Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 161324
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0724 MDT Saturday, August 16, 2014

This forecast is for Saturday, August 16, 2014:

If the trigger temperature of 82.5 F/28.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1377 ft/min (7.0 m/s)
   Maximum height of thermals.................. 18016 ft MSL (12731 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 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................. 17407 ft MSL (12122 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)......... 17805 ft MSL (12520 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18296 ft MSL (13011 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 rawinsonde observation taken on 08/16/2014 at 0600 MDT

Freezing level.................. 15027 ft MSL (9742 ft AGL)
Convective condensation level... 16016 ft MSL (10731 ft AGL)
Lifted condensation level....... 17679 ft MSL (12393 ft AGL)
Lifted index.................... -0.8
K index......................... +25.6

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   285   18    9  -1.7  -0.9   85.1 185.2    30.1      M    M
 45000  -61.4 -78.5   290   18    9   5.0   2.8   66.2 151.1    20.5      M    M
 40000  -54.0 -65.2   265   25   13   8.9   4.9   53.7 128.7    13.7      M    M
 38000  -49.2 -56.6   265   23   12   7.9   4.3   52.2 125.9    13.0      M    M
 36000  -44.2 -47.6   260   21   11   9.0   4.9   51.0 123.8    12.5      M    M
 34000  -39.1 -38.4   265   20   10   8.4   4.6   49.9 121.9    12.0      M    M
 32000  -34.4 -29.9   275   20   10   7.3   4.0   48.5 119.3    11.3      M    M
 30000  -29.6 -21.3   270   14    7   9.7   5.3   47.1 116.9    10.5      M    M
 29000  -26.7 -16.1   280   12    6   6.6   3.6   47.1 116.8    10.6      M    M
 28000  -25.4 -13.7   325   10    5   6.9   3.8   45.0 113.1     9.1      M    M
 27000  -23.0  -9.4   325    8    4   8.4   4.6   43.5 110.3     8.0      M    M
 26000  -20.6  -5.1   320    7    4   7.5   4.1   42.8 109.0     7.5      M    M
 25000  -18.3  -0.9   340    9    5   7.7   4.2   42.0 107.5     7.0      M    M
 24000  -16.5   2.3   330   12    6   6.5   3.6   40.7 105.2     6.0      M    M
 23000  -14.9   5.2   335   12    6   4.8   2.6   39.1 102.4     4.7      M    M
 22000  -12.8   9.0   340   11    6   8.0   4.4   38.0 100.5     3.9      M    M
 21000  -10.4  13.3   350   11    6   7.9   4.4   37.3  99.2     3.4      M    M
 20000   -8.0  17.6   355   11    6   8.1   4.4   36.8  98.2     2.9      M    M
 19500   -7.2  19.0   340   12    6   4.7   2.6   36.2  97.1     2.4      M    M
 19000   -6.2  20.8   330   14    7   6.2   3.4   35.5  95.9     1.9      M    M
 18500   -5.6  21.9   330   17    9   2.9   1.6   34.6  94.3     1.0      M    M
 18000   -5.1  22.8   325   21   11   2.9   1.6   33.5  92.3     0.1      M    M
 17500   -6.2  20.8   325   19   10  -5.4  -2.9   30.9  87.6    -2.5   1197  6.1
 17000   -5.8  21.6   325   18    9   9.2   5.0   30.0  86.0    -3.6   1170  5.9
 16500   -4.3  24.3   320   16    8   9.7   5.3   30.1  86.2    -3.6   1111  5.6
 16000   -2.9  26.8   320   14    7   9.5   5.2   30.0  86.1    -3.7   1054  5.4
