Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 311232
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0631 MDT Monday, August 31, 2015

This forecast is for Monday, August 31, 2015:

If the trigger temperature of 78.6 F/25.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 514 ft/min (2.6 m/s)
   Maximum height of thermals.................. 13727 ft MSL (8888 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1245 MDT
Time of overdevelopment........................ 0700 MDT
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................. 11690 ft MSL (6851 ft AGL)
Thermal soaring outlook for Tuesday 09/01...... Fair

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

Remarks...

Sunrise/Sunset.................... 06:41:43 / 19:47:53 MDT
Total possible sunshine........... 13 hr 6 min 10 sec (786 min 10 sec)
Altitude of sun at 13:14:22 MDT... 59.42 degrees

Upper air data from rawinsonde observation taken on 08/31/2015 at 0600 MDT

Freezing level.................. 15227 ft MSL (10388 ft AGL)
Convective condensation level... 13211 ft MSL (8372 ft AGL)
Lifted condensation level....... 13423 ft MSL (8584 ft AGL)
Lifted index.................... -4.5
K index......................... +26.6

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  -64.1 -83.4   240   30   16   6.2   3.4   88.8 191.9    33.7      M    M
 45000  -62.9 -81.2   240   62   32  -0.2  -0.1   65.3 149.6    21.6      M    M
 40000  -54.6 -66.3   230   52   27   8.1   4.5   55.2 131.4    16.4      M    M
 38000  -49.7 -57.5   225   50   26   8.4   4.6   53.9 129.1    16.0      M    M
 36000  -45.2 -49.4   220   47   24   8.0   4.4   52.1 125.7    15.1      M    M
 34000  -40.1 -40.2   225   45   23   8.7   4.7   51.0 123.8    14.7      M    M
 32000  -34.5 -30.1   235   42   22   6.8   3.7   49.7 121.4    14.1      M    M
 30000  -29.7 -21.5   230   38   19   8.4   4.6   48.3 119.0    13.4      M    M
 29000  -27.2 -17.0   235   36   19   8.2   4.5   47.8 118.0    13.2      M    M
 28000  -24.9 -12.8   235   34   18   6.1   3.3   46.9 116.5    12.6      M    M
 27000  -22.9  -9.2   240   33   17   8.3   4.5   45.7 114.3    11.8      M    M
 26000  -21.1  -6.0   240   31   16   6.3   3.5   44.2 111.6    10.8      M    M
 25000  -19.0  -2.2   245   30   15   7.4   4.1   43.3 109.9    10.2      M    M
 24000  -16.6   2.1   245   28   15   8.6   4.7   42.6 108.6     9.8      M    M
 23000  -16.0   3.2   245   26   13  -5.7  -3.1   39.7 103.5     7.5      M    M
 22000  -15.1   4.8   245   24   12  15.0   8.2   37.6  99.7     5.6      M    M
 21000  -12.3   9.9   240   21   11   6.2   3.4   37.5  99.5     5.4      M    M
 20000  -10.6  12.9   240   19   10   6.0   3.3   36.2  97.2     4.3      M    M
 19500   -9.7  14.5   245   17    9   5.9   3.3   35.5  96.0     3.7      M    M
 19000   -8.8  16.2   255   15    7   6.7   3.7   34.9  94.8     3.2      M    M
 18500   -7.8  18.0   265   13    7   6.8   3.7   34.3  93.8     2.7      M    M
 18000   -6.8  19.8   270   12    6   6.8   3.7   33.8  92.9     2.2      M    M
