Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220105
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1905 MDT Saturday, May 21, 2016

This forecast is for Sunday, May 22, 2016:

If the trigger temperature of 69.4 F/20.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 475 ft/min (2.4 m/s)
   Maximum height of thermals.................. 13762 ft MSL (8455 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 0945 MDT
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................. 10903 ft MSL (5596 ft AGL)
Thermal soaring outlook for Monday 05/23....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 24715 ft MSL (19408 ft AGL)
Wave soaring outlook for Monday 05/23.......... Fair

Remarks...

Sunrise/Sunset.................... 05:38:54 / 20:13:20 MDT
Total possible sunshine........... 14 hr 34 min 26 sec (874 min 26 sec)
Altitude of sun at 12:56:19 MDT... 70.79 degrees

Upper air data from numerical model forecast valid on 05/22/2016 at 0600 MDT

Freezing level.................. 13834 ft MSL (8527 ft AGL)
Convective condensation level... 18184 ft MSL (12877 ft AGL)
Lifted condensation level....... 16906 ft MSL (11600 ft AGL)
Lifted index.................... +2.1
K index......................... -3.1

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  -62.2 -80.0   245   24   12  -3.6  -2.0      M     M       M      M    M
 45000  -66.8 -88.2   225   38   20   4.5   2.5      M     M       M      M    M
 40000  -60.4 -76.7   240   56   29   3.6   2.0      M     M       M      M    M
 38000  -56.2 -69.2   235   55   28   7.4   4.1      M     M       M      M    M
 36000  -51.8 -61.2   230   53   27   7.4   4.1      M     M       M      M    M
 34000  -47.1 -52.8   220   51   26   8.0   4.4      M     M       M      M    M
 32000  -42.3 -44.1   215   48   25   8.0   4.4      M     M       M      M    M
 30000  -37.3 -35.1   205   46   24   8.9   4.9   38.7 101.6     9.9      M    M
 29000  -34.0 -29.2   205   45   23   8.9   4.9   38.2 100.8     9.7      M    M
 28000  -31.3 -24.3   205   44   23   8.9   4.9   38.0 100.4     9.7      M    M
 27000  -28.9 -20.0   210   45   23   7.7   4.2   37.4  99.3     9.3      M    M
 26000  -26.6 -15.9   210   46   24   7.7   4.2   36.6  97.8     8.8      M    M
 25000  -24.3 -11.7   215   48   25   7.7   4.2   35.9  96.5     8.3      M    M
 24000  -22.0  -7.6   215   48   25   6.9   3.8   35.0  95.1     7.7      M    M
 23000  -19.9  -3.8   215   47   24   7.0   3.8   34.0  93.1     6.9      M    M
 22000  -17.8  -0.0   215   46   23   7.0   3.8   33.0  91.4     6.2      M    M
 21000  -15.8   3.6   215   44   22   6.9   3.8   32.0  89.7     5.4      M    M
 20000  -13.7   7.3   210   41   21   6.9   3.8   31.0  87.8     4.6      M    M
 19500  -12.7   9.1   210   40   20   6.9   3.8   30.5  86.9     4.2      M    M
 19000  -11.7  10.9   210   38   20   6.8   3.7   30.0  86.1     3.8      M    M
 18500  -10.6  12.9   205   38   19   8.4   4.6   29.7  85.5     3.5      M    M
 18000   -9.3  15.3   205   37   19   8.3   4.5   29.4  85.0     3.3      M    M
 17500   -8.1  17.4   205   37   19   8.0   4.4   29.2  84.6     3.1      M    M
 17000   -6.9  19.6   205   37   19   7.9   4.3   28.9  84.0     2.8      M    M
 16500   -5.7  21.7   205   37   19   7.8   4.3   28.6  83.4     2.6      M    M
 16000   -4.6  23.7   200   37   19   7.1   3.9   28.2  82.7     2.2      M    M
 15500   -3.0  26.6   200   36   18   7.0   3.9   27.5  81.5     1.7      M    M
 15000   -2.0  28.4   200   35   18   6.6   3.6   27.0  80.6     1.2      M    M
 14500   -1.0  30.2   200   34   17   6.7   3.7   26.5  79.7     0.7      M    M
 14000   -0.1  31.8   205   33   17   6.0   3.3   25.9  78.7     0.2      M    M
 13500    0.7  33.3   210   33   17   6.2   3.4   25.3  77.6    -0.4    646  3.3
 13000    1.6  34.9   220   33   17   6.5   3.6   24.8  76.6    -1.0    605  3.1
 12500    2.5  36.5   225   33   17   6.6   3.6   24.2  75.6    -1.6    564  2.9
 12000    3.4  38.1   225   32   17   7.3   4.0   23.8  74.8    -2.1    521  2.6
 11500    4.5  40.1   230   30   16   7.5   4.1   23.4  74.1    -2.5    474  2.4
 11000    5.6  42.1   235   28   15   6.4   3.5   23.0  73.4    -2.9    428  2.2
 10500    6.5  43.7   235   26   13   5.5   3.0   22.4  72.4    -3.5    386  2.0
 10250    6.9  44.4   240   25   13   8.4   4.6   22.1  71.8    -3.8    365  1.9
 10000    7.6  45.7   240   23   12   8.5   4.7   22.1  71.8    -3.8    337  1.7
  9750    8.1  46.6   240   21   11   5.7   3.1   21.9  71.3    -4.1    316  1.6
  9500    8.5  47.3   240   19   10   6.2   3.4   21.6  70.8    -4.4    294  1.5
  9250    9.0  48.2   240   17    9   7.0   3.9   21.3  70.4    -4.7    273  1.4
  9000    9.6  49.3   245   15    8   8.4   4.6   21.2  70.1    -4.8    248  1.3
  8750   10.2  50.4   240   13    7   8.4   4.6   21.1  69.9    -4.9    222  1.1
  8500   10.8  51.4   240   12    6   8.1   4.4   21.0  69.7    -5.1    197  1.0
  8250   11.4  52.5   240   10    5   9.4   5.2   20.9  69.5    -5.2    171  0.9
  8000   12.2  54.0   240    9    5  10.1   5.6   20.9  69.6    -5.2    140  0.7
  7750   12.9  55.2   240    8    4   8.7   4.8   20.9  69.5    -5.2    112  0.6
  7500   13.5  56.3   240    7    4   8.5   4.7   20.8  69.4    -5.3     86  0.4
  7250   14.2  57.6   240    6    3   8.4   4.6   20.7  69.2    -5.4     59  0.3
  7000   14.8  58.6   240    5    3   7.7   4.2   20.5  69.0    -5.6     34  0.2
  6750   15.3  59.5   245    5    2   7.0   3.8   20.4  68.7    -5.8     10  0.0
  6500   15.8  60.4   250    4    2   3.3   1.8   20.0  68.1    -6.1      M    M
  6250   15.7  60.3   245    5    3  -4.2  -2.3   19.3  66.7    -6.8      M    M
  6000   15.2  59.4   235    6    3  -7.1  -3.9   18.1  64.5    -8.1      M    M
  5750   14.6  58.3   230    8    4  -9.2  -5.0   16.8  62.2    -9.5      2  0.0
  5500   13.3  55.9   220   11    6 -29.0 -15.9   14.8  58.6   -11.5     34  0.2

