Soaring Guidance
Issued by NWS Denver/Boulder, CO

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588
UXUS97 KBOU 101301
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0601 MST Wednesday, February 10, 2016

This forecast is for Wednesday, February 10, 2016:

If the trigger temperature of 66.3 F/19.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 458 ft/min (2.3 m/s)
   Maximum height of thermals.................. 11024 ft MSL (5739 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1330 MST
Time of overdevelopment........................ 1700 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7724 ft MSL (2439 ft AGL)
Thermal soaring outlook for Thursday 02/11..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 26641 ft MSL (21356 ft AGL)
Wave soaring outlook for Thursday 02/11........ Fair

Remarks...

Sunrise/Sunset.................... 06:58:19 / 17:28:08 MST
Total possible sunshine........... 10 hr 29 min 49 sec (629 min 49 sec)
Altitude of sun at 12:13:34 MST... 35.93 degrees

Upper air data from rawinsonde observation taken on 02/10/2016 at 0500 MST

Freezing level.................. 12029 ft MSL (6744 ft AGL)
Convective condensation level... 22917 ft MSL (17632 ft AGL)
Lifted condensation level....... 20451 ft MSL (15166 ft AGL)
Lifted index.................... +5.1
K index......................... -7.1

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  -61.5 -78.7   315   62   32   2.3   1.2   96.0 204.7    43.6      M    M
 45000  -55.6 -68.1   335   60   31   7.9   4.4   81.3 178.4    37.6      M    M
 40000  -57.3 -71.1   320   61   31  -0.6  -0.3   54.7 130.4    22.8      M    M
 38000  -59.7 -75.5   325   50   26   1.0   0.6   42.3 108.2    15.1      M    M
 36000  -56.0 -68.8   330   37   19   8.7   4.8   39.2 102.6    13.4      M    M
 34000  -51.4 -60.5   330   39   20   4.3   2.4   37.5  99.4    12.5      M    M
 32000  -47.0 -52.6   335   42   22   8.5   4.7   35.4  95.7    11.3      M    M
 30000  -42.5 -44.5   335   43   22   5.9   3.2   33.8  92.8    10.4      M    M
 29000  -40.6 -41.1   335   44   23   7.9   4.3   32.3  90.2     9.4      M    M
 28000  -38.1 -36.6   335   45   23   8.4   4.6   31.7  89.1     9.0      M    M
 27000  -34.9 -30.8   330   46   24   8.4   4.6   31.1  88.0     8.7      M    M
 26000  -32.6 -26.7   330   47   24   6.5   3.5   30.5  86.8     8.3      M    M
 25000  -30.7 -23.3   330   43   22   6.6   3.6   29.3  84.7     7.4      M    M
 24000  -28.8 -19.8   330   42   22   6.6   3.6   28.0  82.4     6.4      M    M
 23000  -26.3 -15.3   335   41   21   8.4   4.6   27.4  81.3     6.0      M    M
 22000  -23.8 -10.8   335   39   20   8.4   4.6   26.9  80.5     5.7      M    M
 21000  -21.3  -6.3   335   38   19   8.4   4.6   26.4  79.5     5.3      M    M
 20000  -18.7  -1.7   340   36   19   4.6   2.5   26.0  78.7     5.0      M    M
 19500  -18.7  -1.7   340   36   19   0.1   0.1   24.3  75.8     3.6      M    M
 19000  -18.5  -1.3   335   37   19   4.4   2.4   22.8  73.1     2.4      M    M
 18500  -17.5   0.5   335   37   19   8.6   4.7   22.4  72.3     2.0      M    M
 18000  -16.2   2.8   335   37   19   8.7   4.8   22.2  71.9     1.8      M    M
 17500  -14.9   5.2   335   37   19   8.7   4.8   22.0  71.6     1.7      M    M
 17000  -13.6   7.5   340   36   19   8.7   4.8   21.8  71.3     1.5      M    M
 16500  -12.3   9.9   340   36   19   8.7   4.8   21.7  71.1     1.4      M    M
 16000  -11.0  12.2   340   36   19   8.7   4.8   21.6  70.9     1.3      M    M
 15500   -9.7  14.5   340   35   18   8.7   4.8   21.4  70.5     1.1      M    M
 15000   -8.4  16.9   340   33   17   8.7   4.8   21.2  70.2     1.0      M    M
 14500   -7.1  19.2   345   32   16   8.8   4.8   21.0  69.8     0.8      M    M
 14000   -5.8  21.6   345   30   16   8.8   4.8   20.9  69.6     0.7      M    M
 13500   -3.7  25.3   345   28   14   9.1   5.0   20.7  69.3     0.5      M    M
 13000   -2.4  27.7   345   27   14   9.1   5.0   20.6  69.1     0.4      M    M
 12500   -1.0  30.2   345   28   15   9.1   5.0   20.5  68.9     0.3      M    M
 12000    0.3  32.5   345   29   15   9.1   5.0   20.4  68.7     0.2      M    M
 11500    1.7  35.1   340   30   15   9.1   5.0   20.3  68.5     0.1      M    M
 11000    3.0  37.4   340   30   16   9.0   5.0   20.1  68.2    -0.0    447  2.3
 10500    4.4  39.9   335   31   16   8.9   4.9   20.0  68.1    -0.1    392  2.0
 10250    5.0  41.0   335   31   16   7.7   4.2   19.9  67.9    -0.2    366  1.9
 10000    5.5  41.9   335   31   16   7.1   3.9   19.7  67.5    -0.4    342  1.7
  9750    6.1  43.0   330   30   16   7.3   4.0   19.5  67.2    -0.6    319  1.6
  9500    6.6  43.9   325   30   16   7.2   4.0   19.3  66.8    -0.8    295  1.5
  9250    7.2  45.0   325   30   15   7.3   4.0   19.1  66.4    -1.0    272  1.4
  9000    7.7  45.9   320   30   16   7.1   3.9   18.9  66.1    -1.2    248  1.3
  8750    8.2  46.8   315   31   16   7.7   4.2   18.7  65.7    -1.4    224  1.1
  8500    8.8  47.8   315   32   16   5.5   3.0   18.5  65.4    -1.6    201  1.0
  8250    9.1  48.4   310   33   17   3.3   1.8   18.1  64.6    -2.0    185  0.9
  8000    9.3  48.7   310   34   17   3.8   2.1   17.6  63.7    -2.5    170  0.9
  7750    9.6  49.3   305   31   16   3.6   2.0   17.1  62.9    -3.0    154  0.8
  7500    9.9  49.8   305   29   15   3.7   2.0   16.7  62.0    -3.4    139  0.7
  7250   10.1  50.2   300   26   14   3.7   2.0   16.2  61.2    -3.9    124  0.6
  7000   10.4  50.7   295   24   12   3.8   2.1   15.8  60.4    -4.4    108  0.5
  6750   10.7  51.3   290   20   11   5.7   3.2   15.3  59.6    -4.8     91  0.5
  6500   11.2  52.2   290   17    9   7.4   4.0   15.1  59.2    -5.0     68  0.3
  6250   11.8  53.2   280   13    7   6.3   3.4   14.9  58.8    -5.2     45  0.2
  6000   12.3  54.1   270   10    5   9.0   4.9   14.7  58.5    -5.5     22  0.1
  5750   12.8  55.0   255    8    4  -0.8  -0.4   14.5  58.1    -5.7      M    M
  5500   11.0  51.8   225    6    3 -53.5 -29.4   12.0  53.7    -8.2     45  0.2

