Soaring Guidance
Issued by NWS Denver/Boulder, CO

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262
UXUS97 KBOU 230127
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1927 MDT Thursday, September 22, 2016

This forecast is for Friday, September 23, 2016:

If the trigger temperature of 75.9 F/24.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 435 ft/min (2.2 m/s)
   Maximum height of thermals.................. 13213 ft MSL (7906 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10680 ft MSL (5373 ft AGL)
Thermal soaring outlook for Saturday 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)................ Neither
Potential height of wave....................... 15868 ft MSL (10561 ft AGL)
Wave soaring outlook for Saturday 09/24........ Poor

Remarks...

Sunrise/Sunset.................... 06:48:34 / 18:55:34 MDT
Total possible sunshine........... 12 hr 7 min 1 sec (727 min 1 sec)
Altitude of sun at 12:51:34 MDT... 49.77 degrees

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

Freezing level.................. 15919 ft MSL (10612 ft AGL)
Convective condensation level... 14163 ft MSL (8856 ft AGL)
Lifted condensation level....... 13669 ft MSL (8362 ft AGL)
Lifted index.................... -2.5
K index......................... -7.8

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  -65.8 -86.4   210   53   27   1.5   0.8      M     M       M      M    M
 45000  -62.1 -79.8   200   67   35   5.7   3.1      M     M       M      M    M
 40000  -52.9 -63.2   200   64   33   7.8   4.3      M     M       M      M    M
 38000  -48.3 -54.9   200   67   34   7.7   4.2      M     M       M      M    M
 36000  -43.7 -46.7   205   70   36   7.7   4.2      M     M       M      M    M
 34000  -39.5 -39.1   205   71   36   6.8   3.7      M     M       M      M    M
 32000  -35.4 -31.7   205   71   37   6.8   3.7      M     M       M      M    M
 30000  -31.1 -24.0   205   69   35   7.4   4.1   45.4 113.8    13.0      M    M
 29000  -28.3 -18.9   205   66   34   7.4   4.1   44.3 111.8    12.3      M    M
 28000  -26.1 -15.0   205   64   33   7.4   4.1   43.6 110.4    11.9      M    M
 27000  -23.8 -10.8   205   62   32   7.4   4.1   42.6 108.7    11.3      M    M
 26000  -21.6  -6.9   205   60   31   7.4   4.1   41.7 107.0    10.7      M    M
 25000  -19.4  -2.9   205   58   30   7.5   4.1   40.9 105.7    10.2      M    M
 24000  -17.3   0.9   200   55   28   6.6   3.6   39.9 103.8     9.4      M    M
 23000  -15.3   4.5   200   52   27   6.6   3.6   38.7 101.6     8.5      M    M
 22000  -13.4   7.9   200   49   25   6.7   3.7   37.6  99.7     7.7      M    M
 21000  -11.5  11.3   195   46   24   6.2   3.4   36.4  97.5     6.7      M    M
 20000   -9.7  14.5   190   45   23   6.4   3.5   35.1  95.2     5.7      M    M
 19500   -8.8  16.2   185   44   23   6.6   3.6   34.6  94.2     5.1      M    M
 19000   -7.9  17.8   185   44   23   7.2   3.9   34.1  93.3     4.7      M    M
 18500   -6.7  19.9   185   43   22   8.4   4.6   33.8  92.8     4.4      M    M
 18000   -5.4  22.3   180   43   22   8.4   4.6   33.6  92.4     4.3      M    M
 17500   -4.1  24.6   180   42   22   8.3   4.5   33.3  92.0     4.1      M    M
 17000   -2.8  27.0   185   42   22   8.4   4.6   33.1  91.6     4.0      M    M
 16500   -1.5  29.3   185   42   22   8.0   4.4   32.9  91.2     3.9      M    M
 16000   -0.4  31.3   190   42   22   6.6   3.6   32.4  90.3     3.6      M    M
 15500    0.6  33.1   190   43   22   6.8   3.7   31.9  89.4     3.2      M    M
 15000    2.0  35.6   195   43   22   5.8   3.2   31.0  87.7     2.3      M    M
 14500    2.8  37.0   200   43   22   5.7   3.1   30.3  86.6     1.7      M    M
 14000    3.6  38.5   200   44   23   5.0   2.7   29.6  85.2     1.0      M    M
 13500    4.3  39.7   205   45   23   5.2   2.8   28.8  83.9     0.3      M    M
 13000    5.0  41.0   205   46   24   5.0   2.7   28.1  82.5    -0.5    615  3.1
 12500    5.6  42.1   210   46   24   5.2   2.8   27.3  81.1    -1.3    581  3.0
 12000    6.4  43.5   210   46   24   7.9   4.3   26.8  80.2    -2.0    542  2.8
 11500    7.5  45.5   210   45   23   8.3   4.6   26.5  79.7    -2.4    494  2.5
 11000    8.6  47.5   210   43   22   7.5   4.1   26.2  79.2    -2.7    447  2.3
 10500    9.6  49.3   210   42   22   7.1   3.9   25.8  78.5    -3.2    401  2.0
 10250   10.2  50.4   210   41   21  11.2   6.2   25.7  78.3    -3.3    376  1.9
 10000   11.1  52.0   210   39   20  10.7   5.9   26.0  78.7    -3.2    342  1.7
  9750   11.6  52.9   210   39   20   7.0   3.8   25.8  78.4    -3.4    319  1.6
  9500   12.2  54.0   210   38   19   8.2   4.5   25.6  78.2    -3.6    296  1.5
  9250   12.7  54.9   210   37   19   7.4   4.1   25.5  77.9    -3.8    273  1.4
  9000   13.1  55.6   210   36   18   7.8   4.3   25.3  77.6    -4.1    251  1.3
  8750   13.7  56.7   210   35   18   8.5   4.7   25.2  77.4    -4.3    226  1.2
  8500   14.3  57.7   210   33   17   8.3   4.5   25.1  77.2    -4.4    202  1.0
  8250   14.9  58.8   210   32   17   8.6   4.7   25.0  77.0    -4.6    177  0.9
  8000   15.4  59.7   210   30   16   7.2   3.9   24.9  76.8    -4.8    153  0.8
  7750   15.8  60.4   210   29   15   5.5   3.0   24.6  76.3    -5.1    134  0.7
  7500   16.2  61.2   210   27   14   5.3   2.9   24.3  75.7    -5.5    116  0.6
  7250   16.5  61.7   210   26   13   6.3   3.4   24.0  75.1    -5.9     98  0.5
  7000   17.0  62.6   205   23   12   6.8   3.7   23.7  74.7    -6.2     77  0.4
  6750   17.4  63.3   205   21   11   5.6   3.1   23.5  74.2    -6.5     57  0.3
  6500   17.8  64.0   200   20   10   4.5   2.5   23.1  73.6    -6.8     38  0.2
  6250   18.0  64.4   200   18    9   0.9   0.5   22.6  72.7    -7.4     24  0.1
  6000   17.9  64.2   195   17    9  -0.7  -0.4   21.8  71.3    -8.2     19  0.1
  5750   17.8  64.0   190   16    8  -6.5  -3.6   20.9  69.7    -9.1     17  0.1
  5500   16.6  61.9   185   14    7 -22.9 -12.6   19.1  66.4   -11.0     43  0.2

