Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 201019
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0419 MDT Saturday, August 20, 2016

This forecast is for Saturday, August 20, 2016:

If the trigger temperature of 61.2 F/16.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 183 ft/min (0.9 m/s)
   Maximum height of thermals.................. 12044 ft MSL (5286 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1130 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................. 10795 ft MSL (4038 ft AGL)
Thermal soaring outlook for Sunday 08/21....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:17:32 / 19:47:27 MDT
Total possible sunshine........... 13 hr 29 min 55 sec (809 min 55 sec)
Altitude of sun at 13:02:07 MDT... 63.15 degrees

Upper air data from numerical model forecast valid on 08/20/2016 at 0600 MDT

Freezing level.................. 14456 ft MSL (7698 ft AGL)
Convective condensation level... 14188 ft MSL (7430 ft AGL)
Lifted condensation level....... 12916 ft MSL (6158 ft AGL)
Lifted index.................... -0.2
K index......................... +23.1

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  -60.3 -76.5   270   40   20   0.6   0.3      M     M       M      M    M
 45000  -59.2 -74.6   270   50   26   1.4   0.8      M     M       M      M    M
 40000  -57.0 -70.6   265   46   24   5.0   2.8      M     M       M      M    M
 38000  -53.2 -63.8   270   41   21   6.3   3.4      M     M       M      M    M
 36000  -49.5 -57.1   275   36   18   6.3   3.4      M     M       M      M    M
 34000  -44.8 -48.6   275   34   17   8.5   4.7      M     M       M      M    M
 32000  -39.0 -38.2   275   33   17   8.5   4.7      M     M       M      M    M
 30000  -34.1 -29.4   275   31   16   8.3   4.5   35.8  96.4    12.6      M    M
 29000  -31.6 -24.9   280   29   15   8.3   4.5   35.2  95.4    12.3      M    M
 28000  -29.1 -20.4   280   28   14   8.3   4.5   34.8  94.7    12.1      M    M
 27000  -26.6 -15.9   285   26   14   8.2   4.5   34.1  93.5    11.8      M    M
 26000  -24.1 -11.4   290   25   13   8.3   4.5   33.6  92.4    11.5      M    M
 25000  -21.6  -6.9   295   24   12   8.3   4.6   33.1  91.6    11.2      M    M
 24000  -19.2  -2.6   305   24   12   7.9   4.3   32.4  90.4    10.8      M    M
 23000  -16.9   1.6   310   26   13   7.9   4.3   31.7  89.1    10.3      M    M
 22000  -14.5   5.9   320   28   14   8.1   4.5   31.1  88.0     9.9      M    M
 21000  -12.7   9.1   320   29   15   5.3   2.9   29.8  85.6     8.9      M    M
 20000  -11.1  12.0   325   30   16   5.3   2.9   28.2  82.8     7.6      M    M
 19500  -10.4  13.3   325   31   16   5.2   2.9   27.5  81.4     7.0      M    M
 19000   -9.6  14.7   325   31   16   4.3   2.3   26.7  80.1     6.4      M    M
 18500   -9.1  15.6   320   32   16   3.6   2.0   25.7  78.2     5.4      M    M
 18000   -8.6  16.5   320   32   17   3.4   1.9   24.6  76.4     4.5      M    M
 17500   -7.8  18.0   315   32   16   8.5   4.7   24.0  75.2     3.9      M    M
