Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211242
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0642 MDT Thursday, September 21, 2017

This forecast is for Thursday, September 21, 2017:

If the trigger temperature of 77.8 F/25.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 766 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14825 ft MSL (9540 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1130 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................. 14018 ft MSL (8733 ft AGL)
Thermal soaring outlook for Friday 09/22....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13914 ft MSL (8629 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 20325 ft MSL (15040 ft AGL)
Wave soaring outlook for Friday 09/22.......... Good

Remarks...

Sunrise/Sunset.................... 06:46:40 / 18:58:09 MDT
Total possible sunshine........... 12 hr 11 min 29 sec (731 min 29 sec)
Altitude of sun at 12:52:25 MDT... 50.62 degrees

Upper air data from rawinsonde observation taken on 09/21/2017 at 0600 MDT

Freezing level.................. 16286 ft MSL (11001 ft AGL)
Convective condensation level... 21773 ft MSL (16488 ft AGL)
Lifted condensation level....... 19754 ft MSL (14468 ft AGL)
Lifted index.................... +2.9
K index......................... -13.9

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.4 -82.1   260   40   20   6.7   3.7   88.2 190.8    32.8      M    M
 45000  -60.0 -76.0   240   42   22   2.4   1.3   69.1 156.4    23.3      M    M
 40000  -58.5 -73.3   240   50   26   7.2   4.0   49.0 120.3    11.6      M    M
 38000  -54.0 -65.2   235   47   24   7.4   4.1   46.5 115.7    10.2      M    M
 36000  -49.6 -57.3   230   45   23   7.4   4.1   44.6 112.3     9.1      M    M
 34000  -44.2 -47.6   225   41   21   9.9   5.4   43.1 109.5     8.3      M    M
 32000  -38.4 -37.1   230   43   22   9.6   5.3   42.9 109.3     8.4      M    M
 30000  -33.1 -27.6   235   42   22   8.6   4.7   42.5 108.5     8.2      M    M
 29000  -30.5 -22.9   235   40   21   8.6   4.7   41.8 107.2     7.8      M    M
 28000  -27.9 -18.2   235   39   20   8.6   4.7   41.2 106.2     7.5      M    M
 27000  -25.3 -13.5   240   37   19   8.6   4.7   40.8 105.4     7.2      M    M
 26000  -22.7  -8.9   240   36   18   8.6   4.7   40.5 104.9     7.0      M    M
 25000  -20.1  -4.2   240   34   18   8.6   4.7   40.3 104.5     6.9      M    M
 24000  -17.7   0.1   245   32   16   7.8   4.3   39.7 103.4     6.5      M    M
 23000  -15.3   4.5   245   34   18   7.8   4.3   38.8 101.8     5.9      M    M
 22000  -13.0   8.6   240   37   19   7.8   4.3   38.0 100.4     5.3      M    M
 21000  -10.7  12.7   240   39   20   7.7   4.2   37.4  99.3     4.8      M    M
 20000   -8.6  16.5   240   42   22   6.0   3.3   36.5  97.7     4.1      M    M
 19500   -7.6  18.3   240   41   21   6.1   3.4   35.8  96.5     3.6      M    M
 19000   -6.7  19.9   240   40   21   6.4   3.5   35.2  95.4     3.0      M    M
 18500   -5.6  21.9   240   40   20   8.1   4.4   34.8  94.6     2.7      M    M
 18000   -4.4  24.1   240   39   20   8.0   4.4   34.4  94.0     2.4      M    M
 17500   -3.2  26.2   240   39   20   8.0   4.4   34.1  93.4     2.1      M    M
 17000   -2.0  28.4   245   38   20   8.0   4.4   33.8  92.9     1.9      M    M
 16500   -0.2  31.6   245   37   19   8.0   4.4   33.5  92.2     1.5      M    M
 16000    1.0  33.8   245   36   19   8.1   4.4   33.2  91.8     1.3      M    M
 15500    2.2  36.0   250   33   17   8.7   4.8   32.9  91.2     1.0      M    M
 15000    2.9  37.2   250   29   15  -0.8  -0.5   32.1  89.7     0.3      M    M
 14500    2.5  36.5   255   26   13  -1.7  -1.0   30.1  86.3    -1.6    763  3.9
 14000    2.2  36.0   260   23   12  -2.5  -1.4   28.3  82.9    -3.4    759  3.9
 13500    2.7  36.9   255   26   13  10.1   5.5   27.3  81.2    -4.4    729  3.7
 13000    4.0  39.2   255   28   14   8.9   4.9   27.2  80.9    -4.6    675  3.4
 12500    5.3  41.5   250   30   15   8.8   4.8   27.0  80.7    -4.7    621  3.2
 12000    6.6  43.9   250   32   16   8.8   4.8   26.9  80.4    -4.9    567  2.9
 11500    7.9  46.2   250   29   15   8.8   4.8   26.7  80.1    -5.1    513  2.6
 11000    9.2  48.6   245   25   13   8.8   4.8   26.5  79.8    -5.3    459  2.3
 10500   10.5  50.9   245   22   12   8.8   4.8   26.4  79.5    -5.5    405  2.1
 10250   11.2  52.2   240   21   11   8.8   4.8   26.3  79.4    -5.6    378  1.9
 10000   11.8  53.2   240   20   10   8.6   4.7   26.3  79.3    -5.7    351  1.8
  9750   12.4  54.3   235   19   10   8.5   4.6   26.2  79.1    -5.8    325  1.7
  9500   13.1  55.6   235   19   10   8.5   4.7   26.1  79.0    -5.9    299  1.5
  9250   13.7  56.7   230   18    9   8.5   4.7   26.0  78.8    -6.0    273  1.4
  9000   14.3  57.7   230   18    9   8.5   4.7   25.9  78.7    -6.1    246  1.3
  8750   15.0  59.0   225   18    9   8.5   4.7   25.8  78.5    -6.2    220  1.1
  8500   15.6  60.1   215   19   10   8.5   4.7   25.7  78.3    -6.3    194  1.0
  8250   16.2  61.2   210   20   10   8.5   4.7   25.6  78.2    -6.4    168  0.9
  8000   16.8  62.2   205   21   11   8.5   4.7   25.6  78.0    -6.5    142  0.7
  7750   17.5  63.5   200   22   11   8.5   4.7   25.5  77.8    -6.7    115  0.6
  7500   18.1  64.6   200   23   12   8.5   4.7   25.4  77.6    -6.8     89  0.5
  7250   18.7  65.7   195   24   12   8.5   4.7   25.3  77.5    -6.9     63  0.3
  7000   19.3  66.7   195   25   13   8.5   4.7   25.2  77.3    -7.0     37  0.2
  6750   20.0  68.0   195   26   13   8.5   4.6   25.1  77.1    -7.2     11  0.1
  6500   20.6  69.1   195   27   14   8.7   4.7   25.0  76.9    -7.3      M    M
  6250   21.2  70.2   195   28   14   8.0   4.4   24.9  76.7    -7.4      M    M
  6000   21.9  71.4   195   29   15  10.5   5.7   24.8  76.6    -7.5      M    M
  5750   22.5  72.5   190   22   12   1.3   0.7   24.7  76.4    -7.7      M    M
  5500   21.3  70.3   185   15    8 -35.8 -19.6   22.8  73.0    -9.6      M    M

