Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151243
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0642 MDT Monday, September 15, 2014

This forecast is for Monday, September 15, 2014:

If the trigger temperature of 66.2 F/19.0 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 254 ft/min (1.3 m/s)
   Maximum height of thermals.................. 9325 ft MSL (4040 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1345 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................. 8307 ft MSL (3022 ft AGL)
Thermal soaring outlook for Tuesday 09/16...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 18084 ft MSL (12799 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 42205 ft MSL (36920 ft AGL)
Wave soaring outlook for Tuesday 09/16......... Poor

Remarks...

Sunrise/Sunset.................... 06:40:32 / 19:09:34 MDT
Total possible sunshine........... 12 hr 29 min 1 sec (749 min 1 sec)
Altitude of sun at 12:54:34 MDT... 53.07 degrees

Upper air data from rawinsonde observation taken on 09/15/2014 at 0600 MDT

Freezing level.................. 14589 ft MSL (9304 ft AGL)
Convective condensation level... 14605 ft MSL (9320 ft AGL)
Lifted condensation level....... 11478 ft MSL (6193 ft AGL)
Lifted index.................... +2.0
K index......................... +20.8

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  -65.2 -85.4   285   64   33  -1.4  -0.8   87.0 188.6    38.7      M    M
 45000  -59.9 -75.8   275   66   34   4.8   2.6   69.9 157.7    31.0      M    M
 40000  -55.1 -67.2   270   69   35   3.0   1.6   54.9 130.8    23.2      M    M
 38000  -53.0 -63.4   270   67   35   7.8   4.3   49.3 120.7    20.0      M    M
 36000  -48.0 -54.4   275   65   34   8.4   4.6   48.1 118.5    19.7      M    M
 34000  -43.2 -45.8   275   59   30   7.9   4.3   46.6 115.9    19.1      M    M
 32000  -39.4 -38.9   275   51   26   5.5   3.0   43.7 110.7    17.5      M    M
 30000  -35.1 -31.2   280   42   22   7.6   4.1   40.8 105.4    15.7      M    M
 29000  -33.3 -27.9   280   40   21   0.0   0.0   39.3 102.8    14.8      M    M
 28000  -31.2 -24.2   280   38   20   9.8   5.4   38.2 100.8    14.1      M    M
 27000  -28.3 -18.9   280   37   19   9.7   5.3   38.2 100.8    14.3      M    M
 26000  -25.6 -14.1   280   35   18   7.2   4.0   38.0 100.4    14.3      M    M
 25000  -23.1  -9.6   280   33   17   8.4   4.6   37.4  99.4    14.0      M    M
 24000  -20.9  -5.6   285   32   16   6.2   3.4   36.6  97.9    13.5      M    M
 23000  -18.5  -1.3   290   28   14   3.8   2.1   35.8  96.5    13.0      M    M
 22000  -17.3   0.9   280   24   12   6.9   3.8   33.9  93.0    11.5      M    M
 21000  -15.0   5.0   295   21   11   7.8   4.3   33.1  91.6    11.0      M    M
 20000  -12.6   9.3   295   20   10   8.2   4.5   32.4  90.4    10.5      M    M
 19500  -11.3  11.7   300   20   10   9.0   4.9   32.2  90.0    10.4      M    M
 19000  -10.2  13.6   300   19   10   6.7   3.7   31.8  89.3    10.1      M    M
 18500   -9.2  15.4   295   16    8   5.6   3.1   31.4  88.5     9.7      M    M
 18000   -9.4  15.1   285   13    7  -0.1  -0.1   29.7  85.4     8.1      M    M
 17500   -8.4  16.9   290   13    7   9.5   5.2   29.2  84.6     7.7      M    M
 17000   -7.0  19.4   290   13    7   9.3   5.1   29.2  84.5     7.7      M    M
 16500   -5.6  21.9   295   13    7   9.3   5.1   29.1  84.4     7.7      M    M
 16000   -4.3  24.3   300   13    7   9.3   5.1   29.1  84.4     7.7      M    M
 15500   -2.9  26.8   305   13    7   9.3   5.1   29.0  84.3     7.6      M    M
 15000   -0.8  30.6   310   13    7   9.3   5.1   28.9  84.1     7.6      M    M
 14500    0.5  32.9   305   11    6   9.3   5.1   28.8  83.9     7.5      M    M
 14000    1.9  35.4   305   10    5   9.3   5.1   28.8  83.8     7.5      M    M
 13500    3.3  37.9   310   11    5   9.3   5.1   28.6  83.5     7.4      M    M
 13000    4.7  40.5   310   11    6   9.3   5.1   28.5  83.3     7.3      M    M
 12500    6.0  42.8   315   12    6   9.2   5.1   28.4  83.2     7.2      M    M
 12000    7.4  45.3   315   12    6   8.9   4.9   28.3  83.0     7.2      M    M
 11500    8.6  47.5   305   13    7   8.1   4.4   28.1  82.5     6.9      M    M
 11000    9.8  49.6   300   14    7   8.1   4.4   27.8  82.1     6.7      M    M
 10500   10.9  51.6   295   15    8   7.4   4.1   27.6  81.6     6.4      M    M
 10250   11.4  52.5   295   14    7   4.8   2.6   27.3  81.1     6.2      M    M
 10000   11.6  52.9   295   13    7   2.6   1.4   26.8  80.3     5.7      M    M
  9750   11.8  53.2   305   12    6   6.2   3.4   26.3  79.4     5.2      M    M
  9500   10.9  51.6   315   12    6 -50.3 -27.6   24.7  76.4     3.5      M    M
  9250    5.7  42.3   325   12    6 -35.5 -19.5   18.8  65.8    -2.5    316  1.6
  9000    6.2  43.2   335   13    7  19.6  10.7   18.6  65.5    -2.6    291  1.5
  8750    6.8  44.2   345   11    6   4.6   2.5   18.5  65.2    -2.8    266  1.4
  8500    7.4  45.3   360   11    5   8.5   4.7   18.3  64.9    -2.9    241  1.2
  8250    8.0  46.4   015   10    5   7.9   4.3   18.1  64.7    -3.0    215  1.1
  8000    8.6  47.5   030   11    6   6.5   3.6   18.0  64.4    -3.2    190  1.0
  7750    9.0  48.2   035   11    6  -0.6  -0.3   17.5  63.5    -3.6    173  0.9
  7500    8.8  47.8   040   12    6  -4.1  -2.2   16.5  61.7    -4.4    169  0.9
  7250    8.5  47.3   040   12    6  -6.7  -3.7   15.4  59.7    -5.5    171  0.9
  7000    8.0  46.4   045   13    7   0.8   0.4   14.2  57.6    -6.8    179  0.9
  6750    8.6  47.5   040   11    6   9.2   5.0   14.1  57.3    -7.0    155  0.8
  6500    9.1  48.4   030    9    5   6.9   3.8   13.9  57.0    -7.2    132  0.7
  6250    9.6  49.3   015    7    4   7.5   4.1   13.7  56.7    -7.4    108  0.5
  6000   10.2  50.4   355    6    3   7.4   4.1   13.5  56.4    -7.6     84  0.4
  5750   10.7  51.3   355    4    2   7.3   4.0   13.3  56.0    -7.8     61  0.3
  5500   11.3  52.3   355    2    1   7.9   4.3   13.2  55.7    -8.0     37  0.2

