Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 051017
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0417 MDT Saturday, September 5, 2015

This forecast is for Saturday, September 5, 2015:

If the trigger temperature of 70.2 F/21.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1011 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16985 ft MSL (10227 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14123 ft MSL (7365 ft AGL)
Thermal soaring outlook for Sunday 09/06....... Good

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

Remarks...

Sunrise/Sunset.................... 06:31:14 / 19:24:55 MDT
Total possible sunshine........... 12 hr 53 min 41 sec (773 min 41 sec)
Altitude of sun at 12:57:38 MDT... 57.77 degrees

Upper air data from numerical model forecast valid on 09/05/2015 at 0600 MDT

Freezing level.................. 15475 ft MSL (8717 ft AGL)
Convective condensation level... 14846 ft MSL (8088 ft AGL)
Lifted condensation level....... 15489 ft MSL (8732 ft AGL)
Lifted index.................... -1.0
K index......................... +26.6

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  -66.1 -87.0   240   49   25   3.1   1.7      M     M       M      M    M
 45000  -59.8 -75.6   245   70   36   6.3   3.5      M     M       M      M    M
 40000  -50.2 -58.4   245   80   41   6.8   3.7      M     M       M      M    M
 38000  -46.1 -51.0   245   75   39   6.8   3.7      M     M       M      M    M
 36000  -42.1 -43.8   240   70   36   6.7   3.7      M     M       M      M    M
 34000  -37.1 -34.8   235   67   34   7.4   4.1      M     M       M      M    M
 32000  -32.6 -26.7   235   64   33   8.1   4.5      M     M       M      M    M
 30000  -27.9 -18.2   230   58   30   8.1   4.4   42.4 108.4    12.2      M    M
 29000  -25.5 -13.9   230   55   28   8.1   4.4   41.8 107.3    11.8      M    M
 28000  -23.1  -9.6   230   52   27   7.2   4.0   41.3 106.3    11.5      M    M
 27000  -21.1  -6.0   230   49   25   6.9   3.8   40.1 104.2    10.6      M    M
 26000  -19.0  -2.2   230   46   24   6.9   3.8   39.0 102.3     9.9      M    M
 25000  -17.0   1.4   230   43   22   7.0   3.8   38.1 100.6     9.2      M    M
 24000  -15.1   4.8   225   40   21   6.8   3.7   37.0  98.6     8.3      M    M
 23000  -13.0   8.6   225   38   20   6.8   3.7   35.9  96.6     7.4      M    M
 22000  -11.0  12.2   225   36   19   6.8   3.7   35.0  94.9     6.6      M    M
 21000   -9.2  15.4   225   34   18   5.7   3.1   33.6  92.4     5.5      M    M
 20000   -7.6  18.3   225   32   17   5.7   3.1   32.2  89.9     4.2      M    M
 19500   -6.8  19.8   225   31   16   5.8   3.2   31.5  88.7     3.7      M    M
 19000   -5.9  21.4   225   30   16   5.4   3.0   30.8  87.5     3.1      M    M
 18500   -5.2  22.6   225   29   15   5.4   2.9   30.1  86.1     2.4      M    M
 18000   -4.4  24.1   225   28   14   5.4   2.9   29.3  84.8     1.7      M    M
 17500   -3.7  25.3   225   27   14   5.1   2.8   28.6  83.4     0.9      M    M