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

           02/10/2016 at 0800 MST          |       02/10/2016 at 1100 MST
                                           |
K index... -14.3  LI... +2.4               | K index... -16.1  LI... +1.8
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -62.3 -80.1  310  41 21   3.5   1.9 | -61.6 -78.9  305  36 18   3.5   1.9
 45000 -57.2 -71.0  315  56 29   0.1   0.1 | -56.6 -69.9  305  47 24  -0.8  -0.5
 40000 -56.9 -70.4  330  48 25   0.2   0.1 | -57.6 -71.7  320  39 20  -0.7  -0.4
 38000 -55.8 -68.4  325  43 22   2.7   1.5 | -56.2 -69.2  320  38 19   4.0   2.2
 36000 -54.2 -65.6  320  37 19   2.7   1.5 | -53.8 -64.8  315  38 20   4.0   2.2
 34000 -52.0 -61.6  315  35 18   6.4   3.5 | -51.2 -60.2  310  39 20   5.2   2.9
 32000 -47.6 -53.7  320  41 21   6.5   3.6 | -47.7 -53.9  310  39 20   5.2   2.9
 30000 -43.4 -46.1  320  44 23   7.5   4.1 | -44.0 -47.2  310  39 20   7.5   4.1
 29000 -41.2 -42.2  320  45 23   7.5   4.1 | -41.7 -43.1  310  39 20   7.5   4.1
 28000 -38.9 -38.0  320  45 23   7.5   4.1 | -39.5 -39.1  315  39 20   7.5   4.1
 27000 -36.6 -33.9  320  45 23   8.3   4.6 | -37.1 -34.8  315  39 20   8.5   4.7
 26000 -34.1 -29.4  320  44 23   8.3   4.6 | -34.6 -30.3  315  39 20   8.4   4.6
 25000 -31.6 -24.9  320  44 23   8.3   4.6 | -32.1 -25.8  315  38 20   8.4   4.6
 24000 -29.2 -20.6  320  44 22   8.2   4.5 | -29.6 -21.3  315  38 19   7.9   4.3
 23000 -26.7 -16.1  320  43 22   8.2   4.5 | -27.2 -17.0  315  36 19   8.0   4.4
 22000 -24.3 -11.7  320  42 22   8.2   4.5 | -24.8 -12.6  315  35 18   8.0   4.4
 21000 -21.9  -7.4  325  41 21   7.6   4.1 | -22.4  -8.3  315  34 17   8.1   4.4
 20000 -19.6  -3.3  325  39 20   7.6   4.2 | -19.9  -3.8  315  32 17   8.1   4.4
 19500 -18.5  -1.3  325  37 19   7.6   4.2 | -18.7  -1.7  315  32 16   8.1   4.4
 19000 -17.3   0.9  325  36 19   7.6   4.2 | -17.5   0.5  320  31 16   8.1   4.5
 18500 -16.2   2.8  330  35 18   7.7   4.2 | -16.3   2.7  320  30 16   8.2   4.5
 18000 -15.1   4.8  330  34 17   7.7   4.2 | -15.1   4.8  320  30 15   8.1   4.5
 17500 -13.9   7.0  330  33 17   7.9   4.4 | -13.8   7.2  320  29 15   8.7   4.8
 17000 -12.7   9.1  330  32 16   8.0   4.4 | -11.8  10.8  325  29 15   8.8   4.8
 16500 -10.9  12.4  330  30 15   8.5   4.6 | -10.5  13.1  325  29 15   8.9   4.9
 16000  -9.6  14.7  335  29 15   8.5   4.7 |  -9.2  15.4  325  28 15   8.9   4.9
 15500  -8.3  17.1  335  28 15   8.7   4.8 |  -7.9  17.8  325  28 14   9.0   5.0
