Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241254
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0654 MDT Sunday, September 24, 2017

This forecast is for Sunday, September 24, 2017:

If the trigger temperature of 58.1 F/14.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7844 ft MSL (2559 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 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................. 6102 ft MSL (817 ft AGL)
Thermal soaring outlook for Monday 09/25....... Poor

Wave Soaring Index............................. Excellent
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 17851 ft MSL (12566 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 35344 ft MSL (30059 ft AGL)
Wave soaring outlook for Monday 09/25.......... Poor

Remarks... Showers redeveloping this afternoon

Sunrise/Sunset.................... 06:49:30 / 18:53:13 MDT
Total possible sunshine........... 12 hr 3 min 42 sec (723 min 42 sec)
Altitude of sun at 12:51:22 MDT... 49.44 degrees

Upper air data from rawinsonde observation taken on 09/24/2017 at 0600 MDT

Freezing level.................. 11228 ft MSL (5943 ft AGL)
Convective condensation level... 11551 ft MSL (6266 ft AGL)
Lifted condensation level....... 9085 ft MSL (3799 ft AGL)
Lifted index.................... +7.7
K index......................... +21.8

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  -59.3 -74.7   220   58   30   1.7   1.0   96.3 205.3    49.0      M    M
 45000  -57.5 -71.5   205   99   51   3.8   2.1   74.8 166.6    39.1      M    M
 40000  -51.8 -61.2   190   96   50   3.7   2.0   60.7 141.3    32.6      M    M
 38000  -48.8 -55.8   190  102   52   5.1   2.8   56.1 132.9    30.3      M    M
 36000  -45.7 -50.3   190  107   55   5.1   2.8   52.2 126.0    28.4      M    M
 34000  -42.6 -44.7   190  107   55   5.0   2.7   48.5 119.4    26.4      M    M
 32000  -37.9 -36.2   190  100   51   7.8   4.3   45.9 114.6    25.2      M    M
 30000  -33.3 -27.9   190   92   48   5.2   2.9   44.3 111.7    24.7      M    M
 29000  -31.7 -25.1   185   86   44   5.4   3.0   42.6 108.7    23.7      M    M
 28000  -30.1 -22.2   180   81   42   5.4   3.0   41.0 105.9    22.7      M    M
 27000  -28.4 -19.1   185   78   40   5.4   3.0   39.2 102.6    21.6      M    M
 26000  -26.8 -16.2   190   76   39   5.4   3.0   37.6  99.7    20.6      M    M
 25000  -25.2 -13.4   195   75   39   5.4   3.0   36.1  97.0    19.6      M    M
 24000  -23.4 -10.1   195   70   36   7.5   4.1   34.5  94.2    18.6      M    M
 23000  -21.0  -5.8   195   67   35   8.1   4.5   33.8  92.8    18.2      M    M
 22000  -18.6  -1.5   195   65   33   8.1   4.5   33.2  91.7    17.9      M    M
 21000  -16.1   3.0   195   63   32   8.1   4.5   32.6  90.8    17.6      M    M
 20000  -13.9   7.0   195   60   31   4.3   2.4   31.9  89.5    17.2      M    M
 19500  -13.3   8.1   195   58   30   3.8   2.1   30.9  87.7    16.4      M    M
 19000  -12.8   9.0   200   57   29   4.5   2.5   29.8  85.7    15.6      M    M
 18500  -12.9   8.8   200   55   28  -9.0  -4.9   28.0  82.3    14.1      M    M
 18000  -14.0   6.8   205   55   28  -3.3  -1.8   25.2  77.3    11.6      M    M
 17500  -14.3   6.3   205   52   27   9.1   5.0   23.2  73.7     9.9      M    M
 17000  -12.8   9.0   210   49   25   8.7   4.8   23.3  74.0    10.0      M    M
 16500  -11.0  12.2   210   45   23  12.4   6.8   23.9  74.9    10.4      M    M
 16000   -9.3  15.3   215   40   21   6.4   3.5   23.4  74.1    10.0      M    M
 15500   -8.3  17.1   215   37   19   6.3   3.4   22.8  73.0     9.5      M    M
 15000   -7.4  18.7   215   34   18   6.3   3.4   22.2  72.0     9.0      M    M
 14500   -6.5  20.3   210   31   16   6.3   3.4   21.7  71.0     8.5      M    M
 14000   -5.6  21.9   210   29   15   6.3   3.4   21.1  70.0     8.1      M    M
 13500   -4.6  23.7   210   28   14   6.3   3.4   20.5  68.9     7.5      M    M
 13000   -3.7  25.3   210   26   14   6.3   3.4   19.9  67.8     7.0      M    M
 12500   -2.8  27.0   215   25   13   6.3   3.5   19.3  66.8     6.5      M    M
 12000   -1.9  28.6   215   24   12   7.2   4.0   18.8  65.8     6.0      M    M
 11500   -0.6  30.9   210   20   10  10.0   5.5   18.7  65.7     5.8      M    M
 11000    0.8  33.4   205   17    9   6.9   3.8   18.8  65.8     5.8      M    M
 10500    1.2  34.2   195   14    7   3.0   1.7   17.7  63.9     4.8      M    M
 10250    1.4  34.5   190   13    7   2.8   1.5   17.2  62.9     4.3      M    M
 10000    1.7  35.1   185   12    6   3.7   2.0   16.6  62.0     3.8      M    M
  9750    2.0  35.6   185   11    6   4.3   2.4   16.2  61.2     3.4      M    M
  9500    2.3  36.1   185   10    5   4.1   2.3   15.8  60.4     3.0      M    M
  9250    2.6  36.7   180   10    5   4.2   2.3   15.3  59.6     2.6      M    M
  9000    3.0  37.4   180    9    5   4.2   2.3   14.9  58.9     2.2      M    M
  8750    3.3  37.9   175    7    4   4.2   2.3   14.5  58.1     1.8      M    M
  8500    3.6  38.5   165    5    3   4.1   2.2   14.0  57.3     1.4      M    M
  8250    3.9  39.0   140    4    2   4.4   2.4   13.6  56.5     1.0      M    M
  8000    4.2  39.6   105    3    2   0.4   0.2   13.1  55.6     0.6      M    M
  7750    4.0  39.2   120    3    1  -2.4  -1.3   12.2  54.0    -0.4    189  1.0
  7500    3.8  38.8   130    3    1  -2.7  -1.5   11.3  52.4    -1.3    187  1.0
  7250    3.6  38.5   145    3    1   1.5   0.8   10.4  50.8    -2.2    185  0.9
  7000    4.0  39.2   160    3    2   8.1   4.5   10.1  50.2    -2.5    166  0.8
  6750    4.6  40.3   150    3    2   8.5   4.7   10.0  50.0    -2.6    141  0.7
  6500    5.2  41.4   140    3    2   8.4   4.6    9.9  49.9    -2.8    115  0.6
  6250    5.8  42.4   130    4    2   8.4   4.6    9.8  49.7    -2.9     90  0.5
  6000    6.4  43.5   125    4    2   8.5   4.6    9.7  49.5    -3.0     65  0.3
  5750    7.0  44.6   120    4    2   8.5   4.6    9.6  49.4    -3.2     40  0.2
  5500    7.6  45.7   115    5    2   8.5   4.7    9.5  49.2    -3.3     15  0.1

