Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 031053
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0453 MDT Monday, August 3, 2015

This forecast is for Monday, August 3, 2015:

If the trigger temperature of 70.4 F/21.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 460 ft/min (2.3 m/s)
   Maximum height of thermals.................. 16150 ft MSL (9392 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ 1100 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................. 11342 ft MSL (4585 ft AGL)
Thermal soaring outlook for Tuesday 08/04...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:01:29 / 20:09:13 MDT
Total possible sunshine........... 14 hr 7 min 44 sec (847 min 44 sec)
Altitude of sun at 13:05:07 MDT... 68.46 degrees

Upper air data from numerical model forecast valid on 08/03/2015 at 0600 MDT

Freezing level.................. 15391 ft MSL (8633 ft AGL)
Convective condensation level... 13395 ft MSL (6637 ft AGL)
Lifted condensation level....... 13351 ft MSL (6593 ft AGL)
Lifted index.................... -2.3
K index......................... +23.5

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  -66.4 -87.5   275   36   18   2.5   1.4      M     M       M      M    M
 45000  -60.4 -76.7   270   50   26   7.2   4.0      M     M       M      M    M
 40000  -49.5 -57.1   270   44   22   5.2   2.9      M     M       M      M    M
 38000  -46.4 -51.5   260   37   19   5.3   2.9      M     M       M      M    M
 36000  -43.2 -45.8   250   32   16   6.2   3.4      M     M       M      M    M
 34000  -38.0 -36.4   245   26   14   8.9   4.9      M     M       M      M    M
 32000  -32.7 -26.9   240   21   11   8.8   4.8      M     M       M      M    M
 30000  -27.8 -18.0   235   19   10   8.1   4.4   43.1 109.6    13.9      M    M
 29000  -25.4 -13.7   230   19   10   8.1   4.5   42.5 108.5    13.6      M    M
 28000  -23.0  -9.4   225   19   10   7.7   4.2   42.1 107.7    13.3      M    M
 27000  -20.4  -4.7   220   17    9   7.3   4.0   40.7 105.3    12.4      M    M
 26000  -18.2  -0.8   210   17    9   7.3   4.0   39.8 103.7    11.8      M    M
 25000  -16.1   3.0   205   16    8   7.2   3.9   39.1 102.3    11.2      M    M
 24000  -14.1   6.6   190   16    8   6.8   3.8   37.9 100.3    10.4      M    M
 23000  -12.1  10.2   175   16    8   6.9   3.8   36.9  98.4     9.6      M    M
 22000  -10.1  13.8   165   17    9   4.7   2.6   36.0  96.7     8.8      M    M
 21000   -9.8  14.4   150   18    9   0.3   0.2   32.7  90.9     6.2      M    M
 20000   -9.7  14.5   135   19   10   0.3   0.1   29.5  85.1     3.5      M    M
 19500   -9.6  14.7   130   20   10  -0.6  -0.3   27.9  82.3     2.2      M    M
 19000   -9.0  15.8   130   21   11   9.5   5.2   27.0  80.6     1.4      M    M
 18500   -7.6  18.3   130   22   11   9.2   5.0   26.9  80.4     1.3      M    M
 18000   -6.2  20.8   135   23   12   8.8   4.8   26.8  80.3     1.2      M    M
 17500   -5.1  22.8   130   23   12   8.1   4.4   26.5  79.8     0.9      M    M
