Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 031247
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0647 MDT Friday, July 3, 2015

This forecast is for Friday, July 3, 2015:

If the trigger temperature of 86.8 F/30.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1376 ft/min (7.0 m/s)
   Maximum height of thermals.................. 17707 ft MSL (12868 ft AGL)

Forecast maximum temperature................... 96.0 F/36.0 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................. 11371 ft MSL (6532 ft AGL)
Thermal soaring outlook for Saturday 07/04..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:52:53 / 20:43:49 MDT
Total possible sunshine........... 14 hr 50 min 56 sec (890 min 56 sec)
Altitude of sun at 13:18:23 MDT... 73.79 degrees

Upper air data from rawinsonde observation taken on 07/03/2015 at 0600 MDT

Freezing level.................. 16482 ft MSL (11643 ft AGL)
Convective condensation level... 15872 ft MSL (11033 ft AGL)
Lifted condensation level....... 16298 ft MSL (11459 ft AGL)
Lifted index.................... -2.7
K index......................... +25.6

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  -70.0 -94.0   320   39   20  -3.5  -1.9   76.8 170.2    23.9      M    M
 45000  -64.8 -84.6   290   45   23   8.9   4.9   60.8 141.5    15.8      M    M
 40000  -51.3 -60.3   290   48   25   7.2   4.0   58.2 136.8    15.2      M    M
 38000  -46.1 -51.0   300   43   22   9.1   5.0   57.4 135.3    15.0      M    M
 36000  -41.3 -42.3   310   40   21   9.6   5.3   55.9 132.6    14.3      M    M
 34000  -37.6 -35.7   315   33   17   8.7   4.7   52.9 127.2    12.5      M    M
 32000  -32.5 -26.5   310   32   17   6.7   3.7   51.9 125.3    12.0      M    M
 30000  -26.5 -15.7   310   29   15   8.7   4.7   51.1 124.0    11.8      M    M
 29000  -24.0 -11.2   305   27   14   9.0   4.9   50.5 123.0    11.5      M    M
 28000  -21.6  -6.9   305   26   13   6.0   3.3   50.0 122.0    11.2      M    M
 27000  -19.8  -3.6   315   25   13   5.2   2.8   48.6 119.4    10.2      M    M
 26000  -18.3  -0.9   325   25   13   6.8   3.7   46.6 115.9     8.8      M    M
 25000  -16.3   2.7   335   26   13   5.7   3.1   45.6 114.0     8.0      M    M
 24000  -15.4   4.3   340   24   12   6.0   3.3   43.1 109.6     6.1      M    M
 23000  -12.9   8.8   350   22   11   8.4   4.6   42.6 108.7     5.7      M    M
 22000  -10.5  13.1   360   21   11   4.8   2.6   42.0 107.6     5.3      M    M
 21000  -10.8  12.6   350   17    9   4.9   2.7   38.5 101.3     2.1      M    M
 20000   -8.4  16.9   330   13    7   8.6   4.7   37.9 100.2     1.6      M    M
 19500   -7.2  19.0   315   14    7   8.6   4.7   37.7  99.9     1.4      M    M
 19000   -5.9  21.4   310   15    7   8.8   4.8   37.5  99.5     1.2      M    M
 18500   -4.6  23.7   305   14    7   8.2   4.5   37.4  99.2     1.0      M    M
 18000   -3.7  25.3   300   13    7   6.1   3.3   36.8  98.3     0.5      M    M
 17500   -2.8  27.0   300   13    6   7.4   4.1   36.2  97.2    -0.1   1168  5.9
 17000   -1.6  29.1   295   12    6   8.3   4.5   36.0  96.8    -0.4   1117  5.7
 16500    0.3  32.5   290   11    6   9.1   5.0   35.7  96.3    -0.7   1039  5.3
 16000    1.6  34.9   290   11    6   9.1   5.0   35.6  96.1    -0.7    983  5.0
