Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201242
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0642 MDT Wednesday, July 20, 2016

This forecast is for Wednesday, July 20, 2016:

If the trigger temperature of 80.6 F/27.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 596 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14548 ft MSL (9709 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
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................. 11039 ft MSL (6200 ft AGL)
Thermal soaring outlook for Thursday 07/21..... Good

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

Remarks...

Sunrise/Sunset.................... 06:04:55 / 20:36:20 MDT
Total possible sunshine........... 14 hr 31 min 26 sec (871 min 26 sec)
Altitude of sun at 13:20:30 MDT... 71.32 degrees

Upper air data from rawinsonde observation taken on 07/20/2016 at 0600 MDT

Freezing level.................. 16146 ft MSL (11307 ft AGL)
Convective condensation level... 13346 ft MSL (8507 ft AGL)
Lifted condensation level....... 14013 ft MSL (9174 ft AGL)
Lifted index.................... -2.4
K index......................... +29.1

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  -66.9 -88.4   225   16    8 -14.0  -7.7   81.8 179.2    28.8      M    M
 45000  -61.7 -79.1   250    6    3   8.6   4.7   66.0 150.8    21.1      M    M
 40000  -52.6 -62.7   235   16    8   7.6   4.2   57.2 135.0    16.7      M    M
 38000  -48.0 -54.4   210   20   10   7.6   4.2   55.5 131.8    15.9      M    M
 36000  -42.1 -43.8   215   22   11   8.7   4.8   54.4 129.9    15.7      M    M
 34000  -36.9 -34.4   220   23   12   8.8   4.8   53.6 128.4    15.4      M    M
 32000  -31.6 -24.9   220   23   12   7.5   4.1   52.8 127.0    15.2      M    M
 30000  -27.3 -17.1   225   16    8   8.3   4.6   50.8 123.5    14.0      M    M
 29000  -24.8 -12.6   220   16    8   8.3   4.6   50.2 122.3    13.7      M    M
 28000  -22.4  -8.3   210   16    8   8.4   4.6   49.6 121.3    13.4      M    M
 27000  -20.1  -4.2   205   16    8   4.8   2.6   48.8 119.9    12.9      M    M
 26000  -18.5  -1.3   195   15    8   7.4   4.1   47.2 117.0    11.7      M    M
 25000  -16.1   3.0   180   15    8   6.1   3.4   46.6 115.9    11.3      M    M
 24000  -14.3   6.3   175   13    7   6.0   3.3   45.3 113.5    10.3      M    M
 23000  -12.8   9.0   190   12    6   5.3   2.9   43.6 110.5     9.1      M    M
 22000  -11.8  10.8   205   12    6   4.6   2.5   41.4 106.6     7.2      M    M
 21000   -9.8  14.4   230   14    7   6.9   3.8   40.4 104.8     6.4      M    M
 20000   -7.6  18.3   215   16    8   2.4   1.3   38.7 101.7     4.9      M    M
 19500   -7.2  19.0   220   17    9   3.9   2.1   37.6  99.6     3.9      M    M
 19000   -6.4  20.5   220   18    9   7.7   4.2   36.8  98.3     3.3      M    M
 18500   -5.1  22.8   215   16    8   8.6   4.7   36.6  97.9     3.1      M    M
 18000   -3.9  25.0   205   15    8   8.7   4.8   36.4  97.5     2.9      M    M
 17500   -2.6  27.3   200   15    8   8.6   4.7   36.2  97.2     2.7      M    M
 17000   -1.3  29.7   190   14    7   8.2   4.5   36.1  96.9     2.6      M    M
 16500   -0.6  30.9   180   14    7   5.1   2.8   35.3  95.6     1.9      M    M
 16000    0.4  32.7   175   14    7   6.8   3.8   34.8  94.7     1.5      M    M
 15500    1.5  34.7   185   12    6   7.0   3.9   34.4  93.9     1.0      M    M
 15000    2.5  36.5   195   11    6   6.0   3.3   33.8  92.9     0.5      M    M
 14500    3.2  37.8   205   10    5   6.0   3.3   33.2  91.8    -0.1    789  4.0
 14000    4.0  39.2   215   10    5   5.9   3.2   32.6  90.7    -0.8    750  3.8
 13500    5.0  41.0   215    8    4   8.0   4.4   32.1  89.7    -1.3    707  3.6
 13000    6.2  43.2   220    7    4   8.2   4.5   31.8  89.2    -1.6    655  3.3
 12500    7.4  45.3   220    5    3   8.2   4.5   31.6  88.8    -1.8    604  3.1
 12000    8.7  47.7   225    4    2   8.1   4.5   31.3  88.4    -2.0    552  2.8
 11500    9.9  49.8   250    4    2   6.9   3.8   31.1  87.9    -2.3    500  2.5
 11000   10.6  51.1   270    6    3   4.9   2.7   30.3  86.6    -3.1    464  2.4
 10500   11.2  52.2   280    7    4   4.5   2.5   29.6  85.2    -3.9    431  2.2
 10250   11.5  52.7   280    6    3   6.8   3.7   29.2  84.5    -4.4    415  2.1
 10000   12.1  53.8   280    6    3   8.8   4.8   29.1  84.3    -4.5    389  2.0
  9750   12.8  55.0   280    5    3   8.3   4.5   29.0  84.2    -4.6    363  1.8
  9500   13.4  56.1   285    5    3   8.4   4.6   28.9  84.0    -4.7    337  1.7
  9250   14.0  57.2   285    5    2   8.4   4.6   28.8  83.8    -4.8    311  1.6
  9000   14.6  58.3   285    4    2   8.4   4.6   28.7  83.7    -4.9    285  1.4
  8750   15.2  59.4   295    4    2   8.4   4.6   28.6  83.5    -5.1    259  1.3
  8500   15.8  60.4   300    5    2   8.4   4.6   28.5  83.3    -5.2    233  1.2
  8250   16.4  61.5   310    5    3   8.4   4.6   28.4  83.1    -5.3    208  1.1
  8000   17.1  62.8   315    6    3   8.4   4.6   28.3  82.9    -5.4    182  0.9
  7750   17.7  63.9   315    7    4   8.4   4.6   28.2  82.7    -5.6    156  0.8
  7500   18.3  64.9   315    8    4   8.4   4.6   28.1  82.5    -5.7    130  0.7
  7250   18.9  66.0   315    9    5   8.4   4.6   28.0  82.3    -5.8    104  0.5
  7000   19.5  67.1   315   11    6   8.2   4.5   27.9  82.1    -5.9     78  0.4
  6750   20.1  68.2   315    9    5   9.0   5.0   27.7  81.9    -6.1     52  0.3
  6500   20.8  69.4   310    6    3   6.1   3.3   27.6  81.7    -6.2     26  0.1
  6250   20.9  69.6   305    4    2   0.2   0.1   27.1  80.8    -6.8     13  0.1
  6000   20.9  69.6   275    1    1  -0.9  -0.5   26.3  79.3    -7.6      9  0.0
  5750   20.9  69.6   150    1    1   4.6   2.5   25.6  78.2    -8.3      M    M
  5500   21.5  70.7   125    3    2  10.0   5.5   25.5  77.9    -8.4      M    M
  5250   22.1  71.8   115    5    3   3.5   1.9   25.4  77.7    -8.6      M    M
  5000   22.0  71.6   115    7    3  -5.5  -3.0   24.5  76.1    -9.4      M    M

