Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 211210
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0610 MDT Sunday, October 21, 2018

This forecast is for Sunday, October 21, 2018:

If the trigger temperature of 69.1 F/20.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 218 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8299 ft MSL (3460 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1415 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................. 7277 ft MSL (2438 ft AGL)
Thermal soaring outlook for Monday 10/22....... Fair

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

Remarks...

***ATTENTION Soaring Forecast Users***The National Weather Service in Boulder wants to hear from you.
Please send and email to paul.t.schlatter@noaa.gov and let us know how you use the Soaring Forecast.  Thanks!

Sunrise/Sunset.................... 07:30:14 / 18:27:09 MDT
Total possible sunshine........... 10 hr 56 min 55 sec (656 min 55 sec)
Altitude of sun at 12:58:41 MDT... 40.00 degrees

Upper air data from rawinsonde observation taken on 10/21/2018 at 0600 MDT

Freezing level.................. 12219 ft MSL (7380 ft AGL)
Convective condensation level... 17997 ft MSL (13158 ft AGL)
Lifted condensation level....... 14456 ft MSL (9617 ft AGL)
Lifted index.................... +3.9
K index......................... +24.0

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -64.1 -83.4   230   38   20   2.9   1.6   91.8 197.2    41.1      M    M
 45000  -59.4 -74.9   235   47   24   3.0   1.6   75.0 166.9    33.8      M    M
 40000  -56.2 -69.2   210   35   18   5.3   2.9   57.1 134.9    24.4      M    M
 38000  -53.5 -64.3   220   31   16   0.7   0.4   52.4 126.3    21.9      M    M
 36000  -51.3 -60.3   210   22   12   6.1   3.3   45.9 114.7    18.0      M    M
 34000  -48.7 -55.7   210   24   12   2.4   1.3   41.3 106.3    15.2      M    M
 32000  -44.8 -48.6   210   28   14   7.9   4.3   38.6 101.5    13.6      M    M
 30000  -40.2 -40.4   215   31   16   9.2   5.0   36.9  98.5    12.7      M    M
 29000  -37.6 -35.7   215   33   17   6.6   3.6   36.5  97.7    12.6      M    M
 28000  -36.0 -32.8   215   31   16   5.2   2.9   34.8  94.6    11.3      M    M
 27000  -33.8 -28.8   215   28   14   7.7   4.2   33.7  92.7    10.7      M    M
 26000  -31.5 -24.7   215   26   13   7.7   4.2   32.9  91.3    10.2      M    M
 25000  -29.2 -20.6   215   23   12   7.3   4.0   32.3  90.1     9.8      M    M
 24000  -26.4 -15.5   215   18    9   9.2   5.1   32.1  89.7     9.7      M    M
 23000  -23.7 -10.7   210   14    7   9.2   5.1   31.9  89.5     9.7      M    M
 22000  -20.9  -5.6   215   12    6   8.7   4.8   31.7  89.1     9.6      M    M
 21000  -18.6  -1.5   230   10    5   7.5   4.1   30.9  87.6     9.0      M    M
 20000  -16.4   2.5   245    9    5   8.6   4.7   30.2  86.3     8.5      M    M
 19500  -15.0   5.0   245   10    5   9.3   5.1   30.1  86.1     8.5      M    M
 19000  -12.9   8.8   250   11    6   9.5   5.2   30.0  85.9     8.4      M    M
 18500  -11.5  11.3   250   11    6   9.5   5.2   29.9  85.8     8.4      M    M
