Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 241028
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0428 MDT Wednesday, September 24, 2014

This forecast is for Wednesday, September 24, 2014:

If the trigger temperature of 66.0 F/18.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 836 ft/min (4.2 m/s)
   Maximum height of thermals.................. 16675 ft MSL (9505 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1015 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................. 14092 ft MSL (6922 ft AGL)
Thermal soaring outlook for Thursday 09/25..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 17521 ft MSL (10351 ft AGL)
Wave soaring outlook for Thursday 09/25........ Poor

Remarks...

Sunrise/Sunset.................... 06:48:32 / 18:54:17 MDT
Total possible sunshine........... 12 hr 5 min 45 sec (725 min 45 sec)
Altitude of sun at 12:50:55 MDT... 50.40 degrees

Upper air data from numerical model forecast valid on 09/24/2014 at 0600 MDT

Freezing level.................. 14363 ft MSL (7193 ft AGL)
Convective condensation level... 15331 ft MSL (8161 ft AGL)
Lifted condensation level....... 16102 ft MSL (8932 ft AGL)
Lifted index.................... -2.0
K index......................... +14.5

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  -64.8 -84.6   330   16    8   2.5   1.4      M     M       M      M    M
 45000  -59.2 -74.6   330   30   16   6.2   3.4      M     M       M      M    M
 40000  -50.2 -58.4   345   35   18   3.6   2.0      M     M       M      M    M
 38000  -48.1 -54.6   360   43   22   3.5   1.9      M     M       M      M    M
 36000  -46.0 -50.8   010   53   27   3.4   1.8      M     M       M      M    M
 34000  -42.1 -43.8   010   53   27   7.2   3.9      M     M       M      M    M
 32000  -37.8 -36.0   015   50   26   7.2   4.0      M     M       M      M    M
 30000  -33.4 -28.1   010   41   21   7.5   4.1   36.9  98.3     9.6      M    M
 29000  -31.2 -24.2   005   36   19   7.5   4.1   36.0  96.8     9.0      M    M
 28000  -28.9 -20.0   355   31   16   7.6   4.2   35.3  95.5     8.6      M    M
 27000  -26.0 -14.8   355   29   15   7.8   4.3   34.2  93.6     7.8      M    M
 26000  -23.7 -10.7   350   28   14   7.8   4.3   33.5  92.4     7.4      M    M
 25000  -21.3  -6.3   350   26   13   7.8   4.3   33.0  91.3     6.9      M    M
 24000  -19.0  -2.2   350   25   13   7.6   4.2   32.1  89.8     6.3      M    M
 23000  -16.7   1.9   355   24   12   7.6   4.2   31.3  88.4     5.7      M    M
 22000  -14.5   5.9   355   23   12   7.4   4.1   30.7  87.3     5.2      M    M
 21000  -12.3   9.9   355   21   11   7.1   3.9   29.7  85.5     4.4      M    M
 20000  -10.2  13.6   360   19   10   7.1   3.9   28.8  83.9     3.7      M    M
 19500   -9.1  15.6   360   18    9   7.2   3.9   28.4  83.1     3.4      M    M
 19000   -8.2  17.2   360   18    9   5.7   3.1   27.8  82.1     2.9      M    M
 18500   -7.3  18.9   360   17    9   5.8   3.2   27.2  80.9     2.3      M    M
