Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171331
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0731 MDT Sunday, May 17, 2015

This forecast is for Sunday, May 17, 2015:

If the trigger temperature of 60.1 F/15.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 754 ft/min (3.8 m/s)
   Maximum height of thermals.................. 14188 ft MSL (8903 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10587 ft MSL (5301 ft AGL)
Thermal soaring outlook for Monday 05/18....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14613 ft MSL (9328 ft AGL)
Wave soaring outlook for Monday 05/18.......... Poor

Remarks...

Sunrise/Sunset.................... 05:43:24 / 20:08:10 MDT
Total possible sunshine........... 14 hr 24 min 46 sec (864 min 46 sec)
Altitude of sun at 12:55:59 MDT... 69.60 degrees

Upper air data from rawinsonde observation taken on 05/17/2015 at 0600 MDT

Freezing level.................. 10756 ft MSL (5471 ft AGL)
Convective condensation level... 15607 ft MSL (10322 ft AGL)
Lifted condensation level....... 15406 ft MSL (10121 ft AGL)
Lifted index.................... -0.4
K index......................... +16.4

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  -55.0 -67.0   235   29   15   2.5   1.4  106.5 223.7    50.0      M    M
 45000  -51.9 -61.4   215   23   12   6.9   3.8   87.1 188.7    41.5      M    M
 40000  -49.8 -57.6   255   32   16   8.3   4.5   66.1 151.0    30.7      M    M
 38000  -49.2 -56.6   270   30   15   0.2   0.1   58.3 137.0    26.3      M    M
 36000  -46.6 -51.9   275   31   16   1.5   0.8   53.7 128.7    23.8      M    M
 34000  -49.5 -57.1   260   56   29 -24.6 -13.5   41.3 106.3    15.5      M    M
 32000  -52.0 -61.6   270   36   19   6.9   3.8   29.6  85.3     7.4      M    M
 30000  -48.1 -54.6   285   40   21   7.6   4.2   27.0  80.6     5.7      M    M
 29000  -45.3 -49.5   280   39   20   9.3   5.1   26.6  79.9     5.4      M    M
 28000  -42.6 -44.7   280   38   19   9.3   5.1   26.3  79.4     5.3      M    M
 27000  -39.1 -38.4   275   36   19   9.3   5.1   26.1  79.0     5.2      M    M
 26000  -36.3 -33.3   270   36   18   9.3   5.1   26.1  79.0     5.3      M    M
 25000  -33.5 -28.3   265   35   18   9.2   5.1   26.2  79.1     5.3      M    M
 24000  -31.0 -23.8   265   35   18   8.4   4.6   25.7  78.3     5.0      M    M
 23000  -28.4 -19.1   265   34   18   8.8   4.9   25.3  77.5     4.7      M    M
 22000  -25.8 -14.4   265   33   17   8.9   4.9   25.0  77.0     4.5      M    M
 21000  -23.3  -9.9   275   31   16   6.5   3.6   24.5  76.0     4.1      M    M
 20000  -21.3  -6.3   290   31   16   6.5   3.5   23.4  74.0     3.2      M    M
 19500  -20.2  -4.4   295   30   15   8.8   4.8   22.9  73.3     2.8      M    M
 19000  -18.9  -2.0   295   28   15   9.2   5.0   22.8  73.0     2.7      M    M
 18500  -17.9  -0.2   300   27   14   3.2   1.8   22.2  72.0     2.2      M    M
 18000  -17.7   0.1   310   25   13   5.2   2.9   20.9  69.7     1.0      M    M
 17500  -16.3   2.7   310   25   13   9.2   5.1   20.8  69.4     0.9      M    M
 17000  -15.0   5.0   310   25   13   9.3   5.1   20.7  69.2     0.8      M    M
 16500  -13.6   7.5   310   25   13   9.3   5.1   20.6  69.1     0.8      M    M
 16000  -12.2  10.0   310   25   13   9.6   5.3   20.6  69.1     0.8      M    M
 15500  -10.7  12.7   305   27   14   9.6   5.2   20.6  69.0     0.7      M    M
 15000   -9.3  15.3   305   29   15   9.4   5.2   20.5  68.9     0.7      M    M
 14500   -7.9  17.8   300   32   16   7.3   4.0   20.5  68.9     0.7      M    M
 14000   -7.2  19.0   300   34   18   5.5   3.0   19.7  67.5    -0.1    749  3.8
 13500   -5.9  21.4   295   37   19   5.9   3.3   18.8  65.8    -1.0    688  3.5
 13000   -5.0  23.0   290   37   19   6.0   3.3   18.2  64.7    -1.6    647  3.3
 12500   -4.2  24.4   290   30   15   6.3   3.4   17.6  63.6    -2.2    606  3.1
 12000   -3.0  26.6   290   23   12   8.7   4.8   17.3  63.1    -2.5    557  2.8
 11500   -1.7  28.9   290   20   10   8.6   4.7   17.1  62.7    -2.7    504  2.6
 11000   -0.5  31.1   295   17    9   8.6   4.7   16.9  62.4    -2.9    451  2.3
 10500    0.8  33.4   285   14    7   8.5   4.7   16.7  62.1    -3.1    398  2.0
 10250    1.5  34.7   275   13    7   8.7   4.8   16.6  61.9    -3.2    372  1.9
 10000    2.1  35.8   275   11    6   8.0   4.4   16.5  61.7    -3.3    345  1.8
  9750    2.7  36.9   275   11    6   7.4   4.1   16.3  61.4    -3.4    321  1.6
  9500    3.2  37.8   275   11    6   7.9   4.3   16.2  61.1    -3.6    296  1.5
  9250    3.8  38.8   280   11    6   7.9   4.3   16.0  60.9    -3.7    271  1.4
  9000    4.4  39.9   280   11    6   7.9   4.3   15.9  60.6    -3.9    246  1.3
  8750    5.0  41.0   270   10    5   7.9   4.3   15.8  60.4    -4.0    221  1.1
  8500    5.6  42.1   260   10    5   7.9   4.3   15.6  60.1    -4.2    196  1.0
  8250    6.2  43.2   250   10    5   7.9   4.3   15.5  59.9    -4.3    172  0.9
  8000    6.8  44.2   240   10    5   7.9   4.3   15.4  59.6    -4.5    147  0.7
  7750    7.3  45.1   235   12    6   7.9   4.3   15.2  59.4    -4.6    122  0.6
  7500    7.9  46.2   235   13    7   7.9   4.3   15.1  59.1    -4.8     97  0.5
  7250    8.5  47.3   230   15    8   8.0   4.4   14.9  58.8    -5.0     72  0.4
  7000    9.1  48.4   230   17    9   7.8   4.3   14.8  58.6    -5.1     47  0.2
  6750    9.7  49.5   230   14    7   8.5   4.7   14.6  58.3    -5.3     22  0.1
  6500   10.3  50.5   235   12    6   5.7   3.1   14.5  58.1    -5.4      M    M
  6250   10.4  50.7   235    9    5   0.5   0.3   14.0  57.1    -6.0      M    M
  6000   10.5  50.9   240    6    3   4.1   2.2   13.3  56.0    -6.7      M    M
  5750   10.6  51.1   225    4    2  -9.6  -5.2   12.7  54.8    -7.4      M    M
  5500    8.5  47.3   165    2    1 -40.3 -22.1   10.0  50.0   -10.2     20  0.1

