Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191256
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0656 MDT Friday, September 19, 2014

This forecast is for Friday, September 19, 2014:

If the trigger temperature of 84.7 F/29.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1163 ft/min (5.9 m/s)
   Maximum height of thermals.................. 17286 ft MSL (12001 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8035 ft MSL (2750 ft AGL)
Thermal soaring outlook for Saturday 09/20..... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 18063 ft MSL (12778 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 19291 ft MSL (14006 ft AGL)
Wave soaring outlook for Saturday 09/20........ Poor

Remarks... None

Sunrise/Sunset.................... 06:44:17 / 19:02:59 MDT
Total possible sunshine........... 12 hr 18 min 42 sec (738 min 42 sec)
Altitude of sun at 12:53:09 MDT... 51.53 degrees

Upper air data from rawinsonde observation taken on 09/19/2014 at 0600 MDT

Freezing level.................. 15679 ft MSL (10394 ft AGL)
Convective condensation level... 20596 ft MSL (15311 ft AGL)
Lifted condensation level....... 18717 ft MSL (13431 ft AGL)
Lifted index.................... +3.5
K index......................... +18.9

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  -67.3 -89.1   275   43   22  -0.2  -0.1   80.6 177.0    28.5      M    M
 45000  -60.7 -77.3   265   64   33   5.2   2.8   67.2 153.0    22.2      M    M
 40000  -52.4 -62.3   260   40   21   5.2   2.8   56.2 133.2    16.5      M    M
 38000  -50.1 -58.2   250   32   16   4.6   2.5   50.9 123.7    13.3      M    M
 36000  -46.5 -51.7   240   24   12   9.7   5.3   47.8 118.0    11.4      M    M
 34000  -41.0 -41.8   240   28   14   9.1   5.0   47.4 117.4    11.4      M    M
 32000  -35.5 -31.9   220   31   16   9.1   5.0   46.8 116.3    11.3      M    M
 30000  -31.1 -24.0   205   32   16   6.9   3.8   45.0 113.1    10.2      M    M
 29000  -28.9 -20.0   205   29   15   8.8   4.8   44.0 111.2     9.5      M    M
 28000  -25.7 -14.3   210   25   13   8.7   4.8   43.3 110.0     9.1      M    M
 27000  -23.1  -9.6   215   21   11   8.7   4.8   42.9 109.2     8.9      M    M
 26000  -20.5  -4.9   220   18    9   8.7   4.8   42.6 108.6     8.7      M    M
 25000  -17.9  -0.2   225   14    7   8.6   4.7   42.4 108.2     8.6      M    M
 24000  -15.5   4.1   230   13    6   8.0   4.4   41.7 107.0     8.2      M    M
 23000  -13.5   7.7   235   12    6   2.9   1.6   40.6 105.0     7.4      M    M
 22000  -12.6   9.3   240    9    5   8.5   4.7   38.1 100.7     5.4      M    M
 21000  -10.2  13.6   255    6    3   7.9   4.3   37.5  99.5     4.9      M    M
 20000   -8.3  17.1   225   12    6   4.8   2.6   36.4  97.4     4.0      M    M
 19500   -7.5  18.5   230   16    8   4.7   2.6   35.5  95.9     3.2      M    M
 19000   -6.7  19.9   235   19   10   6.7   3.7   34.8  94.6     2.6      M    M
 18500   -5.8  21.6   235   16    8   7.2   3.9   34.2  93.6     2.1      M    M
 18000   -5.1  22.8   235   13    7   2.7   1.5   33.4  92.2     1.3      M    M
 17500   -4.4  24.1   235   10    5   6.5   3.5   32.7  90.9     0.6      M    M
 17000   -3.9  25.0   235    7    3   6.8   3.7   31.8  89.3    -0.4   1151  5.8
 16500   -2.6  27.3   255    6    3   9.3   5.1   31.7  89.1    -0.6   1096  5.6
 16000   -1.2  29.8   275    8    4   9.4   5.2   31.7  89.1    -0.6   1040  5.3
 15500    0.2  32.4   290    9    4   9.4   5.2   31.7  89.0    -0.7    983  5.0
 15000    1.6  34.9   300   10    5   9.4   5.2   31.6  88.9    -0.7    926  4.7
 14500    3.0  37.4   300   11    6   9.4   5.2   31.5  88.8    -0.8    870  4.4
 14000    5.1  41.2   295   13    7   9.3   5.1   31.4  88.6    -0.9    785  4.0
 13500    6.5  43.7   300   12    6   9.1   5.0   31.3  88.4    -1.0    729  3.7
 13000    7.8  46.0   305   12    6   9.1   5.0   31.2  88.2    -1.1    674  3.4
 12500    9.1  48.4   310   11    6   9.1   5.0   31.1  88.0    -1.2    619  3.1
 12000   10.5  50.9   315   11    6   9.1   5.0   31.1  87.9    -1.3    564  2.9
 11500   11.8  53.2   325   12    6   9.1   5.0   30.9  87.7    -1.4    509  2.6
 11000   13.2  55.8   335   13    7   9.0   5.0   30.8  87.5    -1.5    454  2.3
 10500   14.5  58.1   330   13    7   9.0   4.9   30.7  87.3    -1.7    399  2.0
 10250   15.2  59.4   330   13    7   8.3   4.5   30.6  87.1    -1.8    372  1.9
 10000   15.8  60.4   330   12    6   7.8   4.3   30.5  86.8    -1.9    347  1.8
  9750   16.4  61.5   325   12    6   7.9   4.4   30.3  86.6    -2.1    322  1.6
  9500   16.9  62.4   325   11    6   7.9   4.3   30.2  86.3    -2.2    297  1.5
  9250   17.5  63.5   320   10    5   7.9   4.3   30.1  86.1    -2.3    272  1.4
  9000   18.1  64.6   320   10    5   7.9   4.3   29.9  85.9    -2.4    246  1.3
  8750   18.7  65.7   310    9    5   7.9   4.3   29.8  85.6    -2.6    221  1.1
  8500   19.3  66.7   300    8    4   7.9   4.3   29.6  85.3    -2.7    196  1.0
  8250   19.9  67.8   290    8    4   7.9   4.3   29.5  85.1    -2.9    171  0.9
  8000   20.5  68.9   280    8    4   8.1   4.4   29.4  84.8    -3.0    146  0.7
  7750   21.0  69.8   260    9    4   5.9   3.3   29.2  84.5    -3.2    122  0.6
  7500   21.4  70.5   245   10    5   4.2   2.3   28.8  83.8    -3.6    104  0.5
  7250   21.7  71.1   235   12    6   4.7   2.6   28.4  83.1    -4.0     87  0.4
  7000   22.1  71.8   225   14    7   4.6   2.5   28.0  82.4    -4.4     69  0.4
  6750   22.4  72.3   215   16    8   4.5   2.5   27.6  81.7    -4.8     51  0.3
  6500   22.8  73.0   210   18    9   4.8   2.6   27.2  80.9    -5.2     34  0.2
  6250   23.1  73.6   205   21   11   3.8   2.1   26.8  80.2    -5.6     16  0.1
  6000   23.4  74.1   200   24   12   7.3   4.0   26.4  79.6    -6.0      M    M
  5750   23.8  74.8   200   16    8  -5.6  -3.1   26.0  78.8    -6.4      M    M
  5500   22.1  71.8   210    8    4 -37.1 -20.3   23.6  74.6    -8.8     23  0.1

