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Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
087 UXUS97 KPUB 071208 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0608 MDT Sunday, July 7, 2024 This forecast is for the Air Force Academy for Sunday, July 7, 2024: If the trigger temperature of 70.4 F/21.3 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1243 ft/min (6.3 m/s) Maximum height of thermals.................. 19723 ft MSL (12118 ft AGL) Forecast maximum temperature................... 75.0 F/24.3 C Time of trigger temperature.................... 1045 MDT Time of overdevelopment........................ 1400 MDT Middle/high clouds during soaring window....... None Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 10962 ft MSL (3357 ft AGL) Thermal soaring outlook for Monday 07/08....... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:41:14 / 20:27:29 MDT Total possible sunshine........... 14 hr 46 min 15 sec (886 min 15 sec) Altitude of sun at 13:04:22 MDT... 73.46 degrees Upper air data from numerical model forecast valid on 07/07/2024 at 0600 MDT Freezing level.................. 15016 ft MSL (7411 ft AGL) Convective condensation level... 16361 ft MSL (8756 ft AGL) Lifted condensation level....... 17032 ft MSL (9427 ft AGL) Lifted index.................... -3.3 K index......................... +18.0 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 -57.5 -71.5 285 33 17 1.9 1.1 M M M M M 45000 -54.7 -66.5 285 46 24 1.7 0.9 M M M M M 40000 -52.1 -61.8 285 54 28 3.7 2.0 M M M M M 38000 -48.8 -55.8 285 52 27 4.9 2.7 M M M M M 36000 -45.8 -50.4 285 49 25 4.9 2.7 M M M M M 34000 -42.8 -45.0 285 45 23 5.0 2.7 M M M M M 32000 -39.8 -39.6 285 41 21 5.0 2.8 M M M M M 30000 -35.4 -31.7 290 38 19 8.5 4.7 32.9 91.2 7.0 M M 29000 -32.9 -27.2 290 36 19 8.5 4.7 32.4 90.4 6.7 M M 28000 -30.3 -22.5 295 35 18 8.7 4.7 32.1 89.7 6.5 M M 27000 -28.1 -18.6 295 35 18 7.1 3.9 31.2 88.1 5.9 M M 26000 -25.9 -14.6 295 35 18 7.1 3.9 30.2 86.3 5.1 M M 25000 -23.8 -10.8 295 36 18 7.1 3.9 29.3 84.7 4.4 M M 24000 -21.7 -7.1 300 36 18 7.0 3.8 28.3 82.9 3.7 M M 23000 -19.1 -2.4 300 36 19 7.0 3.8 27.0 80.6 2.6 M M 22000 -17.0 1.4 300 36 19 7.0 3.9 26.1 79.0 1.9 M M 21000 -14.9 5.2 295 34 17 7.1 3.9 25.1 77.3 1.0 M M 20000 -12.8 9.0 295 31 16 7.2 