Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260126
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1926 MDT Monday, August 25, 2014

This forecast is for Tuesday, August 26, 2014:

If the trigger temperature of 77.8 F/25.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 578 ft/min (2.9 m/s)
   Maximum height of thermals.................. 10419 ft MSL (5132 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1200 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................. 8411 ft MSL (3124 ft AGL)
Thermal soaring outlook for Wednesday 08/27.... Poor

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....................... 17088 ft MSL (11801 ft AGL)
Wave soaring outlook for Wednesday 08/27....... Poor

Remarks... None

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.................. 14983 ft MSL (9696 ft AGL)
Convective condensation level... 11991 ft MSL (6704 ft AGL)
Lifted condensation level....... 11588 ft MSL (6301 ft AGL)
Lifted index.................... -5.2
K index......................... +29.6

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  -64.2 -83.6   250   44   23   0.6   0.3      M     M       M      M    M
 45000  -62.1 -79.8   250   57   30   4.0   2.2      M     M       M      M    M
 40000  -55.2 -67.4   240   57   30   7.9   4.3      M     M       M      M    M
 38000  -50.4 -58.7   240   55   28   8.0   4.4      M     M       M      M    M
 36000  -45.6 -50.1   240   52   27   8.0   4.4      M     M       M      M    M
 34000  -41.0 -41.8   240   49   25   7.7   4.2      M     M       M      M    M
 32000  -36.4 -33.5   235   45   23   7.5   4.1      M     M       M      M    M
 30000  -31.6 -24.9   235   41   21   8.2   4.5   44.9 112.8    13.8      M    M
 29000  -28.6 -19.5   230   38   20   8.2   4.5   44.2 111.6    13.4      M    M
 28000  -26.2 -15.2   230   36   19   7.5   4.1   43.7 110.6    13.1      M    M
 27000  -24.0 -11.2   230   34   18   7.3   4.0   42.6 108.7    12.4      M    M
 26000  -21.8  -7.2   230   32   17   7.4   4.0   41.7 107.1    11.8      M    M
 25000  -19.7  -3.5   230   30   16   7.1   3.9   40.9 105.7    11.3      M    M
 24000  -17.9  -0.2   230   28   15   5.9   3.3   39.5 103.1    10.2      M    M
 23000  -16.1   3.0   235   27   14   6.0   3.3   38.1 100.6     9.2      M    M
 22000  -14.4   6.1   235   25   13   6.2   3.4   36.9  98.3     8.2      M    M
 21000  -12.3   9.9   240   25   13   6.8   3.8   35.7  96.3     7.3      M    M
 20000  -10.3  13.5   240   25   13   6.8   3.7   34.7  94.4     6.5      M    M
 19500   -9.3  15.3   245   26   13   6.8   3.7   34.2  93.6     6.1      M    M
 19000   -8.2  17.2   245   25   13   7.4   4.1   33.8  92.8     5.8      M    M
 18500   -7.2  19.0   245   23   12   7.4   4.1   33.4  92.1     5.4      M    M
 18000   -6.1  21.0   245   21   11   7.1   3.9   33.0  91.4     5.1      M    M
 17500   -5.2  22.6   250   19   10   6.6   3.6   32.4  90.4     4.6      M    M
 17000   -4.2  24.4   250   16    8   6.7   3.7   31.9  89.4     4.0      M    M
 16500   -3.3  26.1   255   13    7   6.2   3.4   31.4  88.4     3.5      M    M
 16000   -2.4  27.7   255   11    6   6.3   3.4   30.8  87.4     2.9      M    M
 15500   -1.5  29.3   265    9    5   7.5   4.1   30.2  86.4     2.4      M    M
 15000   -0.3  31.5   270    9    5   8.0   4.4   29.9  85.9     2.2      M    M
 14500    1.5  34.7   280    9    5   8.6   4.7   29.6  85.2     1.8      M    M
 14000    2.8  37.0   280   10    5   8.7   4.7   29.4  84.9     1.6      M    M
 13500    4.0  39.2   280   10    5   8.8   4.8   29.2  84.6     1.5      M    M
 13000    5.3  41.5   280   10    5   8.9   4.9   29.1  84.3     1.3      M    M
 12500    6.6  43.9   275   11    6   8.9   4.9   29.0  84.1     1.2      M    M
 12000    7.9  46.2   270   11    5   8.8   4.8   28.8  83.8     1.0      M    M
 11500    9.2  48.6   265   11    5   8.3   4.6   28.7  83.6     0.8      M    M
 11000   10.3  50.5   260   10    5   7.4   4.1   28.3  83.0     0.4      M    M
 10500   11.3  52.3   250    9    4   4.1   2.3   28.0  82.4     0.1      M    M
 10250   11.5  52.7   250    8    4   4.4   2.4   27.4  81.3    -0.5    368  1.9
 10000   12.1  53.8   245    8    4   9.6   5.2   27.3  81.1    -0.7    343  1.7
  9750   12.7  54.9   240    8    4   9.8   5.4   27.2  81.0    -0.7    316  1.6
  9500   13.4  56.1   235    8    4   6.7   3.7   27.2  81.0    -0.8    290  1.5
  9250   13.6  56.5   235    8    4   2.7   1.5   26.7  80.1    -1.3    275  1.4
  9000   13.8  56.8   230    9    4   3.6   2.0   26.2  79.2    -1.8    261  1.3
  8750   14.1  57.4   230    9    5   4.1   2.2   25.8  78.4    -2.3    246  1.3
  8500   14.3  57.7   225    9    5   2.9   1.6   25.3  77.6    -2.8    232  1.2
  8250   14.4  57.9   225    8    4   1.8   1.0   24.7  76.5    -3.5    222  1.1
  8000   14.5  58.1   220    8    4   2.1   1.2   24.1  75.4    -4.1    213  1.1
  7750   14.5  58.1   210    8    4   2.0   1.1   23.5  74.4    -4.8    203  1.0
  7500   14.6  58.3   200    8    4   1.7   0.9   22.9  73.3    -5.5    193  1.0
  7250   14.6  58.3   185    8    4   1.6   0.9   22.3  72.2    -6.2    185  0.9
  7000   14.6  58.3   175    9    5   1.5   0.8   21.7  71.0    -6.9    177  0.9
  6750   14.7  58.5   165   10    5   3.6   2.0   21.1  70.0    -7.6    168  0.9
  6500   15.0  59.0   155   10    5   5.8   3.2   20.8  69.4    -8.0    151  0.8
  6250   15.4  59.7   150   10    5   5.7   3.1   20.5  68.8    -8.4    132  0.7
  6000   15.8  60.4   145    9    5   6.0   3.3   20.2  68.3    -8.7    113  0.6
  5750   16.2  61.2   135    8    4   5.1   2.8   19.9  67.8    -9.1     94  0.5
  5500   16.4  61.5   125    6    3   2.7   1.5   19.5  67.1    -9.6     80  0.4

