Soaring Guidance
Issued by NWS Pueblo, CO

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205
UXUS97 KPUB 071225
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0625 MDT Friday, June 7, 2024

This forecast is for Villa Grove, CO for Friday, June 7, 2024:

If the trigger temperature of 70.5 F/21.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1438 ft/min (7.3 m/s)
   Maximum height of thermals.................. 23257 ft MSL (14270 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 0930 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 20006 ft MSL (11020 ft AGL)
Thermal soaring outlook for Saturday 06/08..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:40:03 / 20:25:11 MDT
Total possible sunshine........... 14 hr 45 min 8 sec (885 min 8 sec)
Altitude of sun at 13:02:37 MDT... 74.57 degrees

Upper air data from numerical model forecast valid on 06/07/2024 at 0600 MDT

Freezing level.................. 16671 ft MSL (7684 ft AGL)
Convective condensation level... 19384 ft MSL (10397 ft AGL)
Lifted condensation level....... 20970 ft MSL (11983 ft AGL)
Lifted index.................... -2.5
K index......................... +12.5

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  -63.3 -81.9   260   19   10  -0.2  -0.1      M     M       M      M    M
 45000  -61.5 -78.7   255   21   11   4.6   2.5      M     M       M      M    M
 40000  -54.1 -65.4   235   31   16   7.4   4.1      M     M       M      M    M
 38000  -49.6 -57.3   235   31   16   7.5   4.1      M     M       M      M    M
 36000  -45.1 -49.2   230   31   16   7.5   4.1      M     M       M      M    M
 34000  -39.9 -39.8   235   27   14   7.8   4.3      M     M       M      M    M
 32000  -35.2 -31.4   245   23   12   8.0   4.4      M     M       M      M    M
 30000  -30.2 -22.4   250   22   12   8.4   4.6   33.7  92.6     4.7      M    M
 29000  -27.7 -17.9   250   22   11   8.4   4.6   33.2  91.8     4.4      M    M
 28000  -25.2 -13.4   255   22   11   7.7   4.2   32.8  91.0     4.1      M    M
 27000  -22.9  -9.2   260   21   11   7.6   4.2   31.9  89.4     3.4      M    M
 26000  -20.6  -5.1   260   21   11   7.6   4.2   31.1  88.0     2.8      M    M
 25000  -18.3  -0.9   260   21   11   7.2   4.0   30.4  86.8     2.2      M    M
 24000  -16.6   2.1   265   23   12   5.7   3.1   29.0  84.2     1.0      M    M
 23000  -14.9   5.2   265   25   13   5.7   3.1   27.6  81.6    -0.3   1421  7.2
 22000  -13.2   8.2   265   28   14   6.4   3.5   26.3  79.3    -1.4   1341  6.8
 21000  -11.0  12.2   265   29   15   7.7   4.2   25.4  77.7    -2.2   1245  6.3
 20000   -8.7  16.3   265   29   15   7.7   4.2   24.7  76.5    -2.9   1148  5.8
 19500   -7.6  18.3   265   30   15   7.6   4.2   24.4  75.9    -3.3   1099  5.6
 19000   -6.4  20.5   265   30   15   8.4   4.6   24.1  75.4    -3.6   1049  5.3
 18500   -5.2  22.6   260   30   15   8.4   4.6   23.9  75.0    -3.8    998  5.1
 18000   -4.0  24.8   260   30   16   8.8   4.8   23.7  74.6    -4.1    946  4.8
 17500   -2.6  27.3   260   29   15   9.4   5.2   23.6  74.5    -4.2    891  4.5
 17000   -0.6  30.9   255   28   14   9.3   5.1   23.5  74.3    -4.4    807  4.1
 16500    0.8  33.4   260   27   14   9.2   5.1   23.4  74.2    -4.5    751  3.8
 16000    2.2  36.0   260   27   14   9.2   5.1   23.3  74.0    -4.6    695  3.5
 15500    3.5  38.3   260   26   13   8.3   4.6   23.2  73.7    -4.8    641  3.3
 15000    4.7  40.5   265   25   13   8.3   4.6   23.0  73.3    -5.1    589  3.0
 14500    6.0  42.8   270   24   12   8.4   4.6   22.8  73.0    -5.3    537  2.7
 14000    7.2  45.0   275   23   12   8.0   4.4   22.5  72.5    -5.6    486  2.5
 13500    8.3  46.9   280   22   11   7.7   4.2   22.2  72.0    -5.9    436  2.2
 13000    9.6  49.3   280   21   11   9.4   5.2   22.0  71.7    -6.2    384  1.9
 12500   11.0  51.8   280   19   10   9.0   4.9   22.0  71.5    -6.3    328  1.7
 12000   12.2  54.0   280   18    9   9.4   5.1   21.8  71.2    -6.5    275  1.4
 11750   13.0  55.4   280   17    9  10.8   5.9   21.8  71.3    -6.5    244  1.2
 11500   13.8  56.8   280   16    8   9.2   5.0   21.9  71.3    -6.4    213  1.1
 11250   14.3  57.7   280   16    8   6.3   3.5   21.7  71.1    -6.6    189  1.0
 11000   14.7  58.5   280   15    8   5.3   2.9   21.4  70.5    -7.0    170  0.9
 10750   15.1  59.2   275   15    8   6.0   3.3   21.1  69.9    -7.4    151  0.8
 10500   15.5  59.9   270   14    7   3.5   1.9   20.7  69.3    -7.8    134  0.7
 10250   15.4  59.7   270   14    7  -3.1  -1.7   20.0  68.0    -8.6    128  0.7
 10000   14.9  58.8   260   12    6  -6.4  -3.5   18.8  65.9    -9.9    136  0.7
  9750   14.4  57.9   255   11    6  -3.2  -1.7   17.7  63.9   -11.2    145  0.7
  9500   14.0  57.2   245   10    5  -7.0  -3.8   16.7  62.1   -12.3    149  0.8
  9250   12.8  55.0   235    8    4 -24.9 -13.6   14.8  58.7   -14.3    178  0.9
  9000   10.6  51.1   240    5    2 -27.5 -15.1   11.9  53.4   -17.2    235  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 * * * * * *

