Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 040110
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1910 MDT Monday, August 3, 2015

This forecast is for Tuesday, August 4, 2015:

If the trigger temperature of 75.9 F/24.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 901 ft/min (4.6 m/s)
   Maximum height of thermals.................. 16479 ft MSL (11172 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 0930 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................. 13951 ft MSL (8644 ft AGL)
Thermal soaring outlook for Wednesday 08/05.... 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....................... 14429 ft MSL (9122 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 numerical model forecast valid on 08/04/2015 at 0600 MDT

Freezing level.................. 15964 ft MSL (10657 ft AGL)
Convective condensation level... 15298 ft MSL (9991 ft AGL)
Lifted condensation level....... 16021 ft MSL (10714 ft AGL)
Lifted index.................... -5.6
K index......................... +16.1

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  -62.4 -80.3   255   20   10   2.9   1.6      M     M       M      M    M
 45000  -57.3 -71.1   265   29   15   4.5   2.5      M     M       M      M    M
 40000  -50.5 -58.9   275   35   18   4.5   2.5      M     M       M      M    M
 38000  -47.8 -54.0   275   35   18   4.5   2.5      M     M       M      M    M
 36000  -44.8 -48.6   275   34   18   4.1   2.3      M     M       M      M    M
 34000  -40.6 -41.1   275   34   17   7.3   4.0      M     M       M      M    M
 32000  -36.3 -33.3   275   33   17   7.2   4.0      M     M       M      M    M
 30000  -32.1 -25.8   275   33   17   6.9   3.8   43.6 110.4     8.2      M    M
 29000  -30.1 -22.2   275   34   17   6.9   3.8   42.5 108.4     7.4      M    M
 28000  -28.0 -18.4   275   34   18   6.8   3.8   41.5 106.7     6.8      M    M
 27000  -26.0 -14.8   270   33   17   6.7   3.7   40.2 104.4     5.8      M    M
 26000  -24.0 -11.2   270   32   16   6.8   3.7   39.1 102.3     4.9      M    M
 25000  -22.0  -7.6   265   30   16   6.6   3.6   38.1 100.5     4.2      M    M
 24000  -19.6  -3.3   265   28   15   8.6   4.7   37.4  99.3     3.6      M    M
 23000  -17.0   1.4   270   26   13   8.6   4.7   36.9  98.5     3.3      M    M
 22000  -14.5   5.9   270   23   12   8.6   4.7   36.6  97.9     3.0      M    M
 21000  -11.9  10.6   280   23   12   8.3   4.6   36.1  96.9     2.6      M    M
 20000   -9.4  15.1   290   23   12   8.3   4.6   35.5  96.0     2.2      M    M
 19500   -8.2  17.2   290   24   12   8.3   4.6   35.3  95.6     2.0      M    M
 19000   -6.9  19.6   295   24   12   7.8   4.3   35.1  95.2     1.9      M    M
 18500   -5.8  21.6   300   26   13   7.7   4.2   34.7  94.5     1.5      M    M
 18000   -4.1  24.6   300   29   15   7.6   4.1   34.2  93.6     1.1      M    M
 17500   -3.0  26.6   300   31   16   7.5   4.1   33.8  92.9     0.7      M    M
 17000   -1.8  28.8   300   33   17   7.4   4.0   33.4  92.2     0.4      M    M
 16500   -0.8  30.6   300   35   18   6.5   3.6   32.9  91.3    -0.1    894  4.5
 16000    0.1  32.2   300   38   19   6.6   3.6   32.4  90.3    -0.6    851  4.3
