Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231243
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0643 MDT Saturday, September 23, 2017

This forecast is for Saturday, September 23, 2017:

If the trigger temperature of 65.2 F/18.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8599 ft MSL (3314 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 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................. 7448 ft MSL (2162 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....................... 31155 ft MSL (25870 ft AGL)
Wave soaring outlook for Sunday 09/24.......... Poor

Remarks... Increasing showers

Sunrise/Sunset.................... 06:48:34 / 18:54:51 MDT
Total possible sunshine........... 12 hr 6 min 18 sec (726 min 18 sec)
Altitude of sun at 12:51:43 MDT... 49.83 degrees

Upper air data from rawinsonde observation taken on 09/23/2017 at 0600 MDT

Freezing level.................. 13532 ft MSL (8247 ft AGL)
Convective condensation level... 14706 ft MSL (9421 ft AGL)
Lifted condensation level....... 11186 ft MSL (5900 ft AGL)
Lifted index.................... +7.9
K index......................... +22.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -64.0 -83.2   215   74   38  -0.7  -0.4   88.2 190.7    41.4      M    M
 45000  -60.0 -76.0   225   90   46   3.7   2.0   70.2 158.4    33.3      M    M
 40000  -57.6 -71.7   205   80   41   7.6   4.2   51.3 124.3    23.0      M    M
 38000  -52.4 -62.3   205   76   39   8.6   4.7   50.3 122.5    23.0      M    M
 36000  -47.3 -53.1   210   77   39   8.6   4.7   49.1 120.5    22.8      M    M
 34000  -43.2 -45.8   210   77   40   5.5   3.0   46.6 115.9    21.5      M    M
 32000  -38.1 -36.6   200   78   40   8.8   4.8   44.4 112.0    20.5      M    M
 30000  -33.4 -28.1   200   79   41   7.5   4.1   43.2 109.7    20.1      M    M
 29000  -31.1 -24.0   200   76   39   7.5   4.1   42.1 107.9    19.6      M    M
 28000  -28.8 -19.8   200   73   37   7.5   4.1   41.3 106.3    19.1      M    M
 27000  -26.6 -15.9   195   70   36   7.5   4.1   40.5 104.9    18.7      M    M
 26000  -24.3 -11.7   195   67   34   7.5   4.1   39.9 103.8    18.4      M    M
 25000  -22.0  -7.6   200   65   33   7.6   4.2   39.0 102.2    17.9      M    M
 24000  -19.5  -3.1   200   62   32   9.9   5.4   38.4 101.2    17.7      M    M
 23000  -16.6   2.1   205   59   30  10.1   5.5   38.5 101.3    18.0      M    M
 22000  -14.7   5.5   205   57   29   2.3   1.3   37.3  99.1    17.1      M    M
 21000  -14.5   5.9   210   54   28   2.7   1.5   34.2  93.6    14.5      M    M
 20000  -13.1   8.4   215   52   27   5.1   2.8   32.5  90.6    13.2      M    M
 19500  -12.4   9.7   215   51   26   5.1   2.8   31.7  89.1    12.5      M    M
 19000  -11.6  11.1   210   50   26   5.0   2.7   30.9  87.7    11.8      M    M
 18500  -10.6  12.9   210   49   25   8.7   4.8   30.4  86.8    11.5      M    M
 18000   -9.3  15.3   210   50   26   8.4   4.6   30.2  86.3    11.4      M    M
 17500   -8.0  17.6   210   50   26   8.7   4.8   30.0  85.9    11.3      M    M
 17000   -6.9  19.6   210   50   26   5.2   2.9   29.5  85.1    10.9      M    M
 16500   -6.2  20.8   210   51   26   5.5   3.0   28.8  83.8    10.3      M    M
 16000   -5.1  22.8   210   50   26   5.6   3.1   27.7  81.9     9.3      M    M
 15500   -4.2  24.4   205   47   24   7.3   4.0   27.1  80.8     8.7      M    M
 15000   -3.1  26.4   205   45   23   7.6   4.2   26.8  80.2     8.4      M    M
 14500   -2.0  28.4   200   42   22   7.6   4.2   26.5  79.6     8.2      M    M
 14000   -0.9  30.4   195   40   20   7.6   4.2   26.1  79.0     7.9      M    M
 13500    0.3  32.5   190   37   19   7.6   4.2   25.8  78.4     7.6      M    M
 13000    1.4  34.5   185   35   18   7.7   4.2   25.4  77.7     7.2      M    M
 12500    2.5  36.5   180   33   17   7.7   4.2   25.1  77.1     6.9      M    M
 12000    3.6  38.5   175   31   16   7.7   4.2   24.8  76.6     6.7      M    M
 11500    4.7  40.5   180   28   14   7.8   4.3   24.4  75.9     6.3      M    M
 11000    5.8  42.4   180   25   13   8.9   4.9   24.1  75.3     6.0      M    M
 10500    6.2  43.2   195   22   11  -3.5  -1.9   22.9  73.3     5.0      M    M
 10250    6.1  43.0   205   21   11  -1.0  -0.6   22.0  71.6     4.1      M    M
 10000    6.1  43.0   210   20   10   0.8   0.5   21.2  70.2     3.3      M    M
  9750    6.2  43.2   215   19   10   1.9   1.0   20.6  69.0     2.7      M    M
  9500    6.3  43.3   220   18    9   1.6   0.9   19.9  67.9     2.1      M    M
  9250    6.4  43.5   225   17    9   1.7   0.9   19.3  66.8     1.5      M    M
  9000    6.6  43.9   230   16    8   1.6   0.9   18.7  65.6     0.9      M    M
  8750    6.7  44.1   235   12    6   1.6   0.9   18.0  64.5     0.3      M    M
  8500    6.8  44.2   240    8    4   1.7   0.9   17.4  63.4    -0.3    243  1.2
  8250    6.9  44.4   260    5    2   1.6   0.9   16.8  62.2    -0.9    232  1.2
  8000    7.0  44.6   315    3    2   0.8   0.5   16.1  61.1    -1.5    221  1.1
  7750    7.1  44.8   325    3    2   0.6   0.3   15.4  59.8    -2.2    212  1.1
  7500    7.2  45.0   330    4    2   0.2   0.1   14.7  58.5    -2.8    202  1.0
  7250    7.1  44.8   335    4    2  -1.7  -0.9   13.9  57.1    -3.6    196  1.0
  7000    6.9  44.4   340    5    3  -1.9  -1.0   13.0  55.4    -4.5    194  1.0
  6750    6.8  44.2   350    6    3  -3.6  -2.0   12.1  53.8    -5.4    192  1.0
  6500    6.6  43.9   355    7    3   3.5   1.9   11.2  52.2    -6.3    189  1.0
  6250    7.3  45.1   360    8    4  10.8   5.9   11.2  52.1    -6.4    162  0.8
  6000    8.0  46.4   005    9    5   8.9   4.9   11.1  52.1    -6.5    134  0.7
  5750    8.6  47.5   005    7    4   9.5   5.2   11.1  52.0    -6.5    106  0.5
  5500    9.3  48.7   005    6    3   8.9   4.9   11.1  51.9    -6.6     78  0.4

