Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210010
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1810 MDT Saturday, September 20, 2014

This forecast is for Sunday, September 21, 2014:

If the trigger temperature of 69.0 F/20.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 200 ft/min (1.0 m/s)
   Maximum height of thermals.................. 10715 ft MSL (5428 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1130 MDT
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................. 7311 ft MSL (2024 ft AGL)
Thermal soaring outlook for Monday 09/22....... Poor

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 PVA
Potential height of wave....................... 14635 ft MSL (9348 ft AGL)
Wave soaring outlook for Monday 09/22.......... Poor

Remarks...

Sunrise/Sunset.................... 06:46:10 / 18:59:42 MDT
Total possible sunshine........... 12 hr 13 min 32 sec (733 min 32 sec)
Altitude of sun at 12:52:26 MDT... 50.75 degrees

Upper air data from numerical model forecast valid on 09/21/2014 at 0600 MDT

Freezing level.................. 15132 ft MSL (9845 ft AGL)
Convective condensation level... 11747 ft MSL (6460 ft AGL)
Lifted condensation level....... 11147 ft MSL (5859 ft AGL)
Lifted index.................... +1.0
K index......................... +27.7

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  -67.3 -89.1   290   43   22   2.8   1.6      M     M       M      M    M
 45000  -61.0 -77.8   280   63   33   6.6   3.6      M     M       M      M    M
 40000  -51.2 -60.2   280   70   36   6.1   3.3      M     M       M      M    M
 38000  -47.6 -53.7   280   61   32   6.1   3.3      M     M       M      M    M
 36000  -43.9 -47.0   280   53   27   6.0   3.3      M     M       M      M    M
 34000  -40.0 -40.0   280   45   23   6.7   3.7      M     M       M      M    M
 32000  -35.9 -32.6   275   37   19   6.5   3.6      M     M       M      M    M
 30000  -30.8 -23.4   275   34   18   8.0   4.4   45.3 113.6    17.5      M    M
 29000  -28.4 -19.1   275   34   17   8.0   4.4   44.7 112.4    17.2      M    M
 28000  -26.0 -14.8   275   33   17   7.3   4.0   44.0 111.3    16.9      M    M
 27000  -23.9 -11.0   275   30   15   7.3   4.0   43.0 109.4    16.3      M    M
 26000  -21.7  -7.1   275   27   14   7.3   4.0   42.1 107.7    15.7      M    M
 25000  -19.5  -3.1   270   24   12   7.1   3.9   41.3 106.3    15.2      M    M
 24000  -17.5   0.5   275   20   10   6.8   3.7   40.1 104.1    14.5      M    M
 23000  -15.4   4.3   280   16    8   6.8   3.7   39.0 102.2    13.8      M    M
 22000  -13.3   8.1   290   12    6   6.7   3.7   38.1 100.5    13.2      M    M
 21000  -11.4  11.5   295   11    6   6.6   3.6   36.9  98.3    12.3      M    M
 20000   -9.4  15.1   295   10    5   6.6   3.6   35.8  96.4    11.4      M    M
 19500   -8.4  16.9   295    9    5   6.6   3.6   35.3  95.5    11.1      M    M
 19000   -7.4  18.7   300    9    5   7.5   4.1   34.8  94.6    10.7      M    M
 18500   -6.4  20.5   300   10    5   7.6   4.2   34.4  93.9    10.3      M    M
 18000   -5.3  22.5   300   10    5   7.2   4.0   34.1  93.3    10.0      M    M
 17500   -4.4  24.1   300   11    5   7.0   3.8   33.5  92.4     9.5      M    M
 17000   -3.5  25.7   295   11    6   7.1   3.9   33.1  91.5     9.0      M    M
 16500   -2.5  27.5   290   12    6   6.7   3.7   32.6  90.6     8.5      M    M
 16000   -1.6  29.1   280   12    6   6.9   3.8   32.1  89.7     8.0      M    M
 15500   -0.7  30.7   270   12    6   5.4   3.0   31.5  88.7     7.5      M    M
 15000    0.4  32.7   255   14    7   5.2   2.9   30.3  86.6     6.4      M    M
 14500    1.0  33.8   245   14    7   3.6   2.0   29.5  85.0     5.6      M    M
 14000    1.5  34.7   235   14    7   3.7   2.0   28.5  83.2     4.7      M    M
 13500    2.0  35.6   230   14    7   4.3   2.3   27.5  81.5     3.8      M    M
 13000    2.6  36.7   225   13    7   4.3   2.4   26.6  79.9     3.0      M    M
 12500    3.3  37.9   225   12    6   5.9   3.2   25.8  78.5     2.2      M    M
 12000    4.2  39.6   225   10    5   6.5   3.6   25.3  77.5     1.6      M    M
 11500    5.1  41.2   225    9    5   5.7   3.1   24.8  76.6     1.0      M    M
 11000    5.8  42.4   220    9    4   5.3   2.9   24.1  75.3     0.3      M    M
 10500    6.5  43.7   210    9    4   3.9   2.1   23.3  74.0    -0.4    381  1.9
 10250    6.8  44.2   210    9    5   4.3   2.3   22.8  73.1    -0.9    366  1.9
 10000    7.2  45.0   200    9    5   7.1   3.9   22.5  72.6    -1.2    345  1.8
  9750    7.8  46.0   195   10    5   7.7   4.2   22.4  72.3    -1.3    320  1.6
  9500    8.4  47.1   190   11    5   7.3   4.0   22.2  71.9    -1.5    296  1.5
  9250    8.9  48.0   185   11    6   6.7   3.7   22.0  71.6    -1.7    273  1.4
  9000    9.4  48.9   180   11    6   8.3   4.5   21.8  71.2    -1.9    249  1.3
  8750   10.1  50.2   180   12    6   8.8   4.9   21.7  71.1    -1.9    221  1.1
  8500   10.7  51.3   175   13    6   7.2   3.9   21.6  70.8    -2.0    196  1.0
  8250   11.2  52.2   170   13    7   6.4   3.5   21.3  70.4    -2.2    173  0.9
  8000   11.8  53.2   165   13    7   8.5   4.7   21.1  70.0    -2.5    150  0.8
  7750   12.4  54.3   165   14    7   8.2   4.5   21.1  70.0    -2.5    122  0.6
  7500   12.9  55.2   160   14    7   5.6   3.1   20.8  69.5    -2.8    100  0.5
  7250   13.3  55.9   150   14    7   6.3   3.5   20.5  69.0    -3.1     80  0.4
  7000   13.8  56.8   145   14    7   5.1   2.8   20.3  68.5    -3.4     59  0.3
  6750   14.1  57.4   140   14    7   4.2   2.3   19.9  67.7    -3.8     42  0.2
  6500   14.4  57.9   135   12    6   4.5   2.5   19.4  67.0    -4.2     25  0.1
  6250   14.7  58.5   125   11    6   4.4   2.4   19.1  66.3    -4.6      9  0.0
  6000   15.0  59.0   115   10    5   4.7   2.6   18.7  65.6    -5.1      M    M
  5750   15.3  59.5   105    8    4   5.9   3.2   18.3  65.0    -5.5      M    M
  5500   15.7  60.3   085    6    3   6.8   3.7   18.1  64.6    -5.8      M    M

