Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 181929
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
1329 MDT Monday, August 18, 2014

This forecast is for Monday, August 18, 2014:

If the trigger temperature of 87.5 F/30.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1607 ft/min (8.2 m/s)
   Maximum height of thermals.................. 20962 ft MSL (16123 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1100 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................. 9004 ft MSL (4164 ft AGL)
Thermal soaring outlook for Tuesday 08/19...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:30:07 / 20:06:17 MDT
Total possible sunshine........... 13 hr 36 min 10 sec (816 min 10 sec)
Altitude of sun at 13:17:50 MDT... 63.80 degrees

Upper air data from rawinsonde observation taken on 08/18/2014 at 0600 MDT

Freezing level.................. 15956 ft MSL (11117 ft AGL)
Convective condensation level... 17177 ft MSL (12338 ft AGL)
Lifted condensation level....... 17678 ft MSL (12838 ft AGL)
Lifted index.................... -1.4
K index......................... +22.5

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  -63.4 -82.1   285   29   15 -10.3  -5.7   88.6 191.5    31.4      M    M
 45000  -60.0 -76.0   275   43   22   2.0   1.1   69.9 157.9    22.1      M    M
 40000  -53.5 -64.3   275   46   23   4.6   2.5   57.2 135.0    15.2      M    M
 38000  -49.1 -56.4   275   44   23   7.4   4.1   54.9 130.8    14.0      M    M
 36000  -46.0 -50.8   280   42   22   6.4   3.5   49.9 121.9    10.9      M    M
 34000  -42.8 -45.0   280   39   20   9.0   4.9   46.2 115.1     8.5      M    M
 32000  -37.3 -35.1   280   36   19   9.2   5.0   45.8 114.4     8.4      M    M
 30000  -32.1 -25.8   285   28   14   8.3   4.5   45.0 112.9     8.0      M    M
 29000  -29.6 -21.3   285   28   14   8.3   4.5   44.1 111.4     7.4      M    M
 28000  -27.1 -16.8   285   28   14   8.3   4.5   43.5 110.2     7.0      M    M
 27000  -24.7 -12.5   285   27   14   8.3   4.5   42.9 109.2     6.7      M    M
 26000  -22.2  -8.0   285   27   14   8.3   4.5   42.5 108.4     6.4      M    M
 25000  -19.7  -3.5   285   27   14   8.4   4.6   42.1 107.7     6.1      M    M
 24000  -17.5   0.5   285   24   12   7.6   4.2   41.2 106.2     5.4      M    M
 23000  -15.5   4.1   285   22   11   3.2   1.8   40.2 104.4     4.6      M    M
 22000  -15.4   4.3   290   20   10   9.9   5.4   36.9  98.4     1.7      M    M
 21000  -13.9   7.0   290   17    9   3.8   2.1   35.2  95.4     0.3      M    M
 20000  -11.8  10.8   270   10    5   9.1   5.0   34.3  93.8    -0.5   1522  7.7
 19500   -9.8  14.4   260   10    5   9.5   5.2   34.2  93.5    -0.7   1438  7.3
 19000   -8.3  17.1   265    8    4  10.0   5.5   34.2  93.5    -0.6   1379  7.0
 18500   -6.9  19.6   260    8    4   9.3   5.1   34.2  93.5    -0.7   1322  6.7
 18000   -5.5  22.1   260    8    4   9.5   5.2   34.1  93.4    -0.8   1267  6.4
 17500   -4.2  24.4   255    7    4   9.4   5.2   34.1  93.3    -0.9   1211  6.2
 17000   -2.7  27.1   250    7    4   9.4   5.2   34.0  93.2    -1.0   1154  5.9
 16500   -1.3  29.7   250    7    4   9.4   5.1   34.0  93.1    -1.0   1097  5.6
 16000    0.1  32.2   245    7    4   9.4   5.1   33.9  93.0    -1.1   1040  5.3
