Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 251301
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0701 MDT Friday, July 25, 2014

This forecast is for Friday, July 25, 2014:

If the trigger temperature of 86.8 F/30.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 972 ft/min (4.9 m/s)
   Maximum height of thermals.................. 15599 ft MSL (10760 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1100 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................. 9582 ft MSL (4743 ft AGL)
Thermal soaring outlook for Saturday 07/26..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:08:36 / 20:32:56 MDT
Total possible sunshine........... 14 hr 24 min 19 sec (864 min 19 sec)
Altitude of sun at 13:20:36 MDT... 70.40 degrees

Upper air data from rawinsonde observation taken on 07/25/2014 at 0600 MDT

Freezing level.................. 16522 ft MSL (11683 ft AGL)
Convective condensation level... 15016 ft MSL (10177 ft AGL)
Lifted condensation level....... 15312 ft MSL (10472 ft AGL)
Lifted index.................... -1.5
K index......................... +29.9

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  -72.0 -97.6   245   41   21   9.8   5.4   73.0 163.3    22.7      M    M
 45000  -61.7 -79.1   260   48   25  10.0   5.5   65.6 150.1    19.8      M    M
 40000  -52.3 -62.1   240   45   23   8.4   4.6   57.6 135.6    15.8      M    M
 38000  -47.4 -53.3   240   43   22   8.1   4.4   55.9 132.7    15.1      M    M
 36000  -41.9 -43.4   240   40   20   7.6   4.2   54.5 130.1    14.5      M    M
 34000  -36.9 -34.4   235   34   18   7.6   4.2   53.4 128.0    14.1      M    M
 32000  -33.0 -27.4   240   30   15   8.4   4.6   50.8 123.4    12.5      M    M
 30000  -27.7 -17.9   260   30   15   9.0   4.9   50.0 122.0    12.2      M    M
 29000  -25.0 -13.0   260   27   14   8.6   4.7   49.5 121.1    12.0      M    M
 28000  -22.4  -8.3   255   25   13   8.6   4.7   49.1 120.3    11.8      M    M
 27000  -19.8  -3.6   255   23   12   7.2   4.0   48.7 119.7    11.6      M    M
 26000  -18.3  -0.9   250   20   10   4.4   2.4   46.9 116.4    10.3      M    M
 25000  -16.1   3.0   245   18    9   8.0   4.4   46.1 114.9     9.8      M    M
 24000  -13.8   7.2   245   17    9   7.5   4.1   45.2 113.4     9.2      M    M
 23000  -12.1  10.2   255   18    9  -1.6  -0.9   43.8 110.8     8.1      M    M
 22000  -10.3  13.5   265   20   10   6.3   3.5   42.4 108.3     7.0      M    M
 21000  -10.7  12.7   245   19   10   2.4   1.3   38.9 102.0     3.8      M    M
 20000   -8.9  16.0   225   20   10   1.9   1.0   37.7  99.8     2.7      M    M
 19500   -7.7  18.1   245   21   11  15.6   8.5   36.6  97.8     1.7      M    M
 19000   -6.0  21.2   250   20   10   8.7   4.8   36.9  98.4     1.9      M    M
 18500   -4.8  23.4   255   20   10   8.4   4.6   36.6  98.0     1.7      M    M
 18000   -3.5  25.7   265   20   10   8.4   4.6   36.4  97.5     1.5      M    M
 17500   -2.2  28.0   270   20   10   8.4   4.6   36.2  97.2     1.4      M    M
 17000   -1.0  30.2   275   20   10   8.5   4.7   36.0  96.8     1.2      M    M
 16500    0.2  32.4   275   21   11   8.5   4.6   35.8  96.4     1.0      M    M
 16000    1.5  34.7   275   21   11   6.6   3.6   35.6  96.1     0.8      M    M
