Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240122
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1922 MDT Tuesday, September 23, 2014

This forecast is for Wednesday, September 24, 2014:

If the trigger temperature of 75.0 F/23.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 813 ft/min (4.1 m/s)
   Maximum height of thermals.................. 14820 ft MSL (9533 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1115 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................. 12101 ft MSL (6814 ft AGL)
Thermal soaring outlook for Thursday 09/25..... 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 NVA
Potential height of wave....................... 35795 ft MSL (30508 ft AGL)
Wave soaring outlook for Thursday 09/25........ Poor

Remarks... Strong high pressure ridge will shift eastward over colorado during
           the outlook period.

Sunrise/Sunset.................... 06:49:01 / 18:54:47 MDT
Total possible sunshine........... 12 hr 5 min 46 sec (725 min 46 sec)
Altitude of sun at 12:51:24 MDT... 49.59 degrees

Upper air data from numerical model forecast valid on 09/24/2014 at 0600 MDT

Freezing level.................. 14723 ft MSL (9436 ft AGL)
Convective condensation level... 14514 ft MSL (9227 ft AGL)
Lifted condensation level....... 14721 ft MSL (9433 ft AGL)
Lifted index.................... -1.3
K index......................... +20.6

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  -64.9 -84.8   325   15    8   2.2   1.2      M     M       M      M    M
 45000  -59.9 -75.8   330   30   16   5.6   3.1      M     M       M      M    M
 40000  -51.5 -60.7   345   39   20   4.9   2.7      M     M       M      M    M
 38000  -48.6 -55.5   355   44   23   4.9   2.7      M     M       M      M    M
 36000  -45.7 -50.3   005   50   26   4.8   2.6      M     M       M      M    M
 34000  -41.7 -43.1   005   50   26   7.1   3.9      M     M       M      M    M
 32000  -37.5 -35.5   010   48   25   7.1   3.9      M     M       M      M    M
 30000  -32.2 -26.0   005   44   23   8.1   4.4   43.4 110.1    11.4      M    M
 29000  -29.8 -21.6   360   42   22   8.1   4.4   42.8 109.0    11.1      M    M
 28000  -27.4 -17.3   355   40   21   7.5   4.1   42.2 108.0    10.8      M    M
 27000  -25.2 -13.4   355   37   19   7.4   4.1   41.2 106.2    10.1      M    M
 26000  -23.0  -9.4   355   33   17   7.4   4.1   40.3 104.6     9.5      M    M
 25000  -20.8  -5.4   355   30   15   7.5   4.1   39.5 103.2     9.0      M    M
 24000  -18.5  -1.3   350   28   14   7.9   4.3   38.7 101.7     8.4      M    M
 23000  -16.1   3.0   350   26   13   7.9   4.3   38.0 100.5     7.9      M    M
 22000  -13.8   7.2   345   24   12   7.5   4.1   37.5  99.4     7.5      M    M
 21000  -11.8  10.8   345   22   11   6.6   3.6   36.3  97.3     6.5      M    M
 20000   -9.9  14.2   345   20   10   6.7   3.7   35.2  95.4     5.6      M    M
 19500   -8.9  16.0   345   19   10   6.8   3.7   34.7  94.5     5.2      M    M
 19000   -8.0  17.6   345   18    9   6.1   3.4   34.2  93.5     4.7      M    M
 18500   -7.1  19.2   345   18    9   6.1   3.4   33.5  92.4     4.2      M    M
 18000   -6.2  20.8   345   17    9   6.0   3.3   32.9  91.3     3.6      M    M
 17500   -5.3  22.5   345   17    9   5.8   3.2   32.2  90.0     3.0      M    M
 17000   -4.4  24.1   345   17    9   5.8   3.2   31.6  88.9     2.5      M    M
 16500   -3.6  25.5   345   16    8   6.2   3.4   31.0  87.7     1.9      M    M
 16000   -2.6  27.3   345   16    8   6.2   3.4   30.4  86.6     1.4      M    M
 15500   -1.7  28.9   345   16    8   6.4   3.5   29.8  85.6     0.8      M    M
 15000   -0.3  31.5   345   15    8   6.6   3.6   29.0  84.1     0.1      M    M
 14500    0.6  33.1   345   15    8   6.1   3.3   28.4  83.2    -0.5    777  3.9
 14000    1.5  34.7   345   14    7   6.1   3.3   27.8  82.0    -1.1    736  3.7
 13500    2.3  36.1   345   14    7   6.6   3.6   27.2  81.0    -1.7    696  3.5
 13000    3.2  37.8   345   13    7   6.8   3.7   26.7  80.1    -2.3    653  3.3
 12500    4.2  39.6   345   12    6   7.5   4.1   26.3  79.3    -2.8    610  3.1
 12000    5.3  41.5   350   12    6   8.1   4.5   26.0  78.8    -3.1    561  2.8
 11500    6.5  43.7   350   12    6   8.4   4.6   25.8  78.4    -3.4    512  2.6
 11000    7.8  46.0   350   11    6   8.4   4.6   25.6  78.1    -3.6    459  2.3
 10500    9.0  48.2   350   10    5   3.7   2.0   25.4  77.8    -3.8    405  2.1
 10250    9.1  48.4   350   10    5   5.0   2.8   24.8  76.6    -4.5    395  2.0
 10000   10.0  50.0   350    9    5  13.3   7.3   24.9  76.8    -4.4    363  1.8
  9750   10.9  51.6   350    8    4  12.8   7.0   25.1  77.2    -4.2    328  1.7
  9500   11.7  53.1   350    7    3   9.1   5.0   25.3  77.5    -4.1    295  1.5
  9250   12.2  54.0   350    6    3   5.5   3.0   25.0  77.0    -4.3    273  1.4
  9000   12.8  55.0   345    6    3   9.0   4.9   24.8  76.7    -4.5    249  1.3
  8750   13.5  56.3   340    5    2  10.3   5.7   24.8  76.7    -4.5    220  1.1
  8500   14.2  57.6   335    4    2   9.0   4.9   24.8  76.7    -4.6    191  1.0
  8250   14.9  58.8   330    4    2   8.2   4.5   24.7  76.5    -4.7    165  0.8
  8000   15.5  59.9   320    4    2   9.2   5.1   24.6  76.4    -4.8    138  0.7
  7750   16.2  61.2   315    4    2  10.0   5.5   24.6  76.4    -4.8    109  0.6
  7500   16.9  62.4   310    5    2   9.5   5.2   24.6  76.4    -4.8     80  0.4
  7250   17.6  63.7   310    5    3   9.0   5.0   24.6  76.3    -4.9     52  0.3
  7000   18.3  64.9   310    6    3  10.0   5.5   24.6  76.2    -4.9     24  0.1
  6750   19.0  66.2   305    6    3   7.5   4.1   24.6  76.2    -4.9      M    M
  6500   19.4  66.9   300    7    4   3.4   1.9   24.2  75.5    -5.3      M    M
  6250   19.7  67.5   295    8    4   7.9   4.3   23.8  74.9    -5.7      M    M
  6000   20.1  68.2   290    9    5  -6.6  -3.6   23.4  74.2    -6.1      M    M
  5750   18.3  64.9   275    9    4 -33.8 -18.5   21.0  69.9    -8.6      M    M
  5500   15.4  59.7   250    6    3 -35.6 -19.6   17.6  63.6   -12.2     68  0.3

