Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 231007
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0407 MDT Tuesday, June 23, 2015

This forecast is for Tuesday, June 23, 2015:

If the trigger temperature of 81.4 F/27.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 80 ft/min (0.4 m/s)
   Maximum height of thermals.................. 12417 ft MSL (5659 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10091 ft MSL (3334 ft AGL)
Thermal soaring outlook for Wednesday 06/24.... Poor

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

Remarks...

Sunrise/Sunset.................... 05:34:20 / 20:27:59 MDT
Total possible sunshine........... 14 hr 53 min 39 sec (893 min 39 sec)
Altitude of sun at 13:01:16 MDT... 74.44 degrees

Upper air data from numerical model forecast valid on 06/23/2015 at 0600 MDT

Freezing level.................. 17233 ft MSL (10475 ft AGL)
Convective condensation level... 15335 ft MSL (8577 ft AGL)
Lifted condensation level....... 14608 ft MSL (7850 ft AGL)
Lifted index.................... -7.1
K index......................... +17.4

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  -67.6 -89.7   290   32   16   0.5   0.3      M     M       M      M    M
 45000  -64.3 -83.7   280   39   20   6.3   3.5      M     M       M      M    M
 40000  -54.1 -65.4   255   32   17   7.3   4.0      M     M       M      M    M
 38000  -49.8 -57.6   260   31   16   7.3   4.0      M     M       M      M    M
 36000  -45.4 -49.7   260   31   16   7.4   4.1      M     M       M      M    M
 34000  -40.8 -41.4   265   27   14   7.7   4.2      M     M       M      M    M
 32000  -36.2 -33.2   270   24   12   7.8   4.3      M     M       M      M    M
 30000  -31.3 -24.3   270   20   10   8.1   4.5   38.4 101.0     7.4      M    M
 29000  -28.3 -18.9   270   18    9   8.1   4.5   37.7  99.8     6.9      M    M
 28000  -25.8 -14.4   270   16    8   8.7   4.8   37.2  98.9     6.6      M    M
 27000  -23.2  -9.8   270   15    8   8.7   4.8   36.7  98.1     6.3      M    M
 26000  -20.6  -5.1   265   14    7   8.7   4.8   36.4  97.4     6.1      M    M
 25000  -18.0  -0.4   265   13    7   6.6   3.6   35.9  96.7     5.9      M    M
 24000  -16.2   2.8   255   13    7   6.1   3.4   34.5  94.1     4.7      M    M
 23000  -14.4   6.1   245   14    7   6.2   3.4   33.3  91.9     3.6      M    M
 22000  -12.5   9.5   240   15    8   8.5   4.7   32.2  90.0     2.7      M    M
 21000  -10.0  14.0   235   16    8   8.7   4.8   31.8  89.3     2.3      M    M
 20000   -7.4  18.7   235   17    9   8.8   4.8   31.5  88.7     2.0      M    M
 19500   -6.1  21.0   235   18    9   8.8   4.8   31.4  88.5     1.9      M    M
 19000   -4.8  23.4   230   18    9   8.8   4.8   31.2  88.2     1.7      M    M
 18500   -3.5  25.7   230   17    9   8.8   4.8   31.1  87.9     1.6      M    M
 18000   -2.2  28.0   230   16    8   8.9   4.9   30.9  87.6     1.4      M    M
 17500   -0.9  30.4   235   15    8   8.9   4.9   30.8  87.4     1.3      M    M
