Soaring Guidance
Issued by NWS Pueblo, CO

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343
UXUS97 KPUB 241210
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0610 MDT Monday, June 24, 2024

This forecast is for Villa Grove, CO for Monday, June 24, 2024:

If the trigger temperature of 70.7 F/21.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1339 ft/min (6.8 m/s)
   Maximum height of thermals.................. 22514 ft MSL (13544 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 0945 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................. 19196 ft MSL (10226 ft AGL)
Thermal soaring outlook for Tuesday 06/25...... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:41:29 / 20:30:56 MDT
Total possible sunshine........... 14 hr 49 min 26 sec (889 min 26 sec)
Altitude of sun at 13:06:12 MDT... 75.06 degrees

Upper air data from numerical model forecast valid on 06/24/2024 at 0600 MDT

Freezing level.................. 16535 ft MSL (7565 ft AGL)
Convective condensation level... 17111 ft MSL (8141 ft AGL)
Lifted condensation level....... 19343 ft MSL (10373 ft AGL)
Lifted index.................... -4.3
K index......................... +19.3

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  -64.6 -84.3   265   32   17   3.2   1.8      M     M       M      M    M
 45000  -57.6 -71.7   265   43   22   6.3   3.4      M     M       M      M    M
 40000  -48.1 -54.6   265   49   25   6.6   3.6      M     M       M      M    M
 38000  -44.2 -47.6   265   50   26   6.6   3.6      M     M       M      M    M
 36000  -40.3 -40.5   265   51   26   6.7   3.7      M     M       M      M    M
 34000  -36.1 -33.0   265   46   24   6.9   3.8      M     M       M      M    M
 32000  -32.0 -25.6   265   41   21   7.3   4.0      M     M       M      M    M
 30000  -27.5 -17.5   270   33   17   6.7   3.7   36.6  97.9     6.5      M    M
 29000  -25.5 -13.9   270   29   15   6.7   3.7   35.6  96.0     5.8      M    M
 28000  -23.4 -10.1   270   25   13   7.5   4.1   34.6  94.3     5.0      M    M
 27000  -21.2  -6.2   265   20   10   7.5   4.1   33.7  92.6     4.3      M    M
 26000  -18.9  -2.0   260   16    8   7.5   4.1   32.9  91.2     3.7      M    M
 25000  -16.7   1.9   255   12    6   6.4   3.5   32.1  89.8     3.1      M    M
 24000  -15.1   4.8   255   14    7   5.8   3.2   30.6  87.1     1.8      M    M
 23000  -13.4   7.9   255   15    8   5.9   3.2   29.2  84.6     0.6      M    M
 22000  -11.7  10.9   260   16    8   6.7   3.7   28.0  82.4    -0.6   1297  6.6
 21000   -9.6  14.7   265   14    7   7.0   3.8   27.0  80.6    -1.5   1205  6.1
