Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 270133
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1933 MDT Wednesday, August 26, 2015

This forecast is for Thursday, August 27, 2015:

If the trigger temperature of 76.8 F/24.9 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 585 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14504 ft MSL (9197 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10982 ft MSL (5675 ft AGL)
Thermal soaring outlook for Friday 08/28....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT).........
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 25455 ft MSL (20148 ft AGL)
Wave soaring outlook for Friday 08/28.......... Poor

Remarks...

Sunrise/Sunset.................... 06:22:37 / 19:40:04 MDT
Total possible sunshine........... 13 hr 17 min 28 sec (797 min 28 sec)
Altitude of sun at 13:00:55 MDT... 60.20 degrees

Upper air data from numerical model forecast valid on 08/27/2015 at 0600 MDT

Freezing level.................. 15312 ft MSL (10005 ft AGL)
Convective condensation level... 13313 ft MSL (8006 ft AGL)
Lifted condensation level....... 13895 ft MSL (8589 ft AGL)
Lifted index.................... +0.2
K index......................... +28.4

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  -65.0 -85.0   290   27   14   2.6   1.5      M     M       M      M    M
 45000  -60.6 -77.1   290   44   23   3.6   2.0      M     M       M      M    M
 40000  -53.7 -64.7   275   36   18   8.9   4.9      M     M       M      M    M
 38000  -48.4 -55.1   270   29   15   8.9   4.9      M     M       M      M    M
 36000  -43.1 -45.6   265   23   12   9.0   4.9      M     M       M      M    M
 34000  -37.5 -35.5   270   25   13   9.3   5.1      M     M       M      M    M
 32000  -31.9 -25.4   270   27   14   9.3   5.1      M     M       M      M    M
 30000  -26.4 -15.5   270   25   13   8.0   4.4   50.0 121.9    16.0      M    M
 29000  -24.1 -11.4   270   24   12   8.0   4.4   49.4 120.8    15.7      M    M
 28000  -21.8  -7.2   265   23   12   6.6   3.6   48.7 119.6    15.3      M    M
 27000  -19.8  -3.6   265   24   12   6.8   3.7   47.4 117.3    14.4      M    M
 26000  -17.8  -0.0   260   25   13   6.8   3.7   46.3 115.3    13.7      M    M
 25000  -15.8   3.6   260   26   14   6.6   3.6   45.3 113.6    13.0      M    M
 24000  -14.1   6.6   260   27   14   6.0   3.3   43.9 111.0    11.9      M    M
 23000  -12.3   9.9   255   27   14   6.1   3.3   42.5 108.5    10.9      M    M
 22000  -10.6  12.9   255   27   14   5.9   3.2   41.3 106.3     9.9      M    M
 21000   -9.0  15.8   255   26   13   5.4   3.0   39.7 103.5     8.6      M    M
 20000   -7.4  18.7   260   26   13   5.5   3.0   38.2 100.7     7.3      M    M
 19500   -6.6  20.1   260   25   13   5.5   3.0   37.5  99.5     6.7      M    M
 19000   -5.9  21.4   265   25   13   5.2   2.9   36.7  98.1     6.1      M    M
 18500   -5.1  22.8   265   25   13   5.2   2.9   36.0  96.7     5.4      M    M
 18000   -4.4  24.1   270   25   13   5.3   2.9   35.2  95.3     4.7      M    M
 17500   -3.6  25.5   275   25   13   5.5   3.0   34.4  94.0     4.0      M    M
 17000   -2.8  27.0   275   25   13   5.5   3.0   33.7  92.7     3.4      M    M
 16500   -2.1  28.2   275   25   13   5.4   2.9   33.0  91.4     2.7      M    M
 16000   -1.3  29.7   275   25   13   5.4   3.0   32.3  90.1     2.0      M    M
 15500   -0.1  31.8   275   25   13   6.1   3.3   31.2  88.2     1.1      M    M
 15000    0.7  33.3   275   25   13   6.0   3.3   30.6  87.1     0.5      M    M
 14500    1.6  34.9   275   24   12   6.3   3.4   30.0  86.0    -0.1    776  3.9
 14000    2.5  36.5   275   23   12   6.3   3.5   29.4  85.0    -0.7    734  3.7
 13500    3.4  38.1   275   22   11   6.7   3.7   28.9  84.0    -1.2    692  3.5
 13000    4.5  40.1   280   20   10   7.1   3.9   28.4  83.2    -1.6    646  3.3
 12500    5.5  41.9   280   19   10   7.3   4.0   28.0  82.4    -2.1    600  3.0
 12000    6.6  43.9   280   17    9   7.7   4.2   27.7  81.8    -2.4    551  2.8
 11500    7.8  46.0   280   16    8   7.7   4.3   27.4  81.2    -2.7    502  2.6
 11000    9.0  48.2   280   15    8   7.7   4.2   27.1  80.7    -3.0    452  2.3
 10500   10.1  50.2   280   14    7   4.2   2.3   26.8  80.2    -3.3    402  2.0
 10250   10.3  50.5   280   14    7   5.8   3.2   26.2  79.2    -3.8    389  2.0
 10000   11.1  52.0   280   13    7  11.6   6.4   26.3  79.3    -3.8    358  1.8
  9750   11.9  53.4   280   12    6  10.4   5.7   26.3  79.4    -3.8    328  1.7
  9500   12.6  54.7   280   12    6   9.5   5.2   26.4  79.5    -3.7    297  1.5
  9250   13.2  55.8   285   12    6   7.0   3.9   26.3  79.3    -3.9    272  1.4
  9000   13.8  56.8   285   11    6   8.1   4.5   26.1  78.9    -4.1    249  1.3
  8750   14.4  57.9   285   11    6   9.4   5.2   26.0  78.8    -4.1    221  1.1
  8500   15.1  59.2   290   11    6   8.6   4.7   26.0  78.7    -4.2    194  1.0
  8250   15.7  60.3   290   11    6   7.9   4.3   25.8  78.5    -4.3    169  0.9
  8000   16.3  61.3   295   11    6   7.8   4.3   25.7  78.3    -4.5    144  0.7
  7750   16.8  62.2   295   11    6   7.8   4.3   25.6  78.0    -4.7    120  0.6
  7500   17.4  63.3   295   11    6   7.7   4.2   25.4  77.7    -4.9     96  0.5
  7250   18.0  64.4   295   11    5   7.5   4.1   25.2  77.4    -5.0     72  0.4
  7000   18.5  65.3   290   10    5   7.8   4.3   25.1  77.1    -5.2     48  0.2
  6750   19.1  66.4   290    9    5   7.9   4.3   24.9  76.9    -5.4     24  0.1
  6500   19.6  67.3   285    8    4   7.1   3.9   24.8  76.6    -5.6      1  0.0
  6250   20.0  68.0   280    7    4   6.6   3.6   24.5  76.2    -5.9      M    M
  6000   20.5  68.9   270    7    3   7.0   3.8   24.3  75.8    -6.2      M    M
  5750   21.0  69.8   255    7    4   5.0   2.7   24.1  75.3    -6.5      M    M
  5500   21.1  70.0   245    5    3   1.0   0.5   23.6  74.4    -7.1      M    M

