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586
UXUS97 KBOU 180116
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1916 MDT Thursday, April 17, 2014

This forecast is for Friday, April 18, 2014:

If the trigger temperature of 66.5 F/19.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1153 ft/min (5.9 m/s)
   Maximum height of thermals.................. 18100 ft MSL (12813 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14342 ft MSL (9054 ft AGL)
Thermal soaring outlook for Saturday 04/19..... 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)................ Weak NVA
Potential height of wave....................... 39508 ft MSL (34221 ft AGL)
Wave soaring outlook for Saturday 04/19........ Poor

Remarks...

Sunrise/Sunset.................... 06:17:32 / 19:39:46 MDT
Total possible sunshine........... 13 hr 22 min 14 sec (802 min 14 sec)
Altitude of sun at 12:58:49 MDT... 61.23 degrees

Upper air data from numerical model forecast valid on 04/18/2014 at 0600 MDT

Freezing level.................. 12426 ft MSL (7139 ft AGL)
Convective condensation level... 18012 ft MSL (12725 ft AGL)
Lifted condensation level....... 18246 ft MSL (12959 ft AGL)
Lifted index.................... +0.9
K index......................... +8.9

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  -61.0 -77.8   275   19   10  -0.3  -0.1      M     M       M      M    M
 45000  -61.5 -78.7   280   29   15  -2.2  -1.2      M     M       M      M    M
 40000  -65.4 -85.7   280   42   22  -2.6  -1.4      M     M       M      M    M
 38000  -62.4 -80.3   280   43   22   8.8   4.8      M     M       M      M    M
 36000  -57.2 -71.0   275   42   22   8.7   4.8      M     M       M      M    M
 34000  -52.0 -61.6   275   40   21   8.4   4.6      M     M       M      M    M
 32000  -46.9 -52.4   280   37   19   8.4   4.6      M     M       M      M    M
 30000  -41.1 -42.0   285   35   18   8.9   4.9   34.0  93.2     6.4      M    M
 29000  -38.4 -37.1   285   33   17   8.9   4.9   33.7  92.6     6.2      M    M
 28000  -35.7 -32.3   290   32   17   8.9   4.9   33.4  92.2     6.1      M    M
 27000  -33.1 -27.6   290   30   16   8.6   4.7   33.1  91.6     5.9      M    M
 26000  -30.5 -22.9   295   28   15   8.6   4.7   32.6  90.7     5.6      M    M
 25000  -27.9 -18.2   300   26   14   8.6   4.7   32.2  90.0     5.3      M    M
 24000  -25.4 -13.7   305   25   13   7.5   4.1   31.8  89.2     5.0      M    M
 23000  -23.1  -9.6   305   26   13   7.6   4.2   30.9  87.6     4.4      M    M
 22000  -20.8  -5.4   305   26   14   7.6   4.2   30.2  86.3     3.8      M    M
 21000  -18.7  -1.7   305   26   13   6.2   3.4   29.2  84.6     3.0      M    M
 20000  -16.9   1.6   310   24   12   6.2   3.4   27.9  82.3     2.0      M    M
 19500  -16.0   3.2   310   23   12   6.3   3.4   27.3  81.2     1.4      M    M
 19000  -15.0   5.0   310   23   12   6.2   3.4   26.8  80.2     0.9      M    M
 18500  -14.1   6.6   310   21   11   6.8   3.8   26.2  79.2     0.5      M    M
 18000  -13.1   8.4   305   20   10   6.8   3.7   25.7  78.3    -0.0   1152  5.9
 17500  -12.1  10.2   305   19   10   6.9   3.8   25.2  77.4    -0.5   1107  5.6
 17000  -11.1  12.0   300   18    9   7.0   3.8   24.7  76.5    -0.9   1062  5.4
 16500  -10.0  14.0   295   17    9   7.0   3.8   24.3  75.7    -1.4   1016  5.2
 16000   -9.0  15.8   290   16    8   7.4   4.1   23.8  74.9    -1.8    969  4.9
 15500   -7.3  18.9   285   15    8   7.6   4.1   23.2  73.8    -2.3    898  4.6
 15000   -6.2  20.8   285   14    7   7.9   4.3   22.9  73.2    -2.7    848  4.3
 14500   -5.0  23.0   285   14    7   7.9   4.3   22.6  72.7    -3.0    799  4.1
 14000   -3.8  25.2   290   13    7   8.4   4.6   22.4  72.2    -3.2    747  3.8
 13500   -2.5  27.5   290   13    7   8.4   4.6   22.1  71.8    -3.5    695  3.5
 13000   -1.3  29.7   295   13    7   8.6   4.7   21.9  71.5    -3.7    642  3.3
 12500   -0.0  32.0   300   14    7   8.6   4.7   21.7  71.1    -3.9    589  3.0
 12000    1.2  34.2   305   15    8   8.1   4.4   21.5  70.7    -4.1    537  2.7
 11500    2.4  36.3   305   16    8   8.1   4.4   21.2  70.2    -4.4    487  2.5
 11000    3.6  38.5   305   17    9   7.5   4.1   20.9  69.7    -4.7    437  2.2
 10500    4.7  40.5   305   18    9   8.0   4.4   20.6  69.0    -5.1    389  2.0
 10250    5.2  41.4   305   18    9   5.2   2.9   20.4  68.7    -5.3    365  1.9
 10000    5.5  41.9   305   18    9   5.7   3.1   19.9  67.9    -5.8    349  1.8
  9750    6.2  43.2   300   18    9   8.8   4.8   19.8  67.6    -5.9    324  1.6
  9500    6.8  44.2   300   18    9   8.2   4.5   19.7  67.4    -6.0    298  1.5
  9250    7.4  45.3   300   17    9   7.4   4.1   19.6  67.2    -6.2    272  1.4
  9000    7.9  46.2   300   17    9   7.2   4.0   19.3  66.8    -6.4    250  1.3
  8750    8.5  47.3   300   16    8   8.3   4.5   19.2  66.6    -6.6    225  1.1
  8500    9.1  48.4   300   15    8   8.0   4.4   19.1  66.3    -6.7    199  1.0
  8250    9.6  49.3   295   14    7   7.5   4.1   18.9  66.1    -6.9    174  0.9
  8000   10.2  50.4   295   14    7   6.4   3.5   18.7  65.7    -7.1    152  0.8
  7750   10.6  51.1   295   14    7   5.4   3.0   18.4  65.1    -7.4    131  0.7
  7500   10.9  51.6   295   14    7   3.6   2.0   18.0  64.4    -7.8    113  0.6
  7250   11.1  52.0   290   14    7   1.2   0.7   17.4  63.4    -8.4    101  0.5
  7000   11.1  52.0   290   13    7   0.0   0.0   16.7  62.1    -9.1     93  0.5
  6750   11.2  52.2   285   12    6   1.4   0.8   16.0  60.9    -9.9     84  0.4
  6500   11.1  52.0   280   10    5  -6.7  -3.7   15.2  59.4   -10.7     79  0.4
  6250   10.1  50.2   265    9    4 -15.1  -8.3   13.5  56.3   -12.4    101  0.5
  6000    9.2  48.6   250    8    4  -9.1  -5.0   11.8  53.3   -14.2    123  0.6
  5750    8.4  47.1   235    8    4 -16.6  -9.1   10.3  50.6   -15.7    139  0.7
  5500    5.9  42.6   225    8    4 -49.6 -27.2    7.3  45.1   -18.9    205  1.0

