Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261302
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0602 MST Wednesday, February 26, 2020

This forecast is for Wednesday, February 26, 2020:

If the trigger temperature of 23.5 F/-4.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 507 ft/min (2.6 m/s)
   Maximum height of thermals.................. 14837 ft MSL (7234 ft AGL)

Forecast maximum temperature................... 38.0 F/3.8 C
Time of trigger temperature.................... 1015 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................. 13686 ft MSL (6083 ft AGL)
Thermal soaring outlook for Thursday 02/27..... Good

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

Remarks...

Sunrise/Sunset.................... 06:36:18 / 17:48:06 MST
Total possible sunshine........... 11 hr 11 min 48 sec (671 min 48 sec)
Altitude of sun at 12:12:12 MST... 42.23 degrees

Upper air data from numerical model forecast valid on 02/26/2020 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 21180 ft MSL (13577 ft AGL)
Lifted condensation level....... 18252 ft MSL (10649 ft AGL)
Lifted index.................... +8.3
K index......................... -28.2

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  -54.3 -65.7   305   20   10   1.2   0.7      M     M       M      M    M
 45000  -52.5 -62.5   310   27   14   1.2   0.6      M     M       M      M    M
 40000  -55.8 -68.4   310   26   13  -2.7  -1.5      M     M       M      M    M
 38000  -57.3 -71.1   315   25   13   0.3   0.2      M     M       M      M    M
 36000  -57.1 -70.8   325   25   13   0.2   0.1      M     M       M      M    M
 34000  -57.0 -70.6   335   25   13  -0.3  -0.2      M     M       M      M    M
 32000  -53.9 -65.0   340   27   14   5.8   3.2      M     M       M      M    M
 30000  -50.4 -58.7   345   30   15   6.2   3.4      M     M       M      M    M
 29000  -48.2 -54.8   345   30   15   7.6   4.2   18.1  64.5    11.4      M    M
 28000  -45.9 -50.6   350   30   16   7.6   4.2   17.2  63.0    10.8      M    M
 27000  -43.6 -46.5   350   31   16   7.6   4.2   16.5  61.6    10.4      M    M
 26000  -41.3 -42.3   355   31   16   8.0   4.4   15.7  60.3     9.9      M    M
 25000  -38.9 -38.0   355   31   16   8.0   4.4   15.0  59.0     9.5      M    M
 24000  -36.5 -33.7   355   32   16   8.0   4.4   14.4  58.0     9.1      M    M
 23000  -34.2 -29.6   355   32   16   7.6   4.2   13.7  56.7     8.7      M    M
 22000  -31.3 -24.3   355   32   16   7.6   4.2   12.7  54.9     7.9      M    M
 21000  -29.1 -20.4   360   31   16   7.6   4.1   12.1  53.7     7.4      M    M
 20000  -26.8 -16.2   360   30   16   7.4   4.1   11.2  52.1     6.8      M    M
 19500  -25.7 -14.3   355   30   15   7.4   4.1   10.8  51.4     6.5      M    M
 19000  -24.6 -12.3   355   30   15   7.4   4.1   10.4  50.7     6.2      M    M
 18500  -23.5 -10.3   355   29   15   7.2   4.0   10.1  50.1     5.9      M    M
 18000  -22.5  -8.5   355   29   15   5.8   3.2    9.5  49.1     5.4      M    M
 17500  -21.6  -6.9   355   28   15   6.0   3.3    8.8  47.9     4.9      M    M
 17000  -20.8  -5.4   355   28   14   4.5   2.5    8.1  46.6     4.3      M    M
 16500  -20.2  -4.4   355   27   14   4.3   2.4    7.2  44.9     3.5      M    M
 16000  -19.5  -3.1   350   26   13   3.1   1.7    6.3  43.3     2.7      M    M
 15500  -19.2  -2.6   350   24   13   2.2   1.2    5.0  41.0     1.5      M    M
 15000  -18.9  -2.0   350   23   12   1.9   1.0    3.8  38.8     0.4      M    M
 14500  -18.7  -1.7   350   22   11   1.2   0.7    2.4  36.3    -0.9    493  2.5
 14000  -18.5  -1.3   345   21   11   1.3   0.7    1.0  33.8    -2.2    473  2.4
 13500  -18.3  -0.9   345   19   10   1.7   0.9   -0.3  31.4    -3.4    452  2.3
 13000  -18.1  -0.6   345   17    9   1.9   1.0   -1.6  29.1    -4.7    430  2.2
 12500  -17.6   0.3   340   15    8   3.7   2.0   -2.7  27.2    -5.7    402  2.0
 12000  -17.2   1.0   340   14    7   2.5   1.3   -3.8  25.2    -6.9    376  1.9
 11750  -17.0   1.4   340   13    7   4.0   2.2   -4.3  24.2    -7.4    361  1.8
 11500  -16.7   1.9   340   12    6   4.7   2.6   -4.7  23.5    -7.8    344  1.7
 11250  -16.3   2.7   340   12    6   4.0   2.2   -5.1  22.8    -8.2    327  1.7
 11000  -16.0   3.2   340   12    6   4.2   2.3   -5.6  21.9    -8.7    311  1.6
 10750  -15.7   3.7   340   11    6   5.3   2.9   -6.0  21.2    -9.1    293  1.5
 10500  -15.3   4.5   335   11    6   4.8   2.6   -6.3  20.6    -9.5    274  1.4
 10250  -14.9   5.2   335   11    6   6.9   3.8   -6.7  20.0    -9.8    255  1.3
 10000  -14.3   6.3   335   11    6   8.0   4.4   -6.8  19.8   -10.0    229  1.2
  9750  -13.8   7.2   335   12    6   6.7   3.7   -7.0  19.4   -10.2    206  1.0
  9500  -13.3   8.1   330   12    6   7.1   3.9   -7.2  19.0   -10.5    183  0.9
  9250  -12.7   9.1   330   12    6   6.9   3.8   -7.4  18.6   -10.7    160  0.8
  9000  -12.3   9.9   330   12    6   5.5   3.0   -7.7  18.1   -11.0    138  0.7
  8750  -11.9  10.6   325   12    6   4.4   2.4   -8.1  17.4   -11.4    121  0.6
  8500  -11.6  11.1   320   11    6   5.0   2.7   -8.5  16.7   -11.8    103  0.5
  8250  -11.2  11.8   315   11    5   2.8   1.5   -8.9  16.0   -12.3     85  0.4
  8000  -11.5  11.3   310   10    5 -13.0  -7.1   -9.9  14.2   -13.3     86  0.4
  7750  -13.3   8.1   305    7    4 -33.3 -18.3  -12.4   9.6   -15.9    133  0.7
  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 * * * * * *