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

           08/27/2015 at 0900 MDT          |       08/27/2015 at 1200 MDT
                                           |
K index... +25.8  LI... -0.1               | K index... +28.2  LI... -0.3
CAPE... 0.0  CIN... -0.4                   | CAPE... +4.8  CIN... -3.9
                                           |
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 -65.7 -86.3  280  29 15   2.9   1.6 | -65.0 -85.0  280  27 14   2.9   1.6
 45000 -60.5 -76.9  285  41 21   4.7   2.6 | -60.0 -76.0  280  40 20   4.5   2.4
 40000 -52.4 -62.3  275  32 16   7.6   4.2 | -52.2 -62.0  280  37 19   7.6   4.2
 38000 -47.8 -54.0  270  25 13   7.6   4.1 | -47.7 -53.9  280  34 17   7.6   4.2
 36000 -43.3 -45.9  265  18  9   8.0   4.4 | -43.2 -45.8  275  30 15   7.8   4.3
 34000 -38.0 -36.4  270  21 11   9.0   4.9 | -38.0 -36.4  275  26 13   8.6   4.7
 32000 -32.6 -26.7  275  24 12   8.9   4.9 | -32.8 -27.0  275  22 11   8.6   4.7
 30000 -27.5 -17.5  280  23 12   8.5   4.7 | -27.8 -18.0  285  22 11   8.5   4.7
 29000 -24.9 -12.8  280  22 11   8.6   4.7 | -24.6 -12.3  290  23 12   8.6   4.7
 28000 -21.9  -7.4  280  21 11   6.0   3.3 | -22.2  -8.0  295  23 12   6.4   3.5
 27000 -20.1  -4.2  280  20 10   6.3   3.4 | -20.3  -4.5  290  22 11   6.6   3.6
 26000 -18.3  -0.9  280  20 10   6.3   3.5 | -18.4  -1.1  290  21 11   6.7   3.7
 25000 -16.4   2.5  275  19 10   6.1   3.4 | -16.5   2.3  290  20 10   6.5   3.6
 24000 -14.8   5.4  275  18  9   5.8   3.2 | -14.7   5.5  285  20 10   5.9   3.3
 23000 -13.1   8.4  275  18  9   5.8   3.2 | -13.0   8.6  285  20 10   6.0   3.3
 22000 -11.4  11.5  275  17  9   5.9   3.2 | -11.3  11.7  280  20 10   6.1   3.3
 21000  -9.7  14.5  275  18  9   6.0   3.3 |  -9.4  15.1  285  20 11   6.4   3.5
 20000  -8.0  17.6  275  18  9   6.0   3.3 |  -7.6  18.3  290  21 11   6.4   3.5
 19500  -7.1  19.2  275  18  9   6.0   3.3 |  -6.6  20.1  290  21 11   6.4   3.5
 19000  -6.2  20.8  275  19 10   6.2   3.4 |  -5.7  21.7  295  21 11   6.7   3.7
 18500  -5.3  22.5  275  19 10   6.2   3.4 |  -4.7  23.5  295  21 11   6.6   3.6
 18000  -4.4  24.1  275  20 10   6.6   3.6 |  -3.8  25.2  300  22 11   6.4   3.5
 17500  -3.4  25.9  280  21 11   7.3   4.0 |  -2.9  26.8  300  22 11   5.9   3.2
 17000  -2.3  27.9  280  21 11   7.3   4.0 |  -2.1  28.2  300  22 11   6.0   3.3
 16500  -1.3  29.7  280  22 11   7.3   4.0 |  -1.3  29.7  300  22 11   4.9   2.7
 16000  -0.2  31.6  285  22 11   7.2   4.0 |  -0.6  30.9  300  22 11   4.9   2.7
