Soaring Guidance
Issued by NWS Pueblo, CO

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310
UXUS97 KPUB 041211
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0610 MDT Friday, July 4, 2025

This forecast is for Villa Grove, CO for Friday, July 4, 2025:

If the trigger temperature of 63.1 F/17.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 962 ft/min (4.9 m/s)
   Maximum height of thermals.................. 21761 ft MSL (12773 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 0830 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................. 18365 ft MSL (9376 ft AGL)
Thermal soaring outlook for Saturday 07/05..... Excellent

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 05:45:46 / 20:30:29 MDT
Total possible sunshine........... 14 hr 44 min 43 sec (884 min 43 sec)
Altitude of sun at 13:08:08 MDT... 74.43 degrees

Upper air data from numerical model forecast valid on 07/04/2025 at 0600 MDT

Freezing level.................. 15405 ft MSL (6417 ft AGL)
Convective condensation level... 15238 ft MSL (6250 ft AGL)
Lifted condensation level....... 18533 ft MSL (9544 ft AGL)
Lifted index.................... -4.8
K index......................... +9.2

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  -63.4 -82.1   220   25   13   3.4   1.8      M     M       M      M    M
 45000  -57.0 -70.6   225   32   17   5.9   3.2      M     M       M      M    M
 40000  -48.1 -54.6   215   42   22   6.0   3.3      M     M       M      M    M
 38000  -44.5 -48.1   225   41   21   6.0   3.3      M     M       M      M    M
 36000  -40.9 -41.6   235   41   21   6.0   3.3      M     M       M      M    M
 34000  -37.0 -34.6   235   39   20   6.5   3.6      M     M       M      M    M
 32000  -32.6 -26.7   230   36   19   6.6   3.6      M     M       M      M    M
 30000  -28.3 -18.9   225   33   17   7.2   3.9   36.1  97.0     7.1      M    M
 29000  -26.2 -15.2   220   31   16   7.2   3.9   35.2  95.4     6.4      M    M
 28000  -24.0 -11.2   215   29   15   7.0   3.8   34.4  93.9     5.8      M    M
 27000  -22.0  -7.6   215   27   14   6.9   3.8   33.2  91.8     4.9      M    M
 26000  -19.9  -3.8   215   25   13   6.9   3.8   32.2  89.9     4.1      M    M
 25000  -17.9  -0.2   215   23   12   7.0   3.8   31.2  88.2     3.3      M    M
 24000  -16.0   3.2   215   21   11   6.3   3.5   30.0  86.0     2.3      M    M
 23000  -14.1   6.6   215   19   10   6.3   3.5   28.8  83.8     1.2      M    M
 22000  -12.2  10.0   215   17    9   6.4   3.5   27.7  81.9     0.2      M    M
 21000  -10.0  14.0   215   16    8   7.5   4.1   26.8  80.2    -0.5   1093  5.6
 20000   -7.8  18.0   220   15    7   7.5   4.1   26.0  78.8    -1.2    996  5.1
 19500   -6.6  20.1   220   14    7   7.6   4.2   25.7  78.2    -1.5    947  4.8
 19000   -5.6  21.9   220   14    7   5.8   3.2   25.2  77.4    -1.9    901  4.6
 18500   -4.8  23.4   225   14    7   5.5   3.0   24.5  76.1    -2.7    864  4.4
 18000   -4.1  24.6   230   14    7   5.4   3.0   23.8  74.9    -3.4    826  4.2
 17500   -3.6  25.5   240   14    7   3.7   2.0   22.9  73.2    -4.3    795  4.0
 17000   -3.1  26.4   245   13    7   4.0   2.2   21.9  71.5    -5.4    767  3.9
 16500   -2.1  28.2   255   12    6   7.1   3.9   20.9  69.6    -6.6    714  3.6
 16000   -1.1  30.0   255   12    6   6.8   3.7   20.5  68.8    -7.1    670  3.4
 15500    0.0  32.0   260   12    6   9.2   5.0   20.2  68.3    -7.5    621  3.2
 15000    1.4  34.5   260   11    6   9.5   5.2   20.1  68.1    -7.7    566  2.9
 14500    2.6  36.7   265   11    6   6.6   3.6   19.8  67.7    -8.0    516  2.6
 14000    3.6  38.5   270   13    6   6.9   3.8   19.4  66.8    -8.5    470  2.4
 13500    4.6  40.3   275   14    7   6.1   3.3   18.9  66.1    -8.9    425  2.2
 13000    5.4  41.7   285   16    8   6.1   3.4   18.3  64.9    -9.6    385  2.0
 12500    6.3  43.3   290   18    9   5.9   3.3   17.7  63.9   -10.2    344  1.7
 12000    7.2  45.0   290   20   10   5.3   2.9   17.1  62.8   -10.9    304  1.5
 11750    7.5  45.5   290   21   11   4.7   2.6   16.7  62.1   -11.3    286  1.5
 11500    7.8  46.0   290   22   11   4.8   2.6   16.3  61.4   -11.8    269  1.4
 11250    8.1  46.6   290   22   11   4.5   2.5   15.9  60.7   -12.2    252  1.3
 11000    8.4  47.1   290   22   11   4.5   2.5   15.5  60.0   -12.7    236  1.2
 10750    8.8  47.8   290   22   11   4.2   2.3   15.1  59.2   -13.1    219  1.1
 10500    9.0  48.2   290   22   11   3.8   2.1   14.7  58.4   -13.6    205  1.0
 10250    9.2  48.6   290   22   11   4.3   2.3   14.2  57.6   -14.2    190  1.0
 10000    9.5  49.1   285   20   10   4.2   2.3   13.8  56.9   -14.7    175  0.9
  9750    9.7  49.5   285   19   10   5.2   2.9   13.4  56.2   -15.2    160  0.8
  9500   10.1  50.2   280   17    9   5.7   3.2   13.1  55.6   -15.6    141  0.7
  9250   10.4  50.7   275   13    7   0.9   0.5   12.7  54.8   -16.1    126  0.6
  9000   10.1  50.2   265    8    4  -7.0  -3.8   11.7  53.1   -17.1    126  0.6
  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 * * * * * *

