Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Wednesday, September 21, 2016

This forecast is for Wednesday, September 21, 2016:

If the trigger temperature of 70.2 F/21.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 455 ft/min (2.3 m/s)
   Maximum height of thermals.................. 12062 ft MSL (7223 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1245 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9103 ft MSL (4264 ft AGL)
Thermal soaring outlook for Thursday 09/22..... Good

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

Remarks...

Sunrise/Sunset.................... 07:01:24 / 19:13:25 MDT
Total possible sunshine........... 12 hr 12 min 0 sec (732 min 0 sec)
Altitude of sun at 13:06:55 MDT... 51.20 degrees

Upper air data from rawinsonde observation taken on 09/21/2016 at 0600 MDT

Freezing level.................. 13468 ft MSL (8629 ft AGL)
Convective condensation level... 13332 ft MSL (8493 ft AGL)
Lifted condensation level....... 12883 ft MSL (8043 ft AGL)
Lifted index.................... +3.9
K index......................... +22.5

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  -65.0 -85.0   270   30   15   1.3   0.7   87.2 189.0    36.3      M    M
 45000  -60.6 -77.1   255   57   29   4.4   2.4   69.0 156.1    27.7      M    M
 40000  -54.1 -65.4   250   48   25   4.8   2.6   56.4 133.5    21.3      M    M
 38000  -49.6 -57.3   245   42   22   7.7   4.3   54.4 129.9    20.4      M    M
 36000  -45.8 -50.4   235   36   19   6.5   3.6   51.4 124.6    18.9      M    M
 34000  -40.6 -41.1   235   37   19   9.5   5.2   50.5 122.9    18.7      M    M
 32000  -34.6 -30.3   240   39   20   9.0   4.9   49.8 121.6    18.7      M    M
 30000  -29.5 -21.1   240   39   20   8.6   4.7   48.9 120.0    18.4      M    M
 29000  -27.2 -17.0   240   38   20   9.4   5.2   48.0 118.5    18.0      M    M
 28000  -24.7 -12.5   240   37   19   8.1   4.4   47.5 117.5    17.7      M    M
 27000  -22.3  -8.1   245   37   19   8.0   4.4   46.9 116.4    17.4      M    M
 26000  -20.3  -4.5   245   36   18  -0.7  -0.4   45.8 114.5    16.8      M    M
 25000  -19.0  -2.2   245   35   18   8.3   4.6   43.9 111.0    15.4      M    M
 24000  -16.3   2.7   250   38   20   6.2   3.4   43.6 110.6    15.3      M    M
 23000  -15.0   5.0   250   36   18   8.2   4.5   41.6 106.9    13.9      M    M
 22000  -12.8   9.0   250   34   17   4.4   2.4   40.8 105.5    13.3      M    M
 21000  -11.9  10.6   245   31   16   3.6   2.0   38.5 101.3    11.4      M    M
 20000   -9.7  14.5   245   29   15   7.2   3.9   37.6  99.8    10.8      M    M
 19500   -9.0  15.8   250   30   16   4.1   2.3   36.8  98.2    10.1      M    M
 19000   -8.4  16.9   250   32   16   6.2   3.4   35.9  96.6     9.3      M    M
 18500   -7.4  18.7   250   31   16   6.3   3.5   35.4  95.6     8.8      M    M
 18000   -6.5  20.3   250   30   16   6.5   3.6   34.8  94.6     8.3      M    M
