Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 160121
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1921 MDT Monday, September 15, 2014

This forecast is for Tuesday, September 16, 2014:

If the trigger temperature of 81.2 F/27.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1019 ft/min (5.2 m/s)
   Maximum height of thermals.................. 16010 ft MSL (10723 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1145 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................. 7065 ft MSL (1777 ft AGL)
Thermal soaring outlook for Wednesday 09/17.... 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....................... 45950 ft MSL (40663 ft AGL)
Wave soaring outlook for Wednesday 09/17....... Poor

Remarks... None

Sunrise/Sunset.................... 06:41:29 / 19:07:55 MDT
Total possible sunshine........... 12 hr 26 min 26 sec (746 min 26 sec)
Altitude of sun at 12:54:13 MDT... 52.69 degrees

Upper air data from numerical model forecast valid on 09/16/2014 at 0600 MDT

Freezing level.................. 15025 ft MSL (9738 ft AGL)
Convective condensation level... 16581 ft MSL (11294 ft AGL)
Lifted condensation level....... 16502 ft MSL (11215 ft AGL)
Lifted index.................... -0.5
K index......................... +16.3

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  -65.8 -86.4   295   49   25   1.8   1.0      M     M       M      M    M
 45000  -61.6 -78.9   290   65   33   5.6   3.1      M     M       M      M    M
 40000  -53.2 -63.8   295   66   34   5.3   2.9      M     M       M      M    M
 38000  -50.0 -58.0   295   58   30   5.3   2.9      M     M       M      M    M
 36000  -46.8 -52.2   300   50   26   5.4   3.0      M     M       M      M    M
 34000  -42.7 -44.9   300   45   23   7.3   4.0      M     M       M      M    M
 32000  -37.7 -35.9   300   39   20   7.3   4.0      M     M       M      M    M
 30000  -33.1 -27.6   300   35   18   7.7   4.2   42.2 108.0     9.7      M    M
 29000  -30.8 -23.4   300   33   17   7.7   4.2   41.5 106.7     9.3      M    M
 28000  -28.5 -19.3   300   32   16   7.9   4.3   40.9 105.6     8.9      M    M
 27000  -26.1 -15.0   300   30   15   8.0   4.4   40.1 104.1     8.4      M    M
 26000  -23.7 -10.7   300   28   15   8.0   4.4   39.4 102.9     7.9      M    M
 25000  -21.3  -6.3   300   27   14   8.0   4.4   38.8 101.9     7.6      M    M
 24000  -19.1  -2.4   300   25   13   7.0   3.8   37.8 100.1     6.8      M    M
 23000  -17.0   1.4   300   23   12   7.0   3.8   36.8  98.2     6.1      M    M
 22000  -15.0   5.0   305   22   11   6.7   3.7   35.9  96.6     5.3      M    M
 21000  -13.3   8.1   305   22   11   5.4   2.9   34.3  93.8     4.0      M    M
 20000  -11.7  10.9   305   22   11   5.4   3.0   32.8  91.0     2.7      M    M
 19500  -11.0  12.2   305   22   11   5.2   2.9   32.1  89.7     2.1      M    M
 19000  -10.0  14.0   310   21   11   7.6   4.2   31.5  88.7     1.6      M    M
 18500   -8.9  16.0   305   20   10   7.6   4.2   31.1  88.0     1.2      M    M
 18000   -7.8  18.0   305   19   10   7.9   4.4   30.7  87.3     0.9      M    M
 17500   -6.5  20.3   305   18    9   8.6   4.7   30.5  86.9     0.7      M    M
 17000   -5.3  22.5   305   16    8   8.6   4.7   30.3  86.6     0.5      M    M
 16500   -3.4  25.9   300   15    8   8.4   4.6   30.0  86.0     0.2      M    M
 16000   -2.2  28.0   295   15    7   8.5   4.6   29.8  85.6    -0.1   1006  5.1
 15500   -0.9  30.4   295   14    7   8.6   4.7   29.6  85.2    -0.3    954  4.8
 15000    0.3  32.5   295   13    7   8.6   4.7   29.4  84.9    -0.5    901  4.6
 14500    1.6  34.9   295   12    6   8.9   4.9   29.2  84.6    -0.7    848  4.3
 14000    2.9  37.2   295   12    6   8.9   4.9   29.1  84.3    -0.8    794  4.0
 13500    4.2  39.6   300   12    6   9.2   5.1   28.9  84.1    -1.0    740  3.8
 13000    5.6  42.1   305   12    6   9.3   5.1   28.9  84.0    -1.1    684  3.5
 12500    7.0  44.6   310   13    7   9.3   5.1   28.8  83.9    -1.2    628  3.2
 12000    8.3  46.9   315   13    7   9.3   5.1   28.7  83.7    -1.3    573  2.9
 11500    9.7  49.5   315   14    7   9.2   5.1   28.7  83.6    -1.4    517  2.6
 11000   11.0  51.8   315   15    8   8.9   4.9   28.6  83.4    -1.5    461  2.3
 10500   12.4  54.3   315   15    8   4.0   2.2   28.5  83.3    -1.6    406  2.1
 10250   12.5  54.5   315   15    8   5.6   3.0   27.9  82.1    -2.2    395  2.0
 10000   13.4  56.1   315   15    8  13.1   7.2   28.0  82.4    -2.1    363  1.8
  9750   14.2  57.6   315   15    8  11.8   6.5   28.1  82.7    -2.0    330  1.7
  9500   15.1  59.2   310   15    8   9.6   5.3   28.3  82.9    -1.9    297  1.5
  9250   15.6  60.1   310   15    8   7.2   4.0   28.1  82.6    -2.1    273  1.4
  9000   16.2  61.2   310   15    8   9.8   5.4   28.0  82.5    -2.2    247  1.3
  8750   17.0  62.6   310   15    8  10.7   5.9   28.1  82.6    -2.2    217  1.1
  8500   17.7  63.9   310   14    7   9.4   5.2   28.1  82.6    -2.2    188  1.0
  8250   18.3  64.9   310   14    7   8.5   4.7   28.0  82.5    -2.3    161  0.8
  8000   19.0  66.2   310   14    7   8.9   4.9   28.0  82.3    -2.4    135  0.7
  7750   19.7  67.5   310   15    7   8.6   4.7   27.9  82.2    -2.5    107  0.5
  7500   20.3  68.5   310   15    7   7.3   4.0   27.8  82.0    -2.6     81  0.4
  7250   20.8  69.4   305   15    7   6.4   3.5   27.5  81.6    -2.8     59  0.3
  7000   21.3  70.3   305   15    7   7.4   4.0   27.3  81.1    -3.0     36  0.2
  6750   21.8  71.2   305   15    8   4.3   2.4   27.1  80.7    -3.3     14  0.1
  6500   21.8  71.2   300   14    7  -1.8  -1.0   26.4  79.5    -4.0      5  0.0
  6250   21.8  71.2   300   13    6   2.7   1.5   25.6  78.0    -4.8      M    M
  6000   21.7  71.1   295   11    6 -14.9  -8.2   24.8  76.6    -5.6      M    M
  5750   19.0  66.2   275    9    5 -47.2 -25.9   21.5  70.7    -9.0     66  0.3
  5500   15.1  59.2   245    6    3 -47.1 -25.8   17.0  62.7   -13.6    177  0.9

