Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 071305
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0704 MDT Monday, July 7, 2014

This forecast is for Monday, July 7, 2014:

If the trigger temperature of 89.6 F/32.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1521 ft/min (7.7 m/s)
   Maximum height of thermals.................. 20655 ft MSL (15370 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11753 ft MSL (6468 ft AGL)
Thermal soaring outlook for Tuesday 07/08...... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14401 ft MSL (9116 ft AGL)
Wave soaring outlook for Tuesday 07/08......... Poor

Remarks... Strong cold front will settle in against the front range this
           evening. Moist upslope flow there after through Tuesday.

Sunrise/Sunset.................... 05:38:37 / 20:30:17 MDT
Total possible sunshine........... 14 hr 51 min 40 sec (891 min 40 sec)
Altitude of sun at 13:04:26 MDT... 72.73 degrees

Upper air data from rawinsonde observation taken on 07/07/2014 at 0600 MDT

Freezing level.................. 16573 ft MSL (11288 ft AGL)
Convective condensation level... 18129 ft MSL (12844 ft AGL)
Lifted condensation level....... 19089 ft MSL (13803 ft AGL)
Lifted index.................... -2.2
K index......................... +18.8

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  -65.9 -86.6   015   25   13  -3.1  -1.7   82.2 180.0    26.9      M    M
 45000  -63.8 -82.8   335   24   12   5.9   3.2   61.1 142.0    15.7      M    M
 40000  -53.5 -64.3   325   27   14   5.8   3.2   54.5 130.1    12.3      M    M
 38000  -49.3 -56.7   315   30   15   9.1   5.0   52.2 125.9    11.1      M    M
 36000  -44.5 -48.1   310   29   15   7.3   4.0   50.6 123.2    10.3      M    M
 34000  -39.8 -39.6   305   26   13   6.6   3.6   49.1 120.4     9.4      M    M
 32000  -35.3 -31.5   295   22   11   5.8   3.2   46.3 115.3     7.6      M    M
 30000  -30.5 -22.9   290   17    9   8.7   4.8   44.8 112.7     6.7      M    M
 29000  -27.9 -18.2   290   15    8   8.7   4.8   44.3 111.8     6.4      M    M
 28000  -25.3 -13.5   295   13    7   7.7   4.2   44.0 111.1     6.1      M    M
 27000  -23.6 -10.5   295   11    6   5.0   2.7   42.4 108.3     4.9      M    M
 26000  -22.0  -7.6   300   10    5   8.3   4.6   40.9 105.5     3.7      M    M
 25000  -19.5  -3.1   305    8    4   8.5   4.7   40.4 104.6     3.3      M    M
 24000  -16.9   1.6   300    9    5   8.7   4.8   39.9 103.8     2.9      M    M
 23000  -14.3   6.3   290   10    5   8.9   4.9   39.5 103.2     2.7      M    M
 22000  -12.3   9.9   285   11    6   6.2   3.4   38.6 101.4     1.8      M    M
 21000  -10.4  13.3   285   13    6   8.7   4.8   37.4  99.3     0.8      M    M
 20000   -8.8  16.2   280   14    7   8.9   4.9   35.9  96.6    -0.6   1468  7.5
 19500   -7.7  18.1   285   14    7   8.4   4.6   35.5  95.9    -1.0   1421  7.2
 19000   -6.8  19.8   285   12    6   4.9   2.7   35.0  95.0    -1.4   1376  7.0
