Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 221004
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Soaring Forecast
National Weather Service Pueblo, Colorado
0404 MDT Friday, April 22, 2016

This forecast is for Friday, April 22, 2016:

If the trigger temperature of 58.8 F/14.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1219 ft/min (6.2 m/s)
   Maximum height of thermals.................. 19465 ft MSL (12707 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13887 ft MSL (7129 ft AGL)
Thermal soaring outlook for Saturday 04/23..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:11:58 / 19:42:35 MDT
Total possible sunshine........... 13 hr 30 min 37 sec (810 min 37 sec)
Altitude of sun at 12:57:26 MDT... 63.58 degrees

Upper air data from numerical model forecast valid on 04/22/2016 at 0600 MDT

Freezing level.................. 12582 ft MSL (5824 ft AGL)
Convective condensation level... 15369 ft MSL (8611 ft AGL)
Lifted condensation level....... 16011 ft MSL (9253 ft AGL)
Lifted index.................... -1.8
K index......................... +3.7

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  -64.7 -84.5   290   17    9  -1.6  -0.9      M     M       M      M    M
 45000  -66.8 -88.2   305   21   11   3.4   1.8      M     M       M      M    M
 40000  -62.6 -80.7   330   22   11   2.9   1.6      M     M       M      M    M
 38000  -58.8 -73.8   330   24   12   7.6   4.2      M     M       M      M    M
 36000  -54.2 -65.6   330   26   13   7.6   4.2      M     M       M      M    M
 34000  -49.6 -57.3   330   27   14   8.0   4.4      M     M       M      M    M
 32000  -44.1 -47.4   330   26   13   8.0   4.4      M     M       M      M    M
 30000  -39.4 -38.9   325   23   12   7.7   4.2   30.4  86.7     8.0      M    M
 29000  -37.1 -34.8   325   21   11   7.7   4.2   29.6  85.2     7.5      M    M
 28000  -34.8 -30.6   320   20   10   7.6   4.2   28.9  83.9     7.0      M    M
 27000  -32.6 -26.7   320   18    9   7.0   3.9   28.0  82.4     6.4      M    M
 26000  -30.5 -22.9   315   17    9   7.1   3.9   26.9  80.4     5.6      M    M
 25000  -28.4 -19.1   310   16    8   7.1   3.9   26.0  78.7     4.9      M    M
 24000  -26.3 -15.3   305   16    8   6.9   3.8   25.0  77.0     4.2      M    M
 23000  -24.2 -11.6   305   15    8   6.9   3.8   23.9  75.0     3.3      M    M
 22000  -22.1  -7.8   300   15    8   6.9   3.8   22.9  73.3     2.5      M    M
 21000  -20.1  -4.2   290   14    7   6.4   3.5   21.9  71.4     1.6      M    M
 20000  -18.2  -0.8   285   15    8   6.5   3.5   20.7  69.3     0.6      M    M
 19500  -17.2   1.0   285   15    8   6.5   3.5   20.2  68.3     0.1      M    M
 19000  -16.2   2.8   280   15    8   6.5   3.5   19.6  67.4    -0.4   1185  6.0
 18500  -15.2   4.6   280   15    8   7.6   4.2   19.2  66.6    -0.8   1138  5.8
 18000  -14.1   6.6   275   14    7   7.5   4.1   18.8  65.9    -1.1   1090  5.5
 17500  -12.9   8.8   275   14    7   8.2   4.5   18.5  65.2    -1.4   1041  5.3
