Soaring Guidance
Issued by NWS Grand Junction, CO

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761
UXUS97 KGJT 111243
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0543 MST Thursday, February 11, 2016

This forecast is for Thursday, February 11, 2016:

If the trigger temperature of 58.7 F/14.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 193 ft/min (1.0 m/s)
   Maximum height of thermals.................. 6098 ft MSL (1259 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 C
Time of trigger temperature.................... None
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................. 5534 ft MSL (695 ft AGL)
Thermal soaring outlook for Friday 02/12....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:10:44 / 17:45:05 MST
Total possible sunshine........... 10 hr 34 min 21 sec (634 min 21 sec)
Altitude of sun at 12:28:14 MST... 36.91 degrees

Upper air data from rawinsonde observation taken on 02/11/2016 at 0500 MST

Freezing level.................. 5354 ft MSL (515 ft AGL)
Additional freezing level....... 11212 ft MSL (6373 ft AGL)
Convective condensation level... 20052 ft MSL (15213 ft AGL)
Lifted condensation level....... 10794 ft MSL (5955 ft AGL)
Lifted index.................... +16.3
K index......................... -16.7

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  -59.5 -75.1   295   30   16   2.0   1.1  103.4 218.1    55.2      M    M
 45000  -59.2 -74.6   300   55   28  -7.8  -4.3   77.7 171.8    43.6      M    M
 40000  -64.2 -83.6   315   41   21 -26.5 -14.5   46.9 116.4    26.6      M    M
 38000  -62.9 -81.2   320   47   24   8.3   4.6   39.8 103.7    22.6      M    M
 36000  -59.0 -74.2   325   46   24   4.2   2.3   37.1  98.7    21.4      M    M
 34000  -53.8 -64.8   335   46   24   9.6   5.3   36.1  97.0    21.3      M    M
 32000  -47.9 -54.2   340   47   24   7.7   4.2   35.1  95.1    21.2      M    M
 30000  -42.9 -45.2   335   46   24   9.1   5.0   34.1  93.4    21.0      M    M
 29000  -40.1 -40.2   330   47   24   9.1   5.0   33.8  92.8    21.0      M    M
 28000  -37.4 -35.3   330   48   25   8.9   4.9   33.6  92.4    21.1      M    M
 27000  -35.0 -31.0   325   44   23   8.0   4.4   32.9  91.2    20.8      M    M
 26000  -32.4 -26.3   325   40   20   9.5   5.2   32.4  90.4    20.7      M    M
 25000  -29.6 -21.3   320   36   19   9.5   5.2   32.4  90.3    20.9      M    M
 24000  -26.8 -16.2   320   36   19   9.2   5.0   32.2  89.9    21.0      M    M
 23000  -24.1 -11.4   325   36   19   9.2   5.0   31.9  89.5    21.0      M    M
 22000  -21.3  -6.3   330   37   19   9.2   5.1   31.8  89.2    21.1      M    M
 21000  -18.7  -1.7   330   37   19   8.8   4.8   31.5  88.6    21.1      M    M
 20000  -16.0   3.2   335   38   20   8.8   4.8   31.2  88.1    21.1      M    M
 19500  -14.8   5.4   335   35   18   7.0   3.9   30.9  87.7    21.0      M    M
 19000  -13.9   7.0   335   31   16   6.3   3.5   30.3  86.5    20.6      M    M
 18500  -12.9   8.8   335   29   15   6.8   3.7   29.7  85.5    20.2      M    M
 18000  -11.9  10.6   335   28   14   5.2   2.9   29.1  84.4    19.8      M    M
 17500  -11.1  12.0   335   26   14   5.0   2.8   28.4  83.0    19.3      M    M
