Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241250
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0650 MDT Wednesday, September 24, 2014

This forecast is for Wednesday, September 24, 2014:

If the trigger temperature of 75.7 F/24.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 852 ft/min (4.3 m/s)
   Maximum height of thermals.................. 15047 ft MSL (9762 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 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................. 11673 ft MSL (6387 ft AGL)
Thermal soaring outlook for Thursday 09/25..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 14894 ft MSL (9609 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 17358 ft MSL (12073 ft AGL)
Wave soaring outlook for Thursday 09/25........ Poor

Remarks...

Sunrise/Sunset.................... 06:49:01 / 18:54:47 MDT
Total possible sunshine........... 12 hr 5 min 46 sec (725 min 46 sec)
Altitude of sun at 12:51:24 MDT... 49.59 degrees

Upper air data from rawinsonde observation taken on 09/24/2014 at 0600 MDT

Freezing level.................. 14355 ft MSL (9070 ft AGL)
Convective condensation level... 15783 ft MSL (10498 ft AGL)
Lifted condensation level....... 15492 ft MSL (10207 ft AGL)
Lifted index.................... -0.4
K index......................... +16.7

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  -64.5 -84.1   340   25   13   4.8   2.6   85.3 185.5    33.2      M    M
 45000  -59.9 -75.8   315   31   16   7.1   3.9   68.7 155.7    25.2      M    M
 40000  -51.1 -60.0   355   34   17   7.8   4.3   59.6 139.3    20.9      M    M
 38000  -47.9 -54.2   005   48   25   0.9   0.5   55.7 132.2    18.7      M    M
 36000  -48.0 -54.4   010   63   32   6.3   3.5   47.1 116.8    13.2      M    M
 34000  -42.7 -44.9   010   69   35   8.9   4.9   46.5 115.6    13.1      M    M
 32000  -36.7 -34.1   010   65   34   7.6   4.2   45.6 114.1    12.8      M    M
 30000  -32.9 -27.2   355   38   20   6.2   3.4   42.8 109.1    11.0      M    M
 29000  -30.7 -23.3   350   38   19   8.5   4.7   41.9 107.4    10.4      M    M
 28000  -28.1 -18.6   350   37   19   9.1   5.0   41.5 106.7    10.2      M    M
 27000  -25.3 -13.5   345   37   19   9.1   5.0   41.3 106.3    10.2      M    M
 26000  -23.1  -9.6   345   37   19   5.3   2.9   40.5 104.9     9.7      M    M
 25000  -21.7  -7.1   350   30   15   7.9   4.3   38.6 101.4     8.2      M    M
 24000  -19.2  -2.6   345   24   12   8.5   4.6   38.1 100.6     7.9      M    M
 23000  -16.6   2.1   350   16    8   8.6   4.7   37.7  99.8     7.6      M    M
 22000  -14.1   6.6   340   18    9   7.6   4.2   37.3  99.1     7.3      M    M
 21000  -12.1  10.2   335   20   10   6.7   3.7   36.1  97.0     6.4      M    M
 20000  -10.1  13.8   330   22   11   7.9   4.4   35.1  95.2     5.6      M    M
 19500   -8.7  16.3   335   19   10   9.1   5.0   35.0  95.0     5.5      M    M
 19000   -7.3  18.9   340   18    9   8.5   4.7   34.9  94.8     5.5      M    M
 18500   -6.4  20.5   345   19   10   4.2   2.3   34.2  93.6     4.9      M    M
 18000   -5.8  21.6   350   20   11   3.8   2.1   33.3  92.0     4.2      M    M
 17500   -5.0  23.0   350   22   11   7.8   4.3   32.6  90.7     3.4      M    M
 17000   -3.9  25.0   355   24   12   6.9   3.8   32.3  90.1     3.2      M    M
 16500   -3.1  26.4   350   22   11   4.3   2.4   31.5  88.6     2.5      M    M
 16000   -2.3  27.9   345   19   10   2.6   1.4   29.9  85.9     1.1      M    M
 15500   -1.5  29.3   345   17    9   7.9   4.3   29.3  84.7     0.5      M    M
 15000   -0.9  30.4   340   16    8   0.7   0.4   28.4  83.1    -0.4    846  4.3
 14500   -0.1  31.8   340   15    8   8.6   4.7   27.6  81.7    -1.1    808  4.1
 14000    1.1  34.0   335   14    7   7.2   4.0   27.3  81.1    -1.3    756  3.8
 13500    2.0  35.6   330   13    7   7.0   3.8   26.8  80.3    -1.9    714  3.6
 13000    3.0  37.4   325   13    7   8.1   4.4   26.4  79.5    -2.4    671  3.4
 12500    4.2  39.6   320   12    6   8.6   4.7   26.2  79.2    -2.6    619  3.1
 12000    5.5  41.9   315   12    6   8.6   4.7   26.0  78.9    -2.9    566  2.9
 11500    6.7  44.1   325   11    6   8.6   4.7   25.8  78.5    -3.1    514  2.6
 11000    8.0  46.4   335   10    5   8.6   4.7   25.7  78.2    -3.4    462  2.3
 10500    9.2  48.6   345   10    5   8.8   4.8   25.5  77.9    -3.6    410  2.1
 10250    9.8  49.6   350   10    5   9.0   5.0   25.4  77.8    -3.7    384  1.9
 10000   10.5  50.9   355    9    5   9.2   5.0   25.4  77.7    -3.8    356  1.8
  9750   11.2  52.2   360    9    5   9.3   5.1   25.3  77.6    -3.8    328  1.7
  9500   11.9  53.4   010    9    5   9.3   5.1   25.3  77.6    -3.8    300  1.5
  9250   12.6  54.7   015    9    5   9.3   5.1   25.3  77.5    -3.9    272  1.4
  9000   13.3  55.9   020    9    5   9.3   5.1   25.3  77.5    -3.9    244  1.2
  8750   14.0  57.2   015    9    4   9.3   5.1   25.2  77.4    -4.0    216  1.1
  8500   14.6  58.3   010    8    4   9.3   5.1   25.2  77.3    -4.0    188  1.0
  8250   15.3  59.5   360    8    4   9.2   5.1   25.1  77.3    -4.1    159  0.8
  8000   16.0  60.8   355    8    4   9.5   5.2   25.1  77.2    -4.1    131  0.7
  7750   16.7  62.1   350    7    3   8.5   4.7   25.1  77.1    -4.2    103  0.5
  7500   17.3  63.1   345    5    3   7.3   4.0   24.9  76.8    -4.4     79  0.4
  7250   17.8  64.0   335    4    2   7.6   4.1   24.7  76.5    -4.6     56  0.3
  7000   18.3  64.9   315    3    2   7.3   4.0   24.6  76.2    -4.8     33  0.2
  6750   18.9  66.0   320    3    2   8.0   4.4   24.4  75.9    -5.0      9  0.0
  6500   19.4  66.9   325    3    2   5.6   3.1   24.2  75.6    -5.2      M    M
  6250   19.5  67.1   325    4    2  -1.8  -1.0   23.6  74.6    -5.8      M    M
  6000   19.2  66.6   330    4    2  -4.4  -2.4   22.6  72.7    -6.9      M    M
  5750   18.6  65.5   330    3    1 -18.1  -9.9   21.2  70.2    -8.3      M    M
  5500   16.1  61.0   330    1    1 -46.5 -25.5   18.0  64.5   -11.5     56  0.3

