Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 161225
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0625 MDT Tuesday, September 16, 2014

This forecast is for Tuesday, September 16, 2014:

If the trigger temperature of 84.0 F/28.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1158 ft/min (5.9 m/s)
   Maximum height of thermals.................. 16738 ft MSL (11899 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1315 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................. 7786 ft MSL (2947 ft AGL)
Thermal soaring outlook for Wednesday 09/17.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:56:23 / 19:22:19 MDT
Total possible sunshine........... 12 hr 25 min 56 sec (745 min 56 sec)
Altitude of sun at 13:08:52 MDT... 53.34 degrees

Upper air data from rawinsonde observation taken on 09/16/2014 at 0600 MDT

Freezing level.................. 14949 ft MSL (10110 ft AGL)
Convective condensation level... 16041 ft MSL (11202 ft AGL)
Lifted condensation level....... 16168 ft MSL (11328 ft AGL)
Lifted index.................... +1.0
K index......................... +21.4

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  -68.9 -92.0   280   63   32   1.3   0.7   80.4 176.6    28.8      M    M
 45000  -61.6 -78.9   270   72   37   4.3   2.4   66.8 152.2    22.6      M    M
 40000  -53.8 -64.8   270   62   32   3.1   1.7   56.4 133.5    17.2      M    M
 38000  -49.9 -57.8   275   51   26   7.9   4.3   53.3 127.9    15.6      M    M
 36000  -45.2 -49.4   285   39   20   7.8   4.3   51.9 125.4    15.0      M    M
 34000  -40.9 -41.6   295   32   17   5.4   3.0   49.6 121.3    13.7      M    M
 32000  -36.5 -33.7   300   29   15   9.4   5.1   47.7 117.9    12.7      M    M
 30000  -31.2 -24.2   305   30   15   6.3   3.5   46.0 114.8    11.7      M    M
 29000  -29.3 -20.7   310   26   14   7.8   4.3   44.7 112.5    10.9      M    M
 28000  -26.8 -16.2   280   22   11   8.4   4.6   44.2 111.6    10.6      M    M
 27000  -24.2 -11.6   285   22   11   9.0   4.9   43.7 110.7    10.3      M    M
 26000  -21.5  -6.7   290   22   11   9.2   5.1   43.5 110.3    10.3      M    M
 25000  -19.8  -3.6   295   22   11   5.3   2.9   42.0 107.7     9.2      M    M
 24000  -17.2   1.0   275   21   11   8.1   4.5   41.6 106.8     8.9      M    M
 23000  -15.4   4.3   285   18    9   5.3   2.9   40.2 104.4     8.0      M    M
 22000  -13.7   7.3   305   16    8   5.9   3.2   38.7 101.7     6.8      M    M
 21000  -11.9  10.6   325   15    8   5.9   3.3   37.4  99.4     5.8      M    M
 20000  -11.0  12.2   310   16    8  -2.1  -1.1   35.1  95.2     3.8      M    M
 19500  -10.4  13.3   295   17    9  -4.8  -2.6   34.2  93.6     3.0      M    M
 19000  -10.8  12.6   280   17    9  12.1   6.7   32.3  90.1     1.1      M    M
 18500   -9.5  14.9   280   16    8   9.4   5.2   32.2  90.0     1.0      M    M
 18000   -8.1  17.4   280   16    8   8.4   4.6   32.1  89.8     0.9      M    M
 17500   -7.1  19.2   275   15    8   7.5   4.1   31.7  89.0     0.5      M    M
 17000   -6.0  21.2   275   14    7   8.2   4.5   31.4  88.4     0.1      M    M
 16500   -4.0  24.8   285   13    7   8.9   4.9   31.1  88.0    -0.1   1119  5.7
 16000   -2.7  27.1   290   12    6   8.9   4.9   31.0  87.8    -0.2   1064  5.4
