Soaring Guidance
Issued by NWS Grand Junction, CO

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151
UXUS97 KGJT 291242
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0642 MDT Thursday, September 29, 2016

This forecast is for Thursday, September 29, 2016:

If the trigger temperature of 75.9 F/24.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 162 ft/min (0.8 m/s)
   Maximum height of thermals.................. 9683 ft MSL (4844 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1430 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................. 5254 ft MSL (414 ft AGL)
Thermal soaring outlook for Friday 09/30....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:08:49 / 19:00:34 MDT
Total possible sunshine........... 11 hr 51 min 46 sec (711 min 46 sec)
Altitude of sun at 13:04:12 MDT... 48.09 degrees

Upper air data from rawinsonde observation taken on 09/29/2016 at 0600 MDT

Freezing level.................. 13593 ft MSL (8754 ft AGL)
Convective condensation level... 14571 ft MSL (9732 ft AGL)
Lifted condensation level....... 13619 ft MSL (8780 ft AGL)
Lifted index.................... +2.5
K index......................... +26.9

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  -64.7 -84.5   240   25   13   4.8   2.6   88.4 191.1    36.9      M    M
 45000  -58.6 -73.5   215   41   21  -0.7  -0.4   72.8 163.1    30.0      M    M
 40000  -53.2 -63.8   245   61   31   2.7   1.5   58.5 137.4    22.6      M    M
 38000  -50.3 -58.5   245   54   28   6.2   3.4   53.9 129.1    20.1      M    M
 36000  -47.4 -53.3   240   47   24   0.8   0.4   49.9 121.8    17.8      M    M
 34000  -44.5 -48.1   225   39   20   7.3   4.0   45.7 114.2    15.2      M    M
 32000  -39.2 -38.6   215   37   19   9.5   5.2   44.9 112.9    15.1      M    M
 30000  -33.3 -27.9   215   37   19   8.6   4.7   44.2 111.5    14.9      M    M
 29000  -30.7 -23.3   210   37   19   7.6   4.2   43.7 110.6    14.7      M    M
 28000  -28.7 -19.7   210   36   19   6.7   3.7   42.5 108.4    13.9      M    M
 27000  -26.7 -16.1   205   36   19   7.5   4.1   41.4 106.5    13.2      M    M
 26000  -24.4 -11.9   205   36   19   8.3   4.5   40.6 105.0    12.7      M    M
 25000  -21.6  -6.9   200   36   18   5.0   2.7   40.6 105.1    12.8      M    M
 24000  -19.5  -3.1   200   34   17   7.0   3.9   39.3 102.8    11.9      M    M
 23000  -17.5   0.5   195   32   17   7.1   3.9   38.2 100.8    11.1      M    M
 22000  -15.4   4.3   190   31   16   7.1   3.9   37.3  99.1    10.3      M    M
 21000  -13.3   8.1   190   29   15   7.1   3.9   36.4  97.5     9.7      M    M
 20000  -11.3  11.7   185   28   14   7.2   3.9   35.7  96.2     9.1      M    M
 19500  -10.2  13.6   185   29   15   7.2   3.9   35.2  95.4     8.7      M    M
 19000   -9.2  15.4   185   31   16   6.1   3.3   34.7  94.5     8.3      M    M
 18500   -8.5  16.7   185   31   16   4.8   2.6   33.9  93.0     7.6      M    M
 18000   -7.8  18.0   180   30   16   4.8   2.7   33.0  91.4     6.8      M    M
 17500   -7.1  19.2   180   29   15   4.8   2.6   32.2  89.9     6.1      M    M
 17000   -6.5  20.3   175   29   15   4.2   2.3   31.3  88.3     5.4      M    M
 16500   -5.5  22.1   170   28   14   7.5   4.1   29.9  85.8     4.2      M    M
 16000   -3.9  25.0   170   27   14   8.2   4.5   30.2  86.3     4.4      M    M
 15500   -3.4  25.9   175   25   13   2.2   1.2   29.1  84.5     3.4      M    M
 15000   -2.9  26.8   175   24   12   6.4   3.5   28.1  82.6     2.5      M    M
 14500   -1.8  28.8   180   23   12   7.3   4.0   27.7  81.9     2.1      M    M
 14000   -0.7  30.7   180   22   11   7.4   4.1   27.4  81.2     1.8      M    M
 13500    0.4  32.7   185   21   11   7.4   4.1   26.9  80.5     1.4      M    M
 13000    1.5  34.7   190   20   10   7.4   4.1   26.5  79.8     1.0      M    M
 12500    2.6  36.7   195   19   10   7.3   4.0   26.2  79.1     0.7      M    M
 12000    3.7  38.7   200   18    9   8.6   4.7   25.9  78.6     0.4      M    M
 11500    5.1  41.2   200   14    7   8.9   4.9   25.7  78.3     0.3      M    M
 11000    6.4  43.5   200   10    5   9.0   4.9   25.6  78.1     0.2      M    M
 10500    7.7  45.9   195    6    3   9.2   5.1   25.5  77.9     0.1      M    M
 10250    8.4  47.1   190    7    3   9.4   5.2   25.5  77.9     0.1      M    M
 10000    9.1  48.4   185    7    4   9.4   5.1   25.4  77.8     0.0      M    M
  9750    9.8  49.6   180    8    4   9.4   5.2   25.4  77.8     0.0      M    M
  9500   10.5  50.9   175    9    4   9.4   5.2   25.4  77.7    -0.0    342  1.7
  9250   11.2  52.2   175    9    5   9.4   5.2   25.4  77.7    -0.0    314  1.6
  9000   11.9  53.4   170   10    5   9.4   5.2   25.4  77.7    -0.0    285  1.5
  8750   12.6  54.7   170    9    4   9.3   5.1   25.3  77.6    -0.1    257  1.3
  8500   13.3  55.9   165    7    4   9.8   5.4   25.3  77.5    -0.1    229  1.2
  8250   14.0  57.2   165    6    3   8.0   4.4   25.3  77.5    -0.2    201  1.0
  8000   14.5  58.1   160    4    2   5.5   3.0   25.0  77.0    -0.4    179  0.9
  7750   14.9  58.8   170    3    1   5.3   2.9   24.7  76.4    -0.8    160  0.8
  7500   15.3  59.5   215    1    1   5.5   3.0   24.3  75.8    -1.1    142  0.7
  7250   15.6  60.1   280    2    1   5.1   2.8   24.0  75.2    -1.5    123  0.6
  7000   16.0  60.8   300    4    2   6.3   3.5   23.7  74.6    -1.8    104  0.5
  6750   16.6  61.9   295    3    2   9.3   5.1   23.5  74.4    -2.0     79  0.4
  6500   17.4  63.3   280    3    1  10.2   5.6   23.6  74.4    -1.9     49  0.2
  6250   18.1  64.6   260    2    1  10.4   5.7   23.6  74.4    -1.9     19  0.1
  6000   18.9  66.0   230    2    1   8.9   4.9   23.6  74.5    -1.9      M    M
  5750   19.4  66.9   225    2    1   5.8   3.2   23.4  74.2    -2.1      M    M
  5500   19.8  67.6   230    2    1   4.9   2.7   23.1  73.5    -2.4      M    M
  5250   20.1  68.2   230    2    1   5.3   2.9   22.7  72.9    -2.8      M    M
  5000   20.2  68.4   255    1    0  -6.5  -3.5   22.1  71.8    -3.4      M    M