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

           08/26/2014 at 0900 MDT          |       08/26/2014 at 1200 MDT
                                           |
K index... +29.6  LI... -5.4               | K index... +26.4  LI... -6.7
CAPE... +1363.6  CIN... -72.6              | CAPE... +1777.3  CIN... -47.0
                                           |
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 -64.0 -83.2  245  39 20   0.9   0.5 | -63.1 -81.6  240  31 16   1.0   0.5
 45000 -61.5 -78.7  240  55 28   3.7   2.1 | -60.8 -77.4  235  56 29   2.6   1.4
 40000 -54.9 -66.8  245  59 30   7.7   4.2 | -55.9 -68.6  240  67 34   9.0   4.9
 38000 -50.2 -58.4  240  55 28   7.8   4.3 | -50.4 -58.7  235  62 32   9.1   5.0
 36000 -45.5 -49.9  240  52 27   7.8   4.3 | -44.9 -48.8  230  58 30   9.3   5.1
 34000 -40.8 -41.4  235  48 25   7.9   4.3 | -40.1 -40.2  230  55 28   7.7   4.2
 32000 -36.1 -33.0  235  45 23   7.8   4.3 | -35.5 -31.9  230  52 27   7.6   4.2
 30000 -31.6 -24.9  235  41 21   7.4   4.1 | -30.4 -22.7  235  45 23   7.4   4.1
 29000 -28.9 -20.0  230  39 20   7.4   4.1 | -28.2 -18.8  235  41 21   7.4   4.1
 28000 -26.7 -16.1  230  37 19   7.4   4.1 | -26.0 -14.8  235  38 19   7.4   4.0
 27000 -24.5 -12.1  230  36 18   7.5   4.1 | -23.8 -10.8  235  36 19   7.4   4.0
 26000 -22.3  -8.1  230  34 18   7.5   4.1 | -21.7  -7.1  235  35 18   7.4   4.1
 25000 -20.1  -4.2  230  33 17   7.3   4.0 | -19.5  -3.1  235  33 17   7.2   3.9
 24000 -18.1  -0.6  230  31 16   6.5   3.6 | -17.6   0.3  235  30 16   6.2   3.4
 23000 -16.3   2.7  230  29 15   6.5   3.6 | -15.8   3.6  240  27 14   6.3   3.4
 22000 -14.4   6.1  230  26 14   6.5   3.6 | -14.0   6.8  240  25 13   6.2   3.4
 21000 -12.5   9.5  230  25 13   6.6   3.6 | -12.2  10.0  245  22 11   5.9   3.2
 20000 -10.5  13.1  230  23 12   6.6   3.6 | -10.5  13.1  250  19 10   5.9   3.2
 19500  -9.6  14.7  225  22 11   6.7   3.7 |  -9.6  14.7  255  18  9   5.8   3.2
 19000  -8.7  16.3  230  21 11   5.3   2.9 |  -8.7  16.3  260  17  9   7.0   3.9
 18500  -7.9  17.8  230  18  9   5.6   3.1 |  -7.7  18.1  260  16  8   7.0   3.8
 18000  -7.0  19.4  235  16  8   6.9   3.8 |  -6.7  19.9  260  15  8   7.0   3.8
 17500  -5.8  21.6  235  13  7   8.4   4.6 |  -5.7  21.7  255  13  7   7.1   3.9
 17000  -4.5  23.9  240  10  5   8.6   4.7 |  -4.7  23.5  255  11  6   7.1   3.9
 16500  -3.4  25.9  250   7  4   7.0   3.8 |  -3.6  25.5  250   9  5   6.8   3.7
 16000  -2.4  27.7  265   6  3   7.2   3.9 |  -2.6  27.3  240   7  4   6.8   3.8