 15500    1.5  34.7   245    8    4   9.4   5.1   33.8  92.9    -1.1    983  5.0
 15000    2.9  37.2   240    8    4   9.4   5.1   33.8  92.8    -1.2    926  4.7
 14500    4.3  39.7   240    9    4   9.4   5.1   33.7  92.7    -1.2    869  4.4
 14000    5.7  42.3   240    9    5   9.4   5.1   33.7  92.7    -1.3    813  4.1
 13500    7.1  44.8   240   10    5   9.4   5.1   33.6  92.5    -1.4    756  3.8
 13000    8.5  47.3   245   10    5   9.4   5.1   33.5  92.3    -1.5    699  3.6
 12500    9.9  49.8   245   11    5   9.4   5.1   33.5  92.2    -1.6    642  3.3
 12000   11.3  52.3   245   11    6   9.4   5.1   33.4  92.1    -1.6    585  3.0
 11500   12.6  54.7   240   11    6   9.4   5.2   33.3  92.0    -1.7    530  2.7
 11000   14.0  57.2   230   11    6   9.4   5.2   33.3  91.9    -1.9    474  2.4
 10500   15.3  59.5   225   12    6   9.2   5.1   33.3  91.9    -2.0    419  2.1
 10250   16.0  60.8   220   12    6   8.5   4.7   33.2  91.7    -2.1    393  2.0
 10000   16.6  61.9   215   11    6   8.4   4.6   33.1  91.5    -2.2    367  1.9
  9750   17.2  63.0   210   11    5   8.4   4.6   33.0  91.3    -2.3    341  1.7
  9500   17.8  64.0   205   10    5   8.6   4.7   32.9  91.2    -2.5    315  1.6
  9250   18.4  65.1   200   10    5   7.7   4.2   32.8  91.0    -2.6    290  1.5
  9000   18.8  65.8   190   10    5   1.2   0.6   32.4  90.3    -2.9    271  1.4
  8750   18.8  65.8   180   10    5   2.7   1.5   31.6  89.0    -3.7    263  1.3
  8500   19.3  66.7   170   11    6   7.1   3.9   31.4  88.5    -3.9    242  1.2
  8250   19.7  67.5   160   12    6   7.5   4.1   31.1  88.0    -4.2    221  1.1
  8000   20.2  68.4   150   14    7   1.8   1.0   30.9  87.6    -4.5    200  1.0
  7750   19.9  67.8   145   12    6  -7.1  -3.9   29.8  85.7    -5.5    201  1.0
  7500   19.6  67.3   140   10    5   1.4   0.8   28.7  83.7    -6.6    202  1.0
  7250   20.1  68.2   135    8    4   8.0   4.4   28.5  83.3    -6.8    180  0.9
  7000   20.6  69.1   125    6    3   6.3   3.4   28.2  82.8    -7.1    158  0.8
  6750   21.1  70.0   115    6    3   6.7   3.7   28.0  82.4    -7.3    136  0.7
  6500   21.6  70.9   105    5    3   6.7   3.7   27.8  82.0    -7.6    114  0.6
  6250   22.1  71.8   095    5    3   6.4   3.5   27.5  81.6    -7.8     92  0.5
  6000   22.5  72.5   090    5    3   7.5   4.1   27.3  81.1    -8.1     70  0.4
  5750   23.0  73.4   085    5    3   3.6   2.0   27.1  80.7    -8.4     48  0.2
  5500   23.1  73.6   090    5    3  -0.5  -0.3   26.4  79.4    -9.1     39  0.2
  5250   22.9  73.2   090    5    3  -7.8  -4.3   25.4  77.8   -10.0     38  0.2
  5000   21.6  70.9   095    5    3 -22.3 -12.3   23.5  74.4   -12.0     68  0.3

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

           08/18/2014 at 0900 MDT          |       08/18/2014 at 1200 MDT
                                           |
K index... +22.8  LI... -1.8               | K index... +21.9  LI... -2.0
CAPE... +222.1  CIN... -78.4               | CAPE... +382.9  CIN... -76.3
                                           |
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  29 15   1.9   1.0 | -63.0 -81.4  290  24 13   2.0   1.1
 45000 -59.4 -74.9  290  47 24   3.6   2.0 | -59.3 -74.7  290  40 21   3.3   1.8
