Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 061237
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0637 MDT Monday, July 6, 2015

This forecast is for Monday, July 6, 2015:

If the trigger temperature of 79.7 F/26.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 632 ft/min (3.2 m/s)
   Maximum height of thermals.................. 14683 ft MSL (9844 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10042 ft MSL (5203 ft AGL)
Thermal soaring outlook for Tuesday 07/07...... Good

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

Remarks...

Sunrise/Sunset.................... 05:54:32 / 20:43:16 MDT
Total possible sunshine........... 14 hr 48 min 44 sec (888 min 44 sec)
Altitude of sun at 13:18:54 MDT... 73.51 degrees

Upper air data from rawinsonde observation taken on 07/06/2015 at 0600 MDT

Freezing level.................. 15454 ft MSL (10615 ft AGL)
Convective condensation level... 12131 ft MSL (7292 ft AGL)
Lifted condensation level....... 13163 ft MSL (8323 ft AGL)
Lifted index.................... -3.1
K index......................... +24.7

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   235   15    8   6.0   3.3   87.1 188.7    32.5      M    M
 45000  -61.2 -78.2   225   40   20   2.0   1.1   67.8 154.1    22.9      M    M
 40000  -52.5 -62.5   220   45   23   8.5   4.6   57.4 135.3    17.6      M    M
 38000  -47.8 -54.0   220   40   20   8.2   4.5   55.8 132.5    16.9      M    M
 36000  -43.5 -46.3   225   34   18   8.7   4.8   53.7 128.6    15.9      M    M
 34000  -38.6 -37.5   225   35   18   8.6   4.7   52.3 126.2    15.3      M    M
 32000  -33.1 -27.6   230   37   19   9.7   5.3   52.0 125.6    15.4      M    M
 30000  -27.5 -17.5   235   24   12   7.7   4.2   50.7 123.2    14.8      M    M
 29000  -25.7 -14.3   225   25   13   1.0   0.5   49.3 120.7    13.8      M    M
 28000  -23.8 -10.8   230   22   11   7.9   4.3   48.0 118.3    12.9      M    M
 27000  -21.9  -7.4   235   20   10   6.4   3.5   46.8 116.2    12.1      M    M
 26000  -20.0  -4.0   250   16    8   7.1   3.9   45.4 113.7    11.2      M    M
 25000  -17.5   0.5   275   14    7   8.8   4.8   44.9 112.8    10.9      M    M
 24000  -14.9   5.2   270   10    5   6.6   3.6   44.5 112.1    10.7      M    M
 23000  -13.1   8.4   260   11    6   6.1   3.4   43.2 109.7     9.7      M    M
 22000  -11.4  11.5   255   12    6   6.6   3.6   41.8 107.3     8.6      M    M
 21000   -9.9  14.2   235   12    6   3.1   1.7   40.2 104.4     7.2      M    M
 20000   -9.0  15.8   270   17    9   5.1   2.8   37.9 100.2     5.3      M    M
 19500   -7.8  18.0   275   17    9   6.0   3.3   37.4  99.4     5.1      M    M
 19000   -6.7  19.9   290   16    8   8.5   4.7   36.9  98.4     4.8      M    M
 18500   -6.1  21.0   310   16    8   2.6   1.4   36.0  96.8     4.0      M    M
 18000   -5.7  21.7   325   18    9   5.4   2.9   34.8  94.7     2.9      M    M
 17500   -4.5  23.9   325   23   12   7.8   4.3   34.5  94.0     2.7      M    M
