Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 101358
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0658 MST Saturday, December 10, 2016

This forecast is for Saturday, December 10, 2016:

If the trigger temperature of 57.3 F/14.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 155 ft/min (0.8 m/s)
   Maximum height of thermals.................. 9039 ft MSL (3754 ft AGL)

Forecast maximum temperature................... 57.0 F/14.3 C
Time of trigger temperature.................... 1200 MST
Time of overdevelopment........................ 1400 MST
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6457 ft MSL (1172 ft AGL)
Thermal soaring outlook for Sunday 12/11....... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... Improving
Height of stable layer (12-18K ft MSL)......... 18111 ft MSL (12826 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 18604 ft MSL (13319 ft AGL)
Wave soaring outlook for Sunday 12/11.......... Excellent

Remarks... Strong westerly flow aloft developing through today.

Sunrise/Sunset.................... 07:10:19 / 16:34:55 MST
Total possible sunshine........... 9 hr 24 min 36 sec (564 min 36 sec)
Altitude of sun at 11:52:37 MST... 27.22 degrees

Upper air data from rawinsonde observation taken on 12/10/2016 at 0500 MST

Freezing level.................. 5993 ft MSL (708 ft AGL)
Additional freezing level....... 10175 ft MSL (4890 ft AGL)
Convective condensation level... 17167 ft MSL (11882 ft AGL)
Lifted condensation level....... 13984 ft MSL (8698 ft AGL)
Lifted index.................... +8.2
K index......................... -15.0

