Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 091318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0718 MDT Wednesday, July 9, 2014

This forecast is for Wednesday, July 9, 2014:

If the trigger temperature of 85.7 F/29.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1111 ft/min (5.6 m/s)
   Maximum height of thermals.................. 18037 ft MSL (12752 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10359 ft MSL (5074 ft AGL)
Thermal soaring outlook for Thursday 07/10..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 17612 ft MSL (12327 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18105 ft MSL (12820 ft AGL)
Wave soaring outlook for Thursday 07/10........ Poor

Remarks... Strong upper level ridge centered over the four corners region with
           light northwest flow aloft over northeast colorado.

Sunrise/Sunset.................... 05:39:53 / 20:29:38 MDT
Total possible sunshine........... 14 hr 49 min 46 sec (889 min 46 sec)
Altitude of sun at 13:04:44 MDT... 72.49 degrees

Upper air data from rawinsonde observation taken on 07/09/2014 at 0600 MDT

Freezing level.................. 15941 ft MSL (10656 ft AGL)
Convective condensation level... 14864 ft MSL (9579 ft AGL)
Lifted condensation level....... 15817 ft MSL (10532 ft AGL)
Lifted index.................... -6.2
K index......................... +23.9

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  -66.7 -88.1   345   41   21   2.9   1.6   81.0 177.8    27.5      M    M
 45000  -59.6 -75.3   325   46   24   6.7   3.7   68.5 155.4    21.7      M    M
 40000  -53.0 -63.4   300   42   22   6.4   3.5   55.9 132.7    14.8      M    M
 38000  -50.8 -59.4   295   54   28   8.2   4.5   50.7 123.2    11.5      M    M
 36000  -45.7 -50.3   305   49   25   8.5   4.7   49.6 121.2    11.1      M    M
 34000  -40.2 -40.4   305   41   21   8.1   4.4   48.1 118.6    10.3      M    M
 32000  -35.3 -31.5   305   34   17   6.5   3.6   46.8 116.2     9.6      M    M
 30000  -30.5 -22.9   300   30   15   8.5   4.6   45.3 113.5     8.7      M    M
 29000  -28.0 -18.4   295   26   13   8.4   4.6   44.7 112.5     8.4      M    M
 28000  -25.5 -13.9   290   22   11   3.1   1.7   44.2 111.5     8.0      M    M
 27000  -24.2 -11.6   305   18    9   7.1   3.9   42.1 107.8     6.5      M    M
 26000  -22.0  -7.6   320   16    8   7.2   3.9   41.2 106.1     5.8      M    M
 25000  -19.9  -3.8   305   21   11   6.9   3.8   40.2 104.3     5.1      M    M
 24000  -18.0  -0.4   300   19   10   6.2   3.4   38.9 102.1     4.1      M    M
 23000  -16.1   3.0   315   10    5   6.1   3.4   37.6  99.8     3.1      M    M
 22000  -14.4   6.1   320   10    5   6.3   3.5   36.2  97.1     1.9      M    M
 21000  -12.1  10.2   320   10    5   8.1   4.4   35.5  95.9     1.3      M    M
 20000   -9.7  14.5   325   10    5   8.1   4.4   35.0  95.0     0.9      M    M
 19500   -8.5  16.7   320   11    5   8.0   4.4   34.7  94.4     0.6      M    M
 19000   -7.2  19.0   305   12    6   8.8   4.8   34.5  94.0     0.4      M    M
