Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 231239
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Soaring Forecast
National Weather Service Pueblo, Colorado
0639 MDT Monday, October 23, 2017

This forecast is for Monday, October 23, 2017:

If the trigger temperature of 56.2 F/13.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 335 ft/min (1.7 m/s)
   Maximum height of thermals.................. 13954 ft MSL (6334 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11716 ft MSL (4096 ft AGL)
Thermal soaring outlook for Tuesday 10/24...... Fair

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

Remarks...

Sunrise/Sunset.................... 07:17:30 / 18:09:31 MDT
Total possible sunshine........... 10 hr 52 min 1 sec (652 min 1 sec)
Altitude of sun at 12:43:31 MDT... 39.22 degrees

Upper air data from numerical model forecast valid on 10/23/2017 at 0600 MDT

Freezing level.................. 12352 ft MSL (4732 ft AGL)
Convective condensation level... 20152 ft MSL (12532 ft AGL)
Lifted condensation level....... 16861 ft MSL (9240 ft AGL)
Lifted index.................... +5.8
K index......................... +3.2

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  -63.7 -82.7   300   25   13  -0.7  -0.4      M     M       M      M    M
 45000  -64.3 -83.7   300   41   21   1.3   0.7      M     M       M      M    M
 40000  -62.1 -79.8   320   42   22   5.2   2.9      M     M       M      M    M
 38000  -57.4 -71.3   315   42   22   7.9   4.3      M     M       M      M    M
 36000  -52.6 -62.7   310   42   21   7.9   4.3      M     M       M      M    M
 34000  -47.3 -53.1   305   40   20   9.4   5.1      M     M       M      M    M
 32000  -41.6 -42.9   300   37   19   9.4   5.2      M     M       M      M    M
 30000  -36.3 -33.3   300   37   19   8.8   4.8   32.4  90.3    12.2      M    M
 29000  -33.6 -28.5   300   38   20   8.8   4.8   32.0  89.7    12.0      M    M
 28000  -31.0 -23.8   300   39   20   8.8   4.9   31.8  89.2    12.0      M    M
 27000  -28.5 -19.3   300   38   20   8.4   4.6   31.3  88.3    11.7      M    M
 26000  -26.0 -14.8   300   37   19   8.4   4.6   30.7  87.3    11.4      M    M
 25000  -23.5 -10.3   300   36   19   8.4   4.6   30.3  86.5    11.1      M    M
 24000  -21.1  -6.0   300   35   18   7.6   4.2   29.7  85.4    10.7      M    M
 23000  -18.2  -0.8   305   33   17   7.6   4.2   28.7  83.6    10.0      M    M
 22000  -16.0   3.2   305   31   16   7.5   4.1   28.0  82.4     9.5      M    M
 21000  -13.9   7.0   305   29   15   6.6   3.6   26.9  80.4     8.7      M    M
 20000  -12.0  10.4   305   27   14   6.6   3.6   25.8  78.4     7.8      M    M
 19500  -11.0  12.2   310   26   13   6.6   3.6   25.3  77.5     7.4      M    M
 19000  -10.0  14.0   310   24   12   6.1   3.4   24.7  76.5     7.0      M    M
 18500   -9.1  15.6   310   23   12   6.1   3.3   24.1  75.4     6.4      M    M
