Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 011230
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0630 MDT Tuesday, September 1, 2015

This forecast is for Tuesday, September 1, 2015:

If the trigger temperature of 80.2 F/26.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1353 ft/min (6.9 m/s)
   Maximum height of thermals.................. 17324 ft MSL (12485 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1145 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................. 10606 ft MSL (5767 ft AGL)
Thermal soaring outlook for Wednesday 09/02.... Good

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

Remarks...

Sunrise/Sunset.................... 06:42:38 / 19:46:22 MDT
Total possible sunshine........... 13 hr 3 min 44 sec (783 min 44 sec)
Altitude of sun at 13:14:04 MDT... 59.06 degrees

Upper air data from rawinsonde observation taken on 09/01/2015 at 0600 MDT

Freezing level.................. 14842 ft MSL (10003 ft AGL)
Convective condensation level... 13917 ft MSL (9078 ft AGL)
Lifted condensation level....... 14653 ft MSL (9813 ft AGL)
Lifted index.................... -3.1
K index......................... +28.9

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  -62.3 -80.1   240   26   14   7.3   4.0   91.9 197.4    35.1      M    M
 45000  -61.1 -78.0   255   51   26   5.2   2.8   68.1 154.6    23.0      M    M
 40000  -53.5 -64.3   250   62   32   6.8   3.7   57.1 134.7    17.3      M    M
 38000  -49.3 -56.7   245   67   34   7.6   4.2   54.9 130.8    16.2      M    M
 36000  -44.7 -48.5   250   60   31   7.6   4.2   53.0 127.4    15.3      M    M
 34000  -40.8 -41.4   255   46   24   6.0   3.3   50.3 122.5    13.8      M    M
 32000  -37.2 -35.0   260   30   15   9.3   5.1   46.2 115.2    11.1      M    M
 30000  -32.5 -26.5   255   20   10   7.3   4.0   44.7 112.4    10.2      M    M
 29000  -30.1 -22.2   250   18    9   8.0   4.4   44.0 111.2     9.8      M    M
 28000  -27.7 -17.9   240   17    9   8.5   4.6   43.3 110.0     9.4      M    M
 27000  -25.7 -14.3   245   16    8   1.9   1.1   42.3 108.1     8.7      M    M
 26000  -23.4 -10.1   250   15    8   8.5   4.6   41.4 106.6     8.1      M    M
 25000  -20.8  -5.4   235   16    8   8.9   4.9   41.0 105.7     7.8      M    M
 24000  -18.5  -1.3   230   18    9   7.6   4.2   40.3 104.6     7.4      M    M
 23000  -16.3   2.7   235   16    8   7.0   3.9   39.5 103.1     6.7      M    M
 22000  -14.2   6.4   245   15    8   7.1   3.9   38.4 101.2     5.9      M    M
 21000  -13.3   8.1   255   14    7   3.1   1.7   36.2  97.1     3.9      M    M
 20000  -11.7  10.9   280   14    7   6.5   3.6   34.8  94.6     2.7      M    M
 19500  -10.7  12.7   280   12    6   6.4   3.5   34.2  93.5     2.2      M    M
 19000   -9.7  14.5   280   11    6   7.9   4.3   33.7  92.7     1.8      M    M
 18500   -8.6  16.5   275   10    5   7.6   4.2   33.4  92.0     1.4      M    M
 18000   -7.5  18.5   265    9    5   6.1   3.3   32.9  91.3     1.1      M    M
