Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 181216
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0616 MDT Friday, April 18, 2014

This forecast is for Friday, April 18, 2014:

If the trigger temperature of 65.6 F/18.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1440 ft/min (7.3 m/s)
   Maximum height of thermals.................. 20649 ft MSL (15364 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1045 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................. 12122 ft MSL (6837 ft AGL)
Thermal soaring outlook for Saturday 04/19..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing high clouds
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 15391 ft MSL (10106 ft AGL)
Wave soaring outlook for Saturday 04/19........ Poor

Remarks...

Sunrise/Sunset.................... 06:17:32 / 19:39:46 MDT
Total possible sunshine........... 13 hr 22 min 14 sec (802 min 14 sec)
Altitude of sun at 12:58:49 MDT... 61.23 degrees

Upper air data from rawinsonde observation taken on 04/18/2014 at 0600 MDT

Freezing level.................. 12856 ft MSL (7571 ft AGL)
Convective condensation level... 18604 ft MSL (13319 ft AGL)
Lifted condensation level....... 18914 ft MSL (13629 ft AGL)
Lifted index.................... +2.5
K index......................... +0.3

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  -62.6 -80.7   260   14    7   9.0   4.9   94.6 202.3    39.5      M    M
 45000  -60.2 -76.4   285   18    9   7.3   4.0   73.8 164.9    29.6      M    M
 40000  -67.0 -88.6   290   42   21   7.3   4.0   40.1 104.1     9.6      M    M
 38000  -62.5 -80.5   285   35   18   9.1   5.0   37.9 100.2     8.4      M    M
 36000  -57.1 -70.8   275   35   18   7.5   4.1   37.3  99.1     8.2      M    M
 34000  -52.5 -62.5   280   33   17   8.2   4.5   35.5  95.9     7.1      M    M
 32000  -46.7 -52.1   285   29   15   8.6   4.7   34.4  93.9     6.5      M    M
 30000  -41.3 -42.3   285   27   14   9.4   5.1   33.9  93.1     6.3      M    M
 29000  -38.5 -37.3   285   27   14   9.4   5.1   33.5  92.4     6.1      M    M
 28000  -35.7 -32.3   285   27   14   9.4   5.1   33.3  91.9     6.0      M    M
 27000  -32.9 -27.2   290   27   14   9.4   5.1   33.1  91.7     6.0      M    M
 26000  -30.1 -22.2   290   27   14   9.4   5.1   33.1  91.6     6.0      M    M
 25000  -27.3 -17.1   290   27   14   9.4   5.1   33.2  91.8     6.1      M    M
 24000  -24.5 -12.1   290   27   14   7.8   4.3   32.8  91.0     5.9      M    M
 23000  -22.2  -8.0   290   29   15   7.9   4.3   32.1  89.7     5.4      M    M
 22000  -19.8  -3.6   285   30   16   6.4   3.5   31.5  88.7     4.9      M    M
 21000  -20.3  -4.5   285   32   16 -10.5  -5.7   27.4  81.3     1.5      M    M
 20000  -19.2  -2.6   315   21   11   9.9   5.4   25.3  77.6    -0.3   1381  7.0
 19500  -17.7   0.1   325   20   10   9.9   5.4   25.3  77.6    -0.3   1322  6.7
 19000  -16.3   2.7   330   19   10   9.9   5.4   25.3  77.6    -0.3   1263  6.4
 18500  -14.8   5.4   330   18    9   9.1   5.0   25.3  77.6    -0.3   1205  6.1
 18000  -13.5   7.7   335   17    9   9.2   5.0   25.2  77.4    -0.4   1149  5.8
 17500  -12.1  10.2   335   16    8   9.2   5.0   25.1  77.2    -0.5   1093  5.6
 17000  -10.7  12.7   340   15    8   9.2   5.0   25.0  77.0    -0.6   1037  5.3
 16500   -9.3  15.3   340   14    7   9.2   5.0   24.9  76.9    -0.7    981  5.0
 16000   -7.3  18.9   345   13    7   9.2   5.0   24.8  76.7    -0.8    897  4.6
 15500   -5.9  21.4   330   12    6   9.1   5.0   24.7  76.5    -0.9    841  4.3
 15000   -4.5  23.9   320   11    6   8.3   4.5   24.6  76.3    -1.0    785  4.0
 14500   -3.6  25.5   305   11    6   6.0   3.3   24.1  75.3    -1.6    741  3.8
 14000   -2.6  27.3   295   12    6   7.8   4.3   23.6  74.4    -2.1    697  3.5
 13500   -1.4  29.5   310   12    6   8.1   4.5   23.3  74.0    -2.3    646  3.3
 13000   -0.2  31.6   320   14    7   8.2   4.5   23.1  73.5    -2.6    595  3.0
 12500    1.0  33.8   315   18    9   8.2   4.5   22.8  73.1    -2.8    544  2.8
 12000    2.3  36.1   310   22   11   8.2   4.5   22.6  72.6    -3.1    493  2.5
 11500    3.5  38.3   305   25   13   8.6   4.7   22.3  72.1    -3.4    441  2.2
 11000    4.3  39.7   300   27   14  -0.4  -0.2   21.6  71.0    -4.0    401  2.0
 10500    4.2  39.6   295   21   11   4.6   2.5   20.0  68.0    -5.6    390  2.0
 10250    4.7  40.5   295   19   10   6.1   3.3   19.7  67.5    -5.9    369  1.9
 10000    5.1  41.2   295   17    9   5.6   3.1   19.4  66.9    -6.3    350  1.8
  9750    5.6  42.1   295   15    8   8.2   4.5   19.2  66.5    -6.5    326  1.7
  9500    6.2  43.2   295   13    7   8.8   4.8   19.1  66.4    -6.6    299  1.5
  9250    6.9  44.4   290   11    6   8.6   4.7   19.0  66.2    -6.6    272  1.4
  9000    7.5  45.5   290    9    5   8.7   4.8   19.0  66.1    -6.7    246  1.2
  8750    8.2  46.8   290    9    4   8.7   4.8   18.9  66.0    -6.8    219  1.1
  8500    8.8  47.8   290    8    4   8.7   4.8   18.8  65.8    -6.9    192  1.0
  8250    9.5  49.1   285    8    4   8.7   4.8   18.7  65.7    -7.0    165  0.8
  8000   10.1  50.2   285    8    4   8.7   4.8   18.7  65.6    -7.1    138  0.7
  7750   10.8  51.4   275   10    5   8.7   4.8   18.6  65.4    -7.2    112  0.6
  7500   11.4  52.5   270   13    7   8.7   4.8   18.5  65.3    -7.3     85  0.4
  7250   12.1  53.8   270   15    8   8.6   4.7   18.4  65.1    -7.4     58  0.3
  7000   12.7  54.9   265   18    9   8.8   4.8   18.3  65.0    -7.5     31  0.2
  6750   13.4  56.1   260   16    8   8.1   4.5   18.2  64.8    -7.7      4  0.0
  6500   14.0  57.2   255   15    8  10.8   5.9   18.1  64.6    -7.8      M    M
  6250   14.5  58.1   250   13    7  -5.0  -2.7   17.9  64.2    -8.0      M    M
  6000   13.3  55.9   240   12    6 -18.5 -10.1   16.0  60.7   -10.0      M    M
  5750   12.0  53.6   235    9    5 -16.7  -9.1   14.0  57.2   -12.0     15  0.1
  5500   10.2  50.4   225    6    3 -35.0 -19.2   11.5  52.7   -14.6     63  0.3

