Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 281219
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0519 MST Friday, November 28, 2014

This forecast is for Friday, November 28, 2014:

If the trigger temperature of 67.2 F/19.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 551 ft/min (2.8 m/s)
   Maximum height of thermals.................. 12912 ft MSL (7627 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1200 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6606 ft MSL (1321 ft AGL)
Thermal soaring outlook for Saturday 11/29..... Poor

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... 14405 ft MSL (9120 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 15637 ft MSL (10352 ft AGL)
Wave soaring outlook for Saturday 11/29........ Good

Remarks...

Sunrise/Sunset.................... 06:58:29 / 16:36:29 MST
Total possible sunshine........... 9 hr 38 min 1 sec (578 min 1 sec)
Altitude of sun at 11:47:38 MST... 28.90 degrees

Upper air data from rawinsonde observation taken on 11/28/2014 at 0500 MST

Freezing level.................. 12105 ft MSL (6820 ft AGL)
Convective condensation level... 23345 ft MSL (18060 ft AGL)
Lifted condensation level....... 19621 ft MSL (14335 ft AGL)
Lifted index.................... +7.3
K index......................... -11.0

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  -63.9 -83.0   285   42   21   3.6   2.0   92.0 197.5    40.3      M    M
 45000  -66.2 -87.2   305   66   34   0.6   0.3   63.2 145.8    25.6      M    M
 40000  -63.4 -82.1   310   81   42   8.6   4.7   44.7 112.4    15.2      M    M
 38000  -58.0 -72.4   315   93   48   9.1   5.0   44.0 111.2    15.1      M    M
 36000  -54.4 -65.9   310   81   42   9.0   4.9   40.8 105.5    13.3      M    M
 34000  -49.8 -57.6   305   72   37   8.7   4.8   39.0 102.2    12.4      M    M
 32000  -44.0 -47.2   305   66   34   7.8   4.3   37.7  99.9    11.8      M    M
 30000  -39.4 -38.9   300   54   28   8.0   4.4   36.1  97.0    10.9      M    M
 29000  -37.0 -34.6   300   50   26   8.1   4.4   35.4  95.7    10.5      M    M
 28000  -34.5 -30.1   295   47   24   9.0   5.0   34.9  94.8    10.2      M    M
 27000  -31.9 -25.4   295   44   23   8.8   4.8   34.6  94.3    10.1      M    M
 26000  -29.2 -20.6   300   44   23   8.8   4.8   34.2  93.6     9.9      M    M
 25000  -26.6 -15.9   300   44   23   8.8   4.8   33.9  93.1     9.8      M    M
 24000  -23.8 -10.8   305   49   25   7.9   4.3   33.7  92.6     9.7      M    M
 23000  -22.1  -7.8   285   51   26   6.1   3.3   32.2  90.0     8.6      M    M
 22000  -20.0  -4.0   290   51   26   7.2   3.9   31.2  88.1     7.8      M    M
 21000  -17.9  -0.2   295   52   27   6.4   3.5   30.3  86.5     7.1      M    M
 20000  -16.5   2.3   300   53   27   5.1   2.8   28.5  83.3     5.7      M    M
 19500  -15.3   4.5   300   53   27   9.6   5.3   28.2  82.7     5.4      M    M
 19000  -13.9   7.0   295   53   27   9.4   5.2   28.1  82.6     5.3      M    M
 18500  -12.6   9.3   295   53   27   7.9   4.3   27.9  82.2     5.2      M    M
 18000  -11.4  11.5   295   53   28   8.0   4.4   27.6  81.6     4.9      M    M
 17500  -10.2  13.6   295   54   28   8.0   4.4   27.3  81.1     4.7      M    M
 17000   -9.0  15.8   290   54   28   8.2   4.5   27.0  80.6     4.5      M    M
 16500   -7.7  18.1   290   55   28   8.5   4.6   26.8  80.2     4.4      M    M
 16000   -5.8  21.6   290   55   28   8.9   4.9   26.5  79.7     4.2      M    M
 15500   -4.7  23.5   285   56   29   5.1   2.8   26.0  78.9     3.8      M    M
 15000   -3.9  25.0   280   56   29   5.8   3.2   25.3  77.6     3.2      M    M
 14500   -3.6  25.5   285   49   25  -8.6  -4.7   24.1  75.3     2.0      M    M
 14000   -3.9  25.0   285   43   22   9.9   5.5   22.1  71.8     0.2      M    M
 13500   -2.6  27.3   285   39   20   9.1   5.0   22.0  71.6     0.1      M    M
 13000   -1.2  29.8   285   34   18   9.3   5.1   21.9  71.4     0.0      M    M
 12500   -0.9  30.4   285   30   15   2.5   1.4   20.7  69.3    -1.1    627  3.2
 12000    0.4  32.7   285   25   13   8.3   4.6   20.6  69.0    -1.2    572  2.9
 11500    1.8  35.2   285   20   11   8.7   4.8   20.4  68.7    -1.4    518  2.6
 11000    3.1  37.6   290   16    8   8.8   4.8   20.2  68.4    -1.5    464  2.4
 10500    4.4  39.9   285   15    8   8.7   4.8   20.1  68.1    -1.7    410  2.1
 10250    5.0  41.0   280   15    8   8.9   4.9   20.0  68.0    -1.8    383  1.9
 10000    5.7  42.3   280   14    7   9.1   5.0   19.9  67.9    -1.9    355  1.8
  9750    6.4  43.5   275   13    7   9.1   5.0   19.9  67.8    -1.9    328  1.7
  9500    7.1  44.8   275   12    6   9.1   5.0   19.8  67.7    -2.0    300  1.5
  9250    7.7  45.9   275   11    6   9.1   5.0   19.8  67.7    -2.0    272  1.4
  9000    8.4  47.1   270   10    5   9.1   5.0   19.8  67.6    -2.1    244  1.2
  8750    9.1  48.4   265   10    5   9.1   5.0   19.7  67.5    -2.1    217  1.1
  8500    9.8  49.6   260   10    5   9.1   5.0   19.7  67.4    -2.2    189  1.0
  8250   10.4  50.7   255   10    5   9.1   5.0   19.6  67.3    -2.2    161  0.8
  8000   11.1  52.0   250   10    5   9.1   5.0   19.6  67.2    -2.3    134  0.7
  7750   11.8  53.2   250   10    5   9.1   5.0   19.5  67.1    -2.4    106  0.5
  7500   12.5  54.5   255   11    6   9.1   5.0   19.4  67.0    -2.4     78  0.4
  7250   13.2  55.8   255   11    6   8.9   4.9   19.4  66.9    -2.5     50  0.3
  7000   13.8  56.8   255   12    6   9.7   5.3   19.3  66.8    -2.6     23  0.1
  6750   14.5  58.1   240   11    6   6.8   3.7   19.3  66.7    -2.6      M    M
  6500   14.7  58.5   225   11    6  -1.7  -0.9   18.7  65.7    -3.2      M    M
  6250   14.6  58.3   210   11    6   2.2   1.2   17.8  64.1    -4.1      M    M
  6000   14.4  57.9   195   13    7 -18.5 -10.1   17.0  62.5    -5.0      M    M
  5750   11.8  53.2   195    9    5 -36.1 -19.8   13.6  56.6    -8.3     46  0.2
  5500   10.1  50.2   205    4    2  -6.0  -3.3   11.2  52.2   -10.8     90  0.5

