Soaring Guidance
Issued by NWS Pueblo, CO

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418
UXUS97 KPUB 111224
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0524 MST Thursday, February 11, 2016

This forecast is for Thursday, February 11, 2016:

If the trigger temperature of 54.5 F/12.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 154 ft/min (0.8 m/s)
   Maximum height of thermals.................. 9138 ft MSL (2380 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 C
Time of trigger temperature.................... None
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................. 7811 ft MSL (1053 ft AGL)
Thermal soaring outlook for Friday 02/12....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:55:20 / 17:30:13 MST
Total possible sunshine........... 10 hr 34 min 52 sec (634 min 52 sec)
Altitude of sun at 12:13:06 MST... 37.07 degrees

Upper air data from numerical model forecast valid on 02/11/2016 at 0500 MST

Freezing level.................. 7033 ft MSL (275 ft AGL)
Additional freezing level....... 11526 ft MSL (4768 ft AGL)
Convective condensation level... 20117 ft MSL (13359 ft AGL)
Lifted condensation level....... 16612 ft MSL (9854 ft AGL)
Lifted index.................... +5.9
K index......................... -3.7

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  -60.8 -77.4   300   41   21   2.7   1.5      M     M       M      M    M
 45000  -56.8 -70.2   305   51   26  -0.8  -0.4      M     M       M      M    M
 40000  -61.4 -78.5   320   53   27  -3.0  -1.6      M     M       M      M    M
 38000  -60.2 -76.4   330   53   27   4.7   2.6      M     M       M      M    M
 36000  -57.4 -71.3   340   55   28   4.7   2.6      M     M       M      M    M
 34000  -54.0 -65.2   350   58   30   7.4   4.1      M     M       M      M    M
 32000  -49.6 -57.3   350   59   30   7.5   4.1      M     M       M      M    M
 30000  -44.8 -48.6   350   56   29   9.0   4.9   24.8  76.6    10.0      M    M
 29000  -42.1 -43.8   350   50   26   9.0   4.9   24.4  75.9     9.9      M    M
 28000  -39.4 -38.9   345   45   23   9.0   4.9   24.1  75.4     9.8      M    M
 27000  -36.1 -33.0   340   41   21   8.6   4.7   23.8  74.8     9.6      M    M
 26000  -33.5 -28.3   340   40   21   8.6   4.7   23.3  73.9     9.4      M    M
 25000  -31.0 -23.8   340   40   20   8.7   4.7   22.9  73.3     9.2      M    M
 24000  -28.4 -19.1   335   39   20   8.5   4.7   22.6  72.6     9.0      M    M
 23000  -25.8 -14.4   340   40   20   8.5   4.7   22.0  71.7     8.7      M    M
 22000  -23.3  -9.9   340   40   20   8.5   4.7   21.7  71.0     8.4      M    M
 21000  -20.9  -5.6   340   39   20   7.2   3.9   21.0  69.8     8.0      M    M
 20000  -18.8  -1.8   335   35   18   7.2   3.9   20.1  68.2     7.2      M    M
 19500  -17.8  -0.0   335   34   17   7.2   3.9   19.7  67.4     6.9      M    M
 19000  -16.7   1.9   335   32   17   7.2   3.9   19.3  66.7     6.6      M    M
 18500  -15.6   3.9   330   31   16   7.2   3.9   18.8  65.9     6.2      M    M
