Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201314
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0714 MDT Friday, May 20, 2016

This forecast is for Friday, May 20, 2016:

If the trigger temperature of 71.1 F/21.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1023 ft/min (5.2 m/s)
   Maximum height of thermals.................. 16296 ft MSL (11011 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9690 ft MSL (4404 ft AGL)
Thermal soaring outlook for Saturday 05/21..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16097 ft MSL (10812 ft AGL)
Wave soaring outlook for Saturday 05/21........ Poor

Remarks...

Sunrise/Sunset.................... 05:40:21 / 20:11:35 MDT
Total possible sunshine........... 14 hr 31 min 14 sec (871 min 14 sec)
Altitude of sun at 12:56:10 MDT... 70.40 degrees

Upper air data from rawinsonde observation taken on 05/20/2016 at 0600 MDT

Freezing level.................. 12839 ft MSL (7554 ft AGL)
Convective condensation level... 16215 ft MSL (10930 ft AGL)
Lifted condensation level....... 16333 ft MSL (11048 ft AGL)
Lifted index.................... -0.2
K index......................... +11.8

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  -60.8 -77.4   270   21   11   3.1   1.7   97.3 207.1    41.4      M    M
 45000  -60.2 -76.4   255   32   17   4.0   2.2   73.8 164.8    30.0      M    M
 40000  -64.6 -84.3   295   28   14 -13.6  -7.5   42.6 108.7    11.7      M    M
 38000  -62.3 -80.1   280   40   21   9.2   5.0   37.4  99.3     8.4      M    M
 36000  -56.9 -70.4   270   34   17   9.5   5.2   36.8  98.2     8.2      M    M
 34000  -51.3 -60.3   260   28   15   9.6   5.3   36.2  97.2     8.0      M    M
 32000  -45.6 -50.1   260   21   11   9.6   5.3   36.1  96.9     8.1      M    M
 30000  -40.6 -41.1   260   11    6   7.3   4.0   35.1  95.2     7.6      M    M
 29000  -37.9 -36.2   270   11    6   9.3   5.1   34.8  94.6     7.5      M    M
 28000  -34.4 -29.9   280   13    7   9.3   5.1   34.6  94.3     7.4      M    M
 27000  -31.6 -24.9   285   15    8   9.3   5.1   34.4  94.0     7.4      M    M
 26000  -29.0 -20.2   290   17    9   6.4   3.5   34.0  93.2     7.1      M    M
 25000  -26.7 -16.1   285   16    8   8.7   4.8   33.3  92.0     6.7      M    M
 24000  -24.1 -11.4   280   17    9   6.9   3.8   32.9  91.3     6.4      M    M
 23000  -22.4  -8.3   275   22   11   7.1   3.9   31.5  88.6     5.3      M    M
 22000  -20.2  -4.4   270   20   10   6.6   3.6   30.5  87.0     4.6      M    M
 21000  -18.1  -0.6   270   18    9   9.3   5.1   29.6  85.3     3.9      M    M
 20000  -15.7   3.7   265   16    8   4.2   2.3   29.0  84.2     3.3      M    M
 19500  -15.0   5.0   275   13    7   4.6   2.5   28.1  82.6     2.6      M    M
 19000  -14.3   6.3   290   10    5   6.0   3.3   27.3  81.2     1.9      M    M
 18500  -13.1   8.4   300    9    5  10.3   5.6   27.0  80.6     1.6      M    M
 18000  -11.7  10.9   290   10    5   7.0   3.8   26.9  80.4     1.5      M    M
 17500  -10.8  12.6   285   10    5   6.3   3.5   26.3  79.3     1.0      M    M
 17000   -9.9  14.2   275   11    6   7.1   3.9   25.7  78.3     0.4      M    M
 16500   -8.7  16.3   270   13    6   8.0   4.4   25.4  77.7     0.1      M    M
 16000   -7.5  18.5   265   14    7   8.1   4.4   25.1  77.2    -0.1   1003  5.1
 15500   -6.3  20.7   265   14    7   8.1   4.5   24.8  76.7    -0.4    952  4.8
 15000   -5.2  22.6   265   14    7   7.4   4.1   24.5  76.1    -0.7    902  4.6
 14500   -4.1  24.6   265   13    7   7.4   4.1   24.1  75.4    -1.1    856  4.3
 14000   -2.5  27.5   265   13    7   7.5   4.1   23.6  74.4    -1.7    786  4.0
 13500   -1.4  29.5   270   13    7   7.7   4.2   23.2  73.8    -2.1    739  3.8
 13000   -0.2  31.6   270   12    6   9.4   5.2   23.0  73.4    -2.3    687  3.5
 12500    1.2  34.2   275   12    6   9.3   5.1   23.0  73.3    -2.4    631  3.2
 12000    2.6  36.7   275   12    6   9.3   5.1   22.9  73.2    -2.5    575  2.9
 11500    3.9  39.0   270   12    6   9.3   5.1   22.8  73.0    -2.6    519  2.6
 11000    5.3  41.5   265   12    6   9.3   5.1   22.7  72.9    -2.7    463  2.4
 10500    6.7  44.1   265   12    6   9.3   5.1   22.6  72.8    -2.8    407  2.1
 10250    7.4  45.3   260   12    6   9.2   5.1   22.6  72.7    -2.8    379  1.9
 10000    8.1  46.6   260   12    6   8.9   4.9   22.6  72.6    -2.9    351  1.8
  9750    8.7  47.7   265   12    6   8.7   4.8   22.5  72.5    -3.0    325  1.6
  9500    9.3  48.7   265   12    6   8.7   4.8   22.4  72.3    -3.1    298  1.5
  9250   10.0  50.0   270   12    6   8.7   4.8   22.3  72.2    -3.2    271  1.4
  9000   10.6  51.1   270   12    6   8.7   4.8   22.3  72.1    -3.2    244  1.2
  8750   11.3  52.3   270   12    6   8.7   4.8   22.2  71.9    -3.3    218  1.1
  8500   11.9  53.4   275   12    6   8.7   4.8   22.1  71.8    -3.4    191  1.0
  8250   12.6  54.7   275   12    6   8.7   4.8   22.0  71.7    -3.5    164  0.8
  8000   13.2  55.8   275   12    6   8.7   4.8   22.0  71.5    -3.6    137  0.7
  7750   13.9  57.0   280   12    6   8.7   4.8   21.9  71.4    -3.7    111  0.6
  7500   14.5  58.1   285   12    6   8.8   4.8   21.8  71.2    -3.8     84  0.4
  7250   15.1  59.2   290   12    6   8.3   4.6   21.7  71.1    -3.9     57  0.3
  7000   15.6  60.1   295   12    6   4.1   2.3   21.5  70.6    -4.1     35  0.2
  6750   15.8  60.4   290   10    5   1.7   1.0   20.9  69.6    -4.8     24  0.1
  6500   15.9  60.6   280    8    4   1.9   1.1   20.3  68.6    -5.4     13  0.1
  6250   16.0  60.8   265    6    3   3.7   2.0   19.7  67.5    -6.0      2  0.0
  6000   16.1  61.0   240    5    3  -3.4  -1.8   19.2  66.5    -6.6      M    M
  5750   15.3  59.5   220    5    3 -17.0  -9.3   17.6  63.7    -8.2      9  0.0
  5500   13.7  56.7   205    5    3 -21.6 -11.9   15.4  59.7   -10.5     48  0.2

