Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 261241
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0641 MDT Wednesday, August 26, 2015

This forecast is for Wednesday, August 26, 2015:

If the trigger temperature of 88.3 F/31.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 837 ft/min (4.3 m/s)
   Maximum height of thermals.................. 16146 ft MSL (10861 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7982 ft MSL (2697 ft AGL)
Thermal soaring outlook for Thursday 08/27..... Good

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)................ Weak PVA
Potential height of wave....................... 16347 ft MSL (11062 ft AGL)
Wave soaring outlook for Thursday 08/27........ Poor

Remarks...

Sunrise/Sunset.................... 06:21:40 / 19:41:34 MDT
Total possible sunshine........... 13 hr 19 min 54 sec (799 min 54 sec)
Altitude of sun at 13:01:13 MDT... 60.55 degrees

Upper air data from rawinsonde observation taken on 08/26/2015 at 0600 MDT

Freezing level.................. 16695 ft MSL (11410 ft AGL)
Convective condensation level... 18455 ft MSL (13170 ft AGL)
Lifted condensation level....... 17936 ft MSL (12651 ft AGL)
Lifted index.................... -1.0
K index......................... +19.1

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  -65.6 -86.1   305   35   18   5.6   3.1   83.4 182.2    29.2      M    M
 45000  -61.6 -78.9   300   50   25  -7.1  -3.9   65.9 150.6    20.3      M    M
 40000  -54.3 -65.7   295   57   29   7.3   4.0   53.2 127.7    13.3      M    M
 38000  -49.4 -56.9   295   49   25   8.8   4.8   51.9 125.3    12.8      M    M
 36000  -44.6 -48.3   300   44   23   7.2   4.0   50.4 122.7    12.1      M    M
 34000  -39.6 -39.3   295   34   18   8.5   4.7   49.2 120.6    11.5      M    M
 32000  -34.9 -30.8   310   24   13   7.7   4.2   47.6 117.6    10.5      M    M
 30000  -31.3 -24.3   315   17    9   3.2   1.7   44.6 112.3     8.5      M    M
 29000  -28.7 -19.7   310   15    8   9.2   5.0   43.3 110.0     7.6      M    M
 28000  -26.1 -15.0   305   14    7   7.2   3.9   43.0 109.3     7.4      M    M
 27000  -23.4 -10.1   300   10    5   9.2   5.0   42.5 108.6     7.2      M    M
 26000  -21.8  -7.2   290    6    3   6.4   3.5   41.1 105.9     6.0      M    M
 25000  -19.5  -3.1   240   13    7   7.6   4.2   40.3 104.5     5.4      M    M
 24000  -17.1   1.2   235   12    6   8.2   4.5   39.8 103.6     5.0      M    M
 23000  -14.6   5.7   235   10    5   6.3   3.4   39.1 102.4     4.6      M    M
 22000  -13.1   8.4   230    9    5   5.2   2.9   37.5  99.4     3.2      M    M
 21000  -11.3  11.7   225    8    4   8.9   4.9   36.2  97.2     2.1      M    M
 20000   -8.8  16.2   215    7    4   8.6   4.7   35.8  96.5     1.8      M    M
 19500   -7.6  18.3   190    6    3   8.8   4.8   35.6  96.1     1.6      M    M
 19000   -6.2  20.8   185    7    4   9.1   5.0   35.5  95.8     1.5      M    M
 18500   -4.8  23.4   185    8    4   9.1   5.0   35.3  95.6     1.4      M    M
 18000   -3.5  25.7   185    9    5   9.1   5.0   35.2  95.4     1.3      M    M
 17500   -2.1  28.2   185   10    5   9.1   5.0   35.1  95.3     1.2      M    M
 17000   -0.7  30.7   180   11    6   8.1   4.4   35.1  95.2     1.2      M    M
 16500    0.2  32.4   180   12    6   5.8   3.2   34.5  94.1     0.6      M    M
 16000    1.0  33.8   180   13    7   7.3   4.0   33.8  92.9    -0.1   1034  5.3
 15500    2.3  36.1   180   12    6   9.2   5.1   33.7  92.7    -0.2    979  5.0
 15000    3.7  38.7   180   11    6   9.3   5.1   33.7  92.6    -0.3    923  4.7
 14500    5.7  42.3   180    9    5   9.3   5.1   33.6  92.5    -0.3    839  4.3
 14000    7.1  44.8   185    8    4   9.3   5.1   33.6  92.4    -0.4    784  4.0
 13500    8.5  47.3   200    6    3   9.3   5.1   33.5  92.3    -0.5    728  3.7
 13000    9.8  49.6   220    5    3   9.3   5.1   33.4  92.2    -0.6    672  3.4
 12500   11.2  52.2   215    7    3   9.3   5.1   33.3  92.0    -0.7    616  3.1
 12000   12.6  54.7   215    8    4   9.3   5.1   33.3  91.9    -0.8    560  2.8
 11500   13.9  57.0   215    9    5   9.3   5.1   33.1  91.7    -0.9    504  2.6
 11000   15.3  59.5   220    9    5   9.4   5.1   33.1  91.5    -1.0    448  2.3
 10500   16.6  61.9   225   10    5   8.6   4.7   32.9  91.3    -1.2    393  2.0
 10250   17.3  63.1   235   12    6   8.1   4.4   32.8  91.1    -1.3    367  1.9
 10000   17.9  64.2   240   13    7   7.6   4.2   32.7  90.8    -1.4    342  1.7
  9750   18.4  65.1   240   15    8   7.3   4.0   32.5  90.5    -1.6    319  1.6
  9500   18.9  66.0   235   16    8   7.4   4.1   32.3  90.2    -1.8    296  1.5
  9250   19.5  67.1   235   18    9   7.4   4.0   32.1  89.8    -2.0    272  1.4
  9000   20.0  68.0   235   19   10   7.4   4.1   32.0  89.5    -2.2    249  1.3
  8750   20.5  68.9   235   19   10   7.4   4.1   31.8  89.2    -2.4    225  1.1
  8500   21.1  70.0   230   18   10   7.4   4.1   31.6  88.9    -2.6    202  1.0
  8250   21.6  70.9   230   18    9   7.4   4.1   31.4  88.5    -2.8    178  0.9
  8000   22.1  71.8   230   18    9   7.4   4.1   31.2  88.2    -3.0    155  0.8
  7750   22.7  72.9   230   17    9   7.2   4.0   31.0  87.9    -3.2    131  0.7
  7500   23.2  73.8   225   16    8   8.1   4.4   30.8  87.5    -3.4    108  0.5
  7250   23.7  74.7   225   16    8   4.8   2.6   30.7  87.2    -3.6     85  0.4
  7000   23.7  74.7   220   15    8  -5.6  -3.1   29.9  85.8    -4.4     78  0.4
  6750   23.2  73.8   220   16    8  -4.4  -2.4   28.6  83.5    -5.6     86  0.4
  6500   23.3  73.9   220   16    8   6.6   3.6   28.0  82.4    -6.3     75  0.4
  6250   23.8  74.8   220   17    9   4.1   2.3   27.8  82.0    -6.5     53  0.3
  6000   23.8  74.8   220   18    9  -2.1  -1.2   27.1  80.7    -7.3     47  0.2
  5750   23.3  73.9   220   13    7 -13.1  -7.2   25.9  78.6    -8.6     55  0.3
  5500   21.3  70.3   215    8    4 -40.3 -22.1   23.2  73.8   -11.3    107  0.5

