Soaring Guidance
Issued by NWS Pueblo, CO

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005
UXUS97 KPUB 190948
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0348 MDT Tuesday, July 19, 2016

This forecast is for Tuesday, July 19, 2016:

If the trigger temperature of 78.1 F/25.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1067 ft/min (5.4 m/s)
   Maximum height of thermals.................. 18092 ft MSL (10922 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
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................. 12896 ft MSL (5726 ft AGL)
Thermal soaring outlook for Wednesday 07/20.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:49:25 / 20:21:26 MDT
Total possible sunshine........... 14 hr 32 min 1 sec (872 min 1 sec)
Altitude of sun at 13:05:19 MDT... 71.68 degrees

Upper air data from numerical model forecast valid on 07/19/2016 at 0600 MDT

Freezing level.................. 16327 ft MSL (9157 ft AGL)
Convective condensation level... 14996 ft MSL (7826 ft AGL)
Lifted condensation level....... 16006 ft MSL (8836 ft AGL)
Lifted index.................... -3.1
K index......................... +28.6

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  -66.7 -88.1   215   11    6   1.2   0.6      M     M       M      M    M
 45000  -61.9 -79.4   225   17    9   6.7   3.7      M     M       M      M    M
 40000  -51.6 -60.9   210   22   11   7.4   4.1      M     M       M      M    M
 38000  -46.6 -51.9   215   19   10   7.4   4.1      M     M       M      M    M
 36000  -42.1 -43.8   225   17    9   8.6   4.7      M     M       M      M    M
 34000  -37.0 -34.6   230   16    8   8.5   4.7      M     M       M      M    M
 32000  -31.9 -25.4   235   15    8   9.0   5.0   44.8 112.6    12.0      M    M
 30000  -27.0 -16.6   235   15    8   8.2   4.5   43.3 110.0    11.2      M    M
 29000  -24.6 -12.3   235   15    8   8.2   4.5   42.8 109.1    10.9      M    M
 28000  -22.3  -8.1   235   15    8   6.6   3.6   42.1 107.8    10.4      M    M
 27000  -20.3  -4.5   240   15    8   6.8   3.7   40.9 105.6     9.5      M    M
 26000  -18.4  -1.1   245   15    8   6.8   3.7   39.8 103.7     8.7      M    M
 25000  -16.4   2.5   250   15    8   6.4   3.5   38.9 102.0     7.9      M    M
 24000  -14.2   6.4   245   16    8   6.2   3.4   37.1  98.8     6.5      M    M
 23000  -12.4   9.7   240   17    9   6.2   3.4   35.9  96.6     5.4      M    M
 22000  -10.6  12.9   235   18    9   6.0   3.3   34.7  94.4     4.4      M    M
 21000   -8.9  16.0   220   20   10   6.0   3.3   33.3  91.9     3.2      M    M
 20000   -7.1  19.2   215   22   12   6.0   3.3   32.0  89.7     2.1      M    M
 19500   -6.2  20.8   210   24   12   6.0   3.3   31.5  88.6     1.6      M    M
 19000   -5.4  22.3   205   25   13   6.0   3.3   30.8  87.5     1.0      M    M
 18500   -4.5  23.9   205   26   13   6.0   3.3   30.2  86.3     0.4      M    M
 18000   -3.5  25.7   200   26   14   7.1   3.9   29.6  85.4    -0.1   1058  5.4