 17000  -11.6  11.1   275   13    7   8.4   4.6   18.2  64.8    -1.6    988  5.0
 16500  -10.4  13.3   275   12    6   8.5   4.7   18.0  64.5    -1.8    935  4.7
 16000   -8.4  16.9   280   11    6   8.9   4.9   17.8  64.0    -2.1    853  4.3
 15500   -7.1  19.2   280   11    6   8.6   4.7   17.7  63.8    -2.2    799  4.1
 15000   -5.8  21.6   280   12    6   8.4   4.6   17.4  63.4    -2.5    747  3.8
 14500   -4.6  23.7   280   13    7   8.5   4.7   17.2  63.0    -2.7    696  3.5
 14000   -3.4  25.9   280   14    7   8.9   4.9   17.0  62.7    -3.0    644  3.3
 13500   -2.1  28.2   275   15    8   9.1   5.0   16.9  62.4    -3.2    592  3.0
 13000   -0.9  30.4   270   16    8   8.9   4.9   16.8  62.2    -3.4    539  2.7
 12500    0.4  32.7   265   16    8   8.9   4.9   16.7  62.0    -3.7    486  2.5
 12000    1.6  34.9   260   17    9   8.2   4.5   16.5  61.6    -4.0    435  2.2
 11750    2.2  36.0   255   17    9   8.1   4.4   16.3  61.4    -4.1    410  2.1
 11500    2.8  37.0   250   17    9   8.6   4.7   16.2  61.2    -4.2    384  2.0
 11250    3.4  38.1   250   17    9   6.2   3.4   16.1  61.0    -4.4    359  1.8
 11000    3.8  38.8   245   18    9   5.5   3.0   15.7  60.3    -4.7    340  1.7
 10750    4.3  39.7   245   18    9   7.3   4.0   15.5  59.9    -5.0    317  1.6
 10500    4.8  40.6   240   18    9   7.1   3.9   15.3  59.5    -5.2    295  1.5
 10250    5.3  41.5   235   18    9   5.3   2.9   15.1  59.1    -5.4    272  1.4
 10000    5.6  42.1   235   18   10   4.1   2.3   14.6  58.3    -5.9    256  1.3
  9750    6.0  42.8   230   19   10   5.4   3.0   14.2  57.6    -6.3    238  1.2
  9500    6.3  43.3   225   19   10   5.3   2.9   13.9  57.0    -6.6    219  1.1
  9250    6.7  44.1   225   19   10   3.8   2.1   13.5  56.3    -7.0    201  1.0
  9000    6.9  44.4   220   19   10   2.6   1.4   13.0  55.4    -7.6    187  1.0
  8750    7.1  44.8   215   19   10   4.8   2.6   12.5  54.5    -8.1    173  0.9
  8500    7.5  45.5   215   19   10   4.6   2.5   12.2  53.9    -8.4    153  0.8
  8250    7.7  45.9   210   18    9   1.1   0.6   11.6  53.0    -9.0    140  0.7
  8000    7.8  46.0   210   17    9   0.2   0.1   10.9  51.7    -9.7    132  0.7
  7750    7.8  46.0   210   15    8   0.6   0.3   10.2  50.4   -10.4    124  0.6
  7500    7.5  45.5   210   15    8 -10.3  -5.7    9.3  48.7   -11.4    124  0.6
  7250    6.2  43.2   215   12    6 -20.7 -11.3    7.6  45.7   -13.1    156  0.8
  7000    4.9  40.8   220    9    5 -13.9  -7.6    5.9  42.7   -14.8    190  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/22/2016 at 0900 MDT          |       04/22/2016 at 1200 MDT
                                           |
K index... +19.1  LI... +272.6             | K index... +17.5  LI... +270.4
CAPE... +16.9  CIN... -5.9                 | CAPE... +173.0  CIN... -35.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.0 -85.0  275  20 10  -1.6  -0.9 | -65.2 -85.4  265  19 10  -1.5  -0.8
 45000 -67.1 -88.8  290  22 11   3.3   1.8 | -67.0 -88.6  275  22 11   3.7   2.0