 17500   -6.7  19.9   260    9    4   5.7   3.1   32.2  89.9     0.4      M    M
 17000   -5.3  22.5   245    8    4   8.9   4.9   31.4  88.5    -0.4   1112  5.6
 16500   -4.0  24.8   235    8    4   8.7   4.8   31.2  88.2    -0.5   1059  5.4
 16000   -2.8  27.0   230    8    4   8.7   4.8   31.1  87.9    -0.7   1005  5.1
 15500   -1.5  29.3   240    9    5   8.7   4.8   30.9  87.6    -0.9    952  4.8
 15000   -0.2  31.6   245   10    5   8.8   4.8   30.7  87.2    -1.1    899  4.6
 14500    1.1  34.0   250   12    6   8.9   4.9   30.5  87.0    -1.3    846  4.3
 14000    2.3  36.1   255   13    7   8.0   4.4   30.3  86.6    -1.5    796  4.0
 13500    3.2  37.8   245   13    7   7.4   4.0   29.8  85.7    -2.0    751  3.8
 13000    4.5  40.1   235   14    7   8.9   4.9   29.7  85.5    -2.2    699  3.5
 12500    5.8  42.4   235   15    7   9.0   5.0   29.6  85.3    -2.4    644  3.3
 12000    7.1  44.8   235   15    8   9.1   5.0   29.5  85.1    -2.5    590  3.0
 11500    8.5  47.3   230   14    7   9.1   5.0   29.4  84.9    -2.7    536  2.7
 11000    9.8  49.6   230   14    7   9.3   5.1   29.3  84.7    -2.8    482  2.4
 10500   11.0  51.8   240   13    7   7.0   3.8   29.0  84.2    -3.1    431  2.2
 10250   11.5  52.7   250   13    7   7.4   4.1   28.8  83.9    -3.3    408  2.1
 10000   12.0  53.6   255   13    7   7.4   4.1   28.6  83.6    -3.5    386  2.0
  9750   12.5  54.5   255   13    7   7.3   4.0   28.5  83.2    -3.8    363  1.8
  9500   13.0  55.4   255   13    7   8.1   4.4   28.3  82.9    -4.0    341  1.7
  9250   13.7  56.7   255   13    7   8.8   4.8   28.2  82.8    -4.1    313  1.6
  9000   14.4  57.9   255   13    7   8.8   4.8   28.1  82.6    -4.1    285  1.4
  8750   15.0  59.0   255   11    6   8.0   4.4   28.0  82.5    -4.2    258  1.3
  8500   15.6  60.1   255   10    5   6.7   3.7   27.8  82.1    -4.4    234  1.2
  8250   16.1  61.0   250    8    4   6.8   3.7   27.6  81.7    -4.6    212  1.1
  8000   16.5  61.7   250    6    3   6.5   3.6   27.4  81.3    -4.9    190  1.0
  7750   17.0  62.6   225    5    3   7.6   4.1   27.1  80.8    -5.1    168  0.9
  7500   17.5  63.5   190    5    3   3.5   1.9   26.9  80.4    -5.4    146  0.7
  7250   17.5  63.5   170    7    4  -1.3  -0.7   26.2  79.1    -6.2    140  0.7
  7000   17.3  63.1   155    9    5  -2.1  -1.2   25.3  77.6    -7.1    137  0.7
  6750   17.2  63.0   155    9    5   3.3   1.8   24.5  76.1    -7.9    133  0.7
  6500   17.8  64.0   150    8    4   8.5   4.6   24.3  75.8    -8.1    109  0.6
  6250   18.3  64.9   145    7    4   7.0   3.8   24.1  75.5    -8.3     86  0.4
  6000   18.8  65.8   140    6    3   7.9   4.3   24.0  75.1    -8.5     63  0.3
  5750   19.4  66.9   135    6    3   5.7   3.1   23.8  74.8    -8.8     39  0.2
  5500   19.7  67.5   135    7    3   3.5   1.9   23.4  74.0    -9.2     23  0.1
  5250   19.7  67.5   130    7    4  -3.9  -2.1   22.7  72.9    -9.9     13  0.1
  5000   18.8  65.8   125    8    4 -21.2 -11.6   21.1  69.9   -11.6     35  0.2