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

           04/18/2014 at 0900 MDT          |       04/18/2014 at 1200 MDT
                                           |
K index... +8.7  LI... +3.4                | K index... +8.8  LI... +1.8
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 -61.4 -78.5  270  20 10   0.1   0.1 | -62.4 -80.3  260  27 14   0.2   0.1
 45000 -61.3 -78.3  275  27 14  -1.9  -1.0 | -62.2 -80.0  260  35 18  -0.9  -0.5
 40000 -64.5 -84.1  280  38 20  -2.1  -1.2 | -63.6 -82.5  260  37 19  -0.8  -0.4
 38000 -61.7 -79.1  275  40 20   8.2   4.5 | -60.5 -76.9  260  38 20   7.8   4.3
 36000 -56.8 -70.2  270  40 21   8.2   4.5 | -55.8 -68.4  260  39 20   7.8   4.3
 34000 -51.9 -61.4  265  39 20   7.8   4.3 | -51.2 -60.2  255  38 20   7.3   4.0
 32000 -46.7 -52.1  265  34 17   7.8   4.3 | -46.3 -51.3  250  35 18   7.3   4.0
 30000 -41.6 -42.9  270  30 15   9.1   5.0 | -41.5 -42.7  245  31 16   8.8   4.8
 29000 -38.9 -38.0  270  29 15   9.1   5.0 | -38.8 -37.8  245  29 15   8.8   4.8
 28000 -36.1 -33.0  275  27 14   9.1   5.0 | -36.2 -33.2  240  26 13   8.8   4.8
 27000 -33.4 -28.1  275  26 13   8.8   4.8 | -33.6 -28.5  240  25 13   8.0   4.4
 26000 -30.8 -23.4  275  25 13   8.8   4.8 | -31.2 -24.2  240  25 13   8.0   4.4
 25000 -28.2 -18.8  275  23 12   8.8   4.8 | -28.8 -19.8  240  24 13   8.0   4.4
 24000 -25.6 -14.1  275  22 11   7.6   4.2 | -26.4 -15.5  240  24 12   8.6   4.7
 23000 -23.3  -9.9  280  22 11   7.7   4.2 | -23.8 -10.8  245  22 12   8.6   4.7
 22000 -21.0  -5.8  285  21 11   7.7   4.2 | -21.2  -6.2  245  21 11   8.6   4.7
 21000 -18.8  -1.8  290  20 10   6.8   3.7 | -18.8  -1.8  250  20 10   7.6   4.2
 20000 -16.7   1.9  290  19 10   6.9   3.8 | -16.5   2.3  250  20 10   7.6   4.2
 19500 -15.7   3.7  290  18  9   6.9   3.8 | -15.4   4.3  255  19 10   7.6   4.2
 19000 -14.7   5.5  290  17  9   6.9   3.8 | -14.2   6.4  255  19 10   7.6   4.2
 18500 -13.7   7.3  285  16  8   6.1   3.3 | -13.1   8.4  255  19 10   7.1   3.9
 18000 -12.8   9.0  280  16  8   6.2   3.4 | -12.1  10.2  260  18 10   7.1   3.9
 17500 -11.9  10.6  280  16  8   6.6   3.6 | -11.1  12.0  260  18  9   6.7   3.7
 17000 -10.9  12.4  275  16  8   6.9   3.8 | -10.1  13.8  260  18  9   6.6   3.6
 16500  -9.3  15.3  270  15  8   7.5   4.1 |  -8.6  16.5  255  17  9   7.1   3.9
 16000  -8.2  17.2  270  14  7   7.7   4.2 |  -7.6  18.3  260  16  8   7.2   3.9
 15500  -7.1  19.2  275  14  7   7.8   4.3 |  -6.5  20.3  260  15  8   7.7   4.2
