Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191328
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0728 MDT Wednesday, April 19, 2017

This forecast is for Wednesday, April 19, 2017:

If the trigger temperature of 68.2 F/20.1 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 673 ft/min (3.4 m/s)
   Maximum height of thermals.................. 13103 ft MSL (7818 ft AGL)

Forecast maximum temperature................... 72.0 F/22.7 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 6658 ft MSL (1373 ft AGL)
Thermal soaring outlook for Thursday 04/20..... Fair

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 12674 ft MSL (7389 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14398 ft MSL (9113 ft AGL)
Wave soaring outlook for Thursday 04/20........ Poor

Remarks...

Sunrise/Sunset.................... 06:15:14 / 19:41:45 MDT
Total possible sunshine........... 13 hr 26 min 32 sec (806 min 32 sec)
Altitude of sun at 12:58:30 MDT... 61.67 degrees

Upper air data from rawinsonde observation taken on 04/19/2017 at 0600 MDT

Freezing level.................. 12175 ft MSL (6890 ft AGL)
Convective condensation level... 19077 ft MSL (13792 ft AGL)
Lifted condensation level....... 16371 ft MSL (11085 ft AGL)
Lifted index.................... +3.1
K index......................... -0.4

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  -61.4 -78.5   260   32   17   6.8   3.7   94.5 202.1    41.6      M    M
 45000  -58.0 -72.4   275   79   41   0.6   0.3   74.5 166.2    32.4      M    M
 40000  -51.5 -60.7   270  109   56   0.9   0.5   61.8 143.2    26.2      M    M
 38000  -51.4 -60.5   265   93   48   0.7   0.4   53.2 127.7    21.0      M    M
 36000  -52.8 -63.0   265   83   42   7.1   3.9   42.5 108.6    14.2      M    M
 34000  -48.5 -55.3   265   81   42   7.4   4.1   40.2 104.4    12.9      M    M
 32000  -43.5 -46.3   270   80   41   7.4   4.1   38.0 100.5    11.7      M    M
 30000  -38.8 -37.8   270   75   38   8.0   4.4   36.6  97.9    10.9      M    M
 29000  -36.4 -33.5   270   72   37   8.0   4.4   35.7  96.2    10.3      M    M
 28000  -34.0 -29.2   270   68   35   8.0   4.4   34.9  94.8     9.9      M    M
 27000  -31.6 -24.9   265   65   34   8.0   4.4   34.3  93.7     9.5      M    M
 26000  -29.2 -20.6   265   62   32   8.0   4.4   33.7  92.7     9.2      M    M
 25000  -26.8 -16.2   265   59   30   8.0   4.4   33.3  91.9     8.9      M    M
 24000  -24.5 -12.1   270   50   26   6.7   3.7   32.5  90.4     8.3      M    M
 23000  -22.4  -8.3   265   44   23   7.2   3.9   31.5  88.6     7.6      M    M
 22000  -20.2  -4.4   260   39   20   8.4   4.6   30.6  87.1     7.0      M    M
 21000  -17.5   0.5   255   33   17   9.0   5.0   30.4  86.8     6.9      M    M
 20000  -14.8   5.4   250   33   17   9.0   5.0   30.2  86.4     6.8      M    M
 19500  -13.4   7.9   250   33   17   9.0   5.0   30.1  86.1     6.7      M    M
 19000  -12.0  10.4   255   32   17   9.1   5.0   29.9  85.9     6.6      M    M
 18500  -10.7  12.7   255   32   17   7.9   4.4   29.7  85.5     6.5      M    M
 18000   -9.6  14.7   255   33   17   7.8   4.3   29.4  84.9     6.2      M    M
 17500   -8.6  16.5   255   33   17   5.9   3.2   28.9  84.0     5.8      M    M
 17000   -7.7  18.1   260   34   17   6.1   3.3   28.2  82.8     5.2      M    M
 16500   -6.8  19.8   260   34   18   6.1   3.3   27.6  81.7     4.7      M    M
 16000   -5.9  21.4   260   35   18   6.1   3.4   27.0  80.7     4.2      M    M
 15500   -4.5  23.9   260   38   19   6.1   3.4   26.1  79.0     3.3      M    M
 15000   -3.6  25.5   265   40   21   6.2   3.4   25.5  77.8     2.8      M    M
 14500   -2.7  27.1   265   42   22   6.2   3.4   24.9  76.8     2.2      M    M
 14000   -1.8  28.8   265   43   22   6.1   3.4   24.3  75.8     1.7      M    M
 13500   -1.3  29.7   265   40   21   2.0   1.1   23.3  74.0     0.7      M    M
 13000   -1.0  30.2   265   36   19   2.7   1.5   22.1  71.8    -0.4    664  3.4
 12500   -0.7  30.7   265   33   17   5.8   3.2   21.0  69.7    -1.6    640  3.3
 12000    0.7  33.3   265   29   15   9.2   5.0   20.9  69.6    -1.6    584  3.0
 11500    2.1  35.8   265   24   13   9.4   5.2   20.8  69.5    -1.7    527  2.7
 11000    3.5  38.3   265   20   10   9.4   5.2   20.8  69.4    -1.8    470  2.4
 10500    4.9  40.8   265   20   10   9.4   5.2   20.7  69.3    -1.9    413  2.1
 10250    5.6  42.1   265   20   10   9.4   5.2   20.7  69.2    -1.9    385  2.0
 10000    6.3  43.3   265   20   10   9.3   5.1   20.7  69.2    -1.9    356  1.8
  9750    7.0  44.6   265   20   10   9.3   5.1   20.6  69.1    -2.0    328  1.7
  9500    7.7  45.9   270   19   10   9.3   5.1   20.6  69.1    -2.0    300  1.5
  9250    8.4  47.1   270   19   10   9.3   5.1   20.6  69.0    -2.0    272  1.4
  9000    9.1  48.4   270   19   10   9.3   5.1   20.6  69.0    -2.1    244  1.2
  8750    9.8  49.6   270   20   10   9.3   5.1   20.5  68.9    -2.1    216  1.1
  8500   10.4  50.7   275   20   10   9.3   5.1   20.5  68.9    -2.2    187  1.0
  8250   11.1  52.0   275   21   11   9.3   5.1   20.5  68.8    -2.2    159  0.8
  8000   11.8  53.2   275   21   11   9.3   5.1   20.4  68.8    -2.2    131  0.7
  7750   12.5  54.5   275   20   10   9.2   5.1   20.4  68.7    -2.3    103  0.5
  7500   13.2  55.8   275   19   10   9.4   5.2   20.3  68.6    -2.3     75  0.4
  7250   13.9  57.0   270   19   10   8.8   4.8   20.3  68.6    -2.4     47  0.2
  7000   14.6  58.3   270   18    9  11.2   6.1   20.3  68.5    -2.4     19  0.1
  6750   15.3  59.5   270   16    8   2.2   1.2   20.2  68.4    -2.5      M    M
  6500   14.8  58.6   270   15    8  -9.1  -5.0   19.1  66.3    -3.7      M    M
  6250   14.1  57.4   275   13    7  -8.2  -4.5   17.7  63.8    -5.2     12  0.1
  6000   13.4  56.1   275   11    6  -9.0  -4.9   16.3  61.3    -6.6     26  0.1
  5750   12.6  54.7   270    8    4  -6.2  -3.4   14.9  58.9    -8.1     40  0.2
  5500   11.9  53.4   260    4    2 -15.7  -8.6   13.6  56.5    -9.6     55  0.3

