Soaring Guidance
Issued by NWS Grand Junction, CO
Issued by NWS Grand Junction, CO
573 UXUS97 KGJT 041307 SRGGJT Soaring Forecast National Weather Service Grand Junction, Colorado 707 AM MDT Saturday, May 4, 2024 This forecast is for Saturday, May 4, 2024: If the trigger temperature of 60.8 F/16.0 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 995 ft/min (5.1 m/s) Maximum height of thermals.................. 17173 ft MSL (12334 ft AGL) Forecast maximum temperature................... 78.0 F/26.0 C Time of trigger temperature.................... 0945 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................. 14153 ft MSL (9313 ft AGL) Thermal soaring outlook for Sunday 05/05....... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 06:11:18 / 20:10:24 MDT Total possible sunshine........... 13 hr 59 min 6 sec (839 min 6 sec) Altitude of sun at 13:10:51 MDT... 67.04 degrees Upper air data from rawinsonde observation taken on 05/04/2024 at 0600 MDT Freezing level.................. 10732 ft MSL (5893 ft AGL) Convective condensation level... 18144 ft MSL (13305 ft AGL) Lifted condensation level....... 17848 ft MSL (13009 ft AGL) Lifted index.................... -0.9 K index......................... +1.7 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 -57.1 -70.8 255 40 21 2.8 1.5 105.1 221.2 45.4 M M 45000 -55.2 -67.4 260 40 21 2.0 1.1 83.7 182.6 35.5 M M 40000 -58.0 -72.4 250 45 23 -5.8 -3.2 56.2 133.2 20.0 M M 38000 -59.4 -74.9 245 41 21 2.1 1.2 45.3 113.5 13.2 M M 36000 -56.7 -70.1 240 37 19 5.8 3.2 40.5 104.9 10.3 M M 34000 -52.1 -61.8 245 33 17 7.8 4.3 37.6 99.7 8.6 M M 32000 -47.7 -53.9 245 23 12 6.7 3.7 35.6 96.1 7.3 M M 30000 -43.3 -45.9 255 19 10 7.7 4.2 33.8 92.8 6.1 M M 29000 -40.8 -41.4 240 18 9 8.2 4.5 33.2 91.7 5.8 M M 28000 -38.3 -36.9 260 19 10 8.4 4.6 32.5 90.6 5.4 M M 27000 -35.8 -32.4 255 16 8 8.6 4.7 32.1 89.7 5.1 M M 26000 -33.2 -27.8 240 22 11 8.5 4.6 31.6 88.9 4.8 M M 25000 -30.8 -23.4 240 22 11 8.0 4.4 31.0 87.8 4.3 M M 24000 -28.4 -19.1 250 24 12 7.1 3.9 30.3 86.5 3.8 M M 23000 -26.5 -15.7 260 23 12 6.4 3.5 29.1 84.4 2.9 M M 22000 -24.1 -11.4 