Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 141259
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0658 MDT Thursday, August 14, 2014

This forecast is for Thursday, August 14, 2014:

If the trigger temperature of 84.0 F/28.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 399 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10420 ft MSL (5135 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1330 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7253 ft MSL (1968 ft AGL)
Thermal soaring outlook for Friday 08/15....... 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)................ Weak PVA
Potential height of wave....................... 18805 ft MSL (13520 ft AGL)
Wave soaring outlook for Friday 08/15.......... Poor

Remarks...

Sunrise/Sunset.................... 06:10:36 / 19:58:06 MDT
Total possible sunshine........... 13 hr 47 min 30 sec (827 min 30 sec)
Altitude of sun at 13:04:01 MDT... 64.42 degrees

Upper air data from rawinsonde observation taken on 08/14/2014 at 0600 MDT

Freezing level.................. 15913 ft MSL (10628 ft AGL)
Convective condensation level... 14903 ft MSL (9618 ft AGL)
Lifted condensation level....... 14271 ft MSL (8986 ft AGL)
Lifted index.................... -0.3
K index......................... +28.4

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  -68.0 -90.4   325   18    9  -9.2  -5.0   78.6 173.4    28.7      M    M
 45000  -62.6 -80.7   270   33   17   5.0   2.8   63.3 145.9    21.2      M    M
 40000  -52.6 -62.7   250   34   18   7.8   4.3   55.0 130.9    17.2      M    M
 38000  -47.6 -53.7   250   28   14   8.8   4.8   53.8 128.9    16.8      M    M
 36000  -42.1 -43.8   245   21   11   7.6   4.2   53.3 128.0    16.9      M    M
 34000  -37.2 -35.0   230   20   10   7.8   4.3   52.1 125.9    16.4      M    M
 32000  -32.1 -25.8   215   21   11   8.5   4.7   51.2 124.1    16.1      M    M
 30000  -27.5 -17.5   220   18    9   7.4   4.1   49.6 121.2    15.2      M    M
 29000  -24.7 -12.5   220   16    8   7.4   4.1   48.2 118.8    14.4      M    M
 28000  -22.5  -8.5   220   15    8   7.5   4.1   47.3 117.2    13.8      M    M
 27000  -20.4  -4.7   220   14    7   7.5   4.1   46.5 115.8    13.3      M    M
 26000  -18.3  -0.9   215   12    6   6.2   3.4   45.5 114.0    12.6      M    M
 25000  -16.5   2.3   210   11    6   6.5   3.6   44.3 111.7    11.7      M    M
 24000  -14.5   5.9   210   13    6   6.7   3.7   43.0 109.3    10.7      M    M
 23000  -12.6   9.3   205   14    7   6.7   3.7   41.8 107.3     9.8      M    M
 22000  -10.6  12.9   205   16    8   6.8   3.7   40.8 105.4     9.0      M    M
 21000   -8.7  16.3   205   17    9   6.4   3.5   39.9 103.8     8.2      M    M
 20000   -7.2  19.0   205   19   10   5.2   2.8   38.4 101.1     7.0      M    M
 19500   -6.4  20.5   200   19   10   5.2   2.9   37.6  99.6     6.3      M    M
 19000   -5.7  21.7   200   19   10   4.4   2.4   36.7  98.1     5.5      M    M
 18500   -5.1  22.8   195   19   10   4.5   2.5   35.8  96.4     4.7      M    M
 18000   -4.4  24.1   195   18    9   4.4   2.4   34.9  94.8     4.0      M    M
 17500   -3.7  25.3   190   18    9   6.8   3.7   34.1  93.4     3.3      M    M
 17000   -2.6  27.3   185   18    9   7.5   4.1   33.7  92.7     2.9      M    M
 16500   -1.5  29.3   185   18    9   7.6   4.1   33.4  92.0     2.6      M    M
 16000   -0.4  31.3   180   18    9   7.6   4.2   33.0  91.4     2.2      M    M
 15500    0.7  33.3   180   17    9   7.5   4.1   32.7  90.8     1.9      M    M
 15000    1.9  35.4   175   15    8   8.8   4.8   32.4  90.3     1.6      M    M
 14500    3.8  38.8   170   13    7   8.7   4.8   32.1  89.8     1.4      M    M
 14000    5.0  41.0   165   12    6   8.9   4.9   31.9  89.5     1.2      M    M
 13500    6.2  43.2   170   11    6   6.4   3.5   31.6  88.8     0.8      M    M
 13000    7.4  45.3   180   11    6   9.0   5.0   31.3  88.3     0.6      M    M
 12500    8.7  47.7   185   11    6   8.9   4.9   31.2  88.1     0.5      M    M
 12000   10.1  50.2   190   11    6   8.9   4.9   31.1  87.9     0.4      M    M
 11500   11.4  52.5   205   11    6   8.9   4.9   30.9  87.6     0.3      M    M
 11000   12.8  55.0   215   12    6   8.8   4.8   30.8  87.4     0.2      M    M
 10500   14.0  57.2   225   13    7   8.3   4.5   30.5  87.0     0.0      M    M
 10250   14.6  58.3   225   12    6   8.7   4.7   30.4  86.8    -0.1    375  1.9
 10000   15.3  59.5   225   12    6   8.7   4.8   30.4  86.6    -0.2    349  1.8
  9750   15.9  60.6   220   11    6   8.7   4.8   30.3  86.5    -0.3    323  1.6
  9500   16.5  61.7   220   10    5   8.7   4.8   30.2  86.3    -0.4    297  1.5
  9250   17.1  62.8   215   10    5   8.7   4.8   30.1  86.2    -0.5    271  1.4
  9000   17.7  63.9   215    9    5   8.6   4.7   30.0  86.1    -0.6    245  1.2
  8750   18.3  64.9   220    8    4   6.5   3.6   29.9  85.8    -0.8    222  1.1
  8500   18.7  65.7   220    8    4   5.1   2.8   29.5  85.2    -1.2    203  1.0
  8250   19.0  66.2   225    7    4   5.5   3.0   29.2  84.6    -1.5    185  0.9
  8000   19.4  66.9   230    7    4   5.4   3.0   28.9  84.0    -1.9    166  0.8
  7750   19.8  67.6   235    6    3   5.4   3.0   28.5  83.4    -2.3    148  0.7
  7500   20.2  68.4   245    5    2   5.5   3.0   28.2  82.8    -2.6    129  0.7
  7250   20.5  68.9   260    4    2   5.2   2.9   27.9  82.2    -3.0    111  0.6
  7000   20.9  69.6   280    3    2   6.3   3.4   27.6  81.6    -3.4     92  0.5
  6750   21.3  70.3   265    4    2   2.5   1.4   27.2  81.0    -3.7     74  0.4
  6500   21.1  70.0   260    6    3  -6.2  -3.4   26.3  79.4    -4.7     72  0.4
  6250   20.5  68.9   255    7    4  -4.0  -2.2   25.1  77.1    -5.9     81  0.4
  6000   20.4  68.7   250    9    5   1.6   0.9   24.3  75.8    -6.8     76  0.4
  5750   20.5  68.9   250    6    3   2.0   1.1   23.7  74.7    -7.5     67  0.3
  5500   20.6  69.1   250    3    2   0.5   0.3   23.1  73.6    -8.1     57  0.3

