Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 241226
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0626 MDT Saturday, September 24, 2016

This forecast is for Saturday, September 24, 2016:

If the trigger temperature of 54.7 F/12.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 400 ft/min (2.0 m/s)
   Maximum height of thermals.................. 14926 ft MSL (10087 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12968 ft MSL (8129 ft AGL)
Thermal soaring outlook for Sunday 09/25....... Good

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

Remarks...

Sunrise/Sunset.................... 07:04:10 / 19:08:34 MDT
Total possible sunshine........... 12 hr 4 min 25 sec (724 min 25 sec)
Altitude of sun at 13:05:53 MDT... 50.03 degrees

Upper air data from rawinsonde observation taken on 09/24/2016 at 0600 MDT

Freezing level.................. 9150 ft MSL (4311 ft AGL)
Convective condensation level... 10476 ft MSL (5637 ft AGL)
Lifted condensation level....... 12718 ft MSL (7879 ft AGL)
Lifted index.................... -0.2
K index......................... +19.6

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  -57.0 -70.6   275   26   13   3.0   1.7  103.0 217.4    48.0      M    M
 45000  -50.4 -58.7   275   25   13   3.9   2.2   88.2 190.8    42.4      M    M
 40000  -43.3 -45.9   300   43   22   4.9   2.7   76.5 169.6    37.5      M    M
 38000  -41.6 -42.9   280   36   19   2.2   1.2   70.1 158.2    34.2      M    M
 36000  -38.8 -37.8   295   37   19   6.0   3.3   65.7 150.3    32.0      M    M
 34000  -39.1 -38.4   285   36   18   0.1   0.0   57.0 134.5    26.6      M    M
 32000  -39.9 -39.8   290   33   17   0.2   0.1   46.6 116.0    19.8      M    M
 30000  -41.3 -42.3   320   48   25  -9.6  -5.2   36.9  98.4    13.1      M    M
 29000  -41.7 -43.1   320   66   34   7.3   4.0   32.4  90.4     9.8      M    M
 28000  -39.2 -38.6   315   59   30   8.3   4.5   31.9  89.4     9.5      M    M
 27000  -36.7 -34.1   310   52   27   8.7   4.7   31.4  88.4     9.2      M    M
 26000  -34.1 -29.4   305   46   24   8.7   4.8   31.0  87.7     9.0      M    M
 25000  -31.6 -24.9   295   41   21   8.2   4.5   30.5  86.9     8.7      M    M
 24000  -29.1 -20.4   295   38   20   8.1   4.4   29.9  85.8     8.3      M    M
 23000  -26.8 -16.2   285   33   17   8.0   4.4   29.3  84.7     7.9      M    M
 22000  -24.4 -11.9   280   32   17   8.0   4.4   28.6  83.5     7.4      M    M
 21000  -22.2  -8.0   270   32   16   7.2   4.0   27.8  82.0     6.8      M    M
 20000  -20.1  -4.2   270   30   16   7.2   4.0   26.9  80.4     6.1      M    M
 19500  -19.0  -2.2   270   30   16   7.2   4.0   26.4  79.5     5.7      M    M
 19000  -17.9  -0.2   265   31   16   7.3   4.0   25.9  78.7     5.4      M    M
 18500  -16.9   1.6   265   31   16   7.6   4.2   25.5  77.9     5.0      M    M
 18000  -15.1   4.8   265   32   17   8.3   4.6   25.0  77.0     4.6      M    M
