Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 091303
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0703 MDT Tuesday, September 9, 2014

This forecast is for Tuesday, September 9, 2014:

If the trigger temperature of 78.6 F/25.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 67 ft/min (0.3 m/s)
   Maximum height of thermals.................. 9107 ft MSL (3822 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1415 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6223 ft MSL (938 ft AGL)
Thermal soaring outlook for Wednesday 09/10.... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 0 ft MSL (-5285 ft AGL)
Wave soaring outlook for Wednesday 09/10....... Fair

Remarks... Numerous showers today

Sunrise/Sunset.................... 06:34:57 / 19:19:20 MDT
Total possible sunshine........... 12 hr 44 min 22 sec (764 min 22 sec)
Altitude of sun at 12:56:40 MDT... 55.36 degrees

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

Freezing level.................. 14941 ft MSL (9656 ft AGL)
Convective condensation level... 14272 ft MSL (8987 ft AGL)
Lifted condensation level....... 13077 ft MSL (7792 ft AGL)
Lifted index.................... +2.1
K index......................... +29.1

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  -69.5 -93.1   270   58   30   7.5   4.1   76.3 169.3    29.6      M    M
 45000  -58.7 -73.7   275   81   42   5.7   3.1   68.6 155.5    27.0      M    M
 40000  -48.5 -55.3   275   89   46   7.7   4.2   61.8 143.3    24.4      M    M
 38000  -46.0 -50.8   275   86   44   8.2   4.5   56.9 134.5    21.6      M    M
 36000  -42.8 -45.0   270   83   43   6.6   3.6   53.1 127.6    19.5      M    M
 34000  -39.2 -38.6   265   73   38   8.3   4.5   49.9 121.8    17.6      M    M
 32000  -34.3 -29.7   260   63   32   8.4   4.6   48.8 119.8    17.2      M    M
 30000  -28.4 -19.1   255   60   31   9.1   5.0   47.9 118.3    16.9      M    M
 29000  -26.0 -14.8   260   49   25   7.7   4.2   47.3 117.2    16.7      M    M
 28000  -23.7 -10.7   260   49   25   7.7   4.2   46.4 115.5    16.1      M    M
 27000  -21.4  -6.5   260   48   25   7.7   4.3   45.6 114.0    15.6      M    M
 26000  -19.1  -2.4   260   48   25   7.8   4.3   44.9 112.8    15.2      M    M
 25000  -17.0   1.4   260   48   25   6.7   3.7   44.0 111.2    14.6      M    M
 24000  -15.1   4.8   260   46   24   6.4   3.5   42.7 108.9    13.7      M    M
 23000  -13.3   8.1   260   44   23   6.4   3.5   41.6 106.9    12.8      M    M
 22000  -11.4  11.5   255   37   19   6.3   3.5   40.3 104.6    11.9      M    M
 21000  -10.0  14.0   250   31   16   3.8   2.1   38.7 101.6    10.5      M    M
 20000   -8.9  16.0   245   24   13   3.6   2.0   36.6  97.9     8.8      M    M
 19500   -8.3  17.1   245   24   12   5.2   2.9   35.6  96.1     8.0      M    M
 19000   -7.5  18.5   245   23   12   6.3   3.5   34.9  94.8     7.4      M    M
 18500   -6.5  20.3   245   23   12   7.2   3.9   34.4  93.9     7.0      M    M
 18000   -5.5  22.1   245   23   12   7.4   4.1   34.0  93.2     6.6      M    M
 17500   -4.5  23.9   240   23   12   6.0   3.3   33.5  92.2     6.1      M    M
 17000   -3.6  25.5   240   23   12   6.0   3.3   32.8  91.1     5.6      M    M
 16500   -2.7  27.1   245   22   12   5.6   3.1   32.2  90.0     5.1      M    M
 16000   -2.0  28.4   255   22   11   5.2   2.9   31.4  88.6     4.4      M    M
 15500   -1.2  29.8   255   17    9   5.3   2.9   30.7  87.2     3.7      M    M
 15000    0.2  32.4   255   10    5   9.3   5.1   29.8  85.7     2.9      M    M
 14500    1.5  34.7   260   12    6   8.9   4.9   29.7  85.5     2.8      M    M
 14000    2.8  37.0   260   14    7   8.8   4.9   29.6  85.2     2.7      M    M
 13500    4.1  39.4   260   12    6   8.8   4.9   29.4  84.9     2.5      M    M
 13000    5.5  41.9   260   11    6   8.8   4.9   29.2  84.6     2.4      M    M
 12500    6.8  44.2   255    9    5   8.8   4.9   29.1  84.4     2.3      M    M
 12000    8.1  46.6   250    8    4   8.8   4.8   29.0  84.2     2.2      M    M
 11500    9.4  48.9   230    9    5   7.9   4.3   28.8  83.9     2.1      M    M
 11000   10.4  50.7   215   11    6   7.1   3.9   28.4  83.1     1.6      M    M
 10500   11.4  52.5   220   10    5   6.9   3.8   28.0  82.3     1.1      M    M
 10250   11.9  53.4   225    9    5   7.9   4.4   27.8  82.0     0.9      M    M
 10000   12.6  54.7   230    9    5   9.1   5.0   27.7  81.8     0.8      M    M
  9750   13.2  55.8   235   10    5   9.3   5.1   27.6  81.7     0.8      M    M
  9500   13.8  56.8   240   11    5   6.0   3.3   27.5  81.6     0.7      M    M
  9250   14.1  57.4   245   11    6   3.1   1.7   27.1  80.7     0.2      M    M
  9000   14.4  57.9   250   12    6   4.0   2.2   26.6  79.9    -0.2    259  1.3
  8750   14.6  58.3   245   12    6   3.3   1.8   26.1  79.0    -0.7    244  1.2
  8500   14.9  58.8   245   11    6   5.3   2.9   25.7  78.2    -1.2    228  1.2
  8250   15.4  59.7   240   11    6   8.7   4.8   25.5  77.9    -1.4    205  1.0
  8000   16.1  61.0   235   11    6   9.3   5.1   25.5  77.8    -1.4    177  0.9
  7750   16.8  62.2   230   11    6   9.1   5.0   25.4  77.7    -1.5    150  0.8
  7500   17.5  63.5   225   11    6   9.2   5.1   25.4  77.7    -1.5    122  0.6
  7250   18.1  64.6   225   11    6   8.9   4.9   25.3  77.6    -1.6     95  0.5
  7000   18.8  65.8   220   11    6   9.9   5.4   25.3  77.5    -1.6     67  0.3
  6750   19.5  67.1   215   12    6   6.2   3.4   25.2  77.4    -1.7     40  0.2
  6500   19.7  67.5   210   14    7   1.4   0.8   24.7  76.5    -2.2     27  0.1
  6250   19.8  67.6   205   16    8   1.7   0.9   24.1  75.4    -2.9     17  0.1
  6000   19.8  67.6   200   18    9   1.5   0.8   23.5  74.3    -3.5      7  0.0
  5750   19.9  67.8   200   12    6   2.0   1.1   22.9  73.2    -4.2      M    M
  5500   20.0  68.0   200    6    3   0.2   0.1   22.3  72.1    -4.8      M    M

