Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230017
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1817 MDT Friday, September 22, 2017

This forecast is for Saturday, September 23, 2017:

If the trigger temperature of 70.4 F/21.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8701 ft MSL (3388 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
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................. 8320 ft MSL (3007 ft AGL)
Thermal soaring outlook for Sunday 09/24....... Poor

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....................... 45917 ft MSL (40604 ft AGL)
Wave soaring outlook for Sunday 09/24.......... Poor

Remarks... Southerly flow aloft ahead of deep western u. S. Trough.

Sunrise/Sunset.................... 06:48:36 / 18:54:47 MDT
Total possible sunshine........... 12 hr 6 min 11 sec (726 min 11 sec)
Altitude of sun at 12:51:42 MDT... 49.81 degrees

Upper air data from numerical model forecast valid on 09/23/2017 at 0600 MDT

Freezing level.................. 14057 ft MSL (8744 ft AGL)
Convective condensation level... 13107 ft MSL (7794 ft AGL)
Lifted condensation level....... 9993 ft MSL (4680 ft AGL)
Lifted index.................... +3.2
K index......................... +24.7

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  -63.7 -82.7   215   34   17   1.2   0.6      M     M       M      M    M
 45000  -61.2 -78.2   220   47   24   3.3   1.8      M     M       M      M    M
 40000  -56.2 -69.2   210   45   23   4.9   2.7      M     M       M      M    M
 38000  -52.1 -61.8   210   44   22   6.8   3.7      M     M       M      M    M
 36000  -48.1 -54.6   205   42   22   6.8   3.7      M     M       M      M    M
 34000  -43.7 -46.7   205   41   21   7.7   4.2      M     M       M      M    M
 32000  -38.5 -37.3   205   40   21   7.7   4.2      M     M       M      M    M
 30000  -33.6 -28.5   200   39   20   8.5   4.7   42.5 108.5    18.8      M    M
 29000  -31.0 -23.8   200   38   20   8.5   4.7   42.0 107.7    18.7      M    M
 28000  -28.4 -19.1   200   38   19   8.6   4.7   41.7 107.1    18.6      M    M
 27000  -26.1 -15.0   200   36   19   7.3   4.0   40.9 105.6    18.2      M    M
 26000  -23.9 -11.0   200   35   18   7.3   4.0   39.9 103.9    17.6      M    M
 25000  -21.7  -7.1   200   33   17   7.3   4.0   39.1 102.4    17.2      M    M
 24000  -19.6  -3.3   200   32   16   6.6   3.6   38.1 100.6    16.5      M    M
 23000  -17.7   0.1   200   31   16   6.6   3.6   36.9  98.4    15.7      M    M
 22000  -15.7   3.7   200   31   16   6.6   3.6   35.8  96.5    15.0      M    M
 21000  -13.9   7.0   205   30   16   5.2   2.9   34.5  94.0    14.0      M    M
 20000  -12.4   9.7   205   30   15   5.3   2.9   32.8  91.1    12.7      M    M
 19500  -11.7  10.9   205   29   15   5.3   2.9   32.1  89.7    12.0      M    M
 19000  -10.9  12.4   210   29   15   5.3   2.9   31.3  88.4    11.4      M    M
 18500  -10.0  14.0   210   29   15   7.0   3.9   30.7  87.3    11.0      M    M
 18000   -9.0  15.8   210   30   15   6.9   3.8   30.2  86.4    10.5      M    M
 17500   -8.0  17.6   210   30   15   6.6   3.6   29.8  85.6    10.1      M    M
 17000   -6.7  19.9   210   30   15   6.5   3.6   28.9  84.0     9.4      M    M
 16500   -5.7  21.7   210   29   15   7.3   4.0   28.4  83.1     8.9      M    M
 16000   -4.6  23.7   210   29   15   7.6   4.2   28.0  82.4     8.6      M    M
 15500   -3.5  25.7   205   29   15   8.0   4.4   27.7  81.8     8.3      M    M
 15000   -2.2  28.0   205   28   14   8.9   4.9   27.5  81.5     8.2      M    M
 14500   -0.9  30.4   205   27   14   8.9   4.9   27.3  81.2     8.1      M    M
 14000    0.3  32.5   205   27   14   7.9   4.3   27.1  80.8     7.9      M    M
 13500    1.5  34.7   205   26   13   7.9   4.4   26.8  80.3     7.6      M    M
 13000    2.6  36.7   205   25   13   8.2   4.5   26.5  79.8     7.3      M    M
 12500    3.8  38.8   205   25   13   8.2   4.5   26.3  79.3     7.1      M    M
 12000    5.0  41.0   205   24   13   8.6   4.7   26.1  78.9     6.9      M    M
 11500    6.2  43.2   205   23   12   8.8   4.8   25.9  78.6     6.7      M    M
 11000    7.4  45.3   205   22   11   6.8   3.7   25.7  78.2     6.4      M    M
 10500    8.3  46.9   205   19   10   6.9   3.8   25.1  77.2     5.9      M    M
 10250    8.7  47.7   200   17    9   3.9   2.1   24.8  76.7     5.6      M    M
 10000    8.8  47.8   200   16    8   1.3   0.7   24.2  75.5     5.0      M    M
  9750    9.0  48.2   195   14    7   2.2   1.2   23.6  74.4     4.4      M    M
  9500    9.1  48.4   195   13    6   2.3   1.3   23.0  73.4     3.8      M    M
  9250    9.2  48.6   190   11    6   0.9   0.5   22.4  72.3     3.3      M    M
  9000    9.0  48.2   185    9    5  -9.4  -5.2   21.4  70.5     2.3      M    M
  8750    7.9  46.2   190    8    4 -16.0  -8.8   19.5  67.1     0.4      M    M
  8500    6.7  44.1   195    7    3 -18.2 -10.0   17.5  63.5    -1.5    331  1.7
  8250    5.5  41.9   205    5    3  -8.4  -4.6   15.5  59.9    -3.4    360  1.8
  8000    5.5  41.9   215    4    2   5.0   2.7   14.8  58.6    -4.1    352  1.8
  7750    5.8  42.4   225    4    2   6.6   3.6   14.4  58.0    -4.5    334  1.7
  7500    6.4  43.5   230    3    2   8.0   4.4   14.3  57.7    -4.7    310  1.6
  7250    6.9  44.4   240    2    1   6.0   3.3   14.1  57.4    -5.0    288  1.5
  7000    7.3  45.1   285    1    0   5.6   3.1   13.7  56.7    -5.3    269  1.4
  6750    7.6  45.7   020    2    1   2.4   1.3   13.4  56.1    -5.7    252  1.3
  6500    7.7  45.9   030    3    2   3.8   2.1   12.7  54.9    -6.4    241  1.2
  6250    8.3  46.9   030    4    2   9.6   5.2   12.6  54.6    -6.6    217  1.1
  6000    8.9  48.0   025    4    2   9.8   5.4   12.6  54.6    -6.6    189  1.0
  5750    9.6  49.3   025    4    2   9.1   5.0   12.6  54.6    -6.7    161  0.8
  5500   10.3  50.5   025    4    2  10.3   5.6   12.5  54.6    -6.7    133  0.7

