Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 201012
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0412 MDT Wednesday, August 20, 2014

This forecast is for Wednesday, August 20, 2014:

If the trigger temperature of 74.0 F/23.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 171 ft/min (0.9 m/s)
   Maximum height of thermals.................. 13243 ft MSL (6485 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8284 ft MSL (1527 ft AGL)
Thermal soaring outlook for Thursday 08/21..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 36279 ft MSL (29521 ft AGL)
Wave soaring outlook for Thursday 08/21........ Poor

Remarks...

Sunrise/Sunset.................... 06:17:04 / 19:48:10 MDT
Total possible sunshine........... 13 hr 31 min 7 sec (811 min 7 sec)
Altitude of sun at 13:02:14 MDT... 63.32 degrees

Upper air data from numerical model forecast valid on 08/20/2014 at 0600 MDT

Freezing level.................. 15914 ft MSL (9156 ft AGL)
Convective condensation level... 16036 ft MSL (9278 ft AGL)
Lifted condensation level....... 15193 ft MSL (8435 ft AGL)
Lifted index.................... +0.1
K index......................... +23.5

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  -65.5 -85.9   265   36   19   1.1   0.6      M     M       M      M    M
 45000  -61.4 -78.5   260   51   26   5.9   3.3      M     M       M      M    M
 40000  -52.4 -62.3   250   41   21   6.6   3.6      M     M       M      M    M
 38000  -48.4 -55.1   245   41   21   6.6   3.6      M     M       M      M    M
 36000  -44.4 -47.9   245   40   21   6.4   3.5      M     M       M      M    M
 34000  -39.1 -38.4   245   37   19   9.2   5.1      M     M       M      M    M
 32000  -33.6 -28.5   245   33   17   9.1   5.0      M     M       M      M    M
 30000  -28.0 -18.4   240   31   16   8.0   4.4   41.9 107.4    13.1      M    M
 29000  -25.6 -14.1   240   30   15   8.1   4.4   41.3 106.4    12.8      M    M
 28000  -23.2  -9.8   240   29   15   7.0   3.9   40.8 105.4    12.5      M    M
 27000  -21.2  -6.2   240   29   15   6.7   3.7   39.5 103.1    11.6      M    M
 26000  -19.3  -2.7   240   28   14   6.7   3.7   38.3 101.0    10.8      M    M
 25000  -17.3   0.9   240   28   14   6.7   3.7   37.3  99.2    10.0      M    M
 24000  -15.5   4.1   240   27   14   6.1   3.4   36.0  96.8     9.0      M    M
 23000  -13.7   7.3   240   27   14   6.2   3.4   34.7  94.4     7.9      M    M
 22000  -11.9  10.6   240   26   13   6.3   3.5   33.5  92.4     6.9      M    M
 21000  -10.0  14.0   235   26   13   6.8   3.7   32.4  90.3     5.9      M    M
 20000   -8.0  17.6   225   25   13   6.8   3.8   31.4  88.5     5.1      M    M
 19500   -7.0  19.4   225   25   13   6.9   3.8   30.9  87.7     4.7      M    M
 19000   -6.0  21.2   220   25   13   5.4   3.0   30.4  86.8     4.2      M    M
 18500   -5.3  22.5   220   24   12   4.9   2.7   29.6  85.2     3.5      M    M
 18000   -4.6  23.7   215   23   12   4.9   2.7   28.8  83.8     2.7      M    M
 17500   -3.7  25.3   215   22   11   7.4   4.1   28.2  82.7     2.2      M    M
