Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 241443
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0842 MDT Wednesday, August 24, 2016

This forecast is for Wednesday, August 24, 2016:

If the trigger temperature of 62.1 F/16.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8356 ft MSL (1598 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1415 MDT
Time of overdevelopment........................ None
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................. None
Thermal soaring outlook for Thursday 08/25..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:21:09 / 19:41:48 MDT
Total possible sunshine........... 13 hr 20 min 39 sec (800 min 39 sec)
Altitude of sun at 13:01:05 MDT... 61.79 degrees

Upper air data from numerical model forecast valid on 08/24/2016 at 0600 MDT

Freezing level.................. 13579 ft MSL (6821 ft AGL)
Convective condensation level... 13208 ft MSL (6450 ft AGL)
Lifted condensation level....... 11732 ft MSL (4975 ft AGL)
Lifted index.................... +1.5
K index......................... +26.4

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  -59.0 -74.2   230   33   17   1.9   1.1      M     M       M      M    M
 45000  -55.7 -68.3   225   46   24   2.6   1.4      M     M       M      M    M
 40000  -51.7 -61.1   220   54   28   2.7   1.5      M     M       M      M    M
 38000  -50.1 -58.2   220   41   21   2.7   1.5      M     M       M      M    M
 36000  -48.5 -55.3   225   28   15   2.8   1.5      M     M       M      M    M
 34000  -44.4 -47.9   225   20   11   8.7   4.8      M     M       M      M    M
 32000  -39.2 -38.6   225   15    8   8.7   4.8      M     M       M      M    M
 30000  -33.7 -28.7   225   13    7   7.9   4.4   36.1  97.1    15.5      M    M
 29000  -31.4 -24.5   225   13    7   8.0   4.4   35.5  95.9    15.1      M    M
 28000  -29.0 -20.2   225   13    7   7.8   4.3   34.9  94.9    14.9      M    M
 27000  -26.8 -16.2   230   13    7   7.4   4.1   34.0  93.2    14.2      M    M
 26000  -24.6 -12.3   230   12    6   7.4   4.1   33.1  91.5    13.6      M    M
 25000  -22.4  -8.3   230   12    6   7.4   4.1   32.3  90.1    13.1      M    M
 24000  -20.3  -4.5   235   11    6   7.1   3.9   31.3  88.4    12.5      M    M
 23000  -18.2  -0.8   235   11    5   7.1   3.9   30.4  86.7    11.7      M    M
 22000  -16.1   3.0   240   10    5   7.2   4.0   29.5  85.1    11.1      M    M
 21000  -14.1   6.6   240   11    6   6.5   3.6   28.4  83.1    10.2      M    M
 20000  -12.2  10.0   235   12    6   6.5   3.6   27.3  81.1     9.3      M    M
 19500  -11.3  11.7   235   12    6   6.6   3.6   26.8  80.2     8.9      M    M
 19000  -10.3  13.5   235   13    7   6.1   3.3   26.2  79.2     8.4      M    M
 18500   -9.5  14.9   230   13    7   5.8   3.2   25.5  78.0     7.8      M    M
 18000   -8.7  16.3   225   14    7   5.8   3.2   24.9  76.8     7.2      M    M
 17500   -7.8  18.0   220   15    8   6.2   3.4   24.2  75.6     6.7      M    M