 15500    1.8  35.2   270   22   11   5.8   3.2   34.5  94.2    -0.4    965  4.9
 15000    3.1  37.6   265   22   11   8.8   4.8   34.4  93.9    -0.6    911  4.6
 14500    4.4  39.9   260   23   12   9.0   4.9   34.2  93.6    -0.7    857  4.4
 14000    5.7  42.3   255   24   12   9.0   4.9   34.1  93.4    -0.9    802  4.1
 13500    7.0  44.6   245   25   13   9.5   5.2   34.0  93.2    -1.0    748  3.8
 13000    8.2  46.8   240   27   14   7.3   4.0   33.8  92.8    -1.3    699  3.6
 12500    9.3  48.7   240   25   13   7.6   4.2   33.4  92.2    -1.7    650  3.3
 12000   10.5  50.9   245   23   12   7.5   4.1   33.1  91.6    -2.0    601  3.1
 11500   11.7  53.1   245   19   10   8.9   4.9   32.8  91.1    -2.3    549  2.8
 11000   13.0  55.4   245   15    8   8.9   4.9   32.7  90.8    -2.4    495  2.5
 10500   14.3  57.7   245   11    6   8.7   4.8   32.5  90.6    -2.6    441  2.2
 10250   14.9  58.8   245   10    5   8.3   4.6   32.4  90.4    -2.7    415  2.1
 10000   15.6  60.1   240    8    4   8.4   4.6   32.3  90.2    -2.8    389  2.0
  9750   16.2  61.2   235    6    3   8.4   4.6   32.2  90.0    -2.9    363  1.8
  9500   16.8  62.2   225    5    3   8.4   4.6   32.1  89.8    -3.0    337  1.7
  9250   17.4  63.3   210    4    2   8.4   4.6   32.0  89.7    -3.1    311  1.6
  9000   18.0  64.4   185    3    2   8.4   4.6   31.9  89.5    -3.2    285  1.4
  8750   18.7  65.7   170    3    2   8.4   4.6   31.8  89.3    -3.4    259  1.3
  8500   19.3  66.7   155    4    2   8.4   4.6   31.7  89.1    -3.5    233  1.2
  8250   19.9  67.8   150    4    2   8.4   4.6   31.6  88.9    -3.6    207  1.1
  8000   20.5  68.9   140    5    3   8.4   4.6   31.5  88.7    -3.7    181  0.9
  7750   21.1  70.0   135    6    3   8.1   4.5   31.4  88.5    -3.8    155  0.8
  7500   21.5  70.7   130    8    4  -1.9  -1.0   31.0  87.8    -4.2    138  0.7
  7250   21.0  69.8   125   10    5  -3.9  -2.2   29.8  85.6    -5.5    145  0.7
  7000   21.1  70.0   125   12    6   5.1   2.8   29.2  84.5    -6.1    135  0.7
  6750   21.5  70.7   125   14    7   5.6   3.1   28.9  84.0    -6.4    115  0.6
  6500   21.9  71.4   130   16    8   7.0   3.8   28.6  83.4    -6.8     95  0.5
  6250   22.3  72.1   130   19   10   0.9   0.5   28.3  82.9    -7.1     75  0.4
  6000   21.9  71.4   130   21   11  -9.0  -4.9   27.1  80.8    -8.3     80  0.4
  5750   21.4  70.5   130   20   10   1.3   0.7   25.9  78.7    -9.5     88  0.4
  5500   22.0  71.6   125   18    9  10.6   5.8   25.8  78.5    -9.6     62  0.3
  5250   22.6  72.7   125   15    8   6.1   3.3   25.7  78.3    -9.8     36  0.2
  5000   22.8  73.0   120   13    7   0.1   0.1   25.2  77.4   -10.4     24  0.1

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

           07/25/2014 at 0900 MDT          |       07/25/2014 at 1200 MDT
                                           |
K index... +34.2  LI... -2.9               | K index... +31.5  LI... -3.1
CAPE... +334.6  CIN... -36.7               | CAPE... +563.3  CIN... -18.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -67.3 -89.1  260  32 17   1.1   0.6 | -67.6 -89.7  255  31 16   1.7   0.9
 45000 -62.5 -80.5  255  47 24   7.1   3.9 | -61.7 -79.1  255  46 23   7.2   3.9
