Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 201317
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0716 MDT Tuesday, September 20, 2016

This forecast is for Tuesday, September 20, 2016:

If the trigger temperature of 85.6 F/29.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 404 ft/min (2.1 m/s)
   Maximum height of thermals.................. 11505 ft MSL (6220 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1330 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6818 ft MSL (1533 ft AGL)
Thermal soaring outlook for Wednesday 09/21.... 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....................... 16358 ft MSL (11073 ft AGL)
Wave soaring outlook for Wednesday 09/21....... Poor

Remarks...

Sunrise/Sunset.................... 06:45:43 / 19:00:30 MDT
Total possible sunshine........... 12 hr 14 min 46 sec (734 min 46 sec)
Altitude of sun at 12:52:37 MDT... 50.94 degrees

Upper air data from rawinsonde observation taken on 09/20/2016 at 0600 MDT

Freezing level.................. 16001 ft MSL (10716 ft AGL)
Convective condensation level... 20745 ft MSL (15460 ft AGL)
Lifted condensation level....... 19275 ft MSL (13989 ft AGL)
Lifted index.................... +1.3
K index......................... +14.2

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  -66.7 -88.1   270   54   28   2.9   1.6   82.5 180.5    29.8      M    M
 45000  -63.1 -81.6   270   59   30   4.9   2.7   63.0 145.4    19.9      M    M
 40000  -56.1 -69.0   275   75   38   7.7   4.2   51.2 124.1    13.4      M    M
 38000  -51.0 -59.8   270   68   35   9.3   5.1   49.9 121.8    12.9      M    M
 36000  -45.5 -49.9   265   61   31   9.0   4.9   49.6 121.3    13.1      M    M
 34000  -40.4 -40.7   260   56   29   8.8   4.8   48.5 119.2    12.5      M    M
 32000  -35.3 -31.5   255   51   26   8.4   4.6   47.7 117.8    12.2      M    M
 30000  -31.7 -25.1   255   38   20   4.5   2.5   43.7 110.7     9.5      M    M
 29000  -30.0 -22.0   245   38   19   6.7   3.7   42.2 108.0     8.5      M    M
 28000  -27.4 -17.3   245   36   19   9.2   5.0   41.7 107.1     8.2      M    M
 27000  -24.6 -12.3   250   34   18   8.9   4.9   41.6 106.8     8.2      M    M
 26000  -22.6  -8.7   250   33   17   7.1   3.9   40.5 104.8     7.4      M    M
 25000  -21.1  -6.0   255   31   16   3.2   1.8   38.6 101.6     6.0      M    M
 24000  -19.2  -2.6   260   29   15   8.7   4.8   37.4  99.2     5.0      M    M
 23000  -16.6   2.1   265   26   13   8.3   4.5   37.0  98.6     4.8      M    M
 22000  -14.1   6.6   270   24   12   6.8   3.7   36.5  97.7     4.4      M    M
 21000  -11.7  10.9   260   19   10   6.1   3.4   35.8  96.4     3.9      M    M
 20000  -10.0  14.0   245   14    7   5.9   3.2   34.3  93.7     2.7      M    M
 19500   -9.1  15.6   250   14    7   5.3   2.9   33.7  92.7     2.2      M    M
 19000   -8.0  17.6   245   13    7  11.3   6.2   33.4  92.1     1.8      M    M
 18500   -6.6  20.1   240   13    6   8.9   4.9   33.4  92.0     1.7      M    M
 18000   -5.5  22.1   230   12    6   8.1   4.4   33.1  91.5     1.4      M    M
 17500   -4.2  24.4   235   13    7   8.8   4.8   32.9  91.2     1.2      M    M
 17000   -2.9  26.8   240   14    7   8.9   4.9   32.7  90.9     1.0      M    M
 16500   -1.6  29.1   240   15    8   8.9   4.9   32.6  90.7     0.9      M    M
 16000   -0.3  31.5   245   16    8   9.1   5.0   32.5  90.5     0.8      M    M
 15500    1.1  34.0   235   15    8   9.5   5.2   32.4  90.4     0.7      M    M
 15000    3.2  37.8   220   14    7   9.4   5.2   32.4  90.3     0.7      M    M
 14500    4.6  40.3   225   14    7   9.4   5.2   32.4  90.3     0.6      M    M
 14000    6.0  42.8   230   14    7   9.4   5.2   32.3  90.2     0.6      M    M
 13500    7.4  45.3   235   13    7   9.4   5.2   32.2  90.0     0.5      M    M
 13000    8.8  47.8   240   12    6   9.4   5.2   32.2  89.9     0.5      M    M
 12500   10.2  50.4   245   11    6   9.4   5.2   32.1  89.8     0.4      M    M
 12000   11.6  52.9   250   10    5   8.8   4.8   32.1  89.8     0.4      M    M
 11500   12.7  54.9   265    6    3   5.7   3.1   31.6  88.9    -0.1    498  2.5
 11000   13.6  56.5   290    4    2   7.6   4.2   31.1  87.9    -0.6    455  2.3
 10500   14.9  58.8   340    4    2   8.3   4.6   30.8  87.5    -0.8    403  2.0
 10250   15.5  59.9   335    4    2   8.5   4.6   30.7  87.3    -0.9    377  1.9
 10000   16.1  61.0   325    5    2   8.4   4.6   30.6  87.1    -1.0    351  1.8
  9750   16.7  62.1   320    5    3   8.4   4.6   30.5  87.0    -1.1    324  1.6
  9500   17.4  63.3   315    5    3   8.4   4.6   30.4  86.8    -1.2    298  1.5
  9250   18.0  64.4   315    6    3   8.4   4.6   30.4  86.6    -1.3    272  1.4
  9000   18.6  65.5   310    6    3   8.4   4.6   30.3  86.5    -1.4    246  1.2
  8750   19.3  66.7   320    7    4   8.4   4.6   30.2  86.3    -1.5    219  1.1
  8500   19.9  67.8   325    8    4   8.4   4.6   30.1  86.1    -1.6    193  1.0
  8250   20.5  68.9   325    9    5   8.5   4.6   30.0  85.9    -1.7    167  0.8
  8000   21.2  70.2   330   10    5   8.4   4.6   29.9  85.8    -1.8    140  0.7
  7750   21.8  71.2   325   10    5   8.7   4.8   29.8  85.6    -1.9    114  0.6
  7500   22.4  72.3   320   10    5   7.6   4.2   29.7  85.4    -2.0     88  0.4
  7250   22.9  73.2   315   10    5   4.8   2.7   29.4  84.9    -2.3     67  0.3
  7000   23.2  73.8   310   10    5   7.2   3.9   29.0  84.3    -2.7     48  0.2
  6750   23.5  74.3   315    9    5  -5.9  -3.3   28.6  83.5    -3.1     32  0.2
  6500   22.2  72.0   315    7    4 -21.0 -11.5   26.6  79.9    -5.1     63  0.3
  6250   21.0  69.8   320    6    3  -6.1  -3.4   24.7  76.4    -7.1     93  0.5
  6000   20.9  69.6   330    5    3  -2.2  -1.2   23.9  75.1    -7.9     88  0.4
  5750   20.5  68.9   330    3    2  -0.2  -0.1   22.8  73.1    -9.1     92  0.5
  5500   20.8  69.4   330    2    1  -3.2  -1.7   22.3  72.1    -9.6     78  0.4

