Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 310013
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1813 MDT Saturday, August 30, 2014

This forecast is for Sunday, August 31, 2014:

If the trigger temperature of 82.6 F/28.1 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 236 ft/min (1.2 m/s)
   Maximum height of thermals.................. 10662 ft MSL (5375 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6398 ft MSL (1111 ft AGL)
Thermal soaring outlook for Monday 09/01....... Excellent

Wave Soaring Index............................. Fair
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....................... 16859 ft MSL (11572 ft AGL)
Wave soaring outlook for Monday 09/01.......... Poor

Remarks...

Sunrise/Sunset.................... 06:26:34 / 19:33:35 MDT
Total possible sunshine........... 13 hr 7 min 1 sec (787 min 1 sec)
Altitude of sun at 12:59:38 MDT... 58.69 degrees

Upper air data from numerical model forecast valid on 08/31/2014 at 0600 MDT

Freezing level.................. 15202 ft MSL (9915 ft AGL)
Convective condensation level... 16709 ft MSL (11422 ft AGL)
Lifted condensation level....... 16072 ft MSL (10785 ft AGL)
Lifted index.................... -1.8
K index......................... +23.0

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  -61.6 -78.9   270   37   19   3.0   1.7      M     M       M      M    M
 45000  -57.4 -71.3   265   55   28   1.4   0.8      M     M       M      M    M
 40000  -55.1 -67.2   265   62   32   4.4   2.4      M     M       M      M    M
 38000  -51.9 -61.4   265   61   31   5.3   2.9      M     M       M      M    M
 36000  -48.8 -55.8   260   59   31   5.3   2.9      M     M       M      M    M
 34000  -44.1 -47.4   255   55   28   9.1   5.0      M     M       M      M    M
 32000  -37.9 -36.2   250   47   24   9.1   5.0      M     M       M      M    M
 30000  -32.7 -26.9   255   46   24   8.7   4.8   42.8 109.1    11.0      M    M
 29000  -30.1 -22.2   255   46   24   8.8   4.8   42.5 108.4    10.8      M    M
 28000  -27.5 -17.5   260   47   24   8.7   4.8   42.2 108.0    10.7      M    M
 27000  -25.7 -14.3   260   46   24   5.2   2.8   40.6 105.1     9.6      M    M
 26000  -24.2 -11.6   260   45   23   5.2   2.9   38.9 102.0     8.3      M    M
 25000  -22.6  -8.7   260   43   22   5.2   2.9   37.3  99.1     7.0      M    M
 24000  -20.9  -5.6   260   40   21   6.2   3.4   35.8  96.4     5.9      M    M
 23000  -19.1  -2.4   255   36   18   6.2   3.4   34.5  94.0     4.8      M    M
 22000  -17.2   1.0   250   32   16   6.1   3.3   33.3  91.9     3.9      M    M
 21000  -14.9   5.2   250   29   15   8.6   4.7   32.5  90.6     3.2      M    M
 20000  -12.4   9.7   250   27   14   8.6   4.7   32.1  89.8     2.9      M    M
 19500  -11.1  12.0   250   27   14   8.6   4.7   31.9  89.5     2.7      M    M
 19000   -9.9  14.2   250   26   13   8.7   4.8   31.8  89.2     2.6      M    M
 18500   -8.6  16.5   255   25   13   8.8   4.8   31.6  88.9     2.4      M    M
 18000   -7.3  18.9   260   25   13   8.9   4.9   31.4  88.6     2.2      M    M
 17500   -6.1  21.0   265   26   13   7.7   4.2   31.2  88.1     2.0      M    M
 17000   -4.9  23.2   270   27   14   7.8   4.3   30.8  87.5     1.7      M    M
 16500   -3.8  25.2   275   28   14   8.3   4.6   30.5  87.0     1.4      M    M
 16000   -2.5  27.5   275   27   14   8.8   4.8   30.4  86.6     1.3      M    M
 15500   -0.5  31.1   280   27   14   9.0   4.9   30.1  86.3     1.1      M    M
 15000    0.9  33.6   280   26   13   9.1   5.0   30.0  86.0     0.9      M    M
 14500    2.2  36.0   280   25   13   9.2   5.1   29.9  85.8     0.8      M    M
 14000    3.6  38.5   280   24   12   9.5   5.2   29.9  85.7     0.8      M    M
 13500    5.0  41.0   280   23   12   9.4   5.2   29.8  85.7     0.7      M    M
 13000    6.3  43.3   280   22   11   9.0   4.9   29.7  85.5     0.6      M    M
 12500    7.7  45.9   285   21   11   9.0   4.9   29.6  85.3     0.5      M    M
 12000    9.0  48.2   285   21   11   9.4   5.2   29.5  85.1     0.4      M    M
 11500   10.4  50.7   285   22   11   9.6   5.3   29.5  85.0     0.3      M    M
 11000   11.7  53.1   285   23   12   7.8   4.3   29.3  84.7     0.2      M    M
 10500   12.9  55.2   285   24   12   9.3   5.1   29.0  84.2    -0.1    415  2.1
 10250   13.7  56.7   285   24   12  11.2   6.1   29.1  84.3    -0.1    384  2.0
 10000   14.4  57.9   285   23   12   9.5   5.2   29.1  84.4    -0.0    354  1.8
  9750   15.1  59.2   280   23   12   8.9   4.9   29.0  84.3    -0.1    327  1.7
  9500   15.8  60.4   280   23   12   8.9   4.9   29.0  84.2    -0.2    299  1.5
  9250   16.4  61.5   280   23   12   9.4   5.2   28.9  84.1    -0.2    272  1.4
  9000   17.1  62.8   280   23   12   9.2   5.0   28.9  84.1    -0.2    243  1.2
  8750   17.8  64.0   280   22   11   8.5   4.7   28.8  83.9    -0.3    217  1.1
  8500   18.4  65.1   275   22   11   8.6   4.7   28.8  83.8    -0.4    190  1.0
  8250   19.1  66.4   275   21   11   9.0   4.9   28.7  83.6    -0.5    164  0.8
  8000   19.7  67.5   270   20   10   7.8   4.3   28.6  83.5    -0.6    137  0.7
  7750   20.2  68.4   265   20   10   6.5   3.6   28.4  83.1    -0.9    115  0.6
  7500   20.7  69.3   260   19   10   6.7   3.7   28.1  82.6    -1.1     93  0.5
  7250   21.2  70.2   255   19   10   6.8   3.7   27.9  82.2    -1.3     71  0.4
  7000   21.6  70.9   245   19   10   5.7   3.1   27.7  81.8    -1.6     49  0.3
  6750   22.0  71.6   240   19   10   5.8   3.2   27.3  81.2    -1.9     30  0.2
  6500   22.3  72.1   235   19   10  -0.3  -0.2   26.9  80.4    -2.4     14  0.1
  6250   21.8  71.2   230   19   10 -11.4  -6.2   25.7  78.2    -3.7     23  0.1
  6000   20.7  69.3   230   18    9 -14.2  -7.8   23.9  75.0    -5.5     49  0.2
  5750   19.4  66.9   230   17    9 -19.6 -10.8   22.0  71.6    -7.6     81  0.4
  5500   17.3  63.1   225   14    7 -26.9 -14.8   19.4  67.0   -10.4    135  0.7

