Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 131303
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0602 MST Saturday, December 13, 2014

This forecast is for Saturday, December 13, 2014:

If the trigger temperature of 68.1 F/20.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 6700 ft MSL (1415 ft AGL)

Forecast maximum temperature................... 59.0 F/15.5 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6043 ft MSL (758 ft AGL)
Thermal soaring outlook for Sunday 12/14....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Up
Height of stable layer (12-18K ft MSL)......... 3200 ft MSL (-2085 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 39051 ft MSL (33766 ft AGL)
Wave soaring outlook for Sunday 12/14.......... Poor

Remarks...

Sunrise/Sunset.................... 07:12:01 / 16:35:34 MST
Total possible sunshine........... 9 hr 23 min 33 sec (563 min 33 sec)
Altitude of sun at 11:53:50 MST... 27.12 degrees

Upper air data from rawinsonde observation taken on 12/13/2014 at 0500 MST

Freezing level.................. 13618 ft MSL (8333 ft AGL)
Convective condensation level... 22334 ft MSL (17049 ft AGL)
Lifted condensation level....... 16344 ft MSL (11059 ft AGL)
Lifted index.................... +11.1
K index......................... -13.1

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  -63.5 -82.3   220   38   20   3.9   2.1   92.3 198.1    44.3      M    M
 45000  -64.3 -83.7   205   21   11   5.2   2.9   66.4 151.5    31.6      M    M
 40000  -63.8 -82.8   205   54   28   0.1   0.0   44.0 111.3    19.2      M    M
 38000  -60.7 -77.3   190   57   29   8.5   4.6   39.8 103.7    16.8      M    M
 36000  -55.6 -68.1   190   53   27   8.4   4.6   38.6 101.6    16.5      M    M
 34000  -50.3 -58.5   190   51   26  10.0   5.5   38.1 100.6    16.5      M    M
 32000  -44.0 -47.2   190   52   27   9.2   5.1   37.5  99.5    16.6      M    M
 30000  -39.0 -38.2   185   50   26   7.5   4.1   36.6  97.9    16.3      M    M
 29000  -36.7 -34.1   185   49   25   7.5   4.1   35.6  96.1    15.7      M    M
 28000  -34.5 -30.1   185   48   25   7.5   4.1   34.7  94.5    15.3      M    M
 27000  -32.2 -26.0   190   47   24   8.7   4.8   34.0  93.3    14.9      M    M
 26000  -29.6 -21.3   190   46   24   8.7   4.8   33.6  92.5    14.7      M    M
 25000  -27.0 -16.6   190   45   23   8.8   4.8   33.3  91.9    14.5      M    M
 24000  -24.5 -12.1   190   43   22   8.1   4.4   32.7  90.8    14.2      M    M
 23000  -22.2  -8.0   190   43   22   8.2   4.5   32.1  89.7    13.8      M    M
 22000  -19.9  -3.8   185   43   22   7.4   4.1   31.3  88.3    13.3      M    M
 21000  -17.7   0.1   185   44   23   7.5   4.1   30.5  86.8    12.7      M    M
 20000  -15.4   4.3   185   44   23   7.5   4.1   29.8  85.6    12.2      M    M
 19500  -14.2   6.4   185   42   22   7.2   3.9   29.5  85.1    12.1      M    M
 19000  -13.0   8.6   185   40   21   8.5   4.7   29.1  84.3    11.8      M    M
 18500  -12.2  10.0   185   39   20   5.4   3.0   28.2  82.8    11.2      M    M
 18000  -11.0  12.2   185   37   19   7.9   4.4   27.9  82.3    11.1      M    M
 17500   -9.7  14.5   185   36   19   8.7   4.8   27.7  81.8    11.0      M    M
 17000   -8.4  16.9   185   35   18   5.2   2.8   27.4  81.4    10.9      M    M
 16500   -7.8  18.0   190   32   16   5.7   3.1   26.5  79.7    10.1      M    M
 16000   -6.4  20.5   200   27   14   8.3   4.6   25.7  78.2     9.4      M    M
 15500   -5.0  23.0   205   26   13   9.0   4.9   25.5  77.9     9.3      M    M
 15000   -3.6  25.5   205   25   13   9.1   5.0   25.4  77.7     9.3      M    M
 14500   -2.2  28.0   210   25   13   9.2   5.0   25.3  77.6     9.3      M    M
 14000   -0.8  30.6   210   24   12   9.4   5.1   25.3  77.5     9.3      M    M
 13500    0.6  33.1   210   22   11   9.4   5.1   25.2  77.3     9.3      M    M
 13000    2.0  35.6   210   20   10   9.6   5.3   25.1  77.2     9.3      M    M
 12500    3.2  37.8   210   19   10   6.7   3.7   24.9  76.8     9.1      M    M
 12000    4.2  39.6   210   16    8   6.8   3.7   24.4  76.0     8.7      M    M
 11500    5.2  41.4   205   12    6   6.8   3.7   24.0  75.1     8.3      M    M
 11000    6.3  43.3   195    8    4   7.0   3.9   23.5  74.3     7.9      M    M
 10500    7.1  44.8   190   10    5   5.0   2.7   22.9  73.2     7.4      M    M
 10250    7.5  45.5   190   11    6   5.1   2.8   22.5  72.6     7.0      M    M
 10000    7.8  46.0   190   12    6   2.5   1.4   22.1  71.8     6.6      M    M
  9750    7.9  46.2   200   12    6   0.9   0.5   21.4  70.6     5.9      M    M
  9500    7.9  46.2   205   12    6   1.0   0.6   20.8  69.4     5.3      M    M
  9250    8.1  46.6   210   13    6   5.5   3.0   20.2  68.3     4.7      M    M
  9000    8.7  47.7   215   13    7   9.5   5.2   20.1  68.2     4.7      M    M
  8750    9.4  48.9   215   11    5   8.1   4.5   20.0  68.0     4.6      M    M
  8500   10.0  50.0   210    8    4   9.6   5.3   19.9  67.8     4.5      M    M
  8250   10.6  51.1   210    6    3   2.7   1.5   19.8  67.6     4.4      M    M
  8000   10.4  50.7   200    4    2  -3.3  -1.8   18.9  65.9     3.5      M    M
  7750   10.2  50.4   190    5    3  -2.1  -1.1   17.9  64.3     2.6      M    M
  7500   10.1  50.2   185    6    3  -0.9  -0.5   17.0  62.7     1.7      M    M
  7250   10.2  50.4   185    7    4   3.0   1.6   16.4  61.5     1.0      M    M
  7000   10.4  50.7   180    8    4   3.4   1.9   15.9  60.6     0.6      M    M
  6750   10.7  51.3   185    6    3   5.4   2.9   15.5  59.8     0.1      M    M
  6500   11.0  51.8   190    5    3  -2.9  -1.6   15.0  59.0    -0.3    108  0.5
  6250   10.2  50.4   200    3    2 -10.2  -5.6   13.6  56.4    -1.8    123  0.6
  6000    9.7  49.5   220    2    1  -4.9  -2.7   12.3  54.1    -3.1    132  0.7
  5750    9.4  48.9   200    2    1  -1.0  -0.6   11.3  52.4    -4.1    132  0.7
  5500    8.9  48.0   180    2    1 -22.8 -12.5   10.0  50.0    -5.4    141  0.7

