Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 201449
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0849 MDT Monday, April 20, 2015

This forecast is for Monday, April 20, 2015:

If the trigger temperature of 57.9 F/14.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1189 ft/min (6.0 m/s)
   Maximum height of thermals.................. 15834 ft MSL (10991 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1115 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................. 10600 ft MSL (5758 ft AGL)
Thermal soaring outlook for Tuesday 04/21...... Good

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

Remarks...

Sunrise/Sunset.................... 06:30:37 / 19:55:16 MDT
Total possible sunshine........... 13 hr 24 min 40 sec (804 min 40 sec)
Altitude of sun at 13:13:06 MDT... 62.49 degrees

Upper air data from rawinsonde observation taken on 04/20/2015 at 0600 MDT

Freezing level.................. 9841 ft MSL (4998 ft AGL)
Convective condensation level... 10810 ft MSL (5967 ft AGL)
Lifted condensation level....... 12098 ft MSL (7255 ft AGL)
Lifted index.................... -2.9
K index......................... +26.7

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  -56.6 -69.9   290   28   14   5.5   3.0  108.3 226.9    51.1      M    M
 45000  -54.0 -65.2   280   30   15  -1.1  -0.6   87.8 190.0    42.2      M    M
 40000  -56.9 -70.4   285   30   16   1.0   0.5   59.9 139.8    27.0      M    M
 38000  -56.7 -70.1   300   40   21   5.8   3.2   50.2 122.3    21.3      M    M
 36000  -57.1 -70.8   305   40   21   0.9   0.5   41.0 105.8    15.6      M    M
 34000  -55.8 -68.4   305   41   21   2.4   1.3   34.5  94.1    11.4      M    M
 32000  -52.6 -62.7   300   43   22   7.7   4.2   30.7  87.3     9.0      M    M
 30000  -48.0 -54.4   300   39   20   7.0   3.8   29.0  84.2     8.0      M    M
 29000  -45.8 -50.4   300   38   20   7.0   3.8   27.9  82.3     7.3      M    M
 28000  -43.2 -45.8   300   37   19   8.9   4.9   27.5  81.5     7.0      M    M
 27000  -40.8 -41.4   295   37   19   8.0   4.4   26.8  80.3     6.6      M    M
 26000  -38.3 -36.9   295   36   18   8.7   4.8   26.3  79.3     6.2      M    M
 25000  -35.7 -32.3   295   35   18   8.7   4.7   25.9  78.6     6.0      M    M
 24000  -33.1 -27.6   305   33   17   9.7   5.3   25.5  77.9     5.7      M    M
 23000  -30.3 -22.5   310   32   17   8.9   4.9   25.3  77.6     5.7      M    M
 22000  -27.7 -17.9   315   31   16   8.8   4.8   25.0  77.0     5.5      M    M
 21000  -25.1 -13.2   315   31   16   8.5   4.6   24.5  76.1     5.1      M    M
 20000  -22.2  -8.0   310   32   16   4.9   2.7   23.7  74.7     4.5      M    M
 19500  -21.4  -6.5   310   32   16   5.1   2.8   22.9  73.2     3.8      M    M
 19000  -20.6  -5.1   310   31   16   5.2   2.8   22.1  71.8     3.1      M    M
 18500  -19.7  -3.5   310   31   16   7.3   4.0   21.6  70.8     2.6      M    M
 18000  -18.8  -1.8   310   31   16   6.6   3.6   21.0  69.8     2.1      M    M
