Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 151032
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Soaring Forecast
National Weather Service Pueblo, Colorado
0431 MDT Tuesday, April 15, 2014

This forecast is for Tuesday, April 15, 2014:

If the trigger temperature of 45.1 F/7.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 746 ft/min (3.8 m/s)
   Maximum height of thermals.................. 15604 ft MSL (8846 ft AGL)

Forecast maximum temperature................... 55.0 F/13.2 C
Time of trigger temperature.................... 1100 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................. 13678 ft MSL (6920 ft AGL)
Thermal soaring outlook for Wednesday 04/16.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 45210 ft MSL (38452 ft AGL)
Wave soaring outlook for Wednesday 04/16....... Fair

Remarks...

Sunrise/Sunset.................... 06:22:28 / 19:35:16 MDT
Total possible sunshine........... 13 hr 12 min 49 sec (792 min 49 sec)
Altitude of sun at 12:59:01 MDT... 60.99 degrees

Upper air data from numerical model forecast valid on 04/15/2014 at 0600 MDT

Freezing level.................. 7208 ft MSL (450 ft AGL)
Additional freezing level....... 9494 ft MSL (2736 ft AGL)
Convective condensation level... 21780 ft MSL (15022 ft AGL)
Lifted condensation level....... 18880 ft MSL (12122 ft AGL)
Lifted index.................... +5.8
K index......................... -10.2

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  -60.6 -77.1   295   41   21   0.9   0.5      M     M       M      M    M
 45000  -59.2 -74.6   305   49   25   0.6   0.3      M     M       M      M    M
 40000  -62.8 -81.0   305   46   23  -2.5  -1.4      M     M       M      M    M
 38000  -61.9 -79.4   305   45   23   6.7   3.7      M     M       M      M    M
 36000  -57.9 -72.2   305   47   24   6.6   3.6      M     M       M      M    M
 34000  -53.8 -64.8   300   49   25   8.2   4.5      M     M       M      M    M
 32000  -48.3 -54.9   300   47   24   8.1   4.4      M     M       M      M    M
 30000  -43.6 -46.5   300   46   24   7.5   4.1   26.5  79.7    10.5      M    M
 29000  -41.3 -42.3   300   44   23   7.4   4.1   25.5  77.9     9.9      M    M
 28000  -39.1 -38.4   305   42   22   7.5   4.1   24.7  76.4     9.3      M    M
 27000  -36.9 -34.4   305   41   21   7.7   4.2   24.0  75.1     8.9      M    M
 26000  -34.5 -30.1   305   40   20   7.8   4.3   23.1  73.6     8.3      M    M
 25000  -32.2 -26.0   310   39   20   7.8   4.3   22.4  72.3     7.8      M    M
 24000  -29.8 -21.6   315   38   20   7.9   4.3   21.8  71.3     7.4      M    M
 23000  -27.5 -17.5   315   37   19   8.4   4.4   21.1  69.9     6.9      M    M
 22000  -25.1 -13.2   320   37   19   8.0   4.4   20.4  68.8     6.4      M    M
 21000  -22.7  -8.9   325   36   18   7.2   3.9   19.8  67.7     6.0      M    M
 20000  -20.6  -5.1   325   35   18   6.8   3.8   18.7  65.7     5.1      M    M
 19500  -19.6  -3.3   325   34   18   6.8   3.8   18.3  64.9     4.7      M    M
 19000  -18.6  -1.5   325   34   17   6.8   3.7   17.8  64.0     4.3      M    M
