Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 200137
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1937 MDT Tuesday, August 19, 2014

This forecast is for Wednesday, August 20, 2014:

If the trigger temperature of 77.3 F/25.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 906 ft/min (4.6 m/s)
   Maximum height of thermals.................. 14028 ft MSL (8741 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1000 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................. 11099 ft MSL (5812 ft AGL)
Thermal soaring outlook for Thursday 08/21..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT).........
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 19307 ft MSL (14020 ft AGL)
Wave soaring outlook for Thursday 08/21........ Poor

Remarks...

Sunrise/Sunset.................... 06:16:16 / 19:49:56 MDT
Total possible sunshine........... 13 hr 33 min 40 sec (813 min 40 sec)
Altitude of sun at 13:02:43 MDT... 62.50 degrees

Upper air data from numerical model forecast valid on 08/20/2014 at 0600 MDT

Freezing level.................. 15947 ft MSL (10660 ft AGL)
Convective condensation level... 14171 ft MSL (8884 ft AGL)
Lifted condensation level....... 14160 ft MSL (8873 ft AGL)
Lifted index.................... -2.0
K index......................... +26.1

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  -64.4 -83.9   260   36   19   1.0   0.5      M     M       M      M    M
 45000  -61.1 -78.0   265   56   29   4.9   2.7      M     M       M      M    M
 40000  -53.2 -63.8   255   53   27   7.8   4.3      M     M       M      M    M
 38000  -48.5 -55.3   250   48   25   7.9   4.3      M     M       M      M    M
 36000  -43.8 -46.8   245   43   22   7.8   4.3      M     M       M      M    M
 34000  -38.6 -37.5   240   39   20   8.9   4.9      M     M       M      M    M
 32000  -33.3 -27.9   230   35   18   8.8   4.8      M     M       M      M    M
 30000  -28.0 -18.4   235   33   17   7.6   4.2   48.1 118.5    13.8      M    M
 29000  -25.7 -14.3   235   33   17   7.6   4.2   47.3 117.1    13.3      M    M
 28000  -23.4 -10.1   240   32   17   7.3   4.0   46.6 115.9    12.9      M    M
 27000  -21.3  -6.3   240   30   15   7.0   3.9   45.4 113.8    12.1      M    M
 26000  -19.3  -2.7   240   27   14   7.1   3.9   44.4 111.9    11.4      M    M
 25000  -17.2   1.0   240   24   12   7.2   3.9   43.5 110.3    10.7      M    M
 24000  -15.3   4.5   235   24   12   6.2   3.4   42.2 108.0     9.8      M    M
 23000  -13.5   7.7   235   25   13   6.3   3.5   40.9 105.7     8.7      M    M
 22000  -11.7  10.9   230   27   14   6.4   3.5   39.8 103.6     7.8      M    M
 21000   -9.8  14.4   225   28   14   6.6   3.6   38.6 101.5     6.8      M    M
 20000   -8.0  17.6   225   30   15   6.6   3.6   37.5  99.5     5.8      M    M
 19500   -7.0  19.4   220   31   16   6.6   3.6   37.0  98.5     5.3      M    M
 19000   -6.1  21.0   220   32   16   6.2   3.4   36.5  97.7     4.9      M    M
 18500   -5.2  22.6   220   31   16   5.8   3.2   35.8  96.4     4.3      M    M
 18000   -4.4  24.1   220   31   16   5.7   3.1   35.1  95.2     3.7      M    M
 17500   -3.5  25.7   220   30   15   6.8   3.7   34.5  94.1     3.1      M    M
 17000   -2.5  27.5   220   29   15   6.7   3.7   34.0  93.2     2.7      M    M
 16500   -1.5  29.3   220   28   14   7.2   4.0   33.5  92.3     2.2      M    M
 16000   -0.4  31.3   220   26   14   7.6   4.2   33.1  91.6     1.9      M    M
 15500    0.7  33.3   220   25   13   7.6   4.1   32.8  91.0     1.6      M    M
 15000    2.2  36.0   225   22   11   6.7   3.7   32.0  89.7     0.9      M    M
 14500    3.2  37.8   230   20   10   6.5   3.5   31.5  88.8     0.4      M    M
 14000    4.1  39.4   235   17    9   6.0   3.3   30.9  87.7    -0.2    695  3.5
 13500    4.9  40.8   240   15    8   6.0   3.3   30.3  86.6    -0.8    655  3.3
 13000    5.8  42.4   250   13    7   5.9   3.2   29.7  85.5    -1.4    614  3.1
 12500    6.7  44.1   260   12    6   5.7   3.1   29.1  84.4    -1.9    573  2.9
 12000    7.7  45.9   270   11    6   8.0   4.4   28.6  83.5    -2.4    528  2.7
 11500    8.8  47.8   275   11    6   7.9   4.4   28.3  82.9    -2.7    479  2.4
 11000    9.9  49.8   280   11    6   5.8   3.2   27.9  82.1    -3.2    434  2.2
 10500   10.7  51.3   285   11    6   6.3   3.5   27.2  81.0    -3.8    393  2.0
 10250   11.2  52.2   285   11    6   8.4   4.6   27.1  80.7    -4.0    370  1.9
 10000   11.9  53.4   285   10    5   8.3   4.6   27.0  80.6    -4.1    344  1.7
  9750   12.4  54.3   285   10    5   7.4   4.0   26.8  80.2    -4.3    320  1.6
  9500   13.0  55.4   285    9    5   7.6   4.2   26.6  79.9    -4.5    296  1.5
  9250   13.5  56.3   290    9    5   7.6   4.2   26.5  79.6    -4.7    272  1.4
  9000   14.0  57.2   290    9    5   7.1   3.9   26.3  79.3    -4.9    249  1.3
  8750   14.5  58.1   295    9    4   6.8   3.7   26.1  78.9    -5.2    227  1.2
  8500   15.0  59.0   295    8    4   6.5   3.6   25.8  78.5    -5.4    205  1.0
  8250   15.5  59.9   300    8    4   8.1   4.4   25.6  78.1    -5.6    183  0.9
  8000   16.1  61.0   305    9    5   7.7   4.2   25.5  78.0    -5.8    157  0.8
  7750   16.6  61.9   305   10    5   5.7   3.1   25.3  77.5    -6.1    137  0.7
  7500   17.0  62.6   310   10    5   6.0   3.3   25.0  76.9    -6.4    117  0.6
  7250   17.4  63.3   310   11    5   6.0   3.3   24.7  76.4    -6.7     96  0.5
  7000   17.8  64.0   315   11    5   6.1   3.3   24.4  75.9    -7.0     76  0.4
  6750   18.3  64.9   315   10    5   6.3   3.5   24.1  75.4    -7.4     56  0.3
  6500   18.7  65.7   315   10    5   5.8   3.2   23.9  75.0    -7.7     36  0.2
  6250   19.0  66.2   310    8    4   5.0   2.7   23.5  74.4    -8.1     18  0.1
  6000   19.3  66.7   300    7    4   4.8   2.7   23.2  73.7    -8.5      2  0.0
  5750   19.6  67.3   285    6    3   3.2   1.8   22.8  73.0    -9.0      M    M
  5500   19.6  67.3   265    5    3   0.9   0.5   22.2  71.9    -9.7      M    M

