Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231310
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0710 MDT Friday, September 23, 2016

This forecast is for Friday, September 23, 2016:

If the trigger temperature of 76.8 F/24.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 707 ft/min (3.6 m/s)
   Maximum height of thermals.................. 13868 ft MSL (8535 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10494 ft MSL (5161 ft AGL)
Thermal soaring outlook for Saturday 09/24..... Good

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)................ Neither
Potential height of wave....................... 46394 ft MSL (41061 ft AGL)
Wave soaring outlook for Saturday 09/24........ Good

Remarks... Strong southerly flow at low and mid levels today...ahead of a deep
           upper trough over utah.

Sunrise/Sunset.................... 06:48:50 / 18:54:23 MDT
Total possible sunshine........... 12 hr 5 min 33 sec (725 min 33 sec)
Altitude of sun at 12:51:37 MDT... 49.72 degrees

Upper air data from numerical model forecast valid on 09/23/2016 at 0600 MDT

Freezing level.................. 15444 ft MSL (10111 ft AGL)
Convective condensation level... 15636 ft MSL (10303 ft AGL)
Lifted condensation level....... 15073 ft MSL (9740 ft AGL)
Lifted index.................... -0.9
K index......................... +15.7

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  -65.1 -85.2   200   25   13   0.8   0.5      M     M       M      M    M
 45000  -61.6 -78.9   200   34   17   6.3   3.4      M     M       M      M    M
 40000  -52.1 -61.8   190   33   17   6.9   3.8      M     M       M      M    M
 38000  -48.0 -54.4   190   34   18   6.9   3.8      M     M       M      M    M
 36000  -43.9 -47.0   195   35   18   6.9   3.8      M     M       M      M    M
 34000  -39.7 -39.5   195   35   18   7.0   3.9      M     M       M      M    M
 32000  -35.0 -31.0   195   34   18   7.1   3.9      M     M       M      M    M
 30000  -30.6 -23.1   195   32   17   7.4   4.0   45.3 113.5    12.4      M    M
 29000  -28.4 -19.1   195   31   16   7.4   4.0   44.4 111.9    11.9      M    M
 28000  -26.2 -15.2   195   30   16   7.4   4.0   43.6 110.5    11.4      M    M
 27000  -24.0 -11.2   195   30   15   7.2   3.9   42.5 108.5    10.7      M    M
 26000  -21.9  -7.4   195   29   15   7.2   3.9   41.5 106.7    10.0      M    M
 25000  -19.7  -3.5   195   28   14   7.2   3.9   40.6 105.1     9.4      M    M
 24000  -17.6   0.3   190   27   14   7.0   3.8   39.6 103.3     8.7      M    M
 23000  -15.5   4.1   190   26   14   7.0   3.8   38.6 101.5     7.9      M    M
 22000  -13.5   7.7   190   26   13   7.0   3.9   37.7  99.8     7.2      M    M
 21000  -11.4  11.5   190   25   13   6.9   3.8   36.6  98.0     6.4      M    M
 20000   -9.4  15.1   190   24   13   6.9   3.8   35.6  96.1     5.6      M    M
 19500   -8.3  17.1   190   24   12   6.9   3.8   35.1  95.2     5.2      M    M
 19000   -7.3  18.9   195   24   12   6.8   3.7   34.7  94.4     4.8      M    M
 18500   -6.3  20.7   195   23   12   6.7   3.7   34.1  93.5     4.4      M    M
 18000   -5.4  22.3   195   23   12   6.7   3.7   33.6  92.5     3.9      M    M
 17500   -3.9  25.0   195   22   12   6.9   3.8   32.9  91.2     3.2      M    M
 17000   -2.9  26.8   195   22   11   7.0   3.8   32.4  90.3     2.8      M    M
 16500   -1.9  28.6   195   21   11   6.8   3.7   31.9  89.4     2.3      M    M
 16000   -0.9  30.4   200   21   11   6.9   3.8   31.4  88.5     1.8      M    M
 15500    0.1  32.2   200   20   11   7.0   3.8   30.9  87.7     1.4      M    M
 15000    1.1  34.0   200   20   10   7.1   3.9   30.5  86.9     0.9      M    M
 14500    2.1  35.8   200   20   10   7.1   3.9   30.0  86.1     0.5      M    M
 14000    3.1  37.6   205   19   10   6.9   3.8   29.6  85.3     0.1      M    M
 13500    4.1  39.4   205   19   10   6.9   3.8   29.1  84.4    -0.4    668  3.4
 13000    5.2  41.4   210   19   10   7.4   4.1   28.7  83.7    -0.8    623  3.2
 12500    6.2  43.2   210   19   10   7.5   4.1   28.3  83.0    -1.2    575  2.9
 12000    7.3  45.1   215   20   10   7.0   3.8   27.9  82.3    -1.6    528  2.7
 11500    8.3  46.9   215   19   10   6.9   3.8   27.5  81.4    -2.1    484  2.5
 11000    9.3  48.7   215   19   10   6.9   3.8   27.0  80.6    -2.5    439  2.2
 10500   10.3  50.5   220   19   10   6.9   3.8   26.6  79.9    -3.0    394  2.0
 10250   10.8  51.4   220   19   10   7.6   4.2   26.4  79.5    -3.2    371  1.9
 10000   11.4  52.5   220   18    9   8.1   4.4   26.2  79.2    -3.4    346  1.8
  9750   12.0  53.6   220   18    9   7.7   4.2   26.1  79.0    -3.5    322  1.6
  9500   12.5  54.5   220   17    9   7.8   4.3   25.9  78.7    -3.7    298  1.5
  9250   13.1  55.6   220   16    8   7.9   4.4   25.8  78.4    -3.9    274  1.4
  9000   13.7  56.7   215   16    8   8.2   4.5   25.7  78.2    -4.1    249  1.3
  8750   14.2  57.6   215   15    8   8.2   4.5   25.5  78.0    -4.2    225  1.1
  8500   14.8  58.6   215   15    8   8.2   4.5   25.4  77.7    -4.4    200  1.0
  8250   15.4  59.7   210   14    7   8.2   4.5   25.3  77.5    -4.6    176  0.9
  8000   15.9  60.6   210   14    7   7.6   4.2   25.2  77.3    -4.8    151  0.8
  7750   16.4  61.5   205   13    7   7.0   3.8   25.0  76.9    -5.0    129  0.7
  7500   16.9  62.4   205   13    7   7.3   4.0   24.8  76.6    -5.3    107  0.5
  7250   17.4  63.3   200   12    6   6.2   3.4   24.6  76.2    -5.5     85  0.4
  7000   17.8  64.0   200   11    6   4.4   2.4   24.2  75.6    -5.9     67  0.3
  6750   18.0  64.4   200   11    6   2.6   1.4   23.7  74.7    -6.4     53  0.3
  6500   18.1  64.6   195   10    5   1.1   0.6   23.1  73.6    -7.0     43  0.2
  6250   18.1  64.6   195    9    5  -2.4  -1.3   22.4  72.3    -7.8     36  0.2
  6000   17.7  63.9   190    8    4  -4.9  -2.7   21.3  70.4    -9.0     40  0.2
  5750   17.3  63.1   190    7    4  -5.5  -3.0   20.2  68.4   -10.1     45  0.2
  5500   16.4  61.5   190    5    3 -17.6  -9.7   18.7  65.7   -11.7     63  0.3

