Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291300
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0700 MDT Saturday, August 29, 2015

This forecast is for Saturday, August 29, 2015:

If the trigger temperature of 83.9 F/28.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 976 ft/min (5.0 m/s)
   Maximum height of thermals.................. 15739 ft MSL (10900 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1315 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................. 10090 ft MSL (5251 ft AGL)
Thermal soaring outlook for Sunday 08/30....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:39:55 / 19:50:54 MDT
Total possible sunshine........... 13 hr 10 min 59 sec (790 min 59 sec)
Altitude of sun at 13:14:59 MDT... 60.14 degrees

Upper air data from rawinsonde observation taken on 08/29/2015 at 0600 MDT

Freezing level.................. 15778 ft MSL (10939 ft AGL)
Convective condensation level... 16952 ft MSL (12113 ft AGL)
Lifted condensation level....... 16844 ft MSL (12005 ft AGL)
Lifted index.................... +1.4
K index......................... +5.0

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  -63.2 -81.8   330   19   10  -1.1  -0.6   89.3 192.8    32.8      M    M
 45000  -65.3 -85.5   340   39   20   2.0   1.1   61.2 142.1    17.7      M    M
 40000  -54.8 -66.6   360   29   15   2.3   1.2   54.7 130.5    14.6      M    M
 38000  -51.2 -60.2   345   20   10   9.2   5.1   51.3 124.4    12.7      M    M
 36000  -45.7 -50.3   355   13    7   9.2   5.1   50.9 123.6    12.7      M    M
 34000  -39.9 -39.8   355    5    3   8.5   4.7   49.9 121.8    12.4      M    M
 32000  -34.8 -30.6   360   11    5   8.6   4.7   48.8 119.8    11.9      M    M
 30000  -30.7 -23.3   330   10    5   7.6   4.2   46.5 115.6    10.4      M    M
 29000  -28.3 -18.9   330    9    5   8.2   4.5   45.7 114.3    10.0      M    M
 28000  -25.8 -14.4   325    9    4   8.2   4.5   45.2 113.3     9.6      M    M
 27000  -23.3  -9.9   320    8    4   9.0   4.9   44.7 112.4     9.3      M    M
 26000  -20.6  -5.1   320    8    4   8.9   4.9   44.3 111.8     9.2      M    M
 25000  -18.0  -0.4   315    7    4   8.4   4.6   44.1 111.3     9.0      M    M
 24000  -15.6   3.9   310    7    4   7.8   4.3   43.3 109.9     8.5      M    M
 23000  -13.3   8.1   305    8    4   7.8   4.3   42.6 108.6     8.0      M    M
 22000  -11.0  12.2   300    8    4   6.4   3.5   41.9 107.4     7.5      M    M
 21000   -9.1  15.6   295    8    4   6.7   3.7   40.6 105.1     6.6      M    M
 20000   -8.5  16.7   290    9    5   4.4   2.4   37.9 100.3     4.3      M    M
 19500   -7.7  18.1   285   10    5   6.5   3.6   37.2  99.0     3.7      M    M
 19000   -7.9  17.8   280   10    5  -5.0  -2.7   35.3  95.6     2.0      M    M
 18500   -6.7  19.9   265    9    4   7.4   4.1   34.2  93.5     1.0      M    M
 18000   -5.5  22.1   255    9    4   8.5   4.7   33.8  92.9     0.8      M    M
 17500   -4.2  24.4   240    9    5   8.9   4.9   33.7  92.6     0.6      M    M
 17000   -2.8  27.0   230    9    5   9.0   4.9   33.5  92.3     0.5      M    M
 16500   -1.5  29.3   220   10    5   9.0   4.9   33.4  92.1     0.4      M    M
 16000   -0.2  31.6   215   11    6   6.7   3.7   33.2  91.8     0.2      M    M