270 19 10 8.2 4.5 28.4 83.1 2.3 M M 21000 -21.4 -6.5 265 17 9 8.9 4.9 28.2 82.8 2.2 M M 20000 -18.7 -1.7 275 21 11 8.9 4.9 27.9 82.3 2.0 M M 19500 -17.4 0.7 275 19 10 8.9 4.9 27.8 82.0 1.8 M M 19000 -16.0 3.2 275 20 11 8.9 4.9 27.6 81.7 1.7 M M 18500 -14.0 6.8 265 25 13 8.8 4.8 27.4 81.3 1.5 M M 18000 -12.7 9.1 265 26 14 6.7 3.7 27.2 81.0 1.4 M M 17500 -12.2 10.0 270 27 14 1.9 1.1 26.1 79.0 0.5 M M 17000 -11.5 11.3 280 27 14 8.4 4.6 25.2 77.4 -0.3 971 4.9 16500 -10.2 13.6 270 26 13 7.1 3.9 25.0 77.0 -0.5 918 4.7 16000 -9.3 15.3 260 29 15 5.9 3.2 24.4 75.9 -1.0 876 4.4 15500 -8.4 16.9 255 32 16 6.1 3.4 23.8 74.8 -1.6 835 4.2 15000 -7.5 18.5 250 35 18 6.5 3.6 23.2 73.7 -2.2 794 4.0 14500 -6.6 20.1 255 35 18 7.6 4.2 22.7 72.9 -2.8 751 3.8 14000 -5.5 22.1 250 35 18 7.5 4.1 22.4 72.3 -3.2 704 3.6 13500 -4.3 24.3 255 32 16 7.6 4.1 22.0 71.6 -3.5 654 3.3 13000 -3.1 26.4 265 27 14 5.9 3.3 21.7 71.0 -3.7 602 3.1 12500 -2.5 27.5 275 27 14 4.3 2.3 20.8 69.4 -4.6 570 2.9 12000 -2.0 28.4 280 27 14 4.3 2.3 19.9 67.8 -5.6 539 2.7 11500 -1.4 29.5 280 25 13 4.8 2.6 19.0 66.2 -6.5 507 2.6 11000 -0.5 31.1 280 17 9 6.1 3.4 18.3 65.0 -7.1 465 2.4 10500 0.5 32.9 285 12 6 5.8 3.2 17.8 64.0 -7.6 421 2.1 10250 0.9 33.6 285 7 4 7.4 4.0 17.5 63.5 -7.9 400 2.0 10000 1.6 34.9 280 6 3 8.0 4.4 17.4 63.2 -8.0 374 1.9 9750 2.1 35.8 235 5 2 7.0 3.8 17.1 62.9 -8.3 351 1.8 9500 2.6 36.7 200 7 4 7.3 4.0 16.9 62.5 -8.5 328 1.7 9250 3.1 37.6 185 11 6 7.2 4.0 16.7 62.1 -8.8 305 1.5 9000 3.6 38.5 175 16 8 7.2 3.9 16.6 61.8 -9.0 282 1.4 8750 4.1 39.4 170 16 8 7.6 4.2 16.4 61.4 -9.2 259 1.3 8500 4.6 40.3 165 16 8 6.2 3.4 16.2 61.1 -9.5 237 1.2 8250 4.9 40.8 165 16 8 -0.9 -0.5 15.6 60.2 -10.0 223 1.1 8000 4.8 40.6 170 14 7 2.3 1.3 14.8 58.6 -10.9 218 1.1 7750 5.3 41.5 165 14 7 8.6 4.7 14.6 58.2 -11.1 195 1.0 7500 5.8 42.4 170 13 7 6.7 3.7 14.4 57.9 -11.3 171 0.9 7250 6.3 43.3 165 12 6 3.9 2.1 14.1 57.3 -11.7 151 0.8 7000 6.3 43.3 145 10 5 -1.9 -1.0 13.4 56.1 -12.4 143 0.7 6750 6.0 42.8 135 11 6 -4.5 -2.5 12.4 54.2 -13.4 143 0.7 6500 5.9 42.6 125 12 6 2.9 1.6 11.5 52.6 -14.4 141 0.7 6250 6.4 43.5 120 13 7 8.4 4.6 11.3 52.3 -14.6 