Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 190157
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1957 MDT Friday, April 18, 2014

This forecast is for Saturday, April 19, 2014:

If the trigger temperature of 66.9 F/19.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8508 ft MSL (3221 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... None
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................. 6283 ft MSL (996 ft AGL)
Thermal soaring outlook for Sunday 04/20....... 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....................... 23459 ft MSL (18172 ft AGL)
Wave soaring outlook for Sunday 04/20.......... Fair

Remarks...

Sunrise/Sunset.................... 06:16:06 / 19:40:47 MDT
Total possible sunshine........... 13 hr 24 min 41 sec (804 min 41 sec)
Altitude of sun at 12:58:36 MDT... 61.58 degrees

Upper air data from numerical model forecast valid on 04/19/2014 at 0600 MDT

Freezing level.................. 12335 ft MSL (7048 ft AGL)
Convective condensation level... 14810 ft MSL (9523 ft AGL)
Lifted condensation level....... 13294 ft MSL (8007 ft AGL)
Lifted index.................... +1.8
K index......................... +21.8

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  -61.1 -78.0   255   30   15   1.2   0.7      M     M       M      M    M
 45000  -59.4 -74.9   255   35   18  -1.9  -1.1      M     M       M      M    M
 40000  -63.8 -82.8   220   41   21  -2.5  -1.4      M     M       M      M    M
 38000  -60.8 -77.4   220   40   21   8.2   4.5      M     M       M      M    M
 36000  -55.9 -68.6   220   37   19   8.2   4.5      M     M       M      M    M
 34000  -50.9 -59.6   225   33   17   8.7   4.8      M     M       M      M    M
 32000  -45.7 -50.3   225   27   14   8.7   4.8      M     M       M      M    M
 30000  -40.7 -41.3   225   22   12   7.9   4.3   35.3  95.5    12.8      M    M
 29000  -38.4 -37.1   225   22   11   7.9   4.3   34.5  94.1    12.3      M    M
 28000  -35.4 -31.7   230   21   11   7.9   4.3   33.7  92.7    11.9      M    M
 27000  -33.2 -27.8   230   21   11   7.1   3.9   32.9  91.2    11.3      M    M
 26000  -31.1 -24.0   235   24   12   7.1   3.9   31.8  89.2    10.6      M    M
 25000  -28.9 -20.0   240   27   14   7.1   3.9   30.8  87.5    10.0      M    M
 24000  -26.8 -16.2   240   29   15   8.2   4.5   30.0  86.1     9.4      M    M
 23000  -24.4 -11.9   230   29   15   8.1   4.4   29.3  84.8     8.9      M    M
 22000  -22.0  -7.6   225   30   15   8.1   4.4   28.8  83.8     8.5      M    M
 21000  -19.7  -3.5   220   30   15   6.8   3.7   28.0  82.5     8.0      M    M
 20000  -17.7   0.1   210   29   15   6.9   3.8   27.0  80.5     7.1      M    M
 19500  -16.7   1.9   210   29   15   6.9   3.8   26.5  79.7     6.7      M    M
 19000  -15.7   3.7   205   29   15   6.8   3.7   26.0  78.8     6.4      M    M
 18500  -14.6   5.7   205   29   15   8.1   4.4   25.6  78.2     6.0      M    M
 18000  -13.4   7.9   205   28   14   8.0   4.4   25.3  77.6     5.8      M    M
 17500  -12.3   9.9   205   27   14   7.2   4.0   25.0  77.1     5.5      M    M
 17000  -11.3  11.7   210   25   13   6.8   3.7   24.5  76.1     5.0      M    M
 16500  -10.3  13.5   210   24   12   6.8   3.7   24.0  75.2     4.6      M    M
 16000   -9.3  15.3   215   22   11   7.5   4.1   23.6  74.4     4.2      M    M
 15500   -8.2  17.2   215   21   11   7.3   4.0   23.2  73.7     3.9      M    M
 15000   -7.0  19.4   215   19   10   8.9   4.9   22.9  73.2     3.6      M    M
 14500   -5.7  21.7   210   17    9   9.0   4.9   22.8  73.0     3.5      M    M
 14000   -3.8  25.2   205   14    7   8.0   4.4   22.5  72.4     3.2      M    M
 13500   -2.6  27.3   200   12    6   8.1   4.4   22.2  71.9     3.0      M    M
 13000   -1.4  29.5   200   10    5   8.1   4.4   21.9  71.5     2.7      M    M
 12500   -0.2  31.6   200    7    4   8.1   4.4   21.7  71.0     2.5      M    M
 12000    1.0  33.8   200    4    2   8.2   4.5   21.4  70.5     2.3      M    M
 11500    2.3  36.1   235    2    1   8.1   4.4   21.1  70.1     2.1      M    M
 11000    3.5  38.3   305    2    1   9.1   5.0   20.9  69.7     1.9      M    M
 10500    4.9  40.8   315    5    2  10.0   5.5   20.8  69.5     1.8      M    M
 10250    5.6  42.1   315    6    3   5.4   3.0   20.8  69.4     1.8      M    M
 10000    5.8  42.4   320    6    3   5.1   2.8   20.3  68.5     1.3      M    M
  9750    6.4  43.5   330    7    4   9.3   5.1   20.2  68.3     1.2      M    M
  9500    7.1  44.8   330    8    4   8.8   4.8   20.1  68.1     1.1      M    M
  9250    7.7  45.9   335    9    5   6.5   3.6   20.0  68.0     1.0      M    M
  9000    8.0  46.4   345    9    5   4.6   2.5   19.6  67.2     0.6      M    M
  8750    8.4  47.1   355    9    5   5.9   3.3   19.3  66.7     0.3      M    M
  8500    8.8  47.8   005   10    5   5.6   3.1   18.9  66.1    -0.0    215  1.1
  8250    9.3  48.7   015   10    5   6.0   3.3   18.6  65.5    -0.4    195  1.0
  8000    9.7  49.5   025   11    6   6.0   3.3   18.4  65.0    -0.7    175  0.9
  7750   10.1  50.2   030   12    6   5.5   3.0   18.1  64.5    -1.0    155  0.8
  7500   10.5  50.9   035   13    7   5.9   3.3   17.7  63.9    -1.3    136  0.7
  7250   11.0  51.8   040   14    7   7.1   3.9   17.5  63.5    -1.6    114  0.6
  7000   11.5  52.7   040   15    8   7.1   3.9   17.3  63.1    -1.8     91  0.5
  6750   12.0  53.6   040   15    8   7.1   3.9   17.1  62.8    -2.0     69  0.4
  6500   12.4  54.3   040   15    8   3.3   1.8   16.8  62.2    -2.3     49  0.2
  6250   12.4  54.3   040   12    6   0.1   0.1   16.1  61.0    -3.0     41  0.2
  6000   12.5  54.5   035    9    5   1.5   0.8   15.5  59.8    -3.8     33  0.2
  5750   12.5  54.5   025    6    3  -1.0  -0.6   14.8  58.6    -4.5     25  0.1
  5500   12.1  53.8   335    2    1  -6.8  -3.7   13.8  56.8    -5.6     29  0.1

