Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260109
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1909 MDT Tuesday, August 25, 2015

This forecast is for Wednesday, August 26, 2015:

If the trigger temperature of 86.3 F/30.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1100 ft/min (5.6 m/s)
   Maximum height of thermals.................. 17194 ft MSL (11887 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12306 ft MSL (6999 ft AGL)
Thermal soaring outlook for Thursday 08/27..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT).........
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18380 ft MSL (13073 ft AGL)
Wave soaring outlook for Thursday 08/27........ Poor

Remarks...

Sunrise/Sunset.................... 06:21:40 / 19:41:34 MDT
Total possible sunshine........... 13 hr 19 min 54 sec (799 min 54 sec)
Altitude of sun at 13:01:13 MDT... 60.55 degrees

Upper air data from numerical model forecast valid on 08/26/2015 at 0600 MDT

Freezing level.................. 16724 ft MSL (11417 ft AGL)
Convective condensation level... 17916 ft MSL (12609 ft AGL)
Lifted condensation level....... 17936 ft MSL (12629 ft AGL)
Lifted index.................... -2.5
K index......................... +23.0

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -65.3 -85.5   315   29   15   2.4   1.3      M     M       M      M    M
 45000  -61.1 -78.0   305   47   24   3.5   1.9      M     M       M      M    M
 40000  -54.9 -66.8   300   63   33   8.1   4.5      M     M       M      M    M
 38000  -50.0 -58.0   300   56   29   8.2   4.5      M     M       M      M    M
 36000  -44.5 -48.1   305   48   25   8.3   4.5      M     M       M      M    M
 34000  -39.5 -39.1   305   37   19   8.3   4.6      M     M       M      M    M
 32000  -34.5 -30.1   310   27   14   8.5   4.7      M     M       M      M    M
 30000  -30.1 -22.2   305   20   10   7.3   4.0   45.4 113.7     8.3      M    M
 29000  -27.9 -18.2   300   17    9   7.3   4.0   44.5 112.2     7.7      M    M
 28000  -25.8 -14.4   295   14    7   7.1   3.9   43.7 110.6     7.1      M    M
 27000  -23.6 -10.5   290   10    5   7.1   3.9   42.5 108.6     6.3      M    M
 26000  -21.5  -6.7   280    7    4   7.1   3.9   41.6 106.8     5.6      M    M
 25000  -19.4  -2.9   260    5    2   7.2   4.0   40.7 105.2     4.9      M    M
 24000  -17.2   1.0   225    4    2   7.4   4.0   39.7 103.4     4.1      M    M
 23000  -15.0   5.0   195    6    3   7.4   4.1   38.8 101.9     3.4      M    M
 22000  -12.9   8.8   185    8    4   7.5   4.1   38.1 100.6     2.7      M    M
 21000  -10.6  12.9   195    9    5   7.5   4.1   37.2  99.0     2.0      M    M
 20000   -8.4  16.9   200   11    5   7.5   4.1   36.4  97.6     1.3      M    M
 19500   -7.3  18.9   205   11    6   7.7   4.2   36.1  97.0     1.0      M    M
 19000   -6.1  21.0   205   12    6   8.1   4.5   35.8  96.4     0.7      M    M
 18500   -4.3  24.3   200   13    7   8.3   4.5   35.4  95.7     0.3      M    M
 18000   -3.0  26.6   200   14    7   9.2   5.0   35.2  95.4     0.2      M    M
 17500   -1.7  28.9   200   14    7   9.2   5.1   35.1  95.2     0.0      M    M
 17000   -0.4  31.3   200   14    7   8.0   4.4   34.9  94.9    -0.1   1068  5.4
 16500    0.7  33.3   200   15    8   7.8   4.3   34.6  94.3    -0.5   1019  5.2
 16000    1.9  35.4   200   15    8   7.8   4.3   34.3  93.7    -0.8    970  4.9
 15500    3.0  37.4   200   15    8   7.9   4.3   34.0  93.1    -1.1    921  4.7
 15000    4.2  39.6   200   15    8   7.9   4.4   33.7  92.6    -1.4    871  4.4
 14500    5.3  41.5   205   15    8   7.6   4.1   33.3  92.0    -1.7    822  4.2
 14000    6.4  43.5   210   15    8   7.5   4.1   33.0  91.4    -2.1    774  3.9
 13500    7.6  45.7   215   15    8   8.2   4.5   32.7  90.8    -2.4    725  3.7
 13000    8.8  47.8   215   15    8   8.3   4.5   32.4  90.4    -2.7    674  3.4
 12500   10.0  50.0   220   15    8   8.8   4.8   32.2  90.0    -2.9    623  3.2
 12000   11.3  52.3   220   16    8   9.0   4.9   32.1  89.8    -3.1    568  2.9
 11500   12.7  54.9   220   17    9   8.9   4.9   32.0  89.5    -3.3    514  2.6
 11000   14.0  57.2   225   17    9   8.8   4.9   31.8  89.3    -3.4    459  2.3
 10500   15.2  59.4   225   18    9   3.7   2.1   31.6  88.9    -3.7    408  2.1
 10250   15.4  59.7   225   18    9   6.6   3.6   31.0  87.9    -4.2    394  2.0
 10000   16.3  61.3   225   18    9  12.9   7.1   31.2  88.1    -4.1    361  1.8
  9750   17.1  62.8   225   17    9  11.3   6.2   31.3  88.4    -4.0    328  1.7
  9500   17.9  64.2   225   17    9   8.4   4.6   31.4  88.5    -3.9    297  1.5
  9250   18.4  65.1   225   17    9   6.7   3.7   31.2  88.1    -4.2    274  1.4
  9000   19.0  66.2   225   18    9  10.1   5.6   31.1  87.9    -4.3    248  1.3
  8750   19.8  67.6   225   18    9  10.9   6.0   31.2  88.1    -4.2    217  1.1
  8500   20.6  69.1   225   18    9   8.9   4.9   31.2  88.1    -4.2    187  1.0
  8250   21.2  70.2   225   18    9   7.8   4.3   31.0  87.9    -4.3    161  0.8
  8000   21.8  71.2   225   18    9   8.6   4.7   30.9  87.7    -4.5    136  0.7
  7750   22.5  72.5   225   19   10   8.9   4.9   30.9  87.6    -4.5    108  0.5
  7500   23.1  73.6   225   19   10   8.5   4.6   30.8  87.4    -4.6     81  0.4
  7250   23.8  74.8   225   19   10   7.8   4.3   30.7  87.2    -4.7     55  0.3
  7000   24.4  75.9   225   19   10   9.8   5.4   30.5  87.0    -4.9     29  0.1
  6750   25.1  77.2   225   19   10   6.2   3.4   30.5  86.9    -4.9      1  0.0
  6500   25.2  77.4   230   19   10  -0.8  -0.4   29.9  85.8    -5.6      M    M
  6250   25.2  77.4   230   18    9   4.0   2.2   29.2  84.6    -6.3      M    M
  6000   25.2  77.4   235   17    9 -11.8  -6.4   28.5  83.3    -7.0      M    M
  5750   23.1  73.6   230   15    8 -34.1 -18.7   25.8  78.5    -9.9     31  0.2
  5500   20.6  69.1   220   11    5 -24.5 -13.4   22.7  72.9   -13.1     98  0.5

