Soaring Guidance
Issued by NWS Pueblo, CO

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985
UXUS97 KPUB 211210
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0510 MST Thursday, November 21, 2024

This forecast is for Villa Grove, CO for Thursday, November 21, 2024:

If the trigger temperature of 54.2 F/12.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 269 ft/min (1.4 m/s)
   Maximum height of thermals.................. 10985 ft MSL (2014 ft AGL)

Forecast maximum temperature................... 47.0 F/8.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10181 ft MSL (1210 ft AGL)
Thermal soaring outlook for Friday 11/22....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:52:11 / 16:47:03 MST
Total possible sunshine........... 9 hr 54 min 52 sec (594 min 52 sec)
Altitude of sun at 11:49:37 MST... 31.54 degrees

Upper air data from numerical model forecast valid on 11/21/2024 at 0500 MST

Freezing level.................. 9580 ft MSL (609 ft AGL)
Additional freezing level....... 13118 ft MSL (4147 ft AGL)
Convective condensation level... 23838 ft MSL (14867 ft AGL)
Lifted condensation level....... 18929 ft MSL (9958 ft AGL)
Lifted index.................... +10.5
K index......................... -3.0

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  -67.5 -89.5   285   69   36  -1.0  -0.6      M     M       M      M    M
 45000  -68.4 -91.1   285   74   38   4.4   2.4      M     M       M      M    M
 40000  -61.7 -79.1   280   62   32   4.5   2.4      M     M       M      M    M
 38000  -57.2 -71.0   280   61   31   7.9   4.3      M     M       M      M    M
 36000  -52.5 -62.5   285   61   31   7.9   4.3      M     M       M      M    M
 34000  -47.7 -53.9   290   58   30   8.0   4.4      M     M       M      M    M
 32000  -42.9 -45.2   290   52   27   8.0   4.4      M     M       M      M    M
 30000  -38.1 -36.6   290   47   24   8.0   4.4   26.6  79.8    14.3      M    M
 29000  -35.1 -31.2   290   44   23   8.0   4.4   25.7  78.3    13.8      M    M
 28000  -32.7 -26.9   290   42   22   8.1   4.4   25.2  77.3    13.5      M    M
 27000  -30.4 -22.7   290   42   22   7.4   4.1   24.3  75.8    13.0      M    M
 26000  -28.2 -18.8   290   42   22   7.4   4.1   23.4  74.2    12.4      M    M
 25000  -26.0 -14.8   290   42   22   7.4   4.1   22.7  72.8    11.9      M    M
 24000  -23.7 -10.7   285   42   22   7.8   4.3   21.9  71.4    11.4      M    M
 23000  -21.4  -6.5   285   42   22   7.8   4.3   21.2  70.1    10.9      M    M
 22000  -19.1  -2.4   285   42   22   7.8   4.3   20.5  69.0    10.4      M    M
 21000  -16.7   1.9   285   41   21   8.2   4.5   19.9  67.9    10.0      M    M
 20000  -14.2   6.4   285   39   20   8.2   4.5   19.4  66.9     9.7      M    M
 19500  -13.0   8.6   285   38   20   8.2   4.5   19.2  66.5     9.5      M    M
 19000  -11.8  10.8   285   37   19   8.1   4.4   19.0  66.2     9.4      M    M
 18500  -10.6  12.9   285   37   19   7.9   4.4   18.7  65.6     9.1      M    M
 18000   -9.4  15.1   285   36   18   8.0   4.4   18.4  65.1     8.9      M    M
 17500   -8.3  17.1   285   35   18   7.0   3.8   18.0  64.4     8.6      M    M
 17000   -7.3  18.9   285   34   18   7.0   3.9   17.6  63.6     8.2      M    M
 16500   -6.2  20.8   290   33   17   6.6   3.6   17.1  62.8     7.9      M    M
 16000   -5.3  22.5   290   32   17   6.3   3.4   16.5  61.8     7.4      M    M
 15500   -4.3  24.3   290   31   16   6.2   3.4   16.0  60.8     6.9      M    M
 15000   -3.4  25.9   290   30   15   5.9   3.2   15.4  59.7     6.4      M    M
 14500   -2.1  28.2   290   28   14   5.4   3.0   14.5  58.0     5.6      M    M
 14000   -1.3  29.7   290   27   14   5.9   3.2   13.8  56.8     5.0      M    M
 13500   -0.4  31.3   290   26   13   5.6   3.1   13.2  55.7     4.4      M    M
 13000    0.3  32.5   290   25   13   5.3   2.9   12.5  54.4     3.7      M    M
 12500    1.1  34.0   290   24   12   5.1   2.8   11.8  53.2     3.1      M    M
 12000    1.7  35.1   290   23   12   3.1   1.7   10.9  51.6     2.3      M    M
 11750    2.0  35.6   285   23   12   2.7   1.5   10.4  50.6     1.7      M    M
 11500    2.1  35.8   285   23   12   2.2   1.2    9.8  49.6     1.2      M    M
 11250    2.3  36.1   285   23   12   0.6   0.3    9.2  48.5     0.6      M    M
 11000    2.3  36.1   285   22   11  -0.1  -0.1    8.4  47.2    -0.1    267  1.4
 10750    2.3  36.1   280   22   11  -0.3  -0.1    7.7  45.8    -0.9    260  1.3
 10500    2.1  35.8   280   21   11  -3.1  -1.7    6.8  44.3    -1.7    256  1.3
 10250    1.7  35.1   275   20   10  -7.5  -4.1    5.7  42.2    -2.9    262  1.3
 10000    1.0  33.8   270   19   10 -10.6  -5.8    4.2  39.6    -4.3    276  1.4
  9750    0.3  32.5   265   18    9  -5.7  -3.2    2.8  37.0    -5.8    290  1.5
  9500   -0.3  31.5   260   16    8 -15.2  -8.3    1.5  34.8    -7.1    299  1.5
  9250   -2.6  27.3   255   12    6 -48.4 -26.5   -1.6  29.2   -10.2    362  1.8
  9000   -6.1  21.0   240    7    4 -23.6 -12.9   -5.7  21.7   -14.4    459  2.3
  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 * * * * * *

