Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 241038
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0437 MDT Friday, July 24, 2015

This forecast is for Friday, July 24, 2015:

If the trigger temperature of 79.4 F/26.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 529 ft/min (2.7 m/s)
   Maximum height of thermals.................. 11740 ft MSL (4982 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8307 ft MSL (1550 ft AGL)
Thermal soaring outlook for Saturday 07/25..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:52:51 / 20:18:22 MDT
Total possible sunshine........... 14 hr 25 min 31 sec (865 min 31 sec)
Altitude of sun at 13:05:28 MDT... 70.83 degrees

Upper air data from numerical model forecast valid on 07/24/2015 at 0600 MDT

Freezing level.................. 16534 ft MSL (9776 ft AGL)
Convective condensation level... 16996 ft MSL (10238 ft AGL)
Lifted condensation level....... 16046 ft MSL (9289 ft AGL)
Lifted index.................... +0.4
K index......................... +28.8

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  -68.1 -90.6   260   34   18   2.0   1.1      M     M       M      M    M
 45000  -61.4 -78.5   260   47   24   7.8   4.3      M     M       M      M    M
 40000  -49.7 -57.5   255   54   28   7.8   4.3      M     M       M      M    M
 38000  -45.0 -49.0   255   53   27   7.8   4.3      M     M       M      M    M
 36000  -40.4 -40.7   260   51   26   7.4   4.0      M     M       M      M    M
 34000  -36.0 -32.8   260   44   23   7.2   3.9      M     M       M      M    M
 32000  -31.7 -25.1   255   37   19   7.7   4.2      M     M       M      M    M
 30000  -26.7 -16.1   255   33   17   7.5   4.1   43.2 109.7    12.8      M    M
 29000  -24.4 -11.9   250   31   16   7.5   4.1   42.4 108.4    12.4      M    M
 28000  -22.3  -8.1   250   29   15   6.8   3.7   41.5 106.7    11.8      M    M
 27000  -20.3  -4.5   245   28   14   6.9   3.8   40.3 104.6    10.9      M    M
 26000  -18.2  -0.8   245   26   13   6.9   3.8   39.3 102.7    10.1      M    M
 25000  -16.3   2.7   245   24   13   6.0   3.3   38.3 101.0     9.4      M    M
 24000  -14.6   5.7   240   23   12   5.7   3.1   36.7  98.1     8.1      M    M
 23000  -13.0   8.6   240   21   11   5.8   3.2   35.3  95.6     6.9      M    M
 22000  -11.3  11.7   235   19   10   6.4   3.5   34.0  93.2     5.8      M    M
 21000   -9.4  15.1   235   17    9   6.5   3.6   32.8  91.1     4.8      M    M
 20000   -7.6  18.3   230   15    8   6.6   3.6   31.7  89.1     3.8      M    M
 19500   -6.6  20.1   230   14    7   6.7   3.7   31.2  88.2     3.3      M    M
 19000   -5.6  21.9   225   12    6   7.1   3.9   30.8  87.4     2.9      M    M
 18500   -4.6  23.7   220   10    5   7.1   3.9   30.3  86.5     2.5      M    M
 18000   -3.6  25.5   215    8    4   7.4   4.1   29.9  85.8     2.0      M    M
 17500   -2.5  27.5   215    8    4   7.5   4.1   29.5  85.1     1.7      M    M
 17000   -1.4  29.5   210    8    4   7.8   4.3   29.1  84.4     1.3      M    M
