Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 020103
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1903 MDT Tuesday, September 1, 2015

This forecast is for Wednesday, September 2, 2015:

If the trigger temperature of 80.6 F/27.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1114 ft/min (5.7 m/s)
   Maximum height of thermals.................. 17650 ft MSL (12343 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1045 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................. 14657 ft MSL (9351 ft AGL)
Thermal soaring outlook for Thursday 09/03..... 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....................... 40937 ft MSL (35630 ft AGL)
Wave soaring outlook for Thursday 09/03........ Poor

Remarks... None

Sunrise/Sunset.................... 06:28:13 / 19:30:52 MDT
Total possible sunshine........... 13 hr 2 min 38 sec (782 min 38 sec)
Altitude of sun at 12:59:05 MDT... 58.05 degrees

Upper air data from numerical model forecast valid on 09/02/2015 at 0600 MDT

Freezing level.................. 15383 ft MSL (10076 ft AGL)
Convective condensation level... 16753 ft MSL (11446 ft AGL)
Lifted condensation level....... 17314 ft MSL (12007 ft AGL)
Lifted index.................... -1.2
K index......................... +19.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -64.4 -83.9   260   40   20   1.0   0.5      M     M       M      M    M
 45000  -61.9 -79.4   260   57   30   3.8   2.1      M     M       M      M    M
 40000  -55.1 -67.2   260   65   33   8.2   4.5      M     M       M      M    M
 38000  -50.1 -58.2   260   58   30   8.3   4.6      M     M       M      M    M
 36000  -45.1 -49.2   260   52   27   8.3   4.6      M     M       M      M    M
 34000  -40.1 -40.2   265   49   25   8.3   4.6      M     M       M      M    M
 32000  -35.1 -31.2   265   46   24   8.3   4.5      M     M       M      M    M
 30000  -29.7 -21.5   265   42   21   8.0   4.4   46.0 114.8    10.1      M    M
 29000  -27.3 -17.1   265   40   21   8.1   4.4   45.4 113.8     9.7      M    M
 28000  -24.9 -12.8   265   38   20   7.0   3.8   44.8 112.7     9.4      M    M
 27000  -22.9  -9.2   265   35   18   6.8   3.7   43.6 110.4     8.5      M    M
 26000  -20.9  -5.6   265   31   16   6.8   3.7   42.4 108.4     7.7      M    M
 25000  -18.9  -2.0   260   28   14   6.8   3.7   41.5 106.6     6.9      M    M
 24000  -16.8   1.8   260   26   14   6.9   3.8   40.3 104.5     6.0      M    M
 23000  -14.8   5.4   260   25   13   6.9   3.8   39.2 102.6     5.2      M    M
 22000  -12.8   9.0   260   23   12   6.8   3.7   38.3 100.9     4.4      M    M
 21000  -10.8  12.6   260   22   11   6.6   3.6   37.1  98.8     3.5      M    M
 20000   -8.9  16.0   260   20   10   6.6   3.6   36.0  96.8     2.5      M    M
 19500   -7.9  17.8   260   19   10   6.7   3.7   35.5  95.9     2.1      M    M
 19000   -6.9  19.6   260   18    9   6.2   3.4   35.0  94.9     1.6      M    M
 18500   -6.0  21.2   260   17    9   6.2   3.4   34.3  93.8     1.1      M    M
 18000   -5.2  22.6   260   16    8   6.3   3.4   33.7  92.7     0.5      M    M
 17500   -4.2  24.4   255   15    8   6.4   3.5   33.1  91.7    -0.1   1109  5.6
 17000   -3.3  26.1   255   14    7   6.4   3.5   32.6  90.6    -0.6   1067  5.4
 16500   -2.4  27.7   250   13    7   6.6   3.6   32.0  89.6    -1.2   1025  5.2
 16000   -1.5  29.3   245   13    6   6.6   3.6   31.5  88.7    -1.7    982  5.0
 15500    0.0  32.0   245   12    6   7.6   4.2   30.8  87.4    -2.4    916  4.7
 15000    1.1  34.0   245   12    6   7.5   4.1   30.4  86.7    -2.8    869  4.4
 14500    2.2  36.0   240   12    6   8.0   4.4   30.1  86.1    -3.2    821  4.2
 14000    3.4  38.1   245   12    6   8.2   4.5   29.8  85.6    -3.5    771  3.9
 13500    4.5  40.1   245   11    6   8.3   4.5   29.6  85.2    -3.8    720  3.7
 13000    5.8  42.4   250   11    6   8.3   4.6   29.3  84.8    -4.0    668  3.4
 12500    7.0  44.6   255   11    6   8.5   4.6   29.1  84.4    -4.2    616  3.1
 12000    8.3  46.9   260   11    6   8.8   4.8   28.9  84.1    -4.4    562  2.9
 11500    9.6  49.3   270   11    6   8.6   4.7   28.8  83.8    -4.6    508  2.6
 11000   10.9  51.6   275   12    6   8.1   4.4   28.6  83.4    -4.8    456  2.3
 10500   12.2  54.0   285   12    6   3.9   2.1   28.4  83.0    -5.0    403  2.0
 10250   12.3  54.1   285   13    7   5.5   3.0   27.7  81.9    -5.6    392  2.0
 10000   13.1  55.6   290   13    7  12.2   6.7   27.8  82.1    -5.6    360  1.8
  9750   13.9  57.0   290   14    7  10.8   5.9   27.9  82.2    -5.5    329  1.7
  9500   14.7  58.5   295   14    7   9.7   5.3   28.0  82.4    -5.4    297  1.5
  9250   15.3  59.5   295   15    7   7.4   4.1   27.9  82.2    -5.6    272  1.4
  9000   15.9  60.6   295   15    8   8.8   4.8   27.7  81.9    -5.7    248  1.3
  8750   16.6  61.9   295   15    8  10.0   5.5   27.7  81.9    -5.8    219  1.1
  8500   17.3  63.1   295   16    8   9.2   5.1   27.7  81.9    -5.8    191  1.0
  8250   17.9  64.2   295   16    8   8.5   4.6   27.6  81.8    -5.9    164  0.8
  8000   18.5  65.3   295   17    9   8.6   4.7   27.6  81.6    -6.0    138  0.7
  7750   19.2  66.6   300   17    9   9.1   5.0   27.5  81.5    -6.2    112  0.6
  7500   19.8  67.6   300   18    9   8.6   4.7   27.4  81.4    -6.3     85  0.4
  7250   20.4  68.7   300   18    9   8.0   4.4   27.3  81.1    -6.4     60  0.3
  7000   21.0  69.8   295   19   10   8.6   4.7   27.2  80.9    -6.6     35  0.2
  6750   21.6  70.9   295   19   10   7.3   4.0   27.1  80.7    -6.7     10  0.1
  6500   21.9  71.4   295   19   10   0.5   0.3   26.7  80.0    -7.2      M    M
  6250   21.6  70.9   295   17    9  -4.9  -2.7   25.7  78.3    -8.2      M    M
  6000   21.3  70.3   290   16    8   1.6   0.9   24.7  76.5    -9.2      M    M
  5750   21.4  70.5   285   14    7  -6.7  -3.7   24.1  75.4    -9.9      M    M
  5500   19.5  67.1   270    9    5 -41.0 -22.5   21.6  70.9   -12.6     36  0.2