 17500   -5.5  22.1   250   30   15   6.5   3.6   34.2  93.6     7.9      M    M
 17000   -4.3  24.3   250   28   15   4.8   2.6   33.2  91.8     7.0      M    M
 16500   -3.5  25.7   250   28   14   5.0   2.7   32.4  90.4     6.3      M    M
 16000   -2.8  27.0   250   27   14   5.0   2.7   31.6  89.0     5.6      M    M
 15500   -2.1  28.2   240   27   14   5.0   2.7   30.8  87.5     4.9      M    M
 15000   -1.4  29.5   235   27   14   5.0   2.8   30.0  86.0     4.1      M    M
 14500   -0.7  30.7   225   28   14   5.5   3.0   29.2  84.6     3.4      M    M
 14000   -0.3  31.5   220   29   15  -2.8  -1.6   28.1  82.6     2.4      M    M
 13500    0.1  32.2   220   25   13   8.4   4.6   26.9  80.3     1.3      M    M
 13000    1.1  34.0   220   22   11   7.2   4.0   26.4  79.5     0.9      M    M
 12500    2.1  35.8   220   19   10   7.3   4.0   26.0  78.8     0.5      M    M
 12000    2.9  37.2   220   16    8  -2.1  -1.2   25.3  77.5    -0.2    550  2.8
 11500    3.1  37.6   225   15    8   7.9   4.3   23.8  74.9    -1.5    531  2.7
 11000    4.1  39.4   235   14    7   7.1   3.9   23.4  74.1    -1.9    485  2.5
 10500    5.1  41.2   245   14    7   7.3   4.0   23.0  73.3    -2.4    439  2.2
 10250    5.7  42.3   245   13    7   8.2   4.5   22.8  73.1    -2.5    414  2.1
 10000    6.3  43.3   240   12    6   8.5   4.7   22.7  72.9    -2.6    388  2.0
  9750    6.9  44.4   240   11    6   8.4   4.6   22.6  72.7    -2.7    362  1.8
  9500    7.6  45.7   240   10    5   8.5   4.6   22.5  72.5    -2.8    336  1.7
  9250    8.2  46.8   235    9    5   8.5   4.6   22.4  72.4    -2.9    310  1.6
  9000    8.8  47.8   230    8    4   8.5   4.6   22.4  72.2    -3.0    284  1.4
  8750    9.4  48.9   220    9    4   8.5   4.6   22.3  72.1    -3.2    258  1.3
  8500   10.1  50.2   210    9    5   8.5   4.6   22.1  71.9    -3.3    232  1.2
  8250   10.7  51.3   200   11    5   8.5   4.6   22.1  71.7    -3.4    206  1.0
  8000   11.3  52.3   195   12    6   8.5   4.6   22.0  71.5    -3.5    180  0.9
  7750   11.9  53.4   185   13    7   8.5   4.7   21.9  71.3    -3.6    154  0.8
  7500   12.5  54.5   180   15    8   8.4   4.6   21.7  71.1    -3.7    128  0.6
  7250   13.2  55.8   175   17    9   8.7   4.8   21.6  71.0    -3.9    102  0.5
  7000   13.8  56.8   170   20   10   7.6   4.2   21.5  70.8    -4.0     76  0.4
  6750   14.1  57.4   170   20   10  -0.1  -0.0   21.1  70.1    -4.4     58  0.3
  6500   13.9  57.0   170   19   10  -1.8  -1.0   20.2  68.3    -5.3     58  0.3
  6250   14.0  57.2   165   19   10   5.1   2.8   19.6  67.3    -5.9     46  0.2
  6000   14.5  58.1   165   18    9   6.8   3.7   19.4  66.9    -6.2     25  0.1
  5750   14.9  58.8   160   16    8   6.3   3.5   19.1  66.4    -6.5      4  0.0
  5500   15.4  59.7   145   13    7   6.5   3.6   18.9  65.9    -6.8      M    M
  5250   15.9  60.6   130   11    6   6.3   3.4   18.6  65.5    -7.1      M    M
  5000   16.3  61.3   110   11    6   7.1   3.9   18.4  65.1    -7.4      M    M