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

           05/22/2016 at 0900 MDT          |       05/22/2016 at 1200 MDT
                                           |
K index... -9.9  LI... +4.9                | K index... +6.2  LI... +3.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -61.8 -79.2  250  18  9  -3.1  -1.7 | -62.0 -79.6  260  18  9  -2.9  -1.6
 45000 -65.6 -86.1  230  33 17   3.3   1.8 | -65.5 -85.9  240  32 16   3.6   2.0
 40000 -60.4 -76.7  230  54 28   3.1   1.7 | -59.7 -75.5  230  59 30   3.6   2.0
 38000 -56.2 -69.2  230  55 28   7.7   4.2 | -55.8 -68.4  225  60 31   7.2   4.0
 36000 -51.6 -60.9  225  55 29   7.7   4.2 | -51.4 -60.5  225  60 31   7.2   4.0
 34000 -46.9 -52.4  220  55 28   7.9   4.4 | -46.9 -52.4  225  59 30   7.9   4.3
 32000 -42.2 -44.0  215  53 27   7.9   4.4 | -42.2 -44.0  220  58 30   7.9   4.3
 30000 -36.8 -34.2  215  51 26   8.2   4.5 | -37.0 -34.6  220  57 29   7.6   4.2
 29000 -34.3 -29.7  210  50 26   8.2   4.5 | -34.7 -30.5  220  56 29   7.6   4.2
 28000 -31.9 -25.4  210  49 25   8.2   4.5 | -32.4 -26.3  220  56 29   7.6   4.2
 27000 -29.5 -21.1  210  49 25   8.0   4.4 | -30.1 -22.2  220  55 28   8.0   4.4
 26000 -27.1 -16.8  215  49 25   8.0   4.4 | -27.7 -17.9  220  54 28   8.0   4.4
 25000 -24.7 -12.5  215  49 25   8.0   4.4 | -25.3 -13.5  220  54 28   8.1   4.4
 24000 -22.4  -8.3  215  49 25   7.2   3.9 | -22.9  -9.2  220  53 27   7.6   4.2
 23000 -20.2  -4.4  215  48 25   7.2   4.0 | -20.6  -5.1  220  53 27   7.7   4.2
 22000 -18.0  -0.4  215  47 24   7.2   4.0 | -18.3  -0.9  220  52 27   7.7   4.2
 21000 -15.9   3.4  215  46 24   7.1   3.9 | -16.1   3.0  215  51 26   7.2   3.9
 20000 -13.8   7.2  215  46 23   7.1   3.9 | -14.0   6.8  215  49 25   7.2   4.0
 19500 -12.7   9.1  215  45 23   7.1   3.9 | -12.9   8.8  215  49 25   7.2   4.0
 19000 -11.7  10.9  210  45 23   7.1   3.9 | -11.8  10.8  215  48 25   7.2   3.9
 18500 -10.6  12.9  210  45 23   7.5   4.1 | -10.7  12.7  215  47 24   7.6   4.2
 18000  -9.5  14.9  210  44 23   7.5   4.1 |  -9.6  14.7  215  47 24   7.6   4.2
 17500  -8.4  16.9  205  43 22   7.6   4.2 |  -8.4  16.9  215  46 24   7.7   4.2
 17000  -7.2  19.0  205  42 22   7.9   4.3 |  -7.3  18.9  215  45 23   7.9   4.3
 16500  -6.0  21.2  200  41 21   7.9   4.3 |  -6.1  21.0  215  44 23   7.9   4.3
 16000  -4.3  24.3  200  39 20   7.4   4.1 |  -4.3  24.3  220  43 22   7.9   4.3
 15500  -3.2  26.2  200  37 19   7.3   4.0 |  -3.2  26.2  220  43 22   7.8   4.3
