Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 131215
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0515 MST Saturday, December 13, 2014

This forecast is for Saturday, December 13, 2014:

If the trigger temperature of 60.9 F/16.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8444 ft MSL (1686 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7502 ft MSL (744 ft AGL)
Thermal soaring outlook for Sunday 12/14....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:09:07 / 16:37:30 MST
Total possible sunshine........... 9 hr 28 min 23 sec (568 min 23 sec)
Altitude of sun at 11:53:22 MST... 27.94 degrees

Upper air data from numerical model forecast valid on 12/13/2014 at 0500 MST

Freezing level.................. 12877 ft MSL (6119 ft AGL)
Convective condensation level... 21990 ft MSL (15232 ft AGL)
Lifted condensation level....... 17383 ft MSL (10625 ft AGL)
Lifted index.................... +8.3
K index......................... +2.2

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  -65.7 -86.3   245   26   13   1.4   0.8      M     M       M      M    M
 45000  -63.5 -82.3   225   32   17   0.8   0.5      M     M       M      M    M
 40000  -62.2 -80.0   215   56   29   1.0   0.6      M     M       M      M    M
 38000  -59.0 -74.2   210   55   28   7.1   3.9      M     M       M      M    M
 36000  -54.8 -66.6   200   50   26   7.1   3.9      M     M       M      M    M
 34000  -50.1 -58.2   195   47   24   8.9   4.9      M     M       M      M    M
 32000  -44.1 -47.4   190   45   23   8.9   4.9      M     M       M      M    M
 30000  -39.0 -38.2   190   44   23   8.2   4.5   30.4  86.8    12.7      M    M
 29000  -36.5 -33.7   190   44   22   8.2   4.5   29.8  85.6    12.4      M    M
 28000  -34.1 -29.4   190   43   22   8.2   4.5   29.3  84.7    12.1      M    M
 27000  -31.6 -24.9   190   43   22   8.8   4.8   28.8  83.9    11.9      M    M
 26000  -29.0 -20.2   190   44   23   8.8   4.8   28.4  83.1    11.7      M    M
 25000  -26.3 -15.3   190   44   23   8.9   4.9   28.1  82.6    11.5      M    M
 24000  -23.8 -10.8   190   45   23   6.9   3.8   27.7  81.8    11.3      M    M
 23000  -21.8  -7.2   185   45   23   7.0   3.8   26.6  79.9    10.5      M    M
 22000  -19.7  -3.5   185   45   23   7.0   3.8   25.7  78.2     9.8      M    M
 21000  -17.6   0.3   185   45   23   6.7   3.7   24.7  76.5     9.0      M    M
 20000  -15.6   3.9   185   43   22   6.7   3.7   23.6  74.5     8.2      M    M
 19500  -14.6   5.7   185   42   21   6.7   3.7   23.1  73.6     7.8      M    M
 19000  -13.6   7.5   185   41   21   6.7   3.7   22.6  72.8     7.4      M    M
 18500  -12.6   9.3   185   39   20   6.7   3.7   22.2  71.9     7.0      M    M
 18000  -11.6  11.1   190   37   19   6.7   3.7   21.6  70.9     6.6      M    M
 17500  -10.6  12.9   190   36   18   7.0   3.9   21.1  70.0     6.1      M    M
 17000   -9.5  14.9   190   34   17   7.8   4.3   20.8  69.4     5.9      M    M
