Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 311139
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0539 MDT Thursday, July 31, 2014

This forecast is for Thursday, July 31, 2014:

If the trigger temperature of 62.8 F/17.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 471 ft/min (2.4 m/s)
   Maximum height of thermals.................. 13283 ft MSL (6113 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11637 ft MSL (4467 ft AGL)
Thermal soaring outlook for Friday 08/01....... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12335 ft MSL (5165 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 14548 ft MSL (7378 ft AGL)
Wave soaring outlook for Friday 08/01.......... Poor

Remarks...

Sunrise/Sunset.................... 05:59:02 / 20:12:00 MDT
Total possible sunshine........... 14 hr 12 min 57 sec (852 min 57 sec)
Altitude of sun at 13:05:18 MDT... 69.17 degrees

Upper air data from numerical model forecast valid on 07/31/2014 at 0600 MDT

Freezing level.................. 14684 ft MSL (7514 ft AGL)
Convective condensation level... 11498 ft MSL (4328 ft AGL)
Lifted condensation level....... 12910 ft MSL (5739 ft AGL)
Lifted index.................... -1.0
K index......................... +27.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.4 -82.1   310   32   16   1.7   0.9      M     M       M      M    M
 45000  -59.7 -75.5   295   54   28   4.3   2.4      M     M       M      M    M
 40000  -52.2 -62.0   295   73   38   7.3   4.0      M     M       M      M    M
 38000  -47.9 -54.2   300   68   35   7.3   4.0      M     M       M      M    M
 36000  -43.5 -46.3   300   62   32   7.3   4.0      M     M       M      M    M
 34000  -39.0 -38.2   305   55   28   7.6   4.2      M     M       M      M    M
 32000  -34.4 -29.9   305   47   24   7.5   4.1      M     M       M      M    M
 30000  -29.8 -21.6   310   43   22   7.8   4.3   41.1 105.9    15.5      M    M
 29000  -27.5 -17.5   310   41   21   7.8   4.3   40.4 104.6    15.1      M    M
 28000  -25.1 -13.2   310   39   20   7.1   3.9   39.8 103.6    14.8      M    M
 27000  -23.2  -9.8   310   35   18   6.6   3.6   38.4 101.2    13.8      M    M
 26000  -21.3  -6.3   305   32   16   6.7   3.7   37.3  99.1    13.0      M    M
 25000  -19.3  -2.7   305   28   15   6.9   3.8   36.3  97.3    12.2      M    M
 24000  -16.9   1.6   305   26   14   6.8   3.7   34.9  94.8    11.1      M    M
 23000  -14.9   5.2   305   25   13   6.8   3.7   33.8  92.8    10.3      M    M
 22000  -12.9   8.8   305   24   12   6.2   3.4   32.8  91.1     9.6      M    M
 21000  -11.2  11.8   305   22   11   5.8   3.2   31.4  88.5     8.4      M    M
 20000   -9.5  14.9   300   20   10   5.9   3.2   30.0  86.1     7.2      M    M
 19500   -8.7  16.3   300   19   10   5.9   3.2   29.4  85.0     6.7      M    M
 19000   -7.8  18.0   300   18   10   6.0   3.3   28.8  83.8     6.1      M    M
 18500   -7.0  19.4   300   18    9   6.0   3.3   28.1  82.7     5.6      M    M
 18000   -6.1  21.0   300   18    9   6.2   3.4   27.5  81.6     5.0      M    M
