Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 271247
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0647 MDT Wednesday, July 27, 2016

This forecast is for Wednesday, July 27, 2016:

If the trigger temperature of 89.0 F/31.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1601 ft/min (8.1 m/s)
   Maximum height of thermals.................. 21440 ft MSL (16601 ft AGL)

Forecast maximum temperature................... 100.0 F/38.2 C
Time of trigger temperature.................... 1800 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................. 13368 ft MSL (8529 ft AGL)
Thermal soaring outlook for Thursday 07/28..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:10:46 / 20:30:46 MDT
Total possible sunshine........... 14 hr 20 min 1 sec (860 min 1 sec)
Altitude of sun at 13:20:35 MDT... 69.83 degrees

Upper air data from rawinsonde observation taken on 07/27/2016 at 0600 MDT

Freezing level.................. 16396 ft MSL (11557 ft AGL)
Convective condensation level... 17544 ft MSL (12705 ft AGL)
Lifted condensation level....... 18860 ft MSL (14021 ft AGL)
Lifted index.................... -2.8
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  -65.1 -85.2   320   29   15   4.4   2.4   84.6 184.3    27.3      M    M
 45000  -58.8 -73.8   285   30   15   9.5   5.2   69.5 157.1    19.9      M    M
 40000  -47.5 -53.5   305   41   21   1.8   1.0   64.5 148.1    17.9      M    M
 38000  -46.4 -51.5   300   52   27   7.2   4.0   57.5 135.5    13.5      M    M
 36000  -42.0 -43.6   315   34   18   7.0   3.9   55.4 131.7    12.4      M    M
 34000  -38.0 -36.4   335   42   22   7.2   3.9   52.8 127.0    10.8      M    M
 32000  -33.5 -28.3   345   45   23   7.5   4.1   51.0 123.8     9.8      M    M
 30000  -28.8 -19.8   330   33   17   8.4   4.6   48.5 119.3     8.1      M    M
 29000  -26.3 -15.3   335   35   18   7.4   4.1   47.9 118.3     7.8      M    M
 28000  -24.2 -11.6   320   17    9   6.0   3.3   46.8 116.3     7.1      M    M
 27000  -22.6  -8.7   330   21   11   5.4   2.9   45.1 113.2     5.8      M    M
 26000  -21.0  -5.8   340   26   13   5.8   3.2   43.5 110.3     4.6      M    M
 25000  -19.0  -2.2   345   30   15   7.0   3.8   42.4 108.3     3.7      M    M
 24000  -16.9   1.6   340   35   18   7.0   3.9   41.3 106.4     2.9      M    M
 23000  -14.8   5.4   335   41   21   7.0   3.8   40.4 104.7     2.2      M    M
 22000  -13.1   8.4   330   35   18   4.5   2.5   39.0 102.1     1.0      M    M
 21000  -11.7  10.9   325   28   15   4.6   2.5   37.1  98.8    -0.6   1574  8.0
 20000  -10.1  13.8   320   36   19   9.8   5.4   35.9  96.5    -1.9   1495  7.6
 19500   -8.7  16.3   320   37   19   9.4   5.2   35.8  96.5    -1.9   1437  7.3
 19000   -7.4  18.7   320   34   18   8.3   4.5   35.6  96.2    -2.1   1384  7.0
 18500   -6.1  21.0   320   30   15   9.0   4.9   35.4  95.8    -2.3   1331  6.8
 18000   -4.8  23.4   320   26   13   9.0   4.9   35.3  95.5    -2.5   1277  6.5
 17500   -3.5  25.7   315   22   11   9.0   4.9   35.2  95.3    -2.7   1223  6.2
 17000   -2.2  28.0   315   18    9   9.6   5.3   35.1  95.2    -2.8   1169  5.9
 16500    0.0  32.0   310   15    7   9.8   5.4   35.1  95.2    -2.8   1081  5.5
 16000    1.5  34.7   310   13    7   9.7   5.3   35.1  95.2    -2.8   1022  5.2
