Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201241
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0641 MDT Monday, October 20, 2014

This forecast is for Monday, October 20, 2014:

If the trigger temperature of 71.1 F/21.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 666 ft/min (3.4 m/s)
   Maximum height of thermals.................. 12735 ft MSL (7896 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7774 ft MSL (2935 ft AGL)
Thermal soaring outlook for Tuesday 10/21...... Excellent

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

Remarks...

Sunrise/Sunset.................... 07:29:01 / 18:29:44 MDT
Total possible sunshine........... 11 hr 0 min 44 sec (660 min 44 sec)
Altitude of sun at 12:58:58 MDT... 40.39 degrees

Upper air data from rawinsonde observation taken on 10/20/2014 at 0600 MDT

Freezing level.................. 12852 ft MSL (8013 ft AGL)
Convective condensation level... 13974 ft MSL (9135 ft AGL)
Lifted condensation level....... 13801 ft MSL (8961 ft AGL)
Lifted index.................... +1.6
K index......................... +23.2

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  -67.7 -89.9   250   17    9   8.0   4.4   83.2 181.7    34.2      M    M
 45000  -56.8 -70.2   285   22   11   6.6   3.6   75.5 168.0    32.1      M    M
 40000  -48.2 -54.8   325   19   10   7.9   4.3   66.4 151.4    28.1      M    M
 38000  -43.5 -46.3   300   20   10   6.3   3.5   64.6 148.3    27.7      M    M
 36000  -40.1 -40.2   315   19   10   5.8   3.2   61.1 142.0    26.0      M    M
 34000  -37.2 -35.0   285   17    9   3.8   2.1   57.0 134.5    23.7      M    M
 32000  -35.3 -31.5   255    7    4  -3.8  -2.1   50.4 122.8    19.5      M    M
 30000  -36.9 -34.4   180   12    6  -6.7  -3.7   40.4 104.7    12.4      M    M
 29000  -35.2 -31.4   170   13    7   9.4   5.1   38.9 102.0    11.4      M    M
 28000  -32.8 -27.0   210   12    6   7.7   4.2   38.2 100.7    11.0      M    M
 27000  -30.7 -23.3   215   12    6   9.2   5.1   37.1  98.8    10.3      M    M
 26000  -27.8 -18.0   225   12    6   9.8   5.4   37.1  98.7    10.4      M    M
 25000  -24.9 -12.8   230   12    6   8.2   4.5   37.0  98.6    10.5      M    M
 24000  -22.4  -8.3   205    8    4   8.5   4.7   36.5  97.7    10.1      M    M
 23000  -19.9  -3.8   200    8    4   6.2   3.4   36.1  96.9     9.9      M    M
 22000  -18.1  -0.6   195    9    5   8.5   4.6   34.7  94.5     8.8      M    M
 21000  -16.1   3.0   190    9    5   5.7   3.1   33.7  92.6     8.0      M    M
 20000  -14.4   6.1   185   10    5   5.7   3.1   32.3  90.1     6.8      M    M
 19500  -13.6   7.5   165    9    5   5.9   3.3   31.4  88.6     6.2      M    M
 19000  -12.9   8.8   145   10    5   6.7   3.7   30.7  87.3     5.6      M    M
 18500  -11.7  10.9   150    9    5   8.0   4.4   30.4  86.6     5.2      M    M
 18000  -10.0  14.0   170    9    5   8.0   4.4   29.9  85.8     4.9      M    M
