Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 040110
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1910 MDT Thursday, September 3, 2015

This forecast is for Friday, September 4, 2015:

If the trigger temperature of 79.5 F/26.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 774 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14173 ft MSL (8866 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9186 ft MSL (3879 ft AGL)
Thermal soaring outlook for Saturday 09/05..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 40576 ft MSL (35269 ft AGL)
Wave soaring outlook for Saturday 09/05........ Poor

Remarks...

Sunrise/Sunset.................... 06:30:05 / 19:27:43 MDT
Total possible sunshine........... 12 hr 57 min 38 sec (777 min 38 sec)
Altitude of sun at 12:58:26 MDT... 57.32 degrees

Upper air data from numerical model forecast valid on 09/04/2015 at 0600 MDT

Freezing level.................. 15654 ft MSL (10347 ft AGL)
Convective condensation level... 16420 ft MSL (11113 ft AGL)
Lifted condensation level....... 15535 ft MSL (10229 ft AGL)
Lifted index.................... -0.4
K index......................... +8.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.2 -81.8   240   39   20   0.7   0.4      M     M       M      M    M
 45000  -60.8 -77.4   245   46   24   4.2   2.3      M     M       M      M    M
 40000  -54.3 -65.7   245   62   32   6.7   3.7      M     M       M      M    M
 38000  -50.4 -58.7   235   57   30   6.5   3.6      M     M       M      M    M
 36000  -46.0 -50.8   225   55   28   6.2   3.4      M     M       M      M    M
 34000  -40.9 -41.6   225   54   28   8.7   4.8      M     M       M      M    M
 32000  -35.7 -32.3   235   53   27   8.6   4.7      M     M       M      M    M
 30000  -31.0 -23.8   240   46   24   7.5   4.1   44.9 112.8    11.7      M    M
 29000  -28.8 -19.8   240   42   21   7.5   4.1   44.0 111.3    11.2      M    M
 28000  -26.5 -15.7   245   38   19   7.7   4.2   43.3 110.0    10.8      M    M
 27000  -24.1 -11.4   240   34   18   8.2   4.5   42.6 108.7    10.3      M    M
 26000  -21.6  -6.9   235   31   16   8.2   4.5   42.0 107.6     9.9      M    M
 25000  -19.2  -2.6   225   29   15   8.5   4.7   41.5 106.7     9.6      M    M
 24000  -17.2   1.0   225   27   14   5.9   3.2   40.3 104.6     8.7      M    M
 23000  -15.4   4.3   225   25   13   5.9   3.2   38.9 102.0     7.7      M    M
 22000  -13.6   7.5   230   23   12   5.8   3.2   37.6  99.7     6.7      M    M
 21000  -11.6  11.1   235   20   11   7.1   3.9   36.5  97.7     5.8      M    M
 20000   -9.4  15.1   235   18    9   7.1   3.9   35.6  96.0     5.1      M    M
 19500   -8.3  17.1   235   17    9   7.1   3.9   35.1  95.2     4.8      M    M
 19000   -7.2  19.0   235   15    8   7.4   4.1   34.7  94.5     4.5      M    M
 18500   -5.5  22.1   235   15    8   7.6   4.2   34.1  93.5     4.0      M    M
 18000   -4.4  24.1   235   14    7   7.2   4.0   33.8  92.8     3.7      M    M
 17500   -3.4  25.9   235   14    7   6.9   3.8   33.3  91.9     3.3      M    M
 17000   -2.4  27.7   230   13    7   6.9   3.8   32.8  91.0     2.8      M    M
 16500   -1.4  29.5   230   13    7   6.3   3.4   32.3  90.1     2.3      M    M
 16000   -0.5  31.1   230   12    6   6.4   3.5   31.7  89.0     1.8      M    M
 15500    0.4  32.7   230   11    6   6.4   3.5   31.1  88.0     1.3      M    M
 15000    1.4  34.5   230   10    5   6.5   3.6   30.6  87.0     0.7      M    M
 14500    2.3  36.1   230    8    4   6.9   3.8   30.0  86.1     0.2      M    M
 14000    3.4  38.1   235    7    4   7.4   4.1   29.6  85.4    -0.2    751  3.8
 13500    4.5  40.1   245    6    3   7.5   4.1   29.3  84.7    -0.5    703  3.6
 13000    5.6  42.1   260    5    3   7.6   4.2   28.9  84.0    -0.9    656  3.3
 12500    6.7  44.1   275    5    3   7.7   4.2   28.6  83.4    -1.3    608  3.1
 12000    7.9  46.2   295    5    3   8.6   4.7   28.3  83.0    -1.6    558  2.8
 11500    9.1  48.4   310    6    3   8.5   4.7   28.1  82.6    -1.9    507  2.6
 11000   10.3  50.5   315    8    4   8.7   4.7   27.9  82.3    -2.1    455  2.3
 10500   11.6  52.9   315    9    5   5.5   3.0   27.8  82.1    -2.3    402  2.0
 10250   11.8  53.2   320   10    5   5.4   3.0   27.3  81.2    -2.8    386  2.0
 10000   12.5  54.5   315   11    6  10.6   5.8   27.3  81.1    -2.9    360  1.8
  9750   13.2  55.8   315   12    6  10.1   5.5   27.3  81.1    -2.9    330  1.7
  9500   13.9  57.0   310   13    7  10.5   5.8   27.3  81.2    -2.9    301  1.5
  9250   14.6  58.3   310   14    7   7.8   4.3   27.3  81.2    -2.9    273  1.4
  9000   15.1  59.2   310   15    8   7.1   3.9   27.1  80.8    -3.2    252  1.3
  8750   15.7  60.3   305   16    8   8.9   4.9   27.0  80.6    -3.4    227  1.2
  8500   16.2  61.2   305   17    9   8.3   4.6   26.9  80.4    -3.5    203  1.0
  8250   16.8  62.2   300   17    9   7.3   4.0   26.8  80.2    -3.7    179  0.9
  8000   17.2  63.0   300   17    9   6.2   3.4   26.5  79.7    -4.0    158  0.8
  7750   17.7  63.9   300   16    8   6.2   3.4   26.2  79.2    -4.3    137  0.7
  7500   18.1  64.6   300   15    8   5.2   2.9   26.0  78.7    -4.6    117  0.6
  7250   18.4  65.1   295   14    7   3.5   1.9   25.5  78.0    -5.1    101  0.5
  7000   18.6  65.5   295   12    6   2.5   1.4   25.0  77.0    -5.6     86  0.4
  6750   18.8  65.8   290   10    5   2.6   1.4   24.5  76.0    -6.1     73  0.4
  6500   19.0  66.2   285    8    4  -1.9  -1.0   23.8  74.9    -6.8     62  0.3
  6250   18.6  65.5   270    7    4  -6.2  -3.4   22.7  72.8    -7.9     67  0.3
  6000   18.1  64.6   255    6    3  -4.4  -2.4   21.5  70.8    -9.1     72  0.4
  5750   17.8  64.0   235    7    4  -6.0  -3.3   20.5  68.8   -10.2     75  0.4
  5500   16.9  62.4   225    8    4 -18.0  -9.9   18.9  66.1   -11.8     95  0.5

