Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 170127
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1927 MDT Wednesday, April 16, 2014

This forecast is for Thursday, April 17, 2014:

If the trigger temperature of 47.1 F/8.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 777 ft/min (3.9 m/s)
   Maximum height of thermals.................. 17066 ft MSL (11779 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 0930 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14127 ft MSL (8839 ft AGL)
Thermal soaring outlook for Friday 04/18....... Excellent

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 PVA
Potential height of wave....................... 27202 ft MSL (21915 ft AGL)
Wave soaring outlook for Friday 04/18.......... Poor

Remarks...

Sunrise/Sunset.................... 06:18:59 / 19:38:46 MDT
Total possible sunshine........... 13 hr 19 min 46 sec (799 min 46 sec)
Altitude of sun at 12:59:02 MDT... 60.88 degrees

Upper air data from numerical model forecast valid on 04/17/2014 at 0600 MDT

Freezing level.................. 7185 ft MSL (1898 ft AGL)
Convective condensation level... 10886 ft MSL (5599 ft AGL)
Lifted condensation level....... 13337 ft MSL (8050 ft AGL)
Lifted index.................... -0.5
K index......................... +8.0

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  -56.6 -69.9   300   31   16   0.9   0.5      M     M       M      M    M
 45000  -55.1 -67.2   305   41   21   1.1   0.6      M     M       M      M    M
 40000  -56.3 -69.3   320   46   24  -0.9  -0.5      M     M       M      M    M
 38000  -56.6 -69.9   325   51   26   0.4   0.2      M     M       M      M    M
 36000  -56.4 -69.5   330   62   32   0.4   0.2      M     M       M      M    M
 34000  -56.1 -69.0   335   74   38   1.7   0.9      M     M       M      M    M
 32000  -52.1 -61.8   330   73   38   6.2   3.4      M     M       M      M    M
 30000  -48.3 -54.9   330   72   37   8.8   4.8   27.5  81.4     8.1      M    M
 29000  -45.7 -50.3   330   69   36   8.5   4.7   26.8  80.3     7.7      M    M
 28000  -43.2 -45.8   330   66   34   8.5   4.7   26.3  79.4     7.4      M    M
 27000  -40.6 -41.1   330   63   32   8.5   4.7   26.0  78.8     7.2      M    M
 26000  -38.0 -36.4   325   59   31   8.7   4.8   25.5  77.9     6.9      M    M
 25000  -35.4 -31.7   325   56   29   8.7   4.8   25.1  77.2     6.7      M    M
 24000  -32.8 -27.0   325   52   27   9.0   5.0   24.8  76.6     6.5      M    M
 23000  -30.8 -23.4   320   49   25   5.7   3.1   23.6  74.5     5.6      M    M
 22000  -29.1 -20.4   315   46   23   5.7   3.2   22.1  71.8     4.4      M    M
 21000  -27.4 -17.3   315   43   22   6.1   3.4   20.8  69.4     3.4      M    M
 20000  -25.3 -13.5   310   39   20   7.1   3.9   19.7  67.4     2.5      M    M
 19500  -24.2 -11.6   310   38   19   7.1   3.9   19.2  66.6     2.1      M    M
 19000  -23.2  -9.8   310   36   19   7.1   3.9   18.8  65.8     1.7      M    M
 18500  -22.1  -7.8   310   34   18   7.1   3.9   18.4  65.1     1.4      M    M
 18000  -21.1  -6.0   310   32   17   6.7   3.7   17.9  64.2     0.9      M    M
 17500  -20.1  -4.2   310   29   15   6.7   3.7   17.3  63.2     0.5      M    M
 17000  -19.1  -2.4   305   27   14   6.4   3.5   16.8  62.2     0.0      M    M
 16500  -18.1  -0.6   305   25   13   6.4   3.5   16.2  61.2    -0.5    937  4.8
 16000  -17.2   1.0   300   24   12   6.5   3.6   15.7  60.2    -1.0    894  4.5
 15500  -15.7   3.7   300   22   12   6.7   3.7   14.9  58.8    -1.7    828  4.2
 15000  -14.7   5.5   300   22   11   6.7   3.7   14.4  57.8    -2.2    783  4.0
 14500  -13.8   7.2   300   21   11   6.7   3.7   13.8  56.9    -2.7    739  3.8
 14000  -12.7   9.1   300   21   11   7.5   4.1   13.4  56.1    -3.2    694  3.5
 13500  -11.6  11.1   300   20   10   7.9   4.3   13.1  55.5    -3.5    645  3.3
 13000  -10.4  13.3   295   19   10   7.9   4.3   12.8  55.0    -3.8    595  3.0
 12500   -9.3  15.3   295   17    9   7.9   4.3   12.5  54.5    -4.2    545  2.8
 12000   -8.1  17.4   295   15    8   7.2   3.9   12.2  53.9    -4.5    496  2.5
 11500   -7.1  19.2   290   13    7   6.5   3.6   11.6  53.0    -5.0    453  2.3
 11000   -6.2  20.8   285   12    6   6.1   3.4   11.1  52.0    -5.6    409  2.1
 10500   -5.4  22.3   280   10    5   6.2   3.4   10.5  50.9    -6.2    369  1.9
 10250   -4.9  23.2   275    9    5   4.5   2.5   10.2  50.3    -6.6    349  1.8
 10000   -4.7  23.5   270    9    5   3.7   2.0    9.7  49.5    -7.0    334  1.7
  9750   -4.3  24.3   265    9    4   5.9   3.2    9.3  48.8    -7.4    316  1.6
  9500   -3.9  25.0   260    8    4   6.8   3.7    9.1  48.3    -7.7    295  1.5
  9250   -3.4  25.9   250    7    4   6.0   3.3    8.8  47.8    -8.0    273  1.4
  9000   -3.0  26.6   245    7    4   5.2   2.8    8.5  47.2    -8.4    254  1.3
  8750   -2.6  27.3   235    7    4   5.7   3.1    8.1  46.6    -8.7    235  1.2
  8500   -2.2  28.0   230    7    4   6.5   3.5    7.8  46.1    -9.1    215  1.1
  8250   -1.7  28.9   225    7    4   5.2   2.9    7.6  45.6    -9.4    194  1.0
  8000   -1.4  29.5   220    7    3   4.2   2.3    7.2  44.9    -9.8    178  0.9
  7750   -1.1  30.0   215    6    3   5.0   2.7    6.8  44.2   -10.3    161  0.8
  7500   -0.7  30.7   210    6    3   6.3   3.5    6.4  43.6   -10.6    141  0.7
  7250   -0.2  31.6   205    6    3   8.0   4.4    6.2  43.2   -10.8    118  0.6
  7000    0.4  32.7   205    7    4   8.8   4.8    6.2  43.1   -11.0     92  0.5
  6750    1.1  34.0   205    7    4   7.8   4.3    6.1  42.9   -11.1     66  0.3
  6500    1.5  34.7   200    8    4   5.3   2.9    5.8  42.5   -11.4     44  0.2
  6250    1.8  35.2   195    7    4   3.8   2.1    5.4  41.7   -11.9     28  0.1
  6000    2.1  35.8   190    7    3   5.3   2.9    5.0  41.0   -12.3     12  0.1
  5750    2.5  36.5   185    6    3   3.0   1.6    4.6  40.3   -12.8      M    M
  5500    2.4  36.3   180    4    2  -4.9  -2.7    3.9  39.0   -13.6      M    M

