Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
582 UXUS97 KPUB 251212 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0611 MDT Tuesday, June 25, 2024 This forecast is for the Air Force Academy for Tuesday, June 25, 2024: If the trigger temperature of 77.0 F/25.0 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1553 ft/min (7.9 m/s) Maximum height of thermals.................. 23478 ft MSL (15883 ft AGL) Forecast maximum temperature................... 91.0 F/33.2 C Time of trigger temperature.................... 0830 MDT Time of overdevelopment........................ 1500 MDT Middle/high clouds during soaring window....... None Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 20484 ft MSL (12889 ft AGL) Thermal soaring outlook for Wednesday 06/26.... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:35:19 / 20:28:56 MDT Total possible sunshine........... 14 hr 53 min 37 sec (893 min 37 sec) Altitude of sun at 13:02:07 MDT... 74.37 degrees Upper air data from numerical model forecast valid on 06/25/2024 at 0600 MDT Freezing level.................. 16811 ft MSL (9216 ft AGL) Convective condensation level... 20150 ft MSL (12555 ft AGL) Lifted condensation level....... 21702 ft MSL (14107 ft AGL) Lifted index.................... -1.6 K index......................... +10.2 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 -64.4 -83.9 290 40 20 4.1 2.3 M M M M M 45000 -56.4 -69.5 285 53 27 6.5 3.6 M M M M M 40000 -46.8 -52.2 285 59 30 6.3 3.5 M M M M M 38000 -43.0 -45.4 285 58 30 6.3 3.5 M M M M M 36000 -39.3 -38.7 285 58 30 6.2 3.4 M M M M M 34000 -35.9 -32.6 285 53 27 5.6 3.1 M M M M M 32000 -32.1 -25.8 285 47 24 5.9 3.3 M M M M M 30000 -28.1 -18.6 285 41 21 6.7 3.7 40.4 104.7 6.0 M M 29000 -26.1 -15.0 285 38 20 6.7 3.7 39.3 102.7 5.2 M M 28000 -24.1 -11.4 285 35 18 7.0 3.8 38.3 100.9 4.4 M M 27000 -22.0 -7.6 285 30 15 7.0 3.9 37.1 98.8 3.5 M M 26000 -19.9 -3.8 285 24 12 7.1 3.9 36.1 97.0 2.7 M M 25000 -17.8 -0.0 280 19 10 6.7 3.7 35.3 95.5 2.0 M M 24000 -16.1 3.0 285 17 9 5.7 3.1 33.8 92.8 0.7 M M 23000 -14.5 5.9 285 15 8 5.8 3.2 32.3 90.2 -0.5 1520 7.7 22000 -12.8 9.0 290 14 7 6.5 3.6 31.1 87.9 -1.7 1441 7.3 21000 -10.6 12.9 300 14 7 7.5 4.1 30.2 86.4 -2.5 1345 6.8 