Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 020125
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1925 MDT Wednesday, October 1, 2014

This forecast is for Thursday, October 2, 2014:

If the trigger temperature of 51.7 F/10.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 999 ft/min (5.1 m/s)
   Maximum height of thermals.................. 17317 ft MSL (12030 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 0930 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................. 13116 ft MSL (7829 ft AGL)
Thermal soaring outlook for Friday 10/03....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14391 ft MSL (9104 ft AGL)
Wave soaring outlook for Friday 10/03.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:56:44 / 18:41:46 MDT
Total possible sunshine........... 11 hr 45 min 3 sec (705 min 3 sec)
Altitude of sun at 12:48:46 MDT... 46.48 degrees

Upper air data from numerical model forecast valid on 10/02/2014 at 0600 MDT

Freezing level.................. 8654 ft MSL (3367 ft AGL)
Convective condensation level... 9449 ft MSL (4162 ft AGL)
Lifted condensation level....... 12809 ft MSL (7521 ft AGL)
Lifted index.................... -2.9
K index......................... +18.2

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  -57.3 -71.1   260   30   15   1.9   1.0      M     M       M      M    M
 45000  -54.2 -65.6   255   37   19   2.4   1.3      M     M       M      M    M
 40000  -50.6 -59.1   290   25   13   2.4   1.3      M     M       M      M    M
 38000  -49.3 -56.7   300   25   13   1.8   1.0      M     M       M      M    M
 36000  -48.2 -54.8   310   25   13   1.8   1.0      M     M       M      M    M
 34000  -46.9 -52.4   320   26   13   3.4   1.8      M     M       M      M    M
 32000  -45.0 -49.0   320   24   13   3.3   1.8      M     M       M      M    M
 30000  -42.3 -44.1   320   22   11   5.9   3.2   34.1  93.4    11.0      M    M
 29000  -40.5 -40.9   315   20   10   5.9   3.2   32.5  90.5    10.0      M    M
 28000  -38.7 -37.7   310   19   10   5.9   3.2   31.0  87.9     9.0      M    M
 27000  -36.9 -34.4   300   17    9   7.0   3.8   29.7  85.5     8.0      M    M
 26000  -34.7 -30.5   295   16    8   7.5   4.1   28.8  83.8     7.4      M    M
 25000  -32.4 -26.3   285   15    8   7.5   4.1   27.9  82.2     6.8      M    M
 24000  -30.2 -22.4   275   14    7   7.5   4.1   27.2  81.0     6.3      M    M
 23000  -27.9 -18.2   280   12    6   7.6   4.2   26.3  79.4     5.6      M    M
 22000  -25.6 -14.1   280   11    6   7.6   4.2   25.5  78.0     5.0      M    M
 21000  -23.4 -10.1   290   10    5   5.9   3.2   24.8  76.6     4.4      M    M
 20000  -21.9  -7.4   315   12    6   5.5   3.0   23.1  73.7     3.1      M    M
 19500  -21.1  -6.0   325   14    7   5.5   3.0   22.4  72.3     2.4      M    M
 19000  -20.3  -4.5   335   17    9   5.6   3.1   21.7  71.0     1.8      M    M
 18500  -19.4  -2.9   340   19   10   6.3   3.4   21.0  69.8     1.2      M    M
 18000  -18.4  -1.1   340   19   10   6.7   3.7   20.5  68.9     0.7      M    M
 17500  -17.5   0.5   340   19   10   6.7   3.7   20.0  68.0     0.3      M    M
 17000  -16.5   2.3   340   19   10   6.8   3.7   19.5  67.0    -0.2    979  5.0
 16500  -15.5   4.1   335   19   10   6.7   3.7   18.9  66.1    -0.7    934  4.7
 16000  -14.4   6.1   335   19   10   8.2   4.5   18.5  65.4    -1.0    887  4.5
 15500  -13.1   8.4   330   19   10   8.3   4.6   18.3  64.9    -1.3    835  4.2
 15000  -11.3  11.7   325   20   10   7.8   4.3   17.9  64.2    -1.7    758  3.9
 14500  -10.2  13.6   330   21   11   8.0   4.4   17.6  63.6    -2.0    708  3.6
 14000   -9.0  15.8   330   22   11   7.2   4.0   17.2  63.0    -2.3    660  3.4
 13500   -8.0  17.6   330   23   12   7.3   4.0   16.8  62.3    -2.7    613  3.1
 13000   -7.0  19.4   330   24   12   6.4   3.5   16.4  61.4    -3.2    568  2.9
 12500   -6.1  21.0   330   24   12   6.2   3.4   15.8  60.4    -3.8    527  2.7
 12000   -5.2  22.6   330   23   12   6.0   3.3   15.2  59.4    -4.4    486  2.5
 11500   -4.4  24.1   330   22   12   6.0   3.3   14.6  58.3    -5.1    446  2.3
 11000   -3.5  25.7   335   22   11   5.8   3.2   14.0  57.2    -5.7    407  2.1
 10500   -2.7  27.1   335   20   10   6.5   3.6   13.3  56.0    -6.4    368  1.9
 10250   -2.3  27.9   335   20   10   3.0   1.6   13.0  55.4    -6.8    348  1.8
 10000   -2.2  28.0   340   20   10   3.5   1.9   12.4  54.3    -7.4    338  1.7
  9750   -1.8  28.8   340   19   10   7.4   4.0   12.1  53.8    -7.7    316  1.6
  9500   -1.3  29.7   340   19   10   6.8   3.7   11.9  53.4    -8.0    295  1.5
  9250   -0.8  30.6   345   18    9   5.3   2.9   11.6  53.0    -8.2    273  1.4
  9000   -0.5  31.1   345   18    9   4.1   2.2   11.2  52.2    -8.7    257  1.3
  8750   -0.1  31.8   350   18    9   5.8   3.2   10.8  51.5    -9.1    238  1.2
  8500    0.3  32.5   350   18    9   6.3   3.4   10.6  51.0    -9.4    218  1.1
  8250    0.8  33.4   355   19   10   7.1   3.9   10.3  50.6    -9.7    196  1.0
  8000    1.3  34.3   355   18    9   7.7   4.2   10.1  50.3    -9.9    172  0.9
  7750    1.9  35.4   355   18    9   7.9   4.3   10.0  50.0   -10.0    147  0.7
  7500    2.5  36.5   350   17    9   7.7   4.2    9.9  49.7   -10.2    122  0.6
  7250    3.0  37.4   350   17    9   7.0   3.8    9.7  49.4   -10.4     99  0.5
  7000    3.5  38.3   350   16    8   7.0   3.9    9.4  49.0   -10.7     77  0.4
  6750    4.0  39.2   355   16    8   6.6   3.6    9.2  48.6   -10.9     54  0.3
  6500    4.5  40.1   355   15    8   6.2   3.4    9.0  48.2   -11.3     33  0.2
  6250    4.9  40.8   355   14    7   6.3   3.5    8.7  47.7   -11.6     13  0.1
  6000    5.4  41.7   355   12    6   6.1   3.3    8.4  47.2   -11.9      M    M
  5750    5.8  42.4   360   11    6   4.5   2.4    8.1  46.6   -12.2      M    M
  5500    5.9  42.6   350    7    4   2.5   1.4    7.7  45.8   -12.8      M    M

