Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151222
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0622 MDT Friday, September 15, 2017

This forecast is for Friday, September 15, 2017:

If the trigger temperature of 71.1 F/21.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 685 ft/min (3.5 m/s)
   Maximum height of thermals.................. 14237 ft MSL (8952 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ 1700 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13242 ft MSL (7957 ft AGL)
Thermal soaring outlook for Saturday 09/16..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 14134 ft MSL (8849 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 37239 ft MSL (31954 ft AGL)
Wave soaring outlook for Saturday 09/16........ Fair

Remarks...

Sunrise/Sunset.................... 06:41:06 / 19:07:59 MDT
Total possible sunshine........... 12 hr 26 min 53 sec (746 min 53 sec)
Altitude of sun at 12:54:32 MDT... 52.94 degrees

Upper air data from rawinsonde observation taken on 09/15/2017 at 0600 MDT

Freezing level.................. 14980 ft MSL (9695 ft AGL)
Convective condensation level... 16420 ft MSL (11135 ft AGL)
Lifted condensation level....... 15793 ft MSL (10508 ft AGL)
Lifted index.................... -0.8
K index......................... -3.4

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  -62.4 -80.3   255   38   19  -0.2  -0.1   90.7 195.3    36.2      M    M
 45000  -57.9 -72.2   205   36   19   6.2   3.4   73.7 164.7    28.2      M    M
 40000  -54.4 -65.9   230   61   32  -4.6  -2.5   55.6 132.1    18.2      M    M
 38000  -53.5 -64.3   220   68   35   7.3   4.0   48.2 118.7    13.6      M    M
 36000  -49.2 -56.6   220   67   35   6.9   3.8   46.0 114.7    12.4      M    M
 34000  -44.9 -48.8   220   61   31   7.5   4.1   43.6 110.5    11.0      M    M
 32000  -40.4 -40.7   225   58   30   7.5   4.1   41.8 107.2     9.9      M    M
 30000  -36.1 -33.0   230   51   27   7.0   3.8   40.0 104.0     8.8      M    M
 29000  -33.2 -27.8   225   48   24   8.7   4.8   38.9 102.1     8.1      M    M
 28000  -30.6 -23.1   215   45   23   8.7   4.8   38.5 101.3     7.9      M    M
 27000  -28.0 -18.4   210   44   22   8.7   4.8   38.2 100.8     7.8      M    M
 26000  -25.3 -13.5   200   43   22   8.7   4.8   38.0 100.4     7.7      M    M
 25000  -22.7  -8.9   210   43   22   8.7   4.8   37.5  99.6     7.4      M    M
 24000  -20.1  -4.2   215   42   22   8.8   4.8   37.1  98.8     7.1      M    M
 23000  -17.5   0.5   220   39   20   8.8   4.8   36.7  98.1     6.9      M    M
 22000  -15.0   5.0   220   37   19   6.5   3.6   36.2  97.2     6.6      M    M
 21000  -13.1   8.4   225   35   18   6.5   3.5   35.1  95.2     5.6      M    M
 20000  -11.2  11.8   230   33   17   6.5   3.5   34.0  93.2     4.7      M    M
 19500  -10.2  13.6   230   33   17   6.5   3.5   33.4  92.1     4.2      M    M
 19000   -9.3  15.3   225   32   17   6.5   3.6   32.8  91.0     3.7      M    M
 18500   -8.2  17.2   220   30   16   7.6   4.2   32.3  90.2     3.3      M    M
 18000   -7.1  19.2   215   28   14   7.5   4.1   31.9  89.5     3.0      M    M
 17500   -5.9  21.4   210   26   13   7.5   4.1   31.6  88.8     2.7      M    M
 17000   -4.8  23.4   200   24   12   7.5   4.1   31.2  88.2     2.5      M    M
 16500   -3.7  25.3   205   24   12   7.5   4.1   30.9  87.5     2.1      M    M
 16000   -2.6  27.3   210   24   12   7.5   4.1   30.5  86.9     1.8      M    M
 15500   -1.4  29.5   215   24   12   7.5   4.1   30.1  86.1     1.4      M    M
 15000   -0.3  31.5   220   23   12   7.5   4.1   29.7  85.4     1.1      M    M
 14500    1.2  34.2   225   23   12   2.6   1.4   28.9  84.0     0.4      M    M
 14000    1.2  34.2   230   23   12   0.8   0.4   27.4  81.3    -1.0    675  3.4
 13500    1.2  34.2   240   22   11   1.1   0.6   25.9  78.6    -2.5    660  3.4
 13000    1.2  34.2   245   21   11   3.2   1.8   24.5  76.1    -4.0    645  3.3
 12500    2.2  36.0   255   21   11   8.2   4.5   24.0  75.3    -4.5    602  3.1
 12000    3.3  37.9   260   21   11   8.1   4.4   23.8  74.8    -4.8    552  2.8
 11500    4.5  40.1   260   20   10   8.1   4.4   23.5  74.3    -5.2    502  2.5
 11000    5.7  42.3   265   19   10   8.1   4.4   23.2  73.8    -5.5    452  2.3
 10500    6.9  44.4   270   18    9   8.1   4.4   22.9  73.3    -5.8    402  2.0
 10250    7.4  45.3   270   17    9   8.2   4.5   22.8  73.1    -6.0    377  1.9
 10000    8.0  46.4   275   19   10   8.7   4.8   22.7  72.9    -6.1    352  1.8
  9750    8.7  47.7   270   17    9   8.9   4.9   22.7  72.8    -6.2    325  1.6
  9500    9.3  48.7   265   14    7   8.8   4.9   22.6  72.7    -6.3    298  1.5
  9250   10.0  50.0   260   13    6   8.9   4.9   22.5  72.6    -6.4    271  1.4
  9000   10.6  51.1   255   11    6   8.9   4.9   22.5  72.5    -6.4    244  1.2
  8750   11.3  52.3   255   10    5   8.9   4.9   22.4  72.4    -6.5    218  1.1
  8500   11.9  53.4   250    9    5   8.9   4.9   22.3  72.2    -6.6    191  1.0
  8250   12.6  54.7   250    9    4   8.9   4.9   22.3  72.1    -6.7    164  0.8
  8000   13.2  55.8   245    8    4   8.9   4.9   22.2  72.0    -6.8    137  0.7
  7750   13.9  57.0   245    8    4   8.9   4.9   22.2  71.9    -6.9    111  0.6
  7500   14.5  58.1   250    8    4   8.9   4.9   22.1  71.7    -7.0     84  0.4
  7250   15.2  59.4   250    9    5   8.8   4.8   22.0  71.6    -7.1     57  0.3
  7000   15.8  60.4   250    9    5   9.2   5.1   21.9  71.5    -7.2     30  0.2
  6750   16.4  61.5   260    8    4   7.8   4.3   21.9  71.4    -7.4      4  0.0
  6500   17.1  62.8   275    7    4  13.2   7.3   21.8  71.2    -7.5      M    M
  6250   17.7  63.9   290    7    4  -7.2  -3.9   21.7  71.1    -7.6      M    M
  6000   16.0  60.8   305    7    4 -13.6  -7.5   19.6  67.2   -10.1      M    M
  5750   16.0  60.8   295    5    2   9.4   5.2   18.9  66.1   -10.8      M    M
  5500   16.0  60.8   260    3    1 -16.7  -9.2   18.3  64.9   -11.6      M    M

