Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 181237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0636 MDT Thursday, September 18, 2014

This forecast is for Thursday, September 18, 2014:

If the trigger temperature of 80.5 F/26.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1074 ft/min (5.5 m/s)
   Maximum height of thermals.................. 14960 ft MSL (10121 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9818 ft MSL (4979 ft AGL)
Thermal soaring outlook for Friday 09/19....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:58:11 / 19:19:05 MDT
Total possible sunshine........... 12 hr 20 min 53 sec (740 min 53 sec)
Altitude of sun at 13:08:09 MDT... 52.56 degrees

Upper air data from rawinsonde observation taken on 09/18/2014 at 0600 MDT

Freezing level.................. 16021 ft MSL (11182 ft AGL)
Convective condensation level... 16608 ft MSL (11769 ft AGL)
Lifted condensation level....... 15481 ft MSL (10642 ft AGL)
Lifted index.................... -0.5
K index......................... +26.0

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  -69.2 -92.6   270   32   17   4.1   2.2   79.1 174.3    27.8      M    M
 45000  -62.1 -79.8   270   44   22   2.8   1.5   66.4 151.5    22.0      M    M
 40000  -54.6 -66.3   270   43   22   8.0   4.4   55.3 131.5    16.1      M    M
 38000  -49.2 -56.6   270   31   16   7.9   4.3   53.5 128.3    15.4      M    M
 36000  -44.6 -48.3   285   28   14   7.5   4.1   51.6 124.9    14.4      M    M
 34000  -39.7 -39.5   305   26   13   8.7   4.8   50.3 122.5    13.9      M    M
 32000  -34.5 -30.1   305   32   16   8.7   4.8   49.5 121.0    13.6      M    M
 30000  -30.1 -22.2   300   24   12   7.9   4.3   47.5 117.5    12.4      M    M
 29000  -27.8 -18.0   300   23   12   7.7   4.2   46.7 116.1    11.9      M    M
 28000  -25.4 -13.7   310   19   10   7.9   4.3   45.9 114.6    11.5      M    M
 27000  -22.9  -9.2   325   16    8   9.0   5.0   45.4 113.7    11.2      M    M
 26000  -20.4  -4.7   325   15    7   4.9   2.7   44.9 112.8    10.9      M    M
 25000  -19.0  -2.2   320   13    7   7.9   4.3   43.0 109.3     9.5      M    M
 24000  -16.9   1.6   315   13    7   7.0   3.8   42.0 107.6     8.8      M    M
 23000  -15.0   5.0   345    3    1   6.8   3.7   40.8 105.4     7.8      M    M
 22000  -13.0   8.6   130    2    1   0.8   0.5   39.7 103.5     7.0      M    M
 21000  -10.7  12.7   145    6    3   9.7   5.3   38.8 101.9     6.4      M    M
 20000   -8.5  16.7   150   11    6   5.9   3.2   37.1  98.9     5.1      M    M
 19500   -7.4  18.7   140   13    7   8.1   4.5   36.7  98.0     4.7      M    M
 19000   -6.3  20.7   135   14    7   7.7   4.2   36.3  97.4     4.4      M    M
 18500   -5.1  22.8   135   16    8   7.9   4.3   36.0  96.8     4.1      M    M
 18000   -3.8  25.2   130   17    9   8.7   4.8   35.8  96.4     4.0      M    M
 17500   -2.8  27.0   130   16    8   5.9   3.3   35.3  95.5     3.6      M    M
 17000   -1.8  28.8   130   15    8   7.4   4.1   34.8  94.6     3.1      M    M
 16500   -0.7  30.7   130   14    7   8.3   4.6   34.4  94.0     2.8      M    M
 16000    0.1  32.2   130   13    7   2.6   1.4   33.7  92.7     2.1      M    M
