Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 181333
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0733 MDT Friday, July 18, 2014

This forecast is for Friday, July 18, 2014:

If the trigger temperature of 82.0 F/27.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 930 ft/min (4.7 m/s)
   Maximum height of thermals.................. 15788 ft MSL (10503 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 1030 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................. 12135 ft MSL (6849 ft AGL)
Thermal soaring outlook for Saturday 07/19..... Excellent

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)................ Weak PVA
Potential height of wave....................... 14389 ft MSL (9104 ft AGL)
Wave soaring outlook for Saturday 07/19........ Poor

Remarks...

Sunrise/Sunset.................... 05:46:26 / 20:25:10 MDT
Total possible sunshine........... 14 hr 38 min 44 sec (878 min 44 sec)
Altitude of sun at 13:05:41 MDT... 71.14 degrees

Upper air data from rawinsonde observation taken on 07/18/2014 at 0600 MDT

Freezing level.................. 16097 ft MSL (10812 ft AGL)
Convective condensation level... 16983 ft MSL (11698 ft AGL)
Lifted condensation level....... 16789 ft MSL (11503 ft AGL)
Lifted index.................... -1.2
K index......................... +8.6

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  -65.5 -85.9   310   27   14  -0.3  -0.2   84.2 183.6    30.2      M    M
 45000  -60.8 -77.4   295   37   19   1.1   0.6   66.4 151.6    21.4      M    M
 40000  -54.0 -65.2   295   44   22   6.4   3.5   54.5 130.1    14.9      M    M
 38000  -51.7 -61.1   295   42   22   1.3   0.7   49.2 120.6    11.7      M    M
 36000  -47.3 -53.1   295   28   15   9.0   4.9   47.2 116.9    10.6      M    M
 34000  -41.9 -43.4   300   27   14   9.3   5.1   46.4 115.6    10.3      M    M
 32000  -36.7 -34.1   295   23   12   8.7   4.7   45.6 114.1     9.9      M    M
 30000  -30.5 -22.9   290   27   14   9.0   4.9   45.2 113.3     9.9      M    M
 29000  -27.8 -18.0   290   26   13   8.6   4.7   44.8 112.7     9.7      M    M
 28000  -25.4 -13.7   290   25   13   8.0   4.4   44.1 111.4     9.2      M    M
 27000  -23.1  -9.6   285   25   13   8.0   4.4   43.4 110.2     8.8      M    M
 26000  -20.8  -5.4   285   24   12   6.9   3.8   42.6 108.7     8.3      M    M
 25000  -18.9  -2.0   285   23   12   5.1   2.8   41.5 106.7     7.4      M    M
 24000  -17.1   1.2   300   21   11   8.3   4.6   40.2 104.4     6.3      M    M
 23000  -14.5   5.9   295   23   12   8.6   4.7   39.8 103.6     6.1      M    M
 22000  -12.2  10.0   295   26   13   2.9   1.6   38.9 102.0     5.5      M    M
 21000  -11.6  11.1   305   22   11  -1.3  -0.7   36.1  97.0     3.3      M    M
 20000   -9.6  14.7   315   18    9   7.6   4.2   35.0  95.1     2.4      M    M
 19500   -8.5  16.7   310   18    9   7.6   4.2   34.7  94.4     2.1      M    M
 19000   -7.3  18.9   310   17    9   8.1   4.5   34.3  93.7     1.8      M    M
 18500   -6.1  21.0   310   15    8   8.2   4.5   34.0  93.2     1.5      M    M
 18000   -4.8  23.4   310   13    7   8.2   4.5   33.7  92.6     1.3      M    M
 17500   -3.6  25.5   310   11    6   8.2   4.5   33.4  92.2     1.0      M    M
 17000   -2.4  27.7   310    9    5   8.2   4.5   33.2  91.7     0.8      M    M
 16500   -1.2  29.8   305    7    4   7.9   4.3   33.0  91.3     0.6      M    M
 16000   -0.0  32.0   305    5    3   7.9   4.3   32.6  90.7     0.3      M    M
 15500    0.8  33.4   325    7    4   4.3   2.4   32.0  89.6    -0.3    918  4.7
 15000    1.8  35.2   340   12    6   8.2   4.5   30.9  87.7    -1.5    866  4.4
 14500    3.2  37.8   345   15    8   7.8   4.3   30.8  87.5    -1.6    810  4.1
 14000    4.0  39.2   350   18    9   7.1   3.9   30.3  86.6    -2.2    770  3.9
 13500    5.2  41.4   350   20   10   9.0   5.0   30.1  86.2    -2.6    722  3.7
 13000    6.5  43.7   350   22   11   8.9   4.9   30.0  85.9    -2.7    668  3.4
 12500    7.8  46.0   355   20   10   8.9   4.9   29.8  85.7    -2.9    614  3.1
 12000    9.1  48.4   355   18    9   8.9   4.9   29.7  85.4    -3.1    560  2.8
 11500   10.4  50.7   350   15    7   8.9   4.9   29.5  85.1    -3.3    506  2.6
 11000   11.7  53.1   345   12    6   8.9   4.9   29.4  84.9    -3.4    452  2.3
 10500   13.0  55.4   340    9    5   8.8   4.8   29.2  84.6    -3.6    398  2.0
 10250   13.6  56.5   335    8    4   8.2   4.5   29.1  84.5    -3.7    371  1.9
 10000   14.2  57.6   330    7    3   8.0   4.4   29.0  84.2    -3.9    347  1.8
  9750   14.8  58.6   320    6    3   8.0   4.4   28.9  84.0    -4.0    322  1.6
  9500   15.4  59.7   315    5    3   8.0   4.4   28.8  83.8    -4.2    297  1.5
  9250   16.0  60.8   305    4    2   8.0   4.4   28.6  83.5    -4.3    272  1.4
  9000   16.6  61.9   290    4    2   8.0   4.4   28.5  83.3    -4.5    247  1.3
  8750   17.1  62.8   275    6    3   8.1   4.4   28.4  83.1    -4.6    223  1.1
  8500   17.7  63.9   265    8    4   8.1   4.4   28.2  82.8    -4.8    198  1.0
  8250   18.3  64.9   265   10    5   8.1   4.4   28.1  82.6    -5.0    173  0.9
  8000   18.9  66.0   260   12    6   8.1   4.4   28.0  82.4    -5.1    148  0.8
  7750   19.5  67.1   260   12    6   8.1   4.4   27.9  82.1    -5.3    123  0.6
  7500   20.0  68.0   255   13    7   8.0   4.4   27.7  81.9    -5.5     98  0.5
  7250   20.6  69.1   255   13    7   8.3   4.6   27.6  81.7    -5.6     74  0.4
  7000   21.2  70.2   255   14    7   7.2   3.9   27.5  81.4    -5.8     49  0.2
  6750   21.6  70.9   240   15    8   5.7   3.1   27.2  80.9    -6.1     28  0.1
  6500   22.0  71.6   230   16    8   4.0   2.2   26.8  80.3    -6.5     10  0.1
  6250   22.0  71.6   225   18    9  -3.7  -2.0   26.2  79.1    -7.2      3  0.0
  6000   21.3  70.3   215   21   11  -8.7  -4.8   24.9  76.8    -8.7     17  0.1
  5750   20.2  68.4   215   14    7 -16.7  -9.2   23.3  73.9   -10.5     41  0.2
  5500   18.3  64.9   215    7    4 -31.8 -17.5   20.7  69.3   -13.2     92  0.5