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

           09/24/2014 at 0900 MDT          |       09/24/2014 at 1200 MDT
                                           |
K index... +20.4  LI... +1.4               | K index... +18.0  LI... +0.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -65.2 -85.4  325  13  7   2.4   1.3 | -65.2 -85.4  325  15  8   2.6   1.4
 45000 -60.1 -76.2  340  29 15   5.1   2.8 | -60.0 -76.0  350  26 14   5.0   2.8
 40000 -52.4 -62.3  360  39 20   5.1   2.8 | -52.4 -62.3  015  35 18   5.2   2.8
 38000 -49.4 -56.9  010  45 23   5.1   2.8 | -49.3 -56.7  020  43 22   5.2   2.8
 36000 -46.3 -51.3  020  53 27   4.9   2.7 | -46.2 -51.2  030  53 27   4.9   2.7
 34000 -41.8 -43.2  020  56 29   8.0   4.4 | -41.5 -42.7  025  52 27   8.1   4.5
 32000 -37.0 -34.6  020  57 29   8.0   4.4 | -36.0 -32.8  020  50 26   8.3   4.6
 30000 -31.7 -25.1  015  48 25   7.7   4.2 | -31.3 -24.3  020  44 23   7.9   4.3
 29000 -29.4 -20.9  015  42 22   7.7   4.2 | -28.9 -20.0  020  41 21   7.9   4.3
 28000 -27.1 -16.8  010  38 20   8.1   4.4 | -26.5 -15.7  020  38 20   8.4   4.6
 27000 -24.6 -12.3  005  37 19   8.2   4.5 | -24.0 -11.2  015  36 19   8.4   4.6
 26000 -22.2  -8.0  005  35 18   8.2   4.5 | -21.4  -6.5  010  34 17   8.4   4.6
 25000 -19.8  -3.6  360  35 18   8.0   4.4 | -18.9  -2.0  005  32 16   8.0   4.4
 24000 -17.7   0.1  355  31 16   7.0   3.9 | -16.8   1.8  005  29 15   7.0   3.9
 23000 -15.6   3.9  355  28 14   7.1   3.9 | -14.7   5.5  005  27 14   7.1   3.9
 22000 -13.5   7.7  355  24 13   6.9   3.8 | -12.6   9.3  005  24 12   6.6   3.6
 21000 -11.6  11.1  350  22 11   6.5   3.6 | -10.9  12.4  360  21 11   5.9   3.2
 20000  -9.7  14.5  350  20 10   6.6   3.6 |  -9.2  15.4  360  18  9   6.0   3.3
 19500  -8.7  16.3  350  18  9   6.7   3.7 |  -8.3  17.1  355  17  9   6.0   3.3
 19000  -7.8  18.0  345  18  9   5.2   2.9 |  -7.5  18.5  355  16  8   5.8   3.2
 18500  -7.1  19.2  350  17  9   5.4   3.0 |  -6.6  20.1  355  15  8   5.8   3.2
 18000  -6.3  20.7  350  16  8   5.5   3.0 |  -5.7  21.7  355  14  7   5.8   3.2
 17500  -5.5  22.1  350  16  8   5.6   3.1 |  -4.9  23.2  355  13  7   5.8   3.2
 17000  -4.7  23.5  350  15  8   5.6   3.1 |  -4.0  24.8  355  13  7   5.8   3.2
 16500  -3.8  25.2  350  14  7   5.7   3.1 |  -3.2  26.2  355  12  6   6.0   3.3
 16000  -3.0  26.6  350  14  7   5.7   3.1 |  -1.9  28.6  350  11  5   5.9   3.3
 15500  -1.7  28.9  350  12  6   5.9   3.3 |  -1.0  30.2  350  10  5   5.8   3.2
