Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 091230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0630 MDT Wednesday, July 9, 2014

This forecast is for Wednesday, July 9, 2014:

If the trigger temperature of 82.1 F/27.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 517 ft/min (2.6 m/s)
   Maximum height of thermals.................. 13814 ft MSL (8975 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
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................. 11987 ft MSL (7148 ft AGL)
Thermal soaring outlook for Thursday 07/10..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:56:30 / 20:42:19 MDT
Total possible sunshine........... 14 hr 45 min 49 sec (885 min 49 sec)
Altitude of sun at 13:19:23 MDT... 73.14 degrees

Upper air data from rawinsonde observation taken on 07/09/2014 at 0600 MDT

Freezing level.................. 16238 ft MSL (11399 ft AGL)
Convective condensation level... 15908 ft MSL (11069 ft AGL)
Lifted condensation level....... 15521 ft MSL (10682 ft AGL)
Lifted index.................... -2.1
K index......................... +24.8

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  -68.5 -91.3   355   22   11   5.1   2.8   79.7 175.4    27.2      M    M
 45000  -59.9 -75.8   340   25   13   5.8   3.2   69.3 156.7    22.7      M    M
 40000  -51.4 -60.5   305   29   15  -2.4  -1.3   58.9 138.0    17.5      M    M
 38000  -49.3 -56.7   285   32   16   7.5   4.1   53.4 128.2    14.2      M    M
 36000  -44.5 -48.1   275   26   13   8.2   4.5   52.0 125.6    13.5      M    M
 34000  -39.4 -38.9   275   23   12   9.1   5.0   50.9 123.6    13.1      M    M
 32000  -34.0 -29.2   275   19   10   9.2   5.1   50.4 122.7    13.0      M    M
 30000  -28.4 -19.1   275   19   10   8.3   4.6   49.2 120.5    12.4      M    M
 29000  -26.0 -14.8   290   19   10   7.3   4.0   48.5 119.2    11.9      M    M
 28000  -24.4 -11.9   285   18    9   9.8   5.4   46.7 116.1    10.7      M    M
 27000  -22.0  -7.6   285   18    9   5.8   3.2   46.2 115.1    10.4      M    M
 26000  -20.0  -4.0   320   12    6   6.9   3.8   45.0 113.0     9.6      M    M
 25000  -17.8  -0.0   310   11    6   7.6   4.2   44.1 111.3     8.9      M    M
 24000  -15.8   3.6   310    9    5   2.8   1.5   43.0 109.4     8.1      M    M
 23000  -14.5   5.9   315    7    4   1.1   0.6   41.1 106.0     6.6      M    M
 22000  -12.4   9.7   315    5    3   7.8   4.3   40.1 104.1     5.9      M    M
 21000  -11.1  12.0   325    4    2  10.4   5.7   38.4 101.0     4.3      M    M
 20000   -9.2  15.4   345    2    1   4.6   2.6   37.2  99.0     3.3      M    M
 19500   -7.9  17.8   330    3    1   8.8   4.8   36.9  98.5     3.2      M    M
 19000   -6.6  20.1   335    3    1   9.1   5.0   36.8  98.3     3.1      M    M
 18500   -5.4  22.3   350    3    2   8.0   4.4   36.5  97.7     2.8      M    M
 18000   -4.2  24.4   360    3    2   7.9   4.3   36.2  97.1     2.6      M    M
 17500   -3.1  26.4   010    3    2   7.8   4.3   35.8  96.5     2.2      M    M
 17000   -2.0  28.4   020    4    2   7.9   4.3   35.5  95.9     1.9      M    M
 16500   -0.3  31.5   030    5    2   7.9   4.3   35.1  95.1     1.4      M    M
 16000    0.9  33.6   030    5    2   8.8   4.8   34.8  94.7     1.1      M    M
