Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 181239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Friday, July 18, 2014

This forecast is for Friday, July 18, 2014:

If the trigger temperature of 87.0 F/30.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1057 ft/min (5.4 m/s)
   Maximum height of thermals.................. 18060 ft MSL (13221 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11784 ft MSL (6944 ft AGL)
Thermal soaring outlook for Saturday 07/19..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:02:55 / 20:37:59 MDT
Total possible sunshine........... 14 hr 35 min 4 sec (875 min 4 sec)
Altitude of sun at 13:20:21 MDT... 71.79 degrees

Upper air data from rawinsonde observation taken on 07/18/2014 at 0600 MDT

Freezing level.................. 15537 ft MSL (10698 ft AGL)
Convective condensation level... 16873 ft MSL (12034 ft AGL)
Lifted condensation level....... 17901 ft MSL (13061 ft AGL)
Lifted index.................... -0.3
K index......................... +21.8

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  -64.7 -84.5   255   18    9   4.1   2.3   87.3 189.1    30.6      M    M
 45000  -62.0 -79.6   285   38   20   5.4   3.0   65.9 150.7    19.6      M    M
 40000  -53.6 -64.5   285   42   21   4.2   2.3   56.5 133.6    14.7      M    M
 38000  -50.0 -58.0   295   45   23   7.7   4.2   53.1 127.5    12.7      M    M
 36000  -45.8 -50.4   305   51   26   7.3   4.0   50.8 123.4    11.5      M    M
 34000  -40.8 -41.4   295   46   24   8.8   4.8   49.5 121.0    10.8      M    M
 32000  -34.8 -30.6   290   41   21   8.7   4.8   48.6 119.6    10.5      M    M
 30000  -30.4 -22.7   285   38   19   6.8   3.7   46.8 116.3     9.4      M    M
 29000  -28.3 -18.9   285   35   18   7.8   4.3   45.8 114.4     8.7      M    M
 28000  -25.9 -14.6   280   33   17   7.8   4.3   45.0 113.1     8.2      M    M
 27000  -23.7 -10.7   280   31   16   7.1   3.9   44.2 111.6     7.6      M    M
 26000  -21.6  -6.9   280   28   15   7.3   4.0   43.3 109.9     6.9      M    M
 25000  -19.3  -2.7   275   26   13   8.6   4.7   42.6 108.7     6.4      M    M
 24000  -16.5   2.3   270   24   12   8.2   4.5   42.4 108.3     6.3      M    M
 23000  -14.6   5.7   280   23   12   6.2   3.4   41.1 106.0     5.3      M    M
 22000  -12.8   9.0   290   22   11   6.3   3.5   39.9 103.8     4.3      M    M
 21000  -10.6  12.9   300   22   11   7.4   4.1   38.9 101.9     3.7      M    M
 20000   -8.6  16.5   300   23   12   3.9   2.1   37.8 100.0     2.8      M    M
 19500   -7.9  17.8   300   22   11   6.2   3.4   36.8  98.3     2.0      M    M
 19000   -6.8  19.8   300   21   11   5.2   2.9   36.3  97.4     1.6      M    M
 18500   -6.1  21.0   300   20   10   5.0   2.8   35.5  95.9     0.9      M    M
 18000   -5.4  22.3   305   19   10   5.3   2.9   34.7  94.4     0.1      M    M
 17500   -5.4  22.3   305   16    8  10.1   5.5   32.6  90.7    -2.1   1239  6.3
 17000   -4.0  24.8   300   13    7   9.7   5.3   32.6  90.6    -2.2   1181  6.0
 16500   -2.5  27.5   300   11    6   9.7   5.3   32.6  90.6    -2.2   1123  5.7
 16000   -1.1  30.0   295    9    5   9.7   5.3   32.6  90.7    -2.2   1065  5.4
 15500    0.3  32.5   295    9    5   9.3   5.1   32.5  90.6    -2.3   1008  5.1
