Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 231235
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0635 MDT Saturday, July 23, 2016

This forecast is for Saturday, July 23, 2016:

If the trigger temperature of 86.7 F/30.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1318 ft/min (6.7 m/s)
   Maximum height of thermals.................. 19140 ft MSL (14301 ft AGL)

Forecast maximum temperature................... 98.0 F/37.1 C
Time of trigger temperature.................... 1100 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................. 12271 ft MSL (7432 ft AGL)
Thermal soaring outlook for Sunday 07/24....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:07:22 / 20:34:07 MDT
Total possible sunshine........... 14 hr 26 min 45 sec (866 min 45 sec)
Altitude of sun at 13:20:35 MDT... 70.71 degrees

Upper air data from rawinsonde observation taken on 07/23/2016 at 0600 MDT

Freezing level.................. 16372 ft MSL (11533 ft AGL)
Convective condensation level... 16010 ft MSL (11171 ft AGL)
Lifted condensation level....... 16973 ft MSL (12134 ft AGL)
Lifted index.................... -2.9
K index......................... +23.5

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  -66.7 -88.1   270   21   11  -1.6  -0.9   81.6 178.9    26.2      M    M
 45000  -59.7 -75.5   235   31   16 -14.1  -7.7   69.0 156.2    20.2      M    M
 40000  -51.5 -60.7   230   43   22   9.1   5.0   58.8 137.9    14.8      M    M
 38000  -47.4 -53.3   235   44   23   6.1   3.4   56.3 133.4    13.5      M    M
 36000  -41.5 -42.7   230   40   21   9.0   5.0   55.3 131.5    13.1      M    M
 34000  -36.7 -34.1   230   38   20   8.0   4.4   53.7 128.7    12.3      M    M
 32000  -31.8 -25.2   235   36   19   7.6   4.1   52.5 126.5    11.7      M    M
 30000  -27.2 -17.0   245   39   20   6.6   3.6   50.8 123.4    10.7      M    M
 29000  -25.7 -14.3   230   32   16   4.2   2.3   49.0 120.3     9.4      M    M
 28000  -24.4 -11.9   240   28   14  -4.3  -2.4   46.8 116.3     7.9      M    M
 27000  -23.0  -9.4   255   25   13   7.0   3.9   45.0 113.0     6.5      M    M
 26000  -20.4  -4.7   275   25   13   5.7   3.1   44.5 112.1     6.2      M    M
 25000  -17.9  -0.2   275   24   12   8.9   4.9   44.0 111.2     5.8      M    M
 24000  -15.3   4.5   275   22   11   8.0   4.4   43.5 110.3     5.5      M    M
 23000  -13.1   8.4   275   20   10   7.9   4.3   42.6 108.8     4.8      M    M
 22000  -10.9  12.4   275   17    9   6.0   3.3   41.8 107.2     4.2      M    M
 21000   -9.3  15.3   295   12    6   1.5   0.8   40.2 104.4     2.9      M    M
 20000   -7.9  17.8   330   11    6   9.3   5.1   37.7  99.9     0.6      M    M