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

           08/31/2014 at 0900 MDT          |       08/31/2014 at 1200 MDT
                                           |
K index... +21.7  LI... 0.0                | K index... +22.0  LI... -1.4
CAPE... +4.8  CIN... -251.4                | CAPE... +309.5  CIN... -71.8
                                           |
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 -60.8 -77.4  265  38 19   2.8   1.5 | -60.8 -77.4  275  41 21   1.5   0.8
 45000 -56.8 -70.2  260  60 31   1.6   0.9 | -58.2 -72.8  275  66 34   2.8   1.5
 40000 -54.3 -65.7  270  65 33   3.0   1.6 | -54.0 -65.2  280  77 40   3.9   2.1
 38000 -51.8 -61.2  265  61 31   4.2   2.3 | -51.1 -60.0  280  73 37   4.7   2.6
 36000 -49.3 -56.7  265  57 29   4.1   2.3 | -48.3 -54.9  280  68 35   4.7   2.6
 34000 -45.4 -49.7  265  53 27   8.1   4.4 | -44.4 -47.9  280  63 32   7.6   4.2
 32000 -39.9 -39.8  260  48 25   8.1   4.5 | -39.3 -38.7  275  56 29   7.6   4.2
 30000 -34.7 -30.5  255  43 22   9.1   5.0 | -34.8 -30.6  270  50 26   7.5   4.1
 29000 -31.9 -25.4  255  41 21   9.2   5.0 | -32.5 -26.5  265  47 24   7.5   4.1
 28000 -29.2 -20.6  255  39 20   9.4   5.1 | -30.2 -22.4  260  45 23   7.5   4.1
 27000 -27.0 -16.6  255  38 20   6.7   3.7 | -28.0 -18.4  260  44 23   7.6   4.2
 26000 -25.0 -13.0  260  38 19   6.8   3.7 | -25.7 -14.3  260  45 23   7.7   4.2
 25000 -23.0  -9.4  265  37 19   6.8   3.7 | -23.4 -10.1  260  45 23   7.7   4.2
 24000 -21.1  -6.0  265  37 19   6.6   3.6 | -21.1  -6.0  260  45 23   7.8   4.3
 23000 -19.1  -2.4  260  37 19   6.6   3.6 | -18.8  -1.8  260  46 24   7.8   4.3
 22000 -17.1   1.2  260  38 19   6.5   3.6 | -16.4   2.5  260  46 24   7.9   4.3
 21000 -15.0   5.0  255  38 20   7.8   4.3 | -14.2   6.4  265  47 24   7.5   4.1
 20000 -12.6   9.3  260  40 20   7.8   4.3 | -12.0  10.4  265  48 25   7.5   4.1
 19500 -11.5  11.3  260  40 21   7.9   4.3 | -10.9  12.4  265  48 25   7.6   4.1
 19000 -10.3  13.5  260  41 21   8.2   4.5 |  -9.8  14.4  265  48 25   8.0   4.4
 18500  -9.0  15.8  260  41 21   8.6   4.7 |  -8.6  16.5  265  48 25   8.7   4.8
 18000  -7.8  18.0  260  41 21   8.7   4.8 |  -7.3  18.9  265  47 24   8.8   4.8
 17500  -6.6  20.1  260  40 20   8.0   4.4 |  -6.1  21.0  260  47 24   7.7   4.2
 17000  -5.4  22.3  260  37 19   8.1   4.4 |  -5.0  23.0  260  45 23   7.6   4.2
 16500  -4.2  24.4  255  34 18   8.6   4.7 |  -3.9  25.0  260  44 23   7.5   4.1
 16000  -2.1  28.2  255  29 15   9.3   5.1 |  -2.2  28.0  255  39 20   7.4   4.1
