Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261135
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0535 MDT Wednesday, August 26, 2015

This forecast is for Wednesday, August 26, 2015:

If the trigger temperature of 78.7 F/25.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 721 ft/min (3.7 m/s)
   Maximum height of thermals.................. 18464 ft MSL (11295 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10432 ft MSL (3263 ft AGL)
Thermal soaring outlook for Thursday 08/27..... Good

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:22:16 / 19:40:00 MDT
Total possible sunshine........... 13 hr 17 min 44 sec (797 min 44 sec)
Altitude of sun at 13:00:44 MDT... 61.36 degrees

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

Freezing level.................. 16529 ft MSL (9360 ft AGL)
Convective condensation level... 18131 ft MSL (10962 ft AGL)
Lifted condensation level....... 18264 ft MSL (11095 ft AGL)
Lifted index.................... -2.2
K index......................... +22.0

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  -65.9 -86.6   320   29   15   2.5   1.4      M     M       M      M    M
 45000  -61.1 -78.0   305   45   23   4.4   2.4      M     M       M      M    M
 40000  -53.3 -63.9   300   57   30   8.0   4.4      M     M       M      M    M
 38000  -48.5 -55.3   300   50   26   8.0   4.4      M     M       M      M    M
 36000  -43.7 -46.7   305   43   22   8.0   4.4      M     M       M      M    M
 34000  -38.9 -38.0   305   35   18   8.0   4.4      M     M       M      M    M
 32000  -34.1 -29.4   305   26   14   8.4   4.6      M     M       M      M    M
 30000  -30.0 -22.0   300   17    9   6.8   3.7   40.0 104.1     8.6      M    M
 29000  -28.0 -18.4   295   13    6   6.8   3.7   39.0 102.1     7.8      M    M
 28000  -26.0 -14.8   285    8    4   7.2   3.9   38.0 100.3     7.1      M    M
 27000  -23.8 -10.8   265    6    3   7.2   4.0   36.9  98.4     6.3      M    M
 26000  -21.7  -7.1   230    5    3   7.2   4.0   36.0  96.7     5.6      M    M
 25000  -19.1  -2.4   195    6    3   6.9   3.8   34.9  94.8     4.7      M    M
 24000  -17.0   1.4   195    8    4   6.9   3.8   33.8  92.8     3.8      M    M
 23000  -15.0   5.0   200    9    4   6.9   3.8   32.8  91.0     3.0      M    M
 22000  -12.9   8.8   200   10    5   7.5   4.1   31.9  89.4     2.2      M    M
 21000  -10.7  12.7   200   10    5   7.5   4.1   31.0  87.8     1.5      M    M
 20000   -8.4  16.9   200   10    5   7.5   4.1   30.3  86.5     0.9      M    M
 19500   -7.3  18.9   200   10    5   7.9   4.3   29.9  85.9     0.6      M    M
 19000   -6.1  21.0   200   11    5   8.1   4.5   29.6  85.3     0.3      M    M
 18500   -4.9  23.2   195   11    6   8.1   4.4   29.4  84.9     0.0      M    M
 18000   -3.7  25.3   195   11    6   8.8   4.8   29.2  84.5    -0.2   1072  5.4
 17500   -2.4  27.7   195   12    6   8.7   4.8   29.0  84.1    -0.4   1020  5.2
 17000   -1.2  29.8   195   12    6   8.5   4.6   28.8  83.9    -0.6    967  4.9
