Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 261145
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0545 MDT Tuesday, August 26, 2014

This forecast is for Tuesday, August 26, 2014:

If the trigger temperature of 75.9 F/24.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 579 ft/min (2.9 m/s)
   Maximum height of thermals.................. 10681 ft MSL (5394 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1130 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................. 8698 ft MSL (3411 ft AGL)
Thermal soaring outlook for Wednesday 08/27.... Good

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 PVA
Potential height of wave....................... 14386 ft MSL (9099 ft AGL)
Wave soaring outlook for Wednesday 08/27....... Poor

Remarks...

Sunrise/Sunset.................... 06:21:53 / 19:41:12 MDT
Total possible sunshine........... 13 hr 19 min 19 sec (799 min 19 sec)
Altitude of sun at 13:01:08 MDT... 60.46 degrees

Upper air data from numerical model forecast valid on 08/26/2014 at 0600 MDT

Freezing level.................. 15385 ft MSL (10098 ft AGL)
Convective condensation level... 12193 ft MSL (6906 ft AGL)
Lifted condensation level....... 11519 ft MSL (6232 ft AGL)
Lifted index.................... -5.6
K index......................... +25.8

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  -63.9 -83.0   245   40   20  -0.4  -0.2      M     M       M      M    M
 45000  -62.3 -80.1   245   56   29   4.5   2.5      M     M       M      M    M
 40000  -54.9 -66.8   245   55   28   8.3   4.5      M     M       M      M    M
 38000  -49.9 -57.8   245   52   27   8.4   4.6      M     M       M      M    M
 36000  -44.8 -48.6   240   49   25   8.4   4.6      M     M       M      M    M
 34000  -40.2 -40.4   240   46   24   7.5   4.1      M     M       M      M    M
 32000  -35.7 -32.3   235   43   22   7.4   4.1      M     M       M      M    M
 30000  -30.5 -22.9   235   39   20   7.8   4.3   45.4 113.7    14.2      M    M
 29000  -28.2 -18.8   235   38   19   7.8   4.3   44.6 112.4    13.8      M    M
 28000  -26.0 -14.8   235   36   18   6.9   3.8   44.0 111.1    13.4      M    M
 27000  -24.0 -11.2   235   34   18   6.7   3.6   42.6 108.8    12.5      M    M
 26000  -22.0  -7.6   230   33   17   6.7   3.7   41.5 106.7    11.7      M    M
 25000  -20.0  -4.0   230   32   16   6.6   3.6   40.4 104.8    11.0      M    M
 24000  -18.2  -0.8   230   30   15   6.3   3.4   39.1 102.4    10.0      M    M
 23000  -16.3   2.7   235   28   14   6.3   3.5   37.8 100.1     9.0      M    M
 22000  -14.5   5.9   235   26   13   6.3   3.5   36.7  98.0     8.1      M    M
 21000  -12.6   9.3   235   24   13   6.4   3.5   35.4  95.7     7.1      M    M
 20000  -10.7  12.7   235   23   12   6.5   3.5   34.3  93.7     6.1      M    M
 19500   -9.7  14.5   235   23   12   6.3   3.5   33.7  92.7     5.7      M    M
 19000   -8.7  16.3   230   21   11   8.1   4.4   33.3  91.9     5.3      M    M
 18500   -7.5  18.5   230   20   10   8.0   4.4   33.0  91.4     5.0      M    M
 18000   -6.4  20.5   230   19   10   7.8   4.3   32.7  90.8     4.8      M    M
 17500   -5.3  22.5   230   17    9   7.4   4.1   32.3  90.1     4.4      M    M
 17000   -4.2  24.4   230   15    8   7.3   4.0   31.9  89.4     4.1      M    M
 16500   -3.0  26.6   230   14    7   8.3   4.6   31.6  88.8     3.8      M    M
 16000   -1.8  28.8   235   13    7   8.2   4.5   31.3  88.3     3.6      M    M
 15500   -0.6  30.9   240   12    6   8.6   4.7   31.1  87.9     3.4      M    M
 15000    1.3  34.3   245   12    6   8.8   4.8   30.8  87.5     3.2      M    M
 14500    2.6  36.7   250   12    6   8.4   4.6   30.6  87.2     3.0      M    M
 14000    3.8  38.8   255   13    7   8.4   4.6   30.4  86.7     2.8      M    M
 13500    5.1  41.2   255   14    7   7.9   4.3   30.2  86.3     2.5      M    M
 13000    6.2  43.2   255   15    8   7.7   4.2   29.8  85.7     2.2      M    M
 12500    7.3  45.1   250   15    8   7.7   4.2   29.5  85.1     1.9      M    M
 12000    8.4  47.1   245   15    8   7.7   4.2   29.2  84.5     1.5      M    M
 11500    9.4  48.9   245   15    8   7.0   3.8   28.9  83.9     1.1      M    M
 11000   10.2  50.4   240   13    7   5.6   3.1   28.2  82.8     0.4      M    M
 10500   10.9  51.6   235   11    6   3.1   1.7   27.6  81.7    -0.3    362  1.8
 10250   11.0  51.8   230   11    6   2.8   1.5   27.0  80.6    -1.0    352  1.8
 10000   11.3  52.3   230   10    5   7.2   4.0   26.7  80.0    -1.4    334  1.7
  9750   11.8  53.2   225    8    4   7.4   4.0   26.5  79.6    -1.6    313  1.6
  9500   12.2  54.0   220    7    4   6.5   3.6   26.3  79.3    -1.9    292  1.5
  9250   12.6  54.7   215    6    3   5.4   3.0   25.9  78.7    -2.3    274  1.4
  9000   13.0  55.4   215    6    3   5.7   3.1   25.6  78.1    -2.6    255  1.3
  8750   13.4  56.1   220    6    3   6.4   3.5   25.3  77.6    -3.0    235  1.2
  8500   13.8  56.8   220    5    3   4.2   2.3   25.0  77.1    -3.3    216  1.1
  8250   14.0  57.2   225    6    3   2.3   1.3   24.5  76.1    -3.9    204  1.0
  8000   14.1  57.4   225    7    4   2.6   1.5   23.9  75.1    -4.4    192  1.0
  7750   14.2  57.6   220    8    4   1.6   0.9   23.4  74.0    -5.1    181  0.9
  7500   14.2  57.6   210    9    4  -0.8  -0.4   22.7  72.8    -5.8    174  0.9
  7250   14.1  57.4   195   10    5  -1.6  -0.9   21.8  71.2    -6.7    171  0.9
  7000   13.9  57.0   180   11    6  -2.8  -1.5   20.9  69.7    -7.6    168  0.9
  6750   13.7  56.7   170   13    7   0.4   0.2   20.0  68.0    -8.6    167  0.9
  6500   14.0  57.2   170   13    6   6.3   3.4   19.6  67.2    -9.0    151  0.8
  6250   14.5  58.1   165   12    6   7.5   4.1   19.3  66.8    -9.3    129  0.7
  6000   15.0  59.0   160   11    5   4.9   2.7   19.1  66.4    -9.6    107  0.5
  5750   15.1  59.2   155    8    4   0.2   0.1   18.6  65.4   -10.2     96  0.5
  5500   15.0  59.0   150    5    3  -0.2  -0.1   17.9  64.1   -10.9     91  0.5

