Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 291641
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
1041 MDT Friday, August 29, 2014

This forecast is for Friday, August 29, 2014:

If the trigger temperature of 76.4 F/24.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1254 ft/min (6.4 m/s)
   Maximum height of thermals.................. 16587 ft MSL (11748 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 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................. 11472 ft MSL (6633 ft AGL)
Thermal soaring outlook for Saturday 08/30..... Good

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

Remarks...

Sunrise/Sunset.................... 06:40:08 / 19:50:32 MDT
Total possible sunshine........... 13 hr 10 min 25 sec (790 min 25 sec)
Altitude of sun at 13:14:55 MDT... 60.05 degrees

Upper air data from rawinsonde observation taken on 08/29/2014 at 0600 MDT

Freezing level.................. 14081 ft MSL (9242 ft AGL)
Convective condensation level... 12612 ft MSL (7773 ft AGL)
Lifted condensation level....... 13870 ft MSL (9031 ft AGL)
Lifted index.................... -2.2
K index......................... +26.9

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  -63.1 -81.6   300   26   13   5.2   2.9   90.8 195.4    35.4      M    M
 45000  -60.0 -76.0   290   46   24   5.3   2.9   70.2 158.4    25.3      M    M
 40000  -52.5 -62.5   290   48   25   2.6   1.4   59.1 138.4    19.7      M    M
 38000  -49.0 -56.2   285   47   24   6.4   3.5   55.8 132.4    18.0      M    M
 36000  -46.7 -52.1   290   44   23   4.6   2.5   50.6 123.1    14.8      M    M
 34000  -42.6 -44.7   290   43   22   8.0   4.4   47.9 118.3    13.3      M    M
 32000  -37.2 -35.0   290   43   22   7.9   4.4   46.4 115.5    12.5      M    M
 30000  -32.2 -26.0   285   43   22   8.5   4.6   45.4 113.8    12.1      M    M
 29000  -29.7 -21.5   285   40   21   6.6   3.6   44.8 112.6    11.8      M    M
 28000  -28.6 -19.5   285   37   19  -0.9  -0.5   42.4 108.3    10.0      M    M
 27000  -27.5 -17.5   285   35   18   7.1   3.9   40.2 104.3     8.3      M    M
 26000  -24.7 -12.5   285   32   16   9.6   5.3   40.1 104.1     8.3      M    M
 25000  -21.8  -7.2   285   29   15   9.6   5.3   40.1 104.1     8.4      M    M
 24000  -19.0  -2.2   285   27   14   9.5   5.2   39.9 103.8     8.4      M    M
 23000  -16.2   2.8   290   25   13   8.8   4.8   39.7 103.5     8.4      M    M
 22000  -13.5   7.7   290   23   12   8.8   4.8   39.3 102.8     8.2      M    M
 21000  -11.3  11.7   295   21   11   3.7   2.0   38.5 101.3     7.6      M    M
 20000  -10.1  13.8   300   19   10   4.6   2.5   36.5  97.7     6.0      M    M
 19500   -9.0  15.8   300   18    9   8.5   4.7   36.0  96.8     5.6      M    M
 19000   -7.8  18.0   295   17    9   8.1   4.4   35.7  96.3     5.4      M    M
 18500   -6.6  20.1   300   15    8   8.0   4.4   35.4  95.7     5.1      M    M
 18000   -5.4  22.3   305   14    7   8.1   4.4   35.1  95.2     4.9      M    M