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

           09/23/2017 at 0900 MDT          |       09/23/2017 at 1200 MDT
                                           |
CAPE...    +0.7    LI...        0.0        | CAPE...     0.0    LI...       -0.2
CINH...     0.0    K Index... +29.5        | CINH...     0.0    K Index... +26.9
                                           |
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 -62.4 -80.3  220  36 19   0.2   0.1 | -63.4 -82.1  220  37 19  -0.5  -0.3
 45000 -61.1 -78.0  220  48 25   3.8   2.1 | -62.5 -80.5  215  50 26   4.7   2.6
 40000 -55.3 -67.5  210  50 26   5.3   2.9 | -55.4 -67.7  205  51 26   6.7   3.7
 38000 -51.1 -60.0  205  49 25   7.1   3.9 | -50.7 -59.3  200  50 26   7.7   4.2
 36000 -46.8 -52.2  200  47 24   7.1   3.9 | -46.1 -51.0  200  49 25   7.7   4.2
 34000 -42.1 -43.8  200  47 24   6.9   3.8 | -41.5 -42.7  195  47 24   7.4   4.0
 32000 -37.9 -36.2  200  47 24   6.9   3.8 | -36.6 -33.9  190  45 23   7.4   4.0
 30000 -33.2 -27.8  200  46 24   8.3   4.6 | -31.8 -25.2  190  43 22   8.3   4.6
 29000 -30.7 -23.3  200  46 23   8.3   4.6 | -29.3 -20.7  190  42 22   8.4   4.6
 28000 -28.2 -18.8  200  45 23   8.5   4.6 | -26.8 -16.2  190  42 22   8.5   4.7
 27000 -26.2 -15.2  200  43 22   5.9   3.2 | -24.5 -12.1  195  41 21   7.1   3.9
 26000 -24.5 -12.1  200  41 21   6.0   3.3 | -22.4  -8.3  195  40 21   7.1   3.9
 25000 -22.8  -9.0  200  39 20   6.1   3.3 | -20.4  -4.7  195  40 20   7.2   3.9
 24000 -20.9  -5.6  200  37 19   6.8   3.7 | -18.4  -1.1  195  38 20   5.8   3.2
 23000 -19.0  -2.2  200  34 17   6.8   3.7 | -16.7   1.9  200  36 19   5.9   3.2
 22000 -17.0   1.4  200  31 16   6.8   3.7 | -15.0   5.0  200  34 17   5.9   3.2
 21000 -14.8   5.4  200  29 15   7.8   4.3 | -13.3   8.1  200  31 16   5.6   3.1
 20000 -12.5   9.5  195  27 14   7.9   4.3 | -11.7  10.9  200  28 14   5.7   3.1
 19500 -11.4  11.5  195  26 13   7.9   4.3 | -10.9  12.4  200  26 13   5.7   3.1
 19000 -10.2  13.6  195  25 13   7.9   4.3 | -10.0  14.0  205  24 13   5.7   3.1
 18500  -9.2  15.4  195  24 12   6.7   3.7 |  -9.1  15.6  205  23 12   7.6   4.1
 18000  -8.2  17.2  195  23 12   6.8   3.7 |  -8.0  17.6  200  22 11   7.4   4.1
 17500  -7.2  19.0  195  23 12   6.5   3.6 |  -6.9  19.6  200  20 10   7.2   4.1
 17000  -6.3  20.7  195  22 11   6.3   3.5 |  -5.9  21.4  200  19 10   7.1   3.9
 16500  -4.9  23.2  200  21 11   6.3   3.4 |  -4.9  23.2  200  18  9   7.0   3.8
 16000  -4.0  24.8  200  21 11   6.3   3.4 |  -4.0  24.8  195  18  9   5.9   3.2