 17000   -3.9  25.0   130   24   12   8.1   4.5   26.3  79.3     0.6      M    M
 16500   -2.8  27.0   130   24   12   7.9   4.3   26.0  78.8     0.3      M    M
 16000   -1.7  28.9   130   24   12   7.9   4.4   25.7  78.2    -0.0    854  4.3
 15500   -0.6  30.9   130   24   12   8.5   4.7   25.4  77.7    -0.4    805  4.1
 15000    0.8  33.4   130   25   13   8.9   4.9   25.2  77.4    -0.5    751  3.8
 14500    2.1  35.8   130   25   13   8.9   4.9   25.1  77.2    -0.6    696  3.5
 14000    4.2  39.6   135   26   13   8.9   4.9   24.9  76.8    -0.7    611  3.1
 13500    5.6  42.1   135   27   14   8.1   4.4   24.8  76.6    -0.7    554  2.8
 13000    6.6  43.9   140   25   13   7.6   4.2   24.4  75.9    -1.2    509  2.6
 12500    7.6  45.7   145   23   12   7.2   4.0   24.1  75.4    -1.6    463  2.4
 12000    8.5  47.3   145   22   11   7.3   4.0   23.6  74.5    -2.3    423  2.1
 11750    8.9  48.0   150   21   11   7.4   4.1   23.4  74.2    -2.6    403  2.0
 11500    9.3  48.7   150   20   10   7.6   4.1   23.3  73.9    -2.9    383  1.9
 11250    9.8  49.6   155   19   10   7.8   4.3   23.1  73.6    -3.2    362  1.8
 11000   10.3  50.5   160   18    9   8.1   4.4   23.0  73.3    -3.4    339  1.7
 10750   10.8  51.4   160   17    9   8.2   4.5   22.8  73.1    -3.6    316  1.6
 10500   11.4  52.5   165   16    8   8.1   4.4   22.7  72.9    -3.8    293  1.5
 10250   11.9  53.4   170   15    8   7.7   4.2   22.6  72.6    -4.0    269  1.4
 10000   12.5  54.5   170   15    7   8.0   4.4   22.4  72.4    -4.2    245  1.2
  9750   13.1  55.6   175   14    7   8.7   4.8   22.3  72.2    -4.3    219  1.1
  9500   13.7  56.7   180   13    7   7.9   4.4   22.2  72.0    -4.4    193  1.0
  9250   14.3  57.7   185   12    6   6.8   3.7   22.0  71.7    -4.6    169  0.9
  9000   14.8  58.6   185   11    5   6.9   3.8   21.8  71.3    -4.8    146  0.7
  8750   15.4  59.7   185   10    5   9.7   5.3   21.7  71.0    -4.9    120  0.6
  8500   16.2  61.2   190    9    5   8.1   4.4   21.7  71.1    -4.9     90  0.5
  8250   16.6  61.9   185    8    4   4.8   2.6   21.4  70.5    -5.2     70  0.4
  8000   16.9  62.4   185    7    3   4.4   2.4   21.0  69.8    -5.6     53  0.3
  7750   17.2  63.0   185    6    3   6.9   3.8   20.7  69.2    -6.0     35  0.2
  7500   17.7  63.9   195    4    2   2.1   1.2   20.5  68.8    -6.3     14  0.1
  7250   17.5  63.5   205    3    2  -5.4  -3.0   19.9  67.8    -6.9     14  0.1
  7000   17.3  63.1   220    2    1   0.5   0.3   19.3  66.8    -7.4     13  0.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/03/2015 at 0900 MDT          |       08/03/2015 at 1200 MDT
                                           |
K index... +22.5  LI... +270.8             | K index... +27.5  LI... +270.7
CAPE... +444.4  CIN... -23.6               | CAPE... +409.9  CIN... M
                                           |
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 -67.1 -88.8  270  36 18   2.2   1.2 | -66.5 -87.7  265  33 17   2.0   1.1
 45000 -60.8 -77.4  265  52 27   8.3   4.5 | -60.5 -76.9  260  47 24   7.9   4.4
