Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 121104
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0404 MST Friday, February 12, 2016

This forecast is for Friday, February 12, 2016:

If the trigger temperature of 55.0 F/12.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 485 ft/min (2.5 m/s)
   Maximum height of thermals.................. 12256 ft MSL (5498 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8125 ft MSL (1367 ft AGL)
Thermal soaring outlook for Saturday 02/13..... Good

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

Remarks...

Sunrise/Sunset.................... 06:54:12 / 17:31:21 MST
Total possible sunshine........... 10 hr 37 min 10 sec (637 min 10 sec)
Altitude of sun at 12:13:05 MST... 37.40 degrees

Upper air data from numerical model forecast valid on 02/12/2016 at 0500 MST

Freezing level.................. 7020 ft MSL (262 ft AGL)
Additional freezing level....... 11528 ft MSL (4770 ft AGL)
Convective condensation level... 17337 ft MSL (10579 ft AGL)
Lifted condensation level....... 15157 ft MSL (8400 ft AGL)
Lifted index.................... +3.0
K index......................... +16.0

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   305   53   27   2.4   1.3      M     M       M      M    M
 45000  -58.7 -73.7   310   67   34  -2.9  -1.6      M     M       M      M    M
 40000  -63.9 -83.0   305   59   30  -3.6  -1.9      M     M       M      M    M
 38000  -62.1 -79.8   305   57   30   7.0   3.9      M     M       M      M    M
 36000  -57.9 -72.2   305   57   29   7.0   3.9      M     M       M      M    M
 34000  -52.8 -63.0   305   57   29   8.2   4.5      M     M       M      M    M
 32000  -47.9 -54.2   305   55   29   8.2   4.5      M     M       M      M    M
 30000  -42.9 -45.2   305   54   28   8.3   4.5   26.4  79.6    10.1      M    M
 29000  -40.5 -40.9   305   52   27   8.3   4.5   25.8  78.5     9.7      M    M
 28000  -38.0 -36.4   310   51   26   8.3   4.5   25.3  77.6     9.4      M    M
 27000  -35.6 -32.1   310   50   26   7.9   4.3   24.7  76.5     9.1      M    M
 26000  -33.2 -27.8   310   48   25   7.9   4.4   24.0  75.2     8.6      M    M
 25000  -30.8 -23.4   310   46   24   7.9   4.4   23.4  74.0     8.1      M    M
 24000  -28.4 -19.1   305   44   23   8.0   4.4   22.8  73.0     7.7      M    M
 23000  -26.1 -15.0   305   43   22   8.0   4.4   22.0  71.7     7.2      M    M
 22000  -23.7 -10.7   310   41   21   8.0   4.4   21.5  70.6     6.8      M    M
 21000  -21.3  -6.3   310   39   20   7.8   4.3   20.8  69.5     6.3      M    M
 20000  -19.0  -2.2   310   38   19   7.8   4.3   20.1  68.2     5.7      M    M
 19500  -17.8  -0.0   310   37   19   7.8   4.3   19.8  67.7     5.5      M    M
 19000  -16.7   1.9   310   36   19   7.9   4.3   19.5  67.2     5.2      M    M
 18500  -15.5   4.1   310   35   18   8.0   4.4   19.2  66.6     5.0      M    M
 18000  -14.3   6.3   315   34   18   8.1   4.4   18.9  66.1     4.7      M    M
 17500  -13.1   8.4   315   33   17   7.6   4.2   18.6  65.5     4.5      M    M
