Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 031238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Monday, August 3, 2015

This forecast is for Monday, August 3, 2015:

If the trigger temperature of 75.4 F/24.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 564 ft/min (2.9 m/s)
   Maximum height of thermals.................. 14162 ft MSL (9323 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1045 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................. 10700 ft MSL (5860 ft AGL)
Thermal soaring outlook for Tuesday 08/04...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:16:15 / 20:24:43 MDT
Total possible sunshine........... 14 hr 8 min 28 sec (848 min 28 sec)
Altitude of sun at 13:20:14 MDT... 68.29 degrees

Upper air data from rawinsonde observation taken on 08/03/2015 at 0600 MDT

Freezing level.................. 14670 ft MSL (9831 ft AGL)
Convective condensation level... 11830 ft MSL (6991 ft AGL)
Lifted condensation level....... 12707 ft MSL (7868 ft AGL)
Lifted index.................... -1.6
K index......................... +29.3

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  -66.6 -87.9   265   25   13   5.5   3.0   82.5 180.5    31.2      M    M
 45000  -61.0 -77.8   230   49   25   6.7   3.7   67.4 153.3    24.0      M    M
 40000  -48.9 -56.0   230   53   27   7.1   3.9   63.5 146.3    23.1      M    M
 38000  -44.6 -48.3   235   43   22   7.2   4.0   61.3 142.3    22.1      M    M
 36000  -40.8 -41.4   210   29   15   1.2   0.6   57.3 135.1    20.0      M    M
 34000  -38.1 -36.6   210   35   18   6.1   3.4   52.8 127.0    17.2      M    M
 32000  -34.5 -30.1   235   28   15   6.7   3.7   49.8 121.6    15.5      M    M
 30000  -29.4 -20.9   220   19   10   8.8   4.8   48.8 119.9    15.1      M    M
 29000  -26.8 -16.2   215   20   10   8.2   4.5   48.3 119.0    14.9      M    M
 28000  -24.3 -11.7   210   21   11   7.2   3.9   47.7 117.8    14.6      M    M
 27000  -22.8  -9.0   225   21   11   5.0   2.7   46.0 114.8    13.3      M    M
 26000  -20.7  -5.3   240   23   12   8.2   4.5   45.0 112.9    12.6      M    M
 25000  -18.2  -0.8   245   19   10   9.0   4.9   44.5 112.1    12.3      M    M
 24000  -15.6   3.9   240   12    6   6.4   3.5   44.1 111.4    12.1      M    M
 23000  -13.9   7.0   215    7    4   7.0   3.8   42.6 108.7    11.0      M    M
 22000  -12.8   9.0   220   12    6   3.2   1.7   40.4 104.8     9.3      M    M
 21000  -10.9  12.4   210   19   10   7.8   4.3   39.3 102.7     8.4      M    M
 20000   -8.4  16.9   205   19   10   6.0   3.3   38.8 101.8     8.1      M    M
 19500   -8.0  17.6   205   19   10   2.0   1.1   36.9  98.4     6.4      M    M
 19000   -7.6  18.3   200   19   10   5.0   2.8   35.6  96.2     5.3      M    M
 18500   -6.7  19.9   195   18    9   6.1   3.4   35.0  95.0     4.7      M    M
 18000   -5.9  21.4   190   18    9   6.2   3.4   34.4  93.9     4.2      M    M
 17500   -5.0  23.0   185   18    9   6.2   3.4   33.8  92.9     3.6      M    M
 17000   -4.1  24.6   180   18    9   6.2   3.4   33.3  91.9     3.1      M    M
 16500   -3.2  26.2   190   18    9   6.2   3.4   32.7  90.8     2.6      M    M
 16000   -2.3  27.9   195   18    9   6.2   3.4   32.1  89.7     2.0      M    M