 18500  -17.6   0.3   325   33   17   6.4   3.5   17.3  63.2     4.0      M    M
 18000  -16.7   1.9   325   33   17   5.8   3.2   16.7  62.0     3.4      M    M
 17500  -15.8   3.6   330   32   16   5.9   3.2   16.0  60.8     2.8      M    M
 17000  -15.0   5.0   330   31   16   5.2   2.9   15.3  59.5     2.2      M    M
 16500  -14.2   6.4   330   30   16   5.3   2.9   14.5  58.2     1.5      M    M
 16000  -13.1   8.4   330   28   15   4.7   2.6   13.4  56.1     0.4      M    M
 15500  -12.4   9.7   330   27   14   4.7   2.6   12.5  54.6    -0.3    730  3.7
 15000  -11.7  10.9   325   25   13   4.6   2.5   11.7  53.1    -1.1    695  3.5
 14500  -11.0  12.2   325   23   12   4.6   2.5   10.9  51.6    -1.9    659  3.3
 14000  -10.3  13.5   325   21   11   4.9   2.7   10.1  50.1    -2.7    623  3.2
 13500   -9.6  14.7   325   19   10   5.0   2.7    9.3  48.7    -3.4    586  3.0
 13000   -8.8  16.2   330   18    9   6.6   3.6    8.6  47.5    -4.1    547  2.8
 12500   -7.7  18.1   330   17    9   7.4   4.1    8.2  46.7    -4.5    500  2.5
 12000   -6.6  20.1   335   16    8   7.7   4.2    7.7  45.9    -4.9    454  2.3
 11750   -6.0  21.2   335   17    8   9.4   5.2    7.7  45.8    -5.0    427  2.2
 11500   -5.3  22.5   340   17    9   9.3   5.1    7.6  45.7    -5.1    399  2.0
 11250   -4.6  23.7   340   17    9   8.2   4.5    7.6  45.6    -5.1    371  1.9
 11000   -4.0  24.8   340   17    9   8.7   4.8    7.4  45.4    -5.3    346  1.8
 10750   -3.3  26.1   340   18    9  10.2   5.6    7.4  45.4    -5.3    316  1.6
 10500   -2.5  27.5   340   18    9  10.0   5.5    7.5  45.4    -5.3    286  1.5
 10250   -1.8  28.8   340   19   10   9.3   5.1    7.5  45.4    -5.3    257  1.3
 10000   -1.2  29.8   340   19   10   7.6   4.2    7.4  45.3    -5.4    231  1.2
  9750   -0.6  30.9   340   20   10   8.1   4.4    7.2  45.0    -5.6    206  1.0
  9500    0.1  32.2   335   20   10   9.1   5.0    7.1  44.8    -5.7    179  0.9
  9250    0.7  33.3   330   21   11   8.0   4.4    7.0  44.7    -5.8    152  0.8
  9000    1.3  34.3   330   21   11   7.1   3.9    6.9  44.3    -6.0    129  0.7
  8750    1.8  35.2   325   20   10   6.0   3.3    6.6  43.9    -6.2    106  0.5
  8500    2.2  36.0   315   20   10   5.7   3.1    6.3  43.3    -6.6     87  0.4
  8250    2.5  36.5   310   19   10  -0.2  -0.1    5.9  42.6    -7.0     70  0.4
  8000    2.1  35.8   305   17    9  -8.4  -4.6    4.7  40.5    -8.2     75  0.4
  7750    1.6  34.9   300   16    8   2.2   1.2    3.6  38.5    -9.4     80  0.4
  7500    1.9  35.4   285   13    7  -3.8  -2.1    3.2  37.7    -9.8     64  0.3
  7250    0.5  32.9   280   10    5 -31.5 -17.3    1.3  34.3   -11.8    100  0.5
  7000   -2.3  27.9   280    8    4 -37.0 -20.3   -1.7  28.9   -14.8    177  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/15/2014 at 0900 MDT          |       04/15/2014 at 1200 MDT
                                           |
K index... -10.8  LI... +5.8               | K index... -6.3  LI... +4.2
