Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0638 MDT Friday, April 22, 2016

This forecast is for Friday, April 22, 2016:

If the trigger temperature of 72.5 F/22.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1193 ft/min (6.1 m/s)
   Maximum height of thermals.................. 19163 ft MSL (14324 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1245 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................. 9371 ft MSL (4531 ft AGL)
Thermal soaring outlook for Saturday 04/23..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:26:49 / 19:57:59 MDT
Total possible sunshine........... 13 hr 31 min 10 sec (811 min 10 sec)
Altitude of sun at 13:12:34 MDT... 63.42 degrees

Upper air data from rawinsonde observation taken on 04/22/2016 at 0600 MDT

Freezing level.................. 12963 ft MSL (8124 ft AGL)
Convective condensation level... 16754 ft MSL (11915 ft AGL)
Lifted condensation level....... 17379 ft MSL (12539 ft AGL)
Lifted index.................... +1.7
K index......................... +12.5

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  -64.2 -83.6   265   29   15  -3.5  -1.9   93.6 200.5    38.5      M    M
 45000  -68.8 -91.8   240   23   12  -9.5  -5.2   61.2 142.1    21.4      M    M
 40000  -63.2 -81.8   255   19   10   8.6   4.7   46.6 115.8    13.4      M    M
 38000  -58.1 -72.6   260   20   10   7.5   4.1   45.4 113.8    13.0      M    M
 36000  -53.8 -64.8   265   22   11   6.5   3.5   42.0 107.6    11.1      M    M
 34000  -49.5 -57.1   270   22   11   8.5   4.6   39.8 103.7     9.8      M    M
 32000  -44.4 -47.9   275   19   10   8.5   4.7   38.8 101.9     9.3      M    M
 30000  -39.3 -38.7   265   16    8   8.4   4.6   37.9 100.1     8.8      M    M
 29000  -36.8 -34.2   260   14    7   8.1   4.5   37.3  99.1     8.5      M    M
 28000  -34.4 -29.9   265   13    7   8.1   4.4   36.5  97.8     8.0      M    M
 27000  -32.0 -25.6   270   12    6   8.1   4.4   35.9  96.6     7.6      M    M
 26000  -29.5 -21.1   280   11    6   8.3   4.5   35.4  95.7     7.3      M    M
 25000  -27.1 -16.8   280   16    8   8.3   4.5   34.8  94.7     6.9      M    M
 24000  -24.6 -12.3   290   13    7   7.9   4.3   34.3  93.7     6.6      M    M
 23000  -22.3  -8.1   275   14    7   7.7   4.2   33.5  92.2     6.0      M    M
 22000  -20.0  -4.0   260   16    8   7.6   4.2   32.6  90.7     5.3      M    M
 21000  -17.7   0.1   250   19   10   7.7   4.2   31.8  89.3     4.7      M    M
 20000  -16.9   1.6   240   23   12  -7.6  -4.2   29.5  85.1     2.8      M    M
 19500  -16.9   1.6   240   22   11  -0.8  -0.4   27.7  81.9     1.3      M    M
 19000  -16.4   2.5   240   21   11   5.2   2.9   25.8  78.5    -0.5   1374  7.0
