Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290145
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1945 MDT Thursday, August 28, 2014

This forecast is for Friday, August 29, 2014:

If the trigger temperature of 74.3 F/23.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 850 ft/min (4.3 m/s)
   Maximum height of thermals.................. 15203 ft MSL (9916 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1015 MDT
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................. 12829 ft MSL (7541 ft AGL)
Thermal soaring outlook for Saturday 08/30..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14371 ft MSL (9084 ft AGL)
Wave soaring outlook for Saturday 08/30........ Fair

Remarks... Flat upper level ridge over colorado with moderate northwesterly flow
           aloft.

Sunrise/Sunset.................... 06:24:42 / 19:36:40 MDT
Total possible sunshine........... 13 hr 11 min 58 sec (791 min 58 sec)
Altitude of sun at 13:00:16 MDT... 59.41 degrees

Upper air data from numerical model forecast valid on 08/29/2014 at 0600 MDT

Freezing level.................. 14280 ft MSL (8993 ft AGL)
Convective condensation level... 15364 ft MSL (10077 ft AGL)
Lifted condensation level....... 15381 ft MSL (10093 ft AGL)
Lifted index.................... -0.6
K index......................... +3.0

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  -62.5 -80.5   290   23   12   1.3   0.7      M     M       M      M    M
 45000  -59.3 -74.7   300   28   15   4.7   2.6      M     M       M      M    M
 40000  -52.0 -61.6   300   33   17   4.4   2.4      M     M       M      M    M
 38000  -49.4 -56.9   295   34   17   4.4   2.4      M     M       M      M    M
 36000  -46.7 -52.1   290   34   18   4.5   2.4      M     M       M      M    M
 34000  -42.9 -45.2   285   33   17   7.0   3.9      M     M       M      M    M
 32000  -38.7 -37.7   285   31   16   7.1   3.9      M     M       M      M    M
 30000  -34.0 -29.2   285   28   15   8.4   4.6   42.1 107.8    10.5      M    M
 29000  -31.4 -24.5   285   27   14   8.4   4.6   41.6 106.8    10.2      M    M
 28000  -28.9 -20.0   285   26   13   8.5   4.6   41.2 106.1    10.0      M    M
 27000  -25.9 -14.6   290   24   12   7.9   4.3   40.3 104.5     9.4      M    M
 26000  -23.6 -10.5   295   23   12   7.9   4.3   39.6 103.2     8.9      M    M
 25000  -21.2  -6.2   295   22   11   8.0   4.4   39.0 102.1     8.6      M    M
 24000  -18.9  -2.0   300   21   11   7.6   4.2   38.2 100.7     8.0      M    M
 23000  -16.6   2.1   305   21   11   7.6   4.2   37.4  99.2     7.4      M    M
 22000  -14.4   6.1   305   20   10   7.6   4.2   36.7  98.0     6.9      M    M
 21000  -12.5   9.5   310   18    9   5.9   3.3   35.4  95.7     5.9      M    M
 20000  -10.8  12.6   315   16    8   6.0   3.3   34.0  93.3     4.8      M    M
 19500   -9.9  14.2   320   15    8   6.0   3.3   33.4  92.2     4.3      M    M
 19000   -9.0  15.8   325   14    7   5.9   3.2   32.8  91.1     3.7      M    M
 18500   -8.1  17.4   330   13    7   5.8   3.2   32.1  89.8     3.2      M    M
 18000   -7.2  19.0   335   13    7   6.0   3.3   31.4  88.6     2.6      M    M
 17500   -6.2  20.8   340   13    7   7.3   4.0   30.9  87.7     2.2      M    M
 17000   -5.1  22.8   340   13    7   7.3   4.0   30.5  86.9     1.8      M    M
 16500   -4.1  24.6   345   13    7   6.8   3.7   30.1  86.1     1.4      M    M
 16000   -3.1  26.4   350   14    7   6.6   3.6   29.5  85.2     1.0      M    M
 15500   -2.1  28.2   355   15    8   6.1   3.4   29.0  84.3     0.5      M    M
 15000   -1.3  29.7   355   16    8   5.4   2.9   28.3  82.9    -0.1    843  4.3
 14500   -0.5  31.1   355   18    9   5.4   3.0   27.6  81.7    -0.8    805  4.1
 14000    0.6  33.1   355   20   10   5.6   3.1   26.5  79.7    -1.9    749  3.8
 13500    1.4  34.5   350   21   11   6.9   3.8   25.8  78.5    -2.6    712  3.6
 13000    2.5  36.5   350   22   11   8.3   4.6   25.6  78.1    -3.0    662  3.4
 12500    3.7  38.7   350   24   12   8.4   4.6   25.4  77.7    -3.3    613  3.1
 12000    4.8  40.6   350   25   13   8.5   4.6   25.1  77.3    -3.7    565  2.9
 11500    5.9  42.6   350   25   13   8.9   4.9   25.0  76.9    -4.0    518  2.6
 11000    7.2  45.0   345   24   12   9.2   5.1   24.9  76.8    -4.2    463  2.4
 10500    8.6  47.5   345   22   12   5.1   2.8   24.9  76.8    -4.2    406  2.1
 10250    8.8  47.8   345   22   11   5.6   3.1   24.3  75.8    -4.8    392  2.0
 10000    9.6  49.3   345   21   11  12.0   6.6   24.4  75.9    -4.7    361  1.8
  9750   10.4  50.7   345   20   10  11.3   6.2   24.5  76.1    -4.6    329  1.7
  9500   11.3  52.3   340   19   10   9.9   5.4   24.6  76.3    -4.5    297  1.5
  9250   11.9  53.4   340   18    9   7.1   3.9   24.5  76.1    -4.7    271  1.4
  9000   12.4  54.3   340   17    9   8.3   4.6   24.3  75.7    -4.9    247  1.3
  8750   13.1  55.6   340   16    8   9.6   5.3   24.3  75.7    -4.9    219  1.1
  8500   13.8  56.8   340   15    8   8.7   4.8   24.2  75.6    -5.0    192  1.0
  8250   14.4  57.9   335   14    7   8.0   4.4   24.1  75.4    -5.1    166  0.8
  8000   15.0  59.0   335   13    6   8.1   4.5   24.0  75.2    -5.2    140  0.7
  7750   15.6  60.1   330   12    6   8.2   4.5   23.9  74.9    -5.4    115  0.6
  7500   16.2  61.2   330   11    6   8.7   4.8   23.7  74.7    -5.5     89  0.5
  7250   16.8  62.2   325   12    6   8.6   4.7   23.7  74.6    -5.6     63  0.3
  7000   17.5  63.5   325   12    6   9.8   5.4   23.6  74.5    -5.7     36  0.2
  6750   18.2  64.8   320   13    7   6.5   3.6   23.6  74.4    -5.8      9  0.0
  6500   18.3  64.9   315   14    7  -1.0  -0.5   23.0  73.4    -6.4      M    M
  6250   17.9  64.2   305   14    7  -8.0  -4.4   22.0  71.5    -7.5      0  0.0
  6000   17.6  63.7   300   14    7   8.4   4.6   20.9  69.7    -8.6      4  0.0
  5750   18.4  65.1   295   17    9  -7.0  -3.9   21.0  69.8    -8.5      M    M
  5500   15.0  59.0   275   10    5 -77.2 -42.4   17.1  62.7   -12.6     66  0.3

