Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 301237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Wednesday, July 30, 2014

This forecast is for Wednesday, July 30, 2014:

If the trigger temperature of 76.1 F/24.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 663 ft/min (3.4 m/s)
   Maximum height of thermals.................. 14466 ft MSL (9627 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11820 ft MSL (6980 ft AGL)
Thermal soaring outlook for Thursday 07/31..... Good

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

Remarks...

Sunrise/Sunset.................... 06:12:55 / 20:28:29 MDT
Total possible sunshine........... 14 hr 15 min 34 sec (855 min 34 sec)
Altitude of sun at 13:20:29 MDT... 69.24 degrees

Upper air data from rawinsonde observation taken on 07/30/2014 at 0600 MDT

Freezing level.................. 15462 ft MSL (10623 ft AGL)
Convective condensation level... 12396 ft MSL (7557 ft AGL)
Lifted condensation level....... 13317 ft MSL (8478 ft AGL)
Lifted index.................... -1.4
K index......................... +25.0

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  -66.8 -88.2   275    9    5   6.5   3.6   83.0 181.4    30.4      M    M
 45000  -59.7 -75.5   290   27   14   5.2   2.8   70.4 158.7    24.7      M    M
 40000  -53.3 -63.9   270   51   26   8.3   4.5   56.6 133.9    17.4      M    M
 38000  -49.6 -57.3   290   40   21   8.0   4.4   53.5 128.3    15.7      M    M
 36000  -44.5 -48.1   290   47   24   9.3   5.1   52.4 126.4    15.4      M    M
 34000  -39.0 -38.2   290   48   25   9.1   5.0   51.9 125.4    15.4      M    M
 32000  -33.7 -28.7   290   48   25   7.3   4.0   51.1 124.0    15.2      M    M
 30000  -28.5 -19.3   285   42   22   8.0   4.4   49.4 120.9    14.3      M    M
 29000  -26.1 -15.0   285   40   20   7.7   4.2   48.7 119.6    13.9      M    M
 28000  -23.6 -10.5   290   37   19   8.7   4.8   48.2 118.7    13.6      M    M
 27000  -21.0  -5.8   290   35   18   8.1   4.4   47.8 118.0    13.5      M    M
 26000  -18.8  -1.8   295   32   17   9.5   5.2   46.8 116.3    12.9      M    M
 25000  -16.6   2.1   300   30   15   7.5   4.1   46.0 114.9    12.3      M    M
 24000  -14.3   6.3   310   27   14   7.0   3.9   45.3 113.5    11.8      M    M
 23000  -12.7   9.1   305   22   11   4.6   2.5   43.9 110.9    10.7      M    M
 22000  -11.6  11.1   295   17    9   2.5   1.4   41.7 107.0     8.9      M    M
 21000  -10.2  13.6   275   13    7   5.5   3.0   40.0 104.0     7.6      M    M
 20000   -9.0  15.8   275   14    7   5.9   3.2   38.0 100.5     5.9      M    M
 19500   -7.9  17.8   270   17    9   9.5   5.2   37.6  99.7     5.5      M    M
 19000   -7.1  19.2   270   18    9   3.4   1.9   36.9  98.4     4.9      M    M
 18500   -6.2  20.8   270   17    9   7.1   3.9   36.3  97.3     4.3      M    M
 18000   -5.1  22.8   275   16    8   7.2   3.9   35.8  96.5     3.9      M    M
 17500   -4.1  24.6   275   15    8   7.2   3.9   35.4  95.6     3.5      M    M
 17000   -3.0  26.6   275   14    7   7.2   3.9   34.9  94.9     3.2      M    M
 16500   -1.5  29.3   280   12    6   6.7   3.7   34.4  93.8     2.6      M    M
 16000   -0.7  30.7   280   11    5   5.3   2.9   33.7  92.6     2.0      M    M
 15500    0.1  32.2   275    9    5   5.4   2.9   32.9  91.2     1.3      M    M
 15000    0.9  33.6   275    8    4   5.4   2.9   32.2  89.9     0.6      M    M
 14500    1.6  34.9   265    6    3   5.4   3.0   31.5  88.6    -0.1    759  3.9
 14000    2.4  36.3   260    5    3   5.3   2.9   30.8  87.4    -0.7    721  3.7
 13500    3.2  37.8   260    6    3   7.5   4.1   30.1  86.3    -1.3    681  3.5
 13000    4.5  40.1   255    6    3   8.1   4.5   29.9  85.8    -1.6    630  3.2
 12500    5.7  42.3   255    7    3   8.5   4.7   29.6  85.3    -1.9    579  2.9
 12000    6.3  43.3   255    7    4   1.6   0.9   28.8  83.9    -2.6    544  2.8
 11500    6.6  43.9   255    6    3   3.9   2.1   27.6  81.7    -3.9    523  2.7
 11000    7.6  45.7   250    6    3   8.7   4.8   27.3  81.1    -4.3    476  2.4
 10500    8.9  48.0   250    5    3   8.6   4.7   27.1  80.7    -4.5    424  2.2
 10250    9.5  49.1   245    5    3   8.4   4.6   27.0  80.6    -4.6    398  2.0
 10000   10.1  50.2   235    5    3   8.5   4.6   26.9  80.4    -4.8    372  1.9
  9750   10.7  51.3   225    5    3   8.3   4.5   26.8  80.2    -4.9    346  1.8
  9500   11.4  52.5   220    5    3   9.0   4.9   26.7  80.0    -5.0    320  1.6
  9250   12.0  53.6   210    6    3   6.5   3.5   26.6  79.8    -5.1    294  1.5
  9000   12.3  54.1   205    6    3   3.9   2.1   26.2  79.1    -5.5    277  1.4
  8750   12.6  54.7   195    7    4   4.3   2.4   25.7  78.3    -6.0    260  1.3
  8500   12.9  55.2   185    8    4   4.7   2.6   25.3  77.6    -6.4    244  1.2
  8250   13.2  55.8   180    9    5   2.5   1.4   24.9  76.8    -6.8    228  1.2
  8000   13.2  55.8   175   11    6   0.4   0.2   24.2  75.6    -7.6    220  1.1
  7750   13.2  55.8   170   10    5   1.2   0.7   23.5  74.3    -8.3    213  1.1
  7500   13.2  55.8   160    9    5   0.2   0.1   22.8  73.1    -9.1    206  1.0
  7250   13.2  55.8   155    9    4   3.7   2.0   22.2  71.9    -9.8    198  1.0
  7000   13.7  56.7   140    8    4   8.3   4.6   21.9  71.5   -10.1    177  0.9
  6750   14.3  57.7   130    7    3   8.2   4.5   21.8  71.3   -10.3    152  0.8
  6500   14.9  58.8   115    5    3   8.3   4.6   21.7  71.1   -10.4    126  0.6
  6250   15.4  59.7   090    5    2   8.1   4.4   21.6  70.9   -10.6    101  0.5
  6000   16.0  60.8   065    5    2   9.1   5.0   21.5  70.7   -10.7     76  0.4
  5750   16.6  61.9   060    4    2   4.7   2.6   21.4  70.5   -10.9     52  0.3
  5500   16.7  62.1   070    2    1   0.5   0.3   20.7  69.3   -11.6     43  0.2
  5250   16.7  62.1   090    1    1   1.9   1.0   20.1  68.2   -12.3     33  0.2
  5000   16.8  62.2   185    1    0   0.6   0.3   19.5  67.1   -13.0     24  0.1

