Soaring Guidance
Issued by NWS Denver/Boulder, CO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24

000
UXUS97 KBOU 151326
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0726 MDT Friday, August 15, 2014

This forecast is for Friday, August 15, 2014:

If the trigger temperature of 80.6 F/27.0 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1139 ft/min (5.8 m/s)
   Maximum height of thermals.................. 15933 ft MSL (10648 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 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................. 11963 ft MSL (6677 ft AGL)
Thermal soaring outlook for Saturday 08/16..... 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)................ Neither
Potential height of wave....................... 17084 ft MSL (11799 ft AGL)
Wave soaring outlook for Saturday 08/16........ Poor

Remarks...

Sunrise/Sunset.................... 06:11:33 / 19:56:47 MDT
Total possible sunshine........... 13 hr 45 min 14 sec (825 min 14 sec)
Altitude of sun at 13:03:49 MDT... 64.11 degrees

Upper air data from rawinsonde observation taken on 08/15/2014 at 0600 MDT

Freezing level.................. 15771 ft MSL (10486 ft AGL)
Convective condensation level... 15322 ft MSL (10037 ft AGL)
Lifted condensation level....... 15761 ft MSL (10475 ft AGL)
Lifted index.................... -0.7
K index......................... +26.2

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  -66.5 -87.7   280   20   10   3.1   1.7   81.5 178.7    29.1      M    M
 45000  -60.8 -77.4   225   33   17   8.7   4.8   66.5 151.8    21.8      M    M
 40000  -52.7 -62.9   255   47   24   8.0   4.4   55.3 131.5    15.9      M    M
 38000  -48.0 -54.4   250   55   28   7.2   3.9   53.6 128.6    15.2      M    M
 36000  -43.1 -45.6   245   52   27   9.9   5.4   52.4 126.4    14.7      M    M
 34000  -37.9 -36.2   245   43   22   7.9   4.3   51.4 124.4    14.3      M    M
 32000  -33.5 -28.3   240   26   13   7.4   4.1   49.6 121.2    13.3      M    M
 30000  -29.1 -20.4   240   21   11   7.3   4.0   47.6 117.7    12.1      M    M
 29000  -26.4 -15.5   245   20   10   7.3   4.0   46.3 115.3    11.3      M    M
 28000  -24.3 -11.7   255   19   10   7.3   4.0   45.3 113.6    10.7      M    M
 27000  -22.0  -7.6   260   19   10   8.7   4.8   44.6 112.3    10.2      M    M
 26000  -19.5  -3.1   270   19   10   7.6   4.2   44.0 111.3     9.9      M    M
 25000  -17.2   1.0   275   19   10   7.9   4.3   43.3 109.9     9.4      M    M
 24000  -14.8   5.4   280   18    9   6.8   3.7   42.7 108.9     9.0      M    M
 23000  -12.8   9.0   285   17    9   5.4   2.9   41.6 106.8     8.1      M    M
 22000  -11.7  10.9   290   16    8   7.1   3.9   39.6 103.3     6.4      M    M
 21000  -10.2  13.6   285   13    7   5.4   3.0   37.8 100.1     5.0      M    M
 20000   -8.2  17.2   280   11    6   9.0   4.9   36.9  98.3     4.2      M    M
 19500   -6.6  20.1   290   13    7   7.4   4.0   37.0  98.6     4.3      M    M
 19000   -5.9  21.4   310   12    6   6.1   3.3   36.3  97.3     3.6      M    M
 18500   -5.3  22.5   315   13    7   4.5   2.5   35.4  95.8     2.8      M    M
 18000   -4.3  24.3   320   14    7   8.4   4.6   34.8  94.7     2.2      M    M
 17500   -3.1  26.4   320   15    8   8.4   4.6   34.6  94.2     2.1      M    M
 17000   -2.2  28.0   320   16    8   5.3   2.9   34.1  93.3     1.5      M    M
 16500   -1.4  29.5   325   16    8   5.5   3.0   33.3  92.0     0.9      M    M
 16000   -0.5  31.1   335   16    8   5.7   3.1   32.6  90.7     0.2      M    M
 15500    0.3  32.5   340   15    8   6.1   3.4   32.0  89.6    -0.4    913  4.6
 15000    1.1  34.0   355   15    8   6.8   3.7   31.4  88.5    -1.1    875  4.4
 14500    2.8  37.0   350   15    8   8.2   4.5   31.0  87.7    -1.6    800  4.1
 14000    4.0  39.2   350   15    8   8.2   4.5   30.7  87.3    -1.8    749  3.8
 13500    5.2  41.4   350   16    8   8.2   4.5   30.4  86.8    -2.1    698  3.5
 13000    6.5  43.7   345   17    9   8.3   4.5   30.2  86.3    -2.3    647  3.3
 12500    7.6  45.7   345   18    9   7.5   4.1   29.9  85.8    -2.6    596  3.0
 12000    8.7  47.7   345   19   10   7.4   4.1   29.5  85.2    -3.0    551  2.8
 11500    9.7  49.5   340   17    9   7.6   4.2   29.1  84.5    -3.5    505  2.6
 11000   10.9  51.6   330   15    8   8.7   4.8   28.9  84.0    -3.7    453  2.3
 10500   12.2  54.0   320   13    7   8.5   4.7   28.7  83.7    -3.9    400  2.0
 10250   12.8  55.0   320   13    7   8.3   4.5   28.6  83.5    -4.0    374  1.9
 10000   13.4  56.1   315   12    6   8.2   4.5   28.5  83.3    -4.2    348  1.8
  9750   14.1  57.4   315   12    6   8.2   4.5   28.4  83.1    -4.3    323  1.6
  9500   14.7  58.5   315   12    6   8.2   4.5   28.3  82.9    -4.4    297  1.5
  9250   15.3  59.5   310   11    6   8.2   4.5   28.2  82.7    -4.5    272  1.4
  9000   15.9  60.6   310   11    6   8.2   4.5   28.1  82.5    -4.6    246  1.2
  8750   16.5  61.7   310   12    6   8.2   4.5   28.0  82.3    -4.8    220  1.1
  8500   17.1  62.8   310   12    6   8.3   4.5   27.8  82.1    -4.9    195  1.0
  8250   17.7  63.9   310   13    6   8.2   4.5   27.7  81.9    -5.0    169  0.9
  8000   18.3  64.9   310   13    7   8.3   4.5   27.6  81.7    -5.2    144  0.7
  7750   18.9  66.0   310   13    7   8.2   4.5   27.5  81.5    -5.3    118  0.6
  7500   19.5  67.1   310   13    7   8.4   4.6   27.4  81.3    -5.5     93  0.5
  7250   20.1  68.2   310   13    7   7.5   4.1   27.3  81.1    -5.6     67  0.3
  7000   20.6  69.1   310   13    7   5.3   2.9   27.0  80.6    -5.9     46  0.2
  6750   20.9  69.6   305   12    6   4.7   2.6   26.6  79.9    -6.3     28  0.1
  6500   21.3  70.3   300   11    6   4.8   2.6   26.2  79.2    -6.7     11  0.1
  6250   21.6  70.9   295   11    5   4.9   2.7   25.9  78.6    -7.1      M    M
  6000   21.9  71.4   285   10    5   4.4   2.4   25.5  77.9    -7.5      M    M
  5750   21.8  71.2   280    7    4 -12.1  -6.6   24.7  76.4    -8.4      M    M
  5500   19.6  67.3   265    4    2 -42.4 -23.3   21.9  71.4   -11.3     31  0.2

