Soaring Guidance
Issued by NWS Denver/Boulder, CO

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619
UXUS97 KBOU 220123
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0638 MDT Thursday, July 21, 2016

This forecast is for Thursday, July 21, 2016:

If the trigger temperature of 86.1 F/30.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 890 ft/min (4.5 m/s)
   Maximum height of thermals.................. 15579 ft MSL (10294 ft AGL)

Forecast maximum temperature................... 95.0 F/35.5 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13629 ft MSL (8344 ft AGL)
Thermal soaring outlook for Friday 07/22....... Excellent

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)................ Weak PVA
Potential height of wave....................... 14875 ft MSL (9590 ft AGL)
Wave soaring outlook for Friday 07/22.......... Poor

Remarks...

Sunrise/Sunset.................... 05:49:18 / 20:22:44 MDT
Total possible sunshine........... 14 hr 33 min 26 sec (873 min 26 sec)
Altitude of sun at 13:05:53 MDT... 70.47 degrees

Upper air data from rawinsonde observation taken on 07/21/2016 at 0600 MDT

Freezing level.................. 17318 ft MSL (12033 ft AGL)
Convective condensation level... 17123 ft MSL (11838 ft AGL)
Lifted condensation level....... 16852 ft MSL (11566 ft AGL)
Lifted index.................... -1.8
K index......................... +22.6

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  -67.1 -88.8   260   15    8   8.3   4.6   79.3 174.8    25.9      M    M
 45000  -61.3 -78.3   170   13    7   6.4   3.5   64.8 148.6    18.7      M    M
 40000  -52.1 -61.8   225   16    8   9.1   5.0   55.3 131.6    13.7      M    M
 38000  -46.6 -51.9   220   17    9   9.0   4.9   54.7 130.5    13.6      M    M
 36000  -41.3 -42.3   225   16    8   8.3   4.5   54.0 129.2    13.5      M    M
 34000  -37.1 -34.8   250   13    6   8.1   4.4   51.8 125.2    12.2      M    M
 32000  -32.1 -25.8   240   11    6   6.5   3.6   50.6 123.0    11.6      M    M
 30000  -27.3 -17.1   265   11    6   8.9   4.9   49.3 120.7    10.8      M    M
 29000  -24.1 -11.4   250   10    5   7.9   4.3   48.7 119.6    10.5      M    M
 28000  -21.8  -7.2   240    9    5   8.4   4.6   48.0 118.4    10.1      M    M
 27000  -20.3  -4.5   225    9    5   8.5   4.6   46.3 115.3     8.7      M    M
 26000  -17.9  -0.2   225   11    6   6.8   3.7   45.6 114.0     8.3      M    M
 25000  -16.2   2.8   225   12    6   5.1   2.8   44.2 111.6     7.2      M    M
 24000  -14.0   6.8   225   13    7   8.1   4.4   43.3 109.9     6.5      M    M
 23000  -11.6  11.1   225   13    7   8.1   4.5   42.7 108.8     6.0      M    M
 22000   -9.6  14.7   225   14    7   6.4   3.5   41.7 107.1     5.3      M    M
 21000   -7.7  18.1   250   12    6   6.4   3.5   40.5 104.8     4.2      M    M
 20000   -5.9  21.4   275   13    7   6.3   3.4   39.3 102.8     3.2      M    M
 19500   -4.9  23.2   270   14    7   4.6   2.5   38.7 101.7     2.7      M    M
 19000   -4.1  24.6   270   15    8   8.5   4.7   38.0 100.4     2.1      M    M