 15500    0.1  32.2   135   12    6   4.0   2.2   32.5  90.4     0.7      M    M
 15000    0.9  33.6   145   11    5   7.8   4.3   31.9  89.4    -0.0    873  4.4
 14500    2.2  36.0   150   10    5   8.9   4.9   31.8  89.2    -0.1    818  4.2
 14000    3.6  38.5   160    9    5   9.0   4.9   31.7  89.1    -0.2    763  3.9
 13500    4.9  40.8   150    9    4   9.0   4.9   31.5  88.8    -0.4    709  3.6
 13000    6.2  43.2   140    9    4   9.0   4.9   31.4  88.6    -0.5    654  3.3
 12500    7.6  45.7   135    9    4   9.0   4.9   31.3  88.4    -0.6    599  3.0
 12000    8.9  48.0   125    9    5   9.0   4.9   31.2  88.2    -0.7    544  2.8
 11500   10.2  50.4   125    7    4   8.9   4.9   31.1  87.9    -0.9    490  2.5
 11000   11.6  52.9   130    6    3   7.9   4.3   30.9  87.7    -1.0    435  2.2
 10500   12.3  54.1   135    5    2   4.9   2.7   30.3  86.5    -1.7    397  2.0
 10250   12.7  54.9   145    3    2   4.7   2.6   29.9  85.8    -2.1    380  1.9
 10000   12.9  55.2   200    1    1   4.5   2.5   29.5  85.1    -2.6    364  1.9
  9750   13.2  55.8   240    2    1   4.4   2.4   29.1  84.3    -3.1    349  1.8
  9500   13.5  56.3   250    3    1   5.1   2.8   28.7  83.6    -3.6    334  1.7
  9250   13.9  57.0   255    4    2   7.3   4.0   28.4  83.1    -3.9    313  1.6
  9000   14.5  58.1   260    5    3   8.3   4.5   28.3  82.9    -3.9    286  1.5
  8750   15.2  59.4   245    3    2   8.1   4.4   28.1  82.6    -4.0    259  1.3
  8500   15.9  60.6   205    2    1   8.1   4.4   28.0  82.4    -4.1    232  1.2
  8250   16.4  61.5   155    3    1   8.0   4.4   27.9  82.2    -4.3    207  1.1
  8000   17.0  62.6   130    5    2   8.0   4.4   27.7  81.9    -4.4    182  0.9
  7750   17.6  63.7   130    6    3   7.9   4.3   27.6  81.7    -4.6    158  0.8
  7500   18.2  64.8   135    7    4   8.5   4.6   27.5  81.4    -4.8    133  0.7
  7250   18.8  65.8   135    8    4   6.3   3.4   27.3  81.2    -4.9    108  0.5
  7000   19.0  66.2   135   10    5   1.5   0.8   26.9  80.4    -5.4     93  0.5
  6750   19.1  66.4   135   11    6   0.1   0.1   26.2  79.1    -6.1     84  0.4
  6500   19.1  66.4   140   13    7   0.8   0.5   25.4  77.8    -6.8     75  0.4
  6250   19.2  66.6   140   15    8  -0.5  -0.3   24.7  76.5    -7.5     66  0.3
  6000   19.2  66.6   140   17    9   4.1   2.3   24.0  75.3    -8.2     58  0.3
  5750   19.8  67.6   140   16    8   8.8   4.8   23.9  75.0    -8.4     33  0.2
  5500   20.3  68.5   135   14    7   7.2   4.0   23.7  74.7    -8.6      9  0.0
  5250   20.9  69.6   130   12    6   8.9   4.9   23.6  74.5    -8.7      M    M
  5000   21.1  70.0   120   10    5 -12.7  -7.0   23.0  73.5    -9.3      M    M

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

           09/18/2014 at 0900 MDT          |       09/18/2014 at 1200 MDT
                                           |
K index... +19.7  LI... +1.3               | K index... +14.3  LI... +0.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -67.7 -89.9  275  36 19   2.7   1.5 | -67.3 -89.1  270  34 17   2.7   1.5
 45000 -62.4 -80.3  270  43 22   5.7   3.1 | -62.2 -80.0  270  40 21   5.2   2.9
 40000 -53.6 -64.5  275  33 17   6.9   3.8 | -53.6 -64.5  265  31 16   7.0   3.8
