Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201258
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0658 MDT Wednesday, August 20, 2014

This forecast is for Wednesday, August 20, 2014:

If the trigger temperature of 80.7 F/27.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 909 ft/min (4.6 m/s)
   Maximum height of thermals.................. 15402 ft MSL (10117 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1045 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................. 10117 ft MSL (4832 ft AGL)
Thermal soaring outlook for Thursday 08/21..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 18572 ft MSL (13287 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 rawinsonde observation taken on 08/20/2014 at 0600 MDT

Freezing level.................. 15522 ft MSL (10237 ft AGL)
Convective condensation level... 14815 ft MSL (9530 ft AGL)
Lifted condensation level....... 15084 ft MSL (9798 ft AGL)
Lifted index.................... -0.5
K index......................... +25.9

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  -65.0 -85.0   270   30   15   3.5   1.9   84.7 184.5    31.5      M    M
 45000  -62.5 -80.5   255   62   32   3.5   1.9   63.3 146.0    20.5      M    M
 40000  -52.7 -62.9   245   57   30   8.5   4.6   55.8 132.4    16.9      M    M
 38000  -48.1 -54.6   245   55   28   6.5   3.6   53.9 129.0    16.1      M    M
 36000  -44.1 -47.4   245   52   27   7.3   4.0   51.4 124.5    14.7      M    M
 34000  -39.3 -38.7   245   47   24   9.1   5.0   49.9 121.8    14.0      M    M
 32000  -34.7 -30.5   245   40   21   8.0   4.4   48.3 118.9    13.1      M    M
 30000  -29.5 -21.1   240   37   19   7.5   4.1   46.6 115.8    12.1      M    M
 29000  -27.1 -16.8   240   35   18   8.4   4.6   45.8 114.5    11.7      M    M
 28000  -24.3 -11.7   240   34   18   9.1   5.0   45.7 114.3    11.8      M    M
 27000  -21.7  -7.1   240   33   17   8.6   4.7   45.2 113.4    11.5      M    M
 26000  -19.2  -2.6   240   31   16   8.3   4.6   44.8 112.7    11.3      M    M
 25000  -17.7   0.1   240   30   15   9.1   5.0   43.1 109.6    10.0      M    M
 24000  -15.2   4.6   240   28   14  10.1   5.5   42.7 108.8     9.7      M    M
 23000  -13.8   7.2   215   27   14   2.5   1.4   40.8 105.4     8.2      M    M
 22000  -12.8   9.0   195   31   16   7.9   4.3   38.6 101.5     6.4      M    M
 21000  -10.5  13.1   200   29   15   7.8   4.3   37.9 100.2     5.7      M    M
 20000   -8.3  17.1   210   27   14   6.4   3.5   37.2  99.0     5.2      M    M
 19500   -7.7  18.1   220   28   14   3.1   1.7   36.2  97.2     4.3      M    M
 19000   -7.0  19.4   225   29   15   7.3   4.0   35.4  95.6     3.6      M    M
 18500   -5.9  21.4   230   29   15   7.8   4.3   35.0  95.0     3.2      M    M
 18000   -4.7  23.5   230   29   15   7.8   4.3   34.6  94.4     2.9      M    M
 17500   -3.6  25.5   235   29   15   8.0   4.4   34.3  93.8     2.6      M    M
 17000   -2.6  27.3   240   29   15   5.1   2.8   33.9  93.0     2.2      M    M
 16500   -2.0  28.4   240   30   15   5.6   3.1   33.0  91.5     1.4      M    M
 16000   -1.1  30.0   245   30   15   6.0   3.3   32.4  90.4     0.8      M    M
