Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 041250
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0650 MDT Tuesday, August 4, 2015

This forecast is for Tuesday, August 4, 2015:

If the trigger temperature of 80.1 F/26.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 905 ft/min (4.6 m/s)
   Maximum height of thermals.................. 16647 ft MSL (11362 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12797 ft MSL (7512 ft AGL)
Thermal soaring outlook for Wednesday 08/05.... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving
Height of stable layer (12-18K ft MSL)......... 16830 ft MSL (11545 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 17322 ft MSL (12037 ft AGL)
Wave soaring outlook for Wednesday 08/05....... Fair

Remarks...

Sunrise/Sunset.................... 06:01:02 / 20:10:28 MDT
Total possible sunshine........... 14 hr 9 min 26 sec (849 min 26 sec)
Altitude of sun at 13:05:30 MDT... 67.38 degrees

Upper air data from rawinsonde observation taken on 08/04/2015 at 0600 MDT

Freezing level.................. 15447 ft MSL (10162 ft AGL)
Convective condensation level... 17989 ft MSL (12704 ft AGL)
Lifted condensation level....... 17062 ft MSL (11777 ft AGL)
Lifted index.................... -2.1
K index......................... +17.4

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  -67.3 -89.1   240   32   16   4.5   2.5   80.0 175.9    27.9      M    M
 45000  -56.2 -69.2   265   60   31  -2.1  -1.1   74.2 165.6    26.3      M    M
 40000  -48.7 -55.7   245   24   12   5.6   3.1   62.0 143.7    20.0      M    M
 38000  -45.6 -50.1   280   36   18   0.7   0.4   58.0 136.4    17.7      M    M
 36000  -46.0 -50.8   260   35   18   8.8   4.9   49.0 120.2    11.8      M    M
 34000  -40.8 -41.4   265   38   19   9.0   4.9   48.1 118.6    11.5      M    M
 32000  -35.9 -32.6   270   41   21   7.4   4.1   46.9 116.4    10.8      M    M
 30000  -31.4 -24.5   270   39   20   8.4   4.6   45.1 113.2     9.8      M    M
 29000  -28.8 -19.8   270   38   20   8.5   4.6   44.6 112.2     9.5      M    M
 28000  -26.2 -15.2   275   38   19   6.8   3.7   43.3 109.9     8.6      M    M
 27000  -24.3 -11.7   275   36   19   6.0   3.3   42.0 107.6     7.6      M    M
 26000  -22.7  -8.9   265   29   15   5.6   3.1   40.4 104.7     6.5      M    M
 25000  -20.6  -5.1   255   23   12   8.6   4.7   39.3 102.8     5.7      M    M
 24000  -18.2  -0.8   250   20   10   7.6   4.2   38.7 101.7     5.2      M    M
 23000  -16.0   3.2   290   21   11   7.8   4.3   37.9 100.3     4.6      M    M
 22000  -13.4   7.9   285   21   11   8.7   4.8   37.4  99.4     4.2      M    M
 21000  -10.8  12.6   285   22   11   8.7   4.8   37.0  98.7     4.0      M    M
 20000   -8.2  17.2   280   22   11   8.9   4.9   36.8  98.2     3.8      M    M
 19500   -7.0  19.4   280   23   12   8.2   4.5   36.5  97.7     3.5      M    M
 19000   -5.7  21.7   280   23   12   8.0   4.4   36.3  97.4     3.4      M    M
 18500   -4.6  23.7   280   25   13   7.5   4.1   35.9  96.7     3.1      M    M
 18000   -3.5  25.7   280   26   13   7.4   4.1   35.6  96.0     2.7      M    M
 17500   -2.4  27.7   285   29   15   4.3   2.4   35.1  95.1     2.3      M    M
 17000   -1.7  28.9   285   33   17   6.3   3.5   34.2  93.5     1.6      M    M
 16500   -2.2  28.0   290   37   19  -2.9  -1.6   32.2  90.0    -0.4   1008  5.1
 16000   -1.5  29.3   290   41   21   6.4   3.5   31.4  88.4    -1.2    973  4.9
 15500   -0.4  31.3   290   41   21   8.8   4.8   31.0  87.9    -1.5    924  4.7
 15000    0.8  33.4   290   40   20   8.5   4.6   30.9  87.6    -1.7    872  4.4
 14500    2.0  35.6   285   39   20   8.0   4.4   30.6  87.1    -2.0    821  4.2
 14000    3.8  38.8   285   36   19   8.0   4.4   30.2  86.3    -2.4    745  3.8
 13500    5.0  41.0   285   33   17   8.0   4.4   29.9  85.7    -2.7    695  3.5
 13000    6.2  43.2   280   30   16   8.0   4.4   29.6  85.2    -2.9    644  3.3
 12500    7.4  45.3   280   27   14   7.5   4.1   29.3  84.7    -3.3    596  3.0
 12000    8.4  47.1   275   25   13   7.6   4.2   28.9  84.1    -3.7    548  2.8
 11500    9.5  49.1   270   23   12   7.7   4.2   28.6  83.4    -4.1    501  2.5
 11000   10.6  51.1   270   21   11   7.7   4.2   28.2  82.8    -4.5    454  2.3
 10500   11.7  53.1   265   19   10   8.2   4.5   27.9  82.3    -4.9    407  2.1
 10250   12.3  54.1   265   18    9   9.0   4.9   27.8  82.1    -5.0    381  1.9
 10000   13.0  55.4   270   17    9   9.1   5.0   27.8  82.0    -5.1    353  1.8
  9750   13.7  56.7   270   17    9   9.1   5.0   27.7  81.9    -5.1    326  1.7
  9500   14.3  57.7   275   17    9   9.1   5.0   27.7  81.8    -5.2    298  1.5
  9250   15.0  59.0   275   16    8   9.1   5.0   27.6  81.7    -5.3    271  1.4
  9000   15.7  60.3   280   16    8   9.2   5.1   27.6  81.6    -5.3    243  1.2
  8750   16.3  61.3   285   15    8   8.6   4.7   27.5  81.5    -5.4    216  1.1
  8500   16.9  62.4   290   15    8   7.4   4.0   27.4  81.3    -5.6    191  1.0
  8250   17.4  63.3   295   14    7   7.1   3.9   27.2  80.9    -5.8    169  0.9
  8000   17.9  64.2   300   14    7   7.2   3.9   27.0  80.6    -6.0    146  0.7
  7750   18.4  65.1   300   15    8   7.1   3.9   26.8  80.2    -6.3    124  0.6
  7500   18.9  66.0   305   15    8   7.2   3.9   26.6  79.8    -6.5    101  0.5
  7250   19.4  66.9   305   16    8   7.1   3.9   26.4  79.5    -6.8     78  0.4
  7000   19.9  67.8   305   17    9   7.4   4.1   26.2  79.1    -7.0     56  0.3
  6750   20.5  68.9   295   14    7   6.4   3.5   26.0  78.8    -7.2     33  0.2
  6500   20.7  69.3   280   11    6  -0.0  -0.0   25.5  78.0    -7.8     18  0.1
  6250   20.4  68.7   260    9    5  -4.2  -2.3   24.6  76.2    -8.8     20  0.1
  6000   20.1  68.2   230    9    5  -1.9  -1.0   23.6  74.5    -9.9     22  0.1
  5750   19.8  67.6   220    8    4  -6.7  -3.7   22.6  72.7   -10.9     24  0.1
  5500   18.6  65.5   205    7    4 -24.3 -13.4   20.8  69.4   -12.9     53  0.3