 20000   -7.5  18.5   280   13    7   7.0   3.9   26.1  79.0    -2.3   1112  5.7
 19500   -6.4  20.5   285   12    6   7.0   3.8   25.7  78.2    -2.7   1066  5.4
 19000   -5.4  22.3   285   12    6   6.9   3.8   25.2  77.4    -3.1   1021  5.2
 18500   -4.4  24.1   290   12    6   6.9   3.8   24.7  76.5    -3.6    976  5.0
 18000   -3.4  25.9   290   11    6   7.1   3.9   24.3  75.7    -4.1    932  4.7
 17500   -2.4  27.7   285   11    6   7.3   4.0   23.9  75.0    -4.6    886  4.5
 17000   -1.4  29.5   285   11    6   7.5   4.1   23.5  74.2    -5.1    841  4.3
 16500   -0.2  31.6   285   11    5   9.2   5.1   23.3  73.9    -5.3    790  4.0
 16000    1.1  34.0   280   10    5   9.1   5.0   23.2  73.7    -5.5    736  3.7
 15500    2.5  36.5   280   10    5   9.1   5.0   23.1  73.5    -5.7    682  3.5
 15000    3.8  38.8   280    9    5   9.2   5.0   23.0  73.3    -5.9    628  3.2
 14500    5.8  42.4   285    9    5   9.3   5.1   22.8  73.1    -6.1    546  2.8
 14000    7.1  44.8   290    9    4   9.2   5.0   22.8  73.0    -6.3    491  2.5
 13500    8.4  47.1   295    8    4   9.8   5.4   22.7  72.9    -6.4    436  2.2
 13000    9.7  49.5   305    9    4   7.9   4.3   22.6  72.6    -6.6    383  1.9
 12500   10.9  51.6   310    9    5   8.0   4.4   22.3  72.1    -6.9    332  1.7
 12000   12.1  53.8   315   10    5   7.5   4.1   22.0  71.7    -7.2    282  1.4
 11750   12.6  54.7   320   10    5   7.0   3.8   21.8  71.3    -7.5    259  1.3
 11500   13.2  55.8   320   11    6   7.1   3.9   21.6  70.9    -7.7    236  1.2
 11250   13.7  56.7   320   11    6   7.1   3.9   21.4  70.5    -7.9    213  1.1
 11000   14.2  57.6   320   11    6   6.8   3.7   21.2  70.2    -8.1    190  1.0
 10750   14.7  58.5   320   12    6   8.0   4.4   21.0  69.8    -8.4    167  0.8
 10500   15.2  59.4   320   12    6   4.1   2.3   20.8  69.5    -8.6    143  0.7
 10250   15.3  59.5   315   12    6  -0.1  -0.1   20.1  68.3    -9.3    135  0.7
 10000   15.2  59.4   310   12    6  -1.6  -0.9   19.4  66.9   -10.1    128  0.7
  9750   15.2  59.4   310   12    6   5.4   3.0   18.6  65.6   -10.9    122  0.6
  9500   15.6  60.1   305   12    6  -4.4  -2.4   18.3  65.0   -11.3    104  0.5
  9250   13.7  56.7   295    8    4 -43.4 -23.8   15.8  60.4   -13.9    152  0.8
  9000   11.5  52.7   260    5    3  19.1  10.5   12.9  55.2   -16.9    212  1.1
  8750      M     M     M    M    M     M     M      M     M       M      M    M
  8500      M     M     M    M    M     M     M      M     M       M      M    M
  8250      M     M     M    M    M     M     M      M     M       M      M    M
  8000      M     M     M    M    M     M     M      M     M       M      M    M

