Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 191014
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0414 MDT Friday, August 19, 2016

This forecast is for Friday, August 19, 2016:

If the trigger temperature of 66.2 F/19.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 351 ft/min (1.8 m/s)
   Maximum height of thermals.................. 13183 ft MSL (6425 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1045 MDT
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................. 9965 ft MSL (3208 ft AGL)
Thermal soaring outlook for Saturday 08/20..... Fair

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

Remarks...

Sunrise/Sunset.................... 06:16:37 / 19:48:50 MDT
Total possible sunshine........... 13 hr 32 min 12 sec (812 min 12 sec)
Altitude of sun at 13:02:22 MDT... 63.48 degrees

Upper air data from numerical model forecast valid on 08/19/2016 at 0600 MDT

Freezing level.................. 14665 ft MSL (7907 ft AGL)
Convective condensation level... 13004 ft MSL (6246 ft AGL)
Lifted condensation level....... 12690 ft MSL (5933 ft AGL)
Lifted index.................... -1.9
K index......................... +27.1

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  -59.9 -75.8   255   33   17   1.7   0.9      M     M       M      M    M
 45000  -57.5 -71.5   250   43   22   1.0   0.5      M     M       M      M    M
 40000  -55.6 -68.1   245   37   19   6.9   3.8      M     M       M      M    M
 38000  -51.9 -61.4   240   38   19   6.3   3.4      M     M       M      M    M
 36000  -48.1 -54.6   235   38   20   6.4   3.5      M     M       M      M    M
 34000  -43.1 -45.6   235   37   19   9.0   4.9      M     M       M      M    M
 32000  -37.7 -35.9   240   35   18   9.0   4.9      M     M       M      M    M
 30000  -31.9 -25.4   240   29   15   8.7   4.8   38.0 100.4    13.1      M    M
 29000  -29.3 -20.7   240   26   13   8.7   4.8   37.6  99.8    12.9      M    M
 28000  -26.7 -16.1   240   22   12   8.1   4.4   37.4  99.3    12.8      M    M
 27000  -24.5 -12.1   240   21   11   7.3   4.0   36.4  97.5    12.1      M    M
 26000  -22.4  -8.3   240   19   10   7.3   4.0   35.5  95.8    11.5      M    M
 25000  -20.2  -4.4   240   17    9   7.4   4.1   34.7  94.4    10.9      M    M
 24000  -18.1  -0.6   240   16    8   7.0   3.9   33.7  92.6    10.2      M    M
 23000  -16.0   3.2   240   15    8   7.1   3.9   32.7  90.8     9.4      M    M
 22000  -14.0   6.8   240   15    8   7.2   4.0   31.8  89.3     8.7      M    M
 21000  -12.2  10.0   250   13    7   5.7   3.1   30.5  86.8     7.6      M    M
 20000  -10.5  13.1   265   13    6   5.7   3.1   29.0  84.3     6.4      M    M
 19500   -9.7  14.5   270   12    6   5.7   3.1   28.4  83.1     5.9      M    M
 19000   -8.9  16.0   275   12    6   5.7   3.1   27.8  82.0     5.3      M    M
 18500   -8.0  17.6   285   12    6   5.7   3.1   27.0  80.7     4.7      M    M
 18000   -7.2  19.0   295   13    7   5.7   3.1   26.4  79.5     4.1      M    M
