Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191316
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0715 MDT Tuesday, August 19, 2014

This forecast is for Tuesday, August 19, 2014:

If the trigger temperature of 83.0 F/28.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 544 ft/min (2.8 m/s)
   Maximum height of thermals.................. 15549 ft MSL (10264 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1330 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8760 ft MSL (3475 ft AGL)
Thermal soaring outlook for Wednesday 08/20.... Fair

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)................ Weak PVA
Potential height of wave....................... 14377 ft MSL (9092 ft AGL)
Wave soaring outlook for Wednesday 08/20....... Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 06:15:19 / 19:51:20 MDT
Total possible sunshine........... 13 hr 36 min 1 sec (816 min 1 sec)
Altitude of sun at 13:02:57 MDT... 62.83 degrees

Upper air data from rawinsonde observation taken on 08/19/2014 at 0600 MDT

Freezing level.................. 15690 ft MSL (10405 ft AGL)
Convective condensation level... 16677 ft MSL (11392 ft AGL)
Lifted condensation level....... 16581 ft MSL (11296 ft AGL)
Lifted index.................... -1.5
K index......................... +22.4

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  -65.3 -85.5   285   35   18   4.2   2.3   84.6 184.3    31.1      M    M
 45000  -60.4 -76.7   290   44   23   3.3   1.8   68.6 155.5    23.4      M    M
 40000  -56.1 -69.0   260   52   27 -11.0  -6.1   51.6 124.9    13.7      M    M
 38000  -52.7 -62.9   265   48   25   8.0   4.4   47.9 118.3    11.6      M    M
 36000  -47.5 -53.5   275   45   23   8.7   4.8   47.0 116.7    11.2      M    M
 34000  -42.3 -44.1   265   40   21   8.6   4.7   45.8 114.5    10.6      M    M
 32000  -37.2 -35.0   255   36   19   8.6   4.7   45.1 113.2    10.3      M    M
 30000  -32.3 -26.1   265   31   16   8.1   4.4   44.0 111.2     9.7      M    M
 29000  -29.8 -21.6   265   30   15   8.1   4.4   43.3 110.0     9.3      M    M
 28000  -26.6 -15.9   265   28   14   8.7   4.8   42.8 109.0     9.0      M    M
 27000  -24.0 -11.2   270   26   13   8.8   4.8   42.4 108.2     8.8      M    M
 26000  -21.2  -6.2   270   24   12   9.5   5.2   42.2 107.9     8.8      M    M
 25000  -18.9  -2.0   280   22   11   2.3   1.2   41.5 106.7     8.4      M    M
 24000  -17.7   0.1   305   21   11   4.1   2.2   39.3 102.7     6.7      M    M
 23000  -16.5   2.3   285   20   10   3.9   2.1   37.3  99.1     5.0      M    M
 22000  -14.7   5.5   285   21   11   4.6   2.5   35.9  96.6     3.9      M    M
 21000  -13.2   8.2   300   20   10   8.3   4.6   34.4  94.0     2.6      M    M
 20000  -10.7  12.7   320   20   10   8.7   4.8   33.9  93.0     2.1      M    M
 19500   -9.6  14.7   310   18    9   6.6   3.6   33.5  92.3     1.8      M    M
 19000   -8.4  16.9   305   16    8   6.5   3.5   33.3  91.9     1.6      M    M
 18500   -7.6  18.3   305   15    8   9.0   4.9   32.5  90.6     0.8      M    M
 18000   -6.3  20.7   310   13    7   9.2   5.0   32.4  90.4     0.7      M    M
 17500   -4.9  23.2   310   12    6   9.2   5.1   32.4  90.2     0.6      M    M
 17000   -3.6  25.5   315   10    5   9.3   5.1   32.3  90.1     0.5      M    M
 16500   -2.3  27.9   305    8    4   7.9   4.4   32.2  89.9     0.4      M    M
 16000   -1.2  29.8   280    6    3   9.2   5.0   31.9  89.4     0.1      M    M
 15500    0.2  32.4   270    7    3   9.5   5.2   31.8  89.3     0.0      M    M
 15000    1.7  35.1   265    7    4   9.6   5.2   31.8  89.2    -0.0    893  4.5
 14500    3.1  37.6   265    8    4   9.6   5.3   31.8  89.2    -0.1    836  4.2
 14000    5.2  41.4   260    9    5   9.5   5.2   31.8  89.2    -0.1    750  3.8
 13500    6.6  43.9   255   10    5   8.9   4.9   31.7  89.1    -0.1    692  3.5
 13000    7.8  46.0   250   11    6   7.7   4.2   31.4  88.6    -0.4    643  3.3
 12500    8.9  48.0   230   11    6   7.7   4.2   31.1  88.0    -0.7    594  3.0
 12000   10.1  50.2   215   12    6   7.7   4.2   30.8  87.5    -1.1    546  2.8
 11500   11.2  52.2   215   13    7   7.7   4.2   30.4  86.8    -1.4    497  2.5
 11000   12.3  54.1   220   14    7   7.7   4.2   30.1  86.2    -1.8    449  2.3
 10500   13.4  56.1   220   16    8   7.8   4.3   29.8  85.7    -2.1    400  2.0
 10250   14.0  57.2   220   16    8   8.1   4.5   29.7  85.4    -2.2    375  1.9
 10000   14.6  58.3   220   16    8   8.4   4.6   29.5  85.2    -2.4    349  1.8
  9750   15.3  59.5   220   16    8   8.3   4.6   29.4  85.0    -2.5    323  1.6
  9500   15.9  60.6   220   16    8   8.3   4.6   29.3  84.8    -2.6    297  1.5
  9250   16.5  61.7   220   16    8   8.3   4.6   29.2  84.6    -2.7    271  1.4
  9000   17.1  62.8   220   16    8   8.3   4.5   29.1  84.4    -2.8    245  1.2
  8750   17.6  63.7   215   16    8   4.6   2.5   28.9  84.0    -3.0    223  1.1
  8500   17.8  64.0   210   15    8   1.9   1.1   28.3  83.0    -3.6    211  1.1
  8250   17.9  64.2   205   15    8   2.7   1.5   27.8  82.0    -4.2    199  1.0
  8000   18.1  64.6   200   15    8   2.5   1.4   27.2  81.0    -4.8    187  1.0
  7750   18.2  64.8   195   16    8   2.6   1.4   26.7  80.0    -5.4    176  0.9
  7500   18.4  65.1   190   16    8   2.5   1.4   26.1  79.0    -6.0    164  0.8
  7250   18.5  65.3   190   17    9   2.8   1.5   25.6  78.0    -6.6    152  0.8
  7000   18.7  65.7   185   18    9   4.2   2.3   25.1  77.1    -7.1    138  0.7
  6750   19.1  66.4   190   17    9   4.6   2.5   24.7  76.4    -7.5    119  0.6
  6500   19.5  67.1   200   16    8   5.7   3.1   24.3  75.7    -7.9    101  0.5
  6250   19.9  67.8   205   15    8   0.9   0.5   23.9  75.1    -8.2     82  0.4
  6000   19.5  67.1   215   14    7  -8.4  -4.6   22.9  73.1    -9.4     86  0.4
  5750   18.7  65.7   215   10    5 -12.0  -6.6   21.3  70.4   -11.1    104  0.5
  5500   17.5  63.5   215    5    2 -17.4  -9.6   19.5  67.2   -12.8    130  0.7