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

           04/18/2014 at 0900 MDT          |       04/18/2014 at 1200 MDT
                                           |
K index... +3.3  LI... +3.0                | K index... +3.5  LI... +1.0
CAPE... 0.0  CIN... M                      | 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 -60.8 -77.4  275  20 10   1.3   0.7 | -62.1 -79.8  265  23 12   0.5   0.3
 45000 -59.0 -74.2  275  27 14  -2.6  -1.4 | -61.5 -78.7  265  28 14  -1.3  -0.7
 40000 -63.7 -82.7  275  36 18  -3.1  -1.7 | -63.5 -82.3  255  34 18  -1.2  -0.7
 38000 -61.3 -78.3  275  38 19   7.7   4.2 | -60.4 -76.7  255  35 18   8.2   4.5
 36000 -56.6 -69.9  270  39 20   7.7   4.2 | -55.5 -67.9  260  36 19   8.2   4.5
 34000 -51.3 -60.3  265  38 20   8.1   4.5 | -50.2 -58.4  260  36 19   7.3   4.0
 32000 -46.4 -51.5  265  35 18   8.1   4.5 | -45.8 -50.4  250  36 19   7.3   4.0
 30000 -41.4 -42.5  265  32 16   8.6   4.7 | -41.1 -42.0  245  34 17   8.3   4.5
 29000 -38.8 -37.8  265  30 16   8.6   4.7 | -38.7 -37.7  245  31 16   8.3   4.5
 28000 -36.2 -33.2  265  29 15   8.7   4.7 | -36.2 -33.2  245  28 15   8.3   4.6
 27000 -33.5 -28.3  265  27 14   9.1   5.0 | -33.6 -28.5  240  27 14   8.7   4.8
 26000 -30.8 -23.4  265  26 13   9.1   5.0 | -31.0 -23.8  240  25 13   8.7   4.8
 25000 -28.1 -18.6  265  24 12   9.1   5.0 | -28.4 -19.1  240  24 13   8.7   4.8
 24000 -25.4 -13.7  265  23 12   7.8   4.3 | -25.8 -14.4  240  23 12   8.1   4.4
 23000 -23.1  -9.6  270  21 11   7.9   4.4 | -23.4 -10.1  245  21 11   8.2   4.5
 22000 -20.7  -5.3  270  19 10   7.9   4.3 | -20.9  -5.6  245  20 10   8.1   4.5
 21000 -18.5  -1.3  275  17  9   6.5   3.6 | -18.6  -1.5  245  19 10   7.3   4.0
 20000 -16.5   2.3  270  15  8   6.6   3.6 | -16.4   2.5  240  19 10   7.3   4.0
 19500 -15.5   4.1  270  14  7   6.6   3.6 | -15.3   4.5  240  19 10   7.3   4.0
 19000 -14.5   5.9  270  13  7   6.6   3.6 | -14.2   6.4  240  19 10   7.3   4.0
 18500 -13.5   7.7  270  12  6   7.0   3.8 | -13.1   8.4  240  19 10   7.1   3.9
 18000 -12.5   9.5  265  12  6   7.0   3.8 | -12.1  10.2  240  19 10   7.2   3.9
 17500 -11.5  11.3  265  11  6   7.2   3.9 | -11.0  12.2  240  19 10   7.3   4.0
 17000 -10.4  13.3  265  11  6   7.3   4.0 |  -9.4  15.1  235  19 10   7.4   4.0
 16500  -8.7  16.3  265  10  5   7.5   4.1 |  -8.3  17.1  235  19 10   7.5   4.1
 16000  -7.6  18.3  265  10  5   7.5   4.1 |  -7.2  19.0  235  18  9   7.6   4.2