           02/26/2020 at 0800 MST          |       02/26/2020 at 1100 MST
                                           |
CAPE...     0.0    LI...       +5.8        | CAPE...     0.0    LI...       +4.0
CINH...     0.0    K Index... -12.1        | CINH...     0.0    K Index...  -6.7
                                           |
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 -54.3 -65.7  300  20 10   1.3   0.7 | -54.1 -65.4  290  17  9   1.1   0.6
 45000 -52.4 -62.3  310  23 12   1.2   0.7 | -52.5 -62.5  295  20 10   1.1   0.6
 40000 -54.6 -66.3  310  26 14  -1.8  -1.0 | -53.7 -64.7  305  25 13  -1.1  -0.6
 38000 -55.8 -68.4  310  27 14  -2.3  -1.3 | -54.8 -66.6  305  27 14  -4.4  -2.4
 36000 -57.2 -71.0  310  24 13  -2.3  -1.3 | -57.4 -71.3  310  26 13  -4.3  -2.4
 34000 -58.6 -73.5  315  22 11  -3.1  -1.7 | -60.0 -76.0  320  25 13  -5.1  -2.8
 32000 -55.7 -68.3  325  23 12   5.9   3.2 | -56.6 -69.9  325  25 13   6.8   3.7
 30000 -52.1 -61.8  335  25 13   6.6   3.6 | -52.6 -62.7  325  26 13   7.4   4.0
 29000 -49.6 -57.3  340  25 13   8.6   4.7 | -50.1 -58.2  330  25 13   8.4   4.6
 28000 -47.0 -52.6  340  25 13   8.6   4.7 | -47.6 -53.7  330  25 13   8.4   4.6
 27000 -44.5 -48.1  345  26 13   8.6   4.7 | -45.0 -49.0  330  24 12   8.4   4.6
 26000 -41.9 -43.4  345  26 13   8.5   4.6 | -42.5 -44.5  330  23 12   8.7   4.8
 25000 -39.4 -38.9  345  26 13   8.4   4.6 | -39.9 -39.8  330  23 12   8.7   4.8
 24000 -36.9 -34.4  350  26 14   8.4   4.6 | -37.2 -35.0  335  22 12   8.7   4.8
 23000 -33.9 -29.0  350  27 14   7.6   4.2 | -34.0 -29.2  335  22 11   8.6   4.7
 22000 -31.6 -24.9  350  27 14   7.7   4.2 | -31.4 -24.5  335  22 12   8.6   4.7
 21000 -29.3 -20.7  350  27 14   7.6   4.2 | -28.9 -20.0  340  22 12   7.8   4.3
 20000 -27.0 -16.6  350  27 14   7.6   4.2 | -26.7 -16.1  340  22 11   7.3   4.0
 19500 -25.9 -14.6  350  27 14   7.6   4.2 | -25.6 -14.1  340  22 11   7.3   4.0
 19000 -24.7 -12.5  355  27 14   7.6   4.2 | -24.5 -12.1  340  22 11   7.3   4.0
 18500 -23.6 -10.5  355  27 14   7.6   4.2 | -23.4 -10.1  340  22 11   7.4   4.1
 18000 -22.4  -8.3  355  27 14   7.6   4.2 | -22.3  -8.1  340  21 11   7.5   4.1
 17500 -21.3  -6.3  355  26 14   7.6   4.2 | -21.2  -6.2  340  21 11   7.5   4.1
 17000 -20.2  -4.4  355  26 13   7.5   4.1 | -20.0  -4.0  345  21 11   7.7   4.3