           11/21/2024 at 0800 MST          |       11/21/2024 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.2        | CAPE...     0.0    LI...       +1.9
CINH...     0.0    K Index...  -0.7        | CINH...     0.0    K Index...  +0.7
                                           |
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 -66.6 -87.9  290  64 33  -1.0  -0.6 | -66.0 -86.8  290  64 33  -0.3  -0.2
 45000 -67.4 -89.3  285  72 37   3.5   1.9 | -66.0 -86.8  285  70 36   2.6   1.4
 40000 -62.1 -79.8  285  56 29   3.3   1.8 | -62.0 -79.6  285  54 28   2.1   1.1
 38000 -57.9 -72.2  285  56 29   7.4   4.1 | -57.9 -72.2  285  53 27   7.3   4.0
 36000 -53.4 -64.1  285  57 29   7.4   4.1 | -53.6 -64.5  285  53 27   7.3   4.0
 34000 -48.5 -55.3  285  56 29   8.9   4.9 | -48.9 -56.0  285  53 27   8.3   4.5
 32000 -43.2 -45.8  290  55 28   8.9   4.9 | -43.3 -45.9  285  55 28   8.3   4.5
 30000 -37.5 -35.5  285  50 26   8.0   4.4 | -38.1 -36.6  285  55 28   8.9   4.9
 29000 -35.1 -31.2  285  48 25   8.1   4.4 | -35.4 -31.7  285  53 28   8.9   4.9
 28000 -32.7 -26.9  285  45 23   8.2   4.5 | -32.7 -26.9  285  52 27   9.1   5.0
 27000 -30.5 -22.9  285  42 22   7.1   3.9 | -30.4 -22.7  285  50 26   7.3   4.0
 26000 -28.3 -18.9  285  39 20   7.1   3.9 | -28.2 -18.8  285  46 24   7.3   4.0
 25000 -26.2 -15.2  290  37 19   7.1   3.9 | -26.0 -14.8  285  43 22   7.4   4.0
 24000 -24.0 -11.2  290  35 18   7.4   4.0 | -23.8 -10.8  290  40 21   7.5   4.1
 23000 -21.9  -7.4  290  35 18   7.4   4.1 | -21.5  -6.7  290  37 19   7.6   4.1
 22000 -19.7  -3.5  290  35 18   7.4   4.0 | -19.3  -2.7  295  35 18   7.6   4.2
 21000 -17.3   0.9  290  34 17   8.3   4.6 | -17.0   1.4  295  34 17   7.8   4.3
 20000 -14.8   5.4  290  33 17   8.4   4.6 | -14.7   5.5  295  33 17   7.8   4.3
 19500 -13.6   7.5  290  32 16   8.3   4.6 | -13.5   7.7  295  33 17   7.8   4.3
 19000 -12.3   9.9  290  31 16   8.1   4.5 | -12.3   9.9  295  33 17   7.7   4.2
 18500 -11.1  12.0  290  30 15   7.9   4.4 | -11.2  11.8  295  32 16   7.7   4.2
 18000 -10.0  14.0  295  29 15   8.0   4.4 | -10.1  13.8  295  30 16   7.7   4.2
 17500  -8.8  16.2  295  27 14   7.1   3.9 |  -8.9  16.0  295  28 15   7.7   4.2
 17000  -7.8  18.0  295  26 13   7.2   4.0 |  -7.8  18.0  295  26 14   7.7   4.2
 16500  -6.7  19.9  300  25 13   7.1   3.9 |  -6.6  20.1  295  24 12   7.7   4.2
 16000  -5.6  21.9  300  24 12   7.0   3.9 |  -5.5  22.1  295  21 11   7.7   4.2
 15500  -4.0  24.8  305  23 12   6.9   3.8 |  -4.3  24.3  295  19 10   7.6   4.1
 15000  -3.0  26.6  305  22 11   6.9   3.8 |  -2.7  27.1  295  16  8   7.2   3.9
 14500  -2.0  28.4  305  21 11   6.1   3.4 |  -1.7  28.9  295  14  7   5.9   3.2
 14000  -1.1  30.0  305  20 10   6.6   3.6 |  -0.7  30.7  295  13  7   7.5   4.1
 13500  -0.1  31.8  305  19 10   6.1   3.3 |   0.4  32.7  295  12  6   6.9   3.8
 13000   0.7  33.3  300  18  9   5.2   2.8 |   1.4  34.5  295  12  6   6.1   3.4
 12500   1.5  34.7  300  18  9   4.9   2.7 |   2.3  36.1  290  11  6   5.7   3.1
 12000   2.1  35.8  295  17  9   3.3   1.8 |   3.0  37.4  285  12  6   4.1   2.3
 11750   2.4  36.3  295  18  9   2.9   1.6 |   3.3  37.9  285  12  6   4.3   2.4
 11500   2.6  36.7  290  18  9   2.4   1.3 |   3.7  38.7  285  12  6   3.2   1.8
 11250   2.7  36.9  290  18  9   1.7   0.9 |   3.8  38.8  280  12  6   0.5   0.3
 11000   2.8  37.0  285  18  9   1.2   0.6 |   3.8  38.8  275  13  7  -0.3  -0.1
 10750   2.9  37.2  280  18  9   1.7   1.0 |   3.8  38.8  275  14  7  -0.7  -0.4
 10500   3.0  37.4  280  18  9  -1.3  -0.7 |   3.7  38.7  270  14  7  -2.1  -1.1
 10250   2.7  36.9  275  17  9  -7.2  -3.9 |   3.5  38.3  270  14  7  -2.8  -1.5
 10000   2.0  35.6  275  17  9 -10.7  -5.9 |   3.2  37.8  265  14  7  -2.6  -1.4
  9750   1.3  34.3  270  16  8  -4.7  -2.6 |   3.0  37.4  255  13  7  -3.9  -2.1
  9500   0.9  33.6  265  16  8 -10.9  -6.0 |   2.8  37.0  250  12  6   3.3   1.8
  9250  -1.1  30.0  260  12  6 -41.7 -22.9 |   3.6  38.5  245  10  5  20.3  11.1
  9000  -4.1  24.6  245   7  4 -17.0  -9.3 |   4.7  40.5  235   8  4  -3.5  -1.9
  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