 40000 -62.2 -80.0  310  17  9   2.9   1.6 | -62.1 -79.8  280  20 10   2.8   1.5
 38000 -58.3 -72.9  315  19 10   7.4   4.0 | -58.0 -72.4  285  20 10   7.5   4.1
 36000 -53.9 -65.0  320  22 11   7.4   4.0 | -53.6 -64.5  295  19 10   7.5   4.1
 34000 -49.3 -56.7  325  23 12   8.0   4.4 | -49.0 -56.2  300  19 10   7.9   4.3
 32000 -44.5 -48.1  325  23 12   8.0   4.4 | -44.3 -47.7  305  17  9   7.9   4.3
 30000 -39.7 -39.5  325  21 11   7.9   4.3 | -39.4 -38.9  310  16  8   8.3   4.5
 29000 -37.4 -35.3  325  20 10   7.9   4.3 | -36.9 -34.4  315  16  8   8.3   4.5
 28000 -35.0 -31.0  325  19 10   7.9   4.3 | -33.8 -28.8  315  16  8   8.3   4.6
 27000 -32.2 -26.0  320  18  9   7.0   3.8 | -31.5 -24.7  315  15  8   7.6   4.2
 26000 -30.1 -22.2  315  16  8   7.0   3.8 | -29.2 -20.6  310  15  8   7.6   4.2
 25000 -28.0 -18.4  310  15  8   7.0   3.8 | -27.0 -16.6  305  14  7   7.5   4.1
 24000 -25.9 -14.6  305  14  7   6.7   3.7 | -24.9 -12.8  300  14  7   5.9   3.2
 23000 -24.0 -11.2  305  14  7   6.7   3.7 | -23.2  -9.8  295  14  7   5.9   3.3
 22000 -22.0  -7.6  300  13  7   6.7   3.7 | -21.4  -6.5  290  14  7   6.0   3.3
 21000 -20.0  -4.0  300  13  7   6.4   3.5 | -19.6  -3.3  290  14  7   6.4   3.5
 20000 -18.2  -0.8  295  15  8   6.5   3.6 | -17.7   0.1  295  15  8   6.5   3.6
 19500 -17.2   1.0  295  16  8   6.6   3.6 | -16.8   1.8  295  15  8   6.5   3.6
 19000 -16.3   2.7  295  17  9   7.0   3.8 | -15.8   3.6  295  16  8   7.2   3.9
 18500 -15.2   4.6  295  17  9   7.9   4.3 | -14.6   5.7  295  16  8   8.6   4.7
 18000 -14.0   6.8  290  18  9   7.8   4.3 | -13.3   8.1  300  17  9   8.5   4.7
 17500 -12.8   9.0  290  18  9   8.7   4.8 | -12.1  10.2  300  17  9   8.7   4.8
 17000 -11.5  11.3  290  18  9   8.8   4.8 | -10.8  12.6  300  17  9   8.7   4.8
 16500 -10.2  13.6  295  17  9   8.9   4.9 |  -9.5  14.9  300  17  9   8.8   4.8
 16000  -8.9  16.0  295  16  8   8.9   4.9 |  -8.2  17.2  305  17  9   8.8   4.9
 15500  -7.6  18.3  295  15  8   9.0   4.9 |  -6.9  19.6  305  16  8   8.9   4.9
 15000  -6.2  20.8  295  14  7   9.4   5.2 |  -5.6  21.9  305  16  8   9.0   4.9
 14500  -4.8  23.4  300  14  7   9.4   5.1 |  -4.3  24.3  300  16  8   9.0   4.9
 14000  -3.4  25.9  300  14  7   9.5   5.2 |  -2.3  27.9  300  15  8   9.1   5.0
 13500  -1.3  29.7  295  14  7   9.6   5.2 |  -0.9  30.4  295  15  8   9.3   5.1
 13000   0.1  32.2  290  14  7   9.7   5.3 |   0.5  32.9  295  14  7   9.7   5.3
 12500   1.5  34.7  290  14  7   9.7   5.3 |   2.0  35.6  295  14  7   8.7   4.8
 12000   2.9  37.2  285  14  7   8.8   4.8 |   3.3  37.9  290  14  7   9.9   5.4
 11750   3.5  38.3  280  14  7   9.0   4.9 |   4.0  39.2  290  13  7   9.5   5.2
 11500   4.2  39.6  280  15  8   8.7   4.8 |   4.7  40.5  290  13  7   9.8   5.4
 11250   4.8  40.6  275  15  8   6.9   3.8 |   5.5  41.9  290  13  7   9.8   5.4
 11000   5.3  41.5  270  15  8   6.8   3.7 |   6.2  43.2  290  13  7   9.2   5.1
 10750   5.8  42.4  265  16  8   7.8   4.3 |   6.8  44.2  290  13  6   9.0   4.9
 10500   6.4  43.5  260  16  8   7.5   4.1 |   7.5  45.5  290  13  6   8.9   4.9
