Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 131232
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0532 MST Saturday, December 13, 2014

This forecast is for Saturday, December 13, 2014:

If the trigger temperature of 60.3 F/15.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5146 ft MSL (307 ft AGL)

Forecast maximum temperature................... 48.0 F/9.3 C
Time of trigger temperature.................... None
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................. None
Thermal soaring outlook for Sunday 12/14....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:24:44 / 16:52:09 MST
Total possible sunshine........... 9 hr 27 min 25 sec (567 min 25 sec)
Altitude of sun at 12:08:30 MST... 27.77 degrees

Upper air data from rawinsonde observation taken on 12/13/2014 at 0500 MST

Freezing level.................. 10145 ft MSL (5306 ft AGL)
Convective condensation level... 13314 ft MSL (8475 ft AGL)
Lifted condensation level....... 9953 ft MSL (5114 ft AGL)
Lifted index.................... +8.2
K index......................... +24.5

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  -57.3 -71.1   270   22   11   8.1   4.5  106.8 224.3    55.6      M    M
 45000  -62.0 -79.6   185   47   24 -10.6  -5.8   73.0 163.4    39.1      M    M
 40000  -57.2 -71.0   205   48   25   0.3   0.2   57.6 135.7    31.8      M    M
 38000  -55.2 -67.4   195   76   39   3.7   2.0   51.7 125.1    28.7      M    M
 36000  -53.9 -65.0   190   84   43   2.9   1.6   45.1 113.1    24.9      M    M
 34000  -51.7 -61.1   190   94   49  -0.3  -0.2   39.8 103.7    21.9      M    M
 32000  -47.6 -53.7   195   85   44   7.6   4.2   36.3  97.3    20.0      M    M
 30000  -43.4 -46.1   195   80   41   9.1   5.0   34.2  93.5    18.9      M    M
 29000  -40.6 -41.1   190   81   42   9.5   5.2   34.0  93.2    19.0      M    M
 28000  -37.9 -36.2   185   83   43   8.0   4.4   33.7  92.7    19.0      M    M
 27000  -35.5 -31.9   185   76   39   8.1   4.4   33.0  91.5    18.7      M    M
 26000  -33.2 -27.8   185   70   36   6.6   3.6   32.3  90.1    18.3      M    M
 25000  -31.9 -25.4   185   63   32   3.7   2.0   30.2  86.3    16.9      M    M
 24000  -30.5 -22.9   190   56   29   5.6   3.0   28.2  82.8    15.5      M    M
 23000  -28.2 -18.8   195   53   27   8.1   4.5   27.5  81.5    15.1      M    M
 22000  -25.8 -14.4   195   55   28   8.1   4.5   26.8  80.2    14.7      M    M
 21000  -23.4 -10.1   195   57   29   8.1   4.5   26.2  79.2    14.3      M    M
 20000  -21.1  -6.0   195   59   30   2.1   1.2   25.5  77.9    13.9      M    M
 19500  -20.6  -5.1   195   56   29   6.4   3.5   24.4  75.8    13.1      M    M
 19000  -19.8  -3.6   200   52   27   4.2   2.3   23.6  74.5    12.5      M    M
 18500  -19.4  -2.9   200   48   25   4.2   2.3   22.4  72.4    11.5      M    M
 18000  -18.3  -0.9   205   47   24   4.9   2.7   21.2  70.1    10.5      M    M
 17500  -17.5   0.5   210   48   25   5.0   2.8   20.4  68.7     9.9      M    M
 17000  -16.9   1.6   210   48   25   7.1   3.9   19.4  66.9     9.1      M    M
 16500  -15.5   4.1   205   47   24   8.8   4.8   19.4  67.0     9.1      M    M
 16000  -13.7   7.3   205   46   24  13.6   7.4   19.9  67.8     9.4      M    M
