Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 110031
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1831 MDT Thursday, April 10, 2014

This forecast is for Friday, April 11, 2014:

If the trigger temperature of 60.0 F/15.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 612 ft/min (3.1 m/s)
   Maximum height of thermals.................. 17481 ft MSL (12194 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 0930 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14985 ft MSL (9698 ft AGL)
Thermal soaring outlook for Saturday 04/12..... Good

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)................ Neither
Potential height of wave....................... 44909 ft MSL (39622 ft AGL)
Wave soaring outlook for Saturday 04/12........ Fair

Remarks... Upper level high pressure ridge will shift eastward over colorado
           during the next 24 hours.

Sunrise/Sunset.................... 06:27:56 / 19:32:44 MDT
Total possible sunshine........... 13 hr 4 min 47 sec (784 min 47 sec)
Altitude of sun at 13:00:29 MDT... 58.73 degrees

Upper air data from numerical model forecast valid on 04/11/2014 at 0600 MDT

Freezing level.................. 10989 ft MSL (5702 ft AGL)
Convective condensation level... 15794 ft MSL (10507 ft AGL)
Lifted condensation level....... 16803 ft MSL (11515 ft AGL)
Lifted index.................... -1.4
K index......................... +5.5

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  -60.8 -77.4   295   43   22   0.5   0.3      M     M       M      M    M
 45000  -60.1 -76.2   305   55   28  -1.8  -1.0      M     M       M      M    M
 40000  -64.1 -83.4   300   57   29  -2.7  -1.5      M     M       M      M    M
 38000  -62.2 -80.0   300   55   28   7.3   4.0      M     M       M      M    M
 36000  -57.9 -72.2   310   53   27   7.3   4.0      M     M       M      M    M
 34000  -53.3 -63.9   315   51   26   8.4   4.6      M     M       M      M    M
 32000  -48.3 -54.9   315   50   26   8.4   4.6      M     M       M      M    M
 30000  -42.6 -44.7   315   49   25   8.4   4.6   32.7  90.9     6.2      M    M
 29000  -40.1 -40.2   320   49   25   8.4   4.6   32.2  89.9     5.9      M    M
 28000  -37.5 -35.5   320   49   25   8.4   4.6   31.7  89.1     5.6      M    M
 27000  -35.0 -31.0   320   48   25   8.3   4.5   31.3  88.3     5.3      M    M
 26000  -32.5 -26.5   320   48   25   8.3   4.5   30.6  87.1     4.9      M    M
 25000  -30.1 -22.2   320   47   24   8.3   4.6   30.1  86.1     4.5      M    M
 24000  -27.6 -17.7   320   46   24   7.5   4.1   29.6  85.2     4.1      M    M
 23000  -25.4 -13.7   315   44   23   7.4   4.1   28.6  83.5     3.4      M    M
 22000  -23.2  -9.8   315   43   22   7.4   4.1   27.8  82.1     2.8      M    M
 21000  -20.9  -5.6   310   41   21   7.5   4.1   27.0  80.7     2.2      M    M
 20000  -18.7  -1.7   310   39   20   7.5   4.1   26.2  79.1     1.4      M    M
 19500  -17.6   0.3   305   38   19   7.5   4.1   25.8  78.4     1.1      M    M