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

           12/13/2014 at 0800 MST          |       12/13/2014 at 1100 MST
                                           |
K index... +1.0  LI... +5.0                | K index... +0.6  LI... +5.6
CAPE... 0.0  CIN... M                      | 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 -64.8 -84.6  220  26 13   1.9   1.0 | -63.3 -81.9  215  32 16   1.4   0.7
 45000 -62.0 -79.6  205  36 19  -0.1  -0.1 | -61.2 -78.2  195  44 23   0.7   0.4
 40000 -61.9 -79.4  205  65 33   0.0   0.0 | -60.2 -76.4  205  65 34   0.6   0.4
 38000 -59.2 -74.6  205  66 34   6.9   3.8 | -57.9 -72.2  200  69 35   5.7   3.1
 36000 -55.1 -67.2  200  63 33   6.9   3.8 | -54.5 -66.1  195  70 36   5.7   3.1
 34000 -50.5 -58.9  195  60 31   8.7   4.8 | -50.7 -59.3  185  70 36   7.8   4.3
 32000 -44.6 -48.3  190  56 29   8.8   4.8 | -45.4 -49.7  185  64 33   7.9   4.3
 30000 -39.5 -39.1  185  54 28   8.2   4.5 | -40.5 -40.9  185  61 31   8.7   4.8
 29000 -37.1 -34.8  180  54 28   8.2   4.5 | -37.8 -36.0  180  62 32   8.7   4.8
 28000 -34.6 -30.3  180  54 28   8.2   4.5 | -35.2 -31.4  180  63 32   8.7   4.8
 27000 -32.2 -26.0  180  54 28   7.5   4.1 | -32.7 -26.9  180  63 32   7.5   4.1
 26000 -29.9 -21.8  180  53 27   7.6   4.2 | -30.4 -22.7  180  62 32   7.6   4.2
 25000 -27.7 -17.9  185  53 27   7.6   4.2 | -28.2 -18.8  185  61 31   7.6   4.2
 24000 -25.4 -13.7  185  52 27   7.9   4.3 | -25.9 -14.6  185  60 31   7.9   4.3
 23000 -23.0  -9.4  185  51 26   7.9   4.4 | -23.5 -10.3  185  55 28   8.0   4.4
 22000 -20.6  -5.1  185  50 26   8.0   4.4 | -21.1  -6.0  185  50 26   8.0   4.4
 21000 -18.3  -0.9  190  48 25   6.1   3.4 | -18.8  -1.8  185  46 23   6.1   3.4
 20000 -16.4   2.5  190  44 23   6.3   3.5 | -17.0   1.4  190  42 21   6.0   3.3
 19500 -15.5   4.1  190  43 22   6.3   3.5 | -16.1   3.0  190  40 20   6.0   3.3
 19000 -14.5   5.9  190  41 21   6.3   3.5 | -15.2   4.6  190  38 19   6.0   3.3
 18500 -13.6   7.5  190  39 20   6.5   3.6 | -14.3   6.3  195  36 18   5.4   2.9
 18000 -12.6   9.3  190  37 19   6.5   3.6 | -13.5   7.7  195  33 17   4.9   2.7
 17500 -11.6  11.1  195  35 18   6.6   3.6 | -12.8   9.0  195  30 15   4.9   2.7
 17000 -10.6  12.9  190  33 17   6.8   3.7 | -11.9  10.6  200  27 14   6.6   3.6
 16500  -9.6  14.7  190  31 16   6.8   3.7 | -11.0  12.2  200  26 13   6.5   3.6
 16000  -8.6  16.5  190  29 15   6.6   3.6 | -10.0  14.0  200  24 12   6.9   3.8