 15500  -12.2  10.0   205   45   23   8.6   4.7   20.1  68.1     9.6      M    M
 15000  -11.2  11.8   200   43   22   6.9   3.8   19.6  67.2     9.1      M    M
 14500  -10.2  13.6   200   42   22   6.8   3.7   19.1  66.4     8.7      M    M
 14000   -9.2  15.4   200   41   21   6.8   3.7   18.6  65.5     8.3      M    M
 13500   -8.2  17.2   200   39   20   6.8   3.7   18.1  64.6     7.9      M    M
 13000   -7.2  19.0   200   36   19   6.8   3.7   17.6  63.7     7.5      M    M
 12500   -6.2  20.8   200   34   18   6.7   3.7   17.2  62.9     7.0      M    M
 12000   -5.1  22.8   200   32   16   8.8   4.8   16.8  62.2     6.7      M    M
 11500   -3.8  25.2   200   29   15   9.1   5.0   16.7  62.0     6.7      M    M
 11000   -2.4  27.7   200   26   13   9.1   5.0   16.6  61.8     6.6      M    M
 10500   -1.0  30.2   195   23   12   8.9   4.9   16.5  61.6     6.5      M    M
 10250   -0.3  31.5   195   21   11   9.9   5.5   16.4  61.6     6.5      M    M
 10000    0.4  32.7   195   19   10  10.1   5.5   16.5  61.7     6.6      M    M
  9750    1.1  34.0   195   19   10   9.1   5.0   16.5  61.7     6.6      M    M
  9500    1.8  35.2   195   19   10   9.4   5.2   16.4  61.6     6.6      M    M
  9250    2.5  36.5   190   19   10   9.3   5.1   16.4  61.6     6.6      M    M
  9000    3.2  37.8   190   19   10   9.4   5.1   16.4  61.5     6.6      M    M
  8750    3.9  39.0   185   19   10   9.4   5.1   16.4  61.5     6.6      M    M
  8500    4.6  40.3   185   19   10   9.4   5.1   16.3  61.4     6.5      M    M
  8250    5.3  41.5   180   19   10   9.4   5.1   16.3  61.4     6.5      M    M
  8000    6.0  42.8   175   19   10   9.4   5.1   16.3  61.3     6.5      M    M
  7750    6.7  44.1   175   19   10   9.4   5.1   16.3  61.3     6.5      M    M
  7500    7.4  45.3   175   19   10   9.4   5.1   16.2  61.2     6.5      M    M
  7250    8.1  46.6   170   20   10   9.4   5.1   16.2  61.1     6.5      M    M
  7000    8.8  47.8   170   20   10   9.3   5.1   16.1  61.1     6.4      M    M
  6750    9.5  49.1   170   20   10   9.5   5.2   16.1  61.0     6.4      M    M
  6500   10.2  50.4   165   21   11   8.9   4.9   16.1  60.9     6.4      M    M
  6250   10.9  51.6   165   21   11  11.0   6.0   16.0  60.8     6.4      M    M
  6000   11.4  52.5   160   22   11  -4.7  -2.6   15.8  60.4     6.2      M    M
  5750   10.2  50.4   160   19   10 -23.9 -13.1   13.7  56.7     4.2      M    M
  5500    8.7  47.7   155   14    7 -11.5  -6.3   11.5  52.7     2.0      M    M
  5250    8.4  47.1   145   10    5  -1.4  -0.8   10.5  50.8     1.0      M    M
  5000    7.8  46.0   125    6    3 -16.2  -8.9    9.2  48.5    -0.3     30  0.2

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

           12/13/2014 at 0800 MST          |       12/13/2014 at 1100 MST
                                           |
K index... +15.9  LI... -0.2               | K index... +22.0  LI... +1.2
CAPE... +54.1  CIN... -8.4                 | CAPE... 0.0  CIN... -5.2
                                           |
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 -60.3 -76.5  220  29 15   1.9   1.1 | -59.7 -75.5  220  33 17   1.7   0.9
 45000 -57.4 -71.3  205  45 23   1.9   1.0 | -57.0 -70.6  210  50 26   1.9   1.0