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

           09/21/2016 at 0900 MDT          |       09/21/2016 at 1200 MDT
                                           |
K index... +28.2  LI... +273.6             | K index... +30.2  LI... +272.7
CAPE... 0.0  CIN... M                      | CAPE... +0.5  CIN... -0.3
                                           |
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 -65.5 -85.9  255  43 22   3.2   1.8 | -65.2 -85.4  250  44 23   2.9   1.6
 45000 -59.6 -75.3  255  52 27   4.9   2.7 | -59.9 -75.8  255  53 27   4.6   2.5
 40000 -52.1 -61.8  250  49 25   6.0   3.3 | -52.6 -62.7  260  51 26   6.6   3.6
 38000 -48.5 -55.3  250  47 24   6.0   3.3 | -48.6 -55.5  255  46 23   6.6   3.6
 36000 -44.9 -48.8  245  46 24   5.9   3.3 | -44.6 -48.3  250  41 21   6.5   3.6
 34000 -40.4 -40.7  240  45 23   7.9   4.3 | -39.8 -39.6  250  39 20   8.3   4.6
 32000 -35.1 -31.2  235  44 23   7.7   4.2 | -34.9 -30.8  250  38 19   8.3   4.5
 30000 -30.4 -22.7  240  41 21   8.0   4.4 | -29.9 -21.8  240  37 19   7.1   3.9
 29000 -28.0 -18.4  245  39 20   8.0   4.4 | -27.8 -18.0  240  37 19   7.2   3.9
 28000 -25.7 -14.3  245  37 19   7.6   4.2 | -25.6 -14.1  235  37 19   7.2   3.9
 27000 -23.5 -10.3  250  36 19   7.3   4.0 | -23.5 -10.3  235  35 18   7.2   4.0
 26000 -21.4  -6.5  255  36 18   7.3   4.0 | -21.4  -6.5  235  33 17   7.3   4.0
 25000 -19.2  -2.6  255  35 18   7.4   4.1 | -19.3  -2.7  235  31 16   7.4   4.0
 24000 -17.2   1.0  255  35 18   6.7   3.7 | -17.2   1.0  240  32 16   7.1   3.9
 23000 -15.2   4.6  255  35 18   6.8   3.7 | -15.1   4.8  245  33 17   7.1   3.9
 22000 -13.3   8.1  250  34 18   6.8   3.8 | -13.0   8.6  245  34 18   7.1   3.9
 21000 -11.4  11.5  250  34 17   6.2   3.4 | -11.2  11.8  250  36 18   6.2   3.4
 20000  -9.7  14.5  250  33 17   6.2   3.4 |  -9.4  15.1  250  37 19   6.2   3.4
 19500  -8.8  16.2  250  33 17   6.2   3.4 |  -8.5  16.7  250  37 19   6.2   3.4
 19000  -7.9  17.8  250  33 17   6.3   3.5 |  -7.6  18.3  250  38 19   6.4   3.5
 18500  -7.0  19.4  250  33 17   6.4   3.5 |  -6.7  19.9  250  38 20   6.4   3.5
 18000  -5.6  21.9  255  34 17   6.3   3.5 |  -5.8  21.6  250  39 20   6.4   3.5
 17500  -4.7  23.5  255  34 17   6.3   3.5 |  -4.8  23.4  250  39 20   6.5   3.5
 17000  -3.8  25.2  255  34 17   6.3   3.5 |  -3.9  25.0  250  39 20   6.5   3.6
 16500  -2.9  26.8  255  34 17   5.9   3.2 |  -3.0  26.6  250  39 20   5.8   3.2
 16000  -2.1  28.2  250  33 17   6.0   3.3 |  -2.2  28.0  250  38 19   5.8   3.2
 15500  -1.3  29.7  250  33 17   4.8   2.6 |  -1.4  29.5  245  37 19   5.7   3.1
 15000  -0.6  30.9  250  32 16   4.6   2.5 |  -0.6  30.9  245  36 18   5.7   3.1
 14500   0.0  32.0  250  31 16   5.0   2.8 |   0.2  32.4  245  34 18   5.7   3.2
 14000   0.8  33.4  250  29 15   5.4   3.0 |   1.5  34.7  240  31 16   6.0   3.3
 13500   1.6  34.9  245  26 14   5.8   3.2 |   2.4  36.3  240  29 15   5.7   3.1
 13000   2.6  36.7  245  25 13   6.7   3.7 |   3.1  37.6  240  27 14   5.3   2.9
 12500   3.5  38.3  245  23 12   6.4   3.5 |   3.9  39.0  235  25 13   5.2   2.8
 12000   4.2  39.6  240  21 11   4.1   2.2 |   4.5  40.1  230  23 12   4.8   2.6
 11500   4.8  40.6  235  20 10   4.3   2.4 |   5.2  41.4  230  20 11   5.0   2.7
 11000   5.5  41.9  235  18  9   5.9   3.2 |   6.0  42.8  225  18  9   5.5   3.0
 10500   6.3  43.3  230  15  8   5.1   2.8 |   6.8  44.2  220  16  8   3.1   1.7
 10250   6.6  43.9  230  14  7   2.2   1.2 |   6.9  44.4  220  15  8   3.1   1.7
