Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 161338
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0738 MDT Tuesday, September 16, 2014

This forecast is for Tuesday, September 16, 2014:

If the trigger temperature of 80.8 F/27.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1225 ft/min (6.2 m/s)
   Maximum height of thermals.................. 17785 ft MSL (12500 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1400 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................. 7281 ft MSL (1995 ft AGL)
Thermal soaring outlook for Wednesday 09/17.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... 6
Height of stable layer (12-18K ft MSL)......... 16000 ft MSL (10715 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 19096 ft MSL (13811 ft AGL)
Wave soaring outlook for Wednesday 09/17....... Poor

Remarks...

Sunrise/Sunset.................... 06:41:29 / 19:07:55 MDT
Total possible sunshine........... 12 hr 26 min 26 sec (746 min 26 sec)
Altitude of sun at 12:54:13 MDT... 52.69 degrees

Upper air data from rawinsonde observation taken on 09/16/2014 at 0600 MDT

Freezing level.................. 14919 ft MSL (9634 ft AGL)
Convective condensation level... 16800 ft MSL (11515 ft AGL)
Lifted condensation level....... 16941 ft MSL (11655 ft AGL)
Lifted index.................... +0.4
K index......................... +15.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -66.1 -87.0   305   45   23  -4.0  -2.2   83.7 182.7    31.5      M    M
 45000  -62.3 -80.1   285   72   37   2.6   1.4   65.5 149.8    22.4      M    M
 40000  -53.8 -64.8   290   61   32   8.1   4.4   55.8 132.4    17.6      M    M
 38000  -49.0 -56.2   295   64   33   8.4   4.6   54.3 129.8    17.0      M    M
 36000  -46.3 -51.3   295   51   26   1.8   1.0   49.6 121.3    14.2      M    M
 34000  -43.4 -46.1   295   39   20   7.0   3.8   44.6 112.2    10.9      M    M
 32000  -38.7 -37.7   300   34   17   9.1   5.0   43.0 109.4    10.1      M    M
 30000  -33.0 -27.4   295   33   17   8.1   4.4   42.8 109.1    10.2      M    M
 29000  -30.5 -22.9   295   32   16   8.2   4.5   42.2 107.9     9.8      M    M
 28000  -28.3 -18.9   295   31   16   7.4   4.1   41.3 106.4     9.3      M    M
 27000  -25.7 -14.3   300   29   15   8.6   4.7   40.8 105.4     9.0      M    M
 26000  -23.4 -10.1   300   28   15   7.6   4.1   40.0 104.0     8.4      M    M
 25000  -21.1  -6.0   300   27   14   7.5   4.1   39.2 102.6     7.9      M    M
 24000  -19.0  -2.2   290   24   12   6.9   3.8   38.1 100.6     7.1      M    M
 23000  -17.0   1.4   280   23   12   7.6   4.2   37.1  98.8     6.3      M    M
 22000  -14.4   6.1   285   23   12   8.5   4.7   36.7  98.1     6.1      M    M
 21000  -12.6   9.3   290   22   11   5.4   3.0   35.3  95.6     5.0      M    M
 20000  -11.7  10.9   295   22   11   1.4   0.7   33.0  91.4     3.0      M    M
 19500  -11.6  11.1   295   23   12   5.7   3.1   31.7  89.0     1.7      M    M
 19000  -10.5  13.1   295   23   12   7.6   4.1   31.3  88.3     1.3      M    M
