Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251103
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0502 MDT Saturday, July 25, 2015

This forecast is for Saturday, July 25, 2015:

If the trigger temperature of 75.1 F/24.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1260 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18231 ft MSL (11473 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 0845 MDT
Time of overdevelopment........................ 1200 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15544 ft MSL (8787 ft AGL)
Thermal soaring outlook for Sunday 07/26....... Good

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

Remarks...

Sunrise/Sunset.................... 05:53:41 / 20:17:34 MDT
Total possible sunshine........... 14 hr 23 min 53 sec (863 min 53 sec)
Altitude of sun at 13:05:28 MDT... 70.62 degrees

Upper air data from numerical model forecast valid on 07/25/2015 at 0600 MDT

Freezing level.................. 16169 ft MSL (9411 ft AGL)
Convective condensation level... 14167 ft MSL (7409 ft AGL)
Lifted condensation level....... 15468 ft MSL (8710 ft AGL)
Lifted index.................... -3.4
K index......................... +31.9

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  -68.0 -90.4   255   31   16   2.0   1.1      M     M       M      M    M
 45000  -62.2 -80.0   250   43   22   7.5   4.1      M     M       M      M    M
 40000  -50.3 -58.5   240   51   26   7.9   4.3      M     M       M      M    M
 38000  -45.6 -50.1   240   49   25   7.9   4.3      M     M       M      M    M
 36000  -40.9 -41.6   240   46   24   8.0   4.4      M     M       M      M    M
 34000  -36.0 -32.8   240   42   22   8.0   4.4      M     M       M      M    M
 32000  -31.2 -24.2   240   38   20   8.9   4.9      M     M       M      M    M
 30000  -26.8 -16.2   240   34   18   7.4   4.1   44.0 111.2    11.2      M    M
 29000  -24.0 -11.2   240   32   16   7.5   4.1   43.0 109.4    10.5      M    M
 28000  -21.9  -7.4   240   30   15   7.3   4.0   42.2 107.9    10.0      M    M
 27000  -19.7  -3.5   245   28   14   7.3   4.0   41.2 106.1     9.2      M    M
 26000  -17.5   0.5   245   26   14   7.3   4.0   40.3 104.5     8.6      M    M
 25000  -15.4   4.3   250   24   13   6.5   3.6   39.5 103.1     8.0      M    M
 24000  -13.6   7.5   250   23   12   6.1   3.3   38.1 100.5     6.9      M    M
 23000  -11.8  10.8   250   21   11   6.1   3.4   36.8  98.2     5.8      M    M
 22000  -10.0  14.0   245   19   10   5.9   3.2   35.6  96.0     4.8      M    M
 21000   -8.4  16.9   245   18    9   5.8   3.2   34.1  93.4     3.5      M    M
 20000   -6.7  19.9   250   17    9   5.9   3.2   32.8  91.0     2.3      M    M
 19500   -5.9  21.4   250   17    9   5.9   3.2   32.2  89.9     1.7      M    M
 19000   -5.1  22.8   250   16    8   5.7   3.1   31.5  88.6     1.1      M    M
 18500   -4.3  24.3   250   14    7   5.7   3.1   30.8  87.4     0.4      M    M
 18000   -3.5  25.7   250   13    7   5.9   3.2   30.1  86.2    -0.2   1047  5.3
