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Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
894 UXUS97 KPUB 111209 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0609 MDT Thursday, July 11, 2024 This forecast is for the Air Force Academy for Thursday, July 11, 2024: If the trigger temperature of 75.8 F/24.3 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1790 ft/min (9.1 m/s) Maximum height of thermals.................. 25459 ft MSL (17849 ft AGL) Forecast maximum temperature................... 90.0 F/32.7 C Time of trigger temperature.................... 0930 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................. 22504 ft MSL (14895 ft AGL) Thermal soaring outlook for Friday 07/12....... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:43:52 / 20:25:59 MDT Total possible sunshine........... 14 hr 42 min 8 sec (882 min 8 sec) Altitude of sun at 13:04:56 MDT... 72.94 degrees Upper air data from numerical model forecast valid on 07/11/2024 at 0600 MDT Freezing level.................. 16167 ft MSL (8557 ft AGL) Convective condensation level... 17718 ft MSL (10108 ft AGL) Lifted condensation level....... 20223 ft MSL (12614 ft AGL) Lifted index.................... -6.0 K index......................... +20.3 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 -59.0 -74.2 015 23 12 2.1 1.2 M M M M M 45000 -55.9 -68.6 015 30 15 2.1 1.1 M M M M M 40000 -52.4 -62.3 360 28 14 4.7 2.6 M M M M M 38000 -49.2 -56.6 360 28 14 4.7 2.6 M M M M M 36000 -46.4 -51.5 360 27 14 5.1 2.8 M M M M M 34000 -42.0 -43.6 355 25 13 7.6 4.1 M M M M M 32000 -37.4 -35.3 345 23 12 7.4 4.0 M M M M M 30000 -32.4 -26.3 350 23 12 8.6 4.7 35.8 96.5 2.8 M M 29000 -29.8 -21.6 350 23 12 8.6 4.7 35.4 95.8 2.5 M M 28000 -27.3 -17.1 355 23 12 7.4 4.0 35.0 95.1 2.2 M M 27000 -25.2 -13.4 350 21 11 7.0 3.9 33.9 93.0 1.3 M M 26000 -23.1 -9.6 345 18 10 7.1 3.9 32.9 91.2 0.5 M M 25000 -21.0 -5.8 335 16 8 7.0 3.8 32.0 89.7 -0.3 1755 8.9 24000 -19.1 -2.4 345 17 9 6.5 3.6 30.8 87.4 -1.3 1668 8.5 23000 -17.2 1.0 350 19 10 6.5 3.6 29.6 85.3 -2.4 1581 8.0 22000 -14.7 5.5 355 21 11 8.1 4.4 28.4 83.1 -3.5 1470 7.5 21000 -12.3 9.9 355 20 10 8.2 4.5 27.8 82.0 -4.2 1368 7.0 20000 -9.9 