Soaring Guidance
Issued by NWS Denver/Boulder, CO

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666
UXUS97 KBOU 221406
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0806 MDT Sunday, October 22, 2017

This forecast is for Sunday, October 22, 2017:

If the trigger temperature of 59.6 F/15.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 501 ft/min (2.5 m/s)
   Maximum height of thermals.................. 12563 ft MSL (7241 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... 1100 MDT
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................. 10754 ft MSL (5432 ft AGL)
Thermal soaring outlook for Monday 10/23....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No changes
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 35119 ft MSL (29797 ft AGL)
Wave soaring outlook for Monday 10/23.......... Fair

Remarks...

Sunrise/Sunset.................... 07:17:43 / 18:09:58 MDT
Total possible sunshine........... 10 hr 52 min 15 sec (652 min 15 sec)
Altitude of sun at 12:43:51 MDT... 38.78 degrees

Upper air data from numerical model forecast valid on 10/22/2017 at 0600 MDT

Freezing level.................. 11967 ft MSL (6645 ft AGL)
Convective condensation level... 21779 ft MSL (16457 ft AGL)
Lifted condensation level....... 17676 ft MSL (12354 ft AGL)
Lifted index.................... +7.7
K index......................... +5.3

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  -61.4 -78.5   310   23   12   0.4   0.2      M     M       M      M    M
 45000  -60.7 -77.3   315   30   16   1.2   0.7      M     M       M      M    M
 40000  -58.8 -73.8   330   29   15   0.9   0.5      M     M       M      M    M
 38000  -55.6 -68.1   330   34   17   6.2   3.4      M     M       M      M    M
 36000  -51.9 -61.4   330   40   21   6.2   3.4      M     M       M      M    M
 34000  -47.2 -53.0   330   43   22   7.8   4.3      M     M       M      M    M
 32000  -42.5 -44.5   330   41   21   7.8   4.3      M     M       M      M    M
 30000  -37.6 -35.7   330   39   20   8.5   4.6   38.4 101.1    13.0      M    M
 29000  -35.1 -31.2   330   37   19   8.5   4.7   37.9 100.2    12.8      M    M
 28000  -32.5 -26.5   330   36   19   8.5   4.7   37.5  99.5    12.6      M    M
 27000  -30.0 -22.0   330   35   18   8.2   4.5   36.9  98.5    12.3      M    M
 26000  -27.6 -17.7   325   33   17   8.2   4.5   36.3  97.3    11.9      M    M
 25000  -25.2 -13.4   325   31   16   8.2   4.5   35.7  96.3    11.6      M    M
 24000  -22.8  -9.0   325   30   15   7.6   4.2   35.1  95.2    11.3      M    M
 23000  -20.5  -4.9   325   28   15   7.6   4.2   34.3  93.7    10.7      M    M
 22000  -18.3  -0.9   320   27   14   7.6   4.2   33.5  92.4    10.2      M    M
 21000  -16.2   2.8   320   26   13   6.0   3.3   32.5  90.5     9.4      M    M
 20000  -14.4   6.1   320   24   12   6.0   3.3   31.1  88.1     8.3      M    M
 19500  -13.6   7.5   320   23   12   6.0   3.3   30.5  86.9     7.8      M    M
 19000  -12.7   9.1   320   23   12   6.0   3.3   29.9  85.8     7.3      M    M
 18500  -11.8  10.8   320   22   11   5.3   2.9   29.2  84.5     6.7      M    M
 18000  -10.7  12.7   325   21   11   5.3   2.9   28.0  82.5     5.8      M    M
 17500   -9.8  14.4   325   20   10   6.5   3.5   27.4  81.3     5.2      M    M
 17000   -8.8  16.2   325   19   10   6.4   3.5   26.8  80.2     4.7      M    M
 16500   -7.9  17.8   325   19   10   6.6   3.6   26.2  79.2     4.2      M    M
 16000   -6.9  19.6   325   18    9   6.7   3.7   25.7  78.3     3.8      M    M
 15500   -5.9  21.4   325   18    9   6.7   3.7   25.2  77.4     3.4      M    M
 15000   -4.9  23.2   330   17    9   6.6   3.6   24.7  76.5     2.9      M    M
 14500   -3.9  25.0   330   17    9   6.6   3.6   24.2  75.5     2.4      M    M
 14000   -3.0  26.6   330   16    8   5.8   3.2   23.6  74.4     1.9      M    M
 13500   -2.2  28.0   330   16    8   6.0   3.3   22.9  73.3     1.3      M    M
 13000   -1.4  29.5   330   15    8   4.6   2.5   22.2  72.0     0.6      M    M
 12500   -0.7  30.7   325   14    7   4.7   2.6   21.4  70.5    -0.2    494  2.5
 12000   -0.0  32.0   325   14    7   4.4   2.4   20.5  69.0    -0.9    459  2.3
 11500    0.6  33.1   320   13    7   4.5   2.4   19.7  67.4    -1.8    424  2.2
 11000    1.3  34.3   315   13    6   4.1   2.3   18.8  65.9    -2.6    390  2.0
 10500    1.9  35.4   310   12    6   4.3   2.4   17.9  64.3    -3.5    357  1.8
 10250    2.2  36.0   305   12    6   3.3   1.8   17.5  63.5    -3.9    341  1.7
 10000    2.4  36.3   300   12    6   3.5   1.9   16.9  62.5    -4.4    327  1.7
  9750    2.7  36.9   300   12    6   4.6   2.5   16.5  61.7    -4.8    310  1.6
  9500    3.1  37.6   295   12    6   4.5   2.5   16.1  61.0    -5.2    293  1.5
  9250    3.4  38.1   290   12    6   3.3   1.8   15.7  60.2    -5.7    276  1.4
  9000    3.6  38.5   290   12    6   3.1   1.7   15.1  59.2    -6.2    262  1.3
  8750    3.9  39.0   285   12    6   5.3   2.9   14.7  58.4    -6.6    245  1.2
  8500    4.4  39.9   285   12    6   5.8   3.2   14.4  57.9    -6.9    224  1.1
  8250    4.8  40.6   280   11    6   5.5   3.0   14.1  57.3    -7.3    204  1.0
  8000    5.2  41.4   280   10    5   5.5   3.0   13.7  56.7    -7.6    184  0.9
  7750    5.7  42.3   275   10    5   5.8   3.2   13.4  56.2    -7.9    163  0.8
  7500    6.1  43.0   270    9    5   6.7   3.7   13.1  55.6    -8.2    142  0.7
  7250    6.6  43.9   265    8    4   7.1   3.9   12.9  55.3    -8.4    119  0.6
  7000    7.2  45.0   260    7    4   7.7   4.3   12.7  54.9    -8.6     95  0.5
  6750    7.7  45.9   255    6    3   4.8   2.6   12.5  54.6    -8.8     72  0.4
  6500    7.9  46.2   245    6    3   2.1   1.1   12.0  53.6    -9.4     58  0.3
  6250    8.1  46.6   235    6    3   1.6   0.9   11.4  52.5   -10.0     45  0.2
  6000    8.3  46.9   225    6    3   5.5   3.0   10.9  51.5   -10.5     33  0.2
  5750    8.5  47.3   210    6    3  -9.8  -5.4   10.3  50.5   -11.1     20  0.1
  5500    6.3  43.3   205    4    2 -45.9 -25.2    7.4  45.3   -14.1     78  0.4