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

           05/20/2016 at 0900 MDT          |       05/20/2016 at 1200 MDT
                                           |
K index... +22.6  LI... -0.3               | K index... +24.0  LI... -1.7
CAPE... +18.9  CIN... -77.3                | CAPE... +313.5  CIN... -16.1
                                           |
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 -61.1 -78.0  265  21 11  -0.6  -0.3 | -60.4 -76.7  270  22 11  -0.3  -0.1
 45000 -61.9 -79.4  265  34 18  -1.0  -0.5 | -60.9 -77.6  275  32 16  -2.1  -1.1
 40000 -63.9 -83.0  275  34 17  -1.0  -0.6 | -63.7 -82.7  270  35 18  -1.7  -0.9
 38000 -60.8 -77.4  270  34 17   7.8   4.3 | -60.8 -77.4  265  34 17   7.8   4.3
 36000 -56.1 -69.0  265  34 18   7.8   4.3 | -56.1 -69.0  260  32 17   7.7   4.3
 34000 -51.3 -60.3  265  31 16   8.5   4.7 | -51.1 -60.0  255  30 16   9.4   5.1
 32000 -46.2 -51.2  265  24 12   8.5   4.7 | -44.8 -48.6  250  26 14   9.3   5.1
 30000 -40.4 -40.7  265  19 10   8.8   4.8 | -39.4 -38.9  250  23 12   8.7   4.8
 29000 -37.8 -36.0  265  18  9   8.8   4.8 | -36.8 -34.2  250  21 11   8.7   4.8
 28000 -35.1 -31.2  260  18  9   8.8   4.8 | -34.2 -29.6  255  19 10   8.7   4.8
 27000 -32.5 -26.5  260  18  9   9.0   5.0 | -31.6 -24.9  255  18  9   8.0   4.4
 26000 -29.8 -21.6  260  18  9   9.1   5.0 | -29.3 -20.7  255  17  9   8.0   4.4
 25000 -27.1 -16.8  265  18  9   9.1   5.0 | -26.9 -16.4  255  17  8   8.0   4.4
 24000 -24.5 -12.1  265  17  9   7.5   4.1 | -24.5 -12.1  255  16  8   7.8   4.3
 23000 -22.3  -8.1  260  17  9   7.7   4.2 | -22.2  -8.0  250  17  9   7.8   4.3
 22000 -20.0  -4.0  255  16  8   7.7   4.2 | -19.9  -3.8  250  18  9   7.8   4.3
 21000 -17.8  -0.0  255  15  8   6.8   3.7 | -17.7   0.1  245  18  9   6.9   3.8
 20000 -15.8   3.6  255  12  6   6.8   3.7 | -15.6   3.9  245  17  9   7.0   3.8
 19500 -14.8   5.4  255  11  6   6.8   3.7 | -14.6   5.7  245  17  9   7.0   3.8
 19000 -13.8   7.2  255  10  5   6.8   3.8 | -13.6   7.5  245  16  8   7.0   3.8
 18500 -12.8   9.0  255   9  5   6.9   3.8 | -12.6   9.3  240  16  8   6.9   3.8
 18000 -11.8  10.8  255   9  5   6.9   3.8 | -11.6  11.1  235  15  7   6.9   3.8
 17500 -10.8  12.6  255   8  4   7.0   3.8 | -10.6  12.9  230  14  7   6.8   3.7
 17000  -9.7  14.5  250   9  4   7.1   3.9 |  -9.1  15.6  230  13  7   6.7   3.7
 16500  -8.7  16.3  250   9  5   7.1   3.9 |  -8.1  17.4  230  13  7   6.9   3.8
 16000  -7.6  18.3  250   9  5   7.8   4.3 |  -7.0  19.4  225  13  7   7.0   3.8
