Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 221220
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0620 MDT Friday, August 22, 2014

This forecast is for Friday, August 22, 2014:

If the trigger temperature of 77.1 F/25.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 752 ft/min (3.8 m/s)
   Maximum height of thermals.................. 15401 ft MSL (10562 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1100 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................. 9098 ft MSL (4259 ft AGL)
Thermal soaring outlook for Saturday 08/23..... Good

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

Remarks...

Sunrise/Sunset.................... 06:33:46 / 20:00:44 MDT
Total possible sunshine........... 13 hr 26 min 59 sec (806 min 59 sec)
Altitude of sun at 13:16:52 MDT... 62.48 degrees

Upper air data from rawinsonde observation taken on 08/22/2014 at 0600 MDT

Freezing level.................. 13852 ft MSL (9013 ft AGL)
Convective condensation level... 13308 ft MSL (8469 ft AGL)
Lifted condensation level....... 14005 ft MSL (9165 ft AGL)
Lifted index.................... -0.5
K index......................... +29.4

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  -61.1 -78.0   225   29   15   4.1   2.3   92.8 199.1    37.4      M    M
 45000  -60.1 -76.2   225   51   26  -4.8  -2.7   70.1 158.2    26.0      M    M
 40000  -52.8 -63.0   210   84   43   6.9   3.8   58.7 137.7    20.2      M    M
 38000  -49.1 -56.4   205   75   39   4.9   2.7   55.5 131.9    18.5      M    M
 36000  -46.2 -51.2   205   58   30   5.7   3.1   51.3 124.3    16.1      M    M
 34000  -41.3 -42.3   190   60   31   9.1   5.0   48.8 119.9    14.7      M    M
 32000  -36.1 -33.0   195   56   29  10.3   5.6   47.9 118.3    14.5      M    M
 30000  -31.4 -24.5   200   57   29   9.2   5.0   46.4 115.5    13.6      M    M
 29000  -29.3 -20.7   200   53   28   7.3   4.0   45.4 113.7    13.0      M    M
 28000  -27.0 -16.6   205   50   26   7.7   4.2   44.6 112.2    12.5      M    M
 27000  -24.9 -12.8   210   47   24   8.1   4.4   43.6 110.4    11.8      M    M
 26000  -22.5  -8.5   210   44   23   7.6   4.2   43.0 109.3    11.4      M    M
 25000  -20.2  -4.4   215   41   21   8.1   4.5   42.2 108.0    11.0      M    M
 24000  -18.7  -1.7   215   39   20   6.6   3.6   40.6 105.0     9.7      M    M
 23000  -16.2   2.8   215   36   19   5.2   2.8   40.0 104.0     9.4      M    M
 22000  -15.0   5.0   215   34   18   8.6   4.7   38.1 100.5     7.7      M    M
 21000  -12.7   9.1   220   32   17   6.1   3.3   37.3  99.1     7.1      M    M
 20000  -10.9  12.4   220   30   16   6.1   3.4   36.0  96.8     6.1      M    M
 19500  -10.1  13.8   220   27   14   6.1   3.3   35.3  95.6     5.5      M    M
 19000   -9.1  15.6   225   23   12   8.7   4.8   34.8  94.6     5.0      M    M
 18500   -7.7  18.1   220   17    9   5.3   2.9   33.9  93.0     4.2      M    M
 18000   -7.0  19.4   210   14    7   5.2   2.8   33.1  91.5     3.5      M    M