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

           09/23/2016 at 0900 MDT          |       09/23/2016 at 1200 MDT
                                           |
K index... -5.8  LI... -0.6                | K index... +24.2  LI... +1.0
CAPE... +89.0  CIN... -157.8               | CAPE... 0.0  CIN... M
                                           |
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 -65.0 -85.0  210  50 26   1.2   0.7 | -63.5 -82.3  200  50 26   1.3   0.7
 45000 -61.4 -78.5  200  76 39   6.5   3.5 | -60.1 -76.2  195  77 39   5.9   3.2
 40000 -51.3 -60.3  195  81 42   5.4   3.0 | -50.9 -59.6  190  90 46   4.6   2.5
 38000 -48.0 -54.4  200  81 42   5.5   3.0 | -48.2 -54.8  195  87 45   4.7   2.6
 36000 -44.7 -48.5  200  81 42   5.5   3.0 | -45.4 -49.7  200  85 44   4.7   2.6
 34000 -40.8 -41.4  200  78 40   7.0   3.8 | -41.6 -42.9  200  79 41   7.0   3.9
 32000 -36.6 -33.9  205  73 37   7.0   3.8 | -37.4 -35.3  200  72 37   7.0   3.9
 30000 -32.2 -26.0  205  69 36   7.6   4.2 | -32.7 -26.9  205  68 35   8.5   4.6
 29000 -29.4 -20.9  205  67 35   7.6   4.2 | -29.5 -21.1  205  68 35   8.5   4.7
 28000 -27.1 -16.8  205  66 34   7.6   4.2 | -27.0 -16.6  210  67 35   8.6   4.7
 27000 -24.9 -12.8  200  63 32   7.4   4.1 | -24.7 -12.5  205  66 34   7.5   4.1
 26000 -22.6  -8.7  200  59 30   7.4   4.1 | -22.5  -8.5  200  65 34   7.5   4.1
 25000 -20.4  -4.7  195  55 28   7.4   4.1 | -20.2  -4.4  195  64 33   7.5   4.1
 24000 -18.2  -0.8  195  53 27   7.0   3.8 | -18.2  -0.8  195  62 32   5.9   3.3
 23000 -16.1   3.0  195  53 27   7.0   3.8 | -16.5   2.3  195  58 30   5.9   3.2
 22000 -14.0   6.8  190  53 27   7.0   3.8 | -14.7   5.5  195  53 27   5.9   3.2
 21000 -12.0  10.4  190  51 26   6.5   3.6 | -12.7   9.1  195  50 26   7.5   4.1
 20000 -10.1  13.8  185  48 25   6.5   3.6 | -10.4  13.3  190  47 24   7.6   4.2
 19500  -9.1  15.6  185  47 24   6.5   3.6 |  -9.3  15.3  190  45 23   7.7   4.2
 19000  -8.2  17.2  180  45 23   6.9   3.8 |  -8.2  17.2  190  44 23   7.6   4.2
 18500  -7.0  19.4  180  43 22   8.4   4.6 |  -7.2  19.0  190  43 22   7.0   3.9
 18000  -5.7  21.7  180  42 21   8.3   4.6 |  -6.2  20.8  190  42 22   7.2   4.0
 17500  -4.5  23.9  185  40 21   8.2   4.5 |  -5.2  22.6  185  42 21   6.2   3.4
 17000  -3.3  26.1  185  39 20   8.1   4.5 |  -4.4  24.1  190  40 21   5.9   3.2
 16500  -2.1  28.2  190  39 20   8.1   4.4 |  -3.6  25.5  190  39 20   6.1   3.4
 16000  -0.9  30.4  195  40 20   8.0   4.4 |  -2.7  27.1  195  40 20   7.3   4.0