 15000    1.7  35.1   295    9    5   9.3   5.1   32.5  90.4    -2.4    954  4.8
 14500    3.0  37.4   295    9    5   9.3   5.1   32.4  90.3    -2.6    900  4.6
 14000    4.4  39.9   295    9    5   9.3   5.1   32.4  90.2    -2.6    843  4.3
 13500    5.7  42.3   290    9    5   9.3   5.1   32.3  90.1    -2.7    787  4.0
 13000    7.1  44.8   280    9    5   9.3   5.1   32.2  90.0    -2.8    731  3.7
 12500    8.5  47.3   275   10    5   9.3   5.1   32.2  89.9    -2.9    674  3.4
 12000    9.9  49.8   270   10    5   9.3   5.1   32.1  89.8    -2.9    618  3.1
 11500   11.3  52.3   265   10    5   9.3   5.1   32.0  89.6    -3.1    562  2.9
 11000   12.7  54.9   265    9    5   9.3   5.1   31.9  89.5    -3.2    506  2.6
 10500   14.0  57.2   260    9    5   9.2   5.1   31.9  89.4    -3.3    449  2.3
 10250   14.7  58.5   260    9    5   8.9   4.9   31.8  89.3    -3.3    422  2.1
 10000   15.4  59.7   255    9    4   8.8   4.8   31.7  89.1    -3.4    394  2.0
  9750   16.0  60.8   250    8    4   8.8   4.9   31.7  89.0    -3.5    367  1.9
  9500   16.7  62.1   250    8    4   8.8   4.8   31.6  88.9    -3.6    340  1.7
  9250   17.4  63.3   245    8    4   8.8   4.8   31.5  88.8    -3.6    313  1.6
  9000   18.0  64.4   240    8    4   8.9   4.9   31.5  88.7    -3.7    285  1.4
  8750   18.7  65.7   230    8    4   8.7   4.8   31.4  88.5    -3.8    258  1.3
  8500   19.4  66.9   215    8    4   9.2   5.0   31.3  88.4    -3.8    231  1.2
  8250   20.0  68.0   200    8    4   7.6   4.2   31.3  88.3    -3.9    204  1.0
  8000   20.4  68.7   190    9    5   5.4   3.0   31.0  87.8    -4.2    184  0.9
  7750   20.8  69.4   175   10    5   4.6   2.5   30.6  87.1    -4.6    166  0.8
  7500   21.1  70.0   165   11    6   7.0   3.8   30.3  86.5    -5.1    149  0.8
  7250   21.3  70.3   155   13    6  -9.2  -5.0   29.7  85.5    -5.6    137  0.7
  7000   20.2  68.4   145   15    7  -4.2  -2.3   27.9  82.2    -7.4    160  0.8
  6750   20.8  69.4   140   13    7   7.3   4.0   27.8  82.0    -7.6    136  0.7
  6500   20.8  69.4   130   11    6  -2.6  -1.4   27.0  80.6    -8.4    129  0.7
  6250   20.8  69.4   115   10    5   4.0   2.2   26.3  79.3    -9.1    120  0.6
  6000   21.3  70.3   100    9    5   7.0   3.9   26.0  78.9    -9.3     99  0.5
  5750   21.7  71.1   095    9    4   5.6   3.1   25.8  78.4    -9.6     78  0.4
  5500   22.2  72.0   095    8    4   8.3   4.6   25.5  77.9    -9.9     57  0.3
  5250   22.7  72.9   100    8    4  -1.2  -0.7   25.3  77.5   -10.2     36  0.2
  5000   21.7  71.1   100    7    4 -24.8 -13.6   23.5  74.3   -12.0     59  0.3

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

           07/18/2014 at 0900 MDT          |       07/18/2014 at 1200 MDT
                                           |
K index... +20.2  LI... +1.1               | K index... +21.6  LI... -0.2
CAPE... 0.0  CIN... -0.6                   | CAPE... +7.3  CIN... -73.5
                                           |
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 -64.7 -84.5  275  24 12   1.5   0.8 | -64.5 -84.1  275  30 15   0.8   0.4
 45000 -61.0 -77.8  280  36 19   4.6   2.5 | -61.5 -78.7  275  40 21   4.6   2.5
 40000 -53.5 -64.3  285  40 20   7.8   4.3 | -54.0 -65.2  275  37 19   7.9   4.3