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

           07/20/2016 at 0900 MDT          |       07/20/2016 at 1200 MDT
                                           |
K index... +32.6  LI... +269.9             | K index... +30.1  LI... +269.6
CAPE... +720.2  CIN... -6.7                | CAPE... +842.6  CIN... -2.2
                                           |
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 -65.6 -86.1  195  15  8   1.3   0.7 | -65.6 -86.1  205  19 10   1.0   0.5
 45000 -61.2 -78.2  190  15  7   5.8   3.2 | -61.3 -78.3  205  22 11   6.0   3.3
 40000 -51.8 -61.2  230  16  8   8.2   4.5 | -51.6 -60.9  220  20 11   8.4   4.6
 38000 -46.9 -52.4  230  19 10   8.2   4.5 | -46.0 -50.8  220  21 11   8.4   4.6
 36000 -41.4 -42.5  225  22 11   8.2   4.5 | -40.9 -41.6  220  22 11   8.4   4.6
 34000 -36.5 -33.7  225  22 11   8.2   4.5 | -35.9 -32.6  215  22 11   8.4   4.6
 32000 -31.6 -24.9  225  22 11   8.8   4.8 | -30.9 -23.6  215  22 12   8.9   4.9
 30000 -26.9 -16.4  220  19 10   7.9   4.4 | -26.3 -15.3  215  21 11   7.7   4.2
 29000 -24.5 -12.1  215  17  9   8.0   4.4 | -24.0 -11.2  215  20 10   7.7   4.2
 28000 -22.3  -8.1  210  16  8   6.9   3.8 | -21.8  -7.2  215  19 10   6.8   3.7
 27000 -20.2  -4.4  205  15  8   7.0   3.8 | -19.8  -3.6  215  18  9   6.9   3.8
 26000 -18.1  -0.6  205  14  7   7.0   3.9 | -17.8  -0.0  215  16  8   6.9   3.8
 25000 -16.1   3.0  200  13  7   6.8   3.7 | -15.8   3.6  215  15  7   6.5   3.6
 24000 -14.2   6.4  200  13  6   6.6   3.6 | -14.0   6.8  220  13  7   6.2   3.4
 23000 -12.3   9.9  205  12  6   6.6   3.6 | -12.2  10.0  230  12  6   6.2   3.4
 22000 -10.4  13.3  205  11  6   6.0   3.3 |  -9.9  14.2  235  10  5   5.8   3.2
 21000  -8.3  17.1  205  10  5   5.6   3.1 |  -8.2  17.2  240  10  5   5.8   3.2
 20000  -6.7  19.9  210  10  5   5.6   3.1 |  -6.5  20.3  240  10  5   5.8   3.2
 19500  -5.9  21.4  210  10  5   5.3   2.9 |  -5.7  21.7  240  10  5   5.6   3.1
 19000  -5.2  22.6  210  10  5   5.2   2.9 |  -4.9  23.2  240  10  5   5.5   3.0
 18500  -4.4  24.1  210  10  5   5.2   2.8 |  -4.1  24.6  240  10  5   5.5   3.0
 18000  -3.6  25.5  210  10  5   5.6   3.1 |  -3.3  26.1  245  10  5   5.7   3.1
 17500  -2.8  27.0  210  10  5   5.6   3.1 |  -2.5  27.5  245  10  5   5.6   3.1
 17000  -2.0  28.4  210  10  5   5.7   3.1 |  -1.7  28.9  245  10  5   5.7   3.1
 16500  -1.2  29.8  210  10  5   5.8   3.2 |  -0.8  30.6  245  10  5   5.7   3.1
 16000  -0.4  31.3  210  10  5   5.9   3.2 |  -0.0  32.0  245  10  5   5.8   3.2