 17000   -3.0  26.6   230   26   13   5.1   2.8   27.8  82.0     0.2      M    M
 16500   -2.2  28.0   230   24   12   6.2   3.4   27.1  80.7    -0.5    883  4.5
 16000   -0.8  30.6   230   21   11   6.6   3.6   26.3  79.3    -1.3    818  4.2
 15500    0.2  32.4   235   19   10   6.6   3.6   25.8  78.4    -1.8    774  3.9
 15000    1.1  34.0   235   18    9   6.6   3.6   25.3  77.5    -2.3    731  3.7
 14500    2.1  35.8   240   17    9   7.1   3.9   24.8  76.6    -2.8    687  3.5
 14000    3.2  37.8   245   15    8   7.5   4.1   24.4  75.9    -3.2    639  3.2
 13500    4.3  39.7   245   14    7   7.6   4.2   24.0  75.3    -3.5    590  3.0
 13000    5.5  41.9   250   13    7   7.8   4.3   23.7  74.7    -3.8    541  2.7
 12500    6.6  43.9   255   12    6   7.1   3.9   23.4  74.2    -4.2    491  2.5
 12000    7.8  46.0   260   11    5   8.4   4.6   23.1  73.5    -4.5    443  2.3
 11750    8.4  47.1   265   10    5   8.2   4.5   22.9  73.3    -4.7    417  2.1
 11500    9.0  48.2   265    9    5   7.8   4.3   22.8  73.1    -4.8    392  2.0
 11250    9.5  49.1   270    9    5   7.5   4.1   22.7  72.8    -5.0    368  1.9
 11000   10.1  50.2   275    9    5   8.0   4.4   22.5  72.5    -5.1    343  1.7
 10750   10.7  51.3   275   10    5   8.2   4.5   22.4  72.3    -5.3    317  1.6
 10500   11.3  52.3   280   10    5   8.2   4.5   22.2  72.0    -5.4    291  1.5
 10250   11.9  53.4   280   11    5   7.8   4.3   22.1  71.8    -5.5    266  1.4
 10000   12.5  54.5   285   11    6   8.4   4.6   22.0  71.6    -5.7    241  1.2
  9750   13.2  55.8   285   12    6   9.2   5.0   21.9  71.5    -5.8    214  1.1
  9500   13.8  56.8   285   13    7   8.9   4.9   21.9  71.4    -5.9    187  0.9
  9250   14.4  57.9   290   14    7   7.6   4.2   21.8  71.2    -6.0    161  0.8
  9000   14.9  58.8   285   15    7   6.9   3.8   21.6  70.8    -6.2    139  0.7
  8750   15.5  59.9   285   16    8   8.5   4.7   21.4  70.5    -6.4    115  0.6
  8500   16.1  61.0   285   17    9   7.2   3.9   21.3  70.3    -6.6     89  0.5
  8250   16.4  61.5   280   17    9   2.4   1.3   20.9  69.6    -7.0     72  0.4
  8000   16.4  61.5   280   16    8  -1.1  -0.6   20.2  68.4    -7.8     66  0.3
  7750   16.4  61.5   275   16    8   4.9   2.7   19.5  67.1    -8.6     59  0.3
  7500   16.7  62.1   265   14    7   0.2   0.1   19.2  66.6    -9.0     41  0.2
  7250   16.0  60.8   260   11    6 -14.0  -7.7   18.2  64.7   -10.1     55  0.3
  7000   14.9  58.8   260    8    4 -11.0  -6.0   16.9  62.3   -11.5     80  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/05/2015 at 0900 MDT          |       09/05/2015 at 1200 MDT
                                           |
K index... +26.9  LI... +272.9             | K index... +26.5  LI... +272.8
CAPE... 0.0  CIN... -25.1                  | CAPE... +12.7  CIN... -4.6
                                           |
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 -66.0 -86.8  225  51 26   2.4   1.3 | -66.5 -87.7  220  53 27   2.6   1.4
 45000 -60.3 -76.5  235  69 36   6.6   3.6 | -60.6 -77.1  225  71 37   6.6   3.6