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

           05/17/2015 at 0900 MDT          |       05/17/2015 at 1200 MDT
                                           |
K index... +23.3  LI... +273.6             | K index... +19.8  LI... +274.1
CAPE... 0.0  CIN... -0.2                   | CAPE... +4.8  CIN... -25.7
                                           |
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 -54.2 -65.6  230  20 10   1.1   0.6 | -55.1 -67.2  230  24 13   1.0   0.6
 45000 -52.3 -62.1  250  26 14   3.2   1.7 | -53.4 -64.1  255  28 15   2.3   1.3
 40000 -47.7 -53.9  270  38 19   3.0   1.7 | -50.0 -58.0  270  44 23   2.2   1.2
 38000 -47.9 -54.2  275  42 22  -3.3  -1.8 | -50.3 -58.5  275  50 26  -2.5  -1.4
 36000 -50.0 -58.0  280  46 24  -3.4  -1.8 | -51.8 -61.2  275  54 28  -2.5  -1.4
 34000 -51.6 -60.9  280  50 26   3.6   2.0 | -52.6 -62.7  280  58 30   6.4   3.5
 32000 -49.1 -56.4  285  56 29   4.1   2.3 | -49.2 -56.6  280  60 31   5.6   3.1
 30000 -45.8 -50.4  285  59 30   7.8   4.3 | -45.0 -49.0  280  59 30   8.4   4.6
 29000 -43.4 -46.1  280  53 27   7.9   4.4 | -42.4 -44.3  280  55 28   8.4   4.6
 28000 -41.1 -42.0  280  47 24   7.9   4.4 | -39.9 -39.8  285  52 27   8.4   4.6
 27000 -38.7 -37.7  275  42 21   8.4   4.6 | -37.4 -35.3  285  48 25   8.3   4.5
 26000 -36.0 -32.8  270  38 20   8.9   4.9 | -34.9 -30.8  275  45 23   8.3   4.5
 25000 -33.4 -28.1  265  35 18   9.0   4.9 | -32.5 -26.5  270  42 22   8.3   4.5
 24000 -30.7 -23.3  260  32 17   8.7   4.8 | -30.0 -22.0  260  41 21   8.6   4.7
 23000 -28.3 -18.9  260  30 16   7.8   4.3 | -27.3 -17.1  265  39 20   9.0   5.0
 22000 -26.0 -14.8  265  29 15   7.9   4.3 | -24.6 -12.3  270  37 19   9.0   5.0
 21000 -23.7 -10.7  265  27 14   7.7   4.2 | -21.9  -7.4  275  36 18   7.8   4.3
 20000 -21.4  -6.5  270  26 14   7.6   4.2 | -19.7  -3.5  275  35 18   7.7   4.2
 19500 -20.3  -4.5  270  26 13   7.6   4.2 | -18.5  -1.3  280  35 18   7.7   4.2
 19000 -19.2  -2.6  275  26 13   7.6   4.2 | -17.4   0.7  280  35 18   7.7   4.2
 18500 -18.1  -0.6  275  26 13   7.6   4.1 | -16.3   2.7  280  34 18   6.7   3.7
 18000 -17.0   1.4  275  25 13   7.5   4.1 | -15.4   4.3  280  34 18   6.1   3.3
 17500 -15.9   3.4  275  25 13   7.5   4.1 | -14.5   5.9  280  34 17   6.1   3.3
 17000 -14.8   5.4  280  25 13   6.9   3.8 | -13.7   7.3  285  33 17   5.5   3.0
 16500 -13.8   7.2  285  25 13   6.9   3.8 | -12.9   8.8  285  33 17   5.5   3.0
 16000 -12.3   9.9  290  24 13   7.1   3.9 | -11.5  11.3  290  32 17   7.0   3.8