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

           08/15/2014 at 0900 MDT          |       08/15/2014 at 1200 MDT
                                           |
K index... +23.5  LI... -2.1               | K index... +22.2  LI... -1.8
CAPE... +259.8  CIN... -79.6               | CAPE... +411.0  CIN... -7.1
                                           |
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 -64.0 -83.2  245  21 11   1.8   1.0 | -63.8 -82.8  255  21 11   1.4   0.8
 45000 -60.2 -76.4  250  28 14   4.3   2.4 | -60.4 -76.7  255  26 14   4.4   2.4
 40000 -52.7 -62.9  265  28 14   7.5   4.1 | -52.9 -63.2  265  16  8   7.1   3.9
 38000 -48.3 -54.9  265  30 16   7.5   4.1 | -48.6 -55.5  275  15  8   7.1   3.9
 36000 -43.8 -46.8  260  33 17   7.6   4.2 | -44.4 -47.9  285  14  7   7.2   4.0
 34000 -39.0 -38.2  265  26 13   8.0   4.4 | -39.6 -39.3  285  13  7   8.1   4.4
 32000 -34.3 -29.7  275  18  9   7.9   4.3 | -34.7 -30.5  280  13  7   7.9   4.4
 30000 -29.5 -21.1  280  16  8   7.9   4.4 | -29.9 -21.8  285  13  7   8.2   4.5
 29000 -27.2 -17.0  285  16  8   7.9   4.4 | -27.5 -17.5  290  13  7   8.2   4.5
 28000 -24.8 -12.6  290  16  8   7.8   4.3 | -24.5 -12.1  295  14  7   7.3   4.0
 27000 -22.0  -7.6  290  17  9   7.6   4.2 | -22.3  -8.1  295  14  7   7.4   4.1
 26000 -19.7  -3.5  295  17  9   7.6   4.2 | -20.1  -4.2  300  14  7   7.4   4.1
 25000 -17.4   0.7  295  18  9   7.1   3.9 | -17.9  -0.2  300  14  7   7.1   3.9
 24000 -15.5   4.1  295  18  9   6.5   3.6 | -15.9   3.4  305  16  8   6.6   3.6
 23000 -13.7   7.3  295  18  9   6.5   3.6 | -13.9   7.0  310  17  9   6.6   3.6
 22000 -11.8  10.8  300  17  9   6.1   3.4 | -12.0  10.4  310  18  9   6.5   3.6
 21000 -10.1  13.8  300  17  9   5.6   3.1 | -10.1  13.8  315  20 10   6.3   3.5
 20000  -8.5  16.7  305  17  9   5.6   3.1 |  -8.1  17.4  315  21 11   6.3   3.5
 19500  -7.7  18.1  310  17  9   5.5   3.0 |  -7.2  19.0  315  22 11   6.3   3.5
 19000  -6.8  19.8  310  17  9   6.6   3.6 |  -6.3  20.7  315  22 11   5.9   3.2
 18500  -5.8  21.6  310  16  8   6.5   3.6 |  -5.4  22.3  315  22 11   5.9   3.3
 18000  -4.8  23.4  315  16  8   5.9   3.2 |  -4.5  23.9  315  22 11   5.8   3.2
 17500  -4.0  24.8  315  15  8   5.3   2.9 |  -3.7  25.3  310  21 11   5.8   3.2
 17000  -3.2  26.2  315  14  7   5.3   2.9 |  -2.9  26.8  310  20 10   5.8   3.2
 16500  -2.5  27.5  315  14  7   5.6   3.1 |  -2.1  28.2  305  18 10   4.7   2.6
 16000  -1.7  28.9  320  13  7   5.7   3.1 |  -1.5  29.3  305  17  9   4.8   2.7