 18500   -9.6  14.7   295   22   11   5.1   2.8   30.7  87.2     0.8      M    M
 18000   -8.8  16.2   295   20   11   7.7   4.2   30.0  86.0     0.1      M    M
 17500   -7.4  18.7   295   19   10   9.1   5.0   29.9  85.8    -0.0   1206  6.1
 17000   -5.4  22.3   300   18    9   9.2   5.0   29.7  85.5    -0.2   1122  5.7
 16500   -4.0  24.8   300   17    9   9.1   5.0   29.7  85.4    -0.2   1066  5.4
 16000   -2.6  27.3   300   16    8   8.9   4.9   29.5  85.1    -0.3   1011  5.1
 15500   -1.3  29.7   305   15    8   8.9   4.9   29.4  84.9    -0.5    955  4.9
 15000    0.0  32.0   315   15    8   8.8   4.8   29.2  84.6    -0.6    901  4.6
 14500    1.3  34.3   320   15    8   8.8   4.8   29.1  84.3    -0.8    848  4.3
 14000    2.6  36.7   325   15    8   8.8   4.8   28.9  84.1    -0.9    794  4.0
 13500    3.9  39.0   330   15    8   8.8   4.9   28.8  83.8    -1.2    741  3.8
 13000    5.2  41.4   330   15    8   8.9   4.9   28.6  83.5    -1.4    687  3.5
 12500    6.5  43.7   335   15    8   8.9   4.9   28.5  83.2    -1.5    634  3.2
 12000    7.8  46.0   335   15    8   9.2   5.0   28.4  83.0    -1.7    580  2.9
 11500    9.2  48.6   335   15    8   9.3   5.1   28.3  82.9    -1.8    523  2.7
 11000   10.6  51.1   335   14    7   9.3   5.1   28.2  82.8    -1.9    467  2.4
 10500   12.0  53.6   335   14    7   9.2   5.1   28.2  82.7    -1.9    410  2.1
 10250   12.6  54.7   335   14    7   9.0   5.0   28.1  82.6    -2.0    383  1.9
 10000   13.3  55.9   330   14    7   9.1   5.0   28.0  82.5    -2.1    355  1.8
  9750   14.0  57.2   330   13    7   9.1   5.0   28.0  82.4    -2.1    328  1.7
  9500   14.7  58.5   330   13    7   9.1   5.0   27.9  82.3    -2.2    300  1.5
  9250   15.3  59.5   325   13    7   9.1   5.0   27.9  82.2    -2.2    273  1.4
  9000   16.0  60.8   325   13    7   9.1   5.0   27.9  82.2    -2.3    245  1.2
  8750   16.7  62.1   325   12    6   9.1   5.0   27.8  82.1    -2.4    217  1.1
  8500   17.3  63.1   330   12    6   9.1   5.0   27.7  81.9    -2.4    190  1.0
  8250   18.0  64.4   330   11    6   9.1   5.0   27.7  81.8    -2.5    162  0.8
  8000   18.7  65.7   335   11    6   9.0   4.9   27.6  81.8    -2.6    135  0.7
  7750   19.4  66.9   325   11    6   9.5   5.2   27.6  81.6    -2.6    107  0.5
  7500   20.0  68.0   320   12    6   7.5   4.1   27.5  81.5    -2.7     80  0.4
  7250   20.4  68.7   310   13    7   5.0   2.8   27.2  81.0    -3.0     60  0.3
  7000   20.8  69.4   305   14    7   3.7   2.0   26.8  80.3    -3.4     43  0.2
  6750   21.1  70.0   290   12    6   8.0   4.4   26.4  79.6    -3.9     26  0.1
  6500   21.4  70.5   265   11    6  -7.9  -4.3   26.1  78.9    -4.3      9  0.0
  6250   20.0  68.0   245   11    6 -17.2  -9.5   23.9  75.1    -6.4     43  0.2
  6000   19.3  66.7   225   14    7  -3.4  -1.9   22.5  72.6    -7.8     56  0.3
  5750   18.9  66.0   225   10    5  -8.8  -4.8   21.4  70.6    -9.0     61  0.3
  5500   17.0  62.6   225    5    2 -45.0 -24.7   19.0  66.1   -11.7    112  0.6