 19500   -6.8  19.8   335   11    6   5.9   3.2   37.4  99.3     0.3      M    M
 19000   -6.0  21.2   310   14    7   6.3   3.4   36.8  98.2    -0.3   1298  6.6
 18500   -5.0  23.0   300   15    8   8.9   4.9   36.3  97.3    -0.9   1255  6.4
 18000   -3.8  25.2   295   16    8   6.9   3.8   36.1  96.9    -1.1   1204  6.1
 17500   -2.7  27.1   295   15    7   8.6   4.7   35.8  96.4    -1.4   1155  5.9
 17000   -1.6  29.1   295   13    7   8.9   4.9   35.5  95.9    -1.8   1107  5.6
 16500   -0.2  31.6   295   12    6   9.4   5.1   35.4  95.8    -1.9   1050  5.3
 16000    1.2  34.2   295   11    6   9.4   5.2   35.4  95.7    -1.9    993  5.0
 15500    2.7  36.9   290   12    6   9.4   5.2   35.3  95.5    -2.0    936  4.8
 15000    4.1  39.4   290   12    6   9.4   5.2   35.2  95.4    -2.1    879  4.5
 14500    5.5  41.9   285   13    6   9.4   5.1   35.2  95.3    -2.2    822  4.2
 14000    6.9  44.4   285   13    7   8.8   4.8   35.1  95.2    -2.2    766  3.9
 13500    8.1  46.6   285   15    8   8.3   4.6   34.9  94.8    -2.5    714  3.6
 13000    9.3  48.7   285   16    8   8.3   4.5   34.7  94.4    -2.7    662  3.4
 12500   10.6  51.1   275   13    7   8.3   4.5   34.4  94.0    -2.9    610  3.1
 12000   11.8  53.2   265   10    5   8.3   4.5   34.2  93.6    -3.1    558  2.8
 11500   13.1  55.6   265   12    6   8.3   4.5   34.0  93.1    -3.4    506  2.6
 11000   14.3  57.7   265   13    7   8.3   4.6   33.7  92.7    -3.6    454  2.3
 10500   15.5  59.9   245   10    5   8.7   4.8   33.5  92.2    -3.9    402  2.0
 10250   16.0  60.8   245    9    4   3.9   2.1   33.3  91.9    -4.1    380  1.9
 10000   16.0  60.8   240    7    4  -0.1  -0.0   32.6  90.6    -4.9    373  1.9
  9750   16.1  61.0   240    6    3   6.0   3.3   32.0  89.6    -5.5    362  1.8
  9500   16.8  62.2   235    5    2   9.2   5.1   31.9  89.4    -5.6    335  1.7
  9250   17.4  63.3   225    3    2   8.6   4.7   31.8  89.2    -5.7    309  1.6
  9000   18.0  64.4   205    2    1   8.0   4.4   31.7  89.1    -5.8    282  1.4
  8750   18.5  65.3   175    5    2   5.1   2.8   31.5  88.6    -6.1    260  1.3
  8500   18.8  65.8   170    8    4   3.8   2.1   31.0  87.8    -6.6    245  1.2
  8250   19.1  66.4   165   11    6   4.2   2.3   30.6  87.1    -7.0    229  1.2
  8000   19.3  66.7   165   14    7   4.1   2.3   30.2  86.3    -7.5    213  1.1
  7750   19.6  67.3   160   16    8   4.1   2.3   29.7  85.5    -8.0    198  1.0
  7500   19.9  67.8   155   18    9   4.2   2.3   29.3  84.7    -8.4    182  0.9
  7250   20.2  68.4   155   19   10   4.2   2.3   28.9  84.0    -8.9    166  0.8
  7000   20.5  68.9   150   21   11   4.2   2.3   28.4  83.2    -9.4    151  0.8
  6750   20.7  69.3   150   22   11   4.2   2.3   28.0  82.4    -9.9    135  0.7