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  -63.1 -81.6   285   64   33  -0.2  -0.1   96.1 205.0    46.8      M    M
 45000  -63.5 -82.3   275   83   43  -0.5  -0.3   70.7 159.3    34.7      M    M
 40000  -66.8 -88.2   280   64   33  -1.4  -0.7   42.2 107.9    18.5      M    M
 38000  -66.2 -87.2   290   57   30   6.2   3.4   34.4  93.9    13.8      M    M
 36000  -61.6 -78.9   305   62   32   9.4   5.2   32.6  90.6    12.9      M    M
 34000  -55.2 -67.4   300   64   33   9.2   5.0   32.1  89.7    13.0      M    M
 32000  -49.7 -57.5   295   66   34   9.2   5.0   31.4  88.6    12.9      M    M
 30000  -44.2 -47.6   295   67   34   9.3   5.1   31.3  88.3    13.1      M    M
 29000  -41.4 -42.5   295   64   33   9.3   5.1   30.8  87.5    12.9      M    M
 28000  -38.7 -37.7   295   62   32   9.3   5.1   30.5  86.9    12.8      M    M
 27000  -35.9 -32.6   295   59   30   9.3   5.1   30.4  86.6    12.9      M    M
 26000  -33.1 -27.6   295   57   29   9.3   5.1   30.3  86.5    13.0      M    M
 25000  -30.3 -22.5   295   54   28   9.3   5.1   30.4  86.6    13.2      M    M
 24000  -27.5 -17.5   295   50   26   9.0   4.9   30.1  86.1    13.1      M    M
 23000  -24.9 -12.8   295   48   25   8.7   4.8   29.7  85.5    13.0      M    M
 22000  -22.3  -8.1   295   49   25   8.7   4.8   29.3  84.7    12.7      M    M
 21000  -19.8  -3.6   300   49   25   8.7   4.8   28.9  84.0    12.5      M    M
 20000  -17.2   1.0   300   50   26   8.7   4.8   28.6  83.5    12.4      M    M
 19500  -15.9   3.4   300   52   27   9.2   5.0   28.4  83.1    12.3      M    M
 19000  -14.9   5.2   295   55   28   0.8   0.4   27.8  82.0    11.8      M    M
 18500  -15.1   4.8   295   58   30  -1.4  -0.8   26.0  78.7    10.3      M    M
 18000  -15.6   3.9   295   59   31   0.1   0.1   23.7  74.7     8.3      M    M
 17500  -14.7   5.5   290   61   31   8.7   4.8   23.1  73.6     7.9      M    M
 17000  -12.8   9.0   290   63   32   8.4   4.6   22.8  73.0     7.6      M    M
 16500  -11.5  11.3   285   65   33   8.2   4.5   22.6  72.6     7.4      M    M
 16000  -10.3  13.5   285   66   34   4.2   2.3   22.4  72.2     7.3      M    M
 15500   -9.8  14.4   285   67   34   4.2   2.3   21.0  69.8     6.3      M    M
 15000   -9.1  15.6   285   66   34   3.0   1.6   20.1  68.3     5.6      M    M
 14500   -8.9  16.0   285   62   32   1.9   1.0   18.8  65.8     4.4      M    M
 14000   -8.7  16.3   285   57   30   1.8   1.0   17.5  63.5     3.2      M    M
 13500   -8.1  17.4   285   54   28   7.7   4.2   16.6  61.8     2.2      M    M
 13000   -6.9  19.6   285   51   26   8.3   4.5   16.3  61.4     2.0      M    M
 12500   -5.7  21.7   285   47   24   8.3   4.6   16.1  61.0     1.8      M    M
 12000   -4.4  24.1   285   43   22   8.3   4.6   15.9  60.6     1.6      M    M
 11500   -3.2  26.2   285   38   20   8.3   4.6   15.6  60.1     1.3      M    M
 11000   -2.0  28.4   285   33   17   8.3   4.6   15.4  59.7     1.1      M    M
 10500   -0.7  30.7   290   28   15   8.3   4.6   15.2  59.3     0.9      M    M
 10250   -0.1  31.8   290   26   13   8.3   4.6   15.1  59.1     0.8      M    M
 10000    0.5  32.9   290   24   12   7.8   4.3   14.9  58.9     0.7      M    M
  9750    1.0  33.8   290   22   11   7.3   4.0   14.8  58.6     0.5      M    M
  9500    1.6  34.9   290   20   10   7.5   4.1   14.6  58.3     0.3      M    M
  9250    2.1  35.8   285   18    9   7.4   4.1   14.4  58.0     0.1      M    M
  9000    2.7  36.9   285   16    8   7.5   4.1   14.3  57.7    -0.0    250  1.3
  8750    3.2  37.8   285   14    7   7.5   4.1   14.1  57.3    -0.2    226  1.1
  8500    3.8  38.8   280   12    6   7.5   4.1   13.9  57.0    -0.4    202  1.0
  8250    4.3  39.7   275   11    5   7.5   4.1   13.7  56.7    -0.6    178  0.9
  8000    4.9  40.8   270    9    5   7.5   4.1   13.6  56.4    -0.8    154  0.8
  7750    5.4  41.7   245    7    4   7.5   4.1   13.4  56.1    -1.0    130  0.7
  7500    6.0  42.8   215    7    4   7.3   4.0   13.2  55.8    -1.1    106  0.5
  7250    6.5  43.7   190    9    5   8.0   4.4   13.0  55.4    -1.3     83  0.4
  7000    7.1  44.8   175   12    6   5.4   3.0   12.9  55.1    -1.5     59  0.3
  6750    7.6  45.7   175   10    5  15.1   8.3   12.7  54.8    -1.7     35  0.2
  6500    8.2  46.8   175    9    4 -21.1 -11.6   12.5  54.5    -1.9     11  0.1
  6250    4.5  40.1   175    7    4 -53.2 -29.2    8.1  46.6    -6.3    113  0.6
  6000    0.7  33.3   175    5    3 -63.7 -35.0    3.5  38.3   -10.9    222  1.1
  5750   -4.4  24.1   175    2    1 -53.5 -29.4   -2.5  27.5   -16.8    367  1.9
  5500   -5.5  22.1   355    1    0  27.4  15.0   -4.3  24.3   -18.6    390  2.0