 15500    0.9  33.6   215    9    5   9.4   5.1   32.9  91.1    -0.2    943  4.8
 15000    2.2  36.0   215    7    4   9.0   4.9   32.7  90.9    -0.3    888  4.5
 14500    3.6  38.5   215    6    3   9.1   5.0   32.6  90.7    -0.4    833  4.2
 14000    4.8  40.6   215    4    2   7.3   4.0   32.4  90.3    -0.6    781  4.0
 13500    5.8  42.4   190    3    2   7.6   4.2   32.0  89.6    -1.1    736  3.7
 13000    6.7  44.1   155    3    2   6.8   3.7   31.6  88.9    -1.6    694  3.5
 12500    7.7  45.9   130    4    2   9.7   5.3   31.3  88.4    -2.2    651  3.3
 12000    9.2  48.6   115    5    3   9.6   5.2   31.3  88.3    -2.1    591  3.0
 11500   10.7  51.3   110    5    2   9.8   5.4   31.3  88.3    -2.1    531  2.7
 11000   11.9  53.4   110    4    2   7.2   3.9   31.1  87.9    -2.3    478  2.4
 10500   13.0  55.4   105    4    2   7.7   4.2   30.7  87.3    -2.7    432  2.2
 10250   13.6  56.5   125    5    2   8.0   4.4   30.5  87.0    -2.9    407  2.1
 10000   14.1  57.4   135    6    3   8.0   4.4   30.4  86.7    -3.1    382  1.9
  9750   14.7  58.5   145    7    4   8.0   4.4   30.3  86.5    -3.2    358  1.8
  9500   15.3  59.5   150    9    5   8.0   4.4   30.1  86.2    -3.4    333  1.7
  9250   15.9  60.6   150   10    5   8.0   4.4   30.0  86.0    -3.5    308  1.6
  9000   16.4  61.5   155   12    6   8.1   4.4   29.9  85.8    -3.7    284  1.4
  8750   17.0  62.6   155   10    5   7.7   4.2   29.7  85.5    -3.8    259  1.3
  8500   17.5  63.5   155    8    4   5.4   3.0   29.5  85.1    -4.1    237  1.2
  8250   17.8  64.0   155    6    3   4.1   2.3   29.1  84.3    -4.5    220  1.1
  8000   18.1  64.6   155    3    2   4.2   2.3   28.7  83.6    -5.0    203  1.0
  7750   18.4  65.1   130    4    2   5.1   2.8   28.2  82.8    -5.4    187  0.9
  7500   18.8  65.8   115    5    3   1.5   0.8   27.8  82.1    -5.8    170  0.9
  7250   18.7  65.7   105    7    4  -0.1  -0.1   27.0  80.6    -6.6    165  0.8
  7000   18.9  66.0   100    9    4   5.3   2.9   26.5  79.7    -7.2    152  0.8
  6750   19.3  66.7   100    9    5   6.7   3.7   26.2  79.2    -7.5    131  0.7
  6500   19.8  67.6   100    9    4   6.3   3.4   26.0  78.7    -7.8    109  0.6
  6250   20.3  68.5   100    8    4   6.8   3.7   25.7  78.3    -8.0     88  0.4
  6000   20.7  69.3   100    8    4   5.3   2.9   25.5  77.8    -8.3     66  0.3
  5750   20.9  69.6   100    8    4  -0.4  -0.2   24.9  76.9    -8.9     53  0.3
  5500   20.7  69.3   100    8    4  -2.4  -1.3   24.0  75.2    -9.8     52  0.3
  5250   20.5  68.9   105    7    4  -3.8  -2.1   23.1  73.6   -10.8     51  0.3
  5000   19.7  67.5   105    7    4 -20.2 -11.1   21.6  70.9   -12.4     69  0.3

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

           08/29/2015 at 0900 MDT          |       08/29/2015 at 1200 MDT
                                           |
K index... +20.0  LI... +272.5             | K index... +20.9  LI... +271.2
CAPE... +26.8  CIN... -29.2                | CAPE... +388.7  CIN... -32.0
                                           |
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 -66.8 -88.2  320  20 10  -0.6  -0.3 | -67.2 -89.0  315  21 11  -0.8  -0.4
 45000 -64.3 -83.7  335  28 15   6.7   3.7 | -64.3 -83.7  330  29 15   7.4   4.0
