Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281239
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0639 MDT Friday, August 28, 2015

This forecast is for Friday, August 28, 2015:

If the trigger temperature of 79.0 F/26.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 874 ft/min (4.4 m/s)
   Maximum height of thermals.................. 15247 ft MSL (10408 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1030 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................. 11424 ft MSL (6585 ft AGL)
Thermal soaring outlook for Saturday 08/29..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:39:01 / 19:52:23 MDT
Total possible sunshine........... 13 hr 13 min 23 sec (793 min 23 sec)
Altitude of sun at 13:15:17 MDT... 60.49 degrees

Upper air data from rawinsonde observation taken on 08/28/2015 at 0600 MDT

Freezing level.................. 15336 ft MSL (10497 ft AGL)
Convective condensation level... 14342 ft MSL (9503 ft AGL)
Lifted condensation level....... 14760 ft MSL (9921 ft AGL)
Lifted index.................... -2.5
K index......................... +15.2

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  -64.3 -83.7   265   35   18   1.7   0.9   88.8 191.8    33.0      M    M
 45000  -59.9 -75.8   270   52   27  -2.5  -1.4   70.5 158.9    24.1      M    M
 40000  -56.2 -69.2   260   57   29   7.1   3.9   53.2 127.8    14.3      M    M
 38000  -51.9 -61.4   265   44   22   7.1   3.9   50.8 123.5    13.1      M    M
 36000  -47.2 -53.0   280   38   20   9.7   5.3   49.4 120.9    12.4      M    M
 34000  -42.1 -43.8   290   37   19   8.3   4.6   48.4 119.1    12.0      M    M
 32000  -36.3 -33.3   290   38   19   9.1   5.0   47.4 117.3    11.6      M    M
 30000  -32.3 -26.1   275   32   16   9.0   5.0   44.9 112.8    10.0      M    M
 29000  -29.5 -21.1   270   31   16  10.0   5.5   44.8 112.6    10.0      M    M
 28000  -27.0 -16.6   265   30   16   9.6   5.2   44.2 111.6     9.7      M    M
 27000  -24.1 -11.4   260   30   15   9.6   5.3   44.1 111.5     9.7      M    M
 26000  -21.7  -7.1   270   29   15   7.0   3.8   43.5 110.2     9.3      M    M
 25000  -19.5  -3.1   280   29   15   8.6   4.7   42.6 108.6     8.7      M    M
 24000  -17.2   1.0   285   27   14   8.0   4.4   41.9 107.4     8.2      M    M
 23000  -15.1   4.8   290   25   13   6.5   3.5   40.8 105.5     7.4      M    M
 22000  -13.0   8.6   295   23   12   5.3   2.9   39.9 103.8     6.7      M    M
 21000  -11.2  11.8   305   21   11   8.8   4.8   38.7 101.7     5.7      M    M
 20000   -8.8  16.2   315   20   10   7.4   4.0   37.9 100.3     5.2      M    M
 19500   -7.9  17.8   320   18    9   4.9   2.7   37.3  99.2     4.7      M    M
 19000   -7.2  19.0   320   17    9   4.7   2.6   36.4  97.6     3.9      M    M
 18500   -6.6  20.1   320   18    9   3.0   1.7   35.4  95.8     3.1      M    M
 18000   -6.1  21.0   320   20   10   4.0   2.2   34.4  93.9     2.2      M    M
 17500   -4.8  23.4   320   22   11   7.9   4.4   33.5  92.2     1.3      M    M
 17000   -3.6  25.5   325   23   12   7.8   4.3   33.1  91.7     1.0      M    M
 16500   -2.5  27.5   335   22   12   7.8   4.3   32.8  91.1     0.7      M    M
 16000   -1.3  29.7   345   23   12   7.8   4.3   32.5  90.5     0.4      M    M