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

           11/28/2014 at 0800 MST          |       11/28/2014 at 1100 MST
                                           |
K index... -13.7  LI... +6.8               | K index... -10.8  LI... +7.7
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -68.2 -90.8  295  58 30   1.8   1.0 | -67.0 -88.6  290  54 28   0.2   0.1
 45000 -65.3 -85.5  300  74 38   2.5   1.4 | -66.3 -87.3  290  73 38   3.6   2.0
 40000 -61.6 -78.9  305  89 46   2.4   1.3 | -61.1 -78.0  295  90 46   3.5   1.9
 38000 -57.8 -72.0  305  87 45   7.4   4.1 | -57.4 -71.3  295  88 45   6.9   3.8
 36000 -53.3 -63.9  305  83 43   7.4   4.1 | -53.2 -63.8  300  84 43   6.9   3.8
 34000 -48.9 -56.0  300  79 40   7.4   4.1 | -48.9 -56.0  300  78 40   7.4   4.1
 32000 -44.4 -47.9  300  74 38   7.4   4.1 | -44.5 -48.1  295  69 36   7.4   4.1
 30000 -39.1 -38.4  300  64 33   8.4   4.6 | -39.0 -38.2  295  57 30   8.9   4.9
 29000 -36.6 -33.9  295  56 29   8.4   4.6 | -36.3 -33.3  290  51 26   8.9   4.9
 28000 -34.1 -29.4  290  50 26   8.4   4.6 | -33.7 -28.7  290  46 23   8.9   4.9
 27000 -31.7 -25.1  285  44 23   7.9   4.3 | -31.1 -24.0  285  42 22   8.3   4.5
 26000 -29.3 -20.7  285  40 21   7.9   4.3 | -28.6 -19.5  290  41 21   8.3   4.5
 25000 -27.0 -16.6  285  36 19   7.9   4.3 | -26.2 -15.2  290  41 21   8.3   4.5
 24000 -24.5 -12.1  285  34 18   8.8   4.8 | -23.6 -10.5  290  41 21   8.7   4.8
 23000 -21.9  -7.4  290  36 19   8.8   4.8 | -21.0  -5.8  295  43 22   8.7   4.8
 22000 -19.3  -2.7  295  38 20   8.7   4.8 | -18.4  -1.1  295  45 23   8.7   4.7
 21000 -16.7   1.9  300  41 21   8.0   4.4 | -16.0   3.2  295  46 23   7.6   4.2
 20000 -14.3   6.3  300  42 22   8.0   4.4 | -13.7   7.3  295  46 23   7.6   4.2
 19500 -13.1   8.4  300  43 22   8.0   4.4 | -12.5   9.5  295  46 23   7.6   4.2
 19000 -11.9  10.6  300  44 23   8.0   4.4 | -11.4  11.5  295  46 23   7.7   4.2
 18500 -10.7  12.7  300  44 23   7.7   4.2 | -10.3  13.5  295  46 23   7.1   3.9
 18000  -9.6  14.7  300  45 23   7.7   4.2 |  -9.2  15.4  295  46 23   7.1   3.9
 17500  -8.4  16.9  295  45 23   7.4   4.0 |  -8.2  17.2  295  46 24   6.9   3.8
 17000  -7.3  18.9  295  46 24   7.1   3.9 |  -7.2  19.0  290  46 24   6.7   3.7
 16500  -6.3  20.7  295  46 24   7.1   3.9 |  -6.2  20.8  290  46 24   6.7   3.7
 16000  -5.2  22.6  295  47 24   6.8   3.8 |  -5.2  22.6  290  46 24   6.3   3.4
 15500  -4.2  24.4  295  48 25   6.9   3.8 |  -3.8  25.2  290  47 24   6.2   3.4