 17000   -3.6  25.5   320   28   14   4.4   2.4   33.8  92.9     2.1      M    M
 16500   -2.6  27.3   320   26   13   8.2   4.5   32.8  91.0     1.0      M    M
 16000   -1.2  29.8   320   24   12   8.8   4.8   32.6  90.7     0.9      M    M
 15500    0.2  32.4   325   22   11   9.1   5.0   32.5  90.4     0.8      M    M
 15000    1.2  34.2   325   20   10   5.9   3.3   32.1  89.8     0.3      M    M
 14500    1.9  35.4   330   18    9   5.6   3.1   31.4  88.6    -0.4    811  4.1
 14000    2.8  37.0   335   17    9   7.6   4.1   30.9  87.7    -0.9    769  3.9
 13500    3.8  38.8   330   15    8   7.6   4.2   30.6  87.0    -1.4    725  3.7
 13000    4.8  40.6   330   13    7   8.2   4.5   30.2  86.4    -1.9    682  3.5
 12500    6.0  42.8   325   11    6   8.8   4.8   30.1  86.1    -2.1    629  3.2
 12000    7.3  45.1   320   10    5   8.8   4.8   29.9  85.9    -2.3    575  2.9
 11500    8.6  47.5   315    7    3   8.8   4.8   29.8  85.6    -2.5    522  2.7
 11000    9.9  49.8   300    3    2   8.8   4.8   29.6  85.3    -2.7    469  2.4
 10500   11.2  52.2   230    2    1   8.8   4.8   29.5  85.0    -2.8    415  2.1
 10250   11.8  53.2   215    1    1   8.9   4.9   29.4  84.9    -2.9    389  2.0
 10000   12.5  54.5   000    0    0   8.8   4.8   29.3  84.8    -3.0    362  1.8
  9750   13.1  55.6   020    1    0   9.2   5.0   29.3  84.7    -3.1    336  1.7
  9500   13.7  56.7   020    1    1   7.6   4.2   29.2  84.5    -3.2    309  1.6
  9250   14.1  57.4   020    2    1   4.1   2.3   28.9  84.0    -3.5    290  1.5
  9000   14.4  57.9   020    3    2   3.3   1.8   28.4  83.1    -4.0    275  1.4
  8750   14.6  58.3   065    1    1   2.9   1.6   27.9  82.2    -4.6    261  1.3
  8500   14.6  58.3   135    2    1   2.5   1.4   27.3  81.2    -5.3    254  1.3
  8250   14.8  58.6   155    4    2   2.8   1.6   26.8  80.2    -5.9    241  1.2
  8000   15.0  59.0   160    7    3   2.7   1.5   26.2  79.2    -6.4    228  1.2
  7750   15.1  59.2   155    5    3   2.8   1.5   25.7  78.3    -7.0    215  1.1
  7500   15.3  59.5   145    4    2   2.6   1.4   25.2  77.3    -7.5    203  1.0
  7250   15.5  59.9   125    2    1   3.4   1.8   24.6  76.3    -8.1    190  1.0
  7000   15.8  60.4   075    2    1   5.8   3.2   24.2  75.6    -8.5    173  0.9
  6750   16.3  61.3   070    2    1   6.9   3.8   24.0  75.2    -8.8    151  0.8
  6500   16.8  62.2   075    2    1   6.6   3.6   23.8  74.8    -9.0    129  0.7
  6250   17.3  63.1   080    2    1   6.8   3.7   23.5  74.4    -9.3    107  0.5
  6000   17.8  64.0   085    2    1   6.5   3.6   23.3  74.0    -9.5     85  0.4
  5750   18.3  64.9   090    2    1   7.4   4.1   23.1  73.6    -9.8     62  0.3
  5500   18.8  65.8   095    3    1   4.0   2.2   22.9  73.2   -10.1     40  0.2
  5250   18.7  65.7   100    3    2  -4.3  -2.4   22.1  71.8   -10.9     34  0.2
  5000   18.2  64.8   105    4    2  -6.7  -3.7   20.9  69.6   -12.1     43  0.2