 17000   -2.7  27.1   210   21   11   7.2   4.0   27.8  82.0     1.8      M    M
 16500   -1.6  29.1   210   21   11   7.6   4.2   27.4  81.3     1.4      M    M
 16000   -0.4  31.3   205   20   10   7.8   4.3   27.0  80.7     1.1      M    M
 15500    0.7  33.3   205   18   10   8.1   4.4   26.7  80.1     0.8      M    M
 15000    2.0  35.6   205   18    9   9.0   4.9   26.6  79.8     0.6      M    M
 14500    4.0  39.2   210   17    9   8.7   4.7   26.4  79.5     0.5      M    M
 14000    5.3  41.5   215   18    9   8.4   4.6   26.1  79.0     0.3      M    M
 13500    6.5  43.7   220   18   10   8.4   4.6   25.9  78.7     0.1      M    M
 13000    7.7  45.9   225   20   10   8.3   4.6   25.7  78.3    -0.2    535  2.7
 12500    9.0  48.2   230   21   11   8.0   4.4   25.5  77.9    -0.4    484  2.5
 12000   10.1  50.2   240   22   11   7.4   4.1   25.1  77.2    -0.8    437  2.2
 11750   10.6  51.1   240   22   11   7.3   4.0   24.9  76.9    -1.0    413  2.1
 11500   11.1  52.0   245   22   11   7.8   4.3   24.8  76.6    -1.2    390  2.0
 11250   11.7  53.1   245   22   12   8.2   4.5   24.6  76.3    -1.3    365  1.9
 11000   12.3  54.1   245   21   11   7.9   4.4   24.5  76.1    -1.5    341  1.7
 10750   12.8  55.0   250   20   10   7.9   4.3   24.3  75.8    -1.7    316  1.6
 10500   13.4  56.1   250   19   10   8.3   4.6   24.2  75.6    -1.8    292  1.5
 10250   14.0  57.2   250   18    9   6.7   3.7   24.1  75.4    -2.0    268  1.4
 10000   14.4  57.9   250   17    9   7.8   4.3   23.8  74.9    -2.2    246  1.3
  9750   15.1  59.2   250   16    8  10.2   5.6   23.8  74.9    -2.3    217  1.1
  9500   15.9  60.6   250   14    7   9.9   5.5   23.8  74.9    -2.3    189  1.0
  9250   16.6  61.9   245   13    7   8.6   4.7   23.8  74.9    -2.3    160  0.8
  9000   17.1  62.8   245   12    6   7.3   4.0   23.7  74.6    -2.5    137  0.7
  8750   17.7  63.9   240   11    6   8.1   4.5   23.5  74.3    -2.7    112  0.6
  8500   18.3  64.9   240   10    5   8.6   4.7   23.4  74.1    -2.8     87  0.4
  8250   18.8  65.8   235   10    5   3.7   2.1   23.2  73.8    -3.0     65  0.3
  8000   18.7  65.7   235    9    5  -2.0  -1.1   22.5  72.4    -3.8     58  0.3
  7750   18.7  65.7   235    8    4   4.6   2.5   21.7  71.1    -4.6     52  0.3
  7500   19.1  66.4   240    8    4   3.5   1.9   21.5  70.7    -4.9     31  0.2
  7250   18.6  65.5   245    7    4 -18.1  -9.9   20.5  68.9    -6.0     40  0.2
  7000   16.4  61.5   250    6    3 -35.0 -19.2   18.2  64.7    -8.4     98  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/20/2014 at 0900 MDT          |       08/20/2014 at 1200 MDT
                                           |
K index... +24.4  LI... -1.7               | K index... +26.8  LI... -1.3
CAPE... +146.2  CIN... -65.1               | CAPE... +200.3  CIN... -2.2
                                           |
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  265  35 18   0.8   0.4 | -65.5 -85.9  255  33 17   1.0   0.5