 38000 -48.7 -55.7  285  39 20   7.8   4.3 | -49.2 -56.6  275  37 19   8.0   4.4
 36000 -44.0 -47.2  290  38 20   7.9   4.3 | -44.4 -47.9  275  36 19   8.0   4.4
 34000 -39.5 -39.1  290  38 20   7.5   4.1 | -39.7 -39.5  280  36 18   7.9   4.3
 32000 -34.4 -29.9  295  38 20   8.0   4.4 | -34.3 -29.7  290  35 18   8.3   4.5
 30000 -30.1 -22.2  295  36 18   7.2   4.0 | -29.9 -21.8  290  32 16   7.3   4.0
 29000 -27.9 -18.2  295  34 18   7.3   4.0 | -27.7 -17.9  295  30 16   7.3   4.0
 28000 -25.8 -14.4  295  33 17   6.7   3.7 | -25.6 -14.1  295  29 15   6.9   3.8
 27000 -23.8 -10.8  290  32 16   6.6   3.6 | -23.5 -10.3  295  30 15   6.9   3.8
 26000 -21.8  -7.2  290  31 16   6.6   3.6 | -21.5  -6.7  295  31 16   7.0   3.8
 25000 -19.8  -3.6  285  31 16   6.6   3.6 | -19.4  -2.9  295  32 16   6.8   3.7
 24000 -17.8  -0.0  285  29 15   6.9   3.8 | -17.5   0.5  295  32 16   6.4   3.5
 23000 -15.8   3.6  285  28 14   6.9   3.8 | -15.7   3.7  295  32 16   6.4   3.5
 22000 -13.8   7.2  285  26 14   7.1   3.9 | -13.8   7.2  295  31 16   6.7   3.7
 21000 -11.7  10.9  295  25 13   7.2   4.0 | -11.7  10.9  295  29 15   7.2   3.9
 20000  -9.6  14.7  300  23 12   7.2   4.0 |  -9.6  14.7  300  27 14   7.2   3.9
 19500  -8.5  16.7  305  23 12   7.3   4.0 |  -8.5  16.7  300  26 14   7.2   4.0
 19000  -7.5  18.5  305  22 12   6.5   3.6 |  -7.4  18.7  305  26 13   7.3   4.0
 18500  -6.5  20.3  310  22 11   6.7   3.7 |  -6.4  20.5  305  27 14   7.3   4.0
 18000  -5.6  21.9  310  22 11   7.2   3.9 |  -5.3  22.5  305  27 14   7.5   4.1
 17500  -4.4  24.1  310  21 11   7.8   4.3 |  -4.2  24.4  305  27 14   7.7   4.2
 17000  -3.3  26.1  305  21 11   7.8   4.3 |  -3.1  26.4  305  27 14   7.7   4.2
 16500  -2.1  28.2  305  20 10   8.1   4.4 |  -1.9  28.6  305  25 13   7.7   4.2
 16000  -0.9  30.4  300  19 10   8.1   4.4 |  -0.8  30.6  305  24 12   7.7   4.2
 15500   1.0  33.8  300  17  9   8.4   4.6 |   0.4  32.7  300  22 11   8.5   4.7
 15000   2.2  36.0  300  16  8   8.3   4.6 |   2.4  36.3  300  19 10   8.7   4.8
 14500   3.5  38.3  300  15  8   8.7   4.8 |   3.7  38.7  300  18  9   9.0   4.9
 14000   4.7  40.5  300  14  7   8.7   4.8 |   5.0  41.0  300  16  8   9.0   4.9
 13500   6.0  42.8  300  13  7   8.9   4.9 |   6.3  43.3  300  14  7   8.4   4.6
 13000   7.4  45.3  300  13  6   9.0   4.9 |   7.5  45.5  305  13  6   8.2   4.5
 12500   8.7  47.7  300  12  6   9.0   5.0 |   8.8  47.8  305  11  6   8.5   4.7
 12000  10.0  50.0  300  11  6   9.0   5.0 |  10.1  50.2  310   9  5   8.7   4.8
 11500  11.4  52.5  300  10  5   8.7   4.8 |  11.3  52.3  310   8  4   8.7   4.8
 11000  12.6  54.7  300  10  5   8.0   4.4 |  12.6  54.7  315   7  4   8.5   4.7
 10500  13.8  56.8  295   9  5   4.9   2.7 |  13.9  57.0  320   6  3   5.6   3.1
 10250  14.0  57.2  295   9  4   5.2   2.8 |  14.2  57.6  320   6  3   6.6   3.6
 10000  14.7  58.5  290   8  4   9.6   5.2 |  15.0  59.0  320   6  3  11.2   6.1
  9750  15.3  59.5  285   8  4   8.6   4.7 |  15.7  60.3  325   5  3  10.5   5.8
  9500  16.0  60.8  285   8  4   8.1   4.4 |  16.5  61.7  325   5  3   8.4   4.6
  9250  16.5  61.7  280   7  4   7.3   4.0 |  17.0  62.6  325   4  2   6.8   3.8