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

           09/01/2015 at 0900 MDT          |       09/01/2015 at 1200 MDT
                                           |
K index... +27.1  LI... +270.8             | K index... +26.5  LI... +270.0
CAPE... +265.3  CIN... -15.3               | CAPE... +505.1  CIN... -17.0
                                           |
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 -64.0 -83.2  250  34 18   1.3   0.7 | -63.8 -82.8  250  37 19   0.7   0.4
 45000 -60.6 -77.1  250  47 24   4.4   2.4 | -60.9 -77.6  250  52 27   4.8   2.6
 40000 -53.5 -64.3  245  57 29   7.3   4.0 | -53.4 -64.1  245  62 32   7.0   3.8
 38000 -49.1 -56.4  250  53 27   7.4   4.1 | -49.1 -56.4  245  56 29   7.0   3.9
 36000 -44.6 -48.3  250  50 26   7.4   4.1 | -44.9 -48.8  240  51 26   7.0   3.9
 34000 -40.6 -41.1  245  41 21   6.5   3.6 | -40.6 -41.1  240  43 22   7.3   4.0
 32000 -36.7 -34.1  245  31 16   6.6   3.6 | -36.2 -33.2  240  36 18   7.3   4.0
 30000 -32.1 -25.8  245  28 14   7.0   3.9 | -31.6 -24.9  240  29 15   6.7   3.7
 29000 -30.0 -22.0  245  27 14   7.0   3.9 | -29.6 -21.3  240  26 13   6.7   3.7
 28000 -27.8 -18.0  245  26 13   7.8   4.3 | -27.6 -17.7  240  23 12   7.7   4.2
 27000 -25.4 -13.7  245  24 13   8.2   4.5 | -25.2 -13.4  240  22 11   8.0   4.4
 26000 -22.9  -9.2  245  23 12   8.2   4.5 | -22.8  -9.0  245  21 11   8.0   4.4
 25000 -20.5  -4.9  250  21 11   8.1   4.4 | -20.4  -4.7  245  20 10   7.9   4.3
 24000 -18.5  -1.3  250  19 10   6.7   3.7 | -18.3  -0.9  245  19 10   6.8   3.7
 23000 -16.5   2.3  250  18  9   6.7   3.7 | -16.3   2.7  250  18  9   6.8   3.7
 22000 -14.5   5.9  255  16  8   6.6   3.6 | -14.3   6.3  250  17  9   6.7   3.7
 21000 -12.8   9.0  255  14  7   5.9   3.2 | -12.5   9.5  250  14  7   6.1   3.4
 20000 -11.0  12.2  260  11  6   5.9   3.2 | -10.7  12.7  250  11  6   6.2   3.4
 19500 -10.1  13.8  265  10  5   5.8   3.2 |  -9.8  14.4  255  10  5   6.1   3.3
 19000  -9.2  15.4  270   9  4   6.9   3.8 |  -8.8  16.2  255   8  4   7.0   3.8
 18500  -8.1  17.4  280   7  4   7.0   3.8 |  -7.8  18.0  255   6  3   6.9   3.8
 18000  -7.1  19.2  295   6  3   7.2   4.0 |  -6.7  19.9  260   4  2   6.9   3.8
 17500  -6.0  21.2  305   6  3   7.8   4.3 |  -5.7  21.7  270   3  1   6.9   3.8
 17000  -4.8  23.4  320   6  3   7.8   4.3 |  -4.7  23.5  295   2  1   6.8   3.8
 16500  -3.7  25.3  325   6  3   8.0   4.4 |  -3.6  25.5  325   1  1   8.0   4.4
 16000  -2.6  27.3  320   5  3   8.0   4.4 |  -2.5  27.5  330   1  1   8.0   4.4
 15500  -1.5  29.3  320   5  2   7.3   4.0 |  -1.4  29.5  325   1  1   7.5   4.1
 15000  -0.5  31.1  300   4  2   6.9   3.8 |  -0.3  31.5  290   2  1   7.3   4.0
 14500   0.5  32.9  280   4  2   6.9   3.8 |   1.2  34.2  260   3  1   6.7   3.7
 14000   1.9  35.4  265   6  3   7.0   3.8 |   2.1  35.8  255   4  2   6.7   3.7
 13500   2.9  37.2  260   7  4   8.3   4.6 |   3.1  37.6  250   6  3   7.9   4.3
 13000   4.2  39.6  255   8  4   9.0   5.0 |   4.3  39.7  245   7  3   8.4   4.6
 12500   5.5  41.9  250   9  5   9.5   5.2 |   5.5  41.9  240   8  4   8.7   4.8
 12000   6.9  44.4  250   9  5   9.8   5.4 |   6.8  44.2  240   8  4   9.0   4.9
 11500   8.4  47.1  250   9  5   9.4   5.1 |   8.1  46.6  240   8  4   8.7   4.8
 11000   9.6  49.3  250   9  5   8.4   4.6 |   9.3  48.7  235   8  4   8.2   4.5
 10500  10.9  51.6  250   9  5   4.5   2.5 |  10.5  50.9  230   9  4   4.8   2.6
 10250  11.1  52.0  250   9  5   5.2   2.9 |  10.7  51.3  230   8  4   6.7   3.7