 10000   6.7  44.1  230  12  6   3.2   1.7 |   7.3  45.1  215  14  7   6.4   3.5
  9750   7.0  44.6  225  11  6   5.2   2.9 |   7.7  45.9  215  13  7   6.0   3.3
  9500   7.3  45.1  220   9  5   4.5   2.5 |   8.1  46.6  210  12  6   5.2   2.8
  9250   7.6  45.7  220   8  4   3.5   1.9 |   8.4  47.1  210  11  6   3.9   2.1
  9000   7.9  46.2  215   7  4   4.2   2.3 |   8.7  47.7  205  10  5   4.8   2.6
  8750   8.2  46.8  210   6  3   5.4   3.0 |   9.1  48.4  200   9  5   5.3   2.9
  8500   8.6  47.5  205   5  3   5.5   3.0 |   9.5  49.1  195   7  4   5.3   2.9
  8250   9.1  48.4  205   5  3   6.0   3.3 |   9.9  49.8  195   6  3   5.3   2.9
  8000   9.5  49.1  200   5  2   6.1   3.4 |  10.3  50.5  195   5  3   5.8   3.2
  7750  10.0  50.0  200   4  2   6.4   3.5 |  10.7  51.3  195   4  2   6.8   3.8
  7500  10.5  50.9  195   5  2   6.6   3.6 |  11.3  52.3  200   3  2   8.5   4.7
  7250  11.0  51.8  185   5  3   6.7   3.7 |  12.0  53.6  205   3  2   9.6   5.3
  7000  11.4  52.5  180   6  3   6.7   3.7 |  12.7  54.9  210   3  2   9.3   5.1
  6750  11.9  53.4  175   7  4   6.7   3.7 |  13.4  56.1  215   3  2  10.1   5.5
  6500  12.4  54.3  170   7  4   6.7   3.7 |  14.2  57.6  220   3  1  10.7   5.9
  6250  13.0  55.4  170   6  3   7.3   4.0 |  15.0  59.0  230   3  1  11.0   6.0
  6000  13.5  56.3  165   6  3   5.5   3.0 |  15.8  60.4  235   3  1   9.9   5.4
  5750  13.9  57.0  155   5  2   8.8   4.8 |  16.5  61.7  240   3  1  11.2   6.1
  5500  15.0  59.0  155   4  2  19.5  10.7 |  17.5  63.5  240   3  1  13.6   7.5
  5250     M     M    M   M  M     M     M |  18.4  65.1  240   3  1  11.7   6.4
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/21/2016 at 1500 MDT          |       09/21/2016 at 1800 MDT
                                           |
K index... +28.9  LI... +272.5             | K index... +28.2  LI... +271.6
CAPE... +55.2  CIN... -31.7                | CAPE... +276.0  CIN... -17.5
                                           |
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 -65.6 -86.1  250  42 22   2.8   1.5 | -65.5 -85.9  245  41 21   2.5   1.4
 45000 -60.3 -76.5  255  53 27   4.7   2.6 | -60.8 -77.4  250  52 27   4.8   2.7
 40000 -52.8 -63.0  260  52 27   6.7   3.7 | -52.8 -63.0  255  54 28   7.0   3.8
 38000 -48.7 -55.7  255  47 24   6.8   3.7 | -48.6 -55.5  250  50 26   7.1   3.9
 36000 -44.7 -48.5  245  42 22   6.7   3.7 | -44.4 -47.9  245  47 24   7.0   3.8
 34000 -40.0 -40.0  240  41 21   7.9   4.3 | -39.8 -39.6  245  46 24   7.8   4.3
 32000 -35.3 -31.5  240  40 20   7.8   4.3 | -35.1 -31.2  245  46 24   7.7   4.2
 30000 -30.2 -22.4  245  36 19   8.6   4.7 | -30.3 -22.5  245  41 21   8.2   4.5
 29000 -27.0 -16.6  245  34 17   8.6   4.7 | -27.3 -17.1  240  37 19   8.2   4.5
 28000 -24.5 -12.1  245  32 16   7.5   4.1 | -24.9 -12.8  235  35 18   7.6   4.2
 27000 -22.3  -8.1  240  34 17   7.3   4.0 | -22.7  -8.9  235  35 18   7.4   4.1
 26000 -20.2  -4.4  235  36 18   7.4   4.1 | -20.5  -4.9  240  35 18   7.4   4.1
 25000 -18.1  -0.6  230  38 19   7.5   4.1 | -18.3  -0.9  240  35 18   7.4   4.1
 24000 -16.2   2.8  235  36 19   6.2   3.4 | -16.3   2.7  240  35 18   6.8   3.7
 23000 -14.4   6.1  235  34 17   6.2   3.4 | -14.3   6.3  240  35 18   6.8   3.7
 22000 -12.5   9.5  240  31 16   6.3   3.5 | -12.3   9.9  240  36 18   6.8   3.7
 21000 -10.6  12.9  240  31 16   6.8   3.7 | -10.4  13.3  240  36 19   6.5   3.6