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

           09/16/2014 at 0900 MDT          |       09/16/2014 at 1200 MDT
                                           |
K index... +16.5  LI... 0.0                | K index... +17.2  LI... -1.2
CAPE... 0.0  CIN... M                      | CAPE... +48.4  CIN... -50.8
                                           |
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 -65.8 -86.4  290  49 25   2.3   1.2 | -65.8 -86.4  290  48 25   2.6   1.4
 45000 -61.6 -78.9  290  66 34   4.3   2.4 | -61.5 -78.7  290  59 30   3.4   1.9
 40000 -54.8 -66.6  295  56 29   6.6   3.6 | -56.0 -68.8  290  53 27   7.4   4.0
 38000 -50.9 -59.6  300  52 27   6.5   3.6 | -51.7 -61.1  295  52 27   7.2   3.9
 36000 -47.0 -52.6  305  49 25   6.5   3.6 | -47.3 -53.1  305  52 27   7.2   3.9
 34000 -42.2 -44.0  305  43 22   7.4   4.0 | -42.6 -44.7  305  46 24   8.1   4.4
 32000 -37.8 -36.0  305  36 19   7.2   4.0 | -37.1 -34.8  305  39 20   8.0   4.4
 30000 -32.8 -27.0  305  32 16   8.4   4.6 | -32.2 -26.0  300  32 17   8.1   4.5
 29000 -30.3 -22.5  305  30 15   8.4   4.6 | -29.8 -21.6  295  29 15   8.1   4.5
 28000 -27.8 -18.0  300  28 14   8.0   4.4 | -27.4 -17.3  295  27 14   7.9   4.3
 27000 -25.5 -13.9  300  26 14   7.8   4.3 | -25.0 -13.0  295  26 13   7.7   4.2
 26000 -23.1  -9.6  300  25 13   7.8   4.3 | -22.7  -8.9  295  25 13   7.7   4.2
 25000 -20.8  -5.4  300  23 12   7.8   4.3 | -20.4  -4.7  290  24 12   7.6   4.2
 24000 -18.7  -1.7  300  21 11   6.5   3.6 | -18.5  -1.3  290  22 11   6.2   3.4
 23000 -16.8   1.8  305  20 10   6.5   3.6 | -16.6   2.1  290  21 11   6.2   3.4
 22000 -14.8   5.4  305  18  9   6.3   3.4 | -14.8   5.4  285  20 10   6.1   3.3
 21000 -13.2   8.2  305  18  9   5.3   2.9 | -13.1   8.4  290  20 10   5.6   3.1
 20000 -11.7  10.9  305  17  9   5.4   3.0 | -11.4  11.5  300  21 11   5.7   3.1
 19500 -10.9  12.4  305  17  9   5.4   2.9 | -10.6  12.9  300  22 11   5.5   3.0
 19000 -10.0  14.0  305  16  8   7.5   4.1 |  -9.6  14.7  305  22 11   8.2   4.5
 18500  -8.9  16.0  305  15  8   7.4   4.1 |  -8.5  16.7  305  22 11   8.0   4.4
 18000  -7.8  18.0  305  13  7   7.7   4.3 |  -7.3  18.9  310  22 12   8.2   4.5
 17500  -6.6  20.1  305  14  7   8.3   4.5 |  -6.1  21.0  310  23 12   8.4   4.6
 17000  -5.4  22.3  305  14  7   8.3   4.6 |  -4.8  23.4  310  23 12   8.4   4.6
 16500  -3.6  25.5  300  14  7   8.3   4.6 |  -3.1  26.4  310  22 11   8.1   4.4
 16000  -2.3  27.9  300  14  7   8.4   4.6 |  -1.9  28.6  310  21 11   8.1   4.5