 18500  -15.4   4.3   240   22   11   8.5   4.6   25.4  77.7    -0.9   1328  6.7
 18000  -14.1   6.6   240   22   11   9.0   5.0   25.2  77.4    -1.1   1274  6.5
 17500  -12.7   9.1   235   23   12   9.0   4.9   25.1  77.2    -1.2   1218  6.2
 17000  -11.3  11.7   235   23   12   9.5   5.2   25.0  77.1    -1.2   1162  5.9
 16500   -9.9  14.2   235   24   12   9.5   5.2   25.0  77.1    -1.2   1105  5.6
 16000   -8.5  16.7   235   24   12   9.5   5.2   25.1  77.1    -1.3   1048  5.3
 15500   -7.1  19.2   235   25   13   9.5   5.2   25.0  77.1    -1.3    990  5.0
 15000   -5.7  21.7   235   25   13   9.5   5.2   25.0  77.1    -1.3    933  4.7
 14500   -4.3  24.3   230   23   12   9.5   5.2   25.0  77.0    -1.3    876  4.4
 14000   -2.9  26.8   230   21   11   9.5   5.2   25.0  77.0    -1.4    819  4.2
 13500   -1.4  29.5   230   20   11   9.5   5.2   24.9  76.8    -1.5    761  3.9
 13000   -0.0  32.0   230   20   10   9.5   5.2   24.8  76.7    -1.5    704  3.6
 12500    1.4  34.5   230   19   10   9.5   5.2   24.8  76.6    -1.6    647  3.3
 12000    2.8  37.0   230   19   10   9.5   5.2   24.8  76.6    -1.6    590  3.0
 11500    4.2  39.6   230   19   10   9.5   5.2   24.7  76.4    -1.7    532  2.7
 11000    5.6  42.1   230   19   10   9.4   5.2   24.6  76.3    -1.8    475  2.4
 10500    7.1  44.8   215   20   11   8.2   4.5   24.5  76.1    -1.9    418  2.1
 10250    7.6  45.7   205   22   11   6.3   3.5   24.3  75.7    -2.2    395  2.0
 10000    8.1  46.6   200   22   11   6.9   3.8   24.0  75.2    -2.4    373  1.9
  9750    8.6  47.5   200   22   11   6.9   3.8   23.8  74.8    -2.6    351  1.8
  9500    9.1  48.4   195   22   12   6.9   3.8   23.6  74.4    -2.9    328  1.7
  9250    9.6  49.3   195   23   12   6.9   3.8   23.4  74.1    -3.1    305  1.6
  9000   10.1  50.2   190   23   12   6.9   3.8   23.2  73.7    -3.3    283  1.4
  8750   10.6  51.1   185   22   11   6.9   3.8   22.9  73.3    -3.5    260  1.3
  8500   11.1  52.0   175   21   11   7.0   3.8   22.7  72.9    -3.8    237  1.2
  8250   11.6  52.9   170   20   10   6.8   3.7   22.5  72.5    -4.0    215  1.1
  8000   12.1  53.8   160   20   10   7.4   4.0   22.3  72.1    -4.2    192  1.0
  7750   12.6  54.7   155   19   10   3.3   1.8   22.0  71.6    -4.5    171  0.9
  7500   12.3  54.1   150   17    9 -12.3  -6.7   21.0  69.8    -5.5    172  0.9
  7250   11.2  52.2   145   16    8  -9.7  -5.3   19.1  66.3    -7.4    198  1.0
  7000   11.2  52.2   135   15    8   5.7   3.1   18.3  65.0    -8.2    191  1.0
  6750   11.7  53.1   135   16    8   7.1   3.9   18.1  64.5    -8.4    168  0.9
  6500   12.2  54.0   135   18    9   6.7   3.7   17.9  64.1    -8.7    146  0.7
