Soaring Guidance
Issued by NWS Grand Junction, CO

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UXUS97 KGJT 281301
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0701 MDT Thursday, July 28, 2016

This forecast is for Thursday, July 28, 2016:

If the trigger temperature of 93.5 F/34.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1696 ft/min (8.6 m/s)
   Maximum height of thermals.................. 21913 ft MSL (17074 ft AGL)

Forecast maximum temperature................... 102.0 F/39.3 C
Time of trigger temperature.................... 1500 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................. 11437 ft MSL (6597 ft AGL)
Thermal soaring outlook for Friday 07/29....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:11:37 / 20:29:52 MDT
Total possible sunshine........... 14 hr 18 min 15 sec (858 min 15 sec)
Altitude of sun at 13:20:33 MDT... 69.60 degrees

Upper air data from rawinsonde observation taken on 07/28/2016 at 0600 MDT

Freezing level.................. 16920 ft MSL (12081 ft AGL)
Convective condensation level... 19426 ft MSL (14587 ft AGL)
Lifted condensation level....... 20591 ft MSL (15751 ft AGL)
Lifted index.................... -0.5
K index......................... +11.7

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  -66.9 -88.4   300   37   19   3.0   1.7   81.3 178.4    24.7      M    M
 45000  -58.3 -72.9   285   38   20   5.5   3.0   70.1 158.3    19.6      M    M
 40000  -49.4 -56.9   290   40   20   6.8   3.7   61.3 142.3    15.0      M    M
 38000  -46.4 -51.5   285   39   20   4.1   2.3   56.9 134.4    12.4      M    M
 36000  -43.7 -46.7   280   39   20   8.1   4.4   52.6 126.8     9.7      M    M
 34000  -38.9 -38.0   285   40   20   7.9   4.4   51.1 124.0     8.8      M    M
 32000  -34.1 -29.4   290   34   18   7.9   4.4   49.7 121.5     8.0      M    M
 30000  -28.9 -20.0   290   29   15   7.7   4.2   48.1 118.5     7.0      M    M
 29000  -26.6 -15.9   290   25   13   7.7   4.2   47.3 117.1     6.5      M    M
 28000  -24.3 -11.7   270   19   10   7.7   4.3   46.5 115.7     5.9      M    M
 27000  -22.0  -7.6   265   21   11   8.1   4.5   45.7 114.2     5.3      M    M
 26000  -20.4  -4.7   300   20   10   3.5   1.9   43.9 111.0     4.0      M    M
 25000  -18.0  -0.4   310   21   11   8.1   4.4   43.2 109.8     3.5      M    M
 24000  -15.8   3.6   325   24   12   7.6   4.2   42.5 108.5     2.9      M    M
 23000  -13.5   7.7   325   28   14   7.4   4.1   41.7 107.0     2.3      M    M
 22000  -11.7  10.9   320   31   16  -9.9  -5.5   40.3 104.5     1.1      M    M
 21000  -11.6  11.1   320   35   18   8.7   4.8   37.2  98.9    -1.7   1644  8.4
 20000   -9.1  15.6   300   27   14   8.7   4.8   36.8  98.2    -2.2   1540  7.8
