Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201240
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0640 MDT Saturday, April 20, 2019

This forecast is for Saturday, April 20, 2019:

If the trigger temperature of 74.9 F/23.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 350 ft/min (1.8 m/s)
   Maximum height of thermals.................. 9701 ft MSL (4862 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1300 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7030 ft MSL (2191 ft AGL)
Thermal soaring outlook for Sunday 04/21....... Good

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.................... 06:30:06 / 19:55:58 MDT
Total possible sunshine........... 13 hr 25 min 52 sec (805 min 52 sec)
Altitude of sun at 13:13:02 MDT... 62.34 degrees

Upper air data from rawinsonde observation taken on 04/20/2019 at 0600 MDT

Freezing level.................. 13304 ft MSL (8465 ft AGL)
Convective condensation level... 19708 ft MSL (14869 ft AGL)
Lifted condensation level....... 18331 ft MSL (13492 ft AGL)
Lifted index.................... +1.0
K index......................... +6.7

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  -63.2 -81.8   275   32   17   4.8   2.6   93.6 200.5    39.6      M    M
 45000  -55.3 -67.5   255   43   22   2.9   1.6   81.1 177.9    34.8      M    M
 40000  -56.5 -69.7   245   39   20  -1.5  -0.8   56.4 133.6    21.0      M    M
 38000  -55.3 -67.5   230   40   21   4.1   2.2   49.4 121.0    16.9      M    M
 36000  -52.9 -63.2   235   42   22   3.8   2.1   44.3 111.7    13.7      M    M
 34000  -49.3 -56.7   230   45   23   6.2   3.4   41.1 105.9    11.9      M    M
 32000  -44.5 -48.1   230   38   19   9.0   4.9   38.6 101.5    10.4      M    M
 30000  -39.4 -38.9   230   32   16   7.6   4.1   37.7  99.8     9.9      M    M
 29000  -37.3 -35.1   230   29   15   2.7   1.5   36.6  97.9     9.2      M    M
 28000  -35.8 -32.4   225   26   13   8.9   4.9   34.8  94.6     7.9      M    M
 27000  -33.1 -27.6   225   28   15   8.8   4.9   34.4  93.9     7.7      M    M
 26000  -30.7 -23.3   230   31   16   8.2   4.5   33.8  92.9     7.4      M    M
 25000  -28.3 -18.9   230   33   17   7.7   4.2   33.2  91.8     6.9      M    M
 24000  -26.8 -16.2   220   33   17  -2.5  -1.4   31.4  88.6     5.6      M    M
 23000  -25.6 -14.1   225   30   16   8.9   4.9   29.3  84.8     3.9      M    M
 22000  -22.8  -9.0   230   28   14   9.0   4.9   29.0  84.3     3.8      M    M
 21000  -20.1  -4.2   240   26   13   9.0   4.9   28.7  83.7     3.6      M    M
 20000  -17.4   0.7   250   24   12   9.0   4.9   28.5  83.4     3.5      M    M
 19500  -16.0   3.2   250   25   13   9.0   4.9   28.4  83.1     3.4      M    M
 19000  -14.7   5.5   250   26   13   8.9   4.9   28.2  82.8     3.3      M    M
 18500  -13.4   7.9   250   28   14   8.3   4.6   28.0  82.5     3.1      M    M
 18000  -11.7  10.9   245   33   17   7.9   4.3   27.6  81.6     2.6      M    M
 17500  -10.5  13.1   240   36   19   7.7   4.2   27.3  81.1     2.3      M    M
 17000   -9.4  15.1   240   39   20   3.9   2.2   27.0  80.6     2.0      M    M
 16500   -8.7  16.3   235   37   19   9.9   5.5   26.2  79.2     1.3      M    M
 16000   -7.3  18.9   235   35   18   8.7   4.8   26.0  78.9     1.2      M    M
 15500   -6.0  21.2   235   33   17   9.5   5.2   25.9  78.6     1.0      M    M
 15000   -4.6  23.7   235   31   16   9.4   5.2   25.8  78.5     1.0      M    M
 14500   -3.2  26.2   235   30   15   9.4   5.2   25.8  78.4     0.9      M    M
 14000   -1.8  28.8   235   28   14   9.0   4.9   25.7  78.3     0.9      M    M
 13500   -0.4  31.3   235   26   13   9.0   4.9   25.6  78.1     0.8      M    M
 13000    1.0  33.8   235   23   12   9.0   4.9   25.5  77.9     0.7      M    M
 12500    2.3  36.1   230   21   11   9.0   4.9   25.4  77.7     0.6      M    M
 12000    3.7  38.7   230   19   10   9.0   4.9   25.3  77.5     0.5      M    M
 11500    5.0  41.0   230   18    9   9.0   4.9   25.1  77.2     0.4      M    M
 11000    6.3  43.3   230   17    9   9.0   4.9   25.0  77.0     0.3      M    M
 10500    7.7  45.9   230   17    9   9.0   5.0   24.9  76.8     0.2      M    M
 10250    8.4  47.1   230   16    8   9.0   4.9   24.8  76.7     0.1      M    M
 10000    9.0  48.2   230   15    8   9.0   5.0   24.8  76.6     0.1      M    M
  9750    9.7  49.5   230   14    7   8.9   4.9   24.7  76.5     0.0      M    M
  9500   10.4  50.7   230   13    7   7.9   4.3   24.6  76.3    -0.1    330  1.7
  9250   10.9  51.6   235   11    6   7.3   4.0   24.5  76.0    -0.2    307  1.6
  9000   11.5  52.7   235   10    5   7.4   4.1   24.3  75.7    -0.4    283  1.4
  8750   12.0  53.6   235    9    5   7.4   4.1   24.1  75.4    -0.6    259  1.3
  8500   12.5  54.5   230    8    4   7.4   4.1   23.9  75.0    -0.8    235  1.2
  8250   13.1  55.6   225    6    3   7.5   4.1   23.7  74.7    -1.0    212  1.1
  8000   13.6  56.5   220    5    3   7.1   3.9   23.6  74.4    -1.2    188  1.0
  7750   14.1  57.4   195    6    3   4.7   2.6   23.3  73.9    -1.5    167  0.8
  7500   14.3  57.7   180    7    4   3.2   1.7   22.8  73.0    -2.0    153  0.8
  7250   14.5  58.1   170    9    5   3.6   2.0   22.3  72.2    -2.5    138  0.7
  7000   14.8  58.6   160   11    6   3.4   1.9   21.8  71.3    -3.0    124  0.6
  6750   15.0  59.0   155   13    7   3.9   2.2   21.4  70.5    -3.5    109  0.6
  6500   14.8  58.6   155   15    8 -14.4  -7.9   20.5  68.9    -4.4    107  0.5
  6250   13.4  56.1   150   17    9  -7.8  -4.3   18.3  65.0    -6.5    143  0.7
  6000   13.9  57.0   150   19   10   7.6   4.1   18.0  64.5    -6.8    122  0.6
  5750   14.0  57.2   145   18    9  -1.2  -0.6   17.4  63.3    -7.5    112  0.6
  5500   13.9  57.0   145   15    8  -0.7  -0.4   16.6  61.9    -8.3    106  0.5
  5250   13.9  57.0   135   12    6   0.9   0.5   15.8  60.5    -9.1    100  0.5
  5000   13.8  56.8   125   10    5  -5.9  -3.2   15.1  59.1    -9.9     94  0.5

