Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 151058
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0458 MDT Friday, August 15, 2014

This forecast is for Friday, August 15, 2014:

If the trigger temperature of 71.7 F/22.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 846 ft/min (4.3 m/s)
   Maximum height of thermals.................. 16113 ft MSL (9355 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1000 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................. 12269 ft MSL (5511 ft AGL)
Thermal soaring outlook for Saturday 08/16..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 17313 ft MSL (10555 ft AGL)
Wave soaring outlook for Saturday 08/16........ Poor

Remarks...

Sunrise/Sunset.................... 06:12:31 / 19:54:50 MDT
Total possible sunshine........... 13 hr 42 min 20 sec (822 min 20 sec)
Altitude of sun at 13:03:21 MDT... 64.93 degrees

Upper air data from numerical model forecast valid on 08/15/2014 at 0600 MDT

Freezing level.................. 15746 ft MSL (8988 ft AGL)
Convective condensation level... 14698 ft MSL (7940 ft AGL)
Lifted condensation level....... 14907 ft MSL (8149 ft AGL)
Lifted index.................... -1.8
K index......................... +17.3

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  -65.4 -85.7   250   23   12   1.8   1.0      M     M       M      M    M
 45000  -61.1 -78.0   255   36   19   5.3   2.9      M     M       M      M    M
 40000  -52.1 -61.8   260   48   25   8.0   4.4      M     M       M      M    M
 38000  -47.4 -53.3   255   46   24   8.0   4.4      M     M       M      M    M
 36000  -42.6 -44.7   250   44   23   8.0   4.4      M     M       M      M    M
 34000  -37.9 -36.2   250   39   20   7.9   4.3      M     M       M      M    M
 32000  -33.1 -27.6   255   33   17   7.8   4.3      M     M       M      M    M
 30000  -28.7 -19.7   260   28   14   7.3   4.0   41.9 107.4    12.2      M    M
 29000  -26.5 -15.7   255   25   13   7.3   4.0   41.0 105.8    11.7      M    M
 28000  -24.3 -11.7   255   23   12   7.3   4.0   40.2 104.4    11.2      M    M
 27000  -21.6  -6.9   265   20   10   7.3   4.0   38.9 102.0    10.3      M    M
 26000  -19.4  -2.9   270   18    9   7.3   4.0   38.0 100.5     9.7      M    M
 25000  -17.2   1.0   280   17    9   7.2   3.9   37.3  99.1     9.2      M    M
 24000  -15.2   4.6   285   15    8   7.0   3.8   36.2  97.1     8.3      M    M
 23000  -13.1   8.4   290   14    7   7.0   3.8   35.2  95.3     7.5      M    M
 22000  -11.1  12.0   295   12    6   6.1   3.4   34.3  93.8     6.8      M    M
 21000   -9.6  14.7   300   11    6   5.2   2.9   32.6  90.7     5.4      M    M
 20000   -8.0  17.6   305   11    6   5.2   2.9   31.1  87.9     4.1      M    M
 19500   -7.3  18.9   305   11    6   5.1   2.8   30.3  86.6     3.5      M    M
 19000   -6.4  20.5   305   11    6   6.8   3.8   29.7  85.5     2.9      M    M
 18500   -5.4  22.3   305   11    6   6.7   3.7   29.2  84.6     2.5      M    M
 18000   -4.4  24.1   305   11    6   6.7   3.7   28.7  83.7     2.0      M    M
