Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211309
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0709 MDT Friday, August 21, 2015

This forecast is for Friday, August 21, 2015:

If the trigger temperature of 83.1 F/28.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1396 ft/min (7.1 m/s)
   Maximum height of thermals.................. 19645 ft MSL (14360 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1115 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................. 17064 ft MSL (11778 ft AGL)
Thermal soaring outlook for Saturday 08/22..... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Becoming fair by 1200 MDT.
Height of stable layer (12-18K ft MSL)......... 17088 ft MSL (11803 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17580 ft MSL (12295 ft AGL)
Wave soaring outlook for Saturday 08/22........ Fair

Remarks...

Sunrise/Sunset.................... 06:16:58 / 19:48:52 MDT
Total possible sunshine........... 13 hr 31 min 53 sec (811 min 53 sec)
Altitude of sun at 13:02:32 MDT... 62.25 degrees

Upper air data from rawinsonde observation taken on 08/21/2015 at 0600 MDT

Freezing level.................. 14941 ft MSL (9656 ft AGL)
Convective condensation level... 18251 ft MSL (12966 ft AGL)
Lifted condensation level....... 19128 ft MSL (13843 ft AGL)
Lifted index.................... -1.8
K index......................... +17.6

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  -59.3 -74.7   295   31   16   1.7   0.9   95.3 203.5    36.3      M    M
 45000  -55.6 -68.1   295   37   19   1.7   1.0   77.0 170.7    27.5      M    M
 40000  -53.6 -64.5   290   42   22   1.0   0.6   56.3 133.4    15.7      M    M
 38000  -53.2 -63.8   285   33   17   4.8   2.6   48.2 118.7    10.6      M    M
 36000  -49.0 -56.2   275   25   13   8.7   4.8   45.8 114.4     9.1      M    M
 34000  -44.2 -47.6   270   19   10   7.9   4.3   44.4 111.9     8.4      M    M
 32000  -40.7 -41.3   265   12    6   8.1   4.4   41.1 106.0     6.2      M    M
 30000  -36.0 -32.8   275   19   10   7.9   4.3   39.7 103.4     5.2      M    M
 29000  -33.0 -27.4   280   17    9   7.5   4.1   38.7 101.7     4.6      M    M
 28000  -31.5 -24.7   285   15    8   4.4   2.4   37.0  98.7     3.3      M    M
 27000  -29.0 -20.2   295   14    7   9.2   5.1   36.4  97.5     2.8      M    M
 26000  -26.2 -15.2   300   13    7   9.2   5.1   36.2  97.1     2.7      M    M
 25000  -23.4 -10.1   310   12    6   9.8   5.4   36.1  97.0     2.7      M    M
 24000  -20.6  -5.1   295   12    6   9.2   5.0   35.9  96.6     2.5      M    M
 23000  -17.9  -0.2   275   13    7   9.3   5.1   35.7  96.3     2.4      M    M
 22000  -15.6   3.9   260   16    8   7.2   4.0   35.0  95.0     1.8      M    M
 21000  -13.5   7.7   290   17    9   7.2   4.0   34.1  93.4     1.1      M    M
 20000  -11.3  11.7   290   16    8   7.2   4.0   33.2  91.8     0.3      M    M
 19500  -10.2  13.6   295   16    8   7.3   4.0   32.7  90.9    -0.1   1386  7.0
 19000   -9.1  15.6   290   17    9   8.8   4.8   32.3  90.2    -0.4   1338  6.8
