Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 161257
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0657 MDT Saturday, August 16, 2014

This forecast is for Saturday, August 16, 2014:

If the trigger temperature of 85.0 F/29.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1415 ft/min (7.2 m/s)
   Maximum height of thermals.................. 17834 ft MSL (12995 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1130 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................. 11868 ft MSL (7029 ft AGL)
Thermal soaring outlook for Sunday 08/17....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:28:17 / 20:08:57 MDT
Total possible sunshine........... 13 hr 40 min 40 sec (820 min 40 sec)
Altitude of sun at 13:18:16 MDT... 64.44 degrees

Upper air data from rawinsonde observation taken on 08/16/2014 at 0600 MDT

Freezing level.................. 15266 ft MSL (10427 ft AGL)
Convective condensation level... 14080 ft MSL (9241 ft AGL)
Lifted condensation level....... 15273 ft MSL (10434 ft AGL)
Lifted index.................... -4.0
K index......................... +30.0

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  -64.9 -84.8   255   17    9   3.5   1.9   86.3 187.3    30.4      M    M
 45000  -62.8 -81.0   275   33   17  -1.4  -0.8   65.4 149.8    19.6      M    M
 40000  -53.4 -64.1   275   29   15   6.5   3.6   57.1 134.7    15.4      M    M
 38000  -49.0 -56.2   265   31   16   6.4   3.5   53.9 129.0    13.7      M    M
 36000  -44.8 -48.6   265   27   14   8.2   4.5   51.5 124.7    12.4      M    M
 34000  -40.0 -40.0   280   24   12   8.0   4.4   50.0 122.0    11.6      M    M
 32000  -35.2 -31.4   285   20   11   8.0   4.4   48.6 119.5    10.9      M    M
 30000  -30.0 -22.0   295   19   10   6.8   3.7   47.7 117.9    10.5      M    M
 29000  -28.1 -18.6   295   20   10   6.4   3.5   46.2 115.2     9.5      M    M
 28000  -26.2 -15.2   300   21   11   6.4   3.5   44.9 112.7     8.5      M    M
 27000  -24.3 -11.7   300   21   11   6.3   3.4   43.7 110.6     7.7      M    M
 26000  -22.1  -7.8   305   22   11   7.9   4.3   42.8 109.0     7.1      M    M
 25000  -19.7  -3.5   305   23   12   8.0   4.4   42.1 107.8     6.6      M    M
 24000  -17.3   0.9   305   19   10   8.2   4.5   41.5 106.7     6.2      M    M
 23000  -14.8   5.4   310   15    8   8.2   4.5   41.0 105.8     5.8      M    M
 22000  -12.4   9.7   305   16    8   8.2   4.5   40.3 104.6     5.3      M    M
 21000   -9.9  14.2   300   17    9   8.2   4.5   39.8 103.6     4.9      M    M
 20000   -8.2  17.2   275   15    8   2.3   1.3   37.6  99.7     3.1      M    M
 19500   -7.7  18.1   270   13    7   1.9   1.1   36.5  97.6     2.1      M    M
 19000   -7.5  18.5   270   13    7   5.3   2.9   35.2  95.3     0.9      M    M
 18500   -6.5  20.3   280   12    6   7.6   4.2   34.6  94.2     0.4      M    M
 18000   -5.4  22.3   290   11    6   7.4   4.1   34.2  93.5     0.1      M    M
 17500   -4.4  24.1   305   13    7   6.2   3.4   33.6  92.5    -0.4   1178  6.0
 17000   -3.5  25.7   315   15    8   6.5   3.6   33.1  91.5    -1.0   1137  5.8
 16500   -3.0  26.6   310   16    8   5.4   3.0   32.3  90.1    -2.0   1105  5.6
 16000   -1.9  28.6   305   17    9   9.2   5.0   32.0  89.5    -2.4   1060  5.4