 15500   -1.5  29.3   320   13    7   9.4   5.2   30.0  86.0    -3.7    998  5.1
 15000   -0.2  31.6   320   13    7   9.1   5.0   29.9  85.8    -3.9    943  4.8
 14500    1.1  34.0   320   12    6   9.2   5.1   29.8  85.6    -4.1    890  4.5
 14000    2.5  36.5   320   11    6   9.2   5.1   29.7  85.5    -4.2    834  4.2
 13500    4.5  40.1   325   10    5   9.2   5.1   29.6  85.2    -4.3    749  3.8
 13000    5.9  42.6   335   10    5   9.2   5.1   29.5  85.1    -4.4    693  3.5
 12500    7.3  45.1   340   10    5   9.2   5.0   29.4  84.9    -4.5    637  3.2
 12000    8.7  47.7   345   10    5   9.6   5.2   29.4  84.9    -4.6    580  2.9
 11500   10.1  50.2   345    9    5   9.6   5.2   29.3  84.8    -4.6    523  2.7
 11000   11.6  52.9   350    9    4   9.6   5.2   29.3  84.7    -4.7    465  2.4
 10500   13.0  55.4   350    8    4   9.3   5.1   29.3  84.7    -4.7    407  2.1
 10250   13.7  56.7   355    8    4   9.0   4.9   29.2  84.6    -4.8    380  1.9
 10000   14.3  57.7   360    9    5   9.1   5.0   29.2  84.5    -4.9    353  1.8
  9750   15.0  59.0   360    9    5   9.1   5.0   29.1  84.4    -5.0    325  1.7
  9500   15.7  60.3   005   10    5   9.1   5.0   29.1  84.3    -5.0    298  1.5
  9250   16.3  61.3   010   10    5   9.0   5.0   29.0  84.2    -5.1    270  1.4
  9000   17.0  62.6   010   11    6   9.2   5.0   29.0  84.2    -5.1    243  1.2
  8750   17.7  63.9   360   10    5   8.6   4.7   28.9  84.0    -5.2    216  1.1
  8500   18.3  64.9   350    9    5   7.9   4.3   28.8  83.8    -5.4    190  1.0
  8250   18.9  66.0   340    8    4   7.9   4.3   28.6  83.6    -5.5    165  0.8
  8000   19.4  66.9   330    8    4   7.9   4.3   28.5  83.3    -5.7    141  0.7
  7750   20.0  68.0   330    8    4   7.9   4.3   28.4  83.1    -5.8    116  0.6
  7500   20.6  69.1   330    7    4   7.9   4.4   28.2  82.8    -6.0     91  0.5
  7250   21.2  70.2   325    7    4   7.7   4.2   28.1  82.5    -6.2     66  0.3
  7000   21.8  71.2   325    7    4   8.5   4.7   27.9  82.3    -6.3     41  0.2
  6750   22.4  72.3   320    7    4   5.6   3.1   27.8  82.0    -6.5     16  0.1
  6500   22.6  72.7   315    7    4   2.6   1.4   27.3  81.1    -7.0      2  0.0
  6250   22.8  73.0   305    7    4   2.5   1.4   26.8  80.2    -7.6      M    M
  6000   23.0  73.4   300    7    4   4.9   2.7   26.3  79.3    -8.1      M    M
  5750   23.2  73.8   300    5    2  -4.4  -2.4   25.8  78.4    -8.7      M    M
  5500   21.3  70.3   300    2    1 -42.6 -23.4   23.4  74.1   -11.3     10  0.1

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

           08/16/2014 at 0900 MDT          |       08/16/2014 at 1200 MDT
                                           |
K index... +28.0  LI... -1.6               | K index... +23.9  LI... -2.5
CAPE... +109.8  CIN... -104.8              | CAPE... +186.7  CIN... -24.0
                                           |
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 -64.1 -83.4  285  14  7  -0.0  -0.0 | -64.1 -83.4  290  15  8   0.0   0.0
 45000 -61.6 -78.9  285  19 10   5.4   3.0 | -61.7 -79.1  285  21 11   5.3   2.9
 40000 -53.2 -63.8  280  26 13   6.9   3.8 | -53.0 -63.4  280  23 12   6.9   3.8