 38000 -49.4 -56.9  275  30 15   6.9   3.8 | -49.4 -56.9  265  28 14   7.0   3.8
 36000 -45.3 -49.5  280  26 14   6.8   3.7 | -45.2 -49.4  260  24 12   7.0   3.8
 34000 -40.4 -40.7  290  23 12   8.4   4.6 | -40.1 -40.2  265  21 11   8.8   4.8
 32000 -34.7 -30.5  300  21 11   8.4   4.6 | -34.8 -30.6  275  19 10   8.7   4.8
 30000 -30.0 -22.0  300  18  9   7.7   4.2 | -29.9 -21.8  280  17  9   8.2   4.5
 29000 -27.7 -17.9  300  17  9   7.7   4.2 | -27.4 -17.3  280  17  9   8.2   4.5
 28000 -25.4 -13.7  305  15  8   7.4   4.1 | -25.0 -13.0  285  16  8   7.9   4.3
 27000 -23.3  -9.9  305  12  6   7.3   4.0 | -22.8  -9.0  280  13  7   7.4   4.1
 26000 -21.1  -6.0  305   9  5   7.3   4.0 | -20.0  -4.0  265   9  4   7.4   4.1
 25000 -18.9  -2.0  310   6  3   7.3   4.0 | -17.8  -0.0  240   6  3   7.1   3.9
 24000 -16.9   1.6  290   2  1   6.5   3.5 | -15.9   3.4  210   6  3   6.3   3.5
 23000 -15.0   5.0  160   3  1   6.5   3.5 | -14.0   6.8  190   8  4   6.3   3.5
 22000 -13.0   8.6  145   7  3   6.5   3.6 | -12.1  10.2  175  11  5   6.3   3.4
 21000 -11.1  12.0  145   8  4   6.6   3.6 | -10.3  13.5  170  11  5   6.2   3.4
 20000  -9.1  15.6  145   8  4   6.6   3.6 |  -8.4  16.9  165  11  5   6.2   3.4
 19500  -8.1  17.4  145   8  4   6.6   3.6 |  -7.5  18.5  165  10  5   6.3   3.4
 19000  -7.1  19.2  145   8  4   6.7   3.7 |  -6.6  20.1  160  10  5   5.9   3.3
 18500  -6.1  21.0  150   8  4   6.7   3.7 |  -5.7  21.7  165  10  5   6.0   3.3
 18000  -5.1  22.8  155   9  4   6.8   3.7 |  -4.8  23.4  165  10  5   6.3   3.4
 17500  -4.2  24.4  160   9  5   6.8   3.8 |  -3.9  25.0  165  10  5   6.7   3.7
 17000  -3.2  26.2  160   9  5   6.9   3.8 |  -2.9  26.8  165  10  5   6.7   3.7
 16500  -2.2  28.0  160   9  5   7.7   4.2 |  -1.9  28.6  170  10  5   7.6   4.2
 16000  -1.1  30.0  160   9  5   7.8   4.3 |  -0.8  30.6  170  10  5   7.6   4.2
 15500   0.6  33.1  160   8  4   8.2   4.5 |   0.3  32.5  170  11  6   8.1   4.4
 15000   1.8  35.2  160   8  4   8.2   4.5 |   1.5  34.7  165  11  6   8.4   4.6
 14500   2.9  37.2  155   7  3   8.0   4.4 |   2.7  36.9  165  11  6   8.5   4.7
 14000   4.1  39.4  160   6  3   7.9   4.3 |   4.0  39.2  165  11  6   8.7   4.8
 13500   5.3  41.5  160   6  3   8.0   4.4 |   5.2  41.4  160  10  5   8.7   4.8
 13000   6.5  43.7  165   6  3   8.2   4.5 |   7.0  44.6  160  10  5   8.0   4.4
 12500   7.7  45.9  165   6  3   8.1   4.4 |   8.1  46.6  160   9  5   7.8   4.3
 12000   8.9  48.0  170   6  3   7.8   4.3 |   9.2  48.6  165   9  5   7.4   4.1
 11500  10.0  50.0  175   5  3   7.7   4.2 |  10.3  50.5  165   9  4   7.5   4.1
 11000  11.0  51.8  180   5  3   6.9   3.8 |  11.4  52.5  170   8  4   7.4   4.1
 10500  12.1  53.8  180   5  3   4.3   2.3 |  12.5  54.5  175   8  4   4.9   2.7
 10250  12.2  54.0  185   5  3   4.4   2.4 |  12.7  54.9  175   8  4   5.2   2.8
 10000  12.8  55.0  185   5  3   8.0   4.4 |  13.3  55.9  175   8  4   8.6   4.7
  9750  13.3  55.9  185   5  3   7.4   4.1 |  13.8  56.8  180   8  4   8.3   4.6
  9500  13.8  56.8  190   5  3   6.4   3.5 |  14.4  57.9  180   8  4   6.4   3.5
  9250  14.2  57.6  190   5  3   4.7   2.6 |  14.7  58.5  180   7  4   4.6   2.5
  9000  14.5  58.1  190   5  3   5.8   3.2 |  15.1  59.2  185   7  3   6.1   3.4