 17500   -6.3  20.7   300   13    7   6.4   3.5   25.8  78.4     3.6      M    M
 17000   -5.4  22.3   310   13    6   6.4   3.5   25.2  77.4     3.0      M    M
 16500   -4.4  24.1   315   13    6   6.9   3.8   24.7  76.4     2.5      M    M
 16000   -3.4  25.9   320   13    6   7.1   3.9   24.2  75.6     2.1      M    M
 15500   -2.4  27.7   325   13    7   7.5   4.1   23.8  74.8     1.7      M    M
 15000   -0.5  31.1   330   13    7   8.3   4.6   23.4  74.1     1.4      M    M
 14500    0.7  33.3   335   13    6   7.5   4.1   23.2  73.7     1.1      M    M
 14000    1.7  35.1   330   11    6   7.0   3.9   22.7  72.9     0.6      M    M
 13500    2.6  36.7   330   10    5   7.2   4.0   22.3  72.1     0.2      M    M
 13000    3.7  38.7   325    9    5   7.6   4.2   21.9  71.4    -0.2    525  2.7
 12500    4.8  40.6   315    9    4   7.0   3.9   21.6  70.9    -0.6    477  2.4
 12000    5.9  42.6   310    8    4   8.1   4.4   21.2  70.2    -1.0    431  2.2
 11750    6.4  43.5   305    8    4   8.0   4.4   21.1  69.9    -1.1    406  2.1
 11500    7.0  44.6   305    8    4   7.6   4.2   20.9  69.7    -1.3    382  1.9
 11250    7.5  45.5   305    8    4   6.4   3.5   20.7  69.3    -1.5    360  1.8
 11000    8.0  46.4   305    7    4   6.4   3.5   20.4  68.8    -1.8    339  1.7
 10750    8.4  47.1   310    7    4   6.8   3.7   20.2  68.3    -2.1    317  1.6
 10500    8.9  48.0   310    7    3   6.5   3.6   20.0  67.9    -2.3    296  1.5
 10250    9.3  48.7   315    7    3   5.3   2.9   19.7  67.4    -2.6    275  1.4
 10000    9.7  49.5   320    7    3   4.9   2.7   19.3  66.7    -3.0    257  1.3
  9750   10.1  50.2   320    7    3   5.8   3.2   19.0  66.1    -3.4    239  1.2
  9500   10.5  50.9   325    7    4   4.6   2.5   18.6  65.5    -3.7    220  1.1
  9250   10.7  51.3   330    8    4   1.4   0.8   18.1  64.6    -4.3    206  1.0
  9000   10.7  51.3   330    9    5   0.2   0.1   17.4  63.3    -5.0    199  1.0
  8750   10.6  51.1   330   10    5  -1.9  -1.0   16.6  61.9    -5.8    193  1.0
  8500   10.4  50.7   330   12    6  -0.5  -0.3   15.7  60.3    -6.8    193  1.0
  8250   10.5  50.9   335   12    6   4.5   2.4   15.2  59.3    -7.4    182  0.9
  8000   10.8  51.4   335   13    7   3.6   2.0   14.8  58.6    -7.9    166  0.8
  7750   11.1  52.0   335   13    7   7.9   4.3   14.4  57.9    -8.3    150  0.8
  7500   11.7  53.1   335   14    7   5.9   3.3   14.4  57.8    -8.4    123  0.6
  7250   11.8  53.2   335   12    6  -1.4  -0.8   14.1  57.4    -8.7    114  0.6
  7000   11.8  53.2   335   10    5   4.5   2.5   13.8  56.9    -9.0    105  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/19/2016 at 0900 MDT          |       08/19/2016 at 1200 MDT
                                           |
K index... +24.8  LI... +271.3             | K index... +25.7  LI... +270.4
CAPE... +372.7  CIN... -52.7               | CAPE... +622.6  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 -59.6 -75.3  255  33 17   1.9   1.0 | -59.7 -75.5  260  31 16   1.7   0.9
 45000 -57.2 -71.0  255  43 22   0.6   0.3 | -57.6 -71.7  255  39 20   0.2   0.1