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

           09/15/2014 at 0900 MDT          |       09/15/2014 at 1200 MDT
                                           |
K index... +17.0  LI... -2.2               | K index... +16.2  LI... -1.2
CAPE... +255.1  CIN... -218.3              | CAPE... +162.2  CIN... -282.2
                                           |
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 -63.8 -82.8  290  45 23   3.0   1.6 | -64.0 -83.2  285  40 21   2.4   1.3
 45000 -59.4 -74.9  285  58 30   2.6   1.4 | -60.1 -76.2  285  54 28   3.0   1.6
 40000 -55.3 -67.5  280  57 29   6.6   3.6 | -55.4 -67.7  285  57 29   7.2   4.0
 38000 -51.4 -60.5  280  57 29   6.5   3.6 | -51.2 -60.2  285  56 29   6.9   3.8
 36000 -47.5 -53.5  280  56 29   6.5   3.6 | -47.0 -52.6  285  54 28   6.9   3.8
 34000 -43.6 -46.5  280  51 26   6.4   3.5 | -42.9 -45.2  285  47 24   5.8   3.2
 32000 -39.3 -38.7  285  43 22   6.4   3.5 | -39.4 -38.9  285  39 20   5.7   3.2
 30000 -35.2 -31.4  285  35 18   7.0   3.8 | -35.4 -31.7  290  32 16   6.9   3.8
 29000 -33.1 -27.6  285  32 16   7.0   3.8 | -33.4 -28.1  290  29 15   6.9   3.8
 28000 -31.1 -24.0  285  28 15   7.5   4.1 | -31.3 -24.3  290  25 13   7.6   4.2
 27000 -28.6 -19.5  285  28 14   8.2   4.5 | -28.8 -19.8  290  26 13   8.4   4.6
 26000 -26.1 -15.0  285  28 14   8.3   4.5 | -26.3 -15.3  290  26 13   8.4   4.6
 25000 -23.7 -10.7  285  28 14   8.3   4.6 | -23.7 -10.7  285  26 14   8.5   4.7
 24000 -21.4  -6.5  285  26 14   7.6   4.1 | -21.5  -6.7  285  27 14   7.4   4.1
 23000 -19.1  -2.4  285  25 13   7.6   4.2 | -19.3  -2.7  285  27 14   7.5   4.1
 22000 -16.9   1.6  285  23 12   7.4   4.1 | -17.1   1.2  285  28 14   7.5   4.1
 21000 -15.0   5.0  280  20 10   6.0   3.3 | -15.0   5.0  290  25 13   6.9   3.8
 20000 -13.3   8.1  280  17  9   6.0   3.3 | -13.0   8.6  290  21 11   6.9   3.8
 19500 -12.4   9.7  275  15  8   5.8   3.2 | -11.9  10.6  290  20 10   6.9   3.8
 19000 -11.3  11.7  275  14  7   8.2   4.5 | -10.9  12.4  290  18  9   7.2   3.9
 18500 -10.1  13.8  275  14  7   8.2   4.5 |  -9.8  14.4  290  17  9   7.2   3.9
 18000  -8.9  16.0  275  14  7   8.2   4.5 |  -8.8  16.2  295  16  8   7.5   4.1
 17500  -7.7  18.1  280  14  7   8.0   4.4 |  -7.6  18.3  295  16  8   8.1   4.4
 17000  -6.5  20.3  280  14  7   8.0   4.4 |  -6.4  20.5  290  16  8   8.0   4.4
 16500  -5.3  22.5  280  14  7   8.7   4.8 |  -4.5  23.9  290  15  8   8.6   4.7
 16000  -3.3  26.1  285  14  7   8.6   4.7 |  -3.2  26.2  285  14  7   8.7   4.8