 17500   -2.5  27.5   205   26   14   7.0   3.8   29.2  84.5    -0.6   1013  5.1
 17000   -1.5  29.3   205   26   14   7.4   4.0   28.7  83.7    -1.0    967  4.9
 16500   -0.4  31.3   205   26   14   7.6   4.2   28.4  83.1    -1.4    919  4.7
 16000    0.7  33.3   205   26   13   7.7   4.2   28.0  82.4    -1.7    871  4.4
 15500    1.9  35.4   205   25   13   8.1   4.4   27.7  81.9    -2.0    822  4.2
 15000    3.0  37.4   210   24   12   8.0   4.4   27.5  81.4    -2.3    771  3.9
 14500    4.3  39.7   210   23   12   9.0   5.0   27.2  81.0    -2.5    719  3.7
 14000    5.6  42.1   215   21   11   9.0   4.9   27.1  80.8    -2.7    665  3.4
 13500    6.9  44.4   220   19   10   9.1   5.0   27.0  80.6    -2.8    610  3.1
 13000    8.3  46.9   225   18    9   9.1   5.0   26.9  80.4    -3.0    556  2.8
 12500    9.6  49.3   230   17    9   8.4   4.6   26.8  80.3    -3.1    502  2.5
 12000   11.0  51.8   230   17    9  10.5   5.8   26.7  80.1    -3.2    446  2.3
 11750   11.7  53.1   230   16    8  10.2   5.6   26.8  80.2    -3.2    415  2.1
 11500   12.5  54.5   230   16    8  10.2   5.6   26.8  80.3    -3.1    385  2.0
 11250   13.2  55.8   230   16    8  10.0   5.5   26.9  80.3    -3.1    356  1.8
 11000   13.9  57.0   230   16    8   9.5   5.2   26.9  80.4    -3.2    327  1.7
 10750   14.6  58.3   230   16    8   9.2   5.0   26.8  80.3    -3.2    300  1.5
 10500   15.2  59.4   230   16    8   9.3   5.1   26.8  80.2    -3.3    273  1.4
 10250   15.9  60.6   230   17    9   9.5   5.2   26.7  80.1    -3.4    246  1.3
 10000   16.5  61.7   230   17    9   9.0   4.9   26.7  80.1    -3.5    220  1.1
  9750   17.6  63.7   235   18    9   6.8   3.7   26.4  79.5    -3.9    172  0.9
  9500   18.1  64.6   230   18    9   6.7   3.7   26.2  79.1    -4.2    151  0.8
  9250   18.6  65.5   230   17    9   6.6   3.6   25.9  78.7    -4.4    129  0.7
  9000   19.0  66.2   230   16    8   7.1   3.9   25.7  78.3    -4.7    108  0.5
  8750   19.5  67.1   230   15    8   5.1   2.8   25.5  77.9    -5.0     86  0.4
  8500   19.7  67.5   225   13    7   3.1   1.7   25.0  77.0    -5.5     72  0.4
  8250   20.0  68.0   225   11    6   2.9   1.6   24.5  76.1    -6.0     58  0.3
  8000   20.2  68.4   220   10    5   4.5   2.5   24.0  75.3    -6.5     44  0.2
  7750   20.4  68.7   215    8    4  -1.1  -0.6   23.6  74.4    -7.0     30  0.2
  7500   19.6  67.3   215    6    3 -15.1  -8.3   22.2  71.9    -8.6     47  0.2
  7250   18.8  65.8   225    3    2  11.6   6.4   20.8  69.5   -10.1     63  0.3
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/19/2016 at 0900 MDT          |       07/19/2016 at 1200 MDT
                                           |
K index... +18.7  LI... +269.3             | K index... +24.7  LI... +271.0
CAPE... +1092.7  CIN... -30.4              | CAPE... +442.1  CIN... -2.8
                                           |
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 -65.8 -86.4  205  11  6   1.1   0.6 | -65.4 -85.7  205  13  7   2.2   1.2
 45000 -61.5 -78.7  210  13  7   6.0   3.3 | -60.5 -76.9  195  18  9   5.1   2.8