 15500    1.0  33.8   300   40   20   6.2   3.4   31.8  89.3    -1.1    808  4.1
 15000    1.9  35.4   300   41   21   6.3   3.4   31.2  88.2    -1.8    767  3.9
 14500    2.8  37.0   295   43   22   6.2   3.4   30.7  87.2    -2.4    727  3.7
 14000    3.6  38.5   295   43   22   6.3   3.4   30.1  86.1    -3.0    687  3.5
 13500    4.4  39.9   295   43   22   6.4   3.5   29.5  85.1    -3.7    647  3.3
 13000    5.3  41.5   295   42   22   6.5   3.6   29.0  84.1    -4.3    606  3.1
 12500    6.2  43.2   295   41   21   6.7   3.7   28.5  83.2    -4.9    565  2.9
 12000    7.1  44.8   295   39   20   7.2   3.9   28.0  82.4    -5.4    521  2.6
 11500    8.1  46.6   295   36   19   7.1   3.9   27.6  81.7    -5.9    476  2.4
 11000    9.1  48.4   295   33   17   6.5   3.6   27.1  80.8    -6.4    432  2.2
 10500   10.1  50.2   295   29   15   3.7   2.0   26.7  80.0    -7.0    388  2.0
 10250   10.3  50.5   295   28   14   4.0   2.2   26.1  78.9    -7.5    376  1.9
 10000   10.8  51.4   290   25   13   9.1   5.0   25.9  78.6    -7.7    352  1.8
  9750   11.5  52.7   290   23   12   8.7   4.8   25.8  78.5    -7.8    325  1.7
  9500   12.1  53.8   290   21   11   8.5   4.7   25.7  78.3    -7.9    299  1.5
  9250   12.7  54.9   290   19   10   7.5   4.1   25.6  78.1    -8.1    274  1.4
  9000   13.2  55.8   285   17    9   8.0   4.4   25.4  77.8    -8.3    250  1.3
  8750   13.9  57.0   285   16    8   8.7   4.8   25.3  77.6    -8.4    223  1.1
  8500   14.5  58.1   280   14    7   8.6   4.7   25.2  77.4    -8.5    197  1.0
  8250   15.2  59.4   280   12    6   8.7   4.8   25.2  77.3    -8.6    170  0.9
  8000   15.8  60.4   275   11    6   9.0   4.9   25.1  77.2    -8.7    143  0.7
  7750   16.5  61.7   275    9    5   9.3   5.1   25.1  77.1    -8.8    115  0.6
  7500   17.2  63.0   275    8    4   9.7   5.3   25.0  77.1    -8.8     87  0.4
  7250   17.9  64.2   275    7    4  10.1   5.5   25.0  77.1    -8.9     57  0.3
  7000   18.7  65.7   270    7    3  10.1   5.5   25.1  77.1    -8.9     27  0.1
  6750   19.4  66.9   270    6    3   9.1   5.0   25.1  77.1    -8.9      M    M
  6500   19.9  67.8   265    6    3   5.2   2.8   24.9  76.8    -9.1      M    M
  6250   20.1  68.2   255    6    3   1.8   1.0   24.4  75.9    -9.7      M    M
  6000   20.2  68.4   245    6    3   6.5   3.6   23.9  75.0   -10.3      M    M
  5750   20.6  69.1   235    7    3  -0.1  -0.0   23.6  74.5   -10.7      M    M
  5500   19.4  66.9   225    6    3 -26.9 -14.7   21.9  71.5   -12.6      M    M

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

           08/04/2015 at 0900 MDT          |       08/04/2015 at 1200 MDT
                                           |
K index... +8.1  LI... +0.9                | K index... +7.7  LI... -0.3
CAPE... +94.3  CIN... -241.9               | CAPE... +200.0  CIN... -139.7
                                           |
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 -62.3 -80.1  265  19 10   3.1   1.7 | -61.2 -78.2  260  22 11   3.2   1.7
 45000 -57.3 -71.1  275  29 15   3.9   2.1 | -56.6 -69.9  265  33 17   2.8   1.5
 40000 -51.3 -60.3  285  37 19   4.6   2.5 | -51.8 -61.2  290  42 22   4.9   2.7