 15000  -7.0  19.4  335  28 14   8.9   4.9 |  -6.5  20.3  325  28 14   9.1   5.0
 14500  -5.7  21.7  335  27 14   8.9   4.9 |  -5.1  22.8  325  28 14   9.1   5.0
 14000  -4.3  24.3  335  27 14   9.1   5.0 |  -3.8  25.2  330  28 15   9.1   5.0
 13500  -3.0  26.6  335  26 14   9.1   5.0 |  -2.4  27.7  330  28 15   9.1   5.0
 13000  -1.6  29.1  335  26 14   9.5   5.2 |  -1.1  30.0  330  29 15   8.8   4.9
 12500  -0.1  31.8  335  26 14   9.5   5.2 |   0.3  32.5  330  29 15   8.9   4.9
 12000   1.2  34.2  335  27 14   8.8   4.8 |   1.6  34.9  325  30 15   9.2   5.1
 11500   2.6  36.7  335  27 14   8.9   4.9 |   3.0  37.4  325  31 16   9.2   5.1
 11000   3.9  39.0  330  27 14   8.6   4.7 |   4.3  39.7  325  31 16   8.4   4.6
 10500   5.1  41.2  330  27 14   8.1   4.5 |   5.6  42.1  320  32 17   8.0   4.4
 10250   5.6  42.1  325  28 14   4.7   2.6 |   6.1  43.0  320  33 17   4.6   2.5
 10000   6.0  42.8  325  28 14   7.6   4.1 |   6.4  43.5  320  33 17   7.4   4.0
  9750   6.8  44.2  325  29 15  11.8   6.4 |   7.2  45.0  320  33 17  11.4   6.3
  9500   7.6  45.7  325  29 15  10.1   5.5 |   8.0  46.4  315  34 17   9.8   5.4
  9250   8.3  46.9  320  30 16   7.7   4.2 |   8.7  47.7  315  34 17   7.1   3.9
  9000   8.8  47.8  320  31 16   7.4   4.1 |   9.1  48.4  315  34 18   6.9   3.8
  8750   9.4  48.9  320  31 16   9.1   5.0 |   9.8  49.6  310  35 18   9.1   5.0
  8500  10.1  50.2  320  32 17   8.4   4.6 |  10.4  50.7  310  36 18   8.1   4.4
  8250  10.6  51.1  315  33 17   7.4   4.1 |  10.9  51.6  310  36 19   6.9   3.8
  8000  11.2  52.2  315  34 18   7.1   3.9 |  11.4  52.5  305  37 19   6.5   3.6
  7750  11.7  53.1  315  35 18   7.1   3.9 |  11.9  53.4  305  37 19   7.1   3.9
  7500  12.2  54.0  310  36 19   5.3   2.9 |  12.4  54.3  300  38 20   5.2   2.8
  7250  12.5  54.5  310  37 19   3.6   2.0 |  12.7  54.9  300  38 20   3.2   1.8
  7000  12.7  54.9  305  37 19   5.1   2.8 |  12.9  55.2  295  38 20   4.1   2.3
  6750  13.0  55.4  300  38 19   0.2   0.1 |  13.2  55.8  295  38 20   2.8   1.5
  6500  12.6  54.7  295  37 19 -10.2  -5.6 |  13.2  55.8  290  36 19  -1.7  -1.0
  6250  11.6  52.9  290  33 17 -11.7  -6.4 |  12.9  55.2  285  33 17  -0.6  -0.4
  6000  10.7  51.3  285  29 15 -15.8  -8.7 |  12.7  54.9  285  29 15  -9.5  -5.2
  5750   8.6  47.5  280  25 13 -40.9 -22.4 |  11.0  51.8  275  23 12 -28.5 -15.6
  5500   4.5  40.1  270  16  8 -66.2 -36.3 |   8.5  47.3  270  14  7 -31.0 -17.0