 18500   -8.3  17.1   300   15    8   1.9   1.1   31.6  88.9    -1.1   1299  6.6
 18000   -7.6  18.3   315   13    7   8.2   4.5   30.9  87.5    -1.9   1264  6.4
 17500   -6.4  20.5   305   16    8   8.5   4.7   30.6  87.0    -2.2   1214  6.2
 17000   -5.7  21.7   295   20   10   1.9   1.1   29.8  85.7    -2.9   1177  6.0
 16500   -4.9  23.2   295   22   11   9.7   5.3   29.2  84.5    -3.6   1139  5.8
 16000   -3.5  25.7   295   23   12   9.9   5.4   29.2  84.6    -3.6   1081  5.5
 15500   -2.0  28.4   295   23   12   9.9   5.4   29.2  84.6    -3.6   1022  5.2
 15000   -0.5  31.1   295   24   12   9.9   5.4   29.3  84.7    -3.6    963  4.9
 14500    1.7  35.1   290   22   11   9.9   5.4   29.3  84.7    -3.7    875  4.4
 14000    3.1  37.6   285   21   11   9.9   5.4   29.3  84.7    -3.7    816  4.1
 13500    4.6  40.3   280   20   10   9.8   5.4   29.3  84.7    -3.7    757  3.8
 13000    6.0  42.8   280   19   10   9.7   5.3   29.3  84.7    -3.8    699  3.6
 12500    7.5  45.5   275   18    9   9.7   5.3   29.3  84.7    -3.8    641  3.3
 12000    8.9  48.0   275   17    9   9.7   5.3   29.3  84.7    -3.8    583  3.0
 11500   10.4  50.7   270   17    9   9.7   5.3   29.2  84.6    -3.9    526  2.7
 11000   11.8  53.2   270   16    8   9.7   5.3   29.2  84.6    -3.9    468  2.4
 10500   13.2  55.8   265   16    8   9.7   5.3   29.2  84.6    -4.0    410  2.1
 10250   13.9  57.0   265   16    8   9.3   5.1   29.2  84.6    -4.0    381  1.9
 10000   14.6  58.3   270   16    8   9.0   4.9   29.2  84.5    -4.0    354  1.8
  9750   15.3  59.5   265   14    7   9.1   5.0   29.1  84.4    -4.1    326  1.7
  9500   16.2  61.2   265   12    6   9.1   5.0   29.1  84.3    -4.2    299  1.5
  9250   16.6  61.9   260   10    5   9.1   5.0   29.0  84.3    -4.2    271  1.4
  9000   17.3  63.1   255    9    5   9.1   5.0   29.0  84.2    -4.3    244  1.2
  8750   18.0  64.4   260    9    5   9.1   5.0   28.9  84.1    -4.4    216  1.1
  8500   18.6  65.5   260    9    5   9.1   5.0   28.9  84.0    -4.4    189  1.0
  8250   19.3  66.7   265    9    5   9.1   5.0   28.8  83.9    -4.5    161  0.8
  8000   20.0  68.0   265    9    5   9.0   5.0   28.8  83.8    -4.6    134  0.7
  7750   20.7  69.3   260   10    5   9.2   5.1   28.7  83.7    -4.6    106  0.5
  7500   21.3  70.3   260   10    5   8.5   4.6   28.7  83.6    -4.7     79  0.4
  7250   21.7  71.1   255   11    6   0.6   0.3   28.3  83.0    -5.1     59  0.3
  7000   21.4  70.5   255   12    6  -4.5  -2.4   27.3  81.2    -6.1     61  0.3
  6750   21.1  70.0   245   12    6  -3.0  -1.6   26.3  79.4    -7.1     62  0.3
  6500   20.8  69.4   235   13    7  -3.7  -2.0   25.3  77.6    -8.2     63  0.3
  6250   20.6  69.1   230   14    7  -2.2  -1.2   24.3  75.8    -9.2     65  0.3
  6000   20.3  68.5   220   15    8  -7.6  -4.1   23.4  74.1   -10.2     66  0.3
  5750   19.3  66.7   220   12    6 -14.1  -7.7   21.7  71.1   -12.0     88  0.4
  5500   18.1  64.6   225    8    4 -16.8  -9.2   19.9  67.8   -13.9    115  0.6

