Soaring Guidance
Issued by NWS Grand Junction, CO

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000
UXUS97 KGJT 191238
SRGGJT

Soaring Forecast
National Weather Service Grand Junction, Colorado
0538 MST Friday, December 19, 2014

This forecast is for Friday, December 19, 2014:

If the trigger temperature of 40.6 F/4.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6788 ft MSL (1949 ft AGL)

Forecast maximum temperature................... 38.0 F/3.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 0600 AM MST
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Saturday 12/20..... Poor

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

Remarks...

Sunrise/Sunset.................... 07:28:38 / 16:54:07 MST
Total possible sunshine........... 9 hr 25 min 28 sec (565 min 28 sec)
Altitude of sun at 12:11:23 MST... 27.53 degrees

Upper air data from rawinsonde observation taken on 12/19/2014 at 0500 MST

Freezing level.................. 5494 ft MSL (655 ft AGL)
Convective condensation level... 8973 ft MSL (4134 ft AGL)
Lifted condensation level....... 8390 ft MSL (3551 ft AGL)
Lifted index.................... +11.7
K index......................... -4.7

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  -57.2 -71.0   285   39   20   2.7   1.5  109.6 229.4    60.0      M    M
 45000  -55.3 -67.5   280   38   19   0.9   0.5   87.9 190.2    51.0      M    M
 40000  -55.9 -68.6   290   47   24 -12.2  -6.7   62.3 144.1    38.2      M    M
 38000  -61.4 -78.5   300   37   19  -1.8  -1.0   45.1 113.1    27.8      M    M
 36000  -61.1 -78.0   330   44   23   3.9   2.1   36.8  98.2    22.9      M    M
 34000  -58.4 -73.1   335   66   34   8.4   4.6   32.3  90.1    20.4      M    M
 32000  -53.8 -64.8   335   60   31   7.8   4.3   30.6  87.1    19.7      M    M
 30000  -48.0 -54.4   340   52   27   8.7   4.8   29.6  85.2    19.5      M    M
 29000  -45.4 -49.7   340   48   25   8.7   4.8   29.1  84.4    19.4      M    M
 28000  -42.8 -45.0   340   44   23   8.7   4.8   28.7  83.7    19.4      M    M
 27000  -40.4 -40.7   340   41   21   7.6   4.2   28.0  82.4    19.0      M    M
 26000  -38.3 -36.9   340   37   19   7.6   4.2   27.1  80.7    18.6      M    M
 25000  -35.8 -32.4   340   34   18   8.3   4.5   26.5  79.7    18.3      M    M
 24000  -33.4 -28.1   335   36   19   8.0   4.4   25.9  78.7    18.1      M    M
 23000  -30.7 -23.3   330   38   20   9.0   4.9   25.5  77.8    17.9      M    M
 22000  -28.0 -18.4   325   40   20   9.0   4.9   25.2  77.3    17.9      M    M
 21000  -25.3 -13.5   320   42   22   9.2   5.0   25.0  77.0    18.0      M    M
 20000  -22.6  -8.7   330   38   20   9.2   5.1   24.8  76.7    18.1      M    M
 19500  -21.2  -6.2   330   36   19   9.2   5.1   24.7  76.5    18.1      M    M
 19000  -19.8  -3.6   325   34   18   8.8   4.8   24.6  76.3    18.1      M    M
 18500  -18.6  -1.5   325   33   17   8.5   4.6   24.4  75.9    18.0      M    M
 18000  -17.3   0.9   325   31   16   8.2   4.5   24.1  75.4    17.9      M    M
 17500  -16.3   2.7   330   30   15   2.1   1.1   23.6  74.5    17.6      M    M
 17000  -16.4   2.5   330   28   15   0.2   0.1   21.8  71.3    16.1      M    M
 16500  -17.0   1.4   320   26   14 -10.7  -5.9   19.5  67.1    14.1      M    M
 16000  -17.3   0.9   300   25   13   7.8   4.3   16.8  62.2    11.8      M    M
 15500  -16.4   2.5   300   19   10   2.4   1.3   16.1  60.9    11.2      M    M
 15000  -16.6   2.1   295   14    7  -3.4  -1.9   14.2  57.5     9.6      M    M
 14500  -17.1   1.2   290   16    8  -0.7  -0.4   12.0  53.6     7.8      M    M
 14000  -16.9   1.6   290   17    9   2.4   1.3   10.7  51.3     6.6      M    M
 13500  -16.4   2.5   290   15    8   2.8   1.5    9.6  49.3     5.5      M    M
 13000  -15.9   3.4   290   14    7   6.2   3.4    8.7  47.7     4.7      M    M
 12500  -14.9   5.2   290   12    6   7.2   3.9    8.2  46.8     4.2      M    M
 12000  -13.8   7.2   290   11    6   7.4   4.0    7.9  46.1     3.9      M    M
 11500  -12.7   9.1   285    9    5   7.4   4.1    7.5  45.4     3.6      M    M
 11000  -11.6  11.1   285    8    4   8.5   4.7    7.1  44.8     3.2      M    M
 10500  -10.6  12.9   275    6    3   4.5   2.5    6.7  44.1     2.8      M    M
 10250  -10.3  13.5   275    5    3   3.7   2.0    6.3  43.3     2.4      M    M
 10000  -10.0  14.0   270    5    3   5.3   2.9    5.8  42.5     2.0      M    M
  9750   -9.5  14.9   270    6    3   7.0   3.8    5.6  42.0     1.7      M    M
  9500   -8.9  16.0   275    7    3   8.5   4.6    5.4  41.7     1.6      M    M
  9250   -8.3  17.1   275    7    4   9.0   5.0    5.3  41.6     1.5      M    M
  9000   -7.6  18.3   275    8    4   8.9   4.9    5.3  41.5     1.4      M    M
  8750   -7.0  19.4   275    8    4   8.9   4.9    5.2  41.4     1.4      M    M
  8500   -6.3  20.7   275    7    4   8.9   4.9    5.2  41.3     1.3      M    M
  8250   -5.6  21.9   275    7    3   8.9   4.9    5.1  41.2     1.2      M    M
  8000   -5.0  23.0   275    6    3   8.9   4.9    5.0  41.1     1.2      M    M
  7750   -4.3  24.3   275    6    3   9.1   5.0    5.0  40.9     1.1      M    M
  7500   -3.7  25.3   275    6    3   8.4   4.6    4.9  40.8     1.0      M    M
  7250   -3.2  26.2   270    5    3   5.6   3.1    4.7  40.4     0.8      M    M
  7000   -2.9  26.8   270    5    3   4.7   2.6    4.3  39.7     0.4      M    M
  6750   -2.5  27.5   270    4    2   6.1   3.3    4.0  39.1     0.0      M    M
  6500   -2.0  28.4   270    3    1   6.5   3.5    3.7  38.7    -0.2     43  0.2
  6250   -1.5  29.3   270    2    1   6.4   3.5    3.5  38.2    -0.5     20  0.1
  6000   -1.0  30.2   000    0    0   6.3   3.4    3.2  37.8    -0.7      M    M
  5750   -0.5  31.1   000    0    0   6.9   3.8    3.0  37.3    -0.9      M    M
  5500   -0.1  31.8   160    1    0   4.4   2.4    2.7  36.9    -1.2      M    M
  5250    0.1  32.2   160    1    1   0.7   0.4    2.1  35.8    -1.7      M    M
  5000    0.2  32.4   160    2    1   3.0   1.6    1.5  34.7    -2.4      M    M

