Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 270044
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1844 MDT Tuesday, July 26, 2016

This forecast is for Wednesday, July 27, 2016:

If the trigger temperature of 87.8 F/31.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 880 ft/min (4.5 m/s)
   Maximum height of thermals.................. 14779 ft MSL (9472 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1345 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................. 7341 ft MSL (2034 ft AGL)
Thermal soaring outlook for Thursday 07/28..... Good

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....................... 27999 ft MSL (22692 ft AGL)
Wave soaring outlook for Thursday 07/28........ Poor

Remarks... None

Sunrise/Sunset.................... 05:54:28 / 20:17:46 MDT
Total possible sunshine........... 14 hr 23 min 17 sec (863 min 17 sec)
Altitude of sun at 13:05:55 MDT... 69.18 degrees

Upper air data from numerical model forecast valid on 07/27/2016 at 0600 MDT

Freezing level.................. 16404 ft MSL (11097 ft AGL)
Convective condensation level... 17774 ft MSL (12467 ft AGL)
Lifted condensation level....... 17557 ft MSL (12250 ft AGL)
Lifted index.................... -1.5
K index......................... +20.9

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  -62.8 -81.0   300   26   13   3.5   1.9      M     M       M      M    M
 45000  -56.4 -69.5   295   40   20   5.7   3.1      M     M       M      M    M
 40000  -48.1 -54.6   305   51   26   4.6   2.5      M     M       M      M    M
 38000  -45.3 -49.5   305   47   24   4.6   2.5      M     M       M      M    M
 36000  -42.2 -44.0   310   42   22   4.8   2.6      M     M       M      M    M
 34000  -39.1 -38.4   300   36   18   5.1   2.8      M     M       M      M    M
 32000  -36.0 -32.8   285   31   16   5.6   3.1      M     M       M      M    M
 30000  -31.4 -24.5   285   27   14   7.9   4.3   43.7 110.7     8.3      M    M
 29000  -29.1 -20.4   285   26   13   7.9   4.3   43.1 109.5     7.9      M    M
 28000  -26.7 -16.1   285   24   12   7.8   4.3   42.5 108.4     7.5      M    M
 27000  -24.3 -11.7   290   22   11   7.9   4.3   41.6 106.9     7.0      M    M
 26000  -22.0  -7.6   295   20   10   7.9   4.3   40.9 105.6     6.5      M    M
 25000  -19.6  -3.3   305   19   10   7.6   4.2   40.3 104.6     6.1      M    M
 24000  -17.5   0.5   305   16    8   7.1   3.9   39.3 102.7     5.3      M    M
 23000  -15.4   4.3   300   14    7   7.2   3.9   38.3 100.9     4.5      M    M
 22000  -13.3   8.1   300   12    6   6.9   3.8   37.5  99.5     3.8      M    M
 21000  -11.4  11.5   300   10    5   6.7   3.7   36.3  97.3     2.7      M    M
 20000   -9.5  14.9   300    9    5   6.8   3.7   35.2  95.3     1.7      M    M
 19500   -8.5  16.7   300    9    4   6.9   3.8   34.7  94.5     1.2      M    M
 19000   -7.4  18.7   305    8    4   9.3   5.1   34.5  94.0     0.9      M    M
 18500   -5.3  22.5   310    8    4   9.1   5.0   34.3  93.7     0.8      M    M
 18000   -4.0  24.8   310    8    4   8.7   4.8   34.1  93.4     0.6      M    M
 17500   -2.7  27.1   310    8    4   8.7   4.8   34.0  93.1     0.4      M    M
 17000   -1.4  29.5   315    7    4   9.2   5.1   33.8  92.8     0.3      M    M
 16500   -0.0  32.0   315    7    4   9.5   5.2   33.8  92.8     0.2      M    M
 16000    1.4  34.5   315    6    3   9.5   5.2   33.7  92.7     0.2      M    M
 15500    2.8  37.0   315    6    3   9.1   5.0   33.6  92.5     0.1      M    M
 15000    4.2  39.6   315    7    3   9.0   5.0   33.5  92.3     0.0      M    M
 14500    5.5  41.9   315    7    4   9.5   5.2   33.4  92.2    -0.1    840  4.3
 14000    6.9  44.4   315    7    4   9.5   5.2   33.4  92.1    -0.1    783  4.0
 13500    8.3  46.9   315    7    4   9.3   5.1   33.3  92.0    -0.2    726  3.7
 13000    9.7  49.5   315    8    4   9.2   5.1   33.2  91.8    -0.3    670  3.4
 12500   11.1  52.0   315    8    4   9.0   4.9   33.2  91.7    -0.3    614  3.1
 12000   12.4  54.3   310    8    4   8.8   4.8   33.0  91.4    -0.5    560  2.8
 11500   13.7  56.7   310    9    5   8.6   4.7   32.9  91.2    -0.7    507  2.6
 11000   14.9  58.8   305    9    5   8.1   4.5   32.6  90.8    -0.9    454  2.3
 10500   16.2  61.2   300    9    4   4.7   2.6   32.4  90.4    -1.1    402  2.0
 10250   16.4  61.5   300    9    4   5.9   3.2   31.9  89.4    -1.6    388  2.0
 10000   17.2  63.0   300    9    5  11.3   6.2   31.9  89.5    -1.6    358  1.8
  9750   17.9  64.2   295    9    5  10.3   5.7   32.0  89.6    -1.6    328  1.7
  9500   18.7  65.7   295    9    5   9.0   4.9   32.0  89.6    -1.6    298  1.5
  9250   19.2  66.6   290    9    5   7.3   4.0   31.8  89.3    -1.7    274  1.4
  9000   19.8  67.6   290    9    5   8.5   4.7   31.7  89.1    -1.9    249  1.3
  8750   20.5  68.9   285    9    5   9.2   5.0   31.6  89.0    -2.0    222  1.1
  8500   21.1  70.0   285   10    5   8.2   4.5   31.6  88.8    -2.1    195  1.0
  8250   21.7  71.1   285   10    5   7.2   3.9   31.4  88.5    -2.3    172  0.9
  8000   22.2  72.0   280   10    5   7.7   4.2   31.2  88.2    -2.4    148  0.8
  7750   22.8  73.0   280   10    5   8.1   4.4   31.1  88.0    -2.6    123  0.6
  7500   23.3  73.9   280   10    5   7.1   3.9   30.9  87.7    -2.8     99  0.5
  7250   23.8  74.8   280   11    6   6.2   3.4   30.7  87.2    -3.1     78  0.4
  7000   24.3  75.7   285   11    6   7.2   4.0   30.4  86.8    -3.3     56  0.3
  6750   24.7  76.5   285   12    6   3.9   2.2   30.2  86.3    -3.6     35  0.2
  6500   24.7  76.5   280   12    6  -3.6  -2.0   29.4  85.0    -4.4     28  0.1
  6250   24.2  75.6   275   11    6  -8.1  -4.4   28.2  82.8    -5.6     37  0.2
  6000   23.6  74.5   270   11    6  -0.7  -0.4   27.0  80.7    -6.9     45  0.2
  5750   23.6  74.5   265   12    6  -8.9  -4.9   26.3  79.3    -7.7     41  0.2
  5500   21.5  70.7   255    9    5 -42.9 -23.5   23.6  74.5   -10.6     95  0.5

