Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301326
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0726 MDT Sunday, August 30, 2015

This forecast is for Sunday, August 30, 2015:

If the trigger temperature of 87.3 F/30.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1094 ft/min (5.6 m/s)
   Maximum height of thermals.................. 18660 ft MSL (13375 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12028 ft MSL (6743 ft AGL)
Thermal soaring outlook for Monday 08/31....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18105 ft MSL (12820 ft AGL)
Wave soaring outlook for Monday 08/31.......... Poor

Remarks... Scattered afternoon storms

Sunrise/Sunset.................... 06:25:25 / 19:35:31 MDT
Total possible sunshine........... 13 hr 10 min 6 sec (790 min 6 sec)
Altitude of sun at 13:00:02 MDT... 59.13 degrees

Upper air data from rawinsonde observation taken on 08/30/2015 at 0600 MDT

Freezing level.................. 15838 ft MSL (10553 ft AGL)
Convective condensation level... 17094 ft MSL (11809 ft AGL)
Lifted condensation level....... 18285 ft MSL (13000 ft AGL)
Lifted index.................... +0.8
K index......................... +20.7

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  -71.3 -96.3   305   32   17 -14.3  -7.9   73.1 163.5    22.5      M    M
 45000  -65.1 -85.2   310   24   12   7.5   4.1   58.9 138.0    15.3      M    M
 40000  -53.6 -64.5   290   14    7   7.4   4.1   54.1 129.3    13.2      M    M
 38000  -48.3 -54.9   290   12    6   9.7   5.3   53.4 128.2    13.1      M    M
 36000  -43.1 -45.6   295   18    9   9.2   5.0   52.5 126.4    12.7      M    M
 34000  -38.3 -36.9   295    5    3   7.0   3.8   49.9 121.9    11.3      M    M
 32000  -33.4 -28.1   245    7    4   8.2   4.5   48.6 119.4    10.5      M    M
 30000  -28.7 -19.7   275    9    5   7.9   4.4   47.3 117.1     9.8      M    M
 29000  -26.3 -15.3   265    8    4   7.9   4.4   46.3 115.3     9.2      M    M
 28000  -23.9 -11.0   255    7    4   8.0   4.4   45.5 113.8     8.6      M    M
 27000  -21.5  -6.7   240    7    3   8.0   4.4   44.8 112.6     8.2      M    M
 26000  -19.1  -2.4   230    7    3   8.0   4.4   44.2 111.5     7.8      M    M
 25000  -16.7   1.9   215    7    4   7.9   4.3   43.7 110.7     7.5      M    M
 24000  -14.4   6.1   210    5    3   7.5   4.1   43.0 109.4     7.0      M    M
 23000  -12.5   9.5   200    3    2   6.2   3.4   41.8 107.3     6.1      M    M
 22000  -10.6  12.9   185    7    4   6.2   3.4   40.5 104.9     5.1      M    M
 21000   -8.7  16.3   180   12    6   6.2   3.4   39.3 102.8     4.1      M    M
 20000   -6.9  19.6   205   11    6   6.2   3.4   38.0 100.5     3.1      M    M
 19500   -5.9  21.4   210   11    6   6.9   3.8   37.4  99.4     2.5      M    M
 19000   -5.2  22.6   235   11    6   4.6   2.5   36.7  98.1     1.8      M    M
 18500   -5.9  21.4   245   13    7 -12.8  -7.0   34.5  94.1    -0.4   1299  6.6