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

           09/23/2017 at 0900 MDT          |       09/23/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       -0.2        | CAPE...    +1.7    LI...       +0.6
CINH...    -0.0    K Index... +28.3        | CINH...    -0.0    K Index... +26.2
                                           |
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 -62.7 -80.9  215  36 18   0.6   0.3 | -63.0 -81.4  210  37 19   0.4   0.2
 45000 -60.9 -77.6  220  46 24   3.8   2.1 | -61.3 -78.3  210  47 24   4.1   2.3
 40000 -55.3 -67.5  210  49 25   4.7   2.6 | -55.1 -67.2  205  49 25   5.2   2.9
 38000 -51.4 -60.5  205  48 25   6.4   3.5 | -51.1 -60.0  200  48 25   6.8   3.7
 36000 -47.6 -53.7  200  47 24   6.4   3.5 | -46.5 -51.7  195  47 24   6.8   3.7
 34000 -42.8 -45.0  200  46 24   7.5   4.1 | -42.2 -44.0  190  46 24   7.5   4.1
 32000 -38.3 -36.9  195  46 24   7.5   4.1 | -37.6 -35.7  190  44 23   7.5   4.1
 30000 -33.7 -28.7  195  45 23   7.8   4.3 | -32.8 -27.0  185  42 22   8.6   4.7
 29000 -31.4 -24.5  195  44 23   7.8   4.3 | -30.2 -22.4  185  41 21   8.6   4.7
 28000 -29.1 -20.4  195  43 22   7.9   4.3 | -27.6 -17.7  185  40 21   8.7   4.8
 27000 -26.9 -16.4  195  42 22   6.8   3.7 | -25.4 -13.7  185  39 20   7.1   3.9
 26000 -24.9 -12.8  195  40 21   6.8   3.7 | -23.3  -9.9  185  38 20   7.1   3.9
 25000 -22.9  -9.2  195  38 19   6.8   3.7 | -21.2  -6.2  190  37 19   7.1   3.9
 24000 -20.9  -5.6  195  36 18   6.8   3.7 | -19.2  -2.6  190  36 18   6.4   3.5
 23000 -18.9  -2.0  195  34 18   6.8   3.7 | -17.3   0.9  190  34 18   6.4   3.5
 22000 -16.9   1.6  195  32 17   6.9   3.8 | -15.4   4.3  195  32 17   6.4   3.5
 21000 -14.9   5.2  200  31 16   7.2   4.0 | -13.6   7.5  195  31 16   5.9   3.2
 20000 -12.8   9.0  200  30 15   7.2   4.0 | -11.8  10.8  200  29 15   6.0   3.3
 19500 -11.2  11.8  200  29 15   7.2   4.0 | -10.5  13.1  200  28 14   6.0   3.3
 19000 -10.1  13.8  200  28 14   6.9   3.8 |  -9.7  14.5  200  27 14   6.0   3.3
 18500  -9.2  15.4  200  27 14   6.5   3.6 |  -8.8  16.2  200  26 14   5.9   3.3
 18000  -8.3  17.1  195  27 14   6.6   3.6 |  -8.0  17.6  200  26 13   5.9   3.2
 17500  -7.3  18.9  195  26 13   6.3   3.4 |  -7.1  19.2  200  25 13   6.1   3.3
 17000  -6.4  20.5  195  25 13   6.3   3.5 |  -6.2  20.8  200  24 12   6.1   3.3
 16500  -5.5  22.1  195  25 13   6.5   3.6 |  -5.3  22.5  200  23 12   6.0   3.3
 16000  -4.5  23.9  195  24 12   6.7   3.7 |  -4.5  23.9  200  23 12   5.8   3.2
