Soaring Guidance
Issued by NWS Denver/Boulder, CO

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686
UXUS97 KBOU 110026
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1726 MST Wednesday, February 10, 2016

This forecast is for Thursday, February 11, 2016:

If the trigger temperature of 60.0 F/15.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 530 ft/min (2.7 m/s)
   Maximum height of thermals.................. 11683 ft MSL (6376 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1315 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................. 6682 ft MSL (1376 ft AGL)
Thermal soaring outlook for Friday 02/12....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 20838 ft MSL (15531 ft AGL)
Wave soaring outlook for Friday 02/12.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:57:10 / 17:29:19 MST
Total possible sunshine........... 10 hr 32 min 10 sec (632 min 10 sec)
Altitude of sun at 12:13:34 MST... 36.26 degrees

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

Freezing level.................. 5403 ft MSL (96 ft AGL)
Additional freezing level....... 10696 ft MSL (5389 ft AGL)
Convective condensation level... 20272 ft MSL (14965 ft AGL)
Lifted condensation level....... 16903 ft MSL (11596 ft AGL)
Lifted index.................... +6.7
K index......................... -6.7

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  -60.2 -76.4   300   42   21   2.1   1.1      M     M       M      M    M
 45000  -57.1 -70.8   310   53   27  -0.8  -0.5      M     M       M      M    M
 40000  -61.0 -77.8   315   61   31  -2.6  -1.4      M     M       M      M    M
 38000  -60.4 -76.7   320   63   33   4.3   2.3      M     M       M      M    M
 36000  -57.5 -71.5   330   67   35   4.3   2.4      M     M       M      M    M
 34000  -54.3 -65.7   335   69   36   7.3   4.0      M     M       M      M    M
 32000  -49.9 -57.8   340   68   35   7.3   4.0      M     M       M      M    M
 30000  -45.1 -49.2   340   67   34   9.2   5.1   29.9  85.7     9.9      M    M
 29000  -42.4 -44.3   340   67   34   9.2   5.1   29.6  85.3     9.8      M    M
 28000  -39.6 -39.3   340   66   34   9.2   5.1   29.5  85.0     9.8      M    M
 27000  -36.8 -34.2   340   66   34   9.5   5.2   29.3  84.8     9.9      M    M
 26000  -34.0 -29.2   340   63   32   9.4   5.2   29.1  84.4     9.8      M    M
 25000  -31.2 -24.2   340   60   31   9.5   5.2   29.0  84.3     9.9      M    M
 24000  -28.4 -19.1   340   58   30   8.2   4.5   28.9  84.1     9.9      M    M
 23000  -26.0 -14.8   340   55   28   8.0   4.4   28.2  82.7     9.4      M    M
 22000  -23.6 -10.5   340   52   27   8.0   4.4   27.6  81.6     9.0      M    M
 21000  -21.3  -6.3   340   49   25   7.7   4.2   26.9  80.5     8.5      M    M
 20000  -19.0  -2.2   335   44   23   7.7   4.2   26.2  79.1     8.0      M    M
 19500  -17.8  -0.0   335   41   21   7.7   4.2   25.8  78.5     7.7      M    M
 19000  -16.6   2.1   330   39   20   7.8   4.3   25.5  77.9     7.5      M    M
 18500  -15.5   4.1   330   37   19   7.4   4.1   25.2  77.3     7.2      M    M
 18000  -13.8   7.2   330   36   19   7.6   4.1   24.5  76.2     6.7      M    M
 17500  -12.8   9.0   325   36   18   6.5   3.6   24.1  75.4     6.4      M    M
 17000  -11.8  10.8   325   35   18   6.6   3.6   23.5  74.4     5.9      M    M
 16500  -10.8  12.6   325   34   17   6.2   3.4   23.0  73.4     5.5      M    M
 16000   -9.9  14.2   320   32   17   6.0   3.3   22.4  72.2     4.9      M    M
 15500   -9.0  15.8   320   31   16   5.8   3.2   21.7  71.1     4.4      M    M
 15000   -8.2  17.2   315   28   15   5.0   2.8   21.0  69.7     3.8      M    M
 14500   -7.5  18.5   310   26   13   5.0   2.8   20.2  68.3     3.1      M    M
 14000   -6.7  19.9   310   24   12   4.9   2.7   19.4  66.9     2.4      M    M
 13500   -6.0  21.2   305   21   11   4.7   2.6   18.6  65.5     1.6      M    M
 13000   -5.2  22.6   305   18    9   6.7   3.7   17.9  64.3     1.0      M    M
 12500   -4.2  24.4   305   15    8   6.4   3.5   17.4  63.4     0.5      M    M
 12000   -3.1  26.4   310   13    7   8.4   4.6   17.0  62.6     0.1      M    M
 11500   -1.9  28.6   310   12    6   8.4   4.6   16.8  62.2    -0.1    508  2.6
 11000   -0.7  30.7   310   11    6   7.9   4.3   16.5  61.7    -0.4    457  2.3
 10500    0.5  32.9   310   10    5   8.9   4.9   16.2  61.2    -0.7    407  2.1
 10250    1.1  34.0   310    9    5   3.8   2.1   16.1  60.9    -0.8    382  1.9
 10000    1.3  34.3   310    9    4   6.1   3.3   15.5  59.9    -1.4    370  1.9
  9750    2.1  35.8   305    8    4  12.9   7.1   15.6  60.1    -1.3    337  1.7
  9500    3.0  37.4   305    8    4  11.1   6.1   15.7  60.3    -1.1    303  1.5
  9250    3.8  38.8   300    8    4   8.9   4.9   15.8  60.5    -1.1    272  1.4
  9000    4.3  39.7   300    7    4   8.0   4.4   15.7  60.2    -1.2    248  1.3
  8750    5.1  41.2   300    7    4  10.8   5.9   15.6  60.2    -1.2    218  1.1
  8500    5.9  42.6   300    7    4  10.7   5.9   15.7  60.3    -1.1    186  0.9
  8250    6.6  43.9   300    8    4   9.5   5.2   15.8  60.4    -1.1    156  0.8
  8000    7.3  45.1   305    9    5   8.9   4.9   15.7  60.3    -1.2    129  0.7
  7750    8.0  46.4   305   11    5  10.1   5.5   15.7  60.2    -1.2    100  0.5
  7500    8.7  47.7   305   12    6   7.0   3.9   15.7  60.2    -1.3     72  0.4
  7250    9.0  48.2   305   15    7   3.3   1.8   15.2  59.4    -1.7     55  0.3
  7000    9.3  48.7   300   17    9   5.0   2.8   14.8  58.7    -2.1     39  0.2
  6750    9.6  49.3   295   19   10   1.6   0.9   14.4  57.9    -2.6     23  0.1
  6500    9.3  48.7   290   20   10  -9.2  -5.0   13.4  56.1    -3.6     24  0.1
  6250    8.4  47.1   285   18    9 -12.5  -6.8   11.7  53.0    -5.3     45  0.2
  6000    7.4  45.3   280   16    8 -15.2  -8.4   10.0  50.0    -7.0     66  0.3
  5750    5.6  42.1   265   14    7 -35.5 -19.5    7.5  45.5    -9.6    114  0.6
  5500    2.0  35.6   245    9    4 -54.6 -29.9    3.2  37.8   -13.9    213  1.1

