Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230130
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1930 MDT Saturday, August 22, 2015

This forecast is for Sunday, August 23, 2015:

If the trigger temperature of 67.7 F/19.9 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 354 ft/min (1.8 m/s)
   Maximum height of thermals.................. 11699 ft MSL (6392 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 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................. 10540 ft MSL (5233 ft AGL)
Thermal soaring outlook for Monday 08/24....... 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....................... 17132 ft MSL (11825 ft AGL)
Wave soaring outlook for Monday 08/24.......... Poor

Remarks... Smoke below 14000 msl

Sunrise/Sunset.................... 06:18:51 / 19:45:59 MDT
Total possible sunshine........... 13 hr 27 min 8 sec (807 min 8 sec)
Altitude of sun at 13:02:01 MDT... 61.58 degrees

Upper air data from numerical model forecast valid on 08/23/2015 at 0600 MDT

Freezing level.................. 15624 ft MSL (10317 ft AGL)
Convective condensation level... 15425 ft MSL (10118 ft AGL)
Lifted condensation level....... 14031 ft MSL (8725 ft AGL)
Lifted index.................... +0.4
K index......................... +20.9

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  -63.7 -82.7   290   33   17   1.9   1.1      M     M       M      M    M
 45000  -59.6 -75.3   285   46   24   4.6   2.5      M     M       M      M    M
 40000  -52.6 -62.7   280   43   22   5.3   2.9      M     M       M      M    M
 38000  -49.4 -56.9   280   39   20   5.4   2.9      M     M       M      M    M
 36000  -46.1 -51.0   275   35   18   5.2   2.8      M     M       M      M    M
 34000  -40.9 -41.6   275   31   16   8.2   4.5      M     M       M      M    M
 32000  -36.0 -32.8   275   28   14   8.3   4.5      M     M       M      M    M
 30000  -31.1 -24.0   280   26   13   8.1   4.4   44.8 112.7    13.4      M    M
 29000  -28.7 -19.7   280   25   13   8.1   4.4   44.2 111.6    13.1      M    M
 28000  -26.3 -15.3   280   24   12   7.9   4.3   43.7 110.6    12.8      M    M
 27000  -24.0 -11.2   280   24   12   7.8   4.3   42.8 109.0    12.3      M    M
 26000  -21.6  -6.9   280   24   13   7.8   4.3   42.1 107.7    11.8      M    M
 25000  -19.3  -2.7   280   25   13   7.8   4.3   41.5 106.7    11.5      M    M
 24000  -17.0   1.4   285   24   13   7.6   4.2   40.6 105.1    10.9      M    M
 23000  -14.7   5.5   290   24   12   7.6   4.2   39.8 103.7    10.4      M    M
 22000  -12.4   9.7   300   25   13   7.2   3.9   39.2 102.5    10.0      M    M
 21000  -10.5  13.1   295   23   12   6.2   3.4   37.9 100.2     8.9      M    M
 20000   -8.7  16.3   290   22   11   6.3   3.4   36.6  98.0     8.0      M    M
 19500   -7.8  18.0   290   22   11   6.4   3.5   36.1  96.9     7.5      M    M
 19000   -6.9  19.6   285   21   11   5.4   3.0   35.4  95.8     7.0      M    M
 18500   -6.1  21.0   285   21   11   5.5   3.0   34.7  94.4     6.3      M    M
 18000   -5.3  22.5   280   21   11   5.9   3.2   34.0  93.2     5.7      M    M
 17500   -4.0  24.8   280   23   12   6.6   3.6   33.1  91.6     4.9      M    M
 17000   -3.1  26.4   280   24   12   7.4   4.1   32.6  90.6     4.3      M    M
 16500   -1.9  28.6   280   24   12   8.3   4.6   32.3  90.1     4.1      M    M
 16000   -0.7  30.7   275   23   12   8.4   4.6   32.1  89.7     3.8      M    M
 15500    0.6  33.1   275   23   12   9.2   5.0   31.9  89.4     3.6      M    M
 15000    1.9  35.4   275   23   12   9.2   5.1   31.8  89.2     3.5      M    M
 14500    3.1  37.6   275   22   11   8.5   4.7   31.7  89.0     3.3      M    M
 14000    4.4  39.9   275   21   11   8.5   4.6   31.4  88.6     3.1      M    M
 13500    5.6  42.1   270   20   11   6.7   3.7   31.2  88.1     2.9      M    M
 13000    6.4  43.5   270   20   10   5.8   3.2   30.5  86.9     2.2      M    M
 12500    7.2  45.0   265   20   10   4.8   2.6   29.9  85.8     1.6      M    M
 12000    7.6  45.7   260   19   10   3.7   2.0   28.9  84.0     0.5      M    M
 11500    8.1  46.6   250   19   10   2.8   1.5   27.9  82.3    -0.5    340  1.7
 11000    8.2  46.8   245   18    9   1.1   0.6   26.6  79.9    -1.8    321  1.6
 10500    8.3  46.9   240   18    9   0.2   0.1   25.3  77.5    -3.2    303  1.5
 10250    8.2  46.8   240   18    9  -1.5  -0.8   24.4  75.9    -4.0    299  1.5
 10000    8.1  46.6   235   17    9  -0.8  -0.5   23.5  74.4    -4.9    295  1.5
  9750    8.0  46.4   230   17    9  -0.5  -0.3   22.7  72.9    -5.7    290  1.5
  9500    7.9  46.2   225   16    8  -0.3  -0.2   21.9  71.5    -6.5    285  1.4
  9250    7.9  46.2   225   15    8   0.1   0.1   21.2  70.1    -7.2    277  1.4
  9000    7.9  46.2   220   14    7   0.1   0.0   20.4  68.7    -8.0    270  1.4
  8750    8.0  46.4   215   13    7   0.0   0.0   19.7  67.4    -8.7    262  1.3
  8500    8.1  46.6   210   12    6   3.4   1.9   19.0  66.2    -9.4    251  1.3
  8250    8.5  47.3   205   11    6   5.9   3.3   18.7  65.6    -9.7    231  1.2
  8000    8.9  48.0   195   10    5   5.6   3.1   18.3  65.0   -10.0    210  1.1
  7750    9.4  48.9   190   10    5   6.4   3.5   18.1  64.5   -10.2    188  1.0
  7500   10.0  50.0   180   10    5   6.0   3.3   17.8  64.0   -10.5    165  0.8
  7250   10.4  50.7   175   11    6   5.7   3.1   17.5  63.5   -10.8    143  0.7
  7000   10.9  51.6   165   12    6   5.6   3.1   17.2  62.9   -11.0    122  0.6
  6750   11.4  52.5   160   13    7   7.0   3.8   16.9  62.4   -11.3    100  0.5
  6500   12.0  53.6   155   13    7   8.2   4.5   16.8  62.2   -11.5     74  0.4
  6250   12.6  54.7   150   12    6   8.1   4.4   16.6  61.9   -11.6     49  0.3
  6000   13.2  55.8   145   12    6   7.5   4.1   16.5  61.7   -11.8     24  0.1
  5750   13.6  56.5   140   11    6   5.1   2.8   16.3  61.3   -12.1      3  0.0
  5500   13.8  56.8   135    8    4   3.0   1.6   15.8  60.5   -12.6      M    M