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

           10/02/2014 at 0900 MDT          |       10/02/2014 at 1200 MDT
                                           |
K index... +7.6  LI... +3.2                | K index... -17.4  LI... +5.9
CAPE... 0.0  CIN... M                      | 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 -57.8 -72.0  270  29 15   1.3   0.7 | -58.1 -72.6  290  40 21   0.7   0.4
 45000 -55.9 -68.6  280  32 17   1.0   0.5 | -57.2 -71.0  300  52 27  -1.5  -0.8
 40000 -54.4 -65.9  305  30 16   1.0   0.5 | -59.2 -74.6  340  55 28  -1.1  -0.6
 38000 -52.9 -63.2  325  37 19   3.3   1.8 | -56.8 -70.2  340  55 28   6.1   3.4
 36000 -50.9 -59.6  340  50 26   3.3   1.8 | -53.1 -63.6  335  52 27   6.1   3.4
 34000 -48.5 -55.3  345  60 31   5.6   3.1 | -49.2 -56.6  335  52 27   7.2   4.0
 32000 -45.1 -49.2  345  58 30   5.7   3.1 | -44.9 -48.8  330  58 30   7.2   4.0
 30000 -41.5 -42.7  350  55 29   7.0   3.9 | -40.4 -40.7  330  62 32   7.8   4.3
 29000 -38.8 -37.8  350  54 28   7.1   3.9 | -37.5 -35.5  335  61 31   7.8   4.3
 28000 -36.7 -34.1  350  52 27   7.1   3.9 | -35.1 -31.2  335  61 31   7.8   4.3
 27000 -34.6 -30.3  355  50 26   7.1   3.9 | -32.8 -27.0  340  59 31   8.2   4.5
 26000 -32.4 -26.3  350  47 24   7.1   3.9 | -30.3 -22.5  340  55 28   8.2   4.5
 25000 -30.3 -22.5  350  44 22   7.1   3.9 | -27.9 -18.2  345  51 26   8.2   4.5
 24000 -28.2 -18.8  350  40 21   6.7   3.7 | -25.5 -13.9  350  48 25   6.3   3.5
 23000 -26.2 -15.2  350  37 19   6.5   3.5 | -23.7 -10.7  350  45 23   6.2   3.4
 22000 -24.3 -11.7  345  34 18   6.5   3.5 | -21.8  -7.2  345  43 22   6.3   3.4
 21000 -22.4  -8.3  345  31 16   5.7   3.1 | -19.9  -3.8  345  41 21   7.5   4.1
 20000 -20.7  -5.3  345  28 14   5.8   3.2 | -17.6   0.3  345  39 20   7.4   4.0
 19500 -19.9  -3.8  340  26 14   5.8   3.2 | -16.5   2.3  345  39 20   7.4   4.1
 19000 -19.0  -2.2  340  25 13   5.8   3.2 | -15.4   4.3  345  38 20   7.5   4.1
 18500 -18.1  -0.6  340  24 12   6.9   3.8 | -14.4   6.1  345  37 19   5.9   3.3
 18000 -17.0   1.4  340  23 12   7.1   3.9 | -13.5   7.7  345  36 19   5.8   3.2
 17500 -16.0   3.2  340  23 12   7.1   3.9 | -12.6   9.3  345  36 18   5.5   3.0
 17000 -15.0   5.0  340  23 12   6.7   3.7 | -11.9  10.6  345  34 17   4.6   2.5
 16500 -14.0   6.8  345  23 12   6.8   3.7 | -11.2  11.8  345  31 16   4.7   2.6
 16000 -13.0   8.6  345  23 12   6.6   3.6 | -10.5  13.1  345  29 15   4.5   2.5