14.2 360 19 10 8.3 4.5 27.3 81.1 -4.7 1267 6.4 19500 -8.7 16.3 360 19 10 8.6 4.7 27.1 80.7 -5.0 1216 6.2 19000 -7.4 18.7 360 17 9 9.0 4.9 26.9 80.5 -5.2 1162 5.9 18500 -6.1 21.0 005 15 7 9.0 4.9 26.8 80.2 -5.3 1107 5.6 18000 -4.7 23.5 005 13 7 8.8 4.8 26.7 80.0 -5.5 1052 5.3 17500 -3.4 25.9 010 11 6 8.8 4.8 26.5 79.7 -5.6 997 5.1 17000 -2.1 28.2 010 10 5 8.7 4.8 26.4 79.5 -5.8 943 4.8 16500 -0.8 30.6 015 9 5 8.6 4.7 26.2 79.1 -6.0 889 4.5 16000 0.5 32.9 015 8 4 8.6 4.7 26.0 78.7 -6.2 836 4.2 15500 1.8 35.2 010 7 4 9.4 5.2 25.9 78.5 -6.4 781 4.0 15000 3.2 37.8 005 7 4 9.4 5.1 25.8 78.4 -6.5 726 3.7 14500 4.6 40.3 355 6 3 9.3 5.1 25.7 78.3 -6.6 670 3.4 14000 6.0 42.8 345 6 3 9.3 5.1 25.6 78.2 -6.7 613 3.1 13500 7.3 45.1 335 5 3 8.4 4.6 25.6 78.0 -6.9 558 2.8 13000 8.5 47.3 310 5 2 8.4 4.6 25.3 77.5 -7.2 509 2.6 12500 9.8 49.6 290 5 2 9.7 5.3 25.2 77.3 -7.4 454 2.3 12000 11.2 52.2 270 5 3 9.9 5.4 25.2 77.3 -7.5 396 2.0 11750 11.9 53.4 265 6 3 9.3 5.1 25.2 77.4 -7.5 368 1.9 11500 12.5 54.5 260 7 3 7.8 4.3 25.1 77.2 -7.6 342 1.7 11250 13.1 55.6 260 7 4 7.3 4.0 24.9 76.8 -7.8 318 1.6 11000 13.6 56.5 260 8 4 7.7 4.2 24.7 76.5 -8.1 295 1.5 10750 14.2 57.6 255 9 4 7.0 3.9 24.6 76.2 -8.3 271 1.4 10500 14.7 58.5 255 9 5 9.5 5.2 24.4 75.9 -8.5 247 1.3 10250 15.4 59.7 255 10 5 8.3 4.6 24.4 76.0 -8.5 218 1.1 10000 15.8 60.4 255 11 6 5.2 2.9 24.1 75.4 -8.8 198 1.0 9750 16.3 61.3 255 12 6 5.9 3.2 23.8 74.9 -9.2 179 0.9 9500 16.7 62.1 250 13 7 6.3 3.5 23.5 74.4 -9.5 159 0.8 9250 17.1 62.8 255 13 7 5.3 2.9 23.3 73.9 -9.8 138 0.7 9000 17.4 63.3 255 15 8 3.2 1.8 22.8 73.1 -10.3 123 0.6 8750 17.6 63.7 255 16 8 3.5 1.9 22.3 72.2 -10.9 110 0.6 8500 17.8 64.0 255 17 9 2.6 1.4 21.9 71.3 -11.4 96 0.5 8250 17.9 64.2 255 17 9 -0.1 -0.1 21.2 70.2 -12.1 86 0.4 8000 17.6 63.7 255 17 9 -8.4 -4.6 20.2 68.4 -13.1 87 0.4 7750 16.2 61.2 255 16 8 -30.4 -16.7 18.1 64.7 -15.2 120 0.6 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 * * * * * * 07/11/2024 at 0900 MDT | 07/11/2024 at 1200 MDT | CAPE... +419.9 LI... -1.8 | CAPE... +596.7 LI... -2.1 CINH... -98.8 K Index... +26.7 | CINH... -0.8 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 -59.0 -74.2 015 21 11 2.3 1.3 | -58.9 -74.0 010 20 10 2.8 1.6 