Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170100
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1900 MDT Tuesday, September 16, 2014

This forecast is for Wednesday, September 17, 2014:

If the trigger temperature of 82.7 F/28.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1281 ft/min (6.5 m/s)
   Maximum height of thermals.................. 18523 ft MSL (13236 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10263 ft MSL (4976 ft AGL)
Thermal soaring outlook for Thursday 09/18..... 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)................ Neither
Potential height of wave....................... 21295 ft MSL (16008 ft AGL)
Wave soaring outlook for Thursday 09/18........ Poor

Remarks... None

Sunrise/Sunset.................... 06:42:25 / 19:06:16 MDT
Total possible sunshine........... 12 hr 23 min 52 sec (743 min 52 sec)
Altitude of sun at 12:53:51 MDT... 52.30 degrees

Upper air data from numerical model forecast valid on 09/17/2014 at 0600 MDT

Freezing level.................. 15502 ft MSL (10215 ft AGL)
Convective condensation level... 16748 ft MSL (11461 ft AGL)
Lifted condensation level....... 17118 ft MSL (11830 ft AGL)
Lifted index.................... -1.9
K index......................... +15.8

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  -67.3 -89.1   300   54   28   1.6   0.9      M     M       M      M    M
 45000  -62.6 -80.7   290   71   36   6.8   3.7      M     M       M      M    M
 40000  -52.3 -62.1   285   66   34   6.6   3.6      M     M       M      M    M
 38000  -48.3 -54.9   285   59   30   6.6   3.6      M     M       M      M    M
 36000  -44.3 -47.7   285   52   27   6.7   3.6      M     M       M      M    M
 34000  -40.6 -41.1   285   46   24   6.1   3.3      M     M       M      M    M
 32000  -36.5 -33.7   285   41   21   5.9   3.3      M     M       M      M    M
 30000  -32.2 -26.0   290   32   17   7.5   4.1   43.1 109.6     8.7      M    M
 29000  -30.0 -22.0   290   27   14   7.5   4.1   42.3 108.1     8.2      M    M
 28000  -27.7 -17.9   290   23   12   7.6   4.2   41.6 106.8     7.7      M    M
 27000  -25.4 -13.7   290   22   11   7.7   4.2   40.6 105.2     7.0      M    M
 26000  -23.1  -9.6   290   20   10   7.7   4.2   39.9 103.7     6.5      M    M
 25000  -20.8  -5.4   290   19   10   7.7   4.2   39.2 102.6     6.0      M    M
 24000  -18.7  -1.7   295   18    9   7.1   3.9   38.2 100.8     5.2      M    M
 23000  -16.6   2.1   295   17    9   7.1   3.9   37.2  99.0     4.5      M    M
 22000  -14.5   5.9   300   17    9   6.9   3.8   36.4  97.5     3.8      M    M
 21000  -12.7   9.1   305   15    8   5.8   3.2   35.0  94.9     2.6      M    M
 20000  -11.0  12.2   310   14    7   5.8   3.2   33.6  92.4     1.4      M    M
 19500  -10.2  13.6   315   13    7   5.7   3.1   32.9  91.3     0.8      M    M
 19000   -9.2  15.4   320   13    7   8.0   4.4   32.4  90.3     0.3      M    M
 18500   -8.0  17.6   320   12    6   8.1   4.4   32.1  89.8     0.0      M    M
 18000   -6.8  19.8   325   12    6   8.3   4.5   31.8  89.3    -0.2   1237  6.3
 17500   -5.6  21.9   325   11    6   8.7   4.8   31.6  88.9    -0.4   1184  6.0
 17000   -4.3  24.3   330   11    6   8.7   4.8   31.5  88.6    -0.6   1131  5.7
 16500   -3.0  26.6   335   11    6   8.8   4.8   31.3  88.3    -0.8   1077  5.5
 16000   -1.7  28.9   335   11    6   8.8   4.8   31.1  88.0    -0.9   1023  5.2
 15500    0.3  32.5   335   10    5   9.3   5.1   30.9  87.6    -1.1    941  4.8
 15000    1.7  35.1   335    9    5   9.2   5.1   30.8  87.5    -1.2    885  4.5
 14500    3.1  37.6   335    9    5   9.2   5.1   30.7  87.3    -1.3    828  4.2
 14000    4.5  40.1   335    8    4   9.2   5.1   30.6  87.2    -1.4    772  3.9
 13500    5.9  42.6   335    8    4   9.0   5.0   30.6  87.0    -1.5    716  3.6
 13000    7.2  45.0   335    8    4   8.9   4.9   30.4  86.8    -1.6    661  3.4
 12500    8.5  47.3   335    8    4   8.9   4.9   30.3  86.5    -1.7    606  3.1
 12000    9.8  49.6   330    8    4   8.9   4.9   30.2  86.3    -1.9    552  2.8
 11500   11.1  52.0   320    7    4   8.7   4.8   30.0  86.1    -2.1    498  2.5
 11000   12.4  54.3   315    7    4   8.1   4.4   29.8  85.7    -2.3    447  2.3
 10500   13.6  56.5   310    7    4   4.9   2.7   29.6  85.3    -2.6    396  2.0
 10250   13.8  56.8   305    7    4   5.9   3.2   29.1  84.4    -3.1    382  1.9
 10000   14.5  58.1   305    7    4  10.9   6.0   29.1  84.4    -3.1    353  1.8
  9750   15.2  59.4   300    8    4   9.9   5.4   29.1  84.4    -3.2    325  1.6
  9500   15.9  60.6   295    8    4   8.8   4.8   29.1  84.4    -3.2    296  1.5
  9250   16.4  61.5   290    8    4   6.9   3.8   28.9  84.1    -3.4    273  1.4
  9000   17.0  62.6   290    8    4   8.4   4.6   28.8  83.8    -3.6    250  1.3
  8750   17.6  63.7   285    8    4   9.5   5.2   28.7  83.7    -3.7    223  1.1
  8500   18.3  64.9   280    8    4   8.7   4.8   28.7  83.6    -3.8    196  1.0
  8250   18.9  66.0   280    8    4   8.0   4.4   28.6  83.4    -3.9    171  0.9
  8000   19.4  66.9   275    8    4   8.1   4.5   28.4  83.2    -4.1    147  0.7
  7750   20.0  68.0   270    8    4   8.6   4.7   28.3  83.0    -4.3    121  0.6
  7500   20.6  69.1   265    9    4   7.6   4.2   28.2  82.8    -4.4     96  0.5
  7250   21.1  70.0   260    9    4   6.5   3.6   28.0  82.4    -4.7     74  0.4
  7000   21.6  70.9   260    9    4   7.2   4.0   27.8  82.0    -4.9     51  0.3
  6750   22.1  71.8   255    9    4   4.5   2.5   27.5  81.5    -5.2     30  0.2
  6500   22.1  71.8   250    9    4  -4.9  -2.7   26.8  80.2    -5.9     22  0.1
  6250   21.4  70.5   250    8    4 -12.6  -6.9   25.3  77.6    -7.4     37  0.2
  6000   20.6  69.1   250    8    4  -2.0  -1.1   23.9  75.0    -8.9     51  0.3
  5750   20.5  68.9   260    8    4 -15.5  -8.5   23.0  73.3    -9.8     49  0.2
  5500   17.1  62.8   245    7    3 -69.6 -38.2   19.1  66.4   -13.8    141  0.7

