Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250115
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1915 MDT Monday, August 24, 2015

This forecast is for Tuesday, August 25, 2015:

If the trigger temperature of 86.0 F/30.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1424 ft/min (7.2 m/s)
   Maximum height of thermals.................. 19825 ft MSL (14518 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1130 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................. 11097 ft MSL (5790 ft AGL)
Thermal soaring outlook for Wednesday 08/26.... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 21811 ft MSL (16504 ft AGL)
Wave soaring outlook for Wednesday 08/26....... Poor

Remarks...

Sunrise/Sunset.................... 06:20:44 / 19:43:03 MDT
Total possible sunshine........... 13 hr 22 min 19 sec (802 min 19 sec)
Altitude of sun at 13:01:29 MDT... 60.89 degrees

Upper air data from numerical model forecast valid on 08/25/2015 at 0600 MDT

Freezing level.................. 15996 ft MSL (10689 ft AGL)
Convective condensation level... 16670 ft MSL (11363 ft AGL)
Lifted condensation level....... 17429 ft MSL (12122 ft AGL)
Lifted index.................... -3.8
K index......................... +22.6

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  -65.2 -85.4   290   38   19   1.8   1.0      M     M       M      M    M
 45000  -61.2 -78.2   295   58   30   4.6   2.5      M     M       M      M    M
 40000  -53.8 -64.8   300   73   37   6.9   3.8      M     M       M      M    M
 38000  -49.6 -57.3   300   64   33   6.9   3.8      M     M       M      M    M
 36000  -45.5 -49.9   300   55   28   6.9   3.8      M     M       M      M    M
 34000  -40.4 -40.7   305   47   24   7.5   4.1      M     M       M      M    M
 32000  -35.9 -32.6   305   39   20   7.7   4.2      M     M       M      M    M
 30000  -31.5 -24.7   310   33   17   7.2   4.0   43.7 110.6     7.5      M    M
 29000  -29.4 -20.9   315   31   16   7.2   4.0   42.8 109.0     6.8      M    M
 28000  -27.2 -17.0   320   28   14   7.6   4.2   41.9 107.5     6.3      M    M
 27000  -24.9 -12.8   320   25   13   7.6   4.2   41.0 105.8     5.6      M    M
 26000  -22.6  -8.7   325   22   11   7.6   4.2   40.2 104.4     5.0      M    M
 25000  -20.3  -4.5   330   19   10   7.2   4.0   39.6 103.2     4.5      M    M
 24000  -18.3  -0.9   325   18    9   6.9   3.8   38.4 101.1     3.6      M    M
 23000  -16.3   2.7   325   16    8   7.1   3.9   37.4  99.3     2.7      M    M
 22000  -14.3   6.3   320   15    8   7.1   3.9   36.5  97.7     1.9      M    M
 21000  -12.2  10.0   320   14    7   7.1   3.9   35.5  95.9     1.0      M    M
 20000  -10.1  13.8   315   13    7   7.1   3.9   34.6  94.2     0.2      M    M
 19500   -9.0  15.8   315   13    7   7.3   4.0   34.1  93.5    -0.2   1402  7.1
 19000   -7.9  17.8   310   12    6   8.5   4.6   33.8  92.9    -0.5   1352  6.9
 18500   -6.7  19.9   305   10    5   8.4   4.6   33.6  92.5    -0.7   1301  6.6
 18000   -5.5  22.1   300    9    5   8.5   4.7   33.4  92.1    -1.0   1250  6.4
 17500   -3.6  25.5   295    8    4   8.5   4.7   33.1  91.5    -1.3   1172  6.0
 17000   -2.3  27.9   285    6    3   8.7   4.8   32.9  91.2    -1.5   1120  5.7
 16500   -1.0  30.2   285    5    3   8.7   4.8   32.7  90.8    -1.7   1066  5.4
 16000    0.3  32.5   285    4    2   8.9   4.9   32.5  90.6    -1.9   1012  5.1
 15500    1.6  34.9   285    3    2   9.2   5.0   32.4  90.3    -2.0    957  4.9
 15000    3.0  37.4   285    3    2   9.2   5.0   32.3  90.2    -2.1    900  4.6
 14500    4.4  39.9   285    3    1   9.0   4.9   32.2  90.0    -2.2    844  4.3
 14000    5.8  42.4   290    2    1   9.0   4.9   32.1  89.8    -2.2    787  4.0
 13500    7.2  45.0   280    1    1   9.3   5.1   32.0  89.6    -2.3    731  3.7
 13000    8.6  47.5   265    2    1   9.3   5.1   31.9  89.4    -2.4    674  3.4
 12500    9.9  49.8   255    3    2   8.9   4.9   31.8  89.3    -2.5    619  3.1
 12000   11.2  52.2   245    4    2   8.8   4.8   31.6  89.0    -2.7    565  2.9
 11500   12.5  54.5   240    5    3   9.0   4.9   31.5  88.7    -2.9    512  2.6
 11000   13.8  56.8   235    6    3   9.1   5.0   31.4  88.5    -3.0    457  2.3
 10500   15.0  59.0   230    7    3   4.5   2.5   31.2  88.1    -3.3    407  2.1
 10250   15.3  59.5   230    7    4   7.6   4.2   30.7  87.3    -3.8    391  2.0
 10000   16.1  61.0   230    7    4  13.2   7.2   30.9  87.6    -3.7    358  1.8
  9750   17.0  62.6   225    8    4  11.6   6.3   31.1  87.9    -3.6    326  1.7
  9500   17.7  63.9   225    8    4   8.6   4.7   31.1  88.0    -3.6    297  1.5
  9250   18.2  64.8   225    8    4   7.2   3.9   30.9  87.7    -3.8    274  1.4
  9000   18.9  66.0   225    9    4  10.6   5.8   30.9  87.5    -3.9    247  1.3
  8750   19.7  67.5   225    9    5  11.2   6.2   31.0  87.8    -3.8    216  1.1
  8500   20.4  68.7   225   10    5   9.2   5.1   31.0  87.8    -3.9    186  0.9
  8250   21.0  69.8   225   11    6   8.4   4.6   30.9  87.7    -4.0    160  0.8
  8000   21.6  70.9   230   12    6   8.9   4.9   30.8  87.5    -4.1    135  0.7
  7750   22.3  72.1   230   13    7   8.2   4.5   30.8  87.4    -4.2    108  0.5
  7500   22.8  73.0   230   13    7   6.9   3.8   30.6  87.0    -4.4     84  0.4
  7250   23.3  73.9   230   13    7   6.7   3.7   30.3  86.6    -4.6     62  0.3
  7000   23.8  74.8   230   13    7   6.6   3.6   30.1  86.2    -4.9     40  0.2
  6750   24.2  75.6   230   14    7   4.4   2.4   29.8  85.7    -5.2     20  0.1
  6500   24.4  75.9   235   13    7   1.2   0.7   29.3  84.7    -5.7      6  0.0
  6250   24.6  76.3   240   13    6   6.5   3.5   28.7  83.7    -6.3      M    M
  6000   24.8  76.6   240   12    6 -11.7  -6.4   28.2  82.7    -6.8      M    M
  5750   22.6  72.7   235   11    6 -40.4 -22.1   25.2  77.4    -9.8     40  0.2
  5500   19.4  66.9   220    8    4 -33.8 -18.5   21.5  70.8   -13.7    126  0.6

