Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281007
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0407 MDT Thursday, July 28, 2016

This forecast is for Thursday, July 28, 2016:

If the trigger temperature of 79.2 F/26.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1278 ft/min (6.5 m/s)
   Maximum height of thermals.................. 19546 ft MSL (12788 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10864 ft MSL (4106 ft AGL)
Thermal soaring outlook for Friday 07/29....... Good

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

Remarks...

Sunrise/Sunset.................... 05:56:53 / 20:14:20 MDT
Total possible sunshine........... 14 hr 17 min 27 sec (857 min 27 sec)
Altitude of sun at 13:05:25 MDT... 69.77 degrees

Upper air data from numerical model forecast valid on 07/28/2016 at 0600 MDT

Freezing level.................. 16778 ft MSL (10020 ft AGL)
Convective condensation level... 15968 ft MSL (9210 ft AGL)
Lifted condensation level....... 15920 ft MSL (9162 ft AGL)
Lifted index.................... -5.6
K index......................... +23.9

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  -64.5 -84.1   295   23   12   2.0   1.1      M     M       M      M    M
 45000  -59.0 -74.2   295   42   22   6.6   3.6      M     M       M      M    M
 40000  -49.1 -56.4   290   44   23   4.9   2.7      M     M       M      M    M
 38000  -46.2 -51.2   300   44   23   4.9   2.7      M     M       M      M    M
 36000  -43.2 -45.8   310   45   23   5.8   3.2      M     M       M      M    M
 34000  -39.0 -38.2   310   41   21   7.1   3.9      M     M       M      M    M
 32000  -34.8 -30.6   315   38   19   7.3   4.0      M     M       M      M    M
 30000  -30.1 -22.2   315   34   17   7.9   4.4   39.9 103.7     8.1      M    M
 29000  -27.7 -17.9   320   32   16   8.0   4.4   39.2 102.6     7.7      M    M
 28000  -25.3 -13.5   320   30   16   7.3   4.0   38.6 101.5     7.3      M    M
 27000  -22.7  -8.9   325   30   16   7.1   3.9   37.3  99.1     6.3      M    M
 26000  -20.6  -5.1   325   30   16   7.1   3.9   36.3  97.4     5.6      M    M
 25000  -18.4  -1.1   325   30   16   7.0   3.8   35.5  95.8     5.0      M    M
 24000  -16.4   2.5   325   30   15   7.0   3.8   34.4  93.9     4.1      M    M
 23000  -14.3   6.3   325   30   15   7.0   3.8   33.4  92.1     3.3      M    M
 22000  -12.3   9.9   325   29   15   6.6   3.6   32.5  90.5     2.5      M    M
 21000  -10.4  13.3   320   26   13   6.7   3.7   31.3  88.4     1.4      M    M
 20000   -8.4  16.9   315   23   12   6.8   3.8   30.3  86.5     0.4      M    M
 19500   -7.5  18.5   310   21   11   7.4   4.1   29.8  85.7    -0.0   1277  6.5
 19000   -6.3  20.7   310   19   10   8.6   4.7   29.6  85.3    -0.3   1225  6.2
 18500   -5.0  23.0   305   17    9   8.5   4.6   29.4  84.9    -0.5   1173  6.0
 18000   -3.7  25.3   300   16    8   9.6   5.3   29.3  84.7    -0.6   1119  5.7
 17500   -2.3  27.9   300   15    8   9.8   5.4   29.2  84.6    -0.7   1061  5.4