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

           08/21/2015 at 0900 MDT          |       08/21/2015 at 1200 MDT
                                           |
K index... -0.5  LI... +2.7                | K index... +7.3  LI... +2.1
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... M
                                           |
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 -59.7 -75.5  290  23 12   2.7   1.5 | -59.7 -75.5  285  23 12   2.1   1.1
 45000 -55.7 -68.3  300  27 14   2.4   1.3 | -56.4 -69.5  295  28 14   2.6   1.4
 40000 -51.9 -61.4  300  29 15   2.8   1.5 | -52.3 -62.1  305  26 13   3.1   1.7
 38000 -50.2 -58.4  300  26 14   2.8   1.6 | -50.5 -58.9  310  25 13   3.1   1.7
 36000 -48.5 -55.3  295  24 12   2.9   1.6 | -48.7 -55.7  310  23 12   3.1   1.7
 34000 -44.9 -48.8  295  22 11   7.6   4.2 | -44.8 -48.6  310  23 12   8.0   4.4
 32000 -40.3 -40.5  295  20 11   7.6   4.2 | -40.0 -40.0  310  23 12   8.0   4.4
 30000 -35.5 -31.9  295  19 10   7.0   3.9 | -34.9 -30.8  305  22 11   7.3   4.0
 29000 -33.4 -28.1  290  19 10   7.0   3.9 | -32.8 -27.0  300  22 11   7.3   4.0
 28000 -31.2 -24.2  290  18  9   7.3   4.0 | -30.6 -23.1  300  22 11   7.5   4.1
 27000 -28.8 -19.8  290  18  9   8.1   4.5 | -28.2 -18.8  295  22 11   7.9   4.3
 26000 -26.4 -15.5  285  18  9   8.1   4.5 | -25.9 -14.6  295  21 11   7.9   4.3
 25000 -24.0 -11.2  285  17  9   8.1   4.4 | -23.5 -10.3  290  21 11   7.8   4.3
 24000 -21.5  -6.7  285  17  9   8.5   4.6 | -21.0  -5.8  285  21 11   8.5   4.7
 23000 -18.9  -2.0  290  17  9   8.5   4.6 | -18.5  -1.3  285  21 11   8.5   4.7
 22000 -16.4   2.5  290  17  9   8.5   4.7 | -15.9   3.4  280  21 11   8.5   4.7
 21000 -13.9   7.0  290  18  9   8.2   4.5 | -13.5   7.7  285  21 11   7.9   4.3
 20000 -11.5  11.3  290  19 10   8.2   4.5 | -11.1  12.0  285  21 11   7.9   4.3
 19500 -10.2  13.6  295  19 10   8.2   4.5 | -10.0  14.0  285  21 11   8.0   4.4
 19000  -9.0  15.8  295  20 10   7.6   4.2 |  -8.8  16.2  285  21 11   7.2   3.9
 18500  -7.9  17.8  295  20 10   7.4   4.1 |  -7.8  18.0  290  20 11   7.0   3.8
 18000  -6.8  19.8  295  21 11   7.4   4.1 |  -6.8  19.8  290  20 10   7.0   3.9
 17500  -5.7  21.7  295  21 11   7.7   4.2 |  -5.7  21.7  295  20 10   7.8   4.3
 17000  -4.6  23.7  300  21 11   7.7   4.2 |  -4.5  23.9  295  20 10   7.7   4.2
 16500  -3.4  25.9  300  20 11   8.1   4.5 |  -3.4  25.9  300  20 11   8.4   4.6
 16000  -2.2  28.0  300  20 10   8.3   4.5 |  -2.1  28.2  300  21 11   8.6   4.7
 15500  -0.3  31.5  300  20 10   8.2   4.5 |  -0.2  31.6  300  22 11   8.8   4.8
 15000   0.9  33.6  300  20 10   8.2   4.5 |   1.1  34.0  300  22 11   8.8   4.8
 14500   2.1  35.8  300  20 10   8.5   4.7 |   2.4  36.3  300  22 11   9.1   5.0
 14000   3.3  37.9  300  20 10   8.7   4.8 |   3.8  38.8  300  22 11   9.3   5.1
 13500   4.6  40.3  295  19 10   8.8   4.8 |   5.2  41.4  300  21 11   9.3   5.1
 13000   5.9  42.6  295  19 10   9.0   4.9 |   6.5  43.7  300  21 11   9.2   5.0
 12500   7.2  45.0  290  18  9   9.1   5.0 |   7.9  46.2  305  20 10   9.2   5.0
 12000   8.6  47.5  290  18  9   9.5   5.2 |   9.2  48.6  305  19 10   9.1   5.0
 11500  10.0  50.0  285  18 10   9.5   5.2 |  10.5  50.9  305  18  9   9.1   5.0
 11000  11.4  52.5  285  19 10   8.6   4.7 |  11.7  53.1  305  16  8   7.6   4.2
 10500  12.7  54.9  285  19 10   5.7   3.1 |  12.8  55.0  305  15  8  10.8   5.9
 10250  13.0  55.4  285  19 10   6.4   3.5 |  13.8  56.8  305  13  7  11.5   6.3
 10000  13.7  56.7  285  19 10  11.0   6.0 |  14.4  57.9  300  13  6   7.9   4.3
  9750  14.4  57.9  285  19 10   9.8   5.4 |  15.1  59.2  300  12  6   8.9   4.9
  9500  15.2  59.4  285  18  9   9.9   5.4 |  15.7  60.3  300  11  6   8.4   4.6
  9250  15.8  60.4  285  18  9   8.3   4.5 |  16.3  61.3  295  10  5   8.1   4.4
  9000  16.4  61.5  285  18  9   8.3   4.5 |  16.9  62.4  290   9  5   8.8   4.8
  8750  17.1  62.8  285  17  9   9.1   5.0 |  17.6  63.7  280   9  4   9.3   5.1
  8500  17.7  63.9  285  17  9   8.9   4.9 |  18.3  64.9  275   8  4   9.3   5.1
  8250  18.4  65.1  290  17  9   9.1   5.0 |  19.0  66.2  270   8  4  10.1   5.6
  8000  19.0  66.2  290  16  8   8.4   4.6 |  19.7  67.5  265   8  4  10.3   5.6
  7750  19.6  67.3  290  16  8   7.5   4.1 |  20.5  68.9  265   8  4  10.1   5.5
  7500  20.2  68.4  290  15  8   7.8   4.3 |  21.2  70.2  265   7  4  10.0   5.5
  7250  20.8  69.4  290  16  8   8.1   4.4 |  22.0  71.6  265   7  4   9.7   5.3
  7000  21.3  70.3  290  17  9   7.9   4.4 |  22.7  72.9  265   7  4   9.8   5.4
  6750  22.0  71.6  290  18  9   9.4   5.2 |  23.5  74.3  265   7  4  10.1   5.6
  6500  22.6  72.7  285  18  9   4.7   2.6 |  24.2  75.6  260   7  4  10.6   5.8
  6250  22.6  72.7  285  16  8   0.2   0.1 |  25.0  77.0  260   7  4  11.1   6.1
  6000  22.6  72.7  280  15  7   1.0   0.5 |  25.8  78.4  260   7  4  10.4   5.7
  5750  22.4  72.3  275  13  7  -5.2  -2.8 |  26.6  79.9  260   7  3  12.2   6.7
  5500  21.7  71.1  260   9  5  -7.2  -3.9 |  27.8  82.0  260   6  3  20.3  11.1

