Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 160052
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1851 MDT Friday, August 15, 2014

This forecast is for Saturday, August 16, 2014:

If the trigger temperature of 82.0 F/27.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1063 ft/min (5.4 m/s)
   Maximum height of thermals.................. 17984 ft MSL (12697 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15029 ft MSL (9742 ft AGL)
Thermal soaring outlook for Sunday 08/17....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 21809 ft MSL (16522 ft AGL)
Wave soaring outlook for Sunday 08/17.......... Poor

Remarks...

Sunrise/Sunset.................... 06:12:29 / 19:55:27 MDT
Total possible sunshine........... 13 hr 42 min 58 sec (822 min 58 sec)
Altitude of sun at 13:03:37 MDT... 63.80 degrees

Upper air data from numerical model forecast valid on 08/16/2014 at 0600 MDT

Freezing level.................. 15503 ft MSL (10216 ft AGL)
Convective condensation level... 15110 ft MSL (9823 ft AGL)
Lifted condensation level....... 16426 ft MSL (11138 ft AGL)
Lifted index.................... -2.9
K index......................... +20.1

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  -64.3 -83.7   290   11    6   0.3   0.2      M     M       M      M    M
 45000  -61.7 -79.1   290   19   10   5.0   2.7      M     M       M      M    M
 40000  -53.8 -64.8   280   30   15   7.6   4.2      M     M       M      M    M
 38000  -49.2 -56.6   280   30   16   7.6   4.2      M     M       M      M    M
 36000  -44.6 -48.3   275   31   16   7.5   4.1      M     M       M      M    M
 34000  -39.0 -38.2   280   26   14   8.3   4.6      M     M       M      M    M
 32000  -34.0 -29.2   285   22   11   8.4   4.6      M     M       M      M    M
 30000  -29.6 -21.3   280   17    9   7.2   4.0   46.2 115.2     9.8      M    M
 29000  -27.4 -17.3   275   14    7   7.3   4.0   45.3 113.5     9.2      M    M
 28000  -25.3 -13.5   270   12    6   7.0   3.8   44.4 112.0     8.6      M    M
 27000  -23.2  -9.8   275   11    6   7.0   3.8   43.3 109.9     7.8      M    M
 26000  -21.1  -6.0   280   10    5   7.0   3.8   42.2 108.0     7.1      M    M
 25000  -19.0  -2.2   290    8    4   7.2   3.9   41.3 106.4     6.4      M    M
 24000  -16.7   1.9   300    9    5   7.8   4.3   40.5 104.8     5.8      M    M
 23000  -14.3   6.3   310   11    6   7.8   4.3   39.7 103.5     5.3      M    M
 22000  -12.0  10.4   315   13    7   7.2   3.9   39.1 102.5     4.8      M    M
 21000  -10.1  13.8   320   14    7   6.0   3.3   37.8 100.0     3.7      M    M
 20000   -8.3  17.1   320   15    8   6.0   3.3   36.5  97.6     2.6      M    M
 19500   -7.4  18.7   320   15    8   6.1   3.4   35.8  96.5     2.1      M    M
 19000   -6.6  20.1   320   15    8   5.1   2.8   35.1  95.3     1.5      M    M
 18500   -5.8  21.6   325   14    7   5.3   2.9   34.4  93.8     0.8      M    M
 18000   -5.0  23.0   325   13    7   5.6   3.1   33.6  92.5     0.2      M    M
 17500   -4.2  24.4   330   13    7   6.0   3.3   32.9  91.3    -0.5   1133  5.8
 17000   -2.9  26.8   330   13    7   6.6   3.6   32.0  89.6    -1.3   1071  5.4
 16500   -1.8  28.8   335   13    7   7.2   4.0   31.5  88.8    -1.8   1026  5.2
 16000   -0.8  30.6   335   13    7   7.4   4.1   31.1  88.1    -2.3    981  5.0
 15500    0.2  32.4   335   13    7   7.9   4.3   30.8  87.4    -2.7    934  4.7
 15000    1.3  34.3   335   13    7   7.9   4.4   30.5  86.9    -3.1    887  4.5
 14500    2.5  36.5   335   13    7   9.0   4.9   30.3  86.5    -3.4    837  4.3
 14000    3.8  38.8   335   13    7   9.0   5.0   30.1  86.3    -3.6    783  4.0
 13500    5.1  41.2   335   12    6   9.1   5.0   30.0  86.1    -3.8    730  3.7
 13000    6.4  43.5   335   12    6   9.1   5.0   29.9  85.9    -4.0    675  3.4
 12500    7.7  45.9   335   11    6   9.0   5.0   29.8  85.7    -4.1    621  3.2
 12000    9.0  48.2   335   11    6   9.0   4.9   29.7  85.5    -4.3    567  2.9
 11500   10.3  50.5   335   10    5   8.9   4.9   29.6  85.2    -4.5    513  2.6
 11000   11.6  52.9   335   10    5   8.6   4.7   29.4  85.0    -4.7    460  2.3
 10500   12.9  55.2   335   10    5   4.7   2.6   29.3  84.8    -4.9    407  2.1
 10250   13.1  55.6   335   10    5   6.1   3.4   28.8  83.8    -5.4    393  2.0
 10000   13.9  57.0   335   10    5  12.2   6.7   28.9  83.9    -5.4    361  1.8
  9750   14.7  58.5   335   11    6  11.1   6.1   29.0  84.1    -5.3    330  1.7
  9500   15.5  59.9   335   11    6   9.4   5.2   29.1  84.3    -5.2    298  1.5
  9250   16.1  61.0   335   11    6   7.5   4.1   28.9  84.0    -5.4    273  1.4
  9000   16.7  62.1   335   11    6   9.5   5.2   28.8  83.9    -5.5    247  1.3
  8750   17.5  63.5   335   12    6  10.0   5.5   28.8  83.9    -5.5    217  1.1
  8500   18.2  64.8   335   12    6   9.7   5.3   28.8  83.9    -5.5    188  1.0
  8250   18.9  66.0   335   12    6   9.4   5.2   28.8  83.9    -5.6    160  0.8
  8000   19.6  67.3   335   13    7   9.7   5.3   28.8  83.9    -5.6    131  0.7
  7750   20.3  68.5   330   13    7   9.6   5.3   28.8  83.8    -5.6    103  0.5
  7500   21.0  69.8   330   13    7   8.7   4.8   28.8  83.8    -5.7     75  0.4
  7250   21.6  70.9   325   14    7   7.8   4.3   28.6  83.6    -5.9     50  0.3
  7000   22.2  72.0   320   15    8   9.0   5.0   28.5  83.3    -6.0     24  0.1
  6750   22.8  73.0   315   16    8   5.1   2.8   28.4  83.1    -6.2      M    M
  6500   22.8  73.0   310   17    8  -0.1  -0.1   27.8  82.0    -6.9      M    M
  6250   22.6  72.7   305   16    8  -5.6  -3.0   26.9  80.4    -7.8      M    M
  6000   22.4  72.3   300   16    8  11.1   6.1   26.0  78.8    -8.8      M    M
  5750   23.4  74.1   295   17    9  -3.8  -2.1   26.3  79.4    -8.5      M    M
  5500   20.2  68.4   280   10    5 -75.5 -41.4   22.6  72.7   -12.4     39  0.2