 17000   -0.9  30.4   295   14    7   9.8   5.4   29.3  84.7    -0.7   1004  5.1
 16500    0.6  33.1   295   14    7   9.7   5.3   29.2  84.6    -0.7    946  4.8
 16000    2.0  35.6   290   14    7   9.7   5.3   29.2  84.6    -0.7    888  4.5
 15500    3.5  38.3   290   13    7   9.5   5.2   29.2  84.6    -0.8    830  4.2
 15000    4.8  40.6   285   12    6   9.5   5.2   29.2  84.5    -0.8    774  3.9
 14500    6.2  43.2   280   12    6   9.2   5.0   29.1  84.5    -0.9    718  3.6
 14000    8.1  46.6   270   11    5   9.1   5.0   29.0  84.1    -1.2    638  3.2
 13500    9.4  48.9   260   10    5   8.9   4.9   28.9  83.9    -1.4    585  3.0
 13000   10.7  51.3   255   11    5   9.1   5.0   28.7  83.7    -1.6    532  2.7
 12500   11.9  53.4   245   12    6   7.7   4.2   28.5  83.3    -1.8    482  2.4
 12000   13.0  55.4   245   13    7   8.0   4.4   28.2  82.8    -2.2    433  2.2
 11750   13.6  56.5   240   14    7   8.0   4.4   28.1  82.6    -2.3    408  2.1
 11500   14.2  57.6   240   14    7   8.2   4.5   28.0  82.3    -2.5    384  1.9
 11250   14.7  58.5   235   15    8   7.3   4.0   27.8  82.1    -2.6    359  1.8
 11000   15.2  59.4   235   15    8   6.5   3.6   27.6  81.7    -2.9    338  1.7
 10750   15.7  60.3   235   15    8   6.8   3.7   27.4  81.2    -3.2    317  1.6
 10500   16.1  61.0   235   15    8   6.8   3.7   27.1  80.8    -3.5    295  1.5
 10250   16.6  61.9   230   15    8   6.9   3.8   26.9  80.4    -3.7    273  1.4
 10000   17.1  62.8   230   15    8   6.6   3.6   26.7  80.0    -4.0    251  1.3
  9750   17.5  63.5   230   14    7   6.5   3.6   26.4  79.6    -4.3    231  1.2
  9500   18.0  64.4   230   13    7   6.6   3.6   26.2  79.1    -4.6    210  1.1
  9250   18.4  65.1   230   13    6   6.8   3.7   25.9  78.7    -4.9    190  1.0
  9000   18.9  66.0   235   12    6   6.6   3.6   25.7  78.3    -5.2    169  0.9
  8750   19.3  66.7   235   11    6   6.3   3.5   25.5  77.9    -5.5    149  0.8
  8500   19.6  67.3   230   10    5   2.3   1.2   25.1  77.2    -5.9    132  0.7
  8250   19.5  67.1   235    9    5  -1.4  -0.8   24.3  75.8    -6.7    127  0.6
  8000   19.5  67.1   235    8    4   1.9   1.0   23.6  74.5    -7.5    121  0.6
  7750   19.4  66.9   235    7    4  -7.5  -4.1   22.9  73.1    -8.3    116  0.6
  7500   18.5  65.3   240    7    4 -13.3  -7.3   21.3  70.3    -9.8    136  0.7
  7250   17.8  64.0   240    6    3  -7.1  -3.9   20.2  68.4   -10.9    149  0.8
  7000   17.1  62.8   245    5    3 -12.5  -6.9   19.2  66.5   -11.9    162  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/28/2016 at 0900 MDT          |       07/28/2016 at 1200 MDT
                                           |
K index... +10.6  LI... +270.4             | K index... +19.7  LI... +272.4
CAPE... +588.3  CIN... -96.2               | CAPE... +196.9  CIN... -8.1
                                           |
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 -64.3 -83.7  295  23 12   2.2   1.2 | -63.5 -82.3  285  18  9   1.5   0.8
 45000 -58.9 -74.0  300  35 18   6.0   3.3 | -59.1 -74.4  290  30 15   5.6   3.1