 10000  11.8  53.2  250   9  4  10.8   5.9 |  11.6  52.9  225   8  4  12.5   6.8
  9750  12.5  54.5  250   8  4  10.0   5.5 |  12.4  54.3  225   8  4  11.7   6.4
  9500  13.2  55.8  250   8  4   7.6   4.2 |  13.3  55.9  220   8  4   9.0   4.9
  9250  13.6  56.5  245   7  4   5.7   3.1 |  13.8  56.8  220   7  4   7.0   3.8
  9000  14.2  57.6  240   6  3   8.2   4.5 |  14.4  57.9  215   7  4   9.5   5.2
  8750  14.8  58.6  235   6  3   8.6   4.7 |  15.1  59.2  210   7  3   9.6   5.3
  8500  15.4  59.7  230   5  3   7.6   4.2 |  15.8  60.4  205   6  3   8.2   4.5
  8250  15.9  60.6  225   5  3   6.8   3.7 |  16.3  61.3  205   6  3   7.1   3.9
  8000  16.4  61.5  215   5  3   7.0   3.9 |  16.8  62.2  200   6  3   8.2   4.5
  7750  16.9  62.4  205   6  3   6.6   3.6 |  17.4  63.3  200   5  3   9.1   5.0
  7500  17.4  63.3  195   6  3   5.3   2.9 |  18.1  64.6  200   5  3   9.7   5.3
  7250  17.7  63.9  185   7  4   4.7   2.6 |  18.8  65.8  200   5  3  10.2   5.6
  7000  18.1  64.6  180   8  4   4.6   2.5 |  19.6  67.3  200   5  3   9.8   5.4
  6750  18.4  65.1  175   9  5   3.4   1.9 |  20.3  68.5  205   5  3  10.4   5.7
  6500  18.6  65.5  170   9  5   2.6   1.4 |  21.1  70.0  205   5  3  11.0   6.0
  6250  18.7  65.7  165   8  4   3.1   1.7 |  21.9  71.4  205   5  3  11.3   6.2
  6000  18.9  66.0  160   8  4   1.2   0.6 |  22.7  72.9  205   5  3  10.2   5.6
  5750  19.0  66.2  155   6  3   4.3   2.4 |  23.5  74.3  205   5  3  11.7   6.4
  5500  19.5  67.1  155   5  3   9.6   5.3 |  24.5  76.1  205   5  3  14.5   8.0
  5250  20.0  68.0  150   5  3   5.5   3.0 |  25.5  77.9  210   5  2  12.3   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/01/2015 at 1500 MDT          |       09/01/2015 at 1800 MDT
                                           |
K index... +25.1  LI... +270.6             | K index... +30.8  LI... +270.7
CAPE... +374.1  CIN... -25.5               | CAPE... +374.5  CIN... -16.8
                                           |
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 -64.0 -83.2  250  39 20   0.6   0.3 | -64.0 -83.2  250  40 20   0.6   0.3
 45000 -61.1 -78.0  250  55 28   4.8   2.6 | -61.2 -78.2  250  59 30   4.7   2.6
 40000 -53.6 -64.5  250  64 33   7.1   3.9 | -53.7 -64.7  250  68 35   7.5   4.1
 38000 -49.3 -56.7  245  59 30   7.1   3.9 | -49.1 -56.4  250  65 34   7.6   4.2
 36000 -45.0 -49.0  245  54 28   7.1   3.9 | -44.6 -48.3  255  63 32   7.6   4.2
 34000 -40.7 -41.3  245  48 25   7.2   3.9 | -40.1 -40.2  250  54 28   7.4   4.0
 32000 -36.4 -33.5  240  41 21   7.1   3.9 | -35.7 -32.3  245  44 23   7.3   4.0
 30000 -31.3 -24.3  240  34 18   7.6   4.2 | -30.8 -23.4  240  40 20   7.2   4.0
 29000 -29.0 -20.2  240  32 16   7.6   4.2 | -28.6 -19.5  240  38 20   7.2   4.0
 28000 -26.8 -16.2  240  29 15   7.8   4.3 | -26.5 -15.7  240  37 19   7.5   4.1
 27000 -24.4 -11.9  240  27 14   7.9   4.3 | -24.2 -11.6  240  34 18   7.6   4.2
 26000 -22.1  -7.8  245  26 13   7.9   4.3 | -22.0  -7.6  245  32 16   7.6   4.2
 25000 -19.7  -3.5  245  24 13   7.7   4.2 | -19.7  -3.5  245  29 15   7.5   4.1
 24000 -17.7   0.1  245  23 12   6.6   3.6 | -17.7   0.1  245  28 14   6.4   3.5
 23000 -15.8   3.6  245  21 11   6.6   3.6 | -15.8   3.6  250  27 14   6.4   3.5
 22000 -13.8   7.2  245  19 10   6.6   3.6 | -13.9   7.0  250  26 14   6.5   3.6
 21000 -11.9  10.6  240  15  8   6.6   3.6 | -11.9  10.6  250  22 11   6.7   3.7