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

           09/15/2017 at 0900 MDT          |       09/15/2017 at 1200 MDT
                                           |
CAPE...    +0.6    LI...       +1.9        | CAPE...     0.0    LI...       +3.0
CINH...   -26.5    K Index...  +6.6        | CINH...     0.0    K Index...  +9.1
                                           |
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 -59.8 -75.6  225  11  6   1.4   0.7 | -59.1 -74.4  220  12  6   1.6   0.9
 45000 -57.3 -71.1  215  19 10   2.3   1.3 | -56.5 -69.7  220  20 10   1.8   1.0
 40000 -53.9 -65.0  225  31 16   3.2   1.7 | -53.8 -64.8  225  31 16   2.4   1.3
 38000 -51.2 -60.2  225  31 16   4.5   2.5 | -51.4 -60.5  225  31 16   4.1   2.3
 36000 -48.4 -55.1  220  30 16   4.5   2.5 | -49.0 -56.2  220  32 16   4.1   2.3
 34000 -44.6 -48.3  220  30 15   8.0   4.4 | -45.2 -49.4  220  31 16   8.0   4.4
 32000 -39.8 -39.6  220  28 15   8.0   4.4 | -40.4 -40.7  225  29 15   8.0   4.4
 30000 -34.3 -29.7  220  27 14   8.2   4.5 | -35.0 -31.0  225  27 14   8.0   4.4
 29000 -31.9 -25.4  220  27 14   8.2   4.5 | -32.6 -26.7  230  27 14   8.0   4.4
 28000 -29.4 -20.9  220  26 13   8.3   4.5 | -30.2 -22.4  230  26 13   8.0   4.4
 27000 -27.1 -16.8  220  25 13   7.5   4.1 | -28.0 -18.4  230  25 13   7.1   3.9
 26000 -24.9 -12.8  220  24 12   7.5   4.1 | -25.9 -14.6  230  24 12   7.1   3.9
 25000 -22.7  -8.9  220  23 12   7.5   4.1 | -23.8 -10.8  230  23 12   7.1   3.9
 24000 -20.4  -4.7  220  22 11   8.0   4.4 | -21.6  -6.9  230  21 11   8.1   4.4
 23000 -18.0  -0.4  225  21 11   8.0   4.4 | -19.2  -2.6  225  20 10   8.1   4.4
 22000 -15.6   3.9  230  20 10   8.0   4.4 | -16.8   1.8  225  19 10   8.1   4.5
 21000 -13.3   8.1  230  19 10   7.4   4.1 | -14.3   6.3  225  18  9   8.4   4.6
 20000 -11.1  12.0  235  17  9   7.4   4.1 | -11.8  10.8  230  17  9   8.4   4.6
 19500 -10.0  14.0  235  17  9   7.4   4.1 | -10.5  13.1  235  17  9   8.4   4.6
 19000  -8.9  16.0  240  16  8   7.5   4.1 |  -9.3  15.3  240  17  9   8.4   4.6
 18500  -7.9  17.8  240  15  8   6.0   3.3 |  -8.1  17.4  240  16  8   7.1   3.9
 18000  -7.0  19.4  245  14  7   6.2   3.4 |  -7.1  19.2  240  15  8   7.2   4.0
 17500  -6.1  21.0  250  13  7   6.0   3.3 |  -6.0  21.2  245  14  7   7.0   3.8
 17000  -4.8  23.4  250  12  6   5.7   3.2 |  -5.0  23.0  245  13  7   6.8   3.7
 16500  -3.9  25.0  255  11  6   5.9   3.2 |  -3.5  25.7  250  12  6   6.6   3.6
 16000  -3.1  26.4  260  11  6   6.0   3.3 |  -2.6  27.3  250  11  6   6.5   3.6