  6500   21.0  69.8   145   23   12   4.2   2.3   27.6  81.6   -10.4    119  0.6
  6250   21.3  70.3   145   24   12   4.1   2.2   27.2  80.9   -10.8    104  0.5
  6000   21.6  70.9   140   25   13   4.7   2.6   26.7  80.1   -11.3     88  0.4
  5750   21.6  70.9   140   23   12  -5.9  -3.3   26.1  79.0   -12.0     78  0.4
  5500   21.0  69.8   135   20   11  -2.7  -1.5   24.7  76.5   -13.4     91  0.5
  5250   21.4  70.5   130   18    9   8.7   4.8   24.4  76.0   -13.8     71  0.4
  5000   21.5  70.7   120   16    8  -8.3  -4.6   23.8  74.9   -14.4     61  0.3

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

           07/23/2016 at 0900 MDT          |       07/23/2016 at 1200 MDT
                                           |
K index... +29.5  LI... +269.7             | K index... +28.5  LI... +268.1
CAPE... +732.2  CIN... -68.8               | CAPE... +1289.9  CIN... -46.4
                                           |
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 -64.4 -83.9  260  16  8   1.5   0.8 | -64.7 -84.5  260  17  9   1.6   0.9
 45000 -60.1 -76.2  255  26 13   5.4   2.9 | -60.1 -76.2  260  27 14   5.6   3.1
 40000 -51.1 -60.0  240  43 22   7.5   4.1 | -50.7 -59.3  250  42 21   7.4   4.1
 38000 -46.6 -51.9  240  43 22   7.5   4.1 | -46.3 -51.3  245  42 22   7.4   4.1
 36000 -42.1 -43.8  245  43 22   8.1   4.4 | -41.9 -43.4  240  43 22   7.9   4.4
 34000 -37.1 -34.8  245  42 22   8.3   4.6 | -37.0 -34.6  245  41 21   8.2   4.5
 32000 -32.1 -25.8  245  41 21   8.4   4.6 | -32.1 -25.8  245  39 20   8.3   4.5
 30000 -28.5 -19.3  250  35 18   5.8   3.2 | -28.6 -19.5  250  31 16   5.7   3.1
 29000 -26.7 -16.1  250  32 16   5.8   3.2 | -26.8 -16.2  250  27 14   5.7   3.1
 28000 -24.9 -12.8  255  29 15   6.9   3.8 | -25.1 -13.2  255  23 12   7.0   3.8
 27000 -22.9  -9.2  260  27 14   7.0   3.8 | -22.4  -8.3  260  23 12   7.0   3.9
 26000 -20.3  -4.5  265  25 13   7.0   3.8 | -20.3  -4.5  260  22 11   7.0   3.9
 25000 -18.2  -0.8  270  23 12   6.9   3.8 | -18.3  -0.9  260  22 11   6.4   3.5
 24000 -16.1   3.0  270  21 11   6.9   3.8 | -16.4   2.5  265  21 11   6.3   3.5
 23000 -14.1   6.6  275  19 10   6.9   3.8 | -14.5   5.9  265  20 10   6.4   3.5
 22000 -12.0  10.4  280  17  9   7.1   3.9 | -12.6   9.3  265  19 10   7.8   4.3
 21000  -9.9  14.2  280  15  8   7.2   4.0 | -10.3  13.5  265  19 10   7.8   4.3
 20000  -7.8  18.0  280  13  7   7.3   4.0 |  -8.0  17.6  265  18  9   7.9   4.3
 19500  -6.8  19.8  285  12  6   7.6   4.1 |  -6.8  19.8  265  18  9   8.0   4.4
 19000  -5.7  21.7  285  12  6   7.9   4.3 |  -5.7  21.7  270  18  9   8.3   4.6
 18500  -4.5  23.9  290  12  6   7.9   4.4 |  -4.5  23.9  270  17  9   8.4   4.6
