Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260116
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1916 MDT Friday, July 25, 2014

This forecast is for Saturday, July 26, 2014:

If the trigger temperature of 86.5 F/30.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1004 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16223 ft MSL (10936 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1045 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................. 10863 ft MSL (5576 ft AGL)
Thermal soaring outlook for Sunday 07/27....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 29605 ft MSL (24318 ft AGL)
Wave soaring outlook for Sunday 07/27.......... Poor

Remarks...

Sunrise/Sunset.................... 05:53:08 / 20:19:07 MDT
Total possible sunshine........... 14 hr 25 min 59 sec (865 min 59 sec)
Altitude of sun at 13:05:56 MDT... 69.53 degrees

Upper air data from numerical model forecast valid on 07/26/2014 at 0600 MDT

Freezing level.................. 16738 ft MSL (11451 ft AGL)
Convective condensation level... 17848 ft MSL (12561 ft AGL)
Lifted condensation level....... 17433 ft MSL (12145 ft AGL)
Lifted index.................... -0.7
K index......................... +18.9

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  -67.8 -90.0   270   24   13   1.6   0.9      M     M       M      M    M
 45000  -62.1 -79.8   270   38   20   7.7   4.2      M     M       M      M    M
 40000  -50.1 -58.2   265   49   25   7.6   4.2      M     M       M      M    M
 38000  -45.5 -49.9   265   49   25   7.6   4.2      M     M       M      M    M
 36000  -41.0 -41.8   265   48   25   7.1   3.9      M     M       M      M    M
 34000  -36.9 -34.4   265   41   21   6.9   3.8      M     M       M      M    M
 32000  -32.7 -26.9   270   34   18   7.5   4.1      M     M       M      M    M
 30000  -28.2 -18.8   270   33   17   7.8   4.3   48.1 118.6    10.8      M    M
 29000  -25.8 -14.4   270   33   17   7.8   4.3   47.4 117.3    10.3      M    M
 28000  -23.0  -9.4   270   32   16   7.4   4.1   46.4 115.6     9.7      M    M
 27000  -20.8  -5.4   275   30   16   7.5   4.1   45.5 113.9     9.0      M    M
 26000  -18.6  -1.5   275   29   15   7.5   4.1   44.7 112.4     8.4      M    M
 25000  -16.5   2.3   275   27   14   6.1   3.4   43.8 110.9     7.8      M    M
 24000  -14.8   5.4   275   25   13   5.7   3.1   42.3 108.1     6.6      M    M
 23000  -13.1   8.4   275   23   12   5.7   3.1   40.8 105.4     5.4      M    M
 22000  -11.3  11.7   275   22   11   6.7   3.7   39.5 103.1     4.4      M    M
 21000   -9.3  15.3   275   22   11   7.0   3.8   38.4 101.1     3.5      M    M
 20000   -7.2  19.0   280   21   11   7.0   3.8   37.5  99.4     2.8      M    M
 19500   -6.2  20.8   280   21   11   7.1   3.9   37.0  98.7     2.4      M    M
 19000   -5.1  22.8   280   20   11   7.5   4.1   36.6  97.9     2.0      M    M
 18500   -4.0  24.8   280   19   10   7.5   4.1   36.2  97.2     1.7      M    M
 18000   -2.9  26.8   280   18    9   7.3   4.0   35.8  96.5     1.3      M    M
 17500   -1.8  28.8   280   17    9   7.2   4.0   35.4  95.7     0.9      M    M
 17000   -0.8  30.6   275   15    8   7.4   4.1   35.0  94.9     0.5      M    M
 16500    0.4  32.7   275   14    7   8.2   4.5   34.7  94.4     0.2      M    M
 16000    1.6  34.9   280   13    7   8.2   4.5   34.4  93.9    -0.1    991  5.0
 15500    2.7  36.9   280   12    6   8.2   4.5   34.1  93.4    -0.3    940  4.8
 15000    3.9  39.0   285   11    6   8.2   4.5   33.9  93.0    -0.6    890  4.5
 14500    5.1  41.2   290   10    5   8.2   4.5   33.6  92.5    -0.9    839  4.3
 14000    6.9  44.4   300    8    4   8.3   4.5   33.2  91.8    -1.3    763  3.9
 13500    8.1  46.6   310    7    4   8.0   4.4   33.0  91.4    -1.5    713  3.6
 13000    9.3  48.7   325    6    3   8.0   4.4   32.7  90.9    -1.8    663  3.4
 12500   10.4  50.7   345    6    3   8.1   4.4   32.4  90.4    -2.1    614  3.1
 12000   11.6  52.9   005    6    3   8.1   4.5   32.2  89.9    -2.4    564  2.9
 11500   12.8  55.0   020    7    3   8.3   4.6   31.9  89.5    -2.7    514  2.6
 11000   14.0  57.2   030    7    4   8.3   4.6   31.7  89.1    -3.0    462  2.3
 10500   15.3  59.5   035    8    4   4.8   2.6   31.5  88.7    -3.2    410  2.1
 10250   15.5  59.9   035    8    4   7.2   4.0   31.0  87.8    -3.7    395  2.0
 10000   16.4  61.5   030    8    4  12.9   7.1   31.2  88.1    -3.6    362  1.8
  9750   17.2  63.0   030    8    4  12.0   6.6   31.3  88.4    -3.4    328  1.7
  9500   18.1  64.6   025    8    4   9.2   5.0   31.5  88.7    -3.3    296  1.5
  9250   18.6  65.5   020    8    4   7.4   4.0   31.3  88.3    -3.5    272  1.4
  9000   19.3  66.7   010    8    4  10.1   5.6   31.2  88.2    -3.6    244  1.2
  8750   20.1  68.2   005    8    4  10.4   5.7   31.3  88.3    -3.5    214  1.1
  8500   20.8  69.4   355    8    4   8.9   4.9   31.3  88.3    -3.5    185  0.9
  8250   21.4  70.5   355    7    4   8.0   4.4   31.2  88.1    -3.7    159  0.8
  8000   22.0  71.6   350    7    4   7.6   4.1   31.0  87.9    -3.8    134  0.7
  7750   22.5  72.5   350    6    3   6.9   3.8   30.8  87.5    -4.0    111  0.6
  7500   23.1  73.6   350    6    3   7.8   4.3   30.6  87.2    -4.2     88  0.4
  7250   23.6  74.5   340    6    3   7.8   4.3   30.5  86.9    -4.4     64  0.3
  7000   24.2  75.6   330    6    3   9.0   4.9   30.4  86.7    -4.6     39  0.2
  6750   24.8  76.6   325    7    3   4.5   2.4   30.2  86.4    -4.7     14  0.1
  6500   24.8  76.6   315    7    4  -1.6  -0.9   29.5  85.1    -5.5      7  0.0
  6250   24.5  76.1   300    8    4  -7.0  -3.8   28.5  83.4    -6.5      9  0.0
  6000   24.1  75.4   295    8    4   9.6   5.3   27.6  81.6    -7.6     11  0.1
  5750   25.0  77.0   295   12    6  -5.5  -3.0   27.7  81.9    -7.5      M    M
  5500   21.7  71.1   270    7    4 -77.8 -42.7   23.9  75.0   -11.5     71  0.4