45000 -55.7 -68.3 010 28 15 2.1 1.1 | -55.2 -67.4 360 27 14 1.6 0.9 40000 -51.8 -61.2 005 37 19 5.1 2.8 | -51.9 -61.4 360 35 18 5.0 2.8 38000 -48.8 -55.8 010 36 19 5.1 2.8 | -48.9 -56.0 005 35 18 5.0 2.7 36000 -45.8 -50.4 010 36 19 5.4 2.9 | -45.9 -50.6 005 35 18 5.4 3.0 34000 -41.4 -42.5 010 32 16 7.4 4.1 | -41.5 -42.7 005 33 17 7.4 4.1 32000 -36.9 -34.4 005 27 14 7.3 4.0 | -37.0 -34.6 005 31 16 7.5 4.1 30000 -32.3 -26.1 360 24 13 7.8 4.3 | -32.2 -26.0 010 28 14 8.0 4.4 29000 -30.0 -22.0 355 23 12 7.8 4.3 | -29.8 -21.6 010 26 13 8.0 4.4 28000 -27.7 -17.9 350 22 11 6.9 3.8 | -27.4 -17.3 015 24 12 7.7 4.2 27000 -25.7 -14.3 345 20 11 6.7 3.7 | -25.1 -13.2 010 22 11 7.7 4.2 26000 -23.7 -10.7 345 19 10 6.8 3.7 | -22.8 -9.0 010 20 10 7.7 4.2 25000 -21.7 -7.1 340 17 9 6.9 3.8 | -20.5 -4.9 005 19 10 7.3 4.0 24000 -19.7 -3.5 340 18 9 7.0 3.9 | -18.7 -1.7 355 19 10 6.1 3.3 23000 -17.1 1.2 345 20 10 7.1 3.9 | -16.5 2.3 350 19 10 6.2 3.4 22000 -15.0 5.0 345 21 11 8.3 4.6 | -14.6 5.7 345 20 10 8.8 4.8 21000 -12.5 9.5 355 21 11 8.3 4.6 | -12.1 10.2 350 20 10 8.8 4.8 20000 -10.1 13.8 360 21 11 8.3 4.6 | -9.5 14.9 350 20 10 8.8 4.8 19500 -8.9 16.0 005 21 11 8.5 4.7 | -8.3 17.1 355 20 10 7.4 4.1 19000 -7.6 18.3 005 19 10 8.6 4.7 | -7.3 18.9 355 18 9 6.4 3.5 18500 -6.4 20.5 005 17 9 8.6 4.7 | -6.4 20.5 360 17 9 6.1 3.4 18000 -5.1 22.8 005 15 8 8.8 4.8 | -5.2 22.6 360 15 8 10.0 5.5 17500 -3.8 25.2 360 12 6 8.8 4.8 | -3.7 25.3 355 13 7 9.7 5.3 17000 -2.5 27.5 355 10 5 9.1 5.0 | -2.3 27.9 350 11 6 9.4 5.1 16500 -1.1 30.0 355 9 4 9.3 5.1 | -1.0 30.2 345 9 5 9.2 5.1 16000 0.3 32.5 350 7 4 9.3 5.1 | 0.3 32.5 330 7 4 9.3 5.1 15500 1.6 34.9 350 6 3 9.1 5.0 | 1.7 35.1 320 6 3 9.5 5.2 15000 3.0 37.4 345 5 3 9.1 5.0 | 3.1 37.6 315 5 3 9.5 5.2 14500 4.4 39.9 335 4 2 9.1 5.0 | 4.5 40.1 305 5 2 9.3 5.1 14000 5.7 42.3 330 4 2 9.1 5.0 | 5.9 42.6 305 4 2 9.3 5.1 13500 7.1 44.8 320 4 2 9.0 4.9 | 7.3 45.1 300 4 2 9.5 5.2 13000 8.4 47.1 310 4 2 9.4 5.1 | 8.7 47.7 300 4 2 9.8 5.4 12500 10.0 50.0 305 4 2 10.5 5.7 | 10.2 50.4 300 4 2 10.4 5.7 12000 11.4 52.5 295 4 2 9.7 5.3 | 11.8 53.2 295 3 2 10.2 5.6 11750 12.1 53.8 295 4 2 9.0 5.0 | 12.5 54.5 295 3 2 10.0 5.5 11500 12.8 55.0 290 4 2 8.9 4.9 | 13.3 55.9 295 3 2 