 17500   -5.2  22.6   305   18    9   6.3   3.4   26.9  80.5     4.5      M    M
 17000   -4.3  24.3   305   17    9   6.3   3.5   26.4  79.5     3.9      M    M
 16500   -3.4  25.9   300   17    9   6.2   3.4   25.8  78.4     3.4      M    M
 16000   -2.5  27.5   300   17    9   6.2   3.4   25.2  77.4     2.8      M    M
 15500   -1.6  29.1   295   17    9   6.6   3.6   24.6  76.4     2.3      M    M
 15000   -0.7  30.7   290   18    9   6.6   3.6   24.1  75.4     1.8      M    M
 14500    0.3  32.5   280   18    9   6.9   3.8   23.6  74.5     1.3      M    M
 14000    1.3  34.3   275   17    9   7.1   3.9   23.2  73.8     0.8      M    M
 13500    2.3  36.1   265   17    9   6.3   3.5   22.8  73.1     0.4      M    M
 13000    3.0  37.4   260   15    8   4.3   2.4   22.0  71.6    -0.4    457  2.3
 12500    3.6  38.5   255   13    7   3.9   2.2   21.2  70.1    -1.2    424  2.2
 12000    4.1  39.4   245   11    6   3.7   2.0   20.2  68.3    -2.2    395  2.0
 11750    4.4  39.9   240   11    6   4.2   2.3   19.7  67.5    -2.6    379  1.9
 11500    4.7  40.5   235   10    5   4.0   2.2   19.3  66.7    -3.1    362  1.8
 11250    4.9  40.8   230   10    5   3.8   2.1   18.8  65.9    -3.5    347  1.8
 11000    5.2  41.4   220    9    5   3.7   2.0   18.3  65.0    -4.0    331  1.7
 10750    5.5  41.9   210    9    5   3.9   2.1   17.9  64.2    -4.4    315  1.6
 10500    5.8  42.4   205    9    5   4.0   2.2   17.4  63.4    -4.9    299  1.5
 10250    6.1  43.0   200   10    5   4.3   2.4   17.0  62.6    -5.3    283  1.4
 10000    6.4  43.5   195   10    5   4.7   2.6   16.6  61.9    -5.8    266  1.4
  9750    7.0  44.6   185   11    6   3.7   2.0   15.7  60.3    -6.7    234  1.2
  9500    7.3  45.1   185   11    6   4.5   2.5   15.3  59.5    -7.1    218  1.1
  9250    7.6  45.7   185   11    6   5.0   2.8   14.9  58.8    -7.5    200  1.0
  9000    8.0  46.4   180   11    6   4.0   2.2   14.5  58.1    -7.9    182  0.9
  8750    8.2  46.8   180   12    6   4.1   2.2   14.1  57.3    -8.4    168  0.9
  8500    8.5  47.3   175   12    6   5.8   3.2   13.7  56.7    -8.8    150  0.8
  8250    8.9  48.0   175   11    6   5.9   3.3   13.4  56.1    -9.2    131  0.7
  8000    9.3  48.7   175   11    6   5.9   3.3   13.1  55.6    -9.5    111  0.6
  7750    9.8  49.6   180   10    5   7.1   3.9   12.9  55.2    -9.8     91  0.5
  7500   10.3  50.5   175    8    4   9.1   5.0   12.8  55.0   -10.0     67  0.3
  7250   10.9  51.6   170    6    3   5.8   3.2   12.6  54.8   -10.2     43  0.2
  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 * * * * * *

           07/31/2014 at 0900 MDT          |       07/31/2014 at 1200 MDT
                                           |
K index... +28.3  LI... -1.3               | K index... +27.7  LI... -0.5
CAPE... +55.8  CIN... -5.5                 | CAPE... +30.9  CIN... -12.3
                                           |
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 -63.8 -82.8  305  29 15   1.2   0.6 | -63.0 -81.4  305  29 15   2.1   1.1