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

           08/26/2015 at 0900 MDT          |       08/26/2015 at 1200 MDT
                                           |
K index... +24.1  LI... -0.0               | K index... +24.8  LI... -2.5
CAPE... +24.6  CIN... -47.3                | CAPE... +558.8  CIN... -35.4
                                           |
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 -65.2 -85.4  315  31 16   2.5   1.4 | -65.2 -85.4  315  31 16   3.0   1.6
 45000 -60.8 -77.4  305  49 25   3.9   2.1 | -60.3 -76.5  305  47 24   3.4   1.9
 40000 -53.8 -64.8  295  55 28   7.5   4.1 | -54.1 -65.4  285  54 28   8.0   4.4
 38000 -49.3 -56.7  295  44 23   7.5   4.1 | -49.3 -56.7  285  43 22   8.0   4.4
 36000 -44.8 -48.6  305  34 18   7.9   4.4 | -44.5 -48.1  290  32 16   8.2   4.5
 34000 -39.8 -39.6  305  28 15   8.5   4.7 | -39.4 -38.9  295  26 13   8.5   4.7
 32000 -34.7 -30.5  305  23 12   9.1   5.0 | -33.7 -28.7  305  19 10   8.6   4.7
 30000 -30.4 -22.7  295  17  9   7.1   3.9 | -29.0 -20.2  290  16  8   7.8   4.3
 29000 -27.7 -17.9  285  13  7   7.1   3.9 | -26.7 -16.1  285  15  8   7.8   4.3
 28000 -25.6 -14.1  275  11  6   7.2   3.9 | -24.5 -12.1  275  13  7   6.5   3.6
 27000 -23.5 -10.3  265   9  5   7.2   3.9 | -22.5  -8.5  255  10  5   6.6   3.6
 26000 -21.4  -6.5  250   7  4   7.2   4.0 | -20.6  -5.1  230  10  5   6.6   3.6
 25000 -19.2  -2.6  225   6  3   7.1   3.9 | -18.7  -1.7  205  11  5   6.3   3.5
 24000 -17.1   1.2  220   6  3   7.1   3.9 | -16.8   1.8  200  10  5   6.3   3.4
 23000 -15.0   5.0  210   6  3   7.1   3.9 | -15.0   5.0  190   9  4   6.3   3.5
 22000 -12.9   8.8  200   6  3   7.5   4.1 | -13.1   8.4  180   8  4   7.5   4.1
 21000 -10.7  12.7  200   8  4   7.6   4.1 | -10.8  12.6  190   8  4   7.7   4.2
 20000  -8.5  16.7  200   9  5   7.6   4.2 |  -8.5  16.7  200   8  4   7.7   4.2
 19500  -7.4  18.7  200  10  5   7.8   4.3 |  -7.3  18.9  205   9  4   7.8   4.3
 19000  -6.2  20.8  205  11  6   8.2   4.5 |  -6.1  21.0  205  10  5   8.0   4.4
 18500  -5.0  23.0  205  12  6   8.2   4.5 |  -5.0  23.0  200  11  5   8.0   4.4
 18000  -3.8  25.2  210  13  7   8.4   4.6 |  -3.8  25.2  205  12  6   8.4   4.6
 17500  -2.5  27.5  210  13  7   8.4   4.6 |  -2.6  27.3  210  13  6   8.4   4.6
 17000  -1.3  29.7  210  14  7   8.5   4.7 |  -1.4  29.5  215  14  7   8.4   4.6
 16500  -0.0  32.0  210  14  7   8.6   4.7 |   0.3  32.5  215  15  8   8.0   4.4
 16000   1.2  34.2  205  14  7   8.6   4.7 |   1.5  34.7  215  16  8   8.3   4.5