 38000 -49.0 -56.2  280  23 12   7.0   3.8 | -48.9 -56.0  275  21 11   6.9   3.8
 36000 -44.8 -48.6  275  21 11   6.8   3.8 | -44.8 -48.6  275  20 11   7.1   3.9
 34000 -39.4 -38.9  275  18  9   8.1   4.5 | -40.0 -40.0  270  18  9   8.0   4.4
 32000 -34.5 -30.1  275  15  8   8.4   4.6 | -35.2 -31.4  270  16  8   8.0   4.4
 30000 -30.1 -22.2  280  10  5   7.4   4.1 | -30.8 -23.4  275  12  6   7.4   4.1
 29000 -27.9 -18.2  285   8  4   7.4   4.1 | -28.6 -19.5  280  10  5   7.4   4.1
 28000 -25.6 -14.1  295   5  3   7.4   4.1 | -26.4 -15.5  285   8  4   7.4   4.1
 27000 -23.4 -10.1  305   6  3   7.4   4.1 | -23.6 -10.5  300   9  4   7.4   4.0
 26000 -21.2  -6.2  315   6  3   7.4   4.1 | -21.4  -6.5  310   9  5   7.4   4.0
 25000 -18.9  -2.0  325   6  3   7.2   4.0 | -19.2  -2.6  320  10  5   7.4   4.1
 24000 -16.9   1.6  315   5  3   6.7   3.7 | -17.0   1.4  310  10  5   7.4   4.1
 23000 -14.9   5.2  300   5  2   6.7   3.7 | -14.7   5.5  295  11  5   7.4   4.1
 22000 -12.9   8.8  280   4  2   6.2   3.4 | -12.6   9.3  290  11  6   5.5   3.0
 21000 -11.3  11.7  300   4  2   5.4   3.0 | -11.3  11.7  285  11  6   4.6   2.5
 20000  -9.7  14.5  320   4  2   5.4   3.0 |  -9.9  14.2  280  11  6   4.7   2.6
 19500  -8.8  16.2  330   4  2   5.3   2.9 |  -9.2  15.4  280  11  6   5.1   2.8
 19000  -8.0  17.6  345   5  3   6.1   3.3 |  -8.3  17.1  280  11  5   7.5   4.1
 18500  -7.1  19.2  350   7  3   6.1   3.3 |  -7.3  18.9  285  11  5   7.5   4.1
 18000  -6.2  20.8  355   9  5   6.8   3.7 |  -6.2  20.8  285  10  5   8.5   4.7
 17500  -5.2  22.6  355  10  5   7.8   4.3 |  -4.9  23.2  290   9  5   8.9   4.9
 17000  -3.6  25.5  350  11  6   8.2   4.5 |  -3.7  25.3  295   8  4   9.0   5.0
 16500  -2.4  27.7  350  12  6   8.4   4.6 |  -2.5  27.5  300   8  4   8.8   4.8
 16000  -1.3  29.7  345  12  6   8.5   4.7 |  -1.3  29.7  305   7  4   9.0   5.0
 15500  -0.1  31.8  345  12  6   8.4   4.6 |  -0.1  31.8  305   7  3   7.4   4.1
 15000   1.1  34.0  345  13  7   8.4   4.6 |   1.0  33.8  305   7  3   7.4   4.1
 14500   2.4  36.3  340  13  7   9.3   5.1 |   2.0  35.6  310   7  3   8.2   4.5
 14000   3.8  38.8  340  12  6   9.3   5.1 |   4.0  39.2  320   6  3   8.7   4.8
 13500   5.1  41.2  335  12  6   9.2   5.1 |   5.3  41.5  330   7  3   9.1   5.0
 13000   6.5  43.7  335  12  6   9.2   5.1 |   6.7  44.1  340   7  4   9.1   5.0
 12500   7.9  46.2  335  12  6   9.2   5.1 |   8.1  46.6  350   8  4   9.1   5.0
 12000   9.2  48.6  335  13  7   9.2   5.1 |   9.5  49.1  355  10  5   9.1   5.0
 11500  10.6  51.1  335  14  7   9.1   5.0 |  10.9  51.6  355  13  6   9.0   4.9
 11000  11.9  53.4  335  14  7   8.7   4.7 |  12.3  54.1  355  14  7   9.0   5.0
 10500  13.3  55.9  330  15  8   4.5   2.5 |  13.6  56.5  355  16  8   4.1   2.3
 10250  13.5  56.3  330  15  8   6.2   3.4 |  13.8  56.8  355  16  8   7.2   4.0
 10000  14.4  57.9  330  15  8  12.8   7.0 |  14.7  58.5  355  16  8  12.7   7.0
  9750  15.2  59.4  330  15  8  11.8   6.5 |  15.6  60.1  355  17  9  11.0   6.1
  9500  16.1  61.0  330  15  8   8.5   4.7 |  16.3  61.3  355  17  9   7.8   4.3
  9250  16.5  61.7  330  15  8   6.0   3.3 |  16.8  62.2  355  17  9   6.4   3.5
