Soaring Guidance
Issued by NWS Denver/Boulder, CO
Issued by NWS Denver/Boulder, CO
431 UXUS97 KBOU 141303 SRGBOU Soaring Forecast National Weather Service Denver/Boulder, Colorado 0702 MDT Sunday, July 14, 2024 This forecast is for Sunday, July 14, 2024: If the trigger temperature of 90.7 F/32.6 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1815 ft/min (9.2 m/s) Maximum height of thermals.................. 23519 ft MSL (18194 ft AGL) Forecast maximum temperature................... 101.0 F/38.8 C Time of trigger temperature.................... 0945 MDT Time of overdevelopment........................ 1700 MDT Middle/high clouds during soaring window....... None Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 16916 ft MSL (11591 ft AGL) Thermal soaring outlook for Monday 07/15....... Excellent Wave Soaring Index............................. Poor Wave Soaring Index trend (to 1800 MDT)......... No change Height of stable layer (12-18K ft MSL)......... None Weak PVA/NVA (through 1800 MDT)................ Neither Potential height of wave....................... 36319 ft MSL (30994 ft AGL) Wave soaring outlook for Monday 07/15.......... Poor Remarks... Sunrise/Sunset.................... 05:43:56 / 20:27:00 MDT Total possible sunshine........... 14 hr 43 min 4 sec (883 min 4 sec) Altitude of sun at 13:05:28 MDT... 71.70 degrees Upper air data from numerical model forecast valid on 07/14/2024 at 0600 MDT Freezing level.................. 17042 ft MSL (11717 ft AGL) Convective condensation level... 19000 ft MSL (13675 ft AGL) Lifted condensation level....... 20197 ft MSL (14872 ft AGL) Lifted index.................... -3.9 K index......................... +20.7 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 -60.8 -77.4 260 14 7 0.7 0.4 M M M M M 45000 -58.0 -72.4 265 16 8 3.7 2.0 M M M M M 40000 -51.8 -61.2 310 19 10 6.0 3.3 M M M M M 38000 -48.3 -54.9 305 26 13 6.0 3.3 M M M M M 36000 -44.7 -48.5 305 32 16 6.3 3.4 M M M M M 34000 -40.5 -40.9 300 25 13 7.0 3.8 M M M M M 32000 -35.8 -32.4 285 17 9 8.3 4.5 45.3 113.6 5.2 M M 30000 -30.8 -23.4 280 14 7 8.5 4.6 44.1 111.3 4.3 M M 29000 -28.3 -18.9 275 12 6 8.4 4.6 43.7 110.6 4.0 M M 28000 -25.9 -14.6 275 11 6 7.3 4.0 43.0 109.5 3.6 M M 27000 -23.7 -10.7 275 11 6 7.3 4.0 42.0 107.6 2.8 M M 26000 -21.5 -6.7 275 12 6 7.4 4.0 41.2 106.1 2.1 M M 25000 -19.4 -2.9 280 12 6 7.0 3.8 40.3 104.6 1.4 M M 24000 -17.4 0.7 280 13 6 6.9 3.8 39.2 102.5 0.5 M M 23000 -15.3 4.5 285 13 7 6.9 3.8 38.2 100.7 -0.4 1770 9.0 22000 -13.2 8.2 290 14 7 8.5 4.6 37.3 99.2 -1.2 1677 8.5 21000 -10.7 12.7 290 14 7 8.5 4.7 36.8 98.3 -1.7 1573 8.0 20000 -8.2 17.2 285 14 7 8.6 4.7 36.4 97.6 -2.1 1468 7.5 19500 -7.0 19.4 285 14 7 8.8 4.8 36.3 97.3 -2.3 1416 7.2 19000 -5.6 21.9 285 13 7 9.0 5.0 36.1 97.0 -2.4 1361 6.9 18500 -4.3 24.3 285 13 7 9.0 5.0 36.0 96.8 -2.5 1306 6.6 18000 -2.9 26.8 285 13 7 9.1 5.0 35.9 96.6 -2.7 1251 6.4 17500 -0.9 30.4 280 13 7 9.2 5.0 35.7 96.3 -2.9 1168 5.9 17000 0.4 32.7 280 13 7 8.9 4.9 35.6 96.1 -3.0 1113 5.7 16500 1.7 35.1 280 14 7 8.9 4.9 35.5 95.8 -3.2 1059 5.4 16000 3.1 37.6 280 14 7 9.0 4.9 35.3 95.6 -3.3 1004 5.1 15500 4.4 39.9 280 14 7 9.0 4.9 35.2 95.4 -3.5 950 4.8 15000 5.7 42.3 280 14 7 9.0 5.0 35.1 95.2 -3.6 895 4.5 14500 7.1 44.8 280 14 7 9.3 5.1 35.0 95.0 -3.7 839 4.3 14000 8.5 47.3 285 14 7 9.3 5.1 34.9 94.8 -3.8 784 4.0 13500 9.8 49.6 285 14 7 9.1 5.0 34.8 94.7 -3.9 728 3.7 13000 11.2 52.2 285 14 7 9.1 5.0 34.7 94.5 -4.1 672 3.4 12500 12.6 54.7 285 14 7 9.3 5.1 34.6 94.3 -4.2 616 3.1 12000 13.9 57.0 285 13 7 9.3 5.1 34.6 94.2 -4.3 560 2.8 11500 15.3 59.5 285 13 7 9.1 5.0 34.5 94.1 -4.4 504 2.6 11000 16.7 62.1 285 12 6 9.2 5.0 34.4 93.8 -4.5 449 2.3 10500 17.8 64.0 285 12 6 3.4 1.9 34.1 93.3 -4.8 400 2.0 10250 18.1 64.6 290 12 6 6.7 3.7 33.5 92.4 -5.3 385 2.0 10000 18.9 66.0 285 12 6 12.3 6.8 33.6 92.5 -5.3 353 1.8 9750 19.7 67.5 285 12 6 10.6 5.8 33.7 92.7 -5.2 322 1.6 9500 20.4 68.7 280 11 6 7.1 3.9 33.7 92.7 -5.2 294 1.5 9250 20.7 69.3 280 11 6 5.3 2.9 33.4 92.1 -5.6 275 1.4 9000 21.2 70.2 280 11 6 8.0 4.4 33.1 91.7 -5.8 253 1.3 8750 21.8 71.2 280 11 6 7.9 4.4 33.0 91.5 -6.0 227 1.2 8500 22.3 72.1 280 11 6 5.4 3.0 32.8 91.1 -6.2 205 1.0 8250 22.7 72.9 280 11 6 3.8 2.1 32.4 90.3 -6.7 188 1.0 8000 23.0 73.4 280 11 6 5.6 3.1 32.0 89.6 -7.1 171 0.9 7750 23.5 74.3 280 11 6 6.2 3.4 31.7 89.1 -7.3 149 0.8 7500 23.8 74.8 285 12 6 4.2 2.3 31.4 88.4 -7.7 131 0.7 7250 24.1 75.4 285 12 6 3.3 1.8 30.9 87.6 -8.2 116 0.6 7000 24.3 75.7 290 12 6 4.9 2.7 30.4 86.8 -8.7 101 0.5 6750 24.7 76.5 285 12 6 4.6 2.5 30.1 86.2 -9.1 83 0.4 6500 24.9 76.8 280 11 6 2.4 1.3 29.6 85.3 -9.7 69 0.4 6250 25.1 77.2 280 11 6 3.0 1.6 29.1 84.3 -10.2 57 0.3 6000 25.2 77.4 275 10 5 0.9 0.5 28.5 83.3 -10.8 44 0.2 5750 24.8 76.6 265 9 5 -14.1 -7.8 27.4 81.3 -12.0 49 0.3 5500 23.0 73.4 245 6 3 -32.3 -17.7 24.8 76.7 -14.6 97 0.5 * * * * * * Numerical weather prediction model forecast data valid * * * * * * 07/14/2024 at 0900 MDT | 07/14/2024 at 1200 MDT | CAPE... +93.4 LI... +0.5 | CAPE... +314.1 LI... -0.6 CINH... -110.6 K Index... +20.7 | CINH... -15.1 K Index... +22.1 | 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 -61.5 -78.7 270 13 7 1.3 0.7 | -61.7 -79.1 275 