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

           09/09/2014 at 0900 MDT          |       09/09/2014 at 1200 MDT
                                           |
K index... +30.5  LI... -0.5               | K index... +28.8  LI... -0.6
CAPE... +4.8  CIN... -6.4                  | CAPE... +21.3  CIN... -80.8
                                           |
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 -66.9 -88.4  275  56 29   3.9   2.2 | -66.2 -87.2  270  56 29   3.5   1.9
 45000 -59.2 -74.6  275  78 40   6.7   3.7 | -59.1 -74.4  270  79 41   6.8   3.7
 40000 -49.1 -56.4  275  82 42   6.7   3.7 | -49.0 -56.2  270  86 44   6.2   3.4
 38000 -45.1 -49.2  270  78 40   6.7   3.7 | -45.2 -49.4  265  84 43   6.2   3.4
 36000 -41.1 -42.0  265  74 38   6.7   3.7 | -41.5 -42.7  260  83 43   6.2   3.4
 34000 -36.9 -34.4  265  70 36   7.0   3.8 | -37.4 -35.3  255  75 38   7.0   3.9
 32000 -32.7 -26.9  265  66 34   7.0   3.8 | -33.1 -27.6  250  65 34   7.1   3.9
 30000 -28.5 -19.3  260  57 29   6.1   3.3 | -28.2 -18.8  245  52 27   7.5   4.1
 29000 -26.7 -16.1  255  53 27   6.1   3.4 | -26.0 -14.8  245  45 23   7.5   4.1
 28000 -24.9 -12.8  250  48 25   6.8   3.8 | -23.8 -10.8  245  39 20   7.4   4.0
 27000 -22.6  -8.7  255  46 24   7.7   4.3 | -21.7  -7.1  250  36 19   7.0   3.9
 26000 -20.3  -4.5  255  44 23   7.8   4.3 | -19.6  -3.3  250  35 18   7.1   3.9
 25000 -18.1  -0.6  255  42 22   8.1   4.4 | -17.5   0.5  255  33 17   7.1   3.9
 24000 -16.0   3.2  260  38 20   6.7   3.7 | -15.5   4.1  260  32 16   6.7   3.7
 23000 -14.1   6.6  260  33 17   6.7   3.7 | -13.6   7.5  260  30 16   6.7   3.7
 22000 -12.1  10.2  265  28 14   6.8   3.7 | -11.6  11.1  265  29 15   6.9   3.8
 21000 -10.2  13.6  270  27 14   6.4   3.5 | -10.0  14.0  270  29 15   5.2   2.9
 20000  -8.4  16.9  270  28 15   6.4   3.5 |  -8.5  16.7  275  31 16   5.2   2.9
 19500  -7.4  18.7  275  29 15   6.4   3.5 |  -7.7  18.1  275  33 17   5.2   2.9
 19000  -6.5  20.3  275  29 15   6.2   3.4 |  -7.0  19.4  275  34 17   5.5   3.0
 18500  -5.6  21.9  275  29 15   6.1   3.3 |  -6.1  21.0  280  33 17   5.8   3.2
 18000  -4.8  23.4  275  28 15   6.0   3.3 |  -5.3  22.5  275  32 16   5.9   3.2
 17500  -3.9  25.0  280  28 14   6.4   3.5 |  -4.5  23.9  280  31 16   5.4   2.9
 17000  -3.0  26.6  280  27 14   6.3   3.5 |  -3.7  25.3  280  31 16   5.4   2.9
 16500  -2.1  28.2  280  26 13   6.1   3.3 |  -2.9  26.8  280  31 16   5.5   3.0
 16000  -1.2  29.8  280  24 13   5.7   3.1 |  -2.1  28.2  280  31 16   5.6   3.1