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

           04/20/2019 at 0900 MDT          |       04/20/2019 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +1.7        | CAPE...   +12.6    LI...       +0.3
CINH...    -1.6    K Index...  +8.5        | CINH...   -15.3    K Index... +16.0
                                           |
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 -59.5 -75.1  255  13  7   3.8   2.1 | -58.5 -73.3  245  14  7   4.0   2.2
 45000 -54.2 -65.6  245  16  8  -0.1  -0.1 | -53.0 -63.4  240  18  9   0.7   0.4
 40000 -54.5 -66.1  230  18  9  -0.2  -0.1 | -52.2 -62.0  225  20 10   0.6   0.3
 38000 -53.3 -63.9  225  19 10   3.1   1.7 | -51.7 -61.1  215  20 10   1.0   0.6
 36000 -51.5 -60.7  220  19 10   3.1   1.7 | -51.1 -60.0  210  20 10   1.0   0.6
 34000 -48.7 -55.7  220  19 10   5.9   3.2 | -49.4 -56.9  205  20 10   5.5   3.0
 32000 -45.2 -49.4  215  19 10   5.9   3.2 | -46.2 -51.2  205  21 11   5.4   3.0
 30000 -41.4 -42.5  210  18  9   7.1   3.9 | -42.5 -44.5  205  21 11   7.4   4.1
 29000 -39.3 -38.7  210  18  9   7.1   3.9 | -40.3 -40.5  205  21 11   7.4   4.1
 28000 -37.2 -35.0  210  18  9   7.1   3.9 | -38.1 -36.6  205  21 11   7.4   4.1
 27000 -35.0 -31.0  210  17  9   7.4   4.1 | -35.8 -32.4  210  21 11   8.2   4.5
 26000 -32.8 -27.0  210  17  9   7.4   4.1 | -33.4 -28.1  210  20 10   8.2   4.5
 25000 -30.6 -23.1  215  16  8   7.4   4.1 | -31.0 -23.8  210  18 10   8.2   4.5
 24000 -28.4 -19.1  215  15  8   7.8   4.3 | -28.5 -19.3  210  17  9   7.6   4.2
 23000 -26.0 -14.8  220  15  8   7.9   4.3 | -26.3 -15.3  210  16  8   7.4   4.1
 22000 -23.6 -10.5  220  14  7   7.9   4.3 | -24.1 -11.4  210  16  8   7.4   4.1
 21000 -21.2  -6.2  225  14  7   8.3   4.6 | -21.9  -7.4  210  15  8   8.2   4.5
 20000 -18.2  -0.8  225  14  7   8.3   4.6 | -18.9  -2.0  215  14  7   8.1   4.5
 19500 -16.9   1.6  230  14  7   8.3   4.6 | -17.7   0.1  215  14  7   8.1   4.5
 19000 -15.7   3.7  230  14  7   8.4   4.6 | -16.5   2.3  215  14  7   8.2   4.5
 18500 -14.4   6.1  230  14  7   8.6   4.7 | -15.2   4.6  220  14  7   8.6   4.7
 18000 -13.2   8.2  230  14  7   8.6   4.7 | -14.0   6.8  220  13  7   8.6   4.7
 17500 -11.9  10.6  230  14  7   8.9   4.9 | -12.7   9.1  220  13  7   8.8   4.8
 17000 -10.6  12.9  230  14  7   8.9   4.9 | -11.4  11.5  220  13  6   8.9   4.9
 16500  -9.3  15.3  230  14  7   9.0   4.9 | -10.0  14.0  220  12  6   9.0   4.9
 16000  -7.9  17.8  230  13  7   9.1   5.0 |  -8.7  16.3  220  12  6   9.3   5.1