 18000  -14.5   5.9   330   30   16   7.2   3.9   18.4  65.1     5.9      M    M
 17500  -13.5   7.7   330   29   15   7.1   3.9   18.0  64.4     5.5      M    M
 17000  -12.4   9.7   330   29   15   7.1   3.9   17.5  63.6     5.1      M    M
 16500  -11.3  11.7   330   28   14   7.2   4.0   17.1  62.8     4.8      M    M
 16000  -10.2  13.6   330   27   14   7.4   4.1   16.7  62.1     4.5      M    M
 15500   -9.1  15.6   325   26   13   7.4   4.1   16.3  61.4     4.1      M    M
 15000   -8.0  17.6   325   24   13   7.3   4.0   15.9  60.7     3.8      M    M
 14500   -6.9  19.6   325   23   12   7.3   4.0   15.5  60.0     3.5      M    M
 14000   -5.3  22.5   320   21   11   7.4   4.0   15.0  58.9     2.9      M    M
 13500   -4.2  24.4   320   20   10   7.4   4.0   14.6  58.2     2.6      M    M
 13000   -3.1  26.4   320   19   10   7.5   4.1   14.2  57.6     2.2      M    M
 12500   -2.0  28.4   315   18    9   7.5   4.1   13.8  56.9     1.9      M    M
 12000   -0.9  30.4   315   16    8   7.6   4.2   13.5  56.3     1.5      M    M
 11750   -0.3  31.5   315   16    8   7.6   4.2   13.3  56.0     1.4      M    M
 11500    0.2  32.4   315   15    8   7.6   4.2   13.2  55.7     1.2      M    M
 11250    0.8  33.4   315   15    8   7.4   4.1   13.0  55.4     1.1      M    M
 11000    1.4  34.5   315   14    7   8.0   4.4   12.8  55.1     0.9      M    M
 10750    2.0  35.6   320   13    7   8.6   4.7   12.7  54.9     0.8      M    M
 10500    2.6  36.7   320   13    7   8.4   4.6   12.6  54.7     0.7      M    M
 10250    3.2  37.8   325   12    6   7.4   4.1   12.5  54.5     0.6      M    M
 10000    3.7  38.7   325   12    6   7.5   4.1   12.3  54.1     0.4      M    M
  9750    4.4  39.9   325   11    6   9.1   5.0   12.2  53.9     0.2      M    M
  9500    5.0  41.0   325   11    6   8.9   4.9   12.1  53.9     0.2      M    M
  9250    5.6  42.1   325   11    6   7.4   4.1   12.0  53.6     0.1      M    M
  9000    6.1  43.0   320   11    6   6.5   3.6   11.8  53.2    -0.2    139  0.7
  8750    6.6  43.9   320   11    6   7.8   4.3   11.6  52.9    -0.4    116  0.6
  8500    7.2  45.0   315   12    6   4.1   2.3   11.4  52.5    -0.6     94  0.5
  8250    7.1  44.8   310   12    6  -3.0  -1.7   10.6  51.1    -1.3     87  0.4
  8000    6.9  44.4   305   13    6  -0.7  -0.4    9.7  49.4    -2.3     86  0.4
  7750    6.7  44.1   305   13    7 -11.6  -6.4    8.7  47.7    -3.3     86  0.4
  7500    4.9  40.8   290   14    7 -31.5 -17.3    6.3  43.3    -5.8    133  0.7
  7250    2.3  36.1   290   12    6 -35.1 -19.3    3.4  38.1    -8.7    203  1.0
  7000   -0.3  31.5   285   10    5 -33.2 -18.2    0.5  32.9   -11.7    274  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           02/11/2016 at 0800 MST          |       02/11/2016 at 1100 MST
                                           |
K index... -1.6  LI... +277.6              | K index... +2.3  LI... +278.0
CAPE... 0.0  CIN... -0.0                   | 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 -61.1 -78.0  300  41 21   1.8   1.0 | -60.8 -77.4  300  43 22   1.4   0.8