           02/10/2016 at 1400 MST          |       02/10/2016 at 1700 MST
                                           |
K index... -18.0  LI... +1.7               | K index... -24.6  LI... +2.0
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -1.2
                                           |
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 -61.2 -78.2  295  34 17   4.0   2.2 | -60.0 -76.0  295  39 20   4.9   2.7
 45000 -55.7 -68.3  295  39 20  -3.0  -1.7 | -53.2 -63.8  290  44 22  -6.7  -3.7
 40000 -59.7 -75.5  315  47 24  -2.7  -1.5 | -61.6 -78.9  300  62 32  -5.7  -3.1
 38000 -58.0 -72.4  315  48 25   5.9   3.2 | -60.2 -76.4  305  62 32   6.9   3.8
 36000 -54.4 -65.9  320  48 25   5.9   3.2 | -56.1 -69.0  305  56 29   6.9   3.8
 34000 -50.7 -59.3  320  48 24   6.8   3.7 | -51.9 -61.4  310  51 26   7.1   3.9
 32000 -46.1 -51.0  320  49 25   6.8   3.7 | -47.6 -53.7  315  49 25   7.1   3.9
 30000 -42.2 -44.0  315  46 24   6.1   3.4 | -42.7 -44.9  325  46 24   7.6   4.2
 29000 -40.3 -40.5  315  42 21   6.1   3.4 | -40.4 -40.7  325  44 23   7.6   4.2
 28000 -38.5 -37.3  310  38 19   6.2   3.4 | -38.1 -36.6  325  42 22   7.6   4.2
 27000 -36.5 -33.7  305  35 18   7.7   4.2 | -35.9 -32.6  325  40 20   7.4   4.0
 26000 -34.2 -29.6  305  35 18   7.6   4.2 | -33.7 -28.7  320  36 19   7.4   4.1
 25000 -31.9 -25.4  305  34 18   7.6   4.2 | -31.4 -24.5  320  33 17   7.4   4.1
 24000 -29.7 -21.5  305  34 17   7.8   4.3 | -29.2 -20.6  315  30 16   7.5   4.1
 23000 -27.3 -17.1  305  32 17   7.8   4.3 | -27.0 -16.6  315  30 15   7.5   4.1
 22000 -25.0 -13.0  310  31 16   7.8   4.3 | -24.7 -12.5  315  29 15   7.5   4.1
 21000 -22.6  -8.7  310  29 15   8.2   4.5 | -22.4  -8.3  310  28 15   8.1   4.4
 20000 -20.1  -4.2  310  28 14   8.2   4.5 | -20.0  -4.0  315  28 15   8.0   4.4
 19500 -18.9  -2.0  310  27 14   8.2   4.5 | -18.8  -1.8  315  28 14   8.0   4.4
 19000 -17.7   0.1  315  27 14   8.1   4.5 | -17.6   0.3  315  28 14   8.0   4.4
 18500 -16.4   2.5  315  26 14   9.0   4.9 | -16.3   2.7  320  28 15   8.7   4.8
 18000 -15.1   4.8  315  26 13   8.9   4.9 | -15.1   4.8  320  29 15   8.6   4.7
 17500 -13.7   7.3  320  26 13   8.8   4.9 | -13.8   7.2  320  30 15   8.6   4.7
 17000 -11.8  10.8  320  26 13   8.8   4.8 | -12.5   9.5  320  30 15   8.6   4.7
 16500 -10.4  13.3  320  26 13   9.1   5.0 | -11.2  11.8  320  30 15   8.7   4.7
 16000  -9.1  15.6  325  26 14   9.1   5.0 |  -9.2  15.4  320  31 16   8.9   4.9
 15500  -7.7  18.1  325  27 14   8.9   4.9 |  -7.9  17.8  320  31 16   8.7   4.8
 15000  -6.4  20.5  325  27 14   8.7   4.8 |  -6.6  20.1  320  32 16   8.5   4.7