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

           09/17/2014 at 0900 MDT          |       09/17/2014 at 1200 MDT
                                           |
K index... +16.2  LI... +0.7               | K index... +16.9  LI... -0.7
CAPE... 0.0  CIN... -1.0                   | CAPE... +33.2  CIN... -66.6
                                           |
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 -67.4 -89.3  295  48 25   2.1   1.2 | -66.9 -88.4  290  44 23   2.7   1.5
 45000 -62.0 -79.6  290  68 35   7.0   3.8 | -61.3 -78.3  285  61 31   6.3   3.5
 40000 -51.6 -60.9  285  73 38   6.1   3.4 | -51.8 -61.2  280  70 36   6.3   3.4
 38000 -47.9 -54.2  280  63 32   6.1   3.4 | -48.1 -54.6  275  61 32   6.3   3.4
 36000 -44.2 -47.6  280  52 27   6.1   3.4 | -44.3 -47.7  275  53 27   6.3   3.4
 34000 -40.7 -41.3  285  45 23   5.8   3.2 | -40.2 -40.4  280  45 23   6.0   3.3
 32000 -36.8 -34.2  290  39 20   5.7   3.1 | -36.6 -33.9  290  38 20   5.9   3.3
 30000 -32.7 -26.9  290  31 16   7.1   3.9 | -32.6 -26.7  295  30 16   6.8   3.7
 29000 -30.6 -23.1  295  26 13   7.1   3.9 | -30.6 -23.1  295  27 14   6.8   3.8
 28000 -28.4 -19.1  295  22 11   7.6   4.2 | -28.5 -19.3  300  23 12   7.6   4.1
 27000 -26.0 -14.8  295  21 11   8.0   4.4 | -26.1 -15.0  300  22 12   8.2   4.5
 26000 -23.6 -10.5  295  20 10   8.0   4.4 | -23.6 -10.5  300  22 11   8.2   4.5
 25000 -21.2  -6.2  295  20 10   8.0   4.4 | -21.2  -6.2  300  21 11   8.2   4.5
 24000 -19.0  -2.2  295  19 10   7.1   3.9 | -19.0  -2.2  300  20 10   7.2   4.0
 23000 -16.9   1.6  295  18  9   7.1   3.9 | -16.8   1.8  300  18  9   7.2   4.0
 22000 -14.8   5.4  295  17  9   7.0   3.8 | -14.6   5.7  295  16  8   7.1   3.9
 21000 -13.0   8.6  295  16  8   6.1   3.4 | -12.7   9.1  295  16  8   6.1   3.4
 20000 -11.2  11.8  295  15  8   6.2   3.4 | -10.9  12.4  295  15  8   6.2   3.4
 19500 -10.3  13.5  295  14  7   6.1   3.4 | -10.0  14.0  295  15  8   6.1   3.3
 19000  -9.4  15.1  300  14  7   7.5   4.1 |  -9.1  15.6  295  15  8   7.5   4.1
 18500  -8.3  17.1  300  13  7   7.6   4.2 |  -8.0  17.6  295  14  7   7.6   4.2
 18000  -7.2  19.0  305  12  6   8.1   4.4 |  -6.9  19.6  295  14  7   7.9   4.3
 17500  -5.9  21.4  305  11  6   9.0   4.9 |  -5.7  21.7  290  12  6   8.4   4.6
 17000  -4.6  23.7  310  10  5   9.0   4.9 |  -4.5  23.9  290  11  6   8.4   4.6
 16500  -3.2  26.2  310   9  5   9.2   5.1 |  -2.5  27.5  290   9  5   9.1   5.0
 16000  -1.1  30.0  310   7  4   9.2   5.1 |  -1.1  30.0  290   8  4   9.2   5.0
