Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
974 UXUS97 KPUB 211221 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0621 MDT Friday, June 21, 2024 This forecast is for Villa Grove, CO for Friday, June 21, 2024: If the trigger temperature of 62.9 F/17.2 C is reached...then Thermal Soaring Index....................... Excellent Maximum rate of lift........................ 817 ft/min (4.2 m/s) Maximum height of thermals.................. 18274 ft MSL (9302 ft AGL) Forecast maximum temperature................... 76.0 F/24.9 C Time of trigger temperature.................... 1030 MDT Time of overdevelopment........................ 1600 MDT 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................. 16305 ft MSL (7333 ft AGL) Thermal soaring outlook for Saturday 06/22..... Excellent Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:40:38 / 20:30:29 MDT Total possible sunshine........... 14 hr 49 min 51 sec (889 min 51 sec) Altitude of sun at 13:05:34 MDT... 75.12 degrees Upper air data from numerical model forecast valid on 06/21/2024 at 0600 MDT Freezing level.................. 15780 ft MSL (6808 ft AGL) Convective condensation level... 12328 ft MSL (3356 ft AGL) Lifted condensation level....... 15580 ft MSL (6608 ft AGL) Lifted index.................... -5.0 K index......................... +27.3 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 -63.5 -82.3 230 50 26 2.7 1.5 M M M M M 45000 -57.4 -71.3 235 75 39 5.9 3.2 M M M M M 40000 -48.4 -55.1 235 77 40 6.6 3.6 M M M M M 38000 -44.4 -47.9 230 70 36 6.6 3.6 M M M M M 36000 -40.5 -40.9 225 64 33 6.8 3.7 M M M M M 34000 -36.2 -33.2 225 53 27 7.2 3.9 M M M M M 32000 -31.9 -25.4 225 42 22 6.9 3.8 M M M M M 30000 -26.5 -15.7 225 38 20 8.1 4.4 38.0 100.4 10.7 M M 29000 -24.1 -11.4 225 37 19 8.1 4.5 37.5 99.4 10.3 M M 28000 -21.8 -7.2 225 35 18 7.2 3.9 36.8 98.3 9.9 M M 27000 -19.7 -3.5 230 34 17 7.3 4.0 35.8 96.5 9.1 M M 26000 -17.5 0.5 240 32 17 7.4 4.0 35.0 94.9 8.5 M M 25000 -15.4 4.3 245 32 16 7.0 3.8 34.2 93.6 7.9 M M 24000 -13.5 7.7 245 34 18 6.4 3.5 32.9 91.3 6.8 M M 23000 -11.6 11.1 245 37 19 6.4 3.5 31.8 89.2 5.8 M M 22000 -9.8 14.4 250 40 20 6.2 3.4 30.7 87.3 4.9 M M 21000 -8.1 17.4 245 41 21 5.8 3.2 29.3 84.7 3.6 M M 20000 -6.5 20.3 240 42 22 5.8 3.2 27.9 82.3 2.4 M M 19500 -5.6 21.9 235 42 22 5.9 3.2 27.3 81.2 1.8 M M 19000 -4.9 23.2 235 43 22 5.1 2.8 26.6 79.9 1.2 M M 18500 -4.1 24.6 235 44 23 5.2 2.8 25.8 78.5 0.4 M M 18000 -3.4 25.9 235 44 23 5.1 2.8 25.1 77.2 -0.3 803 4.1 17500 -2.7 27.1 230 45 23 4.9 2.7 24.3 75.7 -1.0 767 3.9 17000 -2.0 28.4 230 46 24 