 17500  -17.8  -0.0   310   30   16   6.4   3.5   20.4  68.8     1.6      M    M
 17000  -16.9   1.6   310   30   15   7.3   4.0   19.9  67.8     1.1      M    M
 16500  -15.7   3.7   310   29   15   7.6   4.2   19.5  67.1     0.8      M    M
 16000  -15.0   5.0   310   29   15   5.0   2.7   18.8  65.8     0.1      M    M
 15500  -13.9   7.0   305   24   13   6.9   3.8   18.3  65.0    -0.3    953  4.8
 15000  -13.0   8.6   305   20   10   6.3   3.4   17.8  64.0    -0.8    910  4.6
 14500  -11.9  10.6   300   16    8   8.6   4.7   17.4  63.3    -1.2    862  4.4
 14000  -10.6  12.9   290   13    7   8.4   4.6   17.1  62.9    -1.4    810  4.1
 13500   -9.4  15.1   295   13    6   8.1   4.4   16.9  62.4    -1.7    758  3.9
 13000   -8.3  17.1   300   12    6   8.4   4.6   16.6  61.9    -2.0    709  3.6
 12500   -6.9  19.6   310   12    6   9.4   5.2   16.5  61.7    -2.2    655  3.3
 12000   -5.6  21.9   315   12    6   8.5   4.7   16.4  61.5    -2.3    601  3.1
 11500   -4.4  24.1   325   12    6   8.6   4.7   16.2  61.1    -2.6    548  2.8
 11000   -3.1  26.4   330   13    7   8.6   4.7   16.0  60.8    -2.8    496  2.5
 10500   -1.9  28.6   320   15    8   8.4   4.6   15.8  60.5    -3.0    444  2.3
 10250   -1.2  29.8   315   16    8   9.6   5.3   15.7  60.3    -3.1    418  2.1
 10000   -0.5  31.1   310   16    8   9.7   5.3   15.8  60.4    -3.1    388  2.0
  9750    0.2  32.4   305   13    7   8.7   4.8   15.7  60.2    -3.2    360  1.8
  9500    0.8  33.4   305   12    6   9.0   4.9   15.6  60.1    -3.3    333  1.7
  9250    1.5  34.7   310   11    6   8.8   4.8   15.5  60.0    -3.4    306  1.6
  9000    2.1  35.8   310   10    5   6.6   3.6   15.4  59.7    -3.5    280  1.4
  8750    2.5  36.5   305    8    4   5.1   2.8   15.1  59.1    -3.8    261  1.3
  8500    2.9  37.2   295    5    2   5.5   3.0   14.7  58.5    -4.2    242  1.2
  8250    3.3  37.9   265    2    1   5.4   3.0   14.4  57.9    -4.5    222  1.1
  8000    3.7  38.7   195    3    1   5.4   3.0   14.1  57.3    -4.9    203  1.0
  7750    4.1  39.4   165    4    2   5.4   3.0   13.7  56.7    -5.2    184  0.9
  7500    4.5  40.1   150    6    3   5.4   3.0   13.4  56.1    -5.6    164  0.8
  7250    4.9  40.8   145    8    4   5.4   2.9   13.1  55.5    -5.9    145  0.7
  7000    5.1  41.2   140   10    5  -0.4  -0.2   12.6  54.6    -6.4    130  0.7
  6750    4.8  40.6   140   13    7  -3.8  -2.1   11.6  52.8    -7.5    132  0.7
  6500    4.7  40.5   145   16    8   3.1   1.7   10.8  51.4    -8.3    128  0.6
  6250    5.1  41.2   145   19   10   6.5   3.6   10.4  50.8    -8.7    108  0.5
  6000    5.6  42.1   145   22   11   5.6   3.1   10.1  50.3    -9.0     88  0.4
  5750    6.0  42.8   140   20   10   5.8   3.2    9.8  49.7    -9.3     68  0.3
  5500    6.4  43.5   135   17    9   6.0   3.3    9.5  49.2    -9.7     48  0.2
  5250    6.8  44.2   130   13    7   4.8   2.6    9.2  48.6   -10.0     28  0.1
  5000    7.0  44.6   115   10    5   0.9   0.5    8.7  47.7   -10.6     15  0.1