 15500  -6.5  20.3  265  10  5   7.5   4.1 |  -6.0  21.2  235  18  9   7.5   4.1
 15000  -5.4  22.3  270  10  5   7.5   4.1 |  -4.9  23.2  230  17  9   7.4   4.1
 14500  -4.3  24.3  270   9  5   7.5   4.1 |  -3.8  25.2  230  16  8   7.4   4.1
 14000  -3.1  26.4  275   9  4   8.3   4.6 |  -2.8  27.0  225  15  8   7.4   4.1
 13500  -1.9  28.6  280   8  4   8.3   4.5 |  -1.7  28.9  225  14  7   7.4   4.1
 13000  -0.7  30.7  285   8  4   8.2   4.5 |  -0.5  31.1  225  13  6   8.3   4.5
 12500   0.6  33.1  290   8  4   8.1   4.5 |   0.7  33.3  225  11  6   8.1   4.4
 12000   1.9  35.4  295   8  4   9.4   5.1 |   2.0  35.6  230  10  5   9.2   5.1
 11500   3.3  37.9  300   9  4   9.4   5.1 |   3.4  38.1  235   9  5   9.1   5.0
 11000   4.6  40.3  305   9  5   9.2   5.0 |   4.8  40.6  240   9  5   9.5   5.2
 10500   6.0  42.8  305  10  5  10.1   5.5 |   6.2  43.2  245   9  5  10.1   5.5
 10250   6.7  44.1  310  11  6   5.6   3.1 |   6.9  44.4  245   9  4   6.9   3.8
 10000   6.9  44.4  305  11  6   6.4   3.5 |   7.3  45.1  250   9  4   7.9   4.3
  9750   7.7  45.9  305  12  6  11.2   6.2 |   8.1  46.6  250   9  4  11.7   6.4
  9500   8.4  47.1  305  13  7  10.6   5.8 |   8.9  48.0  250   9  4  11.0   6.0
  9250   9.2  48.6  305  14  7   8.3   4.6 |   9.7  49.5  250   9  4   9.5   5.2
  9000   9.7  49.5  300  14  7   7.5   4.1 |  10.3  50.5  255   9  4   8.9   4.9
  8750  10.4  50.7  300  14  7   9.6   5.2 |  11.0  51.8  255   9  4  10.1   5.6
  8500  11.0  51.8  295  14  7   9.0   4.9 |  11.8  53.2  260   8  4   9.6   5.3
  8250  11.7  53.1  295  14  7   9.7   5.3 |  12.4  54.3  260   8  4   8.3   4.6
  8000  12.4  54.3  295  14  7   9.5   5.2 |  13.0  55.4  250   7  4   7.6   4.1
  7750  13.1  55.6  290  15  8   9.0   4.9 |  13.5  56.3  245   7  4   7.5   4.1
  7500  13.8  56.8  290  15  8   7.7   4.2 |  14.1  57.4  235   7  3   8.4   4.6
  7250  14.2  57.6  290  15  8   5.8   3.2 |  14.7  58.5  230   6  3   9.9   5.4
  7000  14.6  58.3  290  15  8   4.5   2.5 |  15.4  59.7  220   6  3  10.1   5.5
  6750  15.0  59.0  285  15  8   5.2   2.9 |  16.2  61.2  215   6  3   9.6   5.3
  6500  15.1  59.2  285  14  7  -4.4  -2.4 |  16.9  62.4  215   6  3  10.2   5.6
  6250  14.3  57.7  275  11  6 -12.1  -6.7 |  17.7  63.9  215   6  3  11.1   6.1
  6000  13.5  56.3  260   9  5 -11.1  -6.1 |  18.5  65.3  215   6  3  10.1   5.5
  5750  12.5  54.5  235   8  4 -11.3  -6.2 |  19.3  66.7  215   6  3  12.8   7.0
  5500  11.9  53.4  215   8  4  -2.7  -1.5 |  20.5  68.9  215   6  3  21.2  11.6