117 0.6 6000 7.0 44.6 120 14 7 7.0 3.8 11.1 51.9 -14.8 93 0.5 5750 7.5 45.5 120 14 7 7.2 3.9 10.9 51.6 -15.0 69 0.4 5500 8.1 46.6 115 15 8 7.8 4.3 10.7 51.2 -15.3 45 0.2 5250 8.6 47.5 105 15 8 5.1 2.8 10.5 50.9 -15.5 22 0.1 5000 8.5 47.3 100 14 7 -9.6 -5.3 9.7 49.4 -16.3 17 0.1 * * * * * * Numerical weather prediction model forecast data valid * * * * * * 05/04/2024 at 0900 MDT | 05/04/2024 at 1200 MDT | CAPE... 0.0 LI... +4.4 | CAPE... +0.2 LI... +2.0 CINH... 0.0 K Index... +6.1 | CINH... -0.2 K Index... +14.0 | 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 -56.0 -68.8 250 33 17 1.2 0.7 | -56.1 -69.0 245 33 17 1.2 0.6 45000 -54.4 -65.9 255 38 20 -2.2 -1.2 | -54.6 -66.3 250 34 17 -2.3 -1.3 40000 -58.6 -73.5 255 38 19 -2.8 -1.6 | -58.8 -73.8 250 33 17 -2.8 -1.6 38000 -58.1 -72.6 255 35 18 4.3 2.4 | -58.1 -72.6 250 31 16 4.6 2.5 36000 -55.2 -67.4 250 30 15 4.3 2.4 | -55.0 -67.0 250 28 14 4.6 2.5 34000 -52.0 -61.6 250 26 13 7.4 4.1 | -51.7 -61.1 255 26 13 7.7 4.2 32000 -47.5 -53.5 245 24 12 7.5 4.1 | -47.0 -52.6 255 24 12 7.8 4.3 30000 -43.1 -45.6 245 22 11 7.3 4.0 | -42.5 -44.5 250 22 11 7.1 3.9 29000 -40.9 -41.6 240 21 11 7.3 4.0 | -40.3 -40.5 245 23 12 7.1 3.9 28000 -38.7 -37.7 240 20 10 7.3 4.0 | -38.2 -36.8 240 23 12 7.1 3.9 27000 -36.5 -33.7 240 19 10 7.8 4.3 | -36.1 -33.0 235 24 12 7.8 4.3 26000 -34.1 -29.4 235 18 9 7.9 4.3 | -33.7 -28.7 230 23 12 8.0 4.4 25000 -31.8 -25.2 235 18 9 7.9 4.3 | -31.3 -24.3 230 21 11 8.0 4.4 24000 -29.4 -20.9 230 17 9 8.1 4.4 | -28.9 -20.0 225 20 10 7.9 4.3 23000 -26.9 -16.4 230 16 8 8.4 4.6 | -26.6 -15.9 225 19 10 7.8 4.3 22000 -23.8 -10.8 230 14 7 8.4 4.6 | -23.7 -10.7 225 18 9 7.8 4.3 21000 -21.3 -6.3 230 14 7 7.9 4.4 | -21.4 -6.5 225 18 9 7.3 4.0 20000 -18.9 -2.0 235 14 7 8.0 4.4 | -19.3 -2.7 225 18 9 7.4 4.0 19500 -17.8 -0.0 240 14 7 8.0 4.4 | -18.2 -0.8 225 18 9 7.4 4.0 19000 -16.6 2.1 240 13 7 8.1 4.4 | -17.1 1.2 225 18 9 7.4 4.1 18500 -15.5 4.1 240 14 7 6.8 3.7 | -16.0 3.2 230 19 10 7.0 3.8 18000 -14.4 6.1 245 15 8 6.9 3.8 | -15.0 5.0 230 20 10 7.0 3.9 17500 -13.4 7.9 245 16 8 6.9 3.8 | -13.9 7.0 230 21 11 7.2 4.0 17000 -12.4 9.7 245 16 