 15500   -0.5  31.1   300   16    8   9.6   5.3   31.9  89.4    -2.5   1003  5.1
 15000    0.9  33.6   300   16    8   9.6   5.3   31.9  89.4    -2.6    945  4.8
 14500    2.4  36.3   300   15    8   9.6   5.3   31.9  89.3    -2.6    887  4.5
 14000    3.8  38.8   295   15    8   9.6   5.3   31.9  89.4    -2.6    829  4.2
 13500    5.2  41.4   300   14    7   9.5   5.2   31.8  89.3    -2.7    772  3.9
 13000    6.6  43.9   300   12    6   9.5   5.2   31.8  89.2    -2.8    716  3.6
 12500    8.0  46.4   305   11    6   9.6   5.3   31.7  89.1    -2.9    660  3.4
 12000    9.3  48.7   310   10    5   9.9   5.4   31.7  89.1    -2.9    604  3.1
 11500   10.6  51.1   300    9    5   9.0   4.9   31.7  89.1    -3.2    551  2.8
 11000   11.8  53.2   290    9    5   9.0   4.9   31.6  88.8    -3.4    500  2.5
 10500   13.0  55.4   280    9    5   8.1   4.4   31.3  88.4    -3.8    450  2.3
 10250   13.6  56.5   280    8    4   9.1   5.0   31.3  88.3    -3.9    424  2.2
 10000   14.3  57.7   275    7    4   9.1   5.0   31.2  88.2    -3.9    396  2.0
  9750   14.9  58.8   275    6    3   9.1   5.0   31.1  88.1    -4.0    369  1.9
  9500   15.6  60.1   270    5    3   9.1   5.0   31.1  88.0    -4.1    341  1.7
  9250   16.3  61.3   265    4    2   9.0   5.0   31.1  87.9    -4.1    314  1.6
  9000   16.9  62.4   255    3    2   9.4   5.1   31.0  87.8    -4.2    287  1.5
  8750   17.6  63.7   255    3    2   8.2   4.5   31.0  87.8    -4.3    259  1.3
  8500   18.0  64.4   250    3    2   1.0   0.6   30.6  87.1    -4.6    240  1.2
  8250   18.0  64.4   250    4    2   2.9   1.6   29.8  85.7    -5.4    233  1.2
  8000   18.6  65.5   250    4    2   9.1   5.0   29.7  85.4    -5.5    208  1.1
  7750   19.2  66.6   215    3    2   7.8   4.3   29.6  85.2    -5.7    182  0.9
  7500   19.8  67.6   180    5    2   9.3   5.1   29.4  85.0    -5.8    156  0.8
  7250   20.4  68.7   160    7    4   3.2   1.8   29.3  84.7    -5.9    131  0.7
  7000   20.3  68.5   150    9    5  -2.5  -1.4   28.5  83.2    -6.8    127  0.6
  6750   20.2  68.4   140    9    5  -0.7  -0.4   27.6  81.7    -7.6    122  0.6
  6500   20.1  68.2   130    8    4  -2.0  -1.1   26.8  80.2    -8.5    117  0.6
  6250   20.0  68.0   115    8    4   1.5   0.8   25.9  78.7    -9.3    113  0.6
  6000   20.4  68.7   100    8    4   7.1   3.9   25.6  78.0    -9.7     95  0.5
  5750   20.9  69.6   095    8    4   6.5   3.6   25.4  77.7   -10.0     73  0.4
  5500   21.4  70.5   095    8    4   9.8   5.4   25.2  77.3   -10.2     50  0.3
  5250   21.7  71.1   095    8    4  -6.7  -3.7   24.9  76.8   -10.6     32  0.2
  5000   19.8  67.6   095    8    4 -39.0 -21.4   22.3  72.2   -13.3     82  0.4

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

           08/16/2014 at 0900 MDT          |       08/16/2014 at 1200 MDT
                                           |
K index... +28.5  LI... -2.2               | K index... +22.7  LI... -1.5
CAPE... +426.4  CIN... -24.5               | CAPE... +517.5  CIN... -33.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.5 -84.1  295  23 12   0.3   0.2 | -65.3 -85.5  305  28 15   0.1   0.1
 45000 -61.7 -79.1  295  33 17   5.4   3.0 | -62.3 -80.1  300  43 22   6.2   3.4
