Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220205
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
2004 MDT Friday, August 21, 2015

This forecast is for Saturday, August 22, 2015:

If the trigger temperature of 86.9 F/30.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 718 ft/min (3.6 m/s)
   Maximum height of thermals.................. 13140 ft MSL (7833 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1200 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................. 6332 ft MSL (1025 ft AGL)
Thermal soaring outlook for Sunday 08/23....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 19554 ft MSL (14247 ft AGL)
Wave soaring outlook for Sunday 08/23.......... Poor

Remarks...

Sunrise/Sunset.................... 06:17:55 / 19:47:25 MDT
Total possible sunshine........... 13 hr 29 min 31 sec (809 min 31 sec)
Altitude of sun at 13:02:17 MDT... 61.91 degrees

Upper air data from numerical model forecast valid on 08/22/2015 at 0600 MDT

Freezing level.................. 15993 ft MSL (10686 ft AGL)
Convective condensation level... 17687 ft MSL (12380 ft AGL)
Lifted condensation level....... 17219 ft MSL (11913 ft AGL)
Lifted index.................... -2.6
K index......................... +23.1

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  -61.6 -78.9   280   41   21   2.4   1.3      M     M       M      M    M
 45000  -58.2 -72.8   290   59   30   1.9   1.0      M     M       M      M    M
 40000  -54.8 -66.6   300   57   29   6.1   3.4      M     M       M      M    M
 38000  -51.3 -60.3   300   54   28   5.8   3.2      M     M       M      M    M
 36000  -47.9 -54.2   300   50   26   5.9   3.2      M     M       M      M    M
 34000  -43.4 -46.1   300   47   24   8.0   4.4      M     M       M      M    M
 32000  -38.6 -37.5   300   43   22   8.0   4.4      M     M       M      M    M
 30000  -33.9 -29.0   295   39   20   7.6   4.2   41.5 106.7     7.9      M    M
 29000  -31.1 -24.0   295   36   19   7.7   4.2   40.5 104.9     7.2      M    M
 28000  -28.8 -19.8   290   34   18   7.5   4.1   39.9 103.7     6.8      M    M
 27000  -26.6 -15.9   290   30   16   7.4   4.1   38.8 101.9     6.1      M    M
 26000  -24.4 -11.9   285   26   14   7.4   4.1   38.0 100.3     5.4      M    M
 25000  -22.2  -8.0   280   23   12   7.4   4.1   37.2  98.9     4.9      M    M
 24000  -20.0  -4.0   280   21   11   7.3   4.0   36.2  97.2     4.1      M    M
 23000  -17.8  -0.0   285   20   10   7.4   4.0   35.3  95.6     3.4      M    M
 22000  -15.7   3.7   290   19   10   7.5   4.1   34.6  94.2     2.7      M    M
 21000  -13.2   8.2   290   19   10   8.4   4.6   34.0  93.2     2.2      M    M
 20000  -10.7  12.7   290   21   11   8.5   4.6   33.5  92.4     1.8      M    M
 19500   -9.5  14.9   290   21   11   8.4   4.6   33.3  92.0     1.7      M    M
 19000   -8.2  17.2   285   22   11   9.0   4.9   33.2  91.7     1.5      M    M
 18500   -6.9  19.6   285   22   11   9.0   5.0   33.0  91.5     1.4      M    M
 18000   -5.6  21.9   285   22   11   9.0   5.0   32.9  91.3     1.2      M    M
 17500   -4.3  24.3   280   22   11   9.0   5.0   32.8  91.1     1.1      M    M
 17000   -2.9  26.8   280   22   11   9.1   5.0   32.7  90.8     0.9      M    M
 16500   -1.6  29.1   280   22   12   9.0   4.9   32.6  90.6     0.8      M    M
 16000   -0.3  31.5   280   22   12   9.0   4.9   32.4  90.4     0.7      M    M
 15500    1.6  34.9   280   22   11   9.1   5.0   32.3  90.1     0.4      M    M
 15000    3.0  37.4   280   22   11   9.1   5.0   32.1  89.9     0.3      M    M
 14500    4.3  39.7   280   21   11   9.2   5.0   32.0  89.7     0.2      M    M
 14000    5.7  42.3   280   19   10   9.2   5.1   32.0  89.5     0.1      M    M
 13500    7.1  44.8   280   17    9   9.3   5.1   31.9  89.4     0.0      M    M
 13000    8.5  47.3   275   17    9   9.5   5.2   31.8  89.3    -0.0    693  3.5
 12500    9.9  49.8   275   17    9   9.5   5.2   31.8  89.2    -0.1    636  3.2
 12000   11.3  52.3   275   17    9   9.6   5.3   31.8  89.2    -0.1    579  2.9
 11500   12.7  54.9   275   16    8   9.5   5.2   31.7  89.1    -0.2    522  2.6
 11000   14.0  57.2   275   17    9   8.6   4.7   31.6  88.9    -0.3    467  2.4
 10500   15.3  59.5   275   17    9  10.8   5.9   31.4  88.5    -0.5    415  2.1
 10250   16.2  61.2   280   18    9  11.2   6.2   31.6  88.9    -0.3    380  1.9
 10000   16.8  62.2   280   19   10   8.6   4.7   31.5  88.8    -0.4    353  1.8
  9750   17.5  63.5   280   19   10   9.4   5.1   31.5  88.7    -0.4    325  1.7
  9500   18.2  64.8   280   20   10   8.9   4.9   31.5  88.6    -0.5    298  1.5
  9250   18.8  65.8   280   20   10   8.0   4.4   31.4  88.4    -0.6    272  1.4
  9000   19.4  66.9   280   21   11   8.7   4.8   31.2  88.2    -0.7    247  1.3
  8750   20.1  68.2   280   21   11   9.6   5.3   31.2  88.1    -0.8    219  1.1
  8500   20.8  69.4   275   22   11   9.3   5.1   31.2  88.1    -0.8    191  1.0
  8250   21.4  70.5   275   23   12   9.3   5.1   31.1  88.0    -0.9    164  0.8
  8000   22.1  71.8   275   23   12   8.3   4.5   31.1  87.9    -1.0    137  0.7
  7750   22.6  72.7   275   23   12   7.5   4.1   30.9  87.6    -1.1    113  0.6
  7500   23.2  73.8   275   23   12   7.9   4.4   30.8  87.4    -1.3     89  0.4
  7250   23.8  74.8   270   22   11   9.1   5.0   30.7  87.2    -1.4     63  0.3
  7000   24.5  76.1   270   21   11   8.3   4.6   30.6  87.1    -1.5     35  0.2
  6750   25.1  77.2   270   20   10   9.8   5.4   30.5  86.9    -1.6      9  0.0
  6500   25.7  78.3   270   19   10  -0.5  -0.3   30.3  86.6    -1.8      M    M
  6250   24.9  76.8   265   17    9 -14.1  -7.7   28.9  83.9    -3.3      0  0.0
  6000   23.8  74.8   260   16    8 -13.2  -7.2   27.1  80.7    -5.1     25  0.1
  5750   22.6  72.7   250   15    8 -23.4 -12.9   25.1  77.2    -7.1     56  0.3
  5500   19.9  67.8   235   14    7 -45.0 -24.7   21.8  71.3   -10.5    129  0.7