  6250   12.7  54.9   135   19   10   6.8   3.8   17.6  63.7    -8.9    124  0.6
  6000   13.2  55.8   135   21   11   6.8   3.8   17.4  63.4    -9.2    101  0.5
  5750   13.7  56.7   135   19   10   6.7   3.7   17.2  63.0    -9.4     79  0.4
  5500   14.2  57.6   130   16    8   7.2   3.9   17.0  62.5    -9.7     56  0.3
  5250   14.7  58.5   125   13    7   5.5   3.0   16.8  62.2    -9.9     34  0.2
  5000   14.5  58.1   115   11    5 -16.4  -9.0   15.8  60.5   -10.9     33  0.2

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

           04/22/2016 at 0900 MDT          |       04/22/2016 at 1200 MDT
                                           |
K index... +16.3  LI... +273.8             | K index... +11.7  LI... +271.7
CAPE... 0.0  CIN... 0.0                    | CAPE... +43.8  CIN... -77.0
                                           |
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 -65.0 -85.0  255  24 12  -1.9  -1.0 | -64.6 -84.3  260  26 14  -1.6  -0.9
 45000 -67.5 -89.5  250  34 17   3.2   1.8 | -66.7 -88.1  245  35 18   2.6   1.4
 40000 -62.7 -80.9  240  23 12   3.3   1.8 | -62.2 -80.0  225  32 16   2.7   1.5
 38000 -58.6 -73.5  240  22 11   7.0   3.8 | -58.6 -73.5  220  32 16   6.8   3.7
 36000 -54.5 -66.1  240  22 11   7.0   3.8 | -54.5 -66.1  220  31 16   6.8   3.7
 34000 -49.8 -57.6  240  21 11   8.7   4.8 | -50.0 -58.0  220  31 16   8.7   4.7
 32000 -44.6 -48.3  245  19 10   8.7   4.8 | -44.8 -48.6  215  30 16   8.7   4.7
 30000 -39.5 -39.1  245  18  9   8.2   4.5 | -39.8 -39.6  215  30 15   7.9   4.3
 29000 -37.0 -34.6  245  17  9   8.2   4.5 | -37.5 -35.5  215  29 15   7.9   4.3
 28000 -34.5 -30.1  240  16  8   8.2   4.5 | -35.1 -31.2  215  29 15   7.9   4.3
 27000 -32.1 -25.8  240  15  8   8.2   4.5 | -32.1 -25.8  215  28 15   8.0   4.4
 26000 -29.0 -20.2  235  14  7   8.2   4.5 | -29.7 -21.5  220  28 14   8.0   4.4
 25000 -26.6 -15.9  235  13  7   8.2   4.5 | -27.3 -17.1  220  27 14   8.0   4.4
 24000 -24.4 -11.9  235  14  7   6.3   3.5 | -25.1 -13.2  225  27 14   6.9   3.8
 23000 -22.5  -8.5  240  17  9   6.4   3.5 | -23.0  -9.4  230  28 14   6.9   3.8
 22000 -20.6  -5.1  240  20 10   6.3   3.5 | -20.9  -5.6  230  29 15   6.9   3.8
 21000 -18.8  -1.8  240  22 12   5.4   2.9 | -19.1  -2.4  230  30 15   5.9   3.2
 20000 -17.3   0.9  240  25 13   5.4   2.9 | -17.4   0.7  230  31 16   5.9   3.2
 19500 -16.5   2.3  240  27 14   5.4   3.0 | -16.5   2.3  225  32 16   6.0   3.3
 19000 -15.7   3.7  240  28 15   5.8   3.2 | -15.7   3.7  225  33 17   6.5   3.6
 18500 -14.7   5.5  235  28 14   7.0   3.9 | -14.5   5.9  225  32 17   8.0   4.4
 18000 -13.7   7.3  235  27 14   6.9   3.8 | -13.4   7.9  225  32 16   7.9   4.3
