Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 211117
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0517 MDT Saturday, May 21, 2016

This forecast is for Saturday, May 21, 2016:

If the trigger temperature of 66.7 F/19.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 1101 ft/min (5.6 m/s)
   Maximum height of thermals.................. 18233 ft MSL (11475 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 12369 ft MSL (5612 ft AGL)
Thermal soaring outlook for Sunday 05/22....... Good

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

Remarks...

Sunrise/Sunset.................... 05:41:20 / 20:09:48 MDT
Total possible sunshine........... 14 hr 28 min 28 sec (868 min 28 sec)
Altitude of sun at 12:55:45 MDT... 71.42 degrees

Upper air data from numerical model forecast valid on 05/21/2016 at 0600 MDT

Freezing level.................. 14059 ft MSL (7301 ft AGL)
Convective condensation level... 16205 ft MSL (9447 ft AGL)
Lifted condensation level....... 16612 ft MSL (9854 ft AGL)
Lifted index.................... -2.7
K index......................... +24.1

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  -63.8 -82.8   250   36   18  -0.7  -0.4      M     M       M      M    M
 45000  -64.5 -84.1   250   49   25   2.2   1.2      M     M       M      M    M
 40000  -61.3 -78.3   235   27   14   1.7   0.9      M     M       M      M    M
 38000  -57.3 -71.1   230   25   13   7.1   3.9      M     M       M      M    M
 36000  -53.1 -63.6   230   24   12   7.1   3.9      M     M       M      M    M
 34000  -48.4 -55.1   225   23   12   8.2   4.5      M     M       M      M    M
 32000  -43.5 -46.3   220   22   11   8.2   4.5      M     M       M      M    M
 30000  -38.6 -37.5   210   21   11   8.2   4.5   30.9  87.7     5.9      M    M
 29000  -36.2 -33.2   210   20   10   8.2   4.5   30.3  86.5     5.4      M    M
 28000  -33.1 -27.6   205   20   10   8.1   4.4   29.7  85.4     5.0      M    M
 27000  -30.5 -22.9   205   20   10   8.9   4.9   29.2  84.6     4.7      M    M
 26000  -27.9 -18.2   200   22   11   8.9   4.9   28.9  83.9     4.5      M    M
 25000  -25.2 -13.4   200   23   12   8.9   4.9   28.6  83.5     4.3      M    M
 24000  -22.6  -8.7   200   24   12   8.7   4.8   28.3  82.9     4.1      M    M
 23000  -20.0  -4.0   195   26   13   8.7   4.8   27.8  82.1     3.8      M    M
 22000  -17.4   0.7   195   28   14   8.7   4.8   27.5  81.5     3.5      M    M
 21000  -15.2   4.6   195   27   14   6.4   3.5   26.6  79.9     2.8      M    M
 20000  -13.3   8.1   195   25   13   6.4   3.5   25.4  77.8     1.8      M    M
 19500  -12.4   9.7   200   24   12   6.5   3.6   24.9  76.8     1.3      M    M
 19000  -11.5  11.3   200   22   12   6.6   3.6   24.4  75.9     0.8      M    M
 18500  -10.5  13.1   200   21   11   6.9   3.8   23.9  75.0     0.3      M    M
 18000   -9.5  14.9   200   19   10   7.0   3.8   23.4  74.1    -0.2   1086  5.5
 17500   -8.5  16.7   200   18    9   7.3   4.0   23.0  73.3    -0.6   1041  5.3