 18000  -10.0  14.0   255   11    5   9.5   5.2   29.8  85.7     8.4      M    M
 17500   -8.6  16.5   255   10    5   9.5   5.2   29.8  85.6     8.5      M    M
 17000   -7.2  19.0   255   10    5  10.0   5.5   29.8  85.6     8.5      M    M
 16500   -6.1  21.0   260   10    5   6.1   3.3   29.4  84.8     8.1      M    M
 16000   -5.2  22.6   260   10    5   3.2   1.7   28.6  83.5     7.6      M    M
 15500   -5.0  23.0   245   12    6 -10.3  -5.7   27.2  81.0     6.4      M    M
 15000   -6.5  20.3   240   14    7   2.4   1.3   24.3  75.8     3.5      M    M
 14500   -6.1  21.0   250   18    9   7.7   4.2   23.3  74.0     2.4      M    M
 14000   -4.8  23.4   255   22   11   9.2   5.0   23.1  73.7     2.3      M    M
 13500   -3.4  25.9   255   20   10   9.1   5.0   23.0  73.4     2.2      M    M
 13000   -2.1  28.2   255   18    9   9.1   5.0   22.9  73.2     2.1      M    M
 12500   -0.7  30.7   255   16    8   9.1   5.0   22.8  73.1     2.0      M    M
 12000    0.6  33.1   255   14    7   9.1   5.0   22.8  73.0     2.0      M    M
 11500    2.0  35.6   250   12    6   9.1   5.0   22.6  72.8     1.8      M    M
 11000    3.4  38.1   245   10    5   9.2   5.0   22.5  72.6     1.8      M    M
 10500    4.7  40.5   225   12    6  10.0   5.5   22.4  72.3     1.6      M    M
 10250    5.5  41.9   215   13    7   9.7   5.3   22.5  72.4     1.7      M    M
 10000    6.1  43.0   215   14    7   7.2   4.0   22.3  72.2     1.6      M    M
  9750    6.7  44.1   210   15    8   6.8   3.7   22.1  71.8     1.4      M    M
  9500    7.2  45.0   205   15    8   6.9   3.8   21.9  71.4     1.2      M    M
  9250    7.7  45.9   205   16    8   6.9   3.8   21.7  71.0     0.9      M    M
  9000    8.2  46.8   200   17    9   6.8   3.7   21.4  70.6     0.7      M    M
  8750    8.7  47.7   195   17    9   7.0   3.8   21.2  70.2     0.5      M    M
  8500    9.2  48.6   185   16    8   6.4   3.5   21.0  69.8     0.3      M    M
  8250    9.6  49.3   180   17    9   4.4   2.4   20.7  69.2    -0.0    217  1.1
  8000   10.0  50.0   170   17    9   5.8   3.2   20.3  68.5    -0.4    198  1.0
  7750   10.4  50.7   165   17    9  -0.3  -0.2   19.9  67.7    -0.7    179  0.9
  7500   10.0  50.0   160   18    9  -7.1  -3.9   18.7  65.6    -1.9    185  0.9
  7250    9.6  49.3   155   19   10  -0.3  -0.2   17.6  63.7    -2.9    187  1.0
  7000    9.8  49.6   150   20   10   3.3   1.8   17.0  62.7    -3.5    174  0.9
  6750   10.0  50.0   145   18    9   2.5   1.4   16.5  61.7    -4.0    160  0.8
  6500   10.4  50.7   140   16    8   7.2   3.9   16.1  60.9    -4.4    143  0.7
  6250   11.1  52.0   135   14    7  10.5   5.7   16.1  60.9    -4.5    114  0.6
  6000   11.8  53.2   130   12    6   9.1   5.0   16.1  60.9    -4.5     85  0.4
  5750   12.5  54.5   125   11    6  11.3   6.2   16.1  60.9    -4.5     56  0.3
  5500   13.2  55.8   120   10    5   3.6   2.0   16.1  60.9    -4.5     28  0.1
  5250   12.7  54.9   115   10    5 -16.8  -9.2   14.8  58.7    -5.8     36  0.2
  5000   10.8  51.4   110    9    4 -28.5 -15.6   12.3  54.1    -8.4     84  0.4