 18500   -2.9  26.8   265   15    8   7.9   4.3   37.6  99.8     1.7      M    M
 18000   -1.8  28.8   265   16    8   7.9   4.3   37.3  99.1     1.4      M    M
 17500   -0.6  30.9   265   17    9   7.9   4.3   37.0  98.5     1.1      M    M
 17000    0.5  32.9   260   17    9   7.9   4.3   36.7  98.0     0.8      M    M
 16500    1.7  35.1   260   18    9   7.9   4.3   36.4  97.5     0.6      M    M
 16000    2.9  37.2   260   19   10   7.9   4.3   36.1  97.1     0.3      M    M
 15500    4.0  39.2   260   16    8   7.6   4.2   35.8  96.5     0.0      M    M
 15000    4.8  40.6   265   12    6   3.8   2.1   35.1  95.1    -0.7    856  4.3
 14500    5.6  42.1   270    6    3   4.1   2.2   33.7  92.6    -2.1    810  4.1
 14000    6.2  43.2   295    3    2   7.5   4.1   32.9  91.2    -2.9    775  3.9
 13500    7.5  45.5   315    5    3   8.7   4.8   32.7  90.9    -3.1    721  3.7
 13000    8.8  47.8   325    7    4   8.8   4.8   32.6  90.6    -3.2    667  3.4
 12500   10.2  50.4   330    9    5   8.8   4.8   32.4  90.4    -3.4    613  3.1
 12000   11.5  52.7   330   11    6   8.8   4.8   32.3  90.2    -3.5    559  2.8
 11500   12.8  55.0   335   11    5   8.9   4.9   32.1  89.9    -3.7    505  2.6
 11000   14.0  57.2   340   10    5   8.1   4.5   31.9  89.5    -3.9    452  2.3
 10500   15.2  59.4   345   10    5   8.5   4.7   31.7  89.1    -4.2    403  2.0
 10250   15.8  60.4   345   10    5   8.6   4.7   31.6  88.9    -4.4    376  1.9
 10000   16.5  61.7   340   11    6   8.6   4.7   31.5  88.7    -4.5    350  1.8
  9750   17.1  62.8   340   11    6   8.6   4.7   31.4  88.6    -4.6    324  1.6
  9500   17.7  63.9   340   11    6   8.6   4.7   31.4  88.5    -4.7    298  1.5
  9250   18.3  64.9   335   12    6   8.6   4.7   31.3  88.3    -4.8    272  1.4
  9000   19.0  66.2   335   12    6   8.6   4.7   31.2  88.2    -4.9    245  1.2
  8750   19.6  67.3   330   10    5   8.6   4.7   31.1  88.0    -5.0    219  1.1
  8500   20.2  68.4   330    9    5   8.6   4.7   31.0  87.9    -5.1    193  1.0
  8250   20.9  69.6   325    7    4   8.7   4.8   31.0  87.7    -5.2    167  0.8
  8000   21.5  70.7   315    6    3   8.5   4.7   30.9  87.6    -5.3    140  0.7
  7750   22.1  71.8   300    6    3   9.2   5.0   30.8  87.4    -5.4    114  0.6
  7500   22.7  72.9   285    6    3   6.6   3.6   30.7  87.2    -5.5     88  0.4
  7250   23.1  73.6   270    7    4   3.6   2.0   30.3  86.5    -6.0     71  0.4
  7000   23.3  73.9   260    8    4   4.2   2.3   29.8  85.7    -6.4     55  0.3
  6750   23.6  74.5   260    8    4   3.4   1.9   29.4  84.9    -6.9     40  0.2
  6500   23.9  75.0   265    9    5   6.0   3.3   29.0  84.1    -7.4     24  0.1
  6250   24.2  75.6   265    9    5  -3.5  -1.9   28.5  83.4    -7.8      8  0.0
  6000   23.4  74.1   265   10    5 -11.3  -6.2   27.0  80.6    -9.4     25  0.1
  5750   22.5  72.5   250    7    4 -16.9  -9.3   25.4  77.8   -11.0     45  0.2
  5500   20.3  68.5   215    5    3 -32.8 -18.0   22.8  73.0   -13.9    102  0.5