 15000  -0.8  30.6  350  12  6   5.9   3.2 |  -0.1  31.8  345   9  4   5.8   3.2
 14500   0.1  32.2  355  11  6   6.7   3.7 |   0.7  33.3  345   8  4   6.1   3.3
 14000   1.0  33.8  355  11  6   6.7   3.7 |   1.6  34.9  345   7  4   6.1   3.3
 13500   1.9  35.4  355  11  5   6.8   3.7 |   2.5  36.5  350   6  3   6.7   3.7
 13000   2.9  37.2  360  10  5   6.9   3.8 |   3.4  38.1  355   6  3   6.9   3.8
 12500   3.9  39.0  360  10  5   7.8   4.3 |   4.4  39.9  360   5  3   7.8   4.3
 12000   5.1  41.2  360   9  5   8.3   4.6 |   5.6  42.1  360   4  2   8.2   4.5
 11500   6.3  43.3  360   9  5   8.8   4.8 |   6.7  44.1  360   4  2   8.3   4.5
 11000   7.6  45.7  360   8  4   9.0   4.9 |   7.9  46.2  360   3  2   8.3   4.5
 10500   8.9  48.0  355   8  4   4.4   2.4 |   9.1  48.4  355   3  2   4.3   2.4
 10250   9.1  48.4  355   8  4   5.7   3.1 |   9.3  48.7  355   3  2   6.2   3.4
 10000   9.9  49.8  355   7  4  12.8   7.0 |  10.1  50.2  350   3  2  12.2   6.7
  9750  10.8  51.4  355   6  3  12.2   6.7 |  11.0  51.8  345   3  2  11.2   6.1
  9500  11.6  52.9  350   5  3   9.1   5.0 |  11.7  53.1  340   3  2   8.6   4.7
  9250  12.1  53.8  345   4  2   6.8   3.7 |  12.3  54.1  335   3  1   6.8   3.8
  9000  12.7  54.9  340   4  2   9.4   5.1 |  12.9  55.2  330   3  1  10.5   5.7
  8750  13.5  56.3  330   3  2  10.0   5.5 |  13.7  56.7  315   2  1  11.5   6.3
  8500  14.2  57.6  315   2  1   8.1   4.5 |  14.5  58.1  305   2  1   8.8   4.8
  8250  14.7  58.5  305   2  1   7.4   4.1 |  15.1  59.2  290   2  1   8.0   4.4
  8000  15.3  59.5  295   2  1   7.8   4.3 |  15.7  60.3  275   3  1   8.6   4.7
  7750  15.9  60.6  285   3  1   8.2   4.5 |  16.3  61.3  265   3  1   9.1   5.0
  7500  16.5  61.7  290   3  2   8.4   4.6 |  17.0  62.6  265   3  1   9.2   5.0
  7250  17.1  62.8  300   3  2   8.1   4.5 |  17.6  63.7  270   3  1   9.1   5.0
  7000  17.8  64.0  310   4  2   9.3   5.1 |  18.3  64.9  275   2  1   9.4   5.2
  6750  18.4  65.1  320   4  2   6.8   3.7 |  19.0  66.2  280   2  1  10.3   5.6
  6500  18.7  65.7  315   5  2   3.0   1.7 |  19.8  67.6  280   2  1  10.6   5.8
  6250  19.0  66.2  315   5  3   6.2   3.4 |  20.6  69.1  285   2  1  10.7   5.9
  6000  19.3  66.7  315   6  3  -2.8  -1.5 |  21.3  70.3  285   2  1  10.0   5.5
  5750  18.5  65.3  300   5  3  -9.6  -5.3 |  22.2  72.0  285   2  1  14.2   7.8
  5500  18.2  64.8  275   4  2   4.9   2.7 |  23.6  74.5  290   2  1  23.1  12.6

