Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
425 UXUS97 KPUB 011203 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0603 MDT Monday, July 1, 2024 This forecast is for the Air Force Academy for Monday, July 1, 2024: If the trigger temperature of 73.7 F/23.2 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 762 ft/min (3.9 m/s) Maximum height of thermals.................. 18004 ft MSL (10367 ft AGL) Forecast maximum temperature................... 83.0 F/28.8 C Time of trigger temperature.................... 0900 MDT Time of overdevelopment........................ None 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................. 14374 ft MSL (6737 ft AGL) Thermal soaring outlook for Tuesday 07/02...... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:37:52 / 20:28:47 MDT Total possible sunshine........... 14 hr 50 min 55 sec (890 min 55 sec) Altitude of sun at 13:03:20 MDT... 74.03 degrees Upper air data from numerical model forecast valid on 07/01/2024 at 0600 MDT Freezing level.................. 16708 ft MSL (9071 ft AGL) Convective condensation level... 14153 ft MSL (6516 ft AGL) Lifted condensation level....... 15560 ft MSL (7922 ft AGL) Lifted index.................... -4.3 K index......................... +29.0 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 -64.7 -84.5 250 29 15 2.2 1.2 M M M M M 45000 -58.5 -73.3 240 42 21 6.5 3.5 M M M M M 40000 -48.5 -55.3 230 51 26 7.5 4.1 M M M M M 38000 -44.0 -47.2 230 48 25 7.5 4.1 M M M M M 36000 -39.5 -39.1 235 46 24 7.8 4.3 M M M M M 34000 -34.1 -29.4 235 45 23 8.1 4.4 M M M M M 32000 -29.3 -20.7 235 44 22 8.3 4.6 46.4 115.5 13.7 M M 30000 -25.1 -13.2 230 40 21 7.1 3.9 44.1 111.3 12.2 M M 29000 -23.0 -9.4 225 39 20 7.1 3.9 43.1 109.7 11.6 M M 28000 -21.0 -5.8 220 38 20 6.3 3.5 42.1 107.9 10.9 M M 27000 -19.1 -2.4 220 39 20 6.4 3.5 40.8 105.4 9.9 M M 26000 -17.2 1.0 220 40 20 6.4 3.5 39.6 103.3 9.0 M M 25000 -15.3 4.5 215 40 21 6.3 3.5 38.5 101.3 8.1 M M 24000 -13.5 7.7 215 39 20 6.1 3.4 37.1 98.8 7.0 M M 23000 -11.7 10.9 210 37 19 6.1 3.4 35.8 96.5 6.0 M M 22000 -9.9 14.2 210 35 18 5.9 3.2 34.7 94.4 5.0 M M 21000 -7.9 17.8 210 31 16 5.5 3.0 32.7 90.9 3.3 M M 20000 -6.4 20.5 205 27 14 5.5 3.0 31.3 88.3 2.1 M M 19500 -5.6 21.9 205 25 13 6.0 3.3 30.6 87.1 1.5 M M 19000 -4.6 23.7 205 24 13 6.9 3.8 30.1 86.1 0.9 M M 18500 -3.7 25.3 205 24 12 6.9 3.8 29.6 85.3 0.4 M M 18000 -2.7 27.1 205 23 12 7.6 4.2 29.2 84.5 -0.1 957 4.9 17500 -1.6 29.1 205 22 12 7.6 4.2 28.8 83.8 -0.4 910 4.6 17000 -0.5 31.1 210 22 11 7.5 4.1 28.5 83.2 -0.8 863 4.4 16500 0.5 32.9 210 22 11 7.2 4.0 28.1 82.5 -1.2 817 4.1 16000 1.5 34.7 210 21 11 7.2 4.0 27.6 81.8 -1.7 771 3.9 15500 2.6 36.7 215 21 11 7.2 3.9 27.2 81.0 -2.1 725 3.7 15000 3.6 38.5 215 21 11 7.2 3.9 26.8 80.3 -2.5 679 3.4 14500 4.7 40.5 220 21 11 7.5 4.1 26.4 79.6 -2.9 632 3.2 14000 5.8 42.4 220 21 11 7.7 4.2 26.1 78.9 -3.3 584 3.0 13500 6.9 44.4 225 22 11 8.1 4.4 25.8 78.4 -3.6 537 2.7 13000 8.1 46.6 225 22 11 8.4 4.6 25.6 78.1 -3.9 484 2.5 12500 9.2 48.6 230 22 11 7.2 4.0 25.2 77.4 -4.3 438 2.2 12000 10.3 50.5 230 23 12 8.4 4.6 24.9 76.9 -4.6 390 2.0 11750 10.9 51.6 230 23 12 7.8 4.3 24.8 76.7 -4.8 365 1.9 11500 11.4 52.5 230 23 12 6.4 3.5 24.6 76.3 -5.0 342 1.7 11250 11.8 53.2 230 24 12 6.3 3.4 24.3 75.8 -5.3 322 1.6 11000 12.3 54.1 230 24 12 6.5 3.6 24.1 75.3 -5.6 301 1.5 10750 12.7 54.9 235 25 13 7.0 3.9 23.8 74.9 -5.9 280 1.4 10500 13.2 55.8 235 25 13 4.8 2.6 23.6 74.5 -6.2 260 1.3 10250 13.4 56.1 235 26 14 3.5 1.9 23.1 73.6 -6.7 245 1.2 10000 13.7 56.7 235 26 14 4.9 2.7 22.7 72.8 -7.2 229 1.2 9750 14.0 57.2 235 27 14 4.6 2.5 22.3 72.1 -7.6 212 1.1 9500 14.3 57.7 235 27 14 4.6 2.5 21.9 71.5 -8.0 196 1.0 9250 14.7 58.5 240 27 14 5.4 3.0 21.6 70.8 -8.4 178 0.9 9000 15.1 59.2 240 27 14 6.2 3.4 21.3 70.3 -8.8 158 0.8 8750 15.5 59.9 240 27 14 6.2 3.4 21.0 69.8 -9.1 139 0.7 8500 15.9 60.6 245 26 14 5.9 3.3 20.7 69.3 -9.5 120 0.6 8250 16.3 61.3 240 23 12 -1.3 -0.7 19.8 67.6 -10.5 91 0.5 8000 16.0 60.8 240 16 8 -6.8 -3.8 18.7 65.7 -11.6 95 0.5 7750 15.6 60.1 235 10 5 2.1 1.2 17.7 63.8 -12.8 99 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 * * * * * * 07/01/2024 at 0900 MDT | 07/01/2024 at 1200 MDT | CAPE... +13.5 LI... -0.4 | CAPE... +367.0 LI... -1.9 CINH... -47.3 K Index... +28.3 | CINH... -2.9 K Index... +24.5 | 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 -64.8 -84.6 230 33 17 2.1 1.1 | -64.8 -84.6 230 38 20 2.4 1.3 45000 -58.9 -74.0 230 45 23 6.5 3.6 | -58.4 -73.1 230 48 25 6.5 3.6 40000 -48.7 -55.7 225 49 25 7.9 4.3 | -48.4 -55.1 230 50 26 7.6 4.2 38000 -44.0 -47.2 220 47 24 7.9 4.3 | -43.8 -46.8 230 50 26 7.6 4.2 36000 -39.2 -38.6 220 46 24 7.5 4.1 | -39.2 -38.6 230 51 26 7.4 4.1 34000 -34.5 -30.1 220 41 21 7.0 3.9 | -34.9 -30.8 230 49 25 7.2 4.0 32000 -30.3 -22.5 225 37 19 8.2 4.5 | -30.1 -22.2 230 48 25 8.2 4.5 30000 -25.7 -14.3 230 37 19 7.8 4.3 | -25.9 -14.6 230 44 23 7.1 3.9 29000 -23.4 -10.1 235 38 19 7.9 4.3 | -23.8 -10.8 230 43 22 7.2 3.9 28000 -21.1 -6.0 240 38 20 6.7 3.7 | -21.7 -7.1 230 41 21 6.8 3.7 27000 -19.1 -2.4 245 40 20 6.8 3.7 | -19.7 -3.5 230 40 21 6.8 3.8 26000 -17.1 1.2 250 41 21 6.8 3.7 | -17.7 0.1 230 39 20 6.9 3.8 25000 -15.1 4.8 255 43 22 6.8 3.8 | -15.7 3.7 230 38 19 6.8 3.7 24000 -13.1 8.4 250 42 21 6.9 3.8 | -13.7 7.3 230 36 18 6.7 3.7 23000 -11.1 12.0 250 40 21 6.9 3.8 | -11.8 10.8 235 34 18 6.7 3.7 22000 -9.1 15.6 245 39 20 6.6 3.6 | -9.9 14.2 235 32 17 6.6 3.6 21000 -7.0 19.4 240 37 19 5.9 3.2 | -8.0 17.6 240 30 15 6.3 3.5 20000 -5.3 22.5 230 37 19 6.0 3.3 | -6.1 21.0 240 27 14 6.3 3.5 19500 -4.5 23.9 225 37 19 6.1 3.3 | -4.8 23.4 245 26 13 6.5 3.6 19000 -3.6 25.5 225 37 19 6.3 3.4 | -3.8 25.2 245 26 13 6.8 3.8 18500 -2.7 27.1 220 37 19 6.2 3.4 | -2.8 27.0 245 26 13 6.8 3.7 18000 -1.7 28.9 215 37 19 6.9 3.8 | -1.7 28.9 250 26 13 7.1 3.9 17500 -0.7 30.7 215 36 19 7.0 3.8 | -0.7 30.7 255 24 12 7.1 3.9 17000 0.3 32.5 215 35 18 6.9 3.8 | 0.4 32.7 260 23 12 6.7 3.7 16500 1.3 34.3 220 34 18 6.6 3.6 | 1.2 34.2 270 22 11 5.7 3.1 16000 2.2 36.0 220 33 17 6.7 3.7 | 2.0 35.6 275 21 11 5.6 3.1 15500 3.1 37.6 220 32 17 6.1 3.3 | 2.9 37.2 280 21 11 6.6 3.6 15000 4.0 39.2 225 31 16 6.1 3.3 | 3.9 39.0 290 22 11 6.5 3.6 14500 4.9 40.8 230 30 16 6.6 3.6 | 4.9 40.8 295 22 12 7.3 4.0 14000 5.9 42.6 230 29 15 6.9 3.8 | 6.0 42.8 300 22 11 7.7 4.2 13500 6.9 44.4 230 28 15 6.9 3.8 | 7.2 45.0 300 21 11 7.6 4.2 13000 7.8 46.0 225 26 13 6.7 3.7 | 8.2 46.8 305 20 10 7.8 4.3 12500 8.8 47.8 225 25 13 6.6 3.6 | 9.3 48.7 305 19 10 8.3 4.6 12000 9.7 49.5 220 23 12 6.2 3.4 | 10.5 50.9 300 16 8 8.5 4.7 11750 10.2 50.4 220 22 11 6.4 3.5 | 11.1 52.0 295 15 8 9.5 5.2 11500 10.6 51.1 220 21 11 6.8 3.8 | 11.8 53.2 290 14 7 10.9 6.0 11250 11.1 52.0 220 20 11 