 17500 -12.6   9.3  230  26 13   9.2   5.0 | -12.1  10.2  225  31 16   9.4   5.1
 17000 -11.2  11.8  230  23 12   9.4   5.2 | -10.7  12.7  225  30 16   9.4   5.2
 16500  -9.9  14.2  230  21 11   9.3   5.1 |  -9.3  15.3  225  29 15   9.4   5.2
 16000  -8.5  16.7  230  20 10   9.2   5.0 |  -7.9  17.8  225  28 15   9.4   5.1
 15500  -7.1  19.2  230  18  9   9.2   5.0 |  -6.5  20.3  225  28 14   9.4   5.1
 15000  -5.8  21.6  230  18  9   8.9   4.9 |  -5.1  22.8  225  27 14   9.0   5.0
 14500  -4.5  23.9  230  18  9   8.9   4.9 |  -3.8  25.2  225  26 13   9.0   4.9
 14000  -3.1  26.4  230  18  9   9.5   5.2 |  -2.4  27.7  225  26 13   9.5   5.2
 13500  -1.7  28.9  235  18  9   9.5   5.2 |  -1.0  30.2  220  25 13   9.5   5.2
 13000   0.4  32.7  230  18  9   9.2   5.0 |   1.1  34.0  220  25 13   9.1   5.0
 12500   1.8  35.2  230  18  9   9.2   5.0 |   2.5  36.5  220  25 13   9.1   5.0
 12000   3.1  37.6  225  18  9   9.2   5.1 |   3.8  38.8  215  24 13   9.2   5.0
 11500   4.5  40.1  225  19 10   9.2   5.1 |   5.2  41.4  215  24 12   9.1   5.0
 11000   5.8  42.4  220  19 10   8.2   4.5 |   6.5  43.7  215  24 12   8.5   4.7
 10500   7.1  44.8  220  20 10   4.9   2.7 |   7.8  46.0  210  23 12   5.7   3.1
 10250   7.3  45.1  220  20 10   5.7   3.1 |   8.1  46.6  210  23 12   6.0   3.3
 10000   8.0  46.4  215  20 10  10.7   5.9 |   8.8  47.8  205  23 12  10.1   5.6
  9750   8.7  47.7  215  20 10   9.5   5.2 |   9.4  48.9  205  22 11   9.2   5.0
  9500   9.5  49.1  215  20 10   9.3   5.1 |  10.1  50.2  200  22 11   9.1   5.0
  9250  10.1  50.2  210  20 10   6.4   3.5 |  10.7  51.3  200  22 11   7.1   3.9
  9000  10.5  50.9  210  19 10   6.1   3.3 |  11.1  52.0  195  21 11   6.5   3.6
  8750  11.0  51.8  205  19 10   7.6   4.1 |  11.6  52.9  190  20 10   7.2   3.9
  8500  11.5  52.7  200  19 10   6.5   3.6 |  12.1  53.8  185  19 10   6.8   3.8
  8250  11.9  53.4  195  19 10   5.5   3.0 |  12.5  54.5  180  17  9   6.5   3.6
  8000  12.3  54.1  190  18 10   3.7   2.0 |  13.0  55.4  175  16  8   6.1   3.3
  7750  12.5  54.5  185  18  9   2.5   1.4 |  13.4  56.1  175  15  7   5.0   2.7
  7500  12.7  54.9  175  18  9   2.1   1.1 |  13.7  56.7  170  13  7   7.6   4.2
  7250  12.8  55.0  170  17  9   1.2   0.7 |  14.5  58.1  170  13  7  10.5   5.8
  7000  12.9  55.2  165  17  9   1.3   0.7 |  15.2  59.4  170  13  7  10.0   5.5
  6750  12.9  55.2  165  16  8   1.0   0.6 |  16.0  60.8  170  13  7  10.0   5.5
  6500  12.9  55.2  160  15  8  -0.8  -0.4 |  16.7  62.1  170  12  6  10.5   5.8
  6250  12.8  55.0  155  13  7  -1.1  -0.6 |  17.5  63.5  170  12  6  11.1   6.1
  6000  12.6  54.7  145  10  5  -2.9  -1.6 |  18.3  64.9  170  12  6  10.3   5.6
  5750  12.4  54.3  125   7  4   1.0   0.5 |  19.1  66.4  170  11  6  10.8   5.9
