Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 270031
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1830 MDT Sunday, July 26, 2015

This forecast is for Monday, July 27, 2015:

If the trigger temperature of 84.4 F/29.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1316 ft/min (6.7 m/s)
   Maximum height of thermals.................. 19642 ft MSL (14335 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 15017 ft MSL (9711 ft AGL)
Thermal soaring outlook for Tuesday 07/28...... Excellent

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)................ Neither
Potential height of wave....................... 17878 ft MSL (12571 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 numerical model forecast valid on 07/27/2015 at 0600 MDT

Freezing level.................. 16541 ft MSL (11234 ft AGL)
Convective condensation level... 15680 ft MSL (10373 ft AGL)
Lifted condensation level....... 16952 ft MSL (11645 ft AGL)
Lifted index.................... -5.1
K index......................... +22.4

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  -66.6 -87.9   225   31   16   1.5   0.8      M     M       M      M    M
 45000  -61.5 -78.7   225   44   23   7.1   3.9      M     M       M      M    M
 40000  -50.6 -59.1   220   47   24   7.8   4.3      M     M       M      M    M
 38000  -45.9 -50.6   220   46   24   7.8   4.3      M     M       M      M    M
 36000  -41.2 -42.2   225   46   24   7.8   4.3      M     M       M      M    M
 34000  -36.1 -33.0   230   45   23   7.6   4.2      M     M       M      M    M
 32000  -31.5 -24.7   230   45   23   7.8   4.3      M     M       M      M    M
 30000  -27.1 -16.8   235   43   22   7.3   4.0   49.1 120.4     9.9      M    M
 29000  -24.9 -12.8   235   42   22   7.3   4.0   48.2 118.8     9.3      M    M
 28000  -22.8  -9.0   235   41   21   5.6   3.1   47.3 117.2     8.7      M    M
 27000  -21.3  -6.3   235   41   21   5.2   2.9   45.4 113.8     7.3      M    M
 26000  -19.8  -3.6   240   40   21   5.4   2.9   43.7 110.7     6.0      M    M
 25000  -18.3  -0.9   240   40   20   5.6   3.1   42.2 108.0     4.7      M    M
 24000  -16.3   2.7   240   36   18   7.1   3.9   41.1 106.0     3.8      M    M
 23000  -14.1   6.6   245   31   16   7.1   3.9   40.1 104.2     3.0      M    M
 22000  -12.0  10.4   250   26   14   7.0   3.9   39.2 102.6     2.3      M    M
 21000  -10.0  14.0   245   21   11   6.9   3.8   38.1 100.6     1.3      M    M
 20000   -8.0  17.6   240   15    8   6.9   3.8   37.1  98.8     0.4      M    M
 19500   -7.0  19.4   230   13    7   6.9   3.8   36.7  98.0    -0.0   1313  6.7
 19000   -6.0  21.2   225   11    6   7.7   4.2   36.2  97.2    -0.4   1267  6.4
 18500   -4.8  23.4   225   11    6   7.8   4.3   35.9  96.6    -0.7   1217  6.2
 18000   -3.1  26.4   225   10    5   7.5   4.1   35.4  95.7    -1.2   1143  5.8
 17500   -2.0  28.4   230   10    5   7.5   4.1   35.0  95.0    -1.5   1094  5.6
 17000   -0.8  30.6   235    9    5   7.6   4.2   34.6  94.3    -1.9   1046  5.3
 16500    0.3  32.5   240    9    5   8.1   4.5   34.3  93.7    -2.2    996  5.1
 16000    1.5  34.7   245    9    5   8.1   4.4   34.0  93.2    -2.5    945  4.8
 15500    2.7  36.9   250    9    5   8.2   4.5   33.8  92.8    -2.8    895  4.5
 15000    3.9  39.0   255    9    5   8.2   4.5   33.5  92.3    -3.1    845  4.3
 14500    5.1  41.2   255   10    5   8.3   4.6   33.2  91.8    -3.3    794  4.0
 14000    6.3  43.3   255   10    5   8.3   4.6   33.0  91.4    -3.6    743  3.8
 13500    7.5  45.5   255   10    5   8.4   4.6   32.8  91.0    -3.9    692  3.5
 13000    8.7  47.7   255   11    5   8.3   4.6   32.5  90.6    -4.1    640  3.3
 12500   10.0  50.0   255   11    6   8.3   4.6   32.3  90.2    -4.4    589  3.0
 12000   11.2  52.2   255   11    5   8.4   4.6   32.1  89.8    -4.7    537  2.7
 11500   12.4  54.3   255   11    5   8.4   4.6   31.9  89.4    -4.9    486  2.5
 11000   13.6  56.5   255   10    5   7.4   4.0   31.6  88.9    -5.3    437  2.2
 10500   14.7  58.5   255   10    5   4.3   2.3   31.3  88.3    -5.6    388  2.0
 10250   14.9  58.8   255   10    5   4.7   2.6   30.7  87.3    -6.2    375  1.9
 10000   15.5  59.9   255    9    5   9.4   5.1   30.6  87.1    -6.3    350  1.8
  9750   16.1  61.0   250    9    5   8.1   4.5   30.5  86.9    -6.5    324  1.6
  9500   16.7  62.1   250    9    4   8.5   4.7   30.4  86.7    -6.6    298  1.5
  9250   17.3  63.1   250    8    4   6.8   3.7   30.2  86.4    -6.8    274  1.4
  9000   17.7  63.9   250    8    4   6.1   3.4   30.0  85.9    -7.1    253  1.3
  8750   18.2  64.8   250    7    4   6.9   3.8   29.7  85.5    -7.3    231  1.2
  8500   18.7  65.7   250    7    3   6.5   3.6   29.5  85.1    -7.6    209  1.1
  8250   19.1  66.4   250    6    3   5.9   3.2   29.2  84.6    -7.9    188  1.0
  8000   19.5  67.1   255    6    3   4.4   2.4   28.9  84.0    -8.3    170  0.9
  7750   19.7  67.5   255    6    3   4.0   2.2   28.4  83.2    -8.8    155  0.8
  7500   20.0  68.0   255    5    3   2.5   1.4   28.0  82.3    -9.3    141  0.7
  7250   19.9  67.8   255    5    3  -0.5  -0.3   27.3  81.1   -10.1    134  0.7
  7000   19.8  67.6   260    5    3  -1.8  -1.0   26.4  79.6   -11.0    132  0.7
  6750   19.6  67.3   265    5    3  -0.4  -0.2   25.6  78.0   -12.0    130  0.7
  6500   19.4  66.9   270    5    3  -5.8  -3.2   24.7  76.5   -12.9    129  0.7
  6250   18.5  65.3   275    5    3 -11.6  -6.3   23.2  73.7   -14.5    147  0.7
  6000   17.6  63.7   280    5    3 -10.4  -5.7   21.6  71.0   -16.2    166  0.8
  5750   16.8  62.2   285    6    3 -10.1  -5.6   20.1  68.2   -17.8    185  0.9
  5500   15.9  60.6   280    5    3 -10.3  -5.7   18.7  65.6   -19.5    204  1.0