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

           04/19/2014 at 0900 MDT          |       04/19/2014 at 1200 MDT
                                           |
K index... +23.1  LI... +1.6               | K index... +23.2  LI... +0.3
CAPE... 0.0  CIN... -0.2                   | CAPE... +20.0  CIN... -18.5
                                           |
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 -61.3 -78.3  245  25 13   1.0   0.5 | -60.9 -77.6  250  28 14   1.2   0.7
 45000 -59.9 -75.8  240  28 14  -1.1  -0.6 | -59.1 -74.4  235  30 16  -1.0  -0.5
 40000 -62.7 -80.9  220  39 20  -1.6  -0.9 | -62.1 -79.8  225  37 19  -1.8  -1.0
 38000 -60.1 -76.2  215  38 20   7.0   3.8 | -59.9 -75.8  220  35 18   6.1   3.4
 36000 -55.9 -68.6  215  35 18   7.0   3.8 | -56.2 -69.2  210  31 16   6.1   3.4
 34000 -51.4 -60.5  210  31 16   8.7   4.8 | -52.0 -61.6  200  27 14   8.9   4.9
 32000 -46.2 -51.2  215  26 13   8.7   4.8 | -46.7 -52.1  200  23 12   8.8   4.9
 30000 -41.1 -42.0  220  21 11   8.0   4.4 | -41.5 -42.7  205  18  9   8.1   4.4
 29000 -38.7 -37.7  225  19 10   8.0   4.4 | -38.5 -37.3  210  14  7   8.1   4.4
 28000 -35.7 -32.3  235  17  9   8.0   4.4 | -36.1 -33.0  215  11  5   8.1   4.4
 27000 -33.4 -28.1  240  16  8   7.5   4.1 | -33.7 -28.7  225   9  5   8.3   4.6
 26000 -31.2 -24.2  245  16  8   7.5   4.1 | -31.2 -24.2  230  10  5   8.3   4.6
 25000 -29.0 -20.2  250  16  8   7.5   4.1 | -28.7 -19.7  230  11  6   8.3   4.6
 24000 -26.7 -16.1  250  17  9   8.4   4.6 | -26.3 -15.3  230  13  7   7.8   4.3
 23000 -24.2 -11.6  235  18  9   8.3   4.6 | -24.0 -11.2  230  15  8   7.9   4.3
 22000 -21.8  -7.2  225  21 11   8.3   4.6 | -21.6  -6.9  225  18  9   7.9   4.3
 21000 -19.5  -3.1  215  23 12   6.6   3.6 | -19.5  -3.1  220  20 10   6.4   3.5
 20000 -17.5   0.5  205  25 13   6.6   3.6 | -17.6   0.3  205  22 11   6.5   3.6
 19500 -16.6   2.1  205  26 13   6.6   3.6 | -16.6   2.1  200  23 12   6.5   3.6
 19000 -15.6   3.9  200  27 14   6.6   3.6 | -15.7   3.7  195  24 13   6.5   3.6
 18500 -14.5   5.9  195  28 14   7.7   4.2 | -14.7   5.5  195  24 13   7.2   3.9
 18000 -13.4   7.9  195  27 14   7.6   4.2 | -13.6   7.5  190  23 12   7.1   3.9
 17500 -12.3   9.9  195  26 14   6.7   3.7 | -12.6   9.3  190  22 12   7.1   3.9
 17000 -11.5  11.3  190  25 13   6.1   3.3 | -11.6  11.1  185  21 11   7.1   3.9
 16500 -10.6  12.9  190  23 12   6.1   3.4 | -10.5  13.1  180  19 10   7.1   3.9
 16000  -9.6  14.7  185  20 11   7.0   3.8 |  -9.5  14.9  175  17  9   6.6   3.6