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

           08/14/2014 at 0900 MDT          |       08/14/2014 at 1200 MDT
                                           |
K index... +29.7  LI... -2.0               | K index... +29.1  LI... -2.6
CAPE... +164.0  CIN... -209.0              | CAPE... +541.9  CIN... -43.8
                                           |
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 -66.3 -87.3  285  20 10   1.7   1.0 | -66.1 -87.0  280  22 11   1.7   1.0
 45000 -61.5 -78.7  280  28 14   6.1   3.4 | -61.2 -78.2  280  31 16   6.2   3.4
 40000 -51.5 -60.7  255  27 14   7.6   4.2 | -51.0 -59.8  265  26 13   7.7   4.2
 38000 -47.0 -52.6  245  21 11   7.6   4.1 | -46.4 -51.5  255  22 11   7.7   4.2
 36000 -42.4 -44.3  225  17  9   8.2   4.5 | -41.8 -43.2  240  19 10   8.0   4.4
 34000 -37.0 -34.6  230  17  9   9.0   4.9 | -36.8 -34.2  230  18  9   8.3   4.6
 32000 -31.6 -24.9  235  16  8  10.0   5.5 | -31.9 -25.4  215  18  9   9.0   4.9
 30000 -26.9 -16.4  235  15  8   7.9   4.4 | -27.0 -16.6  215  17  9   8.1   4.5
 29000 -23.9 -11.0  235  15  7   8.0   4.4 | -24.0 -11.2  215  16  8   8.2   4.5
 28000 -21.7  -7.1  235  14  7   6.8   3.7 | -21.7  -7.1  220  16  8   6.6   3.6
 27000 -19.6  -3.3  230  13  7   6.9   3.8 | -19.7  -3.5  220  16  8   6.8   3.7
 26000 -17.6   0.3  230  13  7   6.9   3.8 | -17.7   0.1  220  16  8   6.8   3.7
 25000 -15.6   3.9  225  12  6   6.5   3.6 | -15.7   3.7  220  16  8   6.7   3.7
 24000 -13.8   7.2  220  12  6   6.0   3.3 | -13.8   7.2  220  16  8   6.6   3.6
 23000 -12.1  10.2  215  13  6   6.0   3.3 | -11.9  10.6  225  16  8   6.6   3.6
 22000 -10.4  13.3  210  13  7   5.8   3.2 | -10.0  14.0  225  16  8   6.3   3.5
 21000  -8.7  16.3  210  13  7   5.7   3.1 |  -8.2  17.2  225  15  8   6.0   3.3
 20000  -7.1  19.2  205  14  7   5.7   3.1 |  -6.5  20.3  225  15  8   6.0   3.3
 19500  -6.2  20.8  205  14  7   5.7   3.1 |  -5.6  21.9  225  14  7   6.1   3.3
 19000  -5.4  22.3  205  14  7   6.0   3.3 |  -4.8  23.4  225  14  7   5.7   3.1
 18500  -4.5  23.9  205  14  7   6.0   3.3 |  -3.9  25.0  225  14  7   5.8   3.2
 18000  -3.7  25.3  210  15  8   6.1   3.3 |  -3.1  26.4  225  14  7   5.8   3.2
 17500  -2.8  27.0  210  14  7   6.1   3.4 |  -2.3  27.9  225  14  7   5.8   3.2
 17000  -2.0  28.4  210  14  7   6.1   3.4 |  -1.5  29.3  225  14  7   5.8   3.2
 16500  -1.1  30.0  210  13  7   6.4   3.5 |  -0.6  30.9  220  14  7   5.9   3.2
 16000  -0.1  31.8  215  13  7   6.3   3.5 |   0.2  32.4  220  13  7   5.9   3.2