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

           09/19/2014 at 0900 MDT          |       09/19/2014 at 1200 MDT
                                           |
K index... +21.6  LI... +0.6               | K index... +22.1  LI... -0.9
CAPE... 0.0  CIN... -0.6                   | CAPE... +105.1  CIN... -88.4
                                           |
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 -66.3 -87.3  275  44 22   2.7   1.5 | -67.3 -89.1  270  47 24   3.4   1.9
 45000 -60.8 -77.4  270  60 31   6.1   3.3 | -60.8 -77.4  270  68 35   6.7   3.7
 40000 -51.9 -61.4  270  49 25   4.6   2.5 | -50.6 -59.1  270  57 29   4.9   2.7
 38000 -49.1 -56.4  260  38 20   4.6   2.5 | -47.7 -53.9  265  46 24   4.9   2.7
 36000 -46.3 -51.3  245  30 15   4.7   2.6 | -44.8 -48.6  255  35 18   4.7   2.6
 34000 -41.2 -42.2  235  27 14   8.3   4.6 | -40.9 -41.6  250  29 15   6.9   3.8
 32000 -36.2 -33.2  230  26 13   8.3   4.6 | -36.7 -34.1  245  23 12   6.9   3.8
 30000 -31.2 -24.2  230  23 12   8.2   4.5 | -32.0 -25.6  250  20 10   8.3   4.6
 29000 -28.7 -19.7  230  22 11   8.2   4.5 | -29.5 -21.1  250  18  9   8.3   4.6
 28000 -26.3 -15.3  230  20 10   8.0   4.4 | -27.0 -16.6  250  17  9   8.1   4.5
 27000 -23.9 -11.0  230  19 10   7.9   4.3 | -24.2 -11.6  250  16  8   7.5   4.1
 26000 -21.5  -6.7  230  17  9   7.9   4.3 | -21.9  -7.4  250  16  8   7.5   4.1
 25000 -19.1  -2.4  225  16  8   8.0   4.4 | -19.7  -3.5  250  15  8   7.4   4.0
 24000 -17.1   1.2  230  14  7   6.5   3.5 | -17.6   0.3  250  14  7   6.9   3.8
 23000 -15.2   4.6  235  12  6   6.5   3.6 | -15.6   3.9  250  12  6   6.9   3.8
 22000 -13.2   8.2  245  10  5   6.5   3.6 | -13.6   7.5  250  10  5   6.9   3.8
 21000 -11.3  11.7  250   8  4   6.4   3.5 | -11.6  11.1  255   9  5   6.6   3.6
 20000  -9.5  14.9  265   7  4   6.4   3.5 |  -9.7  14.5  265   7  4   6.6   3.6
 19500  -8.5  16.7  270   6  3   6.5   3.5 |  -8.8  16.2  270   6  3   6.6   3.6
 19000  -7.6  18.3  275   6  3   5.8   3.2 |  -7.8  18.0  275   6  3   6.9   3.8
 18500  -6.8  19.8  275   6  3   5.8   3.2 |  -6.8  19.8  270   6  3   6.9   3.8
 18000  -6.0  21.2  275   6  3   6.1   3.4 |  -5.8  21.6  270   6  3   7.1   3.9
 17500  -5.0  23.0  270   5  3   8.1   4.4 |  -4.7  23.5  260   5  3   7.6   4.2
 17000  -3.3  26.1  265   3  2   8.5   4.6 |  -3.6  25.5  245   5  3   7.6   4.2
 16500  -2.0  28.4  265   3  2   9.5   5.2 |  -2.4  27.7  240   5  3   9.2   5.0
 16000  -0.6  30.9  265   3  1   9.5   5.2 |  -1.1  30.0  235   5  3   9.2   5.0