 15500   0.5  32.9  210  10  5   6.5   3.6 |   0.9  33.6  245  10  5   6.5   3.6
 15000   1.5  34.7  210  10  5   6.5   3.6 |   1.8  35.2  245  10  5   6.5   3.6
 14500   2.4  36.3  210  10  5   6.2   3.4 |   2.7  36.9  245  10  5   6.8   3.7
 14000   3.3  37.9  210   9  5   6.2   3.4 |   3.7  38.7  245  10  5   6.8   3.7
 13500   4.2  39.6  215   9  5   7.0   3.8 |   4.7  40.5  240  10  5   6.8   3.7
 13000   5.2  41.4  215   8  4   7.1   3.9 |   5.7  42.3  240   9  5   6.8   3.7
 12500   6.2  43.2  220   8  4   7.2   3.9 |   6.6  43.9  240   9  5   6.6   3.6
 12000   7.2  45.0  225   7  4   7.3   4.0 |   7.5  45.5  240   8  4   6.6   3.6
 11500   8.2  46.8  225   7  3   9.1   5.0 |   8.5  47.3  240   8  4   7.0   3.8
 11000   9.7  49.5  230   7  3  10.4   5.7 |   9.5  49.1  240   7  3   7.3   4.0
 10500  11.1  52.0  235   7  3   8.1   4.4 |  10.5  50.9  235   6  3   7.5   4.1
 10250  11.6  52.9  240   7  3   8.0   4.4 |  11.1  52.0  235   6  3   9.1   5.0
 10000  12.3  54.1  240   7  3  10.8   6.0 |  11.8  53.2  235   5  3  10.3   5.6
  9750  13.1  55.6  240   7  3  10.5   5.7 |  12.5  54.5  235   5  3  10.1   5.6
  9500  13.8  56.8  240   6  3   8.9   4.9 |  13.2  55.8  235   5  2   9.4   5.1
  9250  14.4  57.9  245   6  3   7.6   4.2 |  13.8  56.8  230   5  2   8.8   4.8
  9000  15.0  59.0  245   6  3   8.7   4.8 |  14.5  58.1  230   5  2  10.2   5.6
  8750  15.6  60.1  240   6  3   8.8   4.8 |  15.3  59.5  230   4  2  10.7   5.8
  8500  16.2  61.2  240   6  3   7.4   4.1 |  16.0  60.8  225   4  2   9.3   5.1
  8250  16.7  62.1  240   6  3   6.5   3.6 |  16.6  61.9  225   4  2   8.6   4.7
  8000  17.3  63.1  240   6  3   7.3   4.0 |  17.3  63.1  220   4  2   9.2   5.1
  7750  17.8  64.0  235   6  3   7.3   4.0 |  18.0  64.4  220   4  2   9.8   5.4
  7500  18.3  64.9  230   6  3   6.1   3.3 |  18.7  65.7  215   4  2   9.8   5.4
  7250  18.7  65.7  220   6  3   5.7   3.1 |  19.4  66.9  215   4  2  10.0   5.5
  7000  19.2  66.6  215   6  3   6.2   3.4 |  20.1  68.2  215   4  2   9.3   5.1
  6750  19.6  67.3  205   6  3   5.7   3.1 |  20.8  69.4  215   4  2   9.5   5.2
  6500  20.0  68.0  200   6  3   4.9   2.7 |  21.5  70.7  215   4  2  10.5   5.7
  6250  20.3  68.5  190   5  3   4.9   2.7 |  22.3  72.1  215   3  2  10.3   5.6
  6000  20.7  69.3  180   5  2   5.7   3.1 |  23.0  73.4  215   3  2  10.3   5.7
  5750  21.2  70.2  175   5  2  10.4   5.7 |  23.9  75.0  215   4  2  15.7   8.6
  5500  22.2  72.0  175   4  2  15.4   8.5 |  25.4  77.7  220   4  2  24.5  13.4
  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

