Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 021126
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0526 MDT Wednesday, September 2, 2015

This forecast is for Wednesday, September 2, 2015:

If the trigger temperature of 74.2 F/23.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1316 ft/min (6.7 m/s)
   Maximum height of thermals.................. 19535 ft MSL (12777 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15153 ft MSL (8396 ft AGL)
Thermal soaring outlook for Thursday 09/03..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:28:33 / 19:29:32 MDT
Total possible sunshine........... 13 hr 0 min 59 sec (780 min 59 sec)
Altitude of sun at 12:58:37 MDT... 58.87 degrees

Upper air data from numerical model forecast valid on 09/02/2015 at 0600 MDT

Freezing level.................. 15896 ft MSL (9138 ft AGL)
Convective condensation level... 15633 ft MSL (8875 ft AGL)
Lifted condensation level....... 16468 ft MSL (9710 ft AGL)
Lifted index.................... -3.4
K index......................... +25.5

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  -65.1 -85.2   250   38   20   1.6   0.9      M     M       M      M    M
 45000  -61.1 -78.0   255   47   24   4.5   2.5      M     M       M      M    M
 40000  -53.8 -64.8   260   47   24   7.6   4.2      M     M       M      M    M
 38000  -49.2 -56.6   255   42   22   7.7   4.2      M     M       M      M    M
 36000  -44.6 -48.3   250   37   19   7.7   4.2      M     M       M      M    M
 34000  -39.8 -39.6   255   35   18   7.9   4.3      M     M       M      M    M
 32000  -35.1 -31.2   255   34   18   7.8   4.3      M     M       M      M    M
 30000  -29.7 -21.5   260   32   17   8.0   4.4   40.0 104.0     8.6      M    M
 29000  -27.3 -17.1   260   32   16   8.0   4.4   39.4 102.9     8.2      M    M
 28000  -25.0 -13.0   265   31   16   7.4   4.1   38.8 101.8     7.8      M    M
 27000  -22.7  -8.9   260   30   15   7.4   4.1   37.8 100.0     7.1      M    M
 26000  -20.5  -4.9   260   28   15   7.4   4.1   36.9  98.4     6.5      M    M
 25000  -18.3  -0.9   255   27   14   7.1   3.9   36.2  97.1     5.9      M    M
 24000  -16.4   2.5   255   25   13   6.4   3.5   34.9  94.8     4.9      M    M
 23000  -14.5   5.9   255   22   11   6.5   3.6   33.7  92.7     3.9      M    M
 22000  -12.7   9.1   250   19   10   6.4   3.5   32.7  90.8     2.9      M    M
 21000  -10.9  12.4   250   16    8   6.1   3.4   31.3  88.4     1.7      M    M
 20000   -9.2  15.4   250   13    7   6.2   3.4   30.1  86.2     0.6      M    M
 19500   -8.3  17.1   250   12    6   6.1   3.4   29.5  85.1     0.0      M    M
 19000   -7.3  18.9   255   11    6   7.4   4.1   29.0  84.3    -0.4   1175  6.0
 18500   -6.2  20.8   260   11    6   7.3   4.0   28.6  83.5    -0.8   1128  5.7
 18000   -5.2  22.6   265   11    6   7.5   4.1   28.2  82.8    -1.2   1081  5.5
 17500   -4.0  24.8   270   11    6   7.7   4.2   27.9  82.1    -1.5   1031  5.2
 17000   -2.8  27.0   275   11    6   7.7   4.2   27.5  81.5    -1.9    982  5.0
