Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 300431
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
2231 MDT Friday, August 29, 2014

This forecast is for Saturday, August 30, 2014:

If the trigger temperature of 79.2 F/26.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1268 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18670 ft MSL (13646 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12906 ft MSL (7883 ft AGL)
Thermal soaring outlook for Sunday 08/31....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:41:02 / 19:49:02 MDT
Total possible sunshine........... 13 hr 8 min 0 sec (788 min 0 sec)
Altitude of sun at 13:14:37 MDT... 59.70 degrees

Upper air data from numerical model forecast valid on 08/30/2014 at 0600 MDT

Freezing level.................. 15187 ft MSL (10163 ft AGL)
Convective condensation level... 16746 ft MSL (11722 ft AGL)
Lifted condensation level....... 17272 ft MSL (12248 ft AGL)
Lifted index.................... -2.8
K index......................... +20.5

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  -63.5 -82.3   305   28   15   1.0   0.6      M     M       M      M    M
 45000  -60.6 -77.1   305   37   19   4.8   2.6      M     M       M      M    M
 40000  -53.0 -63.4   300   42   22   5.6   3.1      M     M       M      M    M
 38000  -49.6 -57.3   300   45   23   5.6   3.1      M     M       M      M    M
 36000  -46.3 -51.3   300   48   25   5.5   3.0      M     M       M      M    M
 34000  -41.7 -43.1   305   47   24   8.1   4.4      M     M       M      M    M
 32000  -36.8 -34.2   305   46   24   8.1   4.5      M     M       M      M    M
 30000  -32.2 -26.0   305   40   20   7.8   4.3   44.0 111.2     9.3      M    M
 29000  -29.9 -21.8   300   36   18   7.8   4.3   43.3 109.9     8.8      M    M
 28000  -27.5 -17.5   300   32   16   7.7   4.2   42.6 108.8     8.4      M    M
 27000  -25.3 -13.5   300   31   16   5.7   3.1   40.8 105.4     7.1      M    M
 26000  -23.6 -10.5   300   31   16   5.7   3.2   39.2 102.6     5.9      M    M
 25000  -21.9  -7.4   300   31   16   5.8   3.2   37.9 100.2     4.8      M    M
 24000  -20.0  -4.0   305   29   15   6.6   3.6   36.6  97.8     3.8      M    M
 23000  -18.1  -0.6   305   27   14   6.6   3.6   35.4  95.7     2.8      M    M
 22000  -16.2   2.8   310   25   13   6.9   3.8   34.3  93.8     1.9      M    M
 21000  -13.9   7.0   310   23   12   8.2   4.5   33.7  92.6     1.3      M    M
 20000  -11.5  11.3   310   21   11   8.3   4.5   33.1  91.6     0.8      M    M
 19500  -10.3  13.5   310   20   10   8.4   4.6   32.9  91.2     0.6      M    M
 19000   -9.1  15.6   310   19   10   7.3   4.0   32.6  90.7     0.3      M    M
 18500   -8.0  17.6   305   18    9   7.3   4.0   32.2  89.9    -0.1   1255  6.4
 18000   -7.0  19.4   300   17    9   7.0   3.9   31.8  89.2    -0.5   1208  6.1
 17500   -6.0  21.2   300   17    9   6.4   3.5   31.2  88.2    -1.0   1164  5.9
 17000   -5.0  23.0   300   16    8   6.1   3.3   30.6  87.2    -1.5   1120  5.7
 16500   -3.9  25.0   300   16    8   9.4   5.1   30.3  86.5    -1.8   1071  5.4
 16000   -2.5  27.5   300   16    8   9.3   5.1   30.2  86.4    -1.9   1014  5.2