 * * * * * * Numerical weather prediction model forecast data valid * * * * * *

           06/24/2024 at 0900 MDT          |       06/24/2024 at 1200 MDT
                                           |
CAPE...  +510.8    LI...       -2.4        | CAPE...  +543.6    LI...       -3.1
CINH...   -28.0    K Index... +22.2        | CINH...    -0.2    K Index... +27.7
                                           |
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 -64.0 -83.2  265  33 17   3.4   1.9 | -63.8 -82.8  265  34 17   3.6   2.0
 45000 -57.1 -70.8  265  46 24   5.8   3.2 | -56.9 -70.4  265  48 25   5.7   3.1
 40000 -48.2 -54.8  270  51 26   6.6   3.6 | -48.1 -54.6  270  54 28   6.5   3.6
 38000 -44.2 -47.6  265  51 26   6.6   3.6 | -44.2 -47.6  265  55 28   6.5   3.6
 36000 -40.2 -40.4  265  50 26   6.6   3.6 | -40.3 -40.5  265  56 29   6.7   3.7
 34000 -36.3 -33.3  265  45 23   6.5   3.6 | -36.2 -33.2  265  53 27   6.8   3.7
 32000 -32.4 -26.3  265  41 21   6.8   3.7 | -32.1 -25.8  260  50 26   7.2   3.9
 30000 -27.8 -18.0  265  35 18   6.9   3.8 | -27.6 -17.7  265  39 20   6.7   3.6
 29000 -25.7 -14.3  265  32 16   6.9   3.8 | -25.6 -14.1  265  34 18   6.7   3.7
 28000 -23.6 -10.5  265  29 15   7.3   4.0 | -23.6 -10.5  265  30 16   6.9   3.8
 27000 -21.5  -6.7  265  26 13   7.3   4.0 | -21.5  -6.7  265  27 14   6.9   3.8
 26000 -19.3  -2.7  265  23 12   7.3   4.0 | -19.5  -3.1  265  25 13   6.9   3.8
 25000 -17.2   1.0  260  20 10   6.5   3.6 | -17.4   0.7  260  22 11   6.4   3.5
 24000 -15.4   4.3  255  18  9   6.1   3.3 | -15.7   3.7  260  19 10   6.1   3.3
 23000 -13.6   7.5  250  16  8   6.1   3.4 | -13.9   7.0  260  15  8   6.2   3.4
 22000 -11.8  10.8  245  15  7   6.8   3.7 | -12.1  10.2  260  12  6   6.5   3.6
 21000  -9.8  14.4  250  13  7   7.0   3.9 | -10.2  13.6  260  10  5   6.7   3.7
 20000  -7.7  18.1  255  11  6   7.0   3.9 |  -8.2  17.2  265   9  4   6.8   3.7
 19500  -6.7  19.9  260  11  6   7.0   3.9 |  -7.3  18.9  265   8  4   7.0   3.8
 19000  -5.6  21.9  260  11  5   7.0   3.8 |  -6.2  20.8  270   8  4   7.8   4.3
 18500  -4.6  23.7  265  11  6   7.0   3.8 |  -5.1  22.8  270   8  4   7.8   4.3
 18000  -3.6  25.5  270  11  6   7.6   4.1 |  -3.9  25.0  275   8  4   8.4   4.6
 17500  -2.5  27.5  270  10  5   7.8   4.3 |  -2.7  27.1  275   7  4   8.6   4.7
 17000  -1.3  29.7  275   9  5   7.9   4.4 |  -1.4  29.5  280   7  3   8.8   4.8
 16500  -0.1  31.8  280   8  4   9.0   5.0 |  -0.1  31.8  285   6  3   9.3   5.1
 16000   1.2  34.2  285   7  3   9.0   4.9 |   1.2  34.2  290   6  3   9.3   5.1
 15500   2.5  36.5  295   6  3   8.7   4.8 |   2.5  36.5  295   6  3   9.6   5.3
 15000   3.8  38.8  300   5  3   8.7   4.8 |   4.7  40.5  295   6  3   9.6   5.3
 14500   5.6  42.1  320   5  3   7.9   4.3 |   6.0  42.8  295   6  3   9.5   5.2
 14000   6.8  44.2  330   6  3   8.4   4.6 |   7.5  45.5  295   5  3   9.9   5.4
 13500   8.2  46.8  340   7  3   9.7   5.3 |   9.0  48.2  300   5  3   9.7   5.3
 13000   9.4  48.9  340   8  4   7.2   3.9 |  10.4  50.7  300   5  3   9.7   5.3
 12500  10.5  50.9  340   9  5   8.2   4.5 |  11.9  53.4  300   5  3   9.6   5.3
 12000  11.8  53.2  340  10  5   8.3   4.5 |  13.3  55.9  300   5  3  10.1   5.6
 11750  12.4  54.3  340  11  6   8.2   4.5 |  14.1  57.4  300   5  3  10.7   5.8
 11500  12.9  55.2  340  11  6   7.7   4.2 |  14.8  58.6  300   5  3  10.0   5.5
 11250  13.4  56.1  335  12  6   7.2   4.0 |  15.6  60.1  300   5  3   9.5   5.2
 11000  14.0  57.2  335  12  6   7.0   3.9 |  16.3  61.3  300   5  3   9.6   5.3
 10750  14.5  58.1  335  12  6   9.6   5.3 |  17.0  62.6  305   5  3  10.6   5.8
 10500  15.2  59.4  330  12  6   9.2   5.0 |  17.8  64.0  305   5  3  11.1   6.1
 10250  15.7  60.3  325  11  6   6.5   3.5 |  18.6  65.5  305   5  2  10.5   5.8
 10000  16.2  61.2  320  10  5   7.3   4.0 |  19.4  66.9  305   5  2  11.3   6.2
  9750  16.6  61.9  315   9  5   6.5   3.6 |  20.2  68.4  305   5  2   8.7   4.8
  9500  17.2  63.0  305   8  4  12.4   6.8 |  21.3  70.3  305   4  2  15.0   8.2
  9250  18.5  65.3  300   7  4  23.4  12.9 |  22.7  72.9  305   4  2  33.6  18.4
  9000  19.8  67.6  290   6  3   3.7   2.0 |  24.6  76.3  300   4  2   3.4   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

