Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 091226
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0525 MST Friday, December 9, 2016

This forecast is for Friday, December 9, 2016:

If the trigger temperature of 51.2 F/10.7 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 84 ft/min (0.4 m/s)
   Maximum height of thermals.................. 6668 ft MSL (1383 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... None
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................. 6474 ft MSL (1189 ft AGL)
Thermal soaring outlook for Saturday 12/10..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 16130 ft MSL (10845 ft AGL)
Wave soaring outlook for Saturday 12/10........ Good

Remarks...

Sunrise/Sunset.................... 07:09:31 / 16:34:49 MST
Total possible sunshine........... 9 hr 25 min 18 sec (565 min 18 sec)
Altitude of sun at 11:52:10 MST... 27.30 degrees

Upper air data from rawinsonde observation taken on 12/09/2016 at 0500 MST

Freezing level.................. 6476 ft MSL (1191 ft AGL)
Additional freezing level....... 8528 ft MSL (3243 ft AGL)
Convective condensation level... 15751 ft MSL (10466 ft AGL)
Lifted condensation level....... 11768 ft MSL (6483 ft AGL)
Lifted index.................... +9.6
K index......................... +9.1

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  -60.3 -76.5   295   66   34   5.3   2.9  101.6 214.9    53.9      M    M
 45000  -60.7 -77.3   290   78   40   4.5   2.5   76.1 169.0    42.3      M    M
 40000  -56.8 -70.2   280   68   35   2.0   1.1   58.8 137.9    34.0      M    M
 38000  -58.6 -73.5   280   64   33  -2.9  -1.6   47.5 117.5    27.3      M    M
 36000  -60.2 -76.4   295   68   35  -2.6  -1.4   36.3  97.3    20.4      M    M
 34000  -58.0 -72.4   300   74   38   6.8   3.7   31.0  87.9    17.2      M    M
 32000  -53.3 -63.9   295   76   39   6.1   3.3   28.5  83.3    15.9      M    M
 30000  -48.2 -54.8   295   77   40   8.5   4.7   27.5  81.5    15.6      M    M
 29000  -45.6 -50.1   295   76   39   8.6   4.7   27.0  80.6    15.4      M    M
 28000  -43.1 -45.6   295   75   39   8.6   4.7   26.6  79.8    15.3      M    M
 27000  -40.5 -40.9   295   74   38   8.6   4.7   26.3  79.4    15.2      M    M
 26000  -37.9 -36.2   295   72   37   8.7   4.8   25.8  78.4    15.0      M    M
 25000  -35.3 -31.5   295   70   36   7.9   4.3   25.3  77.5    14.8      M    M
 24000  -32.9 -27.2   290   67   34   8.1   4.4   24.6  76.3    14.4      M    M
 23000  -30.7 -23.3   290   64   33   7.1   3.9   23.6  74.5    13.8      M    M
 22000  -28.6 -19.5   290   61   31   7.1   3.9   22.6  72.7    13.1      M    M
 21000  -26.5 -15.7   285   58   30   7.1   3.9   21.8  71.2    12.5      M    M
 20000  -24.5 -12.1   285   55   28   6.6   3.6   20.8  69.4    11.8      M    M
 19500  -23.5 -10.3   285   52   27   6.6   3.6   20.2  68.3    11.4      M    M
 19000  -22.5  -8.5   290   50   26   6.6   3.6   19.6  67.3    11.0      M    M
 18500  -21.5  -6.7   290   47   24   6.9   3.8   19.1  66.3    10.6      M    M
 18000  -20.4  -4.7   295   45   23   8.3   4.5   18.8  65.8    10.4      M    M
 17500  -19.2  -2.6   295   46   24   8.2   4.5   18.5  65.3    10.2      M    M
 17000  -17.9  -0.2   295   47   24   8.2   4.5   18.2  64.8    10.0      M    M
 16500  -16.7   1.9   300   48   25   8.2   4.5   18.0  64.4     9.9      M    M
 16000  -14.9   5.2   300   49   25   8.2   4.5   17.7  63.8     9.6      M    M
 15500  -13.6   7.5   300   49   25   8.2   4.5   17.4  63.3     9.4      M    M
 15000  -12.4   9.7   300   48   25   8.2   4.5   17.1  62.8     9.2      M    M
 14500  -11.2  11.8   300   48   25   8.2   4.5   16.9  62.4     9.0      M    M
 14000  -10.0  14.0   300   48   25   8.2   4.5   16.7  62.0     8.9      M    M
 13500   -8.7  16.3   300   49   25   8.2   4.5   16.3  61.4     8.6      M    M
 13000   -7.5  18.5   295   50   26   8.2   4.5   16.0  60.9     8.4      M    M
 12500   -6.3  20.7   295   50   26   8.1   4.5   15.8  60.4     8.2      M    M
 12000   -5.1  22.8   295   51   26   5.1   2.8   15.5  59.9     8.0      M    M
 11500   -4.8  23.4   295   50   26   2.7   1.5   14.3  57.8     6.8      M    M
 11000   -4.4  24.1   295   49   25   2.6   1.4   13.2  55.7     5.8      M    M
 10500   -3.7  25.3   295   44   22   6.5   3.6   12.4  54.3     5.0      M    M
 10250   -3.3  26.1   295   41   21   6.0   3.3   12.1  53.7     4.7      M    M
 10000   -2.8  27.0   295   39   20   6.4   3.5   11.8  53.2     4.5      M    M
  9750   -2.3  27.9   295   36   18   6.6   3.6   11.5  52.8     4.2      M    M
  9500   -1.9  28.6   290   33   17   6.6   3.6   11.3  52.3     4.0      M    M
  9250   -1.4  29.5   290   30   15   6.6   3.6   11.1  51.9     3.8      M    M
  9000   -0.9  30.4   285   27   14   6.6   3.6   10.8  51.5     3.6      M    M
  8750   -0.4  31.3   285   25   13   6.6   3.6   10.6  51.0     3.3      M    M
  8500    0.1  32.2   285   22   12   6.6   3.6   10.3  50.6     3.1      M    M
  8250    0.6  33.1   280   20   10   6.6   3.6   10.1  50.1     2.8      M    M
  8000    1.0  33.8   280   18    9   6.6   3.6    9.8  49.7     2.6      M    M
  7750    1.5  34.7   280   17    9   6.5   3.6    9.6  49.3     2.4      M    M
  7500    2.0  35.6   275   15    8   7.0   3.8    9.3  48.8     2.1      M    M
  7250    2.5  36.5   275   14    7   5.1   2.8    9.1  48.4     1.9      M    M
  7000    3.0  37.4   270   13    7  12.1   6.7    8.9  47.9     1.6      M    M
  6750    3.5  38.3   265   12    6 -14.1  -7.7    8.6  47.5     1.4      M    M
  6500    0.7  33.3   260   12    6 -49.6 -27.2    5.0  40.9    -2.1    130  0.7
  6250   -3.4  25.9   255   11    6 -68.9 -37.8   -0.0  31.9    -7.0    246  1.3
  6000   -8.9  16.0   245   11    6 -67.0 -36.7   -6.4  20.4   -13.3    404  2.1
  5750  -12.3   9.9   240    8    4 -25.9 -14.2  -10.7  12.8   -17.4    499  2.5
  5500  -13.2   8.2   220    6    3  -3.9  -2.1  -12.3   9.9   -19.1    518  2.6