 15500   -1.1  30.0   295   15    8   9.3   5.1   30.1  86.2    -1.9    958  4.9
 15000    0.3  32.5   295   15    8   9.3   5.1   30.0  86.1    -2.1    903  4.6
 14500    1.6  34.9   295   14    7   9.1   5.0   30.0  86.0    -2.2    848  4.3
 14000    2.8  37.0   290   13    7   8.4   4.6   29.8  85.6    -2.4    796  4.0
 13500    4.1  39.4   280   12    6   8.4   4.6   29.6  85.2    -2.7    744  3.8
 13000    5.9  42.6   270   12    6   8.4   4.6   29.2  84.6    -3.0    666  3.4
 12500    7.2  45.0   260   12    6   8.3   4.6   29.0  84.2    -3.2    614  3.1
 12000    8.4  47.1   250   10    5   8.2   4.5   28.8  83.8    -3.4    562  2.9
 11500    9.7  49.5   240    9    5   8.1   4.5   28.5  83.4    -3.7    510  2.6
 11000   10.9  51.6   230    9    5   7.8   4.3   28.2  82.8    -3.9    459  2.3
 10500   12.1  53.8   220    9    5   4.7   2.6   28.0  82.4    -4.2    408  2.1
 10250   12.3  54.1   215    9    5   5.4   3.0   27.5  81.4    -4.7    393  2.0
 10000   13.0  55.4   210    9    5  10.0   5.5   27.4  81.3    -4.8    366  1.9
  9750   13.7  56.7   210   10    5   9.0   5.0   27.3  81.2    -4.9    339  1.7
  9500   14.3  57.7   205   10    5   8.3   4.6   27.3  81.1    -4.9    311  1.6
  9250   14.9  58.8   200   11    5   7.2   3.9   27.1  80.8    -5.1    288  1.5
  9000   15.4  59.7   195   11    6   7.7   4.2   26.9  80.5    -5.3    264  1.3
  8750   16.0  60.8   195   12    6   8.0   4.4   26.8  80.2    -5.5    239  1.2
  8500   16.6  61.9   190   13    7   7.4   4.1   26.7  80.0    -5.6    214  1.1
  8250   17.1  62.8   185   13    7   6.9   3.8   26.4  79.6    -5.8    191  1.0
  8000   17.6  63.7   185   14    7   6.0   3.3   26.2  79.2    -6.1    169  0.9
  7750   18.0  64.4   180   14    7   5.2   2.9   25.9  78.6    -6.4    149  0.8
  7500   18.4  65.1   175   15    8   4.0   2.2   25.5  77.9    -6.8    131  0.7
  7250   18.5  65.3   175   14    7   2.7   1.5   25.0  77.0    -7.4    118  0.6
  7000   18.7  65.7   170   14    7   3.4   1.9   24.5  76.1    -7.9    106  0.5
  6750   18.9  66.0   165   14    7  -0.0  -0.0   23.9  75.0    -8.6     94  0.5
  6500   18.6  65.5   160   13    7  -5.7  -3.1   22.9  73.3    -9.6     95  0.5
  6250   17.9  64.2   155   12    6 -10.2  -5.6   21.6  70.9   -11.0    108  0.5
  6000   17.2  63.0   150   11    5  -0.3  -0.2   20.3  68.5   -12.4    120  0.6
  5750   17.3  63.1   130    9    5  -8.4  -4.6   19.7  67.4   -13.2    112  0.6
  5500   15.6  60.1   120    8    4 -27.0 -14.8   17.6  63.8   -15.3    156  0.8
  5250   13.9  57.0   110    7    3 -12.1  -6.6   15.6  60.2   -17.4    199  1.0
  5000      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/30/2014 at 0900 MDT          |       08/30/2014 at 1200 MDT
                                           |
K index... +25.1  LI... -0.3               | K index... +23.9  LI... -2.0
CAPE... +23.0  CIN... -92.3                | CAPE... +150.5  CIN... -87.3
                                           |
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 -64.3 -83.7  290  29 15   0.9   0.5 | -65.1 -85.2  285  39 20   1.3   0.7
 45000 -61.0 -77.8  295  37 19   6.0   3.3 | -61.3 -78.3  290  49 25   6.0   3.3
 40000 -51.8 -61.2  305  39 20   4.6   2.5 | -52.0 -61.6  285  43 22   5.5   3.0