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

           08/23/2015 at 0900 MDT          |       08/23/2015 at 1200 MDT
                                           |
K index... +15.6  LI... +1.7               | K index... +4.2  LI... +0.9
CAPE... 0.0  CIN... -4.0                   | CAPE... +34.5  CIN... -162.7
                                           |
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 -63.7 -82.7  290  32 16   2.1   1.2 | -63.9 -83.0  290  31 16   2.6   1.4
 45000 -59.3 -74.7  285  42 21   4.6   2.5 | -58.8 -73.8  290  39 20   5.2   2.8
 40000 -52.4 -62.3  280  38 19   5.1   2.8 | -50.9 -59.6  280  35 18   4.0   2.2
 38000 -49.3 -56.7  275  35 18   5.1   2.8 | -48.6 -55.5  275  31 16   4.0   2.2
 36000 -46.2 -51.2  275  31 16   4.9   2.7 | -46.2 -51.2  270  28 14   4.0   2.2
 34000 -41.1 -42.0  270  28 14   8.1   4.4 | -41.4 -42.5  265  25 13   8.4   4.6
 32000 -36.2 -33.2  270  25 13   8.4   4.6 | -36.4 -33.5  265  23 12   8.3   4.6
 30000 -31.4 -24.5  270  24 12   8.0   4.4 | -31.7 -25.1  260  22 12   7.7   4.2
 29000 -29.0 -20.2  265  23 12   8.0   4.4 | -29.4 -20.9  260  22 12   7.7   4.2
 28000 -26.6 -15.9  265  22 12   8.0   4.4 | -26.5 -15.7  260  22 11   7.8   4.3
 27000 -24.2 -11.6  270  22 11   8.1   4.4 | -24.2 -11.6  265  21 11   7.8   4.3
 26000 -21.8  -7.2  270  21 11   8.1   4.4 | -21.9  -7.4  270  20 11   7.8   4.3
 25000 -19.4  -2.9  270  21 11   7.9   4.3 | -19.5  -3.1  275  20 10   7.7   4.2
 24000 -17.2   1.0  275  20 10   7.3   4.0 | -17.3   0.9  280  19 10   7.6   4.1
 23000 -15.0   5.0  285  19 10   7.3   4.0 | -15.0   5.0  285  19 10   7.6   4.2
 22000 -12.8   9.0  295  19 10   7.4   4.1 | -12.8   9.0  285  18  9   7.6   4.2
 21000 -10.5  13.1  290  20 10   7.6   4.2 | -10.5  13.1  285  19 10   7.6   4.2
 20000  -8.3  17.1  290  21 11   7.6   4.2 |  -8.3  17.1  285  19 10   7.6   4.2
 19500  -7.1  19.2  290  21 11   7.8   4.3 |  -7.1  19.2  280  20 10   7.6   4.2
 19000  -6.1  21.0  290  21 11   6.1   3.4 |  -6.0  21.2  280  20 10   7.0   3.8
 18500  -5.2  22.6  290  21 11   6.3   3.4 |  -5.0  23.0  280  20 10   7.0   3.9
 18000  -4.2  24.4  285  21 11   6.3   3.5 |  -3.9  25.0  285  19 10   7.3   4.0
 17500  -2.8  27.0  285  21 11   6.3   3.5 |  -2.8  27.0  285  20 10   7.5   4.1
 17000  -1.9  28.6  285  21 11   6.5   3.6 |  -1.7  28.9  285  20 10   7.5   4.1
 16500  -1.0  30.2  285  21 11   6.7   3.7 |  -0.6  30.9  285  20 10   7.4   4.1
 16000   0.0  32.0  280  22 11   6.8   3.7 |   0.5  32.9  285  20 10   7.4   4.1