 18000   -6.5  20.3   360   17    9   5.8   3.2   26.5  79.8     1.7      M    M
 17500   -5.6  21.9   355   16    8   5.7   3.1   25.8  78.5     1.0      M    M
 17000   -4.8  23.4   350   16    8   5.8   3.2   25.2  77.3     0.4      M    M
 16500   -3.9  25.0   340   15    8   6.5   3.6   24.6  76.2    -0.2    825  4.2
 16000   -3.0  26.6   335   15    8   6.6   3.6   24.0  75.2    -0.7    783  4.0
 15500   -2.1  28.2   325   15    8   6.3   3.5   23.5  74.3    -1.3    741  3.8
 15000   -1.3  29.7   325   15    8   6.4   3.5   22.9  73.2    -2.0    702  3.6
 14500   -0.4  31.3   320   15    8   7.1   3.9   22.4  72.3    -2.6    661  3.4
 14000    0.6  33.1   325   15    8   7.6   4.2   22.0  71.7    -3.0    615  3.1
 13500    1.7  35.1   325   15    8   7.7   4.2   21.7  71.1    -3.4    568  2.9
 13000    2.8  37.0   330   15    8   7.6   4.2   21.4  70.5    -3.8    520  2.6
 12500    3.9  39.0   330   14    7   7.3   4.0   21.0  69.9    -4.2    472  2.4
 12000    4.9  40.8   335   12    6   7.3   4.0   20.6  69.1    -4.7    427  2.2
 11750    5.4  41.7   335   11    6   7.3   4.0   20.4  68.8    -4.9    404  2.1
 11500    6.0  42.8   335   10    5   7.5   4.1   20.2  68.4    -5.1    381  1.9
 11250    6.5  43.7   340    9    5   8.6   4.7   20.1  68.2    -5.3    356  1.8
 11000    7.2  45.0   340    7    4   8.6   4.7   20.0  68.1    -5.3    329  1.7
 10750    7.8  46.0   345    6    3   7.8   4.3   19.9  67.8    -5.5    304  1.5
 10500    8.4  47.1   355    5    2   8.1   4.4   19.8  67.6    -5.6    278  1.4
 10250    9.7  49.5   015    4    2   9.0   4.9   19.6  67.3    -5.8    225  1.1
 10000   10.3  50.5   030    4    2   8.0   4.4   19.5  67.1    -5.9    197  1.0
  9750   10.9  51.6   040    4    2   8.0   4.4   19.4  66.8    -6.1    172  0.9
  9500   11.6  52.9   045    4    2   9.2   5.1   19.3  66.7    -6.1    145  0.7
  9250   12.3  54.1   055    4    2   9.9   5.4   19.3  66.7    -6.2    116  0.6
  9000   13.1  55.6   060    4    2   8.8   4.8   19.2  66.6    -6.2     86  0.4
  8750   13.7  56.7   065    4    2   7.2   3.9   19.1  66.4    -6.3     61  0.3
  8500   14.2  57.6   065    4    2   7.3   4.0   18.9  66.0    -6.5     37  0.2
  8250   14.8  58.6   060    3    2   6.8   3.7   18.7  65.7    -6.7     13  0.1
  8000   15.3  59.5   055    3    1   9.2   5.0   18.5  65.3    -6.9      M    M
  7750   15.7  60.3   045    2    1  -5.9  -3.2   18.2  64.7    -7.2      M    M
  7500   14.0  57.2   320    3    1 -37.6 -20.6   15.8  60.4    -9.7     15  0.1
  7250   12.2  54.0   295    6    3  20.7  11.4   13.3  56.0   -12.2     59  0.3
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/24/2014 at 0900 MDT          |       09/24/2014 at 1200 MDT
                                           |
K index... +14.9  LI... +0.6               | K index... +15.0  LI... +0.4
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.8 -84.6  330  15  8   2.8   1.5 | -64.8 -84.6  330  15  8   2.9   1.6
