Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 060109
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1809 MST Friday, February 5, 2016

This forecast is for Saturday, February 6, 2016:

If the trigger temperature of 47.9 F/8.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 285 ft/min (1.4 m/s)
   Maximum height of thermals.................. 9369 ft MSL (4062 ft AGL)

Forecast maximum temperature................... 48.0 F/9.3 C
Time of trigger temperature.................... 1345 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7256 ft MSL (1949 ft AGL)
Thermal soaring outlook for Sunday 02/07....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 11955 ft MSL (6648 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 16881 ft MSL (11574 ft AGL)
Wave soaring outlook for Sunday 02/07.......... Fair

Remarks... None

Sunrise/Sunset.................... 07:02:43 / 17:23:23 MST
Total possible sunshine........... 10 hr 20 min 41 sec (620 min 41 sec)
Altitude of sun at 12:13:25 MST... 34.67 degrees

Upper air data from numerical model forecast valid on 02/06/2016 at 0500 MST

Freezing level.................. 7278 ft MSL (1971 ft AGL)
Additional freezing level....... 7777 ft MSL (2470 ft AGL)
Convective condensation level... 19861 ft MSL (14554 ft AGL)
Lifted condensation level....... 14357 ft MSL (9050 ft AGL)
Lifted index.................... +11.5
K index......................... -13.5

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  -57.7 -71.9   305   26   14  -1.2  -0.6      M     M       M      M    M
 45000  -59.5 -75.1   305   27   14  -0.9  -0.5      M     M       M      M    M
 40000  -65.7 -86.3   320   47   24  -4.3  -2.4      M     M       M      M    M
 38000  -65.4 -85.7   325   53   27   7.4   4.0      M     M       M      M    M
 36000  -61.0 -77.8   320   54   28   7.3   4.0      M     M       M      M    M
 34000  -56.5 -69.7   320   54   28   8.6   4.7      M     M       M      M    M
 32000  -50.8 -59.4   325   48   25   8.5   4.7      M     M       M      M    M
 30000  -45.6 -50.1   335   43   22   9.1   5.0   30.1  86.2    15.9      M    M
 29000  -42.9 -45.2   335   40   21   9.1   5.0   29.8  85.6    15.9      M    M
 28000  -40.1 -40.2   340   38   20   9.1   5.0   29.5  85.2    15.9      M    M
 27000  -37.5 -35.5   345   36   18   8.2   4.5   29.3  84.8    15.9      M    M
 26000  -35.1 -31.2   340   35   18   7.9   4.4   28.5  83.4    15.5      M    M
 25000  -32.7 -26.9   340   33   17   7.9   4.4   27.9  82.1    15.1      M    M
 24000  -30.3 -22.5   340   32   17   7.8   4.3   27.3  81.1    14.9      M    M
 23000  -28.0 -18.4   340   32   16   7.6   4.2   26.4  79.5    14.3      M    M
 22000  -25.8 -14.4   335   31   16   7.6   4.2   25.6  78.1    13.8      M    M
 21000  -23.5 -10.3   335   30   16   8.0   4.4   24.9  76.9    13.4      M    M
 20000  -21.1  -6.0   340   29   15   8.0   4.4   24.2  75.6    13.0      M    M
 19500  -19.9  -3.8   340   29   15   8.0   4.4   23.9  75.1    12.8      M    M
 19000  -18.7  -1.7   340   28   14   8.0   4.4   23.7  74.6    12.6      M    M
 18500  -17.5   0.5   340   27   14   7.7   4.2   23.4  74.1    12.5      M    M
 18000  -16.4   2.5   345   26   13   7.5   4.1   23.0  73.4    12.2      M    M
 17500  -15.2   4.6   345   24   12   7.5   4.1   22.6  72.7    11.9      M    M
 17000  -13.5   7.7   340   22   12   7.7   4.2   22.1  71.7    11.6      M    M
 16500  -12.4   9.7   340   22   11   7.3   4.0   21.7  71.1    11.3      M    M
 16000  -11.4  11.5   340   21   11   6.4   3.5   21.2  70.2    10.9      M    M
 15500  -10.4  13.3   335   21   11   6.4   3.5   20.6  69.1    10.4      M    M
 15000   -9.5  14.9   335   21   11   6.1   3.3   20.0  68.1     9.9      M    M
 14500   -8.6  16.5   330   20   11   6.2   3.4   19.4  67.0     9.4      M    M
 14000   -7.7  18.1   330   20   10   5.3   2.9   18.8  65.8     8.9      M    M
 13500   -7.0  19.4   330   20   10   5.3   2.9   18.0  64.5     8.3      M    M
 13000   -6.2  20.8   325   19   10   4.2   2.3   17.3  63.1     7.6      M    M
 12500   -5.6  21.9   320   17    9   4.1   2.2   16.3  61.4     6.7      M    M
 12000   -5.1  22.8   310   16    8   2.4   1.3   15.3  59.6     5.8      M    M
 11500   -4.8  23.4   305   15    8   2.1   1.1   14.1  57.3     4.7      M    M
 11000   -4.6  23.7   295   14    7   0.9   0.5   12.8  55.0     3.5      M    M
 10500   -4.5  23.9   290   12    6   0.7   0.4   11.3  52.4     2.1      M    M
 10250   -4.5  23.9   285   11    5   0.5   0.3   10.6  51.1     1.4      M    M
 10000   -4.4  24.1   280   10    5   2.2   1.2    9.9  49.8     0.8      M    M
  9750   -4.1  24.6   275   10    5   5.9   3.2    9.5  49.0     0.3      M    M
  9500   -3.6  25.5   275    9    4   7.4   4.0    9.2  48.6     0.1      M    M
  9250   -3.1  26.4   265    8    4   6.2   3.4    9.0  48.2    -0.1    274  1.4
  9000   -2.7  27.1   270    8    4   5.0   2.7    8.7  47.6    -0.4    254  1.3
  8750   -2.2  28.0   270    8    4   8.7   4.8    8.4  47.1    -0.7    233  1.2
  8500   -1.4  29.5   275    9    4  10.5   5.8    8.5  47.3    -0.7    202  1.0
  8250   -0.8  30.6   285   10    5   6.6   3.6    8.4  47.1    -0.8    175  0.9
  8000   -0.4  31.3   295   12    6   5.0   2.8    8.0  46.5    -1.1    156  0.8
  7750    0.0  32.0   300   14    7   6.1   3.4    7.7  45.9    -1.4    136  0.7
  7500    0.3  32.5   305   17    9  -0.0  -0.0    7.3  45.2    -1.8    119  0.6
  7250   -0.0  32.0   300   19   10  -6.0  -3.3    6.2  43.2    -2.9    122  0.6
  7000   -0.4  31.3   300   22   11  -4.8  -2.7    5.1  41.1    -4.0    127  0.6
  6750   -0.8  30.6   295   24   13  -6.1  -3.3    3.9  39.1    -5.2    131  0.7
  6500   -1.3  29.7   290   25   13  -6.3  -3.5    2.7  36.8    -6.4    139  0.7
  6250   -1.7  28.9   285   21   11  -4.0  -2.2    1.5  34.8    -7.6    143  0.7
  6000   -2.1  28.2   280   17    9  -8.9  -4.9    0.4  32.7    -8.7    148  0.8
  5750   -3.4  25.9   265   14    7 -29.2 -16.0   -1.7  29.0   -10.8    180  0.9
  5500   -6.4  20.5   245    9    5 -48.4 -26.5   -5.4  22.3   -14.6    263  1.3