 38000 -49.0 -56.2  300  47 24   4.5   2.5 | -48.7 -55.7  290  51 26   5.4   3.0
 36000 -46.3 -51.3  300  55 28   4.4   2.4 | -45.5 -49.9  295  59 30   5.3   2.9
 34000 -41.9 -43.4  300  54 28   8.1   4.4 | -41.2 -42.2  295  55 28   7.5   4.1
 32000 -37.1 -34.8  300  51 26   8.1   4.4 | -36.7 -34.1  295  49 25   7.6   4.1
 30000 -32.4 -26.3  300  43 22   7.8   4.3 | -31.9 -25.4  290  42 22   8.2   4.5
 29000 -30.1 -22.2  300  39 20   7.8   4.3 | -29.5 -21.1  290  38 20   8.2   4.5
 28000 -27.2 -17.0  295  33 17   6.9   3.8 | -26.5 -15.7  290  34 18   7.2   3.9
 27000 -25.3 -13.5  295  32 16   6.5   3.5 | -24.4 -11.9  285  33 17   6.9   3.8
 26000 -23.4 -10.1  290  31 16   6.5   3.6 | -22.4  -8.3  285  31 16   6.9   3.8
 25000 -21.5  -6.7  285  30 15   6.5   3.6 | -20.4  -4.7  280  29 15   6.7   3.7
 24000 -19.6  -3.3  285  27 14   6.2   3.4 | -18.9  -2.0  280  27 14   4.6   2.5
 23000 -17.8  -0.0  285  25 13   6.2   3.4 | -17.6   0.3  275  24 12   4.6   2.5
 22000 -15.9   3.4  285  22 11   6.6   3.6 | -16.2   2.8  275  21 11   5.5   3.0
 21000 -13.7   7.3  285  20 10   7.8   4.3 | -14.1   6.6  270  20 11   8.1   4.4
 20000 -11.4  11.5  285  19 10   7.8   4.3 | -11.6  11.1  270  20 10   8.1   4.5
 19500 -10.3  13.5  285  19 10   7.9   4.3 | -10.4  13.3  265  20 10   8.2   4.5
 19000  -9.2  15.4  285  18  9   7.3   4.0 |  -9.2  15.4  265  19 10   7.7   4.2
 18500  -8.1  17.4  290  18 10   7.3   4.0 |  -8.1  17.4  265  18  9   7.7   4.2
 18000  -7.1  19.2  290  19 10   7.6   4.2 |  -6.9  19.6  260  18  9   8.3   4.5
 17500  -5.9  21.4  290  18  9   8.2   4.5 |  -5.6  21.9  260  17  9   9.1   5.0
 17000  -4.7  23.5  285  18  9   8.1   4.5 |  -4.3  24.3  260  17  9   9.2   5.0
 16500  -3.5  25.7  285  17  9   8.6   4.7 |  -3.0  26.6  260  17  9   8.7   4.8
 16000  -2.2  28.0  280  17  9   8.5   4.7 |  -1.7  28.9  260  17  9   8.8   4.8
 15500  -0.9  30.4  275  16  8   8.4   4.6 |  -0.4  31.3  255  17  9   8.8   4.8
 15000   0.3  32.5  270  16  8   8.4   4.6 |   0.9  33.6  255  18  9   8.8   4.8
 14500   1.5  34.7  265  16  8   8.4   4.6 |   2.2  36.0  255  18  9   8.7   4.8
 14000   2.8  37.0  265  16  8   8.5   4.7 |   3.4  38.1  250  18  9   8.4   4.6
 13500   4.7  40.5  260  17  9   8.6   4.7 |   5.3  41.5  245  19 10   8.3   4.5
 13000   5.9  42.6  255  16  8   8.6   4.7 |   6.5  43.7  245  20 10   8.2   4.5
 12500   7.2  45.0  255  16  8   8.5   4.7 |   7.7  45.9  245  21 11   8.1   4.5
 12000   8.4  47.1  250  15  8   8.4   4.6 |   8.9  48.0  240  21 11   8.1   4.5
 11500   9.7  49.5  240  14  7   8.3   4.6 |  10.1  50.2  240  20 11   8.1   4.5
 11000  10.9  51.6  240  13  6   8.0   4.4 |  11.3  52.3  235  19 10   8.0   4.4
 10500  12.1  53.8  235  12  6   4.6   2.5 |  12.5  54.5  235  17  9   5.2   2.8
 10250  12.3  54.1  235  11  6   5.4   3.0 |  12.8  55.0  235  16  8   6.0   3.3
 10000  13.0  55.4  230  11  6  10.5   5.7 |  13.5  56.3  230  15  8  10.3   5.6
  9750  13.7  56.7  230  11  6   9.6   5.3 |  14.2  57.6  230  15  8   9.5   5.2
  9500  14.3  57.7  225  11  6   8.1   4.4 |  14.8  58.6  230  14  7   8.5   4.6
  9250  14.8  58.6  225  11  6   6.3   3.4 |  15.4  59.7  225  14  7   7.1   3.9
  9000  15.3  59.5  220  11  6   7.4   4.1 |  15.9  60.6  220  13  7   7.7   4.2