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

           08/20/2014 at 0900 MDT          |       08/20/2014 at 1200 MDT
                                           |
K index... +27.2  LI... +0.8               | K index... +26.2  LI... +0.1
CAPE... 0.0  CIN... -13.1                  | CAPE... +0.2  CIN... -4.4
                                           |
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 -64.7 -84.5  255  38 19   0.3   0.2 | -64.6 -84.3  255  37 19   0.0   0.0
 45000 -61.6 -78.9  260  57 29   5.8   3.2 | -61.6 -78.9  255  56 29   6.4   3.5
 40000 -52.6 -62.7  250  53 27   7.5   4.1 | -51.8 -61.2  245  51 26   7.2   3.9
 38000 -48.1 -54.6  245  49 25   7.5   4.1 | -47.5 -53.5  240  49 25   7.2   3.9
 36000 -43.6 -46.5  240  46 24   7.4   4.1 | -43.2 -45.8  235  46 24   7.1   3.9
 34000 -38.5 -37.3  235  42 22   8.6   4.7 | -38.5 -37.3  230  44 22   7.9   4.3
 32000 -33.4 -28.1  230  38 20   8.6   4.7 | -33.8 -28.8  225  41 21   7.9   4.3
 30000 -28.2 -18.8  230  36 19   7.3   4.0 | -28.6 -19.5  225  41 21   7.7   4.2
 29000 -26.1 -15.0  230  35 18   7.3   4.0 | -26.3 -15.3  230  41 21   7.7   4.2
 28000 -23.9 -11.0  230  35 18   7.1   3.9 | -24.1 -11.4  230  41 21   7.3   4.0
 27000 -21.8  -7.2  230  34 18   7.0   3.8 | -22.0  -7.6  230  40 21   7.1   3.9
 26000 -19.7  -3.5  230  34 17   7.0   3.8 | -19.9  -3.8  230  39 20   7.1   3.9
 25000 -17.6   0.3  230  33 17   6.9   3.8 | -17.8  -0.0  235  39 20   7.2   4.0
 24000 -15.5   4.1  230  33 17   7.5   4.1 | -15.6   3.9  235  37 19   7.3   4.0
 23000 -13.3   8.1  230  32 16   7.7   4.2 | -13.4   7.9  235  35 18   7.4   4.0
 22000 -11.1  12.0  225  31 16   8.0   4.4 | -11.1  12.0  235  33 17   7.4   4.1
 21000  -9.1  15.6  230  30 15   6.9   3.8 |  -9.2  15.4  235  31 16   6.2   3.4
 20000  -7.1  19.2  230  28 14   6.9   3.8 |  -7.4  18.7  235  29 15   6.2   3.4
 19500  -6.1  21.0  230  27 14   6.9   3.8 |  -6.5  20.3  235  29 15   6.2   3.4
 19000  -5.1  22.8  230  26 13   6.5   3.5 |  -5.6  21.9  240  28 14   6.5   3.5
 18500  -4.2  24.4  230  25 13   6.2   3.4 |  -4.7  23.5  240  26 14   6.7   3.7
 18000  -3.3  26.1  230  25 13   6.3   3.4 |  -3.7  25.3  240  25 13   6.9   3.8
 17500  -2.5  27.5  230  23 12   5.2   2.9 |  -2.8  27.0  240  23 12   6.8   3.7
 17000  -1.8  28.8  230  21 11   5.3   2.9 |  -1.9  28.6  235  22 11   6.9   3.8
 16500  -1.0  30.2  230  19 10   4.5   2.5 |  -1.0  30.2  235  20 10   5.3   2.9
 16000  -0.5  31.1  230  17  9   3.9   2.1 |  -0.4  31.3  235  18  9   4.4   2.4