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

           08/22/2015 at 0900 MDT          |       08/22/2015 at 1200 MDT
                                           |
K index... +24.0  LI... -0.9               | K index... +24.2  LI... -2.0
CAPE... +389.6  CIN... -63.0               | CAPE... +592.5  CIN... -38.0
                                           |
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 -61.9 -79.4  285  44 22   2.4   1.3 | -62.0 -79.6  290  41 21   2.0   1.1
 45000 -58.6 -73.5  290  62 32   1.6   0.9 | -58.9 -74.0  295  58 30   1.8   1.0
 40000 -55.5 -67.9  300  55 28   6.9   3.8 | -55.7 -68.3  295  54 28   7.3   4.0
 38000 -51.5 -60.7  300  53 27   6.6   3.6 | -51.4 -60.5  295  52 27   7.1   3.9
 36000 -47.6 -53.7  295  52 27   6.6   3.6 | -47.2 -53.0  300  49 25   7.0   3.9
 34000 -43.1 -45.6  295  49 25   7.7   4.2 | -42.7 -44.9  300  47 24   7.5   4.1
 32000 -38.5 -37.3  295  46 24   7.7   4.2 | -38.2 -36.8  295  44 23   7.6   4.2
 30000 -33.8 -28.8  295  41 21   7.9   4.4 | -32.9 -27.2  295  41 21   8.0   4.4
 29000 -30.8 -23.4  295  37 19   7.9   4.4 | -30.5 -22.9  295  39 20   8.0   4.4
 28000 -28.5 -19.3  290  34 17   7.1   3.9 | -28.1 -18.6  295  37 19   7.6   4.2
 27000 -26.5 -15.7  290  30 15   6.6   3.6 | -25.9 -14.6  290  34 17   7.4   4.1
 26000 -24.6 -12.3  280  26 13   6.7   3.6 | -23.7 -10.7  280  31 16   7.5   4.1
 25000 -22.6  -8.7  275  22 12   6.7   3.7 | -21.5  -6.7  275  28 14   7.5   4.1
 24000 -20.3  -4.5  275  21 11   7.9   4.3 | -19.3  -2.7  270  26 14   7.5   4.1
 23000 -18.0  -0.4  280  20 10   7.9   4.3 | -17.1   1.2  270  25 13   7.6   4.1
 22000 -15.7   3.7  285  19 10   8.0   4.4 | -14.8   5.4  265  24 13   7.7   4.2
 21000 -13.2   8.2  280  19 10   8.4   4.6 | -12.5   9.5  265  25 13   8.0   4.4
 20000 -10.8  12.6  280  20 10   8.4   4.6 | -10.1  13.8  265  25 13   8.0   4.4
 19500  -9.6  14.7  275  20 10   8.4   4.6 |  -8.9  16.0  265  26 13   7.9   4.3
 19000  -8.3  17.1  275  20 10   9.1   5.0 |  -7.7  18.1  270  26 13   9.3   5.1
 18500  -7.0  19.4  270  20 10   9.1   5.0 |  -6.3  20.7  270  25 13   9.3   5.1
 18000  -5.6  21.9  270  19 10   9.2   5.1 |  -4.9  23.2  270  24 12   9.0   4.9
 17500  -4.2  24.4  270  19 10   9.5   5.2 |  -3.7  25.3  270  25 13   8.2   4.5
 17000  -2.8  27.0  275  20 10   9.5   5.2 |  -2.5  27.5  270  25 13   8.2   4.5
 16500  -1.4  29.5  275  21 11   9.1   5.0 |  -1.2  29.8  270  25 13   9.2   5.0
 16000  -0.1  31.8  280  23 12   9.1   5.0 |   0.8  33.4  270  26 13   9.2   5.0