 17000  -10.3  13.5   340   24   13   0.5   0.3   26.8  80.3    18.1      M    M
 16500  -10.3  13.5   340   23   12   1.0   0.6   25.2  77.4    16.7      M    M
 16000   -9.5  14.9   340   22   11   8.6   4.7   24.5  76.1    16.1      M    M
 15500   -8.2  17.2   335   21   11   4.9   2.7   24.2  75.5    16.0      M    M
 15000   -7.7  18.1   335   21   11   6.2   3.4   23.2  73.7    15.2      M    M
 14500   -6.6  20.1   330   20   10   6.9   3.8   22.7  72.9    14.9      M    M
 14000   -5.6  21.9   330   20   10   7.0   3.8   22.3  72.1    14.6      M    M
 13500   -4.6  23.7   330   19   10   7.0   3.8   21.8  71.3    14.2      M    M
 13000   -3.5  25.7   330   18    9   7.0   3.8   21.3  70.4    13.9      M    M
 12500   -2.5  27.5   330   18    9   7.0   3.9   20.9  69.7    13.5      M    M
 12000   -1.5  29.3   330   17    9   7.0   3.8   20.5  68.9    13.2      M    M
 11500   -0.4  31.3   325   13    7   6.7   3.7   20.1  68.1    12.8      M    M
 11000    0.2  32.4   320    9    4   3.0   1.6   19.2  66.6    12.1      M    M
 10500    0.7  33.3   305    5    3   3.4   1.8   18.2  64.7    11.1      M    M
 10250    0.9  33.6   295    4    2   3.9   2.2   17.7  63.8    10.7      M    M
 10000    1.2  34.2   300    5    2   4.2   2.3   17.2  63.0    10.3      M    M
  9750    1.5  34.7   300    5    3   4.1   2.2   16.8  62.2     9.9      M    M
  9500    1.8  35.2   300    5    3   4.2   2.3   16.3  61.4     9.5      M    M
  9250    2.1  35.8   305    6    3   3.9   2.2   15.9  60.6     9.1      M    M
  9000    2.4  36.3   305    6    3   4.9   2.7   15.5  59.8     8.7      M    M
  8750    2.7  36.9   310    4    2   1.5   0.8   15.0  59.0     8.3      M    M
  8500    2.6  36.7   320    3    1  -2.8  -1.6   14.1  57.4     7.4      M    M
  8250    2.3  36.1   355    2    1  -4.4  -2.4   13.1  55.6     6.4      M    M
  8000    2.1  35.8   060    2    1   0.9   0.5   12.1  53.8     5.5      M    M
  7750    2.2  36.0   090    2    1  -1.3  -0.7   11.6  52.8     4.9      M    M
  7500    1.8  35.2   110    3    2  -5.5  -3.0   10.4  50.7     3.7      M    M
  7250    1.5  34.7   120    4    2  -4.8  -2.6    9.3  48.8     2.7      M    M
  7000    1.1  34.0   130    5    2  -0.8  -0.4    8.2  46.8     1.6      M    M
  6750    1.5  34.7   125    5    3   7.3   4.0    7.8  46.1     1.2      M    M
  6500    1.9  35.4   125    5    3   5.7   3.1    7.6  45.7     1.0      M    M
  6250    2.2  36.0   120    6    3   1.8   1.0    7.2  44.9     0.6      M    M
  6000    2.3  36.1   115    6    3   3.3   1.8    6.5  43.7    -0.1    192  1.0
  5750    2.4  36.3   120    7    4  -6.7  -3.7    5.9  42.6    -0.7    182  0.9
  5500    1.2  34.2   130    9    5 -19.2 -10.5    4.0  39.1    -2.6    210  1.1
  5250   -0.1  31.8   135   11    6 -17.5  -9.6    1.9  35.4    -4.7    243  1.2
  5000   -1.6  29.1   130    8    4 -25.9 -14.2   -0.4  31.3    -7.0    281  1.4

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

           02/11/2016 at 0800 MST          |       02/11/2016 at 1100 MST
                                           |
K index... -5.5  LI... +280.7              | K index... -1.6  LI... +280.3
CAPE... 0.0  CIN... -0.0                   | 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 -60.5 -76.9  300  42 22   1.6   0.9 | -61.0 -77.8  300  39 20   1.5   0.8