 17000   -6.9  19.6   215   15    8   6.1   3.4   23.6  74.5     6.1      M    M
 16500   -6.1  21.0   210   16    8   6.2   3.4   23.0  73.5     5.6      M    M
 16000   -5.2  22.6   205   15    8   6.3   3.4   22.4  72.4     5.0      M    M
 15500   -4.3  24.3   205   15    7   6.5   3.5   21.9  71.4     4.5      M    M
 15000   -2.8  27.0   190   14    7   6.9   3.8   21.2  70.1     3.8      M    M
 14500   -1.8  28.8   180   14    7   7.2   4.0   20.7  69.3     3.4      M    M
 14000   -0.7  30.7   175   14    7   7.4   4.0   20.3  68.6     3.0      M    M
 13500    0.4  32.7   170   14    7   7.1   3.9   20.0  68.0     2.7      M    M
 13000    1.4  34.5   165   11    6   6.7   3.7   19.5  67.1     2.2      M    M
 12500    2.4  36.3   160    9    4   6.0   3.3   19.0  66.3     1.8      M    M
 12000    3.3  37.9   145    6    3   6.9   3.8   18.5  65.2     1.3      M    M
 11750    3.8  38.8   140    6    3   6.4   3.5   18.2  64.8     1.1      M    M
 11500    4.4  39.9   125    5    3   7.6   4.2   18.0  64.4     0.8      M    M
 11250    5.0  41.0   120    5    3   9.2   5.0   17.9  64.2     0.8      M    M
 11000    5.7  42.3   110    6    3   8.6   4.7   17.8  64.1     0.7      M    M
 10750    6.2  43.2   105    7    3   7.9   4.3   17.7  63.9     0.6      M    M
 10500    6.8  44.2   105    8    4   8.9   4.9   17.6  63.7     0.4      M    M
 10250    7.6  45.7   100    8    4  11.2   6.1   17.6  63.7     0.4      M    M
 10000    8.4  47.1   100    9    5  10.5   5.7   17.7  63.9     0.5      M    M
  9750    9.0  48.2   100   10    5   8.8   4.8   17.7  63.9     0.4      M    M
  9500    9.7  49.5   100   10    5   9.0   4.9   17.6  63.7     0.3      M    M
  9250   10.3  50.5   100   11    5   9.0   5.0   17.6  63.6     0.3      M    M
  9000   11.0  51.8   100   11    5   8.9   4.9   17.5  63.5     0.2      M    M
  8750   11.7  53.1   100   10    5  11.1   6.1   17.5  63.5     0.1      M    M
  8500   12.4  54.3   100    9    5   7.8   4.3   17.6  63.7     0.2      M    M
  8250   12.8  55.0   105    7    4   3.3   1.8   17.2  62.9    -0.2     47  0.2
  8000   13.1  55.6   110    5    2   4.2   2.3   16.7  62.1    -0.6     31  0.2
  7750   13.4  56.1   130    3    1   4.1   2.3   16.3  61.4    -1.1     14  0.1
  7500   13.6  56.5   170    1    1   2.2   1.2   16.0  60.7    -1.4      M    M
  7250   13.7  56.7   225    1    0   0.1   0.1   15.7  60.2    -1.7      M    M
  7000   13.7  56.7   275    1    1   1.7   0.9   15.4  59.6    -2.0      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/24/2016 at 0900 MDT          |       08/24/2016 at 1200 MDT
                                           |
K index... +24.5  LI... +273.1             | K index... +19.8  LI... +275.2
CAPE... +34.3  CIN... -18.8                | CAPE... 0.0  CIN... -0.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.5 -73.3  235  30 15   1.6   0.9 | -58.4 -73.1  230  32 16   1.9   1.0
 45000 -55.8 -68.4  225  47 24   1.9   1.1 | -55.8 -68.4  225  50 26   1.4   0.8