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

           08/26/2015 at 0900 MDT          |       08/26/2015 at 1200 MDT
                                           |
K index... +24.1  LI... -0.3               | K index... +21.6  LI... -1.7
CAPE... +40.0  CIN... -98.0                | CAPE... +268.1  CIN... -68.5
                                           |
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 -65.1 -85.2  310  28 14   2.9   1.6 | -65.7 -86.3  310  32 16   3.2   1.8
 45000 -60.6 -77.1  300  44 23   3.2   1.7 | -60.4 -76.7  300  47 24   3.7   2.1
 40000 -54.5 -66.1  300  54 28   7.7   4.2 | -53.8 -64.8  290  58 30   7.6   4.2
 38000 -49.9 -57.8  300  44 23   7.7   4.2 | -49.3 -56.7  290  43 22   7.6   4.2
 36000 -45.3 -49.5  295  34 18   8.4   4.6 | -44.8 -48.6  290  29 15   8.2   4.5
 34000 -39.8 -39.6  295  27 14   9.3   5.1 | -39.5 -39.1  290  22 11   8.8   4.9
 32000 -34.2 -29.6  300  19 10   9.8   5.4 | -34.2 -29.6  295  15  8   9.4   5.1
 30000 -30.0 -22.0  290  14  7   6.9   3.8 | -28.9 -20.0  280  12  6   7.7   4.2
 29000 -27.5 -17.5  285  11  6   6.9   3.8 | -26.7 -16.1  270  11  6   7.7   4.2
 28000 -25.4 -13.7  275  10  5   7.1   3.9 | -24.5 -12.1  255  11  6   6.5   3.6
 27000 -23.3  -9.9  270   9  5   7.1   3.9 | -22.6  -8.7  245  11  6   6.6   3.6
 26000 -21.2  -6.2  260   8  4   7.1   3.9 | -20.6  -5.1  230  12  6   6.6   3.6
 25000 -19.0  -2.2  255   7  4   7.4   4.0 | -18.7  -1.7  225  13  7   6.8   3.7
 24000 -16.9   1.6  240   7  3   7.4   4.1 | -16.7   1.9  220  12  6   6.9   3.8
 23000 -14.7   5.5  225   7  4   7.5   4.1 | -14.6   5.7  215  11  6   6.9   3.8
 22000 -12.5   9.5  215   7  4   7.2   3.9 | -12.6   9.3  215  10  5   7.3   4.0
 21000 -10.4  13.3  220   8  4   7.2   4.0 | -10.4  13.3  220  11  5   7.4   4.0
 20000  -8.4  16.9  225   9  5   7.3   4.0 |  -8.3  17.1  225  11  5   7.4   4.0
 19500  -7.3  18.9  225  10  5   7.6   4.2 |  -7.2  19.0  225  11  6   7.6   4.2
 19000  -6.2  20.8  225  12  6   7.9   4.4 |  -6.0  21.2  225  11  6   7.9   4.3
 18500  -5.0  23.0  225  14  7   7.9   4.3 |  -4.8  23.4  230  12  6   7.9   4.3
 18000  -3.8  25.2  230  15  8   8.2   4.5 |  -3.6  25.5  230  13  7   8.2   4.5
 17500  -2.6  27.3  230  17  9   8.2   4.5 |  -2.4  27.7  230  13  7   8.2   4.5
 17000  -1.3  29.7  230  18  9   8.2   4.5 |  -1.2  29.8  230  14  7   8.3   4.6
 16500  -0.1  31.8  225  19 10   8.2   4.5 |   0.0  32.0  230  15  8   8.5   4.6
 16000   1.1  34.0  225  19 10   8.2   4.5 |   1.3  34.3  230  16  8   8.5   4.7