 45000 -58.5 -73.3  300  50 26  -5.1  -2.8 | -59.0 -74.2  300  43 22  -3.3  -1.8
 40000 -65.3 -85.5  320  42 22  -4.4  -2.4 | -65.4 -85.7  315  40 21  -3.7  -2.0
 38000 -63.1 -81.6  325  41 21   7.5   4.1 | -62.8 -81.0  325  38 19   7.2   3.9
 36000 -58.6 -73.5  325  41 21   7.5   4.1 | -58.5 -73.3  335  35 18   7.2   3.9
 34000 -53.8 -64.8  330  40 21   8.7   4.8 | -53.6 -64.5  335  33 17   9.4   5.2
 32000 -48.6 -55.5  330  38 20   8.7   4.8 | -47.9 -54.2  330  32 16   9.4   5.2
 30000 -42.7 -44.9  330  37 19   8.8   4.8 | -42.4 -44.3  325  31 16   8.8   4.8
 29000 -40.1 -40.2  325  37 19   8.8   4.8 | -39.8 -39.6  325  31 16   8.8   4.8
 28000 -37.4 -35.3  320  37 19   8.8   4.8 | -37.2 -35.0  320  30 15   8.8   4.8
 27000 -34.7 -30.5  320  37 19   9.1   5.0 | -34.5 -30.1  320  30 16   8.8   4.8
 26000 -32.0 -25.6  320  37 19   9.1   5.0 | -31.9 -25.4  320  31 16   8.8   4.8
 25000 -29.3 -20.7  320  36 19   9.1   5.0 | -29.3 -20.7  320  32 16   8.8   4.8
 24000 -26.7 -16.1  320  36 18   8.6   4.7 | -26.7 -16.1  320  32 16   8.3   4.6
 23000 -24.1 -11.4  320  34 18   8.6   4.7 | -24.2 -11.6  320  31 16   8.4   4.6
 22000 -21.5  -6.7  320  33 17   8.6   4.7 | -21.1  -6.0  320  30 15   8.6   4.7
 21000 -19.1  -2.4  320  32 16   7.5   4.1 | -18.8  -1.8  320  29 15   7.2   3.9
 20000 -16.9   1.6  320  30 16   7.4   4.1 | -16.7   1.9  320  28 14   7.2   4.0
 19500 -15.8   3.6  320  29 15   7.4   4.1 | -15.6   3.9  320  27 14   7.2   4.0
 19000 -14.7   5.5  320  29 15   7.2   4.0 | -14.5   5.9  320  27 14   7.0   3.8
 18500 -13.7   7.3  320  28 14   6.2   3.4 | -13.5   7.7  320  27 14   6.9   3.8
 18000 -12.3   9.9  320  27 14   6.4   3.5 | -12.5   9.5  325  27 14   6.9   3.8
 17500 -11.3  11.7  320  26 13   6.6   3.6 | -11.4  11.5  325  26 13   7.1   3.9
 17000 -10.4  13.3  320  25 13   6.6   3.6 | -10.4  13.3  325  26 13   7.1   3.9
 16500  -9.4  15.1  320  24 12   6.9   3.8 |  -9.3  15.3  325  25 13   7.3   4.0
 16000  -8.3  17.1  320  23 12   6.9   3.8 |  -8.2  17.2  325  24 13   7.4   4.0
 15500  -7.3  18.9  320  23 12   6.9   3.8 |  -7.1  19.2  325  24 12   7.2   3.9
 15000  -6.3  20.7  325  22 11   6.8   3.8 |  -6.0  21.2  325  23 12   7.1   3.9
 14500  -5.2  22.6  325  22 11   6.7   3.7 |  -5.0  23.0  325  22 11   6.9   3.8
 14000  -4.2  24.4  325  21 11   6.5   3.5 |  -4.0  24.8  330  21 11   6.5   3.6
 13500  -3.3  26.1  325  20 10   6.4   3.5 |  -3.0  26.6  330  20 10   6.5   3.6
 13000  -2.4  27.7  325  19 10   5.8   3.2 |  -2.1  28.2  330  18  9   5.6   3.1
 12500  -1.5  29.3  330  17  9   5.8   3.2 |  -1.2  29.8  325  17  9   5.7   3.1
 12000  -0.7  30.7  330  16  8   5.7   3.1 |  -0.4  31.3  325  15  8   5.2   2.8
 11500   0.2  32.4  330  14  7   5.7   3.1 |   0.4  32.7  325  14  7   5.2   2.9
 11000   1.0  33.8  330  13  7   5.2   2.8 |   1.1  34.0  320  13  6   4.4   2.4
 10500   1.7  35.1  325  12  6   5.1   2.8 |   1.8  35.2  315  12  6   4.3   2.4
 10250   2.0  35.6  325  11  6   2.8   1.6 |   2.1  35.8  315  11  6   2.7   1.5
 10000   2.2  36.0  325  11  6   1.6   0.9 |   2.2  36.0  310  11  6   1.7   0.9
  9750   2.3  36.1  320  10  5   2.5   1.3 |   2.3  36.1  310  10  5   2.2   1.2