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

           09/20/2016 at 0900 MDT          |       09/20/2016 at 1200 MDT
                                           |
K index... +12.0  LI... +2.1               | K index... +13.5  LI... +2.2
CAPE... 0.0  CIN... -11.3                  | CAPE... 0.0  CIN... -0.3
                                           |
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 -65.9 -86.6  275  43 22   1.8   1.0 | -65.7 -86.3  270  40 21   2.1   1.1
 45000 -62.1 -79.8  275  59 30   4.6   2.5 | -61.9 -79.4  275  57 30   3.9   2.1
 40000 -54.5 -66.1  275  78 40   7.0   3.8 | -55.0 -67.0  270  83 43   8.0   4.4
 38000 -50.2 -58.4  275  71 37   7.0   3.9 | -50.1 -58.2  265  74 38   8.1   4.4
 36000 -46.0 -50.8  275  64 33   6.8   3.8 | -45.3 -49.5  260  65 34   8.0   4.4
 34000 -41.0 -41.8  270  58 30   8.5   4.7 | -40.1 -40.2  260  57 29   8.8   4.8
 32000 -35.9 -32.6  265  52 27   8.4   4.6 | -34.8 -30.6  260  48 25   8.6   4.7
 30000 -31.2 -24.2  255  46 24   7.8   4.3 | -29.8 -21.6  255  41 21   7.2   4.0
 29000 -28.3 -18.9  250  42 22   7.8   4.3 | -27.7 -17.9  250  38 19   7.3   4.0
 28000 -26.1 -15.0  245  40 20   4.8   2.6 | -25.6 -14.1  245  35 18   5.2   2.9
 27000 -24.7 -12.5  245  34 17   4.7   2.6 | -24.1 -11.4  245  33 17   5.1   2.8
 26000 -23.3  -9.9  250  28 15   4.8   2.6 | -22.6  -8.7  240  31 16   5.1   2.8
 25000 -21.9  -7.4  255  23 12   5.7   3.1 | -21.1  -6.0  235  29 15   5.3   2.9
 24000 -19.7  -3.5  250  22 11   7.4   4.1 | -19.5  -3.1  240  24 12   5.5   3.0
 23000 -17.5   0.5  250  21 11   7.4   4.1 | -17.8  -0.0  245  19 10   5.5   3.0
 22000 -15.3   4.5  245  20 10   7.6   4.2 | -16.2   2.8  255  15  8   6.7   3.7
 21000 -13.0   8.6  240  17  9   7.8   4.3 | -13.7   7.3  250  15  8   8.1   4.4
 20000 -10.7  12.7  235  14  7   7.8   4.3 | -11.3  11.7  245  15  8   8.1   4.4
 19500  -9.5  14.9  230  13  7   7.8   4.3 | -10.0  14.0  240  15  8   8.2   4.5
 19000  -8.4  16.9  225  12  6   7.7   4.2 |  -8.6  16.5  235  15  8  10.2   5.6
 18500  -7.3  18.9  220  11  6   7.8   4.3 |  -7.2  19.0  230  15  8  10.0   5.5
 18000  -6.2  20.8  215  11  6   9.2   5.0 |  -5.7  21.7  230  15  8   8.7   4.8
 17500  -4.8  23.4  210  10  5   9.8   5.4 |  -4.6  23.7  230  15  8   8.1   4.4
 17000  -3.3  26.1  205  10  5   9.7   5.3 |  -3.5  25.7  230  14  7   8.3   4.6
 16500  -1.9  28.6  205   9  5   8.9   4.9 |  -2.2  28.0  230  13  7   9.3   5.1
 16000  -0.5  31.1  205   9  4   9.0   5.0 |  -0.8  30.6  225  11  6   9.4   5.1