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

           07/27/2016 at 0900 MDT          |       07/27/2016 at 1200 MDT
                                           |
K index... +18.4  LI... -0.7               | K index... +14.8  LI... -3.4
CAPE... +20.9  CIN... -271.5               | CAPE... +446.5  CIN... -60.2
                                           |
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 -62.6 -80.7  310  28 14   3.3   1.8 | -62.4 -80.3  310  26 13   3.9   2.1
 45000 -56.9 -70.4  305  42 21   4.8   2.6 | -56.2 -69.2  310  41 21   4.6   2.5
 40000 -49.2 -56.6  310  52 27   5.3   2.9 | -48.9 -56.0  315  54 28   5.1   2.8
 38000 -46.1 -51.0  315  52 27   5.3   2.9 | -45.8 -50.4  320  55 29   5.1   2.8
 36000 -42.9 -45.2  320  51 26   5.6   3.1 | -42.8 -45.0  320  57 29   5.5   3.0
 34000 -38.8 -37.8  320  47 24   6.9   3.8 | -38.7 -37.7  320  51 26   6.9   3.8
 32000 -34.7 -30.5  320  43 22   6.9   3.8 | -34.6 -30.3  320  45 23   6.9   3.8
 30000 -30.7 -23.3  320  36 19   6.5   3.6 | -30.7 -23.3  320  39 20   6.5   3.6
 29000 -28.3 -18.9  315  32 16   6.5   3.6 | -28.2 -18.8  320  35 18   6.5   3.6
 28000 -26.2 -15.2  315  28 15   7.4   4.0 | -26.2 -15.2  320  33 17   7.7   4.2
 27000 -24.1 -11.4  310  26 13   7.3   4.0 | -23.9 -11.0  320  32 16   7.6   4.1
 26000 -21.9  -7.4  305  23 12   7.3   4.0 | -21.7  -7.1  325  31 16   7.6   4.1
 25000 -19.7  -3.5  300  20 10   7.3   4.0 | -19.4  -2.9  325  29 15   7.2   4.0
 24000 -17.5   0.5  295  18  9   7.3   4.0 | -17.3   0.9  320  25 13   7.0   3.8
 23000 -15.4   4.3  295  16  8   7.3   4.0 | -15.2   4.6  310  20 11   7.0   3.8
 22000 -13.2   8.2  290  13  7   6.5   3.5 | -13.2   8.2  295  17  9   6.1   3.3
 21000 -11.5  11.3  285  11  6   6.2   3.4 | -11.5  11.3  290  15  8   5.8   3.2
 20000  -9.7  14.5  280   9  5   6.4   3.5 |  -9.8  14.4  285  12  6   6.0   3.3
 19500  -8.8  16.2  275   8  4   7.1   3.9 |  -9.0  15.8  280  11  6   6.9   3.8
 19000  -7.6  18.3  280   7  4   9.6   5.3 |  -7.7  18.1  280  11  5  10.0   5.5
 18500  -6.2  20.8  285   6  3   9.6   5.2 |  -6.2  20.8  280  10  5   9.9   5.5
 18000  -4.8  23.4  295   6  3   9.1   5.0 |  -4.8  23.4  280  10  5   9.3   5.1
 17500  -3.5  25.7  305   6  3   9.0   4.9 |  -3.5  25.7  290  10  5   9.1   5.0
 17000  -2.1  28.2  315   6  3   9.1   5.0 |  -2.1  28.2  295  10  5   9.1   5.0
 16500  -0.8  30.6  320   6  3   9.5   5.2 |  -0.7  30.7  300   9  5   9.3   5.1
 16000   0.7  33.3  320   6  3   9.5   5.2 |   0.6  33.1  305   9  5   9.3   5.1