 17500   -3.6  25.5   310   12    6   5.3   2.9   34.7  94.5     4.6      M    M
 17000   -2.9  26.8   315   11    6 -12.3  -6.7   33.8  92.9     3.8      M    M
 16500   -6.8  19.8   325   11    5  -1.1  -0.6   28.3  83.0    -1.6   1080  5.5
 16000   -5.4  22.3   330   10    5   9.0   4.9   28.3  83.0    -1.6   1022  5.2
 15500   -3.9  25.0   335   10    5   9.7   5.3   28.3  83.0    -1.6    963  4.9
 15000   -2.5  27.5   335   10    5   9.8   5.4   28.3  83.0    -1.7    905  4.6
 14500   -1.0  30.2   340   10    5   9.6   5.3   28.3  83.0    -1.7    846  4.3
 14000    0.4  32.7   340   10    5   7.4   4.1   28.4  83.0    -1.7    789  4.0
 13500    0.9  33.6   340    9    5   6.9   3.8   27.6  81.7    -2.6    758  3.8
 13000    2.2  36.0   345    9    5   9.2   5.1   27.4  81.4    -2.8    704  3.6
 12500    3.6  38.5   345    8    4   9.2   5.1   27.3  81.2    -2.8    647  3.3
 12000    5.1  41.2   350    8    4   9.2   5.1   27.3  81.1    -2.9    590  3.0
 11500    6.4  43.5   345    8    4   9.4   5.2   27.2  81.0    -3.0    534  2.7
 11000    7.8  46.0   340    9    4   9.4   5.2   27.2  80.9    -3.1    478  2.4
 10500    9.1  48.4   335    9    5   8.7   4.8   27.1  80.8    -3.2    424  2.2
 10250    9.7  49.5   335    9    4   7.8   4.3   27.0  80.5    -3.4    399  2.0
 10000   10.2  50.4   330    8    4   7.6   4.2   26.8  80.2    -3.6    376  1.9
  9750   10.7  51.3   325    7    4   7.7   4.2   26.6  79.9    -3.8    353  1.8
  9500   11.3  52.3   315    7    3   7.7   4.2   26.5  79.6    -4.1    330  1.7
  9250   11.8  53.2   310    6    3   7.6   4.2   26.3  79.4    -4.3    307  1.6
  9000   12.3  54.1   300    6    3   7.4   4.1   26.1  79.1    -4.5    283  1.4
  8750   12.9  55.2   290    4    2   7.4   4.0   26.0  78.7    -4.6    259  1.3
  8500   13.5  56.3   265    3    1   7.3   4.0   25.8  78.4    -4.8    234  1.2
  8250   14.0  57.2   215    2    1   7.7   4.2   25.6  78.0    -5.0    210  1.1
  8000   14.6  58.3   185    4    2   6.2   3.4   25.4  77.7    -5.1    186  0.9
  7750   14.9  58.8   165    5    3   3.4   1.9   25.0  77.0    -5.6    169  0.9
  7500   15.1  59.2   160    7    4   3.3   1.8   24.5  76.1    -6.1    155  0.8
  7250   15.3  59.5   155    9    5   2.1   1.1   24.0  75.2    -6.7    142  0.7
  7000   15.3  59.5   150   12    6  -0.6  -0.3   23.3  73.9    -7.4    135  0.7
  6750   15.2  59.4   150   11    6  -2.0  -1.1   22.4  72.4    -8.3    131  0.7
  6500   15.1  59.2   145   10    5   0.9   0.5   21.6  70.9    -9.2    128  0.6
  6250   15.3  59.5   140    9    4   5.9   3.2   21.1  70.1    -9.6    113  0.6
  6000   15.8  60.4   135    7    4   8.0   4.4   20.9  69.7    -9.9     90  0.5
  5750   16.4  61.5   130    7    4   4.7   2.6   20.8  69.4   -10.1     66  0.3
  5500   16.4  61.5   130    7    4  -2.1  -1.1   20.1  68.2   -10.8     58  0.3
  5250   16.1  61.0   125    7    4  -4.9  -2.7   19.1  66.3   -11.9     61  0.3
  5000   15.7  60.3   120    7    4  -1.8  -1.0   18.0  64.5   -13.0     64  0.3