           06/24/2024 at 1500 MDT          |       06/24/2024 at 1800 MDT
                                           |
CAPE...  +523.5    LI...       -2.3        | CAPE...  +568.1    LI...       -2.6
CINH...    -1.2    K Index... +31.7        | CINH...    -3.3    K Index... +31.1
                                           |
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 -63.8 -82.8  265  34 18   3.4   1.9 | -64.2 -83.6  270  37 19   3.8   2.1
 45000 -56.8 -70.2  270  50 26   5.9   3.2 | -56.8 -70.2  275  51 26   6.1   3.3
 40000 -47.9 -54.2  275  61 31   6.2   3.4 | -47.6 -53.7  275  61 31   6.1   3.3
 38000 -44.1 -47.4  270  61 31   6.2   3.4 | -44.0 -47.2  275  60 31   6.1   3.3
 36000 -40.4 -40.7  270  61 31   6.4   3.5 | -40.3 -40.5  275  59 30   6.6   3.6
 34000 -36.4 -33.5  265  56 29   6.8   3.7 | -36.1 -33.0  275  52 27   7.1   3.9
 32000 -31.8 -25.2  265  51 26   6.7   3.7 | -31.8 -25.2  275  45 23   7.2   3.9
 30000 -28.0 -18.4  265  41 21   6.4   3.5 | -27.3 -17.1  275  39 20   6.7   3.7
 29000 -26.1 -15.0  270  36 19   6.4   3.5 | -25.3 -13.5  275  37 19   6.7   3.7
 28000 -24.1 -11.4  270  32 17   7.9   4.3 | -23.2  -9.8  275  35 18   7.2   4.0
 27000 -21.8  -7.2  270  30 15   7.8   4.3 | -21.0  -5.8  275  34 17   7.2   3.9
 26000 -19.4  -2.9  270  28 14   7.8   4.3 | -18.9  -2.0  275  32 17   7.2   4.0
 25000 -17.1   1.2  270  25 13   7.2   3.9 | -16.8   1.8  270  31 16   6.9   3.8
 24000 -15.2   4.6  265  20 10   6.8   3.8 | -14.8   5.4  275  28 14   7.0   3.8
 23000 -13.2   8.2  260  14  7   7.0   3.8 | -12.8   9.0  275  24 13   7.2   3.9
 22000 -11.2  11.8  250   9  5   7.2   3.9 | -10.8  12.6  275  21 11   7.0   3.9
 21000  -9.1  15.6  250   8  4   7.3   4.0 |  -8.8  16.2  275  17  9   7.0   3.8
 20000  -7.1  19.2  250   6  3   7.3   4.0 |  -6.8  19.8  275  12  6   7.0   3.9
 19500  -6.0  21.2  250   6  3   7.4   4.1 |  -5.8  21.6  270  10  5   7.1   3.9
 19000  -4.9  23.2  255   5  3   8.0   4.4 |  -4.8  23.4  270   9  5   7.4   4.0
 18500  -3.8  25.2  265   5  3   8.0   4.4 |  -3.7  25.3  270   9  5   7.4   4.1
 18000  -2.7  27.1  275   5  3   7.4   4.1 |  -2.7  27.1  275   9  4   7.2   3.9
 17500  -1.7  28.9  280   5  3   7.1   3.9 |  -1.7  28.9  270   8  4   7.1   3.9
 17000  -0.6  30.9  290   5  3   7.1   3.9 |  -0.6  30.9  270   8  4   7.3   4.0
 16500   1.0  33.8  295   5  3   7.9   4.3 |   0.5  32.9  270   7  4   8.9   4.9
 16000   2.2  36.0  295   5  3   8.3   4.5 |   1.8  35.2  265   6  3   8.7   4.8
 15500   3.6  38.5  295   5  3   9.9   5.4 |   3.1  37.6  260   5  3   9.4   5.2
 15000   5.0  41.0  300   5  3   9.9   5.4 |   4.5  40.1  260   5  3   9.4   5.2
 14500   6.4  43.5  300   5  3   9.1   5.0 |   5.9  42.6  260   5  3   8.3   4.5
 14000   7.8  46.0  300   5  3   9.1   5.0 |   7.2  45.0  260   5  2  10.3   5.7
 13500   9.1  48.4  300   5  3   9.2   5.0 |   8.7  47.7  260   5  2   9.2   5.0
 13000  10.5  50.9  300   6  3   9.4   5.1 |  10.0  50.0  255   5  2   9.8   5.4
 12500  11.9  53.4  300   6  3  10.1   5.6 |  12.4  54.3  255   4  2   8.9   4.9
 12000  13.4  56.1  300   6  3   9.9   5.5 |  13.6  56.5  250   4  2  10.3   5.7
 11750  14.2  57.6  300   6  3   9.5   5.2 |  14.5  58.1  250   4  2  12.5   6.9
 11500  14.9  58.8  300   6  3   9.5   5.2 |  15.3  59.5  245   4  2  10.1   5.5
 11250  15.6  60.1  300   6  3   9.3   5.1 |  16.0  60.8  245   4  2   8.2   4.5
 11000  16.3  61.3  300   6  3   9.3   5.1 |  16.6  61.9  245   4  2   8.6   4.7
 10750  17.0  62.6  300   6  3  10.3   5.7 |  17.3  63.1  240   4  2  10.7   5.9
 10500  17.8  64.0  300   6  3  10.9   6.0 |  18.2  64.8  240   4  2  11.0   6.0
 10250  18.6  65.5  300   6  3  10.5   5.8 |  18.9  66.0  235   4  2   9.3   5.1
 10000  19.4  66.9  300   6  3  10.8   5.9 |  19.6  67.3  235   4  2   9.2   5.1
  9750  20.2  68.4  300   6  3   9.8   5.4 |  20.3  68.5  235   4  2  10.4   5.7
  9500  20.9  69.6  300   6  3  11.7   6.4 |  21.2  70.2  230   4  2  11.7   6.4
  9250  22.0  71.6  300   5  3  19.0  10.4 |  21.9  71.4  225   4  2  10.1   5.5
  9000  23.3  73.9  305   5  2  12.6   6.9 |  22.6  72.7  225   4  2  12.4   6.8
  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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