 15500   0.8  33.4  215  12  6   7.4   4.1 |   1.1  34.0  215  13  7   6.6   3.6
 15000   2.0  35.6  215  12  6   8.0   4.4 |   2.1  35.8  215  13  7   7.0   3.8
 14500   3.8  38.8  210  11  6   9.0   4.9 |   3.6  38.5  205  12  6   8.2   4.5
 14000   5.1  41.2  210  10  5   9.1   5.0 |   4.9  40.8  205  11  6   8.4   4.6
 13500   6.5  43.7  210  10  5   8.9   4.9 |   6.1  43.0  200  10  5   8.8   4.8
 13000   7.7  45.9  210  10  5   8.7   4.8 |   7.4  45.3  205  10  5   9.1   5.0
 12500   9.0  48.2  210   9  5   8.8   4.8 |   8.8  47.8  210   9  5   8.7   4.8
 12000  10.4  50.7  210   9  5   9.0   4.9 |  10.0  50.0  215   8  4   8.1   4.4
 11500  11.7  53.1  210   9  5   8.8   4.8 |  11.2  52.2  225   7  4   7.7   4.2
 11000  12.9  55.2  215   8  4   8.0   4.4 |  12.2  54.0  240   6  3   6.2   3.4
 10500  14.2  57.6  215   8  4   4.5   2.5 |  13.1  55.6  265   4  2   4.0   2.2
 10250  14.3  57.7  215   7  4   4.8   2.6 |  13.3  55.9  270   4  2   4.8   2.7
 10000  14.9  58.8  215   7  3   9.6   5.3 |  13.8  56.8  285   4  2   8.6   4.7
  9750  15.6  60.1  215   6  3   8.6   4.7 |  14.3  57.7  295   4  2   7.8   4.3
  9500  16.2  61.2  215   5  3   7.9   4.3 |  14.9  58.8  310   4  2   7.2   3.9
  9250  16.6  61.9  210   4  2   6.1   3.4 |  15.3  59.5  320   4  2   6.2   3.4
  9000  17.1  62.8  210   3  2   6.4   3.5 |  15.8  60.4  330   4  2   7.3   4.0
  8750  17.5  63.5  205   2  1   7.1   3.9 |  16.3  61.3  340   4  2   7.7   4.2
  8500  18.0  64.4  185   1  1   6.0   3.3 |  16.9  62.4  350   5  2   8.0   4.4
  8250  18.3  64.9  150   1  0   4.7   2.6 |  17.4  63.3  350   5  2   8.5   4.7
  8000  18.6  65.5  085   1  0   4.0   2.2 |  18.0  64.4  355   4  2   8.7   4.7
  7750  18.9  66.0  055   1  1   3.7   2.0 |  18.6  65.5  355   4  2   8.5   4.6
  7500  19.1  66.4  045   2  1   3.0   1.6 |  19.2  66.6  355   4  2   9.3   5.1
  7250  19.2  66.6  035   2  1   2.2   1.2 |  19.9  67.8  355   4  2  10.1   5.5
  7000  19.4  66.9  030   3  2   2.4   1.3 |  20.7  69.3  355   4  2   9.9   5.4
  6750  19.6  67.3  025   4  2   2.5   1.4 |  21.4  70.5  355   4  2  10.1   5.6
  6500  19.7  67.5  025   4  2   3.3   1.8 |  22.2  72.0  355   4  2  10.7   5.9
  6250  20.0  68.0  015   4  2   4.1   2.3 |  23.0  73.4  355   4  2  11.5   6.3
  6000  20.2  68.4  005   3  2   2.8   1.5 |  23.8  74.8  355   4  2  10.0   5.5
  5750  20.3  68.5  350   3  1   6.8   3.7 |  24.6  76.3  350   4  2  14.0   7.7
  5500  21.1  70.0  340   3  1  17.7   9.7 |  26.1  79.0  350   4  2  26.0  14.3

