Soaring Guidance
Issued by NWS Denver/Boulder, CO

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266
UXUS97 KBOU 201337
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0737 MDT Tuesday, June 20, 2017

This forecast is for Tuesday, June 20, 2017:

If the trigger temperature of 84.4 F/29.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 811 ft/min (4.1 m/s)
   Maximum height of thermals.................. 15260 ft MSL (9975 ft AGL)

Forecast maximum temperature................... 96.0 F/36.0 C
Time of trigger temperature.................... 1015 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................. 13244 ft MSL (7958 ft AGL)
Thermal soaring outlook for Wednesday 06/21.... Excellent

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 14881 ft MSL (9596 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 15373 ft MSL (10088 ft AGL)
Wave soaring outlook for Wednesday 06/21....... Poor

Remarks...

Sunrise/Sunset.................... 05:31:38 / 20:30:34 MDT
Total possible sunshine........... 14 hr 58 min 56 sec (898 min 56 sec)
Altitude of sun at 13:01:13 MDT... 73.64 degrees

Upper air data from rawinsonde observation taken on 06/20/2017 at 0600 MDT

Freezing level.................. 17344 ft MSL (12059 ft AGL)
Convective condensation level... 18798 ft MSL (13513 ft AGL)
Lifted condensation level....... 18445 ft MSL (13160 ft AGL)
Lifted index.................... -2.7
K index......................... -14.9

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  -69.2 -92.6   315   49   25   5.5   3.0   78.2 172.7    24.8      M    M
 45000  -64.7 -84.5   305   49   25   6.5   3.5   60.1 140.1    15.4      M    M
 40000  -55.1 -67.2   305   49   25   4.9   2.7   52.3 126.2    11.3      M    M
 38000  -51.0 -59.8   300   49   25   8.7   4.8   49.7 121.5     9.7      M    M
 36000  -45.7 -50.3   295   49   25   9.2   5.0   49.0 120.2     9.5      M    M
 34000  -41.0 -41.8   295   50   26   7.9   4.3   47.4 117.3     8.6      M    M
 32000  -36.3 -33.3   300   53   27   7.1   3.9   45.8 114.5     7.6      M    M
 30000  -30.6 -23.1   295   45   23   8.7   4.8   44.7 112.5     7.0      M    M
 29000  -28.3 -18.9   295   40   21   7.3   4.0   43.9 111.0     6.4      M    M
 28000  -26.1 -15.0   295   36   19   7.3   4.0   42.9 109.3     5.7      M    M
 27000  -23.9 -11.0   295   32   16   7.3   4.0   42.1 107.8     5.2      M    M
 26000  -21.7  -7.1   295   31   16   7.3   4.0   41.1 106.0     4.4      M    M
 25000  -19.5  -3.1   295   31   16   8.0   4.4   40.2 104.4     3.7      M    M
 24000  -17.1   1.2   290   29   15   8.3   4.6   39.6 103.4     3.2      M    M
 23000  -14.6   5.7   290   27   14   8.4   4.6   39.2 102.5     2.9      M    M
 22000  -12.0  10.4   285   26   13   8.2   4.5   38.8 101.9     2.6      M    M
 21000   -9.7  14.5   280   24   12   7.1   3.9   37.9 100.2     2.0      M    M
 20000   -7.1  19.2   285   23   12   9.0   4.9   37.5  99.5     1.7      M    M
 19500   -5.8  21.6   290   23   12   8.9   4.9   37.4  99.3     1.6      M    M
