50.2 335 15 8 8.5 4.7 23.9 75.1 -9.0 393 2.0 11750 10.7 51.3 335 16 8 8.3 4.5 23.8 74.9 -9.2 367 1.9 11500 11.3 52.3 335 16 8 8.0 4.4 23.7 74.7 -9.4 342 1.7 11250 11.9 53.4 335 17 9 8.8 4.8 23.6 74.5 -9.5 317 1.6 11000 12.5 54.5 335 17 9 9.3 5.1 23.6 74.4 -9.6 290 1.5 10750 13.2 55.8 335 17 9 9.3 5.1 23.5 74.3 -9.7 263 1.3 10500 13.8 56.8 335 17 9 8.9 4.9 23.5 74.3 -9.8 236 1.2 10250 14.4 57.9 330 17 9 8.4 4.6 23.4 74.1 -10.0 211 1.1 10000 15.0 59.0 330 17 9 8.3 4.6 23.3 73.9 -10.2 186 0.9 9750 15.6 60.1 325 16 8 8.6 4.7 23.2 73.7 -10.3 161 0.8 9500 16.2 61.2 325 16 8 7.7 4.2 23.1 73.5 -10.5 136 0.7 9250 16.6 61.9 320 16 8 4.8 2.6 22.8 73.1 -10.8 116 0.6 9000 16.8 62.2 315 16 8 3.3 1.8 22.3 72.2 -11.4 102 0.5 8750 17.0 62.6 305 15 8 3.9 2.1 21.9 71.4 -11.9 88 0.4 8500 17.2 63.0 300 15 8 2.8 1.5 21.4 70.5 -12.5 75 0.4 8250 17.3 63.1 295 15 8 0.3 0.1 20.8 69.4 -13.2 65 0.3 8000 16.8 62.2 290 13 7 -18.3 -10.1 19.6 67.2 -14.4 72 0.4 7750 14.3 57.7 285 11 5 -46.2 -25.4 16.3 61.4 -17.7 141 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 * * * * * * 06/23/2024 at 0900 MDT | 06/23/2024 at 1200 MDT | CAPE... +259.0 LI... +0.1 | CAPE... +0.9 LI... +1.7 CINH... -23.0 K Index... +3.7 | CINH... -0.4 K Index... +9.7 | 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 -62.5 -80.5 275 39 20 3.1 1.7 | -63.2 -81.8 275 38 20 3.6 2.0 45000 -56.8 -70.2 270 55 29 4.6 2.5 | -56.6 -69.9 270 52 27 5.1 2.8 40000 -49.3 -56.7 265 64 33 6.7 3.7 | -48.8 -55.8 265 59 31 6.2 3.4 38000 -45.3 -49.5 265 60 31 6.7 3.7 | -45.0 -49.0 265 57 29 6.2 3.4 36000 -41.3 -42.3 265 57 29 6.6 3.6 | -41.3 -42.3 265 55 28 6.3 3.5 34000 -37.4 -35.3 265 45 23 6.5 3.6 | -36.9 -34.4 265 42 22 6.5 3.6 32000 -33.0 -27.4 275 32 17 6.7 3.7 | -33.0 -27.4 260 30 15 7.1 3.9 30000 -28.9 -20.0 265 21 11 6.9 3.8 | -28.7 -19.7 255 25 13 7.3 4.0 29000 -26.8 -16.2 260 16 8 6.9 3.8 | -26.5 -15.7 255 23 12 7.3 4.0 28000 -24.7 -12.5 250 12 6 7.6 4.2 | -24.3 -11.7 250 20 11 6.8 3.7 27000 -22.5 -8.5 250 10 5 7.5 4.1 | -22.3 -8.1 245 17 9 6.9 3.8 26000 -20.2 -4.4 250 7 4 7.5 4.1 | -20.2 -4.4 240 14 7 6.9 3.8 25000 -18.0 -0.4 245 5 3 7.8 4.3 | -18.2 -0.8 230 11 6 7.6 4.1 24000 -15.5 4.1 265 5 2 8.1 4.4 | -15.7 3.7 230 11 6 8.3 4.6 23000 -13.1 8.4 285 5 2 8.1 4.4 | -13.2 8.2 235 11 5 8.3 4.6 22000 -10.7 12.7 300 5 3 7.0 3.9 | -10.7 12.7 235 10 5 7.0 3.9 21000 -8.9 16.0 295 7 3 6.1 3.3 | -8.9 16.0 245 10 5 5.8 3.2 20000 -6.7 19.9 285 8 4 6.1 3.4 | -6.8 19.8 255 9 5 5.9 3.2 19500 -5.8 21.6 285 9 5 6.2 3.4 | -5.9 21.4 260 9 5 5.7 3.1 19000 -4.8 23.4 290 9 5 6.3 3.4 | -5.1 22.8 265 8 4 5.6 3.1 18500 -3.9 25.0 295 9 5 6.5 3.6 | -4.3 24.3 270 8 4 5.6 3.1 18000 -3.1 26.4 