 17000   -6.6  20.1   315   31   16   8.3   4.5   23.7  74.7     3.6      M    M
 16500   -5.5  22.1   315   30   15   8.8   4.8   23.5  74.3     3.2      M    M
 16000   -4.3  24.3   315   27   14   9.1   5.0   23.4  74.1     3.0      M    M
 15500   -2.4  27.7   315   24   12   9.0   4.9   23.2  73.8     2.7      M    M
 15000   -1.1  30.0   315   22   12   9.0   4.9   23.1  73.6     2.5      M    M
 14500    0.2  32.4   315   21   11   8.6   4.7   23.0  73.4     2.4      M    M
 14000    1.4  34.5   315   19   10   8.2   4.5   22.7  72.9     2.1      M    M
 13500    2.6  36.7   310   19   10   7.7   4.3   22.5  72.5     1.9      M    M
 13000    3.6  38.5   300   18    9   6.5   3.6   22.0  71.7     1.4      M    M
 12500    4.5  40.1   290   18    9   3.9   2.2   21.6  70.8     0.9      M    M
 12000    4.8  40.6   280   19   10   3.1   1.7   20.3  68.6    -0.3    377  1.9
 11750    5.0  41.0   275   19   10   2.7   1.5   19.8  67.6    -0.8    364  1.9
 11500    5.1  41.2   270   20   10   2.8   1.5   19.2  66.6    -1.4    352  1.8
 11250    5.3  41.5   265   20   10   2.2   1.2   18.7  65.6    -1.9    339  1.7
 11000    5.4  41.7   265   20   10   0.7   0.4   18.0  64.5    -2.5    328  1.7
 10750    5.4  41.7   265   19   10   0.0   0.0   17.3  63.1    -3.3    321  1.6
 10500    5.4  41.7   265   19   10   0.1   0.0   16.5  61.8    -4.0    314  1.6
 10250    5.4  41.7   260   19   10  -1.0  -0.6   15.8  60.4    -4.8    307  1.6
 10000    5.3  41.5   265   18    9  -1.3  -0.7   14.9  58.8    -5.6    302  1.5
  9750    5.2  41.4   260   16    8  -0.6  -0.3   14.1  57.3    -6.4    297  1.5
  9500    5.2  41.4   260   15    8  -0.6  -0.3   13.3  55.9    -7.2    290  1.5
  9250    5.2  41.4   260   13    7  -0.7  -0.4   12.5  54.5    -8.0    284  1.4
  9000    5.1  41.2   260   11    6  -0.8  -0.4   11.7  53.0    -8.8    278  1.4
  8750    5.1  41.2   255    9    5  -0.1  -0.1   10.9  51.6    -9.6    271  1.4
  8500    5.2  41.4   250    7    3   2.7   1.5   10.2  50.4   -10.2    261  1.3
  8250    5.5  41.9   240    6    3   4.9   2.7    9.8  49.6   -10.7    245  1.2
  8000    5.8  42.4   235    5    3   4.3   2.4    9.4  49.0   -11.1    228  1.2
  7750    6.2  43.2   225    4    2   6.3   3.4    9.0  48.3   -11.5    210  1.1
  7500    6.6  43.9   200    3    2   4.7   2.6    8.9  48.0   -11.7    189  1.0
  7250    6.8  44.2   190    3    2   0.9   0.5    8.7  47.7   -11.9    177  0.9
  7000    6.9  44.4   185    3    2   3.9   2.2    8.5  47.3   -12.2    165  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/20/2016 at 0900 MDT          |       08/20/2016 at 1200 MDT
                                           |
K index... +19.0  LI... +274.1             | K index... +1.3  LI... +273.6
CAPE... +24.2  CIN... -55.7                | CAPE... +341.3  CIN... -124.8
                                           |
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 -60.9 -77.6  270  37 19   0.7   0.4 | -61.1 -78.0  265  37 19  -0.1  -0.1
 45000 -59.4 -74.9  270  45 23   2.1   1.1 | -60.3 -76.5  270  43 22   2.7   1.5