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

           04/19/2017 at 0900 MDT          |       04/19/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +6.0        | CAPE...     0.0    LI...       +2.8
CINH...     0.0    K Index...  -4.5        | CINH...     0.0    K Index...   0.0
                                           |
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 -64.4 -83.9  265  32 16   2.8   1.6 | -62.8 -81.0  255  29 15   2.9   1.6
 45000 -59.7 -75.5  265  37 19   5.4   3.0 | -58.3 -72.9  250  39 20   3.8   2.1
 40000 -51.1 -60.0  260  49 25   5.8   3.2 | -52.2 -62.0  255  54 28   3.9   2.1
 38000 -49.3 -56.7  260  50 26   2.4   1.3 | -50.6 -59.1  255  55 28   2.4   1.3
 36000 -47.9 -54.2  260  50 26   2.4   1.3 | -49.1 -56.4  255  56 29   2.4   1.3
 34000 -45.7 -50.3  265  50 26   5.6   3.1 | -46.9 -52.4  255  54 28   6.1   3.4
 32000 -42.3 -44.1  265  48 25   5.6   3.1 | -43.2 -45.8  255  51 26   6.1   3.3
 30000 -38.8 -37.8  260  44 23   6.5   3.5 | -39.4 -38.9  255  47 24   6.7   3.7
 29000 -36.9 -34.4  260  41 21   6.5   3.5 | -37.4 -35.3  255  44 23   6.7   3.7
 28000 -34.9 -30.8  260  39 20   6.4   3.5 | -34.9 -30.8  255  42 21   6.7   3.7
 27000 -32.3 -26.1  255  36 19   8.7   4.7 | -32.8 -27.0  255  39 20   7.5   4.1
 26000 -29.7 -21.5  255  35 18   8.6   4.7 | -30.6 -23.1  255  37 19   7.5   4.1
 25000 -27.1 -16.8  255  35 18   8.6   4.7 | -28.4 -19.1  250  34 17   7.5   4.1
 24000 -24.7 -12.5  255  33 17   6.4   3.5 | -26.1 -15.0  250  31 16   7.6   4.2
 23000 -22.7  -8.9  250  30 15   6.6   3.6 | -23.8 -10.8  250  29 15   7.6   4.2
 22000 -20.7  -5.3  250  26 13   6.6   3.6 | -21.6  -6.9  245  27 14   7.6   4.2
 21000 -18.5  -1.3  245  22 11   9.7   5.3 | -19.2  -2.6  240  26 13   8.4   4.6
 20000 -15.6   3.9  235  17  9   9.5   5.2 | -16.7   1.9  240  25 13   8.4   4.6
 19500 -14.2   6.4  230  15  8   9.5   5.2 | -15.5   4.1  235  24 12   8.4   4.6
 19000 -12.8   9.0  220  14  7   9.6   5.3 | -14.2   6.4  235  24 12   8.4   4.6
 18500 -11.4  11.5  215  13  7   8.1   4.5 | -13.0   8.6  235  23 12   7.9   4.3
 18000 -10.2  13.6  220  13  7   8.1   4.4 | -11.8  10.8  235  23 12   7.9   4.3
 17500  -9.0  15.8  220  13  6   7.2   4.0 | -10.6  12.9  235  22 11   7.7   4.2
 17000  -8.1  17.4  225  12  6   5.6   3.1 |  -9.5  14.9  240  20 11   7.3   4.0
 16500  -7.3  18.9  225  11  6   5.6   3.1 |  -8.4  16.9  240  19 10   7.5   4.1
 16000  -6.5  20.3  230  10  5   5.5   3.0 |  -7.5  18.5  240  17  9   5.8   3.2