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

           04/20/2015 at 0900 MDT          |       04/20/2015 at 1200 MDT
                                           |
K index... +21.3  LI... +272.8             | K index... +18.1  LI... +271.7
CAPE... +71.1  CIN... -21.4                | CAPE... +313.8  CIN... -14.8
                                           |
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 -57.3 -71.1  280  26 13   2.1   1.1 | -57.1 -70.8  285  26 13   1.7   0.9
 45000 -54.2 -65.6  285  31 16   2.3   1.3 | -54.6 -66.3  290  30 16   1.9   1.0
 40000 -56.7 -70.1  300  36 19  -1.8  -1.0 | -56.7 -70.1  305  31 16  -1.5  -0.8
 38000 -56.9 -70.4  300  38 19   1.6   0.9 | -56.9 -70.4  310  32 16   1.5   0.8
 36000 -56.0 -68.8  305  38 19   1.5   0.8 | -56.0 -68.8  310  33 17   1.5   0.8
 34000 -55.0 -67.0  305  37 19   4.1   2.3 | -55.0 -67.0  315  33 17   4.7   2.6
 32000 -51.8 -61.2  310  38 20   5.3   2.9 | -51.6 -60.9  315  36 18   5.7   3.1
 30000 -48.5 -55.3  310  39 20   7.8   4.3 | -48.0 -54.4  315  37 19   7.5   4.1
 29000 -46.1 -51.0  310  38 20   8.1   4.5 | -45.8 -50.4  315  37 19   7.6   4.2
 28000 -43.7 -46.7  310  38 20   8.1   4.5 | -42.9 -45.2  310  37 19   7.6   4.2
 27000 -40.6 -41.1  310  38 20   8.3   4.5 | -40.6 -41.1  310  37 19   8.0   4.4
 26000 -38.1 -36.6  310  37 19   8.5   4.7 | -38.1 -36.6  310  36 19   8.5   4.6
 25000 -35.6 -32.1  310  35 18   8.5   4.7 | -35.6 -32.1  310  36 18   8.5   4.6
 24000 -33.0 -27.4  310  34 17   8.5   4.7 | -33.0 -27.4  310  35 18   8.4   4.6
 23000 -30.4 -22.7  315  32 17   8.7   4.8 | -30.5 -22.9  310  33 17   8.3   4.6
 22000 -27.8 -18.0  315  31 16   8.7   4.8 | -28.0 -18.4  310  31 16   8.3   4.6
 21000 -25.2 -13.4  315  29 15   8.0   4.4 | -25.5 -13.9  310  30 15   8.3   4.6
 20000 -23.0  -9.4  315  27 14   7.5   4.1 | -23.0  -9.4  315  28 14   8.3   4.6
 19500 -21.8  -7.2  315  27 14   7.5   4.1 | -21.8  -7.2  315  27 14   8.3   4.6
 19000 -20.7  -5.3  315  26 13   7.5   4.1 | -20.6  -5.1  315  26 13   8.3   4.5
 18500 -19.6  -3.3  315  25 13   7.0   3.8 | -19.3  -2.7  315  25 13   7.9   4.3
 18000 -18.7  -1.7  315  24 13   6.3   3.4 | -18.2  -0.8  315  25 13   7.5   4.1
 17500 -17.7   0.1  310  24 12   6.3   3.4 | -17.1   1.2  315  24 12   7.5   4.1
 17000 -16.8   1.8  310  23 12   6.5   3.6 | -16.1   3.0  315  24 12   6.5   3.6
 16500 -15.8   3.6  310  22 11   6.5   3.5 | -15.1   4.8  315  23 12   6.6   3.6
 16000 -14.9   5.2  310  21 11   7.0   3.8 | -14.1   6.6  315  22 12   7.0   3.8
 15500 -13.8   7.2  310  20 10   7.2   3.9 | -13.1   8.4  310  21 11   7.1   3.9
 15000 -12.8   9.0  310  18  9   7.4   4.0 | -12.1  10.2  310  20 10   7.3   4.0