  9500   2.5  36.5  315   8  4   1.9   1.0 |   2.5  36.5  305   9  5   1.8   1.0
  9250   2.5  36.5  310   7  4   0.5   0.3 |   2.6  36.7  300   8  4   1.0   0.5
  9000   2.5  36.5  305   6  3   0.2   0.1 |   2.6  36.7  295   7  4   0.8   0.4
  8750   2.5  36.5  295   5  2   1.1   0.6 |   2.7  36.9  285   6  3   1.7   0.9
  8500   2.6  36.7  270   3  2   1.9   1.0 |   2.8  37.0  275   5  3   2.1   1.2
  8250   2.8  37.0  250   3  2   2.4   1.3 |   2.9  37.2  270   4  2   2.0   1.1
  8000   2.9  37.2  230   3  1   2.3   1.3 |   3.1  37.6  260   4  2   2.0   1.1
  7750   3.1  37.6  210   3  2   3.0   1.6 |   3.2  37.8  255   3  2   2.4   1.3
  7500   3.3  37.9  195   4  2   2.8   1.5 |   3.3  37.9  240   3  2   2.4   1.3
  7250   3.5  38.3  185   4  2   2.0   1.1 |   3.5  38.3  225   3  2   1.9   1.1
  7000   3.6  38.5  180   5  2   2.4   1.3 |   3.7  38.7  210   3  2   2.5   1.4
  6750   3.8  38.8  175   5  3   1.8   1.0 |   3.9  39.0  200   4  2   0.6   0.3
  6500   3.9  39.0  165   5  3  -0.5  -0.3 |   3.8  38.8  185   3  2  -0.6  -0.3
  6250   3.8  38.8  150   5  3   0.1   0.1 |   3.8  38.8  165   3  2   1.2   0.7
  6000   3.8  38.8  140   6  3  -5.2  -2.8 |   3.8  38.8  150   4  2  -1.6  -0.9
  5750   2.8  37.0  135   6  3 -22.8 -12.5 |   3.5  38.3  145   3  2  -1.5  -0.8
  5500   0.4  32.7  115   5  3 -35.1 -19.3 |   3.6  38.5  125   3  1   6.1   3.3
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  5000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/11/2016 at 1400 MST          |       02/11/2016 at 1700 MST
                                           |
K index... +0.7  LI... +280.2              | K index... +4.8  LI... +278.9
CAPE... 0.0  CIN... -0.9                   | 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 -60.5 -76.9  300  40 21   1.4   0.8 | -60.8 -77.4  295  41 21   1.1   0.6
 45000 -58.8 -73.8  300  43 22  -3.8  -2.1 | -59.3 -74.7  295  45 23  -2.9  -1.6
 40000 -64.1 -83.4  310  42 22  -3.3  -1.8 | -65.1 -85.2  310  48 24  -3.3  -1.8
 38000 -62.1 -79.8  315  36 19   6.2   3.4 | -62.2 -80.0  315  45 23   7.6   4.2
 36000 -58.4 -73.1  315  28 15   6.2   3.4 | -57.6 -71.7  310  42 22   7.6   4.2
 34000 -53.8 -64.8  315  24 12   9.6   5.3 | -52.7 -62.9  310  38 20   8.7   4.8
 32000 -47.4 -53.3  310  26 13   9.6   5.3 | -47.5 -53.5  305  34 18   8.7   4.8
 30000 -41.9 -43.4  310  27 14   8.9   4.9 | -42.2 -44.0  305  32 16   8.8   4.8
 29000 -39.2 -38.6  310  27 14   8.9   4.9 | -39.6 -39.3  305  32 16   8.8   4.8
 28000 -36.5 -33.7  310  27 14   8.9   4.9 | -37.0 -34.6  305  31 16   8.8   4.8
 27000 -33.9 -29.0  310  28 14   8.5   4.7 | -34.4 -29.9  305  31 16   8.7   4.7
 26000 -31.4 -24.5  310  28 15   8.5   4.7 | -31.8 -25.2  305  30 16   8.7   4.7
 25000 -28.8 -19.8  315  29 15   8.5   4.7 | -29.2 -20.6  305  30 15   8.7   4.8
 24000 -26.3 -15.3  315  29 15   8.3   4.5 | -26.6 -15.9  305  29 15   8.1   4.4
 23000 -23.9 -11.0  315  28 15   8.3   4.5 | -24.2 -11.6  305  29 15   8.1   4.5
 22000 -21.4  -6.5  315  28 14   8.3   4.5 | -21.2  -6.2  310  28 15   8.3   4.5
 21000 -19.1  -2.4  315  27 14   7.4   4.1 | -19.0  -2.2  310  28 14   6.9   3.8
 20000 -16.9   1.6  315  26 14   7.4   4.1 | -16.9   1.6  310  28 14   7.0   3.8