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

           07/27/2015 at 0900 MDT          |       07/27/2015 at 1200 MDT
                                           |
K index... +24.6  LI... -0.3               | K index... +26.6  LI... -3.6
CAPE... +25.6  CIN... -385.4               | CAPE... +633.1  CIN... -54.3
                                           |
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 -65.7 -86.3  215  31 16   0.6   0.3 | -65.5 -85.9  220  35 18   0.3   0.2
 45000 -61.7 -79.1  220  44 22   6.9   3.8 | -61.8 -79.2  220  47 24   6.9   3.8
 40000 -51.1 -60.0  220  44 23   7.8   4.3 | -51.3 -60.3  220  48 25   7.6   4.2
 38000 -46.4 -51.5  220  44 23   7.8   4.3 | -46.8 -52.2  225  49 25   7.6   4.2
 36000 -41.1 -42.0  225  45 23   7.6   4.2 | -42.2 -44.0  225  50 26   7.6   4.2
 34000 -36.6 -33.9  230  44 23   7.5   4.1 | -37.1 -34.8  225  49 25   7.5   4.1
 32000 -32.1 -25.8  230  44 22   7.7   4.2 | -32.6 -26.7  230  47 24   8.0   4.4
 30000 -27.6 -17.7  230  42 21   7.4   4.1 | -28.1 -18.6  230  45 23   7.6   4.1
 29000 -25.4 -13.7  230  41 21   7.4   4.1 | -25.8 -14.4  230  44 23   7.6   4.2
 28000 -23.3  -9.9  235  40 20   6.2   3.4 | -23.6 -10.5  230  43 22   6.5   3.6
 27000 -21.5  -6.7  235  39 20   6.0   3.3 | -21.8  -7.2  230  43 22   6.3   3.5
 26000 -19.8  -3.6  235  39 20   6.2   3.4 | -19.9  -3.8  230  42 22   6.4   3.5
 25000 -18.0  -0.4  235  38 20   6.4   3.5 | -18.1  -0.6  230  42 21   6.6   3.6
 24000 -16.1   3.0  235  36 19   6.7   3.7 | -16.0   3.2  230  39 20   7.1   3.9
 23000 -14.1   6.6  235  33 17   6.7   3.7 | -13.9   7.0  230  36 19   7.1   3.9
 22000 -12.1  10.2  240  31 16   6.8   3.7 | -11.9  10.6  230  33 17   7.0   3.8
 21000 -10.0  14.0  235  26 13   7.3   4.0 | -10.0  14.0  235  30 15   6.2   3.4
 20000  -7.9  17.8  230  21 11   7.3   4.0 |  -8.1  17.4  235  27 14   6.2   3.4
 19500  -6.8  19.8  225  19 10   7.3   4.0 |  -7.2  19.0  240  25 13   6.1   3.4
 19000  -5.7  21.7  225  17  9   7.9   4.3 |  -6.2  20.8  240  24 12   7.9   4.4
 18500  -4.5  23.9  230  17  9   8.0   4.4 |  -5.0  23.0  235  24 12   8.1   4.4
 18000  -2.8  27.0  230  18  9   7.5   4.1 |  -3.3  26.1  230  23 12   7.4   4.0
 17500  -1.7  28.9  230  17  9   7.4   4.1 |  -2.2  28.0  230  22 11   7.3   4.0
 17000  -0.6  30.9  225  16  8   7.5   4.1 |  -1.1  30.0  230  21 11   7.5   4.1
 16500   0.6  33.1  225  16  8   7.7   4.2 |   0.1  32.2  230  20 10   8.2   4.5
 16000   1.7  35.1  230  15  8   7.8   4.3 |   1.3  34.3  235  19 10   8.1   4.4