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

           10/22/2017 at 0900 MDT          |       10/22/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +6.9        | CAPE...     0.0    LI...       +7.3
CINH...    -1.0    K Index...  +8.5        | CINH...    -0.7    K Index...  +8.5
                                           |
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  310  21 11   1.1   0.6 | -63.1 -81.6  300  20 10   1.5   0.8
 45000 -60.5 -76.9  315  30 16   1.2   0.6 | -60.8 -77.4  305  30 16   1.0   0.6
 40000 -58.7 -73.7  325  30 16   0.8   0.4 | -59.3 -74.7  325  35 18   2.5   1.4
 38000 -55.3 -67.5  325  34 17   5.7   3.1 | -55.6 -68.1  320  35 18   6.4   3.5
 36000 -51.9 -61.4  320  37 19   5.7   3.1 | -51.8 -61.2  320  34 18   6.4   3.5
 34000 -47.4 -53.3  320  37 19   8.5   4.7 | -47.2 -53.0  315  33 17   8.6   4.7
 32000 -42.3 -44.1  320  35 18   8.5   4.6 | -42.1 -43.8  310  32 16   8.6   4.7
 30000 -37.2 -35.0  320  33 17   8.7   4.8 | -36.4 -33.5  310  30 16   8.4   4.6
 29000 -34.6 -30.3  325  33 17   8.7   4.8 | -33.9 -29.0  315  30 15   8.4   4.6
 28000 -32.0 -25.6  325  32 16   8.7   4.8 | -31.4 -24.5  315  29 15   8.5   4.6
 27000 -29.4 -20.9  325  31 16   8.3   4.6 | -28.9 -20.0  315  28 14   8.1   4.4
 26000 -26.9 -16.4  325  30 15   8.3   4.5 | -26.5 -15.7  315  27 14   8.1   4.4
 25000 -24.5 -12.1  325  29 15   8.3   4.5 | -24.1 -11.4  315  26 14   8.1   4.4
 24000 -22.1  -7.8  325  27 14   7.7   4.2 | -21.7  -7.1  315  25 13   7.8   4.3
 23000 -19.8  -3.6  320  26 13   7.7   4.2 | -19.4  -2.9  315  24 13   7.8   4.3
 22000 -17.5   0.5  320  25 13   7.7   4.2 | -17.1   1.2  315  23 12   7.8   4.3
 21000 -15.4   4.3  320  23 12   6.1   3.4 | -14.9   5.2  315  22 11   7.3   4.0
 20000 -13.6   7.5  320  22 11   6.1   3.3 | -12.7   9.1  315  21 11   7.3   4.0
 19500 -12.3   9.9  315  20 10   6.1   3.4 | -11.7  10.9  315  20 10   7.3   4.0
 19000 -11.4  11.5  315  19 10   5.0   2.8 | -10.6  12.9  315  19 10   6.9   3.8
 18500 -10.7  12.7  315  18  9   4.6   2.5 |  -9.6  14.7  315  18  9   6.3   3.4
 18000 -10.1  13.8  315  17  9   4.5   2.5 |  -8.7  16.3  315  18  9   6.3   3.5
 17500  -9.3  15.3  315  16  8   5.1   2.8 |  -7.9  17.8  315  17  9   5.3   2.9
 17000  -8.6  16.5  315  16  8   5.0   2.8 |  -6.7  19.9  315  16  8   5.3   2.9
 16500  -7.8  18.0  320  15  8   5.4   3.0 |  -5.9  21.4  315  16  8   5.0   2.7
 16000  -7.0  19.4  320  14  7   5.5   3.0 |  -5.2  22.6  315  15  8   5.0   2.7