 40000 -54.7 -66.5  205  58 30   1.7   0.9 | -54.0 -65.2  205  52 27   2.0   1.1
 38000 -53.7 -64.7  205  64 33   1.6   0.9 | -52.9 -63.2  200  56 29   1.5   0.8
 36000 -52.7 -62.9  200  71 37   1.6   0.9 | -52.0 -61.6  195  63 33   1.5   0.8
 34000 -51.5 -60.7  195  78 40   5.7   3.2 | -51.0 -59.8  190  71 36   4.3   2.3
 32000 -48.1 -54.6  190  72 37   5.6   3.1 | -48.1 -54.6  190  68 35   4.9   2.7
 30000 -44.6 -48.3  190  67 34   7.3   4.0 | -45.1 -49.2  190  65 34   6.7   3.7
 29000 -42.0 -43.6  190  65 34   7.1   3.9 | -42.5 -44.5  190  64 33   6.9   3.8
 28000 -39.8 -39.6  190  64 33   7.1   3.9 | -40.4 -40.7  190  64 33   7.0   3.8
 27000 -37.7 -35.9  190  62 32   7.5   4.1 | -38.3 -36.9  190  63 32   7.0   3.9
 26000 -35.3 -31.5  190  61 31   8.0   4.4 | -36.1 -33.0  190  61 32   7.3   4.0
 25000 -32.9 -27.2  195  59 30   8.0   4.4 | -33.9 -29.0  190  60 31   7.3   4.0
 24000 -30.5 -22.9  195  57 30   8.0   4.4 | -31.7 -25.1  190  59 30   7.4   4.0
 23000 -28.1 -18.6  195  56 29   8.2   4.5 | -29.2 -20.6  195  57 29   8.8   4.8
 22000 -25.6 -14.1  195  54 28   8.2   4.5 | -26.6 -15.9  195  55 28   8.8   4.8
 21000 -23.2  -9.8  195  53 27   6.9   3.8 | -24.0 -11.2  200  53 27   7.9   4.3
 20000 -21.4  -6.5  200  51 26   6.0   3.3 | -21.9  -7.4  205  50 26   6.9   3.8
 19500 -20.5  -4.9  200  50 26   6.0   3.3 | -20.9  -5.6  205  48 25   6.9   3.8
 19000 -19.6  -3.3  200  50 25   6.0   3.3 | -19.9  -3.8  205  47 24   6.8   3.8
 18500 -18.8  -1.8  205  49 25   6.1   3.4 | -18.8  -1.8  210  46 24   6.7   3.7
 18000 -17.8  -0.0  205  47 24   6.4   3.5 | -17.9  -0.2  210  45 23   6.3   3.5
 17500 -16.8   1.8  205  45 23   6.4   3.5 | -17.0   1.4  210  44 23   6.3   3.5
 17000 -15.9   3.4  205  43 22   6.4   3.5 | -16.0   3.2  205  43 22   7.1   3.9
 16500 -14.9   5.2  205  42 22   6.4   3.5 | -15.0   5.0  205  42 22   7.1   3.9
 16000 -14.0   6.8  205  41 21   6.7   3.7 | -13.9   7.0  205  41 21   6.4   3.5
 15500 -13.0   8.6  205  41 21   6.8   3.8 | -13.1   8.4  210  40 21   5.8   3.2
 15000 -12.0  10.4  210  40 21   6.9   3.8 | -12.2  10.0  210  39 20   5.9   3.3
 14500 -10.9  12.4  210  39 20   7.1   3.9 | -11.3  11.7  210  38 20   6.6   3.6
 14000  -9.4  15.1  210  38 20   7.3   4.0 |  -9.9  14.2  210  37 19   6.3   3.5
 13500  -8.3  17.1  210  38 19   7.4   4.0 |  -9.0  15.8  210  37 19   6.2   3.4
 13000  -7.3  18.9  210  37 19   7.5   4.1 |  -8.2  17.2  210  37 19   6.5   3.5
 12500  -6.2  20.8  210  36 19   7.7   4.2 |  -7.2  19.0  210  35 18   6.8   3.7
 12000  -5.1  22.8  210  36 18   7.6   4.2 |  -6.2  20.8  215  34 17   6.8   3.8
 11500  -4.0  24.8  210  35 18   7.5   4.1 |  -5.2  22.6  215  32 17   6.9   3.8
 11000  -3.0  26.6  210  34 17   7.1   3.9 |  -4.2  24.4  215  31 16   6.5   3.5
 10500  -2.0  28.4  215  32 16   6.1   3.3 |  -3.3  26.1  215  29 15   5.3   2.9
 10250  -1.5  29.3  215  31 16   9.4   5.1 |  -2.9  26.8  215  28 14   8.8   4.8
 10000  -0.7  30.7  215  30 15   9.9   5.4 |  -2.1  28.2  215  27 14   9.4   5.2
  9750  -0.2  31.6  215  30 15   7.1   3.9 |  -1.6  29.1  215  26 13   6.2   3.4
  9500   0.4  32.7  215  30 15   7.7   4.2 |  -1.1  30.0  215  25 13   7.2   4.0
  9250   0.9  33.6  210  29 15   8.1   4.4 |  -0.6  30.9  215  24 12   6.5   3.6