 40000 -51.5 -60.7  205  25 13   7.6   4.1 | -51.4 -60.5  200  29 15   8.2   4.5
 38000 -46.9 -52.4  210  20 10   7.6   4.2 | -46.4 -51.5  205  24 13   8.2   4.5
 36000 -42.3 -44.1  220  16  8   8.7   4.8 | -41.4 -42.5  205  20 11   8.5   4.6
 34000 -37.1 -34.8  225  16  8   8.6   4.7 | -36.4 -33.5  210  17  9   8.5   4.6
 32000 -32.0 -25.6  230  15  8   8.9   4.9 | -31.3 -24.3  215  14  7   8.3   4.6
 30000 -27.2 -17.0  225  15  8   7.9   4.4 | -26.9 -16.4  210  14  7   7.4   4.1
 29000 -24.9 -12.8  225  15  8   8.0   4.4 | -24.7 -12.5  205  14  7   7.4   4.1
 28000 -22.6  -8.7  220  15  8   7.3   4.0 | -22.6  -8.7  205  14  7   6.9   3.8
 27000 -20.4  -4.7  225  15  8   7.3   4.0 | -20.5  -4.9  205  15  8   6.9   3.8
 26000 -18.3  -0.9  225  14  7   7.3   4.0 | -17.9  -0.2  205  15  8   7.0   3.8
 25000 -15.6   3.9  225  14  7   6.5   3.6 | -15.9   3.4  205  15  8   6.6   3.6
 24000 -13.7   7.3  225  13  7   6.6   3.6 | -14.0   6.8  210  15  8   6.7   3.7
 23000 -11.8  10.8  230  12  6   6.6   3.6 | -12.0  10.4  215  14  7   6.7   3.7
 22000  -9.9  14.2  225  11  6   5.8   3.2 | -10.1  13.8  220  14  7   6.5   3.6
 21000  -8.2  17.2  220  13  7   5.9   3.2 |  -8.1  17.4  225  16  8   6.6   3.6
 20000  -6.5  20.3  210  15  8   5.9   3.3 |  -6.2  20.8  225  17  9   6.6   3.6
 19500  -5.6  21.9  210  16  8   5.3   2.9 |  -5.3  22.5  230  18  9   6.2   3.4
 19000  -4.8  23.4  210  18  9   5.0   2.8 |  -4.3  24.3  225  19 10   6.1   3.3
 18500  -4.0  24.8  205  20 10   5.0   2.7 |  -3.4  25.9  225  19 10   6.1   3.3
 18000  -3.1  26.4  205  22 11   6.6   3.6 |  -2.5  27.5  225  20 10   6.0   3.3
 17500  -2.1  28.2  205  23 12   6.5   3.6 |  -1.7  28.9  225  20 10   6.0   3.3
 17000  -1.1  30.0  205  24 12   7.3   4.0 |  -0.8  30.6  225  21 11   6.2   3.4
 16500   0.0  32.0  200  24 13   7.8   4.3 |   0.1  32.2  220  20 10   6.4   3.5
 16000   1.2  34.2  200  25 13   7.9   4.3 |   1.0  33.8  220  19 10   6.6   3.6
 15500   2.4  36.3  200  25 13   8.4   4.6 |   2.0  35.6  220  17  9   7.9   4.3
 15000   3.6  38.5  200  24 13   8.3   4.6 |   3.1  37.6  220  15  8   7.8   4.3
 14500   4.8  40.6  200  24 12   8.7   4.8 |   4.3  39.7  220  13  7   9.0   4.9
 14000   6.1  43.0  200  24 12   8.7   4.8 |   5.6  42.1  220  12  6   9.0   4.9
 13500   7.3  45.1  200  23 12   9.3   5.1 |   6.9  44.4  220  11  6   9.3   5.1
 13000   8.6  47.5  200  21 11   9.4   5.2 |   8.3  46.9  220  10  5   9.4   5.2
 12500  10.0  50.0  205  19 10   8.2   4.5 |   9.6  49.3  220   9  5   8.5   4.6
 12000  11.2  52.2  210  17  9  10.1   5.6 |  11.0  51.8  215   9  4  10.7   5.8
 11750  11.9  53.4  210  16  8   9.9   5.4 |  11.7  53.1  215   9  4  10.3   5.7
 11500  12.6  54.7  210  15  8   9.4   5.2 |  12.5  54.5  215   9  4  10.2   5.6
 11250  13.3  55.9  215  14  7   8.7   4.8 |  13.2  55.8  210   8  4   9.8   5.4
 11000  13.9  57.0  215  13  7   9.0   4.9 |  13.9  57.0  210   8  4   9.8   5.4
 10750  14.6  58.3  215  12  6   8.9   4.9 |  14.6  58.3  210   8  4   9.7   5.3