 19000  -16.5   2.3   305   37   19   7.4   4.1   25.4  77.8     0.8      M    M
 18500  -15.3   4.5   305   36   18   8.3   4.6   25.1  77.2     0.5      M    M
 18000  -14.0   6.8   305   35   18   8.3   4.5   24.9  76.8     0.3      M    M
 17500  -12.8   9.0   305   33   17   7.7   4.2   24.6  76.3     0.1      M    M
 17000  -11.8  10.8   305   33   17   6.8   3.7   24.1  75.4    -0.4    977  5.0
 16500  -10.8  12.6   305   32   16   6.8   3.8   23.6  74.5    -0.8    933  4.7
 16000   -9.9  14.2   305   31   16   5.3   2.9   23.0  73.4    -1.4    891  4.5
 15500   -8.7  16.3   305   31   16   5.4   3.0   21.9  71.5    -2.4    833  4.2
 15000   -8.0  17.6   305   30   16   5.1   2.8   21.2  70.1    -3.2    796  4.0
 14500   -7.2  19.0   300   29   15   5.1   2.8   20.4  68.7    -3.9    759  3.9
 14000   -6.4  20.5   300   29   15   6.3   3.5   19.7  67.5    -4.5    719  3.7
 13500   -5.5  22.1   295   28   15   6.1   3.3   19.1  66.5    -5.1    677  3.4
 13000   -4.4  24.1   295   28   14   7.9   4.3   18.7  65.6    -5.6    632  3.2
 12500   -3.3  26.1   295   27   14   7.8   4.3   18.4  65.0    -5.9    583  3.0
 12000   -2.2  28.0   295   26   13   7.7   4.2   18.0  64.5    -6.3    534  2.7
 11500   -1.0  30.2   290   24   12   7.7   4.2   17.7  63.9    -6.7    485  2.5
 11000    0.1  32.2   290   22   12   7.8   4.3   17.4  63.3    -7.0    436  2.2
 10500    1.2  34.2   290   20   10   8.6   4.7   17.1  62.7    -7.4    388  2.0
 10250    1.8  35.2   290   19   10   4.8   2.6   16.9  62.5    -7.6    363  1.8
 10000    2.0  35.6   290   18    9   5.2   2.9   16.4  61.5    -8.1    349  1.8
  9750    2.6  36.7   290   16    8   9.1   5.0   16.3  61.3    -8.2    323  1.6
  9500    3.2  37.8   290   14    7   8.6   4.7   16.2  61.1    -8.4    297  1.5
  9250    3.8  38.8   285   12    6   6.0   3.3   16.1  60.9    -8.5    272  1.4
  9000    4.1  39.4   285   10    5   4.8   2.6   15.7  60.2    -9.0    256  1.3
  8750    4.6  40.3   280    8    4   7.3   4.0   15.4  59.7    -9.3    234  1.2
  8500    5.2  41.4   275    6    3   7.1   3.9   15.2  59.4    -9.5    211  1.1
  8250    5.7  42.3   270    4    2   6.8   3.7   15.0  59.0    -9.7    188  1.0
  8000    6.2  43.2   255    2    1   6.6   3.6   14.8  58.6   -10.0    166  0.8
  7750    6.7  44.1   220    1    0   7.4   4.1   14.5  58.2   -10.2    143  0.7
  7500    7.2  45.0   105    1    0   6.6   3.6   14.4  57.8   -10.5    119  0.6
  7250    7.6  45.7   070    2    1   5.2   2.9   14.0  57.3   -10.8     99  0.5
  7000    8.0  46.4   060    3    2   5.4   3.0   13.7  56.7   -11.2     80  0.4
  6750    8.4  47.1   055    5    3   5.0   2.7   13.4  56.1   -11.5     61  0.3
  6500    8.7  47.7   050    6    3   1.4   0.7   12.9  55.2   -12.0     46  0.2
  6250    8.6  47.5   050    4    2  -3.6  -2.0   12.1  53.7   -12.9     42  0.2
  6000    8.4  47.1   045    3    1   5.5   3.0   11.2  52.2   -13.8     38  0.2
  5750    8.8  47.8   030    2    1  -6.6  -3.6   10.9  51.6   -14.2     19  0.1
  5500    6.5  43.7   215    1    1 -54.1 -29.7    7.9  46.3   -17.2     82  0.4