 16500   -8.3  17.1   190   32   16   7.9   4.3   20.4  68.8     5.6      M    M
 16000   -7.1  19.2   195   29   15   7.4   4.1   20.1  68.2     5.4      M    M
 15500   -5.4  22.3   195   25   13   7.4   4.1   19.5  67.2     4.9      M    M
 15000   -4.3  24.3   200   23   12   6.6   3.6   19.1  66.3     4.5      M    M
 14500   -3.3  26.1   200   20   10   6.6   3.6   18.6  65.4     4.1      M    M
 14000   -2.3  27.9   205   18    9   7.3   4.0   18.1  64.6     3.7      M    M
 13500   -1.2  29.8   210   15    8   7.3   4.0   17.7  63.9     3.3      M    M
 13000   -0.1  31.8   210   13    7   7.6   4.2   17.4  63.2     3.0      M    M
 12500    1.1  34.0   215   11    6   7.8   4.3   17.0  62.6     2.7      M    M
 12000    2.3  36.1   215   11    6   8.7   4.8   16.8  62.2     2.5      M    M
 11750    3.0  37.4   220   10    5   8.6   4.7   16.7  62.1     2.5      M    M
 11500    3.6  38.5   220   10    5   8.7   4.8   16.6  61.9     2.4      M    M
 11250    4.3  39.7   220   10    5   8.4   4.6   16.5  61.8     2.3      M    M
 11000    4.9  40.8   225    9    5   8.1   4.4   16.4  61.5     2.2      M    M
 10750    5.5  41.9   230    9    5   8.0   4.4   16.3  61.3     2.1      M    M
 10500    6.1  43.0   235   10    5   8.3   4.5   16.1  61.1     1.9      M    M
 10250    6.7  44.1   240   10    5   7.3   4.0   16.0  60.8     1.8      M    M
 10000    7.2  45.0   245   10    5   6.3   3.4   15.8  60.4     1.6      M    M
  9750    7.6  45.7   250   10    5   7.0   3.9   15.5  59.9     1.3      M    M
  9500    8.2  46.8   255   10    5   7.5   4.1   15.3  59.6     1.1      M    M
  9250    8.7  47.7   260   10    5   7.0   3.9   15.2  59.3     0.9      M    M
  9000    9.2  48.6   260   11    6   6.2   3.4   14.9  58.9     0.7      M    M
  8750    9.6  49.3   260   12    6   5.3   2.9   14.6  58.3     0.4      M    M
  8500   10.0  50.0   260   12    6   6.5   3.5   14.3  57.7     0.1      M    M
  8250   10.4  50.7   265   13    7   2.1   1.1   14.0  57.1    -0.3     95  0.5
  8000   10.2  50.4   265   13    7  -6.6  -3.6   13.0  55.4    -1.2     94  0.5
  7750    9.7  49.5   265   13    7  -3.0  -1.6   11.8  53.3    -2.5    101  0.5
  7500    9.9  49.8   265   12    6   8.1   4.4   11.3  52.3    -3.0     89  0.4
  7250    9.9  49.8   265   11    6 -20.3 -11.1   10.6  51.1    -3.7     81  0.4
  7000    6.1  43.0   270    9    5 -76.3 -41.9    6.7  44.1    -7.6    188  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/13/2014 at 0800 MST          |       12/13/2014 at 1100 MST
                                           |
K index... -10.7  LI... +5.3               | K index... -4.3  LI... +4.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -64.7 -84.5  220  27 14   1.7   0.9 | -63.6 -82.5  215  34 18   1.4   0.8
 45000 -62.3 -80.1  205  33 17  -0.0  -0.0 | -61.6 -78.9  200  44 23   0.9   0.5
 40000 -62.0 -79.6  205  61 31   0.2   0.1 | -60.3 -76.5  205  65 33   0.8   0.4