 14500  -5.1  22.8  325  28 14   8.7   4.8 |  -5.3  22.5  320  33 17   8.6   4.7
 14000  -3.8  25.2  325  28 15   8.9   4.9 |  -4.0  24.8  320  33 17   8.9   4.9
 13500  -2.4  27.7  325  29 15   8.9   4.9 |  -2.7  27.1  320  34 18   8.9   4.9
 13000  -1.1  30.0  325  30 15   9.0   5.0 |  -1.4  29.5  320  35 18   8.7   4.8
 12500   0.2  32.4  325  30 15   9.0   5.0 |  -0.1  31.8  320  35 18   8.7   4.8
 12000   1.6  34.9  325  31 16   8.9   4.9 |   1.3  34.3  320  36 18   8.9   4.9
 11500   2.9  37.2  320  31 16   9.0   4.9 |   2.6  36.7  320  36 19   8.9   4.9
 11000   4.3  39.7  320  32 16   8.6   4.7 |   3.9  39.0  320  37 19   8.6   4.7
 10500   5.5  41.9  320  33 17   9.0   5.0 |   5.2  41.4  320  37 19   9.3   5.1
 10250   6.1  43.0  315  33 17   4.9   2.7 |   5.8  42.4  320  37 19   4.5   2.5
 10000   6.4  43.5  315  33 17   6.0   3.3 |   6.0  42.8  320  38 19   5.5   3.0
  9750   7.1  44.8  315  34 18  10.3   5.7 |   6.7  44.1  315  38 20  10.6   5.8
  9500   7.8  46.0  315  35 18   9.2   5.0 |   7.4  45.3  315  39 20   9.3   5.1
  9250   8.5  47.3  310  36 18   7.0   3.8 |   8.1  46.6  315  39 20   7.6   4.2
  9000   8.9  48.0  310  36 18   6.7   3.7 |   8.6  47.5  315  39 20   6.5   3.6
  8750   9.5  49.1  310  36 19   8.9   4.9 |   9.1  48.4  310  40 20   7.6   4.1
  8500  10.2  50.4  305  37 19   7.9   4.3 |   9.7  49.5  310  40 21   7.0   3.8
  8250  10.7  51.3  305  37 19   6.1   3.4 |  10.2  50.4  310  40 21   5.9   3.3
  8000  11.1  52.0  300  38 19   5.4   2.9 |  10.6  51.1  305  40 20   5.3   2.9
  7750  11.5  52.7  300  38 20   5.4   3.0 |  11.0  51.8  305  39 20   5.5   3.0
  7500  11.9  53.4  295  38 20   5.2   2.9 |  11.3  52.3  300  39 20   4.2   2.3
  7250  12.2  54.0  295  37 19   5.3   2.9 |  11.5  52.7  300  37 19   2.9   1.6
  7000  12.6  54.7  290  36 18   5.6   3.1 |  11.7  53.1  295  35 18   3.4   1.9
  6750  12.9  55.2  290  34 18   4.6   2.5 |  11.8  53.2  295  32 17   1.9   1.1
  6500  13.1  55.6  285  32 16   0.5   0.3 |  11.8  53.2  290  29 15   0.1   0.0
  6250  12.9  55.2  285  27 14  -2.7  -1.5 |  11.7  53.1  290  25 13  -1.1  -0.6
  6000  12.7  54.9  285  23 12   2.0   1.1 |  11.6  52.9  290  21 11   2.7   1.5
  5750  12.7  54.9  280  19 10  -4.9  -2.7 |  11.7  53.1  290  17  9  -5.2  -2.8
  5500  11.2  52.2  275  13  7 -30.5 -16.7 |  10.2  50.4  285  11  6 -32.0 -17.6
________________________________________________________________________________

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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