Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 021236
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0634 MDT Tuesday, September 2, 2014

This forecast is for Tuesday, September 2, 2014:

If the trigger temperature of 77.6 F/25.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 776 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14546 ft MSL (9261 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12283 ft MSL (6998 ft AGL)
Thermal soaring outlook for Wednesday 09/03.... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12684 ft MSL (7399 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 13177 ft MSL (7892 ft AGL)
Wave soaring outlook for Wednesday 09/03....... Fair

Remarks...

Sunrise/Sunset.................... 06:28:26 / 19:30:29 MDT
Total possible sunshine........... 13 hr 2 min 2 sec (782 min 2 sec)
Altitude of sun at 12:59:01 MDT... 57.96 degrees

Upper air data from rawinsonde observation taken on 09/02/2014 at 0600 MDT

Freezing level.................. 15337 ft MSL (10052 ft AGL)
Convective condensation level... 16920 ft MSL (11635 ft AGL)
Lifted condensation level....... 16310 ft MSL (11025 ft AGL)
Lifted index.................... +0.6
K index......................... -12.9

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  -66.7 -88.1   285   28   15 -14.8  -8.1   82.4 180.4    30.5      M    M
 45000  -61.5 -78.7   280   53   27   4.0   2.2   66.6 151.9    22.8      M    M
 40000  -53.3 -63.9   280   51   26   7.6   4.2   56.4 133.6    17.7      M    M
 38000  -50.7 -59.3   280   52   27   6.0   3.3   51.6 125.0    14.8      M    M
 36000  -47.0 -52.6   280   54   28   6.9   3.8   48.6 119.4    13.1      M    M
 34000  -41.6 -42.9   285   56   29   8.2   4.5   46.9 116.5    12.3      M    M
 32000  -36.7 -34.1   285   56   29   8.2   4.5   45.7 114.2    11.6      M    M
 30000  -33.2 -27.8   280   53   27   4.0   2.2   42.4 108.4     9.5      M    M
 29000  -30.9 -23.6   285   51   26   9.1   5.0   41.5 106.7     8.9      M    M
 28000  -28.2 -18.8   285   50   26   9.1   5.0   41.1 106.0     8.7      M    M
 27000  -25.4 -13.7   290   48   25   9.1   5.0   40.9 105.6     8.6      M    M
 26000  -22.7  -8.9   290   47   24   9.1   5.0   40.7 105.3     8.6      M    M
 25000  -20.0  -4.0   295   46   24   9.2   5.0   40.7 105.2     8.6      M    M
 24000  -17.4   0.7   290   44   22   8.3   4.5   40.1 104.2     8.3      M    M
 23000  -14.9   5.2   290   41   21   8.1   4.4   39.6 103.3     7.9      M    M
 22000  -13.4   7.9   290   37   19   0.2   0.1   38.0 100.4     6.7      M    M
 21000  -11.8  10.8   290   34   18   7.2   4.0   36.4  97.6     5.4      M    M
 20000  -10.5  13.1   290   31   16   6.7   3.7   34.5  94.2     3.8      M    M
 19500   -9.4  15.1   290   30   15   8.2   4.5   34.1  93.4     3.4      M    M
 19000   -8.3  17.1   285   29   15   7.8   4.3   33.8  92.8     3.2      M    M
 18500   -7.1  19.2   285   27   14   7.7   4.2   33.4  92.2     2.9      M    M
 18000   -6.0  21.2   285   26   13   7.6   4.2   33.1  91.6     2.6      M    M
 17500   -4.8  23.4   285   24   12   7.3   4.0   32.7  90.8     2.3      M    M
 17000   -3.0  26.6   285   22   11   7.8   4.3   32.1  89.8     1.9      M    M
 16500   -2.0  28.4   285   20   10   6.1   3.3   31.6  89.0     1.5      M    M
 16000   -1.1  30.0   285   19   10   6.3   3.5   31.1  87.9     0.9      M    M
 15500   -0.1  31.8   285   18    9   6.5   3.6   30.5  86.9     0.4      M    M
 15000    1.0  33.8   285   17    9   8.9   4.9   30.2  86.3     0.1      M    M
 14500    2.4  36.3   285   16    8   8.7   4.8   30.0  86.0    -0.0    761  3.9
 14000    3.7  38.7   285   15    8   8.7   4.8   29.8  85.7    -0.2    707  3.6
 13500    5.0  41.0   280   16    8   8.5   4.7   29.6  85.4    -0.4    653  3.3
 13000    6.2  43.2   275   16    8   2.7   1.5   29.4  84.9    -0.6    602  3.1
 12500    5.8  42.4   275   17    9   0.5   0.3   27.6  81.6    -2.5    600  3.0
 12000    6.4  43.5   270   18    9   9.5   5.2   26.9  80.4    -3.4    566  2.9
 11500    7.7  45.9   270   16    8   8.8   4.8   26.7  80.1    -3.6    513  2.6
 11000    9.0  48.2   275   14    7   8.8   4.8   26.6  79.8    -3.8    459  2.3
 10500   10.2  50.4   275   12    6   8.8   4.8   26.4  79.6    -4.0    406  2.1
 10250   10.9  51.6   275   12    6   8.9   4.9   26.4  79.5    -4.1    379  1.9
 10000   11.5  52.7   270   12    6   8.9   4.9   26.3  79.3    -4.2    353  1.8
  9750   12.2  54.0   265   11    6   8.9   4.9   26.2  79.2    -4.3    326  1.7
  9500   12.8  55.0   260   11    6   9.0   4.9   26.2  79.1    -4.4    299  1.5
  9250   13.5  56.3   255   11    6   8.9   4.9   26.1  79.0    -4.5    273  1.4
  9000   14.1  57.4   250   11    6   9.4   5.2   26.1  78.9    -4.6    246  1.2
  8750   14.5  58.1   245    9    5  -3.2  -1.8   25.7  78.3    -4.9    227  1.2
  8500   14.0  57.2   240    7    4   1.2   0.7   24.5  76.1    -6.1    234  1.2
  8250   14.5  58.1   230    5    3   2.1   1.1   24.3  75.8    -6.4    211  1.1
  8000   14.0  57.2   210    4    2  -6.9  -3.8   23.1  73.5    -7.7    221  1.1
  7750   13.8  56.8   205    4    2  -0.8  -0.4   22.1  71.9    -8.6    220  1.1
  7500   13.5  56.3   200    4    2  -3.7  -2.0   21.2  70.2    -9.6    219  1.1
  7250   13.1  55.6   200    5    2  -3.5  -1.9   20.2  68.3   -10.8    223  1.1
  7000   12.8  55.0   195    5    3  -6.0  -3.3   19.1  66.4   -11.9    227  1.2
  6750   12.2  54.0   195    4    2  -7.4  -4.0   17.8  64.0   -13.2    237  1.2
  6500   11.9  53.4   195    3    2   0.4   0.2   16.7  62.1   -14.3    238  1.2
  6250   12.2  54.0   190    2    1   4.5   2.5   16.3  61.3   -14.8    223  1.1
  6000   12.4  54.3   180    1    1   2.6   1.4   15.8  60.5   -15.3    208  1.1
  5750   12.7  54.9   180    1    0   5.8   3.2   15.3  59.6   -15.8    193  1.0
  5500   12.9  55.2   000    0    0  -5.1  -2.8   14.9  58.8   -16.3    178  0.9