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

           02/11/2016 at 0800 MST          |       02/11/2016 at 1100 MST
                                           |
K index... -2.2  LI... +5.7                | K index... +3.7  LI... +4.8
CAPE... 0.0  CIN... -0.6                   | 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 -60.6 -77.1  305  42 22   1.6   0.9 | -60.5 -76.9  300  42 22   1.0   0.5
 45000 -58.2 -72.8  310  48 25  -0.2  -0.1 | -59.1 -74.4  305  48 24  -1.0  -0.5
 40000 -59.9 -75.8  320  55 28  -1.1  -0.6 | -61.8 -79.2  325  59 30  -1.8  -1.0
 38000 -59.3 -74.7  325  61 31   2.9   1.6 | -60.9 -77.6  330  61 32   4.3   2.4
 36000 -57.5 -71.5  330  69 36   2.9   1.6 | -58.3 -72.9  340  61 31   4.3   2.4
 34000 -54.5 -66.1  330  75 39   8.0   4.4 | -54.4 -65.9  345  62 32   8.7   4.8
 32000 -49.7 -57.5  335  74 38   8.0   4.4 | -49.2 -56.6  345  64 33   8.6   4.7
 30000 -44.9 -48.8  335  71 36   8.1   4.5 | -44.1 -47.4  345  66 34   8.7   4.8
 29000 -42.4 -44.3  335  68 35   8.1   4.5 | -41.4 -42.5  345  66 34   8.7   4.8
 28000 -40.0 -40.0  335  65 33   8.1   4.5 | -38.8 -37.8  345  67 35   8.7   4.8
 27000 -37.4 -35.3  335  62 32   9.5   5.2 | -36.2 -33.2  340  66 34   8.9   4.9
 26000 -34.6 -30.3  330  59 31   9.4   5.1 | -33.5 -28.3  335  62 32   8.9   4.9
 25000 -31.8 -25.2  330  57 29   9.4   5.1 | -30.9 -23.6  335  58 30   8.9   4.9
 24000 -29.1 -20.4  330  54 28   8.7   4.8 | -28.3 -18.9  330  55 28   8.0   4.4
 23000 -26.5 -15.7  330  50 26   8.7   4.8 | -25.9 -14.6  325  51 26   8.1   4.4
 22000 -23.9 -11.0  330  46 24   8.7   4.8 | -23.5 -10.3  325  48 25   8.1   4.4
 21000 -21.5  -6.7  330  43 22   6.9   3.8 | -21.2  -6.2  320  44 23   6.9   3.8
 20000 -19.4  -2.9  330  41 21   7.1   3.9 | -19.1  -2.4  315  40 21   7.0   3.8
 19500 -18.3  -0.9  330  40 20   7.1   3.9 | -18.1  -0.6  315  38 20   7.0   3.8
 19000 -17.3   0.9  335  39 20   7.2   3.9 | -17.1   1.2  310  36 19   7.2   4.0
 18500 -16.3   2.7  330  37 19   6.1   3.3 | -16.2   2.8  310  34 17   5.0   2.7
 18000 -15.4   4.3  330  35 18   6.1   3.4 | -15.4   4.3  305  32 16   5.2   2.9
 17500 -14.0   6.8  330  33 17   6.7   3.7 | -14.2   6.4  305  28 15   6.3   3.5
 17000 -13.0   8.6  330  32 17   6.7   3.7 | -13.3   8.1  310  27 14   6.1   3.4
 16500 -11.9  10.6  330  31 16   7.2   3.9 | -12.2  10.0  310  25 13   8.3   4.6
 16000 -10.8  12.6  330  30 15   7.4   4.1 | -10.9  12.4  315  25 13   8.9   4.9