           07/20/2016 at 1500 MDT          |       07/20/2016 at 1800 MDT
                                           |
K index... +31.1  LI... +270.7             | K index... +27.3  LI... +270.4
CAPE... +276.0  CIN... -40.6               | CAPE... +340.2  CIN... -55.9
                                           |
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 -65.8 -86.4  205  22 11   1.0   0.5 | -65.8 -86.4  220  23 12   1.9   1.1
 45000 -61.3 -78.3  210  25 13   5.8   3.2 | -61.0 -77.8  210  23 12   5.2   2.9
 40000 -51.6 -60.9  215  21 11   9.0   4.9 | -51.5 -60.7  185  22 11   8.9   4.9
 38000 -46.2 -51.2  215  22 11   9.0   4.9 | -46.1 -51.0  190  22 11   8.9   4.9
 36000 -40.9 -41.6  215  23 12   8.6   4.7 | -40.8 -41.4  200  22 12   8.3   4.6
 34000 -35.8 -32.4  215  23 12   8.5   4.7 | -35.7 -32.3  205  23 12   8.4   4.6
 32000 -30.6 -23.1  220  22 11   9.3   5.1 | -30.7 -23.3  215  23 12   9.1   5.0
 30000 -25.5 -13.9  225  19 10   7.8   4.3 | -25.9 -14.6  220  20 10   8.0   4.4
 29000 -23.2  -9.8  230  18  9   7.8   4.3 | -23.5 -10.3  225  19 10   8.1   4.4
 28000 -21.0  -5.8  230  18  9   6.6   3.6 | -21.3  -6.3  225  18  9   6.5   3.6
 27000 -19.1  -2.4  230  17  9   6.6   3.6 | -19.4  -2.9  230  17  9   6.6   3.6
 26000 -17.2   1.0  230  17  9   6.6   3.6 | -17.4   0.7  235  16  8   6.7   3.7
 25000 -15.3   4.5  230  16  8   6.3   3.4 | -15.5   4.1  240  15  8   6.3   3.5
 24000 -13.4   7.9  235  16  8   6.2   3.4 | -13.7   7.3  245  14  7   6.1   3.3
 23000 -11.6  11.1  235  15  8   6.3   3.4 | -11.9  10.6  250  13  7   6.1   3.4
 22000  -9.8  14.4  235  15  8   5.6   3.1 |  -9.7  14.5  260  13  7   5.4   3.0
 21000  -8.3  17.1  240  14  7   5.4   3.0 |  -8.1  17.4  265  13  7   5.5   3.0
 20000  -6.7  19.9  240  14  7   5.4   3.0 |  -6.5  20.3  270  13  7   5.5   3.0
 19500  -5.9  21.4  245  14  7   5.4   3.0 |  -5.7  21.7  270  13  7   5.5   3.0
 19000  -5.2  22.6  245  14  7   5.2   2.9 |  -4.9  23.2  275  13  7   5.4   3.0
 18500  -4.4  24.1  245  14  7   5.2   2.9 |  -4.1  24.6  275  13  7   5.4   3.0
 18000  -3.3  26.1  250  14  7   5.2   2.9 |  -3.3  26.1  275  13  7   6.2   3.4
 17500  -2.6  27.3  250  14  7   5.2   2.9 |  -2.4  27.7  275  13  6   6.1   3.4
 17000  -1.8  28.8  255  14  7   5.8   3.2 |  -1.5  29.3  275  12  6   6.7   3.7
 16500  -0.9  30.4  255  14  7   5.9   3.3 |  -0.4  31.3  275  12  6   7.0   3.9
 16000  -0.1  31.8  255  14  7   6.4   3.5 |   0.6  33.1  275  12  6   7.2   4.0
 15500   1.0  33.8  255  13  7   7.4   4.1 |   1.8  35.2  275  12  6   8.2   4.5
 15000   2.0  35.6  255  13  6   7.3   4.0 |   3.0  37.4  270  11  6   8.2   4.5