 15500  -5.7  21.7  235   9  5   5.5   3.0 |  -6.6  20.1  240  15  8   6.0   3.3
 15000  -4.8  23.4  235   8  4   6.8   3.7 |  -5.7  21.7  240  13  7   5.9   3.2
 14500  -3.7  25.3  240   8  4   7.3   4.0 |  -4.9  23.2  245  12  6   5.9   3.3
 14000  -2.7  27.1  245   7  4   7.5   4.1 |  -4.0  24.8  250  11  6   6.3   3.5
 13500  -1.5  29.3  255   7  4   7.7   4.2 |  -2.5  27.5  260  11  6   7.0   3.8
 13000   0.1  32.2  265   8  4   6.6   3.6 |  -1.6  29.1  265  11  6   6.2   3.4
 12500   1.0  33.8  275   9  4   6.4   3.5 |  -0.7  30.7  265  11  6   6.1   3.4
 12000   2.0  35.6  280  10  5   6.6   3.6 |   0.1  32.2  270  11  5   6.3   3.5
 11500   2.9  37.2  280  12  6   6.7   3.7 |   1.1  34.0  275  11  5   6.4   3.5
 11000   3.8  38.8  280  13  7   4.6   2.5 |   1.9  35.4  280  10  5   5.5   3.0
 10500   4.3  39.7  280  15  8   2.8   1.5 |   2.7  36.9  285  10  5   4.1   2.3
 10250   4.6  40.3  280  16  8   6.7   3.7 |   3.1  37.6  285   9  5   9.6   5.3
 10000   5.2  41.4  280  17  9   7.1   3.9 |   4.0  39.2  290   9  5  11.7   6.4
  9750   5.5  41.9  280  17  9   3.4   1.9 |   4.6  40.3  290   9  5   7.6   4.2
  9500   5.7  42.3  280  18  9   4.4   2.4 |   5.2  41.4  290   9  5   9.2   5.1
  9250   6.0  42.8  280  18  9   4.3   2.4 |   5.8  42.4  295   9  5   7.0   3.8
  9000   6.3  43.3  280  18  9   5.0   2.7 |   6.3  43.3  295   9  5   8.1   4.4
  8750   6.7  44.1  280  17  9   5.3   2.9 |   7.0  44.6  295   9  5  10.8   5.9
  8500   7.1  44.8  280  16  8   5.0   2.7 |   7.8  46.0  295   9  5  10.1   5.5
  8250   7.4  45.3  280  15  8   6.0   3.3 |   8.6  47.5  295   9  4  10.3   5.7
  8000   7.9  46.2  280  14  7   7.5   4.1 |   9.3  48.7  295   9  4  10.3   5.7
  7750   8.5  47.3  280  12  6   7.8   4.3 |  10.1  50.2  295   9  4  10.2   5.6
  7500   9.0  48.2  280  11  6   7.8   4.3 |  10.8  51.4  295   9  4  10.1   5.6
  7250   9.6  49.3  280  10  5   7.8   4.3 |  11.6  52.9  295   8  4   9.8   5.4
  7000  10.2  50.4  280   8  4   7.9   4.3 |  12.3  54.1  295   8  4   9.6   5.3
  6750  10.8  51.4  285   7  3   7.9   4.3 |  13.1  55.6  300   8  4  10.5   5.8
  6500  11.4  52.5  285   5  3   8.5   4.7 |  13.9  57.0  300   8  4  11.0   6.0
  6250  12.1  53.8  285   4  2   9.7   5.3 |  14.7  58.5  300   8  4  10.9   6.0
  6000  12.8  55.0  285   3  2   9.9   5.4 |  15.5  59.9  300   8  4  10.5   5.8
  5750  13.5  56.3  285   3  1  10.6   5.8 |  16.3  61.3  300   8  4  12.3   6.8
  5500  14.5  58.1  285   2  1  15.2   8.3 |  17.5  63.5  300   7  4  22.4  12.3