3.9 24.2 75.6 0.2 M M 19500 -11.8 10.8 290 30 15 7.1 3.9 23.9 74.9 -0.2 1216 6.2 19000 -10.6 12.9 290 28 14 8.5 4.7 23.5 74.4 -0.6 1167 5.9 18500 -9.4 15.1 285 26 13 8.5 4.7 23.3 74.0 -0.8 1116 5.7 18000 -8.2 17.2 285 23 12 8.8 4.8 23.1 73.6 -1.0 1064 5.4 17500 -6.9 19.6 285 22 11 9.2 5.0 23.0 73.4 -1.2 1009 5.1 17000 -5.5 22.1 280 20 10 9.1 5.0 22.9 73.2 -1.3 954 4.8 16500 -4.1 24.6 285 19 10 9.5 5.2 22.8 73.1 -1.4 898 4.6 16000 -2.7 27.1 285 18 9 9.5 5.2 22.8 73.0 -1.5 841 4.3 15500 -1.3 29.7 290 18 9 9.4 5.1 22.7 72.9 -1.5 784 4.0 15000 0.1 32.2 295 17 9 9.4 5.1 22.7 72.8 -1.6 728 3.7 14500 1.5 34.7 295 17 9 9.5 5.2 22.6 72.7 -1.7 671 3.4 14000 2.9 37.2 300 17 9 9.8 5.4 22.6 72.7 -1.7 613 3.1 13500 4.4 39.9 300 16 8 9.8 5.4 22.6 72.7 -1.7 554 2.8 13000 5.8 42.4 305 16 8 9.2 5.1 22.6 72.6 -1.8 497 2.5 12500 7.1 44.8 310 16 8 9.1 5.0 22.5 72.4 -1.9 442 2.2 12000 8.3 46.9 310 15 8 7.4 4.1 22.2 72.0 -2.2 391 2.0 11750 8.9 48.0 310 15 8 7.6 4.2 22.0 71.7 -2.3 367 1.9 11500 9.5 49.1 315 14 7 8.2 4.5 21.9 71.4 -2.5 342 1.7 11250 10.0 50.0 315 14 7 7.6 4.2 21.8 71.2 -2.6 317 1.6 11000 10.5 50.9 315 14 7 6.7 3.7 21.6 70.8 -2.9 295 1.5 10750 11.0 51.8 315 13 7 6.6 3.6 21.3 70.4 -3.2 273 1.4 10500 11.5 52.7 320 13 7 7.7 4.2 21.1 70.0 -3.4 252 1.3 10250 12.0 53.6 320 12 6 6.8 3.8 21.0 69.7 -3.6 228 1.2 10000 12.4 54.3 325 12 6 4.5 2.5 20.6 69.1 -4.0 211 1.1 9750 12.6 54.7 325 12 6 4.1 2.3 20.2 68.3 -4.5 195 1.0 9500 12.9 55.2 330 12 6 6.0 3.3 19.8 67.6 -5.0 180 0.9 9250 13.2 55.8 330 12 6 -0.8 -0.4 19.4 66.9 -5.4 164 0.8 9000 12.6 54.7 330 15 8 -7.8 -4.3 18.2 64.7 -6.7 173 0.9 8750 12.1 53.8 330 16 8 -6.1 -3.4 16.9 62.5 -8.1 183 0.9 8500 11.5 52.7 330 18 9 -6.3 -3.4 15.7 60.3 -9.4 193 1.0 8250 10.9 51.6 330 20 10 -8.7 -4.8 14.5 58.0 -10.7 203 1.0 8000 10.2 50.4 330 19 10 -8.2 -4.5 13.0 55.4 -12.2 218 1.1 7750 9.8 49.6 330 15 8 -0.9 -0.5 11.9 53.5 -13.4 221 1.1 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 * * * * * * 07/07/2024 at 0900 MDT | 07/07/2024 at 1200 MDT | CAPE... +102.1 LI... -0.2 | CAPE... +263.3 LI... -0.1 CINH... -146.0 K Index... +11.6 | CINH... -91.6 K Index... +8.7 | 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 -56.7 -70.1 280 24 13 2.8 1.5 | -56.1 -69.0 285 24 12 2.2 1.2 45000 -53.1 -63.6 280 37 19 1.2 0.7 | -53.5 -64.3 290 