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

           07/18/2014 at 0900 MDT          |       07/18/2014 at 1200 MDT
                                           |
K index... +21.7  LI... -0.5               | K index... +25.8  LI... -1.5
CAPE... +22.1  CIN... -93.3                | CAPE... +92.1  CIN... -4.6
                                           |
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 -63.4 -82.1  285  23 12   1.2   0.7 | -63.1 -81.6  280  25 13   1.1   0.6
 45000 -60.2 -76.4  295  37 19   4.1   2.2 | -60.2 -76.4  280  38 20   3.8   2.1
 40000 -53.6 -64.5  305  43 22   7.0   3.8 | -53.8 -64.8  285  48 25   7.7   4.2
 38000 -49.4 -56.9  305  42 22   7.1   3.9 | -49.1 -56.4  290  49 25   7.8   4.3
 36000 -45.1 -49.2  300  40 21   7.1   3.9 | -44.4 -47.9  295  51 26   7.9   4.3
 34000 -40.8 -41.4  300  37 19   7.4   4.0 | -40.1 -40.2  295  46 24   6.9   3.8
 32000 -36.3 -33.3  300  34 17   7.4   4.1 | -35.5 -31.9  290  40 20   6.7   3.7
 30000 -31.1 -24.0  295  30 15   7.8   4.3 | -30.9 -23.6  295  36 18   7.7   4.2
 29000 -28.8 -19.8  295  29 15   7.8   4.3 | -28.6 -19.5  295  34 18   7.7   4.3
 28000 -26.5 -15.7  295  27 14   7.7   4.2 | -26.3 -15.3  295  32 17   7.6   4.2
 27000 -24.2 -11.6  295  27 14   7.7   4.2 | -24.1 -11.4  295  33 17   7.6   4.2
 26000 -22.0  -7.6  290  27 14   7.7   4.2 | -21.9  -7.4  295  33 17   7.6   4.2
 25000 -19.7  -3.5  290  27 14   7.7   4.2 | -19.6  -3.3  295  34 17   7.5   4.1
 24000 -17.5   0.5  290  26 13   7.0   3.8 | -17.6   0.3  300  32 16   6.5   3.6
 23000 -15.4   4.3  295  24 13   7.0   3.9 | -15.7   3.7  300  29 15   6.5   3.6
 22000 -13.2   8.2  300  23 12   6.9   3.8 | -13.8   7.2  300  26 13   6.5   3.6
 21000 -11.4  11.5  305  21 11   6.1   3.4 | -11.9  10.6  300  22 11   6.3   3.5
 20000  -9.6  14.7  310  19 10   6.2   3.4 | -10.1  13.8  295  18  9   6.4   3.5
 19500  -8.6  16.5  310  18  9   6.2   3.4 |  -9.2  15.4  295  16  8   6.3   3.5
 19000  -7.8  18.0  315  17  9   5.6   3.1 |  -8.2  17.2  300  15  8   7.0   3.8
 18500  -7.0  19.4  320  16  8   5.7   3.1 |  -7.2  19.0  300  14  7   7.0   3.8
 18000  -6.2  20.8  325  16  8   6.1   3.3 |  -6.2  20.8  305  14  7   7.0   3.8
 17500  -5.2  22.6  330  16  8   7.1   3.9 |  -5.2  22.6  310  14  7   6.8   3.7
 17000  -4.3  24.3  335  16  8   7.0   3.9 |  -4.2  24.4  315  14  7   6.7   3.7
 16500  -3.2  26.2  340  16  8   8.8   4.8 |  -3.1  26.4  315  14  7   7.6   4.1
 16000  -1.9  28.6  340  16  8   8.9   4.9 |  -1.5  29.3  320  14  7   7.5   4.1