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

           08/16/2014 at 0900 MDT          |       08/16/2014 at 1200 MDT
                                           |
K index... +25.4  LI... -0.5               | K index... +18.2  LI... +0.4
CAPE... +122.1  CIN... -67.8               | CAPE... +20.9  CIN... -44.4
                                           |
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 -64.8 -84.6  285  10  5  -0.0  -0.0 | -64.7 -84.5  270  13  6   0.0   0.0
 45000 -62.2 -80.0  285  18  9   5.7   3.2 | -62.2 -80.0  270  19 10   5.6   3.1
 40000 -53.3 -63.9  280  27 14   7.0   3.8 | -53.0 -63.4  285  23 12   7.2   3.9
 38000 -49.1 -56.4  280  27 14   7.0   3.9 | -48.7 -55.7  285  23 12   7.2   3.9
 36000 -44.8 -48.6  280  26 14   6.9   3.8 | -44.4 -47.9  280  23 12   7.3   4.0
 34000 -39.4 -38.9  285  23 12   8.3   4.5 | -39.6 -39.3  280  21 11   8.1   4.4
 32000 -34.4 -29.9  285  20 10   8.3   4.5 | -34.8 -30.6  280  19 10   8.2   4.5
 30000 -30.0 -22.0  285  18  9   7.2   3.9 | -30.6 -23.1  285  18  9   6.9   3.8
 29000 -27.9 -18.2  280  16  8   7.2   4.0 | -28.5 -19.3  290  17  9   6.9   3.8
 28000 -25.7 -14.3  280  15  8   7.0   3.9 | -26.4 -15.5  290  17  9   7.0   3.8
 27000 -23.6 -10.5  285  15  7   7.0   3.9 | -23.8 -10.8  290  17  9   7.0   3.8
 26000 -21.5  -6.7  290  14  7   7.0   3.9 | -21.7  -7.1  290  18  9   7.0   3.8
 25000 -19.4  -2.9  290  14  7   7.2   4.0 | -19.7  -3.5  290  19 10   7.5   4.1
 24000 -17.1   1.2  300  13  7   7.7   4.2 | -17.3   0.9  290  18  9   7.9   4.4
 23000 -14.8   5.4  305  13  7   7.7   4.2 | -14.9   5.2  295  17  9   7.9   4.4
 22000 -12.4   9.7  315  13  7   7.2   3.9 | -12.6   9.3  300  16  8   7.2   4.0
 21000 -10.5  13.1  320  13  7   6.3   3.5 | -10.5  13.1  300  15  8   6.9   3.8
 20000  -8.6  16.5  320  14  7   6.4   3.5 |  -8.4  16.9  300  14  7   6.9   3.8
 19500  -7.7  18.1  325  14  7   6.4   3.5 |  -7.4  18.7  305  14  7   6.8   3.7
 19000  -6.8  19.8  325  13  7   5.6   3.1 |  -6.5  20.3  300  14  7   6.0   3.3
 18500  -6.0  21.2  320  12  6   5.7   3.1 |  -5.6  21.9  300  13  7   6.1   3.3
 18000  -5.1  22.8  320  11  6   5.6   3.1 |  -4.7  23.5  295  13  7   5.7   3.1
 17500  -4.4  24.1  315  10  5   5.4   3.0 |  -3.9  25.0  295  13  7   5.6   3.1
 17000  -3.6  25.5  315   9  5   5.5   3.0 |  -3.1  26.4  290  13  7   5.8   3.2
 16500  -2.3  27.9  315   9  4   6.8   3.7 |  -2.3  27.9  290  12  6   6.3   3.5
 16000  -1.4  29.5  315   9  4   7.0   3.9 |  -1.4  29.5  285  12  6   6.3   3.5