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

           09/21/2014 at 0900 MDT          |       09/21/2014 at 1200 MDT
                                           |
K index... +28.9  LI... -0.6               | K index... +29.4  LI... -0.2
CAPE... +46.5  CIN... -6.1                 | CAPE... +0.2  CIN... -5.1
                                           |
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 -66.9 -88.4  290  41 21   2.2   1.2 | -66.5 -87.7  285  38 20   2.0   1.1
 45000 -61.4 -78.5  285  61 31   6.4   3.5 | -61.3 -78.3  280  58 30   6.2   3.4
 40000 -51.9 -61.4  280  67 34   5.9   3.2 | -52.1 -61.8  280  67 34   5.8   3.2
 38000 -48.3 -54.9  285  57 29   5.9   3.2 | -48.6 -55.5  275  55 28   5.8   3.2
 36000 -44.8 -48.6  285  46 24   5.7   3.2 | -45.1 -49.2  275  43 22   5.5   3.0
 34000 -40.3 -40.5  285  45 23   7.7   4.2 | -40.6 -41.1  265  39 20   7.9   4.4
 32000 -35.6 -32.1  280  44 23   7.6   4.2 | -35.8 -32.4  260  36 19   7.8   4.3
 30000 -30.4 -22.7  285  35 18   7.8   4.3 | -30.7 -23.3  275  28 14   7.5   4.1
 29000 -28.1 -18.6  285  31 16   7.8   4.3 | -28.5 -19.3  290  25 13   7.5   4.1
 28000 -25.8 -14.4  290  26 14   7.4   4.1 | -26.2 -15.2  300  24 12   7.7   4.2
 27000 -23.6 -10.5  290  24 12   7.4   4.1 | -23.9 -11.0  295  22 11   7.7   4.2
 26000 -21.4  -6.5  290  22 11   7.5   4.1 | -21.6  -6.9  290  20 10   7.7   4.2
 25000 -19.2  -2.6  285  20 10   7.1   3.9 | -19.3  -2.7  285  18  9   7.3   4.0
 24000 -17.2   1.0  290  17  9   6.3   3.5 | -17.3   0.9  285  14  7   6.4   3.5
 23000 -15.3   4.5  295  15  8   6.4   3.5 | -15.4   4.3  290  10  5   6.4   3.5
 22000 -13.3   8.1  305  12  6   6.3   3.5 | -13.4   7.9  290   6  3   6.3   3.4
 21000 -11.5  11.3  305  11  6   6.3   3.4 | -11.6  11.1  295   5  2   6.1   3.3
 20000  -9.6  14.7  305  10  5   6.3   3.4 |  -9.8  14.4  295   3  2   6.1   3.3
 19500  -8.7  16.3  305   9  5   6.3   3.5 |  -8.9  16.0  295   2  1   6.0   3.3
 19000  -7.8  18.0  305   8  4   6.0   3.3 |  -8.0  17.6  300   2  1   6.6   3.6
 18500  -7.0  19.4  310   9  4   6.2   3.4 |  -7.1  19.2  310   2  1   6.6   3.6
 18000  -6.1  21.0  310   9  4   6.8   3.7 |  -6.2  20.8  315   1  1   6.9   3.8
 17500  -5.2  22.6  310   9  4   7.2   4.0 |  -5.2  22.6  315   2  1   7.0   3.9
 17000  -4.2  24.4  310   8  4   7.4   4.1 |  -4.3  24.3  315   2  1   7.2   3.9
 16500  -3.2  26.2  305   8  4   6.7   3.7 |  -3.3  26.1  300   2  1   6.5   3.6
 16000  -2.3  27.9  295   8  4   6.8   3.7 |  -2.4  27.7  285   3  2   6.7   3.7