 17500   -8.8  16.2   180    9    5   7.3   4.0   29.6  85.3     4.6      M    M
 17000   -8.1  17.4   190   11    5   4.0   2.2   28.8  83.9     3.9      M    M
 16500   -7.5  18.5   180   13    7   4.2   2.3   27.9  82.2     3.1      M    M
 16000   -6.9  19.6   175   15    8   4.2   2.3   27.0  80.5     2.2      M    M
 15500   -6.3  20.7   190   12    6   4.5   2.5   26.0  78.8     1.3      M    M
 15000   -5.3  22.5   210   11    6   8.9   4.9   25.6  78.1     0.9      M    M
 14500   -4.0  24.8   205   11    6   8.5   4.7   25.4  77.7     0.7      M    M
 14000   -2.8  27.0   200   11    6   8.5   4.7   25.2  77.4     0.5      M    M
 13500   -1.5  29.3   195   10    5   8.5   4.7   25.0  77.0     0.3      M    M
 13000   -0.3  31.5   190    9    4   8.5   4.7   24.8  76.6     0.1      M    M
 12500    1.0  33.8   180    8    4   8.6   4.7   24.6  76.3    -0.1    638  3.2
 12000    2.2  36.0   170    7    4   8.6   4.7   24.4  76.0    -0.3    586  3.0
 11500    3.5  38.3   170    6    3   8.5   4.7   24.2  75.6    -0.5    533  2.7
 11000    4.7  40.5   175    6    3   8.3   4.5   24.0  75.2    -0.8    481  2.4
 10500    6.1  43.0   180    5    3   8.0   4.4   23.7  74.7    -0.9    426  2.2
 10250    6.7  44.1   180    5    2   7.7   4.2   23.6  74.5    -1.0    400  2.0
 10000    7.2  45.0   175    3    2   7.4   4.0   23.4  74.1    -1.1    376  1.9
  9750    7.8  46.0   165    3    2   7.5   4.1   23.2  73.8    -1.3    353  1.8
  9500    8.3  46.9   160    4    2   7.4   4.1   23.0  73.5    -1.5    329  1.7
  9250    8.8  47.8   155    4    2   7.5   4.1   22.9  73.2    -1.7    306  1.6
  9000    9.4  48.9   150    5    3   7.5   4.1   22.7  72.9    -1.9    283  1.4
  8750    9.9  49.8   145    5    3   7.5   4.1   22.5  72.5    -2.1    259  1.3
  8500   10.4  50.7   135    6    3   7.5   4.1   22.3  72.2    -2.3    236  1.2
  8250   11.0  51.8   130    6    3   7.5   4.1   22.2  71.9    -2.5    212  1.1
  8000   11.5  52.7   125    7    4   7.6   4.2   22.0  71.6    -2.7    189  1.0
  7750   12.0  53.6   135    9    5   6.4   3.5   21.8  71.2    -3.0    166  0.8
  7500   12.4  54.3   140   11    6   3.0   1.6   21.4  70.5    -3.4    148  0.8
  7250   12.4  54.3   145   14    7  -3.0  -1.7   20.7  69.2    -4.1    141  0.7
  7000   12.1  53.8   150   16    8   0.7   0.4   19.7  67.5    -5.1    141  0.7
  6750   12.5  54.5   150   16    8   6.4   3.5   19.3  66.8    -5.4    122  0.6
  6500   12.9  55.2   145   14    7   4.9   2.7   19.0  66.2    -5.8    103  0.5
  6250   13.3  55.9   140   12    6   5.3   2.9   18.7  65.6    -6.1     84  0.4
  6000   13.7  56.7   135   10    5   5.3   2.9   18.3  65.0    -6.5     65  0.3
  5750   14.1  57.4   135    9    5   4.8   2.6   18.0  64.3    -6.8     46  0.2
  5500   14.5  58.1   135    8    4   6.6   3.6   17.6  63.7    -7.2     27  0.1
  5250   14.9  58.8   135    7    3  -0.1  -0.0   17.3  63.1    -7.6      7  0.0
  5000   13.9  57.0   130    6    3 -28.1 -15.4   15.6  60.1    -9.3     29  0.1