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

           08/19/2014 at 0900 MDT          |       08/19/2014 at 1200 MDT
                                           |
K index... +28.1  LI... -2.4               | K index... +21.6  LI... -3.1
CAPE... +414.9  CIN... -17.2               | CAPE... +640.6  CIN... -123.9
                                           |
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 -63.5 -82.3  280  22 11  -0.1  -0.1 | -63.7 -82.7  270  20 10   0.1   0.1
 45000 -61.0 -77.8  280  37 19   6.0   3.3 | -60.8 -77.4  275  34 18   6.2   3.4
 40000 -52.3 -62.1  285  46 24   4.3   2.4 | -51.8 -61.2  280  50 26   4.3   2.4
 38000 -49.7 -57.5  280  41 21   4.3   2.4 | -49.2 -56.6  275  42 22   4.3   2.4
 36000 -47.1 -52.8  270  37 19   4.1   2.3 | -46.6 -51.9  265  35 18   4.2   2.3
 34000 -42.2 -44.0  265  36 19   9.1   5.0 | -41.9 -43.4  260  33 17   8.8   4.8
 32000 -36.7 -34.1  255  38 19   9.2   5.0 | -36.6 -33.9  255  31 16   8.8   4.8
 30000 -30.8 -23.4  250  33 17   8.7   4.8 | -31.0 -23.8  255  29 15   8.2   4.5
 29000 -28.2 -18.8  250  30 15   8.8   4.8 | -28.6 -19.5  250  28 15   8.2   4.5
 28000 -25.7 -14.3  250  27 14   6.7   3.7 | -26.2 -15.2  250  28 14   7.3   4.0
 27000 -24.0 -11.2  250  22 11   5.6   3.1 | -24.2 -11.6  245  27 14   6.8   3.7
 26000 -22.3  -8.1  250  16  8   5.6   3.1 | -22.2  -8.0  245  26 14   6.8   3.7
 25000 -20.6  -5.1  255  11  6   5.7   3.1 | -20.2  -4.4  240  26 13   6.8   3.8
 24000 -19.1  -2.4  250   9  5   5.0   2.7 | -18.4  -1.1  230  23 12   5.8   3.2
 23000 -17.6   0.3  245   7  4   5.0   2.7 | -16.7   1.9  220  20 10   5.9   3.2
 22000 -16.1   3.0  235   5  3   5.7   3.1 | -15.0   5.0  200  18  9   6.1   3.4
 21000 -13.6   7.5  240   6  3   9.1   5.0 | -12.7   9.1  195  16  8   7.8   4.3
 20000 -10.9  12.4  245   7  3   9.1   5.0 | -10.4  13.3  195  13  7   7.8   4.3
 19500  -9.5  14.9  245   7  4   9.1   5.0 |  -9.3  15.3  190  12  6   7.9   4.3
 19000  -8.2  17.2  250   8  4   9.5   5.2 |  -8.2  17.2  190  11  5   6.6   3.6
 18500  -6.8  19.8  245   8  4   9.5   5.2 |  -7.2  19.0  185  10  5   6.5   3.6
 18000  -5.4  22.3  245   8  4   9.4   5.1 |  -6.3  20.7  180   9  5   7.1   3.9
 17500  -4.1  24.6  245   8  4   8.9   4.9 |  -5.0  23.0  175   8  4   9.5   5.2
 17000  -2.8  27.0  245   9  4   8.9   4.9 |  -3.6  25.5  175   8  4   9.4   5.1
 16500  -1.5  29.3  240   9  4   9.4   5.1 |  -2.1  28.2  180   7  4   9.8   5.4
 16000  -0.2  31.6  240   9  4   9.4   5.2 |  -0.7  30.7  185   7  3   9.8   5.4
