Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 261236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Friday, September 26, 2014

This forecast is for Friday, September 26, 2014:

If the trigger temperature of 83.2 F/28.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 678 ft/min (3.4 m/s)
   Maximum height of thermals.................. 12702 ft MSL (7863 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 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................. 6983 ft MSL (2143 ft AGL)
Thermal soaring outlook for Saturday 09/27..... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:05:32 / 19:06:11 MDT
Total possible sunshine........... 12 hr 0 min 40 sec (720 min 40 sec)
Altitude of sun at 13:05:22 MDT... 49.46 degrees

Upper air data from rawinsonde observation taken on 09/26/2014 at 0600 MDT

Freezing level.................. 15585 ft MSL (10746 ft AGL)
Convective condensation level... 16321 ft MSL (11482 ft AGL)
Lifted condensation level....... 15479 ft MSL (10640 ft AGL)
Lifted index.................... +2.2
K index......................... +20.8

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  -70.6 -95.1   235   15    8   8.3   4.5   76.7 170.0    27.0      M    M
 45000  -61.1 -78.0   225   15    8   5.1   2.8   67.0 152.6    23.1      M    M
 40000  -51.9 -61.4   260   17    9   3.8   2.1   58.7 137.6    19.1      M    M
 38000  -47.5 -53.5   255   15    8   7.8   4.3   56.5 133.7    18.2      M    M
 36000  -43.7 -46.7   245   15    8   5.7   3.1   53.5 128.4    16.6      M    M
 34000  -40.5 -40.9   185   14    7   8.4   4.6   49.8 121.7    14.3      M    M
 32000  -34.9 -30.8   190   14    7   8.3   4.6   48.5 119.3    13.7      M    M
 30000  -30.0 -22.0   190   14    7   8.1   4.4   47.2 117.0    13.1      M    M
 29000  -27.6 -17.7   220   17    9   8.1   4.4   46.6 115.8    12.7      M    M
 28000  -25.7 -14.3   210   18    9   4.9   2.7   45.2 113.4    11.8      M    M
 27000  -23.6 -10.5   200   20   10   8.2   4.5   44.0 111.3    11.0      M    M
 26000  -21.2  -6.2   190   22   11   8.3   4.6   43.5 110.2    10.7      M    M
 25000  -18.7  -1.7   185   24   12   8.5   4.7   43.0 109.4    10.5      M    M
 24000  -16.0   3.2   185   22   11   8.8   4.9   42.6 108.8    10.3      M    M
 23000  -13.4   7.9   180   20   10   8.6   4.7   42.3 108.2    10.1      M    M
 22000  -10.8  12.6   175   18    9   7.8   4.3   42.0 107.5     9.9      M    M
 21000   -8.6  16.5   170   17    9   8.6   4.7   41.2 106.1     9.3      M    M
 20000   -6.1  21.0   165   15    8   6.7   3.7   40.7 105.3     9.0      M    M
 19500   -5.2  22.6   150   14    7   5.4   3.0   40.1 104.2     8.6      M    M
 19000   -4.8  23.4   145   13    7   2.0   1.1   38.9 102.0     7.5      M    M
 18500   -5.4  22.3   155   13    6 -24.6 -13.5   36.7  98.1     5.5      M    M
 18000   -7.2  19.0   170   12    6  15.2   8.4   33.1  91.6     2.2      M    M
 17500   -5.7  21.7   185   13    7  10.3   5.7   33.4  92.1     2.3      M    M
 17000   -3.6  25.5   200   15    8   9.1   5.0   33.2  91.8     2.1      M    M
 16500   -2.3  27.9   210   16    8   9.1   5.0   33.1  91.6     2.1      M    M
 16000   -0.9  30.4   215   18    9   9.1   5.0   33.0  91.5     2.0      M    M