 15500   3.0  37.4  205  14  7   8.6   4.7 |   2.8  37.0  220  16  8   8.5   4.7
 15000   4.3  39.7  200  14  7   8.6   4.7 |   4.0  39.2  220  17  9   8.6   4.7
 14500   5.6  42.1  205  14  7   9.0   5.0 |   5.4  41.7  220  17  9   9.3   5.1
 14000   6.9  44.4  205  14  7   9.0   5.0 |   6.7  44.1  220  18  9   9.2   5.1
 13500   8.2  46.8  210  14  7   9.0   4.9 |   8.1  46.6  220  19 10   9.2   5.1
 13000   9.6  49.3  210  14  7   9.0   4.9 |   9.5  49.1  220  19 10   9.2   5.0
 12500  10.9  51.6  210  14  7   9.2   5.1 |  10.9  51.6  220  19 10   9.5   5.2
 12000  12.3  54.1  210  14  7   9.3   5.1 |  12.3  54.1  215  19 10   9.6   5.2
 11500  13.7  56.7  210  14  7   9.1   5.0 |  13.7  56.7  215  19 10   9.2   5.1
 11000  15.0  59.0  210  14  7   9.2   5.0 |  15.0  59.0  215  19 10   9.3   5.1
 10500  16.2  61.2  210  15  8   4.2   2.3 |  16.2  61.2  215  19 10   4.6   2.5
 10250  16.5  61.7  210  15  8   7.3   4.0 |  16.6  61.9  215  19 10   7.4   4.1
 10000  17.3  63.1  210  15  8  11.9   6.6 |  17.3  63.1  215  19 10  11.7   6.4
  9750  18.1  64.6  210  15  8  10.4   5.7 |  18.1  64.6  220  18  9  10.4   5.7
  9500  18.8  65.8  210  15  8   7.9   4.3 |  18.8  65.8  220  18  9   8.3   4.5
  9250  19.3  66.7  210  15  8   7.1   3.9 |  19.4  66.9  220  18  9   7.5   4.1
  9000  19.9  67.8  210  15  8   9.7   5.3 |  20.0  68.0  215  18  9   9.4   5.1
  8750  20.7  69.3  210  15  8   9.8   5.4 |  20.7  69.3  215  17  9   9.4   5.2
  8500  21.3  70.3  210  15  8   8.0   4.4 |  21.3  70.3  215  17  8   8.8   4.8
  8250  21.9  71.4  210  15  8   6.9   3.8 |  21.9  71.4  215  15  8   8.4   4.6
  8000  22.4  72.3  210  15  8   8.4   4.6 |  22.5  72.5  215  14  7   9.3   5.1
  7750  23.1  73.6  210  15  8   8.7   4.8 |  23.1  73.6  210  13  7  10.1   5.6
  7500  23.6  74.5  210  15  8   7.2   3.9 |  23.8  74.8  210  13  7   9.9   5.4
  7250  24.1  75.4  210  15  8   6.3   3.5 |  24.6  76.3  210  12  6  10.0   5.5
  7000  24.6  76.3  215  15  8   8.7   4.8 |  25.3  77.5  210  12  6   9.7   5.3
  6750  25.3  77.5  215  16  8   3.1   1.7 |  26.0  78.8  210  12  6  10.0   5.5
  6500  25.0  77.0  215  14  7  -4.0  -2.2 |  26.8  80.2  210  12  6  10.5   5.8
  6250  24.8  76.6  220  13  7  -2.4  -1.3 |  27.6  81.7  210  11  6  10.3   5.6
  6000  24.5  76.1  225  11  6  -3.9  -2.1 |  28.4  83.1  210  11  6  11.0   6.1
  5750  24.1  75.4  220   8  4  -1.3  -0.7 |  29.4  84.9  210  10  5  16.1   8.9
  5500  24.2  75.6  220   6  3   6.0   3.3 |  30.8  87.4  210  10  5  22.2  12.2