 15500  -3.1  26.4  200  20 10   6.3   3.5 |  -2.7  27.1  195  17  9   5.7   3.2
 15000  -2.2  28.0  200  20 10   6.4   3.5 |  -1.9  28.6  200  16  8   5.1   2.8
 14500  -1.2  29.8  205  19 10   6.5   3.5 |  -1.1  30.0  200  15  8   5.0   2.8
 14000  -0.3  31.5  205  19 10   5.7   3.1 |  -0.3  31.5  205  14  7   6.1   3.4
 13500   0.5  32.9  210  19 10   5.6   3.1 |   0.6  33.1  205  13  7   6.0   3.3
 13000   1.5  34.7  210  19 10   7.9   4.3 |   1.5  34.7  205  12  6   6.2   3.4
 12500   2.6  36.7  205  17  9   7.8   4.3 |   2.4  36.3  195  11  6   6.2   3.4
 12000   3.8  38.8  200  16  8   8.8   4.8 |   3.3  37.9  190  10  5   7.7   4.2
 11500   5.1  41.2  200  15  8   8.9   4.9 |   4.5  40.1  185  10  5   8.0   4.4
 11000   6.4  43.5  195  14  7   8.2   4.5 |   5.6  42.1  180  10  5   6.9   3.8
 10500   7.5  45.5  195  13  7   8.8   4.8 |   6.5  43.7  180  10  5   7.5   4.1
 10250   8.1  46.6  190  13  7   4.9   2.7 |   7.0  44.6  175  10  5   2.8   1.6
 10000   8.3  46.9  190  13  6   3.0   1.7 |   7.0  44.6  175  10  5   1.9   1.0
  9750   8.6  47.5  185  12  6   5.2   2.9 |   7.4  45.3  170  10  5   5.9   3.2
  9500   9.0  48.2  180  11  6   5.5   3.0 |   7.7  45.9  170  10  5   4.9   2.7
  9250   9.3  48.7  175  11  5   2.2   1.2 |   8.0  46.4  165  10  5   4.7   2.6
  9000   9.1  48.4  170  10  5  -7.1  -3.9 |   8.3  46.9  165   9  5   1.9   1.1
  8750   8.4  47.1  175   9  4 -11.0  -6.0 |   8.3  46.9  160   9  4  -0.1  -0.0
  8500   7.5  45.5  180   7  4 -11.8  -6.5 |   8.2  46.8  160   8  4   0.7   0.4
  8250   6.7  44.1  185   6  3  -8.3  -4.6 |   8.2  46.8  155   7  4  -1.8  -1.0
  8000   6.3  43.3  195   5  3  -3.6  -2.0 |   7.9  46.2  150   6  3  -4.7  -2.6
  7750   6.1  43.0  205   4  2  -0.2  -0.1 |   7.6  45.7  145   5  3  -3.9  -2.2
  7500   6.2  43.2  215   3  2   2.5   1.4 |   7.4  45.3  140   4  2  -3.6  -2.0
  7250   6.4  43.5  225   2  1   1.6   0.9 |   7.2  45.0  130   3  2  -1.9  -1.1
  7000   6.5  43.7  000   0  0   2.6   1.4 |   7.1  44.8  115   3  2  -0.4  -0.2
  6750   6.6  43.9  055   1  1  -1.6  -0.9 |   7.1  44.8  095   3  1  -2.0  -1.1
  6500   6.5  43.7  060   3  1   2.4   1.3 |   7.0  44.6  075   3  2   3.2   1.7
  6250   7.1  44.8  060   3  2  10.7   5.9 |   7.6  45.7  070   3  2  10.3   5.6
  6000   7.9  46.2  060   3  2   9.9   5.4 |   8.4  47.1  065   3  2   9.6   5.3
  5750   8.6  47.5  060   3  2  10.5   5.7 |   9.1  48.4  060   3  2  11.9   6.6
  5500   9.5  49.1  060   3  1  12.6   6.9 |  10.3  50.5  060   3  2  20.6  11.3