20000 -8.4 16.9 305 16 8 7.5 4.1 29.5 85.0 -3.3 1249 6.3 19500 -7.3 18.9 310 16 8 7.4 4.1 29.1 84.4 -3.6 1201 6.1 19000 -5.4 22.3 315 17 9 8.5 4.7 28.7 83.7 -3.9 1124 5.7 18500 -4.2 24.4 315 18 9 8.5 4.7 28.5 83.4 -4.1 1070 5.4 18000 -2.9 26.8 320 18 9 8.6 4.7 28.3 83.0 -4.3 1017 5.2 17500 -1.6 29.1 320 18 9 8.6 4.7 28.2 82.7 -4.5 963 4.9 17000 -0.3 31.5 325 18 9 8.4 4.6 28.0 82.4 -4.7 910 4.6 16500 0.9 33.6 325 17 9 8.1 4.4 27.7 81.9 -5.0 859 4.4 16000 2.1 35.8 330 16 8 8.1 4.4 27.4 81.4 -5.3 809 4.1 15500 3.3 37.9 335 15 8 8.6 4.7 27.2 81.0 -5.5 757 3.8 15000 4.6 40.3 335 15 8 8.6 4.7 27.0 80.7 -5.8 704 3.6 14500 5.9 42.6 335 14 7 8.5 4.7 26.9 80.3 -6.0 652 3.3 14000 7.1 44.8 335 13 7 8.5 4.7 26.6 80.0 -6.2 600 3.0 13500 8.4 47.1 335 13 7 8.7 4.8 26.5 79.6 -6.5 548 2.8 13000 9.6 49.3 335 12 6 8.6 4.7 26.3 79.4 -6.7 494 2.5 12500 10.8 51.4 335 12 6 8.2 4.5 26.1 79.0 -7.0 444 2.3 12000 12.0 53.6 335 12 6 7.7 4.3 25.8 78.5 -7.3 393 2.0 11750 12.6 54.7 335 12 6 8.9 4.9 25.7 78.2 -7.4 368 1.9 11500 13.3 55.9 335 12 6 10.3 5.7 25.7 78.3 -7.5 339 1.7 11250 14.1 57.4 335 13 7 9.1 5.0 25.7 78.3 -7.5 310 1.6 11000 14.7 58.5 335 13 7 8.5 4.7 25.6 78.1 -7.6 284 1.4 10750 15.3 59.5 335 13 7 7.9 4.3 25.5 77.9 -7.7 258 1.3 10500 15.9 60.6 335 14 7 10.9 6.0 25.4 77.7 -7.8 232 1.2 10250 16.9 62.4 335 14 7 11.3 6.2 25.6 78.1 -7.7 197 1.0 10000 17.5 63.5 335 14 7 8.5 4.6 25.6 78.0 -7.8 170 0.9 9750 18.2 64.8 335 14 7 9.5 5.2 25.5 77.9 -7.8 142 0.7 9500 18.9 66.0 335 14 7 8.2 4.5 25.5 77.9 -7.9 115 0.6 9250 19.4 66.9 335 14 7 6.7 3.7 25.3 77.5 -8.1 91 0.5 9000 19.9 67.8 335 14 7 7.1 3.9 25.1 77.1 -8.4 69 0.4 8750 20.4 68.7 335 14 7 7.7 4.2 24.9 76.8 -8.6 47 0.2 8500 20.9 69.6 335 14 7 6.7 3.7 24.7 76.5 -8.9 24 0.1 8250 21.2 70.2 335 14 7 -1.0 -0.5 24.3 75.7 -9.4 9 0.0 8000 20.4 68.7 325 13 7 -21.5 -11.8 22.8 73.0 -10.9 25 0.1 7750 17.8 64.0 310 10 5 -41.5 -22.7 19.6 67.2 -14.2 95 0.5 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 * * * * * * 06/25/2024 at 0900 MDT | 06/25/2024 at 1200 MDT | CAPE... +13.3 LI... +0.8 | CAPE... +72.0 LI... -0.8 CINH... -6.0 K Index... +14.7 | CINH... -1.3 K Index... +15.4 | 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 -63.5 -82.3 290 33 17 3.0 1.6 | -63.1 -81.6 