Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271236
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Sunday, July 27, 2014

This forecast is for Sunday, July 27, 2014:

If the trigger temperature of 86.0 F/30.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1262 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18659 ft MSL (13820 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
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................. 12093 ft MSL (7254 ft AGL)
Thermal soaring outlook for Monday 07/28....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:10:19 / 20:31:14 MDT
Total possible sunshine........... 14 hr 20 min 55 sec (860 min 55 sec)
Altitude of sun at 13:20:35 MDT... 69.95 degrees

Upper air data from rawinsonde observation taken on 07/27/2014 at 0600 MDT

Freezing level.................. 16359 ft MSL (11520 ft AGL)
Convective condensation level... 15817 ft MSL (10978 ft AGL)
Lifted condensation level....... 16604 ft MSL (11764 ft AGL)
Lifted index.................... -3.1
K index......................... +25.3

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  -72.2 -98.0   265   12    6   4.5   2.5   73.0 163.3    21.4      M    M
 45000  -61.2 -78.2   210   20   10   5.6   3.1   65.8 150.4    18.6      M    M
 40000  -52.0 -61.6   220   31   16   8.3   4.6   57.4 135.4    14.3      M    M
 38000  -47.0 -52.6   220   33   17   8.3   4.6   56.1 133.0    13.7      M    M
 36000  -41.9 -43.4   220   31   16  11.0   6.1   55.0 131.1    13.3      M    M
 34000  -36.9 -34.4   225   27   14   8.4   4.6   53.8 128.9    12.8      M    M
 32000  -31.8 -25.2   230   23   12   9.9   5.4   53.0 127.3    12.4      M    M
 30000  -26.6 -15.9   230   19   10   7.2   4.0   51.1 124.0    11.4      M    M
 29000  -24.3 -11.7   240   18    9   7.9   4.4   50.2 122.4    10.9      M    M
 28000  -21.9  -7.4   250   17    9   8.0   4.4   49.5 121.2    10.4      M    M
 27000  -19.6  -3.3   255   16    8   4.6   2.5   48.8 119.8    10.0      M    M
 26000  -18.5  -1.3   265   17    9   8.9   4.9   46.5 115.6     8.2      M    M
 25000  -15.7   3.7   275   17    9   8.4   4.6   46.3 115.4     8.2      M    M
 24000  -14.4   6.1   275   17    9   4.8   2.6   44.5 112.1     6.7      M    M
 23000  -13.3   8.1   270   18    9   3.5   1.9   42.5 108.4     4.9      M    M
 22000  -11.5  11.3   270   18    9   8.9   4.9   41.2 106.2     3.9      M    M
 21000   -9.1  15.6   265   19   10   4.3   2.4   40.6 105.0     3.3      M    M
 20000   -7.5  18.5   265   19   10   4.3   2.4   39.0 102.2     2.0      M    M
 19500   -6.9  19.6   255   21   11   5.9   3.2   38.1 100.6     1.2      M    M
 19000   -6.1  21.0   255   19   10   6.6   3.6   37.4  99.3     0.5      M    M
 18500   -5.2  22.6   250   17    9   6.4   3.5   36.8  98.2    -0.1   1257  6.4
 18000   -4.4  24.1   245   15    7   6.5   3.6   36.2  97.2    -0.6   1215  6.2
 17500   -3.5  25.7   240   12    6   7.8   4.3   35.7  96.3    -1.2   1174  6.0
 17000   -1.4  29.5   230   10    5   9.0   4.9   35.5  95.9    -1.3   1091  5.5
 16500   -0.1  31.8   220    8    4   9.0   4.9   35.4  95.8    -1.4   1036  5.3
 16000    1.3  34.3   200    7    3   9.0   4.9   35.3  95.6    -1.5    980  5.0