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

           09/16/2014 at 0900 MDT          |       09/16/2014 at 1200 MDT
                                           |
K index... +13.8  LI... +0.8               | K index... +18.4  LI... -0.9
CAPE... 0.0  CIN... M                      | CAPE... +24.8  CIN... -38.7
                                           |
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 -66.1 -87.0  295  49 25   1.7   0.9 | -65.9 -86.6  295  51 26   1.6   0.9
 45000 -62.2 -80.0  295  66 34   4.8   2.7 | -62.3 -80.1  290  65 33   4.6   2.5
 40000 -54.8 -66.6  295  62 32   6.6   3.6 | -55.2 -67.4  295  56 29   6.8   3.7
 38000 -50.8 -59.4  295  56 29   6.6   3.6 | -51.2 -60.2  300  53 27   6.7   3.7
 36000 -46.9 -52.4  305  50 26   6.6   3.6 | -47.1 -52.8  300  49 25   6.7   3.7
 34000 -41.8 -43.2  310  46 24   7.8   4.3 | -42.5 -44.5  305  46 23   8.1   4.4
 32000 -37.1 -34.8  315  44 23   7.8   4.3 | -37.0 -34.6  310  42 22   8.0   4.4
 30000 -32.4 -26.3  310  37 19   7.7   4.2 | -32.2 -26.0  305  35 18   8.0   4.4
 29000 -30.1 -22.2  310  33 17   7.7   4.2 | -29.8 -21.6  305  31 16   8.0   4.4
 28000 -27.8 -18.0  305  30 15   7.6   4.1 | -27.4 -17.3  300  27 14   7.8   4.3
 27000 -25.5 -13.9  305  28 14   7.5   4.1 | -25.1 -13.2  300  26 13   7.7   4.2
 26000 -23.3  -9.9  300  26 13   7.5   4.1 | -22.8  -9.0  300  24 12   7.7   4.2
 25000 -21.1  -6.0  300  24 12   7.5   4.1 | -20.5  -4.9  295  22 12   7.6   4.2
 24000 -18.8  -1.8  300  22 11   7.4   4.0 | -18.4  -1.1  290  22 11   6.5   3.6
 23000 -16.6   2.1  295  19 10   7.4   4.0 | -16.5   2.3  290  22 11   6.5   3.6
 22000 -14.4   6.1  290  17  9   6.6   3.6 | -14.5   5.9  285  22 11   6.1   3.4
 21000 -13.1   8.4  295  19 10   4.2   2.3 | -13.1   8.4  285  22 11   4.8   2.6
 20000 -11.8  10.8  295  20 10   4.4   2.4 | -11.7  10.9  290  22 12   4.8   2.6
 19500 -11.2  11.8  300  21 11   4.1   2.3 | -11.0  12.2  290  23 12   4.6   2.5
 19000 -10.4  13.3  300  22 11   7.9   4.3 | -10.1  13.8  295  23 12   7.7   4.2
 18500  -9.3  15.3  305  22 11   7.8   4.3 |  -9.0  15.8  295  23 12   7.5   4.1
 18000  -8.1  17.4  310  22 11   7.9   4.4 |  -7.9  17.8  295  23 12   7.8   4.3
 17500  -6.9  19.6  310  22 11   8.2   4.5 |  -6.7  19.9  300  23 12   8.2   4.5
 17000  -5.7  21.7  310  22 11   8.2   4.5 |  -5.5  22.1  300  22 11   8.2   4.5
 16500  -3.8  25.2  315  20 10   8.5   4.6 |  -4.3  24.3  305  22 11   8.8   4.8
 16000  -2.6  27.3  315  19 10   8.5   4.7 |  -2.4  27.7  305  20 11   8.8   4.8