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

           08/26/2014 at 0900 MDT          |       08/26/2014 at 1200 MDT
                                           |
K index... +26.4  LI... -3.6               | K index... +26.0  LI... -5.4
CAPE... +527.8  CIN... -212.3              | CAPE... +1284.4  CIN... -76.8
                                           |
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 -63.4 -82.1  245  34 18  -0.2  -0.1 | -62.7 -80.9  240  31 16  -0.8  -0.5
 45000 -61.6 -78.9  240  53 28   4.3   2.4 | -61.5 -78.7  235  54 28   4.5   2.5
 40000 -54.5 -66.1  245  52 27   7.5   4.1 | -54.2 -65.6  235  55 28   7.6   4.2
 38000 -50.0 -58.0  240  48 25   7.5   4.1 | -49.6 -57.3  235  53 27   7.7   4.2
 36000 -45.5 -49.9  235  44 23   7.5   4.1 | -45.0 -49.0  240  52 27   7.8   4.3
 34000 -40.9 -41.6  235  44 23   7.6   4.2 | -40.7 -41.3  235  50 26   7.1   3.9
 32000 -36.3 -33.3  230  44 23   7.5   4.1 | -36.4 -33.5  235  49 25   7.0   3.8
 30000 -31.0 -23.8  230  39 20   8.1   4.5 | -31.1 -24.0  230  45 23   8.2   4.5
 29000 -28.5 -19.3  230  36 18   8.1   4.5 | -28.6 -19.5  230  43 22   8.2   4.5
 28000 -26.2 -15.2  230  33 17   6.4   3.5 | -26.2 -15.2  230  41 21   7.0   3.8
 27000 -24.4 -11.9  230  33 17   6.2   3.4 | -24.2 -11.6  235  39 20   6.8   3.8
 26000 -22.6  -8.7  230  33 17   6.2   3.4 | -22.2  -8.0  235  37 19   6.9   3.8
 25000 -20.7  -5.3  230  33 17   6.3   3.4 | -20.2  -4.4  235  35 18   6.8   3.7
 24000 -18.8  -1.8  230  31 16   6.6   3.6 | -18.3  -0.9  235  33 17   6.4   3.5
 23000 -16.9   1.6  230  29 15   6.6   3.6 | -16.4   2.5  235  33 17   6.4   3.5
 22000 -15.0   5.0  230  27 14   6.7   3.7 | -14.5   5.9  235  32 16   6.5   3.6
 21000 -13.0   8.6  235  26 13   6.9   3.8 | -12.5   9.5  235  28 14   6.8   3.7
 20000 -10.9  12.4  235  24 13   6.9   3.8 | -10.5  13.1  230  24 12   6.8   3.7
 19500  -9.9  14.2  235  24 12   6.8   3.7 |  -9.5  14.9  230  22 11   6.9   3.8
 19000  -8.8  16.2  235  23 12   8.6   4.7 |  -8.5  16.7  230  20 10   6.6   3.6
 18500  -7.6  18.3  235  23 12   8.4   4.6 |  -7.6  18.3  230  17  9   6.6   3.6
 18000  -6.3  20.7  240  22 11   8.3   4.5 |  -6.6  20.1  235  15  8   7.1   3.9
 17500  -5.1  22.8  240  21 11   8.1   4.5 |  -5.5  22.1  235  14  7   7.6   4.2
 17000  -3.9  25.0  240  19 10   8.1   4.4 |  -4.4  24.1  240  12  6   7.6   4.2
 16500  -2.7  27.1  245  18  9   8.0   4.4 |  -3.2  26.2  245  11  5   8.0   4.4
 16000  -1.5  29.3  245  16  8   8.0   4.4 |  -2.1  28.2  245  10  5   7.9   4.4