6.4 3.5 | 12.5 54.5 285 13 7 9.3 5.1 11000 11.6 52.9 220 20 10 6.0 3.3 | 13.1 55.6 285 13 6 8.4 4.6 10750 12.1 53.8 225 19 10 5.7 3.1 | 13.7 56.7 285 12 6 7.8 4.3 10500 12.5 54.5 230 18 9 7.1 3.9 | 14.4 57.9 280 12 6 11.3 6.2 10250 13.0 55.4 230 18 9 5.2 2.8 | 15.3 59.5 280 12 6 12.4 6.8 10000 13.2 55.8 240 18 9 2.3 1.3 | 16.1 61.0 280 11 6 9.5 5.2 9750 13.4 56.1 245 18 9 3.2 1.7 | 16.8 62.2 280 11 6 10.7 5.9 9500 13.7 56.7 250 18 9 2.5 1.4 | 17.6 63.7 280 11 6 8.8 4.8 9250 13.8 56.8 260 19 10 2.0 1.1 | 18.2 64.8 280 11 5 8.7 4.8 9000 13.9 57.0 265 19 10 3.6 2.0 | 18.9 66.0 280 10 5 10.7 5.9 8750 14.2 57.6 265 19 10 4.6 2.5 | 19.7 67.5 280 10 5 10.6 5.8 8500 14.4 57.9 270 19 10 4.6 2.5 | 20.5 68.9 280 10 5 10.5 5.7 8250 14.8 58.6 275 19 10 8.9 4.9 | 21.3 70.3 280 10 5 11.7 6.4 8000 15.7 60.3 275 17 9 14.8 8.1 | 22.3 72.1 275 9 5 17.8 9.8 7750 17.9 64.2 270 11 6 16.0 8.8 | 23.9 75.0 275 8 4 24.5 13.4 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 07/01/2024 at 1500 MDT | 07/01/2024 at 1800 MDT | CAPE... +270.8 LI... -2.5 | CAPE... +745.5 LI... -3.6 CINH... -1.6 K Index... +29.6 | CINH... -7.7 K Index... +26.3 | 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 -64.3 -83.7 240 43 22 1.6 0.9 | -64.3 -83.7 245 41 21 1.6 0.9 45000 -58.9 -74.0 235 53 27 6.3 3.5 | -59.5 -75.1 240 52 27 6.0 3.3 40000 -49.0 -56.2 225 57 29 7.9 4.3 | -49.3 -56.7 225 58 30 8.2 4.5 38000 -44.3 -47.7 225 59 30 7.9 4.3 | -44.4 -47.9 225 57 29 8.3 4.5 36000 -39.6 -39.3 220 61 32 8.0 4.4 | -39.4 -38.9 225 57 29 8.1 4.5 34000 -34.8 -30.6 225 59 30 8.1 4.4 | -34.5 -30.1 230 56 29 8.1 4.4 32000 -29.3 -20.7 235 56 29 8.4 4.6 | -29.7 -21.5 235 56 29 9.1 5.0 30000 -25.2 -13.4 235 49 25 7.0 3.8 | -25.4 -13.7 240 51 26 7.1 3.9 29000 -23.2 -9.8 240 46 24 7.0 3.9 | -23.3 -9.9 240 48 25 7.1 3.9 28000 -21.2 -6.2 240 43 22 6.5 3.6 | -21.2 -6.2 240 46 23 7.0 3.9 27000 -19.2 -2.6 245 39 20 6.6 3.6 | -19.0 -2.2 245 45 23 7.0 3.9 26000 -17.3 0.9 245 36 19 6.6 3.6 | -16.9 1.6 245 44 23 7.0 3.9 25000 -15.4 4.3 245 33 17 6.5 3.6 | -14.2 6.4 250 44 22 6.2 3.4 24000 -13.6 7.5 250 31 16 6.0 3.3 | -12.5 9.5 255 40 21 5.7 3.1 23000 -11.8 10.8 250 28 15 6.1 3.3 | -10.7 12.7 260 38 19 5.7 3.1 22000 -10.1 13.8 255 26 14 5.9 3.2 | -9.0 15.8 265 35 