 19500   -7.8  18.0   300   24   13   9.1   5.0   36.6  97.9    -2.4   1487  7.6
 19000   -6.4  20.5   295   22   11   9.7   5.3   36.6  97.8    -2.4   1430  7.3
 18500   -5.0  23.0   290   20   10   9.7   5.3   36.5  97.8    -2.5   1372  7.0
 18000   -3.5  25.7   285   18    9   9.7   5.3   36.5  97.8    -2.5   1314  6.7
 17500   -2.1  28.2   290   18    9   9.8   5.4   36.5  97.8    -2.5   1255  6.4
 17000   -0.6  30.9   295   18    9   9.8   5.4   36.5  97.8    -2.5   1196  6.1
 16500    1.6  34.9   300   19   10   9.9   5.4   36.6  97.9    -2.5   1108  5.6
 16000    3.1  37.6   305   19   10   9.9   5.4   36.6  97.9    -2.5   1049  5.3
 15500    4.5  40.1   300   19   10   9.4   5.2   36.6  97.9    -2.5    991  5.0
 15000    5.9  42.6   300   19   10   9.5   5.2   36.6  97.8    -2.6    934  4.7
 14500    7.3  45.1   295   19   10   9.5   5.2   36.6  97.8    -2.6    877  4.5
 14000    8.8  47.8   295   19   10   9.5   5.2   36.5  97.8    -2.6    819  4.2
 13500   10.2  50.4   300   20   10   9.5   5.2   36.5  97.6    -2.7    762  3.9
 13000   11.6  52.9   305   20   10   9.5   5.2   36.4  97.5    -2.8    705  3.6
 12500   13.0  55.4   310   21   11   9.5   5.2   36.4  97.5    -2.8    648  3.3
 12000   14.4  57.9   315   22   11   9.4   5.2   36.4  97.4    -2.9    591  3.0
 11500   15.8  60.4   325   18    9   8.5   4.6   36.3  97.3    -3.0    534  2.7
 11000   16.9  62.4   335   14    7   7.6   4.2   35.9  96.7    -3.3    486  2.5
 10500   18.1  64.6   335   12    6   8.0   4.4   35.6  96.0    -3.7    437  2.2
 10250   18.7  65.7   335   10    5   8.4   4.6   35.5  95.8    -3.8    412  2.1
 10000   19.3  66.7   335    8    4   8.3   4.6   35.4  95.6    -4.0    386  2.0
  9750   19.9  67.8   340    6    3   8.4   4.6   35.2  95.4    -4.1    360  1.8
  9500   20.5  68.9   340    5    2   8.4   4.6   35.1  95.3    -4.2    335  1.7
  9250   21.1  70.0   345    3    1   8.4   4.6   35.1  95.1    -4.3    309  1.6
  9000   21.7  71.1   005    1    1   8.4   4.6   35.0  94.9    -4.4    284  1.4
  8750   22.3  72.1   090    1    1   8.4   4.6   34.8  94.7    -4.6    258  1.3
  8500   22.9  73.2   115    3    1   8.4   4.6   34.7  94.5    -4.7    232  1.2
  8250   23.5  74.3   120    4    2   8.4   4.6   34.6  94.3    -4.8    207  1.0
  8000   24.1  75.4   125    6    3   8.4   4.6   34.5  94.2    -5.0    181  0.9
  7750   24.8  76.6   125    6    3   8.5   4.7   34.4  94.0    -5.1    155  0.8
  7500   25.4  77.7   125    5    3   8.1   4.4   34.3  93.8    -5.3    130  0.7
  7250   25.8  78.4   130    5    2   3.4   1.9   34.0  93.3    -5.5    109  0.6
  7000   25.9  78.6   130    4    2   0.7   0.4   33.4  92.1    -6.2    100  0.5
  6750   25.9  78.6   130    6    3   0.9   0.5   32.7  90.9    -6.9     91  0.5