 15500   2.3  36.1  225  20 10   8.6   4.7 |   3.1  37.6  225  17  9   8.3   4.5
 15000   4.2  39.6  220  20 10   8.5   4.7 |   4.3  39.7  225  18  9   8.3   4.5
 14500   5.4  41.7  220  20 10   8.3   4.6 |   5.5  41.9  225  18  9   8.3   4.5
 14000   6.6  43.9  220  20 10   8.3   4.6 |   6.7  44.1  220  19 10   8.3   4.5
 13500   7.8  46.0  220  19 10   8.3   4.5 |   7.9  46.2  220  19 10   8.3   4.6
 13000   9.1  48.4  220  18  9   8.2   4.5 |   9.1  48.4  220  19 10   8.3   4.6
 12500  10.3  50.5  220  17  9   8.9   4.9 |  10.3  50.5  215  19 10   8.4   4.6
 12000  11.6  52.9  220  17  9   8.9   4.9 |  11.6  52.9  215  18  9   8.5   4.6
 11500  12.9  55.2  220  16  8   8.8   4.8 |  12.8  55.0  215  18  9   8.6   4.7
 11000  14.1  57.4  220  15  8   9.0   4.9 |  14.1  57.4  215  17  9   8.8   4.8
 10500  15.2  59.4  220  14  7   3.8   2.1 |  15.2  59.4  210  16  8   4.2   2.3
 10250  15.5  59.9  220  14  7   7.3   4.0 |  15.5  59.9  210  15  8   7.7   4.2
 10000  16.3  61.3  225  13  7  12.4   6.8 |  16.3  61.3  210  14  7  12.3   6.8
  9750  17.2  63.0  225  13  7  10.7   5.9 |  17.1  62.8  210  13  7  10.7   5.9
  9500  17.9  64.2  225  12  6   8.3   4.6 |  17.8  64.0  210  12  6   7.6   4.1
  9250  18.4  65.1  225  12  6   7.2   4.0 |  18.3  64.9  210  12  6   6.8   3.8
  9000  19.1  66.4  230  12  6   9.2   5.1 |  18.9  66.0  210  11  6  10.0   5.5
  8750  19.8  67.6  230  11  6   9.4   5.1 |  19.7  67.5  210  10  5  10.2   5.6
  8500  20.4  68.7  235  11  6   8.3   4.6 |  20.4  68.7  210   9  4   9.0   5.0
  8250  21.0  69.8  235  11  6   7.9   4.3 |  21.0  69.8  210   8  4   8.4   4.6
  8000  21.6  70.9  240  10  5   8.3   4.5 |  21.6  70.9  205   6  3   9.4   5.2
  7750  22.3  72.1  240  10  5   7.8   4.3 |  22.3  72.1  205   6  3  10.3   5.7
  7500  22.8  73.0  240  10  5   7.2   3.9 |  23.1  73.6  205   6  3  10.1   5.6
  7250  23.3  73.9  240  10  5   6.4   3.5 |  23.8  74.8  205   5  3  10.1   5.5
  7000  23.8  74.8  245  10  5   8.9   4.9 |  24.6  76.3  205   5  3  10.5   5.8
  6750  24.5  76.1  245  10  5   4.8   2.6 |  25.4  77.7  205   5  3  10.6   5.8
  6500  24.5  76.1  245  10  5  -1.2  -0.7 |  26.1  79.0  205   5  3  10.3   5.6
  6250  24.5  76.1  245  10  5   1.3   0.7 |  26.9  80.4  205   5  2  10.0   5.5
  6000  24.4  75.9  245  10  5  -3.6  -2.0 |  27.6  81.7  205   5  2  11.4   6.3
  5750  23.9  75.0  240   8  4  -4.4  -2.4 |  28.7  83.7  205   5  2  17.1   9.4
  5500  23.9  75.0  225   6  3   7.5   4.1 |  30.1  86.2  210   5  2  22.0  12.1

