Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 281249
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0649 MDT Sunday, September 28, 2014

This forecast is for Sunday, September 28, 2014:

If the trigger temperature of 66.9 F/19.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 276 ft/min (1.4 m/s)
   Maximum height of thermals.................. 9078 ft MSL (4239 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7084 ft MSL (2245 ft AGL)
Thermal soaring outlook for Monday 09/29....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:07:23 / 19:02:59 MDT
Total possible sunshine........... 11 hr 55 min 36 sec (715 min 36 sec)
Altitude of sun at 13:04:42 MDT... 48.68 degrees

Upper air data from rawinsonde observation taken on 09/28/2014 at 0600 MDT

Freezing level.................. 12970 ft MSL (8131 ft AGL)
Convective condensation level... 7982 ft MSL (3143 ft AGL)
Lifted condensation level....... 8909 ft MSL (4070 ft AGL)
Lifted index.................... -0.0
K index......................... +30.6

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  -64.4 -83.9   200   38   20   6.6   3.6   89.2 192.6    39.9      M    M
 45000  -62.4 -80.3   195   46   24  -0.2  -0.1   68.1 154.6    29.7      M    M
 40000  -56.7 -70.1   195   59   30   4.9   2.7   54.1 129.3    22.6      M    M
 38000  -53.2 -63.8   180   57   29   8.9   4.9   50.4 122.8    20.7      M    M
 36000  -47.2 -53.0   160   50   26   8.9   4.9   49.7 121.5    20.8      M    M
 34000  -42.2 -44.0   165   52   27   8.1   4.5   48.4 119.2    20.4      M    M
 32000  -38.5 -37.3   175   52   27   5.2   2.8   45.6 114.2    18.9      M    M
 30000  -32.7 -26.9   180   48   25   8.0   4.4   45.7 114.2    19.3      M    M
 29000  -30.3 -22.5   180   48   25   8.0   4.4   44.8 112.6    18.8      M    M
 28000  -28.0 -18.4   180   48   25   8.0   4.4   44.0 111.2    18.4      M    M
 27000  -25.6 -14.1   175   49   25   8.0   4.4   43.4 110.1    18.1      M    M
 26000  -23.2  -9.8   175   49   25   7.8   4.3   42.9 109.2    17.9      M    M
 25000  -21.2  -6.2   175   49   25   6.5   3.6   41.8 107.2    17.2      M    M
 24000  -19.3  -2.7   170   46   24   6.6   3.6   40.5 105.0    16.4      M    M
 23000  -17.3   0.9   165   43   22   6.6   3.6   39.4 103.0    15.6      M    M
 22000  -15.4   4.3   170   42   22   6.8   3.7   38.3 100.9    14.8      M    M
 21000  -13.8   7.2   175   42   22   4.9   2.7   36.7  98.1    13.6      M    M
 20000  -12.4   9.7   180   42   22   5.0   2.7   35.0  95.0    12.3      M    M
 19500  -11.0  12.2   185   39   20  10.1   5.5   34.1  93.5    11.6      M    M
 19000   -9.6  14.7   185   38   20   7.6   4.2   34.1  93.3    11.5      M    M
 18500   -8.7  16.3   185   38   19   6.4   3.5   33.4  92.1    11.0      M    M
 18000   -7.8  18.0   180   37   19   6.3   3.5   32.8  91.0    10.5      M    M
 17500   -6.9  19.6   180   37   19   6.3   3.5   32.2  89.9    10.0      M    M
 17000   -6.0  21.2   180   37   19   6.3   3.5   31.6  88.9     9.5      M    M
 16500   -5.1  22.8   175   36   19   5.9   3.2   31.1  88.0     9.0      M    M
 16000   -4.3  24.3   175   36   19   5.6   3.1   30.4  86.7     8.4      M    M
 15500   -3.5  25.7   175   36   19   5.6   3.1   29.7  85.4     7.8      M    M