  8750  15.9  60.6  215  12  6   8.0   4.4 |  16.4  61.5  220  12  6   7.8   4.3
  8500  16.5  61.7  210  12  6   6.6   3.6 |  17.0  62.6  215  12  6   7.3   4.0
  8250  16.9  62.4  205  12  6   5.3   2.9 |  17.4  63.3  210  11  6   6.7   3.7
  8000  17.3  63.1  200  12  6   5.0   2.7 |  17.9  64.2  205  11  5   7.0   3.9
  7750  17.6  63.7  195  13  7   4.3   2.4 |  18.4  65.1  200  10  5   7.1   3.9
  7500  17.9  64.2  185  13  7   2.8   1.5 |  19.0  66.2  195  10  5   8.7   4.8
  7250  18.0  64.4  180  13  7   1.4   0.8 |  19.7  67.5  190  10  5  10.1   5.5
  7000  18.2  64.8  175  14  7   1.9   1.0 |  20.4  68.7  190   9  5   9.6   5.3
  6750  18.3  64.9  170  14  7   0.9   0.5 |  21.1  70.0  190   9  5   9.9   5.4
  6500  18.3  64.9  165  13  7  -0.8  -0.4 |  21.9  71.4  190   9  5  10.5   5.7
  6250  18.1  64.6  160  11  6  -0.2  -0.1 |  22.7  72.9  190   9  5  11.2   6.2
  6000  18.0  64.4  150   9  5  -3.6  -2.0 |  23.5  74.3  190   9  4   9.3   5.1
  5750  17.7  63.9  140   6  3   1.3   0.7 |  24.2  75.6  190   8  4  10.8   5.9
  5500  18.2  64.8  135   6  3  10.2   5.6 |  25.1  77.2  195   8  4  14.5   8.0
  5250  18.7  65.7  135   6  3   3.2   1.8 |  26.1  79.0  195   8  4  12.0   6.6
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/30/2014 at 1500 MDT          |       08/30/2014 at 1800 MDT
                                           |
K index... +28.3  LI... -2.1               | K index... +21.1  LI... -1.2
CAPE... +210.5  CIN... -26.5               | CAPE... +51.4  CIN... -74.1
                                           |
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 -64.7 -84.5  280  41 21   0.9   0.5 | -63.7 -82.7  280  44 23   0.9   0.5
 45000 -61.3 -78.3  285  54 28   5.9   3.3 | -60.9 -77.6  280  60 31   4.7   2.6
 40000 -52.1 -61.8  280  59 31   5.0   2.7 | -53.2 -63.8  275  65 34   6.0   3.3
 38000 -49.2 -56.6  280  62 32   4.9   2.7 | -49.6 -57.3  275  57 30   6.0   3.3
 36000 -46.2 -51.2  280  65 34   4.7   2.6 | -46.0 -50.8  270  50 26   5.9   3.3
 34000 -41.5 -42.7  280  57 29   8.4   4.6 | -41.4 -42.5  270  46 24   8.1   4.4
 32000 -36.5 -33.7  275  47 24   8.3   4.5 | -36.5 -33.7  270  44 23   8.2   4.5
 30000 -31.6 -24.9  275  42 22   8.2   4.5 | -31.6 -24.9  270  45 23   8.3   4.6
 29000 -29.2 -20.6  270  41 21   8.2   4.5 | -29.1 -20.4  270  46 24   8.4   4.6
 28000 -26.7 -16.1  270  40 21   8.0   4.4 | -26.6 -15.9  270  47 24   8.3   4.6
 27000 -24.1 -11.4  270  38 20   6.9   3.8 | -24.0 -11.2  265  48 25   6.8   3.7
 26000 -22.1  -7.8  270  36 19   6.9   3.8 | -22.0  -7.6  265  50 25   6.8   3.7
 25000 -20.0  -4.0  265  35 18   6.9   3.8 | -20.0  -4.0  265  51 26   6.9   3.8
 24000 -18.1  -0.6  265  34 17   6.4   3.5 | -18.4  -1.1  260  49 25   5.3   2.9
 23000 -16.3   2.7  265  34 17   6.4   3.5 | -16.8   1.8  255  46 24   5.3   2.9
 22000 -14.4   6.1  265  33 17   6.5   3.6 | -15.2   4.6  250  45 23   5.5   3.0
 21000 -12.4   9.7  255  32 16   6.7   3.7 | -13.3   8.1  245  41 21   6.9   3.8
 20000 -10.4  13.3  250  31 16   6.7   3.7 | -11.2  11.8  245  38 20   6.9   3.8
 19500  -9.4  15.1  245  30 16   6.7   3.7 | -10.2  13.6  245  36 19   6.8   3.7
 19000  -8.5  16.7  245  30 15   6.9   3.8 |  -9.1  15.6  240  35 18   8.3   4.5
