Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 161248
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0648 MDT Tuesday, May 16, 2017

This forecast is for Tuesday, May 16, 2017:

If the trigger temperature of 59.8 F/15.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1533 ft/min (7.8 m/s)
   Maximum height of thermals.................. 22850 ft MSL (15246 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 0845 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15988 ft MSL (8383 ft AGL)
Thermal soaring outlook for Wednesday 05/17.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:45:12 / 20:06:08 MDT
Total possible sunshine........... 14 hr 20 min 55 sec (860 min 55 sec)
Altitude of sun at 12:55:40 MDT... 70.26 degrees

Upper air data from numerical model forecast valid on 05/16/2017 at 0600 MDT

Freezing level.................. 12961 ft MSL (5357 ft AGL)
Convective condensation level... 19981 ft MSL (12377 ft AGL)
Lifted condensation level....... 20753 ft MSL (13149 ft AGL)
Lifted index.................... -1.1
K index......................... -12.5

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  -58.7 -73.7   215   26   14   3.0   1.7      M     M       M      M    M
 45000  -54.3 -65.7   210   31   16   0.6   0.3      M     M       M      M    M
 40000  -52.9 -63.2   215   34   17   0.9   0.5      M     M       M      M    M
 38000  -52.4 -62.3   220   35   18   0.9   0.5      M     M       M      M    M
 36000  -51.9 -61.4   220   36   19   0.9   0.5      M     M       M      M    M
 34000  -50.4 -58.7   225   37   19   6.5   3.6      M     M       M      M    M
 32000  -46.4 -51.5   220   36   19   6.7   3.7      M     M       M      M    M
 30000  -42.1 -43.8   220   35   18   8.3   4.5   26.1  79.0     3.9      M    M
 29000  -39.6 -39.3   220   34   17   8.3   4.6   25.5  77.8     3.4      M    M
 28000  -37.1 -34.8   220   32   17   8.3   4.6   25.0  76.9     3.1      M    M
 27000  -34.6 -30.3   220   31   16   7.9   4.3   24.6  76.2     2.8      M    M
 26000  -32.3 -26.1   220   30   15   7.6   4.2   23.6  74.5     2.0      M    M
 25000  -30.0 -22.0   215   29   15   7.6   4.2   22.8  73.1     1.4      M    M
 24000  -27.8 -18.0   215   27   14   7.6   4.2   22.2  71.9     0.9      M    M
 23000  -24.8 -12.6   215   25   13   7.8   4.3   21.2  70.1     0.0      M    M
 22000  -22.5  -8.5   215   24   12   7.8   4.3   20.5  68.9    -0.6   1437  7.3
 21000  -20.1  -4.2   215   22   11   8.7   4.8   19.9  67.8    -1.1   1336  6.8
 20000  -17.5   0.5   210   19   10   8.6   4.7   19.5  67.0    -1.5   1229  6.2
 19500  -16.2   2.8   205   17    9   8.6   4.7   19.3  66.7    -1.6   1175  6.0
 19000  -15.0   5.0   205   16    8   8.6   4.7   19.1  66.4    -1.8   1122  5.7
 18500  -13.6   7.5   200   15    8   9.0   4.9   19.0  66.1    -1.9   1067  5.4
 18000  -12.3   9.9   200   15    8   9.0   5.0   18.8  65.9    -2.1   1012  5.1