 40000 -54.1 -65.4  335  24 12   7.2   4.0 | -53.3 -63.9  335  23 12   7.2   4.0
 38000 -49.8 -57.6  340  14  7   7.2   4.0 | -49.0 -56.2  330  17  9   7.2   4.0
 36000 -45.4 -49.7  345   5  2   7.3   4.0 | -44.6 -48.3  315  11  6   7.4   4.0
 34000 -39.6 -39.3  340   3  1   8.7   4.8 | -39.0 -38.2  305   6  3   8.4   4.6
 32000 -34.4 -29.9  330   2  1   8.5   4.7 | -34.0 -29.2  270   2  1   8.2   4.5
 30000 -29.8 -21.6  335   1  1   7.5   4.1 | -29.4 -20.9  210   2  1   7.6   4.2
 29000 -27.6 -17.7  345   1  1   7.5   4.1 | -27.1 -16.8  190   3  1   7.6   4.2
 28000 -25.3 -13.5  345   1  1   7.7   4.2 | -24.9 -12.8  180   3  2   7.5   4.1
 27000 -23.0  -9.4  330   1  1   7.7   4.2 | -22.6  -8.7  185   4  2   7.5   4.1
 26000 -20.7  -5.3  320   2  1   7.7   4.2 | -20.4  -4.7  190   4  2   7.5   4.1
 25000 -18.4  -1.1  310   2  1   7.8   4.3 | -18.1  -0.6  195   4  2   7.7   4.2
 24000 -16.1   3.0  330   2  1   7.9   4.3 | -15.8   3.6  200   3  1   7.8   4.3
 23000 -13.7   7.3  340   3  2   7.9   4.4 | -13.5   7.7  210   2  1   7.9   4.3
 22000 -11.4  11.5  350   4  2   6.3   3.5 | -11.2  11.8  240   1  1   6.4   3.5
 21000 -10.0  14.0  345   4  2   4.6   2.5 |  -9.6  14.7  205   1  1   5.1   2.8
 20000  -8.6  16.5  340   3  2   4.6   2.5 |  -8.1  17.4  185   2  1   5.1   2.8
 19500  -7.5  18.5  335   3  2   4.9   2.7 |  -6.9  19.6  180   2  1   5.0   2.8
 19000  -6.8  19.8  315   3  1   5.1   2.8 |  -6.2  20.8  185   3  2   5.0   2.7
 18500  -6.1  21.0  290   3  1   5.0   2.8 |  -5.5  22.1  190   4  2   4.9   2.7
 18000  -5.2  22.6  270   3  2   7.2   3.9 |  -4.6  23.7  195   4  2   6.7   3.7
 17500  -4.2  24.4  255   4  2   7.0   3.8 |  -3.6  25.5  205   5  3   6.6   3.6
 17000  -3.1  26.4  245   5  3   7.4   4.1 |  -2.7  27.1  210   6  3   6.8   3.7
 16500  -2.0  28.4  240   6  3   7.7   4.2 |  -1.7  28.9  220   6  3   7.1   3.9
 16000  -0.9  30.4  235   7  4   7.9   4.4 |  -0.8  30.6  225   7  4   7.5   4.1
 15500   0.2  32.4  235   8  4   8.7   4.8 |   0.3  32.5  230   8  4   8.4   4.6
 15000   1.5  34.7  235   8  4   8.8   4.8 |   1.5  34.7  230   8  4   8.4   4.6
 14500   2.7  36.9  230   8  4   8.8   4.8 |   2.7  36.9  235   8  4   8.6   4.7
 14000   4.0  39.2  230   8  4   8.8   4.8 |   3.9  39.0  235   7  4   8.7   4.8
 13500   5.2  41.4  225   8  4   8.8   4.8 |   5.2  41.4  240   7  4   8.4   4.6
 13000   6.5  43.7  225   8  4   8.9   4.9 |   6.4  43.5  240   7  4   8.3   4.6
 12500   7.7  45.9  220   7  4   8.6   4.7 |   7.6  45.7  235   7  3   8.2   4.5
 12000   9.0  48.2  215   7  4   8.4   4.6 |   8.8  47.8  235   7  3   8.2   4.5
 11500  10.2  50.4  210   7  4   8.3   4.6 |   9.9  49.8  230   6  3   8.3   4.6
 11000  11.3  52.3  205   8  4   8.1   4.5 |  11.2  52.2  225   7  4   8.1   4.5
 10500  12.5  54.5  200   9  5   6.6   3.6 |  12.4  54.3  220   8  4   3.4   1.9
 10250  12.9  55.2  200  10  5   6.8   3.7 |  12.5  54.5  220   8  4   5.3   2.9
 10000  13.5  56.3  195  10  5   9.1   5.0 |  13.3  55.9  220   9  4  12.8   7.0
  9750  14.2  57.6  195  11  6   8.9   4.9 |  14.1  57.4  225   9  5  11.3   6.2
  9500  14.8  58.6  190  12  6   8.0   4.4 |  14.9  58.8  225  10  5   8.8   4.8
  9250  15.3  59.5  190  13  7   6.9   3.8 |  15.4  59.7  225  10  5   6.5   3.6
