Soaring Guidance
Issued by NWS Pueblo, CO

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Soaring Forecast
National Weather Service Pueblo, Colorado
0358 MDT Saturday, April 23, 2016

This forecast is for Saturday, April 23, 2016:

If the trigger temperature of 64.9 F/18.3 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 607 ft/min (3.1 m/s)
   Maximum height of thermals.................. 17036 ft MSL (10278 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10070 ft MSL (3312 ft AGL)
Thermal soaring outlook for Sunday 04/24....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:10:38 / 19:43:33 MDT
Total possible sunshine........... 13 hr 32 min 56 sec (812 min 56 sec)
Altitude of sun at 12:57:15 MDT... 63.91 degrees

Upper air data from numerical model forecast valid on 04/23/2016 at 0600 MDT

Freezing level.................. 13665 ft MSL (6907 ft AGL)
Convective condensation level... 16273 ft MSL (9515 ft AGL)
Lifted condensation level....... 16140 ft MSL (9383 ft AGL)
Lifted index.................... -2.5
K index......................... +15.8

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  -62.0 -79.6   280   22   11   0.6   0.3      M     M       M      M    M
 45000  -61.1 -78.0   255   27   14  -0.5  -0.3      M     M       M      M    M
 40000  -62.5 -80.5   245   49   25  -0.7  -0.4      M     M       M      M    M
 38000  -59.7 -75.5   245   46   24   6.6   3.6      M     M       M      M    M
 36000  -55.8 -68.4   245   39   20   6.6   3.6      M     M       M      M    M
 34000  -51.4 -60.5   245   33   17   8.4   4.6      M     M       M      M    M
 32000  -46.4 -51.5   245   30   16   8.4   4.6      M     M       M      M    M
 30000  -41.3 -42.3   245   27   14   8.7   4.8   28.1  82.6     5.8      M    M
 29000  -38.7 -37.7   245   26   13   8.7   4.8   27.6  81.8     5.5      M    M
 28000  -35.4 -31.7   250   25   13   8.7   4.8   27.2  81.0     5.3      M    M
 27000  -32.9 -27.2   250   23   12   8.2   4.5   26.8  80.2     5.0      M    M
 26000  -30.5 -22.9   245   20   10   8.2   4.5   26.2  79.1     4.5      M    M
 25000  -28.0 -18.4   245   17    9   8.2   4.5   25.6  78.2     4.2      M    M
 24000  -25.5 -13.9   240   16    8   8.3   4.6   25.2  77.3     3.8      M    M
 23000  -23.0  -9.4   235   17    9   8.3   4.6   24.6  76.2     3.3      M    M
 22000  -20.6  -5.1   230   18    9   8.3   4.6   24.1  75.4     3.0      M    M
 21000  -18.2  -0.8   225   19   10   7.5   4.1   23.5  74.3     2.5      M    M
 20000  -16.0   3.2   220   20   11   7.5   4.1   22.7  72.9     1.7      M    M
 19500  -14.9   5.2   220   21   11   7.6   4.2   22.3  72.2     1.4      M    M
 19000  -13.8   7.2   215   22   11   7.6   4.2   22.0  71.6     1.1      M    M
 18500  -12.6   9.3   220   23   12   8.5   4.7   21.7  71.1     0.8      M    M
 18000  -11.3  11.7   225   24   12   8.4   4.6   21.5  70.7     0.6      M    M
 17500  -10.1  13.8   230   25   13   7.8   4.3   21.3  70.3     0.5      M    M