 15500  -3.6  25.5  195  23 12   6.7   3.7 |  -3.6  25.5  200  22 11   5.9   3.2
 15000  -2.6  27.3  195  22 11   6.8   3.8 |  -2.7  27.1  200  21 11   6.2   3.4
 14500  -1.6  29.1  195  21 11   6.7   3.7 |  -1.8  28.8  200  20 10   6.1   3.4
 14000  -0.5  31.1  195  20 11   7.9   4.3 |  -0.9  30.4  200  20 10   7.1   3.9
 13500   0.7  33.3  195  19 10   7.8   4.3 |   0.2  32.4  200  19 10   7.0   3.9
 13000   1.8  35.2  195  18  9   7.8   4.3 |   1.2  34.2  200  18  9   7.3   4.0
 12500   3.0  37.4  190  17  9   7.8   4.3 |   2.3  36.1  200  17  9   7.4   4.0
 12000   4.1  39.4  190  16  8   7.4   4.0 |   3.4  38.1  195  16  8   6.8   3.7
 11500   5.1  41.2  185  15  8   7.2   4.0 |   4.3  39.7  195  14  7   6.5   3.6
 11000   6.2  43.2  185  13  7   6.6   3.6 |   5.2  41.4  190  13  7   6.1   3.4
 10500   7.1  44.8  180  12  6   6.4   3.5 |   6.1  43.0  185  12  6   5.8   3.2
 10250   7.5  45.5  180  12  6   5.8   3.2 |   6.5  43.7  180  11  6   6.3   3.4
 10000   7.9  46.2  175  11  6   3.6   2.0 |   6.9  44.4  180  11  6   4.6   2.5
  9750   8.1  46.6  175  10  5   2.6   1.5 |   7.1  44.8  175  11  6   2.9   1.6
  9500   8.3  46.9  170  10  5   3.0   1.6 |   7.3  45.1  175  10  5   3.4   1.9
  9250   8.4  47.1  170   9  5   2.6   1.5 |   7.5  45.5  170  10  5   3.1   1.7
  9000   8.5  47.3  165   8  4  -2.3  -1.2 |   7.7  45.9  165  10  5   0.7   0.4
  8750   8.1  46.6  165   7  3  -6.2  -3.4 |   7.6  45.7  165   9  5  -1.1  -0.6
  8500   7.7  45.9  170   5  3  -5.7  -3.1 |   7.5  45.5  160   9  5  -0.4  -0.2
  8250   7.2  45.0  170   4  2  -6.2  -3.4 |   7.4  45.3  155   8  4  -1.6  -0.9
  8000   6.7  44.1  180   3  2  -6.7  -3.7 |   7.2  45.0  155   8  4  -3.9  -2.1
  7750   6.3  43.3  195   2  1  -5.2  -2.8 |   7.0  44.6  150   7  3  -3.5  -1.9
  7500   5.9  42.6  220   1  1  -5.1  -2.8 |   6.7  44.1  140   6  3  -3.7  -2.1
  7250   5.6  42.1  285   1  0  -1.7  -1.0 |   6.5  43.7  135   5  3  -0.5  -0.3
  7000   5.7  42.3  335   1  0   1.6   0.9 |   6.7  44.1  125   5  2   2.7   1.5
  6750   5.8  42.4  010   1  1   1.9   1.1 |   6.9  44.4  110   5  2   5.7   3.1
  6500   6.0  42.8  030   1  1   5.0   2.8 |   7.6  45.7  105   4  2   9.5   5.2
  6250   6.5  43.7  035   2  1   7.9   4.3 |   8.3  46.9  100   4  2   9.5   5.2
  6000   7.2  45.0  035   2  1   8.5   4.7 |   9.0  48.2  100   4  2  10.2   5.6
  5750   7.8  46.0  035   2  1   9.9   5.4 |   9.8  49.6  095   4  2   9.9   5.4
  5500   8.8  47.8  035   2  1  16.7   9.2 |  10.6  51.1  095   4  2  14.7   8.0