 18000  -3.4  25.9  290  12  6   8.5   4.7 |  -3.3  26.1  270  17  9   8.5   4.6
 17500  -2.2  28.0  290  12  6   8.6   4.7 |  -2.1  28.2  275  16  8   8.5   4.7
 17000  -1.0  30.2  290  11  6   8.6   4.7 |  -0.8  30.6  275  15  7   8.7   4.8
 16500   0.3  32.5  285  11  5   8.5   4.7 |   0.5  32.9  275  14  7   9.0   4.9
 16000   1.5  34.7  285  10  5   8.5   4.7 |   1.8  35.2  275  13  7   9.0   4.9
 15500   2.7  36.9  285   9  5   9.1   5.0 |   3.1  37.6  275  13  7   9.2   5.0
 15000   4.1  39.4  280   9  5   9.0   5.0 |   4.4  39.9  275  13  7   9.2   5.0
 14500   5.4  41.7  280   8  4   8.7   4.8 |   5.7  42.3  270  12  6   9.3   5.1
 14000   6.7  44.1  275   8  4   8.6   4.7 |   7.1  44.8  270  12  6   9.2   5.1
 13500   8.0  46.4  270   8  4   8.3   4.6 |   8.4  47.1  270  12  6   8.9   4.9
 13000   9.7  49.5  270   8  4   7.8   4.3 |  10.3  50.5  265  12  6   8.5   4.6
 12500  10.9  51.6  265   8  4   8.1   4.5 |  11.5  52.7  265  11  6   8.3   4.5
 12000  12.1  53.8  270   8  4   8.2   4.5 |  12.7  54.9  260  11  6   8.3   4.5
 11500  13.2  55.8  270   9  4   8.6   4.7 |  13.8  56.8  260  11  5   8.6   4.7
 11000  14.4  57.9  270   8  4   9.0   4.9 |  15.0  59.0  255  10  5   9.2   5.0
 10500  15.5  59.9  270   7  4   5.0   2.7 |  16.0  60.8  250   9  4   5.4   3.0
 10250  15.9  60.6  270   7  3   7.6   4.1 |  16.5  61.7  250   8  4   8.5   4.7
 10000  16.5  61.7  265   6  3  10.2   5.6 |  17.2  63.0  245   7  4   9.8   5.4
  9750  17.1  62.8  260   5  2   9.4   5.2 |  17.8  64.0  240   7  3   9.3   5.1
  9500  17.7  63.9  255   4  2   6.4   3.5 |  18.4  65.1  235   6  3   6.7   3.7
  9250  18.0  64.4  235   3  1   5.8   3.2 |  18.8  65.8  230   5  3   6.5   3.6
  9000  18.5  65.3  205   2  1   7.8   4.3 |  19.3  66.7  220   5  2   8.2   4.5
  8750  19.1  66.4  175   3  1   7.4   4.1 |  19.9  67.8  210   4  2   7.8   4.3
  8500  19.6  67.3  165   4  2   6.8   3.7 |  20.4  68.7  200   4  2   7.9   4.3
  8250  20.1  68.2  160   5  3   6.3   3.5 |  21.0  69.8  190   4  2   8.0   4.4
  8000  20.5  68.9  165   6  3   6.8   3.7 |  21.5  70.7  185   4  2   7.9   4.3
  7750  21.0  69.8  165   7  4   5.9   3.2 |  22.1  71.8  185   4  2   8.5   4.7
  7500  21.3  70.3  165   8  4   3.8   2.1 |  22.8  73.0  185   5  2   9.9   5.4
  7250  21.6  70.9  165   9  4   3.4   1.9 |  23.5  74.3  185   4  2   9.9   5.4
  7000  21.8  71.2  160   9  5   3.0   1.6 |  24.3  75.7  185   4  2  10.7   5.9
  6750  22.0  71.6  160  10  5   2.4   1.3 |  25.1  77.2  185   4  2  11.2   6.1
  6500  22.2  72.0  155   9  5   2.5   1.3 |  25.9  78.6  185   4  2  10.5   5.8
  6250  22.3  72.1  150   8  4   2.9   1.6 |  26.7  80.1  185   4  2  10.7   5.9
  6000  22.5  72.5  145   7  3   1.3   0.7 |  27.5  81.5  185   4  2  10.4   5.7