 15500   0.8  33.4  270   3  1   9.1   5.0 |   0.2  32.4  235   5  2   9.1   5.0
 15000   2.1  35.8  280   2  1   9.1   5.0 |   1.6  34.9  240   4  2   9.1   5.0
 14500   3.5  38.3  295   2  1   9.2   5.0 |   2.9  37.2  245   3  2   9.0   5.0
 14000   4.9  40.8  310   2  1   9.2   5.0 |   4.8  40.6  270   2  1   8.6   4.7
 13500   6.2  43.2  325   3  1   9.2   5.0 |   6.1  43.0  315   1  1   8.6   4.7
 13000   7.6  45.7  335   3  2   9.1   5.0 |   7.3  45.1  350   2  1   8.7   4.8
 12500   9.0  48.2  345   4  2   9.0   4.9 |   8.6  47.5  010   3  2   8.6   4.7
 12000  10.3  50.5  345   5  3   8.8   4.8 |   9.9  49.8  015   5  3   8.6   4.7
 11500  11.6  52.9  345   6  3   8.8   4.8 |  11.1  52.0  020   6  3   8.5   4.7
 11000  12.9  55.2  345   7  4   8.4   4.6 |  12.3  54.1  015   8  4   8.1   4.4
 10500  14.1  57.4  345   8  4   5.3   2.9 |  13.5  56.3  005   9  5   5.1   2.8
 10250  14.4  57.9  345   8  4   6.0   3.3 |  13.8  56.8  005  10  5   6.2   3.4
 10000  15.1  59.2  345   9  5  10.6   5.8 |  14.5  58.1  005  10  5  10.9   6.0
  9750  15.8  60.4  345   9  5   9.6   5.2 |  15.2  59.4  005  11  6   9.8   5.4
  9500  16.5  61.7  340  10  5   9.2   5.0 |  16.0  60.8  360  11  6   9.3   5.1
  9250  17.1  62.8  340  10  5   7.2   3.9 |  16.6  61.9  360  11  6   7.9   4.4
  9000  17.6  63.7  340  11  5   7.7   4.2 |  17.2  63.0  360  12  6   8.3   4.6
  8750  18.3  64.9  340  11  6   8.9   4.9 |  17.8  64.0  360  12  6   8.7   4.8
  8500  18.9  66.0  335  11  6   8.2   4.5 |  18.4  65.1  360  12  6   8.2   4.5
  8250  19.4  66.9  335  11  6   7.0   3.8 |  19.0  66.2  360  11  6   7.7   4.2
  8000  19.9  67.8  335  11  6   6.6   3.6 |  19.6  67.3  005  11  6   7.0   3.9
  7750  20.4  68.7  330  11  6   7.0   3.8 |  20.1  68.2  005  11  6   6.2   3.4
  7500  21.0  69.8  330  11  6   6.4   3.5 |  20.5  68.9  010  10  5   7.1   3.9
  7250  21.4  70.5  325  11  6   5.9   3.2 |  21.1  70.0  015  10  5   7.7   4.2
  7000  21.8  71.2  325  11  6   5.2   2.9 |  21.6  70.9  020   9  4   7.9   4.3
  6750  22.1  71.8  320  11  6   5.2   2.9 |  22.2  72.0  025   7  4   8.8   4.8
  6500  22.4  72.3  320  11  6  -1.6  -0.9 |  22.8  73.0  030   6  3  10.2   5.6
  6250  21.9  71.4  315  10  5  -7.4  -4.0 |  23.6  74.5  030   6  3  11.5   6.3
  6000  21.5  70.7  305   9  5  -5.2  -2.9 |  24.5  76.1  030   6  3   9.8   5.4
  5750  21.1  70.0  295   8  4  -7.2  -3.9 |  25.2  77.4  030   6  3  12.0   6.6
  5500  20.3  68.5  270   6  3 -12.3  -6.7 |  26.4  79.5  030   6  3  21.7  11.9