 15000   -2.6  27.3   170   36   19   5.4   3.0   29.0  84.2     7.2      M    M
 14500   -1.9  28.6   170   36   19   4.9   2.7   28.2  82.7     6.5      M    M
 14000   -1.2  29.8   170   36   19   4.9   2.7   27.4  81.3     5.8      M    M
 13500   -0.5  31.1   170   37   19   5.4   3.0   26.6  79.8     5.0      M    M
 13000   -0.0  32.0   175   38   20   4.3   2.3   25.6  78.0     4.1      M    M
 12500    1.0  33.8   175   39   20   7.3   4.0   25.2  77.3     3.7      M    M
 12000    2.1  35.8   175   40   21   7.4   4.1   24.8  76.6     3.3      M    M
 11500    3.1  37.6   175   38   19   7.5   4.1   24.4  75.9     2.9      M    M
 11000    4.2  39.6   175   36   18   7.5   4.1   24.0  75.2     2.5      M    M
 10500    5.2  41.4   175   34   17   7.6   4.2   23.7  74.6     2.1      M    M
 10250    5.8  42.4   175   32   17   7.2   4.0   23.5  74.3     1.9      M    M
 10000    6.3  43.3   175   31   16   6.7   3.6   23.3  73.9     1.7      M    M
  9750    6.7  44.1   175   30   15   5.8   3.2   23.0  73.4     1.4      M    M
  9500    7.1  44.8   175   28   14   3.1   1.7   22.6  72.7     1.1      M    M
  9250    7.2  45.0   180   27   14   1.8   1.0   22.0  71.6     0.5      M    M
  9000    7.3  45.1   180   25   13   2.1   1.2   21.4  70.5    -0.1    274  1.4
  8750    7.5  45.5   175   22   11   2.2   1.2   20.8  69.4    -0.7    263  1.3
  8500    7.6  45.7   170   18    9   1.6   0.9   20.2  68.3    -1.3    251  1.3
  8250    7.8  46.0   155   15    8   4.2   2.3   19.6  67.3    -1.9    239  1.2
  8000    8.2  46.8   145   13    7   8.5   4.7   19.4  66.9    -2.1    218  1.1
  7750    8.9  48.0   135   11    6   8.7   4.7   19.3  66.7    -2.3    192  1.0
  7500    9.5  49.1   130    9    5   9.6   5.3   19.2  66.6    -2.4    166  0.8
  7250   10.1  50.2   120    8    4   5.8   3.2   19.2  66.5    -2.5    140  0.7
  7000   10.3  50.5   105    6    3   1.0   0.5   18.6  65.5    -3.1    128  0.6
  6750   10.3  50.5   090    5    3   0.6   0.3   17.9  64.3    -3.7    118  0.6
  6500   10.4  50.7   075    5    2   2.6   1.4   17.3  63.1    -4.4    109  0.6
  6250   10.7  51.3   055    4    2   5.8   3.2   16.9  62.3    -4.8     92  0.5
  6000   11.1  52.0   035    5    2   6.1   3.3   16.6  61.8    -5.1     72  0.4
  5750   11.5  52.7   025    4    2   6.0   3.3   16.3  61.3    -5.5     52  0.3
  5500   11.9  53.4   010    3    1   6.1   3.3   16.0  60.8    -5.8     32  0.2
  5250   12.4  54.3   340    2    1   5.8   3.2   15.7  60.3    -6.1     12  0.1
  5000   12.8  55.0   300    2    1   6.9   3.8   15.5  59.8    -6.4      M    M

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

           09/28/2014 at 0900 MDT          |       09/28/2014 at 1200 MDT
                                           |
K index... +30.7  LI... -1.6               | K index... +21.7  LI... +1.7
CAPE... +313.1  CIN... 0.0                 | CAPE... +9.4  CIN... -33.2
                                           |
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 -62.9 -81.2  205  40 21   1.4   0.8 | -61.4 -78.5  205  44 22   1.5   0.8
 45000 -60.0 -76.0  200  57 29   4.1   2.3 | -59.0 -74.2  205  65 33   2.0   1.1
 40000 -53.8 -64.8  190  57 29   4.1   2.2 | -56.0 -68.8  210  76 39   2.8   1.5
