Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 190023
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1823 MDT Monday, September 18, 2017

This forecast is for Tuesday, September 19, 2017:

If the trigger temperature of 76.1 F/24.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 692 ft/min (3.5 m/s)
   Maximum height of thermals.................. 13963 ft MSL (8617 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 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................. 11624 ft MSL (6278 ft AGL)
Thermal soaring outlook for Wednesday 09/20.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Becoming poor
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 45879 ft MSL (40533 ft AGL)
Wave soaring outlook for Wednesday 09/20....... Poor

Remarks... Gusty west winds increasing in the mountains and foothills tonight.
           Speeds up to 50 mph possible.

Sunrise/Sunset.................... 06:44:50 / 19:01:23 MDT
Total possible sunshine........... 12 hr 16 min 33 sec (736 min 33 sec)
Altitude of sun at 12:53:06 MDT... 51.38 degrees

Upper air data from numerical model forecast valid on 09/19/2017 at 0600 MDT

Freezing level.................. 15771 ft MSL (10425 ft AGL)
Convective condensation level... 21922 ft MSL (16576 ft AGL)
Lifted condensation level....... 19554 ft MSL (14208 ft AGL)
Lifted index.................... +3.4
K index......................... -11.3

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  -62.3 -80.1   250   25   13  -1.0  -0.5      M     M       M      M    M
 45000  -63.0 -81.4   250   35   18   2.1   1.2      M     M       M      M    M
 40000  -59.9 -75.8   255   28   15   4.5   2.5      M     M       M      M    M
 38000  -55.2 -67.4   250   27   14   7.9   4.3      M     M       M      M    M
 36000  -50.5 -58.9   245   26   13   7.9   4.3      M     M       M      M    M
 34000  -45.6 -50.1   245   25   13   8.5   4.6      M     M       M      M    M
 32000  -40.5 -40.9   245   24   12   8.4   4.6      M     M       M      M    M
 30000  -34.7 -30.5   245   22   12   8.8   4.8   40.2 104.3     8.1      M    M
 29000  -32.1 -25.8   245   22   11   8.8   4.8   39.8 103.7     8.0      M    M
 28000  -29.4 -20.9   245   21   11   8.8   4.8   39.6 103.2     7.8      M    M
 27000  -26.8 -16.2   240   21   11   8.6   4.7   39.1 102.4     7.6      M    M
 26000  -24.3 -11.7   240   21   11   8.7   4.7   38.6 101.6     7.3      M    M
 25000  -21.7  -7.1   240   21   11   8.6   4.7   38.3 100.9     7.1      M    M
 24000  -19.2  -2.6   240   21   11   8.2   4.5   37.8 100.1     6.8      M    M
 23000  -16.7   1.9   245   20   10   8.2   4.5   37.2  99.0     6.3      M    M
 22000  -14.3   6.3   245   19   10   8.2   4.5   36.7  98.0     6.0      M    M
 21000  -12.0  10.4   245   19   10   7.5   4.1   36.0  96.8     5.4      M    M
 20000   -9.7  14.5   245   19   10   7.5   4.1   35.2  95.3     4.8      M    M
 19500   -8.6  16.5   245   18    9   7.5   4.1   34.8  94.7     4.5      M    M
 19000   -7.5  18.5   245   18    9   7.5   4.1   34.5  94.0     4.2      M    M
 18500   -6.4  20.5   245   18    9   7.3   4.0   34.1  93.3     3.9      M    M
 18000   -5.3  22.5   245   18    9   7.4   4.0   33.7  92.6     3.5      M    M
 17500   -3.6  25.5   245   18    9   7.5   4.1   33.1  91.5     3.0      M    M
 17000   -2.5  27.5   245   18    9   7.5   4.1   32.7  90.8     2.7      M    M
 16500   -1.4  29.5   245   17    9   7.2   3.9   32.3  90.1     2.4      M    M
 16000   -0.3  31.5   245   16    8   7.1   3.9   31.8  89.3     2.0      M    M
 15500    0.8  33.4   240   16    8   6.9   3.8   31.4  88.5     1.6      M    M
 15000    1.7  35.1   240   15    8   6.2   3.4   30.8  87.5     1.1      M    M
 14500    2.6  36.7   235   15    8   6.4   3.5   30.2  86.4     0.6      M    M
 14000    3.5  38.3   235   14    7   4.7   2.6   29.6  85.2    -0.0    691  3.5
 13500    4.2  39.6   235   14    7   4.9   2.7   28.8  83.8    -0.8    655  3.3
 13000    4.9  40.8   235   13    7   5.8   3.2   28.0  82.5    -1.5    617  3.1
 12500    5.8  42.4   235   11    6   6.0   3.3   27.4  81.4    -2.1    576  2.9
 12000    6.7  44.1   230   10    5   6.7   3.7   26.8  80.3    -2.7    535  2.7
 11500    7.7  45.9   230    8    4   7.0   3.8   26.4  79.5    -3.1    490  2.5
 11000    8.7  47.7   225    6    3   6.9   3.8   26.0  78.8    -3.6    445  2.3
 10500    9.7  49.5   230    4    2   6.2   3.4   25.5  77.9    -4.1    400  2.0
 10250   10.3  50.5   230    4    2  10.3   5.7   25.3  77.6    -4.3    377  1.9
 10000   11.1  52.0   230    3    2  10.3   5.6   25.5  77.9    -4.1    343  1.7
  9750   11.7  53.1   235    3    2   6.4   3.5   25.3  77.5    -4.4    320  1.6
  9500   12.2  54.0   240    3    2   7.3   4.0   25.1  77.1    -4.6    297  1.5
  9250   12.7  54.9   250    3    2   7.5   4.1   24.9  76.8    -4.8    274  1.4
  9000   13.3  55.9   250    3    2   7.5   4.1   24.7  76.5    -5.0    250  1.3
  8750   13.8  56.8   250    3    1   7.1   3.9   24.5  76.1    -5.2    227  1.2
  8500   14.3  57.7   250    3    1   7.0   3.9   24.3  75.8    -5.4    204  1.0
  8250   14.8  58.6   245    2    1   7.7   4.2   24.1  75.4    -5.7    181  0.9
  8000   15.4  59.7   245    2    1   7.5   4.1   24.0  75.2    -5.8    157  0.8
  7750   15.9  60.6   240    2    1   6.1   3.3   23.7  74.7    -6.1    135  0.7
  7500   16.3  61.3   230    2    1   5.9   3.2   23.4  74.2    -6.4    115  0.6
  7250   16.7  62.1   220    3    1   6.0   3.3   23.2  73.7    -6.7     94  0.5
  7000   17.2  63.0   220    3    2   5.6   3.1   22.9  73.2    -7.0     74  0.4
  6750   17.5  63.5   215    3    2   3.1   1.7   22.5  72.5    -7.4     56  0.3
  6500   17.7  63.9   215    4    2   2.9   1.6   21.9  71.4    -8.0     44  0.2
  6250   17.8  64.0   210    5    2  -2.7  -1.5   21.3  70.4    -8.7     34  0.2
  6000   17.2  63.0   210    5    3  -8.5  -4.7   20.0  68.1   -10.0     43  0.2
  5750   16.6  61.9   210    6    3  -6.4  -3.5   18.8  65.8   -11.3     53  0.3
  5500   15.9  60.6   205    6    3 -14.2  -7.8   17.4  63.2   -12.8     67  0.3

