Soaring Guidance
Issued by NWS Denver/Boulder, CO

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149
UXUS97 KBOU 220054
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1854 MDT Thursday, September 21, 2017

This forecast is for Friday, September 22, 2017:

If the trigger temperature of 73.2 F/22.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 812 ft/min (4.1 m/s)
   Maximum height of thermals.................. 15331 ft MSL (9996 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1015 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................. 13337 ft MSL (8001 ft AGL)
Thermal soaring outlook for Saturday 09/23..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 45961 ft MSL (40626 ft AGL)
Wave soaring outlook for Saturday 09/23........ Poor

Remarks... Strong south/southwest flow aloft through Saturday

Sunrise/Sunset.................... 06:47:39 / 18:56:26 MDT
Total possible sunshine........... 12 hr 8 min 47 sec (728 min 47 sec)
Altitude of sun at 12:52:03 MDT... 50.21 degrees

Upper air data from numerical model forecast valid on 09/22/2017 at 0600 MDT

Freezing level.................. 14810 ft MSL (9475 ft AGL)
Convective condensation level... 19445 ft MSL (14110 ft AGL)
Lifted condensation level....... 17686 ft MSL (12351 ft AGL)
Lifted index.................... +1.0
K index......................... +8.6

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  -65.7 -86.3   225   28   14   3.1   1.7      M     M       M      M    M
 45000  -60.6 -77.1   230   41   21   4.5   2.4      M     M       M      M    M
 40000  -53.9 -65.0   230   43   22   5.1   2.8      M     M       M      M    M
 38000  -50.5 -58.9   230   41   21   5.6   3.1      M     M       M      M    M
 36000  -47.1 -52.8   225   38   20   5.6   3.1      M     M       M      M    M
 34000  -42.3 -44.1   225   36   19   8.0   4.4      M     M       M      M    M
 32000  -37.5 -35.5   225   35   18   8.0   4.4      M     M       M      M    M
 30000  -32.7 -26.9   215   32   16   8.0   4.4   43.0 109.5    10.3      M    M
 29000  -30.3 -22.5   210   30   16   8.0   4.4   42.4 108.3     9.9      M    M
 28000  -27.9 -18.2   205   29   15   8.1   4.4   41.8 107.3     9.6      M    M
 27000  -25.8 -14.4   205   29   15   6.7   3.7   40.8 105.4     8.9      M    M
 26000  -23.8 -10.8   205   29   15   6.8   3.7   39.6 103.2     8.0      M    M
 25000  -21.8  -7.2   200   29   15   6.9   3.8   38.5 101.3     7.2      M    M
 24000  -19.6  -3.3   200   28   15   8.3   4.5   37.7  99.8     6.6      M    M
 23000  -17.1   1.2   205   28   14   8.2   4.5   37.1  98.7     6.2      M    M
 22000  -14.6   5.7   205   27   14   8.2   4.5   36.6  97.9     5.8      M    M
 21000  -12.2  10.0   205   26   13   7.9   4.3   36.0  96.8     5.4      M    M
 20000   -9.8  14.4   205   25   13   7.9   4.3   35.3  95.6     4.9      M    M
 19500   -8.6  16.5   210   24   13   7.9   4.3   35.0  95.0     4.7      M    M
 19000   -6.8  19.8   210   24   12   7.1   3.9   34.6  94.3     4.4      M    M
 18500   -5.9  21.4   210   23   12   6.5   3.6   34.0  93.2     3.9      M    M
 18000   -4.9  23.2   210   23   12   6.5   3.6   33.4  92.2     3.4      M    M
 17500   -4.0  24.8   215   22   12   5.8   3.2   32.8  91.1     2.9      M    M
 17000   -3.1  26.4   215   22   11   5.9   3.2   32.2  89.9     2.3      M    M
 16500   -2.3  27.9   215   22   11   5.3   2.9   31.5  88.7     1.7      M    M
 16000   -1.6  29.1   215   22   11   4.9   2.7   30.7  87.2     0.9      M    M
 15500   -0.9  30.4   220   22   11   5.0   2.7   29.9  85.8     0.2      M    M
 15000   -0.2  31.6   220   21   11   5.1   2.8   29.1  84.4    -0.6    783  4.0
 14500    0.5  32.9   220   21   11   5.2   2.8   28.3  83.0    -1.4    747  3.8
 14000    1.3  34.3   225   21   11   5.5   3.0   27.6  81.7    -2.1    710  3.6
 13500    2.0  35.6   225   20   10   5.5   3.0   26.9  80.4    -2.8    673  3.4
 13000    2.8  37.0   230   20   10   6.4   3.5   26.3  79.3    -3.5    634  3.2
 12500    3.7  38.7   230   19   10   6.5   3.6   25.7  78.3    -4.1    591  3.0
 12000    4.7  40.5   230   18    9   7.3   4.0   25.2  77.4    -4.6    548  2.8
 11500    5.8  42.4   230   16    8   7.6   4.2   24.9  76.8    -5.0    501  2.5
 11000    6.9  44.4   235   15    8   7.7   4.2   24.6  76.2    -5.4    453  2.3
 10500    8.0  46.4   235   14    7   7.7   4.2   24.3  75.7    -5.7    404  2.1
 10250    8.6  47.5   230   13    7   8.3   4.6   24.1  75.4    -5.9    379  1.9
 10000    9.3  48.7   230   13    7   8.6   4.7   24.0  75.3    -6.0    352  1.8
  9750    9.9  49.8   230   12    6   8.3   4.6   23.9  75.1    -6.1    326  1.7
  9500   10.5  50.9   235   12    6   8.2   4.5   23.8  74.9    -6.2    300  1.5
  9250   11.1  52.0   235   12    6   8.9   4.9   23.7  74.7    -6.3    274  1.4
  9000   11.8  53.2   235   11    6   8.7   4.8   23.7  74.6    -6.4    245  1.2
  8750   12.5  54.5   230   11    6   8.1   4.4   23.5  74.4    -6.5    219  1.1
  8500   13.1  55.6   230   10    5   8.0   4.4   23.4  74.1    -6.6    193  1.0
  8250   13.7  56.7   230   10    5   8.9   4.9   23.3  73.9    -6.8    167  0.8
  8000   14.4  57.9   230    9    5   9.2   5.1   23.3  73.9    -6.8    138  0.7
  7750   15.1  59.2   225    9    5   8.1   4.5   23.2  73.7    -6.9    111  0.6
  7500   15.7  60.3   225    9    5   7.4   4.1   23.0  73.5    -7.0     86  0.4
  7250   16.3  61.3   220    9    5   9.3   5.1   22.9  73.2    -7.2     61  0.3
  7000   17.0  62.6   215    9    5  11.1   6.1   23.0  73.3    -7.1     30  0.2
  6750   17.8  64.0   210    9    5   8.3   4.5   23.0  73.4    -7.2      1  0.0
  6500   18.3  64.9   210    9    5   6.9   3.8   22.8  73.0    -7.4      M    M
  6250   18.6  65.5   205    9    5  -1.9  -1.0   22.4  72.3    -7.8      M    M
  6000   18.1  64.6   205    9    5  -8.4  -4.6   21.1  69.9    -9.1      M    M
  5750   17.5  63.5   200    9    5  -9.9  -5.4   19.7  67.5   -10.5      M    M
  5500   16.3  61.3   200    8    4 -22.7 -12.5   17.8  64.1   -12.4      7  0.0