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

           09/02/2015 at 0900 MDT          |       09/02/2015 at 1200 MDT
                                           |
K index... +17.0  LI... +0.5               | K index... +15.7  LI... -0.9
CAPE... 0.0  CIN... M                      | CAPE... +24.6  CIN... -42.2
                                           |
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 -64.5 -84.1  260  35 18   0.6   0.4 | -65.1 -85.2  255  36 18   0.7   0.4
 45000 -62.2 -80.0  260  57 29   4.0   2.2 | -62.4 -80.3  260  52 27   4.2   2.3
 40000 -55.1 -67.2  260  61 31   8.4   4.6 | -55.3 -67.5  260  51 26   8.6   4.7
 38000 -50.0 -58.0  260  55 28   8.5   4.7 | -50.1 -58.2  255  46 24   8.7   4.7
 36000 -44.9 -48.8  265  49 25   8.5   4.7 | -44.9 -48.8  250  42 22   8.7   4.8
 34000 -40.0 -40.0  265  45 23   8.1   4.5 | -40.0 -40.0  255  39 20   8.2   4.5
 32000 -35.2 -31.4  265  42 22   8.1   4.4 | -35.0 -31.0  260  36 18   8.2   4.5
 30000 -29.6 -21.3  265  38 20   8.3   4.5 | -29.7 -21.5  260  34 17   7.9   4.3
 29000 -27.2 -17.0  265  37 19   8.3   4.5 | -27.4 -17.3  260  33 17   7.9   4.3
 28000 -24.8 -12.6  265  35 18   7.2   4.0 | -25.0 -13.0  260  32 17   7.9   4.4
 27000 -22.6  -8.7  265  32 16   7.1   3.9 | -22.6  -8.7  260  30 16   8.0   4.4
 26000 -20.5  -4.9  265  29 15   7.1   3.9 | -20.2  -4.4  260  28 14   8.0   4.4
 25000 -18.4  -1.1  265  26 14   7.0   3.8 | -17.8  -0.0  260  26 13   7.6   4.2
 24000 -16.5   2.3  265  24 13   6.4   3.5 | -15.9   3.4  260  24 12   6.1   3.4
 23000 -14.6   5.7  265  22 12   6.4   3.5 | -14.1   6.6  260  22 11   6.1   3.4
 22000 -12.7   9.1  265  20 11   6.5   3.5 | -12.2  10.0  260  20 10   6.1   3.3
 21000 -10.7  12.7  265  20 10   6.7   3.7 | -10.5  13.1  260  19 10   6.0   3.3
 20000  -8.8  16.2  265  19 10   6.7   3.7 |  -8.7  16.3  265  18  9   6.1   3.3
 19500  -7.8  18.0  265  19 10   6.8   3.7 |  -7.9  17.8  270  18  9   6.0   3.3
 19000  -6.8  19.8  265  18  9   7.0   3.8 |  -6.9  19.6  270  17  9   7.2   3.9
 18500  -5.8  21.6  265  18  9   7.0   3.8 |  -5.9  21.4  270  17  9   7.2   3.9
 18000  -4.7  23.5  265  17  9   6.9   3.8 |  -4.8  23.4  270  17  9   7.1   3.9
 17500  -3.7  25.3  260  16  8   6.8   3.7 |  -3.7  25.3  275  17  9   7.0   3.9
 17000  -2.7  27.1  260  15  8   6.9   3.8 |  -2.7  27.1  275  17  9   7.1   3.9
 16500  -1.8  28.8  260  14  7   5.9   3.2 |  -1.7  28.9  275  17  9   6.3   3.5
 16000  -0.9  30.4  260  13  7   5.9   3.3 |  -0.4  31.3  275  17  9   6.4   3.5