 17000   -7.5  18.5   205   19   10   7.4   4.1   22.6  72.6    -1.1    995  5.1
 16500   -6.4  20.5   205   19   10   7.7   4.2   22.2  71.9    -1.5    950  4.8
 16000   -5.3  22.5   200   18    9   8.0   4.4   21.9  71.4    -1.9    901  4.6
 15500   -4.2  24.4   195   17    9   8.0   4.4   21.6  70.9    -2.2    853  4.3
 15000   -2.9  26.8   195   16    8   9.3   5.1   21.4  70.6    -2.4    800  4.1
 14500   -1.6  29.1   195   15    8   9.2   5.0   21.3  70.4    -2.5    745  3.8
 14000    0.5  32.9   205   14    7   9.3   5.1   21.2  70.2    -2.7    661  3.4
 13500    1.9  35.4   210   15    8   9.3   5.1   21.1  70.0    -2.8    604  3.1
 13000    3.2  37.8   220   15    8   9.0   4.9   21.0  69.9    -2.9    549  2.8
 12500    4.6  40.3   225   17    9   8.6   4.7   20.9  69.7    -3.0    493  2.5
 12000    5.8  42.4   240   18    9   8.1   4.4   20.7  69.2    -3.3    443  2.3
 11750    6.4  43.5   240   18   10   8.1   4.4   20.5  68.9    -3.4    418  2.1
 11500    7.0  44.6   245   19   10   8.1   4.4   20.4  68.7    -3.6    393  2.0
 11250    7.6  45.7   250   20   10   8.1   4.4   20.3  68.5    -3.7    368  1.9
 11000    8.2  46.8   250   19   10   8.5   4.7   20.1  68.3    -3.8    342  1.7
 10750    8.8  47.8   255   19   10   8.8   4.8   20.1  68.1    -3.9    315  1.6
 10500    9.5  49.1   255   19   10   9.2   5.0   20.0  68.0    -4.0    288  1.5
 10250   10.1  50.2   260   19   10   7.3   4.0   19.9  67.9    -4.1    262  1.3
 10000   10.6  51.1   260   20   10   7.9   4.3   19.7  67.5    -4.3    239  1.2
  9750   11.3  52.3   260   20   10  10.1   5.5   19.7  67.4    -4.4    210  1.1
  9500   12.0  53.6   260   20   10   9.6   5.3   19.7  67.4    -4.4    181  0.9
  9250   12.8  55.0   260   20   10   9.2   5.1   19.7  67.4    -4.4    153  0.8
  9000   13.4  56.1   260   20   11   8.8   4.8   19.6  67.3    -4.5    125  0.6
  8750   14.1  57.4   260   21   11   9.4   5.2   19.6  67.2    -4.5     97  0.5
  8500   14.8  58.6   260   21   11  10.4   5.7   19.6  67.2    -4.5     68  0.3
  8250   15.4  59.7   260   21   11   2.5   1.4   19.4  67.0    -4.7     43  0.2
  8000   15.2  59.4   260   19   10  -6.3  -3.4   18.4  65.2    -5.7     43  0.2
  7750   14.9  58.8   255   18    9   2.9   1.6   17.5  63.4    -6.7     44  0.2
  7500   15.3  59.5   255   15    8   1.2   0.6   17.1  62.9    -7.0     24  0.1
  7250   14.5  58.1   255   12    6 -24.5 -13.4   15.8  60.4    -8.4     41  0.2
  7000   11.8  53.2   260    9    5 -41.6 -22.8   12.9  55.3   -11.3    115  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           05/21/2016 at 0900 MDT          |       05/21/2016 at 1200 MDT
                                           |
K index... +17.6  LI... +272.0             | K index... -18.0  LI... +274.7
CAPE... +43.1  CIN... -70.2                | CAPE... 0.0  CIN... -1.8
                                           |
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 -63.3 -81.9  260  35 18  -1.6  -0.9 | -63.3 -81.9  260  38 19  -1.2  -0.7