 15500   -1.4  29.5   200   17    9   6.3   3.4   31.5  88.7     1.5      M    M
 15000   -0.5  31.1   205   16    8   6.3   3.4   30.9  87.6     0.9      M    M
 14500    0.4  32.7   200   15    8   6.3   3.4   30.3  86.6     0.3      M    M
 14000    1.3  34.3   195   15    8   6.3   3.5   29.7  85.5    -0.2    747  3.8
 13500    2.2  36.0   200   15    8   6.2   3.4   29.1  84.4    -0.8    705  3.6
 13000    3.2  37.8   210   15    8   7.9   4.4   28.7  83.6    -1.3    661  3.4
 12500    4.4  39.9   215   15    8   8.1   4.5   28.4  83.1    -1.6    610  3.1
 12000    5.6  42.1   220   16    8   8.2   4.5   28.1  82.7    -1.8    560  2.8
 11500    6.7  44.1   220   18    9   7.2   3.9   27.8  82.1    -2.2    511  2.6
 11000    7.7  45.9   215   20   10   7.1   3.9   27.4  81.3    -2.7    467  2.4
 10500    8.6  47.5   215   21   11   7.1   3.9   27.0  80.5    -3.2    423  2.1
 10250    9.1  48.4   215   22   11   6.3   3.5   26.7  80.1    -3.4    401  2.0
 10000    9.5  49.1   215   22   11   6.0   3.3   26.4  79.6    -3.8    381  1.9
  9750   10.0  50.0   210   21   11   5.6   3.1   26.1  79.1    -4.1    361  1.8
  9500   10.4  50.7   205   19   10   7.4   4.1   25.8  78.5    -4.4    340  1.7
  9250   11.1  52.0   200   18    9   9.3   5.1   25.8  78.4    -4.4    313  1.6
  9000   11.7  53.1   195   17    9   8.8   4.8   25.7  78.3    -4.5    286  1.5
  8750   12.4  54.3   190   17    9   8.9   4.9   25.7  78.2    -4.6    259  1.3
  8500   13.0  55.4   185   18    9   8.9   4.9   25.6  78.1    -4.7    232  1.2
  8250   13.7  56.7   180   18    9   8.9   4.9   25.5  78.0    -4.8    205  1.0
  8000   14.4  57.9   175   19   10   9.0   4.9   25.5  77.9    -4.8    177  0.9
  7750   15.0  59.0   175   19   10   8.8   4.8   25.4  77.7    -4.9    150  0.8
  7500   15.7  60.3   170   19   10   9.4   5.2   25.3  77.6    -5.0    123  0.6
  7250   16.3  61.3   170   19   10   7.1   3.9   25.3  77.5    -5.1     96  0.5
  7000   16.6  61.9   165   19   10   2.3   1.2   24.9  76.8    -5.5     80  0.4
  6750   16.7  62.1   160   17    9   1.3   0.7   24.2  75.6    -6.2     71  0.4
  6500   16.7  62.1   155   15    8   0.9   0.5   23.6  74.5    -6.9     62  0.3
  6250   16.8  62.2   150   13    7   3.7   2.0   23.0  73.3    -7.6     53  0.3
  6000   17.3  63.1   140   11    6   7.2   3.9   22.7  72.9    -7.9     31  0.2
  5750   17.8  64.0   135   10    5   6.4   3.5   22.5  72.4    -8.1      9  0.0
  5500   18.3  64.9   130    9    5   7.7   4.2   22.2  72.0    -8.4      M    M
  5250   18.8  65.8   130    8    4   3.3   1.8   22.0  71.6    -8.6      M    M
  5000   18.6  65.5   125    7    3  -6.1  -3.4   21.1  70.1    -9.5      M    M

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

           08/03/2015 at 0900 MDT          |       08/03/2015 at 1200 MDT
                                           |
K index... +28.1  LI... +271.2             | K index... +29.9  LI... +268.7
CAPE... +389.2  CIN... -21.8               | CAPE... +1123.1  CIN... M
                                           |
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 -65.8 -86.4  235  32 17   2.7   1.5 | -64.9 -84.8  235  29 15   3.1   1.7
 45000 -59.4 -74.9  235  48 25   7.6   4.2 | -58.6 -73.5  230  43 22   6.5   3.5
