Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
081 UXUS97 KPUB 201252 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0652 MDT Saturday, July 20, 2024 This forecast is for the Air Force Academy for Saturday, July 20, 2024: If the trigger temperature of 71.2 F/21.8 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 616 ft/min (3.1 m/s) Maximum height of thermals.................. 18104 ft MSL (10495 ft AGL) Forecast maximum temperature................... 78.0 F/26.0 C Time of trigger temperature.................... 0900 MDT Time of overdevelopment........................ 1300 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................. 12512 ft MSL (4903 ft AGL) Thermal soaring outlook for Sunday 07/21....... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:50:39 / 20:20:48 MDT Total possible sunshine........... 14 hr 30 min 9 sec (870 min 9 sec) Altitude of sun at 13:05:43 MDT... 71.43 degrees Upper air data from numerical model forecast valid on 07/20/2024 at 0600 MDT Freezing level.................. 15576 ft MSL (7967 ft AGL) Convective condensation level... 15923 ft MSL (8314 ft AGL) Lifted condensation level....... 16600 ft MSL (8991 ft AGL) Lifted index.................... -1.6 K index......................... +23.1 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 -63.4 -82.1 335 34 17 1.9 1.0 M M M M M 45000 -57.2 -71.0 325 44 22 7.3 4.0 M M M M M 40000 -46.4 -51.5 320 49 25 6.7 3.7 M M M M M 38000 -42.4 -44.3 320 50 26 6.7 3.7 M M M M M 36000 -38.4 -37.1 320 51 26 6.4 3.5 M M M M M 34000 -35.6 -32.1 320 46 24 3.8 2.1 M M M M M 32000 -33.4 -28.1 320 41 21 4.7 2.6 M M M M M 30000 -29.1 -20.4 320 37 19 7.3 4.0 39.7 103.5 11.1 M M 29000 -26.9 -16.4 320 36 18 7.3 4.0 38.9 102.0 10.5 M M 28000 -24.8 -12.6 325 34 17 6.7 3.7 38.0 100.4 9.9 M M 27000 -22.8 -9.0 325 32 17 6.7 3.7 36.8 98.2 9.0 M M 26000 -20.8 -5.4 325 31 16 6.7 3.7 35.7 96.2 8.2 M M 25000 -18.8 -1.8 325 29 15 6.4 3.5 34.7 94.4 7.4 M M 24000 -17.1 1.2 325 28 14 5.8 3.2 33.2 91.7 6.2 M M 23000 -15.4 4.3 330 26 14 5.8 3.2 31.8 89.2 5.1 M M 22000 -13.7 7.3 335 25 13 6.0 3.3 30.5 86.8 4.0 M M 21000 -11.9 10.6 340 22 11 6.2 3.4 29.1 84.4 2.8 M M 20000 -9.7 14.5 345 18 9 6.4 3.5 27.7 