Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 041333
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0633 MST Monday, December 4, 2017

This forecast is for Monday, December 4, 2017:

If the trigger temperature of 42.5 F/5.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7333 ft MSL (2017 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. None
Thermal soaring outlook for Tuesday 12/05...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak NVA
Potential height of wave....................... 52845 ft MSL (47529 ft AGL)
Wave soaring outlook for Tuesday 12/05......... Poor

Remarks...

Sunrise/Sunset.................... 07:04:53 / 16:34:54 MST
Total possible sunshine........... 9 hr 30 min 1 sec (570 min 1 sec)
Altitude of sun at 11:49:54 MST... 27.86 degrees

Upper air data from numerical model forecast valid on 12/04/2017 at 0500 MST

Freezing level.................. 6731 ft MSL (1415 ft AGL)
Convective condensation level... 16911 ft MSL (11595 ft AGL)
Lifted condensation level....... 13105 ft MSL (7789 ft AGL)
Lifted index.................... +11.1
K index......................... -9.3

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   245   35   18   1.3   0.7      M     M       M      M    M
 45000  -56.4 -69.5   240   39   20   1.3   0.7      M     M       M      M    M
 40000  -53.7 -64.7   250   36   19   1.8   1.0      M     M       M      M    M
 38000  -52.5 -62.5   250   36   18   3.2   1.8      M     M       M      M    M
 36000  -50.6 -59.1   250   37   19   3.2   1.7      M     M       M      M    M
 34000  -48.5 -55.3   250   38   20   3.2   1.7      M     M       M      M    M
 32000  -46.5 -51.7   250   39   20   3.3   1.8      M     M       M      M    M
 30000  -44.5 -48.1   250   40   21   3.3   1.8      M     M       M      M    M
 29000  -43.2 -45.8   250   41   21   4.5   2.5   30.9  87.6    20.0      M    M
 28000  -41.9 -43.4   250   41   21   4.5   2.5   28.7  83.7    18.6      M    M
 27000  -40.5 -40.9   250   41   21   4.5   2.5   26.8  80.2    17.3      M    M
 26000  -39.0 -38.2   250   41   21   6.5   3.6   25.0  77.1    16.2      M    M
 25000  -37.1 -34.8   250   42   22   6.3   3.5   23.7  74.6    15.3      M    M
 24000  -35.2 -31.4   250   42   22   6.3   3.5   22.4  72.3    14.5      M    M
 23000  -33.2 -27.8   250   42   22   7.4   4.0   21.3  70.3    13.7      M    M
 22000  -31.1 -24.0   250   42   21   7.3   4.0   20.3  68.5    13.1      M    M
 21000  -28.9 -20.0   250   41   21   7.2   4.0   19.4  67.0    12.5      M    M
 20000  -26.8 -16.2   250   40   21   6.7   3.7   18.5  65.3    11.8      M    M
 19500  -25.8 -14.4   250   40   20   6.7   3.7   17.9  64.2    11.4      M    M
 19000  -24.7 -12.5   250   39   20   6.7   3.7   17.4  63.3    11.1      M    M
 18500  -23.7 -10.7   250   39   20   6.7   3.7   16.9  62.4    10.7      M    M
 18000  -22.7  -8.9   250   38   20   6.6   3.6   16.4  61.5    10.3      M    M
 17500  -21.3  -6.3   250   36   18   6.0   3.3   15.5  59.8     9.6      M    M
 17000  -20.4  -4.7   250   34   17   5.7   3.1   14.9  58.7     9.1      M    M
 16500  -19.7  -3.5   250   32   16   5.2   2.9   14.1  57.3     8.5      M    M
 16000  -18.9  -2.0   250   30   15   5.2   2.9   13.3  56.0     7.8      M    M
 15500  -18.2  -0.8   250   29   15   3.9   2.1   12.4  54.4     7.1      M    M
 15000  -17.6   0.3   255   27   14   4.0   2.2   11.5  52.6     6.2      M    M
 14500  -17.0   1.4   255   26   13   4.2   2.3   10.5  50.9     5.4      M    M
 14000  -16.4   2.5   255   25   13   4.1   2.2    9.6  49.3     4.6      M    M
 13500  -15.7   3.7   255   23   12   6.3   3.5    8.8  47.9     3.9      M    M
 13000  -14.7   5.5   255   22   11   6.6   3.6    8.3  46.9     3.4      M    M
 12500  -13.7   7.3   255   21   11   7.3   4.0    7.8  46.1     3.0      M    M
 12000  -12.6   9.3   260   20   10   7.4   4.0    7.4  45.4     2.6      M    M
 11500  -11.5  11.3   260   19   10   8.1   4.4    7.1  44.8     2.3      M    M
 11000  -10.2  13.6   260   19   10   8.3   4.5    6.9  44.3     2.1      M    M
 10500   -9.0  15.8   265   19   10   7.5   4.1    6.6  43.8     1.8      M    M
 10250   -8.5  16.7   265   18    9   6.4   3.5    6.4  43.5     1.6      M    M
 10000   -8.0  17.6   265   18    9  10.0   5.5    6.2  43.1     1.5      M    M
  9750   -7.1  19.2   270   19   10  10.6   5.8    6.3  43.4     1.6      M    M
  9500   -6.5  20.3   270   19   10   6.9   3.8    6.2  43.1     1.5      M    M
  9250   -6.0  21.2   275   19   10   7.0   3.8    6.0  42.7     1.3      M    M
  9000   -5.4  22.3   275   20   10   7.7   4.2    5.8  42.4     1.1      M    M
  8750   -4.8  23.4   280   20   10   7.9   4.4    5.6  42.2     0.9      M    M
  8500   -4.3  24.3   280   20   10   7.2   3.9    5.5  41.8     0.8      M    M
  8250   -3.7  25.3   280   20   10   7.7   4.2    5.3  41.5     0.6      M    M
  8000   -3.2  26.2   280   20   10   6.4   3.5    5.1  41.2     0.4      M    M
  7750   -2.7  27.1   285   20   10   7.4   4.1    4.8  40.7     0.1      M    M
  7500   -2.1  28.2   285   20   10   9.4   5.1    4.8  40.6     0.1      M    M
  7250   -1.4  29.5   285   19   10   9.0   4.9    4.7  40.5    -0.0     78  0.4
  7000   -0.8  30.6   285   19   10   7.8   4.3    4.6  40.3    -0.1     51  0.3
  6750   -0.2  31.6   285   19   10   8.9   4.9    4.5  40.0    -0.3     27  0.1
  6500    0.6  33.1   290   18    9  11.2   6.2    4.5  40.1    -0.2      M    M
  6250    1.4  34.5   290   16    8   9.7   5.3    4.6  40.3    -0.2      M    M
  6000    2.0  35.6   290   15    8   8.0   4.4    4.5  40.1    -0.2      M    M
  5750    2.6  36.7   290   14    7   8.9   4.9    4.4  39.9    -0.4      M    M
  5500    3.3  37.9   290   11    6   9.4   5.1    4.4  39.9    -0.4      M    M