 15500    2.9  37.2   315   13    6   9.7   5.3   35.1  95.2    -2.8    964  4.9
 15000    4.4  39.9   320   12    6   9.7   5.3   35.1  95.1    -2.9    906  4.6
 14500    5.9  42.6   320   12    6   9.8   5.4   35.1  95.2    -2.9    847  4.3
 14000    7.3  45.1   325   12    6   9.8   5.4   35.1  95.2    -2.9    789  4.0
 13500    8.7  47.7   320   11    6   9.0   4.9   35.0  95.1    -3.0    732  3.7
 13000   10.0  50.0   310   11    5   8.8   4.9   34.9  94.8    -3.2    678  3.4
 12500   11.3  52.3   305   10    5   8.8   4.9   34.7  94.5    -3.3    625  3.2
 12000   12.6  54.7   295   10    5   8.9   4.9   34.6  94.3    -3.5    572  2.9
 11500   13.9  57.0   285   10    5   8.9   4.9   34.5  94.0    -3.7    518  2.6
 11000   15.1  59.2   280   10    5   8.9   4.9   34.3  93.8    -3.9    465  2.4
 10500   16.4  61.5   270   10    5   7.7   4.2   34.2  93.5    -4.1    413  2.1
 10250   16.9  62.4   270    9    5   6.5   3.6   33.9  93.1    -4.4    391  2.0
 10000   17.4  63.3   275    9    5   6.9   3.8   33.7  92.6    -4.7    369  1.9
  9750   17.9  64.2   280    8    4   6.8   3.7   33.4  92.2    -4.9    347  1.8
  9500   18.4  65.1   280    8    4   6.8   3.7   33.2  91.8    -5.2    325  1.6
  9250   18.8  65.8   285    7    4   6.8   3.7   33.0  91.4    -5.4    303  1.5
  9000   19.3  66.7   290    7    4   6.7   3.7   32.8  91.0    -5.7    281  1.4
  8750   19.8  67.6   265    4    2   7.1   3.9   32.5  90.6    -5.9    259  1.3
  8500   20.3  68.5   205    4    2   5.8   3.2   32.3  90.2    -6.2    237  1.2
  8250   20.5  68.9   175    7    4  -0.8  -0.5   31.8  89.2    -6.8    224  1.1
  8000   20.2  68.4   160   10    5  -0.3  -0.2   30.9  87.6    -7.7    224  1.1
  7750   20.4  68.7   155   10    5   3.0   1.7   30.3  86.6    -8.3    211  1.1
  7500   20.6  69.1   150    8    4   4.0   2.2   29.8  85.6    -8.9    198  1.0
  7250   20.8  69.4   140    7    4  -4.3  -2.4   29.2  84.5    -9.4    186  0.9
  7000   20.2  68.4   130    6    3  -4.3  -2.4   27.8  82.1   -10.8    197  1.0
  6750   20.4  68.7   120    6    3   7.6   4.2   27.3  81.2   -11.3    182  0.9
  6500   21.0  69.8   110    7    3   7.9   4.3   27.2  80.9   -11.5    157  0.8
  6250   21.6  70.9   105    7    4   8.2   4.5   27.1  80.7   -11.6    132  0.7
  6000   22.2  72.0   100    8    4   6.7   3.7   26.9  80.5   -11.8    107  0.5
  5750   22.4  72.3   100    8    4  -0.5  -0.3   26.5  79.6   -12.3     92  0.5
  5500   22.3  72.1   105    8    4   3.1   1.7   25.6  78.2   -13.2     88  0.4
  5250   22.6  72.7   110    7    4  -5.5  -3.0   25.1  77.3   -13.7     74  0.4
  5000   20.9  69.6   115    7    4 -38.2 -20.9   22.7  72.9   -16.2    117  0.6

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

           07/27/2016 at 0900 MDT          |       07/27/2016 at 1200 MDT
                                           |
K index... +21.5  LI... +273.0             | K index... +22.7  LI... +273.0
CAPE... +83.3  CIN... -53.0                | CAPE... +114.4  CIN... -55.3
                                           |
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  310  22 11   2.4   1.3 | -64.4 -83.9  315  19 10   2.2   1.2
 45000 -58.5 -73.3  305  35 18   6.3   3.4 | -58.2 -72.8  310  36 18   6.6   3.6