 15500  -9.7  14.5  330  28 15   7.4   4.1 |  -9.5  14.9  320  25 13   8.5   4.7
 15000  -8.6  16.5  335  28 14   7.3   4.0 |  -8.3  17.1  320  25 13   7.7   4.2
 14500  -7.5  18.5  335  27 14   7.3   4.0 |  -7.2  19.0  320  25 13   7.8   4.3
 14000  -6.4  20.5  335  26 13   6.9   3.8 |  -6.0  21.2  325  25 13   8.4   4.6
 13500  -5.4  22.3  335  24 12   6.8   3.7 |  -4.7  23.5  325  25 13   8.4   4.6
 13000  -4.2  24.4  335  22 11   8.0   4.4 |  -3.5  25.7  330  25 13   7.4   4.1
 12500  -3.1  26.4  335  20 10   7.9   4.3 |  -2.4  27.7  330  24 13   7.4   4.1
 12000  -1.9  28.6  335  19 10   7.9   4.3 |  -1.2  29.8  335  24 12   8.7   4.8
 11500  -0.7  30.7  335  18  9   7.9   4.3 |   0.1  32.2  335  23 12   8.7   4.8
 11000   0.5  32.9  335  17  9   8.2   4.5 |   1.3  34.3  335  23 12   7.6   4.2
 10500   1.7  35.1  335  15  8   8.9   4.9 |   2.5  36.5  335  22 12   8.0   4.4
 10250   2.3  36.1  335  15  8   3.5   1.9 |   3.0  37.4  335  22 11   4.2   2.3
 10000   2.4  36.3  335  15  8   6.5   3.6 |   3.3  37.9  335  23 12   6.2   3.4
  9750   3.4  38.1  335  15  8  13.7   7.5 |   4.0  39.2  335  23 12  11.2   6.1
  9500   4.3  39.7  335  15  8  11.6   6.3 |   4.8  40.6  330  24 12   9.4   5.2
  9250   5.1  41.2  335  16  8   9.5   5.2 |   5.4  41.7  330  24 12   6.4   3.5
  9000   5.7  42.3  335  16  8   8.5   4.7 |   5.8  42.4  330  24 13   5.2   2.8
  8750   6.4  43.5  335  17  9  10.6   5.8 |   6.3  43.3  325  25 13   7.7   4.2
  8500   7.2  45.0  330  18  9   9.6   5.3 |   6.9  44.4  325  25 13   6.4   3.5
  8250   7.8  46.0  325  19 10   7.4   4.1 |   7.2  45.0  320  26 13   3.8   2.1
  8000   8.4  47.1  320  21 11   6.7   3.7 |   7.5  45.5  315  26 13   3.2   1.8
  7750   8.8  47.8  315  22 12   6.7   3.7 |   7.7  45.9  315  27 14   2.9   1.6
  7500   9.3  48.7  310  24 13   3.5   1.9 |   7.9  46.2  310  27 14   1.1   0.6
  7250   9.3  48.7  305  25 13   0.9   0.5 |   7.8  46.0  305  25 13   0.1   0.1
  7000   9.4  48.9  300  25 13   2.2   1.2 |   7.8  46.0  305  23 12   0.5   0.3
  6750   9.5  49.1  295  26 14  -0.3  -0.2 |   7.8  46.0  300  21 11   0.7   0.4
  6500   9.2  48.6  290  25 13  -8.8  -4.9 |   7.8  46.0  300  18  9  -1.3  -0.7
  6250   8.3  46.9  290  21 11 -10.9  -6.0 |   7.6  45.7  300  14  7  -1.5  -0.8
  6000   7.5  45.5  285  17  9 -15.2  -8.3 |   7.4  45.3  300   9  5  -5.7  -3.1
  5750   5.5  41.9  270  13  7 -37.1 -20.3 |   6.4  43.5  280   6  3 -20.1 -11.0
  5500   1.9  35.4  250   8  4 -55.2 -30.3 |   4.3  39.7  240   4  2 -29.0 -15.9

