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Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
621 UXUS97 KPUB 131212 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0612 MDT Tuesday, August 13, 2024 This forecast is for Villa Grove, CO for Tuesday, August 13, 2024: If the trigger temperature of 65.4 F/18.6 C is reached...then Thermal Soaring Index....................... Good Maximum rate of lift........................ 488 ft/min (2.5 m/s) Maximum height of thermals.................. 16461 ft MSL (7513 ft AGL) Forecast maximum temperature................... 73.0 F/23.2 C Time of trigger temperature.................... 1030 MDT Time of overdevelopment........................ None Middle/high clouds during soaring window....... Broken/overcast thin middle Surface winds during soaring window............ 20 mph or less Height of the -3 thermal index................. 14286 ft MSL (5338 ft AGL) Thermal soaring outlook for Wednesday 08/14.... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 06:17:19 / 19:59:18 MDT Total possible sunshine........... 13 hr 41 min 59 sec (821 min 59 sec) Altitude of sun at 13:08:19 MDT... 66.00 degrees Upper air data from numerical model forecast valid on 08/13/2024 at 0600 MDT Freezing level.................. 16598 ft MSL (7650 ft AGL) Convective condensation level... 14392 ft MSL (5444 ft AGL) Lifted condensation level....... 15657 ft MSL (6709 ft AGL) Lifted index.................... -3.4 K index......................... +15.5 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 -64.9 -84.8 235 19 10 1.4 0.8 M M M M M 45000 -60.2 -76.4 230 28 14 6.0 3.3 M M M M M 40000 -50.7 -59.3 215 33 17 7.9 4.3 M M M M M 38000 -45.9 -50.6 210 31 16 7.9 4.3 M M M M M 36000 -41.2 -42.2 200 30 15 7.7 4.2 M M M M M 34000 -36.8 -34.2 200 25 13 7.3 4.0 M M M M M 32000 -31.9 -25.4 205 20 10 8.1 4.4 M M M M M 30000 -27.5 -17.5 215 17 9 7.4 4.0 36.8 98.2 11.0 M M 29000 -25.4 -13.7 225 16 8 7.4 4.1 36.0 96.8 10.5 M M 28000 -23.1 -9.6 230 16 8 8.2 4.5 35.3 95.5 10.0 M M 27000 -20.7 -5.3 235 16 8 8.1 4.5 34.6 94.2 9.5 M M 26000 -18.2 -0.8 235 16 8 8.1 4.5 34.0 93.2 9.1 M M 25000 -15.8 3.6 235 16 8 7.7 4.2 33.5 92.3 8.9 M M 24000 -13.6 7.5 230 16 8 7.3 4.0 32.5 90.6 8.1 M M 23000 -11.4 11.5 225 16 8 7.3 4.0 31.7 89.0 7.5 M M 22000 -9.2 15.4 225 17 9 6.3 3.5 30.9 87.6 6.9 M M 21000 -7.6 18.3 225 17 9 5.4 3.0 29.3 84.8 5.6 M M 20000 -6.0 21.2 230 17 9 5.4 3.0 27.9 82.2 4.3 M M 19500 -5.2 22.6 230 17 9 5.4 3.0 27.2 80.9 3.7 M M 19000 -4.3 24.3 235 17 9 6.7 3.7 26.6 79.8 3.1 M M 18500 -3.4 25.9 240 17 9 6.6 3.6 26.0 78.9 2.6 M M 18000 -2.5 27.5 