 15500    2.6  36.7   180    6    3   9.0   4.9   35.2  95.3    -1.7    925  4.7
 15000    4.0  39.2   155    6    3   9.0   4.9   35.0  95.0    -1.8    870  4.4
 14500    5.3  41.5   135    7    4   9.0   4.9   34.9  94.8    -1.9    814  4.1
 14000    6.7  44.1   125    9    5   9.0   4.9   34.8  94.6    -2.0    759  3.9
 13500    7.9  46.2   120    9    4   8.0   4.4   34.6  94.2    -2.2    707  3.6
 13000    9.1  48.4   115    8    4   8.1   4.4   34.3  93.7    -2.5    656  3.3
 12500   10.3  50.5   110    8    4   8.2   4.5   34.0  93.2    -2.8    606  3.1
 12000   11.4  52.5   105    8    4   7.3   4.0   33.7  92.7    -3.1    557  2.8
 11500   12.4  54.3   095    7    4   7.5   4.1   33.3  92.0    -3.6    514  2.6
 11000   13.6  56.5   085    6    3   8.7   4.8   33.1  91.6    -3.9    462  2.3
 10500   14.9  58.8   070    6    3   8.5   4.7   32.9  91.3    -4.0    408  2.1
 10250   15.5  59.9   080    6    3   8.4   4.6   32.8  91.1    -4.2    383  1.9
 10000   16.1  61.0   085    6    3   8.4   4.6   32.7  90.9    -4.3    358  1.8
  9750   16.7  62.1   095    6    3   8.4   4.6   32.6  90.7    -4.5    332  1.7
  9500   17.3  63.1   100    6    3   8.6   4.7   32.5  90.5    -4.6    307  1.6
  9250   17.8  64.0   110    7    3   4.6   2.5   32.3  90.2    -4.8    285  1.4
  9000   18.0  64.4   115    7    4   1.6   0.9   31.7  89.1    -5.4    273  1.4
  8750   18.1  64.6   110    7    4   2.0   1.1   31.1  88.1    -6.1    262  1.3
  8500   18.2  64.8   100    7    4   4.6   2.5   30.6  87.1    -6.6    250  1.3
  8250   18.7  65.7   095    8    4   7.3   4.0   30.4  86.6    -6.9    228  1.2
  8000   19.2  66.6   090    8    4   6.6   3.6   30.1  86.2    -7.1    206  1.0
  7750   19.7  67.5   090    8    4   6.8   3.7   29.9  85.8    -7.4    183  0.9
  7500   20.2  68.4   085    8    4   6.7   3.7   29.7  85.4    -7.6    161  0.8
  7250   20.7  69.3   085    8    4   6.7   3.7   29.4  85.0    -7.9    139  0.7
  7000   21.2  70.2   080    8    4   6.7   3.7   29.2  84.6    -8.1    117  0.6
  6750   21.7  71.1   080    7    4   6.8   3.7   29.0  84.1    -8.4     95  0.5
  6500   22.2  72.0   075    7    3   6.4   3.5   28.7  83.7    -8.6     73  0.4
  6250   22.7  72.9   070    6    3   8.0   4.4   28.5  83.3    -8.9     50  0.3
  6000   23.2  73.8   065    5    3   2.0   1.1   28.3  82.9    -9.2     28  0.1
  5750   22.8  73.0   070    4    2  -8.0  -4.4   27.2  81.0   -10.2     31  0.2
  5500   22.3  72.1   080    3    2  -0.5  -0.3   26.0  78.9   -11.5     39  0.2
  5250   22.6  72.7   100    2    1   6.0   3.3   25.7  78.2   -12.0     23  0.1
  5000   22.5  72.5   125    2    1 -10.8  -5.9   24.9  76.8   -12.9     20  0.1

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

           07/27/2014 at 0900 MDT          |       07/27/2014 at 1200 MDT
                                           |
K index... +29.5  LI... -1.7               | K index... +26.4  LI... -2.3
CAPE... +156.9  CIN... -177.8              | CAPE... +375.8  CIN... -33.6
                                           |
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 -67.4 -89.3  225   8  4   2.0   1.1 | -67.4 -89.3  205  13  7   2.3   1.2
 45000 -61.7 -79.1  230  18  9   6.4   3.5 | -61.5 -78.7  215  19 10   6.4   3.5