  6500   26.0  78.8   135    9    5   3.0   1.6   32.1  89.7    -7.6     83  0.4
  6250   26.0  78.8   135   12    6  -5.9  -3.3   31.4  88.6    -8.3     74  0.4
  6000   25.2  77.4   135   14    7  -7.4  -4.0   29.9  85.8    -9.9     90  0.5
  5750   25.3  77.5   135   14    7   4.0   2.2   29.2  84.5   -10.6     81  0.4
  5500   25.6  78.1   130   12    6   3.8   2.1   28.7  83.7   -11.0     63  0.3
  5250   25.3  77.5   130   10    5 -20.5 -11.3   27.7  81.8   -12.1     66  0.3
  5000   22.3  72.1   125    9    5 -53.2 -29.2   24.0  75.2   -15.8    147  0.7

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

           07/28/2016 at 0900 MDT          |       07/28/2016 at 1200 MDT
                                           |
K index... +9.3  LI... +273.7              | K index... +11.6  LI... +273.7
CAPE... 0.0  CIN... -0.3                   | CAPE... +20.0  CIN... -88.7
                                           |
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 -64.0 -83.2  295  23 12   1.6   0.9 | -63.7 -82.7  295  25 13   1.4   0.8
 45000 -59.3 -74.7  295  39 20   6.0   3.3 | -59.4 -74.9  295  42 21   5.7   3.1
 40000 -49.9 -57.8  295  43 22   6.2   3.4 | -50.2 -58.4  295  46 24   6.2   3.4
 38000 -46.1 -51.0  295  44 23   6.2   3.4 | -46.5 -51.7  295  43 22   6.2   3.4
 36000 -42.4 -44.3  295  45 23   6.5   3.6 | -42.8 -45.0  295  40 20   6.6   3.6
 34000 -38.4 -37.1  290  41 21   6.7   3.7 | -38.6 -37.5  295  38 19   7.0   3.8
 32000 -34.4 -29.9  285  38 20   6.9   3.8 | -34.4 -29.9  295  36 18   7.2   3.9
 30000 -30.1 -22.2  285  35 18   7.2   3.9 | -30.1 -22.2  290  35 18   7.1   3.9
 29000 -28.0 -18.4  280  33 17   7.2   3.9 | -28.0 -18.4  290  35 18   7.1   3.9
 28000 -25.8 -14.4  280  31 16   6.9   3.8 | -25.9 -14.6  285  34 18   6.9   3.8
 27000 -23.3  -9.9  285  28 14   6.9   3.8 | -23.3  -9.9  285  32 16   6.9   3.8
 26000 -21.2  -6.2  285  25 13   6.9   3.8 | -21.2  -6.2  285  30 15   6.9   3.8
 25000 -19.2  -2.6  290  23 12   6.6   3.6 | -19.2  -2.6  285  28 15   6.0   3.3
 24000 -17.3   0.9  300  24 12   6.6   3.6 | -17.5   0.5  295  29 15   5.9   3.3
 23000 -15.3   4.5  305  25 13   6.7   3.7 | -15.8   3.6  305  32 16   6.0   3.3
 22000 -13.3   8.1  315  27 14   7.9   4.4 | -13.9   7.0  315  34 17   9.0   4.9
 21000 -11.0  12.2  315  26 13   8.0   4.4 | -11.3  11.7  310  31 16   8.9   4.9
 20000  -8.7  16.3  315  25 13   8.1   4.4 |  -8.7  16.3  310  28 14   9.0   4.9
 19500  -7.5  18.5  315  25 13   8.9   4.9 |  -7.4  18.7  310  26 14   9.2   5.1
 19000  -6.1  21.0  315  23 12   9.6   5.3 |  -6.0  21.2  310  24 13   9.4   5.1
 18500  -4.6  23.7  315  22 11   9.7   5.3 |  -4.6  23.7  305  22 11   9.4   5.2