           09/23/2017 at 1500 MDT          |       09/23/2017 at 1800 MDT
                                           |
CAPE...   +36.1    LI...       +0.6        | CAPE...   +75.3    LI...       +0.3
CINH...    -3.9    K Index... +23.9        | CINH...    -7.1    K Index... +25.5
                                           |
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 -63.3 -81.9  210  36 19   0.2   0.1 | -62.7 -80.9  210  34 18   0.1   0.1
 45000 -61.7 -79.1  210  46 24   4.4   2.4 | -61.3 -78.3  205  46 24   4.6   2.5
 40000 -55.1 -67.2  205  48 25   5.6   3.1 | -54.4 -65.9  200  49 25   5.4   3.0
 38000 -50.9 -59.6  200  47 24   7.0   3.8 | -50.3 -58.5  195  49 25   6.9   3.8
 36000 -46.2 -51.2  190  46 24   7.0   3.8 | -45.6 -50.1  190  48 25   6.9   3.8
 34000 -41.5 -42.7  190  44 23   8.2   4.5 | -41.2 -42.2  190  48 24   7.5   4.1
 32000 -36.5 -33.7  185  42 22   8.2   4.5 | -36.7 -34.1  190  47 24   7.5   4.1
 30000 -31.8 -25.2  185  40 21   7.8   4.3 | -32.3 -26.1  190  45 23   7.4   4.0
 29000 -29.5 -21.1  185  39 20   7.8   4.3 | -30.1 -22.2  190  44 22   7.4   4.0
 28000 -27.1 -16.8  185  39 20   7.9   4.3 | -27.9 -18.2  190  42 22   7.4   4.1
 27000 -24.9 -12.8  185  38 19   7.3   4.0 | -25.7 -14.3  190  41 21   7.0   3.8
 26000 -22.8  -9.0  185  37 19   7.3   4.0 | -23.6 -10.5  190  40 21   7.0   3.8
 25000 -20.6  -5.1  185  36 18   7.3   4.0 | -21.6  -6.9  190  39 20   7.0   3.8
 24000 -18.5  -1.3  190  35 18   6.3   3.4 | -19.5  -3.1  190  38 19   7.0   3.9
 23000 -16.7   1.9  190  34 17   6.4   3.5 | -17.4   0.7  195  37 19   7.1   3.9
 22000 -14.8   5.4  190  33 17   6.4   3.5 | -15.3   4.5  195  36 18   7.1   3.9
 21000 -13.0   8.6  195  32 17   5.9   3.2 | -13.2   8.2  200  34 18   6.7   3.7
 20000 -11.2  11.8  195  32 16   5.9   3.2 | -11.2  11.8  200  33 17   6.8   3.7
 19500 -10.4  13.3  200  31 16   5.9   3.3 |  -9.8  14.4  205  31 16   6.8   3.7
 19000  -9.1  15.6  200  31 16   5.8   3.2 |  -8.8  16.2  205  31 16   6.7   3.7
 18500  -8.3  17.1  205  31 16   5.5   3.0 |  -7.8  18.0  205  30 15   6.7   3.7
 18000  -7.5  18.5  205  30 15   5.5   3.0 |  -6.8  19.8  205  28 15   6.7   3.7
 17500  -6.6  20.1  205  29 15   5.6   3.1 |  -5.9  21.4  205  27 14   6.3   3.5
 17000  -5.8  21.6  210  28 15   5.6   3.1 |  -5.0  23.0  205  26 13   6.3   3.5
 16500  -5.0  23.0  210  27 14   5.8   3.2 |  -4.1  24.6  205  25 13   5.9   3.3
 16000  -4.1  24.6  210  26 14   6.2   3.4 |  -3.4  25.9  205  23 12   5.1   2.8
 15500  -3.2  26.2  215  25 13   6.2   3.4 |  -2.7  27.1  205  21 11   5.2   2.8