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

           09/04/2015 at 0900 MDT          |       09/04/2015 at 1200 MDT
                                           |
K index... +4.1  LI... -1.4                | K index... +17.1  LI... -1.0
CAPE... +20.0  CIN... -206.6               | CAPE... +48.4  CIN... -62.3
                                           |
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  240  39 20  -0.0  -0.0 | -63.7 -82.7  240  39 20  -0.3  -0.1
 45000 -61.5 -78.7  235  51 26   4.9   2.7 | -61.9 -79.4  240  58 30   5.4   3.0
 40000 -53.6 -64.5  245  61 31   6.3   3.5 | -53.2 -63.8  245  67 35   6.7   3.7
 38000 -49.8 -57.6  245  57 29   6.4   3.5 | -49.1 -56.4  240  64 33   6.8   3.7
 36000 -46.0 -50.8  240  53 27   6.3   3.5 | -45.1 -49.2  235  61 31   6.7   3.7
 34000 -41.4 -42.5  235  47 24   7.9   4.3 | -40.5 -40.9  235  55 28   7.8   4.3
 32000 -36.7 -34.1  230  42 21   8.0   4.4 | -35.8 -32.4  230  48 25   7.8   4.3
 30000 -31.4 -24.5  225  37 19   9.1   5.0 | -30.5 -22.9  225  41 21   8.1   4.4
 29000 -28.7 -19.7  220  35 18   9.1   5.0 | -28.1 -18.6  220  39 20   8.1   4.4
 28000 -25.4 -13.7  220  33 17   7.1   3.9 | -25.7 -14.3  215  36 19   7.3   4.0
 27000 -23.6 -10.5  220  30 16   6.1   3.3 | -23.7 -10.7  215  32 17   6.8   3.7
 26000 -21.8  -7.2  220  28 15   6.1   3.3 | -21.7  -7.1  215  28 14   6.8   3.8
 25000 -20.1  -4.2  220  26 13   6.0   3.3 | -19.7  -3.5  215  24 12   6.9   3.8
 24000 -18.1  -0.6  215  25 13   6.8   3.8 | -17.6   0.3  215  22 11   7.1   3.9
 23000 -16.1   3.0  210  25 13   6.9   3.8 | -15.5   4.1  210  20 10   7.1   3.9
 22000 -14.1   6.6  205  24 12   6.8   3.7 | -13.4   7.9  210  18  9   7.1   3.9
 21000 -12.6   9.3  205  23 12   4.6   2.5 | -11.6  11.1  205  17  9   5.7   3.1
 20000 -11.2  11.8  210  21 11   4.6   2.5 |  -9.9  14.2  200  16  8   5.7   3.1
 19500 -10.5  13.1  210  21 11   4.3   2.3 |  -9.0  15.8  200  16  8   5.6   3.1
 19000  -9.6  14.7  210  20 10   9.8   5.4 |  -8.0  17.6  195  15  8   8.0   4.4
 18500  -7.9  17.8  210  20 10  10.9   6.0 |  -6.7  19.9  195  15  8   8.5   4.7
 18000  -6.2  20.8  215  19 10  11.1   6.1 |  -5.5  22.1  200  15  8   8.3   4.5
 17500  -4.5  23.9  215  19 10  11.3   6.2 |  -4.5  23.9  200  15  8   6.1   3.4
 17000  -2.8  27.0  220  18  9  11.4   6.3 |  -3.6  25.5  205  15  8   6.3   3.4
 16500  -1.3  29.7  220  18  9   8.3   4.6 |  -2.6  27.3  210  15  8   7.5   4.1
 16000  -0.1  31.8  220  17  9   7.7   4.2 |  -1.5  29.3  210  16  8   7.7   4.2
