Soaring Guidance
Issued by NWS Pueblo, CO
Issued by NWS Pueblo, CO
890 UXUS97 KPUB 141409 SRGPUB Soaring Forecast National Weather Service Pueblo, Colorado 0809 MDT Friday, June 14, 2024 This forecast is for Villa Grove, CO for Friday, June 14, 2024: If the trigger temperature of 69.2 F/20.6 C is reached...then Thermal Soaring Index....................... Fair Maximum rate of lift........................ 1156 ft/min (5.9 m/s) Maximum height of thermals.................. 22218 ft MSL (13258 ft AGL) Forecast maximum temperature................... 78.0 F/26.0 C Time of trigger temperature.................... 0830 MDT Time of overdevelopment........................ 1100 MDT Middle/high clouds during soaring window....... Broken/overcast thin middle Surface winds during soaring window............ More than 30 mph Height of the -3 thermal index................. 14521 ft MSL (5562 ft AGL) Thermal soaring outlook for Saturday 06/15..... Good Wave Soaring Index............................. Not available Remarks... Sunrise/Sunset.................... 05:39:38 / 20:28:28 MDT Total possible sunshine........... 14 hr 48 min 50 sec (888 min 50 sec) Altitude of sun at 13:04:03 MDT... 75.02 degrees Upper air data from numerical model forecast valid on 06/14/2024 at 0600 MDT Freezing level.................. 16779 ft MSL (7819 ft AGL) Convective condensation level... 17675 ft MSL (8715 ft AGL) Lifted condensation level....... 18577 ft MSL (9617 ft AGL) Lifted index.................... -4.7 K index......................... +23.1 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 -61.2 -78.2 250 36 19 2.1 1.2 M M M M M 45000 -56.6 -69.9 240 45 23 4.7 2.6 M M M M M 40000 -49.9 -57.8 225 49 25 2.5 1.4 M M M M M 38000 -48.4 -55.1 225 38 19 2.5 1.4 M M M M M 36000 -46.9 -52.4 225 27 14 2.0 1.1 M M M M M 34000 -42.4 -44.3 215 22 11 8.5 4.6 M M M M M 32000 -36.7 -34.1 205 18 9 8.8 4.8 M M M M M 30000 -31.5 -24.7 210 18 10 8.8 4.8 32.2 90.0 5.3 M M 29000 -28.8 -19.8 210 19 10 8.9 4.9 32.0 89.5 5.1 M M 28000 -26.3 -15.3 215 20 10 7.5 4.1 31.6 88.9 4.8 M M 27000 -24.0 -11.2 215 23 12 7.5 4.1 30.7 87.2 4.1 M M 26000 -21.8 -7.2 215 25 13 7.5 4.1 29.9 85.8 3.5 M M 25000 -19.6 -3.3 215 27 14 7.1 3.9 29.2 84.5 2.9 M M 24000 -17.7 0.1 210 28 15 6.4 3.5 27.9 82.2 1.8 M M 23000 -15.8 3.6 205 29 15 6.4 3.5 26.7 80.1 0.8 M M 22000 -13.9 7.0 205 30 15 7.1 3.9 25.7 78.2 -0.2 1339 6.8 21000 -11.6 11.1 205 28 14 7.9 4.3 24.9 76.9 -0.9 1240 6.3 20000 -9.3 15.3 200 26 13 7.9 4.4 24.3 75.8 -1.5 1140 5.8 19500 -8.1 17.4 200 25 13 8.0 4.4 24.1 75.3 -1.8 1091 5.5 19000 -6.8 19.8 200 24 12 10.0 5.5 24.0 75.1 -1.9 1035 5.3 18500 -5.3 22.5 