 45000 -61.3 -78.3  260  56 29   6.1   3.3 | -61.3 -78.3  260  53 27   6.3   3.5
 40000 -52.0 -61.6  250  48 25   6.8   3.7 | -51.7 -61.1  250  48 25   7.1   3.9
 38000 -47.9 -54.2  250  45 23   6.8   3.7 | -47.4 -53.3  245  45 23   7.1   3.9
 36000 -43.8 -46.8  245  41 21   6.7   3.7 | -43.1 -45.6  240  42 22   7.0   3.8
 34000 -38.9 -38.0  240  38 20   8.4   4.6 | -38.4 -37.1  235  38 19   8.0   4.4
 32000 -33.2 -27.8  235  35 18   8.8   4.8 | -32.9 -27.2  225  33 17   8.3   4.5
 30000 -28.4 -19.1  235  33 17   8.0   4.4 | -28.2 -18.8  230  31 16   7.9   4.3
 29000 -26.0 -14.8  235  31 16   8.0   4.4 | -25.8 -14.4  230  30 15   7.9   4.3
 28000 -23.6 -10.5  235  30 15   7.3   4.0 | -23.5 -10.3  230  29 15   7.4   4.1
 27000 -21.5  -6.7  230  29 15   7.0   3.9 | -21.3  -6.3  230  30 15   7.3   4.0
 26000 -19.4  -2.9  230  29 15   7.1   3.9 | -19.2  -2.6  230  30 15   7.4   4.1
 25000 -17.3   0.9  230  28 15   7.2   4.0 | -17.0   1.4  230  30 16   7.6   4.2
 24000 -15.6   3.9  230  28 14   5.9   3.2 | -15.0   5.0  230  30 15   6.9   3.8
 23000 -13.9   7.0  230  27 14   5.9   3.3 | -13.0   8.6  235  28 15   6.9   3.8
 22000 -12.2  10.0  230  26 13   6.0   3.3 | -10.9  12.4  235  27 14   6.9   3.8
 21000 -10.3  13.5  230  25 13   6.5   3.6 |  -9.1  15.6  235  26 13   6.1   3.4
 20000  -8.4  16.9  225  25 13   6.5   3.6 |  -7.3  18.9  230  25 13   6.2   3.4
 19500  -7.4  18.7  225  25 13   6.5   3.6 |  -6.4  20.5  230  24 12   6.2   3.4
 19000  -6.5  20.3  225  24 13   6.2   3.4 |  -5.5  22.1  230  23 12   5.9   3.2
 18500  -5.6  21.9  220  23 12   6.0   3.3 |  -4.7  23.5  230  23 12   5.8   3.2
 18000  -4.7  23.5  220  22 11   6.0   3.3 |  -3.9  25.0  230  22 11   5.8   3.2
 17500  -3.8  25.2  215  21 11   7.4   4.1 |  -3.0  26.6  230  21 11   6.2   3.4
 17000  -2.7  27.1  215  20 10   7.3   4.0 |  -2.1  28.2  225  21 11   6.2   3.4
 16500  -1.6  29.1  215  18  9   7.9   4.3 |  -1.2  29.8  225  20 10   6.1   3.3
 16000  -0.4  31.3  215  17  9   8.1   4.5 |  -0.3  31.5  225  19 10   6.0   3.3
 15500   1.3  34.3  215  15  8   8.2   4.5 |   1.0  33.8  225  17  9   6.4   3.5
 15000   2.5  36.5  220  14  7   8.2   4.5 |   1.9  35.4  225  16  8   6.4   3.5
 14500   3.7  38.7  220  13  7   7.9   4.3 |   2.8  37.0  225  14  7   6.5   3.5
 14000   4.8  40.6  225  11  6   7.6   4.2 |   3.7  38.7  225  12  6   6.5   3.6
 13500   5.9  42.6  235  10  5   7.5   4.1 |   4.6  40.3  230  10  5   7.2   3.9
 13000   7.0  44.6  245  10  5   7.1   3.9 |   5.8  42.4  235   8  4   9.0   4.9
 12500   8.0  46.4  255  10  5   6.4   3.5 |   7.1  44.8  250   6  3   7.7   4.2
 12000   9.0  48.2  265  11  6   7.6   4.2 |   8.3  46.9  260   5  3  10.0   5.5
 11750   9.5  49.1  270  11  6   7.2   3.9 |   9.0  48.2  265   5  3   9.7   5.3
 11500  10.1  50.2  275  12  6   7.9   4.3 |   9.7  49.5  270   5  2   9.2   5.1
 11250  10.7  51.3  275  12  6   7.7   4.2 |  10.4  50.7  270   5  3   9.4   5.1
 11000  11.2  52.2  280  12  6   6.8   3.7 |  11.1  52.0  275   5  2  10.2   5.6
 10750  11.7  53.1  280  13  6   7.0   3.8 |  11.8  53.2  275   5  2   9.9   5.4
