Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 201312
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0712 MDT Friday, May 20, 2016

This forecast is for Friday, May 20, 2016:

If the trigger temperature of 62.0 F/16.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 870 ft/min (4.4 m/s)
   Maximum height of thermals.................. 17934 ft MSL (11176 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12512 ft MSL (5754 ft AGL)
Thermal soaring outlook for Saturday 05/21..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:42:03 / 20:08:56 MDT
Total possible sunshine........... 14 hr 26 min 54 sec (866 min 54 sec)
Altitude of sun at 12:55:41 MDT... 71.22 degrees

Upper air data from numerical model forecast valid on 05/20/2016 at 0600 MDT

Freezing level.................. 13033 ft MSL (6275 ft AGL)
Convective condensation level... 15284 ft MSL (8526 ft AGL)
Lifted condensation level....... 15738 ft MSL (8981 ft AGL)
Lifted index.................... -2.0
K index......................... +15.5

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  -60.7 -77.3   255   23   12  -0.7  -0.4      M     M       M      M    M
 45000  -61.8 -79.2   255   30   16  -1.0  -0.5      M     M       M      M    M
 40000  -63.7 -82.7   280   37   19  -1.0  -0.6      M     M       M      M    M
 38000  -60.5 -76.9   285   36   18   8.0   4.4      M     M       M      M    M
 36000  -55.7 -68.3   280   33   17   8.0   4.4      M     M       M      M    M
 34000  -50.8 -59.4   280   29   15   8.6   4.7      M     M       M      M    M
 32000  -45.6 -50.1   285   23   12   8.6   4.7      M     M       M      M    M
 30000  -40.4 -40.7   290   19   10   8.6   4.7   29.4  84.9     6.8      M    M
 29000  -37.2 -35.0   290   17    9   8.6   4.7   28.8  83.8     6.4      M    M
 28000  -34.6 -30.3   290   16    8   8.6   4.7   28.4  83.2     6.2      M    M
 27000  -32.1 -25.8   285   15    8   8.4   4.6   28.0  82.4     5.9      M    M
 26000  -29.6 -21.3   290   14    7   8.4   4.6   27.4  81.4     5.5      M    M
 25000  -27.1 -16.8   290   14    7   8.4   4.6   27.0  80.5     5.2      M    M
 24000  -24.6 -12.3   290   14    7   8.0   4.4   26.5  79.7     4.9      M    M
 23000  -22.2  -8.0   290   14    7   8.0   4.4   25.8  78.4     4.4      M    M
 22000  -19.8  -3.6   290   13    7   8.0   4.4   25.2  77.4     3.9      M    M
 21000  -17.6   0.3   285   13    7   6.1   3.4   24.4  75.9     3.3      M    M
 20000  -15.7   3.7   280   11    6   6.3   3.4   23.1  73.6     2.2      M    M
 19500  -14.8   5.4   275   11    6   6.3   3.4   22.5  72.6     1.6      M    M
 19000  -13.9   7.0   275   10    5   6.3   3.4   22.0  71.6     1.1      M    M
 18500  -13.0   8.6   270   10    5   6.7   3.7   21.5  70.6     0.6      M    M
 18000  -12.0  10.4   260   10    5   6.8   3.7   20.9  69.7     0.1      M    M
 17500  -11.0  12.2   255    9    5   7.3   4.0   20.4  68.8    -0.4   1039  5.3
 17000   -9.9  14.2   255    9    4   7.8   4.3   20.1  68.2    -0.7    990  5.0
 16500   -8.8  16.2   260    8    4   7.8   4.3   19.8  67.6    -1.0    940  4.8