 15500   0.1  32.2  340  16  8   9.2   5.0 |  -0.3  31.5  320  15  8   9.1   5.0
 15000   1.4  34.5  335  16  8   9.2   5.0 |   1.0  33.8  320  15  8   8.9   4.9
 14500   2.8  37.0  335  15  8   9.3   5.1 |   2.4  36.3  320  16  8   9.7   5.3
 14000   4.2  39.6  335  15  8   9.3   5.1 |   3.9  39.0  325  16  8   9.9   5.4
 13500   5.6  42.1  330  14  7   9.4   5.1 |   5.3  41.5  325  17  9   9.9   5.4
 13000   7.0  44.6  330  14  7   9.4   5.2 |   6.8  44.2  325  17  9   9.9   5.4
 12500   8.4  47.1  325  13  7   9.4   5.1 |   8.3  46.9  325  18  9   9.8   5.4
 12000   9.8  49.6  325  13  6   9.3   5.1 |   9.7  49.5  330  18  9   9.6   5.2
 11500  11.1  52.0  320  12  6   9.3   5.1 |  11.2  52.2  330  19 10   9.4   5.2
 11000  12.6  54.7  320  13  6   9.1   5.0 |  12.5  54.5  330  19 10   8.9   4.9
 10500  14.0  57.2  315  13  7   5.7   3.1 |  13.9  57.0  330  18 10   5.2   2.9
 10250  14.2  57.6  315  14  7   6.4   3.5 |  14.1  57.4  330  18  9   6.2   3.4
 10000  15.0  59.0  310  14  7  11.5   6.3 |  14.9  58.8  325  18  9  11.7   6.4
  9750  15.8  60.4  310  15  8  10.4   5.7 |  15.7  60.3  325  18  9  10.7   5.9
  9500  16.6  61.9  310  16  8   9.6   5.2 |  16.4  61.5  325  18  9   9.2   5.1
  9250  17.2  63.0  305  17  9   7.5   4.1 |  17.0  62.6  320  17  9   8.0   4.4
  9000  17.8  64.0  300  16  8   8.0   4.4 |  17.7  63.9  320  16  8  10.3   5.6
  8750  18.4  65.1  295  16  8   8.4   4.6 |  18.5  65.3  315  15  8  11.0   6.1
  8500  19.0  66.2  290  16  8   8.6   4.7 |  19.2  66.6  315  14  7  10.3   5.6
  8250  19.7  67.5  285  15  8   9.4   5.2 |  20.0  68.0  315  14  7   9.4   5.2
  8000  20.3  68.5  280  14  7   8.4   4.6 |  20.7  69.3  315  14  7   9.7   5.3
  7750  20.9  69.6  275  14  7   7.4   4.0 |  21.4  70.5  315  14  7   9.9   5.4
  7500  21.4  70.5  265  14  7   7.6   4.2 |  22.1  71.8  315  14  7  10.0   5.5
  7250  22.0  71.6  265  14  7   7.4   4.1 |  22.9  73.2  315  13  7  10.2   5.6
  7000  22.6  72.7  265  13  7   7.7   4.2 |  23.7  74.7  315  13  7  10.2   5.6
  6750  23.1  73.6  260  13  7   8.0   4.4 |  24.4  75.9  315  13  7  10.7   5.8
  6500  23.6  74.5  260  13  7   4.1   2.2 |  25.2  77.4  315  13  7  10.8   5.9
  6250  23.6  74.5  255  11  6   2.2   1.2 |  26.1  79.0  310  13  7  11.4   6.3
  6000  23.7  74.7  250  10  5   0.8   0.4 |  26.9  80.4  310  12  6   9.5   5.2
  5750  23.6  74.5  240   8  4   2.1   1.2 |  27.6  81.7  310  12  6  13.1   7.2
  5500  24.0  75.2  225   7  4  14.0   7.7 |  29.0  84.2  310  12  6  26.3  14.4