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

           02/06/2016 at 0800 MST          |       02/06/2016 at 1100 MST
                                           |
K index... -9.4  LI... +7.6                | K index... -3.7  LI... +7.7
CAPE... 0.0  CIN... -0.6                   | 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 -56.7 -70.1  305  29 15  -0.6  -0.3 | -56.8 -70.2  305  29 15  -0.2  -0.1
 45000 -57.6 -71.7  300  34 17  -0.1  -0.1 | -57.0 -70.6  310  41 21   0.3   0.2
 40000 -64.9 -84.8  305  45 23  -5.2  -2.8 | -63.4 -82.1  295  52 27  -4.5  -2.4
 38000 -65.1 -85.2  305  47 24   6.8   3.8 | -63.7 -82.7  290  54 28   5.7   3.1
 36000 -61.0 -77.8  305  47 24   6.8   3.7 | -59.9 -75.8  290  50 26   5.6   3.1
 34000 -56.1 -69.0  305  46 24   8.5   4.7 | -56.1 -69.0  285  46 24   8.2   4.5
 32000 -51.0 -59.8  305  43 22   8.6   4.7 | -51.2 -60.2  290  42 22   8.2   4.5
 30000 -45.8 -50.4  305  39 20   8.7   4.8 | -46.2 -51.2  295  38 20   8.9   4.9
 29000 -43.2 -45.8  305  37 19   8.7   4.7 | -43.5 -46.3  295  37 19   9.0   4.9
 28000 -40.6 -41.1  305  35 18   8.7   4.8 | -40.8 -41.4  295  35 18   9.0   4.9
 27000 -38.0 -36.4  300  33 17   8.7   4.8 | -38.1 -36.6  300  34 17   8.8   4.8
 26000 -35.4 -31.7  305  32 16   8.8   4.8 | -35.5 -31.9  300  33 17   8.8   4.8
 25000 -32.7 -26.9  305  31 16   8.8   4.8 | -32.9 -27.2  300  32 17   8.8   4.8
 24000 -30.1 -22.2  310  29 15   8.3   4.6 | -30.2 -22.4  305  32 16   8.3   4.6
 23000 -27.7 -17.9  310  28 14   7.9   4.4 | -27.9 -18.2  305  31 16   7.7   4.2
 22000 -25.4 -13.7  310  26 14   7.9   4.4 | -25.6 -14.1  310  30 15   7.7   4.2
 21000 -23.0  -9.4  310  25 13   7.5   4.1 | -23.3  -9.9  310  29 15   7.8   4.3
 20000 -20.8  -5.4  305  23 12   7.5   4.1 | -20.9  -5.6  310  28 14   7.9   4.3
 19500 -19.7  -3.5  305  23 12   7.5   4.1 | -19.8  -3.6  310  27 14   7.9   4.3
 19000 -18.6  -1.5  300  22 11   7.4   4.1 | -18.6  -1.5  315  26 14   7.9   4.3
 18500 -17.4   0.7  300  21 11   7.9   4.4 | -16.8   1.8  315  26 13   7.8   4.3
 18000 -16.2   2.8  300  21 11   8.1   4.5 | -15.7   3.7  315  25 13   7.8   4.3
 17500 -15.0   5.0  300  20 10   8.1   4.4 | -14.5   5.9  315  25 13   7.5   4.1
 17000 -13.2   8.2  305  21 11   7.7   4.2 | -13.4   7.9  310  24 12   7.3   4.0
 16500 -12.1  10.2  305  21 11   7.3   4.0 | -12.3   9.9  310  23 12   7.0   3.9
 16000 -11.1  12.0  305  21 11   6.5   3.6 | -11.3  11.7  305  22 11   6.2   3.4