           09/23/2017 at 1500 MDT          |       09/23/2017 at 1800 MDT
                                           |
CAPE...    +2.6    LI...       +0.9        | CAPE...    +3.6    LI...       +0.7
CINH...     0.0    K Index... +22.0        | CINH...     0.0    K Index... +21.7
                                           |
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  215  39 20  -1.1  -0.6 | -62.6 -80.7  210  37 19  -0.5  -0.3
 45000 -63.7 -82.7  215  52 27   5.2   2.8 | -61.8 -79.2  210  49 25   4.8   2.6
 40000 -55.8 -68.4  195  48 25   7.3   4.0 | -54.2 -65.6  195  52 27   6.9   3.8
 38000 -50.7 -59.3  190  44 23   8.5   4.7 | -49.9 -57.8  190  50 26   7.1   3.9
 36000 -45.6 -50.1  185  41 21   8.5   4.7 | -45.6 -50.1  185  48 25   7.1   3.9
 34000 -40.2 -40.4  185  38 20   7.6   4.2 | -40.9 -41.6  185  47 24   8.5   4.6
 32000 -35.6 -32.1  185  36 19   7.7   4.2 | -35.8 -32.4  185  46 23   8.4   4.6
 30000 -30.8 -23.4  190  36 18   8.2   4.5 | -31.2 -24.2  185  46 24   7.0   3.9
 29000 -28.4 -19.1  190  36 18   8.2   4.5 | -29.1 -20.4  185  47 24   7.0   3.9
 28000 -25.9 -14.6  190  35 18   8.3   4.6 | -26.5 -15.7  190  48 25   7.0   3.9
 27000 -23.8 -10.8  190  35 18   6.9   3.8 | -24.4 -11.9  190  47 24   7.0   3.8
 26000 -21.7  -7.1  190  34 18   6.9   3.8 | -22.3  -8.1  195  46 24   7.0   3.8
 25000 -19.7  -3.5  190  34 17   6.9   3.8 | -20.1  -4.2  195  46 23   7.0   3.8
 24000 -17.7   0.1  195  33 17   6.0   3.3 | -18.2  -0.8  200  44 23   5.9   3.3
 23000 -15.9   3.4  195  34 17   6.1   3.3 | -16.4   2.5  200  41 21   6.0   3.3
 22000 -14.1   6.6  200  34 18   6.1   3.3 | -14.6   5.7  205  38 20   6.0   3.3
 21000 -12.5   9.5  205  34 18   5.1   2.8 | -13.0   8.6  205  34 18   5.4   3.0
 20000 -11.0  12.2  205  33 17   5.1   2.8 | -11.4  11.5  210  29 15   5.6   3.1
 19500 -10.2  13.6  210  33 17   5.1   2.8 | -10.7  12.7  210  26 14   5.8   3.2
 19000  -9.5  14.9  210  33 17   5.0   2.8 |  -9.9  14.2  210  24 12   5.9   3.2
 18500  -8.7  16.3  210  32 16   5.7   3.1 |  -9.0  15.8  215  21 11   6.5   3.6
 18000  -7.9  17.8  215  30 15   5.7   3.1 |  -8.1  17.4  215  18  9   6.5   3.5
 17500  -7.1  19.2  215  28 15   6.1   3.3 |  -7.1  19.2  215  15  8   7.0   3.8
 17000  -6.1  21.0  215  26 13   6.7   3.6 |  -6.0  21.2  215  14  7   7.5   4.1
 16500  -4.6  23.7  215  22 12   6.6   3.6 |  -4.9  23.2  215  13  7   7.6   4.2
 16000  -3.7  25.3  220  21 11   6.6   3.6 |  -3.8  25.2  210  12  6   7.1   3.9
 15500  -2.7  27.1  220  20 10   6.5   3.6 |  -2.8  27.0  205  11  6   7.2   3.9