 15500    3.0  37.4   300   13    7   9.1   5.0   35.5  95.9    -0.8    928  4.7
 15000    4.3  39.7   305   14    7   9.1   5.0   35.4  95.8    -0.9    872  4.4
 14500    5.7  42.3   310   14    7   9.1   5.0   35.3  95.6    -1.0    817  4.2
 14000    7.0  44.6   310   14    7   9.1   5.0   35.2  95.4    -1.1    762  3.9
 13500    8.4  47.1   310   13    7   9.1   5.0   35.1  95.2    -1.3    706  3.6
 13000    9.8  49.6   310   13    7   9.1   5.0   35.0  95.0    -1.4    651  3.3
 12500   11.1  52.0   290   12    6   7.3   4.0   34.8  94.7    -1.6    597  3.0
 12000   11.9  53.4   275   13    7   6.2   3.4   34.2  93.6    -2.2    558  2.8
 11500   12.7  54.9   275   13    7   6.0   3.3   33.6  92.5    -2.9    518  2.6
 11000   13.6  56.5   275   13    7   7.9   4.3   33.2  91.7    -3.4    475  2.4
 10500   14.8  58.6   275   13    7   7.8   4.3   32.9  91.2    -3.7    426  2.2
 10250   15.4  59.7   275   13    6   7.6   4.2   32.7  90.9    -3.9    401  2.0
 10000   15.9  60.6   280   12    6   7.6   4.2   32.6  90.6    -4.1    378  1.9
  9750   16.5  61.7   280   12    6   7.6   4.2   32.4  90.3    -4.3    354  1.8
  9500   17.0  62.6   285   11    6   7.6   4.2   32.2  90.0    -4.4    330  1.7
  9250   17.6  63.7   285   10    5   7.6   4.2   32.1  89.7    -4.6    306  1.6
  9000   18.1  64.6   290   10    5   7.8   4.3   31.9  89.5    -4.8    282  1.4
  8750   18.7  65.7   285    8    4   7.1   3.9   31.7  89.1    -5.0    258  1.3
  8500   19.2  66.6   275    6    3   9.7   5.3   31.6  88.8    -5.2    234  1.2
  8250   19.8  67.6   260    4    2  -0.0  -0.0   31.4  88.5    -5.4    211  1.1
  8000   19.4  66.9   225    3    2  -1.4  -0.8   30.3  86.5    -6.5    215  1.1
  7750   19.9  67.8   205    4    2  10.9   6.0   30.0  86.1    -6.8    193  1.0
  7500   20.7  69.3   190    5    2  11.2   6.2   30.2  86.3    -6.7    161  0.8
  7250   21.5  70.7   180    6    3  11.1   6.1   30.3  86.5    -6.6    130  0.7
  7000   22.3  72.1   175    7    3  11.3   6.2   30.4  86.7    -6.5     98  0.5
  6750   23.1  73.6   160    8    4  10.6   5.8   30.5  86.9    -6.5     67  0.3
  6500   23.9  75.0   145   10    5  13.4   7.4   30.6  87.1    -6.4     35  0.2
  6250   24.7  76.5   135   12    6   2.9   1.6   30.7  87.3    -6.4      3  0.0
  6000   24.4  75.9   130   14    7  -7.9  -4.4   29.6  85.2    -7.5      7  0.0
  5750   24.1  75.4   125   14    7   2.2   1.2   28.6  83.4    -8.4      6  0.0
  5500   24.6  76.3   120   12    6   8.2   4.5   28.3  83.0    -8.7      M    M
  5250   25.1  77.2   110   11    5   3.4   1.9   28.1  82.5    -8.9      M    M
  5000   25.0  77.0   100   10    5  -8.7  -4.7   27.2  80.9    -9.8      M    M

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

           07/03/2015 at 0900 MDT          |       07/03/2015 at 1200 MDT
                                           |
K index... +29.7  LI... +269.7             | K index... +29.9  LI... +267.9
CAPE... +511.6  CIN... -93.5               | CAPE... +1310.7  CIN... -38.5
                                           |
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 -67.2 -89.0  315  28 14  -0.2  -0.1 | -67.5 -89.5  315  26 13  -0.1  -0.0
 45000 -63.5 -82.3  310  46 24   8.0   4.4 | -63.8 -82.8  310  43 22   7.8   4.3
