Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260133
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1933 MDT Saturday, July 25, 2015

This forecast is for Sunday, July 26, 2015:

If the trigger temperature of 84.9 F/29.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1040 ft/min (5.3 m/s)
   Maximum height of thermals.................. 16744 ft MSL (11437 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1015 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................. 12522 ft MSL (7215 ft AGL)
Thermal soaring outlook for Monday 07/27....... Excellent

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....................... 46729 ft MSL (41422 ft AGL)
Wave soaring outlook for Monday 07/27.......... Poor

Remarks...

Sunrise/Sunset.................... 05:52:55 / 20:19:19 MDT
Total possible sunshine........... 14 hr 26 min 24 sec (866 min 24 sec)
Altitude of sun at 13:05:56 MDT... 69.58 degrees

Upper air data from numerical model forecast valid on 07/26/2015 at 0600 MDT

Freezing level.................. 16492 ft MSL (11185 ft AGL)
Convective condensation level... 15873 ft MSL (10566 ft AGL)
Lifted condensation level....... 16439 ft MSL (11133 ft AGL)
Lifted index.................... -2.8
K index......................... +24.1

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  -67.8 -90.0   245   39   20   2.2   1.2      M     M       M      M    M
 45000  -62.0 -79.6   245   51   26   7.0   3.9      M     M       M      M    M
 40000  -51.3 -60.3   250   50   25   7.8   4.3      M     M       M      M    M
 38000  -46.6 -51.9   245   47   24   7.8   4.3      M     M       M      M    M
 36000  -41.4 -42.5   245   44   23   7.9   4.3      M     M       M      M    M
 34000  -36.6 -33.9   245   41   21   7.9   4.3      M     M       M      M    M
 32000  -31.9 -25.4   250   38   20   7.8   4.3      M     M       M      M    M
 30000  -27.6 -17.7   250   35   18   7.1   3.9   48.4 119.1    11.1      M    M
 29000  -25.5 -13.9   250   34   17   7.1   3.9   47.4 117.4    10.4      M    M
 28000  -23.4 -10.1   250   32   16   6.2   3.4   46.4 115.6     9.8      M    M
 27000  -21.5  -6.7   250   28   15   6.2   3.4   45.0 112.9     8.8      M    M
 26000  -19.7  -3.5   245   25   13   6.2   3.4   43.6 110.6     7.8      M    M
 25000  -17.8  -0.0   245   22   11   6.6   3.6   42.5 108.4     6.9      M    M
 24000  -15.6   3.9   245   21   11   7.3   4.0   41.4 106.6     6.2      M    M
 23000  -13.4   7.9   245   20   10   7.3   4.0   40.5 104.9     5.5      M    M
 22000  -11.2  11.8   245   20   10   7.2   3.9   39.7 103.5     4.9      M    M
 21000   -9.1  15.6   245   19   10   7.0   3.8   38.6 101.6     4.0      M    M
 20000   -7.0  19.4   250   19   10   7.0   3.8   37.7  99.8     3.3      M    M
 19500   -6.0  21.2   250   18    9   7.0   3.9   37.3  99.1     2.9      M    M
 19000   -5.0  23.0   250   18    9   6.7   3.7   36.8  98.2     2.5      M    M
 18500   -4.0  24.8   250   18    9   6.7   3.7   36.2  97.2     2.0      M    M
 18000   -2.5  27.5   245   17    9   6.2   3.4   35.4  95.7     1.3      M    M
 17500   -1.6  29.1   245   17    9   6.3   3.5   34.8  94.6     0.7      M    M
 17000   -0.7  30.7   245   16    8   6.3   3.4   34.2  93.6     0.2      M    M
 16500    0.2  32.4   245   15    8   6.4   3.5   33.6  92.5    -0.4   1012  5.1
 16000    1.0  33.8   240   15    8   6.7   3.7   33.1  91.6    -1.1    972  4.9
 15500    1.9  35.4   240   15    8   6.8   3.7   32.6  90.6    -1.7    932  4.7
 15000    2.7  36.9   235   14    7   6.9   3.8   32.1  89.8    -2.3    890  4.5
 14500    3.8  38.8   235   14    7  10.1   5.5   31.8  89.3    -2.7    843  4.3
 14000    5.3  41.5   230   13    7  10.3   5.7   31.9  89.5    -2.7    784  4.0
 13500    6.8  44.2   230   12    6   9.6   5.3   32.0  89.6    -2.7    725  3.7
 13000    8.1  46.6   225   11    6   9.3   5.1   31.9  89.5    -2.9    671  3.4
 12500    9.4  48.9   215   11    5   8.9   4.9   31.9  89.3    -3.0    617  3.1
 12000   10.6  51.1   210   10    5   8.5   4.7   31.6  89.0    -3.3    565  2.9
 11500   11.9  53.4   200    9    5   8.8   4.8   31.5  88.6    -3.5    513  2.6
 11000   13.2  55.8   190    9    4   9.0   4.9   31.4  88.5    -3.6    457  2.3
 10500   14.6  58.3   185    8    4   4.7   2.6   31.3  88.4    -3.7    402  2.0
 10250   14.8  58.6   185    8    4   5.4   3.0   30.7  87.3    -4.3    389  2.0
 10000   15.5  59.9   185    7    4  11.6   6.4   30.8  87.4    -4.3    359  1.8
  9750   16.3  61.3   185    7    4  10.4   5.7   30.8  87.5    -4.2    328  1.7
  9500   17.1  62.8   180    6    3   9.1   5.0   30.9  87.6    -4.2    298  1.5
  9250   17.6  63.7   180    6    3   6.9   3.8   30.7  87.3    -4.4    274  1.4
  9000   18.2  64.8   180    5    2   8.2   4.5   30.5  87.0    -4.6    250  1.3
  8750   18.8  65.8   180    4    2   9.2   5.1   30.5  86.8    -4.7    223  1.1
  8500   19.5  67.1   185    3    1   8.1   4.4   30.4  86.7    -4.8    196  1.0
  8250   20.0  68.0   195    2    1   7.1   3.9   30.2  86.4    -4.9    172  0.9
  8000   20.6  69.1   220    1    1   6.6   3.6   30.0  86.0    -5.1    148  0.8
  7750   21.1  70.0   265    1    1   5.8   3.2   29.7  85.5    -5.4    126  0.6
  7500   21.5  70.7   295    1    1   6.5   3.6   29.4  85.0    -5.7    105  0.5
  7250   22.1  71.8   305    2    1   7.0   3.9   29.2  84.6    -5.9     81  0.4
  7000   22.6  72.7   305    3    1   7.1   3.9   29.0  84.2    -6.1     58  0.3
  6750   23.1  73.6   305    4    2   6.2   3.4   28.8  83.8    -6.3     34  0.2
  6500   23.5  74.3   305    4    2   3.6   2.0   28.4  83.1    -6.7     16  0.1
  6250   23.6  74.5   305    4    2   0.3   0.2   27.8  82.1    -7.3      6  0.0
  6000   23.7  74.7   305    4    2   7.5   4.1   27.2  81.0    -8.0      M    M
  5750   24.2  75.6   310    5    3  -1.9  -1.1   27.1  80.7    -8.2      M    M
  5500   22.3  72.1   285    3    2 -42.0 -23.1   24.7  76.5   -10.8     22  0.1