 15500  -0.4  31.3  275  23 12   5.7   3.1 |  -0.9  30.4  280  30 15   6.9   3.8
 15000   0.9  33.6  275  21 11   6.0   3.3 |   0.3  32.5  280  29 15   7.9   4.3
 14500   1.7  35.1  270  20 10   6.1   3.3 |   1.5  34.7  285  28 15   8.0   4.4
 14000   2.6  36.7  270  18  9   6.2   3.4 |   2.7  36.9  285  28 14   8.2   4.5
 13500   3.5  38.3  265  17  9   6.2   3.4 |   3.9  39.0  285  27 14   8.2   4.5
 13000   4.4  39.9  260  15  8   6.2   3.4 |   5.0  41.0  285  26 14   7.2   4.0
 12500   5.3  41.5  255  14  7   6.2   3.4 |   6.1  43.0  285  25 13   7.4   4.1
 12000   6.3  43.3  250  13  7   7.0   3.8 |   7.1  44.8  285  24 12   7.0   3.8
 11500   7.2  45.0  245  12  6   7.0   3.8 |   8.1  46.6  285  22 11   7.0   3.9
 11000   8.2  46.8  235  11  6   6.4   3.5 |   9.1  48.4  285  20 10   6.6   3.6
 10500   9.1  48.4  230  10  5   6.4   3.5 |  10.0  50.0  280  17  9   7.0   3.8
 10250   9.6  49.3  230   9  5   8.4   4.6 |  10.6  51.1  280  16  8   9.1   5.0
 10000  10.2  50.4  225   8  4   8.0   4.4 |  11.2  52.2  275  14  7   8.3   4.6
  9750  10.7  51.3  220   6  3   6.1   3.3 |  11.7  53.1  275  13  7   6.6   3.6
  9500  11.2  52.2  215   5  3   6.7   3.7 |  12.2  54.0  270  12  6   7.1   3.9
  9250  11.6  52.9  205   4  2   6.1   3.3 |  12.7  54.9  265  11  5   6.9   3.8
  9000  12.1  53.8  200   2  1   6.1   3.4 |  13.2  55.8  260   9  5   6.3   3.4
  8750  12.6  54.7  165   1  0   6.7   3.7 |  13.6  56.5  255   8  4   5.8   3.2
  8500  13.1  55.6  070   1  1   6.3   3.5 |  14.1  57.4  245   8  4   5.8   3.2
  8250  13.7  56.7  050   3  1   7.8   4.3 |  14.5  58.1  240   7  4   6.3   3.5
  8000  14.3  57.7  030   4  2   8.6   4.7 |  15.0  59.0  225   5  3   6.5   3.5
  7750  15.0  59.0  020   5  3   7.8   4.3 |  15.4  59.7  215   4  2   5.9   3.2
  7500  15.5  59.9  015   6  3   7.7   4.2 |  15.8  60.4  195   3  1   6.1   3.3
  7250  16.1  61.0  010   7  4   6.8   3.7 |  16.4  61.5  175   2  1   9.5   5.2
  7000  16.6  61.9  010   7  4   6.0   3.3 |  17.2  63.0  175   2  1  11.2   6.2
  6750  17.0  62.6  010   7  4   5.5   3.0 |  17.9  64.2  180   2  1   8.9   4.9
  6500  17.4  63.3  015   7  4   4.4   2.4 |  18.6  65.5  185   1  1   9.4   5.1
  6250  17.6  63.7  015   6  3   3.5   1.9 |  19.4  66.9  185   1  1  11.2   6.1
  6000  17.8  64.0  015   4  2   3.4   1.9 |  20.2  68.4  190   1  1  11.6   6.3
  5750  18.0  64.4  010   2  1   6.3   3.5 |  21.0  69.8  190   1  1  10.6   5.8
  5500  18.6  65.5  310   1  0  13.6   7.5 |  21.9  71.4  190   1  0  13.8   7.6