81.8 1.4 M M 19500 -8.8 16.2 345 17 9 7.0 3.8 27.1 80.9 0.9 M M 19000 -7.7 18.1 345 16 8 7.6 4.1 26.8 80.2 0.6 M M 18500 -6.6 20.1 340 14 7 7.6 4.2 26.4 79.5 0.2 M M 18000 -5.5 22.1 340 13 7 7.2 4.0 26.0 78.8 -0.1 999 5.1 17500 -4.4 24.1 345 12 6 7.3 4.0 25.6 78.1 -0.6 953 4.8 17000 -3.4 25.9 345 11 6 7.8 4.3 25.2 77.4 -0.9 906 4.6 16500 -2.2 28.0 350 11 5 8.1 4.5 24.9 76.9 -1.2 855 4.3 16000 -0.9 30.4 350 10 5 8.2 4.5 24.7 76.4 -1.4 804 4.1 15500 0.3 32.5 355 9 5 8.1 4.4 24.4 76.0 -1.7 753 3.8 15000 1.4 34.5 360 9 5 8.0 4.4 24.2 75.5 -2.0 703 3.6 14500 2.7 36.9 005 9 4 8.9 4.9 23.9 75.1 -2.2 651 3.3 14000 4.0 39.2 005 9 4 9.0 4.9 23.8 74.9 -2.4 597 3.0 13500 5.3 41.5 010 9 5 8.2 4.5 23.7 74.6 -2.6 544 2.8 13000 6.4 43.5 010 9 5 8.1 4.5 23.4 74.1 -2.9 495 2.5 12500 7.8 46.0 010 10 5 9.1 5.0 23.3 74.0 -3.0 439 2.2 12000 8.9 48.0 005 10 5 7.9 4.3 23.0 73.4 -3.3 390 2.0 11750 9.5 49.1 005 10 5 7.9 4.3 22.9 73.2 -3.5 366 1.9 11500 10.1 50.2 005 10 5 8.0 4.4 22.7 72.9 -3.7 341 1.7 11250 10.6 51.1 005 10 5 7.7 4.2 22.6 72.6 -3.8 317 1.6 11000 11.2 52.2 360 10 5 7.9 4.3 22.4 72.4 -4.0 293 1.5 10750 11.7 53.1 360 10 5 7.2 4.0 22.3 72.1 -4.2 268 1.4 10500 12.3 54.1 355 10 5 9.7 5.3 22.1 71.8 -4.4 244 1.2 10250 13.1 55.6 355 10 5 9.4 5.1 22.2 71.9 -4.3 214 1.1 10000 13.6 56.5 350 10 5 6.9 3.8 22.0 71.6 -4.6 191 1.0 9750 14.1 57.4 345 10 5 7.0 3.8 21.8 71.3 -4.8 168 0.9 9500 14.6 58.3 340 9 5 9.1 5.0 21.6 70.9 -5.0 145 0.7 9250 15.3 59.5 340 10 5 8.1 4.4 21.6 70.9 -5.1 117 0.6 9000 15.7 60.3 335 10 5 3.8 2.1 21.3 70.3 -5.5 100 0.5 8750 15.9 60.6 330 10 5 3.9 2.2 20.8 69.5 -6.0 85 0.4 8500 16.1 61.0 330 10 5 3.6 2.0 20.4 68.7 -6.4 70 0.4 8250 16.3 61.3 325 10 5 2.1 1.1 19.9 67.8 -7.0 57 0.3 8000 16.4 61.5 320 10 5 1.2 0.6 19.3 66.7 -7.7 48 0.2 7750 16.0 60.8 310 10 5 -15.2 -8.3 18.2 64.8 -8.8 51 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 * * * * * * 07/20/2024 at 0900 MDT | 07/20/2024 at 1200 MDT | CAPE... +442.9 LI... -2.9 | CAPE... +920.8 LI... -4.7 CINH... -29.5 K Index... +21.7 | CINH... 0.0 K Index... +27.4 | 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 -63.1 -81.6 335 32 17 1.9 1.0 | -62.2 -80.0 330 28 14 1.9 1.0 45000 -57.1 -70.8 320 44 23 7.0 3.9 | -56.8 -70.2 315 