Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 300159
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1959 MDT Monday, September 29, 2014

This forecast is for Tuesday, September 30, 2014:

If the trigger temperature of 62.9 F/17.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 829 ft/min (4.2 m/s)
   Maximum height of thermals.................. 14983 ft MSL (9696 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1200 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................. 9885 ft MSL (4597 ft AGL)
Thermal soaring outlook for Wednesday 10/01.... Poor

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....................... 23742 ft MSL (18455 ft AGL)
Wave soaring outlook for Wednesday 10/01....... Poor

Remarks...

Sunrise/Sunset.................... 06:54:47 / 18:45:00 MDT
Total possible sunshine........... 11 hr 50 min 13 sec (710 min 13 sec)
Altitude of sun at 12:49:23 MDT... 47.26 degrees

Upper air data from numerical model forecast valid on 09/30/2014 at 0600 MDT

Freezing level.................. 12285 ft MSL (6998 ft AGL)
Convective condensation level... 14328 ft MSL (9041 ft AGL)
Lifted condensation level....... 14550 ft MSL (9263 ft AGL)
Lifted index.................... -0.3
K index......................... +12.6

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  -58.7 -73.7   270   29   15   3.2   1.8      M     M       M      M    M
 45000  -53.6 -64.5   275   42   22   3.5   1.9      M     M       M      M    M
 40000  -48.2 -54.8   280   45   23   3.5   1.9      M     M       M      M    M
 38000  -46.6 -51.9   280   43   22   2.5   1.4      M     M       M      M    M
 36000  -45.1 -49.2   285   39   20   2.5   1.4      M     M       M      M    M
 34000  -43.7 -46.7   290   32   16   1.9   1.0      M     M       M      M    M
 32000  -42.6 -44.7   320   15    8   1.9   1.0      M     M       M      M    M
 30000  -40.1 -40.2   015   10    5   7.3   4.0   35.5  95.9    10.4      M    M
 29000  -38.0 -36.4   350    9    4   7.2   4.0   34.4  94.0     9.8      M    M
 28000  -35.8 -32.4   325    9    4   7.2   4.0   33.5  92.4     9.2      M    M
 27000  -33.6 -28.5   300   11    6   7.7   4.2   32.7  90.9     8.6      M    M
 26000  -31.3 -24.3   295   18    9   7.7   4.2   31.8  89.3     8.0      M    M
 25000  -29.0 -20.2   290   25   13   7.7   4.2   31.1  87.9     7.5      M    M
 24000  -26.7 -16.1   285   32   16   7.8   4.3   30.4  86.7     7.1      M    M
 23000  -24.3 -11.7   285   31   16   7.9   4.3   29.6  85.3     6.5      M    M
 22000  -21.9  -7.4   285   31   16   7.9   4.3   29.0  84.2     6.0      M    M
 21000  -19.6  -3.3   280   30   16   7.4   4.0   28.3  83.0     5.5      M    M
 20000  -17.5   0.5   280   29   15   7.3   4.0   27.4  81.3     4.8      M    M
 19500  -16.4   2.5   280   29   15   7.3   4.0   27.0  80.6     4.4      M    M
 19000  -15.3   4.5   280   28   14   7.3   4.0   26.6  79.9     4.1      M    M
 18500  -14.2   6.4   275   27   14   6.6   3.6   26.2  79.2     3.8      M    M
 18000  -13.3   8.1   275   26   13   6.2   3.4   25.6  78.0     3.2      M    M
 17500  -12.4   9.7   270   24   12   6.1   3.4   24.9  76.9     2.7      M    M
 17000  -11.5  11.3   265   22   11   6.4   3.5   24.3  75.8     2.2      M    M
 16500  -10.6  12.9   265   20   10   6.4   3.5   23.8  74.8     1.6      M    M
 16000   -9.6  14.7   265   17    9   6.4   3.5   23.2  73.8     1.1      M    M
 15500   -8.7  16.3   265   13    7   6.5   3.6   22.6  72.7     0.6      M    M
 15000   -7.2  19.0   265    9    5   8.2   4.5   21.9  71.5    -0.1    819  4.2
 14500   -5.9  21.4   270    6    3   8.2   4.5   21.7  71.0    -0.3    768  3.9
 14000   -4.7  23.5   280    4    2   9.1   5.0   21.5  70.6    -0.5    715  3.6
 13500   -3.3  26.1   290    4    2   9.4   5.2   21.4  70.5    -0.5    658  3.3
 13000   -1.8  28.8   300    4    2   9.4   5.2   21.4  70.5    -0.6    600  3.0
 12500   -0.4  31.3   315    8    4   9.3   5.1   21.3  70.3    -0.6    543  2.8
 12000    1.0  33.8   320   11    6   8.5   4.6   21.3  70.3    -0.6    485  2.5
 11500    2.1  35.8   315   17    9   7.3   4.0   20.9  69.5    -1.1    438  2.2
 11000    3.1  37.6   315   23   12   6.4   3.5   20.5  68.9    -1.5    392  2.0
 10500    3.9  39.0   305   28   15   4.7   2.6   19.8  67.6    -2.2    356  1.8
 10250    4.2  39.6   305   31   16   6.5   3.6   19.4  66.9    -2.6    338  1.7
 10000    4.7  40.5   300   34   18   5.6   3.1   19.2  66.5    -2.8    315  1.6
  9750    4.9  40.8   300   36   18   2.7   1.5   18.7  65.6    -3.4    301  1.5
  9500    5.1  41.2   295   37   19   2.9   1.6   18.1  64.6    -3.9    288  1.5
  9250    5.3  41.5   295   38   20   3.4   1.8   17.6  63.7    -4.5    275  1.4
  9000    5.6  42.1   290   38   20   3.8   2.1   17.2  62.9    -5.0    261  1.3
  8750    5.8  42.4   290   36   19   3.6   2.0   16.7  62.0    -5.5    246  1.2
  8500    6.0  42.8   290   34   18   3.5   1.9   16.2  61.1    -6.0    231  1.2
  8250    6.3  43.3   285   32   16   4.4   2.4   15.7  60.3    -6.5    217  1.1
  8000    6.7  44.1   285   29   15   7.1   3.9   15.4  59.8    -6.8    197  1.0
  7750    7.2  45.0   285   26   14   7.3   4.0   15.3  59.5    -7.0    173  0.9
  7500    7.7  45.9   285   24   12   6.2   3.4   15.0  59.0    -7.3    151  0.8
  7250    8.2  46.8   285   22   11   7.3   4.0   14.8  58.6    -7.5    129  0.7
  7000    8.8  47.8   280   20   10   8.3   4.5   14.6  58.3    -7.7    104  0.5
  6750    9.4  48.9   280   17    9   7.5   4.1   14.5  58.1    -7.8     79  0.4
  6500    9.9  49.8   275   15    8   6.8   3.7   14.3  57.7    -8.1     56  0.3
  6250   10.4  50.7   270   14    7   5.4   2.9   14.0  57.2    -8.4     35  0.2
  6000   10.7  51.3   265   12    6   4.2   2.3   13.6  56.5    -8.8     19  0.1
  5750   10.9  51.6   250   10    5   2.7   1.5   13.2  55.7    -9.3      4  0.0
  5500   10.8  51.4   230    9    4  -5.9  -3.2   12.4  54.3   -10.2      1  0.0