           08/26/2015 at 1500 MDT          |       08/26/2015 at 1800 MDT
                                           |
K index... +17.0  LI... -1.7               | K index... +24.6  LI... -0.7
CAPE... +204.9  CIN... -33.4               | CAPE... +75.4  CIN... -21.1
                                           |
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 -66.1 -87.0  310  34 17   3.0   1.7 | -66.4 -87.5  310  36 18   2.2   1.2
 45000 -61.1 -78.0  300  47 24   4.0   2.2 | -61.7 -79.1  300  47 24   4.6   2.5
 40000 -53.6 -64.5  285  52 27   8.8   4.8 | -53.6 -64.5  280  40 21   9.2   5.1
 38000 -48.3 -54.9  280  47 24   8.8   4.8 | -48.1 -54.6  280  34 17   9.2   5.1
 36000 -43.1 -45.6  280  41 21   8.4   4.6 | -42.6 -44.7  275  27 14   9.0   4.9
 34000 -38.3 -36.9  280  30 15   8.1   4.4 | -37.3 -35.1  275  24 12   8.8   4.8
 32000 -33.4 -28.1  285  18  9   8.7   4.8 | -32.0 -25.6  275  22 11   9.6   5.3
 30000 -28.1 -18.6  270  14  7   7.9   4.3 | -26.8 -16.2  265  20 10   7.7   4.2
 29000 -25.8 -14.4  260  12  6   7.9   4.3 | -24.5 -12.1  265  20 10   7.7   4.2
 28000 -23.6 -10.5  250  12  6   6.3   3.5 | -22.5  -8.5  260  19 10   5.6   3.0
 27000 -21.8  -7.2  235  14  7   6.4   3.5 | -20.8  -5.4  250  15  8   5.7   3.1
 26000 -19.9  -3.8  230  15  8   6.4   3.5 | -19.1  -2.4  240  13  7   5.7   3.1
 25000 -18.0  -0.4  220  17  9   6.0   3.3 | -17.4   0.7  225  11  6   5.2   2.9
 24000 -16.3   2.7  220  16  8   5.9   3.3 | -15.9   3.4  215  12  6   5.0   2.8
 23000 -14.5   5.9  220  15  8   5.9   3.3 | -14.3   6.3  205  14  7   5.1   2.8
 22000 -12.6   9.3  220  14  7   7.4   4.1 | -12.7   9.1  200  16  8   7.1   3.9
 21000 -10.4  13.3  220  13  7   7.7   4.2 | -10.4  13.3  200  15  8   7.8   4.3
 20000  -8.1  17.4  215  12  6   7.7   4.2 |  -8.1  17.4  200  15  8   7.8   4.3
 19500  -7.0  19.4  210  12  6   7.8   4.3 |  -6.9  19.6  200  14  7   7.7   4.2
 19000  -5.7  21.7  210  11  6   8.1   4.4 |  -5.8  21.6  205  14  7   7.5   4.1
 18500  -4.5  23.9  205  11  6   8.1   4.4 |  -4.7  23.5  205  14  7   7.5   4.1
 18000  -3.2  26.2  205  12  6   8.5   4.6 |  -3.6  25.5  205  14  7   7.8   4.3
 17500  -1.9  28.6  205  12  6   8.5   4.7 |  -2.4  27.7  210  13  7   7.9   4.3
 17000  -0.6  30.9  205  13  7   8.4   4.6 |  -1.3  29.7  210  13  7   7.9   4.4
 16500   0.5  32.9  210  14  7   8.0   4.4 |  -0.1  31.8  210  13  7   8.1   4.4
 16000   1.7  35.1  210  14  7   8.0   4.4 |   1.0  33.8  205  13  7   8.2   4.5
 15500   3.5  38.3  210  15  8   8.2   4.5 |   2.7  36.9  200  13  7   9.0   5.0