 40000 -53.3 -63.9  290  31 16   7.2   3.9 | -52.8 -63.0  300  37 19   6.8   3.7
 38000 -48.9 -56.0  290  28 15   7.2   4.0 | -48.8 -55.8  295  32 16   6.8   3.7
 36000 -44.1 -47.4  290  25 13   7.2   4.0 | -44.2 -47.6  290  26 13   6.9   3.8
 34000 -39.8 -39.6  290  23 12   7.2   3.9 | -39.9 -39.8  295  22 11   7.1   3.9
 32000 -35.4 -31.7  295  20 10   7.3   4.0 | -35.7 -32.3  295  18  9   7.3   4.0
 30000 -30.8 -23.4  305  20 10   7.8   4.3 | -31.0 -23.8  300  16  8   7.9   4.3
 29000 -28.5 -19.3  305  20 10   7.8   4.3 | -28.6 -19.5  300  16  8   7.9   4.3
 28000 -26.2 -15.2  310  19 10   7.5   4.1 | -26.3 -15.3  300  15  8   7.5   4.1
 27000 -23.9 -11.0  310  18 10   7.5   4.1 | -24.0 -11.2  305  15  8   7.5   4.1
 26000 -21.7  -7.1  310  18  9   7.5   4.1 | -21.8  -7.2  305  15  8   7.5   4.1
 25000 -19.4  -2.9  310  17  9   7.6   4.2 | -19.5  -3.1  305  15  8   7.5   4.1
 24000 -17.1   1.2  305  16  8   7.9   4.3 | -17.3   0.9  305  15  8   7.6   4.2
 23000 -14.7   5.5  305  15  8   7.9   4.3 | -15.0   5.0  305  15  8   7.6   4.2
 22000 -12.4   9.7  305  14  7   7.1   3.9 | -12.7   9.1  310  15  8   7.4   4.1
 21000 -10.3  13.5  300  13  7   5.8   3.2 | -10.0  14.0  305  15  8   7.2   3.9
 20000  -8.6  16.5  295  12  6   5.8   3.2 |  -7.9  17.8  300  15  8   7.1   3.9
 19500  -7.8  18.0  295  12  6   5.9   3.2 |  -6.8  19.8  300  15  8   5.8   3.2
 19000  -6.9  19.6  295  12  6   5.9   3.2 |  -6.1  21.0  295  14  7   4.8   2.7
 18500  -6.1  21.0  295  11  6   5.8   3.2 |  -5.4  22.3  295  13  7   4.6   2.5
 18000  -5.2  22.6  295  11  6   7.3   4.0 |  -4.6  23.7  295  12  6   7.2   3.9
 17500  -4.2  24.4  295  11  6   7.2   4.0 |  -3.6  25.5  300  12  6   7.0   3.8
 17000  -3.1  26.4  295  11  6   7.3   4.0 |  -2.6  27.3  300  12  6   7.1   3.9
 16500  -2.1  28.2  300  11  5   7.3   4.0 |  -1.6  29.1  305  12  6   7.2   3.9
 16000  -1.1  30.0  305  10  5   7.4   4.1 |  -0.6  30.9  305  12  6   7.4   4.1
 15500   0.1  32.2  305  10  5   8.8   4.8 |   0.6  33.1  310  11  6   8.4   4.6
 15000   1.4  34.5  310  10  5   8.7   4.8 |   1.7  35.1  310  10  5   8.5   4.7
 14500   2.6  36.7  310   9  5   8.8   4.9 |   2.9  37.2  315   9  5   8.8   4.8
 14000   3.9  39.0  310   9  5   8.9   4.9 |   4.1  39.4  315   8  4   8.8   4.8
 13500   5.2  41.4  310   8  4   9.0   4.9 |   5.4  41.7  320   8  4   9.2   5.0
 13000   6.5  43.7  310   8  4   9.0   5.0 |   6.7  44.1  320   7  4   9.2   5.1
 12500   7.8  46.0  310   7  4   8.8   4.8 |   8.1  46.6  320   7  3   9.2   5.1
 12000   9.0  48.2  310   6  3   8.5   4.7 |   9.4  48.9  320   6  3   9.2   5.1
 11500  10.3  50.5  315   6  3   8.5   4.7 |  10.7  51.3  315   5  3   9.1   5.0
 11000  11.5  52.7  315   6  3   8.3   4.5 |  12.0  53.6  310   4  2   8.6   4.7
 10500  12.7  54.9  315   6  3   4.0   2.2 |  13.3  55.9  305   4  2   4.1   2.2
 10250  12.9  55.2  315   6  3   5.7   3.1 |  13.5  56.3  310   3  2   5.3   2.9
 10000  13.7  56.7  315   5  3  12.7   7.0 |  14.2  57.6  310   3  2  12.3   6.7
  9750  14.5  58.1  315   5  3  11.8   6.5 |  15.0  59.0  310   3  1  10.9   6.0
  9500  15.3  59.5  320   5  3   9.2   5.0 |  15.8  60.4  310   2  1   9.0   4.9
  9250  15.8  60.4  320   5  2   5.7   3.1 |  16.3  61.3  305   2  1   6.9   3.8