 15500  -0.8  30.6  255  26 13   8.6   4.7 |  -1.1  30.0  255  36 18   7.8   4.3
 15000   0.4  32.7  260  24 12   8.2   4.5 |   0.0  32.0  250  33 17   8.1   4.4
 14500   1.6  34.9  260  23 12   8.1   4.4 |   1.2  34.2  250  30 16   8.1   4.5
 14000   2.8  37.0  260  21 11   7.8   4.3 |   2.4  36.3  250  28 14   8.3   4.5
 13500   4.0  39.2  260  19 10   7.9   4.3 |   3.7  38.7  250  25 13   8.3   4.5
 13000   5.2  41.4  260  17  9   8.4   4.6 |   4.9  40.8  250  23 12   8.2   4.5
 12500   6.4  43.5  260  15  8   8.4   4.6 |   6.1  43.0  250  21 11   8.2   4.5
 12000   7.6  45.7  260  13  7   8.2   4.5 |   7.3  45.1  250  18  9   7.9   4.3
 11500   8.8  47.8  265  11  6   8.4   4.6 |   8.5  47.3  245  16  8   8.0   4.4
 11000  10.0  50.0  275  10  5   7.0   3.8 |   9.6  49.3  245  13  7   7.6   4.1
 10500  11.0  51.8  285  10  5   8.1   4.4 |  10.8  51.4  240  11  6   8.1   4.4
 10250  11.7  53.1  290  11  5  10.3   5.7 |  11.4  52.5  235  10  5   9.2   5.0
 10000  12.5  54.5  295  11  6   9.2   5.0 |  12.1  53.8  235   9  4   8.5   4.6
  9750  13.1  55.6  300  11  6   8.2   4.5 |  12.7  54.9  230   8  4   7.7   4.2
  9500  13.7  56.7  300  12  6   8.4   4.6 |  13.3  55.9  230   7  3   8.1   4.4
  9250  14.3  57.7  305  12  6   8.4   4.6 |  13.9  57.0  220   6  3   7.5   4.1
  9000  15.0  59.0  305  13  7   8.5   4.6 |  14.4  57.9  220   5  2   7.3   4.0
  8750  15.6  60.1  300  14  7   8.5   4.6 |  14.9  58.8  220   4  2   7.8   4.3
  8500  16.2  61.2  300  15  8   8.2   4.5 |  15.5  59.9  210   3  1   7.4   4.0
  8250  16.9  62.4  300  16  8   9.7   5.3 |  16.1  61.0  195   1  1   8.9   4.9
  8000  17.6  63.7  300  16  8   9.2   5.0 |  16.7  62.1  075   1  1   9.2   5.0
  7750  18.2  64.8  300  16  8   7.4   4.1 |  17.2  63.0  060   3  1   7.9   4.3
  7500  18.7  65.7  300  17  9   7.4   4.1 |  17.7  63.9  055   4  2   8.5   4.7
  7250  19.2  66.6  305  17  9   6.5   3.6 |  18.4  65.1  055   5  3   9.9   5.5
  7000  19.7  67.5  305  17  9   5.4   3.0 |  19.2  66.6  055   5  3  10.5   5.8
  6750  20.1  68.2  310  17  8   5.3   2.9 |  19.9  67.8  055   5  3   9.3   5.1
  6500  20.3  68.5  310  16  8   1.4   0.8 |  20.6  69.1  055   6  3  10.0   5.5
  6250  20.1  68.2  315  14  7  -3.2  -1.8 |  21.4  70.5  055   6  3  11.6   6.4
  6000  19.8  67.6  315  11  6  -3.8  -2.1 |  22.2  72.0  055   6  3  11.6   6.4
  5750  19.3  66.7  315   8  4  -5.3  -2.9 |  23.1  73.6  055   5  3  11.0   6.0
  5500  18.8  65.8  300   4  2  -0.4  -0.2 |  24.0  75.2  050   5  3  16.1   8.8