 18000   -8.2  17.2   310   21   11   6.0   3.3   23.5  74.3     5.9      M    M
 17500   -7.4  18.7   315   21   11   5.9   3.3   22.9  73.1     5.4      M    M
 17000   -6.5  20.3   315   20   10   6.1   3.3   22.2  72.0     4.8      M    M
 16500   -5.7  21.7   315   19   10   4.7   2.6   21.5  70.7     4.2      M    M
 16000   -5.0  23.0   315   18    9   4.7   2.6   20.7  69.2     3.4      M    M
 15500   -4.3  24.3   315   17    9   4.5   2.4   19.9  67.7     2.6      M    M
 15000   -3.7  25.3   315   16    8   4.3   2.4   19.0  66.1     1.8      M    M
 14500   -3.1  26.4   315   15    8   4.4   2.4   18.1  64.5     1.0      M    M
 14000   -2.5  27.5   315   14    7   4.5   2.5   17.2  63.0     0.1      M    M
 13500   -1.8  28.8   310   12    6   4.6   2.5   16.4  61.5    -0.7    506  2.6
 13000   -1.1  30.0   310   12    6   5.6   3.1   15.7  60.2    -1.4    469  2.4
 12500   -0.3  31.5   310   11    6   5.0   2.7   15.0  58.9    -2.1    431  2.2
 12000    0.6  33.1   310   11    5   7.0   3.9   14.4  57.9    -2.7    389  2.0
 11750    1.1  34.0   310   10    5   7.5   4.1   14.2  57.5    -2.9    366  1.9
 11500    1.6  34.9   310   10    5   4.8   2.6   14.0  57.1    -3.1    343  1.7
 11250    1.9  35.4   310   10    5   4.7   2.6   13.5  56.2    -3.6    328  1.7
 11000    2.4  36.3   310   10    5   7.7   4.2   13.2  55.8    -3.9    306  1.6
 10750    2.9  37.2   310   10    5   6.3   3.4   13.0  55.4    -4.1    283  1.4
 10500    3.4  38.1   310   10    5   8.9   4.9   12.8  55.1    -4.3    260  1.3
 10250    4.1  39.4   310   10    5   8.4   4.6   12.8  55.1    -4.3    231  1.2
 10000    4.6  40.3   310    9    5   5.8   3.2   12.5  54.6    -4.6    209  1.1
  9750    5.1  41.2   315    9    5   6.2   3.4   12.3  54.1    -4.9    187  1.0
  9500    5.6  42.1   315    9    5   7.1   3.9   12.0  53.6    -5.1    166  0.8
  9250    6.2  43.2   315    9    4   8.6   4.7   11.9  53.4    -5.3    140  0.7
  9000    6.8  44.2   320    8    4   6.8   3.7   11.8  53.2    -5.4    115  0.6
  8750    7.2  45.0   320    8    4   5.8   3.2   11.5  52.6    -5.7     94  0.5
  8500    7.7  45.9   320    7    4   5.1   2.8   11.2  52.1    -6.0     73  0.4
  8250    8.0  46.4   320    8    4   3.0   1.6   10.7  51.3    -6.4     57  0.3
  8000    8.1  46.6   315    8    4  -0.8  -0.4   10.1  50.2    -7.1     46  0.2
  7750    7.6  45.7   310    8    4 -17.1  -9.4    8.8  47.9    -8.4     55  0.3
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           10/23/2017 at 0900 MDT          |       10/23/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +7.2        | CAPE...    +0.3    LI...       +7.5
CINH...     0.0    K Index...  -1.1        | CINH...     0.0    K Index...  -1.4
                                           |
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 -63.7 -82.7  305  27 14  -1.9  -1.0 | -63.5 -82.3  305  27 14  -0.5  -0.3
 45000 -65.5 -85.9  305  37 19   2.8   1.6 | -63.8 -82.8  305  36 19   1.0   0.6