 45000 -60.6 -77.1  295  54 28   4.5   2.4 | -59.3 -74.7  295  55 28   3.3   1.8
 40000 -53.5 -64.3  295  73 38   7.1   3.9 | -53.2 -63.8  290  73 38   7.3   4.0
 38000 -48.6 -55.5  300  65 33   7.2   3.9 | -48.8 -55.8  295  64 33   7.3   4.0
 36000 -44.3 -47.7  305  57 29   7.4   4.1 | -44.4 -47.9  295  55 28   7.5   4.1
 34000 -39.4 -38.9  305  49 25   8.3   4.6 | -39.5 -39.1  300  45 23   8.4   4.6
 32000 -34.4 -29.9  310  41 21   8.3   4.6 | -34.4 -29.9  300  36 19   8.3   4.6
 30000 -29.7 -21.5  315  38 20   7.8   4.3 | -29.5 -21.1  305  33 17   8.3   4.5
 29000 -27.3 -17.1  315  38 19   7.8   4.3 | -27.0 -16.6  305  32 16   8.3   4.5
 28000 -25.0 -13.0  315  37 19   7.2   3.9 | -24.5 -12.1  305  31 16   7.5   4.1
 27000 -23.0  -9.4  315  35 18   6.7   3.7 | -22.5  -8.5  305  30 16   7.0   3.8
 26000 -21.0  -5.8  310  33 17   6.8   3.7 | -20.4  -4.7  310  30 15   7.0   3.9
 25000 -19.0  -2.2  310  31 16   6.9   3.8 | -17.9  -0.2  310  29 15   6.7   3.7
 24000 -16.6   2.1  310  28 15   6.6   3.6 | -16.0   3.2  310  27 14   6.4   3.5
 23000 -14.7   5.5  305  27 14   6.7   3.7 | -14.2   6.4  310  25 13   6.4   3.5
 22000 -12.8   9.0  305  25 13   6.3   3.5 | -12.3   9.9  305  24 12   6.5   3.5
 21000 -11.1  12.0  305  23 12   6.0   3.3 | -10.5  13.1  305  22 11   6.5   3.5
 20000  -9.4  15.1  305  21 11   6.1   3.3 |  -8.6  16.5  305  20 10   6.5   3.6
 19500  -8.5  16.7  305  20 11   6.1   3.4 |  -7.7  18.1  305  19 10   6.5   3.6
 19000  -7.6  18.3  305  20 10   6.1   3.4 |  -6.8  19.8  305  18  9   5.9   3.3
 18500  -6.7  19.9  305  19 10   6.2   3.4 |  -5.9  21.4  305  17  9   6.0   3.3
 18000  -5.9  21.4  305  18  9   6.1   3.3 |  -5.1  22.8  310  16  8   5.6   3.1
 17500  -5.0  23.0  310  17  9   6.1   3.3 |  -4.3  24.3  310  15  8   5.4   2.9
 17000  -4.1  24.6  310  17  9   6.1   3.3 |  -3.5  25.7  310  14  7   5.3   2.9
 16500  -3.3  26.1  310  16  8   6.1   3.4 |  -2.8  27.0  315  13  7   4.8   2.6
 16000  -2.4  27.7  310  16  8   6.1   3.4 |  -2.1  28.2  315  12  6   4.8   2.6
 15500  -1.5  29.3  305  15  8   6.3   3.5 |  -1.4  29.5  320  11  6   5.6   3.1
 15000  -0.6  30.9  300  15  8   6.4   3.5 |  -0.6  30.9  320  11  5   5.7   3.1
 14500   0.3  32.5  295  15  8   7.1   3.9 |   0.2  32.4  320  10  5   6.9   3.8
 14000   1.4  34.5  290  14  7   7.5   4.1 |   1.4  34.5  320   9  5   7.8   4.3
 13500   2.5  36.5  285  13  7   6.6   3.6 |   2.5  36.5  325   8  4   7.5   4.1
 13000   3.2  37.8  275  13  7   4.8   2.6 |   3.5  38.3  320   8  4   6.5   3.6
 12500   3.9  39.0  265  12  6   4.0   2.2 |   4.4  39.9  320   8  4   5.3   2.9
 12000   4.3  39.7  255  12  6   3.3   1.8 |   5.0  41.0  310   7  4   4.7   2.6
 11750   4.5  40.1  250  11  6   3.9   2.1 |   5.3  41.5  310   7  3   5.5   3.0
 11500   4.8  40.6  245  11  6   3.8   2.1 |   5.7  42.3  305   6  3   5.3   2.9
 11250   5.1  41.2  240  11  6   3.8   2.1 |   6.1  43.0  305   6  3   4.8   2.7
 11000   5.4  41.7  230  11  6   3.8   2.1 |   6.4  43.5  290   5  3   4.9   2.7
