Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261327
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0627 MST Monday, January 26, 2015

This forecast is for Monday, January 26, 2015:

If the trigger temperature of 55.2 F/12.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 407 ft/min (2.1 m/s)
   Maximum height of thermals.................. 12239 ft MSL (5481 ft AGL)

Forecast maximum temperature................... 61.0 F/16.6 C
Time of trigger temperature.................... 1045 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................. 10813 ft MSL (4055 ft AGL)
Thermal soaring outlook for Tuesday 01/27...... Good

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

Remarks...

Sunrise/Sunset.................... 07:10:07 / 17:12:01 MST
Total possible sunshine........... 10 hr 1 min 55 sec (601 min 55 sec)
Altitude of sun at 12:11:26 MST... 32.46 degrees

Upper air data from numerical model forecast valid on 01/26/2015 at 0500 MST

Freezing level.................. 6841 ft MSL (83 ft AGL)
Additional freezing level....... 12917 ft MSL (6159 ft AGL)
Convective condensation level... 19102 ft MSL (12344 ft AGL)
Lifted condensation level....... 15463 ft MSL (8705 ft AGL)
Lifted index.................... +3.9
K index......................... -1.9

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  -63.4 -82.1   325   34   17   2.3   1.2      M     M       M      M    M
 45000  -60.5 -76.9   335   45   23  -1.9  -1.0      M     M       M      M    M
 40000  -63.3 -81.9   335   25   13  -2.8  -1.5      M     M       M      M    M
 38000  -59.5 -75.1   335   27   14   7.5   4.1      M     M       M      M    M
 36000  -55.0 -67.0   330   30   16   7.5   4.1      M     M       M      M    M
 34000  -50.0 -58.0   335   34   18   9.0   4.9      M     M       M      M    M
 32000  -44.6 -48.3   340   39   20   9.0   4.9      M     M       M      M    M
 30000  -39.3 -38.7   345   40   21   8.7   4.8   30.5  87.0    11.1      M    M
 29000  -36.7 -34.1   345   40   20   8.7   4.8   30.1  86.2    10.9      M    M
 28000  -34.2 -29.6   345   39   20   8.7   4.8   29.8  85.6    10.8      M    M
 27000  -31.1 -24.0   340   39   20   8.1   4.4   29.1  84.4    10.4      M    M
 26000  -28.6 -19.5   340   40   20   8.1   4.4   28.4  83.2    10.0      M    M
 25000  -26.2 -15.2   335   40   21   8.1   4.4   27.9  82.2     9.6      M    M
 24000  -23.7 -10.7   335   39   20   8.5   4.7   27.4  81.3     9.3      M    M
 23000  -21.2  -6.2   330   36   18   8.5   4.7   26.9  80.4     9.0      M    M
 22000  -18.7  -1.7   325   33   17   8.5   4.7   26.5  79.7     8.8      M    M
 21000  -16.2   2.8   325   30   16   8.4   4.6   26.0  78.8     8.4      M    M
 20000  -13.7   7.3   325   27   14   8.4   4.6   25.5  78.0     8.1      M    M
 19500  -12.4   9.7   330   26   13   8.3   4.5   25.3  77.6     8.0      M    M
 19000  -11.2  11.8   330   24   13   6.8   3.7   25.1  77.2     7.8      M    M
 18500  -10.4  13.3   340   26   14   5.4   3.0   24.4  75.9     7.2      M    M
 18000   -9.6  14.7   350   29   15   5.2   2.8   23.6  74.5     6.6      M    M
 17500   -8.7  16.3   360   32   16   6.8   3.7   23.0  73.4     6.0      M    M
 17000   -7.7  18.1   360   33   17   6.6   3.6   22.5  72.4     5.6      M    M
 16500   -6.7  19.9   005   35   18   7.0   3.9   22.0  71.5     5.2      M    M
 16000   -5.7  21.7   010   36   19   7.3   4.0   21.5  70.8     4.8      M    M
