Soaring Guidance
Issued by NWS Pueblo, CO

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800
UXUS97 KPUB 221237
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0637 MDT Thursday, September 22, 2016

This forecast is for Thursday, September 22, 2016:

If the trigger temperature of 72.4 F/22.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 647 ft/min (3.3 m/s)
   Maximum height of thermals.................. 16023 ft MSL (9265 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11706 ft MSL (4948 ft AGL)
Thermal soaring outlook for Friday 09/23....... Good

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

Remarks...

Sunrise/Sunset.................... 06:47:11 / 18:56:40 MDT
Total possible sunshine........... 12 hr 9 min 29 sec (729 min 29 sec)
Altitude of sun at 12:51:26 MDT... 50.98 degrees

Upper air data from numerical model forecast valid on 09/22/2016 at 0600 MDT

Freezing level.................. 15811 ft MSL (9053 ft AGL)
Convective condensation level... 15191 ft MSL (8433 ft AGL)
Lifted condensation level....... 15168 ft MSL (8410 ft AGL)
Lifted index.................... -1.9
K index......................... +18.2

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  -67.0 -88.6   245   38   19   2.6   1.4      M     M       M      M    M
 45000  -61.7 -79.1   255   47   24   5.8   3.2      M     M       M      M    M
 40000  -52.4 -62.3   265   46   24   6.9   3.8      M     M       M      M    M
 38000  -48.2 -54.8   255   42   21   6.9   3.8      M     M       M      M    M
 36000  -44.1 -47.4   245   39   20   6.8   3.7      M     M       M      M    M
 34000  -39.1 -38.4   245   38   20   8.4   4.6      M     M       M      M    M
 32000  -34.1 -29.4   245   38   20   8.3   4.5      M     M       M      M    M
 30000  -29.5 -21.1   245   35   18   7.5   4.1   41.0 105.8    11.5      M    M
 29000  -27.3 -17.1   245   33   17   7.5   4.1   40.2 104.4    11.0      M    M
 28000  -24.5 -12.1   245   31   16   7.4   4.0   39.3 102.7    10.4      M    M
 27000  -22.3  -8.1   240   30   15   7.4   4.0   38.3 100.9     9.7      M    M
 26000  -20.1  -4.2   240   29   15   7.4   4.0   37.4  99.3     9.1      M    M
 25000  -17.9  -0.2   240   28   14   7.2   4.0   36.6  97.9     8.6      M    M
 24000  -15.9   3.4   235   26   13   6.6   3.6   35.4  95.8     7.6      M    M
 23000  -14.0   6.8   235   24   13   6.7   3.7   34.3  93.8     6.7      M    M
 22000  -12.1  10.2   235   23   12   6.7   3.7   33.4  92.1     5.8      M    M
 21000  -10.2  13.6   230   21   11   6.3   3.5   32.1  89.8     4.8      M    M
 20000   -8.3  17.1   230   19   10   6.3   3.5   30.9  87.7     3.8      M    M
 19500   -7.4  18.7   235   18    9   6.3   3.4   30.4  86.7     3.4      M    M
 19000   -6.4  20.5   235   17    9   6.7   3.6   29.9  85.7     2.9      M    M
 18500   -5.4  22.3   235   17    9   6.7   3.7   29.3  84.8     2.5      M    M
 18000   -4.4  24.1   240   17    9   6.6   3.6   28.8  83.9     2.1      M    M
 17500   -3.4  25.9   245   17    9   6.5   3.6   28.3  82.9     1.6      M    M