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

           12/10/2016 at 0800 MST          |       12/10/2016 at 1100 MST
                                           |
CAPE...     0.0    LI...       +6.6        | CAPE...     0.0    LI...       +7.2
CINH...    -0.5    K Index...  +3.3        | CINH...     0.0    K Index...  +5.5
                                           |
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 -62.1 -79.8  320  50 26  -4.4  -2.4 | -62.7 -80.9  315  44 23  -4.6  -2.5
 45000 -68.7 -91.7  310  50 26  -4.3  -2.3 | -69.5 -93.1  300  43 22  -4.4  -2.4
 40000 -67.3 -89.1  330  68 35   1.5   0.8 | -66.4 -87.5  325  58 30   2.6   1.4
 38000 -64.7 -84.5  335  72 37   7.4   4.1 | -63.6 -82.5  325  62 32   6.8   3.8
 36000 -60.3 -76.5  330  69 36   7.4   4.1 | -59.5 -75.1  325  60 31   6.8   3.8
 34000 -55.6 -68.1  330  66 34   9.7   5.3 | -55.1 -67.2  325  58 30   9.4   5.1
 32000 -49.9 -57.8  330  61 31   9.5   5.2 | -49.5 -57.1  325  54 28   9.3   5.1
 30000 -44.2 -47.6  330  56 29   9.2   5.1 | -43.3 -45.9  325  51 26   9.4   5.1
 29000 -40.8 -41.4  325  51 26   9.3   5.1 | -40.5 -40.9  325  50 26   9.3   5.1
 28000 -38.0 -36.4  325  48 25   9.3   5.1 | -37.7 -35.9  320  49 25   9.3   5.1
 27000 -35.2 -31.4  320  45 23   8.9   4.9 | -34.9 -30.8  320  47 24   9.1   5.0
 26000 -32.6 -26.7  320  40 21   8.8   4.8 | -32.2 -26.0  320  45 23   9.1   5.0
 25000 -30.0 -22.0  310  36 19   8.8   4.8 | -29.5 -21.1  320  42 22   9.1   5.0
 24000 -27.4 -17.3  305  32 17   8.5   4.7 | -26.8 -16.2  315  39 20   8.9   4.9
 23000 -24.9 -12.8  300  31 16   8.1   4.5 | -24.2 -11.6  315  37 19   8.7   4.8
 22000 -22.5  -8.5  295  30 15   8.1   4.5 | -21.6  -6.9  310  34 18   8.7   4.8
 21000 -20.1  -4.2  285  29 15   7.3   4.0 | -19.1  -2.4  310  32 16   7.8   4.3
 20000 -18.0  -0.4  285  29 15   7.1   3.9 | -16.8   1.8  305  31 16   7.6   4.2
 19500 -17.0   1.4  285  29 15   7.1   3.9 | -15.7   3.7  305  31 16   7.6   4.2
 19000 -15.9   3.4  285  29 15   7.0   3.9 | -14.6   5.7  300  30 16   7.6   4.2
 18500 -14.9   5.2  280  29 15   6.8   3.7 | -13.5   7.7  300  30 15   7.2   4.0
 18000 -13.9   7.0  280  29 15   6.6   3.6 | -12.5   9.5  300  30 15   6.8   3.7
 17500 -13.0   8.6  285  29 15   6.6   3.6 | -11.5  11.3  295  30 16   6.8   3.7
 17000 -12.0  10.4  285  29 15   6.1   3.4 | -10.5  13.1  295  30 16   6.0   3.3
 16500 -11.1  12.0  285  30 15   6.2   3.4 |  -9.2  15.4  290  31 16   6.1   3.3
 16000  -9.7  14.5  285  30 15   6.1   3.3 |  -8.3  17.1  290  31 16   5.7   3.1