           08/26/2015 at 1500 MDT          |       08/26/2015 at 1800 MDT
                                           |
K index... +21.6  LI... -1.1               | K index... +24.6  LI... -1.2
CAPE... +161.9  CIN... -24.1               | CAPE... +95.6  CIN... -19.7
                                           |
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 -65.3 -85.5  310  35 18   3.8   2.1 | -66.1 -87.0  305  38 19   3.0   1.7
 45000 -59.7 -75.5  300  48 25   2.9   1.6 | -60.7 -77.3  300  53 27   4.1   2.3
 40000 -53.8 -64.8  285  48 25   8.8   4.8 | -53.3 -63.9  285  53 27   8.8   4.8
 38000 -48.6 -55.5  280  38 20   8.7   4.8 | -48.0 -54.4  285  47 24   8.8   4.8
 36000 -43.3 -45.9  270  29 15   8.7   4.8 | -42.8 -45.0  285  40 21   8.8   4.9
 34000 -38.1 -36.6  265  24 12   8.7   4.8 | -37.4 -35.3  285  35 18   8.9   4.9
 32000 -32.9 -27.2  260  18  9   9.5   5.2 | -32.1 -25.8  285  31 16   9.6   5.3
 30000 -28.1 -18.6  250  13  7   7.0   3.9 | -26.8 -16.2  270  23 12   7.8   4.3
 29000 -26.0 -14.8  240  11  5   7.0   3.9 | -24.5 -12.1  260  20 10   7.8   4.3
 28000 -24.0 -11.2  230  10  5   6.3   3.5 | -22.4  -8.3  250  17  9   5.0   2.8
 27000 -22.1  -7.8  220  11  5   6.4   3.5 | -20.9  -5.6  235  17  9   5.2   2.9
 26000 -20.2  -4.4  210  12  6   6.4   3.5 | -19.3  -2.7  220  17  9   5.2   2.9
 25000 -18.3  -0.9  200  13  7   6.2   3.4 | -17.8  -0.0  205  18  9   5.4   2.9
 24000 -16.5   2.3  200  15  8   6.2   3.4 | -16.1   3.0  200  18  9   5.5   3.0
 23000 -14.6   5.7  195  16  8   6.2   3.4 | -14.5   5.9  195  19 10   5.5   3.0
 22000 -12.7   9.1  195  17  9   7.6   4.2 | -12.8   9.0  190  19 10   6.8   3.7
 21000 -10.3  13.5  190  18  9   7.9   4.3 | -10.6  12.9  190  19 10   7.4   4.0
 20000  -8.0  17.6  185  19 10   7.9   4.3 |  -8.4  16.9  190  18  9   7.4   4.1
 19500  -6.8  19.8  185  19 10   7.9   4.3 |  -7.4  18.7  195  18  9   7.5   4.1
 19000  -5.6  21.9  185  19 10   7.8   4.3 |  -6.2  20.8  195  18  9   7.7   4.2
 18500  -4.4  24.1  185  19 10   7.8   4.3 |  -5.1  22.8  195  18  9   7.7   4.2
 18000  -3.3  26.1  185  19 10   8.2   4.5 |  -3.9  25.0  200  18  9   7.9   4.4
 17500  -2.1  28.2  190  19 10   8.3   4.5 |  -2.8  27.0  200  18  9   8.0   4.4
 17000  -0.9  30.4  190  19 10   8.4   4.6 |  -1.6  29.1  200  18  9   8.1   4.5
 16500   0.4  32.7  195  19 10   8.5   4.7 |  -0.4  31.3  200  17  9   8.6   4.7
 16000   2.2  36.0  200  18  9   8.6   4.7 |   1.4  34.5  200  16  8   9.0   4.9
 15500   3.4  38.1  200  19 10   8.7   4.8 |   2.7  36.9  195  16  8   9.6   5.3