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

           07/26/2015 at 0900 MDT          |       07/26/2015 at 1200 MDT
                                           |
K index... +17.6  LI... -1.8               | K index... +26.1  LI... -1.1
CAPE... +269.0  CIN... -36.9               | CAPE... +41.4  CIN... -16.3
                                           |
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 -67.5 -89.5  245  38 20   1.8   1.0 | -67.4 -89.3  240  39 20   2.3   1.2
 45000 -62.2 -80.0  245  51 26   6.9   3.8 | -61.8 -79.2  240  53 27   6.7   3.7
 40000 -51.6 -60.9  240  52 27   7.8   4.3 | -51.2 -60.2  240  55 28   7.2   4.0
 38000 -46.9 -52.4  240  51 26   7.8   4.3 | -46.8 -52.2  235  54 28   7.2   4.0
 36000 -41.6 -42.9  240  50 26   7.6   4.2 | -42.5 -44.5  235  53 27   7.9   4.3
 34000 -37.0 -34.6  240  47 24   7.5   4.1 | -37.4 -35.3  235  47 24   8.5   4.6
 32000 -32.5 -26.5  235  44 23   8.4   4.6 | -32.4 -26.3  230  42 22   9.3   5.1
 30000 -28.1 -18.6  240  39 20   7.4   4.0 | -27.8 -18.0  225  35 18   7.7   4.2
 29000 -25.9 -14.6  240  36 19   7.4   4.0 | -25.5 -13.9  225  31 16   7.7   4.2
 28000 -23.8 -10.8  240  33 17   6.0   3.3 | -22.8  -9.0  225  27 14   6.5   3.6
 27000 -22.0  -7.6  240  30 15   6.1   3.3 | -20.8  -5.4  225  24 12   6.6   3.6
 26000 -20.2  -4.4  240  26 13   6.1   3.3 | -18.9  -2.0  225  21 11   6.6   3.6
 25000 -18.3  -0.9  240  22 11   6.4   3.5 | -16.9   1.6  225  18  9   6.4   3.5
 24000 -16.3   2.7  235  21 11   7.0   3.8 | -15.1   4.8  220  17  9   6.2   3.4
 23000 -14.2   6.4  230  21 11   7.0   3.8 | -13.3   8.1  215  17  9   6.2   3.4
 22000 -12.1  10.2  230  20 10   7.0   3.8 | -11.5  11.3  205  16  8   5.9   3.2
 21000 -10.0  14.0  230  19 10   6.9   3.8 |  -9.8  14.4  205  16  8   5.7   3.1
 20000  -7.9  17.8  235  19 10   6.9   3.8 |  -8.2  17.2  205  16  8   5.8   3.2
 19500  -6.8  19.8  240  18  9   6.9   3.8 |  -7.4  18.7  205  16  8   5.8   3.2
 19000  -5.8  21.6  240  18  9   7.5   4.1 |  -6.5  20.3  205  16  8   6.4   3.5
 18500  -4.1  24.6  240  18  9   7.5   4.1 |  -5.6  21.9  200  15  8   6.4   3.5
 18000  -3.0  26.6  240  18  9   7.6   4.2 |  -4.6  23.7  200  15  8   6.7   3.7
 17500  -1.9  28.6  240  18  9   7.6   4.2 |  -3.6  25.5  200  15  8   6.9   3.8
 17000  -0.8  30.6  235  17  9   7.6   4.2 |  -2.6  27.3  205  14  7   6.9   3.8
 16500   0.4  32.7  235  16  8   7.5   4.1 |  -1.8  28.8  200  14  7   5.1   2.8
 16000   1.5  34.7  230  14  7   7.5   4.1 |  -1.0  30.2  200  14  7   5.1   2.8
