Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 071333
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0633 MST Wednesday, December 7, 2016

This forecast is for Wednesday, December 7, 2016:

If the trigger temperature of 22.1 F/-5.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5285 ft MSL (0 ft AGL)

Forecast maximum temperature................... 14.0 F/-10.5 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Thursday 12/08..... Poor

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)................ Weak NVA
Potential height of wave....................... 33050 ft MSL (27765 ft AGL)
Wave soaring outlook for Thursday 12/08........ Poor

Remarks...

Sunrise/Sunset.................... 07:07:49 / 16:34:44 MST
Total possible sunshine........... 9 hr 26 min 55 sec (566 min 55 sec)
Altitude of sun at 11:51:16 MST... 27.49 degrees

Upper air data from rawinsonde observation taken on 12/07/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 11643 ft MSL (6358 ft AGL)
Lifted condensation level....... 7695 ft MSL (2410 ft AGL)
Lifted index.................... +17.7
K index......................... -3.2

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  -57.0 -70.6   270   73   38  -3.3  -1.8  109.8 229.7    67.6      M    M
 45000  -55.2 -67.4   265   78   40   2.8   1.5   87.4 189.2    58.9      M    M
 40000  -50.7 -59.3   270   86   44   2.9   1.6   69.6 157.4    51.7      M    M
 38000  -48.9 -56.0   270   89   46   3.3   1.8   64.1 147.4    49.3      M    M
 36000  -47.2 -53.0   275   89   46   0.8   0.5   58.1 136.5    46.4      M    M
 34000  -46.7 -52.1   275   94   48   0.8   0.4   50.3 122.5    42.2      M    M
 32000  -46.6 -51.9   270   98   50  -0.3  -0.2   42.1 107.8    37.4      M    M
 30000  -46.8 -52.2   265   98   50  -0.3  -0.2   34.0  93.2    32.4      M    M
 29000  -46.9 -52.4   270   97   50  -0.2  -0.1   29.9  85.9    29.8      M    M
 28000  -46.3 -51.3   270   98   50   4.4   2.4   25.8  78.4    27.2      M    M
 27000  -45.0 -49.0   265   98   51   4.4   2.4   23.7  74.6    25.9      M    M
 26000  -43.7 -46.7   265   99   51   4.4   2.4   21.7  71.1    24.7      M    M
 25000  -42.4 -44.3   270   96   50   4.4   2.4   19.7  67.4    23.4      M    M
 24000  -41.3 -42.3   270   87   45   0.5   0.3   17.3  63.2    21.8      M    M
 23000  -41.1 -42.0   270   77   40   0.4   0.2   13.9  57.0    19.3      M    M
 22000  -40.3 -40.5   260   75   38   1.7   0.9   11.3  52.3    17.4      M    M
 21000  -40.3 -40.5   260   73   38   1.8   1.0    7.7  45.9    14.7      M    M
 20000  -38.2 -36.8   255   72   37   8.0   4.4    6.8  44.2    14.1      M    M
 19500  -37.0 -34.6   255   69   36   7.9   4.4    6.4  43.5    13.8      M    M
 19000  -35.8 -32.4   255   66   34   7.9   4.4    6.0  42.9    13.6      M    M
 18500  -34.6 -30.3   260   63   32   7.9   4.4    5.7  42.3    13.4      M    M
 18000  -33.5 -28.3   260   60   31   8.0   4.4    5.4  41.8    13.2      M    M
 17500  -32.3 -26.1   260   57   29   7.4   4.1    5.1  41.2    13.0      M    M
 17000  -31.2 -24.2   265   52   27   7.4   4.1    4.7  40.4    12.7      M    M
 16500  -30.1 -22.2   265   49   25   7.4   4.1    4.3  39.7    12.5      M    M
 16000  -29.0 -20.2   270   45   23   7.4   4.1    3.9  39.1    12.2      M    M
 15500  -27.9 -18.2   270   41   21   7.4   4.1    3.5  38.3    11.9      M    M
 15000  -26.8 -16.2   275   38   19   7.4   4.1    3.1  37.6    11.6      M    M
 14500  -25.7 -14.3   275   34   18   7.4   4.1    2.7  36.9    11.3      M    M
 14000  -24.0 -11.2   280   30   15   7.4   4.1    2.1  35.9    10.9      M    M
 13500  -22.9  -9.2   285   28   15   7.4   4.1    1.7  35.1    10.6      M    M
 13000  -21.8  -7.2   290   27   14   7.4   4.1    1.3  34.4    10.3      M    M
 12500  -20.7  -5.3   290   26   13   7.4   4.1    1.0  33.7    10.0      M    M
 12000  -19.7  -3.5   295   24   13   7.5   4.1    0.6  33.1     9.7      M    M
 11500  -18.6  -1.5   295   21   11   8.2   4.5    0.2  32.4     9.4      M    M
 11000  -17.9  -0.2   300   17    9  -0.1  -0.0   -0.6  30.9     8.6      M    M
 10500  -17.9  -0.2   300   14    7  -0.1  -0.0   -2.2  28.0     7.2      M    M
 10250  -17.9  -0.2   305   12    6   0.1   0.0   -3.0  26.7     6.5      M    M
 10000  -17.9  -0.2   310   11    6  -0.4  -0.2   -3.7  25.3     5.8      M    M
  9750  -17.9  -0.2   325   10    5   1.4   0.8   -4.5  23.9     5.1      M    M
  9500  -17.7   0.1   330   10    5   3.5   1.9   -5.0  22.9     4.6      M    M
  9250  -17.4   0.7   335   10    5   5.8   3.2   -5.5  22.2     4.2      M    M
  9000  -16.8   1.8   340   10    5   7.7   4.2   -5.7  21.8     4.0      M    M
  8750  -16.3   2.7   340    8    4   7.2   3.9   -5.9  21.5     3.8      M    M
  8500  -15.8   3.6   335    7    4   7.3   4.0   -6.0  21.1     3.6      M    M
  8250  -15.2   4.6   330    5    3   7.3   4.0   -6.2  20.8     3.5      M    M
  8000  -14.7   5.5   325    4    2   7.2   4.0   -6.4  20.5     3.3      M    M
  7750  -14.1   6.6   325    2    1   7.5   4.1   -6.6  20.1     3.1      M    M
  7500  -13.6   7.5   145    1    0   6.5   3.6   -6.8  19.8     2.9      M    M
  7250  -13.2   8.2   145    3    1   5.3   2.9   -7.1  19.2     2.6      M    M
  7000  -12.8   9.0   145    5    3   5.1   2.8   -7.4  18.6     2.3      M    M
  6750  -12.4   9.7   135    5    3   6.5   3.6   -7.8  18.0     1.9      M    M
  6500  -11.8  10.8   125    6    3   8.8   4.8   -7.9  17.7     1.8      M    M
  6250  -11.2  11.8   115    6    3   9.0   4.9   -8.0  17.6     1.7      M    M
  6000  -10.5  13.1   110    7    4   9.0   4.9   -8.0  17.5     1.7      M    M
  5750   -9.8  14.4   100    7    3   8.8   4.8   -8.1  17.4     1.6      M    M
  5500   -9.2  15.4   085    7    3   9.5   5.2   -8.2  17.3     1.6      M    M