 15500    2.2  36.0   010    3    1   8.9   4.9   34.7  94.4     0.9      M    M
 15000    3.5  38.3   320    2    1   8.9   4.9   34.5  94.1     0.8      M    M
 14500    4.8  40.6   285    3    2   9.2   5.0   34.4  93.9     0.7      M    M
 14000    5.8  42.4   265    5    3   3.6   2.0   34.0  93.3     0.3      M    M
 13500    6.0  42.8   250    8    4   3.6   2.0   32.8  91.0    -1.0    702  3.6
 13000    6.8  44.2   245   10    5   6.0   3.3   32.1  89.8    -1.6    662  3.4
 12500    7.7  45.9   250   14    7   5.3   2.9   31.5  88.6    -2.2    621  3.2
 12000    8.3  46.9   250   18    9   5.0   2.7   30.7  87.3    -3.0    587  3.0
 11500    9.3  48.7   250   17    9   8.1   4.4   30.2  86.4    -3.6    545  2.8
 11000   10.4  50.7   255   17    9   7.8   4.3   29.9  85.8    -3.9    496  2.5
 10500   11.6  52.9   255   16    8   8.3   4.5   29.6  85.3    -4.2    446  2.3
 10250   12.2  54.0   255   15    8   8.9   4.9   29.5  85.1    -4.3    420  2.1
 10000   12.9  55.2   260   15    8   8.8   4.8   29.4  85.0    -4.4    393  2.0
  9750   13.5  56.3   260   14    7   8.8   4.8   29.4  84.9    -4.5    366  1.9
  9500   14.2  57.6   265   13    7   8.8   4.8   29.3  84.7    -4.6    338  1.7
  9250   14.8  58.6   265   13    7   8.8   4.9   29.2  84.6    -4.6    311  1.6
  9000   15.5  59.9   270   12    6   8.8   4.8   29.2  84.5    -4.7    284  1.4
  8750   16.1  61.0   275   11    6   9.1   5.0   29.1  84.4    -4.8    257  1.3
  8500   16.8  62.2   280   11    6   8.0   4.4   29.0  84.2    -4.9    230  1.2
  8250   17.3  63.1   285   10    5   6.9   3.8   28.8  83.9    -5.1    207  1.1
  8000   17.8  64.0   295   10    5   7.1   3.9   28.6  83.5    -5.3    185  0.9
  7750   18.3  64.9   295    8    4   7.1   3.9   28.4  83.2    -5.5    162  0.8
  7500   18.9  66.0   300    6    3   7.1   3.9   28.2  82.8    -5.7    139  0.7
  7250   19.4  66.9   305    4    2   7.1   3.9   28.0  82.4    -6.0    116  0.6
  7000   19.9  67.8   325    2    1   7.1   3.9   27.8  82.1    -6.2     93  0.5
  6750   20.4  68.7   000    0    0   7.1   3.9   27.6  81.7    -6.4     70  0.4
  6500   20.9  69.6   135    3    2   7.1   3.9   27.4  81.4    -6.6     47  0.2
  6250   21.5  70.7   140    6    3   7.1   3.9   27.2  81.0    -6.9     24  0.1
  6000   22.0  71.6   140    9    5   7.1   3.9   27.0  80.6    -7.1      1  0.0
  5750   22.5  72.5   135    9    5   7.1   3.9   26.8  80.3    -7.3      M    M
  5500   23.0  73.4   125    9    5   7.1   3.9   26.6  79.9    -7.5      M    M
  5250   23.5  74.3   120    8    4   7.1   3.9   26.4  79.5    -7.8      M    M
  5000   24.0  75.2   110    8    4   7.2   4.0   26.2  79.2    -8.0      M    M

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

           07/09/2014 at 0900 MDT          |       07/09/2014 at 1200 MDT
                                           |
K index... +29.3  LI... -1.9               | K index... +28.8  LI... -2.2
CAPE... +311.7  CIN... -140.0              | CAPE... +430.1  CIN... -12.6
                                           |
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  360  19 10   3.5   1.9 | -66.2 -87.2  005  17  9   3.0   1.7
 45000 -58.7 -73.7  350  28 14   5.7   3.1 | -59.6 -75.3  355  25 13   6.3   3.4