200 23 12 9.8 5.4 24.0 75.2 -1.9 976 5.0 18000 -3.8 25.2 200 22 12 9.7 5.3 24.0 75.2 -1.9 917 4.7 17500 -2.4 27.7 200 21 11 9.6 5.3 24.0 75.1 -1.9 859 4.4 17000 -0.9 30.4 200 20 10 9.6 5.3 24.0 75.1 -1.9 801 4.1 16500 0.5 32.9 195 19 10 9.4 5.2 23.9 75.0 -2.0 744 3.8 16000 1.9 35.4 195 17 9 9.5 5.2 23.9 74.9 -2.1 687 3.5 15500 3.2 37.8 190 15 8 8.4 4.6 23.8 74.8 -2.2 632 3.2 15000 4.4 39.9 190 14 7 8.1 4.4 23.5 74.3 -2.5 583 3.0 14500 5.9 42.6 185 12 6 6.0 3.3 23.0 73.4 -3.2 514 2.6 14000 6.8 44.2 185 10 5 6.4 3.5 22.4 72.4 -3.8 473 2.4 13500 7.7 45.9 180 9 5 7.9 4.3 22.0 71.6 -4.4 431 2.2 13000 8.8 47.8 185 7 3 6.4 3.5 21.6 70.9 -4.8 384 1.9 12500 9.8 49.6 195 4 2 5.3 2.9 21.1 70.1 -5.3 340 1.7 12000 10.4 50.7 235 2 1 4.9 2.7 20.2 68.4 -6.2 308 1.6 11750 10.8 51.4 275 2 1 6.5 3.5 19.9 67.9 -6.5 287 1.5 11500 11.2 52.2 300 2 1 4.9 2.7 19.6 67.4 -6.8 267 1.4 11250 11.5 52.7 310 3 1 3.7 2.0 19.2 66.6 -7.3 251 1.3 11000 11.8 53.2 315 3 1 3.2 1.8 18.7 65.7 -7.8 236 1.2 10750 12.0 53.6 320 3 2 5.6 3.1 18.3 64.9 -8.2 220 1.1 10500 12.5 54.5 320 3 2 5.1 2.8 18.0 64.5 -8.5 199 1.0 10250 12.7 54.9 325 3 2 2.0 1.1 17.5 63.5 -9.1 186 0.9 10000 12.8 55.0 335 3 1 1.7 1.0 16.9 62.4 -9.7 174 0.9 9750 13.0 55.4 345 3 1 3.4 1.9 16.3 61.4 -10.3 163 0.8 9500 13.0 55.4 360 2 1 -4.9 -2.7 15.7 60.3 -11.0 153 0.8 9250 11.9 53.4 340 3 1 -24.2 -13.3 13.9 56.9 -12.9 181 0.9 9000 10.6 51.1 325 4 2 6.9 3.8 11.9 53.4 -15.0 212 1.1 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 * * * * * * 06/14/2024 at 0900 MDT | 06/14/2024 at 1200 MDT | CAPE... +451.5 LI... -0.6 | CAPE... +883.5 LI... -2.6 CINH... -126.1 K Index... +23.2 | CINH... -2.4 K Index... +28.8 | 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 -60.1 -76.2 255 31 16 2.1 1.2 | -58.6 -73.5 255 25 13 2.6 1.4 45000 -55.8 -68.4 240 44 23 3.9 2.2 | -54.1 -65.4 245 41 21 3.7 2.0 40000 -50.3 -58.5 235 49 25 1.6 0.9 | -48.9 -56.0 235 51 26 0.0 0.0 38000 -49.3 -56.7 230 35 18 1.5 0.8 | -48.7 -55.7 235 42 22 0.3 0.2 36000 -48.4 -55.1 225 21 11 1.1 0.6 | -48.5 -55.3 230 34 17 -0.8 -0.5 34000 -43.7 -46.7 210 18 9 9.2 5.1 | -43.6 -46.5 225 27 14 9.5 5.2 32000 -37.5 -35.5 195 18 9 9.6 5.3 | -37.9 -36.2 210 22 11 9.4 5.2 30000 -32.1 -25.8 205 22 11 8.9 4.9 | -32.6 -26.7 205 25 13 8.7 4.8 29000 -29.5 -21.1 210 25 13 8.9 4.9 | -30.0 -22.0 205 28 15 8.7 4.8 28000 -26.9 -16.4 215 27 14 7.7 4.2 | -27.4 -17.3 205 31 16 8.3 4.6 27000 -24.6 -12.3 215 29 15 7.7 4.2 | -25.1 -13.2 205 34 17 7.9 4.3 26000 -22.3 -8.1 210 31 16 7.7 4.2 | -22.2 -8.0 205 38 19 7.9 4.4 25000 -20.0 -4.0 210 33 17 7.4 4.1 | -19.9 -3.8 205 41 21 7.7 4.2 24000 -18.0 -0.4 210 33 17 6.8 3.7 | -17.7 0.1 200 