 38000 -48.6 -55.5  290  36 18   4.6   2.5 | -48.9 -56.0  290  43 22   4.9   2.7
 36000 -45.5 -49.9  290  34 18   4.2   2.3 | -45.9 -50.6  295  44 23   4.7   2.6
 34000 -41.2 -42.2  290  35 18   7.5   4.1 | -41.6 -42.9  295  43 22   7.6   4.2
 32000 -36.7 -34.1  290  36 18   7.4   4.0 | -37.1 -34.8  290  41 21   7.6   4.1
 30000 -32.2 -26.0  285  35 18   7.5   4.1 | -32.4 -26.3  290  37 19   7.9   4.3
 29000 -30.0 -22.0  285  35 18   7.5   4.1 | -29.5 -21.1  290  34 18   7.9   4.3
 28000 -27.7 -17.9  285  35 18   7.0   3.8 | -27.2 -17.0  290  32 16   7.5   4.1
 27000 -25.8 -14.4  280  32 16   6.4   3.5 | -25.0 -13.0  285  30 15   7.5   4.1
 26000 -23.9 -11.0  275  29 15   6.4   3.5 | -22.7  -8.9  280  28 14   7.5   4.1
 25000 -22.0  -7.6  275  26 14   6.2   3.4 | -20.5  -4.9  275  26 14   7.5   4.1
 24000 -19.5  -3.1  275  25 13   8.7   4.8 | -18.4  -1.1  270  24 12   7.2   3.9
 23000 -17.0   1.4  275  24 12   8.7   4.7 | -16.3   2.7  265  22 11   7.2   3.9
 22000 -14.4   6.1  275  23 12   8.7   4.7 | -14.2   6.4  260  20 10   7.5   4.1
 21000 -11.8  10.8  280  23 12   8.6   4.7 | -11.8  10.8  270  19 10   8.3   4.5
 20000  -9.2  15.4  285  24 12   8.6   4.7 |  -9.3  15.3  280  19 10   8.2   4.5
 19500  -7.9  17.8  290  24 13   8.6   4.7 |  -8.0  17.6  285  20 10   8.1   4.5
 19000  -6.7  19.9  290  25 13   8.1   4.5 |  -6.7  19.9  290  21 11   9.4   5.2
 18500  -5.4  22.3  295  26 13   8.0   4.4 |  -5.3  22.5  295  24 12   9.3   5.1
 18000  -3.6  25.5  295  28 15   7.6   4.2 |  -3.8  25.2  300  27 14   8.8   4.8
 17500  -2.5  27.5  300  30 16   7.5   4.1 |  -2.6  27.3  300  30 15   7.9   4.3
 17000  -1.4  29.5  300  32 17   7.5   4.1 |  -1.4  29.5  305  33 17   8.1   4.4
 16500  -0.3  31.5  300  35 18   7.4   4.0 |  -0.4  31.3  305  35 18   5.7   3.1
 16000   0.8  33.4  300  37 19   7.5   4.1 |   0.5  32.9  305  38 19   5.8   3.2
 15500   1.8  35.2  300  39 20   5.9   3.2 |   1.4  34.5  305  40 21   5.9   3.2
 15000   2.7  36.9  300  40 21   5.9   3.2 |   2.7  36.9  300  42 22   6.0   3.3
 14500   3.6  38.5  300  42 22   5.7   3.1 |   3.6  38.5  300  43 22   5.8   3.2
 14000   4.3  39.7  300  43 22   5.6   3.1 |   4.4  39.9  295  44 23   5.9   3.3
 13500   5.1  41.2  300  44 22   5.6   3.1 |   5.2  41.4  295  45 23   5.9   3.2
 13000   5.9  42.6  300  43 22   5.6   3.1 |   5.9  42.6  295  43 22   6.0   3.3
 12500   6.6  43.9  295  43 22   6.0   3.3 |   6.7  44.1  290  41 21   6.6   3.6
 12000   7.5  45.5  295  41 21   6.9   3.8 |   7.6  45.7  290  37 19   7.3   4.0
 11500   8.4  47.1  295  39 20   7.1   3.9 |   8.6  47.5  290  33 17   7.5   4.1
 11000   9.3  48.7  295  36 18   7.1   3.9 |   9.7  49.5  290  29 15   7.9   4.3
 10500  10.3  50.5  295  32 16   4.5   2.5 |  10.9  51.6  290  25 13   4.7   2.6
 10250  10.5  50.9  295  31 16   3.7   2.0 |  11.1  52.0  290  24 12   5.2   2.9
 10000  11.0  51.8  295  29 15   7.7   4.2 |  11.7  53.1  290  21 11   9.9   5.4
  9750  11.5  52.7  295  26 13   7.8   4.3 |  12.3  54.1  285  18  9   8.9   4.9
  9500  12.0  53.6  295  23 12   7.3   4.0 |  13.0  55.4  285  15  8   8.2   4.5
  9250  12.5  54.5  295  20 11   5.8   3.2 |  13.5  56.3  280  13  7   7.0   3.8
