Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 041048
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0448 MDT Tuesday, August 4, 2015

This forecast is for Tuesday, August 4, 2015:

If the trigger temperature of 71.8 F/22.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1113 ft/min (5.7 m/s)
   Maximum height of thermals.................. 18715 ft MSL (11957 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14302 ft MSL (7544 ft AGL)
Thermal soaring outlook for Wednesday 08/05.... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:02:22 / 20:08:10 MDT
Total possible sunshine........... 14 hr 5 min 47 sec (845 min 47 sec)
Altitude of sun at 13:05:01 MDT... 68.20 degrees

Upper air data from numerical model forecast valid on 08/04/2015 at 0600 MDT

Freezing level.................. 15821 ft MSL (9063 ft AGL)
Convective condensation level... 15571 ft MSL (8813 ft AGL)
Lifted condensation level....... 16059 ft MSL (9301 ft AGL)
Lifted index.................... -4.5
K index......................... +15.9

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  -62.9 -81.2   260   34   17   3.0   1.6      M     M       M      M    M
 45000  -57.6 -71.7   270   52   27   4.8   2.6      M     M       M      M    M
 40000  -50.2 -58.4   275   50   26   4.5   2.5      M     M       M      M    M
 38000  -47.5 -53.5   275   45   23   4.5   2.5      M     M       M      M    M
 36000  -44.8 -48.6   275   40   20   4.1   2.2      M     M       M      M    M
 34000  -40.4 -40.7   280   38   20   7.8   4.3      M     M       M      M    M
 32000  -35.7 -32.3   280   38   19   7.7   4.2      M     M       M      M    M
 30000  -31.1 -24.0   280   36   18   7.6   4.2   39.2 102.5     8.8      M    M
 29000  -28.9 -20.0   280   34   18   7.6   4.2   38.4 101.1     8.3      M    M
 28000  -26.1 -15.0   280   33   17   6.8   3.7   37.5  99.4     7.7      M    M
 27000  -24.1 -11.4   280   30   16   6.7   3.7   36.2  97.2     6.7      M    M
 26000  -22.0  -7.6   280   28   14   6.7   3.7   35.1  95.1     5.9      M    M
 25000  -20.0  -4.0   280   25   13   6.9   3.8   34.1  93.3     5.1      M    M
 24000  -17.9  -0.2   275   22   11   7.4   4.1   33.1  91.6     4.4      M    M
 23000  -15.6   3.9   270   20   10   7.4   4.1   32.3  90.1     3.7      M    M
 22000  -13.4   7.9   265   17    9   7.0   3.8   31.6  88.8     3.1      M    M
 21000  -11.6  11.1   270   14    7   6.1   3.3   30.2  86.4     2.0      M    M
 20000   -9.8  14.4   275   12    6   6.1   3.3   29.0  84.2     1.0      M    M
 19500   -8.9  16.0   280   11    5   5.8   3.2   28.4  83.2     0.4      M    M
 19000   -7.8  18.0   285   10    5   9.0   4.9   28.0  82.5     0.1      M    M
 18500   -6.5  20.3   295   11    6   8.8   4.8   27.9  82.1    -0.1   1095  5.6
 18000   -5.1  22.8   300   12    6   8.4   4.6   27.7  81.9    -0.2   1041  5.3
 17500   -4.0  24.8   300   13    7   7.9   4.3   27.4  81.3    -0.5    991  5.0
 17000   -2.9  26.8   305   15    8   8.0   4.4   27.1  80.8    -0.8    942  4.8