 40000 -48.1 -54.6  235  52 27   4.7   2.6 | -48.7 -55.7  230  49 25   5.1   2.8
 38000 -45.3 -49.5  230  41 21   4.7   2.6 | -45.7 -50.3  230  41 21   5.1   2.8
 36000 -42.4 -44.3  225  30 15   4.6   2.5 | -42.6 -44.7  230  34 18   4.9   2.7
 34000 -38.5 -37.3  225  25 13   6.8   3.7 | -38.7 -37.7  230  31 16   6.9   3.8
 32000 -34.5 -30.1  230  21 11   6.7   3.7 | -34.5 -30.1  235  28 14   6.8   3.7
 30000 -29.7 -21.5  230  20 11   8.3   4.5 | -30.0 -22.0  240  25 13   7.9   4.3
 29000 -27.2 -17.0  230  21 11   8.3   4.5 | -27.6 -17.7  240  24 12   7.9   4.3
 28000 -24.7 -12.5  230  21 11   8.1   4.5 | -24.6 -12.3  240  22 11   8.2   4.5
 27000 -21.8  -7.2  230  22 11   7.8   4.3 | -22.2  -8.0  240  22 11   8.2   4.5
 26000 -19.5  -3.1  235  22 11   7.8   4.3 | -19.8  -3.6  240  21 11   8.2   4.5
 25000 -17.1   1.2  240  23 12   7.6   4.2 | -17.3   0.9  235  21 11   7.9   4.3
 24000 -15.1   4.8  240  22 11   6.6   3.6 | -15.4   4.3  240  21 11   6.3   3.4
 23000 -13.1   8.4  240  21 11   6.6   3.6 | -13.5   7.7  240  21 11   6.3   3.4
 22000 -11.2  11.8  240  20 10   6.4   3.5 | -11.6  11.1  240  22 11   6.1   3.3
 21000  -9.5  14.9  240  20 10   5.6   3.1 | -10.0  14.0  240  21 11   5.5   3.0
 20000  -8.0  17.6  245  19 10   5.8   3.2 |  -8.5  16.7  245  21 11   5.6   3.1
 19500  -7.2  19.0  245  19 10   6.1   3.3 |  -7.7  18.1  245  21 11   5.7   3.1
 19000  -6.4  20.5  245  18  9   5.6   3.1 |  -6.9  19.6  245  21 11   5.7   3.1
 18500  -5.6  21.9  250  18  9   5.6   3.1 |  -6.1  21.0  250  22 11   5.7   3.1
 18000  -4.8  23.4  250  18  9   5.6   3.1 |  -5.3  22.5  255  23 12   5.7   3.1
 17500  -4.0  24.8  255  19 10   5.6   3.1 |  -4.5  23.9  255  25 13   5.5   3.0
 17000  -3.2  26.2  255  19 10   5.7   3.1 |  -3.7  25.3  260  27 14   5.5   3.0
 16500  -2.4  27.7  255  20 10   5.1   2.8 |  -2.9  26.8  260  29 15   5.5   3.0
 16000  -1.7  28.9  255  20 10   5.1   2.8 |  -2.1  28.2  265  31 16   5.6   3.1
 15500  -1.0  30.2  255  20 10   5.0   2.7 |  -1.3  29.7  265  32 17   5.7   3.2
 15000  -0.3  31.5  255  21 11   4.9   2.7 |  -0.5  31.1  265  33 17   5.9   3.3
 14500   0.4  32.7  255  21 11   5.0   2.7 |   0.4  32.7  265  34 17   6.0   3.3
 14000   1.1  34.0  255  21 11   5.8   3.2 |   1.3  34.3  265  33 17   6.6   3.6
 13500   1.9  35.4  255  21 11   5.8   3.2 |   2.7  36.9  265  32 17   6.9   3.8
 13000   3.2  37.8  250  21 11   6.2   3.4 |   3.7  38.7  260  30 16   7.2   4.0
 12500   4.1  39.4  250  20 10   6.6   3.6 |   4.7  40.5  255  29 15   7.2   4.0
 12000   5.1  41.2  245  19 10   7.3   4.0 |   5.6  42.1  245  27 14   7.2   4.0
 11500   6.1  43.0  245  19 10   7.5   4.1 |   6.6  43.9  240  25 13   7.4   4.0
 11000   7.2  45.0  240  17  9   8.0   4.4 |   7.6  45.7  235  22 11   7.5   4.1
 10500   8.4  47.1  235  16  8   4.7   2.6 |   8.7  47.7  230  20 10   4.0   2.2
 10250   8.6  47.5  235  16  8   6.0   3.3 |   8.8  47.8  230  18  9   5.5   3.0
 10000   9.3  48.7  235  15  8  11.1   6.1 |   9.5  49.1  225  16  8  11.3   6.2
  9750  10.0  50.0  235  15  7  10.3   5.7 |  10.2  50.4  220  15  8  10.3   5.6
  9500  10.7  51.3  230  14  7   8.6   4.7 |  10.9  51.6  215  13  7   8.9   4.9
  9250  11.2  52.2  230  13  7   6.1   3.4 |  11.5  52.7  215  12  6   8.2   4.5