 15500  -8.6  16.5  185  18  9   6.8   3.8 |  -8.6  16.5  170  16  8   6.8   3.7
 15000  -7.6  18.3  185  15  8   8.3   4.6 |  -7.7  18.1  160  14  7   4.9   2.7
 14500  -6.3  20.7  190  14  7   8.3   4.6 |  -6.7  19.9  155  12  6   4.8   2.7
 14000  -4.4  24.1  190  12  6   8.6   4.7 |  -6.0  21.2  145   9  5   4.0   2.2
 13500  -3.2  26.2  190  10  5   8.7   4.8 |  -5.4  22.3  130   7  4   3.8   2.1
 13000  -2.0  28.4  185   7  4   7.0   3.8 |  -4.6  23.7  115   5  3   7.5   4.1
 12500  -0.9  30.4  160   3  1   7.2   4.0 |  -3.5  25.7  085   3  2   6.8   3.7
 12000   0.1  32.2  055   2  1   6.2   3.4 |  -2.2  28.0  040   2  1  10.6   5.8
 11500   1.0  33.8  010   5  2   6.1   3.3 |  -0.7  30.7  360   2  1  10.7   5.9
 11000   2.1  35.8  360   7  4   8.0   4.4 |   0.7  33.3  330   3  1   7.1   3.9
 10500   3.2  37.8  360   7  4   8.9   4.9 |   1.7  35.1  305   3  2   8.0   4.4
 10250   3.8  38.8  355   8  4   4.4   2.4 |   2.3  36.1  295   4  2   4.2   2.3
 10000   4.0  39.2  355   7  4   4.1   2.3 |   2.5  36.5  300   4  2   5.7   3.1
  9750   4.5  40.1  360   7  3   8.3   4.6 |   3.2  37.8  310   4  2  10.3   5.6
  9500   5.1  41.2  360   6  3   7.5   4.1 |   3.9  39.0  315   4  2   9.1   5.0
  9250   5.6  42.1  360   5  3   6.3   3.5 |   4.5  40.1  325   5  2   6.5   3.6
  9000   6.0  42.8  355   5  3   6.6   3.6 |   4.8  40.6  345   4  2   6.3   3.4
  8750   6.6  43.9  350   5  3   8.5   4.7 |   5.4  41.7  010   4  2   8.5   4.7
  8500   7.2  45.0  345   5  3   7.9   4.3 |   5.9  42.6  035   4  2   8.4   4.6
  8250   7.8  46.0  350   6  3   7.3   4.0 |   6.5  43.7  045   5  3   9.3   5.1
  8000   8.3  46.9  005   7  3   6.5   3.5 |   7.2  45.0  045   5  3   9.6   5.3
  7750   8.7  47.7  015   8  4   6.0   3.3 |   7.9  46.2  045   5  3   9.7   5.3
  7500   9.1  48.4  020  10  5   5.7   3.1 |   8.7  47.7  045   5  3   9.9   5.4
  7250   9.5  49.1  030  10  5   5.5   3.0 |   9.4  48.9  045   5  3  10.1   5.5
  7000   9.9  49.8  035   9  5   5.6   3.1 |  10.2  50.4  045   5  3  10.1   5.6
  6750  10.3  50.5  040   8  4   6.2   3.4 |  10.9  51.6  045   5  3  10.5   5.8
  6500  10.8  51.4  040   6  3   9.0   5.0 |  11.7  53.1  045   5  3  10.3   5.6
  6250  11.6  52.9  045   5  3  10.9   6.0 |  12.5  54.5  045   5  3  10.2   5.6
  6000  12.4  54.3  045   4  2   9.8   5.4 |  13.2  55.8  045   5  3   9.5   5.2
  5750  13.1  55.6  045   4  2  11.5   6.3 |  14.0  57.2  045   5  3  12.4   6.8
  5500  14.1  57.4  045   4  2  16.2   8.9 |  15.1  59.2  045   5  3  19.4  10.7