 15500  -1.4  29.5  290   5  3   7.8   4.3 |  -1.0  30.2  230   5  3   8.0   4.4
 15000  -0.3  31.5  295   5  3   7.9   4.4 |   0.1  32.2  230   4  2   7.8   4.3
 14500   1.5  34.7  305   5  3   8.3   4.6 |   1.4  34.5  235   2  1   9.0   4.9
 14000   2.8  37.0  310   5  3   8.3   4.5 |   2.7  36.9  250   1  1   9.0   4.9
 13500   4.0  39.2  315   5  2   8.9   4.9 |   4.0  39.2  295   1  0   8.9   4.9
 13000   5.4  41.7  320   5  2   9.1   5.0 |   5.3  41.5  320   2  1   8.9   4.9
 12500   6.7  44.1  320   5  2   9.2   5.0 |   6.7  44.1  330   2  1   9.0   5.0
 12000   8.1  46.6  330   5  2   9.2   5.1 |   8.0  46.4  340   3  1   9.1   5.0
 11500   9.4  48.9  335   5  2   8.8   4.8 |   9.4  48.9  345   3  2   9.0   4.9
 11000  10.6  51.1  325   4  2   8.0   4.4 |  10.7  51.3  345   4  2   8.5   4.7
 10500  11.8  53.2  310   4  2   3.8   2.1 |  12.0  53.6  345   4  2   4.3   2.3
 10250  11.8  53.2  310   4  2   3.5   1.9 |  12.2  54.0  345   4  2   5.0   2.7
 10000  12.4  54.3  300   4  2   9.9   5.4 |  12.9  55.2  345   4  2  11.4   6.3
  9750  13.0  55.4  290   4  2   9.7   5.3 |  13.6  56.5  345   4  2  10.6   5.8
  9500  13.7  56.7  280   4  2   6.9   3.8 |  14.3  57.7  340   4  2   7.5   4.1
  9250  14.0  57.2  275   4  2   3.9   2.1 |  14.7  58.5  340   4  2   4.2   2.3
  9000  14.3  57.7  275   4  2   5.2   2.9 |  15.0  59.0  335   4  2   6.3   3.4
  8750  14.6  58.3  275   5  2   5.4   2.9 |  15.5  59.9  330   4  2   6.7   3.7
  8500  14.9  58.8  275   5  2   2.1   1.2 |  15.8  60.4  330   3  2   3.5   1.9
  8250  14.8  58.6  265   5  2   0.1   0.1 |  15.9  60.6  330   3  1   1.8   1.0
  8000  14.8  58.6  260   5  2  -0.3  -0.1 |  15.9  60.6  325   2  1   1.0   0.5
  7750  14.7  58.5  255   5  2  -1.1  -0.6 |  15.8  60.4  330   2  1   1.1   0.6
  7500  14.6  58.3  240   5  2   0.6   0.4 |  15.9  60.6  350   1  1   5.3   2.9
  7250  14.6  58.3  220   4  2   1.5   0.8 |  16.2  61.2  030   2  1   6.7   3.7
  7000  14.6  58.3  200   5  3   1.0   0.5 |  16.6  61.9  050   3  1   7.2   4.0
  6750  14.6  58.3  180   6  3   4.9   2.7 |  17.0  62.6  055   3  2   9.7   5.3
  6500  15.1  59.2  170   6  3   8.6   4.7 |  17.8  64.0  055   3  2  10.6   5.8
  6250  15.7  60.3  155   5  3   7.3   4.0 |  18.6  65.5  055   4  2   9.9   5.4
  6000  16.2  61.2  140   5  2   9.7   5.3 |  19.3  66.7  055   4  2  11.7   6.4
  5750  17.1  62.8  130   5  2  14.1   7.8 |  20.4  68.7  055   4  2  17.6   9.7
  5500  18.1  64.6  125   4  2  14.8   8.1 |  21.9  71.4  055   4  2  22.2  12.2