 17000  -12.0  10.4   315   32   17   7.6   4.1   18.3  64.9     4.1      M    M
 16500  -10.3  13.5   320   31   16   7.0   3.9   17.7  63.8     3.6      M    M
 16000   -9.3  15.3   320   31   16   7.1   3.9   17.2  63.0     3.2      M    M
 15500   -8.3  17.1   320   30   16   7.0   3.9   16.8  62.2     2.8      M    M
 15000   -7.2  19.0   320   29   15   7.0   3.9   16.3  61.4     2.4      M    M
 14500   -6.2  20.8   325   28   14   6.9   3.8   15.9  60.6     2.0      M    M
 14000   -5.2  22.6   325   27   14   6.6   3.6   15.4  59.7     1.5      M    M
 13500   -4.3  24.3   325   25   13   6.7   3.7   14.9  58.8     1.0      M    M
 13000   -3.3  26.1   325   24   12   6.9   3.8   14.4  57.9     0.6      M    M
 12500   -2.2  28.0   320   22   11   7.2   4.0   14.0  57.1     0.1      M    M
 12000   -1.0  30.2   320   21   11   8.4   4.6   13.7  56.6    -0.2    452  2.3
 11750   -0.4  31.3   325   20   11   8.3   4.5   13.6  56.4    -0.3    426  2.2
 11500    0.2  32.4   325   20   10   8.6   4.7   13.5  56.2    -0.4    399  2.0
 11250    0.9  33.6   325   20   10   9.6   5.3   13.4  56.2    -0.4    372  1.9
 11000    1.6  34.9   325   20   10   8.9   4.9   13.4  56.1    -0.4    343  1.7
 10750    2.2  36.0   325   21   11   7.8   4.3   13.3  55.9    -0.6    317  1.6
 10500    2.8  37.0   325   21   11   8.2   4.5   13.1  55.7    -0.7    291  1.5
 10250    3.5  38.3   325   21   11   8.6   4.7   13.0  55.5    -0.8    265  1.3
 10000    4.1  39.4   330   20   10   8.4   4.6   13.0  55.3    -0.9    238  1.2
  9750    4.7  40.5   330   19   10   7.8   4.3   12.8  55.1    -1.0    212  1.1
  9500    5.3  41.5   330   18    9   7.3   4.0   12.7  54.8    -1.1    188  1.0
  9250    5.8  42.4   330   17    9   7.0   3.8   12.4  54.4    -1.3    164  0.8
  9000    6.4  43.5   325   16    8   6.2   3.4   12.2  54.0    -1.6    141  0.7
  8750    6.9  44.4   325   15    8  10.0   5.5   12.0  53.6    -1.7    118  0.6
  8500    7.7  45.9   325   15    8   4.9   2.7   12.0  53.7    -1.7     88  0.4
  8250    7.5  45.5   325   14    7  -5.2  -2.9   11.2  52.1    -2.6     84  0.4
  8000    7.4  45.3   320   13    7   5.5   3.0   10.3  50.5    -3.5     80  0.4
  7750    7.3  45.1   315   13    6 -27.2 -14.9    9.4  49.0    -4.3     77  0.4
  7500    3.6  38.5   305   12    6 -42.9 -23.5    5.3  41.5    -8.6    178  0.9
  7250    1.8  35.2   305   10    5 -16.8  -9.2    3.0  37.5   -10.8    227  1.2
  7000   -0.1  31.8   295    9    5 -39.2 -21.5    0.8  33.4   -13.1    276  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           02/12/2016 at 0800 MST          |       02/12/2016 at 1100 MST
                                           |
K index... +16.8  LI... +274.7             | K index... +16.8  LI... +274.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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 -61.6 -78.9  300  54 28   2.2   1.2 | -62.2 -80.0  295  54 28   2.7   1.5
 45000 -58.4 -73.1  300  70 36  -1.9  -1.0 | -58.4 -73.1  295  73 38  -2.2  -1.2