 18500   -5.9  21.4   310   15    8   8.7   4.8   34.3  93.7     0.2      M    M
 18000   -4.6  23.7   315   17    9   8.7   4.8   34.1  93.4     0.0      M    M
 17500   -3.9  25.0   320   19   10   2.9   1.6   33.4  92.1    -0.7   1180  6.0
 17000   -2.9  26.8   325   21   11  11.4   6.2   32.9  91.3    -1.2   1136  5.8
 16500   -1.3  29.7   330   19   10  10.2   5.6   32.5  90.5    -1.8   1065  5.4
 16000    0.2  32.4   330   17    9   9.6   5.2   32.5  90.5    -1.8   1008  5.1
 15500    1.6  34.9   330   16    8   9.5   5.2   32.4  90.4    -1.9    950  4.8
 15000    3.0  37.4   330   16    8   8.4   4.6   32.4  90.2    -2.0    894  4.5
 14500    4.2  39.6   330   15    8   9.6   5.3   32.2  89.9    -2.2    842  4.3
 14000    5.6  42.1   330   14    7   9.5   5.2   32.2  89.9    -2.3    786  4.0
 13500    7.0  44.6   330   12    6   9.5   5.2   32.1  89.8    -2.4    729  3.7
 13000    8.4  47.1   330    9    4   9.5   5.2   32.1  89.7    -2.4    672  3.4
 12500    9.8  49.6   330    6    3   9.6   5.2   32.1  89.7    -2.5    615  3.1
 12000   11.2  52.2   325    3    2   9.6   5.2   32.1  89.7    -2.6    558  2.8
 11500   12.6  54.7   305    4    2   9.6   5.3   32.0  89.6    -2.7    501  2.5
 11000   14.0  57.2   295    5    2   9.6   5.3   31.9  89.5    -2.7    445  2.3
 10500   15.3  59.5   290    6    3   8.1   4.4   31.8  89.3    -2.9    391  2.0
 10250   15.8  60.4   290    7    3   7.3   4.0   31.7  89.0    -3.1    367  1.9
 10000   16.4  61.5   290    7    4   7.4   4.0   31.5  88.6    -3.3    343  1.7
  9750   16.9  62.4   295    8    4   7.4   4.0   31.3  88.3    -3.5    320  1.6
  9500   17.4  63.3   295    9    4   7.3   4.0   31.1  88.0    -3.7    297  1.5
  9250   18.0  64.4   295    9    5   7.7   4.2   30.9  87.6    -3.9    273  1.4
  9000   18.5  65.3   295   10    5   6.3   3.4   30.7  87.3    -4.1    250  1.3
  8750   18.9  66.0   295    9    4   4.5   2.5   30.4  86.7    -4.5    232  1.2
  8500   19.2  66.6   300    7    4   4.5   2.5   30.0  85.9    -4.9    214  1.1
  8250   19.5  67.1   300    6    3   5.1   2.8   29.6  85.2    -5.3    197  1.0
  8000   19.7  67.5   305    5    3  -2.5  -1.3   29.1  84.3    -5.9    184  0.9
  7750   19.2  66.6   305    4    2  -3.4  -1.9   27.9  82.2    -7.2    193  1.0
  7500   19.4  66.9   310    3    2  10.4   5.7   27.4  81.3    -7.7    179  0.9
  7250   19.9  67.8   315    3    1  -2.9  -1.6   27.3  81.1    -7.9    155  0.8
  7000   18.6  65.5   325    2    1  -8.0  -4.4   25.7  78.2   -10.0    188  1.0
  6750   18.6  65.5   305    1    1   2.9   1.6   25.0  76.9   -10.7    180  0.9
  6500   18.7  65.7   270    1    1  -0.1  -0.0   24.3  75.7   -11.5    171  0.9
  6250   18.7  65.7   230    1    1   0.8   0.4   23.6  74.4   -12.2    163  0.8
  6000   18.7  65.7   210    2    1   0.4   0.2   22.9  73.2   -12.9    154  0.8
  5750   18.8  65.8   210    1    1   1.2   0.6   22.2  72.0   -13.6    146  0.7
  5500   18.6  65.5   210    1    0  -9.2  -5.1   21.3  70.4   -14.5    143  0.7