 15500   1.9  35.4  280  25 13   9.1   5.0 |   2.1  35.8  275  26 13   9.0   4.9
 15000   3.3  37.9  280  25 13   9.1   5.0 |   3.5  38.3  275  27 14   9.1   5.0
 14500   4.6  40.3  280  25 13   9.1   5.0 |   4.8  40.6  275  28 14   8.3   4.5
 14000   5.9  42.6  280  25 13   9.1   5.0 |   5.9  42.6  280  28 15   8.2   4.5
 13500   7.2  45.0  280  26 13   9.1   5.0 |   7.1  44.8  280  29 15   8.2   4.5
 13000   8.6  47.5  280  25 13   9.2   5.1 |   8.3  46.9  280  28 14   8.2   4.5
 12500   9.9  49.8  280  25 13   9.2   5.0 |   9.5  49.1  280  26 14   8.4   4.6
 12000  11.2  52.2  280  24 13   9.0   4.9 |  10.7  51.3  280  26 13   8.7   4.8
 11500  12.6  54.7  280  23 12   8.8   4.9 |  11.9  53.4  280  25 13   8.5   4.7
 11000  13.7  56.7  285  23 12   7.8   4.3 |  13.1  55.6  280  23 12   7.7   4.2
 10500  14.8  58.6  285  22 11  11.8   6.4 |  14.2  57.6  280  21 11  10.9   6.0
 10250  15.9  60.6  285  21 11  12.6   6.9 |  15.1  59.2  280  19 10  12.1   6.6
 10000  16.5  61.7  285  21 11   7.9   4.4 |  15.8  60.4  285  17  9   8.6   4.7
  9750  17.2  63.0  285  21 11   9.3   5.1 |  16.5  61.7  285  15  8   9.7   5.3
  9500  17.8  64.0  290  20 10   8.6   4.7 |  17.2  63.0  290  14  7   8.8   4.8
  9250  18.4  65.1  290  20 10   8.0   4.4 |  17.8  64.0  290  13  7   8.7   4.8
  9000  19.0  66.2  290  20 10   8.3   4.6 |  18.5  65.3  295  12  6   9.9   5.4
  8750  19.6  67.3  290  20 10   8.8   4.8 |  19.2  66.6  295  12  6  10.3   5.6
  8500  20.3  68.5  290  20 10   8.6   4.7 |  20.0  68.0  295  12  6  10.2   5.6
  8250  20.9  69.6  290  21 11   8.9   4.9 |  20.8  69.4  295  11  6  10.5   5.8
  8000  21.6  70.9  290  22 11   8.2   4.5 |  21.5  70.7  295  11  6  10.1   5.5
  7750  22.1  71.8  290  23 12   7.6   4.1 |  22.3  72.1  300  11  6   9.5   5.2
  7500  22.7  72.9  290  24 13   7.4   4.0 |  23.0  73.4  300  11  6   9.8   5.4
  7250  23.2  73.8  290  24 12   7.0   3.8 |  23.7  74.7  300  11  6  10.0   5.5
  7000  23.7  74.7  285  24 12   6.1   3.3 |  24.5  76.1  300  11  5   9.9   5.5
  6750  24.1  75.4  285  23 12   6.0   3.3 |  25.2  77.4  300  10  5   9.4   5.2
  6500  24.5  76.1  280  21 11   0.5   0.3 |  25.9  78.6  300  10  5  10.2   5.6
  6250  24.2  75.6  280  18  9  -4.2  -2.3 |  26.7  80.1  305  10  5  11.4   6.3
  6000  23.9  75.0  275  15  8  -3.7  -2.1 |  27.6  81.7  305  10  5  10.3   5.7
  5750  23.5  74.3  270  11  6  -6.7  -3.7 |  28.4  83.1  305  10  5  12.1   6.6
  5500  23.0  73.4  250   8  4  -1.9  -1.1 |  29.5  85.1  305   9  5  20.5  11.2