 40000 -52.8 -63.0  225  63 32   3.5   1.9 | -53.6 -64.5  220  66 34   3.9   2.1
 38000 -50.6 -59.1  230  45 23   3.7   2.0 | -51.1 -60.0  225  49 25   4.1   2.2
 36000 -48.4 -55.1  245  29 15   3.7   2.0 | -48.7 -55.7  230  33 17   4.1   2.3
 34000 -44.3 -47.7  255  21 11   8.4   4.6 | -44.4 -47.9  240  26 13   8.4   4.6
 32000 -38.6 -37.5  260  17  9   8.4   4.6 | -38.8 -37.8  255  24 12   8.3   4.5
 30000 -33.8 -28.8  260  16  8   7.9   4.3 | -33.7 -28.7  260  21 11   8.6   4.7
 29000 -31.5 -24.7  255  16  8   7.9   4.3 | -31.1 -24.0  260  20 10   8.6   4.7
 28000 -29.1 -20.4  250  16  8   7.8   4.3 | -28.6 -19.5  265  19 10   8.3   4.6
 27000 -26.8 -16.2  250  16  8   7.6   4.2 | -26.3 -15.3  260  17  9   7.7   4.2
 26000 -24.6 -12.3  250  15  8   7.6   4.2 | -24.0 -11.2  260  15  8   7.7   4.2
 25000 -22.3  -8.1  250  15  8   7.7   4.2 | -21.7  -7.1  255  13  7   7.9   4.3
 24000 -20.2  -4.4  245  15  8   6.8   3.7 | -19.6  -3.3  250  11  6   6.8   3.7
 23000 -18.2  -0.8  245  14  7   6.8   3.7 | -17.6   0.3  240  10  5   6.8   3.8
 22000 -16.2   2.8  245  13  7   6.8   3.8 | -15.6   3.9  230   8  4   6.9   3.8
 21000 -14.2   6.4  240  13  7   6.8   3.7 | -13.7   7.3  225   8  4   6.3   3.4
 20000 -12.2  10.0  240  13  7   6.9   3.8 | -11.9  10.6  215   9  5   6.3   3.5
 19500 -11.2  11.8  240  14  7   6.9   3.8 | -11.0  12.2  215   9  5   6.3   3.5
 19000 -10.3  13.5  235  14  7   6.5   3.5 | -10.0  14.0  215  10  5   6.1   3.3
 18500  -9.4  15.1  235  14  7   6.3   3.4 |  -9.2  15.4  210  11  6   6.0   3.3
 18000  -8.5  16.7  230  15  7   6.3   3.4 |  -8.3  17.1  210  12  6   6.0   3.3
 17500  -7.6  18.3  225  15  8   6.1   3.4 |  -7.5  18.5  210  13  7   5.7   3.1
 17000  -6.7  19.9  215  16  8   6.1   3.4 |  -6.7  19.9  205  14  7   5.8   3.2
 16500  -5.8  21.6  210  18  9   6.8   3.7 |  -5.9  21.4  200  16  8   4.5   2.4
 16000  -4.8  23.4  205  18  9   7.0   3.8 |  -5.0  23.0  185  18  9   3.9   2.2
 15500  -3.4  25.9  195  19 10   5.1   2.8 |  -4.3  24.3  180  19 10   5.7   3.1
 15000  -2.7  27.1  185  20 10   5.0   2.8 |  -3.5  25.7  175  19 10   5.8   3.2
 14500  -2.0  28.4  175  20 10   3.2   1.7 |  -2.7  27.1  165  18  9   4.7   2.6
 14000  -1.7  28.9  165  19 10   2.2   1.2 |  -2.0  28.4  165  16  8   4.4   2.4
 13500  -1.4  29.5  155  18  9   3.5   1.9 |  -1.4  29.5  160  15  8   5.2   2.9
 13000  -0.6  30.9  150  18  9   5.5   3.0 |  -0.4  31.3  155  14  7   6.2   3.4
 12500   0.2  32.4  145  17  9   8.2   4.5 |   0.6  33.1  150  13  7   8.2   4.5
 12000   1.7  35.1  145  17  9   8.8   4.8 |   2.0  35.6  145  11  5   8.0   4.4
 11750   2.4  36.3  145  17  9   9.2   5.1 |   2.6  36.7  140  10  5   8.3   4.6
 11500   3.1  37.6  145  17  9   9.4   5.1 |   3.2  37.8  135   9  5   8.7   4.8
 11250   3.8  38.8  140  17  9   9.6   5.3 |   3.9  39.0  130   9  4   9.4   5.1
 11000   4.5  40.1  140  17  9   9.2   5.0 |   4.5  40.1  130   8  4   9.1   5.0
 10750   5.2  41.4  135  17  9   9.0   4.9 |   5.2  41.4  125   8  4   9.0   4.9
 10500   5.8  42.4  135  17  9   9.1   5.0 |   5.9  42.6  125   8  4   9.2   5.1