 18000   -6.2  20.8   245   16    8  10.6   5.8   32.7  90.9    -2.1   1292  6.6
 17500   -5.0  23.0   240   15    8   8.4   4.6   32.4  90.4    -2.4   1241  6.3
 17000   -3.7  25.3   235   14    7   9.4   5.2   32.3  90.1    -2.6   1188  6.0
 16500   -1.6  29.1   225   11    6   9.7   5.3   32.2  90.0    -2.7   1102  5.6
 16000   -0.1  31.8   220   10    5   9.7   5.3   32.2  90.0    -2.7   1044  5.3
 15500    1.3  34.3   220    9    5   9.7   5.3   32.2  89.9    -2.8    985  5.0
 15000    2.8  37.0   225    8    4   9.7   5.3   32.2  89.9    -2.8    927  4.7
 14500    4.2  39.6   225    7    3   9.6   5.3   32.2  90.0    -2.8    868  4.4
 14000    5.7  42.3   230    6    3   9.5   5.2   32.2  89.9    -2.8    811  4.1
 13500    7.1  44.8   235    4    2   9.5   5.2   32.1  89.8    -2.9    753  3.8
 13000    8.5  47.3   240    3    1   9.5   5.2   32.1  89.7    -3.0    696  3.5
 12500    9.9  49.8   260    1    1   9.5   5.2   32.0  89.7    -3.0    638  3.2
 12000   11.4  52.5   310    1    1   9.5   5.2   32.0  89.6    -3.0    580  2.9
 11500   12.8  55.0   295    6    3   9.5   5.2   32.0  89.5    -3.1    523  2.7
 11000   14.2  57.6   290   10    5   9.3   5.1   31.9  89.4    -3.1    465  2.4
 10500   15.7  60.3   290   10    5   9.8   5.4   31.9  89.4    -3.2    407  2.1
 10250   16.3  61.3   305   11    6   8.8   4.9   31.9  89.3    -3.2    379  1.9
 10000   17.0  62.6   315   12    6   8.8   4.8   31.8  89.2    -3.3    353  1.8
  9750   17.6  63.7   315   12    6   8.8   4.8   31.7  89.1    -3.4    326  1.7
  9500   18.3  64.9   310   13    6   8.8   4.8   31.6  88.9    -3.5    299  1.5
  9250   18.9  66.0   310   13    7   8.8   4.8   31.6  88.8    -3.6    273  1.4
  9000   19.6  67.3   310   13    7   8.8   4.8   31.5  88.7    -3.7    246  1.2
  8750   20.2  68.4   310   13    7   8.8   4.8   31.4  88.5    -3.8    219  1.1
  8500   20.8  69.4   310   12    6   8.8   4.9   31.3  88.4    -3.9    193  1.0
  8250   21.5  70.7   315   12    6   8.6   4.7   31.3  88.3    -4.0    166  0.8
  8000   22.1  71.8   315   12    6   9.4   5.2   31.2  88.2    -4.1    139  0.7
  7750   22.8  73.0   310   11    6   6.6   3.6   31.1  88.0    -4.2    113  0.6
  7500   23.0  73.4   305   10    5   1.2   0.7   30.6  87.1    -4.7     98  0.5
  7250   23.0  73.4   300   10    5   0.2   0.1   29.9  85.8    -5.4     91  0.5
  7000   23.0  73.4   290    9    5   0.5   0.3   29.2  84.6    -6.2     83  0.4
  6750   23.0  73.4   265    9    4   0.5   0.3   28.5  83.3    -6.9     76  0.4
  6500   23.0  73.4   240   10    5   0.3   0.1   27.8  82.0    -7.7     68  0.3
  6250   23.0  73.4   225   13    6   1.2   0.7   27.1  80.7    -8.4     61  0.3
  6000   23.0  73.4   215   16    8  -2.3  -1.3   26.4  79.5    -9.2     54  0.3
  5750   22.3  72.1   215   13    6 -17.8  -9.8   25.0  76.9   -10.7     68  0.3
  5500   20.2  68.4   215    9    5 -32.6 -17.9   22.2  72.0   -13.5    122  0.6