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

           09/22/2017 at 0900 MDT          |       09/22/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.0        | CAPE...     0.0    LI...       +2.0
CINH...     0.0    K Index...  +9.4        | CINH...     0.0    K Index... +16.8
                                           |
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 -64.7 -84.5  215  27 14   2.9   1.6 | -64.1 -83.4  215  31 16   2.6   1.4
 45000 -59.9 -75.8  225  43 22   4.3   2.3 | -59.9 -75.8  225  45 23   3.5   1.9
 40000 -53.5 -64.3  230  47 24   5.0   2.7 | -54.6 -66.3  225  50 26   4.5   2.5
 38000 -50.1 -58.2  225  46 24   5.7   3.1 | -51.0 -59.8  225  50 26   6.0   3.3
 36000 -46.7 -52.1  225  46 23   5.6   3.1 | -47.3 -53.1  220  50 26   6.0   3.3
 34000 -42.2 -44.0  225  43 22   7.4   4.0 | -42.6 -44.7  220  47 24   7.6   4.2
 32000 -37.8 -36.0  220  40 21   7.4   4.0 | -38.0 -36.4  220  43 22   7.6   4.2
 30000 -33.1 -27.6  215  36 18   8.0   4.4 | -33.2 -27.8  215  39 20   8.2   4.5
 29000 -30.7 -23.3  215  34 17   8.0   4.4 | -30.7 -23.3  210  37 19   8.2   4.5
 28000 -28.3 -18.9  210  32 16   8.1   4.4 | -28.3 -18.9  210  35 18   8.3   4.5
 27000 -26.3 -15.3  205  31 16   6.3   3.4 | -26.1 -15.0  205  33 17   6.6   3.6
 26000 -24.4 -11.9  200  30 15   6.3   3.4 | -24.2 -11.6  205  32 16   6.6   3.6
 25000 -22.6  -8.7  195  29 15   6.4   3.5 | -22.2  -8.0  205  31 16   6.6   3.6
 24000 -20.5  -4.9  195  29 15   8.7   4.8 | -20.2  -4.4  200  30 15   7.3   4.0
 23000 -17.9  -0.2  195  28 15   8.6   4.7 | -18.0  -0.4  200  30 15   7.4   4.1
 22000 -15.3   4.5  200  28 14   8.6   4.7 | -15.8   3.6  200  29 15   7.6   4.2
 21000 -12.9   8.8  200  28 14   7.6   4.2 | -13.6   7.5  205  29 15   7.5   4.1
 20000 -10.5  13.1  205  28 14   7.6   4.2 | -11.3  11.7  205  30 15   7.5   4.1
 19500  -9.4  15.1  205  28 14   7.7   4.2 | -10.2  13.6  210  30 15   7.5   4.1
 19000  -8.2  17.2  210  28 14   7.8   4.3 |  -9.0  15.8  210  30 16   7.6   4.2
 18500  -7.2  19.0  210  27 14   5.1   2.8 |  -8.0  17.6  215  30 16   6.4   3.5
 18000  -6.0  21.2  215  26 13   5.5   3.0 |  -6.5  20.3  215  31 16   6.7   3.7
 17500  -5.2  22.6  215  26 13   5.2   2.9 |  -5.6  21.9  215  31 16   5.3   2.9
 17000  -4.5  23.9  215  25 13   5.3   2.9 |  -4.8  23.4  220  30 16   5.4   3.0
 16500  -3.7  25.3  215  25 13   4.9   2.7 |  -4.0  24.8  220  30 16   5.6   3.1
 16000  -3.0  26.6  220  24 12   4.8   2.6 |  -3.2  26.2  225  30 15   5.8   3.2