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

           07/21/2016 at 0900 MDT          |       07/21/2016 at 1200 MDT
                                           |
K index... +25.1  LI... -2.6               | K index... +24.4  LI... -1.2
CAPE... +421.8  CIN... -96.9               | CAPE... +50.9  CIN... -27.8
                                           |
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 -65.0 -85.0  230  12  6   1.6   0.9 | -65.1 -85.2  240  16  8   1.7   0.9
 45000 -60.2 -76.4  225  14  7   5.3   2.9 | -60.3 -76.5  235  19 10   5.1   2.8
 40000 -51.6 -60.9  240  11  6   7.6   4.2 | -51.7 -61.1  240  14  7   8.2   4.5
 38000 -47.1 -52.8  245  11  6   7.6   4.2 | -46.8 -52.2  245  13  7   8.2   4.5
 36000 -42.4 -44.3  250  11  6   8.8   4.8 | -41.9 -43.4  245  12  6   8.4   4.6
 34000 -37.1 -34.8  255  11  5   9.0   4.9 | -36.8 -34.2  255  11  5   8.5   4.6
 32000 -31.7 -25.1  255  11  5   9.3   5.1 | -31.1 -24.0  260  10  5   8.7   4.8
 30000 -26.7 -16.1  245  12  6   7.5   4.1 | -26.3 -15.3  255  12  6   8.1   4.4
 29000 -24.4 -11.9  245  13  6   7.5   4.1 | -24.0 -11.2  255  13  7   8.1   4.4
 28000 -22.3  -8.1  240  13  7   7.1   3.9 | -21.7  -7.1  255  14  7   6.9   3.8
 27000 -20.2  -4.4  240  14  7   7.1   3.9 | -19.7  -3.5  250  15  8   6.9   3.8
 26000 -18.1  -0.6  240  15  8   7.1   3.9 | -17.7   0.1  250  16  8   6.9   3.8
 25000 -16.0   3.2  240  15  8   6.5   3.6 | -15.7   3.7  250  17  9   6.3   3.4
 24000 -14.1   6.6  240  15  8   6.5   3.6 | -13.8   7.2  250  16  8   6.3   3.5
 23000 -12.2  10.0  240  14  7   6.6   3.6 | -12.0  10.4  250  15  8   6.3   3.5
 22000 -10.3  13.5  240  14  7   6.0   3.3 | -10.2  13.6  250  15  8   5.9   3.2
 21000  -8.6  16.5  245  13  7   6.0   3.3 |  -8.5  16.7  245  14  7   5.9   3.2
 20000  -6.9  19.6  250  13  7   6.1   3.3 |  -6.7  19.9  245  13  7   6.0   3.3
 19500  -6.0  21.2  250  13  7   6.3   3.4 |  -5.9  21.4  245  12  6   6.2   3.4
 19000  -5.0  23.0  250  13  6   6.5   3.6 |  -4.9  23.2  245  12  6   6.4   3.5
 18500  -4.1  24.6  250  12  6   6.5   3.6 |  -4.0  24.8  245  11  6   6.4   3.5
 18000  -3.1  26.4  250  12  6   7.3   4.0 |  -3.0  26.6  245  10  5   7.0   3.8
 17500  -2.1  28.2  250  12  6   7.3   4.0 |  -2.0  28.4  245  10  5   7.0   3.9
 17000  -1.0  30.2  250  11  6   7.6   4.1 |  -1.0  30.2  245   9  5   7.3   4.0
 16500   0.2  32.4  250  11  6   8.0   4.4 |   0.7  33.3  245   7  4   7.7   4.2
 16000   1.9  35.4  255  11  5   8.0   4.4 |   1.8  35.2  250   6  3   7.6   4.2
 15500   3.1  37.6  255  10  5   8.1   4.4 |   3.0  37.4  255   5  3   7.6   4.2
 15000   4.3  39.7  255  10  5   8.1   4.5 |   4.1  39.4  265   4  2   7.7   4.2
 14500   5.5  41.9  260  10  5   8.3   4.6 |   5.3  41.5  280   4  2   8.2   4.5
 14000   6.7  44.1  260   9  5   8.4   4.6 |   6.5  43.7  295   4  2   8.2   4.5
 13500   7.9  46.2  265   9  5   7.6   4.2 |   7.7  45.9  315   4  2   7.8   4.3
 13000   9.1  48.4  270   8  4   7.7   4.2 |   8.9  48.0  330   4  2   7.8   4.3
 12500  10.3  50.5  275   8  4   7.8   4.3 |  10.1  50.2  345   4  2   8.7   4.7
 12000  11.4  52.5  285   8  4   7.8   4.3 |  11.4  52.5  350   5  3   8.7   4.8
 11500  12.6  54.7  295   7  4   7.9   4.4 |  12.7  54.9  360   5  3   8.6   4.7
 11000  13.8  56.8  300   7  4   8.1   4.4 |  13.9  57.0  360   6  3   8.9   4.9
 10500  14.8  58.6  305   7  4   4.6   2.5 |  15.0  59.0  005   6  3   3.4   1.9
 10250  15.2  59.4  310   7  4   8.0   4.4 |  15.2  59.4  005   6  3   7.9   4.4
 10000  16.0  60.8  315   7  4  12.2   6.7 |  16.0  60.8  005   6  3  13.1   7.2
  9750  16.8  62.2  315   7  4  10.6   5.8 |  16.8  62.2  005   6  3  11.0   6.1
  9500  17.5  63.5  320   7  4   7.9   4.4 |  17.5  63.5  005   6  3   8.1   4.4
  9250  18.0  64.4  320   7  4   7.3   4.0 |  18.0  64.4  005   6  3   8.0   4.4
  9000  18.7  65.7  325   8  4  10.4   5.7 |  18.8  65.8  005   6  3  11.4   6.3
  8750  19.5  67.1  325   8  4  10.5   5.8 |  19.7  67.5  005   6  3  11.6   6.3
  8500  20.1  68.2  325   9  4   8.6   4.7 |  20.4  68.7  005   6  3  10.1   5.5
  8250  20.7  69.3  325   9  5   7.6   4.2 |  21.2  70.2  005   6  3   9.8   5.4
  8000  21.3  70.3  325  10  5   9.4   5.2 |  21.9  71.4  005   6  3  10.2   5.6
  7750  22.1  71.8  325  10  5   9.8   5.4 |  22.7  72.9  005   6  3  10.3   5.7
  7500  22.7  72.9  320  11  6   7.9   4.3 |  23.4  74.1  005   6  3  10.0   5.5
  7250  23.2  73.8  320  12  6   7.8   4.3 |  24.2  75.6  005   6  3  10.1   5.6
  7000  23.8  74.8  315  14  7   8.0   4.4 |  24.9  76.8  005   6  3   9.7   5.3
  6750  24.3  75.7  315  15  8   5.4   3.0 |  25.6  78.1  005   6  3  10.1   5.5
  6500  24.5  76.1  310  13  7   3.7   2.0 |  26.4  79.5  005   5  3  10.8   5.9
  6250  24.6  76.3  305  11  5   3.8   2.1 |  27.2  81.0  360   5  3  10.3   5.7
  6000  24.8  76.6  295   8  4   5.7   3.1 |  28.0  82.4  360   5  3  11.5   6.3
  5750  25.4  77.7  295   8  4  11.6   6.4 |  29.1  84.4  360   5  3  18.0   9.9
  5500  26.4  79.5  290   7  4  15.1   8.3 |  30.7  87.3  360   5  3  25.6  14.1