 16000   -7.6  18.3   260    7    4   7.7   4.2   19.4  67.0    -1.3    892  4.5
 15500   -6.5  20.3   265    7    3   7.7   4.2   19.1  66.4    -1.7    843  4.3
 15000   -5.3  22.5   270    6    3   8.0   4.4   18.8  65.8    -2.0    794  4.0
 14500   -3.6  25.5   275    5    3   8.0   4.4   18.4  65.1    -2.5    719  3.7
 14000   -2.3  27.9   285    5    2   9.0   5.0   18.2  64.8    -2.7    667  3.4
 13500   -1.0  30.2   300    5    2   8.9   4.9   18.1  64.5    -2.8    612  3.1
 13000    0.4  32.7   310    5    3   9.2   5.0   18.0  64.3    -2.9    557  2.8
 12500    1.7  35.1   310    7    3   9.0   4.9   17.9  64.2    -3.0    500  2.5
 12000    3.0  37.4   315    9    5   8.5   4.6   17.7  63.8    -3.2    447  2.3
 11750    3.6  38.5   315   10    5   8.5   4.7   17.6  63.7    -3.3    421  2.1
 11500    4.3  39.7   315   10    5   8.3   4.6   17.5  63.5    -3.5    395  2.0
 11250    4.9  40.8   315   11    6   9.1   5.0   17.4  63.3    -3.6    369  1.9
 11000    5.6  42.1   315   12    6   9.0   5.0   17.4  63.3    -3.6    341  1.7
 10750    6.2  43.2   310   13    7   8.1   4.5   17.3  63.1    -3.8    316  1.6
 10500    6.8  44.2   310   14    7   8.6   4.7   17.1  62.9    -3.9    291  1.5
 10250    7.4  45.3   310   15    8   7.8   4.3   17.0  62.7    -4.1    265  1.3
 10000    7.9  46.2   310   16    8   7.7   4.2   16.9  62.4    -4.2    241  1.2
  9750    8.5  47.3   310   16    8   8.5   4.7   16.8  62.2    -4.4    216  1.1
  9500    9.1  48.4   305   16    8   8.5   4.6   16.7  62.0    -4.5    190  1.0
  9250    9.7  49.5   305   17    9   8.4   4.6   16.6  61.8    -4.6    165  0.8
  9000   10.3  50.5   305   17    9   8.4   4.6   16.5  61.6    -4.8    139  0.7
  8750   10.9  51.6   300   18    9   7.9   4.3   16.3  61.4    -4.9    114  0.6
  8500   11.5  52.7   300   18   10   8.9   4.9   16.2  61.2    -5.1     89  0.5
  8250   12.1  53.8   300   19   10   4.8   2.6   16.1  61.0    -5.3     65  0.3
  8000   12.1  53.8   295   19   10  -2.2  -1.2   15.4  59.7    -6.0     57  0.3
  7750   11.9  53.4   295   18   10   0.8   0.5   14.5  58.2    -6.9     54  0.3
  7500   12.3  54.1   290   17    9   8.6   4.7   14.2  57.5    -7.3     37  0.2
  7250   12.3  54.1   285   15    8 -17.3  -9.5   13.6  56.5    -7.9     28  0.1
  7000    9.0  48.2   285   11    6 -66.0 -36.2   10.2  50.3   -11.4    119  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           05/20/2016 at 0900 MDT          |       05/20/2016 at 1200 MDT
                                           |
K index... +13.7  LI... +272.1             | K index... +27.0  LI... +271.1
CAPE... +200.5  CIN... -29.0               | CAPE... +382.6  CIN... -1.3
                                           |
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 -61.6 -78.9  270  23 12  -0.9  -0.5 | -60.8 -77.4  275  25 13  -0.1  -0.1
 45000 -63.0 -81.4  270  39 20  -0.2  -0.1 | -61.1 -78.0  280  42 21  -2.1  -1.1
 40000 -63.4 -82.1  275  38 20  -0.0  -0.0 | -64.0 -83.2  270  41 21  -1.6  -0.9