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

           09/29/2016 at 0900 MDT          |       09/29/2016 at 1200 MDT
                                           |
K index... +29.0  LI... +273.0             | K index... +28.0  LI... +273.2
CAPE... +43.1  CIN... -74.9                | CAPE... +14.1  CIN... -87.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.7 -82.7  240  24 12   2.1   1.1 | -63.9 -83.0  240  26 13   2.5   1.4
 45000 -58.9 -74.0  235  39 20   5.3   2.9 | -58.9 -74.0  240  41 21   4.8   2.6
 40000 -51.1 -60.0  240  49 25   4.0   2.2 | -51.7 -61.1  235  54 28   5.3   2.9
 38000 -48.7 -55.7  240  49 25   4.0   2.2 | -48.5 -55.3  235  53 27   5.3   2.9
 36000 -46.3 -51.3  245  49 25   4.1   2.2 | -45.3 -49.5  230  51 26   5.3   2.9
 34000 -43.0 -45.4  240  42 21   5.9   3.2 | -42.0 -43.6  230  42 22   5.7   3.1
 32000 -39.0 -38.2  230  32 16   5.5   3.0 | -38.2 -36.8  225  29 15   5.4   3.0
 30000 -33.9 -29.0  220  31 16   9.3   5.1 | -33.8 -28.8  215  24 12   7.7   4.2
 29000 -31.1 -24.0  215  32 17   9.3   5.1 | -31.5 -24.7  210  22 11   7.7   4.2
 28000 -28.4 -19.1  210  33 17   8.4   4.6 | -29.2 -20.6  200  20 10   8.3   4.6
 27000 -26.0 -14.8  205  33 17   7.9   4.3 | -26.7 -16.1  205  21 11   8.7   4.8
 26000 -23.7 -10.7  205  32 16   7.9   4.3 | -24.1 -11.4  205  23 12   8.7   4.8
 25000 -21.4  -6.5  200  32 16   7.9   4.3 | -21.6  -6.9  205  24 12   8.7   4.8
 24000 -19.3  -2.7  200  32 16   7.0   3.8 | -19.4  -2.9  210  24 13   7.2   3.9
 23000 -17.2   1.0  200  32 16   7.0   3.9 | -17.2   1.0  210  25 13   7.2   4.0
 22000 -15.2   4.6  195  32 17   6.9   3.8 | -15.1   4.8  210  26 13   7.1   3.9
 21000 -13.3   8.1  195  33 17   6.3   3.5 | -13.2   8.2  210  28 14   6.4   3.5
 20000 -11.4  11.5  195  33 17   6.4   3.5 | -11.4  11.5  215  30 15   6.4   3.5
 19500 -10.5  13.1  200  34 17   6.4   3.5 | -10.5  13.1  215  31 16   6.4   3.5
 19000  -9.6  14.7  200  34 18   6.2   3.4 |  -9.6  14.7  215  32 17   6.2   3.4
 18500  -8.3  17.1  200  35 18   6.3   3.4 |  -8.2  17.2  210  35 18   6.2   3.4
 18000  -7.4  18.7  195  35 18   5.0   2.8 |  -7.4  18.7  210  37 19   5.6   3.1
 17500  -6.7  19.9  195  35 18   5.0   2.7 |  -6.5  20.3  205  38 20   5.6   3.1
 17000  -6.0  21.2  195  36 18   4.9   2.7 |  -5.7  21.7  200  39 20   5.6   3.1
 16500  -5.3  22.5  190  36 18   4.8   2.7 |  -4.9  23.2  200  39 20   5.5   3.0
 16000  -4.6  23.7  190  36 18   4.8   2.6 |  -4.1  24.6  195  39 20   5.5   3.0
 15500  -3.9  25.0  185  35 18   5.8   3.2 |  -3.3  26.1  195  39 20   5.7   3.1