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

           08/29/2014 at 0900 MDT          |       08/29/2014 at 1200 MDT
                                           |
K index... +30.6  LI... -1.9               | K index... +27.9  LI... -2.6
CAPE... +356.7  CIN... -30.5               | CAPE... +426.3  CIN... -29.9
                                           |
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 -63.1 -81.6  295  28 15   2.5   1.3 | -62.7 -80.9  285  32 16   2.6   1.4
 45000 -58.6 -73.5  295  42 21   4.6   2.5 | -58.3 -72.9  295  46 24   3.9   2.1
 40000 -51.4 -60.5  295  49 25   4.2   2.3 | -52.1 -61.8  295  50 26   4.4   2.4
 38000 -48.9 -56.0  300  46 24   4.2   2.3 | -49.5 -57.1  295  48 25   4.4   2.4
 36000 -46.4 -51.5  305  43 22   4.3   2.3 | -46.9 -52.4  295  46 24   4.4   2.4
 34000 -42.0 -43.6  305  43 22   8.2   4.5 | -42.4 -44.3  295  44 23   8.4   4.6
 32000 -37.1 -34.8  305  44 23   8.2   4.5 | -37.4 -35.3  300  42 22   8.4   4.6
 30000 -32.6 -26.7  305  40 21   7.2   4.0 | -32.7 -26.9  300  38 19   7.5   4.1
 29000 -30.4 -22.7  305  37 19   7.2   4.0 | -29.9 -21.8  305  34 17   7.5   4.1
 28000 -27.7 -17.9  305  33 17   6.6   3.6 | -27.7 -17.9  305  31 16   6.7   3.7
 27000 -25.9 -14.6  300  30 16   5.9   3.2 | -25.9 -14.6  305  28 14   6.0   3.3
 26000 -24.2 -11.6  300  27 14   5.9   3.2 | -24.1 -11.4  310  25 13   6.0   3.3
 25000 -22.4  -8.3  300  24 12   5.7   3.1 | -22.3  -8.1  310  22 11   5.9   3.3
 24000 -20.2  -4.4  305  23 12   8.0   4.4 | -20.2  -4.4  310  20 11   7.5   4.1
 23000 -17.8  -0.0  305  21 11   8.0   4.4 | -17.9  -0.2  315  19 10   7.5   4.1
 22000 -15.4   4.3  305  20 11   7.9   4.4 | -15.7   3.7  320  18  9   7.4   4.0
 21000 -13.3   8.1  310  19 10   6.8   3.7 | -13.6   7.5  325  17  9   6.7   3.7
 20000 -11.3  11.7  320  17  9   6.8   3.7 | -11.6  11.1  330  15  8   6.7   3.7
 19500 -10.2  13.6  320  16  8   7.0   3.8 | -10.6  12.9  330  14  7   6.8   3.7
 19000  -9.4  15.1  325  15  8   4.3   2.4 |  -9.7  14.5  335  13  7   5.9   3.3
 18500  -8.8  16.2  330  14  7   4.0   2.2 |  -8.8  16.2  345  12  6   5.9   3.3
 18000  -8.3  17.1  340  13  6   4.3   2.4 |  -8.0  17.6  350  12  6   6.2   3.4
 17500  -7.5  18.5  345  12  6   5.7   3.1 |  -7.0  19.4  355  11  6   7.0   3.8
 17000  -6.8  19.8  345  12  6   5.5   3.0 |  -6.0  21.2  360  11  6   7.1   3.9
 16500  -5.9  21.4  350  12  6   7.7   4.2 |  -5.1  22.8  005  11  5   6.5   3.6
 16000  -4.8  23.4  350  11  6   7.9   4.3 |  -4.2  24.4  005  11  5   6.6   3.6
 15500  -3.7  25.3  350  10  5   8.1   4.4 |  -3.2  26.2  005  10  5   7.4   4.1