 17500   -5.4  22.3   285   11    6   6.8   3.7   33.1  91.6     1.6      M    M
 17000   -4.3  24.3   295   11    5   7.8   4.3   32.7  90.8     1.2      M    M
 16500   -3.1  26.4   305   11    6   8.3   4.6   32.4  90.4     1.0      M    M
 16000   -1.8  28.8   315   11    6   8.3   4.6   32.2  90.0     0.8      M    M
 15500   -0.5  31.1   310   11    6   8.2   4.5   32.0  89.6     0.7      M    M
 15000    0.8  33.4   305   11    6   9.6   5.3   31.8  89.3     0.5      M    M
 14500    2.1  35.8   300   11    6   9.3   5.1   31.8  89.2     0.3      M    M
 14000    3.3  37.9   300   11    6   7.3   4.0   31.5  88.8     0.1      M    M
 13500    4.5  40.1   280   10    5   9.2   5.0   31.3  88.3    -0.1    685  3.5
 13000    5.6  42.1   265   10    5   6.3   3.5   31.0  87.9    -0.5    638  3.2
 12500    6.1  43.0   250   11    5   2.6   1.4   30.1  86.2    -1.5    609  3.1
 12000    6.5  43.7   235   12    6   3.2   1.8   29.0  84.2    -2.6    582  3.0
 11500    7.4  45.3   235   11    6   8.8   4.8   28.4  83.2    -3.1    539  2.7
 11000    8.7  47.7   235   10    5   8.4   4.6   28.2  82.8    -3.3    487  2.5
 10500    9.9  49.8   235    9    5   8.3   4.6   28.0  82.4    -3.6    436  2.2
 10250   10.5  50.9   230    9    5   8.3   4.6   27.9  82.2    -3.7    410  2.1
 10000   11.1  52.0   215    9    5   8.3   4.5   27.8  82.0    -3.8    385  2.0
  9750   11.7  53.1   205   10    5   8.3   4.6   27.7  81.8    -4.0    360  1.8
  9500   12.3  54.1   195   12    6   8.3   4.6   27.6  81.6    -4.1    334  1.7
  9250   12.9  55.2   185   13    7   8.3   4.6   27.5  81.4    -4.3    309  1.6
  9000   13.5  56.3   180   15    8   8.3   4.6   27.4  81.3    -4.4    284  1.4
  8750   14.1  57.4   175   15    8   8.3   4.5   27.2  81.0    -4.5    259  1.3
  8500   14.7  58.5   175   15    8   8.4   4.6   27.1  80.8    -4.7    233  1.2
  8250   15.3  59.5   170   16    8   7.9   4.4   27.0  80.6    -4.8    208  1.1
  8000   15.8  60.4   165   16    8   9.8   5.4   26.9  80.4    -5.0    183  0.9
  7750   16.3  61.3   165   17    9  -0.8  -0.4   26.7  80.1    -5.2    160  0.8
  7500   15.6  60.1   160   18    9 -12.8  -7.0   25.2  77.4    -6.7    176  0.9
  7250   14.8  58.6   160   19   10  -3.1  -1.7   23.8  74.8    -8.3    192  1.0
  7000   15.0  59.0   160   21   11   6.4   3.5   23.3  73.9    -8.8    179  0.9
  6750   15.5  59.9   155   19   10   8.2   4.5   23.1  73.6    -9.0    155  0.8
  6500   16.0  60.8   150   17    9  -0.4  -0.2   22.8  73.0    -9.3    135  0.7
  6250   15.7  60.3   140   16    8   0.0   0.0   21.8  71.2   -10.4    137  0.7
  6000   16.1  61.0   135   14    7  10.0   5.5   21.5  70.8   -10.7    115  0.6
  5750   16.9  62.4   125   13    7   9.6   5.3   21.6  70.8   -10.7     86  0.4
  5500   17.6  63.7   120   11    6  11.0   6.0   21.6  70.8   -10.7     57  0.3
  5250   18.3  64.9   110   10    5   5.9   3.2   21.6  70.9   -10.7     27  0.1
  5000   18.3  64.9   095    9    5  -6.6  -3.6   20.8  69.5   -11.5     22  0.1