 16500   -1.7  28.9   275   10    5   7.9   4.3   27.2  81.0    -2.2    932  4.7
 16000   -0.5  31.1   280   10    5   7.9   4.3   26.9  80.4    -2.5    882  4.5
 15500    0.7  33.3   280    9    5   8.2   4.5   26.6  79.9    -2.8    832  4.2
 15000    2.5  36.5   280    9    5   8.4   4.6   26.3  79.3    -3.1    755  3.8
 14500    3.7  38.7   275    9    5   7.5   4.1   26.0  78.8    -3.4    705  3.6
 14000    4.8  40.6   275   10    5   7.5   4.1   25.6  78.1    -3.8    657  3.3
 13500    5.9  42.6   275   11    6   8.1   4.5   25.3  77.5    -4.2    609  3.1
 13000    7.1  44.8   270   11    6   8.5   4.6   25.1  77.1    -4.5    559  2.8
 12500    8.2  46.8   265   11    6   9.4   5.1   24.9  76.8    -4.8    509  2.6
 12000    9.6  49.3   265   11    6   8.9   4.9   24.8  76.7    -4.9    454  2.3
 11750   10.2  50.4   260   11    6   8.8   4.8   24.8  76.6    -5.0    427  2.2
 11500   10.9  51.6   260   11    6  10.0   5.5   24.7  76.5    -5.1    400  2.0
 11250   11.7  53.1   260   11    6   9.9   5.4   24.8  76.6    -5.1    369  1.9
 11000   12.3  54.1   265   11    6   8.4   4.6   24.7  76.5    -5.2    343  1.7
 10750   12.9  55.2   265   11    6   8.6   4.7   24.6  76.3    -5.3    316  1.6
 10500   13.6  56.5   265   11    6   8.8   4.8   24.5  76.2    -5.4    290  1.5
 10250   14.2  57.6   270   11    6   9.1   5.0   24.5  76.1    -5.5    262  1.3
 10000   14.9  58.8   270   11    5   9.1   5.0   24.4  76.0    -5.5    235  1.2
  9750   15.6  60.1   275   10    5   9.2   5.1   24.4  75.9    -5.6    207  1.1
  9500   16.3  61.3   280   10    5   8.6   4.7   24.3  75.8    -5.7    180  0.9
  9250   16.9  62.4   285   10    5   7.8   4.3   24.2  75.6    -5.8    155  0.8
  9000   17.4  63.3   285   10    5   7.6   4.2   24.0  75.3    -6.0    130  0.7
  8750   18.0  64.4   290   11    6   8.3   4.6   23.9  75.0    -6.2    105  0.5
  8500   18.6  65.5   290   11    6   5.1   2.8   23.7  74.7    -6.4     81  0.4
  8250   18.7  65.7   290   12    6   1.4   0.8   23.2  73.7    -6.9     69  0.4
  8000   18.9  66.0   290   13    7   2.8   1.5   22.6  72.7    -7.6     57  0.3
  7750   19.0  66.2   290   13    7   0.2   0.1   22.0  71.6    -8.2     46  0.2
  7500   18.5  65.3   285   14    7 -14.4  -7.9   20.9  69.7    -9.3     54  0.3
  7250   16.8  62.2   285   12    6 -24.4 -13.4   19.0  66.1   -11.4     97  0.5
  7000   15.1  59.2   285   10    5 -17.0  -9.3   17.0  62.6   -13.4    139  0.7
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/02/2015 at 0900 MDT          |       09/02/2015 at 1200 MDT
                                           |
K index... +21.8  LI... +271.9             | K index... +20.1  LI... +272.1
CAPE... +24.2  CIN... -90.1                | CAPE... +30.4  CIN... -33.6
                                           |
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 -65.1 -85.2  250  38 20   1.4   0.8 | -64.9 -84.8  245  35 18   0.9   0.5
 45000 -61.5 -78.7  255  47 24   4.3   2.4 | -61.5 -78.7  255  44 22   4.8   2.6
