Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 241252
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0652 MDT Friday, October 24, 2014

This forecast is for Friday, October 24, 2014:

If the trigger temperature of 75.4 F/24.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 589 ft/min (3.0 m/s)
   Maximum height of thermals.................. 13029 ft MSL (7744 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 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................. 11494 ft MSL (6208 ft AGL)
Thermal soaring outlook for Saturday 10/25..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12913 ft MSL (7628 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 13405 ft MSL (8120 ft AGL)
Wave soaring outlook for Saturday 10/25........ Poor

Remarks... None

Sunrise/Sunset.................... 07:19:26 / 18:08:50 MDT
Total possible sunshine........... 10 hr 49 min 24 sec (649 min 24 sec)
Altitude of sun at 12:43:44 MDT... 38.34 degrees

Upper air data from rawinsonde observation taken on 10/24/2014 at 0600 MDT

Freezing level.................. 15306 ft MSL (10021 ft AGL)
Convective condensation level... 22329 ft MSL (17044 ft AGL)
Lifted condensation level....... 19768 ft MSL (14483 ft AGL)
Lifted index.................... +4.0
K index......................... +3.9

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  -66.9 -88.4   300   54   28   0.1   0.1   84.8 184.7    32.2      M    M
 45000  -68.1 -90.6   315   64   33   0.9   0.5   57.2 134.9    17.6      M    M
 40000  -58.6 -73.5   305   63   32  10.0   5.5   49.0 120.3    13.4      M    M
 38000  -53.7 -64.7   305   57   29   7.1   3.9   47.4 117.4    12.7      M    M
 36000  -49.4 -56.9   305   44   23   7.1   3.9   45.2 113.4    11.5      M    M
 34000  -44.4 -47.9   295   38   20   8.8   4.8   44.0 111.2    10.9      M    M
 32000  -39.1 -38.4   285   39   20   8.8   4.8   43.3 109.9    10.6      M    M
 30000  -33.2 -27.8   275   41   21   7.9   4.3   42.6 108.6    10.3      M    M
 29000  -30.9 -23.6   280   42   22   7.7   4.2   41.8 107.2     9.8      M    M
 28000  -28.6 -19.5   285   40   21   7.7   4.2   40.9 105.7     9.3      M    M
 27000  -26.3 -15.3   290   38   20   7.3   4.0   40.1 104.2     8.7      M    M
 26000  -24.2 -11.6   295   37   19   8.0   4.4   39.2 102.6     8.1      M    M
 25000  -21.7  -7.1   300   36   18   7.5   4.1   38.6 101.5     7.7      M    M
 24000  -19.7  -3.5   300   30   15   7.3   4.0   37.6  99.6     6.9      M    M
 23000  -17.2   1.0   305   23   12   8.8   4.8   37.1  98.8     6.6      M    M
 22000  -15.2   4.6   305   26   13  -0.0  -0.0   36.0  96.8     5.6      M    M
 21000  -12.9   8.8   310   28   15   9.4   5.2   35.3  95.5     5.1      M    M
 20000  -10.1  13.8   310   31   16   5.5   3.0   35.2  95.3     5.0      M    M
 19500   -9.6  14.7   315   33   17   7.8   4.3   34.2  93.5     4.1      M    M
 19000   -8.3  17.1   315   35   18   7.6   4.1   33.9  93.0     3.9      M    M
 18500   -7.2  19.0   310   36   19   7.6   4.2   33.5  92.3     3.7      M    M
 18000   -6.4  20.5   310   37   19   3.4   1.9   32.8  91.0     3.0      M    M
 17500   -5.8  21.6   310   32   17   4.9   2.7   31.7  89.1     2.1      M    M
 17000   -4.7  23.5   315   27   14   8.8   4.8   31.4  88.5     1.8      M    M
 16500   -3.4  25.9   315   22   11   8.6   4.7   31.2  88.1     1.7      M    M
 16000   -2.1  28.2   320   16    8   8.6   4.7   31.0  87.9     1.6      M    M
 15500   -0.8  30.6   320   12    6   8.6   4.7   30.9  87.5     1.4      M    M
 15000    1.1  34.0   320    9    5   8.6   4.7   30.6  87.0     1.1      M    M
 14500    2.4  36.3   325   12    6   8.6   4.7   30.4  86.7     0.9      M    M
 14000    3.7  38.7   325   16    8   8.7   4.8   30.2  86.3     0.8      M    M
 13500    5.0  41.0   315   18    9  10.2   5.6   30.0  85.9     0.6      M    M
 13000    5.4  41.7   310   21   11  -5.3  -2.9   28.8  83.9    -0.4    588  3.0
 12500    5.5  41.9   310   24   13   4.8   2.6   27.2  80.9    -1.9    572  2.9
 12000    6.3  43.3   305   27   14   5.8   3.2   26.6  79.8    -2.5    532  2.7
 11500    7.2  45.0   295   27   14   5.9   3.2   26.0  78.7    -3.1    491  2.5
 11000    8.1  46.6   290   27   14   5.6   3.0   25.4  77.6    -3.7    450  2.3
 10500    9.1  48.4   290   26   13   9.4   5.1   25.0  77.0    -4.1    403  2.0
 10250    9.8  49.6   290   25   13   8.5   4.7   24.9  76.8    -4.2    376  1.9
 10000   10.4  50.7   290   24   12   8.3   4.6   24.8  76.6    -4.3    350  1.8
  9750   11.0  51.8   285   23   12   8.4   4.6   24.7  76.5    -4.4    324  1.6
  9500   11.7  53.1   285   21   11   8.4   4.6   24.6  76.3    -4.5    298  1.5
  9250   12.3  54.1   280   20   10   8.4   4.6   24.5  76.1    -4.6    272  1.4
  9000   12.9  55.2   280   19   10   8.4   4.6   24.4  75.9    -4.7    246  1.2
  8750   13.5  56.3   280   18    9   8.4   4.6   24.3  75.7    -4.9    220  1.1
  8500   14.1  57.4   280   17    9   8.4   4.6   24.2  75.5    -5.0    194  1.0
  8250   14.8  58.6   280   17    9   8.4   4.6   24.1  75.3    -5.1    168  0.9
  8000   15.4  59.7   280   16    8   8.4   4.6   24.0  75.2    -5.2    142  0.7
  7750   16.0  60.8   280   15    8   8.4   4.6   23.9  74.9    -5.4    116  0.6
  7500   16.6  61.9   280   14    7   8.4   4.6   23.7  74.7    -5.5     90  0.5
  7250   17.3  63.1   275   14    7   8.2   4.5   23.6  74.5    -5.6     64  0.3
  7000   17.9  64.2   275   13    7   9.0   4.9   23.5  74.3    -5.7     38  0.2
  6750   18.5  65.3   270   11    6   6.2   3.4   23.4  74.1    -5.9     12  0.1
  6500   18.8  65.8   265   10    5   3.0   1.6   23.0  73.3    -6.4      M    M
  6250   19.0  66.2   255    8    4   2.3   1.3   22.4  72.4    -6.9      M    M
  6000   19.2  66.6   245    7    4   5.4   2.9   21.9  71.5    -7.5      M    M
  5750   19.4  66.9   240    5    3  -6.1  -3.3   21.4  70.5    -8.0      M    M
  5500   17.5  63.5   230    3    2 -43.2 -23.7   18.9  66.0   -10.6      5  0.0