 10500  15.2  59.4  220  12  6   9.2   5.0 |  15.4  59.7  210   8  4  10.0   5.5
 10250  15.9  60.6  220  12  6   9.8   5.4 |  16.1  61.0  205   8  4  10.5   5.8
 10000  17.2  63.0  225  12  6   7.2   4.3 |  17.6  63.7  205   8  4   9.1   5.0
  9750  17.6  63.7  230  13  6   6.9   3.8 |  18.3  64.9  200   8  4   9.4   5.1
  9500  18.2  64.8  235  13  7   7.9   4.3 |  19.0  66.2  200   8  4  10.2   5.6
  9250  18.7  65.7  240  13  7   7.7   4.2 |  19.8  67.6  200   8  4  10.4   5.7
  9000  19.2  66.6  240  14  7   8.2   4.5 |  20.5  68.9  200   8  4   9.4   5.2
  8750  19.7  67.5  245  14  7   7.9   4.3 |  21.2  70.2  195   8  4   9.6   5.3
  8500  20.2  68.4  245  12  6   7.4   4.0 |  22.0  71.6  195   8  4  10.8   5.9
  8250  20.7  69.3  240  11  6   6.8   3.7 |  22.8  73.0  195   8  4  10.7   5.9
  8000  21.2  70.2  240  10  5   9.5   5.2 |  23.6  74.5  195   8  4  10.5   5.8
  7750  22.1  71.8  235   9  5  13.4   7.4 |  24.5  76.1  190   8  4  16.2   8.9
  7500  22.9  73.2  230   8  4  11.8   6.5 |  26.0  78.8  190   8  4  26.0  14.3
  7250  23.7  74.7  225   7  3  17.5   9.6 |  27.5  81.5  190   7  4   8.5   4.6
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/19/2016 at 1500 MDT          |       07/19/2016 at 1800 MDT
                                           |
K index... +30.4  LI... +270.9             | K index... +28.2  LI... +271.0
CAPE... +578.2  CIN... -5.6                | CAPE... +502.1  CIN... -14.4
                                           |
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 -65.8 -86.4  200  18  9   1.9   1.0 | -66.5 -87.7  205  15  8   0.6   0.3
 45000 -60.8 -77.4  200  25 13   5.8   3.2 | -62.0 -79.6  210  17  9   7.1   3.9
 40000 -50.9 -59.6  190  28 14   8.2   4.5 | -50.5 -58.9  210  16  8   8.0   4.4
 38000 -46.0 -50.8  190  26 13   8.2   4.5 | -45.8 -50.4  210  15  8   8.0   4.4
 36000 -41.1 -42.0  190  24 12   8.4   4.6 | -41.0 -41.8  205  15  7   8.2   4.5
 34000 -36.1 -33.0  195  19 10   8.4   4.6 | -36.1 -33.0  200  15  8   8.1   4.5
 32000 -31.1 -24.0  205  15  8   8.3   4.6 | -31.2 -24.2  200  15  8   8.6   4.7
 30000 -26.5 -15.7  205  18  9   7.6   4.2 | -26.4 -15.5  200  18  9   8.0   4.4
 29000 -23.7 -10.7  205  20 10   7.6   4.2 | -24.0 -11.2  200  19 10   8.0   4.4
 28000 -21.5  -6.7  205  20 10   7.3   4.0 | -21.2  -6.2  200  19 10   7.3   4.0
 27000 -19.3  -2.7  205  20 10   7.4   4.0 | -19.0  -2.2  205  18  9   7.3   4.0
 26000 -17.1   1.2  210  20 10   7.4   4.0 | -16.9   1.6  210  17  9   7.4   4.0
 25000 -15.0   5.0  210  20 10   6.5   3.5 | -14.8   5.4  215  17  9   6.1   3.3
 24000 -13.1   8.4  210  19 10   6.6   3.6 | -13.0   8.6  215  15  8   6.2   3.4
 23000 -11.2  11.8  210  17  9   6.7   3.7 | -11.2  11.8  220  14  7   6.2   3.4
 22000  -9.3  15.3  210  16  8   6.2   3.4 |  -9.4  15.1  225  13  7   6.5   3.6
 21000  -7.5  18.5  220  16  8   6.3   3.4 |  -7.5  18.5  235  13  7   6.6   3.6
 20000  -5.7  21.7  230  16  8   6.3   3.4 |  -5.6  21.9  240  14  7   6.6   3.6