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

           08/31/2015 at 0900 MDT          |       08/31/2015 at 1200 MDT
                                           |
K index... +28.7  LI... +269.9             | K index... +31.2  LI... +268.2
CAPE... +471.6  CIN... -39.5               | CAPE... +1337.2  CIN... -6.0
                                           |
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  250  32 16   1.6   0.9 | -64.3 -83.7  245  31 16   0.5   0.3
 45000 -60.9 -77.6  240  53 27   3.3   1.8 | -61.7 -79.1  240  54 28   4.4   2.4
 40000 -55.1 -67.2  230  56 29   8.2   4.5 | -54.5 -66.1  230  60 31   7.6   4.2
 38000 -50.1 -58.2  230  52 27   8.3   4.6 | -49.9 -57.8  230  57 29   7.7   4.2
 36000 -45.1 -49.2  230  48 25   8.3   4.6 | -45.3 -49.5  225  54 28   7.6   4.2
 34000 -40.1 -40.2  230  45 23   8.3   4.5 | -40.3 -40.5  225  51 26   8.4   4.6
 32000 -35.2 -31.4  230  42 22   8.1   4.4 | -35.3 -31.5  230  48 25   8.3   4.5
 30000 -30.5 -22.9  235  39 20   7.7   4.2 | -30.0 -22.0  235  44 23   7.7   4.2
 29000 -27.7 -17.9  240  37 19   7.7   4.2 | -27.7 -17.9  235  42 22   7.7   4.2
 28000 -25.4 -13.7  240  35 18   7.0   3.9 | -25.4 -13.7  240  40 21   6.7   3.7
 27000 -23.4 -10.1  240  33 17   6.9   3.8 | -23.5 -10.3  240  38 19   6.5   3.6
 26000 -21.3  -6.3  240  30 15   6.9   3.8 | -21.5  -6.7  235  35 18   6.5   3.6
 25000 -19.3  -2.7  245  27 14   6.8   3.7 | -19.6  -3.3  235  32 16   6.5   3.6
 24000 -17.4   0.7  245  25 13   6.0   3.3 | -17.6   0.3  240  29 15   6.6   3.6
 23000 -15.6   3.9  250  23 12   6.0   3.3 | -15.7   3.7  245  25 13   6.6   3.6
 22000 -13.8   7.2  255  21 11   6.2   3.4 | -13.7   7.3  255  23 12   6.6   3.6
 21000 -11.9  10.6  255  19 10   6.6   3.6 | -11.7  10.9  255  20 10   6.7   3.6
 20000 -10.0  14.0  260  17  9   6.7   3.7 |  -9.8  14.4  255  18  9   6.7   3.7
 19500  -9.0  15.8  260  16  8   6.8   3.7 |  -8.8  16.2  255  17  9   6.8   3.7
 19000  -8.1  17.4  265  15  8   6.4   3.5 |  -7.9  17.8  255  17  8   5.5   3.0
 18500  -7.2  19.0  265  16  8   6.4   3.5 |  -7.1  19.2  260  17  9   5.6   3.1
 18000  -6.2  20.8  270  16  8   6.3   3.4 |  -6.3  20.7  260  17  9   6.0   3.3
 17500  -5.3  22.5  270  16  8   6.0   3.3 |  -5.4  22.3  265  17  9   6.5   3.6
 17000  -4.5  23.9  275  16  8   5.8   3.2 |  -4.5  23.9  265  16  8   6.6   3.6
 16500  -3.5  25.7  280  15  8   7.4   4.1 |  -3.6  25.5  270  16  8   6.5   3.6
 16000  -2.4  27.7  280  15  8   7.4   4.1 |  -2.7  27.1  270  16  8   6.6   3.6
 15500  -1.4  29.5  280  14  7   7.1   3.9 |  -1.7  28.9  275  15  8   7.3   4.0
 15000  -0.4  31.3  280  14  7   6.9   3.8 |  -0.7  30.7  275  15  8   7.7   4.2
 14500   0.6  33.1  285  13  7   7.1   3.9 |   1.0  33.8  280  14  7   7.7   4.2
 14000   2.3  36.1  285  12  6   7.6   4.1 |   2.1  35.8  275  14  7   7.8   4.3
 13500   3.4  38.1  280  12  6   7.4   4.0 |   3.1  37.6  275  13  7   7.7   4.2
 13000   4.4  39.9  280  11  6   7.2   4.0 |   4.3  39.7  275  13  7   7.7   4.2
 12500   5.5  41.9  275  11  6   6.8   3.7 |   5.4  41.7  270  12  6   7.6   4.2
 12000   6.4  43.5  265  11  6   6.4   3.5 |   6.4  43.5  260  12  6   7.6   4.2
 11500   7.3  45.1  260  11  6   7.1   3.9 |   7.5  45.5  255  12  6   8.1   4.4
 11000   8.3  46.9  250  11  6   8.0   4.4 |   8.7  47.7  250  11  6   8.3   4.6
 10500   9.4  48.9  245  11  6   4.3   2.4 |   9.9  49.8  240  11  6   4.5   2.5