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

           08/25/2015 at 0900 MDT          |       08/25/2015 at 1200 MDT
                                           |
K index... +21.0  LI... -1.1               | K index... +20.9  LI... -2.6
CAPE... +162.3  CIN... -49.0               | CAPE... +552.8  CIN... -44.9
                                           |
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 -65.5 -85.9  295  37 19   2.2   1.2 | -65.4 -85.7  295  37 19   1.9   1.1
 45000 -61.1 -78.0  300  54 28   4.6   2.5 | -61.4 -78.5  295  49 25   4.4   2.4
 40000 -53.8 -64.8  300  71 36   6.9   3.8 | -54.1 -65.4  300  62 32   7.4   4.0
 38000 -49.6 -57.3  300  63 32   6.9   3.8 | -49.6 -57.3  300  57 29   7.4   4.1
 36000 -45.5 -49.9  305  56 29   6.8   3.7 | -45.2 -49.4  305  52 27   7.4   4.1
 34000 -40.4 -40.7  310  46 24   7.6   4.2 | -40.4 -40.7  305  43 22   7.0   3.9
 32000 -35.8 -32.4  310  38 20   7.7   4.2 | -36.2 -33.2  310  35 18   7.3   4.0
 30000 -31.6 -24.9  315  33 17   7.0   3.8 | -31.8 -25.2  315  29 15   7.2   4.0
 29000 -29.5 -21.1  320  30 16   7.0   3.8 | -29.7 -21.5  315  27 14   7.2   4.0
 28000 -27.4 -17.3  320  28 14   8.0   4.4 | -27.4 -17.3  320  24 13   8.1   4.5
 27000 -25.0 -13.0  325  24 13   7.8   4.3 | -25.0 -13.0  320  22 11   8.0   4.4
 26000 -22.7  -8.9  325  21 11   7.9   4.3 | -22.6  -8.7  320  20 10   8.1   4.4
 25000 -20.3  -4.5  330  18  9   7.5   4.1 | -20.2  -4.4  325  18  9   8.0   4.4
 24000 -18.2  -0.8  325  16  8   7.3   4.0 | -17.8  -0.0  320  16  8   8.0   4.4
 23000 -16.0   3.2  325  15  8   7.4   4.1 | -15.4   4.3  315  14  7   8.0   4.4
 22000 -13.9   7.0  320  14  7   7.1   3.9 | -13.1   8.4  310  13  7   6.6   3.6
 21000 -11.8  10.8  320  14  7   6.9   3.8 | -11.3  11.7  310  13  7   6.3   3.5
 20000  -9.8  14.4  315  14  7   7.0   3.8 |  -9.4  15.1  315  12  6   6.4   3.5
 19500  -8.7  16.3  315  15  8   7.3   4.0 |  -8.5  16.7  315  12  6   7.0   3.8
 19000  -7.6  18.3  315  14  7   8.7   4.8 |  -7.3  18.9  315  12  6   8.5   4.7
 18500  -6.3  20.7  315  13  7   8.6   4.7 |  -6.1  21.0  315  11  6   8.5   4.6
 18000  -5.0  23.0  315  13  6   8.8   4.9 |  -4.2  24.4  315  10  5   9.1   5.0
 17500  -3.1  26.4  305  11  6   8.9   4.9 |  -2.9  26.8  315  10  5   9.1   5.0
 17000  -1.8  28.8  300  10  5   8.8   4.8 |  -1.6  29.1  315   9  5   9.0   4.9
 16500  -0.6  30.9  290  10  5   8.8   4.8 |  -0.2  31.6  310   9  4   9.0   4.9
 16000   0.7  33.3  280   9  5   8.9   4.9 |   1.1  34.0  305   8  4   9.0   5.0