 16500   -1.7  28.9   305   16    8   7.8   4.3   26.8  80.2    -1.2    894  4.5
 16000   -0.6  30.9   300   18    9   7.9   4.3   26.5  79.6    -1.5    845  4.3
 15500    0.5  32.9   300   20   10   7.8   4.3   26.2  79.1    -1.9    797  4.1
 15000    1.6  34.9   300   21   11   7.7   4.2   25.8  78.5    -2.3    751  3.8
 14500    2.6  36.7   300   23   12   7.7   4.2   25.5  77.9    -2.7    704  3.6
 14000    4.2  39.6   300   25   13   7.4   4.0   24.9  76.9    -3.4    636  3.2
 13500    5.2  41.4   300   26   13   7.6   4.2   24.6  76.2    -3.8    590  3.0
 13000    6.3  43.3   300   26   13   7.7   4.2   24.2  75.6    -4.2    543  2.8
 12500    7.4  45.3   300   26   14   7.2   3.9   23.9  75.1    -4.6    495  2.5
 12000    8.4  47.1   295   26   13   8.7   4.8   23.6  74.5    -5.0    449  2.3
 11750    9.0  48.2   295   25   13   8.3   4.5   23.5  74.3    -5.2    423  2.1
 11500    9.6  49.3   295   25   13   8.8   4.8   23.4  74.1    -5.3    398  2.0
 11250   10.3  50.5   295   24   12   9.4   5.1   23.4  74.1    -5.4    370  1.9
 11000   11.0  51.8   295   23   12   9.3   5.1   23.3  74.0    -5.4    343  1.7
 10750   11.7  53.1   290   23   12   9.3   5.1   23.3  73.9    -5.5    315  1.6
 10500   12.4  54.3   290   22   11   9.2   5.1   23.3  73.9    -5.5    287  1.5
 10250   13.0  55.4   290   21   11   9.0   4.9   23.2  73.8    -5.6    260  1.3
 10000   13.7  56.7   290   20   11   9.5   5.2   23.2  73.7    -5.7    233  1.2
  9750   14.4  57.9   285   20   10  10.2   5.6   23.2  73.7    -5.7    204  1.0
  9500   15.1  59.2   285   19   10   9.3   5.1   23.2  73.7    -5.8    175  0.9
  9250   15.8  60.4   285   18    9   8.3   4.5   23.1  73.6    -5.9    148  0.8
  9000   16.4  61.5   285   17    9   8.2   4.5   23.0  73.4    -6.0    122  0.6
  8750   17.0  62.6   285   17    9  10.1   5.5   22.9  73.3    -6.1     95  0.5
  8500   17.8  64.0   285   16    8   6.9   3.8   22.9  73.2    -6.1     66  0.3
  8250   18.1  64.6   285   16    8   2.7   1.5   22.5  72.4    -6.5     50  0.3
  8000   18.3  64.9   285   16    8   2.4   1.3   21.9  71.5    -7.1     36  0.2
  7750   18.5  65.3   285   17    9   4.9   2.7   21.4  70.6    -7.6     23  0.1
  7500   18.4  65.1   280   17    9 -11.6  -6.4   20.8  69.4    -8.3     16  0.1
  7250   16.6  61.9   280   14    7 -29.8 -16.3   18.6  65.5   -10.5     65  0.3
  7000   14.7  58.5   285   11    6 -15.8  -8.7   16.5  61.6   -12.8    114  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/04/2015 at 0900 MDT          |       08/04/2015 at 1200 MDT
                                           |
K index... +19.2  LI... +270.7             | K index... +22.7  LI... +270.6
CAPE... +336.9  CIN... -59.5               | CAPE... +480.8  CIN... -0.9
                                           |
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  260  35 18   2.9   1.6 | -61.0 -77.8  260  32 16   2.9   1.6
 45000 -57.3 -71.1  265  48 25   4.4   2.4 | -56.8 -70.2  265  45 23   2.5   1.3
