Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210034
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1834 MDT Friday, May 20, 2016

This forecast is for Saturday, May 21, 2016:

If the trigger temperature of 74.6 F/23.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1176 ft/min (6.0 m/s)
   Maximum height of thermals.................. 18164 ft MSL (12857 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14464 ft MSL (9157 ft AGL)
Thermal soaring outlook for Sunday 05/22....... Excellent

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)................ Neither
Potential height of wave....................... 21757 ft MSL (16450 ft AGL)
Wave soaring outlook for Sunday 05/22.......... Poor

Remarks...

Sunrise/Sunset.................... 05:39:37 / 20:12:28 MDT
Total possible sunshine........... 14 hr 32 min 51 sec (872 min 51 sec)
Altitude of sun at 12:56:14 MDT... 70.60 degrees

Upper air data from numerical model forecast valid on 05/21/2016 at 0600 MDT

Freezing level.................. 13849 ft MSL (8542 ft AGL)
Convective condensation level... 15593 ft MSL (10286 ft AGL)
Lifted condensation level....... 16632 ft MSL (11325 ft AGL)
Lifted index.................... -3.6
K index......................... +18.8

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  -64.3 -83.7   250   32   16  -0.5  -0.3      M     M       M      M    M
 45000  -64.7 -84.5   250   42   22   2.3   1.3      M     M       M      M    M
 40000  -61.3 -78.3   260   29   15   1.6   0.9      M     M       M      M    M
 38000  -57.5 -71.5   245   28   14   7.0   3.9      M     M       M      M    M
 36000  -53.3 -63.9   230   28   15   7.0   3.9      M     M       M      M    M
 34000  -48.8 -55.8   215   29   15   8.0   4.4      M     M       M      M    M
 32000  -44.0 -47.2   205   30   15   8.0   4.4      M     M       M      M    M
 30000  -39.0 -38.2   200   29   15   8.7   4.8   36.4  97.4     5.2      M    M
 29000  -35.7 -32.3   200   27   14   8.7   4.8   35.8  96.5     4.9      M    M
 28000  -33.1 -27.6   200   26   13   8.7   4.8   35.6  96.0     4.8      M    M
 27000  -30.5 -22.9   200   26   13   8.6   4.7   35.1  95.2     4.5      M    M
 26000  -28.0 -18.4   205   26   13   8.6   4.7   34.6  94.4     4.1      M    M
 25000  -25.4 -13.7   205   27   14   8.6   4.7   34.3  93.7     3.9      M    M
 24000  -22.8  -9.0   205   28   14   8.2   4.5   33.8  92.9     3.6      M    M
 23000  -20.4  -4.7   210   29   15   8.2   4.5   33.2  91.7     3.1      M    M
 22000  -18.0  -0.4   210   31   16   8.2   4.5   32.7  90.8     2.7      M    M
 21000  -15.6   3.9   205   31   16   7.6   4.2   32.0  89.6     2.1      M    M
 20000  -13.3   8.1   205   32   16   7.6   4.2   31.2  88.2     1.5      M    M
 19500  -12.2  10.0   205   32   16   7.6   4.2   30.9  87.6     1.2      M    M
 19000  -11.1  12.0   205   32   16   7.4   4.0   30.5  87.0     0.9      M    M
 18500  -10.1  13.8   205   30   15   6.3   3.5   30.0  86.0     0.4      M    M
 18000   -9.2  15.4   200   28   14   6.5   3.6   29.4  85.0    -0.1   1169  5.9
 17500   -8.2  17.2   200   26   13   6.6   3.6   28.9  84.0    -0.6   1126  5.7
 17000   -7.3  18.9   200   24   12   6.8   3.7   28.4  83.0    -1.2   1083  5.5
 16500   -6.3  20.7   200   21   11   7.4   4.0   27.9  82.1    -1.7   1040  5.3
 16000   -5.1  22.8   205   20   10   8.9   4.9   27.6  81.7    -1.9    988  5.0
 15500   -3.8  25.2   210   19   10   9.1   5.0   27.5  81.5    -2.1    935  4.7
 15000   -2.1  28.2   210   18    9   7.2   4.0   27.0  80.6    -2.6    862  4.4
 14500   -1.1  30.0   215   17    9   7.2   4.0   26.6  79.8    -3.1    817  4.1
 14000   -0.1  31.8   215   16    8   7.3   4.0   26.1  79.1    -3.5    771  3.9
 13500    0.9  33.6   210   14    7   7.3   4.0   25.7  78.3    -4.0    727  3.7
 13000    2.0  35.6   210   12    6   8.7   4.8   25.5  77.8    -4.4    678  3.4
 12500    3.2  37.8   205   10    5   8.6   4.7   25.3  77.5    -4.6    627  3.2
 12000    4.5  40.1   205    8    4   8.8   4.9   25.1  77.2    -4.8    574  2.9
 11500    5.8  42.4   210    6    3   8.9   4.9   25.0  76.9    -5.0    519  2.6
 11000    7.1  44.8   220    5    3   8.2   4.5   24.8  76.6    -5.2    466  2.4
 10500    8.4  47.1   235    5    3   7.5   4.1   24.5  76.2    -5.4    414  2.1
 10250    9.0  48.2   240    5    2  11.0   6.1   24.4  76.0    -5.6    389  2.0
 10000    9.9  49.8   245    5    3  11.5   6.3   24.7  76.4    -5.4    353  1.8
  9750   10.6  51.1   245    5    2   8.2   4.5   24.6  76.3    -5.4    326  1.7
  9500   11.2  52.2   250    5    2   9.3   5.1   24.5  76.1    -5.5    299  1.5
  9250   11.9  53.4   250    5    2   8.1   4.4   24.5  76.0    -5.6    271  1.4
  9000   12.5  54.5   250    4    2   7.8   4.3   24.3  75.7    -5.8    247  1.3
  8750   13.1  55.6   255    4    2   8.4   4.6   24.2  75.5    -5.9    222  1.1
  8500   13.7  56.7   255    4    2   8.4   4.6   24.1  75.3    -6.0    196  1.0
  8250   14.3  57.7   255    4    2   8.0   4.4   24.0  75.1    -6.2    170  0.9
  8000   14.9  58.8   255    4    2   7.0   3.9   23.8  74.8    -6.3    146  0.7
  7750   15.4  59.7   255    4    2   6.7   3.7   23.6  74.4    -6.6    124  0.6
  7500   15.8  60.4   250    4    2   6.2   3.4   23.3  74.0    -6.9    102  0.5
  7250   16.2  61.2   255    4    2   3.5   1.9   23.0  73.3    -7.2     83  0.4
  7000   16.3  61.3   260    4    2   1.3   0.7   22.4  72.3    -7.9     73  0.4
  6750   16.4  61.5   270    3    2   2.3   1.3   21.8  71.2    -8.5     62  0.3
  6500   16.4  61.5   290    3    2  -2.7  -1.5   21.1  70.0    -9.2     54  0.3
  6250   15.9  60.6   290    3    2 -10.1  -5.5   19.8  67.7   -10.6     64  0.3
  6000   15.0  59.0   285    4    2 -10.6  -5.8   18.3  64.9   -12.2     82  0.4
  5750   14.2  57.6   275    4    2 -11.7  -6.4   16.7  62.1   -13.8    100  0.5
  5500   12.8  55.0   250    5    3 -27.6 -15.1   14.7  58.4   -15.9    134  0.7