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

           10/24/2014 at 0900 MDT          |       10/24/2014 at 1200 MDT
                                           |
K index... -4.9  LI... +6.8                | K index... -5.8  LI... +6.3
CAPE... 0.0  CIN... -1.3                   | 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 -68.9 -92.0  310  44 23   0.7   0.4 | -70.2 -94.4  305  37 19   2.0   1.1
 45000 -65.9 -86.6  310  55 28   5.8   3.2 | -65.4 -85.7  305  43 22   6.2   3.4
 40000 -57.0 -70.6  305  54 28   8.1   4.5 | -55.9 -68.6  300  43 22   8.1   4.4
 38000 -52.3 -62.1  305  51 26   8.0   4.4 | -51.1 -60.0  300  44 23   8.0   4.4
 36000 -47.5 -53.5  305  49 25   8.0   4.4 | -46.2 -51.2  300  44 23   8.0   4.4
 34000 -43.0 -45.4  305  45 23   7.4   4.0 | -41.9 -43.4  295  42 22   7.1   3.9
 32000 -38.5 -37.3  295  40 21   7.4   4.1 | -37.0 -34.6  290  40 20   7.0   3.8
 30000 -33.0 -27.4  290  38 20   8.5   4.7 | -32.2 -26.0  285  38 19   8.3   4.6
 29000 -30.5 -22.9  290  38 19   8.5   4.7 | -29.7 -21.5  285  37 19   8.3   4.6
 28000 -28.0 -18.4  285  37 19   7.7   4.2 | -27.2 -17.0  285  36 18   7.2   4.0
 27000 -25.8 -14.4  290  35 18   7.3   4.0 | -25.2 -13.4  280  34 18   6.6   3.6
 26000 -23.7 -10.7  290  33 17   7.3   4.0 | -23.2  -9.8  280  33 17   6.7   3.6
 25000 -21.5  -6.7  290  30 16   7.3   4.0 | -21.3  -6.3  280  32 16   6.7   3.7
 24000 -19.3  -2.7  300  30 16   7.4   4.1 | -19.1  -2.4  280  31 16   7.4   4.1
 23000 -17.1   1.2  305  32 16   7.4   4.1 | -16.9   1.6  280  30 16   7.4   4.1
 22000 -14.9   5.2  315  34 17   7.6   4.1 | -14.7   5.5  280  30 15   7.6   4.2
 21000 -12.5   9.5  310  32 16   8.2   4.5 | -12.3   9.9  280  29 15   8.2   4.5
 20000 -10.0  14.0  305  29 15   8.2   4.5 |  -9.8  14.4  280  28 15   8.2   4.5
 19500  -8.8  16.2  305  28 15   8.2   4.5 |  -8.6  16.5  280  28 14   8.2   4.5
 19000  -7.5  18.5  305  27 14   7.9   4.4 |  -7.4  18.7  280  28 14   7.9   4.3
 18500  -6.4  20.5  300  26 13   7.9   4.3 |  -6.2  20.8  285  27 14   7.9   4.3
 18000  -5.2  22.6  300  24 13   7.6   4.1 |  -5.0  23.0  285  27 14   7.6   4.2
 17500  -4.1  24.6  300  23 12   6.6   3.6 |  -3.9  25.0  290  26 14   6.8   3.8
 17000  -3.1  26.4  300  22 11   6.7   3.7 |  -2.9  26.8  290  25 13   7.0   3.8
 16500  -2.2  28.0  300  21 11   6.1   3.3 |  -2.0  28.4  290  25 13   5.5   3.0
 16000  -1.3  29.7  295  21 11   6.1   3.3 |  -0.7  30.7  290  23 12   5.5   3.0