           07/04/2025 at 0900 MDT          |       07/04/2025 at 1200 MDT
                                           |
CAPE...  +144.9    LI...       -1.3        | CAPE...  +202.1    LI...       -2.1
CINH...   -16.8    K Index... +11.6        | CINH...   -12.1    K Index... +19.4
                                           |
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 -63.7 -82.7  230  26 13   2.9   1.6 | -63.6 -82.5  225  24 13   2.9   1.6
 45000 -57.4 -71.3  230  36 19   6.5   3.6 | -57.4 -71.3  230  35 18   6.3   3.5
 40000 -47.8 -54.0  225  44 23   5.8   3.2 | -47.9 -54.2  230  42 22   6.3   3.5
 38000 -44.3 -47.7  230  42 21   5.8   3.2 | -44.1 -47.4  235  43 22   6.3   3.5
 36000 -40.8 -41.4  235  39 20   5.7   3.1 | -40.3 -40.5  240  43 22   6.4   3.5
 34000 -37.0 -34.6  235  37 19   6.4   3.5 | -36.3 -33.3  240  39 20   5.8   3.2
 32000 -32.6 -26.7  235  34 17   6.4   3.5 | -32.8 -27.0  240  34 18   5.8   3.2
 30000 -27.9 -18.2  240  31 16   8.0   4.4 | -28.6 -19.5  240  32 16   7.1   3.9
 29000 -25.5 -13.9  240  30 16   8.0   4.4 | -26.5 -15.7  240  31 16   7.1   3.9
 28000 -23.2  -9.8  240  29 15   6.5   3.5 | -24.3 -11.7  245  29 15   8.1   4.4
 27000 -21.4  -6.5  240  27 14   5.9   3.3 | -21.8  -7.2  250  28 14   8.3   4.5
 26000 -19.6  -3.3  235  26 13   5.9   3.3 | -19.3  -2.7  255  26 13   8.3   4.5
 25000 -17.9  -0.2  235  24 12   6.0   3.3 | -16.8   1.8  265  25 13   7.8   4.3
 24000 -16.2   2.8  230  22 11   5.7   3.1 | -15.5   4.1  265  23 12   3.5   1.9
 23000 -14.5   5.9  230  20 10   5.8   3.2 | -14.5   5.9  265  21 11   3.6   2.0
 22000 -12.8   9.0  225  18  9   5.9   3.2 | -13.4   7.9  260  20 10   4.3   2.4
 21000 -11.0  12.2  230  16  8   6.1   3.4 | -11.6  11.1  265  18  9   6.8   3.8
 20000  -9.2  15.4  235  15  8   6.1   3.4 |  -9.6  14.7  270  17  9   7.0   3.8
 19500  -8.2  17.2  235  15  7   6.1   3.4 |  -8.7  16.3  275  17  9   7.1   3.9
 19000  -7.4  18.7  240  14  7   6.1   3.3 |  -7.6  18.3  275  16  8   7.5   4.1
 18500  -6.5  20.3  250  13  7   6.2   3.4 |  -6.6  20.1  280  15  8   7.5   4.1
 18000  -5.7  21.7  260  12  6   6.5   3.6 |  -5.5  22.1  285  15  7   7.7   4.2
 17500  -4.7  23.5  265  12  6   7.4   4.1 |  -4.3  24.3  285  14  7   8.1   4.4
 17000  -3.7  25.3  270  11  6   7.5   4.1 |  -3.2  26.2  290  13  7   8.1   4.4
 16500  -2.6  27.3  280  11  6   8.2   4.5 |  -1.4  29.5  295  12  6   7.6   4.2
 16000  -0.8  30.6  290  12  6   8.4   4.6 |  -0.3  31.5  295  12  6   7.6   4.2
 15500   0.4  32.7  295  13  6   7.4   4.1 |   0.8  33.4  300  11  6   7.2   3.9
 15000   1.5  34.7  300  14  7   7.6   4.2 |   1.8  35.2  300  11  5   7.2   3.9
 14500   2.5  36.5  300  15  8   6.2   3.4 |   2.9  37.2  300  12  6   6.5   3.5
 14000   3.4  38.1  305  17  9   6.3   3.5 |   3.7  38.7  300  16  8   5.8   3.2
 13500   4.3  39.7  305  20 10   7.0   3.9 |   4.6  40.3  305  20 10   6.0   3.3
 13000   5.1  41.2  305  22 11   4.1   2.2 |   5.4  41.7  300  21 11   7.3   4.0
 12500   5.7  42.3  305  24 12   4.4   2.4 |   6.4  43.5  295  21 11   8.2   4.5
 12000   6.3  43.3  300  25 13   4.3   2.4 |   7.7  45.9  290  19 10   9.8   5.4
 11750   6.6  43.9  300  24 12   3.9   2.2 |   8.5  47.3  290  19 10  10.2   5.6
 11500   6.9  44.4  300  24 12   4.6   2.5 |   9.2  48.6  290  18 10  10.0   5.5
 11250   7.2  45.0  295  23 12   6.1   3.3 |   9.9  49.8  290  18  9   9.8   5.4
 11000   7.6  45.7  295  21 11   6.1   3.3 |  10.7  51.3  290  18  9   9.7   5.3
 10750   8.0  46.4  290  20 10   7.7   4.2 |  11.4  52.5  290  18  9  10.3   5.6
 10500   8.7  47.7  290  19 10  10.0   5.5 |  12.2  54.0  290  17  9  11.1   6.1
 10250   9.4  48.9  285  18  9  10.5   5.8 |  13.0  55.4  290  17  9  11.2   6.1
 10000  10.2  50.4  285  17  9  11.2   6.2 |  13.9  57.0  290  17  9  11.9   6.6
  9750  11.0  51.8  285  16  8   9.9   5.4 |  14.7  58.5  290  16  8   9.5   5.2
  9500  11.8  53.2  285  15  8  13.9   7.6 |  15.5  59.9  290  16  8  16.2   8.9
  9250  13.2  55.8  285  14  7  25.5  14.0 |  17.5  63.5  290  14  7  36.7  20.2
  9000  15.0  59.0  285  12  6  15.2   8.4 |  19.9  67.8  290  13  7  16.4   9.0
  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