 15500  -1.1  30.0  295  13  7   8.8   4.8 |  -0.7  30.7  310  20 10   8.1   4.4
 15000   0.2  32.4  295  13  7   8.8   4.8 |   0.5  32.9  310  19 10   8.1   4.4
 14500   1.5  34.7  300  13  7   8.8   4.8 |   1.7  35.1  315  17  9   8.4   4.6
 14000   2.8  37.0  300  13  7   8.8   4.8 |   2.9  37.2  315  16  8   8.4   4.6
 13500   4.1  39.4  305  12  6   9.2   5.0 |   4.2  39.6  315  15  8   8.6   4.7
 13000   5.5  41.9  310  13  6   9.3   5.1 |   5.5  41.9  320  14  7   8.6   4.7
 12500   6.9  44.4  310  13  7   9.2   5.1 |   6.7  44.1  320  13  7   8.7   4.8
 12000   8.2  46.8  315  13  7   9.2   5.0 |   8.0  46.4  320  12  6   8.8   4.8
 11500   9.6  49.3  315  13  7   9.1   5.0 |   9.3  48.7  320  11  6   9.0   4.9
 11000  10.9  51.6  320  13  7   8.7   4.8 |  10.6  51.1  320  11  6   8.7   4.8
 10500  12.3  54.1  320  14  7   4.1   2.3 |  12.0  53.6  320  11  5   3.7   2.0
 10250  12.4  54.3  320  14  7   5.9   3.3 |  12.1  53.8  320  10  5   5.4   2.9
 10000  13.3  55.9  320  14  7  13.3   7.3 |  12.9  55.2  325  10  5  13.4   7.3
  9750  14.2  57.6  320  14  7  11.9   6.5 |  13.8  56.8  325  10  5  11.8   6.5
  9500  15.0  59.0  320  13  7   9.3   5.1 |  14.6  58.3  330  10  5   9.2   5.1
  9250  15.5  59.9  320  13  7   6.8   3.7 |  15.1  59.2  330  10  5   6.9   3.8
  9000  16.1  61.0  320  13  7   9.6   5.2 |  15.8  60.4  330  10  5   9.7   5.3
  8750  16.9  62.4  320  13  7  10.4   5.7 |  16.5  61.7  330  10  5  10.3   5.7
  8500  17.6  63.7  320  13  7   9.1   5.0 |  17.3  63.1  330   9  5   9.5   5.2
  8250  18.2  64.8  320  13  7   8.2   4.5 |  17.9  64.2  330  10  5   9.0   4.9
  8000  18.9  66.0  320  13  7   8.6   4.7 |  18.6  65.5  335  10  5   9.4   5.1
  7750  19.5  67.1  320  13  6   8.5   4.6 |  19.3  66.7  335   9  5   9.6   5.2
  7500  20.1  68.2  315  12  6   7.7   4.2 |  20.0  68.0  330   9  5   9.4   5.2
  7250  20.6  69.1  315  12  6   7.2   4.0 |  20.7  69.3  330   8  4   9.4   5.2
  7000  21.1  70.0  315  12  6   8.1   4.4 |  21.4  70.5  330   8  4   9.3   5.1
  6750  21.7  71.1  310  12  6   5.0   2.8 |  22.0  71.6  325   7  4   9.8   5.4
  6500  21.9  71.4  305  12  6   0.3   0.1 |  22.8  73.0  320   7  3  10.5   5.8
  6250  21.9  71.4  300  12  6   3.4   1.9 |  23.5  74.3  320   6  3  10.0   5.5
  6000  22.0  71.6  295  12  6  -7.6  -4.2 |  24.3  75.7  320   6  3  11.7   6.4
  5750  20.6  69.1  285   9  5 -19.8 -10.9 |  25.3  77.5  320   6  3  15.8   8.7
  5500  19.3  66.7  265   6  3  -7.1  -3.9 |  26.6  79.9  320   6  3  17.8   9.8