 15000  -5.9  21.4  275  13  7   8.0   4.4 |  -5.3  22.5  260  14  7   8.4   4.6
 14500  -4.7  23.5  275  13  7   8.1   4.5 |  -4.0  24.8  260  13  7   8.6   4.7
 14000  -3.4  25.9  280  12  6   8.9   4.9 |  -2.6  27.3  265  13  7   9.5   5.2
 13500  -2.1  28.2  285  12  6   8.9   4.9 |  -1.2  29.8  265  13  6   9.4   5.2
 13000  -0.7  30.7  290  12  6   9.2   5.1 |   0.2  32.4  270  13  7   9.7   5.3
 12500   0.6  33.1  290  12  6   9.2   5.1 |   1.6  34.9  270  14  7   9.8   5.4
 12000   2.0  35.6  295  13  7   8.8   4.8 |   3.0  37.4  275  16  8   8.8   4.8
 11500   3.3  37.9  295  14  7   8.9   4.9 |   4.3  39.7  275  18  9   9.0   4.9
 11000   4.5  40.1  295  14  7   7.9   4.4 |   5.6  42.1  280  20 10   8.1   4.4
 10500   5.7  42.3  290  15  8   8.8   4.8 |   6.8  44.2  280  20 10   8.9   4.9
 10250   6.3  43.3  290  16  8   4.8   2.6 |   7.3  45.1  280  21 11   5.3   2.9
 10000   6.5  43.7  290  16  8   5.9   3.2 |   7.6  45.7  280  20 10   6.0   3.3
  9750   7.2  45.0  290  15  8  10.5   5.7 |   8.3  46.9  280  19 10  10.0   5.5
  9500   7.9  46.2  285  15  8   9.7   5.3 |   9.0  48.2  280  18  9   9.2   5.0
  9250   8.6  47.5  285  14  7   7.5   4.1 |   9.6  49.3  280  17  9   7.8   4.3
  9000   9.1  48.4  285  14  7   6.9   3.8 |  10.1  50.2  275  15  8   7.4   4.1
  8750   9.7  49.5  280  13  6   9.0   4.9 |  10.7  51.3  275  14  7   8.7   4.8
  8500  10.4  50.7  280  12  6   8.3   4.5 |  11.4  52.5  270  12  6   8.2   4.5
  8250  11.0  51.8  280  11  6   7.5   4.1 |  11.9  53.4  270  11  6   7.2   3.9
  8000  11.5  52.7  280  11  5   6.4   3.5 |  12.4  54.3  260   9  5   6.4   3.5
  7750  11.9  53.4  280  10  5   6.0   3.3 |  12.9  55.2  250   7  4   6.0   3.3
  7500  12.3  54.1  280  10  5   4.4   2.4 |  13.3  55.9  235   6  3   7.0   3.8
  7250  12.6  54.7  275  10  5   2.3   1.3 |  13.9  57.0  220   6  3   8.7   4.8
  7000  12.7  54.9  270  10  5   1.9   1.0 |  14.5  58.1  210   6  3   9.1   5.0
  6750  12.9  55.2  265   9  5   2.3   1.3 |  15.2  59.4  205   6  3   9.2   5.1
  6500  12.9  55.2  255   8  4  -2.1  -1.1 |  15.9  60.6  200   6  3  10.3   5.6
  6250  12.5  54.5  240   7  4  -5.3  -2.9 |  16.7  62.1  200   5  3  11.2   6.2
  6000  12.1  53.8  225   7  4  -5.2  -2.8 |  17.5  63.5  200   5  3  10.2   5.6
  5750  11.7  53.1  215   8  4  -4.7  -2.6 |  18.3  64.9  200   5  3  12.9   7.1
  5500  11.5  52.7  210   7  4   1.1   0.6 |  19.6  67.3  200   5  2  21.5  11.8