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

           04/17/2014 at 0900 MDT          |       04/17/2014 at 1200 MDT
                                           |
K index... +5.7  LI... +3.9                | K index... +8.2  LI... +3.0
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.1
                                           |
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 -57.6 -71.7  305  29 15   0.5   0.3 | -57.8 -72.0  305  27 14  -0.3  -0.2
 45000 -56.8 -70.2  310  41 21   0.7   0.4 | -58.3 -72.9  315  40 21  -0.0  -0.0
 40000 -58.7 -73.7  325  55 28  -1.3  -0.7 | -62.3 -80.1  330  63 32  -2.8  -1.5
 38000 -58.9 -74.0  330  63 32   1.6   0.9 | -62.0 -79.6  330  69 36   5.8   3.2
 36000 -57.9 -72.2  335  71 37   1.6   0.9 | -58.5 -73.3  335  70 36   5.8   3.2
 34000 -56.8 -70.2  340  81 42   6.3   3.5 | -54.2 -65.6  340  71 37   8.8   4.8
 32000 -50.8 -59.4  335  77 39   8.8   4.9 | -48.9 -56.0  335  69 36   8.7   4.8
 30000 -45.7 -50.3  330  73 38   7.5   4.1 | -43.8 -46.8  330  66 34   7.8   4.3
 29000 -43.4 -46.1  330  70 36   7.6   4.2 | -41.5 -42.7  330  63 33   7.9   4.3
 28000 -41.1 -42.0  330  67 34   7.6   4.2 | -39.1 -38.4  325  60 31   7.9   4.3
 27000 -38.8 -37.8  330  64 33   7.8   4.3 | -36.7 -34.1  325  58 30   7.6   4.2
 26000 -36.3 -33.3  325  60 31   8.4   4.6 | -34.6 -30.3  320  55 29   7.3   4.0
 25000 -33.8 -28.8  325  57 29   8.4   4.6 | -32.4 -26.3  320  53 27   7.3   4.0
 24000 -31.3 -24.3  320  54 28   8.4   4.6 | -30.2 -22.4  320  51 26   7.3   4.0
 23000 -29.2 -20.6  320  51 26   6.7   3.7 | -28.1 -18.6  315  48 25   7.1   3.9
 22000 -27.2 -17.0  320  48 25   6.7   3.7 | -26.0 -14.8  315  45 23   7.1   3.9
 21000 -25.2 -13.4  320  45 23   6.3   3.4 | -23.9 -11.0  315  42 22   6.2   3.4
 20000 -23.5 -10.3  315  41 21   5.8   3.2 | -22.2  -8.0  310  39 20   5.7   3.1
 19500 -22.6  -8.7  315  39 20   5.8   3.2 | -21.4  -6.5  310  37 19   5.7   3.1
 19000 -21.7  -7.1  315  37 19   5.8   3.2 | -20.5  -4.9  310  35 18   5.7   3.1
 18500 -20.9  -5.6  315  35 18   5.9   3.2 | -19.7  -3.5  310  34 17   5.8   3.2
 18000 -20.0  -4.0  310  33 17   6.2   3.4 | -18.8  -1.8  305  32 16   5.9   3.3
 17500 -19.0  -2.2  310  32 16   6.1   3.3 | -17.9  -0.2  305  30 15   5.9   3.2
 17000 -18.0  -0.4  310  30 15   7.5   4.1 | -16.5   2.3  305  27 14   6.2   3.4
 16500 -16.9   1.6  310  28 15   7.4   4.1 | -15.6   3.9  305  25 13   6.2   3.4
 16000 -15.4   4.3  305  26 14   5.4   2.9 | -14.7   5.5  305  24 12   5.3   2.9