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

           12/04/2017 at 0800 MST          |       12/04/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +4.5        | CAPE...     0.0    LI...       +3.4
CINH...    -0.2    K Index...  -3.0        | CINH...    -0.1    K Index...  +7.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -55.2 -67.4  250  32 16  -0.4  -0.2 | -54.9 -66.8  255  28 15   0.7   0.4
 45000 -55.9 -68.6  245  41 21  -0.4  -0.2 | -53.9 -65.0  250  37 19   0.7   0.4
 40000 -53.1 -63.6  250  40 20   2.2   1.2 | -51.2 -60.2  255  39 20   1.9   1.1
 38000 -51.8 -61.2  250  39 20   2.5   1.4 | -50.1 -58.2  255  39 20   1.3   0.7
 36000 -50.3 -58.5  255  39 20   2.5   1.4 | -49.2 -56.6  260  40 21   1.3   0.7
 34000 -48.8 -55.8  255  40 20   2.5   1.4 | -48.5 -55.3  260  41 21   1.2   0.7
 32000 -46.6 -51.9  255  39 20   3.5   1.9 | -47.2 -53.0  260  41 21   2.3   1.3
 30000 -44.5 -48.1  255  39 20   3.4   1.9 | -45.8 -50.4  265  41 21   2.3   1.3
 29000 -43.2 -45.8  255  39 20   4.5   2.5 | -44.8 -48.6  265  41 21   3.9   2.2
 28000 -41.9 -43.4  260  39 20   4.5   2.5 | -43.6 -46.5  265  40 21   4.0   2.2
 27000 -40.5 -40.9  260  39 20   4.5   2.5 | -42.4 -44.3  265  39 20   4.0   2.2
 26000 -39.2 -38.6  260  38 20   5.0   2.8 | -41.2 -42.2  265  38 20   4.0   2.2
 25000 -37.6 -35.7  260  37 19   5.1   2.8 | -40.0 -40.0  270  34 18   4.1   2.2
 24000 -36.1 -33.0  260  36 19   5.1   2.8 | -38.8 -37.8  270  31 16   4.1   2.2
 23000 -34.6 -30.3  265  35 18   4.9   2.7 | -37.5 -35.5  275  27 14   4.5   2.5
 22000 -33.2 -27.8  265  32 17   4.9   2.7 | -36.1 -33.0  280  21 11   4.8   2.6
 21000 -31.7 -25.1  270  30 15   4.9   2.7 | -34.7 -30.5  285  15  8   4.8   2.6
 20000 -30.3 -22.5  270  26 13   4.6   2.5 | -33.1 -27.6  295  12  6   6.7   3.7
 19500 -29.6 -21.3  275  24 12   4.6   2.5 | -31.6 -24.9  305  12  6   6.6   3.6
 19000 -28.9 -20.0  275  21 11   4.6   2.5 | -30.6 -23.1  310  11  6   6.6   3.6
 18500 -28.2 -18.8  280  19 10   4.6   2.5 | -29.6 -21.3  315  11  6   6.6   3.6
 18000 -27.5 -17.5  285  17  9   4.7   2.6 | -28.6 -19.5  320  12  6   7.1   3.9
 17500 -26.4 -15.5  290  15  8   5.1   2.8 | -27.5 -17.5  325  12  6   7.2   4.0
 17000 -25.7 -14.3  300  13  7   5.3   2.9 | -26.4 -15.5  330  13  7   6.9   3.8
 16500 -24.8 -12.6  305  13  7   5.8   3.2 | -25.4 -13.7  330  13  7   6.5   3.6
 16000 -24.0 -11.2  315  14  7   5.7   3.1 | -24.5 -12.1  330  14  7   6.4   3.5