 45000 -58.6 -73.5  305  53 27  -1.7  -0.9 | -58.8 -73.8  305  48 24  -2.1  -1.2
 40000 -62.8 -81.0  320  53 27  -2.8  -1.5 | -63.5 -82.3  320  52 27  -3.2  -1.7
 38000 -61.5 -78.7  325  53 28   5.6   3.1 | -62.4 -80.3  325  52 27   5.5   3.0
 36000 -58.1 -72.6  335  55 28   5.6   3.1 | -59.1 -74.4  330  52 27   5.5   3.0
 34000 -53.8 -64.8  340  58 30   8.1   4.5 | -54.6 -66.3  335  53 27   9.0   4.9
 32000 -48.9 -56.0  335  58 30   8.1   4.5 | -49.2 -56.6  340  55 28   8.9   4.9
 30000 -43.9 -47.0  335  56 29   8.6   4.7 | -43.8 -46.8  335  55 28   9.1   5.0
 29000 -41.3 -42.3  330  54 28   8.6   4.7 | -41.0 -41.8  335  53 27   9.1   5.0
 28000 -38.7 -37.7  330  51 26   8.6   4.7 | -38.3 -36.9  335  52 27   9.1   5.0
 27000 -36.1 -33.0  330  49 25   9.1   5.0 | -35.6 -32.1  330  51 26   8.7   4.7
 26000 -33.4 -28.1  330  48 25   9.0   5.0 | -33.0 -27.4  325  50 26   8.7   4.8
 25000 -30.6 -23.1  330  47 24   9.0   5.0 | -30.4 -22.7  320  50 26   8.7   4.8
 24000 -28.0 -18.4  330  45 23   8.4   4.6 | -27.8 -18.0  320  49 25   8.5   4.7
 23000 -25.4 -13.7  325  40 21   8.4   4.6 | -25.3 -13.5  320  47 24   8.6   4.7
 22000 -22.9  -9.2  325  36 18   8.4   4.6 | -22.7  -8.9  315  45 23   8.6   4.7
 21000 -20.5  -4.9  320  32 16   7.4   4.0 | -20.2  -4.4  315  42 22   7.9   4.3
 20000 -18.3  -0.9  315  28 14   7.4   4.1 | -17.9  -0.2  310  37 19   7.9   4.3
 19500 -17.2   1.0  310  26 13   7.4   4.1 | -16.7   1.9  305  34 18   7.9   4.3
 19000 -16.1   3.0  310  24 12   7.4   4.1 | -15.5   4.1  305  32 16   7.9   4.3
 18500 -15.0   5.0  305  23 12   7.9   4.3 | -14.4   6.1  300  31 16   7.2   3.9
 18000 -13.8   7.2  310  24 12   7.8   4.3 | -13.3   8.1  300  30 15   7.3   4.0
 17500 -12.6   9.3  310  24 13   7.2   3.9 | -12.3   9.9  300  29 15   6.5   3.6
 17000 -11.6  11.1  315  24 12   6.8   3.7 | -11.4  11.5  300  27 14   6.2   3.4
 16500 -10.6  12.9  315  24 12   6.7   3.7 | -10.0  14.0  300  25 13   6.2   3.4
 16000  -9.2  15.4  320  23 12   6.4   3.5 |  -9.0  15.8  305  23 12   6.3   3.4
 15500  -8.2  17.2  320  22 11   6.4   3.5 |  -8.1  17.4  305  21 11   6.4   3.5
 15000  -7.2  19.0  325  21 11   6.4   3.5 |  -7.1  19.2  305  19 10   6.5   3.6
 14500  -6.2  20.8  325  20 10   6.4   3.5 |  -6.1  21.0  310  17  9   6.7   3.7
 14000  -5.3  22.5  325  19 10   6.7   3.7 |  -5.0  23.0  310  15  8   7.6   4.1
 13500  -4.2  24.4  325  18 10   6.7   3.7 |  -3.9  25.0  315  13  7   7.6   4.2
 13000  -3.1  26.4  330  18  9   7.9   4.3 |  -2.6  27.3  320  13  7   8.7   4.8
 12500  -2.0  28.4  330  18  9   7.4   4.0 |  -1.4  29.5  330  13  7   9.0   5.0
 12000  -0.7  30.7  335  18  9   9.4   5.2 |   0.0  32.0  335  14  7   9.3   5.1
 11750  -0.1  31.8  335  18  9   9.1   5.0 |   0.7  33.3  340  14  7   9.3   5.1
 11500   0.6  33.1  340  18  9   9.3   5.1 |   1.4  34.5  340  15  8   9.3   5.1
 11250   1.3  34.3  340  18  9   8.4   4.6 |   2.1  35.8  345  15  8   9.3   5.1
 11000   1.9  35.4  345  18  9   8.8   4.8 |   2.8  37.0  345  15  8   9.4   5.2