 16500    0.0  32.0   195   13    7   8.3   4.6   28.5  83.4    -0.9    917  4.7
 16000    1.2  34.2   200   13    7   8.3   4.6   28.3  83.0    -1.2    867  4.4
 15500    2.4  36.3   200   14    7   8.2   4.5   28.1  82.5    -1.5    817  4.1
 15000    3.6  38.5   205   14    7   8.2   4.5   27.8  82.1    -1.8    766  3.9
 14500    4.8  40.6   205   15    8   9.1   5.0   27.6  81.7    -2.0    715  3.6
 14000    6.1  43.0   205   15    8   9.1   5.0   27.5  81.5    -2.1    660  3.4
 13500    7.5  45.5   210   16    8   9.1   5.0   27.4  81.3    -2.3    605  3.1
 13000    8.8  47.8   210   15    8   9.0   4.9   27.3  81.1    -2.4    549  2.8
 12500   10.2  50.4   210   14    7   8.2   4.5   27.2  81.0    -2.5    494  2.5
 12000   11.5  52.7   210   13    7   9.5   5.2   27.0  80.6    -2.7    440  2.2
 11750   12.2  54.0   210   13    7   9.2   5.0   27.0  80.5    -2.7    412  2.1
 11500   12.9  55.2   215   13    7   9.2   5.0   26.9  80.5    -2.7    384  2.0
 11250   13.5  56.3   215   13    6   9.1   5.0   26.9  80.4    -2.8    356  1.8
 11000   14.2  57.6   215   12    6   9.1   5.0   26.8  80.3    -2.8    328  1.7
 10750   14.9  58.8   220   12    6   9.2   5.0   26.8  80.2    -2.9    300  1.5
 10500   15.6  60.1   220   12    6   9.3   5.1   26.7  80.1    -3.0    273  1.4
 10250   16.3  61.3   220   12    6   9.6   5.3   26.7  80.1    -3.0    244  1.2
 10000   17.0  62.6   220   12    6   9.2   5.1   26.7  80.1    -3.0    216  1.1
  9750   18.2  64.8   225   12    6   7.5   4.1   26.4  79.6    -3.3    166  0.8
  9500   18.7  65.7   220   12    6   8.3   4.6   26.3  79.3    -3.5    141  0.7
  9250   19.4  66.9   220   12    6   8.3   4.6   26.2  79.1    -3.6    115  0.6
  9000   20.0  68.0   220   12    6   8.4   4.6   26.1  78.9    -3.7     90  0.5
  8750   20.5  68.9   220   11    6   5.4   2.9   25.9  78.6    -3.9     66  0.3
  8500   20.7  69.3   220   11    6   2.3   1.2   25.4  77.7    -4.5     53  0.3
  8250   20.8  69.4   220   11    5   2.4   1.3   24.8  76.7    -5.1     41  0.2
  8000   21.0  69.8   220   10    5   2.4   1.3   24.3  75.7    -5.7     29  0.1
  7750   20.7  69.3   220   10    5 -14.6  -8.0   23.3  74.0    -6.8     32  0.2
  7500   18.3  64.9   235    8    4 -42.2 -23.2   20.4  68.7    -9.8     94  0.5
  7250   16.0  60.8   255    6    3   6.9   3.8   17.4  63.4   -12.9    157  0.8
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/26/2015 at 0900 MDT          |       08/26/2015 at 1200 MDT
                                           |
K index... +18.0  LI... +272.2             | K index... +12.6  LI... +272.4
CAPE... +141.3  CIN... -65.4               | CAPE... +140.8  CIN... -29.6
                                           |
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 -65.5 -85.9  320  29 15   2.6   1.4 | -65.7 -86.3  320  29 15   3.1   1.7
 45000 -61.0 -77.8  310  45 23   3.9   2.1 | -60.4 -76.7  310  45 23   3.8   2.1
 40000 -53.9 -65.0  290  52 27   8.0   4.4 | -53.6 -64.5  290  53 27   8.0   4.4