 17500   -3.5  25.7   305   12    6   6.7   3.7   28.2  82.7     1.5      M    M
 17000   -2.5  27.5   310   13    6   6.8   3.7   27.7  81.8     1.0      M    M
 16500   -1.6  29.1   310   13    7   6.3   3.5   27.2  80.9     0.5      M    M
 16000   -0.6  30.9   315   13    7   6.4   3.5   26.6  79.9    -0.0    844  4.3
 15500    0.3  32.5   315   13    7   6.9   3.8   26.1  78.9    -0.5    801  4.1
 15000    1.3  34.3   320   13    7   7.1   3.9   25.6  78.1    -1.0    755  3.8
 14500    2.4  36.3   320   13    7   7.4   4.0   25.2  77.4    -1.4    709  3.6
 14000    3.5  38.3   320   13    7   7.9   4.3   24.9  76.8    -1.8    661  3.4
 13500    5.2  41.4   325   13    7   8.1   4.4   24.4  76.0    -2.3    589  3.0
 13000    6.3  43.3   325   14    7   8.2   4.5   24.2  75.5    -2.6    539  2.7
 12500    7.5  45.5   325   14    7   7.8   4.3   23.9  75.1    -2.9    490  2.5
 12000    8.6  47.5   330   15    8   8.7   4.8   23.7  74.6    -3.2    441  2.2
 11750    9.2  48.6   330   16    8   8.4   4.6   23.6  74.5    -3.4    416  2.1
 11500    9.8  49.6   330   16    8   8.9   4.9   23.5  74.3    -3.5    390  2.0
 11250   10.4  50.7   330   17    9   8.6   4.7   23.4  74.2    -3.6    364  1.8
 11000   11.0  51.8   330   17    9   7.9   4.3   23.3  74.0    -3.8    340  1.7
 10750   11.6  52.9   330   17    9   8.0   4.4   23.2  73.7    -4.0    316  1.6
 10500   12.1  53.8   330   17    9   8.0   4.4   23.0  73.5    -4.1    292  1.5
 10250   12.7  54.9   335   17    9   8.3   4.5   22.9  73.2    -4.3    267  1.4
 10000   13.3  55.9   335   17    9   7.7   4.2   22.8  73.0    -4.5    243  1.2
  9750   13.8  56.8   335   17    9   7.2   3.9   22.6  72.7    -4.7    220  1.1
  9500   14.3  57.7   335   17    9   7.5   4.1   22.4  72.4    -4.9    197  1.0
  9250   14.8  58.6   335   16    8   7.8   4.3   22.3  72.1    -5.1    174  0.9
  9000   15.4  59.7   335   15    8   7.7   4.2   22.1  71.8    -5.3    150  0.8
  8750   15.9  60.6   335   15    7   7.8   4.3   22.0  71.5    -5.5    126  0.6
  8500   16.5  61.7   335   14    7   5.9   3.3   21.8  71.2    -5.7    103  0.5
  8250   16.8  62.2   330   13    7   4.0   2.2   21.4  70.5    -6.2     86  0.4
  8000   17.1  62.8   330   13    7   5.4   3.0   21.0  69.8    -6.6     69  0.4
  7750   17.4  63.3   325   13    6   1.7   0.9   20.6  69.1    -7.0     52  0.3
  7500   17.1  62.8   320   12    6 -11.4  -6.2   19.6  67.4    -8.0     55  0.3
  7250   15.8  60.4   315   11    5 -18.6 -10.2   18.0  64.5    -9.6     86  0.4
  7000   14.5  58.1   310    9    5 -13.4  -7.4   16.5  61.6   -11.2    116  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/15/2014 at 0900 MDT          |       08/15/2014 at 1200 MDT
                                           |
K index... +13.4  LI... -1.9               | K index... +21.5  LI... -1.7
CAPE... +156.4  CIN... -40.4               | CAPE... +134.8  CIN... -5.0
                                           |
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  250  22 11   1.9   1.1 | -64.7 -84.5  255  24 12   1.8   1.0