 15500   2.0  35.6  275   8  4   9.1   5.0 |   2.4  36.3  300   7  4   9.1   5.0
 15000   3.4  38.1  265   8  4   9.0   5.0 |   3.8  38.8  295   6  3   9.1   5.0
 14500   4.7  40.5  255   7  4   8.6   4.7 |   5.1  41.2  280   6  3   8.9   4.9
 14000   6.0  42.8  245   6  3   8.6   4.7 |   6.4  43.5  265   5  3   9.0   4.9
 13500   7.3  45.1  240   6  3   9.2   5.0 |   7.8  46.0  250   5  3   8.8   4.8
 13000   8.7  47.7  235   5  3   9.2   5.0 |   9.1  48.4  245   5  2   8.7   4.8
 12500  10.1  50.2  235   5  3   9.3   5.1 |  10.4  50.7  240   5  2   9.2   5.0
 12000  11.6  52.9  230   5  3   9.3   5.1 |  11.8  53.2  230   4  2   9.3   5.1
 11500  12.9  55.2  230   5  3   8.8   4.8 |  13.1  55.6  225   4  2   8.9   4.9
 11000  14.2  57.6  225   6  3   8.7   4.8 |  14.4  57.9  220   4  2   8.9   4.9
 10500  15.4  59.7  225   6  3   4.0   2.2 |  15.5  59.9  215   4  2   3.9   2.1
 10250  15.7  60.3  225   6  3   7.6   4.2 |  15.8  60.4  215   4  2   7.7   4.2
 10000  16.5  61.7  220   6  3  13.3   7.3 |  16.7  62.1  210   4  2  12.9   7.1
  9750  17.4  63.3  220   6  3  11.4   6.3 |  17.5  63.5  205   5  2  11.0   6.0
  9500  18.1  64.6  215   6  3   8.4   4.6 |  18.2  64.8  205   5  2   8.3   4.5
  9250  18.6  65.5  215   7  3   7.0   3.8 |  18.8  65.8  200   5  2   7.5   4.1
  9000  19.2  66.6  215   7  3   9.9   5.4 |  19.4  66.9  200   4  2  10.2   5.6
  8750  20.0  68.0  215   7  3  10.5   5.7 |  20.2  68.4  195   4  2  10.3   5.7
  8500  20.6  69.1  215   7  3   9.3   5.1 |  20.9  69.6  195   4  2   8.6   4.7
  8250  21.3  70.3  215   6  3   8.6   4.7 |  21.5  70.7  195   4  2   8.1   4.5
  8000  21.9  71.4  215   6  3   9.6   5.3 |  22.1  71.8  190   3  2   8.2   4.5
  7750  22.7  72.9  220   6  3   8.8   4.8 |  22.7  72.9  190   3  1   8.2   4.5
  7500  23.2  73.8  220   6  3   6.5   3.5 |  23.3  73.9  185   2  1   8.6   4.7
  7250  23.6  74.5  225   6  3   5.7   3.1 |  23.9  75.0  180   2  1   8.4   4.6
  7000  24.0  75.2  225   6  3   7.5   4.1 |  24.5  76.1  160   1  0   9.3   5.1
  6750  24.5  76.1  230   6  3   0.8   0.4 |  25.1  77.2  095   1  0  10.3   5.6
  6500  24.2  75.6  240   6  3  -6.0  -3.3 |  25.9  78.6  080   1  0  10.3   5.7
  6250  23.8  74.8  250   5  3  -4.1  -2.2 |  26.6  79.9  070   1  0  10.1   5.5
  6000  23.5  74.3  260   5  3  -5.2  -2.9 |  27.4  81.3  055   1  0  11.0   6.0
  5750  23.0  73.4  250   4  2  -1.5  -0.8 |  28.3  82.9  050   1  0  16.1   8.8
  5500  23.1  73.6  240   4  2   6.3   3.5 |  29.8  85.6  055   1  0  21.8  11.9