           07/21/2016 at 1500 MDT          |       07/21/2016 at 1800 MDT
                                           |
K index... +26.5  LI... -0.7               | K index... +28.5  LI... -0.2
CAPE... +5.6  CIN... -9.7                  | CAPE... +1.1  CIN... -4.2
                                           |
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  240  17  9   2.0   1.1 | -65.0 -85.0  245  17  9   2.8   1.5
 45000 -60.5 -76.9  250  22 11   5.2   2.9 | -59.6 -75.3  260  25 13   4.5   2.5
 40000 -51.5 -60.7  260  19 10   8.5   4.7 | -51.3 -60.3  270  27 14   9.0   4.9
 38000 -46.4 -51.5  265  19 10   8.5   4.7 | -45.9 -50.6  265  23 12   9.0   4.9
 36000 -41.3 -42.3  265  18  9   8.7   4.8 | -40.5 -40.9  260  19 10   8.4   4.6
 34000 -36.1 -33.0  265  16  8   8.7   4.8 | -35.5 -31.9  250  16  8   8.4   4.6
 32000 -30.3 -22.5  260  15  8   8.6   4.7 | -29.9 -21.8  240  15  7   8.4   4.6
 30000 -25.6 -14.1  255  15  7   7.9   4.3 | -25.4 -13.7  230  16  8   7.6   4.1
 29000 -23.3  -9.9  255  14  7   7.9   4.3 | -23.2  -9.8  225  16  8   7.6   4.1
 28000 -21.1  -6.0  250  15  7   6.8   3.7 | -21.0  -5.8  225  17  9   7.2   3.9
 27000 -19.2  -2.6  250  15  8   6.8   3.7 | -18.9  -2.0  225  17  9   7.2   3.9
 26000 -17.2   1.0  245  15  8   6.8   3.7 | -16.8   1.8  225  17  9   7.2   4.0
 25000 -15.2   4.6  245  16  8   6.2   3.4 | -14.8   5.4  225  17  9   5.8   3.2
 24000 -13.4   7.9  240  15  8   6.2   3.4 | -13.1   8.4  220  18  9   5.8   3.2
 23000 -11.6  11.1  240  15  8   6.2   3.4 | -11.4  11.5  220  18  9   5.8   3.2
 22000  -9.8  14.4  240  14  7   6.0   3.3 |  -9.6  14.7  220  18 10   6.0   3.3
 21000  -8.0  17.6  240  13  7   6.0   3.3 |  -7.9  17.8  220  18  9   6.0   3.3
 20000  -6.2  20.8  235  11  6   6.1   3.3 |  -6.1  21.0  220  18  9   6.0   3.3
 19500  -5.4  22.3  235  11  5   6.1   3.3 |  -5.3  22.5  220  18  9   6.2   3.4
 19000  -4.5  23.9  235  10  5   6.1   3.4 |  -4.4  24.1  215  16  8   6.3   3.5
 18500  -3.6  25.5  235   9  4   6.1   3.3 |  -3.4  25.9  215  15  8   6.4   3.5
 18000  -2.6  27.3  235   8  4   6.6   3.6 |  -2.5  27.5  210  13  7   6.0   3.3
 17500  -1.6  29.1  235   7  4   6.7   3.7 |  -1.7  28.9  200  11  6   6.1   3.3
 17000  -0.7  30.7  235   6  3   6.8   3.7 |  -0.8  30.6  185  10  5   6.4   3.5
 16500   0.9  33.6  240   4  2   7.0   3.8 |   0.8  33.4  170   9  4   7.2   3.9
 16000   1.9  35.4  240   3  1   7.2   4.0 |   1.8  35.2  155   8  4   7.5   4.1
 15500   3.0  37.4  235   1  1   7.4   4.1 |   2.9  37.2  145   7  3   7.9   4.3
 15000   4.1  39.4  000   0  0   7.6   4.2 |   4.0  39.2  120   5  3   8.1   4.4
