Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
863 UXUS97 KPUB 041211 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0611 MDT Thursday, July 4, 2024 This forecast is for the Air Force Academy for Thursday, July 4, 2024: If the trigger temperature of 70.0 F/21.1 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 887 ft/min (4.5 m/s) Maximum height of thermals.................. 17162 ft MSL (9550 ft AGL) Forecast maximum temperature................... 78.0 F/26.0 C Time of trigger temperature.................... 1045 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................. 13970 ft MSL (6359 ft AGL) Thermal soaring outlook for Friday 07/05....... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:39:28 / 20:28:17 MDT Total possible sunshine........... 14 hr 48 min 49 sec (888 min 49 sec) Altitude of sun at 13:03:52 MDT... 73.78 degrees Upper air data from numerical model forecast valid on 07/04/2024 at 0600 MDT Freezing level.................. 15505 ft MSL (7893 ft AGL) Convective condensation level... 18641 ft MSL (11029 ft AGL) Lifted condensation level....... 18572 ft MSL (10961 ft AGL) Lifted index.................... +2.0 K index......................... -18.2 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 -77.6 275 39 20 2.6 1.4 M M M M M 45000 -56.2 -69.2 275 59 30 4.2 2.3 M M M M M 40000 -49.8 -57.6 270 68 35 5.3 2.9 M M M M M 38000 -46.2 -51.2 270 67 34 5.3 2.9 M M M M M 36000 -43.0 -45.4 270 66 34 5.4 2.9 M M M M M 34000 -38.9 -38.0 275 64 33 7.0 3.9 M M M M M 32000 -34.7 -30.5 280 62 32 7.0 3.8 M M M M M 30000 -30.2 -22.4 285 61 31 7.5 4.1 38.8 101.8 10.3 M M 29000 -28.0 -18.4 285 60 31 7.5 4.1 38.0 100.3 9.8 M M 28000 -25.7 -14.3 285 59 30 7.9 4.3 37.3 99.1 9.3 M M 27000 -23.2 -9.8 285 58 30 8.4 4.6 36.6 97.9 8.9 M M 26000 -20.7 -5.3 285 58 30 8.4 4.6 36.1 96.9 8.6 M M 25000 -18.2 -0.8 290 57 29 8.8 4.8 35.7 96.2 8.3 M M 24000 -16.5 2.3 290 54 28 4.5 2.5 34.1 93.4 7.1 M M 23000 -15.2 4.6 290 49 25 4.5 2.5 32.2 90.0 5.6 M M 22000 -13.5 7.7 290 44 23 5.2 2.9 30.1 86.1 3.8 M M 21000 -11.7 10.9 290 40 21 5.8 3.2 28.6 83.5 2.6 M M 20000 -10.0 14.0 290 36 19 5.9 3.2 27.3 81.1 1.5 M M 19500 -9.1 15.6 290 34 18 5.9 3.3 26.7 80.0 0.9 M