 40000 -56.2 -69.2  280  35 18   4.9   2.7 | -56.1 -69.0  285  26 14   5.2   2.8
 38000 -52.8 -63.0  280  34 17   5.7   3.1 | -52.8 -63.0  285  28 14   5.6   3.1
 36000 -49.4 -56.9  280  32 17   5.7   3.1 | -49.5 -57.1  285  29 15   5.6   3.1
 34000 -45.0 -49.0  280  30 15   8.1   4.4 | -45.2 -49.4  285  26 13   7.8   4.3
 32000 -39.5 -39.1  285  27 14   8.1   4.4 | -39.9 -39.8  295  22 11   7.8   4.3
 30000 -34.4 -29.9  295  25 13   8.6   4.7 | -34.7 -30.5  310  20 10   8.9   4.9
 29000 -31.8 -25.2  295  24 13   8.6   4.7 | -32.1 -25.8  315  20 10   8.9   4.9
 28000 -29.2 -20.6  300  24 12   8.6   4.7 | -29.4 -20.9  320  20 10   8.7   4.8
 27000 -26.7 -16.1  300  24 12   8.4   4.6 | -26.8 -16.2  320  21 11   8.5   4.7
 26000 -24.2 -11.6  300  24 12   8.4   4.6 | -24.3 -11.7  325  21 11   8.5   4.7
 25000 -21.7  -7.1  305  24 12   8.4   4.6 | -21.7  -7.1  325  22 11   8.6   4.7
 24000 -19.2  -2.6  310  24 12   8.3   4.6 | -19.3  -2.7  325  23 12   8.1   4.4
 23000 -16.7   1.9  315  25 13   8.3   4.6 | -16.9   1.6  325  24 12   8.1   4.4
 22000 -14.2   6.4  315  25 13   8.6   4.7 | -14.5   5.9  325  24 13   8.1   4.5
 21000 -12.1  10.2  320  26 13   6.4   3.5 | -12.1  10.2  325  24 13   7.8   4.3
 20000 -10.2  13.6  320  26 13   6.4   3.5 |  -9.7  14.5  325  24 12   7.8   4.3
 19500  -9.2  15.4  320  26 13   6.4   3.5 |  -8.6  16.5  325  24 12   7.8   4.3
 19000  -8.3  17.1  320  26 13   5.0   2.7 |  -7.4  18.7  325  24 12   6.6   3.6
 18500  -7.7  18.1  320  26 13   4.2   2.3 |  -6.5  20.3  325  24 13   6.2   3.4
 18000  -7.1  19.2  320  26 13   4.2   2.3 |  -5.6  21.9  320  25 13   6.1   3.4
 17500  -6.5  20.3  315  27 14   4.2   2.3 |  -4.8  23.4  320  25 13   4.6   2.5
 17000  -5.9  21.4  310  28 14   4.6   2.5 |  -4.1  24.6  315  24 12   4.8   2.6
 16500  -5.3  22.5  305  29 15   7.0   3.9 |  -3.4  25.9  315  24 12   5.1   2.8
 16000  -3.7  25.3  305  28 14   8.1   4.5 |  -2.7  27.1  310  25 13   5.5   3.0
 15500  -2.6  27.3  305  26 14   8.0   4.4 |  -1.5  29.3  305  27 14   7.8   4.3
 15000  -1.5  29.3  305  25 13   8.0   4.4 |  -0.5  31.1  300  26 13   8.1   4.4
 14500  -0.3  31.5  310  23 12   8.3   4.5 |   0.6  33.1  300  25 13   7.8   4.3
 14000   0.9  33.6  315  22 11   8.4   4.6 |   1.6  34.9  300  24 12   7.5   4.1
 13500   2.2  36.0  315  21 11   8.3   4.5 |   2.7  36.9  305  22 11   7.8   4.3
 13000   3.4  38.1  320  19 10   8.0   4.4 |   4.0  39.2  305  20 11   8.4   4.6
 12500   4.5  40.1  320  18  9   7.0   3.8 |   5.2  41.4  310  19 10   8.3   4.5
 12000   5.5  41.9  315  16  8   7.7   4.2 |   6.3  43.3  315  17  9   6.7   3.7
 11750   6.1  43.0  315  16  8   7.6   4.2 |   6.8  44.2  315  16  8   6.9   3.8
 11500   6.6  43.9  315  15  8   7.1   3.9 |   7.3  45.1  320  15  8   6.8   3.7
 11250   7.0  44.6  310  14  7   4.8   2.6 |   7.8  46.0  320  14  7   6.3   3.4
 11000   7.3  45.1  305  15  8   3.1   1.7 |   8.2  46.8  320  13  7   5.5   3.0
 10750   7.5  45.5  295  15  8   3.2   1.8 |   8.5  47.3  320  12  6   5.6   3.0