 40000 -51.0 -59.8  305  49 25   7.6   4.2 | -51.4 -60.5  310  43 22   8.2   4.5
 38000 -46.5 -51.7  315  43 22   7.6   4.2 | -46.5 -51.7  315  37 19   8.2   4.5
 36000 -41.9 -43.4  325  39 20   7.8   4.3 | -41.6 -42.9  330  32 17   8.0   4.4
 34000 -37.1 -34.8  325  35 18   8.0   4.4 | -36.9 -34.4  335  29 15   7.8   4.3
 32000 -32.3 -26.1  325  32 16   8.3   4.5 | -32.2 -26.0  340  26 13   8.0   4.4
 30000 -27.4 -17.3  330  28 14   8.2   4.5 | -27.5 -17.5  335  22 11   7.9   4.3
 29000 -24.3 -11.7  330  26 13   8.2   4.5 | -24.5 -12.1  335  19 10   7.9   4.3
 28000 -22.1  -7.8  330  24 12   5.6   3.1 | -22.2  -8.0  335  18  9   6.9   3.8
 27000 -20.4  -4.7  330  22 11   5.8   3.2 | -20.2  -4.4  335  18  9   6.9   3.8
 26000 -18.6  -1.5  335  21 11   5.8   3.2 | -18.1  -0.6  335  18  9   6.9   3.8
 25000 -16.9   1.6  335  19 10   5.6   3.1 | -16.1   3.0  335  17  9   5.6   3.1
 24000 -15.3   4.5  335  17  9   5.5   3.0 | -14.6   5.7  330  16  8   5.0   2.7
 23000 -13.7   7.3  330  14  7   5.7   3.1 | -13.2   8.2  320  15  8   5.1   2.8
 22000 -12.1  10.2  325  12  6   6.6   3.6 | -11.7  10.9  315  15  8   6.3   3.5
 21000 -10.1  13.8  320  12  6   7.1   3.9 |  -9.7  14.5  305  14  7   6.9   3.8
 20000  -8.1  17.4  315  12  6   7.2   3.9 |  -7.8  18.0  300  13  7   7.0   3.9
 19500  -7.1  19.2  310  13  6   7.4   4.0 |  -6.8  19.8  295  13  7   7.4   4.1
 19000  -5.9  21.4  305  13  7   8.4   4.6 |  -5.6  21.9  295  13  7   9.1   5.0
 18500  -4.8  23.4  300  13  7   8.3   4.6 |  -4.4  24.1  295  13  7   9.1   5.0
 18000  -3.6  25.5  295  13  7   7.7   4.2 |  -3.1  26.4  295  13  7   7.7   4.2
 17500  -2.5  27.5  295  13  7   7.5   4.1 |  -2.1  28.2  300  13  7   7.3   4.0
 17000  -1.4  29.5  290  13  7   7.5   4.1 |  -1.0  30.2  300  14  7   7.2   4.0
 16500  -0.3  31.5  290  13  7   7.5   4.1 |   0.1  32.2  300  14  7   7.2   3.9
 16000   0.8  33.4  290  13  7   7.4   4.1 |   1.2  34.2  295  14  7   7.1   3.9
 15500   2.0  35.6  295  12  6   9.1   5.0 |   2.4  36.3  295  13  7   9.1   5.0
 15000   3.4  38.1  290  12  6   9.3   5.1 |   3.7  38.7  290  13  7   9.2   5.1
 14500   4.8  40.6  290  11  6   9.1   5.0 |   5.1  41.2  285  13  7   9.0   4.9
 14000   6.1  43.0  285  11  6   8.8   4.8 |   7.0  44.6  280  13  7   8.8   4.8
 13500   8.0  46.4  280  10  5   8.2   4.5 |   8.3  46.9  275  13  7   8.2   4.5
 13000   9.2  48.6  275  10  5   8.1   4.4 |   9.5  49.1  270  13  7   8.2   4.5
 12500  10.3  50.5  265   9  5   7.3   4.0 |  10.6  51.1  265  13  7   7.9   4.3
 12000  11.2  52.2  260   9  4   7.0   3.8 |  11.7  53.1  260  12  6   7.7   4.2
 11500  12.2  54.0  255   8  4   6.8   3.7 |  12.7  54.9  255  12  6   7.2   4.0
 11000  13.1  55.6  250   8  4   6.5   3.6 |  13.6  56.5  250  11  6   6.7   3.7
 10500  14.0  57.2  250   8  4   3.9   2.1 |  14.6  58.3  240  10  5   4.3   2.4
 10250  14.2  57.6  250   9  4   4.7   2.6 |  14.8  58.6  240   9  5   5.0   2.7
 10000  14.8  58.6  250   9  5   8.8   4.8 |  15.3  59.5  235   8  4   8.6   4.7
  9750  15.4  59.7  250  10  5   8.1   4.4 |  15.8  60.4  235   8  4   8.1   4.4
  9500  15.9  60.6  250  10  5   7.2   3.9 |  16.3  61.3  230   7  4   6.8   3.7
  9250  16.4  61.5  250  11  5   6.9   3.8 |  16.7  62.1  230   6  3   6.5   3.6
