Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271252
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0652 MDT Monday, July 27, 2015

This forecast is for Monday, July 27, 2015:

If the trigger temperature of 84.7 F/29.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1232 ft/min (6.3 m/s)
   Maximum height of thermals.................. 18879 ft MSL (13594 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1015 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................. 14844 ft MSL (9558 ft AGL)
Thermal soaring outlook for Tuesday 07/28...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 14374 ft MSL (9089 ft AGL)
Wave soaring outlook for Tuesday 07/28......... Poor

Remarks...

Sunrise/Sunset.................... 05:53:48 / 20:18:26 MDT
Total possible sunshine........... 14 hr 24 min 39 sec (864 min 39 sec)
Altitude of sun at 13:05:56 MDT... 69.36 degrees

Upper air data from rawinsonde observation taken on 07/27/2015 at 0600 MDT

Freezing level.................. 16791 ft MSL (11506 ft AGL)
Convective condensation level... 15004 ft MSL (9719 ft AGL)
Lifted condensation level....... 16393 ft MSL (11107 ft AGL)
Lifted index.................... -6.8
K index......................... +22.8

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  -71.1 -96.0   215   39   20   6.6   3.6   72.8 163.0    21.4      M    M
 45000  -61.8 -79.2   220   54   28   8.5   4.7   64.1 147.3    17.5      M    M
 40000  -50.2 -58.4   215   49   25   8.9   4.9   58.1 136.7    14.9      M    M
 38000  -44.8 -48.6   215   48   25   8.9   4.9   57.3 135.1    14.6      M    M
 36000  -39.5 -39.1   215   47   24   8.4   4.6   56.9 134.5    14.8      M    M
 34000  -36.4 -33.5   225   45   23   4.7   2.6   53.1 127.6    12.3      M    M
 32000  -31.7 -25.1   235   46   24   8.3   4.5   51.6 124.9    11.5      M    M
 30000  -28.0 -18.4   240   42   22   4.4   2.4   48.8 119.8     9.7      M    M
 29000  -25.7 -14.3   240   42   21   8.0   4.4   47.9 118.3     9.1      M    M
 28000  -22.7  -8.9   245   41   21   7.4   4.1   47.1 116.8     8.6      M    M
 27000  -21.1  -6.0   240   40   21   6.8   3.7   45.5 114.0     7.3      M    M
 26000  -19.3  -2.7   230   40   20   8.4   4.6   44.2 111.5     6.3      M    M
 25000  -16.7   1.9   225   39   20   9.5   5.2   43.9 110.9     6.1      M    M
 24000  -17.0   1.4   225   33   17   3.6   2.0   40.0 104.0     2.9      M    M
 23000  -14.4   6.1   230   28   14   9.9   5.4   39.7 103.4     2.6      M    M
 22000  -12.0  10.4   230   23   12   8.4   4.6   39.0 102.3     2.1      M    M
 21000   -9.6  14.7   235   18    9   5.8   3.2   38.4 101.2     1.6      M    M
 20000   -7.8  18.0   245   13    7   8.6   4.7   37.3  99.1     0.5      M    M
 19500   -6.6  20.1   250   12    6   8.3   4.6   37.0  98.6     0.3      M    M
 19000   -5.3  22.5   255   11    6   8.4   4.6   36.8  98.2     0.1      M    M
 18500   -4.1  24.6   255   10    5   8.4   4.6   36.5  97.7    -0.1   1197  6.1
 18000   -2.9  26.8   255    8    4   8.4   4.6   36.3  97.3    -0.3   1145  5.8
 17500   -1.6  29.1   250    9    5   7.6   4.2   36.0  96.9    -0.6   1093  5.6
 17000   -0.6  30.9   250   10    5   7.1   3.9   35.6  96.0    -1.0   1048  5.3
 16500    0.4  32.7   245   11    6   7.1   3.9   35.1  95.2    -1.5   1002  5.1
 16000    1.5  34.7   245   12    6   7.1   3.9   34.7  94.5    -1.9    957  4.9
 15500    2.5  36.5   250   12    6   7.1   3.9   34.2  93.6    -2.3    911  4.6
 15000    3.5  38.3   255   12    6   7.1   3.9   33.8  92.9    -2.8    866  4.4
 14500    4.5  40.1   255   13    7   7.1   3.9   33.4  92.0    -3.2    820  4.2
 14000    6.2  43.2   255   15    8   8.4   4.6   32.8  91.1    -3.8    748  3.8
 13500    7.4  45.3   260   13    7   8.3   4.6   32.6  90.7    -4.0    696  3.5
 13000    8.7  47.7   260   11    6   8.3   4.6   32.4  90.4    -4.2    645  3.3
 12500    9.9  49.8   260    9    5   8.3   4.6   32.2  89.9    -4.5    593  3.0
 12000   11.1  52.0   260    7    4   8.4   4.6   32.0  89.5    -4.7    542  2.8
 11500   12.3  54.1   280    9    5   8.4   4.6   31.7  89.1    -5.0    491  2.5
 11000   13.6  56.5   290   11    6   8.4   4.6   31.5  88.7    -5.3    439  2.2
 10500   14.8  58.6   290    9    4   8.3   4.6   31.3  88.3    -5.5    388  2.0
 10250   15.4  59.7   285    8    4   7.6   4.1   31.1  88.0    -5.7    363  1.8
 10000   15.9  60.6   275    9    4   7.2   4.0   30.9  87.6    -6.0    340  1.7
  9750   16.4  61.5   270    9    5   7.0   3.9   30.7  87.3    -6.2    317  1.6
  9500   16.9  62.4   260   10    5   8.1   4.4   30.5  87.0    -6.4    295  1.5
  9250   17.4  63.3   255   11    6   3.8   2.1   30.3  86.6    -6.6    272  1.4
  9000   17.4  63.3   250   12    6  -0.1  -0.1   29.6  85.3    -7.4    265  1.3
  8750   17.4  63.3   235   13    7   0.2   0.1   28.9  84.0    -8.1    257  1.3
  8500   17.4  63.3   225   14    7   4.6   2.5   28.3  82.9    -8.8    249  1.3
  8250   18.0  64.4   215   15    8   8.9   4.9   28.1  82.6    -9.1    225  1.1
  8000   18.5  65.3   210   17    9   7.7   4.2   28.0  82.4    -9.3    202  1.0
  7750   19.1  66.4   200   16    8   8.4   4.6   27.9  82.1    -9.5    178  0.9
  7500   19.6  67.3   195   15    8   7.2   3.9   27.7  81.9    -9.7    155  0.8
  7250   19.5  67.1   185   15    8 -10.4  -5.7   27.0  80.7   -10.5    150  0.8
  7000   18.0  64.4   175   15    8  -8.5  -4.7   25.2  77.3   -12.8    187  0.9
  6750   18.2  64.8   180   11    6   5.0   2.7   24.6  76.2   -13.4    175  0.9
  6500   18.3  64.9   195    8    4   0.4   0.2   24.0  75.2   -14.0    163  0.8
  6250   18.2  64.8   215    5    3  -4.5  -2.5   23.1  73.6   -14.9    159  0.8
  6000   17.8  64.0   260    5    3  -1.1  -0.6   22.0  71.7   -16.0    163  0.8
  5750   18.2  64.8   265    4    2   7.8   4.3   21.6  71.0   -16.4    145  0.7
  5500   18.6  65.5   265    3    2   0.1   0.1   21.3  70.4   -16.8    125  0.6