 15500  -0.4  31.3  320   8  4   7.7   4.2 |  -0.5  31.1  285  11  6   7.4   4.1
 15000   0.7  33.3  325   8  4   7.7   4.2 |   0.6  33.1  285  10  5   7.5   4.1
 14500   1.8  35.2  330   8  4   9.0   4.9 |   1.7  35.1  280   8  4   8.3   4.6
 14000   3.1  37.6  335   9  5   8.9   4.9 |   3.6  38.5  285   8  4   8.9   4.9
 13500   4.4  39.9  340  10  5   9.6   5.3 |   4.9  40.8  290   7  4   9.4   5.2
 13000   5.8  42.4  340  11  6   9.8   5.4 |   6.3  43.3  300   7  4   9.4   5.2
 12500   7.2  45.0  340  12  6   9.6   5.3 |   7.7  45.9  310   8  4   9.6   5.3
 12000   8.6  47.5  340  13  7   9.5   5.2 |   9.2  48.6  315   9  5   9.7   5.3
 11500  10.1  50.2  340  15  8   9.5   5.2 |  10.6  51.1  320  10  5   9.0   4.9
 11000  11.5  52.7  340  16  8   9.1   5.0 |  11.9  53.4  325  11  6   8.7   4.8
 10500  12.9  55.2  340  16  8   4.4   2.4 |  13.0  55.4  330  12  6   4.3   2.4
 10250  13.1  55.6  340  17  9   6.2   3.4 |  13.3  55.9  330  12  6   7.3   4.0
 10000  14.0  57.2  340  17  9  13.4   7.4 |  14.1  57.4  330  11  6  12.5   6.8
  9750  14.9  58.8  340  17  9  12.1   6.7 |  14.8  58.6  330  10  5  11.2   6.1
  9500  15.7  60.3  340  18  9   8.9   4.9 |  15.6  60.1  330  10  5   8.6   4.7
  9250  16.2  61.2  340  18  9   6.5   3.6 |  16.1  61.0  330  10  5   7.9   4.3
  9000  16.9  62.4  340  18  9  10.4   5.7 |  16.8  62.2  330  10  5  11.0   6.0
  8750  17.7  63.9  340  17  9  11.3   6.2 |  17.6  63.7  330  10  5  11.4   6.2
  8500  18.5  65.3  340  17  9   9.2   5.1 |  18.4  65.1  330  10  5  10.3   5.7
  8250  19.1  66.4  340  17  9   7.6   4.2 |  19.2  66.6  330  10  5   9.9   5.4
  8000  19.7  67.5  340  17  9   9.2   5.0 |  19.9  67.8  330   9  5  10.2   5.6
  7750  20.4  68.7  340  17  9   9.7   5.3 |  20.7  69.3  330  10  5  10.1   5.5
  7500  21.1  70.0  335  17  9   8.2   4.5 |  21.4  70.5  330  10  5   9.8   5.4
  7250  21.7  71.1  335  17  9   7.4   4.1 |  22.1  71.8  330   9  5   9.7   5.3
  7000  22.2  72.0  330  18  9   8.7   4.8 |  22.9  73.2  330   9  5  10.0   5.5
  6750  22.9  73.2  330  18  9   5.0   2.8 |  23.6  74.5  330   9  5  10.3   5.7
  6500  22.9  73.2  325  16  8   0.5   0.3 |  24.4  75.9  330   9  5  10.4   5.7
  6250  22.8  73.0  315  15  8  -0.9  -0.5 |  25.2  77.4  330   9  5   9.9   5.4
  6000  22.8  73.0  305  13  7   5.2   2.8 |  25.9  78.6  330   9  5  11.9   6.5
  5750  23.5  74.3  305  12  6  11.2   6.1 |  27.0  80.6  330   9  5  17.6   9.6
  5500  23.9  75.0  295   9  5   3.1   1.7 |  28.4  83.1  330   9  4  20.6  11.3

