Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251431
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0831 MDT Thursday, August 25, 2016

This forecast is for Thursday, August 25, 2016:

If the trigger temperature of 62.9 F/17.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 492 ft/min (2.5 m/s)
   Maximum height of thermals.................. 14543 ft MSL (7785 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1100 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................. 10573 ft MSL (3815 ft AGL)
Thermal soaring outlook for Friday 08/26....... Good

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

Remarks...

Sunrise/Sunset.................... 06:22:03 / 19:40:21 MDT
Total possible sunshine........... 13 hr 18 min 18 sec (798 min 18 sec)
Altitude of sun at 13:00:48 MDT... 61.45 degrees

Upper air data from numerical model forecast valid on 08/25/2016 at 0600 MDT

Freezing level.................. 13618 ft MSL (6860 ft AGL)
Convective condensation level... 13412 ft MSL (6654 ft AGL)
Lifted condensation level....... 13389 ft MSL (6631 ft AGL)
Lifted index.................... -2.2
K index......................... +26.8

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  -59.4 -74.9   235   35   18   1.1   0.6      M     M       M      M    M
 45000  -57.6 -71.7   230   49   25   1.8   1.0      M     M       M      M    M
 40000  -55.0 -67.0   225   46   24   3.2   1.8      M     M       M      M    M
 38000  -52.1 -61.8   230   43   22   4.7   2.6      M     M       M      M    M
 36000  -49.3 -56.7   240   40   20   4.7   2.6      M     M       M      M    M
 34000  -44.7 -48.5   245   36   19   8.0   4.4      M     M       M      M    M
 32000  -39.8 -39.6   245   32   17   8.0   4.4      M     M       M      M    M
 30000  -34.9 -30.8   245   29   15   8.2   4.5   35.0  95.1    11.6      M    M
 29000  -32.5 -26.5   245   28   14   8.2   4.5   34.5  94.0    11.3      M    M
 28000  -30.0 -22.0   240   26   13   8.3   4.6   34.0  93.2    11.1      M    M
 27000  -27.9 -18.2   245   25   13   6.7   3.6   32.9  91.2    10.3      M    M
 26000  -25.9 -14.6   245   24   12   6.7   3.7   31.7  89.1     9.5      M    M
 25000  -23.9 -11.0   250   22   12   6.7   3.7   30.7  87.2     8.7      M    M
 24000  -21.9  -7.4   255   20   11   7.2   4.0   29.7  85.4     7.9      M    M
 23000  -19.7  -3.5   255   18    9   7.3   4.0   28.7  83.7     7.2      M    M
 22000  -17.6   0.3   260   16    8   7.4   4.1   27.9  82.2     6.5      M    M
 21000  -15.7   3.7   265   13    7   6.2   3.4   26.8  80.2     5.6      M    M
 20000  -13.8   7.2   265   11    5   6.2   3.4   25.5  77.9     4.5      M    M
 19500  -12.9   8.8   265    9    5   6.2   3.4   25.0  76.9     4.0      M    M
 19000  -12.0  10.4   265    8    4   6.4   3.5   24.4  75.9     3.5      M    M
 18500  -11.0  12.2   265    7    4   6.6   3.6   23.9  74.9     3.0      M    M
 18000  -10.1  13.8   265    6    3   6.6   3.6   23.3  74.0     2.6      M    M
 17500   -9.0  15.8   270    6    3   7.5   4.1   22.9  73.2     2.1      M    M