 15500   2.8  37.0  230  15  8   7.3   4.0 |   2.5  36.5  235  18  9   8.6   4.7
 15000   3.9  39.0  235  14  7   7.3   4.0 |   3.7  38.7  235  18  9   8.6   4.7
 14500   5.0  41.0  235  13  7   7.8   4.3 |   5.0  41.0  240  18  9   8.7   4.8
 14000   6.2  43.2  240  12  6   8.0   4.4 |   6.3  43.3  245  17  9   8.8   4.8
 13500   7.4  45.3  240  12  6   8.0   4.4 |   7.6  45.7  255  17  9   8.9   4.9
 13000   8.5  47.3  250  11  6   7.9   4.3 |   9.0  48.2  255  16  8   9.0   5.0
 12500   9.7  49.5  255  10  5   8.0   4.4 |  10.3  50.5  255  15  8   9.1   5.0
 12000  10.9  51.6  260  10  5   9.0   4.9 |  11.6  52.9  255  15  8   9.2   5.1
 11500  12.2  54.0  270  10  5   8.9   4.9 |  13.0  55.4  260  15  8   9.1   5.0
 11000  13.4  56.1  275  11  6   7.9   4.3 |  14.1  57.4  260  16  8   7.1   3.9
 10500  14.5  58.1  280  12  6  10.8   5.9 |  15.1  59.2  260  16  8   9.7   5.3
 10250  15.4  59.7  280  13  7  11.0   6.0 |  15.9  60.6  260  15  8  10.9   6.0
 10000  16.0  60.8  280  13  7   7.3   4.0 |  16.6  61.9  260  15  8   8.5   4.7
  9750  16.6  61.9  280  14  7   8.3   4.5 |  17.2  63.0  260  14  7   9.2   5.1
  9500  17.2  63.0  280  14  7   8.0   4.4 |  17.9  64.2  260  13  7   8.8   4.8
  9250  17.8  64.0  280  14  7   7.4   4.1 |  18.5  65.3  260  13  7   7.8   4.3
  9000  18.3  64.9  280  14  7   7.3   4.0 |  19.0  66.2  260  12  6   7.9   4.3
  8750  18.9  66.0  285  14  7   7.8   4.3 |  19.6  67.3  255  11  6   8.5   4.7
  8500  19.4  66.9  285  13  7   7.4   4.1 |  20.3  68.5  255  10  5   8.2   4.5
  8250  19.9  67.8  285  13  7   5.9   3.2 |  20.9  69.6  250   9  4   8.7   4.8
  8000  20.3  68.5  285  12  6   4.6   2.5 |  21.5  70.7  245   7  4   7.1   3.9
  7750  20.6  69.1  285  11  6   5.0   2.7 |  21.9  71.4  235   6  3   5.4   3.0
  7500  20.9  69.6  285  10  5   3.6   2.0 |  22.3  72.1  225   5  3   6.5   3.5
  7250  21.1  70.0  285   9  5   0.9   0.5 |  22.8  73.0  205   5  2   7.6   4.1
  7000  21.0  69.8  285   8  4  -0.1  -0.1 |  23.3  73.9  185   4  2   8.5   4.6
  6750  21.0  69.8  285   7  4  -0.1  -0.0 |  23.9  75.0  170   5  2   9.2   5.1
  6500  20.9  69.6  285   7  3  -2.1  -1.2 |  24.5  76.1  160   5  2  10.5   5.7
  6250  20.5  68.9  280   6  3  -3.5  -1.9 |  25.3  77.5  160   5  2  11.5   6.3
  6000  20.2  68.4  280   5  2  -4.1  -2.3 |  26.2  79.2  160   4  2  10.9   6.0
  5750  19.8  67.6  270   3  2  -0.5  -0.3 |  27.0  80.6  155   4  2  11.1   6.1
  5500  20.1  68.2  255   2  1  14.1   7.7 |  28.0  82.4  155   4  2  17.9   9.8