 40000 -48.5 -55.3  265  44 23   5.3   2.9 | -48.6 -55.5  255  48 25   5.7   3.1
 38000 -45.4 -49.7  260  36 18   5.3   2.9 | -45.2 -49.4  250  41 21   5.7   3.1
 36000 -42.2 -44.0  250  27 14   5.8   3.2 | -41.8 -43.2  240  34 18   6.1   3.4
 34000 -37.7 -35.9  250  21 11   7.6   4.2 | -37.3 -35.1  240  27 14   7.6   4.1
 32000 -33.2 -27.8  245  15  8   7.3   4.0 | -32.8 -27.0  230  20 10   7.3   4.0
 30000 -28.0 -18.4  235  16  8   9.0   4.9 | -28.0 -18.4  230  18  9   8.1   4.5
 29000 -25.3 -13.5  235  17  9   9.0   4.9 | -25.0 -13.0  230  18  9   8.2   4.5
 28000 -22.1  -7.8  230  18  9   6.6   3.6 | -22.7  -8.9  230  18  9   6.9   3.8
 27000 -20.1  -4.2  230  18  9   6.9   3.8 | -20.6  -5.1  230  17  9   7.0   3.9
 26000 -18.1  -0.6  230  18  9   7.0   3.8 | -18.6  -1.5  235  17  9   7.1   3.9
 25000 -16.0   3.2  230  18  9   6.8   3.7 | -16.5   2.3  240  17  9   6.9   3.8
 24000 -14.2   6.4  230  19 10   6.4   3.5 | -14.6   5.7  240  16  8   6.6   3.6
 23000 -12.3   9.9  230  19 10   6.4   3.5 | -12.7   9.1  240  15  8   6.6   3.6
 22000 -10.5  13.1  230  20 10   6.1   3.3 | -10.8  12.6  240  14  7   6.3   3.4
 21000  -8.9  16.0  210  17  9   5.4   3.0 |  -9.1  15.6  230  13  7   5.6   3.1
 20000  -7.4  18.7  180  18  9   5.5   3.0 |  -7.5  18.5  215  14  7   5.7   3.1
 19500  -6.6  20.1  170  20 10   5.9   3.3 |  -6.7  19.9  210  14  7   5.9   3.2
 19000  -6.1  21.0  165  22 11   0.7   0.4 |  -5.9  21.4  200  15  8   3.7   2.1
 18500  -6.0  21.2  155  22 11   0.8   0.5 |  -5.4  22.3  185  17  9   3.8   2.1
 18000  -5.8  21.6  150  23 12   1.7   1.0 |  -4.9  23.2  175  20 10   4.2   2.3
 17500  -5.3  22.5  145  23 12   4.1   2.2 |  -4.2  24.4  170  21 11   5.1   2.8
 17000  -4.7  23.5  145  23 12   3.9   2.1 |  -3.4  25.9  165  22 11   4.9   2.7
 16500  -4.0  24.8  140  23 12   5.5   3.0 |  -2.6  27.3  165  22 12   6.6   3.6
 16000  -3.1  26.4  140  23 12   5.6   3.1 |  -1.6  29.1  165  22 11   6.6   3.6
 15500  -2.3  27.9  140  23 12   7.8   4.3 |  -0.6  30.9  160  21 11   6.8   3.7
 15000  -0.9  30.4  145  23 12   9.4   5.1 |   0.4  32.7  160  21 11   7.0   3.8
 14500   0.6  33.1  145  24 12   9.8   5.4 |   1.8  35.2  155  20 10   6.7   3.7
 14000   3.0  37.4  145  24 12  10.7   5.9 |   2.8  37.0  155  20 10   6.7   3.7
 13500   4.6  40.3  145  24 13  10.3   5.7 |   3.7  38.7  155  20 10   6.8   3.7
 13000   6.1  43.0  145  24 12  10.0   5.5 |   4.7  40.5  155  19 10   6.8   3.7
 12500   7.6  45.7  150  23 12   9.4   5.2 |   5.7  42.3  155  18  9   6.7   3.7
 12000   8.7  47.7  150  22 11   8.2   4.5 |   6.6  43.9  155  17  9   7.0   3.8
 11750   9.2  48.6  150  21 11   8.7   4.8 |   7.0  44.6  155  16  8   6.6   3.6
 11500   9.8  49.6  150  20 10   7.6   4.2 |   7.5  45.5  155  15  8   8.1   4.4
 11250  10.1  50.2  155  19 10   6.5   3.5 |   8.1  46.6  155  14  7   9.6   5.3
 11000  10.5  50.9  155  18  9   6.9   3.8 |   8.8  47.8  155  14  7   9.3   5.1
 10750  10.9  51.6  155  16  8   7.1   3.9 |   9.4  48.9  150  13  7   9.3   5.1