285 30 16 3.2 1.8 45000 -56.8 -70.2 285 51 26 6.3 3.5 | -56.6 -69.9 290 48 25 6.0 3.3 40000 -47.3 -53.1 290 59 30 6.5 3.6 | -47.4 -53.3 290 60 31 6.8 3.7 38000 -43.4 -46.1 290 57 29 6.5 3.6 | -43.3 -45.9 290 58 30 6.8 3.7 36000 -39.4 -38.9 290 55 28 6.3 3.5 | -39.3 -38.7 290 57 29 6.5 3.5 34000 -35.7 -32.3 290 50 26 5.4 3.0 | -35.7 -32.3 290 50 26 5.2 2.9 32000 -32.5 -26.5 295 45 23 6.1 3.3 | -32.6 -26.7 290 43 22 5.9 3.2 30000 -28.2 -18.8 295 41 21 7.2 3.9 | -28.5 -19.3 295 40 21 7.0 3.8 29000 -26.1 -15.0 295 38 20 7.2 3.9 | -26.4 -15.5 295 39 20 7.0 3.8 28000 -24.0 -11.2 295 36 18 6.8 3.7 | -24.3 -11.7 295 38 19 7.4 4.0 27000 -21.9 -7.4 295 32 16 6.8 3.7 | -22.0 -7.6 295 36 18 7.3 4.0 26000 -19.9 -3.8 295 28 14 6.8 3.7 | -19.8 -3.6 295 34 17 7.4 4.0 25000 -17.9 -0.2 290 24 12 6.5 3.6 | -17.6 0.3 295 31 16 6.4 3.5 24000 -16.1 3.0 290 21 11 5.9 3.2 | -16.1 3.0 290 28 14 4.9 2.7 23000 -14.4 6.1 290 19 10 5.9 3.2 | -14.7 5.5 285 25 13 5.0 2.8 22000 -12.6 9.3 290 16 8 6.3 3.5 | -13.2 8.2 275 22 12 5.8 3.2 21000 -10.6 12.9 300 16 8 6.9 3.8 | -11.2 11.8 285 20 10 6.7 3.7 20000 -8.1 17.4 315 18 9 7.0 3.8 | -8.8 16.2 305 18 10 6.7 3.7 19500 -7.1 19.2 320 18 9 7.5 4.1 | -7.7 18.1 310 18 9 7.9 4.4 19000 -5.9 21.4 315 18 9 8.0 4.4 | -6.5 20.3 315 19 10 8.8 4.8 18500 -4.8 23.4 315 18 9 8.0 4.4 | -5.2 22.6 320 20 10 8.8 4.8 18000 -3.6 25.5 315 18 9 9.0 5.0 | -3.9 25.0 325 20 10 9.1 5.0 17500 -2.3 27.9 315 17 9 9.0 4.9 | -2.5 27.5 325 20 10 9.1 5.0 17000 -1.0 30.2 320 17 9 9.1 5.0 | -1.2 29.8 325 20 10 9.2 5.1 16500 0.4 32.7 320 16 8 9.1 5.0 | 0.1 32.2 330 20 10 9.3 5.1 16000 1.7 35.1 320 15 8 9.1 5.0 | 1.4 34.5 330 19 10 9.4 5.1 15500 3.0 37.4 320 14 7 8.4 4.6 | 2.8 37.0 330 18 9 9.7 5.3 15000 4.3 39.7 320 14 7 8.5 4.6 | 4.2 39.6 330 16 8 9.8 5.4 14500 5.6 42.1 320 13 7 8.6 4.7 | 5.6 42.1 335 14 7 9.7 5.3 14000 6.9 44.4 325 12 6 8.6 4.7 | 7.0 44.6 335 13 7 9.7 5.3 13500 8.1 46.6 325 11 6 8.6 4.7 | 8.5 47.3 340 12 6 9.4 5.2 13000 9.4 48.9 330 11 5 8.8 4.8 | 9.8 49.6 340 11 6 9.8 5.4 12500 10.7 51.3 335 10 5 9.2 5.1 | 11.4 52.5 340 11 6 10.4 5.7 12000 12.2 54.0 340 10 5 10.1 5.6 | 12.9 55.2 345 11 5 10.5 5.8 11750 12.9 55.2 340 10 5 8.6 4.7 | 13.7 56.7 345 10 5 9.6 5.3 11500 13.5 56.3 345 10 5 7.0 3.9 | 