 17000    0.4  32.7   235   13    7   9.1   5.0   30.6  87.1     1.2      M    M
 16500    1.8  35.2   240   12    6   9.4   5.2   30.6  87.0     1.1      M    M
 16000    3.2  37.8   245   11    6   9.5   5.2   30.5  86.9     1.1      M    M
 15500    4.6  40.3   250   10    5   9.1   5.0   30.4  86.8     1.0      M    M
 15000    6.0  42.8   255   11    5   9.1   5.0   30.3  86.6     0.9      M    M
 14500    8.0  46.4   260   11    6   9.1   5.0   30.2  86.3     0.8      M    M
 14000    9.3  48.7   260   11    6   9.2   5.0   30.1  86.1     0.6      M    M
 13500   10.7  51.3   260   12    6   9.0   4.9   30.0  85.9     0.5      M    M
 13000   11.9  53.4   260   13    6   9.3   5.1   29.8  85.7     0.3      M    M
 12500   13.1  55.6   260   14    7   7.6   4.2   29.6  85.2    -0.0    479  2.4
 12000   14.3  57.7   260   14    7   8.9   4.9   29.4  84.9    -0.2    427  2.2
 11750   14.9  58.8   255   15    8   9.1   5.0   29.3  84.8    -0.3    401  2.0
 11500   15.5  59.9   255   15    8   7.3   4.0   29.3  84.7    -0.5    376  1.9
 11250   15.9  60.6   255   16    8   6.0   3.3   29.0  84.2    -0.8    356  1.8
 11000   16.3  61.3   255   16    8   6.2   3.4   28.7  83.7    -1.1    337  1.7
 10750   16.7  62.1   255   17    9   6.9   3.8   28.4  83.2    -1.5    318  1.6
 10500   17.1  62.8   255   17    9   3.2   1.8   28.2  82.7    -1.8    299  1.5
 10250   17.0  62.6   255   18    9   0.5   0.3   27.5  81.4    -2.6    294  1.5
 10000   17.0  62.6   250   18    9  -0.3  -0.2   26.8  80.2    -3.4    289  1.5
  9750   16.7  62.1   245   18    9  -1.4  -0.7   25.9  78.6    -4.5    289  1.5
  9500   16.4  61.5   245   19   10  -4.6  -2.5   25.0  77.0    -5.5    290  1.5
  9250   15.7  60.3   235   18    9  -8.3  -4.6   23.7  74.6    -6.9    303  1.5
  9000   15.1  59.2   230   18    9  -7.2  -3.9   22.3  72.2    -8.3    316  1.6
  8750   14.4  57.9   220   18    9  -6.7  -3.7   21.1  69.9    -9.7    328  1.7
  8500   14.0  57.2   210   18    9  -0.1  -0.1   20.0  68.0   -10.9    333  1.7
  8250   14.2  57.6   205   17    9   3.6   2.0   19.5  67.1   -11.4    319  1.6
  8000   14.4  57.9   200   16    8   4.0   2.2   19.0  66.2   -12.0    305  1.5
  7750   14.7  58.5   195   15    8  -1.0  -0.6   18.5  65.3   -12.5    291  1.5
  7500   14.3  57.7   190   16    8  -2.0  -1.1   17.7  63.8   -13.4    293  1.5
  7250   14.5  58.1   185   13    7   3.9   2.1   17.4  63.4   -13.6    281  1.4
  7000   14.7  58.5   185   11    6  -1.0  -0.6   17.2  63.0   -13.8    269  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           06/23/2015 at 0900 MDT          |       06/23/2015 at 1200 MDT
                                           |
K index... +12.5  LI... +268.5             | K index... +9.8  LI... +268.0
CAPE... +1913.7  CIN... -257.1             | CAPE... +2248.4  CIN... -56.7
                                           |
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 -66.5 -87.7  295  26 13   0.3   0.1 | -66.7 -88.1  290  25 13   1.5   0.8
 45000 -63.2 -81.8  285  40 21   6.1   3.3 | -62.3 -80.1  290  41 21   5.7   3.1