 15500 -23.0  -9.4  320  15  8   7.0   3.8 | -23.6 -10.5  330  15  8   5.7   3.2
 15000 -22.0  -7.6  320  16  8   6.7   3.7 | -22.7  -8.9  335  15  8   5.7   3.1
 14500 -20.9  -5.6  320  17  9   8.4   4.6 | -21.8  -7.2  335  15  8   7.1   3.9
 14000 -19.6  -3.3  320  18  9   8.4   4.6 | -20.8  -5.4  335  15  8   6.9   3.8
 13500 -18.4  -1.1  320  20 10   8.5   4.7 | -19.7  -3.5  335  15  8   7.5   4.1
 13000 -17.1   1.2  320  21 11   8.5   4.7 | -18.6  -1.5  335  15  8   7.5   4.1
 12500 -15.9   3.4  320  22 11   8.1   4.5 | -17.5   0.5  335  15  8   7.5   4.1
 12000 -14.7   5.5  320  22 12   8.1   4.4 | -16.4   2.5  335  15  8   7.5   4.1
 11500 -13.5   7.7  315  23 12   7.8   4.3 | -15.2   4.6  340  15  8   7.4   4.0
 11000 -12.3   9.9  315  23 12   7.9   4.3 | -14.1   6.6  340  15  8   7.4   4.0
 10500 -11.2  11.8  310  24 12   7.2   3.9 | -13.0   8.6  340  15  8   7.6   4.2
 10250 -10.7  12.7  310  24 12   6.7   3.7 | -12.5   9.5  340  15  8   7.4   4.1
 10000 -10.1  13.8  310  24 12   8.2   4.5 | -11.9  10.6  340  15  8   8.0   4.4
  9750  -9.5  14.9  305  24 13   8.5   4.6 | -11.3  11.7  345  15  8   8.7   4.8
  9500  -8.9  16.0  305  24 12   7.2   4.0 | -10.6  12.9  345  15  8   8.7   4.8
  9250  -8.4  16.9  305  24 12   7.2   4.0 | -10.0  14.0  345  14  7   8.7   4.8
  9000  -7.8  18.0  300  24 12   8.2   4.5 |  -9.3  15.3  345  14  7   8.5   4.7
  8750  -7.2  19.0  300  24 12   7.6   4.2 |  -8.7  16.3  345  14  7   9.1   5.0
  8500  -6.7  19.9  300  23 12   6.1   3.4 |  -8.0  17.6  345  14  7   9.7   5.3
  8250  -6.2  20.8  295  23 12   6.6   3.6 |  -7.2  19.0  350  14  7   9.5   5.2
  8000  -5.7  21.7  295  22 11   6.1   3.4 |  -6.5  20.3  350  14  7   9.6   5.3
  7750  -5.3  22.5  295  22 11   7.3   4.0 |  -5.8  21.6  350  14  7   9.7   5.3
  7500  -4.7  23.5  290  21 11   8.5   4.7 |  -5.1  22.8  350  13  7   9.7   5.3
  7250  -4.0  24.8  290  20 10   8.1   4.5 |  -4.3  24.3  350  13  7   9.8   5.4
  7000  -3.5  25.7  290  19 10   7.0   3.9 |  -3.6  25.5  350  13  7   9.6   5.3
  6750  -2.9  26.8  290  19 10   8.3   4.5 |  -2.9  26.8  355  13  7  10.2   5.6
  6500  -2.2  28.0  290  17  9  10.6   5.8 |  -2.1  28.2  350  13  7  10.7   5.9
  6250  -1.5  29.3  285  16  8   8.9   4.9 |  -1.3  29.7  355  12  6  10.3   5.7
  6000  -0.9  30.4  285  14  7   7.4   4.0 |  -0.5  31.1  355  12  6  10.0   5.5
  5750  -0.3  31.5  285  13  7   8.6   4.7 |   0.2  32.4  355  12  6  11.0   6.1
  5500   0.4  32.7  285  11  5   9.6   5.3 |   1.2  34.2  355  10  5  17.0   9.3