 15500  -5.9  21.4  245   9  5   7.7   4.2 |  -6.0  21.2  220  13  7   7.1   3.9
 15000  -4.7  23.5  240   9  5   7.6   4.2 |  -4.8  23.4  215  13  7   7.7   4.2
 14500  -3.6  25.5  235   9  5   7.5   4.1 |  -3.7  25.3  215  13  7   7.6   4.2
 14000  -2.4  27.7  225  10  5   8.5   4.7 |  -2.5  27.5  215  13  7   8.6   4.7
 13500  -1.2  29.8  220  10  5   8.4   4.6 |  -1.2  29.8  210  13  7   8.6   4.7
 13000   0.0  32.0  210  10  5   8.5   4.7 |  -0.0  32.0  210  12  6   8.1   4.4
 12500   1.3  34.3  210   9  5   8.5   4.7 |   1.1  34.0  210  11  6   8.0   4.4
 12000   2.5  36.5  205   9  5   8.7   4.8 |   2.3  36.1  210  10  5   8.7   4.8
 11500   3.8  38.8  210   8  4   8.8   4.8 |   3.6  38.5  215   9  5   8.8   4.8
 11000   5.0  41.0  220   7  3   7.9   4.3 |   4.9  40.8  225   8  4   7.8   4.3
 10500   6.2  43.2  240   5  3   6.9   3.8 |   6.0  42.8  240   7  4   6.8   3.7
 10250   6.7  44.1  250   5  3  11.0   6.0 |   6.5  43.7  250   7  3  10.9   6.0
 10000   7.7  45.9  275   6  3  11.7   6.4 |   7.5  45.5  260   6  3  10.7   5.9
  9750   8.3  46.9  280   7  4   8.0   4.4 |   8.0  46.4  265   6  3   6.6   3.6
  9500   9.0  48.2  290   8  4   9.3   5.1 |   8.5  47.3  270   5  3   7.4   4.1
  9250   9.6  49.3  295   9  5   7.9   4.4 |   9.0  48.2  280   5  2   8.5   4.7
  9000  10.2  50.4  295  11  6   7.1   3.9 |   9.7  49.5  280   5  2   9.9   5.4
  8750  10.7  51.3  295  12  6   7.5   4.1 |  10.4  50.7  280   4  2   9.5   5.2
  8500  11.2  52.2  295  13  7   7.5   4.1 |  11.1  52.0  280   4  2   9.5   5.2
  8250  11.8  53.2  295  14  7   7.4   4.0 |  11.8  53.2  280   4  2  10.0   5.5
  8000  12.3  54.1  295  13  7   7.3   4.0 |  12.6  54.7  280   4  2  10.2   5.6
  7750  12.9  55.2  295  13  7   7.5   4.1 |  13.3  55.9  280   4  2   9.5   5.2
  7500  13.5  56.3  295  12  6   7.5   4.1 |  14.0  57.2  280   4  2   9.5   5.2
  7250  14.0  57.2  295  11  6   7.1   3.9 |  14.8  58.6  280   4  2  10.6   5.8
  7000  14.5  58.1  295  10  5   6.5   3.6 |  15.6  60.1  280   4  2  11.1   6.1
  6750  15.0  59.0  295   9  5   6.2   3.4 |  16.4  61.5  285   4  2   9.7   5.3
  6500  15.4  59.7  295   8  4   4.8   2.6 |  17.1  62.8  285   4  2   9.7   5.3
  6250  15.7  60.3  290   7  3   2.5   1.4 |  17.8  64.0  285   4  2  10.9   6.0
  6000  15.8  60.4  280   5  3   1.8   1.0 |  18.6  65.5  285   4  2  11.0   6.1
  5750  15.9  60.6  260   4  2   2.0   1.1 |  19.4  66.9  285   4  2  10.4   5.7
  5500  16.0  60.8  220   3  2   7.5   4.1 |  20.3  68.5  285   4  2  16.3   9.0