 15500   2.0  35.6  325   6  3   9.2   5.0 |   2.7  36.9  310  10  5   9.5   5.2
 15000   4.1  39.4  330   7  4   9.2   5.0 |   4.1  39.4  315  10  5   9.5   5.2
 14500   5.5  41.9  330   7  4   9.4   5.2 |   5.5  41.9  315  10  5   9.4   5.1
 14000   6.9  44.4  330   8  4   9.4   5.2 |   6.9  44.4  320  10  5   9.4   5.2
 13500   8.2  46.8  330   9  4   9.4   5.1 |   8.3  46.9  320  10  5   9.2   5.1
 13000   9.6  49.3  330   9  5   9.4   5.1 |   9.6  49.3  320  10  5   9.2   5.1
 12500  11.0  51.8  330  10  5   9.4   5.2 |  11.0  51.8  325  11  5   9.1   5.0
 12000  12.4  54.3  335  10  5   9.4   5.2 |  12.3  54.1  325  11  5   9.0   5.0
 11500  13.8  56.8  335  11  6   9.1   5.0 |  13.7  56.7  325  11  6   9.1   5.0
 11000  15.1  59.2  330  11  6   8.6   4.7 |  15.0  59.0  330  11  5   9.0   4.9
 10500  16.4  61.5  330  11  6   3.9   2.1 |  16.3  61.3  330  11  5   4.3   2.4
 10250  16.6  61.9  330  11  6   5.2   2.9 |  16.5  61.7  335  11  5   6.0   3.3
 10000  17.4  63.3  330  12  6  12.0   6.6 |  17.3  63.1  335  11  5  11.5   6.3
  9750  18.2  64.8  325  12  6  11.0   6.0 |  18.0  64.4  340  11  5  10.4   5.7
  9500  19.0  66.2  325  12  6   8.3   4.5 |  18.8  65.8  340  11  6   8.2   4.5
  9250  19.4  66.9  325  12  6   5.8   3.2 |  19.3  66.7  340  11  5   6.7   3.7
  9000  19.9  67.8  325  12  6   8.2   4.5 |  19.9  67.8  345  11  5   8.9   4.9
  8750  20.6  69.1  325  12  6   8.6   4.7 |  20.5  68.9  345  11  6   9.2   5.1
  8500  21.2  70.2  325  13  6   7.9   4.3 |  21.2  70.2  350  11  6   6.8   3.7
  8250  21.7  71.1  325  13  7   7.7   4.2 |  21.5  70.7  350  10  5   5.2   2.9
  8000  22.3  72.1  325  13  7   6.9   3.8 |  21.9  71.4  355  10  5   5.4   3.0
  7750  22.7  72.9  325  14  7   5.5   3.0 |  22.2  72.0  360   9  5   5.9   3.2
  7500  23.1  73.6  325  14  7   4.1   2.2 |  22.6  72.7  010   8  4   8.2   4.5
  7250  23.3  73.9  330  15  8   3.0   1.6 |  23.2  73.8  015   8  4   9.4   5.2
  7000  23.5  74.3  330  16  8   3.5   1.9 |  23.8  74.8  025   7  4   8.9   4.9
  6750  23.7  74.7  330  17  9   2.5   1.3 |  24.4  75.9  035   7  4   9.8   5.4
  6500  23.7  74.7  330  16  8   0.3   0.2 |  25.1  77.2  035   7  4  11.0   6.0
  6250  23.6  74.5  335  14  7   1.3   0.7 |  26.0  78.8  035   7  4  11.7   6.4
  6000  23.6  74.5  340  12  6  -3.1  -1.7 |  26.8  80.2  035   7  3   9.5   5.2
  5750  23.2  73.8  345   9  5   4.1   2.3 |  27.6  81.7  035   7  3  15.2   8.3
  5500  24.5  76.1  345   8  4  29.3  16.1 |  29.3  84.7  035   7  4  30.5  16.7