 16500   -0.2  31.6   210    7    4   9.0   4.9   28.9  84.0     1.1      M    M
 16000    1.1  34.0   205    7    3   8.9   4.9   28.8  83.8     0.9      M    M
 15500    2.5  36.5   205    6    3   9.2   5.0   28.7  83.6     0.8      M    M
 15000    3.8  38.8   205    6    3   9.2   5.0   28.6  83.4     0.7      M    M
 14500    5.9  42.6   205    6    3   9.2   5.1   28.4  83.2     0.6      M    M
 14000    7.3  45.1   205    5    3   9.3   5.1   28.3  83.0     0.6      M    M
 13500    8.6  47.5   205    5    3   8.9   4.9   28.2  82.8     0.5      M    M
 13000   10.0  50.0   210    4    2   8.8   4.8   28.1  82.6     0.3      M    M
 12500   11.3  52.3   215    3    2   9.0   4.9   28.0  82.4     0.2      M    M
 12000   12.6  54.7   230    2    1   8.7   4.8   27.8  82.1     0.1      M    M
 11750   13.2  55.8   240    2    1   8.5   4.7   27.7  81.9    -0.0    422  2.1
 11500   13.9  57.0   265    1    1  10.1   5.5   27.7  81.8    -0.1    395  2.0
 11250   14.7  58.5   305    2    1   9.0   4.9   27.7  81.9    -0.0    364  1.8
 11000   15.2  59.4   335    2    1   6.9   3.8   27.5  81.6    -0.2    340  1.7
 10750   15.8  60.4   345    3    2   7.3   4.0   27.4  81.2    -0.4    317  1.6
 10500   16.3  61.3   350    4    2   8.4   4.6   27.2  80.9    -0.6    293  1.5
 10250   17.0  62.6   355    6    3   9.7   5.3   27.2  80.9    -0.6    265  1.3
 10000   17.7  63.9   355    7    3   7.5   4.1   27.1  80.8    -0.7    238  1.2
  9750   18.1  64.6   355    8    4   6.1   3.4   26.8  80.3    -0.9    216  1.1
  9500   18.6  65.5   360   10    5   6.9   3.8   26.6  79.9    -1.2    194  1.0
  9250   19.1  66.4   360   11    6   7.3   4.0   26.4  79.5    -1.4    172  0.9
  9000   19.7  67.5   360   12    6   6.7   3.7   26.2  79.1    -1.6    149  0.8
  8750   20.1  68.2   360   13    7   5.2   2.8   25.9  78.6    -1.9    128  0.7
  8500   20.3  68.5   355   13    7   1.2   0.7   25.4  77.8    -2.4    113  0.6
  8250   20.2  68.4   355   15    8  -2.4  -1.3   24.6  76.3    -3.3    109  0.6
  8000   20.1  68.2   350   17    9   2.2   1.2   23.8  74.8    -4.1    105  0.5
  7750   20.0  68.0   350   19   10 -12.7  -7.0   23.0  73.4    -4.9    101  0.5
  7500   18.3  64.9   340   19   10 -19.0 -10.4   20.8  69.4    -7.2    144  0.7
  7250   17.6  63.7   335   16    8  -6.2  -3.4   19.7  67.4    -8.4    160  0.8
  7000   16.8  62.2   330   13    7 -17.1  -9.4   18.5  65.3    -9.5    176  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/24/2015 at 0900 MDT          |       07/24/2015 at 1200 MDT
                                           |
K index... +27.8  LI... +272.3             | K index... +26.9  LI... +272.1
CAPE... +20.0  CIN... -18.0                | CAPE... +62.6  CIN... -26.8
                                           |
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 -67.5 -89.5  255  32 16   1.5   0.8 | -67.6 -89.7  250  32 16   2.0   1.1
 45000 -61.5 -78.7  260  44 23   7.5   4.1 | -61.2 -78.2  250  42 21   7.3   4.0