 15000  -2.6  27.3  350   9  5   8.1   4.5 |  -2.1  28.2  360   9  5   8.0   4.4
 14500  -1.5  29.3  350   9  4   8.1   4.5 |  -1.0  30.2  355   9  4   8.1   4.5
 14000  -0.4  31.3  350   8  4   7.7   4.2 |   0.7  33.3  350   7  3   8.3   4.6
 13500   1.3  34.3  345   6  3   8.3   4.6 |   1.9  35.4  340   6  3   8.3   4.5
 13000   2.6  36.7  340   6  3   8.7   4.8 |   3.1  37.6  340   5  2   8.2   4.5
 12500   3.9  39.0  330   5  3   8.6   4.7 |   4.3  39.7  330   4  2   8.3   4.6
 12000   5.1  41.2  325   4  2   8.4   4.6 |   5.5  41.9  325   4  2   8.5   4.6
 11500   6.3  43.3  320   4  2   8.2   4.5 |   6.8  44.2  320   3  2   8.5   4.7
 11000   7.5  45.5  315   3  2   7.6   4.2 |   8.0  46.4  320   3  2   8.2   4.5
 10500   8.6  47.5  305   3  1   3.7   2.0 |   9.3  48.7  320   3  2   3.4   1.9
 10250   8.8  47.8  305   2  1   5.1   2.8 |   9.4  48.9  320   3  2   4.4   2.4
 10000   9.5  49.1  300   2  1  11.3   6.2 |  10.1  50.2  320   3  1  11.6   6.4
  9750  10.2  50.4  295   1  1  10.2   5.6 |  10.8  51.4  320   3  1  10.4   5.7
  9500  10.9  51.6  280   1  1   8.4   4.6 |  11.6  52.9  320   2  1   8.2   4.5
  9250  11.4  52.5  270   1  0   6.2   3.4 |  12.0  53.6  315   2  1   6.5   3.6
  9000  11.9  53.4  000   0  0   8.0   4.4 |  12.6  54.7  310   2  1   9.1   5.0
  8750  12.5  54.5  180   1  0   8.7   4.8 |  13.3  55.9  300   2  1   9.5   5.2
  8500  13.1  55.6  155   1  0   7.7   4.2 |  13.9  57.0  285   1  1   8.3   4.5
  8250  13.6  56.5  160   1  1   7.2   3.9 |  14.5  58.1  260   1  1   7.6   4.2
  8000  14.1  57.4  160   2  1   7.0   3.8 |  15.0  59.0  235   1  1   7.3   4.0
  7750  14.6  58.3  165   2  1   6.1   3.4 |  15.5  59.9  210   1  1   7.2   3.9
  7500  15.0  59.0  170   3  2   4.8   2.6 |  16.1  61.0  200   2  1   8.3   4.5
  7250  15.3  59.5  170   4  2   3.8   2.1 |  16.7  62.1  195   2  1   8.5   4.7
  7000  15.7  60.3  170   5  3   4.7   2.6 |  17.3  63.1  195   2  1   8.8   4.8
  6750  16.0  60.8  170   6  3   2.5   1.4 |  18.0  64.4  195   2  1  10.3   5.7
  6500  16.1  61.0  165   6  3  -0.7  -0.4 |  18.8  65.8  195   2  1  11.0   6.0
  6250  16.0  60.8  160   6  3  -0.0  -0.0 |  19.6  67.3  195   2  1  11.2   6.2
  6000  16.0  60.8  155   5  3  -2.4  -1.3 |  20.4  68.7  200   2  1   9.8   5.4
  5750  15.8  60.4  150   4  2   2.9   1.6 |  21.1  70.0  200   2  1  11.4   6.3
  5500  16.4  61.5  145   4  2  10.6   5.8 |  22.1  71.8  205   2  1  14.6   8.0
  5250  17.0  62.6  145   3  2   4.6   2.5 |  23.1  73.6  205   2  1  12.1   6.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/29/2014 at 1500 MDT          |       08/29/2014 at 1800 MDT