 15500 -12.0  10.4  345  23 12   6.6   3.6 |  -9.8  14.4  340  27 14   4.5   2.5
 15000 -11.0  12.2  345  23 12   6.6   3.6 |  -9.1  15.6  340  25 13   5.0   2.7
 14500  -9.6  14.7  345  23 12   6.7   3.7 |  -8.0  17.6  335  23 12   5.2   2.8
 14000  -8.7  16.3  345  23 12   5.8   3.2 |  -7.3  18.9  330  22 11   5.3   2.9
 13500  -7.9  17.8  345  23 12   5.9   3.2 |  -6.5  20.3  330  21 11   5.3   2.9
 13000  -7.0  19.4  345  23 12   5.8   3.2 |  -5.7  21.7  330  20 10   5.6   3.1
 12500  -6.2  20.8  345  23 12   5.8   3.2 |  -4.9  23.2  330  19 10   5.6   3.1
 12000  -5.3  22.5  340  22 11   6.0   3.3 |  -4.0  24.8  330  19 10   6.4   3.5
 11500  -4.5  23.9  340  21 11   6.1   3.3 |  -3.1  26.4  335  19 10   6.4   3.5
 11000  -3.6  25.5  340  20 10   6.3   3.4 |  -2.1  28.2  335  20 10   6.8   3.8
 10500  -2.7  27.1  340  19 10   7.1   3.9 |  -1.1  30.0  340  19 10   7.7   4.2
 10250  -2.2  28.0  340  18  9   3.3   1.8 |  -0.6  30.9  340  19 10   3.6   2.0
 10000  -2.1  28.2  340  17  9   3.6   2.0 |  -0.5  31.1  340  19 10   5.5   3.0
  9750  -1.6  29.1  335  16  8   7.7   4.2 |   0.3  32.5  340  19 10  10.9   6.0
  9500  -1.2  29.8  335  14  7   6.8   3.7 |   1.0  33.8  340  18  9   9.9   5.4
  9250  -0.7  30.7  330  13  7   5.8   3.2 |   1.7  35.1  340  18  9   7.4   4.1
  9000  -0.3  31.5  325  12  6   5.9   3.2 |   2.1  35.8  335  17  9   6.1   3.4
  8750   0.3  32.5  325  11  6   8.6   4.7 |   2.6  36.7  330  16  8   8.5   4.6
  8500   0.9  33.6  315  11  6   8.6   4.7 |   3.2  37.8  325  14  7   8.2   4.5
  8250   1.5  34.7  310  11  6   7.1   3.9 |   3.8  38.8  320  13  7   7.7   4.2
  8000   2.0  35.6  310  11  6   6.6   3.6 |   4.3  39.7  310  12  6   7.8   4.3
  7750   2.5  36.5  305  12  6   5.8   3.2 |   4.9  40.8  305  10  5   8.2   4.5
  7500   2.9  37.2  305  12  6   6.3   3.4 |   5.4  41.7  295   9  5   9.3   5.1
  7250   3.4  38.1  305  11  6   7.4   4.0 |   6.2  43.2  295   9  5  10.3   5.6
  7000   3.9  39.0  310  10  5   7.1   3.9 |   6.9  44.4  290   9  4  10.1   5.6
  6750   4.5  40.1  310   9  5   8.1   4.4 |   7.7  45.9  290   8  4  10.2   5.6
  6500   5.1  41.2  310   8  4   8.1   4.5 |   8.4  47.1  290   8  4  10.6   5.8
  6250   5.6  42.1  305   7  3   7.3   4.0 |   9.3  48.7  290   8  4  11.5   6.3
  6000   6.1  43.0  295   5  3   8.2   4.5 |  10.1  50.2  290   8  4   9.2   5.0
  5750   6.8  44.2  290   5  2  11.1   6.1 |  10.8  51.4  290   8  4  12.9   7.1
  5500   7.7  45.9  280   4  2  13.9   7.6 |  12.2  54.0  290   7  4  25.4  14.0