 20000  -8.6  16.5  245  31 16   6.8   3.7 |  -8.5  16.7  240  37 19   6.6   3.6
 19500  -7.6  18.3  245  31 16   6.8   3.7 |  -7.6  18.3  240  37 19   6.6   3.6
 19000  -6.7  19.9  245  31 16   6.3   3.4 |  -6.6  20.1  240  37 19   6.0   3.3
 18500  -5.8  21.6  245  31 16   6.2   3.4 |  -5.8  21.6  240  36 19   5.8   3.2
 18000  -4.9  23.2  245  31 16   6.0   3.3 |  -4.9  23.2  240  35 18   5.8   3.2
 17500  -4.1  24.6  250  31 16   4.9   2.7 |  -4.1  24.6  240  35 18   5.4   2.9
 17000  -3.4  25.9  250  32 16   5.0   2.7 |  -3.3  26.1  240  34 17   5.4   3.0
 16500  -2.7  27.1  250  32 16   5.6   3.1 |  -2.5  27.5  240  33 17   5.5   3.0
 16000  -1.8  28.8  250  32 16   5.7   3.1 |  -1.7  28.9  240  32 17   5.6   3.1
 15500  -1.0  30.2  250  32 16   5.7   3.1 |  -0.9  30.4  240  32 16   5.8   3.2
 15000  -0.2  31.6  250  31 16   5.7   3.1 |  -0.0  32.0  240  31 16   6.1   3.3
 14500   0.6  33.1  245  31 16   5.7   3.1 |   0.8  33.4  240  31 16   6.1   3.3
 14000   1.8  35.2  245  31 16   5.8   3.2 |   2.2  36.0  240  29 15   6.7   3.7
 13500   2.7  36.9  245  31 16   6.2   3.4 |   3.2  37.8  240  28 14   6.7   3.7
 13000   3.6  38.5  245  30 16   6.6   3.6 |   4.1  39.4  235  26 13   6.8   3.7
 12500   4.5  40.1  245  30 15   6.9   3.8 |   5.0  41.0  230  24 12   7.0   3.8
 12000   5.6  42.1  240  29 15   7.6   4.1 |   6.1  43.0  225  21 11   7.8   4.3
 11500   6.6  43.9  240  27 14   7.3   4.0 |   7.1  44.8  220  19 10   7.9   4.3
 11000   7.6  45.7  235  24 12   6.0   3.3 |   8.2  46.8  215  17  9   8.0   4.4
 10500   8.4  47.1  225  21 11   3.6   2.0 |   9.4  48.9  210  15  8   5.4   2.9
 10250   8.6  47.5  225  20 10   4.7   2.6 |   9.7  49.5  205  14  7   6.6   3.6
 10000   9.2  48.6  220  18  9   8.6   4.7 |  10.4  50.7  205  14  7  11.0   6.0
  9750   9.7  49.5  215  16  8   8.0   4.4 |  11.1  52.0  200  13  7  10.1   5.5
  9500  10.2  50.4  215  14  7   6.6   3.6 |  11.9  53.4  200  13  7   9.4   5.1
  9250  10.6  51.1  210  13  7   4.2   2.3 |  12.5  54.5  195  12  6   7.3   4.0
  9000  10.9  51.6  205  11  6   5.3   2.9 |  13.0  55.4  195  12  6   7.4   4.0
  8750  11.3  52.3  200   9  5   6.2   3.4 |  13.5  56.3  190  11  6   8.1   4.5
  8500  11.7  53.1  195   8  4   5.7   3.1 |  14.1  57.4  190  10  5   7.0   3.8
  8250  12.1  53.8  190   6  3   5.1   2.8 |  14.5  58.1  185   8  4   5.1   2.8
  8000  12.5  54.5  185   4  2   6.3   3.5 |  14.9  58.8  180   7  3   4.9   2.7
  7750  13.0  55.4  170   3  1   7.4   4.1 |  15.2  59.4  170   4  2   4.2   2.3
  7500  13.6  56.5  145   1  1   8.1   4.4 |  15.5  59.9  145   3  1   6.7   3.7
  7250  14.3  57.7  135   1  0   8.7   4.8 |  16.2  61.2  145   2  1   9.4   5.1
  7000  14.9  58.8  110   1  0   9.2   5.0 |  16.8  62.2  145   2  1   8.8   4.9
  6750  15.6  60.1  060   1  0  10.5   5.8 |  17.5  63.5  140   1  1   9.3   5.1
  6500  16.4  61.5  030   1  0  10.7   5.9 |  18.2  64.8  135   1  0  10.2   5.6
  6250  17.2  63.0  010   1  0  11.2   6.1 |  19.0  66.2  135   1  0  11.0   6.0
  6000  18.0  64.4  360   1  1   9.6   5.3 |  19.8  67.6  140   1  0  10.0   5.5
  5750  18.7  65.7  355   1  1  11.2   6.1 |  20.5  68.9  000   0  0   8.6   4.7
  5500  19.7  67.5  350   1  1  14.6   8.0 |  21.1  70.0  000   0  0   8.4   4.6
  5250  20.8  69.4  350   2  1  11.9   6.5 |  21.8  71.2  000   0  0   8.8   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 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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