Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171410
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0810 MDT Sunday, August 17, 2014

This forecast is for Sunday, August 17, 2014:

If the trigger temperature of 86.8 F/30.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1240 ft/min (6.3 m/s)
   Maximum height of thermals.................. 18004 ft MSL (12719 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8760 ft MSL (3475 ft AGL)
Thermal soaring outlook for Monday 08/18....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 17805 ft MSL (12520 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 27624 ft MSL (22339 ft AGL)
Wave soaring outlook for Monday 08/18.......... Poor

Remarks...

Sunrise/Sunset.................... 06:13:26 / 19:54:05 MDT
Total possible sunshine........... 13 hr 40 min 40 sec (820 min 40 sec)
Altitude of sun at 13:03:25 MDT... 63.48 degrees

Upper air data from rawinsonde observation taken on 08/17/2014 at 0600 MDT

Freezing level.................. 15697 ft MSL (10412 ft AGL)
Convective condensation level... 19290 ft MSL (14005 ft AGL)
Lifted condensation level....... 18702 ft MSL (13417 ft AGL)
Lifted index.................... -1.6
K index......................... +18.8

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  -65.8 -86.4   290   18    9  -0.6  -0.3   83.1 181.5    29.0      M    M
 45000  -61.7 -79.1   270   31   16   5.2   2.8   65.6 150.0    20.1      M    M
 40000  -52.5 -62.5   275   38   19   6.5   3.6   56.2 133.1    15.3      M    M
 38000  -48.7 -55.7   275   36   18   6.0   3.3   53.2 127.8    13.7      M    M
 36000  -45.0 -49.0   275   33   17   6.1   3.3   50.1 122.1    11.8      M    M
 34000  -41.4 -42.5   275   28   14   6.0   3.3   46.8 116.3     9.8      M    M
 32000  -37.1 -34.8   270   22   11   8.5   4.7   44.9 112.8     8.6      M    M
 30000  -32.1 -25.8   265   22   11   8.3   4.6   43.9 110.9     8.0      M    M
 29000  -29.6 -21.3   270   23   12   8.3   4.6   43.2 109.7     7.6      M    M
 28000  -27.1 -16.8   280   24   12   8.3   4.6   42.6 108.7     7.2      M    M
 27000  -24.4 -11.9   285   24   12   2.7   1.5   41.4 106.6     6.4      M    M
 26000  -23.4 -10.1   280   14    7   5.8   3.2   39.1 102.3     4.6      M    M
 25000  -21.2  -6.2   290   11    6   7.7   4.2   38.2 100.8     3.9      M    M
 24000  -18.8  -1.8   295   11    6   7.8   4.3   37.5  99.5     3.4      M    M
 23000  -16.1   3.0   295   11    6   9.3   5.1   37.2  99.0     3.2      M    M
 22000  -13.4   7.9   300   11    6   9.3   5.1   37.1  98.7     3.1      M    M
 21000  -10.7  12.7   300   11    6   7.4   4.1   36.9  98.4     3.0      M    M
 20000   -8.5  16.7   305   11    6   7.4   4.0   36.1  96.9     2.3      M    M
 19500   -7.4  18.7   310   10    5   7.3   4.0   35.6  96.2     1.9      M    M
 19000   -6.3  20.7   310   10    5   6.8   3.7   35.2  95.4     1.6      M    M
 18500   -5.4  22.3   310    9    5   4.9   2.7   34.6  94.2     1.0      M    M
 18000   -4.6  23.7   305    9    5  -4.5  -2.5   33.9  93.0     0.4      M    M
 17500   -5.5  22.1   305    9    5   9.9   5.4   31.6  89.0    -2.1   1248  6.3
 17000   -4.1  24.6   305    9    4   9.8   5.4   31.6  89.0    -2.1   1189  6.0
 16500   -2.6  27.3   300    8    4   9.8   5.4   31.7  89.0    -2.1   1131  5.7
 16000   -1.2  29.8   300    8    4   9.8   5.3   31.7  89.1    -2.0   1072  5.4
 15500    0.3  32.5   300    8    4   9.7   5.3   31.7  89.0    -2.1   1014  5.1
 15000    1.8  35.2   300    8    4   9.7   5.3   31.7  89.0    -2.1    955  4.9
 14500    3.2  37.8   305    7    4   9.7   5.3   31.6  89.0    -2.1    896  4.6
 14000    4.7  40.5   305    7    4   9.7   5.3   31.7  89.0    -2.1    838  4.3
 13500    6.8  44.2   300    8    4   9.4   5.2   31.6  88.9    -2.2    751  3.8
 13000    8.3  46.9   300    8    4   9.5   5.2   31.6  88.8    -2.2    694  3.5
 12500    9.7  49.5   295    9    4   9.5   5.2   31.5  88.8    -2.3    637  3.2
 12000   11.1  52.0   295    9    5   9.5   5.2   31.5  88.7    -2.3    580  2.9
 11500   12.5  54.5   295    9    5   9.5   5.2   31.4  88.6    -2.4    523  2.7
 11000   13.9  57.0   300    9    5   9.5   5.2   31.4  88.5    -2.5    466  2.4
 10500   15.3  59.5   300    9    5   9.3   5.1   31.3  88.4    -2.5    409  2.1
 10250   16.0  60.8   300    9    5   9.1   5.0   31.3  88.3    -2.6    381  1.9
 10000   16.7  62.1   300   10    5   9.2   5.0   31.2  88.2    -2.6    354  1.8
  9750   17.3  63.1   295   10    5   9.2   5.0   31.2  88.1    -2.7    326  1.7
  9500   18.0  64.4   295   10    5   9.1   5.0   31.1  88.0    -2.8    298  1.5
  9250   18.7  65.7   295   11    6   9.3   5.1   31.1  88.0    -2.8    270  1.4
  9000   19.4  66.9   295   11    6   8.5   4.7   31.1  87.9    -2.8    243  1.2
  8750   19.9  67.8   305   11    6   7.2   3.9   30.9  87.6    -3.0    219  1.1
  8500   20.4  68.7   315   12    6   7.0   3.8   30.7  87.2    -3.3    196  1.0
  8250   20.9  69.6   325   13    7   7.1   3.9   30.5  86.9    -3.5    174  0.9
  8000   21.4  70.5   330   14    7   7.0   3.8   30.3  86.5    -3.7    152  0.8
  7750   21.9  71.4   335   14    7   7.2   4.0   30.1  86.1    -4.0    130  0.7
  7500   22.4  72.3   335   14    7   6.5   3.6   29.9  85.7    -4.2    108  0.5
  7250   22.8  73.0   340   15    8   4.7   2.6   29.5  85.2    -4.6     89  0.4
  7000   23.1  73.6   340   15    8   4.9   2.7   29.1  84.4    -5.0     72  0.4
  6750   23.4  74.1   335   12    6   1.0   0.5   28.7  83.6    -5.5     56  0.3
  6500   23.2  73.8   330   10    5  -2.5  -1.4   27.8  82.1    -6.4     54  0.3
  6250   23.0  73.4   325    7    4  -1.7  -0.9   26.9  80.5    -7.3     51  0.3
  6000   22.9  73.2   305    5    3  -1.4  -0.8   26.1  78.9    -8.2     49  0.2
  5750   22.7  72.9   285    4    2  -3.2  -1.7   25.2  77.4    -9.1     47  0.2
  5500   21.5  70.7   245    3    2 -29.9 -16.4   23.5  74.3   -11.1     75  0.4