           09/19/2014 at 1500 MDT          |       09/19/2014 at 1800 MDT
                                           |
K index... +21.2  LI... -1.8               | K index... +28.7  LI... -1.7
CAPE... +268.4  CIN... -43.2               | CAPE... +271.6  CIN... -41.6
                                           |
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 -67.0 -88.6  270  49 25   2.9   1.6 | -66.7 -88.1  275  49 25   2.8   1.5
 45000 -61.0 -77.8  270  71 37   6.9   3.8 | -61.1 -78.0  275  71 36   6.5   3.6
 40000 -50.5 -58.9  270  64 33   5.3   2.9 | -51.0 -59.8  275  67 34   5.7   3.1
 38000 -47.3 -53.1  270  54 28   5.3   2.9 | -47.6 -53.7  275  58 30   5.7   3.1
 36000 -44.1 -47.4  270  44 22   5.2   2.9 | -44.1 -47.4  270  48 25   5.6   3.1
 34000 -40.4 -40.7  265  37 19   6.4   3.5 | -40.3 -40.5  270  44 23   6.6   3.6
 32000 -36.5 -33.7  265  31 16   6.3   3.5 | -36.3 -33.3  275  41 21   6.6   3.6
 30000 -31.9 -25.4  265  24 12   8.1   4.4 | -31.7 -25.1  275  36 18   8.0   4.4
 29000 -29.5 -21.1  270  21 11   8.1   4.4 | -28.8 -19.8  275  33 17   8.0   4.4
 28000 -26.5 -15.7  275  17  9   7.5   4.1 | -26.4 -15.5  275  30 15   7.7   4.2
 27000 -24.3 -11.7  275  16  8   7.5   4.1 | -24.1 -11.4  275  26 13   7.7   4.2
 26000 -22.1  -7.8  280  14  7   7.5   4.1 | -21.8  -7.2  285  22 11   7.7   4.2
 25000 -19.8  -3.6  280  13  7   7.4   4.1 | -19.5  -3.1  290  18  9   7.6   4.2
 24000 -17.7   0.1  280  12  6   7.1   3.9 | -17.4   0.7  290  16  8   7.0   3.8
 23000 -15.6   3.9  275  12  6   7.1   3.9 | -15.3   4.5  290  14  7   7.0   3.8
 22000 -13.5   7.7  270  11  6   7.0   3.8 | -13.3   8.1  290  13  7   6.9   3.8
 21000 -11.6  11.1  275  11  5   6.6   3.6 | -11.3  11.7  290  13  7   6.6   3.6
 20000  -9.7  14.5  275  10  5   6.6   3.6 |  -9.4  15.1  290  14  7   6.6   3.6
 19500  -8.8  16.2  280  10  5   6.5   3.6 |  -8.5  16.7  290  15  8   6.6   3.6
 19000  -7.7  18.1  280   9  5   8.1   4.5 |  -7.5  18.5  290  15  8   7.5   4.1
 18500  -6.5  20.3  285   9  5   8.1   4.4 |  -6.4  20.5  290  15  8   7.5   4.1
 18000  -5.3  22.5  290   9  5   8.0   4.4 |  -5.3  22.5  290  15  8   7.6   4.2
 17500  -4.2  24.4  285   9  4   7.9   4.3 |  -4.2  24.4  295  14  7   8.0   4.4
 17000  -3.0  26.6  285   8  4   7.9   4.4 |  -3.1  26.4  300  13  7   8.0   4.4
 16500  -1.9  28.6  280   8  4   8.0   4.4 |  -2.0  28.4  305  12  6   8.5   4.6
 16000  -0.7  30.7  270   7  4   8.0   4.4 |  -0.8  30.6  305  11  5   8.5   4.7
 15500   0.5  32.9  265   7  4   8.3   4.6 |   0.4  32.7  310   9  5   8.4   4.6