           02/11/2016 at 1400 MST          |       02/11/2016 at 1700 MST
                                           |
K index... +7.5  LI... +4.2                | K index... +8.8  LI... +4.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -60.3 -76.5  300  44 23   0.5   0.3 | -59.9 -75.8  300  44 23   1.3   0.7
 45000 -59.7 -75.5  300  49 25  -2.0  -1.1 | -58.0 -72.4  305  54 28  -3.0  -1.7
 40000 -64.0 -83.2  320  59 30  -2.9  -1.6 | -65.3 -85.5  320  56 29  -4.9  -2.7
 38000 -62.8 -81.0  325  60 31   5.8   3.2 | -64.1 -83.4  325  56 29   7.0   3.8
 36000 -59.3 -74.7  325  58 30   5.8   3.2 | -59.9 -75.8  325  53 27   7.0   3.8
 34000 -55.3 -67.5  325  56 29   8.8   4.9 | -54.5 -66.1  320  51 26   9.7   5.3
 32000 -49.2 -56.6  325  57 29   8.9   4.9 | -48.7 -55.7  315  52 27   9.7   5.3
 30000 -43.9 -47.0  325  56 29   8.8   4.9 | -43.2 -45.8  315  53 27   8.7   4.8
 29000 -41.2 -42.2  325  55 28   8.8   4.9 | -40.6 -41.1  315  53 27   8.7   4.8
 28000 -38.6 -37.5  325  53 27   8.9   4.9 | -38.0 -36.4  315  53 27   8.7   4.8
 27000 -35.9 -32.6  325  52 27   8.9   4.9 | -35.4 -31.7  315  52 27   8.8   4.8
 26000 -33.3 -27.9  320  49 25   8.9   4.9 | -32.7 -26.9  315  49 25   8.8   4.8
 25000 -30.6 -23.1  320  47 24   8.9   4.9 | -30.1 -22.2  315  46 24   8.8   4.8
 24000 -28.0 -18.4  320  44 23   7.8   4.3 | -27.5 -17.5  315  43 22   8.4   4.6
 23000 -25.7 -14.3  315  41 21   7.9   4.3 | -25.0 -13.0  310  38 20   8.4   4.6
 22000 -23.3  -9.9  310  38 19   7.9   4.4 | -22.5  -8.5  305  34 18   8.4   4.6
 21000 -21.0  -5.8  305  35 18   7.5   4.1 | -20.1  -4.2  305  32 16   7.2   4.0
 20000 -18.8  -1.8  310  35 18   7.6   4.2 | -17.9  -0.2  305  32 16   7.3   4.0
 19500 -17.6   0.3  310  35 18   7.6   4.2 | -16.8   1.8  310  32 16   7.3   4.0
 19000 -16.5   2.3  310  34 18   7.6   4.2 | -15.8   3.6  310  32 16   7.3   4.0
 18500 -15.4   4.3  310  34 18   7.6   4.2 | -14.7   5.5  315  33 17   7.3   4.0
 18000 -14.3   6.3  310  35 18   7.6   4.2 | -13.6   7.5  315  34 18   7.4   4.0
 17500 -13.1   8.4  310  35 18   7.6   4.2 | -12.5   9.5  320  36 18   7.2   4.0
 17000 -11.5  11.3  310  35 18   7.5   4.1 | -10.9  12.4  320  36 19   7.2   3.9
 16500 -10.3  13.5  310  34 18   7.5   4.1 |  -9.9  14.2  320  37 19   7.2   3.9
 16000  -9.2  15.4  315  34 17   7.5   4.1 |  -8.8  16.2  320  37 19   7.2   3.9
 15500  -8.1  17.4  315  34 17   7.5   4.1 |  -7.8  18.0  320  37 19   7.1   3.9
 15000  -7.0  19.4  315  33 17   7.5   4.1 |  -6.7  19.9  320  36 19   7.1   3.9