 17500   -2.6  27.3   255   13    6   6.0   3.3   29.5  85.1    -0.8   1006  5.1
 17000   -1.7  28.9   255   12    6   6.1   3.4   28.9  84.0    -1.4    965  4.9
 16500   -0.8  30.6   260   12    6   6.8   3.7   28.3  83.0    -2.0    923  4.7
 16000    0.1  32.2   260   13    7   6.8   3.7   27.8  82.1    -2.5    879  4.5
 15500    1.1  34.0   260   15    7   7.3   4.0   27.4  81.3    -2.9    835  4.2
 15000    2.2  36.0   260   16    8   7.5   4.1   27.0  80.6    -3.4    788  4.0
 14500    3.9  39.0   255   17    9   9.2   5.1   26.6  79.9    -3.9    715  3.6
 14000    5.2  41.4   245   17    9   9.1   5.0   26.5  79.6    -4.1    662  3.4
 13500    6.4  43.5   245   17    9   8.8   4.8   26.4  79.4    -4.3    609  3.1
 13000    7.7  45.9   245   16    8   8.6   4.7   26.2  79.1    -4.5    556  2.8
 12500    9.0  48.2   240   16    8   9.4   5.2   26.1  79.0    -4.6    501  2.5
 12000   10.3  50.5   240   14    7   8.9   4.9   26.0  78.7    -4.8    448  2.3
 11750   11.0  51.8   240   14    7   8.5   4.7   25.9  78.6    -4.9    422  2.1
 11500   11.6  52.9   245   13    7   9.7   5.3   25.8  78.5    -5.0    395  2.0
 11250   12.3  54.1   245   13    7   9.1   5.0   25.8  78.5    -5.0    366  1.9
 11000   12.9  55.2   245   12    6   7.6   4.2   25.7  78.3    -5.2    341  1.7
 10750   13.5  56.3   245   11    6   7.9   4.3   25.6  78.0    -5.3    316  1.6
 10500   14.1  57.4   245   10    5   8.4   4.6   25.4  77.8    -5.5    291  1.5
 10250   14.7  58.5   250   10    5   9.4   5.1   25.4  77.7    -5.6    264  1.3
 10000   15.4  59.7   250    9    5   8.2   4.5   25.3  77.6    -5.6    237  1.2
  9750   16.0  60.8   255    8    4   7.4   4.1   25.1  77.3    -5.8    212  1.1
  9500   16.5  61.7   260    8    4   7.8   4.3   25.0  77.0    -6.0    188  1.0
  9250   17.1  62.8   265    8    4   8.0   4.4   24.8  76.7    -6.1    162  0.8
  9000   17.7  63.9   270    8    4   7.6   4.2   24.7  76.5    -6.3    137  0.7
  8750   18.3  64.9   280    8    4   7.1   3.9   24.5  76.1    -6.4    113  0.6
  8500   18.8  65.8   280    9    5   4.3   2.3   24.3  75.7    -6.7     91  0.5
  8250   19.0  66.2   285   10    5   0.4   0.2   23.7  74.6    -7.3     78  0.4
  8000   19.1  66.4   290   11    6   6.3   3.5   23.1  73.6    -7.8     66  0.3
  7750   19.3  66.7   295   12    6 -13.4  -7.3   22.5  72.5    -8.4     53  0.3
  7500   17.3  63.1   290   13    7 -22.5 -12.4   20.0  68.0   -11.0    106  0.5
  7250   16.4  61.5   290   11    6  -6.3  -3.4   18.8  65.8   -12.3    125  0.6
  7000   15.6  60.1   290    9    5 -20.2 -11.1   17.6  63.7   -13.5    144  0.7
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/25/2015 at 0900 MDT          |       07/25/2015 at 1200 MDT
                                           |
K index... +28.9  LI... +272.8             | K index... +26.0  LI... +273.6
CAPE... +28.1  CIN... -5.5                 | CAPE... +43.1  CIN... -48.1
                                           |
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 -67.2 -89.0  255  27 14   1.4   0.8 | -67.4 -89.3  240  29 15   2.5   1.4