 10500  11.3  52.3  160  15  8   6.9   3.8 |  10.1  50.2  150  13  6   9.2   5.1
 10250  11.7  53.1  160  14  7   6.0   3.3 |  10.7  51.3  150  12  6   8.8   4.9
 10000  12.1  53.8  165  12  6   6.7   3.7 |  11.4  52.5  150  12  6   9.8   5.4
  9750  12.6  54.7  170  11  6   7.6   4.2 |  12.2  54.0  150  12  6  10.9   6.0
  9500  13.2  55.8  175  10  5   7.3   4.0 |  13.0  55.4  150  12  6  10.2   5.6
  9250  13.7  56.7  175   9  5   7.1   3.9 |  13.7  56.7  150  12  6   9.5   5.2
  9000  14.2  57.6  180   9  4   7.4   4.0 |  14.4  57.9  155  12  6   9.6   5.3
  8750  14.8  58.6  185   8  4   8.9   4.9 |  15.1  59.2  155  12  6  10.7   5.9
  8500  15.5  59.9  185   8  4   9.1   5.0 |  15.9  60.6  155  11  6  10.9   6.0
  8250  16.1  61.0  185   7  4   8.5   4.7 |  16.7  62.1  155  11  6  10.7   5.9
  8000  16.7  62.1  185   7  3   8.4   4.6 |  17.5  63.5  155  11  6  10.5   5.8
  7750  17.4  63.3  180   6  3   9.2   5.0 |  18.3  64.9  155  11  6  11.3   6.2
  7500  18.1  64.6  180   5  3   9.0   4.9 |  19.2  66.6  155  11  6  12.9   7.1
  7250  18.6  65.5  175   5  2   7.8   4.3 |  20.1  68.2  155  11  5  13.3   7.3
  7000  19.2  66.6  175   4  2   8.8   4.8 |  21.1  70.0  150  10  5  13.1   7.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/03/2015 at 1500 MDT          |       08/03/2015 at 1800 MDT
                                           |
K index... +29.1  LI... +270.5             | K index... +27.1  LI... +269.3
CAPE... +486.0  CIN... -2.1                | CAPE... +915.6  CIN... -3.8
                                           |
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 -66.4 -87.5  260  33 17   1.9   1.1 | -65.5 -85.9  250  28 14   1.7   0.9
 45000 -61.0 -77.8  255  48 25   7.0   3.8 | -60.5 -76.9  245  45 23   6.7   3.7
 40000 -49.9 -57.8  250  39 20   7.5   4.1 | -49.9 -57.8  250  44 23   7.0   3.9
 38000 -45.5 -49.9  250  26 13   7.4   4.1 | -45.6 -50.1  245  30 15   7.0   3.9
 36000 -41.0 -41.8  255  13  7   7.7   4.2 | -41.4 -42.5  225  16  8   7.2   4.0
 34000 -36.1 -33.0  255  13  7   8.3   4.5 | -36.7 -34.1  225  16  8   7.9   4.3
 32000 -31.1 -24.0  250  14  7   8.1   4.4 | -32.0 -25.6  220  17  9   7.8   4.3
 30000 -26.7 -16.1  250  16  8   7.3   4.0 | -27.7 -17.9  235  19 10   7.0   3.8
 29000 -24.0 -11.2  250  17  9   7.3   4.0 | -25.6 -14.1  245  20 10   7.0   3.9
 28000 -21.9  -7.4  250  18  9   6.7   3.7 | -23.0  -9.4  255  22 11   7.0   3.8
 27000 -19.9  -3.8  250  19 10   6.8   3.7 | -21.0  -5.8  255  23 12   7.0   3.9
 26000 -17.9  -0.2  250  20 10   6.8   3.7 | -18.9  -2.0  255  24 12   7.0   3.9
 25000 -15.9   3.4  255  20 11   6.7   3.7 | -16.8   1.8  260  25 13   6.9   3.8
 24000 -14.0   6.8  255  20 10   6.6   3.6 | -14.9   5.2  265  25 13   6.4   3.5
 23000 -12.1  10.2  255  19 10   6.6   3.6 | -12.9   8.8  275  25 13   6.4   3.5
 22000 -10.2  13.6  255  18  9   6.3   3.4 | -11.0  12.2  280  25 13   6.3   3.5
 21000  -8.6  16.5  250  17  9   5.5   3.0 |  -9.2  15.4  285  26 14   6.0   3.3
 20000  -7.0  19.4  245  15  8   5.5   3.0 |  -7.5  18.5  285  27 14   6.1   3.3