245 18 9 6.4 3.5 25.6 78.0 2.1 M M 17500 -1.6 29.1 250 20 10 6.2 3.4 24.9 76.9 1.5 M M 17000 -0.8 30.6 255 21 11 6.3 3.5 24.4 75.9 0.9 M M 16500 0.0 32.0 255 22 12 5.5 3.0 23.7 74.7 0.2 M M 16000 0.8 33.4 255 24 12 5.7 3.1 23.1 73.5 -0.5 660 3.4 15500 1.5 34.7 255 25 13 5.4 3.0 22.4 72.3 -1.2 623 3.2 15000 2.3 36.1 250 26 14 5.3 2.9 21.7 71.0 -2.0 586 3.0 14500 3.0 37.4 250 28 14 6.1 3.3 21.0 69.8 -2.7 549 2.8 14000 4.5 40.1 250 27 14 7.3 4.0 20.4 68.7 -3.4 481 2.4 13500 5.6 42.1 250 27 14 8.1 4.4 20.0 68.1 -3.8 434 2.2 13000 6.8 44.2 250 24 13 8.5 4.7 19.8 67.7 -4.1 383 1.9 12500 8.0 46.4 250 22 11 8.1 4.5 19.7 67.4 -4.3 331 1.7 12000 9.1 48.4 255 20 10 8.1 4.4 19.3 66.8 -4.7 284 1.4 11750 9.7 49.5 255 18 9 9.2 5.0 19.2 66.6 -4.8 258 1.3 11500 10.4 50.7 260 17 9 7.6 4.2 19.2 66.5 -5.0 232 1.2 11250 10.8 51.4 260 16 8 6.0 3.3 18.9 66.0 -5.3 211 1.1 11000 11.2 52.2 265 16 8 5.6 3.0 18.6 65.5 -5.6 191 1.0 10750 11.7 53.1 265 15 8 7.9 4.3 18.3 65.0 -5.9 171 0.9 10500 12.2 54.0 270 15 8 4.5 2.5 18.2 64.8 -6.1 147 0.7 10250 12.2 54.0 270 15 7 -2.0 -1.1 17.5 63.4 -6.9 140 0.7 10000 12.0 53.6 265 14 7 -1.2 -0.6 16.6 61.8 -7.8 138 0.7 9750 11.8 53.2 265 13 7 -3.7 -2.0 15.7 60.3 -8.7 136 0.7 9500 11.4 52.5 265 12 6 -3.9 -2.1 14.6 58.3 -9.9 143 0.7 9250 11.3 52.3 255 9 5 3.5 1.9 13.9 56.9 -10.7 137 0.7 9000 11.4 52.5 245 6 3 -7.6 -4.2 13.2 55.8 -11.4 128 0.7 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 * * * * * * 08/13/2024 at 0900 MDT | 08/13/2024 at 1200 MDT | CAPE... +582.5 LI... -2.4 | CAPE... +969.4 LI... -3.4 CINH... -27.9 K Index... +19.5 | CINH... -0.1 K Index... +21.9 | 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 -64.4 -83.9 240 18 9 1.6 0.9 | -64.0 -83.2 230 16 8 0.9 0.5 45000 -59.7 -75.5 225 24 12 5.8 3.2 | -59.9 -75.8 215 24 13 6.0 3.3 40000 -50.5 -58.9 210 29 15 8.0 4.4 | -49.9 -57.8 205 29 15 7.7 4.2 38000 -45.7 -50.3 210 29 15 8.0 4.4 | -45.3 -49.5 210 27 14 7.7 4.2 36000 -40.9 -41.6 210 29 15 7.7 4.2 | -40.7 -41.3 215 26 13 7.4 4.1 34000 -36.3 -33.3 205 27 14 6.8 3.7 | -36.4 -33.5 220 24 12 7.2 3.9 32000 -32.2 -26.0 200 25 13 7.1 3.9 | -32.1 -25.8 220 23 12 7.5 4.1 30000 -28.2 -18.8 200 21 11 6.9 3.8 | -28.1 -18.6 225 20 10 6.6 3.6 29000 -26.2 -15.2 205 19 10 6.9 3.8 | -26.2 -15.2 225 19 10 6.7 3.7 28000 -24.0 -11.2 205 18 9 8.4 4.6 | -24.1 -11.4 225 17 9 7.7 4.2 27000 -21.6 -6.9 200 17 9 8.2 4.5 | -21.2 -6.2 220 17 9 8.0 4.4 26000 -19.2 -2.6 200 16 8 8.2 4.5 | -18.9 -2.0 215 17 9 8.0 4.4 25000 -16.7 1.9 200 16 8 7.5 4.1 | -16.6 2.1 210 17 9 6.4 3.5 24000 -14.7 5.5 200 16 8 6.6 3.6 | -14.9 5.2 210 19 10 5.6 3.1 23000 -12.8 9.0 205 16 8 6.6 