 40000 -50.1 -58.2  300  41 21   5.2   2.9 | -50.7 -59.3  300  45 23   5.7   3.1
 38000 -46.9 -52.4  300  43 22   5.2   2.9 | -47.3 -53.1  300  44 23   5.7   3.1
 36000 -43.8 -46.8  305  46 23   5.5   3.0 | -43.8 -46.8  295  44 23   5.8   3.2
 34000 -38.9 -38.0  305  42 21   7.4   4.0 | -39.1 -38.4  295  42 22   7.1   3.9
 32000 -34.4 -29.9  310  38 20   7.7   4.2 | -34.8 -30.6  295  40 21   7.5   4.1
 30000 -29.7 -21.5  305  33 17   7.8   4.3 | -30.1 -22.2  295  38 20   7.8   4.3
 29000 -27.4 -17.3  305  31 16   7.8   4.3 | -27.8 -18.0  295  37 19   7.8   4.3
 28000 -25.1 -13.2  305  29 15   7.3   4.0 | -25.4 -13.7  295  36 18   7.4   4.0
 27000 -22.8  -9.0  310  29 15   7.4   4.1 | -23.2  -9.8  295  34 18   7.4   4.1
 26000 -20.6  -5.1  315  29 15   7.4   4.1 | -21.0  -5.8  295  32 17   7.4   4.1
 25000 -18.4  -1.1  315  29 15   6.6   3.6 | -18.8  -1.8  295  30 16   6.5   3.6
 24000 -16.6   2.1  315  26 14   6.0   3.3 | -17.1   1.2  295  28 15   5.9   3.2
 23000 -14.8   5.4  320  24 12   6.1   3.3 | -15.3   4.5  295  26 13   6.0   3.3
 22000 -13.0   8.6  320  21 11   7.2   4.0 | -13.5   7.7  295  24 12   7.8   4.3
 21000 -10.8  12.6  315  20 10   7.7   4.2 | -11.0  12.2  300  24 12   8.6   4.7
 20000  -8.5  16.7  310  20 10   7.8   4.3 |  -8.5  16.7  300  24 12   8.6   4.7
 19500  -7.4  18.7  310  19 10   8.0   4.4 |  -7.2  19.0  305  24 12   8.6   4.7
 19000  -6.1  21.0  305  19 10   8.9   4.9 |  -6.0  21.2  300  24 12   8.6   4.7
 18500  -4.8  23.4  305  18  9   8.8   4.8 |  -4.7  23.5  300  23 12   8.6   4.7
 18000  -3.5  25.7  300  17  9   9.3   5.1 |  -3.4  25.9  300  23 12   8.6   4.7
 17500  -2.1  28.2  300  17  9   9.4   5.2 |  -2.2  28.0  300  22 11   8.7   4.8
 17000  -0.7  30.7  295  16  8   9.5   5.2 |  -0.9  30.4  300  20 10   8.8   4.8
 16500   0.8  33.4  295  16  8   9.7   5.3 |   1.2  34.2  300  19 10   9.4   5.2
 16000   3.0  37.4  295  16  8   9.7   5.3 |   2.6  36.7  300  18  9   9.5   5.2
 15500   4.5  40.1  295  16  8   9.8   5.4 |   4.0  39.2  300  17  9   9.8   5.4
 15000   5.9  42.6  295  16  8   9.8   5.4 |   5.5  41.9  300  16  8   9.8   5.4
 14500   7.4  45.3  295  17  9   9.6   5.3 |   6.9  44.4  300  16  8   9.6   5.3
 14000   8.8  47.8  295  17  9   9.6   5.3 |   8.3  46.9  305  15  8   9.6   5.3
 13500  10.3  50.5  295  17  9   9.3   5.1 |   9.7  49.5  305  15  8   9.6   5.3
 13000  11.6  52.9  295  18  9   9.4   5.1 |  11.2  52.2  310  14  7   9.6   5.3
 12500  13.0  55.4  295  18  9   9.2   5.1 |  12.6  54.7  310  13  7   9.6   5.3
 12000  14.4  57.9  295  19 10   9.4   5.2 |  14.0  57.2  315  13  6   9.7   5.3
 11750  15.1  59.2  295  19 10   9.4   5.2 |  14.7  58.5  320  12  6   9.6   5.3
 11500  15.8  60.4  295  19 10   9.7   5.3 |  15.4  59.7  320  12  6  10.8   5.9
 11250  16.5  61.7  295  19 10   9.4   5.2 |  16.3  61.3  320  12  6  10.4   5.7
 11000  17.2  63.0  295  19 10   9.0   4.9 |  17.0  62.6  325  11  6   9.2   5.1
 10750  17.8  64.0  295  19 10   9.2   5.1 |  17.7  63.9  325  11  6   9.4   5.2
