Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220127
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1859 MDT Tuesday, September 20, 2016

This forecast is for Wednesday, September 21, 2016:

If the trigger temperature of 78.0 F/25.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 592 ft/min (3.0 m/s)
   Maximum height of thermals.................. 15945 ft MSL (10638 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9003 ft MSL (3696 ft AGL)
Thermal soaring outlook for Thursday 09/22..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change.
Height of stable layer (12-18K ft MSL)......... 15865 ft MSL (10558 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 17093 ft MSL (11786 ft AGL)
Wave soaring outlook for Thursday 09/22........ Poor

Remarks...

Sunrise/Sunset.................... 06:46:40 / 18:58:51 MDT
Total possible sunshine........... 12 hr 12 min 11 sec (732 min 11 sec)
Altitude of sun at 12:52:16 MDT... 50.55 degrees

Upper air data from numerical model forecast valid on 09/21/2016 at 0600 MDT

Freezing level.................. 13863 ft MSL (8556 ft AGL)
Convective condensation level... 15288 ft MSL (9981 ft AGL)
Lifted condensation level....... 15948 ft MSL (10642 ft AGL)
Lifted index.................... +3.2
K index......................... +22.4

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  -66.1 -87.0   265   44   22   2.4   1.3      M     M       M      M    M
 45000  -61.6 -78.9   260   51   26   4.7   2.6      M     M       M      M    M
 40000  -53.8 -64.8   260   54   28   6.9   3.8      M     M       M      M    M
 38000  -49.7 -57.5   250   51   26   7.0   3.8      M     M       M      M    M
 36000  -45.5 -49.9   245   48   25   6.7   3.7      M     M       M      M    M
 34000  -40.2 -40.4   240   38   20   9.2   5.1      M     M       M      M    M
 32000  -34.6 -30.3   235   27   14   9.1   5.0      M     M       M      M    M
 30000  -29.4 -20.9   240   29   15   8.6   4.7   47.4 117.3    14.4      M    M
 29000  -26.3 -15.3   245   33   17   8.6   4.7   46.9 116.4    14.2      M    M
 28000  -23.8 -10.8   245   36   18   7.3   4.0   46.5 115.7    14.0      M    M
 27000  -21.7  -7.1   245   34   18   7.0   3.8   45.3 113.6    13.2      M    M
 26000  -19.7  -3.5   240   33   17   7.0   3.9   44.3 111.7    12.5      M    M
 25000  -17.6   0.3   240   32   16   7.0   3.9   43.4 110.1    11.9      M    M
 24000  -15.7   3.7   240   31   16   6.7   3.7   42.2 108.0    11.0      M    M
 23000  -13.7   7.3   240   31   16   6.7   3.7   41.1 105.9    10.1      M    M
 22000  -11.8  10.8   240   31   16   6.6   3.6   40.1 104.1     9.3      M    M
 21000  -10.1  13.8   240   32   16   5.6   3.1   38.6 101.4     8.1      M    M
 20000   -8.5  16.7   240   32   17   5.6   3.1   37.1  98.8     6.9      M    M
 19500   -7.7  18.1   240   33   17   5.6   3.1   36.4  97.5     6.3      M    M
 19000   -6.9  19.6   240   34   17   5.3   2.9   35.7  96.3     5.7      M    M
 18500   -6.2  20.8   235   35   18   5.3   2.9   34.9  94.9     5.0      M    M
 18000   -5.4  22.3   235   37   19   5.1   2.8   34.2  93.5     4.3      M    M
 17500   -4.8  23.4   230   37   19   3.7   2.0   33.2  91.8     3.5      M    M
 17000   -4.2  24.4   230   38   20   3.9   2.1   32.2  90.0     2.6      M    M
 16500   -3.8  25.2   225   39   20   1.9   1.1   31.1  88.0     1.7      M    M
 16000   -3.6  25.5   220   38   20   1.5   0.8   29.7  85.5     0.4      M    M
 15500   -3.3  26.1   215   37   19   2.3   1.3   28.3  83.0    -0.8    978  5.0
 15000   -2.5  27.5   210   35   18   3.9   2.1   26.8  80.3    -2.2    931  4.7
 14500   -1.8  28.8   210   33   17   8.5   4.7   26.0  78.9    -2.9    894  4.5
 14000   -0.1  31.8   205   32   16  10.7   5.9   26.2  79.2    -2.7    830  4.2
 13500    1.5  34.7   205   30   16  11.2   6.1   26.4  79.5    -2.6    766  3.9
 13000    3.3  37.9   205   29   15  11.6   6.4   26.7  80.0    -2.3    698  3.5
 12500    5.1  41.2   205   28   14  11.3   6.2   27.0  80.6    -1.9    630  3.2
 12000    6.6  43.9   205   27   14  10.1   5.5   27.1  80.8    -1.8    569  2.9
 11500    8.1  46.6   205   25   13   9.8   5.4   27.2  80.9    -1.8    508  2.6
 11000    9.4  48.9   210   25   13   7.8   4.3   27.0  80.6    -2.0    455  2.3
 10500   10.7  51.3   215   24   12   4.5   2.5   26.8  80.2    -2.2    404  2.0
 10250   10.9  51.6   215   23   12   6.1   3.3   26.2  79.2    -2.7    390  2.0
 10000   11.6  52.9   220   24   12  11.9   6.5   26.3  79.3    -2.7    359  1.8
  9750   12.4  54.3   225   25   13  11.0   6.0   26.4  79.5    -2.6    328  1.7
  9500   13.2  55.8   225   26   13   9.9   5.4   26.5  79.7    -2.6    297  1.5
  9250   13.8  56.8   230   26   13   6.5   3.6   26.4  79.5    -2.7    272  1.4
  9000   14.2  57.6   235   25   13   6.4   3.5   26.1  78.9    -3.0    252  1.3
  8750   14.7  58.5   235   24   13   7.4   4.1   25.9  78.6    -3.3    229  1.2
  8500   15.2  59.4   240   23   12   6.5   3.6   25.7  78.2    -3.5    207  1.1
  8250   15.7  60.3   245   21   11   5.7   3.1   25.4  77.7    -3.8    187  1.0
  8000   16.0  60.8   245   19   10   5.2   2.9   25.0  77.1    -4.2    169  0.9
  7750   16.4  61.5   250   16    8   4.2   2.3   24.7  76.4    -4.6    151  0.8
  7500   16.7  62.1   255   13    7   5.7   3.2   24.3  75.7    -5.0    134  0.7
  7250   17.2  63.0   260   12    6   7.3   4.0   24.1  75.3    -5.2    111  0.6
  7000   17.7  63.9   265   10    5   6.9   3.8   23.8  74.9    -5.4     89  0.4
  6750   18.2  64.8   270    8    4   6.5   3.5   23.6  74.5    -5.7     67  0.3
  6500   18.6  65.5   275    7    4   5.9   3.3   23.3  74.0    -6.0     46  0.2
  6250   19.1  66.4   270    6    3   5.7   3.1   23.0  73.5    -6.3     26  0.1
  6000   19.5  67.1   265    6    3   6.4   3.5   22.8  73.0    -6.6      6  0.0
  5750   19.9  67.8   260    5    3   4.0   2.2   22.5  72.4    -6.9      M    M
  5500   20.0  68.0   240    4    2  -2.3  -1.2   21.8  71.2    -7.6      M    M