15 8 1.3 0.7 45000 -57.8 -72.0 270 18 9 4.2 2.3 | -58.1 -72.6 280 19 10 4.0 2.2 40000 -51.2 -60.2 295 15 8 5.5 3.0 | -51.7 -61.1 280 17 9 5.6 3.1 38000 -47.9 -54.2 320 21 11 5.5 3.0 | -48.3 -54.9 305 19 10 5.6 3.1 36000 -44.6 -48.3 330 29 15 6.0 3.3 | -44.9 -48.8 320 24 12 6.6 3.6 34000 -40.5 -40.9 320 26 13 7.0 3.9 | -40.3 -40.5 320 23 12 7.8 4.3 32000 -35.7 -32.3 305 23 12 8.0 4.4 | -35.6 -32.1 315 22 11 8.2 4.5 30000 -30.9 -23.6 290 18 9 8.0 4.4 | -30.3 -22.5 300 19 10 7.9 4.3 29000 -28.5 -19.3 285 16 8 8.0 4.4 | -28.0 -18.4 295 17 9 7.9 4.3 28000 -26.2 -15.2 275 15 8 7.4 4.1 | -25.7 -14.3 285 17 9 7.5 4.1 27000 -24.0 -11.2 270 15 8 7.4 4.1 | -23.4 -10.1 280 16 8 7.5 4.1 26000 -21.8 -7.2 265 15 8 7.4 4.1 | -21.2 -6.2 275 15 8 7.5 4.1 25000 -19.6 -3.3 260 15 8 7.5 4.1 | -19.0 -2.2 270 15 8 7.3 4.0 24000 -17.4 0.7 260 15 8 7.6 4.2 | -16.9 1.6 265 15 8 7.3 4.0 23000 -15.1 4.8 260 15 8 7.6 4.2 | -14.7 5.5 265 15 8 7.3 4.0 22000 -12.9 8.8 260 14 7 8.0 4.4 | -12.5 9.5 265 15 8 7.8 4.3 21000 -10.5 13.1 265 14 7 8.0 4.4 | -10.3 13.5 265 14 7 7.8 4.3 20000 -8.2 17.2 270 13 7 8.0 4.4 | -8.0 17.6 270 12 6 7.9 4.3 19500 -7.0 19.4 270 13 7 8.4 4.6 | -6.9 19.6 270 12 6 8.4 4.6 19000 -5.7 21.7 270 13 7 8.8 4.8 | -5.6 21.9 275 11 6 8.8 4.8 18500 -4.4 24.1 270 13 7 8.8 4.9 | -4.3 24.3 280 11 6 8.8 4.8 18000 -3.1 26.4 275 13 7 9.1 5.0 | -3.0 26.6 285 11 6 8.7 4.8 17500 -1.1 30.0 275 13 7 9.1 5.0 | -1.7 28.9 290 11 6 8.8 4.8 17000 0.3 32.5 280 13 7 9.1 5.0 | -0.4 31.3 295 11 6 9.0 4.9 16500 1.6 34.9 285 12 6 9.1 5.0 | 0.9 33.6 295 11 6 9.1 5.0 16000 3.0 37.4 285 12 6 9.1 5.0 | 2.9 37.2 300 11 6 9.1 5.0 15500 4.3 39.7 290 12 6 9.1 5.0 | 4.3 39.7 305 11 6 9.1 5.0 15000 5.7 42.3 295 12 6 9.1 5.0 | 5.7 42.3 305 11 6 9.1 5.0 14500 7.0 44.6 300 13 7 9.0 5.0 | 7.0 44.6 310 11 6 9.1 5.0 14000 8.3 46.9 305 13 7 9.0 5.0 | 8.3 46.9 315 11 6 9.1 5.0 13500 9.7 49.5 310 14 7 8.9 4.9 | 9.7 49.5 315 11 5 9.1 5.0 13000 11.0 51.8 310 15 8 8.9 4.9 | 11.0 51.8 320 10 5 9.1 5.0 12500 12.3 54.1 315 16 8 9.1 5.0 | 12.4 54.3 325 10 5 9.3 5.1 12000 13.7 56.7 315 16 8 9.1 5.0 | 13.8 56.8 330 10 5 9.3 5.1 11500 15.0 59.0 320 17 9 9.1 5.0 | 15.2 59.4 330 10 5 9.5 5.2 11000 16.4 61.5 320 17 9 9.4 5.1 | 16.6 61.9 330 10 5 10.0 5.5 10500 17.5 63.5 320 17 9 3.4 1.9 | 17.6 63.7 330 11 5 3.6 2.0 10250 17.8 64.0 320 18 9 8.0 4.4 | 18.0 64.4 330 11 5 9.4 5.2 10000 18.7 65.7 320 17 9 13.1 7.2 | 19.0 66.2 330 10 5 13.9 7.7 9750 19.6 67.3 320 17 9 11.1 6.1 | 19.9 67.8 330 10 5 11.9 6.5 9500 20.3 68.5 320 16 8 7.3 4.0 | 20.7 69.3 330 10 5 7.7 4.2 9250 20.7 69.3 320 16 8 6.5 3.5 | 21.2 70.2 330 10 5 7.9 4.3 