 15500   -0.2  31.6   245   29   15   6.1   3.3   31.8  89.2     0.3      M    M
 15000    1.3  34.3   250   26   13   9.9   5.4   31.0  87.9    -0.4    861  4.4
 14500    3.0  37.4   255   24   12   8.9   4.9   31.3  88.4    -0.2    795  4.0
 14000    3.9  39.0   260   22   12   6.6   3.6   30.8  87.4    -0.7    752  3.8
 13500    4.9  40.8   255   20   10   6.4   3.5   30.2  86.4    -1.3    709  3.6
 13000    5.8  42.4   255   17    9   6.5   3.6   29.7  85.4    -1.8    666  3.4
 12500    6.8  44.2   250   14    7   7.6   4.2   29.1  84.5    -2.3    623  3.2
 12000    8.1  46.6   245   12    6   8.9   4.9   29.0  84.2    -2.4    569  2.9
 11500    9.4  48.9   240   10    5   9.0   4.9   28.9  84.0    -2.6    514  2.6
 11000   10.8  51.4   230    8    4   9.0   4.9   28.7  83.7    -2.8    460  2.3
 10500   12.1  53.8   220    7    3   9.0   4.9   28.6  83.5    -2.9    405  2.1
 10250   12.7  54.9   210    6    3   8.8   4.9   28.6  83.4    -3.0    378  1.9
 10000   13.4  56.1   215    7    4   8.7   4.8   28.5  83.3    -3.1    351  1.8
  9750   14.0  57.2   220    8    4   8.7   4.8   28.4  83.1    -3.2    325  1.6
  9500   14.7  58.5   220    9    5   8.7   4.8   28.3  83.0    -3.3    298  1.5
  9250   15.3  59.5   225   10    5   8.7   4.8   28.2  82.8    -3.4    272  1.4
  9000   15.9  60.6   225   11    6   8.6   4.7   28.2  82.7    -3.5    245  1.2
  8750   16.5  61.7   220   11    6   5.8   3.2   28.0  82.4    -3.6    221  1.1
  8500   16.8  62.2   220   10    5   4.0   2.2   27.6  81.6    -4.1    205  1.0
  8250   17.1  62.8   220   10    5   4.5   2.5   27.2  80.9    -4.5    188  1.0
  8000   17.4  63.3   215   10    5   4.4   2.4   26.8  80.2    -4.9    171  0.9
  7750   17.7  63.9   225    8    4   4.4   2.4   26.3  79.4    -5.4    154  0.8
  7500   18.0  64.4   235    7    3   4.4   2.4   25.9  78.7    -5.8    138  0.7
  7250   18.4  65.1   250    5    3   4.4   2.4   25.5  77.9    -6.2    121  0.6
  7000   18.5  65.3   275    5    3  -0.0  -0.0   25.0  77.0    -6.8    108  0.6
  6750   18.1  64.6   285    5    3  -2.7  -1.5   24.1  75.3    -7.9    112  0.6
  6500   18.0  64.4   290    6    3  -1.1  -0.6   23.2  73.8    -8.8    109  0.6
  6250   18.1  64.6   295    6    3   2.9   1.6   22.5  72.5    -9.5    100  0.5
  6000   18.4  65.1   300    7    4   6.7   3.7   22.2  71.9    -9.9     82  0.4
  5750   18.8  65.8   300    5    2   3.9   2.2   21.9  71.4   -10.3     64  0.3
  5500   18.6  65.5   300    2    1  -7.6  -4.2   21.1  69.9   -11.2     61  0.3

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

           08/20/2014 at 0900 MDT          |       08/20/2014 at 1200 MDT
                                           |
K index... +28.0  LI... -1.5               | K index... +26.4  LI... -1.7
CAPE... +136.1  CIN... -125.3              | CAPE... +266.7  CIN... -28.3
                                           |
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 -64.3 -83.7  265  35 18   0.4   0.2 | -64.6 -84.3  255  34 17   0.5   0.3
 45000 -61.1 -78.0  260  59 30   5.7   3.1 | -61.1 -78.0  260  56 29   6.1   3.3
 40000 -52.3 -62.1  250  56 29   6.9   3.8 | -51.9 -61.4  250  56 29   7.0   3.8