 15500  -1.4  29.5  285   8  4   6.8   3.7 |  -1.1  30.0  265   5  2   6.5   3.6
 15000   0.0  32.0  265  10  5   7.0   3.8 |  -0.2  31.6  260   6  3   6.7   3.7
 14500   0.9  33.6  255  11  6   4.8   2.6 |   0.6  33.1  255   8  4   5.3   2.9
 14000   1.6  34.9  245  12  6   5.1   2.8 |   1.4  34.5  250  10  5   5.4   2.9
 13500   2.2  36.0  235  13  7   3.4   1.8 |   2.3  36.1  245  12  6   6.7   3.7
 13000   2.6  36.7  225  13  7   3.0   1.7 |   3.3  37.9  240  13  7   6.8   3.7
 12500   3.1  37.6  215  13  7   5.6   3.1 |   4.3  39.7  235  14  7   6.5   3.5
 12000   4.1  39.4  215  12  6   6.7   3.7 |   5.2  41.4  230  15  8   6.3   3.5
 11500   5.0  41.0  220  10  5   6.4   3.5 |   6.1  43.0  225  15  8   6.3   3.4
 11000   5.9  42.6  215  11  6   6.3   3.4 |   7.0  44.6  225  15  8   6.3   3.4
 10500   6.7  44.1  215  12  6   3.5   1.9 |   7.8  46.0  225  14  7   4.1   2.2
 10250   6.8  44.2  210  13  7   2.1   1.2 |   8.0  46.4  220  14  7   3.1   1.7
 10000   7.1  44.8  210  13  7   3.6   2.0 |   8.2  46.8  220  14  7   4.4   2.4
  9750   7.4  45.3  205  15  8   4.1   2.3 |   8.5  47.3  215  15  7   4.3   2.4
  9500   7.7  45.9  200  15  8   4.9   2.7 |   8.8  47.8  210  15  8   3.1   1.7
  9250   8.1  46.6  195  16  8   5.0   2.8 |   9.0  48.2  205  15  8   2.6   1.4
  9000   8.5  47.3  195  16  8   6.2   3.4 |   9.2  48.6  200  15  8   2.8   1.6
  8750   9.0  48.2  190  17  9   6.9   3.8 |   9.4  48.9  195  14  7   3.7   2.0
  8500   9.5  49.1  185  17  9   5.4   3.0 |   9.7  49.5  190  12  6   4.9   2.7
  8250   9.9  49.8  185  16  8   5.2   2.8 |  10.1  50.2  180  11  6   4.7   2.6
  8000  10.3  50.5  185  16  8   5.3   2.9 |  10.5  50.9  175   9  5   6.2   3.4
  7750  10.7  51.3  185  16  8   4.7   2.6 |  11.1  52.0  170   8  4   9.4   5.2
  7500  11.0  51.8  180  14  7   4.2   2.3 |  11.8  53.2  165   7  4  10.0   5.5
  7250  11.3  52.3  175  13  7   4.5   2.5 |  12.6  54.7  165   7  3  10.3   5.6
  7000  11.6  52.9  170  12  6   3.7   2.0 |  13.3  55.9  160   6  3   8.5   4.7
  6750  11.9  53.4  160  10  5   4.7   2.6 |  13.9  57.0  155   6  3   9.2   5.0
  6500  12.3  54.1  155   8  4   6.3   3.5 |  14.7  58.5  155   5  3  11.5   6.3
  6250  12.8  55.0  140   7  3   5.4   3.0 |  15.5  59.9  155   5  3  11.0   6.0
  6000  13.2  55.8  120   5  3   7.7   4.2 |  16.4  61.5  155   5  2  10.7   5.9
  5750  13.9  57.0  115   5  2  11.5   6.3 |  17.2  63.0  150   4  2  15.4   8.4
  5500  14.8  58.6  105   4  2  11.2   6.1 |  18.7  65.7  150   4  2  24.3  13.3