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

           09/21/2016 at 0900 MDT          |       09/21/2016 at 1200 MDT
                                           |
K index... +25.7  LI... +2.1               | K index... +26.8  LI... +2.1
CAPE... 0.0  CIN... -0.1                   | CAPE... 0.0  CIN... M
                                           |
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 -65.7 -86.3  265  43 22   2.3   1.3 | -65.2 -85.4  265  40 20   2.9   1.6
 45000 -61.3 -78.3  265  51 26   4.6   2.5 | -59.9 -75.8  260  47 24   4.6   2.5
 40000 -53.7 -64.7  250  48 25   6.9   3.8 | -52.7 -62.9  255  49 25   6.1   3.4
 38000 -49.6 -57.3  245  43 22   6.9   3.8 | -49.0 -56.2  250  50 26   6.2   3.4
 36000 -45.4 -49.7  235  39 20   6.7   3.7 | -45.3 -49.5  240  52 27   5.9   3.2
 34000 -40.0 -40.0  235  38 19   9.3   5.1 | -40.0 -40.0  235  47 24   9.3   5.1
 32000 -34.5 -30.1  240  36 19   9.1   5.0 | -34.5 -30.1  225  42 22   9.0   5.0
 30000 -29.5 -21.1  250  34 17   8.1   4.4 | -29.0 -20.2  230  37 19   7.8   4.3
 29000 -26.5 -15.7  255  33 17   8.1   4.4 | -26.7 -16.1  235  35 18   7.9   4.3
 28000 -24.2 -11.6  260  32 16   7.6   4.2 | -24.4 -11.9  240  34 17   7.0   3.8
 27000 -22.0  -7.6  255  32 16   7.5   4.1 | -22.4  -8.3  245  32 16   6.6   3.6
 26000 -19.8  -3.6  250  32 16   7.5   4.1 | -20.4  -4.7  250  30 16   6.6   3.6
 25000 -17.5   0.5  250  32 16   7.5   4.1 | -18.5  -1.3  255  29 15   6.7   3.6
 24000 -15.6   3.9  250  31 16   6.6   3.6 | -16.3   2.7  255  28 15   7.5   4.1
 23000 -13.6   7.5  250  29 15   6.7   3.7 | -14.1   6.6  255  28 14   7.5   4.1
 22000 -11.7  10.9  250  28 14   6.6   3.6 | -11.8  10.8  260  28 14   7.5   4.1
 21000  -9.9  14.2  255  27 14   5.9   3.2 | -10.0  14.0  255  27 14   6.3   3.4
 20000  -8.2  17.2  255  26 13   6.0   3.3 |  -8.2  17.2  250  25 13   6.3   3.5
 19500  -7.4  18.7  255  25 13   6.0   3.3 |  -7.3  18.9  250  25 13   6.4   3.5
 19000  -6.5  20.3  255  25 13   5.3   2.9 |  -6.4  20.5  250  24 12   5.4   3.0
 18500  -5.8  21.6  255  24 12   5.1   2.8 |  -5.7  21.7  250  23 12   5.2   2.9
 18000  -5.1  22.8  260  23 12   5.1   2.8 |  -5.0  23.0  250  22 11   5.2   2.8
 17500  -4.3  24.3  260  23 12   5.3   2.9 |  -4.3  24.3  250  21 11   4.6   2.5
 17000  -3.6  25.5  260  22 11   5.3   2.9 |  -3.6  25.5  250  20 10   4.6   2.5
 16500  -2.8  27.0  260  22 11   5.4   3.0 |  -2.9  26.8  250  19 10   5.0   2.8
 16000  -2.0  28.4  255  22 11   5.4   3.0 |  -1.8  28.8  250  17  9   5.1   2.8