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

           12/09/2016 at 0800 MST          |       12/09/2016 at 1100 MST
                                           |
CAPE...     0.0    LI...       +4.3        | CAPE...     0.0    LI...       +5.4
CINH...     0.0    K Index...  +6.4        | CINH...    -0.4    K Index...  +3.3
                                           |
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 -60.2 -76.4  290  26 13   0.5   0.2 | -60.4 -76.7  280  18  9   0.5   0.3
 45000 -59.4 -74.9  285  38 20   0.5   0.3 | -59.6 -75.3  285  36 18   0.5   0.3
 40000 -63.5 -82.3  300  35 18  -3.0  -1.6 | -63.7 -82.7  300  34 18  -3.0  -1.7
 38000 -63.5 -82.3  300  34 18   5.8   3.2 | -63.7 -82.7  300  35 18   5.9   3.2
 36000 -60.0 -76.0  295  35 18   5.9   3.2 | -60.1 -76.2  300  37 19   5.9   3.3
 34000 -56.5 -69.7  290  35 18   7.2   4.0 | -56.5 -69.7  300  39 20   7.2   4.0
 32000 -51.0 -59.8  290  33 17   8.1   4.5 | -51.2 -60.2  300  37 19   7.8   4.3
 30000 -46.0 -50.8  290  31 16   8.8   4.8 | -46.5 -51.7  305  35 18   7.8   4.3
 29000 -43.4 -46.1  290  31 16   8.8   4.8 | -44.2 -47.6  305  33 17   7.9   4.3
 28000 -40.8 -41.4  290  30 15   8.7   4.8 | -41.8 -43.2  300  32 16   7.9   4.3
 27000 -38.2 -36.8  295  29 15   8.4   4.6 | -39.4 -38.9  300  30 15   8.1   4.5
 26000 -35.9 -32.6  295  29 15   7.2   4.0 | -36.9 -34.4  300  29 15   8.6   4.7
 25000 -33.8 -28.8  295  30 15   7.2   4.0 | -34.3 -29.7  300  27 14   8.6   4.7
 24000 -31.6 -24.9  300  30 15   7.2   4.0 | -31.7 -25.1  300  26 13   8.6   4.7
 23000 -29.5 -21.1  300  30 15   6.9   3.8 | -29.3 -20.7  300  25 13   7.8   4.3
 22000 -27.5 -17.5  300  29 15   6.9   3.8 | -26.9 -16.4  300  24 12   7.8   4.3
 21000 -25.4 -13.7  300  29 15   7.0   3.9 | -24.6 -12.3  305  23 12   7.5   4.1
 20000 -23.3  -9.9  300  25 13   7.2   3.9 | -22.4  -8.3  305  23 12   7.2   3.9
 19500 -22.2  -8.0  295  24 12   7.2   3.9 | -21.4  -6.5  305  23 12   7.2   3.9
 19000 -21.1  -6.0  295  22 12   7.2   3.9 | -20.3  -4.5  305  24 12   7.2   3.9
 18500 -20.1  -4.2  290  21 11   7.3   4.0 | -19.2  -2.6  305  24 12   7.1   3.9
 18000 -19.0  -2.2  290  20 10   7.6   4.2 | -18.2  -0.8  300  23 12   6.9   3.8
 17500 -17.8  -0.0  285  19 10   7.6   4.2 | -17.2   1.0  300  21 11   7.0   3.8
 17000 -16.7   1.9  285  18  9   7.1   3.9 | -16.1   3.0  300  21 11   6.8   3.8
 16500 -15.7   3.7  285  17  9   7.1   3.9 | -14.6   5.7  300  21 11   6.9   3.8
 16000 -14.6   5.7  285  17  9   6.8   3.7 | -13.6   7.5  295  21 11   6.8   3.7