 15500   -1.3  29.7   300   12    6   9.5   5.2   30.9  87.6    -0.3   1008  5.1
 15000    0.1  32.2   305   13    7   9.5   5.2   30.9  87.6    -0.3    951  4.8
 14500    1.5  34.7   300   14    7   9.5   5.2   30.9  87.6    -0.3    894  4.5
 14000    2.9  37.2   295   15    8   9.5   5.2   30.9  87.6    -0.4    837  4.3
 13500    4.3  39.7   295   14    7   9.5   5.2   30.8  87.4    -0.5    780  4.0
 13000    5.7  42.3   300   13    7   9.5   5.2   30.8  87.4    -0.5    723  3.7
 12500    7.1  44.8   300   12    6   9.5   5.2   30.7  87.3    -0.6    666  3.4
 12000    8.6  47.5   305   11    6   9.5   5.2   30.7  87.3    -0.6    609  3.1
 11500   10.0  50.0   300   10    5   9.5   5.2   30.6  87.1    -0.7    552  2.8
 11000   11.4  52.5   295    9    5   9.5   5.2   30.6  87.0    -0.8    495  2.5
 10500   12.8  55.0   285    8    4   9.2   5.0   30.5  87.0    -0.8    438  2.2
 10250   13.4  56.1   285    7    4   8.7   4.7   30.4  86.8    -0.9    411  2.1
 10000   14.1  57.4   280    7    3   8.8   4.8   30.4  86.7    -1.0    384  2.0
  9750   14.7  58.5   275    6    3   8.7   4.8   30.3  86.5    -1.1    357  1.8
  9500   15.4  59.7   275    5    3   8.9   4.9   30.2  86.4    -1.1    330  1.7
  9250   16.1  61.0   265    5    2   8.3   4.6   30.1  86.3    -1.2    303  1.5
  9000   16.6  61.9   260    4    2   6.7   3.7   30.0  86.0    -1.4    280  1.4
  8750   17.0  62.6   225    3    2   6.0   3.3   29.7  85.4    -1.7    259  1.3
  8500   17.5  63.5   185    4    2   6.2   3.4   29.4  84.9    -2.0    239  1.2
  8250   17.9  64.2   160    5    3   6.2   3.4   29.1  84.4    -2.3    219  1.1
  8000   18.3  64.9   150    8    4   5.9   3.3   28.9  83.9    -2.6    199  1.0
  7750   18.7  65.7   150   11    6   3.6   2.0   28.5  83.3    -3.0    181  0.9
  7500   18.8  65.8   150   14    7   1.9   1.0   27.9  82.3    -3.6    168  0.9
  7250   19.0  66.2   150   17    9   3.4   1.8   27.4  81.3    -4.1    156  0.8
  7000   19.2  66.6   150   20   10  -0.8  -0.4   26.8  80.3    -4.7    143  0.7
  6750   18.8  65.8   145   19   10  -7.6  -4.1   25.7  78.2    -5.8    146  0.7
  6500   18.4  65.1   140   17    9   0.3   0.2   24.5  76.2    -6.9    151  0.8
  6250   18.8  65.8   135   14    7   7.8   4.3   24.2  75.6    -7.2    131  0.7
  6000   19.3  66.7   125   12    6   6.4   3.5   24.0  75.2    -7.5    110  0.6
  5750   19.8  67.6   115   11    6   7.1   3.9   23.8  74.8    -7.8     88  0.4
  5500   20.3  68.5   110    9    5   5.7   3.2   23.6  74.4    -8.0     66  0.3
  5250   20.0  68.0   100    7    4 -20.0 -11.0   22.6  72.6    -9.1     67  0.3
  5000   17.2  63.0   090    6    3 -49.5 -27.2   19.0  66.2   -12.7    145  0.7

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

           09/16/2014 at 0900 MDT          |       09/16/2014 at 1200 MDT
                                           |
K index... +24.0  LI... -2.6               | K index... +21.2  LI... -3.4
CAPE... +154.5  CIN... -128.9              | CAPE... +397.2  CIN... -63.9
                                           |
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 -66.1 -87.0  280  51 26   1.7   0.9 | -66.7 -88.1  285  52 27   2.2   1.2
 45000 -62.3 -80.1  280  68 35   4.7   2.6 | -62.1 -79.8  280  67 34   5.2   2.9