 10500   7.7  45.9  290  16  8   2.7   1.5 |   8.9  48.0  320  11  6   5.1   2.8
 10250   7.8  46.0  285  16  8   0.9   0.5 |   9.1  48.4  320  10  5   2.4   1.3
 10000   7.8  46.0  280  16  8   0.1   0.1 |   9.2  48.6  310   9  5   3.0   1.7
  9750   7.8  46.0  275  17  9   0.6   0.3 |   9.5  49.1  300   7  4   5.8   3.2
  9500   7.8  46.0  270  17  9  -0.1  -0.0 |   9.8  49.6  280   5  3   4.1   2.3
  9250   7.7  45.9  265  17  9  -1.3  -0.7 |   9.9  49.8  260   5  2   0.8   0.4
  9000   7.6  45.7  260  15  8  -1.7  -0.9 |   9.9  49.8  230   4  2   0.3   0.2
  8750   7.5  45.5  255  14  7   0.1   0.0 |  10.1  50.2  210   5  3   7.6   4.2
  8500   7.6  45.7  240  13  7   2.4   1.3 |  10.9  51.6  195   5  3  11.8   6.5
  8250   7.8  46.0  230  11  6   3.3   1.8 |  11.7  53.1  190   6  3  10.2   5.6
  8000   8.0  46.4  220  10  5   2.5   1.4 |  12.5  54.5  185   6  3  10.6   5.8
  7750   8.2  46.8  205   9  5   5.6   3.0 |  13.3  55.9  180   6  3  10.3   5.7
  7500   8.8  47.8  190   9  5   9.5   5.2 |  14.1  57.4  175   6  3  12.0   6.6
  7250   9.5  49.1  190   9  4   9.2   5.1 |  15.0  59.0  175   6  3  13.8   7.6
  7000  10.2  50.4  190   8  4   9.7   5.3 |  16.0  60.8  175   6  3  12.4   6.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/20/2016 at 1500 MDT          |       08/20/2016 at 1800 MDT
                                           |
K index... +21.7  LI... +271.5             | K index... +29.1  LI... +270.8
CAPE... +873.5  CIN... -11.3               | CAPE... +840.0  CIN... -13.1
                                           |
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 -60.5 -76.9  270  39 20   0.1   0.0 | -61.1 -78.0  275  37 19   0.6   0.3
 45000 -59.8 -75.6  270  42 22   1.8   1.0 | -59.9 -75.8  275  45 23   1.5   0.8
 40000 -56.9 -70.4  265  22 11   5.5   3.0 | -57.0 -70.6  265  37 19   7.4   4.1
 38000 -53.2 -63.8  280  23 12   6.3   3.4 | -52.9 -63.2  275  30 16   6.9   3.8
 36000 -49.4 -56.9  290  25 13   6.3   3.4 | -48.7 -55.7  290  24 13   7.0   3.8
 34000 -44.3 -47.7  300  24 12   8.0   4.4 | -43.8 -46.8  300  23 12   8.5   4.7
 32000 -39.5 -39.1  300  22 11   8.0   4.4 | -38.7 -37.7  305  22 12   8.5   4.7
 30000 -34.4 -29.9  310  20 10   8.6   4.7 | -33.8 -28.8  310  20 10   8.1   4.4
 29000 -31.8 -25.2  320  19 10   8.6   4.7 | -31.4 -24.5  315  19 10   8.1   4.4
 28000 -29.2 -20.6  325  19 10   8.6   4.7 | -29.0 -20.2  320  18  9   8.1   4.5
 27000 -26.7 -16.1  330  18 10   8.5   4.7 | -26.0 -14.8  330  17  9   7.9   4.3
 26000 -24.1 -11.4  335  18 10   8.5   4.7 | -23.7 -10.7  335  17  9   7.9   4.3
 25000 -21.5  -6.7  335  19 10   8.6   4.7 | -21.3  -6.3  340  17  9   7.9   4.3
 24000 -19.0  -2.2  335  18  9   8.4   4.6 | -18.9  -2.0  340  17  9   8.3   4.6
 23000 -16.5   2.3  335  18  9   8.4   4.6 | -16.4   2.5  340  17  9   8.3   4.6
 22000 -13.9   7.0  335  18  9   8.5   4.7 | -13.9   7.0  335  18  9   8.1   4.5
 21000 -11.7  10.9  335  19 10   7.3   4.0 | -11.9  10.6  335  21 11   6.6   3.6
 20000  -9.6  14.7  330  22 11   7.3   4.0 | -10.0  14.0  330  24 12   6.6   3.6