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

           09/21/2017 at 0900 MDT          |       09/21/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +5.5        | CAPE...     0.0    LI...       +5.4
CINH...    -0.0    K Index...  -3.9        | CINH...    -0.1    K Index...  +0.4
                                           |
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 -64.4 -83.9  245  21 11   2.1   1.2 | -63.7 -82.7  240  22 11   2.1   1.1
 45000 -61.1 -78.0  250  27 14   2.6   1.4 | -60.3 -76.5  245  29 15   3.1   1.7
 40000 -57.2 -71.0  240  25 13   4.8   2.6 | -55.6 -68.1  235  26 14   4.4   2.4
 38000 -53.1 -63.6  235  24 12   6.8   3.7 | -52.0 -61.6  235  25 13   6.1   3.3
 36000 -49.0 -56.2  230  23 12   6.8   3.7 | -47.9 -54.2  230  24 12   6.1   3.3
 34000 -43.9 -47.0  225  23 12   7.8   4.3 | -43.7 -46.7  230  23 12   7.4   4.0
 32000 -39.2 -38.6  225  22 11   7.8   4.3 | -39.2 -38.6  225  23 12   7.4   4.1
 30000 -34.3 -29.7  220  21 11   8.3   4.6 | -34.5 -30.1  220  22 11   8.1   4.4
 29000 -31.8 -25.2  220  21 11   8.4   4.6 | -32.1 -25.8  220  22 11   8.1   4.4
 28000 -29.3 -20.7  220  20 10   8.3   4.6 | -29.7 -21.5  215  21 11   8.0   4.4
 27000 -26.8 -16.2  220  20 10   8.5   4.7 | -27.2 -17.0  215  21 11   8.5   4.6
 26000 -24.3 -11.7  220  20 10   8.5   4.7 | -24.7 -12.5  210  21 11   8.5   4.6
 25000 -21.7  -7.1  215  19 10   8.5   4.7 | -22.1  -7.8  210  21 11   8.5   4.6
 24000 -19.2  -2.6  215  19 10   8.4   4.6 | -19.6  -3.3  205  20 10   8.3   4.5
 23000 -16.7   1.9  215  18  9   8.4   4.6 | -17.1   1.2  205  19 10   8.3   4.5
 22000 -14.2   6.4  215  18  9   8.4   4.6 | -14.7   5.5  205  19 10   8.3   4.6
 21000 -11.8  10.8  215  17  9   7.7   4.2 | -12.2  10.0  205  18  9   8.3   4.5
 20000  -9.5  14.9  215  17  9   7.7   4.2 |  -9.1  15.6  210  17  9   8.3   4.5
 19500  -8.4  16.9  215  17  9   7.7   4.2 |  -7.8  18.0  210  17  9   8.3   4.6
 19000  -6.6  20.1  215  16  8   7.6   4.2 |  -6.6  20.1  210  17  9   7.9   4.4
 18500  -5.5  22.1  220  16  8   7.6   4.2 |  -5.4  22.3  215  17  9   7.8   4.3
 18000  -4.4  24.1  220  16  8   7.6   4.2 |  -4.3  24.3  220  17  9   7.8   4.3
 17500  -3.3  26.1  225  16  8   7.0   3.9 |  -3.2  26.2  220  17  9   6.8   3.7
 17000  -2.2  28.0  225  16  8   7.1   3.9 |  -2.2  28.0  225  17  9   6.9   3.8
 16500  -1.2  29.8  225  16  8   7.0   3.8 |  -1.2  29.8  230  16  8   6.5   3.6
 16000  -0.1  31.8  230  16  8   6.9   3.8 |  -0.2  31.6  230  16  8   6.4   3.5