 40000 -55.9 -68.6  245  34 17   7.2   3.9 | -56.7 -70.1  240  36 18   8.5   4.7
 38000 -52.0 -61.6  245  30 15   6.4   3.5 | -52.2 -62.0  240  31 16   7.6   4.2
 36000 -48.2 -54.8  245  26 13   6.5   3.6 | -47.6 -53.7  245  25 13   7.6   4.2
 34000 -43.4 -46.1  240  26 13   8.6   4.7 | -42.7 -44.9  245  24 12   8.5   4.7
 32000 -38.2 -36.8  240  27 14   8.6   4.7 | -37.6 -35.7  245  24 13   8.5   4.7
 30000 -32.4 -26.3  245  24 12   8.8   4.8 | -32.0 -25.6  250  23 12   8.2   4.5
 29000 -29.8 -21.6  250  22 11   8.8   4.8 | -29.6 -21.3  255  22 11   8.2   4.5
 28000 -27.2 -17.0  255  20 10   8.3   4.6 | -27.1 -16.8  260  22 11   8.0   4.4
 27000 -24.9 -12.8  255  19 10   7.6   4.2 | -24.9 -12.8  260  20 10   7.5   4.1
 26000 -22.6  -8.7  255  19 10   7.6   4.2 | -22.7  -8.9  265  19 10   7.5   4.1
 25000 -20.4  -4.7  255  18  9   7.7   4.2 | -20.4  -4.7  275  17  9   7.6   4.2
 24000 -18.1  -0.6  255  17  9   7.4   4.1 | -18.3  -0.9  280  17  9   7.0   3.9
 23000 -15.9   3.4  260  16  8   7.4   4.1 | -16.2   2.8  285  17  9   7.0   3.9
 22000 -13.7   7.3  260  16  8   7.6   4.2 | -14.1   6.6  295  17  9   7.2   3.9
 21000 -11.9  10.6  265  15  7   5.5   3.0 | -12.3   9.9  305  17  9   6.2   3.4
 20000 -10.3  13.5  275  13  7   5.5   3.0 | -10.4  13.3  310  17  9   6.3   3.4
 19500  -9.5  14.9  275  13  7   5.5   3.0 |  -9.5  14.9  315  17  9   6.3   3.4
 19000  -8.7  16.3  280  12  6   4.9   2.7 |  -8.6  16.5  320  17  9   6.2   3.4
 18500  -8.0  17.6  290  12  6   4.6   2.5 |  -7.7  18.1  320  17  9   6.1   3.3
 18000  -7.3  18.9  295  11  6   4.6   2.5 |  -6.8  19.8  320  17  9   6.1   3.4
 17500  -6.6  20.1  300  11  6   5.1   2.8 |  -6.0  21.2  325  17  9   6.0   3.3
 17000  -5.9  21.4  305  11  6   5.2   2.8 |  -5.1  22.8  325  16  8   6.0   3.3
 16500  -5.2  22.6  310  11  6   7.0   3.8 |  -4.2  24.4  330  16  8   5.9   3.3
 16000  -4.1  24.6  315  12  6   7.6   4.2 |  -3.3  26.1  335  16  8   5.9   3.3
 15500  -3.1  26.4  320  12  6   8.0   4.4 |  -2.5  27.5  335  16  8   6.0   3.3
 15000  -1.2  29.8  320  12  6   8.6   4.7 |  -1.2  29.8  340  17  9   6.1   3.4
 14500  -0.0  32.0  320  12  6   8.4   4.6 |  -0.3  31.5  340  17  9   6.4   3.5
 14000   1.2  34.2  315  12  6   8.3   4.5 |   0.7  33.3  340  17  9   6.7   3.7
 13500   2.4  36.3  315  11  6   8.3   4.6 |   1.6  34.9  340  18  9   6.8   3.7
 13000   3.6  38.5  310  11  6   8.4   4.6 |   2.6  36.7  340  16  8   7.1   3.9
 12500   4.8  40.6  305  10  5   8.0   4.4 |   3.6  38.5  335  15  8   7.8   4.3
 12000   5.9  42.6  305  10  5   7.8   4.3 |   4.7  40.5  335  11  6   8.4   4.6
 11750   6.4  43.5  300  10  5   7.9   4.3 |   5.3  41.5  330   9  5   8.7   4.8
 11500   7.0  44.6  300  10  5   7.4   4.0 |   5.9  42.6  325   8  4   8.0   4.4
 11250   7.5  45.5  295   9  5   6.6   3.6 |   6.4  43.5  320   6  3   8.2   4.5
 11000   7.9  46.2  295   9  4   7.0   3.8 |   7.0  44.6  315   5  3   9.7   5.3
 10750   8.5  47.3  295   8  4   7.3   4.0 |   7.8  46.0  315   4  2   9.9   5.4