 14500 -11.7  10.9  310  17  9   7.6   4.2 | -11.0  12.2  310  19 10   7.6   4.1
 14000 -10.6  12.9  310  15  8   7.7   4.2 |  -9.9  14.2  305  18  9   7.6   4.2
 13500  -9.5  14.9  310  13  7   8.0   4.4 |  -8.2  17.2  300  17  9   7.7   4.2
 13000  -7.7  18.1  315  11  6   8.4   4.6 |  -7.0  19.4  295  16  8   8.4   4.6
 12500  -6.5  20.3  315  10  5   8.5   4.7 |  -5.8  21.6  295  15  7   8.6   4.7
 12000  -5.2  22.6  320   9  5   8.5   4.7 |  -4.6  23.7  290  13  7   8.3   4.6
 11500  -4.0  24.8  330   8  4   8.4   4.6 |  -3.4  25.9  285  11  6   8.2   4.5
 11000  -2.8  27.0  335   7  4   7.2   3.9 |  -2.2  28.0  285  10  5   7.4   4.0
 10500  -1.9  28.6  345   6  3   5.9   3.3 |  -1.2  29.8  280   8  4   6.4   3.5
 10250  -1.4  29.5  345   6  3   8.8   4.8 |  -0.7  30.7  280   7  3   9.3   5.1
 10000  -0.7  30.7  350   5  3  10.0   5.5 |   0.1  32.2  275   6  3   9.8   5.4
  9750  -0.0  32.0  355   5  3   8.1   4.4 |   0.7  33.3  270   5  3   7.3   4.0
  9500   0.6  33.1  360   5  2   8.5   4.6 |   1.2  34.2  265   4  2   7.9   4.4
  9250   1.2  34.2  005   4  2   8.9   4.9 |   1.8  35.2  260   4  2   7.8   4.3
  9000   1.8  35.2  015   4  2   5.0   2.7 |   2.4  36.3  245   3  2   7.8   4.3
  8750   1.9  35.4  030   3  1   1.7   0.9 |   2.9  37.2  235   3  2   7.6   4.2
  8500   2.0  35.6  060   2  1   2.1   1.2 |   3.5  38.3  225   3  2   7.7   4.2
  8250   2.2  36.0  085   3  1   3.7   2.0 |   4.0  39.2  210   3  2   7.6   4.2
  8000   2.5  36.5  105   3  2   6.0   3.3 |   4.6  40.3  200   3  2   7.2   4.0
  7750   3.0  37.4  115   4  2   5.9   3.2 |   5.1  41.2  195   3  2   6.8   3.8
  7500   3.4  38.1  125   5  2   6.0   3.3 |   5.5  41.9  185   3  2   7.4   4.1
  7250   3.8  38.8  125   5  3   6.5   3.6 |   6.1  43.0  185   3  2   9.4   5.1
  7000   4.3  39.7  130   5  3   6.2   3.4 |   6.8  44.2  185   4  2  10.3   5.6
  6750   4.8  40.6  135   5  3   4.6   2.5 |   7.6  45.7  185   4  2   9.8   5.4
  6500   5.1  41.2  145   6  3   4.0   2.2 |   8.3  46.9  185   4  2  10.5   5.8
  6250   5.4  41.7  145   6  3   4.1   2.3 |   9.1  48.4  185   4  2  11.3   6.2
  6000   5.7  42.3  150   5  3   4.5   2.5 |  10.0  50.0  185   4  2  10.6   5.8
  5750   6.1  43.0  155   5  3   7.4   4.1 |  10.8  51.4  185   3  2  11.2   6.1
  5500   6.7  44.1  150   5  3   9.8   5.4 |  11.7  53.1  185   3  2  13.9   7.6
  5250   7.4  45.3  145   5  3   9.0   4.9 |  12.7  54.9  185   3  2  15.5   8.5
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/20/2015 at 1500 MDT          |       04/20/2015 at 1800 MDT
                                           |
K index... +12.7  LI... +271.2             | K index... +15.7  LI... +271.9