 15000  -2.1  28.2  200  35 18   7.2   3.9 |  -2.1  28.2  220  43 22   6.4   3.5
 14500  -1.1  30.0  205  33 17   7.3   4.0 |  -1.2  29.8  225  43 22   6.7   3.7
 14000  -0.0  32.0  210  32 16   6.4   3.5 |  -0.4  31.3  225  41 21   4.2   2.3
 13500   0.9  33.6  215  31 16   6.4   3.5 |   0.2  32.4  230  38 19   4.2   2.3
 13000   1.9  35.4  220  30 16   6.6   3.6 |   0.8  33.4  230  33 17   3.8   2.1
 12500   2.9  37.2  230  29 15   6.6   3.6 |   1.3  34.3  225  27 14   3.7   2.0
 12000   3.8  38.8  235  28 14   5.5   3.0 |   1.9  35.4  225  22 11   5.4   3.0
 11500   4.5  40.1  240  27 14   5.1   2.8 |   2.8  37.0  215  18  9   6.4   3.5
 11000   5.2  41.4  245  26 14   3.4   1.8 |   3.8  38.8  200  15  8   7.0   3.8
 10500   5.5  41.9  245  22 11   2.2   1.2 |   4.8  40.6  190  14  7   6.8   3.7
 10250   5.7  42.3  245  20 10   4.2   2.3 |   5.4  41.7  185  13  7  10.0   5.5
 10000   6.1  43.0  240  17  9   6.8   3.7 |   6.2  43.2  185  12  6  11.2   6.1
  9750   6.5  43.7  240  15  8   6.6   3.6 |   6.9  44.4  180  12  6   8.8   4.8
  9500   7.0  44.6  235  13  7   6.7   3.7 |   7.6  45.7  180  12  6   9.5   5.2
  9250   7.4  45.3  230  11  6   6.6   3.6 |   8.3  46.9  180  11  6   9.3   5.1
  9000   7.9  46.2  225  10  5   7.6   4.2 |   9.0  48.2  180  11  6   9.6   5.3
  8750   8.5  47.3  215   9  5   8.4   4.6 |   9.7  49.5  180  11  6   9.8   5.4
  8500   9.1  48.4  210   8  4   8.0   4.4 |  10.4  50.7  180  11  5   9.6   5.3
  8250   9.7  49.5  200   7  4   8.8   4.8 |  11.2  52.2  180  10  5  10.3   5.7
  8000  10.4  50.7  190   7  4   9.3   5.1 |  12.0  53.6  180  10  5  10.4   5.7
  7750  11.0  51.8  185   7  3   8.6   4.7 |  12.7  54.9  180  10  5   9.5   5.2
  7500  11.7  53.1  175   6  3   8.4   4.6 |  13.4  56.1  180  10  5   9.0   4.9
  7250  12.3  54.1  170   6  3   8.2   4.5 |  14.1  57.4  180   9  5  10.3   5.7
  7000  12.9  55.2  165   6  3   7.8   4.3 |  14.9  58.8  180   9  5  11.4   6.2
  6750  13.4  56.1  160   5  3   6.5   3.5 |  15.7  60.3  180   9  5   9.4   5.1
  6500  13.8  56.8  160   5  2   5.7   3.2 |  16.4  61.5  180   9  4   8.8   4.8
  6250  14.3  57.7  165   4  2   6.6   3.6 |  17.1  62.8  185   8  4  10.8   5.9
  6000  14.7  58.5  175   4  2   6.9   3.8 |  18.0  64.4  185   8  4  12.3   6.8
  5750  15.2  59.4  185   3  2   7.0   3.8 |  18.8  65.8  185   7  4  10.0   5.5
  5500  15.7  60.3  190   3  1  12.0   6.6 |  19.6  67.3  185   7  4  14.6   8.0