 15000   4.7  40.5  210  15  8   8.2   4.5 |   3.9  39.0  200  13  7   9.2   5.1
 14500   5.8  42.4  210  15  8   8.0   4.4 |   5.2  41.4  195  13  7   9.4   5.2
 14000   6.9  44.4  205  15  8   8.0   4.4 |   6.6  43.9  195  13  7   9.4   5.2
 13500   8.1  46.6  200  14  7   8.9   4.9 |   8.0  46.4  190  13  7   9.7   5.3
 13000   9.3  48.7  200  14  7   8.9   4.9 |   9.5  49.1  190  13  7   9.8   5.4
 12500  10.5  50.9  200  14  7   9.3   5.1 |  10.9  51.6  190  13  7   9.6   5.3
 12000  11.9  53.4  195  13  7   9.4   5.1 |  12.4  54.3  190  14  7   9.5   5.2
 11500  13.2  55.8  195  13  7   9.5   5.2 |  13.8  56.8  185  15  8   9.1   5.0
 11000  14.6  58.3  195  12  6   9.7   5.3 |  15.2  59.4  185  16  8   8.5   4.7
 10500  15.8  60.4  195  12  6   4.6   2.5 |  16.5  61.7  185  17  9   4.6   2.5
 10250  16.2  61.2  195  12  6   8.3   4.6 |  16.7  62.1  185  18  9   5.7   3.1
 10000  17.1  62.8  195  12  6  13.5   7.4 |  17.5  63.5  185  18  9  11.3   6.2
  9750  18.0  64.4  195  11  6  12.2   6.7 |  18.2  64.8  180  19 10  10.4   5.7
  9500  18.9  66.0  195  11  6   9.1   5.0 |  19.0  66.2  180  19 10   8.4   4.6
  9250  19.4  66.9  195  11  6   8.2   4.5 |  19.5  67.1  180  19 10   7.6   4.2
  9000  20.2  68.4  195  11  6  11.3   6.2 |  20.2  68.4  180  19 10  10.4   5.7
  8750  21.0  69.8  195  11  6  11.3   6.2 |  20.9  69.6  180  19 10  10.6   5.8
  8500  21.8  71.2  195  11  6  10.3   5.7 |  21.7  71.1  180  19 10  10.4   5.7
  8250  22.5  72.5  195  11  6   9.9   5.4 |  22.4  72.3  180  19 10  10.5   5.7
  8000  23.3  73.9  195  11  5   9.5   5.2 |  23.2  73.8  180  19 10   9.8   5.4
  7750  24.0  75.2  195  11  5   9.4   5.1 |  23.9  75.0  180  19 10   9.2   5.0
  7500  24.7  76.5  195  10  5  10.2   5.6 |  24.6  76.3  180  19 10   9.8   5.4
  7250  25.5  77.9  200  10  5  10.6   5.8 |  25.4  77.7  180  19 10  10.0   5.5
  7000  26.3  79.3  200  10  5  10.0   5.5 |  26.1  79.0  180  18  9   9.8   5.4
  6750  27.0  80.6  200  10  5  10.0   5.5 |  26.8  80.2  180  18  9  10.0   5.5
  6500  27.8  82.0  200  10  5  10.7   5.9 |  27.6  81.7  180  18  9  10.4   5.7
  6250  28.6  83.5  200  10  5  11.0   6.1 |  28.3  82.9  180  17  9  10.9   6.0
  6000  29.4  84.9  200   9  5  10.1   5.5 |  29.1  84.4  180  16  8   9.6   5.2
  5750  30.2  86.4  200   9  5  15.0   8.3 |  29.8  85.6  180  16  8   9.9   5.4
  5500  31.8  89.2  200   9  5  25.8  14.1 |  30.7  87.3  180  13  7  14.6   8.0
________________________________________________________________________________

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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