 15500   0.2  32.4  315   7  3   8.6   4.7 |   0.2  32.4  285   7  4   8.6   4.7
 15000   1.5  34.7  315   6  3   8.7   4.7 |   1.5  34.7  285   6  3   8.6   4.7
 14500   2.8  37.0  320   5  3   8.9   4.9 |   2.7  36.9  285   5  3   8.8   4.8
 14000   4.1  39.4  325   5  2   9.0   4.9 |   4.0  39.2  290   4  2   8.8   4.8
 13500   5.5  41.9  335   4  2   8.9   4.9 |   5.3  41.5  295   3  2   8.8   4.8
 13000   6.8  44.2  345   4  2   8.8   4.9 |   6.6  43.9  305   3  2   8.8   4.8
 12500   8.1  46.6  355   5  2   9.0   4.9 |   7.9  46.2  325   3  2   8.9   4.9
 12000   9.4  48.9  360   5  3   9.1   5.0 |   9.2  48.6  330   3  2   9.0   5.0
 11500  10.8  51.4  360   5  3   9.0   4.9 |  10.6  51.1  340   3  2   9.0   4.9
 11000  12.1  53.8  360   6  3   8.5   4.7 |  11.9  53.4  350   4  2   8.7   4.8
 10500  13.5  56.3  355   6  3   5.0   2.7 |  13.2  55.8  355   4  2   5.6   3.1
 10250  13.7  56.7  355   7  3   6.0   3.3 |  13.5  56.3  355   5  2   6.6   3.6
 10000  14.5  58.1  355   7  4  11.4   6.2 |  14.3  57.7  355   5  3  11.4   6.3
  9750  15.2  59.4  350   7  4  10.3   5.6 |  15.1  59.2  355   5  3  10.5   5.8
  9500  16.0  60.8  345   8  4   9.2   5.0 |  15.8  60.4  355   5  3   9.3   5.1
  9250  16.6  61.9  345   8  4   7.4   4.1 |  16.4  61.5  355   6  3   7.6   4.2
  9000  17.2  63.0  340   8  4   8.6   4.7 |  17.0  62.6  355   6  3   8.7   4.8
  8750  17.9  64.2  340   9  4   9.5   5.2 |  17.7  63.9  355   6  3   9.2   5.1
  8500  18.6  65.5  335   9  5   8.5   4.7 |  18.4  65.1  355   7  3   8.7   4.8
  8250  19.2  66.6  335   9  5   7.6   4.2 |  19.0  66.2  355   7  4   8.2   4.5
  8000  19.8  67.6  330  10  5   7.5   4.1 |  19.6  67.3  355   7  4   8.4   4.6
  7750  20.3  68.5  330  10  5   7.3   4.0 |  20.3  68.5  355   8  4   8.4   4.6
  7500  20.8  69.4  325  10  5   7.2   3.9 |  20.9  69.6  350   8  4   9.0   4.9
  7250  21.3  70.3  325  10  5   6.9   3.8 |  21.5  70.7  350   7  4   9.6   5.2
  7000  21.8  71.2  320   9  5   7.3   4.0 |  22.2  72.0  350   6  3   9.4   5.1
  6750  22.3  72.1  320   9  5   4.8   2.7 |  22.9  73.2  345   5  3   9.7   5.3
  6500  22.4  72.3  315   9  5  -1.0  -0.6 |  23.6  74.5  345   5  3  10.3   5.6
  6250  22.0  71.6  310   9  4  -4.4  -2.4 |  24.4  75.9  345   5  2  11.2   6.1
  6000  21.7  71.1  305   8  4   0.4   0.2 |  25.2  77.4  345   5  2   9.0   4.9
  5750  21.7  71.1  300   9  5  -4.5  -2.5 |  25.9  78.6  345   4  2  12.1   6.6
  5500  20.4  68.7  280   6  3 -25.1 -13.8 |  27.2  81.0  345   4  2  24.2  13.3