37 19 0.1 0.1 40000 -51.0 -59.8 290 53 27 3.3 1.8 | -53.0 -63.4 290 50 26 4.5 2.5 38000 -49.2 -56.6 290 51 26 3.1 1.7 | -50.6 -59.1 295 49 25 4.1 2.2 36000 -47.3 -53.1 295 49 25 3.1 1.7 | -48.2 -54.8 300 48 25 4.2 2.3 34000 -44.2 -47.6 300 46 24 6.3 3.4 | -44.3 -47.7 305 47 24 7.4 4.1 32000 -40.4 -40.7 310 42 22 6.3 3.4 | -39.8 -39.6 305 45 23 7.4 4.1 30000 -35.9 -32.6 310 41 21 8.2 4.5 | -35.2 -31.4 305 42 22 7.8 4.3 29000 -33.4 -28.1 315 41 21 8.2 4.5 | -32.9 -27.2 305 40 21 7.8 4.3 28000 -30.9 -23.6 315 40 21 8.2 4.5 | -30.5 -22.9 305 38 20 7.8 4.3 27000 -28.4 -19.1 315 39 20 8.6 4.7 | -28.1 -18.6 305 37 19 8.1 4.5 26000 -25.8 -14.4 315 38 19 8.6 4.7 | -25.7 -14.3 300 35 18 8.1 4.5 25000 -23.2 -9.8 310 36 19 8.6 4.7 | -23.3 -9.9 300 34 17 8.1 4.4 24000 -20.7 -5.3 310 35 18 7.7 4.2 | -20.7 -5.3 300 33 17 8.7 4.8 23000 -17.9 -0.2 310 34 18 7.7 4.2 | -17.4 0.7 300 32 16 8.7 4.8 22000 -15.5 4.1 310 34 17 7.4 4.0 | -14.8 5.4 300 31 16 8.2 4.5 21000 -13.7 7.3 310 32 16 5.8 3.2 | -12.8 9.0 300 31 16 6.4 3.5 20000 -12.0 10.4 305 30 15 5.9 3.2 | -10.9 12.4 305 33 17 6.4 3.5 19500 -11.1 12.0 305 29 15 5.9 3.2 | -10.0 14.0 305 33 17 6.5 3.6 19000 -10.2 13.6 305 27 14 6.2 3.4 | -9.1 15.6 305 33 17 5.1 2.8 18500 -9.3 15.3 305 25 13 6.3 3.5 | -8.4 16.9 305 31 16 5.2 2.9 18000 -8.4 16.9 305 22 11 6.7 3.7 | -7.6 18.3 305 30 15 5.7 3.1 17500 -7.4 18.7 305 21 11 7.4 4.1 | -6.7 19.9 305 29 15 6.5 3.5 17000 -6.3 20.7 300 19 10 7.3 4.0 | -5.8 21.6 305 27 14 6.5 3.5 16500 -5.1 22.8 300 18 9 9.5 5.2 | -4.8 23.4 300 26 13 8.3 4.6 16000 -3.7 25.3 300 18 9 9.4 5.1 | -3.6 25.5 300 24 12 8.2 4.5 15500 -2.3 27.9 300 17 9 9.2 5.1 | -2.4 27.7 300 23 12 8.9 4.9 15000 -1.0 30.2 300 17 9 9.2 5.1 | -1.0 30.2 295 22 11 9.3 5.1 14500 0.3 32.5 300 17 9 9.3 5.1 | 0.3 32.5 295 21 11 9.3 5.1 14000 1.7 35.1 300 17 9 9.6 5.2 | 1.7 35.1 295 20 10 9.3 5.1 13500 3.2 37.8 300 16 8 9.6 5.3 | 3.1 37.6 295 18 10 9.4 5.1 13000 4.6 40.3 300 16 8 10.1 5.6 | 4.6 40.3 290 17 9 10.4 5.7 12500 6.1 43.0 305 15 8 9.5 5.2 | 6.0 42.8 290 16 8 8.3 4.5 12000 7.4 45.3 310 15 8 8.9 4.9 | 7.3 45.1 295 15 8 9.4 5.1 11750 8.1 46.6 310 16 8 8.8 4.8 | 8.0 46.4 295 14 7 9.0 5.0 11500 8.8 47.8 310 16 8 9.8 5.4 | 8.7 47.7 295 13 7 9.8 5.4 11250 9.5 49.1 315 16 8 7.8 4.3 | 9.3 48.7 295 13 7 6.6 3.6 11000 9.9 49.8 315 