           08/25/2015 at 1500 MDT          |       08/25/2015 at 1800 MDT
                                           |
K index... +22.5  LI... -1.6               | K index... +27.9  LI... -2.0
CAPE... +349.7  CIN... -18.8               | CAPE... +337.2  CIN... -15.7
                                           |
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 -65.2 -85.4  300  36 19   1.4   0.8 | -65.6 -86.1  305  38 20   0.9   0.5
 45000 -61.7 -79.1  300  49 25   4.2   2.3 | -62.6 -80.7  300  53 27   4.4   2.4
 40000 -54.1 -65.4  300  60 31   8.3   4.6 | -55.1 -67.2  300  63 32   9.2   5.1
 38000 -49.1 -56.4  295  55 28   8.3   4.6 | -49.5 -57.1  290  56 29   9.3   5.1
 36000 -44.1 -47.4  295  51 26   7.8   4.3 | -43.3 -45.9  285  50 26   7.7   4.2
 34000 -39.9 -39.8  300  44 23   7.0   3.8 | -39.1 -38.4  290  43 22   7.0   3.8
 32000 -35.7 -32.3  300  38 19   7.2   4.0 | -34.9 -30.8  300  37 19   7.6   4.2
 30000 -31.5 -24.7  305  31 16   7.2   3.9 | -30.4 -22.7  305  31 16   7.6   4.2
 29000 -29.3 -20.7  305  29 15   7.2   3.9 | -28.1 -18.6  305  29 15   7.6   4.2
 28000 -26.6 -15.9  310  25 13   7.7   4.2 | -25.9 -14.6  310  26 13   7.2   3.9
 27000 -24.3 -11.7  310  22 12   7.7   4.2 | -23.7 -10.7  310  23 12   7.2   4.0
 26000 -22.0  -7.6  315  20 10   7.7   4.2 | -21.6  -6.9  310  20 10   7.2   4.0
 25000 -19.7  -3.5  320  18  9   8.0   4.4 | -19.4  -2.9  315  17  9   7.2   4.0
 24000 -17.3   0.9  320  16  8   8.1   4.4 | -17.2   1.0  315  15  8   7.2   4.0
 23000 -14.9   5.2  320  14  7   8.1   4.4 | -15.1   4.8  320  12  6   7.2   4.0
 22000 -12.5   9.5  320  13  7   6.7   3.7 | -12.9   8.8  325  10  5   6.9   3.8
 21000 -10.6  12.9  320  13  7   6.7   3.7 | -11.0  12.2  335   9  5   6.8   3.7
 20000  -8.6  16.5  320  13  7   6.9   3.8 |  -9.0  15.8  350   8  4   6.9   3.8
 19500  -7.7  18.1  320  13  7   7.6   4.2 |  -8.0  17.6  355   7  4   7.3   4.0
 19000  -6.4  20.5  320  12  6   8.6   4.7 |  -6.8  19.8  005   6  3   8.7   4.8
 18500  -5.2  22.6  320  12  6   8.7   4.7 |  -4.9  23.2  030   4  2   8.6   4.7
 18000  -3.9  25.0  320  10  5   8.3   4.6 |  -3.7  25.3  060   3  2   8.5   4.7
 17500  -2.7  27.1  320   9  4   8.4   4.6 |  -2.4  27.7  095   4  2   8.6   4.7
 17000  -1.5  29.3  325   7  4   8.4   4.6 |  -1.2  29.8  115   5  3   8.6   4.7
 16500  -0.2  31.6  335   5  3   8.6   4.7 |   0.0  32.0  125   7  3   8.7   4.8
 16000   1.0  33.8  350   4  2   8.6   4.7 |   1.3  34.3  130   8  4   8.9   4.9
 15500   2.3  36.1  005   3  2   9.0   4.9 |   2.6  36.7  130   8  4   9.3   5.1