 15500  -6.2  20.8  320  13  7   5.8   3.2 |  -4.5  23.9  315  15  8   5.4   3.0
 15000  -5.3  22.5  320  12  6   6.3   3.4 |  -3.6  25.5  315  14  7   5.6   3.1
 14500  -4.4  24.1  320  12  6   6.2   3.4 |  -2.8  27.0  315  13  7   5.6   3.1
 14000  -3.4  25.9  320  11  6   6.1   3.3 |  -2.0  28.4  315  13  7   5.6   3.1
 13500  -2.5  27.5  315  11  6   6.1   3.3 |  -1.1  30.0  315  13  6   5.6   3.1
 13000  -1.7  28.9  315  10  5   5.9   3.2 |  -0.3  31.5  315  12  6   5.3   2.9
 12500  -0.8  30.6  315  10  5   5.9   3.2 |   0.5  32.9  310  12  6   5.3   2.9
 12000   0.1  32.2  310  10  5   6.2   3.4 |   1.1  34.0  305  12  6   4.1   2.3
 11500   1.0  33.8  310  10  5   6.2   3.4 |   1.8  35.2  305  11  6   4.2   2.3
 11000   2.0  35.6  310  10  5   6.0   3.3 |   2.5  36.5  300  11  5   5.9   3.2
 10500   2.9  37.2  305  10  5   6.2   3.4 |   3.4  38.1  295  10  5   5.7   3.1
 10250   3.3  37.9  305  10  5   5.2   2.9 |   3.8  38.8  295  10  5   5.8   3.2
 10000   3.6  38.5  305  10  5   5.0   2.7 |   4.2  39.6  295   9  5   6.9   3.8
  9750   4.1  39.4  305  11  6   5.8   3.2 |   4.8  40.6  295   9  5   7.7   4.2
  9500   4.5  40.1  305  11  6   5.5   3.0 |   5.4  41.7  295   9  5   7.2   4.0
  9250   4.8  40.6  300  11  6   3.8   2.1 |   5.8  42.4  295   9  5   5.6   3.1
  9000   5.1  41.2  300  11  6   3.1   1.7 |   6.2  43.2  295   9  5   5.7   3.1
  8750   5.4  41.7  300  11  6   4.3   2.4 |   6.7  44.1  290  10  5   7.1   3.9
  8500   5.7  42.3  295  11  6   4.1   2.3 |   7.2  45.0  290  10  5   6.2   3.4
  8250   6.0  42.8  295  11  5   3.3   1.8 |   7.6  45.7  290   9  5   4.8   2.6
  8000   6.2  43.2  290  10  5   3.1   1.7 |   8.0  46.4  285   9  5   4.9   2.7
  7750   6.5  43.7  285   9  5   3.2   1.7 |   8.4  47.1  285   8  4   5.2   2.9
  7500   6.7  44.1  285   9  4   4.3   2.4 |   8.8  47.8  280   7  4   7.6   4.2
  7250   7.1  44.8  280   7  4   5.1   2.8 |   9.5  49.1  280   6  3   9.5   5.2
  7000   7.5  45.5  275   6  3   5.3   2.9 |  10.2  50.4  275   5  3   8.8   4.8
  6750   7.9  46.2  270   4  2   3.5   1.9 |  10.8  51.4  275   4  2   8.6   4.7
  6500   8.1  46.6  260   4  2   2.9   1.6 |  11.5  52.7  275   4  2   9.3   5.1
  6250   8.4  47.1  245   4  2   4.6   2.5 |  12.2  54.0  275   4  2  10.3   5.7
  6000   8.7  47.7  230   3  2   2.9   1.6 |  13.0  55.4  275   4  2   9.3   5.1
  5750   8.7  47.7  210   3  2  -3.5  -1.9 |  13.7  56.7  275   3  2  13.2   7.3
  5500   8.1  46.6  200   3  2 -10.2  -5.6 |  15.0  59.0  275   3  2  21.8  12.0