           12/04/2017 at 1400 MST          |       12/04/2017 at 1700 MST
                                           |
CAPE...     0.0    LI...       +3.0        | CAPE...     0.0    LI...       +1.9
CINH...    -0.1    K Index...  +6.3        | CINH...    -0.1    K Index...  +9.6
                                           |
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 -56.0 -68.8  260  27 14   1.5   0.8 | -56.6 -69.9  265  27 14   2.0   1.1
 45000 -53.7 -64.7  260  35 18   1.5   0.8 | -53.6 -64.5  265  33 17   2.0   1.1
 40000 -51.3 -60.3  260  38 20   1.6   0.9 | -51.3 -60.3  265  37 19   1.4   0.8
 38000 -50.4 -58.7  260  39 20   0.9   0.5 | -50.5 -58.9  265  39 20   1.1   0.6
 36000 -49.8 -57.6  260  40 21   0.9   0.5 | -49.8 -57.6  265  41 21   1.1   0.6
 34000 -49.3 -56.7  260  41 21   0.8   0.5 | -49.1 -56.4  265  42 22   1.0   0.6
 32000 -48.1 -54.6  260  41 21   2.2   1.2 | -48.0 -54.4  265  42 22   2.1   1.2
 30000 -46.8 -52.2  265  41 21   2.2   1.2 | -46.7 -52.1  265  41 21   2.0   1.1
 29000 -45.7 -50.3  265  41 21   4.2   2.3 | -45.8 -50.4  265  40 21   3.5   1.9
 28000 -44.5 -48.1  265  40 20   4.3   2.3 | -44.8 -48.6  265  39 20   3.5   1.9
 27000 -43.2 -45.8  265  39 20   4.3   2.3 | -43.7 -46.7  265  37 19   3.5   1.9
 26000 -41.9 -43.4  265  38 19   4.8   2.6 | -42.6 -44.7  265  35 18   4.8   2.6
 25000 -40.4 -40.7  265  35 18   4.9   2.7 | -41.1 -42.0  265  33 17   4.9   2.7
 24000 -38.9 -38.0  270  32 16   4.9   2.7 | -39.6 -39.3  265  31 16   4.9   2.7
 23000 -37.5 -35.5  270  29 15   4.5   2.5 | -38.2 -36.8  265  28 15   4.8   2.6
 22000 -36.2 -33.2  270  24 12   4.4   2.4 | -36.8 -34.2  270  26 13   4.7   2.6
 21000 -34.8 -30.6  265  19 10   4.5   2.5 | -35.3 -31.5  270  23 12   4.8   2.6
 20000 -33.2 -27.8  270  15  7   6.8   3.7 | -33.2 -27.8  270  20 10   6.6   3.6
 19500 -31.7 -25.1  270  13  7   6.8   3.7 | -32.2 -26.0  270  19 10   6.6   3.6
 19000 -30.7 -23.3  270  12  6   6.8   3.7 | -31.2 -24.2  265  17  9   6.6   3.6
 18500 -29.7 -21.5  275  11  5   6.7   3.7 | -30.2 -22.4  265  16  8   6.5   3.6
 18000 -28.7 -19.7  275  10  5   7.5   4.1 | -29.2 -20.6  270  15  8   7.7   4.2
 17500 -27.6 -17.7  280  10  5   7.5   4.1 | -28.0 -18.4  270  15  8   7.7   4.2
 17000 -26.4 -15.5  285  10  5   7.6   4.2 | -26.9 -16.4  270  15  8   7.8   4.3
 16500 -25.3 -13.5  290  11  5   7.6   4.2 | -25.7 -14.3  275  14  7   7.8   4.3
 16000 -24.1 -11.4  290  11  6   7.6   4.1 | -24.6 -12.3  275  14  7   7.8   4.3
 15500 -23.1  -9.6  290  11  6   7.0   3.9 | -23.4 -10.1  280  13  7   7.7   4.2