 40000 -54.4 -65.9  285  52 27   7.1   3.9 | -54.1 -65.4  280  51 26   6.5   3.5
 38000 -50.1 -58.2  285  44 23   7.2   3.9 | -49.7 -57.5  280  40 21   6.4   3.5
 36000 -45.8 -50.4  295  36 19   7.2   4.0 | -45.8 -50.4  285  30 16   6.7   3.7
 34000 -40.8 -41.4  295  34 17   8.3   4.6 | -40.7 -41.3  285  29 15   8.7   4.7
 32000 -35.8 -32.4  300  32 16   8.3   4.6 | -35.5 -31.9  285  28 15   8.8   4.8
 30000 -31.2 -24.2  300  25 13   7.6   4.2 | -31.0 -23.8  285  24 12   7.4   4.1
 29000 -28.9 -20.0  300  22 11   7.6   4.2 | -28.7 -19.7  280  21 11   7.4   4.1
 28000 -26.6 -15.9  300  18  9   7.7   4.2 | -26.5 -15.7  280  19 10   7.6   4.2
 27000 -24.3 -11.7  295  17  9   7.7   4.2 | -24.2 -11.6  280  18  9   7.7   4.2
 26000 -22.0  -7.6  295  17  9   7.7   4.2 | -21.9  -7.4  280  17  9   7.7   4.2
 25000 -19.7  -3.5  290  16  8   7.8   4.3 | -19.6  -3.3  285  16  8   7.7   4.2
 24000 -17.8  -0.0  290  16  8   5.9   3.2 | -17.6   0.3  290  16  8   6.4   3.5
 23000 -16.0   3.2  290  16  8   5.9   3.3 | -15.6   3.9  295  15  8   6.4   3.5
 22000 -13.8   7.2  290  17  9   4.9   2.7 | -13.3   8.1  300  15  8   5.1   2.8
 21000 -12.5   9.5  295  16  8   4.6   2.5 | -11.8  10.8  305  14  7   4.9   2.7
 20000 -11.1  12.0  295  15  8   4.8   2.6 | -10.4  13.3  305  14  7   5.0   2.7
 19500 -10.5  13.1  295  14  7   5.7   3.1 |  -9.7  14.5  305  13  7   5.9   3.2
 19000  -9.4  15.1  300  13  7   7.8   4.3 |  -8.7  16.3  305  13  6   7.5   4.1
 18500  -8.3  17.1  300  12  6   7.7   4.2 |  -7.6  18.3  305  12  6   7.6   4.2
 18000  -7.1  19.2  300  12  6   8.8   4.8 |  -6.5  20.3  300  11  6   8.0   4.4
 17500  -5.9  21.4  300  11  6   8.9   4.9 |  -5.3  22.5  300  10  5   8.0   4.4
 17000  -4.6  23.7  300  11  5   8.7   4.8 |  -4.2  24.4  295  10  5   8.2   4.5
 16500  -3.4  25.9  300  11  5   8.2   4.5 |  -3.0  26.6  295   9  5   8.3   4.6
 16000  -2.3  27.9  300  11  5   8.2   4.5 |  -1.8  28.8  290   8  4   8.4   4.6
 15500  -1.0  30.2  300  11  5   8.9   4.9 |  -0.6  30.9  290   8  4   8.3   4.6
 15000   0.3  32.5  300  11  5   8.9   4.9 |   0.6  33.1  285   8  4   8.3   4.6
 14500   1.6  34.9  295  11  5   8.7   4.8 |   1.9  35.4  285   8  4   8.7   4.8
 14000   2.9  37.2  295  11  6   8.7   4.7 |   3.1  37.6  280   8  4   8.8   4.8
 13500   4.2  39.6  295  11  6   8.7   4.8 |   4.4  39.9  280   8  4   8.7   4.8
 13000   5.5  41.9  290  11  6   8.7   4.8 |   5.6  42.1  275   8  4   8.7   4.8
 12500   6.8  44.2  285  11  6   8.5   4.6 |   6.9  44.4  275   8  4   8.9   4.9
 12000   8.0  46.4  280  11  6   8.1   4.5 |   8.2  46.8  270   8  4   9.1   5.0
 11500   9.2  48.6  275  10  5   7.9   4.3 |   9.6  49.3  270   8  4   8.6   4.7
 11000  10.3  50.5  270   9  4   7.5   4.1 |  10.8  51.4  260   8  4   7.6   4.2
 10500  11.4  52.5  260   7  4   6.2   3.4 |  12.0  53.6  255   8  4   4.2   2.3
 10250  11.8  53.2  255   6  3   6.2   3.4 |  12.1  53.8  250   7  4   4.0   2.2
 10000  12.3  54.1  245   6  3   8.5   4.7 |  12.7  54.9  245   7  3   9.1   5.0
  9750  12.9  55.2  230   5  3   8.8   4.8 |  13.3  55.9  235   6  3   8.8   4.8
  9500  13.5  56.3  215   5  3   7.7   4.2 |  13.9  57.0  225   6  3   7.3   4.0
  9250  14.0  57.2  210   5  3   6.4   3.5 |  14.3  57.7  215   6  3   5.2   2.9