 15500   2.6  36.7  230  12  6   6.9   3.8 |  -0.2  31.6  200  14  7   7.1   3.9
 15000   3.6  38.5  225  11  6   6.9   3.8 |   1.5  34.7  200  12  6   7.0   3.8
 14500   4.7  40.5  225  10  5   8.6   4.7 |   2.8  37.0  205  12  6  10.4   5.7
 14000   5.9  42.6  220  10  5   8.7   4.8 |   4.3  39.7  210  11  6  10.1   5.6
 13500   7.1  44.8  215   9  5   8.9   4.9 |   5.8  42.4  215  11  6   9.6   5.3
 13000   8.3  46.9  210   9  4   9.1   5.0 |   7.3  45.1  220  11  6   9.5   5.2
 12500   9.6  49.3  205   8  4   9.0   4.9 |   8.7  47.7  225  11  6   9.0   4.9
 12000  10.8  51.4  205   7  4   8.9   4.9 |  10.0  50.0  230  11  6   8.7   4.8
 11500  12.0  53.6  200   7  4   8.9   4.9 |  11.2  52.2  235  12  6   9.0   5.0
 11000  13.2  55.8  195   6  3   8.5   4.7 |  12.6  54.7  235  12  6   9.0   4.9
 10500  14.5  58.1  190   5  3   3.8   2.1 |  14.1  57.4  240  11  6   4.7   2.6
 10250  14.6  58.3  190   5  3   5.0   2.8 |  14.2  57.6  240  11  6   6.5   3.6
 10000  15.4  59.7  190   5  2  12.2   6.7 |  15.1  59.2  240  11  6  13.5   7.4
  9750  16.2  61.2  190   4  2  11.0   6.0 |  16.0  60.8  240  11  5  12.4   6.8
  9500  16.9  62.4  190   3  2   8.9   4.9 |  16.9  62.4  240  10  5   9.8   5.4
  9250  17.4  63.3  190   2  1   6.0   3.3 |  17.4  63.3  240  10  5   7.7   4.2
  9000  18.0  64.4  200   1  1   7.5   4.1 |  18.1  64.6  245  10  5  10.3   5.6
  8750  18.6  65.5  235   1  0   8.3   4.6 |  18.8  65.8  245   9  5  10.7   5.9
  8500  19.2  66.6  295   1  0   7.4   4.1 |  19.6  67.3  245   9  5   9.6   5.3
  8250  19.7  67.5  310   2  1   6.7   3.7 |  20.2  68.4  245   8  4   8.7   4.8
  8000  20.3  68.5  315   2  1   6.7   3.7 |  20.9  69.6  250   8  4   8.9   4.9
  7750  20.8  69.4  320   3  1   6.4   3.5 |  21.5  70.7  250   7  4   8.9   4.9
  7500  21.3  70.3  320   3  2   6.8   3.7 |  22.2  72.0  255   7  3   9.6   5.3
  7250  21.9  71.4  320   4  2   6.9   3.8 |  22.9  73.2  255   6  3  10.0   5.5
  7000  22.4  72.3  315   4  2   7.2   3.9 |  23.6  74.5  260   6  3   9.7   5.3
  6750  23.0  73.4  315   5  2   7.2   3.9 |  24.3  75.7  260   6  3   9.8   5.4
  6500  23.4  74.1  310   5  2   5.2   2.9 |  25.1  77.2  260   6  3  10.3   5.7
  6250  23.7  74.7  315   5  2   5.4   3.0 |  25.9  78.6  260   6  3  11.0   6.0
  6000  24.1  75.4  315   5  2   2.2   1.2 |  26.6  79.9  260   6  3   9.0   4.9
  5750  24.1  75.4  315   5  2   4.9   2.7 |  27.4  81.3  260   5  3  12.1   6.7
  5500  24.9  76.8  310   4  2  20.3  11.1 |  28.6  83.5  260   5  3  22.9  12.6