 15500   1.2  34.2  240   9  5   9.1   5.0 |   0.8  33.4  190   6  3   9.7   5.3
 15000   3.1  37.6  235  10  5   8.8   4.8 |   2.9  37.2  195   7  3   9.6   5.2
 14500   4.4  39.9  235  10  5   8.7   4.8 |   4.3  39.7  200   7  4   9.5   5.2
 14000   5.7  42.3  230  10  5   8.6   4.7 |   5.7  42.3  205   7  4   9.5   5.2
 13500   6.9  44.4  225  11  6   8.7   4.8 |   7.1  44.8  205   8  4   9.4   5.1
 13000   8.2  46.8  225  11  6   8.7   4.8 |   8.4  47.1  205   8  4   9.3   5.1
 12500   9.4  48.9  220  11  6   8.7   4.8 |   9.7  49.5  205   8  4   9.0   5.0
 12000  10.7  51.3  220  11  5   8.8   4.8 |  10.9  51.6  205   8  4   8.1   4.4
 11500  12.0  53.6  220  10  5   8.6   4.7 |  12.1  53.8  210   7  4   8.0   4.4
 11000  13.2  55.8  215  10  5   7.6   4.2 |  13.0  55.4  210   6  3   6.3   3.4
 10500  14.3  57.7  215  10  5   5.0   2.7 |  14.0  57.2  220   5  3   8.4   4.6
 10250  14.6  58.3  215   9  5   5.1   2.8 |  14.7  58.5  230   4  2   8.5   4.7
 10000  15.2  59.4  215   9  5   8.6   4.7 |  15.2  59.4  245   4  2   5.9   3.2
  9750  15.8  60.4  215   9  4   7.8   4.3 |  15.7  60.3  260   4  2   6.7   3.7
  9500  16.4  61.5  215   8  4   7.5   4.1 |  16.1  61.0  275   4  2   6.0   3.3
  9250  16.9  62.4  215   8  4   6.0   3.3 |  16.6  61.9  290   4  2   5.6   3.1
  9000  17.3  63.1  210   7  4   6.2   3.4 |  17.1  62.8  300   5  2   6.8   3.8
  8750  17.8  64.0  210   7  4   6.8   3.8 |  17.6  63.7  310   6  3   7.6   4.2
  8500  18.3  64.9  205   7  3   6.5   3.6 |  18.2  64.8  315   6  3   7.3   4.0
  8250  18.7  65.7  200   6  3   6.5   3.6 |  18.7  65.7  320   7  4   7.7   4.2
  8000  19.2  66.6  200   6  3   5.4   3.0 |  19.3  66.7  320   8  4   6.5   3.6
  7750  19.5  67.1  195   6  3   4.7   2.6 |  19.6  67.3  325   8  4   5.1   2.8
  7500  19.8  67.6  195   6  3   3.8   2.1 |  20.0  68.0  325   8  4   6.2   3.4
  7250  20.0  68.0  200   6  3   2.4   1.3 |  20.4  68.7  330   6  3   7.2   4.0
  7000  20.1  68.2  210   5  2   1.9   1.1 |  20.8  69.4  335   5  2   7.8   4.3
  6750  20.2  68.4  220   4  2   0.6   0.3 |  21.3  70.3  345   4  2   8.1   4.4
  6500  20.2  68.4  230   3  2  -0.3  -0.1 |  21.9  71.4  355   3  1   9.7   5.3
  6250  20.1  68.2  225   2  1   0.2   0.1 |  22.7  72.9  355   3  1  11.3   6.2
  6000  20.0  68.0  215   2  1  -1.3  -0.7 |  23.5  74.3  355   2  1  10.2   5.6
  5750  19.8  67.6  185   1  1   0.9   0.5 |  24.3  75.7  360   2  1  13.0   7.1
  5500  20.1  68.2  180   1  1  11.9   6.5 |  25.5  77.9  005   3  1  21.8  12.0