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

           09/23/2016 at 0900 MDT          |       09/23/2016 at 1200 MDT
                                           |
CAPE...    +1.9    LI...       +1.7        | CAPE...    +1.9    LI...       +1.8
CINH...   -30.8    K Index... +11.3        | CINH...   -12.0    K Index... +15.4
                                           |
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 -64.3 -83.7  195  24 13   1.1   0.6 | -63.7 -82.7  190  27 14   1.6   0.9
 45000 -60.5 -76.9  195  37 19   6.2   3.4 | -59.5 -75.1  190  40 21   6.1   3.3
 40000 -51.2 -60.2  190  40 21   6.0   3.3 | -50.5 -58.9  180  46 24   5.0   2.8
 38000 -47.6 -53.7  190  40 21   6.0   3.3 | -47.5 -53.5  185  46 24   5.0   2.7
 36000 -44.0 -47.2  190  41 21   6.0   3.3 | -44.5 -48.1  185  46 24   5.0   2.7
 34000 -40.2 -40.4  190  40 21   6.3   3.5 | -41.0 -41.8  190  44 23   6.2   3.4
 32000 -36.0 -32.8  190  39 20   6.4   3.5 | -36.9 -34.4  190  41 21   6.2   3.4
 30000 -31.8 -25.2  190  37 19   7.2   3.9 | -32.7 -26.9  195  39 20   7.3   4.0
 29000 -29.7 -21.5  190  36 18   7.2   3.9 | -30.6 -23.1  195  37 19   7.3   4.0
 28000 -27.5 -17.5  190  34 18   7.2   3.9 | -28.4 -19.1  195  36 18   7.2   4.0
 27000 -25.4 -13.7  190  33 17   7.2   4.0 | -26.1 -15.0  195  35 18   7.8   4.3
 26000 -23.2  -9.8  190  32 16   7.2   4.0 | -23.8 -10.8  195  34 17   7.8   4.3
 25000 -21.0  -5.8  190  31 16   7.2   4.0 | -21.5  -6.7  195  33 17   7.8   4.3
 24000 -18.9  -2.0  190  29 15   7.3   4.0 | -19.1  -2.4  195  31 16   7.7   4.2
 23000 -16.7   1.9  190  28 15   7.3   4.0 | -16.8   1.8  195  30 16   7.7   4.2
 22000 -14.5   5.9  190  27 14   7.3   4.0 | -14.5   5.9  190  29 15   7.7   4.2
 21000 -12.3   9.9  190  26 14   7.4   4.1 | -12.3   9.9  190  29 15   7.2   3.9
 20000 -10.1  13.8  190  26 13   7.5   4.1 | -10.2  13.6  190  28 15   7.2   3.9
 19500  -9.0  15.8  190  25 13   7.5   4.1 |  -9.1  15.6  190  28 14   7.2   3.9
 19000  -7.9  17.8  190  25 13   7.4   4.1 |  -8.0  17.6  190  28 14   7.1   3.9
 18500  -6.9  19.6  185  24 13   7.1   3.9 |  -7.0  19.4  190  27 14   6.9   3.8
 18000  -5.3  22.5  185  24 12   7.1   3.9 |  -6.0  21.2  190  27 14   7.0   3.8
 17500  -4.3  24.3  185  24 12   7.1   3.9 |  -4.5  23.9  190  26 13   6.1   3.4
 17000  -3.2  26.2  185  23 12   7.1   3.9 |  -3.6  25.5  195  26 13   6.2   3.4
 16500  -2.2  28.0  190  23 12   7.1   3.9 |  -2.7  27.1  195  25 13   5.7   3.1
 16000  -1.1  30.0  190  23 12   7.1   3.9 |  -2.0  28.4  195  24 12   5.6   3.1
