Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280122
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1922 MDT Wednesday, August 27, 2014

This forecast is for Thursday, August 28, 2014:

If the trigger temperature of 68.8 F/20.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 660 ft/min (3.4 m/s)
   Maximum height of thermals.................. 13314 ft MSL (8027 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1015 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9990 ft MSL (4703 ft AGL)
Thermal soaring outlook for Friday 08/29....... 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 NVA
Potential height of wave....................... 14392 ft MSL (9105 ft AGL)
Wave soaring outlook for Friday 08/29.......... Fair

Remarks...

Sunrise/Sunset.................... 06:23:46 / 19:38:11 MDT
Total possible sunshine........... 13 hr 14 min 26 sec (794 min 26 sec)
Altitude of sun at 13:00:34 MDT... 59.76 degrees

Upper air data from numerical model forecast valid on 08/28/2014 at 0600 MDT

Freezing level.................. 13288 ft MSL (8001 ft AGL)
Convective condensation level... 12681 ft MSL (7394 ft AGL)
Lifted condensation level....... 13039 ft MSL (7751 ft AGL)
Lifted index.................... -0.4
K index......................... +26.3

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  -60.1 -76.2   220   17    9   2.7   1.5      M     M       M      M    M
 45000  -54.9 -66.8   215   28   15   4.8   2.6      M     M       M      M    M
 40000  -47.9 -54.2   205   36   19   1.2   0.7      M     M       M      M    M
 38000  -47.5 -53.5   210   31   16   0.8   0.4      M     M       M      M    M
 36000  -47.0 -52.6   210   26   13   0.7   0.4      M     M       M      M    M
 34000  -44.4 -47.9   215   23   12   6.5   3.6      M     M       M      M    M
 32000  -40.5 -40.9   225   22   11   6.5   3.6      M     M       M      M    M
 30000  -35.3 -31.5   225   19   10   8.5   4.6   40.2 104.4    12.4      M    M
 29000  -32.7 -26.9   230   18    9   8.5   4.6   39.8 103.6    12.1      M    M
 28000  -30.2 -22.4   230   17    9   8.5   4.6   39.4 102.9    12.0      M    M
 27000  -27.7 -17.9   230   16    8   8.2   4.5   38.8 101.8    11.6      M    M
 26000  -25.3 -13.5   230   15    8   8.2   4.5   38.1 100.7    11.3      M    M
 25000  -22.8  -9.0   230   14    7   8.3   4.5   37.7  99.8    11.0      M    M
 24000  -20.6  -5.1   230   13    7   7.1   3.9   36.8  98.3    10.4      M    M
 23000  -18.5  -1.3   230   11    6   7.2   3.9   35.8  96.5     9.7      M    M
 22000  -16.4   2.5   230    9    5   7.3   4.0   35.0  95.0     9.0      M    M
 21000  -14.4   6.1   230    8    4   6.5   3.6   33.9  92.9     8.1      M    M
 20000  -12.5   9.5   230    6    3   6.5   3.6   32.7  90.8     7.2      M    M
 19500  -11.5  11.3   230    5    3   6.5   3.6   32.2  89.9     6.7      M    M
 19000  -10.6  12.9   230    5    2   6.5   3.5   31.6  89.0     6.3      M    M
 18500   -9.7  14.5   235    4    2   6.4   3.5   31.0  87.9     5.8      M    M
 18000   -8.7  16.3   245    4    2   6.5   3.5   30.5  86.9     5.3      M    M
 17500   -7.8  18.0   255    3    2   6.3   3.5   29.9  85.8     4.8      M    M
 17000   -6.9  19.6   265    3    2   6.3   3.5   29.3  84.8     4.3      M    M
 16500   -6.0  21.2   275    3    2   6.6   3.6   28.8  83.8     3.8      M    M
 16000   -5.0  23.0   275    4    2   6.8   3.7   28.2  82.8     3.3      M    M
 15500   -4.0  24.8   280    4    2   6.8   3.7   27.7  81.9     2.9      M    M
 15000   -2.5  27.5   285    5    2   6.9   3.8   27.0  80.7     2.2      M    M
 14500   -1.5  29.3   290    5    3   5.9   3.3   26.6  79.9     1.8      M    M
 14000   -0.8  30.6   295    6    3   4.8   2.6   25.8  78.4     0.9      M    M
 13500   -0.2  31.6   300    7    3   5.1   2.8   25.0  76.9     0.1      M    M
 13000    0.6  33.1   305    7    4   6.2   3.4   24.3  75.8    -0.5    628  3.2
 12500    1.5  34.7   310    7    4   6.5   3.6   23.7  74.7    -1.1    587  3.0
 12000    2.7  36.9   320    7    4   9.1   5.0   23.5  74.2    -1.4    537  2.7
 11500    4.0  39.2   335    8    4   8.8   4.8   23.3  74.0    -1.6    483  2.5
 11000    5.1  41.2   350    9    5   7.0   3.8   23.0  73.4    -1.9    435  2.2
 10500    6.1  43.0   360   11    6   5.8   3.2   22.6  72.7    -2.4    389  2.0
 10250    6.4  43.5   005   12    6   4.8   2.7   22.2  72.0    -2.8    372  1.9
 10000    6.9  44.4   005   13    7   7.9   4.3   22.0  71.5    -3.0    350  1.8
  9750    7.6  45.7   005   15    8   9.3   5.1   21.9  71.4    -3.1    324  1.6
  9500    8.2  46.8   010   16    8   8.5   4.6   21.8  71.3    -3.2    297  1.5
  9250    8.8  47.8   010   17    9   6.8   3.7   21.7  71.0    -3.4    272  1.4
  9000    9.3  48.7   010   18    9   7.7   4.2   21.5  70.6    -3.6    249  1.3
  8750   10.0  50.0   005   19   10   9.3   5.1   21.4  70.5    -3.6    221  1.1
  8500   10.7  51.3   005   19   10   8.6   4.7   21.3  70.4    -3.6    192  1.0
  8250   11.4  52.5   005   18    9   8.3   4.6   21.2  70.2    -3.7    166  0.8
  8000   12.0  53.6   360   17    9   8.1   4.4   21.1  70.0    -3.8    140  0.7
  7750   12.6  54.7   360   16    8   7.9   4.3   21.0  69.7    -4.0    115  0.6
  7500   13.1  55.6   360   15    8   7.4   4.1   20.8  69.5    -4.2     90  0.5
  7250   13.7  56.7   355   15    8   6.8   3.8   20.6  69.1    -4.4     67  0.3
  7000   14.2  57.6   350   15    8   7.4   4.1   20.4  68.7    -4.6     43  0.2
  6750   14.8  58.6   345   15    8   6.5   3.6   20.2  68.4    -4.7     19  0.1
  6500   15.1  59.2   340   14    7   3.2   1.7   19.8  67.7    -5.1      1  0.0
  6250   15.2  59.4   330   14    7   1.1   0.6   19.2  66.6    -5.8      M    M
  6000   15.3  59.5   320   13    7   3.7   2.0   18.6  65.6    -6.4      M    M
  5750   15.6  60.1   315   13    7  -0.3  -0.2   18.2  64.7    -6.9      M    M
  5500   14.9  58.8   305    8    4 -12.4  -6.8   17.0  62.6    -8.3      M    M