           09/09/2014 at 1500 MDT          |       09/09/2014 at 1800 MDT
                                           |
K index... +15.6  LI... -1.4               | K index... +29.3  LI... -2.3
CAPE... +139.3  CIN... -21.5               | CAPE... +312.1  CIN... -14.6
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.6 -86.1  265  48 25   3.7   2.0 | -64.6 -84.3  270  47 24   3.0   1.6
 45000 -58.6 -73.5  265  74 38   6.1   3.4 | -58.3 -72.9  265  74 38   6.1   3.4
 40000 -49.2 -56.6  265  85 44   7.0   3.8 | -49.0 -56.2  260  86 44   6.6   3.6
 38000 -45.0 -49.0  260  84 43   7.0   3.8 | -45.0 -49.0  260  87 45   6.6   3.6
 36000 -40.9 -41.6  260  84 43   7.0   3.8 | -41.1 -42.0  260  87 45   6.7   3.7
 34000 -37.0 -34.6  260  79 41   6.4   3.5 | -37.3 -35.1  255  80 41   6.1   3.3
 32000 -33.2 -27.8  255  73 37   6.4   3.5 | -33.7 -28.7  255  70 36   6.2   3.4
 30000 -28.3 -18.9  250  60 31   7.6   4.2 | -28.3 -18.9  245  58 30   8.8   4.8
 29000 -26.0 -14.8  245  53 27   7.7   4.2 | -25.7 -14.3  240  53 27   8.9   4.9
 28000 -23.8 -10.8  240  47 24   7.7   4.2 | -23.1  -9.6  235  48 25   8.3   4.5
 27000 -21.6  -6.9  240  47 24   7.5   4.1 | -21.1  -6.0  235  46 23   6.6   3.6
 26000 -19.4  -2.9  240  46 24   7.5   4.1 | -19.1  -2.4  235  44 22   6.6   3.6
 25000 -17.2   1.0  245  46 24   7.6   4.2 | -17.2   1.0  235  42 21   6.7   3.7
 24000 -15.2   4.6  245  44 23   6.2   3.4 | -15.4   4.3  240  41 21   5.7   3.1
 23000 -13.4   7.9  245  42 22   6.2   3.4 | -13.7   7.3  255  42 22   5.7   3.1
 22000 -11.6  11.1  245  40 21   6.3   3.5 | -12.0  10.4  265  45 23   5.7   3.2
 21000  -9.8  14.4  250  40 20   5.6   3.1 | -10.4  13.3  270  44 23   5.8   3.2
 20000  -8.1  17.4  260  41 21   5.6   3.1 |  -8.7  16.3  275  42 21   5.8   3.2
 19500  -7.2  19.0  265  43 22   5.7   3.1 |  -7.8  18.0  275  40 21   5.8   3.2
 19000  -6.4  20.5  265  44 23   6.0   3.3 |  -7.0  19.4  280  39 20   5.7   3.1
 18500  -5.2  22.6  270  44 23   7.0   3.8 |  -6.2  20.8  280  38 20   5.3   2.9
 18000  -4.1  24.6  270  43 22   7.3   4.0 |  -5.5  22.1  280  38 19   5.3   2.9
 17500  -3.1  26.4  270  43 22   5.4   3.0 |  -4.7  23.5  280  37 19   4.6   2.5
 17000  -2.3  27.9  270  42 22   5.2   2.9 |  -4.1  24.6  280  35 18   4.5   2.5
 16500  -1.5  29.3  270  41 21   5.1   2.8 |  -3.4  25.9  285  34 17   4.5   2.5
 16000  -0.8  30.6  270  40 21   4.9   2.7 |  -2.8  27.0  280  33 17   4.6   2.5
 15500  -0.1  31.8  270  39 20   5.1   2.8 |  -1.8  28.8  280  31 16   4.7   2.6
 15000   1.0  33.8  270  36 18   6.0   3.3 |  -1.1  30.0  280  28 14   4.9   2.7