           08/16/2014 at 1500 MDT          |       08/16/2014 at 1800 MDT
                                           |
K index... +22.2  LI... +0.4               | K index... +23.9  LI... -0.3
CAPE... +54.6  CIN... -68.0                | CAPE... +96.3  CIN... -55.9
                                           |
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 -64.5 -84.1  260  14  7  -0.2  -0.1 | -64.7 -84.5  280  20 10  -0.2  -0.1
 45000 -62.3 -80.1  260  21 11   5.4   3.0 | -62.3 -80.1  280  32 16   5.7   3.1
 40000 -53.2 -63.8  280  21 11   7.8   4.3 | -52.9 -63.2  285  28 15   7.5   4.1
 38000 -48.6 -55.5  280  20 10   7.8   4.3 | -48.5 -55.3  285  25 13   7.5   4.1
 36000 -44.0 -47.2  285  19 10   7.7   4.2 | -44.0 -47.2  285  23 12   7.5   4.1
 34000 -39.4 -38.9  285  19 10   7.6   4.2 | -39.6 -39.3  290  23 12   7.3   4.0
 32000 -34.8 -30.6  285  20 10   7.7   4.2 | -35.2 -31.4  290  23 12   7.3   4.0
 30000 -30.5 -22.9  290  19 10   7.1   3.9 | -30.8 -23.4  300  23 12   7.3   4.0
 29000 -28.4 -19.1  290  18  9   7.1   3.9 | -28.6 -19.5  305  23 12   7.3   4.0
 28000 -25.8 -14.4  295  18  9   6.6   3.6 | -25.9 -14.6  310  23 12   6.8   3.7
 27000 -23.8 -10.8  295  19 10   6.7   3.7 | -23.9 -11.0  310  23 12   6.9   3.8
 26000 -21.8  -7.2  300  19 10   6.7   3.7 | -21.8  -7.2  310  22 11   6.9   3.8
 25000 -19.8  -3.6  300  20 10   7.5   4.1 | -19.8  -3.6  315  22 11   7.5   4.1
 24000 -17.3   0.9  300  20 10   8.1   4.5 | -17.4   0.7  310  22 11   7.9   4.3
 23000 -14.9   5.2  300  19 10   8.1   4.5 | -15.1   4.8  310  22 12   7.9   4.3
 22000 -12.5   9.5  300  19 10   7.3   4.0 | -12.7   9.1  310  23 12   7.2   4.0
 21000 -10.4  13.3  300  20 10   7.0   3.8 | -10.7  12.7  310  22 11   7.0   3.8
 20000  -8.3  17.1  300  20 10   7.0   3.8 |  -8.6  16.5  305  22 11   7.0   3.8
 19500  -7.3  18.9  300  20 10   6.9   3.8 |  -7.5  18.5  305  22 11   7.0   3.8
 19000  -6.3  20.7  300  21 11   6.7   3.7 |  -6.5  20.3  300  22 11   7.1   3.9
 18500  -5.3  22.5  300  21 11   6.7   3.7 |  -5.5  22.1  300  22 11   7.1   3.9
 18000  -4.3  24.3  300  22 11   6.7   3.7 |  -4.4  24.1  295  22 12   7.9   4.3
 17500  -3.4  25.9  300  23 12   6.7   3.7 |  -3.3  26.1  295  22 12   8.2   4.5
 17000  -2.4  27.7  300  24 12   6.9   3.8 |  -2.1  28.2  295  22 12   8.2   4.5
 16500  -1.4  29.5  300  24 12   7.7   4.2 |  -0.9  30.4  295  22 11   8.3   4.6
 16000  -0.3  31.5  300  23 12   7.9   4.3 |   0.2  32.4  295  21 11   8.4   4.6
 15500   0.8  33.4  300  23 12   8.3   4.6 |   1.4  34.5  295  19 10   8.4   4.6