44 22 6.3 3.4 40000 -46.7 -52.1 315 50 26 6.3 3.4 | -47.4 -53.3 305 55 28 6.3 3.5 38000 -43.0 -45.4 315 50 26 6.3 3.5 | -43.6 -46.5 310 52 27 6.3 3.5 36000 -39.2 -38.6 315 50 26 6.0 3.3 | -39.8 -39.6 310 50 26 6.3 3.5 34000 -36.6 -33.9 315 45 23 3.7 2.0 | -36.6 -33.9 315 44 23 4.5 2.5 32000 -34.4 -29.9 315 40 21 4.9 2.7 | -33.9 -29.0 315 38 20 4.8 2.6 30000 -29.7 -21.5 320 36 18 8.1 4.4 | -30.0 -22.0 315 34 17 6.8 3.7 29000 -27.3 -17.1 325 33 17 8.1 4.4 | -28.0 -18.4 315 32 16 6.8 3.7 28000 -25.0 -13.0 325 31 16 6.9 3.8 | -25.9 -14.6 315 30 15 7.4 4.1 27000 -22.9 -9.2 325 29 15 7.0 3.8 | -23.7 -10.7 315 29 15 7.4 4.1 26000 -20.8 -5.4 330 26 13 7.0 3.8 | -21.5 -6.7 315 27 14 7.4 4.1 25000 -18.7 -1.7 330 24 12 6.5 3.6 | -19.2 -2.6 310 26 14 6.8 3.7 24000 -17.0 1.4 330 22 12 5.7 3.1 | -17.6 0.3 315 24 12 5.4 3.0 23000 -15.3 4.5 330 21 11 5.8 3.2 | -16.0 3.2 315 21 11 5.5 3.0 22000 -13.7 7.3 335 20 10 6.2 3.4 | -14.5 5.9 315 19 10 6.2 3.4 21000 -11.8 10.8 335 19 10 6.5 3.6 | -12.4 9.7 315 18 9 7.1 3.9 20000 -9.4 15.1 335 17 9 6.5 3.6 | -9.9 14.2 320 16 8 7.2 3.9 19500 -8.5 16.7 335 17 9 7.1 3.9 | -8.9 16.0 325 16 8 7.2 4.0 19000 -7.4 18.7 330 16 8 7.5 4.1 | -7.9 17.8 325 16 8 7.2 3.9 18500 -6.3 20.7 330 16 8 7.5 4.1 | -6.8 19.8 325 16 8 7.1 3.9 18000 -5.2 22.6 330 15 8 7.8 4.3 | -5.7 21.7 320 15 8 8.1 4.4 17500 -4.0 24.8 325 15 8 7.8 4.3 | -4.6 23.7 320 15 8 8.0 4.4 17000 -2.9 26.8 325 14 7 7.5 4.1 | -3.4 25.9 315 14 7 7.9 4.3 16500 -1.9 28.6 320 13 7 7.4 4.0 | -2.3 27.9 310 14 7 7.9 4.3 16000 -0.8 30.6 315 12 6 7.5 4.1 | -1.2 29.8 310 13 7 7.8 4.3 15500 0.3 32.5 320 11 5 8.0 4.4 | -0.1 31.8 310 13 7 6.9 3.8 15000 1.5 34.7 320 10 5 8.0 4.4 | 0.9 33.6 310 12 6 6.9 3.8 14500 2.7 36.9 325 9 5 7.7 4.2 | 2.0 35.6 315 12 6 7.7 4.2 14000 3.8 38.8 330 9 5 7.7 4.2 | 3.1 37.6 325 12 6 7.7 4.2 13500 4.9 40.8 335 9 4 7.2 4.0 | 4.2 39.6 330 12 6 7.1 3.9 13000 5.9 42.6 345 9 5 7.3 4.0 | 5.2 41.4 340 12 6 7.1 3.9 12500 7.1 44.8 345 9 5 8.6 4.7 | 6.3 43.3 350 13 7 7.8 4.3 12000 8.2 46.8 350 10 5 7.5 4.1 | 7.3 45.1 355 14 7 7.5 4.1 11750 8.8 47.8 355 10 5 8.5 4.6 | 7.7 45.9 360 15 8 5.7 3.1 11500 9.4 48.9 355 10 5 8.0 4.4 | 8.1 46.6 005 16 8 7.2 4.0 11250 9.9 49.8 355 11 5 6.4 3.5 | 8.7 47.7 005 