M 19000 -7.9 17.8 295 33 17 9.4 5.1 26.3 79.4 0.7 M M 18500 -6.6 20.1 295 32 17 9.1 5.0 26.2 79.2 0.6 M M 18000 -5.2 22.6 295 32 16 8.3 4.6 26.1 79.0 0.5 M M 17500 -4.0 24.8 290 31 16 7.8 4.3 25.8 78.4 0.2 M M 17000 -2.9 26.8 290 30 15 7.7 4.2 25.5 77.8 -0.1 867 4.4 16500 -1.8 28.8 285 29 15 6.2 3.4 25.0 76.9 -0.6 822 4.2 16000 -0.9 30.4 285 29 15 6.4 3.5 24.4 75.9 -1.1 779 4.0 15500 0.0 32.0 280 28 14 6.6 3.6 23.9 75.0 -1.6 736 3.7 15000 1.0 33.8 280 28 14 6.8 3.7 23.4 74.1 -2.1 692 3.5 14500 2.0 35.6 280 27 14 7.4 4.0 22.9 73.3 -2.6 648 3.3 14000 3.1 37.6 280 26 14 7.9 4.3 22.6 72.7 -3.0 599 3.0 13500 4.3 39.7 280 26 13 7.9 4.4 22.3 72.2 -3.3 550 2.8 13000 5.4 41.7 285 24 12 7.9 4.4 22.0 71.7 -3.6 501 2.5 12500 6.5 43.7 285 21 11 8.1 4.4 21.7 71.1 -4.0 452 2.3 12000 7.9 46.2 285 19 10 10.0 5.5 21.7 71.0 -4.1 398 2.0 11750 8.6 47.5 285 18 9 10.1 5.5 21.7 71.0 -4.2 369 1.9 11500 9.3 48.7 285 17 9 7.9 4.3 21.7 71.0 -4.2 341 1.7 11250 9.7 49.5 285 16 8 5.6 3.1 21.4 70.5 -4.5 320 1.6 11000 10.1 50.2 290 15 8 5.8 3.2 21.1 69.9 -4.9 301 1.5 10750 10.5 50.9 295 15 8 5.6 3.1 20.7 69.3 -5.3 283 1.4 10500 10.9 51.6 300 15 8 6.4 3.5 20.4 68.8 -5.6 264 1.3 10250 11.2 52.2 305 14 7 2.4 1.3 20.1 68.2 -6.0 245 1.2 10000 11.1 52.0 315 15 8 -1.5 -0.8 19.3 66.7 -6.8 241 1.2 9750 11.0 51.8 320 16 8 -0.3 -0.2 18.5 65.3 -7.7 236 1.2 9500 10.9 51.6 325 18 9 -0.8 -0.4 17.7 63.9 -8.5 232 1.2 9250 10.7 51.3 330 20 10 -4.3 -2.3 16.8 62.3 -9.5 230 1.2 9000 10.2 50.4 335 22 11 -6.7 -3.7 15.6 60.1 -10.7 238 1.2 8750 9.7 49.5 335 24 12 -6.3 -3.5 14.4 57.9 -12.0 246 1.3 8500 9.2 48.6 340 26 13 -5.8 -3.2 13.2 55.7 -13.3 254 1.3 8250 8.8 47.8 340 26 14 -4.0 -2.2 12.1 53.7 -14.4 259 1.3 8000 8.6 47.5 335 25 13 -2.2 -1.2 11.1 52.0 -15.4 258 1.3 7750 8.4 47.1 330 19 10 -0.6 -0.3 10.3 50.5 -16.4 255 1.3 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 * * * * * * 07/04/2024 at 0900 MDT | 07/04/2024 at 1200 MDT | CAPE... 0.0 LI... +2.3 | CAPE... +28.2 LI... -0.5 CINH... 0.0 K Index... -12.5 | CINH... -26.0 K Index... -0.6 | 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 -61.0 -77.8 280 38 19 3.2 1.8 | -60.5 -76.9 280 37 19 2.2 1.2 45000 -55.6 -68.1 275 52 27 4.3 2.3 | -56.1 -69.0 280 52 27 4.5 2.5 40000 -49.1 -56.4 270 59 31 4.7 2.6 | -49.3 -56.7 270 60 31 4.8 2.6 38000 -46.0 -50.8 270 58 30 4.7 2.6 | -46.4 -51.5 270 58 30 4.8 2.6 36000 -43.2 -45.8 270 57 29 4.9 2.7 | -43.2 -45.8 270 56 29 5.0 2.7 34000 -39.2 -38.6 270 56 29 6.8 3.7 | -39.3 -38.7 270 56 29 6.6 3.6 32000 -35.1 -31.2 270 56 29 6.7 3.7 | -35.3 -31.5 270 56 29 6.5 3.6 30000 -30.6 -23.1 275 55 28 7.6 4.2 | -31.0 -23.8 270 55 28 7.4 4.1 29000 -28.3 -18.9 275 55 28 7.6 4.2 | -28.7 -19.7 270 54 28 7.4 4.1 28000 -26.1 -15.0 280 55 28 8.0 4.4 | -26.5 -15.7 275 53 27 7.8 4.3 27000 -23.6 -10.5 280 54 28 8.3 4.6 | -24.1 -11.4 275 52 27 8.0 4.4 26000 -21.1 -6.0 280 53 27 8.3 4.6 | -21.7 -7.1 275 51 26 8.0 4.4 25000 -18.6 -1.5 280 52 27 8.5 4.7 | -19.3 -2.7 280 50 26 8.0 4.4 24000 -16.6 2.1 285 49 25 5.9 3.2 | -17.1 1.2 280 49 25 7.2 4.0 23000 -14.9 5.2 285 46 23 5.9 3.3 | -14.9 5.2 280 47 24 7.2 4.0 22000 -12.7 9.1 285 41 21 5.0 2.8 | -12.8 9.0 285 46 24 7.1 3.9 21000 -11.3 11.7 285 36 19 4.5 2.5 | -11.2 11.8 285 40 20 3.8 2.1 20000 -10.0 14.0 285 31 16 4.5 2.5 | -10.0 14.0 280 34 18 3.8 2.1 19500 -9.3 15.3 285 29 15 4.9 2.7 | -9.5 14.9 275 32 16 4.4 2.4 19000 -8.3 17.1 285 28 14 7.4 4.1 | -8.5 16.7 275 30 16 7.3 4.0 18500 -7.3 18.9 285 27 14 7.2 3.9 | -7.5 18.5 275 30 15 7.1 3.9 18000 -6.1 21.0 290 27 14 8.9 4.9 | -6.4 20.5 280 29 15 7.7 4.2 17500 -4.7 23.5 290 26 14 9.5 5.2 | -5.2 22.6 280 29 15 7.9 4.3 17000 -3.3 26.1 295 26 14 9.3 5.1 | -4.1 24.6 285 29 15 7.9 4.4 16500 -1.9 28.6 295 26 13 8.6 4.7 | -2.9 26.8 285 29 15 8.0 4.4 16000 -0.6 30.9 290 26 13 8.9 4.9 | -1.7 28.9 290 29 15 8.0 4.4 15500 0.6 33.1 290 25 13 6.7 3.7 | -0.6 30.9 290 28 15 7.8 4.3 15000 1.6 34.9 290 25 13 6.7 3.7 | 0.6 33.1 285 27 14 7.9 4.3 14500 2.6 36.7 290 24 12 6.0 3.3 | 1.7 35.1 285 25 13 7.5 4.1 14000 3.4 38.1 290 23 12 5.7 3.1 | 2.7 36.9 280 23 12 7.5 4.1 13500 4.2 39.6 290 22 11 5.8 3.2 | 3.7 38.7 275 21 11 7.2 4.0 13000 5.0 41.0 290 20 11 5.9 3.3 | 4.6 40.3 270 18 9 7.1 3.9 12500 5.8 42.4 285 19 10 6.6 3.6 | 5.9 42.6 265 17 9 9.5 5.2 12000 7.0 44.6 285 18 9 9.1 5.0 | 7.0 44.6 265 15 8 7.3 4.0 11750 7.6 45.7 285 17 9 8.9 4.9 | 7.5 45.5 265 14 7 7.7 4.2 11500 8.2 46.8 285 16 8 7.5 4.1 | 8.1 46.6 265 13 6 8.7 4.8 11250 8.7 47.7 285 15 8 