 19000   -4.5  23.9   290   23   12   8.5   4.7   37.1  98.9     1.4      M    M
 18500   -3.2  26.2   295   23   12   8.5   4.7   36.9  98.4     1.1      M    M
 18000   -1.9  28.6   295   23   12   8.5   4.7   36.7  98.0     1.0      M    M
 17500   -0.6  30.9   300   23   12   8.5   4.7   36.5  97.6     0.8      M    M
 17000    0.6  33.1   300   24   12   8.5   4.7   36.3  97.3     0.6      M    M
 16500    1.9  35.4   300   24   12   8.5   4.7   36.1  97.1     0.5      M    M
 16000    3.2  37.8   305   24   12   8.6   4.7   36.0  96.8     0.4      M    M
 15500    4.5  40.1   305   25   13   8.6   4.7   35.8  96.4     0.2      M    M
 15000    5.8  42.4   310   26   13   1.7   1.0   34.8  94.7    -0.7    787  4.0
 14500    6.1  43.0   315   24   12   2.4   1.3   33.6  92.5    -1.9    764  3.9
 14000    6.8  44.2   315   23   12   8.6   4.7   33.0  91.4    -2.6    726  3.7
 13500    8.0  46.4   325   21   11   8.1   4.4   32.7  90.9    -2.9    677  3.4
 13000    9.2  48.6   330   20   10   8.1   4.4   32.5  90.4    -3.2    627  3.2
 12500   10.3  50.5   325   18    9   8.1   4.5   32.2  89.9    -3.5    577  2.9
 12000   11.5  52.7   325   17    9   8.2   4.5   31.9  89.5    -3.8    528  2.7
 11500   12.7  54.9   325   17    9   8.2   4.5   31.6  89.0    -4.2    478  2.4
 11000   13.8  56.8   320   17    9   8.2   4.5   31.4  88.5    -4.5    428  2.2
 10500   15.0  59.0   320   17    9   7.4   4.0   31.2  88.1    -4.8    378  1.9
 10250   15.4  59.7   320   16    8   6.2   3.4   30.9  87.6    -5.1    357  1.8
 10000   15.9  60.6   320   14    7   6.5   3.5   30.6  87.1    -5.4    336  1.7
  9750   16.4  61.5   320   12    6   6.4   3.5   30.4  86.7    -5.7    315  1.6
  9500   16.8  62.2   320   11    6   6.4   3.5   30.1  86.2    -6.0    294  1.5
  9250   17.3  63.1   325    9    5   6.4   3.5   29.9  85.8    -6.2    273  1.4
  9000   17.7  63.9   325    8    4   6.4   3.5   29.6  85.3    -6.5    252  1.3
  8750   18.2  64.8   315    7    4   6.5   3.6   29.4  84.8    -6.8    231  1.2
  8500   18.6  65.5   305    7    3   6.3   3.5   29.1  84.4    -7.1    210  1.1
  8250   19.1  66.4   295    6    3   7.1   3.9   28.8  83.9    -7.4    189  1.0
  8000   19.5  67.1   285    6    3   4.2   2.3   28.6  83.5    -7.7    168  0.9
  7750   19.6  67.3   280    6    3   0.7   0.4   28.0  82.3    -8.4    159  0.8
  7500   19.6  67.3   270    6    3   1.1   0.6   27.3  81.1    -9.1    151  0.8
  7250   19.6  67.3   265    6    3   1.4   0.8   26.6  80.0    -9.9    144  0.7
  7000   19.7  67.5   260    6    3   2.4   1.3   26.0  78.9   -10.6    134  0.7
  6750   19.9  67.8   255    6    3   2.7   1.5   25.5  77.9   -11.1    121  0.6
  6500   20.1  68.2   250    6    3   2.8   1.6   25.0  76.9   -11.7    108  0.5
  6250   20.3  68.5   245    7    3   2.0   1.1   24.4  76.0   -12.2     94  0.5
  6000   20.2  68.4   240    7    4  -5.1  -2.8   23.6  74.5   -13.1     89  0.5
  5750   19.5  67.1   235    6    3  -8.4  -4.6   22.3  72.1   -14.5    102  0.5
  5500   18.9  66.0   230    5    3 -10.2  -5.6   20.9  69.7   -15.9    114  0.6