           05/22/2016 at 1500 MDT          |       05/22/2016 at 1800 MDT
                                           |
K index... +19.5  LI... +1.7               | K index... +23.2  LI... -1.7
CAPE... 0.0  CIN... M                      | CAPE... +88.4  CIN... -22.0
                                           |
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 -60.9 -77.6  260  16  8  -1.7  -0.9 | -60.8 -77.4  250  20 10  -0.9  -0.5
 45000 -62.9 -81.2  245  27 14   2.0   1.1 | -61.9 -79.4  240  34 17   1.9   1.0
 40000 -59.7 -75.5  230  61 31   2.0   1.1 | -59.0 -74.2  230  58 30   2.0   1.1
 38000 -55.9 -68.6  225  63 32   7.4   4.1 | -55.4 -67.7  230  61 31   7.1   3.9
 36000 -51.4 -60.5  225  62 32   7.4   4.1 | -51.2 -60.2  230  61 31   7.1   3.9
 34000 -46.8 -52.2  220  62 32   8.1   4.4 | -46.7 -52.1  230  61 31   7.9   4.3
 32000 -41.3 -42.3  225  61 31   8.1   4.4 | -41.4 -42.5  230  60 31   7.9   4.3
 30000 -36.6 -33.9  225  60 31   7.6   4.1 | -36.7 -34.1  230  58 30   7.9   4.3
 29000 -34.4 -29.9  225  59 31   7.6   4.1 | -34.3 -29.7  235  57 29   7.9   4.3
 28000 -32.1 -25.8  220  59 30   7.6   4.1 | -32.0 -25.6  235  56 29   7.8   4.3
 27000 -29.8 -21.6  220  58 30   7.6   4.2 | -29.7 -21.5  235  55 28   6.9   3.8
 26000 -27.6 -17.7  225  58 30   7.6   4.2 | -27.7 -17.9  235  55 28   6.9   3.8
 25000 -25.3 -13.5  225  58 30   7.6   4.2 | -25.6 -14.1  235  54 28   7.0   3.8
 24000 -23.0  -9.4  225  58 30   8.3   4.5 | -23.6 -10.5  235  54 28   5.7   3.1
 23000 -20.5  -4.9  225  57 30   8.2   4.5 | -21.9  -7.4  240  53 27   5.6   3.1
 22000 -18.1  -0.6  230  57 29   8.2   4.5 | -20.3  -4.5  240  52 27   5.7   3.1
 21000 -15.8   3.6  230  57 29   5.9   3.2 | -18.5  -1.3  245  50 26   7.0   3.8
 20000 -14.0   6.8  230  55 28   6.1   3.3 | -16.5   2.3  240  42 22   6.9   3.8
 19500 -13.1   8.4  235  54 28   6.1   3.3 | -15.5   4.1  240  39 20   6.9   3.8
 19000 -12.2  10.0  235  53 28   6.2   3.4 | -14.5   5.9  240  35 18   6.9   3.8
 18500 -11.4  11.5  235  52 27   4.7   2.6 | -13.4   7.9  240  32 17   8.2   4.5
 18000 -10.8  12.6  235  49 25   4.6   2.5 | -12.2  10.0  235  31 16   8.4   4.6
 17500 -10.1  13.8  235  46 23   4.9   2.7 | -11.0  12.2  230  30 15   8.4   4.6
 17000  -9.3  15.3  235  42 21   5.8   3.2 |  -9.8  14.4  230  29 15   8.3   4.6
 16500  -8.1  17.4  235  35 18   6.3   3.5 |  -7.9  17.8  220  28 15   8.5   4.7
 16000  -7.1  19.2  230  31 16   7.3   4.0 |  -6.6  20.1  220  27 14   8.8   4.8
 15500  -6.0  21.2  220  28 14   7.3   4.0 |  -5.3  22.5  215  27 14   8.7   4.8