 14500   1.7  35.1  270  34 17   6.3   3.5 |  -0.4  31.3  275  25 13   5.3   2.9
 14000   2.5  36.5  265  31 16   6.3   3.5 |   0.7  33.3  275  22 12   8.6   4.7
 13500   3.4  38.1  265  28 14   6.3   3.4 |   1.9  35.4  270  20 10   8.3   4.6
 13000   4.3  39.7  265  25 13   8.2   4.5 |   3.2  37.8  270  18  9   9.8   5.4
 12500   5.4  41.7  265  22 11   8.2   4.5 |   4.6  40.3  265  17  9   9.7   5.3
 12000   6.5  43.7  260  20 10   7.9   4.3 |   6.0  42.8  265  16  8   9.1   5.0
 11500   7.7  45.9  260  17  9   7.9   4.3 |   7.4  45.3  265  15  8   9.2   5.0
 11000   8.8  47.8  260  15  7   8.1   4.5 |   8.7  47.7  260  14  7   8.8   4.8
 10500  10.0  50.0  260  13  7   8.7   4.8 |   9.9  49.8  255  13  7   9.8   5.4
 10250  10.7  51.3  260  12  6  10.7   5.9 |  10.8  51.4  255  12  6  12.3   6.8
 10000  11.5  52.7  265  11  6   9.7   5.3 |  11.6  52.9  255  12  6  10.7   5.9
  9750  12.1  53.8  265  10  5   8.2   4.5 |  12.3  54.1  250  11  5   8.9   4.9
  9500  12.7  54.9  265   9  5   8.7   4.8 |  13.0  55.4  245  10  5   9.5   5.2
  9250  13.3  55.9  265   9  4   8.3   4.6 |  13.6  56.5  240   9  5   9.1   5.0
  9000  13.9  57.0  265   7  4   7.9   4.4 |  14.2  57.6  240   8  4   9.1   5.0
  8750  14.5  58.1  265   7  3   7.9   4.4 |  14.9  58.8  240   7  4   9.5   5.2
  8500  15.1  59.2  260   6  3   7.7   4.2 |  15.5  59.9  240   6  3   9.0   4.9
  8250  15.7  60.3  260   5  3   8.6   4.7 |  16.2  61.2  235   5  3  10.8   5.9
  8000  16.3  61.3  250   4  2   8.3   4.5 |  17.0  62.6  240   5  3  10.6   5.8
  7750  16.8  62.2  245   3  2   7.3   4.0 |  17.7  63.9  240   5  2   8.8   4.8
  7500  17.3  63.1  235   2  1   7.2   4.0 |  18.4  65.1  245   5  2   9.2   5.0
  7250  17.9  64.2  215   2  1   9.2   5.1 |  19.1  66.4  245   5  2   9.9   5.4
  7000  18.7  65.7  210   2  1  10.7   5.9 |  19.9  67.8  250   5  2  10.3   5.6
  6750  19.4  66.9  205   2  1   9.3   5.1 |  20.6  69.1  250   4  2   9.5   5.2
  6500  20.1  68.2  205   2  1   9.5   5.2 |  21.3  70.3  255   4  2   9.7   5.3
  6250  20.8  69.4  205   2  1  10.7   5.9 |  22.0  71.6  255   4  2  10.3   5.7
  6000  21.6  70.9  205   2  1  11.5   6.3 |  22.8  73.0  260   4  2  10.6   5.8
  5750  22.5  72.5  205   2  1  10.4   5.7 |  23.6  74.5  260   4  2   9.0   4.9
  5500  23.3  73.9  200   2  1  13.6   7.5 |  24.2  75.6  265   4  2   8.3   4.6
________________________________________________________________________________

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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