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

           12/19/2014 at 0800 MST          |       12/19/2014 at 1100 MST
                                           |
K index... -4.6  LI... +10.2               | K index... -8.4  LI... +10.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.0 -70.6  280  24 12   1.8   1.0 | -57.3 -71.1  270  24 13   1.3   0.7
 45000 -54.3 -65.7  285  22 11   1.6   0.9 | -55.4 -67.7  265  27 14   1.7   1.0
 40000 -60.5 -76.9  305  33 17  -4.5  -2.5 | -62.8 -81.0  290  36 19  -5.4  -3.0
 38000 -61.6 -78.9  315  38 20   3.1   1.7 | -64.0 -83.2  295  40 21   5.3   2.9
 36000 -59.8 -75.6  320  43 22   3.1   1.7 | -60.8 -77.4  295  41 21   5.4   3.0
 34000 -57.8 -72.0  325  48 24   7.0   3.8 | -57.5 -71.5  300  41 21   6.9   3.8
 32000 -52.8 -63.0  330  45 23   8.2   4.5 | -52.7 -62.9  300  39 20   8.0   4.4
 30000 -47.9 -54.2  335  44 22   8.5   4.7 | -47.4 -53.3  300  36 18   8.0   4.4
 29000 -45.3 -49.5  335  44 22   8.4   4.6 | -45.0 -49.0  305  36 18   8.0   4.4
 28000 -42.8 -45.0  335  44 23   8.4   4.6 | -42.6 -44.7  310  36 19   8.0   4.4
 27000 -40.3 -40.5  335  44 23   8.5   4.6 | -40.2 -40.4  315  36 19   8.2   4.5
 26000 -37.8 -36.0  335  42 22   8.2   4.5 | -37.5 -35.5  320  36 18   9.0   4.9
 25000 -35.3 -31.5  335  41 21   8.2   4.5 | -34.9 -30.8  325  35 18   9.0   4.9
 24000 -32.9 -27.2  335  39 20   8.2   4.5 | -32.2 -26.0  325  35 18   9.0   5.0
 23000 -30.4 -22.7  335  37 19   8.3   4.6 | -29.7 -21.5  330  33 17   8.0   4.4
 22000 -27.3 -17.1  330  34 18   8.3   4.6 | -27.3 -17.1  330  31 16   8.1   4.4
 21000 -24.8 -12.6  330  33 17   8.6   4.7 | -24.9 -12.8  330  28 14   8.1   4.4
 20000 -22.1  -7.8  330  32 16   8.7   4.8 | -22.5  -8.5  330  28 14   8.1   4.4
 19500 -20.8  -5.4  330  31 16   8.7   4.8 | -21.3  -6.3  330  28 14   8.1   4.4
 19000 -19.5  -3.1  330  31 16   8.7   4.8 | -20.1  -4.2  330  28 14   8.1   4.4
 18500 -18.2  -0.8  330  30 16   7.7   4.2 | -18.9  -2.0  330  28 14   8.1   4.4
 18000 -17.2   1.0  330  29 15   7.1   3.9 | -17.1   1.2  330  26 14   8.0   4.4
 17500 -16.1   3.0  335  28 14   7.0   3.8 | -15.9   3.4  330  26 13   7.8   4.3
 17000 -15.3   4.5  335  27 14   4.7   2.6 | -14.8   5.4  330  25 13   7.3   4.0
 16500 -14.5   5.9  330  26 13   5.2   2.8 | -13.7   7.3  330  24 12   7.8   4.3
 16000 -14.1   6.6  330  25 13   0.1   0.1 | -12.9   8.8  335  23 12   2.7   1.5
 15500 -14.1   6.6  330  25 13  -0.4  -0.2 | -12.4   9.7  335  23 12   3.2   1.8