 15500   -4.6  23.7   010   37   19   7.1   3.9   21.2  70.1     4.4      M    M
 15000   -3.6  25.5   010   37   19   6.3   3.4   20.6  69.1     4.0      M    M
 14500   -2.7  27.1   010   38   19   6.4   3.5   20.1  68.1     3.4      M    M
 14000   -1.9  28.6   010   37   19   5.3   2.9   19.4  67.0     2.8      M    M
 13500   -0.7  30.7   010   37   19   5.2   2.9   18.4  65.1     1.9      M    M
 13000    0.0  32.0   010   36   19   4.6   2.5   17.6  63.7     1.1      M    M
 12500    0.7  33.3   010   36   18   3.7   2.0   16.8  62.3     0.4      M    M
 12000    1.1  34.0   010   35   18   2.7   1.5   15.7  60.2    -0.7    390  2.0
 11750    1.3  34.3   005   34   18   2.6   1.4   15.1  59.2    -1.3    377  1.9
 11500    1.5  34.7   005   34   17   3.0   1.6   14.6  58.2    -1.8    364  1.8
 11250    1.7  35.1   005   33   17   4.2   2.3   14.1  57.4    -2.3    350  1.8
 11000    2.0  35.6   360   31   16   4.3   2.4   13.7  56.6    -2.8    333  1.7
 10750    2.2  36.0   360   30   16   3.6   2.0   13.2  55.8    -3.3    318  1.6
 10500    2.5  36.5   360   29   15   4.7   2.6   12.8  55.0    -3.7    303  1.5
 10250    2.9  37.2   360   29   15   7.0   3.9   12.5  54.5    -4.1    284  1.4
 10000    3.5  38.3   355   29   15   7.9   4.3   12.3  54.2    -4.2    260  1.3
  9750    4.0  39.2   355   29   15   7.6   4.2   12.2  53.9    -4.4    235  1.2
  9500    4.6  40.3   355   29   15   7.8   4.3   12.0  53.6    -4.6    211  1.1
  9250    5.2  41.4   355   29   15   8.2   4.5   11.9  53.4    -4.7    186  0.9
  9000    5.8  42.4   355   28   14   7.9   4.3   11.7  53.1    -4.9    160  0.8
  8750    6.4  43.5   355   27   14   9.4   5.1   11.6  52.9    -5.0    134  0.7
  8500    7.1  44.8   355   26   13   5.5   3.0   11.6  52.8    -5.1    107  0.5
  8250    7.2  45.0   350   24   12  -1.8  -1.0   10.9  51.6    -5.7     97  0.5
  8000    7.3  45.1   345   22   11   8.5   4.7   10.2  50.4    -6.4     87  0.4
  7750    7.3  45.1   340   20   11 -25.5 -14.0    9.6  49.3    -7.0     77  0.4
  7500    3.9  39.0   335   19   10 -39.8 -21.9    5.6  42.1   -11.1    174  0.9
  7250    2.4  36.3   325   16    8 -10.5  -5.7    3.8  38.8   -12.9    210  1.1
  7000    1.0  33.8   315   13    7 -35.5 -19.5    1.9  35.5   -14.8    246  1.3
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/26/2015 at 0800 MST          |       01/26/2015 at 1100 MST
                                           |
K index... -4.1  LI... +5.0                | K index... -2.9  LI... +4.7
CAPE... 0.0  CIN... M                      | 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 -64.0 -83.2  325  39 20   3.3   1.8 | -65.6 -86.1  330  39 20   3.8   2.1
 45000 -59.8 -75.6  340  43 22  -2.4  -1.3 | -60.8 -77.4  335  36 18  -1.8  -1.0
 40000 -63.6 -82.5  285  29 15  -3.2  -1.7 | -63.9 -83.0  295  35 18  -1.8  -1.0
 38000 -59.9 -75.8  290  31 16   7.3   4.0 | -59.9 -75.8  295  36 18   7.6   4.2
 36000 -55.5 -67.9  300  34 17   7.3   4.0 | -55.3 -67.5  290  36 19   7.6   4.2
 34000 -50.5 -58.9  315  34 18   9.1   5.0 | -50.2 -58.4  295  35 18   9.1   5.0
 32000 -45.0 -49.0  325  34 18   9.1   5.0 | -44.7 -48.5  295  32 16   9.1   5.0
 30000 -39.6 -39.3  335  34 18   9.0   5.0 | -39.4 -38.9  305  27 14   8.8   4.8
 29000 -36.9 -34.4  340  34 18   9.0   5.0 | -36.7 -34.1  315  25 13   8.8   4.8
 28000 -34.2 -29.6  345  35 18   9.0   5.0 | -34.1 -29.4  320  22 12   8.8   4.8
 27000 -31.5 -24.7  350  34 18   8.6   4.7 | -31.4 -24.5  330  21 11   9.0   4.9