 15500   0.0  32.0  230  15  8   3.9   2.2 |   0.5  32.9  230  15  8   4.4   2.4
 15000   1.0  33.8  235  12  6   4.6   2.5 |   1.1  34.0  230  13  7   4.5   2.5
 14500   1.6  34.9  240  10  5   5.5   3.0 |   1.7  35.1  225  12  6   5.2   2.8
 14000   2.6  36.7  245   8  4   6.9   3.8 |   2.6  36.7  225  10  5   6.0   3.3
 13500   3.6  38.5  255   7  3   7.1   3.9 |   3.5  38.3  220   9  5   6.3   3.5
 13000   4.8  40.6  270   6  3   8.3   4.6 |   4.5  40.1  220   7  4   7.5   4.1
 12500   6.0  42.8  285   6  3   8.3   4.5 |   5.6  42.1  225   5  3   7.5   4.1
 12000   7.1  44.8  300   7  4   7.8   4.3 |   6.7  44.1  245   3  2   8.0   4.4
 11500   8.3  46.9  305   9  5   8.0   4.4 |   7.9  46.2  305   2  1   8.0   4.4
 11000   9.4  48.9  310  11  6   6.7   3.7 |   9.0  48.2  325   4  2   7.6   4.2
 10500  10.4  50.7  305  13  7   7.8   4.3 |  10.1  50.2  325   6  3  10.6   5.8
 10250  11.0  51.8  305  14  7   8.2   4.5 |  11.1  52.0  325   8  4   9.8   5.4
 10000  11.5  52.7  305  16  8   6.3   3.5 |  11.5  52.7  320   9  5   5.3   2.9
  9750  12.0  53.6  300  16  8   5.8   3.2 |  11.9  53.4  315   9  5   6.6   3.6
  9500  12.4  54.3  300  17  9   6.3   3.4 |  12.4  54.3  315  10  5   6.1   3.4
  9250  12.8  55.0  295  18  9   4.8   2.6 |  12.8  55.0  310  10  5   7.6   4.2
  9000  13.1  55.6  295  19 10   4.2   2.3 |  13.4  56.1  310  10  5   8.9   4.9
  8750  13.4  56.1  290  19 10   5.2   2.8 |  14.0  57.2  310   9  5   8.8   4.8
  8500  13.8  56.8  290  19 10   4.8   2.7 |  14.6  58.3  310   8  4   8.9   4.9
  8250  14.2  57.6  285  18  9   7.1   3.9 |  15.3  59.5  310   8  4   9.6   5.2
  8000  14.8  58.6  285  17  9   8.4   4.6 |  16.0  60.8  310   8  4   9.8   5.4
  7750  15.3  59.5  285  16  8   7.7   4.2 |  16.7  62.1  310   8  4   9.4   5.2
  7500  15.9  60.6  285  15  8   7.8   4.3 |  17.5  63.5  310   8  4   9.9   5.4
  7250  16.4  61.5  285  13  7   7.9   4.3 |  18.2  64.8  310   8  4  10.8   5.9
  7000  17.0  62.6  285  11  6   7.8   4.3 |  19.0  66.2  310   8  4  10.7   5.9
  6750  17.5  63.5  285   9  4   6.6   3.6 |  19.8  67.6  310   8  4   9.4   5.2
  6500  17.9  64.2  295   6  3   8.1   4.5 |  20.5  68.9  310   8  4  10.2   5.6
  6250  18.6  65.5  295   6  3  10.6   5.8 |  21.3  70.3  310   8  4  11.7   6.4
  6000  19.4  66.9  295   5  3  10.0   5.5 |  22.2  72.0  310   7  4  10.4   5.7
  5750  20.1  68.2  300   5  2  11.0   6.0 |  23.0  73.4  310   7  4  12.4   6.8
  5500  21.1  70.0  300   4  2  15.2   8.4 |  24.2  75.6  310   7  4  22.3  12.2