           08/21/2015 at 1500 MDT          |       08/21/2015 at 1800 MDT
                                           |
K index... +14.9  LI... +1.7               | K index... +21.9  LI... -0.0
CAPE... 0.0  CIN... -3.4                   | CAPE... +78.9  CIN... -15.4
                                           |
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 -60.6 -77.1  280  25 13   2.1   1.2 | -61.4 -78.5  285  31 16   1.8   1.0
 45000 -57.0 -70.6  300  33 17   2.8   1.5 | -58.0 -72.4  300  42 22   3.0   1.7
 40000 -52.8 -63.0  310  32 16   4.1   2.3 | -53.3 -63.9  305  39 20   4.5   2.5
 38000 -50.4 -58.7  315  30 15   4.0   2.2 | -50.7 -59.3  310  37 19   4.4   2.4
 36000 -48.1 -54.6  320  28 14   4.0   2.2 | -48.1 -54.6  315  36 19   4.5   2.5
 34000 -44.2 -47.6  320  27 14   7.5   4.1 | -43.8 -46.8  315  33 17   8.2   4.5
 32000 -39.7 -39.5  320  26 13   7.5   4.1 | -38.8 -37.8  315  30 15   8.2   4.5
 30000 -34.7 -30.5  310  25 13   7.5   4.1 | -33.5 -28.3  310  28 14   7.7   4.2
 29000 -32.4 -26.3  305  24 12   7.5   4.1 | -31.3 -24.3  305  27 14   7.7   4.2
 28000 -30.2 -22.4  300  24 12   7.6   4.2 | -29.0 -20.2  300  27 14   7.6   4.2
 27000 -27.8 -18.0  295  23 12   7.8   4.3 | -26.7 -16.1  300  25 13   7.5   4.1
 26000 -25.5 -13.9  295  23 12   7.8   4.3 | -24.5 -12.1  300  24 12   7.5   4.1
 25000 -23.2  -9.8  290  22 11   7.7   4.2 | -22.3  -8.1  295  23 12   7.4   4.1
 24000 -20.7  -5.3  295  22 11   8.7   4.8 | -19.9  -3.8  295  22 12   8.3   4.5
 23000 -18.1  -0.6  295  22 12   8.7   4.8 | -17.4   0.7  295  23 12   8.3   4.5
 22000 -15.5   4.1  300  23 12   8.7   4.8 | -14.9   5.2  295  23 12   8.2   4.5
 21000 -13.0   8.6  300  24 13   8.0   4.4 | -12.7   9.1  295  24 12   7.4   4.1
 20000 -10.7  12.7  300  26 14   8.0   4.4 | -10.6  12.9  290  26 13   7.5   4.1
 19500  -9.5  14.9  300  27 14   8.0   4.4 |  -9.5  14.9  290  27 14   7.5   4.1
 19000  -8.3  17.1  300  29 15   7.9   4.3 |  -8.4  16.9  290  27 14   8.9   4.9
 18500  -7.1  19.2  300  30 16   8.0   4.4 |  -7.0  19.4  290  27 14   9.1   5.0
 18000  -6.0  21.2  300  32 17   8.1   4.4 |  -5.7  21.7  290  27 14   9.1   5.0
 17500  -4.8  23.4  300  32 17   8.4   4.6 |  -4.4  24.1  285  26 13   9.2   5.1
 17000  -3.6  25.5  300  32 17   8.5   4.6 |  -3.1  26.4  285  25 13   9.2   5.1
 16500  -2.3  27.9  295  32 16   8.8   4.8 |  -1.7  28.9  285  24 13   9.3   5.1
 16000  -0.4  31.3  295  30 15   8.9   4.9 |  -0.4  31.3  280  24 12   9.4   5.1
 15500   0.9  33.6  295  29 15   9.1   5.0 |   1.7  35.1  280  22 11   9.6   5.3