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

           09/30/2014 at 0900 MDT          |       09/30/2014 at 1200 MDT
                                           |
K index... +13.7  LI... +2.9               | K index... +15.4  LI... +1.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -58.8 -73.8  275  30 15   3.6   2.0 | -58.9 -74.0  250  23 12   3.1   1.7
 45000 -53.5 -64.3  280  46 24   2.1   1.1 | -54.5 -66.1  255  34 17   1.3   0.7
 40000 -50.4 -58.7  285  49 25   2.1   1.1 | -52.5 -62.5  280  46 23   1.2   0.7
 38000 -48.7 -55.7  290  48 25   2.9   1.6 | -50.7 -59.3  280  49 25   3.3   1.8
 36000 -47.0 -52.6  290  46 24   2.9   1.6 | -48.7 -55.7  280  53 27   3.3   1.8
 34000 -44.8 -48.6  290  42 22   4.8   2.6 | -45.8 -50.4  280  55 29   7.2   3.9
 32000 -41.9 -43.4  285  32 17   4.8   2.6 | -41.6 -42.9  285  57 29   7.1   3.9
 30000 -37.9 -36.2  280  25 13   7.9   4.3 | -36.4 -33.5  285  58 30   8.3   4.5
 29000 -35.5 -31.9  280  23 12   7.9   4.3 | -34.0 -29.2  285  58 30   8.3   4.5
 28000 -33.2 -27.8  275  22 11   7.9   4.3 | -31.5 -24.7  285  58 30   8.3   4.5
 27000 -30.9 -23.6  275  22 11   5.6   3.1 | -29.2 -20.6  290  57 29   6.8   3.7
 26000 -29.2 -20.6  275  26 14   5.9   3.2 | -27.1 -16.8  290  55 28   6.9   3.8
 25000 -27.4 -17.3  280  31 16   5.9   3.2 | -25.0 -13.0  285  53 28   6.9   3.8
 24000 -25.6 -14.1  280  35 18   6.8   3.7 | -23.0  -9.4  285  51 26   5.7   3.1
 23000 -23.5 -10.3  280  34 18   7.2   3.9 | -21.4  -6.5  280  45 23   5.5   3.0
 22000 -21.4  -6.5  275  34 17   7.3   4.0 | -19.7  -3.5  275  40 21   5.5   3.0
 21000 -19.2  -2.6  275  33 17   7.3   4.0 | -18.1  -0.6  265  36 18   5.8   3.2
 20000 -17.0   1.4  275  30 15   7.3   4.0 | -16.4   2.5  260  33 17   5.8   3.2
 19500 -16.0   3.2  275  28 15   7.3   4.0 | -15.5   4.1  255  32 16   5.9   3.2
 19000 -14.9   5.2  275  27 14   7.3   4.0 | -14.6   5.7  255  30 16   5.9   3.2
 18500 -13.8   7.2  275  25 13   6.7   3.7 | -13.8   7.2  250  29 15   6.1   3.4
 18000 -12.8   9.0  275  23 12   6.4   3.5 | -12.9   8.8  250  27 14   6.2   3.4
 17500 -11.9  10.6  275  20 10   6.4   3.5 | -12.0  10.4  250  24 12   6.2   3.4
 17000 -11.0  12.2  280  18  9   5.8   3.2 | -11.1  12.0  255  22 11   6.1   3.3
 16500 -10.1  13.8  285  16  8   5.9   3.2 | -10.2  13.6  255  19 10   6.0   3.3
 16000  -9.3  15.3  285  13  7   5.9   3.2 |  -9.3  15.3  255  17  9   6.8   3.7
 15500  -8.4  16.9  290  10  5   6.0   3.3 |  -8.3  17.1  255  14  7   6.9   3.8