 15500  -0.9  30.4  325  13  7   6.7   3.7 |  -0.8  30.6  305  16  8   6.1   3.4
 15000   0.2  32.4  330  14  7   7.0   3.9 |   0.1  32.2  310  15  8   6.5   3.6
 14500   1.2  34.2  335  15  8   7.4   4.1 |   1.5  34.7  315  14  7   8.5   4.7
 14000   2.8  37.0  345  17  9   8.0   4.4 |   2.8  37.0  320  13  7   8.4   4.6
 13500   3.9  39.0  345  19 10   8.8   4.8 |   4.0  39.2  325  13  7   9.1   5.0
 13000   5.2  41.4  350  20 10   9.1   5.0 |   5.4  41.7  330  15  8   9.3   5.1
 12500   6.4  43.5  350  20 10   9.2   5.0 |   6.9  44.4  335  16  8   9.4   5.2
 12000   7.8  46.0  350  21 11   9.2   5.0 |   8.3  46.9  335  16  8   9.5   5.2
 11500   9.1  48.4  355  21 11   9.2   5.0 |   9.6  49.3  340  17  8   9.5   5.2
 11000  10.5  50.9  355  21 11   8.9   4.9 |  11.0  51.8  340  17  9   9.1   5.0
 10500  11.9  53.4  355  21 11   4.0   2.2 |  12.4  54.3  335  17  9   4.3   2.4
 10250  12.0  53.6  355  21 11   4.5   2.5 |  12.5  54.5  335  17  9   5.4   3.0
 10000  12.7  54.9  350  19 10  11.3   6.2 |  13.3  55.9  335  17  9  12.6   6.9
  9750  13.5  56.3  350  18  9  10.1   5.5 |  14.1  57.4  335  16  8  11.3   6.2
  9500  14.2  57.6  350  17  9   8.2   4.5 |  14.8  58.6  335  16  8   8.8   4.8
  9250  14.7  58.5  345  15  8   6.1   3.4 |  15.3  59.5  335  14  7   6.7   3.7
  9000  15.2  59.4  345  14  7   8.5   4.7 |  15.8  60.4  330  13  7   9.3   5.1
  8750  15.9  60.6  345  13  6   9.1   5.0 |  16.5  61.7  330  11  6   9.8   5.4
  8500  16.6  61.9  340  11  6   8.9   4.9 |  17.1  62.8  325  10  5   9.8   5.4
  8250  17.2  63.0  335  11  6   8.8   4.8 |  17.8  64.0  320   9  5   9.6   5.3
  8000  17.9  64.2  335  11  6   9.3   5.1 |  18.5  65.3  320   8  4  10.4   5.7
  7750  18.5  65.3  330  12  6   9.4   5.2 |  19.3  66.7  315   8  4  10.9   6.0
  7500  19.2  66.6  330  13  7   7.9   4.3 |  20.1  68.2  315   7  4  10.0   5.5
  7250  19.7  67.5  325  14  7   7.2   3.9 |  20.8  69.4  315   7  4  10.0   5.5
  7000  20.2  68.4  320  16  8   7.2   3.9 |  21.5  70.7  315   7  4   9.4   5.2
  6750  20.6  69.1  315  18  9   4.8   2.7 |  22.2  72.0  315   7  4   9.8   5.4
  6500  20.8  69.4  315  16  8   2.5   1.4 |  23.0  73.4  315   7  4  11.0   6.0
  6250  20.9  69.6  310  13  7   3.5   1.9 |  23.8  74.8  315   7  3  11.6   6.3
  6000  21.0  69.8  305  10  5   0.1   0.0 |  24.7  76.5  315   6  3   9.5   5.2
  5750  20.9  69.6  295   6  3   4.5   2.5 |  25.4  77.7  315   6  3  14.3   7.9
  5500  21.8  71.2  285   5  2  22.2  12.2 |  27.0  80.6  315   6  3  28.0  15.4