 15500   0.1  32.2  290  19 10   5.5   3.0 |   0.1  32.2  290  22 11   5.5   3.0
 15000   0.9  33.6  285  18  9   5.6   3.1 |   0.9  33.6  285  21 11   5.4   3.0
 14500   1.7  35.1  280  17  9   5.9   3.2 |   1.8  35.2  285  19 10   6.0   3.3
 14000   2.6  36.7  280  15  8   6.0   3.3 |   2.6  36.7  285  17  9   6.0   3.3
 13500   3.5  38.3  275  14  7   6.5   3.6 |   3.6  38.5  280  15  8   6.7   3.7
 13000   4.5  40.1  275  12  6   6.8   3.8 |   4.6  40.3  280  13  6   7.2   3.9
 12500   5.5  41.9  280  10  5   7.4   4.0 |   5.7  42.3  280  10  5   7.6   4.1
 12000   6.7  44.1  280   8  4   8.1   4.4 |   6.9  44.4  280   9  4   8.0   4.4
 11500   7.9  46.2  285   6  3   8.5   4.7 |   8.1  46.6  275   7  3   8.1   4.5
 11000   9.3  48.7  300   5  3   9.0   5.0 |   9.3  48.7  280   6  3   8.2   4.5
 10500  10.7  51.3  310   6  3   5.2   2.9 |  10.6  51.1  290   6  3   5.1   2.8
 10250  10.9  51.6  315   6  3   5.2   2.9 |  10.8  51.4  295   6  3   5.7   3.1
 10000  11.6  52.9  315   6  3  11.4   6.3 |  11.5  52.7  295   6  3  10.8   5.9
  9750  12.5  54.5  315   7  4  11.9   6.5 |  12.3  54.1  300   7  3  10.7   5.9
  9500  13.3  55.9  315   8  4   9.0   4.9 |  13.0  55.4  300   7  4   8.7   4.8
  9250  13.8  56.8  315   9  5   5.1   2.8 |  13.6  56.5  300   8  4   6.3   3.4
  9000  14.2  57.6  310  10  5   7.2   3.9 |  14.1  57.4  300   9  4   7.5   4.1
  8750  14.8  58.6  310  11  6   8.9   4.9 |  14.6  58.3  295   9  5   8.1   4.5
  8500  15.4  59.7  305  12  6   7.1   3.9 |  15.2  59.4  295  10  5   7.0   3.8
  8250  15.8  60.4  300  12  6   6.0   3.3 |  15.7  60.3  290  10  5   6.3   3.5
  8000  16.3  61.3  300  13  7   5.9   3.2 |  16.1  61.0  290  10  5   6.1   3.4
  7750  16.7  62.1  295  13  7   4.9   2.7 |  16.5  61.7  285  10  5   5.3   2.9
  7500  17.0  62.6  295  13  7   3.7   2.0 |  16.8  62.2  280   9  5   4.8   2.7
  7250  17.2  63.0  295  12  6   2.9   1.6 |  17.2  63.0  270   7  4   4.8   2.7
  7000  17.3  63.1  290  11  6   3.7   2.0 |  17.5  63.5  255   6  3   4.3   2.4
  6750  17.5  63.5  290  11  5   1.4   0.8 |  17.8  64.0  235   5  2   4.9   2.7
  6500  17.4  63.3  280   9  5  -3.1  -1.7 |  18.2  64.8  220   4  2   6.6   3.6
  6250  17.2  63.0  270   8  4  -0.3  -0.2 |  18.6  65.5  205   4  2   6.3   3.5
  6000  17.0  62.6  260   8  4 -11.7  -6.4 |  19.1  66.4  190   5  2   7.8   4.3
  5750  15.2  59.4  240   7  4 -27.9 -15.3 |  19.8  67.6  185   5  3  12.8   7.0
  5500  13.2  55.8  215   6  3 -20.2 -11.1 |  20.9  69.6  185   5  2  16.2   8.9