           07/04/2025 at 1500 MDT          |       07/04/2025 at 1800 MDT
                                           |
CAPE...  +416.4    LI...       -2.1        | CAPE...  +296.4    LI...       -1.1
CINH...    -0.5    K Index... +22.9        | CINH...    -2.8    K Index... +10.5
                                           |
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 -63.5 -82.3  215  26 14   2.4   1.3 | -63.9 -83.0  215  29 15   2.6   1.4
 45000 -57.9 -72.2  220  39 20   6.3   3.4 | -58.0 -72.4  225  41 21   6.4   3.5
 40000 -48.0 -54.4  230  49 25   6.5   3.5 | -48.0 -54.4  240  51 26   6.6   3.6
 38000 -44.1 -47.4  235  50 26   6.5   3.5 | -44.0 -47.2  245  53 27   6.6   3.6
 36000 -40.2 -40.4  240  52 27   6.3   3.4 | -40.1 -40.2  250  55 28   6.2   3.4
 34000 -36.9 -34.4  240  45 23   5.6   3.1 | -37.0 -34.6  250  48 25   5.0   2.7
 32000 -33.5 -28.3  240  37 19   5.5   3.0 | -34.0 -29.2  250  40 21   4.8   2.6
 30000 -29.5 -21.1  245  31 16   7.0   3.8 | -29.9 -21.8  250  34 18   7.2   4.0
 29000 -27.4 -17.3  245  28 15   7.0   3.8 | -27.7 -17.9  250  31 16   7.2   4.0
 28000 -24.8 -12.6  250  25 13   6.9   3.8 | -25.1 -13.2  255  29 15   6.7   3.7
 27000 -22.7  -8.9  255  25 13   6.9   3.8 | -23.0  -9.4  260  28 15   6.8   3.7
 26000 -20.6  -5.1  265  24 13   6.9   3.8 | -21.0  -5.8  265  28 15   6.8   3.7
 25000 -18.5  -1.3  270  24 13   6.9   3.8 | -19.0  -2.2  270  29 15   7.1   3.9
 24000 -16.5   2.3  275  23 12   6.8   3.7 | -16.8   1.8  270  26 13   7.3   4.0
 23000 -14.5   5.9  285  23 12   6.8   3.8 | -14.6   5.7  275  24 12   7.3   4.0
 22000 -12.5   9.5  295  23 12   6.7   3.7 | -12.4   9.7  280  21 11   7.1   3.9
 21000 -10.6  12.9  290  21 11   6.5   3.6 | -10.4  13.3  280  20 10   7.0   3.8
 20000  -8.7  16.3  290  19 10   6.8   3.7 |  -8.3  17.1  285  18  9   7.0   3.8
 19500  -7.8  18.0  290  18  9   6.9   3.8 |  -7.3  18.9  285  17  9   7.0   3.9
 19000  -6.8  19.8  285  16  8   7.6   4.2 |  -6.2  20.8  285  16  8   7.6   4.2
 18500  -5.7  21.7  285  15  7   7.6   4.2 |  -5.1  22.8  280  15  8   7.7   4.2
 18000  -4.6  23.7  285  13  7   7.7   4.2 |  -4.0  24.8  280  15  8   7.8   4.3