 10750   5.6  42.1  225  11  6   3.6   2.0 |   6.8  44.2  280   4  2   5.4   3.0
 10500   5.9  42.6  220  11  6   3.8   2.1 |   7.2  45.0  270   4  2   5.4   2.9
 10250   6.2  43.2  215  11  6   4.5   2.4 |   7.5  45.5  255   4  2   5.3   2.9
 10000   6.5  43.7  210  11  6   5.0   2.8 |   7.9  46.2  240   4  2   5.3   2.9
  9750   7.1  44.8  200  12  6   3.1   1.7 |   8.6  47.5  215   6  3   3.9   2.1
  9500   7.4  45.3  195  12  6   3.8   2.1 |   8.9  48.0  210   6  3   4.3   2.3
  9250   7.6  45.7  195  12  6   4.2   2.3 |   9.2  48.6  205   7  4   4.5   2.5
  9000   7.9  46.2  190  12  6   3.2   1.7 |   9.5  49.1  200   8  4   3.8   2.1
  8750   8.1  46.6  185  12  6   4.6   2.5 |   9.7  49.5  195   9  5   5.1   2.8
  8500   8.6  47.5  185  12  6   7.3   4.0 |  10.2  50.4  190   9  5   8.0   4.4
  8250   9.1  48.4  180  11  6   7.5   4.1 |  10.8  51.4  185   9  5   8.3   4.5
  8000   9.6  49.3  175  11  6   6.5   3.6 |  11.3  52.3  180   9  5   8.6   4.7
  7750  10.1  50.2  175  11  6  10.2   5.6 |  12.1  53.8  175   9  5  14.6   8.0
  7500  11.1  52.0  170  10  5  19.0  10.4 |  13.5  56.3  175   9  4  23.3  12.8
  7250  12.2  54.0  165   9  4   2.7   1.5 |  14.9  58.8  170   8  4   8.4   4.6
  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

           07/31/2014 at 1500 MDT          |       07/31/2014 at 1800 MDT
                                           |
K index... +25.2  LI... -1.9               | K index... +23.8  LI... -2.0
CAPE... +323.4  CIN... -0.3                | CAPE... +203.1  CIN... -0.7
                                           |
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 -63.0 -81.4  300  31 16   2.9   1.6 | -63.4 -82.1  300  35 18   3.0   1.7
 45000 -58.7 -73.7  295  54 28   2.8   1.5 | -59.0 -74.2  295  55 28   2.7   1.5
 40000 -53.2 -63.8  290  74 38   7.5   4.1 | -53.5 -64.3  285  70 36   8.2   4.5
 38000 -48.7 -55.7  290  64 33   7.5   4.1 | -48.6 -55.5  285  64 33   8.2   4.5
 36000 -44.2 -47.6  290  55 28   7.6   4.2 | -43.7 -46.7  280  58 30   8.2   4.5
 34000 -39.4 -38.9  290  48 25   8.1   4.4 | -38.8 -37.8  285  52 27   8.2   4.5
 32000 -34.5 -30.1  295  42 22   8.0   4.4 | -33.9 -29.0  290  46 24   8.1   4.4
 30000 -29.7 -21.5  295  36 19   8.1   4.4 | -29.5 -21.1  290  39 20   7.4   4.0
 29000 -27.2 -17.0  295  34 17   8.1   4.4 | -27.3 -17.1  295  36 19   7.4   4.0
 28000 -24.8 -12.6  295  31 16   7.4   4.1 | -25.1 -13.2  295  33 17   7.3   4.0
 27000 -22.8  -9.0  300  30 15   7.0   3.8 | -22.9  -9.2  300  31 16   7.3   4.0
 26000 -20.2  -4.4  300  28 14   7.1   3.9 | -20.7  -5.3  305  28 14   7.3   4.0
 25000 -18.1  -0.6  305  27 14   7.0   3.8 | -18.0  -0.4  310  25 13   6.9   3.8
 24000 -16.2   2.8  310  25 13   6.9   3.8 | -16.0   3.2  310  24 12   6.7   3.7
 23000 -14.2   6.4  310  24 12   6.9   3.8 | -14.1   6.6  315  22 12   6.7   3.7
 22000 -12.2  10.0  315  22 11   6.7   3.7 | -12.2  10.0  315  21 11   6.3   3.4
 21000 -10.3  13.5  315  20 10   6.5   3.6 | -10.5  13.1  315  18  9   6.0   3.3