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

           08/17/2014 at 0900 MDT          |       08/17/2014 at 1200 MDT
                                           |
K index... +20.8  LI... +0.2               | K index... +20.7  LI... -1.7
CAPE... +114.7  CIN... -78.2               | CAPE... +335.1  CIN... -46.8
                                           |
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 -63.4 -82.1  275  19 10   0.6   0.3 | -63.1 -81.6  270  22 11   0.2   0.1
 45000 -60.3 -76.5  275  28 15   5.5   3.0 | -60.4 -76.7  270  32 16   5.4   2.9
 40000 -52.0 -61.6  275  33 17   5.6   3.1 | -52.3 -62.1  270  32 16   5.7   3.1
 38000 -48.7 -55.7  275  32 16   5.6   3.1 | -48.8 -55.8  275  32 17   5.7   3.1
 36000 -45.3 -49.5  280  31 16   5.6   3.1 | -45.4 -49.7  280  33 17   5.7   3.1
 34000 -41.1 -42.0  280  30 15   6.3   3.5 | -41.1 -42.0  280  32 17   6.4   3.5
 32000 -37.3 -35.1  285  28 15   6.3   3.5 | -37.3 -35.1  280  31 16   6.5   3.6
 30000 -32.7 -26.9  285  26 13   7.7   4.2 | -33.0 -27.4  280  28 15   7.2   4.0
 29000 -30.4 -22.7  280  25 13   7.7   4.3 | -30.8 -23.4  280  27 14   7.2   4.0
 28000 -28.1 -18.6  280  24 12   6.9   3.8 | -28.7 -19.7  280  25 13   7.2   3.9
 27000 -26.1 -15.0  280  22 12   6.8   3.7 | -26.5 -15.7  275  25 13   7.2   3.9
 26000 -24.1 -11.4  280  21 11   6.8   3.7 | -24.4 -11.9  270  24 12   7.2   4.0
 25000 -22.0  -7.6  280  19 10   7.3   4.0 | -22.2  -8.0  265  23 12   7.6   4.2
 24000 -19.5  -3.1  280  17  9   8.4   4.6 | -19.8  -3.6  265  22 11   8.3   4.5
 23000 -17.0   1.4  280  15  7   8.4   4.6 | -17.2   1.0  270  20 10   8.3   4.6
 22000 -14.5   5.9  280  12  6   8.2   4.5 | -14.7   5.5  270  18  9   7.6   4.2
 21000 -12.1  10.2  285  12  6   8.0   4.4 | -12.7   9.1  280  18  9   7.1   3.9
 20000  -9.7  14.5  290  12  6   8.0   4.4 | -10.6  12.9  290  18  9   7.3   4.0
 19500  -8.5  16.7  295  12  6   8.0   4.4 |  -9.6  14.7  295  18  9   7.5   4.1
 19000  -7.5  18.5  295  12  6   6.6   3.6 |  -8.4  16.9  300  18  9   9.1   5.0
 18500  -6.5  20.3  290  13  7   6.8   3.7 |  -7.0  19.4  300  18  9   9.0   4.9
 18000  -5.5  22.1  290  13  7   7.2   3.9 |  -5.7  21.7  300  18  9   8.8   4.8
 17500  -4.4  24.1  290  13  7   7.4   4.0 |  -4.4  24.1  300  17  9   8.8   4.8
 17000  -3.4  25.9  290  13  7   7.6   4.2 |  -3.2  26.2  300  16  8   8.8   4.8
 16500  -1.4  29.5  290  12  6   9.3   5.1 |  -1.2  29.8  295  14  7   9.1   5.0
 16000  -0.1  31.8  295  11  6   9.2   5.1 |   0.2  32.4  295  13  7   9.1   5.0