 40000 -50.3 -58.5  330  28 14   5.2   2.9 | -50.3 -58.5  335  23 12   5.7   3.1
 38000 -47.1 -52.8  310  25 13   5.2   2.9 | -46.9 -52.4  305  21 11   5.7   3.1
 36000 -44.0 -47.2  290  25 13   6.0   3.3 | -43.4 -46.1  280  25 13   6.6   3.6
 34000 -39.2 -38.6  290  22 11   8.2   4.5 | -38.5 -37.3  280  22 12   8.4   4.6
 32000 -34.2 -29.6  285  19 10   8.0   4.4 | -33.4 -28.1  280  19 10   9.2   5.0
 30000 -28.7 -19.7  285  16  8   8.3   4.6 | -28.1 -18.6  280  16  8   7.9   4.3
 29000 -26.2 -15.2  285  16  8   8.3   4.6 | -25.8 -14.4  280  15  8   7.9   4.3
 28000 -23.9 -11.0  285  14  7   6.5   3.6 | -23.5 -10.3  280  14  7   7.0   3.9
 27000 -21.9  -7.4  290  13  7   6.7   3.7 | -21.4  -6.5  285  13  7   7.1   3.9
 26000 -20.0  -4.0  290  11  6   6.7   3.7 | -19.3  -2.7  290  12  6   7.1   3.9
 25000 -18.0  -0.4  295  10  5   5.9   3.2 | -17.2   1.0  295  11  6   6.6   3.6
 24000 -16.4   2.5  295   7  4   5.3   2.9 | -15.4   4.3  300   8  4   6.3   3.4
 23000 -14.9   5.2  295   4  2   5.3   2.9 | -13.5   7.7  310   5  2   6.3   3.4
 22000 -13.2   8.2  295   1  1   7.3   4.0 | -11.6  11.1  350   3  1   6.6   3.6
 21000 -10.8  12.6  170   2  1   8.2   4.5 |  -9.6  14.7  125   1  1   6.8   3.8
 20000  -8.4  16.9  155   5  3   8.2   4.5 |  -7.6  18.3  150   5  2   6.9   3.8
 19500  -7.2  19.0  155   6  3   8.0   4.4 |  -6.6  20.1  150   7  3   6.8   3.7
 19000  -6.1  21.0  150   7  3   6.8   3.7 |  -5.6  21.9  150   7  4   6.2   3.4
 18500  -5.1  22.8  150   6  3   6.8   3.7 |  -4.7  23.5  145   7  4   6.3   3.4
 18000  -4.1  24.6  145   6  3   7.7   4.3 |  -3.8  25.2  140   7  4   6.4   3.5
 17500  -3.8  25.2  140   5  3   8.1   4.4 |  -2.9  26.8  135   6  3   6.6   3.6
 17000  -1.8  28.8  135   5  2   8.0   4.4 |  -2.0  28.4  125   6  3   6.6   3.6
 16500  -0.7  30.7  135   4  2   7.4   4.1 |  -1.0  30.2  120   6  3   6.7   3.7
 16000   0.4  32.7  140   4  2   7.5   4.1 |  -0.0  32.0  115   6  3   6.7   3.7
 15500   1.4  34.5  145   3  2   6.8   3.7 |   0.9  33.6  110   5  3   6.8   3.8
 15000   2.4  36.3  155   2  1   6.8   3.7 |   1.9  35.4  110   4  2   6.9   3.8
 14500   3.9  39.0  205   1  1   8.2   4.5 |   3.4  38.1  105   3  2   7.5   4.1
 14000   5.1  41.2  255   3  1   8.1   4.4 |   4.5  40.1  115   2  1   7.5   4.1
 13500   6.2  43.2  265   4  2   7.9   4.3 |   5.5  41.9  160   1  1   6.8   3.7
 13000   7.4  45.3  265   5  3   7.9   4.3 |   6.5  43.7  190   3  1   6.6   3.6
 12500   8.5  47.3  260   7  3   7.6   4.2 |   7.5  45.5  195   4  2   8.5   4.7
 12000   9.7  49.5  250   6  3   7.6   4.1 |   8.8  47.8  195   6  3   9.3   5.1
 11500  10.8  51.4  240   7  3   7.7   4.2 |  10.2  50.4  195   7  4   9.2   5.0
 11000  11.9  53.4  225   6  3   7.8   4.3 |  11.5  52.7  200   7  4   8.9   4.9
 10500  13.0  55.4  205   7  3   4.5   2.5 |  12.7  54.9  205   8  4   5.2   2.8
 10250  13.3  55.9  205   7  3   6.9   3.8 |  13.0  55.4  210   8  4   6.6   3.6
 10000  14.0  57.2  205   7  3  10.9   6.0 |  13.8  56.8  215   8  4  11.0   6.0
  9750  14.8  58.6  210   7  3   9.9   5.4 |  14.5  58.1  220   8  4  10.2   5.6
  9500  15.4  59.7  210   7  3   7.9   4.3 |  15.2  59.4  220   8  4   7.5   4.1
  9250  15.9  60.6  220   7  3   7.2   4.0 |  15.6  60.1  225   7  4   6.7   3.7