 15500   1.4  34.5  205   7  4   8.5   4.7 |   1.1  34.0  230   9  5   8.0   4.4
 15000   2.7  36.9  210   6  3   8.5   4.7 |   2.3  36.1  230   7  4   8.1   4.4
 14500   3.9  39.0  210   4  2   8.4   4.6 |   3.6  38.5  240   6  3   8.3   4.5
 14000   5.2  41.4  220   3  1   8.4   4.6 |   4.8  40.6  250   5  2   8.3   4.5
 13500   6.5  43.7  260   2  1   8.6   4.7 |   6.1  43.0  270   4  2   8.5   4.7
 13000   7.8  46.0  310   2  1   8.6   4.7 |   7.4  45.3  290   4  2   8.6   4.7
 12500   9.1  48.4  330   4  2   8.7   4.8 |   8.7  47.7  310   4  2   8.6   4.7
 12000  10.4  50.7  335   5  3   8.7   4.8 |   9.9  49.8  340   4  2   8.7   4.7
 11500  11.8  53.2  335   7  4   8.7   4.8 |  11.2  52.2  360   5  2   8.7   4.8
 11000  13.0  55.4  340   8  4   8.4   4.6 |  12.5  54.5  005   6  3   8.5   4.7
 10500  14.3  57.7  345   9  5   4.3   2.4 |  13.8  56.8  005   7  4   4.0   2.2
 10250  14.5  58.1  345   9  5   5.7   3.1 |  13.9  57.0  005   7  4   5.8   3.2
 10000  15.3  59.5  350  10  5  11.8   6.5 |  14.7  58.5  005   7  4  12.5   6.8
  9750  16.1  61.0  350  10  5  10.6   5.8 |  15.6  60.1  360   8  4  11.1   6.1
  9500  16.8  62.2  355  11  6   8.7   4.8 |  16.4  61.5  360   8  4   8.7   4.7
  9250  17.3  63.1  355  11  6   6.9   3.8 |  16.9  62.4  360   9  4   6.6   3.6
  9000  17.9  64.2  355  12  6   9.0   4.9 |  17.5  63.5  360   9  5   9.3   5.1
  8750  18.6  65.5  355  12  6   9.7   5.3 |  18.2  64.8  005   9  5  10.0   5.5
  8500  19.3  66.7  355  13  7   7.8   4.3 |  18.9  66.0  005   9  5   8.2   4.5
  8250  19.8  67.6  355  13  7   6.5   3.5 |  19.5  67.1  005  10  5   7.3   4.0
  8000  20.3  68.5  355  13  7   7.2   3.9 |  20.0  68.0  005  10  5   7.2   3.9
  7750  20.8  69.4  355  13  7   7.1   3.9 |  20.5  68.9  010  10  5   6.7   3.7
  7500  21.3  70.3  355  13  7   5.8   3.2 |  21.0  69.8  010   9  5   6.7   3.7
  7250  21.7  71.1  350  13  7   4.9   2.7 |  21.5  70.7  005   8  4   6.8   3.7
  7000  22.1  71.8  350  13  7   6.0   3.3 |  22.0  71.6  005   8  4   6.6   3.6
  6750  22.5  72.5  350  13  7   2.2   1.2 |  22.5  72.5  360   6  3   8.2   4.5
  6500  22.3  72.1  345  12  6  -3.3  -1.8 |  23.2  73.8  355   5  3  10.3   5.6
  6250  22.1  71.8  340  11  6  -2.8  -1.5 |  23.9  75.0  350   5  3  10.0   5.5
  6000  21.8  71.2  330  10  5  -5.2  -2.8 |  24.7  76.5  350   5  2  10.8   5.9
  5750  21.3  70.3  320   7  4  -5.8  -3.2 |  25.6  78.1  345   5  2  15.0   8.2
  5500  20.9  69.6  300   5  2   0.4   0.2 |  26.9  80.4  350   4  2  19.3  10.6