16 8 10.0 5.5 11000 10.4 50.7 355 11 6 7.0 3.9 | 9.4 48.9 005 17 9 9.4 5.2 10750 10.9 51.6 350 11 6 6.2 3.4 | 10.0 50.0 005 17 9 9.4 5.1 10500 11.4 52.5 350 12 6 9.1 5.0 | 10.7 51.3 005 17 9 10.5 5.7 10250 12.1 53.8 350 12 6 8.5 4.7 | 11.5 52.7 005 17 9 10.3 5.6 10000 12.5 54.5 350 13 6 5.2 2.9 | 12.2 54.0 005 17 9 9.1 5.0 9750 12.9 55.2 350 13 7 6.0 3.3 | 12.9 55.2 005 17 9 9.0 4.9 9500 13.3 55.9 345 13 7 6.2 3.4 | 13.6 56.5 005 17 9 11.2 6.1 9250 13.7 56.7 345 14 7 7.6 4.2 | 14.5 58.1 005 17 9 11.8 6.5 9000 14.2 57.6 345 14 7 8.4 4.6 | 15.2 59.4 005 17 9 9.6 5.3 8750 14.8 58.6 345 13 7 8.5 4.7 | 15.9 60.6 005 17 9 9.8 5.4 8500 15.5 59.9 345 13 7 10.2 5.6 | 16.7 62.1 005 16 8 10.9 6.0 8250 16.3 61.3 350 13 7 11.9 6.5 | 17.6 63.7 005 16 8 12.4 6.8 8000 17.1 62.8 350 13 7 8.9 4.9 | 18.4 65.1 005 16 8 9.2 5.1 7750 17.7 63.9 350 12 6 12.0 6.6 | 19.2 66.6 005 16 8 16.2 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 07/20/2024 at 1500 MDT | 07/20/2024 at 1800 MDT | CAPE... +854.1 LI... -3.3 | CAPE... +623.0 LI... -2.4 CINH... 0.0 K Index... +29.1 | CINH... -0.6 K Index... +28.8 | 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 -62.1 -79.8 325 30 16 2.2 1.2 | -61.7 -79.1 315 36 19 2.1 1.2 45000 -56.6 -69.9 310 47 24 5.9 3.3 | -56.4 -69.5 310 54 28 5.7 3.1 40000 -47.6 -53.7 305 59 30 6.5 3.6 | -47.8 -54.0 305 62 32 5.7 3.1 38000 -43.7 -46.7 305 56 29 6.5 3.6 | -44.4 -47.9 305 58 30 5.7 3.1 36000 -39.4 -38.9 305 54 28 5.3 2.9 | -40.6 -41.1 305 54 28 5.5 3.0 34000 -36.6 -33.9 305 46 24 4.6 2.5 | -37.4 -35.3 305 48 25 5.3 2.9 32000 -33.8 -28.8 305 38 20 4.9 2.7 | -34.2 -29.6 300 42 21 5.6 3.1 30000 -30.2 -22.4 305 32 16 6.2 3.4 | -30.3 -22.5 300 35 18 6.6 3.6 29000 -28.3 -18.9 305 29 15 6.2 3.4 | -28.3 -18.9 300 32 17 6.6 3.6 28000 -26.4 -15.5 305 26 14 7.7 4.2 | -26.3 -15.3 300 29 15 7.9 4.3 27000 -24.1 -11.4 305 27 14 7.8 4.3 | -23.9 -11.0 305 26 13 7.9 4.4 26000 -21.7 -7.1 305 27 14 7.8 4.3 | -21.5 -6.7 315 23 12 7.9 4.4 25000 -19.4 -2.9 305 28 14 7.4 4.0 | -19.1 -2.4 325 21 11 7.5 4.1 24000 -17.5 0.5 310 27 14 6.2 3.4 | -17.2 1.0 325 22 11 6.4 3.5 23000 -15.7 3.7 315 26 13 6.3 3.4 | -15.3 4.5 330 23 12 6.4 3.5 22000 -13.3 8.1 325 25 13 7.9 4.3 | -12.9 8.8 330 24 13 7.7 