  9000   1.5  34.7  210  29 15   8.5   4.7 |  -0.2  31.6  215  23 12   6.3   3.4
  8750   2.1  35.8  210  29 15   8.3   4.6 |   0.3  32.5  215  21 11   6.6   3.6
  8500   2.7  36.9  210  28 14   8.3   4.5 |   0.8  33.4  220  20 10   6.6   3.6
  8250   3.4  38.1  210  27 14   8.7   4.8 |   1.2  34.2  220  18  9   6.5   3.6
  8000   4.0  39.2  205  26 13   8.5   4.7 |   1.7  35.1  225  16  8   5.7   3.1
  7750   4.6  40.3  205  25 13   7.4   4.1 |   2.1  35.8  225  14  7   4.8   2.6
  7500   5.2  41.4  200  24 13   7.2   4.0 |   2.4  36.3  225  12  6   4.6   2.5
  7250   5.7  42.3  195  24 12   5.9   3.2 |   2.8  37.0  225  10  5   5.5   3.0
  7000   6.1  43.0  190  22 12   4.1   2.3 |   3.3  37.9  230   9  4   6.5   3.6
  6750   6.4  43.5  185  21 11   4.1   2.3 |   3.8  38.8  230   7  4   6.6   3.6
  6500   6.7  44.1  180  20 10   0.1   0.0 |   4.3  39.7  230   6  3   8.3   4.6
  6250   6.5  43.7  175  19 10  -4.9  -2.7 |   5.1  41.2  235   5  3  10.6   5.8
  6000   6.1  43.0  165  17  9  -5.4  -3.0 |   5.9  42.6  235   5  3  10.5   5.8
  5750   5.7  42.3  155  14  7  -7.7  -4.2 |   6.6  43.9  240   5  2   9.2   5.0
  5500   4.9  40.8  140  10  5 -12.0  -6.6 |   7.3  45.1  240   4  2   8.7   4.8
  5250   3.9  39.0  135   8  4 -14.2  -7.8 |   7.9  46.2  245   4  2   9.5   5.2
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/13/2014 at 1400 MST          |       12/13/2014 at 1700 MST
                                           |
K index... +24.9  LI... +0.9               | K index... +21.0  LI... +2.2
CAPE... +0.8  CIN... M                     | CAPE... 0.0  CIN... M
                                           |
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 -58.6 -73.5  225  29 15   1.1   0.6 | -57.9 -72.2  240  27 14   1.6   0.9
 45000 -56.9 -70.4  215  47 24   1.8   1.0 | -55.5 -67.9  215  43 22   1.6   0.9
 40000 -53.1 -63.6  210  49 25   2.5   1.4 | -52.6 -62.7  205  42 22   1.9   1.0
 38000 -51.9 -61.4  205  52 27   1.2   0.7 | -51.5 -60.7  200  44 23   1.8   1.0
 36000 -51.2 -60.2  200  59 30   1.2   0.7 | -50.4 -58.7  200  48 25   1.8   1.0
 34000 -50.5 -58.9  195  66 34   2.7   1.5 | -49.3 -56.7  200  52 27   2.0   1.1
 32000 -48.2 -54.8  190  65 33   3.8   2.1 | -47.9 -54.2  195  55 28   2.3   1.3
 30000 -45.9 -50.6  185  64 33   5.3   2.9 | -46.5 -51.7  190  59 30   3.3   1.8
 29000 -43.5 -46.3  185  61 32   6.3   3.5 | -44.6 -48.3  190  57 29   5.3   2.9
 28000 -41.6 -42.9  185  59 31   6.3   3.5 | -43.0 -45.4  190  55 28   5.3   2.9
 27000 -39.7 -39.5  190  57 30   6.3   3.5 | -41.5 -42.7  190  53 27   4.9   2.7
 26000 -37.5 -35.5  190  56 29   7.8   4.3 | -39.2 -38.6  190  51 26   8.6   4.7
 25000 -35.1 -31.2  190  56 29   7.8   4.3 | -36.6 -33.9  190  50 26   8.6   4.7
 24000 -32.8 -27.0  195  55 28   7.8   4.3 | -34.0 -29.2  195  49 25   8.6   4.7
 23000 -30.3 -22.5  195  53 27   8.5   4.7 | -31.5 -24.7  195  47 24   8.6   4.7
 22000 -27.8 -18.0  200  50 26   8.5   4.7 | -28.9 -20.0  195  44 23   8.6   4.7
 21000 -25.3 -13.5  205  48 25   8.4   4.6 | -26.3 -15.3  195  41 21   8.5   4.7
 20000 -22.9  -9.2  200  45 23   8.0   4.4 | -23.9 -11.0  195  38 19   8.0   4.4
 19500 -21.8  -7.2  200  43 22   8.0   4.4 | -22.7  -8.9  195  35 18   8.1   4.4