           09/20/2016 at 1500 MDT          |       09/20/2016 at 1800 MDT
                                           |
K index... +8.9  LI... +1.6                | K index... +14.1  LI... +1.2
CAPE... 0.0  CIN... -0.0                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -66.2 -87.2  270  43 22   2.3   1.2 | -67.1 -88.8  270  45 23   1.8   1.0
 45000 -62.3 -80.1  270  57 29   3.5   1.9 | -62.6 -80.7  275  66 34   5.1   2.8
 40000 -55.6 -68.1  265  69 35   9.5   5.2 | -54.4 -65.9  275  83 43   8.5   4.7
 38000 -49.9 -57.8  265  66 34   9.6   5.3 | -49.3 -56.7  270  77 40   8.5   4.7
 36000 -44.1 -47.4  260  64 33   9.6   5.3 | -44.2 -47.6  270  72 37   8.5   4.7
 34000 -38.9 -38.0  260  57 29   8.6   4.7 | -39.2 -38.6  265  64 33   8.3   4.6
 32000 -33.7 -28.7  260  49 25   8.5   4.6 | -34.2 -29.6  260  56 29   8.1   4.5
 30000 -28.8 -19.8  260  46 24   7.2   3.9 | -28.9 -20.0  265  52 27   7.9   4.3
 29000 -26.7 -16.1  260  45 23   7.2   3.9 | -26.5 -15.7  265  50 26   7.9   4.4
 28000 -24.7 -12.5  260  43 22   4.7   2.6 | -24.2 -11.6  265  48 25   6.1   3.4
 27000 -23.3  -9.9  260  38 20   4.6   2.5 | -22.5  -8.5  265  44 23   6.0   3.3
 26000 -22.0  -7.6  255  33 17   4.6   2.5 | -20.7  -5.3  270  40 20   6.0   3.3
 25000 -20.6  -5.1  250  29 15   5.1   2.8 | -19.0  -2.2  270  35 18   5.6   3.1
 24000 -18.8  -1.8  250  30 16   6.4   3.5 | -17.7   0.1  265  33 17   4.1   2.2
 23000 -16.9   1.6  250  33 17   6.4   3.5 | -16.5   2.3  260  30 16   4.1   2.2
 22000 -15.0   5.0  250  35 18   6.6   3.6 | -15.3   4.5  260  28 14   5.0   2.8
 21000 -13.0   8.6  245  29 15   6.8   3.7 | -13.3   8.1  250  28 14   6.9   3.8
 20000 -11.0  12.2  240  23 12   6.8   3.7 | -11.3  11.7  245  28 15   6.9   3.8
 19500 -10.0  14.0  235  20 10   6.7   3.7 | -10.2  13.6  240  29 15   6.7   3.7
 19000  -8.8  16.2  235  18 10   8.7   4.7 |  -9.1  15.6  240  27 14   8.7   4.8
 18500  -7.5  18.5  235  18  9   8.5   4.6 |  -7.9  17.8  235  24 12   8.5   4.7
 18000  -6.3  20.7  240  17  9   7.6   4.2 |  -6.6  20.1  235  21 11   8.4   4.6
 17500  -5.3  22.5  240  16  8   6.9   3.8 |  -5.4  22.3  235  20 10   8.2   4.5
 17000  -4.3  24.3  235  15  8   6.9   3.8 |  -4.2  24.4  235  19 10   8.2   4.5
 16500  -3.1  26.4  235  14  7   8.2   4.5 |  -2.9  26.8  235  19 10   8.6   4.7
 16000  -1.9  28.6  235  14  7   8.0   4.4 |  -1.7  28.9  230  19 10   8.6   4.7
 15500   0.2  32.4  235  13  7   9.9   5.4 |   0.4  32.7  230  18  9   9.6   5.2
 15000   1.7  35.1  235  13  7   9.8   5.4 |   1.8  35.2  230  18  9   9.5   5.2