  8750  15.0  59.0  190   5  3   6.6   3.6 |  15.5  59.9  190   6  3   6.5   3.6
  8500  15.4  59.7  195   5  3   5.7   3.1 |  16.0  60.8  190   6  3   6.0   3.3
  8250  15.8  60.4  190   5  3   4.7   2.6 |  16.4  61.5  195   5  3   5.5   3.0
  8000  16.1  61.0  190   5  3   4.4   2.4 |  16.8  62.2  200   5  2   5.6   3.1
  7750  16.4  61.5  185   5  3   4.3   2.3 |  17.1  62.8  200   4  2   5.3   2.9
  7500  16.6  61.9  180   6  3   3.5   1.9 |  17.5  63.5  205   3  2   7.1   3.9
  7250  16.9  62.4  175   6  3   2.9   1.6 |  18.1  64.6  210   3  1   8.5   4.7
  7000  17.1  62.8  170   7  3   2.7   1.5 |  18.7  65.7  215   2  1   8.3   4.6
  6750  17.2  63.0  170   7  3   1.0   0.5 |  19.4  66.9  220   2  1   9.3   5.1
  6500  17.2  63.0  160   7  3  -1.3  -0.7 |  20.1  68.2  225   2  1  10.5   5.7
  6250  17.1  62.8  155   6  3  -1.4  -0.8 |  20.9  69.6  225   2  1  11.2   6.2
  6000  17.0  62.6  145   6  3  -3.6  -2.0 |  21.7  71.1  230   2  1  10.1   5.5
  5750  16.7  62.1  125   5  3   0.2   0.1 |  22.5  72.5  230   2  1  11.5   6.3
  5500  17.1  62.8  120   5  2   6.8   3.7 |  23.4  74.1  230   2  1  14.3   7.8
  5250  17.4  63.3  110   4  2   2.0   1.1 |  24.4  75.9  235   2  1  12.8   7.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/18/2014 at 1500 MDT          |       09/18/2014 at 1800 MDT
                                           |
K index... +16.2  LI... 0.0                | K index... +26.1  LI... -0.4
CAPE... +12.1  CIN... -42.1                | CAPE... +291.6  CIN... -74.2
                                           |
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 -67.7 -89.9  265  37 19   2.8   1.5 | -67.8 -90.0  270  41 21   2.6   1.4
 45000 -62.3 -80.1  265  41 21   5.5   3.0 | -62.2 -80.0  265  45 23   6.3   3.5
 40000 -53.4 -64.1  255  34 18   6.7   3.7 | -52.8 -63.0  260  37 19   5.9   3.2
 38000 -49.4 -56.9  250  30 16   6.7   3.7 | -49.3 -56.7  245  33 17   5.9   3.2
 36000 -45.4 -49.7  240  27 14   6.8   3.7 | -45.7 -50.3  230  31 16   5.7   3.1
 34000 -40.1 -40.2  245  23 12   9.0   4.9 | -40.1 -40.2  230  27 14   8.8   4.8
 32000 -34.7 -30.5  245  19 10   9.0   4.9 | -34.8 -30.6  230  23 12   9.1   5.0
 30000 -29.7 -21.5  255  16  8   8.4   4.6 | -29.7 -21.5  235  17  9   8.5   4.6
 29000 -27.1 -16.8  265  14  7   8.4   4.6 | -27.1 -16.8  235  14  7   8.5   4.6
 28000 -24.6 -12.3  275  13  7   8.0   4.4 | -24.6 -12.3  240  12  6   7.9   4.3
 27000 -22.4  -8.3  265  12  6   7.6   4.2 | -22.3  -8.1  235  13  7   7.7   4.2
 26000 -19.5  -3.1  250  10  5   7.6   4.2 | -20.0  -4.0  235  14  7   7.7   4.2
 25000 -17.3   0.9  235  10  5   7.3   4.0 | -17.7   0.1  230  15  8   7.7   4.2
 24000 -15.2   4.6  220  10  5   6.7   3.7 | -15.4   4.3  230  16  8   7.6   4.2
 23000 -13.2   8.2  205  11  6   6.7   3.7 | -13.1   8.4  225  16  8   7.6   4.2
 22000 -11.2  11.8  195  13  6   6.4   3.5 | -10.8  12.6  220  16  8   7.4   4.1
 21000  -9.5  14.9  190  13  7   5.9   3.2 |  -8.9  16.0  210  16  8   6.2   3.4
 20000  -7.7  18.1  180  14  7   5.9   3.2 |  -7.1  19.2  200  17  9   6.2   3.4
 19500  -6.8  19.8  180  15  8   5.9   3.2 |  -6.2  20.8  195  17  9   6.3   3.5
 19000  -6.0  21.2  175  15  8   5.6   3.1 |  -5.3  22.5  190  18  9   5.4   2.9