 19000 -20.6  -5.1  200  42 21   8.0   4.4 | -21.6  -6.9  195  33 17   8.1   4.4
 18500 -19.4  -2.9  200  40 21   7.9   4.4 | -20.4  -4.7  195  31 16   8.1   4.5
 18000 -18.3  -0.9  200  40 21   6.9   3.8 | -19.2  -2.6  195  30 15   7.1   3.9
 17500 -17.3   0.9  200  41 21   7.0   3.8 | -18.2  -0.8  200  29 15   7.2   4.0
 17000 -16.3   2.7  200  41 21   6.9   3.8 | -17.1   1.2  200  27 14   7.2   4.0
 16500 -15.3   4.5  200  39 20   6.8   3.8 | -16.1   3.0  200  26 13   7.2   4.0
 16000 -14.3   6.3  200  38 20   6.8   3.7 | -15.0   5.0  200  24 13   7.3   4.0
 15500 -13.3   8.1  200  38 20   6.8   3.7 | -13.9   7.0  200  22 12   7.6   4.2
 15000 -12.3   9.9  200  38 20   6.8   3.7 | -12.8   9.0  195  20 11   7.6   4.2
 14500 -11.4  11.5  200  38 19   6.2   3.4 | -11.7  10.9  195  18  9   7.4   4.0
 14000 -10.0  14.0  200  37 19   6.4   3.5 | -10.6  12.9  195  16  8   7.5   4.1
 13500  -9.1  15.6  200  35 18   6.5   3.6 |  -9.2  15.4  200  12  6   5.6   3.1
 13000  -8.1  17.4  200  34 17   6.4   3.5 |  -8.4  16.9  205   9  5   5.4   3.0
 12500  -7.2  19.0  200  30 16   6.2   3.4 |  -7.7  18.1  220   6  3   4.5   2.4
 12000  -6.3  20.7  200  27 14   6.3   3.4 |  -7.1  19.2  250   5  2   4.5   2.5
 11500  -5.4  22.3  200  23 12   6.4   3.5 |  -6.4  20.5  280   5  3   4.2   2.3
 11000  -4.5  23.9  200  18  9   5.8   3.2 |  -5.8  21.6  300   7  4   4.1   2.3
 10500  -3.8  25.2  205  14  7   3.7   2.0 |  -5.3  22.5  310  10  5   3.5   1.9
 10250  -3.5  25.7  205  12  6   5.2   2.8 |  -5.0  23.0  310  11  6   3.7   2.0
 10000  -3.1  26.4  210  10  5   6.4   3.5 |  -4.7  23.5  310  12  6   4.7   2.6
  9750  -2.7  27.1  210   9  5   4.7   2.6 |  -4.3  24.3  310  13  7   4.9   2.7
  9500  -2.4  27.7  215   8  4   4.0   2.2 |  -4.0  24.8  310  14  7   4.6   2.5
  9250  -2.1  28.2  225   7  3   4.1   2.3 |  -3.6  25.5  310  15  8   4.4   2.4
  9000  -1.8  28.8  230   6  3   4.0   2.2 |  -3.3  26.1  310  16  8   5.4   3.0
  8750  -1.5  29.3  245   5  3   4.1   2.3 |  -2.9  26.8  310  16  8   5.8   3.2
  8500  -1.2  29.8  265   5  3   4.2   2.3 |  -2.5  27.5  305  16  8   5.1   2.8
  8250  -0.9  30.4  280   6  3   4.2   2.3 |  -2.1  28.2  305  17  9   5.4   2.9
  8000  -0.6  30.9  290   7  3   3.5   1.9 |  -1.7  28.9  305  17  9   5.4   2.9
  7750  -0.3  31.5  295   8  4   2.7   1.5 |  -1.3  29.7  300  16  8   5.0   2.7
  7500  -0.2  31.6  300   9  5   2.2   1.2 |  -1.0  30.2  300  15  8   4.9   2.7
  7250   0.0  32.0  300  11  5   3.6   2.0 |  -0.6  30.9  300  15  8   4.5   2.5
  7000   0.4  32.7  305  11  6   5.3   2.9 |  -0.3  31.5  295  13  7   3.8   2.1
  6750   0.7  33.3  305  11  6   5.5   3.0 |  -0.1  31.8  295  12  6   3.5   1.9
  6500   1.2  34.2  305  12  6   7.0   3.8 |   0.1  32.2  295  10  5   3.5   1.9
  6250   1.8  35.2  305  12  6   8.9   4.9 |   0.4  32.7  295   8  4   4.2   2.3
  6000   2.5  36.5  305  11  6   9.5   5.2 |   0.7  33.3  295   7  4   4.5   2.5
  5750   3.1  37.6  305  10  5   8.9   4.9 |   1.1  34.0  290   5  3   5.5   3.0
  5500   3.8  38.8  305  10  5   9.2   5.0 |   1.5  34.7  290   4  2   6.2   3.4
  5250   4.5  40.1  305   9  5  10.1   5.5 |   1.9  35.4  290   4  2   5.7   3.1
  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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