305 9 5 5.0 2.7 | -3.5 25.7 280 7 4 6.5 3.6 17500 -2.4 27.7 315 10 5 5.3 2.9 | -2.6 27.3 290 7 4 6.5 3.6 17000 -1.7 28.9 325 10 5 6.0 3.3 | -1.6 29.1 300 7 4 6.7 3.7 16500 -0.7 30.7 335 10 5 6.6 3.6 | -0.7 30.7 315 7 4 6.9 3.8 16000 0.2 32.4 345 11 6 6.8 3.7 | 0.3 32.5 325 8 4 7.1 3.9 15500 1.3 34.3 350 12 6 8.5 4.6 | 1.4 34.5 335 8 4 8.5 4.7 15000 2.6 36.7 355 12 6 8.3 4.6 | 2.6 36.7 345 8 4 8.5 4.7 14500 3.8 38.8 360 12 6 9.0 5.0 | 3.8 38.8 350 8 4 9.6 5.2 14000 5.2 41.4 360 13 7 9.1 5.0 | 5.2 41.4 355 8 4 9.6 5.3 13500 6.5 43.7 360 13 7 8.1 4.4 | 6.6 43.9 355 9 4 9.6 5.3 13000 7.6 45.7 355 13 7 8.1 4.5 | 8.0 46.4 355 9 4 9.9 5.4 12500 8.9 48.0 350 13 7 9.3 5.1 | 9.6 49.3 355 9 4 10.4 5.7 12000 10.2 50.4 345 14 7 8.7 4.8 | 11.1 52.0 355 9 4 10.5 5.8 11750 10.8 51.4 345 14 7 8.0 4.4 | 11.8 53.2 355 9 4 9.3 5.1 11500 11.3 52.3 345 14 7 8.0 4.4 | 12.5 54.5 355 9 4 8.8 4.8 11250 12.0 53.6 340 15 8 9.0 5.0 | 13.2 55.8 355 9 4 10.1 5.6 11000 12.6 54.7 340 15 8 9.2 5.1 | 14.0 57.2 355 9 5 10.2 5.6 10750 13.3 55.9 340 16 8 9.0 5.0 | 14.7 58.5 355 9 5 10.4 5.7 10500 13.9 57.0 335 16 8 9.7 5.3 | 15.5 59.9 355 9 5 9.5 5.2 10250 14.6 58.3 335 16 8 9.7 5.3 | 16.2 61.2 355 9 5 9.3 5.1 10000 15.2 59.4 335 17 9 8.9 4.9 | 16.9 62.4 355 9 5 10.0 5.5 9750 15.9 60.6 335 17 9 9.4 5.2 | 17.6 63.7 355 9 5 10.1 5.6 9500 16.5 61.7 335 17 9 8.4 4.6 | 18.4 65.1 355 9 5 8.8 4.8 9250 17.1 62.8 330 17 9 7.8 4.3 | 19.0 66.2 355 9 5 9.2 5.0 9000 17.7 63.9 330 17 9 8.6 4.7 | 19.8 67.6 355 9 5 11.1 6.1 8750 18.3 64.9 330 16 8 8.5 4.6 | 20.6 69.1 355 9 5 10.7 5.9 8500 18.8 65.8 325 16 8 8.8 4.8 | 21.4 70.5 360 9 5 11.0 6.0 8250 19.5 67.1 320 14 7 9.5 5.2 | 22.2 72.0 360 9 5 12.4 6.8 8000 20.1 68.2 320 13 7 9.4 5.2 | 23.3 73.9 360 9 4 18.7 10.3 7750 20.8 69.4 315 11 6 13.4 7.3 | 25.0 77.0 360 8 4 26.4 14.5 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 06/23/2024 at 1500 MDT | 06/23/2024 at 1800 MDT | CAPE... +5.9 LI... +0.3 | CAPE... +10.8 LI... -0.5 CINH... -0.0 K Index... +21.4 | CINH... -5.8 K Index... +26.3 | 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 -63.7 -82.7 275 39 20 3.4 1.9 | -63.7 -82.7 270 40 20 3.4 1.9 45000 -57.0 -70.6 270 52 27 5.6 3.1 | -56.9 -70.4 270 52 27 5.7 3.1 40000 -48.4 -55.1 265 60 31 6.3 3.4 | -48.2 -54.8 270 60 31 6.3 3.5 38000 -44.6 -48.3 265 58 30 6.3 3.4 | -44.5 -48.1 270 58 30 6.3 3.5 36000 -40.9 -41.6 265 57 29 6.3 3.5 | -40.7 -41.3 270 56 29 6.4 3.5 34000 -36.5 -33.7 265 47 24 6.5 3.6 | -36.2 -33.2 265 47 24 6.6 3.6 32000 -32.6 -26.7 260 38 19 6.8 3.7 | -32.2 -26.0 265 38 20 6.9 3.8 30000 -28.3 -18.9 265 33 17 7.2 3.9 | -28.1 -18.6 265 34 17 7.0 3.8 29000 -26.2 -15.2 265 31 16 7.2 