 40000 -54.0 -65.2  270  30 15   6.6   3.6 | -53.6 -64.5  275  33 17   6.8   3.7
 38000 -50.0 -58.0  270  28 15   6.6   3.6 | -49.5 -57.1  275  31 16   6.8   3.7
 36000 -46.1 -51.0  270  27 14   6.7   3.7 | -45.4 -49.7  275  29 15   6.9   3.8
 34000 -41.6 -42.9  270  24 12   7.7   4.2 | -40.9 -41.6  270  26 14   7.5   4.1
 32000 -37.0 -34.6  270  21 11   7.5   4.1 | -35.9 -32.6  265  23 12   7.8   4.3
 30000 -31.3 -24.3  255  16  8   8.5   4.7 | -31.0 -23.8  250  21 11   8.2   4.5
 29000 -28.7 -19.7  245  14  7   8.5   4.7 | -28.5 -19.3  240  20 10   8.1   4.5
 28000 -26.2 -15.2  240  13  7   7.9   4.3 | -26.3 -15.3  235  20 10   6.4   3.5
 27000 -23.9 -11.0  240  13  7   7.9   4.3 | -24.3 -11.7  240  20 11   6.6   3.6
 26000 -21.5  -6.7  235  12  6   7.9   4.3 | -22.3  -8.1  240  21 11   6.6   3.6
 25000 -19.1  -2.4  235  12  6   7.3   4.0 | -20.3  -4.5  240  22 11   7.3   4.0
 24000 -17.0   1.4  245  16  8   7.1   3.9 | -18.1  -0.6  250  25 13   7.7   4.2
 23000 -14.9   5.2  250  20 10   7.1   3.9 | -15.9   3.4  260  28 14   7.8   4.3
 22000 -12.7   9.1  250  23 12   8.2   4.5 | -13.5   7.7  265  31 16   9.3   5.1
 21000 -10.3  13.5  250  21 11   8.4   4.6 | -10.7  12.7  265  30 15   9.4   5.2
 20000  -7.8  18.0  250  20 10   8.5   4.7 |  -7.8  18.0  270  29 15   9.4   5.2
 19500  -6.6  20.1  250  20 10   8.8   4.8 |  -6.4  20.5  270  29 15   9.2   5.0
 19000  -5.2  22.6  245  19 10   9.4   5.2 |  -5.0  23.0  270  28 14   8.7   4.8
 18500  -3.9  25.0  245  18  9   9.5   5.2 |  -3.7  25.3  270  26 14   8.7   4.8
 18000  -2.5  27.5  245  17  9   9.1   5.0 |  -2.4  27.7  270  25 13   8.9   4.9
 17500  -1.2  29.8  245  15  8   9.1   5.0 |  -1.0  30.2  270  23 12   8.9   4.9
 17000   0.1  32.2  240  14  7   9.1   5.0 |   0.3  32.5  265  21 11   8.8   4.8
 16500   1.4  34.5  245  13  7   8.9   4.9 |   1.6  34.9  265  20 10   8.6   4.7
 16000   2.7  36.9  245  12  6   8.9   4.9 |   2.8  37.0  265  19 10   8.6   4.7
 15500   4.1  39.4  245  11  6   9.5   5.2 |   4.7  40.5  265  17  9   8.7   4.8
 15000   6.2  43.2  255  10  5   9.4   5.2 |   6.0  42.8  270  17  9   8.8   4.8
 14500   7.6  45.7  260  11  5   9.2   5.1 |   7.3  45.1  270  16  8   9.1   5.0
 14000   9.0  48.2  265  12  6   9.3   5.1 |   8.6  47.5  270  15  8   9.1   5.0
 13500  10.4  50.7  270  13  6   8.9   4.9 |   9.9  49.8  275  14  7   9.2   5.1
 13000  11.7  53.1  275  14  7   9.0   4.9 |  11.3  52.3  275  14  7   9.3   5.1
 12500  13.1  55.6  280  15  8   9.0   4.9 |  12.6  54.7  280  13  7   9.2   5.1
 12000  14.5  58.1  285  16  8   9.2   5.0 |  14.0  57.2  280  12  6   9.4   5.2
 11750  15.2  59.4  285  16  8   9.2   5.0 |  14.7  58.5  280  12  6   9.4   5.2
 11500  15.9  60.6  285  17  9   9.0   4.9 |  15.3  59.5  285  11  6  10.0   5.5
 11250  16.5  61.7  285  17  9   8.9   4.9 |  16.1  61.0  285  11  5   9.3   5.1
 11000  17.2  63.0  285  17  9   8.9   4.9 |  16.7  62.1  285  10  5   8.4   4.6
 10750  17.8  64.0  285  17  9   9.0   4.9 |  17.3  63.1  285  10  5   8.7   4.8