           04/19/2017 at 1500 MDT          |       04/19/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +2.2        | CAPE...     0.0    LI...       +2.5
CINH...     0.0    K Index...  -0.6        | CINH...     0.0    K Index... +10.4
                                           |
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 -61.5 -78.7  250  33 17   2.2   1.2 | -59.8 -75.6  240  30 15   1.6   0.9
 45000 -58.1 -72.6  250  50 26   2.6   1.4 | -57.5 -71.5  250  50 26   1.9   1.0
 40000 -54.0 -65.2  255  58 30   2.6   1.4 | -54.6 -66.3  255  56 29   1.9   1.0
 38000 -52.0 -61.6  255  57 30   3.6   2.0 | -52.4 -62.3  255  57 29   4.3   2.3
 36000 -49.9 -57.8  255  56 29   3.6   2.0 | -49.8 -57.6  255  56 29   4.3   2.3
 34000 -47.3 -53.1  255  53 27   5.4   3.0 | -47.4 -53.3  255  55 28   3.8   2.1
 32000 -44.1 -47.4  255  47 24   5.4   3.0 | -45.1 -49.2  255  50 26   3.8   2.1
 30000 -40.6 -41.1  255  43 22   6.8   3.7 | -42.3 -44.1  255  45 23   6.7   3.7
 29000 -38.5 -37.3  255  42 21   6.8   3.7 | -39.7 -39.5  255  42 22   6.8   3.7
 28000 -36.0 -32.8  260  40 21   6.8   3.7 | -37.7 -35.9  255  40 20   6.8   3.7
 27000 -33.9 -29.0  260  38 20   7.6   4.2 | -35.6 -32.1  255  37 19   7.4   4.0
 26000 -31.6 -24.9  260  35 18   7.6   4.1 | -33.4 -28.1  255  33 17   7.3   4.0
 25000 -29.4 -20.9  260  32 17   7.6   4.1 | -31.2 -24.2  255  29 15   7.3   4.0
 24000 -27.1 -16.8  260  29 15   8.7   4.8 | -29.0 -20.2  250  26 13   9.0   4.9
 23000 -24.5 -12.1  255  27 14   8.7   4.8 | -26.2 -15.2  245  24 13   9.2   5.0
 22000 -21.8  -7.2  255  25 13   8.7   4.8 | -23.4 -10.1  245  23 12   9.2   5.0
 21000 -19.5  -3.1  255  23 12   6.1   3.3 | -20.9  -5.6  240  22 11   6.9   3.8
 20000 -17.6   0.3  250  21 11   6.3   3.5 | -18.8  -1.8  245  20 10   7.1   3.9
 19500 -16.7   1.9  250  21 11   6.3   3.5 | -17.7   0.1  245  20 10   7.1   3.9
 19000 -15.7   3.7  250  20 10   6.2   3.4 | -16.6   2.1  245  19 10   7.2   4.0
 18500 -14.7   5.5  250  19 10   7.9   4.3 | -15.6   3.9  245  18  9   6.2   3.4
 18000 -13.5   7.7  250  19 10   7.8   4.3 | -14.7   5.5  240  16  8   6.2   3.4
 17500 -12.3   9.9  255  19 10   7.3   4.0 | -13.8   7.2  235  15  8   6.5   3.6
 17000 -11.4  11.5  250  18  9   6.4   3.5 | -12.8   9.0  240  14  7   7.0   3.8
 16500 -10.4  13.3  250  17  9   6.5   3.5 | -11.8  10.8  250  14  7   7.1   3.9
 16000  -9.5  14.9  250  16  8   6.3   3.4 | -10.3  13.5  250  13  7   6.6   3.6
 15500  -8.5  16.7  250  14  7   6.3   3.5 |  -9.3  15.3  250  13  7   6.7   3.7
 15000  -7.6  18.3  250  13  7   7.1   3.9 |  -8.3  17.1  250  13  7   7.5   4.1