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

           08/30/2015 at 0900 MDT          |       08/30/2015 at 1200 MDT
                                           |
K index... +19.5  LI... +2.6               | K index... +10.7  LI... +1.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.1
                                           |
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 -66.7 -88.1  295  20 10  -0.9  -0.5 | -66.9 -88.4  280  25 13  -0.8  -0.4
 45000 -64.1 -83.4  310  28 15   7.1   3.9 | -64.1 -83.4  295  31 16   7.2   4.0
 40000 -53.3 -63.9  300  14  7   8.0   4.4 | -53.1 -63.6  270  13  6   7.9   4.3
 38000 -48.5 -55.3  305  15  8   8.0   4.4 | -48.4 -55.1  275  11  6   7.9   4.3
 36000 -43.7 -46.7  310  17  9   8.0   4.4 | -43.7 -46.7  285  10  5   7.9   4.3
 34000 -38.9 -38.0  300  12  6   8.0   4.4 | -39.0 -38.2  270  11  6   7.8   4.3
 32000 -34.1 -29.4  275   8  4   8.0   4.4 | -33.8 -28.8  255  12  6   8.0   4.4
 30000 -29.0 -20.2  250   8  4   7.6   4.1 | -29.1 -20.4  245  13  7   7.8   4.3
 29000 -26.7 -16.1  245   9  5   7.6   4.1 | -26.8 -16.2  235  13  7   7.8   4.3
 28000 -24.4 -11.9  240   9  5   8.2   4.5 | -24.4 -11.9  230  14  7   7.8   4.3
 27000 -22.0  -7.6  235  10  5   8.1   4.4 | -22.1  -7.8  230  14  7   7.8   4.3
 26000 -19.6  -3.3  230  10  5   8.1   4.4 | -19.8  -3.6  225  14  7   7.8   4.3
 25000 -17.1   1.2  225  10  5   7.7   4.2 | -17.4   0.7  220  14  7   7.7   4.2
 24000 -15.0   5.0  225  11  6   7.2   4.0 | -15.2   4.6  220  14  7   7.5   4.1
 23000 -12.8   9.0  225  11  6   7.3   4.0 | -12.9   8.8  225  15  8   7.5   4.1
 22000 -10.7  12.7  225  12  6   6.4   3.5 | -10.7  12.7  225  15  8   6.3   3.4
 21000  -9.0  15.8  235  11  6   5.6   3.1 |  -9.2  15.4  235  12  6   5.1   2.8
 20000  -7.4  18.7  245  10  5   5.7   3.1 |  -7.7  18.1  250  10  5   5.1   2.8
 19500  -6.6  20.1  250  10  5   5.8   3.2 |  -6.9  19.6  260   9  5   5.0   2.7
 19000  -5.8  21.6  255  10  5   5.2   2.9 |  -6.0  21.2  265  10  5   7.7   4.2
 18500  -5.0  23.0  255  10  5   5.4   2.9 |  -4.9  23.2  260  11  6   7.4   4.1
 18000  -4.3  24.3  260  10  5   6.1   3.3 |  -3.8  25.2  260  13  7   6.6   3.6
 17500  -3.4  25.9  255  11  6   7.0   3.8 |  -2.9  26.8  255  13  7   6.0   3.3
 17000  -2.5  27.5  250  11  6   7.3   4.0 |  -2.1  28.2  250  14  7   6.0   3.3
 16500  -1.5  29.3  245  11  6   7.5   4.1 |  -0.4  31.3  240  13  6   8.1   4.5
 16000   0.2  32.4  245   8  4   7.5   4.1 |   0.8  33.4  235  12  6   8.2   4.5
