Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 251315
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0615 MST Thursday, December 25, 2014

This forecast is for Thursday, December 25, 2014:

If the trigger temperature of 55.9 F/13.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 5459 ft MSL (174 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. None
Thermal soaring outlook for Friday 12/26....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 16365 ft MSL (11080 ft AGL)
Wave soaring outlook for Friday 12/26.......... Poor

Remarks...

Sunrise/Sunset.................... 07:18:46 / 16:40:39 MST
Total possible sunshine........... 9 hr 21 min 53 sec (561 min 53 sec)
Altitude of sun at 11:59:41 MST... 26.92 degrees

Upper air data from rawinsonde observation taken on 12/25/2014 at 0500 MST

Freezing level.................. 9836 ft MSL (4551 ft AGL)
Convective condensation level... 17095 ft MSL (11810 ft AGL)
Lifted condensation level....... 11980 ft MSL (6695 ft AGL)
Lifted index.................... +10.3
K index......................... +12.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -54.1 -65.4   225   17    9   3.8   2.1  110.3 230.6    59.6      M    M
 45000  -49.7 -57.5   245   66   34   3.0   1.7   91.8 197.3    52.5      M    M
 40000  -54.3 -65.7   235   72   37  -5.5  -3.0   61.4 142.5    36.2      M    M
 38000  -56.3 -69.3   225   81   42   7.2   3.9   49.5 121.0    29.1      M    M
 36000  -55.6 -68.1   225   77   40   1.7   1.0   42.0 107.5    24.8      M    M
 34000  -52.5 -62.5   230   73   37   2.7   1.5   38.0 100.5    22.6      M    M
 32000  -52.5 -62.5   235   66   34   2.4   1.3   29.8  85.7    17.3      M    M
 30000  -48.3 -54.9   245   57   29   8.9   4.9   26.6  79.9    15.4      M    M
 29000  -45.7 -50.3   240   52   27   8.8   4.8   26.2  79.2    15.3      M    M
 28000  -43.0 -45.4   240   48   25   8.8   4.8   25.9  78.6    15.2      M    M
 27000  -40.4 -40.7   235   44   22   8.9   4.9   25.5  77.9    15.1      M    M
 26000  -38.2 -36.8   225   40   21   7.2   3.9   24.6  76.4    14.6      M    M
 25000  -35.7 -32.3   220   37   19   9.6   5.3   24.2  75.5    14.4      M    M
 24000  -32.8 -27.0   225   34   18   9.7   5.3   24.2  75.5    14.6      M    M
 23000  -30.0 -22.0   225   34   18   8.7   4.8   23.9  75.1    14.6      M    M
 22000  -27.4 -17.3   230   35   18   8.8   4.8   23.5  74.4    14.4      M    M
 21000  -24.7 -12.5   230   37   19   8.9   4.9   23.3  73.9    14.3      M    M
 20000  -22.5  -8.5   235   38   20   6.8   3.7   22.5  72.5    13.8      M    M
 19500  -21.5  -6.7   235   37   19   6.8   3.8   21.9  71.5    13.4      M    M
 19000  -20.5  -4.9   235   36   19   6.8   3.8   21.4  70.5    13.0      M    M
 18500  -19.5  -3.1   240   35   18   6.9   3.8   20.9  69.6    12.7      M    M
 18000  -18.5  -1.3   240   34   18   7.1   3.9   20.4  68.8    12.3      M    M
 17500  -17.3   0.9   240   35   18   7.8   4.3   20.1  68.1    12.1      M    M
 17000  -16.2   2.8   240   37   19   8.1   4.4   19.7  67.5    11.8      M    M
 16500  -15.3   4.5   245   38   20   4.2   2.3   19.1  66.5    11.3      M    M
 16000  -14.6   5.7   245   40   20   4.4   2.4   18.2  64.8    10.6      M    M
 15500  -13.5   7.7   245   35   18   8.0   4.4   17.0  62.7     9.5      M    M
 15000  -12.3   9.9   250   30   16   8.5   4.7   16.8  62.3     9.4      M    M
 14500  -11.0  12.2   250   26   14   8.5   4.7   16.6  62.0     9.3      M    M
 14000   -9.7  14.5   255   22   11   8.5   4.7   16.5  61.6     9.2      M    M
 13500   -8.4  16.9   255   17    9   8.5   4.7   16.2  61.2     9.0      M    M
 13000   -7.2  19.0   255   12    6   8.5   4.7   16.0  60.9     8.9      M    M
 12500   -5.9  21.4   245   11    6   7.8   4.3   15.8  60.4     8.7      M    M
 12000   -4.8  23.4   235   10    5   7.6   4.2   15.5  59.8     8.4      M    M
 11500   -3.7  25.3   210   10    5   7.6   4.2   15.1  59.2     8.1      M    M
 11000   -2.5  27.5   190   11    6   7.6   4.2   14.8  58.6     7.8      M    M
 10500   -1.4  29.5   165   11    6   7.6   4.2   14.4  57.9     7.5      M    M
 10250   -0.9  30.4   160   11    6   7.6   4.2   14.2  57.6     7.4      M    M
 10000   -0.3  31.5   150   12    6   7.6   4.2   14.1  57.3     7.2      M    M
  9750    0.3  32.5   145   12    6   7.5   4.1   13.9  57.0     7.1      M    M
  9500    0.8  33.4   145   12    6   8.1   4.4   13.7  56.7     6.9      M    M
  9250    1.5  34.7   155   12    6   8.7   4.8   13.6  56.5     6.8      M    M
  9000    2.1  35.8   160   13    7   8.5   4.7   13.5  56.4     6.8      M    M
  8750    2.8  37.0   160   11    5   8.6   4.7   13.4  56.2     6.7      M    M
  8500    3.4  38.1   165    8    4   8.5   4.7   13.4  56.0     6.6      M    M
  8250    4.0  39.2   170    6    3   8.5   4.7   13.3  55.9     6.6      M    M
  8000    4.7  40.5   185    4    2   8.5   4.7   13.2  55.7     6.5      M    M
  7750    5.3  41.5   185    6    3   8.5   4.7   13.1  55.5     6.4      M    M
  7500    5.9  42.6   185    8    4   8.5   4.7   13.0  55.4     6.3      M    M
  7250    6.6  43.9   185   10    5   8.6   4.7   12.9  55.2     6.3      M    M
  7000    7.2  45.0   185   12    6   8.5   4.7   12.8  55.0     6.2      M    M
  6750    7.9  46.2   195   14    7   8.8   4.8   12.7  54.8     6.1      M    M
  6500    8.5  47.3   200   16    8   7.6   4.2   12.6  54.7     6.0      M    M
  6250    9.0  48.2   205   19   10   6.5   3.6   12.4  54.2     5.8      M    M
  6000    9.0  48.2   210   22   11 -12.8  -7.0   11.6  52.9     5.1      M    M
  5750    7.3  45.1   205   17    9 -23.4 -12.9    9.2  48.5     2.7      M    M
  5500    6.3  43.3   195   11    6  -4.3  -2.4    7.4  45.3     0.9      M    M