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

           08/04/2015 at 0900 MDT          |       08/04/2015 at 1200 MDT
                                           |
K index... +15.4  LI... -0.8               | K index... +8.6  LI... -1.3
CAPE... +50.4  CIN... -181.8               | CAPE... +226.9  CIN... -71.0
                                           |
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 -61.5 -78.7  260  25 13   3.3   1.8 | -60.4 -76.7  250  23 12   3.0   1.6
 45000 -56.5 -69.7  265  36 18   3.4   1.9 | -56.5 -69.7  255  33 17   1.7   0.9
 40000 -51.2 -60.2  280  35 18   5.0   2.7 | -53.5 -64.3  295  37 19   6.3   3.5
 38000 -48.3 -54.9  275  35 18   4.9   2.7 | -49.8 -57.6  290  38 20   6.1   3.4
 36000 -45.0 -49.0  275  35 18   4.7   2.6 | -45.7 -50.3  290  40 20   6.0   3.3
 34000 -40.9 -41.6  275  34 17   6.9   3.8 | -41.1 -42.0  290  38 20   7.8   4.3
 32000 -36.8 -34.2  275  33 17   6.8   3.7 | -36.5 -33.7  290  36 18   7.6   4.2
 30000 -31.9 -25.4  280  33 17   8.4   4.6 | -31.5 -24.7  295  35 18   8.4   4.6
 29000 -29.4 -20.9  280  34 17   8.4   4.6 | -29.0 -20.2  295  34 18   8.4   4.6
 28000 -26.9 -16.4  280  34 18   7.9   4.3 | -26.5 -15.7  295  34 17   7.7   4.2
 27000 -24.6 -12.3  280  32 17   7.5   4.1 | -24.3 -11.7  295  33 17   7.2   4.0
 26000 -22.4  -8.3  280  30 16   7.5   4.1 | -22.1  -7.8  295  33 17   7.2   4.0
 25000 -20.2  -4.4  280  28 14   7.5   4.1 | -19.9  -3.8  290  32 16   7.3   4.0
 24000 -18.1  -0.6  275  26 13   6.8   3.7 | -18.0  -0.4  290  31 16   6.5   3.6
 23000 -16.1   3.0  270  24 12   6.8   3.7 | -16.0   3.2  285  29 15   6.5   3.6
 22000 -14.1   6.6  260  23 12   6.9   3.8 | -14.1   6.6  275  28 14   6.6   3.6
 21000 -12.1  10.2  255  21 11   6.7   3.7 | -12.0  10.4  275  25 13   7.2   4.0
 20000 -10.1  13.8  245  19 10   6.7   3.7 |  -9.8  14.4  270  22 11   7.2   4.0
 19500  -9.1  15.6  245  18  9   6.7   3.7 |  -8.7  16.3  270  20 10   7.1   3.9
 19000  -8.1  17.4  240  17  9   7.1   3.9 |  -7.5  18.5  270  19 10   8.8   4.8
 18500  -6.6  20.1  240  15  8   7.2   3.9 |  -5.5  22.1  275  18  9   9.0   4.9
 18000  -5.5  22.1  245  14  7   7.9   4.3 |  -4.1  24.6  280  18  9   8.9   4.9
 17500  -4.3  24.3  250  13  7   8.1   4.4 |  -2.8  27.0  285  19 10   8.8   4.8
 17000  -3.1  26.4  255  12  6   8.4   4.6 |  -1.5  29.3  290  21 11   8.4   4.6
 16500  -1.7  28.9  265  12  6   9.5   5.2 |  -0.4  31.3  290  24 12   6.9   3.8
 16000  -0.3  31.5  270  13  7   9.5   5.2 |   0.7  33.3  295  27 14   7.1   3.9