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

           12/07/2016 at 0800 MST          |       12/07/2016 at 1100 MST
                                           |
CAPE...    +6.7    LI...       +3.3        | CAPE...    +3.7    LI...       +4.1
CINH...    -0.5    K Index...  -1.7        | CINH...    -0.1    K Index...  -5.1
                                           |
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 -57.4 -71.3  270  37 19   2.0   1.1 | -57.6 -71.7  275  37 19   2.0   1.1
 45000 -54.2 -65.6  270  39 20   2.0   1.1 | -54.5 -66.1  275  40 20   2.0   1.1
 40000 -50.8 -59.4  275  43 22   2.3   1.3 | -51.2 -60.2  280  43 22   2.3   1.2
 38000 -49.4 -56.9  275  45 23   2.0   1.1 | -49.8 -57.6  280  45 23   1.9   1.1
 36000 -48.6 -55.5  275  47 24   1.4   0.8 | -48.9 -56.0  280  46 24   1.6   0.9
 34000 -47.8 -54.0  275  48 25   1.4   0.8 | -47.9 -54.2  280  47 24   1.6   0.9
 32000 -46.8 -52.2  275  49 25   1.8   1.0 | -46.6 -51.9  280  47 24   2.3   1.3
 30000 -45.6 -50.1  270  49 25   1.8   1.0 | -45.2 -49.4  280  47 24   2.3   1.3
 29000 -44.9 -48.8  270  49 25   3.0   1.7 | -44.4 -47.9  280  46 24   3.1   1.7
 28000 -44.1 -47.4  270  49 25   2.9   1.6 | -43.5 -46.3  280  46 24   3.1   1.7
 27000 -43.2 -45.8  275  48 25   2.9   1.6 | -42.6 -44.7  285  46 24   3.1   1.7
 26000 -42.3 -44.1  275  47 24   2.9   1.6 | -41.7 -43.1  285  45 23   3.1   1.7
 25000 -41.5 -42.7  275  45 23   2.6   1.4 | -40.8 -41.4  285  44 23   2.9   1.6
 24000 -40.7 -41.3  275  43 22   2.6   1.4 | -39.9 -39.8  285  43 22   2.9   1.6
 23000 -40.0 -40.0  275  40 21   2.6   1.4 | -39.1 -38.4  290  41 21   2.9   1.6
 22000 -39.2 -38.6  275  36 19   2.4   1.3 | -38.3 -36.9  290  39 20   2.5   1.4
 21000 -38.5 -37.3  275  33 17   2.4   1.3 | -37.6 -35.7  295  36 19   2.5   1.4
 20000 -37.8 -36.0  275  29 15   3.3   1.8 | -36.8 -34.2  295  34 17   2.8   1.5
 19500 -37.2 -35.0  275  27 14   3.8   2.1 | -36.4 -33.5  300  32 17   2.9   1.6
 19000 -36.7 -34.1  275  25 13   3.8   2.1 | -36.0 -32.8  300  31 16   2.9   1.6
 18500 -36.1 -33.0  275  23 12   3.8   2.1 | -35.5 -31.9  300  30 15   2.9   1.6
 18000 -35.5 -31.9  275  22 11   3.6   2.0 | -35.1 -31.2  305  29 15   2.7   1.5
 17500 -34.8 -30.6  275  20 10   7.0   3.8 | -34.2 -29.6  310  27 14   5.6   3.1
 17000 -33.1 -27.6  275  18  9   7.5   4.1 | -33.3 -27.9  310  27 14   5.4   2.9
 16500 -32.0 -25.6  280  17  9   8.0   4.4 | -32.4 -26.3  315  26 14   7.5   4.1
 16000 -30.8 -23.4  280  16  8   8.0   4.4 | -31.3 -24.3  315  26 14   7.3   4.0