           08/22/2015 at 1500 MDT          |       08/22/2015 at 1800 MDT
                                           |
K index... +31.1  LI... -2.9               | K index... +26.8  LI... -1.8
CAPE... +632.8  CIN... -25.2               | CAPE... +235.7  CIN... -186.6
                                           |
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 -61.9 -79.4  285  42 22   1.6   0.9 | -63.8 -82.8  285  43 22   1.8   1.0
 45000 -59.2 -74.6  295  59 31   1.9   1.0 | -60.2 -76.4  295  51 26   3.5   1.9
 40000 -55.8 -68.4  295  54 28   7.1   3.9 | -54.5 -66.1  290  42 22   6.7   3.7
 38000 -51.6 -60.9  295  52 27   7.0   3.8 | -50.5 -58.9  290  42 21   6.8   3.7
 36000 -47.4 -53.3  295  49 25   6.9   3.8 | -46.4 -51.5  290  41 21   6.6   3.6
 34000 -42.6 -44.7  295  45 23   8.3   4.5 | -41.5 -42.7  290  38 20   8.5   4.6
 32000 -37.6 -35.7  295  41 21   8.3   4.5 | -35.8 -32.4  290  35 18   8.6   4.7
 30000 -32.4 -26.3  300  38 19   7.6   4.2 | -30.8 -23.4  295  34 17   8.2   4.5
 29000 -30.1 -22.2  300  37 19   7.6   4.2 | -28.4 -19.1  300  33 17   8.2   4.5
 28000 -27.8 -18.0  300  35 18   8.3   4.5 | -26.0 -14.8  300  32 17   7.5   4.1
 27000 -25.3 -13.5  295  34 17   8.5   4.6 | -23.7 -10.7  295  30 16   7.4   4.1
 26000 -22.8  -9.0  290  32 16   8.5   4.7 | -21.5  -6.7  290  29 15   7.4   4.1
 25000 -20.2  -4.4  285  31 16   8.2   4.5 | -19.3  -2.7  280  28 14   7.6   4.2
 24000 -18.3  -0.9  285  32 16   6.3   3.5 | -16.8   1.8  285  30 15   8.3   4.6
 23000 -16.4   2.5  285  34 17   6.4   3.5 | -14.4   6.1  285  32 16   8.3   4.6
 22000 -14.5   5.9  280  35 18   6.5   3.6 | -11.9  10.6  290  34 18   7.3   4.0
 21000 -12.5   9.5  280  36 18   7.0   3.9 | -10.4  13.3  285  35 18   4.7   2.6
 20000 -10.5  13.1  275  36 19   7.2   3.9 |  -9.1  15.6  285  37 19   4.9   2.7
 19500  -9.5  14.9  270  37 19   7.1   3.9 |  -8.4  16.9  280  37 19   4.8   2.6
 19000  -8.4  16.9  270  36 19   9.3   5.1 |  -7.5  18.5  280  38 19   8.2   4.5
 18500  -7.0  19.4  270  35 18   9.3   5.1 |  -6.4  20.5  280  37 19   8.2   4.5
 18000  -5.7  21.7  270  33 17   9.3   5.1 |  -5.2  22.6  280  37 19   8.3   4.6
 17500  -4.4  24.1  270  31 16   9.4   5.2 |  -4.0  24.8  280  36 18   8.6   4.7
 17000  -3.0  26.6  265  29 15   9.5   5.2 |  -2.8  27.0  280  34 18   8.6   4.7
 16500  -1.7  28.9  265  27 14   8.8   4.8 |  -0.9  30.4  280  32 16   9.0   5.0
 16000   0.2  32.4  265  24 12   8.9   4.9 |   0.4  32.7  280  30 15   9.1   5.0
 15500   1.5  34.7  265  21 11   8.6   4.7 |   1.7  35.1  280  28 14   8.6   4.7