           05/20/2016 at 1500 MDT          |       05/20/2016 at 1800 MDT
                                           |
K index... +26.0  LI... -1.5               | K index... +28.6  LI... -1.4
CAPE... +338.3  CIN... -16.7               | CAPE... +396.1  CIN... -8.8
                                           |
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 -60.7 -77.3  270  25 13  -0.0  -0.0 | -61.2 -78.2  275  23 12  -0.3  -0.2
 45000 -60.9 -77.6  280  35 18  -2.1  -1.2 | -61.8 -79.2  280  28 14  -1.1  -0.6
 40000 -63.8 -82.8  275  31 16  -1.7  -0.9 | -63.4 -82.1  265  25 13  -0.7  -0.4
 38000 -60.5 -76.9  270  28 15   8.3   4.6 | -59.8 -75.6  265  26 13   8.3   4.5
 36000 -55.5 -67.9  265  26 13   8.3   4.6 | -54.2 -65.6  260  27 14   8.3   4.5
 34000 -49.6 -57.3  265  25 13   9.2   5.0 | -49.0 -56.2  260  28 15   9.0   4.9
 32000 -44.1 -47.4  265  24 12   9.2   5.0 | -43.6 -46.5  270  30 16   9.0   4.9
 30000 -38.7 -37.7  265  23 12   8.8   4.8 | -38.2 -36.8  275  31 16   8.9   4.9
 29000 -36.1 -33.0  265  22 11   8.8   4.8 | -35.5 -31.9  275  30 16   8.9   4.9
 28000 -33.5 -28.3  260  21 11   8.7   4.8 | -32.9 -27.2  275  30 15   8.9   4.9
 27000 -31.0 -23.8  260  20 10   7.9   4.3 | -30.4 -22.7  280  28 15   8.1   4.5
 26000 -28.7 -19.7  260  19 10   7.8   4.3 | -27.9 -18.2  280  27 14   8.1   4.5
 25000 -26.3 -15.3  260  19 10   7.9   4.3 | -25.5 -13.9  285  25 13   8.1   4.5
 24000 -24.0 -11.2  260  18  9   7.6   4.2 | -23.1  -9.6  285  24 12   7.8   4.3
 23000 -21.7  -7.1  260  17  9   7.7   4.2 | -20.8  -5.4  280  22 11   7.8   4.3
 22000 -19.5  -3.1  260  17  9   7.7   4.2 | -18.5  -1.3  275  21 11   7.8   4.3
 21000 -17.2   1.0  255  18  9   7.4   4.1 | -16.3   2.7  265  20 10   7.3   4.0
 20000 -15.0   5.0  250  19 10   7.4   4.1 | -14.1   6.6  255  21 11   7.3   4.0
 19500 -13.9   7.0  245  21 11   7.4   4.1 | -13.1   8.4  250  22 11   7.3   4.0
 19000 -12.8   9.0  245  22 11   7.5   4.1 | -12.0  10.4  245  23 12   7.4   4.1
 18500 -11.8  10.8  245  22 11   6.9   3.8 | -10.5  13.1  240  23 12   6.9   3.8
 18000 -10.8  12.6  240  22 11   7.0   3.8 |  -9.5  14.9  235  24 12   7.0   3.8
 17500  -9.2  15.4  240  22 11   6.9   3.8 |  -8.5  16.7  230  23 12   6.3   3.4
 17000  -8.2  17.2  235  22 11   6.9   3.8 |  -7.6  18.3  225  23 12   6.3   3.5
 16500  -7.2  19.0  230  22 11   7.7   4.2 |  -6.6  20.1  220  23 12   6.0   3.3
 16000  -6.0  21.2  230  20 10   8.1   4.4 |  -5.8  21.6  215  21 11   5.9   3.2
 15500  -4.8  23.4  230  18  9   8.0   4.4 |  -4.9  23.2  210  19 10   6.0   3.3