 40000 -50.5 -58.9  275  46 23   4.4   2.4 | -52.4 -62.3  290  47 24   5.4   3.0
 38000 -47.9 -54.2  275  44 23   4.4   2.4 | -49.1 -56.4  290  48 25   5.5   3.0
 36000 -45.3 -49.5  275  42 22   3.9   2.2 | -45.8 -50.4  290  48 25   5.1   2.8
 34000 -40.9 -41.6  280  41 21   7.9   4.3 | -41.1 -42.0  290  48 24   8.2   4.5
 32000 -36.1 -33.0  280  39 20   7.8   4.3 | -36.2 -33.2  290  47 24   8.2   4.5
 30000 -31.5 -24.7  280  38 19   7.8   4.3 | -31.4 -24.5  295  42 22   8.0   4.4
 29000 -29.2 -20.6  285  37 19   7.8   4.3 | -29.0 -20.2  295  39 20   8.0   4.4
 28000 -26.9 -16.4  285  36 19   7.7   4.2 | -26.1 -15.0  295  36 19   7.5   4.1
 27000 -24.2 -11.6  280  35 18   7.4   4.1 | -23.8 -10.8  295  35 18   7.5   4.1
 26000 -22.0  -7.6  280  33 17   7.4   4.1 | -21.6  -6.9  295  34 18   7.5   4.1
 25000 -19.8  -3.6  280  32 16   7.3   4.0 | -19.4  -2.9  290  33 17   7.3   4.0
 24000 -17.7   0.1  280  30 16   7.1   3.9 | -17.4   0.7  285  32 16   6.7   3.7
 23000 -15.6   3.9  275  29 15   7.1   3.9 | -15.4   4.3  280  31 16   6.8   3.7
 22000 -13.6   7.5  275  27 14   6.8   3.7 | -13.4   7.9  275  30 16   6.7   3.7
 21000 -11.7  10.9  270  23 12   6.2   3.4 | -11.5  11.3  275  28 14   6.5   3.6
 20000  -9.9  14.2  260  19 10   6.2   3.4 |  -9.5  14.9  275  25 13   6.5   3.6
 19500  -9.0  15.8  255  17  9   6.0   3.3 |  -8.6  16.5  275  24 12   6.5   3.6
 19000  -8.0  17.6  255  16  8   8.1   4.4 |  -7.6  18.3  280  23 12   7.4   4.1
 18500  -6.9  19.6  260  15  7   7.9   4.3 |  -6.5  20.3  285  22 12   7.3   4.0
 18000  -5.7  21.7  265  14  7   7.7   4.2 |  -5.4  22.3  290  22 11   7.4   4.0
 17500  -4.6  23.7  270  13  7   7.6   4.2 |  -4.3  24.3  295  23 12   7.4   4.1
 17000  -3.4  25.9  280  13  6   7.5   4.1 |  -3.2  26.2  300  24 12   7.4   4.1
 16500  -2.2  28.0  285  12  6   8.5   4.7 |  -2.2  28.0  300  26 13   7.0   3.8
 16000  -1.0  30.2  290  13  7   8.4   4.6 |  -1.2  29.8  300  28 14   7.1   3.9
 15500   0.3  32.5  295  14  7   8.3   4.5 |  -0.3  31.5  300  28 15   7.2   4.0
 15000   1.5  34.7  300  16  8   8.2   4.5 |   0.7  33.3  295  25 13   7.5   4.1
 14500   2.7  36.9  305  17  9   8.2   4.5 |   1.6  34.9  290  22 11   8.4   4.6
 14000   4.5  40.1  305  21 11   8.3   4.5 |   3.6  38.5  290  19 10   9.6   5.3
 13500   5.7  42.3  305  23 12   8.2   4.5 |   5.0  41.0  290  18  9   9.8   5.4
 13000   6.9  44.4  300  25 13   8.2   4.5 |   6.5  43.7  290  17  9  10.0   5.5
 12500   8.1  46.6  295  27 14   8.6   4.7 |   7.9  46.2  290  17  9   9.3   5.1
 12000   9.3  48.7  295  28 14   7.5   4.1 |   9.4  48.9  290  16  8   9.9   5.4
 11750   9.9  49.8  295  28 14   7.1   3.9 |  10.1  50.2  290  16  8   9.5   5.2
 11500  10.4  50.7  295  28 15   9.4   5.1 |  10.8  51.4  290  16  8  11.0   6.0
 11250  11.2  52.2  290  28 14   9.5   5.2 |  11.7  53.1  290  15  8  10.7   5.9
 11000  11.8  53.2  290  27 14   7.3   4.0 |  12.4  54.3  290  15  8   9.1   5.0
 10750  12.3  54.1  290  27 14   7.6   4.2 |  13.1  55.6  290  15  8   9.5   5.2
 10500  12.9  55.2  285  26 14   8.0   4.4 |  13.8  56.8  290  15  8   9.6   5.3