 45000 -61.4 -78.5  255  41 21   7.5   4.1 | -60.7 -77.3  245  38 20   7.0   3.9
 40000 -50.2 -58.4  255  46 24   7.6   4.1 | -50.0 -58.0  250  45 23   7.7   4.2
 38000 -45.7 -50.3  250  42 22   7.6   4.1 | -45.3 -49.5  250  42 22   7.7   4.2
 36000 -41.2 -42.2  250  39 20   7.6   4.2 | -40.7 -41.3  250  40 20   7.7   4.2
 34000 -36.6 -33.9  245  37 19   7.6   4.2 | -36.1 -33.0  250  37 19   7.7   4.2
 32000 -32.1 -25.8  245  35 18   8.4   4.6 | -31.5 -24.7  250  34 18   8.0   4.4
 30000 -26.9 -16.4  245  33 17   7.7   4.2 | -26.8 -16.2  250  33 17   6.9   3.8
 29000 -24.7 -12.5  250  32 16   7.7   4.2 | -24.7 -12.5  245  33 17   7.0   3.8
 28000 -22.4  -8.3  250  31 16   7.2   4.0 | -22.6  -8.7  245  32 17   7.1   3.9
 27000 -20.3  -4.5  250  29 15   7.2   4.0 | -20.5  -4.9  250  31 16   7.1   3.9
 26000 -18.2  -0.8  250  28 15   7.3   4.0 | -18.4  -1.1  250  30 15   7.1   3.9
 25000 -16.0   3.2  250  27 14   7.1   3.9 | -16.3   2.7  250  29 15   6.9   3.8
 24000 -13.9   7.0  250  25 13   7.1   3.9 | -14.2   6.4  255  26 13   6.9   3.8
 23000 -11.8  10.8  250  23 12   7.1   3.9 | -12.1  10.2  260  23 12   7.0   3.8
 22000  -9.7  14.5  250  21 11   6.4   3.5 |  -9.9  14.2  265  21 11   7.3   4.0
 21000  -7.9  17.8  250  19 10   6.2   3.4 |  -7.7  18.1  265  20 10   7.4   4.1
 20000  -6.2  20.8  250  17  9   6.3   3.5 |  -5.5  22.1  265  19 10   7.4   4.1
 19500  -5.3  22.5  245  17  9   6.2   3.4 |  -4.4  24.1  270  18  9   7.1   3.9
 19000  -4.6  23.7  245  16  8   5.0   2.7 |  -3.6  25.5  265  18  9   5.1   2.8
 18500  -3.9  25.0  245  15  8   5.1   2.8 |  -2.8  27.0  265  17  9   5.6   3.1
 18000  -3.2  26.2  240  15  8   5.7   3.1 |  -2.1  28.2  265  16  8   5.4   2.9
 17500  -2.3  27.9  240  14  7   6.0   3.3 |  -1.5  29.3  265  15  8   5.3   2.9
 17000  -1.5  29.3  240  13  7   6.1   3.4 |  -0.9  30.4  265  14  7   5.6   3.1
 16500  -0.5  31.1  245  12  6   6.5   3.6 |  -0.1  31.8  265  12  6   6.1   3.3
 16000   0.4  32.7  245  11  6   6.5   3.5 |   0.8  33.4  265  11  5   6.0   3.3
 15500   1.4  34.5  250  10  5   7.3   4.0 |   1.7  35.1  265   9  5   6.8   3.7
 15000   2.5  36.5  250   9  5   7.5   4.1 |   3.1  37.6  275   7  4   6.8   3.7
 14500   4.1  39.4  255   9  4   8.6   4.7 |   4.2  39.6  280   6  3   7.8   4.3
 14000   5.4  41.7  255   8  4   8.5   4.6 |   5.3  41.5  290   4  2   7.8   4.3
 13500   6.6  43.9  255   8  4   8.6   4.7 |   6.4  43.5  320   3  2   7.2   4.0
 13000   7.9  46.2  265   7  4   8.7   4.8 |   7.5  45.5  005   4  2   7.1   3.9
 12500   9.1  48.4  280   6  3   8.3   4.6 |   8.6  47.5  020   7  4   8.1   4.4
 12000  10.3  50.5  290   6  3   8.4   4.6 |   9.8  49.6  025   9  5   8.3   4.6
 11750  10.9  51.6  295   6  3   8.1   4.5 |  10.4  50.7  025  10  5   8.1   4.5
 11500  11.5  52.7  300   6  3   9.0   5.0 |  11.0  51.8  025  11  6   9.3   5.1
 11250  12.2  54.0  305   7  3   8.6   4.7 |  11.7  53.1  025  12  6  10.0   5.5
 11000  12.8  55.0  310   7  3   7.3   4.0 |  12.4  54.3  020  12  6   9.4   5.2
