Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 111322
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0622 MST Thursday, February 11, 2016

This forecast is for Thursday, February 11, 2016:

If the trigger temperature of 62.9 F/17.2 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 49 ft/min (0.3 m/s)
   Maximum height of thermals.................. 8917 ft MSL (3632 ft AGL)

Forecast maximum temperature................... 62.0 F/17.1 C
Time of trigger temperature.................... 1400 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6901 ft MSL (1615 ft AGL)
Thermal soaring outlook for Friday 02/12....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 30331 ft MSL (25046 ft AGL)
Wave soaring outlook for Friday 02/12.......... Poor

Remarks... Moderate northwesterly flow aloft over colorado today and Friday.

Sunrise/Sunset.................... 06:57:10 / 17:29:19 MST
Total possible sunshine........... 10 hr 32 min 10 sec (632 min 10 sec)
Altitude of sun at 12:13:34 MST... 36.26 degrees

Upper air data from rawinsonde observation taken on 02/11/2016 at 0500 MST

Freezing level.................. 11343 ft MSL (6058 ft AGL)
Convective condensation level... 21692 ft MSL (16407 ft AGL)
Lifted condensation level....... 17963 ft MSL (12678 ft AGL)
Lifted index.................... +7.1
K index......................... -3.5

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  -58.4 -73.1   275   37   19   3.7   2.0  102.6 216.6    49.1      M    M
 45000  -57.7 -71.9   300   53   27   0.9   0.5   79.2 174.5    38.2      M    M
 40000  -59.9 -75.8   315   53   27   3.8   2.1   51.5 124.6    22.9      M    M
 38000  -61.8 -79.2   320   64   33   7.5   4.1   39.8 103.7    15.7      M    M
 36000  -59.3 -74.7   330   54   28   6.7   3.7   35.0  94.9    12.7      M    M
 34000  -54.7 -66.5   350   56   29   9.3   5.1   33.3  91.9    11.9      M    M
 32000  -49.4 -56.9   345   68   35   6.8   3.7   32.4  90.4    11.5      M    M
 30000  -45.2 -49.4   345   78   40   8.9   4.9   30.3  86.6    10.3      M    M
 29000  -42.5 -44.5   340   74   38   8.9   4.9   29.9  85.9    10.1      M    M
 28000  -39.8 -39.6   340   69   35   8.9   4.9   29.6  85.3    10.0      M    M
 27000  -36.6 -33.9   335   63   33   8.5   4.7   29.2  84.5     9.7      M    M
 26000  -34.1 -29.4   330   59   31   8.7   4.8   28.7  83.7     9.5      M    M
 25000  -31.2 -24.2   325   56   29   9.7   5.3   28.6  83.6     9.6      M    M
 24000  -28.5 -19.3   320   54   28   7.9   4.3   28.4  83.2     9.5      M    M
 23000  -26.0 -14.8   320   50   26   8.4   4.6   27.8  82.1     9.1      M    M
 22000  -23.5 -10.3   325   46   24   9.0   4.9   27.4  81.3     8.9      M    M
 21000  -21.1  -6.0   325   42   22   7.7   4.2   26.8  80.2     8.5      M    M
 20000  -18.8  -1.8   330   38   20   7.8   4.3   26.1  79.0     7.9      M    M
 19500  -17.6   0.3   325   37   19   8.0   4.4   25.8  78.4     7.7      M    M
 19000  -16.3   2.7   320   37   19   9.2   5.1   25.6  78.1     7.6      M    M
 18500  -15.3   4.5   320   36   19   5.5   3.0   25.1  77.2     7.2      M    M
 18000  -14.4   6.1   320   35   18   5.7   3.1   24.4  76.0     6.7      M    M
 17500  -13.4   7.9   320   34   17   7.3   4.0   23.9  75.0     6.3      M    M
 17000  -12.3   9.9   325   33   17   7.3   4.0   23.4  74.2     5.9      M    M
 16500  -11.4  11.5   325   31   16   4.7   2.6   22.9  73.2     5.4      M    M
 16000  -10.8  12.6   325   30   16   4.1   2.2   21.9  71.5     4.5      M    M
 15500  -10.2  13.6   325   30   15   6.3   3.5   21.0  69.9     3.7      M    M
 15000   -9.0  15.8   325   30   15   7.7   4.2   20.7  69.2     3.4      M    M
 14500   -7.9  17.8   330   30   15   7.8   4.3   20.4  68.7     3.2      M    M
 14000   -6.1  21.0   330   30   15   7.8   4.3   19.9  67.9     2.8      M    M
 13500   -4.9  23.2   335   28   14   7.8   4.3   19.6  67.3     2.5      M    M
 13000   -3.8  25.2   335   26   14   7.8   4.3   19.3  66.7     2.3      M    M
 12500   -2.6  27.3   330   23   12   7.8   4.3   18.9  66.1     2.0      M    M
 12000   -1.4  29.5   325   20   11   7.8   4.3   18.6  65.5     1.7      M    M
 11500   -0.2  31.6   315   17    9   8.4   4.6   18.3  65.0     1.4      M    M
 11000    1.0  33.8   305   15    8   8.3   4.6   18.1  64.6     1.2      M    M
 10500    2.3  36.1   310   15    8   8.3   4.6   17.9  64.2     1.0      M    M
 10250    2.9  37.2   315   15    8   8.4   4.6   17.8  64.0     0.9      M    M
 10000    3.5  38.3   315   16    8   8.5   4.7   17.7  63.8     0.8      M    M
  9750    4.1  39.4   315   17    9   8.6   4.7   17.6  63.6     0.7      M    M
  9500    4.8  40.6   315   18    9   8.3   4.5   17.5  63.5     0.6      M    M
  9250    5.3  41.5   315   19   10   6.0   3.3   17.3  63.2     0.4      M    M
  9000    5.7  42.3   315   20   10   4.7   2.6   16.9  62.5     0.1      M    M
  8750    6.1  43.0   310   18    9   5.1   2.8   16.6  61.8    -0.3    235  1.2
  8500    6.4  43.5   300   17    9   5.0   2.7   16.2  61.2    -0.7    217  1.1
  8250    6.8  44.2   295   16    8   5.0   2.7   15.8  60.5    -1.0    198  1.0
  8000    7.2  45.0   285   15    8   5.0   2.7   15.5  59.9    -1.4    180  0.9
  7750    7.5  45.5   280   15    8   5.0   2.7   15.1  59.2    -1.7    162  0.8
  7500    7.9  46.2   275   16    8   5.0   2.7   14.8  58.6    -2.1    143  0.7
  7250    8.2  46.8   275   16    8   5.0   2.7   14.4  57.9    -2.5    125  0.6
  7000    8.6  47.5   270   17    9   5.0   2.8   14.0  57.3    -2.8    107  0.5
  6750    9.0  48.2   265   14    7   4.9   2.7   13.7  56.6    -3.2     88  0.4
  6500    9.3  48.7   260   12    6   5.2   2.9   13.3  55.9    -3.6     70  0.4
  6250    9.7  49.5   250    9    5   4.2   2.3   12.9  55.3    -4.0     52  0.3
  6000   10.1  50.2   240    7    4   8.2   4.5   12.6  54.6    -4.4     33  0.2
  5750   10.4  50.7   215    6    3  -6.7  -3.7   12.2  54.0    -4.7     15  0.1
  5500    8.0  46.4   190    6    3 -59.9 -32.8    9.2  48.5    -7.9     80  0.4

