Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 031256
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0655 MDT Thursday, September 3, 2015

This forecast is for Thursday, September 3, 2015:

If the trigger temperature of 79.4 F/26.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 463 ft/min (2.4 m/s)
   Maximum height of thermals.................. 12804 ft MSL (7965 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7832 ft MSL (2993 ft AGL)
Thermal soaring outlook for Friday 09/04....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:44:26 / 19:43:17 MDT
Total possible sunshine........... 12 hr 58 min 52 sec (778 min 52 sec)
Altitude of sun at 13:13:25 MDT... 58.33 degrees

Upper air data from rawinsonde observation taken on 09/03/2015 at 0600 MDT

Freezing level.................. 14878 ft MSL (10039 ft AGL)
Convective condensation level... 14214 ft MSL (9375 ft AGL)
Lifted condensation level....... 13957 ft MSL (9118 ft AGL)
Lifted index.................... -2.2
K index......................... +31.0

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  -63.3 -81.9   210   45   23  -4.4  -2.4   90.0 194.0    35.3      M    M
 45000  -62.5 -80.5   230   40   20   4.1   2.2   67.1 152.7    23.7      M    M
 40000  -55.2 -67.4   220   36   18   8.4   4.6   54.5 130.0    17.0      M    M
 38000  -50.7 -59.3   215   39   20   8.0   4.4   52.4 126.4    16.1      M    M
 36000  -47.4 -53.3   230   22   11   6.9   3.8   48.9 120.0    14.0      M    M
 34000  -42.1 -43.8   205   23   12   9.3   5.1   48.0 118.5    13.8      M    M
 32000  -37.0 -34.6   210   23   12   7.2   4.0   47.2 116.9    13.4      M    M
 30000  -31.3 -24.3   215   22   11   7.2   3.9   46.0 114.9    12.9      M    M
 29000  -29.0 -20.2   205   23   12   9.2   5.0   45.2 113.4    12.4      M    M
 28000  -26.6 -15.9   200   24   13   5.9   3.2   44.6 112.4    12.1      M    M
 27000  -24.8 -12.6   195   26   13   6.5   3.6   43.2 109.8    11.1      M    M
 26000  -22.8  -9.0   180   21   11   6.9   3.8   42.1 107.7    10.3      M    M
 25000  -20.7  -5.3   160   18    9   6.9   3.8   41.1 105.9     9.6      M    M
 24000  -18.9  -2.0   170    9    5   6.0   3.3   39.7 103.5     8.6      M    M
 23000  -16.8   1.8   200    3    2   7.2   3.9   38.7 101.7     7.8      M    M
 22000  -14.7   5.5   175    3    1   7.2   4.0   37.8 100.0     7.1      M    M
 21000  -12.4   9.7   155    3    2   8.3   4.5   37.1  98.7     6.5      M    M
 20000  -10.0  14.0   140    4    2   8.4   4.6   36.6  97.8     6.2      M    M
 19500   -8.7  16.3   145    5    2   9.0   5.0   36.3  97.4     6.0      M    M
 19000   -7.3  18.9   150    5    3   9.2   5.0   36.3  97.3     6.0      M    M
 18500   -5.9  21.4   160    7    3   8.5   4.7   36.2  97.1     6.0      M    M
 18000   -4.7  23.5   170    8    4   7.3   4.0   35.8  96.4     5.7      M    M
 17500   -3.6  25.5   175   10    5   6.8   3.7   35.4  95.7     5.4      M    M
 17000   -2.5  27.5   180   12    6  -0.8  -0.5   35.0  95.0     5.1      M    M
 16500   -3.2  26.2   185   14    7   7.1   3.9   32.2  90.0     2.2      M    M
 16000   -2.3  27.9   190   16    8   6.4   3.5   31.7  89.0     1.7      M    M
 15500   -1.3  29.7   200   15    8   8.2   4.5   31.2  88.2     1.2      M    M