  9000  16.6  61.9  230   7  4   9.3   5.1 |  16.2  61.2  225   7  4   9.1   5.0
  8750  17.2  63.0  235   7  4   9.0   4.9 |  16.8  62.2  225   7  3   9.0   4.9
  8500  17.8  64.0  245   8  4   7.1   3.9 |  17.5  63.5  225   7  3   9.7   5.3
  8250  18.2  64.8  245   7  4   6.0   3.3 |  18.2  64.8  225   7  3  10.1   5.5
  8000  18.7  65.7  245   7  3   6.5   3.6 |  18.9  66.0  220   7  3   9.7   5.3
  7750  19.1  66.4  245   6  3   5.9   3.2 |  19.7  67.5  220   7  3   9.7   5.3
  7500  19.5  67.1  235   5  3   4.7   2.6 |  20.4  68.7  225   7  3  10.1   5.5
  7250  19.8  67.6  215   5  3   4.4   2.4 |  21.2  70.2  225   7  3  10.2   5.6
  7000  20.1  68.2  200   6  3   4.5   2.4 |  21.9  71.4  225   6  3   9.9   5.5
  6750  20.4  68.7  185   7  4   5.6   3.1 |  22.7  72.9  225   6  3  10.4   5.7
  6500  20.9  69.6  180   7  4   6.5   3.6 |  23.5  74.3  225   6  3  11.1   6.1
  6250  21.3  70.3  175   6  3   6.4   3.5 |  24.3  75.7  225   6  3  11.2   6.1
  6000  21.7  71.1  170   6  3   6.4   3.5 |  25.1  77.2  225   6  3  10.7   5.9
  5750  22.2  72.0  165   5  3   9.1   5.0 |  25.9  78.6  225   6  3  13.2   7.3
  5500  23.0  73.4  165   5  3  11.7   6.4 |  27.1  80.8  225   6  3  16.1   8.8
  5250  23.8  74.8  165   5  3   9.8   5.4 |  28.2  82.8  225   6  3  13.9   7.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/09/2014 at 1500 MDT          |       07/09/2014 at 1800 MDT
                                           |
K index... +25.5  LI... -1.8               | K index... +24.0  LI... -1.7
CAPE... +247.9  CIN... -15.6               | CAPE... +125.1  CIN... -71.1
                                           |
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 -66.0 -86.8  005  17  9   2.9   1.6 | -65.3 -85.5  350  16  8   3.1   1.7
 45000 -59.5 -75.1  355  25 13   6.3   3.4 | -58.9 -74.0  350  21 11   6.1   3.3
 40000 -50.2 -58.4  340  23 12   6.0   3.3 | -49.8 -57.6  340  20 10   6.3   3.4
 38000 -46.6 -51.9  320  19 10   6.0   3.3 | -46.0 -50.8  325  18  9   6.3   3.4
 36000 -43.0 -45.4  295  19 10   6.9   3.8 | -42.2 -44.0  310  16  8   6.7   3.7
 34000 -37.9 -36.2  285  17  9   8.6   4.7 | -37.5 -35.5  300  15  8   7.8   4.3
 32000 -32.1 -25.8  275  16  8   8.9   4.9 | -32.2 -26.0  280  15  8   8.6   4.7
 30000 -27.6 -17.7  280  13  7   7.6   4.2 | -27.6 -17.7  280  12  6   7.8   4.3
 29000 -25.4 -13.7  285  12  6   7.6   4.2 | -25.3 -13.5  280  10  5   7.8   4.3
 28000 -23.2  -9.8  290  10  5   7.0   3.8 | -23.1  -9.6  285   8  4   6.9   3.8
 27000 -21.1  -6.0  290   9  5   7.1   3.9 | -21.0  -5.8  295   6  3   7.0   3.8
 26000 -19.0  -2.2  295   7  4   7.1   3.9 | -18.9  -2.0  320   4  2   7.0   3.8
 25000 -16.9   1.6  305   6  3   6.5   3.6 | -16.9   1.6  350   4  2   6.6   3.6
 24000 -15.1   4.8  305   4  2   6.1   3.3 | -15.1   4.8  020   4  2   6.1   3.4
 23000 -13.4   7.9  310   2  1   6.1   3.3 | -13.3   8.1  045   5  2   6.1   3.4
 22000 -11.6  11.1  100   1  0   6.5   3.6 | -11.5  11.3  060   6  3   6.4   3.5
 21000  -9.6  14.7  170   4  2   6.8   3.7 |  -9.5  14.9  075   5  3   6.5   3.6
 20000  -7.5  18.5  170   9  4   6.8   3.7 |  -7.6  18.3  090   5  3   6.6   3.6
 19500  -6.5  20.3  175  11  6   6.7   3.7 |  -6.6  20.1  095   5  2   6.6   3.6