 10500  18.5  65.3  290  19 10   8.8   4.8 |  18.3  64.9  330  11  6   9.9   5.4
 10250  19.1  66.4  290  18  9   8.4   4.6 |  19.1  66.4  330  11  5  10.4   5.7
 10000  19.7  67.5  290  18  9   7.9   4.4 |  19.8  67.6  335  10  5   9.6   5.3
  9750  20.2  68.4  285  18  9   7.9   4.3 |  20.5  68.9  335  10  5   9.1   5.0
  9500  20.7  69.3  285  18  9   6.8   3.7 |  21.2  70.2  340  10  5   9.5   5.2
  9250  21.1  70.0  280  18  9   5.9   3.2 |  22.0  71.6  340  10  5   9.7   5.3
  9000  21.5  70.7  280  17  9   5.4   3.0 |  22.7  72.9  340  10  5   9.9   5.4
  8750  21.8  71.2  275  17  9   3.2   1.8 |  23.4  74.1  345  10  5  10.8   5.9
  8500  21.9  71.4  275  17  9   2.0   1.1 |  24.2  75.6  345  10  5  10.6   5.8
  8250  21.9  71.4  270  16  8   2.6   1.4 |  25.0  77.0  345  10  5  10.2   5.6
  8000  21.9  71.4  265  14  7   0.9   0.5 |  25.8  78.4  345  10  5  10.2   5.6
  7750  22.0  71.6  260  13  7   8.2   4.5 |  26.5  79.7  345  10  5  10.7   5.9
  7500  22.8  73.0  255  11  6  10.1   5.6 |  27.4  81.3  350  10  5  12.1   6.7
  7250  23.1  73.6  250  10  5   3.0   1.6 |  28.3  82.9  350  10  5  12.8   7.0
  7000  23.4  74.1  245   9  4   9.1   5.0 |  29.2  84.6  350   9  5  12.4   6.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/28/2016 at 1500 MDT          |       07/28/2016 at 1800 MDT
                                           |
K index... +27.4  LI... +270.5             | K index... +30.0  LI... +269.8
CAPE... +772.7  CIN... -14.6               | CAPE... +944.4  CIN... -18.8
                                           |
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 -62.9 -81.2  270  19 10   1.1   0.6 | -63.6 -82.5  265  18  9   0.9   0.5
 45000 -59.1 -74.4  280  33 17   5.2   2.9 | -59.5 -75.1  280  32 17   5.9   3.2
 40000 -50.8 -59.4  295  50 25   5.8   3.2 | -50.8 -59.4  300  54 28   5.5   3.0
 38000 -47.3 -53.1  295  45 23   5.8   3.2 | -47.5 -53.5  300  47 24   5.5   3.0
 36000 -43.8 -46.8  295  41 21   6.3   3.4 | -44.2 -47.6  300  41 21   5.6   3.1
 34000 -39.6 -39.3  295  41 21   7.1   3.9 | -39.0 -38.2  300  38 20   7.8   4.3
 32000 -35.4 -31.7  290  40 20   7.3   4.0 | -34.4 -29.9  300  37 19   7.9   4.3
 30000 -30.9 -23.6  290  39 20   7.5   4.1 | -29.7 -21.5  300  35 18   7.8   4.3
 29000 -28.7 -19.7  290  39 20   7.5   4.1 | -27.3 -17.1  305  35 18   7.8   4.3
 28000 -26.4 -15.5  290  39 20   7.6   4.2 | -25.1 -13.2  305  35 18   6.7   3.7
 27000 -23.6 -10.5  290  39 20   7.6   4.2 | -23.0  -9.4  300  35 18   6.8   3.8
 26000 -21.3  -6.3  290  38 20   7.6   4.2 | -21.0  -5.8  300  35 18   6.8   3.8
 25000 -19.1  -2.4  290  37 19   6.5   3.6 | -18.9  -2.0  300  35 18   6.7   3.6
 24000 -17.3   0.9  290  35 18   6.2   3.4 | -17.0   1.4  295  35 18   6.6   3.6
 23000 -15.5   4.1  290  32 17   6.3   3.5 | -15.1   4.8  295  34 17   6.7   3.7
 22000 -13.5   7.7  295  30 15   8.7   4.8 | -13.2   8.2  290  33 17   8.0   4.4
 21000 -10.9  12.4  295  28 15   8.9   4.9 | -10.7  12.7  290  31 16   8.5   4.7
 20000  -8.3  17.1  295  27 14   9.0   4.9 |  -8.2  17.2  290  30 15   8.6   4.7