 18000  -3.2  26.2  315  21 11   9.5   5.2 |  -3.2  26.2  305  21 11   9.4   5.2
 17500  -1.7  28.9  315  21 11   9.5   5.2 |  -1.8  28.8  300  19 10   9.4   5.2
 17000  -0.3  31.5  315  21 11   9.5   5.2 |  -0.4  31.3  300  18  9   9.4   5.1
 16500   1.1  34.0  315  20 10   9.4   5.2 |   1.0  33.8  300  18  9   9.3   5.1
 16000   2.5  36.5  315  20 10   9.4   5.2 |   2.4  36.3  300  18  9   9.3   5.1
 15500   3.9  39.0  315  19 10   8.9   4.9 |   3.8  38.8  300  17  9   9.2   5.0
 15000   5.2  41.4  310  19 10   9.0   4.9 |   5.2  41.4  305  17  9   9.2   5.0
 14500   6.6  43.9  310  19 10   9.1   5.0 |   6.6  43.9  305  17  9   9.4   5.1
 14000   7.9  46.2  310  18  9   9.2   5.0 |   8.0  46.4  305  17  9   9.4   5.1
 13500   9.3  48.7  310  18  9   9.1   5.0 |   9.4  48.9  310  17  9   9.1   5.0
 13000  11.3  52.3  310  18  9   9.0   5.0 |  11.4  52.5  310  17  9   8.7   4.8
 12500  12.7  54.9  310  18  9   8.9   4.9 |  12.7  54.9  310  16  8   9.4   5.1
 12000  14.0  57.2  310  17  9   8.9   4.9 |  14.1  57.4  315  16  8   9.4   5.2
 11500  15.3  59.5  310  17  9   8.8   4.8 |  15.5  59.9  315  16  8   9.0   4.9
 11000  16.6  61.9  310  17  9   9.3   5.1 |  16.8  62.2  315  15  8   9.6   5.3
 10500  17.6  63.7  310  16  8   4.7   2.6 |  17.8  64.0  315  14  7   5.3   2.9
 10250  18.1  64.6  310  16  8   8.8   4.8 |  18.4  65.1  310  14  7  10.2   5.6
 10000  18.9  66.0  310  16  8  10.9   6.0 |  19.2  66.6  310  13  7  11.0   6.0
  9750  19.7  67.5  310  15  8  10.0   5.5 |  20.0  68.0  310  12  6  10.3   5.6
  9500  20.4  68.7  305  15  8   7.2   3.9 |  20.7  69.3  310  12  6   7.1   3.9
  9250  20.8  69.4  305  14  7   6.4   3.5 |  21.1  70.0  305  11  6   6.6   3.6
  9000  21.4  70.5  300  13  7   7.8   4.3 |  21.7  71.1  300  10  5   8.2   4.5
  8750  22.0  71.6  300  12  6   7.2   3.9 |  22.2  72.0  290   9  5   7.4   4.1
  8500  22.4  72.3  295  11  6   6.0   3.3 |  22.8  73.0  285   8  4   6.4   3.5
  8250  22.8  73.0  290   9  5   5.3   2.9 |  23.2  73.8  280   7  4   6.0   3.3
  8000  23.1  73.6  280   7  4   4.0   2.2 |  23.6  74.5  270   6  3   5.5   3.0
  7750  23.3  73.9  270   6  3   3.0   1.6 |  24.0  75.2  260   6  3   6.7   3.7
  7500  23.4  74.1  250   4  2   3.2   1.8 |  24.6  76.3  255   5  3   9.1   5.0
  7250  23.6  74.5  220   4  2   3.0   1.6 |  25.2  77.4  255   5  3   9.6   5.3
  7000  23.8  74.8  195   4  2   3.6   2.0 |  25.9  78.6  250   5  3   9.2   5.0
  6750  24.1  75.4  180   5  3   1.1   0.6 |  26.5  79.7  250   5  3  10.3   5.6
  6500  24.0  75.2  170   5  3  -1.6  -0.9 |  27.4  81.3  250   5  3  11.4   6.2
  6250  23.9  75.0  160   5  3  -0.7  -0.4 |  28.2  82.8  250   5  3  11.5   6.3
  6000  23.8  74.8  150   5  3  -2.0  -1.1 |  29.0  84.2  250   5  2  10.2   5.6