 15000   -0.1  31.8   210   15    8   8.3   4.6   31.0  87.7     1.0      M    M
 14500    1.2  34.2   220   15    8   8.3   4.6   30.7  87.3     0.8      M    M
 14000    2.4  36.3   230   16    8   8.3   4.6   30.5  87.0     0.6      M    M
 13500    3.6  38.5   235   17    9   8.3   4.6   30.3  86.5     0.3      M    M
 13000    4.8  40.6   240   18    9   8.3   4.6   30.0  86.0     0.1      M    M
 12500    6.0  42.8   245   20   10   8.3   4.6   29.8  85.6    -0.2    626  3.2
 12000    7.2  45.0   250   21   11   8.5   4.7   29.6  85.3    -0.4    574  2.9
 11500    8.4  47.1   255   21   11   6.7   3.7   29.2  84.6    -0.7    526  2.7
 11000    9.3  48.7   260   21   11   6.5   3.6   28.8  83.8    -1.2    483  2.5
 10500   10.4  50.7   255   23   12   9.4   5.2   28.4  83.2    -1.6    436  2.2
 10250   11.0  51.8   255   23   12   8.7   4.8   28.4  83.1    -1.7    409  2.1
 10000   11.6  52.9   255   23   12   7.8   4.3   28.3  82.9    -1.8    384  1.9
  9750   12.2  54.0   255   21   11   8.1   4.4   28.1  82.7    -2.0    359  1.8
  9500   12.8  55.0   255   19   10   8.0   4.4   28.0  82.4    -2.1    333  1.7
  9250   13.4  56.1   255   17    9   8.0   4.4   27.9  82.2    -2.2    308  1.6
  9000   14.0  57.2   255   15    8   8.0   4.4   27.8  82.0    -2.3    283  1.4
  8750   14.6  58.3   255   13    7   8.0   4.4   27.6  81.7    -2.5    258  1.3
  8500   15.2  59.4   260   11    5   8.0   4.4   27.5  81.5    -2.6    233  1.2
  8250   15.8  60.4   265    8    4   8.0   4.4   27.4  81.3    -2.8    207  1.1
  8000   16.4  61.5   270    6    3   8.0   4.4   27.3  81.1    -2.9    182  0.9
  7750   17.0  62.6   260    5    2   8.0   4.4   27.1  80.8    -3.0    157  0.8
  7500   17.6  63.7   245    3    2   8.0   4.4   27.0  80.5    -3.2    132  0.7
  7250   18.2  64.8   215    3    1   8.0   4.4   26.8  80.3    -3.3    107  0.5
  7000   18.8  65.8   175    3    1   8.0   4.4   26.7  80.1    -3.5     81  0.4
  6750   19.4  66.9   160    5    3   8.1   4.4   26.6  79.8    -3.6     56  0.3
  6500   20.0  68.0   160    8    4   7.9   4.3   26.4  79.6    -3.8     31  0.2
  6250   20.5  68.9   155   11    5   6.2   3.4   26.2  79.2    -4.0      7  0.0
  6000   20.9  69.6   155   13    7   5.1   2.8   25.9  78.6    -4.3      M    M
  5750   21.3  70.3   155   12    6   5.5   3.0   25.6  78.0    -4.7      M    M
  5500   21.6  70.9   150   10    5   5.2   2.9   25.2  77.4    -5.0      M    M
  5250   22.0  71.6   150    8    4   5.8   3.2   24.9  76.8    -5.4      M    M
  5000   22.4  72.3   145    6    3   3.9   2.1   24.6  76.3    -5.8      M    M

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

           09/03/2015 at 0900 MDT          |       09/03/2015 at 1200 MDT
                                           |
K index... +32.5  LI... +271.2             | K index... +31.2  LI... +270.2
CAPE... +331.0  CIN... -33.9               | CAPE... +697.8  CIN... -10.7
                                           |
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 -62.8 -81.0  235  39 20   0.9   0.5 | -62.6 -80.7  230  37 19   0.7   0.4
 45000 -60.7 -77.3  230  44 22   2.9   1.6 | -60.9 -77.6  225  47 24   2.5   1.4