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

           07/30/2014 at 0900 MDT          |       07/30/2014 at 1200 MDT
                                           |
K index... +28.0  LI... -0.9               | K index... +26.4  LI... -1.8
CAPE... +40.0  CIN... -36.3                | CAPE... +296.2  CIN... -7.6
                                           |
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 -63.0 -81.4  295  10  5   2.8   1.6 | -63.2 -81.8  295  15  8   2.9   1.6
 45000 -58.9 -74.0  290  23 12   2.4   1.3 | -59.1 -74.4  290  31 16   2.0   1.1
 40000 -53.7 -64.7  295  43 22   8.4   4.6 | -54.4 -65.9  285  47 24   9.6   5.2
 38000 -48.7 -55.7  295  46 24   8.4   4.6 | -48.7 -55.7  290  47 24   9.5   5.2
 36000 -43.6 -46.5  300  50 26   8.4   4.6 | -43.0 -45.4  290  46 24   9.1   5.0
 34000 -38.6 -37.5  300  46 24   8.4   4.6 | -38.2 -36.8  290  41 21   8.0   4.4
 32000 -33.5 -28.3  300  42 22   8.7   4.8 | -32.8 -27.0  295  35 18   8.3   4.5
 30000 -28.7 -19.7  300  41 21   8.0   4.4 | -28.1 -18.6  295  33 17   7.8   4.3
 29000 -26.2 -15.2  300  41 21   8.0   4.4 | -25.8 -14.4  295  32 16   7.8   4.3
 28000 -23.8 -10.8  295  40 21   8.1   4.4 | -23.4 -10.1  295  31 16   8.2   4.5
 27000 -21.4  -6.5  295  39 20   8.1   4.4 | -21.0  -5.8  295  31 16   8.1   4.5
 26000 -19.0  -2.2  295  37 19   8.1   4.4 | -18.6  -1.5  295  31 16   8.1   4.5
 25000 -16.5   2.3  295  36 18   7.9   4.3 | -16.1   3.0  295  31 16   7.3   4.0
 24000 -14.7   5.5  295  33 17   6.0   3.3 | -14.3   6.3  295  28 15   6.0   3.3
 23000 -12.9   8.8  295  30 15   6.1   3.4 | -12.6   9.3  295  26 13   6.1   3.4
 22000 -10.7  12.7  300  26 13   5.7   3.1 | -10.8  12.6  295  23 12   6.1   3.3
 21000  -9.2  15.4  295  24 12   5.5   3.0 |  -9.2  15.4  295  22 11   5.9   3.3
 20000  -7.6  18.3  295  22 11   5.6   3.1 |  -7.5  18.5  295  21 11   6.1   3.3
 19500  -6.8  19.8  290  21 11   5.6   3.1 |  -6.7  19.9  295  20 11   6.1   3.4
 19000  -6.0  21.2  290  20 10   5.5   3.0 |  -5.8  21.6  295  20 10   6.2   3.4
 18500  -5.3  22.5  285  18  9   5.5   3.0 |  -4.9  23.2  290  19 10   6.2   3.4
 18000  -4.4  24.1  285  17  9   6.0   3.3 |  -3.6  25.5  290  18  9   5.8   3.2
 17500  -3.6  25.5  280  17  8   6.1   3.3 |  -2.8  27.0  290  17  9   5.8   3.2
 17000  -2.7  27.1  280  16  8   6.0   3.3 |  -2.0  28.4  285  17  9   5.5   3.0
 16500  -1.9  28.6  275  15  8   5.6   3.1 |  -1.2  29.8  285  16  8   5.2   2.9
 16000  -1.0  30.2  275  15  7   5.6   3.1 |  -0.4  31.3  285  16  8   5.2   2.8