  9000  14.5  58.1  205   6  3   7.1   3.9 |  14.7  58.5  210   6  3   6.9   3.8
  8750  15.0  59.0  210   7  4   7.8   4.3 |  15.2  59.4  205   6  3   8.0   4.4
  8500  15.6  60.1  210   8  4   6.8   3.7 |  15.7  60.3  205   6  3   7.3   4.0
  8250  16.0  60.8  215   9  4   6.0   3.3 |  16.2  61.2  210   6  3   7.1   3.9
  8000  16.4  61.5  215   9  5   6.4   3.5 |  16.7  62.1  210   6  3   7.0   3.8
  7750  16.8  62.2  215  10  5   6.3   3.4 |  17.1  62.8  215   5  3   7.0   3.8
  7500  17.2  63.0  210  11  5   4.4   2.4 |  17.6  63.7  215   5  3   7.7   4.2
  7250  17.4  63.3  200  11  6   3.1   1.7 |  18.2  64.8  215   5  2   8.1   4.5
  7000  17.6  63.7  195  12  6   4.2   2.3 |  18.8  65.8  210   5  2   8.2   4.5
  6750  17.9  64.2  185  12  6   2.2   1.2 |  19.4  66.9  210   4  2   9.6   5.3
  6500  17.9  64.2  180  11  6  -1.3  -0.7 |  20.2  68.4  215   4  2  10.6   5.8
  6250  17.8  64.0  170  10  5  -1.4  -0.8 |  21.0  69.8  215   4  2  10.4   5.7
  6000  17.8  64.0  160   9  5  -2.1  -1.1 |  21.7  71.1  215   4  2  10.4   5.7
  5750  17.7  63.9  155   9  4   1.9   1.0 |  22.7  72.9  215   4  2  16.1   8.8
  5500  18.2  64.8  145   7  4  10.8   5.9 |  24.2  75.6  220   4  2  25.6  14.0
  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

           09/16/2014 at 1500 MDT          |       09/16/2014 at 1800 MDT
                                           |
K index... +17.5  LI... -2.6               | K index... +3.2  LI... -0.4
CAPE... +289.4  CIN... -40.5               | CAPE... 0.0  CIN... -0.2
                                           |
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 -66.8 -88.2  285  53 27   2.1   1.1 | -67.2 -89.0  285  55 28   2.1   1.2
 45000 -61.8 -79.2  280  66 34   6.7   3.7 | -61.9 -79.4  280  66 34   7.1   3.9
 40000 -51.6 -60.9  275  60 31   4.6   2.5 | -51.0 -59.8  275  60 31   5.2   2.9
 38000 -48.9 -56.0  270  44 23   4.6   2.5 | -47.9 -54.2  270  49 25   5.2   2.9
 36000 -46.1 -51.0  265  28 15   4.3   2.4 | -44.8 -48.6  270  38 20   5.1   2.8
 34000 -41.1 -42.0  265  25 13   8.9   4.9 | -40.3 -40.5  265  32 16   7.7   4.2
 32000 -35.8 -32.4  275  24 12   8.9   4.9 | -35.7 -32.3  260  26 13   7.6   4.2
 30000 -30.9 -23.6  270  24 12   8.0   4.4 | -30.9 -23.6  265  24 12   8.2   4.5
 29000 -27.8 -18.0  265  23 12   8.0   4.4 | -28.4 -19.1  270  24 12   8.2   4.5
 28000 -25.5 -13.9  265  23 12   7.3   4.0 | -25.4 -13.7  270  24 12   7.1   3.9
 27000 -23.3  -9.9  270  21 11   7.4   4.0 | -23.3  -9.9  275  22 11   7.2   4.0
 26000 -21.1  -6.0  275  20 10   7.4   4.1 | -21.1  -6.0  275  21 11   7.2   4.0
 25000 -18.8  -1.8  280  18  9   7.0   3.9 | -18.9  -2.0  280  20 10   7.1   3.9
 24000 -16.9   1.6  285  16  8   6.5   3.6 | -16.8   1.8  285  17  9   7.0   3.8
 23000 -14.9   5.2  290  13  7   6.5   3.6 | -14.7   5.5  295  14  7   7.0   3.8
 22000 -13.0   8.6  300  11  6   5.8   3.2 | -12.6   9.3  305  11  6   6.4   3.5
 21000 -11.5  11.3  305  10  5   5.1   2.8 | -10.9  12.4  310   9  5   5.7   3.1
 20000 -10.0  14.0  310   9  5   5.1   2.8 |  -9.2  15.4  320   7  4   5.7   3.1
 19500  -9.2  15.4  310   8  4   5.2   2.8 |  -8.4  16.9  325   7  3   5.7   3.1
 19000  -8.3  17.1  310   8  4   7.4   4.0 |  -7.4  18.7  330   6  3   7.0   3.8