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

           08/29/2014 at 0900 MDT          |       08/29/2014 at 1200 MDT
                                           |
K index... +14.2  LI... -1.0               | K index... +21.5  LI... -3.0
CAPE... +196.0  CIN... -23.5               | CAPE... +529.2  CIN... -8.3
                                           |
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 -62.3 -80.1  290  24 13   1.4   0.8 | -62.1 -79.8  280  24 13   2.0   1.1
 45000 -59.0 -74.2  295  31 16   4.7   2.6 | -58.2 -72.8  285  33 17   4.4   2.4
 40000 -51.8 -61.2  290  33 17   5.0   2.7 | -51.4 -60.5  285  35 18   3.8   2.1
 38000 -48.8 -55.8  290  32 16   5.0   2.7 | -49.1 -56.4  290  35 18   3.8   2.1
 36000 -45.9 -50.6  290  30 16   5.0   2.7 | -46.8 -52.2  295  35 18   3.9   2.1
 34000 -42.0 -43.6  290  28 15   6.0   3.3 | -43.0 -45.4  295  34 17   7.4   4.1
 32000 -38.3 -36.9  290  26 14   6.1   3.3 | -38.5 -37.3  300  32 17   7.4   4.1
 30000 -34.4 -29.9  290  25 13   6.7   3.7 | -34.4 -29.9  300  29 15   6.7   3.7
 29000 -32.4 -26.3  290  24 12   6.7   3.7 | -32.4 -26.3  300  27 14   6.7   3.7
 28000 -30.4 -22.7  290  24 12   7.1   3.9 | -29.8 -21.6  295  25 13   7.3   4.0
 27000 -27.9 -18.2  295  23 12   8.8   4.8 | -27.5 -17.5  295  23 12   8.1   4.4
 26000 -25.2 -13.4  295  23 12   8.7   4.8 | -25.0 -13.0  295  21 11   8.1   4.4
 25000 -22.6  -8.7  300  22 12   8.8   4.8 | -22.6  -8.7  295  20 10   8.2   4.5
 24000 -20.2  -4.4  300  22 11   7.8   4.3 | -20.4  -4.7  300  19 10   7.5   4.1
 23000 -17.8  -0.0  300  20 11   7.8   4.3 | -18.1  -0.6  300  18  9   7.5   4.1
 22000 -15.5   4.1  300  19 10   8.0   4.4 | -15.9   3.4  305  18  9   7.5   4.1
 21000 -13.5   7.7  300  19 10   6.3   3.5 | -13.9   7.0  310  17  9   6.3   3.5
 20000 -11.6  11.1  300  18  9   6.4   3.5 | -12.1  10.2  315  16  8   6.3   3.5
 19500 -10.6  12.9  300  18  9   6.4   3.5 | -11.1  12.0  315  16  8   6.3   3.4
 19000  -9.7  14.5  300  17  9   7.4   4.1 | -10.2  13.6  315  16  8   7.5   4.1
 18500  -8.4  16.9  295  16  8   8.0   4.4 |  -9.0  15.8  315  15  8   7.7   4.2
 18000  -7.2  19.0  295  14  7   8.0   4.4 |  -7.9  17.8  315  15  8   7.7   4.2
 17500  -6.2  20.8  295  14  7   5.4   3.0 |  -6.7  19.9  315  15  8   7.6   4.2
 17000  -5.0  23.0  305  13  7   5.7   3.1 |  -5.6  21.9  315  15  8   7.8   4.3
 16500  -4.1  24.6  310  13  7   5.7   3.1 |  -4.6  23.7  320  15  8   4.9   2.7
 16000  -3.3  26.1  320  13  6   5.7   3.1 |  -4.0  24.8  325  15  8   4.7   2.6