 38000 -59.1 -74.4  205  63 32   7.2   3.9 | -57.9 -72.2  200  67 34   5.9   3.2
 36000 -54.7 -66.5  200  60 31   7.2   3.9 | -54.3 -65.7  195  67 34   5.9   3.2
 34000 -50.2 -58.4  195  57 30   8.3   4.6 | -50.5 -58.9  185  66 34   7.8   4.3
 32000 -44.6 -48.3  195  52 27   8.3   4.6 | -45.2 -49.4  185  60 31   7.8   4.3
 30000 -39.5 -39.1  190  49 25   8.6   4.7 | -40.3 -40.5  185  58 30   8.6   4.7
 29000 -36.9 -34.4  185  49 25   8.6   4.7 | -37.7 -35.9  180  58 30   8.6   4.7
 28000 -34.4 -29.9  185  48 25   8.6   4.7 | -35.2 -31.4  180  59 30   8.6   4.7
 27000 -31.9 -25.4  180  48 25   7.5   4.1 | -32.7 -26.9  180  59 31   8.0   4.4
 26000 -29.6 -21.3  185  49 25   7.6   4.2 | -30.2 -22.4  180  59 30   8.1   4.4
 25000 -27.3 -17.1  185  49 25   7.6   4.2 | -27.8 -18.0  180  58 30   8.1   4.4
 24000 -25.0 -13.0  185  49 25   8.1   4.4 | -25.4 -13.7  185  58 30   7.4   4.1
 23000 -22.6  -8.7  185  48 25   8.1   4.4 | -23.3  -9.9  185  54 28   7.2   3.9
 22000 -20.1  -4.2  185  47 24   8.1   4.4 | -21.1  -6.0  185  51 26   7.2   3.9
 21000 -17.8  -0.0  185  46 23   6.7   3.7 | -19.0  -2.2  185  47 24   6.7   3.7
 20000 -15.7   3.7  185  42 22   6.9   3.8 | -17.0   1.4  190  43 22   6.8   3.7
 19500 -14.7   5.5  185  40 21   6.9   3.8 | -16.0   3.2  190  41 21   6.8   3.7
 19000 -13.6   7.5  190  39 20   7.0   3.8 | -15.0   5.0  195  39 20   6.8   3.7
 18500 -12.6   9.3  190  37 19   5.8   3.2 | -14.0   6.8  200  37 19   6.5   3.6
 18000 -11.8  10.8  190  35 18   5.7   3.1 | -13.0   8.6  200  34 18   6.4   3.5
 17500 -11.0  12.2  190  32 17   5.9   3.2 | -12.0  10.4  200  32 17   6.3   3.5
 17000 -10.0  14.0  195  31 16   6.6   3.6 | -11.1  12.0  200  30 16   5.8   3.2
 16500  -9.0  15.8  195  29 15   6.6   3.6 | -10.2  13.6  205  28 14   5.9   3.2
 16000  -8.1  17.4  200  27 14   6.2   3.4 |  -9.4  15.1  205  26 13   6.0   3.3
 15500  -6.7  19.9  205  25 13   6.2   3.4 |  -8.0  17.6  210  23 12   5.9   3.2
 15000  -5.7  21.7  205  23 12   6.9   3.8 |  -7.1  19.2  210  20 10   6.9   3.8
 14500  -4.7  23.5  205  20 10   6.8   3.7 |  -6.1  21.0  210  18  9   6.8   3.7
 14000  -3.7  25.3  210  17  9   7.1   3.9 |  -5.0  23.0  210  16  8   7.7   4.2
 13500  -2.6  27.3  210  15  8   7.1   3.9 |  -3.8  25.2  205  15  8   7.9   4.3
 13000  -1.5  29.3  205  12  6   8.7   4.8 |  -2.6  27.3  205  13  7   8.1   4.4
 12500  -0.2  31.6  205  12  6   9.1   5.0 |  -1.4  29.5  200  11  6   8.3   4.6
 12000   1.2  34.2  210  10  5   8.6   4.7 |  -0.1  31.8  200  10  5   9.4   5.2
 11750   1.8  35.2  215  10  5   8.2   4.5 |   0.6  33.1  200   9  5   8.8   4.8
 11500   2.4  36.3  220   9  5   8.3   4.6 |   1.3  34.3  205   9  5   9.1   5.0
 11250   3.0  37.4  225   9  5   8.1   4.5 |   1.9  35.4  205   9  5   8.8   4.8
 11000   3.6  38.5  235  10  5   7.3   4.0 |   2.6  36.7  215   9  5   8.1   4.4
 10750   4.1  39.4  245  10  5   6.9   3.8 |   3.1  37.6  225   9  5   7.8   4.3
 10500   4.6  40.3  250  11  6   7.0   3.9 |   3.7  38.7  235  10  5   7.9   4.3