 15500   0.3  32.5  200  41 21   8.1   4.5 |  -1.1  30.0  200  42 22   6.7   3.7
 15000   1.9  35.4  205  44 23   6.7   3.7 |  -0.3  31.5  205  44 23   5.4   3.0
 14500   2.9  37.2  210  46 23   6.7   3.7 |   0.6  33.1  210  47 24   5.5   3.0
 14000   3.8  38.8  210  47 24   5.7   3.1 |   1.3  34.3  215  47 24   4.0   2.2
 13500   4.6  40.3  210  47 24   5.9   3.2 |   1.9  35.4  220  44 22   4.1   2.3
 13000   5.4  41.7  215  48 25   4.9   2.7 |   2.6  36.7  220  40 21   4.8   2.6
 12500   6.2  43.2  215  48 25   5.0   2.7 |   3.3  37.9  220  34 18   4.6   2.5
 12000   6.9  44.4  215  48 25   4.4   2.4 |   4.1  39.4  220  29 15   8.0   4.4
 11500   7.5  45.5  210  48 25   4.4   2.4 |   5.3  41.5  215  26 13   8.7   4.8
 11000   8.1  46.6  210  48 25   5.1   2.8 |   6.5  43.7  210  24 12   8.1   4.4
 10500   8.8  47.8  210  46 24   4.9   2.7 |   7.6  45.7  205  22 11   7.7   4.2
 10250   9.1  48.4  210  45 23   7.9   4.3 |   8.2  46.8  205  22 11  10.4   5.7
 10000   9.7  49.5  210  44 22   8.6   4.7 |   9.0  48.2  205  21 11  11.3   6.2
  9750  10.2  50.4  210  42 21   6.4   3.5 |   9.8  49.6  205  21 11   9.6   5.3
  9500  10.6  51.1  210  40 20   7.0   3.8 |  10.5  50.9  200  21 11  10.2   5.6
  9250  11.1  52.0  205  38 19   7.3   4.0 |  11.3  52.3  200  21 11   9.5   5.2
  9000  11.6  52.9  205  36 18   7.9   4.3 |  11.9  53.4  200  21 11   9.6   5.3
  8750  12.1  53.8  205  34 18   7.9   4.4 |  12.7  54.9  200  20 10  10.3   5.7
  8500  12.7  54.9  205  33 17   7.8   4.3 |  13.5  56.3  200  20 10  10.1   5.5
  8250  13.2  55.8  205  32 16   8.5   4.6 |  14.2  57.6  205  20 10  10.4   5.7
  8000  13.8  56.8  200  30 15   8.7   4.8 |  15.0  59.0  205  20 10  10.1   5.5
  7750  14.3  57.7  200  28 15   8.1   4.4 |  15.7  60.3  205  20 10   9.7   5.3
  7500  14.9  58.8  200  27 14   8.0   4.4 |  16.4  61.5  205  20 10   9.6   5.2
  7250  15.4  59.7  195  26 13   8.4   4.6 |  17.2  63.0  205  20 10  10.2   5.6
  7000  16.0  60.8  195  25 13   8.7   4.8 |  17.9  64.2  205  19 10  10.5   5.8
  6750  16.6  61.9  195  24 12   8.5   4.7 |  18.7  65.7  205  19 10   9.4   5.2
  6500  17.2  63.0  190  23 12   7.9   4.3 |  19.4  66.9  205  19 10   9.4   5.1
  6250  17.6  63.7  190  21 11   4.9   2.7 |  20.1  68.2  205  18 10  11.1   6.1
  6000  17.8  64.0  185  18  9   3.3   1.8 |  21.0  69.8  205  18  9  12.4   6.8
  5750  18.0  64.4  180  15  8   3.5   1.9 |  21.9  71.4  205  17  9  10.1   5.5
  5500  18.3  64.9  175  11  5   5.9   3.2 |  22.7  72.9  205  16  8  13.8   7.6