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

           12/25/2014 at 0800 MST          |       12/25/2014 at 1100 MST
                                           |
K index... +18.8  LI... +2.4               | K index... +15.3  LI... +3.3
CAPE... 0.0  CIN... -0.8                   | 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 -54.0 -65.2  250  16  8   3.4   1.8 | -54.3 -65.7  235  20 10   3.4   1.9
 45000 -49.0 -56.2  295   9  5   3.4   1.9 | -49.2 -56.6  240  17  9   3.4   1.9
 40000 -52.1 -61.8  235  55 28  -2.9  -1.6 | -51.6 -60.9  235  45 23  -2.3  -1.3
 38000 -53.4 -64.1  235  74 38   1.9   1.0 | -52.6 -62.7  235  56 29   2.6   1.4
 36000 -52.5 -62.5  230  72 37   1.5   0.8 | -51.2 -60.2  230  60 31   2.2   1.2
 34000 -51.6 -60.9  230  70 36   1.6   0.9 | -49.9 -57.8  230  64 33   2.2   1.2
 32000 -49.6 -57.3  230  64 33   3.9   2.2 | -48.5 -55.3  230  62 32   2.3   1.3
 30000 -47.2 -53.0  235  57 29   3.9   2.2 | -47.1 -52.8  235  59 30   2.4   1.3
 29000 -45.2 -49.4  235  54 28   6.2   3.4 | -46.0 -50.8  235  56 29   5.2   2.8
 28000 -43.4 -46.1  235  51 27   6.1   3.4 | -44.0 -47.2  235  52 27   5.3   2.9
 27000 -41.5 -42.7  235  49 25   6.2   3.4 | -42.4 -44.3  235  48 25   5.3   2.9
 26000 -39.6 -39.3  235  46 24   7.0   3.9 | -40.6 -41.1  235  44 23   8.1   4.5
 25000 -37.5 -35.5  235  41 21   7.0   3.8 | -38.3 -36.9  230  40 20   7.9   4.3
 24000 -35.4 -31.7  235  37 19   7.0   3.8 | -35.9 -32.6  225  35 18   7.9   4.3
 23000 -33.2 -27.8  235  33 17   9.2   5.0 | -33.6 -28.5  220  32 16   7.4   4.0
 22000 -30.5 -22.9  230  31 16   9.0   4.9 | -31.4 -24.5  225  31 16   7.4   4.1
 21000 -27.8 -18.0  225  30 15   8.9   4.9 | -29.2 -20.6  225  31 16   7.5   4.1
 20000 -25.3 -13.5  225  28 14   8.2   4.5 | -26.8 -16.2  230  31 16   8.6   4.7
 19500 -24.1 -11.4  225  27 14   8.2   4.5 | -25.5 -13.9  230  32 16   8.6   4.7
 19000 -22.9  -9.2  225  26 13   8.2   4.5 | -24.3 -11.7  230  33 17   8.6   4.7
 18500 -21.6  -6.9  225  25 13   8.2   4.5 | -23.0  -9.4  235  33 17   8.6   4.7
 18000 -20.4  -4.7  230  24 12   8.0   4.4 | -21.7  -7.1  235  34 17   8.5   4.7
 17500 -19.3  -2.7  230  23 12   7.2   4.0 | -20.5  -4.9  235  34 18   8.0   4.4
 17000 -18.3  -0.9  225  22 11   7.3   4.0 | -19.3  -2.7  235  35 18   8.1   4.5
 16500 -17.2   1.0  225  21 11   6.8   3.7 | -18.1  -0.6  235  35 18   7.3   4.0
 16000 -16.2   2.8  225  20 10   6.8   3.7 | -17.1   1.2  230  34 17   7.3   4.0