 10250   5.1  41.2  260  12  6   6.9   3.8 |   4.3  39.7  245  11  6   8.1   4.4
 10000   5.6  42.1  265  14  7   6.2   3.4 |   4.9  40.8  250  13  7   6.9   3.8
  9750   6.1  43.0  270  15  8   5.8   3.2 |   5.3  41.5  255  14  7   5.6   3.0
  9500   6.5  43.7  275  16  8   5.9   3.2 |   5.7  42.3  260  15  8   5.7   3.1
  9250   6.9  44.4  275  17  9   6.0   3.3 |   6.1  43.0  265  17  9   5.7   3.1
  9000   7.3  45.1  280  18  9   6.6   3.6 |   6.5  43.7  270  18  9   5.3   2.9
  8750   7.8  46.0  280  18 10   6.6   3.6 |   6.8  44.2  275  17  9   6.0   3.3
  8500   8.3  46.9  280  19 10   7.5   4.1 |   7.3  45.1  275  16  8   6.9   3.8
  8250   8.8  47.8  285  20 10   4.1   2.2 |   7.8  46.0  275  15  7   6.6   3.6
  8000   8.8  47.8  285  20 10  -2.2  -1.2 |   8.2  46.8  275  13  7   5.9   3.2
  7750   8.7  47.7  285  19 10   1.4   0.8 |   8.6  47.5  275  11  6   7.3   4.0
  7500   9.1  48.4  280  18  9   8.3   4.5 |   9.3  48.7  275   9  5   9.8   5.4
  7250   9.1  48.4  280  15  8 -18.2 -10.0 |  10.0  50.0  275   8  4   7.8   4.3
  7000   5.8  42.4  285  11  6 -64.0 -35.1 |  10.4  50.7  270   7  3   4.0   2.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/13/2014 at 1400 MST          |       12/13/2014 at 1700 MST
                                           |
K index... +5.4  LI... +1.6                | K index... +2.4  LI... +1.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.4 -80.3  220  35 18   1.5   0.8 | -61.0 -77.8  230  35 18   1.0   0.5
 45000 -60.0 -76.0  210  49 25   1.2   0.7 | -59.4 -74.9  215  48 25   2.3   1.2
 40000 -58.2 -72.8  200  57 29   1.2   0.6 | -55.5 -67.9  205  46 24   2.6   1.4
 38000 -56.7 -70.1  195  61 31   3.7   2.0 | -54.0 -65.2  200  49 25   2.4   1.3
 36000 -54.4 -65.9  190  66 34   3.7   2.0 | -52.6 -62.7  190  55 28   2.4   1.3
 34000 -51.6 -60.9  185  71 36   8.3   4.6 | -50.8 -59.4  185  62 32   6.3   3.5
 32000 -46.7 -52.1  180  67 34   8.3   4.5 | -47.3 -53.1  180  63 33   5.9   3.2
 30000 -41.0 -41.8  180  64 33   8.8   4.8 | -42.9 -45.2  175  65 33   8.6   4.7
 29000 -38.4 -37.1  180  64 33   8.8   4.8 | -40.3 -40.5  180  65 33   8.7   4.8
 28000 -35.7 -32.3  185  64 33   8.8   4.8 | -37.7 -35.9  180  64 33   8.7   4.8
 27000 -33.2 -27.8  185  64 33   7.3   4.0 | -35.1 -31.2  180  64 33   7.5   4.1
 26000 -31.1 -24.0  190  62 32   7.0   3.8 | -33.2 -27.8  185  59 30   6.5   3.6
 25000 -29.0 -20.2  190  61 31   7.0   3.8 | -31.2 -24.2  190  54 28   6.5   3.6
 24000 -26.9 -16.4  190  60 31   7.0   3.8 | -29.3 -20.7  200  50 26   6.8   3.7
 23000 -24.8 -12.6  195  56 29   7.0   3.8 | -27.0 -16.6  200  46 24   7.7   4.2
 22000 -22.7  -8.9  195  52 27   7.0   3.8 | -24.7 -12.5  200  42 22   7.7   4.2
 21000 -20.6  -5.1  195  48 25   6.8   3.7 | -22.4  -8.3  200  38 20   7.8   4.3
 20000 -18.6  -1.5  200  43 22   6.7   3.7 | -20.0  -4.0  205  35 18   7.9   4.3
 19500 -17.6   0.3  200  40 21   6.7   3.7 | -18.8  -1.8  205  34 18   7.9   4.3
 19000 -16.6   2.1  200  38 20   6.7   3.7 | -17.6   0.3  205  33 17   7.9   4.3