 10500  12.2  54.0  280  13  7   6.8   3.7 |  12.6  54.7  275   5  2  10.2   5.6
 10250  12.7  54.9  280  13  7   7.6   4.1 |  13.3  55.9  275   4  2   8.3   4.6
 10000  13.3  55.9  280  12  6   8.4   4.6 |  13.9  57.0  275   4  2   9.0   4.9
  9750  13.9  57.0  280  12  6   8.4   4.6 |  14.7  58.5  275   4  2  11.1   6.1
  9500  14.5  58.1  280  12  6   8.4   4.6 |  15.5  59.9  280   4  2  10.6   5.8
  9250  15.1  59.2  280  12  6   8.4   4.6 |  16.2  61.2  280   4  2   9.7   5.3
  9000  15.7  60.3  280  11  6   8.6   4.7 |  16.9  62.4  280   4  2   9.4   5.1
  8750  16.3  61.3  280  11  6   9.0   4.9 |  17.7  63.9  280   4  2  10.6   5.8
  8500  17.0  62.6  280  11  6   9.1   5.0 |  18.5  65.3  285   4  2  11.0   6.0
  8250  17.6  63.7  280  11  6   8.2   4.5 |  19.3  66.7  285   4  2  10.5   5.8
  8000  18.1  64.6  280  10  5   7.3   4.0 |  20.1  68.2  285   4  2  10.7   5.9
  7750  18.6  65.5  280  10  5   8.5   4.7 |  20.9  69.6  285   4  2   9.6   5.3
  7500  19.2  66.6  275   8  4   9.1   5.0 |  21.5  70.7  285   4  2  10.0   5.5
  7250  19.8  67.6  275   7  4   7.7   4.3 |  22.4  72.3  285   3  2  13.3   7.3
  7000  20.3  68.5  275   6  3   7.5   4.1 |  23.4  74.1  290   3  2  14.3   7.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/20/2014 at 1500 MDT          |       08/20/2014 at 1800 MDT
                                           |
K index... +30.2  LI... -2.0               | K index... +29.7  LI... -2.1
CAPE... +326.2  CIN... -5.3                | CAPE... +216.9  CIN... -5.6
                                           |
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 -65.4 -85.7  250  34 18   0.9   0.5 | -65.0 -85.0  250  32 16   0.5   0.3
 45000 -61.3 -78.3  255  50 26   6.4   3.5 | -61.2 -78.2  250  46 24   6.6   3.6
 40000 -51.6 -60.9  245  46 24   7.3   4.0 | -51.1 -60.0  240  46 24   7.2   4.0
 38000 -47.2 -53.0  240  44 23   7.3   4.0 | -46.8 -52.2  240  45 23   7.2   4.0
 36000 -42.8 -45.0  235  42 22   7.2   3.9 | -42.4 -44.3  240  44 22   7.1   3.9
 34000 -37.4 -35.3  230  39 20   8.2   4.5 | -36.9 -34.4  230  41 21   8.3   4.5
 32000 -32.5 -26.5  220  37 19   8.5   4.7 | -31.9 -25.4  225  40 21   8.5   4.7
 30000 -27.7 -17.9  225  34 18   7.9   4.3 | -27.4 -17.3  225  40 20   7.5   4.1
 29000 -25.3 -13.5  225  33 17   7.9   4.4 | -25.1 -13.2  230  40 20   7.6   4.1
 28000 -23.0  -9.4  225  31 16   7.3   4.0 | -22.9  -9.2  230  40 20   7.1   3.9
 27000 -20.9  -5.6  230  31 16   7.1   3.9 | -20.9  -5.6  235  38 19   7.0   3.8
 26000 -18.7  -1.7  230  31 16   7.2   3.9 | -18.8  -1.8  240  36 19   7.0   3.8
 25000 -16.6   2.1  235  31 16   7.2   3.9 | -16.7   1.9  245  35 18   7.0   3.9
 24000 -14.6   5.7  240  29 15   6.7   3.7 | -14.8   5.4  245  32 16   6.6   3.6
 23000 -12.6   9.3  245  27 14   6.7   3.7 | -12.8   9.0  245  28 15   6.6   3.6
 22000 -10.6  12.9  245  25 13   6.7   3.7 | -10.9  12.4  245  25 13   6.6   3.6
 21000  -8.9  16.0  250  24 12   5.7   3.2 |  -9.2  15.4  245  22 11   5.6   3.1
 20000  -7.2  19.0  245  23 12   5.8   3.2 |  -7.6  18.3  245  19 10   5.7   3.1