 15500  -2.0  28.4  290  14  7   9.0   5.0 |  -1.8  28.8  280  13  7   9.3   5.1
 15000  -0.7  30.7  290  14  7   9.0   4.9 |  -0.5  31.1  280  13  6   9.3   5.1
 14500   0.6  33.1  290  13  7   9.5   5.2 |   0.9  33.6  275  12  6   9.1   5.0
 14000   2.0  35.6  290  12  6   9.5   5.2 |   2.3  36.1  275  11  6   9.1   5.0
 13500   3.4  38.1  295  11  6   9.3   5.1 |   3.6  38.5  275  10  5   9.3   5.1
 13000   4.8  40.6  295  10  5   9.3   5.1 |   5.0  41.0  270   9  5   9.3   5.1
 12500   6.2  43.2  300   9  5   8.8   4.8 |   6.3  43.3  270   8  4   8.8   4.9
 12000   7.4  45.3  300   9  4   8.4   4.6 |   7.6  45.7  270   7  4   8.6   4.7
 11500   8.6  47.5  300   8  4   7.6   4.2 |   8.9  48.0  265   6  3   8.0   4.4
 11000   9.6  49.3  300   8  4   6.8   3.7 |  10.0  50.0  265   6  3   7.5   4.1
 10500  10.6  51.1  300   7  4   4.5   2.5 |  11.0  51.8  265   6  3   5.5   3.0
 10250  10.7  51.3  300   8  4   1.2   0.6 |  11.3  52.3  265   6  3   3.5   1.9
 10000  10.8  51.4  305   8  4   0.7   0.4 |  11.6  52.9  270   6  3   4.7   2.6
  9750  10.7  51.3  310   8  4   0.8   0.4 |  11.9  53.4  270   7  3   5.7   3.1
  9500  10.6  51.1  315   8  4  -4.8  -2.7 |  12.1  53.8  275   7  4  -4.8  -2.6
  9250   9.8  49.6  325   7  4  -9.4  -5.1 |  11.1  52.0  275   6  3 -11.4  -6.2
  9000   9.0  48.2  335   6  3  -9.4  -5.2 |  10.2  50.4  275   5  2 -14.3  -7.8
  8750   8.1  46.6  360   5  3  -8.8  -4.8 |   8.7  47.7  250   2  1 -16.8  -9.2
  8500   7.7  45.9  025   5  3   3.1   1.7 |   7.8  46.0  185   2  1  -1.5  -0.8
  8250   8.3  46.9  045   5  2   8.7   4.8 |   8.1  46.6  170   4  2   5.2   2.9
  8000   8.8  47.8  065   5  2   9.3   5.1 |   8.3  46.9  165   5  3   4.8   2.6
  7750   9.5  49.1  085   6  3   8.3   4.5 |   8.8  47.8  160   7  4   8.5   4.7
  7500   9.8  49.6  100   6  3   2.5   1.4 |   9.4  48.9  155   9  5   8.8   4.8
  7250  10.0  50.0  110   7  4   1.7   0.9 |  10.0  50.0  150  10  5   9.2   5.1
  7000  10.1  50.2  120   8  4   1.9   1.0 |  10.6  51.1  150  12  6   6.1   3.4
  6750  10.2  50.4  120   7  4  -1.0  -0.5 |  10.9  51.6  145  11  6   4.8   2.7
  6500  10.1  50.2  125   5  2  -2.4  -1.3 |  11.4  52.5  145   9  5   7.3   4.0
  6250   9.9  49.8  135   2  1  -3.6  -2.0 |  11.9  53.4  140   7  4   6.4   3.5
  6000   9.8  49.6  245   1  0   2.6   1.4 |  12.4  54.3  130   6  3   7.5   4.1
  5750  10.4  50.7  265   1  0  11.7   6.4 |  13.2  55.8  125   5  3  12.9   7.1
  5500  11.2  52.2  280   1  1   7.8   4.3 |  14.4  57.9  125   5  3  18.8  10.3