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

           10/20/2014 at 0900 MDT          |       10/20/2014 at 1200 MDT
                                           |
K index... +27.2  LI... -0.0               | K index... +28.3  LI... -0.1
CAPE... +20.8  CIN... -26.4                | CAPE... +28.1  CIN... -38.8
                                           |
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 -66.5 -87.7  280  15  8   5.4   3.0 | -66.0 -86.8  250  15  8   4.8   2.7
 45000 -58.0 -72.4  290  18  9   6.5   3.5 | -57.7 -71.9  265  20 10   6.5   3.6
 40000 -47.9 -54.2  290   8  4   6.0   3.3 | -48.0 -54.4  245  15  8   6.5   3.5
 38000 -44.2 -47.6  295   9  5   6.1   3.3 | -44.1 -47.4  260  13  7   6.5   3.5
 36000 -40.6 -41.1  295  11  5   6.1   3.4 | -40.2 -40.4  275  13  6   6.5   3.6
 34000 -38.7 -37.7  280   8  4   1.4   0.8 | -38.1 -36.6  265  10  5   1.9   1.0
 32000 -37.8 -36.0  225   6  3   1.4   0.8 | -36.9 -34.4  215   8  4   1.9   1.0
 30000 -35.9 -32.6  195   8  4   4.7   2.6 | -35.2 -31.4  190  11  6   3.8   2.1
 29000 -34.1 -29.4  190   9  5   4.8   2.6 | -33.8 -28.8  180  12  6   3.9   2.1
 28000 -32.7 -26.9  190  10  5   4.3   2.4 | -32.6 -26.7  175  14  7   3.4   1.8
 27000 -30.5 -22.9  185  10  5   8.7   4.8 | -30.5 -22.9  175  14  7   8.4   4.6
 26000 -27.9 -18.2  185  11  6   8.7   4.8 | -28.0 -18.4  180  15  8   8.4   4.6
 25000 -25.3 -13.5  185  11  6   8.7   4.8 | -25.5 -13.9  180  15  8   8.4   4.6
 24000 -22.8  -9.0  180  11  6   7.9   4.3 | -23.1  -9.6  185  16  8   8.0   4.4
 23000 -20.5  -4.9  175  11  6   7.9   4.3 | -20.8  -5.4  185  16  8   8.0   4.4
 22000 -18.2  -0.8  175  11  6   8.0   4.4 | -18.4  -1.1  190  16  8   8.1   4.4
 21000 -16.1   3.0  175  11  5   6.7   3.7 | -16.2   2.8  190  15  8   7.1   3.9
 20000 -14.1   6.6  180  10  5   6.7   3.7 | -14.1   6.6  195  14  7   7.1   3.9
 19500 -13.1   8.4  180  10  5   6.7   3.7 | -13.1   8.4  195  13  7   7.0   3.9
 19000 -12.2  10.0  185   9  5   6.4   3.5 | -12.1  10.2  195  13  6   6.4   3.5
 18500 -11.3  11.7  185   8  4   6.0   3.3 | -11.3  11.7  195  12  6   5.6   3.1
 18000 -10.4  13.3  185   7  4   6.1   3.3 | -10.4  13.3  195  11  6   5.6   3.1
 17500  -9.6  14.7  190   6  3   5.5   3.0 |  -9.6  14.7  195  10  5   5.5   3.0
 17000  -8.8  16.2  190   6  3   5.6   3.0 |  -8.8  16.2  195   9  5   5.6   3.1
 16500  -8.0  17.6  195   5  3   6.5   3.5 |  -8.0  17.6  195   9  4   6.4   3.5
 16000  -7.0  19.4  200   5  2   7.1   3.9 |  -7.0  19.4  195   7  4   7.0   3.8
 15500  -5.9  21.4  210   4  2   7.1   3.9 |  -6.0  21.2  195   6  3   7.0   3.8
 15000  -4.9  23.2  215   4  2   6.8   3.8 |  -5.0  23.0  200   6  3   6.5   3.6
 14500  -3.9  25.0  225   4  2   6.8   3.7 |  -4.1  24.6  210   6  3   6.5   3.6
 14000  -2.4  27.7  230   5  3   7.3   4.0 |  -2.6  27.3  220   6  3   7.0   3.8
 13500  -1.3  29.7  230   5  3   7.5   4.1 |  -1.6  29.1  225   7  3   7.3   4.0
 13000  -0.2  31.6  230   5  3   7.7   4.2 |  -0.5  31.1  230   7  3   7.9   4.3
 12500   0.9  33.6  230   5  3   7.9   4.3 |   0.6  33.1  230   7  3   8.0   4.4
 12000   2.1  35.8  235   5  3   8.6   4.7 |   1.8  35.2  235   7  4   8.5   4.7
 11500   3.3  37.9  235   6  3   8.6   4.7 |   3.1  37.6  235   8  4   8.5   4.7
 11000   4.6  40.3  235   6  3   8.4   4.6 |   4.4  39.9  235   8  4   8.3   4.6
 10500   5.9  42.6  235   6  3   5.2   2.9 |   5.6  42.1  235   8  4   4.7   2.6