 40000 -48.9 -56.0  315  40 21   5.6   3.0 | -48.7 -55.7  315  42 21   5.3   2.9
 38000 -45.5 -49.9  315  39 20   5.6   3.0 | -45.5 -49.9  315  37 19   5.3   2.9
 36000 -42.1 -43.8  320  38 19   6.9   3.8 | -42.3 -44.1  315  33 17   6.5   3.6
 34000 -37.6 -35.7  325  36 19   7.5   4.1 | -37.8 -36.0  320  33 17   7.5   4.1
 32000 -33.1 -27.6  335  36 18   7.6   4.2 | -33.4 -28.1  325  32 17   7.6   4.1
 30000 -28.6 -19.5  340  34 17   7.5   4.1 | -28.8 -19.8  325  30 15   7.6   4.2
 29000 -26.4 -15.5  340  33 17   7.6   4.1 | -26.0 -14.8  330  28 14   7.6   4.1
 28000 -24.2 -11.6  340  32 16   5.3   2.9 | -23.9 -11.0  335  27 14   6.3   3.4
 27000 -22.6  -8.7  340  31 16   5.4   3.0 | -22.0  -7.6  335  27 14   6.3   3.5
 26000 -21.0  -5.8  340  30 15   5.4   3.0 | -20.1  -4.2  340  27 14   6.3   3.5
 25000 -19.4  -2.9  340  28 15   6.5   3.6 | -18.2  -0.8  345  27 14   6.8   3.7
 24000 -17.0   1.4  340  26 14   8.1   4.4 | -16.2   2.8  345  25 13   6.9   3.8
 23000 -14.6   5.7  340  25 13   8.1   4.4 | -14.1   6.6  340  23 12   6.9   3.8
 22000 -11.6  11.1  340  23 12   6.7   3.7 | -12.0  10.4  340  21 11   8.0   4.4
 21000  -9.6  14.7  340  23 12   6.9   3.8 |  -9.6  14.7  340  20 11   8.0   4.4
 20000  -7.5  18.5  335  24 12   6.9   3.8 |  -7.2  19.0  340  20 10   8.0   4.4
 19500  -6.5  20.3  335  24 12   6.0   3.3 |  -6.0  21.2  340  19 10   7.4   4.1
 19000  -5.7  21.7  330  24 12   5.6   3.1 |  -5.0  23.0  335  19 10   6.5   3.5
 18500  -4.9  23.2  330  24 12   5.5   3.0 |  -4.0  24.8  335  19 10   6.5   3.6
 18000  -3.9  25.0  325  23 12   7.8   4.3 |  -3.1  26.4  330  19 10   5.8   3.2
 17500  -2.8  27.0  325  21 11   7.9   4.3 |  -2.2  28.0  330  19 10   5.9   3.3
 17000  -1.7  28.9  320  19 10   8.8   4.8 |  -1.4  29.5  325  20 10   6.9   3.8
 16500  -0.4  31.3  320  17  9   9.2   5.1 |  -0.3  31.5  325  18 10   8.3   4.6
 16000   0.9  33.6  315  15  8   9.3   5.1 |   0.9  33.6  320  17  9   8.6   4.7
 15500   2.2  36.0  310  13  7   9.2   5.1 |   2.1  35.8  315  15  8   9.0   5.0
 15000   3.5  38.3  305  12  6   9.3   5.1 |   3.4  38.1  315  13  7   9.0   5.0
 14500   4.9  40.8  300  11  5   9.6   5.3 |   4.7  40.5  315  11  6   9.4   5.2
 14000   6.3  43.3  295  10  5   9.6   5.3 |   6.8  44.2  310  10  5   9.6   5.3
 13500   7.6  45.7  290  10  5   9.3   5.1 |   8.1  46.6  310   9  5   9.2   5.0
 13000   9.0  48.2  290  10  5   9.2   5.1 |   9.5  49.1  305   9  5   9.3   5.1
 12500  10.4  50.7  290  10  5   9.1   5.0 |  10.9  51.6  305   9  5   9.1   5.0
 12000  11.7  53.1  285  11  5   8.9   4.9 |  12.2  54.0  305  10  5   9.1   5.0
 11500  13.0  55.4  285  11  6   8.4   4.6 |  13.5  56.3  305  10  5   8.7   4.8
 11000  14.2  57.6  285  11  6   7.5   4.1 |  14.7  58.5  300  11  6   9.1   5.0
 10500  15.4  59.7  280  12  6   3.5   1.9 |  15.7  60.3  300  11  6   4.9   2.7
 10250  15.5  59.9  280  11  6   5.0   2.8 |  16.1  61.0  300  11  6   8.7   4.8
 10000  16.2  61.2  280  11  6  11.3   6.2 |  16.8  62.2  295  11  5  10.7   5.9
  9750  17.0  62.6  275  10  5  10.4   5.7 |  17.6  63.7  295  10  5   9.6   5.3
  9500  17.7  63.9  275  10  5   7.7   4.2 |  18.2  64.8  295  10  5   6.5   3.6
  9250  18.1  64.6  270   9  4   4.8   2.6 |  18.6  65.5  290  10  5   6.8   3.7