 40000 -50.2 -58.4  255  49 25   7.8   4.3 | -50.2 -58.4  250  47 24   7.7   4.2
 38000 -45.5 -49.9  255  49 25   7.8   4.3 | -45.6 -50.1  250  45 23   7.7   4.2
 36000 -40.8 -41.4  255  48 25   7.7   4.2 | -41.0 -41.8  245  44 23   7.8   4.3
 34000 -36.2 -33.2  255  45 23   7.6   4.2 | -36.2 -33.2  245  43 22   7.9   4.3
 32000 -31.6 -24.9  255  41 21   8.1   4.5 | -31.5 -24.7  250  41 21   8.7   4.8
 30000 -26.9 -16.4  250  37 19   7.1   3.9 | -26.6 -15.9  245  37 19   7.3   4.0
 29000 -24.7 -12.5  250  35 18   7.2   3.9 | -24.4 -11.9  245  34 18   7.3   4.0
 28000 -22.7  -8.9  245  33 17   6.8   3.7 | -22.4  -8.3  245  32 16   6.5   3.6
 27000 -20.7  -5.3  250  30 16   6.8   3.8 | -20.5  -4.9  240  28 15   6.5   3.6
 26000 -18.6  -1.5  250  28 14   6.9   3.8 | -18.5  -1.3  240  25 13   6.6   3.6
 25000 -16.7   1.9  250  26 13   6.2   3.4 | -16.6   2.1  240  22 11   6.4   3.5
 24000 -14.9   5.2  250  24 12   6.1   3.3 | -14.8   5.4  240  21 11   6.4   3.5
 23000 -13.1   8.4  250  22 11   6.1   3.3 | -12.9   8.8  240  19 10   6.4   3.5
 22000 -11.3  11.7  250  20 10   6.2   3.4 | -11.0  12.2  245  17  9   6.4   3.5
 21000  -9.5  14.9  245  17  9   6.3   3.5 |  -9.1  15.6  240  16  8   6.4   3.5
 20000  -7.7  18.1  235  14  7   6.3   3.5 |  -7.3  18.9  240  15  8   6.4   3.5
 19500  -6.8  19.8  230  13  7   6.5   3.6 |  -6.3  20.7  240  14  7   6.5   3.6
 19000  -5.8  21.6  225  12  6   6.9   3.8 |  -5.4  22.3  235  14  7   6.8   3.7
 18500  -4.9  23.2  215  11  6   6.9   3.8 |  -4.4  24.1  235  13  7   6.7   3.7
 18000  -3.8  25.2  210  10  5   7.5   4.1 |  -3.4  25.9  230  13  7   7.2   3.9
 17500  -2.7  27.1  205   9  5   7.7   4.2 |  -2.4  27.7  230  11  6   7.3   4.0
 17000  -1.6  29.1  200   9  5   7.9   4.4 |  -1.4  29.5  230  10  5   7.7   4.2
 16500  -0.3  31.5  200   9  5   8.8   4.8 |  -0.2  31.6  230   9  5   8.5   4.7
 16000   1.0  33.8  200   9  4   8.7   4.8 |   1.1  34.0  225   8  4   8.5   4.7
 15500   2.3  36.1  200   8  4   9.0   5.0 |   2.4  36.3  225   7  4   8.8   4.8
 15000   4.3  39.7  195   7  4   9.0   5.0 |   4.3  39.7  220   6  3   8.8   4.8
 14500   5.6  42.1  195   6  3   8.9   4.9 |   5.6  42.1  215   5  3   8.2   4.5
 14000   6.9  44.4  195   5  3   9.0   4.9 |   6.8  44.2  210   4  2   8.3   4.5
 13500   8.2  46.8  185   4  2   8.6   4.7 |   8.0  46.4  195   3  1   7.7   4.2
 13000   9.5  49.1  170   2  1   8.5   4.7 |   9.2  48.6  130   2  1   7.6   4.2
 12500  10.8  51.4  090   2  1   8.4   4.6 |  10.4  50.7  070   4  2   7.8   4.3
 12000  12.0  53.6  045   4  2   7.8   4.3 |  11.5  52.7  050   7  4   7.0   3.9
 11750  12.6  54.7  040   6  3   7.7   4.2 |  12.0  53.6  045   8  4   7.1   3.9
 11500  13.2  55.8  035   7  4   9.0   4.9 |  12.6  54.7  040  10  5   7.9   4.4
 11250  13.9  57.0  030  10  5   7.9   4.4 |  13.2  55.8  035  12  6   8.3   4.6
 11000  14.4  57.9  030  12  6   6.2   3.4 |  13.8  56.8  035  13  6   8.1   4.4
 10750  14.9  58.8  025  13  7   6.6   3.6 |  14.4  57.9  030  13  7   8.2   4.5
 10500  15.4  59.7  025  15  8   6.7   3.7 |  15.0  59.0  030  14  7   8.7   4.8