  9000  12.9  55.2  295  18  9   6.5   3.5 |  14.1  57.4  275  11  6   9.2   5.0
  8750  13.4  56.1  290  15  8   7.3   4.0 |  14.8  58.6  270   9  5  10.4   5.7
  8500  13.9  57.0  285  13  7   7.4   4.1 |  15.5  59.9  265   8  4  10.0   5.5
  8250  14.5  58.1  285  10  5   8.0   4.4 |  16.3  61.3  260   7  4  10.1   5.6
  8000  15.1  59.2  275   8  4   8.3   4.6 |  17.0  62.6  260   7  4   9.7   5.3
  7750  15.8  60.4  270   6  3   8.6   4.7 |  17.7  63.9  260   7  4   9.2   5.0
  7500  16.4  61.5  255   5  3   9.2   5.0 |  18.4  65.1  260   7  4   9.8   5.4
  7250  17.1  62.8  250   5  2   9.7   5.3 |  19.2  66.6  260   7  3  10.3   5.7
  7000  17.9  64.2  245   4  2   9.3   5.1 |  19.9  67.8  255   7  3  10.1   5.5
  6750  18.5  65.3  240   4  2   8.8   4.8 |  20.7  69.3  255   6  3  10.3   5.7
  6500  19.2  66.6  240   4  2   9.1   5.0 |  21.4  70.5  255   6  3  10.7   5.9
  6250  19.9  67.8  235   3  2  10.2   5.6 |  22.3  72.1  255   6  3  11.6   6.4
  6000  20.5  68.9  230   3  2   8.2   4.5 |  23.1  73.6  255   6  3   8.9   4.9
  5750  21.1  70.0  225   3  2   9.6   5.3 |  23.8  74.8  255   6  3  13.3   7.3
  5500  22.0  71.6  220   3  2  18.0   9.9 |  25.3  77.5  255   6  3  29.4  16.1

           08/04/2015 at 1500 MDT          |       08/04/2015 at 1800 MDT
                                           |
K index... +19.1  LI... -0.6               | K index... +25.4  LI... -0.5
CAPE... +251.0  CIN... -25.8               | CAPE... +201.2  CIN... -22.6
                                           |
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  280  15  8   3.0   1.7 | -61.6 -78.9  295  19 10   2.7   1.5
 45000 -57.1 -70.8  285  26 13   2.7   1.5 | -57.4 -71.3  295  34 17   2.5   1.4
 40000 -52.4 -62.3  290  47 24   4.8   2.6 | -53.1 -63.6  295  46 24   5.7   3.1
 38000 -49.5 -57.1  290  48 25   4.8   2.7 | -49.7 -57.5  295  46 24   5.7   3.1
 36000 -46.6 -51.9  290  49 25   4.4   2.4 | -46.3 -51.3  295  46 24   5.4   3.0
 34000 -41.7 -43.1  290  45 23   8.8   4.8 | -41.3 -42.3  290  42 22   8.6   4.7
 32000 -36.4 -33.5  290  40 21   8.8   4.8 | -36.1 -33.0  285  37 19   8.6   4.7
 30000 -31.4 -24.5  295  37 19   8.1   4.4 | -30.3 -22.5  290  33 17   8.6   4.7
 29000 -28.4 -19.1  295  35 18   8.1   4.4 | -27.7 -17.9  295  32 16   8.6   4.7
 28000 -26.0 -14.8  300  34 18   7.5   4.1 | -25.2 -13.4  300  31 16   7.4   4.1
 27000 -23.8 -10.8  295  31 16   7.5   4.1 | -23.0  -9.4  300  33 17   7.5   4.1
 26000 -21.5  -6.7  295  29 15   7.5   4.1 | -20.8  -5.4  305  35 18   7.5   4.1
 25000 -19.3  -2.7  295  26 14   7.5   4.1 | -18.5  -1.3  310  36 19   7.2   3.9
 24000 -17.0   1.4  295  26 13   7.7   4.2 | -16.5   2.3  310  35 18   6.7   3.7
 23000 -14.7   5.5  295  26 13   7.7   4.2 | -14.5   5.9  310  34 18   6.7   3.7
 22000 -12.5   9.5  295  25 13   7.4   4.1 | -12.5   9.5  310  33 17   6.9   3.8
 21000 -10.4  13.3  295  28 14   6.9   3.8 | -10.4  13.3  310  32 17   7.1   3.9
 20000  -8.4  16.9  295  31 16   6.9   3.8 |  -8.2  17.2  310  32 16   7.1   3.9
 19500  -7.4  18.7  300  32 17   7.0   3.8 |  -7.2  19.0  310  32 16   7.2   4.0
 19000  -6.4  20.5  300  34 17   6.3   3.5 |  -6.2  20.8  305  32 16   6.0   3.3