 17000   -7.9  17.8   275    5    3   7.4   4.1   22.5  72.5     1.8      M    M
 16500   -6.8  19.8   280    5    3   7.7   4.2   22.1  71.8     1.4      M    M
 16000   -5.1  22.8   275    6    3   7.9   4.3   21.6  70.9     0.9      M    M
 15500   -4.0  24.8   275    6    3   7.6   4.2   21.3  70.4     0.6      M    M
 15000   -2.9  26.8   280    7    3   7.6   4.2   21.0  69.7     0.2      M    M
 14500   -1.8  28.8   280    8    4   7.8   4.3   20.6  69.1    -0.1    678  3.4
 14000   -0.7  30.7   280    8    4   7.9   4.3   20.3  68.5    -0.5    630  3.2
 13500    0.5  32.9   280    8    4   8.6   4.7   20.0  68.0    -0.8    581  3.0
 13000    1.8  35.2   280    7    3   9.7   5.3   20.0  67.9    -0.9    526  2.7
 12500    3.2  37.8   270    5    3   9.6   5.3   20.0  68.0    -1.0    469  2.4
 12000    4.3  39.7   265    4    2   6.3   3.4   19.6  67.4    -1.3    421  2.1
 11750    4.8  40.6   260    3    2   6.7   3.7   19.4  66.9    -1.6    399  2.0
 11500    5.3  41.5   255    3    2   6.3   3.5   19.2  66.5    -1.8    377  1.9
 11250    5.7  42.3   245    3    1   5.7   3.1   18.9  66.0    -2.1    357  1.8
 11000    6.1  43.0   240    2    1   5.5   3.0   18.5  65.4    -2.5    338  1.7
 10750    6.5  43.7   235    2    1   5.8   3.2   18.2  64.8    -2.8    318  1.6
 10500    6.9  44.4   230    2    1   5.3   2.9   17.9  64.2    -3.2    299  1.5
 10250    7.2  45.0   225    2    1   4.0   2.2   17.5  63.5    -3.6    282  1.4
 10000    7.5  45.5   230    2    1   4.1   2.3   17.0  62.7    -4.1    267  1.4
  9750    7.8  46.0   235    3    1   5.3   2.9   16.7  62.0    -4.5    249  1.3
  9500    8.2  46.8   245    3    2   4.8   2.6   16.3  61.4    -4.8    230  1.2
  9250    8.5  47.3   245    4    2   3.5   1.9   15.9  60.6    -5.3    214  1.1
  9000    8.8  47.8   250    4    2   3.4   1.9   15.4  59.7    -5.7    199  1.0
  8750    9.0  48.2   255    5    3   0.7   0.4   14.9  58.7    -6.3    186  0.9
  8500    8.9  48.0   260    5    3  -2.1  -1.1   14.0  57.2    -7.1    180  0.9
  8250    8.8  47.8   255    6    3  -2.4  -1.3   13.1  55.6    -8.0    177  0.9
  8000    8.6  47.5   255    6    3  -1.4  -0.8   12.2  54.0    -8.9    173  0.9
  7750    8.5  47.3   255    6    3  -5.3  -2.9   11.3  52.3    -9.7    170  0.9
  7500    7.9  46.2   245    6    3  -7.2  -4.0   10.1  50.2   -11.0    181  0.9
  7250    7.5  45.5   240    5    3  -3.9  -2.1    9.4  48.8   -11.7    184  0.9
  7000    7.2  45.0   235    4    2  -6.7  -3.7    8.6  47.5   -12.4    187  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/25/2016 at 0900 MDT          |       08/25/2016 at 1200 MDT
                                           |
K index... +26.9  LI... +271.1             | K index... +19.4  LI... +270.1
CAPE... +156.9  CIN... -23.0               | CAPE... +301.3  CIN... -46.9
                                           |
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 -59.1 -74.4  235  34 18   1.5   0.8 | -58.9 -74.0  230  33 17   1.6   0.9