 10250   6.9  44.4  260  16  8   5.0   2.8 |   8.1  46.6  285  12  6   5.6   3.1
 10000   7.2  45.0  255  16  8   4.5   2.5 |   8.4  47.1  280  13  6   5.9   3.3
  9750   7.6  45.7  250  16  8   6.4   3.5 |   9.0  48.2  270  12  6   9.0   4.9
  9500   8.0  46.4  245  16  8   5.8   3.2 |   9.5  49.1  260  12  6   7.7   4.2
  9250   8.4  47.1  240  16  8   3.9   2.1 |  10.0  50.0  250  11  6   4.6   2.5
  9000   8.6  47.5  235  15  8   2.9   1.6 |  10.2  50.4  240  11  5   3.8   2.1
  8750   8.8  47.8  235  15  8   3.6   2.0 |  10.5  50.9  225  10  5   8.8   4.8
  8500   9.1  48.4  225  14  7   3.1   1.7 |  11.3  52.3  215  10  5  11.1   6.1
  8250   9.2  48.6  225  14  7   2.2   1.2 |  12.1  53.8  210  10  5   9.9   5.4
  8000   9.4  48.9  220  13  7   1.9   1.1 |  12.8  55.0  210  10  5   9.7   5.3
  7750   9.5  49.1  215  12  6   2.4   1.3 |  13.6  56.5  210  10  5  10.8   5.9
  7500   9.6  49.3  210  11  6   3.1   1.7 |  14.4  57.9  205  10  5  11.4   6.3
  7250   9.8  49.6  205  10  5   3.4   1.8 |  15.2  59.4  205   9  5  10.5   5.7
  7000  10.0  50.0  205   9  4   3.3   1.8 |  15.9  60.6  205   9  5  11.3   6.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/22/2016 at 1500 MDT          |       04/22/2016 at 1800 MDT
                                           |
K index... +20.7  LI... +269.0             | K index... +23.5  LI... +270.2
CAPE... +506.5  CIN... -10.4               | CAPE... +374.3  CIN... -30.1
                                           |
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 -65.7 -86.3  265  22 12  -2.2  -1.2 | -65.5 -85.9  270  20 10  -2.5  -1.4
 45000 -68.5 -91.3  260  23 12   4.7   2.6 | -68.8 -91.8  245  22 12   4.3   2.4
 40000 -61.9 -79.4  265  20 10   4.0   2.2 | -62.3 -80.1  250  27 14   3.9   2.1
 38000 -58.1 -72.6  275  20 10   6.8   3.7 | -58.4 -73.1  255  26 14   7.0   3.9
 36000 -54.0 -65.2  280  20 10   6.8   3.7 | -54.2 -65.6  260  26 13   7.0   3.9
 34000 -49.5 -57.1  285  20 10   8.3   4.5 | -49.5 -57.1  265  25 13   8.5   4.6
 32000 -44.5 -48.1  285  18  9   8.3   4.5 | -44.5 -48.1  265  22 11   8.5   4.6
 30000 -39.5 -39.1  285  17  9   8.4   4.6 | -39.5 -39.1  265  20 10   7.9   4.3
 29000 -37.0 -34.6  285  16  8   8.4   4.6 | -37.2 -35.0  265  19 10   7.9   4.4
 28000 -33.9 -29.0  290  14  7   8.4   4.6 | -34.2 -29.6  260  18  9   7.9   4.3
 27000 -31.4 -24.5  290  14  7   8.2   4.5 | -31.7 -25.1  260  18  9   8.5   4.6
 26000 -29.0 -20.2  290  14  7   8.2   4.5 | -29.2 -20.6  265  18  9   8.5   4.7
 25000 -26.5 -15.7  295  15  8   8.1   4.5 | -26.7 -16.1  270  18  9   8.5   4.6
 24000 -24.5 -12.1  295  15  8   5.0   2.7 | -24.3 -11.7  270  18  9   7.4   4.1
 23000 -23.0  -9.4  290  16  8   5.0   2.7 | -22.1  -7.8  275  18 10   7.4   4.1
 22000 -21.6  -6.9  285  16  8   5.0   2.8 | -19.9  -3.8  275  19 10   7.4   4.1
 21000 -19.7  -3.5  280  17  9   7.4   4.0 | -17.9  -0.2  280  19 10   6.1   3.3
 20000 -17.5   0.5  280  17  9   7.5   4.1 | -16.1   3.0  280  20 10   6.1   3.3