4.2 21000 -11.0 12.2 330 25 13 7.9 4.3 | -10.7 12.7 335 25 13 7.8 4.3 20000 -8.8 16.2 335 24 13 7.9 4.3 | -8.5 16.7 335 26 13 7.9 4.3 19500 -7.6 18.3 335 24 13 7.4 4.1 | -7.3 18.9 335 26 14 7.6 4.2 19000 -6.6 20.1 335 24 12 7.0 3.8 | -6.3 20.7 335 26 13 7.2 4.0 18500 -5.7 21.7 335 23 12 7.0 3.8 | -5.3 22.5 340 25 13 7.4 4.1 18000 -4.7 23.5 335 22 11 7.0 3.9 | -4.4 24.1 340 24 13 6.0 3.3 17500 -3.7 25.3 330 20 10 7.1 3.9 | -3.5 25.7 340 24 12 6.1 3.4 17000 -2.7 27.1 330 19 10 6.9 3.8 | -2.7 27.1 345 23 12 6.0 3.3 16500 -1.7 28.9 325 18 9 6.8 3.7 | -1.8 28.8 345 22 11 5.8 3.2 16000 -0.7 30.7 325 17 9 6.7 3.7 | -1.0 30.2 345 20 10 5.8 3.2 15500 0.2 32.4 325 17 9 6.2 3.4 | -0.2 31.6 345 19 10 5.9 3.2 15000 1.1 34.0 325 16 8 6.3 3.4 | 0.6 33.1 345 17 9 5.9 3.2 14500 1.9 35.4 325 15 8 5.9 3.3 | 1.4 34.5 345 14 7 5.4 3.0 14000 2.7 36.9 335 14 7 6.0 3.3 | 2.2 36.0 355 10 5 5.4 3.0 13500 3.5 38.3 340 13 7 6.2 3.4 | 2.9 37.2 020 7 3 7.0 3.8 13000 4.3 39.7 005 12 6 6.6 3.6 | 4.0 39.2 040 7 4 7.8 4.3 12500 5.5 41.9 020 12 6 10.0 5.5 | 5.3 41.5 050 8 4 10.8 5.9 12000 6.9 44.4 025 13 7 9.9 5.4 | 6.8 44.2 055 8 4 10.8 5.9 11750 7.7 45.9 025 13 7 10.4 5.7 | 7.6 45.7 055 8 4 8.9 4.9 11500 8.4 47.1 025 13 7 10.2 5.6 | 8.2 46.8 055 8 4 8.1 4.4 11250 9.1 48.4 030 13 7 9.3 5.1 | 8.9 48.0 055 8 4 9.8 5.4 11000 9.8 49.6 030 13 7 9.7 5.3 | 9.6 49.3 055 8 4 10.1 5.6 10750 10.5 50.9 030 13 7 8.7 4.8 | 10.3 50.5 055 8 4 9.0 5.0 10500 11.2 52.2 030 13 7 12.3 6.7 | 11.1 52.0 055 8 4 13.1 7.2 10250 12.3 54.1 030 13 7 12.2 6.7 | 12.2 54.0 055 8 4 12.4 6.8 10000 13.0 55.4 030 13 7 8.7 4.8 | 12.8 55.0 055 8 4 8.1 4.4 9750 13.7 56.7 030 13 7 9.2 5.0 | 13.5 56.3 055 8 4 8.8 4.8 9500 14.3 57.7 030 13 7 10.6 5.8 | 14.1 57.4 055 8 4 10.3 5.7 9250 15.2 59.4 030 13 7 11.0 6.0 | 15.0 59.0 055 8 4 10.8 6.0 9000 15.9 60.6 030 13 7 9.2 5.0 | 15.7 60.3 060 8 4 9.0 4.9 8750 16.6 61.9 030 13 7 9.1 5.0 | 16.4 61.5 060 8 4 8.9 4.9 8500 17.3 63.1 030 13 7 10.7 5.9 | 17.0 62.6 060 8 4 10.1 5.5 8250 18.2 64.8 030 13 7 12.5 6.8 | 18.6 65.5 060 8 4 8.7 4.7 8000 19.0 66.2 030 13 7 9.3 5.1 | 19.2 66.6 060 8 4 9.5 5.2 7750 19.7 67.5 030 12 6 13.5 7.4 | 20.6 69.1 060 7 4 37.7 20.7 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