  9000  17.1  62.8  330  15  8   9.9   5.4 |  17.3  63.1  355  16  8   9.4   5.1
  8750  17.9  64.2  325  15  8  10.8   5.9 |  18.0  64.4  355  15  8   9.7   5.3
  8500  18.7  65.7  325  15  8   9.3   5.1 |  18.6  65.5  355  14  7   8.8   4.8
  8250  19.3  66.7  325  15  8   8.5   4.6 |  19.1  66.4  355  12  6   8.0   4.4
  8000  19.9  67.8  325  14  7   8.6   4.7 |  19.7  67.5  355  11  6  10.1   5.5
  7750  20.5  68.9  320  14  7   8.3   4.5 |  20.5  68.9  360  10  5  11.3   6.2
  7500  21.1  70.0  320  14  7   8.2   4.5 |  21.2  70.2  360  10  5  10.0   5.5
  7250  21.7  71.1  315  15  8   7.9   4.3 |  22.0  71.6  360   9  5  10.0   5.5
  7000  22.3  72.1  315  15  8   8.8   4.8 |  22.7  72.9  355   9  5  10.0   5.5
  6750  22.9  73.2  315  16  8   5.7   3.1 |  23.4  74.1  355   9  5  10.3   5.6
  6500  23.1  73.6  310  15  8   1.3   0.7 |  24.2  75.6  355   9  4  10.6   5.8
  6250  23.1  73.6  310  14  7   1.7   0.9 |  25.0  77.0  355   8  4  10.1   5.6
  6000  23.2  73.8  305  13  6   0.5   0.3 |  25.8  78.4  355   8  4  11.6   6.4
  5750  23.0  73.4  300  10  5   0.9   0.5 |  26.8  80.2  355   8  4  16.9   9.3
  5500  23.2  73.8  290   7  3   5.3   2.9 |  28.2  82.8  355   8  4  21.0  11.5

           08/16/2014 at 1500 MDT          |       08/16/2014 at 1800 MDT
                                           |
K index... +24.5  LI... -1.6               | K index... +28.3  LI... -1.4
CAPE... +67.4  CIN... -47.5                | CAPE... +136.1  CIN... -52.4
                                           |
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 -64.1 -83.4  275  14  7   0.1   0.1 | -64.5 -84.1  290  17  9  -0.7  -0.4
 45000 -61.7 -79.1  275  21 11   5.2   2.8 | -62.6 -80.7  290  26 14   5.8   3.2
 40000 -53.0 -63.4  275  22 11   7.6   4.2 | -53.0 -63.4  290  26 13   7.7   4.2
 38000 -48.4 -55.1  275  21 11   7.6   4.2 | -48.5 -55.3  285  25 13   7.7   4.2
 36000 -43.9 -47.0  275  20 10   7.6   4.1 | -43.9 -47.0  280  24 12   7.6   4.2
 34000 -39.5 -39.1  270  19 10   7.3   4.0 | -39.5 -39.1  285  23 12   7.3   4.0
 32000 -35.1 -31.2  270  18  9   7.3   4.0 | -35.2 -31.4  290  22 12   7.2   4.0
 30000 -30.9 -23.6  275  16  8   7.0   3.9 | -30.8 -23.4  295  21 11   7.3   4.0
 29000 -28.8 -19.8  275  15  8   7.0   3.9 | -28.6 -19.5  300  21 11   7.3   4.0
 28000 -26.1 -15.0  275  13  7   7.8   4.3 | -26.4 -15.5  305  21 11   7.5   4.1
 27000 -23.8 -10.8  285  13  7   7.8   4.3 | -23.5 -10.3  305  20 10   7.6   4.2
 26000 -21.4  -6.5  290  13  7   7.8   4.3 | -21.3  -6.3  305  19 10   7.6   4.2
 25000 -19.1  -2.4  295  13  7   7.6   4.2 | -19.0  -2.2  305  19 10   7.5   4.1
 24000 -16.9   1.6  300  15  8   7.5   4.1 | -16.8   1.8  310  20 10   7.5   4.1
 23000 -14.6   5.7  305  17  9   7.5   4.1 | -14.6   5.7  310  20 11   7.5   4.1
 22000 -12.5   9.5  305  19 10   5.7   3.2 | -12.4   9.7  315  21 11   6.2   3.4
 21000 -11.0  12.2  300  21 11   5.1   2.8 | -10.7  12.7  310  22 11   5.7   3.1
 20000  -9.6  14.7  300  22 12   5.3   2.9 |  -9.1  15.6  305  23 12   5.8   3.2
 19500  -8.9  16.0  295  23 12   5.9   3.2 |  -8.2  17.2  305  24 12   6.2   3.4
 19000  -7.8  18.0  295  22 11   8.6   4.7 |  -7.1  19.2  300  24 12   8.6   4.7