 26000 -29.0 -20.2  350  34 17   8.6   4.7 | -28.7 -19.7  335  21 11   9.0   4.9
 25000 -25.7 -14.3  350  33 17   8.7   4.8 | -25.4 -13.7  345  22 11   9.2   5.0
 24000 -23.6 -10.5  350  31 16   6.3   3.5 | -23.3  -9.9  345  21 11   6.2   3.4
 23000 -21.7  -7.1  345  29 15   6.3   3.5 | -21.4  -6.5  345  21 11   6.2   3.4
 22000 -19.8  -3.6  340  27 14   6.0   3.3 | -19.6  -3.3  350  20 10   6.1   3.3
 21000 -17.4   0.7  335  24 12   8.8   4.9 | -17.3   0.9  340  18  9   8.1   4.5
 20000 -14.8   5.4  335  20 10   8.8   4.8 | -14.9   5.2  330  15  8   8.1   4.5
 19500 -13.4   7.9  335  18  9   8.9   4.9 | -13.7   7.3  320  15  8   8.1   4.4
 19000 -12.2  10.0  335  17  9   7.3   4.0 | -12.4   9.7  320  14  7   8.7   4.8
 18500 -11.2  11.8  340  20 10   6.8   3.7 | -11.1  12.0  325  15  8   8.7   4.8
 18000 -10.2  13.6  350  24 12   6.8   3.7 |  -9.8  14.4  330  16  8   8.2   4.5
 17500  -9.1  15.6  355  27 14   7.1   3.9 |  -8.8  16.2  340  19 10   5.9   3.3
 17000  -8.1  17.4  360  29 15   7.1   3.9 |  -7.9  17.8  350  22 11   6.0   3.3
 16500  -7.0  19.4  360  32 16   6.6   3.6 |  -7.0  19.4  355  25 13   6.4   3.5
 16000  -6.1  21.0  005  33 17   6.6   3.6 |  -6.0  21.2  360  27 14   6.4   3.5
 15500  -5.1  22.8  010  34 17   6.6   3.6 |  -5.1  22.8  005  29 15   6.6   3.6
 15000  -4.1  24.6  010  34 18   6.6   3.6 |  -4.1  24.6  010  29 15   6.7   3.7
 14500  -3.1  26.4  015  34 18   6.6   3.6 |  -3.1  26.4  010  30 15   6.8   3.7
 14000  -2.2  28.0  015  33 17   6.6   3.6 |  -2.1  28.2  015  30 15   6.8   3.7
 13500  -1.2  29.8  015  32 17   6.7   3.7 |  -1.1  30.0  015  29 15   6.9   3.8
 13000  -0.2  31.6  010  31 16   6.5   3.6 |  -0.1  31.8  015  29 15   7.4   4.1
 12500   0.7  33.3  010  30 15   7.0   3.8 |   1.0  33.8  015  28 15   7.4   4.1
 12000   1.4  34.5  010  29 15   3.4   1.9 |   2.0  35.6  015  28 14   5.9   3.2
 11750   1.7  35.1  005  29 15   5.0   2.7 |   2.4  36.3  015  28 14   6.4   3.5
 11500   2.1  35.8  005  29 15   4.7   2.6 |   2.9  37.2  015  27 14   6.3   3.4
 11250   2.4  36.3  005  29 15   4.3   2.3 |   3.4  38.1  015  27 14   6.1   3.3
 11000   2.7  36.9  005  28 14   3.5   1.9 |   3.8  38.8  010  26 14   5.5   3.0
 10750   2.9  37.2  005  27 14   3.7   2.0 |   4.2  39.6  010  25 13   5.1   2.8
 10500   3.1  37.6  360  26 13   3.1   1.7 |   4.5  40.1  010  25 13   4.9   2.7
 10250   3.4  38.1  360  25 13   5.0   2.8 |   4.9  40.8  005  24 12   5.6   3.1
 10000   3.9  39.0  360  24 12   7.1   3.9 |   5.3  41.5  005  23 12   6.4   3.5
  9750   4.8  40.6  355  23 12   5.8   3.2 |   6.1  43.0  360  21 11   4.7   2.6
  9500   5.2  41.4  355  22 11   7.4   4.1 |   6.5  43.7  355  20 10   6.3   3.4
  9250   5.8  42.4  355  21 11   8.5   4.7 |   7.0  44.6  355  19 10   7.3   4.0
  9000   6.5  43.7  355  21 11   8.4   4.6 |   7.5  45.5  355  18  9   6.5   3.6
  8750   7.1  44.8  355  20 10   7.1   3.9 |   7.9  46.2  355  16  8   5.2   2.8
  8500   7.5  45.5  350  19 10   3.4   1.9 |   8.3  46.9  350  15  8   5.0   2.7
  8250   7.7  45.9  345  17  9   2.9   1.6 |   8.7  47.7  345  14  7   5.2   2.8
  8000   7.9  46.2  340  16  8   0.4   0.2 |   9.0  48.2  335  13  7   5.3   2.9
  7750   7.0  44.6  335  16  8 -31.4 -17.2 |   8.9  48.0  325  13  7 -13.6  -7.5
  7500   2.9  37.2  320  12  6 -70.2 -38.5 |   6.4  43.5  315  10  5 -44.5 -24.4
  7250  -0.3  31.5  295  10  5  23.9  13.1 |   4.0  39.2  295   8  4  12.6   6.9
  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