 15000   4.3  39.7  040   3  1   9.0   5.0 |   3.9  39.0  130   8  4   9.4   5.1
 14500   5.6  42.1  065   2  1   9.2   5.0 |   5.3  41.5  130   8  4   9.6   5.3
 14000   6.9  44.4  090   2  1   9.2   5.0 |   6.7  44.1  130   8  4   9.6   5.3
 13500   8.2  46.8  105   3  1   9.1   5.0 |   8.2  46.8  130   8  4   9.7   5.3
 13000   9.6  49.3  115   3  1   9.1   5.0 |   9.6  49.3  130   8  4   9.8   5.4
 12500  10.9  51.6  120   3  2   9.0   4.9 |  11.0  51.8  125   7  4   9.5   5.2
 12000  12.2  54.0  125   3  2   9.0   4.9 |  12.4  54.3  125   7  4   9.4   5.2
 11500  13.6  56.5  125   3  1   9.4   5.2 |  13.8  56.8  125   6  3   9.0   4.9
 11000  14.9  58.8  125   2  1   9.9   5.4 |  15.2  59.4  120   5  2   8.8   4.8
 10500  16.0  60.8  125   2  1   4.9   2.7 |  16.4  61.5  115   3  2   4.5   2.5
 10250  16.5  61.7  125   2  1   9.1   5.0 |  16.7  62.1  115   3  2   7.1   3.9
 10000  17.3  63.1  120   2  1  13.0   7.1 |  17.5  63.5  115   2  1  11.8   6.4
  9750  18.2  64.8  120   1  1  11.5   6.3 |  18.3  64.9  110   1  1  10.6   5.8
  9500  19.0  66.2  120   1  1   8.6   4.7 |  19.1  66.4  000   0  0   8.0   4.4
  9250  19.5  67.1  115   1  1   8.5   4.7 |  19.6  67.3  310   1  0   7.2   4.0
  9000  20.3  68.5  115   1  1  11.4   6.3 |  20.2  68.4  295   1  1  10.4   5.7
  8750  21.1  70.0  115   1  1  11.2   6.2 |  21.0  69.8  290   2  1  10.7   5.9
  8500  21.9  71.4  115   1  0  10.0   5.5 |  21.8  71.2  290   2  1   9.7   5.3
  8250  22.6  72.7  120   1  0   9.4   5.2 |  22.5  72.5  290   3  1   8.9   4.9
  8000  23.4  74.1  130   1  0  10.1   5.5 |  23.2  73.8  290   3  2   9.9   5.4
  7750  24.1  75.4  000   0  0  10.4   5.7 |  23.9  75.0  290   4  2  10.5   5.8
  7500  24.9  76.8  000   0  0  10.0   5.5 |  24.7  76.5  290   4  2   9.9   5.4
  7250  25.7  78.3  000   0  0  10.0   5.5 |  25.4  77.7  290   4  2   9.8   5.4
  7000  26.4  79.5  000   0  0  10.0   5.5 |  26.2  79.2  290   4  2   9.9   5.4
  6750  27.2  81.0  000   0  0  10.2   5.6 |  26.9  80.4  290   5  2  10.0   5.5
  6500  27.9  82.2  000   0  0  10.5   5.8 |  27.6  81.7  290   5  3  10.2   5.6
  6250  28.7  83.7  000   0  0  10.3   5.6 |  28.4  83.1  290   5  3  10.0   5.5
  6000  29.5  85.1  000   0  0  11.0   6.0 |  29.1  84.4  290   5  3  10.6   5.8
  5750  30.4  86.7  000   0  0  16.2   8.9 |  30.0  86.0  290   5  3  12.6   6.9
  5500  31.9  89.4  315   1  0  22.6  12.4 |  31.0  87.8  290   5  3  14.0   7.7
________________________________________________________________________________

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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