3.9 | -26.0 -14.8 265 32 16 7.0 3.9 28000 -24.0 -11.2 265 29 15 7.6 4.2 | -23.9 -11.0 265 30 15 7.7 4.2 27000 -21.7 -7.1 265 26 14 7.6 4.2 | -21.6 -6.9 265 27 14 7.7 4.2 26000 -19.5 -3.1 265 24 12 7.6 4.2 | -19.4 -2.9 270 24 13 7.7 4.2 25000 -17.2 1.0 260 21 11 7.2 3.9 | -17.1 1.2 270 22 11 7.1 3.9 24000 -15.2 4.6 260 19 10 6.7 3.7 | -15.3 4.5 270 20 10 6.2 3.4 23000 -13.2 8.2 255 16 8 6.7 3.7 | -13.5 7.7 275 18 9 6.3 3.4 22000 -11.2 11.8 250 14 7 6.3 3.5 | -11.7 10.9 275 16 8 6.2 3.4 21000 -9.5 14.9 260 15 8 6.0 3.3 | -10.0 14.0 285 12 6 6.0 3.3 20000 -7.4 18.7 270 16 8 6.1 3.4 | -7.8 18.0 305 7 3 6.1 3.3 19500 -6.5 20.3 275 16 8 5.9 3.2 | -6.9 19.6 325 5 3 6.3 3.4 19000 -5.7 21.7 280 14 7 5.7 3.1 | -6.0 21.2 010 4 2 6.4 3.5 18500 -4.9 23.2 290 13 6 5.5 3.0 | -5.1 22.8 050 5 3 6.3 3.4 18000 -3.9 25.0 300 10 5 8.1 4.5 | -4.0 24.8 060 6 3 8.2 4.5 17500 -2.8 27.0 315 7 4 7.9 4.3 | -2.8 27.0 060 6 3 8.1 4.4 17000 -1.7 28.9 345 6 3 8.5 4.7 | -1.6 29.1 065 5 3 8.8 4.8 16500 -0.4 31.3 005 5 2 9.0 5.0 | -0.2 31.6 065 5 3 9.5 5.2 16000 0.9 33.6 030 4 2 9.1 5.0 | 1.2 34.2 070 5 3 9.6 5.2 15500 2.3 36.1 035 4 2 9.6 5.3 | 2.6 36.7 075 5 3 9.6 5.3 15000 3.7 38.7 040 4 2 9.5 5.2 | 4.0 39.2 075 5 2 9.6 5.3 14500 5.2 41.4 040 4 2 10.2 5.6 | 5.5 41.9 080 4 2 9.6 5.3 14000 6.7 44.1 040 4 2 10.2 5.6 | 6.9 44.4 090 4 2 9.6 5.3 13500 8.2 46.8 045 4 2 9.7 5.3 | 8.3 46.9 095 4 2 9.7 5.3 13000 9.6 49.3 045 4 2 9.8 5.4 | 9.8 49.6 110 4 2 9.6 5.3 12500 11.1 52.0 045 4 2 10.3 5.6 | 11.2 52.2 115 4 2 9.9 5.4 12000 12.6 54.7 050 4 2 10.4 5.7 | 12.7 54.9 130 4 2 11.0 6.0 11750 13.4 56.1 050 4 2 9.7 5.3 | 13.5 56.3 135 4 2 9.4 5.2 11500 14.1 57.4 050 4 2 9.3 5.1 | 14.1 57.4 135 4 2 8.1 4.5 11250 14.8 58.6 050 4 2 9.9 5.4 | 14.8 58.6 140 4 2 9.5 5.2 11000 15.6 60.1 050 4 2 9.9 5.4 | 15.5 59.9 140 4 2 9.8 5.4 10750 16.3 61.3 055 4 2 10.1 5.5 | 16.3 61.3 145 4 2 10.0 5.5 10500 17.0 62.6 055 4 2 9.3 5.1 | 17.0 62.6 150 4 2 8.9 4.9 10250 17.7 63.9 055 4 2 9.3 5.1 | 17.6 63.7 150 5 2 8.9 4.9 10000 18.4 65.1 055 4 2 9.9 5.4 | 18.3 64.9 150 5 2 9.9 5.4 9750 19.2 66.6 055 4 2 10.2 5.6 | 19.1 66.4 150 5 2 9.9 5.4 9500 19.9 67.8 055 4 2 8.4 4.6 | 19.8 67.6 155 5 3 9.0 4.9 9250 20.5 68.9 055 4 2 9.3 5.1 | 20.5 68.9 155 5 3 9.1 5.0 9000 21.3 70.3 060 4 2 11.8 6.5 | 21.2 70.2 155 5 3 10.3 5.6 8750 22.2 72.0 060 4 2 11.5 6.3 | 22.0 71.6 155 5 3 10.0 5.5 8500 23.0 73.4 060 4 2 10.5 5.8 | 22.7 72.9 160 5 3 10.2 5.6 8250 23.8 74.8 060 4 2 10.3 5.6 | 23.5 74.3 160 6 3 11.2 6.2 8000 24.7 76.5 060 4 2 17.8 9.7 | 24.4 75.9 160 5 3 13.7 7.5 7750 26.4 79.5 060 4 2 26.9 14.8 | 25.5 77.9 160 5 3 16.1 8.9 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