 19500 -16.4   2.5  280  18  9   7.5   4.1 | -15.2   4.6  280  20 11   6.1   3.4
 19000 -15.3   4.5  275  18  9   7.9   4.4 | -14.3   6.3  280  21 11   7.0   3.8
 18500 -14.0   6.8  275  18  9   8.7   4.8 | -13.1   8.4  280  21 11   9.1   5.0
 18000 -12.7   9.1  275  19 10   8.7   4.8 | -11.7  10.9  275  22 11   9.2   5.0
 17500 -11.4  11.5  275  19 10   9.4   5.2 | -10.4  13.3  275  22 11   9.1   5.0
 17000 -10.0  14.0  275  20 10   9.4   5.2 |  -9.1  15.6  270  22 11   9.2   5.0
 16500  -8.6  16.5  275  20 10   9.3   5.1 |  -7.8  18.0  270  21 11   9.2   5.0
 16000  -7.2  19.0  275  19 10   9.2   5.1 |  -6.5  20.3  265  20 10   9.1   5.0
 15500  -5.9  21.4  275  19 10   9.2   5.1 |  -5.2  22.6  260  19 10   9.1   5.0
 15000  -4.6  23.7  270  18  9   9.0   5.0 |  -3.8  25.2  255  18  9   9.3   5.1
 14500  -3.3  26.1  265  17  9   9.1   5.0 |  -2.5  27.5  250  17  9   9.3   5.1
 14000  -1.3  29.7  260  15  8   9.1   5.0 |  -0.5  31.1  245  17  9   8.9   4.9
 13500  -0.0  32.0  255  14  7   9.2   5.0 |   0.8  33.4  240  17  9   9.0   4.9
 13000   1.3  34.3  250  13  7   9.4   5.2 |   2.2  36.0  235  18  9   9.4   5.1
 12500   2.7  36.9  240  13  7   8.8   4.8 |   3.5  38.3  235  18  9   8.1   4.4
 12000   4.0  39.2  240  12  6   9.4   5.2 |   4.7  40.5  230  18  9   9.2   5.0
 11750   4.7  40.5  235  12  6   9.3   5.1 |   5.4  41.7  225  19 10   8.8   4.8
 11500   5.4  41.7  230  12  6   9.3   5.1 |   6.0  42.8  225  19 10   8.8   4.9
 11250   6.1  43.0  230  12  6   9.0   5.0 |   6.7  44.1  220  19 10   7.8   4.3
 11000   6.7  44.1  225  12  6   9.0   4.9 |   7.2  45.0  215  19 10   8.1   4.5
 10750   7.4  45.3  220  12  6   9.1   5.0 |   7.9  46.2  215  19 10   8.9   4.9
 10500   8.0  46.4  215  12  6   9.1   5.0 |   8.5  47.3  210  20 10   9.2   5.1
 10250   8.7  47.7  210  13  6   7.3   4.0 |   9.1  48.4  210  20 10   6.6   3.6
 10000   9.1  48.4  205  13  7   8.3   4.5 |   9.5  49.1  205  20 10   7.1   3.9
  9750   9.9  49.8  200  13  7  10.5   5.8 |  10.2  50.4  205  20 10  10.0   5.5
  9500  10.6  51.1  195  14  7   9.9   5.4 |  10.9  51.6  200  20 10   9.3   5.1
  9250  11.3  52.3  195  14  7   9.4   5.1 |  11.6  52.9  195  20 10   8.9   4.9
  9000  12.0  53.6  195  14  7   9.2   5.1 |  12.2  54.0  195  19 10   8.6   4.7
  8750  12.8  55.0  195  14  7  10.6   5.8 |  12.9  55.2  195  19 10   9.8   5.4
  8500  13.6  56.5  190  14  7  11.1   6.1 |  13.6  56.5  190  19 10  10.2   5.6
  8250  14.4  57.9  190  14  7  10.2   5.6 |  14.4  57.9  190  19 10   9.6   5.3
  8000  15.1  59.2  190  14  7  10.4   5.7 |  15.1  59.2  190  18  9   9.4   5.2
  7750  15.9  60.6  190  13  7   9.3   5.1 |  15.8  60.4  185  18  9   9.4   5.1
  7500  16.5  61.7  190  13  7   9.8   5.4 |  16.4  61.5  185  17  9   7.8   4.3
  7250  17.3  63.1  185  13  7  11.9   6.5 |  16.9  62.4  185  16  8   5.8   3.2
  7000  18.1  64.6  185  12  6  10.8   5.9 |  17.2  63.0  185  14  7   5.6   3.1
  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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