 15500 -14.6   5.7  305  25 13   5.5   3.0 | -14.0   6.8  305  23 12   5.3   2.9
 15000 -13.8   7.2  305  24 12   6.0   3.3 | -13.1   8.4  300  22 11   6.2   3.4
 14500 -12.9   8.8  305  23 12   6.0   3.3 | -12.2  10.0  300  22 11   6.1   3.4
 14000 -12.0  10.4  305  22 11   6.4   3.5 | -11.3  11.7  300  22 11   6.5   3.6
 13500 -11.0  12.2  300  21 11   6.4   3.5 | -10.3  13.5  295  21 11   6.5   3.6
 13000 -10.0  14.0  300  20 10   7.6   4.2 |  -9.3  15.3  295  21 11   7.4   4.1
 12500  -8.8  16.2  300  18 10   8.1   4.4 |  -8.2  17.2  290  19 10   7.7   4.2
 12000  -7.6  18.3  305  17  9   7.8   4.3 |  -7.0  19.4  290  17  9   7.8   4.3
 11500  -6.5  20.3  305  16  8   7.6   4.2 |  -5.8  21.6  290  15  8   7.9   4.3
 11000  -5.4  22.3  305  14  7   7.7   4.2 |  -4.7  23.5  290  12  6   7.4   4.1
 10500  -4.3  24.3  305  13  7   8.3   4.6 |  -3.6  25.5  285  10  5   8.1   4.5
 10250  -3.7  25.3  310  12  6   5.3   2.9 |  -3.1  26.4  285   8  4   3.6   2.0
 10000  -3.5  25.7  310  12  6   4.1   2.3 |  -2.9  26.8  285   8  4   4.8   2.7
  9750  -3.0  26.6  305  11  6   7.2   4.0 |  -2.3  27.9  285   6  3  10.0   5.5
  9500  -2.5  27.5  305  10  5   7.8   4.3 |  -1.6  29.1  285   5  3   9.2   5.0
  9250  -1.9  28.6  305   9  4   6.1   3.4 |  -0.9  30.4  280   4  2   7.3   4.0
  9000  -1.6  29.1  300   8  4   4.4   2.4 |  -0.5  31.1  265   2  1   5.7   3.1
  8750  -1.2  29.8  295   7  3   5.6   3.1 |  -0.0  32.0  240   2  1   7.9   4.3
  8500  -0.8  30.6  290   6  3   6.2   3.4 |   0.6  33.1  200   2  1   8.3   4.6
  8250  -0.4  31.3  280   5  3   5.1   2.8 |   1.1  34.0  175   2  1   7.6   4.2
  8000  -0.0  32.0  270   4  2   4.4   2.4 |   1.7  35.1  170   3  1   7.5   4.1
  7750   0.3  32.5  260   4  2   4.5   2.4 |   2.2  36.0  165   3  1   9.2   5.0
  7500   0.6  33.1  250   4  2   4.5   2.4 |   2.9  37.2  160   3  1  10.2   5.6
  7250   0.9  33.6  245   3  2   4.8   2.6 |   3.7  38.7  160   3  1  10.0   5.5
  7000   1.2  34.2  240   3  2   4.7   2.6 |   4.4  39.9  160   3  1  10.1   5.5
  6750   1.6  34.9  230   3  1   5.3   2.9 |   5.2  41.4  160   3  1   9.5   5.2
  6500   2.0  35.6  230   2  1   8.0   4.4 |   5.9  42.6  160   2  1  10.3   5.7
  6250   2.7  36.9  225   2  1  10.0   5.5 |   6.7  44.1  160   2  1  12.0   6.6
  6000   3.4  38.1  215   2  1   8.0   4.4 |   7.6  45.7  165   2  1   9.5   5.2
  5750   4.0  39.2  210   2  1  11.0   6.0 |   8.3  46.9  165   2  1  14.0   7.7
  5500   5.1  41.2  205   2  1  20.6  11.3 |   9.9  49.8  160   2  1  27.9  15.3