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

           10/21/2018 at 0900 MDT          |       10/21/2018 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +1.8        | CAPE...     0.0    LI...       +0.9
CINH...    -0.0    K Index... +23.4        | CINH...   -13.4    K Index... +24.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.6 -80.7  235  17  9   2.8   1.6 | -62.5 -80.5  235  18  9   3.0   1.7
 45000 -58.5 -73.3  230  22 11   2.1   1.1 | -58.1 -72.6  230  23 12   2.2   1.2
 40000 -55.4 -67.7  225  22 11   2.0   1.1 | -54.8 -66.6  230  25 13   2.2   1.2
 38000 -53.8 -64.8  220  20 10   2.9   1.6 | -53.1 -63.6  225  23 12   2.6   1.4
 36000 -51.9 -61.4  220  17  9   2.9   1.6 | -51.5 -60.7  225  20 10   2.6   1.4
 34000 -48.9 -56.0  215  15  8   6.7   3.7 | -48.8 -55.8  220  17  9   6.3   3.5
 32000 -44.9 -48.8  215  14  7   6.7   3.7 | -45.0 -49.0  220  14  7   6.3   3.5
 30000 -40.5 -40.9  220  14  7   7.9   4.3 | -40.8 -41.4  220  13  6   7.7   4.2
 29000 -38.1 -36.6  220  13  7   7.9   4.3 | -38.4 -37.1  220  12  6   7.7   4.2
 28000 -35.8 -32.4  220  13  7   7.9   4.3 | -36.1 -33.0  220  12  6   7.7   4.2
 27000 -33.5 -28.3  220  12  6   7.4   4.0 | -33.9 -29.0  225  12  6   7.5   4.1
 26000 -31.3 -24.3  220  11  6   7.4   4.0 | -31.6 -24.9  225  11  6   7.5   4.1
 25000 -29.1 -20.4  225  10  5   7.4   4.1 | -29.4 -20.9  225  11  6   7.5   4.1
 24000 -26.8 -16.2  225   9  5   8.5   4.7 | -27.0 -16.6  225  10  5   8.9   4.9
 23000 -24.2 -11.6  225   9  4   8.5   4.7 | -24.3 -11.7  220  10  5   8.8   4.8
 22000 -21.7  -7.1  225   8  4   8.5   4.7 | -21.0  -5.8  220   9  5   8.8   4.8
 21000 -18.4  -1.1  230   7  4   8.8   4.8 | -18.5  -1.3  215   9  4   8.6   4.7
 20000 -15.8   3.6  230   6  3   8.8   4.9 | -15.9   3.4  215   8  4   8.6   4.7
 19500 -14.4   6.1  230   6  3   8.9   4.9 | -14.6   5.7  215   7  4   8.6   4.7
 19000 -13.2   8.2  230   5  3   7.9   4.4 | -13.4   7.9  210   7  3   8.1   4.5
 18500 -12.0  10.4  230   5  3   7.8   4.3 | -12.2  10.0  210   6  3   8.1   4.4
 18000 -10.8  12.6  230   5  2   7.3   4.0 | -11.0  12.2  210   6  3   7.8   4.3
 17500  -9.9  14.2  230   5  2   6.0   3.3 |  -9.9  14.2  215   6  3   7.0   3.8
 17000  -9.1  15.6  230   5  3   6.3   3.4 |  -8.9  16.0  215   6  3   7.3   4.0
 16500  -8.3  17.1  230   5  3   4.3   2.4 |  -8.0  17.6  220   6  3   4.9   2.7
 16000  -7.7  18.1  235   5  3   4.5   2.5 |  -7.3  18.9  220   5  3   5.0   2.8
 15500  -7.1  19.2  235   6  3   5.8   3.2 |  -6.6  20.1  220   5  3   5.8   3.2
 15000  -6.2  20.8  235   6  3   6.4   3.5 |  -5.7  21.7  220   5  3   6.2   3.4
 14500  -5.3  22.5  240   6  3   6.6   3.6 |  -4.9  23.2  220   5  3   6.4   3.5
 14000  -4.3  24.3  235   6  3   6.9   3.8 |  -4.0  24.8  220   5  3   6.6   3.6
 13500  -3.3  26.1  235   6  3   7.0   3.9 |  -3.0  26.6  215   5  3   6.7   3.7
 13000  -2.3  27.9  235   6  3   7.3   4.0 |  -2.0  28.4  215   5  3   7.1   3.9
 12500  -1.2  29.8  230   6  3   7.4   4.0 |  -1.0  30.2  215   5  3   7.2   3.9
 12000  -0.1  31.8  230   6  3   7.7   4.2 |   0.1  32.2  220   5  3   7.4   4.1
 11500   1.1  34.0  230   6  3   7.7   4.2 |   1.2  34.2  220   6  3   7.4   4.1
 11000   2.2  36.0  225   6  3   7.9   4.3 |   2.3  36.1  220   6  3   7.5   4.1
 10500   3.4  38.1  225   7  3   7.5   4.1 |   3.4  38.1  220   6  3   7.4   4.0
 10250   3.9  39.0  225   6  3   6.0   3.3 |   3.9  39.0  220   6  3   6.6   3.6
 10000   4.4  39.9  225   6  3   6.8   3.8 |   4.4  39.9  220   6  3   7.0   3.8
  9750   5.0  41.0  220   6  3   8.2   4.5 |   5.0  41.0  215   6  3   7.5   4.1
  9500   5.5  41.9  215   6  3   7.6   4.2 |   5.5  41.9  215   6  3   7.4   4.1
  9250   6.1  43.0  215   6  3   7.4   4.1 |   6.1  43.0  215   5  3   7.9   4.3
  9000   6.7  44.1  215   6  3   7.0   3.8 |   6.7  44.1  215   5  3   7.4   4.1
  8750   7.2  45.0  210   6  3   6.4   3.5 |   7.2  45.0  210   5  3   6.4   3.5
  8500   7.6  45.7  205   6  3   6.4   3.5 |   7.7  45.9  210   5  2   6.8   3.8
  8250   8.1  46.6  200   6  3   6.5   3.6 |   8.2  46.8  205   4  2   7.2   4.0
  8000   8.6  47.5  195   5  3   6.3   3.5 |   8.8  47.8  200   4  2   7.5   4.1
  7750   9.1  48.4  190   5  3   5.3   2.9 |   9.4  48.9  195   4  2   8.5   4.7
  7500   9.5  49.1  185   5  3   5.2   2.8 |  10.0  50.0  190   3  2   7.8   4.3
  7250   9.9  49.8  175   5  2   5.6   3.0 |  10.6  51.1  185   3  2   6.7   3.7
  7000  10.3  50.5  170   5  2   5.6   3.1 |  11.1  52.0  175   3  2   7.4   4.0
  6750  10.7  51.3  160   4  2   2.7   1.5 |  11.7  53.1  170   3  2   8.5   4.6
  6500  10.7  51.3  155   4  2   1.4   0.8 |  12.3  54.1  175   3  1   7.5   4.1
  6250  10.9  51.6  150   4  2   2.7   1.5 |  12.8  55.0  170   2  1   6.5   3.6
  6000  11.1  52.0  140   3  2   2.1   1.2 |  13.3  55.9  170   2  1   6.5   3.6
  5750  11.1  52.0  130   4  2  -3.1  -1.7 |  13.9  57.0  155   3  1   9.9   5.4
  5500  10.0  50.0  095   3  1   2.8   1.6 |  15.8  60.4  155   2  1   4.5   2.5
  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