 40000 -50.3 -58.5  240  75 39   6.8   3.8 | -50.5 -58.9  235  79 41   7.0   3.8
 38000 -46.2 -51.2  235  74 38   6.8   3.8 | -46.3 -51.3  230  77 40   7.0   3.8
 36000 -42.0 -43.6  235  74 38   6.8   3.8 | -42.1 -43.8  230  75 39   7.0   3.8
 34000 -37.4 -35.3  230  71 37   6.8   3.7 | -37.2 -35.0  225  68 35   7.3   4.0
 32000 -33.4 -28.1  225  69 35   7.4   4.0 | -32.9 -27.2  225  61 32   8.0   4.4
 30000 -28.3 -18.9  225  66 34   8.7   4.7 | -27.8 -18.0  225  59 30   8.7   4.8
 29000 -25.8 -14.4  225  64 33   8.7   4.8 | -25.2 -13.4  225  58 30   8.7   4.8
 28000 -23.2  -9.8  225  62 32   6.8   3.7 | -22.7  -8.9  225  57 30   6.7   3.7
 27000 -21.4  -6.5  225  59 30   6.2   3.4 | -20.9  -5.6  225  54 28   6.0   3.3
 26000 -19.6  -3.3  225  55 28   6.2   3.4 | -19.1  -2.4  230  51 26   6.0   3.3
 25000 -17.8  -0.0  225  51 26   6.2   3.4 | -17.3   0.9  230  48 24   6.1   3.3
 24000 -15.7   3.7  225  47 24   7.5   4.1 | -15.4   4.3  230  44 23   6.7   3.7
 23000 -13.5   7.7  225  42 22   7.5   4.1 | -13.4   7.9  230  41 21   6.8   3.7
 22000 -11.3  11.7  220  38 19   7.4   4.1 | -11.5  11.3  230  37 19   6.8   3.7
 21000  -9.6  14.7  225  35 18   5.6   3.1 |  -9.7  14.5  230  33 17   6.3   3.4
 20000  -7.9  17.8  225  32 17   5.7   3.1 |  -7.8  18.0  235  29 15   6.3   3.5
 19500  -7.1  19.2  225  31 16   5.7   3.1 |  -6.9  19.6  235  28 14   6.3   3.5
 19000  -6.3  20.7  225  30 15   5.5   3.0 |  -6.0  21.2  235  26 13   6.1   3.4
 18500  -5.6  21.9  225  29 15   5.4   3.0 |  -5.1  22.8  240  25 13   6.1   3.3
 18000  -4.8  23.4  225  28 15   5.5   3.0 |  -4.2  24.4  240  23 12   6.0   3.3
 17500  -4.0  24.8  230  28 14   5.7   3.1 |  -3.4  25.9  240  22 12   5.3   2.9
 17000  -3.2  26.2  230  27 14   5.6   3.1 |  -2.7  27.1  240  22 11   5.4   2.9
 16500  -2.3  27.9  230  26 13   6.5   3.6 |  -1.5  29.3  245  20 10   4.9   2.7
 16000  -0.8  30.6  230  25 13   6.7   3.7 |  -0.8  30.6  245  19 10   4.9   2.7
 15500   0.2  32.4  230  23 12   7.0   3.8 |  -0.1  31.8  245  17  9   5.2   2.9
 15000   1.2  34.2  230  21 11   7.0   3.8 |   0.7  33.3  250  15  8   5.2   2.9
 14500   2.2  36.0  230  19 10   6.4   3.5 |   1.4  34.5  250  13  7   6.2   3.4
 14000   3.1  37.6  235  16  8   6.1   3.3 |   2.4  36.3  245  11  6   6.8   3.7
 13500   4.0  39.2  235  13  6   6.4   3.5 |   3.4  38.1  245   8  4   7.4   4.1
 13000   5.0  41.0  245   9  5   7.0   3.8 |   4.6  40.3  240   6  3   8.5   4.6
 12500   6.0  42.8  260   6  3   6.6   3.6 |   5.9  42.6  240   5  2   8.4   4.6
 12000   7.1  44.8  270   6  3   8.7   4.8 |   7.1  44.8  230   5  2   9.1   5.0
 11750   7.8  46.0  280   6  3   8.4   4.6 |   7.8  46.0  225   5  2   9.2   5.0
 11500   8.4  47.1  290   6  3   8.4   4.6 |   8.5  47.3  215   4  2   8.7   4.8
 11250   9.0  48.2  295   7  3   7.9   4.3 |   9.1  48.4  215   5  2   9.0   5.0
 11000   9.6  49.3  300   7  4   7.7   4.2 |   9.8  49.6  210   5  2   9.9   5.4
 10750  10.2  50.4  305   8  4   7.8   4.3 |  10.5  50.9  205   5  3   9.9   5.4