 17500  -10.9  12.4   205   15    8   8.7   4.8   18.7  65.7    -2.2    956  4.9
 17000   -9.7  14.5   205   15    8   8.0   4.4   18.5  65.2    -2.4    904  4.6
 16500   -8.5  16.7   205   15    8   8.1   4.4   18.2  64.7    -2.7    854  4.3
 16000   -7.3  18.9   210   15    8   7.9   4.3   17.9  64.2    -3.0    804  4.1
 15500   -6.2  20.8   215   15    8   7.9   4.3   17.6  63.6    -3.3    754  3.8
 15000   -5.0  23.0   215   15    8   7.6   4.2   17.3  63.1    -3.6    704  3.6
 14500   -3.9  25.0   220   15    8   7.5   4.1   16.9  62.4    -4.1    657  3.3
 14000   -2.8  27.0   220   15    8   8.1   4.4   16.5  61.8    -4.5    610  3.1
 13500   -1.5  29.3   220   14    7   9.0   4.9   16.4  61.5    -4.7    557  2.8
 13000   -0.2  31.6   215   13    7  11.4   6.2   16.2  61.2    -4.9    503  2.6
 12500    1.2  34.2   220   12    6   6.6   3.6   16.2  61.2    -4.9    444  2.3
 12000    2.3  36.1   220   11    5   7.5   4.1   15.9  60.6    -5.3    397  2.0
 11750    2.9  37.2   225   10    5   9.3   5.1   15.8  60.4    -5.4    371  1.9
 11500    3.6  38.5   230   11    6   8.9   4.9   15.7  60.3    -5.4    342  1.7
 11250    4.2  39.6   235   11    6   7.5   4.1   15.6  60.1    -5.6    317  1.6
 11000    4.8  40.6   240   11    6   7.9   4.3   15.4  59.8    -5.8    292  1.5
 10750    5.4  41.7   240   12    6   7.8   4.3   15.3  59.5    -5.9    267  1.4
 10500    6.0  42.8   240   12    6   8.0   4.4   15.1  59.2    -6.1    242  1.2
 10250    6.6  43.9   245   12    6   8.8   4.9   15.0  59.1    -6.2    216  1.1
 10000    7.3  45.1   240   12    6   9.1   5.0   15.0  59.0    -6.3    189  1.0
  9750    7.9  46.2   245   11    6   6.4   3.5   14.9  58.7    -6.5    164  0.8
  9500    8.2  46.8   250   12    6   4.7   2.6   14.5  58.1    -6.9    145  0.7
  9250    8.6  47.5   255   12    6   5.0   2.8   14.1  57.4    -7.2    127  0.6
  9000    8.9  48.0   260   13    6   3.7   2.0   13.7  56.7    -7.7    110  0.6
  8750    9.1  48.4   265   13    7   1.0   0.6   13.2  55.7    -8.3     97  0.5
  8500    9.1  48.4   270   13    7  -0.8  -0.4   12.4  54.4    -9.0     91  0.5
  8250    9.0  48.2   275   13    7   1.4   0.8   11.7  53.0    -9.8     84  0.4
  8000    9.1  48.4   280   13    7  -3.8  -2.1   11.0  51.8   -10.5     76  0.4
  7750    8.1  46.6   280    9    5 -20.0 -11.0    9.4  48.8   -12.2     96  0.5
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  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 * * * * * *

           05/16/2017 at 0900 MDT          |       05/16/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +2.5        | CAPE...   +13.9    LI...       +0.4
CINH...     0.0    K Index... -17.1        | CINH...    -2.3    K Index...  +4.8
                                           |
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 -57.6 -71.7  220  25 13   3.2   1.7 | -55.9 -68.6  215  20 10   2.3   1.2
 45000 -53.1 -63.6  210  32 17  -0.6  -0.3 | -52.6 -62.7  210  34 18   0.2   0.1