 15500   0.8  33.4  285  23 12   6.2   3.4 |   0.4  32.7  305  22 11   5.0   2.7
 15000   1.9  35.4  285  22 11   5.1   2.8 |   1.1  34.0  305  22 11   5.0   2.7
 14500   2.6  36.7  290  21 11   4.1   2.3 |   1.8  35.2  305  21 11   4.9   2.7
 14000   3.1  37.6  290  19 10   3.9   2.1 |   2.5  36.5  305  21 11   4.9   2.7
 13500   3.6  38.5  290  18  9   4.6   2.5 |   3.2  37.8  305  20 10   5.6   3.1
 13000   4.4  39.9  290  16  8   5.4   2.9 |   4.1  39.4  305  19 10   6.2   3.4
 12500   5.2  41.4  290  14  7   5.7   3.1 |   5.0  41.0  305  17  9   6.4   3.5
 12000   6.1  43.0  295  12  6   6.3   3.4 |   6.0  42.8  310  16  8   6.7   3.7
 11500   7.0  44.6  300  10  5   6.6   3.6 |   7.0  44.6  310  15  8   7.0   3.9
 11000   8.0  46.4  305   9  5   7.4   4.1 |   8.1  46.6  310  14  7   7.7   4.2
 10500   9.2  48.6  315   9  4   4.2   2.3 |   9.2  48.6  315  12  6   3.5   1.9
 10250   9.4  48.9  320   9  4   5.5   3.0 |   9.4  48.9  315  12  6   5.6   3.1
 10000  10.1  50.2  325   9  5  11.0   6.0 |  10.2  50.4  320  12  6  12.7   7.0
  9750  10.8  51.4  330   9  5  10.4   5.7 |  11.0  51.8  325  11  6  11.3   6.2
  9500  11.6  52.9  340  10  5   9.1   5.0 |  11.8  53.2  325  11  6   9.9   5.4
  9250  12.1  53.8  340  10  5   6.6   3.6 |  12.4  54.3  330  11  5   7.3   4.0
  9000  12.6  54.7  340  11  6   8.6   4.7 |  13.0  55.4  330  10  5   9.7   5.3
  8750  13.4  56.1  340  12  6  10.5   5.8 |  13.8  56.8  330  10  5  11.4   6.3
  8500  14.1  57.4  340  13  7   9.3   5.1 |  14.6  58.3  335  10  5  10.5   5.8
  8250  14.8  58.6  340  14  7   8.5   4.6 |  15.3  59.5  335  10  5  10.1   5.5
  8000  15.4  59.7  335  14  7   8.5   4.6 |  16.1  61.0  335  10  5  10.0   5.5
  7750  16.0  60.8  330  15  8   8.6   4.7 |  16.8  62.2  335  10  5   9.9   5.4
  7500  16.6  61.9  330  15  8   7.4   4.0 |  17.6  63.7  335  10  5  10.1   5.6
  7250  17.1  62.8  325  15  8   6.5   3.5 |  18.3  64.9  335  10  5  10.4   5.7
  7000  17.5  63.5  320  14  7   6.5   3.5 |  19.1  66.4  335  10  5  10.2   5.6
  6750  18.0  64.4  315  13  6   7.2   4.0 |  19.9  67.8  335  10  5  10.3   5.6
  6500  18.6  65.5  315  11  6   9.5   5.2 |  20.7  69.3  335  10  5  10.8   5.9
  6250  19.3  66.7  315  10  5  10.8   5.9 |  21.5  70.7  335  10  5  11.8   6.5
  6000  20.1  68.2  310  10  5   8.9   4.9 |  22.3  72.1  335  10  5   9.0   4.9
  5750  20.8  69.4  310   9  5  11.4   6.3 |  23.0  73.4  340   9  5  14.0   7.7
  5500  22.0  71.6  310   9  4  20.6  11.3 |  24.7  76.5  340   9  5  30.6  16.8

