


Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
119 UXUS97 KPUB 021215 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0614 MDT Saturday, August 2, 2025 This forecast is for Villa Grove, CO for Saturday, August 2, 2025: If the trigger temperature of 68.0 F/20.0 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 1346 ft/min (6.8 m/s) Maximum height of thermals.................. 22393 ft MSL (13409 ft AGL) Forecast maximum temperature................... 79.0 F/26.6 C Time of trigger temperature.................... 0945 MDT Time of overdevelopment........................ 1400 MDT Middle/high clouds during soaring window....... None Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 19934 ft MSL (10951 ft AGL) Thermal soaring outlook for Sunday 08/03....... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 06:07:28 / 20:12:11 MDT Total possible sunshine........... 14 hr 4 min 44 sec (844 min 44 sec) Altitude of sun at 13:09:49 MDT... 69.16 degrees Upper air data from numerical model forecast valid on 08/02/2025 at 0600 MDT Freezing level.................. 15893 ft MSL (6909 ft AGL) Convective condensation level... 17013 ft MSL (8029 ft AGL) Lifted condensation level....... 19127 ft MSL (10144 ft AGL) Lifted index.................... -4.1 K index......................... +15.9 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 -62.5 -80.5 275 27 14 2.7 1.5 M M M M M 45000 -57.3 -71.1 275 48 25 5.1 2.8 M M M M M 40000 -49.4 -56.9 275 54 28 4.2 2.3 M M M M M 38000 -46.9 -52.4 280 57 29 4.2 2.3 M M M M M 36000 -44.4 -47.9 285 60 31 5.3 2.9 M M M M M 34000 -39.7 -39.5 285 58 30 8.1 4.4 M M M M M 32000 -34.8 -30.6 285 56 29 8.4 4.6 M M M M M 30000 -30.4 -22.7 280 53 27 7.4 4.1 34.5 94.0 6.6 M M 29000 -27.6 -17.7 280 51 26 7.4 4.0 33.4 92.2 5.9 M M 28000 -25.6 -14.1 280 48 25 5.5 3.0 32.4 90.3 5.1 M M 27000 -23.9 -11.0 280 44 23 5.7 3.1 30.8 87.4 3.8 M M 26000 -22.2 -8.0 285 40 21 5.7 3.1 29.3 84.8 2.7 M M 25000 -20.4 -4.7 285 36 19 7.1 3.9 28.1 82.5 1.6 M M 24000 -18.1 -0.6 285 33 17 7.7 4.2 27.2 81.0 0.9 M M 23000 -15.8 3.6 285 29 15 7.7 4.2 26.5 79.8 0.3 M M 22000 -13.6 7.5 285 26 13 6.1 3.3 25.8 78.4 -0.3 1310 6.7 21000 -11.9 10.6 285 23 12 5.8 3.2 24.4 75.9 -1.6 1230 6.2 20000 -10.2 13.6 285 20 10 6.0 3.3 23.1 73.6 -2.9 1150 5.8 19500 -9.4 15.1 285 18 9 6.9 3.8 22.5 72.5 -3.5 1110 5.6 19000 -8.2 17.2 285 18 9 8.5 4.7 22.2 72.0 -3.8 1059 5.4 18500 -7.0 19.4 285 17 9 8.5 4.7 22.0 71.7 -4.0 1007 5.1 18000 -5.7 21.7 290 17 9 8.5 4.7 21.8 71.3 -4.2 955 4.9 17500 -4.5 23.9 290 16 8 8.5 4.7 21.6 70.9 -4.5 903 4.6 17000 -3.2 26.2 290 16 8 8.8 4.8 21.4 70.6 -4.7 852 4.3 16500 -1.9 28.6 290 16 8 9.2 5.0 21.3 70.4 -4.9 797 4.0 16000 -0.6 30.9 290 16 8 9.2 5.1 21.2 