 14500  -6.0  21.2  250  12  6   7.3   4.0 |  -7.2  19.0  255  13  7   7.5   4.1
 14000  -4.9  23.2  250  12  6   8.0   4.4 |  -6.2  20.8  260  12  6   6.7   3.7
 13500  -3.7  25.3  255  11  6   8.0   4.4 |  -5.2  22.6  265  11  6   6.7   3.7
 13000  -2.5  27.5  260  12  6   7.7   4.2 |  -4.2  24.4  270  11  6   7.5   4.1
 12500  -1.4  29.5  260  13  7   7.8   4.3 |  -3.1  26.4  275  10  5   7.4   4.1
 12000  -0.3  31.5  265  14  7   6.3   3.4 |  -1.9  28.6  280  10  5   9.1   5.0
 11500   0.5  32.9  270  12  6   6.2   3.4 |  -0.5  31.1  280   9  5   9.3   5.1
 11000   1.5  34.7  275  11  6   9.3   5.1 |   0.8  33.4  285   9  5   8.4   4.6
 10500   2.9  37.2  280  11  6  10.5   5.7 |   2.0  35.6  295   8  4   8.8   4.8
 10250   3.6  38.5  280  11  6   6.8   3.7 |   2.6  36.7  300   8  4   6.3   3.5
 10000   4.0  39.2  280  11  6   7.9   4.3 |   3.0  37.4  305   8  4   8.1   4.4
  9750   4.8  40.6  285  11  5  12.2   6.7 |   3.9  39.0  305   8  4  11.7   6.4
  9500   5.7  42.3  285  10  5  11.8   6.5 |   4.7  40.5  305   8  4  11.1   6.1
  9250   6.5  43.7  285  10  5   9.0   4.9 |   5.5  41.9  305   8  4  10.0   5.5
  9000   7.1  44.8  285  10  5   8.2   4.5 |   6.2  43.2  305   8  4   9.5   5.2
  8750   7.8  46.0  290  10  5  10.9   6.0 |   7.0  44.6  305   8  4  10.7   5.9
  8500   8.6  47.5  290  10  5  10.0   5.5 |   7.7  45.9  310   8  4  10.4   5.7
  8250   9.4  48.9  290  10  5  10.9   6.0 |   8.5  47.3  310   8  4  10.2   5.6
  8000  10.2  50.4  290  10  5  10.7   5.9 |   9.3  48.7  310   8  4   9.8   5.4
  7750  10.9  51.6  290  10  5   9.3   5.1 |  10.0  50.0  310   8  4   9.2   5.1
  7500  11.6  52.9  290  10  5   9.3   5.1 |  10.7  51.3  310   8  4   9.5   5.2
  7250  12.4  54.3  290  10  5  10.3   5.7 |  11.4  52.5  310   8  4  10.6   5.8
  7000  13.1  55.6  290  10  5  10.8   5.9 |  12.2  54.0  310   8  4  10.9   6.0
  6750  13.9  57.0  290  10  5   9.6   5.3 |  13.0  55.4  315   8  4   9.2   5.0
  6500  14.6  58.3  290  10  5  10.2   5.6 |  13.6  56.5  315   8  4   9.6   5.2
  6250  15.5  59.9  290   9  5  12.0   6.6 |  14.5  58.1  315   8  4  11.2   6.1
  6000  16.3  61.3  290   9  5  11.1   6.1 |  15.3  59.5  315   8  4  10.4   5.7
  5750  17.2  63.0  295   9  5  13.2   7.3 |  16.0  60.8  315   8  4  11.1   6.1
  5500  18.5  65.3  295   9  4  22.7  12.5 |  17.0  62.6  315   7  4  15.1   8.3
________________________________________________________________________________

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.

CINH (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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