  9000  16.9  62.4  245  11  6   8.3   4.5 |  17.3  63.1  225   6  3   8.2   4.5
  8750  17.5  63.5  245  12  6   8.3   4.6 |  17.8  64.0  225   5  3   7.8   4.3
  8500  18.1  64.6  240  13  6   7.5   4.1 |  18.4  65.1  225   4  2   8.6   4.7
  8250  18.5  65.3  240  13  7   6.7   3.7 |  19.0  66.2  225   4  2   9.4   5.1
  8000  19.0  66.2  235  13  7   6.5   3.5 |  19.7  67.5  230   4  2   9.6   5.2
  7750  19.5  67.1  230  14  7   5.9   3.2 |  20.4  68.7  230   3  2   9.8   5.4
  7500  19.8  67.6  225  14  7   4.6   2.5 |  21.2  70.2  230   3  2  10.0   5.5
  7250  20.1  68.2  220  12  6   4.2   2.3 |  21.9  71.4  230   3  2  10.0   5.5
  7000  20.4  68.7  210  11  6   3.0   1.6 |  22.7  72.9  235   3  2  10.5   5.7
  6750  20.6  69.1  200  10  5   3.8   2.1 |  23.5  74.3  235   3  2  11.0   6.0
  6500  21.1  70.0  195   9  5   7.4   4.1 |  24.3  75.7  235   3  2  10.7   5.9
  6250  21.6  70.9  190   9  4   7.9   4.3 |  25.1  77.2  235   3  2  10.9   6.0
  6000  22.2  72.0  185   8  4   7.7   4.2 |  25.9  78.6  240   3  2   9.9   5.4
  5750  22.8  73.0  180   7  4   9.2   5.0 |  26.6  79.9  240   3  2  12.9   7.1
  5500  23.5  74.3  180   7  4  10.5   5.8 |  27.8  82.0  245   3  2  16.9   9.3
  5250  24.3  75.7  180   7  3   9.5   5.2 |  28.9  84.0  245   3  2  13.8   7.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/03/2015 at 1500 MDT          |       07/03/2015 at 1800 MDT
                                           |
K index... +29.1  LI... +269.0             | K index... +26.9  LI... +269.8
CAPE... +1219.7  CIN... -30.4              | CAPE... +871.4  CIN... -33.8
                                           |
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 -67.6 -89.7  310  26 13   0.3   0.2 | -67.6 -89.7  315  22 11   0.7   0.4
 45000 -63.0 -81.4  310  39 20   7.5   4.1 | -62.6 -80.7  305  33 17   7.4   4.0
 40000 -51.5 -60.7  295  43 22   8.6   4.7 | -51.3 -60.3  300  40 20   8.5   4.7
 38000 -46.3 -51.3  300  38 19   8.6   4.7 | -46.2 -51.2  300  35 18   8.5   4.7
 36000 -41.1 -42.0  305  33 17   8.3   4.5 | -41.0 -41.8  295  29 15   8.5   4.7
 34000 -36.3 -33.3  310  26 13   8.1   4.4 | -35.9 -32.6  300  25 13   8.5   4.7
 32000 -31.4 -24.5  325  19 10   8.3   4.5 | -30.8 -23.4  300  21 11   8.7   4.8
 30000 -26.1 -15.0  320  16  8   7.9   4.3 | -26.2 -15.2  305  18  9   7.7   4.2
 29000 -23.7 -10.7  320  15  8   7.9   4.3 | -23.3  -9.9  305  17  9   7.7   4.2
 28000 -21.5  -6.7  320  15  7   6.9   3.8 | -21.1  -6.0  310  16  8   6.5   3.6
 27000 -19.4  -2.9  320  15  8   6.9   3.8 | -19.1  -2.4  315  16  8   6.6   3.6
 26000 -17.3   0.9  325  16  8   6.9   3.8 | -17.2   1.0  320  16  8   6.6   3.6
 25000 -15.3   4.5  330  16  8   6.0   3.3 | -15.2   4.6  325  16  8   6.0   3.3
 24000 -13.6   7.5  325  16  8   5.6   3.1 | -13.5   7.7  325  16  8   5.7   3.1
 23000 -11.9  10.6  325  15  8   5.6   3.1 | -11.8  10.8  325  16  8   5.7   3.1
 22000 -10.2  13.6  325  15  8   6.2   3.4 | -10.1  13.8  325  16  8   6.3   3.5
 21000  -8.3  17.1  315  15  8   6.5   3.6 |  -8.2  17.2  325  16  8   6.7   3.7
 20000  -6.4  20.5  305  15  8   6.6   3.6 |  -6.2  20.8  325  17  9   6.8   3.7
 19500  -5.5  22.1  300  15  8   6.6   3.6 |  -5.2  22.6  325  17  9   6.8   3.8