 15500 -13.2   8.2  290  19 10   6.5   3.5 | -12.6   9.3  295  22 11   6.9   3.8
 15000 -12.2  10.0  295  20 10   6.4   3.5 | -11.6  11.1  295  22 12   6.1   3.3
 14500 -11.3  11.7  295  22 11   6.4   3.5 | -10.7  12.7  295  23 12   6.1   3.3
 14000 -10.4  13.3  295  24 12   6.0   3.3 |  -9.8  14.4  290  23 12   6.3   3.5
 13500  -9.5  14.9  300  24 12   5.8   3.2 |  -8.9  16.0  295  23 12   6.4   3.5
 13000  -8.7  16.3  300  24 12   6.4   3.5 |  -8.0  17.6  295  22 12   5.8   3.2
 12500  -7.6  18.3  305  24 12   6.9   3.8 |  -7.2  19.0  295  23 12   5.4   3.0
 12000  -6.6  20.1  305  24 12   7.1   3.9 |  -6.4  20.5  295  24 13   5.2   2.9
 11500  -5.6  21.9  305  24 12   7.2   3.9 |  -5.7  21.7  295  23 12   5.1   2.8
 11000  -4.5  23.9  305  24 12   6.6   3.6 |  -4.9  23.2  295  22 12   4.8   2.7
 10500  -3.6  25.5  305  22 12   6.1   3.4 |  -4.3  24.3  295  22 11   4.9   2.7
 10250  -3.2  26.2  305  22 11   5.5   3.0 |  -3.9  25.0  295  21 11   3.7   2.0
 10000  -2.9  26.8  305  21 11   2.9   1.6 |  -3.7  25.3  295  21 11   3.5   1.9
  9750  -2.7  27.1  305  21 11   3.8   2.1 |  -3.4  25.9  295  20 10   5.8   3.2
  9500  -2.3  27.9  305  20 10   5.9   3.2 |  -2.9  26.8  295  19 10   6.8   3.7
  9250  -1.9  28.6  300  19 10   5.0   2.8 |  -2.4  27.7  295  18  9   5.6   3.1
  9000  -1.6  29.1  300  19 10   4.2   2.3 |  -2.1  28.2  295  17  9   4.3   2.4
  8750  -1.3  29.7  295  18  9   3.7   2.0 |  -1.7  28.9  295  16  8   6.1   3.3
  8500  -1.0  30.2  295  16  8   4.1   2.3 |  -1.2  29.8  295  15  8   7.5   4.1
  8250  -0.7  30.7  290  15  8   3.0   1.6 |  -0.7  30.7  295  14  7   6.7   3.7
  8000  -0.6  30.9  290  14  7   1.8   1.0 |  -0.2  31.6  295  12  6   6.5   3.6
  7750  -0.4  31.3  285  12  6   1.5   0.8 |   0.3  32.5  295  11  6   6.3   3.5
  7500  -0.3  31.5  285  10  5   0.9   0.5 |   0.8  33.4  290   9  5   6.0   3.3
  7250  -0.3  31.5  275   8  4   0.9   0.5 |   1.2  34.2  285   8  4   5.8   3.2
  7000  -0.2  31.6  265   7  3   0.0   0.0 |   1.6  34.9  280   6  3   5.7   3.1
  6750  -0.2  31.6  250   5  3   2.4   1.3 |   2.1  35.8  270   5  3   5.8   3.2
  6500   0.0  32.0  225   5  2  -0.7  -0.4 |   2.5  36.5  250   4  2   3.3   1.8
  6250  -0.3  31.5  215   4  2  -6.4  -3.5 |   2.6  36.7  240   4  2   0.6   0.3
  6000  -0.7  30.7  205   4  2  -1.9  -1.0 |   2.7  36.9  225   4  2   3.5   1.9
  5750  -1.0  30.2  195   4  2 -14.2  -7.8 |   2.8  37.0  210   4  2  -5.3  -2.9
  5500  -3.6  25.5  185   4  2 -61.3 -33.7 |   1.3  34.3  200   3  1 -36.8 -20.2