 15000  -2.7  27.1  295  49 25   6.6   3.6 |  -2.9  26.8  290  47 24   5.9   3.2
 14500  -1.7  28.9  295  49 25   6.7   3.7 |  -2.0  28.4  290  47 24   5.9   3.3
 14000  -0.8  30.6  295  49 25   5.8   3.2 |  -1.2  29.8  290  47 24   5.7   3.1
 13500   0.1  32.2  295  49 25   5.9   3.3 |  -0.3  31.5  290  46 24   5.8   3.2
 13000   0.9  33.6  295  48 25   6.9   3.3 |   0.5  32.9  290  45 23   5.6   3.1
 12500   1.8  35.2  295  47 24   6.0   3.3 |   1.3  34.3  290  44 23   5.6   3.1
 12000   2.7  36.9  290  46 24   5.3   2.9 |   2.2  36.0  290  43 22   5.7   3.1
 11500   3.4  38.1  295  43 22   5.2   2.9 |   3.0  37.4  290  40 20   5.8   3.2
 11000   4.1  39.4  295  41 21   4.3   2.4 |   3.8  38.8  290  37 19   4.9   2.7
 10500   4.7  40.5  295  38 19   3.8   2.1 |   4.5  40.1  290  34 17   4.3   2.4
 10250   5.0  41.0  290  36 19   5.7   3.1 |   4.8  40.6  290  32 16   6.1   3.3
 10000   5.5  41.9  290  33 17   5.8   3.2 |   5.3  41.5  290  29 15   6.4   3.5
  9750   5.8  42.4  290  31 16   3.9   2.2 |   5.7  42.3  290  26 13   4.6   2.5
  9500   6.1  43.0  290  28 14   4.7   2.6 |   6.1  43.0  285  23 12   5.4   3.0
  9250   6.4  43.5  290  25 13   3.6   2.0 |   6.5  43.7  285  21 11   3.8   2.1
  9000   6.7  44.1  290  22 11   3.6   2.0 |   6.7  44.1  285  17  9   3.9   2.2
  8750   7.0  44.6  290  19 10   4.8   2.6 |   7.1  44.8  280  14  7   5.7   3.1
  8500   7.3  45.1  285  16  8   4.3   2.4 |   7.5  45.5  270  11  6   4.8   2.6
  8250   7.7  45.9  285  13  6   5.3   2.9 |   7.9  46.2  255   8  4   6.7   3.7
  8000   8.1  46.6  275   9  5   6.7   3.7 |   8.5  47.3  235   6  3   8.6   4.7
  7750   8.6  47.5  265   7  3   7.2   3.9 |   9.1  48.4  215   6  3   7.9   4.3
  7500   9.2  48.6  245   5  3   7.7   4.2 |   9.7  49.5  200   6  3   7.9   4.4
  7250   9.8  49.6  230   5  2   8.9   4.9 |  10.3  50.5  190   7  4   9.0   5.0
  7000  10.5  50.9  220   5  2   8.9   4.9 |  11.0  51.8  185   7  4   9.5   5.2
  6750  11.1  52.0  210   5  2  10.9   6.0 |  11.7  53.1  185   8  4  10.2   5.6
  6500  11.8  53.2  205   5  3   3.1   1.7 |  12.4  54.3  180   8  4   7.3   4.0
  6250  11.5  52.7  200   6  3  -7.8  -4.3 |  12.8  55.0  185   8  4   2.9   1.6
  6000  11.0  51.8  200   7  4  -4.1  -2.3 |  12.9  55.2  185   8  4   3.0   1.7
  5750  10.6  51.1  200   9  4 -10.8  -5.9 |  13.0  55.4  185   8  4  -2.7  -1.5
  5500   8.5  47.3  200  10  5 -50.3 -27.6 |  12.4  54.3  190   8  4 -10.8  -5.9