CAPE... 0.0  CIN... M                      | 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 -59.7 -75.5  300  40 20   0.5   0.3 | -59.9 -75.8  295  40 21   1.1   0.6
 45000 -58.9 -74.0  300  50 26   0.4   0.2 | -58.3 -72.9  295  48 25   1.1   0.6
 40000 -62.3 -80.1  295  47 24  -2.4  -1.3 | -61.8 -79.2  295  60 31  -2.5  -1.4
 38000 -61.6 -78.9  295  49 25   5.9   3.2 | -61.4 -78.5  295  64 33   5.5   3.0
 36000 -58.1 -72.6  300  53 27   5.8   3.2 | -58.1 -72.6  295  67 34   5.5   3.0
 34000 -53.7 -64.7  305  57 29   9.0   4.9 | -54.0 -65.2  290  68 35   8.7   4.8
 32000 -48.2 -54.8  300  54 28   9.1   5.0 | -48.7 -55.7  290  64 33   8.7   4.8
 30000 -42.9 -45.2  300  52 27   7.7   4.2 | -43.7 -46.7  290  59 31   7.6   4.2
 29000 -40.7 -41.3  300  50 26   7.6   4.2 | -41.4 -42.5  290  57 29   7.5   4.1
 28000 -38.4 -37.1  300  49 25   7.6   4.2 | -39.1 -38.4  290  54 28   7.5   4.1
 27000 -36.1 -33.0  300  47 24   6.9   3.8 | -36.9 -34.4  290  52 27   7.7   4.2
 26000 -34.2 -29.6  300  47 24   6.3   3.5 | -34.5 -30.1  290  50 26   7.9   4.4
 25000 -32.3 -26.1  300  46 24   6.3   3.5 | -32.1 -25.8  290  47 24   7.9   4.4
 24000 -30.4 -22.7  300  45 23   6.9   3.8 | -29.7 -21.5  290  45 23   7.8   4.3
 23000 -27.9 -18.2  295  42 22   8.5   4.7 | -27.5 -17.5  290  43 22   7.3   4.0
 22000 -25.4 -13.7  295  39 20   8.5   4.7 | -25.4 -13.7  290  41 21   7.3   4.0
 21000 -22.8  -9.0  290  35 18   7.9   4.4 | -23.2  -9.8  290  39 20   7.0   3.9
 20000 -20.5  -4.9  295  34 17   7.7   4.2 | -21.1  -6.0  290  36 19   6.9   3.8
 19500 -19.4  -2.9  300  33 17   7.7   4.2 | -20.1  -4.2  290  35 18   6.9   3.8
 19000 -18.2  -0.8  300  32 16   7.6   4.2 | -19.0  -2.2  290  34 17   7.0   3.8
 18500 -17.1   1.2  305  31 16   6.9   3.8 | -18.0  -0.4  290  32 17   7.1   3.9
 18000 -16.2   2.8  305  30 16   6.0   3.3 | -16.9   1.6  290  31 16   7.3   4.0
 17500 -15.3   4.5  310  29 15   6.0   3.3 | -15.8   3.6  290  29 15   7.2   4.0
 17000 -14.4   6.1  310  28 14   5.8   3.2 | -14.7   5.5  295  28 14   7.7   4.2
 16500 -13.5   7.7  315  26 14   5.9   3.2 | -13.0   8.6  295  26 13   7.6   4.2
 16000 -12.2  10.0  315  24 13   5.7   3.2 | -11.9  10.6  290  24 13   7.1   3.9
 15500 -11.4  11.5  315  23 12   5.7   3.1 | -10.8  12.6  290  23 12   7.2   4.0
 15000 -10.5  13.1  315  22 11   6.1   3.4 |  -9.8  14.4  290  21 11   6.2   3.4
 14500  -9.5  14.9  315  21 11   6.2   3.4 |  -8.9  16.0  290  20 10   6.3   3.4
 14000  -8.7  16.3  315  19 10   5.4   2.9 |  -8.0  17.6  290  18  9   6.0   3.3
 13500  -7.9  17.8  315  17  9   5.2   2.8 |  -7.1  19.2  290  17  9   5.9   3.3
 13000  -7.1  19.2  310  15  8   5.8   3.2 |  -6.2  20.8  285  16  8   6.4   3.5
 12500  -6.2  20.8  310  13  7   6.6   3.6 |  -5.2  22.6  285  15  8   6.9   3.8
 12000  -5.5  22.1  305  12  6   4.9   2.7 |  -4.3  24.3  285  13  7   6.5   3.6
 11750  -5.0  23.0  310  11  6   8.3   4.5 |  -3.7  25.3  285  12  6   8.6   4.7
 11500  -4.4  24.1  310  11  5   7.4   4.0 |  -3.1  26.4  285  11  6   8.1   4.4
 11250  -3.8  25.2  315  10  5   7.6   4.2 |  -2.5  27.5  280  11  5   8.0   4.4
 11000  -3.2  26.2  315   9  5   8.7   4.8 |  -1.9  28.6  280  10  5   8.0   4.4