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

           04/11/2014 at 0900 MDT          |       04/11/2014 at 1200 MDT
                                           |
K index... +0.9  LI... +6.1                | K index... -0.7  LI... +4.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -61.6 -78.9  295  41 21   0.3   0.2 | -62.2 -80.0  290  39 20   0.9   0.5
 45000 -61.2 -78.2  300  52 27  -1.8  -1.0 | -60.9 -77.6  295  45 23  -2.2  -1.2
 40000 -64.9 -84.8  300  51 26  -2.5  -1.4 | -65.1 -85.2  295  45 23  -2.9  -1.6
 38000 -62.5 -80.5  300  49 25   8.0   4.4 | -62.9 -81.2  290  44 23   7.7   4.2
 36000 -57.7 -71.9  300  47 24   8.0   4.4 | -58.2 -72.8  290  43 22   7.7   4.2
 34000 -52.9 -63.2  305  44 23   8.1   4.4 | -53.5 -64.3  285  41 21   8.4   4.6
 32000 -48.1 -54.6  305  43 22   8.1   4.4 | -48.4 -55.1  290  40 20   8.5   4.6
 30000 -42.6 -44.7  310  41 21   8.5   4.7 | -42.7 -44.9  290  37 19   8.5   4.7
 29000 -40.0 -40.0  310  40 21   8.5   4.7 | -40.1 -40.2  290  35 18   8.5   4.7
 28000 -37.5 -35.5  310  39 20   8.5   4.7 | -37.6 -35.7  295  34 17   8.5   4.7
 27000 -35.0 -31.0  310  39 20   8.3   4.5 | -35.0 -31.0  295  32 17   8.3   4.5
 26000 -32.5 -26.5  310  38 20   8.3   4.5 | -32.5 -26.5  295  31 16   8.3   4.5
 25000 -30.0 -22.0  305  37 19   8.3   4.5 | -30.1 -22.2  290  31 16   8.3   4.5
 24000 -27.5 -17.5  305  37 19   8.5   4.7 | -27.6 -17.7  290  30 16   8.9   4.9
 23000 -25.0 -13.0  305  36 19   8.5   4.7 | -24.9 -12.8  290  31 16   8.8   4.8
 22000 -22.4  -8.3  305  36 19   8.5   4.7 | -22.3  -8.1  290  31 16   8.8   4.8
 21000 -20.0  -4.0  305  36 19   7.6   4.2 | -19.7  -3.5  295  31 16   8.3   4.5
 20000 -17.7   0.1  305  36 19   7.7   4.2 | -17.2   1.0  295  31 16   8.3   4.6
 19500 -16.5   2.3  300  37 19   7.7   4.2 | -16.0   3.2  295  31 16   8.3   4.6
 19000 -15.4   4.3  300  37 19   7.6   4.2 | -14.7   5.5  295  31 16   8.3   4.6
 18500 -14.2   6.4  300  36 19   8.2   4.5 | -13.5   7.7  295  31 16   7.6   4.1
 18000 -13.0   8.6  305  34 18   8.1   4.4 | -12.4   9.7  295  31 16   7.6   4.2
 17500 -11.7  10.9  305  33 17   7.5   4.1 | -11.3  11.7  295  31 16   7.5   4.1
 17000 -10.7  12.7  305  32 17   7.0   3.8 | -10.2  13.6  295  30 16   7.3   4.0
 16500  -9.7  14.5  305  32 16   6.9   3.8 |  -9.1  15.6  295  30 15   7.3   4.0
 16000  -8.8  16.2  305  31 16   5.7   3.1 |  -8.0  17.6  295  29 15   7.4   4.0
 15500  -7.5  18.5  305  29 15   5.7   3.1 |  -6.4  20.5  290  29 15   7.1   3.9
 15000  -6.7  19.9  300  29 15   5.2   2.8 |  -5.4  22.3  290  28 15   6.6   3.6
 14500  -5.9  21.4  300  28 15   5.2   2.9 |  -4.4  24.1  290  28 14   6.6   3.6
 14000  -5.2  22.6  295  28 14   5.0   2.7 |  -3.4  25.9  285  28 14   6.5   3.6
 13500  -4.5  23.9  295  28 14   4.9   2.7 |  -2.5  27.5  285  27 14   6.6   3.6
 13000  -3.6  25.5  290  27 14   6.5   3.6 |  -1.6  29.1  280  27 14   5.9   3.2
 12500  -2.7  27.1  290  25 13   6.3   3.4 |  -0.7  30.7  280  26 13   6.0   3.3
 12000  -1.7  28.9  285  23 12   7.8   4.3 |   0.2  32.4  275  25 13   6.2   3.4
 11500  -0.5  31.1  280  21 11   7.9   4.3 |   1.1  34.0  275  24 12   6.1   3.3
 11000   0.6  33.1  275  19 10   7.5   4.1 |   2.1  35.8  270  22 11   7.8   4.3
 10500   1.7  35.1  265  16  8   8.4   4.6 |   3.3  37.9  265  20 10   8.4   4.6
 10250   2.3  36.1  260  15  8   3.5   1.9 |   3.8  38.8  265  19 10   5.0   2.7
 10000   2.4  36.3  260  15  8   4.7   2.6 |   4.1  39.4  265  18  9   6.3   3.4
  9750   3.0  37.4  255  14  7  10.4   5.7 |   4.8  40.6  260  16  8  10.5   5.8
  9500   3.7  38.7  245  13  7   9.2   5.0 |   5.6  42.1  255  15  8   9.8   5.4
  9250   4.4  39.9  240  13  7   7.4   4.0 |   6.2  43.2  250  14  7   7.5   4.1
  9000   4.8  40.6  240  12  6   5.7   3.1 |   6.7  44.1  250  13  7   6.1   3.4
  8750   5.3  41.5  235  12  6   6.9   3.8 |   7.2  45.0  245  12  6   7.6   4.2
  8500   5.7  42.3  230  11  6   6.4   3.5 |   7.8  46.0  235  11  6   7.1   3.9
  8250   6.2  43.2  230  10  5   4.9   2.7 |   8.2  46.8  230  10  5   6.3   3.4
  8000   6.5  43.7  225   9  5   4.2   2.3 |   8.7  47.7  215   9  5   6.0   3.3
  7750   6.8  44.2  220   8  4   4.4   2.4 |   9.1  48.4  205   9  4   5.8   3.2
  7500   7.1  44.8  210   7  3   4.4   2.4 |   9.5  49.1  195   8  4   7.4   4.1
  7250   7.4  45.3  195   6  3   4.5   2.4 |  10.1  50.2  185   8  4   9.7   5.3
  7000   7.7  45.9  175   5  3   4.5   2.4 |  10.8  51.4  180   8  4   9.8   5.4
  6750   8.1  46.6  155   5  3   5.2   2.9 |  11.5  52.7  175   7  4   9.4   5.2
  6500   8.5  47.3  145   6  3   5.1   2.8 |  12.2  54.0  175   7  4  10.2   5.6
  6250   8.8  47.8  155   6  3   4.9   2.7 |  13.0  55.4  175   7  4  11.6   6.4
  6000   9.1  48.4  160   6  3   3.7   2.1 |  13.9  57.0  175   7  3   9.7   5.3
  5750   9.4  48.9  170   6  3   5.9   3.2 |  14.6  58.3  175   7  3  13.2   7.2
  5500  10.1  50.2  180   5  3  13.8   7.6 |  16.0  60.8  175   6  3  24.7  13.6