 15500  -7.1  19.2  190  25 13   6.6   3.6 |  -8.4  16.9  205  22 11   6.9   3.8
 15000  -6.0  21.2  195  22 11   8.1   4.5 |  -7.3  18.9  205  21 11   7.8   4.3
 14500  -4.8  23.4  195  20 10   8.1   4.4 |  -6.2  20.8  210  19 10   7.8   4.3
 14000  -3.7  25.3  200  18  9   7.2   4.0 |  -5.0  23.0  215  18  9   7.5   4.1
 13500  -2.6  27.3  205  17  9   7.2   3.9 |  -3.9  25.0  220  17  9   7.4   4.1
 13000  -1.5  29.3  215  17  9   7.6   4.1 |  -2.9  26.8  225  16  8   6.9   3.8
 12500  -0.4  31.3  215  14  7   7.7   4.2 |  -1.9  28.6  230  12  6   6.6   3.6
 12000   0.7  33.3  220  11  6   6.3   3.4 |  -1.0  30.2  235   9  5   6.7   3.7
 11500   1.5  34.7  225   6  3   5.5   3.0 |   0.0  32.0  230   6  3   6.9   3.8
 11000   2.2  36.0  240   2  1   5.5   3.0 |   1.1  34.0  230   3  1   7.0   3.9
 10500   3.1  37.6  315   2  1   4.9   2.7 |   2.1  35.8  205   1  1   6.4   3.5
 10250   3.5  38.3  335   2  1   8.1   4.5 |   2.7  36.9  150   1  0  10.3   5.6
 10000   4.2  39.6  340   3  2   9.0   4.9 |   3.6  38.5  095   1  1  10.1   5.6
  9750   4.7  40.5  340   4  2   6.3   3.5 |   4.1  39.4  080   2  1   6.2   3.4
  9500   5.2  41.4  340   4  2   7.1   3.9 |   4.6  40.3  075   3  2   7.3   4.0
  9250   5.7  42.3  340   5  3   6.7   3.7 |   5.1  41.2  075   4  2   7.0   3.9
  9000   6.2  43.2  340   6  3   6.3   3.4 |   5.6  42.1  070   4  2   7.3   4.0
  8750   6.7  44.1  335   6  3   6.2   3.4 |   6.2  43.2  070   4  2   7.5   4.1
  8500   7.1  44.8  335   6  3   6.0   3.3 |   6.7  44.1  070   4  2   7.3   4.0
  8250   7.6  45.7  330   7  3   7.0   3.8 |   7.3  45.1  070   4  2   7.8   4.3
  8000   8.1  46.6  330   7  4   8.4   4.6 |   7.9  46.2  065   3  2   8.3   4.5
  7750   8.7  47.7  330   8  4   8.2   4.5 |   8.4  47.1  060   3  2   7.5   4.1
  7500   9.3  48.7  330   8  4   8.3   4.5 |   9.0  48.2  055   3  1   7.6   4.2
  7250   9.9  49.8  330   8  4   7.1   3.9 |   9.5  49.1  050   3  1   6.4   3.5
  7000  10.4  50.7  325  10  5   5.6   3.1 |   9.9  49.8  035   3  1   4.8   2.7
  6750  10.7  51.3  325  11  6   4.6   2.5 |  10.2  50.4  025   3  2   3.8   2.1
  6500  10.9  51.6  320  12  6  -1.1  -0.6 |  10.4  50.7  010   3  1   2.1   1.1
  6250  10.5  50.9  315  11  6  -9.0  -5.0 |  10.5  50.9  360   2  1   0.4   0.2
  6000   9.7  49.5  305   9  5 -11.3  -6.2 |  10.5  50.9  320   1  0  -0.2  -0.1
  5750   9.0  48.2  285   7  4  -8.4  -4.6 |  10.5  50.9  230   1  1  -1.6  -0.9
  5500   7.9  46.2  260   7  4 -28.8 -15.8 |  10.3  50.5  215   3  2  -1.1  -0.6