 19500  -4.8  23.4  235  17  9   6.0   3.3 |  -4.7  23.5  245  15  7   6.4   3.5
 19000  -4.0  24.8  240  17  9   5.7   3.1 |  -3.8  25.2  245  15  7   6.2   3.4
 18500  -3.1  26.4  245  18  9   5.7   3.1 |  -2.9  26.8  245  15  7   6.1   3.4
 18000  -2.3  27.9  245  18  9   6.4   3.5 |  -1.9  28.6  250  14  7   7.1   3.9
 17500  -1.4  29.5  250  17  9   6.4   3.5 |  -0.9  30.4  245  14  7   7.1   3.9
 17000  -0.5  31.1  250  15  8   6.7   3.7 |   0.1  32.2  245  13  7   7.1   3.9
 16500   0.5  32.9  255  14  7   7.1   3.9 |   1.1  34.0  240  13  7   7.1   3.9
 16000   1.5  34.7  255  12  6   7.1   3.9 |   2.2  36.0  235  13  6   7.1   3.9
 15500   2.6  36.7  255  11  6   8.1   4.4 |   3.2  37.8  230  12  6   7.8   4.3
 15000   3.7  38.7  250   9  5   8.0   4.4 |   4.3  39.7  225  13  6   7.7   4.2
 14500   4.9  40.8  245   8  4   8.7   4.8 |   5.5  41.9  220  13  7   8.5   4.7
 14000   6.8  44.2  225   7  4   8.9   4.9 |   7.4  45.3  210  14  7   8.7   4.8
 13500   8.1  46.6  215   7  4   9.3   5.1 |   8.7  47.7  210  14  7   9.4   5.2
 13000   9.5  49.1  210   8  4   9.6   5.3 |  10.1  50.2  205  14  7   9.6   5.3
 12500  10.7  51.3  200   9  4   8.3   4.6 |  11.3  52.3  205  14  7   8.4   4.6
 12000  12.1  53.8  190  10  5   9.5   5.2 |  12.7  54.9  200  14  7   9.2   5.1
 11750  12.8  55.0  185  10  5   9.6   5.3 |  13.3  55.9  200  15  8   9.3   5.1
 11500  13.5  56.3  185  11  5   9.5   5.2 |  14.0  57.2  200  15  8   9.5   5.2
 11250  14.2  57.6  180  11  6   9.4   5.1 |  14.7  58.5  195  15  8   9.1   5.0
 11000  14.9  58.8  180  11  6   9.2   5.0 |  15.3  59.5  195  15  8   8.6   4.7
 10750  15.6  60.1  175  12  6   9.4   5.2 |  16.0  60.8  195  15  8   8.8   4.8
 10500  16.3  61.3  175  12  6  10.4   5.7 |  16.6  61.9  190  15  8   9.1   5.0
 10250  17.1  62.8  175  12  6  10.9   6.0 |  17.3  63.1  190  16  8   9.3   5.1
 10000  17.8  64.0  175  12  6   9.5   5.2 |  17.9  64.2  190  16  8   9.1   5.0
  9750  18.5  65.3  175  13  6   9.0   4.9 |  18.6  65.5  185  16  8   8.9   4.9
  9500  19.2  66.6  175  13  7  10.1   5.5 |  19.2  66.6  185  16  8   9.3   5.1
  9250  20.0  68.0  175  13  7  10.7   5.9 |  20.0  68.0  185  16  8   9.4   5.1
  9000  20.8  69.4  170  13  7  10.1   5.6 |  20.7  69.3  185  16  8   9.7   5.3
  8750  21.5  70.7  170  13  7   9.5   5.2 |  21.4  70.5  185  16  8  10.6   5.8
  8500  22.2  72.0  170  13  7  10.1   5.6 |  22.2  72.0  185  16  8  10.4   5.7
  8250  23.0  73.4  170  13  7  10.7   5.9 |  22.9  73.2  185  16  8  10.0   5.5
  8000  23.8  74.8  170  13  7  10.4   5.7 |  23.7  74.7  185  15  8  10.1   5.5
  7750  24.5  76.1  170  13  7  11.1   6.1 |  24.4  75.9  185  15  8  10.2   5.6
  7500  25.4  77.7  170  13  7  12.0   6.6 |  25.1  77.2  185  15  8   8.7   4.8
  7250  26.2  79.2  170  12  6  11.9   6.5 |  25.6  78.1  180  14  7   7.2   3.9
  7000  27.1  80.8  170  12  6  12.1   6.6 |  26.2  79.2  180  13  7   8.3   4.6
  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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