 38000 -51.5 -60.7  185  58 30   3.8   2.1 | -52.3 -62.1  205  69 36   6.5   3.5
 36000 -49.1 -56.4  180  61 31   3.8   2.1 | -48.4 -55.1  195  63 33   6.5   3.5
 34000 -45.3 -49.5  175  61 31   8.6   4.7 | -44.2 -47.6  185  58 30   7.5   4.1
 32000 -39.4 -38.9  175  58 30   8.7   4.8 | -39.1 -38.4  170  56 29   7.5   4.1
 30000 -34.4 -29.9  175  56 29   8.3   4.6 | -34.4 -29.9  165  57 29   8.1   4.4
 29000 -31.9 -25.4  175  56 29   8.3   4.6 | -31.9 -25.4  165  57 29   8.1   4.5
 28000 -29.4 -20.9  170  56 29   8.4   4.6 | -29.5 -21.1  165  58 30   8.2   4.5
 27000 -27.2 -17.0  170  55 28   7.1   3.9 | -27.4 -17.3  170  59 30   6.3   3.4
 26000 -25.1 -13.2  170  54 28   7.2   3.9 | -25.6 -14.1  170  60 31   6.3   3.4
 25000 -23.0  -9.4  175  53 27   7.2   3.9 | -23.7 -10.7  175  61 31   6.3   3.4
 24000 -20.9  -5.6  175  51 26   6.9   3.8 | -21.8  -7.2  175  62 32   7.0   3.9
 23000 -18.8  -1.8  175  49 25   7.0   3.8 | -19.7  -3.5  180  61 32   7.0   3.9
 22000 -16.8   1.8  175  47 24   7.0   3.8 | -17.6   0.3  180  61 31   7.0   3.8
 21000 -14.7   5.5  175  45 23   7.1   3.9 | -15.7   3.7  185  60 31   6.4   3.5
 20000 -12.6   9.3  175  41 21   7.1   3.9 | -13.8   7.2  185  59 30   6.4   3.5
 19500 -11.6  11.1  180  40 20   7.1   3.9 | -12.9   8.8  185  58 30   6.4   3.5
 19000 -10.6  12.9  180  38 20   7.1   3.9 | -11.9  10.6  190  58 30   6.5   3.6
 18500  -9.7  14.5  180  37 19   5.8   3.2 | -11.2  11.8  190  56 29   3.9   2.2
 18000  -8.8  16.2  180  35 18   5.9   3.2 | -10.6  12.9  190  54 28   4.2   2.3
 17500  -7.9  17.8  185  34 17   5.8   3.2 |  -9.9  14.2  195  51 26   6.1   3.4
 17000  -7.1  19.2  185  32 16   5.7   3.1 |  -8.8  16.2  195  49 25   7.1   3.9
 16500  -6.3  20.7  185  30 15   5.7   3.1 |  -7.8  18.0  195  46 24   6.7   3.7
 16000  -5.5  22.1  185  28 14   5.6   3.0 |  -7.1  19.2  195  45 23   3.0   1.6
 15500  -4.7  23.5  190  25 13   5.6   3.1 |  -6.4  20.5  200  45 23   4.6   2.5
 15000  -3.6  25.5  195  22 11   4.9   2.7 |  -5.4  22.3  200  42 22   6.9   3.8
 14500  -2.9  26.8  195  20 10   4.9   2.7 |  -4.4  24.1  200  39 20   6.8   3.7
 14000  -2.1  28.2  200  19 10   5.6   3.1 |  -3.6  25.5  205  37 19   5.2   2.9
 13500  -1.3  29.7  205  18  9   5.5   3.0 |  -2.8  27.0  205  35 18   5.2   2.9
 13000  -0.5  31.1  210  18  9   5.9   3.2 |  -1.9  28.6  205  34 17   6.7   3.7
 12500   0.3  32.5  210  18  9   5.7   3.1 |  -0.9  30.4  210  32 17   6.5   3.6
 12000   1.3  34.3  215  18  9   7.9   4.3 |   0.0  32.0  210  31 16   6.6   3.6
 11500   2.4  36.3  215  18  9   8.1   4.4 |   1.0  33.8  210  29 15   6.6   3.6
 11000   3.4  38.1  215  17  9   5.7   3.1 |   1.9  35.4  210  27 14   6.6   3.6
 10500   4.2  39.6  215  16  8   5.0   2.8 |   2.9  37.2  210  25 13   7.1   3.9
 10250   4.6  40.3  215  16  8   8.3   4.5 |   3.4  38.1  215  23 12   4.8   2.6
 10000   5.3  41.5  215  15  8   8.7   4.8 |   3.7  38.7  210  22 11   7.0   3.8
  9750   5.8  42.4  215  15  7   5.7   3.1 |   4.4  39.9  210  21 11  10.8   5.9
  9500   6.2  43.2  215  14  7   6.8   3.8 |   5.2  41.4  210  20 10  10.1   5.6
  9250   6.7  44.1  215  13  7   5.5   3.0 |   5.9  42.6  210  19 10   7.0   3.8
  9000   7.0  44.6  215  13  6   5.6   3.1 |   6.2  43.2  210  18  9   5.4   3.0
  8750   7.5  45.5  215  12  6   6.8   3.7 |   6.7  44.1  210  17  9   7.3   4.0