 15000   1.9  35.4  305  21 11   8.4   4.6 |   2.5  36.5  295  18  9   8.5   4.7
 14500   3.0  37.4  305  19 10   8.4   4.6 |   3.7  38.7  300  16  8   8.5   4.7
 14000   4.8  40.6  310  17  9   8.3   4.6 |   5.6  42.1  300  12  6   8.4   4.6
 13500   6.0  42.8  310  15  8   8.5   4.7 |   6.8  44.2  300  10  5   8.8   4.8
 13000   7.2  45.0  315  13  7   8.5   4.7 |   8.1  46.6  300   7  4   8.9   4.9
 12500   8.5  47.3  315  11  6   8.8   4.8 |   9.4  48.9  300   5  3   8.1   4.4
 12000   9.9  49.8  320   9  5   8.9   4.9 |  10.6  51.1  315   3  2   7.9   4.3
 11500  11.2  52.2  325   8  4   8.4   4.6 |  11.7  53.1  355   2  1   8.2   4.5
 11000  12.4  54.3  330   6  3   8.2   4.5 |  12.9  55.2  010   3  1   8.3   4.5
 10500  13.5  56.3  335   5  2   4.0   2.2 |  14.1  57.4  020   3  2   4.1   2.3
 10250  13.8  56.8  335   5  2   7.5   4.1 |  14.4  57.9  020   3  2   6.9   3.8
 10000  14.7  58.5  340   4  2  13.2   7.2 |  15.2  59.4  020   3  2  12.6   6.9
  9750  15.6  60.1  340   4  2  11.8   6.5 |  16.0  60.8  020   4  2  11.5   6.3
  9500  16.4  61.5  340   4  2   9.5   5.2 |  16.8  62.2  020   4  2   8.6   4.7
  9250  17.0  62.6  340   4  2   8.5   4.7 |  17.3  63.1  015   4  2   7.6   4.1
  9000  17.8  64.0  340   4  2  11.0   6.1 |  18.1  64.6  015   4  2  11.1   6.1
  8750  18.6  65.5  340   4  2  11.1   6.1 |  18.9  66.0  015   4  2  11.3   6.2
  8500  19.4  66.9  340   4  2  10.0   5.5 |  19.7  67.5  010   4  2  10.2   5.6
  8250  20.1  68.2  340   4  2   9.2   5.1 |  20.4  68.7  010   4  2   9.5   5.2
  8000  20.8  69.4  340   4  2  10.1   5.5 |  21.1  70.0  010   4  2   9.5   5.2
  7750  21.6  70.9  340   4  2  10.6   5.8 |  21.8  71.2  010   4  2   9.6   5.2
  7500  22.3  72.1  340   4  2  10.3   5.7 |  22.6  72.7  005   4  2  10.0   5.5
  7250  23.1  73.6  340   4  2  10.5   5.7 |  23.3  73.9  005   4  2  10.4   5.7
  7000  23.9  75.0  335   4  2   9.9   5.4 |  24.1  75.4  005   5  2   9.7   5.3
  6750  24.6  76.3  335   4  2   9.8   5.4 |  24.8  76.6  005   5  2   9.6   5.3
  6500  25.4  77.7  335   4  2  10.5   5.8 |  25.5  77.9  360   5  2  10.4   5.7
  6250  26.2  79.2  335   4  2  10.6   5.8 |  26.3  79.3  360   5  2  10.9   6.0
  6000  27.0  80.6  335   4  2  10.5   5.7 |  27.1  80.8  360   5  2   9.3   5.1
  5750  27.8  82.0  335   4  2  15.8   8.7 |  27.8  82.0  360   5  2  11.0   6.0
  5500  29.4  84.9  335   4  2  24.8  13.6 |  28.9  84.0  355   5  2  18.4  10.1
________________________________________________________________________________

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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