           08/15/2014 at 1500 MDT          |       08/15/2014 at 1800 MDT
                                           |
K index... +24.3  LI... -1.2               | K index... +30.6  LI... -3.0
CAPE... +228.7  CIN... -31.0               | CAPE... +601.9  CIN... -34.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.2 -83.6  255  19 10   1.5   0.8 | -64.6 -84.3  255  20 10   1.4   0.8
 45000 -60.6 -77.1  260  25 13   4.5   2.5 | -61.0 -77.8  265  24 12   4.7   2.6
 40000 -52.8 -63.0  275  14  7   7.3   4.0 | -52.9 -63.2  290  16  8   7.8   4.3
 38000 -48.5 -55.3  285  13  7   7.3   4.0 | -48.2 -54.8  290  17  9   7.8   4.3
 36000 -44.1 -47.4  295  12  6   7.5   4.1 | -43.5 -46.3  290  18  9   7.8   4.3
 34000 -39.3 -38.7  290  14  7   8.1   4.4 | -38.8 -37.8  285  20 10   7.9   4.3
 32000 -34.4 -29.9  280  16  8   8.0   4.4 | -34.1 -29.4  280  22 11   7.8   4.3
 30000 -29.6 -21.3  275  15  8   8.1   4.4 | -29.4 -20.9  280  22 11   7.9   4.4
 29000 -26.6 -15.9  275  14  7   8.1   4.4 | -27.0 -16.6  280  21 11   7.9   4.4
 28000 -24.2 -11.6  275  14  7   7.4   4.0 | -24.1 -11.4  280  21 11   7.1   3.9
 27000 -22.0  -7.6  275  15  8   7.4   4.1 | -21.9  -7.4  285  20 10   7.2   4.0
 26000 -19.8  -3.6  275  16  8   7.4   4.1 | -19.8  -3.6  285  19 10   7.2   4.0
 25000 -17.6   0.3  280  17  9   7.1   3.9 | -17.7   0.1  290  19 10   6.9   3.8
 24000 -15.5   4.1  285  18  9   6.8   3.7 | -15.7   3.7  295  20 10   6.5   3.6
 23000 -13.5   7.7  290  20 10   6.8   3.7 | -13.8   7.2  300  21 11   6.5   3.6
 22000 -11.5  11.3  295  22 11   6.5   3.6 | -11.9  10.6  305  23 12   6.2   3.4
 21000  -9.6  14.7  300  24 12   6.3   3.4 | -10.1  13.8  305  23 12   6.0   3.3
 20000  -7.7  18.1  300  25 13   6.3   3.4 |  -8.3  17.1  300  24 13   6.0   3.3
 19500  -6.7  19.9  305  26 13   6.3   3.4 |  -7.4  18.7  300  25 13   6.0   3.3
 19000  -5.8  21.6  305  27 14   5.8   3.2 |  -6.5  20.3  300  25 13   6.8   3.7
 18500  -5.0  23.0  300  27 14   5.9   3.2 |  -5.5  22.1  300  26 13   6.8   3.7
 18000  -4.2  24.4  300  27 14   6.2   3.4 |  -4.5  23.9  300  26 13   7.1   3.9
 17500  -3.2  26.2  300  27 14   6.4   3.5 |  -3.5  25.7  300  26 13   7.4   4.1
 17000  -2.3  27.9  300  27 14   6.6   3.6 |  -2.5  27.5  300  26 13   7.5   4.1
 16500  -1.4  29.5  300  26 13   7.1   3.9 |  -1.4  29.5  300  25 13   8.3   4.5
 16000  -0.4  31.3  305  24 13   7.1   3.9 |  -0.3  31.5  300  23 12   8.4   4.6
 15500   0.6  33.1  305  23 12   8.1   4.4 |   0.9  33.6  305  22 11   8.6   4.7
 15000   1.8  35.2  305  22 12   8.4   4.6 |   2.0  35.6  305  20 10   8.7   4.7