 15500  -0.4  31.3  250  14  7   7.9   4.3 |  -0.4  31.3  255   8  4   7.9   4.3
 15000   1.3  34.3  255  12  6   7.8   4.3 |   0.8  33.4  255   8  4   7.7   4.2
 14500   2.5  36.5  260  11  6   8.3   4.5 |   2.0  35.6  260   8  4   9.1   5.0
 14000   3.7  38.7  265  11  5   8.2   4.5 |   3.4  38.1  265   7  4   9.1   5.0
 13500   4.9  40.8  270  10  5   8.6   4.7 |   4.7  40.5  270   7  4   8.7   4.8
 13000   6.2  43.2  275  10  5   8.7   4.8 |   5.9  42.6  275   7  3   8.7   4.8
 12500   7.5  45.5  280  10  5   8.5   4.7 |   7.2  45.0  280   6  3   9.0   4.9
 12000   8.7  47.7  280   9  5   8.4   4.6 |   8.6  47.5  280   5  3   9.1   5.0
 11500   9.9  49.8  280   9  5   8.3   4.5 |   9.9  49.8  285   5  2   8.7   4.8
 11000  11.0  51.8  275   8  4   7.8   4.3 |  11.1  52.0  285   5  2   8.0   4.4
 10500  12.2  54.0  270   8  4   3.5   1.9 |  12.3  54.1  290   5  2   3.7   2.0
 10250  12.2  54.0  270   7  4   2.7   1.5 |  12.4  54.3  290   5  2   4.6   2.5
 10000  12.7  54.9  265   7  3   8.7   4.8 |  13.1  55.6  285   5  2  11.0   6.0
  9750  13.3  55.9  260   6  3   8.8   4.8 |  13.8  56.8  285   5  2   9.9   5.4
  9500  13.9  57.0  255   6  3   5.7   3.1 |  14.5  58.1  285   5  2   7.5   4.1
  9250  14.0  57.2  250   5  3   2.4   1.3 |  14.9  58.8  280   5  2   4.9   2.7
  9000  14.3  57.7  245   5  3   5.1   2.8 |  15.3  59.5  280   5  2   6.8   3.7
  8750  14.7  58.5  235   5  3   6.4   3.5 |  15.8  60.4  275   5  2   7.3   4.0
  8500  15.0  59.0  230   5  2   4.1   2.2 |  16.2  61.2  275   4  2   5.5   3.0
  8250  15.2  59.4  235   5  3   2.8   1.5 |  16.5  61.7  270   4  2   4.7   2.6
  8000  15.3  59.5  240   5  3   2.6   1.4 |  16.9  62.4  270   4  2   3.9   2.2
  7750  15.4  59.7  240   5  3   0.9   0.5 |  17.0  62.6  270   3  2   2.7   1.5
  7500  15.4  59.7  240   5  3  -1.0  -0.5 |  17.2  63.0  285   2  1   3.3   1.8
  7250  15.2  59.4  230   5  2  -1.4  -0.8 |  17.3  63.1  335   2  1   3.6   2.0
  7000  15.1  59.2  220   5  2  -2.0  -1.1 |  17.4  63.3  015   3  1   4.0   2.2
  6750  14.9  58.8  205   5  2   1.0   0.6 |  17.6  63.7  025   4  2   7.8   4.3
  6500  15.1  59.2  195   4  2   4.9   2.7 |  18.3  64.9  025   4  2  10.8   5.9
  6250  15.4  59.7  190   3  2   4.1   2.3 |  19.1  66.4  025   4  2   9.8   5.4
  6000  15.7  60.3  180   3  1   5.9   3.2 |  19.9  67.8  025   4  2  11.9   6.5
  5750  16.3  61.3  170   3  1  11.7   6.4 |  20.9  69.6  020   4  2  17.7   9.7
  5500  17.3  63.1  165   2  1  16.3   8.9 |  22.4  72.3  020   4  2  21.3  11.7