 15500  -0.1  31.8  190  22 12   7.1   3.9 |  -1.2  29.8  195  23 12   5.7   3.1
 15000   1.0  33.8  190  22 11   7.0   3.9 |  -0.4  31.3  195  22 12   5.8   3.2
 14500   2.0  35.6  195  22 11   7.0   3.9 |   0.4  32.7  195  21 11   5.7   3.1
 14000   3.0  37.4  195  22 11   6.6   3.6 |   1.4  34.5  195  20 11   7.0   3.8
 13500   4.0  39.2  200  22 12   6.7   3.7 |   2.4  36.3  200  20 10   6.8   3.7
 13000   5.0  41.0  200  22 12   5.8   3.2 |   3.4  38.1  195  19 10   7.4   4.1
 12500   5.8  42.4  205  22 11   5.8   3.2 |   4.4  39.9  195  17  9   7.4   4.1
 12000   6.7  44.1  205  22 11   6.3   3.4 |   5.5  41.9  195  16  8   8.3   4.5
 11500   7.5  45.5  205  21 11   6.4   3.5 |   6.7  44.1  195  15  8   8.5   4.7
 11000   8.4  47.1  210  20 10   6.6   3.6 |   7.9  46.2  190  13  7   8.8   4.8
 10500   9.4  48.9  210  19 10   6.6   3.6 |   9.2  48.6  190  13  6   8.9   4.9
 10250   9.8  49.6  210  19 10   7.1   3.9 |   9.9  49.8  190  12  6  10.5   5.7
 10000  10.3  50.5  210  18  9   7.3   4.0 |  10.7  51.3  190  12  6  10.9   6.0
  9750  10.8  51.4  210  17  9   7.0   3.8 |  11.4  52.5  190  12  6   9.9   5.4
  9500  11.3  52.3  210  17  9   7.0   3.9 |  12.2  54.0  190  12  6  10.5   5.8
  9250  11.8  53.2  210  16  8   7.2   3.9 |  13.0  55.4  190  12  6   9.0   5.0
  9000  12.4  54.3  210  16  8   7.5   4.1 |  13.6  56.5  190  11  6   8.9   4.9
  8750  12.9  55.2  210  16  8   7.6   4.2 |  14.3  57.7  190  11  6  10.1   5.5
  8500  13.4  56.1  210  15  8   7.5   4.1 |  15.0  59.0  190  11  6  10.0   5.5
  8250  14.0  57.2  210  14  7   7.9   4.3 |  15.8  60.4  190  11  6   9.2   5.1
  8000  14.6  58.3  210  14  7   8.1   4.5 |  16.4  61.5  190  11  6   9.4   5.1
  7750  15.1  59.2  210  13  7   7.8   4.3 |  17.2  63.0  190  11  5  10.5   5.7
  7500  15.7  60.3  205  12  6   8.2   4.5 |  18.0  64.4  190  10  5  10.6   5.8
  7250  16.3  61.3  205  12  6   6.7   3.7 |  18.7  65.7  190  10  5   9.7   5.3
  7000  16.6  61.9  205  11  6   5.0   2.8 |  19.4  66.9  190  10  5   9.1   5.0
  6750  17.0  62.6  200  11  6   5.6   3.1 |  20.2  68.4  190  10  5  10.4   5.7
  6500  17.4  63.3  200  10  5   5.6   3.1 |  21.0  69.8  190  10  5  11.0   6.0
  6250  17.7  63.9  195   9  4   4.7   2.6 |  21.8  71.2  190   9  5  10.8   6.0
  6000  18.0  64.4  195   8  4   4.4   2.4 |  22.6  72.7  190   9  5  11.4   6.3
  5750  18.3  64.9  195   7  3   4.0   2.2 |  23.4  74.1  190   9  5   9.7   5.3
  5500  18.6  65.5  190   5  3   7.1   3.9 |  24.2  75.6  190   8  4  14.8   8.1