           04/11/2014 at 1500 MDT          |       04/11/2014 at 1800 MDT
                                           |
K index... +0.2  LI... +2.8                | K index... +5.6  LI... +1.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -62.4 -80.3  290  35 18   1.6   0.9 | -62.1 -79.8  285  34 17   1.6   0.9
 45000 -60.0 -76.0  285  38 19  -1.4  -0.8 | -59.7 -75.5  285  39 20  -1.5  -0.8
 40000 -62.6 -80.7  280  46 24  -1.8  -1.0 | -62.5 -80.5  280  57 29  -2.0  -1.1
 38000 -60.9 -77.6  275  46 24   5.7   3.1 | -60.5 -76.9  275  58 30   6.7   3.7
 36000 -57.5 -71.5  270  44 23   5.7   3.1 | -56.5 -69.7  275  54 28   6.7   3.7
 34000 -53.6 -64.5  270  42 22   8.1   4.4 | -52.3 -62.1  270  50 26   7.3   4.0
 32000 -48.1 -54.6  270  39 20   8.1   4.5 | -48.0 -54.4  270  46 24   7.3   4.0
 30000 -43.1 -45.6  265  36 19   8.6   4.7 | -42.9 -45.2  265  41 21   8.1   4.4
 29000 -40.5 -40.9  265  35 18   8.6   4.7 | -40.5 -40.9  265  38 20   8.1   4.4
 28000 -38.0 -36.4  265  34 17   8.6   4.7 | -38.0 -36.4  260  36 18   8.1   4.4
 27000 -35.4 -31.7  265  33 17   8.7   4.8 | -35.6 -32.1  260  33 17   8.5   4.7
 26000 -32.8 -27.0  265  31 16   8.7   4.8 | -33.0 -27.4  255  30 16   8.5   4.6
 25000 -30.2 -22.4  260  29 15   8.7   4.8 | -30.5 -22.9  255  27 14   8.5   4.6
 24000 -27.6 -17.7  260  28 14   8.8   4.8 | -28.0 -18.4  255  25 13   8.2   4.5
 23000 -24.9 -12.8  260  26 13   8.8   4.8 | -25.5 -13.9  260  23 12   8.2   4.5
 22000 -22.3  -8.1  260  24 13   8.8   4.8 | -23.0  -9.4  265  22 11   8.3   4.5
 21000 -19.7  -3.5  265  23 12   8.5   4.6 | -20.5  -4.9  270  21 11   8.5   4.7
 20000 -17.2   1.0  270  24 13   8.5   4.7 | -18.0  -0.4  270  22 11   8.5   4.7
 19500 -15.9   3.4  275  25 13   8.5   4.7 | -16.7   1.9  275  22 11   8.5   4.7
 19000 -14.6   5.7  280  26 13   8.6   4.7 | -15.5   4.1  275  23 12   8.5   4.7
 18500 -13.4   7.9  285  27 14   7.3   4.0 | -14.2   6.4  275  23 12   8.5   4.6
 18000 -12.3   9.9  285  28 14   7.5   4.1 | -12.9   8.8  275  22 12   8.5   4.6
 17500 -11.2  11.8  285  29 15   8.0   4.4 | -11.7  10.9  280  22 11   8.4   4.6
 17000 -10.0  14.0  285  28 14   8.4   4.6 | -10.4  13.3  280  22 12   8.3   4.5
 16500  -8.7  16.3  285  27 14   8.4   4.6 |  -9.2  15.4  280  23 12   8.3   4.5
 16000  -6.9  19.6  285  27 14   8.0   4.4 |  -8.0  17.6  280  23 12   7.7   4.2
 15500  -5.7  21.7  285  28 14   7.8   4.3 |  -6.3  20.7  285  25 13   7.6   4.2
 15000  -4.6  23.7  280  28 15   7.1   3.9 |  -5.2  22.6  285  25 13   7.0   3.9