7.8 4.3 | 8.8 47.8 265 11 6 8.7 4.8 11000 9.3 48.7 285 15 8 9.0 4.9 | 9.3 48.7 270 9 5 8.3 4.6 10750 10.0 50.0 290 15 7 9.0 5.0 | 9.9 49.8 270 7 4 8.2 4.5 10500 10.6 51.1 290 14 7 7.8 4.3 | 10.5 50.9 275 5 3 9.0 5.0 10250 11.0 51.8 295 14 7 4.7 2.6 | 11.2 52.2 280 4 2 9.9 5.4 10000 11.3 52.3 300 14 7 3.7 2.0 | 11.9 53.4 300 3 1 9.6 5.2 9750 11.6 52.9 305 14 7 4.5 2.5 | 12.7 54.9 335 2 1 10.2 5.6 9500 11.8 53.2 310 14 7 2.5 1.4 | 13.4 56.1 015 2 1 8.1 4.4 9250 11.8 53.2 320 14 7 -0.2 -0.1 | 13.9 57.0 030 3 2 8.1 4.4 9000 11.8 53.2 325 15 8 1.0 0.5 | 14.6 58.3 030 3 2 11.1 6.1 8750 11.8 53.2 335 15 8 1.1 0.6 | 15.5 59.9 035 3 2 11.3 6.2 8500 11.8 53.2 340 16 8 3.6 2.0 | 16.3 61.3 035 4 2 10.8 6.0 8250 12.2 54.0 340 15 8 8.0 4.4 | 17.1 62.8 040 4 2 11.1 6.1 8000 12.9 55.2 335 14 7 9.1 5.0 | 18.1 64.6 040 4 2 18.6 10.2 7750 13.7 56.7 335 13 7 16.6 9.1 | 19.9 67.8 045 4 2 29.0 15.9 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 07/04/2024 at 1500 MDT | 07/04/2024 at 1800 MDT | CAPE... +244.2 LI... -3.3 | CAPE... +403.3 LI... -3.6 CINH... -3.2 K Index... +25.6 | CINH... -11.7 K Index... +28.3 | 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 -60.7 -77.3 280 39 20 2.1 1.1 | -61.2 -78.2 280 40 20 3.3 1.8 45000 -56.3 -69.3 280 55 28 4.7 2.6 | -55.5 -67.9 285 52 27 4.9 2.7 40000 -49.1 -56.4 280 62 32 5.1 2.8 | -48.1 -54.6 285 63 32 4.9 2.7 38000 -46.1 -51.0 275 61 31 5.1 2.8 | -44.8 -48.6 280 63 33 4.9 2.7 36000 -42.6 -44.7 270 60 31 5.2 2.9 | -41.9 -43.4 280 64 33 4.9 2.7 34000 -38.5 -37.3 270 60 31 7.1 3.9 | -38.4 -37.1 280 63 32 5.9 3.2 32000 -34.2 -29.6 270 60 31 7.1 3.9 | -34.9 -30.8 280 62 32 5.8 3.2 30000 -30.2 -22.4 275 59 30 6.5 3.6 | -30.8 -23.4 280 61 31 7.1 3.9 29000 -28.3 -18.9 275 58 30 6.6 3.6 | -28.7 -19.7 280 61 31 7.1 3.9 28000 -26.3 -15.3 275 57 29 6.8 3.7 | -26.6 -15.9 285 60 31 6.8 3.7 27000 -24.2 -11.6 275 57 29 7.0 3.9 | -24.6 -12.3 280 59 30 6.4 3.5 26000 -22.1 -7.8 275 56 29 7.0 3.9 | -22.7 -8.9 280 58 30 6.4 3.5 25000 -20.0 -4.0 280 56 29 7.2 3.9 | -20.8 -5.4 280 57 29 6.6 3.6 24000 -18.1 -0.6 280 55 28 5.8 3.2 | -19.3 -2.7 280 54 28 4.8 2.6 23000 -16.4 2.5 280 54 28 5.8 3.2 | -17.9 -0.2 280 50 26 4.8 2.7 22000 -14.3 6.3 285 52 27 5.2 2.9 | -16.1 3.0 