           10/24/2014 at 1500 MDT          |       10/24/2014 at 1800 MDT
                                           |
K index... -0.2  LI... +5.0                | K index... +4.0  LI... +4.4
CAPE... 0.0  CIN... -0.9                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -71.5 -96.7  295  36 19   3.3   1.8 | -72.0 -97.6  290  33 17   3.4   1.9
 45000 -65.0 -85.0  300  39 20   6.6   3.6 | -65.1 -85.2  280  33 17   7.0   3.8
 40000 -55.0 -67.0  290  38 20   7.7   4.2 | -54.7 -66.5  275  37 19   6.8   3.7
 38000 -50.4 -58.7  295  41 21   7.7   4.2 | -50.6 -59.1  285  40 21   6.8   3.7
 36000 -45.8 -50.4  295  44 23   7.7   4.2 | -46.6 -51.9  295  45 23   6.8   3.7
 34000 -41.4 -42.5  295  47 24   7.2   4.0 | -42.0 -43.6  295  47 24   7.9   4.3
 32000 -36.5 -33.7  295  50 25   7.1   3.9 | -36.6 -33.9  300  50 26   7.8   4.3
 30000 -31.5 -24.7  295  49 25   8.5   4.7 | -31.7 -25.1  300  48 25   8.2   4.5
 29000 -28.9 -20.0  300  49 25   8.5   4.7 | -29.3 -20.7  300  47 24   8.2   4.5
 28000 -26.4 -15.5  295  48 25   7.9   4.3 | -26.8 -16.2  300  46 24   8.0   4.4
 27000 -24.1 -11.4  295  46 24   7.6   4.2 | -24.4 -11.9  295  42 22   8.0   4.4
 26000 -21.8  -7.2  290  43 22   7.6   4.2 | -22.0  -7.6  290  39 20   8.0   4.4
 25000 -19.5  -3.1  290  41 21   7.6   4.1 | -19.6  -3.3  285  36 19   7.8   4.3
 24000 -17.9  -0.2  280  39 20   5.0   2.7 | -17.6   0.3  285  37 19   6.6   3.6
 23000 -16.4   2.5  275  39 20   5.1   2.8 | -15.6   3.9  285  39 20   6.6   3.6
 22000 -14.9   5.2  265  39 20   5.7   3.1 | -13.6   7.5  285  41 21   6.6   3.6
 21000 -12.6   9.3  265  37 19   8.0   4.4 | -11.7  10.9  275  39 20   6.3   3.5
 20000 -10.3  13.5  265  34 17   8.0   4.4 |  -9.9  14.2  270  38 20   6.4   3.5
 19500  -9.1  15.6  265  32 17   8.1   4.4 |  -8.9  16.0  265  38 19   6.3   3.4
 19000  -7.9  17.8  265  31 16   7.2   3.9 |  -7.9  17.8  265  37 19   8.1   4.5
 18500  -6.9  19.6  265  30 15   7.2   3.9 |  -6.7  19.9  265  36 19   8.0   4.4
 18000  -5.8  21.6  265  29 15   7.0   3.8 |  -5.5  22.1  265  35 18   7.3   4.0
 17500  -4.8  23.4  265  27 14   6.7   3.7 |  -4.6  23.7  265  33 17   5.8   3.2
 17000  -3.8  25.2  270  26 13   6.8   3.7 |  -3.7  25.3  265  30 16   5.8   3.2
 16500  -2.8  27.0  270  25 13   6.0   3.3 |  -2.8  27.0  265  28 14   6.0   3.3
 16000  -1.5  29.3  270  22 11   6.0   3.3 |  -2.0  28.4  265  26 14   6.0   3.3
 15500  -0.5  31.1  270  21 11   6.8   3.7 |  -0.7  30.7  265  24 12   6.2   3.4
 15000   0.5  32.9  275  19 10   6.7   3.7 |   0.2  32.4  265  22 11   6.2   3.4