 45000 -65.0 -85.0  255  48 25   2.5   1.4 | -64.7 -84.5  255  51 26   1.9   1.1
 40000 -61.2 -78.2  250  34 18   2.2   1.2 | -61.7 -79.1  260  47 24   1.7   0.9
 38000 -57.0 -70.6  245  31 16   7.5   4.1 | -57.3 -71.1  255  40 21   8.1   4.4
 36000 -52.5 -62.5  240  28 14   7.5   4.1 | -52.4 -62.3  250  33 17   8.1   4.4
 34000 -47.9 -54.2  235  26 13   7.8   4.3 | -47.5 -53.5  245  30 16   8.4   4.6
 32000 -43.2 -45.8  230  24 13   7.8   4.3 | -42.4 -44.3  245  31 16   8.4   4.6
 30000 -38.4 -37.1  225  24 12   8.4   4.6 | -36.7 -34.1  240  30 15   8.6   4.7
 29000 -35.2 -31.4  220  24 12   8.4   4.6 | -34.1 -29.4  240  29 15   8.6   4.7
 28000 -32.7 -26.9  215  24 12   8.4   4.6 | -31.5 -24.7  240  29 15   8.6   4.7
 27000 -30.1 -22.2  215  25 13   8.5   4.7 | -29.1 -20.4  230  29 15   7.8   4.3
 26000 -27.6 -17.7  210  26 13   8.5   4.7 | -26.8 -16.2  225  29 15   7.8   4.3
 25000 -25.0 -13.0  205  27 14   8.5   4.7 | -24.4 -11.9  220  29 15   7.8   4.3
 24000 -22.6  -8.7  205  28 14   7.9   4.3 | -22.3  -8.1  215  30 15   6.0   3.3
 23000 -20.2  -4.4  205  28 15   7.9   4.3 | -20.5  -4.9  215  31 16   6.0   3.3
 22000 -17.9  -0.2  205  29 15   7.9   4.3 | -18.7  -1.7  215  33 17   6.0   3.3
 21000 -16.0   3.2  205  29 15   5.3   2.9 | -16.6   2.1  210  33 17   8.2   4.5
 20000 -14.4   6.1  200  30 16   5.4   2.9 | -14.1   6.6  210  32 17   8.2   4.5
 19500 -13.7   7.3  200  31 16   5.5   3.0 | -12.8   9.0  210  32 16   8.2   4.5
 19000 -12.9   8.8  200  31 16   6.0   3.3 | -11.6  11.1  210  31 16   8.1   4.4
 18500 -11.9  10.6  200  31 16   7.1   3.9 | -10.4  13.3  210  30 16   7.7   4.2
 18000 -10.9  12.4  200  30 15   7.2   3.9 |  -9.3  15.3  210  29 15   7.6   4.2
 17500  -9.8  14.4  195  29 15   9.2   5.0 |  -8.1  17.4  215  28 14   8.2   4.5
 17000  -8.4  16.9  195  29 15   9.3   5.1 |  -6.9  19.6  215  28 14   8.2   4.5
 16500  -7.1  19.2  190  28 14   9.3   5.1 |  -5.6  21.9  220  27 14   7.5   4.1
 16000  -5.7  21.7  190  27 14   9.3   5.1 |  -4.7  23.5  220  30 15   6.4   3.5
 15500  -4.3  24.3  190  26 13   9.3   5.1 |  -3.7  25.3  225  32 17   6.5   3.6
 15000  -2.9  26.8  195  25 13   9.0   4.9 |  -2.3  27.9  225  34 18   7.2   3.9
 14500  -0.8  30.6  195  24 12   8.9   4.9 |  -1.3  29.7  225  35 18   7.8   4.3
 14000   0.5  32.9  200  24 12   8.7   4.7 |  -0.0  32.0  225  33 17   8.8   4.8
 13500   1.8  35.2  205  24 12   8.7   4.8 |   1.2  34.2  220  31 16   8.8   4.8
 13000   3.1  37.6  210  24 13   8.8   4.8 |   2.6  36.7  220  29 15   9.5   5.2
 12500   4.4  39.9  215  25 13   7.1   3.9 |   4.0  39.2  215  28 14   7.9   4.3
 12000   5.5  41.9  220  25 13   8.8   4.8 |   5.2  41.4  215  25 13   9.7   5.3
 11750   6.1  43.0  225  25 13   8.3   4.5 |   5.9  42.6  210  25 13   9.1   5.0
 11500   6.7  44.1  225  24 12   8.3   4.6 |   6.5  43.7  210  24 12   9.5   5.2
 11250   7.3  45.1  230  24 12   8.6   4.7 |   7.2  45.0  210  23 12   8.4   4.6
 11000   7.9  46.2  230  22 11   8.5   4.7 |   7.8  46.0  210  23 12   8.8   4.8
 10750   8.5  47.3  235  20 10   8.0   4.4 |   8.5  47.3  205  22 11  10.0   5.5