 40000 -53.6 -64.5  280  49 25   6.4   3.5 | -53.9 -65.0  280  44 22   6.1   3.3
 38000 -49.8 -57.6  280  45 23   6.4   3.5 | -50.2 -58.4  280  40 21   6.2   3.4
 36000 -45.9 -50.6  280  41 21   6.4   3.5 | -46.5 -51.7  275  37 19   6.1   3.3
 34000 -41.9 -43.4  280  37 19   6.7   3.7 | -42.3 -44.1  275  34 17   7.1   3.9
 32000 -37.4 -35.3  280  33 17   6.4   3.5 | -37.5 -35.5  270  30 15   7.1   3.9
 30000 -32.5 -26.5  280  28 15   8.5   4.6 | -32.5 -26.5  265  26 13   8.6   4.7
 29000 -29.9 -21.8  280  26 13   8.5   4.6 | -29.9 -21.8  265  23 12   8.6   4.7
 28000 -27.4 -17.3  280  23 12   7.9   4.3 | -27.3 -17.1  265  22 11   7.8   4.3
 27000 -25.1 -13.2  280  22 11   7.8   4.3 | -25.0 -13.0  260  21 11   7.7   4.2
 26000 -22.7  -8.9  275  20 10   7.8   4.3 | -22.7  -8.9  260  20 10   7.7   4.2
 25000 -20.4  -4.7  275  18  9   7.3   4.0 | -20.4  -4.7  260  19 10   7.2   3.9
 24000 -18.8  -1.8  280  16  8   5.2   2.8 | -18.6  -1.5  265  17  9   5.8   3.2
 23000 -17.2   1.0  290  15  8   5.2   2.9 | -16.9   1.6  270  15  8   5.9   3.2
 22000 -15.7   3.7  295  14  7   6.4   3.5 | -15.2   4.6  275  13  7   7.0   3.8
 21000 -13.4   7.9  285  13  7   8.1   4.4 | -12.8   9.0  275  12  6   8.1   4.4
 20000 -11.0  12.2  275  12  6   8.2   4.5 | -10.5  13.1  270  11  6   8.1   4.5
 19500  -9.8  14.4  265  12  6   8.2   4.5 |  -9.3  15.3  265  10  5   8.2   4.5
 19000  -8.6  16.5  260  12  6   8.9   4.9 |  -8.0  17.6  260  10  5   8.8   4.8
 18500  -7.3  18.9  260  13  6   8.9   4.9 |  -6.7  19.9  255  10  5   8.8   4.8
 18000  -6.0  21.2  255  13  7   9.1   5.0 |  -5.4  22.3  250  10  5   8.9   4.9
 17500  -4.6  23.7  255  13  6   9.3   5.1 |  -4.1  24.6  250  10  5   8.9   4.9
 17000  -3.2  26.2  255  12  6   9.4   5.1 |  -2.8  27.0  245  11  5   9.0   4.9
 16500  -1.8  28.8  255  12  6   9.1   5.0 |  -1.5  29.3  245  10  5   9.0   4.9
 16000  -0.5  31.1  255  11  6   9.1   5.0 |  -0.2  31.6  240  10  5   9.0   4.9
 15500   0.9  33.6  255  11  6   9.1   5.0 |   1.1  34.0  240  10  5   8.9   4.9
 15000   2.9  37.2  255  10  5   9.1   5.0 |   3.1  37.6  235  10  5   8.8   4.8
 14500   4.2  39.6  255  10  5   9.3   5.1 |   4.4  39.9  235  10  5   9.0   4.9
 14000   5.6  42.1  260  10  5   9.3   5.1 |   5.7  42.3  235  10  5   8.9   4.9
 13500   7.0  44.6  260  10  5   9.3   5.1 |   7.1  44.8  235  10  5   9.2   5.1
 13000   8.3  46.9  260   9  5   9.3   5.1 |   8.4  47.1  240  10  5   9.3   5.1
 12500   9.7  49.5  260   9  5   9.1   5.0 |   9.8  49.6  240  10  5   9.0   5.0
 12000  11.0  51.8  260   9  5   8.9   4.9 |  11.1  52.0  245  10  5   8.9   4.9
 11500  12.3  54.1  260   9  4   8.7   4.8 |  12.4  54.3  245  10  5   8.7   4.8
 11000  13.5  56.3  255   9  4   8.3   4.5 |  13.6  56.5  245  10  5   8.2   4.5
 10500  14.8  58.6  255   8  4   4.5   2.5 |  14.9  58.8  250  10  5   4.6   2.5
 10250  14.9  58.8  250   8  4   4.8   2.6 |  15.1  59.2  250   9  5   5.5   3.0
 10000  15.6  60.1  245   7  4   9.8   5.4 |  15.8  60.4  245   9  4  10.8   5.9
  9750  16.2  61.2  240   7  3   9.1   5.0 |  16.5  61.7  245   8  4  10.2   5.6
  9500  16.8  62.2  235   6  3   7.0   3.8 |  17.2  63.0  245   7  4   7.2   3.9
  9250  17.2  63.0  225   6  3   5.0   2.8 |  17.6  63.7  245   6  3   5.7   3.1