 17500   -6.3  20.7   195   12    6   5.3   2.9   32.3  90.2     2.8      M    M
 17000   -5.6  21.9   180   11    6   4.3   2.3   31.5  88.7     2.0      M    M
 16500   -5.0  23.0   190   10    5   4.3   2.4   30.6  87.0     1.2      M    M
 16000   -4.3  24.3   200   10    5   3.4   1.9   29.7  85.4     0.4      M    M
 15500   -3.3  26.1   205    8    4  10.0   5.5   29.3  84.7     0.0      M    M
 15000   -2.3  27.9   215    7    4   6.1   3.4   28.8  83.8    -0.5    910  4.6
 14500   -1.4  29.5   230    7    4   6.3   3.5   28.2  82.7    -1.0    868  4.4
 14000   -0.2  31.6   240    7    4   9.0   4.9   27.9  82.2    -1.3    819  4.2
 13500    1.1  34.0   230    7    4   8.8   4.8   27.7  81.9    -1.5    765  3.9
 13000    2.4  36.3   225    8    4   8.8   4.8   27.6  81.6    -1.7    711  3.6
 12500    3.7  38.7   220    8    4   8.8   4.8   27.4  81.4    -1.8    658  3.3
 12000    4.9  40.8   215    9    5   8.8   4.8   27.3  81.1    -1.9    604  3.1
 11500    6.2  43.2   205   10    5   8.8   4.8   27.1  80.8    -2.1    550  2.8
 11000    7.5  45.5   195   11    5   8.8   4.8   26.9  80.5    -2.3    496  2.5
 10500    8.8  47.8   185   12    6   8.9   4.9   26.8  80.2    -2.5    443  2.2
 10250    9.5  49.1   180   12    6   9.7   5.3   26.7  80.1    -2.5    415  2.1
 10000   10.3  50.5   175   12    6   9.9   5.4   26.8  80.2    -2.5    385  2.0
  9750   11.0  51.8   170   12    6   8.5   4.7   26.7  80.1    -2.6    357  1.8
  9500   11.5  52.7   165   13    7   7.7   4.2   26.6  79.8    -2.7    333  1.7
  9250   12.1  53.8   160   13    7   7.9   4.3   26.4  79.6    -2.9    308  1.6
  9000   12.7  54.9   155   14    7   7.8   4.3   26.3  79.3    -3.0    284  1.4
  8750   13.2  55.8   155   14    7   7.9   4.3   26.2  79.1    -3.2    259  1.3
  8500   13.8  56.8   150   15    8   7.9   4.3   26.0  78.8    -3.4    234  1.2
  8250   14.4  57.9   150   15    8   7.9   4.3   25.9  78.5    -3.5    210  1.1
  8000   15.0  59.0   145   16    8   7.9   4.3   25.7  78.3    -3.7    185  0.9
  7750   15.5  59.9   150   16    8   7.8   4.3   25.6  78.0    -3.9    161  0.8
  7500   16.1  61.0   155   16    8   8.1   4.4   25.4  77.8    -4.0    136  0.7
  7250   16.7  62.1   160   16    8   7.0   3.8   25.3  77.5    -4.2    111  0.6
  7000   17.0  62.6   165   16    8   2.9   1.6   24.9  76.9    -4.6     93  0.5
  6750   17.1  62.8   160   18    9   2.6   1.4   24.3  75.8    -5.2     83  0.4
  6500   17.5  63.5   155   21   11   7.3   4.0   24.0  75.1    -5.6     65  0.3
  6250   18.1  64.6   150   23   12   9.1   5.0   23.9  75.0    -5.7     39  0.2
  6000   18.7  65.7   145   26   13   8.6   4.7   23.8  74.8    -5.8     13  0.1
  5750   19.4  66.9   145   24   12   8.7   4.8   23.7  74.7    -5.9      M    M
  5500   20.0  68.0   140   20   10   8.8   4.8   23.6  74.5    -6.1      M    M
  5250   20.6  69.1   135   16    8   8.5   4.7   23.6  74.4    -6.2      M    M
  5000   21.0  69.8   125   12    6  -2.4  -1.3   23.2  73.7    -6.6      M    M