 40000 -51.1 -60.0  250  46 24   8.0   4.4 | -50.7 -59.3  250  45 23   7.9   4.4
 38000 -46.3 -51.3  245  44 23   8.0   4.4 | -45.9 -50.6  245  44 23   7.9   4.4
 36000 -41.5 -42.7  245  42 22   7.8   4.3 | -41.1 -42.0  245  43 22   8.1   4.4
 34000 -36.8 -34.2  245  38 19   7.7   4.2 | -36.2 -33.2  245  41 21   8.1   4.5
 32000 -32.2 -26.0  245  33 17   8.6   4.7 | -31.4 -24.5  245  38 19   8.6   4.7
 30000 -27.4 -17.3  245  29 15   8.1   4.5 | -26.4 -15.5  240  30 15   7.4   4.1
 29000 -25.0 -13.0  250  27 14   8.1   4.5 | -24.2 -11.6  240  26 13   7.4   4.1
 28000 -22.1  -7.8  250  25 13   6.9   3.8 | -22.1  -7.8  235  24 12   6.9   3.8
 27000 -20.0  -4.0  250  25 13   6.9   3.8 | -20.1  -4.2  240  24 12   6.9   3.8
 26000 -18.0  -0.4  250  24 12   6.9   3.8 | -18.0  -0.4  240  24 13   6.9   3.8
 25000 -16.1   3.0  250  24 12   5.0   2.7 | -16.0   3.2  240  24 13   6.1   3.4
 24000 -14.7   5.5  250  22 11   4.6   2.5 | -14.3   6.3  245  22 12   5.9   3.3
 23000 -13.4   7.9  250  20 10   4.6   2.5 | -12.5   9.5  245  21 11   6.0   3.3
 22000 -12.0  10.4  255  18  9   6.8   3.7 | -10.8  12.6  245  19 10   6.5   3.6
 21000  -9.9  14.2  250  16  8   7.2   3.9 |  -8.9  16.0  240  17  9   6.6   3.6
 20000  -7.8  18.0  240  15  8   7.2   4.0 |  -6.9  19.6  240  16  8   6.6   3.6
 19500  -6.8  19.8  240  14  7   7.4   4.0 |  -6.0  21.2  240  15  8   6.6   3.6
 19000  -5.7  21.7  235  14  7   7.6   4.2 |  -5.0  23.0  240  15  8   6.5   3.5
 18500  -4.6  23.7  235  14  7   7.6   4.2 |  -4.1  24.6  245  16  8   6.5   3.6
 18000  -3.5  25.7  235  14  7   7.8   4.3 |  -3.2  26.2  245  16  8   6.3   3.5
 17500  -2.4  27.7  235  15  7   7.8   4.3 |  -2.3  27.9  250  17  9   6.3   3.5
 17000  -1.3  29.7  235  15  8   7.8   4.3 |  -1.4  29.5  255  17  9   6.4   3.5
 16500  -0.2  31.6  235  15  8   7.7   4.2 |  -0.5  31.1  255  17  9   6.6   3.6
 16000   0.9  33.6  235  15  8   7.7   4.2 |   0.5  32.9  260  18  9   6.5   3.6
 15500   2.0  35.6  235  15  8   8.0   4.4 |   1.5  34.7  260  18  9   7.7   4.2
 15000   3.1  37.6  240  15  8   8.0   4.4 |   2.6  36.7  265  17  9   7.7   4.2
 14500   4.2  39.6  240  15  8   8.3   4.6 |   3.8  38.8  265  17  9   7.9   4.3
 14000   5.5  41.9  245  16  8   8.4   4.6 |   5.5  41.9  265  17  9   8.0   4.4
 13500   7.3  45.1  250  18  9   8.5   4.6 |   6.8  44.2  265  17  9   8.6   4.7
 13000   8.6  47.5  250  19 10   8.4   4.6 |   8.0  46.4  260  17  9   8.6   4.7
 12500   9.8  49.6  250  19 10   8.7   4.8 |   9.3  48.7  260  17  9   9.5   5.2
 12000  11.1  52.0  250  19 10   8.7   4.8 |  10.7  51.3  255  17  9   9.7   5.3
 11500  12.4  54.3  245  19 10   8.7   4.8 |  12.1  53.8  255  17  9   9.3   5.1
 11000  13.7  56.7  245  18  9   9.0   4.9 |  13.4  56.1  250  16  8   9.3   5.1
 10500  14.7  58.5  240  17  9   4.5   2.4 |  14.5  58.1  250  16  8   5.6   3.1
 10250  15.1  59.2  240  16  8   7.5   4.1 |  15.0  59.0  245  15  8   8.6   4.7
 10000  15.9  60.6  235  15  8  11.0   6.0 |  15.7  60.3  245  14  7  11.4   6.3
  9750  16.6  61.9  235  14  7  10.0   5.5 |  16.5  61.7  245  13  7  10.7   5.9
  9500  17.3  63.1  230  13  7   7.7   4.3 |  17.2  63.0  245  12  6   7.4   4.1
  9250  17.7  63.9  230  12  6   6.7   3.7 |  17.6  63.7  240  11  6   7.0   3.8