           07/27/2016 at 1500 MDT          |       07/27/2016 at 1800 MDT
                                           |
K index... +23.4  LI... -3.2               | K index... +30.3  LI... -3.9
CAPE... +626.5  CIN... -20.2               | CAPE... +972.9  CIN... -12.1
                                           |
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 -62.6 -80.7  300  22 11   3.6   2.0 | -62.9 -81.2  280  20 11   3.1   1.7
 45000 -56.1 -69.0  305  38 19   4.9   2.7 | -56.7 -70.1  300  37 19   5.3   2.9
 40000 -48.7 -55.7  315  51 26   5.3   2.9 | -48.7 -55.7  320  55 28   5.2   2.9
 38000 -45.6 -50.1  320  53 27   5.3   2.9 | -45.6 -50.1  320  53 27   5.2   2.9
 36000 -42.4 -44.3  320  55 28   5.8   3.2 | -42.4 -44.3  325  52 27   5.9   3.2
 34000 -38.4 -37.1  320  51 26   6.8   3.7 | -38.3 -36.9  325  47 24   6.9   3.8
 32000 -34.3 -29.7  320  46 24   6.6   3.6 | -34.2 -29.6  330  43 22   7.3   4.0
 30000 -29.5 -21.1  320  40 20   7.2   4.0 | -29.1 -20.4  330  37 19   7.6   4.2
 29000 -27.3 -17.1  320  37 19   7.2   4.0 | -26.9 -16.4  330  35 18   7.6   4.2
 28000 -25.2 -13.4  320  34 18   6.4   3.5 | -24.7 -12.5  330  33 17   6.9   3.8
 27000 -23.3  -9.9  320  33 17   6.5   3.6 | -22.6  -8.7  330  31 16   6.9   3.8
 26000 -21.4  -6.5  320  31 16   6.5   3.6 | -20.6  -5.1  325  29 15   6.9   3.8
 25000 -19.4  -2.9  320  30 15   7.7   4.2 | -18.5  -1.3  325  28 14   7.2   3.9
 24000 -16.9   1.6  320  28 14   8.3   4.6 | -16.3   2.7  315  27 14   7.3   4.0
 23000 -14.4   6.1  320  27 14   8.3   4.6 | -14.1   6.6  310  26 13   7.3   4.0
 22000 -12.0  10.4  315  25 13   6.6   3.6 | -12.0  10.4  305  26 13   7.0   3.8
 21000 -10.2  13.6  310  23 12   6.0   3.3 |  -9.9  14.2  300  25 13   6.9   3.8
 20000  -8.4  16.9  300  22 11   6.1   3.3 |  -7.9  17.8  295  24 12   7.0   3.8
 19500  -7.5  18.5  295  21 11   6.5   3.6 |  -6.9  19.6  290  24 12   7.4   4.1
 19000  -6.4  20.5  295  21 11   8.3   4.5 |  -5.7  21.7  290  23 12   8.8   4.8
 18500  -5.2  22.6  295  20 10   8.2   4.5 |  -4.4  24.1  285  23 12   8.8   4.8
 18000  -4.0  24.8  300  19 10   9.0   4.9 |  -3.1  26.4  285  22 11   8.5   4.7
 17500  -2.7  27.1  300  19 10   9.2   5.1 |  -2.0  28.4  285  21 11   8.5   4.7
 17000  -1.3  29.7  300  18  9   9.2   5.1 |  -0.8  30.6  285  20 10   8.5   4.7
 16500  -0.0  32.0  305  17  9   9.0   4.9 |   0.4  32.7  290  17  9   8.2   4.5
 16000   1.3  34.3  305  16  8   9.1   5.0 |   1.6  34.9  290  15  8   8.3   4.5
 15500   3.2  37.8  310  15  8   8.8   4.8 |   3.3  37.9  295  11  6   8.0   4.4
 15000   4.5  40.1  310  14  7   8.8   4.8 |   4.5  40.1  300   9  5   8.0   4.4