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

           08/28/2014 at 0900 MDT          |       08/28/2014 at 1200 MDT
                                           |
K index... +29.1  LI... -1.3               | K index... +25.7  LI... -0.2
CAPE... +80.9  CIN... -1.0                 | CAPE... +43.6  CIN... -5.5
                                           |
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 -59.3 -74.7  235  12  6   2.3   1.3 | -59.2 -74.6  255   7  4   2.6   1.4
 45000 -55.1 -67.2  230  16  8   3.7   2.0 | -55.2 -67.4  260   7  4   2.5   1.4
 40000 -49.7 -57.5  220  15  8   2.0   1.1 | -51.4 -60.5  320   9  4   2.6   1.4
 38000 -48.7 -55.7  240  11  6   1.7   0.9 | -49.8 -57.6  355  18  9   2.6   1.5
 36000 -47.6 -53.7  275   9  5   1.7   0.9 | -48.2 -54.8  005  29 15   2.7   1.5
 34000 -44.6 -48.3  285  10  5   7.1   3.9 | -44.4 -47.9  005  28 15   8.3   4.5
 32000 -40.3 -40.5  285  11  6   7.0   3.9 | -39.4 -38.9  010  22 11   8.3   4.5
 30000 -34.9 -30.8  280  10  5   8.6   4.7 | -34.0 -29.2  005  15  8   7.9   4.3
 29000 -32.3 -26.1  280   9  4   8.6   4.7 | -31.6 -24.9  360  12  6   7.9   4.3
 28000 -29.8 -21.6  275   8  4   8.6   4.7 | -29.3 -20.7  355   9  5   7.9   4.4
 27000 -27.3 -17.1  275   7  4   8.2   4.5 | -26.8 -16.2  345   8  4   8.2   4.5
 26000 -24.9 -12.8  270   7  4   8.2   4.5 | -24.4 -11.9  340   8  4   8.2   4.5
 25000 -22.4  -8.3  270   7  4   8.2   4.5 | -22.0  -7.6  335   8  4   8.2   4.5
 24000 -20.2  -4.4  265   7  3   7.1   3.9 | -19.7  -3.5  335   8  4   7.5   4.1
 23000 -18.1  -0.6  255   6  3   7.1   3.9 | -17.4   0.7  330   9  5   7.5   4.1
 22000 -16.0   3.2  250   6  3   7.3   4.0 | -15.2   4.6  325   9  5   7.7   4.2
 21000 -14.2   6.4  245   6  3   5.6   3.1 | -13.3   8.1  320   9  5   6.0   3.3
 20000 -12.6   9.3  245   5  3   5.6   3.1 | -11.6  11.1  310   9  5   6.1   3.3
 19500 -11.8  10.8  245   5  2   5.7   3.1 | -10.7  12.7  305   9  5   6.1   3.3
 19000 -11.0  12.2  240   4  2   5.9   3.2 |  -9.8  14.4  305   9  4   6.0   3.3
 18500 -10.2  13.6  250   4  2   6.1   3.3 |  -8.9  16.0  300   9  5   5.9   3.2
 18000  -9.3  15.3  255   3  2   6.1   3.3 |  -8.1  17.4  300   9  5   5.8   3.2
 17500  -8.4  16.9  270   3  2   6.3   3.5 |  -7.2  19.0  300   9  5   6.4   3.5
 17000  -7.5  18.5  290   3  2   6.3   3.5 |  -6.3  20.7  300   9  4   6.4   3.5
 16500  -6.6  20.1  305   3  2   6.2   3.4 |  -5.4  22.3  305   8  4   5.2   2.8
 16000  -5.7  21.7  320   4  2   6.1   3.3 |  -4.8  23.4  305   8  4   4.5   2.5