  9000  18.3  64.9  230  11  6   8.0   4.4 |  18.2  64.8  240  10  5   9.5   5.2
  8750  18.9  66.0  225  10  5   7.7   4.2 |  18.9  66.0  235   9  5   9.0   5.0
  8500  19.4  66.9  220  10  5   7.2   4.0 |  19.6  67.3  235   9  4   9.2   5.0
  8250  20.0  68.0  220   9  5   6.9   3.8 |  20.2  68.4  235   9  4   9.3   5.1
  8000  20.5  68.9  215   9  5   6.9   3.8 |  20.9  69.6  235   8  4  10.1   5.6
  7750  21.0  69.8  210   9  5   6.5   3.6 |  21.7  71.1  235   8  4  10.5   5.7
  7500  21.4  70.5  200  10  5   5.7   3.2 |  22.5  72.5  235   8  4  10.0   5.5
  7250  21.8  71.2  195  10  5   5.8   3.2 |  23.2  73.8  235   8  4  10.1   5.5
  7000  22.2  72.0  190  11  6   4.8   2.7 |  23.9  75.0  235   8  4   9.7   5.3
  6750  22.5  72.5  180  12  6   4.0   2.2 |  24.7  76.5  235   8  4  10.3   5.6
  6500  22.8  73.0  175  11  6   4.5   2.5 |  25.5  77.9  235   8  4  11.1   6.1
  6250  23.1  73.6  175  10  5   4.5   2.4 |  26.3  79.3  235   8  4  11.3   6.2
  6000  23.4  74.1  170  10  5   4.4   2.4 |  27.1  80.8  235   7  4  10.0   5.5
  5750  23.8  74.8  165   9  4   8.3   4.5 |  27.8  82.0  235   7  4  12.2   6.7
  5500  24.6  76.3  165   8  4  11.7   6.4 |  28.9  84.0  235   7  4  15.9   8.7
  5250  25.4  77.7  165   8  4   9.1   5.0 |  30.0  86.0  235   7  4  13.0   7.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/25/2014 at 1500 MDT          |       07/25/2014 at 1800 MDT
                                           |
K index... +29.7  LI... -1.9               | K index... +29.1  LI... -2.8
CAPE... +143.6  CIN... -37.3               | CAPE... +364.6  CIN... -25.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -67.8 -90.0  255  33 17   1.4   0.8 | -67.3 -89.1  255  32 16   0.9   0.5
 45000 -62.4 -80.3  255  46 24   7.6   4.2 | -62.3 -80.1  250  44 23   7.8   4.3
 40000 -50.3 -58.5  245  46 24   7.7   4.2 | -50.2 -58.4  240  49 25   7.7   4.2
 38000 -45.7 -50.3  240  44 23   7.7   4.2 | -45.6 -50.1  235  48 25   7.7   4.2
 36000 -41.1 -42.0  240  42 22   7.9   4.3 | -41.0 -41.8  235  47 24   7.7   4.2
 34000 -36.3 -33.3  240  40 21   7.9   4.4 | -36.3 -33.3  240  41 21   7.7   4.2
 32000 -31.5 -24.7  245  39 20   8.3   4.5 | -31.7 -25.1  245  35 18   8.2   4.5
 30000 -27.1 -16.8  245  33 17   7.4   4.1 | -27.1 -16.8  250  32 16   7.9   4.3
 29000 -24.4 -11.9  240  29 15   7.5   4.1 | -24.1 -11.4  250  31 16   8.0   4.4
 28000 -22.2  -8.0  240  27 14   7.5   4.1 | -21.9  -7.4  250  30 15   7.2   4.0
 27000 -20.0  -4.0  240  26 13   7.5   4.1 | -19.8  -3.6  250  29 15   7.3   4.0
 26000 -17.8  -0.0  240  25 13   7.6   4.2 | -17.6   0.3  245  29 15   7.3   4.0
 25000 -15.7   3.7  240  24 12   5.8   3.2 | -15.6   3.9  245  28 14   6.1   3.3
 24000 -14.1   6.6  245  22 11   5.4   3.0 | -13.9   7.0  250  26 13   5.8   3.2
 23000 -12.5   9.5  245  20 10   5.5   3.0 | -12.2  10.0  255  24 12   5.8   3.2
 22000 -10.9  12.4  250  19 10   6.2   3.4 | -10.5  13.1  260  22 11   5.9   3.3
 21000  -9.0  15.8  250  20 10   6.3   3.5 |  -8.8  16.2  265  21 11   6.0   3.3
 20000  -7.2  19.0  255  21 11   6.3   3.5 |  -7.1  19.2  270  20 10   6.0   3.3
 19500  -6.3  20.7  255  21 11   6.7   3.7 |  -6.2  20.8  275  20 10   5.9   3.2
 19000  -5.2  22.6  255  22 11   7.4   4.1 |  -5.4  22.3  280  19 10   5.7   3.1