 15500   1.1  34.0  280  14  7   8.3   4.6 |   1.6  34.9  295  31 16   5.9   3.3
 15000   2.4  36.3  285  17  9   8.4   4.6 |   2.5  36.5  295  34 17   6.1   3.3
 14500   3.6  38.5  290  20 10   7.5   4.1 |   3.3  37.9  295  36 19   5.6   3.0
 14000   4.6  40.3  295  24 12   7.1   3.9 |   4.0  39.2  295  38 19   5.5   3.0
 13500   5.7  42.3  295  28 14   6.9   3.8 |   4.7  40.5  290  39 20   5.9   3.3
 13000   6.6  43.9  295  31 16   6.7   3.7 |   5.5  41.9  290  37 19   6.4   3.5
 12500   7.5  45.5  295  34 18   6.7   3.7 |   6.3  43.3  285  34 18   7.1   3.9
 12000   8.3  46.9  295  35 18   6.2   3.4 |   7.4  45.3  285  31 16   8.4   4.6
 11500   9.2  48.6  295  36 19   6.4   3.5 |   8.6  47.5  285  28 15   8.4   4.6
 11000  10.1  50.2  295  34 18   6.9   3.8 |   9.8  49.6  285  25 13   8.4   4.6
 10500  11.0  51.8  295  32 16   4.0   2.2 |  11.1  52.0  285  22 11   5.7   3.1
 10250  11.2  52.2  290  31 16   4.8   2.6 |  11.4  52.5  285  21 11   6.6   3.6
 10000  11.8  53.2  290  29 15   9.7   5.3 |  12.1  53.8  280  19 10  10.9   6.0
  9750  12.4  54.3  290  27 14   9.0   4.9 |  12.8  55.0  280  16  8  10.0   5.5
  9500  13.1  55.6  290  24 13   8.5   4.6 |  13.6  56.5  280  13  7   9.3   5.1
  9250  13.6  56.5  290  22 12   6.6   3.6 |  14.2  57.6  275  11  6   7.7   4.2
  9000  14.1  57.4  290  21 11   7.7   4.2 |  14.8  58.6  275  10  5   9.5   5.2
  8750  14.8  58.6  290  18  9   9.2   5.1 |  15.5  59.9  275   9  5  10.8   5.9
  8500  15.4  59.7  290  16  8   8.2   4.5 |  16.3  61.3  270   8  4  10.3   5.6
  8250  16.0  60.8  290  14  7   7.1   3.9 |  17.1  62.8  270   8  4  10.2   5.6
  8000  16.5  61.7  290  12  6   7.1   3.9 |  17.8  64.0  270   7  4   9.9   5.4
  7750  17.1  62.8  285  10  5   7.1   3.9 |  18.5  65.3  270   7  4   9.3   5.1
  7500  17.6  63.7  285   8  4   8.0   4.4 |  19.3  66.7  270   7  4  10.0   5.5
  7250  18.2  64.8  285   7  3   9.1   5.0 |  20.0  68.0  270   7  4  10.7   5.9
  7000  18.9  66.0  285   5  3   8.7   4.7 |  20.8  69.4  270   7  3  10.1   5.5
  6750  19.5  67.1  280   4  2   7.7   4.2 |  21.5  70.7  270   7  3   9.4   5.1
  6500  20.0  68.0  275   3  1   6.9   3.8 |  22.3  72.1  270   6  3  10.4   5.7
  6250  20.5  68.9  265   2  1   7.4   4.0 |  23.1  73.6  270   6  3  12.0   6.6
  6000  21.0  69.8  250   2  1   5.8   3.2 |  23.9  75.0  270   6  3   9.6   5.3
  5750  21.4  70.5  215   2  1   7.4   4.1 |  24.7  76.5  270   6  3  13.8   7.5
  5500  22.1  71.8  200   2  1  16.0   8.8 |  26.2  79.2  270   6  3  27.9  15.3