           08/14/2014 at 1500 MDT          |       08/14/2014 at 1800 MDT
                                           |
K index... +30.7  LI... -2.9               | K index... +26.5  LI... +0.1
CAPE... +366.8  CIN... -4.4                | CAPE... +3.5  CIN... -8.1
                                           |
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 -65.8 -86.4  280  16  8   1.3   0.7 | -66.4 -87.5  260  13  7   0.7   0.4
 45000 -61.2 -78.2  270  23 12   5.9   3.2 | -62.1 -79.8  245  19 10   6.3   3.5
 40000 -51.5 -60.7  265  23 12   9.1   5.0 | -51.8 -61.2  230  16  8   9.5   5.2
 38000 -46.0 -50.8  265  21 11   9.1   5.0 | -46.1 -51.0  235  15  8   9.5   5.2
 36000 -40.6 -41.1  260  20 10   8.8   4.8 | -40.4 -40.7  245  15  8   8.9   4.9
 34000 -35.4 -31.7  255  19 10   8.6   4.7 | -35.4 -31.7  250  14  7   8.4   4.6
 32000 -30.3 -22.5  245  19 10   9.7   5.3 | -30.3 -22.5  255  13  7   9.6   5.2
 30000 -25.3 -13.5  240  18  9   7.4   4.1 | -25.2 -13.4  260  13  7   7.7   4.2
 29000 -23.1  -9.6  235  17  9   7.4   4.1 | -22.9  -9.2  265  13  7   7.7   4.2
 28000 -21.0  -5.8  230  17  9   6.7   3.7 | -20.7  -5.3  265  13  7   6.6   3.6
 27000 -19.0  -2.2  230  17  9   6.8   3.7 | -18.8  -1.8  270  13  7   6.7   3.7
 26000 -17.0   1.4  230  18  9   6.8   3.7 | -16.8   1.8  275  13  7   6.8   3.7
 25000 -15.0   5.0  230  18  9   6.4   3.5 | -14.8   5.4  275  13  7   6.4   3.5
 24000 -13.3   8.1  225  17  9   5.9   3.2 | -13.0   8.6  280  14  7   6.0   3.3
 23000 -11.5  11.3  225  17  9   5.9   3.2 | -11.3  11.7  285  14  7   6.0   3.3
 22000  -9.8  14.4  225  17  9   5.6   3.1 |  -9.5  14.9  290  15  8   5.9   3.3
 21000  -8.3  17.1  225  16  8   5.2   2.9 |  -7.9  17.8  290  15  8   5.8   3.2
 20000  -6.8  19.8  225  15  8   5.2   2.9 |  -6.2  20.8  290  15  8   5.8   3.2
 19500  -6.0  21.2  225  15  8   5.3   2.9 |  -5.4  22.3  290  15  8   5.9   3.2
 19000  -5.3  22.5  225  15  7   5.1   2.8 |  -4.6  23.7  290  15  8   5.3   2.9
 18500  -4.5  23.9  225  14  7   5.1   2.8 |  -3.8  25.2  290  15  8   5.3   2.9
 18000  -3.8  25.2  230  13  7   5.3   2.9 |  -3.0  26.6  290  15  8   5.2   2.9
 17500  -3.0  26.6  230  13  7   5.6   3.1 |  -2.3  27.9  290  15  8   5.0   2.8
 17000  -2.2  28.0  235  12  6   5.6   3.1 |  -1.6  29.1  285  14  7   4.9   2.7
 16500  -1.4  29.5  235  12  6   6.0   3.3 |  -0.8  30.6  285  14  7   6.4   3.5
 16000  -0.5  31.1  235  11  6   6.0   3.3 |   0.1  32.2  285  13  7   6.4   3.5
 15500   0.4  32.7  235  11  6   6.6   3.6 |   1.0  33.8  285  13  7   6.3   3.5