 15000 -14.2   6.4  325  24 12  -0.4  -0.2 | -12.1  10.2  335  23 12   0.8   0.4
 14500 -14.3   6.3  325  23 12  -0.3  -0.2 | -12.1  10.2  335  22 11   0.2   0.1
 14000 -14.4   6.1  320  22 11   0.4   0.2 | -12.1  10.2  330  21 11   0.3   0.2
 13500 -14.2   6.4  315  20 10   1.5   0.8 | -12.0  10.4  330  19 10   0.5   0.3
 13000 -14.0   6.8  310  18 10   2.6   1.4 | -12.0  10.4  325  17  9   1.1   0.6
 12500 -13.4   7.9  305  17  9   4.8   2.7 | -11.7  10.9  320  15  8   1.9   1.0
 12000 -12.7   9.1  300  16  8   5.4   2.9 | -11.5  11.3  315  13  7   2.5   1.4
 11500 -11.8  10.8  300  15  8   6.5   3.5 | -11.0  12.2  305  11  6   3.4   1.8
 11000 -10.9  12.4  295  14  7   6.7   3.7 | -10.6  12.9  300  10  5   4.6   2.5
 10500  -9.9  14.2  295  13  6   7.0   3.8 |  -9.7  14.5  290   9  5   5.8   3.2
 10250  -9.4  15.1  295  12  6   7.0   3.9 |  -9.3  15.3  285   9  4   5.7   3.2
 10000  -8.9  16.0  290  12  6   4.0   2.2 |  -8.9  16.0  280   8  4   5.2   2.9
  9750  -8.7  16.3  290  11  6   4.4   2.4 |  -8.5  16.7  280   8  4   5.9   3.2
  9500  -8.2  17.2  290  11  5   7.2   3.9 |  -8.1  17.4  275   8  4   6.7   3.7
  9250  -7.8  18.0  290  10  5   6.1   3.3 |  -7.6  18.3  270   7  4   6.1   3.4
  9000  -7.4  18.7  285  10  5   5.1   2.8 |  -7.2  19.0  265   6  3   5.5   3.0
  8750  -7.0  19.4  285   9  5   5.4   3.0 |  -6.8  19.8  260   6  3   5.5   3.0
  8500  -6.6  20.1  280   9  5   6.1   3.4 |  -6.4  20.5  250   6  3   5.5   3.0
  8250  -6.1  21.0  275   9  4   5.9   3.3 |  -6.0  21.2  245   5  3   6.0   3.3
  8000  -5.7  21.7  270   8  4   5.8   3.2 |  -5.5  22.1  240   5  3   6.2   3.4
  7750  -5.2  22.6  270   8  4   6.3   3.4 |  -5.1  22.8  240   5  3   6.9   3.8
  7500  -4.8  23.4  260   7  4   6.2   3.4 |  -4.5  23.9  235   5  3   7.2   4.0
  7250  -4.4  24.1  250   6  3   5.3   2.9 |  -4.1  24.6  230   5  3   6.2   3.4
  7000  -4.0  24.8  235   5  3   4.9   2.7 |  -3.6  25.5  215   5  3   6.1   3.3
  6750  -3.6  25.5  215   5  3   5.5   3.0 |  -3.2  26.2  205   5  3   5.9   3.2
  6500  -3.2  26.2  200   5  3   5.3   2.9 |  -2.7  27.1  195   5  3   7.1   3.9
  6250  -2.8  27.0  190   5  3   4.6   2.5 |  -2.1  28.2  195   5  3   8.5   4.7
  6000  -2.4  27.7  180   5  3   5.1   2.8 |  -1.5  29.3  190   5  3   7.4   4.1
  5750  -2.1  28.2  175   6  3   2.7   1.5 |  -0.9  30.4  190   5  3  11.2   6.2
  5500  -2.1  28.2  175   5  2  -1.6  -0.9 |   0.2  32.4  190   5  3  19.5  10.7
  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