  9000  16.3  61.3  325   4  2   7.7   4.2 |  16.9  62.4  305   2  1   8.7   4.8
  8750  17.0  62.6  330   4  2   9.1   5.0 |  17.5  63.5  300   2  1   9.2   5.1
  8500  17.6  63.7  335   3  1   6.5   3.6 |  18.1  64.6  300   1  1   7.8   4.3
  8250  18.0  64.4  350   2  1   4.4   2.4 |  18.6  65.5  285   1  1   6.6   3.6
  8000  18.5  65.3  030   1  1   5.0   2.7 |  19.1  66.4  270   1  0   7.4   4.1
  7750  18.8  65.8  090   2  1   4.7   2.6 |  19.7  67.5  245   1  0   8.0   4.4
  7500  19.2  66.6  110   3  1   4.4   2.4 |  20.3  68.5  225   1  0   8.1   4.5
  7250  19.5  67.1  120   3  2   3.9   2.1 |  20.9  69.6  215   1  1   8.1   4.5
  7000  19.7  67.5  125   4  2   4.8   2.6 |  21.5  70.7  205   1  1   8.2   4.5
  6750  20.1  68.2  130   5  2   3.8   2.1 |  22.2  72.0  200   1  1   9.6   5.3
  6500  20.2  68.4  130   5  3   0.9   0.5 |  22.9  73.2  205   1  1  10.9   6.0
  6250  20.1  68.2  130   5  3  -0.5  -0.3 |  23.7  74.7  205   2  1  10.6   5.8
  6000  20.1  68.2  130   5  2   1.9   1.1 |  24.6  76.3  210   2  1  11.3   6.2
  5750  20.4  68.7  130   5  3   9.4   5.2 |  25.5  77.9  210   2  1  17.2   9.5
  5500  21.3  70.3  130   5  2  15.4   8.4 |  27.1  80.8  215   2  1  25.0  13.7
  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

           08/16/2014 at 1500 MDT          |       08/16/2014 at 1800 MDT
                                           |
K index... +15.2  LI... -0.9               | K index... +23.2  LI... +0.8
CAPE... +388.0  CIN... -22.5               | CAPE... +133.0  CIN... -107.2
                                           |
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 -65.2 -85.4  295  26 13   0.0   0.0 | -65.1 -85.2  285  23 12   0.4   0.2
 45000 -62.3 -80.1  295  40 21   6.2   3.4 | -61.9 -79.4  285  33 17   5.9   3.2
 40000 -52.3 -62.1  285  36 18   7.1   3.9 | -52.3 -62.1  275  34 17   7.4   4.1
 38000 -48.0 -54.4  285  33 17   7.1   3.9 | -47.8 -54.0  275  32 17   7.4   4.1
 36000 -43.7 -46.7  285  30 16   7.1   3.9 | -43.4 -46.1  280  31 16   7.2   3.9
 34000 -39.6 -39.3  285  25 13   6.8   3.8 | -39.4 -38.9  280  26 13   6.7   3.7
 32000 -35.5 -31.9  285  20 10   6.9   3.8 | -35.4 -31.7  275  20 10   6.7   3.7
 30000 -31.0 -23.8  285  18  9   7.6   4.2 | -31.0 -23.8  285  19 10   7.5   4.1
 29000 -28.7 -19.7  290  17  9   7.6   4.2 | -28.7 -19.7  285  18  9   7.5   4.1
 28000 -25.8 -14.4  295  16  8   7.6   4.2 | -25.9 -14.6  295  18  9   7.4   4.1
 27000 -23.6 -10.5  300  17  9   7.6   4.2 | -23.7 -10.7  300  18  9   7.4   4.1
 26000 -21.3  -6.3  305  18  9   7.6   4.2 | -21.5  -6.7  305  18  9   7.4   4.1
 25000 -19.0  -2.2  310  18  9   7.5   4.1 | -19.2  -2.6  310  19 10   7.9   4.3
 24000 -16.8   1.8  310  18  9   7.5   4.1 | -16.8   1.8  315  19 10   8.1   4.4
 23000 -14.5   5.9  310  17  9   7.5   4.1 | -14.4   6.1  320  19 10   8.1   4.4
 22000 -12.3   9.9  310  17  9   7.7   4.2 | -12.0  10.4  325  19 10   8.0   4.4
 21000 -10.0  14.0  310  16  8   7.7   4.2 |  -9.6  14.7  325  18  9   7.9   4.4
 20000  -7.7  18.1  310  15  8   7.7   4.2 |  -7.2  19.0  325  17  9   7.9   4.3
 19500  -6.5  20.3  310  15  8   7.0   3.8 |  -6.1  21.0  320  16  8   7.5   4.1