           04/17/2014 at 1500 MDT          |       04/17/2014 at 1800 MDT
                                           |
K index... +12.1  LI... +3.2               | K index... +11.5  LI... +3.5
CAPE... +0.9  CIN... M                     | CAPE... 0.0  CIN... -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 -58.6 -73.5  305  28 14  -0.2  -0.1 | -60.3 -76.5  310  31 16  -0.1  -0.1
 45000 -58.8 -73.8  315  37 19   0.3   0.2 | -60.5 -76.9  310  39 20  -0.3  -0.1
 40000 -64.8 -84.6  325  61 31  -4.0  -2.2 | -65.8 -86.4  335  49 25  -3.6  -2.0
 38000 -63.3 -81.9  330  64 33   8.0   4.4 | -63.5 -82.3  335  49 25   9.1   5.0
 36000 -58.5 -73.3  330  63 32   8.0   4.4 | -58.1 -72.6  330  45 23   9.1   5.0
 34000 -53.6 -64.5  330  62 32   9.0   4.9 | -52.7 -62.9  330  43 22   8.8   4.8
 32000 -48.2 -54.8  330  62 32   9.0   4.9 | -47.4 -53.3  325  47 24   8.8   4.8
 30000 -42.9 -45.2  330  61 31   8.5   4.6 | -42.2 -44.0  320  49 25   8.3   4.6
 29000 -40.4 -40.7  330  60 31   8.5   4.7 | -39.1 -38.4  320  48 25   8.3   4.6
 28000 -37.2 -35.0  330  59 30   8.5   4.7 | -36.6 -33.9  320  47 24   8.3   4.6
 27000 -34.7 -30.5  335  58 30   7.7   4.2 | -34.1 -29.4  320  46 24   8.3   4.5
 26000 -32.4 -26.3  330  54 28   7.6   4.2 | -31.7 -25.1  320  45 23   8.3   4.5
 25000 -30.1 -22.2  325  51 26   7.6   4.2 | -29.2 -20.6  320  44 22   8.3   4.5
 24000 -27.9 -18.2  325  48 25   6.8   3.7 | -26.7 -16.1  320  42 22   7.9   4.3
 23000 -26.0 -14.8  320  45 23   6.2   3.4 | -24.4 -11.9  320  41 21   7.8   4.3
 22000 -24.2 -11.6  315  43 22   6.3   3.4 | -22.0  -7.6  320  39 20   7.9   4.3
 21000 -22.3  -8.1  315  40 21   6.5   3.6 | -19.9  -3.8  315  37 19   5.3   2.9
 20000 -20.4  -4.7  310  37 19   6.6   3.6 | -18.2  -0.8  315  36 18   5.6   3.1
 19500 -19.4  -2.9  310  36 18   6.6   3.6 | -17.4   0.7  315  35 18   5.6   3.1
 19000 -18.4  -1.1  310  35 18   6.6   3.6 | -16.6   2.1  310  34 18   5.5   3.0
 18500 -17.5   0.5  305  33 17   5.4   3.0 | -15.7   3.7  310  33 17   7.0   3.8
 18000 -16.7   1.9  305  32 16   4.9   2.7 | -14.6   5.7  310  32 17   7.2   4.0
 17500 -16.0   3.2  305  30 16   4.8   2.6 | -13.5   7.7  310  32 16   6.8   3.7
 17000 -15.3   4.5  300  29 15   4.7   2.6 | -12.7   9.1  310  31 16   5.2   2.9
 16500 -14.6   5.7  300  28 14   4.6   2.5 | -11.9  10.6  305  31 16   5.5   3.0
 16000 -13.9   7.0  300  26 14   5.4   3.0 | -11.3  11.7  305  30 16   3.3   1.8
 15500 -13.1   8.4  295  26 13   5.4   3.0 | -10.8  12.6  300  30 15   3.4   1.9
 15000 -12.3   9.9  290  25 13   6.0   3.3 | -10.3  13.5  300  29 15   4.3   2.4