 15500  -6.5  20.3  230  13  7   9.1   5.0 |  -7.3  18.9  220  11  6   9.3   5.1
 15000  -5.2  22.6  225  13  6   8.9   4.9 |  -5.9  21.4  220  11  6   9.2   5.0
 14500  -3.9  25.0  225  12  6   8.9   4.9 |  -4.5  23.9  220  11  6   9.1   5.0
 14000  -2.6  27.3  225  12  6   8.8   4.8 |  -3.2  26.2  220  11  6   9.3   5.1
 13500  -1.3  29.7  225  11  6   8.9   4.9 |  -1.8  28.8  220  11  6   9.3   5.1
 13000   0.0  32.0  225  11  6   8.7   4.8 |  -0.4  31.3  220  11  6   9.2   5.0
 12500   1.3  34.3  225  11  6   8.7   4.8 |   1.0  33.8  220  11  5   9.1   5.0
 12000   2.6  36.7  225  10  5   8.4   4.6 |   2.3  36.1  220  10  5   8.8   4.8
 11500   3.9  39.0  225  10  5   8.4   4.6 |   3.6  38.5  215  10  5   8.7   4.8
 11000   5.1  41.2  225   9  5   7.0   3.8 |   4.9  40.8  215   9  5   7.8   4.3
 10500   6.1  43.0  220   8  4   5.4   3.0 |   6.0  42.8  210   9  5   6.4   3.5
 10250   6.5  43.7  220   8  4  10.5   5.8 |   6.5  43.7  210   9  4  10.4   5.7
 10000   7.5  45.5  220   8  4  11.3   6.2 |   7.5  45.5  210   8  4  11.5   6.3
  9750   8.1  46.6  215   8  4   6.5   3.6 |   8.1  46.6  205   8  4   8.1   4.4
  9500   8.7  47.7  215   8  4   8.1   4.5 |   8.8  47.8  205   8  4   9.4   5.2
  9250   9.2  48.6  210   7  4   6.4   3.5 |   9.4  48.9  205   8  4   7.4   4.1
  9000   9.7  49.5  210   7  4   6.3   3.5 |   9.9  49.8  200   7  4   7.7   4.2
  8750  10.2  50.4  205   7  4   7.6   4.2 |  10.6  51.1  200   7  4   9.6   5.3
  8500  10.7  51.3  200   7  4   7.2   3.9 |  11.3  52.3  195   7  4   9.2   5.1
  8250  11.3  52.3  195   7  4   7.8   4.3 |  12.0  53.6  195   7  4   8.8   4.8
  8000  11.9  53.4  195   7  4   7.0   3.8 |  12.6  54.7  190   7  3   7.9   4.3
  7750  12.3  54.1  190   7  4   4.6   2.5 |  13.2  55.8  190   6  3   7.8   4.3
  7500  12.6  54.7  180   7  3   3.8   2.1 |  13.8  56.8  185   6  3   8.0   4.4
  7250  12.9  55.2  175   7  3   4.6   2.5 |  14.4  57.9  185   6  3   7.5   4.1
  7000  13.2  55.8  170   7  3   5.0   2.7 |  14.9  58.8  180   6  3   7.2   3.9
  6750  13.5  56.3  165   7  3   3.0   1.7 |  15.5  59.9  175   6  3   8.3   4.6
  6500  13.6  56.5  155   6  3   1.8   1.0 |  16.1  61.0  175   5  3   9.1   5.0
  6250  13.8  56.8  150   6  3   2.0   1.1 |  16.8  62.2  175   5  2   9.4   5.2
  6000  13.9  57.0  145   5  3   2.3   1.2 |  17.5  63.5  175   4  2  10.6   5.8
  5750  13.9  57.0  120   3  2  -0.3  -0.2 |  18.2  64.8  175   4  2   7.1   3.9
  5500  14.4  57.9  110   3  2  23.0  12.6 |  20.7  69.3  170   3  2  62.4  34.3
  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