 10250   6.5  43.7  130  17  9   9.4   5.2 |   6.6  43.9  125   8  4   9.4   5.2
 10000   7.2  45.0  125  16  8   8.8   4.8 |   7.2  45.0  125   8  4   9.7   5.3
  9750   7.8  46.0  120  16  8   7.9   4.3 |   8.0  46.4  125   7  4  10.1   5.5
  9500   8.4  47.1  120  16  8   7.6   4.2 |   8.7  47.7  125   7  4  10.1   5.5
  9250   8.9  48.0  115  15  8   7.2   4.0 |   9.5  49.1  125   7  4  10.1   5.5
  9000   9.4  48.9  105  14  7   7.3   4.0 |  10.2  50.4  125   7  4  10.1   5.5
  8750   9.9  49.8  100  14  7   7.7   4.2 |  11.0  51.8  125   7  4   9.8   5.4
  8500  10.5  50.9  090  13  6   7.5   4.1 |  11.7  53.1  125   7  4  10.4   5.7
  8250  10.9  51.6  085  11  6   7.3   4.0 |  12.5  54.5  125   7  4  10.9   6.0
  8000  11.4  52.5  080  10  5   6.8   3.8 |  13.3  55.9  125   7  4  10.8   5.9
  7750  11.9  53.4  070   9  4   9.0   5.0 |  14.1  57.4  125   7  3  10.9   6.0
  7500  12.6  54.7  065   8  4   8.0   4.4 |  14.9  58.8  125   7  3  11.1   6.1
  7250  13.0  55.4  065   7  4   4.4   2.4 |  15.7  60.3  125   7  3  11.2   6.1
  7000  13.3  55.9  065   7  4   7.4   4.0 |  16.6  61.9  125   6  3  11.1   6.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/24/2016 at 1500 MDT          |       08/24/2016 at 1800 MDT
                                           |
K index... +23.1  LI... +274.2             | K index... +18.9  LI... +274.7
CAPE... +67.5  CIN... -1.3                 | CAPE... 0.0  CIN... -0.1
                                           |
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 -58.7 -73.7  230  32 17   2.1   1.1 | -58.8 -73.8  230  34 17   2.1   1.2
 45000 -55.6 -68.1  225  50 26   1.7   0.9 | -55.9 -68.6  230  50 26   1.0   0.5
 40000 -53.0 -63.4  220  68 35   3.2   1.8 | -54.2 -65.6  225  64 33   4.2   2.3
 38000 -51.0 -59.8  225  54 28   3.4   1.8 | -51.6 -60.9  225  49 25   4.4   2.4
 36000 -49.0 -56.2  230  41 21   3.4   1.9 | -49.0 -56.2  225  34 18   4.5   2.4
 34000 -44.7 -48.5  235  32 16   8.9   4.9 | -44.3 -47.7  230  27 14   9.2   5.0
 32000 -38.6 -37.5  240  23 12   8.8   4.8 | -38.1 -36.6  245  22 11   9.1   5.0
 30000 -33.3 -27.9  240  19 10   8.8   4.8 | -33.0 -27.4  255  19 10   8.3   4.6
 29000 -30.7 -23.3  235  17  9   8.9   4.9 | -30.5 -22.9  260  17  9   8.3   4.6
 28000 -28.1 -18.6  235  15  8   8.5   4.6 | -28.1 -18.6  265  15  8   8.0   4.4
 27000 -25.8 -14.4  235  15  8   7.4   4.1 | -25.9 -14.6  275  15  8   7.1   3.9
 26000 -23.6 -10.5  230  15  8   7.4   4.1 | -23.8 -10.8  285  15  8   7.2   3.9
 25000 -21.5  -6.7  230  15  8   7.5   4.1 | -21.7  -7.1  295  16  8   7.2   4.0
 24000 -19.4  -2.9  230  16  8   6.9   3.8 | -19.6  -3.3  300  16  8   6.8   3.7
 23000 -17.4   0.7  230  16  8   6.9   3.8 | -17.6   0.3  305  17  9   6.8   3.8
 22000 -15.3   4.5  230  16  8   7.0   3.9 | -15.6   3.9  305  18  9   6.9   3.8
 21000 -13.5   7.7  225  16  8   6.1   3.4 | -13.7   7.3  310  19 10   6.3   3.5
 20000 -11.7  10.9  225  16  8   6.2   3.4 | -11.8  10.8  315  19 10   6.3   3.5