40 21 7.4 4.0 23000 -16.0 3.2 205 33 17 6.8 3.7 | -15.6 3.9 200 39 20 7.4 4.1 22000 -14.0 6.8 205 34 17 7.4 4.0 | -13.4 7.9 195 39 20 6.9 3.8 21000 -11.6 11.1 205 32 16 8.1 4.5 | -11.5 11.3 195 36 19 6.4 3.5 20000 -9.2 15.4 205 30 15 8.1 4.5 | -9.7 14.5 195 33 17 6.4 3.5 19500 -8.1 17.4 205 29 15 8.1 4.5 | -8.7 16.3 195 32 16 6.4 3.5 19000 -6.8 19.8 205 28 14 9.5 5.2 | -7.6 18.3 190 29 15 8.3 4.6 18500 -5.4 22.3 210 26 14 9.4 5.1 | -6.4 20.5 195 27 14 8.2 4.5 18000 -4.0 24.8 210 25 13 9.4 5.1 | -5.2 22.6 195 24 13 8.0 4.4 17500 -2.6 27.3 210 24 13 9.4 5.1 | -4.1 24.6 200 22 11 7.9 4.3 17000 -1.2 29.8 210 24 12 9.4 5.2 | -3.0 26.6 205 20 10 7.9 4.3 16500 0.1 32.2 210 23 12 8.5 4.7 | -1.8 28.8 210 18 9 8.1 4.5 16000 1.4 34.5 210 22 11 8.6 4.7 | -0.6 30.9 215 16 8 8.1 4.5 15500 2.6 36.7 210 20 10 7.0 3.8 | 0.5 32.9 225 15 8 8.5 4.7 15000 3.4 38.1 210 19 10 6.5 3.6 | 1.8 35.2 225 14 7 8.6 4.7 14500 4.3 39.7 210 17 9 6.6 3.6 | 3.0 37.4 230 13 7 8.4 4.6 14000 5.7 42.3 200 15 8 6.3 3.5 | 4.3 39.7 230 13 7 9.7 5.3 13500 6.6 43.9 200 14 7 6.8 3.8 | 5.7 42.3 235 12 6 9.3 5.1 13000 7.7 45.9 200 11 6 8.2 4.5 | 7.7 45.9 235 12 6 10.4 5.7 12500 9.0 48.2 210 9 5 6.8 3.8 | 9.2 48.6 235 12 6 9.4 5.1 12000 9.8 49.6 230 7 3 6.4 3.5 | 10.5 50.9 235 12 6 10.2 5.6 11750 10.4 50.7 245 6 3 7.6 4.2 | 11.4 52.5 235 12 6 11.7 6.4 11500 10.9 51.6 255 6 3 6.2 3.4 | 12.2 54.0 235 12 6 10.1 5.5 11250 11.3 52.3 265 6 3 4.9 2.7 | 12.9 55.2 235 12 6 8.7 4.8 11000 11.6 52.9 270 6 3 5.0 2.7 | 13.5 56.3 235 12 6 8.8 4.8 10750 12.0 53.6 275 7 3 5.7 3.1 | 14.2 57.6 230 12 6 11.2 6.2 10500 12.4 54.3 280 6 3 7.7 4.2 | 15.1 59.2 230 11 6 11.7 6.4 10250 13.0 55.4 280 6 3 8.7 4.8 | 15.9 60.6 230 11 6 9.6 5.3 10000 13.6 56.5 280 5 2 8.8 4.8 | 16.6 61.9 230 11 6 10.1 5.6 9750 14.3 57.7 280 4 2 8.6 4.7 | 17.4 63.3 230 11 6 9.0 4.9 9500 15.0 59.0 280 3 2 13.8 7.6 | 18.1 64.6 230 11 5 14.4 7.9 9250 16.4 61.5 280 3 1 23.2 12.8 | 19.6 67.3 230 10 5 27.1 14.9 9000 17.8 64.0 285 3 1 8.2 4.5 | 21.3 70.3 235 9 5 8.9 4.9 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 06/14/2024 at 1500 MDT | 06/14/2024 at 1800 MDT | CAPE... +501.2 LI... -1.7 | CAPE... +83.0 LI... -0.2 CINH... -14.9 K Index... +17.3 | CINH... -2.8 K Index... +6.6 | 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 -59.2 -74.6 255 25 13 3.4 1.8 | -61.0 -77.8 250 26 13 3.0 1.6 45000 -54.2 -65.6 245 37 19 3.3 1.8 | -55.5 -67.9 245 28 15 5.1 2.8 40000 -49.3 -56.7 235 40 21 2.1 1.2 | -48.3 -54.9 220 21 11 2.6 1.4 38000 -47.9 -54.2 220 36 18 2.2 1.2 | -46.5 -51.7 180 30 15 2.6 1.5 36000 -46.6 -51.9 205 34 18 1.5 0.8 | -44.9 -48.8 165 44 23 1.9 1.0 34000 -42.3 -44.1 185 31 16 