 45000 -60.7 -77.3  250  33 17   5.1   2.8 | -60.6 -77.1  255  34 17   4.9   2.7
 40000 -52.2 -62.0  255  40 20   7.4   4.0 | -52.4 -62.3  250  34 17   7.2   4.0
 38000 -47.8 -54.0  255  44 22   7.4   4.0 | -48.1 -54.6  250  36 18   7.2   3.9
 36000 -43.4 -46.1  250  48 24   7.7   4.2 | -43.8 -46.8  255  38 20   7.4   4.0
 34000 -38.4 -37.1  255  43 22   8.4   4.6 | -39.0 -38.2  255  33 17   8.1   4.4
 32000 -33.4 -28.1  260  38 20   8.4   4.6 | -34.2 -29.6  260  28 14   8.0   4.4
 30000 -28.8 -19.8  260  29 15   7.4   4.1 | -29.6 -21.3  265  21 11   7.6   4.2
 29000 -26.6 -15.9  265  23 12   7.4   4.1 | -26.8 -16.2  275  17  9   7.6   4.2
 28000 -24.4 -11.9  270  18 10   7.3   4.0 | -24.5 -12.1  280  14  7   7.7   4.2
 27000 -21.7  -7.1  275  17  9   7.2   4.0 | -22.3  -8.1  285  14  7   7.7   4.2
 26000 -19.5  -3.1  280  17  9   7.2   4.0 | -20.0  -4.0  295  13  7   7.7   4.2
 25000 -17.4   0.7  290  16  8   7.0   3.8 | -17.7   0.1  300  13  7   7.2   4.0
 24000 -15.4   4.3  290  15  8   6.8   3.7 | -15.7   3.7  305  14  7   6.8   3.7
 23000 -13.3   8.1  290  14  7   6.8   3.7 | -13.7   7.3  305  15  8   6.8   3.7
 22000 -11.3  11.7  290  14  7   5.9   3.3 | -11.6  11.1  310  16  8   6.0   3.3
 21000  -9.8  14.4  295  13  7   5.2   2.8 | -10.1  13.8  315  17  9   5.4   3.0
 20000  -8.3  17.1  305  12  6   5.2   2.8 |  -8.5  16.7  315  18  9   5.5   3.0
 19500  -7.6  18.3  305  12  6   5.2   2.8 |  -7.8  18.0  320  18  9   5.6   3.1
 19000  -6.8  19.8  310  12  6   6.2   3.4 |  -6.9  19.6  315  17  9   6.7   3.7
 18500  -5.9  21.4  310  11  6   6.1   3.3 |  -5.9  21.4  315  16  8   6.6   3.6
 18000  -4.9  23.2  315  11  6   6.3   3.5 |  -4.9  23.2  310  14  7   6.6   3.6
 17500  -4.0  24.8  315  10  5   6.6   3.6 |  -3.9  25.0  310  13  7   6.7   3.7
 17000  -3.0  26.6  320  10  5   6.6   3.6 |  -2.9  26.8  305  13  7   6.7   3.7
 16500  -2.1  28.2  330  10  5   6.7   3.7 |  -2.0  28.4  300  12  6   6.1   3.4
 16000  -1.1  30.0  335  10  5   6.7   3.7 |  -1.2  29.8  305  11  6   6.2   3.4
 15500  -0.1  31.8  340  10  5   7.5   4.1 |  -0.3  31.5  305  11  5   7.0   3.8
 15000   1.0  33.8  350  10  5   7.8   4.3 |   0.7  33.3  310  10  5   7.1   3.9
 14500   2.1  35.8  355  10  5   8.0   4.4 |   1.8  35.2  320   9  5   7.2   4.0
 14000   3.9  39.0  360  11  6   8.3   4.5 |   3.3  37.9  330  10  5   7.3   4.0
 13500   5.1  41.2  005  12  6   8.4   4.6 |   4.4  39.9  340  11  5   7.9   4.3
 13000   6.3  43.3  005  13  7   8.5   4.7 |   5.5  41.9  350  12  6   8.1   4.4
 12500   7.5  45.5  005  14  7   8.2   4.5 |   6.6  43.9  355  13  6   9.1   5.0
 12000   8.8  47.8  005  14  7   8.7   4.8 |   8.0  46.4  355  12  6   9.7   5.3
 11750   9.4  48.9  005  14  7   8.7   4.8 |   8.7  47.7  360  12  6   9.7   5.3
 11500  10.0  50.0  005  15  8   8.7   4.8 |   9.4  48.9  360  12  6  10.2   5.6
 11250  10.7  51.3  005  15  8   7.8   4.3 |  10.2  50.4  360  12  6  10.1   5.5
 11000  11.2  52.2  360  14  7   7.1   3.9 |  10.9  51.6  360  11  6   9.5   5.2