           04/18/2014 at 1500 MDT          |       04/18/2014 at 1800 MDT
                                           |
K index... +10.7  LI... -0.3               | K index... +15.1  LI... -0.7
CAPE... +24.6  CIN... -51.2                | CAPE... +77.4  CIN... -31.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -62.4 -80.3  260  31 16  -0.4  -0.2 | -62.3 -80.1  260  35 18  -0.4  -0.2
 45000 -63.0 -81.4  255  40 20  -0.7  -0.4 | -62.9 -81.2  260  43 22  -0.6  -0.3
 40000 -64.0 -83.2  245  41 21  -0.5  -0.3 | -63.7 -82.7  250  49 25  -0.4  -0.2
 38000 -60.5 -76.9  245  41 21   8.6   4.7 | -60.2 -76.4  250  48 24   8.7   4.8
 36000 -55.4 -67.7  250  40 21   8.6   4.7 | -55.0 -67.0  245  43 22   8.7   4.8
 34000 -49.9 -57.8  250  40 20   7.3   4.0 | -49.5 -57.1  245  40 21   7.4   4.0
 32000 -45.5 -49.9  240  39 20   7.3   4.0 | -45.0 -49.0  240  39 20   7.4   4.1
 30000 -40.8 -41.4  235  36 19   8.1   4.4 | -40.4 -40.7  235  38 20   7.9   4.3
 29000 -38.4 -37.1  230  33 17   8.1   4.4 | -38.0 -36.4  230  37 19   7.9   4.3
 28000 -36.0 -32.8  225  31 16   8.1   4.4 | -35.6 -32.1  225  36 19   7.9   4.3
 27000 -33.5 -28.3  225  29 15   8.2   4.5 | -33.3 -27.9  220  35 18   7.6   4.1
 26000 -31.1 -24.0  225  28 14   8.2   4.5 | -31.0 -23.8  215  34 17   7.6   4.1
 25000 -28.6 -19.5  225  27 14   8.2   4.5 | -28.8 -19.8  215  32 16   7.6   4.2
 24000 -26.2 -15.2  225  25 13   7.0   3.8 | -26.5 -15.7  215  30 15   6.9   3.8
 23000 -24.1 -11.4  230  23 12   7.1   3.9 | -24.4 -11.9  220  27 14   7.0   3.8
 22000 -22.0  -7.6  235  21 11   7.1   3.9 | -22.4  -8.3  225  25 13   7.0   3.9
 21000 -19.7  -3.5  240  20 10   7.9   4.3 | -20.1  -4.2  230  23 12   8.3   4.5
 20000 -17.4   0.7  240  19 10   7.9   4.3 | -17.7   0.1  235  22 12   8.2   4.5
 19500 -16.2   2.8  240  19 10   7.9   4.3 | -16.4   2.5  235  22 11   8.2   4.5
 19000 -15.0   5.0  245  19 10   7.9   4.3 | -15.2   4.6  235  22 11   8.3   4.5
 18500 -13.8   7.2  245  19 10   8.7   4.8 | -14.0   6.8  235  21 11   8.2   4.5
 18000 -12.5   9.5  245  19 10   8.7   4.8 | -12.8   9.0  235  21 11   8.2   4.5
 17500 -11.2  11.8  245  20 10   8.6   4.7 | -11.6  11.1  235  21 11   8.5   4.6
 17000  -9.3  15.3  245  20 10   8.5   4.7 |  -9.6  14.7  235  19 10   8.6   4.7
 16500  -8.0  17.6  245  20 10   8.6   4.7 |  -8.4  16.9  240  19 10   8.7   4.8
 16000  -6.7  19.9  245  20 10   8.6   4.7 |  -7.1  19.2  240  18  9   8.8   4.8
 15500  -5.5  22.1  245  19 10   8.7   4.8 |  -5.8  21.6  240  17  9   8.7   4.8
 15000  -4.2  24.4  250  19 10   8.8   4.8 |  -4.5  23.9  240  17  9   8.7   4.8