 40000 -51.6 -60.9  225  23 12   8.0   4.4 | -51.4 -60.5  225  20 10   8.0   4.4
 38000 -46.8 -52.2  230  21 11   8.0   4.4 | -46.6 -51.9  225  19 10   8.0   4.4
 36000 -42.0 -43.6  235  19 10   7.9   4.4 | -41.7 -43.1  230  17  9   8.1   4.4
 34000 -37.2 -35.0  230  17  9   7.9   4.3 | -36.3 -33.3  230  16  8   8.1   4.5
 32000 -31.9 -25.4  230  15  8   8.3   4.6 | -31.4 -24.5  230  16  8   8.1   4.5
 30000 -27.5 -17.5  230  17  9   7.4   4.1 | -27.0 -16.6  230  16  8   7.4   4.0
 29000 -25.3 -13.5  230  18  9   7.4   4.1 | -24.9 -12.8  235  17  9   7.3   4.0
 28000 -23.2  -9.8  230  18  9   6.9   3.8 | -22.8  -9.0  235  17  9   6.4   3.5
 27000 -21.1  -6.0  240  18  9   6.9   3.8 | -20.9  -5.6  240  16  8   6.4   3.5
 26000 -19.1  -2.4  245  18  9   6.9   3.8 | -18.9  -2.0  245  16  8   6.4   3.5
 25000 -17.0   1.4  250  19 10   6.5   3.6 | -17.0   1.4  250  16  8   7.2   4.0
 24000 -15.1   4.8  255  20 10   6.5   3.5 | -14.8   5.4  250  16  8   7.4   4.1
 23000 -13.2   8.2  255  21 11   6.5   3.6 | -12.6   9.3  255  17  9   7.4   4.1
 22000 -11.3  11.7  255  21 11   6.1   3.3 | -10.5  13.1  255  18  9   6.1   3.3
 21000  -9.5  14.9  255  23 12   6.0   3.3 |  -8.7  16.3  255  20 10   5.9   3.2
 20000  -7.7  18.1  255  24 12   6.0   3.3 |  -7.0  19.4  255  22 11   5.9   3.2
 19500  -6.8  19.8  250  24 13   6.1   3.3 |  -5.6  21.9  255  23 12   6.2   3.4
 19000  -5.5  22.1  250  25 13   6.4   3.5 |  -4.7  23.5  255  24 12   6.2   3.4
 18500  -4.6  23.7  250  25 13   6.8   3.7 |  -3.8  25.2  255  24 13   6.5   3.6
 18000  -3.5  25.7  245  24 13   7.9   4.3 |  -2.8  27.0  255  24 13   7.6   4.2
 17500  -2.4  27.7  245  23 12   7.9   4.3 |  -1.7  28.9  250  24 12   7.6   4.2
 17000  -1.3  29.7  245  21 11   8.9   4.9 |  -0.7  30.7  250  24 12   7.9   4.4
 16500  -0.0  32.0  245  19 10   9.0   4.9 |   0.5  32.9  250  23 12   8.0   4.4
 16000   1.2  34.2  245  16  8   8.6   4.7 |   1.6  34.9  245  22 11   8.1   4.5
 15500   2.4  36.3  245  13  7   7.9   4.4 |   2.8  37.0  245  19 10   8.3   4.5
 15000   3.5  38.3  245  10  5   8.0   4.4 |   3.9  39.0  240  16  8   8.3   4.6
 14500   4.7  40.5  245   8  4   8.4   4.6 |   5.1  41.2  240  12  6   8.0   4.4
 14000   5.9  42.6  240   5  3   8.3   4.6 |   6.2  43.2  235   9  4   8.0   4.4
 13500   7.1  44.8  225   4  2   8.9   4.9 |   7.4  45.3  225   6  3   8.5   4.7
 13000   8.5  47.3  200   3  1   8.9   4.9 |   8.6  47.5  215   4  2   8.5   4.7
 12500   9.8  49.6  170   3  1   9.1   5.0 |   9.9  49.8  195   3  2   9.0   4.9
 12000  11.1  52.0  140   3  2   9.1   5.0 |  11.2  52.2  185   3  2   9.1   5.0
 11500  12.5  54.5  120   4  2   8.5   4.7 |  12.6  54.7  175   3  2   9.3   5.1
 11000  13.7  56.7  110   5  2   8.2   4.5 |  14.0  57.2  165   3  2   9.4   5.1
 10500  14.9  58.8  100   5  3   6.9   3.8 |  15.2  59.4  155   4  2   4.0   2.2
 10250  15.4  59.7  095   6  3   7.8   4.3 |  15.4  59.7  150   4  2   6.5   3.6
 10000  16.1  61.0  095   6  3   9.4   5.2 |  16.3  61.3  145   4  2  12.2   6.7
  9750  16.8  62.2  095   6  3   9.0   4.9 |  17.1  62.8  140   4  2  10.7   5.9
  9500  17.4  63.3  095   6  3   8.0   4.4 |  17.8  64.0  135   4  2   8.0   4.4
  9250  17.9  64.2  095   6  3   7.2   4.0 |  18.3  64.9  130   4  2   6.3   3.5