 10750  11.7  53.1  360  14  7   7.1   3.9 |  11.6  52.9  360  11  6   9.5   5.2
 10500  12.2  54.0  360  14  7   7.3   4.0 |  12.3  54.1  360  11  6  10.0   5.5
 10250  12.7  54.9  355  14  7   7.6   4.2 |  13.1  55.6  360  11  5  10.5   5.8
 10000  13.2  55.8  350  14  7   7.1   3.9 |  13.8  56.8  360  11  5   9.8   5.4
  9750  13.7  56.7  350  15  8   6.5   3.5 |  14.5  58.1  360  10  5   9.2   5.1
  9500  14.1  57.4  345  16  8   7.3   4.0 |  15.2  59.4  360  10  5   9.8   5.4
  9250  14.7  58.5  345  16  8   7.9   4.4 |  16.0  60.8  360  10  5  10.1   5.5
  9000  15.2  59.4  340  16  8   8.0   4.4 |  16.7  62.1  360  10  5  10.1   5.5
  8750  15.8  60.4  340  17  9   8.6   4.7 |  17.5  63.5  360  10  5  10.2   5.6
  8500  16.4  61.5  340  17  9   8.6   4.7 |  18.2  64.8  360  10  5  10.3   5.7
  8250  16.9  62.4  335  16  8   8.5   4.6 |  19.0  66.2  360  10  5  10.5   5.8
  8000  17.5  63.5  335  15  7   8.1   4.5 |  19.8  67.6  360   9  5   9.9   5.4
  7750  18.0  64.4  330  13  7   9.9   5.4 |  20.5  68.9  360   9  5  12.3   6.8
  7500  18.7  65.7  325  12  6   8.9   4.9 |  21.5  70.7  360   9  5  13.2   7.3
  7250  19.1  66.4  320  11  5   5.8   3.2 |  22.4  72.3  360   9  5  11.0   6.0
  7000  19.6  67.3  320   9  5   8.3   4.6 |  23.2  73.8  360   9  4  12.9   7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/15/2014 at 1500 MDT          |       08/15/2014 at 1800 MDT
                                           |
K index... +23.6  LI... -1.4               | K index... +29.3  LI... -1.5
CAPE... +221.8  CIN... -6.3                | CAPE... +142.8  CIN... -12.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.9 -84.8  255  24 12   2.0   1.1 | -64.9 -84.8  260  24 13   2.1   1.2
 45000 -60.6 -77.1  255  32 16   4.7   2.6 | -60.8 -77.4  265  30 15   4.3   2.4
 40000 -52.6 -62.7  260  24 12   7.5   4.1 | -53.1 -63.6  285  20 10   8.0   4.4
 38000 -48.1 -54.6  270  20 10   7.4   4.1 | -48.3 -54.9  285  19 10   8.0   4.4
 36000 -43.7 -46.7  275  17  9   7.5   4.1 | -43.6 -46.5  290  18  9   8.0   4.4
 34000 -39.1 -38.4  280  16  8   7.7   4.2 | -38.8 -37.8  290  18  9   8.0   4.4
 32000 -34.5 -30.1  285  15  8   7.5   4.1 | -34.0 -29.2  295  18  9   7.8   4.3
 30000 -29.7 -21.5  285  14  7   8.1   4.5 | -29.3 -20.7  295  18  9   7.9   4.3
 29000 -26.6 -15.9  285  13  6   8.1   4.5 | -27.0 -16.6  295  18  9   7.9   4.4
 28000 -24.3 -11.7  285  12  6   7.5   4.1 | -24.1 -11.4  295  17  9   7.3   4.0
 27000 -22.0  -7.6  285  11  6   7.5   4.1 | -21.9  -7.4  300  17  9   7.4   4.0
 26000 -19.8  -3.6  285  11  6   7.6   4.1 | -19.7  -3.5  300  17  9   7.4   4.0
 25000 -17.5   0.5  290  11  5   7.2   3.9 | -17.5   0.5  300  17  9   7.1   3.9
 24000 -15.5   4.1  300  12  6   6.9   3.8 | -15.5   4.1  305  17  9   6.9   3.8
 23000 -13.5   7.7  310  13  7   6.9   3.8 | -13.5   7.7  310  18  9   6.9   3.8
 22000 -11.5  11.3  320  15  8   6.5   3.5 | -11.5  11.3  310  19 10   6.3   3.5
 21000  -9.6  14.7  320  17  9   6.2   3.4 |  -9.8  14.4  315  21 11   5.9   3.3
 20000  -7.8  18.0  315  18  9   6.2   3.4 |  -8.1  17.4  315  22 11   6.0   3.3