 15500 -11.2  11.8  290  24 12   7.1   3.9 | -10.5  13.1  290  33 17   6.9   3.8
 15000 -10.2  13.6  295  24 12   7.3   4.0 |  -9.4  15.1  290  33 17   7.3   4.0
 14500  -9.1  15.6  295  24 12   7.3   4.0 |  -8.4  16.9  295  32 17   7.2   4.0
 14000  -8.0  17.6  300  23 12   7.4   4.1 |  -7.3  18.9  295  32 17   7.5   4.1
 13500  -6.9  19.6  305  24 12   7.4   4.1 |  -6.2  20.8  295  31 16   7.6   4.2
 13000  -5.8  21.6  305  24 12   7.8   4.3 |  -5.1  22.8  295  30 15   7.4   4.1
 12500  -4.6  23.7  310  24 12   8.1   4.4 |  -4.0  24.8  300  29 15   7.4   4.0
 12000  -3.4  25.9  310  24 12   8.3   4.6 |  -2.9  26.8  300  27 14   7.5   4.1
 11500  -2.1  28.2  315  23 12   8.6   4.7 |  -1.8  28.8  300  25 13   7.6   4.1
 11000  -0.9  30.4  315  23 12   7.5   4.1 |  -0.7  30.7  300  23 12   6.9   3.8
 10500   0.1  32.2  315  23 12   5.8   3.2 |   0.2  32.4  300  20 11   6.0   3.3
 10250   0.5  32.9  315  23 12   8.3   4.5 |   0.7  33.3  300  19 10   8.4   4.6
 10000   1.2  34.2  315  23 12   9.5   5.2 |   1.4  34.5  305  17  9   8.7   4.8
  9750   1.8  35.2  315  23 12   7.8   4.3 |   1.9  35.4  305  15  8   6.5   3.6
  9500   2.4  36.3  315  23 12   8.3   4.5 |   2.4  36.3  305  13  7   7.3   4.0
  9250   3.0  37.4  315  23 12   7.9   4.4 |   2.9  37.2  310  12  6   6.3   3.5
  9000   3.6  38.5  315  22 12   7.4   4.1 |   3.3  37.9  315  10  5   6.5   3.6
  8750   4.1  39.4  315  22 11   7.4   4.1 |   3.9  39.0  320   8  4   7.9   4.4
  8500   4.7  40.5  315  21 11   7.6   4.2 |   4.4  39.9  325   6  3   7.5   4.1
  8250   5.2  41.4  315  21 11   7.4   4.1 |   5.0  41.0  340   5  2   9.2   5.0
  8000   5.8  42.4  315  20 10   7.0   3.8 |   5.7  42.3  345   4  2  10.8   5.9
  7750   6.3  43.3  320  18 10   6.5   3.6 |   6.5  43.7  345   4  2   9.5   5.2
  7500   6.7  44.1  320  17  9   6.1   3.3 |   7.2  45.0  345   4  2   9.1   5.0
  7250   7.2  45.0  320  16  8   7.0   3.9 |   7.9  46.2  345   4  2  10.4   5.7
  7000   7.8  46.0  325  14  7   8.1   4.4 |   8.7  47.7  345   4  2  11.2   6.1
  6750   8.3  46.9  325  13  7   6.6   3.6 |   9.5  49.1  350   4  2   9.4   5.2
  6500   8.8  47.8  325  11  6   6.4   3.5 |  10.1  50.2  345   4  2   9.5   5.2
  6250   9.3  48.7  330  10  5   7.7   4.2 |  10.9  51.6  345   4  2  11.4   6.3
  6000   9.8  49.6  325   7  4   8.3   4.6 |  11.8  53.2  345   4  2  11.1   6.1
  5750  10.4  50.7  320   5  3   7.4   4.1 |  12.6  54.7  345   4  2  11.6   6.4
  5500  10.9  51.6  305   3  2   9.5   5.2 |  13.6  56.5  345   4  2  18.3  10.0