 17000   -9.0  15.8   220   24   12   7.4   4.1   20.9  69.6     0.0      M    M
 16500   -8.0  17.6   210   24   12   7.6   4.2   20.5  68.9    -0.4    964  4.9
 16000   -6.7  19.9   205   24   12   9.4   5.2   20.3  68.6    -0.6    911  4.6
 15500   -5.3  22.5   205   24   12   9.3   5.1   20.2  68.4    -0.6    855  4.3
 15000   -4.0  24.8   200   24   12   9.0   4.9   20.2  68.3    -0.7    799  4.1
 14500   -2.6  27.3   200   22   11   9.0   4.9   20.0  68.0    -0.9    744  3.8
 14000   -0.6  30.9   200   20   10   9.2   5.0   19.8  67.7    -1.0    662  3.4
 13500    0.8  33.4   200   18    9   9.2   5.0   19.8  67.6    -1.1    606  3.1
 13000    2.1  35.8   205   17    9   9.3   5.1   19.7  67.4    -1.2    550  2.8
 12500    3.5  38.3   210   16    8   9.2   5.1   19.6  67.3    -1.3    493  2.5
 12000    4.9  40.8   220   18    9   8.6   4.7   19.5  67.1    -1.4    439  2.2
 11750    5.5  41.9   225   19   10   8.5   4.7   19.4  66.9    -1.5    413  2.1
 11500    6.1  43.0   230   21   11   8.8   4.8   19.3  66.7    -1.7    386  2.0
 11250    6.7  44.1   235   23   12   7.9   4.3   19.2  66.6    -1.7    360  1.8
 11000    7.2  45.0   240   25   13   6.6   3.6   19.0  66.2    -2.0    338  1.7
 10750    7.7  45.9   245   28   14   6.4   3.5   18.7  65.7    -2.3    317  1.6
 10500    8.2  46.8   250   30   16   6.7   3.7   18.5  65.2    -2.6    296  1.5
 10250    8.6  47.5   255   33   17   5.8   3.2   18.2  64.8    -2.8    275  1.4
 10000    9.0  48.2   255   35   18   6.6   3.6   17.9  64.2    -3.2    255  1.3
  9750    9.6  49.3   255   36   18   8.2   4.5   17.8  64.0    -3.4    232  1.2
  9500   10.1  50.2   255   36   19   7.8   4.3   17.6  63.7    -3.5    207  1.1
  9250   10.7  51.3   260   37   19   8.1   4.4   17.5  63.4    -3.7    183  0.9
  9000   11.3  52.3   260   37   19   7.9   4.4   17.3  63.2    -3.9    159  0.8
  8750   11.7  53.1   260   37   19   5.2   2.8   17.1  62.8    -4.1    137  0.7
  8500   12.0  53.6   260   36   19   4.8   2.7   16.7  62.1    -4.6    121  0.6
  8250   12.3  54.1   260   36   19   1.0   0.5   16.3  61.3    -5.0    105  0.5
  8000   12.0  53.6   260   33   17  -5.3  -2.9   15.3  59.6    -6.0    105  0.5
  7750   11.7  53.1   260   30   15  -3.6  -2.0   14.2  57.6    -7.2    109  0.6
  7500   11.5  52.7   260   25   13  -0.8  -0.4   13.3  56.0    -8.1    107  0.5
  7250   11.1  52.0   260   19   10 -13.3  -7.3   12.3  54.2    -9.1    111  0.6
  7000    9.2  48.6   265   15    8 -34.9 -19.1   10.3  50.6   -11.2    160  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/23/2016 at 0900 MDT          |       04/23/2016 at 1200 MDT
                                           |
K index... +15.2  LI... +273.5             | K index... -7.0  LI... +274.1
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.7 -77.3  275  22 11   2.0   1.1 | -59.9 -75.8  280  21 11   3.0   1.7
 45000 -58.1 -72.6  255  32 17  -3.7  -2.0 | -55.9 -68.6  255  25 13  -6.5  -3.6
 40000 -62.9 -81.2  245  52 27  -3.1  -1.7 | -64.3 -83.7  245  55 29  -5.5  -3.0