 15500  -0.2  31.6  270  14  7   5.8   3.2 |   0.4  32.7  280  16  8   6.0   3.3
 15000   0.6  33.1  270  14  7   5.8   3.2 |   1.2  34.2  280  15  8   5.9   3.3
 14500   1.4  34.5  270  13  7   6.1   3.4 |   2.0  35.6  280  15  8   5.9   3.2
 14000   2.3  36.1  265  13  7   6.3   3.5 |   2.9  37.2  275  14  7   5.9   3.2
 13500   3.2  37.8  265  13  7   6.2   3.4 |   3.7  38.7  275  14  7   6.2   3.4
 13000   4.1  39.4  265  13  7   6.1   3.3 |   4.6  40.3  270  14  7   6.4   3.5
 12500   4.9  40.8  260  13  7   6.3   3.5 |   5.5  41.9  270  13  7   6.4   3.5
 12000   5.8  42.4  260  12  6   6.8   3.7 |   6.4  43.5  265  13  7   6.4   3.5
 11500   6.8  44.2  260  11  6   6.9   3.8 |   7.3  45.1  260  13  7   6.5   3.6
 11000   7.8  46.0  255  10  5   7.0   3.9 |   8.3  46.9  260  12  6   6.4   3.5
 10500   8.8  47.8  250   8  4   4.9   2.7 |   9.2  48.6  255  11  6   3.9   2.1
 10250   9.0  48.2  245   7  4   4.2   2.3 |   9.4  48.9  255  11  6   4.1   2.3
 10000   9.5  49.1  240   6  3   8.8   4.8 |   9.9  49.8  255  10  5   8.5   4.7
  9750  10.2  50.4  230   5  3  10.3   5.6 |  10.4  50.7  255   9  5   8.4   4.6
  9500  10.9  51.6  220   5  2   8.5   4.6 |  11.0  51.8  250   8  4   7.5   4.1
  9250  11.4  52.5  210   5  2   5.7   3.1 |  11.5  52.7  250   7  4   6.0   3.3
  9000  11.8  53.2  205   5  2   6.5   3.6 |  11.9  53.4  250   6  3   7.4   4.1
  8750  12.4  54.3  200   5  2   8.2   4.5 |  12.5  54.5  250   5  2   8.3   4.6
  8500  13.0  55.4  200   5  2   6.2   3.4 |  13.1  55.6  250   4  2   8.2   4.5
  8250  13.3  55.9  190   4  2   4.4   2.4 |  13.6  56.5  250   3  2   8.2   4.5
  8000  13.7  56.7  180   4  2   4.5   2.5 |  14.2  57.6  245   2  1   8.6   4.7
  7750  14.0  57.2  160   3  2   4.1   2.3 |  14.8  58.6  245   2  1   9.4   5.1
  7500  14.3  57.7  140   3  2   5.3   2.9 |  15.5  59.9  245   2  1   9.8   5.4
  7250  14.7  58.5  130   3  2   6.3   3.5 |  16.3  61.3  250   2  1  10.0   5.5
  7000  15.2  59.4  120   3  2   6.0   3.3 |  17.0  62.6  250   2  1   9.9   5.4
  6750  15.6  60.1  115   3  2   6.3   3.4 |  17.7  63.9  250   2  1  10.0   5.5
  6500  16.1  61.0  110   3  2   7.0   3.8 |  18.5  65.3  255   2  1  10.5   5.8
  6250  16.6  61.9  105   3  2   7.1   3.9 |  19.3  66.7  255   2  1  10.4   5.7
  6000  17.1  62.8  100   3  2   7.4   4.1 |  20.0  68.0  255   2  1  11.2   6.1
  5750  17.7  63.9  090   3  2  12.8   7.0 |  21.0  69.8  255   2  1  17.2   9.4
  5500  18.9  66.0  090   3  2  20.4  11.2 |  22.6  72.7  260   2  1  24.4  13.4
  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