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

           08/22/2014 at 0900 MDT          |       08/22/2014 at 1200 MDT
                                           |
K index... +27.5  LI... -0.7               | K index... +26.4  LI... -0.9
CAPE... +26.3  CIN... -12.6                | CAPE... +131.0  CIN... -13.9
                                           |
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 -62.1 -79.8  225  29 15   2.2   1.2 | -61.5 -78.7  220  29 15   2.0   1.1
 45000 -58.1 -72.6  215  46 24   3.5   1.9 | -57.8 -72.0  210  50 26   3.0   1.7
 40000 -52.7 -62.9  210  71 37   6.0   3.3 | -52.9 -63.2  205  77 40   6.2   3.4
 38000 -49.1 -56.4  210  67 35   5.9   3.2 | -49.3 -56.7  205  77 40   6.1   3.3
 36000 -45.6 -50.1  210  63 32   5.9   3.2 | -45.6 -50.1  200  77 40   6.1   3.4
 34000 -41.3 -42.3  210  54 28   7.5   4.1 | -41.2 -42.2  205  70 36   7.7   4.2
 32000 -36.8 -34.2  210  45 23   7.5   4.1 | -36.0 -32.8  205  60 31   7.7   4.2
 30000 -31.4 -24.5  210  40 21   8.2   4.5 | -31.1 -24.0  210  54 28   8.2   4.5
 29000 -29.0 -20.2  210  39 20   8.2   4.5 | -28.6 -19.5  210  50 26   8.2   4.5
 28000 -26.5 -15.7  210  38 20   7.5   4.1 | -26.2 -15.2  210  47 24   7.7   4.2
 27000 -24.5 -12.1  210  36 19   6.7   3.7 | -24.0 -11.2  210  44 23   7.2   3.9
 26000 -22.5  -8.5  210  35 18   6.8   3.7 | -21.9  -7.4  210  40 21   7.2   4.0
 25000 -20.6  -5.1  210  33 17   6.9   3.8 | -19.8  -3.6  210  37 19   7.3   4.0
 24000 -18.4  -1.1  210  31 16   7.4   4.1 | -17.6   0.3  210  35 18   7.2   3.9
 23000 -16.2   2.8  215  30 16   7.4   4.1 | -15.5   4.1  210  33 17   7.2   4.0
 22000 -14.0   6.8  215  29 15   7.5   4.1 | -13.4   7.9  210  32 16   7.3   4.0
 21000 -12.2  10.0  215  28 14   6.1   3.3 | -11.5  11.3  215  30 15   6.5   3.6
 20000 -10.4  13.3  215  27 14   6.1   3.4 |  -9.6  14.7  215  28 14   6.6   3.6
 19500  -9.5  14.9  215  26 14   6.1   3.4 |  -8.6  16.5  215  27 14   6.6   3.6
 19000  -8.6  16.5  215  26 13   6.2   3.4 |  -7.7  18.1  215  26 13   6.4   3.5
 18500  -7.7  18.1  220  26 13   6.3   3.4 |  -6.8  19.8  215  25 13   6.3   3.4
 18000  -6.8  19.8  220  25 13   6.3   3.5 |  -5.9  21.4  215  24 12   6.2   3.4
 17500  -5.9  21.4  220  25 13   6.5   3.6 |  -5.0  23.0  215  23 12   5.6   3.1
 17000  -5.0  23.0  225  25 13   6.6   3.6 |  -4.2  24.4  220  22 11   5.7   3.1
 16500  -4.0  24.8  225  25 13   6.2   3.4 |  -3.4  25.9  220  21 11   5.4   2.9
 16000  -3.1  26.4  225  25 13   6.1   3.3 |  -2.6  27.3  220  21 11   5.3   2.9
 15500  -2.3  27.9  225  24 13   6.2   3.4 |  -1.9  28.6  220  20 10   5.3   2.9
 15000  -1.4  29.5  225  23 12   6.3   3.4 |  -0.7  30.7  220  19 10   5.5   3.0
 14500  -0.1  31.8  230  21 11   5.9   3.2 |   0.1  32.2  220  18  9   6.0   3.3
 14000   0.7  33.3  225  19 10   5.8   3.2 |   1.0  33.8  220  17  9   6.2   3.4
 13500   1.5  34.7  225  17  9   6.1   3.3 |   1.9  35.4  220  16  8   6.1   3.4
 13000   2.4  36.3  220  15  8   6.4   3.5 |   2.7  36.9  220  15  8   5.9   3.2
 12500   3.3  37.9  215  14  7   6.2   3.4 |   3.5  38.3  220  14  7   6.1   3.4
 12000   4.1  39.4  210  12  6   5.5   3.0 |   4.5  40.1  220  13  7   6.9   3.8
 11500   4.9  40.8  200  11  6   5.6   3.1 |   5.4  41.7  220  12  6   7.0   3.8
 11000   5.8  42.4  190  10  5   5.5   3.0 |   6.5  43.7  220  11  5   7.3   4.0
 10500   6.6  43.9  175  10  5   2.5   1.4 |   7.6  45.7  215   9  5   3.6   2.0