 15500  -0.9  30.4  255  22 11   4.5   2.4 |  -1.1  30.0  250  16  8   5.9   3.2
 15000  -0.3  31.5  250  22 11   4.4   2.4 |  -0.2  31.6  250  15  8   6.0   3.3
 14500   0.3  32.5  245  22 11   5.1   2.8 |   0.7  33.3  250  14  7   6.3   3.4
 14000   1.1  34.0  240  21 11   5.6   3.0 |   1.6  34.9  250  13  7   6.5   3.5
 13500   2.0  35.6  235  21 11   6.0   3.3 |   2.6  36.7  250  12  6   6.5   3.6
 13000   2.9  37.2  225  21 11   6.7   3.7 |   3.6  38.5  255  12  6   6.7   3.7
 12500   3.9  39.0  220  21 11   6.5   3.6 |   4.5  40.1  255  11  6   6.8   3.7
 12000   4.7  40.5  215  21 11   5.3   2.9 |   5.6  42.1  255  11  5   7.4   4.1
 11500   5.5  41.9  210  22 11   5.4   3.0 |   6.7  44.1  250  10  5   7.4   4.1
 11000   6.4  43.5  205  21 11   6.5   3.6 |   7.8  46.0  245  10  5   7.7   4.2
 10500   7.4  45.3  200  21 11   4.6   2.5 |   9.0  48.2  240  10  5   5.3   2.9
 10250   7.6  45.7  200  21 11   4.1   2.3 |   9.2  48.6  240  10  5   5.1   2.8
 10000   8.1  46.6  200  21 11   8.1   4.5 |   9.8  49.6  240   9  5   9.0   4.9
  9750   8.8  47.8  200  21 11   9.2   5.0 |  10.5  50.9  235   9  5   8.9   4.9
  9500   9.4  48.9  200  21 11   8.4   4.6 |  11.1  52.0  230   8  4   8.4   4.6
  9250  10.0  50.0  200  21 11   6.6   3.6 |  11.6  52.9  230   8  4   6.5   3.6
  9000  10.4  50.7  200  20 10   7.1   3.9 |  12.1  53.8  225   8  4   7.0   3.9
  8750  11.0  51.8  200  20 10   8.2   4.5 |  12.7  54.9  225   7  4   8.1   4.4
  8500  11.6  52.9  205  20 10   7.8   4.3 |  13.3  55.9  225   7  4   8.0   4.4
  8250  12.2  54.0  205  19 10   7.5   4.1 |  13.9  57.0  225   6  3   8.4   4.6
  8000  12.8  55.0  205  19 10   7.7   4.2 |  14.5  58.1  225   6  3   8.7   4.8
  7750  13.3  55.9  205  18  9   7.8   4.3 |  15.2  59.4  220   6  3   8.9   4.9
  7500  13.9  57.0  205  17  9   8.7   4.8 |  15.9  60.6  220   6  3   9.5   5.2
  7250  14.6  58.3  205  16  8   9.5   5.2 |  16.6  61.9  225   6  3  10.0   5.5
  7000  15.3  59.5  210  16  8   9.2   5.0 |  17.4  63.3  225   6  3  10.0   5.5
  6750  16.0  60.8  210  15  8   8.8   4.8 |  18.1  64.6  225   6  3  10.6   5.8
  6500  16.7  62.1  210  13  7   8.7   4.8 |  18.9  66.0  230   6  3  10.8   5.9
  6250  17.4  63.3  210  11  6   9.1   5.0 |  19.7  67.5  230   5  3  11.2   6.1
  6000  18.1  64.6  215   9  5   8.5   4.7 |  20.5  68.9  230   5  3   9.7   5.3
  5750  18.7  65.7  220   7  4   8.6   4.7 |  21.3  70.3  230   5  3  13.4   7.4
  5500  19.4  66.9  220   5  2  10.5   5.8 |  22.7  72.9  235   5  3  24.9  13.6