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

           02/11/2016 at 0800 MST          |       02/11/2016 at 1100 MST
                                           |
K index... +1.1  LI... +4.1                | K index... +9.3  LI... +2.1
CAPE... 0.0  CIN... -0.0                   | 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 -60.5 -76.9  300  40 21   1.4   0.8 | -60.7 -77.3  300  41 21   1.5   0.8
 45000 -58.5 -73.3  305  50 26  -1.4  -0.8 | -58.5 -73.3  305  49 25  -1.5  -0.8
 40000 -62.5 -80.5  320  59 30  -2.6  -1.5 | -62.9 -81.2  320  57 29  -3.0  -1.6
 38000 -61.5 -78.7  325  63 32   5.1   2.8 | -62.1 -79.8  325  61 32   5.0   2.7
 36000 -58.4 -73.1  330  67 34   5.1   2.8 | -59.1 -74.4  335  66 34   5.0   2.7
 34000 -54.4 -65.9  335  69 36   8.1   4.4 | -54.8 -66.6  335  70 36   9.2   5.1
 32000 -49.5 -57.1  330  66 34   8.1   4.4 | -49.3 -56.7  335  69 36   9.2   5.0
 30000 -44.5 -48.1  325  63 33   8.9   4.9 | -43.8 -46.8  335  66 34   8.7   4.8
 29000 -41.8 -43.2  325  62 32   8.9   4.9 | -41.2 -42.2  335  64 33   8.7   4.8
 28000 -39.1 -38.4  325  61 31   8.9   4.9 | -38.6 -37.5  330  62 32   8.7   4.8
 27000 -36.5 -33.7  320  59 30   8.6   4.7 | -36.0 -32.8  330  59 30   8.2   4.5
 26000 -33.9 -29.0  320  55 29   8.6   4.7 | -33.6 -28.5  325  53 27   8.3   4.5
 25000 -31.4 -24.5  320  52 27   8.6   4.7 | -31.1 -24.0  325  48 24   8.3   4.5
 24000 -28.8 -19.8  320  48 25   7.7   4.2 | -28.7 -19.7  320  43 22   7.6   4.2
 23000 -26.5 -15.7  315  44 22   7.7   4.2 | -26.4 -15.5  320  40 20   7.6   4.2
 22000 -24.3 -11.7  315  39 20   7.7   4.2 | -24.2 -11.6  320  36 19   7.7   4.2
 21000 -22.0  -7.6  315  34 18   7.5   4.1 | -22.0  -7.6  320  33 17   6.7   3.7
 20000 -19.7  -3.5  315  31 16   7.5   4.1 | -20.0  -4.0  320  31 16   6.8   3.7
 19500 -18.6  -1.5  315  30 15   7.5   4.1 | -19.0  -2.2  315  29 15   6.8   3.7
 19000 -17.5   0.5  315  28 15   7.6   4.2 | -18.0  -0.4  315  28 14   6.8   3.7
 18500 -16.4   2.5  320  27 14   6.8   3.7 | -16.9   1.6  315  26 13   7.3   4.0
 18000 -15.4   4.3  320  25 13   6.9   3.8 | -15.8   3.6  315  24 13   7.3   4.0
 17500 -14.4   6.1  320  24 12   7.1   3.9 | -14.1   6.6  315  23 12   8.0   4.4
 17000 -12.7   9.1  325  23 12   7.3   4.0 | -13.7   7.3  315  23 12   7.9   4.3
 16500 -11.6  11.1  330  22 11   7.4   4.0 | -11.7  10.9  315  23 12   8.4   4.6
 16000 -10.5  13.1  330  21 11   7.4   4.1 | -10.5  13.1  315  23 12   8.6   4.7