14.4 57.9 345 10 5 9.1 5.0 11250 14.0 57.2 345 10 5 8.2 4.5 | 15.1 59.2 345 10 5 9.9 5.5 11000 14.7 58.5 345 10 5 8.7 4.8 | 15.9 60.6 345 10 5 10.0 5.5 10750 15.3 59.5 350 10 5 8.7 4.8 | 16.6 61.9 345 10 5 10.0 5.5 10500 16.0 60.8 350 10 5 8.3 4.5 | 17.4 63.3 345 10 5 9.9 5.5 10250 16.5 61.7 350 11 5 8.6 4.7 | 18.1 64.6 350 10 5 9.8 5.4 10000 17.2 63.0 350 11 6 9.1 5.0 | 18.8 65.8 350 10 5 9.6 5.3 9750 17.9 64.2 350 11 6 9.6 5.3 | 19.5 67.1 350 10 5 10.2 5.6 9500 18.5 65.3 350 12 6 7.1 3.9 | 20.3 68.5 350 9 5 8.0 4.4 9250 19.0 66.2 350 12 6 8.0 4.4 | 20.8 69.4 350 9 5 9.0 4.9 9000 19.8 67.6 345 12 6 11.6 6.4 | 21.6 70.9 350 9 5 11.9 6.5 8750 20.6 69.1 345 12 6 11.3 6.2 | 22.5 72.5 350 9 5 11.4 6.3 8500 21.4 70.5 345 11 6 10.7 5.9 | 23.4 74.1 355 9 5 10.7 5.9 8250 22.1 71.8 340 11 6 9.8 5.4 | 24.1 75.4 355 9 5 11.0 6.0 8000 22.9 73.2 340 10 5 13.8 7.6 | 25.2 77.4 355 9 4 18.5 10.1 7750 24.1 75.4 340 9 5 19.6 10.7 | 26.8 80.2 355 8 4 27.4 15.0 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 06/25/2024 at 1500 MDT | 06/25/2024 at 1800 MDT | CAPE... +84.7 LI... -0.2 | CAPE... +84.0 LI... +0.1 CINH... -8.7 K Index... +24.8 | CINH... -28.8 K Index... +27.5 | 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 -63.1 -81.6 285 28 14 4.1 2.2 | -63.3 -81.9 285 23 12 4.5 2.5 45000 -56.2 -69.2 290 42 22 5.5 3.0 | -55.9 -68.6 295 34 18 5.5 3.0 40000 -47.5 -53.5 295 58 30 6.9 3.8 | -47.3 -53.1 300 53 27 7.1 3.9 38000 -43.4 -46.1 295 59 30 6.9 3.8 | -42.5 -44.5 295 56 29 7.1 3.9 36000 -38.8 -37.8 295 60 31 6.0 3.3 | -38.3 -36.9 295 59 31 6.0 3.3 34000 -35.2 -31.4 295 54 28 5.9 3.2 | -34.7 -30.5 295 57 29 5.8 3.2 32000 -31.7 -25.1 295 48 25 5.8 3.2 | -31.2 -24.2 300 55 28 5.9 3.2 30000 -28.4 -19.1 290 43 22 5.5 3.0 | -27.8 -18.0 295 49 25 5.8 3.2 29000 -26.8 -16.2 290 42 21 5.6 3.1 | -26.0 -14.8 290 46 23 5.9 3.2 28000 -24.9 -12.8 290 40 20 8.2 4.5 | -24.3 -11.7 290 43 22 6.1 3.4 27000 -22.6 -8.7 290 38 20 7.9 4.3 | -22.5 -8.5 290 41 21 6.2 3.4 26000 -20.2 -4.4 295 37 19 7.9 4.3 | -20.7 -5.3 295 39 20 6.2 3.4 25000 -17.9 -0.2 295 35 18 6.7 3.7 | -18.9 -2.0 295 37 19 6.7 3.7 24000 -16.4 2.5 295 32 17 4.9 2.7 | -16.7 1.9 290 33 17 7.4 4.1 23000 -15.0 5.0 290 29 15 5.0 2.7 | -14.0 6.8 285 28 15 7.5 4.1 