 18500   -5.7  21.7   285   10    5   7.8   4.3   34.5  94.2    -1.9   1330  6.8
 18000   -4.4  24.1   285    8    4   9.6   5.3   34.4  93.9    -2.0   1275  6.5
 17500   -3.0  26.6   290    6    3   9.5   5.2   34.3  93.8    -2.1   1218  6.2
 17000   -1.5  29.3   295    3    2   9.5   5.2   34.3  93.8    -2.1   1161  5.9
 16500   -0.1  31.8   305    3    2   9.5   5.2   34.3  93.7    -2.1   1103  5.6
 16000    2.0  35.6   315    3    2   9.4   5.2   34.2  93.6    -2.2   1017  5.2
 15500    3.4  38.1   305    4    2   9.3   5.1   34.1  93.4    -2.3    961  4.9
 15000    4.8  40.6   295    4    2   9.3   5.1   34.1  93.3    -2.4    905  4.6
 14500    6.1  43.0   290    5    3   9.3   5.1   34.0  93.3    -2.5    849  4.3
 14000    7.5  45.5   285    6    3   9.3   5.1   34.0  93.2    -2.5    793  4.0
 13500    8.9  48.0   285    7    4   9.3   5.1   33.9  93.0    -2.7    737  3.7
 13000   10.2  50.4   285    9    4   9.3   5.1   33.8  92.9    -2.8    681  3.5
 12500   11.6  52.9   285   10    5   9.3   5.1   33.8  92.8    -2.9    625  3.2
 12000   13.0  55.4   285   11    6   9.3   5.1   33.7  92.7    -2.9    569  2.9
 11500   14.4  57.9   290   12    6   9.3   5.1   33.6  92.5    -3.1    514  2.6
 11000   15.7  60.3   295   12    6   9.3   5.1   33.5  92.3    -3.2    458  2.3
 10500   17.1  62.8   280   13    7   8.9   4.9   33.4  92.2    -3.3    402  2.0
 10250   17.7  63.9   275   14    7   8.3   4.5   33.3  91.9    -3.5    376  1.9
 10000   18.3  64.9   275   14    7   8.3   4.6   33.2  91.7    -3.6    350  1.8
  9750   18.9  66.0   270   15    8   8.3   4.6   33.1  91.5    -3.7    324  1.6
  9500   19.6  67.3   270   16    8   8.2   4.5   33.0  91.3    -3.9    298  1.5
  9250   20.2  68.4   265   16    8   8.8   4.8   32.8  91.1    -4.0    272  1.4
  9000   20.8  69.4   265   17    9   6.5   3.6   32.7  90.9    -4.1    247  1.3
  8750   21.1  70.0   260   18    9   4.1   2.2   32.3  90.2    -4.5    229  1.2
  8500   21.4  70.5   255   20   10   4.6   2.5   31.9  89.5    -4.9    212  1.1
  8250   21.8  71.2   255   21   11   4.6   2.5   31.5  88.8    -5.3    195  1.0
  8000   22.1  71.8   250   23   12   4.3   2.4   31.1  88.1    -5.7    178  0.9
  7750   22.4  72.3   250   21   11   6.4   3.5   30.8  87.4    -6.1    160  0.8
  7500   23.0  73.4   250   20   10   8.4   4.6   30.6  87.1    -6.3    135  0.7
  7250   23.6  74.5   245   18    9   7.7   4.2   30.5  86.9    -6.5    110  0.6
  7000   24.2  75.6   245   16    8   8.4   4.6   30.3  86.6    -6.6     86  0.4
  6750   24.8  76.6   245   15    7   6.3   3.5   30.2  86.4    -6.8     61  0.3
  6500   24.7  76.5   240   13    7 -12.8  -7.0   29.4  84.9    -7.7     57  0.3
  6250   23.1  73.6   240   12    6 -16.6  -9.1   27.2  80.9    -9.9     95  0.5
  6000   22.5  72.5   235   10    5  -1.4  -0.8   25.9  78.6   -11.3    106  0.5
  5750   22.4  72.3   235    7    4  -1.2  -0.7   25.1  77.2   -12.2    102  0.5
  5500   21.6  70.9   235    3    2 -23.5 -12.9   23.7  74.6   -13.8    120  0.6