 10750  13.3  55.9  315   7  4   7.6   4.1 |  13.0  55.4  020  12  6   9.5   5.2
 10500  13.9  57.0  320   7  4   7.6   4.2 |  13.7  56.7  020  12  6   9.9   5.4
 10250  14.5  58.1  325   7  4   7.9   4.4 |  14.5  58.1  020  12  6  10.4   5.7
 10000  15.1  59.2  330   8  4   7.0   3.8 |  15.3  59.5  020  12  6   9.7   5.3
  9750  15.5  59.9  335   9  4   6.3   3.4 |  16.0  60.8  020  12  6   9.3   5.1
  9500  16.0  60.8  335  10  5   6.2   3.4 |  16.7  62.1  020  12  6   9.6   5.3
  9250  16.5  61.7  340  10  5   5.8   3.2 |  17.4  63.3  020  12  6   9.7   5.3
  9000  16.9  62.4  340  11  6   5.9   3.3 |  18.1  64.6  020  12  6   9.9   5.4
  8750  17.3  63.1  345  12  6   6.0   3.3 |  18.9  66.0  020  12  6  10.8   5.9
  8500  17.8  64.0  345  13  7   7.1   3.9 |  19.7  67.5  020  12  6  10.7   5.9
  8250  18.3  64.9  345  14  7   8.2   4.5 |  20.5  68.9  020  12  6  10.6   5.8
  8000  18.8  65.8  345  14  7   7.0   3.8 |  21.2  70.2  020  12  6  10.1   5.5
  7750  19.4  66.9  340  14  7  10.7   5.9 |  22.0  71.6  020  12  6  12.2   6.7
  7500  20.2  68.4  340  13  7  10.4   5.7 |  23.0  73.4  020  11  6  13.2   7.2
  7250  20.7  69.3  340  12  6   5.5   3.0 |  23.8  74.8  020  11  6  11.4   6.3
  7000  21.2  70.2  340  11  6   9.5   5.2 |  24.7  76.5  020  11  6  13.0   7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/25/2015 at 1500 MDT          |       07/25/2015 at 1800 MDT
                                           |
K index... +24.4  LI... +272.5             | K index... +31.3  LI... +271.8
CAPE... +140.0  CIN... -4.1                | CAPE... +161.3  CIN... -7.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -67.7 -89.9  240  34 17   2.2   1.2 | -67.9 -90.2  240  37 19   2.1   1.1
 45000 -61.1 -78.0  245  43 22   7.5   4.1 | -61.4 -78.5  250  46 24   7.6   4.2
 40000 -49.8 -57.6  250  47 24   7.6   4.2 | -49.8 -57.6  250  49 25   8.0   4.4
 38000 -45.2 -49.4  245  44 23   7.6   4.2 | -45.0 -49.0  250  46 24   8.0   4.4
 36000 -40.6 -41.1  245  42 21   7.9   4.3 | -40.2 -40.4  250  44 23   7.9   4.4
 34000 -35.8 -32.4  250  39 20   8.1   4.4 | -35.5 -31.9  250  40 20   7.9   4.3
 32000 -30.9 -23.6  250  36 18   8.2   4.5 | -30.8 -23.4  250  35 18   8.1   4.5
 30000 -26.5 -15.7  250  36 18   6.6   3.6 | -26.2 -15.2  250  36 18   6.8   3.7
 29000 -24.5 -12.1  245  36 18   6.6   3.6 | -24.1 -11.4  250  36 19   6.8   3.8
 28000 -22.5  -8.5  245  35 18   6.8   3.7 | -22.1  -7.8  250  35 18   6.5   3.6
 27000 -20.5  -4.9  250  33 17   6.8   3.7 | -20.2  -4.4  250  33 17   6.5   3.6
 26000 -18.5  -1.3  250  31 16   6.8   3.8 | -18.2  -0.8  255  30 16   6.5   3.6
 25000 -16.5   2.3  255  30 15   6.6   3.6 | -16.3   2.7  255  28 14   6.6   3.6
 24000 -14.4   6.1  260  26 14   6.6   3.6 | -14.2   6.4  260  26 13   6.7   3.7
 23000 -12.4   9.7  265  23 12   6.7   3.7 | -12.2  10.0  265  23 12   6.7   3.7
 22000 -10.3  13.5  270  21 11   7.0   3.8 | -10.2  13.6  270  21 11   6.4   3.5
 21000  -8.2  17.2  275  20 10   7.1   3.9 |  -8.4  16.9  275  21 11   6.4   3.5
 20000  -6.1  21.0  280  20 10   7.1   3.9 |  -6.5  20.3  280  21 11   6.5   3.6