  9000  11.7  53.1  225  13  7   7.3   4.0 |  12.2  54.0  215  11  6  10.4   5.7
  8750  12.2  54.0  225  12  6   7.9   4.3 |  12.9  55.2  210  11  6  10.9   6.0
  8500  12.7  54.9  220  11  6   7.6   4.2 |  13.7  56.7  210  10  5  10.2   5.6
  8250  13.3  55.9  215  11  6   7.6   4.2 |  14.4  57.9  210  10  5   9.4   5.2
  8000  13.8  56.8  210  11  6   6.9   3.8 |  15.1  59.2  210  10  5   9.8   5.4
  7750  14.2  57.6  200  11  6   6.2   3.4 |  15.8  60.4  210  10  5   9.9   5.4
  7500  14.7  58.5  195  11  6   5.6   3.1 |  16.6  61.9  210  10  5  10.0   5.5
  7250  15.0  59.0  190  12  6   5.3   2.9 |  17.3  63.1  210  10  5  10.1   5.5
  7000  15.4  59.7  185  12  6   4.7   2.6 |  18.1  64.6  215  10  5  10.0   5.5
  6750  15.7  60.3  175  12  6   5.0   2.8 |  18.8  65.8  215   9  5  10.4   5.7
  6500  16.2  61.2  175  11  6   7.2   4.0 |  19.6  67.3  215   9  5  10.9   6.0
  6250  16.7  62.1  170  10  5   8.1   4.5 |  20.4  68.7  215   9  5  11.6   6.3
  6000  17.3  63.1  170   9  5   6.8   3.7 |  21.3  70.3  215   9  5   9.5   5.2
  5750  17.7  63.9  165   8  4   8.4   4.6 |  21.9  71.4  215   8  4  12.1   6.6
  5500  18.5  65.3  165   8  4  11.4   6.2 |  23.1  73.6  215   8  4  17.0   9.3
  5250  19.3  66.7  165   8  4   9.0   5.0 |  24.2  75.6  220   8  4  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/03/2015 at 1500 MDT          |       08/03/2015 at 1800 MDT
                                           |
K index... +30.8  LI... +270.2             | K index... +24.8  LI... +271.3
CAPE... +532.0  CIN... -1.2                | CAPE... +549.5  CIN... -10.6
                                           |
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 -64.0 -83.2  235  26 14   3.3   1.8 | -62.9 -81.2  230  24 12   3.7   2.1
 45000 -58.2 -72.8  230  41 21   5.3   2.9 | -57.0 -70.6  230  38 19   4.5   2.5
 40000 -49.8 -57.6  235  44 23   5.5   3.0 | -49.8 -57.6  240  33 17   4.7   2.6
 38000 -46.5 -51.7  230  37 19   5.5   3.0 | -47.0 -52.6  235  30 15   4.7   2.6
 36000 -43.2 -45.8  220  30 15   5.4   3.0 | -44.1 -47.4  235  26 14   4.4   2.4
 34000 -38.8 -37.8  215  26 13   7.4   4.1 | -39.7 -39.5  235  25 13   7.8   4.3
 32000 -34.4 -29.9  215  22 11   7.2   4.0 | -35.0 -31.0  235  23 12   7.8   4.3
 30000 -29.7 -21.5  220  20 10   8.0   4.4 | -30.7 -23.3  240  24 13   7.2   4.0
 29000 -27.3 -17.1  220  19 10   8.0   4.4 | -28.5 -19.3  245  26 13   7.2   4.0
 28000 -24.4 -11.9  225  18  9   7.1   3.9 | -25.8 -14.4  250  27 14   6.6   3.6
 27000 -22.3  -8.1  235  20 10   7.0   3.9 | -23.9 -11.0  255  29 15   6.5   3.6
 26000 -20.2  -4.4  240  23 12   7.0   3.9 | -21.9  -7.4  260  30 16   6.6   3.6
 25000 -18.1  -0.6  245  25 13   6.9   3.8 | -20.0  -4.0  265  32 16   6.8   3.7
 24000 -16.2   2.8  250  27 14   6.4   3.5 | -17.8  -0.0  270  33 17   7.6   4.2
 23000 -14.3   6.3  255  29 15   6.4   3.5 | -15.5   4.1  275  35 18   7.6   4.2
 22000 -12.4   9.7  260  30 16   6.3   3.5 | -13.3   8.1  285  36 19   7.6   4.2
 21000 -10.6  12.9  260  31 16   6.1   3.4 | -11.0  12.2  285  39 20   7.6   4.2
 20000  -8.8  16.2  260  31 16   6.2   3.4 |  -8.6  16.5  285  41 21   7.7   4.2
 19500  -7.9  17.8  260  31 16   6.3   3.4 |  -7.5  18.5  285  43 22   7.8   4.3