           10/22/2017 at 1500 MDT          |       10/22/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +6.0        | CAPE...     0.0    LI...       +4.2
CINH...    -1.0    K Index... +10.1        | CINH...     0.0    K Index... +11.2
                                           |
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 -63.6 -82.5  330  37 19   1.4   0.8 | -63.7 -82.7  285  23 12   2.1   1.1
 45000 -61.4 -78.5  340  70 36   1.3   0.7 | -60.8 -77.4  330  62 32   0.4   0.2
 40000 -59.4 -74.9  345 104 54   3.3   1.8 | -60.2 -76.4  340  92 47   3.0   1.6
 38000 -55.6 -68.1  345  98 51   6.5   3.6 | -55.9 -68.6  340  86 44   7.3   4.0
 36000 -51.7 -61.1  345  92 47   6.5   3.6 | -51.6 -60.9  340  80 41   7.3   4.0
 34000 -47.0 -52.6  340  86 44   8.6   4.7 | -46.8 -52.2  340  78 40   8.2   4.5
 32000 -41.9 -43.4  340  79 41   8.6   4.7 | -41.3 -42.3  340  79 41   8.3   4.5
 30000 -36.1 -33.0  340  77 40   8.5   4.6 | -36.4 -33.5  340  80 41   8.2   4.5
 29000 -33.6 -28.5  340  77 40   8.5   4.6 | -33.9 -29.0  340  82 42   8.2   4.5
 28000 -31.1 -24.0  340  78 40   8.5   4.7 | -31.5 -24.7  340  83 43   8.2   4.5
 27000 -28.7 -19.7  340  77 40   8.0   4.4 | -29.1 -20.4  345  82 42   8.0   4.4
 26000 -26.3 -15.3  345  77 40   8.0   4.4 | -26.7 -16.1  345  80 41   8.0   4.4
 25000 -23.9 -11.0  345  76 39   8.0   4.4 | -24.3 -11.7  345  79 41   8.1   4.4
 24000 -21.6  -6.9  345  75 39   7.9   4.3 | -22.0  -7.6  345  78 40   7.6   4.2
 23000 -19.2  -2.6  345  74 38   7.9   4.3 | -19.8  -3.6  345  78 40   7.6   4.2
 22000 -16.9   1.6  345  72 37   7.9   4.4 | -17.5   0.5  345  78 40   7.6   4.2
 21000 -14.7   5.5  345  73 37   7.3   4.0 | -15.3   4.5  345  79 41   7.4   4.1
 20000 -12.5   9.5  350  75 39   7.3   4.0 | -13.1   8.4  350  81 42   7.4   4.1
 19500 -11.4  11.5  350  76 39   7.3   4.0 | -12.0  10.4  350  82 42   7.4   4.1
 19000 -10.3  13.5  350  77 40   7.0   3.8 | -10.9  12.4  350  83 43   7.5   4.1
 18500  -9.4  15.1  350  75 39   6.7   3.6 |  -9.8  14.4  350  83 43   7.6   4.2
 18000  -8.4  16.9  350  73 38   6.7   3.7 |  -8.7  16.3  350  82 42   7.6   4.2
 17500  -7.4  18.7  350  74 38   6.2   3.4 |  -7.1  19.2  350  81 42   7.1   3.9
 17000  -6.1  21.0  350  78 40   6.3   3.5 |  -6.0  21.2  350  81 42   7.1   3.9
 16500  -5.2  22.6  350  80 41   5.9   3.2 |  -5.0  23.0  350  80 41   7.4   4.0
 16000  -4.3  24.3  350  83 43   5.9   3.2 |  -3.9  25.0  350  80 41   7.4   4.0
 15500  -3.4  25.9  350  85 44   5.7   3.1 |  -2.8  27.0  350  79 41   6.9   3.8