 10250   6.7  44.1  170  10  5   3.7   2.0 |   7.7  45.9  215   9  5   4.1   2.2
 10000   7.3  45.1  165   9  5   9.1   5.0 |   8.3  46.9  210   9  4   9.5   5.2
  9750   7.9  46.2  160   9  5   8.6   4.7 |   8.9  48.0  205   8  4   8.3   4.6
  9500   8.6  47.5  150   9  5   7.4   4.1 |   9.5  49.1  195   8  4   7.7   4.2
  9250   9.0  48.2  145   9  5   5.5   3.0 |  10.0  50.0  195   8  4   6.0   3.3
  9000   9.4  48.9  145   9  4   6.4   3.5 |  10.4  50.7  190   8  4   6.7   3.6
  8750  10.0  50.0  140   8  4   7.4   4.1 |  10.9  51.6  185   8  4   7.2   3.9
  8500  10.5  50.9  135   8  4   6.0   3.3 |  11.4  52.5  180   7  4   7.1   3.9
  8250  10.8  51.4  135   8  4   4.8   2.7 |  11.9  53.4  180   6  3   7.1   3.9
  8000  11.2  52.2  135   8  4   5.1   2.8 |  12.4  54.3  180   6  3   7.6   4.2
  7750  11.5  52.7  135   8  4   4.8   2.6 |  13.0  55.4  175   5  3   8.0   4.4
  7500  11.8  53.2  135   8  4   4.2   2.3 |  13.6  56.5  175   5  2   9.3   5.1
  7250  12.1  53.8  135   7  4   3.9   2.1 |  14.3  57.7  180   4  2  10.3   5.7
  7000  12.3  54.1  130   7  3   3.6   2.0 |  15.1  59.2  180   4  2  10.3   5.6
  6750  12.6  54.7  130   6  3   5.5   3.0 |  15.8  60.4  180   4  2  10.8   6.0
  6500  13.1  55.6  125   5  3   8.1   4.4 |  16.6  61.9  185   4  2  10.8   5.9
  6250  13.6  56.5  120   5  2   8.1   4.5 |  17.4  63.3  185   4  2  11.1   6.1
  6000  14.2  57.6  115   4  2   8.2   4.5 |  18.2  64.8  185   4  2  10.0   5.5
  5750  14.7  58.5  110   3  2   9.6   5.3 |  19.0  66.2  190   4  2  12.2   6.7
  5500  15.5  59.9  110   3  2  10.7   5.9 |  20.1  68.2  190   4  2  15.4   8.5
  5250  16.3  61.3  110   3  2   9.9   5.4 |  21.1  70.0  190   4  2  12.9   7.1
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/22/2014 at 1500 MDT          |       08/22/2014 at 1800 MDT
                                           |
K index... +28.3  LI... -1.6               | K index... +30.4  LI... -2.2
CAPE... +259.3  CIN... -10.6               | CAPE... +370.5  CIN... -7.5
                                           |
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 -62.1 -79.8  210  29 15   2.1   1.2 | -62.1 -79.8  210  31 16   1.5   0.8
 45000 -58.5 -73.3  205  52 27   2.7   1.5 | -58.7 -73.7  200  47 24   4.2   2.3
 40000 -53.8 -64.8  195  78 40   7.9   4.3 | -52.2 -62.0  190  60 31   6.4   3.5
 38000 -49.1 -56.4  190  72 37   7.8   4.3 | -48.4 -55.1  185  60 31   6.3   3.5
 36000 -44.4 -47.9  180  68 35   7.8   4.3 | -44.6 -48.3  180  60 31   6.3   3.5
 34000 -39.6 -39.3  185  66 34   8.1   4.4 | -40.3 -40.5  185  55 28   7.5   4.1
 32000 -34.1 -29.4  190  65 33   8.1   4.4 | -35.8 -32.4  190  49 25   7.5   4.1
 30000 -30.0 -22.0  195  60 31   6.6   3.6 | -30.8 -23.4  195  38 19   7.4   4.1
 29000 -28.0 -18.4  200  57 30   6.6   3.6 | -28.6 -19.5  200  32 17   7.4   4.1
 28000 -26.0 -14.8  200  55 28   6.8   3.7 | -26.4 -15.5  205  27 14   7.3   4.0
 27000 -23.9 -11.0  205  49 25   7.0   3.8 | -24.3 -11.7  210  25 13   7.0   3.8
 26000 -21.9  -7.4  205  44 23   7.0   3.8 | -22.3  -8.1  210  23 12   7.0   3.8
 25000 -19.8  -3.6  210  39 20   7.0   3.8 | -20.2  -4.4  210  22 11   7.0   3.8
 24000 -17.7   0.1  215  36 18   7.1   3.9 | -18.1  -0.6  215  20 11   7.2   3.9
 23000 -15.6   3.9  215  34 18   7.1   3.9 | -15.9   3.4  215  20 10   7.2   4.0
 22000 -13.5   7.7  215  32 17   7.1   3.9 | -13.8   7.2  220  19 10   7.3   4.0
 21000 -11.4  11.5  215  30 15   6.8   3.7 | -11.8  10.8  220  19 10   6.5   3.6