 14500   5.2  41.4  065   1  1   8.4   4.6 |   5.3  41.5  110   5  3   9.2   5.1
 14000   6.5  43.7  060   2  1   8.3   4.6 |   6.6  43.9  100   5  3   9.2   5.0
 13500   7.7  45.9  055   2  1   9.2   5.1 |   7.9  46.2  095   5  3   9.0   4.9
 13000   9.0  48.2  050   3  1   9.2   5.0 |   9.3  48.7  085   5  2   9.0   4.9
 12500  10.4  50.7  040   3  1   9.2   5.0 |  10.6  51.1  080   4  2   9.3   5.1
 12000  11.7  53.1  035   3  1   9.2   5.0 |  12.0  53.6  070   4  2   9.3   5.1
 11500  13.1  55.6  030   3  1   9.5   5.2 |  13.4  56.1  060   4  2   9.2   5.0
 11000  14.5  58.1  025   3  1   9.9   5.4 |  14.8  58.6  040   3  2   9.3   5.1
 10500  15.6  60.1  020   2  1   4.7   2.6 |  15.9  60.6  025   3  2   4.6   2.5
 10250  16.1  61.0  015   2  1   9.2   5.1 |  16.3  61.3  020   3  2   8.0   4.4
 10000  17.0  62.6  015   2  1  13.8   7.6 |  17.2  63.0  005   4  2  12.3   6.7
  9750  18.0  64.4  015   2  1  11.9   6.5 |  18.0  64.4  355   4  2  10.7   5.9
  9500  18.8  65.8  010   2  1   9.1   5.0 |  18.7  65.7  340   5  2   8.1   4.4
  9250  19.4  66.9  010   2  1   8.6   4.7 |  19.3  66.7  335   5  3   7.5   4.1
  9000  20.1  68.2  005   2  1  11.2   6.1 |  20.0  68.0  325   6  3  10.1   5.5
  8750  21.0  69.8  005   2  1  11.0   6.1 |  20.7  69.3  320   7  4  10.3   5.7
  8500  21.8  71.2  360   2  1   9.8   5.4 |  21.5  70.7  320   8  4   9.7   5.3
  8250  22.5  72.5  355   2  1   9.3   5.1 |  22.2  72.0  315   8  4   9.5   5.2
  8000  23.2  73.8  355   3  1  10.2   5.6 |  22.9  73.2  315   9  5   9.6   5.3
  7750  24.0  75.2  350   3  1  10.8   5.9 |  23.6  74.5  315  10  5   9.8   5.4
  7500  24.8  76.6  350   3  1  10.4   5.7 |  24.4  75.9  310  10  5  10.0   5.5
  7250  25.5  77.9  350   3  1  10.5   5.8 |  25.1  77.2  310  11  5  10.2   5.6
  7000  26.3  79.3  350   3  1  10.0   5.5 |  25.9  78.6  310  11  6   9.5   5.2
  6750  27.0  80.6  345   3  1  10.0   5.5 |  26.6  79.9  310  11  6   9.5   5.2
  6500  27.8  82.0  340   3  1  10.7   5.9 |  27.3  81.1  310  11  6  10.3   5.6
  6250  28.6  83.5  340   3  1  10.4   5.7 |  28.1  82.6  310  11  6  10.0   5.5
  6000  29.4  84.9  340   3  1  10.9   6.0 |  28.8  83.8  310  12  6  10.4   5.7
  5750  30.4  86.7  335   3  1  17.7   9.7 |  29.7  85.5  310  11  6  13.2   7.3
  5500  32.1  89.8  335   3  1  27.3  15.0 |  30.8  87.4  310  11  5  16.6   9.1
________________________________________________________________________________

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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