  8500   7.9  46.2  215  11  6   6.4   3.5 |   7.2  45.0  205  16  8   6.6   3.6
  8250   8.4  47.1  215  10  5   6.9   3.8 |   7.7  45.9  205  15  8   5.9   3.2
  8000   8.9  48.0  215   9  5   6.4   3.5 |   8.1  46.6  200  14  7   5.1   2.8
  7750   9.3  48.7  215   8  4   5.5   3.0 |   8.4  47.1  195  13  7   5.3   2.9
  7500   9.6  49.3  210   7  4   5.6   3.1 |   8.8  47.8  190  12  6   3.8   2.1
  7250  10.0  50.0  210   7  3   5.8   3.2 |   8.9  48.0  180  11  6   2.2   1.2
  7000  10.4  50.7  215   6  3   5.7   3.1 |   9.0  48.2  160  10  5   1.7   0.9
  6750  10.8  51.4  215   5  2   5.0   2.8 |   9.0  48.2  140  10  5   1.0   0.6
  6500  11.2  52.2  225   4  2   6.2   3.4 |   9.1  48.4  125  10  5   4.8   2.6
  6250  11.7  53.1  235   3  2   7.2   4.0 |   9.6  49.3  115   9  5   7.6   4.2
  6000  12.2  54.0  245   3  2   7.2   4.0 |  10.0  50.0  105   9  5   6.2   3.4
  5750  12.7  54.9  260   3  2   7.4   4.0 |  10.4  50.7  095   9  5   6.3   3.4
  5500  13.2  55.8  260   3  2   6.6   3.6 |  10.9  51.6  095   9  5   7.3   4.0
  5250  13.7  56.7  265   3  2   6.3   3.5 |  11.4  52.5  095   8  4   6.8   3.8
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/28/2014 at 1500 MDT          |       09/28/2014 at 1800 MDT
                                           |
K index... +12.0  LI... -1.4               | K index... +26.1  LI... -2.4
CAPE... +171.0  CIN... -4.3                | CAPE... +273.1  CIN... -11.4
                                           |
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 -60.9 -77.6  210  41 21   0.5   0.3 | -59.9 -75.8  220  36 19   1.0   0.5
 45000 -59.6 -75.3  210  66 34   2.8   1.5 | -58.1 -72.6  215  64 33   2.3   1.3
 40000 -55.5 -67.9  215  74 38   3.5   1.9 | -54.6 -66.3  215  81 42   2.1   1.1
 38000 -51.5 -60.7  210  76 39   6.9   3.8 | -51.3 -60.3  210  84 43   5.9   3.3
 36000 -47.3 -53.1  210  77 40   6.9   3.8 | -47.7 -53.9  210  86 44   5.9   3.3
 34000 -43.0 -45.4  210  78 40   7.4   4.1 | -43.8 -46.8  210  87 45   7.1   3.9
 32000 -38.0 -36.4  210  79 40   7.4   4.1 | -39.0 -38.2  210  87 45   7.1   3.9
 30000 -33.8 -28.8  210  77 40   6.7   3.7 | -35.1 -31.2  210  85 44   6.3   3.4
 29000 -31.8 -25.2  210  76 39   6.7   3.7 | -33.2 -27.8  210  83 42   6.3   3.4
 28000 -29.7 -21.5  210  74 38   6.7   3.7 | -31.3 -24.3  210  80 41   6.3   3.4
 27000 -27.8 -18.0  210  72 37   6.2   3.4 | -29.3 -20.7  210  78 40   6.9   3.8
 26000 -26.0 -14.8  205  68 35   6.2   3.4 | -27.3 -17.1  205  76 39   7.0   3.8
 25000 -24.1 -11.4  200  64 33   6.2   3.4 | -25.2 -13.4  205  74 38   7.0   3.8
 24000 -22.2  -8.0  200  62 32   6.6   3.6 | -23.2  -9.8  205  71 36   6.1   3.4
 23000 -20.3  -4.5  200  61 31   6.5   3.6 | -21.3  -6.3  205  66 34   6.2   3.4
 22000 -18.3  -0.9  200  60 31   6.5   3.6 | -19.4  -2.9  205  61 31   6.2   3.4
 21000 -16.4   2.5  195  58 30   6.1   3.3 | -17.6   0.3  200  57 29   6.2   3.4
 20000 -14.6   5.7  195  54 28   6.1   3.4 | -15.7   3.7  200  53 28   6.2   3.4
 19500 -13.7   7.3  190  52 27   6.1   3.4 | -14.8   5.4  200  52 27   6.2   3.4
 19000 -12.8   9.0  190  51 26   6.1   3.3 | -13.9   7.0  200  50 26   6.3   3.5
 18500 -11.7  10.9  190  50 26   8.6   4.7 | -13.0   8.6  195  49 25   5.5   3.0