           08/19/2014 at 1500 MDT          |       08/19/2014 at 1800 MDT
                                           |
K index... +25.7  LI... -2.2               | K index... +29.0  LI... -1.3
CAPE... +214.5  CIN... -20.9               | CAPE... +39.5  CIN... -36.9
                                           |
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 -63.9 -83.0  285  27 14   1.2   0.6 | -64.0 -83.2  285  29 15   0.8   0.5
 45000 -60.3 -76.5  290  45 23   4.9   2.7 | -61.2 -78.2  285  48 24   4.0   2.2
 40000 -52.8 -63.0  285  57 29   6.2   3.4 | -54.6 -66.3  280  59 30   8.1   4.4
 38000 -49.0 -56.2  280  52 27   6.3   3.5 | -49.7 -57.5  280  46 24   8.2   4.5
 36000 -45.2 -49.4  275  46 24   6.2   3.4 | -44.7 -48.5  270  35 18   8.1   4.5
 34000 -40.5 -40.9  265  41 21   8.3   4.5 | -39.5 -39.1  270  32 16   8.9   4.9
 32000 -35.5 -31.9  255  37 19   8.3   4.6 | -34.1 -29.4  265  31 16   8.7   4.8
 30000 -29.9 -21.8  245  32 17   8.3   4.6 | -28.7 -19.7  260  29 15   8.0   4.4
 29000 -27.5 -17.5  245  30 16   8.3   4.6 | -26.3 -15.3  255  28 14   8.0   4.4
 28000 -25.0 -13.0  240  28 15   7.6   4.2 | -24.0 -11.2  255  27 14   7.2   4.0
 27000 -22.9  -9.2  240  28 14   7.3   4.0 | -22.0  -7.6  250  26 13   6.8   3.7
 26000 -20.7  -5.3  240  28 14   7.3   4.0 | -20.0  -4.0  245  26 13   6.8   3.8
 25000 -18.6  -1.5  240  28 14   7.3   4.0 | -17.9  -0.2  240  25 13   6.9   3.8
 24000 -16.7   1.9  240  26 14   6.1   3.3 | -16.0   3.2  240  26 14   6.5   3.5
 23000 -15.0   5.0  235  25 13   6.1   3.3 | -14.1   6.6  235  28 14   6.5   3.6
 22000 -13.2   8.2  230  24 12   6.1   3.3 | -12.2  10.0  235  29 15   6.5   3.6
 21000 -11.4  11.5  220  22 11   6.2   3.4 | -10.6  12.9  230  30 15   5.5   3.0
 20000  -9.6  14.7  210  19 10   6.2   3.4 |  -9.0  15.8  220  30 15   5.5   3.0
 19500  -8.7  16.3  205  19 10   6.2   3.4 |  -8.2  17.2  220  30 16   5.5   3.0
 19000  -7.8  18.0  200  18  9   6.5   3.6 |  -7.4  18.7  215  30 16   6.1   3.3
 18500  -6.8  19.8  200  16  8   6.6   3.6 |  -6.5  20.3  215  28 15   6.3   3.4
 18000  -5.8  21.6  200  15  8   6.7   3.7 |  -5.5  22.1  210  26 13   6.3   3.5
 17500  -4.8  23.4  200  14  7   7.6   4.2 |  -4.5  23.9  205  24 12   7.7   4.2
 17000  -3.7  25.3  200  12  6   7.6   4.2 |  -3.4  25.9  200  21 11   7.6   4.2
 16500  -2.5  27.5  200  11  6   8.0   4.4 |  -2.3  27.9  190  19 10   7.6   4.2
 16000  -1.3  29.7  200  11  5   8.1   4.4 |  -1.2  29.8  185  18  9   7.7   4.2
 15500  -0.2  31.6  205  10  5   8.1   4.4 |  -0.1  31.8  175  17  9   7.7   4.2