8.0 4.4 | -40.3 -40.5 165 47 24 8.4 4.6 32000 -37.5 -35.5 160 32 16 7.8 4.3 | -35.3 -31.5 170 49 25 8.3 4.5 30000 -32.1 -25.8 160 33 17 9.2 5.1 | -30.7 -23.3 180 47 24 7.6 4.2 29000 -29.4 -20.9 165 33 17 9.2 5.1 | -28.4 -19.1 185 45 23 7.6 4.2 28000 -26.6 -15.9 170 34 17 8.7 4.8 | -26.1 -15.0 190 44 23 7.7 4.2 27000 -24.2 -11.6 175 34 18 8.1 4.5 | -23.7 -10.7 190 45 23 8.0 4.4 26000 -21.8 -7.2 180 36 18 8.2 4.5 | -21.4 -6.5 195 45 23 8.0 4.4 25000 -19.4 -2.9 190 37 19 8.5 4.7 | -19.0 -2.2 200 46 24 8.2 4.5 24000 -17.4 0.7 195 39 20 6.0 3.3 | -16.5 2.3 205 43 22 5.9 3.3 23000 -15.2 4.6 200 42 22 6.1 3.3 | -14.7 5.5 210 40 21 6.0 3.3 22000 -13.5 7.7 205 45 23 6.3 3.5 | -12.9 8.8 220 38 20 6.0 3.3 21000 -11.6 11.1 210 41 21 6.5 3.6 | -11.1 12.0 225 31 16 5.8 3.2 20000 -9.7 14.5 215 39 20 6.5 3.6 | -9.4 15.1 235 24 12 5.8 3.2 19500 -8.7 16.3 220 37 19 6.6 3.6 | -8.5 16.7 240 20 11 5.7 3.1 19000 -7.8 18.0 225 37 19 6.2 3.4 | -7.6 18.3 250 17 9 7.7 4.2 18500 -6.8 19.8 230 37 19 6.2 3.4 | -6.5 20.3 255 14 7 7.8 4.3 18000 -5.9 21.4 235 37 19 7.2 4.0 | -5.4 22.3 265 11 6 7.7 4.2 17500 -4.7 23.5 235 36 18 7.9 4.4 | -4.4 24.1 265 10 5 7.3 4.0 17000 -3.5 25.7 240 35 18 8.0 4.4 | -3.4 25.9 270 10 5 7.4 4.1 16500 -2.3 27.9 245 35 18 8.1 4.4 | -2.4 27.7 265 10 5 7.3 4.0 16000 -1.1 30.0 245 33 17 8.1 4.4 | -1.4 29.5 260 12 6 7.4 4.0 15500 0.1 32.2 245 32 17 8.0 4.4 | -0.3 31.5 255 14 7 7.8 4.3 15000 1.3 34.3 245 31 16 7.9 4.3 | 0.8 33.4 255 14 7 8.1 4.4 14500 2.5 36.5 240 30 16 6.5 3.6 | 2.0 35.6 250 15 7 7.9 4.3 14000 3.6 38.5 240 30 16 9.5 5.2 | 3.2 37.8 245 15 8 8.7 4.8 13500 4.9 40.8 235 30 15 8.4 4.6 | 4.4 39.9 240 16 8 8.8 4.8 13000 5.8 42.4 235 29 15 6.5 3.6 | 5.4 41.7 235 16 8 7.7 4.2 12500 7.0 44.6 235 30 15 8.0 4.4 | 7.0 44.6 235 16 8 10.9 6.0 12000 7.9 46.2 230 29 15 5.2 2.9 | 8.3 46.9 230 16 8 5.7 3.1 11750 8.3 46.9 230 28 15 7.9 4.3 | 8.8 47.8 230 16 8 9.5 5.2 11500 9.0 48.2 230 27 14 10.8 5.9 | 9.7 49.5 230 16 8 13.0 7.1 11250 9.7 49.5 230 26 14 7.7 4.2 | 11.3 52.3 230 16 8 8.9 4.9 11000 10.1 50.2 230 24 13 5.8 3.2 | 12.0 53.6 230 16 8 8.3 4.5 10750 10.5 50.9 235 22 12 5.5 3.0 | 12.6 54.7 225 16 8 10.9 6.0 10500 10.9 51.6 235 20 11 10.7 5.9 | 13.5 56.3 225 16 8 12.0 6.6 10250 11.8 53.2 240 17 9 12.2 6.7 | 14.3 57.7 225 16 8 10.0 5.5 10000 12.5 54.5 245 15 8 8.6 4.7 | 15.1 59.2 225 16 8 9.7 5.3 9750 13.1 55.6 250 14 7 8.9 4.9 | 15.8 60.4 225 16 8 9.6 5.3 9500 13.8 56.8 255 12 6 11.3 6.2 | 16.6 61.9 225 15 8 13.1 7.2 9250 14.9 58.8 265 10 5 20.4 11.2 | 17.8 64.0 225 14 7 20.2 11.1 9000 16.7 62.1 265 10 5 26.9 14.7 | 19.2 66.6 225 12 6 14.7 8.0 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