  5500  12.8  55.0  120   6  3   8.0   4.4 |  19.9  67.8  170  11  5  12.7   7.0
  5250  13.2  55.8  115   6  3   4.8   2.6 |  20.9  69.6  170  10  5  12.4   6.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/22/2016 at 1500 MDT          |       04/22/2016 at 1800 MDT
                                           |
K index... +23.2  LI... +271.3             | K index... +20.8  LI... +272.5
CAPE... +119.2  CIN... -10.3               | CAPE... +42.5  CIN... -23.7
                                           |
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 -63.4 -82.1  255  22 12  -0.6  -0.3 | -62.6 -80.7  260  19 10  -0.1  -0.1
 45000 -64.3 -83.7  240  28 14   0.7   0.4 | -62.8 -81.0  240  22 12   0.1   0.1
 40000 -62.9 -81.2  220  40 21   0.7   0.4 | -62.6 -80.7  230  44 23   0.3   0.2
 38000 -59.2 -74.6  220  41 21   7.8   4.3 | -59.3 -74.7  225  47 24   7.2   3.9
 36000 -54.5 -66.1  220  40 20   7.8   4.3 | -55.0 -67.0  225  48 25   7.2   3.9
 34000 -49.7 -57.5  220  39 20   8.2   4.5 | -50.5 -58.9  225  49 25   8.1   4.5
 32000 -44.8 -48.6  215  39 20   8.2   4.5 | -45.6 -50.1  220  48 25   8.1   4.5
 30000 -40.1 -40.2  215  39 20   7.7   4.2 | -40.7 -41.3  220  47 24   8.2   4.5
 29000 -37.8 -36.0  220  38 20   7.7   4.2 | -38.3 -36.9  220  47 24   8.2   4.5
 28000 -34.9 -30.8  220  37 19   7.7   4.2 | -35.3 -31.5  220  47 24   8.2   4.5
 27000 -32.5 -26.5  225  37 19   8.2   4.5 | -32.9 -27.2  225  46 24   7.5   4.1
 26000 -30.1 -22.2  230  37 19   8.2   4.5 | -30.7 -23.3  225  46 23   7.5   4.1
 25000 -27.6 -17.7  235  38 19   8.2   4.5 | -28.5 -19.3  230  45 23   7.5   4.1
 24000 -25.3 -13.5  240  37 19   6.8   3.8 | -26.2 -15.2  235  44 22   7.6   4.2
 23000 -23.3  -9.9  235  36 19   6.9   3.8 | -24.0 -11.2  240  40 20   7.6   4.2
 22000 -21.2  -6.2  235  35 18   6.9   3.8 | -21.7  -7.1  240  36 18   7.6   4.2
 21000 -19.2  -2.6  230  33 17   6.7   3.7 | -19.5  -3.1  240  33 17   7.6   4.2
 20000 -17.2   1.0  225  32 16   6.8   3.7 | -17.2   1.0  235  31 16   7.6   4.2
 19500 -16.3   2.7  220  32 16   6.8   3.7 | -16.1   3.0  235  30 15   7.6   4.2
 19000 -15.3   4.5  215  31 16   7.0   3.8 | -15.0   5.0  230  29 15   7.6   4.2
 18500 -14.2   6.4  215  31 16   7.8   4.3 | -13.9   7.0  225  28 15   7.8   4.3
 18000 -13.0   8.6  215  31 16   7.7   4.2 | -12.8   9.0  225  28 14   7.7   4.2
 17500 -11.8  10.8  215  31 16   8.5   4.7 | -11.6  11.1  220  28 14   8.3   4.6
 17000 -10.6  12.9  215  31 16   8.6   4.7 | -10.3  13.5  220  28 14   8.5   4.7
 16500  -9.3  15.3  215  31 16   8.8   4.9 |  -9.1  15.6  220  29 15   8.8   4.9
 16000  -8.0  17.6  215  30 16   9.2   5.0 |  -7.7  18.1  220  29 15   9.6   5.3