CAPE... +312.0  CIN... -14.5               | CAPE... +117.6  CIN... -46.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.6 -71.7  280  27 14   1.3   0.7 | -57.8 -72.0  280  27 14   1.1   0.6
 45000 -55.6 -68.1  290  32 17   1.5   0.8 | -56.2 -69.2  290  33 17   1.3   0.7
 40000 -57.2 -71.0  300  27 14  -1.2  -0.6 | -57.9 -72.2  300  29 15  -1.2  -0.7
 38000 -57.2 -71.0  305  27 14   1.6   0.9 | -57.9 -72.2  305  28 15   1.5   0.8
 36000 -56.3 -69.3  310  29 15   1.6   0.9 | -57.0 -70.6  315  31 16   1.5   0.8
 34000 -55.1 -67.2  320  31 16   5.8   3.2 | -55.7 -68.3  320  33 17   7.0   3.8
 32000 -51.2 -60.2  320  32 17   6.4   3.5 | -51.5 -60.7  320  32 17   7.1   3.9
 30000 -47.3 -53.1  320  33 17   7.9   4.3 | -47.2 -53.0  325  31 16   8.3   4.5
 29000 -45.0 -49.0  320  33 17   7.8   4.3 | -44.7 -48.5  320  31 16   8.2   4.5
 28000 -42.7 -44.9  315  33 17   7.8   4.3 | -42.3 -44.1  320  31 16   8.2   4.5
 27000 -39.7 -39.5  315  33 17   7.8   4.3 | -39.2 -38.6  320  31 16   8.4   4.6
 26000 -37.4 -35.3  310  33 17   7.7   4.2 | -36.7 -34.1  320  31 16   8.5   4.7
 25000 -35.1 -31.2  310  33 17   7.7   4.2 | -34.1 -29.4  320  31 16   8.5   4.7
 24000 -32.8 -27.0  305  33 17   7.9   4.4 | -31.6 -24.9  315  31 16   8.4   4.6
 23000 -30.3 -22.5  310  32 16   8.4   4.6 | -29.1 -20.4  315  30 15   8.1   4.4
 22000 -27.8 -18.0  310  30 16   8.4   4.6 | -26.7 -16.1  315  29 15   8.1   4.4
 21000 -25.3 -13.5  310  29 15   8.2   4.5 | -24.3 -11.7  315  29 15   7.4   4.0
 20000 -22.9  -9.2  310  27 14   8.2   4.5 | -22.2  -8.0  320  29 15   7.2   4.0
 19500 -21.6  -6.9  310  26 13   8.2   4.5 | -21.1  -6.0  320  29 15   7.2   4.0
 19000 -20.4  -4.7  310  25 13   8.2   4.5 | -20.1  -4.2  320  29 15   7.2   4.0
 18500 -19.2  -2.6  310  24 12   8.1   4.5 | -19.0  -2.2  320  29 15   7.6   4.2
 18000 -18.0  -0.4  305  23 12   8.1   4.4 | -17.8  -0.0  320  29 15   7.9   4.3
 17500 -16.8   1.8  305  23 12   8.1   4.4 | -16.7   1.9  320  28 15   7.9   4.3
 17000 -15.7   3.7  310  22 12   7.1   3.9 | -15.5   4.1  320  28 14   8.1   4.5
 16500 -14.6   5.7  310  22 12   7.2   3.9 | -14.3   6.3  320  27 14   8.1   4.4
 16000 -13.5   7.7  310  22 12   7.4   4.1 | -13.0   8.6  325  26 13   8.5   4.7
 15500 -12.4   9.7  315  23 12   7.5   4.1 | -11.8  10.8  325  25 13   8.6   4.7
 15000 -11.3  11.7  315  23 12   7.8   4.3 | -10.5  13.1  325  23 12   8.5   4.7
 14500 -10.1  13.8  315  23 12   8.1   4.4 |  -9.3  15.3  325  22 11   8.5   4.6
 14000  -8.9  16.0  315  22 11   8.2   4.5 |  -8.0  17.6  325  21 11   8.6   4.7
 13500  -7.7  18.1  315  21 11   8.4   4.6 |  -6.7  19.9  325  19 10   8.8   4.8
 13000  -5.8  21.6  315  19 10   8.4   4.6 |  -4.8  23.4  325  16  8   8.6   4.7