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

           07/27/2015 at 0900 MDT          |       07/27/2015 at 1200 MDT
                                           |
K index... +27.9  LI... -2.5               | K index... +27.4  LI... -2.9
CAPE... +333.2  CIN... -105.7              | CAPE... +438.2  CIN... -30.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.0 -86.8  225  30 15   1.1   0.6 | -65.0 -85.0  210  37 19   0.5   0.3
 45000 -61.3 -78.3  225  43 22   7.1   3.9 | -61.3 -78.3  215  48 25   6.3   3.5
 40000 -50.6 -59.1  215  43 22   7.4   4.1 | -51.5 -60.7  220  41 21   7.6   4.2
 38000 -46.1 -51.0  220  44 22   7.4   4.1 | -46.9 -52.4  220  43 22   7.6   4.2
 36000 -41.1 -42.0  220  44 23   7.6   4.2 | -41.8 -43.2  220  45 23   7.8   4.3
 34000 -36.4 -33.5  225  42 22   7.8   4.3 | -37.0 -34.6  225  43 22   7.9   4.4
 32000 -31.8 -25.2  230  40 20   8.2   4.5 | -32.2 -26.0  225  41 21   8.3   4.5
 30000 -27.3 -17.1  230  35 18   7.4   4.1 | -27.5 -17.5  225  37 19   7.8   4.3
 29000 -25.0 -13.0  235  33 17   7.4   4.1 | -25.1 -13.2  230  35 18   7.8   4.3
 28000 -22.8  -9.0  235  31 16   6.4   3.5 | -22.8  -9.0  230  33 17   6.8   3.7
 27000 -21.0  -5.8  230  30 16   6.2   3.4 | -20.9  -5.6  230  32 17   6.6   3.6
 26000 -19.1  -2.4  230  30 15   6.3   3.5 | -18.9  -2.0  225  31 16   6.7   3.7
 25000 -17.3   0.9  225  29 15   6.4   3.5 | -16.9   1.6  225  31 16   6.7   3.7
 24000 -15.4   4.3  225  28 14   6.7   3.7 | -15.2   4.6  225  29 15   5.8   3.2
 23000 -13.4   7.9  225  27 14   6.8   3.7 | -13.5   7.7  225  28 14   5.9   3.2
 22000 -11.5  11.3  225  26 14   6.8   3.7 | -11.8  10.8  230  27 14   6.1   3.4
 21000  -9.6  14.7  225  25 13   6.5   3.5 |  -9.9  14.2  230  26 13   6.7   3.7
 20000  -7.7  18.1  225  24 12   6.5   3.5 |  -7.9  17.8  235  26 13   6.7   3.7
 19500  -6.7  19.9  225  23 12   6.4   3.5 |  -6.9  19.6  235  25 13   6.7   3.7
 19000  -5.8  21.6  225  23 12   7.3   4.0 |  -5.9  21.4  235  25 13   7.9   4.3
 18500  -4.7  23.5  220  22 12   7.4   4.1 |  -4.7  23.5  235  25 13   8.0   4.4
 18000  -3.1  26.4  220  22 11   7.3   4.0 |  -3.0  26.6  235  25 13   7.7   4.2
 17500  -2.0  28.4  220  22 11   7.3   4.0 |  -1.9  28.6  230  25 13   7.6   4.2
 17000  -1.0  30.2  220  22 11   7.2   4.0 |  -0.8  30.6  230  25 13   7.7   4.2
 16500   0.1  32.2  220  22 11   7.0   3.8 |   0.4  32.7  230  24 12   7.9   4.4
 16000   1.1  34.0  220  21 11   7.0   3.8 |   1.6  34.9  230  23 12   7.9   4.3