 15500 -29.6 -21.3  280  15  7   8.1   4.5 | -30.1 -22.2  320  26 14   8.1   4.4
 15000 -28.4 -19.1  280  14  7   8.1   4.5 | -28.9 -20.0  320  27 14   8.2   4.5
 14500 -27.1 -16.8  285  13  7   8.0   4.4 | -27.7 -17.9  325  27 14   7.9   4.3
 14000 -26.0 -14.8  285  12  6   8.0   4.4 | -26.6 -15.9  330  28 14   7.8   4.3
 13500 -24.8 -12.6  290  11  6   7.8   4.3 | -25.4 -13.7  330  29 15   7.7   4.2
 13000 -23.6 -10.5  290  11  6   7.6   4.2 | -24.3 -11.7  335  30 15   7.6   4.2
 12500 -22.5  -8.5  295  10  5   7.2   3.9 | -23.1  -9.6  335  31 16   7.5   4.1
 12000 -21.5  -6.7  295   9  5   7.0   3.9 | -22.0  -7.6  340  32 16   7.5   4.1
 11500 -20.5  -4.9  295   9  4   5.1   2.8 | -21.0  -5.8  340  32 17   6.3   3.5
 11000 -19.9  -3.8  295   7  4   4.6   2.5 | -20.1  -4.2  340  32 16   6.4   3.5
 10500 -19.3  -2.7  295   6  3   2.6   1.4 | -19.3  -2.7  345  30 15   3.2   1.8
 10250 -19.2  -2.6  295   5  3   2.4   1.3 | -19.1  -2.4  345  28 14   3.2   1.8
 10000 -19.0  -2.2  295   4  2   2.1   1.2 | -18.9  -2.0  345  26 13   3.4   1.8
  9750 -18.8  -1.8  295   3  2   3.6   2.0 | -18.7  -1.7  345  23 12   2.0   1.1
  9500 -18.5  -1.3  295   2  1   5.0   2.8 | -18.6  -1.5  340  19 10   0.5   0.3
  9250 -18.1  -0.6  305   2  1   4.7   2.6 | -18.6  -1.5  340  14  7   0.3   0.1
  9000 -17.8  -0.0  325   1  1   4.6   2.5 | -18.5  -1.3  340  10  5   1.0   0.6
  8750 -17.5   0.5  010   1  1   4.2   2.3 | -18.4  -1.1  320   5  3   2.7   1.5
  8500 -17.1   1.2  035   2  1   4.4   2.4 | -18.1  -0.6  320   3  2   4.1   2.3
  8250 -16.8   1.8  040   3  1   4.6   2.5 | -17.8  -0.0  350   8  4   4.4   2.4
  8000 -16.5   2.3  040   3  2   4.2   2.3 | -17.5   0.5  360  11  6   3.2   1.7
  7750 -16.2   2.8  040   5  2   4.1   2.2 | -17.3   0.9  005  11  6   2.5   1.4
  7500 -15.9   3.4  035   5  3   4.3   2.4 | -17.2   1.0  005  12  6   1.6   0.9
  7250 -15.5   4.1  035   6  3   5.2   2.9 | -17.0   1.4  010  12  6   3.5   1.9
  7000 -15.1   4.8  030   6  3   6.3   3.5 | -16.7   1.9  010  12  6   5.4   2.9
  6750 -14.6   5.7  025   7  3   5.8   3.2 | -16.3   2.7  010  12  6   5.6   3.1
  6500 -14.2   6.4  020   7  4   6.2   3.4 | -15.8   3.6  010  13  6   8.2   4.5
  6250 -13.7   7.3  020   7  3   7.8   4.3 | -15.1   4.8  010  12  6   9.4   5.2
  6000 -13.1   8.4  015   6  3   8.1   4.5 | -14.4   6.1  010  12  6   8.6   4.7
  5750 -12.5   9.5  015   6  3   8.2   4.5 | -13.7   7.3  010  12  6  11.1   6.1
  5500 -11.8  10.8  015   5  3   9.6   5.3 | -12.7   9.1  010  12  6  17.9   9.8