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

           05/21/2016 at 0900 MDT          |       05/21/2016 at 1200 MDT
                                           |
K index... +14.5  LI... +0.2               | K index... -3.0  LI... -1.1
CAPE... +41.8  CIN... -37.2                | CAPE... +187.7  CIN... -44.2
                                           |
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 -62.6 -80.7  245  34 17  -1.6  -0.9 | -61.9 -79.4  255  37 19  -0.8  -0.5
 45000 -64.4 -83.9  245  43 22   2.2   1.2 | -63.0 -81.4  245  50 26   0.6   0.3
 40000 -61.0 -77.8  250  38 20   1.7   0.9 | -62.1 -79.8  245  51 26  -0.1  -0.1
 38000 -57.1 -70.8  240  34 17   7.3   4.0 | -57.9 -72.2  240  43 22   8.0   4.4
 36000 -52.7 -62.9  225  30 15   7.3   4.0 | -53.1 -63.6  235  34 18   8.0   4.4
 34000 -48.2 -54.8  220  29 15   7.8   4.3 | -48.2 -54.8  230  31 16   8.5   4.7
 32000 -43.5 -46.3  220  28 14   7.8   4.3 | -43.1 -45.6  235  35 18   8.5   4.7
 30000 -37.9 -36.2  215  27 14   8.7   4.8 | -37.3 -35.1  235  35 18   8.9   4.9
 29000 -35.3 -31.5  210  27 14   8.7   4.8 | -34.6 -30.3  235  33 17   8.9   4.9
 28000 -32.6 -26.7  205  28 14   8.8   4.8 | -31.9 -25.4  230  32 17   9.0   4.9
 27000 -30.1 -22.2  205  28 14   8.1   4.4 | -29.5 -21.1  225  31 16   7.4   4.1
 26000 -27.7 -17.9  200  29 15   8.1   4.4 | -27.3 -17.1  215  30 15   7.4   4.1
 25000 -25.3 -13.5  200  30 15   8.1   4.4 | -25.1 -13.2  205  30 15   7.4   4.1
 24000 -23.0  -9.4  200  30 15   7.5   4.1 | -23.0  -9.4  205  30 16   6.6   3.6
 23000 -20.7  -5.3  200  29 15   7.5   4.1 | -21.0  -5.8  205  31 16   6.6   3.6
 22000 -18.4  -1.1  200  28 15   7.5   4.1 | -19.0  -2.2  205  32 16   6.6   3.6
 21000 -16.3   2.7  200  28 14   7.0   3.8 | -16.9   1.6  210  32 16   7.8   4.3
 20000 -14.2   6.4  200  27 14   7.0   3.8 | -14.5   5.9  210  32 16   7.9   4.3
 19500 -13.2   8.2  205  27 14   6.9   3.8 | -13.3   8.1  210  31 16   7.9   4.3
 19000 -12.1  10.2  205  27 14   6.9   3.8 | -12.2  10.0  215  31 16   7.9   4.3
 18500 -11.1  12.0  200  27 14   6.5   3.6 | -11.0  12.2  215  31 16   8.0   4.4
 18000 -10.2  13.6  200  26 14   6.6   3.6 |  -9.8  14.4  215  30 15   8.0   4.4
 17500  -9.2  15.4  195  26 13   6.5   3.6 |  -8.6  16.5  215  29 15   7.8   4.3
 17000  -8.3  17.1  195  25 13   6.6   3.6 |  -7.4  18.7  215  27 14   7.8   4.3
 16500  -7.3  18.9  190  24 12   7.1   3.9 |  -6.3  20.7  210  26 13   7.7   4.2
 16000  -6.1  21.0  190  23 12   8.7   4.8 |  -4.5  23.9  210  24 12   7.7   4.2