 12500  -4.6  23.7  315  18  9   8.4   4.6 |  -3.6  25.5  325  15  8   8.5   4.7
 12000  -3.4  25.9  315  17  8   8.5   4.7 |  -2.4  27.7  325  13  7   8.7   4.8
 11500  -2.1  28.2  310  15  8   8.6   4.7 |  -1.1  30.0  320  12  6   8.8   4.8
 11000  -0.9  30.4  310  14  7   7.9   4.3 |   0.2  32.4  315  10  5   7.9   4.4
 10500   0.2  32.4  305  12  6   6.9   3.8 |   1.3  34.3  310   8  4   6.9   3.8
 10250   0.8  33.4  305  11  6   9.9   5.5 |   1.8  35.2  310   8  4   9.6   5.3
 10000   1.6  34.9  305  10  5  10.3   5.6 |   2.7  36.9  305   7  4   9.9   5.5
  9750   2.2  36.0  305   9  5   7.5   4.1 |   3.2  37.8  305   6  3   7.4   4.1
  9500   2.8  37.0  305   8  4   8.2   4.5 |   3.8  38.8  300   6  3   8.2   4.5
  9250   3.3  37.9  305   7  4   8.0   4.4 |   4.4  39.9  295   5  3   7.6   4.2
  9000   3.9  39.0  305   6  3   8.1   4.4 |   5.0  41.0  285   4  2   7.7   4.2
  8750   4.5  40.1  305   5  3   8.3   4.5 |   5.5  41.9  275   4  2   8.1   4.4
  8500   5.1  41.2  310   5  2   7.9   4.3 |   6.1  43.0  265   3  2   8.0   4.4
  8250   5.6  42.1  310   4  2   9.4   5.1 |   6.7  44.1  255   3  2   8.1   4.5
  8000   6.3  43.3  310   4  2  10.2   5.6 |   7.3  45.1  250   3  2   8.2   4.5
  7750   7.0  44.6  315   4  2   9.1   5.0 |   7.9  46.2  245   3  2   8.2   4.5
  7500   7.7  45.9  315   3  2   9.3   5.1 |   8.5  47.3  240   3  1   8.1   4.5
  7250   8.4  47.1  315   3  2  10.4   5.7 |   9.1  48.4  235   3  1   9.6   5.2
  7000   9.2  48.6  310   3  2  10.7   5.9 |   9.8  49.6  235   3  1  10.5   5.7
  6750  10.0  50.0  310   3  1   9.6   5.3 |  10.6  51.1  230   3  1   9.6   5.3
  6500  10.7  51.3  310   3  1  10.2   5.6 |  11.3  52.3  230   3  2   9.9   5.4
  6250  11.5  52.7  310   3  1  11.3   6.2 |  12.1  53.8  230   3  2  10.5   5.7
  6000  12.3  54.1  310   3  1  10.9   6.0 |  12.8  55.0  225   3  2  10.5   5.7
  5750  13.1  55.6  305   2  1  10.7   5.9 |  13.6  56.5  225   3  2  10.0   5.5
  5500  14.0  57.2  305   2  1  13.7   7.5 |  14.3  57.7  225   3  2   9.8   5.4
  5250  15.1  59.2  310   2  1  17.9   9.8 |  15.0  59.0  230   3  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 00.001 sec
                   West Longitude: 108 deg 31 min 59.998 sec
                   Elevation: 4839 feet (1475 meters)

and may not be representative of other areas along the Western Slope of
Colorado.  Note that some elevations in numerical weather prediction models
differ from actual station elevations, which can lead to data which appear
to be below ground.  Erroneous data such as these should not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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