           09/24/2014 at 1500 MDT          |       09/24/2014 at 1800 MDT
                                           |
K index... +13.7  LI... +0.5               | K index... +15.5  LI... +0.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.5
                                           |
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 -65.3 -85.5  335  17  9   2.6   1.4 | -65.4 -85.7  340  17  8   2.7   1.5
 45000 -60.1 -76.2  350  25 13   5.2   2.9 | -60.3 -76.5  345  26 13   4.9   2.7
 40000 -52.4 -62.3  360  29 15   4.9   2.7 | -52.8 -63.0  350  34 17   5.6   3.1
 38000 -49.4 -56.9  020  36 19   4.9   2.7 | -49.4 -56.9  015  36 19   5.6   3.1
 36000 -46.5 -51.7  030  46 23   4.5   2.5 | -46.0 -50.8  035  43 22   5.3   2.9
 34000 -41.8 -43.2  030  46 24   8.4   4.6 | -41.5 -42.7  040  47 24   7.8   4.3
 32000 -36.1 -33.0  035  46 23   8.5   4.7 | -36.2 -33.2  050  51 26   8.2   4.5
 30000 -31.1 -24.0  030  40 21   8.5   4.7 | -30.9 -23.6  040  43 22   8.8   4.9
 29000 -28.5 -19.3  025  37 19   8.5   4.7 | -28.2 -18.8  035  39 20   8.9   4.9
 28000 -26.0 -14.8  020  35 18   8.1   4.5 | -25.6 -14.1  030  35 18   8.2   4.5
 27000 -23.5 -10.3  015  34 17   8.1   4.5 | -23.2  -9.8  030  34 17   8.2   4.5
 26000 -21.1  -6.0  010  32 17   8.2   4.5 | -20.7  -5.3  025  33 17   8.2   4.5
 25000 -18.7  -1.7  005  31 16   7.7   4.2 | -18.3  -0.9  020  32 16   7.7   4.2
 24000 -16.6   2.1  005  28 15   6.8   3.7 | -16.2   2.8  020  29 15   7.0   3.8
 23000 -14.6   5.7  005  25 13   6.8   3.7 | -14.1   6.6  020  27 14   7.0   3.9
 22000 -12.6   9.3  010  22 11   6.4   3.5 | -12.1  10.2  015  24 12   6.2   3.4
 21000 -10.9  12.4  005  19 10   5.9   3.3 | -10.6  12.9  010  20 10   5.2   2.9
 20000  -9.2  15.4  005  16  8   6.0   3.3 |  -9.1  15.6  005  16  8   5.2   2.9
 19500  -8.3  17.1  360  14  7   6.0   3.3 |  -8.3  17.1  360  15  8   5.2   2.8
 19000  -7.4  18.7  360  13  7   6.3   3.5 |  -7.4  18.7  355  14  7   6.7   3.7
 18500  -6.5  20.3  355  12  6   6.3   3.5 |  -6.5  20.3  350  13  7   6.6   3.6
 18000  -5.5  22.1  350  11  6   6.4   3.5 |  -5.5  22.1  345  13  7   6.4   3.5
 17500  -4.6  23.7  350  11  6   6.4   3.5 |  -4.6  23.7  340  13  7   6.2   3.4
 17000  -3.6  25.5  345  10  5   6.4   3.5 |  -3.7  25.3  335  13  7   6.3   3.4
 16500  -2.6  27.3  345  10  5   7.1   3.9 |  -2.7  27.1  335  13  6   7.6   4.2
 16000  -1.0  30.2  340   9  5   7.0   3.8 |  -1.0  30.2  335  12  6   7.6   4.2
 15500  -0.0  32.0  340   9  4   6.8   3.7 |   0.2  32.4  330  12  6   8.0   4.4
 15000   1.0  33.8  335   8  4   6.8   3.7 |   1.4  34.5  330  11  6   8.0   4.4