 40000 -53.9 -65.0  215  37 19  -0.5  -0.3 | -53.0 -63.4  210  38 20  -0.3  -0.2
 38000 -53.5 -64.3  215  38 19   1.3   0.7 | -52.9 -63.2  210  39 20   0.7   0.4
 36000 -52.7 -62.9  215  39 20   1.3   0.7 | -52.5 -62.5  205  39 20   0.7   0.4
 34000 -51.0 -59.8  215  39 20   6.7   3.7 | -51.3 -60.3  205  39 20   6.5   3.6
 32000 -46.9 -52.4  215  37 19   6.9   3.8 | -47.5 -53.5  200  38 20   6.4   3.5
 30000 -42.5 -44.5  210  36 18   8.4   4.6 | -43.4 -46.1  200  37 19   8.5   4.6
 29000 -40.0 -40.0  210  34 18   8.5   4.6 | -40.8 -41.4  200  36 18   8.5   4.7
 28000 -37.4 -35.3  210  33 17   8.5   4.6 | -38.3 -36.9  200  34 18   8.5   4.7
 27000 -34.9 -30.8  210  32 16   8.2   4.5 | -35.7 -32.3  200  33 17   8.3   4.5
 26000 -32.5 -26.5  210  30 16   8.0   4.4 | -33.3 -27.9  200  32 16   7.9   4.3
 25000 -30.1 -22.2  210  29 15   8.0   4.4 | -31.0 -23.8  200  30 16   7.9   4.3
 24000 -27.6 -17.7  205  28 14   8.0   4.4 | -28.6 -19.5  200  29 15   7.9   4.3
 23000 -24.6 -12.3  205  26 13   8.1   4.4 | -25.6 -14.1  205  27 14   7.8   4.3
 22000 -22.2  -8.0  205  24 12   8.1   4.4 | -23.3  -9.9  205  26 13   7.8   4.3
 21000 -19.8  -3.6  205  22 12   8.2   4.5 | -21.0  -5.8  205  24 13   7.4   4.0
 20000 -17.3   0.9  205  21 11   8.2   4.5 | -18.8  -1.8  205  23 12   7.4   4.1
 19500 -16.1   3.0  205  20 11   8.2   4.5 | -17.7   0.1  205  22 12   7.4   4.1
 19000 -14.9   5.2  205  20 10   8.2   4.5 | -16.6   2.1  205  22 11   7.4   4.1
 18500 -13.7   7.3  205  19 10   7.9   4.4 | -15.5   4.1  205  21 11   8.0   4.4
 18000 -12.5   9.5  205  19 10   7.9   4.3 | -14.2   6.4  210  20 10   8.2   4.5
 17500 -11.3  11.7  205  18  9   7.9   4.4 | -13.0   8.6  210  19 10   8.2   4.5
 17000 -10.1  13.8  205  18  9   8.1   4.4 | -11.8  10.8  210  17  9   7.9   4.3
 16500  -8.9  16.0  205  17  9   8.1   4.5 | -10.7  12.7  215  15  8   7.9   4.3
 16000  -7.7  18.1  205  17  9   7.5   4.1 |  -9.5  14.9  215  13  7   8.2   4.5
 15500  -6.6  20.1  205  17  9   7.5   4.1 |  -8.3  17.1  220  11  6   8.3   4.6
 15000  -5.5  22.1  210  16  8   6.6   3.6 |  -7.2  19.0  220   9  4   8.9   4.9
 14500  -4.6  23.7  210  15  8   6.1   3.3 |  -5.8  21.6  220   7  4   9.2   5.0
 14000  -3.7  25.3  215  14  7   6.2   3.4 |  -4.4  24.1  220   6  3   9.3   5.1
 13500  -2.7  27.1  215  13  7   6.7   3.7 |  -3.0  26.6  215   5  3   9.7   5.3
 13000  -1.8  28.8  215  11  6  10.9   6.0 |  -1.6  29.1  210   5  2  13.7   7.5
 12500  -0.4  31.3  220  11  6   5.2   2.8 |   0.2  32.4  200   5  2   6.9   3.8
 12000   0.5  32.9  225  10  5   6.5   3.5 |   1.4  34.5  195   5  2   8.1   4.4
 11750   1.0  33.8  225  10  5   8.7   4.7 |   2.0  35.6  190   5  2  10.0   5.5
 11500   1.7  35.1  225   9  5   9.1   5.0 |   2.8  37.0  190   5  2  10.1   5.5
 11250   2.3  36.1  230   9  5   8.1   4.4 |   3.5  38.3  185   5  2   8.8   4.8
 11000   2.9  37.2  235   9  5   8.4   4.6 |   4.2  39.6  185   5  2   9.1   5.0