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

           06/20/2017 at 0900 MDT          |       06/20/2017 at 1200 MDT
                                           |
K index... +14.7  LI... +2.3               | K index... +18.3  LI... +0.8
CAPE... +7.5  CIN... -121.2                | CAPE... +59.7  CIN... -122.7
                                           |
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  325  36 19   0.2   0.1 | -64.6 -84.3  335  27 14   0.0   0.0
 45000 -62.8 -81.0  315  46 24   4.6   2.5 | -62.5 -80.5  325  37 19   4.5   2.5
 40000 -55.3 -67.5  310  46 24   8.0   4.4 | -55.1 -67.2  315  36 18   7.8   4.3
 38000 -50.4 -58.7  310  46 24   8.0   4.4 | -50.4 -58.7  310  37 19   7.9   4.3
 36000 -45.6 -50.1  310  46 23   8.0   4.4 | -45.1 -49.2  310  38 20   8.2   4.5
 34000 -40.1 -40.2  305  42 22   8.3   4.5 | -40.1 -40.2  305  35 18   8.4   4.6
 32000 -35.1 -31.2  305  39 20   8.4   4.6 | -35.0 -31.0  300  33 17   8.6   4.7
 30000 -30.9 -23.6  300  37 19   7.0   3.8 | -30.6 -23.1  295  33 17   7.3   4.0
 29000 -28.8 -19.8  300  36 19   7.0   3.8 | -28.4 -19.1  295  34 17   7.3   4.0
 28000 -26.6 -15.9  295  35 18   7.7   4.3 | -26.2 -15.2  290  34 17   7.0   3.9
 27000 -24.3 -11.7  295  34 18   7.7   4.2 | -24.1 -11.4  290  33 17   7.1   3.9
 26000 -22.0  -7.6  295  33 17   7.7   4.2 | -21.9  -7.4  290  33 17   7.1   3.9
 25000 -19.7  -3.5  295  32 16   8.2   4.5 | -19.8  -3.6  285  33 17   7.5   4.1
 24000 -17.1   1.2  295  31 16   8.6   4.7 | -17.4   0.7  290  31 16   7.9   4.3
 23000 -14.6   5.7  295  30 15   8.7   4.7 | -15.1   4.8  290  29 15   7.9   4.4
 22000 -12.0  10.4  295  29 15   8.1   4.5 | -12.8   9.0  295  27 14   8.1   4.5
 21000  -9.6  14.7  295  27 14   7.9   4.4 | -10.3  13.5  295  26 14   8.2   4.5
 20000  -7.3  18.9  300  24 13   7.9   4.4 |  -7.9  17.8  300  26 13   8.3   4.5
 19500  -6.1  21.0  300  23 12   7.9   4.3 |  -6.7  19.9  300  26 13   8.3   4.6
 19000  -4.9  23.2  305  22 11   7.7   4.2 |  -5.4  22.3  305  25 13   8.7   4.8
 18500  -3.8  25.2  310  21 11   7.8   4.3 |  -3.5  25.7  305  24 12   8.7   4.8
 18000  -2.7  27.1  310  21 11   7.8   4.3 |  -2.3  27.9  305  23 12   8.0   4.4
 17500  -1.5  29.3  315  20 10   7.9   4.3 |  -1.1  30.0  305  21 11   8.1   4.4
 17000   0.2  32.4  320  20 10   7.6   4.2 |   0.1  32.2  305  20 10   8.1   4.4
 16500   1.3  34.3  320  20 10   7.6   4.2 |   1.3  34.3  305  20 10   8.1   4.4
 16000   2.4  36.3  325  20 10   7.7   4.2 |   2.5  36.5  310  20 10   8.2   4.5
 15500   3.6  38.5  325  20 10   8.0   4.4 |   3.7  38.7  310  20 10   8.6   4.7
 15000   4.7  40.5  325  20 10   8.1   4.4 |   4.9  40.8  310  21 11   8.6   4.7
 14500   5.8  42.4  325  20 10   8.0   4.4 |   6.2  43.2  310  21 11   8.5   4.7
 14000   7.0  44.6  320  19 10   8.1   4.4 |   7.4  45.3  310  20 10   8.5   4.7
 13500   8.2  46.8  320  18  9   8.1   4.5 |   8.7  47.7  310  19 10   8.5   4.7
 13000   9.4  48.9  320  17  9   8.2   4.5 |   9.9  49.8  310  19 10   8.5   4.7
 12500  10.6  51.1  320  15  8   8.3   4.6 |  11.1  52.0  310  18  9   8.0   4.4
 12000  11.8  53.2  325  14  7   8.4   4.6 |  12.3  54.1  310  16  8   7.8   4.3
 11500  13.1  55.6  325  12  6   8.4   4.6 |  13.5  56.3  310  14  7   8.4   4.6
 11000  14.3  57.7  325  11  6   8.1   4.5 |  14.8  58.6  310  12  6   8.6   4.7
 10500  15.5  59.9  330   9  5   4.3   2.4 |  16.1  61.0  310   9  5   4.0   2.2
 10250  15.7  60.3  330   9  5   5.7   3.1 |  16.2  61.2  310   9  5   5.1   2.8
 10000  16.5  61.7  330   8  4  11.7   6.4 |  17.0  62.6  310   8  4  12.0   6.6
  9750  17.3  63.1  330   7  4  10.8   5.9 |  17.8  64.0  310   7  3  11.0   6.1
  9500  18.0  64.4  335   7  3   8.4   4.6 |  18.6  65.5  310   5  3   7.9   4.3
  9250  18.5  65.3  335   6  3   6.3   3.5 |  19.0  66.2  310   4  2   5.8   3.2
  9000  19.1  66.4  335   6  3   8.8   4.9 |  19.6  67.3  305   4  2   9.7   5.3
  8750  19.8  67.6  330   6  3   9.5   5.2 |  20.4  68.7  295   3  1  10.2   5.6
  8500  20.4  68.7  330   5  3   8.3   4.5 |  21.1  70.0  285   2  1   9.8   5.4
  8250  21.0  69.8  325   5  3   7.6   4.2 |  21.8  71.2  275   2  1   9.3   5.1
  8000  21.5  70.7  320   5  3   7.3   4.0 |  22.5  72.5  265   2  1  10.0   5.5
  7750  22.0  71.6  315   5  3   6.4   3.5 |  23.3  73.9  260   1  1  10.5   5.8
  7500  22.5  72.5  305   5  3   5.3   2.9 |  24.1  75.4  260   1  1  10.0   5.5
  7250  22.8  73.0  290   5  3   4.7   2.6 |  24.8  76.6  255   1  1   9.8   5.4
  7000  23.2  73.8  275   5  3   4.6   2.5 |  25.5  77.9  255   1  1  10.1   5.6
  6750  23.5  74.3  260   6  3   2.7   1.5 |  26.3  79.3  255   1  1  10.7   5.8
  6500  23.6  74.5  250   6  3   0.8   0.4 |  27.1  80.8  255   1  1  10.3   5.6
  6250  23.6  74.5  245   6  3   2.4   1.3 |  27.9  82.2  255   1  1  10.7   5.9
  6000  23.6  74.5  235   6  3  -3.1  -1.7 |  28.6  83.5  250   1  1   8.4   4.6
  5750  23.3  73.9  220   6  3   3.3   1.8 |  29.3  84.7  250   1  1  14.6   8.0
  5500  24.5  76.1  220   5  3  30.2  16.6 |  31.1  88.0  255   1  1  31.8  17.4