           07/18/2014 at 1500 MDT          |       07/18/2014 at 1800 MDT
                                           |
K index... +23.4  LI... -1.0               | K index... +20.2  LI... -1.6
CAPE... +83.7  CIN... -38.1                | CAPE... +64.8  CIN... -39.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.2 -81.8  280  30 16   0.6   0.3 | -63.0 -81.4  285  33 17   0.4   0.2
 45000 -60.8 -77.4  285  46 24   3.9   2.2 | -60.8 -77.4  285  47 24   4.0   2.2
 40000 -54.2 -65.6  280  53 27   7.9   4.3 | -54.2 -65.6  285  53 27   7.4   4.1
 38000 -49.4 -56.9  285  53 27   8.0   4.4 | -49.6 -57.3  285  53 27   7.6   4.2
 36000 -44.6 -48.3  285  53 27   8.1   4.4 | -45.1 -49.2  285  54 28   7.6   4.2
 34000 -40.2 -40.4  285  49 25   7.2   3.9 | -40.6 -41.1  290  51 26   7.5   4.1
 32000 -35.3 -31.5  285  43 22   7.4   4.1 | -35.5 -31.9  290  47 24   7.7   4.2
 30000 -30.7 -23.3  285  39 20   7.9   4.3 | -30.9 -23.6  295  40 20   7.8   4.3
 29000 -28.3 -18.9  285  36 19   7.9   4.3 | -28.5 -19.3  295  36 19   7.8   4.3
 28000 -26.0 -14.8  285  34 18   7.2   3.9 | -26.2 -15.2  295  33 17   8.1   4.5
 27000 -24.0 -11.2  290  33 17   7.0   3.8 | -23.7 -10.7  300  30 16   8.2   4.5
 26000 -21.9  -7.4  290  32 16   7.0   3.9 | -21.2  -6.2  300  28 14   8.2   4.5
 25000 -19.8  -3.6  290  30 16   7.0   3.8 | -18.7  -1.7  300  26 13   7.9   4.4
 24000 -17.9  -0.2  290  28 14   6.6   3.6 | -16.8   1.8  300  25 13   6.5   3.6
 23000 -15.9   3.4  285  25 13   6.6   3.6 | -14.8   5.4  295  26 13   6.6   3.6
 22000 -14.0   6.8  280  23 12   6.8   3.7 | -12.9   8.8  295  26 13   6.3   3.5
 21000 -11.9  10.6  280  22 11   7.2   3.9 | -11.3  11.7  295  24 12   5.3   2.9
 20000  -9.8  14.4  280  21 11   7.2   4.0 |  -9.8  14.4  295  22 11   5.2   2.9
 19500  -8.7  16.3  280  21 11   7.2   3.9 |  -9.0  15.8  300  21 11   5.0   2.7
 19000  -7.6  18.3  280  20 11   7.6   4.2 |  -8.1  17.4  300  20 10   7.8   4.3
 18500  -6.5  20.3  280  20 10   7.6   4.2 |  -6.9  19.6  305  19 10   7.8   4.3
 18000  -5.3  22.5  280  19 10   7.5   4.1 |  -5.8  21.6  315  19 10   7.9   4.3
 17500  -4.3  24.3  285  19 10   7.2   4.0 |  -4.7  23.5  315  19 10   8.0   4.4
 17000  -3.2  26.2  285  19 10   7.2   4.0 |  -3.5  25.7  320  19 10   8.0   4.4
 16500  -2.1  28.2  290  18  9   7.3   4.0 |  -2.3  27.9  325  19 10   8.4   4.6
 16000  -0.5  31.1  295  18  9   7.3   4.0 |  -0.5  31.1  325  19 10   8.4   4.6
 15500   0.5  32.9  300  18  9   7.1   3.9 |   0.8  33.4  330  19 10   8.9   4.9