 15500   0.9  33.6  230  16  8   6.9   3.8 |   0.7  33.3  235  16  8   6.2   3.4
 15000   1.9  35.4  235  15  8   6.7   3.7 |   1.6  34.9  235  15  8   5.7   3.1
 14500   2.9  37.2  235  15  8   6.7   3.7 |   2.4  36.3  240  15  8   5.7   3.1
 14000   3.9  39.0  235  15  8   6.9   3.8 |   3.3  37.9  240  14  7   6.5   3.6
 13500   4.9  40.8  240  14  7   6.8   3.7 |   4.2  39.6  245  13  7   6.4   3.5
 13000   5.9  42.6  240  14  7   7.2   4.0 |   5.2  41.4  245  12  6   7.1   3.9
 12500   7.0  44.6  240  13  7   7.2   4.0 |   6.3  43.3  245  10  5   7.1   3.9
 12000   8.0  46.4  245  13  7   7.5   4.1 |   7.4  45.3  245   9  5   8.1   4.4
 11500   9.1  48.4  245  12  6   7.6   4.2 |   8.6  47.5  245   8  4   8.4   4.6
 11000  10.2  50.4  245  12  6   6.8   3.7 |   9.8  49.6  240   7  3   7.6   4.2
 10500  11.2  52.2  250  12  6   6.1   3.4 |  10.9  51.6  235   5  3   7.2   4.0
 10250  11.6  52.9  250  11  6   8.1   4.4 |  11.5  52.7  235   5  3  10.5   5.8
 10000  12.3  54.1  250  11  6   8.5   4.7 |  12.4  54.3  230   5  2  10.4   5.7
  9750  12.8  55.0  250  10  5   7.0   3.9 |  13.0  55.4  225   4  2   7.8   4.3
  9500  13.4  56.1  250  10  5   7.5   4.1 |  13.6  56.5  220   4  2   8.6   4.7
  9250  13.9  57.0  255  10  5   7.2   4.0 |  14.2  57.6  210   3  2   8.2   4.5
  9000  14.4  57.9  250   9  5   6.7   3.7 |  14.8  58.6  215   3  2   8.0   4.4
  8750  14.9  58.8  250   9  5   6.4   3.5 |  15.4  59.7  210   3  2   7.8   4.3
  8500  15.3  59.5  250   8  4   6.7   3.7 |  16.0  60.8  205   3  2   8.1   4.5
  8250  15.8  60.4  250   8  4   5.9   3.2 |  16.5  61.7  195   3  2   6.9   3.8
  8000  16.2  61.2  250   7  4   4.8   2.6 |  17.0  62.6  185   3  2   8.0   4.4
  7750  16.5  61.7  245   7  3   4.9   2.7 |  17.7  63.9  180   3  2  10.2   5.6
  7500  16.9  62.4  245   6  3   5.5   3.0 |  18.4  65.1  185   3  1  10.2   5.6
  7250  17.2  63.0  240   6  3   4.0   2.2 |  19.2  66.6  185   3  1   9.6   5.3
  7000  17.4  63.3  235   5  3   2.2   1.2 |  19.9  67.8  180   3  1   9.2   5.0
  6750  17.6  63.7  235   5  2   2.9   1.6 |  20.6  69.1  175   3  1  10.2   5.6
  6500  17.8  64.0  230   5  2   3.4   1.8 |  21.4  70.5  180   3  1  10.7   5.9
  6250  18.0  64.4  225   4  2   1.4   0.8 |  22.2  72.0  185   3  1  10.4   5.7
  6000  18.0  64.4  210   4  2  -0.3  -0.2 |  23.0  73.4  175   2  1  10.8   5.9
  5750  18.0  64.4  200   4  2   2.3   1.3 |  23.8  74.8  170   2  1   9.5   5.2
  5500  18.4  65.1  200   3  2   8.4   4.6 |  24.5  76.1  175   2  1  14.3   7.8