 10250  13.5  56.3  285  26 13   8.9   4.9 |  14.5  58.1  290  14  7   9.8   5.4
 10000  14.1  57.4  285  25 13   8.2   4.5 |  15.2  59.4  290  14  7   9.8   5.4
  9750  14.6  58.3  280  25 13   7.5   4.1 |  16.0  60.8  290  14  7   9.8   5.4
  9500  15.1  59.2  280  24 12   7.6   4.2 |  16.7  62.1  290  14  7   9.6   5.3
  9250  15.6  60.1  280  23 12   7.3   4.0 |  17.4  63.3  290  14  7   9.3   5.1
  9000  16.2  61.2  280  22 12   7.5   4.1 |  18.1  64.6  290  13  7   9.7   5.3
  8750  16.7  62.1  280  21 11   8.6   4.7 |  18.8  65.8  290  13  7  10.7   5.9
  8500  17.3  63.1  275  20 10   8.2   4.5 |  19.7  67.5  290  13  7  10.8   5.9
  8250  17.8  64.0  275  18  9   7.5   4.1 |  20.4  68.7  295  12  6  10.6   5.8
  8000  18.3  64.9  275  16  8   6.8   3.8 |  21.2  70.2  295  12  6  10.4   5.7
  7750  18.8  65.8  275  14  7  10.1   5.5 |  22.0  71.6  295  12  6  11.3   6.2
  7500  19.6  67.3  275  11  6   9.5   5.2 |  22.9  73.2  295  11  6  12.1   6.7
  7250  20.0  68.0  275  10  5   4.9   2.7 |  23.7  74.7  295  11  5  11.8   6.5
  7000  20.3  68.5  270   8  4   8.7   4.8 |  24.6  76.3  295  10  5  12.2   6.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/04/2015 at 1500 MDT          |       08/04/2015 at 1800 MDT
                                           |
K index... +28.6  LI... +270.6             | K index... +26.0  LI... +271.3
CAPE... +459.5  CIN... -5.3                | CAPE... +296.6  CIN... -5.4
                                           |
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  260  27 14   2.4   1.3 | -62.9 -81.2  270  24 12   2.1   1.2
 45000 -57.7 -71.9  270  45 23   2.3   1.3 | -59.2 -74.6  280  39 20   3.4   1.9
 40000 -53.2 -63.8  290  54 28   6.6   3.6 | -53.1 -63.6  290  46 24   6.9   3.8
 38000 -49.3 -56.7  290  52 27   6.6   3.6 | -48.9 -56.0  290  46 24   6.9   3.8
 36000 -45.3 -49.5  290  51 26   6.6   3.6 | -44.8 -48.6  290  46 23   7.0   3.9
 34000 -40.6 -41.1  290  46 24   8.0   4.4 | -40.0 -40.0  290  42 22   8.0   4.4
 32000 -35.8 -32.4  295  40 21   7.8   4.3 | -35.2 -31.4  285  38 20   7.9   4.4
 30000 -30.8 -23.4  300  37 19   8.5   4.7 | -30.4 -22.7  290  33 17   8.0   4.4
 29000 -27.6 -17.7  300  35 18   8.5   4.7 | -27.4 -17.3  300  29 15   8.0   4.4
 28000 -25.1 -13.2  305  34 18   7.1   3.9 | -25.0 -13.0  300  28 14   7.9   4.4
 27000 -23.0  -9.4  305  32 17   7.2   4.0 | -22.6  -8.7  305  28 15   7.9   4.4
 26000 -20.8  -5.4  305  30 16   7.3   4.0 | -20.2  -4.4  305  29 15   7.9   4.4
 25000 -18.7  -1.7  305  28 14   6.8   3.7 | -17.9  -0.2  305  29 15   7.2   4.0
 24000 -16.9   1.6  300  27 14   6.0   3.3 | -15.9   3.4  305  27 14   6.5   3.6
 23000 -15.1   4.8  300  25 13   6.0   3.3 | -14.0   6.8  300  25 13   6.6   3.6
 22000 -13.4   7.9  295  24 12   6.5   3.6 | -12.1  10.2  300  23 12   6.3   3.4
 21000 -11.3  11.7  300  25 13   7.0   3.8 | -10.3  13.5  300  24 12   6.1   3.3
 20000  -9.3  15.3  300  26 13   7.0   3.9 |  -8.5  16.7  300  24 13   6.1   3.3