 19500  -6.4  20.5  245  22 11   5.9   3.2 |  -6.8  19.8  245  18  9   5.7   3.1
 19000  -5.6  21.9  245  21 11   6.0   3.3 |  -5.9  21.4  245  16  8   6.3   3.5
 18500  -4.8  23.4  250  20 11   6.0   3.3 |  -5.0  23.0  240  14  7   6.5   3.6
 18000  -3.9  25.0  250  19 10   6.0   3.3 |  -4.1  24.6  235  11  6   6.5   3.6
 17500  -3.1  26.4  250  18  9   6.2   3.4 |  -3.2  26.2  235  10  5   6.1   3.4
 17000  -2.2  28.0  255  16  8   6.2   3.4 |  -2.3  27.9  240  10  5   6.2   3.4
 16500  -1.4  29.5  255  14  7   6.2   3.4 |  -1.4  29.5  240   9  5   6.5   3.6
 16000  -0.1  31.8  255  10  5   6.1   3.4 |   0.1  32.2  240   7  3   6.6   3.6
 15500   0.9  33.6  250   8  4   7.7   4.2 |   1.0  33.8  235   5  3   7.2   4.0
 15000   2.0  35.6  245   6  3   7.8   4.3 |   2.1  35.8  230   4  2   7.3   4.0
 14500   3.1  37.6  240   4  2   8.1   4.5 |   3.1  37.6  225   3  1   8.2   4.5
 14000   4.3  39.7  220   3  2   8.4   4.6 |   4.4  39.9  220   2  1   8.8   4.8
 13500   5.5  41.9  195   3  1   8.6   4.7 |   5.6  42.1  210   2  1   9.0   4.9
 13000   6.8  44.2  185   3  2   9.0   4.9 |   7.0  44.6  210   2  1   9.3   5.1
 12500   8.2  46.8  185   4  2  10.5   5.8 |   8.4  47.1  210   2  1  10.3   5.6
 12000   9.7  49.5  175   4  2   9.2   5.0 |   9.9  49.8  205   1  1   9.4   5.2
 11750  10.4  50.7  175   4  2  10.1   5.5 |  10.6  51.1  205   1  1  10.0   5.5
 11500  11.1  52.0  175   5  2   7.9   4.3 |  11.3  52.3  200   2  1   8.8   4.8
 11250  11.6  52.9  175   5  2   8.5   4.7 |  11.9  53.4  205   2  1   9.0   5.0
 11000  12.4  54.3  175   5  3  11.1   6.1 |  12.7  54.9  200   2  1  10.4   5.7
 10750  13.2  55.8  175   5  3  10.3   5.7 |  13.5  56.3  195   2  1  10.0   5.5
 10500  14.0  57.2  175   5  3  10.8   5.9 |  14.2  57.6  195   2  1  10.3   5.6
 10250  14.8  58.6  170   5  3   8.8   4.8 |  14.9  58.8  190   2  1   8.5   4.6
 10000  15.4  59.7  170   6  3   9.1   5.0 |  15.5  59.9  185   2  1   8.7   4.8
  9750  16.2  61.2  170   6  3  11.0   6.0 |  16.3  61.3  185   2  1  10.5   5.8
  9500  17.0  62.6  170   6  3  10.6   5.8 |  17.0  62.6  185   2  1  10.0   5.5
  9250  17.7  63.9  170   6  3   9.9   5.4 |  17.8  64.0  180   2  1  10.1   5.5
  9000  18.4  65.1  170   6  3   9.4   5.2 |  18.5  65.3  180   2  1  10.0   5.5
  8750  19.2  66.6  170   6  3  10.2   5.6 |  19.3  66.7  180   2  1  10.1   5.5
  8500  19.9  67.8  170   6  3  10.4   5.7 |  20.0  68.0  180   2  1  10.1   5.6
  8250  20.7  69.3  170   6  3  10.3   5.6 |  20.8  69.4  175   2  1   9.9   5.4
  8000  21.5  70.7  165   6  3  10.6   5.8 |  21.5  70.7  175   2  1   9.9   5.4
  7750  22.3  72.1  165   6  3   9.5   5.2 |  22.2  72.0  175   2  1   9.3   5.1
  7500  22.9  73.2  165   6  3   9.5   5.2 |  22.9  73.2  175   2  1   8.3   4.5
  7250  23.7  74.7  165   6  3  12.4   6.8 |  23.5  74.3  175   2  1   7.8   4.3
  7000  24.7  76.5  165   6  3  13.7   7.5 |  24.0  75.2  170   2  1   7.2   3.9
  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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