 40000 -60.9 -77.6  310  42 22   6.4   3.5 | -62.3 -80.1  320  45 23   2.4   1.3
 38000 -56.2 -69.2  315  41 21   7.7   4.3 | -56.5 -69.7  310  42 21   9.1   5.0
 36000 -51.6 -60.9  315  40 21   7.8   4.3 | -51.0 -59.8  305  39 20   9.1   5.0
 34000 -46.2 -51.2  310  39 20   9.6   5.3 | -45.5 -49.9  305  40 20   9.1   5.0
 32000 -40.4 -40.7  310  39 20   9.6   5.3 | -40.0 -40.0  310  42 22   9.2   5.0
 30000 -35.0 -31.0  310  40 21   8.7   4.8 | -35.0 -31.0  315  42 22   7.9   4.3
 29000 -32.4 -26.3  310  41 21   8.7   4.8 | -32.6 -26.7  315  41 21   7.9   4.3
 28000 -29.8 -21.6  315  42 22   8.9   4.9 | -30.3 -22.5  320  41 21   7.8   4.3
 27000 -27.5 -17.5  315  41 21   7.1   3.9 | -27.8 -18.0  320  41 21   8.4   4.6
 26000 -25.4 -13.7  315  40 20   7.1   3.9 | -25.3 -13.5  325  41 21   8.4   4.6
 25000 -23.3  -9.9  315  38 20   7.1   3.9 | -22.8  -9.0  325  41 21   8.3   4.6
 24000 -21.2  -6.2  315  36 19   7.2   3.9 | -20.5  -4.9  325  40 21   6.9   3.8
 23000 -18.5  -1.3  310  34 17   7.2   3.9 | -17.9  -0.2  325  39 20   6.9   3.8
 22000 -16.3   2.7  310  32 16   7.2   3.9 | -15.9   3.4  325  38 20   6.8   3.7
 21000 -14.2   6.4  310  31 16   7.0   3.8 | -13.9   7.0  325  37 19   6.5   3.5
 20000 -12.2  10.0  310  30 16   7.0   3.8 | -12.0  10.4  320  35 18   6.5   3.6
 19500 -11.1  12.0  310  30 15   7.1   3.9 | -11.1  12.0  315  35 18   6.5   3.6
 19000 -10.1  13.8  310  29 15   6.3   3.5 | -10.1  13.8  315  34 18   6.0   3.3
 18500  -9.2  15.4  310  29 15   6.3   3.4 |  -9.2  15.4  315  34 17   6.0   3.3
 18000  -8.3  17.1  315  28 14   6.2   3.4 |  -8.4  16.9  315  33 17   5.9   3.3
 17500  -7.3  18.9  315  27 14   6.1   3.3 |  -7.5  18.5  315  33 17   5.7   3.1
 17000  -6.4  20.5  315  27 14   6.2   3.4 |  -6.6  20.1  315  32 17   5.9   3.2
 16500  -5.6  21.9  315  26 13   5.0   2.7 |  -5.9  21.4  315  32 16   4.1   2.3
 16000  -4.8  23.4  315  24 13   5.0   2.7 |  -5.3  22.5  315  30 16   4.1   2.2
 15500  -4.1  24.6  315  23 12   4.1   2.3 |  -4.6  23.7  315  29 15   3.4   1.9
 15000  -3.6  25.5  315  22 11   3.5   1.9 |  -4.2  24.4  310  27 14   2.9   1.6
 14500  -3.1  26.4  315  21 11   3.1   1.7 |  -3.8  25.2  310  26 13   2.5   1.4
 14000  -2.8  27.0  315  19 10   1.8   1.0 |  -3.5  25.7  310  24 12   1.7   1.0
 13500  -2.6  27.3  315  18  9   2.0   1.1 |  -3.3  26.1  305  22 11   1.5   0.8
 13000  -2.3  27.9  315  16  8   3.2   1.8 |  -3.3  26.1  300  19 10  -0.5  -0.3
 12500  -1.9  28.6  320  15  7   2.2   1.2 |  -3.6  25.5  295  17  9  -0.7  -0.4
 12000  -1.4  29.5  320  15  8   4.8   2.6 |  -3.2  26.2  295  16  8   6.4   3.5
 11750  -1.1  30.0  320  15  8   5.1   2.8 |  -2.8  27.0  290  15  8   5.5   3.0
 11500  -0.8  30.6  320  15  8   3.0   1.6 |  -2.4  27.7  290  14  7   6.1   3.3
 11250  -0.7  30.7  315  15  8   3.0   1.6 |  -1.9  28.6  285  13  7   7.4   4.1
 11000  -0.3  31.5  320  14  7   5.6   3.1 |  -1.3  29.7  285  12  6   8.2   4.5