9000 21.4 70.5 320 16 8 9.8 5.4 | 22.0 71.6 330 10 5 12.3 6.7 8750 22.1 71.8 315 16 8 9.7 5.3 | 22.9 73.2 330 10 5 11.6 6.4 8500 22.7 72.9 315 15 8 7.5 4.1 | 23.6 74.5 330 10 5 9.5 5.2 8250 23.3 73.9 315 15 8 6.3 3.4 | 24.3 75.7 330 10 5 8.1 4.4 8000 23.8 74.8 320 15 8 8.3 4.6 | 25.0 77.0 330 10 5 11.2 6.2 7750 24.4 75.9 315 14 7 8.4 4.6 | 25.9 78.6 330 10 5 11.8 6.5 7500 24.9 76.8 315 14 7 5.9 3.3 | 26.6 79.9 330 10 5 8.8 4.8 7250 25.3 77.5 315 13 7 4.8 2.6 | 27.2 81.0 330 10 5 7.4 4.1 7000 25.8 78.4 315 13 6 8.3 4.5 | 27.9 82.2 330 10 5 11.7 6.4 6750 26.5 79.7 305 11 6 8.2 4.5 | 28.9 84.0 330 9 5 13.4 7.4 6500 26.8 80.2 305 10 5 4.6 2.5 | 29.7 85.5 330 9 5 10.0 5.5 6250 27.2 81.0 300 9 5 5.0 2.7 | 30.5 86.9 325 9 5 10.6 5.8 6000 27.5 81.5 295 8 4 6.2 3.4 | 31.3 88.3 325 9 4 10.0 5.5 5750 28.2 82.8 295 7 3 12.2 6.7 | 32.2 90.0 325 9 5 17.3 9.5 5500 29.3 84.7 290 5 3 17.6 9.6 | 34.0 93.2 325 9 4 30.5 16.7 07/14/2024 at 1500 MDT | 07/14/2024 at 1800 MDT | CAPE... +354.7 LI... -0.8 | CAPE... +325.8 LI... -0.8 CINH... -5.3 K Index... +23.8 | CINH... -52.3 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 -61.5 -78.7 295 14 7 0.9 0.5 | -61.1 -78.0 305 14 7 1.2 0.7 45000 -58.6 -73.5 300 17 9 3.5 1.9 | -58.5 -73.3 300 18 9 2.4 1.3 40000 -52.6 -62.7 285 25 13 6.5 3.6 | -53.5 -64.3 280 30 15 8.0 4.4 38000 -48.7 -55.7 295 26 13 6.5 3.6 | -48.7 -55.7 285 29 15 8.0 4.4 36000 -44.8 -48.6 305 27 14 7.3 4.0 | -43.9 -47.0 295 30 15 7.9 4.3 34000 -39.8 -39.6 295 26 13 8.3 4.5 | -39.3 -38.7 290 27 14 7.7 4.2 32000 -34.3 -29.7 285 24 12 8.3 4.5 | -34.1 -29.4 290 25 13 8.2 4.5 30000 -29.7 -21.5 285 22 12 7.7 4.3 | -29.4 -20.9 290 24 12 7.8 4.3 29000 -27.3 -17.1 285 22 11 7.7 4.2 | -27.1 -16.8 290 23 12 7.8 4.3 28000 -25.2 -13.4 285 20 10 6.7 3.7 | -24.9 -12.8 290 22 11 6.8 3.7 27000 -23.2 -9.8 280 18 9 6.7 3.7 | -22.9 -9.2 285 20 10 6.9 3.8 26000 -21.2 -6.2 280 16 8 6.7 3.7 | -20.9 -5.6 285 18 9 6.9 3.8 25000 -19.2 -2.6 275 14 7 7.2 4.0 | -18.8 -1.8 285 16 8 7.3 4.0 24000 -17.1 1.2 275 14 7 7.3 4.0 | -16.7 1.9 285 14 7 7.4 4.1 23000 -14.9 5.2 280 14 7 7.3 4.0 | -14.5 5.9 285 13 7 7.4 4.1 22000 -12.7 9.1 280 15 7 8.3 4.6 | -12.3 9.9 290 12 6 8.1 4.4 21000 -10.3 13.5 280 14 7 8.3 4.6 | -9.9 14.2 285 9 5 8.2 4.5 20000 -7.9 17.8 285 13 7 8.4 4.6 | -7.6 18.3 285 6 3 8.2 4.5 19500 -6.7 19.9 285 13 6 8.6 4.7 | -6.4 20.5 285 5 2 8.3 4.5 19000 -5.3 22.5 285 12 6 8.9 4.9 | -5.2 22.6 280 3 2 8.3 4.6 18500 -4.0 24.8 290 11 5 8.9 4.9 | -3.9 25.0 265 2 1 8.2 4.5 18000 -2.7 27.1 290 10 5 9.2 5.0 | -2.0 28.4 255 1 1 9.1 5.0 17500 -1.3 29.7 295 9 4 9.2 5.0 | -0.7 30.7 275 1 0 9.1 