 10750   3.5  38.3  235   9  4   8.1   4.4 |   4.9  40.8  185   5  2   9.5   5.2
 10500   4.1  39.4  235   8  4   8.0   4.4 |   5.6  42.1  180   5  3  10.0   5.5
 10250   4.7  40.5  235   7  4   8.5   4.7 |   6.4  43.5  180   5  3  10.1   5.5
 10000   5.3  41.5  240   7  3   8.6   4.7 |   7.1  44.8  180   5  3  10.2   5.6
  9750   6.0  42.8  240   6  3   7.6   4.2 |   7.9  46.2  180   5  3  10.1   5.6
  9500   6.5  43.7  240   6  3   6.5   3.5 |   8.7  47.7  175   5  3  10.1   5.5
  9250   7.0  44.6  245   5  3   8.2   4.5 |   9.4  48.9  175   5  3  10.2   5.6
  9000   7.7  45.9  250   5  3  10.4   5.7 |  10.2  50.4  175   5  3  10.3   5.7
  8750   8.4  47.1  250   5  3   9.9   5.4 |  11.0  51.8  175   5  3  10.6   5.8
  8500   9.1  48.4  255   5  2   9.9   5.4 |  11.8  53.2  170   5  3  11.3   6.2
  8250   9.9  49.8  255   5  2   8.9   4.9 |  12.6  54.7  170   5  3   9.6   5.3
  8000  10.6  51.1  255   5  2  11.9   6.5 |  13.3  55.9  170   5  3  13.1   7.2
  7750  11.8  53.2  255   4  2  21.9  12.0 |  14.8  58.6  170   5  3  27.8  15.3
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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

           05/16/2017 at 1500 MDT          |       05/16/2017 at 1800 MDT
                                           |
CAPE...  +267.2    LI...       -0.7        | CAPE...   +92.4    LI...       -0.7
CINH...    -5.3    K Index... +19.3        | CINH...   -67.5    K Index... +20.9
                                           |
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 -54.4 -65.9  220  18  9   2.3   1.2 | -54.4 -65.9  220  21 11   2.8   1.5
 45000 -51.0 -59.8  210  32 16   0.3   0.1 | -50.3 -58.5  210  22 11   0.7   0.4
 40000 -52.3 -62.1  210  36 19  -0.8  -0.5 | -50.9 -59.6  210  26 13  -0.4  -0.2
 38000 -52.1 -61.8  210  36 19   1.2   0.7 | -51.5 -60.7  200  25 13  -1.3  -0.7
 36000 -51.4 -60.5  205  35 18   1.2   0.7 | -52.2 -62.0  190  23 12  -1.3  -0.7
 34000 -50.4 -58.7  200  34 17   4.9   2.7 | -52.4 -62.3  180  22 11   7.7   4.2
 32000 -47.6 -53.7  200  34 17   4.6   2.5 | -48.5 -55.3  165  19 10   6.6   3.6
 30000 -44.6 -48.3  200  34 17   7.9   4.3 | -44.2 -47.6  155  17  9   9.7   5.3
 29000 -42.3 -44.1  200  33 17   7.7   4.2 | -41.4 -42.5  160  17  9   9.4   5.2
 28000 -40.0 -40.0  200  32 16   7.7   4.2 | -38.6 -37.5  160  16  8   9.4   5.2
 27000 -37.7 -35.9  205  31 16   7.7   4.2 | -35.8 -32.4  160  16  8   9.5   5.2
 26000 -35.3 -31.5  205  29 15   8.1   4.5 | -33.2 -27.8  160  14  7   8.3   4.6
 25000 -32.9 -27.2  205  26 13   8.1   4.5 | -30.1 -22.2  160  13  7   8.3   4.6
 24000 -29.8 -21.6  210  23 12   8.1   4.5 | -27.6 -17.7  160  11  6   8.0   4.4
 23000 -27.4 -17.3  215  21 11   8.1   4.5 | -25.5 -13.9  170  10  5   6.9   3.8
 22000 -25.0 -13.0  220  18  9   8.1   4.5 | -23.5 -10.3  180   8  4   6.9   3.8
 21000 -22.5  -8.5  225  16  8   8.6   4.7 | -21.4  -6.5  190   7  4   6.9   3.8