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

           07/09/2014 at 0900 MDT          |       07/09/2014 at 1200 MDT
                                           |
K index... +22.1  LI... -1.7               | K index... +23.8  LI... -3.6
CAPE... +314.5  CIN... -178.9              | CAPE... +857.8  CIN... -18.4
                                           |
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 -64.1 -83.4  345  31 16   2.6   1.4 | -64.5 -84.1  345  29 15   2.7   1.5
 45000 -58.8 -73.8  335  41 21   5.6   3.1 | -59.0 -74.2  335  37 19   5.8   3.2
 40000 -50.2 -58.4  315  45 23   4.4   2.4 | -50.1 -58.2  325  41 21   4.9   2.7
 38000 -47.6 -53.7  305  44 23   4.4   2.4 | -47.2 -53.0  315  41 21   4.9   2.7
 36000 -45.0 -49.0  300  44 23   4.4   2.4 | -44.2 -47.6  305  43 22   4.8   2.7
 34000 -40.5 -40.9  300  40 20   7.8   4.3 | -40.1 -40.2  305  41 21   7.2   3.9
 32000 -35.9 -32.6  300  34 18   7.6   4.2 | -35.8 -32.4  305  39 20   7.0   3.8
 30000 -31.2 -24.2  305  29 15   7.8   4.3 | -31.1 -24.0  305  35 18   8.0   4.4
 29000 -28.3 -18.9  305  26 13   7.8   4.3 | -28.1 -18.6  305  32 17   8.0   4.4
 28000 -26.1 -15.0  310  24 12   6.1   3.4 | -25.9 -14.6  305  30 15   6.3   3.5
 27000 -24.1 -11.4  305  22 11   6.3   3.5 | -23.9 -11.0  305  28 14   6.5   3.6
 26000 -22.2  -8.0  300  20 10   6.3   3.5 | -21.9  -7.4  305  25 13   6.5   3.6
 25000 -20.3  -4.5  295  19 10   7.1   3.9 | -20.0  -4.0  305  23 12   6.8   3.7
 24000 -18.0  -0.4  290  18  9   7.9   4.3 | -17.8  -0.0  305  22 11   7.2   4.0
 23000 -15.6   3.9  290  17  9   7.9   4.3 | -15.7   3.7  300  21 11   7.2   4.0
 22000 -13.3   8.1  285  16  8   7.3   4.0 | -13.5   7.7  300  21 11   7.2   4.0
 21000 -11.2  11.8  295  14  7   6.9   3.8 | -11.4  11.5  300  19 10   7.3   4.0
 20000  -9.2  15.4  305  13  7   7.0   3.8 |  -9.3  15.3  300  17  9   7.5   4.1
 19500  -8.2  17.2  315  13  7   7.1   3.9 |  -8.2  17.2  300  16  8   7.6   4.2
 19000  -7.1  19.2  320  13  7   7.6   4.2 |  -7.1  19.2  300  16  8   7.6   4.2
 18500  -6.1  21.0  325  12  6   7.7   4.2 |  -6.0  21.2  305  15  8   7.6   4.2
 18000  -5.0  23.0  330  12  6   8.5   4.7 |  -4.9  23.2  305  15  7   8.4   4.6
 17500  -3.7  25.3  335  13  7   8.8   4.9 |  -3.7  25.3  310  14  7   8.7   4.8
 17000  -2.4  27.7  340  14  7   9.0   4.9 |  -2.4  27.7  310  14  7   8.8   4.8
 16500  -1.1  30.0  345  14  7   9.2   5.0 |  -1.1  30.0  315  13  7   9.3   5.1
 16000   0.2  32.4  345  14  7   9.2   5.0 |   0.3  32.5  315  12  6   9.3   5.1
 15500   1.5  34.7  345  14  7   9.1   5.0 |   1.6  34.9  315  11  6   9.2   5.1
 15000   2.9  37.2  345  14  7   9.1   5.0 |   3.0  37.4  315  10  5   9.2   5.1
 14500   4.9  40.8  345  13  7   9.2   5.1 |   5.0  41.0  315   8  4   9.1   5.0
 14000   6.3  43.3  345  12  6   9.2   5.1 |   6.3  43.3  315   7  4   9.1   5.0
 13500   7.6  45.7  345  12  6   9.2   5.0 |   7.7  45.9  315   6  3   8.9   4.9
 13000   9.0  48.2  340  11  6   9.2   5.0 |   9.0  48.2  315   6  3   8.8   4.8
 12500  10.3  50.5  335  11  5   8.7   4.8 |  10.3  50.5  315   6  3   8.9   4.9
 12000  11.6  52.9  325  10  5   8.5   4.7 |  11.6  52.9  310   7  3   8.9   4.9
 11500  12.8  55.0  315  10  5   8.2   4.5 |  12.9  55.2  305   7  4   8.9   4.9
 11000  13.9  57.0  310   9  5   7.6   4.2 |  14.2  57.6  310   7  4   8.6   4.7
 10500  15.1  59.2  305   9  5   4.3   2.3 |  15.5  59.9  315   8  4   5.3   2.9
 10250  15.3  59.5  305   9  5   5.5   3.0 |  15.8  60.4  315   8  4   6.9   3.8
 10000  16.0  60.8  300  10  5  10.8   5.9 |  16.6  61.9  315   8  4  12.5   6.9
  9750  16.7  62.1  300  10  5  10.0   5.5 |  17.4  63.3  315   9  4  11.6   6.4
  9500  17.4  63.3  300  11  6   8.2   4.5 |  18.3  64.9  315   9  5   9.6   5.3
  9250  17.9  64.2  300  11  6   6.9   3.8 |  18.8  65.8  315   9  5   7.3   4.0
  9000  18.5  65.3  300  12  6   9.1   5.0 |  19.3  66.7  315   8  4   8.6   4.7
  8750  19.2  66.6  300  13  7   9.7   5.3 |  19.9  67.8  310   8  4   8.5   4.7
  8500  19.9  67.8  300  14  7   8.0   4.4 |  20.4  68.7  305   7  3   8.9   4.9
  8250  20.4  68.7  300  15  8   6.7   3.7 |  21.1  70.0  300   6  3   9.3   5.1
  8000  20.9  69.6  300  16  8   7.1   3.9 |  21.7  71.1  290   5  3   9.4   5.2
  7750  21.3  70.3  300  17  9   6.7   3.7 |  22.4  72.3  290   5  3   9.7   5.3
  7500  21.8  71.2  300  17  9   5.5   3.0 |  23.1  73.6  290   5  3  10.1   5.6
  7250  22.1  71.8  295  15  8   4.6   2.5 |  23.9  75.0  290   5  3  10.8   5.9
  7000  22.4  72.3  295  14  7   5.2   2.8 |  24.7  76.5  290   5  3   9.9   5.4
  6750  22.8  73.0  290  12  6   4.9   2.7 |  25.4  77.7  290   5  3   9.5   5.2
  6500  23.0  73.4  285  10  5   3.3   1.8 |  26.2  79.2  290   5  3  10.6   5.8
  6250  23.2  73.8  280   8  4   3.9   2.2 |  27.0  80.6  290   5  2  12.0   6.6
  6000  23.4  74.1  265   6  3   0.8   0.5 |  27.8  82.0  290   5  2   9.1   5.0
  5750  23.4  74.1  220   4  2   6.5   3.6 |  28.5  83.3  290   5  2  13.9   7.6
  5500  24.5  76.1  220   4  2  25.3  13.9 |  30.1  86.2  290   5  2  30.5  16.8