9.8 5.4 11250 13.5 56.3 290 4 2 9.5 5.2 | 14.0 57.2 290 3 2 9.8 5.4 11000 14.2 57.6 290 4 2 9.6 5.3 | 14.7 58.5 290 3 2 9.8 5.4 10750 14.9 58.8 290 4 2 9.3 5.1 | 15.5 59.9 290 3 2 9.7 5.3 10500 15.6 60.1 290 4 2 10.6 5.8 | 16.2 61.2 290 3 2 10.1 5.5 10250 16.3 61.3 290 5 3 8.8 4.8 | 16.9 62.4 285 3 1 10.0 5.5 10000 16.8 62.2 290 6 3 6.6 3.6 | 17.7 63.9 285 3 1 9.6 5.3 9750 17.4 63.3 290 6 3 6.5 3.6 | 18.4 65.1 285 3 1 9.8 5.4 9500 17.9 64.2 285 7 4 9.0 5.0 | 19.1 66.4 285 3 1 9.4 5.2 9250 18.6 65.5 285 7 4 7.9 4.3 | 19.8 67.6 285 3 1 9.6 5.3 9000 18.9 66.0 280 8 4 3.2 1.8 | 20.6 69.1 280 3 1 10.2 5.6 8750 19.1 66.4 275 9 5 3.5 1.9 | 21.3 70.3 280 3 1 10.1 5.5 8500 19.3 66.7 270 10 5 3.4 1.9 | 22.1 71.8 280 3 1 10.4 5.7 8250 19.5 67.1 270 11 6 3.5 1.9 | 22.9 73.2 280 2 1 11.3 6.2 8000 19.7 67.5 265 12 6 1.8 1.0 | 23.7 74.7 275 2 1 10.2 5.6 7750 19.7 67.5 265 11 6 1.9 1.0 | 24.6 76.3 275 2 1 15.6 8.5 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 07/11/2024 at 1500 MDT | 07/11/2024 at 1800 MDT | CAPE... +604.2 LI... -2.4 | CAPE... +559.8 LI... -2.6 CINH... -1.2 K Index... +30.9 | CINH... -20.2 K Index... +28.5 | 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 -59.3 -74.7 015 18 9 3.0 1.7 | -59.7 -75.5 015 15 8 3.2 1.8 45000 -55.2 -67.4 360 24 12 1.8 1.0 | -56.2 -69.2 355 22 11 0.5 0.3 40000 -51.8 -61.2 355 36 18 5.1 2.8 | -53.8 -64.8 350 35 18 7.3 4.0 38000 -48.7 -55.7 350 36 19 5.2 2.8 | -49.4 -56.9 345 33 17 7.2 4.0 36000 -45.7 -50.3 350 37 19 5.1 2.8 | -45.1 -49.2 345 32 16 7.6 4.2 34000 -41.4 -42.5 355 36 19 7.3 4.0 | -40.1 -40.2 350 31 16 8.2 4.5 32000 -36.5 -33.7 360 36 18 7.7 4.2 | -35.2 -31.4 355 31 16 8.8 4.8 30000 -31.8 -25.2 005 32 16 8.0 4.4 | -30.7 -23.3 360 32 16 7.4 4.1 29000 -29.4 -20.9 005 30 15 8.0 4.4 | -28.5 -19.3 360 32 16 7.4 4.1 28000 -26.9 -16.4 005 28 14 8.6 4.7 | -26.2 -15.2 005 32 16 7.9 4.3 27000 -24.4 -11.9 005 25 13 8.5 4.7 | -23.8 -10.8 360 30 15 8.0 4.4 26000 -21.8 -7.2 360 22 11 8.5 4.7 | -21.4 -6.5 360 28 14 8.0 4.4 25000 -19.3 -2.7 360 19 10 7.0 3.9 | -19.0 -2.2 360 26 13 7.7 4.2 24000 -17.6 0.3 355 19 10 5.7 3.1 | -16.4 2.5 355 23 12 7.0 3.8 23000 -15.9 3.4 350 18 9 5.7 3.1 | -14.3 6.3 350 20 10 7.0 3.8 22000 -14.2 6.4 345 18 