 15000 -22.0  -7.6  295  11  6   7.1   3.9 | -22.3  -8.1  280  13  7   7.7   4.2
 14500 -21.0  -5.8  295  11  6   7.1   3.9 | -21.1  -6.0  285  12  6   7.9   4.4
 14000 -19.9  -3.8  295  11  6   7.1   3.9 | -19.9  -3.8  285  12  6   7.9   4.3
 13500 -18.9  -2.0  295  11  6   7.0   3.9 | -18.8  -1.8  290  12  6   7.8   4.3
 13000 -17.8  -0.0  295  10  5   7.1   3.9 | -17.6   0.3  290  11  6   7.9   4.3
 12500 -16.8   1.8  295  10  5   6.8   3.7 | -16.4   2.5  290  11  6   7.7   4.2
 12000 -15.8   3.6  300   9  5   6.9   3.8 | -15.3   4.5  290  10  5   7.8   4.3
 11500 -14.8   5.4  305   8  4   6.6   3.6 | -14.2   6.4  290  10  5   6.9   3.8
 11000 -13.8   7.2  315   8  4   6.6   3.6 | -13.2   8.2  290   9  4   6.9   3.8
 10500 -12.9   8.8  325   8  4   6.1   3.3 | -12.3   9.9  290   7  4   5.1   2.8
 10250 -12.4   9.7  335   8  4   5.8   3.2 | -11.9  10.6  295   6  3   5.2   2.8
 10000 -12.0  10.4  340   8  4   7.1   3.9 | -11.6  11.1  295   6  3   5.5   3.0
  9750 -11.4  11.5  350   9  4   7.4   4.1 | -11.1  12.0  300   5  2   4.9   2.7
  9500 -10.9  12.4  355   8  4   6.5   3.5 | -10.8  12.6  310   4  2   4.1   2.3
  9250 -10.4  13.3  360   9  4   6.7   3.7 | -10.5  13.1  320   4  2   4.0   2.2
  9000  -9.9  14.2  005   9  4   6.7   3.7 | -10.2  13.6  335   4  2   5.3   2.9
  8750  -9.3  15.3  010   9  5   8.5   4.7 |  -9.7  14.5  350   3  2   7.4   4.1
  8500  -8.6  16.5  010   9  5   9.7   5.3 |  -9.1  15.6  360   3  2   7.6   4.1
  8250  -7.9  17.8  010   9  5   9.4   5.2 |  -8.6  16.5  010   4  2   7.9   4.3
  8000  -7.2  19.0  010   9  5   9.5   5.2 |  -7.9  17.8  020   4  2   9.0   4.9
  7750  -6.5  20.3  010   9  5   9.6   5.3 |  -7.2  19.0  025   4  2   9.2   5.0
  7500  -5.8  21.6  015   9  5   9.8   5.4 |  -6.5  20.3  025   4  2   8.8   4.8
  7250  -5.0  23.0  015   9  5   9.8   5.4 |  -5.9  21.4  030   4  2   9.5   5.2
  7000  -4.3  24.3  015   9  5   9.9   5.5 |  -5.1  22.8  030   4  2  10.2   5.6
  6750  -3.6  25.5  015   9  5   9.8   5.4 |  -4.4  24.1  035   5  2   9.4   5.2
  6500  -2.8  27.0  015   9  4  10.0   5.5 |  -3.7  25.3  035   4  2   9.3   5.1
  6250  -2.0  28.4  015   8  4  10.8   5.9 |  -3.0  26.6  035   4  2   9.8   5.4
  6000  -1.2  29.8  015   8  4  10.7   5.9 |  -2.2  28.0  035   4  2  10.1   5.5
  5750  -0.4  31.3  015   8  4  11.5   6.3 |  -1.5  29.3  040   4  2   9.1   5.0
  5500   0.6  33.1  015   7  4  16.9   9.3 |  -0.9  30.4  040   3  2   7.4   4.0
________________________________________________________________________________

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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