           08/04/2015 at 1500 MDT          |       08/04/2015 at 1800 MDT
                                           |
K index... +12.3  LI... +0.5               | K index... +15.8  LI... +0.1
CAPE... +72.6  CIN... -61.1                | CAPE... 0.0  CIN... -0.7
                                           |
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 -61.0 -77.8  270  22 11   2.7   1.5 | -62.3 -80.1  265  19 10   1.7   0.9
 45000 -57.2 -71.0  280  36 19   2.3   1.3 | -59.1 -74.4  280  32 17   3.3   1.8
 40000 -52.9 -63.2  300  44 23   5.9   3.2 | -53.2 -63.8  295  40 21   6.8   3.7
 38000 -49.3 -56.7  295  46 24   6.0   3.3 | -49.1 -56.4  295  42 22   6.8   3.7
 36000 -45.7 -50.3  290  48 25   5.7   3.1 | -45.1 -49.2  295  43 22   6.7   3.7
 34000 -41.0 -41.8  295  47 24   8.1   4.4 | -40.4 -40.7  290  41 21   7.9   4.4
 32000 -36.2 -33.2  300  46 24   8.1   4.4 | -35.6 -32.1  285  38 20   7.9   4.3
 30000 -30.8 -23.4  300  40 21   8.0   4.4 | -30.6 -23.1  290  33 17   8.5   4.7
 29000 -28.4 -19.1  300  37 19   8.0   4.4 | -27.4 -17.3  290  30 15   8.5   4.7
 28000 -26.1 -15.0  300  35 18   7.6   4.2 | -24.9 -12.8  295  28 14   7.7   4.2
 27000 -23.8 -10.8  300  32 17   7.6   4.2 | -22.6  -8.7  295  29 15   7.8   4.3
 26000 -21.6  -6.9  300  30 15   7.6   4.2 | -20.3  -4.5  300  31 16   7.8   4.3
 25000 -19.3  -2.7  295  28 14   7.7   4.2 | -17.9  -0.2  300  32 17   7.2   4.0
 24000 -17.0   1.4  295  27 14   7.8   4.3 | -16.1   3.0  300  30 16   6.2   3.4
 23000 -14.6   5.7  295  27 14   7.8   4.3 | -14.3   6.3  300  28 14   6.2   3.4
 22000 -12.3   9.9  295  27 14   7.5   4.1 | -12.4   9.7  300  26 13   6.3   3.5
 21000 -10.1  13.8  300  28 14   7.1   3.9 | -10.5  13.1  300  27 14   6.3   3.5
 20000  -8.0  17.6  300  29 15   7.1   3.9 |  -8.6  16.5  300  29 15   6.3   3.5
 19500  -6.9  19.6  305  29 15   7.1   3.9 |  -7.7  18.1  300  30 15   6.3   3.4
 19000  -5.9  21.4  305  30 16   6.9   3.8 |  -6.7  19.9  300  31 16   7.4   4.1
 18500  -4.9  23.2  305  32 16   6.9   3.8 |  -5.6  21.9  300  32 16   7.3   4.0
 18000  -3.9  25.0  305  33 17   6.7   3.7 |  -4.5  23.9  300  33 17   7.3   4.0
 17500  -2.9  26.8  305  34 18   6.4   3.5 |  -3.4  25.9  300  34 17   7.3   4.0
 17000  -1.9  28.6  305  36 18   6.4   3.5 |  -2.3  27.9  300  34 18   7.2   4.0
 16500  -1.0  30.2  305  37 19   6.7   3.7 |  -1.2  29.8  300  34 18   7.8   4.3
 16000  -0.0  32.0  300  38 19   6.7   3.7 |  -0.1  31.8  300  35 18   7.8   4.3
 15500   1.4  34.5  300  38 20   6.6   3.6 |   1.6  34.9  295  35 18   8.4   4.6