 15000  -2.6  27.3  355  89 46   5.6   3.1 |  -1.8  28.8  350  79 41   6.8   3.7
 14500  -1.8  28.8  355  93 48   5.6   3.1 |  -0.8  30.6  350  78 40   6.7   3.7
 14000  -1.0  30.2  355  94 48   5.6   3.1 |   0.1  32.2  350  80 41   6.6   3.6
 13500  -0.1  31.8  355  95 49   5.7   3.1 |   1.1  34.0  350  81 42   6.6   3.6
 13000   0.7  33.3  355  96 50   6.0   3.3 |   2.1  35.8  350  82 42   6.9   3.8
 12500   1.6  34.9  355  98 50   6.0   3.3 |   3.1  37.6  350  82 42   6.8   3.7
 12000   2.5  36.5  355  95 49   6.3   3.4 |   4.1  39.4  350  78 40   6.3   3.5
 11500   3.4  38.1  355  90 46   6.3   3.4 |   5.1  41.2  350  73 37   6.3   3.4
 11000   4.4  39.9  350  83 43   6.9   3.8 |   5.9  42.6  345  66 34   4.7   2.6
 10500   5.4  41.7  350  75 39   6.9   3.8 |   6.6  43.9  345  58 30   5.1   2.8
 10250   5.9  42.6  350  71 37   7.1   3.9 |   7.0  44.6  340  55 28   5.8   3.2
 10000   6.5  43.7  350  67 35   6.8   3.7 |   7.4  45.3  340  51 26   5.5   3.0
  9750   7.0  44.6  350  62 32   6.5   3.6 |   7.8  46.0  340  44 23   5.0   2.7
  9500   7.4  45.3  350  57 30   6.4   3.5 |   8.2  46.8  335  38 20   5.4   3.0
  9250   7.9  46.2  345  52 27   4.4   2.4 |   8.6  47.5  330  33 17   5.5   3.0
  9000   8.2  46.8  345  45 23   5.8   3.2 |   9.0  48.2  330  29 15   7.0   3.9
  8750   8.7  47.7  345  38 19   8.0   4.4 |   9.6  49.3  325  24 13   8.2   4.5
  8500   9.3  48.7  340  31 16   7.7   4.2 |  10.2  50.4  320  20 10   8.1   4.5
  8250   9.9  49.8  340  27 14   8.3   4.6 |  10.8  51.4  315  16  8   8.6   4.7
  8000  10.5  50.9  340  24 12   8.6   4.7 |  11.5  52.7  310  14  7   8.5   4.7
  7750  11.2  52.2  340  23 12   8.8   4.8 |  12.1  53.8  300  12  6   8.2   4.5
  7500  11.8  53.2  345  23 12   9.6   5.3 |  12.7  54.9  290  10  5   8.8   4.8
  7250  12.6  54.7  345  25 13  10.2   5.6 |  13.4  56.1  280   8  4   9.5   5.2
  7000  13.3  55.9  350  27 14   9.9   5.5 |  14.1  57.4  270   7  4   9.2   5.0
  6750  14.1  57.4  350  29 15   9.4   5.1 |  14.7  58.5  250   7  3   8.0   4.4
  6500  14.8  58.6  350  30 15   9.6   5.3 |  15.3  59.5  245   6  3   8.2   4.5
  6250  15.5  59.9  350  31 16  10.4   5.7 |  16.0  60.8  240   5  3   8.8   4.9
  6000  16.3  61.3  350  33 17   9.2   5.1 |  16.6  61.9  240   5  2   9.2   5.0
  5750  17.0  62.6  350  34 17  12.7   6.9 |  17.2  63.0  235   4  2   3.8   2.1
  5500  18.3  64.9  355  35 18  21.2  11.7 |  17.0  62.6  205   6  3  -7.0  -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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