275 45 23 6.4 3.5 21000 -12.9 8.8 280 46 23 4.9 2.7 | -13.9 7.0 275 41 21 7.5 4.1 20000 -11.5 11.3 275 39 20 5.3 2.9 | -11.8 10.8 275 37 19 7.7 4.2 19500 -10.8 12.6 270 36 19 5.9 3.2 | -10.7 12.7 270 35 18 7.9 4.3 19000 -9.7 14.5 270 34 18 9.0 5.0 | -9.4 15.1 270 33 17 9.1 5.0 18500 -8.4 16.9 270 33 17 8.8 4.8 | -8.1 17.4 275 32 17 9.0 4.9 18000 -7.1 19.2 270 32 16 9.0 4.9 | -6.8 19.8 275 31 16 8.9 4.9 17500 -5.8 21.6 270 30 16 9.0 4.9 | -5.6 21.9 275 29 15 9.0 4.9 17000 -4.5 23.9 270 29 15 8.8 4.9 | -4.3 24.3 275 26 14 8.8 4.8 16500 -3.3 26.1 270 26 13 8.0 4.4 | -3.1 26.4 275 23 12 8.0 4.4 16000 -2.1 28.2 270 23 12 8.1 4.5 | -2.0 28.4 275 20 10 8.1 4.5 15500 -1.0 30.2 265 19 10 7.5 4.1 | -0.8 30.6 275 16 8 7.7 4.2 15000 0.1 32.2 265 16 8 7.6 4.2 | 0.3 32.5 270 12 6 7.7 4.2 14500 1.1 34.0 260 12 6 7.5 4.1 | 1.4 34.5 265 8 4 7.8 4.3 14000 2.2 36.0 250 8 4 7.5 4.1 | 2.5 36.5 255 5 3 7.8 4.3 13500 3.3 37.9 225 5 2 7.4 4.1 | 3.7 38.7 220 3 2 7.7 4.2 13000 4.3 39.7 180 4 2 7.6 4.1 | 4.8 40.6 205 3 2 7.6 4.2 12500 5.6 42.1 160 5 3 9.9 5.4 | 6.0 42.8 185 3 2 8.8 4.8 12000 7.1 44.8 155 6 3 10.1 5.6 | 7.3 45.1 165 4 2 9.6 5.3 11750 7.8 46.0 150 6 3 9.7 5.3 | 8.0 46.4 155 4 2 9.0 4.9 11500 8.5 47.3 150 6 3 8.7 4.8 | 8.6 47.5 150 5 2 7.9 4.3 11250 9.2 48.6 150 7 3 9.4 5.2 | 9.2 48.6 145 5 3 9.1 5.0 11000 9.9 49.8 145 7 3 10.1 5.5 | 10.0 50.0 145 5 3 10.1 5.6 10750 10.7 51.3 145 7 4 10.1 5.6 | 10.7 51.3 145 6 3 10.1 5.5 10500 11.4 52.5 145 7 4 9.3 5.1 | 11.4 52.5 140 6 3 9.3 5.1 10250 12.1 53.8 140 7 4 9.3 5.1 | 12.1 53.8 140 6 3 9.2 5.0 10000 12.8 55.0 140 7 4 10.1 5.5 | 12.8 55.0 140 6 3 9.9 5.4 9750 13.5 56.3 140 8 4 10.2 5.6 | 13.6 56.5 140 7 3 10.0 5.5 9500 14.3 57.7 140 8 4 9.0 5.0 | 14.3 57.7 140 7 3 8.8 4.8 9250 14.9 58.8 140 8 4 9.1 5.0 | 14.9 58.8 140 7 4 8.9 4.9 9000 15.7 60.3 140 8 4 10.8 5.9 | 15.7 60.3 140 7 4 10.8 5.9 8750 16.5 61.7 135 8 4 10.9 6.0 | 16.5 61.7 140 7 4 11.1 6.1 8500 17.3 63.1 135 8 4 10.6 5.8 | 17.3 63.1 135 7 4 10.4 5.7 8250 18.1 64.6 135 9 4 11.1 6.1 | 18.0 64.4 135 7 4 9.8 5.4 8000 19.1 66.4 135 9 4 18.8 10.3 | 18.9 66.0 135 7 4 14.2 7.8 7750 20.9 69.6 130 8 4 29.0 15.9 | 20.2 68.4 130 7 4 20.6 11.3 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