 17500  -3.5  25.7  285  13  7   7.9   4.3 |  -3.0  26.6  280  14  7   7.9   4.3
 17000  -2.3  27.9  290  13  7   7.9   4.4 |  -1.9  28.6  285  13  7   8.2   4.5
 16500  -1.2  29.8  290  14  7   7.2   4.0 |  -0.7  30.7  285  13  7   9.1   5.0
 16000  -0.2  31.6  295  15  8   7.3   4.0 |   0.6  33.1  290  13  7   9.1   5.0
 15500   0.9  33.6  300  16  8   8.1   4.4 |   1.8  35.2  290  12  6   9.5   5.2
 15000   2.6  36.7  300  17  9   8.2   4.5 |   3.2  37.8  295  12  6   9.5   5.2
 14500   3.9  39.0  300  17  9  10.1   5.5 |   5.3  41.5  295  12  6   9.6   5.3
 14000   5.3  41.5  300  17  9   9.4   5.2 |   6.8  44.2  295  12  6  10.0   5.5
 13500   6.7  44.1  300  17  9  10.4   5.7 |   8.1  46.6  295  12  6   8.7   4.8
 13000   8.1  46.6  300  17  9   9.4   5.2 |   9.5  49.1  295  12  6  10.3   5.6
 12500   9.6  49.3  300  17  9   9.8   5.4 |  11.0  51.8  295  11  6  10.3   5.7
 12000  11.1  52.0  300  16  8  10.2   5.6 |  12.6  54.7  295  11  6  10.1   5.5
 11750  11.8  53.2  300  16  8  10.3   5.6 |  13.3  55.9  295  11  6  10.0   5.5
 11500  12.6  54.7  300  16  8  10.0   5.5 |  14.1  57.4  295  11  6   9.5   5.2
 11250  13.3  55.9  300  16  8   9.6   5.2 |  14.7  58.5  295  11  6   8.9   4.9
 11000  14.0  57.2  300  16  8   9.6   5.3 |  15.4  59.7  295  11  6   9.0   4.9
 10750  14.8  58.6  300  16  8  10.3   5.6 |  16.1  61.0  295  11  6  10.1   5.5
 10500  15.6  60.1  300  16  8  11.0   6.0 |  16.9  62.4  295  11  6  10.8   5.9
 10250  16.4  61.5  300  15  8  10.8   5.9 |  17.7  63.9  295  11  5  10.5   5.7
 10000  17.2  63.0  300  15  8  11.4   6.3 |  18.5  65.3  295  10  5  10.8   5.9
  9750  18.0  64.4  300  15  8   9.4   5.1 |  19.3  66.7  300  10  5   9.8   5.4
  9500  18.8  65.8  300  14  7  15.9   8.7 |  20.0  68.0  300  10  5  13.4   7.4
  9250  20.7  69.3  300  14  7  35.4  19.4 |  21.4  70.5  295   9  5  23.0  12.6
  9000  23.1  73.6  300  13  6  18.2  10.0 |  22.9  73.2  295   9  4  11.9   6.5
  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
________________________________________________________________________________

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.

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