           09/23/2016 at 1500 MDT          |       09/23/2016 at 1800 MDT
                                           |
CAPE...   +49.3    LI...       -0.4        | CAPE...   +21.2    LI...       -0.8
CINH...    -3.8    K Index... +26.1        | CINH...   -16.6    K Index... +22.6
                                           |
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 -62.4 -80.3  195  29 15   1.1   0.6 | -61.2 -78.2  200  24 12   1.3   0.7
 45000 -59.2 -74.6  190  45 23   5.2   2.9 | -58.1 -72.6  190  40 21   4.2   2.3
 40000 -51.3 -60.3  180  50 26   5.0   2.8 | -51.8 -61.2  180  50 26   4.5   2.5
 38000 -48.4 -55.1  185  48 25   5.0   2.7 | -49.0 -56.2  185  48 25   4.7   2.6
 36000 -45.4 -49.7  185  47 24   5.0   2.7 | -46.1 -51.0  185  46 24   4.7   2.6
 34000 -41.9 -43.4  190  44 23   6.4   3.5 | -42.6 -44.7  190  44 23   6.7   3.7
 32000 -37.5 -35.5  195  41 21   6.5   3.5 | -38.1 -36.6  190  43 22   6.7   3.7
 30000 -33.1 -27.6  195  40 20   8.0   4.4 | -33.8 -28.8  190  41 21   7.5   4.1
 29000 -30.7 -23.3  200  39 20   8.0   4.4 | -31.6 -24.9  190  40 20   7.5   4.1
 28000 -28.3 -18.9  200  39 20   8.0   4.4 | -29.3 -20.7  190  38 20   7.5   4.1
 27000 -26.0 -14.8  200  38 20   7.6   4.2 | -27.1 -16.8  190  37 19   7.4   4.0
 26000 -23.7 -10.7  200  37 19   7.6   4.2 | -24.9 -12.8  190  36 18   7.4   4.0
 25000 -21.5  -6.7  195  36 18   7.6   4.1 | -22.7  -8.9  190  35 18   7.3   4.0
 24000 -19.3  -2.7  195  35 18   7.3   4.0 | -20.6  -5.1  185  33 17   6.4   3.5
 23000 -17.1   1.2  195  33 17   7.3   4.0 | -18.7  -1.7  190  32 16   6.4   3.5
 22000 -14.9   5.2  190  31 16   7.2   4.0 | -16.8   1.8  190  31 16   6.4   3.5
 21000 -13.0   8.6  190  30 16   5.5   3.0 | -15.0   5.0  190  29 15   5.8   3.2
 20000 -11.4  11.5  195  29 15   5.5   3.0 | -13.4   7.9  185  26 13   5.8   3.2
 19500 -10.6  12.9  195  29 15   5.5   3.0 | -12.5   9.5  185  24 13   5.8   3.2
 19000  -9.8  14.4  195  29 15   5.6   3.1 | -11.7  10.9  185  23 12   5.7   3.1
 18500  -9.0  15.8  200  28 14   5.1   2.8 | -10.7  12.7  185  22 11   7.9   4.4
 18000  -8.3  17.1  200  26 13   5.2   2.9 |  -9.5  14.9  180  21 11   7.8   4.3
 17500  -7.2  19.0  200  24 12   6.4   3.5 |  -8.4  16.9  180  20 10   8.2   4.5
 17000  -6.3  20.7  195  22 11   6.3   3.5 |  -6.5  20.3  180  18  9   8.6   4.7
 16500  -5.4  22.3  195  20 10   7.7   4.2 |  -5.3  22.5  180  18  9   8.6   4.7
 16000  -4.2  24.4  195  19 10   8.3   4.6 |  -4.0  24.8  180  17  9   8.6   4.7
 15500  -3.0  26.6  190  17  9   8.7   4.8 |  -2.8  27.0  180  16  8   8.6   4.7