 15500  -2.5  27.5  330  13  7   5.6   3.1 |  -3.4  25.9  325  16  8   5.8   3.2
 15000  -1.7  28.9  335  13  7   5.7   3.1 |  -2.3  27.9  330  15  8   7.1   3.9
 14500  -0.9  30.4  345  14  7   6.9   3.8 |  -0.8  30.6  340  14  7   8.5   4.6
 14000   0.2  32.4  350  15  8   7.6   4.2 |   0.5  32.9  340  14  7   8.8   4.8
 13500   1.3  34.3  355  16  8   7.9   4.3 |   1.8  35.2  345  14  7   8.8   4.8
 13000   2.4  36.3  355  17  9   8.2   4.5 |   3.0  37.4  345  14  7   8.7   4.8
 12500   3.5  38.3  355  18  9   8.5   4.7 |   4.3  39.7  350  13  7   8.8   4.8
 12000   4.7  40.5  355  18  9   8.9   4.9 |   5.5  41.9  350  12  6   8.9   4.9
 11500   6.0  42.8  355  18  9   9.0   4.9 |   6.7  44.1  350  11  6   8.9   4.9
 11000   7.3  45.1  350  18  9   9.2   5.0 |   8.0  46.4  345  11  6   8.5   4.7
 10500   8.7  47.7  350  17  9   5.6   3.1 |   9.2  48.6  345  10  5   4.1   2.3
 10250   8.9  48.0  350  17  9   5.9   3.2 |   9.4  48.9  340  10  5   5.7   3.1
 10000   9.7  49.5  350  17  9  12.1   6.6 |  10.2  50.4  340  10  5  12.7   7.0
  9750  10.5  50.9  345  17  9  12.1   6.6 |  11.0  51.8  340  10  5  11.4   6.3
  9500  11.4  52.5  345  17  8  10.4   5.7 |  11.8  53.2  340  10  5   9.5   5.2
  9250  12.0  53.6  345  16  8   7.4   4.1 |  12.4  54.3  340   9  5   6.8   3.8
  9000  12.6  54.7  345  15  8   8.7   4.8 |  12.9  55.2  340   8  4   9.1   5.0
  8750  13.3  55.9  345  14  7  10.4   5.7 |  13.6  56.5  335   7  4  10.3   5.6
  8500  14.0  57.2  345  13  7   8.9   4.9 |  14.3  57.7  335   6  3   9.9   5.4
  8250  14.6  58.3  340  12  6   7.6   4.2 |  15.1  59.2  335   5  3   9.8   5.4
  8000  15.2  59.4  340  11  6   8.0   4.4 |  15.8  60.4  335   4  2  10.0   5.5
  7750  15.8  60.4  335  10  5   8.4   4.6 |  16.5  61.7  335   4  2  10.1   5.6
  7500  16.4  61.5  330  10  5   8.6   4.7 |  17.2  63.0  330   4  2  10.0   5.5
  7250  17.1  62.8  325  11  5   8.6   4.7 |  18.0  64.4  330   4  2   9.9   5.4
  7000  17.7  63.9  325  11  6   9.0   4.9 |  18.7  65.7  330   4  2  10.0   5.5
  6750  18.3  64.9  320  12  6   6.8   3.7 |  19.5  67.1  330   4  2  10.5   5.7
  6500  18.6  65.5  315  12  6   1.5   0.8 |  20.3  68.5  330   4  2  10.7   5.8
  6250  18.6  65.5  310  11  6   1.7   0.9 |  21.1  70.0  330   4  2  11.3   6.2
  6000  18.7  65.7  300  11  6  -4.0  -2.2 |  21.9  71.4  330   3  2   9.0   5.0
  5750  18.2  64.8  285  12  6  -2.9  -1.6 |  22.6  72.7  330   3  2  13.3   7.3
  5500  18.6  65.5  275   8  4  17.1   9.4 |  24.1  75.4  330   3  2  26.9  14.7