 15500  -2.4  27.7  220  23 12   4.9   2.7 |  -2.4  27.7  225  29 15   5.8   3.2
 15000  -1.6  29.1  225  22 11   5.4   3.0 |  -1.6  29.1  230  28 14   5.6   3.1
 14500  -0.9  30.4  225  21 11   5.3   2.9 |  -0.8  30.6  230  27 14   5.7   3.2
 14000   0.0  32.0  225  21 11   6.8   3.7 |  -0.1  31.8  230  25 13   5.5   3.0
 13500   1.0  33.8  230  20 10   6.7   3.7 |   0.7  33.3  230  23 12   5.5   3.0
 13000   1.9  35.4  230  19 10   6.7   3.7 |   1.5  34.7  230  20 10   6.5   3.5
 12500   2.9  37.2  230  18  9   6.7   3.7 |   2.4  36.3  225  18  9   6.6   3.6
 12000   3.8  38.8  230  17  9   7.5   4.1 |   3.4  38.1  220  15  8   7.5   4.1
 11500   5.0  41.0  230  16  8   7.8   4.3 |   4.5  40.1  215  14  7   7.7   4.2
 11000   6.1  43.0  230  14  7   7.3   4.0 |   5.6  42.1  210  12  6   8.0   4.4
 10500   7.1  44.8  230  13  7   6.9   3.8 |   6.9  44.4  205  11  6   7.5   4.1
 10250   7.6  45.7  230  12  6   8.2   4.5 |   7.5  45.5  200  11  6  10.9   6.0
 10000   8.2  46.8  230  12  6   9.1   5.0 |   8.4  47.1  195  11  5  11.7   6.4
  9750   8.8  47.8  230  11  6   8.5   4.6 |   9.1  48.4  195  10  5   8.9   4.9
  9500   9.5  49.1  225  10  5   8.7   4.8 |   9.8  49.6  195  10  5   9.4   5.2
  9250  10.1  50.2  225  10  5   8.4   4.6 |  10.5  50.9  195  10  5  10.0   5.5
  9000  10.7  51.3  225  10  5   8.3   4.6 |  11.3  52.3  195  10  5  10.0   5.5
  8750  11.3  52.3  220   9  5   8.7   4.8 |  12.0  53.6  195  10  5   9.3   5.1
  8500  11.9  53.4  215   9  5   8.2   4.5 |  12.7  54.9  195  10  5   9.1   5.0
  8250  12.6  54.7  210   9  5  10.0   5.5 |  13.4  56.1  195  10  5  10.7   5.9
  8000  13.4  56.1  205   9  5  10.6   5.8 |  14.3  57.7  195  10  5  11.3   6.2
  7750  14.1  57.4  205   9  5   8.2   4.5 |  15.0  59.0  195   9  5   9.4   5.1
  7500  14.7  58.5  200   9  5   7.5   4.1 |  15.7  60.3  195   9  5   8.9   4.9
  7250  15.2  59.4  200   9  5   8.4   4.6 |  16.4  61.5  195   9  5  10.3   5.7
  7000  15.9  60.6  195   9  5   8.7   4.8 |  17.2  63.0  195   9  5  11.4   6.3
  6750  16.5  61.7  195  10  5   6.5   3.6 |  18.0  64.4  195   9  5   9.4   5.2
  6500  16.9  62.4  190  10  5   4.6   2.5 |  18.7  65.7  195   9  5   9.0   5.0
  6250  17.2  63.0  190  10  5   1.7   0.9 |  19.4  66.9  195   9  4  11.2   6.2
  6000  17.2  63.0  190   9  4  -0.2  -0.1 |  20.4  68.7  195   8  4  13.1   7.2
  5750  17.3  63.1  190   7  4   1.2   0.7 |  21.2  70.2  195   8  4   9.3   5.1
  5500  17.6  63.7  190   5  3   8.2   4.5 |  21.9  71.4  195   8  4  12.4   6.8