           09/21/2016 at 1500 MDT          |       09/21/2016 at 1800 MDT
                                           |
K index... +26.8  LI... +0.8               | K index... +28.4  LI... +0.3
CAPE... 0.0  CIN... -0.2                   | CAPE... +48.3  CIN... -39.2
                                           |
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 -65.7 -86.3  260  43 22   3.2   1.7 | -66.1 -87.0  255  41 21   3.4   1.9
 45000 -60.0 -76.0  260  49 25   4.7   2.6 | -60.1 -76.2  260  47 24   4.9   2.7
 40000 -52.5 -62.5  255  43 22   6.8   3.7 | -52.4 -62.3  260  41 21   6.8   3.7
 38000 -48.5 -55.3  250  42 22   6.8   3.7 | -48.3 -54.9  260  39 20   6.9   3.8
 36000 -44.4 -47.9  250  41 21   6.7   3.7 | -44.1 -47.4  260  36 18   6.8   3.7
 34000 -39.6 -39.3  240  43 22   8.2   4.5 | -39.4 -38.9  260  33 17   8.1   4.4
 32000 -34.7 -30.5  230  48 25   8.0   4.4 | -34.6 -30.3  260  31 16   8.0   4.4
 30000 -29.3 -20.7  235  50 26   8.0   4.4 | -29.7 -21.5  255  33 17   7.1   3.9
 29000 -27.0 -16.6  235  51 26   8.0   4.4 | -27.5 -17.5  255  34 18   7.1   3.9
 28000 -24.6 -12.3  240  52 27   7.3   4.0 | -25.4 -13.7  255  35 18   7.4   4.0
 27000 -22.5  -8.5  245  46 24   7.0   3.9 | -23.2  -9.8  250  32 17   7.5   4.1
 26000 -20.4  -4.7  245  41 21   7.0   3.9 | -21.0  -5.8  250  30 15   7.6   4.2
 25000 -18.3  -0.9  250  37 19   7.0   3.9 | -18.8  -1.8  245  27 14   7.7   4.2
 24000 -16.1   3.0  255  33 17   7.6   4.2 | -16.5   2.3  245  25 13   7.5   4.1
 23000 -13.8   7.2  255  29 15   7.6   4.2 | -14.3   6.3  250  24 12   7.5   4.1
 22000 -11.6  11.1  260  26 13   7.5   4.1 | -12.0  10.4  250  23 12   7.5   4.1
 21000  -9.8  14.4  255  25 13   5.9   3.2 | -10.0  14.0  255  22 11   6.7   3.7
 20000  -8.0  17.6  255  25 13   6.0   3.3 |  -8.0  17.6  265  22 12   6.7   3.7
 19500  -7.2  19.0  255  25 13   6.0   3.3 |  -7.0  19.4  265  23 12   6.8   3.7
 19000  -6.3  20.7  255  25 13   6.2   3.4 |  -6.1  21.0  270  23 12   5.3   2.9
 18500  -5.4  22.3  255  24 12   6.3   3.5 |  -5.4  22.3  270  21 11   5.0   2.7
 18000  -4.5  23.9  255  24 12   6.3   3.4 |  -4.7  23.5  270  20 10   5.0   2.7
 17500  -3.7  25.3  255  23 12   5.0   2.7 |  -4.0  24.8  275  19 10   4.9   2.7
 17000  -3.0  26.6  255  22 11   5.1   2.8 |  -3.3  26.1  275  18  9   4.9   2.7
 16500  -2.3  27.9  255  21 11   4.7   2.6 |  -2.6  27.3  275  17  9   5.2   2.9
 16000  -1.4  29.5  260  20 10   4.5   2.4 |  -1.5  29.3  270  16  8   5.4   2.9
 15500  -0.8  30.6  260  19 10   5.6   3.1 |  -0.8  30.6  270  15  8   5.3   2.9