           10/21/2018 at 1500 MDT          |       10/21/2018 at 1800 MDT
                                           |
CAPE...   +70.8    LI...       +0.5        | CAPE...   +76.1    LI...       -0.2
CINH...   -20.0    K Index... +23.6        | CINH...   -78.6    K Index... +20.2
                                           |
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 -62.7 -80.9  240  20 10   2.4   1.3 | -62.3 -80.1  245  19 10   2.1   1.1
 45000 -59.1 -74.4  240  25 13   2.4   1.3 | -59.1 -74.4  240  23 12   1.7   1.0
 40000 -55.5 -67.9  235  28 14   2.4   1.3 | -56.5 -69.7  240  25 13   1.7   0.9
 38000 -53.5 -64.3  235  26 13   3.5   1.9 | -54.4 -65.9  240  24 12   4.0   2.2
 36000 -51.4 -60.5  235  23 12   3.5   1.9 | -52.0 -61.6  245  22 12   4.0   2.2
 34000 -48.4 -55.1  235  20 10   5.6   3.1 | -48.6 -55.5  245  20 10   6.2   3.4
 32000 -45.0 -49.0  230  15  8   5.6   3.1 | -44.9 -48.8  240  17  9   6.2   3.4
 30000 -41.0 -41.8  230  13  7   7.7   4.2 | -40.7 -41.3  240  15  8   7.8   4.3
 29000 -38.7 -37.7  230  13  7   7.7   4.2 | -38.4 -37.1  240  14  7   7.8   4.3
 28000 -36.4 -33.5  230  12  6   7.7   4.2 | -36.0 -32.8  240  13  7   7.8   4.3
 27000 -34.1 -29.4  225  12  6   7.8   4.3 | -33.7 -28.7  235  13  7   7.8   4.3
 26000 -31.7 -25.1  225  12  6   7.8   4.3 | -31.4 -24.5  235  12  6   7.8   4.3
 25000 -29.4 -20.9  225  12  6   7.9   4.3 | -29.1 -20.4  230  12  6   7.8   4.3
 24000 -26.9 -16.4  220  11  6   8.8   4.8 | -26.7 -16.1  230  12  6   7.9   4.4
 23000 -24.3 -11.7  220  11  6   8.8   4.8 | -24.4 -11.9  225  12  6   7.9   4.4
 22000 -21.7  -7.1  220  10  5   8.8   4.8 | -22.0  -7.6  225  11  6   8.0   4.4
 21000 -19.1  -2.4  220  10  5   8.6   4.7 | -19.5  -3.1  225  11  6   8.7   4.8
 20000 -15.9   3.4  220   9  5   8.6   4.7 | -16.3   2.7  225  10  5   8.7   4.8
 19500 -14.6   5.7  220   9  4   8.6   4.7 | -15.0   5.0  225   9  5   8.7   4.8
 19000 -13.4   7.9  220   8  4   7.9   4.3 | -13.7   7.3  225   9  5   8.4   4.6
 18500 -12.2  10.0  220   8  4   7.8   4.3 | -12.4   9.7  230   8  4   8.3   4.6
 18000 -11.1  12.0  215   8  4   7.6   4.2 | -11.2  11.8  230   8  4   8.2   4.5
 17500 -10.0  14.0  215   8  4   6.8   3.7 | -10.0  14.0  230   8  4   7.5   4.1
 17000  -9.1  15.6  215   7  4   7.0   3.8 |  -8.9  16.0  230   7  4   7.6   4.2
 16500  -8.1  17.4  215   7  4   6.1   3.4 |  -7.9  17.8  225   7  4   6.8   3.7
 16000  -7.2  19.0  215   7  4   6.1   3.4 |  -6.9  19.6  225   7  4   6.8   3.7
 15500  -6.4  20.5  210   7  3   6.4   3.5 |  -5.9  21.4  225   7  4   6.6   3.6
 15000  -5.5  22.1  210   7  3   6.5   3.6 |  -5.0  23.0  220   7  4   6.5   3.6