           08/26/2014 at 1500 MDT          |       08/26/2014 at 1800 MDT
                                           |
K index... +23.2  LI... -6.6               | K index... +35.0  LI... -5.7
CAPE... +1908.6  CIN... -9.6               | CAPE... +1414.4  CIN... -0.0
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.7 -80.9  235  35 18  -0.9  -0.5 | -63.1 -81.6  240  34 18  -0.5  -0.3
 45000 -61.5 -78.7  235  59 30   4.5   2.5 | -61.8 -79.2  235  57 30   4.0   2.2
 40000 -54.3 -65.7  235  67 34   7.1   3.9 | -54.9 -66.8  230  55 28   8.9   4.9
 38000 -50.0 -58.0  230  68 35   7.2   4.0 | -49.6 -57.3  225  53 27   9.0   4.9
 36000 -45.6 -50.1  230  69 36   7.1   3.9 | -44.2 -47.6  220  51 26   9.0   4.9
 34000 -40.5 -40.9  230  66 34   8.8   4.8 | -39.0 -38.2  220  47 24   8.6   4.7
 32000 -34.5 -30.1  230  61 31   9.4   5.2 | -33.2 -27.8  220  42 22   9.4   5.1
 30000 -29.9 -21.8  230  54 28   7.6   4.2 | -28.6 -19.5  215  35 18   7.6   4.2
 29000 -27.6 -17.7  230  51 26   7.7   4.2 | -26.3 -15.3  210  32 17   7.6   4.2
 28000 -25.4 -13.7  235  48 25   6.8   3.7 | -24.1 -11.4  210  29 15   6.8   3.7
 27000 -23.4 -10.1  235  44 23   6.7   3.7 | -22.2  -8.0  210  26 13   6.7   3.7
 26000 -21.4  -6.5  235  40 21   6.7   3.7 | -20.2  -4.4  205  23 12   6.7   3.7
 25000 -19.4  -2.9  240  37 19   6.7   3.7 | -18.2  -0.8  205  19 10   6.6   3.6
 24000 -17.5   0.5  240  33 17   6.4   3.5 | -16.4   2.5  200  15  8   5.9   3.2
 23000 -15.6   3.9  240  29 15   6.4   3.5 | -14.7   5.5  195  11  6   5.9   3.3
 22000 -13.7   7.3  240  25 13   6.3   3.5 | -13.0   8.6  185   7  4   5.8   3.2
 21000 -11.9  10.6  240  23 12   6.2   3.4 | -11.4  11.5  155   6  3   5.5   3.0
 20000 -10.0  14.0  240  20 11   6.2   3.4 |  -9.8  14.4  125   6  3   5.5   3.0
 19500  -9.1  15.6  240  19 10   6.1   3.3 |  -9.0  15.8  110   7  4   5.5   3.0
 19000  -8.1  17.4  240  18  9   7.3   4.0 |  -8.1  17.4  100   8  4   5.9   3.2
 18500  -7.1  19.2  235  16  8   7.3   4.0 |  -7.3  18.9  095   9  5   5.9   3.2
 18000  -6.1  21.0  235  15  8   7.2   4.0 |  -6.4  20.5  095  10  5   6.0   3.3
 17500  -5.1  22.8  235  13  7   7.0   3.8 |  -5.6  21.9  095  11  6   6.1   3.3
 17000  -4.0  24.8  230  11  6   6.9   3.8 |  -4.7  23.5  095  12  6   6.1   3.3
 16500  -2.9  26.8  225   9  5   7.6   4.1 |  -3.8  25.2  095  12  6   6.2   3.4
 16000  -1.3  29.7  215   7  4   7.5   4.1 |  -2.5  27.5  100  13  6   6.2   3.4
 15500  -0.2  31.6  200   6  3   8.1   4.4 |  -1.6  29.1  100  12  6   6.6   3.6
 15000   1.0  33.8  190   5  3   8.1   4.4 |  -0.6  30.9  100  11  6   6.4   3.5