           06/20/2017 at 1500 MDT          |       06/20/2017 at 1800 MDT
                                           |
K index... +22.0  LI... -0.5               | K index... +22.9  LI... -1.0
CAPE... +277.3  CIN... -37.1               | CAPE... +384.3  CIN... -35.1
                                           |
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 -65.0 -85.0  325  19 10   1.0   0.5 | -65.5 -85.9  305  18 10   2.1   1.1
 45000 -61.9 -79.4  325  29 15   4.5   2.5 | -60.7 -77.3  315  25 13   5.0   2.7
 40000 -54.2 -65.6  320  28 15   7.4   4.1 | -52.8 -63.0  310  24 12   6.9   3.8
 38000 -49.8 -57.6  315  28 14   7.4   4.0 | -48.7 -55.7  305  24 12   6.9   3.8
 36000 -45.3 -49.5  310  27 14   7.7   4.2 | -44.5 -48.1  300  24 12   7.3   4.0
 34000 -40.3 -40.5  305  29 15   8.5   4.6 | -39.6 -39.3  295  27 14   8.2   4.5
 32000 -35.2 -31.4  300  32 17   8.8   4.8 | -34.7 -30.5  295  32 16   8.3   4.6
 30000 -30.1 -22.2  295  34 18   7.5   4.1 | -29.5 -21.1  290  35 18   7.7   4.2
 29000 -27.9 -18.2  290  35 18   7.5   4.1 | -27.2 -17.0  290  36 19   7.7   4.2
 28000 -25.7 -14.3  290  35 18   7.1   3.9 | -25.0 -13.0  290  37 19   6.8   3.7
 27000 -23.6 -10.5  290  35 18   7.1   3.9 | -22.9  -9.2  290  36 18   6.9   3.8
 26000 -21.5  -6.7  290  35 18   7.1   3.9 | -20.9  -5.6  290  35 18   6.9   3.8
 25000 -19.3  -2.7  285  35 18   7.5   4.1 | -18.9  -2.0  290  34 17   7.0   3.8
 24000 -17.1   1.2  285  33 17   7.6   4.2 | -16.8   1.8  290  30 16   7.0   3.9
 23000 -14.8   5.4  285  31 16   7.6   4.2 | -14.7   5.5  290  27 14   7.0   3.9
 22000 -12.5   9.5  285  30 15   7.9   4.3 | -12.6   9.3  290  23 12   8.2   4.5
 21000 -10.1  13.8  285  28 15   8.0   4.4 | -10.0  14.0  290  23 12   8.5   4.7
 20000  -7.7  18.1  290  27 14   8.1   4.4 |  -7.5  18.5  295  22 11   8.5   4.7
 19500  -6.6  20.1  290  27 14   8.3   4.6 |  -6.2  20.8  295  22 11   8.6   4.7
 19000  -5.3  22.5  290  26 13   8.9   4.9 |  -4.9  23.2  295  21 11   8.8   4.8
 18500  -4.0  24.8  290  25 13   8.9   4.9 |  -3.7  25.3  295  21 11   8.8   4.8
 18000  -2.7  27.1  290  24 12   9.2   5.1 |  -2.4  27.7  295  21 11   9.1   5.0
 17500  -1.4  29.5  290  23 12   9.3   5.1 |  -1.0  30.2  295  21 11   9.2   5.0
 17000  -0.0  32.0  290  23 12   9.2   5.1 |   0.3  32.5  295  20 11   9.2   5.0
 16500   1.3  34.3  290  23 12   8.9   4.9 |   1.6  34.9  295  20 10   9.1   5.0
 16000   2.6  36.7  290  23 12   8.9   4.9 |   2.9  37.2  295  19 10   9.1   5.0
 15500   4.5  40.1  290  23 12   9.0   5.0 |   4.9  40.8  295  18  9   9.4   5.1