 10250  15.9  60.6  020  17  9   6.9   3.8 |  15.6  60.1  025  14  7   9.1   5.0
 10000  16.5  61.7  020  19 10   7.0   3.8 |  16.3  61.3  025  15  7   8.7   4.8
  9750  17.0  62.6  015  20 10   7.1   3.9 |  16.9  62.4  020  14  7   8.6   4.7
  9500  17.6  63.7  015  21 11   7.7   4.2 |  17.5  63.5  020  14  7   9.7   5.3
  9250  18.2  64.8  015  22 11   8.2   4.5 |  18.3  64.9  015  14  7  10.4   5.7
  9000  18.9  66.0  010  22 12   7.9   4.3 |  19.0  66.2  015  14  7   9.9   5.4
  8750  19.4  66.9  010  23 12   7.3   4.0 |  19.7  67.5  010  14  7   9.5   5.2
  8500  20.0  68.0  005  22 11   6.9   3.8 |  20.5  68.9  010  14  7  10.4   5.7
  8250  20.4  68.7  005  21 11   7.1   3.9 |  21.3  70.3  010  14  7  11.1   6.1
  8000  20.9  69.6  360  19 10   6.7   3.7 |  22.1  71.8  010  13  7  10.9   6.0
  7750  21.3  70.3  355  18  9   8.4   4.6 |  22.9  73.2  010  13  7  11.0   6.0
  7500  21.9  71.4  350  16  8   8.1   4.5 |  23.7  74.7  010  13  7  11.4   6.2
  7250  22.3  72.1  350  15  8   5.8   3.2 |  24.5  76.1  010  13  6  11.6   6.4
  7000  22.7  72.9  345  13  7   7.9   4.3 |  25.3  77.5  010  12  6  11.5   6.3
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/24/2015 at 1500 MDT          |       07/24/2015 at 1800 MDT
                                           |
K index... +29.8  LI... +271.3             | K index... +31.5  LI... +270.7
CAPE... +242.9  CIN... -1.9                | CAPE... +309.8  CIN... -14.0
                                           |
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 -68.2 -90.8  240  33 17   2.3   1.3 | -68.2 -90.8  240  32 17   2.3   1.2
 45000 -61.4 -78.5  245  42 21   7.4   4.1 | -61.8 -79.2  240  42 22   6.9   3.8
 40000 -50.1 -58.2  245  45 23   7.9   4.3 | -50.8 -59.4  245  45 23   8.7   4.8
 38000 -45.3 -49.5  245  44 23   7.9   4.3 | -45.6 -50.1  245  41 21   8.7   4.8
 36000 -40.6 -41.1  245  43 22   7.8   4.3 | -40.4 -40.7  245  36 19   8.6   4.7
 34000 -35.9 -32.6  245  42 21   7.8   4.3 | -35.3 -31.5  240  34 17   8.6   4.7
 32000 -31.2 -24.2  245  40 21   8.7   4.8 | -30.2 -22.4  240  31 16   9.4   5.2
 30000 -26.1 -15.0  245  35 18   7.7   4.2 | -24.9 -12.8  235  26 13   7.9   4.3
 29000 -23.8 -10.8  245  33 17   7.7   4.2 | -22.6  -8.7  235  24 12   7.9   4.3
 28000 -21.6  -6.9  245  31 16   7.0   3.8 | -20.4  -4.7  230  21 11   6.7   3.7
 27000 -19.6  -3.3  245  28 14   7.0   3.8 | -18.4  -1.1  225  19 10   6.7   3.7
 26000 -17.5   0.5  240  25 13   7.0   3.9 | -16.4   2.5  220  16  8   6.8   3.7
 25000 -15.5   4.1  240  23 12   6.6   3.6 | -14.5   5.9  210  14  7   6.1   3.4
 24000 -13.6   7.5  240  21 11   6.5   3.6 | -12.7   9.1  200  14  7   6.0   3.3
 23000 -11.7  10.9  245  19 10   6.5   3.6 | -11.0  12.2  190  14  7   6.0   3.3
 22000  -9.8  14.4  245  18  9   6.3   3.5 |  -9.2  15.4  180  14  7   5.5   3.0
 21000  -8.0  17.6  245  16  8   6.3   3.5 |  -7.7  18.1  170  14  7   5.4   3.0
 20000  -6.1  21.0  240  15  8   6.3   3.5 |  -6.1  21.0  160  15  8   5.4   3.0