           08/27/2015 at 1500 MDT          |       08/27/2015 at 1800 MDT
                                           |
K index... +29.1  LI... -1.5               | K index... +26.0  LI... -1.6
CAPE... +222.1  CIN... M                   | CAPE... +404.2  CIN... -16.3
                                           |
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 -64.7 -84.5  270  25 13   2.1   1.2 | -64.6 -84.3  260  26 13   2.6   1.4
 45000 -60.4 -76.7  270  38 19   4.4   2.4 | -59.8 -75.6  265  38 20   4.6   2.5
 40000 -52.7 -62.9  275  38 20   8.0   4.4 | -52.0 -61.6  270  43 22   7.0   3.8
 38000 -47.9 -54.2  275  36 18   8.0   4.4 | -47.8 -54.0  260  37 19   7.0   3.8
 36000 -43.1 -45.6  280  33 17   8.1   4.4 | -43.7 -46.7  250  33 17   7.2   3.9
 34000 -38.0 -36.4  280  31 16   8.4   4.6 | -38.7 -37.7  255  31 16   8.3   4.5
 32000 -33.0 -27.4  280  29 15   8.3   4.6 | -33.8 -28.8  260  29 15   8.2   4.5
 30000 -28.3 -18.9  285  26 13   7.9   4.3 | -29.0 -20.2  270  30 15   7.9   4.3
 29000 -25.3 -13.5  285  25 13   7.9   4.3 | -26.1 -15.0  270  31 16   7.9   4.3
 28000 -23.1  -9.6  290  24 12   6.9   3.8 | -23.7 -10.7  275  32 16   7.4   4.1
 27000 -21.0  -5.8  295  24 12   7.1   3.9 | -21.5  -6.7  275  33 17   7.5   4.1
 26000 -18.9  -2.0  300  24 12   7.1   3.9 | -19.3  -2.7  280  35 18   7.5   4.1
 25000 -16.8   1.8  305  24 12   7.0   3.8 | -17.1   1.2  280  37 19   7.3   4.0
 24000 -14.9   5.2  305  23 12   6.7   3.6 | -15.0   5.0  290  35 18   6.9   3.8
 23000 -13.0   8.6  305  22 11   6.7   3.7 | -12.9   8.8  295  33 17   6.9   3.8
 22000 -11.0  12.2  305  21 11   6.6   3.6 | -10.9  12.4  305  32 17   6.7   3.7
 21000  -9.2  15.4  305  21 11   6.3   3.5 |  -9.0  15.8  305  30 15   6.5   3.6
 20000  -7.4  18.7  305  21 11   6.4   3.5 |  -7.1  19.2  305  27 14   6.6   3.6
 19500  -6.5  20.3  305  21 11   6.5   3.5 |  -6.2  20.8  305  26 13   6.8   3.7
 19000  -5.6  21.9  305  21 11   5.6   3.1 |  -5.4  22.3  305  25 13   5.6   3.1
 18500  -4.8  23.4  305  21 11   5.7   3.1 |  -4.6  23.7  305  25 13   5.7   3.1
 18000  -3.9  25.0  310  22 11   5.4   3.0 |  -3.8  25.2  305  24 12   5.8   3.2
 17500  -3.2  26.2  310  23 12   4.9   2.7 |  -2.9  26.8  305  24 13   5.9   3.3
 17000  -2.5  27.5  310  23 12   4.9   2.7 |  -2.1  28.2  305  25 13   6.0   3.3
 16500  -1.7  28.9  310  24 12   5.6   3.0 |  -1.2  29.8  310  25 13   5.6   3.1
 16000  -0.9  30.4  310  24 12   5.5   3.0 |  -0.4  31.3  310  26 13   5.6   3.1
 15500   0.3  32.5  310  24 12   6.2   3.4 |   0.4  32.7  310  27 14   5.7   3.1