 19000  -5.7  21.7  310  14  7   5.3   2.9 |  -5.1  22.8  320  16  8   6.6   3.6
 18500  -4.9  23.2  310  13  7   5.3   2.9 |  -4.1  24.6  325  15  8   6.7   3.7
 18000  -4.0  24.8  310  12  6   7.4   4.1 |  -3.2  26.2  325  15  8   5.8   3.2
 17500  -2.9  26.8  310  12  6   7.7   4.2 |  -2.4  27.7  330  14  7   5.9   3.2
 17000  -1.7  28.9  310  11  6   7.5   4.1 |  -1.6  29.1  335  13  7   6.5   3.6
 16500  -0.7  30.7  315  10  5   7.0   3.8 |  -0.6  30.9  340  12  6   7.9   4.3
 16000   0.3  32.5  315  10  5   7.0   3.8 |   0.5  32.9  345  11  6   7.8   4.3
 15500   1.4  34.5  315  10  5   8.3   4.5 |   1.6  34.9  345  10  5   8.9   4.9
 15000   2.5  36.5  315  10  5   8.2   4.5 |   2.9  37.2  350   9  5   8.9   4.9
 14500   3.7  38.7  315  10  5   8.4   4.6 |   4.2  39.6  350   9  4   9.2   5.0
 14000   4.9  40.8  310   9  5   8.5   4.7 |   5.5  41.9  350   8  4   9.3   5.1
 13500   6.8  44.2  305   9  4   9.0   4.9 |   7.5  45.5  350   7  3   8.8   4.8
 13000   8.1  46.6  305   8  4   9.0   4.9 |   8.8  47.8  350   6  3   8.8   4.8
 12500   9.4  48.9  300   8  4   8.7   4.8 |  10.1  50.2  350   5  3   8.8   4.8
 12000  10.6  51.1  300   7  4   8.6   4.7 |  11.5  52.7  345   5  3   8.8   4.8
 11500  11.9  53.4  300   6  3   8.8   4.8 |  12.8  55.0  345   5  2   8.7   4.8
 11000  13.2  55.8  295   6  3   9.2   5.0 |  14.1  57.4  345   4  2   8.9   4.9
 10500  14.3  57.7  295   5  3   5.4   3.0 |  15.2  59.4  345   4  2   5.4   3.0
 10250  14.8  58.6  290   5  3   9.1   5.0 |  15.7  60.3  340   4  2   8.6   4.7
 10000  15.6  60.1  290   5  2  11.5   6.3 |  16.4  61.5  340   3  2  11.1   6.1
  9750  16.4  61.5  290   4  2  10.5   5.7 |  17.2  63.0  335   3  2  10.5   5.7
  9500  17.0  62.6  290   4  2   7.6   4.1 |  17.9  64.2  330   3  2   7.5   4.1
  9250  17.5  63.5  290   4  2   7.7   4.2 |  18.4  65.1  325   3  1   7.1   3.9
  9000  18.2  64.8  290   4  2  10.0   5.5 |  19.1  66.4  320   3  1   9.4   5.1
  8750  18.9  66.0  285   4  2   9.6   5.2 |  19.7  67.5  315   2  1   8.8   4.8
  8500  19.6  67.3  285   4  2   9.5   5.2 |  20.4  68.7  310   2  1   8.3   4.6
  8250  20.2  68.4  285   4  2   9.6   5.2 |  21.0  69.8  300   2  1   7.9   4.4
  8000  20.8  69.4  280   3  2   9.8   5.4 |  21.5  70.7  295   2  1   8.0   4.4
  7750  21.5  70.7  280   3  2  10.0   5.5 |  22.1  71.8  290   2  1   8.2   4.5
  7500  22.2  72.0  280   3  2  10.0   5.5 |  22.7  72.9  285   2  1   8.6   4.7
  7250  23.0  73.4  275   3  2  10.2   5.6 |  23.3  73.9  280   2  1   8.9   4.9
  7000  23.7  74.7  275   3  2   9.4   5.2 |  23.9  75.0  275   2  1   8.5   4.7
  6750  24.4  75.9  275   3  2  10.2   5.6 |  24.5  76.1  275   2  1   9.4   5.2
  6500  25.2  77.4  270   3  2  11.4   6.2 |  25.3  77.5  270   2  1  10.7   5.8
  6250  26.1  79.0  270   4  2  11.2   6.1 |  26.1  79.0  265   2  1  10.8   5.9
  6000  26.9  80.4  270   4  2  10.7   5.9 |  26.9  80.4  265   2  1   9.9   5.4
  5750  27.7  81.9  265   3  2  12.5   6.9 |  27.5  81.5  260   2  1   9.4   5.2
  5500  28.7  83.7  270   3  2  14.9   8.2 |  28.3  82.9  265   2  1  10.2   5.6
  5250  29.7  85.5  270   3  2  13.1   7.2 |  29.0  84.2  270   2  1   9.5   5.2
  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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