                                           |
K index... +14.7  LI... -2.7               | K index... +16.9  LI... -1.5
CAPE... +449.3  CIN... -23.6               | CAPE... +183.7  CIN... -57.9
                                           |
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 -62.9 -81.2  290  37 19   2.5   1.4 | -62.7 -80.9  290  39 20   2.7   1.5
 45000 -58.5 -73.3  295  50 26   4.2   2.3 | -58.6 -73.5  300  49 25   3.1   1.7
 40000 -52.0 -61.6  295  49 25   3.8   2.1 | -53.6 -64.5  305  48 25   4.8   2.6
 38000 -49.7 -57.5  295  49 25   3.8   2.1 | -50.8 -59.4  310  55 28   4.7   2.6
 36000 -47.4 -53.3  300  49 25   3.9   2.2 | -47.9 -54.2  310  61 32   4.8   2.6
 34000 -43.1 -45.6  300  49 25   8.2   4.5 | -43.3 -45.9  310  60 31   8.7   4.7
 32000 -38.2 -36.8  300  48 25   8.2   4.5 | -38.1 -36.6  310  56 29   8.7   4.8
 30000 -33.4 -28.1  300  42 22   8.0   4.4 | -33.3 -27.9  315  48 25   7.8   4.3
 29000 -30.4 -22.7  305  37 19   8.0   4.4 | -31.0 -23.8  315  44 22   7.8   4.3
 28000 -28.1 -18.6  305  33 17   7.1   3.9 | -28.0 -18.4  315  38 20   7.3   4.0
 27000 -26.1 -15.0  305  29 15   6.4   3.5 | -26.0 -14.8  315  32 17   6.9   3.8
 26000 -24.2 -11.6  305  24 13   6.4   3.5 | -23.9 -11.0  310  26 14   7.0   3.8
 25000 -22.3  -8.1  310  20 10   6.4   3.5 | -21.8  -7.2  310  21 11   7.0   3.8
 24000 -20.1  -4.2  310  17  9   7.4   4.1 | -19.7  -3.5  310  17  9   7.1   3.9
 23000 -17.9  -0.2  315  15  8   7.5   4.1 | -17.6   0.3  310  13  7   7.1   3.9
 22000 -15.6   3.9  320  13  7   7.3   4.0 | -15.4   4.3  315  10  5   7.0   3.9
 21000 -13.6   7.5  330  11  6   6.7   3.7 | -13.4   7.9  325   8  4   6.7   3.7
 20000 -11.6  11.1  335  10  5   6.8   3.7 | -11.4  11.5  335   6  3   6.8   3.7
 19500 -10.6  12.9  340  10  5   6.7   3.7 | -10.4  13.3  345   5  3   6.7   3.7
 19000  -9.5  14.9  345   9  5   8.0   4.4 |  -9.4  15.1  355   5  3   7.9   4.3
 18500  -8.4  16.9  345   9  5   8.0   4.4 |  -8.2  17.2  355   5  3   7.9   4.4
 18000  -7.2  19.0  345   9  4   8.0   4.4 |  -7.1  19.2  360   5  3   7.9   4.3
 17500  -6.0  21.2  350   8  4   7.9   4.3 |  -5.9  21.4  360   5  3   7.7   4.3
 17000  -4.8  23.4  355   8  4   8.0   4.4 |  -4.8  23.4  005   5  3   7.7   4.2
 16500  -3.7  25.3  360   7  4   7.1   3.9 |  -3.6  25.5  010   5  3   8.0   4.4
 16000  -2.6  27.3  010   8  4   7.2   3.9 |  -2.5  27.5  015   5  3   8.1   4.4
 15500  -1.6  29.1  015   8  4   7.3   4.0 |  -1.3  29.7  020   5  3   8.1   4.5
 15000  -0.5  31.1  020   8  4   7.5   4.1 |  -0.1  31.8  020   5  3   8.2   4.5
 14500   0.6  33.1  025   8  4   7.7   4.2 |   1.1  34.0  020   5  3   8.3   4.6