 15000   1.6  34.9  305  18  9   7.1   3.9 |   2.1  35.8  330  18  9   8.9   4.9
 14500   2.6  36.7  305  17  9   7.6   4.1 |   3.4  38.1  330  17  9   8.8   4.8
 14000   3.8  38.8  305  17  9   7.6   4.2 |   4.7  40.5  330  16  8   8.8   4.8
 13500   4.9  40.8  310  16  8   8.6   4.7 |   6.0  42.8  330  16  8   8.8   4.8
 13000   6.2  43.2  310  16  8   9.2   5.0 |   7.3  45.1  330  15  8   8.8   4.9
 12500   7.6  45.7  310  15  8   9.4   5.2 |   8.5  47.3  330  14  7   9.0   4.9
 12000   9.0  48.2  310  15  8   9.6   5.3 |   9.9  49.8  330  14  7   9.2   5.1
 11500  10.5  50.9  310  15  8   9.6   5.3 |  11.3  52.3  325  13  7   9.1   5.0
 11000  11.9  53.4  315  15  8   9.3   5.1 |  12.6  54.7  320  13  7   8.6   4.7
 10500  13.3  55.9  315  15  8   5.8   3.2 |  13.9  57.0  320  13  7   4.8   2.6
 10250  13.6  56.5  315  14  7   6.6   3.6 |  14.1  57.4  315  13  7   5.7   3.1
 10000  14.4  57.9  315  14  7  11.7   6.4 |  14.8  58.6  315  13  7  11.3   6.2
  9750  15.2  59.4  315  14  7  10.9   6.0 |  15.6  60.1  315  13  6  10.3   5.7
  9500  15.9  60.6  315  14  7   9.0   4.9 |  16.3  61.3  315  12  6   8.9   4.9
  9250  16.5  61.7  315  14  7   7.2   3.9 |  16.8  62.2  310  12  6   7.4   4.0
  9000  17.1  62.8  315  14  7   9.6   5.3 |  17.4  63.3  310  11  5   9.3   5.1
  8750  17.8  64.0  315  14  7  10.4   5.7 |  18.1  64.6  305  10  5   9.9   5.5
  8500  18.5  65.3  315  13  7   9.9   5.4 |  18.8  65.8  305   9  5   9.6   5.3
  8250  19.2  66.6  315  13  7   9.6   5.2 |  19.5  67.1  300   9  5   9.4   5.1
  8000  20.0  68.0  315  13  6   9.4   5.1 |  20.2  68.4  300   9  4   9.7   5.3
  7750  20.6  69.1  315  12  6   9.1   5.0 |  21.0  69.8  300   8  4  10.0   5.5
  7500  21.3  70.3  315  12  6   9.7   5.3 |  21.7  71.1  300   8  4  10.0   5.5
  7250  22.1  71.8  315  12  6  10.1   5.6 |  22.5  72.5  300   8  4  10.2   5.6
  7000  22.8  73.0  315  11  6  10.1   5.5 |  23.3  73.9  300   8  4   9.9   5.4
  6750  23.6  74.5  315  11  6  10.4   5.7 |  24.0  75.2  300   8  4   9.7   5.3
  6500  24.3  75.7  315  11  6  10.4   5.7 |  24.7  76.5  300   8  4  10.5   5.8
  6250  25.1  77.2  315  11  6  10.8   5.9 |  25.5  77.9  300   8  4  11.3   6.2
  6000  25.9  78.6  315  11  5   9.5   5.2 |  26.3  79.3  300   7  4  10.0   5.5
  5750  26.6  79.9  315  10  5  11.6   6.3 |  27.1  80.8  300   7  4  11.8   6.5
  5500  27.7  81.9  315  10  5  19.2  10.5 |  28.2  82.8  300   7  4  18.9  10.4
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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