 15500  -1.3  29.7  315  18  9   9.1   5.0 |  -1.1  30.0  310  20 10   8.8   4.8
 15000   0.1  32.2  315  17  9   9.0   5.0 |   0.2  32.4  310  19 10   8.9   4.9
 14500   1.4  34.5  320  16  8   9.0   4.9 |   1.5  34.7  315  18  9   8.7   4.8
 14000   2.7  36.9  320  14  7   8.9   4.9 |   2.8  37.0  315  17  9   8.7   4.8
 13500   4.1  39.4  325  13  7   9.3   5.1 |   4.1  39.4  320  16  8   8.9   4.9
 13000   5.5  41.9  325  13  6   9.4   5.2 |   5.4  41.7  320  16  8   9.0   4.9
 12500   6.9  44.4  330  12  6   9.3   5.1 |   6.7  44.1  320  15  8   9.2   5.0
 12000   8.2  46.8  330  12  6   9.2   5.1 |   8.1  46.6  325  15  8   9.3   5.1
 11500   9.6  49.3  335  13  7   9.2   5.1 |   9.4  48.9  325  15  8   9.1   5.0
 11000  11.0  51.8  335  13  6   8.9   4.9 |  10.8  51.4  325  13  7   8.6   4.7
 10500  12.4  54.3  335  12  6   4.2   2.3 |  12.1  53.8  325  12  6   3.5   1.9
 10250  12.5  54.5  335  13  6   5.8   3.2 |  12.2  54.0  325  12  6   5.6   3.0
 10000  13.3  55.9  330  13  7  13.3   7.3 |  13.1  55.6  330  11  6  13.6   7.4
  9750  14.2  57.6  330  13  7  11.9   6.5 |  13.9  57.0  330  11  6  11.9   6.5
  9500  15.1  59.2  330  13  7   8.9   4.9 |  14.8  58.6  330  11  5   9.2   5.0
  9250  15.6  60.1  330  14  7   6.2   3.4 |  15.3  59.5  335  11  5   6.7   3.7
  9000  16.1  61.0  330  14  7   9.5   5.2 |  15.9  60.6  335  11  5   9.4   5.2
  8750  16.9  62.4  330  14  7  10.5   5.8 |  16.7  62.1  335  10  5  10.0   5.5
  8500  17.7  63.9  330  14  7   9.3   5.1 |  17.4  63.3  340  10  5   9.0   4.9
  8250  18.3  64.9  330  14  7   9.0   4.9 |  18.0  64.4  340  10  5   8.3   4.6
  8000  19.0  66.2  330  14  7   8.6   4.7 |  18.6  65.5  340  10  5   9.0   4.9
  7750  19.6  67.3  325  14  7   8.0   4.4 |  19.3  66.7  340   9  5   9.6   5.2
  7500  20.2  68.4  325  15  8   8.4   4.6 |  20.0  68.0  340   8  4   9.3   5.1
  7250  20.8  69.4  320  15  8   8.4   4.6 |  20.7  69.3  340   7  4   9.4   5.1
  7000  21.4  70.5  320  15  8   9.0   4.9 |  21.4  70.5  340   6  3   8.9   4.9
  6750  22.0  71.6  315  16  8   5.9   3.3 |  22.0  71.6  340   5  3   9.5   5.2
  6500  22.2  72.0  315  16  8   1.3   0.7 |  22.8  73.0  340   5  3  10.7   5.9
  6250  22.4  72.3  310  15  8   5.0   2.8 |  23.5  74.3  345   5  3  10.5   5.8
  6000  22.5  72.5  305  15  8  -7.6  -4.2 |  24.3  75.7  345   5  2  10.8   5.9
  5750  21.0  69.8  295  12  6 -21.7 -11.9 |  25.2  77.4  345   5  2  14.3   7.9
  5500  19.7  67.5  275   7  4  -7.7  -4.2 |  26.5  79.7  345   5  2  19.3  10.6