 40000 -54.3 -65.7  255  45 23   8.3   4.5 | -53.7 -64.7  250  44 23   7.7   4.2
 38000 -49.3 -56.7  255  44 23   8.3   4.6 | -49.1 -56.4  255  43 22   7.7   4.2
 36000 -44.3 -47.7  255  44 22   8.4   4.6 | -44.5 -48.1  260  43 22   7.7   4.2
 34000 -39.7 -39.5  255  39 20   7.6   4.2 | -39.5 -39.1  260  38 20   8.2   4.5
 32000 -35.1 -31.2  255  34 18   7.4   4.1 | -34.0 -29.2  255  33 17   8.7   4.8
 30000 -29.7 -21.5  255  32 16   8.0   4.4 | -29.5 -21.1  255  31 16   7.4   4.0
 29000 -27.3 -17.1  255  31 16   8.0   4.4 | -27.3 -17.1  255  30 15   7.4   4.1
 28000 -25.0 -13.0  255  30 15   7.5   4.1 | -25.1 -13.2  250  29 15   8.1   4.4
 27000 -22.7  -8.9  260  29 15   7.5   4.1 | -22.7  -8.9  255  28 15   8.0   4.4
 26000 -20.5  -4.9  260  28 15   7.5   4.1 | -20.3  -4.5  255  27 14   8.0   4.4
 25000 -18.2  -0.8  260  28 14   7.2   3.9 | -17.9  -0.2  255  27 14   7.6   4.2
 24000 -16.3   2.7  260  25 13   6.4   3.5 | -15.8   3.6  255  25 13   6.8   3.7
 23000 -14.4   6.1  260  23 12   6.4   3.5 | -13.7   7.3  255  24 12   6.8   3.7
 22000 -12.5   9.5  260  20 10   6.0   3.3 | -11.6  11.1  255  22 11   6.0   3.3
 21000 -10.9  12.4  255  17  9   5.4   3.0 | -10.2  13.6  255  20 10   5.0   2.7
 20000  -9.4  15.1  250  14  7   5.5   3.0 |  -8.8  16.2  255  18  9   5.1   2.8
 19500  -8.6  16.5  245  12  6   5.4   3.0 |  -8.1  17.4  250  17  9   5.0   2.8
 19000  -7.7  18.1  240  11  6   7.0   3.8 |  -7.2  19.0  250  17  9   6.7   3.7
 18500  -6.7  19.9  240  10  5   6.9   3.8 |  -6.3  20.7  250  16  8   6.6   3.6
 18000  -5.8  21.6  240   9  5   7.5   4.1 |  -5.3  22.5  245  15  8   6.9   3.8
 17500  -4.6  23.7  240   9  5   8.2   4.5 |  -4.2  24.4  245  15  7   7.3   4.0
 17000  -3.3  26.1  250   8  4   8.2   4.5 |  -3.2  26.2  245  14  7   7.3   4.0
 16500  -2.1  28.2  250   8  4   8.6   4.7 |  -2.0  28.4  245  13  7   8.1   4.4
 16000  -0.8  30.6  255   8  4   8.6   4.7 |  -0.9  30.4  245  13  7   8.0   4.4
 15500   0.5  32.9  260   8  4   8.3   4.5 |   0.9  33.6  250  12  6   8.0   4.4
 15000   2.3  36.1  260   8  4   8.2   4.5 |   2.1  35.8  250  11  6   8.1   4.4
 14500   3.5  38.3  265   8  4   8.2   4.5 |   3.2  37.8  255  10  5   7.4   4.1
 14000   4.7  40.5  270   8  4   8.2   4.5 |   4.3  39.7  260   8  4   7.4   4.1
 13500   5.9  42.6  275   8  4   8.2   4.5 |   5.3  41.5  265   7  4   8.1   4.4
 13000   7.1  44.8  275   8  4   8.2   4.5 |   6.5  43.7  275   6  3   8.5   4.7
 12500   8.3  46.9  280   7  4   8.6   4.7 |   7.6  45.7  295   5  2   8.2   4.5
 12000   9.5  49.1  285   7  4   8.4   4.6 |   8.9  48.0  325   4  2   9.7   5.3
 11750  10.1  50.2  285   7  4   8.1   4.5 |   9.6  49.3  335   4  2   9.6   5.3
 11500  10.7  51.3  290   7  3   9.3   5.1 |  10.3  50.5  345   4  2  10.0   5.5
 11250  11.4  52.5  295   7  3   8.8   4.8 |  11.0  51.8  350   4  2   9.8   5.4
 11000  12.0  53.6  300   6  3   7.2   3.9 |  11.7  53.1  350   4  2   9.3   5.1
 10750  12.5  54.5  305   6  3   7.3   4.0 |  12.4  54.3  350   4  2   9.3   5.1
 10500  13.1  55.6  315   6  3   8.0   4.4 |  13.1  55.6  350   4  2   9.7   5.3