 15500  -4.9  23.2  330   5  3   6.1   3.4 |  -3.9  25.0  315   9  4   5.2   2.9
 15000  -3.5  25.7  340   7  3   6.4   3.5 |  -3.1  26.4  315   9  5   5.4   2.9
 14500  -2.6  27.3  345   8  4   6.4   3.5 |  -2.4  27.7  315   9  5   6.2   3.4
 14000  -1.7  28.9  350   8  4   6.4   3.5 |  -1.4  29.5  320   9  5   6.9   3.8
 13500  -0.8  30.6  355   8  4   6.5   3.6 |  -0.4  31.3  320   9  5   7.1   3.9
 13000   0.2  32.4  360   9  4   6.8   3.8 |   0.6  33.1  325   8  4   7.4   4.1
 12500   1.1  34.0  010   9  5   6.9   3.8 |   1.7  35.1  325   7  4   7.3   4.0
 12000   2.2  36.0  020  11  5   7.4   4.1 |   2.6  36.7  325   8  4   6.6   3.6
 11500   3.2  37.8  030  13  7   7.3   4.0 |   3.6  38.5  325   9  4   6.2   3.4
 11000   4.2  39.6  025  14  7   6.4   3.5 |   4.2  39.6  330   9  5   3.3   1.8
 10500   5.1  41.2  020  15  7   4.4   2.4 |   4.8  40.6  335  10  5   2.7   1.5
 10250   5.4  41.7  020  15  8   3.7   2.0 |   5.0  41.0  340  10  5   3.9   2.2
 10000   5.9  42.6  020  16  8   9.2   5.0 |   5.5  41.9  345  11  6   8.3   4.6
  9750   6.7  44.1  015  17  9  11.4   6.2 |   6.2  43.2  350  12  6   9.8   5.4
  9500   7.5  45.5  015  18  9   9.5   5.2 |   6.9  44.4  355  13  7   8.7   4.8
  9250   8.1  46.6  010  18  9   6.2   3.4 |   7.5  45.5  355  14  7   6.9   3.8
  9000   8.5  47.3  010  19 10   7.6   4.2 |   8.0  46.4  360  15  8   8.1   4.4
  8750   9.3  48.7  010  19 10   9.9   5.4 |   8.7  47.7  360  16  8   9.8   5.4
  8500  10.0  50.0  010  19 10   8.9   4.9 |   9.4  48.9  005  17  9   8.5   4.7
  8250  10.6  51.1  005  18  9   8.6   4.7 |  10.0  50.0  005  16  8   7.6   4.2
  8000  11.3  52.3  005  17  9   8.5   4.7 |  10.5  50.9  005  16  8   8.1   4.4
  7750  11.9  53.4  360  15  8   8.3   4.5 |  11.2  52.2  005  15  8   8.7   4.8
  7500  12.5  54.5  360  14  7   8.1   4.4 |  11.8  53.2  005  14  7   8.8   4.8
  7250  13.1  55.6  355  13  7   8.0   4.4 |  12.5  54.5  005  13  7   8.7   4.8
  7000  13.8  56.8  350  12  6   7.9   4.4 |  13.1  55.6  005  11  6   8.6   4.7
  6750  14.3  57.7  350  11  6   7.5   4.1 |  13.7  56.7  010  10  5   8.8   4.8
  6500  14.9  58.8  345  10  5   7.0   3.8 |  14.4  57.9  010   9  5   9.5   5.2
  6250  15.4  59.7  340   9  5   7.7   4.2 |  15.1  59.2  010   8  4   9.3   5.1
  6000  15.8  60.4  335   8  4   5.1   2.8 |  15.7  60.3  010   7  3  10.4   5.7
  5750  16.1  61.0  320   7  4   8.1   4.4 |  16.6  61.9  005   6  3  12.5   6.9
  5500  17.2  63.0  320   6  3  20.5  11.2 |  17.5  63.5  005   6  3  12.7   7.0