           09/23/2016 at 1500 MDT          |       09/23/2016 at 1800 MDT
                                           |
K index... +23.5  LI... +0.2               | K index... +11.0  LI... +1.0
CAPE... +60.9  CIN... -4.9                 | CAPE... 0.0  CIN... -0.8
                                           |
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 -61.2 -78.2  210  49 25  -0.1  -0.0 | -61.5 -78.7  210  35 18   1.1   0.6
 45000 -59.4 -74.9  200  85 44   5.3   2.9 | -58.6 -73.5  200  76 39   4.7   2.6
 40000 -51.4 -60.5  190  96 49   4.7   2.6 | -51.6 -60.9  195  96 49   4.4   2.4
 38000 -48.6 -55.5  195  91 47   4.6   2.5 | -49.0 -56.2  195  94 48   4.3   2.3
 36000 -45.9 -50.6  195  87 45   4.6   2.5 | -46.4 -51.5  195  91 47   4.3   2.3
 34000 -42.3 -44.1  195  83 42   6.8   3.7 | -43.0 -45.4  195  87 45   7.0   3.8
 32000 -38.3 -36.9  200  78 40   6.8   3.7 | -38.8 -37.8  195  81 42   7.0   3.8
 30000 -33.0 -27.4  200  74 38   8.5   4.7 | -33.7 -28.7  200  77 40   8.0   4.4
 29000 -30.4 -22.7  200  72 37   8.5   4.7 | -31.3 -24.3  200  76 39   8.0   4.4
 28000 -27.9 -18.2  205  71 37   8.5   4.7 | -29.0 -20.2  205  75 39   7.9   4.4
 27000 -25.3 -13.5  200  68 35   8.6   4.7 | -26.4 -15.5  205  72 37   8.7   4.8
 26000 -22.7  -8.9  195  64 33   8.6   4.7 | -23.8 -10.8  200  69 36   8.8   4.8
 25000 -20.2  -4.4  190  60 31   8.5   4.7 | -21.2  -6.2  195  67 34   8.7   4.8
 24000 -17.9  -0.2  190  60 31   6.7   3.7 | -19.0  -2.2  190  65 33   5.4   3.0
 23000 -15.9   3.4  195  63 32   6.6   3.6 | -17.3   0.9  195  64 33   5.5   3.0
 22000 -13.9   7.0  195  66 34   6.6   3.6 | -15.6   3.9  200  64 33   5.5   3.0
 21000 -12.2  10.0  195  65 34   4.7   2.6 | -14.2   6.4  205  63 32   4.2   2.3
 20000 -10.8  12.6  200  61 31   4.6   2.5 | -12.9   8.8  210  59 30   4.2   2.3
 19500 -10.2  13.6  200  59 30   4.6   2.5 | -12.2  10.0  210  57 30   4.2   2.3
 19000  -9.5  14.9  200  57 29   4.6   2.5 | -11.6  11.1  210  56 29   4.1   2.2
 18500  -9.0  15.8  205  55 29   2.9   1.6 | -10.7  12.7  210  53 27   6.9   3.8
 18000  -8.5  16.7  205  55 28   3.1   1.7 |  -9.7  14.5  210  50 26   6.6   3.6
 17500  -8.1  17.4  205  53 28   3.7   2.0 |  -8.7  16.3  210  47 24   6.6   3.6
 17000  -7.5  18.5  205  49 25   4.1   2.2 |  -7.8  18.0  210  45 23   6.7   3.7
 16500  -7.0  19.4  205  45 23   4.6   2.5 |  -6.8  19.8  210  42 22   6.8   3.7
 16000  -6.0  21.2  205  40 21   8.5   4.6 |  -5.4  22.3  210  37 19   6.7   3.7
 15500  -4.3  24.3  205  34 17   8.6   4.7 |  -4.4  24.1  205  33 17   7.3   4.0