 15500   1.1  34.0  220  17  9   7.3   4.0 |   0.1  32.2  210  16  8   7.6   4.2
 15000   2.6  36.7  220  15  8   6.6   3.6 |   1.3  34.3  205  16  8   7.6   4.2
 14500   3.6  38.5  215  14  7   6.1   3.4 |   2.4  36.3  205  15  8   7.5   4.1
 14000   4.4  39.9  215  12  6   5.9   3.3 |   3.5  38.3  200  14  7   7.4   4.1
 13500   5.2  41.4  210  11  5   6.1   3.4 |   4.6  40.3  195  14  7   7.3   4.0
 13000   6.2  43.2  205   9  5   6.6   3.6 |   5.7  42.3  185  13  7   7.0   3.9
 12500   7.1  44.8  200   7  4   6.8   3.7 |   6.7  44.1  180  12  6   7.2   4.0
 12000   8.1  46.6  195   5  3   7.7   4.2 |   7.8  46.0  170  12  6   8.2   4.5
 11500   9.2  48.6  180   3  2   7.7   4.2 |   9.0  48.2  160  11  6   8.2   4.5
 11000  10.3  50.5  160   2  1   7.9   4.3 |  10.2  50.4  155  10  5   8.0   4.4
 10500  11.4  52.5  065   1  0   4.7   2.6 |  11.4  52.5  150  10  5   5.2   2.8
 10250  11.7  53.1  045   1  1   6.1   3.3 |  11.6  52.9  145  10  5   6.2   3.4
 10000  12.4  54.3  010   2  1  11.5   6.3 |  12.3  54.1  145   9  5  10.8   5.9
  9750  13.2  55.8  355   3  2  10.2   5.6 |  13.1  55.6  140   8  4   9.7   5.3
  9500  13.9  57.0  350   4  2  10.0   5.5 |  13.8  56.8  140   7  4   9.6   5.3
  9250  14.6  58.3  340   6  3   7.6   4.2 |  14.5  58.1  135   6  3   8.3   4.5
  9000  15.2  59.4  335   7  4   8.7   4.7 |  15.1  59.2  130   5  3   8.5   4.7
  8750  15.9  60.6  330   8  4  10.7   5.9 |  15.7  60.3  130   4  2   9.1   5.0
  8500  16.6  61.9  325  10  5   9.6   5.3 |  16.4  61.5  135   3  2   9.1   5.0
  8250  17.2  63.0  320  11  6   8.3   4.5 |  17.0  62.6  145   3  1  10.1   5.5
  8000  17.7  63.9  315  12  6   7.1   3.9 |  17.7  63.9  160   2  1   9.7   5.3
  7750  18.1  64.6  310  12  6   6.8   3.7 |  18.3  64.9  170   3  1   8.6   4.7
  7500  18.6  65.5  305  12  6   6.1   3.3 |  18.9  66.0  180   3  2   9.5   5.2
  7250  19.0  66.2  300  11  5   5.2   2.8 |  19.6  67.3  180   3  2  10.6   5.8
  7000  19.3  66.7  295   9  5   4.8   2.6 |  20.4  68.7  180   3  2  10.4   5.7
  6750  19.6  67.3  290   8  4   4.2   2.3 |  21.1  70.0  180   3  2   9.8   5.4
  6500  19.8  67.6  280   7  3   1.2   0.6 |  21.9  71.4  185   3  2  10.3   5.7
  6250  19.8  67.6  265   6  3  -0.8  -0.4 |  22.7  72.9  185   3  2  11.4   6.3
  6000  19.7  67.5  250   5  3  -0.6  -0.3 |  23.5  74.3  185   3  2  10.1   5.5
  5750  19.6  67.3  230   5  3  -0.8  -0.4 |  24.3  75.7  185   3  2  12.4   6.8
  5500  19.6  67.3  220   5  3   2.3   1.3 |  25.5  77.9  185   3  2  22.4  12.3