 15000  -6.9  19.6  295   7  3   8.2   4.5 |  -6.6  20.1  265  11  5   8.4   4.6
 14500  -5.8  21.6  305   5  3   7.9   4.3 |  -5.4  22.3  270  10  5   8.2   4.5
 14000  -4.5  23.9  320   4  2   9.2   5.0 |  -4.2  24.4  275   9  5   9.1   5.0
 13500  -3.1  26.4  330   4  2   9.4   5.1 |  -2.8  27.0  290  11  6   9.2   5.1
 13000  -1.7  28.9  340   4  2   9.7   5.3 |  -1.5  29.3  295  13  7   8.0   4.4
 12500  -0.3  31.5  340   5  3   9.8   5.4 |  -0.3  31.5  300  17  9   7.5   4.1
 12000   1.2  34.2  335   6  3   8.8   4.8 |   0.7  33.3  300  21 11   6.8   3.7
 11500   2.3  36.1  325  12  6   7.8   4.3 |   1.6  34.9  300  24 13   6.3   3.5
 11000   3.4  38.1  320  18  9   6.5   3.6 |   2.5  36.5  300  28 14   5.1   2.8
 10500   4.2  39.6  315  23 12   4.6   2.5 |   3.1  37.6  295  29 15   3.8   2.1
 10250   4.5  40.1  315  25 13   7.5   4.1 |   3.4  38.1  295  29 15   5.8   3.2
 10000   5.1  41.2  310  28 14   5.8   3.2 |   3.9  39.0  295  28 15   6.2   3.4
  9750   5.3  41.5  305  29 15   1.6   0.9 |   4.2  39.6  295  26 13   4.5   2.5
  9500   5.5  41.9  305  31 16   2.8   1.5 |   4.5  40.1  290  23 12   4.6   2.5
  9250   5.6  42.1  300  33 17   2.3   1.3 |   4.9  40.8  290  20 10   5.9   3.2
  9000   5.8  42.4  300  33 17   2.0   1.1 |   5.4  41.7  285  18  9   8.2   4.5
  8750   5.9  42.6  300  31 16   2.1   1.1 |   6.0  42.8  285  15  8   8.7   4.8
  8500   6.0  42.8  295  29 15   1.7   0.9 |   6.6  43.9  280  13  7   8.3   4.5
  8250   6.1  43.0  295  28 14   3.3   1.8 |   7.2  45.0  275  11  6   9.5   5.2
  8000   6.5  43.7  295  25 13   6.7   3.7 |   8.0  46.4  275  10  5  10.6   5.8
  7750   7.0  44.6  290  22 11   6.8   3.8 |   8.8  47.8  270   9  5   9.6   5.3
  7500   7.5  45.5  290  20 10   5.7   3.1 |   9.5  49.1  270   9  5   9.0   4.9
  7250   7.9  46.2  290  17  9   7.2   4.0 |  10.2  50.4  270   9  4  10.2   5.6
  7000   8.5  47.3  290  15  8   8.6   4.7 |  11.0  51.8  270   8  4  11.0   6.0
  6750   9.2  48.6  285  12  6   7.8   4.3 |  11.7  53.1  270   8  4   9.2   5.1
  6500   9.7  49.5  280  11  5   7.3   4.0 |  12.4  54.3  270   8  4   9.1   5.0
  6250  10.2  50.4  275   9  4   6.6   3.6 |  13.1  55.6  265   7  4  10.8   5.9
  6000  10.7  51.3  260   7  3   6.4   3.5 |  14.0  57.2  265   7  4  11.8   6.5
  5750  11.1  52.0  240   5  3   5.7   3.1 |  14.8  58.6  265   7  4   9.7   5.3
  5500  11.4  52.5  210   5  2   6.8   3.7 |  15.5  59.9  265   6  3  12.5   6.9