           09/16/2014 at 1500 MDT          |       09/16/2014 at 1800 MDT
                                           |
K index... +14.8  LI... -1.1               | K index... +21.9  LI... -1.4
CAPE... +24.8  CIN... -47.6                | CAPE... +40.0  CIN... -68.7
                                           |
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 -65.8 -86.4  295  51 26   2.0   1.1 | -66.5 -87.7  300  53 27   2.1   1.2
 45000 -61.9 -79.4  295  62 32   4.1   2.3 | -61.8 -79.2  295  65 33   5.5   3.0
 40000 -55.3 -67.5  295  53 27   7.2   4.0 | -53.6 -64.5  290  58 30   5.7   3.2
 38000 -51.1 -60.0  295  50 26   7.1   3.9 | -50.1 -58.2  295  51 26   5.7   3.1
 36000 -46.8 -52.2  300  47 24   7.1   3.9 | -46.7 -52.1  295  44 23   5.7   3.1
 34000 -41.7 -43.1  305  42 22   7.7   4.2 | -41.5 -42.7  300  40 21   8.2   4.5
 32000 -37.0 -34.6  305  38 20   7.6   4.2 | -36.5 -33.7  300  38 20   8.1   4.5
 30000 -32.1 -25.8  300  36 18   8.3   4.5 | -31.6 -24.9  300  36 19   8.3   4.5
 29000 -29.6 -21.3  300  35 18   8.3   4.5 | -29.1 -20.4  300  36 18   8.3   4.5
 28000 -27.2 -17.0  295  34 17   7.8   4.3 | -26.6 -15.9  300  35 18   7.4   4.1
 27000 -24.9 -12.8  300  32 16   7.6   4.1 | -24.5 -12.1  300  34 18   7.0   3.9
 26000 -22.6  -8.7  300  30 15   7.6   4.1 | -22.4  -8.3  305  33 17   7.0   3.9
 25000 -20.4  -4.7  300  28 14   7.5   4.1 | -20.3  -4.5  305  32 17   7.1   3.9
 24000 -18.3  -0.9  300  26 13   6.9   3.8 | -18.2  -0.8  305  30 15   7.1   3.9
 23000 -16.2   2.8  300  24 13   6.9   3.8 | -16.1   3.0  305  28 14   7.1   3.9
 22000 -14.1   6.6  305  23 12   6.4   3.5 | -14.0   6.8  300  25 13   6.7   3.7
 21000 -12.6   9.3  305  22 11   4.8   2.6 | -12.4   9.7  305  25 13   5.2   2.8
 20000 -11.2  11.8  310  22 11   4.8   2.6 | -10.9  12.4  305  26 13   5.2   2.8
 19500 -10.5  13.1  310  22 11   4.4   2.4 | -10.1  13.8  305  26 13   4.9   2.7
 19000  -9.5  14.9  310  22 11   8.6   4.7 |  -9.2  15.4  305  26 13   9.1   5.0
 18500  -8.3  17.1  310  22 12   8.5   4.7 |  -7.9  17.8  305  25 13   9.1   5.0
 18000  -7.0  19.4  310  23 12   8.6   4.7 |  -6.6  20.1  305  24 12   9.0   4.9
 17500  -5.8  21.6  310  22 12   8.7   4.8 |  -5.3  22.5  305  23 12   8.7   4.8
 17000  -3.8  25.2  305  22 11   8.9   4.9 |  -4.1  24.6  305  22 11   8.7   4.8
 16500  -2.5  27.5  305  21 11   9.0   4.9 |  -2.1  28.2  300  20 10   8.9   4.9
 16000  -1.2  29.8  305  21 11   9.0   5.0 |  -0.8  30.6  300  20 10   8.9   4.9
 15500   0.2  32.4  300  20 10   9.0   4.9 |   0.5  32.9  300  19 10   8.4   4.6