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

           07/07/2014 at 0900 MDT          |       07/07/2014 at 1200 MDT
                                           |
K index... +22.1  LI... -0.6               | K index... +22.5  LI... -1.6
CAPE... +104.9  CIN... -79.0               | CAPE... +243.2  CIN... -28.7
                                           |
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  345  13  7   0.8   0.4 | -66.9 -88.4  315  12  6   0.9   0.5
 45000 -62.3 -80.1  340  18  9   6.6   3.6 | -62.5 -80.5  320  15  8   6.8   3.7
 40000 -52.4 -62.3  340  22 11   6.9   3.8 | -52.2 -62.0  330  19 10   7.3   4.0
 38000 -48.2 -54.8  335  23 12   6.9   3.8 | -47.9 -54.2  335  19 10   7.3   4.0
 36000 -44.1 -47.4  330  24 12   6.9   3.8 | -43.5 -46.3  340  20 10   7.3   4.0
 34000 -39.8 -39.6  320  23 12   7.2   3.9 | -39.2 -38.6  325  21 11   7.1   3.9
 32000 -34.9 -30.8  305  22 12   7.5   4.1 | -34.5 -30.1  315  23 12   7.4   4.1
 30000 -30.4 -22.7  300  19 10   7.5   4.1 | -29.8 -21.6  310  22 11   7.8   4.3
 29000 -28.2 -18.8  300  17  9   7.5   4.1 | -27.5 -17.5  310  21 11   7.8   4.3
 28000 -26.0 -14.8  295  15  8   6.6   3.6 | -25.2 -13.4  310  20 10   6.7   3.7
 27000 -24.0 -11.2  290  14  7   6.7   3.7 | -23.2  -9.8  310  19 10   6.8   3.7
 26000 -22.0  -7.6  285  13  7   6.7   3.7 | -21.2  -6.2  310  18  9   6.8   3.7
 25000 -20.0  -4.0  280  12  6   7.2   3.9 | -19.1  -2.4  310  16  8   7.0   3.8
 24000 -17.8  -0.0  280  11  6   7.6   4.2 | -17.0   1.4  305  15  8   7.2   3.9
 23000 -15.5   4.1  285  11  6   7.6   4.2 | -14.9   5.2  305  14  7   7.2   4.0
 22000 -13.2   8.2  285  11  6   7.4   4.1 | -12.7   9.1  300  13  7   7.1   3.9
 21000 -11.1  12.0  285  12  6   7.3   4.0 | -10.7  12.7  295  14  7   7.1   3.9
 20000  -9.0  15.8  290  12  6   7.4   4.0 |  -8.7  16.3  290  14  7   7.1   3.9
 19500  -7.9  17.8  290  13  6   7.5   4.1 |  -7.6  18.3  290  14  7   7.2   4.0
 19000  -6.7  19.9  290  13  7   8.8   4.9 |  -6.5  20.3  285  14  7   8.7   4.8
 18500  -5.4  22.3  290  13  7   8.8   4.8 |  -5.2  22.6  285  14  7   8.6   4.7
 18000  -4.1  24.6  290  13  7   9.1   5.0 |  -3.9  25.0  285  13  7   8.8   4.8
 17500  -2.8  27.0  295  13  6   9.2   5.1 |  -2.6  27.3  285  13  7   8.9   4.9
 17000  -1.4  29.5  295  12  6   9.2   5.1 |  -1.3  29.7  285  12  6   9.0   4.9
 16500  -0.0  32.0  300  12  6   9.2   5.0 |   0.1  32.2  285  12  6   9.3   5.1
 16000   2.0  35.6  305  11  6   9.2   5.1 |   2.1  35.8  285  12  6   9.3   5.1