 14500   3.2  37.8  255  12  6   8.9   4.9 |   4.2  39.6  270  11  6   7.9   4.3
 14000   4.5  40.1  255  12  6   8.9   4.9 |   5.3  41.5  270  11  5   7.9   4.3
 13500   5.7  42.3  255  11  6   7.6   4.1 |   6.5  43.7  265  10  5   8.0   4.4
 13000   6.8  44.2  255  11  6   7.5   4.1 |   7.6  45.7  265  10  5   8.0   4.4
 12500   7.8  46.0  255  10  5   7.6   4.2 |   8.8  47.8  265  10  5   8.0   4.4
 12000   8.9  48.0  255  10  5   7.6   4.2 |   9.9  49.8  265   9  5   7.9   4.4
 11500  10.0  50.0  255   9  5   7.6   4.2 |  11.0  51.8  265   8  4   7.9   4.3
 11000  11.1  52.0  250   8  4   7.6   4.1 |  12.2  54.0  260   7  4   7.5   4.1
 10500  12.1  53.8  245   7  4   6.0   3.3 |  13.3  55.9  260   7  3   3.3   1.8
 10250  12.5  54.5  245   7  4   6.9   3.8 |  13.4  56.1  255   7  3   5.3   2.9
 10000  13.2  55.8  240   7  3   9.1   5.0 |  14.2  57.6  255   6  3  12.3   6.8
  9750  13.8  56.8  240   6  3   8.5   4.7 |  15.0  59.0  255   6  3  11.2   6.1
  9500  14.4  57.9  235   6  3   7.7   4.2 |  15.8  60.4  250   5  3   8.6   4.7
  9250  14.9  58.8  230   5  3   7.0   3.8 |  16.2  61.2  250   5  3   5.9   3.3
  9000  15.4  59.7  225   5  3   7.8   4.3 |  16.8  62.2  250   5  2   8.9   4.9
  8750  16.0  60.8  220   5  3   8.1   4.5 |  17.4  63.3  245   4  2   9.9   5.4
  8500  16.6  61.9  215   5  2   8.1   4.4 |  18.1  64.6  240   4  2   8.4   4.6
  8250  17.1  62.8  210   4  2   8.0   4.4 |  18.7  65.7  230   3  2   7.4   4.1
  8000  17.7  63.9  205   4  2   8.2   4.5 |  19.2  66.6  220   3  2   8.2   4.5
  7750  18.3  64.9  205   4  2   8.4   4.6 |  19.8  67.6  205   3  1   8.5   4.6
  7500  19.0  66.2  200   3  2   8.4   4.6 |  20.4  68.7  190   2  1   7.2   4.0
  7250  19.6  67.3  200   3  2   8.5   4.7 |  20.8  69.4  175   2  1   6.6   3.6
  7000  20.2  68.4  200   3  1   8.1   4.4 |  21.3  70.3  155   2  1   6.8   3.8
  6750  20.7  69.3  195   2  1   9.1   5.0 |  21.8  71.2  135   2  1   7.9   4.3
  6500  21.4  70.5  195   2  1  10.2   5.6 |  22.4  72.3  130   2  1   8.8   4.8
  6250  22.2  72.0  195   2  1  10.0   5.5 |  23.1  73.6  125   2  1   8.5   4.6
  6000  22.9  73.2  200   2  1   9.8   5.4 |  23.7  74.7  125   2  1   9.3   5.1
  5750  23.7  74.7  200   2  1  12.3   6.8 |  24.5  76.1  120   2  1  12.9   7.1
  5500  24.8  76.6  205   2  1  17.2   9.5 |  25.6  78.1  120   2  1  16.4   9.0
  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
________________________________________________________________________________

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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