8 6.8 3.8 | -12.8 9.0 230 21 11 7.4 4.1 16500 -11.4 11.5 245 17 9 6.9 3.8 | -11.8 10.8 230 22 11 7.5 4.1 16000 -10.4 13.3 245 18 9 7.2 3.9 | -10.6 12.9 230 22 11 8.2 4.5 15500 -9.3 15.3 245 19 10 7.2 3.9 | -9.4 15.1 230 22 11 8.2 4.5 15000 -8.2 17.2 245 19 10 7.6 4.2 | -8.2 17.2 230 21 11 8.1 4.5 14500 -7.1 19.2 245 20 10 7.6 4.2 | -7.0 19.4 230 21 11 8.1 4.5 14000 -6.0 21.2 245 20 10 7.9 4.3 | -5.8 21.6 230 20 10 8.4 4.6 13500 -4.8 23.4 250 19 10 8.0 4.4 | -4.5 23.9 230 19 10 8.4 4.6 13000 -3.6 25.5 250 19 10 7.7 4.2 | -3.3 26.1 230 18 9 8.3 4.6 12500 -2.5 27.5 250 18 9 7.4 4.1 | -2.1 28.2 230 16 8 8.2 4.5 12000 -1.4 29.5 250 17 9 7.2 4.0 | -0.9 30.4 230 15 8 8.1 4.4 11500 -0.4 31.3 250 15 8 6.9 3.8 | 0.3 32.5 230 13 7 8.0 4.4 11000 0.7 33.3 250 14 7 6.2 3.4 | 1.5 34.7 230 12 6 7.2 4.0 10500 1.4 34.5 245 12 6 5.0 2.8 | 2.5 36.5 230 11 5 5.3 2.9 10250 1.8 35.2 240 11 6 6.5 3.6 | 3.0 37.4 230 10 5 9.7 5.3 10000 2.4 36.3 235 10 5 7.0 3.8 | 3.8 38.8 225 9 4 10.9 6.0 9750 2.8 37.0 230 9 5 5.6 3.1 | 4.4 39.9 225 8 4 6.7 3.7 9500 3.2 37.8 220 8 4 5.9 3.2 | 5.0 41.0 220 7 4 8.0 4.4 9250 3.6 38.5 215 8 4 5.9 3.2 | 5.5 41.9 215 6 3 5.4 3.0 9000 4.0 39.2 205 8 4 5.4 3.0 | 5.9 42.6 210 6 3 6.0 3.3 8750 4.4 39.9 200 7 4 5.0 2.7 | 6.5 43.7 205 5 3 8.7 4.8 8500 4.7 40.5 195 7 4 5.2 2.9 | 7.1 44.8 200 4 2 8.3 4.6 8250 5.1 41.2 185 7 3 4.6 2.5 | 7.7 45.9 195 4 2 7.2 3.9 8000 5.6 42.1 175 6 3 3.4 1.9 | 8.6 47.5 180 2 1 8.1 4.5 7750 5.9 42.6 170 5 3 4.3 2.3 | 9.3 48.7 175 2 1 10.3 5.6 7500 6.1 43.0 155 4 2 2.8 1.6 | 9.9 49.8 175 2 1 8.1 4.4 7250 6.2 43.2 145 4 2 0.8 0.4 | 10.4 50.7 165 1 1 6.1 3.3 7000 6.4 43.5 135 4 2 5.5 3.0 | 11.0 51.8 155 1 1 10.2 5.6 6750 7.0 44.6 110 3 1 8.8 4.8 | 11.9 53.4 160 1 1 13.1 7.2 6500 7.6 45.7 090 3 1 7.0 3.8 | 12.8 55.0 165 1 0 10.5 5.8 6250 8.1 46.6 085 3 2 6.3 3.5 | 13.5 56.3 150 1 0 9.9 5.4 6000 8.6 47.5 080 3 2 8.4 4.6 | 14.3 57.7 130 1 0 8.9 4.9 5750 9.5 49.1 075 3 1 16.9 9.2 | 15.0 59.0 165 1 0 15.0 8.2 5500 11.1 52.0 075 3 2 26.5 14.6 | 17.7 63.9 000 0 0 70.6 38.8 5250 M M M M M M M | M M M M M M M 5000 M M M M M M M | M M M M M M M 05/04/2024 at 1500 MDT | 