           05/17/2015 at 1500 MDT          |       05/17/2015 at 1800 MDT
                                           |
K index... +18.8  LI... +272.7             | K index... +20.2  LI... +271.7
CAPE... +66.7  CIN... -24.6                | CAPE... +141.1  CIN... -30.0
                                           |
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 -55.2 -67.4  240  23 12   0.8   0.4 | -55.9 -68.6  245  26 13   1.0   0.5
 45000 -54.0 -65.2  250  26 13   1.3   0.7 | -54.6 -66.3  255  36 19  -0.2  -0.1
 40000 -52.1 -61.8  275  51 26   1.3   0.7 | -54.8 -66.6  270  51 26  -0.2  -0.1
 38000 -52.0 -61.6  275  56 29  -0.5  -0.3 | -53.9 -65.0  275  54 28   2.6   1.4
 36000 -52.3 -62.1  275  58 30  -0.5  -0.3 | -52.3 -62.1  280  57 29   2.6   1.4
 34000 -51.8 -61.2  275  58 30   5.9   3.3 | -49.8 -57.6  280  56 29   5.9   3.2
 32000 -47.8 -54.0  280  53 27   5.8   3.2 | -46.3 -51.3  275  48 25   5.9   3.2
 30000 -43.8 -46.8  280  49 25   8.4   4.6 | -42.2 -44.0  275  40 21   8.1   4.4
 29000 -41.2 -42.2  280  46 24   8.4   4.6 | -39.8 -39.6  275  37 19   8.1   4.4
 28000 -38.7 -37.7  285  43 22   8.4   4.6 | -37.4 -35.3  275  33 17   8.1   4.4
 27000 -36.2 -33.2  285  41 21   8.7   4.8 | -35.0 -31.0  275  30 15   8.5   4.6
 26000 -33.6 -28.5  285  39 20   8.7   4.8 | -32.4 -26.3  280  28 14   8.4   4.6
 25000 -31.0 -23.8  280  37 19   8.7   4.8 | -29.9 -21.8  280  26 13   8.4   4.6
 24000 -28.4 -19.1  280  35 18   8.5   4.6 | -27.4 -17.3  285  24 13   8.0   4.4
 23000 -25.9 -14.6  280  35 18   8.4   4.6 | -25.0 -13.0  285  27 14   8.0   4.4
 22000 -23.4 -10.1  280  36 18   8.4   4.6 | -22.7  -8.9  285  29 15   8.0   4.4
 21000 -21.0  -5.8  280  36 18   7.0   3.8 | -20.4  -4.7  285  30 16   6.6   3.6
 20000 -18.8  -1.8  285  34 17   7.1   3.9 | -18.5  -1.3  285  30 16   6.8   3.7
 19500 -17.8  -0.0  285  33 17   7.1   3.9 | -17.5   0.5  285  30 16   6.8   3.7
 19000 -16.7   1.9  285  32 16   7.2   3.9 | -16.5   2.3  290  30 16   6.8   3.7
 18500 -15.7   3.7  285  31 16   6.6   3.6 | -15.5   4.1  290  30 16   7.0   3.8
 18000 -14.7   5.5  285  30 16   6.5   3.6 | -14.4   6.1  285  29 15   7.0   3.8
 17500 -13.8   7.2  285  30 15   6.5   3.6 | -12.8   9.0  285  28 14   7.3   4.0
 17000 -12.4   9.7  285  29 15   6.6   3.6 | -11.7  10.9  285  27 14   7.4   4.0
 16500 -11.4  11.5  285  29 15   6.6   3.6 | -10.7  12.7  280  25 13   7.5   4.1
 16000 -10.4  13.3  285  29 15   6.6   3.6 |  -9.5  14.9  280  25 13   7.6   4.1
 15500  -9.4  15.1  285  29 15   6.7   3.7 |  -8.4  16.9  280  24 12   7.6   4.2