 40000 -55.6 -68.1  225  40 21   7.6   4.2 | -56.3 -69.3  225  47 24   7.9   4.3
 38000 -51.0 -59.8  225  37 19   7.6   4.2 | -51.5 -60.7  220  41 21   7.9   4.3
 36000 -46.4 -51.5  230  34 18   7.6   4.2 | -46.8 -52.2  215  36 18   7.8   4.3
 34000 -41.7 -43.1  225  28 15   7.9   4.3 | -41.7 -43.1  210  32 17   8.7   4.8
 32000 -37.0 -34.6  220  22 11   7.9   4.4 | -36.5 -33.7  205  30 15   8.7   4.8
 30000 -32.2 -26.0  210  19 10   8.1   4.5 | -31.5 -24.7  200  24 13   8.1   4.5
 29000 -29.8 -21.6  200  18  9   8.1   4.5 | -29.1 -20.4  200  21 11   8.2   4.5
 28000 -27.4 -17.3  195  17  9   8.1   4.5 | -26.7 -16.1  200  18  9   8.1   4.5
 27000 -24.6 -12.3  195  14  7   7.6   4.2 | -24.0 -11.2  200  15  7   7.1   3.9
 26000 -22.3  -8.1  200  11  6   7.6   4.2 | -21.9  -7.4  205  12  6   7.2   3.9
 25000 -20.1  -4.2  210   8  4   7.6   4.2 | -19.8  -3.6  215   9  5   7.2   3.9
 24000 -18.1  -0.6  220   6  3   6.7   3.7 | -17.8  -0.0  225   8  4   6.6   3.6
 23000 -16.1   3.0  235   4  2   6.7   3.7 | -15.9   3.4  235   7  4   6.6   3.6
 22000 -14.1   6.6  265   3  2   6.7   3.7 | -13.9   7.0  245   7  4   6.7   3.7
 21000 -12.1  10.2  300   2  1   6.9   3.8 | -12.0  10.4  250   5  3   6.7   3.7
 20000 -10.1  13.8  035   2  1   6.9   3.8 | -10.0  14.0  250   3  2   6.8   3.7
 19500  -9.2  15.4  050   3  2   6.9   3.8 |  -9.0  15.8  250   2  1   6.8   3.7
 19000  -8.2  17.2  060   4  2   6.4   3.5 |  -8.1  17.4  250   2  1   6.1   3.4
 18500  -7.3  18.9  075   4  2   6.3   3.5 |  -7.2  19.0  245   2  1   6.0   3.3
 18000  -6.4  20.5  090   4  2   6.3   3.5 |  -6.3  20.7  245   3  1   6.0   3.3
 17500  -5.5  22.1  115   3  2   6.2   3.4 |  -5.5  22.1  250   4  2   5.7   3.1
 17000  -4.6  23.7  150   3  2   6.3   3.4 |  -4.7  23.5  255   6  3   5.7   3.2
 16500  -3.7  25.3  185   4  2   5.8   3.2 |  -3.9  25.0  260   8  4   5.7   3.1
 16000  -2.9  26.8  215   5  3   5.8   3.2 |  -3.0  26.6  260  10  5   5.7   3.1
 15500  -2.0  28.4  225   8  4   5.9   3.3 |  -2.2  28.0  260  12  6   6.1   3.3
 15000  -1.2  29.8  230  10  5   6.1   3.4 |  -1.3  29.7  260  13  7   6.5   3.6
 14500  -0.3  31.5  235  11  6   6.2   3.4 |  -0.4  31.3  260  14  7   6.6   3.6
 14000   0.7  33.3  240  12  6   6.8   3.7 |   0.6  33.1  255  14  7   7.4   4.0
 13500   1.6  34.9  240  13  7   6.6   3.6 |   2.2  36.0  255  15  8   7.4   4.1
 13000   3.3  37.9  240  13  7   8.4   4.6 |   3.3  37.9  255  15  8   7.6   4.2
 12500   4.5  40.1  240  14  7   8.7   4.8 |   4.4  39.9  250  16  8   7.6   4.2
 12000   5.8  42.4  240  14  7   9.2   5.0 |   5.5  41.9  250  15  8   7.7   4.2
 11500   7.1  44.8  240  14  7   9.0   4.9 |   6.6  43.9  245  15  8   7.9   4.3
 11000   8.4  47.1  235  13  7   8.2   4.5 |   7.8  46.0  240  13  7   8.3   4.5
 10500   9.6  49.3  230  12  6   5.2   2.8 |   9.0  48.2  240  12  6   5.4   3.0
 10250   9.9  49.8  230  12  6   6.2   3.4 |   9.3  48.7  235  12  6   7.0   3.9
 10000  10.6  51.1  225  12  6  10.9   6.0 |  10.1  50.2  235  11  6  12.0   6.6
  9750  11.4  52.5  225  11  6  10.0   5.5 |  10.9  51.6  230  10  5  11.2   6.2
  9500  12.1  53.8  225  11  6   8.7   4.8 |  11.7  53.1  230  10  5   9.3   5.1
  9250  12.7  54.9  220  11  5   7.4   4.0 |  12.3  54.1  225   9  5   7.6   4.2
