717 UXUS97 KBOU 120045 SRGBOU Soaring Forecast National Weather Service Denver/Boulder, Colorado 1745 MST Monday, November 11, 2024 This forecast is for Tuesday, November 12, 2024: If the trigger temperature of 65.1 F/18.4 C is reached...then Thermal Soaring Index....................... Poor Maximum rate of lift........................ 140 ft/min (0.7 m/s) Maximum height of thermals.................. 7030 ft MSL (1716 ft AGL) Forecast maximum temperature................... 57.0 F/14.3 C Time of trigger temperature.................... None 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................. 6448 ft MSL (1134 ft AGL) Thermal soaring outlook for Wednesday 11/13.... Good Wave Soaring Index............................. Poor Wave Soaring Index trend (to 1700 MST)......... No change Height of stable layer (12-18K ft MSL)......... None Weak PVA/NVA (through 1700 MST)................ Neither Potential height of wave....................... 21811 ft MSL (16497 ft AGL) Wave soaring outlook for Wednesday 11/13....... Good Remarks... None Sunrise/Sunset.................... 06:41:38 / 16:45:44 MST Total possible sunshine........... 10 hr 4 min 6 sec (604 min 6 sec) Altitude of sun at 11:43:41 MST... 32.13 degrees Upper air data from numerical model forecast valid on 11/12/2024 at 0500 MST Freezing level.................. 5591 ft MSL (277 ft AGL) Additional freezing level....... 12093 ft MSL (6779 ft AGL) Convective condensation level... 16770 ft MSL (11456 ft AGL) Lifted condensation level....... 12901 ft MSL (7587 ft AGL) Lifted index.................... +4.9 K index......................... -3.3 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 -60.7 -77.3 240 63 33 3.1 1.7 M M M M M 45000 -56.0 -68.8 235 78 40 2.3 1.3 M M M M M 40000 -52.4 -62.3 235 74 38 2.4 1.3 M M M M M 38000 -51.1 -60.0 235 72 37 2.0 1.1 M M M M M 36000 -49.9 -57.8 240 69 36 2.0 1.1 M M M M M 34000 -48.3 -54.9 240 65 33 5.5 3.0 M M M M M 32000 -44.7 -48.5 235 50 26 5.3 2.9 M M M M M 30000 -41.5 -42.7 235 39 20 5.6 3.1 34.3 93.7 15.4 M M 29000 -39.8 -39.6 230 35 18 5.6 3.1 32.6 90.6 14.2 M M 28000 -38.1 -36.6 225 31 16 5.6 3.1 31.0 87.8 13.2 M M 27000 -36.4 -33.5 215 28 14 7.3 4.0 29.6 85.3 12.3 M M 26000 -34.0 -29.2 215 28 15 8.1 4.4 28.8 83.9 11.8 M M 25000 -31.5 -24.7 215 29 15 8.1 4.4 28.2 82.8 11.4 M M 24000 -29.1 -20.4 215 30 15 8.4 4.6 27.7 81.9 11.2 M M 23000 -26.5 -15.7 220 31 16 8.9 4.9 27.3 81.1 10.9 M M 22000 -23.8 -10.8 220 32 16 8.9 4.9 27.0 80.5 10.8 M M 21000 -21.2 -6.2 225 33 17 8.6 4.7 26.7 80.1 10.7 M M 20000 -18.6 -1.5 220 31 16 8.5 4.7 26.2 79.2 10.4 M M 19500 -17.3 0.9 220 31 16 8.5 4.7 26.0 78.8 10.3 M M 19000 -16.0 3.2 220 30 15 8.5 4.7 25.8 78.5 10.2 M M 18500 -14.7 5.5 220 29 15 8.0 4.4 25.7 78.2 10.1 M M 18000 -13.6 7.5 220 28 14 7.4 4.1 25.2 77.4 9.8 M M 17500 -12.0 10.4 220 26 14 7.6 4.2 24.6 76.4 9.4 M M 17000 -10.8 12.6 220 25 13 7.9 4.3 24.3 75.8 9.1 M M 16500 -9.6 14.7 225 24 12 7.9 4.3 24.0 75.2 8.9 M M 16000 -8.4 16.9 225 23 12 8.2 4.5 23.7 74.7 8.7 M M 15500 -7.2 19.0 225 22 11 8.2 4.5 23.4 74.2 8.5 M M 15000 -6.0 21.2 230 20 10 7.6 4.2 23.1 73.6 8.3 M M 14500 -4.9 23.2 230 19 10 7.5 4.1 22.8 73.0 8.0 M M 14000 -3.8 25.2 230 17 9 7.3 4.0 22.4 72.3 7.7 M M 13500 -2.7 27.1 235 16 8 7.1 3.9 22.0 71.5 7.3 M M 13000 -1.7 28.9 240 15 8 6.9 3.8 21.5 70.8 6.9 M M 12500 -0.7 30.7 240 14 7 6.6 3.6 21.0 69.8 6.5 M M 12000 0.3 32.5 245 13 6 6.9 3.8 20.5 68.9 6.0 M M 11500 1.3 34.3 245 12 6 7.6 4.2 20.1 68.3 5.6 M M 11000 2.4 36.3 250 11 5 7.5 4.1 19.8 67.7 5.3 M M 10500 3.5 38.3 250 10 5 6.9 3.8 19.4 66.9 4.9 M M 10250 4.0 39.2 250 9 5 8.4 4.6 19.2 66.6 4.7 M M 10000 4.7 40.5 250 9 5 9.8 5.4 19.2 66.6 4.7 M M 9750 5.4 41.7 250 8 4 8.2 4.5 19.1 66.4 4.6 M M 9500 5.9 42.6 250 8 4 7.4 4.0 19.0 66.1 4.5 M M 9250 6.5 43.7 255 7 4 7.8 4.3 18.8 65.8 4.3 M M 9000 7.0 44.6 255 7 4 7.0 3.8 18.6 65.5 4.1 M M 8750 7.5 45.5 255 7 3 5.7 3.1 18.3 65.0 3.8 M M 8500 7.8 46.0 255 6 3 5.5 3.0 18.0 64.4 3.5 M M 8250 8.2 46.8 255 6 3 5.6 3.1 17.7 63.8 3.2 M M 8000 8.6 47.5 255 6 3 3.9 2.2 17.3 63.2 2.8 M M 7750 8.7 47.7 260 5 3 1.5 0.8 16.8 62.2 2.2 M M 7500 8.8 47.8 260 5 3 1.7 1.0 16.1 61.0 1.6 M M 7250 8.9 48.0 260 5 2 -0.2 -0.1 15.5 59.9 1.0 M M 7000 8.7 47.7 265 4 2 -3.7 -2.0 14.6 58.2 0.0 M M 6750 8.3 46.9 275 4 2 -6.8 -3.7 13.4 56.2 -1.1 145 0.7 6500 7.7 45.9 290 4 2 -5.4 -3.0 12.2 53.9 -2.4 155 0.8 6250 7.0 44.6 295 4 2 -19.6 -10.8 10.7 51.3 -3.9 168 0.9 6000 4.9 40.8 280 4 2 -30.2 -16.6 7.8 46.0 -6.8 226 1.1 5750 2.7 36.9 265 4 2 -34.1 -18.7 4.9 40.8 -9.7 283 1.4 5500 -0.4 31.3 225 5 2 -45.9 -25.2 1.0 33.8 -13.5 368 1.9 * * * * * * Numerical weather prediction model forecast data valid * * * * * * 11/12/2024 at 0800 MST | 11/12/2024 at 1100 MST | CAPE... +0.1 LI... +3.9 | CAPE... 0.0 LI... +5.0 CINH... -0.1 K Index... -3.5 | CINH... -0.2 K Index... -4.8 | 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 -59.6 -75.3 230 62 32 3.0 1.7 | -57.7 -71.9 235 57 29 2.8 1.6 45000 -55.0 -67.0 230 81 42 1.3 0.7 | -53.3 -63.9 230 75 39 1.1 0.6 40000 -52.7 -62.9 230 77 40 1.5 0.8 | -51.9 -61.4 235 84 43 0.9 0.5 38000 -51.4 -60.5 230 77 40 2.5 1.4 | -51.2 -60.2 235 83 43 1.3 0.7 36000 -49.9 -57.8 225 79 40 2.5 1.4 | -50.5 -58.9 225 79 41 1.3 0.7 34000 -48.4 -55.1 225 78 40 2.8 1.6 | -49.5 -57.1 220 76 39 3.8 2.1 32000 -46.5 -51.7 225 67 34 2.8 1.5 | -46.8 -52.2 220 70 36 4.0 2.2 30000 -44.0 -47.2 225 57 29 8.0 4.4 | -44.0 -47.2 215 65 34 7.7 4.2 29000 -41.6 -42.9 225 52 27 8.2 4.5 | -41.7 -43.1 215 63 33 7.7 4.2 28000 -39.1 -38.4 220 48 25 8.2 4.5 | -39.4 -38.9 210 62 32 7.7 4.2 27000 -36.6 -33.9 220 43 22 8.2 4.5 | -37.1 -34.8 210 60 31 7.9 4.4 26000 -34.2 -29.6 220 43 22 8.2 4.5 | -34.6 -30.3 210 59 30 8.6 4.7 25000 -31.7 -25.1 220 42 22 8.2 4.5 | -32.0 -25.6 210 58 30 8.6 4.7 24000 -29.3 -20.7 215 41 21 8.2 4.5 | -29.4 -20.9 205 57 29 8.6 4.7 23000 -26.8 -16.2 215 41 21 8.2 4.5 | -27.0 -16.6 205 56 29 8.1 4.5 22000 -24.4 -11.9 210 41 21 8.2 4.5 | -24.5 -12.1 205 55 28 8.2 4.5 21000 -21.9 -7.4 205 41 21 8.2 4.5 | -22.1 -7.8 200 54 28 8.1 4.4 20000 -19.5 -3.1 205 39 20 8.2 4.5 | -19.7 -3.5 200 53 27 8.0 4.4 19500 -18.2 -0.8 200 38 19 8.2 4.5 | -18.5 -1.3 200 52 27 8.0 4.4 19000 -17.0 1.4 200 37 19 8.2 4.5 | -17.3 0.9 200 51 26 8.0 4.4 18500 -15.8 3.6 200 36 19 8.0 4.4 | -16.1 3.0 200 51 26 7.9 4.3 18000 -14.1 6.6 200 34 18 7.6 4.1 | -15.0 5.0 200 49 25 7.0 3.8 17500 -12.9 8.8 200 33 17 7.5 4.1 | -13.4 7.9 200 47 24 7.1 3.9 17000 -11.8 10.8 200 31 16 7.4 4.1 | -12.4 9.7 205 46 24 7.2 3.9 16500 -10.7 12.7 200 30 15 7.4 4.1 | -11.3 11.7 205 45 23 7.2 4.0 16000 -9.6 14.7 205 29 15 7.8 4.3 | -10.2 13.6 205 44 23 6.9 3.8 15500 -8.4 16.9 205 27 14 7.7 4.2 | -9.2 15.4 210 43 22 6.9 3.8 15000 -7.3 18.9 205 26 13 7.7 4.2 | -8.2 17.2 210 42 21 6.7 3.7 14500 -6.1 21.0 210 25 13 7.7 4.2 | -7.2 19.0 215 40 21 6.6 3.6 14000 -5.0 23.0 210 24 12 7.8 4.3 | -6.2 20.8 215 39 20 6.6 3.6 13500 -3.8 25.2 215 23 12 7.8 4.3 | -5.2 22.6 220 36 19 6.8 3.7 13000 -2.6 27.3 215 22 11 7.8 4.3 | -4.2 24.4 220 34 18 6.9 3.8 12500 -1.5 29.3 220 21 11 7.8 4.3 | -3.2 26.2 225 32 17 7.1 3.9 12000 -0.3 31.5 225 21 11 7.7 4.2 | -2.1 28.2 225 30 16 7.1 3.9 11500 0.8 33.4 225 20 10 7.2 3.9 | -1.1 30.0 230 28 15 7.5 4.1 11000 1.8 35.2 230 20 10 7.1 3.9 | 0.0 32.0 230 26 13 7.5 4.1 10500 2.8 37.0 235 18 9 6.2 3.4 | 1.0 33.8 230 23 12 5.8 3.2 10250 3.3 37.9 235 17 9 7.0 3.9 | 1.5 34.7 235 23 12 7.5 4.1 10000 3.9 39.0 235 17 9 8.5 4.7 | 2.2 36.0 230 22 11 10.8 5.9 9750 4.5 40.1 235 16 8 8.2 4.5 | 2.9 37.2 225 21 11 