           09/15/2014 at 1500 MDT          |       09/15/2014 at 1800 MDT
                                           |
K index... +18.9  LI... -2.8               | K index... +23.7  LI... -4.2
CAPE... +414.5  CIN... -198.4              | CAPE... +823.5  CIN... -116.1
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.2 -83.6  280  40 21   2.5   1.4 | -64.4 -83.9  290  45 23   2.4   1.3
 45000 -60.3 -76.5  285  53 27   3.1   1.7 | -60.4 -76.7  290  58 30   3.5   1.9
 40000 -55.3 -67.5  285  54 28   7.4   4.0 | -54.9 -66.8  285  56 29   6.6   3.6
 38000 -51.2 -60.2  285  53 27   6.9   3.8 | -51.1 -60.0  290  55 28   6.3   3.5
 36000 -47.0 -52.6  285  52 27   6.9   3.8 | -47.3 -53.1  290  54 28   6.3   3.5
 34000 -42.6 -44.7  285  47 24   6.4   3.5 | -42.6 -44.7  290  51 26   7.2   3.9
 32000 -38.8 -37.8  285  41 21   6.4   3.5 | -38.3 -36.9  290  46 24   7.1   3.9
 30000 -34.8 -30.6  285  33 17   6.7   3.7 | -34.0 -29.2  290  41 21   7.2   3.9
 29000 -32.7 -26.9  285  29 15   6.7   3.7 | -31.8 -25.2  290  38 20   7.2   4.0
 28000 -30.7 -23.3  290  25 13   7.4   4.0 | -29.7 -21.5  290  35 18   7.4   4.1
 27000 -28.3 -18.9  290  25 13   8.1   4.5 | -27.4 -17.3  290  33 17   7.7   4.2
 26000 -25.8 -14.4  290  25 13   8.1   4.5 | -25.1 -13.2  290  31 16   7.7   4.2
 25000 -23.4 -10.1  290  25 13   8.2   4.5 | -22.8  -9.0  290  30 15   7.7   4.2
 24000 -21.3  -6.3  290  27 14   6.9   3.8 | -20.6  -5.1  290  29 15   7.1   3.9
 23000 -19.2  -2.6  290  30 16   7.0   3.8 | -18.5  -1.3  290  30 15   7.1   3.9
 22000 -17.2   1.0  290  33 17   7.2   3.9 | -16.4   2.5  290  30 16   7.2   3.9
 21000 -15.0   5.0  290  32 17   7.3   4.0 | -14.4   6.1  295  30 16   6.8   3.7
 20000 -12.9   8.8  295  30 15   7.3   4.0 | -12.4   9.7  295  30 15   6.8   3.7
 19500 -11.8  10.8  295  29 15   7.2   4.0 | -11.4  11.5  300  30 15   6.7   3.7
 19000 -10.7  12.7  295  28 14   8.5   4.6 | -10.3  13.5  300  29 15   8.5   4.7
 18500  -9.4  15.1  295  26 13   8.5   4.6 |  -9.0  15.8  300  27 14   8.6   4.7
 18000  -8.2  17.2  295  25 13   8.6   4.7 |  -7.7  18.1  305  26 13   8.4   4.6
 17500  -6.9  19.6  300  23 12   8.6   4.7 |  -6.6  20.1  305  23 12   8.1   4.4
 17000  -5.7  21.7  300  22 11   8.7   4.8 |  -4.8  23.4  305  19 10   7.8   4.3
 16500  -3.8  25.2  300  20 10   8.1   4.5 |  -3.7  25.3  305  15  8   7.4   4.1
 16000  -2.6  27.3  300  18  9   8.1   4.4 |  -2.6  27.3  295  12  6   7.5   4.1
 15500  -1.4  29.5  300  16  8   7.9   4.3 |  -1.5  29.3  285   9  5   8.1   4.4
 15000  -0.2  31.6  295  13  7   7.8   4.3 |  -0.3  31.5  270   7  4   7.9   4.4