 19500  -8.5  16.7  330  23 12   7.4   4.0 |  -9.0  15.8  330  26 13   6.6   3.6
 19000  -7.4  18.7  325  24 12   7.1   3.9 |  -8.0  17.6  330  27 14   7.0   3.9
 18500  -6.4  20.5  325  25 13   7.0   3.8 |  -7.0  19.4  325  28 14   7.2   3.9
 18000  -5.3  22.5  325  26 13   6.9   3.8 |  -6.0  21.2  325  28 14   7.3   4.0
 17500  -4.4  24.1  325  27 14   6.1   3.3 |  -5.0  23.0  320  28 14   7.2   3.9
 17000  -3.5  25.7  320  29 15   6.4   3.5 |  -4.0  24.8  320  27 14   7.3   4.0
 16500  -2.4  27.7  315  30 15   5.0   2.7 |  -3.0  26.6  315  26 14   7.4   4.0
 16000  -1.8  28.8  305  30 15   5.3   2.9 |  -2.0  28.4  315  24 13   7.4   4.1
 15500  -1.0  30.2  300  29 15   9.0   4.9 |  -1.0  30.2  320  23 12   7.3   4.0
 15000   0.3  32.5  300  27 14   9.2   5.0 |   0.1  32.2  315  20 10   7.1   3.9
 14500   1.6  34.9  300  26 13   8.2   4.5 |   1.1  34.0  315  18  9   7.1   3.9
 14000   2.7  36.9  300  22 11   7.6   4.2 |   2.0  35.6  315  15  8   6.0   3.3
 13500   3.7  38.7  300  19 10   7.0   3.8 |   3.3  37.9  305  11  6   6.4   3.5
 13000   4.6  40.3  300  15  8   5.8   3.2 |   4.2  39.6  305   8  4   6.7   3.7
 12500   5.5  41.9  305  12  6   4.8   2.6 |   5.1  41.2  305   6  3   7.0   3.9
 12000   6.2  43.2  310   9  4   6.1   3.3 |   6.1  43.0  310   4  2   6.9   3.8
 11750   6.6  43.9  315   7  4   5.7   3.1 |   6.6  43.9  320   3  2   7.1   3.9
 11500   7.0  44.6  320   6  3   6.0   3.3 |   7.1  44.8  340   3  1   6.6   3.6
 11250   7.5  45.5  330   4  2   6.3   3.4 |   7.5  45.5  360   2  1   6.6   3.6
 11000   7.9  46.2  340   3  2   6.2   3.4 |   8.0  46.4  025   2  1   7.1   3.9
 10750   8.4  47.1  350   3  1   6.1   3.3 |   8.5  47.3  050   2  1   7.3   4.0
 10500   8.8  47.8  015   2  1   6.0   3.3 |   9.1  48.4  075   2  1   6.9   3.8
 10250   9.2  48.6  045   2  1   3.4   1.9 |   9.5  49.1  100   2  1   4.2   2.3
 10000   9.4  48.9  080   2  1   5.7   3.1 |   9.8  49.6  125   3  2   5.6   3.1
  9750  10.0  50.0  105   3  1   9.8   5.4 |  10.3  50.5  135   4  2   8.0   4.4
  9500  10.7  51.3  120   4  2   8.4   4.6 |  10.8  51.4  145   5  3   7.3   4.0
  9250  11.2  52.2  130   4  2   6.6   3.6 |  11.4  52.5  150   6  3   7.2   4.0
  9000  11.7  53.1  135   5  2   6.3   3.5 |  11.9  53.4  150   6  3   7.6   4.2
  8750  12.3  54.1  140   5  3  10.1   5.6 |  12.5  54.5  155   6  3  10.2   5.6
  8500  13.1  55.6  140   6  3  11.7   6.4 |  13.3  55.9  155   7  3  10.8   5.9
  8250  13.9  57.0  140   6  3  10.4   5.7 |  14.1  57.4  155   7  4   9.7   5.3
  8000  14.7  58.5  140   6  3  10.6   5.8 |  14.8  58.6  155   7  4   9.3   5.1
  7750  15.5  59.9  145   6  3  10.2   5.6 |  15.5  59.9  155   7  4  10.8   6.0
  7500  16.3  61.3  145   6  3  11.9   6.6 |  16.3  61.3  155   8  4  10.4   5.7
  7250  17.2  63.0  145   6  3  14.0   7.7 |  17.0  62.6  155   7  4   8.0   4.4
  7000  18.2  64.8  140   7  3  12.4   6.8 |  17.6  63.7  155   7  4   9.9   5.5
  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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