 15000  -3.0  26.6  185  34 18   5.7   3.1 |  -2.5  27.5  190  39 20   5.6   3.1
 14500  -2.2  28.0  185  33 17   6.0   3.3 |  -1.6  29.1  190  38 20   6.5   3.5
 14000  -1.3  29.7  185  30 16   6.1   3.3 |  -0.7  30.7  190  37 19   6.5   3.6
 13500  -0.4  31.3  180  28 14   6.7   3.7 |   0.3  32.5  190  36 18   6.5   3.5
 13000   0.6  33.1  180  25 13   6.9   3.8 |   1.2  34.2  190  33 17   6.5   3.5
 12500   1.6  34.9  180  22 11   7.3   4.0 |   2.2  36.0  185  31 16   7.1   3.9
 12000   2.6  36.7  180  19 10   7.6   4.2 |   3.3  37.9  185  27 14   7.5   4.1
 11500   3.7  38.7  180  17  9   7.5   4.1 |   4.4  39.9  185  24 12   6.6   3.6
 11000   4.8  40.6  185  15  8   7.2   4.0 |   5.1  41.2  185  19 10   5.6   3.1
 10500   5.8  42.4  190  13  7   6.0   3.3 |   5.8  42.4  185  15  8   5.5   3.0
 10250   6.2  43.2  195  12  6   5.1   2.8 |   6.2  43.2  190  13  7   5.8   3.2
 10000   6.6  43.9  195  11  6   7.2   4.0 |   6.7  44.1  190  12  6   7.9   4.3
  9750   7.2  45.0  200  10  5   8.1   4.4 |   7.3  45.1  195  11  5   9.1   5.0
  9500   7.7  45.9  205  10  5   6.2   3.4 |   7.9  46.2  200  10  5   6.7   3.7
  9250   8.1  46.6  215   9  5   4.6   2.5 |   8.3  46.9  205   9  4   4.7   2.6
  9000   8.5  47.3  220   9  5   6.5   3.5 |   8.7  47.7  215   8  4   6.3   3.4
  8750   9.0  48.2  225   9  5   7.7   4.2 |   9.2  48.6  220   7  4   6.8   3.7
  8500   9.5  49.1  230   9  5   5.9   3.2 |   9.6  49.3  230   6  3   4.7   2.6
  8250   9.9  49.8  240   9  5   5.0   2.7 |   9.8  49.6  240   6  3   3.5   1.9
  8000  10.2  50.4  245   9  5   5.8   3.2 |  10.1  50.2  250   5  3   4.3   2.3
  7750  10.7  51.3  250   9  5   5.5   3.0 |  10.4  50.7  265   4  2   3.8   2.1
  7500  11.0  51.8  260   9  5   4.3   2.3 |  10.6  51.1  285   4  2   2.4   1.3
  7250  11.3  52.3  265   9  5   4.3   2.4 |  10.7  51.3  305   4  2   2.6   1.4
  7000  11.6  52.9  275  10  5   3.8   2.1 |  10.9  51.6  325   4  2   1.5   0.8
  6750  11.8  53.2  280  10  5   2.0   1.1 |  10.9  51.6  340   5  3   3.2   1.7
  6500  11.9  53.4  285   9  5   1.1   0.6 |  11.3  52.3  345   5  3   5.7   3.1
  6250  12.1  53.8  290   8  4   1.8   1.0 |  11.6  52.9  350   6  3   4.6   2.5
  6000  12.2  54.0  300   8  4   0.1   0.0 |  12.0  53.6  355   6  3   6.4   3.5
  5750  12.3  54.1  300   7  4   2.8   1.6 |  12.7  54.9  355   6  3  12.9   7.1
  5500  12.9  55.2  300   6  3  12.1   6.6 |  13.9  57.0  355   6  3  18.8  10.3
  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