           07/09/2014 at 1500 MDT          |       07/09/2014 at 1800 MDT
                                           |
K index... +26.0  LI... -2.3               | K index... +27.9  LI... -1.7
CAPE... +522.1  CIN... -14.8               | CAPE... +264.9  CIN... -13.2
                                           |
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 -65.1 -85.2  345  32 16   2.1   1.1 | -64.6 -84.3  345  33 17   2.1   1.2
 45000 -59.5 -75.1  335  40 21   6.4   3.5 | -59.3 -74.7  340  43 22   5.8   3.2
 40000 -50.0 -58.0  325  41 21   5.5   3.0 | -50.5 -58.9  325  41 21   6.4   3.5
 38000 -46.7 -52.1  310  42 22   5.5   3.0 | -46.6 -51.9  320  41 21   6.4   3.5
 36000 -43.4 -46.1  300  44 23   5.6   3.1 | -42.7 -44.9  315  41 21   6.5   3.5
 34000 -39.3 -38.7  300  42 22   6.9   3.8 | -38.6 -37.5  310  41 21   6.9   3.8
 32000 -35.2 -31.4  300  39 20   6.7   3.7 | -34.5 -30.1  305  40 21   6.7   3.7
 30000 -30.0 -22.0  305  37 19   7.9   4.3 | -29.4 -20.9  310  33 17   7.7   4.2
 29000 -27.6 -17.7  305  36 18   7.9   4.4 | -27.1 -16.8  315  29 15   7.8   4.3
 28000 -25.3 -13.5  310  34 18   6.4   3.5 | -24.9 -12.8  320  26 13   6.7   3.7
 27000 -23.3  -9.9  310  31 16   6.6   3.6 | -22.9  -9.2  320  23 12   6.8   3.7
 26000 -21.3  -6.3  315  27 14   6.6   3.6 | -20.9  -5.6  320  20 10   6.8   3.7
 25000 -19.4  -2.9  320  24 12   6.9   3.8 | -18.9  -2.0  325  17  9   6.9   3.8
 24000 -17.2   1.0  315  23 12   7.2   3.9 | -16.8   1.8  330  17  9   7.1   3.9
 23000 -15.1   4.8  315  21 11   7.2   3.9 | -14.7   5.5  330  16  8   7.1   3.9
 22000 -12.9   8.8  315  20 10   7.2   4.0 | -12.6   9.3  330  16  8   7.2   3.9
 21000 -10.8  12.6  315  18 10   7.3   4.0 | -10.5  13.1  335  14  7   7.2   4.0
 20000  -8.6  16.5  315  17  9   7.4   4.0 |  -8.4  16.9  345  13  7   7.3   4.0
 19500  -7.6  18.3  315  16  8   7.5   4.1 |  -7.3  18.9  345  12  6   7.3   4.0
 19000  -6.4  20.5  320  15  8   8.0   4.4 |  -6.2  20.8  350  12  6   7.1   3.9
 18500  -5.3  22.5  320  14  7   8.0   4.4 |  -5.2  22.6  355  11  6   7.1   3.9
 18000  -4.2  24.4  320  14  7   8.6   4.7 |  -4.2  24.4  360  10  5   7.3   4.0
 17500  -2.9  26.8  320  13  7   8.8   4.8 |  -3.1  26.4  360   9  5   7.5   4.1
 17000  -1.6  29.1  320  12  6   8.9   4.9 |  -2.0  28.4  360   8  4   7.6   4.2
 16500  -0.3  31.5  325  11  6   8.8   4.8 |  -0.9  30.4  360   7  3   7.2   3.9
 16000   0.9  33.6  325  10  5   8.8   4.8 |   0.1  32.2  360   5  3   7.2   3.9
 15500   2.2  36.0  325   8  4   9.0   4.9 |   1.8  35.2  350   3  2   8.6   4.7