  9000  18.6  65.5  270   7  4   7.5   4.1 |  19.2  66.6  290   9  5   9.2   5.0
  8750  19.1  66.4  260   6  3   8.9   4.9 |  19.9  67.8  285   8  4   8.3   4.5
  8500  19.7  67.5  250   5  3   7.1   3.9 |  20.4  68.7  280   7  4   7.1   3.9
  8250  20.1  68.2  235   5  2   5.7   3.1 |  21.0  69.8  280   6  3   6.8   3.7
  8000  20.5  68.9  220   5  2   6.1   3.3 |  21.5  70.7  275   5  3   7.0   3.8
  7750  20.9  69.6  205   5  3   5.5   3.0 |  22.0  71.6  265   4  2   8.2   4.5
  7500  21.2  70.2  195   6  3   3.4   1.9 |  22.7  72.9  260   4  2   9.5   5.2
  7250  21.4  70.5  185   7  3   2.0   1.1 |  23.3  73.9  260   3  2   9.6   5.3
  7000  21.6  70.9  180   7  4   2.7   1.5 |  24.0  75.2  255   3  2   9.3   5.1
  6750  21.8  71.2  170   8  4   2.5   1.4 |  24.7  76.5  250   3  2  10.1   5.6
  6500  21.9  71.4  165   8  4   1.8   1.0 |  25.5  77.9  250   3  2  11.0   6.1
  6250  22.0  71.6  160   7  3   1.0   0.5 |  26.3  79.3  250   3  2  10.8   5.9
  6000  22.1  71.8  155   5  3   2.6   1.4 |  27.1  80.8  250   3  2  10.9   6.0
  5750  22.6  72.7  145   5  3  10.5   5.7 |  28.0  82.4  250   3  2  13.4   7.4
  5500  23.7  74.7  145   5  2  18.7  10.3 |  29.1  84.4  250   3  2  15.6   8.5
  5250     M     M    M   M  M     M     M |  30.2  86.4  255   3  2  14.0   7.7
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/27/2016 at 1500 MDT          |       07/27/2016 at 1800 MDT
                                           |
K index... +7.2  LI... +273.6              | K index... +16.3  LI... +273.9
CAPE... +114.6  CIN... -77.7               | CAPE... +46.5  CIN... -55.7
                                           |
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 -64.6 -84.3  305  16  8   2.3   1.3 | -64.8 -84.6  285  13  7   1.9   1.0
 45000 -58.1 -72.6  315  31 16   6.9   3.8 | -58.6 -73.5  295  25 13   7.0   3.9
 40000 -48.4 -55.1  320  38 20   5.1   2.8 | -48.6 -55.5  315  36 19   5.3   2.9
 38000 -45.3 -49.5  320  35 18   5.1   2.8 | -45.3 -49.5  315  36 19   5.3   2.9
 36000 -42.2 -44.0  315  33 17   6.6   3.6 | -42.1 -43.8  315  36 18   6.8   3.7
 34000 -37.7 -35.9  315  31 16   7.5   4.1 | -37.6 -35.7  320  33 17   7.5   4.1
 32000 -33.2 -27.8  320  30 15   7.5   4.1 | -33.1 -27.6  325  30 15   7.5   4.1
 30000 -28.3 -18.9  320  27 14   7.3   4.0 | -28.8 -19.8  325  27 14   7.2   4.0
 29000 -26.1 -15.0  325  25 13   7.3   4.0 | -26.1 -15.0  325  26 13   7.2   4.0
 28000 -24.0 -11.2  325  24 13   6.6   3.6 | -23.9 -11.0  330  24 13   6.8   3.8
 27000 -22.0  -7.6  330  24 12   6.6   3.6 | -21.9  -7.4  335  23 12   6.8   3.8
 26000 -20.0  -4.0  340  23 12   6.6   3.6 | -19.8  -3.6  340  22 11   6.8   3.8
 25000 -18.0  -0.4  345  23 12   7.3   4.0 | -17.8  -0.0  345  21 11   7.5   4.1
 24000 -15.8   3.6  345  22 11   7.4   4.1 | -15.5   4.1  345  20 10   7.6   4.1
 23000 -13.6   7.5  345  20 10   7.4   4.1 | -13.2   8.2  350  19 10   7.6   4.1
 22000 -11.3  11.7  345  19 10   8.2   4.5 | -11.0  12.2  350  18  9   7.6   4.2
 21000  -8.9  16.0  345  19 10   8.2   4.5 |  -8.7  16.3  350  18  9   7.6   4.2
 20000  -6.5  20.3  340  19 10   8.2   4.5 |  -6.4  20.5  345  18  9   7.7   4.2
 19500  -5.3  22.5  340  18  9   8.4   4.6 |  -5.3  22.5  345  18  9   8.1   4.4