           04/19/2014 at 1500 MDT          |       04/19/2014 at 1800 MDT
                                           |
K index... +25.0  LI... +0.5               | K index... +25.1  LI... +1.1
CAPE... +40.0  CIN... M                    | CAPE... +16.5  CIN... M
                                           |
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 -60.6 -77.1  245  26 13   1.6   0.9 | -60.5 -76.9  250  24 13   0.9   0.5
 45000 -58.4 -73.1  235  33 17  -1.4  -0.8 | -59.3 -74.7  250  28 15  -0.5  -0.2
 40000 -60.1 -76.2  230  34 17  -1.1  -0.6 | -59.8 -75.6  235  26 13  -0.3  -0.2
 38000 -58.6 -73.5  230  31 16   4.5   2.4 | -58.2 -72.8  230  26 13   4.1   2.3
 36000 -55.9 -68.6  225  28 14   4.5   2.4 | -55.7 -68.3  225  25 13   4.1   2.3
 34000 -52.4 -62.3  225  25 13   8.7   4.8 | -52.4 -62.3  220  25 13   8.4   4.6
 32000 -47.2 -53.0  220  21 11   8.7   4.8 | -47.3 -53.1  220  23 12   8.4   4.6
 30000 -41.4 -42.5  220  16  8   8.5   4.7 | -41.6 -42.9  220  21 11   8.6   4.7
 29000 -38.8 -37.8  220  13  7   8.5   4.7 | -39.0 -38.2  215  19 10   8.7   4.7
 28000 -36.3 -33.3  215  10  5   8.5   4.7 | -36.4 -33.5  215  18  9   8.7   4.7
 27000 -33.8 -28.8  215   9  5   8.3   4.6 | -33.9 -29.0  215  17  9   8.3   4.6
 26000 -31.3 -24.3  220  10  5   8.3   4.6 | -31.4 -24.5  215  16  8   8.3   4.6
 25000 -28.8 -19.8  225  12  6   8.3   4.6 | -28.9 -20.0  220  14  7   8.3   4.6
 24000 -26.4 -15.5  230  13  7   7.9   4.3 | -26.4 -15.5  225  14  7   8.3   4.5
 23000 -24.0 -11.2  225  15  8   8.0   4.4 | -24.0 -11.2  235  14  7   8.3   4.6
 22000 -21.6  -6.9  225  17  9   8.0   4.4 | -21.5  -6.7  240  15  8   8.3   4.6
 21000 -19.4  -2.9  220  18  9   6.7   3.7 | -19.2  -2.6  245  15  8   7.1   3.9
 20000 -17.4   0.7  210  17  9   6.8   3.7 | -17.1   1.2  245  16  8   7.1   3.9
 19500 -16.4   2.5  205  17  9   6.8   3.7 | -16.0   3.2  245  16  8   7.2   3.9
 19000 -15.4   4.3  205  17  9   6.9   3.8 | -15.0   5.0  250  16  8   7.3   4.0
 18500 -14.5   5.9  200  17  9   6.1   3.3 | -14.0   6.8  250  16  8   6.2   3.4
 18000 -13.6   7.5  205  16  8   6.2   3.4 | -13.1   8.4  250  16  8   6.3   3.4
 17500 -12.7   9.1  205  16  8   6.4   3.5 | -12.2  10.0  250  16  8   5.6   3.1
 17000 -11.7  10.9  205  15  8   6.7   3.7 | -11.5  11.3  250  15  7   5.1   2.8
 16500 -10.7  12.7  200  14  7   6.7   3.7 | -10.8  12.6  245  14  7   5.0   2.8
 16000  -9.8  14.4  200  13  7   6.1   3.4 | -10.0  14.0  245  12  6   5.6   3.1
 15500  -8.9  16.0  195  12  6   6.2   3.4 |  -9.2  15.4  240  11  6   5.5   3.0