 15000   4.7  40.5  205  19 10   8.7   4.8 |   4.1  39.4  195  15  8   9.6   5.3
 14500   5.9  42.6  205  19 10   8.4   4.6 |   5.5  41.9  195  15  8   9.4   5.2
 14000   7.1  44.8  205  19 10   8.4   4.6 |   6.9  44.4  190  15  8   9.5   5.2
 13500   8.3  46.9  200  18  9   9.1   5.0 |   8.3  46.9  190  15  8   9.4   5.2
 13000   9.6  49.3  200  17  9   9.2   5.0 |   9.7  49.5  190  15  8   9.4   5.2
 12500  10.9  51.6  200  17  9   9.2   5.0 |  11.1  52.0  185  15  8   9.5   5.2
 12000  12.2  54.0  200  16  8   9.2   5.0 |  12.5  54.5  185  15  8   9.6   5.2
 11500  13.6  56.5  200  15  8   9.5   5.2 |  13.9  57.0  180  16  8   9.6   5.3
 11000  15.0  59.0  200  14  7   9.8   5.3 |  15.4  59.7  180  16  8   9.4   5.2
 10500  16.3  61.3  200  14  7   5.7   3.1 |  16.8  62.2  180  16  8   5.4   2.9
 10250  16.7  62.1  200  14  7   8.5   4.7 |  17.1  62.8  180  16  8   6.7   3.7
 10000  17.6  63.7  200  14  7  13.0   7.1 |  17.9  64.2  180  16  8  13.0   7.1
  9750  18.5  65.3  200  14  7  12.0   6.6 |  18.8  65.8  180  16  8  12.1   6.7
  9500  19.4  66.9  200  14  7   8.9   4.9 |  19.7  67.5  180  16  8   9.3   5.1
  9250  19.9  67.8  200  14  7   8.0   4.4 |  20.2  68.4  180  15  8   7.6   4.2
  9000  20.7  69.3  200  13  7  11.1   6.1 |  20.9  69.6  180  15  8  10.6   5.8
  8750  21.5  70.7  200  13  7  11.2   6.1 |  21.7  71.1  180  14  7  10.6   5.8
  8500  22.3  72.1  200  13  7  10.4   5.7 |  22.5  72.5  180  14  7  10.4   5.7
  8250  23.0  73.4  200  13  7   9.9   5.4 |  23.2  73.8  180  13  7  10.2   5.6
  8000  23.8  74.8  200  13  7   9.8   5.4 |  24.0  75.2  180  12  6   9.8   5.4
  7750  24.5  76.1  200  13  7   9.8   5.4 |  24.7  76.5  180  11  6   9.4   5.2
  7500  25.3  77.5  200  13  6  10.2   5.6 |  25.4  77.7  180  10  5   9.6   5.3
  7250  26.0  78.8  200  12  6  10.4   5.7 |  26.1  79.0  180   9  5   9.7   5.3
  7000  26.8  80.2  200  12  6  10.0   5.5 |  26.8  80.2  185   8  4   9.5   5.2
  6750  27.5  81.5  200  12  6  10.0   5.5 |  27.5  81.5  185   7  4   9.5   5.2
  6500  28.3  82.9  200  12  6  10.5   5.8 |  28.2  82.8  185   7  4  10.0   5.5
  6250  29.1  84.4  205  12  6  11.2   6.1 |  29.0  84.2  185   6  3  10.4   5.7
  6000  29.9  85.8  205  11  6   9.1   5.0 |  29.8  85.6  190   6  3   9.5   5.2
  5750  30.6  87.1  205  11  6  13.7   7.5 |  30.4  86.7  190   5  3  10.8   5.9
  5500  32.1  89.8  205  11  5  27.2  14.9 |  31.4  88.5  190   5  2  15.7   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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