 18500  -6.5  20.3  295  21 11   8.4   4.6 |  -5.9  21.4  295  24 12   8.5   4.7
 18000  -5.3  22.5  295  19 10   8.5   4.6 |  -4.7  23.5  295  24 12   8.9   4.9
 17500  -4.1  24.6  295  18 10   8.5   4.7 |  -3.4  25.9  295  22 11   9.0   5.0
 17000  -2.9  26.8  295  18  9   8.6   4.7 |  -2.1  28.2  300  21 11   8.9   4.9
 16500  -1.6  29.1  300  17  9   9.0   4.9 |  -1.0  30.2  300  18  9   7.8   4.3
 16000  -0.3  31.5  300  16  8   9.0   4.9 |   0.1  32.2  300  15  8   7.9   4.3
 15500   1.0  33.8  300  15  8   9.2   5.1 |   1.2  34.2  305  12  6   8.1   4.5
 15000   2.3  36.1  300  14  7   9.3   5.1 |   2.3  36.1  305  10  5   8.2   4.5
 14500   3.6  38.5  305  13  7   8.7   4.8 |   3.5  38.3  305   7  4   8.3   4.6
 14000   5.4  41.7  305  11  6   8.4   4.6 |   5.3  41.5  310   4  2   8.3   4.6
 13500   6.6  43.9  305   9  5   7.7   4.2 |   6.6  43.9  320   2  1   8.3   4.6
 13000   7.7  45.9  305   7  4   7.7   4.2 |   7.8  46.0  320   1  1   8.3   4.6
 12500   8.9  48.0  310   5  3   8.1   4.4 |   9.1  48.4  325   1  0   8.7   4.8
 12000  10.1  50.2  325   4  2   8.2   4.5 |  10.4  50.7  000   0  0   8.8   4.8
 11500  11.3  52.3  340   4  2   8.6   4.7 |  11.8  53.2  000   0  0   8.9   4.9
 11000  12.7  54.9  345   4  2   8.8   4.8 |  13.1  55.6  000   0  0   9.0   4.9
 10500  13.9  57.0  355   4  2   4.5   2.4 |  14.4  57.9  270   1  0   4.6   2.5
 10250  14.2  57.6  355   4  2   7.4   4.0 |  14.6  58.3  280   1  0   7.0   3.8
 10000  15.0  59.0  355   5  2  12.6   6.9 |  15.5  59.9  290   1  1  12.4   6.8
  9750  15.9  60.6  355   5  2  11.4   6.2 |  16.3  61.3  295   1  1  11.4   6.2
  9500  16.7  62.1  355   5  2   9.2   5.1 |  17.1  62.8  300   2  1   8.2   4.5
  9250  17.3  63.1  355   5  2   8.5   4.7 |  17.6  63.7  305   2  1   6.8   3.8
  9000  18.0  64.4  355   5  2  11.1   6.1 |  18.2  64.8  305   2  1  10.2   5.6
  8750  18.9  66.0  355   5  3  11.2   6.2 |  19.0  66.2  310   2  1  10.4   5.7
  8500  19.7  67.5  355   5  3  10.2   5.6 |  19.7  67.5  310   2  1   9.8   5.4
  8250  20.4  68.7  355   5  3   9.7   5.3 |  20.4  68.7  310   2  1   9.3   5.1
  8000  21.1  70.0  355   5  2   9.8   5.4 |  21.2  70.2  310   3  1   9.9   5.4
  7750  21.8  71.2  355   5  3   9.8   5.4 |  21.9  71.4  310   3  1  10.3   5.6
  7500  22.6  72.7  355   5  3   9.9   5.4 |  22.6  72.7  310   3  1  10.1   5.5
  7250  23.3  73.9  355   5  3   9.8   5.4 |  23.4  74.1  310   3  2  10.2   5.6
  7000  24.1  75.4  350   5  3  10.3   5.7 |  24.1  75.4  310   3  2   9.9   5.4
  6750  24.9  76.8  350   5  3  10.9   6.0 |  24.9  76.8  310   3  2   9.9   5.4
  6500  25.7  78.3  350   5  2  10.7   5.9 |  25.6  78.1  310   3  2  10.1   5.6
  6250  26.4  79.5  350   5  2  10.8   5.9 |  26.4  79.5  310   3  2  10.2   5.6
  6000  27.2  81.0  350   5  2  10.3   5.6 |  27.2  81.0  305   3  2  10.1   5.5
  5750  28.1  82.6  350   5  3  14.9   8.2 |  27.9  82.2  305   4  2  12.2   6.7
  5500  29.5  85.1  350   5  3  24.1  13.2 |  28.9  84.0  305   4  2  15.9   8.7
________________________________________________________________________________

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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