 16500 -19.1  -2.4  355  26 13   7.6   4.2 | -18.9  -2.0  345  21 11   7.8   4.3
 16000 -18.0  -0.4  355  26 13   5.8   3.2 | -17.8  -0.0  345  21 11   7.2   3.9
 15500 -17.2   1.0  350  25 13   5.3   2.9 | -16.7   1.9  345  21 11   7.1   3.9
 15000 -16.4   2.5  350  24 13   4.2   2.3 | -15.7   3.7  345  20 10   6.3   3.4
 14500 -15.9   3.4  350  24 12   3.0   1.6 | -14.8   5.4  345  20 10   5.8   3.2
 14000 -15.5   4.1  350  23 12   2.4   1.3 | -13.9   7.0  345  20 10   4.8   2.6
 13500 -15.2   4.6  350  21 11   1.3   0.7 | -13.4   7.9  345  20 10   3.6   2.0
 13000 -15.0   5.0  345  20 10   1.0   0.5 | -12.8   9.0  345  19 10   2.5   1.4
 12500 -15.0   5.0  345  18  9   0.1   0.1 | -12.7   9.1  340  18  9   1.0   0.6
 12000 -15.0   5.0  345  16  8   1.1   0.6 | -12.4   9.7  340  17  9   2.2   1.2
 11750 -14.8   5.4  345  15  8   2.8   1.5 | -12.2  10.0  340  16  8   2.6   1.4
 11500 -14.6   5.7  345  14  7   3.5   1.9 | -12.0  10.4  340  14  7   2.3   1.3
 11250 -14.4   6.1  345  13  7   1.9   1.0 | -11.8  10.8  340  13  7   3.4   1.8
 11000 -14.3   6.3  345  12  6   3.0   1.6 | -11.5  11.3  340  12  6   4.3   2.3
 10750 -13.9   7.0  345  11  6   5.6   3.1 | -11.2  11.8  340  11  6   4.1   2.3
 10500 -13.5   7.7  345  10  5   5.9   3.3 | -10.9  12.4  335  10  5   3.8   2.1
 10250 -13.1   8.4  345   9  5   3.8   2.1 | -10.6  12.9  335   9  5   5.2   2.9
 10000 -12.9   8.8  345   9  4   3.8   2.1 | -10.1  13.8  335   8  4   6.5   3.5
  9750 -12.5   9.5  340   8  4   6.0   3.3 |  -9.7  14.5  330   7  3   5.8   3.2
  9500 -12.0  10.4  340   8  4   5.6   3.1 |  -9.3  15.3  320   6  3   6.4   3.5
  9250 -11.6  11.1  335   7  4   5.2   2.8 |  -8.8  16.2  310   5  3   4.7   2.6
  9000 -11.2  11.8  335   7  4   5.7   3.1 |  -8.5  16.7  305   5  2   7.5   4.1
  8750 -10.8  12.6  330   7  4   6.6   3.6 |  -7.7  18.1  295   4  2  11.1   6.1
  8500 -10.3  13.5  330   8  4   6.6   3.6 |  -6.9  19.6  285   4  2  10.4   5.7
  8250  -9.9  14.2  325   8  4   1.3   0.7 |  -6.2  20.8  270   3  2   8.9   4.9
  8000 -10.2  13.6  320   8  4  -7.0  -3.9 |  -5.5  22.1  265   3  2  12.1   6.6
  7750 -10.8  12.6  305   5  3  -8.0  -4.4 |  -4.2  24.4  265   3  1  22.0  12.1
  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