 15500    0.5  32.9   215   17    9   9.1   5.0   32.9  91.2     1.9      M    M
 15000    1.9  35.4   215   16    8   9.1   5.0   32.8  91.0     1.8      M    M
 14500    3.2  37.8   220   16    8   8.5   4.7   32.7  90.8     1.8      M    M
 14000    4.1  39.4   220   15    8   5.4   3.0   32.1  89.9     1.2      M    M
 13500    4.8  40.6   225   14    7   6.1   3.3   31.5  88.6     0.4      M    M
 13000    5.9  42.6   235   14    7   8.6   4.7   31.1  88.0     0.1      M    M
 12500    7.2  45.0   240   14    7   8.5   4.7   30.9  87.6    -0.1    652  3.3
 12000    8.4  47.1   245   14    7   7.4   4.1   30.6  87.1    -0.3    601  3.1
 11500    9.4  48.9   245   13    7   7.9   4.3   30.2  86.4    -0.8    557  2.8
 11000   10.7  51.3   250   12    6   8.6   4.7   30.0  86.0    -1.0    504  2.6
 10500   12.0  53.6   250   11    6   8.7   4.8   29.9  85.7    -1.2    451  2.3
 10250   12.6  54.7   250   11    6   9.0   4.9   29.8  85.6    -1.2    423  2.2
 10000   13.3  55.9   250   11    6   9.1   5.0   29.7  85.5    -1.3    396  2.0
  9750   14.0  57.2   250   11    6   9.1   5.0   29.7  85.4    -1.3    368  1.9
  9500   14.6  58.3   255   11    6   9.1   5.0   29.6  85.4    -1.4    341  1.7
  9250   15.3  59.5   255   11    6   9.1   5.0   29.6  85.3    -1.4    313  1.6
  9000   16.0  60.8   255   11    6   9.1   5.0   29.6  85.2    -1.5    285  1.4
  8750   16.7  62.1   255   10    5   9.1   5.0   29.5  85.1    -1.5    258  1.3
  8500   17.3  63.1   250    8    4   9.1   5.0   29.5  85.0    -1.6    230  1.2
  8250   18.0  64.4   250    7    3   9.0   5.0   29.4  84.9    -1.6    202  1.0
  8000   18.7  65.7   245    5    3   9.1   5.0   29.4  84.8    -1.7    175  0.9
  7750   19.4  66.9   230    5    3   8.8   4.8   29.3  84.7    -1.8    147  0.7
  7500   20.0  68.0   215    6    3  10.1   5.5   29.2  84.6    -1.8    119  0.6
  7250   20.7  69.3   200    7    3   5.3   2.9   29.2  84.5    -1.9     92  0.5
  7000   20.7  69.3   190    8    4  -4.8  -2.6   28.4  83.1    -2.6     85  0.4
  6750   20.2  68.4   175    7    4  -6.8  -3.8   27.2  80.9    -3.9     93  0.5
  6500   19.9  67.8   155    6    3   0.7   0.4   26.1  79.0    -4.9     95  0.5
  6250   20.2  68.4   135    6    3   5.0   2.8   25.7  78.2    -5.4     79  0.4
  6000   20.5  68.9   115    8    4   3.8   2.1   25.3  77.5    -5.8     63  0.3
  5750   20.8  69.4   110    7    4   4.5   2.5   24.8  76.7    -6.3     47  0.2
  5500   21.0  69.8   110    7    3   2.9   1.6   24.4  75.9    -6.7     31  0.2
  5250   20.8  69.4   110    6    3 -12.9  -7.1   23.4  74.2    -7.7     30  0.2
  5000   18.9  66.0   110    5    3 -37.7 -20.7   20.8  69.4   -10.4     80  0.4

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

           09/26/2014 at 0900 MDT          |       09/26/2014 at 1200 MDT
                                           |
K index... +25.7  LI... +1.9               | K index... +26.5  LI... +2.3
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... -6.1
                                           |
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 -67.3 -89.1  220  20 10   2.5   1.4 | -67.9 -90.2  215  23 12   2.7   1.5
 45000 -61.8 -79.2  230  18  9   6.5   3.6 | -62.2 -80.0  225  21 11   6.5   3.5
 40000 -51.5 -60.7  245  18  9   6.2   3.4 | -52.1 -61.8  245  20 10   6.4   3.5