 38000 -60.5 -76.9  245  50 26   7.2   4.0 | -61.7 -79.1  240  55 28   9.0   4.9
 36000 -56.2 -69.2  245  45 23   7.2   4.0 | -56.3 -69.3  235  47 24   9.0   4.9
 34000 -51.5 -60.7  245  40 21   8.7   4.8 | -51.0 -59.8  230  41 21   8.8   4.8
 32000 -46.3 -51.3  245  34 18   8.7   4.8 | -45.7 -50.3  235  36 19   8.8   4.8
 30000 -40.4 -40.7  240  30 15   8.6   4.7 | -40.1 -40.2  235  35 18   7.7   4.2
 29000 -37.9 -36.2  245  29 15   8.6   4.7 | -37.8 -36.0  235  36 19   7.7   4.2
 28000 -35.3 -31.5  245  28 15   8.6   4.7 | -35.5 -31.9  235  38 20   7.7   4.2
 27000 -32.7 -26.9  245  27 14   8.5   4.6 | -33.1 -27.6  235  39 20   8.5   4.7
 26000 -30.2 -22.4  240  24 12   8.5   4.6 | -30.5 -22.9  230  39 20   8.5   4.7
 25000 -27.6 -17.7  230  22 11   8.5   4.6 | -28.0 -18.4  225  39 20   8.5   4.7
 24000 -25.2 -13.4  225  20 10   7.7   4.2 | -25.5 -13.9  225  39 20   7.7   4.2
 23000 -22.8  -9.0  215  20 10   7.8   4.3 | -23.2  -9.8  220  38 19   7.8   4.3
 22000 -20.5  -4.9  205  21 11   7.8   4.3 | -20.8  -5.4  220  36 19   7.8   4.3
 21000 -18.3  -0.9  200  22 11   6.6   3.6 | -18.5  -1.3  215  35 18   7.4   4.1
 20000 -16.4   2.5  205  23 12   6.7   3.7 | -16.3   2.7  210  34 18   7.4   4.1
 19500 -15.4   4.3  205  24 12   6.7   3.7 | -15.2   4.6  210  33 17   7.4   4.1
 19000 -14.4   6.1  205  24 12   6.6   3.6 | -14.1   6.6  205  33 17   7.3   4.0
 18500 -13.3   8.1  205  25 13   8.3   4.6 | -12.9   8.8  205  32 17   8.4   4.6
 18000 -12.1  10.2  205  25 13   8.2   4.5 | -11.7  10.9  205  32 16   8.4   4.6
 17500 -10.9  12.4  205  25 13   8.5   4.6 | -10.4  13.3  205  31 16   8.5   4.7
 17000  -9.7  14.5  200  25 13   8.6   4.7 |  -9.1  15.6  205  29 15   8.7   4.8
 16500  -8.4  16.9  200  24 13   8.7   4.8 |  -7.8  18.0  200  27 14   8.7   4.8
 16000  -7.0  19.4  200  24 12   9.0   5.0 |  -6.5  20.3  200  26 13   8.9   4.9
 15500  -5.7  21.7  200  23 12   9.0   5.0 |  -5.1  22.8  205  24 12   8.9   4.9
 15000  -4.4  24.1  200  22 11   8.9   4.9 |  -3.1  26.4  210  23 12   9.0   5.0
 14500  -2.4  27.7  200  21 11   8.9   4.9 |  -1.8  28.8  215  23 12   9.2   5.1
 14000  -1.0  30.2  200  20 10   9.0   5.0 |  -0.6  30.9  225  25 13   7.1   3.9
 13500   0.3  32.5  205  19 10   9.0   4.9 |   0.5  32.9  230  30 15   7.4   4.0
 13000   1.7  35.1  205  19 10   9.5   5.2 |   1.5  34.7  240  34 18   6.2   3.4
 12500   3.1  37.6  215  19 10   8.9   4.9 |   2.4  36.3  240  38 20   6.2   3.4
 12000   4.3  39.7  220  21 11   8.1   4.5 |   3.3  37.9  240  42 21   7.0   3.8
 11750   4.9  40.8  225  22 11   8.3   4.5 |   3.8  38.8  240  40 20   7.3   4.0
 11500   5.5  41.9  230  23 12   8.1   4.5 |   4.3  39.7  240  38 20   7.0   3.8
 11250   6.1  43.0  230  24 12   8.6   4.7 |   4.8  40.6  240  36 19   8.5   4.7
 11000   6.7  44.1  235  26 13   8.4   4.6 |   5.5  41.9  240  34 17   9.8   5.4
 10750   7.3  45.1  235  27 14   7.6   4.2 |   6.2  43.2  240  32 17   9.2   5.1