 14500   5.8  42.4  310  13  6   8.8   4.8 |   5.6  42.1  315   6  3   7.4   4.1
 14000   7.1  44.8  315  11  6   8.8   4.8 |   6.7  44.1  340   5  3   7.4   4.1
 13500   8.4  47.1  315  10  5   8.5   4.7 |   7.8  46.0  010   6  3   8.5   4.7
 13000   9.6  49.3  320   9  5   8.5   4.7 |   8.9  48.0  020   7  4   8.6   4.7
 12500  10.9  51.6  325   8  4   8.6   4.7 |  10.1  50.2  025   8  4   9.0   4.9
 12000  12.2  54.0  330   7  4   8.7   4.8 |  11.5  52.7  025   9  4   9.1   5.0
 11500  13.5  56.3  340   6  3   8.5   4.7 |  12.8  55.0  025   9  5   9.6   5.3
 11000  14.5  58.1  005   6  3   8.5   4.7 |  14.2  57.6  025   9  5   9.7   5.3
 10500  15.6  60.1  025   6  3   4.9   2.7 |  15.5  59.9  025   9  5   4.8   2.6
 10250  15.9  60.6  030   6  3   7.6   4.2 |  15.7  60.3  025   9  5   6.9   3.8
 10000  16.7  62.1  030   6  3  13.0   7.1 |  16.6  61.9  025  10  5  13.3   7.3
  9750  17.6  63.7  035   6  3  12.1   6.6 |  17.5  63.5  020  10  5  12.1   6.7
  9500  18.4  65.1  035   7  3   9.3   5.1 |  18.4  65.1  020  10  5   9.3   5.1
  9250  18.9  66.0  035   7  3   8.0   4.4 |  18.9  66.0  020  10  5   7.9   4.4
  9000  19.7  67.5  035   7  3  11.0   6.1 |  19.7  67.5  020  10  5  11.0   6.0
  8750  20.5  68.9  035   7  3  11.2   6.1 |  20.5  68.9  020  10  5  11.1   6.1
  8500  21.3  70.3  035   7  4  10.3   5.7 |  21.3  70.3  020  10  5  10.3   5.7
  8250  22.0  71.6  035   7  4   9.5   5.2 |  22.1  71.8  020  10  5   9.6   5.3
  8000  22.8  73.0  035   7  4  10.5   5.7 |  22.8  73.0  020  10  5  10.1   5.6
  7750  23.6  74.5  035   7  4  11.0   6.1 |  23.5  74.3  015  10  5  10.3   5.7
  7500  24.3  75.7  035   7  4  10.3   5.6 |  24.3  75.7  015  10  5  10.0   5.5
  7250  25.1  77.2  035   7  4  10.3   5.6 |  25.0  77.0  015  11  5   9.9   5.4
  7000  25.8  78.4  035   7  4   9.5   5.2 |  25.8  78.4  015  11  5   9.9   5.4
  6750  26.5  79.7  035   7  4   9.3   5.1 |  26.5  79.7  015  11  6  10.2   5.6
  6500  27.3  81.1  035   7  4  10.6   5.8 |  27.3  81.1  015  11  6  10.6   5.8
  6250  28.1  82.6  035   7  3  11.5   6.3 |  28.1  82.6  015  11  5  11.1   6.1
  6000  28.9  84.0  030   7  3   9.6   5.3 |  28.9  84.0  015  11  5   9.3   5.1
  5750  29.7  85.5  030   7  3  15.9   8.7 |  29.6  85.3  015  11  5  12.5   6.8
  5500  31.5  88.7  030   7  3  31.0  17.0 |  30.9  87.6  010  10  5  23.0  12.6
________________________________________________________________________________

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.

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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