 15500  -9.4  15.1  330  20 11   7.6   4.2 |  -9.2  15.4  315  22 12   9.0   4.9
 15000  -8.2  17.2  335  20 10   8.1   4.4 |  -7.8  18.0  320  23 12   9.5   5.2
 14500  -7.0  19.4  335  19 10   8.1   4.4 |  -6.3  20.7  320  24 12   9.4   5.2
 14000  -5.7  21.7  335  18  9   8.1   4.5 |  -4.9  23.2  320  25 13   9.1   5.0
 13500  -4.5  23.9  335  17  9   8.1   4.4 |  -3.6  25.5  325  25 13   9.2   5.0
 13000  -3.2  26.2  335  17  9   8.8   4.8 |  -2.2  28.0  325  26 14   8.9   4.9
 12500  -1.9  28.6  335  16  8   8.7   4.8 |  -0.9  30.4  325  27 14   9.0   5.0
 12000  -0.6  30.9  335  16  8   8.8   4.8 |   0.4  32.7  325  28 14   8.0   4.4
 11500   0.7  33.3  335  16  8   8.7   4.8 |   1.6  34.9  325  29 15   8.1   4.4
 11000   2.0  35.6  335  16  8   9.5   5.2 |   2.9  37.2  330  30 15   8.8   4.8
 10500   3.4  38.1  330  17  9  10.7   5.9 |   4.2  39.6  330  31 16   9.3   5.1
 10250   4.1  39.4  330  17  9   4.2   2.3 |   4.8  40.6  330  31 16   3.9   2.1
 10000   4.3  39.7  330  18  9   5.4   3.0 |   4.9  40.8  330  31 16   5.0   2.7
  9750   5.1  41.2  325  19 10  12.8   7.0 |   5.6  42.1  330  31 16  10.6   5.8
  9500   5.9  42.6  325  20 10  10.9   6.0 |   6.3  43.3  330  31 16   8.8   4.8
  9250   6.7  44.1  325  21 11   8.5   4.7 |   6.9  44.4  325  31 16   5.9   3.2
  9000   7.2  45.0  320  23 12   6.7   3.7 |   7.3  45.1  325  31 16   4.0   2.2
  8750   7.8  46.0  320  25 13   8.4   4.6 |   7.6  45.7  325  31 16   5.2   2.9
  8500   8.4  47.1  315  28 14   7.4   4.1 |   8.0  46.4  325  31 16   4.5   2.5
  8250   8.8  47.8  315  30 15   4.6   2.5 |   8.3  46.9  320  31 16   3.2   1.7
  8000   9.1  48.4  310  32 16   3.2   1.8 |   8.5  47.3  315  31 16   2.6   1.5
  7750   9.3  48.7  305  34 17   1.8   1.0 |   8.7  47.7  315  31 16   1.9   1.1
  7500   9.3  48.7  305  35 18  -0.7  -0.4 |   8.8  47.8  310  31 16   1.1   0.6
  7250   9.2  48.6  300  35 18  -1.7  -0.9 |   8.8  47.8  310  29 15   1.1   0.6
  7000   9.0  48.2  295  34 17  -1.4  -0.8 |   8.9  48.0  305  26 14   1.2   0.7
  6750   8.9  48.0  295  33 17  -2.2  -1.2 |   8.9  48.0  300  24 12   0.6   0.3
  6500   8.6  47.5  290  30 15  -5.1  -2.8 |   8.9  48.0  300  21 11   0.3   0.2
  6250   8.1  46.6  285  25 13  -8.9  -4.9 |   9.0  48.2  300  17  9   2.7   1.5
  6000   7.6  45.7  280  20 10  -1.1  -0.6 |   9.0  48.2  300  14  7  -3.5  -1.9
  5750   7.0  44.6  270  16  8 -28.5 -15.7 |   8.0  46.4  290  10  5 -24.0 -13.2
  5500   2.4  36.3  245  10  5 -87.4 -47.9 |   5.3  41.5  265   5  3 -39.6 -21.7