           07/27/2015 at 1500 MDT          |       07/27/2015 at 1800 MDT
                                           |
K index... +31.6  LI... -1.4               | K index... +31.2  LI... -3.1
CAPE... +151.1  CIN... -3.0                | CAPE... +320.0  CIN... -21.2
                                           |
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 -65.1 -85.2  225  38 20  -0.2  -0.1 | -65.1 -85.2  240  40 21  -0.0  -0.0
 45000 -62.0 -79.6  230  53 27   6.7   3.7 | -61.8 -79.2  235  55 28   6.7   3.7
 40000 -51.8 -61.2  225  55 28   7.7   4.2 | -51.4 -60.5  230  57 29   7.8   4.3
 38000 -47.1 -52.8  225  56 29   7.7   4.2 | -46.7 -52.1  225  57 29   7.8   4.3
 36000 -42.5 -44.5  220  57 29   7.7   4.2 | -41.5 -42.7  225  58 30   7.7   4.2
 34000 -37.2 -35.0  225  54 28   7.8   4.3 | -36.9 -34.4  230  54 28   7.6   4.1
 32000 -32.5 -26.5  230  51 26   8.5   4.6 | -32.4 -26.3  235  52 27   7.6   4.2
 30000 -28.1 -18.6  230  48 25   7.4   4.1 | -28.1 -18.6  240  44 22   7.1   3.9
 29000 -25.9 -14.6  235  47 24   7.4   4.1 | -26.0 -14.8  240  39 20   7.1   3.9
 28000 -23.7 -10.7  235  46 24   7.4   4.0 | -23.8 -10.8  245  35 18   7.7   4.2
 27000 -21.5  -6.7  235  44 23   7.4   4.0 | -21.4  -6.5  245  33 17   7.9   4.3
 26000 -19.4  -2.9  235  43 22   7.4   4.1 | -19.1  -2.4  245  31 16   7.9   4.3
 25000 -17.2   1.0  235  41 21   7.3   4.0 | -16.7   1.9  245  29 15   7.6   4.2
 24000 -15.2   4.6  240  38 20   6.7   3.7 | -15.0   5.0  255  31 16   5.2   2.8
 23000 -13.2   8.2  240  35 18   6.7   3.7 | -13.5   7.7  265  35 18   5.2   2.9
 22000 -11.3  11.7  245  31 16   6.7   3.7 | -11.9  10.6  270  39 20   5.4   3.0
 21000  -9.4  15.1  245  28 14   6.5   3.6 | -10.3  13.5  270  37 19   6.1   3.3
 20000  -7.5  18.5  245  24 12   6.5   3.6 |  -8.6  16.5  265  35 18   6.4   3.5
 19500  -6.6  20.1  250  23 12   6.5   3.6 |  -7.7  18.1  265  34 18   6.5   3.6
 19000  -5.6  21.9  250  21 11   6.5   3.6 |  -6.7  19.9  260  33 17   8.9   4.9
 18500  -4.7  23.5  250  20 10   6.5   3.6 |  -5.4  22.3  260  31 16   9.2   5.0
 18000  -3.3  26.1  250  18  9   6.4   3.5 |  -3.5  25.7  260  28 15   9.1   5.0
 17500  -2.4  27.7  245  17  9   6.4   3.5 |  -2.2  28.0  260  26 14   9.0   5.0
 17000  -1.4  29.5  245  17  9   6.5   3.6 |  -0.9  30.4  260  24 12   8.9   4.9
 16500  -0.4  31.3  240  16  8   7.0   3.8 |   0.4  32.7  255  22 12   8.5   4.6
 16000   0.6  33.1  235  15  8   6.9   3.8 |   1.6  34.9  255  21 11   8.5   4.7
 15500   1.6  34.9  230  14  7   8.2   4.5 |   2.8  37.0  255  19 10   8.5   4.6