 38000 -49.1 -56.4  295  43 22   8.0   4.4 | -48.8 -55.8  290  43 22   8.0   4.4
 36000 -44.2 -47.6  305  35 18   8.3   4.5 | -43.9 -47.0  290  33 17   8.4   4.6
 34000 -39.1 -38.4  305  29 15   8.5   4.7 | -38.8 -37.8  295  26 13   8.6   4.7
 32000 -34.0 -29.2  305  24 12   8.9   4.9 | -33.6 -28.5  300  19 10   9.0   4.9
 30000 -29.8 -21.6  305  17  9   7.1   3.9 | -29.0 -20.2  290  13  7   7.7   4.2
 29000 -27.6 -17.7  300  13  7   7.1   3.9 | -26.7 -16.1  280  10  5   7.7   4.2
 28000 -25.5 -13.9  290  10  5   6.9   3.8 | -24.0 -11.2  265   8  4   6.3   3.4
 27000 -23.5 -10.3  275   7  4   6.9   3.8 | -22.1  -7.8  250   7  4   6.3   3.5
 26000 -20.9  -5.6  240   6  3   7.0   3.8 | -20.3  -4.5  230   7  4   6.3   3.5
 25000 -18.9  -2.0  215   7  4   7.1   3.9 | -18.4  -1.1  215   7  4   6.7   3.7
 24000 -16.7   1.9  215   8  4   7.1   3.9 | -16.3   2.7  210   9  4   6.8   3.7
 23000 -14.6   5.7  215   9  4   7.1   3.9 | -14.3   6.3  205  10  5   6.7   3.7
 22000 -12.5   9.5  215   9  5   7.2   3.9 | -12.2  10.0  200  11  6   7.4   4.1
 21000 -10.3  13.5  205   9  5   7.2   3.9 |  -9.9  14.2  190  11  5   7.4   4.1
 20000  -8.1  17.4  190   9  5   7.2   3.9 |  -7.7  18.1  180  11  6   7.4   4.1
 19500  -7.1  19.2  190  10  5   7.2   3.9 |  -6.6  20.1  175  11  6   7.4   4.0
 19000  -6.0  21.2  190  10  5   7.1   3.9 |  -5.5  22.1  175  11  6   7.3   4.0
 18500  -5.0  23.0  190  11  5   7.1   3.9 |  -4.4  24.1  175  12  6   7.3   4.0
 18000  -3.9  25.0  190  11  6   8.2   4.5 |  -3.3  26.1  180  12  6   7.6   4.1
 17500  -2.7  27.1  190  13  6   8.1   4.4 |  -2.2  28.0  185  11  6   7.6   4.2
 17000  -1.5  29.3  195  14  7   8.2   4.5 |  -1.1  30.0  195  11  6   7.7   4.2
 16500  -0.3  31.5  200  14  7   8.3   4.6 |  -0.0  32.0  200  12  6   7.8   4.3
 16000   0.9  33.6  200  15  8   8.4   4.6 |   1.1  34.0  205  14  7   7.8   4.3
 15500   2.1  35.8  205  16  8   8.7   4.8 |   2.2  36.0  210  15  8   8.1   4.4
 15000   3.3  37.9  205  17  9   8.8   4.8 |   3.4  38.1  210  17  9   8.0   4.4
 14500   4.6  40.3  210  18  9   8.7   4.8 |   4.6  40.3  210  18 10   8.8   4.8
 14000   5.9  42.6  210  18  9   8.7   4.8 |   5.9  42.6  210  20 10   8.8   4.8
 13500   7.1  44.8  210  19 10   8.8   4.8 |   7.2  45.0  210  20 10   8.9   4.9
 13000   8.4  47.1  210  19 10   8.8   4.8 |   8.4  47.1  215  20 10   8.8   4.8
 12500   9.7  49.5  210  20 10   7.7   4.2 |   9.7  49.5  215  20 10   6.8   3.7
 12000  11.1  52.0  210  19 10  10.6   5.8 |  10.9  51.6  215  20 10  10.7   5.9
 11750  11.8  53.2  210  19 10  10.4   5.7 |  11.6  52.9  210  19 10  10.1   5.6
 11500  12.6  54.7  210  19 10   9.7   5.3 |  12.4  54.3  210  19 10   9.6   5.3
 11250  13.2  55.8  210  18  9   8.7   4.8 |  13.0  55.4  210  18  9   8.7   4.8
 11000  13.9  57.0  210  18  9   9.0   5.0 |  13.6  56.5  210  17  9   9.4   5.2
 10750  14.6  58.3  215  17  9   9.2   5.0 |  14.3  57.7  210  17  9   9.6   5.3
