Soaring Guidance
Issued by NWS Pueblo, CO

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319
UXUS97 KPUB 151229
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0629 MDT Saturday, June 15, 2024

This forecast is for Villa Grove, CO for Saturday, June 15, 2024:

If the trigger temperature of 63.2 F/17.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1387 ft/min (7.0 m/s)
   Maximum height of thermals.................. 23594 ft MSL (14611 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 0930 MDT
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................. 21153 ft MSL (12170 ft AGL)
Thermal soaring outlook for Sunday 06/16....... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:39:41 / 20:28:50 MDT
Total possible sunshine........... 14 hr 49 min 9 sec (889 min 9 sec)
Altitude of sun at 13:04:16 MDT... 75.05 degrees

Upper air data from numerical model forecast valid on 06/15/2024 at 0600 MDT

Freezing level.................. 15085 ft MSL (6102 ft AGL)
Convective condensation level... 16843 ft MSL (7860 ft AGL)
Lifted condensation level....... 20056 ft MSL (11073 ft AGL)
Lifted index.................... -4.3
K index......................... +10.3

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  -59.6 -75.3   270   32   17   2.6   1.5      M     M       M      M    M
 45000  -55.1 -67.2   275   40   21   3.3   1.8      M     M       M      M    M
 40000  -50.1 -58.2   280   44   22   3.9   2.1      M     M       M      M    M
 38000  -47.8 -54.0   285   42   22   3.9   2.1      M     M       M      M    M
 36000  -45.5 -49.9   290   41   21   3.9   2.2      M     M       M      M    M
 34000  -41.5 -42.7   290   39   20   7.5   4.1      M     M       M      M    M
 32000  -37.0 -34.6   295   38   20   7.5   4.1      M     M       M      M    M
 30000  -31.5 -24.7   295   34   18   8.3   4.6   32.5  90.5     4.2      M    M
 29000  -29.0 -20.2   295   33   17   8.3   4.6   32.0  89.6     3.9      M    M
 28000  -26.5 -15.7   295   31   16   8.0   4.4   31.7  89.0     3.6      M    M
 27000  -24.2 -11.6   295   30   15   7.6   4.2   30.7  87.3     2.9      M    M
 26000  -21.9  -7.4   295   29   15   7.6   4.2   29.9  85.9     2.3      M    M
 25000  -19.7  -3.5   300   27   14   7.9   4.3   29.3  84.7     1.7      M    M
 24000  -17.9  -0.2   305   26   13   5.4   3.0   27.9  82.2     0.6      M    M
 23000  -16.3   2.7   310   24   12   5.5   3.0   26.3  79.4    -0.8   1341  6.8
 22000  -14.7   5.5   315   22   11   5.7   3.1   25.0  77.0    -2.0   1263  6.4
 21000  -12.7   9.1   320   21   11   6.9   3.8   23.9  74.9    -3.1   1175  6.0
 20000  -10.7  12.7   320   21   11   6.9   3.8   22.9  73.2    -4.1   1085  5.5
 19500   -9.7  14.5   320   21   11   6.9   3.8   22.4  72.4    -4.5   1040  5.3
 19000   -8.7  16.3   320   20   10   6.9   3.8   22.0  71.6    -4.9    995  5.1
 18500   -7.7  18.1   320   20   10   6.9   3.8   21.5  70.7    -5.4    949  4.8
 18000   -6.6  20.1   320   19   10   6.9   3.8   21.1  69.9    -5.9    904  4.6
 17500   -5.7  21.7   325   18    9   6.4   3.5   20.5  69.0    -6.4    860  4.4
 17000   -4.7  23.5   325   17    9   6.4   3.5   20.0  68.0    -7.0    816  4.1
 16500   -3.7  25.3   325   16    8   7.6   4.2   19.5  67.2    -7.4    772  3.9
 16000   -2.5  27.5   330   15    8   7.8   4.3   19.2  66.6    -7.8    722  3.7
 15500   -0.8  30.6   330   14    7   8.6   4.7   18.8  65.9    -8.3    647  3.3
 15000    0.5  32.9   335   14    7   8.8   4.8   18.6  65.5    -8.5    594  3.0
 14500    1.7  35.1   335   13    7   8.1   4.4   18.4  65.1    -8.8    543  2.8
 14000    3.0  37.4   335   13    7   8.7   4.8   18.2  64.8    -9.1    490  2.5
 13500    4.3  39.7   335   13    7   8.8   4.8   18.1  64.5    -9.3    437  2.2
 13000    5.6  42.1   335   14    7   9.2   5.1   18.0  64.3    -9.5    383  1.9
 12500    6.9  44.4   330   15    8   8.7   4.8   17.9  64.2    -9.7    329  1.7
 12000    7.9  46.2   325   16    8   7.5   4.1   17.5  63.5   -10.2    284  1.4
 11750    8.5  47.3   325   16    8   9.2   5.0   17.4  63.3   -10.4    259  1.3
 11500    9.1  48.4   320   16    8   8.4   4.6   17.3  63.2   -10.5    233  1.2
 11250    9.6  49.3   320   16    8   6.1   3.4   17.2  62.9   -10.8    210  1.1
 11000    9.9  49.8   315   16    8   5.0   2.8   16.8  62.3   -11.2    193  1.0
 10750   10.3  50.5   310   16    8   5.2   2.8   16.5  61.6   -11.6    175  0.9
 10500   10.5  50.9   300   16    8   3.8   2.1   16.1  60.9   -12.1    160  0.8
 10250   10.6  51.1   295   15    8  -0.4  -0.2   15.5  59.9   -12.8    149  0.8
 10000   10.4  50.7   290   15    8  -3.3  -1.8   14.6  58.2   -13.7    148  0.8
  9750   10.2  50.4   285   14    7  -1.1  -0.6   13.6  56.5   -14.7    147  0.7
  9500   10.0  50.0   280   14    7  -7.3  -4.0   12.7  54.9   -15.7    146  0.7
  9250    8.8  47.8   270   11    6 -27.2 -14.9   10.7  51.3   -17.7    175  0.9
  9000    6.4  43.5   250    6    3 -31.2 -17.1    7.6  45.6   -20.9    240  1.2
  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 * * * * * *