           06/07/2024 at 0900 MDT          |       06/07/2024 at 1200 MDT
                                           |
CAPE...  +442.7    LI...       -0.3        | CAPE...  +448.4    LI...       -1.0
CINH...   -87.0    K Index... +10.7        | CINH...    -0.4    K Index... +21.0
                                           |
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 -63.0 -81.4  270  19 10  -0.3  -0.1 | -62.8 -81.0  260  16  8  -0.2  -0.1
 45000 -61.4 -78.5  265  20 10   4.7   2.6 | -61.1 -78.0  245  18  9   4.7   2.6
 40000 -53.6 -64.5  250  28 15   6.6   3.6 | -53.4 -64.1  250  28 15   6.3   3.5
 38000 -49.7 -57.5  250  28 14   6.6   3.6 | -49.7 -57.5  255  29 15   6.3   3.5
 36000 -45.7 -50.3  245  28 14   6.6   3.6 | -45.9 -50.6  255  29 15   6.3   3.4
 34000 -40.9 -41.6  245  26 14   8.2   4.5 | -41.2 -42.2  250  29 15   8.0   4.4
 32000 -36.0 -32.8  240  25 13   8.2   4.5 | -36.4 -33.5  250  29 15   8.0   4.4
 30000 -31.0 -23.8  240  24 12   8.4   4.6 | -31.5 -24.7  245  27 14   8.1   4.4
 29000 -28.5 -19.3  240  23 12   8.4   4.6 | -29.1 -20.4  245  26 13   8.1   4.5
 28000 -25.4 -13.7  240  22 12   7.0   3.8 | -26.1 -15.0  245  24 12   7.0   3.8
 27000 -23.3  -9.9  245  23 12   7.2   3.9 | -24.0 -11.2  255  25 13   7.1   3.9
 26000 -21.2  -6.2  250  25 13   7.2   3.9 | -21.9  -7.4  260  26 13   7.1   3.9
 25000 -19.0  -2.2  255  26 13   6.6   3.6 | -19.8  -3.6  265  27 14   6.8   3.7
 24000 -17.3   0.9  260  28 14   5.7   3.2 | -17.9  -0.2  270  28 14   6.3   3.5
 23000 -15.7   3.7  260  30 15   5.8   3.2 | -16.1   3.0  275  29 15   6.4   3.5
 22000 -14.0   6.8  265  32 16   7.4   4.0 | -14.2   6.4  275  29 15   7.6   4.2
 21000 -11.4  11.5  270  26 13   8.7   4.8 | -11.7  10.9  275  25 13   8.6   4.7
 20000  -8.8  16.2  275  20 10   8.7   4.8 |  -9.2  15.4  270  22 11   8.7   4.8
 19500  -7.5  18.5  280  17  9   8.7   4.8 |  -7.9  17.8  265  20 10   8.7   4.8
 19000  -6.2  20.8  280  16  8   9.1   5.0 |  -6.6  20.1  265  19 10   9.3   5.1
 18500  -4.9  23.2  285  16  8   9.0   5.0 |  -5.3  22.5  265  18  9   9.3   5.1
 18000  -3.5  25.7  290  16  8   8.8   4.8 |  -3.9  25.0  265  17  9   9.2   5.1
 17500  -2.2  28.0  290  16  8   8.6   4.7 |  -2.6  27.3  270  17  9   9.2   5.0
 17000  -1.0  30.2  290  16  8   8.6   4.7 |  -1.3  29.7  270  17  9   9.2   5.1
 16500   0.3  32.5  290  17  9   8.4   4.6 |   0.1  32.2  270  17  9   9.8   5.4
 16000   1.5  34.7  290  17  9   8.4   4.6 |   1.6  34.9  270  17  9   9.8   5.4
 15500   2.8  37.0  285  18  9   8.6   4.7 |   3.0  37.4  270  17  9   9.8   5.4
 15000   4.0  39.2  285  18  9   8.6   4.7 |   4.4  39.9  270  16  8   9.7   5.3
 14500   6.0  42.8  285  19 10   9.4   5.2 |   6.5  43.7  270  16  8   9.0   4.9
 14000   7.3  45.1  285  20 10   9.0   5.0 |   7.9  46.2  270  16  8   9.5   5.2
 13500   8.6  47.5  285  21 11   9.6   5.3 |   9.3  48.7  270  15  8   9.5   5.2
 13000  10.0  50.0  280  21 11   8.6   4.7 |  10.8  51.4  265  15  8  10.3   5.7
 12500  11.3  52.3  275  21 11   8.4   4.6 |  12.4  54.3  265  15  8   9.3   5.1
 12000  12.4  54.3  275  20 10   7.8   4.3 |  13.6  56.5  265  14  7   9.9   5.4
 11750  13.0  55.4  275  20 10   7.7   4.2 |  14.4  57.9  265  14  7  10.8   5.9
 11500  13.6  56.5  270  19 10   7.2   4.0 |  15.2  59.4  265  14  7  10.2   5.6
 11250  14.0  57.2  270  18  9   6.3   3.5 |  16.0  60.8  265  14  7   9.7   5.3
 11000  14.5  58.1  270  17  9   6.3   3.4 |  16.7  62.1  265  14  7   9.7   5.3
 10750  14.9  58.8  265  17  9   6.4   3.5 |  17.4  63.3  265  13  7  10.7   5.9
 10500  15.3  59.5  260  16  8   5.6   3.1 |  18.2  64.8  260  13  7  11.1   6.1
 10250  15.6  60.1  260  15  8   4.2   2.3 |  19.0  66.2  260  13  7  10.6   5.8
 10000  15.8  60.4  255  13  7   4.3   2.4 |  19.8  67.6  260  13  7  10.8   5.9
  9750  16.0  60.8  250  12  6   3.7   2.0 |  20.6  69.1  260  12  6   9.9   5.5
  9500  16.3  61.3  240  11  6   9.1   5.0 |  21.5  70.7  260  12  6  15.6   8.5
  9250  17.4  63.3  235   9  5  22.5  12.3 |  23.1  73.6  260  11  6  30.1  16.5
  9000  18.9  66.0  230   8  4  11.2   6.1 |  25.3  77.5  255  10  5  22.4  12.3
  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