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

           09/02/2014 at 0900 MDT          |       09/02/2014 at 1200 MDT
                                           |
K index... +3.6  LI... +3.5                | K index... -7.4  LI... +1.1
CAPE... 0.0  CIN... -0.2                   | CAPE... +2.6  CIN... -2.6
                                           |
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 -65.7 -86.3  290  40 21   1.7   0.9 | -65.7 -86.3  290  35 18   2.4   1.3
 45000 -61.8 -79.2  285  46 23   4.7   2.6 | -61.2 -78.2  290  37 19   4.5   2.5
 40000 -54.6 -66.3  290  46 24   5.7   3.2 | -54.4 -65.9  285  42 22   5.4   3.0
 38000 -51.2 -60.2  290  48 25   5.7   3.1 | -51.2 -60.2  285  41 21   5.4   3.0
 36000 -47.8 -54.0  290  50 26   5.7   3.1 | -48.0 -54.4  285  40 20   5.4   3.0
 34000 -42.9 -45.2  295  49 25   8.9   4.9 | -42.3 -44.1  285  41 21   9.1   5.0
 32000 -36.9 -34.4  295  46 24   8.9   4.9 | -36.9 -34.4  285  43 22   9.1   5.0
 30000 -32.2 -26.0  290  43 22   7.6   4.2 | -31.9 -25.4  285  42 22   8.1   4.5
 29000 -29.9 -21.8  290  42 22   7.6   4.2 | -29.4 -20.9  290  41 21   8.1   4.5
 28000 -27.6 -17.7  290  40 21   8.3   4.6 | -27.0 -16.6  290  40 21   8.2   4.5
 27000 -25.0 -13.0  285  39 20   8.8   4.8 | -24.5 -12.1  290  39 20   8.3   4.5
 26000 -22.4  -8.3  285  38 19   8.8   4.8 | -22.0  -7.6  285  38 20   8.3   4.5
 25000 -19.7  -3.5  285  37 19   8.9   4.9 | -19.5  -3.1  285  37 19   8.3   4.5
 24000 -17.6   0.3  285  35 18   6.5   3.6 | -17.4   0.7  285  36 18   6.6   3.6
 23000 -15.7   3.7  285  34 18   6.5   3.6 | -15.5   4.1  285  34 18   6.6   3.6
 22000 -13.7   7.3  285  33 17   6.6   3.6 | -13.5   7.7  285  33 17   6.7   3.6
 21000 -11.6  11.1  285  31 16   7.3   4.0 | -11.4  11.5  285  32 16   7.1   3.9
 20000  -9.4  15.1  280  29 15   7.3   4.0 |  -9.3  15.3  285  31 16   7.1   3.9
 19500  -8.3  17.1  275  28 14   7.2   4.0 |  -8.2  17.2  285  30 16   7.0   3.9
 19000  -7.2  19.0  275  26 14   7.8   4.3 |  -7.1  19.2  285  30 15   8.3   4.5
 18500  -6.0  21.2  275  25 13   7.8   4.3 |  -5.8  21.6  280  29 15   8.3   4.6
 18000  -4.9  23.2  270  24 12   7.7   4.2 |  -4.5  23.9  280  28 14   8.1   4.5
 17500  -3.8  25.2  270  22 11   6.8   3.7 |  -3.4  25.9  280  27 14   7.2   4.0
 17000  -2.8  27.0  270  20 10   6.9   3.8 |  -2.3  27.9  280  26 13   7.3   4.0
 16500  -1.8  28.8  270  19 10   5.2   2.8 |  -0.8  30.6  275  24 12   6.5   3.6
 16000  -0.8  30.6  265  17  9   5.0   2.7 |   0.2  32.4  275  22 11   6.6   3.6