           09/04/2015 at 1500 MDT          |       09/04/2015 at 1800 MDT
                                           |
K index... +28.5  LI... -0.6               | K index... +31.5  LI... -1.3
CAPE... +4.6  CIN... -11.6                 | CAPE... +86.0  CIN... -36.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.2 -83.6  240  42 22   0.3   0.2 | -63.9 -83.0  235  43 22   0.3   0.2
 45000 -61.4 -78.5  245  65 34   5.5   3.0 | -61.2 -78.2  245  65 34   5.1   2.8
 40000 -52.9 -63.2  245  82 42   6.6   3.6 | -53.2 -63.8  245  82 42   6.7   3.7
 38000 -49.0 -56.2  240  75 39   6.6   3.6 | -49.2 -56.6  245  69 35   6.8   3.7
 36000 -45.0 -49.0  240  68 35   6.5   3.6 | -45.1 -49.2  240  55 28   6.6   3.6
 34000 -40.2 -40.4  240  63 32   8.3   4.5 | -39.8 -39.6  240  45 23   9.2   5.0
 32000 -35.3 -31.5  240  58 30   8.3   4.6 | -34.3 -29.7  240  35 18   9.0   4.9
 30000 -29.9 -21.8  235  47 24   8.0   4.4 | -28.8 -19.8  230  32 17   8.1   4.4
 29000 -27.5 -17.5  235  42 21   8.0   4.4 | -26.4 -15.5  230  33 17   8.1   4.4
 28000 -25.1 -13.2  230  36 19   7.7   4.2 | -24.0 -11.2  225  33 17   7.7   4.2
 27000 -22.9  -9.2  225  34 17   7.6   4.2 | -21.8  -7.2  225  31 16   7.5   4.1
 26000 -20.7  -5.3  220  31 16   7.7   4.2 | -19.6  -3.3  220  29 15   7.5   4.1
 25000 -18.4  -1.1  220  29 15   7.8   4.3 | -17.4   0.7  215  28 14   7.6   4.2
 24000 -16.5   2.3  215  27 14   6.2   3.4 | -15.5   4.1  210  26 13   6.2   3.4
 23000 -14.7   5.5  215  24 12   6.2   3.4 | -13.7   7.3  205  24 12   6.2   3.4
 22000 -12.9   8.8  210  22 11   6.2   3.4 | -11.9  10.6  200  22 11   6.2   3.4
 21000 -11.1  12.0  205  20 10   6.3   3.5 | -10.1  13.8  195  21 11   6.0   3.3
 20000  -9.2  15.4  195  18  9   6.4   3.5 |  -8.4  16.9  190  20 10   6.1   3.3
 19500  -8.3  17.1  190  18  9   6.4   3.5 |  -7.5  18.5  185  20 10   6.1   3.3
 19000  -7.4  18.7  190  17  9   5.7   3.1 |  -6.7  19.9  185  20 10   6.0   3.3
 18500  -6.6  20.1  185  16  8   5.5   3.0 |  -5.8  21.6  180  21 11   6.0   3.3
 18000  -5.8  21.6  185  15  8   5.5   3.0 |  -4.9  23.2  180  21 11   6.0   3.3
 17500  -4.9  23.2  180  14  7   6.4   3.5 |  -4.1  24.6  180  22 11   5.7   3.1
 17000  -4.0  24.8  180  14  7   6.3   3.5 |  -3.3  26.1  180  22 11   5.8   3.2
 16500  -3.1  26.4  180  14  7   6.3   3.5 |  -2.5  27.5  180  22 11   5.7   3.1
 16000  -1.7  28.9  175  13  7   6.2   3.4 |  -1.3  29.7  180  21 11   5.7   3.1
 15500  -0.7  30.7  175  13  7   7.3   4.0 |  -0.4  31.3  180  21 11   6.2   3.4
 15000   0.3  32.5  170  13  6   7.4   4.0 |   0.5  32.9  180  21 11   6.4   3.5