 14500  -3.6  25.5  280  29 15   7.1   3.9 |  -4.2  24.4  285  26 13   7.0   3.9
 14000  -2.5  27.5  280  29 15   6.5   3.6 |  -3.1  26.4  285  27 14   7.8   4.3
 13500  -1.6  29.1  280  28 15   6.6   3.6 |  -2.0  28.4  285  27 14   7.8   4.3
 13000  -0.6  30.9  275  28 14   6.7   3.7 |  -0.8  30.6  285  27 14   7.7   4.2
 12500   0.4  32.7  275  26 13   6.6   3.6 |   0.3  32.5  280  27 14   7.6   4.2
 12000   1.4  34.5  270  24 13   7.5   4.1 |   1.4  34.5  280  25 13   8.6   4.7
 11500   2.5  36.5  265  22 11   7.6   4.2 |   2.7  36.9  275  23 12   8.8   4.8
 11000   3.6  38.5  260  20 10   7.2   3.9 |   3.9  39.0  270  21 11   7.8   4.3
 10500   4.6  40.3  255  18  9   6.2   3.4 |   5.0  41.0  270  19 10   6.8   3.7
 10250   5.1  41.2  250  17  9  11.3   6.2 |   5.6  42.1  270  18  9  11.6   6.4
 10000   6.1  43.0  245  16  8  12.0   6.6 |   6.7  44.1  270  17  9  12.8   7.0
  9750   6.7  44.1  245  14  7   7.3   4.0 |   7.4  45.3  270  17  9   8.8   4.8
  9500   7.3  45.1  240  13  7   8.8   4.8 |   8.1  46.6  270  16  8  10.3   5.6
  9250   8.0  46.4  240  12  6   7.6   4.2 |   8.8  47.8  270  16  8   8.5   4.6
  9000   8.5  47.3  240  11  6   8.9   4.9 |   9.4  48.9  270  15  8   9.0   4.9
  8750   9.3  48.7  240  10  5  10.6   5.8 |  10.2  50.4  270  15  8  10.8   6.0
  8500  10.0  50.0  240  10  5  10.1   5.6 |  11.0  51.8  270  14  7  10.4   5.7
  8250  10.8  51.4  235   9  5  10.0   5.5 |  11.7  53.1  270  14  7  10.2   5.6
  8000  11.5  52.7  240   9  5   9.7   5.3 |  12.5  54.5  270  13  7   9.7   5.3
  7750  12.2  54.0  240   9  5   9.7   5.3 |  13.2  55.8  270  13  7   9.6   5.3
  7500  13.0  55.4  240   9  4   9.8   5.4 |  13.9  57.0  270  13  7   9.6   5.3
  7250  13.7  56.7  240   8  4  10.2   5.6 |  14.6  58.3  270  12  6   9.8   5.4
  7000  14.5  58.1  240   8  4  10.3   5.7 |  15.4  59.7  270  12  6   9.9   5.4
  6750  15.2  59.4  240   8  4   9.8   5.4 |  16.1  61.0  270  12  6   9.7   5.3
  6500  16.0  60.8  240   8  4  10.5   5.8 |  16.8  62.2  270  12  6  10.0   5.5
  6250  16.8  62.2  240   8  4  11.6   6.4 |  17.6  63.7  275  11  6  10.4   5.7
  6000  17.7  63.9  245   8  4  10.7   5.9 |  18.4  65.1  275  11  6  10.3   5.7
  5750  18.5  65.3  245   7  4  12.0   6.6 |  19.1  66.4  275  10  5  10.1   5.5
  5500  19.6  67.3  245   7  4  19.4  10.7 |  19.9  67.8  275  10  5  11.0   6.0
________________________________________________________________________________

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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