           06/15/2024 at 0900 MDT          |       06/15/2024 at 1200 MDT
                                           |
CAPE...  +340.8    LI...       -2.0        | CAPE...  +408.7    LI...       -2.0
CINH...   -58.2    K Index...  +7.5        | CINH...    -3.8    K Index... +14.7
                                           |
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 -59.9 -75.8  265  33 17   3.5   1.9 | -60.4 -76.7  255  36 18   3.5   1.9
 45000 -54.5 -66.1  265  39 20   3.2   1.7 | -55.1 -67.2  260  42 22   3.1   1.7
 40000 -49.7 -57.5  280  44 23   3.9   2.2 | -50.4 -58.7  270  43 22   4.0   2.2
 38000 -47.3 -53.1  280  41 21   3.9   2.1 | -48.0 -54.4  270  41 21   4.0   2.2
 36000 -45.0 -49.0  280  38 20   4.0   2.2 | -45.6 -50.1  270  40 20   4.0   2.2
 34000 -41.4 -42.5  280  36 19   6.5   3.6 | -41.9 -43.4  275  41 21   6.8   3.7
 32000 -37.5 -35.5  280  35 18   6.6   3.6 | -37.9 -36.2  280  43 22   6.8   3.7
 30000 -32.0 -25.6  280  34 17   8.8   4.8 | -32.5 -26.5  280  41 21   8.4   4.6
 29000 -29.3 -20.7  280  33 17   8.8   4.8 | -30.0 -22.0  280  39 20   8.4   4.6
 28000 -26.7 -16.1  280  33 17   8.4   4.6 | -27.5 -17.5  280  38 20   8.9   4.9
 27000 -24.2 -11.6  285  31 16   8.1   4.4 | -24.7 -12.5  280  36 18   9.3   5.1
 26000 -21.8  -7.2  290  30 15   8.1   4.4 | -21.9  -7.4  280  33 17   9.3   5.1
 25000 -19.4  -2.9  290  28 14   8.5   4.7 | -19.1  -2.4  280  31 16   9.3   5.1
 24000 -17.6   0.3  295  26 13   5.1   2.8 | -17.2   1.0  280  28 14   5.6   3.1
 23000 -16.1   3.0  300  24 12   5.1   2.8 | -15.5   4.1  280  24 13   5.7   3.1
 22000 -14.6   5.7  305  21 11   5.1   2.8 | -13.9   7.0  280  21 11   5.7   3.2
 21000 -12.8   9.0  315  21 11   6.1   3.3 | -12.2  10.0  285  18  9   5.8   3.2
 20000 -11.0  12.2  325  21 11   6.2   3.4 | -10.5  13.1  295  16  8   5.9   3.2
 19500 -10.2  13.6  330  21 11   6.1   3.4 |  -9.6  14.7  305  15  8   5.9   3.2
 19000  -9.2  15.4  330  21 11   7.9   4.4 |  -8.7  16.3  310  14  7   7.3   4.0
 18500  -8.0  17.6  330  22 11   8.3   4.6 |  -7.6  18.3  315  15  7   7.6   4.2