 20000 -10.0  14.0  235  12  6   6.7   3.7 |  -9.9  14.2  250  18  9   6.7   3.7
 19500  -9.1  15.6  230  10  5   6.7   3.7 |  -8.9  16.0  250  16  8   6.6   3.6
 19000  -8.1  17.4  220   9  5   7.0   3.9 |  -7.9  17.8  245  14  7   8.1   4.4
 18500  -7.0  19.4  210   8  4   7.0   3.9 |  -6.7  19.9  245  13  7   8.1   4.4
 18000  -6.0  21.2  205   8  4   7.0   3.9 |  -5.6  21.9  245  12  6   7.8   4.3
 17500  -4.9  23.2  200   8  4   7.0   3.9 |  -4.6  23.7  240  12  6   7.1   3.9
 17000  -3.9  25.0  195   7  4   7.0   3.8 |  -3.6  25.5  240  12  6   7.2   3.9
 16500  -2.8  27.0  195   7  4   7.4   4.1 |  -2.6  27.3  240  13  6   7.0   3.8
 16000  -1.7  28.9  195   7  3   7.4   4.0 |  -1.6  29.1  240  13  6   7.0   3.9
 15500  -0.6  30.9  195   7  3   7.7   4.2 |  -0.6  30.9  240  13  6   7.6   4.2
 15000   0.5  32.9  200   7  4   7.9   4.3 |   0.5  32.9  240  12  6   7.9   4.3
 14500   2.2  36.0  205   7  4   7.3   4.0 |   2.2  36.0  245  12  6   8.1   4.5
 14000   3.3  37.9  210   8  4   7.3   4.0 |   3.4  38.1  245  11  6   8.2   4.5
 13500   4.3  39.7  215   8  4   7.4   4.0 |   4.6  40.3  245  11  5   8.4   4.6
 13000   5.3  41.5  220   8  4   7.5   4.1 |   5.8  42.4  245  10  5   8.6   4.7
 12500   6.4  43.5  225   8  4   8.0   4.4 |   7.0  44.6  245  10  5   8.9   4.9
 12000   7.6  45.7  230   7  4   8.6   4.7 |   8.4  47.1  245   9  5   9.1   5.0
 11500   8.9  48.0  235   7  4   8.8   4.8 |   9.7  49.5  245   9  4   9.0   4.9
 11000  10.1  50.2  235   7  3   8.7   4.8 |  11.0  51.8  245   8  4   8.4   4.6
 10500  11.4  52.5  240   6  3   5.1   2.8 |  12.3  54.1  240   7  4   5.2   2.9
 10250  11.7  53.1  240   6  3   6.1   3.3 |  12.6  54.7  240   7  3   5.9   3.2
 10000  12.4  54.3  240   6  3  11.6   6.4 |  13.3  55.9  235   6  3  10.5   5.8
  9750  13.2  55.8  240   6  3  10.7   5.9 |  14.0  57.2  235   6  3   9.7   5.3
  9500  14.0  57.2  240   5  3   8.8   4.8 |  14.7  58.5  230   5  3   8.3   4.6
  9250  14.5  58.1  240   5  3   7.4   4.0 |  15.2  59.4  230   5  2   7.3   4.0
  9000  15.1  59.2  240   5  2   9.4   5.1 |  15.9  60.6  230   4  2   8.7   4.8
  8750  15.8  60.4  240   4  2   9.3   5.1 |  16.5  61.7  225   4  2   8.7   4.8
  8500  16.5  61.7  240   4  2   9.6   5.3 |  17.2  63.0  220   3  2   8.5   4.7
  8250  17.2  63.0  240   4  2   9.9   5.5 |  17.8  64.0  220   3  2   8.2   4.5
  8000  17.9  64.2  240   4  2   9.8   5.4 |  18.4  65.1  215   3  1   8.3   4.5
  7750  18.6  65.5  240   4  2   9.9   5.4 |  19.0  66.2  215   2  1   8.3   4.5
  7500  19.4  66.9  240   4  2  10.1   5.6 |  19.6  67.3  215   2  1   9.1   5.0
  7250  20.1  68.2  240   4  2  10.4   5.7 |  20.3  68.5  215   2  1   9.7   5.3
  7000  20.9  69.6  240   4  2  10.0   5.5 |  21.0  69.8  220   2  1   9.5   5.2
  6750  21.6  70.9  240   4  2  10.1   5.5 |  21.7  71.1  220   2  1   9.9   5.4
  6500  22.4  72.3  240   4  2  10.5   5.8 |  22.5  72.5  220   2  1  10.3   5.7
  6250  23.2  73.8  240   4  2  11.0   6.0 |  23.2  73.8  220   2  1  10.8   5.9
  6000  24.0  75.2  240   4  2   9.6   5.3 |  24.0  75.2  220   2  1   9.5   5.2
  5750  24.8  76.6  240   4  2  12.1   6.6 |  24.7  76.5  220   2  1   8.9   4.9
  5500  25.8  78.4  240   4  2  16.0   8.8 |  25.4  77.7  220   2  1  10.1   5.6
  5250  26.9  80.4  245   4  2  13.0   7.1 |  26.1  79.0  225   2  1   9.2   5.0
  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 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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