 15500   3.4  38.1  305  11  6   9.3   5.1 |   3.5  38.3  285  11  6   9.1   5.0
 15000   4.8  40.6  310  11  6   9.3   5.1 |   4.8  40.6  285  11  6   9.1   5.0
 14500   6.2  43.2  310  11  6   9.5   5.2 |   6.2  43.2  285  10  5   9.5   5.2
 14000   7.6  45.7  310  11  6   9.5   5.2 |   7.6  45.7  285  10  5   9.5   5.2
 13500   9.0  48.2  310  11  6   9.3   5.1 |   9.0  48.2  285  10  5   9.2   5.0
 13000  10.3  50.5  305  10  5   9.3   5.1 |  10.3  50.5  290  10  5   9.1   5.0
 12500  11.7  53.1  305  10  5   9.3   5.1 |  11.7  53.1  290  10  5   9.2   5.1
 12000  13.1  55.6  300  10  5   9.4   5.1 |  13.1  55.6  295  11  6   9.3   5.1
 11500  14.5  58.1  300  10  5   9.2   5.0 |  14.4  57.9  295  11  6   9.3   5.1
 11000  15.8  60.4  295  11  5   8.7   4.8 |  15.8  60.4  300  12  6   9.0   4.9
 10500  17.2  63.0  295  11  6   4.8   2.6 |  17.2  63.0  300  13  6   5.3   2.9
 10250  17.4  63.3  295  11  6   5.6   3.1 |  17.4  63.3  300  12  6   6.1   3.3
 10000  18.1  64.6  295  12  6  11.4   6.3 |  18.2  64.8  305  12  6  11.6   6.3
  9750  18.9  66.0  295  12  6  10.3   5.7 |  19.0  66.2  305  12  6  10.5   5.7
  9500  19.6  67.3  290  13  7   9.1   5.0 |  19.7  67.5  305  12  6   9.5   5.2
  9250  20.2  68.4  290  13  7   7.9   4.3 |  20.4  68.7  305  11  6   9.1   5.0
  9000  20.9  69.6  290  13  7   9.3   5.1 |  21.1  70.0  305  11  6  10.7   5.8
  8750  21.6  70.9  290  14  7   9.4   5.2 |  21.9  71.4  300  11  5  10.5   5.8
  8500  22.3  72.1  290  14  7   9.2   5.0 |  22.6  72.7  300  10  5  10.7   5.9
  8250  22.9  73.2  285  14  7   8.9   4.9 |  23.4  74.1  300  10  5  11.0   6.0
  8000  23.6  74.5  280  13  7   9.2   5.0 |  24.2  75.6  300  10  5   9.9   5.5
  7750  24.2  75.6  280  13  7   9.4   5.2 |  24.9  76.8  300  10  5   9.1   5.0
  7500  24.9  76.8  280  13  7   8.3   4.6 |  25.6  78.1  300  10  5   9.9   5.4
  7250  25.5  77.9  280  13  7   7.5   4.1 |  26.4  79.5  300  10  5  10.5   5.7
  7000  26.0  78.8  285  13  7   7.8   4.3 |  27.2  81.0  300  10  5  10.0   5.5
  6750  26.6  79.9  285  13  7   5.6   3.1 |  27.9  82.2  300  10  5   9.9   5.4
  6500  26.8  80.2  290  12  6  -0.4  -0.2 |  28.7  83.7  300  10  5  10.8   5.9
  6250  26.5  79.7  285  10  5  -1.5  -0.8 |  29.5  85.1  300   9  5  11.9   6.5
  6000  26.3  79.3  285   7  4  -5.5  -3.0 |  30.4  86.7  300   9  5   9.8   5.4
  5750  25.7  78.3  270   4  2  -0.9  -0.5 |  31.1  88.0  300   9  5  13.6   7.4
  5500  26.5  79.7  255   3  2  23.3  12.8 |  32.6  90.7  300   9  5  27.1  14.9