           08/28/2014 at 1500 MDT          |       08/28/2014 at 1800 MDT
                                           |
K index... +26.4  LI... -0.5               | K index... +25.1  LI... -0.5
CAPE... +30.4  CIN... -2.2                 | CAPE... +48.7  CIN... -14.9
                                           |
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 -59.7 -75.5  285   7  4   2.5   1.4 | -60.3 -76.5  300  11  6   2.1   1.2
 45000 -55.9 -68.6  315   9  5   2.2   1.2 | -56.8 -70.2  330  17  9   2.5   1.4
 40000 -52.5 -62.5  350  24 13   3.8   2.1 | -53.0 -63.4  355  35 18   4.7   2.6
 38000 -50.2 -58.4  350  32 17   3.8   2.1 | -50.3 -58.5  360  37 19   4.4   2.4
 36000 -48.0 -54.4  355  40 21   3.9   2.1 | -47.6 -53.7  005  40 20   4.5   2.5
 34000 -43.8 -46.8  355  37 19   8.4   4.6 | -43.4 -46.1  005  37 19   8.2   4.5
 32000 -38.1 -36.6  355  28 14   8.3   4.6 | -37.9 -36.2  005  32 16   8.1   4.4
 30000 -33.2 -27.8  355  22 11   8.2   4.5 | -32.8 -27.0  005  28 15   8.5   4.7
 29000 -30.7 -23.3  350  20 10   8.2   4.5 | -30.3 -22.5  005  26 14   8.5   4.7
 28000 -28.3 -18.9  350  17  9   8.1   4.4 | -27.7 -17.9  005  25 13   8.4   4.6
 27000 -25.9 -14.6  345  15  8   7.8   4.3 | -25.3 -13.5  360  23 12   8.1   4.4
 26000 -23.6 -10.5  340  14  7   7.8   4.3 | -22.9  -9.2  360  22 11   8.1   4.4
 25000 -21.3  -6.3  335  12  6   7.9   4.3 | -20.5  -4.9  360  20 10   8.2   4.5
 24000 -19.1  -2.4  335  11  6   7.0   3.9 | -18.2  -0.8  360  19 10   7.3   4.0
 23000 -17.0   1.4  330  11  6   7.1   3.9 | -16.0   3.2  355  18  9   7.4   4.0
 22000 -15.0   5.0  325  11  6   7.2   4.0 | -13.9   7.0  355  17  9   7.7   4.2
 21000 -13.1   8.4  325  11  6   6.2   3.4 | -12.2  10.0  350  16  8   5.1   2.8
 20000 -11.3  11.7  320  12  6   6.3   3.4 | -10.8  12.6  345  15  8   5.2   2.9
 19500 -10.4  13.3  320  12  6   6.3   3.5 | -10.0  14.0  340  14  7   5.3   2.9
 19000  -9.6  14.7  320  12  6   6.1   3.4 |  -9.3  15.3  340  14  7   6.9   3.8
 18500  -8.7  16.3  320  12  6   6.0   3.3 |  -8.1  17.4  335  14  7   7.9   4.3
 18000  -7.9  17.8  315  12  6   6.0   3.3 |  -7.0  19.4  335  14  7   8.1   4.5
 17500  -7.0  19.4  310  12  6   5.8   3.2 |  -6.1  21.0  335  14  7   4.7   2.6
 17000  -6.2  20.8  305  12  6   5.8   3.2 |  -5.3  22.5  335  15  8   5.1   2.8
 16500  -5.3  22.5  305  13  7   6.1   3.4 |  -4.6  23.7  335  15  8   4.9   2.7
 16000  -4.4  24.1  300  13  7   6.3   3.5 |  -3.9  25.0  335  16  8   4.8   2.7
 15500  -3.0  26.6  300  13  7   5.9   3.2 |  -2.9  26.8  335  18  9   4.9   2.7