 17000   -2.5  27.5   245   17    9   6.5   3.6   27.7  81.9     1.1      M    M
 16500   -1.5  29.3   250   17    9   6.8   3.7   27.2  81.0     0.6      M    M
 16000   -0.6  30.9   250   17    9   6.8   3.8   26.7  80.1     0.1      M    M
 15500    0.4  32.7   255   16    8   7.1   3.9   26.2  79.2    -0.4    809  4.1
 15000    1.5  34.7   255   16    8   7.5   4.1   25.9  78.5    -0.8    763  3.9
 14500    2.5  36.5   255   15    8   7.5   4.1   25.5  77.9    -1.2    716  3.6
 14000    4.1  39.4   250   13    7   7.9   4.3   25.0  77.0    -1.8    646  3.3
 13500    5.2  41.4   245   11    6   8.4   4.6   24.7  76.5    -2.2    599  3.0
 13000    6.5  43.7   245   12    6   8.8   4.9   24.6  76.2    -2.4    544  2.8
 12500    7.9  46.2   245   14    7   7.5   4.1   24.5  76.0    -2.5    490  2.5
 12000    8.9  48.0   245   15    7   8.9   4.9   24.1  75.4    -2.9    443  2.2
 11750    9.6  49.3   245   15    8   8.4   4.6   24.0  75.2    -3.0    417  2.1
 11500   10.2  50.4   245   15    8   8.8   4.8   23.9  75.1    -3.1    391  2.0
 11250   10.8  51.4   245   16    8   8.3   4.5   23.9  74.9    -3.2    364  1.8
 11000   11.4  52.5   245   16    8   7.4   4.1   23.7  74.6    -3.4    340  1.7
 10750   11.9  53.4   250   16    8   7.6   4.2   23.5  74.3    -3.6    316  1.6
 10500   12.5  54.5   250   16    8   7.4   4.1   23.4  74.0    -3.8    292  1.5
 10250   13.0  55.4   250   16    8   6.1   3.3   23.1  73.6    -4.0    270  1.4
 10000   13.4  56.1   250   15    8   6.9   3.8   22.8  73.1    -4.3    250  1.3
  9750   14.0  57.2   250   15    8   8.3   4.5   22.7  72.9    -4.5    226  1.1
  9500   14.5  58.1   250   15    7   7.6   4.1   22.6  72.6    -4.7    202  1.0
  9250   15.0  59.0   250   14    7   6.5   3.6   22.4  72.3    -4.9    179  0.9
  9000   15.4  59.7   250   13    7   5.9   3.2   22.1  71.7    -5.2    159  0.8
  8750   15.9  60.6   250   13    7   7.2   4.0   21.8  71.3    -5.5    138  0.7
  8500   16.3  61.3   250   13    7   4.9   2.7   21.6  70.9    -5.8    117  0.6
  8250   16.5  61.7   250   13    7   0.7   0.4   21.0  69.9    -6.4    106  0.5
  8000   16.4  61.5   255   13    6  -1.9  -1.1   20.3  68.5    -7.3    101  0.5
  7750   16.3  61.3   255   12    6   4.7   2.6   19.5  67.1    -8.1     97  0.5
  7500   16.5  61.7   260   11    6  -7.1  -3.9   19.1  66.3    -8.7     84  0.4
  7250   14.9  58.8   265   10    5 -27.5 -15.1   17.1  62.9   -10.6    123  0.6
  7000   13.2  55.8   275    8    4 -16.4  -9.0   15.1  59.1   -12.6    168  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/22/2016 at 0900 MDT          |       09/22/2016 at 1200 MDT
                                           |
K index... +16.2  LI... +272.2             | K index... +25.3  LI... +271.0
CAPE... +20.0  CIN... -100.6               | CAPE... +173.0  CIN... -28.6
                                           |
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 -67.6 -89.7  245  37 19   2.8   1.5 | -68.0 -90.4  240  37 19   2.8   1.5