 15000  -3.7  25.3  230  17  9   7.8   4.3 |  -4.0  24.8  200  17  9   6.5   3.6
 14500  -2.5  27.5  225  15  8   7.8   4.3 |  -3.0  26.6  190  16  8   6.4   3.5
 14000  -1.3  29.7  220  14  7   8.2   4.5 |  -1.9  28.6  175  15  8   8.4   4.6
 13500  -0.1  31.8  210  14  7   8.2   4.5 |  -0.8  30.6  165  14  7   8.1   4.5
 13000   1.0  33.8  200  13  7   7.3   4.0 |   0.5  32.9  160  13  7   9.4   5.2
 12500   2.0  35.6  185  12  6   7.3   4.0 |   1.9  35.4  155  13  6   9.4   5.2
 12000   3.1  37.6  175  11  5   8.0   4.4 |   3.3  37.9  150  12  6  10.0   5.5
 11500   4.3  39.7  170   9  5   8.1   4.5 |   4.8  40.6  150  12  6  10.1   5.6
 11000   5.4  41.7  160   8  4   8.2   4.5 |   6.2  43.2  150  12  6   8.6   4.7
 10500   6.7  44.1  160   7  4   7.6   4.2 |   7.5  45.5  150  11  6   7.5   4.1
 10250   7.3  45.1  155   7  4  11.1   6.1 |   8.1  46.6  150  11  6  11.7   6.4
 10000   8.2  46.8  155   7  4  12.0   6.6 |   9.2  48.6  150  11  6  12.5   6.9
  9750   8.9  48.0  155   7  3   9.2   5.0 |   9.9  49.8  150  11  5   9.0   4.9
  9500   9.7  49.5  155   6  3  10.1   5.5 |  10.6  51.1  150  10  5   9.7   5.3
  9250  10.4  50.7  155   6  3   9.3   5.1 |  11.3  52.3  150  10  5  10.2   5.6
  9000  11.1  52.0  155   6  3   9.5   5.2 |  12.1  53.8  150  10  5   9.9   5.5
  8750  11.8  53.2  155   6  3  10.3   5.7 |  12.8  55.0  150   9  5   9.0   5.0
  8500  12.6  54.7  155   6  3   9.7   5.3 |  13.5  56.3  150   9  5   8.9   4.9
  8250  13.3  55.9  160   6  3  11.2   6.2 |  14.2  57.6  145   9  4  10.3   5.6
  8000  14.2  57.6  155   5  3  11.0   6.0 |  15.0  59.0  150   8  4  10.3   5.7
  7750  14.9  58.8  155   5  3   8.9   4.9 |  15.6  60.1  145   7  4   8.5   4.7
  7500  15.6  60.1  155   5  3   8.8   4.8 |  16.3  61.3  145   6  3   8.5   4.6
  7250  16.3  61.3  160   5  3  10.5   5.7 |  16.9  62.4  145   5  3   9.5   5.2
  7000  17.1  62.8  160   5  2  11.4   6.3 |  17.7  63.9  140   4  2  10.2   5.6
  6750  17.9  64.2  160   4  2   9.5   5.2 |  18.4  65.1  135   3  2   9.4   5.1
  6500  18.6  65.5  160   4  2   9.5   5.2 |  19.1  66.4  130   3  1   9.2   5.1
  6250  19.4  66.9  160   4  2  11.0   6.0 |  19.8  67.6  120   2  1   9.6   5.2
  6000  20.2  68.4  160   4  2  11.6   6.4 |  20.5  68.9  105   2  1   9.7   5.3
  5750  21.0  69.8  160   4  2   9.7   5.3 |  21.2  70.2  070   1  1   9.4   5.2
  5500  21.8  71.2  160   3  2  13.9   7.6 |  21.9  71.4  045   1  1  10.6   5.8
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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