 45000 -59.1 -74.4  340  28 14   6.1   3.3 | -59.3 -74.7  345  26 13   5.3   2.9
 40000 -50.3 -58.5  350  36 19   3.5   1.9 | -51.4 -60.5  360  38 20   4.7   2.6
 38000 -48.2 -54.8  005  43 22   3.6   1.9 | -48.6 -55.5  010  42 21   4.7   2.6
 36000 -45.8 -50.4  020  53 27   3.5   1.9 | -45.4 -49.7  020  47 24   5.0   2.8
 34000 -41.5 -42.7  020  52 27   7.6   4.2 | -41.1 -42.0  020  45 23   7.4   4.1
 32000 -36.9 -34.4  015  49 25   7.6   4.2 | -36.7 -34.1  015  42 22   7.3   4.0
 30000 -32.3 -26.1  010  44 23   7.7   4.2 | -31.9 -25.4  010  41 21   8.2   4.5
 29000 -30.0 -22.0  005  42 22   7.7   4.2 | -29.4 -20.9  005  40 21   8.2   4.5
 28000 -27.7 -17.9  360  40 21   7.6   4.2 | -27.0 -16.6  005  40 20   7.7   4.2
 27000 -25.4 -13.7  360  37 19   7.5   4.1 | -24.8 -12.6  005  37 19   7.4   4.1
 26000 -23.2  -9.8  360  35 18   7.5   4.1 | -22.6  -8.7  010  35 18   7.4   4.1
 25000 -21.0  -5.8  360  32 17   7.5   4.1 | -20.4  -4.7  010  32 17   7.4   4.1
 24000 -18.9  -2.0  360  29 15   7.1   3.9 | -18.4  -1.1  010  28 15   6.6   3.6
 23000 -16.2   2.8  360  24 12   7.1   3.9 | -15.9   3.4  010  23 12   6.7   3.7
 22000 -14.1   6.6  360  20 10   6.9   3.8 | -13.9   7.0  005  19 10   7.0   3.8
 21000 -12.1  10.2  360  17  9   6.8   3.7 | -11.8  10.8  005  16  8   7.1   3.9
 20000 -10.1  13.8  360  15  8   6.8   3.7 |  -9.7  14.5  360  13  7   7.1   3.9
 19500  -9.0  15.8  360  14  7   6.8   3.7 |  -8.7  16.3  355  12  6   6.9   3.8
 19000  -8.1  17.4  360  13  7   6.4   3.5 |  -7.7  18.1  355  11  6   6.4   3.5
 18500  -7.1  19.2  360  13  7   6.4   3.5 |  -6.7  19.9  355  10  5   6.5   3.6
 18000  -6.2  20.8  360  12  6   5.8   3.2 |  -5.8  21.6  355   9  5   5.9   3.3
 17500  -5.4  22.3  360  13  7   5.7   3.1 |  -5.0  23.0  355   9  5   5.9   3.2
 17000  -4.6  23.7  360  13  7   5.8   3.2 |  -4.1  24.6  350  10  5   5.9   3.2
 16500  -3.7  25.3  355  13  7   6.1   3.4 |  -3.3  26.1  350   9  5   5.9   3.2
 16000  -2.8  27.0  355  13  6   6.1   3.3 |  -2.4  27.7  350   9  4   5.8   3.2
 15500  -1.9  28.6  350  12  6   6.9   3.8 |  -1.5  29.3  345   8  4   6.7   3.7
 15000  -0.9  30.4  340  11  6   6.9   3.8 |  -0.6  30.9  340   7  4   6.7   3.7
 14500   0.1  32.2  335  11  5   7.2   3.9 |   0.4  32.7  340   7  4   7.2   4.0
 14000   1.0  33.8  325  10  5   7.4   4.0 |   1.4  34.5  330   7  3   7.4   4.1
 13500   2.0  35.6  320  10  5   7.6   4.2 |   2.4  36.3  320   7  3   7.7   4.2
 13000   3.1  37.6  320  10  5   7.7   4.2 |   3.5  38.3  315   6  3   7.8   4.3
 12500   4.2  39.6  325   9  5   6.9   3.8 |   4.6  40.3  305   6  3   7.1   3.9
 12000   5.2  41.4  325   8  4   8.5   4.7 |   5.7  42.3  300   5  3   9.2   5.0
 11750   5.8  42.4  325   7  4   8.4   4.6 |   6.3  43.3  295   4  2   8.9   4.9
 11500   6.4  43.5  325   7  3   8.2   4.5 |   7.0  44.6  285   4  2   8.7   4.8
 11250   7.0  44.6  320   6  3   7.4   4.0 |   7.6  45.7  270   3  2   8.0   4.4
 11000   7.5  45.5  310   5  2   7.3   4.0 |   8.2  46.8  250   4  2   8.6   4.7