 15500   2.1  35.8  220  20 10   7.3   4.0 |   2.7  36.9  230  22 12   8.1   4.4
 15000   3.2  37.8  225  19 10   7.3   4.0 |   3.9  39.0  230  21 11   8.1   4.4
 14500   4.2  39.6  225  18  9   7.7   4.2 |   5.1  41.2  235  20 10   8.4   4.6
 14000   5.4  41.7  230  16  8   7.9   4.3 |   6.4  43.5  235  18  9   8.5   4.7
 13500   6.5  43.7  235  15  8   8.3   4.6 |   7.6  45.7  240  17  9   8.4   4.6
 13000   7.8  46.0  240  14  7   9.2   5.0 |   8.8  47.8  245  15  8   8.1   4.5
 12500   9.2  48.6  245  14  7   9.2   5.1 |  10.0  50.0  250  13  7   8.1   4.5
 12000  10.5  50.9  255  14  7   9.3   5.1 |  11.1  52.0  255  12  6   8.2   4.5
 11500  11.9  53.4  260  15  8   9.2   5.1 |  12.3  54.1  260  11  6   8.2   4.5
 11000  13.2  55.8  260  15  8   8.5   4.7 |  13.3  55.9  260  10  5   6.8   3.7
 10500  14.4  57.9  265  15  8  11.5   6.3 |  14.3  57.7  255   8  4   9.6   5.3
 10250  15.4  59.7  265  15  8  11.8   6.5 |  15.1  59.2  250   7  4  11.2   6.1
 10000  16.1  61.0  265  15  8   8.2   4.5 |  15.7  60.3  245   6  3   8.8   4.8
  9750  16.8  62.2  270  15  8   9.2   5.0 |  16.4  61.5  235   6  3   9.5   5.2
  9500  17.4  63.3  270  15  8   8.9   4.9 |  17.1  62.8  230   5  3   9.1   5.0
  9250  18.1  64.6  270  15  8   9.1   5.0 |  17.7  63.9  225   5  3   9.0   4.9
  9000  18.8  65.8  270  14  7   9.2   5.0 |  18.4  65.1  220   5  3   9.7   5.3
  8750  19.4  66.9  270  14  7   9.2   5.1 |  19.2  66.6  220   5  3  10.2   5.6
  8500  20.1  68.2  275  14  7   9.1   5.0 |  19.9  67.8  220   5  2  10.1   5.6
  8250  20.8  69.4  275  13  7   8.8   4.8 |  20.7  69.3  220   5  2  11.5   6.3
  8000  21.4  70.5  275  12  6   7.8   4.3 |  21.5  70.7  220   5  2  10.5   5.8
  7750  21.9  71.4  275  12  6   7.3   4.0 |  22.2  72.0  220   5  2   8.8   4.8
  7500  22.4  72.3  275  11  6   6.8   3.7 |  22.9  73.2  220   4  2   9.5   5.2
  7250  22.9  73.2  275  11  6   5.7   3.1 |  23.6  74.5  220   4  2  10.1   5.5
  7000  23.2  73.8  275  10  5   4.6   2.5 |  24.4  75.9  220   4  2  10.2   5.6
  6750  23.5  74.3  270   9  5   3.0   1.6 |  25.1  77.2  220   4  2   9.3   5.1
  6500  23.6  74.5  270   9  4   1.4   0.8 |  25.8  78.4  220   4  2  10.1   5.6
  6250  23.6  74.5  260   7  4   0.9   0.5 |  26.7  80.1  220   4  2  11.5   6.3
  6000  23.5  74.3  250   6  3   0.7   0.4 |  27.5  81.5  220   4  2  11.2   6.1
  5750  23.4  74.1  235   5  2   2.4   1.3 |  28.4  83.1  220   4  2  11.4   6.2
  5500  23.7  74.7  215   4  2  11.5   6.3 |  29.4  84.9  220   3  2  18.2  10.0