 15500   0.4  32.7  260  12  6   6.3   3.5 |   0.6  33.1  275  16  8   6.4   3.5
 15000   1.3  34.3  260  11  6   6.2   3.4 |   1.5  34.7  280  16  8   6.4   3.5
 14500   2.2  36.0  260  10  5   7.2   4.0 |   2.4  36.3  280  15  8   7.3   4.0
 14000   3.3  37.9  260  10  5   7.4   4.1 |   3.5  38.3  280  14  7   7.5   4.1
 13500   4.4  39.9  265   9  5   7.8   4.3 |   4.6  40.3  285  13  7   7.9   4.3
 13000   5.5  41.9  270   9  4   8.0   4.4 |   5.7  42.3  285  12  6   8.1   4.5
 12500   6.7  44.1  280   8  4   8.1   4.4 |   6.9  44.4  290  10  5   8.4   4.6
 12000   7.8  46.0  295   7  4   8.2   4.5 |   8.2  46.8  300   9  5   8.7   4.8
 11500   9.0  48.2  310   7  4   8.2   4.5 |   9.5  49.1  310   8  4   8.7   4.8
 11000  10.2  50.4  325   8  4   8.2   4.5 |  10.8  51.4  315   9  5   8.6   4.7
 10500  11.4  52.5  330   9  5   4.5   2.5 |  12.1  53.8  320  10  5   5.1   2.8
 10250  11.6  52.9  330   9  5   6.3   3.4 |  12.3  54.1  320   9  5   6.1   3.3
 10000  12.5  54.5  330  11  5  12.4   6.8 |  13.0  55.4  320   9  5  11.4   6.2
  9750  13.3  55.9  330  12  6  11.2   6.1 |  13.8  56.8  325   9  5  10.5   5.8
  9500  14.1  57.4  330  13  7  10.0   5.5 |  14.5  58.1  325   9  5   9.1   5.0
  9250  14.7  58.5  330  13  7   7.8   4.3 |  15.0  59.0  325   9  4   7.3   4.0
  9000  15.3  59.5  330  14  7   9.5   5.2 |  15.5  59.9  325   8  4   9.7   5.3
  8750  16.1  61.0  330  15  8  10.9   6.0 |  16.3  61.3  325   8  4  10.8   5.9
  8500  16.8  62.2  330  16  8   9.7   5.3 |  17.0  62.6  320   7  4  10.4   5.7
  8250  17.5  63.5  325  17  9   8.6   4.7 |  17.8  64.0  320   7  4  10.6   5.8
  8000  18.1  64.6  320  17  9   8.7   4.8 |  18.6  65.5  320   7  4  10.0   5.5
  7750  18.7  65.7  320  18  9   8.7   4.8 |  19.3  66.7  320   7  3   9.2   5.0
  7500  19.3  66.7  315  19 10   8.4   4.6 |  20.0  68.0  320   7  3   9.9   5.4
  7250  19.9  67.8  315  19 10   8.0   4.4 |  20.7  69.3  320   7  3  10.6   5.8
  7000  20.5  68.9  310  19 10   8.4   4.6 |  21.5  70.7  320   7  3   9.8   5.4
  6750  21.1  70.0  305  19 10   6.8   3.8 |  22.2  72.0  320   7  3   9.3   5.1
  6500  21.4  70.5  305  18  9   1.9   1.0 |  23.0  73.4  320   6  3  10.6   5.8
  6250  21.4  70.5  300  15  8   1.0   0.6 |  23.8  74.8  320   6  3  12.1   6.7
  6000  21.5  70.7  290  13  6  -2.5  -1.4 |  24.7  76.5  320   6  3   9.8   5.4
  5750  21.1  70.0  280   9  5  -1.5  -0.8 |  25.4  77.7  320   6  3  13.7   7.5
  5500  21.5  70.7  265   7  4  15.1   8.3 |  26.9  80.4  320   6  3  26.6  14.6