18 5.1 2.8 21000 -8.5 16.7 260 25 13 5.3 2.9 | -7.7 18.1 265 35 18 4.9 2.7 20000 -7.0 19.4 265 24 13 5.3 2.9 | -6.3 20.7 270 34 18 5.5 3.0 19500 -5.9 21.4 265 24 12 5.1 2.8 | -5.6 21.9 270 34 17 6.3 3.4 19000 -5.2 22.6 265 22 12 4.7 2.6 | -4.7 23.5 275 33 17 7.3 4.0 18500 -4.5 23.9 265 21 11 4.6 2.5 | -3.7 25.3 275 33 17 7.2 4.0 18000 -3.7 25.3 265 20 10 6.5 3.6 | -2.7 27.1 275 32 17 6.5 3.6 17500 -2.8 27.0 270 20 10 6.8 3.7 | -1.8 28.8 275 30 16 6.1 3.3 17000 -1.8 28.8 270 20 10 7.0 3.9 | -0.9 30.4 280 29 15 6.1 3.3 16500 -0.7 30.7 270 19 10 7.7 4.2 | -0.1 31.8 280 25 13 6.5 3.5 16000 0.5 32.9 275 18 9 7.6 4.2 | 0.9 33.6 280 21 11 6.4 3.5 15500 1.7 35.1 275 18 9 8.7 4.8 | 1.8 35.2 280 17 9 7.5 4.1 15000 3.0 37.4 275 17 9 8.7 4.8 | 2.9 37.2 280 15 8 7.8 4.3 14500 4.2 39.6 275 16 8 8.7 4.8 | 3.9 39.0 275 13 6 8.4 4.6 14000 5.5 41.9 275 16 8 8.8 4.8 | 5.2 41.4 275 12 6 9.0 5.0 13500 6.7 44.1 280 15 8 9.3 5.1 | 6.5 43.7 275 12 6 9.3 5.1 13000 8.0 46.4 275 14 7 9.8 5.4 | 8.1 46.6 275 12 6 10.7 5.9 12500 9.4 48.9 275 13 7 9.3 5.1 | 9.5 49.1 275 12 6 8.9 4.9 12000 10.8 51.4 275 13 7 8.8 4.8 | 10.8 51.4 275 11 6 8.8 4.8 11750 11.4 52.5 275 12 6 9.7 5.3 | 11.5 52.7 270 11 6 9.3 5.1 11500 12.2 54.0 270 12 6 11.0 6.0 | 12.2 54.0 270 11 6 10.6 5.8 11250 13.0 55.4 270 12 6 9.3 5.1 | 13.0 55.4 270 11 6 9.5 5.2 11000 13.6 56.5 270 12 6 8.3 4.6 | 13.6 56.5 270 11 6 8.5 4.6 10750 14.2 57.6 270 11 6 7.7 4.2 | 14.2 57.6 265 11 6 7.9 4.3 10500 14.8 58.6 270 11 6 11.1 6.1 | 14.9 58.8 265 11 5 10.7 5.9 10250 15.8 60.4 270 11 5 12.2 6.7 | 15.8 60.4 260 10 5 11.4 6.3 10000 16.5 61.7 265 10 5 9.4 5.2 | 16.4 61.5 260 10 5 8.3 4.6 9750 17.3 63.1 265 10 5 10.8 6.0 | 17.0 62.6 255 11 5 8.5 4.7 9500 18.0 64.4 265 9 5 7.9 4.4 | 17.6 63.7 250 11 6 8.0 4.4 9250 18.5 65.3 260 9 5 7.9 4.3 | 18.2 64.8 245 11 6 9.8 5.4 9000 19.3 66.7 260 9 4 11.2 6.1 | 19.0 66.2 240 11 6 10.1 5.5 8750 20.1 68.2 255 8 4 11.1 6.1 | 19.6 67.3 235 11 6 8.6 4.7 8500 20.9 69.6 255 8 4 10.9 6.0 | 20.3 68.5 230 11 6 8.7 4.8 8250 21.7 71.1 255 8 4 11.5 6.3 | 21.7 71.1 220 10 5 13.8 7.6 8000 22.7 72.9 250 7 4 17.5 9.6 | 22.8 73.0 215 9 5 17.0 9.3 7750 24.3 75.7 245 7 4 25.1 13.8 | 24.0 75.2 210 8 4 12.5 6.9 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