22000 -13.5 7.7 290 26 14 6.9 3.8 | -11.9 10.6 280 24 12 7.8 4.3 21000 -10.4 13.3 285 23 12 8.7 4.8 | -9.6 14.7 275 17 9 7.8 4.3 20000 -8.0 17.6 285 21 11 8.8 4.8 | -7.4 18.7 265 10 5 7.8 4.3 19500 -6.8 19.8 285 19 10 7.9 4.4 | -6.3 20.7 255 7 4 6.7 3.7 19000 -5.7 21.7 285 16 8 7.4 4.1 | -5.4 22.3 250 6 3 5.9 3.2 18500 -4.6 23.7 290 12 6 7.3 4.0 | -4.5 23.9 250 4 2 5.5 3.0 18000 -3.3 26.1 300 10 5 9.4 5.1 | -3.5 25.7 250 3 2 9.0 4.9 17500 -2.0 28.4 305 8 4 9.2 5.0 | -2.2 28.0 255 2 1 8.7 4.8 17000 -0.6 30.9 320 7 3 9.6 5.3 | -0.9 30.4 265 1 0 9.0 4.9 16500 0.9 33.6 325 6 3 9.9 5.4 | 0.5 32.9 000 0 0 9.3 5.1 16000 2.4 36.3 335 6 3 9.8 5.4 | 1.9 35.4 035 1 1 9.3 5.1 15500 3.8 38.8 340 6 3 9.3 5.1 | 3.3 37.9 040 2 1 9.9 5.4 15000 5.2 41.4 350 6 3 9.3 5.1 | 4.8 40.6 040 2 1 9.9 5.4 14500 6.6 43.9 355 6 3 9.8 5.4 | 6.2 43.2 040 3 1 9.7 5.3 14000 8.1 46.6 355 7 3 9.8 5.4 | 7.7 45.9 030 3 2 9.6 5.3 13500 9.5 49.1 360 7 4 9.7 5.3 | 9.1 48.4 030 4 2 9.5 5.2 13000 11.0 51.8 360 7 4 9.9 5.4 | 10.5 50.9 020 4 2 9.3 5.1 12500 12.5 54.5 005 7 4 10.3 5.7 | 11.9 53.4 020 5 2 9.6 5.3 12000 14.1 57.4 005 7 4 10.8 5.9 | 13.4 56.1 015 5 3 10.4 5.7 11750 14.8 58.6 005 7 4 9.2 5.1 | 14.2 57.6 015 6 3 9.4 5.1 11500 15.5 59.9 005 7 4 8.5 4.7 | 14.8 58.6 015 6 3 8.6 4.7 11250 16.2 61.2 005 8 4 10.2 5.6 | 15.5 59.9 010 6 3 9.8 5.4 11000 16.9 62.4 005 8 4 10.3 5.7 | 16.2 61.2 010 6 3 9.9 5.4 10750 17.7 63.9 005 8 4 10.7 5.8 | 17.0 62.6 010 7 3 10.4 5.7 10500 18.5 65.3 005 8 4 9.1 5.0 | 17.7 63.9 005 7 4 8.3 4.5 10250 19.1 66.4 005 8 4 9.0 5.0 | 18.3 64.9 005 7 4 8.1 4.4 10000 19.9 67.8 010 8 4 10.2 5.6 | 19.0 66.2 005 8 4 10.0 5.5 9750 20.6 69.1 010 8 4 10.6 5.8 | 19.7 67.5 005 8 4 9.8 5.4 9500 21.4 70.5 010 8 4 7.9 4.3 | 20.4 68.7 360 9 4 8.6 4.7 9250 21.9 71.4 010 8 4 8.4 4.6 | 21.0 69.8 360 9 5 8.7 4.8 9000 22.7 72.9 010 8 4 11.6 6.4 | 21.8 71.2 360 9 5 10.4 5.7 8750 23.5 74.3 010 8 4 10.9 6.0 | 22.5 72.5 360 9 5 10.1 5.5 8500 24.4 75.9 010 8 4 10.5 5.8 | 23.3 73.9 360 10 5 10.2 5.6 8250 25.1 77.2 010 8 4 10.8 5.9 | 24.0 75.2 360 10 5 10.2 5.6 8000 26.1 79.0 010 8 4 17.2 9.4 | 24.8 76.6 360 9 5 9.7 5.3 7750 27.7 81.9 010 8 4 24.8 13.6 | 25.4 77.7 355 8 4 9.2 5.0 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