 15500   -0.2  31.6   355   23   12   7.8   4.3   32.2  89.9     0.1      M    M
 15000    1.0  33.8   360   23   12   7.8   4.3   31.9  89.4    -0.2    842  4.3
 14500    2.1  35.8   355   22   12   7.8   4.3   31.5  88.7    -0.5    792  4.0
 14000    3.3  37.9   350   22   11   7.9   4.3   31.2  88.2    -0.8    743  3.8
 13500    4.4  39.9   350   19   10   7.4   4.1   30.8  87.5    -1.2    694  3.5
 13000    5.4  41.7   345   17    9   7.4   4.0   30.4  86.8    -1.7    649  3.3
 12500    6.4  43.5   345   15    8   7.4   4.1   30.0  86.1    -2.1    604  3.1
 12000    7.4  45.3   340   13    7   7.6   4.2   29.7  85.5    -2.6    559  2.8
 11500    8.6  47.5   345   11    6   7.6   4.2   29.3  84.8    -3.0    511  2.6
 11000    9.7  49.5   355   10    5   7.6   4.2   29.0  84.2    -3.3    463  2.3
 10500   10.8  51.4   005    9    5   7.6   4.2   28.7  83.6    -3.7    415  2.1
 10250   11.4  52.5   015    8    4   8.6   4.7   28.5  83.4    -3.8    390  2.0
 10000   11.9  53.4   030    8    4   5.8   3.2   28.4  83.1    -4.0    364  1.9
  9750   12.1  53.8   040    8    4   1.6   0.9   27.9  82.2    -4.5    352  1.8
  9500   12.2  54.0   050    9    5   6.2   3.4   27.3  81.2    -5.2    341  1.7
  9250   12.9  55.2   060   10    5   9.8   5.4   27.3  81.1    -5.2    314  1.6
  9000   13.6  56.5   070   11    6   9.4   5.2   27.3  81.1    -5.3    286  1.5
  8750   14.3  57.7   070   10    5   7.5   4.1   27.2  81.0    -5.3    258  1.3
  8500   14.5  58.1   075    9    4   0.4   0.2   26.8  80.2    -5.8    242  1.2
  8250   14.4  57.9   075    7    4   1.6   0.9   26.0  78.8    -6.7    239  1.2
  8000   14.7  58.5   080    6    3   7.2   4.0   25.6  78.1    -7.1    221  1.1
  7750   15.1  59.2   100    6    3   3.7   2.0   25.3  77.6    -7.5    202  1.0
  7500   15.0  59.0   120    7    3  -6.2  -3.4   24.5  76.2    -8.3    198  1.0
  7250   14.6  58.3   135    8    4   0.6   0.3   23.3  74.0    -9.5    204  1.0
  7000   15.2  59.4   145   10    5  10.1   5.5   23.2  73.8    -9.7    179  0.9
  6750   15.8  60.4   140    9    5   7.5   4.1   23.1  73.5    -9.8    154  0.8
  6500   16.3  61.3   130    9    4   8.3   4.6   22.9  73.3   -10.0    129  0.7
  6250   16.8  62.2   125    8    4   4.1   2.3   22.7  72.9   -10.3    107  0.5
  6000   17.0  62.6   115    8    4   4.6   2.5   22.2  72.0   -10.8     95  0.5
  5750   17.2  63.0   115    7    4  -5.2  -2.9   21.7  71.1   -11.4     82  0.4
  5500   16.4  61.5   125    7    3  -5.0  -2.7   20.2  68.4   -12.9     98  0.5
  5250   16.7  62.1   135    6    3   9.9   5.4   19.8  67.7   -13.4     81  0.4
  5000   17.0  62.6   145    6    3  -5.3  -2.9   19.5  67.1   -13.9     65  0.3

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

           08/28/2015 at 0900 MDT          |       08/28/2015 at 1200 MDT
                                           |
K index... +21.2  LI... +271.8             | K index... +10.6  LI... +270.6
CAPE... +190.4  CIN... -155.1              | CAPE... +390.8  CIN... -34.2
                                           |
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 -64.1 -83.4  275  33 17   1.5   0.8 | -64.3 -83.7  285  30 15   1.5   0.8
 45000 -61.2 -78.2  280  44 23   2.7   1.5 | -61.6 -78.9  290  38 20   2.2   1.2