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

           09/24/2014 at 0900 MDT          |       09/24/2014 at 1200 MDT
                                           |
K index... +21.6  LI... +0.4               | K index... +18.7  LI... +0.8
CAPE... 0.0  CIN... -0.2                   | 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 -64.6 -84.3  325  13  7   2.3   1.2 | -64.9 -84.8  330  15  8   2.8   1.5
 45000 -59.5 -75.1  340  28 14   5.6   3.1 | -59.8 -75.6  345  28 14   4.6   2.5
 40000 -51.3 -60.3  350  38 20   4.3   2.4 | -52.8 -63.0  360  39 20   5.9   3.2
 38000 -48.7 -55.7  005  44 23   4.3   2.3 | -49.2 -56.6  010  42 22   5.9   3.2
 36000 -46.1 -51.0  015  52 27   4.1   2.2 | -45.7 -50.3  020  47 24   5.8   3.2
 34000 -41.8 -43.2  015  51 26   7.9   4.3 | -41.3 -42.3  020  44 23   7.5   4.1
 32000 -36.5 -33.7  015  47 24   8.0   4.4 | -36.3 -33.3  020  39 20   7.6   4.2
 30000 -31.7 -25.1  010  43 22   8.0   4.4 | -31.4 -24.5  010  37 19   8.3   4.5
 29000 -29.3 -20.7  360  41 21   8.1   4.4 | -28.9 -20.0  005  37 19   8.3   4.5
 28000 -26.9 -16.4  355  39 20   7.6   4.2 | -26.5 -15.7  360  36 19   7.5   4.1
 27000 -24.7 -12.5  355  37 19   7.5   4.1 | -24.3 -11.7  005  35 18   7.4   4.1
 26000 -22.5  -8.5  355  36 18   7.5   4.1 | -22.1  -7.8  005  34 17   7.4   4.1
 25000 -20.2  -4.4  355  34 17   7.3   4.0 | -19.9  -3.8  005  33 17   7.3   4.0
 24000 -18.3  -0.9  355  30 15   6.5   3.6 | -17.8  -0.0  010  29 15   6.7   3.7
 23000 -16.3   2.7  355  26 13   6.5   3.6 | -15.8   3.6  010  25 13   6.8   3.7
 22000 -14.4   6.1  355  22 11   6.7   3.7 | -13.8   7.2  015  21 11   6.9   3.8
 21000 -12.3   9.9  355  19 10   7.1   3.9 | -11.7  10.9  010  19 10   7.1   3.9
 20000 -10.2  13.6  350  17  9   7.1   3.9 |  -9.6  14.7  005  16  8   7.2   3.9
 19500  -9.2  15.4  350  16  8   7.2   4.0 |  -8.6  16.5  005  15  8   7.2   4.0
 19000  -8.2  17.2  350  15  8   6.1   3.3 |  -7.6  18.3  360  14  7   6.4   3.5
 18500  -7.2  19.0  350  14  7   6.2   3.4 |  -6.6  20.1  360  13  6   6.4   3.5
 18000  -6.3  20.7  345  13  7   6.1   3.3 |  -5.6  21.9  355  11  6   5.9   3.2
 17500  -5.4  22.3  345  13  7   5.9   3.2 |  -4.8  23.4  350  10  5   5.4   3.0
 17000  -4.5  23.9  345  12  6   5.9   3.2 |  -4.0  24.8  350  10  5   5.3   2.9
 16500  -3.7  25.3  345  12  6   6.0   3.3 |  -3.2  26.2  345   9  5   6.1   3.3
 16000  -2.4  27.7  345  13  6   6.1   3.3 |  -1.9  28.6  340   8  4   6.1   3.3