           09/21/2017 at 1500 MDT          |       09/21/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +3.0        | CAPE...     0.0    LI...       +1.6
CINH...    -0.1    K Index... +14.3        | CINH...    -0.1    K Index... +15.4
                                           |
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 -64.1 -83.4  235  23 12   2.4   1.3 | -64.9 -84.8  240  27 14   2.7   1.5
 45000 -60.0 -76.0  240  30 15   3.8   2.1 | -60.3 -76.5  250  35 18   4.4   2.4
 40000 -54.3 -65.7  240  27 14   4.7   2.6 | -53.6 -64.5  245  30 15   4.9   2.7
 38000 -50.4 -58.7  235  27 14   5.8   3.2 | -50.0 -58.0  240  29 15   5.4   3.0
 36000 -46.9 -52.4  230  26 13   5.8   3.2 | -46.7 -52.1  235  28 14   5.5   3.0
 34000 -42.9 -45.2  230  25 13   7.1   3.9 | -42.8 -45.0  230  27 14   7.0   3.9
 32000 -38.6 -37.5  230  24 13   7.1   3.9 | -38.5 -37.3  230  26 14   7.0   3.9
 30000 -34.1 -29.4  230  23 12   7.8   4.3 | -33.8 -28.8  230  25 13   8.4   4.6
 29000 -31.7 -25.1  225  23 12   7.8   4.3 | -31.3 -24.3  225  24 12   8.4   4.6
 28000 -29.4 -20.9  225  22 12   7.8   4.3 | -28.8 -19.8  225  24 12   8.4   4.6
 27000 -26.9 -16.4  225  22 11   8.4   4.6 | -26.3 -15.3  225  23 12   8.2   4.5
 26000 -24.4 -11.9  220  22 11   8.4   4.6 | -23.8 -10.8  225  22 11   8.2   4.5
 25000 -21.9  -7.4  220  21 11   8.4   4.6 | -21.4  -6.5  225  21 11   8.2   4.5
 24000 -19.4  -2.9  220  21 11   8.2   4.5 | -19.0  -2.2  225  21 11   7.5   4.1
 23000 -17.0   1.4  215  21 11   8.2   4.5 | -16.8   1.8  220  20 10   7.5   4.1
 22000 -14.5   5.9  215  20 10   8.1   4.5 | -14.5   5.9  220  19 10   7.4   4.1
 21000 -11.8  10.8  215  19 10   6.9   3.8 | -12.0  10.4  220  17  9   6.4   3.5
 20000  -9.7  14.5  215  17  9   7.0   3.8 | -10.1  13.8  225  14  7   6.5   3.6
 19500  -8.7  16.3  220  16  8   7.0   3.8 |  -9.2  15.4  230  13  7   6.5   3.6
 19000  -7.7  18.1  220  15  8   6.7   3.7 |  -8.2  17.2  230  12  6   6.8   3.7
 18500  -6.7  19.9  220  15  8   6.7   3.7 |  -7.2  19.0  230  12  6   6.9   3.8
 18000  -5.7  21.7  225  14  7   6.7   3.7 |  -6.2  20.8  230  12  6   7.0   3.8
 17500  -4.8  23.4  225  14  7   6.5   3.6 |  -5.2  22.6  230  11  6   7.4   4.1
 17000  -3.8  25.2  225  13  7   6.5   3.6 |  -4.1  24.6  230  10  5   7.4   4.1
 16500  -2.9  26.8  230  12  6   7.1   3.9 |  -3.0  26.6  225  10  5   8.2   4.5
 16000  -1.8  28.8  230  12  6   7.3   4.0 |  -1.7  28.9  220   9  5   8.6   4.7
 15500  -0.8  30.6  230  11  6   7.7   4.2 |  -0.5  31.1  215   9  5   8.7   4.8
 15000   0.5  32.9  225  10  5   8.7   4.8 |   0.9  33.6  210   9  5   9.3   5.1