 15000   4.2  39.6  330   6  3   9.0   5.0 |   3.0  37.4  335   2  1   8.4   4.6
 14500   5.5  41.9  335   5  3   8.9   4.9 |   4.4  39.9  320   2  1   9.9   5.4
 14000   6.8  44.2  340   4  2   8.9   4.9 |   5.8  42.4  310   2  1   9.9   5.4
 13500   8.1  46.6  345   3  1   9.2   5.0 |   7.3  45.1  305   2  1   9.7   5.3
 13000   9.5  49.1  340   2  1   9.2   5.1 |   8.7  47.7  300   2  1   9.6   5.3
 12500  10.8  51.4  335   1  1   9.2   5.1 |  10.2  50.4  295   2  1   9.7   5.3
 12000  12.2  54.0  320   1  0   9.3   5.1 |  11.6  52.9  290   2  1   9.8   5.4
 11500  13.5  56.3  285   1  0   9.3   5.1 |  13.1  55.6  290   3  1   9.8   5.4
 11000  14.8  58.6  275   1  0   9.1   5.0 |  14.6  58.3  285   3  2   9.5   5.2
 10500  16.2  61.2  265   1  1   6.7   3.7 |  16.0  60.8  285   3  2   5.7   3.2
 10250  16.6  61.9  265   1  1   8.0   4.4 |  16.3  61.3  285   3  2   6.8   3.7
 10000  17.4  63.3  265   1  1  12.2   6.7 |  17.1  62.8  280   4  2  12.5   6.9
  9750  18.3  64.9  265   1  1  11.5   6.3 |  18.0  64.4  275   4  2  11.4   6.3
  9500  19.1  66.4  265   1  1  10.0   5.5 |  18.8  65.8  275   4  2  10.2   5.6
  9250  19.7  67.5  265   1  1   8.9   4.9 |  19.5  67.1  270   5  2   8.8   4.8
  9000  20.5  68.9  265   1  1  10.5   5.7 |  20.2  68.4  270   5  3   9.8   5.4
  8750  21.3  70.3  265   2  1  10.4   5.7 |  20.9  69.6  265   6  3   9.9   5.4
  8500  22.0  71.6  260   2  1  10.3   5.7 |  21.6  70.9  265   6  3   9.6   5.3
  8250  22.8  73.0  265   2  1  10.2   5.6 |  22.3  72.1  260   7  4   9.2   5.1
  8000  23.5  74.3  265   2  1   9.8   5.4 |  22.9  73.2  260   8  4   9.6   5.2
  7750  24.3  75.7  265   2  1   9.5   5.2 |  23.7  74.7  260   8  4   9.8   5.4
  7500  25.0  77.0  265   2  1   9.9   5.4 |  24.4  75.9  260   9  4   9.8   5.4
  7250  25.7  78.3  265   2  1  10.0   5.5 |  25.1  77.2  260   9  5   9.8   5.4
  7000  26.5  79.7  265   2  1  10.4   5.7 |  25.8  78.4  260   9  5   9.8   5.4
  6750  27.3  81.1  265   2  1  11.1   6.1 |  26.6  79.9  260  10  5  10.0   5.5
  6500  28.1  82.6  265   2  1  10.8   6.0 |  27.3  81.1  260  10  5  10.2   5.6
  6250  28.9  84.0  265   2  1  11.2   6.1 |  28.1  82.6  260  10  5  10.6   5.8
  6000  29.7  85.5  265   2  1   9.3   5.1 |  28.8  83.8  265  10  5   9.7   5.3
  5750  30.5  86.9  265   2  1  14.0   7.7 |  29.5  85.1  265  10  5  10.3   5.6
  5500  32.0  89.6  265   2  1  28.7  15.8 |  30.4  86.7  265   9  5  14.3   7.8
________________________________________________________________________________

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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