 15000   2.7  36.9  265  19 10   8.6   4.7 |   2.9  37.2  280  26 13   8.7   4.8
 14500   4.0  39.2  260  16  8   8.7   4.8 |   4.2  39.6  280  24 12   8.1   4.4
 14000   5.3  41.5  265  14  7   8.7   4.8 |   5.3  41.5  275  21 11   8.0   4.4
 13500   6.6  43.9  265  11  6   8.6   4.7 |   6.5  43.7  275  19 10   7.5   4.1
 13000   7.9  46.2  275   8  4   8.6   4.7 |   7.5  45.5  275  17  9   7.2   3.9
 12500   9.1  48.4  290   6  3   9.0   4.9 |   8.6  47.5  275  14  7   7.4   4.0
 12000  10.6  51.1  315   5  3   9.7   5.3 |   9.7  49.5  280  12  6   7.8   4.3
 11500  12.0  53.6  335   6  3   9.7   5.3 |  10.8  51.4  285  10  5   7.6   4.2
 11000  13.5  56.3  340   6  3   9.5   5.2 |  11.9  53.4  295   7  4   6.7   3.7
 10500  14.9  58.8  345   6  3   6.0   3.3 |  12.9  55.2  320   5  3   4.0   2.2
 10250  15.2  59.4  345   6  3   7.1   3.9 |  13.0  55.4  325   5  2   3.5   1.9
 10000  16.1  61.0  350   6  3  12.6   6.9 |  13.4  56.1  360   4  2   6.7   3.7
  9750  17.0  62.6  350   6  3  11.5   6.3 |  13.9  57.0  035   4  2   6.2   3.4
  9500  17.8  64.0  350   7  3  10.3   5.7 |  14.3  57.7  055   6  3   5.2   2.8
  9250  18.5  65.3  350   7  3   8.7   4.7 |  14.5  58.1  065   9  4   2.1   1.1
  9000  19.2  66.6  350   7  3  10.0   5.5 |  14.6  58.3  070  12  6   1.3   0.7
  8750  19.9  67.8  350   7  4  10.4   5.7 |  14.6  58.3  075  15  8   0.7   0.4
  8500  20.7  69.3  355   7  4  10.4   5.7 |  14.7  58.5  075  19 10   3.6   2.0
  8250  21.5  70.7  355   7  4  10.9   6.0 |  15.1  59.2  075  20 11   7.8   4.3
  8000  22.3  72.1  355   7  4  10.0   5.5 |  15.7  60.3  075  22 11   8.9   4.9
  7750  23.0  73.4  355   7  4   8.9   4.9 |  16.4  61.5  075  22 11   9.9   5.4
  7500  23.7  74.7  355   7  4   9.8   5.4 |  17.2  63.0  075  22 11  10.2   5.6
  7250  24.5  76.1  355   7  4  10.6   5.8 |  18.0  64.4  070  22 11  10.7   5.9
  7000  25.2  77.4  355   7  4  10.3   5.7 |  18.7  65.7  070  22 11  10.2   5.6
  6750  26.0  78.8  355   8  4   9.9   5.4 |  19.4  66.9  070  22 11   9.2   5.1
  6500  26.7  80.1  355   8  4  10.2   5.6 |  20.1  68.2  070  22 11  10.0   5.5
  6250  27.5  81.5  355   8  4  10.9   6.0 |  21.0  69.8  070  21 11  11.3   6.2
  6000  28.3  82.9  355   8  4   9.9   5.4 |  21.8  71.2  070  21 11   9.9   5.4
  5750  29.1  84.4  360   8  4  12.9   7.1 |  22.5  72.5  070  20 11  12.9   7.1
  5500  30.4  86.7  360   8  4  23.3  12.8 |  23.8  74.8  070  19 10  21.5  11.8
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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