 10750   2.6  36.7  345  18  9   9.8   5.4 |   3.6  38.5  345  16  8   9.5   5.2
 10500   3.4  38.1  345  18  9   9.7   5.3 |   4.3  39.7  345  17  9   9.4   5.2
 10250   4.1  39.4  345  19 10   8.5   4.7 |   5.0  41.0  345  17  9   9.0   5.0
 10000   4.7  40.5  345  19 10   7.9   4.3 |   5.6  42.1  345  18  9   8.8   4.8
  9750   5.3  41.5  345  19 10   8.9   4.9 |   6.3  43.3  345  19 10   9.0   5.0
  9500   6.0  42.8  340  20 10   8.7   4.8 |   7.0  44.6  340  20 10   8.7   4.8
  9250   6.6  43.9  340  21 11   7.4   4.0 |   7.6  45.7  340  21 11   7.3   4.0
  9000   7.1  44.8  335  21 11   6.5   3.6 |   8.1  46.6  335  21 11   6.6   3.6
  8750   7.5  45.5  330  21 11   6.3   3.4 |   8.5  47.3  330  21 11   5.6   3.1
  8500   7.8  46.0  325  22 11   1.6   0.9 |   8.8  47.8  325  21 11   0.7   0.4
  8250   7.7  45.9  320  22 11  -4.8  -2.6 |   8.6  47.5  315  21 11  -3.6  -2.0
  8000   7.2  45.0  315  22 11  -4.6  -2.5 |   8.2  46.8  310  21 11  -5.1  -2.8
  7750   6.8  44.2  310  22 11  -9.6  -5.3 |   7.8  46.0  305  20 11  -1.3  -0.7
  7500   5.4  41.7  300  21 11 -25.5 -14.0 |   7.5  45.5  300  19 10 -10.6  -5.8
  7250   3.1  37.6  300  17  9 -32.7 -18.0 |   5.9  42.6  295  16  8 -23.1 -12.7
  7000   0.7  33.3  295  13  7 -27.6 -15.2 |   4.3  39.7  295  12  6 -13.0  -7.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/11/2016 at 1400 MST          |       02/11/2016 at 1700 MST
                                           |
K index... +15.0  LI... +275.1             | K index... +12.7  LI... +275.1
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.2 -76.4  300  41 21   1.7   0.9 | -60.1 -76.2  295  44 23   1.9   1.0
 45000 -57.8 -72.0  305  48 25  -1.8  -1.0 | -57.5 -71.5  300  47 24  -3.4  -1.8
 40000 -63.4 -82.1  320  52 27  -3.5  -1.9 | -64.4 -83.9  320  54 28  -4.7  -2.6
 38000 -62.0 -79.6  325  52 27   5.4   3.0 | -63.2 -81.8  320  55 28   6.8   3.7
 36000 -58.7 -73.7  325  51 26   5.4   3.0 | -59.1 -74.4  320  55 28   6.8   3.7
 34000 -54.7 -66.5  330  50 26   9.1   5.0 | -54.6 -66.3  320  54 28   8.8   4.8
 32000 -49.3 -56.7  330  48 25   9.1   5.0 | -48.7 -55.7  325  53 27   8.9   4.9
 30000 -43.9 -47.0  330  47 24   9.0   5.0 | -43.4 -46.1  325  51 26   8.8   4.8
 29000 -41.2 -42.2  330  46 24   9.0   5.0 | -40.7 -41.3  325  48 25   8.8   4.8
 28000 -38.5 -37.3  330  45 23   9.0   5.0 | -38.1 -36.6  320  46 24   8.8   4.8
 27000 -35.1 -31.2  330  44 23   8.9   4.9 | -35.5 -31.9  320  43 22   8.6   4.7
 26000 -32.5 -26.5  325  42 21   8.9   4.9 | -32.9 -27.2  320  41 21   8.6   4.7
 25000 -29.8 -21.6  320  40 21   8.9   4.9 | -30.3 -22.5  315  38 20   8.6   4.7
 24000 -27.3 -17.1  320  38 20   8.0   4.4 | -27.8 -18.0  315  36 18   7.5   4.1
 23000 -24.9 -12.8  320  36 19   8.1   4.4 | -25.6 -14.1  310  33 17   7.6   4.2
 22000 -22.5  -8.5  315  34 18   8.0   4.4 | -23.3  -9.9  310  30 15   7.6   4.2
 21000 -20.3  -4.5  315  33 17   6.4   3.5 | -21.0  -5.8  310  28 15   7.8   4.3
 20000 -18.5  -1.3  315  31 16   6.4   3.5 | -18.7  -1.7  315  29 15   7.8   4.3