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

           09/24/2017 at 0900 MDT          |       09/24/2017 at 1200 MDT
                                           |
CAPE...    +5.1    LI...       +0.7        | CAPE...   +14.0    LI...       +1.7
CINH...    -0.1    K Index... +20.2        | CINH...    -0.0    K Index...  +9.0
                                           |
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 -59.4 -74.9  195  30 15   1.3   0.7 | -58.7 -73.7  200  28 15   1.1   0.6
 45000 -56.8 -70.2  200  41 21   3.9   2.2 | -56.4 -69.5  200  38 19   4.0   2.2
 40000 -50.9 -59.6  195  43 22   3.8   2.1 | -50.5 -58.9  200  43 22   3.9   2.2
 38000 -48.1 -54.6  190  45 23   4.9   2.7 | -48.0 -54.4  200  44 23   4.2   2.3
 36000 -45.1 -49.2  190  47 24   4.9   2.7 | -45.1 -49.2  200  46 24   4.2   2.3
 34000 -41.4 -42.5  190  48 25   6.0   3.3 | -42.3 -44.1  200  46 23   5.1   2.8
 32000 -37.8 -36.0  185  48 25   6.0   3.3 | -39.3 -38.7  200  44 22   5.1   2.8
 30000 -34.4 -29.9  185  47 24   5.4   3.0 | -36.1 -33.0  200  42 21   5.8   3.2
 29000 -32.8 -27.0  185  45 23   5.4   3.0 | -34.3 -29.7  200  40 21   5.8   3.2
 28000 -31.1 -24.0  190  43 22   5.4   3.0 | -32.6 -26.7  205  39 20   5.8   3.2
 27000 -29.6 -21.3  190  41 21   5.0   2.8 | -30.8 -23.4  205  38 20   6.6   3.6
 26000 -28.0 -18.4  190  38 20   5.1   2.8 | -28.9 -20.0  205  37 19   6.5   3.6
 25000 -26.5 -15.7  195  35 18   5.1   2.8 | -26.9 -16.4  205  35 18   6.5   3.6
 24000 -25.0 -13.0  195  32 17   6.1   3.4 | -25.0 -13.0  205  34 18   6.8   3.7
 23000 -23.0  -9.4  195  30 15   6.7   3.7 | -22.9  -9.2  205  32 17   7.0   3.8
 22000 -21.0  -5.8  200  28 14   6.7   3.7 | -20.8  -5.4  205  30 16   7.0   3.8
 21000 -18.9  -2.0  200  25 13   6.8   3.7 | -18.7  -1.7  205  28 15   6.7   3.7
 20000 -16.9   1.6  200  24 12   6.8   3.7 | -16.2   2.8  205  26 13   6.7   3.7
 19500 -15.4   4.3  200  23 12   6.8   3.7 | -15.2   4.6  205  25 13   6.7   3.7
 19000 -14.4   6.1  200  22 11   6.8   3.7 | -14.2   6.4  205  24 12   6.7   3.7
 18500 -13.4   7.9  200  22 11   6.5   3.6 | -13.2   8.2  205  23 12   6.5   3.6
 18000 -12.5   9.5  200  21 11   6.5   3.6 | -12.2  10.0  205  22 12   6.6   3.6
 17500 -11.5  11.3  200  20 11   6.3   3.4 | -11.2  11.8  205  22 11   6.4   3.5
 17000 -10.6  12.9  200  20 10   6.1   3.4 | -10.3  13.5  205  21 11   6.2   3.4
 16500  -9.7  14.5  205  19 10   6.2   3.4 |  -9.4  15.1  205  20 10   6.2   3.4
 16000  -8.8  16.2  205  19 10   6.4   3.5 |  -8.5  16.7  205  19 10   5.9   3.2