 15500  -4.2  24.4  195  22 11   8.4   4.6 |  -3.4  25.9  210  23 12   7.8   4.3
 15000  -3.1  26.4  195  21 11   8.1   4.4 |  -2.2  28.0  210  22 11   8.0   4.4
 14500  -1.9  28.6  195  20 10   8.1   4.4 |  -1.0  30.2  210  22 11   8.0   4.4
 14000  -0.7  30.7  200  19 10   8.0   4.4 |   0.2  32.4  210  21 11   7.7   4.2
 13500   0.4  32.7  200  18  9   8.0   4.4 |   1.3  34.3  205  21 11   7.8   4.3
 13000   1.6  34.9  200  17  9   9.7   5.3 |   2.4  36.3  205  20 10   7.3   4.0
 12500   3.0  37.4  195  15  8   9.7   5.3 |   3.5  38.3  205  20 10   7.3   4.0
 12000   4.3  39.7  190  14  7   8.7   4.8 |   4.6  40.3  205  19 10   8.1   4.4
 11500   5.6  42.1  195  13  7   8.9   4.9 |   5.7  42.3  200  18  9   8.3   4.5
 11000   6.8  44.2  195  12  6   7.3   4.0 |   6.8  44.2  200  17  9   6.6   3.6
 10500   7.9  46.2  195  12  6   6.3   3.4 |   7.7  45.9  190  16  8   5.6   3.1
 10250   8.4  47.1  195  12  6  11.3   6.2 |   8.2  46.8  190  16  8  11.2   6.2
 10000   9.4  48.9  200  11  6  11.8   6.5 |   9.1  48.4  185  15  8  12.6   6.9
  9750  10.0  50.0  200  11  6   7.1   3.9 |   9.7  49.5  185  14  7   7.9   4.4
  9500  10.6  51.1  200  11  5   8.5   4.7 |  10.3  50.5  180  14  7   9.4   5.2
  9250  11.2  52.2  200  10  5   7.6   4.2 |  10.9  51.6  180  13  7   8.5   4.6
  9000  11.8  53.2  200  10  5   8.5   4.7 |  11.6  52.9  180  13  7   9.3   5.1
  8750  12.5  54.5  200   9  5   9.5   5.2 |  12.3  54.1  175  12  6  10.5   5.8
  8500  13.2  55.8  200   9  4   9.4   5.2 |  13.0  55.4  175  12  6  10.1   5.5
  8250  13.9  57.0  195   8  4   8.2   4.5 |  13.7  56.7  175  11  6  10.9   6.0
  8000  14.4  57.9  195   7  4   6.5   3.6 |  14.6  58.3  175  11  6  10.3   5.7
  7750  14.9  58.8  195   7  3   6.4   3.5 |  15.3  59.5  175  10  5   8.9   4.9
  7500  15.3  59.5  190   6  3   5.7   3.1 |  15.9  60.6  175  10  5   9.2   5.0
  7250  15.6  60.1  190   5  3   3.5   1.9 |  16.6  61.9  175  10  5  10.3   5.7
  7000  15.8  60.4  185   4  2   2.1   1.1 |  17.4  63.3  175   9  5  10.8   6.0
  6750  15.9  60.6  180   3  2   1.0   0.6 |  18.2  64.8  170   9  5  10.0   5.5
  6500  15.8  60.4  175   2  1  -0.5  -0.3 |  18.9  66.0  170   9  4  10.2   5.6
  6250  15.7  60.3  185   2  1  -0.6  -0.3 |  19.7  67.5  170   8  4  11.1   6.1
  6000  15.6  60.1  205   1  1  -1.4  -0.8 |  20.6  69.1  170   8  4  10.9   6.0
  5750  15.5  59.9  235   1  1   3.1   1.7 |  21.4  70.5  170   7  4  10.9   6.0
  5500  16.1  61.0  245   1  1  17.0   9.4 |  22.3  72.1  170   7  4  17.5   9.6