 14500  -2.9  26.8  250  19 10   8.7   4.8 |  -3.2  26.2  240  16  8   8.7   4.8
 14000  -1.6  29.1  250  18  9   8.5   4.7 |  -2.0  28.4  240  15  8   8.8   4.8
 13500  -0.4  31.3  250  18  9   8.6   4.7 |  -0.7  30.7  240  14  7   8.7   4.8
 13000   0.8  33.4  250  17  9   7.9   4.3 |   0.6  33.1  240  13  7   9.1   5.0
 12500   2.0  35.6  245  16  8   7.9   4.4 |   1.9  35.4  235  12  6   9.1   5.0
 12000   3.2  37.8  240  14  7   8.6   4.7 |   3.3  37.9  235  11  6   9.2   5.0
 11500   4.4  39.9  235  13  7   8.7   4.7 |   4.7  40.5  230  11  6   9.3   5.1
 11000   5.6  42.1  230  12  6   7.5   4.1 |   6.0  42.8  230  11  5   8.0   4.4
 10500   6.7  44.1  225  11  6   6.6   3.6 |   7.2  45.0  230  10  5   7.1   3.9
 10250   7.3  45.1  220  10  5  11.0   6.0 |   7.8  46.0  230  10  5  11.8   6.5
 10000   8.2  46.8  220  10  5  12.2   6.7 |   8.8  47.8  230  10  5  12.3   6.8
  9750   8.9  48.0  215   9  5   8.6   4.7 |   9.5  49.1  230   9  5   8.0   4.4
  9500   9.6  49.3  215   9  5   9.8   5.4 |  10.1  50.2  230   9  5   9.1   5.0
  9250  10.3  50.5  210   8  4   8.5   4.7 |  10.8  51.4  230   8  4   9.1   5.0
  9000  10.9  51.6  210   8  4   9.0   5.0 |  11.5  52.7  230   8  4   9.8   5.4
  8750  11.7  53.1  210   8  4  10.3   5.7 |  12.2  54.0  230   8  4   9.9   5.4
  8500  12.4  54.3  210   8  4  10.0   5.5 |  13.0  55.4  230   8  4   9.8   5.4
  8250  13.2  55.8  210   8  4  10.5   5.8 |  13.7  56.7  230   7  4  10.8   5.9
  8000  14.0  57.2  210   8  4  10.4   5.7 |  14.5  58.1  230   7  4  10.6   5.8
  7750  14.7  58.5  210   8  4   9.7   5.3 |  15.3  59.5  230   7  4   9.4   5.2
  7500  15.5  59.9  210   8  4   9.9   5.4 |  16.0  60.8  230   7  4   9.6   5.3
  7250  16.2  61.2  210   8  4  10.4   5.7 |  16.7  62.1  230   7  4  10.1   5.5
  7000  17.0  62.6  215   8  4  10.4   5.7 |  17.5  63.5  230   7  3  10.0   5.5
  6750  17.7  63.9  215   8  4   9.1   5.0 |  18.2  64.8  235   7  3   8.7   4.8
  6500  18.4  65.1  215   8  4  10.0   5.5 |  18.8  65.8  235   7  3   9.4   5.1
  6250  19.2  66.6  215   7  4  11.6   6.4 |  19.6  67.3  235   6  3  10.8   5.9
  6000  20.1  68.2  215   7  4  10.5   5.7 |  20.4  68.7  235   6  3  10.4   5.7
  5750  20.9  69.6  215   7  4  11.6   6.3 |  21.1  70.0  235   6  3   9.7   5.3
  5500  21.9  71.4  215   7  3  18.6  10.2 |  21.8  71.2  235   6  3  10.3   5.6
________________________________________________________________________________

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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