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

           09/19/2017 at 0900 MDT          |       09/19/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +6.5        | CAPE...     0.0    LI...       +6.9
CINH...    -0.0    K Index...  -8.6        | CINH...    -0.1    K Index...  +1.4
                                           |
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 -62.6 -80.7  255  27 14  -2.4  -1.3 | -63.1 -81.6  250  28 14  -3.7  -2.0
 45000 -64.8 -84.6  260  36 19   3.6   2.0 | -66.9 -88.4  255  37 19   4.9   2.7
 40000 -59.4 -74.9  260  31 16   5.6   3.1 | -59.0 -74.2  255  32 16   6.8   3.7
 38000 -54.7 -66.5  255  30 15   7.9   4.4 | -54.1 -65.4  255  31 16   8.2   4.5
 36000 -49.9 -57.8  250  28 15   7.9   4.4 | -49.2 -56.6  255  30 15   8.2   4.5
 34000 -45.0 -49.0  250  27 14   8.4   4.6 | -44.2 -47.6  255  29 15   8.5   4.6
 32000 -40.0 -40.0  250  26 14   8.4   4.6 | -39.2 -38.6  255  28 14   8.4   4.6
 30000 -34.5 -30.1  250  25 13   8.1   4.4 | -33.6 -28.5  250  27 14   8.3   4.5
 29000 -32.1 -25.8  250  25 13   8.1   4.4 | -31.1 -24.0  250  27 14   8.3   4.6
 28000 -29.7 -21.5  245  24 12   8.1   4.4 | -28.6 -19.5  250  27 14   8.3   4.6
 27000 -27.2 -17.0  245  23 12   8.4   4.6 | -26.2 -15.2  250  27 14   8.1   4.4
 26000 -24.7 -12.5  245  22 11   8.4   4.6 | -23.8 -10.8  250  26 13   8.1   4.5
 25000 -22.2  -8.0  240  21 11   8.4   4.6 | -21.3  -6.3  250  26 13   8.1   4.5
 24000 -19.7  -3.5  240  21 11   8.3   4.5 | -18.9  -2.0  250  25 13   8.0   4.4
 23000 -17.2   1.0  240  20 10   8.3   4.5 | -16.6   2.1  245  25 13   8.0   4.4
 22000 -14.7   5.5  240  20 10   8.3   4.5 | -14.2   6.4  245  25 13   8.0   4.4
 21000 -12.3   9.9  240  20 10   7.9   4.4 | -11.9  10.6  245  24 13   7.6   4.1
 20000 -10.0  14.0  240  19 10   7.9   4.3 |  -9.6  14.7  245  24 12   7.5   4.1
 19500  -8.8  16.2  240  19 10   7.9   4.3 |  -8.5  16.7  245  24 12   7.6   4.1
 19000  -7.6  18.3  240  19 10   7.9   4.3 |  -7.4  18.7  245  24 12   7.5   4.1
 18500  -6.4  20.5  240  19 10   7.5   4.1 |  -6.3  20.7  245  24 12   7.1   3.9
 18000  -5.3  22.5  240  19 10   7.5   4.1 |  -5.3  22.5  245  23 12   7.1   3.9
 17500  -3.6  25.5  240  19 10   7.5   4.1 |  -4.2  24.4  240  23 12   6.9   3.8
 17000  -2.5  27.5  240  19 10   7.6   4.1 |  -2.7  27.1  245  23 12   6.8   3.7
 16500  -1.4  29.5  240  18  9   7.3   4.0 |  -1.7  28.9  245  23 12   6.5   3.6
 16000  -0.3  31.5  240  18  9   7.2   4.0 |  -0.8  30.6  245  22 11   6.4   3.5