           08/26/2014 at 1500 MDT          |       08/26/2014 at 1800 MDT
                                           |
K index... +24.1  LI... -7.0               | K index... +31.7  LI... -6.2
CAPE... +2090.2  CIN... -10.3              | CAPE... +1723.2  CIN... -0.9
                                           |
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  230  31 16   0.6   0.3 | -62.5 -80.5  230  32 16   1.5   0.8
 45000 -61.0 -77.8  235  57 29   3.6   2.0 | -59.9 -75.8  235  53 27   2.2   1.2
 40000 -55.0 -67.0  250  67 35   7.8   4.3 | -55.4 -67.7  235  67 34   9.1   5.0
 38000 -50.2 -58.4  245  61 31   7.9   4.3 | -49.9 -57.8  225  56 29   9.2   5.1
 36000 -45.5 -49.9  240  55 28   7.7   4.2 | -44.3 -47.7  215  46 24   9.3   5.1
 34000 -40.2 -40.4  230  53 27   9.0   4.9 | -39.1 -38.4  210  38 20   8.6   4.7
 32000 -34.2 -29.6  225  53 28   9.6   5.3 | -33.3 -27.9  205  30 15   9.3   5.1
 30000 -29.2 -20.6  230  46 24   8.2   4.5 | -28.7 -19.7  210  25 13   7.7   4.2
 29000 -26.8 -16.2  230  42 21   8.2   4.5 | -26.4 -15.5  215  23 12   7.8   4.3
 28000 -24.5 -12.1  235  38 19   6.4   3.5 | -24.1 -11.4  215  21 11   6.9   3.8
 27000 -22.6  -8.7  235  35 18   6.2   3.4 | -22.1  -7.8  215  19 10   6.8   3.7
 26000 -20.8  -5.4  235  32 16   6.2   3.4 | -20.1  -4.2  210  18  9   6.8   3.7
 25000 -18.9  -2.0  235  29 15   6.3   3.4 | -18.1  -0.6  210  16  8   6.7   3.7
 24000 -17.0   1.4  235  26 13   6.7   3.7 | -16.3   2.7  210  14  7   6.0   3.3
 23000 -15.0   5.0  240  23 12   6.7   3.7 | -14.5   5.9  205  11  6   6.0   3.3
 22000 -13.0   8.6  240  20 10   6.4   3.5 | -12.8   9.0  205   8  4   5.9   3.2
 21000 -11.4  11.5  245  16  8   5.5   3.0 | -11.2  11.8  190   6  3   5.3   2.9
 20000  -9.8  14.4  245  12  6   5.5   3.0 |  -9.6  14.7  170   5  3   5.3   2.9
 19500  -9.0  15.8  250  11  6   5.4   3.0 |  -8.8  16.2  155   5  3   5.2   2.9
 19000  -8.1  17.4  250   9  5   6.6   3.6 |  -8.0  17.6  145   5  3   6.6   3.6
 18500  -7.2  19.0  255   8  4   6.5   3.6 |  -7.0  19.4  140   5  3   6.6   3.6
 18000  -6.2  20.8  255   7  4   6.6   3.6 |  -6.1  21.0  130   6  3   6.5   3.6
 17500  -5.2  22.6  260   6  3   6.8   3.7 |  -5.1  22.8  125   6  3   6.4   3.5
 17000  -4.2  24.4  260   5  3   6.8   3.7 |  -4.2  24.4  120   5  3   6.4   3.5
 16500  -3.2  26.2  255   4  2   7.0   3.9 |  -3.3  26.1  115   5  3   6.7   3.7
 16000  -1.7  28.9  225   3  2   7.1   3.9 |  -1.8  28.8  115   5  3   6.7   3.7
 15500  -0.7  30.7  195   3  2   7.5   4.1 |  -0.8  30.6  115   6  3   7.4   4.1
 15000   0.4  32.7  170   3  2   7.4   4.1 |   0.3  32.5  110   6  3   7.4   4.0