 10500  10.8  51.4  305   8  4   7.8   4.3 |  11.2  52.2  200   5  3   9.7   5.3
 10250  11.3  52.3  305   9  4   7.8   4.3 |  11.9  53.4  200   5  3   8.3   4.6
 10000  11.9  53.4  310   9  5   8.2   4.5 |  12.5  54.5  195   5  3   9.4   5.2
  9750  12.5  54.5  310   9  5   8.6   4.7 |  13.3  55.9  195   6  3  11.1   6.1
  9500  13.2  55.8  315   9  5   8.4   4.6 |  14.1  57.4  190   6  3  10.4   5.7
  9250  13.8  56.8  315   9  5   7.7   4.2 |  14.8  58.6  190   6  3   9.4   5.2
  9000  14.3  57.7  315  10  5   7.6   4.2 |  15.5  59.9  190   6  3   9.3   5.1
  8750  14.9  58.8  315  11  5   8.5   4.6 |  16.3  61.3  185   6  3  10.7   5.9
  8500  15.5  59.9  315  11  6   8.7   4.8 |  17.1  62.8  185   6  3  11.0   6.0
  8250  16.1  61.0  310  11  6   8.6   4.7 |  17.9  64.2  185   6  3  10.3   5.6
  8000  16.7  62.1  305  10  5   8.3   4.5 |  18.6  65.5  185   6  3  10.4   5.7
  7750  17.2  63.0  300  10  5   9.7   5.3 |  19.4  66.9  185   6  3   9.6   5.3
  7500  18.0  64.4  300   9  5   9.5   5.2 |  20.1  68.2  180   6  3  10.6   5.8
  7250  18.6  65.5  295   8  4   7.4   4.1 |  21.0  69.8  180   6  3  12.8   7.0
  7000  19.1  66.4  290   7  4   8.7   4.8 |  21.9  71.4  180   6  3  11.5   6.3
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/05/2015 at 1500 MDT          |       09/05/2015 at 1800 MDT
                                           |
K index... +26.6  LI... +271.8             | K index... +31.6  LI... +270.8
CAPE... +158.9  CIN... -15.6               | CAPE... +200.8  CIN... -16.2
                                           |
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 -66.2 -87.2  220  57 29   1.7   0.9 | -65.9 -86.6  225  57 29   2.0   1.1
 45000 -61.0 -77.8  225  73 38   6.9   3.8 | -60.8 -77.4  230  77 40   6.3   3.4
 40000 -50.6 -59.1  230  82 42   7.3   4.0 | -51.2 -60.2  235  87 45   7.0   3.8
 38000 -46.2 -51.2  230  81 41   7.3   4.0 | -47.0 -52.6  230  83 43   7.0   3.8
 36000 -41.8 -43.2  230  79 41   7.4   4.1 | -42.8 -45.0  230  79 41   6.8   3.7
 34000 -37.2 -35.0  230  74 38   6.7   3.7 | -37.1 -34.8  225  70 36   8.5   4.7
 32000 -33.2 -27.8  225  70 36   7.3   4.0 | -32.0 -25.6  215  62 32   9.4   5.1
 30000 -28.2 -18.8  230  61 31   8.6   4.7 | -27.7 -17.9  225  61 32   7.2   3.9
 29000 -25.6 -14.1  230  57 29   8.6   4.7 | -25.5 -13.9  230  62 32   7.2   3.9
 28000 -23.1  -9.6  230  52 27   6.8   3.7 | -23.4 -10.1  235  62 32   6.7   3.7
 27000 -21.2  -6.2  230  49 25   6.3   3.5 | -21.4  -6.5  235  57 29   6.6   3.6
 26000 -19.3  -2.7  235  46 24   6.3   3.4 | -19.4  -2.9  240  51 26   6.6   3.6
 25000 -17.4   0.7  235  43 22   6.3   3.5 | -17.4   0.7  240  46 24   6.6   3.6
 24000 -15.5   4.1  235  40 20   6.8   3.7 | -15.3   4.5  240  42 22   6.8   3.7
 23000 -13.5   7.7  230  36 18   6.9   3.8 | -13.3   8.1  235  37 19   6.8   3.7
 22000 -11.6  11.1  225  32 17   6.9   3.8 | -11.2  11.8  230  33 17   6.6   3.6
 21000  -9.7  14.5  235  32 17   6.4   3.5 |  -9.7  14.5  235  31 16   5.2   2.8
 20000  -7.8  18.0  240  33 17   6.4   3.5 |  -8.2  17.2  240  30 15   5.4   3.0