 15500   0.8  33.4  240  18  9   7.0   3.8 |   0.1  32.2  245  22 11   6.4   3.5
 15000   1.8  35.2  245  18  9   6.2   3.4 |   1.1  34.0  245  21 11   6.5   3.5
 14500   2.7  36.9  245  17  9   6.3   3.5 |   2.1  35.8  245  20 10   6.5   3.6
 14000   3.6  38.5  245  17  9   5.8   3.2 |   3.0  37.4  245  19 10   6.3   3.5
 13500   4.5  40.1  245  16  8   5.9   3.2 |   4.0  39.2  250  18  9   6.3   3.5
 13000   5.3  41.5  250  16  8   5.7   3.1 |   4.9  40.8  250  18  9   6.7   3.7
 12500   6.1  43.0  250  14  7   5.6   3.1 |   5.9  42.6  250  16  8   6.7   3.7
 12000   7.0  44.6  250  13  7   6.2   3.4 |   6.9  44.4  245  15  8   6.3   3.5
 11500   7.9  46.2  250  13  6   6.5   3.6 |   7.8  46.0  250  14  7   6.1   3.3
 11000   8.9  48.0  255  12  6   6.2   3.4 |   8.7  47.7  250  13  7   6.6   3.6
 10500   9.8  49.6  250  10  5   5.6   3.1 |   9.7  49.5  245  10  5   7.1   3.9
 10250  10.2  50.4  250  10  5   8.6   4.7 |  10.3  50.5  245   9  5   8.6   4.7
 10000  11.0  51.8  255  10  5   9.3   5.1 |  10.9  51.6  245   9  5   9.3   5.1
  9750  11.5  52.7  255   9  5   7.0   3.8 |  11.6  52.9  240   8  4   8.7   4.7
  9500  12.1  53.8  255   9  5   7.6   4.2 |  12.3  54.1  240   7  4   9.2   5.0
  9250  12.6  54.7  255   8  4   7.4   4.1 |  12.9  55.2  235   6  3   7.7   4.2
  9000  13.2  55.8  255   9  5   7.2   3.9 |  13.4  56.1  235   6  3   7.8   4.3
  8750  13.7  56.7  255   9  4   7.0   3.8 |  14.1  57.4  230   6  3   9.2   5.1
  8500  14.2  57.6  255   8  4   7.1   3.9 |  14.7  58.5  230   5  3   8.9   4.9
  8250  14.7  58.5  255   8  4   6.7   3.7 |  15.4  59.7  225   5  3   8.8   4.8
  8000  15.2  59.4  255   7  4   6.0   3.3 |  16.1  61.0  220   4  2   9.1   5.0
  7750  15.6  60.1  250   6  3   6.1   3.4 |  16.8  62.2  215   4  2   9.7   5.3
  7500  16.0  60.8  245   6  3   6.3   3.5 |  17.5  63.5  215   4  2   9.7   5.3
  7250  16.5  61.7  240   5  3   6.2   3.4 |  18.2  64.8  215   4  2   9.2   5.0
  7000  16.9  62.4  235   5  2   5.7   3.2 |  18.9  66.0  210   4  2   8.7   4.8
  6750  17.3  63.1  230   4  2   4.9   2.7 |  19.6  67.3  205   3  2  10.2   5.6
  6500  17.7  63.9  220   4  2   4.8   2.6 |  20.4  68.7  205   3  2  11.2   6.1
  6250  18.0  64.4  215   5  2   3.6   2.0 |  21.2  70.2  205   3  2  10.5   5.8
  6000  18.2  64.8  205   5  2   2.7   1.5 |  22.0  71.6  195   3  2  10.5   5.8
  5750  18.3  64.9  200   5  2   1.4   0.8 |  22.7  72.9  190   3  1   9.2   5.1
  5500  18.3  64.9  200   4  2  -0.9  -0.5 |  23.5  74.3  195   3  1  12.8   7.0