 45000 -61.8 -79.2  260  45 23   6.7   3.7 | -62.0 -79.6  250  42 22   6.9   3.8
 40000 -51.4 -60.5  265  49 25   6.1   3.3 | -51.1 -60.0  255  47 24   6.7   3.7
 38000 -47.7 -53.9  255  43 22   6.1   3.3 | -47.1 -52.8  250  44 22   6.7   3.7
 36000 -44.1 -47.4  245  39 20   5.9   3.3 | -43.1 -45.6  240  42 21   6.6   3.6
 34000 -39.3 -38.7  240  38 19   8.3   4.6 | -38.6 -37.5  240  39 20   7.6   4.2
 32000 -34.3 -29.7  240  37 19   8.3   4.5 | -34.0 -29.2  240  36 19   7.6   4.1
 30000 -29.6 -21.3  245  34 17   7.6   4.2 | -29.4 -20.9  240  32 17   7.8   4.3
 29000 -27.4 -17.3  245  32 16   7.6   4.2 | -27.1 -16.8  240  30 16   7.8   4.3
 28000 -24.5 -12.1  245  29 15   8.2   4.5 | -24.1 -11.4  240  28 15   8.6   4.7
 27000 -22.0  -7.6  245  29 15   8.3   4.5 | -21.5  -6.7  240  27 14   8.6   4.7
 26000 -19.6  -3.3  245  28 14   8.3   4.5 | -19.0  -2.2  235  27 14   8.6   4.7
 25000 -17.1   1.2  240  27 14   7.8   4.3 | -16.4   2.5  235  26 13   8.3   4.5
 24000 -15.3   4.5  235  27 14   5.8   3.2 | -14.4   6.1  225  26 14   6.2   3.4
 23000 -13.7   7.3  225  28 14   5.9   3.2 | -12.6   9.3  220  27 14   6.3   3.5
 22000 -12.0  10.4  220  29 15   5.9   3.3 | -10.8  12.6  210  29 15   6.2   3.4
 21000 -10.4  13.3  220  28 14   5.6   3.0 |  -9.5  14.9  210  30 16   4.3   2.4
 20000  -8.8  16.2  220  27 14   5.6   3.1 |  -8.3  17.1  210  31 16   4.4   2.4
 19500  -7.9  17.8  220  26 13   5.5   3.0 |  -7.7  18.1  205  32 16   4.4   2.4
 19000  -7.1  19.2  220  25 13   6.3   3.4 |  -7.0  19.4  205  32 16   5.6   3.1
 18500  -6.1  21.0  225  23 12   6.4   3.5 |  -6.2  20.8  205  30 16   5.8   3.2
 18000  -5.1  22.8  225  22 11   6.5   3.6 |  -5.4  22.3  205  29 15   5.8   3.2
 17500  -4.0  24.8  230  21 11   6.9   3.8 |  -4.5  23.9  205  28 14   6.0   3.3
 17000  -3.0  26.6  230  19 10   6.9   3.8 |  -3.7  25.3  200  27 14   5.9   3.2
 16500  -2.0  28.4  230  18  9   7.1   3.9 |  -2.7  27.1  200  26 13   7.3   4.0
 16000  -1.0  30.2  235  17  9   7.2   3.9 |  -1.6  29.1  200  25 13   7.5   4.1
 15500   0.0  32.0  235  15  8   7.4   4.1 |  -0.5  31.1  200  24 12   7.6   4.1
 15000   1.1  34.0  235  14  7   7.6   4.2 |   0.6  33.1  200  23 12   7.7   4.2
 14500   2.2  36.0  230  13  7   7.7   4.2 |   1.7  35.1  205  22 11   7.7   4.2
 14000   3.9  39.0  230  12  6   8.1   4.5 |   3.4  38.1  210  21 11   7.6   4.2
 13500   5.1  41.2  230  11  6   8.5   4.7 |   4.5  40.1  215  21 11   8.2   4.5
 13000   6.4  43.5  235  12  6   9.0   4.9 |   5.8  42.4  220  21 11   8.9   4.9
 12500   7.7  45.9  235  13  7   8.1   4.5 |   7.0  44.6  225  20 11   7.8   4.3
 12000   8.9  48.0  235  13  7   8.1   4.5 |   8.2  46.8  225  18  9   9.0   4.9
 11750   9.5  49.1  235  13  7   8.0   4.4 |   8.8  47.8  225  17  9   9.2   5.0
 11500  10.0  50.0  235  13  7   7.9   4.3 |   9.4  48.9  225  16  8   7.4   4.1
 11250  10.6  51.1  235  13  7   7.7   4.2 |   9.8  49.6  220  15  8   7.8   4.3
 11000  11.2  52.2  235  13  6   7.8   4.3 |  10.5  50.9  220  14  7  10.0   5.5
 10750  11.7  53.1  235  12  6   7.8   4.3 |  11.2  52.2  220  13  7   9.5   5.2