 14500  -5.9  21.4  315  33 17   7.5   4.1 |  -5.7  21.7  320  35 18   7.0   3.8
 14000  -4.8  23.4  320  33 17   7.4   4.1 |  -4.7  23.5  320  34 18   6.5   3.6
 13500  -3.7  25.3  320  32 17   7.4   4.1 |  -3.7  25.3  320  33 17   6.5   3.6
 13000  -2.6  27.3  325  32 16   7.3   4.0 |  -2.7  27.1  320  32 17   6.7   3.7
 12500  -1.5  29.3  325  31 16   7.3   4.0 |  -1.7  28.9  320  31 16   6.8   3.7
 12000  -0.4  31.3  325  30 15   7.0   3.8 |  -0.7  30.7  320  30 15   5.9   3.3
 11500   0.7  33.3  325  29 15   7.1   3.9 |   0.2  32.4  320  28 15   6.1   3.3
 11000   1.7  35.1  325  28 14   5.8   3.2 |   1.0  33.8  320  27 14   5.8   3.2
 10500   2.6  36.7  320  27 14   6.5   3.6 |   1.9  35.4  315  26 14   6.4   3.5
 10250   3.0  37.4  320  26 14   2.6   1.4 |   2.4  36.3  315  26 13   2.7   1.5
 10000   3.1  37.6  320  26 13   4.2   2.3 |   2.5  36.5  315  26 13   4.1   2.3
  9750   3.7  38.7  320  26 14   9.0   4.9 |   3.1  37.6  310  26 13   8.7   4.8
  9500   4.3  39.7  320  27 14   7.5   4.1 |   3.6  38.5  310  26 13   7.4   4.0
  9250   4.8  40.6  315  27 14   4.6   2.5 |   4.1  39.4  305  26 13   4.6   2.5
  9000   5.1  41.2  315  27 14   2.7   1.5 |   4.4  39.9  305  26 13   3.2   1.8
  8750   5.3  41.5  310  27 14   3.9   2.1 |   4.7  40.5  300  25 13   5.0   2.8
  8500   5.6  42.1  310  27 14   3.8   2.1 |   5.1  41.2  295  24 12   5.3   2.9
  8250   5.9  42.6  305  26 13   3.8   2.1 |   5.5  41.9  295  23 12   5.6   3.1
  8000   6.1  43.0  305  24 12   3.8   2.1 |   5.9  42.6  290  20 10   5.6   3.1
  7750   6.4  43.5  305  22 11   5.9   3.2 |   6.3  43.3  290  18  9   6.3   3.5
  7500   6.9  44.4  305  20 10   5.6   3.1 |   6.7  44.1  285  16  8   4.8   2.7
  7250   7.2  45.0  305  17  9   3.9   2.1 |   7.0  44.6  285  13  7   3.2   1.8
  7000   7.5  45.5  310  15  8   4.5   2.5 |   7.2  45.0  280  10  5   3.6   2.0
  6750   7.8  46.0  315  12  6   3.8   2.1 |   7.5  45.5  275   8  4   3.5   1.9
  6500   8.0  46.4  315   9  5   2.0   1.1 |   7.8  46.0  265   5  3   5.2   2.8
  6250   8.1  46.6  320   6  3   1.9   1.1 |   8.2  46.8  245   4  2   6.6   3.6
  6000   8.2  46.8  335   3  1   0.1   0.1 |   8.7  47.7  210   4  2   5.1   2.8
  5750   7.8  46.0  085   1  0  -9.6  -5.2 |   8.6  47.5  185   4  2  -7.6  -4.2
  5500   6.4  43.5  145   2  1 -19.2 -10.5 |   7.1  44.8  185   4  2 -24.8 -13.6
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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