           04/20/2019 at 1500 MDT          |       04/20/2019 at 1800 MDT
                                           |
CAPE...  +390.6    LI...       -0.2        | CAPE...  +359.1    LI...       -0.4
CINH...   -17.9    K Index... +24.2        | CINH...   -35.1    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 -58.3 -72.9  240  13  7   4.2   2.3 | -57.7 -71.9  240  14  7   3.9   2.2
 45000 -52.2 -62.0  235  16  8   1.0   0.5 | -51.9 -61.4  235  15  8   1.0   0.5
 40000 -50.9 -59.6  230  20 10   0.9   0.5 | -50.4 -58.7  240  18  9   1.0   0.5
 38000 -50.7 -59.3  220  20 10   0.1   0.1 | -50.3 -58.5  235  17  9  -0.3  -0.2
 36000 -50.6 -59.1  210  21 11   0.1   0.1 | -50.5 -58.9  225  16  8  -0.3  -0.2
 34000 -49.8 -57.6  200  22 11   3.6   2.0 | -50.3 -58.5  210  15  8   3.4   1.9
 32000 -47.7 -53.9  200  21 11   3.6   2.0 | -48.2 -54.8  190  13  7   3.1   1.7
 30000 -44.4 -47.9  195  19 10   9.3   5.1 | -45.2 -49.4  180  13  7   9.1   5.0
 29000 -41.6 -42.9  200  18  9   9.3   5.1 | -42.4 -44.3  180  13  7   9.2   5.0
 28000 -38.8 -37.8  200  17  9   9.3   5.1 | -39.7 -39.5  185  13  7   9.2   5.0
 27000 -36.1 -33.0  200  16  8   8.5   4.6 | -37.0 -34.6  190  12  6   8.8   4.9
 26000 -33.6 -28.5  200  15  8   8.5   4.6 | -34.3 -29.7  195  13  6   8.8   4.8
 25000 -31.0 -23.8  200  15  8   8.5   4.6 | -31.7 -25.1  200  13  7   8.8   4.8
 24000 -28.5 -19.3  200  14  7   8.2   4.5 | -29.1 -20.4  205  13  7   8.6   4.7
 23000 -26.2 -15.2  200  14  7   8.0   4.4 | -26.6 -15.9  210  13  7   8.4   4.6
 22000 -23.8 -10.8  195  14  7   8.0   4.4 | -24.1 -11.4  215  13  7   8.4   4.6
 21000 -21.4  -6.5  195  14  7   7.9   4.3 | -21.7  -7.1  220  13  7   8.0   4.4
 20000 -19.1  -2.4  195  14  7   7.9   4.3 | -19.4  -2.9  220  13  7   7.9   4.3
 19500 -17.9  -0.2  190  14  7   7.9   4.4 | -18.2  -0.8  220  13  7   7.9   4.3
 19000 -16.2   2.8  190  13  7   7.9   4.3 | -16.4   2.5  220  13  7   7.9   4.4
 18500 -15.1   4.8  190  13  7   7.3   4.0 | -15.3   4.5  220  13  7   7.8   4.3
 18000 -14.0   6.8  195  13  7   7.3   4.0 | -14.1   6.6  220  13  7   7.9   4.3
 17500 -12.9   8.8  195  13  7   7.4   4.1 | -13.0   8.6  220  13  7   7.8   4.3
 17000 -11.8  10.8  195  13  6   7.4   4.1 | -11.8  10.8  220  13  7   7.8   4.3
 16500 -10.7  12.7  195  12  6   7.5   4.1 | -10.7  12.7  220  13  7   7.8   4.3
 16000  -9.6  14.7  200  12  6   7.4   4.1 |  -9.6  14.7  220  13  6   7.7   4.2
 15500  -8.5  16.7  200  12  6   7.4   4.0 |  -8.4  16.9  220  12  6   7.7   4.2