 15000   1.2  34.2  310  24 12   6.1   3.3 |   1.7  35.1  310  27 14   5.7   3.1
 14500   2.1  35.8  310  24 12   6.5   3.6 |   2.5  36.5  315  27 14   6.2   3.4
 14000   3.0  37.4  310  23 12   6.6   3.6 |   3.4  38.1  315  26 13   6.3   3.5
 13500   4.0  39.2  310  23 12   6.4   3.5 |   4.3  39.7  315  26 13   6.8   3.8
 13000   4.9  40.8  305  22 11   6.3   3.4 |   5.3  41.5  310  25 13   7.3   4.0
 12500   5.8  42.4  305  21 11   6.1   3.3 |   6.3  43.3  310  24 12   7.5   4.1
 12000   6.5  43.7  300  19 10   5.9   3.2 |   7.4  45.3  310  23 12   7.9   4.3
 11500   7.3  45.1  300  16  8   6.8   3.7 |   8.5  47.3  310  22 11   8.1   4.4
 11000   8.5  47.3  305  13  7   8.6   4.7 |   9.7  49.5  310  21 11   8.3   4.6
 10500   9.7  49.5  310  11  5   5.0   2.8 |  10.9  51.6  310  19 10   4.4   2.4
 10250  10.0  50.0  315  10  5   7.0   3.8 |  11.1  52.0  310  19 10   5.0   2.7
 10000  10.8  51.4  320  10  5  13.1   7.2 |  11.8  53.2  310  18  9  10.6   5.8
  9750  11.7  53.1  325  10  5  12.0   6.6 |  12.4  54.3  310  17  9   9.5   5.2
  9500  12.6  54.7  330  10  5  10.3   5.6 |  13.1  55.6  310  15  8   8.3   4.6
  9250  13.2  55.8  330  10  5   7.8   4.3 |  13.6  56.5  310  14  7   6.2   3.4
  9000  13.8  56.8  335  10  5  10.0   5.5 |  14.1  57.4  315  13  6   7.8   4.3
  8750  14.6  58.3  335  10  5  11.3   6.2 |  14.7  58.5  320  11  6   8.9   4.9
  8500  15.4  59.7  340  11  5  10.5   5.8 |  15.3  59.5  325   9  5   8.7   4.8
  8250  16.2  61.2  340  11  6  10.0   5.5 |  15.9  60.6  335   8  4   8.7   4.8
  8000  16.9  62.4  340  11  6  10.1   5.6 |  16.5  61.7  345   7  4   9.2   5.0
  7750  17.7  63.9  345  11  6  10.2   5.6 |  17.2  63.0  350   7  3   9.7   5.3
  7500  18.4  65.1  345  11  6  10.2   5.6 |  17.9  64.2  355   6  3   9.9   5.4
  7250  19.2  66.6  345  11  6  10.3   5.7 |  18.7  65.7  355   6  3  10.1   5.5
  7000  20.0  68.0  345  11  6  10.0   5.5 |  19.4  66.9  360   6  3  10.0   5.5
  6750  20.7  69.3  345  11  6   9.8   5.4 |  20.2  68.4  360   6  3  10.3   5.6
  6500  21.5  70.7  345  12  6  10.3   5.7 |  20.9  69.6  360   6  3  10.4   5.7
  6250  22.3  72.1  345  11  6  11.4   6.3 |  21.7  71.1  360   6  3  10.8   5.9
  6000  23.1  73.6  345  11  6   8.9   4.9 |  22.5  72.5  360   6  3   9.5   5.2
  5750  23.8  74.8  350  11  6  14.8   8.1 |  23.2  73.8  360   6  3  11.4   6.3
  5500  25.5  77.9  350  11  6  32.0  17.6 |  24.3  75.7  360   6  3  18.9  10.4
________________________________________________________________________________

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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