70.2 -5.0 742 3.8 15500 0.7 33.3 290 16 8 8.9 4.9 21.1 70.0 -5.2 688 3.5 15000 2.7 36.9 290 16 8 8.9 4.9 20.9 69.7 -5.5 607 3.1 14500 4.0 39.2 290 16 8 9.2 5.1 20.8 69.5 -5.7 553 2.8 14000 5.4 41.7 290 16 8 9.4 5.1 20.8 69.4 -5.8 497 2.5 13500 6.9 44.4 290 16 8 10.9 6.0 20.8 69.5 -5.8 438 2.2 13000 8.2 46.8 290 16 8 7.5 4.1 20.7 69.3 -5.9 383 1.9 12500 9.4 48.9 285 16 8 9.0 4.9 20.5 68.9 -6.2 332 1.7 12000 10.7 51.3 280 15 8 8.9 4.9 20.4 68.7 -6.4 279 1.4 11750 11.3 52.3 280 15 8 7.7 4.2 20.3 68.6 -6.5 253 1.3 11500 11.8 53.2 275 14 7 6.4 3.5 20.1 68.2 -6.8 231 1.2 11250 12.2 54.0 270 14 7 5.8 3.2 19.8 67.6 -7.2 212 1.1 11000 12.6 54.7 270 13 7 6.4 3.5 19.5 67.1 -7.5 192 1.0 10750 13.0 55.4 265 13 7 4.8 2.6 19.2 66.6 -7.8 172 0.9 10500 13.1 55.6 260 13 6 0.2 0.1 18.7 65.6 -8.4 161 0.8 10250 13.0 55.4 255 12 6 -2.3 -1.2 17.8 64.1 -9.4 159 0.8 10000 12.8 55.0 250 12 6 0.3 0.1 17.0 62.6 -10.3 156 0.8 9750 12.6 54.7 245 12 6 -7.2 -3.9 16.2 61.1 -11.2 154 0.8 9500 11.5 52.7 240 11 6 -20.7 -11.4 14.3 57.7 -13.1 181 0.9 9250 9.9 49.8 235 8 4 -21.3 -11.7 11.9 53.4 -15.5 223 1.1 9000 8.2 46.8 235 6 3 -26.8 -14.7 9.5 49.1 -17.9 265 1.3 8750 M M M M M M M M M M M M 8500 M M M M M M M M M M M M 8250 M M M M M M M M M M M M 8000 M M M M M M M M M M M M * * * * * * Numerical weather prediction model forecast data valid * * * * * * 08/02/2025 at 0900 MDT | 08/02/2025 at 1200 MDT | CAPE... +447.2 LI... -2.4 | CAPE... +742.0 LI... -3.4 CINH... -81.8 K Index... +16.6 | CINH... -0.2 K Index... +23.2 | 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 -63.4 -82.1 275 28 14 3.0 1.6 | -62.9 -81.2 265 32 16 2.5 1.4 45000 -57.6 -71.7 275 49 25 5.5 3.0 | -57.6 -71.7 265 54 28 5.6 3.1 40000 -49.4 -56.9 275 60 31 4.0 2.2 | -49.2 -56.6 270 65 34 4.2 2.3 38000 -47.0 -52.6 280 60 31 4.0 2.2 | -46.6 -51.9 275 63 33 4.2 2.3 36000 -44.6 -48.3 280 60 31 5.2 2.8 | -44.1 -47.4 280 62 32 4.9 2.7 34000 -40.1 -40.2 280 57 29 7.6 4.2 | -40.1 -40.2 275 58 30 6.8 3.7 32000 -35.5 -31.9 280 54 28 7.8 4.3 | -36.0 -32.8 275 55 28 6.9 3.8 30000 -30.8 -23.4 280 51 26 7.9 4.3 | -31.4 -24.5 275 51 26 7.9 4.3 29000 -27.9 -18.2 280 49 25 7.9 4.3 | -28.4 -19.1 275 49 25 7.9 4.3 28000 -25.7 -14.3 280 48 24 6.1 3.3 | -26.2 -15.2 275 47 24 6.4 3.5 27000 -23.9 -11.0 280 45 23 6.2 3.4 | -24.3 -11.7 280 45 23 6.5 3.6 26000 -22.0 -7.6 280 42 22 6.2 3.4 | -22.3 -8.1 280 43 22 6.5 3.6 25000 -20.2 -4.4 280 39 20 6.7 3.7 | -20.3 -4.5 280 40 21 7.2 4.0 24000 -18.1 -0.6 285 33 17 6.9 3.8 | -18.1 -0.6 280 34 18 7.4 4.1 23000 -16.1 3.0 285 28 14 7.0 3.8 | -15.9 3.4 280 28 14 7.4 4.1 22000 -14.0 6.8 290 22 12 6.6 3.6 | -13.8 7.2 280 23 12 6.6 3.6 21000 -12.1 10.2 290 21 11 6.6 3.6 | -11.8 10.8 280 22 12 6.6 3.6 20000 -10.2 13.6 285 