 19500  -5.0  23.0  285  20 10   7.0   3.8 |  -5.6  21.9  285  21 11   6.6   3.6
 19000  -4.0  24.8  285  20 10   6.7   3.7 |  -4.7  23.5  285  19 10   6.3   3.4
 18500  -3.0  26.6  285  20 10   6.9   3.8 |  -3.9  25.0  285  17  9   6.6   3.6
 18000  -2.1  28.2  290  20 10   5.8   3.2 |  -3.0  26.6  285  15  8   6.5   3.6
 17500  -1.4  29.5  285  19 10   5.7   3.1 |  -2.2  28.0  280  12  6   6.5   3.6
 17000  -0.7  30.7  285  18  9   6.1   3.3 |  -1.4  29.5  270   9  5   6.7   3.7
 16500   0.1  32.2  285  16  8   6.1   3.3 |  -0.4  31.3  270   6  3   7.0   3.8
 16000   0.8  33.4  290  12  6   6.3   3.5 |   0.6  33.1  275   3  1   6.9   3.8
 15500   1.6  34.9  295   9  5   6.0   3.3 |   1.6  34.9  015   1  0   7.7   4.2
 15000   2.4  36.3  320   5  3   6.1   3.4 |   2.8  37.0  065   3  1   7.8   4.3
 14500   3.9  39.0  020   4  2   9.2   5.0 |   4.6  40.3  070   5  3   9.6   5.3
 14000   5.2  41.4  040   6  3   8.8   4.8 |   5.9  42.6  075   5  3   9.4   5.2
 13500   6.5  43.7  045   7  4   9.9   5.4 |   7.3  45.1  070   6  3   9.4   5.2
 13000   8.0  46.4  045   7  4  10.0   5.5 |   8.7  47.7  070   6  3   9.4   5.2
 12500   9.4  48.9  045   7  4   9.5   5.2 |  10.1  50.2  070   6  3   9.6   5.3
 12000  10.9  51.6  045   7  4   9.9   5.4 |  11.5  52.7  070   6  3   9.5   5.2
 11750  11.6  52.9  045   7  4   9.8   5.4 |  12.2  54.0  070   6  3   9.1   5.0
 11500  12.4  54.3  045   7  4  10.8   5.9 |  13.0  55.4  070   6  3  11.0   6.1
 11250  13.2  55.8  045   7  4  10.1   5.6 |  13.8  56.8  070   6  3  10.8   5.9
 11000  13.9  57.0  045   7  4   8.8   4.9 |  14.5  58.1  070   6  3   8.8   4.8
 10750  14.5  58.1  045   7  4   8.9   4.9 |  15.2  59.4  070   6  3   9.1   5.0
 10500  15.2  59.4  045   7  4  10.0   5.5 |  15.9  60.6  065   6  3  10.0   5.5
 10250  16.0  60.8  045   7  4  11.1   6.1 |  16.7  62.1  065   6  3  11.0   6.1
 10000  16.8  62.2  045   7  4   9.8   5.4 |  17.4  63.3  065   6  3   9.4   5.2
  9750  17.5  63.5  045   7  4   9.1   5.0 |  18.1  64.6  065   6  3   8.4   4.6
  9500  18.2  64.8  045   7  4   9.8   5.4 |  18.8  65.8  065   6  3   9.4   5.2
  9250  18.9  66.0  045   7  4  10.2   5.6 |  19.5  67.1  065   6  3  10.2   5.6
  9000  19.7  67.5  045   7  4  10.1   5.5 |  20.3  68.5  065   6  3  10.0   5.5
  8750  20.4  68.7  045   7  4  10.1   5.5 |  21.0  69.8  065   5  3  10.2   5.6
  8500  21.2  70.2  045   7  4  10.4   5.7 |  21.7  71.1  065   5  3  10.1   5.5
  8250  22.0  71.6  045   7  4  10.8   5.9 |  22.5  72.5  065   5  3  10.0   5.5
  8000  22.8  73.0  045   7  4  10.2   5.6 |  23.2  73.8  065   5  3  10.1   5.5
  7750  23.6  74.5  045   7  3  12.0   6.6 |  24.0  75.2  065   5  3   9.9   5.4
  7500  24.5  76.1  045   7  3  12.7   6.9 |  24.7  76.5  065   5  3   8.5   4.7
  7250  25.3  77.5  045   7  3  11.2   6.1 |  25.2  77.4  060   5  3   7.6   4.1
  7000  26.2  79.2  045   7  3  12.5   6.8 |  25.8  78.4  060   5  3   8.3   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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