 45000 -56.8 -70.2  235  48 25   1.6   0.9 | -56.6 -69.9  235  46 23   1.4   0.8
 40000 -54.2 -65.6  225  52 27   3.9   2.1 | -54.3 -65.7  225  52 27   3.9   2.2
 38000 -51.8 -61.2  225  48 25   4.1   2.2 | -51.8 -61.2  225  52 27   4.1   2.3
 36000 -49.3 -56.7  230  45 23   4.1   2.2 | -49.3 -56.7  225  52 27   4.2   2.3
 34000 -45.3 -49.5  235  41 21   8.0   4.4 | -45.5 -49.9  230  49 25   7.5   4.1
 32000 -40.5 -40.9  240  37 19   8.0   4.4 | -41.0 -41.8  230  45 23   7.5   4.1
 30000 -35.7 -32.3  240  34 18   8.2   4.5 | -36.1 -33.0  235  40 21   8.5   4.7
 29000 -33.2 -27.8  240  33 17   8.2   4.5 | -33.5 -28.3  240  38 20   8.5   4.7
 28000 -30.1 -22.2  240  32 16   7.9   4.3 | -31.0 -23.8  240  36 19   8.6   4.7
 27000 -28.0 -18.4  245  30 16   7.1   3.9 | -28.1 -18.6  245  34 17   7.3   4.0
 26000 -25.8 -14.4  245  29 15   7.2   3.9 | -25.9 -14.6  245  32 16   7.3   4.0
 25000 -23.7 -10.7  250  27 14   7.3   4.0 | -23.8 -10.8  245  30 16   7.4   4.1
 24000 -21.7  -7.1  250  24 12   6.5   3.6 | -21.7  -7.1  245  28 14   6.6   3.6
 23000 -19.8  -3.6  250  21 11   6.6   3.6 | -19.8  -3.6  250  25 13   6.6   3.6
 22000 -17.9  -0.2  255  17  9   6.7   3.7 | -17.8  -0.0  250  22 11   6.6   3.6
 21000 -16.0   3.2  255  15  8   6.8   3.7 | -16.0   3.2  255  19 10   6.0   3.3
 20000 -14.0   6.8  260  14  7   6.8   3.7 | -14.2   6.4  265  16  8   6.1   3.3
 19500 -13.0   8.6  265  14  7   6.8   3.7 | -13.4   7.9  270  14  7   6.1   3.3
 19000 -12.0  10.4  265  13  7   7.3   4.0 | -12.4   9.7  280  14  7   7.4   4.0
 18500 -10.9  12.4  270  13  7   7.4   4.1 | -11.3  11.7  285  13  7   7.6   4.2
 18000  -9.8  14.4  270  13  7   7.5   4.1 | -10.2  13.6  295  13  7   7.8   4.3
 17500  -8.7  16.3  275  12  6   7.8   4.3 |  -8.9  16.0  300  13  7   8.5   4.6
 17000  -7.5  18.5  275  12  6   7.8   4.3 |  -7.7  18.1  305  14  7   8.4   4.6
 16500  -6.4  20.5  280  12  6   7.6   4.1 |  -6.4  20.5  310  14  7   9.0   5.0
 16000  -5.3  22.5  285  11  6   7.5   4.1 |  -5.1  22.8  310  13  7   9.1   5.0
 15500  -4.2  24.4  285  11  6   7.4   4.1 |  -3.8  25.2  310  13  7   8.9   4.9
 15000  -3.1  26.4  290  11  5   7.3   4.0 |  -2.5  27.5  305  12  6   8.8   4.8
 14500  -2.1  28.2  290  10  5   7.4   4.1 |  -1.3  29.7  300  12  6   8.7   4.8
 14000  -0.3  31.5  295   9  5   8.2   4.5 |   0.5  32.9  295  10  5   8.2   4.5
 13500   0.8  33.4  295   9  4   8.6   4.7 |   1.6  34.9  290   9  5   7.9   4.4
 13000   2.1  35.8  285   7  4   8.9   4.9 |   2.7  36.9  285   8  4   7.8   4.3
 12500   3.4  38.1  280   5  3   8.6   4.7 |   3.8  38.8  275   7  4   7.4   4.1
 12000   4.5  40.1  255   5  2   6.7   3.7 |   4.8  40.6  270   7  4   7.5   4.1
 11750   4.9  40.8  245   5  2   7.4   4.0 |   5.3  41.5  270   7  3   7.7   4.2
 11500   5.4  41.7  235   5  3   5.5   3.0 |   5.8  42.4  265   6  3   6.6   3.6
 11250   5.7  42.3  225   5  3   3.5   1.9 |   6.2  43.2  260   6  3   4.2   2.3
 11000   6.0  42.8  220   6  3   4.5   2.4 |   6.4  43.5  255   5  3   2.9   1.6
 10750   6.3  43.3  215   6  3   5.0   2.8 |   6.6  43.9  245   4  2   2.5   1.4