 18500  -4.1  24.6  255  22 11   7.5   4.1 |  -4.5  23.9  285  18 10   5.7   3.1
 18000  -3.1  26.4  260  22 11   6.6   3.6 |  -3.7  25.3  290  18  9   6.5   3.6
 17500  -2.1  28.2  260  22 11   6.5   3.6 |  -2.7  27.1  290  18  9   6.7   3.7
 17000  -1.2  29.8  260  22 11   6.6   3.6 |  -1.7  28.9  295  17  9   6.9   3.8
 16500  -0.2  31.6  265  21 11   6.7   3.7 |  -0.6  30.9  295  17  9   7.5   4.1
 16000   0.7  33.3  265  20 11   6.6   3.6 |   0.5  32.9  295  16  8   7.4   4.1
 15500   1.7  35.1  265  20 10   7.7   4.2 |   1.6  34.9  290  16  8   8.4   4.6
 15000   2.8  37.0  270  19 10   7.6   4.2 |   2.8  37.0  285  16  8   8.4   4.6
 14500   3.9  39.0  270  18  9   7.8   4.3 |   4.1  39.4  280  16  8   8.8   4.8
 14000   5.6  42.1  270  17  9   7.7   4.2 |   6.0  42.8  275  16  8   9.0   4.9
 13500   6.9  44.4  270  16  8   9.0   5.0 |   7.4  45.3  270  16  8   9.2   5.1
 13000   8.2  46.8  270  16  8   9.0   4.9 |   8.7  47.7  265  15  8   9.2   5.1
 12500   9.5  49.1  265  15  8   9.1   5.0 |  10.1  50.2  260  14  7   9.2   5.0
 12000  10.9  51.6  265  15  7   9.1   5.0 |  11.4  52.5  255  14  7   9.2   5.0
 11500  12.2  54.0  265  14  7   9.3   5.1 |  12.7  54.9  250  13  7   9.1   5.0
 11000  13.6  56.5  265  14  7   9.7   5.3 |  14.1  57.4  245  12  6   9.3   5.1
 10500  14.8  58.6  265  13  7   5.8   3.2 |  15.2  59.4  240  12  6   5.3   2.9
 10250  15.3  59.5  260  13  7   9.1   5.0 |  15.7  60.3  235  11  6   8.8   4.9
 10000  16.1  61.0  260  13  7  11.5   6.3 |  16.5  61.7  230  11  6  12.0   6.6
  9750  16.9  62.4  260  12  6  10.8   5.9 |  17.3  63.1  230  11  6  11.4   6.2
  9500  17.7  63.9  260  12  6   8.0   4.4 |  18.1  64.6  225  11  5   9.0   4.9
  9250  18.2  64.8  255  11  6   7.6   4.2 |  18.7  65.7  220  10  5   8.2   4.5
  9000  18.8  65.8  250  10  5   9.6   5.3 |  19.4  66.9  215  10  5   9.9   5.4
  8750  19.5  67.1  245   9  5   9.1   5.0 |  20.1  68.2  210  10  5   9.4   5.2
  8500  20.1  68.2  240   9  4   8.7   4.8 |  20.8  69.4  200  10  5   8.3   4.6
  8250  20.7  69.3  235   8  4   8.5   4.6 |  21.3  70.3  195  10  5   7.6   4.2
  8000  21.4  70.5  230   7  4   8.7   4.8 |  21.9  71.4  185  10  5   8.3   4.6
  7750  22.0  71.6  225   7  4   9.1   5.0 |  22.5  72.5  180  11  5   8.6   4.7
  7500  22.7  72.9  220   7  3   9.6   5.3 |  23.1  73.6  180  11  6   8.8   4.9
  7250  23.4  74.1  220   6  3   9.9   5.4 |  23.7  74.7  180  11  6   9.3   5.1
  7000  24.1  75.4  215   6  3   9.3   5.1 |  24.4  75.9  175  11  6   8.1   4.5
  6750  24.8  76.6  215   6  3   9.6   5.2 |  25.0  77.0  175  11  6   8.7   4.8
  6500  25.5  77.9  215   6  3  10.3   5.6 |  25.7  78.3  175  11  6  10.7   5.9
  6250  26.3  79.3  215   6  3  10.2   5.6 |  26.5  79.7  175  11  6  11.1   6.1
  6000  27.0  80.6  210   6  3   9.9   5.4 |  27.3  81.1  175  11  6   9.9   5.4
  5750  27.7  81.9  210   6  3   9.1   5.0 |  28.0  82.4  175  11  5  10.6   5.8
  5500  28.4  83.1  210   6  3   8.7   4.8 |  28.9  84.0  175  10  5  12.7   7.0
  5250  29.0  84.2  210   6  3   9.0   4.9 |  29.8  85.6  175  10  5  11.0   6.0
  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 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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