           07/30/2014 at 1500 MDT          |       07/30/2014 at 1800 MDT
                                           |
K index... +24.4  LI... -1.6               | K index... +24.4  LI... -1.3
CAPE... +257.1  CIN... -17.7               | CAPE... +256.6  CIN... -28.2
                                           |
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 -63.6 -82.5  310  22 11   2.6   1.4 | -64.8 -84.6  305  19 10   2.6   1.4
 45000 -59.1 -74.4  290  40 20   3.4   1.9 | -59.9 -75.8  290  38 19   4.1   2.3
 40000 -52.9 -63.2  275  47 24   8.0   4.4 | -52.8 -63.0  275  49 25   7.9   4.3
 38000 -48.1 -54.6  275  45 23   7.9   4.4 | -48.0 -54.4  275  44 23   7.9   4.3
 36000 -43.4 -46.1  275  42 22   8.1   4.4 | -43.3 -45.9  275  40 20   8.1   4.4
 34000 -38.4 -37.1  275  37 19   8.4   4.6 | -38.3 -36.9  275  36 19   8.4   4.6
 32000 -32.7 -26.9  280  31 16   8.8   4.9 | -33.2 -27.8  275  33 17   9.3   5.1
 30000 -28.0 -18.4  285  30 15   8.0   4.4 | -28.4 -19.1  280  29 15   7.9   4.3
 29000 -25.6 -14.1  285  29 15   8.0   4.4 | -25.5 -13.9  280  27 14   7.9   4.4
 28000 -23.3  -9.9  290  29 15   7.7   4.2 | -23.2  -9.8  285  26 13   7.1   3.9
 27000 -21.0  -5.8  290  28 14   7.7   4.2 | -21.1  -6.0  285  25 13   7.1   3.9
 26000 -18.7  -1.7  290  28 14   7.7   4.2 | -19.0  -2.2  285  24 13   7.1   3.9
 25000 -16.4   2.5  290  27 14   7.2   4.0 | -16.9   1.6  285  24 12   7.1   3.9
 24000 -14.4   6.1  290  25 13   6.6   3.6 | -14.8   5.4  290  22 11   7.1   3.9
 23000 -12.5   9.5  290  24 12   6.6   3.6 | -12.7   9.1  290  21 11   7.1   3.9
 22000 -10.6  12.9  290  22 11   6.3   3.5 | -10.6  12.9  295  19 10   6.7   3.7
 21000  -8.9  16.0  295  21 11   6.0   3.3 |  -8.8  16.2  295  18  9   6.4   3.5
 20000  -7.2  19.0  295  19 10   6.1   3.3 |  -6.9  19.6  295  16  8   6.4   3.5
 19500  -6.3  20.7  295  18  9   6.2   3.4 |  -6.0  21.2  295  16  8   6.4   3.5
 19000  -5.5  22.1  290  17  9   5.6   3.1 |  -5.2  22.6  295  15  8   5.3   2.9
 18500  -4.3  24.3  290  16  8   5.7   3.1 |  -4.4  24.1  295  14  7   5.4   2.9
 18000  -3.5  25.7  290  15  8   6.1   3.3 |  -3.6  25.5  295  14  7   5.1   2.8
 17500  -2.6  27.3  290  15  8   6.0   3.3 |  -2.9  26.8  290  14  7   5.0   2.7
 17000  -1.7  28.9  290  14  7   5.4   2.9 |  -2.1  28.2  290  13  7   5.0   2.7
 16500  -1.0  30.2  290  14  7   4.5   2.5 |  -1.3  29.7  290  13  7   6.1   3.4
 16000  -0.3  31.5  285  14  7   4.5   2.5 |  -0.4  31.3  290  13  7   6.0   3.3
 15500   0.5  32.9  285  14  7   6.9   3.8 |   0.5  32.9  290  14  7   6.9   3.8