 19500  -6.8  19.8  245  34 18   6.4   3.5 |  -7.5  18.5  240  30 15   5.6   3.1
 19000  -5.9  21.4  250  34 18   6.1   3.3 |  -6.7  19.9  245  28 15   5.5   3.0
 18500  -5.0  23.0  250  32 17   6.0   3.3 |  -6.0  21.2  250  25 13   5.6   3.1
 18000  -4.2  24.4  250  30 15   6.0   3.3 |  -5.3  22.5  260  23 12   6.1   3.3
 17500  -3.3  26.1  255  27 14   5.9   3.2 |  -4.3  24.3  265  21 11   7.8   4.3
 17000  -2.5  27.5  255  24 13   5.9   3.2 |  -3.2  26.2  265  19 10   7.8   4.3
 16500  -1.6  29.1  260  22 11   5.8   3.2 |  -2.1  28.2  270  17  9   8.6   4.7
 16000  -0.4  31.3  260  18  9   5.7   3.1 |  -0.3  31.5  265  15  8   8.8   4.8
 15500   0.5  32.9  265  16  8   6.8   3.7 |   1.0  33.8  265  14  7   8.1   4.4
 15000   1.4  34.5  265  14  7   6.8   3.7 |   2.1  35.8  260  14  7   8.1   4.5
 14500   2.4  36.3  265  12  6   7.7   4.2 |   3.3  37.9  260  13  7   9.0   4.9
 14000   3.5  38.3  260  11  6   8.2   4.5 |   4.7  40.5  255  12  6   9.3   5.1
 13500   4.7  40.5  255  10  5   8.8   4.8 |   6.1  43.0  250  12  6   9.3   5.1
 13000   6.1  43.0  250   9  5   9.5   5.2 |   7.5  45.5  245  12  6   9.2   5.0
 12500   7.4  45.3  240   9  5   8.7   4.8 |   8.8  47.8  235  13  7   7.9   4.3
 12000   8.7  47.7  235   9  4   9.3   5.1 |  10.0  50.0  230  13  7   9.0   4.9
 11750   9.4  48.9  230   9  4   9.9   5.4 |  10.7  51.3  230  14  7   9.2   5.0
 11500  10.1  50.2  220   9  4   6.9   3.8 |  11.3  52.3  225  14  7   7.3   4.0
 11250  10.5  50.9  215  10  5   7.2   4.0 |  11.8  53.2  225  15  8   7.4   4.1
 11000  11.3  52.3  210  10  5  10.5   5.8 |  12.5  54.5  220  15  8   9.5   5.2
 10750  12.0  53.6  205  10  5   9.7   5.3 |  13.2  55.8  215  16  8   9.0   4.9
 10500  12.7  54.9  195  10  5   9.7   5.3 |  13.8  56.8  210  16  8   8.8   4.8
 10250  13.4  56.1  195  11  6   7.7   4.2 |  14.4  57.9  210  17  9   5.4   3.0
 10000  13.9  57.0  190  11  6   9.1   5.0 |  14.8  58.6  205  17  9   7.2   3.9
  9750  14.7  58.5  190  11  6  11.2   6.2 |  15.5  59.9  200  17  9  10.5   5.8
  9500  15.5  59.9  190  11  6  10.5   5.8 |  16.2  61.2  200  18  9   9.4   5.2
  9250  16.3  61.3  185  11  6   9.7   5.3 |  16.9  62.4  195  18  9   8.3   4.6
  9000  17.0  62.6  185  11  6   9.6   5.3 |  17.5  63.5  195  18  9   8.1   4.4
  8750  17.7  63.9  185  12  6  10.8   5.9 |  18.1  64.6  190  18  9  10.0   5.5
  8500  18.6  65.5  185  12  6  11.0   6.0 |  18.9  66.0  190  18  9  10.5   5.7
  8250  19.4  66.9  185  12  6  10.3   5.7 |  19.6  67.3  185  18  9   9.9   5.4
  8000  20.1  68.2  180  12  6  10.6   5.8 |  20.4  68.7  185  17  9  10.0   5.5
  7750  20.9  69.6  180  12  6   9.1   5.0 |  21.1  70.0  185  17  9   9.2   5.1
  7500  21.5  70.7  180  12  6  10.2   5.6 |  21.7  71.1  180  16  8   7.3   4.0
  7250  22.4  72.3  180  11  6  13.6   7.5 |  22.2  72.0  180  15  8   6.1   3.4
  7000  23.4  74.1  180  11  6  12.5   6.8 |  22.6  72.7  180  14  7   6.1   3.3
  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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