 18500  -7.3  18.9  310   8  4   7.2   4.0 |  -6.4  20.5  335   6  3   6.9   3.8
 18000  -6.2  20.8  310   9  4   7.6   4.2 |  -5.4  22.3  340   6  3   7.4   4.1
 17500  -5.1  22.8  305   8  4   7.8   4.3 |  -4.2  24.4  340   6  3   7.9   4.3
 17000  -3.9  25.0  305   8  4   7.9   4.3 |  -3.0  26.6  340   6  3   7.9   4.3
 16500  -2.7  27.1  300   8  4   8.7   4.8 |  -1.8  28.8  340   7  3   8.3   4.6
 16000  -1.5  29.3  295   8  4   8.7   4.7 |  -0.6  30.9  340   7  4   8.3   4.5
 15500  -0.2  31.6  295   7  4   8.4   4.6 |   0.6  33.1  340   7  4   8.3   4.6
 15000   1.0  33.8  295   7  4   8.4   4.6 |   1.8  35.2  340   7  4   8.4   4.6
 14500   2.2  36.0  295   7  4   8.6   4.7 |   3.1  37.6  340   7  3   8.6   4.7
 14000   4.1  39.4  295   6  3   8.9   4.9 |   4.4  39.9  340   7  3   8.9   4.9
 13500   5.3  41.5  295   6  3   8.7   4.8 |   6.3  43.3  340   6  3   8.7   4.8
 13000   6.6  43.9  290   6  3   8.7   4.8 |   7.6  45.7  340   6  3   8.7   4.8
 12500   7.8  46.0  290   6  3   8.9   4.9 |   8.8  47.8  340   6  3   8.9   4.9
 12000   9.1  48.4  285   6  3   9.0   4.9 |  10.1  50.2  335   5  3   9.0   4.9
 11500  10.4  50.7  280   6  3   9.0   4.9 |  11.4  52.5  335   5  3   8.9   4.9
 11000  11.7  53.1  280   6  3   9.0   4.9 |  12.7  54.9  330   5  2   8.5   4.7
 10500  13.0  55.4  280   7  3   5.0   2.7 |  13.9  57.0  330   4  2   5.8   3.2
 10250  13.3  55.9  280   6  3   7.1   3.9 |  14.2  57.6  325   4  2   6.6   3.6
 10000  14.1  57.4  280   7  3  11.7   6.4 |  15.0  59.0  325   4  2  10.9   6.0
  9750  14.9  58.8  280   7  3  10.7   5.9 |  15.7  60.3  320   3  2  10.1   5.5
  9500  15.6  60.1  280   7  3   7.9   4.4 |  16.4  61.5  315   3  2   9.0   4.9
  9250  16.1  61.0  280   7  3   6.6   3.6 |  17.0  62.6  315   3  2   8.1   4.5
  9000  16.7  62.1  280   6  3   8.6   4.7 |  17.7  63.9  305   3  2   9.2   5.0
  8750  17.3  63.1  285   6  3   8.3   4.6 |  18.3  64.9  300   3  2   9.1   5.0
  8500  17.8  64.0  285   6  3   7.0   3.8 |  19.0  66.2  290   3  2   8.7   4.8
  8250  18.3  64.9  285   5  3   6.2   3.4 |  19.6  67.3  285   3  2   8.3   4.5
  8000  18.7  65.7  285   5  2   6.6   3.6 |  20.2  68.4  280   3  2   8.0   4.4
  7750  19.2  66.6  290   4  2   7.6   4.2 |  20.7  69.3  275   3  2   7.5   4.1
  7500  19.7  67.5  290   4  2   9.2   5.1 |  21.2  70.2  270   3  2   6.7   3.7
  7250  20.4  68.7  290   4  2   9.7   5.3 |  21.6  70.9  265   3  1   6.2   3.4
  7000  21.1  70.0  290   4  2   9.7   5.3 |  22.0  71.6  260   3  1   6.6   3.6
  6750  21.8  71.2  290   4  2  10.5   5.7 |  22.5  72.5  255   3  1   8.4   4.6
  6500  22.6  72.7  290   4  2  10.9   6.0 |  23.1  73.6  250   2  1  10.2   5.6
  6250  23.4  74.1  285   4  2  11.1   6.1 |  23.9  75.0  250   2  1  10.5   5.8
  6000  24.2  75.6  285   4  2  10.3   5.6 |  24.7  76.5  250   2  1  10.0   5.5
  5750  25.0  77.0  285   4  2  11.8   6.5 |  25.3  77.5  250   3  1   8.4   4.6
  5500  26.0  78.8  285   4  2  14.2   7.8 |  25.9  78.6  250   2  1   7.5   4.1
  5250  27.0  80.6  290   4  2  12.3   6.7 |  26.5  79.7  255   2  1   8.1   4.5
  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 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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