 10500   7.9  46.2  240  28 15   8.0   4.4 |   6.9  44.4  240  31 16   9.8   5.4
 10250   8.4  47.1  240  30 15   7.3   4.0 |   7.6  45.7  240  29 15   8.2   4.5
 10000   8.9  48.0  240  32 16   6.7   3.7 |   8.1  46.6  235  28 14   8.8   4.8
  9750   9.5  49.1  245  34 17   7.0   3.9 |   8.9  48.0  235  27 14  10.7   5.9
  9500  10.0  50.0  245  36 18   7.0   3.9 |   9.6  49.3  235  26 14  10.3   5.6
  9250  10.5  50.9  250  37 19   6.8   3.8 |  10.4  50.7  235  26 13  10.1   5.6
  9000  11.0  51.8  250  38 19   6.2   3.4 |  11.1  52.0  235  25 13   9.5   5.2
  8750  11.4  52.5  250  36 19   5.5   3.0 |  11.8  53.2  230  25 13  10.1   5.5
  8500  11.8  53.2  250  34 18   5.2   2.8 |  12.6  54.7  230  24 12  10.6   5.8
  8250  12.1  53.8  250  32 16   5.5   3.0 |  13.4  56.1  230  24 12  10.5   5.7
  8000  12.5  54.5  250  28 15   5.6   3.1 |  14.2  57.6  230  23 12  10.8   5.9
  7750  12.9  55.2  250  24 12   6.3   3.5 |  14.9  58.8  230  22 11   9.9   5.4
  7500  13.4  56.1  250  20 10   7.4   4.1 |  15.6  60.1  225  21 11   8.1   4.4
  7250  13.8  56.8  250  16  8   5.6   3.1 |  16.2  61.2  225  19 10  10.6   5.8
  7000  14.1  57.4  245  14  7   2.5   1.4 |  17.2  63.0  225  18  9  16.1   8.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/23/2016 at 1500 MDT          |       04/23/2016 at 1800 MDT
                                           |
K index... +11.4  LI... +272.5             | K index... +24.4  LI... +271.3
CAPE... +141.3  CIN... -25.8               | CAPE... +242.6  CIN... -2.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.7 -75.5  305  23 12   2.9   1.6 | -59.6 -75.3  305  24 13   3.0   1.7
 45000 -55.8 -68.4  305  20 10  -5.7  -3.1 | -55.6 -68.1  295  19 10  -4.1  -2.3
 40000 -63.2 -81.8  235  51 26  -5.0  -2.7 | -60.6 -77.1  230  31 16  -3.4  -1.9
 38000 -60.9 -77.6  235  54 28   8.8   4.8 | -58.7 -73.7  230  40 21   7.5   4.1
 36000 -55.6 -68.1  230  49 25   8.8   4.8 | -53.6 -64.5  235  51 26   7.5   4.1
 34000 -50.5 -58.9  230  48 24   8.0   4.4 | -49.2 -56.6  235  58 30   7.2   3.9
 32000 -45.0 -49.0  230  53 27   8.0   4.4 | -44.9 -48.8  230  61 31   7.2   3.9
 30000 -40.3 -40.5  230  53 27   7.8   4.3 | -40.4 -40.7  230  62 32   7.8   4.3
 29000 -38.0 -36.4  230  51 26   7.8   4.3 | -38.1 -36.6  225  62 32   7.8   4.3
 28000 -35.6 -32.1  225  48 25   7.8   4.3 | -35.8 -32.4  225  62 32   7.8   4.3
 27000 -33.3 -27.9  225  47 24   7.9   4.3 | -33.5 -28.3  225  62 32   7.6   4.2
 26000 -30.9 -23.6  220  46 24   7.9   4.3 | -31.2 -24.2  220  63 32   7.6   4.2
 25000 -28.6 -19.5  220  45 23   7.9   4.3 | -29.0 -20.2  220  63 32   7.6   4.2
 24000 -26.2 -15.2  220  45 23   8.2   4.5 | -26.7 -16.1  220  64 33   7.6   4.2
 23000 -23.7 -10.7  215  43 22   8.2   4.5 | -23.9 -11.0  220  60 31   7.6   4.2
 22000 -21.3  -6.3  215  42 21   8.2   4.5 | -21.6  -6.9  220  58 30   7.7   4.2
 21000 -18.9  -2.0  215  40 21   7.7   4.2 | -19.4  -2.9  220  55 28   7.8   4.3
 20000 -16.5   2.3  220  38 20   7.8   4.3 | -17.1   1.2  220  52 27   7.8   4.3