5.0 17000 0.7 33.3 300 7 4 9.2 5.0 | 0.7 33.3 305 1 0 9.5 5.2 16500 2.1 35.8 305 7 3 9.2 5.0 | 2.1 35.8 325 1 1 9.5 5.2 16000 3.4 38.1 310 6 3 9.3 5.1 | 3.5 38.3 335 1 1 9.5 5.2 15500 4.8 40.6 310 6 3 9.4 5.1 | 4.9 40.8 330 2 1 9.4 5.2 15000 6.2 43.2 315 6 3 9.4 5.2 | 6.3 43.3 330 3 1 9.4 5.2 14500 7.6 45.7 315 6 3 9.5 5.2 | 7.7 45.9 325 3 2 9.2 5.1 14000 9.0 48.2 315 6 3 9.5 5.2 | 9.1 48.4 320 4 2 9.2 5.1 13500 10.4 50.7 320 6 3 9.6 5.3 | 10.4 50.7 320 5 2 9.1 5.0 13000 11.9 53.4 320 6 3 9.6 5.3 | 11.8 53.2 315 5 3 9.1 5.0 12500 13.3 55.9 320 6 3 9.7 5.3 | 13.1 55.6 310 6 3 9.0 5.0 12000 14.7 58.5 320 6 3 9.7 5.3 | 14.5 58.1 305 7 4 9.0 4.9 11500 16.2 61.2 320 6 3 9.8 5.4 | 15.8 60.4 305 8 4 9.0 4.9 11000 17.6 63.7 320 6 3 10.2 5.6 | 17.2 63.0 300 8 4 8.8 4.8 10500 18.8 65.8 320 7 3 4.4 2.4 | 18.5 65.3 300 9 5 5.1 2.8 10250 19.2 66.6 320 7 4 9.4 5.1 | 18.7 65.7 300 10 5 7.0 3.8 10000 20.2 68.4 320 7 4 13.5 7.4 | 19.6 67.3 295 10 5 11.8 6.5 9750 21.1 70.0 320 7 3 12.5 6.8 | 20.4 68.7 295 10 5 11.1 6.1 9500 21.9 71.4 320 7 3 8.9 4.9 | 21.2 70.2 290 10 5 8.7 4.8 9250 22.5 72.5 325 7 4 8.5 4.6 | 21.7 71.1 290 11 6 7.2 4.0 9000 23.3 73.9 325 7 4 11.8 6.5 | 22.3 72.1 290 11 6 9.4 5.2 8750 24.2 75.6 320 7 4 11.4 6.2 | 23.0 73.4 285 11 6 9.4 5.1 8500 25.0 77.0 320 7 4 9.9 5.4 | 23.7 74.7 280 12 6 9.1 5.0 8250 25.6 78.1 325 7 4 8.7 4.8 | 24.3 75.7 280 12 6 8.9 4.9 8000 26.3 79.3 325 7 4 10.1 5.5 | 25.0 77.0 280 13 7 8.6 4.7 7750 27.1 80.8 320 7 4 10.5 5.7 | 25.6 78.1 275 13 7 8.2 4.5 7500 27.9 82.2 320 7 4 9.3 5.1 | 26.2 79.2 270 13 7 8.3 4.5 7250 28.5 83.3 320 7 4 8.2 4.5 | 26.7 80.1 270 13 7 8.0 4.4 7000 29.2 84.6 325 7 4 10.7 5.9 | 27.3 81.1 275 13 7 8.7 4.8 6750 30.1 86.2 320 7 4 12.8 7.0 | 28.0 82.4 270 13 7 10.6 5.8 6500 31.0 87.8 320 7 3 10.7 5.9 | 28.8 83.8 270 13 6 11.1 6.1 6250 31.8 89.2 320 7 4 10.8 5.9 | 29.7 85.5 270 12 6 11.7 6.4 6000 32.5 90.5 320 7 4 8.4 4.6 | 30.5 86.9 270 12 6 9.3 5.1 5750 33.3 91.9 320 6 3 14.9 8.2 | 31.2 88.2 270 12 6 11.3 6.2 5500 35.0 95.0 320 6 3 33.2 18.2 | 32.4 90.3 270 11 6 22.4 12.3 ________________________________________________________________________________ This product is issued twice per day, once by approximately 0630 MST/0730 MDT (1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 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 old Stapleton Airport site in Denver, Colorado at North Latitude: 39 deg 46 min 5.016 sec West Longitude: 104 deg 52 min 9.984 sec Elevation: 5285 feet (1611 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. CINH (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