4.9 2.7 23.5 74.3 -1.8 731 3.7 16500 -1.3 29.7 230 46 24 5.3 2.9 22.8 73.0 -2.6 694 3.5 16000 -0.5 31.1 230 46 24 5.3 2.9 22.0 71.6 -3.3 657 3.3 15500 0.3 32.5 225 47 24 6.1 3.3 21.3 70.4 -4.0 620 3.1 15000 1.7 35.1 225 46 24 6.9 3.8 20.6 69.0 -4.8 555 2.8 14500 2.5 36.5 220 46 24 6.2 3.4 20.0 68.0 -5.4 514 2.6 14000 3.5 38.3 220 44 22 7.0 3.9 19.6 67.2 -5.9 470 2.4 13500 4.5 40.1 220 41 21 6.5 3.6 19.2 66.5 -6.4 426 2.2 13000 5.4 41.7 215 36 18 6.8 3.7 18.7 65.6 -7.0 384 2.1 12500 6.3 43.3 215 31 16 6.4 3.5 18.2 64.7 -7.6 341 1.7 12000 7.2 45.0 210 27 14 5.8 3.2 17.6 63.7 -8.3 302 1.5 11750 7.6 45.7 210 25 13 6.1 3.3 17.3 63.1 -8.6 282 1.4 11500 8.0 46.4 205 24 12 5.6 3.1 17.0 62.6 -8.9 263 1.3 11250 8.3 46.9 205 22 12 4.8 2.7 16.6 62.0 -9.3 244 1.2 11000 8.7 47.7 205 21 11 4.8 2.6 16.3 61.3 -9.8 227 1.2 10750 9.0 48.2 200 19 10 4.6 2.5 15.9 60.6 -10.2 210 1.1 10500 9.3 48.7 200 18 9 4.0 2.2 15.5 59.9 -10.6 193 1.0 10250 9.6 49.3 195 16 8 3.6 2.0 15.0 59.0 -11.1 178 0.9 10000 9.8 49.6 195 13 7 3.5 1.9 14.5 58.2 -11.6 163 0.8 9750 10.1 50.2 195 10 5 3.4 1.9 14.1 57.4 -12.1 148 0.8 9500 10.3 50.5 190 7 4 5.1 2.8 13.7 56.6 -12.6 132 0.7 9250 10.8 51.4 190 4 2 8.5 4.7 13.4 56.2 -12.9 111 0.6 9000 11.3 52.3 185 1 0 3.9 2.2 13.3 55.9 -13.1 87 0.4 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 * * * * * * 06/21/2024 at 0900 MDT | 06/21/2024 at 1200 MDT | CAPE... +9.2 LI... -0.8 | CAPE... +304.8 LI... -1.0 CINH... -15.5 K Index... +27.1 | CINH... -8.0 K Index... +23.4 | 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 -63.6 -82.5 235 52 27 3.3 1.8 | -64.5 -84.1 235 55 29 3.4 1.9 45000 -56.9 -70.4 240 75 39 5.8 3.2 | -57.3 -71.1 240 79 41 6.4 3.5 40000 -47.8 -54.0 235 82 42 7.0 3.8 | -47.5 -53.5 235 85 44 7.2 4.0 38000 -43.6 -46.5 230 76 39 7.0 3.8 | -43.2 -45.8 235 78 40 7.2 4.0 36000 -39.4 -38.9 225 70 36 6.9 3.8 | -38.9 -38.0 230 71 36 6.8 3.8 34000 -35.4 -31.7 225 64 33 6.6 3.6 | -35.1 -31.2 225 67 35 6.2 3.4 32000 -31.0 -23.8 220 57 29 6.4 3.5 | -30.9 -23.6 220 64 33 6.2 3.4 30000 -27.4 -17.3 215 50 26 6.0 3.3 | -27.3 -17.1 220 57 30 6.0 3.3 29000 -25.7 -14.3 215 47 24 6.1 3.4 | -25.5 -13.9 220 54 28 6.0 3.3 28000 -23.8 -10.8 210 44 23 8.2 4.5 | -23.7 -10.7 220 50 26 6.5 3.6 27000 -21.4 -6.5 215 42 22 8.0 4.4 | -21.7 -7.1 220 47 24 6.5 3.6 26000 -19.0 -2.2 215 41 21 8.0 4.4 | -19.8 -3.6 225 44 22 6.5 3.6 25000 -16.6 2.1 220 40 20 7.4 4.0 | -17.8 -0.0 225 40 21 7.4 4.0 24000 -14.7 5.5 220 37 19 6.4 3.5 | -15.3 4.5 225 37 19 8.4 4.6 23000 -12.9 8.8 225 34 18 6.5 3.6 | -12.8 9.0 220 34 17 8.4 4.6 22000 -11.0 12.2 230 32 16 6.7 3.7 | -10.3 13.5 220 30 16 7.1 3.9 21000 -9.1 15.6 240 35 18 6.8 3.7 | -8.6 16.5 225 29 15 6.0 3.3 20000 -7.1 19.2 245 39 20 6.8 3.8 | -6.9 19.6 235 29 15 6.3 3.5 19500 -6.1 21.0 245 41 21 7.0 3.9 | -6.1 21.0 240 29 15 6.5 3.5 19000 -5.2 22.6 245 42 22 5.2 2.8 | -5.2 22.6 245 28 15 7.1 3.9 18500 -4.5 23.9 250 42 22 5.4 2.9 | -4.2 24.4 250 28 14 7.1 3.9 18000 -3.7 25.3 250 43 22 5.5 3.0 | -3.2 26.2 255 27 14 6.8 3.7 17500 -2.9 26.8 250 42 21 5.7 3.1 | -2.3 27.9 260 27 14 6.3 3.5 17000 -2.1 28.2 250 40 21 5.6 3.1 | -1.4 29.5 265 27 14 6.3 3.5 16500 -1.3 29.7 250 39 20 6.1 3.3 | -0.5 31.1 270 27 14 5.7 3.1 16000 -0.5 31.1 250 37 19 6.0 3.3 | 0.3 32.5 270 27 14 5.7 3.1 15500 0.9 33.6 245 36 18 6.6 3.6 | 1.6 34.9 275 26 13 7.1 3.9 15000 1.8 35.2 245 35 18 6.6 3.6 | 2.6 36.7 280 24 12 7.1 3.9 14500 2.7 36.9 240 33 17 5.0 2.8 | 3.5 38.3 280 23 12 6.1 3.4 14000 3.3 37.9 245 31 16 4.4 2.4 | 4.5 40.1 275 25 13 6.5 3.6 13500 3.9 39.0 245 28 14 4.7 2.6 | 5.4 41.7 270 26 13 6.5 3.6 13000 4.5 40.1 250 24 13 3.1 1.7 | 6.2 43.2 265 27 14 5.8 3.2 12500 5.0 41.0 260 21 11 3.6 2.0 | 7.0 44.6 260 28 14 5.8 3.2 12000 5.7 42.3 270 21 11 4.0 2.2 | 7.8 46.0 255 28 14 6.4 3.5 11750 6.0 42.8 270 21 11 3.7 2.0 | 8.3 46.9 255 27 14 7.3 4.0 11500 6.3 43.3 275 21 11 3.3 1.8 | 8.8 47.8 255 27 14 7.4 4.1 11250 6.5 43.7 280 22 11 2.7 1.5 | 9.4 48.9 250 25 13 7.9 4.3 11000 6.7 44.1 280 22 11 3.0 1.6 | 10.0 50.0 250 23 12 7.9 4.3 10750 6.9 44.4 280 22 11 2.2 1.2 | 10.5 50.9 245 21 11 7.8 4.3 10500 7.0 44.6 280 22 11 4.6 2.5 | 11.2 52.2 240 19 10 9.5 5.2 10250 7.5 45.5 280 20 10 7.5 4.1 | 11.9 53.4 240 18 9 11.0 6.1 10000 8.0 46.4 280 18 9 7.2 4.0 | 12.8 55.0 240 18 9 11.9 6.5 9750 8.5 47.3 280 16 8 7.4 4.1 | 13.6 56.5 240 17 9 8.6 4.7 9500 9.0 48.2 280 14 7 10.1 5.5 | 14.3 57.7 235 16 8 14.3 7.8 9250 9.9 49.8 275 11 6 14.3 7.8 | 16.0 60.8 235 14 7 33.9 18.6 9000 10.8 51.4 275 8 4 7.0 3.8 | 17.9 64.2 235 13 7 2.8 1.5 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 06/21/2024 at 1500 MDT | 06/21/2024 at 1800 MDT | CAPE... +943.1 LI... -3.3 | CAPE... +770.9 LI... -2.9 CINH... 0.0 K Index... +20.4 | CINH... -0.0 K Index... +16.2 | 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 -64.1 -83.4 235 57 29 3.2 1.8 | -64.0 -83.2 245 61 32 2.7 1.5 45000 -57.0 -70.6 245 81 42 6.5 3.6 | -57.3 -71.1 245 83 43 7.1 3.9 40000 -47.1 -52.8 240 92 47 6.9 3.8 | -46.6 -51.9 240 94 48 7.2 3.9 38000 -43.0 -45.4 235 83 43 6.9 3.8 | -42.3 -44.1 240 86 44 7.2 4.0 36000 -38.8 -37.8 235 75 38 6.6 3.6 | -38.0 -36.4 240 79 41 6.7 3.7 34000 -35.2 -31.4 230 72 37 6.1 3.3 | -34.4 -29.9 240 68 35 5.9 3.2 32000 -31.0 -23.8 230 69 35 6.2 3.4 | -30.5 -22.9 240 55 28 6.3 3.4 30000 -27.3 -17.1 230 63 32 6.3 3.5 | -26.9 -16.4 240 47 24 6.0 3.3 29000 -25.4 -13.7 230 60 31 6.3 3.5 | -25.0 -13.0 245 44 23 6.0 3.3 28000 -23.4 -10.1 230 57 29 7.1 3.9 | -23.1 -9.6 245 41 21 7.9 4.3 27000 -21.3 -6.3 230 52 27 7.0 3.9 | -20.8 -5.4 245 41 21 7.7 4.2 26000 -19.2 -2.6 230 48 25 7.0 3.9 | -18.5 -1.3 245 40 21 7.7 4.2 25000 -17.1 1.2 230 43 22 7.0 3.9 | -16.2 2.8 245 40 21 7.2 3.9 24000 -15.0 5.0 230 39 20 7.0 3.9 | -14.2 6.4 240 37 19 6.6 3.6 23000 -12.9 8.8 230 35 18 7.0 3.9 | -12.2 10.0 240 35 18 6.6 3.6 22000 -10.7 12.7 230 31 16 6.8 3.8 | -10.3 13.5 240 32 16 6.7 3.7 21000 -8.8 16.2 235 31 16 6.8 3.7 | -8.3 17.1 240 30 15 6.7 3.7 20000 -6.8 19.8 240 31 16 7.0 3.8 | -6.3 20.7 240 27 14 6.7 3.7 19500 -5.9 21.4 240 31 16 7.2 4.0 | -5.3 22.5 240 26 13 6.7 3.7 19000 -4.9 23.2 245 31 16 7.0 3.8 | -4.4 24.1 240 25 13 7.0 3.9 18500 -3.9 25.0 245 30 16 7.2 3.9 | -3.4 25.9 245 24 12 7.1 3.9 18000 -3.0 26.6 245 30 15 7.1 3.9 | -2.4 27.7 250 24 12 7.1 3.9 17500 -2.0 28.4 250 30 15 6.8 3.7 | -1.4 29.5 255 23 12 7.1 3.9 17000 -1.0 30.2 250 30 15 6.8 3.7 | -0.5 31.1 255 23 12 7.2 4.0 16500 -0.0 32.0 255 29 15 6.9 3.8 | 0.5 32.9 260 22 11 6.5 3.6 16000 1.0 33.8 255 27 14 6.9 3.8 | 1.4 34.5 260 19 10 6.6 3.6 15500 2.4 36.3 260 22 11 6.2 3.4 | 2.3 36.1 260 16 8 6.6 3.6 15000 3.2 37.8 260 17 9 6.2 3.4 | 3.6 38.5 245 12 6 6.5 3.6 14500 4.2 39.6 260 14 7 7.4 4.1 | 4.6 40.3 240 12 6 7.4 4.0 14000 5.2 41.4 255 14 7 7.7 4.2 | 5.6 42.1 230 12 6 7.4 4.1 13500 6.3 43.3 245 14 7 7.1 3.9 | 6.6 43.9 220 13 7 6.2 3.4 13000 7.2 45.0 240 16 8 7.6 4.2 | 7.7 45.9 215 14 7 10.0 5.5 12500 8.3 46.9 235 16 8 7.5 4.1 | 9.0 48.2 210 14 7 9.1 5.0 12000 9.3 48.7 230 16 8 8.7 4.8 | 10.2 50.4 210 14 7 9.6 5.3 11750 9.9 49.8 225 16 8 10.1 5.5 | 11.0 51.8 210 14 7 10.9 6.0 11500 10.6 51.1 225 16 8 9.6 5.3 | 11.8 53.2 210 13 7 10.3 5.6 11250 11.3 52.3 225 16 8 9.5 5.2 | 12.5 54.5 210 13 7 9.8 5.4 11000 12.0 53.6 220 16 8 9.4 5.1 | 13.2 55.8 210 13 7 9.7 5.3 10750 12.8 55.0 220 16 8 10.5 5.7 | 14.0 57.2 210 13 7 10.5 5.8 10500 13.6 56.5 220 16 8 11.3 6.2 | 14.8 58.6 210 13 7 10.8 5.9 10250 14.4 57.9 220 16 8 10.7 5.8 | 15.6 60.1 210 13 7 9.9 5.5 10000 15.2 59.4 220 16 8 11.3 6.2 | 16.3 61.3 210 13 7 10.0 5.5 9750 16.0 60.8 220 16 8 9.2 5.0 | 17.0 62.6 210 12 6 9.5 5.2 9500 16.8 62.2 220 15 8 15.2 8.3 | 17.8 64.0 210 12 6 12.8 7.0 9250 18.5 65.3 220 14 7 32.8 18.0 | 19.0 66.2 205 11 6 20.7 11.4 9000 20.6 69.1 215 13 7 12.7 7.0 | 20.4 68.7 205 10 5 14.3 7.9 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