 15500   1.4  34.5  250   7  3   7.7   4.2 |   2.0  35.6  235  10  5   8.2   4.5
 15000   2.6  36.7  250   6  3   7.6   4.2 |   3.2  37.8  230   9  5   8.3   4.5
 14500   3.9  39.0  255   5  2   9.2   5.0 |   4.3  39.7  230   8  4   8.0   4.4
 14000   5.3  41.5  270   4  2   9.2   5.1 |   5.5  41.9  225   7  4   8.0   4.4
 13500   6.7  44.1  285   4  2   8.9   4.9 |   6.7  44.1  225   6  3   8.8   4.8
 13000   8.0  46.4  305   5  2   8.8   4.8 |   8.0  46.4  230   5  2   9.0   5.0
 12500   9.3  48.7  315   5  3   8.9   4.9 |   9.4  48.9  235   3  2   9.0   4.9
 12000  10.6  51.1  320   6  3   9.0   5.0 |  10.7  51.3  250   2  1   9.0   4.9
 11500  11.9  53.4  325   7  4   9.1   5.0 |  12.0  53.6  285   1  1   9.1   5.0
 11000  13.3  55.9  325   9  4   9.1   5.0 |  13.4  56.1  315   2  1   9.1   5.0
 10500  14.6  58.3  325  10  5   5.3   2.9 |  14.7  58.5  325   3  1   5.2   2.9
 10250  14.9  58.8  325  10  5   6.5   3.6 |  15.0  59.0  325   3  1   6.2   3.4
 10000  15.7  60.3  325  11  6  12.3   6.7 |  15.8  60.4  320   3  2  12.0   6.6
  9750  16.5  61.7  320  12  6  11.3   6.2 |  16.6  61.9  320   4  2  10.8   5.9
  9500  17.4  63.3  320  14  7   9.5   5.2 |  17.4  63.3  320   4  2   9.7   5.3
  9250  17.9  64.2  315  15  8   7.1   3.9 |  18.0  64.4  320   5  2   8.4   4.6
  9000  18.5  65.3  315  16  8   8.8   4.9 |  18.7  65.7  315   5  3   9.7   5.3
  8750  19.2  66.6  310  17  9   9.6   5.3 |  19.4  66.9  315   6  3  10.0   5.5
  8500  19.9  67.8  305  19 10   9.0   4.9 |  20.2  68.4  315   6  3   9.8   5.4
  8250  20.6  69.1  305  20 10   8.6   4.7 |  20.9  69.6  310   6  3   9.7   5.3
  8000  21.2  70.2  305  21 11   8.5   4.7 |  21.6  70.9  310   6  3   9.8   5.4
  7750  21.8  71.2  300  21 11   8.2   4.5 |  22.2  72.0  305   6  3   9.8   5.4
  7500  22.5  72.5  300  21 11   8.2   4.5 |  22.9  73.2  300   5  3  10.3   5.6
  7250  23.1  73.6  300  20 10   7.9   4.3 |  23.7  74.7  300   5  3  10.9   6.0
  7000  23.7  74.7  300  20 10   8.4   4.6 |  24.5  76.1  295   5  3  10.0   5.5
  6750  24.3  75.7  300  19 10   6.2   3.4 |  25.2  77.4  295   5  3   9.1   5.0
  6500  24.4  75.9  300  17  9  -1.2  -0.6 |  25.9  78.6  295   5  2  10.2   5.6
  6250  24.1  75.4  295  14  7  -2.9  -1.6 |  26.7  80.1  295   5  2  11.6   6.3
  6000  23.8  74.8  295  10  5  -6.6  -3.6 |  27.5  81.5  295   5  2   9.6   5.3
  5750  23.1  73.6  280   7  4  -4.9  -2.7 |  28.3  82.9  295   5  2  13.8   7.6
  5500  23.3  73.9  260   5  3  14.6   8.0 |  29.8  85.6  295   5  2  26.5  14.5