           02/26/2020 at 1400 MST          |       02/26/2020 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.5        | CAPE...     0.0    LI...       +1.3
CINH...     0.0    K Index...  +6.2        | CINH...     0.0    K Index... +12.5
                                           |
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 -54.4 -65.9  285  20 10   0.5   0.3 | -54.7 -66.5  295  19 10   0.1   0.1
 45000 -53.7 -64.7  295  24 12   0.5   0.3 | -54.6 -66.3  305  24 12   0.1   0.0
 40000 -54.6 -66.3  300  27 14  -0.7  -0.4 | -55.3 -67.5  310  26 14  -0.6  -0.3
 38000 -55.3 -67.5  305  27 14  -2.9  -1.6 | -55.7 -68.3  310  27 14  -1.1  -0.6
 36000 -57.0 -70.6  310  27 14  -2.9  -1.6 | -56.4 -69.5  320  29 15  -1.1  -0.6
 34000 -58.8 -73.8  310  27 14  -3.5  -1.9 | -57.1 -70.8  325  32 16  -0.9  -0.5
 32000 -56.2 -69.2  310  26 14   5.2   2.9 | -54.0 -65.2  320  31 16   5.7   3.1
 30000 -53.0 -63.4  305  26 13   6.4   3.5 | -50.6 -59.1  320  29 15   6.0   3.3
 29000 -50.5 -58.9  310  25 13   8.6   4.7 | -48.7 -55.7  320  28 15   6.5   3.5
 28000 -47.9 -54.2  310  25 13   8.6   4.7 | -46.7 -52.1  315  27 14   6.5   3.5
 27000 -45.4 -49.7  310  24 12   8.6   4.7 | -44.8 -48.6  315  27 14   6.5   3.6
 26000 -42.8 -45.0  310  24 12   8.6   4.7 | -42.6 -44.7  315  26 13   7.8   4.3
 25000 -40.2 -40.4  315  23 12   8.6   4.7 | -40.3 -40.5  310  24 12   7.9   4.3
 24000 -37.6 -35.7  315  22 11   8.6   4.7 | -37.9 -36.2  310  23 12   7.9   4.3
 23000 -34.4 -29.9  315  21 11   8.6   4.7 | -35.0 -31.0  310  22 12   7.5   4.1
 22000 -31.8 -25.2  315  21 11   8.6   4.7 | -32.8 -27.0  310  22 11   7.5   4.1
 21000 -29.3 -20.7  315  20 10   8.1   4.4 | -30.5 -22.9  315  22 11   7.6   4.2
 20000 -27.0 -16.6  315  20 10   7.7   4.2 | -28.2 -18.8  315  22 11   7.7   4.3
 19500 -25.8 -14.4  315  19 10   7.7   4.2 | -27.1 -16.8  315  22 11   7.8   4.3
 19000 -24.7 -12.5  320  19 10   7.7   4.2 | -25.9 -14.6  320  22 11   7.8   4.3
 18500 -23.5 -10.3  320  19 10   7.4   4.0 | -24.8 -12.6  320  22 11   7.8   4.3
 18000 -22.5  -8.5  320  19 10   7.0   3.9 | -23.6 -10.5  320  21 11   7.8   4.3
 17500 -21.5  -6.7  320  18  9   7.0   3.8 | -22.5  -8.5  320  21 11   7.8   4.3
 17000 -20.4  -4.7  320  18  9   7.1   3.9 | -21.4  -6.5  320  21 11   7.5   4.1