 15000  -1.6  29.1  190  17  9   9.6   5.2 |  -1.5  29.3  180  16  8   8.7   4.8
 14500  -0.2  31.6  190  16  8   9.5   5.2 |  -0.2  31.6  180  15  8   8.7   4.8
 14000   1.2  34.2  190  16  8   9.5   5.2 |   1.1  34.0  185  15  8   8.9   4.9
 13500   2.6  36.7  185  15  8   9.5   5.2 |   2.4  36.3  185  15  7   8.9   4.9
 13000   4.0  39.2  185  15  8   9.7   5.3 |   3.7  38.7  190  14  7   8.7   4.8
 12500   5.4  41.7  185  15  8   9.7   5.3 |   5.0  41.0  190  14  7   8.7   4.8
 12000   6.9  44.4  185  15  8   9.8   5.3 |   6.3  43.3  195  14  7   8.9   4.9
 11500   8.3  46.9  185  14  7   9.8   5.4 |   7.6  45.7  200  13  7   8.9   4.9
 11000   9.8  49.6  185  14  7   9.3   5.1 |   8.9  48.0  200  13  7   8.5   4.7
 10500  11.1  52.0  185  14  7   9.3   5.1 |  10.1  50.2  205  13  7   8.4   4.6
 10250  11.9  53.4  185  14  7  11.0   6.0 |  10.8  51.4  205  13  7  10.2   5.6
 10000  12.7  54.9  185  14  7  11.2   6.1 |  11.6  52.9  205  13  7  10.6   5.8
  9750  13.5  56.3  185  14  7  10.3   5.6 |  12.3  54.1  210  13  7   9.5   5.2
  9500  14.3  57.7  185  14  7  11.0   6.1 |  13.1  55.6  210  13  7  10.1   5.5
  9250  15.1  59.2  185  14  7   8.9   4.9 |  13.8  56.8  210  13  7   8.8   4.8
  9000  15.7  60.3  185  14  7   8.4   4.6 |  14.4  57.9  210  13  6   8.6   4.7
  8750  16.4  61.5  185  13  7  10.2   5.6 |  15.1  59.2  215  12  6   9.5   5.2
  8500  17.1  62.8  185  13  7   9.8   5.4 |  15.8  60.4  215  12  6   9.5   5.2
  8250  17.9  64.2  185  13  7   9.6   5.3 |  16.5  61.7  215  12  6   8.5   4.6
  8000  18.6  65.5  185  13  7   9.7   5.3 |  17.1  62.8  220  12  6   8.6   4.7
  7750  19.3  66.7  185  13  7  10.0   5.5 |  17.8  64.0  220  12  6   9.9   5.4
  7500  20.1  68.2  185  13  7   9.9   5.5 |  18.5  65.3  220  12  6   9.9   5.4
  7250  20.8  69.4  185  13  7   9.8   5.4 |  19.3  66.7  225  11  6   9.3   5.1
  7000  21.5  70.7  185  13  7   9.8   5.4 |  19.9  67.8  225  11  6   8.7   4.8
  6750  22.3  72.1  185  13  6  10.2   5.6 |  20.6  69.1  225  11  6   9.8   5.4
  6500  23.0  73.4  185  12  6  10.2   5.6 |  21.4  70.5  225  11  6  10.3   5.7
  6250  23.8  74.8  185  12  6  10.9   6.0 |  22.1  71.8  230  10  5  10.0   5.5
  6000  24.7  76.5  185  12  6  12.1   6.7 |  22.8  73.0  230  10  5  10.0   5.5
  5750  25.5  77.9  190  11  6   9.8   5.4 |  23.6  74.5  230  10  5   9.3   5.1
  5500  26.3  79.3  185  10  5  13.3   7.3 |  24.2  75.6  230   9  4   9.4   5.2
________________________________________________________________________________

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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