 15500 -10.1  13.8  305  20 10   6.5   3.6 | -10.4  13.3  305  21 11   6.3   3.5
 15000  -9.3  15.3  300  19 10   4.8   2.6 |  -9.6  14.7  305  20 10   4.9   2.7
 14500  -8.5  16.7  300  18  9   4.9   2.7 |  -8.8  16.2  305  18  9   5.2   2.8
 14000  -7.8  18.0  295  17  9   5.5   3.0 |  -8.2  17.2  305  17  9   3.3   1.8
 13500  -7.0  19.4  295  16  8   5.5   3.0 |  -7.7  18.1  315  15  8   3.2   1.8
 13000  -6.2  20.8  295  15  8   5.2   2.9 |  -7.2  19.0  325  14  7   4.3   2.3
 12500  -5.4  22.3  300  15  8   5.3   2.9 |  -6.5  20.3  330  14  7   4.4   2.4
 12000  -4.7  23.5  305  15  8   3.6   2.0 |  -5.8  21.6  335  13  7   5.2   2.9
 11500  -4.2  24.4  310  14  7   3.3   1.8 |  -5.0  23.0  340  12  6   5.4   3.0
 11000  -3.8  25.2  315  14  7   2.2   1.2 |  -4.2  24.4  340  10  5   5.7   3.1
 10500  -3.5  25.7  315  13  7   2.2   1.2 |  -3.3  26.1  335   9  5   6.3   3.5
 10250  -3.4  25.9  315  12  6   1.1   0.6 |  -2.9  26.8  335   8  4   3.6   2.0
 10000  -3.3  26.1  315  12  6   1.0   0.6 |  -2.7  27.1  330   8  4   3.8   2.1
  9750  -3.2  26.2  315  12  6   3.4   1.9 |  -2.2  28.0  330   8  4   8.2   4.5
  9500  -2.9  26.8  315  11  6   3.9   2.2 |  -1.6  29.1  330   8  4   9.1   5.0
  9250  -2.6  27.3  315  11  6   4.5   2.5 |  -0.9  30.4  330   9  4   7.5   4.1
  9000  -2.2  28.0  320  11  6   5.3   2.9 |  -0.5  31.1  325   9  5   6.4   3.5
  8750  -1.8  28.8  320  12  6   7.0   3.9 |   0.1  32.2  325  10  5   9.3   5.1
  8500  -1.2  29.8  320  12  6   8.5   4.7 |   0.9  33.6  325  11  6  10.3   5.6
  8250  -0.6  30.9  325  13  7   8.1   4.4 |   1.6  34.9  325  13  6   8.3   4.5
  8000   0.0  32.0  320  14  7   7.9   4.4 |   2.1  35.8  320  14  7   7.6   4.2
  7750   0.6  33.1  320  16  8   8.8   4.9 |   2.7  36.9  320  16  8   7.5   4.1
  7500   1.1  34.0  320  18  9   1.9   1.0 |   3.1  37.6  315  18  9   0.1   0.1
  7250   0.9  33.6  315  20 10  -5.2  -2.8 |   2.8  37.0  305  20 10  -5.7  -3.1
  7000   0.5  32.9  305  22 11  -3.7  -2.0 |   2.3  36.1  300  22 11  -4.9  -2.7
  6750   0.2  32.4  300  24 12  -5.6  -3.1 |   1.9  35.4  295  24 12  -4.9  -2.7
  6500  -0.3  31.5  295  24 13  -5.4  -3.0 |   1.7  35.1  285  23 12  -0.7  -0.4
  6250  -0.5  31.1  290  20 11  -1.6  -0.9 |   1.8  35.2  285  20 10   2.9   1.6
  6000  -0.8  30.6  285  17  9  -8.6  -4.7 |   1.9  35.4  280  16  8  -0.3  -0.2
  5750  -2.2  28.0  270  13  7 -31.9 -17.5 |   1.6  34.9  275  12  6  -5.9  -3.2
  5500  -5.4  22.3  245   8  4 -50.4 -27.6 |   1.0  33.8  260   8  4  -8.2  -4.5