 15500  -1.5  29.3  340  12  6   6.5   3.6 |  -1.0  30.2  340   8  4   6.3   3.4
 15000  -0.6  30.9  335  12  6   6.6   3.6 |  -0.1  31.8  335   8  4   6.3   3.4
 14500   0.2  32.4  335  12  6   6.4   3.5 |   0.8  33.4  335   7  4   6.9   3.8
 14000   1.1  34.0  330  10  5   6.4   3.5 |   1.8  35.2  330   6  3   6.9   3.8
 13500   2.0  35.6  325   9  5   7.4   4.0 |   2.7  36.9  320   6  3   7.2   4.0
 13000   3.1  37.6  325   9  4   7.6   4.2 |   3.7  38.7  315   5  3   7.3   4.0
 12500   4.2  39.6  320   8  4   8.3   4.5 |   4.8  40.6  305   4  2   8.3   4.5
 12000   5.4  41.7  315   7  4   8.6   4.7 |   6.0  42.8  300   4  2   8.7   4.8
 11500   6.7  44.1  310   7  4   8.6   4.7 |   7.3  45.1  295   4  2   8.6   4.7
 11000   7.9  46.2  305   7  3   8.5   4.7 |   8.5  47.3  285   4  2   8.4   4.6
 10500   9.1  48.4  295   6  3   3.9   2.2 |   9.7  49.5  280   4  2   3.9   2.2
 10250   9.3  48.7  295   6  3   4.0   2.2 |   9.9  49.8  275   4  2   6.0   3.3
 10000   9.9  49.8  280   5  2  10.0   5.5 |  10.7  51.3  260   4  2  12.5   6.8
  9750  10.6  51.1  255   4  2   9.6   5.3 |  11.6  52.9  245   5  2  11.2   6.1
  9500  11.3  52.3  230   5  2   7.1   3.9 |  12.3  54.1  235   6  3   7.8   4.3
  9250  11.7  53.1  220   5  3   5.1   2.8 |  12.8  55.0  230   6  3   5.6   3.0
  9000  12.2  54.0  210   6  3   9.0   4.9 |  13.3  55.9  220   7  3   8.6   4.7
  8750  13.0  55.4  205   7  4  10.9   6.0 |  14.0  57.2  210   7  4   9.6   5.2
  8500  13.7  56.7  200   8  4   8.8   4.8 |  14.7  58.5  205   7  4   8.4   4.6
  8250  14.4  57.9  200   8  4   7.8   4.3 |  15.2  59.4  200   7  4   8.0   4.4
  8000  15.0  59.0  195   8  4   9.8   5.4 |  15.8  60.4  195   7  4   8.7   4.8
  7750  15.8  60.4  195   8  4  10.3   5.6 |  16.5  61.7  190   7  3   9.7   5.3
  7500  16.5  61.7  190   8  4   8.1   4.5 |  17.2  63.0  190   6  3   9.8   5.4
  7250  17.1  62.8  190   8  4   7.8   4.3 |  17.9  64.2  190   6  3   9.8   5.4
  7000  17.7  63.9  190   8  4   8.5   4.7 |  18.7  65.7  185   6  3   9.8   5.4
  6750  18.2  64.8  185   7  4   5.3   2.9 |  19.4  66.9  185   6  3  10.2   5.6
  6500  18.4  65.1  190   7  3   1.7   0.9 |  20.2  68.4  185   6  3  10.5   5.8
  6250  18.6  65.5  195   6  3   4.3   2.4 |  21.0  69.8  180   5  3  10.3   5.7
  6000  18.8  65.8  205   6  3  -2.7  -1.5 |  21.8  71.2  180   5  3  10.8   5.9
  5750  18.1  64.6  205   5  3  -8.1  -4.5 |  22.7  72.9  180   5  3  14.9   8.2
  5500  17.8  64.0  210   4  2   3.1   1.7 |  24.0  75.2  180   5  2  20.4  11.2