  9000  13.3  55.9  220  10  5   8.8   4.8 |  12.9  55.2  220   9  5   9.6   5.3
  8750  13.9  57.0  215  10  5   9.4   5.2 |  13.6  56.5  215   9  5  10.3   5.7
  8500  14.6  58.3  210  10  5   8.5   4.7 |  14.3  57.7  210   9  5   9.1   5.0
  8250  15.2  59.4  205  11  5   7.6   4.2 |  14.9  58.8  205   9  5   7.9   4.3
  8000  15.7  60.3  205  11  6   7.4   4.1 |  15.5  59.9  200   9  5   7.6   4.2
  7750  16.3  61.3  200  11  6   7.3   4.0 |  16.0  60.8  195   9  5   7.2   3.9
  7500  16.8  62.2  195  12  6   6.3   3.5 |  16.6  61.9  195   9  5   7.9   4.3
  7250  17.2  63.0  185  13  7   5.7   3.1 |  17.1  62.8  190   9  5   8.2   4.5
  7000  17.6  63.7  180  14  7   5.3   2.9 |  17.7  63.9  185   9  5   8.4   4.6
  6750  18.0  64.4  180  15  8   4.3   2.3 |  18.3  64.9  185   9  5   9.6   5.3
  6500  18.2  64.8  175  14  7   4.1   2.2 |  19.1  66.4  185   9  5  10.5   5.7
  6250  18.5  65.3  170  13  7   4.1   2.3 |  19.9  67.8  185   9  5  11.3   6.2
  6000  18.7  65.7  165  12  6   3.9   2.1 |  20.7  69.3  185   9  5   9.3   5.1
  5750  19.0  66.2  160   9  5   4.9   2.7 |  21.3  70.3  185   9  4  10.3   5.6
  5500  19.4  66.9  160   8  4   6.1   3.3 |  22.2  72.0  185   8  4  13.5   7.4
  5250  19.7  67.5  160   7  4   5.2   2.9 |  23.1  73.6  185   8  4  11.0   6.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/03/2015 at 1500 MDT          |       09/03/2015 at 1800 MDT
                                           |
K index... +30.1  LI... +270.5             | K index... +28.0  LI... +270.7
CAPE... +549.0  CIN... -43.5               | CAPE... +658.9  CIN... -40.9
                                           |
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 -62.8 -81.0  230  36 19  -0.5  -0.3 | -63.3 -81.9  230  36 18  -0.1  -0.1
 45000 -62.0 -79.6  225  52 27   3.9   2.1 | -61.8 -79.2  230  53 27   4.6   2.5
 40000 -55.5 -67.9  220  47 24   7.2   3.9 | -54.3 -65.7  220  52 27   6.8   3.7
 38000 -51.2 -60.2  210  40 21   7.2   3.9 | -50.3 -58.5  220  50 26   6.8   3.7
 36000 -46.8 -52.2  200  34 18   7.1   3.9 | -46.2 -51.2  220  47 24   6.8   3.7
 34000 -41.6 -42.9  200  30 15   9.0   5.0 | -41.7 -43.1  220  42 22   7.8   4.3
 32000 -36.2 -33.2  195  25 13   9.1   5.0 | -37.0 -34.6  215  37 19   7.8   4.3
 30000 -31.2 -24.2  200  24 12   8.3   4.6 | -32.3 -26.1  215  33 17   7.9   4.3
 29000 -28.7 -19.7  205  24 12   8.3   4.6 | -29.9 -21.8  215  31 16   7.9   4.4
 28000 -25.6 -14.1  210  23 12   7.1   3.9 | -27.6 -17.7  215  30 15   8.0   4.4
 27000 -23.7 -10.7  215  24 12   6.5   3.6 | -24.6 -12.3  215  29 15   7.9   4.3
 26000 -21.8  -7.2  225  25 13   6.5   3.6 | -22.3  -8.1  220  30 15   7.9   4.3
 25000 -19.9  -3.8  230  26 14   6.5   3.6 | -19.9  -3.8  225  30 16   7.9   4.3
 24000 -17.9  -0.2  235  25 13   6.5   3.6 | -17.7   0.1  225  29 15   7.2   3.9
 23000 -16.0   3.2  240  23 12   6.5   3.6 | -15.6   3.9  230  27 14   7.2   3.9
 22000 -14.0   6.8  245  21 11   6.6   3.6 | -13.4   7.9  235  26 13   7.2   3.9
 21000 -12.0  10.4  250  19 10   7.0   3.9 | -11.4  11.5  240  24 13   6.5   3.6
 20000  -9.9  14.2  255  17  9   7.0   3.9 |  -9.5  14.9  245  23 12   6.5   3.6
 19500  -8.9  16.0  255  16  8   7.1   3.9 |  -8.6  16.5  245  23 12   6.5   3.6