 15000   2.2  36.0  295  27 14   9.2   5.0 |   3.2  37.8  280  21 11   9.6   5.3
 14500   3.6  38.5  290  25 13   9.1   5.0 |   4.6  40.3  280  20 10   9.6   5.3
 14000   4.9  40.8  290  24 12   9.1   5.0 |   6.0  42.8  280  20 10   9.6   5.2
 13500   6.3  43.3  290  23 12   9.2   5.0 |   7.5  45.5  280  19 10   9.4   5.2
 13000   7.7  45.9  290  22 11   9.4   5.2 |   8.8  47.8  280  17  9   9.2   5.1
 12500   9.1  48.4  290  20 10   9.3   5.1 |  10.2  50.4  280  16  8   9.2   5.0
 12000  10.4  50.7  290  18  9   8.8   4.8 |  11.5  52.7  280  15  8   8.7   4.8
 11500  11.8  53.2  290  16  8   8.8   4.8 |  12.9  55.2  280  13  7   8.7   4.8
 11000  12.9  55.2  290  13  7   7.2   3.9 |  14.1  57.4  275  11  6   7.9   4.3
 10500  14.0  57.2  280  10  5   9.9   5.4 |  15.2  59.4  270  10  5  10.6   5.8
 10250  14.9  58.8  275   8  4  11.3   6.2 |  16.2  61.2  265   9  4  10.8   5.9
 10000  15.6  60.1  270   7  4   8.8   4.8 |  16.8  62.2  255   8  4   7.5   4.1
  9750  16.3  61.3  265   7  3   9.5   5.2 |  17.4  63.3  245   8  4   8.4   4.6
  9500  17.0  62.6  255   6  3   9.1   5.0 |  18.0  64.4  235   7  4   8.0   4.4
  9250  17.6  63.7  250   6  3   9.1   5.0 |  18.6  65.5  225   8  4   7.5   4.1
  9000  18.3  64.9  245   6  3   9.9   5.4 |  19.2  66.6  220   8  4   8.0   4.4
  8750  19.1  66.4  245   6  3  10.3   5.7 |  19.8  67.6  215   8  4   8.6   4.7
  8500  19.8  67.6  245   6  3  10.2   5.6 |  20.4  68.7  215   8  4   8.5   4.7
  8250  20.6  69.1  245   6  3  10.4   5.7 |  21.1  70.0  210   8  4  10.0   5.5
  8000  21.4  70.5  240   5  3  10.0   5.5 |  21.9  71.4  210   8  4  10.2   5.6
  7750  22.1  71.8  240   5  3   9.4   5.2 |  22.6  72.7  210   7  4   9.4   5.2
  7500  22.8  73.0  240   5  3   9.8   5.4 |  23.3  73.9  210   7  4   9.8   5.4
  7250  23.6  74.5  240   5  3  10.4   5.7 |  24.1  75.4  210   7  4  10.5   5.8
  7000  24.3  75.7  240   5  3  10.3   5.6 |  24.8  76.6  210   7  4  10.4   5.7
  6750  25.1  77.2  240   5  3   9.4   5.2 |  25.6  78.1  210   7  4   9.2   5.1
  6500  25.8  78.4  240   5  3   9.9   5.5 |  26.3  79.3  210   7  4   9.6   5.3
  6250  26.6  79.9  235   5  3  11.0   6.0 |  27.0  80.6  210   7  4  10.7   5.8
  6000  27.4  81.3  235   5  3  10.5   5.8 |  27.8  82.0  215   7  4  10.6   5.8
  5750  28.2  82.8  235   5  3  11.9   6.5 |  28.6  83.5  215   7  3   9.6   5.3
  5500  29.3  84.7  235   5  3  19.8  10.8 |  29.3  84.7  215   6  3  10.6   5.8
________________________________________________________________________________

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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