           07/26/2015 at 1500 MDT          |       07/26/2015 at 1800 MDT
                                           |
K index... +24.9  LI... +0.4               | K index... +26.0  LI... -1.9
CAPE... 0.0  CIN... M                      | CAPE... +95.4  CIN... -38.6
                                           |
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 -67.5 -89.5  240  38 19   2.4   1.3 | -67.7 -89.9  240  37 19   2.6   1.4
 45000 -61.7 -79.1  240  51 26   6.8   3.7 | -61.6 -78.9  235  48 25   6.9   3.8
 40000 -50.9 -59.6  235  53 27   7.5   4.1 | -50.6 -59.1  230  51 26   7.5   4.1
 38000 -46.4 -51.5  235  51 26   7.5   4.1 | -46.1 -51.0  230  51 26   7.5   4.1
 36000 -41.9 -43.4  235  49 25   7.7   4.2 | -41.5 -42.7  230  51 26   7.8   4.3
 34000 -37.1 -34.8  230  46 24   8.0   4.4 | -36.7 -34.1  230  48 25   8.0   4.4
 32000 -32.3 -26.1  230  43 22   8.8   4.8 | -31.9 -25.4  230  45 23   8.8   4.8
 30000 -27.1 -16.8  230  39 20   7.9   4.3 | -27.2 -17.0  225  41 21   7.9   4.3
 29000 -24.7 -12.5  230  37 19   7.9   4.3 | -24.3 -11.7  225  39 20   7.9   4.4
 28000 -22.5  -8.5  230  35 18   7.0   3.8 | -22.1  -7.8  225  36 18   6.8   3.7
 27000 -20.4  -4.7  235  33 17   7.1   3.9 | -20.1  -4.2  225  32 16   6.9   3.8
 26000 -18.3  -0.9  235  32 17   7.1   3.9 | -18.1  -0.6  225  28 14   6.9   3.8
 25000 -16.2   2.8  235  31 16   6.7   3.7 | -16.1   3.0  230  24 12   6.5   3.6
 24000 -14.4   6.1  235  29 15   6.3   3.5 | -14.3   6.3  230  21 11   6.2   3.4
 23000 -12.6   9.3  240  28 14   6.4   3.5 | -12.5   9.5  235  17  9   6.2   3.4
 22000 -10.7  12.7  245  26 13   6.1   3.4 | -10.7  12.7  240  14  7   5.9   3.2
 21000  -9.0  15.8  240  25 13   6.0   3.3 |  -9.1  15.6  240  12  6   5.7   3.1
 20000  -7.2  19.0  240  25 13   6.0   3.3 |  -7.4  18.7  240   9  4   5.7   3.1
 19500  -6.4  20.5  235  24 13   6.0   3.3 |  -6.6  20.1  245   7  4   5.8   3.2
 19000  -5.5  22.1  235  24 12   6.0   3.3 |  -5.8  21.6  245   6  3   4.9   2.7
 18500  -4.6  23.7  235  22 12   6.0   3.3 |  -5.1  22.8  255   5  3   5.0   2.8
 18000  -3.7  25.3  240  21 11   6.5   3.6 |  -4.3  24.3  265   4  2   6.4   3.5
 17500  -2.7  27.1  240  20 10   6.8   3.7 |  -3.2  26.2  280   4  2   7.4   4.1
 17000  -1.7  28.9  245  19 10   6.8   3.7 |  -2.1  28.2  290   4  2   7.5   4.1
 16500  -0.6  30.9  245  18  9   8.2   4.5 |  -0.8  30.6  285   3  2   9.8   5.4
 16000   0.6  33.1  245  17  9   8.0   4.4 |   0.6  33.1  265   3  2   9.6   5.3
 15500   2.4  36.3  245  16  8   8.4   4.6 |   2.7  36.9  235   4  2   9.0   5.0