 15000   1.6  34.9  205  10  5   8.1   4.4 |   1.6  34.9  165  15  8   8.0   4.4
 14500   2.8  37.0  205  10  5   8.7   4.8 |   2.8  37.0  160  14  7   8.7   4.8
 14000   4.1  39.4  205  11  6   9.0   5.0 |   4.1  39.4  160  13  7   9.3   5.1
 13500   5.5  41.9  205  11  6   9.4   5.2 |   5.5  41.9  155  12  6   9.5   5.2
 13000   7.0  44.6  205  11  6  10.0   5.5 |   7.0  44.6  155  11  6  10.0   5.5
 12500   8.5  47.3  205  11  6   9.9   5.5 |   8.4  47.1  155  11  6   9.9   5.5
 12000   9.9  49.8  205  10  5   9.5   5.2 |   9.9  49.8  155  11  5   9.2   5.1
 11500  11.3  52.3  205   9  5   9.4   5.2 |  11.3  52.3  155  10  5   9.3   5.1
 11000  12.5  54.5  205   8  4   7.4   4.1 |  12.6  54.7  160   9  5   8.5   4.7
 10500  13.7  56.7  205   6  3  10.1   5.5 |  13.8  56.8  160   7  4  10.5   5.8
 10250  14.5  58.1  200   5  2  10.9   6.0 |  14.7  58.5  160   6  3  10.7   5.9
 10000  15.1  59.2  200   4  2   7.9   4.4 |  15.4  59.7  160   5  3   8.3   4.6
  9750  15.7  60.3  195   3  2   8.8   4.9 |  16.0  60.8  160   5  2   8.9   4.9
  9500  16.3  61.3  185   2  1   8.4   4.6 |  16.7  62.1  155   4  2   8.9   4.9
  9250  16.9  62.4  175   2  1   8.7   4.8 |  17.3  63.1  155   3  1   8.0   4.4
  9000  17.5  63.5  170   2  1   9.8   5.4 |  17.9  64.2  160   2  1   7.4   4.1
  8750  18.3  64.9  170   2  1  10.0   5.5 |  18.5  65.3  170   1  0   8.0   4.4
  8500  19.0  66.2  170   2  1  10.1   5.5 |  19.0  66.2  310   1  0   7.7   4.2
  8250  19.7  67.5  170   1  1  10.9   6.0 |  19.7  67.5  320   2  1   9.4   5.2
  8000  20.5  68.9  170   1  1  10.3   5.7 |  20.4  68.7  320   3  1   9.5   5.2
  7750  21.3  70.3  170   1  1   9.4   5.1 |  21.0  69.8  315   4  2   8.2   4.5
  7500  22.0  71.6  170   1  1   9.8   5.4 |  21.7  71.1  315   4  2   8.9   4.9
  7250  22.7  72.9  170   1  1  10.2   5.6 |  22.3  72.1  315   5  3  10.2   5.6
  7000  23.5  74.3  170   1  1  10.0   5.5 |  23.1  73.6  315   5  3  10.5   5.8
  6750  24.2  75.6  175   1  0   8.8   4.9 |  23.9  75.0  315   6  3   9.5   5.2
  6500  24.9  76.8  185   1  0   9.9   5.4 |  24.6  76.3  315   6  3   9.5   5.2
  6250  25.7  78.3  185   1  0  11.5   6.3 |  25.3  77.5  315   6  3   9.8   5.4
  6000  26.5  79.7  185   1  0  10.8   5.9 |  26.0  78.8  315   6  3   9.9   5.4
  5750  27.3  81.1  190   1  0  11.8   6.5 |  26.8  80.2  315   6  3   9.8   5.4
  5500  28.4  83.1  200   1  0  19.0  10.4 |  27.5  81.5  315   6  3  11.2   6.1
________________________________________________________________________________

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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