 15500  -2.2  28.0  260  11  6   6.0   3.3 |  -1.6  29.1  250  10  5   6.6   3.6
 15000  -1.3  29.7  260  11  6   5.9   3.2 |  -0.6  30.9  250   9  5   6.7   3.7
 14500  -0.4  31.3  260  11  6   5.9   3.2 |   0.4  32.7  255   9  5   6.6   3.6
 14000   0.4  32.7  260  11  6   5.9   3.2 |   1.4  34.5  255   8  4   7.3   4.0
 13500   1.3  34.3  260  11  6   5.9   3.3 |   2.5  36.5  255   8  4   7.3   4.0
 13000   2.2  36.0  260  11  6   5.9   3.2 |   3.6  38.5  255   8  4   6.8   3.7
 12500   3.0  37.4  260  11  6   5.9   3.2 |   4.6  40.3  260   9  4   6.8   3.7
 12000   3.9  39.0  260  11  6   6.2   3.4 |   5.5  41.9  260   9  4   5.8   3.2
 11500   4.8  40.6  255  10  5   6.4   3.5 |   6.3  43.3  260   8  4   5.6   3.1
 11000   5.7  42.3  255  10  5   6.1   3.3 |   7.1  44.8  260   7  4   5.2   2.8
 10500   6.5  43.7  260  10  5   5.9   3.2 |   7.7  45.9  260   8  4   5.4   3.0
 10250   6.9  44.4  260  10  5   6.2   3.4 |   8.1  46.6  265   8  4   3.8   2.1
 10000   7.3  45.1  260   9  5   6.7   3.7 |   8.2  46.8  255   6  3   4.5   2.5
  9750   7.8  46.0  260   9  5   6.8   3.8 |   8.6  47.5  255   5  3   6.8   3.7
  9500   8.3  46.9  265  10  5   6.5   3.6 |   9.0  48.2  245   4  2   5.8   3.2
  9250   8.7  47.7  265  10  5   7.8   4.3 |   9.5  49.1  235   3  1   7.8   4.3
  9000   9.4  48.9  265  10  5   8.5   4.7 |  10.1  50.2  220   2  1   9.6   5.3
  8750  10.0  50.0  265   9  5   8.0   4.4 |  10.8  51.4  220   2  1   9.3   5.1
  8500  10.5  50.9  265   8  4   7.8   4.3 |  11.5  52.7  215   2  1   9.1   5.0
  8250  11.1  52.0  265   8  4   9.4   5.1 |  12.1  53.8  210   2  1  10.5   5.8
  8000  11.9  53.4  265   7  4  10.1   5.6 |  13.0  55.4  205   2  1  10.9   6.0
  7750  12.5  54.5  260   6  3   7.7   4.2 |  13.7  56.7  205   2  1   9.1   5.0
  7500  13.0  55.4  260   6  3   7.4   4.0 |  14.4  57.9  205   2  1   8.6   4.7
  7250  13.5  56.3  260   5  3   6.2   3.4 |  15.0  59.0  205   2  1  10.1   5.5
  7000  13.8  56.8  250   5  2   4.5   2.5 |  15.9  60.6  210   2  1  11.3   6.2
  6750  14.1  57.4  240   4  2   3.5   1.9 |  16.7  62.1  210   2  1   9.5   5.2
  6500  14.2  57.6  230   4  2   3.1   1.7 |  17.3  63.1  210   2  1   9.3   5.1
  6250  14.5  58.1  220   3  2   6.0   3.3 |  18.1  64.6  210   2  1  11.3   6.2
  6000  14.9  58.8  210   3  1   7.8   4.3 |  19.0  66.2  210   2  1  12.9   7.1
  5750  15.4  59.7  190   2  1   6.9   3.8 |  19.9  67.8  215   2  1   9.2   5.1
  5500  16.0  60.8  185   2  1  12.4   6.8 |  20.5  68.9  215   2  1  12.6   6.9