 18500  -5.5  22.1  300  36 18   6.4   3.5 |  -5.3  22.5  305  33 17   6.1   3.4
 18000  -4.5  23.9  300  37 19   6.6   3.6 |  -4.4  24.1  300  34 17   6.1   3.4
 17500  -3.5  25.7  295  39 20   6.8   3.7 |  -3.6  25.5  295  35 18   6.1   3.4
 17000  -2.5  27.5  295  40 21   6.8   3.7 |  -2.7  27.1  290  36 19   6.2   3.4
 16500  -1.5  29.3  295  41 21   7.0   3.8 |  -1.7  28.9  290  37 19   8.7   4.8
 16000  -0.5  31.1  295  42 22   7.0   3.9 |  -0.6  30.9  285  36 19   8.7   4.7
 15500   1.1  34.0  290  42 22   7.6   4.2 |   1.3  34.3  285  36 18   9.4   5.2
 15000   2.1  35.8  290  41 21   7.7   4.2 |   2.6  36.7  285  35 18   9.4   5.2
 14500   3.2  37.8  290  40 20   8.2   4.5 |   4.0  39.2  285  34 18   9.2   5.1
 14000   4.3  39.7  285  37 19   8.4   4.6 |   5.3  41.5  285  33 17   9.2   5.1
 13500   5.4  41.7  285  35 18   8.8   4.9 |   6.6  43.9  285  31 16   8.9   4.9
 13000   6.7  44.1  285  32 17   9.0   5.0 |   7.9  46.2  285  28 15   8.8   4.9
 12500   8.0  46.4  285  30 16   8.9   4.9 |   9.1  48.4  285  26 13   9.1   5.0
 12000   9.3  48.7  285  28 14   8.6   4.7 |  10.5  50.9  285  24 12   9.3   5.1
 11500  10.6  51.1  285  25 13   8.6   4.7 |  11.9  53.4  290  22 11   9.4   5.1
 11000  11.8  53.2  285  22 11   8.5   4.6 |  13.3  55.9  290  20 11   9.2   5.0
 10500  13.1  55.6  285  18  9   5.3   2.9 |  14.7  58.5  295  19 10   5.2   2.9
 10250  13.4  56.1  285  18  9   7.1   3.9 |  15.0  59.0  295  19 10   6.6   3.6
 10000  14.2  57.6  285  16  8  12.5   6.9 |  15.9  60.6  295  18  9  12.9   7.1
  9750  15.1  59.2  285  15  8  11.5   6.3 |  16.7  62.1  295  18  9  11.7   6.4
  9500  15.9  60.6  285  13  7  10.1   5.6 |  17.6  63.7  295  17  9  10.3   5.6
  9250  16.6  61.9  285  12  6   8.6   4.7 |  18.3  64.9  300  17  9   8.7   4.8
  9000  17.3  63.1  285  12  6  10.3   5.7 |  19.0  66.2  300  17  8  10.3   5.6
  8750  18.1  64.6  285  12  6  11.0   6.1 |  19.8  67.6  300  16  8  10.7   5.9
  8500  18.9  66.0  285  11  6  10.5   5.8 |  20.5  68.9  300  16  8  10.4   5.7
  8250  19.6  67.3  285  11  6  10.1   5.5 |  21.3  70.3  300  16  8  10.4   5.7
  8000  20.4  68.7  285  11  6  10.0   5.5 |  22.1  71.8  300  16  8   9.9   5.4
  7750  21.1  70.0  285  11  5   9.7   5.3 |  22.8  73.0  300  15  8   9.3   5.1
  7500  21.8  71.2  285  10  5  10.2   5.6 |  23.5  74.3  300  15  8   9.8   5.4
  7250  22.6  72.7  285  10  5  10.7   5.9 |  24.2  75.6  305  15  8  10.1   5.5
  7000  23.4  74.1  285  10  5  10.1   5.6 |  25.0  77.0  305  15  8   9.9   5.4
  6750  24.1  75.4  285  10  5   9.5   5.2 |  25.7  78.3  305  15  8   9.7   5.3
  6500  24.9  76.8  290  10  5  10.2   5.6 |  26.5  79.7  305  14  7  10.2   5.6
  6250  25.7  78.3  290   9  5  11.5   6.3 |  27.2  81.0  305  14  7  10.7   5.9
  6000  26.5  79.7  290   9  5   9.5   5.2 |  28.0  82.4  305  14  7  10.0   5.5
  5750  27.2  81.0  290   9  5  13.5   7.4 |  28.8  83.8  305  13  7  11.5   6.3
  5500  28.7  83.7  290   8  4  27.4  15.0 |  29.8  85.6  305  12  6  16.8   9.2
________________________________________________________________________________

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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