 10500   6.6  43.9  210   6  3   4.4   2.4 |   6.7  44.1  230   4  2   2.6   1.5
 10250   6.9  44.4  205   6  3   3.4   1.9 |   6.9  44.4  205   4  2   1.8   1.0
 10000   7.1  44.8  205   6  3   4.1   2.2 |   7.0  44.6  185   4  2   4.0   2.2
  9750   7.5  45.5  200   6  3   5.1   2.8 |   7.4  45.3  170   5  3   6.4   3.5
  9500   7.9  46.2  195   6  3   4.8   2.6 |   7.9  46.2  160   7  4   7.4   4.1
  9250   8.2  46.8  190   6  3   4.5   2.5 |   8.5  47.3  160   7  4   8.6   4.7
  9000   8.5  47.3  190   6  3   4.6   2.5 |   9.1  48.4  160   8  4   8.5   4.7
  8750   8.9  48.0  185   6  3   5.5   3.0 |   9.8  49.6  160   8  4  10.4   5.7
  8500   9.4  48.9  180   6  3   6.7   3.7 |  10.6  51.1  160   8  4  10.9   6.0
  8250   9.9  49.8  180   5  3   7.2   4.0 |  11.4  52.5  160   8  4  10.4   5.7
  8000  10.4  50.7  180   4  2   6.2   3.4 |  12.2  54.0  160   8  4   9.9   5.4
  7750  10.9  51.6  180   4  2   9.6   5.3 |  13.0  55.4  160   8  4  12.2   6.7
  7500  11.7  53.1  175   4  2  10.9   6.0 |  14.0  57.2  155   9  4  14.1   7.7
  7250  12.4  54.3  170   4  2   7.9   4.3 |  14.9  58.8  155   8  4  12.7   7.0
  7000  13.0  55.4  165   3  2  10.5   5.7 |  15.9  60.6  155   8  4  14.0   7.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/25/2016 at 1500 MDT          |       08/25/2016 at 1800 MDT
                                           |
K index... +17.3  LI... +270.7             | K index... +26.5  LI... +271.0
CAPE... +267.8  CIN... -44.6               | CAPE... +207.5  CIN... -3.0
                                           |
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 -59.5 -75.1  225  38 19   1.2   0.7 | -59.2 -74.6  230  38 20   1.4   0.7
 45000 -57.5 -71.5  225  48 25   1.6   0.9 | -57.6 -71.7  230  48 25   0.0   0.0
 40000 -54.9 -66.8  230  53 27   4.8   2.7 | -57.2 -71.0  225  51 26   6.4   3.5
 38000 -52.0 -61.6  235  52 27   4.7   2.6 | -53.4 -64.1  235  42 22   6.4   3.5
 36000 -49.2 -56.6  235  51 26   4.8   2.6 | -49.5 -57.1  250  35 18   6.5   3.5
 34000 -45.0 -49.0  240  47 24   7.9   4.3 | -44.6 -48.3  255  34 18   8.9   4.9
 32000 -40.3 -40.5  245  43 22   7.9   4.4 | -39.2 -38.6  260  34 18   9.0   4.9
 30000 -35.3 -31.5  250  40 21   8.5   4.7 | -34.1 -29.4  255  34 18   8.4   4.6
 29000 -32.8 -27.0  250  39 20   8.5   4.7 | -31.7 -25.1  255  34 18   8.4   4.6
 28000 -30.3 -22.5  250  38 20   8.6   4.7 | -29.2 -20.6  255  34 18   8.5   4.7
 27000 -27.3 -17.1  250  36 18   7.9   4.3 | -26.3 -15.3  255  34 17   7.5   4.1
 26000 -24.9 -12.8  250  33 17   7.9   4.3 | -24.1 -11.4  255  33 17   7.5   4.1
 25000 -22.6  -8.7  255  31 16   8.0   4.4 | -21.9  -7.4  250  33 17   7.6   4.2
 24000 -20.5  -4.9  255  28 15   6.8   3.7 | -19.8  -3.6  250  32 16   6.7   3.7
 23000 -18.5  -1.3  255  26 13   6.8   3.7 | -17.9  -0.2  245  30 16   6.7   3.7
 22000 -16.4   2.5  255  23 12   6.9   3.8 | -15.9   3.4  245  29 15   6.9   3.8
 21000 -14.7   5.5  250  20 10   5.6   3.1 | -14.3   6.3  240  25 13   5.2   2.8
 20000 -13.0   8.6  250  17  9   5.6   3.1 | -12.8   9.0  230  22 11   5.2   2.9