           09/21/2014 at 1500 MDT          |       09/21/2014 at 1800 MDT
                                           |
K index... +28.5  LI... -1.6               | K index... +26.4  LI... -1.5
CAPE... +139.7  CIN... -12.8               | CAPE... +212.1  CIN... -24.5
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.6 -87.9  285  37 19   3.0   1.6 | -66.5 -87.7  290  35 18   3.3   1.8
 45000 -60.6 -77.1  280  54 28   5.6   3.1 | -60.3 -76.5  285  50 26   5.4   3.0
 40000 -52.2 -62.0  275  68 35   5.2   2.9 | -52.1 -61.8  280  68 35   5.5   3.0
 38000 -49.1 -56.4  270  52 27   5.2   2.9 | -48.8 -55.8  280  53 27   5.5   3.0
 36000 -46.0 -50.8  265  37 19   4.7   2.6 | -45.5 -49.9  285  39 20   5.2   2.9
 34000 -40.7 -41.3  255  30 15   9.4   5.2 | -40.6 -41.1  285  33 17   8.6   4.7
 32000 -34.3 -29.7  250  24 12  10.0   5.5 | -34.8 -30.6  275  29 15   9.2   5.1
 30000 -29.5 -21.1  250  21 11   7.9   4.3 | -29.8 -21.6  270  27 14   8.4   4.6
 29000 -27.2 -17.0  250  19 10   8.0   4.4 | -27.3 -17.1  265  26 13   8.4   4.6
 28000 -24.9 -12.8  250  17  9   6.8   3.7 | -24.9 -12.8  260  25 13   7.2   4.0
 27000 -22.9  -9.2  250  15  8   6.7   3.7 | -22.8  -9.0  255  24 12   7.1   3.9
 26000 -20.9  -5.6  255  13  7   6.7   3.7 | -20.7  -5.3  255  23 12   7.1   3.9
 25000 -18.9  -2.0  260  11  6   6.3   3.5 | -18.6  -1.5  245  22 11   7.1   3.9
 24000 -17.4   0.7  245   9  4   5.0   2.8 | -16.6   2.1  240  20 10   6.7   3.7
 23000 -15.9   3.4  225   7  4   5.1   2.8 | -14.6   5.7  235  19 10   6.8   3.7
 22000 -14.4   6.1  195   7  3   5.8   3.2 | -12.7   9.1  230  17  9   6.5   3.6
 21000 -12.3   9.9  190   7  3   7.1   3.9 | -11.0  12.2  220  15  8   5.7   3.2
 20000 -10.2  13.6  185   7  3   7.1   3.9 |  -9.3  15.3  210  13  7   5.8   3.2
 19500  -9.1  15.6  185   7  3   7.1   3.9 |  -8.5  16.7  205  12  6   5.8   3.2
 19000  -8.1  17.4  180   6  3   7.2   4.0 |  -7.6  18.3  200  12  6   5.6   3.1
 18500  -7.0  19.4  175   5  3   7.2   4.0 |  -6.8  19.8  195  11  6   5.6   3.1
 18000  -5.9  21.4  170   4  2   7.1   3.9 |  -6.0  21.2  185  11  6   5.5   3.0
 17500  -4.9  23.2  160   4  2   7.0   3.8 |  -5.2  22.6  185  10  5   5.2   2.9
 17000  -4.0  24.8  150   3  1   7.1   3.9 |  -4.5  23.9  180   9  5   5.4   2.9
 16500  -3.1  26.4  150   2  1   5.7   3.1 |  -3.8  25.2  180   8  4   4.2   2.3
 16000  -2.3  27.9  165   2  1   6.0   3.3 |  -3.2  26.2  175   8  4   4.2   2.3
 15500  -1.1  30.0  215   2  1   5.7   3.1 |  -2.2  28.0  170   8  4   5.3   2.9
 15000  -0.3  31.5  230   4  2   5.8   3.2 |  -1.4  29.5  175   8  4   5.2   2.8