 20000  -9.5  14.9  220  27 14   6.9   3.8 |  -9.9  14.2  225  19 10   6.5   3.6
 19500  -8.5  16.7  220  26 13   6.9   3.8 |  -9.0  15.8  225  19 10   6.5   3.6
 19000  -7.5  18.5  220  25 13   6.4   3.5 |  -8.0  17.6  225  19 10   6.3   3.5
 18500  -6.6  20.1  220  25 13   6.1   3.4 |  -7.1  19.2  230  19 10   6.2   3.4
 18000  -5.7  21.7  220  24 12   6.1   3.4 |  -6.2  20.8  230  19 10   6.3   3.4
 17500  -4.9  23.2  220  24 12   5.6   3.0 |  -5.3  22.5  230  20 10   5.7   3.1
 17000  -4.1  24.6  220  23 12   5.6   3.1 |  -4.5  23.9  230  20 10   5.8   3.2
 16500  -3.3  26.1  220  23 12   5.6   3.1 |  -3.7  25.3  230  20 10   5.6   3.1
 16000  -2.5  27.5  220  23 12   5.6   3.1 |  -2.9  26.8  225  21 11   5.5   3.0
 15500  -1.7  28.9  220  22 12   5.7   3.1 |  -2.1  28.2  225  21 11   5.7   3.1
 15000  -0.5  31.1  220  22 11   5.9   3.2 |  -0.8  30.6  220  21 11   6.5   3.6
 14500   0.3  32.5  220  22 11   6.5   3.6 |   0.1  32.2  215  21 11   7.3   4.0
 14000   1.3  34.3  215  21 11   7.0   3.8 |   1.2  34.2  215  21 11   8.0   4.4
 13500   2.3  36.1  215  20 10   7.3   4.0 |   2.3  36.1  210  20 10   8.0   4.4
 13000   3.4  38.1  215  19 10   7.7   4.2 |   3.5  38.3  210  19 10   7.7   4.2
 12500   4.5  40.1  215  17  9   7.5   4.1 |   4.6  40.3  210  18  9   7.7   4.2
 12000   5.4  41.7  210  15  8   6.5   3.5 |   5.6  42.1  210  17  9   6.7   3.7
 11500   6.4  43.5  210  13  7   6.6   3.6 |   6.5  43.7  210  16  8   6.8   3.7
 11000   7.3  45.1  210  11  6   6.7   3.7 |   7.5  45.5  210  14  7   6.6   3.6
 10500   8.3  46.9  210  10  5   4.0   2.2 |   8.4  47.1  205  13  7   9.2   5.1
 10250   8.5  47.3  210   9  5   5.5   3.0 |   9.2  48.6  205  12  6  11.3   6.2
 10000   9.2  48.6  210   8  4  10.3   5.7 |  10.0  50.0  205  12  6   9.2   5.1
  9750   9.9  49.8  215   7  4   9.3   5.1 |  10.7  51.3  205  11  6   9.9   5.5
  9500  10.6  51.1  215   6  3   8.6   4.7 |  11.4  52.5  200  11  5   9.2   5.1
  9250  11.1  52.0  220   6  3   7.5   4.1 |  12.0  53.6  200  10  5   7.9   4.3
  9000  11.7  53.1  225   5  3   9.0   4.9 |  12.5  54.5  200   9  5   7.9   4.3
  8750  12.4  54.3  230   5  3   9.5   5.2 |  13.1  55.6  200   9  4   8.4   4.6
  8500  13.0  55.4  230   5  2   9.9   5.4 |  13.7  56.7  195   8  4   8.3   4.5
  8250  13.8  56.8  235   5  2  10.9   6.0 |  14.3  57.7  200   7  4   8.4   4.6
  8000  14.6  58.3  235   5  2  10.2   5.6 |  15.0  59.0  200   6  3   8.4   4.6
  7750  15.3  59.5  240   5  2   9.5   5.2 |  15.6  60.1  205   6  3   8.0   4.4
  7500  16.0  60.8  240   5  2   9.9   5.4 |  16.2  61.2  205   5  3   9.3   5.1
  7250  16.8  62.2  240   5  2  10.2   5.6 |  16.9  62.4  210   5  3  11.0   6.0
  7000  17.5  63.5  240   5  2   9.7   5.3 |  17.7  63.9  210   5  3  10.3   5.6
  6750  18.2  64.8  245   5  2   9.5   5.2 |  18.4  65.1  210   5  3   9.5   5.2
  6500  19.0  66.2  245   5  2  10.5   5.8 |  19.2  66.6  210   5  2   9.8   5.4
  6250  19.8  67.6  245   5  2  11.4   6.2 |  19.9  67.8  210   5  2  10.1   5.5
  6000  20.6  69.1  245   5  2  10.0   5.5 |  20.7  69.3  210   5  2  10.0   5.5
  5750  21.4  70.5  250   5  2  11.6   6.4 |  21.4  70.5  215   5  2  10.0   5.5
  5500  22.4  72.3  250   5  3  14.8   8.1 |  22.1  71.8  215   5  2  10.0   5.5
  5250  23.4  74.1  250   5  3  13.2   7.2 |  22.8  73.0  215   5  2  10.0   5.5
  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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