 40000 -63.2 -81.8  310  61 31  -2.9  -1.6 | -63.1 -81.6  305  63 33  -2.7  -1.5
 38000 -61.1 -78.0  310  61 32   6.3   3.5 | -60.8 -77.4  310  62 32   6.4   3.5
 36000 -57.3 -71.1  310  63 32   6.3   3.5 | -57.0 -70.6  315  63 32   6.4   3.5
 34000 -53.0 -63.4  310  63 33   8.5   4.7 | -52.6 -62.7  315  62 32   8.7   4.8
 32000 -47.9 -54.2  310  61 32   8.5   4.7 | -47.4 -53.3  315  59 30   8.6   4.7
 30000 -42.9 -45.2  310  59 30   8.2   4.5 | -42.2 -44.0  315  56 29   8.4   4.6
 29000 -40.5 -40.9  310  57 29   8.2   4.5 | -39.7 -39.5  315  55 28   8.4   4.6
 28000 -38.0 -36.4  310  55 28   8.2   4.5 | -37.2 -35.0  315  53 27   8.4   4.6
 27000 -35.0 -31.0  310  53 27   8.1   4.4 | -34.7 -30.5  315  52 27   8.2   4.5
 26000 -32.6 -26.7  310  51 26   8.1   4.4 | -31.6 -24.9  315  50 26   8.2   4.5
 25000 -30.2 -22.4  310  50 26   8.1   4.4 | -29.2 -20.6  315  49 25   8.2   4.5
 24000 -27.8 -18.0  310  48 25   7.6   4.1 | -26.9 -16.4  315  47 24   7.1   3.9
 23000 -25.6 -14.1  310  46 23   7.6   4.2 | -24.7 -12.5  315  45 23   7.1   3.9
 22000 -23.3  -9.9  310  43 22   7.6   4.2 | -22.6  -8.7  310  42 22   7.1   3.9
 21000 -21.1  -6.0  310  40 21   7.2   3.9 | -20.7  -5.3  310  39 20   6.2   3.4
 20000 -19.0  -2.2  310  38 19   7.2   3.9 | -18.9  -2.0  310  36 18   6.2   3.4
 19500 -17.9  -0.2  310  37 19   7.2   3.9 | -18.0  -0.4  310  34 18   6.2   3.4
 19000 -16.9   1.6  310  35 18   7.2   4.0 | -17.1   1.2  310  33 17   6.4   3.5
 18500 -15.8   3.6  315  34 18   7.4   4.0 | -16.1   3.0  310  32 16   6.6   3.6
 18000 -14.7   5.5  315  33 17   7.4   4.0 | -15.1   4.8  310  31 16   6.6   3.6
 17500 -13.6   7.5  315  32 17   7.1   3.9 | -14.1   6.6  310  30 15   7.3   4.0
 17000 -12.6   9.3  315  31 16   7.1   3.9 | -13.1   8.4  315  29 15   7.2   4.0
 16500 -11.6  11.1  320  31 16   7.1   3.9 | -12.0  10.4  315  28 15   7.5   4.1
 16000 -10.5  13.1  320  30 15   7.0   3.8 | -10.9  12.4  315  28 14   7.7   4.2
 15500  -9.5  14.9  320  29 15   7.1   3.9 |  -9.8  14.4  315  27 14   7.9   4.3
 15000  -8.5  16.7  320  28 14   7.4   4.1 |  -8.6  16.5  315  26 13   8.3   4.6
 14500  -7.4  18.7  320  27 14   7.4   4.1 |  -7.3  18.9  315  25 13   8.3   4.5
 14000  -6.3  20.7  320  25 13   7.5   4.1 |  -6.1  21.0  315  24 13   8.2   4.5
 13500  -4.6  23.7  320  23 12   7.6   4.1 |  -4.9  23.2  315  23 12   8.2   4.5
 13000  -3.5  25.7  320  22 11   7.7   4.2 |  -3.7  25.3  315  22 11   8.3   4.5
 12500  -2.3  27.9  320  21 11   7.1   3.9 |  -2.4  27.7  315  21 11   8.5   4.7
 12000  -1.1  30.0  325  21 11   9.5   5.2 |  -1.3  29.7  315  19 10   7.5   4.1
 11750  -0.4  31.3  325  21 11   9.1   5.0 |  -0.6  30.9  315  18  9   9.1   5.0
 11500   0.2  32.4  325  21 11   9.1   5.0 |   0.0  32.0  315  17  9   8.9   4.9
 11250   0.9  33.6  330  21 11   8.8   4.9 |   0.7  33.3  310  16  8   8.3   4.6
 11000   1.6  34.9  330  21 11   8.2   4.5 |   1.3  34.3  310  15  8   7.6   4.2
 10750   2.2  36.0  330  20 11   7.9   4.3 |   1.9  35.4  310  14  7   7.8   4.3