 10750  -2.5  27.5  315   9  5   9.5   5.2 |  -1.3  29.7  280  10  5   8.2   4.5
 10500  -1.8  28.8  320   9  5   9.4   5.2 |  -0.7  30.7  275   9  5   8.3   4.6
 10250  -1.1  30.0  320   9  5   9.0   4.9 |  -0.1  31.8  275   9  5   7.7   4.2
 10000  -0.5  31.1  325   9  5   8.3   4.5 |   0.5  32.9  270   9  5   6.8   3.7
  9750   0.1  32.2  325  10  5   9.0   5.0 |   1.0  33.8  265   8  4   8.4   4.6
  9500   0.9  33.6  325  10  5   9.9   5.4 |   1.7  35.1  260   8  4   9.8   5.4
  9250   1.6  34.9  325  11  6   9.1   5.0 |   2.4  36.3  250   7  4   8.6   4.7
  9000   2.2  36.0  320  11  6   8.4   4.6 |   2.9  37.2  240   7  4   6.3   3.5
  8750   2.8  37.0  315  12  6   6.9   3.8 |   3.3  37.9  230   7  4   8.0   4.4
  8500   3.3  37.9  305  13  7   7.0   3.9 |   4.1  39.4  220   7  4  10.3   5.6
  8250   3.8  38.8  300  14  7   3.7   2.0 |   4.8  40.6  215   7  4   9.2   5.1
  8000   3.8  38.8  295  13  7  -1.0  -0.6 |   5.4  41.7  205   8  4   9.0   4.9
  7750   3.7  38.7  285  12  6   3.0   1.7 |   6.0  42.8  200   9  4   8.6   4.7
  7500   4.1  39.4  275  10  5   4.6   2.5 |   6.7  44.1  195   9  4   8.1   4.5
  7250   4.2  39.6  265   8  4  -0.9  -0.5 |   7.2  45.0  190   8  4   8.3   4.5
  7000   3.8  38.8  260   6  3  -4.4  -2.4 |   7.8  46.0  190   8  4   8.5   4.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/15/2014 at 1500 MDT          |       04/15/2014 at 1800 MDT
                                           |
K index... +6.9  LI... +0.9                | K index... +2.9  LI... +0.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -44.9
                                           |
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 -59.5 -75.1  290  43 22   1.6   0.9 | -59.4 -74.9  295  39 20   2.2   1.2
 45000 -57.1 -70.8  290  47 24   1.8   1.0 | -56.1 -69.0  290  54 28   2.9   1.6
 40000 -62.0 -79.6  290  63 33  -3.5  -1.9 | -61.4 -78.5  280  68 35  -3.8  -2.1
 38000 -61.8 -79.2  290  69 35   6.1   3.3 | -61.6 -78.9  280  72 37   5.7   3.1
 36000 -58.2 -72.8  290  71 37   6.0   3.3 | -58.2 -72.8  280  73 38   5.6   3.1
 34000 -53.9 -65.0  285  73 37   8.2   4.5 | -54.2 -65.6  280  73 38   8.4   4.6
 32000 -48.9 -56.0  285  69 36   8.2   4.5 | -49.2 -56.6  280  69 36   8.3   4.5
 30000 -44.0 -47.2  290  65 33   8.1   4.4 | -44.2 -47.6  280  65 33   7.9   4.4
 29000 -41.6 -42.9  290  62 32   8.2   4.5 | -41.8 -43.2  285  62 32   8.0   4.4
 28000 -39.1 -38.4  290  59 31   8.2   4.5 | -39.4 -38.9  285  58 30   8.0   4.4
 27000 -36.7 -34.1  285  57 29   8.0   4.4 | -37.0 -34.6  285  55 28   7.8   4.3
 26000 -34.4 -29.9  285  55 29   7.7   4.2 | -34.9 -30.8  285  51 26   7.2   3.9
 25000 -32.0 -25.6  285  54 28   7.7   4.3 | -32.7 -26.9  290  46 24   7.2   3.9
 24000 -29.7 -21.5  285  53 27   7.6   4.2 | -30.6 -23.1  290  42 21   7.2   3.9
 23000 -27.8 -18.0  285  49 25   6.3   3.4 | -28.7 -19.7  290  41 21   6.0   3.3
 22000 -25.9 -14.6  285  46 23   6.3   3.4 | -26.9 -16.4  290  41 21   6.0   3.3
 21000 -24.0 -11.2  285  42 21   6.9   3.8 | -25.1 -13.2  290  41 21   7.1   3.9