 17500  -14.2   6.4   265   33   17   3.8   2.1   24.4  75.9     4.1      M    M
 17000  -13.6   7.5   265   34   18   4.5   2.5   23.5  74.2     3.2      M    M
 16500  -12.8   9.0   265   35   18   4.8   2.7   22.6  72.7     2.6      M    M
 16000  -12.1  10.2   265   36   18   4.9   2.7   21.8  71.2     1.9      M    M
 15500  -11.5  11.3   265   33   17   3.9   2.1   20.9  69.6     1.0      M    M
 15000  -11.0  12.2   270   30   15   2.9   1.6   19.8  67.7     0.0      M    M
 14500  -10.4  13.3   270   27   14   5.6   3.1   18.9  66.0    -0.9    767  3.9
 14000   -9.7  14.5   275   25   13   5.3   2.9   18.2  64.7    -1.6    730  3.7
 13500   -8.9  16.0   270   24   12   5.3   2.9   17.4  63.3    -2.3    693  3.5
 13000   -8.2  17.2   265   23   12   5.5   3.0   16.7  62.0    -3.0    655  3.3
 12500   -7.2  19.0   260   22   12   7.5   4.1   16.2  61.1    -3.5    611  3.1
 12000   -6.1  21.0   255   22   11   7.4   4.0   15.8  60.5    -3.9    564  2.9
 11500   -5.1  22.8   250   23   12   7.4   4.0   15.4  59.7    -4.4    517  2.6
 11000   -4.0  24.8   250   24   12   7.4   4.0   15.0  59.0    -4.8    471  2.4
 10500   -2.9  26.8   245   25   13   7.4   4.1   14.6  58.3    -5.2    424  2.2
 10250   -2.4  27.7   245   26   13   7.4   4.1   14.5  58.0    -5.4    401  2.0
 10000   -1.9  28.6   245   25   13   7.3   4.0   14.3  57.7    -5.6    377  1.9
  9750   -1.3  29.7   245   24   12   7.1   3.9   14.1  57.3    -5.8    354  1.8
  9500   -0.8  30.6   245   23   12   7.2   3.9   13.9  56.9    -6.0    331  1.7
  9250   -0.3  31.5   250   21   11   7.1   3.9   13.7  56.6    -6.2    307  1.6
  9000    0.3  32.5   250   20   10   7.3   4.0   13.5  56.2    -6.4    284  1.4
  8750    0.9  33.6   250   19   10   8.4   4.6   13.3  56.0    -6.6    259  1.3
  8500    1.5  34.7   245   18    9   8.9   4.9   13.2  55.8    -6.7    232  1.2
  8250    2.2  36.0   245   16    8   8.8   4.8   13.2  55.7    -6.8    205  1.0
  8000    2.8  37.0   240   15    8   8.8   4.9   13.1  55.6    -6.9    178  0.9
  7750    3.5  38.3   240   14    7   8.8   4.8   13.0  55.5    -7.0    151  0.8
  7500    4.1  39.4   235   12    6   8.8   4.8   13.0  55.4    -7.0    123  0.6
  7250    4.8  40.6   230   11    6   8.8   4.8   12.9  55.2    -7.1     96  0.5
  7000    5.5  41.9   225    9    5   8.9   4.9   12.8  55.1    -7.2     69  0.4
  6750    6.1  43.0   210    9    5   8.8   4.8   12.8  55.0    -7.3     42  0.2
  6500    6.8  44.2   195   10    5   9.1   5.0   12.7  54.8    -7.4     15  0.1
  6250    7.4  45.3   180   11    6   8.0   4.4   12.6  54.7    -7.5      M    M
  6000    7.9  46.2   170   12    6   4.1   2.2   12.3  54.2    -7.8      M    M
  5750    8.0  46.4   165   11    6   2.3   1.2   11.8  53.2    -8.4      M    M
  5500    8.2  46.8   155    9    5   2.8   1.6   11.3  52.3    -9.0      M    M
  5250    8.3  46.9   135    7    4   2.5   1.4   10.7  51.3    -9.6      M    M
  5000    8.5  47.3   110    7    3   3.5   1.9   10.2  50.4   -10.2      M    M