  5750  22.6  72.7  140   5  3   5.8   3.2 |  28.2  82.8  190   4  2  12.9   7.1
  5500  23.3  73.9  135   5  2  11.9   6.5 |  29.3  84.7  190   4  2  15.4   8.4
  5250  24.0  75.2  130   5  2   7.2   3.9 |  30.4  86.7  190   4  2  13.5   7.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/23/2016 at 1500 MDT          |       07/23/2016 at 1800 MDT
                                           |
K index... +26.9  LI... +268.5             | K index... +19.9  LI... +270.7
CAPE... +1233.2  CIN... -23.5              | CAPE... +462.9  CIN... -41.2
                                           |
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 -64.6 -84.3  250  17  9   1.8   1.0 | -64.4 -83.9  250  18  9   1.1   0.6
 45000 -59.7 -75.5  255  26 13   5.7   3.1 | -60.3 -76.5  250  25 13   5.6   3.1
 40000 -50.4 -58.7  250  39 20   6.8   3.7 | -51.0 -59.8  245  36 19   7.2   4.0
 38000 -46.4 -51.5  245  41 21   6.8   3.7 | -46.7 -52.1  240  38 20   7.2   4.0
 36000 -42.3 -44.1  240  42 22   7.8   4.3 | -42.4 -44.3  240  40 20   8.1   4.4
 34000 -37.4 -35.3  240  40 21   8.2   4.5 | -37.3 -35.1  235  39 20   8.4   4.6
 32000 -32.4 -26.3  235  39 20   8.5   4.7 | -32.3 -26.1  235  39 20   8.6   4.7
 30000 -28.4 -19.1  240  32 16   6.7   3.7 | -28.0 -18.4  235  34 18   7.2   3.9
 29000 -26.3 -15.3  240  28 14   6.7   3.7 | -25.9 -14.6  240  32 17   7.2   3.9
 28000 -24.3 -11.7  245  25 13   7.1   3.9 | -23.7 -10.7  240  30 15   7.1   3.9
 27000 -21.6  -6.9  250  23 12   7.1   3.9 | -21.6  -6.9  245  28 15   7.1   3.9
 26000 -19.5  -3.1  250  22 12   7.1   3.9 | -18.9  -2.0  250  26 14   7.1   3.9
 25000 -17.4   0.7  255  22 11   6.1   3.4 | -16.9   1.6  255  25 13   6.2   3.4
 24000 -15.6   3.9  260  22 11   6.1   3.3 | -15.0   5.0  260  24 12   6.1   3.4
 23000 -13.8   7.2  265  22 11   6.0   3.3 | -13.2   8.2  265  24 12   6.1   3.4
 22000 -12.0  10.4  265  22 11   7.4   4.1 | -11.4  11.5  265  23 12   6.9   3.8
 21000  -9.7  14.5  270  21 11   7.5   4.1 |  -9.3  15.3  270  24 12   7.0   3.8
 20000  -7.5  18.5  270  21 11   7.5   4.1 |  -7.3  18.9  270  24 13   7.1   3.9
 19500  -6.4  20.5  270  21 11   7.8   4.3 |  -6.2  20.8  275  25 13   7.8   4.3
 19000  -5.3  22.5  270  21 11   8.3   4.6 |  -5.0  23.0  275  25 13   8.9   4.9
 18500  -4.1  24.6  270  22 11   8.5   4.7 |  -3.7  25.3  275  24 13   8.9   4.9
 18000  -2.9  26.8  270  22 11   8.5   4.7 |  -2.3  27.9  270  24 12   9.1   5.0
 17500  -1.7  28.9  270  21 11   8.6   4.7 |  -1.0  30.2  270  24 12   9.1   5.0
 17000  -0.5  31.1  275  20 10   8.7   4.8 |   0.3  32.5  270  23 12   9.1   5.0
 16500   0.7  33.3  275  19 10   8.7   4.8 |   1.6  34.9  270  23 12   9.0   4.9
 16000   2.0  35.6  275  18  9   8.7   4.8 |   2.9  37.2  270  22 11   9.0   4.9