 15500  -0.0  32.0  265  15  8   5.4   2.9 |   1.2  34.2  275  21 11   6.5   3.6
 15000   0.7  33.3  265  14  7   5.4   3.0 |   2.1  35.8  275  20 10   6.5   3.6
 14500   1.5  34.7  265  14  7   6.3   3.5 |   3.1  37.6  275  19 10   6.5   3.6
 14000   2.4  36.3  270  14  7   6.7   3.7 |   4.0  39.2  275  18  9   6.5   3.6
 13500   3.4  38.1  270  13  7   6.7   3.7 |   5.0  41.0  275  18  9   6.2   3.4
 13000   4.2  39.6  270  13  7   6.6   3.6 |   5.8  42.4  275  17  9   5.9   3.2
 12500   5.1  41.2  270  13  6   7.4   4.1 |   6.6  43.9  275  16  8   6.3   3.4
 12000   6.4  43.5  265  12  6   9.0   5.0 |   7.6  45.7  270  15  8   7.1   3.9
 11500   7.7  45.9  265  10  5   8.7   4.8 |   8.5  47.3  270  13  7   7.2   4.0
 11000   8.8  47.8  260   9  5   7.3   4.0 |   9.6  49.3  260  11  6   7.4   4.1
 10500   9.9  49.8  255   8  4   4.4   2.4 |  10.7  51.3  250  10  5   3.9   2.2
 10250  10.1  50.2  250   8  4   4.6   2.5 |  10.8  51.4  245  10  5   5.8   3.2
 10000  10.7  51.3  250   7  4  10.1   5.5 |  11.6  52.9  240   9  5  11.9   6.5
  9750  11.5  52.7  245   7  4  10.4   5.7 |  12.4  54.3  235   9  5  10.6   5.8
  9500  12.2  54.0  240   7  3   8.9   4.9 |  13.2  55.8  230   9  4   9.9   5.4
  9250  12.8  55.0  240   6  3   6.3   3.4 |  13.8  56.8  225   8  4   8.1   4.4
  9000  13.3  55.9  235   6  3   7.3   4.0 |  14.4  57.9  220   8  4   9.0   4.9
  8750  13.9  57.0  230   6  3   8.9   4.9 |  15.1  59.2  215   8  4  10.1   5.5
  8500  14.5  58.1  225   6  3   7.2   4.0 |  15.8  60.4  210   8  4   8.6   4.7
  8250  14.9  58.8  225   6  3   5.8   3.2 |  16.4  61.5  205   7  4   7.4   4.0
  8000  15.3  59.5  220   5  3   5.5   3.0 |  16.9  62.4  200   7  4   7.0   3.8
  7750  15.7  60.3  220   5  3   5.0   2.7 |  17.4  63.3  195   7  4   6.3   3.4
  7500  16.0  60.8  215   5  3   2.7   1.5 |  17.8  64.0  185   6  3   6.5   3.6
  7250  16.1  61.0  215   5  2   0.9   0.5 |  18.2  64.8  175   5  3   6.7   3.7
  7000  16.1  61.0  210   5  2   1.6   0.9 |  18.6  65.5  160   5  2   6.8   3.8
  6750  16.2  61.2  205   4  2   0.8   0.5 |  19.0  66.2  140   4  2   8.3   4.5
  6500  16.1  61.0  200   4  2  -1.6  -0.9 |  19.7  67.5  130   4  2  10.0   5.5
  6250  16.0  60.8  200   4  2  -0.7  -0.4 |  20.5  68.9  130   4  2  11.1   6.1
  6000  15.8  60.4  200   4  2  -6.3  -3.5 |  21.3  70.3  125   4  2   8.4   4.6
  5750  15.3  59.5  200   4  2  -0.1  -0.0 |  21.9  71.4  125   4  2  13.1   7.2
  5500  16.2  61.2  200   3  2  27.3  15.0 |  23.5  74.3  125   4  2  28.6  15.7