           04/18/2014 at 1500 MDT          |       04/18/2014 at 1800 MDT
                                           |
K index... +18.6  LI... -0.1               | K index... +20.1  LI... -0.6
CAPE... +0.9  CIN... M                     | CAPE... +24.6  CIN... -24.5
                                           |
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 -62.1 -79.8  260  30 16  -0.2  -0.1 | -62.1 -79.8  265  34 18  -0.3  -0.2
 45000 -62.5 -80.5  270  40 20  -1.0  -0.5 | -62.6 -80.7  265  44 23  -0.5  -0.3
 40000 -64.1 -83.4  255  52 27  -1.2  -0.6 | -63.4 -82.1  255  55 28  -0.7  -0.4
 38000 -60.0 -76.0  255  50 26   9.0   4.9 | -59.2 -74.6  255  53 28   9.1   5.0
 36000 -54.6 -66.3  250  45 23   9.0   4.9 | -53.8 -64.8  255  51 26   9.1   5.0
 34000 -49.6 -57.3  250  42 22   7.6   4.2 | -48.9 -56.0  250  47 24   7.0   3.8
 32000 -45.0 -49.0  245  41 21   7.6   4.2 | -44.7 -48.5  245  44 23   7.0   3.8
 30000 -40.4 -40.7  240  38 20   7.9   4.3 | -40.2 -40.4  235  41 21   8.2   4.5
 29000 -38.0 -36.4  235  36 19   7.9   4.3 | -37.8 -36.0  235  40 20   8.2   4.5
 28000 -35.7 -32.3  230  34 18   7.9   4.3 | -35.3 -31.5  230  38 20   8.2   4.5
 27000 -32.7 -26.9  225  32 17   8.1   4.5 | -32.4 -26.3  230  37 19   7.5   4.1
 26000 -30.3 -22.5  220  30 16   8.1   4.5 | -30.1 -22.2  225  36 18   7.5   4.1
 25000 -27.8 -18.0  220  28 15   8.1   4.5 | -27.9 -18.2  225  34 18   7.5   4.1
 24000 -25.5 -13.9  220  26 14   7.3   4.0 | -25.7 -14.3  225  33 17   7.1   3.9
 23000 -23.3  -9.9  225  23 12   7.4   4.0 | -23.6 -10.5  230  31 16   7.1   3.9
 22000 -21.1  -6.0  225  21 11   7.4   4.0 | -21.4  -6.5  230  30 15   7.2   3.9
 21000 -18.9  -2.0  230  20 10   6.9   3.8 | -19.3  -2.7  235  28 14   7.3   4.0
 20000 -16.9   1.6  240  21 11   6.9   3.8 | -17.1   1.2  235  26 13   7.3   4.0
 19500 -15.8   3.6  240  22 11   6.9   3.8 | -16.1   3.0  240  25 13   7.3   4.0
 19000 -14.8   5.4  245  22 12   7.0   3.8 | -15.0   5.0  240  24 12   7.3   4.0
 18500 -13.8   7.2  245  23 12   7.0   3.8 | -13.9   7.0  240  23 12   7.2   4.0
 18000 -12.8   9.0  250  23 12   7.0   3.8 | -12.9   8.8  245  21 11   7.3   4.0
 17500 -11.7  10.9  250  23 12   7.9   4.3 | -11.8  10.8  250  19 10   8.0   4.4
 17000 -10.6  12.9  250  22 11   8.1   4.4 | -10.6  12.9  250  17  9   8.3   4.6
 16500  -9.4  15.1  250  21 11   8.2   4.5 |  -9.4  15.1  250  15  8   8.5   4.7
 16000  -8.2  17.2  250  20 10   8.4   4.6 |  -8.1  17.4  250  15  8   9.1   5.0
 15500  -7.0  19.4  250  18  9   8.4   4.6 |  -6.8  19.8  250  14  7   9.0   5.0