           11/28/2014 at 1400 MST          |       11/28/2014 at 1700 MST
                                           |
K index... -10.3  LI... +8.2               | K index... -13.0  LI... +9.1
CAPE... 0.0  CIN... -0.4                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -67.0 -88.6  285  56 29  -1.2  -0.7 | -67.2 -89.0  300  48 25  -3.2  -1.7
 45000 -68.5 -91.3  285  83 43   3.8   2.1 | -71.3 -96.3  290  87 45   7.0   3.8
 40000 -61.8 -79.2  290  93 48   4.2   2.3 | -62.6 -80.7  285  88 45   5.9   3.2
 38000 -57.7 -71.9  290  88 45   7.5   4.1 | -57.9 -72.2  285  82 42   8.3   4.6
 36000 -53.2 -63.8  290  81 42   7.5   4.1 | -52.9 -63.2  285  74 38   8.3   4.6
 34000 -48.6 -55.5  290  73 38   8.0   4.4 | -47.3 -53.1  285  67 35   8.2   4.5
 32000 -43.7 -46.7  285  64 33   8.0   4.4 | -42.4 -44.3  280  63 32   8.2   4.5
 30000 -38.7 -37.7  280  54 28   9.0   4.9 | -37.4 -35.3  280  60 31   8.5   4.7
 29000 -35.3 -31.5  275  47 24   9.0   4.9 | -34.8 -30.6  280  58 30   8.5   4.7
 28000 -32.6 -26.7  270  42 22   9.0   4.9 | -32.2 -26.0  275  57 29   8.5   4.7
 27000 -30.0 -22.0  265  41 21   8.5   4.6 | -29.8 -21.6  275  57 29   7.9   4.3
 26000 -27.5 -17.5  270  42 22   8.4   4.6 | -27.4 -17.3  275  57 29   7.9   4.3
 25000 -25.0 -13.0  270  44 22   8.4   4.6 | -25.0 -13.0  275  57 29   7.9   4.3
 24000 -22.5  -8.5  275  46 24   7.6   4.2 | -22.7  -8.9  275  57 29   7.7   4.2
 23000 -20.2  -4.4  275  48 25   7.6   4.2 | -20.3  -4.5  275  57 29   7.7   4.2
 22000 -17.9  -0.2  280  51 26   7.6   4.2 | -18.0  -0.4  275  58 30   7.7   4.2
 21000 -15.7   3.7  280  53 27   7.0   3.8 | -15.7   3.7  280  58 30   7.5   4.1
 20000 -13.6   7.5  280  54 28   7.0   3.8 | -13.5   7.7  280  57 29   7.5   4.1
 19500 -12.5   9.5  280  54 28   7.0   3.8 | -12.3   9.9  280  57 29   7.5   4.1
 19000 -11.5  11.3  280  54 28   7.0   3.9 | -11.2  11.8  280  57 29   7.6   4.2
 18500 -10.4  13.3  280  54 28   6.9   3.8 | -10.1  13.8  280  56 29   6.6   3.6
 18000  -9.4  15.1  280  54 28   6.9   3.8 |  -9.2  15.4  280  55 28   6.4   3.5
 17500  -8.4  16.9  280  53 27   6.7   3.7 |  -8.2  17.2  280  54 28   6.2   3.4
 17000  -7.4  18.7  280  52 27   6.4   3.5 |  -7.0  19.4  280  52 27   5.5   3.0
 16500  -6.5  20.3  280  51 26   6.4   3.5 |  -6.1  21.0  280  50 26   5.4   3.0
 16000  -5.6  21.9  280  50 26   5.8   3.2 |  -5.3  22.5  280  48 25   5.4   3.0
 15500  -4.7  23.5  280  49 25   5.9   3.2 |  -4.5  23.9  280  46 24   5.5   3.0
 15000  -3.8  25.2  280  48 25   5.5   3.0 |  -3.8  25.2  280  44 23   4.5   2.5