 38000 -47.8 -54.0  225  16  8   6.2   3.4 | -48.3 -54.9  230  19 10   6.4   3.5
 36000 -44.1 -47.4  200  16  8   6.2   3.4 | -44.4 -47.9  215  19 10   6.4   3.5
 34000 -39.7 -39.5  195  16  8   7.4   4.1 | -39.9 -39.8  200  19 10   7.6   4.2
 32000 -35.3 -31.5  190  17  9   7.3   4.0 | -35.4 -31.7  190  19 10   7.5   4.1
 30000 -30.7 -23.3  195  16  8   7.8   4.3 | -30.7 -23.3  185  17  9   7.9   4.3
 29000 -28.4 -19.1  200  15  8   7.8   4.3 | -28.3 -18.9  185  16  8   7.9   4.3
 28000 -26.1 -15.0  205  15  8   7.7   4.2 | -26.0 -14.8  185  16  8   7.8   4.3
 27000 -23.2  -9.8  200  15  8   7.6   4.2 | -23.1  -9.6  185  17  9   7.6   4.2
 26000 -20.9  -5.6  195  15  8   7.6   4.2 | -20.8  -5.4  185  18  9   7.7   4.2
 25000 -18.7  -1.7  195  15  8   7.7   4.2 | -18.5  -1.3  185  19 10   7.6   4.2
 24000 -16.3   2.7  190  15  8   8.0   4.4 | -16.3   2.7  185  20 10   7.6   4.2
 23000 -13.9   7.0  190  15  8   8.0   4.4 | -14.0   6.8  180  21 11   7.6   4.2
 22000 -11.6  11.1  185  15  8   7.0   3.9 | -11.7  10.9  180  22 11   6.9   3.8
 21000  -9.8  14.4  190  15  8   5.9   3.2 | -10.0  14.0  185  20 10   6.1   3.3
 20000  -8.1  17.4  195  15  8   5.9   3.2 |  -8.2  17.2  190  19 10   6.2   3.4
 19500  -7.3  18.9  200  15  7   6.1   3.3 |  -7.3  18.9  195  18  9   6.4   3.5
 19000  -6.5  20.3  205  14  7   4.4   2.4 |  -6.6  20.1  200  18  9   4.3   2.4
 18500  -5.8  21.6  205  14  7   4.7   2.6 |  -5.9  21.4  205  17  9   4.5   2.5
 18000  -5.2  22.6  210  14  7   5.2   2.9 |  -5.3  22.5  215  16  8   4.7   2.6
 17500  -4.4  24.1  215  14  7   5.9   3.2 |  -4.7  23.5  220  15  8   4.9   2.7
 17000  -3.6  25.5  220  14  7   5.9   3.2 |  -4.1  24.6  225  15  7   5.0   2.7
 16500  -2.7  27.1  220  14  7   6.9   3.8 |  -3.2  26.2  225  14  7   8.0   4.4
 16000  -1.8  28.8  220  14  7   6.9   3.8 |  -2.1  28.2  230  14  7   7.8   4.3
 15500  -0.8  30.6  220  14  7   7.7   4.2 |  -1.0  30.2  230  14  7   8.3   4.6
 15000   0.3  32.5  225  14  7   8.0   4.4 |   0.2  32.4  230  14  7   8.5   4.7
 14500   1.4  34.5  225  13  7   8.2   4.5 |   1.4  34.5  230  14  7   8.4   4.6
 14000   2.7  36.9  230  13  7   8.6   4.7 |   2.7  36.9  235  15  8   8.1   4.5
 13500   4.6  40.3  235  13  7   8.5   4.7 |   3.9  39.0  240  15  8   8.1   4.4
 13000   5.9  42.6  240  13  7   8.5   4.7 |   5.7  42.3  245  16  8   7.7   4.2
 12500   7.2  45.0  245  13  7   8.4   4.6 |   6.8  44.2  245  16  8   7.8   4.3
 12000   8.4  47.1  245  13  7   8.2   4.5 |   8.0  46.4  245  16  8   7.9   4.3
 11500   9.6  49.3  245  13  7   8.1   4.4 |   9.2  48.6  245  15  8   8.2   4.5
 11000  10.8  51.4  245  12  6   7.7   4.2 |  10.4  50.7  245  14  7   8.2   4.5
 10500  12.0  53.6  250  11  6   4.3   2.4 |  11.7  53.1  245  13  7   4.5   2.4
 10250  12.2  54.0  250  10  5   4.7   2.6 |  11.9  53.4  245  12  6   5.0   2.8
 10000  12.8  55.0  250  10  5   9.5   5.2 |  12.6  54.7  250  12  6  10.4   5.7
  9750  13.4  56.1  250  10  5   8.7   4.7 |  13.3  55.9  250  11  6   9.5   5.2
  9500  14.1  57.4  250   9  5   7.3   4.0 |  13.9  57.0  255  11  6   7.7   4.2
  9250  14.5  58.1  250   9  5   6.0   3.3 |  14.4  57.9  255  10  5   6.1   3.3
  9000  15.0  59.0  255   8  4   7.3   4.0 |  14.9  58.8  255  10  5   7.5   4.1