           06/07/2024 at 1500 MDT          |       06/07/2024 at 1800 MDT
                                           |
CAPE...  +438.3    LI...       -0.8        | CAPE...  +118.4    LI...       -0.1
CINH...   -19.7    K Index... +26.6        | CINH...  -142.6    K Index... +22.1
                                           |
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 -62.6 -80.7  255  16  8  -0.5  -0.3 | -62.3 -80.1  255  19 10  -1.0  -0.6
 45000 -61.2 -78.2  240  19 10   4.5   2.5 | -61.7 -79.1  235  21 11   4.1   2.2
 40000 -53.7 -64.7  245  26 14   6.8   3.7 | -54.7 -66.5  225  27 14   7.5   4.1
 38000 -49.6 -57.3  245  30 15   6.8   3.7 | -50.2 -58.4  235  28 14   7.5   4.1
 36000 -45.5 -49.9  245  33 17   6.8   3.7 | -45.7 -50.3  240  29 15   7.5   4.1
 34000 -40.5 -40.9  250  33 17   8.6   4.7 | -40.4 -40.7  250  29 15   8.9   4.9
 32000 -35.3 -31.5  250  32 16   8.6   4.7 | -35.1 -31.2  255  30 16   8.8   4.8
 30000 -30.8 -23.4  255  30 15   7.3   4.0 | -30.2 -22.4  260  30 16   8.1   4.5
 29000 -28.7 -19.7  260  29 15   7.3   4.0 | -27.8 -18.0  260  31 16   8.2   4.5
 28000 -26.1 -15.0  265  27 14   5.7   3.1 | -24.9 -12.8  265  31 16   6.3   3.4
 27000 -24.4 -11.9  270  26 13   5.8   3.2 | -23.0  -9.4  265  30 15   6.4   3.5
 26000 -22.6  -8.7  275  25 13   5.9   3.2 | -21.1  -6.0  270  29 15   6.4   3.5
 25000 -20.9  -5.6  285  25 13   6.9   3.8 | -19.2  -2.6  275  29 15   6.5   3.5
 24000 -18.5  -1.3  285  23 12   8.3   4.5 | -17.3   0.9  280  28 15   6.5   3.6
 23000 -16.1   3.0  290  22 11   8.3   4.6 | -15.3   4.5  280  27 14   6.6   3.6
 22000 -13.7   7.3  295  20 11   8.5   4.7 | -13.4   7.9  285  27 14   7.6   4.2
 21000 -11.2  11.8  290  19 10   8.6   4.7 | -10.8  12.6  290  25 13   8.7   4.8
 20000  -8.7  16.3  290  18  9   8.7   4.7 |  -8.3  17.1  290  23 12   8.8   4.8
 19500  -7.4  18.7  290  17  9   8.7   4.8 |  -7.0  19.4  295  22 11   8.8   4.8
 19000  -6.1  21.0  290  17  9   9.7   5.3 |  -5.7  21.7  295  20 10   9.1   5.0
 18500  -4.6  23.7  285  16  8   9.7   5.3 |  -4.4  24.1  295  18  9   9.1   5.0
 18000  -3.2  26.2  285  16  8   9.5   5.2 |  -3.1  26.4  295  16  8   9.0   4.9