           12/13/2014 at 1400 MST          |       12/13/2014 at 1700 MST
                                           |
K index... +7.1  LI... +3.8                | K index... +10.5  LI... +3.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.0 -79.6  220  33 17   0.9   0.5 | -60.9 -77.6  235  31 16   0.7   0.4
 45000 -60.5 -76.9  210  49 25   1.5   0.8 | -59.7 -75.5  220  48 25   2.1   1.1
 40000 -58.1 -72.6  200  57 29   1.6   0.9 | -56.1 -69.0  200  47 24   2.4   1.3
 38000 -56.5 -69.7  190  61 31   3.5   1.9 | -54.7 -66.5  195  51 26   2.4   1.3
 36000 -54.4 -65.9  185  67 35   3.5   1.9 | -53.2 -63.8  185  58 30   2.4   1.3
 34000 -51.7 -61.1  180  72 37   8.6   4.7 | -51.4 -60.5  180  65 34   7.7   4.2
 32000 -46.6 -51.9  180  69 36   8.5   4.6 | -47.1 -52.8  175  69 35   7.2   3.9
 30000 -40.9 -41.6  180  67 35   8.6   4.7 | -42.1 -43.8  175  71 37   8.3   4.5
 29000 -38.3 -36.9  180  67 34   8.6   4.7 | -39.6 -39.3  175  70 36   8.3   4.5
 28000 -35.7 -32.3  185  67 34   8.6   4.7 | -37.2 -35.0  180  68 35   8.3   4.5
 27000 -33.2 -27.8  185  67 34   7.5   4.1 | -34.7 -30.5  180  67 34   7.2   3.9
 26000 -31.1 -24.0  190  66 34   7.2   4.0 | -32.9 -27.2  185  61 32   6.2   3.4
 25000 -28.9 -20.0  190  64 33   7.2   4.0 | -31.0 -23.8  190  56 29   6.2   3.4
 24000 -26.8 -16.2  190  63 32   6.8   3.7 | -29.2 -20.6  200  52 27   6.3   3.5
 23000 -24.9 -12.8  190  60 31   6.1   3.4 | -27.0 -16.6  200  49 25   7.3   4.0
 22000 -23.1  -9.6  195  56 29   6.1   3.4 | -24.9 -12.8  200  45 23   7.3   4.0
 21000 -21.3  -6.3  195  52 27   6.5   3.6 | -22.7  -8.9  205  42 21   7.3   4.0
 20000 -19.2  -2.6  195  47 24   6.7   3.7 | -20.5  -4.9  205  37 19   7.2   3.9
 19500 -18.2  -0.8  200  45 23   6.7   3.7 | -19.5  -3.1  205  35 18   7.2   3.9
 19000 -17.2   1.0  200  42 22   6.7   3.7 | -18.4  -1.1  210  33 17   7.2   3.9
 18500 -16.2   2.8  200  39 20   6.8   3.7 | -17.3   0.9  210  31 16   6.9   3.8
 18000 -15.2   4.6  200  35 18   6.8   3.7 | -16.3   2.7  210  28 14   6.4   3.5
 17500 -14.2   6.4  200  32 16   6.9   3.8 | -15.4   4.3  210  25 13   6.3   3.4
 17000 -13.2   8.2  205  28 15   6.1   3.4 | -14.4   6.1  205  23 12   7.6   4.2
 16500 -12.3   9.9  205  26 13   6.2   3.4 | -13.3   8.1  205  22 11   7.6   4.2
 16000 -11.3  11.7  205  23 12   7.3   4.0 | -12.1  10.2  205  21 11   7.4   4.1
 15500 -10.2  13.6  205  21 11   7.9   4.3 | -11.1  12.0  200  19 10   7.2   3.9
 15000  -8.4  16.9  205  18  9   8.1   4.5 |  -9.5  14.9  195  17  9   7.9   4.4