           08/29/2014 at 1500 MDT          |       08/29/2014 at 1800 MDT
                                           |
K index... +26.9  LI... -2.8               | K index... +26.3  LI... -2.0
CAPE... +476.4  CIN... -15.2               | CAPE... +275.3  CIN... -40.0
                                           |
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 -62.2 -80.0  270  29 15   2.3   1.2 | -61.8 -79.2  265  27 14   2.8   1.5
 45000 -58.3 -72.9  275  37 19   3.7   2.0 | -57.9 -72.2  275  30 15   2.1   1.1
 40000 -52.4 -62.3  285  40 20   4.6   2.5 | -54.3 -65.7  285  36 18   5.6   3.1
 38000 -49.7 -57.5  290  37 19   4.5   2.5 | -51.2 -60.2  290  30 15   5.3   2.9
 36000 -47.0 -52.6  295  35 18   4.6   2.5 | -48.0 -54.4  295  24 13   5.4   3.0
 34000 -43.3 -45.9  295  34 18   6.9   3.8 | -43.9 -47.0  300  22 11   7.3   4.0
 32000 -39.2 -38.6  290  33 17   6.9   3.8 | -39.6 -39.3  305  20 10   7.3   4.0
 30000 -34.7 -30.5  290  31 16   7.8   4.3 | -34.7 -30.5  305  20 10   8.5   4.7
 29000 -32.4 -26.3  295  29 15   7.8   4.3 | -32.2 -26.0  310  20 10   8.5   4.7
 28000 -29.5 -21.1  300  26 14   7.8   4.3 | -29.0 -20.2  310  20 10   8.1   4.4
 27000 -27.2 -17.0  300  24 13   7.8   4.3 | -26.8 -16.2  310  20 10   7.6   4.2
 26000 -24.9 -12.8  300  23 12   7.8   4.3 | -24.5 -12.1  310  20 10   7.7   4.2
 25000 -22.6  -8.7  300  21 11   7.9   4.3 | -22.3  -8.1  310  20 10   7.7   4.2
 24000 -20.4  -4.7  300  20 10   7.2   3.9 | -20.1  -4.2  310  19 10   7.2   4.0
 23000 -18.2  -0.8  305  19 10   7.2   3.9 | -18.0  -0.4  310  19 10   7.2   4.0
 22000 -16.1   3.0  305  18  9   7.2   3.9 | -15.8   3.6  310  19 10   7.2   4.0
 21000 -14.1   6.6  310  17  9   6.7   3.7 | -13.9   7.0  310  18  9   6.5   3.6
 20000 -12.2  10.0  315  16  8   6.7   3.7 | -12.0  10.4  310  18  9   6.5   3.6
 19500 -11.2  11.8  315  16  8   6.7   3.6 | -11.0  12.2  310  17  9   6.5   3.6
 19000 -10.2  13.6  320  15  8   7.1   3.9 | -10.0  14.0  310  17  9   6.7   3.7
 18500  -9.1  15.6  320  14  7   7.2   4.0 |  -9.1  15.6  310  17  9   6.7   3.7
 18000  -8.1  17.4  320  13  7   7.3   4.0 |  -8.1  17.4  305  17  9   6.8   3.7
 17500  -7.0  19.4  320  13  7   7.7   4.2 |  -7.1  19.2  305  17  9   7.3   4.0
 17000  -5.9  21.4  320  13  7   7.7   4.2 |  -6.0  21.2  305  17  9   7.3   4.0
 16500  -4.8  23.4  320  13  7   7.4   4.0 |  -5.0  23.0  305  17  9   7.6   4.2
 16000  -3.7  25.3  325  13  7   7.4   4.1 |  -3.9  25.0  305  17  9   7.7   4.2
 15500  -2.7  27.1  325  13  7   7.6   4.2 |  -2.8  27.0  305  17  9   7.7   4.2