 20000 -21.8  -7.2  285  39 20   7.5   4.1 | -22.7  -8.9  290  40 20   8.3   4.5
 19500 -20.6  -5.1  290  37 19   7.5   4.1 | -21.4  -6.5  290  39 20   8.3   4.5
 19000 -19.5  -3.1  290  36 18   7.5   4.1 | -20.2  -4.4  290  38 20   8.3   4.5
 18500 -18.4  -1.1  290  34 18   7.5   4.1 | -18.9  -2.0  290  37 19   8.2   4.5
 18000 -17.3   0.9  290  33 17   7.5   4.1 | -17.7   0.1  290  36 19   8.0   4.4
 17500 -16.2   2.8  290  32 16   7.6   4.1 | -16.5   2.3  290  35 18   8.0   4.4
 17000 -15.1   4.8  290  31 16   7.3   4.0 | -15.4   4.3  295  35 18   7.8   4.3
 16500 -13.4   7.9  290  29 15   7.3   4.0 | -14.2   6.4  295  35 18   7.8   4.3
 16000 -12.3   9.9  290  28 14   7.8   4.3 | -12.4   9.7  300  35 18   8.8   4.8
 15500 -11.1  12.0  290  27 14   7.8   4.3 | -11.1  12.0  300  34 18   8.7   4.8
 15000 -10.0  14.0  290  27 14   7.7   4.2 |  -9.8  14.4  300  34 17   8.3   4.5
 14500  -8.8  16.2  290  26 13   7.7   4.2 |  -8.6  16.5  300  34 17   8.2   4.5
 14000  -7.7  18.1  290  26 13   7.8   4.3 |  -7.3  18.9  300  34 17   8.2   4.5
 13500  -6.5  20.3  290  25 13   7.9   4.3 |  -6.1  21.0  300  33 17   8.2   4.5
 13000  -5.3  22.5  290  25 13   7.9   4.3 |  -4.9  23.2  300  32 17   8.2   4.5
 12500  -4.2  24.4  285  23 12   7.9   4.4 |  -3.7  25.3  295  31 16   8.1   4.5
 12000  -3.0  26.6  275  21 11   8.2   4.5 |  -2.6  27.3  290  30 15   6.8   3.7
 11750  -2.4  27.7  275  20 10   8.3   4.6 |  -2.1  28.2  290  29 15   8.2   4.5
 11500  -1.8  28.8  270  19 10   7.8   4.3 |  -1.5  29.3  290  28 14   8.1   4.4
 11250  -1.2  29.8  265  18  9   9.7   5.3 |  -0.9  30.4  285  27 14   8.1   4.4
 11000  -0.4  31.3  265  17  9  10.2   5.6 |  -0.3  31.5  285  26 14   8.2   4.5
 10750   0.2  32.4  265  16  8   8.6   4.7 |   0.3  32.5  280  25 13   8.4   4.6
 10500   0.9  33.6  260  16  8   9.0   5.0 |   0.9  33.6  280  24 12   8.5   4.6
 10250   1.5  34.7  255  15  8   8.7   4.8 |   1.5  34.7  275  23 12   8.4   4.6
 10000   2.1  35.8  250  14  7   6.7   3.7 |   2.1  35.8  275  22 11   8.8   4.8
  9750   2.6  36.7  245  13  7   8.0   4.4 |   2.8  37.0  270  21 11   9.7   5.3
  9500   3.3  37.9  240  13  7  10.3   5.6 |   3.5  38.3  270  20 10   9.9   5.4
  9250   4.0  39.2  235  12  6   9.5   5.2 |   4.3  39.7  270  19 10   9.9   5.4
  9000   4.7  40.5  230  12  6   8.8   4.8 |   5.0  41.0  265  18  9   9.1   5.0
  8750   5.4  41.7  225  12  6   9.4   5.2 |   5.6  42.1  265  17  9   9.5   5.2
  8500   6.1  43.0  220  12  6  10.5   5.8 |   6.4  43.5  265  17  9  10.6   5.8
  8250   6.9  44.4  220  12  6  10.2   5.6 |   7.1  44.8  260  16  8  10.0   5.5
  8000   7.7  45.9  215  11  6  10.6   5.8 |   7.8  46.0  260  15  8   9.4   5.2
  7750   8.4  47.1  215  11  6   9.6   5.3 |   8.5  47.3  260  14  7   8.3   4.6
  7500   9.0  48.2  210  10  5   8.0   4.4 |   9.1  48.4  260  13  7   8.6   4.7
  7250   9.6  49.3  205  10  5   9.1   5.0 |   9.6  49.3  255  11  6   5.6   3.1
  7000  10.3  50.5  205   9  5  11.3   6.2 |   9.7  49.5  255   9  5  -1.8  -1.0
  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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