 10750   8.1  46.6  290   4  2   7.6   4.1 |   8.9  48.0  235   4  2   9.3   5.1
 10500   8.6  47.5  270   4  2   7.6   4.1 |   9.5  49.1  220   4  2   9.0   5.0
 10250   9.2  48.6  255   4  2   7.7   4.2 |  10.2  50.4  210   5  2   8.9   4.9
 10000   9.8  49.6  240   4  2   7.7   4.2 |  10.9  51.6  205   5  3   8.9   4.9
  9750  10.3  50.5  225   4  2   6.9   3.8 |  11.5  52.7  200   6  3   8.8   4.8
  9500  11.4  52.5  195   4  2   8.5   4.6 |  12.9  55.2  195   6  3  10.1   5.5
  9250  12.1  53.8  190   4  2   9.1   5.0 |  13.7  56.7  195   6  3  10.4   5.7
  9000  12.8  55.0  185   5  2   7.3   4.0 |  14.4  57.9  190   6  3   9.4   5.2
  8750  13.2  55.8  180   5  3   7.0   3.8 |  15.1  59.2  190   6  3   9.6   5.2
  8500  13.9  57.0  180   5  3   9.0   4.9 |  15.9  60.6  190   7  3  10.9   6.0
  8250  14.5  58.1  175   5  2   8.7   4.8 |  16.7  62.1  190   7  3  10.6   5.8
  8000  15.2  59.4  170   4  2   9.3   5.1 |  17.5  63.5  185   7  3  11.0   6.0
  7750  15.9  60.6  165   4  2  11.4   6.2 |  18.4  65.1  185   7  3  16.6   9.1
  7500  16.8  62.2  170   2  1  13.2   7.2 |  20.0  68.0  185   7  3  24.7  13.6
  7250  17.7  63.9  195   1  0  10.6   5.8 |  21.5  70.7  185   6  3  10.6   5.8
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/24/2014 at 1500 MDT          |       09/24/2014 at 1800 MDT
                                           |
K index... +19.8  LI... -0.3               | K index... +21.7  LI... -0.6
CAPE... +34.0  CIN... -7.5                 | CAPE... +20.0  CIN... -20.8
                                           |
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 -65.4 -85.7  340  17  9   2.9   1.6 | -65.4 -85.7  340  19 10   2.6   1.4
 45000 -60.0 -76.0  350  27 14   5.2   2.9 | -60.2 -76.4  350  29 15   5.3   2.9
 40000 -52.2 -62.0  005  35 18   5.4   3.0 | -52.2 -62.0  010  33 17   5.5   3.0
 38000 -48.9 -56.0  020  39 20   5.4   3.0 | -49.0 -56.2  030  37 19   5.5   3.0
 36000 -45.2 -49.4  025  44 23   5.9   3.2 | -45.3 -49.5  045  45 23   6.2   3.4
 34000 -40.8 -41.4  025  42 21   7.5   4.1 | -40.5 -40.9  040  42 22   8.0   4.4
 32000 -36.3 -33.3  020  39 20   7.4   4.1 | -35.7 -32.3  035  40 20   8.2   4.5
 30000 -31.5 -24.7  020  38 20   8.1   4.5 | -31.2 -24.2  030  38 20   7.5   4.1
 29000 -29.1 -20.4  015  38 20   8.1   4.5 | -28.9 -20.0  025  37 19   7.5   4.1
 28000 -26.6 -15.9  015  38 19   7.8   4.3 | -26.7 -16.1  025  37 19   8.2   4.5
 27000 -24.4 -11.9  015  37 19   7.7   4.2 | -24.2 -11.6  025  36 18   8.3   4.6
 26000 -22.1  -7.8  020  35 18   7.7   4.2 | -21.7  -7.1  025  35 18   8.3   4.6
 25000 -19.8  -3.6  020  34 17   7.6   4.2 | -19.2  -2.6  025  34 17   8.2   4.5
 24000 -17.7   0.1  020  30 15   6.8   3.7 | -17.1   1.2  025  30 16   7.1   3.9
 23000 -15.2   4.6  015  24 12   6.8   3.7 | -14.4   6.1  020  26 13   7.2   3.9
 22000 -13.2   8.2  010  19 10   6.7   3.7 | -12.4   9.7  020  22 12   5.8   3.2
 21000 -11.2  11.8  005  17  9   6.7   3.7 | -10.7  12.7  005  21 11   5.6   3.1