           08/20/2014 at 1500 MDT          |       08/20/2014 at 1800 MDT
                                           |
K index... +27.3  LI... -0.6               | K index... +29.4  LI... -1.1
CAPE... +21.9  CIN... -21.4                | CAPE... +98.2  CIN... -31.4
                                           |
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 -64.1 -83.4  250  33 17  -0.2  -0.1 | -64.3 -83.7  245  32 16   0.4   0.2
 45000 -61.3 -78.3  250  53 27   6.4   3.5 | -60.8 -77.4  245  51 26   6.5   3.6
 40000 -51.6 -60.9  245  53 27   7.2   3.9 | -50.9 -59.6  240  53 27   7.1   3.9
 38000 -47.3 -53.1  240  51 26   7.2   4.0 | -46.6 -51.9  240  51 26   7.1   3.9
 36000 -42.9 -45.2  235  49 25   7.2   3.9 | -42.4 -44.3  240  50 25   7.0   3.9
 34000 -37.6 -35.7  230  47 24   7.9   4.3 | -37.2 -35.0  235  47 24   7.7   4.2
 32000 -32.9 -27.2  225  45 23   7.9   4.3 | -32.6 -26.7  225  46 23   7.6   4.2
 30000 -28.2 -18.8  225  45 23   7.8   4.3 | -28.0 -18.4  230  45 23   7.8   4.3
 29000 -25.9 -14.6  225  45 23   7.8   4.3 | -25.6 -14.1  230  45 23   7.8   4.3
 28000 -23.6 -10.5  225  46 23   7.5   4.1 | -23.3  -9.9  230  44 23   7.2   4.0
 27000 -21.4  -6.5  230  44 23   7.3   4.0 | -21.3  -6.3  235  43 22   6.8   3.8
 26000 -19.2  -2.6  230  43 22   7.3   4.0 | -19.2  -2.6  235  42 21   6.8   3.8
 25000 -17.0   1.4  235  42 22   7.4   4.0 | -17.1   1.2  240  41 21   6.9   3.8
 24000 -14.9   5.2  235  40 21   6.7   3.7 | -15.1   4.8  240  38 20   6.8   3.7
 23000 -12.9   8.8  240  37 19   6.7   3.7 | -13.0   8.6  245  36 18   6.8   3.8
 22000 -10.8  12.6  240  35 18   6.8   3.7 | -10.9  12.4  245  33 17   6.9   3.8
 21000  -9.2  15.4  240  31 16   5.4   3.0 |  -9.3  15.3  250  30 15   5.3   2.9
 20000  -7.6  18.3  240  28 14   5.5   3.0 |  -7.7  18.1  245  26 14   5.6   3.1
 19500  -6.8  19.8  240  26 13   5.5   3.0 |  -6.9  19.6  245  25 13   5.7   3.1
 19000  -6.0  21.2  240  24 13   5.0   2.7 |  -6.2  20.8  245  23 12   4.7   2.6
 18500  -5.4  22.3  245  23 12   4.8   2.6 |  -5.6  21.9  245  22 11   4.3   2.4
 18000  -4.7  23.5  245  22 12   4.8   2.6 |  -5.1  22.8  245  21 11   4.3   2.4
 17500  -3.9  25.0  245  22 11   7.3   4.0 |  -4.4  24.1  245  20 10   5.5   3.0
 17000  -2.9  26.8  245  21 11   7.2   3.9 |  -3.7  25.3  245  19 10   5.5   3.0
 16500  -1.4  29.5  245  20 10   7.3   4.0 |  -2.3  27.9  245  17  9   8.1   4.4
 16000  -0.4  31.3  250  18  9   7.4   4.1 |  -1.2  29.8  245  15  8   7.9   4.3
 15500   0.6  33.1  250  17  9   5.2   2.9 |  -0.1  31.8  245  13  7   8.2   4.5