 14500   3.2  37.8  240  12  6  10.2   5.6 |   3.2  37.8  235  17  9   9.6   5.3
 14000   4.7  40.5  240  11  6  10.2   5.6 |   4.7  40.5  235  16  8   9.6   5.3
 13500   6.2  43.2  245  10  5   9.3   5.1 |   6.1  43.0  235  15  8   9.6   5.3
 13000   7.6  45.7  250   9  5   9.2   5.0 |   7.5  45.5  235  14  7   9.5   5.2
 12500   8.9  48.0  255   8  4   9.1   5.0 |   8.9  48.0  240  13  7   9.2   5.1
 12000  10.3  50.5  255   7  4   9.1   5.0 |  10.3  50.5  240  12  6   8.9   4.9
 11500  11.6  52.9  255   5  3   8.9   4.9 |  11.6  52.9  240  11  6   8.9   4.9
 11000  12.9  55.2  260   4  2   8.4   4.6 |  12.9  55.2  240   9  5   8.6   4.7
 10500  14.2  57.6  265   3  2   4.0   2.2 |  14.3  57.7  245   8  4   4.2   2.3
 10250  14.3  57.7  270   3  2   5.2   2.9 |  14.4  57.9  245   7  4   5.7   3.1
 10000  15.1  59.2  280   3  2  12.0   6.6 |  15.3  59.5  245   7  3  12.5   6.9
  9750  15.8  60.4  290   3  1  10.8   5.9 |  16.1  61.0  250   6  3  11.1   6.1
  9500  16.6  61.9  305   3  2   8.8   4.8 |  17.0  62.6  250   5  3   9.9   5.4
  9250  17.1  62.8  305   3  2   7.0   3.8 |  17.6  63.7  255   5  3   8.1   4.4
  9000  17.7  63.9  310   3  2   9.4   5.2 |  18.2  64.8  255   5  2   9.2   5.1
  8750  18.5  65.3  315   3  2   9.9   5.4 |  19.0  66.2  260   4  2   9.6   5.3
  8500  19.2  66.6  315   3  2   9.6   5.3 |  19.7  67.5  260   4  2   9.2   5.0
  8250  19.9  67.8  315   3  2   9.6   5.3 |  20.4  68.7  265   3  2   8.9   4.9
  8000  20.6  69.1  315   3  2   9.5   5.2 |  21.0  69.8  270   3  2   8.6   4.7
  7750  21.3  70.3  315   3  2   9.5   5.2 |  21.6  70.9  275   3  1   8.2   4.5
  7500  22.0  71.6  315   3  2   9.7   5.3 |  22.3  72.1  280   3  1   8.8   4.8
  7250  22.7  72.9  315   3  2   9.7   5.3 |  22.9  73.2  285   3  1   9.2   5.0
  7000  23.5  74.3  315   3  2  10.0   5.5 |  23.6  74.5  290   3  1   9.0   4.9
  6750  24.2  75.6  310   3  2  10.6   5.8 |  24.2  75.6  285   3  2   9.2   5.1
  6500  25.0  77.0  310   3  2  10.4   5.7 |  24.9  76.8  285   3  2   9.9   5.4
  6250  25.8  78.4  310   3  2  10.8   5.9 |  25.7  78.3  285   3  2  10.4   5.7
  6000  26.6  79.9  310   3  2   8.9   4.9 |  26.4  79.5  290   3  2   9.7   5.3
  5750  27.2  81.0  310   4  2  12.5   6.9 |  27.1  80.8  290   3  2   9.5   5.2
  5500  28.6  83.5  310   3  2  24.0  13.1 |  27.9  82.2  290   3  2  11.3   6.2
________________________________________________________________________________

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.

CIN (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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