 15500   1.0  33.8  280  22 11   7.9   4.3 |   1.6  34.9  290  20 10   7.5   4.1
 15000   2.1  35.8  280  23 12   7.8   4.3 |   3.3  37.9  290  21 11   7.6   4.2
 14500   3.3  37.9  280  23 12   8.9   4.9 |   4.3  39.7  290  22 11   7.1   3.9
 14000   4.6  40.3  280  22 12   9.0   4.9 |   5.3  41.5  290  23 12   7.2   4.0
 13500   5.9  42.6  280  22 11   8.3   4.5 |   6.4  43.5  290  23 12   7.5   4.1
 13000   7.0  44.6  280  21 11   7.9   4.3 |   7.4  45.3  290  23 12   7.7   4.2
 12500   8.1  46.6  280  20 10   6.4   3.5 |   8.5  47.3  290  23 12   7.6   4.2
 12000   8.8  47.8  275  18  9   4.9   2.7 |   9.5  49.1  290  21 11   7.5   4.1
 11500   9.4  48.9  275  16  8   3.8   2.1 |  10.5  50.9  290  19 10   5.7   3.1
 11000   9.6  49.3  265  15  8   2.1   1.2 |  11.0  51.8  285  16  8   4.0   2.2
 10500   9.8  49.6  255  13  7   1.4   0.8 |  11.6  52.9  285  13  7   2.3   1.2
 10250   9.8  49.6  250  13  7  -0.3  -0.2 |  11.6  52.9  285  13  7   0.1   0.1
 10000   9.7  49.5  245  13  7  -0.8  -0.4 |  11.6  52.9  280  11  6   1.0   0.5
  9750   9.6  49.3  235  12  6  -1.3  -0.7 |  11.5  52.7  275   9  5   0.9   0.5
  9500   9.4  48.9  225  12  6  -0.0  -0.0 |  11.5  52.7  270   8  4   1.2   0.7
  9250   9.5  49.1  220  12  6   0.5   0.3 |  11.5  52.7  255   6  3   1.2   0.7
  9000   9.5  49.1  215  11  6   2.3   1.3 |  11.6  52.9  240   5  3   2.2   1.2
  8750   9.8  49.6  210  11  6   4.7   2.6 |  11.7  53.1  205   4  2   3.3   1.8
  8500  10.1  50.2  205  11  6   4.2   2.3 |  11.9  53.4  180   5  2   5.6   3.0
  8250  10.4  50.7  205  11  6   4.0   2.2 |  12.5  54.5  175   4  2   7.0   3.8
  8000  10.7  51.3  200  11  6   4.5   2.5 |  13.0  55.4  175   4  2   7.4   4.0
  7750  11.1  52.0  195  12  6   4.9   2.7 |  13.6  56.5  170   4  2   9.3   5.1
  7500  11.5  52.7  190  12  6   3.6   2.0 |  14.3  57.7  170   4  2  10.0   5.5
  7250  11.8  53.2  180  12  6   3.9   2.2 |  15.0  59.0  170   4  2  10.2   5.6
  7000  12.0  53.6  170  12  6   0.9   0.5 |  15.8  60.4  170   4  2   9.9   5.5
  6750  12.1  53.8  160  13  7   4.7   2.6 |  16.6  61.9  165   4  2  10.1   5.6
  6500  12.9  55.2  155  12  6  11.0   6.0 |  17.3  63.1  165   3  2  10.6   5.8
  6250  13.6  56.5  150  11  6   9.0   4.9 |  18.1  64.6  165   3  2  10.4   5.7
  6000  14.3  57.7  145  10  5  10.6   5.8 |  18.9  66.0  165   3  2  10.7   5.9
  5750  15.2  59.4  145   9  5  14.6   8.0 |  19.9  67.8  165   3  1  17.1   9.4
  5500  16.5  61.7  140   8  4  18.0   9.9 |  21.5  70.7  160   3  1  26.6  14.6