 19000  -4.0  24.8  340  18  9   8.7   4.8 |  -4.0  24.8  345  18  9   8.5   4.7
 18500  -2.7  27.1  340  18  9   8.8   4.8 |  -2.7  27.1  345  18  9   8.6   4.7
 18000  -1.4  29.5  340  18  9   7.5   4.1 |  -1.5  29.3  345  17  9   8.6   4.7
 17500  -0.3  31.5  340  18  9   7.6   4.1 |  -0.2  31.6  345  17  9   8.6   4.7
 17000   0.8  33.4  340  17  9   7.4   4.0 |   1.1  34.0  350  16  8   8.4   4.6
 16500   1.9  35.4  345  16  8   7.1   3.9 |   2.2  36.0  350  16  8   8.1   4.5
 16000   2.9  37.2  350  15  8   7.1   3.9 |   3.4  38.1  350  15  8   8.2   4.5
 15500   3.9  39.0  350  14  7   6.9   3.8 |   4.5  40.1  355  15  7   8.4   4.6
 15000   4.9  40.8  350  13  7   7.0   3.8 |   5.7  42.3  355  14  7   8.5   4.6
 14500   6.0  42.8  345  12  6   8.0   4.4 |   6.9  44.4  355  13  7   9.0   4.9
 14000   7.8  46.0  340  11  6   8.3   4.5 |   8.9  48.0  360  12  6   9.1   5.0
 13500   9.0  48.2  340  11  5   9.0   4.9 |  10.3  50.5  360  11  6   9.4   5.2
 13000  10.3  50.5  335  10  5   8.9   4.9 |  11.6  52.9  360  10  5   9.4   5.2
 12500  11.6  52.9  330   9  5   8.9   4.9 |  13.0  55.4  355  10  5   9.5   5.2
 12000  12.9  55.2  325   8  4   8.9   4.9 |  14.4  57.9  355   9  5   9.5   5.2
 11500  14.2  57.6  320   7  4   9.2   5.1 |  15.7  60.3  350   8  4   8.9   4.9
 11000  15.6  60.1  310   7  3   9.9   5.4 |  17.0  62.6  350   7  4   9.2   5.1
 10500  16.6  61.9  305   6  3   5.7   3.1 |  18.0  64.4  345   7  3   5.8   3.2
 10250  17.2  63.0  305   6  3  10.2   5.6 |  18.6  65.5  340   6  3   9.8   5.4
 10000  18.0  64.4  300   6  3  11.3   6.2 |  19.4  66.9  340   6  3  10.2   5.6
  9750  18.9  66.0  295   6  3  10.7   5.9 |  20.1  68.2  335   5  3  10.0   5.5
  9500  19.6  67.3  295   6  3   8.2   4.5 |  20.8  69.4  330   5  3   8.2   4.5
  9250  20.1  68.2  290   5  3   8.3   4.6 |  21.3  70.3  325   4  2   7.8   4.3
  9000  20.8  69.4  290   5  3  10.0   5.5 |  22.0  71.6  315   4  2   8.9   4.9
  8750  21.5  70.7  290   5  3   9.5   5.2 |  22.6  72.7  305   4  2   8.5   4.7
  8500  22.2  72.0  290   5  3   9.6   5.3 |  23.2  73.8  300   4  2   8.0   4.4
  8250  22.8  73.0  285   5  3   9.6   5.3 |  23.8  74.8  290   4  2   7.8   4.3
  8000  23.4  74.1  285   5  3   9.5   5.2 |  24.4  75.9  285   4  2   8.0   4.4
  7750  24.1  75.4  285   5  3   9.8   5.4 |  25.0  77.0  280   4  2   8.4   4.6
  7500  24.8  76.6  285   5  3  10.2   5.6 |  25.6  78.1  275   4  2   9.1   5.0
  7250  25.6  78.1  280   5  3  10.3   5.6 |  26.3  79.3  270   4  2   9.3   5.1
  7000  26.4  79.5  280   5  3  10.2   5.6 |  27.0  80.6  270   4  2   9.2   5.0
  6750  27.1  80.8  280   5  3  10.8   5.9 |  27.7  81.9  265   4  2   9.9   5.4
  6500  27.9  82.2  275   5  3  11.2   6.1 |  28.5  83.3  265   4  2  10.5   5.8
  6250  28.8  83.8  275   5  3  11.2   6.2 |  29.2  84.6  260   4  2  10.8   5.9
  6000  29.6  85.3  275   5  3  10.6   5.8 |  30.0  86.0  260   4  2   9.9   5.4
  5750  30.4  86.7  275   5  3  13.1   7.2 |  30.7  87.3  260   4  2  10.0   5.5
  5500  31.5  88.7  275   5  3  16.2   8.9 |  31.5  88.7  260   4  2  11.3   6.2
  5250  32.7  90.9  275   5  3  13.8   7.6 |  32.4  90.3  265   4  2  10.2   5.6
  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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