 10500  12.3  54.1  235  12  6   7.7   4.2 |  11.9  53.4  215  12  6   9.4   5.1
 10250  12.8  55.0  235  12  6   7.3   4.0 |  12.5  54.5  210  11  6   7.4   4.1
 10000  13.4  56.1  240  12  6   7.4   4.1 |  13.0  55.4  205  10  5   9.1   5.0
  9750  13.9  57.0  240  12  6   7.8   4.3 |  13.9  57.0  205  10  5  11.4   6.3
  9500  14.5  58.1  240  12  6   7.4   4.1 |  14.7  58.5  200  10  5  10.6   5.8
  9250  15.0  59.0  240  11  6   6.6   3.6 |  15.4  59.7  200  10  5   9.7   5.3
  9000  15.4  59.7  240  10  5   6.2   3.4 |  16.1  61.0  200  10  5   9.4   5.1
  8750  15.9  60.6  240  10  5   6.7   3.7 |  16.8  62.2  195  10  5  10.2   5.6
  8500  16.3  61.3  245  10  5   5.7   3.1 |  17.6  63.7  195  10  5  10.6   5.8
  8250  16.5  61.7  245   9  5   3.8   2.1 |  18.4  65.1  195  10  5  10.6   5.8
  8000  16.7  62.1  250   8  4   3.0   1.7 |  19.2  66.6  190  10  5  11.1   6.1
  7750  16.9  62.4  255   7  4   4.9   2.7 |  20.0  68.0  190  10  5   9.6   5.3
  7500  17.2  63.0  255   6  3   5.5   3.0 |  20.7  69.3  190   9  5  10.5   5.8
  7250  17.5  63.5  260   5  2   3.8   2.1 |  21.6  70.9  190   9  5  13.9   7.6
  7000  17.7  63.9  265   4  2   4.9   2.7 |  22.6  72.7  190   9  5  12.8   7.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/22/2016 at 1500 MDT          |       09/22/2016 at 1800 MDT
                                           |
K index... +12.8  LI... +271.5             | K index... +24.4  LI... +270.9
CAPE... +121.8  CIN... -35.9               | CAPE... +344.4  CIN... -18.2
                                           |
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 -68.4 -91.1  235  35 18   2.5   1.4 | -68.5 -91.3  230  32 16   2.5   1.4
 45000 -62.5 -80.5  240  40 20   7.3   4.0 | -62.6 -80.7  240  36 19   7.4   4.1
 40000 -51.0 -59.8  250  47 24   7.1   3.9 | -50.9 -59.6  240  46 24   7.6   4.2
 38000 -46.7 -52.1  240  43 22   7.1   3.9 | -46.3 -51.3  235  44 23   7.6   4.2
 36000 -42.5 -44.5  235  41 21   7.1   3.9 | -41.7 -43.1  230  43 22   7.7   4.2
 34000 -38.0 -36.4  235  38 20   7.4   4.1 | -37.5 -35.5  230  42 22   7.0   3.9
 32000 -33.6 -28.5  235  37 19   7.4   4.1 | -33.3 -27.9  230  41 21   7.0   3.8
 30000 -28.8 -19.8  235  34 17   8.0   4.4 | -28.6 -19.5  225  39 20   8.0   4.4
 29000 -26.5 -15.7  235  32 17   8.0   4.4 | -26.2 -15.2  225  38 20   8.0   4.4
 28000 -23.5 -10.3  230  30 16   8.0   4.4 | -23.8 -10.8  220  38 19   8.0   4.4
 27000 -21.1  -6.0  225  30 15   8.0   4.4 | -20.9  -5.6  220  37 19   7.8   4.3
 26000 -18.7  -1.7  225  29 15   8.0   4.4 | -18.6  -1.5  215  36 19   7.8   4.3
 25000 -16.3   2.7  220  29 15   7.8   4.3 | -16.2   2.8  215  35 18   7.7   4.2
 24000 -14.4   6.1  215  28 15   5.9   3.2 | -14.2   6.4  215  33 17   6.5   3.6
 23000 -12.7   9.1  210  28 15   5.9   3.3 | -12.3   9.9  215  31 16   6.5   3.6
 22000 -10.9  12.4  205  28 15   5.8   3.2 | -10.3  13.5  215  29 15   6.4   3.5
 21000  -9.4  15.1  210  31 16   4.7   2.6 |  -8.9  16.0  220  32 17   4.5   2.5
 20000  -8.0  17.6  215  35 18   4.7   2.6 |  -7.5  18.5  220  37 19   4.5   2.5