 19500  -6.9  19.6  315  19 10   6.2   3.4 |  -7.2  19.0  315  23 12   6.0   3.3
 19000  -6.0  21.2  315  20 10   6.5   3.6 |  -6.3  20.7  315  23 12   7.2   3.9
 18500  -5.0  23.0  315  21 11   6.5   3.6 |  -5.3  22.5  315  21 11   7.1   3.9
 18000  -4.1  24.6  315  21 11   6.6   3.6 |  -4.3  24.3  315  20 10   7.0   3.8
 17500  -3.1  26.4  315  22 11   6.7   3.7 |  -3.3  26.1  315  19 10   6.8   3.8
 17000  -2.2  28.0  315  22 11   6.7   3.7 |  -2.3  27.9  315  17  9   6.9   3.8
 16500  -1.2  29.8  315  21 11   7.1   3.9 |  -1.4  29.5  315  15  8   7.1   3.9
 16000  -0.2  31.6  315  20 10   7.1   3.9 |  -0.4  31.3  315  12  6   7.1   3.9
 15500   0.8  33.4  315  19 10   7.1   3.9 |   0.6  33.1  315  10  5   7.4   4.0
 15000   1.8  35.2  315  17  9   7.1   3.9 |   1.7  35.1  325   8  4   7.4   4.1
 14500   3.3  37.9  320  13  7   7.4   4.0 |   2.8  37.0  340   7  4   7.9   4.3
 14000   4.3  39.7  330  10  5   7.3   4.0 |   4.7  40.5  005   6  3   8.5   4.6
 13500   5.4  41.7  340   8  4   9.1   5.0 |   5.9  42.6  020   6  3   9.1   5.0
 13000   6.7  44.1  345   8  4   9.4   5.2 |   7.3  45.1  025   5  3   9.2   5.1
 12500   8.1  46.6  355   7  3   9.8   5.4 |   8.7  47.7  025   5  3   9.8   5.4
 12000   9.6  49.3  355   7  3   9.9   5.4 |  10.1  50.2  030   5  2   9.6   5.2
 11750  10.3  50.5  355   7  3   9.7   5.3 |  10.8  51.4  030   5  2   9.0   4.9
 11500  11.0  51.8  355   7  3  10.6   5.8 |  11.5  52.7  035   5  2  11.1   6.1
 11250  11.9  53.4  355   6  3  10.3   5.6 |  12.4  54.3  035   4  2  10.6   5.8
 11000  12.6  54.7  355   6  3   9.3   5.1 |  13.0  55.4  035   4  2   8.2   4.5
 10750  13.3  55.9  355   6  3   9.3   5.1 |  13.7  56.7  035   4  2   8.7   4.8
 10500  14.0  57.2  355   6  3  10.1   5.5 |  14.4  57.9  040   4  2   9.3   5.1
 10250  14.8  58.6  360   6  3  11.0   6.0 |  15.1  59.2  040   4  2  10.3   5.6
 10000  15.5  59.9  360   6  3   9.7   5.3 |  15.8  60.4  040   4  2   9.8   5.4
  9750  16.2  61.2  360   6  3   8.8   4.8 |  16.5  61.7  040   4  2   9.6   5.3
  9500  16.9  62.4  360   6  3   9.5   5.2 |  17.3  63.1  045   4  2   9.5   5.2
  9250  17.6  63.7  360   6  3  10.0   5.5 |  17.9  64.2  045   4  2   9.0   5.0
  9000  18.4  65.1  360   6  3   9.9   5.4 |  18.6  65.5  045   3  2   9.4   5.2
  8750  19.1  66.4  360   6  3  10.1   5.6 |  19.4  66.9  045   3  2  10.7   5.9
  8500  19.9  67.8  005   6  3  10.3   5.7 |  20.2  68.4  045   3  2  10.5   5.7
  8250  20.7  69.3  360   6  3  10.6   5.8 |  20.9  69.6  045   3  2   9.7   5.3
  8000  21.4  70.5  360   6  3  10.0   5.5 |  21.6  70.9  050   3  2   9.9   5.4
  7750  22.2  72.0  360   6  3  12.2   6.7 |  22.4  72.3  050   3  2  10.0   5.5
  7500  23.2  73.8  005   6  3  12.8   7.0 |  23.1  73.6  045   3  1   8.6   4.7
  7250  24.0  75.2  005   5  3  10.7   5.9 |  23.6  74.5  045   3  1   7.1   3.9
  7000  24.8  76.6  005   5  3  12.5   6.9 |  24.1  75.4  045   3  1   8.3   4.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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