 15000  -1.5  29.3  330  13  7   7.8   4.3 |  -1.6  29.1  305  16  8   7.7   4.2
 14500  -0.4  31.3  335  13  7   7.8   4.3 |  -0.5  31.1  310  15  8   7.8   4.3
 14000   1.3  34.3  335  13  7   7.9   4.3 |   1.4  34.5  310  14  7   8.7   4.8
 13500   2.4  36.3  335  12  6   8.2   4.5 |   2.7  36.9  310  13  7   8.5   4.7
 13000   3.7  38.7  335  11  6   8.6   4.7 |   3.9  39.0  315  12  6   8.4   4.6
 12500   4.9  40.8  335  10  5   8.6   4.7 |   5.2  41.4  320  11  5   8.4   4.6
 12000   6.2  43.2  335   9  4   8.5   4.7 |   6.4  43.5  320  10  5   8.5   4.7
 11500   7.4  45.3  330   7  4   8.5   4.6 |   7.7  45.9  320   9  4   8.5   4.6
 11000   8.6  47.5  325   6  3   8.1   4.5 |   8.9  48.0  320   8  4   8.1   4.5
 10500   9.7  49.5  320   5  2   4.4   2.4 |  10.2  50.4  320   7  4   4.1   2.3
 10250  10.0  50.0  315   4  2   6.5   3.5 |  10.3  50.5  320   7  4   5.1   2.8
 10000  10.8  51.4  315   4  2  12.9   7.1 |  11.1  52.0  325   7  4  11.3   6.2
  9750  11.6  52.9  310   4  2  11.6   6.4 |  11.8  53.2  325   6  3   9.9   5.4
  9500  12.5  54.5  310   4  2  10.3   5.7 |  12.5  54.5  330   6  3   9.4   5.1
  9250  13.1  55.6  310   4  2   8.4   4.6 |  13.1  55.6  330   6  3   8.3   4.5
  9000  13.8  56.8  310   4  2  10.0   5.5 |  13.7  56.7  335   6  3   9.2   5.1
  8750  14.6  58.3  310   4  2  10.8   5.9 |  14.4  57.9  335   5  3   9.8   5.4
  8500  15.4  59.7  305   4  2  10.4   5.7 |  15.1  59.2  340   5  3   9.5   5.2
  8250  16.1  61.0  305   4  2  10.4   5.7 |  15.8  60.4  340   5  3   9.3   5.1
  8000  16.9  62.4  305   5  2  10.0   5.5 |  16.4  61.5  345   5  3   9.2   5.0
  7750  17.6  63.7  305   5  2   9.5   5.2 |  17.1  62.8  345   5  3   9.0   5.0
  7500  18.3  64.9  305   5  2  10.1   5.6 |  17.8  64.0  345   5  3   9.8   5.4
  7250  19.1  66.4  305   5  2  10.7   5.8 |  18.5  65.3  340   5  3  10.4   5.7
  7000  19.9  67.8  305   5  2  10.2   5.6 |  19.2  66.6  340   6  3   9.9   5.4
  6750  20.6  69.1  300   5  2   9.8   5.4 |  20.0  68.0  340   6  3   9.5   5.2
  6500  21.4  70.5  300   5  2  10.1   5.5 |  20.7  69.3  335   6  3   9.9   5.4
  6250  22.2  72.0  300   5  2  11.0   6.0 |  21.4  70.5  335   6  3  10.2   5.6
  6000  22.9  73.2  300   5  2   8.8   4.8 |  22.2  72.0  335   6  3  10.0   5.5
  5750  23.6  74.5  300   5  2  13.6   7.4 |  22.9  73.2  335   6  3  11.0   6.0
  5500  25.1  77.2  300   5  2  27.7  15.2 |  23.8  74.8  335   5  3  12.9   7.1
________________________________________________________________________________

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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