           07/07/2014 at 1500 MDT          |       07/07/2014 at 1800 MDT
                                           |
K index... +22.6  LI... -0.5               | K index... +18.8  LI... +0.2
CAPE... +98.4  CIN... -31.0                | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.7 -88.1  295  15  8   0.8   0.4 | -66.9 -88.4  300  20 10   0.7   0.4
 45000 -62.6 -80.7  300  17  9   6.7   3.7 | -62.8 -81.0  295  25 13   6.8   3.7
 40000 -52.4 -62.3  310  21 11   7.5   4.1 | -52.4 -62.3  310  23 12   7.5   4.1
 38000 -47.9 -54.2  320  19 10   7.5   4.1 | -47.9 -54.2  310  22 11   7.4   4.1
 36000 -43.4 -46.1  325  18  9   7.5   4.1 | -43.5 -46.3  315  20 10   7.6   4.1
 34000 -38.1 -36.6  320  18  9   7.9   4.3 | -37.8 -36.0  310  20 10   8.5   4.7
 32000 -33.3 -27.9  315  19 10   7.7   4.2 | -32.7 -26.9  305  20 10   8.0   4.4
 30000 -29.3 -20.7  310  20 10   6.6   3.6 | -28.8 -19.8  310  21 11   6.5   3.6
 29000 -27.3 -17.1  310  20 10   6.6   3.6 | -26.8 -16.2  310  21 11   6.5   3.6
 28000 -25.2 -13.4  315  20 10   7.6   4.2 | -24.8 -12.6  310  21 11   6.8   3.8
 27000 -23.0  -9.4  315  20 10   7.5   4.1 | -22.8  -9.0  310  21 11   6.8   3.7
 26000 -20.8  -5.4  315  19 10   7.5   4.1 | -20.8  -5.4  315  20 10   6.9   3.8
 25000 -18.5  -1.3  315  19 10   7.3   4.0 | -18.8  -1.8  315  19 10   7.0   3.8
 24000 -16.4   2.5  310  18  9   7.0   3.8 | -16.7   1.9  315  19 10   7.1   3.9
 23000 -14.4   6.1  305  17  9   7.0   3.8 | -14.5   5.9  310  19 10   7.2   3.9
 22000 -12.3   9.9  300  17  9   7.1   3.9 | -12.4   9.7  310  19 10   7.1   3.9
 21000 -10.2  13.6  305  17  9   7.2   4.0 | -10.4  13.3  315  20 10   7.0   3.9
 20000  -8.1  17.4  310  18  9   7.3   4.0 |  -8.3  17.1  315  22 11   7.1   3.9
 19500  -7.0  19.4  310  18  9   7.4   4.1 |  -7.3  18.9  320  23 12   7.2   4.0
 19000  -5.8  21.6  310  19 10   9.2   5.1 |  -6.1  21.0  320  22 12   9.2   5.0
 18500  -4.5  23.9  310  20 10   9.1   5.0 |  -4.8  23.4  320  22 11   9.0   5.0
 18000  -3.1  26.4  310  22 11   8.9   4.9 |  -3.5  25.7  320  21 11   9.2   5.1
 17500  -1.8  28.8  310  22 11   8.8   4.8 |  -2.1  28.2  320  20 11   9.4   5.1
 17000  -0.6  30.9  310  22 11   8.8   4.8 |  -0.7  30.7  325  20 10   9.4   5.1
 16500   1.3  34.3  310  21 11   8.5   4.6 |   1.5  34.7  330  18  9   9.5   5.2
 16000   2.5  36.5  310  21 11   8.6   4.7 |   2.9  37.2  330  17  9   9.4   5.2
 15500   3.8  38.8  310  20 10   9.2   5.0 |   4.2  39.6  335  16  8   8.9   4.9
 15000   5.2  41.4  310  19 10   9.2   5.0 |   5.6  42.1  340  14  7   8.9   4.9
 14500   6.5  43.7  315  18  9   9.1   5.0 |   6.9  44.4  345  13  7   9.3   5.1
 14000   7.9  46.2  315  16  8   9.1   5.0 |   8.3  46.9  350  13  7   9.3   5.1
 13500   9.2  48.6  315  14  7   9.2   5.1 |   9.7  49.5  350  12  6   9.0   4.9
 13000  10.6  51.1  310  13  7   9.2   5.1 |  11.0  51.8  355  12  6   8.9   4.9
 12500  11.9  53.4  310  11  6   9.5   5.2 |  12.3  54.1  355  11  6   9.1   5.0
 12000  13.4  56.1  310  11  6   9.8   5.4 |  13.6  56.5  355  11  6   9.2   5.1
 11500  14.8  58.6  310  11  5   9.7   5.3 |  15.0  59.0  355  11  6   9.4   5.1
 11000  16.3  61.3  310  10  5   9.4   5.2 |  16.4  61.5  355  11  6   9.4   5.1
 10500  17.7  63.9  310  10  5   6.5   3.6 |  17.8  64.0  355  11  6   7.2   3.9
 10250  18.1  64.6  310  10  5   7.6   4.2 |  18.3  64.9  360  11  6   8.2   4.5
 10000  19.0  66.2  310  10  5  12.3   6.7 |  19.1  66.4  355  11  6  11.8   6.5
  9750  19.8  67.6  310  10  5  11.5   6.3 |  20.0  68.0  355  11  6  11.2   6.1
  9500  20.7  69.3  310  10  5  10.0   5.5 |  20.8  69.4  355  11  6   9.9   5.5
  9250  21.3  70.3  310  10  5   9.0   4.9 |  21.5  70.7  355  11  6   9.2   5.1
  9000  22.1  71.8  305  10  5  10.4   5.7 |  22.2  72.0  355  11  6  10.5   5.7
  8750  22.9  73.2  305  10  5  10.2   5.6 |  23.0  73.4  355  11  6  10.4   5.7
  8500  23.6  74.5  305  10  5  10.6   5.8 |  23.8  74.8  355  11  6  10.2   5.6
  8250  24.4  75.9  305  10  5  11.0   6.0 |  24.5  76.1  355  11  6  10.0   5.5
  8000  25.2  77.4  305  10  5  10.0   5.5 |  25.3  77.5  355  11  6   9.8   5.4
  7750  25.9  78.6  305  10  5   9.0   4.9 |  26.0  78.8  355  11  6   9.6   5.3
  7500  26.6  79.9  305  10  5  10.0   5.5 |  26.7  80.1  355  11  6   9.9   5.4
  7250  27.4  81.3  305  10  5  10.7   5.9 |  27.5  81.5  355  11  6  10.1   5.5
  7000  28.2  82.8  305  10  5  10.4   5.7 |  28.2  82.8  355  11  6  10.1   5.5
  6750  29.0  84.2  305  10  5  10.2   5.6 |  29.0  84.2  355  11  6  10.2   5.6
  6500  29.7  85.5  305  10  5  10.4   5.7 |  29.7  85.5  355  11  6  10.2   5.6
  6250  30.5  86.9  305   9  5  11.1   6.1 |  30.5  86.9  355  11  5  10.4   5.7
  6000  31.3  88.3  305   9  5   9.5   5.2 |  31.3  88.3  355  10  5   9.8   5.4
  5750  32.1  89.8  305   9  5  13.5   7.4 |  32.1  89.8  350  10  5  12.2   6.7
  5500  33.6  92.5  305   9  5  27.0  14.8 |  33.2  91.8  350  10  5  19.3  10.6
________________________________________________________________________________

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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