 19000  -4.5  23.9  300  15  8   6.7   3.7 |  -4.3  24.3  325  17  9   6.9   3.8
 18500  -3.6  25.5  300  15  8   6.8   3.7 |  -3.3  26.1  325  16  8   7.1   3.9
 18000  -2.6  27.3  295  15  8   7.7   4.2 |  -2.4  27.7  320  15  8   7.6   4.2
 17500  -1.5  29.3  295  15  8   8.1   4.4 |  -1.3  29.7  325  14  7   7.8   4.3
 17000  -0.3  31.5  300  15  8   8.1   4.5 |  -0.2  31.6  325  13  7   7.8   4.3
 16500   0.8  33.4  300  14  7   7.7   4.2 |   1.0  33.8  325  12  6   8.2   4.5
 16000   1.8  35.2  300  14  7   7.8   4.3 |   2.2  36.0  320  11  6   8.2   4.5
 15500   3.0  37.4  300  13  7   8.5   4.6 |   3.4  38.1  320  10  5   8.4   4.6
 15000   4.2  39.6  295  13  7   8.6   4.7 |   4.6  40.3  315  10  5   8.5   4.7
 14500   6.1  43.0  295  13  7   9.0   4.9 |   5.8  42.4  310   9  5   8.7   4.7
 14000   7.4  45.3  290  12  6   9.0   4.9 |   7.7  45.9  310   9  5   8.9   4.9
 13500   8.7  47.7  285  12  6   8.8   4.8 |   9.0  48.2  305   9  5   8.9   4.9
 13000  10.0  50.0  285  12  6   8.8   4.8 |  10.3  50.5  305   8  4   8.9   4.9
 12500  11.3  52.3  280  12  6   8.7   4.8 |  11.6  52.9  300   8  4   8.9   4.9
 12000  12.5  54.5  275  11  6   8.6   4.7 |  13.0  55.4  300   8  4   8.9   4.9
 11500  13.7  56.7  275  11  6   7.9   4.4 |  14.3  57.7  295   8  4   8.4   4.6
 11000  14.7  58.5  270  10  5   7.3   4.0 |  15.5  59.9  290   7  4   7.8   4.3
 10500  15.7  60.3  265  10  5  10.9   6.0 |  16.5  61.7  285   6  3  11.2   6.2
 10250  16.7  62.1  265   9  5  11.6   6.4 |  17.6  63.7  280   6  3  11.4   6.3
 10000  17.2  63.0  265   8  4   7.1   3.9 |  18.1  64.6  275   5  3   6.8   3.7
  9750  17.8  64.0  265   7  4   8.7   4.8 |  18.7  65.7  265   5  2   8.1   4.5
  9500  18.4  65.1  265   6  3   6.8   3.7 |  19.2  66.6  250   4  2   7.5   4.1
  9250  18.8  65.8  265   5  3   6.7   3.7 |  19.7  67.5  235   4  2   7.7   4.2
  9000  19.3  66.7  265   5  2   8.4   4.6 |  20.2  68.4  220   4  2   8.1   4.5
  8750  19.9  67.8  265   4  2   7.6   4.2 |  20.8  69.4  210   5  2   7.8   4.3
  8500  20.4  68.7  265   3  2   9.3   5.1 |  21.3  70.3  200   5  3   8.9   4.9
  8250  21.2  70.2  260   3  2  10.8   5.9 |  21.9  71.4  195   5  3  10.0   5.5
  8000  21.9  71.4  260   3  2   9.8   5.4 |  22.6  72.7  195   6  3   9.4   5.2
  7750  22.6  72.7  260   3  2   9.6   5.2 |  23.3  73.9  195   6  3   8.8   4.8
  7500  23.3  73.9  260   3  1  10.2   5.6 |  23.9  75.0  195   6  3   9.9   5.4
  7250  24.1  75.4  260   3  1  11.0   6.0 |  24.7  76.5  195   6  3  11.2   6.2
  7000  24.9  76.8  260   3  1  10.1   5.6 |  25.5  77.9  195   6  3   9.9   5.4
  6750  25.7  78.3  260   3  2   9.7   5.3 |  26.2  79.2  195   6  3   8.8   4.8
  6500  26.4  79.5  260   3  2  10.5   5.8 |  26.9  80.4  195   6  3  10.5   5.7
  6250  27.2  81.0  260   3  2  11.1   6.1 |  27.7  81.9  195   6  3  11.7   6.4
  6000  28.0  82.4  255   3  1  10.1   5.5 |  28.5  83.3  195   6  3  10.6   5.8
  5750  28.8  83.8  260   3  1  12.6   6.9 |  29.3  84.7  195   6  3  10.1   5.5
  5500  29.9  85.8  260   3  2  16.8   9.2 |  30.1  86.2  195   6  3  11.3   6.2
  5250  31.1  88.0  260   3  2  15.5   8.5 |  30.9  87.6  195   6  3  12.0   6.6
  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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