 38000 -48.2 -54.8  250  51 26   6.9   3.8 | -47.7 -53.9  245  53 27   7.0   3.8
 36000 -44.0 -47.2  245  46 24   6.8   3.7 | -43.5 -46.3  240  50 26   6.9   3.8
 34000 -39.1 -38.4  240  42 22   8.4   4.6 | -38.8 -37.8  235  46 23   8.0   4.4
 32000 -34.1 -29.4  240  38 20   8.4   4.6 | -33.4 -28.1  230  41 21   8.0   4.4
 30000 -28.8 -19.8  235  36 19   7.7   4.2 | -28.7 -19.7  235  38 20   7.9   4.3
 29000 -26.5 -15.7  235  36 18   7.7   4.2 | -26.3 -15.3  235  37 19   7.9   4.3
 28000 -24.2 -11.6  235  35 18   7.2   4.0 | -24.0 -11.2  235  36 19   7.7   4.2
 27000 -22.1  -7.8  235  34 18   6.8   3.8 | -21.7  -7.1  235  36 18   7.6   4.2
 26000 -20.1  -4.2  235  34 17   6.9   3.8 | -19.4  -2.9  235  35 18   7.6   4.2
 25000 -18.1  -0.6  235  33 17   7.0   3.9 | -17.2   1.0  235  35 18   7.8   4.3
 24000 -16.3   2.7  235  32 17   5.9   3.2 | -15.3   4.5  235  33 17   6.2   3.4
 23000 -14.6   5.7  235  32 16   6.0   3.3 | -13.5   7.7  235  32 17   6.3   3.5
 22000 -12.9   8.8  235  31 16   6.1   3.3 | -11.7  10.9  235  31 16   6.5   3.6
 21000 -10.9  12.4  230  30 15   7.4   4.1 |  -9.8  14.4  235  29 15   6.6   3.6
 20000  -8.7  16.3  230  29 15   7.5   4.1 |  -7.9  17.8  230  27 14   6.7   3.7
 19500  -7.6  18.3  225  29 15   7.5   4.1 |  -6.9  19.6  230  26 14   6.7   3.7
 19000  -6.6  20.1  225  28 15   7.2   4.0 |  -6.0  21.2  230  25 13   6.8   3.7
 18500  -5.5  22.1  220  27 14   7.1   3.9 |  -5.0  23.0  230  24 12   6.8   3.7
 18000  -4.5  23.9  220  26 14   7.0   3.9 |  -4.0  24.8  230  23 12   6.8   3.7
 17500  -3.4  25.9  220  25 13   7.7   4.2 |  -3.0  26.6  225  22 11   6.4   3.5
 17000  -2.3  27.9  215  23 12   7.6   4.2 |  -2.1  28.2  225  20 10   6.4   3.5
 16500  -1.2  29.8  215  21 11   6.9   3.8 |  -1.1  30.0  225  19 10   5.9   3.2
 16000  -0.3  31.5  215  19 10   6.5   3.6 |  -0.3  31.5  220  17  9   5.7   3.1
 15500   1.1  34.0  220  16  8   6.6   3.6 |   0.9  33.6  220  15  8   5.9   3.2
 15000   2.1  35.8  225  14  7   6.6   3.6 |   1.7  35.1  220  13  7   6.0   3.3
 14500   3.0  37.4  240  11  6   6.6   3.6 |   2.6  36.7  220  11  6   6.5   3.5
 14000   4.0  39.2  250  11  6   6.5   3.6 |   3.6  38.5  225  10  5   7.0   3.9
 13500   4.9  40.8  260  10  5   6.5   3.6 |   4.6  40.3  230   9  5   7.1   3.9
 13000   5.8  42.4  265  10  5   6.5   3.5 |   5.7  42.3  245   8  4   7.3   4.0
 12500   6.8  44.2  270  10  5   6.5   3.5 |   6.8  44.2  255   8  4   7.3   4.0
 12000   7.8  46.0  275  10  5   7.3   4.0 |   7.9  46.2  270   9  5   8.1   4.4
 11500   8.8  47.8  275   9  5   7.3   4.0 |   9.1  48.4  280  10  5   8.2   4.5
 11000   9.8  49.6  270   9  5   6.7   3.7 |  10.1  50.2  285  12  6   6.0   3.3
 10500  10.8  51.4  270   8  4   8.8   4.8 |  11.0  51.8  285  13  7   8.3   4.6
 10250  11.6  52.9  270   8  4   9.8   5.4 |  11.6  52.9  285  13  7   8.8   4.8
 10000  12.1  53.8  270   7  4   7.2   4.0 |  12.1  53.8  290  11  6   6.3   3.4
  9750  12.7  54.9  275   7  4   7.2   4.0 |  12.6  54.7  290  10  5   7.0   3.9
  9500  13.2  55.8  275   7  3   7.4   4.1 |  13.0  55.4  290   8  4   6.7   3.7
  9250  13.7  56.7  280   6  3   6.2   3.4 |  13.5  56.3  290   7  3   7.6   4.2