 15500 -15.3   4.5  225  19 10   6.8   3.8 | -16.0   3.2  230  33 17   7.1   3.9
 15000 -14.2   6.4  220  18  9   6.9   3.8 | -15.0   5.0  225  30 16   6.9   3.8
 14500 -12.7   9.1  215  16  8   7.3   4.0 | -13.6   7.5  225  27 14   6.0   3.3
 14000 -11.6  11.1  205  15  8   7.4   4.0 | -12.7   9.1  220  23 12   5.9   3.2
 13500 -10.5  13.1  200  14  7   7.3   4.0 | -11.9  10.6  220  20 10   5.4   3.0
 13000  -9.5  14.9  195  12  6   7.2   4.0 | -11.1  12.0  210  16  8   5.2   2.9
 12500  -8.4  16.9  185  11  6   6.8   3.7 | -10.3  13.5  190  12  6   6.0   3.3
 12000  -7.5  18.5  175   9  5   6.4   3.5 |  -9.3  15.3  165  11  6   6.7   3.7
 11500  -6.5  20.3  160   8  4   6.3   3.5 |  -8.3  17.1  140  12  6   6.8   3.7
 11000  -5.6  21.9  145   7  4   6.4   3.5 |  -7.3  18.9  125  11  6   6.9   3.8
 10500  -4.6  23.7  125   7  4   6.8   3.7 |  -6.3  20.7  115  10  5   7.1   3.9
 10250  -4.1  24.6  120   6  3   7.3   4.0 |  -5.7  21.7  105  10  5   7.3   4.0
 10000  -3.6  25.5  105   5  3   6.5   3.6 |  -5.2  22.6  100  10  5   7.3   4.0
  9750  -3.1  26.4  100   5  3   6.1   3.4 |  -4.7  23.5  090   9  5   7.4   4.1
  9500  -2.6  27.3  090   5  3   7.0   3.9 |  -4.1  24.6  085   9  5   7.3   4.0
  9250  -2.1  28.2  080   6  3   8.0   4.4 |  -3.6  25.5  080   9  4   7.7   4.2
  9000  -1.5  29.3  070   6  3   6.8   3.7 |  -3.0  26.6  075   8  4   6.4   3.5
  8750  -1.0  30.2  055   6  3   5.8   3.2 |  -2.6  27.3  070   8  4   5.1   2.8
  8500  -0.6  30.9  050   7  3   6.8   3.7 |  -2.2  28.0  065   8  4   6.1   3.3
  8250  -0.0  32.0  045   7  4   7.6   4.2 |  -1.7  28.9  060   8  4   6.8   3.7
  8000   0.5  32.9  040   8  4   6.1   3.3 |  -1.2  29.8  055   8  4   5.7   3.1
  7750   0.9  33.6  035   9  5   4.2   2.3 |  -0.9  30.4  050   8  4   4.8   2.6
  7500   1.2  34.2  030   9  5   4.8   2.6 |  -0.5  31.1  045   8  4   5.2   2.9
  7250   1.6  34.9  030  10  5   5.4   2.9 |  -0.1  31.8  040   8  4   5.5   3.0
  7000   2.0  35.6  025  11  5   4.9   2.7 |   0.3  32.5  035   8  4   4.6   2.5
  6750   2.3  36.1  020  11  6   2.4   1.3 |   0.6  33.1  030   8  4   2.9   1.6
  6500   2.3  36.1  015  12  6   0.2   0.1 |   0.8  33.4  020   7  4   2.9   1.6
  6250   2.4  36.3  010  12  6   2.6   1.4 |   1.0  33.8  010   7  4   2.1   1.2
  6000   2.5  36.5  360  13  7  -4.8  -2.6 |   1.2  34.2  360   6  3   5.5   3.0
  5750   1.5  34.7  350  10  5 -18.4 -10.1 |   1.9  35.4  360   6  3  12.8   7.0
  5500  -0.1  31.8  330   5  3 -19.2 -10.5 |   2.9  37.2  360   4  2  14.7   8.1