9 7.1 3.9 | -12.3 9.9 345 18 9 5.7 3.1 21000 -12.0 10.4 350 18 9 7.9 4.3 | -10.6 12.9 340 16 8 5.9 3.2 20000 -9.7 14.5 355 18 9 8.2 4.5 | -9.0 15.8 335 14 7 6.1 3.4 19500 -8.6 16.5 360 18 9 8.4 4.6 | -8.1 17.4 330 13 6 7.7 4.2 19000 -6.7 19.9 360 16 8 9.3 5.1 | -6.8 19.8 325 12 6 9.1 5.0 18500 -5.4 22.3 360 14 7 9.3 5.1 | -5.5 22.1 325 11 6 9.3 5.1 18000 -4.1 24.6 360 13 7 9.0 4.9 | -4.2 24.4 325 10 5 8.8 4.8 17500 -2.8 27.0 360 12 6 9.0 5.0 | -2.9 26.8 325 9 5 8.9 4.9 17000 -1.5 29.3 360 11 6 9.5 5.2 | -1.7 28.9 320 8 4 9.0 4.9 16500 -0.0 32.0 360 10 5 9.6 5.3 | -0.3 31.5 325 7 4 9.0 4.9 16000 1.4 34.5 360 10 5 9.6 5.3 | 1.0 33.8 330 6 3 9.0 4.9 15500 2.8 37.0 360 9 5 9.5 5.2 | 2.3 36.1 335 5 3 9.5 5.2 15000 4.2 39.6 360 9 5 9.6 5.3 | 3.7 38.7 345 5 3 9.5 5.2 14500 5.6 42.1 005 8 4 9.2 5.1 | 5.1 41.2 350 5 3 9.0 4.9 14000 7.0 44.6 005 7 4 9.3 5.1 | 6.5 43.7 360 5 3 9.0 4.9 13500 8.4 47.1 005 6 3 9.3 5.1 | 7.8 46.0 005 6 3 8.9 4.9 13000 9.8 49.6 010 4 2 10.1 5.5 | 9.1 48.4 010 7 3 8.8 4.8 12500 11.4 52.5 010 4 2 10.3 5.6 | 10.4 50.7 010 7 4 8.9 4.9 12000 12.9 55.2 020 3 2 9.8 5.4 | 11.8 53.2 010 8 4 9.7 5.3 11750 13.6 56.5 025 2 1 9.3 5.1 | 12.5 54.5 010 8 4 9.0 4.9 11500 14.3 57.7 030 2 1 9.5 5.2 | 13.1 55.6 010 8 4 8.4 4.6 11250 15.0 59.0 035 2 1 10.1 5.5 | 13.8 56.8 010 8 4 8.9 4.9 11000 15.8 60.4 040 2 1 10.0 5.5 | 14.4 57.9 010 8 4 9.0 5.0 10750 16.5 61.7 045 2 1 9.8 5.4 | 15.1 59.2 010 9 4 8.8 4.8 10500 17.2 63.0 055 2 1 10.6 5.8 | 15.8 60.4 010 9 5 9.6 5.2 10250 18.1 64.6 065 1 1 10.5 5.8 | 16.5 61.7 015 9 5 9.9 5.4 10000 18.8 65.8 070 1 1 9.6 5.3 | 17.2 63.0 015 9 5 9.2 5.1 9750 19.5 67.1 080 1 1 10.3 5.6 | 17.9 64.2 015 9 5 9.8 5.4 9500 20.2 68.4 085 1 1 8.4 4.6 | 18.6 65.5 020 10 5 8.3 4.5 9250 20.8 69.4 095 2 1 8.8 4.9 | 19.2 66.6 020 10 5 8.7 4.8 9000 21.6 70.9 100 2 1 11.0 6.0 | 19.9 67.8 020 10 5 10.6 5.8 8750 22.4 72.3 105 2 1 10.6 5.8 | 20.7 69.3 025 10 5 10.6 5.8 8500 23.2 73.8 110 2 1 10.4 5.7 | 21.5 70.7 025 10 5 9.8 5.4 8250 24.0 75.2 115 2 1 10.7 5.9 | 22.1 71.8 030 11 5 8.8 4.8 8000 24.8 76.6 120 2 1 10.3 5.6 | 22.8 73.0 030 11 6 9.1 5.0 7750 25.7 78.3 125 2 1 16.7 9.2 | 23.5 74.3 030 11 6 10.7 5.9 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