           08/23/2015 at 1500 MDT          |       08/23/2015 at 1800 MDT
                                           |
K index... +9.6  LI... -1.4                | K index... +15.4  LI... -2.1
CAPE... +463.1  CIN... -130.2              | CAPE... +642.3  CIN... -94.9
                                           |
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 -64.3 -83.7  285  29 15   2.7   1.5 | -64.8 -84.6  285  28 14   2.6   1.4
 45000 -58.9 -74.0  290  37 19   5.6   3.1 | -59.1 -74.4  290  38 19   6.6   3.6
 40000 -50.4 -58.7  290  35 18   4.0   2.2 | -49.3 -56.7  295  43 22   4.1   2.3
 38000 -48.0 -54.4  280  32 16   4.0   2.2 | -46.8 -52.2  290  39 20   4.1   2.3
 36000 -45.6 -50.1  270  29 15   4.0   2.2 | -44.3 -47.7  285  36 18   4.2   2.3
 34000 -41.0 -41.8  270  28 14   8.2   4.5 | -40.3 -40.5  275  32 17   7.0   3.8
 32000 -36.1 -33.0  265  27 14   8.1   4.4 | -36.2 -33.2  270  30 15   6.7   3.7
 30000 -31.7 -25.1  265  25 13   7.1   3.9 | -31.2 -24.2  275  27 14   8.5   4.7
 29000 -29.1 -20.4  265  24 12   7.1   3.9 | -28.1 -18.6  280  25 13   8.6   4.7
 28000 -26.9 -16.4  270  23 12   8.1   4.5 | -25.7 -14.3  285  24 12   6.3   3.4
 27000 -24.5 -12.1  275  21 11   8.0   4.4 | -23.7 -10.7  285  22 11   6.5   3.6
 26000 -22.1  -7.8  280  20 10   8.0   4.4 | -21.7  -7.1  290  19 10   6.5   3.6
 25000 -19.7  -3.5  285  19 10   7.7   4.2 | -19.7  -3.5  290  17  9   7.2   3.9
 24000 -17.5   0.5  285  19 10   7.5   4.1 | -17.4   0.7  290  18  9   7.8   4.3
 23000 -15.2   4.6  285  19 10   7.5   4.1 | -15.1   4.8  295  18  9   7.9   4.3
 22000 -13.0   8.6  285  19 10   7.6   4.1 | -12.7   9.1  295  18  9   7.6   4.1
 21000 -10.8  12.6  285  19 10   7.6   4.2 | -10.5  13.1  295  20 10   7.4   4.0
 20000  -8.5  16.7  285  20 10   7.6   4.2 |  -8.4  16.9  295  22 11   7.4   4.0
 19500  -7.4  18.7  285  20 10   7.6   4.2 |  -7.3  18.9  295  23 12   7.4   4.0
 19000  -6.2  20.8  285  20 11   7.7   4.2 |  -6.2  20.8  295  24 12   7.2   3.9
 18500  -5.1  22.8  285  21 11   7.7   4.2 |  -5.1  22.8  300  24 12   7.2   4.0
 18000  -3.9  25.0  290  22 11   7.6   4.2 |  -4.0  24.8  300  25 13   7.1   3.9
 17500  -2.8  27.0  290  23 12   7.6   4.2 |  -3.0  26.6  300  25 13   7.0   3.8
 17000  -1.7  28.9  295  24 12   7.6   4.2 |  -2.0  28.4  300  25 13   7.0   3.9
 16500  -0.6  30.9  295  24 12   7.2   3.9 |  -0.9  30.4  300  25 13   7.5   4.1
 16000   0.5  32.9  295  24 13   7.2   3.9 |   0.2  32.4  300  25 13   7.4   4.1
 15500   2.1  35.8  295  25 13   7.6   4.1 |   1.9  35.4  300  24 12   8.7   4.8