 17500  -1.8  28.8  285  16  8   9.5   5.2 |  -1.8  28.8  295  14  7   8.9   4.9
 17000  -0.4  31.3  280  16  8   9.4   5.2 |  -0.5  31.1  295  12  6   8.8   4.8
 16500   1.0  33.8  280  15  8   9.6   5.2 |   0.8  33.4  295  11  6   9.3   5.1
 16000   2.4  36.3  275  15  8   9.6   5.2 |   2.2  36.0  290  10  5   9.3   5.1
 15500   3.8  38.8  275  15  8   9.4   5.1 |   3.6  38.5  290  10  5   9.2   5.0
 15000   5.2  41.4  270  15  8   9.3   5.1 |   4.9  40.8  285   9  5   9.1   5.0
 14500   7.2  45.0  265  15  8   8.4   4.6 |   6.9  44.4  270   9  5   8.3   4.5
 14000   8.5  47.3  260  15  8   8.4   4.6 |   8.2  46.8  265  10  5   8.5   4.6
 13500   9.7  49.5  255  15  8   8.8   4.8 |   9.4  48.9  255  10  5   7.6   4.2
 13000  11.0  51.8  250  16  8   8.7   4.8 |  10.5  50.9  245  11  6   7.8   4.3
 12500  12.3  54.1  250  16  8   8.4   4.6 |  11.7  53.1  240  13  7   7.1   3.9
 12000  13.5  56.3  245  17  9   9.0   5.0 |  12.6  54.7  235  15  8   6.2   3.4
 11750  14.3  57.7  240  17  9   9.7   5.3 |  13.1  55.6  230  16  8   6.6   3.6
 11500  15.0  59.0  240  17  9   9.3   5.1 |  13.5  56.3  230  17  9   6.3   3.5
 11250  15.6  60.1  240  18  9   8.9   4.9 |  14.0  57.2  230  18  9   5.7   3.1
 11000  16.3  61.3  240  18  9   8.8   4.8 |  14.4  57.9  225  19 10   5.4   3.0
 10750  16.9  62.4  235  18  9   9.8   5.4 |  14.8  58.6  225  20 10   5.7   3.1
 10500  17.7  63.9  235  18  9  10.3   5.7 |  15.2  59.4  225  20 10   5.6   3.1
 10250  18.4  65.1  235  18  9  10.0   5.5 |  15.5  59.9  225  20 10   4.8   2.6
 10000  19.2  66.6  235  17  9  10.2   5.6 |  15.8  60.4  225  20 10   4.5   2.4
  9750  19.9  67.8  235  17  9   9.7   5.3 |  16.1  61.0  225  19 10   4.3   2.3
  9500  20.7  69.3  235  17  9  12.8   7.0 |  16.4  61.5  225  19 10   6.8   3.7
  9250  21.9  71.4  235  16  8  21.8  12.0 |  17.1  62.8  225  16  8  14.6   8.0
  9000  23.7  74.7  235  13  7  24.0  13.1 |  18.4  65.1  225  12  6  17.9   9.8
  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
________________________________________________________________________________

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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