 14500   1.6  34.9  150   4  2   8.6   4.7 |   1.3  34.3  110   6  3   7.3   4.0
 14000   2.8  37.0  135   4  2   8.6   4.7 |   2.4  36.3  110   6  3   7.3   4.0
 13500   4.1  39.4  125   5  3   8.6   4.7 |   3.5  38.3  105   6  3   7.2   4.0
 13000   5.4  41.7  115   5  2   8.6   4.7 |   4.5  40.1  105   6  3   7.2   3.9
 12500   6.7  44.1  110   5  2   8.9   4.9 |   5.5  41.9  105   5  3   7.2   3.9
 12000   8.0  46.4  100   5  2   9.1   5.0 |   6.5  43.7  105   4  2   7.2   4.0
 11500   9.4  48.9  090   5  2   8.8   4.9 |   7.5  45.5  110   4  2   7.8   4.3
 11000  10.7  51.3  080   4  2   8.2   4.5 |   8.6  47.5  115   3  2   8.4   4.6
 10500  12.0  53.6  070   4  2   3.6   2.0 |   9.7  49.5  120   3  2   3.6   2.0
 10250  12.1  53.8  070   5  2   4.6   2.5 |   9.8  49.6  115   3  2   5.9   3.2
 10000  12.8  55.0  065   4  2  11.4   6.2 |  10.7  51.3  115   3  1  14.0   7.7
  9750  13.5  56.3  065   4  2  10.3   5.6 |  11.5  52.7  115   3  1  12.6   6.9
  9500  14.2  57.6  060   4  2   8.0   4.4 |  12.3  54.1  110   3  1  10.5   5.8
  9250  14.6  58.3  065   4  2   4.9   2.7 |  12.9  55.2  105   3  1   8.0   4.4
  9000  15.0  59.0  065   4  2   6.1   3.4 |  13.6  56.5  105   3  1  10.6   5.8
  8750  15.3  59.5  070   3  2   6.4   3.5 |  14.5  58.1  100   3  1  11.7   6.4
  8500  15.6  60.1  070   3  2   7.0   3.9 |  15.3  59.5  100   3  1  10.4   5.7
  8250  15.9  60.6  075   3  2   7.2   4.0 |  16.0  60.8  100   3  1   9.4   5.2
  8000  16.2  61.2  080   4  2   9.0   4.9 |  16.7  62.1  095   3  1  10.1   5.5
  7750  16.9  62.4  080   4  2  10.7   5.9 |  17.5  63.5  090   3  1  10.4   5.7
  7500  17.5  63.5  080   4  2  10.0   5.5 |  18.3  64.9  090   3  1  10.0   5.5
  7250  18.3  64.9  080   4  2   9.8   5.4 |  19.0  66.2  085   3  1   9.8   5.4
  7000  19.0  66.2  080   5  2   9.8   5.4 |  19.7  67.5  085   3  1   9.8   5.4
  6750  19.7  67.5  080   5  2  10.3   5.7 |  20.5  68.9  085   3  1  10.1   5.5
  6500  20.5  68.9  075   4  2  10.8   5.9 |  21.2  70.2  080   3  1  10.4   5.7
  6250  21.3  70.3  075   4  2  11.2   6.1 |  22.0  71.6  080   3  1  10.7   5.9
  6000  22.1  71.8  075   4  2  10.0   5.5 |  22.8  73.0  075   3  1   9.5   5.2
  5750  22.9  73.2  075   5  2  14.3   7.8 |  23.5  74.3  075   3  1  10.6   5.8
  5500  24.4  75.9  075   5  2  24.6  13.5 |  24.4  75.9  070   3  1  16.0   8.8
________________________________________________________________________________

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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