           08/31/2014 at 1500 MDT          |       08/31/2014 at 1800 MDT
                                           |
K index... +27.2  LI... -3.4               | K index... +27.3  LI... -2.9
CAPE... +522.7  CIN... -23.8               | CAPE... +389.9  CIN... -24.0
                                           |
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 -60.3 -76.5  275  38 20   0.8   0.4 | -60.1 -76.2  275  35 18   0.9   0.5
 45000 -58.5 -73.3  280  68 35   2.7   1.5 | -58.1 -72.6  280  66 34   2.8   1.5
 40000 -54.3 -65.7  285  92 48   5.5   3.0 | -53.7 -64.7  280  91 47   5.3   2.9
 38000 -50.4 -58.7  285  91 47   6.6   3.6 | -50.0 -58.0  280  89 46   6.2   3.4
 36000 -46.5 -51.7  285  89 46   6.6   3.6 | -46.3 -51.3  280  87 45   6.2   3.4
 34000 -42.5 -44.5  280  83 43   6.7   3.7 | -42.4 -44.3  280  84 43   6.6   3.6
 32000 -37.9 -36.2  280  73 37   6.7   3.7 | -38.0 -36.4  280  78 40   6.6   3.6
 30000 -33.9 -29.0  275  62 32   6.8   3.7 | -33.8 -28.8  275  67 34   7.0   3.9
 29000 -31.9 -25.4  270  57 29   6.8   3.7 | -31.7 -25.1  275  61 31   7.1   3.9
 28000 -29.8 -21.6  260  52 27   6.7   3.7 | -29.6 -21.3  270  55 28   7.2   3.9
 27000 -27.6 -17.7  260  51 26   7.7   4.2 | -27.6 -17.7  270  53 27   6.8   3.7
 26000 -25.3 -13.5  260  50 26   7.7   4.2 | -25.6 -14.1  270  54 28   6.8   3.7
 25000 -23.0  -9.4  265  50 26   7.7   4.2 | -23.6 -10.5  270  54 28   6.8   3.7
 24000 -20.8  -5.4  265  51 26   7.1   3.9 | -21.5  -6.7  270  54 28   7.0   3.8
 23000 -18.7  -1.7  265  52 27   7.1   3.9 | -19.5  -3.1  270  54 28   7.0   3.8
 22000 -16.6   2.1  265  53 27   7.1   3.9 | -17.4   0.7  265  54 28   7.0   3.8
 21000 -14.6   5.7  265  53 27   6.8   3.8 | -15.3   4.5  265  52 27   7.4   4.0
 20000 -12.6   9.3  265  52 27   6.9   3.8 | -13.1   8.4  265  48 25   7.4   4.1
 19500 -11.6  11.1  260  52 27   6.9   3.8 | -12.0  10.4  260  46 24   7.5   4.1
 19000 -10.6  12.9  260  51 26   7.3   4.0 | -11.0  12.2  260  45 23   7.8   4.3
 18500  -9.4  15.1  260  49 25   8.1   4.4 |  -9.8  14.4  260  42 22   8.3   4.6
 18000  -8.2  17.2  260  47 24   8.1   4.4 |  -8.6  16.5  260  39 20   8.3   4.6
 17500  -7.0  19.4  260  44 23   8.2   4.5 |  -7.3  18.9  260  36 19   8.6   4.7
 17000  -5.8  21.6  260  41 21   8.3   4.6 |  -6.1  21.0  260  34 17   8.7   4.8
 16500  -4.6  23.7  260  39 20   8.8   4.8 |  -4.8  23.4  260  31 16   9.1   5.0
 16000  -2.5  27.5  255  36 18   9.5   5.2 |  -2.7  27.1  260  29 15   9.6   5.3
 15500  -1.1  30.0  255  34 17   9.4   5.2 |  -1.2  29.8  260  28 14   9.6   5.3