 15000  -5.7  21.7  250  16  8   9.0   4.9 |  -5.5  22.1  250  13  7   9.3   5.1
 14500  -4.4  24.1  245  15  8   8.9   4.9 |  -4.1  24.6  250  13  7   9.3   5.1
 14000  -2.4  27.7  240  13  7   9.1   5.0 |  -2.0  28.4  250  12  6   9.5   5.2
 13500  -1.1  30.0  235  12  6   9.1   5.0 |  -0.6  30.9  245  12  6   9.5   5.2
 13000   0.3  32.5  230  11  6   9.1   5.0 |   0.8  33.4  245  12  6   9.5   5.2
 12500   1.6  34.9  230  10  5   9.1   5.0 |   2.3  36.1  245  11  6   9.6   5.3
 12000   3.0  37.4  225   9  5   9.5   5.2 |   3.7  38.7  240  11  6   9.1   5.0
 11500   4.4  39.9  220   9  5   9.7   5.3 |   5.0  41.0  240  11  6   9.3   5.1
 11000   5.7  42.3  215   9  5   7.4   4.1 |   6.3  43.3  235  11  5   7.9   4.4
 10500   6.8  44.2  215   9  5   8.3   4.5 |   7.5  45.5  230  10  5   8.4   4.6
 10250   7.5  45.5  210   9  5  11.1   6.1 |   8.2  46.8  230  10  5  12.1   6.6
 10000   8.3  46.9  210   8  4  10.4   5.7 |   9.2  48.6  230  10  5  11.2   6.2
  9750   9.0  48.2  210   8  4   8.7   4.8 |   9.8  49.6  225  10  5   8.3   4.6
  9500   9.6  49.3  205   8  4   9.2   5.0 |  10.5  50.9  225  10  5   9.2   5.1
  9250  10.3  50.5  205   8  4   8.3   4.6 |  11.2  52.2  220   9  5   8.5   4.7
  9000  10.9  51.6  205   8  4   9.4   5.2 |  11.8  53.2  220   9  5   8.5   4.7
  8750  11.7  53.1  205   8  4  10.9   6.0 |  12.4  54.3  220   9  5   9.0   4.9
  8500  12.5  54.5  205   7  4  10.4   5.7 |  13.1  55.6  215   9  4   8.8   4.8
  8250  13.3  55.9  205   7  4  10.3   5.6 |  13.7  56.7  215   8  4   9.6   5.3
  8000  14.0  57.2  205   7  4   9.7   5.3 |  14.5  58.1  215   7  4   9.8   5.4
  7750  14.7  58.5  205   7  4   9.3   5.1 |  15.2  59.4  215   7  4   9.2   5.0
  7500  15.4  59.7  205   7  4   9.7   5.3 |  15.9  60.6  215   7  4   9.4   5.2
  7250  16.2  61.2  205   7  4  10.7   5.9 |  16.6  61.9  215   7  3  10.0   5.5
  7000  17.0  62.6  205   7  4  10.6   5.8 |  17.3  63.1  215   7  3  10.1   5.5
  6750  17.7  63.9  210   7  4   9.1   5.0 |  18.0  64.4  215   6  3   9.4   5.2
  6500  18.4  65.1  210   7  3   9.9   5.4 |  18.7  65.7  220   6  3  10.0   5.5
  6250  19.2  66.6  210   7  3  11.4   6.3 |  19.5  67.1  220   6  3  11.1   6.1
  6000  20.0  68.0  210   6  3  10.4   5.7 |  20.3  68.5  220   6  3  10.8   5.9
  5750  20.8  69.4  210   6  3  12.4   6.8 |  21.1  70.0  220   6  3   9.6   5.3
  5500  22.0  71.6  210   6  3  19.8  10.9 |  21.8  71.2  225   6  3   9.6   5.3
________________________________________________________________________________

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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