 14500   0.5  32.9  235   5  3   5.2   2.8 |  -0.7  30.7  180   7  4   5.8   3.2
 14000   1.3  34.3  240   7  3   5.1   2.8 |   0.2  32.4  185   7  4   5.8   3.2
 13500   2.1  35.8  240   8  4   6.7   3.7 |   1.0  33.8  190   8  4   6.5   3.5
 13000   3.2  37.8  235  10  5   7.0   3.9 |   2.0  35.6  195   8  4   6.7   3.7
 12500   4.2  39.6  230  12  6   6.9   3.8 |   3.0  37.4  200   8  4   7.0   3.8
 12000   5.2  41.4  230  13  7   6.8   3.8 |   4.1  39.4  205   9  4   7.2   3.9
 11500   6.2  43.2  225  14  7   6.4   3.5 |   5.2  41.4  210   9  5   6.9   3.8
 11000   7.0  44.6  220  13  7   6.1   3.3 |   6.1  43.0  220   9  5   6.5   3.6
 10500   7.8  46.0  215  11  6   3.5   1.9 |   7.1  44.8  225   9  5   4.2   2.3
 10250   8.0  46.4  215  11  6   3.0   1.6 |   7.3  45.1  225   9  5   3.8   2.1
 10000   8.2  46.8  205   9  5   5.8   3.2 |   7.8  46.0  225   8  4   8.3   4.6
  9750   8.6  47.5  190   8  4   6.0   3.3 |   8.4  47.1  225   8  4   9.0   4.9
  9500   8.9  48.0  175   7  4   6.4   3.5 |   9.0  48.2  225   7  4   6.3   3.4
  9250   9.4  48.9  175   7  4   6.3   3.5 |   9.3  48.7  225   6  3   3.7   2.1
  9000   9.9  49.8  175   7  4   9.5   5.2 |   9.6  49.3  225   6  3   6.5   3.6
  8750  10.8  51.4  180   7  4  11.6   6.4 |  10.1  50.2  220   6  3   8.2   4.5
  8500  11.6  52.9  180   7  4  10.0   5.5 |  10.7  51.3  220   6  3   7.6   4.1
  8250  12.3  54.1  180   7  4   9.5   5.2 |  11.2  52.2  220   6  3   7.3   4.0
  8000  13.0  55.4  180   7  3  10.6   5.8 |  11.7  53.1  220   6  3   8.4   4.6
  7750  13.8  56.8  180   7  3  10.9   6.0 |  12.3  54.1  220   6  3   9.5   5.2
  7500  14.6  58.3  180   7  3   9.8   5.4 |  13.0  55.4  220   7  3   8.7   4.8
  7250  15.3  59.5  180   6  3  10.0   5.5 |  13.6  56.5  215   7  4   8.7   4.8
  7000  16.1  61.0  180   6  3   9.4   5.2 |  14.2  57.6  215   8  4   8.6   4.7
  6750  16.8  62.2  180   6  3   9.9   5.4 |  14.8  58.6  210   8  4   9.1   5.0
  6500  17.5  63.5  180   6  3  10.7   5.9 |  15.4  59.7  210   9  5   9.8   5.3
  6250  18.3  64.9  185   6  3  10.6   5.8 |  16.1  61.0  210   9  5   9.4   5.2
  6000  19.1  66.4  185   6  3  10.3   5.7 |  16.8  62.2  205   9  5  10.1   5.5
  5750  19.9  67.8  185   6  3  13.6   7.5 |  17.6  63.7  205   9  5  11.3   6.2
  5500  21.2  70.2  180   6  3  20.0  11.0 |  18.4  65.1  205   8  4  11.5   6.3
________________________________________________________________________________

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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