 10500   9.0  48.2  290   7  4   7.1   3.9 |   8.5  47.3  310   4  2   9.8   5.4
 10250   9.5  49.1  290   7  3   6.2   3.4 |   9.2  48.6  305   3  2   8.8   4.8
 10000   9.9  49.8  285   6  3   6.9   3.8 |   9.8  49.6  300   3  1   9.7   5.3
  9750  10.5  50.9  285   6  3   8.3   4.5 |  10.6  51.1  295   2  1  11.3   6.2
  9500  11.0  51.8  285   5  3   7.5   4.1 |  11.4  52.5  285   2  1  10.5   5.7
  9250  11.5  52.7  285   5  3   6.1   3.4 |  12.1  53.8  275   2  1   9.1   5.0
  9000  11.9  53.4  285   6  3   5.5   3.0 |  12.8  55.0  265   1  1   8.8   4.8
  8750  12.3  54.1  285   7  3   4.6   2.5 |  13.5  56.3  255   1  1  10.8   5.9
  8500  12.6  54.7  285   7  4   4.5   2.5 |  14.3  57.7  230   1  1  11.3   6.2
  8250  12.9  55.2  285   7  4   5.7   3.1 |  15.1  59.2  215   1  1  10.5   5.7
  8000  13.3  55.9  295   6  3   5.2   2.8 |  15.9  60.6  200   1  1  10.3   5.7
  7750  13.7  56.7  305   5  3   7.4   4.0 |  16.7  62.1  195   2  1  10.7   5.9
  7500  14.3  57.7  320   4  2   9.6   5.3 |  17.5  63.5  185   2  1  12.3   6.8
  7250  15.0  59.0  325   4  2   8.8   4.9 |  18.4  65.1  180   2  1  13.5   7.4
  7000  15.6  60.1  330   4  2   9.6   5.3 |  19.4  66.9  175   2  1  12.8   7.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/19/2016 at 1500 MDT          |       08/19/2016 at 1800 MDT
                                           |
K index... +19.7  LI... +270.3             | K index... +32.0  LI... +270.0
CAPE... +525.7  CIN... -3.7                | CAPE... +621.3  CIN... -1.3
                                           |
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 -60.0 -76.0  250  31 16   1.8   1.0 | -60.3 -76.5  255  36 18   1.4   0.8
 45000 -57.7 -71.9  255  39 20   0.4   0.2 | -58.5 -73.3  250  41 21   0.3   0.2
 40000 -56.5 -69.7  250  45 23   8.2   4.5 | -57.2 -71.0  250  43 22   9.1   5.0
 38000 -52.0 -61.6  245  39 20   7.5   4.1 | -52.1 -61.8  245  38 20   8.5   4.7
 36000 -47.5 -53.5  240  34 17   7.5   4.1 | -47.0 -52.6  245  34 17   8.5   4.7
 34000 -42.5 -44.5  245  30 16   8.7   4.8 | -41.8 -43.2  250  30 16   8.8   4.9
 32000 -37.2 -35.0  250  28 14   8.7   4.8 | -36.5 -33.7  260  27 14   8.9   4.9
 30000 -31.6 -24.9  260  26 13   8.2   4.5 | -31.1 -24.0  270  25 13   7.8   4.3
 29000 -29.2 -20.6  270  25 13   8.2   4.5 | -28.7 -19.7  280  24 12   7.8   4.3
 28000 -26.7 -16.1  275  24 13   8.0   4.4 | -26.4 -15.5  285  23 12   7.5   4.1
 27000 -24.4 -11.9  280  23 12   7.6   4.2 | -24.3 -11.7  290  21 11   7.2   3.9
 26000 -22.2  -8.0  285  23 12   7.6   4.2 | -22.2  -8.0  295  19 10   7.2   4.0
 25000 -19.9  -3.8  290  22 11   7.7   4.2 | -20.1  -4.2  305  18  9   7.3   4.0
 24000 -17.6   0.3  295  21 11   7.5   4.1 | -18.1  -0.6  310  19 10   6.5   3.6
 23000 -15.4   4.3  300  20 10   7.5   4.1 | -16.2   2.8  310  21 11   6.6   3.6
 22000 -13.2   8.2  310  19 10   7.8   4.3 | -14.2   6.4  310  23 12   6.6   3.6
 21000 -11.6  11.1  315  20 10   4.7   2.6 | -12.4   9.7  310  22 12   6.3   3.5
 20000 -10.2  13.6  325  21 11   4.7   2.6 | -10.5  13.1  310  21 11   6.3   3.5