 16500 -19.4  -2.9  320  18  9   7.1   3.9 | -20.2  -4.4  320  21 11   7.6   4.2
 16000 -18.3  -0.9  320  17  9   6.5   3.6 | -19.2  -2.6  325  20 10   7.0   3.8
 15500 -17.4   0.7  320  17  9   6.5   3.5 | -18.1  -0.6  320  20 10   6.9   3.8
 15000 -16.4   2.5  320  17  9   6.2   3.4 | -17.1   1.2  320  19 10   6.9   3.8
 14500 -15.5   4.1  320  16  8   6.1   3.3 | -16.1   3.0  320  18  9   6.9   3.8
 14000 -14.6   5.7  320  15  8   5.6   3.1 | -15.1   4.8  320  17  9   7.1   3.9
 13500 -13.8   7.2  320  15  8   5.2   2.8 | -14.0   6.8  320  16  8   7.3   4.0
 13000 -13.0   8.6  320  14  7   5.4   3.0 | -12.9   8.8  315  15  8   8.0   4.4
 12500 -12.2  10.0  320  13  7   6.0   3.3 | -11.6  11.1  315  14  7   8.5   4.7
 12000 -11.3  11.7  315  12  6   6.1   3.4 | -10.4  13.3  310  14  7   8.5   4.6
 11750 -10.8  12.6  315  11  6   6.3   3.5 |  -9.7  14.5  310  13  7   9.3   5.1
 11500 -10.3  13.5  315  11  6   6.4   3.5 |  -9.0  15.8  310  12  6   9.3   5.1
 11250  -9.8  14.4  310  10  5   8.5   4.7 |  -8.3  17.1  305  11  6  10.2   5.6
 11000  -9.1  15.6  310   9  5   8.2   4.5 |  -7.6  18.3  305  10  5   8.9   4.9
 10750  -8.6  16.5  305   8  4   6.8   3.7 |  -7.0  19.4  300   9  5   7.4   4.0
 10500  -8.1  17.4  305   7  4   6.2   3.4 |  -6.5  20.3  300   8  4   6.5   3.5
 10250  -7.6  18.3  300   7  3   9.8   5.4 |  -5.9  21.4  295   7  4  10.7   5.8
 10000  -6.7  19.9  300   6  3  10.3   5.7 |  -5.0  23.0  295   7  4  10.2   5.6
  9750  -6.2  20.8  295   5  2   6.8   3.7 |  -4.5  23.9  290   6  3   5.3   2.9
  9500  -5.6  21.9  290   4  2   8.1   4.5 |  -4.0  24.8  285   5  3   7.3   4.0
  9250  -5.0  23.0  275   3  1   6.5   3.5 |  -3.5  25.7  280   5  2   4.2   2.3
  9000  -4.6  23.7  265   2  1   8.1   4.4 |  -3.3  26.1  270   4  2   4.4   2.4
  8750  -3.8  25.2  255   2  1  10.6   5.8 |  -2.8  27.0  255   4  2   7.1   3.9
  8500  -3.1  26.4  245   2  1  10.0   5.5 |  -2.3  27.9  240   3  2   6.5   3.6
  8250  -2.3  27.9  225   1  1   9.9   5.5 |  -1.9  28.6  220   3  2   6.2   3.4
  8000  -1.5  29.3  225   1  1  12.1   6.6 |  -1.5  29.3  210   3  2   4.3   2.3
  7750  -0.5  31.1  215   1  1  16.3   8.9 |  -1.3  29.7  195   2  1   2.9   1.6
  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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