 15000   1.5  34.7  300  19 10   9.1   5.0 |   1.7  35.1  300  18  9   8.5   4.7
 14500   2.7  36.9  300  18  9   8.2   4.5 |   2.9  37.2  300  16  8   8.2   4.5
 14000   3.9  39.0  300  17  9   8.2   4.5 |   4.1  39.4  300  14  7   8.2   4.5
 13500   5.0  41.0  300  16  8   8.0   4.4 |   5.3  41.5  300  12  6   7.7   4.2
 13000   6.1  43.0  305  14  7   8.0   4.4 |   6.4  43.5  300   8  4   7.5   4.1
 12500   7.3  45.1  305  12  6   8.3   4.6 |   7.5  45.5  295   4  2   7.5   4.1
 12000   8.5  47.3  310   9  5   8.6   4.7 |   8.6  47.5  275   2  1   7.6   4.1
 11500   9.8  49.6  315   7  4   8.4   4.6 |   9.7  49.5  160   2  1   8.1   4.5
 11000  11.0  51.8  330   5  2   7.9   4.3 |  11.0  51.8  135   2  1   8.8   4.8
 10500  12.2  54.0  005   3  1   4.5   2.5 |  12.4  54.3  115   3  1   4.9   2.7
 10250  12.4  54.3  005   3  1   6.2   3.4 |  12.6  54.7  115   3  1   6.2   3.4
 10000  13.2  55.8  015   3  1  11.9   6.5 |  13.4  56.1  110   3  1  12.3   6.7
  9750  14.0  57.2  025   3  1  10.9   6.0 |  14.2  57.6  105   3  1  11.1   6.1
  9500  14.8  58.6  035   3  1   9.3   5.1 |  15.1  59.2  105   3  1   9.7   5.3
  9250  15.4  59.7  030   3  1   7.9   4.3 |  15.7  60.3  100   3  1   8.1   4.4
  9000  16.1  61.0  030   3  1  10.4   5.7 |  16.3  61.3  095   3  1  10.0   5.5
  8750  16.9  62.4  030   3  1  11.2   6.1 |  17.1  62.8  095   3  1  10.6   5.8
  8500  17.7  63.9  030   3  1  10.4   5.7 |  17.9  64.2  095   3  1  10.0   5.5
  8250  18.4  65.1  035   3  1  10.0   5.5 |  18.6  65.5  090   3  1   9.7   5.3
  8000  19.2  66.6  035   3  1  10.1   5.5 |  19.3  66.7  085   3  1   9.7   5.3
  7750  19.9  67.8  035   3  1  10.0   5.5 |  20.1  68.2  080   3  1   9.6   5.3
  7500  20.7  69.3  035   3  1   9.9   5.5 |  20.8  69.4  080   3  1   9.8   5.4
  7250  21.4  70.5  035   3  1   9.8   5.4 |  21.5  70.7  075   3  1   9.9   5.4
  7000  22.1  71.8  035   3  1  10.1   5.5 |  22.3  72.1  070   3  1   9.8   5.4
  6750  22.9  73.2  035   3  1  10.5   5.7 |  23.0  73.4  070   3  1   9.9   5.4
  6500  23.7  74.7  035   3  1  10.3   5.7 |  23.7  74.7  070   3  1  10.0   5.5
  6250  24.5  76.1  035   3  1  10.5   5.8 |  24.5  76.1  065   3  1  10.3   5.6
  6000  25.3  77.5  035   2  1   9.6   5.3 |  25.2  77.4  065   2  1   9.4   5.1
  5750  26.1  79.0  030   3  1  13.3   7.3 |  25.9  78.6  060   2  1   9.1   5.0
  5500  27.4  81.3  035   3  1  22.2  12.2 |  26.6  79.9  060   2  1  11.4   6.2
________________________________________________________________________________

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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