           09/17/2014 at 1500 MDT          |       09/17/2014 at 1800 MDT
                                           |
K index... +15.1  LI... -0.6               | K index... +21.4  LI... -0.5
CAPE... +86.7  CIN... -37.2                | CAPE... +81.9  CIN... -72.1
                                           |
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 -66.9 -88.4  285  47 24   2.8   1.5 | -66.2 -87.2  290  48 25   2.4   1.3
 45000 -61.3 -78.3  285  57 29   6.0   3.3 | -61.3 -78.3  290  55 28   5.3   2.9
 40000 -52.3 -62.1  285  55 29   6.2   3.4 | -53.2 -63.8  290  53 27   6.6   3.6
 38000 -48.6 -55.5  280  52 27   6.2   3.4 | -49.2 -56.6  295  49 25   6.5   3.6
 36000 -44.9 -48.8  280  49 25   6.2   3.4 | -45.3 -49.5  295  45 23   6.5   3.6
 34000 -40.6 -41.1  285  42 22   6.3   3.4 | -40.9 -41.6  300  39 20   6.5   3.6
 32000 -36.9 -34.4  295  35 18   6.2   3.4 | -37.0 -34.6  305  34 17   6.4   3.5
 30000 -32.8 -27.0  300  30 15   6.9   3.8 | -32.6 -26.7  310  30 15   7.6   4.1
 29000 -30.7 -23.3  300  27 14   6.9   3.8 | -30.3 -22.5  315  27 14   7.6   4.2
 28000 -28.6 -19.5  305  25 13   7.5   4.1 | -28.1 -18.6  315  25 13   7.5   4.1
 27000 -26.2 -15.2  305  24 13   8.0   4.4 | -25.9 -14.6  320  24 12   7.4   4.1
 26000 -23.9 -11.0  310  24 12   8.0   4.4 | -23.6 -10.5  320  22 12   7.5   4.1
 25000 -21.5  -6.7  310  23 12   8.0   4.4 | -21.4  -6.5  325  21 11   7.5   4.1
 24000 -19.1  -2.4  310  22 11   7.9   4.3 | -19.1  -2.4  320  20 10   7.8   4.3
 23000 -16.7   1.9  310  21 11   7.9   4.3 | -16.8   1.8  320  20 10   7.8   4.3
 22000 -14.4   6.1  310  19 10   7.7   4.2 | -14.4   6.1  320  19 10   7.6   4.2
 21000 -12.4   9.7  310  18  9   6.4   3.5 | -12.4   9.7  320  18 10   6.8   3.7
 20000 -10.5  13.1  305  18  9   6.4   3.5 | -10.4  13.3  315  18  9   6.8   3.8
 19500  -9.6  14.7  305  18  9   6.2   3.4 |  -9.4  15.1  315  17  9   6.7   3.7
 19000  -8.5  16.7  305  18  9   8.2   4.5 |  -8.3  17.1  315  17  9   8.6   4.7
 18500  -7.3  18.9  305  18  9   8.3   4.5 |  -7.0  19.4  315  16  8   8.8   4.8
 18000  -6.1  21.0  305  18  9   8.4   4.6 |  -5.6  21.9  310  16  8   8.7   4.8
 17500  -4.8  23.4  305  17  9   8.8   4.8 |  -4.4  24.1  310  15  8   8.5   4.7
 17000  -3.5  25.7  305  16  8   8.9   4.9 |  -3.2  26.2  315  14  7   8.6   4.7
 16500  -1.6  29.1  305  14  7   8.6   4.7 |  -1.4  29.5  320  12  6   8.4   4.6
 16000  -0.3  31.5  305  12  6   8.6   4.7 |  -0.2  31.6  325  12  6   8.4   4.6
 15500   0.9  33.6  305  11  6   8.4   4.6 |   1.1  34.0  330  11  6   8.4   4.6