 14500   1.5  34.7  275  18  9   7.3   4.0 |   1.1  34.0  265  20 10   7.4   4.0
 14000   2.6  36.7  275  16  8   7.4   4.0 |   2.2  36.0  265  19 10   7.5   4.1
 13500   3.7  38.7  280  15  8   7.6   4.2 |   3.3  37.9  265  17  9   8.1   4.5
 13000   4.8  40.6  280  14  7   7.7   4.2 |   4.5  40.1  265  16  8   8.4   4.6
 12500   6.0  42.8  285  13  7   8.1   4.4 |   5.7  42.3  265  14  7   8.4   4.6
 12000   7.2  45.0  285  12  6   8.4   4.6 |   7.0  44.6  260  13  7   8.3   4.6
 11500   8.5  47.3  290  12  6   8.1   4.4 |   8.3  46.9  260  11  6   8.0   4.4
 11000   9.6  49.3  295  11  6   7.2   3.9 |   9.5  49.1  255   9  5   7.3   4.0
 10500  10.7  51.3  295  10  5   3.6   2.0 |  10.6  51.1  245   8  4   3.9   2.2
 10250  10.8  51.4  300  10  5   4.2   2.3 |  10.8  51.4  245   7  4   5.7   3.1
 10000  11.4  52.5  295   8  4   9.8   5.4 |  11.6  52.9  240   7  3  11.5   6.3
  9750  12.0  53.6  295   7  4   9.0   4.9 |  12.4  54.3  230   6  3  10.4   5.7
  9500  12.7  54.9  290   6  3   7.7   4.2 |  13.2  55.8  220   6  3   9.0   5.0
  9250  13.2  55.8  280   5  2   6.2   3.4 |  13.8  56.8  210   6  3   7.2   4.0
  9000  13.7  56.7  260   4  2   8.5   4.7 |  14.3  57.7  205   5  3   8.7   4.8
  8750  14.4  57.9  235   3  2   9.7   5.3 |  15.0  59.0  195   5  3   9.2   5.0
  8500  15.1  59.2  205   3  2   8.9   4.9 |  15.7  60.3  190   5  3   8.9   4.9
  8250  15.7  60.3  195   4  2   8.5   4.6 |  16.3  61.3  185   5  2   8.8   4.8
  8000  16.3  61.3  185   4  2   8.6   4.7 |  16.9  62.4  180   4  2   8.9   4.9
  7750  17.0  62.6  180   5  2   8.8   4.8 |  17.6  63.7  175   4  2   9.0   4.9
  7500  17.6  63.7  180   5  2   9.4   5.2 |  18.3  64.9  165   4  2   9.3   5.1
  7250  18.3  64.9  180   5  2   9.6   5.3 |  18.9  66.0  165   3  2   9.4   5.1
  7000  19.0  66.2  180   5  2   9.9   5.4 |  19.6  67.3  160   3  2   9.5   5.2
  6750  19.8  67.6  180   4  2  10.3   5.7 |  20.3  68.5  150   3  1   9.4   5.1
  6500  20.5  68.9  180   4  2  10.2   5.6 |  21.0  69.8  145   2  1   8.9   4.9
  6250  21.3  70.3  180   4  2   9.9   5.4 |  21.7  71.1  135   2  1   8.9   4.9
  6000  22.0  71.6  180   4  2  10.4   5.7 |  22.3  72.1  120   2  1   8.9   4.9
  5750  22.9  73.2  175   4  2  12.8   7.0 |  22.9  73.2  105   1  1   5.3   2.9
  5500  23.9  75.0  175   4  2  15.3   8.4 |  23.0  73.4  090   1  1  -0.3  -0.2
________________________________________________________________________________

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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