 15000  -2.2  28.0  300  14  7   5.9   3.2 |  -2.1  28.2  335  18  9   5.0   2.7
 14500  -1.4  29.5  300  14  7   5.9   3.2 |  -1.4  29.5  335  19 10   5.2   2.8
 14000  -0.5  31.1  300  14  7   5.9   3.2 |  -0.6  30.9  340  19 10   5.4   2.9
 13500   0.3  32.5  300  15  8   5.9   3.2 |   0.1  32.2  340  19 10   5.5   3.0
 13000   1.2  34.2  300  14  7   5.8   3.2 |   1.0  33.8  345  19 10   5.9   3.2
 12500   2.0  35.6  305  14  7   5.9   3.2 |   1.8  35.2  345  18  9   6.1   3.4
 12000   2.9  37.2  310  13  7   5.9   3.3 |   2.8  37.0  345  18  9   7.4   4.1
 11500   3.8  38.8  315  13  7   5.9   3.2 |   3.9  39.0  350  17  9   7.4   4.0
 11000   4.6  40.3  325  12  6   5.6   3.1 |   5.0  41.0  345  17  9   7.6   4.1
 10500   5.4  41.7  340  11  6   3.6   2.0 |   6.1  43.0  345  16  8   5.8   3.2
 10250   5.6  42.1  345  11  6   4.3   2.3 |   6.4  43.5  345  16  8   5.4   3.0
 10000   6.1  43.0  345  11  5   9.8   5.4 |   7.0  44.6  345  16  8   9.3   5.1
  9750   6.8  44.2  350  10  5  11.0   6.0 |   7.7  45.9  340  15  8  10.2   5.6
  9500   7.6  45.7  350  10  5  10.0   5.5 |   8.4  47.1  340  14  7   9.2   5.0
  9250   8.2  46.8  350  10  5   8.4   4.6 |   9.0  48.2  340  14  7   7.4   4.0
  9000   8.9  48.0  350  10  5   9.7   5.3 |   9.6  49.3  340  13  7   8.5   4.6
  8750   9.7  49.5  350   9  5  11.3   6.2 |  10.3  50.5  335  13  7   9.9   5.4
  8500  10.5  50.9  350   9  5  10.4   5.7 |  11.0  51.8  335  12  6   9.1   5.0
  8250  11.2  52.2  350   9  5   9.8   5.4 |  11.6  52.9  335  12  6   8.6   4.7
  8000  12.0  53.6  350   9  5  10.0   5.5 |  12.2  54.0  330  12  6   8.8   4.8
  7750  12.7  54.9  350   9  5  10.3   5.7 |  12.8  55.0  330  11  6   8.9   4.9
  7500  13.5  56.3  350   9  5  10.0   5.5 |  13.4  56.1  330  11  6   9.6   5.3
  7250  14.2  57.6  350   9  5   9.7   5.3 |  14.2  57.6  330  11  6  10.2   5.6
  7000  15.0  59.0  350   9  5   9.8   5.4 |  14.9  58.8  330  11  6   9.8   5.4
  6750  15.7  60.3  350   9  5  10.4   5.7 |  15.6  60.1  330  11  5   9.7   5.3
  6500  16.5  61.7  345   9  5  10.7   5.9 |  16.4  61.5  325  10  5  10.3   5.6
  6250  17.3  63.1  345   9  4  11.4   6.2 |  17.2  63.0  325  10  5  10.9   6.0
  6000  18.1  64.6  345   8  4   9.0   4.9 |  17.9  64.2  325  10  5   9.5   5.2
  5750  18.8  65.8  345   8  4  13.9   7.6 |  18.6  65.5  325  10  5  10.5   5.8
  5500  20.4  68.7  345   8  4  29.0  15.9 |  19.6  67.3  325   9  5  15.7   8.6
________________________________________________________________________________

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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