 19500  -9.4  15.1  325  22 11   4.7   2.6 |  -9.6  14.7  310  21 11   6.4   3.5
 19000  -8.7  16.3  330  23 12   5.8   3.2 |  -8.7  16.3  315  20 10   6.1   3.3
 18500  -7.8  18.0  330  24 12   6.4   3.5 |  -7.8  18.0  320  17  9   6.0   3.3
 18000  -6.8  19.8  335  25 13   6.4   3.5 |  -7.0  19.4  325  15  8   6.0   3.3
 17500  -5.8  21.6  335  26 13   7.2   3.9 |  -6.1  21.0  340  13  7   6.5   3.6
 17000  -4.8  23.4  340  26 14   7.1   3.9 |  -5.2  22.6  355  12  6   6.5   3.5
 16500  -3.8  25.2  340  27 14   6.9   3.8 |  -4.2  24.4  015  12  6   6.8   3.7
 16000  -2.8  27.0  340  26 14   6.9   3.8 |  -3.2  26.2  020  13  7   7.0   3.8
 15500  -1.8  28.8  340  26 13   6.8   3.7 |  -2.3  27.9  025  13  7   6.9   3.8
 15000  -0.5  31.1  345  22 11   6.8   3.7 |  -0.8  30.6  025  14  7   6.6   3.6
 14500   0.4  32.7  345  19 10   7.6   4.2 |   0.1  32.2  025  15  8   6.8   3.7
 14000   1.5  34.7  350  16  8   8.3   4.5 |   1.1  34.0  025  16  8   7.1   3.9
 13500   2.6  36.7  350  13  7   8.7   4.8 |   2.1  35.8  025  16  8   7.8   4.3
 13000   3.9  39.0  355  12  6   9.5   5.2 |   3.4  38.1  025  16  8   9.4   5.1
 12500   5.3  41.5  360  10  5   8.9   4.9 |   4.8  40.6  025  16  8   8.1   4.4
 12000   6.6  43.9  360   9  5   8.8   4.9 |   6.0  42.8  025  17  9  10.4   5.7
 11750   7.2  45.0  360   9  4   9.0   4.9 |   6.8  44.2  025  17  9   9.8   5.4
 11500   7.9  46.2  005   8  4   8.2   4.5 |   7.5  45.5  025  17  9  10.1   5.6
 11250   8.4  47.1  005   7  4   8.4   4.6 |   8.2  46.8  025  16  8  10.0   5.5
 11000   9.1  48.4  005   6  3   9.7   5.3 |   9.0  48.2  025  16  8   9.6   5.2
 10750   9.8  49.6  010   5  3   9.7   5.3 |   9.7  49.5  025  16  8   9.6   5.3
 10500  10.5  50.9  015   4  2   9.7   5.3 |  10.4  50.7  025  16  8   9.5   5.2
 10250  11.2  52.2  020   4  2   7.2   4.0 |  11.1  52.0  025  16  8   8.2   4.5
 10000  11.7  53.1  025   3  1   8.6   4.7 |  11.7  53.1  025  16  8   9.1   5.0
  9750  12.5  54.5  035   3  1  11.5   6.3 |  12.4  54.3  025  16  8  10.7   5.9
  9500  13.3  55.9  045   2  1  10.6   5.8 |  13.2  55.8  025  16  8  10.1   5.6
  9250  14.0  57.2  055   2  1   9.7   5.3 |  13.9  57.0  025  16  8   9.4   5.1
  9000  14.7  58.5  060   2  1   9.3   5.1 |  14.6  58.3  020  16  8   9.2   5.1
  8750  15.5  59.9  065   2  1  10.4   5.7 |  15.3  59.5  020  16  8  10.6   5.8
  8500  16.2  61.2  075   2  1  10.8   5.9 |  16.1  61.0  020  16  8  10.8   5.9
  8250  17.0  62.6  085   2  1  10.4   5.7 |  16.9  62.4  020  15  8   9.9   5.4
  8000  17.8  64.0  095   2  1  10.8   5.9 |  17.6  63.7  020  15  8   9.7   5.3
  7750  18.6  65.5  105   2  1   9.5   5.2 |  18.3  64.9  020  14  7   9.7   5.3
  7500  19.3  66.7  110   2  1  10.4   5.7 |  19.0  66.2  020  14  7   8.1   4.5
  7250  20.2  68.4  110   2  1  13.5   7.4 |  19.5  67.1  020  13  6   6.5   3.6
  7000  21.1  70.0  110   2  1  12.7   7.0 |  19.9  67.8  020  11  6   7.1   3.9
  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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