 19500 -12.1  10.2  245  16  8   5.6   3.0 | -12.0  10.4  225  20 10   5.2   2.9
 19000 -11.3  11.7  245  15  8   6.4   3.5 | -11.3  11.7  220  19 10   4.7   2.6
 18500 -10.3  13.5  245  14  7   6.6   3.6 | -10.6  12.9  210  17  9   4.6   2.5
 18000  -9.3  15.3  240  13  7   6.8   3.7 |  -9.9  14.2  200  16  8   4.7   2.6
 17500  -8.3  17.1  240  11  5   7.8   4.3 |  -9.1  15.6  195  15  8   6.2   3.4
 17000  -7.1  19.2  240   8  4   7.7   4.2 |  -8.3  17.1  190  14  7   6.1   3.3
 16500  -6.0  21.2  245   6  3   8.1   4.4 |  -7.4  18.7  185  14  7   6.6   3.6
 16000  -4.8  23.4  245   4  2   8.2   4.5 |  -6.4  20.5  180  13  7   6.7   3.7
 15500  -3.6  25.5  250   3  1   8.4   4.6 |  -5.4  22.3  180  13  7   6.9   3.8
 15000  -2.4  27.7  240   2  1   8.6   4.7 |  -4.4  24.1  175  12  6   7.3   4.0
 14500  -1.2  29.8  220   2  1   8.6   4.7 |  -3.3  26.1  175  11  5   7.3   4.0
 14000   0.1  32.2  205   2  1   8.8   4.8 |  -2.3  27.9  165   9  5   7.0   3.8
 13500   2.0  35.6  195   3  1   8.1   4.4 |  -0.8  30.6  145   7  4   7.0   3.8
 13000   3.0  37.4  190   4  2   7.5   4.1 |   0.2  32.4  140   7  4   7.0   3.9
 12500   4.0  39.2  190   5  3   6.9   3.8 |   1.1  34.0  135   7  4   7.7   4.2
 12000   4.9  40.8  180   6  3   7.2   3.9 |   2.3  36.1  130   7  4   8.6   4.7
 11750   5.4  41.7  175   7  3   7.3   4.0 |   2.9  37.2  130   7  3   8.1   4.4
 11500   5.8  42.4  170   7  4   6.2   3.4 |   3.5  38.3  130   6  3  10.2   5.6
 11250   6.1  43.0  160   8  4   3.8   2.1 |   4.4  39.9  135   6  3  11.6   6.4
 11000   6.4  43.5  160   9  5   3.3   1.8 |   5.1  41.2  130   6  3   9.4   5.2
 10750   6.6  43.9  155  10  5   2.9   1.6 |   5.8  42.4  130   5  3   8.7   4.8
 10500   6.8  44.2  155  11  6   4.7   2.6 |   6.4  43.5  130   5  3   9.3   5.1
 10250   7.2  45.0  155  12  6   7.7   4.2 |   7.1  44.8  130   5  2  10.3   5.6
 10000   7.8  46.0  155  12  6   8.7   4.8 |   7.9  46.2  130   4  2   9.1   5.0
  9750   8.5  47.3  155  12  6   9.2   5.0 |   8.5  47.3  125   4  2   7.5   4.1
  9500   9.2  48.6  155  12  6   9.3   5.1 |   9.0  48.2  110   3  1   8.4   4.6
  9250   9.9  49.8  155  12  6   9.6   5.2 |   9.7  49.5  100   2  1   9.3   5.1
  9000  10.6  51.1  155  12  6   9.7   5.3 |  10.4  50.7  080   2  1   9.2   5.1
  8750  11.3  52.3  155  12  6  10.8   5.9 |  11.0  51.8  040   1  1   8.6   4.7
  8500  12.2  54.0  155  13  6  11.1   6.1 |  11.7  53.1  360   3  1   9.2   5.0
  8250  13.0  55.4  155  12  6  10.9   6.0 |  12.4  54.3  355   3  2  10.0   5.5
  8000  13.8  56.8  155  12  6  10.3   5.7 |  13.1  55.6  350   3  2   9.9   5.4
  7750  14.6  58.3  155  12  6  12.8   7.0 |  13.8  56.8  345   4  2   9.8   5.4
  7500  15.6  60.1  155  12  6  14.1   7.7 |  14.5  58.1  340   4  2   7.9   4.3
  7250  16.6  61.9  155  12  6  12.1   6.6 |  15.0  59.0  340   4  2   6.4   3.5
  7000  17.5  63.5  155  12  6  13.8   7.6 |  15.5  59.9  340   4  2   7.5   4.1
  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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