 19500 -17.5   0.5  315  30 16   6.4   3.5 | -17.5   0.5  315  29 15   7.8   4.3
 19000 -16.6   2.1  315  30 15   6.4   3.5 | -16.4   2.5  320  29 15   7.8   4.3
 18500 -15.7   3.7  320  28 15   6.2   3.4 | -15.2   4.6  320  29 15   8.0   4.4
 18000 -14.7   5.5  320  27 14   6.2   3.4 | -14.0   6.8  325  29 15   8.0   4.4
 17500 -13.8   7.2  320  25 13   7.1   3.9 | -12.8   9.0  325  30 15   8.0   4.4
 17000 -12.7   9.1  320  24 12   7.3   4.0 | -11.6  11.1  325  31 16   8.0   4.4
 16500 -11.6  11.1  325  23 12   7.4   4.1 | -10.5  13.1  325  31 16   7.8   4.3
 16000 -10.5  13.1  325  22 11   7.7   4.2 |  -8.8  16.2  330  32 16   7.2   3.9
 15500  -9.3  15.3  325  21 11   7.7   4.2 |  -7.8  18.0  330  32 16   7.1   3.9
 15000  -8.1  17.4  330  20 10   8.7   4.8 |  -6.8  19.8  330  32 16   7.1   3.9
 14500  -6.8  19.8  330  19 10   8.6   4.7 |  -5.7  21.7  330  32 16   7.2   4.0
 14000  -4.9  23.2  330  19 10   8.9   4.9 |  -4.6  23.7  330  31 16   7.7   4.2
 13500  -3.5  25.7  330  19 10   8.9   4.9 |  -3.5  25.7  325  30 16   7.6   4.2
 13000  -2.2  28.0  335  20 10   9.2   5.1 |  -2.4  27.7  325  29 15   7.0   3.9
 12500  -0.8  30.6  335  22 11   9.8   5.4 |  -1.4  29.5  325  27 14   7.8   4.3
 12000   0.5  32.9  335  24 12   8.3   4.5 |  -0.2  31.6  320  24 12   7.0   3.8
 11750   1.2  34.2  335  24 13   8.6   4.7 |   0.3  32.5  320  23 12   7.3   4.0
 11500   1.8  35.2  335  25 13   8.6   4.7 |   0.9  33.6  315  21 11   7.2   4.0
 11250   2.5  36.5  335  26 13   8.9   4.9 |   1.5  34.7  310  19 10   8.2   4.5
 11000   3.1  37.6  335  26 13   8.6   4.7 |   2.1  35.8  305  17  9   7.6   4.2
 10750   3.7  38.7  335  26 13   8.2   4.5 |   2.6  36.7  300  16  8   6.5   3.5
 10500   4.4  39.9  335  26 13   8.2   4.5 |   3.1  37.6  295  14  7   6.8   3.7
 10250   4.9  40.8  335  25 13   7.2   4.0 |   3.6  38.5  290  14  7   7.3   4.0
 10000   5.5  41.9  335  23 12   6.6   3.6 |   4.2  39.6  290  13  7   7.1   3.9
  9750   6.0  42.8  330  21 11   6.8   3.8 |   4.7  40.5  290  13  7   6.1   3.3
  9500   6.5  43.7  330  19 10   6.4   3.5 |   5.1  41.2  290  13  7   6.2   3.4
  9250   6.9  44.4  325  18  9   5.1   2.8 |   5.6  42.1  290  13  7   7.1   3.9
  9000   7.3  45.1  325  17  9   4.5   2.5 |   6.1  43.0  285  12  6   7.3   4.0
  8750   7.6  45.7  325  16  8   4.7   2.6 |   6.7  44.1  285  12  6   7.6   4.2
  8500   7.9  46.2  320  15  8   3.4   1.9 |   7.2  45.0  285  12  6   5.9   3.3
  8250   8.0  46.4  320  15  8   2.1   1.2 |   7.5  45.5  285  11  6   4.1   2.2
  8000   8.1  46.6  315  14  7   1.8   1.0 |   7.7  45.9  285  10  5   3.5   1.9
  7750   8.2  46.8  315  14  7   3.6   2.0 |   7.9  46.2  285   9  5   6.2   3.4
  7500   8.0  46.4  310  12  6  -9.1  -5.0 |   8.0  46.4  280   7  4  -8.6  -4.7
  7250   6.6  43.9  310  10  5 -22.3 -12.3 |   6.4  43.5  285   7  3 -25.1 -13.8
  7000   5.1  41.2  305   8  4 -12.0  -6.6 |   4.9  40.8  290   6  3 -12.4  -6.8
  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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