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

           09/24/2016 at 0900 MDT          |       09/24/2016 at 1200 MDT
                                           |
K index... +21.8  LI... +276.7             | K index... +17.8  LI... +277.9
CAPE... 0.0  CIN... -2.3                   | CAPE... +7.3  CIN... M
                                           |
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 -57.3 -71.1  320  26 13   4.3   2.4 | -57.6 -71.7  305  19 10   4.1   2.2
 45000 -50.4 -58.7  315  37 19   5.7   3.2 | -51.1 -60.0  300  29 15   5.3   2.9
 40000 -41.4 -42.5  310  39 20   5.2   2.9 | -43.2 -45.8  300  30 15   5.7   3.1
 38000 -39.8 -39.6  310  36 18   2.4   1.3 | -41.8 -43.2  310  27 14   1.7   0.9
 36000 -38.4 -37.1  310  33 17   2.4   1.3 | -40.8 -41.4  325  25 13   1.7   0.9
 34000 -38.2 -36.8  315  32 17  -3.4  -1.9 | -40.6 -41.1  340  25 13  -1.5  -0.8
 32000 -40.2 -40.4  325  37 19  -3.4  -1.8 | -41.5 -42.7  360  29 15  -1.5  -0.8
 30000 -40.7 -41.3  325  41 21   5.2   2.9 | -40.4 -40.7  010  34 17   7.2   3.9
 29000 -39.1 -38.4  320  41 21   5.4   3.0 | -38.3 -36.9  010  35 18   7.1   3.9
 28000 -37.5 -35.5  320  42 22   5.5   3.0 | -36.2 -33.2  010  36 19   7.1   3.9
 27000 -35.8 -32.4  315  43 22   7.6   4.2 | -34.0 -29.2  005  37 19   7.9   4.3
 26000 -32.6 -26.7  310  40 20   8.6   4.7 | -31.7 -25.1  360  37 19   7.8   4.3
 25000 -30.0 -22.0  310  37 19   8.6   4.7 | -29.3 -20.7  355  36 19   7.8   4.3
 24000 -27.5 -17.5  310  35 18   7.5   4.1 | -27.0 -16.6  350  36 19   8.2   4.5
 23000 -25.3 -13.5  305  33 17   7.4   4.1 | -24.5 -12.1  345  36 18   8.2   4.5
 22000 -23.1  -9.6  305  32 16   7.4   4.1 | -21.4  -6.5  340  36 18   8.2   4.5
 21000 -20.9  -5.6  305  31 16   7.6   4.2 | -19.0  -2.2  335  34 17   8.4   4.6
 20000 -18.7  -1.7  300  32 16   7.6   4.2 | -16.5   2.3  335  29 15   8.4   4.6
 19500 -17.6   0.3  300  33 17   7.7   4.2 | -15.2   4.6  335  27 14   8.4   4.6
 19000 -16.5   2.3  300  33 17   7.8   4.3 | -13.9   7.0  335  25 13   8.0   4.4
 18500 -15.4   4.3  300  34 17   6.6   3.6 | -12.9   8.8  330  24 12   6.4   3.5
 18000 -14.5   5.9  295  35 18   6.5   3.6 | -12.0  10.4  330  23 12   6.6   3.6
 17500 -13.5   7.7  295  36 18   6.1   3.3 | -11.1  12.0  325  22 12   5.4   3.0
 17000 -12.8   9.0  290  36 18   4.9   2.7 | -10.3  13.5  325  22 11   5.3   2.9
 16500 -12.1  10.2  285  35 18   5.0   2.7 |  -9.6  14.7  320  21 11   4.9   2.7
 16000 -11.4  11.5  280  35 18   4.7   2.6 |  -8.9  16.0  320  21 11   4.4   2.4
 15500 -10.7  12.7  275  34 17   4.7   2.6 |  -8.3  17.1  315  20 10   4.4   2.4
 15000  -9.9  14.2  275  33 17   5.3   2.9 |  -7.7  18.1  310  20 10   4.0   2.2
 14500  -9.2  15.4  270  31 16   5.4   2.9 |  -7.2  19.0  305  20 10   4.1   2.3
 14000  -8.4  16.9  270  29 15   5.3   2.9 |  -6.6  20.1  305  19 10   3.2   1.8
 13500  -7.6  18.3  270  27 14   5.3   2.9 |  -6.2  20.8  300  18  9   3.2   1.8
 13000  -6.5  20.3  270  23 12   5.1   2.8 |  -5.7  21.7  295  17  9   3.9   2.1
 12500  -5.8  21.6  270  20 10   5.1   2.8 |  -5.1  22.8  290  16  8   3.9   2.1
 12000  -5.0  23.0  270  18  9   5.6   3.1 |  -4.5  23.9  285  15  8   5.5   3.0
 11500  -4.2  24.4  270  17  9   5.6   3.1 |  -3.6  25.5  285  13  7   5.8   3.2
 11000  -3.4  25.9  270  15  8   5.9   3.2 |  -2.8  27.0  280  12  6   5.5   3.0
 10500  -2.5  27.5  270  14  7   6.6   3.6 |  -2.0  28.4  280  11  6   6.0   3.3