  5750  23.7  74.7  135   5  2   3.9   2.1 |  29.8  85.6  250   5  2  12.3   6.7
  5500  24.3  75.7  135   4  2  10.5   5.8 |  30.9  87.6  250   5  2  15.8   8.7
  5250  24.9  76.8  130   4  2   5.4   3.0 |  31.9  89.4  250   5  2  13.1   7.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/28/2016 at 1500 MDT          |       07/28/2016 at 1800 MDT
                                           |
K index... +12.6  LI... +273.9             | K index... +16.1  LI... +273.6
CAPE... +19.5  CIN... -68.1                | CAPE... 0.0  CIN... -10.2
                                           |
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 -63.4 -82.1  300  29 15   1.6   0.9 | -63.0 -81.4  305  30 15   1.3   0.7
 45000 -59.1 -74.4  300  44 23   5.2   2.8 | -59.3 -74.7  305  47 24   4.8   2.6
 40000 -50.6 -59.1  300  48 25   6.3   3.4 | -51.3 -60.3  305  50 26   6.4   3.5
 38000 -46.9 -52.4  300  43 22   6.2   3.4 | -47.5 -53.5  305  42 22   6.4   3.5
 36000 -43.1 -45.6  300  37 19   6.8   3.7 | -43.6 -46.5  310  33 17   7.1   3.9
 34000 -38.8 -37.8  300  33 17   7.3   4.0 | -39.1 -38.4  310  30 16   7.5   4.1
 32000 -34.4 -29.9  300  29 15   7.4   4.1 | -34.6 -30.3  315  27 14   7.7   4.2
 30000 -30.2 -22.4  305  27 14   7.1   3.9 | -30.3 -22.5  310  27 14   7.2   4.0
 29000 -28.1 -18.6  305  26 13   7.1   3.9 | -28.1 -18.6  310  27 14   7.2   4.0
 28000 -26.0 -14.8  305  25 13   6.2   3.4 | -26.0 -14.8  310  27 14   7.1   3.9
 27000 -23.7 -10.7  305  26 13   6.2   3.4 | -23.4 -10.1  310  28 14   7.1   3.9
 26000 -21.9  -7.4  305  26 13   6.3   3.4 | -21.3  -6.3  310  29 15   7.1   3.9
 25000 -19.9  -3.8  305  27 14   7.9   4.3 | -19.1  -2.4  310  30 15   7.8   4.3
 24000 -17.6   0.3  310  29 15   8.0   4.4 | -16.8   1.8  315  31 16   7.8   4.3
 23000 -15.2   4.6  315  32 16   8.0   4.4 | -14.5   5.9  315  31 16   7.8   4.3
 22000 -12.8   9.0  320  34 17   8.6   4.7 | -12.2  10.0  315  31 16   8.2   4.5
 21000 -10.3  13.5  320  33 17   8.6   4.7 |  -9.8  14.4  320  29 15   8.2   4.5
 20000  -7.8  18.0  320  31 16   8.6   4.7 |  -7.3  18.9  320  28 14   8.3   4.5
 19500  -6.6  20.1  320  31 16   8.9   4.9 |  -6.1  21.0  320  27 14   8.5   4.7
 19000  -5.2  22.6  320  29 15   9.1   5.0 |  -4.8  23.4  320  25 13   8.7   4.8
 18500  -3.9  25.0  315  26 14   9.2   5.1 |  -3.6  25.5  320  23 12   8.7   4.8
 18000  -2.5  27.5  315  24 13   8.6   4.7 |  -2.3  27.9  320  22 11   9.1   5.0
 17500  -1.3  29.7  315  22 11   8.6   4.7 |  -0.9  30.4  320  21 11   9.1   5.0
 17000   0.0  32.0  310  20 10   8.9   4.9 |   0.4  32.7  320  20 10   9.2   5.0
 16500   1.4  34.5  310  19 10   9.2   5.0 |   1.8  35.2  320  19 10   9.3   5.1
 16000   2.8  37.0  310  18  9   9.2   5.1 |   3.2  37.8  320  18  9   9.3   5.1