           09/02/2015 at 1500 MDT          |       09/02/2015 at 1800 MDT
                                           |
K index... +17.0  LI... -0.5               | K index... +26.7  LI... -0.6
CAPE... +0.2  CIN... -7.0                  | CAPE... 0.0  CIN... -18.6
                                           |
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 -65.3 -85.5  250  36 19   0.9   0.5 | -65.9 -86.6  250  36 18   0.5   0.3
 45000 -62.2 -80.0  260  46 24   4.4   2.4 | -62.7 -80.9  250  45 23   5.4   3.0
 40000 -54.9 -66.8  265  46 24   8.7   4.7 | -54.0 -65.2  250  52 27   8.4   4.6
 38000 -49.6 -57.3  255  44 22   8.7   4.8 | -49.0 -56.2  250  47 24   8.4   4.6
 36000 -44.4 -47.9  250  42 21   8.7   4.8 | -44.0 -47.2  255  42 22   8.4   4.6
 34000 -39.4 -38.9  245  38 20   8.4   4.6 | -39.0 -38.2  255  42 22   8.4   4.6
 32000 -34.3 -29.7  240  34 18   8.3   4.5 | -33.9 -29.0  255  42 22   8.2   4.5
 30000 -29.3 -20.7  245  31 16   7.3   4.0 | -28.6 -19.5  255  36 19   7.9   4.3
 29000 -27.1 -16.8  250  31 16   7.3   4.0 | -26.2 -15.2  255  33 17   7.9   4.4
 28000 -24.8 -12.6  255  30 15   8.3   4.6 | -23.9 -11.0  255  30 15   6.7   3.7
 27000 -22.4  -8.3  255  28 15   8.3   4.6 | -22.0  -7.6  255  27 14   6.6   3.6
 26000 -19.9  -3.8  255  27 14   8.3   4.6 | -20.0  -4.0  250  25 13   6.6   3.6
 25000 -17.4   0.7  255  25 13   7.7   4.2 | -18.1  -0.6  250  22 12   6.7   3.7
 24000 -15.4   4.3  255  23 12   6.3   3.5 | -16.0   3.2  255  21 11   7.0   3.8
 23000 -13.4   7.9  255  21 11   6.4   3.5 | -13.9   7.0  260  20 10   7.0   3.8
 22000 -11.5  11.3  255  18  9   5.9   3.2 | -11.9  10.6  265  20 10   6.6   3.6
 21000 -10.0  14.0  260  19 10   4.9   2.7 | -10.2  13.6  265  19 10   5.7   3.1
 20000  -8.6  16.5  265  19 10   5.0   2.7 |  -8.6  16.5  270  19 10   5.7   3.1
 19500  -7.8  18.0  270  20 10   4.8   2.6 |  -7.8  18.0  270  19 10   5.7   3.1
 19000  -7.0  19.4  270  20 10   7.4   4.1 |  -7.0  19.4  270  18  9   6.3   3.5
 18500  -5.9  21.4  270  20 10   7.3   4.0 |  -6.1  21.0  270  16  8   6.4   3.5
 18000  -4.9  23.2  270  19 10   7.6   4.2 |  -5.2  22.6  270  13  7   6.6   3.6
 17500  -3.7  25.3  270  19 10   8.0   4.4 |  -4.2  24.4  275  13  6   7.1   3.9
 17000  -2.6  27.3  275  18  9   8.1   4.4 |  -3.1  26.4  275  12  6   6.9   3.8
 16500  -1.5  29.3  275  18  9   7.7   4.2 |  -2.0  28.4  280  11  6   8.8   4.8
 16000   0.2  32.4  275  17  9   7.8   4.3 |  -0.1  31.8  285  10  5   8.8   4.8
 15500   1.4  34.5  280  16  8   8.0   4.4 |   1.2  34.2  285   9  5   8.1   4.4