 19500 -15.4   4.3  220  37 19   7.8   4.3 | -15.9   3.4  220  50 26   7.8   4.3
 19000 -14.2   6.4  220  36 19   7.8   4.3 | -14.7   5.5  225  48 25   7.9   4.3
 18500 -13.1   8.4  225  37 19   7.7   4.2 | -13.6   7.5  225  47 24   7.7   4.2
 18000 -11.9  10.6  225  41 21   7.7   4.2 | -12.5   9.5  225  45 23   7.7   4.2
 17500 -10.8  12.6  230  45 23   7.8   4.3 | -11.4  11.5  225  44 23   7.6   4.2
 17000  -9.6  14.7  230  47 24   8.0   4.4 | -10.3  13.5  225  42 22   7.5   4.1
 16500  -8.4  16.9  230  49 25   8.0   4.4 |  -9.2  15.4  225  41 21   7.5   4.1
 16000  -7.2  19.0  230  50 26   8.4   4.6 |  -8.1  17.4  225  39 20   7.6   4.2
 15500  -5.3  22.5  235  51 26   8.3   4.6 |  -7.0  19.4  220  36 19   7.6   4.2
 15000  -4.1  24.6  235  51 26   8.4   4.6 |  -5.8  21.6  220  34 18   8.5   4.7
 14500  -2.8  27.0  235  50 26   8.5   4.7 |  -4.5  23.9  220  32 17   8.8   4.9
 14000  -1.6  29.1  235  48 25   7.9   4.3 |  -3.3  26.1  215  30 16   9.1   5.0
 13500  -0.5  31.1  230  45 23   7.9   4.4 |  -1.9  28.6  215  29 15   9.5   5.2
 13000   0.6  33.1  230  42 21   8.7   4.8 |  -0.5  31.1  215  29 15   9.8   5.4
 12500   1.9  35.4  230  39 20   8.8   4.8 |   1.1  34.0  210  28 15  11.4   6.3
 12000   3.2  37.8  225  35 18   8.8   4.8 |   2.6  36.7  210  28 14   8.5   4.7
 11750   3.8  38.8  225  34 17   9.0   4.9 |   3.3  37.9  210  28 14   9.6   5.3
 11500   4.5  40.1  220  32 17   8.8   4.8 |   4.0  39.2  210  28 14  10.0   5.5
 11250   5.1  41.2  220  31 16   9.5   5.2 |   4.7  40.5  210  28 14   9.9   5.4
 11000   5.8  42.4  220  31 16  10.0   5.5 |   5.5  41.9  210  28 14   9.3   5.1
 10750   6.6  43.9  220  30 15   9.5   5.2 |   6.1  43.0  210  27 14   9.3   5.1
 10500   7.3  45.1  215  29 15   9.8   5.4 |   6.8  44.2  210  27 14   9.8   5.4
 10250   8.0  46.4  215  29 15   9.0   4.9 |   7.6  45.7  205  27 14   9.6   5.3
 10000   8.6  47.5  215  28 14   9.4   5.2 |   8.3  46.9  205  27 14   9.9   5.4
  9750   9.4  48.9  215  28 14  10.5   5.8 |   9.0  48.2  205  27 14   9.9   5.4
  9500  10.2  50.4  210  27 14  10.3   5.6 |  10.5  50.9  205  26 14   9.7   5.3
  9250  10.9  51.6  210  27 14  10.3   5.6 |  11.2  52.2  205  26 13   9.9   5.4
  9000  11.7  53.1  210  27 14   9.8   5.4 |  11.9  53.4  200  26 13  10.2   5.6
  8750  12.4  54.3  210  26 14   9.9   5.4 |  12.7  54.9  200  26 13  10.0   5.5
  8500  13.2  55.8  210  26 13  10.2   5.6 |  13.4  56.1  200  25 13   9.9   5.4
  8250  13.9  57.0  210  26 13  10.1   5.5 |  14.1  57.4  200  25 13   9.9   5.4
  8000  14.7  58.5  210  25 13  10.5   5.8 |  14.9  58.8  200  24 12   9.8   5.4
  7750  15.5  59.9  205  25 13   9.9   5.4 |  15.6  60.1  200  23 12  10.3   5.6
  7500  16.1  61.0  205  23 12   8.4   4.6 |  16.3  61.3  195  20 10  11.2   6.1
  7250  16.8  62.2  205  22 11  10.3   5.7 |  17.1  62.8  195  17  9   9.7   5.3
  7000  17.7  63.9  205  20 10  14.7   8.1 |     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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