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

           07/06/2015 at 0900 MDT          |       07/06/2015 at 1200 MDT
                                           |
K index... +20.3  LI... +269.4             | K index... +12.0  LI... +268.2
CAPE... +769.5  CIN... -26.1               | CAPE... +1398.6  CIN... -9.3
                                           |
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 -64.2 -83.6  230  25 13   2.0   1.1 | -64.0 -83.2  235  26 13   1.7   1.0
 45000 -60.1 -76.2  230  34 17   4.4   2.4 | -60.0 -76.0  230  37 19   4.8   2.6
 40000 -52.4 -62.3  235  35 18   7.4   4.0 | -52.0 -61.6  230  38 20   6.8   3.7
 38000 -48.0 -54.4  230  32 17   7.3   4.0 | -47.9 -54.2  225  33 17   6.8   3.7
 36000 -43.6 -46.5  225  30 16   7.5   4.1 | -43.8 -46.8  220  29 15   6.9   3.8
 34000 -38.6 -37.5  230  27 14   8.5   4.7 | -39.0 -38.2  220  28 15   8.0   4.4
 32000 -33.5 -28.3  235  23 12   8.4   4.6 | -34.2 -29.6  225  28 15   7.9   4.3
 30000 -29.1 -20.4  245  20 10   7.2   4.0 | -29.4 -20.9  230  24 12   8.1   4.4
 29000 -26.9 -16.4  245  19 10   7.2   4.0 | -26.3 -15.3  235  21 11   8.1   4.4
 28000 -24.2 -11.6  250  18  9   7.7   4.2 | -24.0 -11.2  235  19 10   6.8   3.7
 27000 -21.9  -7.4  255  17  9   7.7   4.2 | -21.9  -7.4  240  18  9   7.0   3.8
 26000 -19.6  -3.3  255  15  8   7.7   4.2 | -19.9  -3.8  240  17  9   7.0   3.8
 25000 -17.3   0.9  260  14  7   7.4   4.0 | -17.8  -0.0  245  16  8   6.8   3.7
 24000 -15.2   4.6  260  14  7   6.8   3.8 | -15.9   3.4  255  17  9   6.6   3.6
 23000 -13.2   8.2  265  14  7   6.8   3.8 | -13.9   7.0  265  18  9   6.7   3.7
 22000 -11.1  12.0  265  14  7   6.0   3.3 | -12.0  10.4  270  20 10   6.4   3.5
 21000  -9.7  14.5  275  15  8   4.8   2.6 | -10.2  13.6  275  19 10   6.1   3.3
 20000  -8.3  17.1  280  15  8   4.8   2.6 |  -8.3  17.1  285  19 10   6.1   3.3
 19500  -7.6  18.3  285  16  8   4.7   2.6 |  -7.4  18.7  290  19 10   6.1   3.4
 19000  -6.8  19.8  285  16  8   5.4   3.0 |  -6.5  20.3  290  18  9   5.3   2.9
 18500  -6.0  21.2  290  15  8   5.4   2.9 |  -5.6  21.9  295  16  8   5.4   3.0
 18000  -5.2  22.6  295  15  8   5.7   3.1 |  -4.8  23.4  300  15  8   5.8   3.2
 17500  -4.4  24.1  300  16  8   6.1   3.3 |  -3.9  25.0  300  15  8   6.0   3.3
 17000  -3.5  25.7  305  17  9   6.0   3.3 |  -3.0  26.6  305  15  8   6.0   3.3
 16500  -2.5  27.5  310  18  9   7.6   4.1 |  -2.0  28.4  310  15  8   7.4   4.1
 16000  -1.4  29.5  310  19 10   7.4   4.1 |  -0.9  30.4  310  15  8   7.3   4.0
 15500  -0.3  31.5  315  19 10   8.0   4.4 |   0.2  32.4  315  16  8   7.5   4.1
 15000   0.9  33.6  315  20 10   8.2   4.5 |   1.3  34.3  315  16  8   7.6   4.2
 14500   2.1  35.8  310  20 10   8.1   4.4 |   2.5  36.5  315  16  8   7.8   4.3
 14000   3.2  37.8  310  19 10   7.8   4.3 |   4.2  39.6  315  15  8   8.0   4.4
 13500   4.8  40.6  310  18  9   7.2   3.9 |   5.3  41.5  320  14  7   7.1   3.9
 13000   5.7  42.3  315  16  8   7.2   3.9 |   6.3  43.3  320  13  7   6.9   3.8
 12500   6.6  43.9  315  14  7   8.4   4.6 |   7.2  45.0  320  12  6   7.4   4.0
 12000   7.8  46.0  315  13  6   9.3   5.1 |   8.2  46.8  325  11  6   7.8   4.3
 11500   9.1  48.4  315  11  6   8.9   4.9 |   9.2  48.6  325  10  5   8.4   4.6
 11000  10.1  50.2  315  10  5   7.8   4.3 |  10.4  50.7  325   9  5   8.7   4.8
 10500  11.2  52.2  315   8  4   4.0   2.2 |  11.6  52.9  325   8  4   4.9   2.7