 18000 -10.4  13.3  190  49 25   8.4   4.6 | -12.2  10.0  195  49 25   5.6   3.1
 17500  -9.2  15.4  190  49 25   5.2   2.9 | -11.4  11.5  195  48 25   5.8   3.2
 17000  -8.7  16.3  195  48 25   3.3   1.8 | -10.5  13.1  195  47 24   6.0   3.3
 16500  -8.3  17.1  200  47 24   3.5   1.9 |  -9.7  14.5  195  45 23   6.1   3.3
 16000  -7.5  18.5  200  45 23   6.2   3.4 |  -8.7  16.3  195  44 22   7.6   4.2
 15500  -6.2  20.8  205  42 22   5.8   3.2 |  -7.6  18.3  195  42 22   7.5   4.1
 15000  -5.4  22.3  205  39 20   5.5   3.0 |  -6.0  21.2  195  40 20   7.3   4.0
 14500  -4.6  23.7  205  36 18   5.7   3.1 |  -5.0  23.0  195  38 20   7.4   4.1
 14000  -3.8  25.2  210  33 17   6.5   3.5 |  -3.9  25.0  195  36 19   7.7   4.2
 13500  -2.9  26.8  210  30 16   6.5   3.5 |  -2.8  27.0  195  34 17   7.6   4.2
 13000  -1.9  28.6  205  27 14   7.9   4.3 |  -1.7  28.9  195  31 16   8.2   4.5
 12500  -0.9  30.4  205  25 13   7.9   4.3 |  -0.6  30.9  195  27 14   8.2   4.5
 12000   0.2  32.4  205  22 12   8.1   4.5 |   0.6  33.1  195  24 12   7.8   4.3
 11500   1.4  34.5  200  20 10   8.3   4.6 |   1.7  35.1  195  21 11   7.9   4.3
 11000   2.4  36.3  200  18  9   6.4   3.5 |   2.8  37.0  190  18  9   7.4   4.1
 10500   3.4  38.1  195  16  8   5.6   3.1 |   3.9  39.0  190  15  8   6.8   3.7
 10250   3.8  38.8  190  15  8  10.0   5.5 |   4.4  39.9  185  14  7   9.7   5.3
 10000   4.7  40.5  190  15  7  10.8   5.9 |   5.2  41.4  185  13  7  10.0   5.5
  9750   5.3  41.5  185  14  7   6.9   3.8 |   5.8  42.4  185  12  6   7.4   4.1
  9500   5.8  42.4  180  13  7   8.1   4.4 |   6.4  43.5  180  11  6   8.1   4.5
  9250   6.4  43.5  180  12  6   6.8   3.7 |   7.0  44.6  180  10  5   7.8   4.3
  9000   6.9  44.4  175  12  6   7.3   4.0 |   7.5  45.5  180   9  5   8.0   4.4
  8750   7.4  45.3  165  11  6   8.4   4.6 |   8.1  46.6  175   8  4   8.3   4.6
  8500   8.0  46.4  160  10  5   8.3   4.6 |   8.7  47.7  175   7  4   8.2   4.5
  8250   8.6  47.5  155   9  5   9.6   5.2 |   9.3  48.7  175   6  3   8.8   4.8
  8000   9.3  48.7  150   9  5   9.7   5.3 |  10.0  50.0  175   5  3   8.7   4.8
  7750  10.0  50.0  150   9  4   8.8   4.9 |  10.6  51.1  180   5  2   8.2   4.5
  7500  10.7  51.3  145   8  4   9.5   5.2 |  11.2  52.2  185   4  2   8.6   4.7
  7250  11.4  52.5  145   8  4  10.3   5.6 |  11.9  53.4  195   4  2   9.2   5.0
  7000  12.2  54.0  145   8  4  10.1   5.5 |  12.6  54.7  205   3  2   9.3   5.1
  6750  12.9  55.2  145   8  4   9.6   5.2 |  13.2  55.8  215   3  2   9.1   5.0
  6500  13.6  56.5  145   7  4  10.2   5.6 |  13.9  57.0  225   3  2   9.6   5.3
  6250  14.4  57.9  145   7  4  11.2   6.1 |  14.7  58.5  230   3  2  10.2   5.6
  6000  15.2  59.4  145   7  4  10.0   5.5 |  15.4  59.7  235   3  2   9.9   5.4
  5750  16.0  60.8  145   7  3  10.5   5.7 |  16.1  61.0  240   3  2   8.6   4.7
  5500  16.8  62.2  140   6  3  12.8   7.0 |  16.7  62.1  240   3  1   7.0   3.8
  5250  17.8  64.0  140   6  3  12.9   7.1 |  17.2  63.0  245   3  1   7.1   3.9
  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 0.000 sec
                   West Longitude: 108 deg 32 min 0.000 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  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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