 15000   2.8  37.0  225  14  7   8.2   4.5 |   4.1  39.4  250  17  9   8.5   4.6
 14500   4.0  39.2  215  13  7   9.4   5.2 |   5.4  41.7  250  15  8   9.1   5.0
 14000   5.5  41.9  215  13  7  10.0   5.5 |   6.8  44.2  250  14  7   9.4   5.2
 13500   7.0  44.6  215  13  7   9.8   5.4 |   8.2  46.8  245  13  7   9.5   5.2
 13000   8.5  47.3  215  12  6   9.6   5.3 |   9.6  49.3  245  12  6   9.5   5.2
 12500   9.9  49.8  215  12  6   9.6   5.3 |  11.0  51.8  245  12  6   9.5   5.2
 12000  11.3  52.3  215  12  6   9.9   5.4 |  12.4  54.3  240  11  5   9.2   5.1
 11500  12.8  55.0  215  12  6   9.8   5.4 |  13.8  56.8  235  10  5   9.2   5.1
 11000  14.2  57.6  215  12  6   8.9   4.9 |  15.0  59.0  230   9  5   7.7   4.2
 10500  15.5  59.9  215  12  6  12.3   6.7 |  16.1  61.0  220   8  4  11.2   6.1
 10250  16.5  61.7  215  12  6  12.8   7.0 |  17.1  62.8  215   7  4  12.5   6.9
 10000  17.3  63.1  220  11  6   8.7   4.8 |  17.8  64.0  215   7  3   8.8   4.8
  9750  18.0  64.4  220  11  6   9.9   5.4 |  18.6  65.5  215   6  3   9.8   5.4
  9500  18.7  65.7  220  11  6   9.3   5.1 |  19.3  66.7  210   6  3   9.3   5.1
  9250  19.4  66.9  220  11  6   9.4   5.1 |  19.9  67.8  210   5  3   9.2   5.0
  9000  20.1  68.2  220  11  6  10.0   5.5 |  20.6  69.1  210   5  2   9.7   5.3
  8750  20.9  69.6  220  11  6  10.2   5.6 |  21.4  70.5  210   5  2  10.0   5.5
  8500  21.7  71.1  220  11  6  10.2   5.6 |  22.1  71.8  215   4  2   9.9   5.5
  8250  22.4  72.3  220  11  6  11.1   6.1 |  22.9  73.2  215   4  2  10.7   5.9
  8000  23.2  73.8  220  11  6  10.1   5.6 |  23.7  74.7  215   4  2   9.9   5.4
  7750  23.9  75.0  220  11  5   8.6   4.7 |  24.4  75.9  215   4  2   8.7   4.8
  7500  24.6  76.3  220  11  5   9.5   5.2 |  25.1  77.2  215   4  2   9.3   5.1
  7250  25.4  77.7  220  10  5  10.8   5.9 |  25.8  78.4  220   4  2  10.6   5.8
  7000  26.2  79.2  220  10  5  10.7   5.9 |  26.6  79.9  220   4  2  10.8   5.9
  6750  26.9  80.4  220  10  5   9.2   5.0 |  27.3  81.1  220   4  2   9.3   5.1
  6500  27.6  81.7  220  10  5   9.7   5.3 |  28.0  82.4  225   3  2   9.7   5.3
  6250  28.4  83.1  220  10  5  10.8   5.9 |  28.8  83.8  225   3  2  10.8   5.9
  6000  29.2  84.6  220   9  5  10.6   5.8 |  29.6  85.3  225   3  2  10.9   6.0
  5750  30.0  86.0  220   9  5  11.1   6.1 |  30.4  86.7  230   3  1   9.8   5.4
  5500  30.9  87.6  220   9  5  17.8   9.8 |  31.1  88.0  235   3  1  10.9   6.0
________________________________________________________________________________

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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