 10250  -2.1  28.2  265  14  7   2.9   1.6 |  -1.6  29.1  280  11  5   3.3   1.8
 10000  -2.0  28.4  265  13  7   3.3   1.8 |  -1.5  29.3  280  10  5   4.2   2.3
  9750  -1.5  29.3  265  13  7   7.3   4.0 |  -1.0  30.2  275  10  5   7.8   4.3
  9500  -1.1  30.0  260  13  7   6.4   3.5 |  -0.4  31.3  275  10  5   7.7   4.2
  9250  -0.6  30.9  260  13  7   5.2   2.9 |   0.1  32.2  275  10  5   5.7   3.1
  9000  -0.3  31.5  255  14  7   6.3   3.5 |   0.4  32.7  270  10  5   4.1   2.3
  8750   0.3  32.5  250  14  7   8.5   4.6 |   0.8  33.4  265  10  5   6.5   3.6
  8500   0.9  33.6  250  15  8   8.5   4.7 |   1.3  34.3  265  11  5   7.0   3.9
  8250   1.6  34.9  250  15  8   9.7   5.3 |   1.8  35.2  260  11  6   6.4   3.5
  8000   2.3  36.1  250  15  8   9.9   5.4 |   2.3  36.1  260  10  5   6.3   3.5
  7750   3.1  37.6  245  15  8  10.0   5.5 |   2.7  36.9  265   9  5   6.1   3.4
  7500   3.8  38.8  245  15  8   8.8   4.8 |   3.1  37.6  265   7  4   7.9   4.3
  7250   4.4  39.9  245  13  7   7.6   4.2 |   3.8  38.8  265   6  3  10.1   5.5
  7000   4.9  40.8  240  12  6   7.9   4.3 |   4.6  40.3  270   6  3  10.2   5.6
  6750   5.5  41.9  235  10  5   7.3   4.0 |   5.3  41.5  270   6  3   9.7   5.3
  6500   6.0  42.8  230   9  5   6.9   3.8 |   6.0  42.8  270   5  3  10.2   5.6
  6250   6.5  43.7  225   8  4   7.1   3.9 |   6.8  44.2  270   5  3  11.3   6.2
  6000   7.0  44.6  215   6  3   6.1   3.3 |   7.6  45.7  270   5  3  10.1   5.5
  5750   7.4  45.3  205   5  3   6.5   3.6 |   8.5  47.3  270   5  3  13.7   7.5
  5500   7.9  46.2  210   5  3   8.2   4.5 |   9.8  49.6  270   5  3  23.2  12.7
  5250   8.5  47.3  210   5  3   6.8   3.7 |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/24/2016 at 1500 MDT          |       09/24/2016 at 1800 MDT
                                           |
K index... +17.9  LI... +277.9             | K index... +17.1  LI... +276.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -58.3 -72.9  295  14  7   4.9   2.7 | -58.6 -73.5  300  13  7   4.2   2.3
 45000 -50.8 -59.4  295  21 11   4.6   2.5 | -51.8 -61.2  300  15  8   4.5   2.5
 40000 -43.9 -47.0  315  23 12   3.2   1.8 | -45.1 -49.2  325  11  6   2.3   1.3
 38000 -43.5 -46.3  335  24 12   0.6   0.3 | -45.1 -49.2  355  20 10   0.1   0.1
 36000 -43.2 -45.8  350  26 14   0.6   0.3 | -45.0 -49.0  005  32 16   0.1   0.1
 34000 -42.8 -45.0  005  30 16   0.7   0.4 | -43.8 -46.8  005  36 19   3.8   2.1
 32000 -42.4 -44.3  015  34 17   0.7   0.4 | -41.3 -42.3  360  34 18   3.7   2.1
 30000 -39.4 -38.9  015  35 18   8.4   4.6 | -37.6 -35.7  005  30 15   7.8   4.3
 29000 -36.9 -34.4  015  34 18   8.4   4.6 | -35.3 -31.5  005  27 14   7.8   4.3
 28000 -34.4 -29.9  015  33 17   8.4   4.6 | -33.0 -27.4  010  24 12   7.8   4.3
 27000 -32.0 -25.6  010  33 17   7.6   4.2 | -30.5 -22.9  005  23 12   8.6   4.7
 26000 -29.8 -21.6  005  33 17   7.6   4.2 | -27.9 -18.2  355  23 12   8.7   4.7
 25000 -27.5 -17.5  355  34 18   7.6   4.2 | -25.3 -13.5  350  25 13   8.6   4.7
 24000 -25.2 -13.4  350  34 18   8.7   4.8 | -22.8  -9.0  345  24 12   7.7   4.2
 23000 -22.6  -8.7  350  31 16   8.6   4.7 | -20.6  -5.1  340  21 11   7.7   4.2
 22000 -20.0  -4.0  345  27 14   8.6   4.7 | -18.3  -0.9  340  18  9   7.8   4.3
 21000 -17.6   0.3  340  25 13   8.0   4.4 | -16.2   2.8  335  17  9   6.6   3.6