           10/02/2014 at 1500 MDT          |       10/02/2014 at 1800 MDT
                                           |
K index... -10.3  LI... +5.0               | K index... +9.3  LI... +3.7
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.0
                                           |
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 -58.4 -73.1  285  50 25   2.1   1.2 | -58.4 -73.1  285  50 26   2.9   1.6
 45000 -55.5 -67.9  300  61 32  -1.1  -0.6 | -54.7 -66.5  295  66 34  -2.2  -1.2
 40000 -57.3 -71.1  310  56 29  -1.1  -0.6 | -58.2 -72.8  320  75 38  -2.2  -1.2
 38000 -56.2 -69.2  310  55 28   3.1   1.7 | -56.9 -70.4  325  79 40   4.0   2.2
 36000 -54.3 -65.7  315  55 28   3.1   1.7 | -54.4 -65.9  330  82 42   4.0   2.2
 34000 -51.4 -60.5  315  55 28   8.1   4.4 | -51.2 -60.2  330  82 42   8.0   4.4
 32000 -46.5 -51.7  320  55 28   8.1   4.4 | -46.4 -51.5  335  76 39   8.0   4.4
 30000 -40.8 -41.4  320  54 28   9.0   4.9 | -40.6 -41.1  330  67 35   9.4   5.2
 29000 -38.2 -36.8  325  53 27   9.0   4.9 | -37.8 -36.0  330  63 32   9.4   5.2
 28000 -35.5 -31.9  325  52 27   9.0   4.9 | -35.0 -31.0  330  58 30   9.4   5.2
 27000 -32.8 -27.0  325  49 25   8.6   4.7 | -32.2 -26.0  325  53 27   8.7   4.8
 26000 -30.3 -22.5  325  44 22   8.6   4.7 | -29.6 -21.3  320  48 25   8.7   4.8
 25000 -27.7 -17.9  325  38 20   8.6   4.7 | -27.0 -16.6  315  43 22   8.7   4.8
 24000 -25.2 -13.4  330  35 18   7.6   4.2 | -24.6 -12.3  310  40 21   6.3   3.4
 23000 -22.9  -9.2  325  36 19   7.7   4.2 | -22.6  -8.7  310  43 22   6.6   3.6
 22000 -20.6  -5.1  325  38 19   7.7   4.2 | -20.7  -5.3  315  46 23   6.6   3.6
 21000 -18.4  -1.1  325  39 20   6.3   3.4 | -18.8  -1.8  315  47 24   6.1   3.4
 20000 -16.5   2.3  320  40 20   6.4   3.5 | -17.0   1.4  315  45 23   6.2   3.4
 19500 -15.6   3.9  320  40 21   6.4   3.5 | -16.1   3.0  315  44 23   6.2   3.4
 19000 -14.6   5.7  320  40 21   6.5   3.6 | -15.2   4.6  315  43 22   6.3   3.4
 18500 -13.7   7.3  320  40 21   5.8   3.2 | -14.3   6.3  315  42 22   5.8   3.2
 18000 -12.9   8.8  320  40 20   5.8   3.2 | -13.4   7.9  315  41 21   5.9   3.2
 17500 -12.0  10.4  320  39 20   5.8   3.2 | -12.6   9.3  315  40 21   6.6   3.6
 17000 -11.1  12.0  320  37 19   5.9   3.2 | -11.5  11.3  315  40 21   7.2   4.0
 16500 -10.2  13.6  320  35 18   6.0   3.3 | -10.4  13.3  320  40 21   7.2   4.0
 16000  -9.3  15.3  320  33 17   4.7   2.6 |  -9.4  15.1  320  39 20   6.1   3.3
 15500  -8.6  16.5  315  30 16   4.9   2.7 |  -8.5  16.7  320  39 20   6.1   3.4
 15000  -7.5  18.5  310  28 14   4.2   2.3 |  -7.0  19.4  320  38 20   7.1   3.9