           05/21/2016 at 1500 MDT          |       05/21/2016 at 1800 MDT
                                           |
K index... +4.0  LI... +0.9                | K index... +14.8  LI... +1.0
CAPE... 0.0  CIN... -1.6                   | CAPE... +65.1  CIN... -89.4
                                           |
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 -62.7 -80.9  240  36 19  -1.4  -0.7 | -61.6 -78.9  245  36 19  -1.9  -1.0
 45000 -64.4 -83.9  240  52 27   1.4   0.8 | -64.0 -83.2  245  59 31   1.0   0.5
 40000 -62.1 -79.8  250  61 32   0.8   0.4 | -62.5 -80.5  250  65 33   0.2   0.1
 38000 -58.0 -72.4  250  56 29   7.9   4.3 | -58.0 -72.4  250  62 32   8.5   4.6
 36000 -53.2 -63.8  245  49 25   7.9   4.3 | -52.9 -63.2  250  58 30   8.5   4.6
 34000 -48.4 -55.1  245  45 23   8.4   4.6 | -47.8 -54.0  245  56 29   8.5   4.7
 32000 -43.3 -45.9  245  44 23   8.4   4.6 | -42.7 -44.9  245  54 28   8.5   4.7
 30000 -37.4 -35.3  240  42 22   9.1   5.0 | -37.1 -34.8  240  47 24   8.2   4.5
 29000 -34.7 -30.5  240  41 21   9.1   5.0 | -34.6 -30.3  235  42 22   8.2   4.5
 28000 -32.0 -25.6  240  40 21   9.1   5.0 | -32.2 -26.0  225  38 19   8.2   4.5
 27000 -29.3 -20.7  235  37 19   8.7   4.8 | -29.7 -21.5  225  36 18   8.5   4.6
 26000 -26.7 -16.1  235  33 17   8.7   4.8 | -27.1 -16.8  225  35 18   8.5   4.6
 25000 -24.1 -11.4  230  28 15   8.6   4.7 | -24.6 -12.3  225  34 18   8.5   4.6
 24000 -21.8  -7.2  225  27 14   6.2   3.4 | -22.0  -7.6  225  33 17   8.9   4.9
 23000 -19.9  -3.8  225  28 14   6.2   3.4 | -19.3  -2.7  220  32 16   8.9   4.9
 22000 -18.1  -0.6  220  29 15   6.3   3.4 | -16.6   2.1  220  31 16   8.9   4.9
 21000 -15.9   3.4  220  30 16   8.1   4.5 | -14.2   6.4  225  31 16   7.2   4.0
 20000 -13.5   7.7  225  30 15   8.2   4.5 | -12.1  10.2  235  34 17   7.2   3.9
 19500 -12.2  10.0  225  30 16   8.2   4.5 | -11.0  12.2  240  35 18   7.2   3.9
 19000 -11.0  12.2  230  30 16   8.1   4.5 |  -9.9  14.2  240  37 19   7.1   3.9
 18500  -9.9  14.2  230  31 16   7.2   4.0 |  -9.0  15.8  245  37 19   6.0   3.3
 18000  -8.8  16.2  230  31 16   7.3   4.0 |  -8.1  17.4  245  36 18   6.1   3.4
 17500  -7.7  18.1  230  31 16   7.2   3.9 |  -7.2  19.0  245  34 18   6.2   3.4
 17000  -6.7  19.9  225  30 15   7.2   3.9 |  -6.3  20.7  240  31 16   6.3   3.4
 16500  -5.6  21.9  225  28 14   7.4   4.0 |  -5.4  22.3  240  29 15   6.4   3.5
 16000  -3.8  25.2  220  27 14   8.2   4.5 |  -3.9  25.0  230  28 14   7.0   3.8
 15500  -2.6  27.3  220  26 13   7.6   4.2 |  -2.9  26.8  220  28 15   7.4   4.0