 10500   9.0  48.2  240  19 10   8.3   4.6 |   9.3  48.7  205  22 11  10.3   5.6
 10250   9.6  49.3  245  17  9   7.6   4.2 |  10.0  50.0  200  21 11   7.9   4.3
 10000  10.2  50.4  245  16  8   8.2   4.5 |  10.4  50.7  200  20 10   8.3   4.6
  9750  10.8  51.4  245  14  7   9.2   5.1 |  11.2  52.2  200  20 10  11.1   6.1
  9500  11.5  52.7  250  13  7   9.0   4.9 |  12.0  53.6  200  20 10  10.5   5.7
  9250  12.1  53.8  255  11  6   8.7   4.8 |  12.8  55.0  195  20 10  10.0   5.5
  9000  12.7  54.9  255  10  5   8.3   4.6 |  13.5  56.3  195  19 10   9.6   5.3
  8750  13.3  55.9  255  10  5   8.9   4.9 |  14.2  57.6  195  19 10  10.4   5.7
  8500  14.0  57.2  260   9  4   8.8   4.8 |  15.0  59.0  195  19 10  10.7   5.9
  8250  14.6  58.3  265   8  4   7.4   4.1 |  15.8  60.4  195  19 10  10.5   5.8
  8000  15.0  59.0  260   7  3   5.7   3.1 |  16.6  61.9  190  19 10  10.9   6.0
  7750  15.5  59.9  260   6  3   8.8   4.8 |  17.4  63.3  190  18  9   9.4   5.2
  7500  16.2  61.2  255   5  3  10.2   5.6 |  18.0  64.4  190  18  9   9.5   5.2
  7250  16.8  62.2  250   4  2   6.6   3.6 |  18.8  65.8  190  17  9  13.1   7.2
  7000  17.2  63.0  245   4  2   6.4   3.5 |  19.8  67.6  190  16  8  14.2   7.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/21/2016 at 1500 MDT          |       05/21/2016 at 1800 MDT
                                           |
K index... +11.1  LI... +273.1             | K index... +2.4  LI... +275.1
CAPE... +18.2  CIN... -34.6                | 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 -61.2 -78.2  250  41 21  -1.7  -0.9 | -61.8 -79.2  260  31 16  -1.0  -0.5
 45000 -63.5 -82.3  260  46 24   0.2   0.1 | -63.2 -81.8  260  39 20   0.1   0.1
 40000 -63.1 -81.6  260  54 28  -0.2  -0.1 | -63.0 -81.4  255  45 23  -0.2  -0.1
 38000 -58.3 -72.9  260  48 25   8.9   4.9 | -58.1 -72.6  250  44 23   9.1   5.0
 36000 -53.0 -63.4  260  41 21   8.9   4.9 | -52.6 -62.7  245  43 22   9.1   5.0
 34000 -47.7 -53.9  260  35 18   8.8   4.8 | -47.4 -53.3  245  42 22   8.4   4.6
 32000 -42.4 -44.3  250  32 17   8.8   4.8 | -41.7 -43.1  240  43 22   8.4   4.6
 30000 -36.4 -33.5  245  33 17   9.0   5.0 | -36.5 -33.7  240  41 21   8.9   4.9
 29000 -33.7 -28.7  245  34 17   9.0   5.0 | -33.8 -28.8  240  40 20   8.9   4.9
 28000 -31.0 -23.8  245  35 18   9.1   5.0 | -31.1 -24.0  240  38 20   8.9   4.9
 27000 -28.4 -19.1  240  34 17   8.1   4.5 | -28.5 -19.3  240  34 18   8.6   4.7
 26000 -26.0 -14.8  240  31 16   8.1   4.5 | -25.9 -14.6  240  30 15   8.6   4.7
 25000 -23.5 -10.3  235  29 15   8.1   4.4 | -23.3  -9.9  240  25 13   8.6   4.7
 24000 -21.3  -6.3  235  28 15   6.6   3.6 | -20.9  -5.6  240  24 12   7.8   4.3
 23000 -19.4  -2.9  230  28 15   6.6   3.6 | -18.5  -1.3  240  28 14   7.8   4.3
 22000 -17.4   0.7  230  28 15   6.6   3.6 | -16.2   2.8  235  32 16   7.8   4.3
 21000 -15.3   4.5  230  29 15   7.2   3.9 | -14.1   6.6  235  33 17   6.3   3.5
 20000 -13.2   8.2  225  31 16   7.2   4.0 | -12.2  10.0  235  33 17   6.3   3.5