3.6 | -13.3 8.1 215 21 11 5.7 3.1 22000 -10.8 12.6 210 16 8 6.2 3.4 | -11.6 11.1 215 22 12 6.9 3.8 21000 -9.1 15.6 215 15 8 5.8 3.2 | -9.4 15.1 220 21 11 7.4 4.0 20000 -7.4 18.7 220 15 8 5.8 3.2 | -7.2 19.0 225 21 11 7.4 4.1 19500 -6.5 20.3 225 14 7 5.8 3.2 | -6.1 21.0 225 20 11 7.5 4.1 19000 -5.5 22.1 225 15 8 7.6 4.2 | -5.0 23.0 230 20 10 7.8 4.3 18500 -4.5 23.9 230 17 9 7.5 4.1 | -3.9 25.0 230 20 10 7.9 4.3 18000 -3.4 25.9 230 19 10 7.3 4.0 | -2.8 27.0 230 19 10 7.4 4.0 17500 -2.4 27.7 235 19 10 7.2 3.9 | -1.8 28.8 235 19 10 7.2 3.9 17000 -1.3 29.7 235 20 10 7.2 3.9 | -0.8 30.6 235 20 10 7.1 3.9 16500 -0.3 31.5 240 20 11 6.9 3.8 | 0.2 32.4 235 20 10 6.2 3.4 16000 1.1 34.0 240 20 10 7.0 3.8 | 1.1 34.0 240 20 11 6.3 3.4 15500 2.0 35.6 245 20 10 6.4 3.5 | 2.1 35.8 240 21 11 6.5 3.6 15000 3.0 37.4 250 20 10 6.4 3.5 | 3.0 37.4 240 21 11 6.5 3.6 14500 3.9 39.0 250 20 10 6.9 3.8 | 4.0 39.2 240 21 11 5.7 3.1 14000 4.9 40.8 255 21 11 6.4 3.5 | 4.8 40.6 240 21 11 7.3 4.0 13500 5.8 42.4 255 21 11 8.3 4.5 | 6.3 43.3 240 20 10 7.9 4.3 13000 6.9 44.4 250 22 11 7.1 3.9 | 7.4 45.3 240 19 10 7.1 3.9 12500 8.0 46.4 250 21 11 7.5 4.1 | 8.3 46.9 235 17 9 8.0 4.4 12000 9.1 48.4 245 20 10 7.0 3.9 | 9.5 49.1 230 15 8 8.6 4.7 11750 9.5 49.1 240 18 9 6.3 3.5 | 10.0 50.0 230 15 8 8.8 4.8 11500 10.0 50.0 240 17 9 5.9 3.2 | 10.6 51.1 225 14 7 9.0 4.9 11250 10.3 50.5 240 16 8 5.2 2.9 | 11.3 52.3 225 14 7 9.2 5.0 11000 10.7 51.3 240 14 7 5.1 2.8 | 12.0 53.6 225 14 7 8.9 4.9 10750 11.0 51.8 240 13 7 6.1 3.4 | 12.7 54.9 225 13 7 11.3 6.2 10500 11.5 52.7 240 12 6 5.9 3.2 | 13.6 56.5 225 13 7 12.1 6.6 10250 11.8 53.2 240 11 6 4.4 2.4 | 14.4 57.9 225 13 7 10.4 5.7 10000 12.1 53.8 240 11 5 4.7 2.6 | 15.2 59.4 220 13 7 11.4 6.2 9750 12.4 54.3 235 10 5 4.2 2.3 | 16.0 60.8 220 12 6 9.0 4.9 9500 12.7 54.9 235 9 5 10.3 5.7 | 16.7 62.1 220 12 6 16.0 8.8 9250 13.9 57.0 230 8 4 21.6 11.8 | 18.6 65.5 220 11 6 34.1 18.7 9000 15.1 59.2 225 7 4 1.9 1.1 | 20.4 68.7 220 10 5 0.9 0.5 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 08/13/2024 at 1500 MDT | 08/13/2024 at 1800 MDT | CAPE... +774.3 LI... -3.1 | CAPE... +751.4 LI... -2.8 CINH... -0.1 K Index... +27.2 | CINH... -1.0 K Index... +29.6 | 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 -83.7 220 15 8 1.3 0.7 | -63.5 -82.3 230 19 10 1.6 0.9 45000 -59.9 -75.8 210 24 12 6.0 3.3 | -59.1 -74.4 220 28 14 5.4 2.9 40000 -50.1 -58.2 215 30 16 7.4 4.0 | -50.3 -58.5 215 32 16 6.8 3.7 38000 -45.7 -50.3 225 29 15 7.4 4.0 | -46.2 -51.2 220 34 17 6.8 3.7 36000 -41.2 -42.2 230 27 14 7.7 4.2 | -42.2 -44.0 220 36 18 7.9 4.3 34000 -36.5 -33.7 235 25 13 7.9 4.3 | -37.0 -34.6 225 33 17 8.6 4.7 32000 -31.8 -25.2 245 24 12 8.4 4.6 | -31.8 -25.2 225 31 16 9.2 5.1 30000 -27.5 -17.5 240 22 11 7.2 3.9 | -27.1 -16.8 225 27 14 7.8 4.3 29000 -25.3 -13.5 240 21 11 7.2 3.9 | -24.8 -12.6 225 25 13 7.8 4.3 28000 -22.6 -8.7 240 20 10 7.5 4.1 | -22.0 -7.6 225 23 12 6.9 3.8 27000 -20.4 -4.7 235 20 10 7.5 4.1 | -20.0 -4.0 225 24 12 7.0 3.8 26000 -18.2 -0.8 230 21 11 7.6 4.2 | -18.0 -0.4 230 24 12 7.0 3.9 25000 -16.0 3.2 225 22 11 6.4 3.5 | -15.9 3.4 230 24 12 6.8 3.7 24000 -14.3 6.3 220 22 12 5.8 3.2 | -14.0 6.8 230 23 12 6.6 3.6 23000 -12.7 9.1 220 23 12 5.9 3.2 | -12.1 10.2 230 22 11 6.7 3.6 22000 -11.0 12.2 215 24 12 6.2 3.4 | -10.2 13.6 230 21 11 6.3 3.4 21000 -9.1 15.6 215 25 13 6.4 3.5 | -8.4 16.9 230 20 10 6.1 3.3 20000 -7.3 18.9 215 25 13 6.4 3.5 | -6.7 19.9 230 18 9 6.1 3.3 19500 -6.3 20.7 215 25 13 6.4 3.5 | -5.8 21.6 230 17 9 6.1 3.3 19000 -5.3 22.5 215 25 13 6.9 3.8 | -5.0 23.0 225 16 8 5.9 3.3 18500 -4.3 24.3 215 24 12 6.9 3.8 | -4.1 24.6 225 14 7 5.9 3.3 18000 -3.3 26.1 220 23 12 7.0 3.8 | -3.2 26.2 225 13 7 6.2 3.4 17500 -2.3 27.9 220 22 12 7.0 3.9 | -2.3 27.9 225 11 6 6.4 3.5 17000 -1.3 29.7 225 21 11 7.1 3.9 | -1.4 29.5 220 10 5 6.5 3.5 16500 -0.2 31.6 230 21 11 7.4 4.1 | -0.5 31.1 220 10 5 6.6 3.6 16000 0.8 33.4 230 20 11 7.4 4.1 | 0.4 32.7 220 10 5 6.6 3.6 15500 1.9 35.4 235 20 10 7.9 4.3 | 1.4 34.5 225 10 5 7.8 4.3 15000 3.0 37.4 235 19 10 7.9 4.4 | 2.6 36.7 230 9 5 8.1 4.4 14500 4.1 39.4 230 18 9 7.5 4.1 | 3.7 38.7 230 9 5 8.2 4.5 14000 5.2 41.4 230 18 9 9.3 5.1 | 5.0 41.0 235 9 5 9.7 5.3 13500 7.1 44.8 225 17 9 8.6 4.7 | 6.4 43.5 240 9 5 9.3 5.1 13000 8.5 47.3 225 17 9 10.5 5.8 | 8.4 47.1 250 10 5 9.8 5.4 12500 10.0 50.0 225 17 9 9.6 5.3 | 9.8 49.6 260 10 5 9.2 5.1 12000 11.4 52.5 225 17 9 10.0 5.5 | 11.2 52.2 260 11 5 9.9 5.4 11750 12.2 54.0 225 17 9 10.8 5.9 | 11.9 53.4 260 11 5 10.9 6.0 11500 13.0 55.4 225 17 9 10.1 5.5 | 12.7 54.9 265 11 5 9.9 5.4 11250 13.7 56.7 225 17 9 9.6 5.2 | 13.4 56.1 265 11 5 9.2 5.0 11000 14.4 57.9 225 17 9 9.6 5.3 | 14.1 57.4 265 11 5 9.2 5.0 10750 15.1 59.2 225 17 9 11.2 6.1 | 14.8 58.6 265 11 5 10.9 6.0 10500 16.0 60.8 220 17 9 11.4 6.2 | 15.7 60.3 265 10 5 11.0 6.0 10250 16.8 62.2 220 17 9 9.9 5.5 | 16.4 61.5 265 10 5 9.4 5.2 10000 17.5 63.5 220 16 8 10.4 5.7 | 17.1 62.8 265 10 5 9.5 5.2 9750 18.3 64.9 220 16 8 9.0 5.0 | 17.8 64.0 265 10 5 9.6 5.3 9500 19.1 66.4 220 16 8 15.3 8.4 | 18.6 65.5 265 10 5 11.5 6.3 9250 20.7 69.3 220 14 7 30.6 16.8 | 19.5 67.1 265 9 5 14.2 7.8 9000 22.6 72.7 220 13 7 9.3 5.1 | 20.4 68.7 265 8 4 10.4 5.7 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