           08/30/2015 at 1500 MDT          |       08/30/2015 at 1800 MDT
                                           |
K index... +17.4  LI... +1.8               | K index... +24.8  LI... -0.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -11.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -67.2 -89.0  265  24 13  -0.7  -0.4 | -66.5 -87.7  260  26 14  -0.8  -0.5
 45000 -64.1 -83.4  280  30 15   7.5   4.1 | -63.8 -82.8  275  33 17   6.9   3.8
 40000 -52.8 -63.0  255  20 10   7.9   4.3 | -53.1 -63.6  265  29 15   8.2   4.5
 38000 -48.0 -54.4  250  17  9   7.9   4.3 | -48.2 -54.8  260  27 14   8.2   4.5
 36000 -43.3 -45.9  240  14  7   7.8   4.3 | -43.3 -45.9  250  25 13   8.2   4.5
 34000 -38.7 -37.7  245  15  8   7.7   4.2 | -38.4 -37.1  255  23 12   8.1   4.5
 32000 -34.1 -29.4  245  15  8   7.6   4.2 | -33.6 -28.5  255  21 11   8.1   4.4
 30000 -28.9 -20.0  240  16  8   7.6   4.2 | -28.3 -18.9  250  19 10   7.7   4.2
 29000 -26.7 -16.1  235  16  8   7.6   4.2 | -26.0 -14.8  250  17  9   7.7   4.2
 28000 -24.4 -11.9  235  16  8   7.5   4.1 | -23.8 -10.8  245  16  8   7.0   3.9
 27000 -22.2  -8.0  230  16  8   7.5   4.1 | -21.6  -6.9  245  16  8   7.1   3.9
 26000 -19.9  -3.8  230  16  8   7.5   4.1 | -19.5  -3.1  240  16  8   7.1   3.9
 25000 -17.7   0.1  230  16  8   7.6   4.2 | -17.4   0.7  235  16  8   7.0   3.8
 24000 -15.4   4.3  235  16  8   7.6   4.2 | -15.4   4.3  240  15  8   6.8   3.7
 23000 -13.1   8.4  240  15  8   7.6   4.2 | -13.4   7.9  245  14  7   6.9   3.8
 22000 -10.9  12.4  245  15  8   6.6   3.6 | -11.4  11.5  250  14  7   6.4   3.5
 21000  -9.2  15.4  255  14  7   5.7   3.1 |  -9.8  14.4  255  13  7   5.6   3.1
 20000  -7.5  18.5  265  14  7   5.7   3.1 |  -8.2  17.2  265  13  6   5.7   3.1
 19500  -6.7  19.9  265  14  7   5.6   3.1 |  -7.4  18.7  270  12  6   5.5   3.0
 19000  -5.7  21.7  270  14  7   7.4   4.1 |  -6.4  20.5  270  12  6   8.5   4.6
 18500  -4.7  23.5  275  15  8   7.4   4.1 |  -5.3  22.5  275  11  6   8.2   4.5
 18000  -3.6  25.5  275  16  8   7.7   4.2 |  -4.1  24.6  275  10  5   8.4   4.6
 17500  -2.5  27.5  275  16  8   7.9   4.4 |  -2.8  27.0  280  10  5   8.7   4.8
 17000  -1.4  29.5  275  17  9   8.1   4.4 |  -1.5  29.3  280   9  5   8.8   4.8
 16500  -0.3  31.5  280  16  8   8.2   4.5 |  -0.3  31.5  275   8  4   8.1   4.4
 16000   1.5  34.7  280  14  7   8.2   4.5 |   1.5  34.7  270   7  3   8.2   4.5
 15500   2.7  36.9  285  12  6   8.1   4.4 |   2.8  37.0  260   5  3   8.8   4.8
 15000   3.9  39.0  285  10  5   8.1   4.4 |   4.1  39.4  240   5  2   8.8   4.8
 14500   5.2  41.4  285   8  4   8.2   4.5 |   5.4  41.7  215   5  2   9.0   4.9
 14000   6.4  43.5  285   6  3   8.2   4.5 |   6.8  44.2  195   5  3   9.0   5.0
 13500   7.6  45.7  275   4  2   8.6   4.7 |   8.1  46.6  180   6  3   9.1   5.0
 13000   8.9  48.0  265   3  2   8.8   4.8 |   9.5  49.1  175   7  3   9.2   5.0
 12500  10.3  50.5  245   3  1   8.7   4.8 |  10.9  51.6  170   7  4   9.2   5.0
 12000  11.5  52.7  220   3  1   8.5   4.7 |  12.3  54.1  170   8  4   9.2   5.0
 11500  12.8  55.0  200   3  2   8.7   4.8 |  13.7  56.7  170   8  4   8.9   4.9
 11000  14.1  57.4  190   3  2   8.8   4.8 |  14.9  58.8  170   8  4   8.1   4.4
 10500  15.4  59.7  180   4  2   5.5   3.0 |  16.1  61.0  170   8  4  10.8   5.9
 10250  15.7  60.3  180   4  2   6.7   3.7 |  17.1  62.8  165   8  4  11.8   6.5
 10000  16.5  61.7  180   4  2  12.0   6.6 |  17.8  64.0  170   8  4   8.8   4.8
  9750  17.3  63.1  180   4  2  10.8   5.9 |  18.5  65.3  170   8  4   9.7   5.3
  9500  18.2  64.8  180   4  2  10.2   5.6 |  19.2  66.6  170   8  4   9.8   4.9
  9250  18.8  65.8  180   4  2   9.5   5.2 |  19.8  67.6  170   8  4   8.8   4.8
  9000  19.6  67.3  180   4  2  10.6   5.8 |  20.5  68.9  170   7  4   9.5   5.2
  8750  20.4  68.7  180   4  2  10.9   6.0 |  21.2  70.2  170   7  4   9.6   5.3
  8500  21.2  70.2  180   4  2  10.3   5.7 |  22.0  71.6  170   7  4   9.8   5.4
  8250  21.9  71.4  185   4  2   9.6   5.3 |  22.7  72.9  175   6  3  10.4   5.7
  8000  22.7  72.9  185   4  2   9.9   5.4 |  23.5  74.3  175   6  3  10.0   5.5
  7750  23.4  74.1  185   4  2  10.2   5.6 |  24.2  75.6  175   6  3   9.3   5.1
  7500  24.2  75.6  185   4  2  10.2   5.6 |  24.9  76.8  175   6  3   9.7   5.3
  7250  24.9  76.8  185   4  2  10.4   5.7 |  25.6  78.1  180   6  3  10.1   5.5
  7000  25.7  78.3  185   4  2  10.0   5.5 |  26.4  79.5  180   6  3   9.9   5.4
  6750  26.4  79.5  190   4  2   9.6   5.2 |  27.1  80.8  180   5  3   9.3   5.1
  6500  27.2  81.0  190   4  2  10.4   5.7 |  27.8  82.0  185   5  3   9.9   5.4
  6250  28.0  82.4  190   4  2  11.5   6.3 |  28.6  83.5  185   5  3  10.7   5.9
  6000  28.8  83.8  190   4  2  10.0   5.5 |  29.4  84.9  185   5  3  10.2   5.6
  5750  29.6  85.3  195   4  2  13.2   7.2 |  30.1  86.2  185   5  2  10.2   5.6
  5500  31.0  87.8  195   4  2  23.9  13.1 |  31.0  87.8  185   5  2  12.9   7.1
________________________________________________________________________________

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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