 10250   9.7  49.5  240  11  6   6.6   3.6 |  10.1  50.2  240  11  6   5.9   3.2
 10000  10.5  50.9  240  11  6  13.1   7.2 |  10.9  51.6  235  11  5  12.0   6.6
  9750  11.3  52.3  240  11  6  12.2   6.7 |  11.6  52.9  235  10  5  10.9   6.0
  9500  12.2  54.0  235  11  5   9.4   5.2 |  12.4  54.3  230  10  5   9.0   4.9
  9250  12.7  54.9  235  10  5   7.0   3.8 |  12.9  55.2  230   9  5   7.4   4.0
  9000  13.3  55.9  230  10  5   9.6   5.3 |  13.5  56.3  225   8  4   9.2   5.0
  8750  14.0  57.2  225   9  5  10.1   5.5 |  14.2  57.6  220   8  4   9.2   5.0
  8500  14.7  58.5  220   9  5   8.9   4.9 |  14.8  58.6  215   7  4   8.4   4.6
  8250  15.3  59.5  215   9  5   8.0   4.4 |  15.4  59.7  210   7  3   7.7   4.3
  8000  15.9  60.6  210   9  5   8.3   4.6 |  15.9  60.6  205   6  3   8.6   4.7
  7750  16.5  61.7  205   9  5   7.6   4.2 |  16.6  61.9  200   6  3   9.4   5.2
  7500  17.0  62.6  200  10  5   5.4   3.0 |  17.3  63.1  200   6  3   9.9   5.4
  7250  17.4  63.3  190  11  6   4.5   2.4 |  18.0  64.4  195   6  3  10.5   5.7
  7000  17.7  63.9  185  13  7   4.4   2.4 |  18.7  65.7  195   6  3   9.4   5.1
  6750  17.9  64.2  180  14  7   2.6   1.4 |  19.4  66.9  195   6  3   9.6   5.3
  6500  18.0  64.4  175  13  7   1.4   0.8 |  20.2  68.4  195   6  3  10.9   6.0
  6250  18.0  64.4  170  12  6   1.8   1.0 |  21.0  69.8  195   6  3  11.0   6.1
  6000  18.1  64.6  165  12  6   0.5   0.3 |  21.8  71.2  195   6  3  10.2   5.6
  5750  18.0  64.4  160  10  5   4.2   2.3 |  22.5  72.5  195   6  3  11.8   6.5
  5500  18.6  65.5  160   9  5   9.2   5.1 |  23.5  74.3  195   6  3  14.4   7.9
  5250  19.1  66.4  160   9  4   5.3   2.9 |  24.5  76.1  200   6  3  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/31/2015 at 1500 MDT          |       08/31/2015 at 1800 MDT
                                           |
K index... +29.5  LI... +269.5             | K index... +27.0  LI... +270.1
CAPE... +839.8  CIN... -7.9                | CAPE... +558.9  CIN... -35.6
                                           |
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 -64.5 -84.1  245  33 17   0.4   0.2 | -64.7 -84.5  245  35 18   0.6   0.3
 45000 -61.9 -79.4  245  52 27   4.9   2.7 | -61.9 -79.4  245  50 26   4.7   2.6
 40000 -54.2 -65.6  225  56 29   7.2   3.9 | -54.5 -66.1  240  53 28   7.2   3.9
 38000 -49.9 -57.8  225  54 28   7.2   4.0 | -50.2 -58.4  245  54 28   7.3   4.0
 36000 -45.5 -49.9  225  53 27   7.1   3.9 | -45.8 -50.4  250  55 28   7.1   3.9
 34000 -40.5 -40.9  225  49 25   8.6   4.7 | -40.7 -41.3  245  50 26   8.6   4.7
 32000 -35.3 -31.5  230  46 24   8.4   4.6 | -35.6 -32.1  240  44 23   8.5   4.7
 30000 -30.0 -22.0  235  42 22   7.7   4.2 | -30.3 -22.5  240  39 20   7.7   4.2
 29000 -27.7 -17.9  240  40 21   7.7   4.2 | -28.0 -18.4  245  36 19   7.7   4.2
 28000 -25.4 -13.7  245  39 20   7.4   4.0 | -25.7 -14.3  245  34 18   7.6   4.2
 27000 -23.2  -9.8  245  37 19   7.3   4.0 | -23.4 -10.1  250  32 16   7.6   4.1
 26000 -21.0  -5.8  240  35 18   7.3   4.0 | -21.1  -6.0  250  29 15   7.6   4.2
 25000 -18.8  -1.8  240  34 17   7.1   3.9 | -18.8  -1.8  255  26 14   7.4   4.1
 24000 -17.0   1.4  245  32 16   5.9   3.2 | -16.8   1.8  255  25 13   6.7   3.7
 23000 -15.3   4.5  250  30 15   5.9   3.2 | -14.8   5.4  260  24 12   6.7   3.7
 22000 -13.6   7.5  255  28 14   6.1   3.4 | -12.8   9.0  260  22 12   6.4   3.5
 21000 -11.6  11.1  260  24 13   6.7   3.7 | -11.1  12.0  265  21 11   5.5   3.0