           12/19/2014 at 1400 MST          |       12/19/2014 at 1700 MST
                                           |
K index... -2.4  LI... +9.6                | K index... +3.6  LI... +7.2
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.2
                                           |
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 -57.7 -71.9  260  28 15   1.8   1.0 | -58.7 -73.7  265  31 16   1.3   0.7
 45000 -54.9 -66.8  270  36 19   2.2   1.2 | -56.7 -70.1  280  37 19   1.3   0.7
 40000 -60.8 -77.4  275  37 19  -4.4  -2.4 | -58.7 -73.7  280  39 20  -1.6  -0.9
 38000 -62.0 -79.6  275  38 20   3.1   1.7 | -59.4 -74.9  275  42 22  -0.1  -0.0
 36000 -60.1 -76.2  275  45 23   3.3   1.8 | -59.4 -74.9  270  51 26  -0.0  -0.0
 34000 -58.1 -72.6  275  51 26   5.6   3.1 | -59.4 -74.9  265  60 31   4.2   2.3
 32000 -52.8 -63.0  275  46 24   7.9   4.3 | -54.6 -66.3  265  53 27   8.0   4.4
 30000 -48.0 -54.4  280  41 21   8.3   4.5 | -49.8 -57.6  260  46 24   8.9   4.9
 29000 -45.5 -49.9  280  38 20   8.3   4.5 | -47.1 -52.8  260  43 22   9.0   4.9
 28000 -43.0 -45.4  285  36 18   8.3   4.5 | -44.4 -47.9  265  40 20   9.0   4.9
 27000 -40.6 -41.1  290  33 17   8.5   4.7 | -41.1 -42.0  265  36 18   9.1   5.0
 26000 -37.9 -36.2  290  32 16   9.2   5.0 | -38.3 -36.9  270  34 17   9.2   5.0
 25000 -35.1 -31.2  290  31 16   9.2   5.0 | -35.6 -32.1  275  33 17   9.2   5.0
 24000 -32.4 -26.3  290  30 16   9.2   5.1 | -32.8 -27.0  280  32 16   9.0   5.0
 23000 -29.9 -21.8  295  29 15   8.1   4.4 | -30.4 -22.7  285  32 16   8.1   4.4
 22000 -27.5 -17.5  295  27 14   8.1   4.4 | -28.0 -18.4  290  32 16   8.1   4.4
 21000 -25.1 -13.2  295  26 13   8.0   4.4 | -25.6 -14.1  295  32 16   7.4   4.0
 20000 -22.7  -8.9  300  25 13   7.8   4.3 | -23.5 -10.3  295  31 16   7.0   3.8
 19500 -21.6  -6.9  305  24 13   7.8   4.3 | -22.5  -8.5  295  30 16   7.0   3.8
 19000 -20.4  -4.7  305  24 12   7.8   4.3 | -21.5  -6.7  295  30 15   7.0   3.8
 18500 -18.6  -1.5  310  24 12   7.7   4.3 | -20.4  -4.7  295  30 15   7.1   3.9
 18000 -17.5   0.5  315  24 12   7.7   4.2 | -19.4  -2.9  295  28 14   7.2   3.9
 17500 -16.3   2.7  320  24 12   7.6   4.1 | -18.3  -0.9  300  25 13   7.1   3.9
 17000 -15.3   4.5  320  23 12   7.1   3.9 | -17.2   1.0  300  23 12   8.4   4.6
 16500 -14.2   6.4  325  22 12   7.2   4.0 | -15.9   3.4  305  22 11   8.3   4.5
 16000 -13.2   8.2  325  22 11   6.5   3.6 | -14.7   5.5  310  20 10   8.1   4.4
 15500 -12.2  10.0  330  21 11   6.7   3.7 | -13.5   7.7  315  19 10   8.0   4.4
 15000 -11.3  11.7  330  20 10   4.8   2.6 | -12.3   9.9  315  19 10   7.8   4.3