 15000   2.1  35.8  300   9  5   8.5   4.6 |   2.3  36.1  335  10  5   8.4   4.6
 14500   3.4  38.1  300   8  4   8.0   4.4 |   3.5  38.3  340   9  5   8.6   4.7
 14000   4.5  40.1  300   6  3   7.9   4.3 |   4.9  40.8  340   7  4   8.6   4.7
 13500   5.7  42.3  300   4  2   8.3   4.6 |   6.2  43.2  345   6  3   8.2   4.5
 13000   6.9  44.4  310   3  2   8.6   4.7 |   7.3  45.1  005   3  2   7.9   4.3
 12500   8.2  46.8  335   2  1   8.8   4.8 |   8.5  47.3  055   2  1   8.1   4.4
 12000   9.5  49.1  360   2  1   8.9   4.9 |   9.8  49.6  085   2  1   8.6   4.7
 11500  10.8  51.4  025   2  1   9.0   4.9 |  11.0  51.8  100   3  2   8.7   4.8
 11000  12.1  53.8  030   3  1   8.9   4.9 |  12.3  54.1  105   3  2   8.9   4.9
 10500  13.4  56.1  030   3  2   5.5   3.0 |  13.6  56.5  105   3  2   6.2   3.4
 10250  13.7  56.7  030   3  2   6.7   3.7 |  14.0  57.2  100   3  2   7.4   4.1
 10000  14.5  58.1  030   3  2  12.0   6.6 |  14.8  58.6  100   3  2  11.9   6.5
  9750  15.3  59.5  030   3  2  11.0   6.0 |  15.6  60.1  095   3  2  11.0   6.0
  9500  16.1  61.0  025   3  2   9.9   5.4 |  16.4  61.5  090   3  2  10.2   5.6
  9250  16.7  62.1  025   3  2   8.5   4.7 |  17.1  62.8  085   3  1   8.7   4.8
  9000  17.4  63.3  025   3  2  10.0   5.5 |  17.7  63.9  085   3  1   9.4   5.2
  8750  18.2  64.8  020   3  2  10.6   5.8 |  18.5  65.3  080   2  1   9.9   5.4
  8500  19.0  66.2  020   3  2  10.3   5.7 |  19.2  66.6  080   2  1   9.7   5.3
  8250  19.7  67.5  020   3  2  10.3   5.6 |  19.9  67.8  070   2  1   9.6   5.3
  8000  20.5  68.9  020   3  2  10.0   5.5 |  20.6  69.1  060   2  1   9.6   5.3
  7750  21.2  70.2  015   3  2   9.6   5.3 |  21.3  70.3  050   2  1   9.7   5.3
  7500  21.9  71.4  015   3  2   9.9   5.4 |  22.0  71.6  040   1  1   9.6   5.3
  7250  22.7  72.9  015   3  2   9.9   5.4 |  22.8  73.0  025   1  1   9.5   5.2
  7000  23.4  74.1  015   3  2  10.1   5.5 |  23.5  74.3  010   1  1   9.6   5.3
  6750  24.2  75.6  015   3  2  10.5   5.8 |  24.2  75.6  360   1  1   9.9   5.4
  6500  25.0  77.0  015   3  2  10.4   5.7 |  24.9  76.8  350   1  1  10.2   5.6
  6250  25.7  78.3  010   3  2  10.6   5.8 |  25.7  78.3  345   2  1  10.4   5.7
  6000  26.5  79.7  010   3  2   9.4   5.1 |  26.4  79.5  340   2  1  10.0   5.5
  5750  27.3  81.1  010   3  2  12.3   6.8 |  27.1  80.8  335   2  1   8.8   4.8
  5500  28.5  83.3  010   3  2  21.9  12.0 |  27.7  81.9  335   2  1   8.2   4.5
________________________________________________________________________________

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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