 19500  -5.2  22.6  240  14  7   6.2   3.4 |  -5.3  22.5  160  15  8   5.4   3.0
 19000  -4.3  24.3  240  13  7   6.0   3.3 |  -4.6  23.7  155  15  8   5.1   2.8
 18500  -3.5  25.7  240  12  6   6.0   3.3 |  -3.9  25.0  155  14  7   5.1   2.8
 18000  -2.6  27.3  240  10  5   6.0   3.3 |  -3.1  26.4  150  13  7   5.6   3.1
 17500  -1.7  28.9  235   8  4   6.0   3.3 |  -2.3  27.9  145  11  6   5.8   3.2
 17000  -0.9  30.4  230   7  3   6.1   3.4 |  -1.5  29.3  140   9  5   5.8   3.2
 16500   0.1  32.2  220   5  3   6.6   3.6 |  -0.6  30.9  130   7  4   6.2   3.4
 16000   1.0  33.8  205   4  2   6.5   3.6 |   0.3  32.5  120   6  3   6.1   3.3
 15500   2.0  35.6  185   3  2   6.7   3.7 |   1.2  34.2  110   5  3   7.5   4.1
 15000   3.4  38.1  120   3  2   6.8   3.7 |   2.8  37.0  100   4  2   7.6   4.2
 14500   4.5  40.1  095   4  2   9.0   5.0 |   3.9  39.0  090   3  2   7.0   3.8
 14000   5.8  42.4  075   6  3   8.8   4.8 |   4.9  40.8  080   2  1   7.0   3.8
 13500   7.1  44.8  070   6  3   9.7   5.3 |   6.0  42.8  050   2  1   8.1   4.4
 13000   8.5  47.3  065   7  3   9.7   5.3 |   7.1  44.8  005   2  1   8.1   4.5
 12500   9.9  49.8  065   7  4   9.6   5.3 |   8.3  46.9  335   3  2   8.2   4.5
 12000  11.4  52.5  060   7  4  10.0   5.5 |   9.5  49.1  320   4  2   8.2   4.5
 11750  12.1  53.8  060   7  4  10.0   5.5 |  10.1  50.2  320   5  2   8.1   4.4
 11500  12.9  55.2  060   7  4  10.6   5.8 |  10.7  51.3  315   5  3   9.9   5.4
 11250  13.7  56.7  060   7  4  10.1   5.5 |  11.5  52.7  310   6  3   9.4   5.2
 11000  14.4  57.9  055   7  4   9.3   5.1 |  12.1  53.8  310   6  3   7.6   4.1
 10750  15.1  59.2  055   7  4   9.5   5.2 |  12.6  54.7  305   7  4   7.8   4.3
 10500  15.8  60.4  055   8  4   9.9   5.4 |  13.2  55.8  305   7  4   9.0   4.9
 10250  16.6  61.9  055   8  4  10.2   5.6 |  14.0  57.2  305   8  4  10.3   5.6
 10000  17.3  63.1  055   8  4   9.7   5.3 |  14.7  58.5  300   8  4   8.4   4.6
  9750  18.0  64.4  055   8  4   9.4   5.2 |  15.2  59.4  300   9  5   7.0   3.9
  9500  18.7  65.7  055   8  4   9.7   5.3 |  15.8  60.4  300  10  5   8.9   4.9
  9250  19.4  66.9  050   8  4   9.7   5.3 |  16.5  61.7  300  10  5  10.2   5.6
  9000  20.2  68.4  050   8  4  10.0   5.5 |  17.2  63.0  295  11  5   9.3   5.1
  8750  20.9  69.6  050   8  4  10.8   5.9 |  17.8  64.0  295  11  6   7.7   4.2
  8500  21.7  71.1  050   8  4  10.6   5.8 |  18.4  65.1  295  12  6   8.8   4.8
  8250  22.5  72.5  050   8  4  10.3   5.6 |  19.1  66.4  295  12  6  10.0   5.5
  8000  23.3  73.9  050   8  4  10.0   5.5 |  19.8  67.6  295  13  6  10.1   5.6
  7750  24.0  75.2  050   8  4  11.6   6.3 |  20.6  69.1  295  13  7   8.5   4.7
  7500  24.9  76.8  045   8  4  11.8   6.5 |  21.0  69.8  290  13  7   5.8   3.2
  7250  25.6  78.1  045   8  4  10.0   5.5 |  21.4  70.5  290  12  6   5.7   3.1
  7000  26.4  79.5  045   8  4  11.6   6.3 |  21.7  71.1  290  11  6   5.7   3.1
  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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