 19000  -5.6  21.9  175  12  6   6.3   3.5 |  -5.6  21.9  110   5  2   7.5   4.1
 18500  -4.7  23.5  170  12  6   6.4   3.5 |  -4.5  23.9  125   5  2   7.4   4.1
 18000  -3.7  25.3  170  12  6   6.3   3.5 |  -3.4  25.9  135   5  3   7.5   4.1
 17500  -2.8  27.0  165  12  6   6.3   3.5 |  -2.3  27.9  140   6  3   7.6   4.2
 17000  -1.9  28.6  160  11  6   6.3   3.5 |  -1.1  30.0  145   7  4   7.6   4.2
 16500  -0.9  30.4  155  11  6   6.6   3.6 |  -0.1  31.8  150   8  4   6.9   3.8
 16000   0.1  32.2  155  11  5   6.6   3.6 |   1.0  33.8  155   9  5   7.0   3.8
 15500   1.0  33.8  150  10  5   6.9   3.8 |   2.5  36.5  160  10  5   7.2   4.0
 15000   2.5  36.5  145  10  5   6.9   3.8 |   3.6  38.5  160  11  6   7.2   4.0
 14500   3.5  38.3  145   9  5   6.9   3.8 |   4.7  40.5  165  12  6   7.1   3.9
 14000   4.5  40.1  140   8  4   7.0   3.8 |   5.7  42.3  165  12  6   7.1   3.9
 13500   5.5  41.9  140   7  4   6.3   3.4 |   6.7  44.1  170  12  6   7.1   3.9
 13000   6.3  43.3  150   6  3   6.2   3.4 |   7.8  46.0  175  13  7   7.2   3.9
 12500   7.2  45.0  160   5  3   7.2   4.0 |   8.8  47.8  180  13  7   6.8   3.7
 12000   8.3  46.9  175   5  3   7.7   4.2 |   9.7  49.5  185  13  7   6.5   3.6
 11500   9.4  48.9  190   5  3   8.8   4.8 |  10.6  51.1  190  12  6   6.9   3.8
 11000  10.8  51.4  195   5  3   9.4   5.2 |  11.6  52.9  195  12  6   7.2   4.0
 10500  12.1  53.8  205   5  3   5.7   3.1 |  12.7  54.9  200  11  6   4.6   2.5
 10250  12.5  54.5  205   5  3   7.5   4.1 |  12.9  55.2  200  11  6   6.3   3.5
 10000  13.3  55.9  210   5  3  12.2   6.7 |  13.6  56.5  205  11  6  11.0   6.1
  9750  14.1  57.4  210   5  3  11.2   6.1 |  14.3  57.7  205  10  5  10.2   5.6
  9500  14.9  58.8  210   6  3   9.0   4.9 |  15.1  59.2  205  10  5   8.9   4.9
  9250  15.5  59.9  210   6  3   8.2   4.5 |  15.6  60.1  205  10  5   8.1   4.5
  9000  16.2  61.2  210   6  3  10.4   5.7 |  16.3  61.3  205  10  5   9.6   5.3
  8750  16.9  62.4  210   6  3  10.2   5.6 |  17.0  62.6  200   9  5   9.6   5.2
  8500  17.6  63.7  210   6  3   9.8   5.4 |  17.7  63.9  200   9  5   9.1   5.0
  8250  18.3  64.9  215   6  3   9.6   5.3 |  18.3  64.9  200   9  5   8.8   4.8
  8000  19.0  66.2  215   6  3   9.9   5.4 |  19.0  66.2  195   9  4   8.9   4.9
  7750  19.7  67.5  215   6  3   9.9   5.4 |  19.6  67.3  195   9  4   9.1   5.0
  7500  20.4  68.7  215   6  3   9.7   5.3 |  20.3  68.5  195   8  4   9.9   5.4
  7250  21.1  70.0  215   6  3   9.6   5.3 |  21.1  70.0  195   8  4  10.6   5.8
  7000  21.9  71.4  215   6  3   9.8   5.4 |  21.9  71.4  195   8  4   9.8   5.4
  6750  22.6  72.7  215   6  3  10.2   5.6 |  22.6  72.7  195   8  4   9.9   5.4
  6500  23.4  74.1  215   6  3  10.4   5.7 |  23.3  73.9  195   8  4  10.8   5.9
  6250  24.1  75.4  215   6  3  10.5   5.7 |  24.1  75.4  195   8  4  11.4   6.3
  6000  24.9  76.8  215   6  3  10.1   5.5 |  25.0  77.0  195   8  4   9.6   5.3
  5750  25.6  78.1  215   6  3   9.4   5.1 |  25.6  78.1  195   8  4   9.8   5.4
  5500  26.3  79.3  220   5  3   9.2   5.1 |  26.5  79.7  195   7  4  12.1   6.6
  5250  27.0  80.6  220   5  3   9.3   5.1 |  27.3  81.1  195   7  4  10.2   5.6
  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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