           02/11/2016 at 1400 MST          |       02/11/2016 at 1700 MST
                                           |
K index... +11.7  LI... +3.4               | K index... +11.8  LI... +3.9
CAPE... 0.0  CIN... -0.9                   | 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 -59.3 -74.7  300  42 22   1.4   0.8 | -59.4 -74.9  300  42 22   1.3   0.7
 45000 -57.3 -71.1  305  49 25  -2.2  -1.2 | -57.5 -71.5  305  52 27  -3.0  -1.7
 40000 -63.6 -82.5  320  60 31  -4.2  -2.3 | -65.2 -85.4  315  59 31  -5.2  -2.8
 38000 -62.8 -81.0  320  61 31   5.7   3.1 | -63.9 -83.0  315  61 32   7.5   4.1
 36000 -59.4 -74.9  325  60 31   5.7   3.1 | -59.4 -74.9  320  62 32   7.5   4.1
 34000 -54.8 -66.6  325  58 30   9.1   5.0 | -54.7 -66.5  320  62 32   8.8   4.8
 32000 -49.3 -56.7  325  53 27   9.1   5.0 | -48.7 -55.7  320  58 30   8.9   4.9
 30000 -43.9 -47.0  325  51 26   9.0   5.0 | -43.5 -46.3  315  54 28   8.7   4.8
 29000 -41.2 -42.2  325  50 26   9.1   5.0 | -40.8 -41.4  315  52 27   8.8   4.8
 28000 -38.4 -37.1  325  50 26   9.1   5.0 | -38.2 -36.8  315  50 26   8.8   4.8
 27000 -35.8 -32.4  325  49 25   8.6   4.7 | -35.6 -32.1  310  47 24   8.8   4.8
 26000 -33.2 -27.8  320  47 24   8.6   4.7 | -32.9 -27.2  310  44 23   8.8   4.8
 25000 -30.6 -23.1  320  45 23   8.6   4.7 | -30.3 -22.5  310  41 21   8.8   4.9
 24000 -28.1 -18.6  320  43 22   7.9   4.3 | -27.7 -17.9  305  38 20   7.6   4.2
 23000 -25.7 -14.3  320  39 20   7.9   4.3 | -25.4 -13.7  310  36 18   7.7   4.2
 22000 -23.4 -10.1  315  36 18   7.9   4.3 | -23.1  -9.6  310  34 17   7.8   4.3
 21000 -21.0  -5.8  315  34 18   7.8   4.3 | -20.8  -5.4  310  33 17   8.0   4.4
 20000 -18.7  -1.7  320  36 18   7.8   4.3 | -18.4  -1.1  320  37 19   8.0   4.4
 19500 -17.5   0.5  325  36 19   7.9   4.3 | -17.2   1.0  320  39 20   8.0   4.4
 19000 -16.4   2.5  325  37 19   8.0   4.4 | -16.0   3.2  325  41 21   8.1   4.4
 18500 -15.3   4.5  325  37 19   6.9   3.8 | -14.9   5.2  325  42 21   7.2   3.9
 18000 -13.7   7.3  325  36 18   7.0   3.8 | -13.8   7.2  325  42 22   7.3   4.0
 17500 -12.6   9.3  325  35 18   8.0   4.4 | -12.7   9.1  325  42 22   7.4   4.0
 17000 -11.5  11.3  325  35 18   7.9   4.3 | -11.1  12.0  330  42 21   7.4   4.1
 16500 -10.3  13.5  325  35 18   7.3   4.0 | -10.0  14.0  330  41 21   7.2   4.0
 16000  -9.3  15.3  325  34 18   7.1   3.9 |  -8.9  16.0  330  41 21   7.2   3.9
 15500  -8.2  17.2  325  33 17   7.2   3.9 |  -7.9  17.8  325  41 21   6.9   3.8
 15000  -7.2  19.0  325  33 17   7.3   4.0 |  -6.9  19.6  325  40 20   6.4   3.5