 19500  -6.2  20.8  240  15  8   5.6   3.1 |  -6.7  19.9  290  28 14   6.1   3.4
 19000  -5.4  22.3  235  14  7   4.8   2.6 |  -5.8  21.6  290  28 14   5.4   3.0
 18500  -4.8  23.4  230  13  7   4.8   2.6 |  -5.1  22.8  290  28 14   5.4   3.0
 18000  -4.1  24.6  225  13  7   4.7   2.6 |  -4.3  24.3  295  28 14   5.5   3.0
 17500  -3.4  25.9  220  12  6   4.4   2.4 |  -3.5  25.7  295  28 14   5.6   3.1
 17000  -2.8  27.0  215  12  6   4.4   2.4 |  -2.8  27.0  295  28 14   5.5   3.0
 16500  -2.2  28.0  210  12  6   4.8   2.6 |  -1.9  28.6  290  28 14   6.5   3.6
 16000  -1.5  29.3  205  12  6   4.8   2.7 |  -1.0  30.2  285  27 14   6.6   3.6
 15500  -0.8  30.6  200  12  6   4.7   2.6 |  -0.1  31.8  285  26 14   6.8   3.7
 15000  -0.1  31.8  195  12  6   4.6   2.5 |   0.9  33.6  280  25 13   7.1   3.9
 14500   1.0  33.8  185  13  6   7.8   4.3 |   1.9  35.4  275  23 12   7.1   3.9
 14000   2.2  36.0  185  13  7   8.7   4.8 |   3.3  37.9  270  19 10   6.6   3.6
 13500   3.5  38.3  180  14  7   7.7   4.2 |   4.3  39.7  265  17  9   6.8   3.8
 13000   4.4  39.9  175  14  7   6.8   3.7 |   5.2  41.4  255  14  7   7.0   3.9
 12500   5.4  41.7  175  15  8   7.0   3.9 |   6.2  43.2  245  13  6   6.3   3.5
 12000   6.4  43.5  175  14  7   7.2   4.9 |   7.1  44.8  240  11  6   7.0   3.9
 11750   6.9  44.4  175  14  7   7.0   3.9 |   7.6  45.7  235  10  5   6.8   3.7
 11500   7.4  45.3  175  14  7   7.8   4.3 |   8.1  46.6  230  10  5   6.8   3.7
 11250   8.0  46.4  175  13  7   7.9   4.3 |   8.6  47.5  230   9  5   6.9   3.8
 11000   8.5  47.3  175  13  7   6.7   3.7 |   9.1  48.4  225   8  4   7.2   3.9
 10750   8.9  48.0  175  13  6   6.5   3.5 |   9.6  49.3  220   8  4   7.1   3.9
 10500   9.4  48.9  175  12  6   6.9   3.8 |  10.1  50.2  215   7  4   7.3   4.0
 10250   9.9  49.8  175  12  6   8.0   4.4 |  10.6  51.1  210   7  3   8.0   4.4
 10000  10.5  50.9  175  12  6   7.4   4.0 |  11.2  52.2  210   6  3   7.8   4.3
  9750  10.9  51.6  175  11  6   6.4   3.5 |  11.7  53.1  205   6  3   7.6   4.1
  9500  11.4  52.5  175  11  6   6.7   3.7 |  12.2  54.0  195   5  3   7.2   4.0
  9250  11.8  53.2  180  10  5   6.7   3.7 |  12.7  54.9  190   4  2   6.0   3.3
  9000  12.3  54.1  180  10  5   6.9   3.8 |  13.1  55.6  175   2  1   6.4   3.5
  8750  12.8  55.0  185   9  5   7.4   4.1 |  13.6  56.5  090   1  0  10.4   5.7
  8500  13.3  55.9  185   8  4   7.9   4.3 |  14.4  57.9  045   2  1  10.4   5.7
  8250  13.9  57.0  190   7  4   8.2   4.5 |  15.0  59.0  035   3  2   7.8   4.3
  8000  14.4  57.9  200   6  3   7.8   4.3 |  15.5  59.9  035   5  2   7.4   4.0
  7750  15.0  59.0  210   5  3   9.1   5.0 |  16.0  60.8  030   6  3   9.5   5.2
  7500  15.6  60.1  220   4  2   8.1   4.4 |  16.8  62.2  030   6  3  10.0   5.5
  7250  16.1  61.0  220   4  2   5.5   3.0 |  17.4  63.3  030   6  3   7.8   4.3
  7000  16.5  61.7  220   4  2   7.6   4.1 |  18.0  64.4  035   6  3   9.7   5.3
  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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