05/04/2024 at 1800 MDT | CAPE... +17.8 LI... -0.2 | CAPE... +26.9 LI... -0.3 CINH... -9.4 K Index... +22.0 | CINH... -6.4 K Index... +19.8 | 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 -55.6 -68.1 250 34 18 0.9 0.5 | -55.9 -68.6 250 31 16 0.8 0.5 45000 -54.5 -66.1 250 36 18 -2.6 -1.4 | -54.8 -66.6 250 33 17 -2.7 -1.5 40000 -59.0 -74.2 240 32 17 -3.0 -1.7 | -59.6 -75.3 265 26 13 -3.2 -1.8 38000 -58.3 -72.9 240 30 15 4.7 2.6 | -58.2 -72.8 270 23 12 5.6 3.1 36000 -55.1 -67.2 245 26 13 4.7 2.6 | -54.8 -66.6 275 21 11 5.6 3.1 34000 -51.7 -61.1 250 23 12 8.0 4.4 | -51.1 -60.0 280 19 10 7.6 4.2 32000 -46.8 -52.2 250 22 11 8.0 4.4 | -46.5 -51.7 265 19 10 7.6 4.2 30000 -42.1 -43.8 250 21 11 7.6 4.2 | -41.8 -43.2 260 19 10 8.3 4.6 29000 -39.8 -39.6 245 21 11 7.6 4.1 | -39.3 -38.7 255 19 10 8.3 4.6 28000 -37.6 -35.7 240 21 11 7.6 4.1 | -36.8 -34.2 250 19 10 8.3 4.6 27000 -35.3 -31.5 240 22 11 7.6 4.2 | -34.4 -29.9 245 20 10 7.2 3.9 26000 -33.1 -27.6 235 22 12 7.6 4.2 | -32.4 -26.3 240 22 11 6.8 3.8 25000 -30.8 -23.4 230 24 12 7.6 4.2 | -30.3 -22.5 230 24 12 6.8 3.8 24000 -28.5 -19.3 225 25 13 7.5 4.1 | -28.3 -18.9 225 26 14 6.9 3.8 23000 -25.8 -14.4 220 24 12 7.4 4.0 | -25.7 -14.3 220 27 14 7.1 3.9 22000 -23.6 -10.5 215 23 12 7.4 4.0 | -23.5 -10.3 215 27 14 7.1 3.9 21000 -21.5 -6.7 210 23 12 7.0 3.9 | -21.4 -6.5 210 28 14 7.8 4.3 20000 -19.4 -2.9 210 23 12 7.1 3.9 | -19.1 -2.4 205 27 14 7.8 4.3 19500 -18.3 -0.9 210 23 12 7.1 3.9 | -17.9 -0.2 200 27 14 7.8 4.3 19000 -17.3 0.9 205 23 12 7.0 3.9 | -16.8 1.8 200 27 14 7.7 4.2 18500 -16.2 2.8 205 23 12 8.6 4.7 | -15.6 3.9 200 27 14 8.6 4.7 18000 -14.9 5.2 205 23 12 8.5 4.7 | -14.3 6.3 195 27 14 8.6 4.7 17500 -13.7 7.3 205 23 12 8.6 4.7 | -13.1 8.4 195 27 14 8.8 4.8 17000 -12.4 9.7 205 22 11 8.7 4.8 | -11.8 10.8 195 26 13 9.0 4.9 16500 -11.1 12.0 205 21 11 8.7 4.8 | -10.4 13.3 195 26 13 9.0 4.9 16000 -9.9 14.2 205 20 10 8.1 4.5 | -9.1 15.6 195 25 13 9.1 5.0 15500 -8.7 16.3 205 19 10 8.1 4.5 | -7.8 18.0 195 24 12 9.0 5.0 15000 -7.5 18.5 205 18 9 8.7 4.8 | -6.4 20.5 195 23 12 9.3 5.1 14500 -6.2 20.8 205 17 9 8.7 4.8 | -5.0 23.0 195 22 11 9.3 5.1 