 15000  -3.1  26.4  205  32 16   9.1   5.0 |  -3.3  26.1  205  30 15   8.8   4.8
 14500  -1.8  28.8  205  30 15   9.2   5.0 |  -2.0  28.4  200  27 14   8.9   4.9
 14000  -0.5  31.1  200  28 14   8.8   4.8 |  -0.7  30.7  200  25 13   9.5   5.2
 13500   0.8  33.4  200  26 13   8.8   4.8 |   0.6  33.1  195  24 12   9.5   5.2
 13000   2.1  35.8  200  24 12   9.7   5.3 |   2.0  35.6  195  23 12   9.6   5.2
 12500   3.5  38.3  200  22 11   9.7   5.3 |   3.4  38.1  195  22 11   9.5   5.2
 12000   4.9  40.8  200  21 11   9.7   5.3 |   4.9  40.8  195  22 11   9.8   5.4
 11500   6.4  43.5  200  20 11   9.7   5.3 |   6.3  43.3  195  21 11   9.8   5.4
 11000   7.8  46.0  200  20 10   9.1   5.0 |   7.7  45.9  195  21 11   9.0   4.9
 10500   9.1  48.4  200  20 10   9.2   5.0 |   9.0  48.2  195  21 11   8.8   4.8
 10250   9.9  49.8  205  20 10  11.6   6.3 |   9.8  49.6  200  21 11  11.5   6.3
 10000  10.8  51.4  205  20 10  11.2   6.1 |  10.7  51.3  200  21 11  11.3   6.2
  9750  11.5  52.7  205  20 10   9.4   5.2 |  11.4  52.5  200  20 10   9.2   5.0
  9500  12.2  54.0  205  19 10   9.8   5.4 |  12.1  53.8  200  20 10   9.7   5.3
  9250  13.0  55.4  205  19 10   9.9   5.4 |  12.8  55.0  200  20 10   9.6   5.3
  9000  13.7  56.7  205  19 10   9.7   5.3 |  13.6  56.5  200  20 10   9.9   5.4
  8750  14.4  57.9  205  19 10   9.6   5.3 |  14.3  57.7  200  20 10  10.1   5.5
  8500  15.1  59.2  205  19 10   9.1   5.0 |  15.1  59.2  200  20 10   9.7   5.3
  8250  15.9  60.6  205  19 10  11.5   6.3 |  15.8  60.4  200  20 10  10.8   5.9
  8000  16.8  62.2  205  19 10  11.3   6.2 |  16.6  61.9  200  19 10  10.3   5.7
  7750  17.5  63.5  205  18  9   8.6   4.7 |  17.3  63.1  200  19 10   8.9   4.9
  7500  18.1  64.6  205  18  9   8.7   4.8 |  18.0  64.4  205  19 10   8.7   4.8
  7250  18.8  65.8  205  18  9   9.9   5.4 |  18.7  65.7  205  19 10  10.3   5.6
  7000  19.6  67.3  205  18  9  10.9   6.0 |  19.5  67.1  205  19 10  11.4   6.3
  6750  20.4  68.7  205  18  9   9.7   5.3 |  20.3  68.5  205  18  9   9.6   5.3
  6500  21.1  70.0  205  17  9   9.7   5.3 |  21.0  69.8  205  18  9   9.1   5.0
  6250  21.9  71.4  210  17  9  11.0   6.0 |  21.7  71.1  205  18  9   9.9   5.4
  6000  22.7  72.9  210  17  9  12.1   6.6 |  22.4  72.3  205  17  9  10.3   5.7
  5750  23.6  74.5  210  16  8  10.2   5.6 |  23.2  73.8  205  16  8   9.9   5.5
  5500  24.4  75.9  210  15  8  12.9   7.1 |  24.0  75.2  205  14  7  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.

CIN (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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