 19500  -7.3  18.9  220  37 19   4.7   2.6 |  -6.8  19.8  225  39 20   4.5   2.5
 19000  -6.6  20.1  220  38 20   5.3   2.9 |  -6.2  20.8  225  40 21   4.3   2.3
 18500  -5.8  21.6  220  37 19   5.5   3.0 |  -5.5  22.1  220  40 20   4.3   2.4
 18000  -5.0  23.0  225  35 18   5.7   3.1 |  -4.9  23.2  220  39 20   4.5   2.4
 17500  -4.1  24.6  225  34 18   7.0   3.8 |  -4.4  24.1  220  38 19   4.2   2.3
 17000  -3.1  26.4  225  33 17   6.9   3.8 |  -3.9  25.0  220  37 19   4.7   2.6
 16500  -2.1  28.2  230  32 17   7.2   3.9 |  -3.2  26.2  215  35 18   7.9   4.3
 16000  -1.0  30.2  230  31 16   7.3   4.0 |  -2.1  28.2  215  33 17   8.9   4.9
 15500  -0.0  32.0  230  29 15   7.7   4.2 |  -0.9  30.4  210  32 16   9.1   5.0
 15000   1.1  34.0  235  28 15   8.4   4.6 |   0.3  32.5  210  30 16   8.7   4.8
 14500   2.3  36.1  235  27 14   8.5   4.6 |   1.5  34.7  210  29 15   8.8   4.8
 14000   4.0  39.2  230  25 13   8.5   4.7 |   2.8  37.0  205  28 14   9.1   5.0
 13500   5.1  41.2  230  23 12   8.9   4.9 |   4.8  40.6  205  27 14   9.0   4.9
 13000   6.4  43.5  225  22 11   9.4   5.1 |   6.1  43.0  200  26 13   8.9   4.9
 12500   7.7  45.9  225  21 11   8.6   4.7 |   7.4  45.3  200  26 13   9.4   5.1
 12000   9.0  48.2  220  20 10   9.1   5.0 |   8.7  47.7  200  25 13   8.9   4.9
 11750   9.7  49.5  215  20 10   9.2   5.0 |   9.4  48.9  200  25 13   9.2   5.0
 11500  10.3  50.5  210  20 10   8.4   4.6 |  10.1  50.2  195  24 12   8.7   4.8
 11250  10.9  51.6  210  20 10   8.8   4.8 |  10.7  51.3  195  24 12   8.7   4.8
 11000  11.6  52.9  205  19 10  10.0   5.5 |  11.4  52.5  195  24 12   9.2   5.0
 10750  12.3  54.1  205  19 10   9.7   5.3 |  12.0  53.6  195  23 12   9.0   4.9
 10500  13.0  55.4  200  19 10   9.8   5.4 |  12.7  54.9  195  23 12   9.3   5.1
 10250  13.7  56.7  200  19 10   8.0   4.4 |  13.3  55.9  195  23 12   7.9   4.4
 10000  14.3  57.7  200  19 10   9.3   5.1 |  13.9  57.0  190  22 12   8.1   4.4
  9750  15.1  59.2  195  19 10  11.5   6.3 |  14.5  58.1  190  22 11   9.3   5.1
  9500  15.9  60.6  195  19 10  10.9   6.0 |  15.2  59.4  190  21 11   9.2   5.1
  9250  16.7  62.1  195  19 10   9.5   5.2 |  15.9  60.6  190  20 10   7.7   4.2
  9000  17.4  63.3  195  19 10   8.9   4.9 |  16.3  61.3  190  19 10   7.0   3.9
  8750  18.1  64.6  195  19 10  10.4   5.7 |  17.0  62.6  185  19 10   9.3   5.1
  8500  18.9  66.0  190  19 10  10.8   5.9 |  17.7  63.9  185  18  9   9.9   5.4
  8250  19.7  67.5  190  19 10  10.7   5.9 |  18.4  65.1  185  17  9   8.7   4.8
  8000  20.5  68.9  190  19 10  11.2   6.1 |  18.9  66.0  185  16  8   7.7   4.2
  7750  21.3  70.3  190  19 10   9.6   5.3 |  19.5  67.1  185  15  8   8.7   4.8
  7500  21.9  71.4  190  18  9   9.6   5.3 |  20.2  68.4  180  14  7   8.7   4.8
  7250  22.7  72.9  190  18  9  12.7   7.0 |  20.7  69.3  180  13  7   6.3   3.5
  7000  23.7  74.7  185  17  9  13.1   7.2 |  21.1  70.0  180  12  6   5.0   2.8
  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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