 15000   3.6  38.5  245  16  8   8.4   4.6 |   4.0  39.2  225   5  3   9.1   5.0
 14500   4.9  40.8  240  15  8   8.0   4.4 |   5.3  41.5  220   6  3   9.0   4.9
 14000   6.0  42.8  240  15  8   8.1   4.4 |   6.6  43.9  215   7  4   9.0   4.9
 13500   7.2  45.0  240  15  8   8.0   4.4 |   7.9  46.2  215   9  4   8.6   4.7
 13000   8.4  47.1  235  16  8   8.0   4.4 |   9.2  48.6  215   9  5   8.5   4.7
 12500   9.6  49.3  235  16  8   8.1   4.4 |  10.5  50.9  215  10  5   8.5   4.7
 12000  10.8  51.4  235  16  8   8.2   4.5 |  11.7  53.1  215  12  6   8.6   4.7
 11500  12.0  53.6  230  17  9   8.3   4.6 |  12.9  55.2  215  13  7   8.7   4.8
 11000  13.3  55.9  230  17  9   8.3   4.5 |  14.2  57.6  215  14  7   8.6   4.7
 10500  14.5  58.1  225  17  9   4.5   2.5 |  15.5  59.9  215  14  7   5.3   2.9
 10250  14.7  58.5  225  17  9   5.5   3.0 |  15.8  60.4  215  14  7   6.2   3.4
 10000  15.4  59.7  225  17  9  11.2   6.2 |  16.5  61.7  210  15  7  11.3   6.2
  9750  16.2  61.2  220  16  8  10.1   5.5 |  17.3  63.1  210  15  8  10.3   5.7
  9500  16.9  62.4  220  16  8   9.0   4.9 |  18.0  64.4  210  15  8   9.2   5.1
  9250  17.5  63.5  220  16  8   7.3   4.0 |  18.6  65.5  205  15  8   7.6   4.2
  9000  18.0  64.4  215  15  8   8.2   4.5 |  19.2  66.6  205  15  8   8.6   4.7
  8750  18.7  65.7  215  14  7   8.1   4.5 |  19.8  67.6  205  14  7   8.8   4.8
  8500  19.3  66.7  210  13  7   9.0   4.9 |  20.5  68.9  200  14  7   8.9   4.9
  8250  20.0  68.0  210  12  6   9.9   5.5 |  21.1  70.0  200  14  7   9.1   5.0
  8000  20.7  69.3  210  12  6  10.0   5.5 |  21.8  71.2  195  13  7   9.2   5.0
  7750  21.5  70.7  210  11  6  10.4   5.7 |  22.4  72.3  195  13  7   9.0   4.9
  7500  22.2  72.0  210  11  6   9.9   5.4 |  23.1  73.6  195  13  7   9.8   5.4
  7250  23.0  73.4  210  11  6   9.4   5.2 |  23.9  75.0  195  13  6  10.8   5.9
  7000  23.7  74.7  210  11  6   9.7   5.3 |  24.7  76.5  195  12  6  10.2   5.6
  6750  24.4  75.9  210  11  5  10.3   5.7 |  25.4  77.7  195  12  6   9.7   5.3
  6500  25.2  77.4  210  11  5  10.6   5.8 |  26.1  79.0  195  12  6  10.1   5.5
  6250  26.1  79.0  210  10  5  11.2   6.1 |  26.9  80.4  195  12  6  10.9   6.0
  6000  26.9  80.4  210  10  5   9.4   5.2 |  27.7  81.9  195  11  6   9.8   5.4
  5750  27.6  81.7  210  10  5  12.0   6.6 |  28.4  83.1  195  11  6  10.4   5.7
  5500  28.8  83.8  210   9  5  22.5  12.4 |  29.3  84.7  195  10  5  15.6   8.6
________________________________________________________________________________

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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