           12/07/2016 at 1400 MST          |       12/07/2016 at 1700 MST
                                           |
CAPE...    +5.6    LI...       +4.4        | CAPE...     0.0    LI...       +5.9
CINH...     0.0    K Index...  -4.2        | CINH...    -0.2    K Index...  -6.7
                                           |
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 -57.9 -72.2  280  38 20   1.9   1.0 | -58.2 -72.8  295  41 21   1.9   1.0
 45000 -54.9 -66.8  280  42 22   1.9   1.0 | -55.2 -67.4  295  45 23   1.9   1.0
 40000 -51.8 -61.2  285  45 23   2.2   1.2 | -52.5 -62.5  290  49 25   1.8   1.0
 38000 -50.5 -58.9  285  46 24   1.9   1.1 | -51.4 -60.5  290  50 26   1.9   1.0
 36000 -49.4 -56.9  285  47 24   1.8   1.0 | -50.3 -58.5  295  51 26   1.9   1.0
 34000 -48.4 -55.1  285  47 24   1.8   1.0 | -49.1 -56.4  295  51 26   1.9   1.0
 32000 -46.9 -52.4  290  48 25   2.5   1.4 | -47.4 -53.3  300  53 27   3.0   1.6
 30000 -45.4 -49.7  290  48 25   2.5   1.4 | -45.6 -50.1  300  54 28   3.0   1.6
 29000 -44.5 -48.1  295  48 25   3.3   1.8 | -44.6 -48.3  305  55 28   3.6   2.0
 28000 -43.6 -46.5  295  48 25   3.2   1.8 | -43.5 -46.3  305  54 28   3.6   2.0
 27000 -42.6 -44.7  295  47 24   3.2   1.8 | -42.5 -44.5  305  54 28   3.6   2.0
 26000 -41.6 -42.9  295  47 24   3.3   1.8 | -41.4 -42.5  305  53 27   3.8   2.1
 25000 -40.6 -41.1  295  46 24   3.6   2.0 | -40.2 -40.4  305  52 27   4.1   2.3
 24000 -39.5 -39.1  295  45 23   3.6   1.9 | -38.9 -38.0  305  50 26   4.1   2.3
 23000 -38.5 -37.3  295  44 23   3.5   1.9 | -37.7 -35.9  305  49 25   3.9   2.1
 22000 -37.6 -35.7  300  42 21   2.6   1.4 | -36.7 -34.1  305  46 24   3.4   1.8
 21000 -36.8 -34.2  300  39 20   2.6   1.4 | -35.7 -32.3  305  44 23   3.4   1.9
 20000 -36.0 -32.8  300  37 19   2.6   1.4 | -34.7 -30.5  310  42 21   2.4   1.3
 19500 -35.7 -32.3  305  35 18   2.6   1.4 | -34.3 -29.7  310  40 21   2.4   1.3
 19000 -35.3 -31.5  305  34 17   2.6   1.4 | -34.0 -29.2  310  38 20   2.4   1.3
 18500 -34.9 -30.8  305  32 17   2.6   1.4 | -33.6 -28.5  315  37 19   2.4   1.3
 18000 -34.3 -29.7  305  30 15   3.2   1.8 | -33.1 -27.6  315  34 18   2.9   1.6
 17500 -33.7 -28.7  305  29 15   4.3   2.4 | -32.6 -26.7  315  33 17   3.3   1.8
 17000 -33.0 -27.4  305  27 14   4.3   2.3 | -32.1 -25.8  320  31 16   3.5   1.9
 16500 -32.2 -26.0  305  26 13   6.5   3.6 | -31.4 -24.5  320  30 16   5.2   2.8
 16000 -31.3 -24.3  305  25 13   6.2   3.4 | -30.7 -23.3  320  29 15   4.9   2.7
 15500 -30.2 -22.4  305  24 13   7.9   4.3 | -29.8 -21.6  320  29 15   7.0   3.9
 15000 -29.1 -20.4  305  24 12   7.9   4.3 | -28.8 -19.8  325  28 15   6.7   3.7