 20000  -9.3  15.3  355  15  8   6.8   3.7 |  -9.1  15.6  355  19 10   5.7   3.1
 19500  -8.3  17.1  350  14  7   6.6   3.6 |  -8.3  17.1  345  19 10   5.9   3.2
 19000  -7.4  18.7  345  13  7   6.0   3.3 |  -7.4  18.7  345  20 10   6.3   3.4
 18500  -6.5  20.3  340  13  7   6.0   3.3 |  -6.5  20.3  340  20 11   6.2   3.4
 18000  -5.6  21.9  335  13  7   6.0   3.3 |  -5.6  21.9  335  21 11   7.3   4.0
 17500  -4.7  23.5  325  13  6   6.1   3.3 |  -4.5  23.9  335  20 10   7.5   4.1
 17000  -3.9  25.0  320  13  6   6.3   3.5 |  -3.4  25.9  335  20 10   7.3   4.0
 16500  -2.9  26.8  315  12  6   6.9   3.8 |  -2.4  27.7  335  18  9   7.0   3.8
 16000  -1.9  28.6  310  12  6   6.8   3.8 |  -1.4  29.5  335  16  8   7.0   3.8
 15500  -0.9  30.4  310  12  6   7.7   4.2 |  -0.4  31.3  335  13  7   7.2   3.9
 15000   0.1  32.2  305  10  5   7.8   4.3 |   0.6  33.1  340  10  5   7.3   4.0
 14500   1.2  34.2  305   9  5   7.7   4.2 |   1.6  34.9  345   7  3   7.6   4.2
 14000   2.3  36.1  305   7  4   7.7   4.2 |   2.7  36.9  005   5  2   7.8   4.3
 13500   3.3  37.9  310   5  3   8.1   4.5 |   3.8  38.8  045   4  2   8.2   4.5
 13000   4.6  40.3  310   3  2   8.4   4.6 |   5.1  41.2  065   4  2   8.5   4.6
 12500   5.8  42.4  305   2  1   7.3   4.0 |   6.3  43.3  080   4  2   7.6   4.1
 12000   6.9  44.4  260   1  0   8.9   4.9 |   7.5  45.5  095   5  2   9.1   5.0
 11750   7.6  45.7  215   1  0   8.5   4.6 |   8.2  46.8  095   5  3   8.7   4.8
 11500   8.2  46.8  180   1  1   8.5   4.7 |   8.8  47.8  100   5  3   8.8   4.9
 11250   8.8  47.8  170   2  1   8.2   4.5 |   9.5  49.1  110   5  3   9.0   5.0
 11000   9.4  48.9  170   3  1   8.9   4.9 |  10.2  50.4  115   5  3   8.3   4.5
 10750  10.1  50.2  165   4  2   9.4   5.2 |  10.8  51.4  120   5  3   7.6   4.2
 10500  10.8  51.4  165   5  2   9.4   5.2 |  11.3  52.3  125   6  3   7.8   4.3
 10250  11.5  52.7  165   5  3   9.8   5.4 |  11.9  53.4  130   6  3   8.0   4.4
 10000  12.2  54.0  165   5  3   9.8   5.4 |  12.5  54.5  140   6  3   8.0   4.4
  9750  12.9  55.2  165   6  3   9.0   4.9 |  13.1  55.6  150   6  3   6.6   3.6
  9500  14.3  57.7  165   6  3  10.3   5.6 |  14.1  57.4  160   7  3   8.4   4.6
  9250  15.1  59.2  165   6  3  10.6   5.8 |  14.7  58.5  165   7  4   8.7   4.8
  9000  15.9  60.6  165   6  3   9.7   5.3 |  15.3  59.5  170   7  4   8.5   4.6
  8750  16.6  61.9  165   7  3   9.6   5.3 |  16.0  60.8  170   8  4   9.1   5.0
  8500  17.3  63.1  165   7  3  10.6   5.8 |  16.7  62.1  170   8  4   9.9   5.4
  8250  18.1  64.6  165   7  4  10.8   5.9 |  17.4  63.3  170   8  4  10.0   5.5
  8000  18.9  66.0  165   7  4  10.0   5.5 |  18.2  64.8  175   8  4   9.7   5.3
  7750  19.8  67.6  165   7  4  15.2   8.4 |  18.9  66.0  175   8  4  10.3   5.6
  7500  21.3  70.3  165   7  4  26.1  14.3 |  19.7  67.5  170   7  4  12.2   6.7
  7250  22.8  73.0  160   7  4   6.2   3.4 |  20.5  68.9  170   7  4   8.5   4.7
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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