 10500  18.4  65.1  290  17  9   7.2   4.0 |  17.9  64.2  285   9  5   8.5   4.7
 10250  18.8  65.8  285  17  9   5.8   3.2 |  18.4  65.1  285   9  4   8.5   4.7
 10000  19.2  66.6  285  17  9   6.6   3.6 |  19.0  66.2  280   8  4   8.0   4.4
  9750  19.7  67.5  285  17  9   7.9   4.3 |  19.5  67.1  275   7  4   7.6   4.2
  9500  20.0  68.0  280  16  8  -1.1  -0.6 |  19.9  67.8  270   7  3   3.8   2.1
  9250  19.3  66.7  275  16  8  -7.7  -4.2 |  19.8  67.6  255   7  3   0.2   0.1
  9000  18.6  65.5  265  15  8  -6.2  -3.4 |  19.7  67.5  240   7  3   3.7   2.1
  8750  17.8  64.0  255  15  8  -9.3  -5.1 |  20.1  68.2  225   7  4  10.3   5.6
  8500  16.9  62.4  250  15  8  -4.2  -2.3 |  20.9  69.6  215   7  3  10.0   5.5
  8250  16.7  62.1  235  14  7   1.2   0.7 |  21.4  70.5  210   7  4   7.7   4.2
  8000  16.6  61.9  220  13  7  -1.6  -0.9 |  22.0  71.6  200   7  4   7.5   4.1
  7750  16.5  61.7  205  13  7   4.9   2.7 |  22.5  72.5  195   8  4  10.5   5.8
  7500  17.1  62.8  195  13  7  10.7   5.8 |  23.4  74.1  190   8  4  12.9   7.1
  7250  17.8  64.0  195  12  6   8.2   4.5 |  24.2  75.6  190   8  4  11.0   6.0
  7000  18.4  65.1  190  12  6  10.6   5.8 |  25.1  77.2  185   8  4  12.7   7.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/23/2015 at 1500 MDT          |       06/23/2015 at 1800 MDT
                                           |
K index... +30.8  LI... +264.7             | K index... +32.2  LI... +270.1
CAPE... +3397.6  CIN... -39.0              | CAPE... +952.0  CIN... -19.2
                                           |
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 -67.2 -89.0  285  27 14   2.2   1.2 | -67.4 -89.3  285  31 16   2.1   1.1
 45000 -62.3 -80.1  285  38 20   5.3   2.9 | -62.8 -81.0  280  37 19   4.6   2.5
 40000 -53.8 -64.8  280  41 21   7.7   4.2 | -55.0 -67.0  265  33 17   8.7   4.8
 38000 -49.2 -56.6  275  36 19   7.7   4.2 | -49.8 -57.6  255  33 17   8.7   4.8
 36000 -44.6 -48.3  270  32 16   7.7   4.2 | -44.6 -48.3  245  34 18   8.6   4.7
 34000 -40.0 -40.0  265  31 16   7.7   4.2 | -39.4 -38.9  250  34 18   8.5   4.7
 32000 -34.8 -30.6  255  30 16   8.3   4.5 | -33.7 -28.7  255  34 18   8.9   4.9
 30000 -29.9 -21.8  250  30 15   8.1   4.4 | -29.0 -20.2  265  32 16   7.8   4.3
 29000 -27.5 -17.5  245  30 15   8.1   4.4 | -26.7 -16.1  270  31 16   7.8   4.3
 28000 -25.2 -13.4  245  30 15   6.2   3.4 | -24.4 -11.9  275  30 15   7.7   4.3
 27000 -23.4 -10.1  250  29 15   6.4   3.5 | -22.1  -7.8  275  29 15   7.8   4.3
 26000 -21.5  -6.7  260  29 15   6.4   3.5 | -19.8  -3.6  275  27 14   7.8   4.3
 25000 -19.6  -3.3  265  30 15   7.5   4.1 | -17.5   0.5  280  25 13   7.3   4.0
 24000 -17.2   1.0  270  30 15   7.9   4.3 | -15.4   4.3  285  23 12   7.1   3.9
 23000 -14.9   5.2  270  30 15   7.9   4.4 | -13.4   7.9  290  21 11   7.1   3.9
 22000 -12.6   9.3  275  30 15   7.7   4.2 | -11.3  11.7  295  19 10   6.7   3.7
 21000 -10.4  13.3  275  27 14   7.7   4.2 |  -9.4  15.1  295  17  9   6.6   3.6
 20000  -8.1  17.4  280  24 12   7.8   4.3 |  -7.5  18.5  300  16  8   6.6   3.6