           09/15/2017 at 1500 MDT          |       09/15/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +1.8        | CAPE...   +34.7    LI...       -1.3
CINH...     0.0    K Index... +15.7        | CINH...   -37.3    K Index... +23.6
                                           |
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 -58.4 -73.1  230  15  8   2.2   1.2 | -58.1 -72.6  220  11  6   2.5   1.3
 45000 -55.2 -67.4  230  21 11   1.4   0.7 | -54.9 -66.8  225  15  8   0.3   0.2
 40000 -53.2 -63.8  230  27 14   1.9   1.0 | -54.5 -66.1  230  30 15   1.4   0.8
 38000 -51.2 -60.2  230  27 14   3.4   1.8 | -52.0 -61.6  230  29 15   4.5   2.4
 36000 -49.2 -56.6  225  27 14   3.3   1.8 | -49.3 -56.7  230  28 15   4.5   2.4
 34000 -45.6 -50.1  230  26 13   8.1   4.4 | -45.6 -50.1  230  27 14   7.7   4.3
 32000 -40.8 -41.4  230  25 13   8.1   4.4 | -40.9 -41.6  225  27 14   7.8   4.3
 30000 -35.3 -31.5  235  24 12   8.1   4.4 | -35.5 -31.9  225  25 13   8.2   4.5
 29000 -32.9 -27.2  230  23 12   8.1   4.4 | -33.1 -27.6  225  24 13   8.2   4.5
 28000 -30.5 -22.9  230  23 12   8.1   4.4 | -30.6 -23.1  225  24 12   8.2   4.5
 27000 -28.1 -18.6  230  22 11   7.9   4.3 | -28.2 -18.8  225  23 12   8.1   4.4
 26000 -25.8 -14.4  230  21 11   7.9   4.3 | -25.8 -14.4  230  22 12   8.1   4.4
 25000 -23.4 -10.1  230  21 11   7.9   4.3 | -23.3  -9.9  230  22 11   8.0   4.4
 24000 -21.2  -6.2  230  20 10   6.9   3.8 | -21.1  -6.0  230  21 11   6.9   3.8
 23000 -19.1  -2.4  220  19 10   6.9   3.8 | -19.0  -2.2  230  20 10   7.0   3.8
 22000 -17.1   1.2  215  18 10   7.0   3.8 | -16.9   1.6  235  19 10   6.9   3.8
 21000 -14.8   5.4  215  17  9   8.5   4.7 | -15.1   4.8  235  18  9   5.2   2.9
 20000 -12.2  10.0  225  16  8   8.6   4.7 | -13.6   7.5  235  15  8   5.4   2.9
 19500 -10.9  12.4  225  16  8   8.6   4.7 | -12.9   8.8  240  14  7   5.5   3.0
 19000  -9.6  14.7  230  15  8   8.4   4.6 | -12.2  10.0  240  13  7   6.1   3.3
 18500  -8.5  16.7  235  15  8   6.7   3.7 | -11.0  12.2  240  12  6   9.7   5.3
 18000  -7.5  18.5  235  14  7   6.9   3.8 |  -9.6  14.7  235  10  5   9.6   5.3
 17500  -6.5  20.3  235  14  7   6.6   3.6 |  -8.3  17.1  230   9  5   8.9   4.9
 17000  -5.6  21.9  235  12  6   6.5   3.6 |  -7.0  19.4  225   8  4   8.7   4.8
 16500  -4.6  23.7  230  11  6   6.6   3.6 |  -5.8  21.6  220   8  4   8.6   4.7
 16000  -3.7  25.3  225  10  5   7.1   3.9 |  -4.5  23.9  210   7  4   8.0   4.4
 15500  -2.1  28.2  220   8  4   7.3   4.0 |  -2.7  27.1  200   8  4   8.3   4.6