  8750  15.6  60.1  255   8  4   7.5   4.1 |  15.5  59.9  260   9  5   7.5   4.1
  8500  16.1  61.0  255   7  4   7.0   3.8 |  16.0  60.8  260   9  4   7.1   3.9
  8250  16.6  61.9  250   6  3   6.5   3.6 |  16.5  61.7  260   7  4   6.8   3.7
  8000  17.1  62.8  250   6  3   6.6   3.6 |  17.0  62.6  260   6  3   6.2   3.4
  7750  17.6  63.7  240   5  3   6.3   3.5 |  17.4  63.3  265   5  2   6.0   3.3
  7500  18.0  64.4  225   5  2   5.2   2.8 |  17.9  64.2  265   4  2   7.8   4.3
  7250  18.4  65.1  210   5  3   4.5   2.5 |  18.5  65.3  265   4  2   8.4   4.6
  7000  18.7  65.7  200   6  3   4.7   2.6 |  19.1  66.4  265   3  2   9.0   4.9
  6750  19.0  66.2  190   6  3   2.2   1.2 |  19.9  67.8  265   3  2  10.5   5.7
  6500  19.0  66.2  180   6  3  -0.7  -0.4 |  20.7  69.3  270   3  2  10.8   5.9
  6250  19.0  66.2  170   6  3  -1.0  -0.5 |  21.5  70.7  270   3  2  11.1   6.1
  6000  18.9  66.0  160   6  3  -0.8  -0.4 |  22.3  72.1  270   3  2  10.2   5.6
  5750  18.9  66.0  140   5  3   0.8   0.4 |  23.0  73.4  270   3  2  11.4   6.3
  5500  18.9  66.0  135   5  2   2.2   1.2 |  24.0  75.2  270   3  2  13.5   7.4
  5250  19.0  66.2  125   4  2   1.2   0.7 |  24.9  76.8  270   3  2  11.8   6.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/26/2014 at 1500 MDT          |       09/26/2014 at 1800 MDT
                                           |
K index... +28.1  LI... +1.1               | K index... +29.1  LI... +0.4
CAPE... 0.0  CIN... -24.6                  | CAPE... +100.9  CIN... -21.4
                                           |
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 -67.8 -90.0  215  27 14   3.0   1.6 | -68.0 -90.4  225  28 15   2.4   1.3
 45000 -61.8 -79.2  230  24 12   6.5   3.5 | -62.3 -80.1  235  25 13   7.1   3.9
 40000 -51.8 -61.2  240  22 11   5.9   3.2 | -51.9 -61.4  235  23 12   5.8   3.2
 38000 -48.2 -54.8  230  20 11   5.9   3.2 | -48.4 -55.1  225  22 11   5.8   3.2
 36000 -44.7 -48.5  220  20 10   5.8   3.2 | -44.9 -48.8  215  22 11   5.7   3.1
 34000 -40.3 -40.5  210  20 10   7.5   4.1 | -40.8 -41.4  210  22 11   7.1   3.9
 32000 -35.8 -32.4  205  20 10   7.4   4.1 | -36.0 -32.8  205  21 11   6.9   3.8
 30000 -31.0 -23.8  195  19 10   8.1   4.5 | -31.1 -24.0  205  20 10   8.2   4.5
 29000 -28.6 -19.5  190  18  9   8.1   4.5 | -28.7 -19.7  200  19 10   8.2   4.5
 28000 -26.2 -15.2  190  17  9   7.9   4.4 | -26.2 -15.2  195  18  9   7.7   4.2
 27000 -23.3  -9.9  185  19 10   7.6   4.2 | -24.0 -11.2  195  19 10   7.5   4.1
 26000 -21.0  -5.8  185  20 10   7.6   4.2 | -21.7  -7.1  195  19 10   7.5   4.1
 25000 -18.7  -1.7  185  20 11   7.7   4.2 | -19.5  -3.1  195  20 10   7.5   4.1
 24000 -16.4   2.5  185  22 11   7.7   4.2 | -17.1   1.2  195  21 11   7.9   4.3
 23000 -14.1   6.6  185  24 12   7.7   4.2 | -14.8   5.4  200  22 11   7.9   4.3
 22000 -11.8  10.8  185  26 13   7.3   4.0 | -12.4   9.7  200  23 12   7.7   4.2
 21000  -9.8  14.4  190  24 13   6.8   3.7 | -10.3  13.5  205  22 11   6.9   3.8
 20000  -7.8  18.0  195  23 12   6.8   3.7 |  -8.3  17.1  210  22 11   7.0   3.8
 19500  -6.8  19.8  195  23 12   7.2   3.9 |  -7.2  19.0  215  21 11   7.3   4.0
 19000  -6.1  21.0  200  22 11   3.7   2.0 |  -6.4  20.5  215  21 11   3.6   2.0