 14500  -6.1  21.0  325  32 17   7.3   4.0 |  -6.0  21.2  325  39 20   6.4   3.5
 14000  -5.0  23.0  325  32 16   7.2   3.9 |  -5.0  23.0  325  38 19   6.4   3.5
 13500  -3.9  25.0  325  32 16   7.2   4.0 |  -4.1  24.6  325  37 19   6.4   3.5
 13000  -2.9  26.8  325  31 16   7.1   3.9 |  -3.2  26.2  325  36 18   6.2   3.4
 12500  -1.8  28.8  325  30 16   7.2   4.0 |  -2.3  27.9  325  34 18   6.3   3.4
 12000  -0.8  30.6  325  29 15   6.2   3.4 |  -1.4  29.5  325  33 17   5.4   3.0
 11500   0.1  32.2  325  28 15   6.2   3.4 |  -0.6  30.9  320  31 16   5.4   3.0
 11000   1.1  34.0  325  27 14   6.8   3.7 |   0.3  32.5  320  29 15   6.2   3.4
 10500   2.1  35.8  325  25 13   7.4   4.1 |   1.2  34.2  315  27 14   6.6   3.6
 10250   2.6  36.7  325  25 13   3.1   1.7 |   1.6  34.9  315  26 13   2.4   1.3
 10000   2.7  36.9  325  24 13   4.1   2.2 |   1.7  35.1  315  26 13   3.7   2.0
  9750   3.3  37.9  325  24 12   8.9   4.9 |   2.3  36.1  310  26 13   8.5   4.7
  9500   3.9  39.0  320  23 12   7.6   4.1 |   2.8  37.0  310  25 13   7.1   3.9
  9250   4.5  40.1  320  22 11   5.7   3.1 |   3.3  37.9  305  25 13   5.5   3.0
  9000   4.8  40.6  320  23 12   4.6   2.5 |   3.7  38.7  300  25 13   4.9   2.7
  8750   5.2  41.4  315  23 12   6.1   3.3 |   4.1  39.4  300  25 13   6.2   3.4
  8500   5.7  42.3  310  24 12   5.7   3.2 |   4.6  40.3  295  25 13   6.5   3.6
  8250   6.1  43.0  310  24 12   4.7   2.6 |   5.1  41.2  295  23 12   6.8   3.8
  8000   6.4  43.5  305  23 12   4.6   2.5 |   5.6  42.1  290  22 11   6.9   3.8
  7750   6.8  44.2  305  23 12   4.6   2.5 |   6.1  43.0  290  20 10   7.6   4.2
  7500   7.1  44.8  300  21 11   6.2   3.4 |   6.7  44.1  290  18  9   7.1   3.9
  7250   7.6  45.7  305  19 10   7.4   4.1 |   7.1  44.8  290  15  8   6.1   3.4
  7000   8.2  46.8  305  17  9   7.4   4.1 |   7.6  45.7  290  13  7   6.7   3.7
  6750   8.7  47.7  305  15  8   6.1   3.4 |   8.1  46.6  295  11  6   5.8   3.2
  6500   9.0  48.2  310  13  7   2.7   1.5 |   8.4  47.1  295   8  4   3.0   1.7
  6250   9.1  48.4  315  11  5   2.5   1.4 |   8.6  47.5  290   5  3   2.0   1.1
  6000   9.3  48.7  325   8  4   0.1   0.0 |   8.7  47.7  275   2  1   2.2   1.2
  5750   8.8  47.8  325   5  3 -13.3  -7.3 |   8.6  47.5  210   2  1  -6.6  -3.6
  5500   7.0  44.6  280   1  1 -26.7 -14.6 |   7.3  45.1  190   3  1 -19.8 -10.9
________________________________________________________________________________

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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