 15000  -1.0  30.2  225   8  4   7.6   4.2 |  -1.4  29.5  195   8  4   8.8   4.9
 14500   0.1  32.2  225   8  4   7.6   4.2 |  -0.1  31.8  190   8  4   8.9   4.9
 14000   1.1  34.0  230   7  4   6.6   3.6 |   1.3  34.3  185   7  4   9.2   5.1
 13500   2.0  35.6  230   7  3   6.6   3.6 |   2.6  36.7  180   7  4   9.2   5.1
 13000   3.0  37.4  220   6  3   8.1   4.4 |   4.0  39.2  180   7  4   8.9   4.9
 12500   4.3  39.7  200   6  3   8.2   4.5 |   5.3  41.5  175   7  3   8.9   4.9
 12000   5.6  42.1  185   6  3   8.1   4.4 |   6.6  43.9  170   6  3   9.2   5.0
 11500   6.7  44.1  180   5  3   8.1   4.5 |   8.0  46.4  165   6  3   9.2   5.1
 11000   7.9  46.2  170   4  2   7.5   4.1 |   9.3  48.7  160   5  3   8.4   4.6
 10500   8.9  48.0  165   4  2   7.2   3.9 |  10.5  50.9  155   4  2   8.5   4.6
 10250   9.5  49.1  160   4  2  10.3   5.6 |  11.2  52.2  155   4  2  10.2   5.6
 10000  10.3  50.5  160   3  2  10.7   5.9 |  12.0  53.6  150   4  2  10.0   5.5
  9750  11.0  51.8  160   3  2   8.6   4.7 |  12.7  54.9  150   4  2   9.0   4.9
  9500  11.6  52.9  160   3  2   9.0   4.9 |  13.4  56.1  150   3  2   9.0   4.9
  9250  12.3  54.1  160   3  2   9.5   5.2 |  14.0  57.2  145   3  2  10.1   5.6
  9000  13.0  55.4  155   3  1   9.9   5.5 |  14.8  58.6  145   3  1  10.3   5.7
  8750  13.7  56.7  160   3  1   9.7   5.3 |  15.5  59.9  145   3  1   9.3   5.1
  8500  14.5  58.1  160   3  1   9.4   5.1 |  16.2  61.2  145   2  1   9.3   5.1
  8250  15.2  59.4  160   3  1  11.0   6.0 |  16.9  62.4  145   2  1  10.1   5.5
  8000  16.0  60.8  160   2  1  11.0   6.1 |  17.7  63.9  140   2  1   9.9   5.4
  7750  16.8  62.2  160   2  1   9.2   5.0 |  18.4  65.1  140   2  1   8.9   4.9
  7500  17.5  63.5  160   2  1   9.1   5.0 |  19.1  66.4  140   1  1   8.7   4.8
  7250  18.2  64.8  160   2  1   9.9   5.4 |  19.7  67.5  140   1  1  10.1   5.5
  7000  18.9  66.0  160   2  1  10.7   5.8 |  20.6  69.1  140   1  1  11.1   6.1
  6750  19.7  67.5  165   2  1  10.1   5.6 |  21.3  70.3  140   1  0   9.7   5.3
  6500  20.5  68.9  165   2  1  10.2   5.6 |  22.0  71.6  140   1  0   9.4   5.2
  6250  21.2  70.2  165   2  1  10.7   5.9 |  22.8  73.0  140   1  0   9.9   5.4
  6000  22.1  71.8  165   2  1  11.4   6.2 |  23.5  74.3  140   1  0  10.3   5.6
  5750  22.9  73.2  170   2  1  10.0   5.5 |  24.3  75.7  000   0  0   9.7   5.3
  5500  23.7  74.7  170   2  1  15.5   8.5 |  25.0  77.0  000   0  0  11.1   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.

CINH (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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