 14500   2.2  36.0  180   4  2   8.2   4.5 |   0.4  32.7  100  11  5   7.9   4.3
 14000   3.4  38.1  170   4  2   8.2   4.5 |   1.5  34.7  100  10  5   8.0   4.4
 13500   4.6  40.3  160   3  2   8.4   4.6 |   2.7  36.9  100   9  4   7.8   4.3
 13000   5.8  42.4  145   3  1   8.5   4.7 |   3.7  38.7  100   8  4   7.7   4.2
 12500   7.1  44.8  125   2  1   9.0   4.9 |   4.8  40.6  100   7  3   8.0   4.4
 12000   8.5  47.3  100   2  1   9.3   5.1 |   5.9  42.6  105   6  3   8.3   4.6
 11500   9.8  49.6  075   2  1   8.8   4.8 |   7.1  44.8  110   5  3   8.6   4.7
 11000  11.1  52.0  045   3  1   7.9   4.3 |   8.3  46.9  110   5  2   8.6   4.7
 10500  12.3  54.1  030   3  2   3.9   2.1 |   9.6  49.3  115   4  2   4.1   2.2
 10250  12.4  54.3  025   4  2   5.0   2.7 |   9.7  49.5  115   4  2   6.4   3.5
 10000  13.1  55.6  020   4  2  11.1   6.1 |  10.7  51.3  120   4  2  14.2   7.8
  9750  13.8  56.8  020   4  2  10.0   5.5 |  11.6  52.9  120   4  2  12.8   7.0
  9500  14.6  58.3  015   5  2   8.3   4.5 |  12.5  54.5  120   4  2  10.3   5.7
  9250  15.0  59.0  015   5  2   6.3   3.5 |  13.1  55.6  120   4  2   7.8   4.3
  9000  15.5  59.9  020   5  2   8.0   4.4 |  13.8  56.8  120   4  2  10.8   5.9
  8750  15.9  60.6  030   5  3   8.6   4.7 |  14.6  58.3  125   4  2  11.6   6.4
  8500  16.4  61.5  040   5  3   8.3   4.6 |  15.4  59.7  125   3  2  10.0   5.5
  8250  16.8  62.2  045   6  3   8.0   4.4 |  16.1  61.0  125   3  2   8.7   4.8
  8000  17.2  63.0  055   7  3   9.1   5.0 |  16.8  62.2  120   3  2   9.8   5.4
  7750  17.9  64.2  055   7  4  10.0   5.5 |  17.6  63.7  120   3  2  10.6   5.8
  7500  18.6  65.5  055   7  4   9.9   5.4 |  18.3  64.9  120   3  2  10.4   5.7
  7250  19.3  66.7  055   7  4   9.9   5.4 |  19.1  66.4  120   3  2  10.4   5.7
  7000  20.0  68.0  055   7  4   9.8   5.4 |  19.9  67.8  120   3  2  10.1   5.5
  6750  20.8  69.4  055   7  4  10.4   5.7 |  20.6  69.1  120   3  2   9.5   5.2
  6500  21.6  70.9  055   7  4  10.9   6.0 |  21.3  70.3  120   3  2   9.8   5.3
  6250  22.4  72.3  055   7  4  11.4   6.3 |  22.0  71.6  120   3  2   9.3   5.1
  6000  23.2  73.8  055   7  4   9.6   5.3 |  22.8  73.0  125   3  1  11.1   6.1
  5750  24.0  75.2  055   7  4  14.9   8.1 |  23.7  74.7  125   3  1  13.1   7.2
  5500  25.6  78.1  050   7  4  28.6  15.7 |  24.5  76.1  125   2  1  11.1   6.1
________________________________________________________________________________

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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