 19500 -10.8  12.6  220  16  8   6.2   3.4 | -10.9  12.4  315  19 10   6.3   3.5
 19000  -9.9  14.2  220  16  8   5.6   3.1 | -10.0  14.0  320  19 10   6.3   3.5
 18500  -9.1  15.6  215  16  8   5.3   2.9 |  -9.1  15.6  320  19 10   6.3   3.4
 18000  -8.4  16.9  210  16  8   5.3   2.9 |  -8.1  17.4  320  18  9   6.3   3.4
 17500  -7.7  18.1  200  16  8   4.1   2.2 |  -7.3  18.9  325  17  9   5.5   3.0
 17000  -7.1  19.2  195  16  8   4.3   2.4 |  -6.4  20.5  325  16  8   5.6   3.1
 16500  -6.6  20.1  185  16  8   1.3   0.7 |  -5.5  22.1  325  14  7   6.3   3.5
 16000  -6.5  20.3  175  15  8   0.5   0.3 |  -4.6  23.7  325  12  6   6.6   3.6
 15500  -6.1  21.0  160  14  7   5.8   3.2 |  -3.1  26.4  325   9  4   7.0   3.8
 15000  -5.2  22.6  155  13  7   6.0   3.3 |  -2.1  28.2  310   6  3   7.0   3.9
 14500  -4.3  24.3  150  13  6   7.4   4.0 |  -1.2  29.8  285   4  2   6.1   3.3
 14000  -3.1  26.4  140  12  6   8.0   4.4 |  -0.4  31.3  230   3  2   5.7   3.1
 13500  -2.0  28.4  135  11  5   8.4   4.6 |   0.4  32.7  190   5  3   5.6   3.0
 13000  -0.7  30.7  135  10  5   8.8   4.8 |   1.2  34.2  175   7  3   5.5   3.0
 12500   0.5  32.9  130   9  4   9.0   5.0 |   2.0  35.6  160   9  4   5.3   2.9
 12000   2.0  35.6  130   8  4   9.9   5.4 |   2.7  36.9  155  10  5   5.6   3.1
 11750   2.7  36.9  130   7  4   9.7   5.3 |   3.1  37.6  155  11  6   5.3   2.9
 11500   3.4  38.1  125   7  4  10.2   5.6 |   3.5  38.3  150  12  6   6.2   3.4
 11250   4.2  39.6  125   6  3  10.5   5.7 |   4.0  39.2  150  12  6   7.1   3.9
 11000   5.0  41.0  120   6  3   9.7   5.3 |   4.5  40.1  150  12  6   5.7   3.1
 10750   5.7  42.3  115   5  3   9.3   5.1 |   4.9  40.8  150  13  7   4.6   2.5
 10500   6.4  43.5  110   5  2   9.5   5.2 |   5.2  41.4  150  13  7   5.8   3.2
 10250   7.1  44.8  100   4  2   9.8   5.4 |   5.7  42.3  150  13  7   7.4   4.0
 10000   7.8  46.0  085   3  2   9.4   5.2 |   6.3  43.3  150  13  7   7.4   4.1
  9750   8.4  47.1  065   3  2   8.8   4.8 |   6.8  44.2  155  13  7   6.9   3.8
  9500   9.1  48.4  045   3  2   9.2   5.0 |   7.3  45.1  155  13  7   7.5   4.1
  9250   9.8  49.6  025   3  2   9.6   5.3 |   7.9  46.2  160  13  6   8.3   4.6
  9000  10.5  50.9  010   4  2   9.5   5.2 |   8.5  47.3  165  12  6   8.2   4.5
  8750  11.1  52.0  360   5  3   9.1   5.0 |   9.1  48.4  170  12  6  10.2   5.6
  8500  11.8  53.2  355   6  3   9.9   5.4 |  10.0  50.0  170  12  6  10.6   5.8
  8250  12.6  54.7  350   7  3  10.9   6.0 |  10.7  51.3  170  12  6   9.6   5.3
  8000  13.4  56.1  350   7  4  10.7   5.9 |  11.4  52.5  170  12  6   9.8   5.4
  7750  14.2  57.6  350   7  4  10.4   5.7 |  12.1  53.8  175  12  6  10.1   5.5
  7500  14.9  58.8  350   8  4  10.2   5.6 |  12.9  55.2  175  11  6   8.4   4.6
  7250  15.7  60.3  350   8  4  10.4   5.7 |  13.4  56.1  175  11  6   6.3   3.5
  7000  16.4  61.5  350   7  4  10.2   5.6 |  13.9  57.0  175  10  5   8.0   4.4
  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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