           09/29/2016 at 1500 MDT          |       09/29/2016 at 1800 MDT
                                           |
K index... +27.5  LI... +272.6             | K index... +26.6  LI... +271.6
CAPE... +27.6  CIN... -25.2                | CAPE... +112.9  CIN... -71.1
                                           |
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 -63.6 -82.5  245  23 12   3.0   1.6 | -63.5 -82.3  245  24 12   3.2   1.8
 45000 -58.4 -73.1  240  40 20   4.2   2.3 | -58.0 -72.4  245  36 19   4.1   2.3
 40000 -52.1 -61.8  235  60 31   4.6   2.5 | -51.8 -61.2  245  55 28   3.6   2.0
 38000 -49.4 -56.9  235  59 30   4.5   2.5 | -49.6 -57.3  235  58 30   3.7   2.0
 36000 -46.6 -51.9  235  58 30   4.5   2.5 | -47.4 -53.3  225  62 32   3.7   2.1
 34000 -42.6 -44.7  235  49 25   7.4   4.1 | -43.2 -45.8  225  55 28   8.0   4.4
 32000 -37.6 -35.7  230  37 19   7.3   4.0 | -37.8 -36.0  235  43 22   7.9   4.3
 30000 -33.0 -27.4  220  29 15   7.7   4.2 | -32.7 -26.9  235  35 18   8.7   4.8
 29000 -30.7 -23.3  210  26 13   7.7   4.2 | -30.1 -22.2  230  31 16   8.8   4.8
 28000 -28.4 -19.1  200  24 12   7.9   4.3 | -27.5 -17.5  230  27 14   7.8   4.3
 27000 -26.1 -15.0  205  24 12   8.0   4.4 | -25.4 -13.7  225  26 13   7.1   3.9
 26000 -23.7 -10.7  210  25 13   8.0   4.4 | -23.3  -9.9  220  24 13   7.1   3.9
 25000 -21.4  -6.5  215  25 13   8.0   4.4 | -21.2  -6.2  220  23 12   7.2   3.9
 24000 -19.2  -2.6  215  26 13   7.2   4.0 | -19.2  -2.6  220  22 11   6.7   3.7
 23000 -17.1   1.2  215  26 14   7.2   4.0 | -17.2   1.0  220  22 11   6.7   3.7
 22000 -15.0   5.0  220  27 14   7.2   3.9 | -15.3   4.5  220  21 11   6.7   3.7
 21000 -13.0   8.6  215  27 14   6.7   3.7 | -13.4   7.9  220  20 10   6.3   3.4
 20000 -11.0  12.2  215  27 14   6.7   3.7 | -11.6  11.1  220  19 10   6.3   3.5
 19500 -10.1  13.8  215  28 14   6.7   3.7 | -10.7  12.7  220  19 10   6.3   3.5
 19000  -8.6  16.5  215  27 14   6.6   3.6 |  -9.3  15.3  220  18  9   5.8   3.2
 18500  -7.7  18.1  220  27 14   6.6   3.6 |  -8.5  16.7  220  18  9   5.8   3.2
 18000  -6.7  19.9  220  27 14   6.0   3.3 |  -7.7  18.1  220  17  9   5.9   3.2
 17500  -5.9  21.4  220  26 13   5.9   3.3 |  -6.8  19.8  225  17  9   5.9   3.2
 17000  -5.0  23.0  220  26 13   5.9   3.2 |  -5.9  21.4  230  16  8   6.1   3.3
 16500  -4.2  24.4  225  25 13   5.7   3.1 |  -5.0  23.0  230  16  8   6.6   3.6
 16000  -3.3  26.1  225  25 13   5.7   3.1 |  -4.0  24.8  235  16  8   6.5   3.5
 15500  -2.5  27.5  225  26 13   5.7   3.1 |  -3.0  26.6  235  17  9   7.6   4.2