 15000  -8.4  16.9  285  29 15   7.3   4.0 |  -7.3  18.9  275  22 11   8.0   4.4
 14500  -7.4  18.7  285  28 15   7.2   3.9 |  -6.1  21.0  275  20 11   8.0   4.4
 14000  -6.2  20.8  285  27 14   8.5   4.7 |  -4.9  23.2  270  19 10   7.6   4.2
 13500  -5.0  23.0  285  26 13   8.5   4.7 |  -3.8  25.2  270  17  9   7.6   4.2
 13000  -3.8  25.2  285  24 12   8.0   4.4 |  -2.7  27.1  260  15  8   8.1   4.5
 12500  -2.6  27.3  285  22 11   8.0   4.4 |  -1.5  29.3  255  14  7   8.2   4.5
 12000  -1.5  29.3  285  19 10   7.7   4.2 |  -0.3  31.5  250  13  6   7.8   4.3
 11500  -0.4  31.3  285  16  8   7.7   4.2 |   0.9  33.6  245  11  6   7.8   4.3
 11000   0.7  33.3  285  13  7   7.6   4.2 |   2.0  35.6  235  10  5   8.1   4.4
 10500   1.8  35.2  280  10  5   8.1   4.5 |   3.2  37.8  230   8  4   8.8   4.8
 10250   2.4  36.3  280   8  4   5.4   2.9 |   3.8  38.8  225   8  4   5.3   2.9
 10000   2.7  36.9  280   7  4   5.8   3.2 |   4.1  39.4  220   7  4   6.1   3.3
  9750   3.3  37.9  275   6  3   8.8   4.8 |   4.8  40.6  220   7  3  10.0   5.5
  9500   3.8  38.8  270   4  2   8.1   4.5 |   5.5  41.9  210   6  3   9.3   5.1
  9250   4.4  39.9  250   2  1   7.8   4.3 |   6.1  43.0  205   5  3   8.4   4.6
  9000   5.0  41.0  240   2  1   8.6   4.7 |   6.7  44.1  200   5  2   7.7   4.2
  8750   5.7  42.3  240   2  1   9.9   5.4 |   7.3  45.1  200   4  2   8.3   4.6
  8500   6.4  43.5  245   2  1   9.6   5.3 |   7.8  46.0  200   3  2   8.2   4.5
  8250   7.1  44.8  245   2  1  10.1   5.5 |   8.4  47.1  195   3  1   8.7   4.8
  8000   7.9  46.2  245   1  1  10.3   5.6 |   9.1  48.4  195   2  1   9.2   5.1
  7750   8.6  47.5  250   1  1   9.7   5.3 |   9.7  49.5  195   2  1   9.4   5.2
  7500   9.3  48.7  250   2  1   9.7   5.3 |  10.4  50.7  195   2  1   9.7   5.3
  7250  10.1  50.2  250   2  1  10.1   5.6 |  11.1  52.0  200   2  1  10.0   5.5
  7000  10.8  51.4  255   2  1  10.3   5.7 |  11.9  53.4  205   1  1  10.1   5.5
  6750  11.6  52.9  255   2  1   9.8   5.4 |  12.6  54.7  205   1  1   9.7   5.3
  6500  12.3  54.1  260   1  1  10.2   5.6 |  13.4  56.1  210   1  1  10.0   5.5
  6250  13.1  55.6  260   1  1  11.0   6.1 |  14.1  57.4  215   1  1  10.6   5.8
  6000  13.9  57.0  260   1  1  10.2   5.6 |  14.9  58.8  220   1  1  10.3   5.6
  5750  14.7  58.5  260   1  1  12.6   6.9 |  15.7  60.3  225   1  1  10.6   5.8
  5500  15.9  60.6  270   1  1  21.3  11.7 |  16.5  61.7  225   1  1  13.0   7.1
________________________________________________________________________________

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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