 18500  -7.5  18.5  245  28 15   7.0   3.8 |  -7.9  17.8  240  34 18   8.4   4.6
 18000  -6.5  20.3  240  27 14   7.2   3.9 |  -6.7  19.9  240  34 17   8.7   4.8
 17500  -5.4  22.3  240  27 14   7.6   4.2 |  -5.3  22.5  240  33 17   9.6   5.3
 17000  -4.3  24.3  240  27 14   7.6   4.1 |  -3.9  25.0  240  32 17   9.6   5.3
 16500  -3.1  26.4  240  26 14   8.0   4.4 |  -2.5  27.5  240  32 16   9.2   5.0
 16000  -2.0  28.4  240  26 14   8.0   4.4 |  -1.2  29.8  240  31 16   9.1   5.0
 15500  -0.8  30.6  240  26 13   8.6   4.7 |   0.2  32.4  240  30 16   9.1   5.0
 15000   0.5  32.9  235  26 13   9.1   5.0 |   1.5  34.7  240  30 15   9.1   5.0
 14500   1.8  35.2  235  25 13   9.3   5.1 |   2.9  37.2  245  29 15   9.2   5.0
 14000   3.3  37.9  235  25 13   9.9   5.4 |   4.3  39.7  245  29 15   9.5   5.2
 13500   4.7  40.5  235  24 12   9.9   5.4 |   5.7  42.3  245  28 14   9.5   5.2
 13000   6.9  44.4  235  23 12   9.8   5.4 |   7.7  45.9  245  27 14   9.2   5.0
 12500   8.4  47.1  235  22 12   9.5   5.2 |   9.1  48.4  250  26 13   9.2   5.0
 12000   9.7  49.5  235  21 11   9.2   5.0 |  10.5  50.9  250  25 13   9.1   5.0
 11500  11.1  52.0  235  20 11   8.6   4.7 |  11.8  53.2  250  24 12   9.0   4.9
 11000  12.2  54.0  235  19 10   7.3   4.0 |  13.0  55.4  250  23 12   7.9   4.3
 10500  13.3  55.9  235  18  9  11.0   6.0 |  14.2  57.6  255  21 11  10.6   5.8
 10250  14.2  57.6  235  16  8  11.7   6.4 |  15.1  59.2  255  21 11  10.9   6.0
 10000  14.8  58.6  235  15  8   7.1   3.9 |  15.7  60.3  255  20 10   7.6   4.2
  9750  15.4  59.7  235  14  7   8.7   4.8 |  16.3  61.3  255  19 10   8.6   4.7
  9500  16.0  60.8  235  13  7   7.0   3.8 |  16.9  62.4  255  18  9   8.2   4.5
  9250  16.5  61.7  240  11  6   7.2   3.9 |  17.5  63.5  255  17  9   7.9   4.3
  9000  17.1  62.8  240  10  5   8.9   4.9 |  18.1  64.6  260  16  8   7.7   4.2
  8750  17.7  63.9  245   9  5   8.3   4.6 |  18.7  65.7  260  15  8   7.7   4.2
  8500  18.3  64.9  245   8  4   9.6   5.3 |  19.2  66.6  260  14  7   8.0   4.4
  8250  19.1  66.4  250   8  4  10.9   6.0 |  19.8  67.6  260  12  6   8.6   4.7
  8000  19.8  67.6  250   8  4   9.8   5.4 |  20.4  68.7  265  11  5   8.0   4.4
  7750  20.5  68.9  250   8  4   8.9   4.9 |  21.0  69.8  270   9  5   7.3   4.0
  7500  21.2  70.2  250   8  4   9.7   5.3 |  21.5  70.7  275   8  4   8.1   4.4
  7250  22.0  71.6  250   8  4  10.4   5.7 |  22.1  71.8  275   7  4   9.1   5.0
  7000  22.7  72.9  250   8  4   9.9   5.4 |  22.8  73.0  280   7  4   8.9   4.9
  6750  23.5  74.3  255   7  4   9.5   5.2 |  23.4  74.1  280   7  3   8.3   4.6
  6500  24.2  75.6  255   7  4  10.4   5.7 |  24.1  75.4  280   6  3   9.6   5.3
  6250  25.0  77.0  255   7  4  11.3   6.2 |  24.9  76.8  280   6  3  10.9   6.0
  6000  25.8  78.4  255   7  4  10.1   5.5 |  25.6  78.1  285   6  3  10.0   5.5
  5750  26.5  79.7  255   7  4  10.7   5.8 |  26.3  79.3  285   6  3   8.2   4.5
  5500  27.4  81.3  255   7  4  13.5   7.4 |  26.9  80.4  285   5  3   6.9   3.8
  5250  28.4  83.1  255   7  4  13.7   7.5 |  27.3  81.1  285   5  3   7.0   3.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613



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