 15500  -8.8  16.2  290  30 15   6.1   3.3 |  -7.5  18.5  290  32 16   5.8   3.2
 15000  -7.9  17.8  290  30 15   6.1   3.3 |  -6.6  20.1  285  32 16   5.4   2.9
 14500  -7.0  19.4  290  30 15   6.1   3.3 |  -5.9  21.4  285  32 17   5.3   2.9
 14000  -6.1  21.0  295  30 15   5.9   3.2 |  -5.1  22.8  285  32 17   5.1   2.8
 13500  -5.3  22.5  295  29 15   5.8   3.2 |  -4.3  24.3  280  32 16   5.0   2.8
 13000  -4.4  24.1  295  29 15   5.8   3.2 |  -3.6  25.5  280  31 16   4.9   2.7
 12500  -3.6  25.5  300  28 14   5.7   3.1 |  -2.9  26.8  280  30 15   4.6   2.5
 12000  -2.7  27.1  300  27 14   5.6   3.1 |  -2.2  28.0  280  29 15   4.6   2.5
 11500  -1.9  28.6  300  25 13   5.5   3.0 |  -1.5  29.3  280  26 14   4.9   2.7
 11000  -1.1  30.0  305  24 12   5.5   3.0 |  -0.8  30.6  280  24 12   4.9   2.7
 10500  -0.3  31.5  310  22 11   5.4   2.9 |  -0.1  31.8  275  21 11   5.2   2.9
 10250   0.1  32.2  315  22 11   5.5   3.0 |   0.3  32.5  275  19 10   5.3   2.9
 10000   0.5  32.9  315  20 10   6.2   3.4 |   0.7  33.3  275  17  9   6.1   3.3
  9750   1.0  33.8  315  18  9   6.5   3.6 |   1.2  34.2  275  16  8   6.6   3.6
  9500   1.5  34.7  315  17  9   6.4   3.5 |   1.7  35.1  275  14  7   6.7   3.7
  9250   1.9  35.4  320  16  8   6.3   3.5 |   2.2  36.0  275  12  6   6.2   3.4
  9000   2.4  36.3  325  16  8   6.8   3.7 |   2.7  36.9  270  11  6   7.9   4.3
  8750   2.9  37.2  335  18  9   7.2   3.9 |   3.3  37.9  270   9  4   8.5   4.6
  8500   3.5  38.3  340  16  8   7.0   3.9 |   3.9  39.0  265   8  4   7.2   4.0
  8250   4.0  39.2  340  14  7   7.3   4.0 |   4.5  40.1  260   6  3   7.6   4.2
  8000   4.6  40.3  350  17  9   8.2   4.5 |   5.0  41.0  255   5  3   8.1   4.5
  7750   5.2  41.4  355  23 12   8.3   4.5 |   5.7  42.3  245   4  2   8.3   4.6
  7500   5.8  42.4  355  16  8   8.0   4.4 |   6.3  43.3  215   5  3   8.0   4.4
  7250   6.4  43.5  355   9  5   7.7   4.2 |   6.9  44.4  200   7  4   8.2   4.5
  7000   7.0  44.6  360  27 14   8.1   4.4 |   7.5  45.5  190   8  4   8.6   4.7
  6750   7.5  45.5  360  45 23   4.5   2.4 |   8.1  46.6  180  10  5   7.2   3.9
  6500   7.6  45.7  180   7  4  -1.3  -0.7 |   8.6  47.5  180  23 12   6.5   3.6
  6250   7.2  45.0  180  42 22  -9.4  -5.2 |   9.0  48.2  180  34 18   2.0   1.1
  6000   6.2  43.2  180  46 24 -15.1  -8.3 |   8.9  48.0  180  32 16  -2.2  -1.2
  5750   5.2  41.4  180  49 25 -12.0  -6.6 |   8.8  47.8  175  30 15  -1.0  -0.5
  5500   3.7  38.7  180  64 33 -34.3 -18.8 |   8.4  47.1  180  53 27 -10.7  -5.8