           09/19/2017 at 1500 MDT          |       09/19/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +4.7        | CAPE...     0.0    LI...       +4.4
CINH...    -0.1    K Index...  +5.9        | CINH...     0.0    K Index... +12.6
                                           |
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 -63.1 -81.6  250  28 14  -3.9  -2.1 | -62.9 -81.2  255  28 14  -4.1  -2.3
 45000 -67.1 -88.8  255  36 19   5.4   3.0 | -67.0 -88.6  255  34 17   5.7   3.1
 40000 -58.5 -73.3  255  35 18   7.0   3.8 | -58.0 -72.4  265  37 19   7.1   3.9
 38000 -53.7 -64.7  255  35 18   8.0   4.4 | -53.4 -64.1  260  36 18   7.8   4.3
 36000 -48.9 -56.0  255  34 18   8.0   4.4 | -48.7 -55.7  255  35 18   7.8   4.3
 34000 -43.8 -46.8  255  33 17   8.7   4.8 | -43.5 -46.3  250  33 17   9.0   4.9
 32000 -38.6 -37.5  250  32 17   8.7   4.8 | -38.1 -36.6  250  31 16   9.0   4.9
 30000 -32.9 -27.2  250  32 17   8.5   4.7 | -32.8 -27.0  250  30 16   8.8   4.8
 29000 -30.3 -22.5  250  32 17   8.5   4.7 | -29.5 -21.1  250  31 16   8.8   4.8
 28000 -27.8 -18.0  255  33 17   8.6   4.7 | -26.9 -16.4  255  32 17   8.9   4.9
 27000 -25.4 -13.7  255  33 17   7.9   4.3 | -24.5 -12.1  255  33 17   7.9   4.4
 26000 -23.0  -9.4  255  34 17   7.9   4.3 | -22.1  -7.8  255  34 17   7.9   4.4
 25000 -20.7  -5.3  255  34 18   7.9   4.3 | -19.7  -3.5  260  34 18   7.9   4.3
 24000 -18.4  -1.1  255  34 18   7.4   4.0 | -17.5   0.5  260  35 18   6.5   3.6
 23000 -16.2   2.8  255  33 17   7.4   4.0 | -15.6   3.9  255  34 18   6.5   3.6
 22000 -14.0   6.8  250  32 17   7.3   4.0 | -13.7   7.3  255  34 17   6.5   3.6
 21000 -12.0  10.4  250  31 16   6.5   3.6 | -11.9  10.6  255  33 17   5.6   3.1
 20000 -10.1  13.8  250  30 15   6.5   3.6 | -10.2  13.6  255  31 16   5.6   3.1
 19500  -9.1  15.6  250  29 15   6.5   3.6 |  -9.4  15.1  255  31 16   5.6   3.1
 19000  -8.2  17.2  250  28 14   6.5   3.6 |  -8.6  16.5  255  30 16   5.7   3.2
 18500  -7.2  19.0  250  27 14   6.2   3.4 |  -7.9  17.8  255  29 15   4.2   2.3
 18000  -6.3  20.7  250  26 13   6.3   3.4 |  -7.3  18.9  255  28 14   4.4   2.4
 17500  -5.4  22.3  245  25 13   6.3   3.5 |  -6.6  20.1  255  26 13   4.3   2.4
 17000  -4.5  23.9  245  24 12   6.3   3.5 |  -6.1  21.0  255  24 12   4.2   2.3
 16500  -3.5  25.7  245  23 12   6.3   3.5 |  -5.5  22.1  255  21 11   4.1   2.2
 16000  -2.1  28.2  245  21 11   6.8   3.7 |  -4.1  24.6  250  18  9   6.8   3.7
 15500  -1.1  30.0  250  20 10   6.8   3.7 |  -3.1  26.4  250  16  8   7.1   3.9
 15000  -0.0  32.0  250  19 10   6.8   3.7 |  -1.9  28.6  250  15  8   9.0   5.0