  9000  17.6  63.7  215   5  3   6.6   3.6 |  18.1  64.6  240   6  3   8.4   4.6
  8750  18.1  64.6  200   5  3   6.7   3.7 |  18.7  65.7  235   5  2   8.1   4.4
  8500  18.5  65.3  190   5  3   6.0   3.3 |  19.3  66.7  225   4  2   7.8   4.3
  8250  18.9  66.0  180   6  3   5.3   2.9 |  19.9  67.8  220   4  2   7.5   4.1
  8000  19.3  66.7  175   7  3   5.2   2.8 |  20.4  68.7  210   3  2   7.5   4.1
  7750  19.7  67.5  170   8  4   4.6   2.5 |  20.9  69.6  205   3  2   7.6   4.2
  7500  20.0  68.0  165   8  4   2.8   1.5 |  21.5  70.7  200   3  2   8.6   4.7
  7250  20.1  68.2  165   9  4   1.5   0.8 |  22.1  71.8  200   3  1   9.0   4.9
  7000  20.3  68.5  160   9  5   2.3   1.2 |  22.8  73.0  200   3  1   9.1   5.0
  6750  20.4  68.7  155   9  5   1.2   0.7 |  23.4  74.1  200   3  1  10.0   5.5
  6500  20.4  68.7  155   8  4  -1.1  -0.6 |  24.2  75.6  200   3  1  10.6   5.8
  6250  20.3  68.5  145   7  4  -0.7  -0.4 |  25.0  77.0  200   3  1  11.1   6.1
  6000  20.2  68.4  135   6  3  -3.6  -2.0 |  25.8  78.4  200   3  1   9.7   5.3
  5750  20.0  68.0  115   5  2   2.2   1.2 |  26.6  79.9  205   3  1  11.6   6.4
  5500  20.6  69.1  115   4  2  11.2   6.2 |  27.6  81.7  210   3  1  15.0   8.2
  5250  21.2  70.2  110   4  2   4.1   2.3 |  28.6  83.5  210   2  1  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/18/2014 at 1500 MDT          |       08/18/2014 at 1800 MDT
                                           |
K index... +21.6  LI... -1.1               | K index... +13.2  LI... +1.0
CAPE... +253.9  CIN... -63.3               | CAPE... +0.8  CIN... -0.9
                                           |
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  280  26 13   2.0   1.1 | -63.4 -82.1  285  28 14   1.5   0.8
 45000 -59.3 -74.7  280  36 19   3.5   1.9 | -59.8 -75.6  275  45 23   4.2   2.3
 40000 -53.6 -64.5  275  43 22   5.9   3.2 | -53.2 -63.8  270  53 27   6.0   3.3
 38000 -50.0 -58.0  275  40 21   6.0   3.3 | -49.6 -57.3  265  51 26   6.1   3.3
 36000 -46.5 -51.7  270  37 19   5.9   3.2 | -46.0 -50.8  265  49 25   6.0   3.3
 34000 -42.3 -44.1  270  33 17   7.2   3.9 | -41.6 -42.9  260  43 22   7.5   4.1
 32000 -37.4 -35.3  265  30 15   7.2   3.9 | -36.5 -33.7  260  36 19   7.6   4.1
 30000 -32.2 -26.0  260  27 14   8.9   4.9 | -31.6 -24.9  260  32 17   8.3   4.5
 29000 -29.6 -21.3  260  25 13   8.9   4.9 | -29.1 -20.4  260  31 16   8.3   4.5
 28000 -27.0 -16.6  260  24 12   7.6   4.2 | -26.7 -16.1  260  29 15   7.7   4.2
 27000 -24.7 -12.5  260  23 12   7.5   4.1 | -24.4 -11.9  265  27 14   7.7   4.2
 26000 -22.5  -8.5  265  23 12   7.5   4.1 | -22.1  -7.8  270  25 13   7.7   4.2
 25000 -20.2  -4.4  265  22 11   7.3   4.0 | -19.8  -3.6  275  24 12   7.6   4.2
 24000 -18.2  -0.8  265  21 11   6.8   3.7 | -17.5   0.5  275  22 11   7.5   4.1
 23000 -16.1   3.0  265  20 10   6.8   3.8 | -15.2   4.6  280  20 10   7.5   4.1
 22000 -14.1   6.6  270  19 10   7.2   3.9 | -13.0   8.6  280  19 10   7.3   4.0
 21000 -11.9  10.6  260  17  9   7.6   4.2 | -10.9  12.4  280  17  9   7.0   3.8
 20000  -9.7  14.5  250  16  8   7.7   4.2 |  -8.8  16.2  280  15  8   7.0   3.8
 19500  -8.6  16.5  245  16  8   7.8   4.3 |  -7.8  18.0  275  14  7   6.8   3.7