           12/09/2016 at 1400 MST          |       12/09/2016 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.9        | CAPE...     0.0    LI...       +5.9
CINH...     0.0    K Index...  +6.8        | CINH...    -0.3    K Index...  +9.4
                                           |
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 -60.2 -76.4  285  19 10  -0.7  -0.4 | -61.3 -78.3  290  22 11  -0.8  -0.4
 45000 -61.3 -78.3  280  40 20  -0.7  -0.4 | -62.6 -80.7  285  41 21  -0.8  -0.4
 40000 -65.8 -86.4  295  37 19  -3.2  -1.8 | -65.0 -85.0  290  37 19  -1.7  -0.9
 38000 -65.4 -85.7  295  36 19   7.3   4.0 | -64.3 -83.7  295  36 18   6.0   3.3
 36000 -61.1 -78.0  290  37 19   7.3   4.0 | -60.7 -77.3  290  36 19   6.0   3.3
 34000 -56.6 -69.9  285  38 19   8.4   4.6 | -57.0 -70.6  290  36 19   8.1   4.5
 32000 -50.8 -59.4  295  37 19   8.6   4.7 | -51.4 -60.5  290  34 18   8.4   4.6
 30000 -45.6 -50.1  300  36 18   8.6   4.7 | -46.2 -51.2  290  31 16   9.2   5.0
 29000 -43.1 -45.6  300  35 18   8.6   4.7 | -43.5 -46.3  285  29 15   9.2   5.1
 28000 -40.5 -40.9  300  35 18   8.6   4.7 | -40.7 -41.3  285  27 14   9.2   5.1
 27000 -37.9 -36.2  300  34 17   8.5   4.7 | -38.0 -36.4  285  25 13   8.8   4.9
 26000 -35.4 -31.7  300  32 16   8.4   4.6 | -35.4 -31.7  290  26 14   8.5   4.7
 25000 -32.9 -27.2  300  30 15   8.4   4.6 | -32.9 -27.2  295  28 15   8.5   4.7
 24000 -30.4 -22.7  295  28 14   8.3   4.6 | -30.4 -22.7  295  30 15   8.3   4.6
 23000 -28.1 -18.6  300  26 13   7.5   4.1 | -28.0 -18.4  295  30 15   7.8   4.3
 22000 -25.8 -14.4  300  24 13   7.5   4.1 | -25.7 -14.3  295  29 15   7.8   4.3
 21000 -23.6 -10.5  300  23 12   6.7   3.7 | -23.4 -10.1  295  28 14   7.0   3.9
 20000 -21.7  -7.1  300  22 11   6.2   3.4 | -21.5  -6.7  295  27 14   6.6   3.6
 19500 -20.8  -5.4  305  22 11   6.2   3.4 | -20.5  -4.9  295  26 14   6.6   3.6
 19000 -19.9  -3.8  305  22 11   6.2   3.4 | -19.5  -3.1  295  26 13   6.6   3.6
 18500 -19.0  -2.2  305  22 11   6.3   3.5 | -18.5  -1.3  295  25 13   6.6   3.6
 18000 -18.0  -0.4  305  22 11   6.5   3.6 | -17.0   1.4  295  24 13   6.6   3.6
 17500 -16.6   2.1  305  22 11   6.8   3.7 | -16.1   3.0  295  24 12   6.4   3.5
 17000 -15.5   4.1  305  22 11   7.2   4.0 | -15.1   4.8  290  23 12   6.2   3.4
 16500 -14.5   5.9  300  22 11   7.2   4.0 | -14.2   6.4  290  23 12   6.2   3.4
 16000 -13.4   7.9  300  22 11   7.2   3.9 | -13.3   8.1  290  23 12   6.4   3.5
 15500 -12.3   9.9  300  23 12   7.3   4.0 | -12.4   9.7  290  22 11   6.5   3.5
 15000 -11.4  11.5  295  23 12   5.5   3.0 | -11.5  11.3  290  22 11   5.7   3.2