 15000  -2.3  27.9  215  24 13   6.7   3.7 |  -2.0  28.4  205  20 10   5.1   2.8
 14500  -1.3  29.7  215  23 12   6.7   3.6 |  -1.2  29.8  200  19 10   5.1   2.8
 14000  -0.3  31.5  215  22 12   7.4   4.1 |  -0.5  31.1  200  17  9   6.1   3.4
 13500   0.8  33.4  210  21 11   7.4   4.1 |   0.4  32.7  195  16  8   6.3   3.5
 13000   1.9  35.4  210  20 10   7.0   3.8 |   1.4  34.5  195  15  8   7.2   4.0
 12500   2.8  37.0  205  19 10   6.8   3.7 |   2.5  36.5  190  15  8   7.8   4.3
 12000   3.8  38.8  205  18  9   6.6   3.6 |   3.6  38.5  185  14  7   7.5   4.1
 11500   4.8  40.6  200  17  9   6.5   3.6 |   4.7  40.5  185  14  7   7.0   3.8
 11000   5.7  42.3  200  15  8   5.6   3.1 |   5.7  42.3  185  14  7   6.1   3.3
 10500   6.3  43.3  195  14  7   4.8   2.6 |   6.3  43.3  180  14  7   4.1   2.3
 10250   6.7  44.1  190  14  7   4.7   2.6 |   6.7  44.1  180  14  7   6.8   3.7
 10000   7.0  44.6  190  13  7   3.6   2.0 |   7.2  45.0  180  13  7   6.5   3.6
  9750   7.2  45.0  185  13  7   2.9   1.6 |   7.5  45.5  180  13  7   2.7   1.5
  9500   7.4  45.3  185  12  6   2.9   1.6 |   7.7  45.9  180  12  6   2.9   1.6
  9250   7.6  45.7  180  12  6   3.7   2.0 |   7.8  46.0  180  12  6   2.7   1.5
  9000   7.8  46.0  175  11  6   3.8   2.1 |   8.0  46.4  175  12  6   3.0   1.7
  8750   8.0  46.4  170  11  6   2.7   1.5 |   8.2  46.8  175  11  6   3.5   1.9
  8500   8.2  46.8  170  10  5   2.8   1.5 |   8.5  47.3  170  10  5   3.4   1.9
  8250   8.3  46.9  165  10  5   2.5   1.4 |   8.7  47.7  170   9  5   3.6   2.0
  8000   8.4  47.1  160   9  5   2.3   1.3 |   8.9  48.0  165   8  4   4.9   2.7
  7750   8.6  47.5  150   9  4   3.2   1.7 |   9.3  48.7  165   7  4   5.2   2.9
  7500   8.9  48.0  145   8  4   4.1   2.2 |   9.7  49.5  155   6  3   4.6   2.5
  7250   9.1  48.4  140   8  4   2.6   1.5 |  10.0  50.0  150   5  3   5.0   2.7
  7000   9.2  48.6  130   7  3   0.9   0.5 |  10.4  50.7  140   4  2   5.4   3.0
  6750   9.4  48.9  120   6  3   4.7   2.6 |  10.8  51.4  120   3  2   6.3   3.4
  6500   9.9  49.8  115   6  3   7.6   4.2 |  11.3  52.3  105   3  1   6.5   3.6
  6250  10.5  50.9  110   6  3   7.4   4.1 |  11.8  53.2  085   3  1   7.6   4.2
  6000  11.0  51.8  105   5  3   8.1   4.4 |  12.4  54.3  065   2  1   8.7   4.8
  5750  11.6  52.9  095   5  3   7.7   4.2 |  13.0  55.4  040   3  1   8.5   4.7
  5500  12.3  54.1  100   5  2  12.7   7.0 |  13.7  56.7  045   3  1  10.4   5.7
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

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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