16 8 5.6 3.1 | 9.6 49.3 300 13 7 3.8 2.1 10750 10.4 50.7 315 17 9 5.6 3.1 | 9.9 49.8 305 13 7 3.8 2.1 10500 10.8 51.4 320 18 9 7.8 4.3 | 10.2 50.4 315 13 7 6.4 3.5 10250 11.3 52.3 320 18 9 4.5 2.5 | 10.6 51.1 315 13 7 2.5 1.4 10000 11.3 52.3 325 19 10 -0.6 -0.3 | 10.4 50.7 325 14 7 -3.8 -2.1 9750 11.3 52.3 325 20 10 0.5 0.3 | 10.0 50.0 335 15 8 -2.1 -1.1 9500 11.3 52.3 325 21 11 0.4 0.2 | 9.7 49.5 345 17 9 -3.5 -1.9 9250 11.2 52.2 330 22 11 -0.5 -0.3 | 9.5 49.1 350 19 10 4.6 2.5 9000 11.1 52.0 330 22 12 -0.9 -0.5 | 10.3 50.5 350 19 10 11.4 6.3 8750 10.9 51.6 330 23 12 -0.4 -0.2 | 10.9 51.6 355 19 10 9.1 5.0 8500 10.8 51.4 330 23 12 0.2 0.1 | 11.6 52.9 355 19 10 9.9 5.4 8250 10.9 51.6 330 23 12 5.9 3.2 | 12.4 54.3 355 19 10 12.2 6.7 8000 11.7 53.1 330 22 11 16.8 9.2 | 13.6 56.5 355 19 10 21.8 11.9 7750 13.3 55.9 335 19 10 24.4 13.4 | 15.6 60.1 355 17 9 32.4 17.8 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 07/07/2024 at 1500 MDT | 07/07/2024 at 1800 MDT | CAPE... +661.7 LI... -2.9 | CAPE... +572.1 LI... -2.0 CINH... -52.0 K Index... +25.6 | CINH... -4.6 K Index... +26.6 | 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 -55.1 -67.2 285 21 11 2.3 1.2 | -55.6 -68.1 280 19 10 2.5 1.4 45000 -53.0 -63.4 290 34 18 -1.3 -0.7 | -53.0 -63.4 285 30 15 -0.5 -0.3 40000 -54.4 -65.9 295 46 24 5.9 3.2 | -53.4 -64.1 295 43 22 4.9 2.7 38000 -51.3 -60.3 295 45 23 5.1 2.8 | -50.8 -59.4 295 42 21 4.3 2.4 36000 -48.3 -54.9 290 45 23 5.2 2.9 | -48.2 -54.8 295 41 21 4.4 2.4 34000 -44.1 -47.4 290 44 23 7.5 4.1 | -44.3 -47.7 295 40 21 7.3 4.0 32000 -39.7 -39.5 295 43 22 7.5 4.1 | -39.9 -39.8 295 39 20 7.3 4.0 30000 -34.9 -30.8 295 42 22 8.1 4.4 | -35.2 -31.4 295 39 20 8.3 4.5 29000 -32.5 -26.5 295 42 22 8.1 4.4 | -32.7 -26.9 295 39 20 8.3 4.5 28000 -30.1 -22.2 295 42 21 8.1 4.4 | -30.2 -22.4 295 40 21 8.3 4.5 27000 -27.7 -17.9 295 41 21 8.0 4.4 | -27.8 -18.0 290 39 20 8.0 4.4 26000 -25.3 -13.5 295 40 20 8.0 4.4 | -25.4 -13.7 290 39 20 8.0 4.4 25000 -22.9 -9.2 290 38 20 8.0 4.4 | -22.9 -9.2 290 38 20 8.1 4.4 24000 -20.8 -5.4 290 38 19 6.2 3.4 | -20.7 -5.3 290 38 19 6.9 3.8 23000 -18.9 -2.0 290 38 19 6.2 3.4 | -18.2 -0.8 280 38 19 7.0 3.9 22000 -16.6 2.1 290 37 19 6.6 3.6 | -16.1 3.0 275 38 19 7.5 4.1 21000 -14.5 5.9 285 36 18 7.5 4.1 | -13.8 7.2 275 36 19 8.3 4.5 