 10500  15.2  59.4  215  17  9   9.2   5.0 |  15.0  59.0  210  17  9   9.9   5.4
 10250  15.9  60.6  215  16  8   9.4   5.2 |  16.5  61.7  205  16  8  10.3   5.6
 10000  17.2  63.0  220  16  8   7.5   4.1 |  17.2  63.0  205  16  8   8.9   4.9
  9750  17.7  63.9  220  16  8   7.6   4.2 |  17.9  64.2  205  16  8   9.3   5.1
  9500  18.3  64.9  220  16  8   8.6   4.7 |  18.6  65.5  205  16  8  10.4   5.7
  9250  18.9  66.0  220  16  8   8.6   4.7 |  19.4  66.9  205  16  8  10.8   5.9
  9000  19.6  67.3  225  16  8   8.4   4.6 |  20.2  68.4  205  16  8   9.1   5.0
  8750  20.1  68.2  225  16  8   6.4   3.5 |  20.8  69.4  200  16  8   9.1   5.0
  8500  20.5  68.9  225  15  8   5.3   2.9 |  21.6  70.9  200  16  8  11.1   6.1
  8250  20.8  69.4  225  14  7   4.9   2.7 |  22.4  72.3  200  16  8  10.6   5.8
  8000  21.2  70.2  225  13  7   7.4   4.1 |  23.2  73.8  200  15  8  11.0   6.1
  7750  21.8  71.2  225  13  7   8.8   4.8 |  24.1  75.4  200  15  8  16.2   8.9
  7500  22.1  71.8  220  10  5   3.2   1.8 |  25.6  78.1  200  14  7  23.9  13.1
  7250  22.4  72.3  215   7  4  16.1   8.8 |  27.1  80.8  195  13  7  10.7   5.9
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/26/2015 at 1500 MDT          |       08/26/2015 at 1800 MDT
                                           |
K index... +8.6  LI... +273.1              | K index... +21.6  LI... +272.2
CAPE... +52.7  CIN... -46.8                | CAPE... +58.2  CIN... -62.5
                                           |
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 -65.9 -86.6  310  32 16   3.6   2.0 | -66.1 -87.0  315  33 17   3.5   1.9
 45000 -60.3 -76.5  305  46 24   3.6   2.0 | -60.6 -77.1  310  44 23   3.6   2.0
 40000 -53.5 -64.3  285  52 27   8.7   4.8 | -53.7 -64.7  300  40 21   9.2   5.1
 38000 -48.3 -54.9  280  45 23   8.7   4.8 | -48.2 -54.8  290  35 18   9.2   5.1
 36000 -43.1 -45.6  275  39 20   8.9   4.9 | -42.7 -44.9  285  31 16   9.0   4.9
 34000 -37.7 -35.9  275  31 16   9.0   4.9 | -37.4 -35.3  285  29 15   8.8   4.8
 32000 -32.3 -26.1  280  23 12   9.6   5.3 | -32.1 -25.8  280  26 13   9.5   5.2
 30000 -27.5 -17.5  270  14  7   7.0   3.9 | -26.8 -16.2  275  22 11   7.9   4.3
 29000 -25.4 -13.7  255  10  5   7.0   3.9 | -24.5 -12.1  270  21 11   7.9   4.3
 28000 -23.5 -10.3  240   8  4   5.6   3.1 | -22.3  -8.1  265  19 10   6.2   3.4
 27000 -21.8  -7.2  220   9  5   5.6   3.1 | -20.5  -4.9  255  18  9   6.3   3.5
 26000 -20.1  -4.2  205  10  5   5.6   3.1 | -18.6  -1.5  245  18  9   6.4   3.5
 25000 -18.4  -1.1  195  12  6   6.4   3.5 | -16.8   1.8  235  19 10   5.0   2.8
 24000 -16.3   2.7  190  14  7   6.7   3.7 | -15.5   4.1  220  18  9   4.5   2.4
 23000 -14.3   6.3  190  16  8   6.7   3.7 | -14.1   6.6  210  19 10   4.4   2.4
 22000 -12.2  10.0  185  18  9   7.5   4.1 | -12.7   9.1  200  20 10   6.5   3.6
 21000  -9.9  14.2  190  17  9   7.6   4.2 | -10.5  13.1  195  18  9   7.2   3.9
 20000  -7.7  18.1  190  16  8   7.6   4.2 |  -8.4  16.9  195  16  8   7.2   4.0