9.4 5.2 9500 5.1 41.2 235 15 8 7.5 4.1 | 3.5 38.3 225 19 10 7.6 4.2 9250 5.6 42.1 235 13 7 8.1 4.5 | 4.1 39.4 225 18 9 7.8 4.3 9000 6.2 43.2 235 12 6 6.5 3.6 | 4.7 40.5 225 17 9 8.9 4.9 8750 6.6 43.9 235 12 6 6.1 3.3 | 5.4 41.7 220 17 9 9.1 5.0 8500 7.1 44.8 235 11 5 7.4 4.1 | 6.0 42.8 215 16 8 8.0 4.4 8250 7.6 45.7 230 10 5 6.9 3.8 | 6.6 43.9 215 16 8 8.4 4.6 8000 8.2 46.8 230 9 4 8.0 4.4 | 7.2 45.0 210 15 8 8.0 4.4 7750 8.7 47.7 230 8 4 6.3 3.5 | 7.8 46.0 210 14 7 7.4 4.0 7500 9.1 48.4 230 7 4 4.3 2.3 | 8.3 46.9 205 14 7 7.1 3.9 7250 9.4 48.9 230 7 3 4.4 2.4 | 8.9 48.0 205 14 7 7.3 4.0 7000 9.6 49.3 230 6 3 3.2 1.8 | 9.3 48.7 200 14 7 5.5 3.0 6750 9.8 49.6 225 7 4 -0.2 -0.1 | 9.7 49.5 200 13 7 3.8 2.1 6500 9.7 49.5 225 7 4 1.2 0.7 | 10.0 50.0 200 12 6 5.1 2.8 6250 9.6 49.3 220 7 4 -8.8 -4.8 | 10.3 50.5 195 12 6 1.6 0.9 6000 8.3 46.9 210 8 4 -20.3 -11.2 | 10.1 50.2 195 11 6 -3.8 -2.1 5750 6.8 44.2 205 10 5 -21.1 -11.6 | 9.6 49.3 190 11 6 -6.6 -3.6 5500 4.7 40.5 205 8 4 -36.7 -20.2 | 9.0 48.2 190 8 4 -3.0 -1.7 11/12/2024 at 1400 MST | 11/12/2024 at 1700 MST | CAPE... +144.1 LI... +0.8 | CAPE... +31.8 LI... -0.1 CINH... -59.9 K Index... +6.2 | CINH... -38.1 K Index... +20.9 | 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 -58.5 -73.3 225 55 28 2.0 1.1 | -57.0 -70.6 235 53 27 3.0 1.7 45000 -55.3 -67.5 220 74 38 2.9 1.6 | -52.5 -62.5 230 71 36 2.9 1.6 40000 -50.7 -59.3 230 76 39 3.1 1.7 | -48.3 -54.9 240 57 29 2.7 1.5 38000 -49.5 -57.1 225 76 39 0.7 0.4 | -47.2 -53.0 235 55 28 0.8 0.4 36000 -49.1 -56.4 220 76 39 0.7 0.4 | -46.7 -52.1 220 60 31 0.8 0.4 34000 -48.6 -55.5 215 76 39 3.0 1.6 | -46.3 -51.3 210 68 35 1.5 0.8 32000 -46.4 -51.5 215 73 37 3.7 2.1 | -44.7 -48.5 205 66 34 2.6 1.4 30000 -43.6 -46.5 210 70 36 6.9 3.8 | -43.2 -45.8 205 64 33 3.4 1.8 29000 -41.6 -42.9 210 70 36 6.7 3.7 | -41.2 -42.2 200 64 33 5.3 2.9 28000 -39.6 -39.3 205 70 36 6.7 3.7 | -39.6 -39.3 200 63 33 5.3 2.9 27000 -37.6 -35.7 205 70 36 6.8 3.7 | -38.0 -36.4 200 63 33 5.3 2.9 26000 -35.1 -31.2 205 69 35 8.8 4.8 | -36.2 -33.2 200 61 32 6.5 3.6 25000 -32.5 -26.5 200 67 34 8.8 4.8 | -34.3 -29.7 195 59 30 6.5 3.6 24000 -29.8 -21.6 200 65 33 8.8 4.8 | -32.3 -26.1 195 56 29 6.5 3.6 23000 -27.3 -17.1 195 61 31 8.5 4.7 | -30.1 -22.2 195 52 27 7.8 4.3 22000 -24.7 -12.5 195 57 29 8.5 4.7 | -27.8 -18.0 195 47 24 7.9 4.3 21000 -22.1 -7.8 190 53 27 8.3 4.6 | -25.4 -13.7 190 41 21 8.4 4.6 20000 -20.1 -4.2 195 51 26 6.6 3.6 | -23.9 -11.0 195 30 16 4.2 2.3 19500 -19.1 -2.4 195 51 26 6.6 3.6 | -23.3 -9.9 195 23 12 4.2 2.3 19000 -18.1 -0.6 200 50 26 6.6 3.6 | -22.7 -8.9 200 17 9 4.2 2.3 18500 -17.1 1.2 205 50 26 6.7 3.7 | -22.1 -7.8 215 10 5 4.0 2.2 18000 -16.2 2.8 210 50 26 5.5 3.0 | -21.2 -6.2 230 6 3 8.9 4.9 17500 -15.4 4.3 210 48 25 5.6 3.1 | -19.8 -3.6 210 4 2 9.5 5.2 17000 -14.6 5.7 210 47 24 5.8 3.2 | -18.4 -1.1 170 3 2 9.3 5.1 16500 -13.7 7.3 215 44 22 6.1 3.3 | -17.1 1.2 150 3 2 8.9 4.9 16000 -12.8 9.0 215 41 21 6.1 3.4 | -15.8 3.6 140 4 2 9.0 5.0 15500 -11.4 11.5 225 38 19 6.3 3.5 | -14.7 5.5 125 4 2 6.6 3.6 15000 -10.5 13.1 230 37 19 6.5 3.6 | -13.2 8.2 090 4 2 6.7 3.7 14500 -9.5 14.9 230 33 17 6.8 3.8 | -12.2 10.0 065 4 2 6.5 3.6 14000 -8.6 16.5 235 29 15 7.1 3.9 | -11.3 11.7 040 5 3 6.5 3.6 13500 -7.4 18.7 240 25 13 9.0 4.9 | -10.2 13.6 030 7 3 7.6 4.2 13000 -6.1 21.0 240 21 11 8.9 4.9 | -9.1 15.6 020 8 4 7.6 4.2 12500 -4.8 23.4 245 18 9 8.3 4.5 | -8.0 17.6 005 9 5 7.0 3.8 12000 -3.6 25.5 245 16 8 8.3 4.5 | -7.0 19.4 355 10 5 7.1 3.9 11500 -2.3 27.9 245 14 7 8.8 4.9 | -6.0 21.2 335 12 6 6.7 3.7 11000 -1.0 30.2 245 12 6 8.8 4.8 | -5.0 23.0 325 15 7 7.0 3.8 10500 0.3 32.5 240 12 6 8.6 4.7 | -4.1 24.6 310 18 9 4.8 2.6 10250 1.0 33.8 240 11 6 8.9 4.9 | -3.7 25.3 305 21 11 5.1 2.8 10000 1.7 35.1 235 12 6 10.0 5.5 | -3.3 26.1 305 23 12 6.5 3.6 9750 2.4 36.3 230 12 6 9.0 5.0 | -2.8 27.0 300 26 13 7.8 4.3 9500 3.0 37.4 230 12 6 7.9 4.3 | -2.2 28.0 300 28 14 7.5 4.1 9250 3.6 38.5 230 12 6 8.2 4.5 | -1.6 29.1 300 29 15 7.7 4.2 9000 4.2 39.6 230 12 6 8.2 4.5 | -1.1 30.0 295 31 16 7.5 4.1 8750 4.8 40.6 230 13 6 7.7 4.2 | -0.5 31.1 295 32 17 8.3 4.5 8500 5.3 41.5 230 13 7 7.4 4.1 | 0.2 32.4 295 32 17 9.3 5.1 8250 5.8 42.4 225 13 7 6.8 3.8 | 0.8 33.4 295 33 17 8.2 4.5 8000 6.3 43.3 225 14 7 9.5 5.2 | 1.5 34.7 295 33 17 11.5 6.3 7750 7.1 44.8 220 14 7 8.6 4.7 | 2.5 36.5 295 33 17 11.3 6.2 7500 7.5 45.5 220 14 7 5.3 2.9 | 3.1 37.6 295 33 17 8.1 4.4 7250 8.0 46.4 215 13 7 6.2 3.4 | 3.8 38.8 295 33 17 9.0 4.9 7000 8.4 47.1 215 13 7 5.8 3.2 | 4.5 40.1 295 34 17 9.6 5.3 6750 8.7 47.7 210 12 6 3.5 1.9 | 5.2 41.4 295 33 17 9.4 5.1 6500 8.8 47.8 210 9 5 2.3 1.3 | 5.9 42.6 295 33 17 9.2 5.0 6250 8.9 48.0 205 7 4 2.3 1.3 | 6.5 43.7 295 32 17 7.4 4.0 6000 9.0 48.2 205 5 2 0.9 0.5 | 6.9 44.4 295 29 15 4.8 2.6 5750 8.9 48.0 220 2 1 1.7 1.0 | 7.1 44.8 295 25 13 5.0 2.8 5500 9.1 48.4 275 1 1 7.1 3.9 | 7.4 45.3 290 18 9 2.8 1.5 ________________________________________________________________________________ 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