 14500 -10.6  12.9  295  24 12   5.5   3.0 | -10.6  12.9  290  21 11   5.7   3.1
 14000  -9.8  14.4  290  25 13   5.4   3.0 |  -9.8  14.4  290  21 11   5.2   2.9
 13500  -9.0  15.8  290  24 12   5.4   2.9 |  -9.0  15.8  290  21 11   5.0   2.8
 13000  -8.2  17.2  285  23 12   5.1   2.8 |  -8.3  17.1  290  20 10   4.8   2.6
 12500  -7.5  18.5  285  22 12   4.9   2.7 |  -7.6  18.3  290  19 10   4.7   2.6
 12000  -6.8  19.8  285  22 11   5.4   3.0 |  -6.9  19.6  285  19 10   4.3   2.4
 11500  -6.0  21.2  285  20 10   5.8   3.2 |  -6.4  20.5  285  17  9   4.1   2.3
 11000  -5.1  22.8  285  19 10   5.6   3.1 |  -5.8  21.6  280  15  8   5.4   2.9
 10500  -4.3  24.3  285  17  9   5.8   3.2 |  -4.8  23.4  275  13  7   6.7   3.7
 10250  -3.9  25.0  285  16  8   4.1   2.2 |  -4.4  24.1  275  12  6   4.5   2.5
 10000  -3.7  25.3  285  15  8   4.2   2.3 |  -4.1  24.6  275  11  6   4.5   2.5
  9750  -3.3  26.1  285  14  7   7.2   4.0 |  -3.6  25.5  270  10  5   7.8   4.3
  9500  -2.7  27.1  285  13  7   7.9   4.3 |  -3.0  26.6  265   9  4   8.1   4.4
  9250  -2.1  28.2  280  11  6   7.2   4.0 |  -2.5  27.5  260   7  4   8.0   4.4
  9000  -1.6  29.1  280  10  5   6.2   3.4 |  -1.9  28.6  250   6  3   8.2   4.5
  8750  -1.2  29.8  280   9  5   6.4   3.5 |  -1.2  29.8  240   6  3   8.6   4.7
  8500  -0.7  30.7  280   8  4   6.9   3.8 |  -0.6  30.9  235   5  3   8.4   4.6
  8250  -0.2  31.6  280   7  4   6.4   3.5 |   0.1  32.2  225   5  3   9.8   5.4
  8000   0.3  32.5  280   6  3   6.0   3.3 |   0.9  33.6  215   5  2  11.4   6.3
  7750   0.7  33.3  275   5  2   6.1   3.3 |   1.7  35.1  205   5  2   9.6   5.3
  7500   1.2  34.2  270   4  2   6.4   3.5 |   2.3  36.1  195   4  2   8.9   4.9
  7250   1.7  35.1  260   3  2   7.5   4.1 |   3.1  37.6  190   4  2   9.8   5.3
  7000   2.3  36.1  240   2  1   7.9   4.3 |   3.8  38.8  185   4  2  10.2   5.6
  6750   2.9  37.2  215   2  1   8.1   4.4 |   4.6  40.3  175   4  2   9.2   5.1
  6500   3.5  38.3  190   2  1   6.6   3.6 |   5.0  41.0  170   3  2   0.4   0.2
  6250   3.9  39.0  180   2  1   4.5   2.5 |   4.7  40.5  165   3  1  -5.6  -3.1
  6000   4.3  39.7  170   2  1   6.9   3.8 |   4.4  39.9  150   2  1  -2.4  -1.3
  5750   4.7  40.5  165   2  1  -0.6  -0.3 |   4.0  39.2  130   2  1  -9.3  -5.1
  5500   3.6  38.5  160   2  1 -27.0 -14.8 |   2.4  36.3  130   2  1 -37.6 -20.6
________________________________________________________________________________

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.

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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