 40000 -56.4 -69.5  285  37 19   7.7   4.2 | -57.3 -71.1  295  28 15   8.3   4.6
 38000 -51.6 -60.9  295  34 18   7.9   4.3 | -52.2 -62.0  300  28 14   8.5   4.7
 36000 -46.9 -52.4  305  33 17   7.8   4.3 | -47.0 -52.6  305  28 14   8.5   4.7
 34000 -41.7 -43.1  310  32 16   8.7   4.8 | -41.7 -43.1  310  27 14   8.9   4.9
 32000 -35.9 -32.6  310  32 16   8.8   4.8 | -35.8 -32.4  315  26 13   9.0   4.9
 30000 -31.1 -24.0  310  28 15   7.9   4.3 | -30.6 -23.1  315  23 12   8.6   4.7
 29000 -28.7 -19.7  305  27 14   7.9   4.3 | -28.0 -18.4  320  22 11   8.6   4.7
 28000 -26.4 -15.5  305  25 13   7.2   4.0 | -25.5 -13.9  320  21 11   7.2   3.9
 27000 -24.3 -11.7  305  24 12   7.2   3.9 | -23.4 -10.1  320  19 10   7.1   3.9
 26000 -22.2  -8.0  300  23 12   7.2   3.9 | -21.3  -6.3  315  18  9   7.1   3.9
 25000 -20.0  -4.0  300  22 11   7.2   4.0 | -19.2  -2.6  315  16  8   6.7   3.7
 24000 -17.9  -0.2  305  21 11   7.0   3.8 | -17.4   0.7  315  15  8   5.8   3.2
 23000 -15.8   3.6  310  20 10   7.0   3.8 | -15.7   3.7  325  14  7   5.8   3.2
 22000 -13.8   7.2  320  19 10   6.8   3.7 | -14.0   6.8  330  13  7   6.1   3.3
 21000 -11.9  10.6  325  18  9   6.4   3.5 | -12.1  10.2  340  12  6   6.3   3.5
 20000 -10.0  14.0  335  16  8   6.4   3.5 | -10.3  13.5  350  11  6   6.4   3.5
 19500  -9.1  15.6  340  16  8   6.6   3.6 |  -9.4  15.1  355  11  6   6.3   3.5
 19000  -8.2  17.2  345  16  8   5.1   2.8 |  -8.4  16.9  360  11  6   7.0   3.8
 18500  -7.0  19.4  350  15  8   5.2   2.9 |  -6.8  19.8  005  12  6   7.0   3.8
 18000  -6.3  20.7  355  15  8   5.5   3.0 |  -5.8  21.6  010  12  6   6.3   3.5
 17500  -5.5  22.1  355  14  7   5.6   3.0 |  -4.8  23.4  015  12  6   6.4   3.5
 17000  -4.7  23.5  355  14  7   6.2   3.4 |  -3.9  25.0  015  12  6   6.8   3.7
 16500  -3.7  25.3  355  14  7   6.8   3.7 |  -2.8  27.0  015  12  6   7.1   3.9
 16000  -2.8  27.0  355  14  7   7.0   3.9 |  -1.8  28.8  020  12  6   7.2   4.0
 15500  -1.6  29.1  350  14  7   8.8   4.8 |  -0.7  30.7  020  12  6   7.7   4.3
 15000  -0.4  31.3  350  14  7   8.7   4.8 |   0.5  32.9  020  12  6   7.7   4.2
 14500   0.9  33.6  350  15  8   8.9   4.9 |   1.6  34.9  020  12  6   8.0   4.4
 14000   2.2  36.0  355  15  8   8.9   4.9 |   2.8  37.0  020  13  7   8.0   4.4
 13500   3.5  38.3  355  15  8   9.1   5.0 |   3.9  39.0  020  13  7   8.4   4.6
 13000   4.8  40.6  355  15  8   9.1   5.0 |   5.2  41.4  020  13  7   8.5   4.6
 12500   6.2  43.2  360  15  8   8.9   4.9 |   6.4  43.5  025  14  7   8.7   4.8
 12000   7.5  45.5  360  15  8   8.8   4.8 |   7.6  45.7  025  14  7   8.9   4.9
 11500   8.8  47.8  005  15  8   8.7   4.8 |   8.9  48.0  030  14  7   8.7   4.8
 11000  10.0  50.0  010  14  7   8.5   4.7 |  10.1  50.2  035  14  7   8.5   4.7
 10500  11.2  52.2  015  14  7   7.4   4.1 |  11.3  52.3  035  14  7   7.8   4.3
 10250  11.7  53.1  015  14  7   7.4   4.1 |  11.8  53.2  040  14  7   8.6   4.7
 10000  12.3  54.1  020  13  7   9.3   5.1 |  12.5  54.5  040  13  7  10.1   5.6
  9750  13.0  55.4  025  13  7   9.5   5.2 |  13.2  55.8  040  13  7   9.9   5.5
  9500  13.7  56.7  025  13  7   8.3   4.6 |  13.9  57.0  040  13  7   8.9   4.9
  9250  14.2  57.6  030  12  6   7.1   3.9 |  14.5  58.1  045  13  7   7.9   4.3