 15000   1.5  34.7  285  14  7   6.7   3.7 |   1.5  34.7  290  13  7   7.0   3.9
 14500   2.4  36.3  280  14  7   6.5   3.6 |   2.5  36.5  290  13  7   6.9   3.8
 14000   3.3  37.9  280  14  7   6.5   3.6 |   3.9  39.0  290  13  7   6.6   3.6
 13500   4.3  39.7  280  14  7   6.4   3.5 |   4.9  40.8  295  12  6   6.8   3.7
 13000   5.2  41.4  280  14  7   6.4   3.5 |   5.9  42.6  295  12  6   6.8   3.7
 12500   6.1  43.0  275  14  7   6.6   3.6 |   6.8  44.2  300  11  6   6.7   3.7
 12000   7.1  44.8  275  14  7   6.8   3.7 |   7.8  46.0  300  10  5   6.7   3.7
 11500   8.0  46.4  270  14  7   6.8   3.7 |   8.8  47.8  305   9  5   6.9   3.8
 11000   9.0  48.2  270  14  7   6.6   3.6 |   9.8  49.6  305   8  4   6.9   3.8
 10500  10.0  50.0  270  14  7   4.3   2.4 |  10.8  51.4  305   7  4   3.6   2.0
 10250  10.2  50.4  270  14  7   4.5   2.4 |  10.9  51.6  310   7  4   4.7   2.6
 10000  10.6  51.1  270  13  7   8.1   4.4 |  11.5  52.7  310   7  3   9.5   5.2
  9750  11.2  52.2  270  11  6   8.1   4.4 |  12.1  53.8  310   6  3   8.4   4.6
  9500  11.7  53.1  270  10  5   6.4   3.5 |  12.7  54.9  315   5  3   6.8   3.7
  9250  12.0  53.6  275   9  5   4.1   2.3 |  13.0  55.4  315   5  2   5.8   3.2
  9000  12.3  54.1  280   7  4   6.7   3.7 |  13.5  56.3  325   4  2   7.4   4.1
  8750  12.9  55.2  280   6  3   8.3   4.6 |  13.9  57.0  340   4  2   7.6   4.2
  8500  13.4  56.1  290   5  3   8.3   4.5 |  14.4  57.9  350   3  2   7.8   4.3
  8250  14.0  57.2  290   5  3   8.5   4.6 |  15.0  59.0  350   3  2   7.8   4.3
  8000  14.6  58.3  290   5  2   9.3   5.1 |  15.5  59.9  355   3  2   9.3   5.1
  7750  15.3  59.5  290   4  2  10.5   5.8 |  16.3  61.3  355   3  2  10.5   5.7
  7500  16.1  61.0  290   4  2  10.0   5.5 |  17.0  62.6  355   3  2   9.8   5.4
  7250  16.8  62.2  290   4  2   9.5   5.2 |  17.8  64.0  355   3  2   9.7   5.3
  7000  17.5  63.5  290   4  2   9.9   5.4 |  18.5  65.3  355   3  2   9.9   5.4
  6750  18.3  64.9  290   4  2  10.6   5.8 |  19.2  66.6  355   3  2  10.4   5.7
  6500  19.1  66.4  290   4  2  10.7   5.9 |  20.0  68.0  355   3  1  10.7   5.8
  6250  19.8  67.6  290   4  2  10.3   5.7 |  20.8  69.4  355   3  1  10.6   5.8
  6000  20.6  69.1  290   4  2  10.8   5.9 |  21.6  70.9  350   3  1  10.5   5.8
  5750  21.5  70.7  290   4  2  15.8   8.7 |  22.4  72.3  355   3  1  10.7   5.9
  5500  23.0  73.4  290   4  2  22.9  12.6 |  23.2  73.8  355   3  1  11.1   6.1
  5250     M     M    M   M  M     M     M |  24.0  75.2  355   3  1  10.8   5.9
  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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