 14500 -10.9  12.4  285  24 13   6.2   3.4 |  -9.2  15.4  290  28 14   4.4   2.4
 14000  -9.9  14.2  280  24 12   7.8   4.3 |  -8.3  17.1  285  27 14   8.2   4.5
 13500  -8.8  16.2  275  22 11   7.9   4.3 |  -7.1  19.2  285  26 14   8.0   4.4
 13000  -7.7  18.1  270  20 10   7.0   3.8 |  -5.9  21.4  280  25 13   8.2   4.5
 12500  -6.7  19.9  265  17  9   6.9   3.8 |  -4.7  23.5  280  22 11   8.3   4.6
 12000  -5.6  21.9  260  14  7   7.1   3.9 |  -3.6  25.5  280  19 10   7.3   4.0
 11500  -4.6  23.7  255  10  5   7.1   3.9 |  -2.5  27.5  280  15  7   7.3   4.0
 11000  -3.5  25.7  240   7  4   7.4   4.1 |  -1.5  29.3  280  11  5   6.2   3.4
 10500  -2.5  27.5  220   5  3   8.4   4.6 |  -0.7  30.7  270   7  4   6.7   3.7
 10250  -1.9  28.6  205   4  2   3.8   2.1 |  -0.3  31.5  265   5  3   3.3   1.8
 10000  -1.8  28.8  200   4  2   5.7   3.1 |  -0.1  31.8  255   4  2   5.1   2.8
  9750  -1.0  30.2  195   4  2  11.6   6.4 |   0.5  32.9  240   4  2   9.7   5.3
  9500  -0.3  31.5  190   4  2  10.4   5.7 |   1.2  34.2  220   4  2   9.0   4.9
  9250   0.5  32.9  185   4  2   9.3   5.1 |   1.8  35.2  200   4  2   7.4   4.0
  9000   1.1  34.0  180   4  2   8.8   4.8 |   2.3  36.1  195   4  2   7.5   4.1
  8750   1.9  35.4  180   4  2  10.6   5.8 |   2.9  37.2  190   4  2  10.0   5.5
  8500   2.6  36.7  180   4  2  10.4   5.7 |   3.7  38.7  190   4  2   9.8   5.4
  8250   3.4  38.1  180   4  2  10.0   5.5 |   4.4  39.9  190   3  2   9.9   5.4
  8000   4.1  39.4  180   4  2   9.9   5.4 |   5.1  41.2  190   3  2   9.8   5.4
  7750   4.9  40.8  185   4  2  10.2   5.6 |   5.9  42.6  190   3  2   9.2   5.0
  7500   5.7  42.3  185   4  2  10.3   5.6 |   6.5  43.7  190   3  2   9.5   5.2
  7250   6.4  43.5  185   4  2  10.3   5.6 |   7.3  45.1  190   3  2  10.5   5.7
  7000   7.2  45.0  185   3  2  10.2   5.6 |   8.1  46.6  190   3  2  10.5   5.8
  6750   7.9  46.2  185   3  2   9.7   5.3 |   8.8  47.8  190   3  2   9.5   5.2
  6500   8.7  47.7  185   3  2  10.4   5.7 |   9.5  49.1  190   4  2   9.8   5.4
  6250   9.5  49.1  185   3  2  11.8   6.5 |  10.3  50.5  190   3  2  11.2   6.1
  6000  10.3  50.5  190   3  2   9.6   5.3 |  11.1  52.0  190   3  2  10.0   5.5
  5750  11.1  52.0  190   3  2  13.1   7.2 |  11.8  53.2  190   3  2  10.6   5.8
  5500  12.5  54.5  185   3  2  25.5  14.0 |  12.7  54.9  190   3  2  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.

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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