           09/24/2014 at 1500 MDT          |       09/24/2014 at 1800 MDT
                                           |
K index... +16.3  LI... +0.4               | K index... +23.3  LI... +0.1
CAPE... 0.0  CIN... -1.2                   | CAPE... +0.9  CIN... -2.0
                                           |
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 -65.5 -85.9  335  15  8   3.0   1.6 | -65.4 -85.7  335  18  9   2.7   1.5
 45000 -60.1 -76.2  355  26 13   4.8   2.6 | -60.3 -76.5  350  26 14   4.9   2.7
 40000 -52.8 -63.0  005  34 18   5.9   3.2 | -52.8 -63.0  010  31 16   5.9   3.2
 38000 -49.2 -56.6  020  38 20   5.9   3.2 | -49.3 -56.7  025  33 17   5.9   3.2
 36000 -45.7 -50.3  025  43 22   5.7   3.1 | -45.7 -50.3  035  37 19   5.6   3.1
 34000 -41.2 -42.2  025  41 21   7.8   4.3 | -41.0 -41.8  035  36 19   8.2   4.5
 32000 -36.0 -32.8  020  36 19   7.9   4.3 | -35.4 -31.7  030  34 18   8.2   4.5
 30000 -31.2 -24.2  020  36 18   7.9   4.3 | -30.8 -23.4  025  33 17   7.7   4.2
 29000 -28.8 -19.8  020  36 18   7.9   4.4 | -28.5 -19.3  025  32 16   7.7   4.2
 28000 -26.5 -15.7  015  35 18   7.9   4.3 | -26.2 -15.2  020  31 16   8.2   4.5
 27000 -24.1 -11.4  015  35 18   7.9   4.4 | -23.7 -10.7  020  30 15   8.2   4.5
 26000 -21.7  -7.1  015  34 18   8.0   4.4 | -21.3  -6.3  020  29 15   8.2   4.5
 25000 -19.4  -2.9  015  34 17   7.7   4.2 | -18.8  -1.8  020  28 14   7.9   4.4
 24000 -17.2   1.0  015  30 15   7.3   4.0 | -16.6   2.1  020  26 13   7.5   4.1
 23000 -15.0   5.0  015  26 13   7.3   4.0 | -14.4   6.1  020  23 12   7.6   4.2
 22000 -12.9   8.8  020  21 11   6.8   3.7 | -12.1  10.2  020  21 11   6.5   3.6
 21000 -11.0  12.2  010  18  9   6.3   3.5 | -10.5  13.1  010  18  9   5.5   3.0
 20000  -9.2  15.4  360  15  7   6.3   3.5 |  -8.9  16.0  350  15  8   5.5   3.0
 19500  -8.2  17.2  355  13  7   6.4   3.5 |  -8.1  17.4  340  15  8   5.5   3.0
 19000  -7.3  18.9  345  12  6   6.5   3.6 |  -7.3  18.9  335  15  8   5.5   3.0
 18500  -6.4  20.5  340  12  6   6.5   3.6 |  -6.5  20.3  330  15  8   5.6   3.1
 18000  -5.4  22.3  335  12  6   6.1   3.3 |  -5.8  21.6  325  16  8   6.1   3.4
 17500  -4.6  23.7  330  11  6   5.8   3.2 |  -4.8  23.4  320  16  8   6.5   3.6
 17000  -3.7  25.3  325  11  6   5.8   3.2 |  -3.9  25.0  320  16  8   6.6   3.6
 16500  -2.8  27.0  320  11  6   6.3   3.5 |  -2.8  27.0  320  16  8   8.6   4.7
 16000  -1.4  29.5  315  10  5   6.5   3.6 |  -1.0  30.2  315  15  8   8.3   4.6
 15500  -0.3  31.5  315  10  5   7.3   4.0 |   0.2  32.4  310  14  7   8.0   4.4