20000 -12.3 9.9 280 34 17 7.7 4.2 | -11.3 11.7 280 35 18 8.3 4.6 19500 -11.2 11.8 275 33 17 7.6 4.2 | -10.1 13.8 280 34 17 8.5 4.6 19000 -10.0 14.0 275 32 17 9.2 5.1 | -9.0 15.8 280 33 17 7.9 4.3 18500 -8.7 16.3 275 31 16 9.2 5.0 | -7.8 18.0 280 31 16 8.0 4.4 18000 -7.4 18.7 275 29 15 9.2 5.0 | -6.6 20.1 280 30 16 8.1 4.5 17500 -6.1 21.0 275 28 15 9.1 5.0 | -5.4 22.3 280 28 15 8.3 4.5 17000 -4.7 23.5 275 27 14 9.1 5.0 | -4.2 24.4 280 26 13 8.4 4.6 16500 -3.4 25.9 275 26 13 9.3 5.1 | -3.2 26.2 275 24 12 6.6 3.6 16000 -2.0 28.4 275 24 12 9.3 5.1 | -2.2 28.0 270 22 11 6.8 3.7 15500 -0.7 30.7 275 23 12 8.6 4.7 | -1.2 29.8 265 20 10 6.1 3.4 15000 0.5 32.9 270 21 11 8.3 4.6 | -0.4 31.3 260 19 10 5.9 3.2 14500 1.7 35.1 270 19 10 8.0 4.4 | 0.4 32.7 255 18 9 5.1 2.8 14000 2.8 37.0 265 17 8 7.6 4.2 | 1.0 33.8 260 15 8 3.9 2.2 13500 3.9 39.0 265 14 7 7.3 4.0 | 1.5 34.7 265 12 6 4.0 2.2 13000 4.8 40.6 270 11 6 5.3 2.9 | 2.0 35.6 290 8 4 4.2 2.3 12500 5.4 41.7 280 8 4 3.3 1.8 | 2.7 36.9 320 7 4 5.8 3.2 12000 5.5 41.9 320 6 3 -0.6 -0.4 | 3.7 38.7 350 7 3 8.1 4.5 11750 5.5 41.9 350 6 3 0.2 0.1 | 4.2 39.6 005 7 3 8.0 4.4 11500 5.4 41.7 010 9 4 0.4 0.2 | 4.8 40.6 015 7 4 6.7 3.7 11250 5.4 41.7 020 10 5 5.5 3.0 | 5.2 41.4 025 9 4 6.1 3.4 11000 6.1 43.0 025 11 6 9.6 5.3 | 5.7 42.3 030 9 5 6.8 3.8 10750 6.7 44.1 025 12 6 7.6 4.2 | 6.2 43.2 030 10 5 6.7 3.7 10500 7.3 45.1 030 12 6 11.6 6.4 | 6.7 44.1 035 10 5 6.7 3.7 10250 8.3 46.9 030 13 7 12.2 6.7 | 7.2 45.0 035 11 6 8.8 4.9 10000 9.0 48.2 030 13 7 8.9 4.9 | 8.0 46.4 035 11 6 10.4 5.7 9750 9.8 49.6 030 13 7 9.9 5.4 | 8.7 47.7 035 11 6 10.2 5.6 9500 10.5 50.9 030 13 7 9.3 5.1 | 9.5 49.1 035 11 6 9.3 5.1 9250 11.2 52.2 030 13 7 9.4 5.2 | 10.1 50.2 035 11 6 8.6 4.7 9000 11.9 53.4 030 13 7 10.7 5.9 | 10.8 51.4 035 11 6 10.5 5.8 8750 12.8 55.0 030 13 7 11.2 6.2 | 11.7 53.1 035 11 6 11.6 6.4 8500 13.6 56.5 030 13 7 10.8 6.0 | 12.5 54.5 035 11 6 10.6 5.8 8250 14.4 57.9 035 13 7 11.1 6.1 | 13.2 55.8 035 11 6 8.9 4.9 8000 15.4 59.7 035 13 7 19.7 10.8 | 13.9 57.0 035 11 6 11.5 6.3 7750 17.4 63.3 035 12 6 32.6 17.9 | 15.0 59.0 035 10 5 17.1 9.4 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 ________________________________________________________________________________ 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