 18000  -6.7  19.9  330  22 11   8.4   4.6 |  -6.6  20.1  315  15  8   7.9   4.3
 17500  -5.5  22.1  330  21 11   8.8   4.8 |  -5.3  22.5  315  15  8   9.0   5.0
 17000  -4.2  24.4  330  20 10   8.8   4.8 |  -4.0  24.8  315  16  8   9.0   4.9
 16500  -2.9  26.8  330  18  9   8.3   4.5 |  -2.7  27.1  310  16  8   9.0   5.0
 16000  -1.7  28.9  330  16  8   8.2   4.5 |  -1.3  29.7  310  15  8   9.1   5.0
 15500   0.1  32.2  330  14  7   7.9   4.3 |   0.0  32.0  305  15  8   9.4   5.2
 15000   1.2  34.2  330  13  7   8.0   4.4 |   2.2  36.0  300  14  7  10.0   5.5
 14500   2.4  36.3  330  11  6   7.8   4.3 |   3.6  38.5  290  13  7   8.6   4.7
 14000   3.5  38.3  330  10  5   8.0   4.4 |   4.9  40.8  285  12  6   9.1   5.0
 13500   4.7  40.5  330   8  4   7.7   4.2 |   6.2  43.2  280  11  6   8.3   4.6
 13000   6.0  42.8  325   8  4   9.6   5.2 |   7.5  45.5  270  10  5  10.1   5.6
 12500   7.4  45.3  325   7  4   8.8   4.9 |   8.9  48.0  265  10  5   9.5   5.2
 12000   8.5  47.3  320   7  4   7.9   4.3 |  10.1  50.2  260   9  5   9.8   5.4
 11750   9.1  48.4  320   7  4   9.6   5.3 |  11.0  51.8  260   9  5  11.5   6.3
 11500   9.8  49.6  320   8  4   8.7   4.8 |  11.8  53.2  260   9  5  10.7   5.8
 11250  10.3  50.5  315   8  4   6.9   3.8 |  12.5  54.5  255   9  5   9.3   5.1
 11000  10.8  51.4  310   8  4   6.2   3.4 |  13.1  55.6  255   9  5   8.6   4.7
 10750  11.2  52.2  305   9  5   6.1   3.4 |  13.8  56.8  255   9  4  10.3   5.6
 10500  11.5  52.7  295  10  5   5.0   2.7 |  14.6  58.3  255   9  4  11.3   6.2
 10250  11.7  53.1  290  10  5   2.5   1.4 |  15.5  59.9  250   8  4  10.7   5.9
 10000  11.7  53.1  280   9  5   1.2   0.7 |  16.2  61.2  250   8  4  10.9   6.0
  9750  11.7  53.1  270   9  5   1.7   0.9 |  17.0  62.6  250   8  4  10.1   5.5
  9500  11.9  53.4  260   9  5   8.2   4.5 |  17.8  64.0  250   8  4  13.3   7.3
  9250  12.9  55.2  250   8  4  21.5  11.8 |  19.2  66.6  245   7  4  26.4  14.5
  9000  14.4  57.9  240   7  4  13.7   7.5 |  21.6  70.9  245   7  4  37.9  20.8
  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