 10250  13.7  56.7  320   7  3   9.2   5.1 |  13.9  57.0  355   4  2  10.3   5.6
 10000  14.3  57.7  325   7  4   8.4   4.6 |  14.6  58.3  355   4  2   9.8   5.4
  9750  14.9  58.8  330   8  4   7.8   4.3 |  15.4  59.7  355   4  2   9.5   5.2
  9500  15.5  59.9  335   8  4   7.6   4.2 |  16.1  61.0  355   4  2   9.6   5.3
  9250  16.0  60.8  340   8  4   7.0   3.8 |  16.8  62.2  355   4  2   9.5   5.2
  9000  16.6  61.9  340   9  5   7.3   4.0 |  17.5  63.5  360   4  2   9.8   5.4
  8750  17.1  62.8  345  10  5   8.9   4.9 |  18.3  64.9  360   4  2  10.8   5.9
  8500  17.8  64.0  345  10  5   7.8   4.3 |  19.1  66.4  360   4  2  10.8   5.9
  8250  18.2  64.8  340  11  6   6.0   3.3 |  19.9  67.8  360   4  2  10.5   5.7
  8000  18.6  65.5  335  11  6   6.3   3.5 |  20.6  69.1  360   4  2  10.2   5.6
  7750  19.1  66.4  330  12  6   7.0   3.9 |  21.4  70.5  005   4  2  11.6   6.4
  7500  19.5  67.1  325  11  6   6.1   3.4 |  22.3  72.1  005   4  2  12.2   6.7
  7250  19.8  67.6  320  10  5   4.3   2.4 |  23.2  73.8  005   4  2  10.9   6.0
  7000  20.0  68.0  320   9  4   5.9   3.2 |  24.0  75.2  005   5  2  12.1   6.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/02/2015 at 1500 MDT          |       09/02/2015 at 1800 MDT
                                           |
K index... +27.4  LI... +272.1             | K index... +29.5  LI... +272.2
CAPE... +44.4  CIN... -17.0                | CAPE... +43.4  CIN... -15.6
                                           |
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 -65.8 -86.4  245  35 18   1.9   1.1 | -65.8 -86.4  240  35 18   1.1   0.6
 45000 -61.6 -78.9  250  40 20   4.3   2.4 | -62.5 -80.5  245  40 21   4.3   2.4
 40000 -54.3 -65.7  255  43 22   8.4   4.6 | -55.1 -67.2  260  46 24   8.9   4.9
 38000 -49.3 -56.7  255  40 21   8.4   4.6 | -49.7 -57.5  260  40 20   8.9   4.9
 36000 -44.2 -47.6  255  38 19   8.4   4.6 | -44.3 -47.7  255  34 18   8.9   4.9
 34000 -39.2 -38.6  250  34 18   8.3   4.6 | -39.0 -38.2  250  30 15   8.8   4.8
 32000 -33.6 -28.5  250  31 16   8.9   4.9 | -33.8 -28.8  250  26 13   8.6   4.7
 30000 -28.8 -19.8  250  28 15   8.0   4.4 | -28.3 -18.9  250  23 12   8.0   4.4
 29000 -26.4 -15.5  250  27 14   8.0   4.4 | -26.0 -14.8  250  21 11   8.1   4.4
 28000 -24.1 -11.4  250  26 13   7.4   4.0 | -23.6 -10.5  250  20 10   6.8   3.7
 27000 -21.9  -7.4  250  25 13   7.4   4.1 | -21.6  -6.9  250  20 10   6.9   3.8
 26000 -19.7  -3.5  250  23 12   7.4   4.1 | -19.6  -3.3  250  20 10   6.9   3.8
 25000 -17.5   0.5  250  22 11   7.3   4.0 | -17.5   0.5  245  19 10   6.9   3.8
 24000 -15.3   4.5  250  22 11   7.1   3.9 | -15.6   3.9  250  18  9   6.7   3.7
 23000 -13.2   8.2  250  22 11   7.1   3.9 | -13.6   7.5  260  17  9   6.7   3.7
 22000 -11.1  12.0  255  21 11   6.3   3.4 | -11.7  10.9  265  17  9   6.6   3.6
 21000  -9.5  14.9  260  22 11   5.2   2.8 |  -9.8  14.4  265  14  7   6.4   3.5
 20000  -8.0  17.6  265  22 11   5.2   2.8 |  -7.9  17.8  265  12  6   6.5   3.5