 20000  -8.4  16.9  320  17  9   6.6   3.6 |  -8.8  16.2  320  14  7   6.0   3.3
 19500  -7.5  18.5  320  16  8   6.5   3.6 |  -7.9  17.8  320  13  7   6.1   3.3
 19000  -6.6  20.1  325  15  8   6.0   3.3 |  -7.0  19.4  325  11  5   6.5   3.5
 18500  -5.7  21.7  330  13  7   6.0   3.3 |  -6.1  21.0  330   9  4   6.4   3.5
 18000  -4.8  23.4  335  12  6   5.8   3.2 |  -5.2  22.6  340   7  4   6.2   3.4
 17500  -4.0  24.8  335  11  6   5.7   3.1 |  -4.2  24.4  355   6  3   6.0   3.3
 17000  -3.1  26.4  340  10  5   5.6   3.1 |  -3.3  26.1  010   5  3   5.9   3.2
 16500  -2.3  27.9  345   9  5   5.0   2.8 |  -2.6  27.3  020   5  3   4.5   2.4
 16000  -1.6  29.1  345   8  4   5.0   2.8 |  -1.9  28.6  030   5  3   4.4   2.4
 15500  -0.8  30.6  350   8  4   5.7   3.2 |  -1.1  30.0  035   5  3   6.2   3.4
 15000   0.0  32.0  360   7  4   5.8   3.2 |  -0.2  31.6  045   5  3   6.4   3.5
 14500   0.8  33.4  005   6  3   6.0   3.3 |   0.8  33.4  055   5  3   6.5   3.6
 14000   1.7  35.1  015   6  3   6.2   3.4 |   1.7  35.1  060   5  3   6.6   3.6
 13500   2.6  36.7  025   5  3   6.1   3.4 |   2.6  36.7  070   6  3   6.5   3.6
 13000   3.4  38.1  030   5  3   6.0   3.3 |   3.5  38.3  070   6  3   6.4   3.5
 12500   4.3  39.7  035   5  2   6.0   3.3 |   4.4  39.9  075   6  3   6.0   3.3
 12000   5.2  41.4  040   5  2   6.4   3.5 |   5.3  41.5  075   5  3   6.3   3.4
 11750   5.6  42.1  040   5  2   6.4   3.5 |   5.7  42.3  075   5  3   6.3   3.5
 11500   6.1  43.0  040   5  2   6.4   3.5 |   6.1  43.0  075   5  3   6.3   3.5
 11250   6.5  43.7  045   4  2   6.2   3.4 |   6.6  43.9  070   5  3   6.7   3.7
 11000   7.0  44.6  045   4  2   6.2   3.4 |   7.1  44.8  065   5  3   6.7   3.7
 10750   7.4  45.3  040   4  2   6.3   3.4 |   7.5  45.5  060   5  3   6.4   3.5
 10500   7.8  46.0  035   3  2   6.3   3.5 |   7.9  46.2  055   5  3   6.7   3.7
 10250   8.3  46.9  035   3  2   6.7   3.7 |   8.4  47.1  050   5  2   7.5   4.1
 10000   9.2  48.6  035   2  1   6.3   3.5 |   9.5  49.1  045   4  2   7.3   4.0
  9750   9.6  49.3  045   1  0   6.5   3.6 |   9.9  49.8  045   4  2   7.7   4.2
  9500  10.1  50.2  000   0  0   8.3   4.5 |  10.5  50.9  040   4  2   9.5   5.2
  9250  10.7  51.3  145   1  0   9.2   5.1 |  11.3  52.3  045   4  2  10.5   5.7
  9000  11.3  52.3  160   1  0   8.1   4.5 |  12.0  53.6  045   4  2   9.4   5.2
  8750  11.9  53.4  165   1  1   8.5   4.7 |  12.6  54.7  045   4  2   9.0   4.9
  8500  12.6  54.7  165   1  1  10.4   5.7 |  13.3  55.9  045   4  2   9.8   5.4
  8250  13.4  56.1  165   2  1  11.3   6.2 |  14.1  57.4  045   3  2  10.1   5.5
  8000  14.2  57.6  165   2  1   9.6   5.3 |  14.8  58.6  045   3  2   9.9   5.4
  7750  14.9  58.8  165   2  1  12.6   6.9 |  15.5  59.9  050   3  2  10.9   6.0
  7500  16.1  61.0  160   2  1  22.2  12.2 |  16.4  61.5  050   3  1  12.8   7.0
  7250  17.4  63.3  155   2  1   4.3   2.4 |  17.2  63.0  050   3  1   9.4   5.2
  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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