  9000  14.1  57.4  285   6  3   6.0   3.3 |  14.1  57.4  295   6  3   9.2   5.0
  8750  14.6  58.3  295   5  3   7.0   3.8 |  14.7  58.5  295   5  3   9.5   5.2
  8500  15.1  59.2  300   5  3   6.7   3.7 |  15.4  59.7  300   4  2   9.5   5.2
  8250  15.6  60.1  310   5  3   7.3   4.0 |  16.1  61.0  305   4  2  10.4   5.7
  8000  16.1  61.0  320   5  3   7.5   4.1 |  16.9  62.4  305   4  2  10.1   5.6
  7750  16.6  61.9  325   6  3   7.4   4.1 |  17.6  63.7  305   4  2   9.1   5.0
  7500  17.1  62.8  330   7  3   7.5   4.1 |  18.3  64.9  310   4  2   9.7   5.3
  7250  17.7  63.9  330   7  4   7.8   4.3 |  19.0  66.2  310   4  2  10.5   5.8
  7000  18.2  64.8  335   8  4   7.3   4.0 |  19.8  67.6  310   4  2  10.5   5.8
  6750  18.7  65.7  335   9  4   5.9   3.2 |  20.6  69.1  310   3  2   9.4   5.2
  6500  19.1  66.4  330   9  5   4.5   2.5 |  21.3  70.3  310   3  2  10.0   5.5
  6250  19.4  66.9  335   8  4   3.9   2.2 |  22.1  71.8  310   3  2  11.3   6.2
  6000  19.6  67.3  340   6  3   3.7   2.0 |  22.9  73.2  310   3  2  10.5   5.8
  5750  19.8  67.6  350   4  2   6.2   3.4 |  23.7  74.7  310   3  2  12.3   6.8
  5500  20.5  68.9  350   2  1  14.4   7.9 |  24.9  76.8  310   3  2  21.2  11.6

           08/20/2014 at 1500 MDT          |       08/20/2014 at 1800 MDT
                                           |
K index... +29.7  LI... -1.7               | K index... +33.4  LI... -1.8
CAPE... +321.4  CIN... -9.1                | CAPE... +333.9  CIN... -19.4
                                           |
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 -64.8 -84.6  250  38 19   0.5   0.3 | -64.5 -84.1  250  34 18   0.2   0.1
 45000 -61.3 -78.3  255  54 28   6.3   3.5 | -61.2 -78.2  250  53 27   6.5   3.6
 40000 -51.6 -60.9  245  53 27   7.1   3.9 | -51.4 -60.5  240  54 28   7.0   3.8
 38000 -47.4 -53.3  245  51 26   7.1   3.9 | -47.1 -52.8  240  52 27   7.0   3.8
 36000 -43.1 -45.6  240  50 26   7.1   3.9 | -42.9 -45.2  240  51 26   6.9   3.8
 34000 -38.4 -37.1  235  47 24   7.8   4.3 | -37.5 -35.5  235  48 25   8.2   4.5
 32000 -33.2 -27.8  225  43 22   7.9   4.3 | -32.6 -26.7  230  46 23   8.5   4.7
 30000 -28.4 -19.1  225  41 21   8.0   4.4 | -27.9 -18.2  225  44 23   7.8   4.3
 29000 -26.0 -14.8  230  40 20   8.0   4.4 | -25.5 -13.9  230  43 22   7.8   4.3
 28000 -23.6 -10.5  230  38 20   7.7   4.2 | -23.2  -9.8  230  42 22   7.1   3.9
 27000 -21.3  -6.3  230  37 19   7.6   4.2 | -21.2  -6.2  230  40 21   6.7   3.7
 26000 -19.1  -2.4  235  36 18   7.6   4.2 | -19.2  -2.6  235  39 20   6.7   3.7
 25000 -16.8   1.8  240  35 18   7.7   4.2 | -17.2   1.0  240  38 19   6.7   3.7
 24000 -14.8   5.4  240  33 17   6.7   3.7 | -15.2   4.6  245  36 18   6.6   3.6
 23000 -12.8   9.0  240  30 16   6.7   3.7 | -13.3   8.1  245  34 17   6.6   3.6
 22000 -10.8  12.6  245  28 14   6.7   3.7 | -11.3  11.7  245  32 17   6.6   3.6
 21000  -9.0  15.8  245  27 14   6.0   3.3 |  -9.4  15.1  245  30 15   6.5   3.5
 20000  -7.3  18.9  245  26 13   6.1   3.3 |  -7.5  18.5  245  27 14   6.5   3.6
 19500  -6.5  20.3  240  26 13   6.2   3.4 |  -6.5  20.3  245  26 13   6.5   3.6
 19000  -5.6  21.9  240  25 13   6.3   3.5 |  -5.7  21.7  245  25 13   4.6   2.5