 19500  -7.2  19.0  265  22 11   5.1   2.8 |  -7.0  19.4  265  11  6   6.5   3.6
 19000  -6.4  20.5  270  22 11   6.5   3.5 |  -6.1  21.0  260  10  5   6.0   3.3
 18500  -5.5  22.1  270  21 11   6.5   3.5 |  -5.3  22.5  255   8  4   6.1   3.3
 18000  -4.7  23.5  270  20 10   6.9   3.8 |  -4.4  24.1  250   7  4   6.4   3.5
 17500  -3.7  25.3  270  18  9   7.3   4.0 |  -3.4  25.9  235   6  3   6.7   3.7
 17000  -2.6  27.3  270  16  8   7.5   4.1 |  -2.4  27.7  210   5  2   6.7   3.7
 16500  -1.6  29.1  270  14  7   7.0   3.9 |  -1.4  29.5  190   4  2   7.1   3.9
 16000  -0.6  30.9  270  11  6   7.1   3.9 |  -0.4  31.3  170   5  2   7.1   3.9
 15500   0.9  33.6  275   6  3   7.7   4.2 |   0.6  33.1  155   5  3   8.2   4.5
 15000   2.1  35.8  275   3  2   7.5   4.1 |   2.6  36.7  145   5  3   8.7   4.8
 14500   3.2  37.8  000   0  0   9.0   4.9 |   3.9  39.0  140   5  3   9.1   5.0
 14000   4.6  40.3  090   1  0   9.1   5.0 |   5.2  41.4  140   5  3   9.1   5.0
 13500   5.9  42.6  095   2  1   9.2   5.1 |   6.6  43.9  140   6  3   9.3   5.1
 13000   7.3  45.1  100   2  1   9.4   5.1 |   8.0  46.4  140   6  3   9.5   5.2
 12500   8.6  47.5  100   2  1   9.1   5.0 |   9.4  48.9  140   6  3   8.5   4.6
 12000  10.1  50.2  105   2  1   9.5   5.2 |  10.7  51.3  140   6  3   9.1   5.0
 11750  10.8  51.4  105   2  1   9.7   5.3 |  11.4  52.5  140   6  3   9.0   4.9
 11500  11.5  52.7  110   3  1   9.2   5.1 |  12.0  53.6  140   6  3   9.2   5.0
 11250  12.2  54.0  110   3  1   9.5   5.2 |  12.7  54.9  145   6  3   8.9   4.9
 11000  12.9  55.2  115   3  1  10.0   5.5 |  13.4  56.1  145   6  3   8.4   4.6
 10750  13.6  56.5  115   3  1  10.0   5.5 |  14.0  57.2  145   6  3   8.6   4.7
 10500  14.4  57.9  115   3  2   9.6   5.3 |  14.6  58.3  150   6  3   8.4   4.6
 10250  15.1  59.2  115   3  2   9.0   5.0 |  15.2  59.4  150   6  3   8.0   4.4
 10000  15.8  60.4  120   3  2  10.1   5.5 |  15.9  60.6  155   5  3   8.9   4.9
  9750  16.6  61.9  120   3  2  11.1   6.1 |  16.5  61.7  160   6  3   9.8   5.4
  9500  17.4  63.3  120   3  2  10.2   5.6 |  17.2  63.0  165   6  3   9.1   5.0
  9250  18.1  64.6  120   3  2   9.1   5.0 |  17.8  64.0  170   6  3   8.0   4.4
  9000  18.7  65.7  120   3  2   9.5   5.2 |  18.4  65.1  175   6  3   8.4   4.6
  8750  19.5  67.1  120   3  2  10.8   5.9 |  19.1  66.4  175   6  3  10.7   5.9
  8500  20.3  68.5  125   3  2  10.8   5.9 |  20.0  68.0  180   6  3  10.5   5.8
  8250  21.1  70.0  125   3  2  10.1   5.6 |  20.7  69.3  180   6  3   9.2   5.0
  8000  21.9  71.4  125   3  2  10.0   5.5 |  21.3  70.3  180   6  3   8.8   4.8
  7750  22.6  72.7  125   4  2  10.8   5.9 |  22.0  71.6  185   6  3  10.4   5.7
  7500  23.5  74.3  125   4  2  11.9   6.5 |  22.8  73.0  185   7  3   8.9   4.9
  7250  24.3  75.7  125   4  2  11.9   6.5 |  23.2  73.8  185   6  3   5.5   3.0
  7000  25.2  77.4  120   4  2  12.0   6.6 |  23.7  74.7  180   6  3   8.2   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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