 15500   4.2  39.6  305  17  9   9.1   5.0 |   4.6  40.3  320  17  9   9.4   5.2
 15000   5.5  41.9  305  17  9   9.1   5.0 |   6.0  42.8  320  17  9   9.4   5.2
 14500   6.9  44.4  305  16  8   9.5   5.2 |   7.4  45.3  320  16  8   9.5   5.2
 14000   8.3  46.9  300  15  8   9.6   5.2 |   8.8  47.8  320  15  8   9.5   5.2
 13500   9.7  49.5  300  15  8   9.4   5.2 |  10.2  50.4  315  15  8   9.5   5.2
 13000  11.8  53.2  295  14  7   9.3   5.1 |  12.4  54.3  315  14  7   9.6   5.3
 12500  13.2  55.8  295  14  7   9.5   5.2 |  13.8  56.8  315  13  7   9.5   5.2
 12000  14.7  58.5  295  13  7   9.5   5.2 |  15.2  59.4  310  12  6   9.5   5.2
 11500  16.1  61.0  295  13  7   9.3   5.1 |  16.6  61.9  310  12  6   9.4   5.1
 11000  17.4  63.3  295  12  6  10.1   5.6 |  18.0  64.4  305  11  6  10.2   5.6
 10500  18.4  65.1  290  12  6   5.9   3.2 |  18.9  66.0  305  11  6   6.5   3.6
 10250  19.1  66.4  290  11  6  11.2   6.2 |  19.7  67.5  300  11  6  11.7   6.4
 10000  19.9  67.8  290  11  6  10.6   5.8 |  20.5  68.9  300  11  5  10.2   5.6
  9750  20.7  69.3  290  10  5  10.4   5.7 |  21.3  70.3  295  10  5  10.8   5.9
  9500  21.4  70.5  290  10  5   7.3   4.0 |  22.0  71.6  295  10  5   7.8   4.3
  9250  21.9  71.4  290  10  5   7.9   4.4 |  22.5  72.5  295  10  5   7.8   4.3
  9000  22.6  72.7  290   9  5  10.3   5.6 |  23.2  73.8  290  10  5  10.0   5.5
  8750  23.3  73.9  285   9  5   9.5   5.2 |  24.0  75.2  290  10  5   9.4   5.1
  8500  24.0  75.2  285   9  4   8.8   4.8 |  24.6  76.3  290   9  5   8.4   4.6
  8250  24.6  76.3  285   8  4   8.6   4.7 |  25.2  77.4  285   9  5   7.7   4.2
  8000  25.3  77.5  285   8  4   9.5   5.2 |  25.8  78.4  285   9  5   8.1   4.4
  7750  25.9  78.6  285   8  4   9.9   5.4 |  26.4  79.5  285   9  4   8.3   4.5
  7500  26.7  80.1  285   8  4  10.0   5.5 |  27.1  80.8  280   8  4   9.1   5.0
  7250  27.4  81.3  285   8  4  10.0   5.5 |  27.8  82.0  280   8  4   9.5   5.2
  7000  28.2  82.8  285   8  4  10.0   5.5 |  28.5  83.3  280   8  4   9.4   5.2
  6750  28.9  84.0  280   8  4  10.5   5.7 |  29.2  84.6  280   8  4  10.0   5.5
  6500  29.7  85.5  280   8  4  10.7   5.9 |  30.0  86.0  280   8  4  10.6   5.8
  6250  30.5  86.9  280   8  4  11.2   6.1 |  30.8  87.4  280   8  4  11.2   6.2
  6000  31.4  88.5  280   8  4   9.3   5.1 |  31.6  88.9  275   8  4   9.5   5.2
  5750  32.1  89.8  280   7  4  12.3   6.7 |  32.3  90.1  275   7  4   9.6   5.2
  5500  33.3  91.9  280   7  4  17.3   9.5 |  33.0  91.4  275   7  4  11.7   6.4
  5250  34.4  93.9  280   7  4  13.4   7.3 |  33.8  92.8  280   7  4  10.0   5.5
  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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