           07/27/2015 at 1500 MDT          |       07/27/2015 at 1800 MDT
                                           |
K index... +32.0  LI... -2.9               | K index... +30.6  LI... -3.7
CAPE... +472.3  CIN... -2.6                | CAPE... +360.2  CIN... -16.2
                                           |
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 -65.4 -85.7  220  39 20   0.1   0.0 | -65.1 -85.2  235  37 19  -0.4  -0.2
 45000 -62.0 -79.6  225  51 26   6.5   3.6 | -62.1 -79.8  235  48 25   6.7   3.7
 40000 -51.8 -61.2  225  47 24   8.4   4.6 | -51.7 -61.1  230  51 26   8.4   4.6
 38000 -46.7 -52.1  225  47 24   8.4   4.6 | -46.7 -52.1  225  50 26   8.4   4.6
 36000 -41.1 -42.0  220  48 25   7.9   4.3 | -41.0 -41.8  220  50 26   8.0   4.4
 34000 -36.5 -33.7  225  47 24   7.6   4.2 | -36.4 -33.5  225  49 25   7.6   4.2
 32000 -31.9 -25.4  230  46 24   8.4   4.6 | -31.8 -25.2  230  48 25   7.8   4.3
 30000 -27.5 -17.5  230  44 23   7.4   4.1 | -27.5 -17.5  240  44 23   7.2   3.9
 29000 -25.3 -13.5  230  43 22   7.5   4.1 | -25.4 -13.7  240  43 22   7.2   3.9
 28000 -23.1  -9.6  230  43 22   7.0   3.9 | -23.2  -9.8  245  41 21   7.2   3.9
 27000 -21.0  -5.8  235  42 22   7.0   3.8 | -21.0  -5.8  250  41 21   7.2   3.9
 26000 -19.0  -2.2  235  42 22   7.0   3.9 | -18.9  -2.0  250  40 21   7.2   3.9
 25000 -16.9   1.6  235  42 22   7.0   3.8 | -16.7   1.9  250  40 20   7.1   3.9
 24000 -15.0   5.0  240  39 20   6.2   3.4 | -15.0   5.0  255  38 20   5.5   3.0
 23000 -13.2   8.2  240  36 18   6.2   3.4 | -13.4   7.9  255  37 19   5.6   3.1
 22000 -11.4  11.5  240  32 17   6.3   3.5 | -11.7  10.9  260  35 18   5.8   3.2
 21000  -9.5  14.9  240  29 15   6.6   3.6 | -10.2  13.6  255  32 17   5.6   3.1
 20000  -7.6  18.3  240  26 13   6.6   3.6 |  -8.6  16.5  255  30 15   5.8   3.2
 19500  -6.6  20.1  240  24 12   6.6   3.6 |  -7.8  18.0  250  28 14   5.6   3.1
 19000  -5.6  21.9  240  22 12   6.6   3.6 |  -6.8  19.8  250  27 14  10.2   5.6
 18500  -4.7  23.5  240  21 11   6.6   3.6 |  -4.5  23.9  250  25 13  10.8   5.9
 18000  -3.2  26.2  240  19 10   6.7   3.7 |  -3.1  26.4  250  24 13   8.9   4.9
 17500  -2.2  28.0  240  18  9   6.7   3.7 |  -1.8  28.8  250  23 12   8.6   4.7
 17000  -1.3  29.7  235  17  9   6.8   3.8 |  -0.6  30.9  250  21 11   8.4   4.6
 16500  -0.2  31.6  235  16  8   7.3   4.0 |   0.6  33.1  250  20 11   7.7   4.2
 16000   0.8  33.4  230  15  8   7.2   3.9 |   1.7  35.1  250  19 10   7.6   4.2
 15500   1.9  35.4  230  14  7   8.5   4.6 |   2.9  37.2  250  19 10   9.2   5.0