 10250  11.3  52.3  315   7  4   4.0   2.2 |  11.8  53.2  325   8  4   5.8   3.2
 10000  11.9  53.4  310   7  3   9.0   5.0 |  12.5  54.5  320   7  4  11.8   6.5
  9750  12.5  54.5  310   6  3   8.3   4.5 |  13.2  55.8  320   6  3  11.0   6.0
  9500  13.0  55.4  310   5  3   6.5   3.6 |  13.9  57.0  320   6  3   8.6   4.7
  9250  13.4  56.1  310   5  3   5.2   2.9 |  14.3  57.7  315   5  2   6.5   3.6
  9000  13.8  56.8  305   4  2   7.3   4.0 |  14.8  58.6  315   4  2   8.3   4.5
  8750  14.4  57.9  305   4  2   7.6   4.2 |  15.4  59.7  305   3  2   8.2   4.5
  8500  14.9  58.8  305   3  2   6.6   3.6 |  15.9  60.6  300   3  1   7.4   4.1
  8250  15.3  59.5  305   3  1   5.9   3.2 |  16.4  61.5  290   2  1   6.8   3.7
  8000  15.8  60.4  305   2  1   5.5   3.0 |  16.8  62.2  285   2  1   7.6   4.2
  7750  16.1  61.0  295   1  0   4.9   2.7 |  17.4  63.3  275   2  1   8.5   4.7
  7500  16.5  61.7  000   0  0   5.2   2.8 |  18.0  64.4  270   2  1   9.7   5.3
  7250  16.9  62.4  150   1  0   5.0   2.7 |  18.7  65.7  265   2  1  10.3   5.7
  7000  17.2  63.0  145   1  1   5.7   3.1 |  19.5  67.1  265   2  1  10.2   5.6
  6750  17.7  63.9  150   2  1   6.9   3.8 |  20.2  68.4  260   2  1  10.7   5.9
  6500  18.2  64.8  140   2  1   7.1   3.9 |  21.0  69.8  260   2  1  10.9   6.0
  6250  18.7  65.7  130   2  1   7.2   4.0 |  21.9  71.4  260   2  1  11.2   6.2
  6000  19.2  66.6  125   2  1   6.6   3.6 |  22.7  72.9  255   2  1  10.0   5.5
  5750  19.7  67.5  115   2  1   9.1   5.0 |  23.5  74.3  260   3  1  12.8   7.0
  5500  20.5  68.9  110   2  1  12.0   6.6 |  24.6  76.3  260   3  1  16.7   9.2
  5250  21.3  70.3  110   2  1   9.8   5.4 |  25.7  78.3  260   3  1  13.7   7.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/06/2015 at 1500 MDT          |       07/06/2015 at 1800 MDT
                                           |
K index... +11.1  LI... +270.4             | K index... +23.6  LI... +270.0
CAPE... +550.0  CIN... -17.0               | CAPE... +610.4  CIN... -18.7
                                           |
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 -63.7 -82.7  235  26 13   2.2   1.2 | -63.2 -81.8  225  25 13   2.9   1.6
 45000 -59.2 -74.6  225  40 20   4.1   2.2 | -58.6 -73.5  220  41 21   3.1   1.7
 40000 -52.3 -62.1  220  45 23   7.3   4.0 | -52.8 -63.0  220  50 26   7.9   4.3
 38000 -48.0 -54.4  220  41 21   7.3   4.0 | -48.1 -54.6  220  50 26   7.9   4.3
 36000 -43.6 -46.5  215  38 19   7.4   4.0 | -43.4 -46.1  215  49 25   7.9   4.3
 34000 -38.8 -37.8  220  34 18   8.2   4.5 | -38.5 -37.3  220  44 23   8.2   4.5
 32000 -33.8 -28.8  220  31 16   8.0   4.4 | -33.6 -28.5  230  39 20   8.0   4.4
 30000 -28.8 -19.8  230  28 14   7.4   4.1 | -28.8 -19.8  235  32 17   7.9   4.3
 29000 -26.6 -15.9  230  26 14   7.4   4.1 | -25.9 -14.6  235  28 15   7.9   4.3
 28000 -24.4 -11.9  235  25 13   7.6   4.2 | -23.6 -10.5  240  26 13   6.8   3.7
 27000 -22.1  -7.8  235  23 12   7.6   4.2 | -21.5  -6.7  240  25 13   6.9   3.8
 26000 -19.8  -3.6  235  20 10   7.6   4.2 | -19.4  -2.9  235  24 12   6.9   3.8
 25000 -17.5   0.5  240  18  9   7.1   3.9 | -17.4   0.7  235  23 12   6.8   3.7
 24000 -15.6   3.9  245  17  9   6.4   3.5 | -15.4   4.3  240  20 10   6.6   3.6
 23000 -13.7   7.3  255  17  9   6.4   3.5 | -13.5   7.7  245  17  9   6.7   3.7
 22000 -11.9  10.6  265  17  9   6.5   3.6 | -11.5  11.3  255  15  8   6.4   3.5
 21000 -10.0  14.0  270  17  9   6.5   3.6 |  -9.8  14.4  260  14  7   6.1   3.4