           09/02/2014 at 1500 MDT          |       09/02/2014 at 1800 MDT
                                           |
K index... -0.8  LI... +1.4                | K index... +18.5  LI... +0.8
CAPE... 0.0  CIN... -1.5                   | CAPE... +0.9  CIN... -2.1
                                           |
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 -65.3 -85.5  295  27 14   2.4   1.3 | -65.1 -85.2  290  19 10   2.6   1.4
 45000 -61.0 -77.8  300  32 16   4.3   2.4 | -60.4 -76.7  300  23 12   4.4   2.4
 40000 -54.4 -65.9  285  44 23   5.4   3.0 | -53.4 -64.1  290  41 21   4.9   2.7
 38000 -51.2 -60.2  280  43 22   5.3   2.9 | -50.5 -58.9  285  41 21   4.9   2.7
 36000 -48.0 -54.4  280  43 22   5.3   2.9 | -47.5 -53.5  280  41 21   4.6   2.5
 34000 -42.4 -44.3  280  43 22   9.0   4.9 | -42.5 -44.5  280  42 22   9.1   5.0
 32000 -37.0 -34.6  280  43 22   9.1   5.0 | -37.1 -34.8  280  42 22   9.0   5.0
 30000 -32.0 -25.6  280  41 21   8.3   4.5 | -32.1 -25.8  280  40 21   8.1   4.4
 29000 -29.5 -21.1  280  40 20   8.3   4.5 | -29.7 -21.5  280  39 20   8.1   4.4
 28000 -27.0 -16.6  280  38 20   8.2   4.5 | -27.3 -17.1  285  38 19   8.1   4.4
 27000 -24.6 -12.3  280  37 19   8.2   4.5 | -24.2 -11.6  285  35 18   8.1   4.5
 26000 -22.1  -7.8  285  35 18   8.2   4.5 | -21.8  -7.2  285  33 17   8.1   4.5
 25000 -19.7  -3.5  285  33 17   8.1   4.5 | -19.4  -2.9  285  31 16   7.9   4.3
 24000 -17.6   0.3  285  32 16   6.6   3.6 | -17.3   0.9  285  30 16   6.9   3.8
 23000 -15.6   3.9  285  31 16   6.6   3.6 | -15.2   4.6  285  29 15   7.0   3.8
 22000 -13.6   7.5  285  30 15   6.8   3.7 | -13.1   8.4  285  29 15   7.0   3.8
 21000 -11.4  11.5  285  29 15   7.6   4.2 | -11.0  12.2  285  29 15   7.1   3.9
 20000  -9.1  15.6  285  29 15   7.6   4.2 |  -8.9  16.0  280  30 15   7.2   4.0
 19500  -8.0  17.6  285  29 15   7.5   4.1 |  -7.8  18.0  280  30 16   7.3   4.0
 19000  -6.8  19.8  285  29 15   8.8   4.9 |  -6.7  19.9  280  31 16   7.9   4.4
 18500  -5.4  22.3  285  29 15   8.9   4.9 |  -5.6  21.9  275  31 16   7.9   4.3
 18000  -4.1  24.6  285  28 15   8.8   4.8 |  -4.4  24.1  275  31 16   7.7   4.2
 17500  -2.8  27.0  285  28 15   8.1   4.5 |  -3.4  25.9  275  31 16   7.2   4.0
 17000  -1.6  29.1  285  28 15   8.2   4.5 |  -2.3  27.9  275  31 16   7.2   4.0
 16500   0.1  32.2  285  28 15   7.0   3.8 |  -1.3  29.7  270  31 16   8.0   4.4
 16000   1.1  34.0  285  29 15   7.2   4.0 |  -0.2  31.6  270  29 15   8.1   4.4
 15500   2.0  35.6  285  29 15   5.0   2.7 |   0.9  33.6  265  27 14   8.3   4.6