 19500  -8.2  17.2  300  26 13   7.0   3.9 |  -7.6  18.3  300  25 13   6.1   3.4
 19000  -7.2  19.0  300  27 14   7.2   3.9 |  -6.7  19.9  305  25 13   7.1   3.9
 18500  -6.2  20.8  300  28 15   7.2   3.9 |  -5.7  21.7  305  26 13   7.1   3.9
 18000  -5.1  22.8  295  30 15   7.7   4.2 |  -4.6  23.7  305  26 14   7.9   4.3
 17500  -4.0  24.8  295  29 15   8.2   4.5 |  -3.4  25.9  300  25 13   8.5   4.6
 17000  -2.9  26.8  290  27 14   8.3   4.6 |  -2.3  27.9  300  23 12   8.6   4.7
 16500  -1.7  28.9  290  25 13   8.8   4.8 |  -1.0  30.2  295  21 11   9.1   5.0
 16000  -0.5  31.1  285  22 11   8.8   4.8 |   0.2  32.4  290  20 10   9.2   5.0
 15500   0.8  33.4  285  20 10   9.3   5.1 |   1.5  34.7  290  18  9   9.4   5.2
 15000   2.2  36.0  285  18  9   9.5   5.2 |   2.9  37.2  290  17  9   9.5   5.2
 14500   4.3  39.7  285  16  8   9.8   5.4 |   5.0  41.0  290  16  8   9.8   5.4
 14000   5.7  42.3  285  16  8   9.8   5.4 |   6.4  43.5  290  16  8   9.8   5.4
 13500   7.2  45.0  290  15  8   9.9   5.4 |   7.9  46.2  295  16  8  10.0   5.5
 13000   8.6  47.5  290  15  8  10.0   5.5 |   9.4  48.9  295  16  8  10.3   5.7
 12500  10.1  50.2  290  15  8   9.6   5.3 |  10.7  51.3  295  15  8   8.8   4.8
 12000  11.5  52.7  290  15  8   9.7   5.3 |  12.2  54.0  295  15  8   9.8   5.4
 11750  12.3  54.1  290  14  7   9.8   5.4 |  13.0  55.4  295  15  8  10.0   5.5
 11500  13.0  55.4  290  14  7   9.6   5.3 |  13.7  56.7  295  15  7   9.5   5.2
 11250  13.7  56.7  290  14  7   9.7   5.3 |  14.4  57.9  295  14  7   9.6   5.3
 11000  14.4  57.9  290  14  7   9.9   5.4 |  15.1  59.2  295  14  7  10.1   5.5
 10750  15.2  59.4  290  14  7  10.0   5.5 |  15.9  60.6  300  14  7  10.2   5.6
 10500  15.9  60.6  290  14  7   9.5   5.2 |  16.6  61.9  300  14  7   9.4   5.2
 10250  16.6  61.9  290  14  7   8.9   4.9 |  17.3  63.1  300  14  7   8.6   4.7
 10000  17.3  63.1  295  13  7  10.2   5.6 |  17.9  64.2  300  13  7  10.0   5.5
  9750  18.1  64.6  295  13  7  11.3   6.2 |  18.7  65.7  300  13  7  11.2   6.1
  9500  18.9  66.0  295  13  7  10.2   5.6 |  19.5  67.1  300  13  7  10.1   5.5
  9250  19.6  67.3  295  13  7   8.8   4.9 |  20.2  68.4  300  13  7   8.8   4.8
  9000  20.3  68.5  295  13  7   9.4   5.2 |  20.9  69.6  300  13  7   9.2   5.1
  8750  21.0  69.8  295  13  6  11.0   6.0 |  21.7  71.1  305  12  6  10.3   5.6
  8500  21.9  71.4  295  12  6  10.9   6.0 |  22.4  72.3  305  12  6  10.5   5.7
  8250  22.6  72.7  295  12  6  10.3   5.6 |  23.2  73.8  305  12  6  10.3   5.6
  8000  23.4  74.1  295  12  6  10.3   5.6 |  23.9  75.0  305  12  6  10.2   5.6
  7750  24.2  75.6  295  11  6  10.7   5.9 |  24.7  76.5  305  11  6  10.7   5.8
  7500  25.0  77.0  300  11  6  11.7   6.4 |  25.4  77.7  305  11  6   8.6   4.7
  7250  25.8  78.4  300  10  5  12.1   6.6 |  25.9  78.6  310  10  5   6.2   3.4
  7000  26.7  80.1  300  10  5  11.9   6.5 |  26.4  79.5  310   9  5   8.1   4.5
  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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