  9000  15.8  60.4  185  14  7   7.0   3.8 |  15.9  60.6  225  10  5   9.3   5.1
  8750  16.4  61.5  185  15  8   6.9   3.8 |  16.6  61.9  220  10  5  10.2   5.6
  8500  16.8  62.2  180  16  8   5.9   3.2 |  17.3  63.1  220  10  5   8.5   4.7
  8250  17.2  63.0  180  16  8   4.9   2.7 |  17.8  64.0  220   9  5   7.4   4.0
  8000  17.6  63.7  175  17  9   5.5   3.0 |  18.3  64.9  215   9  5   8.4   4.6
  7750  18.0  64.4  175  17  9   5.3   2.9 |  18.9  66.0  215   8  4   9.3   5.1
  7500  18.3  64.9  175  17  9   3.4   1.9 |  19.6  67.3  210   8  4   9.6   5.3
  7250  18.5  65.3  170  17  9   2.3   1.3 |  20.3  68.5  210   8  4   9.7   5.3
  7000  18.7  65.7  165  16  8   3.4   1.8 |  21.1  70.0  210   8  4   9.7   5.3
  6750  18.9  66.0  160  16  8   2.4   1.3 |  21.8  71.2  210   8  4  10.2   5.6
  6500  19.0  66.2  160  14  7   0.2   0.1 |  22.6  72.7  210   7  4  10.6   5.8
  6250  19.0  66.2  155  11  6  -0.3  -0.2 |  23.4  74.1  210   7  4  10.6   5.8
  6000  18.9  66.0  145   9  5   1.1   0.6 |  24.1  75.4  215   7  4  10.4   5.7
  5750  19.2  66.6  140   8  4   7.9   4.4 |  25.1  77.2  215   7  4  16.8   9.2
  5500  20.1  68.2  135   7  4  15.1   8.3 |  26.7  80.1  215   7  4  27.9  15.3
  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

           08/29/2015 at 1500 MDT          |       08/29/2015 at 1800 MDT
                                           |
K index... +32.2  LI... +271.1             | K index... +30.2  LI... +272.0
CAPE... +385.7  CIN... -19.5               | CAPE... +113.9  CIN... -53.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -67.0 -88.6  295  20 10  -0.9  -0.5 | -67.8 -90.0  295  18  9  -0.7  -0.4
 45000 -64.2 -83.6  315  26 14   7.3   4.0 | -64.6 -84.3  315  23 12   7.7   4.2
 40000 -53.2 -63.8  325  23 12   7.7   4.2 | -52.9 -63.2  315  24 12   8.3   4.6
 38000 -48.5 -55.3  320  19 10   7.7   4.2 | -47.9 -54.2  315  18  9   8.3   4.6
 36000 -43.9 -47.0  310  15  8   7.7   4.2 | -42.9 -45.2  315  12  6   8.2   4.5
 34000 -39.2 -38.6  295  10  5   7.9   4.3 | -38.2 -36.8  300  10  5   7.8   4.3
 32000 -33.8 -28.8  255   6  3   7.9   4.3 | -33.6 -28.5  275   9  5   7.7   4.2
 30000 -29.2 -20.6  220   7  3   7.6   4.2 | -28.4 -19.1  245   9  5   7.7   4.2
 29000 -27.0 -16.6  210   8  4   7.6   4.2 | -26.1 -15.0  230  10  5   7.7   4.2
 28000 -24.7 -12.5  205   9  4   7.4   4.1 | -23.9 -11.0  225  11  6   6.9   3.8
 27000 -22.5  -8.5  205   8  4   7.4   4.1 | -21.8  -7.2  230  11  6   7.0   3.8
 26000 -20.2  -4.4  205   8  4   7.4   4.1 | -19.7  -3.5  230  12  6   7.0   3.8
 25000 -18.0  -0.4  205   8  4   7.6   4.2 | -17.7   0.1  235  12  6   7.3   4.0
 24000 -15.7   3.7  205   7  3   7.8   4.3 | -15.4   4.3  235  11  5   7.6   4.2
 23000 -13.4   7.9  205   5  3   7.8   4.3 | -13.1   8.4  235   9  5   7.6   4.2
 22000 -11.1  12.0  210   4  2   6.1   3.4 | -10.9  12.4  240   8  4   6.3   3.5
 21000  -9.5  14.9  210   6  3   5.5   3.0 |  -9.3  15.3  240   8  4   5.7   3.1
 20000  -7.9  17.8  210   7  4   5.5   3.0 |  -7.6  18.3  245   8  4   5.8   3.2
 19500  -7.1  19.2  215   8  4   5.6   3.1 |  -6.8  19.8  245   8  4   5.9   3.2
 19000  -6.3  20.7  215   9  5   6.0   3.3 |  -5.9  21.4  240   9  5   6.5   3.6
 18500  -5.5  22.1  215  10  5   6.0   3.3 |  -5.0  23.0  240  10  5   6.5   3.6