 20000 -15.2   4.6  340  23 12   8.0   4.4 | -14.2   6.4  330  16  8   6.6   3.6
 19500 -14.0   6.8  340  23 12   8.0   4.4 | -13.3   8.1  325  16  8   6.6   3.6
 19000 -12.9   8.8  335  22 11   8.2   4.5 | -12.3   9.9  320  16  8   6.6   3.6
 18500 -12.0  10.4  335  21 11   3.7   2.0 | -11.3  11.7  315  16  8   6.6   3.6
 18000 -11.1  12.0  325  20 11   4.2   2.3 |  -9.9  14.2  315  17  9   6.3   3.5
 17500 -10.5  13.1  325  20 10   4.3   2.4 |  -9.1  15.6  315  17  9   4.0   2.2
 17000  -9.9  14.2  325  20 10   4.3   2.4 |  -8.5  16.7  315  16  8   4.2   2.3
 16500  -9.2  15.4  325  20 10   4.9   2.7 |  -8.0  17.6  315  16  8   3.6   2.0
 16000  -8.5  16.7  330  20 10   5.1   2.8 |  -7.5  18.5  320  16  8   3.6   2.0
 15500  -7.8  18.0  330  19 10   5.4   2.9 |  -7.0  19.4  320  16  8   4.4   2.4
 15000  -6.9  19.6  330  19 10   6.0   3.3 |  -6.2  20.8  325  16  8   5.3   2.9
 14500  -6.1  21.0  335  19 10   6.0   3.3 |  -5.5  22.1  325  15  8   5.5   3.0
 14000  -5.2  22.6  335  19 10   6.3   3.5 |  -4.6  23.7  335  15  8   6.4   3.5
 13500  -4.2  24.4  335  19 10   6.3   3.5 |  -3.7  25.3  340  16  8   6.4   3.5
 13000  -3.3  26.1  335  19 10   6.1   3.4 |  -2.7  27.1  345  16  8   6.5   3.6
 12500  -2.4  27.7  335  18  9   6.2   3.4 |  -1.8  28.8  345  17  9   6.5   3.6
 12000  -1.6  29.1  335  17  9   5.8   3.2 |  -0.8  30.6  345  17  9   7.0   3.8
 11500  -0.7  30.7  330  15  8   6.0   3.3 |   0.2  32.4  345  16  8   7.0   3.8
 11000   0.1  32.2  330  13  7   4.9   2.7 |   1.2  34.2  345  15  8   6.9   3.8
 10500   0.8  33.4  325  11  5   5.6   3.1 |   2.2  36.0  340  13  7   7.4   4.0
 10250   1.1  34.0  320  10  5   2.1   1.2 |   2.6  36.7  340  12  6   3.6   2.0
 10000   1.2  34.2  320   9  5   3.4   1.9 |   2.8  37.0  340  11  6   5.0   2.7
  9750   1.7  35.1  315   9  4   7.7   4.2 |   3.4  38.1  335  11  5   9.3   5.1
  9500   2.2  36.0  310   8  4   6.7   3.7 |   4.0  39.2  335  10  5   8.1   4.4
  9250   2.7  36.9  310   8  4   5.4   3.0 |   4.5  40.1  335   9  5   6.2   3.4
  9000   3.0  37.4  305   8  4   5.0   2.8 |   4.9  40.8  335   8  4   5.4   3.0
  8750   3.5  38.3  305   7  4   6.8   3.7 |   5.4  41.7  335   7  4   6.7   3.7
  8500   3.9  39.0  300   7  3   6.6   3.6 |   5.8  42.4  335   6  3   6.4   3.5
  8250   4.4  39.9  300   6  3   5.6   3.1 |   6.3  43.3  330   5  3   6.0   3.3
  8000   4.7  40.5  300   5  3   5.6   3.1 |   6.7  44.1  330   4  2   5.9   3.2
  7750   5.2  41.4  300   5  2   7.2   4.0 |   7.2  45.0  325   3  1   5.1   2.8
  7500   5.7  42.3  300   4  2   9.3   5.1 |   7.5  45.5  315   2  1   6.4   3.5
  7250   6.5  43.7  300   4  2  10.3   5.7 |   8.1  46.6  305   2  1   8.0   4.4
  7000   7.2  45.0  300   4  2  10.2   5.6 |   8.7  47.7  300   1  1   7.6   4.2
  6750   8.0  46.4  295   4  2   9.9   5.4 |   9.2  48.6  290   1  1   8.4   4.6
  6500   8.7  47.7  295   4  2  10.4   5.7 |   9.9  49.8  285   1  1   9.7   5.3
  6250   9.5  49.1  295   4  2  12.0   6.6 |  10.7  51.3  280   1  1  10.1   5.5
  6000  10.4  50.7  295   4  2   9.1   5.0 |  11.4  52.5  275   1  1  10.1   5.5
  5750  11.1  52.0  295   4  2  14.8   8.1 |  12.2  54.0  270   1  1  12.6   6.9
  5500  12.8  55.0  295   4  2  31.5  17.3 |  13.3  55.9  275   1  1  16.5   9.0
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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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