 14500   3.5  38.3  305  21 11   8.4   4.6 |   3.2  37.8  310  18  9   8.5   4.7
 14000   4.6  40.3  310  19 10   8.5   4.7 |   5.0  41.0  315  15  8   8.2   4.5
 13500   5.8  42.4  310  18  9   8.1   4.4 |   6.1  43.0  320  14  7   7.9   4.3
 13000   6.9  44.4  315  16  8   8.0   4.4 |   7.2  45.0  330  13  7   7.8   4.3
 12500   8.0  46.4  320  14  7   8.0   4.4 |   8.3  46.9  340  12  6   8.0   4.4
 12000   9.2  48.6  325  13  7   7.9   4.4 |   9.5  49.1  345  11  6   8.1   4.5
 11500  10.5  50.9  330  11  6   7.8   4.3 |  10.7  51.3  350  10  5   8.2   4.5
 11000  11.5  52.7  330   9  5   7.5   4.1 |  11.9  53.4  350   9  5   8.0   4.4
 10500  12.6  54.7  335   7  3   4.9   2.7 |  13.1  55.6  350   9  4   4.6   2.5
 10250  12.9  55.2  335   6  3   7.4   4.1 |  13.4  56.1  350   8  4   6.0   3.3
 10000  13.8  56.8  335   6  3  12.6   6.9 |  14.1  57.4  350   8  4  11.7   6.4
  9750  14.6  58.3  335   6  3  11.9   6.5 |  14.9  58.8  350   8  4  10.7   5.9
  9500  15.5  59.9  335   6  3   9.6   5.3 |  15.7  60.3  350   7  4   9.2   5.1
  9250  16.1  61.0  340   5  3   7.9   4.3 |  16.3  61.3  350   7  4   8.3   4.6
  9000  16.8  62.2  340   5  3  10.4   5.7 |  17.0  62.6  350   7  4  10.4   5.7
  8750  17.6  63.7  340   5  3  10.7   5.9 |  17.7  63.9  350   7  4  10.9   6.0
  8500  18.4  65.1  340   5  3  10.6   5.8 |  18.5  65.3  350   7  3   9.9   5.4
  8250  19.1  66.4  340   5  3  10.7   5.9 |  19.2  66.6  345   7  3   8.9   4.9
  8000  19.9  67.8  340   5  3  10.2   5.6 |  19.9  67.8  345   7  3   9.7   5.3
  7750  20.7  69.3  335   5  3   9.7   5.3 |  20.7  69.3  345   7  3  10.1   5.6
  7500  21.4  70.5  335   5  3  10.0   5.5 |  21.4  70.5  345   7  3  10.1   5.6
  7250  22.1  71.8  335   5  3  10.3   5.7 |  22.2  72.0  345   7  3  10.3   5.6
  7000  22.9  73.2  335   5  3   9.7   5.3 |  22.9  73.2  345   7  3  10.1   5.5
  6750  23.6  74.5  335   5  3   9.6   5.3 |  23.7  74.7  345   7  3  10.0   5.5
  6500  24.4  75.9  335   5  3  10.6   5.8 |  24.4  75.9  340   7  3  10.2   5.6
  6250  25.2  77.4  335   5  3  11.6   6.4 |  25.2  77.4  340   7  3  10.6   5.8
  6000  26.0  78.8  335   5  3   9.0   5.0 |  25.9  78.6  340   7  3   9.3   5.1
  5750  26.7  80.1  335   5  3  13.9   7.6 |  26.6  79.9  340   7  3  11.3   6.2
  5500  28.3  82.9  335   5  3  29.0  15.9 |  27.7  81.9  340   7  3  18.4  10.1
________________________________________________________________________________

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.

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



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.