 15500   3.3  37.9  275  17  9   9.0   4.9 |   4.2  39.6  270  21 11   9.1   5.0
 15000   4.6  40.3  275  16  8   8.9   4.9 |   5.5  41.9  270  21 11   9.1   5.0
 14500   5.9  42.6  275  15  8   9.3   5.1 |   6.8  44.2  270  20 10   9.2   5.0
 14000   7.3  45.1  275  15  8   9.3   5.1 |   8.2  46.8  270  19 10   9.2   5.0
 13500   8.7  47.7  275  14  7   9.2   5.0 |   9.5  49.1  270  18  9   9.1   5.0
 13000  10.7  51.3  275  13  7   9.0   5.0 |  11.5  52.7  275  17  9   8.9   4.9
 12500  12.0  53.6  270  13  7   9.0   5.0 |  12.8  55.0  275  16  8   9.0   4.9
 12000  13.3  55.9  270  13  7   9.1   5.0 |  14.1  57.4  275  15  8   9.0   4.9
 11500  14.6  58.3  265  12  6   9.1   5.0 |  15.4  59.7  280  14  7   9.0   4.9
 11000  15.9  60.6  265  12  6   9.8   5.4 |  16.6  61.9  280  12  6   9.6   5.3
 10500  16.9  62.4  260  12  6   5.5   3.0 |  17.6  63.7  285  10  5   5.6   3.1
 10250  17.4  63.3  260  11  6  10.1   5.5 |  18.2  64.8  285   9  5  10.0   5.5
 10000  18.2  64.8  255  10  5  10.5   5.8 |  19.0  66.2  285   9  5  10.2   5.6
  9750  18.9  66.0  255  10  5  10.4   5.7 |  19.7  67.5  285   8  4  10.8   5.9
  9500  19.6  67.3  255   9  5   8.3   4.5 |  20.5  68.9  285   8  4   7.5   4.1
  9250  20.1  68.2  250   8  4   8.0   4.4 |  20.9  69.6  285   6  3   6.5   3.6
  9000  20.7  69.3  250   8  4   9.3   5.1 |  21.4  70.5  285   5  3   9.0   4.9
  8750  21.3  70.3  250   7  4   9.1   5.0 |  22.0  71.6  285   4  2   8.4   4.6
  8500  22.0  71.6  245   7  4   9.9   5.4 |  22.6  72.7  280   4  2   9.3   5.1
  8250  22.7  72.9  245   7  3  10.2   5.6 |  23.3  73.9  280   4  2   9.8   5.4
  8000  23.4  74.1  245   7  3   9.9   5.4 |  24.0  75.2  275   3  2   9.6   5.3
  7750  24.1  75.4  245   6  3   9.9   5.4 |  24.6  76.3  275   3  2   9.7   5.3
  7500  24.8  76.6  245   6  3  10.1   5.6 |  25.4  77.7  270   3  2  10.0   5.5
  7250  25.6  78.1  245   6  3  10.3   5.6 |  26.1  79.0  270   3  2  10.6   5.8
  7000  26.3  79.3  245   6  3  10.0   5.5 |  26.9  80.4  270   3  2   9.4   5.2
  6750  27.1  80.8  245   6  3  10.3   5.6 |  27.6  81.7  265   3  2   9.1   5.0
  6500  27.9  82.2  245   6  3  10.8   5.9 |  28.3  82.9  265   3  2  10.4   5.7
  6250  28.7  83.7  245   6  3  11.0   6.0 |  29.1  84.4  265   3  2  11.0   6.0
  6000  29.5  85.1  245   6  3  10.2   5.6 |  29.9  85.8  265   3  2   9.7   5.3
  5750  30.2  86.4  240   6  3  12.7   7.0 |  30.6  87.1  260   3  1  10.0   5.5
  5500  31.4  88.5  245   6  3  16.1   8.9 |  31.4  88.5  265   3  1  11.8   6.5
  5250  32.5  90.5  245   6  3  13.5   7.4 |  32.2  90.0  265   3  1  10.8   5.9
  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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