 15500  -7.9  17.8  200  19 10   6.4   3.5 |  -7.6  18.3  205  19 10   5.9   3.3
 15000  -7.0  19.4  200  18  9   6.9   3.8 |  -6.8  19.8  205  18  9   5.6   3.1
 14500  -6.0  21.2  200  17  9   7.0   3.8 |  -6.0  21.2  200  17  9   5.7   3.1
 14000  -5.0  23.0  200  16  8   7.1   3.9 |  -5.2  22.6  200  16  8   6.2   3.4
 13500  -4.0  24.8  200  15  8   7.1   3.9 |  -4.3  24.3  200  15  8   6.5   3.6
 13000  -3.0  26.6  200  14  7   6.5   3.5 |  -3.4  25.9  195  15  7   6.8   3.7
 12500  -2.2  28.0  200  12  6   5.9   3.2 |  -2.4  27.7  195  13  7   6.9   3.8
 12000  -1.4  29.5  195  11  6   5.8   3.2 |  -1.5  29.3  195  12  6   6.1   3.3
 11500  -0.6  30.9  195  10  5   5.7   3.1 |  -0.8  30.6  195  11  6   4.9   2.7
 11000   0.3  32.5  195   9  5   5.5   3.0 |  -0.1  31.8  195  10  5   4.5   2.5
 10500   1.0  33.8  190   7  4   5.1   2.8 |   0.4  32.7  190   8  4   3.9   2.2
 10250   1.3  34.3  185   7  3   5.1   2.8 |   0.6  33.1  185   7  4   3.5   1.9
 10000   1.6  34.9  185   6  3   3.8   2.1 |   0.8  33.4  180   6  3   3.0   1.7
  9750   1.9  35.4  180   5  3   2.8   1.5 |   1.0  33.8  175   6  3   3.2   1.8
  9500   2.1  35.8  180   5  2   3.0   1.7 |   1.3  34.3  170   5  3   3.4   1.9
  9250   2.3  36.1  175   4  2   3.1   1.7 |   1.5  34.7  165   4  2   3.0   1.7
  9000   2.5  36.5  170   4  2   1.5   0.8 |   1.7  35.1  155   4  2   1.3   0.7
  8750   2.5  36.5  160   3  2  -0.2  -0.1 |   1.8  35.2  145   3  2   1.8   1.0
  8500   2.5  36.5  150   2  1  -0.5  -0.3 |   2.0  35.6  135   3  1   3.1   1.7
  8250   2.5  36.5  135   2  1   0.5   0.3 |   2.2  36.0  120   3  1   2.7   1.5
  8000   2.6  36.7  115   2  1   2.9   1.6 |   2.4  36.3  100   3  1   2.9   1.6
  7750   2.9  37.2  095   2  1   3.2   1.8 |   2.6  36.7  085   3  2   3.6   2.0
  7500   3.1  37.6  080   2  1   2.7   1.5 |   2.9  37.2  075   3  2   3.8   2.1
  7250   3.3  37.9  070   2  1   3.0   1.6 |   3.2  37.8  070   4  2   4.7   2.6
  7000   3.5  38.3  065   2  1   2.8   1.5 |   3.6  38.5  060   4  2   5.8   3.2
  6750   3.7  38.7  060   3  1   3.8   2.1 |   4.0  39.2  055   4  2   5.7   3.2
  6500   4.1  39.4  060   3  2   6.0   3.3 |   4.4  39.9  050   4  2   7.0   3.8
  6250   4.5  40.1  055   3  2   7.8   4.3 |   5.0  41.0  045   4  2   8.6   4.7
  6000   5.1  41.2  050   3  2   8.2   4.5 |   5.6  42.1  040   4  2   9.0   4.9
  5750   5.7  42.3  050   3  1   8.8   4.8 |   6.3  43.3  035   4  2   9.2   5.0
  5500   6.5  43.7  045   3  1  12.9   7.1 |   7.1  44.8  035   3  2  13.0   7.1