 15000   1.8  35.2  260   7  4   8.5   4.7 |   1.6  34.9  315   8  4   8.3   4.5
 14500   3.0  37.4  260   7  4   8.6   4.7 |   3.5  38.3  320   7  3   8.4   4.6
 14000   5.0  41.0  265   6  3   8.9   4.9 |   4.8  40.6  320   5  3   8.5   4.7
 13500   6.2  43.2  270   5  3   8.7   4.8 |   6.0  42.8  320   4  2   8.3   4.6
 13000   7.5  45.5  275   4  2   8.5   4.6 |   7.3  45.1  320   4  2   8.2   4.5
 12500   8.7  47.7  285   3  2   8.5   4.7 |   8.5  47.3  320   3  1   8.3   4.6
 12000  10.0  50.0  295   3  1   8.6   4.7 |   9.8  49.6  335   2  1   8.8   4.8
 11500  11.2  52.2  305   3  1   8.5   4.7 |  11.1  52.0  355   1  1   8.7   4.8
 11000  12.4  54.3  335   3  2   8.1   4.5 |  12.4  54.3  025   2  1   8.5   4.7
 10500  13.6  56.5  350   4  2   5.4   3.0 |  13.6  56.5  045   2  1   6.0   3.3
 10250  13.9  57.0  355   5  2   6.4   3.5 |  13.9  57.0  045   3  1   7.2   3.9
 10000  14.6  58.3  005   5  2  10.8   5.9 |  14.7  58.5  045   3  1  11.3   6.2
  9750  15.3  59.5  015   5  2   9.9   5.4 |  15.4  59.7  045   3  1  10.5   5.8
  9500  16.0  60.8  025   5  3   9.3   5.1 |  16.2  61.2  040   3  1   9.7   5.3
  9250  16.7  62.1  030   5  3   8.4   4.6 |  16.8  62.2  040   3  1   8.5   4.7
  9000  17.3  63.1  030   5  3   9.5   5.2 |  17.5  63.5  040   3  1   9.6   5.3
  8750  18.0  64.4  030   5  3   9.8   5.4 |  18.2  64.8  035   3  1  10.1   5.5
  8500  18.7  65.7  030   5  3  10.1   5.5 |  19.0  66.2  035   3  1  10.1   5.5
  8250  19.5  67.1  030   5  3  10.9   6.0 |  19.7  67.5  030   2  1  10.5   5.7
  8000  20.3  68.5  030   5  3  10.2   5.6 |  20.5  68.9  025   2  1   9.9   5.4
  7750  21.0  69.8  030   5  3   9.3   5.1 |  21.2  70.2  020   2  1   9.3   5.1
  7500  21.7  71.1  030   5  3   9.8   5.4 |  21.9  71.4  020   2  1   9.6   5.3
  7250  22.4  72.3  030   5  3  10.1   5.5 |  22.6  72.7  015   2  1   9.9   5.4
  7000  23.2  73.8  030   5  3   9.9   5.4 |  23.4  74.1  010   2  1   9.6   5.3
  6750  23.9  75.0  030   5  3   9.6   5.3 |  24.1  75.4  005   2  1   9.0   4.9
  6500  24.6  76.3  030   5  3  10.2   5.6 |  24.7  76.5  005   2  1   9.4   5.2
  6250  25.4  77.7  030   5  2  11.1   6.1 |  25.5  77.9  360   2  1   9.9   5.4
  6000  26.2  79.2  030   5  2  10.0   5.5 |  26.2  79.2  355   2  1   9.7   5.3
  5750  27.0  80.6  030   5  2  12.4   6.8 |  26.9  80.4  355   2  1  10.1   5.6
  5500  28.2  82.8  030   5  2  20.9  11.5 |  27.6  81.7  355   2  1  11.2   6.1
________________________________________________________________________________

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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