 15000   3.2  37.8  295  25 13   7.5   4.1 |   3.2  37.8  300  23 12   8.7   4.8
 14500   4.3  39.7  295  25 13   8.0   4.4 |   4.4  39.9  300  22 11   8.8   4.8
 14000   5.5  41.9  295  25 13   8.0   4.4 |   5.7  42.3  300  21 11   8.8   4.8
 13500   6.6  43.9  295  24 12   8.7   4.8 |   7.0  44.6  300  20 10   9.0   4.9
 13000   7.8  46.0  290  21 11   8.8   4.9 |   8.3  46.9  300  18  9   9.0   5.0
 12500   9.0  48.2  290  19 10   8.4   4.6 |   9.6  49.3  300  17  9   8.1   4.4
 12000  10.2  50.4  290  16  8   8.1   4.4 |  10.7  51.3  295  14  7   7.5   4.1
 11500  11.4  52.5  290  14  7   6.6   3.6 |  11.7  53.1  295  12  6   5.3   2.9
 11000  12.1  53.8  290  12  6   5.2   2.9 |  12.0  53.6  290   8  4   3.2   1.7
 10500  12.7  54.9  290   9  5   2.6   1.4 |  12.4  54.3  275   3  2   1.7   1.0
 10250  12.8  55.0  285   9  4   0.7   0.4 |  12.5  54.5  265   3  2   4.0   2.2
 10000  12.9  55.2  280   6  3   2.9   1.6 |  12.8  55.0  240   2  1   7.7   4.2
  9750  13.0  55.4  265   3  1   2.3   1.2 |  13.2  55.8  195   2  1   7.0   3.8
  9500  13.1  55.6  170   2  1   3.5   1.9 |  13.6  56.5  160   2  1   7.0   3.8
  9250  13.3  55.9  150   2  1   4.9   2.7 |  14.1  57.4  155   2  1   7.3   4.0
  9000  13.7  56.7  135   2  1   7.0   3.8 |  14.7  58.5  150   2  1   9.8   5.4
  8750  14.2  57.6  125   2  1   8.6   4.7 |  15.5  59.9  145   3  1  11.0   6.0
  8500  14.8  58.6  120   2  1   8.9   4.9 |  16.2  61.2  145   3  1   9.9   5.5
  8250  15.5  59.9  115   2  1   9.4   5.1 |  16.9  62.4  145   3  1   9.4   5.2
  8000  16.2  61.2  115   2  1   9.7   5.3 |  17.7  63.9  145   2  1   9.8   5.4
  7750  16.9  62.4  110   2  1  10.3   5.7 |  18.4  65.1  140   2  1  10.0   5.5
  7500  17.7  63.9  110   2  1  10.0   5.5 |  19.1  66.4  140   2  1   9.9   5.5
  7250  18.4  65.1  110   2  1  10.0   5.5 |  19.9  67.8  140   2  1   9.9   5.4
  7000  19.2  66.6  105   2  1   9.8   5.4 |  20.6  69.1  140   2  1  10.0   5.5
  6750  19.9  67.8  105   2  1  10.3   5.6 |  21.4  70.5  140   2  1  10.0   5.5
  6500  20.7  69.3  105   2  1  10.9   6.0 |  22.1  71.8  135   2  1  10.1   5.5
  6250  21.5  70.7  100   2  1  11.0   6.0 |  22.9  73.2  135   2  1  10.0   5.5
  6000  22.3  72.1  095   2  1  10.4   5.7 |  23.6  74.5  135   2  1  10.4   5.7
  5750  23.2  73.8  090   2  1  16.1   8.8 |  24.5  76.1  135   2  1  13.5   7.4
  5500  24.8  76.6  090   2  1  26.9  14.8 |  25.6  78.1  135   2  1  17.2   9.4
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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