           12/25/2014 at 1400 MST          |       12/25/2014 at 1700 MST
                                           |
K index... +10.8  LI... +4.2               | K index... +8.8  LI... +4.9
CAPE... 0.0  CIN... M                      | CAPE... +3.7  CIN... -0.8
                                           |
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 -54.6 -66.3  245  22 11   3.6   2.0 | -55.4 -67.7  245  21 11   4.0   2.2
 45000 -49.2 -56.6  265  18  9   3.6   2.0 | -49.4 -56.9  255  12  6   4.0   2.2
 40000 -50.0 -58.0  225  40 20  -1.2  -0.6 | -49.3 -56.7  230  53 28  -0.5  -0.3
 38000 -50.6 -59.1  220  50 26   0.6   0.4 | -49.7 -57.5  230  70 36  -2.1  -1.1
 36000 -50.3 -58.5  220  52 27   0.5   0.2 | -50.9 -59.6  225  70 36  -1.9  -1.1
 34000 -50.0 -58.0  225  54 28   0.5   0.3 | -52.0 -61.6  225  69 36  -1.8  -1.0
 32000 -49.1 -56.4  230  57 29   1.9   1.0 | -51.0 -59.8  225  67 35   3.3   1.8
 30000 -48.0 -54.4  230  61 31   2.0   1.1 | -49.0 -56.2  225  65 33   3.4   1.9
 29000 -46.5 -51.7  230  59 30   5.5   3.0 | -47.5 -53.5  225  64 33   6.8   3.7
 28000 -44.9 -48.8  235  55 28   5.5   3.0 | -45.0 -49.0  225  64 33   6.8   3.7
 27000 -43.3 -45.9  235  51 26   5.5   3.0 | -42.9 -45.2  230  64 33   6.8   3.7
 26000 -41.4 -42.5  235  48 25   9.1   5.0 | -40.8 -41.4  230  64 33   8.1   4.5
 25000 -38.8 -37.8  235  49 25   8.7   4.8 | -38.4 -37.1  230  63 33   8.0   4.4
 24000 -36.2 -33.2  235  49 25   8.7   4.8 | -36.0 -32.8  230  62 32   8.0   4.4
 23000 -33.6 -28.5  240  50 26   7.9   4.3 | -33.6 -28.5  235  61 31   8.0   4.4
 22000 -31.2 -24.2  235  48 25   7.9   4.3 | -31.3 -24.3  235  57 29   8.0   4.4
 21000 -28.9 -20.0  235  47 24   7.9   4.3 | -28.9 -20.0  235  53 27   8.0   4.4
 20000 -26.5 -15.7  235  45 23   7.7   4.2 | -26.5 -15.7  235  48 25   7.3   4.0
 19500 -25.4 -13.7  230  43 22   7.8   4.3 | -25.4 -13.7  235  45 23   7.3   4.0
 19000 -24.2 -11.6  230  41 21   7.8   4.3 | -24.3 -11.7  235  42 22   7.3   4.0
 18500 -23.0  -9.4  225  39 20   7.8   4.3 | -23.2  -9.8  230  39 20   7.3   4.0
 18000 -21.9  -7.4  225  37 19   7.7   4.2 | -22.1  -7.8  230  36 18   7.3   4.0
 17500 -20.9  -5.6  225  36 19   6.4   3.5 | -21.1  -6.0  230  33 17   6.4   3.5
 17000 -19.9  -3.8  225  35 18   6.6   3.6 | -20.2  -4.4  230  30 16   6.6   3.6
 16500 -19.0  -2.2  225  35 18   6.3   3.4 | -19.3  -2.7  230  28 15   5.7   3.1
 16000 -18.1  -0.6  230  35 18   6.3   3.5 | -18.5  -1.3  235  28 14   5.7   3.1
 15500 -17.2   1.0  230  35 18   7.1   3.9 | -17.7   0.1  240  27 14   6.8   3.7