 19500 -15.8   3.6  315  26 13   7.4   4.1 | -15.9   3.4  310  28 14   7.0   3.8
 19000 -14.7   5.5  315  26 13   7.4   4.1 | -14.9   5.2  310  28 14   7.4   4.1
 18500 -13.1   8.4  315  25 13   7.2   4.0 | -13.7   7.3  310  27 14   7.6   4.2
 18000 -12.0  10.4  315  25 13   7.2   4.0 | -12.6   9.3  310  27 14   7.6   4.2
 17500 -11.0  12.2  320  24 13   7.1   3.9 | -11.5  11.3  310  26 13   6.9   3.8
 17000  -9.9  14.2  320  24 12   7.1   3.9 | -10.5  13.1  310  25 13   6.9   3.8
 16500  -8.8  16.2  320  23 12   7.3   4.0 |  -9.5  14.9  315  25 13   7.2   4.0
 16000  -7.8  18.0  320  23 12   7.3   4.0 |  -8.4  16.9  315  24 12   7.3   4.0
 15500  -6.7  19.9  320  22 11   7.1   3.9 |  -7.3  18.9  315  23 12   7.3   4.0
 15000  -5.6  21.9  320  21 11   7.0   3.8 |  -6.2  20.8  315  22 11   7.4   4.1
 14500  -4.6  23.7  320  20 10   6.9   3.8 |  -5.1  22.8  315  21 11   7.3   4.0
 14000  -3.6  25.5  320  19 10   6.6   3.6 |  -4.0  24.8  315  20 11   6.8   3.7
 13500  -2.6  27.3  320  18  9   6.5   3.6 |  -3.0  26.6  320  19 10   6.8   3.7
 13000  -1.7  28.9  320  17  9   5.9   3.2 |  -2.0  28.4  320  19 10   6.4   3.5
 12500  -0.8  30.6  315  16  8   5.9   3.2 |  -1.0  30.2  320  18  9   6.5   3.6
 12000   0.1  32.2  315  14  7   4.9   2.7 |  -0.1  31.8  315  17  9   5.7   3.1
 11500   0.8  33.4  310  13  7   5.0   2.8 |   0.8  33.4  315  16  8   5.9   3.2
 11000   1.5  34.7  305  12  6   3.8   2.1 |   1.5  34.7  315  15  8   3.3   1.8
 10500   2.1  35.8  305  11  6   3.8   2.1 |   2.0  35.6  315  14  7   3.6   2.0
 10250   2.3  36.1  300  11  6   2.0   1.1 |   2.3  36.1  310  13  7   2.3   1.3
 10000   2.4  36.3  300  11  5   1.5   0.8 |   2.4  36.3  310  13  6   1.6   0.9
  9750   2.5  36.5  295  10  5   2.3   1.3 |   2.5  36.5  310  11  6   2.2   1.2
  9500   2.7  36.9  290   9  5   2.1   1.1 |   2.7  36.9  305  10  5   2.2   1.2
  9250   2.8  37.0  285   8  4   1.8   1.0 |   2.9  37.2  300   9  5   2.5   1.4
  9000   2.9  37.2  280   8  4   1.8   1.0 |   3.0  37.4  300   8  4   2.6   1.4
  8750   3.1  37.6  275   7  4   2.8   1.5 |   3.2  37.8  295   7  4   3.0   1.7
  8500   3.3  37.9  270   6  3   2.6   1.4 |   3.5  38.3  295   6  3   2.8   1.5
  8250   3.4  38.1  260   5  3   1.8   1.0 |   3.6  38.5  290   5  2   2.2   1.2
  8000   3.6  38.5  255   5  2   1.9   1.1 |   3.8  38.8  285   4  2   2.1   1.2
  7750   3.7  38.7  245   4  2   1.6   0.9 |   3.9  39.0  275   3  2   2.7   1.5
  7500   3.8  38.8  235   4  2   1.6   0.9 |   4.1  39.4  255   2  1   2.1   1.1
  7250   3.9  39.0  225   3  2   1.9   1.0 |   4.2  39.6  240   2  1   1.2   0.7
  7000   4.0  39.2  215   3  2   1.8   1.0 |   4.3  39.7  215   2  1   1.3   0.7
  6750   4.1  39.4  205   3  2   1.8   1.0 |   4.4  39.9  195   2  1   1.9   1.0
  6500   4.2  39.6  205   3  1   2.3   1.2 |   4.5  40.1  180   2  1   2.2   1.2
  6250   4.3  39.7  205   2  1   1.7   0.9 |   4.5  40.1  165   1  1   1.3   0.7
  6000   4.4  39.9  205   1  1   5.0   2.8 |   4.5  40.1  140   1  1   3.1   1.7
  5750   4.9  40.8  200   1  1  11.0   6.0 |   4.7  40.5  135   1  1   4.5   2.5
  5500   5.7  42.3  205   1  1  11.3   6.2 |   4.9  40.8  120   1  0   2.6   1.4
  5250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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