 14500  -4.5  23.9  210   6  3   6.8   3.7 |  -4.1  24.6  215   8  4   6.7   3.7
 14000  -3.5  25.7  210   6  3   7.3   4.0 |  -3.1  26.4  210   7  4   7.5   4.1
 13500  -2.5  27.5  210   6  3   7.3   4.0 |  -2.0  28.4  210   7  4   7.5   4.1
 13000  -1.4  29.5  210   6  3   7.5   4.1 |  -1.0  30.2  205   7  3   7.6   4.2
 12500  -0.3  31.5  210   5  3   7.6   4.1 |   0.1  32.2  200   6  3   7.6   4.2
 12000   0.7  33.3  210   5  3   7.2   4.0 |   1.2  34.2  200   6  3   8.0   4.4
 11500   1.8  35.2  210   5  3   7.2   4.0 |   2.4  36.3  195   5  3   7.9   4.3
 11000   2.9  37.2  210   5  3   7.7   4.2 |   3.6  38.5  195   5  2   8.4   4.6
 10500   4.0  39.2  210   5  2   7.4   4.0 |   4.8  40.6  190   4  2   8.4   4.6
 10250   4.5  40.1  210   4  2   6.4   3.5 |   5.4  41.7  190   4  2   6.7   3.7
 10000   5.0  41.0  210   4  2   8.2   4.5 |   5.9  42.6  185   3  2   7.5   4.1
  9750   5.7  42.3  215   4  2   9.9   5.5 |   6.5  43.7  185   3  2   9.3   5.1
  9500   6.4  43.5  215   3  2   9.3   5.1 |   7.2  45.0  185   3  1   8.8   4.8
  9250   7.1  44.8  215   3  2   7.9   4.3 |   7.9  46.2  180   2  1   9.0   4.9
  9000   7.7  45.9  220   3  1   8.3   4.6 |   8.5  47.3  175   2  1   8.2   4.5
  8750   8.4  47.1  220   2  1   9.7   5.3 |   9.1  48.4  175   2  1   7.6   4.2
  8500   9.1  48.4  225   2  1   9.0   4.9 |   9.7  49.5  175   1  1   7.8   4.3
  8250   9.7  49.5  230   2  1   8.0   4.4 |  10.2  50.4  165   1  0   7.5   4.1
  8000  10.3  50.5  235   1  1   8.3   4.5 |  10.8  51.4  135   1  0   8.0   4.4
  7750  11.0  51.8  240   1  1   9.9   5.4 |  11.4  52.5  000   0  0   9.5   5.2
  7500  11.7  53.1  240   1  1   9.0   4.9 |  12.1  53.8  000   0  0   8.7   4.8
  7250  12.3  54.1  250   1  1   7.6   4.1 |  12.7  54.9  025   1  0   7.3   4.0
  7000  12.9  55.2  265   1  0   8.0   4.4 |  13.3  55.9  025   1  1   7.6   4.2
  6750  13.5  56.3  270   1  0   9.3   5.1 |  13.9  57.0  025   1  1   9.5   5.2
  6500  14.3  57.7  260   1  0   9.5   5.2 |  14.7  58.5  015   1  1   9.5   5.2
  6250  15.0  59.0  270   1  0   9.1   5.0 |  15.3  59.5  010   1  1   7.9   4.4
  6000  15.6  60.1  285   1  0   8.4   4.6 |  15.9  60.6  010   1  1   8.7   4.8
  5750  16.3  61.3  275   1  0  11.6   6.4 |  16.5  61.7  005   1  1   6.2   3.4
  5500  18.6  65.5  300   1  0   5.0   2.8 |  17.0  62.6  355   1  1  11.4   6.2
  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
________________________________________________________________________________

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.

CINH (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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