  9000  14.7  58.5  035  12  6   8.1   4.5 |  15.1  59.2  045  12  6   8.6   4.7
  8750  15.3  59.5  040  11  6   8.6   4.7 |  15.8  60.4  045  12  6   8.6   4.7
  8500  15.9  60.6  040  11  5   6.5   3.6 |  16.4  61.5  050  11  6   7.5   4.1
  8250  16.2  61.2  045  10  5   5.2   2.9 |  16.8  62.2  050  10  5   6.7   3.7
  8000  16.6  61.9  045   9  5   5.2   2.9 |  17.3  63.1  050   9  5   7.3   4.0
  7750  16.9  62.4  050   8  4   3.8   2.1 |  17.9  64.2  055   8  4   8.0   4.4
  7500  17.0  62.6  055   7  4   2.3   1.3 |  18.4  65.1  055   7  4   8.2   4.5
  7250  17.1  62.8  060   6  3   1.8   1.0 |  18.9  66.0  055   6  3   8.2   4.5
  7000  17.2  63.0  070   6  3   2.0   1.1 |  19.5  67.1  060   6  3   8.6   4.7
  6750  17.3  63.1  080   5  3   1.9   1.0 |  20.0  68.0  060   5  3   9.9   5.5
  6500  17.4  63.3  090   5  3   2.0   1.1 |  20.8  69.4  060   5  2  10.7   5.9
  6250  17.5  63.5  095   5  2   1.5   0.8 |  21.6  70.9  060   5  2  10.3   5.7
  6000  17.6  63.7  105   4  2   3.6   1.9 |  22.3  72.1  060   4  2  11.2   6.1
  5750  18.0  64.4  110   5  2  10.2   5.6 |  23.3  73.9  060   4  2  17.7   9.7
  5500  18.9  66.0  105   4  2  14.9   8.2 |  25.0  77.0  060   4  2  25.9  14.2
  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

           08/28/2015 at 1500 MDT          |       08/28/2015 at 1800 MDT
                                           |
K index... +11.0  LI... +272.3             | K index... +13.5  LI... +272.6
CAPE... +49.2  CIN... -52.2                | CAPE... +46.2  CIN... -37.1
                                           |
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 -64.8 -84.6  295  25 13   1.3   0.7 | -65.4 -85.7  300  25 13   1.0   0.6
 45000 -62.1 -79.8  300  31 16   2.7   1.5 | -62.8 -81.0  305  30 15   3.1   1.7
 40000 -57.1 -70.8  295  25 13   8.4   4.6 | -57.1 -70.8  295  29 15   8.6   4.7
 38000 -51.9 -61.4  305  25 13   8.6   4.7 | -51.9 -61.4  300  26 14   8.7   4.7
 36000 -46.8 -52.2  310  25 13   8.6   4.7 | -46.7 -52.1  300  24 12   8.7   4.8
 34000 -40.8 -41.4  310  23 12   8.8   4.9 | -41.4 -42.5  300  21 11   8.8   4.8
 32000 -35.5 -31.9  310  21 11   9.0   5.0 | -36.1 -33.0  305  19 10   8.8   4.8
 30000 -30.2 -22.4  315  19 10   8.8   4.8 | -30.3 -22.5  310  18  9   8.7   4.8
 29000 -27.6 -17.7  315  18  9   8.8   4.8 | -27.7 -17.9  310  17  9   8.7   4.8
 28000 -25.1 -13.2  320  17  9   7.3   4.0 | -25.1 -13.2  310  17  9   8.4   4.6
 27000 -22.9  -9.2  315  16  8   7.3   4.0 | -22.5  -8.5  310  16  8   8.5   4.7
 26000 -20.7  -5.3  315  15  7   7.3   4.0 | -20.0  -4.0  310  16  8   8.5   4.7
 25000 -18.5  -1.3  310  14  7   6.8   3.7 | -17.4   0.7  310  16  8   7.0   3.8
 24000 -16.7   1.9  310  11  6   5.7   3.1 | -15.8   3.6  310  14  7   5.5   3.0
 23000 -15.1   4.8  315   9  5   5.7   3.1 | -14.1   6.6  310  11  6   5.5   3.0
 22000 -13.4   7.9  325   7  3   5.9   3.2 | -12.5   9.5  305   8  4   5.7   3.1
 21000 -11.5  11.3  335   6  3   6.2   3.4 | -10.8  12.6  305   6  3   5.8   3.2
 20000  -9.7  14.5  345   5  3   6.3   3.5 |  -9.1  15.6  310   3  2   5.9   3.2
 19500  -8.4  16.9  355   5  2   7.2   3.9 |  -8.2  17.2  320   2  1   6.1   3.3