 14500 -27.9 -18.2  310  23 12   8.1   4.5 | -27.7 -17.9  325  28 15   7.6   4.2
 14000 -26.7 -16.1  310  23 12   8.2   4.5 | -26.6 -15.9  325  29 15   7.6   4.2
 13500 -25.5 -13.9  310  23 12   7.9   4.3 | -25.4 -13.7  330  29 15   7.7   4.2
 13000 -24.3 -11.7  315  23 12   7.9   4.3 | -24.3 -11.7  330  30 16   7.8   4.3
 12500 -23.1  -9.6  320  23 12   7.7   4.2 | -23.1  -9.6  335  32 16   7.5   4.1
 12000 -22.0  -7.6  325  24 12   7.7   4.2 | -22.0  -7.6  340  35 18   7.5   4.1
 11500 -20.9  -5.6  330  26 13   7.2   4.0 | -20.9  -5.6  345  39 20   7.1   3.9
 11000 -19.8  -3.6  340  28 15   7.4   4.1 | -19.9  -3.8  345  44 23   7.2   4.0
 10500 -18.9  -2.0  345  33 17   5.4   3.0 | -18.9  -2.0  350  51 26   5.4   3.0
 10250 -18.4  -1.1  345  36 19   5.5   3.0 | -18.5  -1.3  350  55 29   5.7   3.1
 10000 -18.0  -0.4  350  39 20   5.8   3.2 | -18.1  -0.6  355  60 31   5.5   3.0
  9750 -17.6   0.3  350  44 23   4.3   2.4 | -17.7   0.1  355  67 34   4.2   2.3
  9500 -17.4   0.7  355  50 26   1.6   0.9 | -17.5   0.5  355  74 38   2.2   1.2
  9250 -17.3   0.9  355  56 29   1.3   0.7 | -17.4   0.7  355  78 40   1.9   1.0
  9000 -17.3   0.9  355  62 32   0.6   0.3 | -17.2   1.0  355  83 43   1.1   0.6
  8750 -17.3   0.9  355  72 37  -0.4  -0.2 | -17.2   1.0  355  90 46   0.1   0.0
  8500 -17.3   0.9  360  86 44   0.5   0.3 | -17.2   1.0  360  97 50   0.2   0.1
  8250 -17.2   1.0  360 104 54   0.6   0.3 | -17.2   1.0  360 105 54  -0.0  -0.0
  8000 -17.2   1.0  360  93 48  -0.5  -0.3 | -17.2   1.0  360 111 57  -0.0  -0.0
  7750 -17.3   0.9  360  38 20  -0.4  -0.2 | -17.2   1.0  360 117 60  -0.2  -0.1
  7500 -17.3   0.9  005   8  4   0.7   0.4 | -17.2   1.0  360  77 40   0.3   0.2
  7250 -17.1   1.2  010  10  5   4.3   2.4 | -17.1   1.2  015   4  2   2.9   1.6
  7000 -16.7   1.9  010  10  5   6.6   3.6 | -16.9   1.6  010   6  3   3.9   2.2
  6750 -16.2   2.8  010  11  6   6.4   3.5 | -16.6   2.1  010   8  4   4.9   2.7
  6500 -15.7   3.7  010  11  6   8.4   4.6 | -16.1   3.0  010   8  4   7.0   3.8
  6250 -15.0   5.0  010  11  6   9.4   5.2 | -15.6   3.9  010   8  4   7.1   3.9
  6000 -14.3   6.3  010  11  6   8.6   4.7 | -15.0   5.0  010   9  5   7.0   3.9
  5750 -13.6   7.5  010  11  6  11.1   6.1 | -14.5   5.9  010  10  5   6.9   3.8
  5500 -12.6   9.3  010  11  6  17.5   9.6 | -14.0   6.8  005  11  6   6.9   3.8
________________________________________________________________________________

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.

CINH (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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