 15000   1.9  35.4  235  10  5   7.1   3.9 |   2.4  36.3  280  12  6   6.3   3.4
 14500   2.9  37.2  235   9  5   7.4   4.0 |   3.4  38.1  280  12  6   6.6   3.6
 14000   4.0  39.2  240   8  4   7.4   4.1 |   4.4  39.9  275  12  6   6.7   3.7
 13500   5.1  41.2  245   8  4   7.3   4.0 |   5.3  41.5  275  12  6   6.6   3.6
 13000   6.1  43.0  265   6  3   7.2   4.0 |   6.3  43.3  275  11  6   6.5   3.6
 12500   7.1  44.8  290   6  3   7.8   4.3 |   7.3  45.1  275  11  6   6.6   3.6
 12000   8.3  46.9  300   6  3   8.7   4.8 |   8.2  46.8  280  11  6   6.9   3.8
 11500   9.6  49.3  310   6  3   9.0   4.9 |   9.3  48.7  280  11  6   6.9   3.8
 11000  10.9  51.6  315   6  3   9.6   5.3 |  10.3  50.5  285  11  6   6.8   3.7
 10500  12.2  54.0  315   6  3   5.9   3.2 |  11.3  52.3  290  11  6   3.5   1.9
 10250  12.5  54.5  315   6  3   7.2   3.9 |  11.5  52.7  290  11  6   4.4   2.4
 10000  13.4  56.1  315   7  3  13.1   7.2 |  12.1  53.8  290  12  6   9.6   5.2
  9750  14.3  57.7  315   7  3  12.0   6.6 |  12.7  54.9  295  12  6   8.4   4.6
  9500  15.1  59.2  315   7  3  10.3   5.7 |  13.3  55.9  295  12  6   7.9   4.3
  9250  15.8  60.4  315   7  3   8.3   4.5 |  13.8  56.8  300  13  6   6.6   3.6
  9000  16.5  61.7  315   7  4  10.2   5.6 |  14.3  57.7  300  13  7   7.8   4.3
  8750  17.3  63.1  315   7  4  11.0   6.0 |  14.9  58.8  300  14  7   8.7   4.8
  8500  18.1  64.6  315   7  4  10.6   5.8 |  15.5  59.9  300  14  7   8.2   4.5
  8250  18.8  65.8  315   7  4  10.5   5.8 |  16.1  61.0  305  14  7   7.9   4.3
  8000  19.6  67.3  315   7  4  10.1   5.5 |  16.7  62.1  305  15  8   7.8   4.3
  7750  20.3  68.5  315   7  4   9.6   5.3 |  17.2  63.0  305  15  8   7.8   4.3
  7500  21.1  70.0  315   7  4  10.1   5.5 |  17.8  64.0  310  15  8   7.7   4.2
  7250  21.8  71.2  315   7  4  10.6   5.8 |  18.3  64.9  310  15  8   7.6   4.2
  7000  22.6  72.7  315   7  4  10.0   5.5 |  18.9  66.0  315  15  8   7.7   4.2
  6750  23.3  73.9  315   8  4   9.1   5.0 |  19.4  66.9  315  15  8   7.7   4.2
  6500  24.0  75.2  315   8  4  10.0   5.5 |  19.9  67.8  315  14  7   6.8   3.7
  6250  24.8  76.6  315   8  4  11.3   6.2 |  20.4  68.7  315  13  7   6.8   3.7
  6000  25.6  78.1  315   8  4   9.6   5.2 |  20.8  69.4  315  11  6   5.4   3.0
  5750  26.4  79.5  315   8  4  13.3   7.3 |  21.1  70.0  310  10  5   6.8   3.7
  5500  27.8  82.0  315   8  4  25.4  13.9 |  21.8  71.2  305   8  4  14.6   8.0
________________________________________________________________________________

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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