           11/21/2024 at 1400 MST          |       11/21/2024 at 1700 MST
                                           |
CAPE...     0.0    LI...       +1.7        | CAPE...     0.0    LI...       +1.5
CINH...     0.0    K Index...  -0.5        | CINH...     0.0    K Index...  -4.5
                                           |
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 -65.8 -86.4  290  65 33   1.2   0.6 | -67.7 -89.9  290  63 33   1.0   0.6
 45000 -64.0 -83.2  290  70 36   1.6   0.9 | -65.8 -86.4  290  70 36   2.8   1.6
 40000 -61.5 -78.7  290  55 28   2.6   1.5 | -61.5 -78.7  295  53 28   2.7   1.5
 38000 -57.2 -71.0  285  53 27   7.5   4.1 | -57.0 -70.6  295  51 26   7.9   4.3
 36000 -52.8 -63.0  285  51 26   7.5   4.1 | -52.3 -62.1  290  49 25   7.9   4.3
 34000 -48.1 -54.6  285  50 26   8.0   4.4 | -47.7 -53.9  290  49 25   7.5   4.1
 32000 -43.3 -45.9  285  51 26   8.0   4.4 | -42.6 -44.7  285  49 25   7.5   4.1
 30000 -38.4 -37.1  285  51 27   8.4   4.6 | -37.9 -36.2  285  49 25   8.0   4.4
 29000 -35.9 -32.6  285  52 27   8.4   4.6 | -35.5 -31.9  285  49 25   8.0   4.4
 28000 -33.4 -28.1  285  52 27   8.4   4.6 | -33.1 -27.6  290  48 25   8.0   4.4
 27000 -30.4 -22.7  285  50 26   7.6   4.2 | -30.6 -23.1  290  47 24   8.3   4.6
 26000 -28.1 -18.6  290  47 24   7.6   4.2 | -28.1 -18.6  290  45 23   8.3   4.6
 25000 -25.9 -14.6  290  44 23   7.6   4.2 | -25.6 -14.1  290  42 22   8.3   4.6
 24000 -23.6 -10.5  290  42 21   7.5   4.1 | -23.3  -9.9  290  39 20   7.3   4.0
 23000 -21.4  -6.5  290  38 20   7.5   4.1 | -21.1  -6.0  290  36 18   7.3   4.0
 22000 -19.2  -2.6  295  35 18   7.4   4.1 | -18.9  -2.0  295  32 16   7.2   4.0
 21000 -16.9   1.6  295  34 17   7.9   4.4 | -16.7   1.9  295  30 15   7.8   4.3
 20000 -14.5   5.9  295  33 17   8.0   4.4 | -14.3   6.3  295  29 15   7.8   4.3
 19500 -13.3   8.1  295  33 17   8.0   4.4 | -13.2   8.2  295  28 14   7.9   4.3
 19000 -12.2  10.0  295  32 17   8.0   4.4 | -12.0  10.4  295  27 14   8.0   4.4
 18500 -11.0  12.2  295  32 16   7.9   4.4 | -10.8  12.6  295  27 14   8.1   4.5
 18000  -9.8  14.4  295  31 16   8.0   4.4 |  -9.6  14.7  300  27 14   8.2   4.5