 15000  -1.8  28.8  215  18  9   5.5   3.0 |  -1.8  28.8  200  11  5   5.6   3.1
 14500  -1.0  30.2  215  17  9   5.8   3.2 |  -1.1  30.0  190  10  5   5.2   2.9
 14000  -0.3  31.5  210  16  8   4.2   2.3 |  -0.4  31.3  185  10  5   4.7   2.6
 13500   0.3  32.5  205  15  8   4.2   2.3 |   0.5  32.9  180  11  5   4.1   2.2
 13000   0.9  33.6  200  14  7   5.1   2.8 |   1.1  34.0  175  11  6   5.4   2.9
 12500   1.7  35.1  195  13  7   5.3   2.9 |   1.9  35.4  180  11  6   5.6   3.1
 12000   2.4  36.3  190  13  7   4.9   2.7 |   2.7  36.9  185  12  6   5.7   3.1
 11500   3.1  37.6  185  12  6   4.7   2.6 |   3.5  38.3  185  12  6   5.7   3.1
 11000   3.7  38.7  180  12  6   4.3   2.4 |   4.3  39.7  190  13  7   4.3   2.4
 10500   4.3  39.7  180  12  6   3.8   2.1 |   4.8  40.6  190  13  7   3.6   2.0
 10250   4.6  40.3  175  12  6   5.5   3.0 |   5.0  41.0  190  13  7   3.6   2.0
 10000   5.0  41.0  175  12  6   6.6   3.6 |   5.2  41.4  190  13  7   3.1   1.7
  9750   5.4  41.7  170  13  6   5.6   3.1 |   5.4  41.7  190  13  7   2.8   1.5
  9500   5.8  42.4  170  13  7   6.3   3.5 |   5.6  42.1  185  13  7   2.6   1.4
  9250   6.2  43.2  170  14  7   4.8   2.6 |   5.8  42.4  185  13  7   3.9   2.1
  9000   6.5  43.7  170  14  7   3.8   2.1 |   6.1  43.0  185  12  6   5.9   3.3
  8750   6.8  44.2  165  13  7   5.0   2.8 |   6.5  43.7  180  11  6   5.8   3.2
  8500   7.2  45.0  165  13  7   5.7   3.1 |   6.9  44.4  180  10  5   5.8   3.2
  8250   7.5  45.5  160  13  7   4.1   2.2 |   7.3  45.1  175   9  5   4.9   2.7
  8000   7.7  45.9  160  12  6   2.0   1.1 |   7.6  45.7  175   8  4   3.0   1.7
  7750   7.9  46.2  155  11  5   2.3   1.2 |   7.8  46.0  170   6  3   2.0   1.1
  7500   8.1  46.6  150  10  5   2.7   1.5 |   7.9  46.2  160   5  2   1.8   1.0
  7250   8.2  46.8  145   9  5   1.0   0.5 |   8.0  46.4  150   4  2   1.4   0.8
  7000   8.2  46.8  140   8  4  -0.4  -0.2 |   8.1  46.6  125   3  1   1.1   0.6
  6750   8.3  46.9  130   8  4   0.8   0.4 |   8.2  46.8  085   2  1   1.0   0.6
  6500   8.4  47.1  120   7  4   3.2   1.7 |   8.3  46.9  055   3  2   2.7   1.5
  6250   8.7  47.7  110   6  3   5.8   3.2 |   8.6  47.5  035   3  2   6.3   3.4
  6000   9.2  48.6  100   5  3   5.7   3.1 |   9.1  48.4  025   4  2   7.1   3.9
  5750   9.6  49.3  090   5  2   7.8   4.3 |   9.7  49.5  015   4  2   7.6   4.2
  5500  10.4  50.7  080   4  2  14.9   8.2 |  10.3  50.5  005   4  2  11.9   6.5
________________________________________________________________________________

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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