 14500  -7.2  19.0  210  17  9   8.2   4.5 |  -8.3  17.1  200  16  8   8.1   4.4
 14000  -6.0  21.2  210  16  8   8.1   4.4 |  -7.1  19.2  200  15  8   7.3   4.0
 13500  -4.8  23.4  215  14  7   8.0   4.4 |  -6.1  21.0  200  13  7   6.6   3.6
 13000  -3.6  25.5  220  13  7   6.9   3.8 |  -5.2  22.6  205  11  6   6.6   3.6
 12500  -2.8  27.0  220  10  5   5.8   3.2 |  -4.2  24.4  195   9  5   6.6   3.6
 12000  -1.9  28.6  215   7  4   6.3   3.5 |  -3.2  26.2  185   7  3   7.1   3.9
 11500  -0.9  30.4  190   4  2   7.4   4.0 |  -2.1  28.2  150   6  3   8.3   4.6
 11000   0.2  32.4  135   4  2   7.4   4.1 |  -0.8  30.6  120   7  4   7.9   4.3
 10500   1.3  34.3  110   7  3   7.4   4.0 |   0.2  32.4  105   9  5   6.4   3.5
 10250   1.9  35.4  100   8  4   7.8   4.3 |   0.7  33.3  100  11  6   8.0   4.4
 10000   2.5  36.5  095  10  5   8.6   4.7 |   1.4  34.5  095  13  7   9.5   5.2
  9750   3.1  37.6  095  11  6   8.7   4.7 |   2.1  35.8  090  14  7   8.6   4.7
  9500   3.8  38.8  095  11  6   8.8   4.9 |   2.7  36.9  090  15  8   8.3   4.6
  9250   4.4  39.9  090  12  6   8.0   4.4 |   3.3  37.9  090  16  8   8.4   4.6
  9000   4.9  40.8  090  13  7   7.4   4.1 |   3.9  39.0  085  17  9   8.2   4.5
  8750   5.5  41.9  090  13  7   7.9   4.3 |   4.5  40.1  085  17  9   8.0   4.4
  8500   6.1  43.0  090  12  6   7.6   4.2 |   5.1  41.2  085  17  9   7.9   4.3
  8250   6.7  44.1  085  12  6   8.4   4.6 |   5.7  42.3  085  17  9   8.5   4.6
  8000   7.4  45.3  085  11  6   8.9   4.9 |   6.4  43.5  085  17  9   9.2   5.0
  7750   8.0  46.4  085  11  5   7.2   3.9 |   7.1  44.8  080  16  8   7.9   4.3
  7500   8.5  47.3  085  10  5   6.4   3.5 |   7.6  45.7  080  15  8   7.0   3.8
  7250   8.9  48.0  085   9  5   6.2   3.4 |   8.2  46.8  080  14  7   7.2   4.0
  7000   9.4  48.9  085   9  4   5.4   3.0 |   8.7  47.7  080  13  7   7.1   3.9
  6750   9.7  49.5  080   8  4   4.3   2.4 |   9.2  48.6  085  11  6   6.2   3.4
  6500  10.0  50.0  080   7  3   4.1   2.2 |   9.6  49.3  085   9  5   5.6   3.1
  6250  10.4  50.7  075   6  3   7.8   4.3 |  10.0  50.0  085   7  4   6.6   3.6
  6000  11.0  51.8  070   5  2  10.0   5.5 |  10.5  50.9  075   5  3   7.0   3.8
  5750  11.7  53.1  065   4  2   8.8   4.8 |  10.9  51.6  065   4  2   7.0   3.9
  5500  12.4  54.3  065   3  2   9.7   5.3 |  11.3  52.3  050   4  2   1.7   0.9
________________________________________________________________________________

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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