 19500  -7.0  19.4  280  23 12   8.0   4.4 |  -6.5  20.3  300  16  8   6.6   3.6
 19000  -5.8  21.6  280  21 11   8.5   4.7 |  -5.6  21.9  300  15  8   6.5   3.6
 18500  -4.6  23.7  280  19 10   8.4   4.6 |  -4.7  23.5  300  13  7   6.5   3.6
 18000  -3.3  26.1  280  17  9   9.6   5.2 |  -3.7  25.3  300  12  6   6.8   3.7
 17500  -1.8  28.8  280  17  9   9.7   5.3 |  -2.7  27.1  295  12  6   6.9   3.8
 17000  -0.4  31.3  280  16  8   9.7   5.3 |  -1.7  28.9  295  11  6   6.9   3.8
 16500   1.1  34.0  275  15  8   9.7   5.3 |  -0.8  30.6  290  10  5   6.6   3.6
 16000   2.5  36.5  275  15  8   9.7   5.3 |   0.2  32.4  285  10  5   6.3   3.5
 15500   4.7  40.5  275  14  7   9.6   5.3 |   2.1  35.8  270   9  5  10.0   5.5
 15000   6.1  43.0  275  13  7   9.6   5.3 |   3.6  38.5  265   9  5  10.0   5.5
 14500   7.5  45.5  275  12  6   9.6   5.3 |   5.0  41.0  255   9  5   9.6   5.3
 14000   8.9  48.0  270  11  6   9.7   5.3 |   6.5  43.7  250  10  5   9.7   5.3
 13500  10.2  50.4  265   9  5   8.9   4.9 |   7.9  46.2  245  10  5   9.3   5.1
 13000  11.5  52.7  250   8  4   9.0   5.0 |   9.2  48.6  240  11  6   9.3   5.1
 12500  12.8  55.0  225   7  3   8.3   4.5 |  10.6  51.1  230  12  6   8.8   4.8
 12000  14.0  57.2  210   7  4   8.2   4.5 |  11.9  53.4  225  13  7   9.0   4.9
 11750  14.5  58.1  205   7  4   8.1   4.4 |  12.6  54.7  225  14  7   8.9   4.9
 11500  15.2  59.4  200   8  4   9.2   5.1 |  13.2  55.8  220  15  8  10.0   5.5
 11250  15.9  60.6  195   8  4   8.1   4.5 |  14.0  57.2  220  16  8   9.4   5.1
 11000  16.3  61.3  190   8  4   6.4   3.5 |  14.6  58.3  215  16  8   8.1   4.4
 10750  16.8  62.2  190   9  5   6.9   3.8 |  15.2  59.4  215  17  9   8.3   4.5
 10500  17.3  63.1  185  10  5   6.4   3.5 |  15.9  60.6  210  17  9   9.4   5.2
 10250  17.6  63.7  185  10  5   6.2   3.4 |  16.6  61.9  210  18  9  10.5   5.8
 10000  18.0  64.4  185  11  6   7.1   3.9 |  17.4  63.3  205  19 10   9.3   5.1
  9750  18.5  65.3  180  13  6   8.0   4.4 |  18.0  64.4  205  20 10   8.6   4.7
  9500  18.9  66.0  180  14  7   6.3   3.5 |  18.6  65.5  200  20 11   9.2   5.1
  9250  19.1  66.4  180  14  7   4.7   2.6 |  19.3  66.7  200  21 11   9.6   5.2
  9000  19.4  66.9  180  15  8   6.2   3.4 |  20.0  68.0  200  22 11   9.3   5.1
  8750  19.8  67.6  180  15  8   8.6   4.7 |  20.7  69.3  195  23 12   8.9   4.9
  8500  20.5  68.9  175  15  8  10.2   5.6 |  21.3  70.3  195  24 12   8.8   4.8
  8250  21.2  70.2  175  15  8  10.7   5.9 |  22.0  71.6  195  24 12   8.7   4.8
  8000  22.0  71.6  175  15  8  10.0   5.5 |  22.6  72.7  190  24 12   9.1   5.0
  7750  22.8  73.0  175  15  8  12.4   6.8 |  23.2  73.8  190  24 12   7.6   4.2
  7500  23.7  74.7  175  15  8  13.1   7.2 |  23.5  74.3  190  22 12   3.7   2.0
  7250  24.6  76.3  175  15  8  10.8   5.9 |  23.6  74.5  190  20 10   2.2   1.2
  7000  25.4  77.7  170  14  7  12.8   7.0 |  23.7  74.7  190  17  9   3.3   1.8
  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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