           12/10/2016 at 1400 MST          |       12/10/2016 at 1700 MST
                                           |
CAPE...     0.0    LI...       +4.7        | CAPE...     0.0    LI...       +4.8
CINH...    -0.1    K Index... +11.4        | CINH...    -0.2    K Index... +11.3
                                           |
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 -63.5 -82.3  310  44 23  -3.9  -2.2 | -64.9 -84.8  305  47 24  -2.5  -1.4
 45000 -69.4 -92.9  290  40 21  -4.3  -2.3 | -68.7 -91.7  305  45 23  -2.9  -1.6
 40000 -65.9 -86.6  320  54 28   2.8   1.6 | -65.5 -85.9  320  58 30   2.4   1.3
 38000 -63.1 -81.6  325  59 30   7.0   3.8 | -62.8 -81.0  320  60 31   7.1   3.9
 36000 -58.4 -73.1  320  56 29   7.0   3.8 | -58.1 -72.6  315  55 28   7.1   3.9
 34000 -54.0 -65.2  315  53 27   8.7   4.8 | -53.5 -64.3  315  50 26   8.9   4.9
 32000 -48.7 -55.7  310  46 24   8.8   4.8 | -48.1 -54.6  310  44 23   9.0   4.9
 30000 -43.3 -45.9  310  40 21   9.1   5.0 | -42.7 -44.9  300  38 20   9.0   4.9
 29000 -40.6 -41.1  305  37 19   9.1   5.0 | -40.0 -40.0  300  36 18   8.9   4.9
 28000 -37.9 -36.2  305  35 18   9.1   5.0 | -37.4 -35.3  295  33 17   8.9   4.9
 27000 -35.1 -31.2  300  32 17   9.0   4.9 | -34.7 -30.5  290  31 16   8.8   4.8
 26000 -32.5 -26.5  300  31 16   8.9   4.9 | -32.1 -25.8  290  30 15   8.7   4.8
 25000 -29.8 -21.6  295  30 15   8.9   4.9 | -29.5 -21.1  285  28 15   8.7   4.8
 24000 -27.2 -17.0  295  28 15   8.8   4.8 | -26.9 -16.4  285  27 14   8.7   4.8
 23000 -24.6 -12.3  290  28 14   8.5   4.7 | -24.3 -11.7  285  26 14   8.5   4.7
 22000 -22.1  -7.8  290  27 14   8.5   4.7 | -21.8  -7.2  285  26 13   8.5   4.7
 21000 -19.5  -3.1  290  27 14   8.2   4.5 | -19.3  -2.7  285  25 13   8.2   4.5
 20000 -16.6   2.1  290  27 14   8.0   4.4 | -16.9   1.6  285  26 13   7.9   4.3
 19500 -15.4   4.3  290  27 14   8.0   4.4 | -15.7   3.7  285  26 13   7.9   4.3
 19000 -14.2   6.4  290  27 14   8.1   4.4 | -14.0   6.8  285  26 13   8.0   4.4
 18500 -13.0   8.6  290  28 14   7.5   4.1 | -12.8   9.0  285  26 13   7.4   4.1
 18000 -11.9  10.6  290  28 14   7.4   4.0 | -11.7  10.9  290  26 14   7.3   4.0
 17500 -10.8  12.6  290  28 15   7.3   4.0 | -10.6  12.9  290  27 14   7.2   4.0
 17000  -9.8  14.4  290  29 15   7.1   3.9 |  -9.6  14.7  295  27 14   6.9   3.8
 16500  -8.7  16.3  290  29 15   7.1   3.9 |  -8.6  16.5  295  28 14   6.9   3.8
 16000  -7.7  18.1  295  29 15   6.6   3.6 |  -7.6  18.3  295  29 15   6.7   3.7
 15500  -6.7  19.9  295  30 15   6.6   3.6 |  -6.6  20.1  300  30 15   6.7   3.7