           09/30/2014 at 1500 MDT          |       09/30/2014 at 1800 MDT
                                           |
K index... +17.5  LI... +0.9               | K index... +24.1  LI... -1.2
CAPE... 0.0  CIN... -0.6                   | CAPE... +37.2  CIN... -33.9
                                           |
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 -59.9 -75.8  245  22 11   2.2   1.2 | -59.0 -74.2  250  21 11   1.8   1.0
 45000 -56.4 -69.5  255  30 15   3.0   1.6 | -56.1 -69.0  255  27 14   2.9   1.6
 40000 -51.7 -61.1  270  49 25   3.1   1.7 | -51.5 -60.7  265  52 27   3.0   1.6
 38000 -50.5 -58.9  270  52 27   1.7   0.9 | -50.4 -58.7  260  54 28   1.5   0.8
 36000 -49.5 -57.1  270  53 27   1.7   0.9 | -49.5 -57.1  260  54 28   1.5   0.8
 34000 -46.9 -52.4  270  54 28   8.1   4.5 | -47.1 -52.8  255  54 28   8.0   4.4
 32000 -42.1 -43.8  270  52 27   8.1   4.4 | -42.3 -44.1  255  55 28   7.9   4.4
 30000 -37.2 -35.0  265  49 25   8.3   4.5 | -37.4 -35.3  255  54 28   8.6   4.7
 29000 -34.1 -29.4  265  47 24   8.3   4.5 | -34.2 -29.6  255  51 26   8.6   4.7
 28000 -31.6 -24.9  265  45 23   8.3   4.5 | -31.7 -25.1  255  48 25   8.6   4.7
 27000 -29.2 -20.6  265  43 22   7.5   4.1 | -29.3 -20.7  255  45 23   7.0   3.8
 26000 -27.0 -16.6  265  42 22   7.5   4.1 | -27.2 -17.0  255  40 21   7.1   3.9
 25000 -24.8 -12.6  265  41 21   7.6   4.1 | -25.1 -13.2  255  35 18   7.1   3.9
 24000 -22.7  -8.9  265  39 20   5.7   3.1 | -23.1  -9.6  255  30 16   5.6   3.1
 23000 -21.0  -5.8  265  37 19   5.5   3.0 | -21.5  -6.7  255  29 15   5.5   3.0
 22000 -19.4  -2.9  265  34 18   5.5   3.0 | -19.9  -3.8  260  28 15   5.5   3.0
 21000 -17.7   0.1  260  32 16   6.3   3.5 | -18.2  -0.8  260  27 14   5.8   3.2
 20000 -15.8   3.6  260  31 16   6.2   3.4 | -16.5   2.3  260  25 13   5.8   3.2
 19500 -14.9   5.2  255  30 15   6.2   3.4 | -15.7   3.7  260  23 12   5.8   3.2
 19000 -13.9   7.0  255  29 15   6.2   3.4 | -14.8   5.4  260  22 11   5.7   3.1
 18500 -13.0   8.6  255  28 15   5.8   3.2 | -13.9   7.0  260  21 11   6.9   3.8
 18000 -12.2  10.0  255  26 13   5.7   3.1 | -12.9   8.8  260  21 11   7.2   3.9
 17500 -11.4  11.5  255  24 12   5.7   3.1 | -11.8  10.8  265  21 11   7.3   4.0
 17000 -10.5  13.1  255  22 11   5.6   3.0 | -10.7  12.7  265  21 11   7.7   4.2
 16500  -9.7  14.5  255  20 10   5.4   2.9 |  -9.6  14.7  270  21 11   7.7   4.2
 16000  -8.8  16.2  260  19 10   8.3   4.5 |  -8.5  16.7  270  22 11   7.5   4.1
 15500  -7.5  18.5  265  20 10   8.4   4.6 |  -7.4  18.7  270  22 11   7.5   4.1