19 10 6.7 3.7 | -9.9 14.2 275 22 11 6.8 3.7 19500 -9.2 15.4 285 19 10 7.1 3.9 | -8.9 16.0 275 22 11 7.3 4.0 19000 -8.1 17.4 285 18 9 7.6 4.2 | -7.8 18.0 275 21 11 8.1 4.5 18500 -7.0 19.4 290 17 9 7.6 4.2 | -6.7 19.9 275 20 10 8.3 4.6 18000 -5.8 21.6 290 17 9 8.1 4.4 | -5.5 22.1 275 19 10 8.6 4.7 17500 -4.7 23.5 290 16 8 8.1 4.5 | -4.3 24.3 275 18 9 8.6 4.7 17000 -3.5 25.7 290 16 8 8.4 4.6 | -3.1 26.4 275 17 9 8.9 4.9 16500 -2.3 27.9 290 16 8 8.6 4.7 | -1.8 28.8 275 16 8 9.1 5.0 16000 -1.0 30.2 290 16 8 8.7 4.8 | -0.5 31.1 275 15 8 9.2 5.0 15500 0.3 32.5 290 16 8 9.7 5.3 | 0.9 33.6 270 15 8 9.6 5.3 15000 2.4 36.3 285 16 8 9.3 5.1 | 3.0 37.4 270 14 7 9.1 5.0 14500 3.7 38.7 285 17 9 9.5 5.2 | 4.3 39.7 270 14 7 9.8 5.4 14000 5.1 41.2 285 17 9 10.2 5.6 | 5.8 42.4 265 13 7 10.3 5.6 13500 6.6 43.9 285 17 9 10.0 5.5 | 7.3 45.1 265 13 7 9.9 5.4 13000 8.0 46.4 280 17 9 9.0 4.9 | 8.7 47.7 265 12 6 9.3 5.1 12500 9.4 48.9 280 17 9 9.4 5.1 | 10.1 50.2 260 12 6 10.4 5.7 12000 10.7 51.3 280 17 9 9.0 4.9 | 11.6 52.9 260 12 6 9.9 5.4 11750 11.3 52.3 275 16 8 7.3 4.0 | 12.4 54.3 260 12 6 9.5 5.2 11500 11.8 53.2 275 16 8 5.9 3.3 | 13.1 55.6 255 11 6 9.6 5.3 11250 12.2 54.0 270 16 8 5.6 3.1 | 13.8 56.8 255 11 6 9.6 5.3 11000 12.6 54.7 270 15 8 5.9 3.2 | 14.5 58.1 255 11 6 9.6 5.3 10750 13.0 55.4 265 15 8 5.9 3.2 | 15.2 59.4 255 11 6 10.8 5.9 10500 13.3 55.9 260 14 7 2.2 1.2 | 16.0 60.8 255 11 5 10.7 5.9 10250 13.2 55.8 255 13 7 0.2 0.1 | 16.8 62.2 255 10 5 10.1 5.6 10000 13.2 55.8 250 13 7 -0.2 -0.1 | 17.6 63.7 250 10 5 9.4 5.2 9750 13.1 55.6 240 12 6 3.8 2.1 | 18.3 64.9 250 10 5 12.9 7.1 9500 13.8 56.8 240 11 6 13.1 7.2 | 19.6 67.3 250 10 5 20.9 11.5 9250 14.9 58.8 235 9 5 16.2 8.9 | 21.2 70.2 250 9 5 23.5 12.9 9000 16.0 60.8 225 8 4 14.5 7.9 | 22.9 73.2 245 9 4 22.1 12.1 8750 M M M M M M M | M M M M M M M 8500 M M M M M M M | M M M M M M M 8250 M M M M M M M | M M M M M M M 8000 M M M M M M M | M M M M M M M 08/02/2025 at 1500 MDT | 08/02/2025 at 1800 MDT | CAPE... +819.4 LI... -2.8 | CAPE... +522.8 LI... -1.6 CINH... -14.1 K Index... +30.0 | CINH... -14.5 K Index... +26.8 | 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 -62.6 -80.7 270 33 17 2.9 1.6 | -61.7 -79.1 275 30 16 4.0 2.2 45000 -57.2 -71.0 270 55 28 4.9 2.7 | -55.7 -68.3 280 54 28 3.9 2.2 40000 -49.6 -57.3 275 66 34 4.5 2.5 | -49.5 -57.1 280 70 36 4.1 2.2 38000 -46.9 -52.4 275 67 34 4.5 2.5 | -47.1 -52.8 280 70 36 4.1 2.2 36000 -44.2 -47.6 280 68 35 5.1 2.8 | -44.6 -48.3 280 70 36 4.5 2.5 34000 -40.3 -40.5 275 64 33 6.7 3.7 | -40.9 -41.6 280 66 34 6.4 3.5 32000 -36.3 -33.3 270 60 31 6.7 3.7 | -37.1 -34.8 275 61 31 6.3 3.4 30000 -31.9 -25.4 270 55 28 7.5 4.1 | -32.7 -26.9 270 54 28 7.4 4.1 29000 -29.6 -21.3 270 52 27 7.5 4.1 | -30.5 -22.9 270 50 26 7.5 4.1 28000 -26.9 -16.4 270 48 25 7.4 4.1 | -27.7 -17.9 265 44 23 8.2 4.5 27000 -24.7 -12.5 270 44 23 7.4 4.1 | -25.3 -13.5 265 38 20 8.2 4.5 26000 -22.5 -8.5 270 41 21 7.5 4.1 | -22.9 -9.2 260 32 17 8.2 4.5 25000 -20.3 -4.5 270 37 19 7.7 4.2 | -20.5 -4.9 255 27 14 7.8 4.3 24000 -18.0 -0.4 270 33 17 7.8 4.3 | -18.3 -0.9 260 27 14 7.7 4.2 23000 -15.7 3.7 270 29 15 7.8 4.3 | -16.0 3.2 260 28 14 7.7 4.2 22000 -13.5 7.7 270 25 13 7.6 4.2 | -13.8 7.2 265 28 14 7.8 4.3 21000 -11.3 11.7 275 22 11 7.7 4.2 | -11.5 11.3 270 27 14 7.8 4.3 20000 -9.1 15.6 280 19 10 7.7 4.2 | -9.2 15.4 270 27 14 7.8 4.3 19500 -7.9 17.8 285 18 9 7.9 4.3 | -8.1 17.4 275 26 14 7.8 4.3 19000 -6.8 19.8 285 17 9 8.0 4.4 | -6.9 19.6 275 26 13 7.9 4.4 18500 -5.6 21.9 285 16 8 8.0 4.4 | -5.7 21.7 275 25 13 7.9 4.3 18000 -4.4 24.1 280 15 8 8.2 4.5 | -4.5 23.9 280 24 12 8.9 4.9 17500 -3.2 26.2 280 14 7 8.2 4.5 | -3.2 26.2 280 23 12 9.0 4.9 17000 -2.0 28.4 275 14 7 8.5 4.7 | -1.9 28.6 280 22 11 9.1 5.0 16500 -0.7 30.7 275 13 7 8.9 4.9 | -0.5 31.1 275 21 11 9.4 5.1 16000 0.6 33.1 275 13 7 8.9 4.9 | 0.9 33.6 275 21 11 9.4 5.2 15500 1.9 35.4 270 13 7 9.0 5.0 | 2.3 36.1 275 20 11 9.1 5.0 15000 3.2 37.8 265 13 7 9.1 5.0 | 4.3 39.7 275 20 10 9.1 5.0 14500 4.5 40.1 260 13 7 8.2 4.5 | 5.6 42.1 270 20 10 9.3 5.1 14000 5.8 42.4 255 13 7 9.4 5.2 | 7.0 44.6 270 20 10 9.2 5.1 13500 7.2 45.0 250 14 7 8.8 4.8 | 8.5 47.3 270 20 10 10.5 5.8 13000 9.1 48.4 245 15 8 8.5 4.7 | 9.8 49.6 265 20 10 8.0 4.4 12500 10.3 50.5 240 16 8 7.9 4.3 | 11.1 52.0 260 20 10 9.6 5.3 12000 11.4 52.5 235 17 9 8.0 4.4 | 12.5 54.5 260 20 10 8.9 4.9 11750 12.0 53.6 235 18 9 8.3 4.5 | 13.1 55.6 255 19 10 8.2 4.5 11500 12.6 54.7 230 18 9 8.4 4.6 | 13.8 56.8 255 19 10 8.8 4.8 11250 13.2 55.8 230 18 9 8.5 4.6 | 14.4 57.9 255 19 10 9.0 4.9 11000 13.8 56.8 230 18 9 8.4 4.6 | 15.1 59.2 250 18 9 8.9 4.9 10750 14.5 58.1 230 18 9 11.4 6.2 | 15.8 60.4 250 18 9 10.2 5.6 10500 15.4 59.7 230 18 9 11.3 6.2 | 16.5 61.7 245 18 9 10.5 5.7 10250 16.1 61.0 230 18 9 9.3 5.1 | 17.2 63.0 245 18 9 9.5 5.2 10000 16.8 62.2 225 18 9 9.2 5.0 | 18.0 64.4 245 17 9 10.0 5.5 9750 17.5 63.5 225 18 9 11.9 6.5 | 18.7 65.7 240 16 8 9.1 5.0 9500 18.6 65.5 225 17 9 17.8 9.8 | 19.3 66.7 240 16 8 10.5 5.7 9250 20.0 68.0 225 15 8 18.8 10.3 | 20.3 68.5 240 13 7 15.3 8.4 9000 21.4 70.5 230 14 7 19.6 10.8 | 21.2 70.2 235 11 6 6.1 3.3 8750 M M M M M M M | M M M M M M M 8500 M M M M M M M | M M M M M M M 8250 M M M M M M M | M M M M M M M 8000 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 Villa Grove, Colorado at: North Latitude: 38 deg 16 min 03 sec West Longitude: 105 deg 53 min 37 sec Elevation: 7986 feet (2434 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