 10250   6.1  43.0  230   6  3   5.0   2.8 |   5.9  42.6  235   8  4   6.0   3.3
 10000   6.8  44.2  225   6  3  10.2   5.6 |   6.7  44.1  235   8  4  12.0   6.6
  9750   7.5  45.5  220   6  3  10.3   5.7 |   7.5  45.5  235   8  4  11.0   6.0
  9500   8.3  46.9  220   6  3   9.0   4.9 |   8.3  46.9  235   8  4   9.6   5.3
  9250   8.8  47.8  215   6  3   6.5   3.6 |   8.9  48.0  235   8  4   7.0   3.8
  9000   9.3  48.7  205   6  3   6.9   3.8 |   9.4  48.9  230   8  4   7.9   4.4
  8750   9.9  49.8  200   7  3   8.0   4.4 |  10.0  50.0  225   8  4   9.2   5.1
  8500  10.4  50.7  195   7  4   6.7   3.7 |  10.7  51.3  225   8  4   7.7   4.2
  8250  10.9  51.6  185   8  4   5.6   3.1 |  11.2  52.2  220   8  4   6.3   3.5
  8000  11.3  52.3  180   9  5   5.2   2.9 |  11.6  52.9  210   8  4   6.2   3.4
  7750  11.6  52.9  175   9  5   4.5   2.5 |  12.1  53.8  205   7  4   5.7   3.1
  7500  11.9  53.4  170  10  5   3.5   1.9 |  12.5  54.5  200   7  3   6.0   3.3
  7250  12.1  53.8  170  10  5   2.4   1.3 |  12.9  55.2  195   6  3   5.9   3.3
  7000  12.3  54.1  165  10  5   3.3   1.8 |  13.3  55.9  190   6  3   6.4   3.5
  6750  12.5  54.5  160   9  5   0.7   0.4 |  13.9  57.0  190   5  3   8.6   4.7
  6500  12.4  54.3  155   8  4  -2.9  -1.6 |  14.6  58.3  190   5  2  10.5   5.7
  6250  12.1  53.8  145   8  4  -4.8  -2.6 |  15.4  59.7  190   5  2  10.8   5.9
  6000  11.9  53.4  135   7  4   0.2   0.1 |  16.2  61.2  190   4  2  10.0   5.5
  5750  12.0  53.6  120   7  3  -1.8  -1.0 |  16.9  62.4  190   4  2  10.7   5.9
  5500  11.5  52.7  110   6  3  -9.5  -5.2 |  17.8  64.0  195   4  2  12.2   6.7
  5250  10.9  51.6  100   5  2  -3.3  -1.8 |  18.7  65.7  195   4  2  11.0   6.0
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/20/2014 at 1500 MDT          |       10/20/2014 at 1800 MDT
                                           |
K index... +24.1  LI... -0.4               | K index... +24.3  LI... -1.0
CAPE... +34.5  CIN... -42.6                | CAPE... +47.1  CIN... -29.2
                                           |
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 -65.9 -86.6  240  20 10   5.0   2.7 | -66.2 -87.2  230  27 14   4.9   2.7
 45000 -57.6 -71.7  245  25 13   6.1   3.3 | -58.4 -73.1  235  30 16   6.1   3.3
 40000 -48.5 -55.3  240  22 11   6.8   3.7 | -48.9 -56.0  230  24 13   6.6   3.6
 38000 -44.5 -48.1  245  19 10   6.7   3.7 | -45.0 -49.0  235  22 11   6.5   3.6
 36000 -40.5 -40.9  250  15  8   6.7   3.7 | -41.1 -42.0  235  19 10   6.5   3.6
 34000 -38.1 -36.6  240  13  7   2.2   1.2 | -38.6 -37.5  230  17  9   2.7   1.5
 32000 -36.8 -34.2  210  14  7   2.2   1.2 | -37.0 -34.6  220  17  9   2.7   1.5
 30000 -34.9 -30.8  195  16  8   4.3   2.4 | -34.8 -30.6  210  19 10   4.6   2.5
 29000 -33.3 -27.9  190  18  9   4.4   2.4 | -33.4 -28.1  210  21 11   4.6   2.5
 28000 -32.0 -25.6  190  20 10   4.0   2.2 | -31.7 -25.1  205  24 12   4.3   2.3
 27000 -30.0 -22.0  190  20 10   7.8   4.3 | -29.6 -21.3  205  24 12   7.9   4.3
 26000 -27.6 -17.7  195  19 10   7.8   4.3 | -27.3 -17.1  205  23 12   7.9   4.3
 25000 -25.3 -13.5  200  19 10   7.8   4.3 | -24.9 -12.8  210  22 12   7.9   4.3
 24000 -23.0  -9.4  205  18  9   7.8   4.3 | -22.7  -8.9  210  21 11   7.4   4.1
 23000 -20.7  -5.3  205  18  9   7.8   4.3 | -20.5  -4.9  210  20 10   7.4   4.1
 22000 -18.3  -0.9  205  17  9   7.9   4.3 | -18.3  -0.9  210  19 10   7.5   4.1
 21000 -16.2   2.8  205  17  9   6.8   3.8 | -16.3   2.7  215  17  9   6.4   3.5