 19500  -7.0  19.4  295  26 13   9.1   5.0 |  -7.0  19.4  290  29 15   8.7   4.8
 19000  -5.7  21.7  290  25 13   9.3   5.1 |  -5.7  21.7  290  28 14   9.2   5.0
 18500  -4.3  24.3  290  24 12   9.3   5.1 |  -4.3  24.3  290  27 14   9.2   5.0
 18000  -2.9  26.8  290  23 12   9.5   5.2 |  -2.9  26.8  290  26 13   9.2   5.1
 17500  -1.5  29.3  290  22 11   9.5   5.2 |  -1.6  29.1  295  24 12   9.2   5.1
 17000  -0.1  31.8  290  21 11   9.6   5.2 |  -0.2  31.6  295  22 12   9.2   5.0
 16500   1.3  34.3  295  20 10   9.6   5.3 |   1.8  35.2  295  19 10   8.9   4.9
 16000   2.7  36.9  295  19 10   9.7   5.3 |   3.1  37.6  300  17  9   8.8   4.8
 15500   4.0  39.2  295  17  9   8.6   4.7 |   4.3  39.7  300  14  7   8.5   4.6
 15000   5.3  41.5  300  15  8   8.7   4.7 |   5.5  41.9  305  11  6   8.6   4.7
 14500   6.6  43.9  300  13  7   8.5   4.6 |   6.7  44.1  315   9  4   7.2   4.0
 14000   7.8  46.0  310  11  6   8.4   4.6 |   7.7  45.9  345   7  3   7.3   4.0
 13500   9.7  49.5  325   8  4   9.4   5.2 |   8.8  47.8  015   7  4   9.2   5.0
 13000  11.0  51.8  340   7  4   9.4   5.1 |  10.1  50.2  025   9  4   9.5   5.2
 12500  12.4  54.3  355   7  4   9.7   5.3 |  11.5  52.7  035  10  5   9.2   5.1
 12000  13.8  56.8  010   8  4   9.5   5.2 |  12.9  55.2  035  11  6   9.8   5.4
 11750  14.5  58.1  015   8  4   9.5   5.2 |  13.6  56.5  035  11  6   9.3   5.1
 11500  15.2  59.4  020   9  5  11.0   6.0 |  14.3  57.7  035  11  6  11.0   6.1
 11250  16.0  60.8  020   9  5  10.5   5.7 |  15.2  59.4  035  12  6  10.6   5.8
 11000  16.7  62.1  020   9  5   9.1   5.0 |  15.9  60.6  035  12  6   8.7   4.7
 10750  17.4  63.3  020   9  5   9.3   5.1 |  16.6  61.9  035  12  6   9.0   4.9
 10500  18.1  64.6  025  10  5  10.2   5.6 |  17.3  63.1  035  12  6   9.7   5.3
 10250  18.9  66.0  025   9  5  10.9   6.0 |  18.0  64.4  035  12  6  10.6   5.8
 10000  19.7  67.5  025  10  5   9.6   5.2 |  18.8  65.8  035  12  6   9.9   5.4
  9750  20.3  68.5  025  10  5   8.9   4.9 |  19.5  67.1  035  13  6   9.7   5.3
  9500  21.0  69.8  025  10  5   9.5   5.2 |  20.2  68.4  035  13  7   9.5   5.2
  9250  21.8  71.2  025  10  5   9.9   5.4 |  20.9  69.6  035  13  7   9.0   4.9
  9000  22.5  72.5  025  10  5   9.9   5.5 |  21.6  70.9  035  13  7   9.5   5.2
  8750  23.2  73.8  025  10  5  10.2   5.6 |  22.4  72.3  035  13  7  10.8   5.9
  8500  24.0  75.2  025  10  5  10.3   5.6 |  23.2  73.8  035  13  7  10.7   5.9
  8250  24.8  76.6  025  10  5  10.3   5.7 |  23.9  75.0  035  13  7  10.1   5.6
  8000  25.5  77.9  025  10  5  10.2   5.6 |  24.7  76.5  035  13  7  10.4   5.7
  7750  26.3  79.3  025  10  5  10.8   5.9 |  25.5  77.9  035  13  7   9.8   5.4
  7500  27.1  80.8  025  10  5  12.3   6.7 |  26.2  79.2  035  13  7   8.7   4.8
  7250  28.0  82.4  025  10  5  12.9   7.1 |  26.8  80.2  035  12  6   8.5   4.7
  7000  28.9  84.0  030  10  5  12.5   6.9 |  27.4  81.3  035  12  6   8.6   4.7
  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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