 15000  -7.6  18.3  185  10  5   6.0   3.3 |  -7.9  17.8  235   9  4   6.4   3.5
 14500  -6.7  19.9  170   8  4   6.0   3.3 |  -7.0  19.4  230   7  3   6.4   3.5
 14000  -5.9  21.4  155   7  3   5.6   3.0 |  -6.0  21.2  220   5  3   6.5   3.6
 13500  -5.1  22.8  140   5  3   5.6   3.1 |  -5.1  22.8  210   4  2   6.6   3.6
 13000  -4.3  24.3  130   4  2   5.2   2.9 |  -4.2  24.4  200   3  2   6.2   3.4
 12500  -3.5  25.7  145   1  1   5.2   2.9 |  -3.3  26.1  200   3  1   6.2   3.4
 12000  -2.7  27.1  000   0  0   5.6   3.1 |  -2.4  27.7  200   3  1   5.9   3.3
 11500  -1.9  28.6  000   0  0   5.5   3.0 |  -1.5  29.3  195   2  1   6.0   3.3
 11000  -1.1  30.0  345   1  0   6.2   3.4 |  -0.7  30.7  200   2  1   5.9   3.2
 10500  -0.2  31.6  005   2  1   6.8   3.7 |   0.2  32.4  240   1  1   6.6   3.6
 10250   0.2  32.4  005   2  1   3.7   2.0 |   0.6  33.1  280   1  1   3.0   1.7
 10000   0.4  32.7  010   2  1   6.6   3.6 |   0.7  33.3  285   1  1   4.8   2.6
  9750   1.2  34.2  015   2  1  11.8   6.5 |   1.4  34.5  310   2  1   9.7   5.3
  9500   2.0  35.6  015   2  1  10.5   5.8 |   2.0  35.6  320   2  1   8.4   4.6
  9250   2.7  36.9  020   3  1   8.3   4.6 |   2.6  36.7  325   3  1   6.2   3.4
  9000   3.3  37.9  020   3  1   8.7   4.8 |   2.9  37.2  330   3  2   5.1   2.8
  8750   4.1  39.4  025   3  1  11.5   6.3 |   3.4  38.1  330   4  2   6.5   3.6
  8500   4.9  40.8  025   3  1  10.8   5.9 |   3.8  38.8  335   5  2   6.9   3.8
  8250   5.7  42.3  030   3  1  10.2   5.6 |   4.4  39.9  335   5  3   8.3   4.6
  8000   6.4  43.5  030   3  1   9.9   5.4 |   5.0  41.0  340   5  3   8.9   4.9
  7750   7.1  44.8  030   3  1   9.3   5.1 |   5.6  42.1  345   5  3   8.8   4.8
  7500   7.8  46.0  035   3  1   9.8   5.4 |   6.3  43.3  345   5  3   9.5   5.2
  7250   8.6  47.5  035   3  1  10.6   5.8 |   7.0  44.6  345   5  3  10.2   5.6
  7000   9.3  48.7  035   3  1  10.2   5.6 |   7.8  46.0  345   5  3  10.0   5.5
  6750  10.1  50.2  040   3  1   9.3   5.1 |   8.5  47.3  350   5  3  10.0   5.5
  6500  10.8  51.4  040   3  1   9.9   5.4 |   9.3  48.7  350   5  3  10.2   5.6
  6250  11.6  52.9  040   3  1  11.2   6.1 |  10.0  50.0  350   5  3  10.6   5.8
  6000  12.4  54.3  045   3  1   9.9   5.4 |  10.8  51.4  350   5  3   9.8   5.4
  5750  13.1  55.6  045   3  1  12.1   6.7 |  11.6  52.9  350   5  3  11.4   6.3
  5500  14.3  57.7  045   3  1  18.6  10.2 |  12.6  54.7  350   5  2  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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