 15500  -6.6  20.1  215  30 16   9.2   5.0 |  -6.2  20.8  215  29 15   9.6   5.3
 15000  -5.2  22.6  210  30 15   9.4   5.2 |  -4.8  23.4  215  30 15   9.6   5.2
 14500  -3.8  25.2  210  29 15   9.4   5.1 |  -3.4  25.9  215  30 15   9.6   5.3
 14000  -2.4  27.7  210  28 14   9.7   5.3 |  -2.0  28.4  210  30 15   9.4   5.2
 13500  -0.3  31.5  210  27 14   9.6   5.3 |   0.1  32.2  210  29 15   9.4   5.2
 13000   1.1  34.0  210  26 13   9.4   5.2 |   1.5  34.7  210  29 15   9.2   5.1
 12500   2.5  36.5  210  25 13   9.4   5.2 |   2.9  37.2  210  28 15   9.2   5.1
 12000   3.9  39.0  210  24 12   9.1   5.0 |   4.3  39.7  210  27 14   9.3   5.1
 11500   5.3  41.5  210  22 11   9.2   5.0 |   5.7  42.3  210  26 14   9.5   5.2
 11000   6.5  43.7  210  20 11   8.3   4.6 |   6.9  44.4  205  25 13   8.1   4.5
 10500   7.7  45.9  215  19 10  11.2   6.1 |   8.2  46.8  205  24 12  10.7   5.9
 10250   8.7  47.7  215  19 10  11.9   6.5 |   9.1  48.4  205  23 12  11.8   6.5
 10000   9.4  48.9  215  19 10   8.6   4.7 |   9.8  49.6  205  23 12   8.8   4.8
  9750  10.1  50.2  215  18  9   9.6   5.2 |  10.5  50.9  205  22 11   9.2   5.1
  9500  10.8  51.4  215  18  9   9.1   5.0 |  11.2  52.2  205  21 11   9.1   5.0
  9250  11.5  52.7  215  17  9   9.2   5.0 |  11.8  53.2  210  20 10   8.9   4.9
  9000  12.2  54.0  220  17  9   9.9   5.4 |  12.5  54.5  210  20 10   9.2   5.1
  8750  12.9  55.2  220  17  9  10.2   5.6 |  13.2  55.8  210  19 10   9.6   5.3
  8500  13.7  56.7  220  17  9  10.2   5.6 |  13.9  57.0  210  18  9   9.5   5.2
  8250  14.5  58.1  220  16  8  10.8   5.9 |  14.6  58.3  210  18  9   9.8   5.4
  8000  15.3  59.5  220  16  8  10.0   5.5 |  15.4  59.7  210  17  9   9.5   5.2
  7750  15.9  60.6  220  16  8   8.9   4.9 |  16.0  60.8  210  17  9   8.9   4.9
  7500  16.6  61.9  220  16  8   9.7   5.3 |  16.7  62.1  210  16  8   9.4   5.2
  7250  17.4  63.3  220  16  8  10.8   5.9 |  17.5  63.5  210  16  8  10.4   5.7
  7000  18.2  64.8  220  15  8  10.1   5.5 |  18.2  64.8  210  15  8  10.3   5.6
  6750  18.9  66.0  220  15  8   8.7   4.8 |  19.0  66.2  210  15  8   9.6   5.3
  6500  19.6  67.3  225  15  8  10.3   5.6 |  19.7  67.5  210  14  7   9.8   5.4
  6250  20.4  68.7  225  14  7  12.0   6.6 |  20.4  68.7  210  14  7   9.9   5.5
  6000  21.3  70.3  225  14  7  10.6   5.8 |  21.2  70.2  210  13  7   9.9   5.4
  5750  22.0  71.6  225  13  7  10.7   5.9 |  21.9  71.4  210  12  6   9.5   5.2
  5500  22.9  73.2  225  13  6  13.1   7.2 |  22.5  72.5  210  11  6   8.4   4.6
  5250  23.9  75.0  225  13  6  14.5   7.9 |  23.1  73.6  215  11  6   7.6   4.2
  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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