 15000   3.2  37.8  225  13  7   8.4   4.6 |   4.3  39.7  245  18  9   9.1   5.0
 14500   4.4  39.9  220  12  6   9.4   5.1 |   5.7  42.3  245  17  9   9.6   5.3
 14000   5.8  42.4  220  11  5   9.8   5.4 |   7.1  44.8  245  16  8   9.8   5.4
 13500   7.3  45.1  215   9  5  10.0   5.5 |   8.6  47.5  240  15  8   9.7   5.3
 13000   8.8  47.8  215   9  5  10.3   5.7 |  10.0  50.0  240  14  7   9.4   5.2
 12500  10.3  50.5  215   9  5  10.2   5.6 |  11.4  52.5  235  14  7   9.3   5.1
 12000  11.8  53.2  215   8  4   9.6   5.3 |  12.8  55.0  235  13  6   8.9   4.9
 11500  13.2  55.8  215   8  4   9.6   5.3 |  14.1  57.4  230  11  6   8.9   4.9
 11000  14.5  58.1  215   7  4   8.2   4.5 |  15.3  59.5  230  10  5   7.9   4.4
 10500  15.7  60.3  215   6  3  11.4   6.3 |  16.5  61.7  225   9  5  10.0   5.5
 10250  16.6  61.9  215   5  3  12.4   6.8 |  17.3  63.1  225   8  4  10.5   5.7
 10000  17.3  63.1  215   5  2   8.9   4.9 |  17.9  64.2  225   7  3   8.1   4.4
  9750  18.0  64.4  210   4  2   9.9   5.4 |  18.6  65.5  225   5  3   8.7   4.8
  9500  18.8  65.8  210   4  2   9.4   5.2 |  19.2  66.6  230   4  2   8.5   4.7
  9250  19.4  66.9  210   4  2   9.3   5.1 |  19.8  67.6  230   3  2   9.1   5.0
  9000  20.1  68.2  210   4  2   9.8   5.4 |  20.5  68.9  245   3  1   9.5   5.2
  8750  20.9  69.6  210   4  2  10.0   5.5 |  21.2  70.2  255   2  1   9.3   5.1
  8500  21.6  70.9  210   4  2  10.0   5.5 |  21.9  71.4  270   2  1   9.3   5.1
  8250  22.4  72.3  215   3  2  10.8   5.9 |  22.6  72.7  290   2  1  10.9   6.0
  8000  23.2  73.8  215   3  2  10.2   5.6 |  23.5  74.3  295   2  1  10.7   5.9
  7750  23.9  75.0  215   3  2   9.1   5.0 |  24.2  75.6  295   2  1   9.3   5.1
  7500  24.6  76.3  215   3  2   9.7   5.3 |  24.9  76.8  300   3  1   9.7   5.3
  7250  25.4  77.7  215   3  2  10.5   5.8 |  25.6  78.1  300   3  1   9.6   5.3
  7000  26.2  79.2  220   3  2  10.5   5.8 |  26.3  79.3  305   3  2   9.8   5.4
  6750  26.9  80.4  220   3  1   9.5   5.2 |  27.1  80.8  310   3  2  10.2   5.6
  6500  27.6  81.7  220   3  1   9.9   5.4 |  27.8  82.0  310   3  2  10.1   5.6
  6250  28.4  83.1  225   3  1  10.9   6.0 |  28.6  83.5  310   3  2   9.8   5.4
  6000  29.2  84.6  225   3  1  10.9   6.0 |  29.3  84.7  310   3  2   9.9   5.4
  5750  30.0  86.0  230   3  1  10.5   5.7 |  30.1  86.2  310   4  2   9.6   5.2
  5500  30.9  87.6  235   2  1  16.5   9.0 |  30.8  87.4  310   4  2  12.1   6.6
________________________________________________________________________________

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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