 20000 -20.0  -4.0  225  14  7   8.7   4.8 | -19.4  -2.9  210   6  3   6.8   3.7
 19500 -18.7  -1.7  230  13  7   8.7   4.8 | -18.4  -1.1  220   6  3   6.8   3.7
 19000 -17.4   0.7  230  12  6   8.7   4.8 | -17.4   0.7  230   6  3   6.8   3.8
 18500 -16.1   3.0  235  10  5   9.0   4.9 | -16.4   2.5  240   6  3   7.0   3.9
 18000 -14.8   5.4  235  10  5   9.2   5.0 | -15.3   4.5  245   6  3   7.4   4.1
 17500 -13.4   7.9  235   9  5   9.2   5.0 | -14.2   6.4  255   6  3   7.3   4.0
 17000 -12.0  10.4  235   9  5   9.4   5.1 | -13.1   8.4  260   6  3   8.4   4.6
 16500 -10.6  12.9  235   8  4   9.3   5.1 | -11.8  10.8  260   6  3   8.4   4.6
 16000  -9.2  15.4  235   8  4   9.5   5.2 | -10.6  12.9  265   6  3   8.7   4.8
 15500  -7.8  18.0  230   8  4   9.5   5.2 |  -9.3  15.3  265   6  3   9.0   4.9
 15000  -6.4  20.5  230   7  4   9.2   5.0 |  -7.9  17.8  265   6  3   9.1   5.0
 14500  -5.1  22.8  225   7  4   8.7   4.8 |  -6.6  20.1  265   6  3   9.2   5.0
 14000  -3.8  25.2  220   7  4   8.9   4.9 |  -5.2  22.6  265   6  3   8.8   4.8
 13500  -2.3  27.9  215   7  4  10.3   5.6 |  -3.6  25.5  265   5  3  12.4   6.8
 13000  -0.8  30.6  205   8  4   6.4   3.5 |  -1.8  28.8  260   5  3   9.2   5.0
 12500   0.2  32.4  200   8  4  10.4   5.7 |  -1.1  30.0  245   4  2   6.8   3.7
 12000   1.6  34.9  195   8  4   8.9   4.9 |   0.3  32.5  240   4  2   8.5   4.6
 11750   2.3  36.1  190   9  4  11.7   6.4 |   1.0  33.8  235   4  2  12.0   6.6
 11500   3.3  37.9  185   9  5  11.3   6.2 |   2.0  35.6  225   4  2  10.8   5.9
 11250   3.9  39.0  185   9  5   8.2   4.5 |   2.6  36.7  220   4  2   6.6   3.6
 11000   4.6  40.3  180   9  5   9.0   4.9 |   3.1  37.6  210   4  2   7.7   4.2
 10750   5.3  41.5  180   9  5   9.0   4.9 |   3.7  38.7  205   4  2   7.4   4.1
 10500   5.9  42.6  180   9  5   9.5   5.2 |   4.2  39.6  195   5  2   7.6   4.1
 10250   6.7  44.1  180  10  5   9.9   5.4 |   4.8  40.6  190   5  3   7.5   4.1
 10000   7.4  45.3  175  10  5  10.0   5.5 |   5.3  41.5  185   6  3   7.5   4.1
  9750   8.2  46.8  175  10  5  10.1   5.5 |   5.9  42.6  185   6  3   7.1   3.9
  9500   8.9  48.0  175  10  5  10.2   5.6 |   6.3  43.3  180   7  4   5.8   3.2
  9250   9.7  49.5  175  10  5  10.1   5.6 |   6.7  44.1  180   8  4   5.7   3.1
  9000  10.4  50.7  175  10  5   9.9   5.4 |   7.2  45.0  180   8  4   6.2   3.4
  8750  11.2  52.2  175  10  5  10.3   5.6 |   8.0  46.4  175  10  5   5.4   2.9
  8500  12.0  53.6  175  10  5  10.8   5.9 |   8.4  47.1  175  10  5   5.5   3.0
  8250  12.8  55.0  170  10  5  10.2   5.6 |   8.8  47.8  180  11  6   6.2   3.4
  8000  13.5  56.3  170  10  5  11.5   6.3 |   9.3  48.7  180  11  5  10.1   5.5
  7750  14.7  58.5  170   9  5  22.3  12.3 |  10.5  50.9  175   7  4  27.3  15.0
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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).  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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