 18500  -5.5  22.1  205  20 10   4.4   2.4 |  -6.0  21.2  220  19 10   3.6   2.0
 18000  -5.0  23.0  210  19 10   5.1   2.8 |  -5.5  22.1  225  17  9   4.6   2.5
 17500  -4.2  24.4  215  17  9   5.6   3.1 |  -4.7  23.5  225  16  8   7.1   3.9
 17000  -3.4  25.9  215  16  8   5.6   3.0 |  -3.7  25.3  230  15  8   7.1   3.9
 16500  -2.6  27.3  220  15  8   6.6   3.6 |  -2.7  27.1  230  14  7   7.5   4.1
 16000  -1.8  28.8  220  15  8   6.6   3.6 |  -1.7  28.9  230  13  7   7.7   4.2
 15500  -0.9  30.4  225  15  8   8.0   4.4 |  -0.7  30.7  230  12  6   8.5   4.6
 15000   0.4  32.7  225  14  7   8.6   4.7 |   1.3  34.3  230  11  5   9.2   5.0
 14500   1.6  34.9  230  14  7   8.5   4.7 |   2.6  36.7  225  10  5   8.1   4.5
 14000   2.8  37.0  230  14  7   8.3   4.6 |   3.7  38.7  225   9  5   7.9   4.3
 13500   4.1  39.4  230  13  7   8.3   4.6 |   4.9  40.8  225   8  4   8.4   4.6
 13000   5.9  42.6  235  12  6   8.0   4.4 |   6.2  43.2  225   8  4   8.8   4.9
 12500   7.1  44.8  235  12  6   8.4   4.6 |   7.6  45.7  225   7  4   8.8   4.8
 12000   8.4  47.1  240  12  6   8.9   4.9 |   8.9  48.0  225   6  3   8.7   4.8
 11500   9.7  49.5  245  12  6   8.7   4.8 |  10.2  50.4  225   6  3   8.7   4.7
 11000  11.0  51.8  245  11  6   8.1   4.5 |  11.5  52.7  230   5  3   8.3   4.5
 10500  12.2  54.0  250  10  5   4.5   2.5 |  12.7  54.9  240   5  3   5.6   3.1
 10250  12.4  54.3  250  10  5   5.3   2.9 |  13.1  55.6  240   5  3   6.1   3.3
 10000  13.1  55.6  250   9  5  10.6   5.8 |  13.7  56.7  245   5  2   9.9   5.4
  9750  13.8  56.8  255   9  5   9.8   5.4 |  14.4  57.9  250   5  2   9.1   5.0
  9500  14.5  58.1  255   8  4   7.5   4.1 |  15.1  59.2  255   5  2   8.5   4.7
  9250  15.0  59.0  260   8  4   6.1   3.4 |  15.7  60.3  260   5  2   7.5   4.1
  9000  15.6  60.1  265   7  4   8.2   4.5 |  16.3  61.3  265   4  2   7.8   4.3
  8750  16.2  61.2  270   7  3   8.4   4.6 |  16.9  62.4  270   4  2   7.9   4.4
  8500  16.8  62.2  280   6  3   7.4   4.1 |  17.5  63.5  275   4  2   7.8   4.3
  8250  17.3  63.1  285   6  3   6.4   3.5 |  18.1  64.6  280   4  2   7.6   4.1
  8000  17.8  64.0  290   6  3   7.8   4.3 |  18.6  65.5  290   4  2   7.2   4.0
  7750  18.4  65.1  295   6  3   8.6   4.7 |  19.2  66.6  305   3  2   7.0   3.8
  7500  19.0  66.2  295   6  3   9.8   5.4 |  19.7  67.5  315   3  1   7.1   3.9
  7250  19.8  67.6  295   6  3  10.9   6.0 |  20.2  68.4  320   3  1   6.9   3.8
  7000  20.6  69.1  295   6  3  10.2   5.6 |  20.7  69.3  325   2  1   7.8   4.3
  6750  21.3  70.3  295   6  3  10.1   5.5 |  21.3  70.3  325   2  1   9.3   5.1
  6500  22.1  71.8  295   6  3  10.4   5.7 |  22.0  71.6  325   2  1   9.6   5.3
  6250  22.9  73.2  295   5  3  10.9   6.0 |  22.8  73.0  325   2  1   9.8   5.4
  6000  23.7  74.7  295   5  3   9.5   5.2 |  23.5  74.3  320   2  1   9.8   5.4
  5750  24.4  75.9  295   5  3  11.3   6.2 |  24.2  75.6  320   2  1   8.7   4.8
  5500  25.4  77.7  295   6  3  14.8   8.1 |  24.8  76.6  320   2  1   7.5   4.1
  5250  26.4  79.5  295   6  3  12.1   6.6 |  25.3  77.5  320   2  1   8.0   4.4
  5000     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 at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 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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