 38000 -60.1 -76.2  275  35 18   7.5   4.1 | -60.6 -77.1  270  38 19   8.5   4.7
 36000 -55.7 -68.3  270  31 16   7.5   4.1 | -55.5 -67.9  265  34 17   8.5   4.7
 34000 -50.9 -59.6  265  27 14   8.6   4.7 | -50.3 -58.5  260  30 16   9.0   5.0
 32000 -45.8 -50.4  265  22 11   8.6   4.7 | -44.2 -47.6  260  27 14   9.0   5.0
 30000 -39.9 -39.8  260  18  9   8.8   4.8 | -38.9 -38.0  260  24 12   8.8   4.8
 29000 -37.3 -35.1  260  18  9   8.8   4.8 | -36.2 -33.2  260  23 12   8.8   4.8
 28000 -34.7 -30.5  255  17  9   8.8   4.8 | -33.6 -28.5  260  21 11   8.8   4.8
 27000 -32.1 -25.8  255  17  9   8.6   4.7 | -31.1 -24.0  260  20 10   7.8   4.3
 26000 -29.5 -21.1  255  16  8   8.6   4.7 | -28.8 -19.8  265  19 10   7.8   4.3
 25000 -26.9 -16.4  255  16  8   8.6   4.7 | -26.5 -15.7  265  18  9   7.8   4.3
 24000 -24.4 -11.9  260  15  8   8.2   4.5 | -24.2 -11.6  265  17  9   7.4   4.1
 23000 -22.0  -7.6  260  15  8   8.2   4.5 | -22.0  -7.6  260  16  8   7.5   4.1
 22000 -19.5  -3.1  265  14  7   8.2   4.5 | -19.8  -3.6  260  16  8   7.5   4.1
 21000 -17.3   0.9  270  13  7   6.5   3.6 | -17.6   0.3  255  15  8   7.0   3.8
 20000 -15.3   4.5  275  12  6   6.6   3.6 | -15.5   4.1  255  13  7   7.0   3.9
 19500 -14.4   6.1  275  12  6   6.6   3.6 | -14.5   5.9  255  12  6   7.0   3.9
 19000 -13.4   7.9  275  11  6   6.6   3.6 | -13.5   7.7  255  11  6   7.1   3.9
 18500 -12.4   9.7  275  11  6   6.8   3.7 | -12.4   9.7  250  11  6   6.7   3.7
 18000 -11.4  11.5  270  11  6   6.7   3.7 | -11.5  11.3  250  10  5   6.7   3.7
 17500 -10.3  13.5  265  11  6   6.4   3.5 | -10.5  13.1  250  10  5   6.9   3.8
 17000  -9.4  15.1  255  11  6   6.2   3.4 |  -9.4  15.1  245  10  5   7.0   3.8
 16500  -8.5  16.7  250  11  6   6.3   3.4 |  -8.4  16.9  240  10  5   7.0   3.8
 16000  -7.5  18.5  245  10  5   7.4   4.1 |  -6.9  19.6  240  10  5   6.8   3.7
 15500  -6.5  20.3  235   9  5   7.4   4.0 |  -5.9  21.4  235  10  5   7.0   3.8
 15000  -5.4  22.3  230   9  4   8.1   4.4 |  -4.9  23.2  235   9  5   7.5   4.1
 14500  -3.6  25.5  215   7  4   8.2   4.5 |  -3.8  25.2  235   8  4   7.6   4.1
 14000  -2.4  27.7  210   6  3   8.9   4.9 |  -2.6  27.3  230   7  4   8.4   4.6
 13500  -1.1  30.0  210   5  3   8.8   4.8 |  -1.4  29.5  225   6  3   8.2   4.5
 13000   0.2  32.4  210   4  2   9.4   5.1 |  -0.2  31.6  220   6  3   9.4   5.1
 12500   1.6  34.9  225   4  2   9.6   5.3 |   1.2  34.2  220   6  3   9.7   5.3
 12000   3.0  37.4  255   3  2   9.1   5.0 |   2.6  36.7  210   6  3   9.5   5.2
 11750   3.6  38.5  265   3  2   9.0   4.9 |   3.3  37.9  210   6  3   9.6   5.2
 11500   4.3  39.7  275   4  2   8.9   4.9 |   4.1  39.4  210   6  3   9.0   5.0
 11250   5.0  41.0  285   4  2   9.3   5.1 |   4.8  40.6  205   6  3  11.0   6.0
 11000   5.6  42.1  295   5  3   9.0   5.0 |   5.6  42.1  205   6  3  11.2   6.2
 10750   6.3  43.3  295   6  3   8.5   4.6 |   6.4  43.5  205   6  3   9.3   5.1
 10500   6.9  44.4  300   7  4   8.9   4.9 |   7.1  44.8  205   6  3  10.1   5.6
 10250   7.5  45.5  300   8  4   7.9   4.3 |   7.8  46.0  200   6  3   8.8   4.8