 20000  -8.1  17.4  280  17  9   6.6   3.6 |  -8.0  17.6  265  13  7   6.2   3.4
 19500  -7.2  19.0  280  17  9   6.7   3.7 |  -7.1  19.2  265  12  6   6.2   3.4
 19000  -6.2  20.8  285  16  8   6.1   3.4 |  -6.2  20.8  270  12  6   6.4   3.5
 18500  -5.1  22.8  290  15  8   6.4   3.5 |  -5.2  22.6  275  11  5   6.4   3.5
 18000  -4.1  24.6  290  14  7   6.5   3.6 |  -4.2  24.4  280  10  5   6.7   3.7
 17500  -3.0  26.6  295  13  7   6.7   3.7 |  -3.1  26.4  285   9  4   7.2   3.9
 17000  -2.0  28.4  300  12  6   6.7   3.7 |  -2.0  28.4  295   8  4   7.2   4.0
 16500  -0.9  30.4  310  11  6   7.1   3.9 |  -1.0  30.2  305   7  4   7.3   4.0
 16000   0.1  32.2  315  11  6   7.1   3.9 |   0.1  32.2  315   7  3   7.3   4.0
 15500   1.2  34.2  320  11  6   7.0   3.8 |   1.2  34.2  330   6  3   7.4   4.1
 15000   2.2  36.0  325  11  6   7.0   3.9 |   2.2  36.0  335   6  3   7.6   4.2
 14500   3.2  37.8  330  11  5   7.3   4.0 |   3.2  37.8  340   6  3   7.7   4.2
 14000   4.8  40.6  330   9  5   7.8   4.3 |   4.8  40.6  345   6  3   7.7   4.2
 13500   5.8  42.4  330   9  4   7.6   4.2 |   5.8  42.4  350   6  3   7.9   4.3
 13000   6.8  44.2  335   8  4   7.6   4.2 |   6.9  44.4  355   6  3   8.0   4.4
 12500   7.8  46.0  340   7  4   7.7   4.2 |   8.0  46.4  360   6  3   8.4   4.6
 12000   8.9  48.0  340   6  3   7.7   4.2 |   9.2  48.6  360   6  3   8.7   4.8
 11500  10.0  50.0  345   5  3   8.0   4.4 |  10.5  50.9  355   5  3   8.7   4.8
 11000  11.1  52.0  340   5  3   8.0   4.4 |  11.7  53.1  350   5  3   8.2   4.5
 10500  12.3  54.1  340   5  2   4.5   2.5 |  12.9  55.2  345   5  2   5.2   2.9
 10250  12.5  54.5  340   5  2   5.7   3.1 |  13.2  55.8  345   5  2   6.3   3.4
 10000  13.3  55.9  335   4  2  11.3   6.2 |  13.9  57.0  345   5  2  11.0   6.0
  9750  14.0  57.2  335   4  2  10.2   5.6 |  14.7  58.5  340   5  2  10.2   5.6
  9500  14.7  58.5  335   4  2   9.5   5.2 |  15.4  59.7  335   5  2   8.5   4.7
  9250  15.3  59.5  335   4  2   9.0   4.9 |  15.9  60.6  335   5  2   7.3   4.0
  9000  15.9  60.6  335   4  2  10.0   5.5 |  16.6  61.9  330   5  2   8.9   4.9
  8750  16.6  61.9  330   4  2   9.9   5.4 |  17.2  63.0  330   5  2   8.4   4.6
  8500  17.3  63.1  330   4  2  10.2   5.6 |  17.8  64.0  325   5  2   9.6   5.2
  8250  18.0  64.4  330   4  2  10.4   5.7 |  18.5  65.3  325   5  2  10.7   5.8
  8000  18.8  65.8  330   4  2   9.9   5.4 |  19.3  66.7  325   5  2   9.8   5.4
  7750  19.5  67.1  330   4  2   9.7   5.3 |  19.9  67.8  320   5  2   9.4   5.2
  7500  20.2  68.4  330   4  2  10.2   5.6 |  20.6  69.1  315   5  2   9.8   5.4
  7250  21.0  69.8  330   4  2  10.6   5.8 |  21.4  70.5  315   4  2  10.1   5.5
  7000  21.8  71.2  325   4  2  10.0   5.5 |  22.1  71.8  315   4  2   9.9   5.4
  6750  22.5  72.5  325   4  2  10.1   5.6 |  22.9  73.2  315   4  2  10.0   5.5
  6500  23.3  73.9  325   4  2  11.0   6.0 |  23.6  74.5  310   4  2  10.6   5.8
  6250  24.1  75.4  320   4  2  11.5   6.3 |  24.5  76.1  310   4  2  11.2   6.1
  6000  25.0  77.0  320   4  2  10.1   5.6 |  25.3  77.5  310   4  2  10.0   5.5
  5750  25.7  78.3  320   3  2  13.0   7.1 |  26.0  78.8  305   4  2  10.1   5.6
  5500  26.9  80.4  320   4  2  17.3   9.5 |  26.8  80.2  305   4  2  12.0   6.6
  5250  28.1  82.6  325   4  2  14.0   7.7 |  27.6  81.7  310   4  2  11.2   6.1
  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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