           01/26/2015 at 1400 MST          |       01/26/2015 at 1700 MST
                                           |
K index... -2.8  LI... +3.9                | K index... -3.7  LI... +3.2
CAPE... 0.0  CIN... -0.3                   | 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 -65.1 -85.2  325  36 18   4.5   2.5 | -64.9 -84.8  320  36 18   4.8   2.6
 45000 -59.4 -74.9  320  36 18  -2.2  -1.2 | -58.8 -73.8  320  36 19  -2.0  -1.1
 40000 -63.3 -81.9  300  39 20  -3.3  -1.8 | -61.7 -79.1  310  38 19  -2.8  -1.5
 38000 -59.7 -75.5  295  38 20   7.0   3.9 | -58.7 -73.7  305  38 20   6.2   3.4
 36000 -55.5 -67.9  290  37 19   7.0   3.9 | -54.9 -66.8  300  39 20   6.2   3.4
 34000 -50.6 -59.1  290  37 19   8.9   4.9 | -50.5 -58.9  295  38 20   8.5   4.7
 32000 -45.3 -49.5  290  37 19   8.9   4.9 | -45.4 -49.7  290  37 19   8.5   4.7
 30000 -39.9 -39.8  290  32 16   9.0   5.0 | -40.2 -40.4  290  33 17   8.8   4.8
 29000 -37.2 -35.0  290  28 14   9.0   5.0 | -36.9 -34.4  290  29 15   8.8   4.8
 28000 -34.5 -30.1  295  23 12   9.0   5.0 | -34.3 -29.7  285  26 14   8.8   4.8
 27000 -31.7 -25.1  300  21 11   9.3   5.1 | -31.6 -24.9  290  24 12   9.1   5.0
 26000 -28.2 -18.8  305  20 10   9.3   5.1 | -28.9 -20.0  295  21 11   9.1   5.0
 25000 -25.4 -13.7  305  19 10   9.5   5.2 | -26.1 -15.0  305  19 10   9.1   5.0
 24000 -23.2  -9.8  315  17  9   6.5   3.6 | -23.8 -10.8  315  16  8   7.0   3.8
 23000 -21.3  -6.3  330  16  8   6.5   3.6 | -21.7  -7.1  330  13  7   6.9   3.8
 22000 -19.3  -2.7  345  17  9   6.5   3.5 | -19.6  -3.3  350  12  6   6.9   3.8
 21000 -17.2   1.0  350  15  8   7.3   4.0 | -17.5   0.5  360  11  6   7.3   4.0
 20000 -15.0   5.0  345  14  7   7.3   4.0 | -15.3   4.5  360  10  5   7.3   4.0
 19500 -14.0   6.8  345  13  6   7.2   4.0 | -14.2   6.4  355  10  5   7.4   4.0
 19000 -12.8   9.0  345  12  6   9.1   5.0 | -13.1   8.4  355   9  5   8.3   4.5
 18500 -11.4  11.5  340  12  6   9.4   5.2 | -11.8  10.8  355   9  5   8.8   4.8
 18000 -10.0  14.0  335  12  6   9.0   5.0 | -10.5  13.1  350   9  5   8.9   4.9
 17500  -8.8  16.2  340  13  7   7.2   3.9 |  -9.2  15.4  350   9  5   8.0   4.4
 17000  -7.7  18.1  350  15  8   7.4   4.0 |  -8.0  17.6  350  10  5   8.2   4.5
 16500  -6.7  19.9  355  17  9   6.1   3.4 |  -6.8  19.8  350  11  6   7.2   3.9
 16000  -5.8  21.6  360  20 10   6.1   3.4 |  -5.8  21.6  355  13  6   6.9   3.8