 15000   2.7  36.9  285  29 15   5.3   2.9 |   2.1  35.8  265  25 13   8.4   4.6
 14500   3.5  38.3  285  29 15   6.3   3.5 |   3.3  37.9  265  23 12   8.6   4.7
 14000   4.4  39.9  280  27 14   6.8   3.7 |   5.4  41.7  265  20 10   9.3   5.1
 13500   5.3  41.5  280  26 13   8.0   4.4 |   6.8  44.2  265  19 10   8.9   4.9
 13000   6.7  44.1  280  24 12   9.1   5.0 |   8.0  46.4  265  17  9   8.5   4.7
 12500   8.0  46.4  275  22 11   9.1   5.0 |   9.3  48.7  265  15  8   8.5   4.7
 12000   9.3  48.7  275  20 10   8.7   4.8 |  10.5  50.9  260  13  7   8.4   4.6
 11500  10.6  51.1  275  18  9   8.6   4.7 |  11.8  53.2  260  11  6   8.4   4.6
 11000  11.8  53.2  275  15  8   7.7   4.2 |  13.0  55.4  255  10  5   8.0   4.4
 10500  13.0  55.4  270  12  6   4.5   2.5 |  14.3  57.7  250   8  4   5.2   2.9
 10250  13.1  55.6  270  12  6   5.0   2.8 |  14.5  58.1  250   8  4   5.9   3.2
 10000  13.8  56.8  265  10  5   9.8   5.4 |  15.2  59.4  245   7  3  10.1   5.5
  9750  14.5  58.1  255   8  4   8.8   4.8 |  15.9  60.6  240   6  3   9.2   5.1
  9500  15.1  59.2  250   7  3   8.0   4.4 |  16.6  61.9  230   5  3   8.5   4.7
  9250  15.6  60.1  240   5  3   6.4   3.5 |  17.2  63.0  220   5  2   7.5   4.1
  9000  16.0  60.8  235   4  2   7.8   4.3 |  17.8  64.0  215   4  2   8.6   4.7
  8750  16.6  61.9  225   4  2   8.6   4.7 |  18.4  65.1  205   4  2   9.2   5.1
  8500  17.2  63.0  215   3  2   8.9   4.9 |  19.1  66.4  190   4  2   8.5   4.7
  8250  17.9  64.2  210   3  1   9.6   5.3 |  19.7  67.5  180   3  2   7.2   4.0
  8000  18.6  65.5  210   3  1  10.0   5.5 |  20.2  68.4  170   3  2   7.4   4.1
  7750  19.3  66.7  215   2  1  10.4   5.7 |  20.7  69.3  165   3  2   7.6   4.2
  7500  20.1  68.2  215   2  1  10.0   5.5 |  21.2  70.2  160   3  1   8.8   4.8
  7250  20.8  69.4  215   2  1   9.8   5.4 |  21.9  71.4  160   3  1  10.4   5.7
  7000  21.6  70.9  220   2  1   9.9   5.4 |  22.7  72.9  160   3  1  10.1   5.5
  6750  22.3  72.1  220   2  1  10.2   5.6 |  23.4  74.1  160   3  1   9.8   5.4
  6500  23.1  73.6  220   2  1  10.4   5.7 |  24.1  75.4  160   2  1   9.7   5.3
  6250  23.9  75.0  220   2  1  10.8   5.9 |  24.8  76.6  160   2  1   9.9   5.4
  6000  24.7  76.5  225   2  1   9.5   5.2 |  25.6  78.1  165   2  1   9.7   5.3
  5750  25.4  77.7  225   2  1  13.1   7.2 |  26.3  79.3  165   2  1  10.4   5.7
  5500  26.8  80.2  230   2  1  24.3  13.3 |  27.1  80.8  170   2  1  12.6   6.9
________________________________________________________________________________

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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