 10500   2.8  37.0  330  20 10   7.9   4.3 |   2.5  36.5  305  13  7   7.9   4.3
 10250   3.3  37.9  330  19 10   7.8   4.3 |   3.1  37.6  305  12  6   7.5   4.1
 10000   3.9  39.0  330  17  9   7.6   4.2 |   4.2  39.6  300  10  5   6.9   3.8
  9750   4.5  40.1  330  16  8   7.3   4.0 |   4.7  40.5  295   9  4   6.3   3.4
  9500   5.0  41.0  330  15  7   7.1   3.9 |   5.1  41.2  295   8  4   6.2   3.4
  9250   5.6  42.1  330  13  7   7.1   3.9 |   5.6  42.1  290   7  4   5.9   3.2
  9000   6.1  43.0  330  12  6   6.8   3.8 |   6.1  43.0  290   6  3   6.3   3.5
  8750   6.6  43.9  335  11  6   8.5   4.7 |   6.5  43.7  285   5  3   5.8   3.2
  8500   7.3  45.1  335  10  5   4.8   2.7 |   6.9  44.4  285   4  2   3.6   2.0
  8250   7.3  45.1  330  10  5  -1.7  -1.0 |   7.1  44.8  280   4  2   2.3   1.3
  8000   7.4  45.3  330  10  5   6.6   3.6 |   7.2  45.0  280   3  2   3.6   2.0
  7750   7.4  45.3  325   9  5 -20.1 -11.0 |   7.1  44.8  275   3  1  -7.9  -4.3
  7500   4.5  40.1  320   9  5 -36.5 -20.0 |   5.4  41.7  280   3  2 -28.9 -15.9
  7250   2.7  36.9  310   8  4 -18.1  -9.9 |   3.8  38.8  280   4  2  10.9   6.0
  7000   0.9  33.6  305   8  4 -34.2 -18.8 |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/12/2016 at 1400 MST          |       02/12/2016 at 1700 MST
                                           |
K index... +16.4  LI... +274.1             | K index... +11.1  LI... +273.7
CAPE... 0.0  CIN... -0.3                   | CAPE... +7.3  CIN... -18.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.4 -80.3  290  51 26   2.5   1.3 | -62.0 -79.6  290  52 27   1.8   1.0
 45000 -58.9 -74.0  285  77 40  -1.6  -0.9 | -59.5 -75.1  290  77 40  -1.7  -0.9
 40000 -62.8 -81.0  305  67 35  -2.3  -1.3 | -63.6 -82.5  300  63 32  -2.4  -1.3
 38000 -60.5 -76.9  305  65 33   6.3   3.5 | -61.1 -78.0  305  60 31   6.9   3.8
 36000 -56.8 -70.2  310  62 32   6.3   3.5 | -57.0 -70.6  305  58 30   6.9   3.8
 34000 -52.5 -62.5  310  60 31   8.5   4.6 | -52.5 -62.5  305  55 28   8.4   4.6
 32000 -47.4 -53.3  310  57 29   8.4   4.6 | -47.4 -53.3  310  53 27   8.4   4.6
 30000 -42.4 -44.3  310  54 28   8.0   4.4 | -42.5 -44.5  310  50 26   8.0   4.4
 29000 -39.4 -38.9  310  51 26   8.0   4.4 | -39.5 -39.1  305  49 25   8.0   4.4
 28000 -37.0 -34.6  305  49 25   8.1   4.4 | -37.1 -34.8  305  48 25   8.0   4.4
 27000 -34.5 -30.1  310  47 24   8.5   4.7 | -34.7 -30.5  305  46 24   8.1   4.4
 26000 -32.0 -25.6  310  45 23   8.5   4.7 | -32.3 -26.1  305  44 23   8.1   4.4
 25000 -29.5 -21.1  315  44 22   8.5   4.7 | -29.9 -21.8  310  41 21   8.1   4.4
 24000 -27.0 -16.6  315  42 22   7.8   4.3 | -27.5 -17.5  310  40 21   8.0   4.4
 23000 -24.7 -12.5  315  41 21   7.8   4.3 | -25.1 -13.2  310  39 20   8.0   4.4
 22000 -22.3  -8.1  315  40 21   7.8   4.3 | -22.7  -8.9  315  39 20   8.0   4.4
 21000 -20.2  -4.4  315  39 20   6.5   3.5 | -20.4  -4.7  315  38 20   7.6   4.2
 20000 -18.3  -0.9  315  37 19   6.4   3.5 | -18.1  -0.6  320  37 19   7.6   4.2