 18500  -5.2  22.6  175  14  7   5.7   3.1 |  -4.6  23.7  190  17  9   5.3   2.9
 18000  -4.3  24.3  175  14  7   6.1   3.3 |  -3.8  25.2  185  16  8   5.5   3.0
 17500  -3.4  25.9  180  13  7   6.8   3.7 |  -2.9  26.8  185  15  8   6.7   3.7
 17000  -2.4  27.7  180  12  6   6.7   3.7 |  -2.0  28.4  185  14  7   6.7   3.7
 16500  -1.4  29.5  180  12  6   7.8   4.3 |  -1.0  30.2  190  13  7   7.1   3.9
 16000  -0.2  31.6  180  12  6   7.8   4.3 |  -0.0  32.0  190  13  6   7.3   4.0
 15500   0.9  33.6  185  11  6   8.1   4.5 |   1.5  34.7  190  11  6   7.7   4.2
 15000   2.0  35.6  185  11  6   8.3   4.6 |   2.5  36.5  190  10  5   7.8   4.3
 14500   3.2  37.8  185  11  6   8.4   4.6 |   3.6  38.5  195   9  5   8.7   4.8
 14000   4.4  39.9  180  11  6   8.3   4.6 |   4.9  40.8  195   8  4   9.2   5.0
 13500   5.6  42.1  180  11  6   8.4   4.6 |   6.2  43.2  195   7  4   9.0   4.9
 13000   7.4  45.3  180  10  5   8.6   4.7 |   7.5  45.5  200   6  3   8.6   4.7
 12500   8.7  47.7  175  10  5   8.6   4.7 |   8.8  47.8  205   6  3   8.6   4.7
 12000   9.9  49.8  180  10  5   8.4   4.6 |  10.0  50.0  210   5  3   8.1   4.4
 11500  11.1  52.0  180   9  5   8.1   4.5 |  11.2  52.2  215   5  3   8.1   4.4
 11000  12.2  54.0  185   9  5   7.2   3.9 |  12.3  54.1  220   5  2   7.3   4.0
 10500  13.2  55.8  185   8  4  10.2   5.6 |  13.4  56.1  225   4  2   9.7   5.3
 10250  14.1  57.4  190   8  4  10.7   5.8 |  14.2  57.6  230   4  2  10.4   5.7
 10000  14.6  58.3  195   7  4   6.8   3.8 |  14.9  58.8  235   4  2   7.6   4.2
  9750  15.2  59.4  195   7  3   8.0   4.4 |  15.5  59.9  240   4  2   8.4   4.6
  9500  15.7  60.3  200   6  3   7.1   3.9 |  16.1  61.0  245   4  2   8.2   4.5
  9250  16.2  61.2  205   6  3   6.7   3.7 |  16.7  62.1  245   4  2   8.1   4.5
  9000  16.7  62.1  215   5  2   7.0   3.8 |  17.3  63.1  250   4  2   7.9   4.3
  8750  17.2  63.0  225   4  2   7.1   3.9 |  17.9  64.2  255   4  2   7.9   4.4
  8500  17.7  63.9  240   4  2   6.7   3.7 |  18.5  65.3  255   4  2   8.0   4.4
  8250  18.1  64.6  255   4  2   5.9   3.3 |  19.1  66.4  260   4  2   7.9   4.3
  8000  18.5  65.3  270   4  2   6.5   3.6 |  19.6  67.3  265   4  2   7.0   3.8
  7750  19.0  66.2  275   4  2   6.1   3.4 |  20.1  68.2  270   4  2   6.4   3.5
  7500  19.4  66.9  285   4  2   8.6   4.7 |  20.6  69.1  275   4  2   6.7   3.7
  7250  20.2  68.4  285   4  2  11.6   6.4 |  21.1  70.0  275   4  2   6.8   3.8
  7000  21.0  69.8  285   4  2  10.2   5.6 |  21.6  70.9  275   4  2   7.5   4.1
  6750  21.7  71.1  285   4  2   9.4   5.2 |  22.2  72.0  275   4  2   7.6   4.2
  6500  22.5  72.5  285   4  2  10.5   5.7 |  22.7  72.9  275   4  2   9.2   5.1
  6250  23.3  73.9  285   4  2  11.4   6.3 |  23.5  74.3  275   4  2  10.9   6.0
  6000  24.1  75.4  285   4  2  10.3   5.6 |  24.3  75.7  270   4  2  10.3   5.7
  5750  24.9  76.8  285   4  2  11.1   6.1 |  25.0  77.0  270   4  2   9.4   5.1
  5500  25.8  78.4  285   4  2  14.0   7.7 |  25.6  78.1  270   4  2   7.8   4.3
  5250  26.8  80.2  285   5  2  14.2   7.8 |  26.2  79.2  270   4  2   7.2   4.0
  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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