 15000   0.0  32.0  260  18  9   5.8   3.2 |  -0.1  31.8  265  15  8   5.5   3.0
 14500   0.8  33.4  265  18  9   6.4   3.5 |   0.6  33.1  260  14  7   7.6   4.2
 14000   1.8  35.2  265  16  8   6.9   3.8 |   1.9  35.4  255  13  6   9.1   5.0
 13500   2.8  37.0  265  15  8   7.3   4.0 |   3.2  37.8  250  11  6   9.4   5.2
 13000   4.0  39.2  265  14  7   8.2   4.5 |   4.7  40.5  245  10  5   9.9   5.4
 12500   5.2  41.4  265  12  6   8.2   4.5 |   6.1  43.0  245   8  4   9.7   5.3
 12000   6.4  43.5  270  10  5   8.6   4.7 |   7.4  45.3  240   8  4   8.2   4.5
 11500   7.7  45.9  270   9  5   8.5   4.7 |   8.6  47.5  230   7  4   8.3   4.6
 11000   8.9  48.0  270   8  4   7.6   4.2 |   9.9  49.8  230   7  3   8.5   4.7
 10500  10.1  50.2  275   6  3   4.7   2.6 |  11.2  52.2  230   6  3   5.4   3.0
 10250  10.3  50.5  275   6  3   5.7   3.1 |  11.4  52.5  230   6  3   6.1   3.4
 10000  11.0  51.8  280   6  3  10.3   5.7 |  12.2  54.0  230   5  3  10.8   5.9
  9750  11.7  53.1  285   5  3   9.2   5.0 |  12.9  55.2  230   5  2   9.6   5.3
  9500  12.4  54.3  290   5  2   9.1   5.0 |  13.6  56.5  235   4  2   9.8   5.4
  9250  13.0  55.4  295   4  2   7.6   4.1 |  14.3  57.7  235   4  2   8.7   4.8
  9000  13.6  56.5  300   4  2   8.3   4.5 |  14.9  58.8  240   3  2   7.7   4.2
  8750  14.3  57.7  300   4  2   9.2   5.1 |  15.5  59.9  255   3  1   7.7   4.2
  8500  14.9  58.8  305   4  2   9.3   5.1 |  16.1  61.0  280   2  1   7.7   4.2
  8250  15.7  60.3  310   4  2  10.6   5.8 |  16.7  62.1  305   2  1   7.7   4.2
  8000  16.5  61.7  310   4  2  10.4   5.7 |  17.3  63.1  330   3  2   8.2   4.5
  7750  17.2  63.0  310   4  2   9.6   5.2 |  17.9  64.2  335   3  2   8.5   4.7
  7500  17.9  64.2  310   4  2  10.0   5.5 |  18.6  65.5  340   4  2   9.1   5.0
  7250  18.7  65.7  310   4  2  10.5   5.8 |  19.3  66.7  340   4  2  10.2   5.6
  7000  19.5  67.1  310   4  2  10.2   5.6 |  20.1  68.2  340   4  2  10.1   5.6
  6750  20.2  68.4  310   4  2   9.3   5.1 |  20.8  69.4  340   4  2   9.5   5.2
  6500  20.9  69.6  310   4  2  10.1   5.5 |  21.5  70.7  335   4  2   9.8   5.4
  6250  21.7  71.1  305   4  2  11.4   6.3 |  22.3  72.1  335   4  2  10.4   5.7
  6000  22.5  72.5  305   4  2  10.0   5.5 |  23.0  73.4  335   4  2  10.0   5.5
  5750  23.3  73.9  305   4  2  13.3   7.3 |  23.8  74.8  335   4  2  10.8   5.9
  5500  24.7  76.5  305   4  2  24.5  13.4 |  24.7  76.5  335   4  2  13.8   7.6
________________________________________________________________________________

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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