 14000   2.3  36.1  025   8  4   8.1   4.5 |   2.3  36.1  020   5  3   8.6   4.7
 13500   3.5  38.3  025   7  4   8.2   4.5 |   4.2  39.6  015   5  3   8.7   4.8
 13000   4.7  40.5  025   6  3   8.3   4.6 |   5.4  41.7  015   5  3   8.7   4.8
 12500   5.9  42.6  020   5  3   8.4   4.6 |   6.7  44.1  010   5  3   8.7   4.8
 12000   7.1  44.8  015   4  2   8.4   4.6 |   8.0  46.4  010   5  3   8.7   4.8
 11500   8.3  46.9  360   3  1   8.5   4.7 |   9.3  48.7  010   5  2   8.6   4.7
 11000   9.5  49.1  340   2  1   8.4   4.6 |  10.5  50.9  010   4  2   8.3   4.5
 10500  10.7  51.3  310   2  1   5.5   3.0 |  11.8  53.2  010   4  2   4.9   2.7
 10250  11.0  51.8  305   2  1   6.5   3.6 |  12.1  53.8  010   4  2   5.9   3.2
 10000  11.7  53.1  295   2  1  10.9   6.0 |  12.8  55.0  010   4  2  11.0   6.1
  9750  12.4  54.3  290   2  1  10.4   5.7 |  13.6  56.5  010   4  2  10.1   5.5
  9500  13.1  55.6  280   3  1   8.3   4.6 |  14.3  57.7  010   4  2   8.8   4.8
  9250  13.6  56.5  280   3  1   6.9   3.8 |  14.9  58.8  010   3  2   7.6   4.2
  9000  14.2  57.6  275   3  2   9.0   4.9 |  15.5  59.9  010   3  1   8.8   4.8
  8750  14.9  58.8  275   3  2   9.1   5.0 |  16.2  61.2  005   2  1   8.9   4.9
  8500  15.5  59.9  275   3  2   8.5   4.6 |  16.8  62.2  360   2  1   8.4   4.6
  8250  16.0  60.8  275   3  2   7.8   4.3 |  17.4  63.3  350   2  1   7.9   4.3
  8000  16.6  61.9  275   3  2   8.6   4.7 |  18.0  64.4  335   2  1   7.9   4.3
  7750  17.2  63.0  270   3  2   9.2   5.1 |  18.5  65.3  325   2  1   7.7   4.2
  7500  17.9  64.2  270   3  2   9.7   5.3 |  19.1  66.4  315   2  1   8.2   4.5
  7250  18.6  65.5  270   3  2   9.9   5.5 |  19.6  67.3  305   2  1   8.6   4.7
  7000  19.3  66.7  270   3  2   9.9   5.4 |  20.1  68.2  300   2  1   8.6   4.7
  6750  20.1  68.2  270   3  2  10.5   5.8 |  20.7  69.3  300   2  1   9.3   5.1
  6500  20.9  69.6  265   3  2  10.9   6.0 |  21.4  70.5  295   2  1  10.2   5.6
  6250  21.7  71.1  265   3  2  11.3   6.2 |  22.2  72.0  290   2  1  10.8   6.0
  6000  22.5  72.5  265   3  2  10.0   5.5 |  23.0  73.4  285   2  1   9.5   5.2
  5750  23.2  73.8  265   3  2  11.7   6.4 |  23.6  74.5  280   2  1   8.6   4.7
  5500  24.2  75.6  270   3  2  14.8   8.1 |  24.3  75.7  285   2  1   9.5   5.2
  5250  25.2  77.4  270   3  2  12.4   6.8 |  24.9  76.8  285   2  1   8.7   4.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken at Walker Field in Grand
Junction, Colorado at

                   North Latitude:  39 deg 07 min 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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