           06/15/2024 at 1500 MDT          |       06/15/2024 at 1800 MDT
                                           |
CAPE...  +523.8    LI...       -1.4        | CAPE...  +752.3    LI...       -2.2
CINH...    -4.1    K Index... +28.8        | CINH...   -63.1    K Index... +27.3
                                           |
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  250  38 20   3.3   1.8 | -59.6 -75.3  260  40 21   3.3   1.8
 45000 -55.1 -67.2  260  51 26   2.8   1.6 | -54.9 -66.8  270  50 26   2.6   1.4
 40000 -50.7 -59.3  260  49 25   3.6   2.0 | -50.7 -59.3  280  44 23   3.5   1.9
 38000 -48.6 -55.5  260  47 24   3.6   2.0 | -48.6 -55.5  270  40 21   3.5   1.9
 36000 -46.4 -51.5  260  46 24   3.6   2.0 | -46.5 -51.7  260  37 19   3.6   1.9
 34000 -42.4 -44.3  260  46 23   7.5   4.1 | -42.5 -44.5  265  35 18   7.6   4.2
 32000 -37.9 -36.2  260  46 24   7.6   4.1 | -37.9 -36.2  270  34 17   7.7   4.2
 30000 -32.6 -26.7  265  41 21   8.0   4.4 | -33.3 -27.9  270  33 17   7.8   4.3
 29000 -30.2 -22.4  270  39 20   8.0   4.4 | -30.4 -22.7  270  32 17   7.8   4.3
 28000 -27.8 -18.0  275  36 19   7.7   4.2 | -28.1 -18.6  270  32 16   7.7   4.2
 27000 -25.6 -14.1  275  35 18   7.5   4.1 | -25.8 -14.4  275  32 16   7.6   4.2
 26000 -23.3  -9.9  280  34 17   7.5   4.1 | -23.5 -10.3  275  32 17   7.6   4.2
 25000 -21.1  -6.0  285  32 17   7.6   4.1 | -21.2  -6.2  280  33 17   7.7   4.2
 24000 -19.1  -2.4  285  30 15   6.6   3.6 | -19.2  -2.6  280  30 15   6.7   3.7
 23000 -17.2   1.0  280  27 14   6.8   3.7 | -17.2   1.0  285  26 13   6.8   3.7
 22000 -15.3   4.5  280  25 13   7.2   3.9 | -15.2   4.6  290  22 11   7.1   3.9
 21000 -12.8   9.0  280  21 11   8.8   4.8 | -12.8   9.0  290  21 11   8.5   4.7
 20000 -10.3  13.5  280  18  9   8.9   4.9 | -10.4  13.3  290  20 11   8.6   4.7
 19500  -9.0  15.8  280  16  8   9.0   4.9 |  -9.2  15.4  290  20 10   8.7   4.8
 19000  -7.7  18.1  280  14  7   8.0   4.4 |  -7.9  17.8  290  20 10   9.0   4.9
 18500  -6.6  20.1  280  14  7   8.0   4.4 |  -6.6  20.1  290  19 10   9.0   4.9
 18000  -5.4  22.3  280  13  7   8.3   4.6 |  -5.3  22.5  290  18  9   9.2   5.0
 17500  -4.1  24.6  275  13  7   9.6   5.2 |  -3.9  25.0  290  18  9   9.8   5.4
 17000  -2.6  27.3  275  13  7   9.5   5.2 |  -2.5  27.5  290  17  9   9.9   5.4
 16500  -1.2  29.8  275  13  7   9.5   5.2 |  -1.0  30.2  285  17  9   9.2   5.1
 16000   0.2  32.4  275  13  7   9.5   5.2 |   0.3  32.5  285  16  8   9.2   5.0
 15500   1.6  34.9  270  13  7   9.7   5.3 |   1.7  35.1  285  16  8   9.4   5.2
 15000   3.8  38.8  265  13  7  10.5   5.8 |   3.9  39.0  280  16  8  10.5   5.7
 14500   5.1  41.2  265  13  7   8.1   4.4 |   5.1  41.2  275  15  8   7.1   3.9
 14000   6.5  43.7  260  13  7   9.3   5.1 |   6.3  43.3  270  15  8   8.5   4.7
 13500   8.0  46.4  260  13  7   8.2   4.5 |   7.6  45.7  265  15  8   7.5   4.1
 13000   9.2  48.6  255  13  7  10.0   5.5 |   8.6  47.5  255  15  8   7.8   4.3
 12500  10.7  51.3  255  13  7   9.3   5.1 |   9.7  49.5  250  15  8   7.3   4.0
 12000  11.9  53.4  250  13  7   9.6   5.3 |  10.5  50.9  240  17  9   5.5   3.0
 11750  12.7  54.9  250  13  7  11.1   6.1 |  11.0  51.8  235  17  9   6.4   3.5
 11500  13.5  56.3  250  13  7  10.6   5.8 |  11.4  52.5  235  18  9   6.1   3.4
 11250  14.3  57.7  250  13  7  10.4   5.5 |  11.8  53.2  230  19 10   6.1   3.4
 11000  15.0  59.0  250  13  7   9.4   5.2 |  12.3  54.1  225  19 10   6.0   3.3
 10750  15.7  60.3  250  13  7   9.8   5.4 |  12.7  54.9  225  20 10   7.3   4.0
 10500  16.5  61.7  245  13  7   9.8   5.4 |  13.3  55.9  220  20 10   8.3   4.5
 10250  17.2  63.0  245  13  7  10.4   5.7 |  13.9  57.0  220  20 10   8.8   4.8
 10000  18.0  64.4  245  13  7  10.9   6.0 |  14.5  58.1  220  19 10   9.6   5.3
  9750  18.8  65.8  245  13  6  10.5   5.8 |  15.2  59.4  215  19 10   9.4   5.1
  9500  19.6  67.3  245  12  6  10.5   5.8 |  16.0  60.8  215  18  9  10.4   5.7
  9250  20.5  68.9  245  11  6  15.9   8.7 |  16.9  62.4  215  17  9  15.9   8.7
  9000  22.3  72.1  245  10  5  38.0  20.8 |  18.6  65.5  215  14  7  33.6  18.4
  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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