 15000   0.3  32.5  255  32 17   9.4   5.1 |   0.2  32.4  265  27 14   9.6   5.3
 14500   1.7  35.1  255  31 16   9.4   5.2 |   1.6  34.9  265  26 14   9.6   5.3
 14000   3.1  37.6  255  30 15   9.7   5.3 |   3.1  37.6  265  25 13   9.5   5.2
 13500   4.5  40.1  255  29 15   9.7   5.3 |   4.5  40.1  270  23 12   9.5   5.2
 13000   5.9  42.6  255  27 14   8.8   4.8 |   5.8  42.4  270  22 11   9.3   5.1
 12500   7.2  45.0  250  25 13   9.0   4.9 |   7.2  45.0  270  21 11   9.3   5.1
 12000   8.4  47.1  250  22 11   7.8   4.3 |   8.6  47.5  275  19 10   8.8   4.8
 11500   9.6  49.3  240  18  9   8.0   4.4 |   9.9  49.8  275  16  8   8.9   4.9
 11000  10.6  51.1  230  15  7   7.1   3.9 |  11.1  52.0  280  14  7   7.8   4.3
 10500  11.6  52.9  220  11  5   7.9   4.3 |  12.2  54.0  285  12  6   8.4   4.6
 10250  12.3  54.1  210   9  4  10.0   5.5 |  12.9  55.2  285  10  5   9.8   5.4
 10000  13.0  55.4  200   7  4   9.8   5.4 |  13.6  56.5  290  10  5   9.3   5.1
  9750  13.7  56.7  190   7  3   9.2   5.1 |  14.2  57.6  295   9  5   9.0   4.9
  9500  14.3  57.7  180   6  3   9.3   5.1 |  14.9  58.8  300   9  4   8.9   4.9
  9250  15.0  59.0  170   5  3   9.6   5.3 |  15.6  60.1  305   8  4   9.8   5.4
  9000  15.7  60.3  170   5  3  10.0   5.5 |  16.3  61.3  305   8  4  10.3   5.6
  8750  16.5  61.7  165   5  3  10.0   5.5 |  17.0  62.6  310   8  4   9.7   5.3
  8500  17.2  63.0  165   5  3   9.8   5.4 |  17.8  64.0  310   8  4   9.6   5.3
  8250  17.9  64.2  160   5  3  10.7   5.8 |  18.5  65.3  315   8  4  10.6   5.8
  8000  18.7  65.7  160   5  2  10.3   5.7 |  19.3  66.7  315   8  4  10.3   5.6
  7750  19.4  66.9  160   5  2   9.2   5.1 |  20.0  68.0  320   8  4   9.1   5.0
  7500  20.2  68.4  160   5  2   9.5   5.2 |  20.7  69.3  320   8  4   9.4   5.1
  7250  20.9  69.6  155   4  2  10.2   5.6 |  21.4  70.5  320   8  4  10.2   5.6
  7000  21.7  71.1  155   4  2  10.4   5.7 |  22.2  72.0  320   8  4  10.4   5.7
  6750  22.4  72.3  155   4  2   9.4   5.2 |  22.9  73.2  325   8  4   9.3   5.1
  6500  23.1  73.6  150   4  2   9.7   5.3 |  23.6  74.5  325   8  4   9.4   5.2
  6250  23.9  75.0  150   4  2  10.6   5.8 |  24.3  75.7  325   8  4  10.2   5.6
  6000  24.7  76.5  150   4  2  11.1   6.1 |  25.1  77.2  325   7  4  10.4   5.7
  5750  25.5  77.9  145   4  2   9.7   5.3 |  25.8  78.4  330   7  4   9.3   5.1
  5500  26.3  79.3  145   3  2  13.4   7.4 |  26.5  79.7  330   7  4   9.3   5.1
________________________________________________________________________________

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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