 15000   5.8  42.4  290  22 11   9.1   5.0 |   6.3  43.3  295  18  9   9.4   5.2
 14500   7.1  44.8  290  21 11   9.2   5.0 |   7.6  45.7  295  16  8   9.2   5.0
 14000   8.5  47.3  290  19 10   9.2   5.0 |   8.9  48.0  295  15  8   9.2   5.0
 13500   9.8  49.6  290  17  9   9.2   5.1 |  10.3  50.5  300  14  7   9.5   5.2
 13000  11.2  52.2  290  14  7   9.3   5.1 |  11.7  53.1  300  12  6   9.5   5.2
 12500  12.5  54.5  290  12  6   8.4   4.6 |  13.1  55.6  300  10  5   9.0   4.9
 12000  13.7  56.7  290   9  5   8.1   4.5 |  14.3  57.7  305   8  4   8.8   4.8
 11500  14.9  58.8  295   6  3   8.2   4.5 |  15.6  60.1  310   5  3   8.7   4.8
 11000  16.1  61.0  295   4  2   8.1   4.4 |  16.9  62.4  315   4  2   8.4   4.6
 10500  17.3  63.1  295   3  1   5.2   2.9 |  18.2  64.8  325   3  2   5.4   3.0
 10250  17.6  63.7  300   2  1   6.8   3.7 |  18.5  65.3  330   3  2   6.2   3.4
 10000  18.4  65.1  300   2  1  11.4   6.2 |  19.2  66.6  340   3  1  10.8   5.9
  9750  19.1  66.4  305   2  1  10.7   5.9 |  19.9  67.8  350   3  1  10.1   5.5
  9500  19.9  67.8  310   2  1   8.9   4.9 |  20.6  69.1  360   3  1   8.5   4.6
  9250  20.5  68.9  310   2  1   8.5   4.7 |  21.2  70.2  360   3  1   8.0   4.4
  9000  21.2  70.2  315   2  1  11.1   6.1 |  21.9  71.4  360   3  2  10.2   5.6
  8750  22.1  71.8  315   2  1  11.1   6.1 |  22.6  72.7  360   3  2  10.0   5.5
  8500  22.9  73.2  315   2  1  10.6   5.8 |  23.4  74.1  360   3  2  10.2   5.6
  8250  23.6  74.5  315   2  1  10.2   5.6 |  24.1  75.4  360   3  2  10.5   5.8
  8000  24.4  75.9  315   2  1   9.8   5.4 |  24.9  76.8  360   3  2   9.9   5.4
  7750  25.1  77.2  315   2  1   9.3   5.1 |  25.6  78.1  360   3  2   9.3   5.1
  7500  25.8  78.4  315   2  1  10.1   5.5 |  26.3  79.3  355   3  2  10.1   5.5
  7250  26.6  79.9  320   2  1  10.6   5.8 |  27.1  80.8  355   4  2  10.8   5.9
  7000  27.4  81.3  320   2  1  10.1   5.5 |  27.9  82.2  355   4  2  10.0   5.5
  6750  28.1  82.6  320   2  1   9.9   5.4 |  28.6  83.5  355   4  2   9.1   5.0
  6500  28.9  84.0  320   2  1  10.5   5.8 |  29.3  84.7  355   4  2   9.9   5.4
  6250  29.7  85.5  320   2  1  11.5   6.3 |  30.1  86.2  350   4  2  10.8   5.9
  6000  30.5  86.9  320   2  1   9.1   5.0 |  30.9  87.6  350   4  2   9.8   5.3
  5750  31.3  88.3  320   2  1  14.4   7.9 |  31.6  88.9  350   4  2  12.1   6.6
  5500  32.9  91.2  320   2  1  30.6  16.8 |  32.8  91.0  350   4  2  19.2  10.6
________________________________________________________________________________

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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