           02/06/2016 at 1400 MST          |       02/06/2016 at 1700 MST
                                           |
K index... +4.9  LI... +6.6                | K index... +5.0  LI... +4.6
CAPE... 0.0  CIN... -0.1                   | 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 -56.6 -69.9  300  36 19   0.6   0.3 | -55.8 -68.4  290  40 21   0.3   0.1
 45000 -55.8 -68.4  295  55 28   0.9   0.5 | -55.4 -67.7  290  57 29   0.4   0.2
 40000 -62.5 -80.5  285  56 29  -4.6  -2.5 | -60.4 -76.7  285  61 31  -3.5  -1.9
 38000 -63.0 -81.4  285  55 28   3.9   2.1 | -61.1 -78.0  285  60 31   1.9   1.0
 36000 -60.7 -77.3  290  52 27   3.9   2.1 | -60.0 -76.0  285  55 28   1.9   1.0
 34000 -58.0 -72.4  300  50 26   9.6   5.3 | -58.4 -73.1  280  51 26   9.6   5.3
 32000 -52.6 -62.7  300  48 25   9.0   5.0 | -53.0 -63.4  285  50 25   9.1   5.0
 30000 -47.1 -52.8  295  46 24   9.2   5.0 | -47.5 -53.5  285  48 25   9.1   5.0
 29000 -44.4 -47.9  295  44 22   9.2   5.0 | -44.8 -48.6  285  47 24   9.1   5.0
 28000 -41.0 -41.8  300  41 21   9.2   5.0 | -41.3 -42.3  290  46 24   9.1   5.0
 27000 -38.2 -36.8  300  38 20   9.2   5.1 | -38.7 -37.7  290  46 23   8.1   4.4
 26000 -35.5 -31.9  295  35 18   9.2   5.1 | -36.4 -33.5  290  42 22   7.7   4.2
 25000 -32.7 -26.9  290  31 16   9.2   5.1 | -34.1 -29.4  290  39 20   7.7   4.2
 24000 -30.0 -22.0  285  28 14   8.5   4.6 | -31.8 -25.2  290  36 18   7.9   4.4
 23000 -27.6 -17.7  295  27 14   8.0   4.4 | -29.3 -20.7  290  31 16   8.2   4.5
 22000 -25.2 -13.4  305  28 14   8.0   4.4 | -26.9 -16.4  290  26 14   8.2   4.5
 21000 -22.9  -9.2  315  28 14   7.5   4.1 | -24.5 -12.1  290  22 11   7.3   4.0
 20000 -20.6  -5.1  320  27 14   7.5   4.1 | -22.3  -8.1  300  20 10   7.3   4.0
 19500 -19.5  -3.1  320  27 14   7.5   4.1 | -21.3  -6.3  310  19 10   7.3   4.0
 19000 -18.4  -1.1  325  26 13   7.6   4.2 | -20.2  -4.4  315  18  9   7.3   4.0
 18500 -17.3   0.9  325  26 13   7.3   4.0 | -19.1  -2.4  320  18  9   7.2   3.9
 18000 -16.2   2.8  325  26 13   7.2   4.0 | -18.0  -0.4  325  18  9   7.1   3.9
 17500 -15.2   4.6  320  25 13   7.0   3.9 | -17.0   1.4  330  18  9   7.0   3.9
 17000 -14.2   6.4  320  25 13   6.1   3.3 | -16.0   3.2  335  19 10   6.5   3.6
 16500 -13.3   8.1  315  24 13   6.2   3.4 | -15.0   5.0  340  19 10   6.5   3.6
 16000 -12.5   9.5  315  24 12   5.2   2.9 | -14.0   6.8  345  20 10   6.9   3.8
 15500 -11.7  10.9  310  23 12   5.2   2.9 | -13.0   8.6  345  20 10   6.9   3.8
 15000 -10.5  13.1  310  21 11   5.1   2.8 | -11.5  11.3  350  19 10   6.8   3.7