 17500  -8.7  16.3  295  30 15   7.6   4.2 |  -8.4  16.9  300  27 14   7.8   4.3
 17000  -7.6  18.3  295  29 15   7.6   4.2 |  -7.2  19.0  300  26 14   7.8   4.3
 16500  -6.4  20.5  295  27 14   7.4   4.1 |  -6.1  21.0  300  26 13   7.9   4.4
 16000  -5.4  22.3  295  25 13   7.3   4.0 |  -4.9  23.2  300  25 13   8.0   4.4
 15500  -4.3  24.3  295  23 12   7.3   4.0 |  -3.7  25.3  300  24 13   7.8   4.3
 15000  -3.2  26.2  290  21 11   7.5   4.1 |  -2.0  28.4  300  23 12   7.1   3.9
 14500  -2.0  28.4  290  19 10   7.3   4.0 |  -1.0  30.2  295  23 12   6.2   3.4
 14000  -0.5  31.1  285  17  9   6.9   3.8 |  -0.1  31.8  295  22 11   6.7   3.7
 13500   0.5  32.9  285  16  8   6.6   3.6 |   0.9  33.6  295  21 11   6.1   3.4
 13000   1.4  34.5  285  16  8   5.6   3.1 |   1.7  35.1  290  21 11   5.2   2.8
 12500   2.2  36.0  280  16  8   5.4   3.0 |   2.5  36.5  285  21 11   5.1   2.8
 12000   3.0  37.4  280  17  9   4.5   2.5 |   3.2  37.8  285  21 11   4.2   2.3
 11750   3.3  37.9  280  18  9   4.1   2.3 |   3.6  38.5  280  22 11   4.1   2.3
 11500   3.6  38.5  280  18  9   3.6   2.0 |   3.9  39.0  280  22 11   3.8   2.1
 11250   3.8  38.8  280  18  9   2.2   1.2 |   4.1  39.4  280  22 11   2.9   1.6
 11000   4.0  39.2  280  18  9   1.6   0.9 |   4.3  39.7  280  22 11   2.4   1.3
 10750   4.1  39.4  280  18  9   1.7   0.9 |   4.5  40.1  280  21 11   2.6   1.4
 10500   4.2  39.6  275  17  9   2.0   1.1 |   4.7  40.5  280  21 11   1.1   0.6
 10250   4.4  39.9  275  16  8   3.0   1.7 |   4.6  40.3  280  20 10  -2.0  -1.1
 10000   4.6  40.3  270  14  7   3.4   1.9 |   4.4  39.9  275  19 10  -3.8  -2.1
  9750   4.8  40.6  265  13  7   3.4   1.9 |   4.1  39.4  275  17  9  -0.8  -0.5
  9500   5.1  41.2  255  11  6   8.0   4.4 |   3.9  39.0  270  15  8  -5.4  -3.0
  9250   6.0  42.8  250   9  5  15.8   8.6 |   2.8  37.0  260  11  6 -23.3 -12.8
  9000   6.9  44.4  240   7  4   5.2   2.8 |   1.1  34.0  235   7  3 -11.1  -6.1
  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
________________________________________________________________________________

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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