 15500   1.2  34.2  295  10  5   8.8   4.9 |   1.5  34.7  290  12  6   9.0   4.9
 15000   2.5  36.5  300   9  5   8.9   4.9 |   2.8  37.0  290  11  6   9.0   4.9
 14500   3.8  38.8  300   9  4   9.3   5.1 |   4.1  39.4  290  10  5   9.2   5.0
 14000   5.2  41.4  305   8  4   9.3   5.1 |   5.5  41.9  290   9  5   9.2   5.0
 13500   6.5  43.7  310   8  4   8.9   4.9 |   6.8  44.2  285   8  4   9.1   5.0
 13000   7.8  46.0  310   7  4   8.9   4.9 |   8.2  46.8  290   8  4   9.1   5.0
 12500   9.1  48.4  315   7  4   9.0   5.0 |   9.5  49.1  290   7  4   8.7   4.8
 12000  10.4  50.7  320   7  4   9.1   5.0 |  10.8  51.4  290   6  3   8.6   4.7
 11500  11.8  53.2  325   7  4   9.0   4.9 |  12.1  53.8  295   5  3   8.5   4.7
 11000  13.1  55.6  330   7  4   8.8   4.8 |  13.3  55.9  295   5  2   8.5   4.6
 10500  14.3  57.7  330   8  4   4.2   2.3 |  14.5  58.1  300   4  2   4.3   2.3
 10250  14.5  58.1  330   8  4   6.5   3.6 |  14.8  58.6  300   4  2   6.9   3.8
 10000  15.4  59.7  335   8  4  12.5   6.9 |  15.6  60.1  310   4  2  12.2   6.7
  9750  16.2  61.2  335   8  4  11.1   6.1 |  16.4  61.5  320   4  2  10.9   6.0
  9500  17.0  62.6  335   8  4   8.3   4.5 |  17.2  63.0  330   3  2   8.3   4.5
  9250  17.5  63.5  340   9  4   6.5   3.6 |  17.6  63.7  335   4  2   6.5   3.6
  9000  18.1  64.6  340   9  5   9.4   5.1 |  18.2  64.8  350   4  2   8.4   4.6
  8750  18.8  65.8  340   9  5   9.9   5.4 |  18.8  65.8  360   4  2   8.6   4.7
  8500  19.5  67.1  340   9  5   8.3   4.6 |  19.5  67.1  005   5  2   8.7   4.8
  8250  20.1  68.2  340  10  5   7.6   4.1 |  20.1  68.2  010   5  2   8.9   4.9
  8000  20.6  69.1  340  10  5   7.9   4.3 |  20.7  69.3  015   5  2   8.8   4.8
  7750  21.2  70.2  340  10  5   7.4   4.1 |  21.3  70.3  020   4  2   9.2   5.0
  7500  21.7  71.1  340  10  5   6.5   3.6 |  22.0  71.6  020   4  2  10.1   5.5
  7250  22.2  72.0  340   9  5   6.1   3.3 |  22.7  72.9  020   4  2  10.3   5.7
  7000  22.7  72.9  340   9  5   6.6   3.6 |  23.5  74.3  020   4  2  10.2   5.6
  6750  23.1  73.6  340   9  5   3.5   1.9 |  24.2  75.6  020   4  2  10.2   5.6
  6500  23.1  73.6  335   8  4   0.2   0.1 |  25.0  77.0  020   4  2  10.5   5.8
  6250  23.2  73.8  325   7  4   1.2   0.7 |  25.8  78.4  020   4  2  10.0   5.5
  6000  23.2  73.8  320   7  3  -1.2  -0.7 |  26.6  79.9  020   4  2  11.7   6.4
  5750  22.9  73.2  305   5  2  -0.5  -0.3 |  27.6  81.7  015   4  2  16.8   9.2
  5500  23.0  73.4  280   4  2   7.4   4.1 |  29.0  84.2  015   4  2  19.9  10.9