 19000  -7.2  19.0  360   5  3   7.7   4.2 |  -7.2  19.0  340   2  1   8.0   4.4
 18500  -6.0  21.2  010   5  3   7.8   4.3 |  -6.0  21.2  360   3  1   7.9   4.3
 18000  -4.9  23.2  020   6  3   7.2   3.9 |  -4.8  23.4  010   3  2   7.8   4.3
 17500  -3.8  25.2  025   7  4   7.2   4.0 |  -3.7  25.3  020   4  2   7.8   4.3
 17000  -2.7  27.1  030   8  4   7.3   4.0 |  -2.5  27.5  030   4  2   7.8   4.3
 16500  -1.7  28.9  030   9  5   7.4   4.0 |  -1.4  29.5  035   5  2   8.2   4.5
 16000  -0.6  30.9  035  11  5   7.4   4.1 |  -0.2  31.6  040   5  3   8.2   4.5
 15500   0.6  33.1  035  11  6   8.0   4.4 |   1.1  34.0  045   5  3   8.4   4.6
 15000   1.7  35.1  035  12  6   8.0   4.4 |   2.3  36.1  045   6  3   8.4   4.6
 14500   2.9  37.2  035  12  6   8.3   4.5 |   4.1  39.4  045   7  4   8.4   4.6
 14000   4.1  39.4  040  12  6   8.3   4.6 |   5.3  41.5  045   7  4   8.4   4.6
 13500   5.3  41.5  040  12  6   8.5   4.6 |   6.5  43.7  040   8  4   8.7   4.8
 13000   6.5  43.7  040  11  6   8.5   4.7 |   7.8  46.0  040   8  4   8.8   4.8
 12500   7.7  45.9  040  11  6   8.5   4.7 |   9.1  48.4  040   9  5   8.7   4.8
 12000   8.9  48.0  040  11  5   8.6   4.7 |  10.3  50.5  040   9  5   8.7   4.7
 11500  10.2  50.4  040  10  5   8.5   4.7 |  11.6  52.9  040  10  5   8.9   4.9
 11000  11.4  52.5  040   9  5   8.2   4.5 |  12.8  55.0  040   9  5   9.0   5.0
 10500  12.6  54.7  040   9  5   4.6   2.5 |  14.0  57.2  040   9  5   5.2   2.9
 10250  12.8  55.0  040   8  4   5.8   3.2 |  14.4  57.9  045   9  5   7.1   3.9
 10000  13.5  56.3  040   7  4  11.4   6.2 |  15.1  59.2  045   9  4  11.1   6.1
  9750  14.3  57.7  040   7  3  10.5   5.8 |  15.9  60.6  045   8  4  10.2   5.6
  9500  15.0  59.0  040   6  3   8.4   4.6 |  16.6  61.9  045   8  4   8.0   4.4
  9250  15.5  59.9  040   6  3   6.4   3.5 |  17.1  62.8  050   8  4   7.1   3.9
  9000  16.0  60.8  035   5  3   9.3   5.1 |  17.7  63.9  050   7  4   8.8   4.8
  8750  16.7  62.1  035   5  2  10.2   5.6 |  18.3  64.9  055   6  3   8.5   4.7
  8500  17.4  63.3  035   4  2   9.5   5.2 |  19.0  66.2  055   6  3   8.1   4.4
  8250  18.1  64.6  035   4  2   9.0   4.9 |  19.5  67.1  055   5  3   7.8   4.3
  8000  18.8  65.8  035   4  2  10.0   5.5 |  20.1  68.2  055   4  2   7.7   4.2
  7750  19.5  67.1  035   3  2  10.8   5.9 |  20.7  69.3  060   3  2   8.0   4.4
  7500  20.3  68.5  035   3  2  10.0   5.5 |  21.3  70.3  060   3  1   9.0   4.9
  7250  21.0  69.8  035   3  2   9.7   5.3 |  21.9  71.4  060   3  1   9.2   5.0
  7000  21.7  71.1  040   3  1   9.8   5.4 |  22.6  72.7  065   2  1   9.3   5.1
  6750  22.5  72.5  040   3  1  10.0   5.5 |  23.3  73.9  070   2  1  10.1   5.5
  6500  23.2  73.8  040   2  1  10.5   5.8 |  24.1  75.4  070   2  1  10.4   5.7
  6250  24.0  75.2  040   2  1  10.4   5.7 |  24.9  76.8  075   2  1  10.6   5.8
  6000  24.8  76.6  040   2  1  11.0   6.0 |  25.6  78.1  080   2  1   9.7   5.3
  5750  25.8  78.4  040   2  1  18.1   9.9 |  26.3  79.3  085   1  1   9.3   5.1
  5500  27.5  81.5  035   2  1  27.6  15.1 |  27.0  80.6  080   1  1  10.0   5.5
  5250     M     M    M   M  M     M     M |  27.7  81.9  075   1  1   9.4   5.2
  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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