 10750   0.1  32.2  320  13  7   4.0   2.2 |  -0.7  30.7  290  11  5   7.7   4.2
 10500   0.4  32.7  320  12  6   8.0   4.4 |  -0.2  31.6  290   9  5   8.8   4.9
 10250   1.2  34.2  320  12  6   9.7   5.3 |   0.5  32.9  290   8  4   9.3   5.1
 10000   1.8  35.2  325  11  6   7.2   3.9 |   1.2  34.2  295   7  4   8.6   4.7
  9750   2.4  36.3  325  10  5   7.7   4.2 |   1.8  35.2  300   6  3   8.5   4.7
  9500   2.9  37.2  325  10  5   8.2   4.5 |   2.5  36.5  310   5  3   9.5   5.2
  9250   3.6  38.5  330   9  5   9.1   5.0 |   3.3  37.9  320   5  2  10.7   5.9
  9000   4.3  39.7  335   9  5   8.3   4.5 |   4.0  39.2  325   4  2   9.8   5.4
  8750   4.9  40.8  340   9  5   7.8   4.3 |   4.7  40.5  330   4  2   9.0   4.9
  8500   5.5  41.9  340   9  5   7.6   4.2 |   5.4  41.7  340   4  2  10.3   5.6
  8250   6.0  42.8  345   9  5   7.3   4.0 |   6.3  43.3  340   4  2  12.0   6.6
  8000   6.6  43.9  350   9  5   6.6   3.6 |   7.1  44.8  345   4  2   9.5   5.2
  7750   7.1  44.8  350   9  5   7.2   3.9 |   7.9  46.2  345   4  2  13.7   7.5
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/23/2017 at 1500 MDT          |       10/23/2017 at 1800 MDT
                                           |
CAPE...    +0.1    LI...       +4.7        | CAPE...     0.0    LI...       +6.3
CINH...    -0.2    K Index...  +6.8        | CINH...     0.0    K Index...  +0.6
                                           |
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 -64.0 -83.2  315  27 14   0.0   0.0 | -64.4 -83.9  320  28 14   0.1   0.1
 45000 -63.6 -82.5  320  39 20   1.2   0.7 | -63.8 -82.8  325  39 20   1.9   1.0
 40000 -61.8 -79.2  315  49 25   2.8   1.5 | -61.0 -77.8  315  49 25   3.1   1.7
 38000 -55.7 -68.3  315  46 24   9.5   5.2 | -55.1 -67.2  310  47 24   9.1   5.0
 36000 -50.0 -58.0  310  43 22   9.4   5.2 | -49.7 -57.5  310  45 23   9.1   5.0
 34000 -44.8 -48.6  315  43 22   8.4   4.6 | -45.0 -49.0  315  44 23   7.1   3.9
 32000 -39.8 -39.6  315  43 22   8.4   4.6 | -40.8 -41.4  325  45 23   7.1   3.9
 30000 -35.2 -31.4  320  42 22   7.3   4.0 | -36.4 -33.5  325  43 22   7.6   4.2
 29000 -33.0 -27.4  320  42 21   7.3   4.0 | -34.1 -29.4  325  42 22   7.6   4.2
 28000 -30.8 -23.4  320  41 21   7.3   4.0 | -31.8 -25.2  325  41 21   7.5   4.1
 27000 -28.5 -19.3  320  40 21   7.7   4.2 | -29.4 -20.9  325  40 20   8.2   4.5
 26000 -26.2 -15.2  325  39 20   7.7   4.2 | -26.9 -16.4  330  39 20   8.2   4.5
 25000 -23.9 -11.0  325  38 20   7.7   4.2 | -24.5 -12.1  330  38 19   8.3   4.5
 24000 -21.6  -6.9  325  38 19   7.8   4.3 | -21.9  -7.4  330  37 19   8.7   4.8
 23000 -19.3  -2.7  325  38 19   7.8   4.3 | -19.3  -2.7  335  37 19   8.7   4.8
 22000 -16.3   2.7  330  38 19   7.7   4.2 | -16.0   3.2  335  37 19   8.5   4.7
 21000 -14.7   5.5  325  37 19   5.2   2.8 | -14.3   6.3  335  36 19   5.4   2.9
 20000 -13.1   8.4  325  36 18   5.2   2.9 | -12.7   9.1  330  36 18   5.4   3.0