 14500   1.0  33.8  290  11  6   9.0   4.9 |   0.9  33.6  255   7  3   8.7   4.8
 14000   2.4  36.3  290   9  5   9.0   4.9 |   2.2  36.0  240   7  4   8.8   4.8
 13500   3.7  38.7  280   8  4   8.8   4.9 |   3.6  38.5  225   7  4   8.9   4.9
 13000   5.0  41.0  275   7  3   8.8   4.8 |   4.9  40.8  220   8  4   9.0   4.9
 12500   6.3  43.3  270   5  3   8.8   4.8 |   6.2  43.2  220   8  4   8.8   4.9
 12000   7.6  45.7  265   5  2   8.7   4.8 |   7.5  45.5  215   8  4   8.7   4.8
 11500   8.9  48.0  260   4  2   8.2   4.5 |   8.8  47.8  215   8  4   8.4   4.6
 11000  10.0  50.0  250   4  2   7.5   4.1 |  10.0  50.0  215   9  4   7.8   4.3
 10500  11.1  52.0  240   4  2   4.9   2.7 |  11.1  52.0  215   9  5   3.9   2.1
 10250  11.3  52.3  240   4  2   3.2   1.7 |  11.2  52.2  215   9  5   3.7   2.0
 10000  11.7  53.1  240   4  2   6.2   3.4 |  11.8  53.2  215   9  5  10.1   5.6
  9750  12.1  53.8  235   5  2   7.3   4.0 |  12.6  54.7  215  10  5  10.6   5.8
  9500  12.5  54.5  230   5  3   1.7   1.0 |  13.3  55.9  215  10  5   7.5   4.1
  9250  12.3  54.1  230   6  3  -1.6  -0.9 |  13.6  56.5  220  10  5   4.4   2.4
  9000  12.2  54.0  230   6  3  -4.3  -2.3 |  13.8  56.8  220  10  5   4.2   2.3
  8750  11.5  52.7  215   8  4  -7.7  -4.2 |  14.0  57.2  220  11  6   3.2   1.8
  8500  10.9  51.6  205   9  4  -3.1  -1.7 |  14.0  57.2  220  11  5   0.1   0.0
  8250  10.6  51.1  185   9  5  -2.6  -1.4 |  13.8  56.8  210  10  5  -3.0  -1.6
  8000  10.3  50.5  170  10  5   1.0   0.6 |  13.5  56.3  195   9  5  -0.7  -0.4
  7750  10.6  51.1  165  11  6   9.0   4.9 |  13.5  56.3  180   9  5   4.0   2.2
  7500  11.4  52.5  165  11  6  10.6   5.8 |  13.9  57.0  170   9  5   8.6   4.7
  7250  12.1  53.8  160  11  6  10.0   5.5 |  14.6  58.3  165   9  5   9.7   5.3
  7000  12.9  55.2  160  11  6  10.3   5.6 |  15.3  59.5  165   9  5   9.8   5.4
  6750  13.6  56.5  160  11  6  10.3   5.7 |  16.1  61.0  160   9  5  10.1   5.5
  6500  14.4  57.9  160  11  5  10.3   5.6 |  16.8  62.2  160   9  5   9.8   5.4
  6250  15.2  59.4  160  10  5  10.1   5.6 |  17.6  63.7  160   9  5   9.9   5.4
  6000  15.9  60.6  160  10  5  10.7   5.9 |  18.3  64.9  160   9  4   9.7   5.3
  5750  16.9  62.4  155  10  5  16.0   8.8 |  19.0  66.2  155   8  4  10.7   5.9
  5500  18.3  64.9  155   9  5  23.0  12.6 |  19.9  67.8  155   7  4  12.7   7.0
________________________________________________________________________________

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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