 19000  -7.9  17.8  260  15  8   7.0   3.8 |  -7.6  18.3  250  22 12   6.8   3.7
 18500  -6.9  19.6  260  15  8   7.0   3.8 |  -6.6  20.1  250  22 11   6.9   3.8
 18000  -5.9  21.4  260  15  8   6.9   3.8 |  -5.6  21.9  255  22 11   6.8   3.7
 17500  -4.9  23.2  260  15  8   6.2   3.4 |  -4.6  23.7  255  22 12   6.1   3.3
 17000  -4.0  24.8  255  15  8   6.3   3.4 |  -3.7  25.3  255  23 12   6.1   3.3
 16500  -3.1  26.4  255  15  8   6.3   3.4 |  -2.8  27.0  255  23 12   6.4   3.5
 16000  -2.2  28.0  255  16  8   6.3   3.4 |  -1.9  28.6  255  24 12   6.6   3.6
 15500  -1.3  29.7  250  16  8   6.2   3.4 |  -1.1  30.0  255  25 13   7.1   3.9
 15000  -0.5  31.1  250  17  9   6.1   3.3 |  -0.1  31.8  250  24 12   7.8   4.3
 14500   0.3  32.5  250  17  9   6.2   3.4 |   1.0  33.8  250  24 12   8.1   4.4
 14000   1.3  34.3  250  18  9   7.4   4.1 |   2.1  35.8  250  22 12   8.4   4.6
 13500   2.8  37.0  250  18  9   7.6   4.2 |   3.2  37.8  245  20 10   8.5   4.7
 13000   4.0  39.2  250  18  9   7.9   4.3 |   4.9  40.8  240  17  9   7.9   4.4
 12500   5.1  41.2  250  17  9   8.0   4.4 |   6.1  43.0  235  15  8   8.1   4.4
 12000   6.3  43.3  245  16  8   8.3   4.6 |   7.3  45.1  235  14  7   8.5   4.7
 11500   7.5  45.5  240  15  8   8.3   4.5 |   8.6  47.5  230  12  6   8.4   4.6
 11000   8.7  47.7  240  13  7   7.9   4.3 |   9.7  49.5  225  11  5   7.2   4.0
 10500   9.8  49.6  235  12  6   5.4   3.0 |  10.7  51.3  215   9  5  10.1   5.5
 10250  10.1  50.2  230  11  5   6.2   3.4 |  11.6  52.9  210   9  5  10.5   5.8
 10000  10.8  51.4  230  10  5  10.1   5.6 |  12.1  53.8  205   8  4   7.1   3.9
  9750  11.5  52.7  225   9  5   9.4   5.1 |  12.7  54.9  200   8  4   8.0   4.4
  9500  12.2  54.0  225   8  4   8.6   4.7 |  13.3  55.9  195   8  4   7.7   4.2
  9250  12.7  54.9  220   8  4   7.1   3.9 |  13.8  56.8  185   8  4   7.8   4.3
  9000  13.2  55.8  215   7  4   7.7   4.2 |  14.4  57.9  180   8  4   8.0   4.4
  8750  13.8  56.8  210   7  3   8.0   4.4 |  15.0  59.0  175   8  4   8.0   4.4
  8500  14.4  57.9  205   6  3   7.6   4.2 |  15.6  60.1  170   9  5   7.9   4.3
  8250  14.9  58.8  195   6  3   7.4   4.0 |  16.1  61.0  165   9  5   7.6   4.2
  8000  15.4  59.7  185   7  3   6.9   3.8 |  16.7  62.1  160   9  5   6.9   3.8
  7750  15.9  60.6  175   7  4   6.4   3.5 |  17.1  62.8  160  10  5   6.1   3.4
  7500  16.4  61.5  165   8  4   7.0   3.8 |  17.6  63.7  155  10  5   7.4   4.1
  7250  16.9  62.4  160   8  4   7.7   4.2 |  18.2  64.8  155  10  5   8.8   4.8
  7000  17.4  63.3  155   9  5   6.8   3.7 |  18.8  65.8  155  10  5   9.2   5.1
  6750  17.9  64.2  150   9  5   6.9   3.8 |  19.5  67.1  155   9  5   9.8   5.4
  6500  18.5  65.3  145   9  5   9.8   5.4 |  20.2  68.4  155   9  5  10.1   5.5
  6250  19.3  66.7  145   9  5  11.2   6.2 |  21.0  69.8  155   9  5  10.3   5.7
  6000  20.1  68.2  145   9  5  10.4   5.7 |  21.7  71.1  155   9  4  10.2   5.6
  5750  20.8  69.4  145   9  4   9.8   5.4 |  22.5  72.5  155   8  4   9.6   5.3
  5500  21.5  70.7  145   9  4   9.8   5.4 |  23.1  73.6  155   8  4   8.8   4.8
  5250  22.2  72.0  145   8  4   9.9   5.4 |  23.8  74.8  155   8  4   8.8   4.8
  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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