 14500 -10.7  12.7  330  19 10   4.3   2.4 | -11.2  11.8  315  18  9   7.3   4.0
 14000 -10.0  14.0  330  18  9   2.8   1.5 | -10.1  13.8  315  18  9   7.0   3.8
 13500  -9.8  14.4  325  17  9   1.6   0.9 |  -8.9  16.0  315  17  9   5.3   2.9
 13000  -9.6  14.7  320  16  8   0.7   0.4 |  -8.2  17.2  310  17  9   2.2   1.2
 12500  -9.7  14.5  315  15  8  -0.4  -0.2 |  -8.1  17.4  305  16  8   0.9   0.5
 12000  -9.8  14.4  305  14  7   0.3   0.1 |  -8.0  17.6  300  15  8  -0.5  -0.3
 11500  -9.6  14.7  295  12  6   1.4   0.8 |  -8.2  17.2  290  13  6  -1.3  -0.7
 11000  -9.4  15.1  285  10  5   3.0   1.6 |  -8.2  17.2  280  11  6   2.5   1.4
 10500  -8.8  16.2  275   9  5   4.8   2.7 |  -7.6  18.3  265  10  5   4.5   2.5
 10250  -8.4  16.9  270   9  5   4.5   2.5 |  -7.3  18.9  260  10  5   2.2   1.2
 10000  -8.1  17.4  265   9  4   3.4   1.9 |  -7.2  19.0  255  10  5   4.2   2.3
  9750  -7.8  18.0  260   9  4   6.2   3.4 |  -6.7  19.9  255  10  5   8.5   4.6
  9500  -7.2  19.0  260   9  4   8.9   4.9 |  -6.1  21.0  255  10  5   8.5   4.6
  9250  -6.7  19.9  260   9  4   7.4   4.0 |  -5.5  22.1  255  10  5   6.3   3.5
  9000  -6.2  20.8  260   8  4   5.2   2.9 |  -5.2  22.6  250  10  5   4.3   2.4
  8750  -5.8  21.6  260   8  4   6.1   3.3 |  -4.8  23.4  245   9  5   6.2   3.4
  8500  -5.3  22.5  255   7  4   7.9   4.3 |  -4.4  24.1  245   9  4   6.5   3.6
  8250  -4.8  23.4  255   7  3   6.5   3.5 |  -4.0  24.8  235   8  4   5.0   2.8
  8000  -4.4  24.1  245   6  3   5.8   3.2 |  -3.7  25.3  230   6  3   4.4   2.4
  7750  -3.9  25.0  235   5  2   5.2   2.8 |  -3.3  26.1  215   5  3   5.6   3.1
  7500  -3.6  25.5  220   4  2   4.8   2.6 |  -2.9  26.8  200   5  2   6.0   3.3
  7250  -3.2  26.2  205   4  2   6.3   3.4 |  -2.4  27.7  190   5  3   5.8   3.2
  7000  -2.7  27.1  195   4  2   6.5   3.6 |  -2.0  28.4  180   5  3   5.8   3.2
  6750  -2.2  28.0  185   4  2   6.8   3.8 |  -1.6  29.1  175   6  3   6.0   3.3
  6500  -1.7  28.9  180   4  2   9.2   5.1 |  -1.1  30.0  170   6  3   6.0   3.3
  6250  -0.9  30.4  180   4  2  10.7   5.9 |  -0.7  30.7  170   6  3   5.9   3.3
  6000  -0.2  31.6  180   4  2   9.9   5.4 |  -0.3  31.5  165   6  3   6.1   3.3
  5750   0.6  33.1  180   4  2  11.6   6.4 |   0.1  32.2  160   5  3   3.7   2.0
  5500   1.6  34.9  185   3  2  16.0   8.8 |   0.2  32.4  160   4  2   1.5   0.8
  5250     M     M    M   M  M     M     M |   0.4  32.7  155   4  2   3.2   1.8
  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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