 14500   2.0  35.6  335   7  4   6.9   3.8 |   2.6  36.7  330  10  5   7.9   4.3
 14000   3.1  37.6  330   7  3   6.9   3.8 |   3.7  38.7  330   9  5   7.9   4.4
 13500   4.1  39.4  325   6  3   7.2   4.0 |   4.9  40.8  330   8  4   7.5   4.1
 13000   5.1  41.2  320   5  3   7.3   4.0 |   6.0  42.8  335   7  4   7.5   4.1
 12500   6.2  43.2  320   4  2   7.3   4.0 |   7.0  44.6  335   5  3   7.0   3.8
 12000   7.2  45.0  320   2  1   7.4   4.0 |   8.1  46.6  335   2  1   6.8   3.7
 11500   8.3  46.9  315   1  0   7.5   4.1 |   9.1  48.4  150   1  1   7.3   4.0
 11000   9.4  48.9  000   0  0   7.5   4.1 |  10.2  50.4  140   3  1   7.6   4.2
 10500  10.4  50.7  145   1  0   2.5   1.4 |  11.2  52.2  135   5  2   3.1   1.7
 10250  10.5  50.9  145   1  0   5.3   2.9 |  11.3  52.3  135   5  2   5.7   3.1
 10000  11.2  52.2  140   1  0  12.6   6.9 |  12.1  53.8  130   5  2  12.3   6.8
  9750  12.0  53.6  135   1  1  10.9   6.0 |  12.9  55.2  130   5  2  10.6   5.8
  9500  12.7  54.9  135   1  1   8.8   4.8 |  13.6  56.5  130   5  3   8.7   4.8
  9250  13.2  55.8  135   1  1   7.2   4.0 |  14.1  57.4  125   5  2   7.2   4.0
  9000  13.8  56.8  140   1  1  10.1   5.5 |  14.7  58.5  125   5  2   9.6   5.3
  8750  14.6  58.3  135   1  1  11.0   6.0 |  15.4  59.7  120   4  2  10.3   5.6
  8500  15.3  59.5  135   1  1   9.7   5.3 |  16.1  61.0  120   4  2   9.4   5.2
  8250  16.0  60.8  135   1  0   9.1   5.0 |  16.8  62.2  120   4  2   8.9   4.9
  8000  16.7  62.1  135   1  0  10.0   5.5 |  17.4  63.3  115   4  2   9.8   5.4
  7750  17.5  63.5  135   1  0  10.4   5.7 |  18.2  64.8  115   4  2  10.3   5.7
  7500  18.3  64.9  135   1  0   9.8   5.4 |  18.9  66.0  115   3  2   9.7   5.3
  7250  19.0  66.2  145   1  0   9.6   5.3 |  19.6  67.3  115   3  2   9.8   5.4
  7000  19.7  67.5  150   1  0  10.2   5.6 |  20.4  68.7  110   3  2   9.5   5.2
  6750  20.5  68.9  150   1  0  10.5   5.7 |  21.1  70.0  110   3  1   9.5   5.2
  6500  21.3  70.3  155   1  0  10.3   5.6 |  21.8  71.2  110   3  1   9.8   5.4
  6250  22.0  71.6  160   1  0  10.2   5.6 |  22.5  72.5  110   2  1   9.6   5.2
  6000  22.8  73.0  000   0  0  10.8   5.9 |  23.2  73.8  110   2  1  10.3   5.6
  5750  23.8  74.8  000   0  0  15.4   8.5 |  24.0  75.2  105   2  1  10.4   5.7
  5500  25.1  77.2  000   0  0  20.9  11.5 |  24.6  76.3  105   2  1   8.5   4.7
________________________________________________________________________________

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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