 18500  -4.7  23.5  245  24 12   6.4   3.5 |  -5.2  22.6  245  24 12   3.9   2.2
 18000  -3.8  25.2  245  23 12   6.4   3.5 |  -4.7  23.5  240  23 12   4.0   2.2
 17500  -2.8  27.0  245  21 11   6.7   3.7 |  -4.1  24.6  240  22 11   5.2   2.9
 17000  -1.9  28.6  245  20 10   6.7   3.7 |  -3.4  25.9  235  21 11   5.3   2.9
 16500  -0.6  30.9  245  18  9   5.1   2.8 |  -2.1  28.2  230  20 10   9.4   5.1
 16000   0.1  32.2  245  17  9   5.2   2.9 |  -0.8  30.6  230  18  9   9.2   5.1
 15500   0.8  33.4  245  16  8   6.0   3.3 |   0.5  32.9  225  17  9   8.4   4.6
 15000   1.7  35.1  245  14  7   6.1   3.4 |   1.6  34.9  225  16  8   8.3   4.5
 14500   2.6  36.7  245  13  7   6.8   3.7 |   2.8  37.0  220  14  7   7.8   4.3
 14000   3.7  38.7  245  11  6   7.4   4.1 |   3.9  39.0  220  13  7   7.4   4.1
 13500   4.8  40.6  240  10  5   7.5   4.1 |   5.0  41.0  220  12  6   7.5   4.1
 13000   5.9  42.6  245   8  4   7.7   4.2 |   6.2  43.2  215  10  5   8.0   4.4
 12500   7.0  44.6  245   7  3   7.7   4.2 |   7.4  45.3  215   9  4   8.1   4.4
 12000   8.1  46.6  255   5  3   7.9   4.4 |   8.6  47.5  210   7  4   8.8   4.8
 11500   9.3  48.7  270   4  2   8.0   4.4 |   9.9  49.8  210   6  3   8.8   4.8
 11000  10.3  50.5  285   3  2   7.1   3.9 |  11.1  52.0  210   5  2   7.2   3.9
 10500  11.3  52.3  305   3  1  10.0   5.5 |  12.1  53.8  215   3  2  10.2   5.6
 10250  12.1  53.8  310   2  1  11.7   6.4 |  13.0  55.4  220   2  1  11.1   6.1
 10000  12.8  55.0  310   3  1   9.2   5.1 |  13.6  56.5  230   2  1   7.9   4.3
  9750  13.5  56.3  315   3  1   9.9   5.4 |  14.2  57.6  250   2  1   8.8   4.8
  9500  14.2  57.6  315   3  1   9.6   5.3 |  14.8  58.6  270   2  1   8.4   4.6
  9250  14.9  58.8  315   3  1   9.4   5.2 |  15.5  59.9  290   2  1   8.5   4.7
  9000  15.6  60.1  315   3  2   9.8   5.4 |  16.1  61.0  295   2  1   9.5   5.2
  8750  16.4  61.5  315   3  2  10.2   5.6 |  16.9  62.4  295   2  1  10.1   5.6
  8500  17.1  62.8  315   3  2  10.1   5.5 |  17.6  63.7  300   2  1  10.0   5.5
  8250  17.9  64.2  315   3  2  11.2   6.1 |  18.4  65.1  305   2  1  10.6   5.8
  8000  18.8  65.8  315   3  2  10.3   5.7 |  19.1  66.4  305   2  1  10.2   5.6
  7750  19.4  66.9  315   3  2   8.9   4.9 |  19.9  67.8  305   3  1   9.4   5.2
  7500  20.1  68.2  315   3  2   9.6   5.3 |  20.6  69.1  305   3  1   9.7   5.3
  7250  20.9  69.6  315   3  2  10.3   5.7 |  21.3  70.3  305   3  2   9.9   5.4
  7000  21.7  71.1  315   3  2  10.4   5.7 |  22.0  71.6  305   3  2   9.9   5.5
  6750  22.4  72.3  310   3  2   9.7   5.3 |  22.8  73.0  305   3  2   9.8   5.4
  6500  23.1  73.6  315   3  2  10.2   5.6 |  23.5  74.3  305   3  2  10.0   5.5
  6250  23.9  75.0  310   3  2  11.2   6.1 |  24.3  75.7  305   3  2  10.4   5.7
  6000  24.8  76.6  310   3  2  10.6   5.8 |  25.1  77.2  305   4  2  10.2   5.6
  5750  25.6  78.1  310   3  2  12.0   6.6 |  25.8  78.4  305   4  2   9.9   5.4
  5500  26.7  80.1  310   3  2  20.3  11.1 |  26.6  79.9  305   4  2  11.6   6.3
________________________________________________________________________________

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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