 19000  -7.1  19.2  260  32 16   5.7   3.1 |  -6.4  20.5  285  43 22   6.2   3.4
 18500  -6.3  20.7  260  32 17   5.8   3.2 |  -5.5  22.1  285  43 22   6.3   3.4
 18000  -5.4  22.3  260  33 17   5.7   3.1 |  -4.6  23.7  285  43 22   6.2   3.4
 17500  -4.6  23.7  260  34 17   5.6   3.1 |  -3.8  25.2  285  42 21   6.0   3.3
 17000  -3.8  25.2  260  34 18   5.6   3.1 |  -2.9  26.8  280  40 21   6.2   3.4
 16500  -3.0  26.6  260  35 18   5.8   3.2 |  -2.1  28.2  280  39 20   5.8   3.2
 16000  -2.2  28.0  260  36 18   5.8   3.2 |  -1.3  29.7  275  38 20   5.9   3.2
 15500  -1.4  29.5  260  36 19   6.1   3.4 |  -0.5  31.1  275  38 19   6.6   3.6
 15000  -0.4  31.3  260  37 19   6.3   3.5 |   0.5  32.9  275  37 19   7.0   3.9
 14500   0.5  32.9  260  37 19   6.5   3.6 |   1.5  34.7  270  37 19   7.2   4.0
 14000   1.4  34.5  260  36 18   7.0   3.8 |   2.6  36.7  270  36 19   7.7   4.2
 13500   2.9  37.2  255  34 17   7.5   4.1 |   4.2  39.6  270  36 19   8.2   4.5
 13000   4.0  39.2  250  30 16   7.8   4.3 |   5.4  41.7  270  35 18   8.6   4.7
 12500   5.1  41.2  245  27 14   8.1   4.5 |   6.7  44.1  265  34 18   8.8   4.8
 12000   6.3  43.3  245  24 12   8.5   4.7 |   7.9  46.2  265  33 17   9.0   4.9
 11500   7.4  45.3  240  20 10   9.0   5.0 |   9.2  48.6  260  31 16   9.0   5.0
 11000   8.9  48.0  235  18  9   9.7   5.3 |  10.5  50.9  260  29 15   9.0   4.9
 10500  10.3  50.5  235  16  8   6.2   3.4 |  11.8  53.2  260  26 14   6.2   3.4
 10250  10.6  51.1  235  16  8   7.3   4.0 |  12.1  53.8  255  25 13   6.8   3.7
 10000  11.5  52.7  235  16  8  12.8   7.0 |  12.8  55.0  255  23 12  11.0   6.0
  9750  12.3  54.1  235  16  8  12.0   6.6 |  13.5  56.3  255  22 11  10.2   5.6
  9500  13.2  55.8  235  15  8   9.8   5.4 |  14.2  57.6  255  20 10   9.2   5.1
  9250  13.8  56.8  235  15  8   8.3   4.6 |  14.9  58.8  255  19 10   8.8   4.8
  9000  14.5  58.1  235  15  8  10.3   5.7 |  15.6  60.1  255  18  9  10.1   5.5
  8750  15.3  59.5  235  14  7  10.2   5.6 |  16.3  61.3  255  18  9  10.0   5.5
  8500  16.1  61.0  235  14  7  10.4   5.7 |  17.0  62.6  255  17  9  10.0   5.5
  8250  16.8  62.2  235  14  7  10.6   5.8 |  17.7  63.9  255  16  8   9.9   5.4
  8000  17.6  63.7  235  13  7  10.1   5.5 |  18.5  65.3  255  16  8   9.7   5.3
  7750  18.3  64.9  235  13  7   9.8   5.4 |  19.2  66.6  255  16  8   9.4   5.2
  7500  19.1  66.4  235  13  7  10.2   5.6 |  19.9  67.8  255  16  8   9.9   5.4
  7250  19.8  67.6  235  12  6  10.5   5.7 |  20.6  69.1  255  15  8  10.4   5.7
  7000  20.6  69.1  235  12  6  10.2   5.6 |  21.4  70.5  255  15  8   9.8   5.4
  6750  21.3  70.3  235  12  6  10.2   5.6 |  22.1  71.8  255  15  8   9.5   5.2
  6500  22.1  71.8  235  11  6  10.4   5.7 |  22.8  73.0  255  14  7  10.4   5.7
  6250  22.9  73.2  235  11  6  11.1   6.1 |  23.6  74.5  260  14  7  11.0   6.0
  6000  23.7  74.7  235  11  6   9.0   4.9 |  24.4  75.9  260  14  7  10.1   5.5
  5750  24.3  75.7  235  10  5  10.6   5.8 |  25.2  77.4  260  13  7   9.9   5.4
  5500  25.3  77.5  235  10  5  14.6   8.0 |  25.9  78.6  260  12  6  11.0   6.1
  5250  26.2  79.2  235  10  5  11.4   6.3 |  26.7  80.1  260  12  6  10.5   5.8
  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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