           08/17/2014 at 1500 MDT          |       08/17/2014 at 1800 MDT
                                           |
K index... +27.4  LI... -2.3               | K index... +24.3  LI... -1.6
CAPE... +386.7  CIN... -18.8               | CAPE... +258.8  CIN... -50.4
                                           |
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 -62.6 -80.7  270  20 10   0.3   0.1 | -62.4 -80.3  285  19 10   0.2   0.1
 45000 -60.1 -76.2  260  33 17   5.0   2.7 | -60.2 -76.4  275  35 18   4.3   2.3
 40000 -52.6 -62.7  265  37 19   5.5   3.0 | -53.6 -64.5  265  44 23   5.6   3.1
 38000 -49.2 -56.6  270  39 20   5.5   3.0 | -50.2 -58.4  265  43 22   5.7   3.1
 36000 -45.9 -50.6  275  40 21   5.4   3.0 | -46.8 -52.2  270  43 22   5.6   3.1
 34000 -41.4 -42.5  275  39 20   7.0   3.8 | -42.0 -43.6  270  39 20   7.4   4.1
 32000 -37.2 -35.0  275  38 20   7.2   3.9 | -37.5 -35.5  270  36 19   7.8   4.3
 30000 -32.8 -27.0  280  34 18   7.4   4.1 | -32.4 -26.3  270  33 17   8.7   4.8
 29000 -30.5 -22.9  280  32 16   7.4   4.1 | -29.8 -21.6  275  32 17   8.7   4.8
 28000 -28.3 -18.9  280  30 15   7.4   4.1 | -27.3 -17.1  275  31 16   7.2   3.9
 27000 -26.1 -15.0  280  29 15   7.4   4.1 | -25.2 -13.4  275  31 16   7.0   3.8
 26000 -23.9 -11.0  280  28 14   7.4   4.1 | -23.1  -9.6  280  31 16   7.0   3.8
 25000 -21.7  -7.1  285  27 14   7.5   4.1 | -21.1  -6.0  280  31 16   7.1   3.9
 24000 -19.4  -2.9  285  26 13   7.8   4.3 | -18.9  -2.0  285  30 15   7.2   4.0
 23000 -17.1   1.2  285  26 13   7.8   4.3 | -16.7   1.9  285  29 15   7.3   4.0
 22000 -14.8   5.4  290  25 13   7.3   4.0 | -14.6   5.7  290  28 14   7.1   3.9
 21000 -12.7   9.1  290  24 12   7.0   3.8 | -12.5   9.5  295  27 14   7.0   3.8
 20000 -10.7  12.7  290  23 12   7.1   3.9 | -10.5  13.1  295  27 14   7.0   3.8
 19500  -9.7  14.5  295  22 11   7.3   4.0 |  -9.4  15.1  295  27 14   7.0   3.8
 19000  -8.5  16.7  295  22 11   9.8   5.4 |  -8.2  17.2  295  26 13   9.8   5.4
 18500  -7.1  19.2  295  21 11   9.6   5.3 |  -6.8  19.8  300  24 12   9.5   5.2
 18000  -5.7  21.7  300  21 11   9.3   5.1 |  -5.4  22.3  300  23 12   9.7   5.3
 17500  -4.4  24.1  300  19 10   9.1   5.0 |  -3.9  25.0  300  20 10   9.9   5.4
 17000  -3.1  26.4  300  17  9   9.1   5.0 |  -2.5  27.5  300  18  9   9.9   5.4
 16500  -1.1  30.0  300  14  7   8.8   4.9 |  -0.5  31.1  300  13  7   8.9   4.9
 16000   0.2  32.4  295  12  6   8.7   4.8 |   0.8  33.4  300  10  5   8.8   4.8
 15500   1.4  34.5  295   9  5   8.2   4.5 |   2.0  35.6  295   6  3   8.3   4.5