 15000  -1.7  28.9  230  26 13   5.6   3.1 |  -1.9  28.6  240  17  9   7.4   4.1
 14500  -0.8  30.6  230  27 14   6.3   3.4 |  -0.8  30.6  240  18  9   7.8   4.3
 14000   0.1  32.2  225  27 14   6.3   3.5 |   0.4  32.7  240  19 10   7.9   4.3
 13500   1.0  33.8  225  28 14   6.9   3.8 |   1.6  34.9  235  19 10   7.9   4.3
 13000   2.1  35.8  220  27 14   7.2   4.0 |   2.7  36.9  235  20 10   7.9   4.4
 12500   3.1  37.6  215  26 13   7.2   4.0 |   3.9  39.0  235  20 10   7.9   4.3
 12000   4.1  39.4  210  22 11   7.2   3.9 |   5.0  41.0  235  19 10   7.8   4.3
 11500   5.1  41.2  205  19 10   6.9   3.8 |   6.1  43.0  235  18  9   7.7   4.2
 11000   6.0  42.8  200  17  9   6.6   3.6 |   7.1  44.8  235  16  8   7.4   4.0
 10500   7.0  44.6  195  14  7   5.6   3.1 |   8.2  46.8  235  14  7   6.4   3.5
 10250   7.3  45.1  190  14  7   5.3   2.9 |   8.6  47.5  235  13  7   6.0   3.3
 10000   7.8  46.0  190  13  7   7.6   4.2 |   9.1  48.4  235  12  6   7.9   4.3
  9750   8.4  47.1  190  12  6   8.6   4.7 |   9.6  49.3  235  11  6   8.5   4.7
  9500   9.0  48.2  185  11  6   7.0   3.8 |  10.2  50.4  235  10  5   7.6   4.2
  9250   9.4  48.9  185  10  5   5.2   2.9 |  10.7  51.3  240   9  4   6.6   3.6
  9000   9.8  49.6  190   9  5   6.9   3.8 |  11.2  52.2  240   8  4   7.0   3.9
  8750  10.4  50.7  190   7  4   7.9   4.3 |  11.7  53.1  240   7  4   7.3   4.0
  8500  10.9  51.6  195   6  3   5.4   3.0 |  12.2  54.0  245   6  3   6.5   3.6
  8250  11.2  52.2  205   4  2   4.1   2.2 |  12.6  54.7  245   5  3   5.8   3.2
  8000  11.5  52.7  240   2  1   4.5   2.5 |  13.0  55.4  250   4  2   6.2   3.4
  7750  11.8  53.2  290   3  1   4.6   2.5 |  13.5  56.3  255   3  2   6.0   3.3
  7500  12.1  53.8  310   4  2   4.7   2.6 |  13.9  57.0  265   3  1   5.0   2.7
  7250  12.4  54.3  315   5  2   4.8   2.6 |  14.2  57.6  285   2  1   4.5   2.5
  7000  12.7  54.9  320   5  3   4.3   2.4 |  14.6  58.3  310   2  1   4.6   2.5
  6750  13.1  55.6  320   6  3   7.6   4.2 |  15.0  59.0  330   2  1   5.5   3.0
  6500  13.8  56.8  320   6  3  10.6   5.8 |  15.4  59.7  330   3  1   6.3   3.5
  6250  14.5  58.1  315   6  3   9.8   5.4 |  15.8  60.4  325   3  1   5.9   3.2
  6000  15.3  59.5  315   6  3  10.1   5.5 |  16.2  61.2  325   3  2   6.9   3.8
  5750  16.2  61.2  315   6  3  15.3   8.4 |  16.8  62.2  320   3  2  10.8   5.9
  5500  17.6  63.7  315   6  3  23.5  12.9 |  17.8  64.0  320   3  2  14.3   7.9
  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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