  9000  18.5  65.3  095   6  3   8.1   4.4 |  18.8  65.8  130   3  2   8.6   4.7
  8750  19.1  66.4  095   6  3   7.9   4.3 |  19.5  67.1  130   3  2   8.8   4.8
  8500  19.6  67.3  095   5  3   6.0   3.3 |  20.1  68.2  130   3  2   7.9   4.3
  8250  19.9  67.8  100   5  2   5.0   2.7 |  20.6  69.1  130   3  1   7.1   3.9
  8000  20.3  68.5  105   4  2   5.5   3.0 |  21.1  70.0  130   3  1   8.2   4.5
  7750  20.7  69.3  110   3  2   4.7   2.6 |  21.8  71.2  130   3  1   9.3   5.1
  7500  20.9  69.6  120   3  2   3.1   1.7 |  22.4  72.3  130   2  1   9.3   5.1
  7250  21.1  70.0  125   3  2   2.8   1.5 |  23.1  73.6  130   2  1   9.3   5.1
  7000  21.3  70.3  130   3  2   2.4   1.3 |  23.8  74.8  135   2  1   9.8   5.4
  6750  21.5  70.7  140   3  2   4.0   2.2 |  24.5  76.1  135   2  1  10.7   5.9
  6500  21.8  71.2  140   3  2   6.0   3.3 |  25.3  77.5  140   2  1  10.8   5.9
  6250  22.2  72.0  140   3  2   5.5   3.0 |  26.1  79.0  140   2  1  10.7   5.9
  6000  22.5  72.5  145   3  2   6.3   3.5 |  26.9  80.4  145   2  1  10.8   5.9
  5750  23.2  73.8  145   3  2  13.1   7.2 |  27.9  82.2  145   2  1  18.1   9.9
  5500  24.5  76.1  140   3  2  22.0  12.0 |  29.7  85.5  140   2  1  30.0  16.5
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/27/2014 at 1500 MDT          |       07/27/2014 at 1800 MDT
                                           |
K index... +28.1  LI... -1.4               | K index... +27.3  LI... -1.7
CAPE... +181.2  CIN... -37.8               | CAPE... +173.9  CIN... -45.0
                                           |
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 -67.5 -89.5  195  15  8   2.3   1.3 | -67.4 -89.3  215  17  9   1.9   1.0
 45000 -61.3 -78.3  205  22 12   6.5   3.6 | -61.4 -78.5  215  25 13   6.9   3.8
 40000 -51.0 -59.8  205  24 12   8.0   4.4 | -50.8 -59.4  215  27 14   7.8   4.3
 38000 -46.2 -51.2  205  22 11   8.0   4.4 | -46.1 -51.0  215  28 14   7.8   4.3
 36000 -41.4 -42.5  210  20 10   7.9   4.4 | -41.3 -42.3  220  27 14   7.9   4.3
 34000 -36.7 -34.1  215  20 10   7.9   4.3 | -36.6 -33.9  220  25 13   7.9   4.3
 32000 -31.3 -24.3  225  20 10   8.3   4.6 | -31.8 -25.2  225  24 12   8.5   4.6
 30000 -26.8 -16.2  230  20 10   7.5   4.1 | -26.6 -15.9  235  21 11   7.8   4.3
 29000 -24.6 -12.3  235  19 10   7.5   4.1 | -24.3 -11.7  235  20 10   7.8   4.3
 28000 -22.5  -8.5  240  18  9   6.7   3.7 | -22.1  -7.8  240  18  9   6.6   3.6
 27000 -20.5  -4.9  240  16  8   6.7   3.7 | -20.2  -4.4  240  15  8   6.5   3.6
 26000 -18.5  -1.3  245  13  7   6.7   3.7 | -18.2  -0.8  245  12  6   6.6   3.6
 25000 -16.4   2.5  250  12  6   7.2   4.0 | -16.3   2.7  250  10  5   6.7   3.7
 24000 -14.2   6.4  260  13  6   7.2   4.0 | -14.2   6.4  260  10  5   6.8   3.7
 23000 -12.1  10.2  265  14  7   7.2   4.0 | -12.1  10.2  270  10  5   6.8   3.8
 22000 -10.0  14.0  270  15  8   5.8   3.2 | -10.1  13.8  280  10  5   5.7   3.1
 21000  -8.3  17.1  270  17  9   5.8   3.2 |  -8.4  16.9  285  12  6   5.7   3.1
 20000  -6.5  20.3  270  20 10   5.9   3.2 |  -6.7  19.9  290  13  7   5.8   3.2
 19500  -5.7  21.7  270  21 11   6.1   3.4 |  -5.8  21.6  290  14  7   6.3   3.4