 15000   1.2  34.2  255  15  8   4.9   2.7 |   1.1  34.0  245  12  6   8.2   4.5
 14500   1.8  35.2  255  14  7   6.0   3.3 |   2.3  36.1  245  11  5   8.0   4.4
 14000   2.9  37.2  255  12  6   7.2   4.0 |   3.5  38.3  240   9  5   7.8   4.3
 13500   4.0  39.2  255  11  6   7.3   4.0 |   4.6  40.3  240   8  4   7.8   4.3
 13000   5.1  41.2  250   9  5   7.6   4.2 |   5.7  42.3  240   7  4   7.6   4.2
 12500   6.2  43.2  240   8  4   7.6   4.2 |   6.8  44.2  235   6  3   7.7   4.2
 12000   7.3  45.1  240   6  3   7.8   4.3 |   8.0  46.4  235   5  3   8.7   4.8
 11500   8.4  47.1  245   5  2   7.8   4.3 |   9.3  48.7  230   5  2   8.7   4.8
 11000   9.5  49.1  260   4  2   7.7   4.2 |  10.5  50.9  230   4  2   7.6   4.1
 10500  10.6  51.1  275   3  1  10.6   5.8 |  11.6  52.9  240   3  1  10.1   5.6
 10250  11.5  52.7  290   3  1  12.1   6.7 |  12.4  54.3  255   2  1  11.2   6.1
 10000  12.2  54.0  290   3  1   9.4   5.1 |  13.1  55.6  270   2  1   8.6   4.7
  9750  13.0  55.4  290   3  1  10.2   5.6 |  13.7  56.7  285   2  1   9.3   5.1
  9500  13.7  56.7  290   3  1   9.8   5.4 |  14.4  57.9  300   2  1   8.9   4.9
  9250  14.4  57.9  295   3  1   8.8   4.8 |  15.0  59.0  310   3  1   8.4   4.6
  9000  15.1  59.2  295   3  1   9.4   5.1 |  15.7  60.3  310   3  1   9.3   5.1
  8750  15.8  60.4  295   3  1  10.4   5.7 |  16.4  61.5  310   3  1  10.1   5.5
  8500  16.6  61.9  295   3  1  10.1   5.6 |  17.2  63.0  315   3  2   9.9   5.4
  8250  17.4  63.3  295   3  2  10.6   5.8 |  17.9  64.2  315   3  2  11.0   6.1
  8000  18.2  64.8  295   3  2  10.2   5.6 |  18.8  65.8  315   3  2  10.3   5.7
  7750  18.9  66.0  295   3  2   9.5   5.2 |  19.5  67.1  315   3  2   9.0   4.9
  7500  19.6  67.3  295   3  2   9.8   5.4 |  20.1  68.2  315   3  2   9.7   5.3
  7250  20.3  68.5  295   3  2  10.2   5.6 |  20.9  69.6  315   4  2  10.3   5.7
  7000  21.1  70.0  295   3  2  10.2   5.6 |  21.7  71.1  315   4  2  10.3   5.6
  6750  21.8  71.2  300   3  2   9.7   5.3 |  22.4  72.3  315   4  2   9.6   5.2
  6500  22.6  72.7  300   3  2  10.3   5.7 |  23.1  73.6  315   4  2   9.7   5.3
  6250  23.4  74.1  300   3  2  11.3   6.2 |  23.9  75.0  315   4  2  10.3   5.6
  6000  24.2  75.6  300   3  2  10.5   5.7 |  24.6  76.3  315   4  2   9.8   5.4
  5750  25.0  77.0  300   3  2  12.7   6.9 |  25.4  77.7  315   4  2  10.7   5.9
  5500  26.2  79.2  300   3  2  22.4  12.3 |  26.3  79.3  315   4  2  15.1   8.3
________________________________________________________________________________

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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