 15000  -5.8  21.6  295  30 15   6.5   3.5 |  -5.6  21.9  300  30 16   6.6   3.6
 14500  -4.8  23.4  295  30 15   6.4   3.5 |  -4.6  23.7  305  31 16   6.4   3.5
 14000  -3.9  25.0  295  30 16   6.2   3.4 |  -3.7  25.3  305  32 16   6.3   3.5
 13500  -3.1  26.4  290  30 16   5.7   3.1 |  -2.8  27.0  305  33 17   6.0   3.3
 13000  -2.2  28.0  290  30 15   5.7   3.1 |  -1.9  28.6  305  34 17   6.0   3.3
 12500  -1.4  29.5  290  30 15   5.3   2.9 |  -1.1  30.0  310  34 18   5.4   2.9
 12000  -0.6  30.9  285  29 15   5.3   2.9 |  -0.3  31.5  310  34 18   5.4   3.0
 11500   0.1  32.2  280  28 14   5.1   2.8 |   0.5  32.9  310  34 17   5.2   2.9
 11000   0.9  33.6  280  26 13   5.1   2.8 |   1.2  34.2  305  33 17   5.3   2.9
 10500   1.5  34.7  275  24 13   3.9   2.1 |   1.9  35.4  305  32 16   3.3   1.8
 10250   1.9  35.4  275  23 12   4.7   2.6 |   2.1  35.8  305  31 16   4.2   2.3
 10000   2.3  36.1  270  22 12   6.5   3.5 |   2.5  36.5  305  30 15   6.0   3.3
  9750   2.8  37.0  270  21 11   6.6   3.6 |   2.9  37.2  300  28 14   5.9   3.3
  9500   3.2  37.8  265  20 10   6.0   3.3 |   3.3  37.9  300  26 13   5.1   2.8
  9250   3.7  38.7  265  18  9   6.2   3.4 |   3.7  38.7  295  24 12   5.3   2.9
  9000   4.1  39.4  265  17  9   6.0   3.3 |   4.1  39.4  295  23 12   5.1   2.8
  8750   4.6  40.3  255  16  8   6.6   3.6 |   4.5  40.1  295  21 11   5.8   3.2
  8500   5.1  41.2  250  15  8   7.4   4.0 |   5.0  41.0  290  19 10   6.5   3.6
  8250   5.7  42.3  245  14  7   7.2   3.9 |   5.4  41.7  285  17  9   6.4   3.5
  8000   6.2  43.2  245  13  7   7.3   4.0 |   5.9  42.6  280  15  8   6.1   3.4
  7750   6.8  44.2  245  11  6   7.8   4.3 |   6.4  43.5  275  14  7   6.8   3.7
  7500   7.4  45.3  235  11  6   8.2   4.5 |   6.9  44.4  270  12  6   7.6   4.2
  7250   8.0  46.4  225  12  6   8.1   4.4 |   7.5  45.5  260  11  6   7.4   4.1
  7000   8.6  47.5  220  11  6   8.6   4.7 |   8.0  46.4  250  10  5   6.8   3.7
  6750   9.3  48.7  215   9  5   8.5   4.7 |   8.5  47.3  245   9  4   7.2   3.9
  6500   9.9  49.8  200  15  8   8.2   4.5 |   9.1  48.4  225   9  4   8.4   4.6
  6250  10.5  50.9  190  21 11   8.0   4.4 |   9.7  49.5  210   9  5   7.0   3.9
  6000  11.1  52.0  185  32 17   7.4   4.1 |  10.1  50.2  190  17  9   4.3   2.3
  5750  11.7  53.1  180  45 23   7.6   4.2 |  10.5  50.9  180  29 15   5.7   3.1
  5500  12.1  53.8  180  56 29   1.2   0.6 |  10.5  50.9  180  32 17 -13.0  -7.1
________________________________________________________________________________

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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