 19500  -6.5  20.3  195  16  8   7.7   4.2 |  -7.3  18.9  190  15  8   7.7   4.2
 19000  -5.4  22.3  195  15  8   7.7   4.2 |  -6.0  21.2  195  15  7   9.3   5.1
 18500  -4.3  24.3  200  15  8   7.7   4.2 |  -4.6  23.7  200  15  8   9.3   5.1
 18000  -3.1  26.4  205  14  7   8.0   4.4 |  -3.3  26.1  205  15  8   7.9   4.3
 17500  -1.9  28.6  205  15  8   8.1   4.4 |  -2.2  28.0  210  16  8   7.7   4.2
 17000  -0.7  30.7  205  15  8   8.1   4.4 |  -1.1  30.0  215  16  8   7.7   4.2
 16500   0.4  32.7  210  15  8   8.0   4.4 |  -0.1  31.8  215  17  9   7.8   4.3
 16000   1.6  34.9  210  16  8   8.0   4.4 |   1.0  33.8  210  17  9   7.8   4.3
 15500   2.8  37.0  210  16  8   8.3   4.6 |   2.2  36.0  210  17  9   8.3   4.5
 15000   4.6  40.3  210  16  8   8.3   4.6 |   3.9  39.0  205  18  9   8.3   4.6
 14500   5.8  42.4  210  17  9   8.3   4.5 |   5.2  41.4  200  18  9   8.8   4.8
 14000   7.0  44.6  210  17  9   8.3   4.5 |   6.5  43.7  195  19 10   8.8   4.8
 13500   8.2  46.8  205  18  9   8.8   4.8 |   7.7  45.9  195  20 10   8.6   4.7
 13000   9.5  49.1  205  18  9   9.0   4.9 |   9.0  48.2  190  21 11   8.6   4.7
 12500  10.7  51.3  200  19 10   8.3   4.5 |  10.3  50.5  190  21 11   8.5   4.7
 12000  12.0  53.6  200  19 10   9.2   5.0 |  11.5  52.7  190  22 11   8.7   4.8
 11750  12.7  54.9  195  19 10   9.2   5.0 |  12.2  54.0  190  22 11   8.7   4.8
 11500  13.3  55.9  195  20 10   8.6   4.7 |  12.8  55.0  185  23 12   9.2   5.1
 11250  13.9  57.0  195  20 10   8.9   4.9 |  13.5  56.3  185  23 12   8.9   4.9
 11000  14.6  58.3  190  20 10   9.5   5.2 |  14.2  57.6  185  23 12   8.2   4.5
 10750  15.3  59.5  190  20 10   9.4   5.1 |  14.8  58.6  185  23 12   8.4   4.6
 10500  16.0  60.8  190  20 10   9.6   5.3 |  15.4  59.7  185  23 12   9.1   5.0
 10250  16.6  61.9  190  20 10   9.8   5.4 |  16.1  61.0  185  23 12   9.8   5.4
 10000  17.3  63.1  185  20 10   9.6   5.3 |  16.8  62.2  185  23 12   9.0   5.0
  9750  18.0  64.4  185  20 10   9.6   5.2 |  17.5  63.5  185  23 12   8.6   4.7
  9500  18.7  65.7  185  20 10  10.1   5.5 |  18.1  64.6  185  23 12   8.9   4.9
  9250  19.5  67.1  185  20 10  10.5   5.8 |  18.8  65.8  185  23 12   9.0   4.9
  9000  20.2  68.4  185  20 10  10.0   5.5 |  19.5  67.1  185  23 12   9.2   5.0
  8750  21.0  69.8  185  20 10   9.4   5.1 |  20.2  68.4  185  22 11   9.8   5.4
  8500  21.7  71.1  185  20 10  10.2   5.6 |  20.9  69.6  185  22 11   9.5   5.2
  8250  22.5  72.5  185  20 10  10.9   6.0 |  21.6  70.9  185  21 11   9.2   5.0
  8000  23.3  73.9  180  20 10  10.4   5.7 |  22.3  72.1  185  20 10   9.2   5.1
  7750  24.1  75.4  180  19 10  11.8   6.4 |  22.9  73.2  185  19 10   9.4   5.2
  7500  24.9  76.8  180  19 10  12.0   6.6 |  23.5  74.3  185  19 10   6.8   3.7
  7250  25.7  78.3  180  18  9  10.6   5.8 |  23.9  75.0  185  17  9   4.2   2.3
  7000  26.5  79.7  180  17  9  11.8   6.5 |  24.2  75.6  185  15  8   6.2   3.4
  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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