  9000  17.1  62.8  280   7  3   7.8   4.3 |  17.6  63.7  325   4  2   8.4   4.6
  8750  17.6  63.7  280   6  3   8.1   4.4 |  18.2  64.8  320   4  2   8.2   4.5
  8500  18.2  64.8  280   5  3   6.9   3.8 |  18.8  65.8  320   3  2   8.2   4.5
  8250  18.6  65.5  275   4  2   5.9   3.2 |  19.3  66.7  320   3  2   8.1   4.5
  8000  19.0  66.2  265   3  2   4.6   2.5 |  19.9  67.8  320   3  1   8.0   4.4
  7750  19.3  66.7  245   3  1   3.3   1.8 |  20.5  68.9  320   3  1   8.3   4.5
  7500  19.6  67.3  215   2  1   5.6   3.1 |  21.1  70.0  315   3  1   9.7   5.3
  7250  20.1  68.2  195   3  1   6.6   3.6 |  21.9  71.4  315   3  1  10.6   5.8
  7000  20.6  69.1  180   4  2   6.7   3.7 |  22.6  72.7  310   3  1   9.8   5.4
  6750  21.0  69.8  170   4  2   5.9   3.3 |  23.4  74.1  310   2  1  10.1   5.5
  6500  21.3  70.3  165   4  2   3.8   2.1 |  24.2  75.6  305   2  1  11.0   6.0
  6250  21.5  70.7  155   4  2   3.8   2.1 |  25.0  77.0  305   2  1  11.5   6.3
  6000  21.8  71.2  145   4  2   2.7   1.5 |  25.9  78.6  300   2  1   9.8   5.4
  5750  22.0  71.6  135   3  2   7.0   3.8 |  26.6  79.9  300   2  1  12.6   6.9
  5500  22.8  73.0  135   3  2  12.4   6.8 |  27.8  82.0  300   2  1  17.2   9.4
  5250  23.6  74.5  130   3  2   8.2   4.5 |  28.9  84.0  305   2  1  13.6   7.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/18/2014 at 1500 MDT          |       07/18/2014 at 1800 MDT
                                           |
K index... +23.6  LI... -0.1               | K index... +21.7  LI... -0.6
CAPE... +7.3  CIN... -24.0                 | CAPE... 0.0  CIN... -52.5
                                           |
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 -64.6 -84.3  275  30 15   0.6   0.3 | -64.5 -84.1  275  30 16   1.1   0.6
 45000 -61.6 -78.9  280  42 22   5.1   2.8 | -61.2 -78.2  280  40 21   4.9   2.7
 40000 -53.5 -64.3  270  43 22   7.3   4.0 | -52.9 -63.2  275  47 24   7.1   3.9
 38000 -49.1 -56.4  275  40 21   7.4   4.0 | -48.7 -55.7  280  41 21   7.1   3.9
 36000 -44.7 -48.5  275  38 20   7.3   4.0 | -44.5 -48.1  280  36 18   7.3   4.0
 34000 -39.9 -39.8  280  37 19   8.0   4.4 | -39.6 -39.3  280  34 17   8.1   4.4
 32000 -34.5 -30.1  275  35 18   8.5   4.7 | -34.8 -30.6  275  32 17   8.0   4.4
 30000 -29.9 -21.8  280  32 16   7.7   4.2 | -30.2 -22.4  275  29 15   7.8   4.3
 29000 -27.6 -17.7  285  30 16   7.7   4.2 | -27.9 -18.2  280  27 14   7.8   4.3
 28000 -25.4 -13.7  285  29 15   6.9   3.8 | -25.6 -14.1  280  25 13   7.4   4.1
 27000 -23.3  -9.9  290  28 15   6.9   3.8 | -23.5 -10.3  285  24 13   7.3   4.0
 26000 -21.3  -6.3  290  28 14   6.9   3.8 | -20.8  -5.4  285  23 12   7.3   4.0
 25000 -19.3  -2.7  290  27 14   6.8   3.8 | -18.7  -1.7  290  22 12   6.7   3.7
 24000 -17.3   0.9  295  26 13   6.7   3.7 | -16.8   1.8  295  21 11   6.4   3.5
 23000 -15.3   4.5  295  25 13   6.7   3.7 | -14.9   5.2  295  21 11   6.4   3.5
 22000 -13.4   7.9  295  24 12   6.9   3.8 | -13.1   8.4  300  20 10   6.4   3.5
 21000 -11.2  11.8  300  24 12   7.2   3.9 | -11.2  11.8  300  19 10   6.4   3.5
 20000  -9.1  15.6  305  23 12   7.2   3.9 |  -9.3  15.3  305  18  9   6.4   3.5
 19500  -8.0  17.6  305  23 12   7.2   3.9 |  -8.4  16.9  305  17  9   6.6   3.6