 14500  -2.7  27.1  285  46 24   5.4   3.0 |  -3.1  26.4  280  42 21   4.6   2.5
 14000  -1.9  28.6  285  45 23   5.6   3.1 |  -2.4  27.7  280  39 20   5.3   2.9
 13500  -1.1  30.0  285  43 22   5.6   3.1 |  -1.6  29.1  285  37 19   5.4   2.9
 13000  -0.2  31.6  285  41 21   5.5   3.0 |  -0.8  30.6  285  35 18   5.8   3.2
 12500   0.6  33.1  285  39 20   5.5   3.0 |   0.0  32.0  285  33 17   5.9   3.3
 12000   1.4  34.5  285  36 19   5.5   3.0 |   0.9  33.6  285  31 16   6.2   3.4
 11500   2.2  36.0  285  31 16   5.5   3.0 |   1.9  35.4  285  28 15   6.4   3.5
 11000   3.0  37.4  280  26 13   5.2   2.9 |   2.8  37.0  285  26 13   5.7   3.1
 10500   3.7  38.7  280  22 11   4.8   2.6 |   3.6  38.5  285  24 12   4.7   2.6
 10250   4.1  39.4  275  20 10   6.3   3.4 |   3.9  39.0  280  23 12   6.3   3.5
 10000   4.6  40.3  270  16  8   7.4   4.1 |   4.5  40.1  280  20 10   7.7   4.2
  9750   5.1  41.2  265  14  7   6.7   3.7 |   5.0  41.0  280  18  9   7.0   3.9
  9500   5.6  42.1  255  11  6   7.0   3.8 |   5.5  41.9  280  16  8   7.2   3.9
  9250   6.2  43.2  240  10  5   6.4   3.5 |   6.1  43.0  275  15  8   7.3   4.0
  9000   6.7  44.1  225   9  4   7.9   4.3 |   6.6  43.9  275  13  7   7.4   4.1
  8750   7.3  45.1  215   9  4   9.5   5.2 |   7.2  45.0  265  11  6   7.5   4.1
  8500   8.0  46.4  205   9  5   9.0   4.9 |   7.7  45.9  260  10  5   7.2   4.0
  8250   8.7  47.7  195   9  5   9.6   5.2 |   8.3  46.9  250   9  5   8.3   4.6
  8000   9.4  48.9  190  10  5   9.7   5.3 |   8.9  48.0  235   8  4   9.8   5.4
  7750  10.1  50.2  190  10  5   9.2   5.0 |   9.7  49.5  230   8  4   9.5   5.2
  7500  10.8  51.4  185  10  5   9.0   4.9 |  10.3  50.5  225   8  4   9.0   4.9
  7250  11.5  52.7  185  10  5   9.9   5.4 |  11.0  51.8  220   8  4   9.9   5.4
  7000  12.3  54.1  185  10  5  10.4   5.7 |  11.8  53.2  220   8  4  10.5   5.8
  6750  13.0  55.4  185  10  5   9.5   5.2 |  12.6  54.7  215   8  4   9.7   5.3
  6500  13.7  56.7  185  11  5   8.9   4.9 |  13.3  55.9  215   8  4   9.1   5.0
  6250  14.4  57.9  185  10  5   8.5   4.7 |  13.9  57.0  215   8  4   8.8   4.8
  6000  14.9  58.8  185   9  5   8.5   4.7 |  14.6  58.3  220   8  4   8.0   4.4
  5750  15.5  59.9  185   8  4   7.7   4.2 |  15.2  59.4  220   8  4  10.8   5.9
  5500  16.0  60.8  190   6  3   7.3   4.0 |  15.9  60.6  220   8  4   4.5   2.4
________________________________________________________________________________

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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