 14500  -6.9  19.6  310  26 14   4.1   2.3 |  -5.9  21.4  320  38 19   7.0   3.9
 14000  -6.1  21.0  305  25 13   6.3   3.4 |  -4.9  23.2  320  37 19   6.1   3.3
 13500  -5.2  22.6  305  24 12   6.1   3.3 |  -4.0  24.8  315  37 19   6.1   3.3
 13000  -4.3  24.3  305  22 12   6.6   3.6 |  -3.0  26.6  315  36 19   7.0   3.8
 12500  -3.4  25.9  305  21 11   6.4   3.5 |  -2.0  28.4  310  35 18   7.0   3.8
 12000  -2.3  27.9  305  20 10   8.5   4.6 |  -1.0  30.2  305  34 17   6.0   3.3
 11500  -1.0  30.2  305  19 10   8.7   4.8 |  -0.1  31.8  300  32 16   5.9   3.2
 11000   0.1  32.2  305  18 10   7.1   3.9 |   0.8  33.4  295  30 15   7.4   4.0
 10500   1.1  34.0  305  18  9   7.9   4.3 |   1.8  35.2  295  27 14   8.3   4.5
 10250   1.6  34.9  305  18  9   3.9   2.2 |   2.3  36.1  290  26 13   3.8   2.1
 10000   1.8  35.2  305  17  9   4.3   2.4 |   2.5  36.5  290  25 13   5.9   3.3
  9750   2.3  36.1  305  15  7   8.5   4.7 |   3.3  37.9  290  23 12  11.9   6.5
  9500   2.8  37.0  305  12  6   7.7   4.2 |   4.1  39.4  290  22 11  10.7   5.9
  9250   3.3  37.9  305  10  5   6.9   3.8 |   4.9  40.8  295  20 10   8.4   4.6
  9000   3.8  38.8  310   9  4   7.9   4.3 |   5.4  41.7  295  18  9   7.6   4.2
  8750   4.5  40.1  310   8  4  10.2   5.6 |   6.0  42.8  290  16  8   9.6   5.3
  8500   5.2  41.4  310   7  4   9.9   5.4 |   6.7  44.1  290  15  8   9.1   5.0
  8250   5.9  42.6  310   7  3   9.8   5.4 |   7.4  45.3  290  13  7   9.0   5.0
  8000   6.7  44.1  310   6  3   9.9   5.4 |   8.1  46.6  290  12  6   8.9   4.9
  7750   7.4  45.3  310   6  3  10.4   5.7 |   8.7  47.7  290  11  6   8.6   4.7
  7500   8.2  46.8  310   6  3  10.4   5.7 |   9.4  48.9  285  10  5   9.2   5.0
  7250   9.0  48.2  310   6  3  10.0   5.5 |  10.1  50.2  285  10  5  10.1   5.5
  7000   9.7  49.5  310   6  3  10.0   5.5 |  10.8  51.4  285   9  5  10.0   5.5
  6750  10.4  50.7  310   6  3   9.8   5.4 |  11.5  52.7  285   8  4   9.2   5.0
  6500  11.2  52.2  310   6  3  10.2   5.6 |  12.2  54.0  285   8  4   9.5   5.2
  6250  12.0  53.6  310   6  3  11.1   6.1 |  12.9  55.2  285   7  4  10.3   5.6
  6000  12.8  55.0  310   5  3   9.7   5.3 |  13.7  56.7  285   7  3  10.0   5.5
  5750  13.5  56.3  310   5  3  12.8   7.0 |  14.4  57.9  285   6  3   8.7   4.8
  5500  14.8  58.6  315   5  3  22.4  12.3 |  14.9  58.8  290   5  3   7.0   3.8
________________________________________________________________________________

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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