 18500 -15.6   3.9  200  36 18   6.6   3.6 | -16.4   2.5  210  31 16   7.6   4.2
 18000 -14.6   5.7  205  34 18   6.6   3.6 | -15.3   4.5  210  30 15   6.9   3.8
 17500 -13.6   7.5  205  33 17   6.6   3.6 | -14.3   6.3  210  28 14   7.0   3.8
 17000 -12.7   9.1  205  31 16   5.7   3.1 | -13.3   8.1  210  26 13   5.9   3.2
 16500 -11.9  10.6  210  28 15   5.8   3.2 | -12.5   9.5  215  23 12   5.9   3.2
 16000 -11.0  12.2  210  26 13   6.5   3.6 | -11.6  11.1  215  21 11   5.7   3.1
 15500 -10.0  14.0  210  23 12   6.8   3.7 | -10.8  12.6  215  18  9   5.6   3.1
 15000  -8.5  16.7  210  19 10   7.8   4.3 |  -9.5  14.9  210  15  8   7.1   3.9
 14500  -7.3  18.9  210  17  9   7.8   4.3 |  -8.5  16.7  210  13  7   7.4   4.1
 14000  -6.2  20.8  210  15  8   8.3   4.6 |  -7.4  18.7  205  11  6   8.1   4.4
 13500  -4.9  23.2  210  13  7   8.6   4.7 |  -6.1  21.0  210  10  5   8.6   4.7
 13000  -3.6  25.5  205  12  6   8.7   4.8 |  -4.9  23.2  215  10  5   8.9   4.9
 12500  -2.3  27.9  210  10  5   8.7   4.8 |  -3.5  25.7  215   9  5   9.2   5.1
 12000  -1.2  29.8  215  10  5   7.7   4.2 |  -2.4  27.7  220   8  4   7.7   4.2
 11750  -0.6  30.9  220  10  5   8.1   4.5 |  -1.8  28.8  220   8  4   8.9   4.9
 11500  -0.0  32.0  225  10  5   8.2   4.5 |  -1.1  30.0  220   7  4   8.8   4.8
 11250   0.6  33.1  235  10  5   7.7   4.2 |  -0.5  31.1  220   7  4   9.4   5.2
 11000   1.1  34.0  240  10  5   7.8   4.3 |   0.2  32.4  215   6  3   9.7   5.3
 10750   1.7  35.1  245   9  5   8.5   4.7 |   0.9  33.6  210   6  3   8.9   4.9
 10500   2.3  36.1  245   9  4   8.3   4.5 |   1.6  34.9  205   5  3   8.6   4.7
 10250   2.9  37.2  250   8  4   9.0   4.9 |   2.2  36.0  205   5  3   8.8   4.8
 10000   3.5  38.3  255   7  4   6.4   3.5 |   2.8  37.0  200   5  2   8.3   4.5
  9750   3.9  39.0  255   7  3   6.8   3.7 |   3.4  38.1  195   5  3   8.1   4.4
  9500   4.6  40.3  250   6  3   9.7   5.3 |   4.0  39.2  195   5  3   8.4   4.6
  9250   5.2  41.4  245   5  3   9.0   4.9 |   4.7  40.5  195   5  3   8.6   4.7
  9000   5.9  42.6  235   4  2   7.7   4.2 |   5.3  41.5  190   5  3   7.5   4.1
  8750   6.4  43.5  220   4  2   8.3   4.6 |   5.8  42.4  190   6  3   6.7   3.7
  8500   7.2  45.0  210   4  2  10.2   5.6 |   6.3  43.3  190   6  3   7.3   4.0
  8250   7.9  46.2  200   4  2   9.3   5.1 |   6.8  44.2  190   7  3   6.9   3.8
  8000   8.5  47.3  190   4  2   8.2   4.5 |   7.2  45.0  185   7  4   4.5   2.5
  7750   9.1  48.4  185   5  2   7.8   4.3 |   7.5  45.5  180   8  4   4.1   2.2
  7500   9.7  49.5  185   5  2   8.6   4.7 |   7.9  46.2  180   8  4   8.5   4.6
  7250  10.3  50.5  180   5  2   7.2   3.9 |   8.4  47.1  175   7  4   0.3   0.2
  7000  10.7  51.3  180   5  2   3.9   2.2 |   7.6  45.7  170   5  3 -20.9 -11.5
  6750     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 near the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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