 19500 -17.4   0.7  315  36 19   6.4   3.5 | -16.9   1.6  320  36 18   7.6   4.2
 19000 -16.4   2.5  315  35 18   6.4   3.5 | -15.8   3.6  325  35 18   7.4   4.0
 18500 -15.5   4.1  315  34 18   6.1   3.4 | -14.8   5.4  325  34 18   6.7   3.7
 18000 -14.6   5.7  315  33 17   6.1   3.3 | -13.8   7.2  325  33 17   6.7   3.7
 17500 -13.7   7.3  315  32 17   7.2   4.0 | -12.8   9.0  325  32 16   7.2   4.0
 17000 -12.6   9.3  315  31 16   7.3   4.0 | -11.7  10.9  325  31 16   7.3   4.0
 16500 -11.5  11.3  310  31 16   7.2   4.0 | -10.6  12.9  320  30 15   7.4   4.1
 16000 -10.5  13.1  310  30 15   7.1   3.9 |  -9.5  14.9  320  29 15   7.6   4.2
 15500  -9.4  15.1  310  29 15   7.3   4.0 |  -8.4  16.9  320  28 15   7.7   4.2
 15000  -8.3  17.1  310  28 14   8.3   4.5 |  -7.2  19.0  320  27 14   8.0   4.4
 14500  -6.5  20.3  305  26 13   8.6   4.7 |  -5.5  22.1  315  26 13   7.9   4.3
 14000  -5.2  22.6  305  24 12   8.8   4.9 |  -4.3  24.3  315  25 13   7.9   4.3
 13500  -3.9  25.0  305  22 12   8.9   4.9 |  -3.2  26.2  310  24 12   8.0   4.4
 13000  -2.6  27.3  300  21 11   9.1   5.0 |  -2.0  28.4  310  23 12   8.4   4.6
 12500  -1.2  29.8  300  19 10   8.5   4.7 |  -0.8  30.6  310  22 11   8.6   4.7
 12000   0.1  32.2  300  18  9   9.4   5.1 |   0.5  32.9  315  21 11   8.7   4.8
 11750   0.8  33.4  300  18  9   9.2   5.0 |   1.2  34.2  315  21 11   8.7   4.8
 11500   1.5  34.7  300  18  9   9.2   5.0 |   1.8  35.2  315  20 11   9.0   4.9
 11250   2.2  36.0  300  17  9   9.1   4.9 |   2.5  36.5  310  20 10   9.6   5.2
 11000   2.9  37.2  295  16  8   8.5   4.7 |   3.2  37.8  310  19 10   9.1   5.0
 10750   3.5  38.3  295  16  8   8.4   4.6 |   3.9  39.0  310  19 10   8.7   4.8
 10500   4.1  39.4  290  15  8   8.1   4.5 |   4.6  40.3  305  18  9   8.8   4.9
 10250   4.7  40.5  285  14  7   7.5   4.1 |   5.2  41.4  305  17  9   9.1   5.0
 10000   5.3  41.5  280  13  7   7.3   4.0 |   5.9  42.6  300  17  9   8.8   4.8
  9750   5.9  42.6  280  12  6   7.8   4.3 |   6.5  43.7  300  16  8   8.5   4.7
  9500   6.4  43.5  275  11  6   6.8   3.7 |   7.2  45.0  295  16  8   7.5   4.1
  9250   6.9  44.4  270  11  5   5.4   3.0 |   7.6  45.7  295  16  8   6.1   3.4
  9000   7.3  45.1  270  10  5   5.2   2.8 |   8.0  46.4  290  15  8   5.5   3.0
  8750   7.7  45.9  265  10  5   6.2   3.4 |   8.5  47.3  290  15  8   8.9   4.9
  8500   8.1  46.6  260  10  5   2.4   1.3 |   9.1  48.4  285  14  7   4.6   2.5
  8250   8.0  46.4  255   9  5  -1.2  -0.7 |   9.0  48.2  280  13  7  -2.0  -1.1
  8000   7.9  46.2  250   9  4   0.1   0.1 |   8.8  47.8  275  11  6   0.7   0.4
  7750   7.8  46.0  245   8  4  -0.8  -0.4 |   8.7  47.7  265  10  5  -3.3  -1.8
  7500   7.4  45.3  230   7  4  -3.9  -2.1 |   8.0  46.4  260   8  4 -11.7  -6.4
  7250   6.9  44.4  230   6  3  -5.8  -3.2 |   7.0  44.6  255   7  4 -14.6  -8.0
  7000   6.4  43.5  225   5  3  -4.2  -2.3 |   5.9  42.6  255   6  3 -12.7  -7.0
  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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