           09/16/2014 at 1500 MDT          |       09/16/2014 at 1800 MDT
                                           |
K index... +19.2  LI... -1.4               | K index... +20.9  LI... -0.4
CAPE... +40.0  CIN... -41.4                | CAPE... 0.0  CIN... -30.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.3 -85.5  290  52 27   2.3   1.3 | -66.1 -87.0  295  57 29   1.8   1.0
 45000 -61.5 -78.7  295  63 32   3.3   1.8 | -62.2 -80.0  290  69 35   4.7   2.6
 40000 -56.0 -68.8  295  54 28   7.7   4.2 | -54.8 -66.6  290  54 28   6.9   3.8
 38000 -51.5 -60.7  295  51 26   7.5   4.1 | -50.8 -59.4  290  51 26   6.8   3.7
 36000 -47.0 -52.6  305  48 25   7.5   4.1 | -46.7 -52.1  295  48 25   6.8   3.7
 34000 -41.6 -42.9  305  43 22   8.2   4.5 | -41.2 -42.2  295  42 22   8.4   4.6
 32000 -36.7 -34.1  305  39 20   8.2   4.5 | -36.1 -33.0  295  37 19   8.4   4.6
 30000 -32.0 -25.6  300  35 18   7.8   4.3 | -31.4 -24.5  300  36 18   7.8   4.3
 29000 -29.6 -21.3  300  34 17   7.8   4.3 | -29.0 -20.2  300  35 18   7.8   4.3
 28000 -27.3 -17.1  295  33 17   7.8   4.3 | -26.7 -16.1  300  35 18   7.5   4.1
 27000 -24.9 -12.8  295  31 16   7.9   4.3 | -24.5 -12.1  300  33 17   7.3   4.0
 26000 -22.5  -8.5  300  29 15   7.9   4.3 | -22.3  -8.1  305  32 17   7.3   4.0
 25000 -20.2  -4.4  305  27 14   7.7   4.2 | -20.1  -4.2  305  31 16   7.3   4.0
 24000 -18.2  -0.8  305  25 13   6.3   3.5 | -18.0  -0.4  310  28 14   6.9   3.8
 23000 -16.3   2.7  300  24 12   6.3   3.5 | -15.9   3.4  310  24 12   6.9   3.8
 22000 -14.4   6.1  300  23 12   6.1   3.3 | -13.9   7.0  310  20 11   6.6   3.6
 21000 -12.8   9.0  295  23 12   5.3   2.9 | -12.3   9.9  310  21 11   5.2   2.8
 20000 -11.2  11.8  290  23 12   5.4   2.9 | -10.7  12.7  305  23 12   5.2   2.8
 19500 -10.4  13.3  290  23 12   5.1   2.8 | -10.0  14.0  305  23 12   4.9   2.7
 19000  -9.4  15.1  290  23 12   8.4   4.6 |  -9.0  15.8  305  23 12   8.7   4.8
 18500  -8.2  17.2  290  24 12   8.3   4.5 |  -7.7  18.1  300  23 12   8.7   4.8
 18000  -7.0  19.4  295  25 13   8.6   4.7 |  -6.5  20.3  300  22 11   8.7   4.8
 17500  -5.7  21.7  295  25 13   9.1   5.0 |  -5.2  22.6  300  21 11   8.7   4.8
 17000  -4.4  24.1  300  24 13   9.2   5.1 |  -3.4  25.9  300  20 10   8.7   4.8
 16500  -2.4  27.7  305  23 12   9.0   4.9 |  -2.1  28.2  300  19 10   8.6   4.7
 16000  -1.1  30.0  305  22 11   9.0   4.9 |  -0.9  30.4  300  18  9   8.7   4.8
 15500   0.1  32.2  305  21 11   8.5   4.6 |   0.3  32.5  305  16  8   8.3   4.6
 15000   1.4  34.5  310  19 10   8.6   4.7 |   1.5  34.7  305  15  8   8.4   4.6
 14500   2.6  36.7  310  18  9   8.0   4.4 |   2.7  36.9  305  13  7   7.9   4.3
 14000   3.7  38.7  315  17  9   8.0   4.4 |   3.8  38.8  310  11  5   7.8   4.3
 13500   4.9  40.8  315  15  8   8.0   4.4 |   5.0  41.0  315   8  4   7.8   4.3
 13000   6.0  42.8  320  14  7   8.1   4.4 |   6.1  43.0  330   7  3   7.8   4.3
 12500   7.2  45.0  325  13  7   8.5   4.7 |   7.3  45.1  355   5  3   7.8   4.3
 12000   8.5  47.3  330  11  6   8.8   4.8 |   8.5  47.3  015   6  3   7.8   4.3
 11500   9.8  49.6  335  10  5   8.6   4.7 |   9.7  49.5  030   6  3   8.2   4.5
 11000  11.1  52.0  340   8  4   8.1   4.4 |  11.0  51.8  030   6  3   8.7   4.8
 10500  12.3  54.1  350   7  4   3.8   2.1 |  12.3  54.1  035   6  3   4.7   2.6
 10250  12.4  54.3  350   7  4   5.5   3.0 |  12.5  54.5  035   6  3   6.4   3.5
 10000  13.2  55.8  355   7  3  12.2   6.7 |  13.4  56.1  035   6  3  12.7   7.0
  9750  14.0  57.2  360   6  3  11.0   6.0 |  14.2  57.6  035   6  3  11.7   6.4
  9500  14.8  58.6  360   6  3   9.4   5.1 |  15.1  59.2  035   6  3   9.5   5.2
  9250  15.4  59.7  360   6  3   8.0   4.4 |  15.6  60.1  035   6  3   7.5   4.1
  9000  16.1  61.0  360   6  3  10.4   5.7 |  16.3  61.3  035   6  3  10.3   5.6
  8750  16.9  62.4  360   6  3  11.2   6.1 |  17.1  62.8  030   6  3  11.3   6.2
  8500  17.7  63.9  360   5  3  10.2   5.6 |  17.9  64.2  030   6  3  10.4   5.7
  8250  18.4  65.1  360   5  3   9.2   5.0 |  18.6  65.5  030   6  3   9.9   5.4
  8000  19.2  66.6  360   5  3  10.3   5.7 |  19.4  66.9  025   6  3   9.8   5.4
  7750  20.0  68.0  360   5  3  11.1   6.1 |  20.1  68.2  025   6  3   9.5   5.2
  7500  20.8  69.4  360   5  3  10.1   5.6 |  20.8  69.4  020   6  3   9.6   5.2
  7250  21.5  70.7  360   5  3   9.9   5.4 |  21.5  70.7  020   6  3   9.5   5.2
  7000  22.2  72.0  360   5  3   9.4   5.2 |  22.3  72.1  015   6  3   9.5   5.2
  6750  22.9  73.2  360   5  3   9.5   5.2 |  23.0  73.4  015   6  3   9.7   5.3
  6500  23.7  74.7  360   5  3  10.5   5.8 |  23.7  74.7  015   6  3   9.8   5.4
  6250  24.5  76.1  360   5  3  11.0   6.1 |  24.4  75.9  010   6  3   9.9   5.5
  6000  25.3  77.5  360   5  3   9.9   5.5 |  25.2  77.4  010   6  3   9.4   5.2
  5750  26.1  79.0  360   5  2  13.3   7.3 |  25.9  78.6  010   6  3   9.3   5.1
  5500  27.4  81.3  360   5  3  21.9  12.0 |  26.5  79.7  005   5  3  10.6   5.8
________________________________________________________________________________

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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