           09/24/2017 at 1500 MDT          |       09/24/2017 at 1800 MDT
                                           |
CAPE...   +17.1    LI...       +2.1        | CAPE...    +9.2    LI...       +0.8
CINH...    -0.3    K Index... +13.4        | CINH...    -0.1    K Index... +15.1
                                           |
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 -58.9 -74.0  205  27 14   1.2   0.6 | -58.9 -74.0  210  25 13   1.1   0.6
 45000 -56.6 -69.9  205  36 18   3.6   2.0 | -56.7 -70.1  210  33 17   3.7   2.0
 40000 -51.2 -60.2  205  41 21   3.6   1.9 | -51.2 -60.2  205  39 20   3.7   2.0
 38000 -48.9 -56.0  205  43 22   4.0   2.2 | -49.0 -56.2  205  42 21   3.6   2.0
 36000 -46.2 -51.2  205  45 23   4.0   2.2 | -46.8 -52.2  205  44 23   3.6   2.0
 34000 -43.3 -45.9  210  46 24   5.7   3.2 | -43.7 -46.7  210  45 23   5.8   3.2
 32000 -39.9 -39.8  210  47 24   5.8   3.2 | -40.3 -40.5  210  46 24   5.8   3.2
 30000 -36.1 -33.0  210  47 24   7.0   3.8 | -36.4 -33.5  210  46 24   7.2   3.9
 29000 -34.0 -29.2  210  46 24   7.0   3.8 | -34.3 -29.7  210  45 23   7.2   3.9
 28000 -31.9 -25.4  210  46 24   7.0   3.8 | -32.1 -25.8  210  45 23   7.2   3.9
 27000 -29.8 -21.6  210  45 23   7.1   3.9 | -30.0 -22.0  210  44 23   7.2   4.0
 26000 -27.6 -17.7  210  44 22   7.1   3.9 | -27.8 -18.0  210  43 22   7.2   4.0
 25000 -25.5 -13.9  210  42 22   7.1   3.9 | -25.7 -14.3  210  41 21   7.2   4.0
 24000 -23.4 -10.1  210  41 21   7.1   3.9 | -23.5 -10.3  210  40 21   6.8   3.7
 23000 -21.2  -6.2  210  39 20   7.1   3.9 | -21.6  -6.9  210  38 20   6.6   3.6
 22000 -19.1  -2.4  210  37 19   7.2   3.9 | -19.6  -3.3  210  36 18   6.6   3.6
 21000 -17.0   1.4  210  35 18   6.0   3.3 | -17.7   0.1  210  34 17   5.6   3.1
 20000 -14.8   5.4  210  32 17   6.0   3.3 | -16.0   3.2  215  31 16   5.6   3.1
 19500 -13.9   7.0  210  31 16   6.0   3.3 | -14.8   5.4  215  29 15   5.6   3.1
 19000 -13.0   8.6  210  30 15   6.0   3.3 | -13.9   7.0  215  28 14   5.6   3.1
 18500 -12.2  10.0  210  29 15   4.7   2.6 | -13.1   8.4  215  26 14   5.3   2.9
 18000 -11.5  11.3  210  27 14   4.9   2.7 | -12.4   9.7  215  25 13   5.3   2.9
 17500 -10.8  12.6  215  26 13   5.3   2.9 | -11.6  11.1  220  24 12   5.8   3.2
 17000 -10.0  14.0  215  24 13   5.6   3.1 | -10.7  12.7  220  23 12   6.1   3.4
 16500  -9.1  15.6  215  23 12   5.7   3.1 |  -9.8  14.4  215  22 11   6.3   3.5
 16000  -8.3  17.1  210  22 11   5.7   3.1 |  -8.8  16.2  215  21 11   7.4   4.0
 15500  -7.5  18.5  210  21 11   5.7   3.1 |  -7.7  18.1  215  20 10   7.3   4.0