 14500  -9.8  14.4  310  19 10   5.1   2.8 | -10.5  13.1  350  19 10   6.6   3.6
 14000  -9.0  15.8  310  17  9   5.4   3.0 |  -9.4  15.1  355  19 10   8.4   4.6
 13500  -8.2  17.2  315  16  8   5.4   2.9 |  -8.1  17.4  355  19 10   8.2   4.5
 13000  -7.4  18.7  320  14  7   6.0   3.3 |  -6.9  19.6  360  20 10   8.8   4.8
 12500  -6.4  20.5  325  14  7   6.0   3.3 |  -5.5  22.1  360  21 11   8.8   4.8
 12000  -5.5  22.1  330  13  7   7.2   4.0 |  -4.2  24.4  360  22 11   8.3   4.6
 11500  -4.4  24.1  330  12  6   7.3   4.0 |  -3.0  26.6  360  22 11   8.3   4.6
 11000  -3.2  26.2  330  12  6   8.5   4.7 |  -1.8  28.8  360  22 11   7.4   4.1
 10500  -1.9  28.6  330  12  6   9.7   5.3 |  -0.7  30.7  355  21 11   8.3   4.5
 10250  -1.3  29.7  330  12  6   4.6   2.5 |  -0.2  31.6  350  21 11   3.5   1.9
 10000  -1.1  30.0  330  12  6   6.2   3.4 |  -0.1  31.8  350  21 11   3.3   1.8
  9750  -0.3  31.5  330  13  7  12.4   6.8 |   0.4  32.7  350  19 10   7.8   4.3
  9500   0.6  33.1  325  15  7  11.7   6.4 |   0.9  33.6  345  18  9   6.9   3.8
  9250   1.4  34.5  325  16  8   9.0   4.9 |   1.4  34.5  340  17  9   6.2   3.4
  9000   1.9  35.4  325  18  9   5.8   3.2 |   1.8  35.2  340  17  9   5.8   3.2
  8750   2.4  36.3  320  20 10   7.1   3.9 |   2.3  36.1  340  17  9   7.6   4.2
  8500   2.9  37.2  315  23 12   6.5   3.6 |   2.9  37.2  335  18  9   7.9   4.3
  8250   3.3  37.9  315  25 13   1.3   0.7 |   3.5  38.3  335  19 10   6.5   3.6
  8000   3.2  37.8  310  27 14  -1.7  -0.9 |   3.9  39.0  325  21 11   5.4   3.0
  7750   3.0  37.4  300  29 15  -2.2  -1.2 |   4.3  39.7  320  23 12   5.9   3.2
  7500   2.8  37.0  295  29 15  -0.3  -0.1 |   4.6  40.3  315  25 13   1.7   0.9
  7250   3.0  37.4  295  27 14   3.7   2.0 |   4.5  40.1  310  25 13  -3.5  -1.9
  7000   3.3  37.9  290  24 12   4.2   2.3 |   4.2  39.6  305  26 13  -3.8  -2.1
  6750   3.5  38.3  290  21 11   2.8   1.5 |   3.8  38.8  295  27 14  -3.4  -1.8
  6500   3.6  38.5  285  18  9   2.0   1.1 |   3.7  38.7  290  25 13   0.8   0.4
  6250   3.8  38.8  280  15  8   2.2   1.2 |   3.9  39.0  290  22 11   3.1   1.7
  6000   4.0  39.2  275  12  6   3.9   2.1 |   4.0  39.2  285  19 10   3.6   2.0
  5750   4.1  39.4  265  10  5  -3.0  -1.6 |   4.2  39.6  285  16  8  -0.5  -0.3
  5500   3.1  37.6  245   6  3 -21.9 -12.0 |   3.7  38.7  275  10  5 -13.1  -7.2
________________________________________________________________________________

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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