 20000 -14.2   6.4  205  16  8   6.8   3.7 | -14.4   6.1  220  16  8   6.4   3.5
 19500 -13.2   8.2  205  16  8   6.8   3.7 | -13.4   7.9  220  15  8   6.4   3.5
 19000 -12.2  10.0  205  16  8   6.4   3.5 | -12.5   9.5  225  15  7   6.4   3.5
 18500 -11.3  11.7  200  16  8   5.8   3.2 | -11.6  11.1  225  15  8   6.4   3.5
 18000 -10.5  13.1  200  16  8   5.6   3.1 | -10.6  12.9  230  15  8   6.2   3.4
 17500  -9.6  14.7  195  16  8   7.1   3.9 |  -9.6  14.7  230  15  8   7.8   4.3
 17000  -8.5  16.7  195  15  8   7.1   3.9 |  -8.5  16.7  225  15  8   7.7   4.2
 16500  -7.5  18.5  190  15  8   7.2   3.9 |  -7.3  18.9  225  15  8   7.5   4.1
 16000  -6.5  20.3  190  14  7   7.3   4.0 |  -6.3  20.7  220  15  8   7.3   4.0
 15500  -5.4  22.3  190  14  7   7.2   4.0 |  -5.2  22.6  215  16  8   7.3   4.0
 15000  -4.4  24.1  190  13  7   7.0   3.8 |  -4.2  24.4  210  16  8   7.3   4.0
 14500  -3.3  26.1  190  13  7   7.0   3.8 |  -3.1  26.4  210  15  8   7.4   4.1
 14000  -1.8  28.8  195  12  6   7.3   4.0 |  -2.1  28.2  210  14  7   7.3   4.0
 13500  -0.7  30.7  195  11  6   7.4   4.0 |  -0.6  30.9  210  12  6   7.4   4.1
 13000   0.4  32.7  200  10  5   7.5   4.1 |   0.5  32.9  210  10  5   7.8   4.3
 12500   1.5  34.7  200   9  5   7.5   4.1 |   1.7  35.1  205   9  5   7.8   4.3
 12000   2.6  36.7  205   8  4   7.5   4.1 |   2.8  37.0  205   8  4   7.6   4.2
 11500   3.7  38.7  205   7  4   7.6   4.1 |   3.9  39.0  200   7  3   7.6   4.2
 11000   4.8  40.6  210   6  3   7.9   4.4 |   5.1  41.2  200   6  3   8.4   4.6
 10500   6.0  42.8  215   5  3   5.2   2.8 |   6.4  43.5  195   5  2   5.0   2.7
 10250   6.3  43.3  220   5  2   6.4   3.5 |   6.6  43.9  195   4  2   5.8   3.2
 10000   7.0  44.6  225   4  2  11.0   6.0 |   7.3  45.1  195   4  2  10.9   6.0
  9750   7.7  45.9  230   4  2  10.1   5.5 |   8.1  46.6  195   3  2   9.7   5.3
  9500   8.4  47.1  235   4  2   9.3   5.1 |   8.8  47.8  195   3  1   9.3   5.1
  9250   9.0  48.2  240   3  2   7.0   3.8 |   9.4  48.9  195   2  1   7.4   4.1
  9000   9.5  49.1  250   3  2   7.7   4.2 |  10.0  50.0  190   2  1   7.9   4.3
  8750  10.1  50.2  260   3  2   8.8   4.8 |  10.6  51.1  185   1  1   8.9   4.9
  8500  10.8  51.4  270   3  1   8.1   4.5 |  11.3  52.3  170   1  0   8.2   4.5
  8250  11.3  52.3  280   3  1   7.5   4.1 |  11.9  53.4  000   0  0   7.7   4.2
  8000  11.9  53.4  290   3  1   8.0   4.4 |  12.4  54.3  000   0  0   7.1   3.9
  7750  12.5  54.5  295   3  1   8.4   4.6 |  12.9  55.2  000   0  0   6.6   3.6
  7500  13.1  55.6  295   3  2   9.2   5.0 |  13.4  56.1  310   1  0   6.9   3.8
  7250  13.8  56.8  295   3  2  10.0   5.5 |  13.9  57.0  300   1  1   7.1   3.9
  7000  14.6  58.3  295   3  2   9.8   5.4 |  14.4  57.9  295   1  1   7.1   3.9
  6750  15.3  59.5  295   3  2  10.1   5.5 |  14.9  58.8  285   2  1   7.8   4.3
  6500  16.1  61.0  295   3  2  10.4   5.7 |  15.5  59.9  280   2  1   9.2   5.0
  6250  16.8  62.2  295   3  2  10.9   6.0 |  16.3  61.3  275   2  1   9.9   5.4
  6000  17.6  63.7  295   3  2   9.8   5.4 |  17.0  62.6  275   2  1   9.6   5.3
  5750  18.3  64.9  295   3  2  10.5   5.8 |  17.6  63.7  270   2  1   6.6   3.6
  5500  19.2  66.6  295   3  2  12.4   6.8 |  17.9  64.2  270   2  1   3.9   2.1
  5250  20.1  68.2  295   3  2  10.9   6.0 |  18.2  64.8  275   2  1   5.6   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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