 14500   1.4  34.5  165  13  6   7.7   4.2 |   1.4  34.5  180  20 10   6.6   3.6
 14000   2.6  36.7  160  12  6   8.0   4.4 |   2.4  36.3  180  19 10   6.9   3.8
 13500   3.7  38.7  150  13  6   8.5   4.7 |   3.3  37.9  180  18  9   6.8   3.7
 13000   5.1  41.2  150  13  6   9.5   5.2 |   4.3  39.7  180  17  9   6.6   3.6
 12500   6.5  43.7  145  13  6   9.5   5.2 |   5.2  41.4  175  16  8   6.7   3.7
 12000   7.9  46.2  145  12  6   9.7   5.3 |   6.3  43.3  175  15  8   8.0   4.4
 11500   9.3  48.7  145  12  6   9.6   5.3 |   7.5  45.5  175  14  7   7.9   4.3
 11000  10.7  51.3  145  12  6   8.4   4.6 |   8.6  47.5  175  12  6   7.2   4.0
 10500  11.9  53.4  145  12  6  12.3   6.8 |   9.7  49.5  175  10  5   4.9   2.7
 10250  13.0  55.4  145  12  6  13.3   7.3 |  10.0  50.0  175  10  5   5.8   3.2
 10000  13.7  56.7  145  12  6   8.8   4.8 |  10.6  51.1  175   9  5   9.7   5.3
  9750  14.5  58.1  145  11  6  10.1   5.5 |  11.3  52.3  180   8  4   8.7   4.8
  9500  15.2  59.4  145  11  6   9.5   5.2 |  11.9  53.4  180   7  4   8.8   4.8
  9250  15.9  60.6  145  11  6   9.0   4.9 |  12.5  54.5  180   6  3   7.7   4.2
  9000  16.6  61.9  145  11  6   9.8   5.4 |  13.1  55.6  185   5  3   8.5   4.7
  8750  17.3  63.1  145  11  6  10.5   5.8 |  13.8  56.8  190   4  2   9.7   5.3
  8500  18.1  64.6  145  11  6  10.3   5.6 |  14.5  58.1  195   4  2   9.4   5.2
  8250  18.9  66.0  145  11  6  10.2   5.6 |  15.2  59.4  205   3  2   9.5   5.2
  8000  19.6  67.3  145  11  5   9.9   5.4 |  16.0  60.8  215   3  1   9.8   5.4
  7750  20.4  68.7  145  10  5   9.4   5.2 |  16.7  62.1  225   2  1  10.0   5.5
  7500  21.1  70.0  145  10  5   9.9   5.5 |  17.4  63.3  235   2  1  10.0   5.5
  7250  21.8  71.2  145  10  5  10.8   5.9 |  18.2  64.8  245   2  1  10.1   5.5
  7000  22.7  72.9  145  10  5  10.7   5.9 |  18.9  66.0  255   2  1  10.0   5.5
  6750  23.4  74.1  145  10  5   9.6   5.3 |  19.7  67.5  265   2  1   9.6   5.3
  6500  24.1  75.4  145  10  5  10.0   5.5 |  20.4  68.7  275   2  1  10.0   5.5
  6250  24.9  76.8  145   9  5  11.1   6.1 |  21.2  70.2  285   2  1  10.7   5.9
  6000  25.7  78.3  145   9  5  10.2   5.6 |  22.0  71.6  290   2  1  10.2   5.6
  5750  26.5  79.7  145   9  4  11.9   6.5 |  22.7  72.9  300   3  1  10.3   5.7
  5500  27.7  81.9  140   8  4  20.7  11.4 |  23.5  74.3  295   3  1  12.3   6.8
________________________________________________________________________________

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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