 19000  -6.9  19.6  310  22 11   7.7   4.2 |  -7.3  18.9  305  16  8   7.8   4.3
 18500  -5.8  21.6  310  22 11   7.7   4.2 |  -6.1  21.0  305  15  8   7.7   4.2
 18000  -4.7  23.5  315  21 11   7.6   4.2 |  -4.9  23.2  305  15  8   8.9   4.9
 17500  -3.6  25.5  315  21 11   7.6   4.2 |  -3.6  25.5  305  15  8   9.3   5.1
 17000  -2.4  27.7  315  21 11   7.6   4.2 |  -2.2  28.0  310  15  8   9.3   5.1
 16500  -1.3  29.7  315  20 10   7.5   4.1 |  -0.8  30.6  305  15  8   9.2   5.0
 16000  -0.2  31.6  310  19 10   7.5   4.1 |   0.6  33.1  305  15  8   9.2   5.1
 15500   1.5  34.7  310  17  9   8.1   4.5 |   1.9  35.4  305  15  8   8.7   4.8
 15000   2.7  36.9  305  15  8   8.1   4.4 |   3.1  37.6  300  14  7   8.7   4.8
 14500   3.9  39.0  305  14  7   8.7   4.8 |   4.4  39.9  300  14  7   8.7   4.8
 14000   5.2  41.4  305  13  7   8.7   4.8 |   5.7  42.3  300  13  7   8.8   4.8
 13500   6.5  43.7  305  13  7   9.0   4.9 |   7.0  44.6  300  13  7   8.8   4.8
 13000   7.8  46.0  305  12  6   9.0   4.9 |   8.9  48.0  305  12  6   8.7   4.8
 12500   9.1  48.4  305  12  6   8.8   4.8 |  10.2  50.4  305  12  6   8.6   4.7
 12000  10.4  50.7  310  11  5   8.7   4.8 |  11.5  52.7  310  11  6   8.5   4.7
 11500  11.7  53.1  310  10  5   8.9   4.9 |  12.7  54.9  310  11  6   8.8   4.8
 11000  13.1  55.6  315   9  5   8.9   4.9 |  14.1  57.4  310  10  5   8.7   4.8
 10500  14.4  57.9  315   8  4   5.2   2.8 |  15.4  59.7  315   9  5   5.4   3.0
 10250  14.7  58.5  315   8  4   6.4   3.5 |  15.7  60.3  315   9  5   6.1   3.3
 10000  15.5  59.9  315   8  4  12.1   6.6 |  16.4  61.5  310   8  4  10.9   6.0
  9750  16.3  61.3  315   7  4  11.4   6.3 |  17.1  62.8  310   8  4  10.2   5.6
  9500  17.1  62.8  320   7  4   8.5   4.6 |  17.9  64.2  310   7  4   8.3   4.6
  9250  17.6  63.7  315   7  3   7.5   4.1 |  18.4  65.1  310   7  4   7.6   4.1
  9000  18.4  65.1  315   6  3  10.5   5.8 |  19.0  66.2  310   7  3   9.3   5.1
  8750  19.1  66.4  315   6  3  10.0   5.5 |  19.7  67.5  310   6  3   8.9   4.9
  8500  19.8  67.6  315   6  3   9.9   5.4 |  20.4  68.7  305   6  3   8.6   4.7
  8250  20.6  69.1  315   6  3   9.8   5.4 |  21.0  69.8  305   6  3   8.3   4.6
  8000  21.3  70.3  315   6  3  10.2   5.6 |  21.6  70.9  300   5  3   9.2   5.0
  7750  22.1  71.8  315   6  3  10.4   5.7 |  22.3  72.1  300   5  3   9.6   5.2
  7500  22.9  73.2  315   6  3  10.2   5.6 |  23.0  73.4  300   5  3   9.9   5.4
  7250  23.6  74.5  315   6  3  10.1   5.5 |  23.8  74.8  300   5  3  10.3   5.7
  7000  24.4  75.9  315   5  3  10.1   5.5 |  24.5  76.1  295   5  3   9.6   5.3
  6750  25.1  77.2  310   5  3  10.5   5.8 |  25.2  77.4  295   5  2   9.7   5.3
  6500  25.9  78.6  310   5  3  11.0   6.0 |  26.0  78.8  295   5  2  10.7   5.8
  6250  26.8  80.2  310   5  3  11.5   6.3 |  26.8  80.2  290   5  2  11.4   6.3
  6000  27.6  81.7  310   5  2  10.0   5.5 |  27.6  81.7  290   5  2   9.4   5.1
  5750  28.3  82.9  310   5  2  12.9   7.1 |  28.2  82.8  290   4  2   9.8   5.4
  5500  29.5  85.1  310   5  2  17.3   9.5 |  29.1  84.4  290   4  2  12.8   7.0
  5250  30.7  87.3  310   5  2  13.8   7.6 |  30.0  86.0  290   5  2  10.6   5.8
  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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