 14500   1.7  35.1  220   9  5   8.6   4.7 |   2.3  36.1  210  10  5   9.3   5.1
 14000   3.1  37.6  215   8  4   9.2   5.0 |   3.7  38.7  205  10  5   9.7   5.3
 13500   4.4  39.9  215   8  4   9.1   5.0 |   5.1  41.2  205  10  5   9.6   5.3
 13000   5.8  42.4  210   7  4   9.4   5.1 |   6.6  43.9  205  10  5   9.7   5.3
 12500   7.2  45.0  205   7  4   9.4   5.1 |   8.0  46.4  205  10  5   9.7   5.3
 12000   8.6  47.5  205   7  3   9.4   5.2 |   9.5  49.1  200  10  5   9.7   5.3
 11500  10.0  50.0  200   6  3   9.4   5.2 |  10.9  51.6  200  10  5   9.6   5.3
 11000  11.4  52.5  200   6  3   8.8   4.8 |  12.4  54.3  200  10  5   9.2   5.0
 10500  12.7  54.9  200   6  3   9.0   4.9 |  13.7  56.7  200  10  5   9.3   5.1
 10250  13.5  56.3  200   6  3  11.5   6.3 |  14.5  58.1  200  10  5  11.0   6.1
 10000  14.3  57.7  195   6  3  11.4   6.3 |  15.3  59.5  195  10  5  11.2   6.1
  9750  15.1  59.2  195   6  3  10.0   5.5 |  16.1  61.0  195  10  5  10.3   5.6
  9500  15.9  60.6  195   6  3  11.0   6.0 |  16.9  62.4  195  10  5  11.3   6.2
  9250  16.7  62.1  195   6  3   8.4   4.6 |  17.7  63.9  195  10  5   8.0   4.4
  9000  17.2  63.0  195   5  3   8.1   4.5 |  18.2  64.8  195  10  5   7.4   4.1
  8750  18.0  64.4  195   5  3  10.4   5.7 |  18.9  66.0  195  10  5  10.4   5.7
  8500  18.7  65.7  195   5  3   9.8   5.4 |  19.6  67.3  195   9  5   9.6   5.3
  8250  19.5  67.1  190   5  3   9.9   5.4 |  20.4  68.7  195   9  5   9.9   5.5
  8000  20.2  68.4  195   5  3   9.9   5.4 |  21.1  70.0  195   9  5   9.8   5.4
  7750  20.9  69.6  195   5  3   9.9   5.4 |  21.8  71.2  195   9  5   9.6   5.3
  7500  21.7  71.1  190   5  2  10.0   5.5 |  22.6  72.7  190   9  5   9.8   5.4
  7250  22.4  72.3  190   5  2   9.6   5.3 |  23.3  73.9  190   9  5   9.4   5.2
  7000  23.1  73.6  190   5  2   9.5   5.2 |  24.0  75.2  190   9  5   9.1   5.0
  6750  23.9  75.0  195   5  2  10.3   5.7 |  24.7  76.5  190   9  4   9.6   5.3
  6500  24.7  76.5  190   4  2  10.7   5.9 |  25.4  77.7  190   8  4   9.9   5.4
  6250  25.5  77.9  190   4  2  10.5   5.8 |  26.1  79.0  190   8  4  10.0   5.5
  6000  26.3  79.3  190   4  2  11.0   6.0 |  26.9  80.4  190   8  4  10.3   5.7
  5750  27.1  80.8  190   4  2   9.2   5.0 |  27.7  81.9  190   7  4   9.3   5.1
  5500  27.8  82.0  190   4  2  13.6   7.4 |  28.3  82.9  190   6  3   8.1   4.5
________________________________________________________________________________

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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