 15000 -16.0   3.2  235  34 18   8.0   4.4 | -16.5   2.3  240  27 14   8.0   4.4
 14500 -14.2   6.4  235  33 17   7.5   4.1 | -15.3   4.5  245  27 14   7.9   4.4
 14000 -13.2   8.2  235  29 15   7.3   4.0 | -13.7   7.3  240  25 13   6.9   3.8
 13500 -12.1  10.2  235  26 13   5.4   2.9 | -12.7   9.1  240  24 12   5.1   2.8
 13000 -11.6  11.1  230  21 11   4.1   2.2 | -12.2  10.0  235  19 10   3.8   2.1
 12500 -11.0  12.2  225  17  9   4.2   2.3 | -11.7  10.9  230  15  8   3.0   1.6
 12000 -10.4  13.3  215  12  6   4.4   2.4 | -11.4  11.5  225  11  6   2.1   1.2
 11500  -9.7  14.5  190   9  5   5.4   3.0 | -11.1  12.0  215   8  4   3.8   2.1
 11000  -8.7  16.3  175   8  4   6.6   3.6 | -10.2  13.6  205   6  3   6.0   3.3
 10500  -7.7  18.1  155   7  4   6.8   3.7 |  -9.3  15.3  190   6  3   5.9   3.2
 10250  -7.2  19.0  145   7  4   6.9   3.8 |  -8.9  16.0  170   6  3   5.8   3.2
 10000  -6.7  19.9  140   7  4   7.2   3.9 |  -8.4  16.9  155   6  3   5.7   3.1
  9750  -6.1  21.0  135   8  4   7.4   4.1 |  -8.0  17.6  145   8  4   5.6   3.1
  9500  -5.6  21.9  130  10  5   6.8   3.7 |  -7.6  18.3  135  10  5   5.6   3.1
  9250  -5.1  22.8  125  11  6   6.6   3.6 |  -7.2  19.0  125  11  6   5.9   3.3
  9000  -4.6  23.7  125  12  6   6.0   3.3 |  -6.8  19.8  120  13  7   4.7   2.6
  8750  -4.2  24.4  120  13  7   5.3   2.9 |  -6.6  20.1  115  14  7   3.7   2.0
  8500  -3.8  25.2  120  14  7   5.3   2.9 |  -6.3  20.7  115  14  7   5.1   2.8
  8250  -3.4  25.9  115  14  7   6.4   3.5 |  -5.9  21.4  110  13  7   6.7   3.7
  8000  -3.0  26.6  115  14  7   3.0   1.7 |  -5.5  22.1  105  13  6   3.2   1.8
  7750  -2.9  26.8  115  13  7   4.8   2.6 |  -5.3  22.5  100  12  6   5.1   2.8
  7500  -2.3  27.9  110  12  6   9.8   5.4 |  -4.7  23.5  100  13  6   9.6   5.3
  7250  -1.6  29.1  110  12  6   9.1   5.0 |  -4.0  24.8  100  13  7   8.4   4.6
  7000  -1.0  30.2  105  11  6   8.7   4.7 |  -3.4  25.9  100  13  7   8.6   4.7
  6750  -0.3  31.5  105  10  5   9.4   5.1 |  -2.8  27.0  100  14  7   8.3   4.5
  6500   0.4  32.7  105  10  5  10.5   5.8 |  -2.2  28.0  095  12  6   8.3   4.5
  6250   1.2  34.2  100  10  5  10.5   5.8 |  -1.6  29.1  095  11  6   8.3   4.6
  6000   2.0  35.6  100  10  5   8.9   4.9 |  -1.0  30.2  095  10  5   7.9   4.3
  5750   2.6  36.7  100   9  5  10.9   6.0 |  -0.4  31.3  095   9  5   8.9   4.9
  5500   3.7  38.7  100   8  4  19.1  10.5 |   0.3  32.5  090   7  4  11.7   6.4
________________________________________________________________________________

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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