 15000   0.7  33.3  310   9  5   7.1   3.9 |   1.3  34.3  310  13  7   8.2   4.5
 14500   1.9  35.4  305   9  4   8.3   4.6 |   2.4  36.3  305  12  6   6.9   3.8
 14000   3.0  37.4  305   8  4   8.2   4.5 |   3.5  38.3  305  10  5   7.0   3.9
 13500   4.2  39.6  300   7  4   7.9   4.3 |   4.6  40.3  300   7  4   7.3   4.0
 13000   5.4  41.7  295   6  3   7.9   4.3 |   5.7  42.3  290   5  3   7.3   4.0
 12500   6.5  43.7  295   5  3   7.7   4.2 |   6.8  44.2  260   3  2   7.6   4.1
 12000   7.6  45.7  280   3  2   7.7   4.2 |   8.0  46.4  200   3  1   7.7   4.2
 11500   8.7  47.7  260   2  1   8.1   4.5 |   9.2  48.6  165   5  2   8.3   4.5
 11000   9.9  49.8  220   2  1   8.3   4.6 |  10.4  50.7  155   5  3   8.5   4.7
 10500  11.0  51.8  185   2  1   3.2   1.7 |  11.6  52.9  150   6  3   3.8   2.1
 10250  11.2  52.2  185   2  1   6.1   3.3 |  11.8  53.2  150   6  3   6.2   3.4
 10000  12.0  53.6  175   3  1  12.9   7.1 |  12.6  54.7  140   6  3  12.7   7.0
  9750  12.8  55.0  165   3  2  10.9   6.0 |  13.4  56.1  135   6  3  11.1   6.1
  9500  13.5  56.3  160   3  2   8.5   4.6 |  14.1  57.4  125   6  3   9.2   5.1
  9250  14.0  57.2  160   3  2   7.0   3.8 |  14.7  58.5  125   5  3   7.9   4.3
  9000  14.7  58.5  160   3  2  10.0   5.5 |  15.4  59.7  125   5  3  10.2   5.6
  8750  15.4  59.7  155   3  2  10.8   5.9 |  16.2  61.2  125   5  3  10.6   5.8
  8500  16.2  61.2  155   3  2   9.7   5.3 |  16.9  62.4  120   5  3   9.5   5.2
  8250  16.8  62.2  155   3  2   9.1   5.0 |  17.5  63.5  120   5  3   8.8   4.8
  8000  17.5  63.5  155   3  2  10.3   5.6 |  18.2  64.8  115   5  3  10.1   5.6
  7750  18.3  64.9  155   3  2  10.9   6.0 |  19.0  66.2  115   5  2  10.9   6.0
  7500  19.1  66.4  155   3  2  10.0   5.5 |  19.8  67.6  115   5  2   9.7   5.3
  7250  19.8  67.6  155   3  2   9.9   5.4 |  20.5  68.9  110   4  2   9.9   5.4
  7000  20.6  69.1  155   3  2  10.3   5.6 |  21.2  70.2  110   4  2   8.9   4.9
  6750  21.4  70.5  150   3  2  10.4   5.7 |  21.9  71.4  105   4  2   9.0   4.9
  6500  22.1  71.8  150   3  2  10.1   5.5 |  22.6  72.7  105   4  2  10.1   5.5
  6250  22.9  73.2  150   3  2  10.0   5.5 |  23.3  73.9  100   4  2   9.6   5.2
  6000  23.6  74.5  150   3  1  10.7   5.9 |  24.1  75.4  100   4  2  10.6   5.8
  5750  24.6  76.3  155   3  1  14.8   8.1 |  24.8  76.6  095   3  2  10.2   5.6
  5500  25.8  78.4  155   3  1  19.2  10.5 |  25.4  77.7  095   3  2   7.0   3.9
________________________________________________________________________________

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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