 15500  -4.9  23.2  005  22 11   6.6   3.6 |  -4.8  23.4  360  14  7   7.0   3.8
 15000  -3.9  25.0  005  23 12   7.0   3.9 |  -3.7  25.3  360  14  7   7.3   4.0
 14500  -2.8  27.0  010  23 12   7.1   3.9 |  -2.1  28.2  010  15  8   7.4   4.0
 14000  -1.8  28.8  010  24 12   7.0   3.9 |  -1.0  30.2  010  15  8   7.4   4.0
 13500  -0.7  30.7  010  23 12   7.0   3.9 |   0.0  32.0  010  15  8   7.0   3.9
 13000   0.2  32.4  015  23 12   6.4   3.5 |   1.0  33.8  015  14  7   6.6   3.6
 12500   1.2  34.2  015  22 11   6.5   3.5 |   2.0  35.6  015  14  7   6.7   3.7
 12000   2.1  35.8  015  21 11   6.3   3.5 |   2.9  37.2  015  12  6   6.0   3.3
 11750   2.6  36.7  015  21 11   6.6   3.6 |   3.4  38.1  015  12  6   6.2   3.4
 11500   3.1  37.6  015  20 11   6.8   3.7 |   3.8  38.8  015  11  6   5.9   3.2
 11250   3.6  38.5  015  20 10   5.7   3.1 |   4.2  39.6  015  10  5   5.4   3.0
 11000   4.0  39.2  015  19 10   5.1   2.8 |   4.6  40.3  015   9  5   5.5   3.0
 10750   4.4  39.9  020  19 10   6.0   3.3 |   5.1  41.2  015   9  4   5.5   3.0
 10500   4.8  40.6  020  19 10   5.9   3.2 |   5.5  41.9  010   8  4   5.8   3.2
 10250   5.3  41.5  020  18  9   6.6   3.6 |   5.9  42.6  010   7  4   6.3   3.5
 10000   6.3  43.3  015  16  8   6.2   3.4 |   6.4  43.5  005   6  3   6.2   3.4
  9750   6.7  44.1  010  15  8   5.2   2.8 |   6.8  44.2  360   5  3   5.6   3.1
  9500   7.1  44.8  010  14  7   6.8   3.7 |   7.2  45.0  355   4  2   6.3   3.5
  9250   7.7  45.9  005  13  7   7.7   4.2 |   7.7  45.9  350   4  2   7.3   4.0
  9000   8.2  46.8  005  12  6   7.0   3.9 |   8.3  46.9  340   3  2   7.2   3.9
  8750   8.7  47.7  005  11  6   6.3   3.5 |   8.8  47.8  330   3  1   8.7   4.8
  8500   9.2  48.6  355  10  5   6.9   3.8 |   9.5  49.1  315   2  1   8.5   4.7
  8250   9.7  49.5  345   9  5   6.6   3.6 |  10.0  50.0  295   3  2   5.9   3.2
  8000  10.2  50.4  335   8  4   9.1   5.0 |  10.5  50.9  280   4  2  10.1   5.5
  7750  10.6  51.1  320   8  4  -3.1  -1.7 |  11.0  51.8  275   5  2  -4.0  -2.2
  7500   8.9  48.0  305   7  4 -30.8 -16.9 |   9.7  49.5  270   6  3 -17.6  -9.7
  7250   7.2  45.0  290   6  3  19.2  10.5 |   8.6  47.5  275   6  3 -12.2  -6.7
  7000     M     M    M   M  M     M     M |   7.5  45.5  275   6  3 -17.3  -9.5
  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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