 19000  -4.8  23.4  270  22 11   6.4   3.5 |  -4.9  23.2  290  14  7   6.9   3.8
 18500  -3.8  25.2  270  23 12   6.4   3.5 |  -3.9  25.0  290  15  8   6.8   3.7
 18000  -2.9  26.8  270  24 12   7.5   4.1 |  -2.8  27.0  290  15  8   8.1   4.5
 17500  -1.8  28.8  270  24 13   7.6   4.2 |  -1.7  28.9  290  15  8   8.2   4.5
 17000  -0.8  30.6  265  25 13   7.9   4.3 |  -0.5  31.1  285  16  8   8.1   4.5
 16500   0.4  32.7  265  24 12   8.2   4.5 |   0.6  33.1  280  15  8   8.1   4.4
 16000   1.6  34.9  260  23 12   8.3   4.5 |   1.7  35.1  275  15  8   8.1   4.5
 15500   2.7  36.9  260  22 11   8.4   4.6 |   2.9  37.2  275  15  8   8.9   4.9
 15000   4.5  40.1  255  18  9   8.4   4.6 |   4.2  39.6  270  14  7   8.9   4.9
 14500   5.7  42.3  250  15  8   8.2   4.5 |   6.0  42.8  265  12  6   8.5   4.7
 14000   6.9  44.4  245  12  6   8.3   4.5 |   7.2  45.0  260  10  5   8.5   4.7
 13500   8.1  46.6  245  10  5   8.5   4.7 |   8.5  47.3  255   9  4   9.0   4.9
 13000   9.4  48.9  240   8  4   8.5   4.6 |   9.8  49.6  250   7  4   9.0   4.9
 12500  10.6  51.1  235   6  3   8.7   4.8 |  11.1  52.0  240   6  3   9.0   4.9
 12000  11.9  53.4  230   5  3   8.8   4.8 |  12.4  54.3  225   4  2   9.0   5.0
 11500  13.2  55.8  230   4  2   8.5   4.7 |  13.7  56.7  210   4  2   8.8   4.8
 11000  14.4  57.9  220   3  1   9.1   5.0 |  15.0  59.0  190   4  2   9.3   5.1
 10500  15.4  59.7  210   2  1   5.3   2.9 |  16.0  60.8  175   4  2   4.9   2.7
 10250  16.0  60.8  205   2  1  10.0   5.5 |  16.5  61.7  170   4  2   9.3   5.1
 10000  16.8  62.2  205   2  1  11.6   6.4 |  17.3  63.1  170   4  2  10.9   6.0
  9750  17.6  63.7  200   1  1  10.4   5.7 |  18.1  64.6  165   4  2  10.1   5.5
  9500  18.3  64.9  195   1  1   7.6   4.1 |  18.8  65.8  165   5  2   8.0   4.4
  9250  18.8  65.8  195   1  1   8.6   4.7 |  19.3  66.7  165   5  2   8.3   4.5
  9000  19.6  67.3  200   1  1  11.0   6.0 |  20.0  68.0  165   5  2   9.8   5.4
  8750  20.4  68.7  205   1  0  10.3   5.6 |  20.7  69.3  165   5  2   9.3   5.1
  8500  21.1  70.0  210   1  0  10.0   5.5 |  21.4  70.5  165   5  2   8.8   4.8
  8250  21.9  71.4  215   1  0  10.0   5.5 |  22.0  71.6  165   5  2   8.8   4.8
  8000  22.6  72.7  220   1  0  10.3   5.6 |  22.7  72.9  165   5  2   9.9   5.4
  7750  23.4  74.1  225   1  0  10.3   5.7 |  23.5  74.3  165   4  2  10.2   5.6
  7500  24.1  75.4  225   1  0  10.1   5.6 |  24.2  75.6  165   4  2   9.8   5.4
  7250  24.9  76.8  225   1  0  10.2   5.6 |  24.9  76.8  170   4  2   9.8   5.4
  7000  25.7  78.3  225   1  0  10.0   5.5 |  25.7  78.3  170   4  2  10.0   5.5
  6750  26.4  79.5  230   1  0  10.4   5.7 |  26.4  79.5  170   4  2  10.4   5.7
  6500  27.2  81.0  230   1  1  11.0   6.0 |  27.2  81.0  170   4  2  10.5   5.8
  6250  28.0  82.4  235   1  1  10.3   5.7 |  28.0  82.4  175   4  2  10.4   5.7
  6000  28.8  83.8  235   1  1  12.3   6.8 |  28.8  83.8  175   4  2  10.6   5.8
  5750  29.8  85.6  245   1  1  14.8   8.1 |  29.6  85.3  175   4  2  11.6   6.3
  5500  30.9  87.6  255   1  1  14.5   7.9 |  30.5  86.9  175   4  2  12.2   6.7
  5250  32.0  89.6  260   1  1  14.9   8.2 |  31.4  88.5  175   4  2  11.7   6.4
  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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