 15000  -4.9  23.2  215  25 13   8.4   4.6 |  -4.0  24.8  210  26 13   9.1   5.0
 14500  -3.6  25.5  210  23 12   8.3   4.5 |  -2.7  27.1  210  25 13   9.0   5.0
 14000  -2.4  27.7  200  21 11   9.3   5.1 |  -1.3  29.7  205  25 13   9.5   5.2
 13500  -1.0  30.2  200  20 10   9.3   5.1 |   0.1  32.2  205  24 12   9.6   5.3
 13000   0.4  32.7  200  19 10   9.4   5.2 |   1.6  34.9  205  23 12   9.6   5.2
 12500   1.8  35.2  195  19 10   9.5   5.2 |   3.0  37.4  205  22 11   9.6   5.2
 12000   3.2  37.8  195  18  9   9.7   5.3 |   4.4  39.9  205  21 11   9.4   5.2
 11500   4.7  40.5  195  18  9   9.9   5.4 |   5.8  42.4  205  19 10   9.3   5.1
 11000   6.2  43.2  195  17  9   9.3   5.1 |   7.2  45.0  205  18  9   9.1   5.0
 10500   7.5  45.5  195  17  9   8.4   4.6 |   8.5  47.3  205  16  8   8.8   4.8
 10250   8.2  46.8  195  16  8  11.4   6.2 |   9.2  48.6  205  15  8   9.9   5.4
 10000   9.1  48.4  195  16  8  11.9   6.5 |   9.9  49.8  205  14  7  10.1   5.5
  9750   9.9  49.8  195  16  8   9.6   5.3 |  10.6  51.1  205  12  6   9.1   5.0
  9500  10.6  51.1  195  15  8  10.5   5.8 |  11.3  52.3  210  11  6   9.6   5.2
  9250  11.4  52.5  200  15  8   9.0   4.9 |  12.0  53.6  210   9  5   8.6   4.7
  9000  12.0  53.6  200  15  8   9.0   4.9 |  12.6  54.7  215   9  4   8.2   4.5
  8750  12.8  55.0  200  14  7  10.4   5.7 |  13.2  55.8  220   7  4   9.0   4.9
  8500  13.5  56.3  200  14  7   9.7   5.3 |  13.9  57.0  230   6  3   8.4   4.6
  8250  14.3  57.7  200  14  7  11.0   6.0 |  14.5  58.1  240   6  3   9.9   5.4
  8000  15.1  59.2  200  14  7  10.7   5.9 |  15.3  59.5  255   5  3  10.6   5.8
  7750  15.9  60.6  200  13  7   9.1   5.0 |  16.0  60.8  265   5  2   8.9   4.9
  7500  16.5  61.7  200  13  7   8.7   4.8 |  16.7  62.1  280   5  3   8.4   4.6
  7250  17.2  63.0  200  13  7  10.0   5.5 |  17.3  63.1  290   5  3   8.7   4.8
  7000  18.0  64.4  200  13  6  11.4   6.2 |  18.0  64.4  295   6  3   9.3   5.1
  6750  18.8  65.8  200  12  6  10.1   5.6 |  18.7  65.7  300   6  3   9.8   5.4
  6500  19.5  67.1  205  12  6   9.0   4.9 |  19.4  66.9  305   6  3   9.8   5.4
  6250  20.3  68.5  205  12  6  10.6   5.8 |  20.2  68.4  305   7  3  10.0   5.5
  6000  21.1  70.0  205  11  6  12.2   6.7 |  20.9  69.6  310   7  3  10.3   5.7
  5750  22.0  71.6  205  11  5  10.9   6.0 |  21.6  70.9  310   7  4  10.4   5.7
  5500  22.9  73.2  205  10  5  15.8   8.7 |  22.5  72.5  315   7  4  13.1   7.2
________________________________________________________________________________

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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