 15000   2.7  36.9  285   7  4   8.2   4.5 |   3.2  37.8  280   3  2   8.3   4.6
 14500   4.0  39.2  275   6  3   8.6   4.7 |   4.4  39.9  235   2  1   8.4   4.6
 14000   5.3  41.5  265   4  2   8.6   4.7 |   5.6  42.1  205   3  1   8.4   4.6
 13500   6.6  43.9  250   3  2   9.3   5.1 |   6.9  44.4  190   3  2   8.4   4.6
 13000   8.0  46.4  240   2  1   9.4   5.1 |   8.2  46.8  190   4  2   8.4   4.6
 12500   9.4  48.9  225   1  1   9.3   5.1 |   9.5  49.1  190   4  2   9.0   4.9
 12000  10.7  51.3  230   1  0   9.3   5.1 |  10.9  51.6  190   4  2   9.3   5.1
 11500  12.1  53.8  000   0  0   9.2   5.0 |  12.3  54.1  195   4  2   9.2   5.1
 11000  13.4  56.1  010   1  0   9.1   5.0 |  13.6  56.5  200   4  2   8.8   4.8
 10500  14.7  58.5  005   1  1   4.6   2.5 |  15.0  59.0  210   4  2   4.4   2.4
 10250  14.9  58.8  010   1  1   7.5   4.1 |  15.2  59.4  210   4  2   6.0   3.3
 10000  15.8  60.4  005   1  1  13.5   7.4 |  16.0  60.8  215   3  2  12.9   7.1
  9750  16.7  62.1  360   1  1  12.2   6.7 |  16.9  62.4  220   3  2  11.7   6.4
  9500  17.6  63.7  360   1  1   9.3   5.1 |  17.7  63.9  230   3  2   9.5   5.2
  9250  18.2  64.8  355   1  1   7.9   4.4 |  18.3  64.9  235   4  2   7.8   4.3
  9000  18.9  66.0  355   2  1  10.9   6.0 |  19.0  66.2  240   4  2  10.0   5.5
  8750  19.7  67.5  350   2  1  11.1   6.1 |  19.7  67.5  245   4  2  10.2   5.6
  8500  20.5  68.9  345   2  1  10.2   5.6 |  20.5  68.9  250   4  2   9.9   5.4
  8250  21.3  70.3  345   2  1   9.5   5.2 |  21.2  70.2  255   4  2   9.8   5.4
  8000  22.0  71.6  345   2  1  10.0   5.5 |  21.9  71.4  255   4  2   9.2   5.0
  7750  22.7  72.9  340   2  1  10.2   5.6 |  22.5  72.5  255   4  2   8.7   4.8
  7500  23.5  74.3  340   2  1   9.9   5.4 |  23.2  73.8  260   5  2   9.7   5.3
  7250  24.2  75.6  340   2  1   9.7   5.3 |  23.9  75.0  260   5  2  10.2   5.6
  7000  25.0  77.0  335   2  1  10.1   5.5 |  24.7  76.5  260   5  2   9.7   5.3
  6750  25.8  78.4  335   2  1  10.9   6.0 |  25.4  77.7  260   5  2   9.7   5.3
  6500  26.6  79.9  335   2  1  10.8   6.0 |  26.1  79.0  260   5  3  10.3   5.6
  6250  27.4  81.3  335   2  1  11.3   6.2 |  26.9  80.4  260   5  3  11.1   6.1
  6000  28.2  82.8  335   2  1   9.4   5.2 |  27.7  81.9  260   5  3   8.7   4.8
  5750  29.0  84.2  335   2  1  14.1   7.7 |  28.3  82.9  265   5  3  10.0   5.5
  5500  30.5  86.9  335   2  1  27.4  15.0 |  29.3  84.7  265   5  3  19.1  10.5
________________________________________________________________________________

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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