           09/22/2017 at 1500 MDT          |       09/22/2017 at 1800 MDT
                                           |
CAPE...  +136.2    LI...       -0.8        | CAPE...  +115.9    LI...       -1.3
CINH...    -1.5    K Index... +28.3        | CINH...    -9.3    K Index... +27.9
                                           |
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 -64.2 -83.6  215  38 19   3.9   2.1 | -64.2 -83.6  215  40 21   4.2   2.3
 45000 -58.8 -73.8  225  45 23   2.5   1.4 | -58.5 -73.3  225  46 24   1.8   1.0
 40000 -55.0 -67.0  220  46 24   4.3   2.4 | -55.8 -68.4  220  49 25   3.5   1.9
 38000 -51.0 -59.8  220  48 25   6.7   3.7 | -51.7 -61.1  220  50 26   7.1   3.9
 36000 -47.0 -52.6  220  50 26   6.7   3.7 | -47.4 -53.3  220  51 26   7.1   3.9
 34000 -42.2 -44.0  215  50 25   7.3   4.0 | -42.3 -44.1  220  51 26   7.8   4.3
 32000 -37.8 -36.0  215  47 24   7.3   4.0 | -37.6 -35.7  220  50 26   7.9   4.3
 30000 -33.3 -27.9  215  43 22   7.6   4.2 | -33.5 -28.3  220  48 25   6.3   3.5
 29000 -31.1 -24.0  215  41 21   7.6   4.2 | -31.6 -24.9  220  46 24   6.3   3.5
 28000 -28.8 -19.8  215  39 20   7.6   4.2 | -29.7 -21.5  215  44 23   6.3   3.5
 27000 -26.6 -15.9  215  38 19   6.9   3.8 | -27.7 -17.9  215  42 21   6.6   3.6
 26000 -24.5 -12.1  215  37 19   6.9   3.8 | -25.8 -14.4  215  39 20   6.6   3.6
 25000 -22.5  -8.5  215  36 19   6.9   3.8 | -23.8 -10.8  215  37 19   6.7   3.7
 24000 -20.4  -4.7  215  34 18   6.7   3.7 | -21.8  -7.2  215  35 18   7.3   4.0
 23000 -18.5  -1.3  210  32 16   6.7   3.7 | -19.7  -3.5  210  32 16   7.3   4.0
 22000 -16.5   2.3  205  30 15   6.7   3.7 | -17.5   0.5  210  29 15   7.3   4.0
 21000 -14.4   6.1  205  28 15   7.2   3.9 | -15.4   4.3  210  28 14   7.1   3.9
 20000 -12.3   9.9  210  28 15   7.2   4.0 | -13.3   8.1  215  28 15   7.1   3.9
 19500 -11.2  11.8  215  28 15   7.2   4.0 | -12.2  10.0  220  29 15   7.2   3.9
 19000 -10.1  13.8  220  29 15   7.3   4.0 | -11.2  11.8  220  29 15   7.2   3.9
 18500  -9.2  15.4  220  29 15   5.9   3.2 | -10.1  13.8  220  28 15   7.4   4.0
 18000  -8.3  17.1  225  30 16   6.0   3.3 |  -9.0  15.8  225  27 14   7.4   4.0
 17500  -7.4  18.7  225  31 16   6.0   3.3 |  -7.9  17.8  225  25 13   7.5   4.1
 17000  -6.2  20.8  225  29 15   6.1   3.3 |  -6.8  19.8  225  24 12   7.5   4.1
 16500  -5.4  22.3  225  28 14   6.3   3.5 |  -5.7  21.7  225  23 12   7.6   4.2
 16000  -4.5  23.9  225  26 13   6.5   3.6 |  -4.0  24.8  220  21 11   7.8   4.3
 15500  -3.6  25.5  225  24 12   6.9   3.8 |  -2.9  26.8  215  19 10   8.2   4.5