 15000  -7.3  18.9  200  11  6   8.8   4.9 |  -7.3  18.9  215  12  6   7.7   4.2
 14500  -6.0  21.2  205  11  6   8.7   4.8 |  -6.2  20.8  215  12  6   7.7   4.2
 14000  -4.7  23.5  205  11  6   9.1   5.0 |  -5.0  23.0  215  11  6   8.2   4.5
 13500  -3.3  26.1  210  11  5   9.2   5.0 |  -3.8  25.2  215  11  6   8.3   4.6
 13000  -2.0  28.4  210  11  5   9.4   5.1 |  -2.6  27.3  215  11  5   8.8   4.8
 12500  -0.5  31.1  215  10  5   9.4   5.2 |  -1.2  29.8  215  10  5   9.1   5.0
 12000   0.9  33.6  215  10  5   9.6   5.2 |   0.2  32.4  215  10  5   9.3   5.1
 11500   2.3  36.1  220  10  5   9.6   5.3 |   1.6  34.9  215   9  5   9.4   5.2
 11000   3.7  38.7  220  10  5   8.5   4.7 |   3.0  37.4  215   8  4   8.6   4.7
 10500   4.9  40.8  220  10  5   6.5   3.6 |   4.1  39.4  210   8  4   6.4   3.5
 10250   5.5  41.9  220  10  5  12.5   6.9 |   4.7  40.5  210   8  4  10.7   5.9
 10000   6.6  43.9  225  10  5  13.5   7.4 |   5.6  42.1  210   7  4  12.2   6.7
  9750   7.3  45.1  225  10  5   7.9   4.3 |   6.4  43.5  210   7  3   8.6   4.7
  9500   8.0  46.4  225  10  5  10.2   5.6 |   7.0  44.6  210   6  3   8.8   4.8
  9250   8.7  47.7  225  10  5   6.6   3.6 |   7.7  45.9  210   6  3   9.7   5.3
  9000   9.1  48.4  230  10  5   7.6   4.2 |   8.4  47.1  210   6  3   9.8   5.4
  8750   9.9  49.8  230   9  5  11.2   6.2 |   9.1  48.4  210   5  3   8.8   4.9
  8500  10.7  51.3  230   9  5  10.7   5.9 |   9.8  49.6  210   5  2   9.1   5.0
  8250  11.5  52.7  235   9  5   9.2   5.0 |  10.4  50.7  210   4  2   9.0   4.9
  8000  12.0  53.6  235   9  5   7.7   4.2 |  11.1  52.0  210   4  2   8.7   4.8
  7750  12.7  54.9  240   9  5   9.5   5.2 |  11.7  53.1  210   3  2   8.4   4.6
  7500  13.4  56.1  240   9  4  10.5   5.8 |  12.4  54.3  205   3  2   8.6   4.7
  7250  14.2  57.6  240   8  4   8.7   4.8 |  13.0  55.4  205   2  1   8.1   4.4
  7000  14.7  58.5  240   9  4   7.2   4.0 |  13.5  56.3  210   2  1   7.4   4.0
  6750  15.4  59.7  245   9  5   9.9   5.4 |  14.1  57.4  220   2  1   8.2   4.5
  6500  16.2  61.2  245   8  4  11.3   6.2 |  14.7  58.5  215   1  1   8.6   4.7
  6250  16.9  62.4  245   8  4   9.8   5.4 |  15.4  59.7  215   1  0   9.3   5.1
  6000  17.6  63.7  245   8  4   9.3   5.1 |  16.1  61.0  240   1  0  10.5   5.8
  5750  18.3  64.9  245   8  4   9.0   5.0 |  16.8  62.2  280   1  0   8.2   4.5
  5500  19.0  66.2  245   7  4  10.3   5.6 |  17.3  63.1  245   1  0   7.5   4.1
  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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