14000 -4.9 23.2 205 16 8 8.9 4.9 | -3.6 25.5 195 21 11 9.2 5.0 13500 -3.6 25.5 210 15 8 9.0 4.9 | -2.3 27.9 195 20 10 9.1 5.0 13000 -2.2 28.0 210 14 7 9.0 5.0 | -0.9 30.4 195 18 9 9.1 5.0 12500 -0.9 30.4 210 13 7 9.1 5.0 | 0.4 32.7 200 17 9 9.0 4.9 12000 0.5 32.9 210 12 6 9.0 5.0 | 1.7 35.1 200 16 8 8.9 4.9 11500 1.8 35.2 215 10 5 8.9 4.9 | 3.1 37.6 200 14 7 8.9 4.9 11000 3.2 37.8 220 9 5 8.2 4.5 | 4.4 39.9 200 13 7 8.5 4.7 10500 4.3 39.7 220 7 4 6.3 3.5 | 5.6 42.1 200 11 6 7.0 3.9 10250 4.8 40.6 225 7 3 10.7 5.8 | 6.1 43.0 200 10 5 9.8 5.4 10000 5.8 42.4 230 7 3 11.8 6.5 | 7.0 44.6 200 9 5 11.2 6.1 9750 6.5 43.7 235 6 3 7.7 4.2 | 7.7 45.9 205 9 4 8.7 4.8 9500 7.0 44.6 240 5 3 7.3 4.0 | 8.3 46.9 205 8 4 8.3 4.5 9250 7.6 45.7 245 4 2 10.0 5.5 | 9.0 48.2 205 7 3 9.2 5.1 9000 8.5 47.3 245 5 2 11.1 6.1 | 9.7 49.5 210 6 3 10.3 5.6 8750 9.2 48.6 250 5 2 8.9 4.9 | 10.5 50.9 215 6 3 9.4 5.1 8500 9.9 49.8 255 4 2 9.5 5.2 | 11.8 53.2 220 5 3 8.9 4.9 8250 11.2 52.2 275 4 2 8.7 4.7 | 12.5 54.5 225 5 3 9.1 5.0 8000 11.9 53.4 285 3 2 10.0 5.5 | 13.2 55.8 225 4 2 9.5 5.2 7750 12.7 54.9 280 4 2 11.1 6.1 | 13.9 57.0 230 4 2 9.8 5.4 7500 13.5 56.3 280 4 2 9.5 5.2 | 14.6 58.3 230 4 2 9.4 5.2 7250 14.1 57.4 290 4 2 7.3 4.0 | 15.3 59.5 235 4 2 8.4 4.6 7000 14.7 58.5 300 4 2 10.0 5.5 | 15.9 60.6 240 3 2 9.4 5.2 6750 15.6 60.1 290 4 2 12.4 6.8 | 16.7 62.1 240 4 2 10.6 5.8 6500 16.5 61.7 285 4 2 10.8 5.9 | 17.5 63.5 240 4 2 10.4 5.7 6250 17.2 63.0 300 4 2 10.4 5.7 | 18.3 64.9 245 3 2 11.2 6.1 6000 18.0 64.4 310 4 2 8.8 4.8 | 19.1 66.4 255 3 2 8.8 4.8 5750 18.7 65.7 295 4 2 14.6 8.0 | 19.7 67.5 250 3 2 9.8 5.4 5500 21.5 70.7 315 4 2 77.0 42.2 | 21.5 70.7 270 2 1 49.3 27.0 5250 M M M M M M M | M M M M M M M 5000 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) 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 at Walker Field in Grand Junction, Colorado at North Latitude: 39 deg 07 min 00.001 sec West Longitude: 108 deg 31 min 59.998 sec Elevation: 4839 feet (1475 meters) and may not be representative of other areas along the Western Slope of Colorado. 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