 15000  -1.6  29.1  210  24 12   6.6   3.6 |  -1.8  28.8  215  28 15   8.1   4.5
 14500  -0.7  30.7  205  23 12   6.8   3.7 |  -0.6  30.9  210  29 15   8.2   4.5
 14000   0.3  32.5  195  22 11   7.3   4.0 |   0.7  33.3  205  29 15   9.6   5.3
 13500   1.3  34.3  190  21 11   7.4   4.0 |   2.1  35.8  200  29 15   9.6   5.3
 13000   2.5  36.5  185  20 10   9.9   5.4 |   3.4  38.1  195  29 15   9.4   5.2
 12500   3.9  39.0  180  20 10   9.7   5.3 |   4.8  40.6  195  29 15   9.4   5.2
 12000   5.3  41.5  180  20 10   9.6   5.3 |   6.2  43.2  195  29 15   9.4   5.1
 11500   6.7  44.1  180  19 10   9.7   5.3 |   7.6  45.7  195  29 15   9.4   5.2
 11000   8.1  46.6  180  19 10   9.0   5.0 |   9.0  48.2  195  29 15   8.8   4.8
 10500   9.4  48.9  180  19 10   9.2   5.1 |  10.3  50.5  190  29 15   8.9   4.9
 10250  10.2  50.4  180  19 10  11.7   6.4 |  11.0  51.8  190  29 15  10.5   5.8
 10000  11.1  52.0  180  19 10  11.1   6.1 |  11.8  53.2  190  29 15  10.4   5.7
  9750  11.8  53.2  180  19 10   9.1   5.0 |  12.5  54.5  185  29 15   9.3   5.1
  9500  12.5  54.5  180  19 10   9.6   5.2 |  13.2  55.8  185  28 15   9.7   5.3
  9250  13.3  55.9  180  19 10   9.7   5.3 |  13.9  57.0  185  28 14   9.1   5.0
  9000  14.0  57.2  180  19 10   9.9   5.4 |  14.6  58.3  185  28 14   9.1   5.0
  8750  14.7  58.5  180  18 10  10.0   5.5 |  15.3  59.5  185  27 14   9.7   5.3
  8500  15.5  59.9  180  18  9   9.5   5.2 |  16.0  60.8  185  27 14   8.9   4.9
  8250  16.2  61.2  180  18  9  11.4   6.2 |  16.7  62.1  185  27 14  11.4   6.3
  8000  17.1  62.8  180  18  9  11.3   6.2 |  17.6  63.7  185  27 14  11.4   6.3
  7750  17.8  64.0  180  18  9   9.1   5.0 |  18.3  64.9  185  26 14   8.8   4.8
  7500  18.5  65.3  180  18  9   9.3   5.1 |  19.0  66.2  180  26 13   9.0   4.9
  7250  19.2  66.6  180  18  9  10.5   5.7 |  19.6  67.3  180  26 13  10.0   5.5
  7000  20.1  68.2  180  17  9  11.0   6.1 |  20.4  68.7  180  25 13  10.8   5.9
  6750  20.8  69.4  180  17  9   9.1   5.0 |  21.2  70.2  180  25 13   9.5   5.2
  6500  21.5  70.7  180  17  9   9.2   5.0 |  21.9  71.4  180  24 13   9.2   5.1
  6250  22.2  72.0  180  17  9  10.9   6.0 |  22.6  72.7  180  24 12  10.2   5.6
  6000  23.1  73.6  180  16  8  12.0   6.6 |  23.4  74.1  180  22 11  10.9   6.0
  5750  23.9  75.0  180  16  8   9.7   5.3 |  24.1  75.4  180  21 11   9.8   5.3
  5500  24.7  76.5  180  15  8  12.9   7.1 |  24.8  76.6  180  18  9   9.0   4.9
________________________________________________________________________________

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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