 19000  -7.4  18.7  245  15  8   8.7   4.8 |  -6.6  20.1  275  14  7   8.8   4.8
 18500  -6.1  21.0  240  16  8   8.7   4.8 |  -5.4  22.3  270  14  7   8.7   4.7
 18000  -4.8  23.4  235  16  8   8.9   4.9 |  -4.1  24.6  265  13  7   8.8   4.8
 17500  -3.5  25.7  235  15  8   9.0   5.0 |  -2.8  27.0  260  13  7   9.0   5.0
 17000  -2.2  28.0  235  15  8   9.1   5.0 |  -1.5  29.3  260  14  7   9.1   5.0
 16500  -0.9  30.4  235  15  8   8.9   4.9 |  -0.2  31.6  255  14  7   9.0   4.9
 16000   0.4  32.7  235  14  7   9.0   4.9 |   1.1  34.0  255  14  7   9.1   5.0
 15500   1.7  35.1  240  14  7   8.7   4.8 |   2.4  36.3  255  14  7   8.9   4.9
 15000   3.6  38.5  240  14  7   8.6   4.7 |   4.4  39.9  255  13  7   8.8   4.8
 14500   4.9  40.8  245  13  7   9.2   5.1 |   5.7  42.3  255  13  7   9.1   5.0
 14000   6.3  43.3  245  13  7   9.2   5.0 |   7.1  44.8  255  12  6   9.1   5.0
 13500   7.6  45.7  250  13  6   9.0   4.9 |   8.4  47.1  255  12  6   9.0   4.9
 13000   9.0  48.2  255  12  6   8.9   4.9 |   9.7  49.5  260  12  6   9.0   4.9
 12500  10.3  50.5  255  11  6   9.0   4.9 |  11.1  52.0  260  11  6   8.9   4.9
 12000  11.6  52.9  260  11  6   9.1   5.0 |  12.4  54.3  265  10  5   8.8   4.8
 11500  13.0  55.4  260  11  6   8.7   4.8 |  13.7  56.7  270  10  5   8.4   4.6
 11000  14.3  57.7  265  10  5   8.1   4.5 |  14.8  58.6  270  10  5   7.6   4.1
 10500  15.5  59.9  270  10  5   5.6   3.1 |  15.9  60.6  275   9  5  10.5   5.8
 10250  15.8  60.4  270   9  5   6.5   3.6 |  16.9  62.4  275   9  5  11.4   6.2
 10000  16.6  61.9  275   9  5  10.5   5.7 |  17.5  63.5  280   9  5   7.8   4.3
  9750  17.3  63.1  275   9  4   9.8   5.4 |  18.1  64.6  280   9  4   9.2   5.0
  9500  18.0  64.4  275   8  4   8.6   4.7 |  18.7  65.7  280   8  4   7.5   4.1
  9250  18.6  65.5  280   8  4   7.7   4.2 |  19.2  66.6  285   8  4   7.2   3.9
  9000  19.2  66.6  280   7  4   8.6   4.7 |  19.8  67.6  285   7  4   8.4   4.6
  8750  19.8  67.6  285   7  4   8.5   4.7 |  20.4  68.7  290   7  3   8.0   4.4
  8500  20.4  68.7  290   6  3   8.1   4.5 |  21.0  69.8  295   6  3   8.2   4.5
  8250  20.9  69.6  290   6  3   7.9   4.3 |  21.6  70.9  295   5  3   8.2   4.5
  8000  21.5  70.7  290   6  3   9.0   5.0 |  22.2  72.0  300   4  2   7.8   4.3
  7750  22.2  72.0  290   6  3   9.6   5.3 |  22.7  72.9  305   4  2   7.1   3.9
  7500  22.9  73.2  290   6  3   9.9   5.4 |  23.3  73.9  305   3  2   8.8   4.8
  7250  23.6  74.5  290   6  3  10.4   5.7 |  24.0  75.2  305   3  2  10.7   5.9
  7000  24.4  75.9  290   6  3  10.0   5.5 |  24.8  76.6  305   3  2   9.9   5.4
  6750  25.1  77.2  290   6  3  10.1   5.6 |  25.5  77.9  300   3  2   9.5   5.2
  6500  25.9  78.6  290   6  3  10.9   6.0 |  26.2  79.2  300   3  1  10.1   5.5
  6250  26.7  80.1  290   6  3  11.7   6.4 |  27.0  80.6  300   3  1  10.7   5.9
  6000  27.6  81.7  285   6  3   9.3   5.1 |  27.8  82.0  295   3  1  10.0   5.5
  5750  28.3  82.9  285   5  3  11.3   6.2 |  28.5  83.3  295   3  1   9.2   5.0
  5500  29.3  84.7  285   6  3  16.3   9.0 |  29.1  84.4  295   3  1   9.3   5.1
  5250  30.4  86.7  290   6  3  13.2   7.2 |  29.8  85.6  300   3  1   9.8   5.4
  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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