 15000  -6.3  20.7  270  20 10   8.0   4.4 |  -6.3  20.7  275  22 11   7.4   4.1
 14500  -4.6  23.7  275  23 12   7.7   4.2 |  -4.7  23.5  270  21 11   7.3   4.0
 14000  -3.5  25.7  280  26 13   7.5   4.1 |  -3.6  25.5  270  20 10   8.2   4.5
 13500  -2.4  27.7  285  27 14   7.5   4.1 |  -2.4  27.7  265  19 10   8.3   4.6
 13000  -1.4  29.5  285  29 15   7.3   4.0 |  -1.2  29.8  265  17  9   8.2   4.5
 12500  -0.3  31.5  285  28 15   7.3   4.0 |   0.0  32.0  265  16  8   8.2   4.5
 12000   0.7  33.3  285  27 14   7.4   4.0 |   1.3  34.3  260  14  7   8.8   4.8
 11500   1.8  35.2  280  24 12   7.4   4.1 |   2.6  36.7  255  12  6   9.1   5.0
 11000   2.8  37.0  280  20 10   6.9   3.8 |   4.0  39.2  250  11  6   8.5   4.7
 10500   3.8  38.8  275  16  8   6.1   3.3 |   5.2  41.4  245  10  5   7.6   4.2
 10250   4.3  39.7  270  14  7   8.5   4.7 |   5.8  42.4  240   9  5   9.5   5.2
 10000   5.0  41.0  270  12  6   9.2   5.0 |   6.5  43.7  230   9  4  10.0   5.5
  9750   5.6  42.1  265  10  5   7.2   3.9 |   7.2  45.0  225   8  4   8.3   4.6
  9500   6.1  43.0  255   8  4   7.6   4.1 |   7.8  46.0  220   8  4   9.0   5.0
  9250   6.7  44.1  245   6  3   8.0   4.4 |   8.5  47.3  215   8  4   7.8   4.3
  9000   7.3  45.1  235   6  3   9.3   5.1 |   9.0  48.2  210   8  4   7.4   4.0
  8750   8.0  46.4  235   5  3   9.8   5.4 |   9.6  49.3  200   8  4   8.2   4.5
  8500   8.7  47.7  230   5  3   9.4   5.2 |  10.2  50.4  195   7  4   7.8   4.3
  8250   9.5  49.1  225   5  3  10.4   5.7 |  10.8  51.4  185   7  4   8.5   4.6
  8000  10.3  50.5  225   5  3  10.5   5.7 |  11.4  52.5  180   6  3   8.9   4.9
  7750  11.0  51.8  225   5  2   9.2   5.1 |  12.1  53.8  175   6  3   8.6   4.7
  7500  11.6  52.9  225   5  2   8.6   4.7 |  12.7  54.9  170   5  3   8.2   4.5
  7250  12.3  54.1  225   5  2  10.3   5.7 |  13.3  55.9  170   5  2   9.3   5.1
  7000  13.2  55.8  220   5  2  11.6   6.4 |  14.0  57.2  165   4  2  10.2   5.6
  6750  14.0  57.2  220   5  2   9.5   5.2 |  14.8  58.6  165   4  2   9.2   5.0
  6500  14.6  58.3  220   5  2   9.0   4.9 |  15.4  59.7  165   4  2   8.8   4.8
  6250  15.4  59.7  220   4  2  10.6   5.8 |  16.1  61.0  165   3  2  10.0   5.5
  6000  16.2  61.2  220   4  2  11.8   6.5 |  16.9  62.4  165   3  2  10.8   5.9
  5750  17.0  62.6  215   4  2   9.9   5.5 |  17.6  63.7  170   3  1   9.5   5.2
  5500  17.8  64.0  215   4  2  12.9   7.1 |  18.3  64.9  170   2  1   8.6   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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