 19500 -12.1  10.2  225  32 17   7.3   4.0 | -11.3  11.7  230  33 17   6.3   3.5
 19000 -11.0  12.2  225  33 17   7.2   3.9 | -10.3  13.5  230  33 17   6.4   3.5
 18500 -10.0  14.0  225  34 17   6.9   3.8 |  -9.3  15.3  230  33 17   6.7   3.7
 18000  -9.0  15.8  225  34 17   6.9   3.8 |  -8.3  17.1  225  33 17   6.7   3.7
 17500  -7.9  17.8  225  34 18   7.4   4.1 |  -7.3  18.9  225  34 17   6.9   3.8
 17000  -6.8  19.8  220  35 18   7.5   4.1 |  -6.3  20.7  220  34 17   7.0   3.8
 16500  -5.7  21.7  220  35 18   7.8   4.3 |  -5.3  22.5  215  34 18   7.4   4.1
 16000  -4.6  23.7  215  35 18   8.2   4.5 |  -4.2  24.4  210  34 17   8.3   4.5
 15500  -3.4  25.9  210  35 18   8.2   4.5 |  -2.4  27.7  205  34 17   8.5   4.7
 15000  -1.7  28.9  205  34 17   8.0   4.4 |  -1.1  30.0  200  33 17   8.7   4.8
 14500  -0.5  31.1  200  33 17   8.0   4.4 |   0.2  32.4  200  33 17   8.8   4.8
 14000   0.6  33.1  200  33 17   7.9   4.3 |   1.4  34.5  195  32 17   8.8   4.8
 13500   1.8  35.2  195  33 17   8.0   4.4 |   2.7  36.9  195  32 16   8.8   4.8
 13000   2.9  37.2  195  32 16   8.4   4.6 |   4.1  39.4  195  31 16   9.3   5.1
 12500   4.1  39.4  190  31 16   9.2   5.1 |   5.4  41.7  190  31 16   9.4   5.1
 12000   5.5  41.9  185  29 15   8.5   4.7 |   6.8  44.2  190  30 15   9.3   5.1
 11750   6.1  43.0  185  29 15   8.9   4.9 |   7.5  45.5  190  30 15   9.3   5.1
 11500   6.7  44.1  185  28 14   8.2   4.5 |   8.2  46.8  190  29 15   9.2   5.1
 11250   7.4  45.3  185  27 14  10.5   5.8 |   8.9  48.0  190  29 15   9.5   5.2
 11000   8.3  46.9  180  27 14  11.1   6.1 |   9.6  49.3  190  29 15   9.8   5.4
 10750   9.0  48.2  180  27 14   9.1   5.0 |  10.3  50.5  190  29 15   9.6   5.3
 10500   9.7  49.5  180  26 13   9.9   5.4 |  11.1  52.0  185  28 15  10.0   5.5
 10250  10.4  50.7  180  26 13   8.5   4.7 |  11.8  53.2  185  28 14   8.7   4.8
 10000  11.0  51.8  180  26 13   9.2   5.0 |  12.4  54.3  185  28 14   9.0   4.9
  9750  11.8  53.2  180  25 13  10.9   6.0 |  13.2  55.8  185  27 14  10.5   5.8
  9500  12.5  54.5  180  25 13  10.6   5.8 |  13.9  57.0  185  27 14  10.2   5.6
  9250  13.3  55.9  180  25 13  10.1   5.5 |  14.7  58.5  185  27 14   9.9   5.4
  9000  14.0  57.2  180  25 13   9.6   5.3 |  15.4  59.7  185  27 14   9.5   5.2
  8750  14.8  58.6  180  25 13  10.2   5.6 |  16.1  61.0  185  26 14   9.8   5.4
  8500  15.5  59.9  180  24 13  10.3   5.7 |  16.8  62.2  185  26 13   9.9   5.4
  8250  16.3  61.3  175  24 12  10.5   5.7 |  17.6  63.7  185  26 13  10.0   5.5
  8000  17.1  62.8  175  24 12  10.9   6.0 |  18.3  64.9  185  25 13  10.5   5.8
  7750  17.9  64.2  180  23 12  10.0   5.5 |  19.1  66.4  185  24 12   9.5   5.2
  7500  18.6  65.5  175  22 11   9.9   5.4 |  19.7  67.5  185  23 12   8.4   4.6
  7250  19.4  66.9  175  21 11  12.5   6.9 |  20.3  68.5  185  21 11   7.1   3.9
  7000  20.4  68.7  175  20 10  14.7   8.1 |  20.7  69.3  185  19 10   4.3   2.3
  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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