 15000   2.3  36.1  295  37 19   6.9   3.8 |   2.8  37.0  295  34 17   8.6   4.7
 14500   3.2  37.8  290  36 19   7.3   4.0 |   4.0  39.2  290  32 17   8.9   4.9
 14000   4.1  39.4  290  33 17   7.5   4.1 |   5.2  41.4  290  30 15   9.0   4.9
 13500   5.1  41.2  285  30 15   8.6   4.7 |   6.4  43.5  290  28 14   9.3   5.1
 13000   6.4  43.5  285  27 14   9.2   5.0 |   7.8  46.0  290  26 14   9.4   5.2
 12500   7.7  45.9  285  23 12   9.5   5.2 |   9.2  48.6  290  25 13   9.5   5.2
 12000   9.2  48.6  285  22 11   9.8   5.4 |  10.6  51.1  290  24 12   9.6   5.3
 11500  10.6  51.1  285  20 11   9.7   5.3 |  12.0  53.6  295  22 12   9.5   5.2
 11000  12.0  53.6  285  20 10   9.3   5.1 |  13.4  56.1  295  21 11   9.2   5.1
 10500  13.5  56.3  285  19 10   5.5   3.0 |  14.9  58.8  300  20 10   5.7   3.1
 10250  13.7  56.7  285  19 10   6.9   3.8 |  15.1  59.2  300  19 10   6.9   3.8
 10000  14.6  58.3  285  19 10  13.0   7.1 |  16.0  60.8  300  19 10  12.3   6.8
  9750  15.5  59.9  285  18  9  11.8   6.5 |  16.8  62.2  300  18  9  11.3   6.2
  9500  16.4  61.5  285  18  9  10.3   5.7 |  17.6  63.7  305  17  9   9.9   5.4
  9250  17.0  62.6  285  18  9   8.5   4.7 |  18.3  64.9  305  17  9   8.5   4.6
  9000  17.7  63.9  285  18  9  10.4   5.7 |  19.0  66.2  305  17  9  10.2   5.6
  8750  18.5  65.3  285  17  9  11.1   6.1 |  19.8  67.6  305  16  8  10.6   5.8
  8500  19.3  66.7  285  17  9  10.6   5.8 |  20.5  68.9  305  16  8  10.4   5.7
  8250  20.1  68.2  285  17  9  10.1   5.6 |  21.3  70.3  305  16  8  10.3   5.7
  8000  20.8  69.4  285  17  9  10.0   5.5 |  22.1  71.8  310  16  8   9.8   5.4
  7750  21.6  70.9  285  17  9   9.8   5.4 |  22.8  73.0  310  16  8   9.2   5.0
  7500  22.3  72.1  285  16  8   9.9   5.4 |  23.5  74.3  310  15  8   9.9   5.4
  7250  23.1  73.6  285  16  8  10.0   5.5 |  24.3  75.7  310  15  8  10.6   5.8
  7000  23.8  74.8  285  16  8   9.9   5.5 |  25.1  77.2  310  15  8  10.1   5.5
  6750  24.6  76.3  285  16  8  10.1   5.5 |  25.8  78.4  310  15  8   9.5   5.2
  6500  25.4  77.7  285  15  8  10.7   5.8 |  26.5  79.7  310  14  7  10.3   5.6
  6250  26.2  79.2  290  15  8  11.4   6.3 |  27.3  81.1  315  14  7  11.2   6.1
  6000  27.0  80.6  290  14  7   9.9   5.4 |  28.1  82.6  315  14  7  10.2   5.6
  5750  27.8  82.0  290  14  7  14.5   7.9 |  28.8  83.8  315  13  7  10.9   6.0
  5500  29.3  84.7  290  13  7  27.6  15.2 |  29.8  85.6  315  12  6  15.6   8.6
________________________________________________________________________________

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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