 20000  -9.6  14.7  265  21 11   6.7   3.7 |  -9.5  14.9  270  19 10   5.5   3.0
 19500  -8.6  16.5  270  20 10   6.6   3.6 |  -8.7  16.3  275  19 10   5.4   2.9
 19000  -7.6  18.3  275  18  9   7.1   3.9 |  -7.7  18.1  275  18  9   7.6   4.2
 18500  -6.5  20.3  275  16  8   7.1   3.9 |  -6.6  20.1  280  18  9   7.5   4.1
 18000  -5.4  22.3  275  15  7   6.6   3.6 |  -5.5  22.1  285  18  9   7.7   4.2
 17500  -4.6  23.7  270  15  7   5.7   3.1 |  -4.3  24.3  285  17  9   8.0   4.4
 17000  -3.8  25.2  265  15  8   5.7   3.1 |  -3.2  26.2  285  16  8   8.2   4.5
 16500  -2.9  26.8  265  15  8   6.2   3.4 |  -2.1  28.2  285  15  8   6.7   3.7
 16000  -2.1  28.2  265  16  8   6.3   3.4 |  -1.1  30.0  280  15  8   6.9   3.8
 15500  -1.2  29.8  260  17  9   6.6   3.6 |  -0.2  31.6  275  15  8   7.0   3.8
 15000  -0.3  31.5  260  17  9   6.8   3.7 |   0.8  33.4  270  16  8   7.2   3.9
 14500   1.1  34.0  260  17  9   8.1   4.4 |   2.2  36.0  265  17  9   8.1   4.4
 14000   2.3  36.1  260  16  8   8.3   4.5 |   3.3  37.9  265  17  9   8.2   4.5
 13500   3.4  38.1  260  16  8   8.4   4.6 |   4.5  40.1  265  17  9   8.4   4.6
 13000   4.6  40.3  260  15  8   8.5   4.6 |   5.7  42.3  260  15  8   8.4   4.6
 12500   5.7  42.3  260  14  7   8.3   4.5 |   6.8  44.2  260  14  7   8.2   4.5
 12000   6.9  44.4  255  13  7   8.1   4.4 |   8.0  46.4  255  12  6   8.0   4.4
 11500   8.0  46.4  255  12  6   8.0   4.4 |   9.1  48.4  245  11  5   8.0   4.4
 11000   9.2  48.6  245  10  5   7.7   4.2 |  10.3  50.5  235   9  5   8.0   4.4
 10500  10.3  50.5  230   9  5   4.6   2.5 |  11.5  52.7  225   8  4   4.7   2.6
 10250  10.6  51.1  225   9  4   6.1   3.4 |  11.7  53.1  220   7  4   5.8   3.2
 10000  11.3  52.3  220   8  4  11.3   6.2 |  12.4  54.3  215   7  4  11.0   6.0
  9750  12.0  53.6  210   8  4  10.5   5.8 |  13.2  55.8  205   7  4  10.1   5.5
  9500  12.8  55.0  205   8  4   8.7   4.8 |  13.9  57.0  200   7  4   8.6   4.7
  9250  13.3  55.9  205   8  4   8.1   4.4 |  14.5  58.1  195   7  4   7.5   4.1
  9000  14.0  57.2  200   8  4  10.6   5.8 |  15.1  59.2  190   8  4   9.1   5.0
  8750  14.8  58.6  200   8  4  10.7   5.9 |  15.8  60.4  185   8  4   9.4   5.2
  8500  15.6  60.1  200   8  4  10.2   5.6 |  16.5  61.7  180   8  4   8.2   4.5
  8250  16.3  61.3  200   8  4   9.8   5.4 |  17.0  62.6  175   8  4   7.0   3.8
  8000  17.1  62.8  200   8  4  10.1   5.5 |  17.5  63.5  175   9  4   7.0   3.8
  7750  17.8  64.0  200   8  4  10.2   5.6 |  18.0  64.4  170   9  5   6.9   3.8
  7500  18.6  65.5  200   8  4   9.9   5.5 |  18.5  65.3  170   9  5   8.8   4.9
  7250  19.3  66.7  200   8  4   9.9   5.5 |  19.2  66.6  170   9  5  10.3   5.6
  7000  20.1  68.2  195   8  4   9.6   5.3 |  20.0  68.0  170   9  5   9.5   5.2
  6750  20.8  69.4  195   8  4  10.2   5.6 |  20.7  69.3  170   9  5   9.7   5.3
  6500  21.6  70.9  195   8  4  11.1   6.1 |  21.4  70.5  170   9  4  10.5   5.7
  6250  22.4  72.3  195   8  4  11.7   6.4 |  22.2  72.0  170   9  4  11.0   6.0
  6000  23.2  73.8  195   7  4   9.7   5.3 |  23.0  73.4  170   8  4   9.7   5.3
  5750  23.9  75.0  195   7  4  11.6   6.4 |  23.7  74.7  170   8  4   9.1   5.0
  5500  25.0  77.0  195   7  4  15.9   8.7 |  24.4  75.9  170   8  4  10.0   5.5
  5250  26.1  79.0  200   7  4  12.5   6.9 |  25.1  77.2  170   8  4   9.2   5.1
  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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