 10000   8.1  46.6  295   8  4   7.3   4.0 |   8.5  47.3  200   6  3   9.2   5.1
  9750   8.6  47.5  290   9  5   7.9   4.3 |   9.2  48.6  200   6  3  10.7   5.9
  9500   9.2  48.6  290  10  5   7.8   4.3 |  10.0  50.0  200   6  3  10.5   5.7
  9250   9.7  49.5  285  11  6   7.7   4.2 |  10.8  51.4  195   6  3  10.2   5.6
  9000  10.2  50.4  285  11  6   7.6   4.1 |  11.5  52.7  195   7  3   9.8   5.4
  8750  10.8  51.4  285  11  6   8.1   4.5 |  12.3  54.1  195   7  3  10.1   5.5
  8500  11.4  52.5  285  11  6   8.5   4.7 |  13.0  55.4  195   7  3  10.1   5.5
  8250  12.0  53.6  280  11  6   8.4   4.6 |  13.8  56.8  190   7  3  10.4   5.7
  8000  12.6  54.7  280  10  5   8.6   4.7 |  14.6  58.3  190   7  3  11.2   6.2
  7750  13.2  55.8  280   9  4   8.3   4.6 |  15.4  59.7  190   7  3   9.8   5.4
  7500  13.8  56.8  275   7  4   8.0   4.4 |  16.1  61.0  190   7  3   9.0   4.9
  7250  14.4  57.9  270   6  3   8.2   4.5 |  16.8  62.2  185   7  3  12.0   6.6
  7000  14.9  58.8  270   6  3   8.5   4.6 |  17.8  64.0  185   7  3  14.9   8.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/20/2016 at 1500 MDT          |       05/20/2016 at 1800 MDT
                                           |
K index... +26.7  LI... +270.8             | K index... +22.5  LI... +270.9
CAPE... +641.5  CIN... -7.2                | CAPE... +658.2  CIN... -28.6
                                           |
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 -61.0 -77.8  265  25 13   0.2   0.1 | -62.0 -79.6  270  21 11  -0.3  -0.1
 45000 -60.9 -77.6  265  36 18  -1.7  -0.9 | -62.4 -80.3  270  27 14   0.8   0.4
 40000 -63.2 -81.8  270  30 15  -1.2  -0.7 | -61.3 -78.3  295  27 14   0.1   0.1
 38000 -59.9 -75.8  270  28 14   7.9   4.3 | -57.9 -72.2  300  26 13   6.6   3.6
 36000 -55.2 -67.4  270  26 14   7.9   4.3 | -53.9 -65.0  305  24 12   6.7   3.7
 34000 -49.5 -57.1  270  25 13   9.0   5.0 | -49.2 -56.6  305  22 11   9.0   4.9
 32000 -44.0 -47.2  270  25 13   9.0   5.0 | -43.8 -46.8  295  21 11   9.0   4.9
 30000 -38.7 -37.7  275  25 13   8.7   4.8 | -38.6 -37.5  285  23 12   8.6   4.7
 29000 -36.1 -33.0  275  25 13   8.7   4.8 | -36.0 -32.8  280  26 13   8.6   4.7
 28000 -33.5 -28.3  275  26 13   8.7   4.8 | -32.8 -27.0  280  30 16   8.6   4.7
 27000 -31.0 -23.8  275  26 13   8.2   4.5 | -30.3 -22.5  275  32 17   8.1   4.4
 26000 -28.6 -19.5  270  26 13   8.2   4.5 | -27.9 -18.2  270  34 17   8.1   4.4
 25000 -26.1 -15.0  270  26 13   8.2   4.5 | -25.5 -13.9  270  35 18   8.1   4.4
 24000 -23.7 -10.7  265  26 13   7.9   4.3 | -23.1  -9.6  265  36 19   8.1   4.4
 23000 -21.3  -6.3  265  26 14   7.9   4.4 | -20.6  -5.1  265  36 19   8.1   4.4
 22000 -19.0  -2.2  265  26 14   7.9   4.3 | -18.2  -0.8  260  36 18   8.1   4.4
 21000 -16.8   1.8  260  26 13   6.9   3.8 | -16.0   3.2  260  35 18   7.0   3.8
 20000 -14.7   5.5  260  25 13   7.0   3.8 | -14.0   6.8  260  33 17   7.0   3.8
 19500 -13.7   7.3  255  24 12   7.0   3.8 | -12.9   8.8  260  32 17   7.1   3.9
 19000 -12.7   9.1  255  24 12   7.0   3.8 | -11.9  10.6  260  31 16   7.2   3.9