 15000  -6.7  19.9  210  19 10   6.0   3.3 |  -6.6  20.1  215  20 10   7.7   4.2
 14500  -5.8  21.6  210  18  9   6.0   3.3 |  -5.5  22.1  210  19 10   7.8   4.3
 14000  -5.0  23.0  205  17  9   6.3   3.4 |  -4.4  24.1  210  18  9   7.3   4.0
 13500  -4.1  24.6  205  16  8   6.4   3.5 |  -3.4  25.9  205  17  9   7.2   3.9
 13000  -3.2  26.2  200  14  7   6.6   3.6 |  -2.4  27.7  200  16  8   6.6   3.6
 12500  -2.3  27.9  195  13  7   6.8   3.7 |  -1.6  29.1  200  14  7   6.1   3.4
 12000  -1.3  29.7  190  12  6   6.3   3.5 |  -0.7  30.7  195  13  7   5.5   3.0
 11500  -0.5  31.1  185  11  6   5.5   3.0 |  -0.1  31.8  190  12  6   4.7   2.6
 11000   0.2  32.4  180  10  5   4.8   2.6 |   0.5  32.9  185  10  5   4.1   2.3
 10500   0.7  33.3  175   8  4   3.7   2.0 |   1.0  33.8  180   9  5   3.9   2.1
 10250   1.0  33.8  175   8  4   3.7   2.0 |   1.2  34.2  175   8  4   1.1   0.6
 10000   1.2  34.2  170   7  4   2.8   1.5 |   1.2  34.2  170   7  4   1.7   0.9
  9750   1.4  34.5  165   6  3   2.1   1.2 |   1.5  34.7  165   7  3   4.9   2.7
  9500   1.5  34.7  160   5  3   2.3   1.3 |   1.8  35.2  165   6  3   4.1   2.3
  9250   1.7  35.1  155   5  2   2.2   1.2 |   2.1  35.8  160   5  3   4.0   2.2
  9000   1.9  35.4  145   4  2   2.0   1.1 |   2.3  36.1  150   5  2   2.3   1.2
  8750   2.0  35.6  135   4  2   2.3   1.3 |   2.5  36.5  145   4  2   2.2   1.2
  8500   2.2  36.0  120   3  2   2.5   1.4 |   2.7  36.9  135   3  2   3.2   1.8
  8250   2.4  36.3  105   3  2   2.6   1.4 |   2.9  37.2  125   3  2   2.4   1.3
  8000   2.6  36.7  090   3  2   3.1   1.7 |   3.0  37.4  110   3  1   1.3   0.7
  7750   2.8  37.0  080   4  2   4.5   2.4 |   3.2  37.8  090   3  1   2.8   1.5
  7500   3.2  37.8  070   4  2   4.6   2.5 |   3.4  38.1  080   3  2   3.4   1.9
  7250   3.6  38.5  065   4  2   6.5   3.6 |   3.7  38.7  070   3  2   5.1   2.8
  7000   4.2  39.6  060   5  2   8.9   4.9 |   4.2  39.6  060   4  2   7.3   4.0
  6750   4.7  40.5  055   5  2   7.3   4.0 |   4.6  40.3  050   4  2   6.5   3.6
  6500   5.2  41.4  050   4  2   7.4   4.0 |   5.1  41.2  045   4  2   7.3   4.0
  6250   5.9  42.6  050   4  2   9.2   5.1 |   5.7  42.3  040   4  2   8.6   4.7
  6000   6.5  43.7  045   4  2   9.6   5.3 |   6.4  43.5  035   4  2   9.1   5.0
  5750   7.2  45.0  045   4  2   9.7   5.3 |   7.0  44.6  030   4  2   8.8   4.8
  5500   8.0  46.4  040   4  2  13.1   7.2 |   7.7  45.9  030   3  2  10.6   5.8
________________________________________________________________________________

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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