 15000   2.5  36.5  285  15  8   8.0   4.4 |   2.4  36.3  285   8  4   8.1   4.5
 14500   3.7  38.7  285  14  7   8.0   4.4 |   3.6  38.5  285   7  4   8.6   4.7
 14000   4.9  40.8  290  13  7   8.0   4.4 |   4.9  40.8  285   6  3   8.7   4.8
 13500   6.1  43.0  300  12  6   8.3   4.5 |   6.1  43.0  280   5  3   8.5   4.7
 13000   7.3  45.1  305  11  6   8.4   4.6 |   7.4  45.3  265   4  2   8.4   4.6
 12500   8.5  47.3  310  10  5   8.4   4.6 |   8.7  47.7  250   4  2   8.6   4.7
 12000   9.7  49.5  315   8  4   8.2   4.5 |  10.0  50.0  235   3  2   9.0   4.9
 11500  10.9  51.6  315   6  3   8.2   4.5 |  11.4  52.5  220   3  2   9.0   4.9
 11000  12.1  53.8  315   4  2   7.8   4.3 |  12.8  55.0  210   3  1   8.9   4.9
 10500  13.2  55.8  310   2  1   4.7   2.6 |  14.1  57.4  205   3  1   5.0   2.8
 10250  13.4  56.1  310   2  1   6.0   3.3 |  14.3  57.7  205   3  1   5.9   3.2
 10000  14.2  57.6  300   1  1  11.3   6.2 |  15.1  59.2  200   2  1  11.7   6.4
  9750  14.9  58.8  285   1  1  10.2   5.6 |  15.9  60.6  200   2  1  10.4   5.7
  9500  15.6  60.1  255   1  0   9.7   5.3 |  16.7  62.1  200   2  1   9.7   5.3
  9250  16.2  61.2  245   1  0   9.1   5.0 |  17.3  63.1  200   2  1   8.1   4.5
  9000  17.0  62.6  250   1  0  10.5   5.8 |  17.9  64.2  205   1  1   8.9   4.9
  8750  17.8  64.0  250   1  0  11.1   6.1 |  18.6  65.5  215   1  1   9.4   5.1
  8500  18.6  65.5  245   1  0  10.6   5.8 |  19.3  66.7  225   1  1   9.6   5.2
  8250  19.4  66.9  245   1  0  10.3   5.6 |  20.0  68.0  235   1  1  10.4   5.7
  8000  20.1  68.2  240   1  0  10.0   5.5 |  20.8  69.4  245   1  1  10.0   5.5
  7750  20.8  69.4  245   1  1   9.6   5.3 |  21.5  70.7  250   1  1   9.3   5.1
  7500  21.6  70.9  245   1  1   9.7   5.3 |  22.2  72.0  255   1  1   9.9   5.4
  7250  22.3  72.1  245   1  1   9.7   5.3 |  23.0  73.4  260   1  1  10.4   5.7
  7000  23.0  73.4  245   1  1   9.9   5.4 |  23.7  74.7  260   1  1  10.1   5.6
  6750  23.8  74.8  245   1  1  10.5   5.8 |  24.5  76.1  265   2  1   9.5   5.2
  6500  24.6  76.3  245   1  1  10.6   5.8 |  25.2  77.4  270   2  1  10.0   5.5
  6250  25.4  77.7  245   1  1  10.9   6.0 |  26.0  78.8  270   2  1  10.8   5.9
  6000  26.2  79.2  245   1  1   9.6   5.2 |  26.7  80.1  275   2  1  10.2   5.6
  5750  26.9  80.4  245   1  1  13.8   7.6 |  27.5  81.5  275   2  1  10.5   5.7
  5500  28.4  83.1  245   2  1  26.3  14.4 |  28.4  83.1  275   2  1  13.4   7.3
________________________________________________________________________________

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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