 18500 -11.7  10.9  250  23 12   6.8   3.7 | -10.9  12.4  255  30 15   7.3   4.0
 18000 -10.7  12.7  245  22 11   6.8   3.8 |  -9.8  14.4  250  28 15   7.3   4.0
 17500  -9.7  14.5  240  21 11   7.2   3.9 |  -8.7  16.3  245  27 14   7.7   4.2
 17000  -8.6  16.5  240  20 10   7.4   4.1 |  -7.6  18.3  245  27 14   7.9   4.3
 16500  -7.5  18.5  240  18  9   7.4   4.1 |  -6.5  20.3  240  27 14   8.1   4.5
 16000  -5.9  21.4  240  17  9   7.6   4.2 |  -5.2  22.6  235  27 14   8.9   4.9
 15500  -4.8  23.4  240  16  8   7.6   4.2 |  -4.0  24.8  235  28 14   8.9   4.9
 15000  -3.7  25.3  235  15  8   7.7   4.2 |  -2.7  27.1  230  28 14   8.9   4.9
 14500  -2.5  27.5  235  14  7   7.8   4.3 |  -1.4  29.5  225  27 14   9.0   4.9
 14000  -1.3  29.7  230  13  7   8.8   4.8 |   0.3  32.5  220  26 13   7.7   4.2
 13500  -0.1  31.8  230  12  6   8.7   4.8 |   1.4  34.5  215  25 13   7.9   4.3
 13000   1.2  34.2  225  12  6   9.2   5.0 |   2.6  36.7  210  24 13   7.7   4.2
 12500   2.6  36.7  220  12  6   9.7   5.3 |   3.7  38.7  205  24 12   8.0   4.4
 12000   4.0  39.2  210  11  6   8.4   4.6 |   4.8  40.6  200  24 12   7.4   4.1
 11750   4.6  40.3  210  12  6   8.4   4.6 |   5.4  41.7  200  24 12   7.5   4.1
 11500   5.2  41.4  205  12  6   7.8   4.3 |   5.9  42.6  195  23 12   7.3   4.0
 11250   5.8  42.4  200  12  6  10.4   5.7 |   6.4  43.5  195  23 12   8.1   4.4
 11000   6.6  43.9  195  12  6  10.8   5.9 |   7.1  44.8  190  22 11   9.0   4.9
 10750   7.3  45.1  190  12  6   8.4   4.6 |   7.7  45.9  190  22 11   8.8   4.8
 10500   8.0  46.4  185  13  7   9.4   5.1 |   8.4  47.1  190  21 11   9.3   5.1
 10250   8.6  47.5  185  13  7   8.0   4.4 |   9.1  48.4  185  21 11   7.3   4.0
 10000   9.2  48.6  180  13  7   9.0   4.9 |   9.5  49.1  185  20 10   8.1   4.5
  9750  10.0  50.0  180  13  7  10.8   5.9 |  10.3  50.5  185  20 10  10.7   5.9
  9500  10.7  51.3  180  14  7  10.3   5.7 |  11.0  51.8  180  20 10  10.2   5.6
  9250  11.5  52.7  180  14  7  10.2   5.6 |  11.8  53.2  180  19 10   9.6   5.3
  9000  12.2  54.0  180  14  7   9.8   5.4 |  12.4  54.3  180  19 10   8.8   4.8
  8750  13.0  55.4  175  14  7  10.1   5.5 |  13.1  55.6  180  19 10   9.8   5.4
  8500  13.7  56.7  175  14  7  10.2   5.6 |  13.9  57.0  180  19 10  10.4   5.7
  8250  14.5  58.1  175  14  7  10.3   5.7 |  14.6  58.3  180  19 10  10.1   5.5
  8000  15.3  59.5  175  13  7  11.1   6.1 |  15.4  59.7  180  18  9  10.2   5.6
  7750  16.1  61.0  175  13  7   9.6   5.3 |  16.2  61.2  180  18  9   9.5   5.2
  7500  16.7  62.1  175  13  7   8.5   4.6 |  16.8  62.2  180  17  9   8.5   4.6
  7250  17.4  63.3  175  13  7  11.7   6.4 |  17.4  63.3  175  16  8   8.0   4.4
  7000  18.4  65.1  170  12  6  15.3   8.4 |  17.9  64.2  175  14  7   6.9   3.8
  6750     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) and again by approximately 1830 MST/1930 MDT (0130 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 the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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.

042613



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