 14500   1.0  33.8  245  18  9   6.6   3.6 |  -0.6  30.9  250  14  7   8.8   4.9
 14000   2.1  35.8  245  16  8   8.4   4.6 |   0.8  33.4  250  13  7   9.7   5.3
 13500   3.3  37.9  245  15  8   8.2   4.5 |   2.2  36.0  250  12  6   9.7   5.3
 13000   4.6  40.3  245  14  7   9.1   5.0 |   3.7  38.7  245  12  6   9.7   5.3
 12500   5.9  42.6  240  13  6   9.3   5.1 |   5.1  41.2  250  11  6   9.7   5.3
 12000   7.3  45.1  240  12  6   9.3   5.1 |   6.5  43.7  250  11  6   9.8   5.4
 11500   8.7  47.7  240  11  5   9.3   5.1 |   8.0  46.4  250  10  5   9.8   5.4
 11000  10.1  50.2  240  10  5   8.8   4.8 |   9.5  49.1  250  10  5   9.1   5.0
 10500  11.3  52.3  240   9  5   8.7   4.8 |  10.7  51.3  250  10  5   8.8   4.8
 10250  12.1  53.8  240   9  4  11.4   6.3 |  11.5  52.7  250   9  5  11.9   6.5
 10000  13.0  55.4  240   8  4  10.9   6.0 |  12.4  54.3  250   9  5  11.3   6.2
  9750  13.7  56.7  240   8  4   9.2   5.0 |  13.1  55.6  250   9  5   9.1   5.0
  9500  14.4  57.9  240   8  4   9.3   5.1 |  13.8  56.8  250   9  4   9.4   5.2
  9250  15.1  59.2  240   8  4  10.4   5.7 |  14.5  58.1  255   8  4  10.1   5.5
  9000  15.9  60.6  240   8  4  10.6   5.8 |  15.3  59.5  255   8  4  10.3   5.6
  8750  16.6  61.9  240   8  4   9.7   5.3 |  16.0  60.8  255   8  4   9.8   5.4
  8500  17.4  63.3  240   7  4   9.7   5.3 |  16.8  62.2  255   8  4   9.6   5.2
  8250  18.1  64.6  240   7  4  10.9   6.0 |  17.5  63.5  255   8  4  10.9   6.0
  8000  19.0  66.2  240   7  4  10.6   5.8 |  18.4  65.1  255   8  4  10.7   5.9
  7750  19.7  67.5  240   7  4   9.2   5.0 |  19.1  66.4  260   7  4   9.2   5.0
  7500  20.4  68.7  240   7  4   9.4   5.1 |  19.8  67.6  260   7  4   9.5   5.2
  7250  21.1  70.0  240   7  4   9.9   5.5 |  20.5  68.9  260   7  4   9.9   5.4
  7000  21.9  71.4  240   7  3  11.1   6.1 |  21.3  70.3  260   7  4  10.4   5.7
  6750  22.7  72.9  240   7  3  10.1   5.5 |  22.0  71.6  260   7  4   9.4   5.2
  6500  23.4  74.1  240   6  3   9.1   5.0 |  22.7  72.9  260   7  3   8.5   4.6
  6250  24.1  75.4  240   6  3   9.8   5.4 |  23.3  73.9  260   6  3   9.7   5.3
  6000  24.9  76.8  240   6  3  11.0   6.1 |  24.1  75.4  265   6  3  11.3   6.2
  5750  25.7  78.3  240   6  3   9.7   5.3 |  24.9  76.8  265   6  3  10.2   5.6
  5500  26.4  79.5  240   6  3  14.0   7.7 |  25.6  78.1  265   5  3   8.6   4.7
________________________________________________________________________________

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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