 18000  -4.6  23.7  215  11  6   7.7   4.2 |  -4.1  24.6  240  11  6   6.4   3.5
 17500  -3.5  25.7  215  11  6   8.3   4.6 |  -3.2  26.2  235  13  6   6.4   3.5
 17000  -2.3  27.9  220  11  6   8.3   4.6 |  -2.3  27.9  235  14  7   6.8   3.7
 16500  -1.2  29.8  220  11  6   7.5   4.1 |  -1.1  30.0  235  14  7   9.1   5.0
 16000  -0.2  31.6  225  11  6   7.8   4.3 |   0.1  32.2  235  15  8   9.0   5.0
 15500   0.8  33.4  225  11  6   6.4   3.5 |   1.4  34.5  235  15  8   8.3   4.5
 15000   2.1  35.8  225  11  5   6.4   3.5 |   2.5  36.5  235  14  7   8.2   4.5
 14500   3.1  37.6  230  10  5   7.7   4.2 |   4.3  39.7  235  14  7   7.9   4.4
 14000   4.2  39.6  230  10  5   7.5   4.1 |   5.5  41.9  235  13  7   8.0   4.4
 13500   5.4  41.7  230   9  5   8.3   4.6 |   6.6  43.9  235  12  6   8.2   4.5
 13000   6.6  43.9  230   9  5   8.3   4.6 |   7.8  46.0  235  11  6   8.2   4.5
 12500   7.8  46.0  230   9  5   8.7   4.8 |   9.1  48.4  235  10  5   8.4   4.6
 12000   9.1  48.4  230   8  4   8.8   4.8 |  10.3  50.5  235   9  5   8.5   4.7
 11500  10.4  50.7  235   8  4   8.8   4.8 |  11.6  52.9  240   8  4   8.8   4.8
 11000  11.7  53.1  235   7  4   9.1   5.0 |  13.0  55.4  240   8  4   9.0   4.9
 10500  12.9  55.2  235   7  4   4.4   2.4 |  14.2  57.6  245   7  4   5.6   3.1
 10250  13.2  55.8  235   7  3   7.7   4.2 |  14.6  58.3  245   6  3   7.4   4.1
 10000  14.0  57.2  240   6  3  11.4   6.2 |  15.4  59.7  245   6  3  11.4   6.2
  9750  14.9  58.8  240   6  3  10.3   5.6 |  16.2  61.2  250   5  3  10.7   5.8
  9500  15.6  60.1  245   6  3   8.8   4.8 |  16.9  62.4  250   5  3   8.1   4.4
  9250  16.2  61.2  245   6  3   9.2   5.0 |  17.4  63.3  250   4  2   7.0   3.9
  9000  17.0  62.6  245   6  3  11.1   6.1 |  18.0  64.4  250   4  2   9.0   5.0
  8750  17.8  64.0  245   5  3  10.8   5.9 |  18.7  65.7  250   3  2   8.7   4.8
  8500  18.5  65.3  250   5  3  10.1   5.5 |  19.3  66.7  250   3  1   7.9   4.3
  8250  19.3  66.7  250   5  3   9.8   5.4 |  19.8  67.6  250   2  1   7.3   4.0
  8000  20.0  68.0  250   5  3  10.0   5.5 |  20.4  68.7  245   2  1   7.7   4.2
  7750  20.8  69.4  250   5  3   9.9   5.4 |  20.9  69.6  245   1  1   7.5   4.1
  7500  21.5  70.7  250   5  3   9.8   5.4 |  21.5  70.7  240   1  0   7.0   3.8
  7250  22.2  72.0  250   5  3   9.7   5.3 |  22.0  71.6  240   1  0   6.7   3.7
  7000  23.0  73.4  250   6  3  10.0   5.5 |  22.5  72.5  000   0  0   7.1   3.9
  6750  23.7  74.7  250   5  3  10.7   5.9 |  23.0  73.4  000   0  0   8.7   4.8
  6500  24.6  76.3  250   5  3  11.0   6.0 |  23.7  74.7  000   0  0   9.8   5.4
  6250  25.4  77.7  250   5  3  11.0   6.0 |  24.5  76.1  000   0  0  10.1   5.6
  6000  26.2  79.2  250   5  3  10.6   5.8 |  25.2  77.4  000   0  0   8.8   4.8
  5750  27.0  80.6  250   5  3  12.8   7.0 |  25.8  78.4  000   0  0   7.9   4.4
  5500  28.1  82.6  250   5  3  15.3   8.4 |  26.4  79.5  255   1  0   8.8   4.9
  5250  29.1  84.4  255   5  3  13.3   7.3 |  27.1  80.8  255   1  0   8.1   4.4
  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 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  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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