 15000  -2.5  27.5  220  22 11   8.1   4.4 |  -1.6  29.1  215  18  9   8.9   4.9
 14500  -1.4  29.5  215  20 10   8.0   4.4 |  -0.4  31.3  210  17  9   8.9   4.9
 14000  -0.1  31.8  210  18  9   9.2   5.1 |   1.0  33.8  205  16  8   9.7   5.3
 13500   1.2  34.2  205  17  9   9.1   5.0 |   2.4  36.3  205  15  8   9.6   5.3
 13000   2.6  36.7  200  16  8   9.4   5.2 |   3.8  38.8  200  15  8   9.3   5.1
 12500   4.0  39.2  200  15  8   9.4   5.2 |   5.2  41.4  200  14  7   9.3   5.1
 12000   5.4  41.7  200  15  8  10.0   5.5 |   6.7  44.1  200  14  7  10.1   5.5
 11500   6.9  44.4  195  15  8  10.1   5.6 |   8.2  46.8  200  14  7  10.2   5.6
 11000   8.4  47.1  195  14  7   8.9   4.9 |   9.6  49.3  200  13  7   8.7   4.8
 10500   9.6  49.3  195  14  7   8.6   4.7 |  10.9  51.6  200  13  7   8.6   4.7
 10250  10.3  50.5  195  14  7  10.7   5.9 |  11.6  52.9  200  13  7  10.9   6.0
 10000  11.2  52.2  195  14  7  11.4   6.2 |  12.4  54.3  200  13  6  11.1   6.1
  9750  12.0  53.6  195  14  7  10.2   5.6 |  13.2  55.8  200  12  6   9.6   5.3
  9500  12.8  55.0  195  14  7  10.7   5.9 |  13.9  57.0  200  12  6  10.4   5.7
  9250  13.5  56.3  195  14  7   9.9   5.4 |  14.7  58.5  200  12  6   9.0   4.9
  9000  14.2  57.6  195  14  7   9.6   5.3 |  15.3  59.5  200  12  6   8.7   4.8
  8750  15.0  59.0  195  14  7  10.1   5.6 |  16.0  60.8  200  11  6   9.8   5.4
  8500  15.7  60.3  195  14  7   9.6   5.3 |  16.7  62.1  205  11  5   9.2   5.0
  8250  16.5  61.7  195  14  7  11.1   6.1 |  17.5  63.5  205  10  5  10.6   5.8
  8000  17.3  63.1  195  13  7  10.8   5.9 |  18.3  64.9  205  10  5  10.8   5.9
  7750  18.1  64.6  195  13  7   9.0   4.9 |  19.0  66.2  205   9  5   9.5   5.2
  7500  18.7  65.7  195  13  7   8.9   4.9 |  19.8  67.6  205   9  4   9.8   5.4
  7250  19.4  66.9  195  13  7  10.3   5.7 |  20.5  68.9  210   8  4   9.4   5.2
  7000  20.3  68.5  195  13  7  11.4   6.2 |  21.2  70.2  210   8  4   9.2   5.0
  6750  21.0  69.8  195  13  7   9.5   5.2 |  21.9  71.4  210   7  4   9.5   5.2
  6500  21.7  71.1  190  13  6   8.8   4.8 |  22.6  72.7  215   7  4   9.6   5.3
  6250  22.4  72.3  190  12  6  10.6   5.8 |  23.3  73.9  215   7  3  10.1   5.5
  6000  23.3  73.9  190  12  6  12.0   6.6 |  24.1  75.4  215   6  3  10.4   5.7
  5750  24.2  75.6  190  11  6  11.2   6.1 |  24.9  76.8  215   5  3  10.4   5.7
  5500  25.1  77.2  190  11  5  16.6   9.1 |  25.6  78.1  220   5  2  10.4   5.7
________________________________________________________________________________

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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