 19500 -12.3   9.9  325  35 18   5.2   2.9 | -11.9  10.6  330  35 18   5.5   3.0
 19000 -11.6  11.1  320  34 18   5.5   3.0 | -11.2  11.8  330  35 18   3.8   2.1
 18500 -10.8  12.6  320  34 18   5.6   3.1 | -10.6  12.9  325  33 17   3.7   2.0
 18000  -9.9  14.2  320  34 17   5.7   3.1 | -10.1  13.8  325  32 17   3.7   2.0
 17500  -9.1  15.6  320  33 17   5.9   3.2 |  -9.6  14.7  325  31 16   3.7   2.0
 17000  -8.2  17.2  320  32 17   6.1   3.3 |  -9.0  15.8  325  30 15   3.6   2.0
 16500  -7.5  18.5  320  31 16   3.4   1.9 |  -8.4  16.9  325  28 15   4.4   2.4
 16000  -7.0  19.4  315  30 15   3.4   1.9 |  -7.8  18.0  325  27 14   4.4   2.4
 15500  -6.5  20.3  315  28 14   2.9   1.6 |  -7.1  19.2  320  25 13   4.4   2.4
 15000  -6.1  21.0  310  25 13   2.7   1.5 |  -6.5  20.3  320  23 12   4.4   2.4
 14500  -5.8  21.6  300  23 12   4.0   2.2 |  -5.9  21.4  315  21 11   4.9   2.7
 14000  -4.9  23.2  290  21 11   6.9   3.8 |  -5.1  22.8  310  19 10   5.7   3.1
 13500  -4.0  24.8  280  19 10   7.0   3.8 |  -4.3  24.3  305  18  9   6.3   3.5
 13000  -3.0  26.6  275  17  9   6.5   3.6 |  -3.2  26.2  300  17  9   8.3   4.6
 12500  -1.9  28.6  270  16  8   9.3   5.1 |  -1.8  28.8  290  16  8  10.8   5.9
 12000  -1.0  30.2  265  14  7   4.2   2.3 |  -0.7  30.7  290  15  8   5.8   3.2
 11750  -0.7  30.7  265  13  6   4.1   2.3 |  -0.3  31.5  290  14  7   5.6   3.0
 11500  -0.4  31.3  260  11  6   6.4   3.5 |   0.2  32.4  290  14  7   8.7   4.8
 11250   0.2  32.4  260  11  5   6.6   3.6 |   0.9  33.6  290  13  7   6.1   3.4
 11000   0.5  32.9  265   9  5   4.4   2.4 |   1.0  33.8  285  12  6   0.6   0.3
 10750   0.9  33.6  265   8  4   4.6   2.5 |   1.1  34.0  285  11  6   2.8   1.5
 10500   1.2  34.2  270   6  3   6.0   3.3 |   1.2  34.2  285  10  5  -0.3  -0.2
 10250   1.8  35.2  280   5  2   8.2   4.5 |   1.0  33.8  290   9  5  -1.9  -1.0
 10000   2.4  36.3  295   4  2   8.3   4.6 |   1.0  33.8  290   8  4   0.2   0.1
  9750   3.0  37.4  315   3  2   8.0   4.4 |   1.0  33.8  295   7  4  -0.1  -0.0
  9500   3.6  38.5  340   3  2   9.2   5.1 |   0.9  33.6  300   6  3   0.6   0.4
  9250   4.4  39.9  350   4  2  10.5   5.8 |   1.1  34.0  310   5  3   2.8   1.5
  9000   5.1  41.2  355   4  2   9.4   5.1 |   1.4  34.5  325   5  2   5.6   3.1
  8750   5.8  42.4  360   4  2   8.3   4.6 |   1.8  35.2  340   5  2   6.3   3.4
  8500   6.4  43.5  005   4  2  10.0   5.5 |   2.3  36.1  350   5  3   7.8   4.3
  8250   7.3  45.1  005   4  2  12.2   6.7 |   3.0  37.4  355   5  3   9.7   5.3
  8000   8.1  46.6  010   4  2   9.2   5.1 |   3.7  38.7  360   5  3   8.9   4.9
  7750   8.8  47.8  010   4  2  12.3   6.8 |   4.4  39.9  005   5  3   9.6   5.3
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC).  It is not continuously monitored nor updated after its initial
issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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