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

           07/26/2014 at 0900 MDT          |       07/26/2014 at 1200 MDT
                                           |
K index... +22.5  LI... -0.5               | K index... +25.3  LI... -2.5
CAPE... +20.0  CIN... -181.0               | CAPE... +328.8  CIN... -54.2
                                           |
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 -67.5 -89.5  270  30 16   1.0   0.5 | -67.2 -89.0  275  34 17   0.3   0.2
 45000 -62.5 -80.5  270  46 24   7.8   4.3 | -62.9 -81.2  275  53 27   7.8   4.3
 40000 -50.3 -58.5  275  51 26   7.5   4.1 | -50.6 -59.1  280  53 27   7.7   4.2
 38000 -45.8 -50.4  275  50 26   7.5   4.1 | -46.0 -50.8  280  52 27   7.7   4.2
 36000 -41.3 -42.3  270  49 25   7.2   4.0 | -41.4 -42.5  280  51 26   7.4   4.1
 34000 -37.0 -34.6  270  42 22   7.1   3.9 | -37.1 -34.8  275  47 24   7.3   4.0
 32000 -32.8 -27.0  270  36 19   7.9   4.3 | -32.7 -26.9  275  44 23   8.1   4.5
 30000 -28.0 -18.4  275  33 17   8.0   4.4 | -28.3 -18.9  270  37 19   7.5   4.1
 29000 -25.6 -14.1  275  31 16   8.0   4.4 | -25.5 -13.9  270  32 17   7.5   4.1
 28000 -22.7  -8.9  275  29 15   7.5   4.1 | -23.3  -9.9  270  30 15   7.1   3.9
 27000 -20.5  -4.9  275  28 14   7.5   4.1 | -21.2  -6.2  270  29 15   7.2   3.9
 26000 -18.3  -0.9  280  27 14   7.6   4.1 | -19.1  -2.4  270  27 14   7.2   3.9
 25000 -16.2   2.8  280  26 13   5.5   3.0 | -17.0   1.4  275  26 13   6.5   3.6
 24000 -14.7   5.5  275  24 12   5.0   2.7 | -15.2   4.6  270  24 12   6.4   3.5
 23000 -13.2   8.2  270  22 11   5.0   2.7 | -13.3   8.1  265  22 11   6.4   3.5
 22000 -11.7  10.9  265  21 11   6.6   3.6 | -11.4  11.5  265  20 10   6.4   3.5
 21000  -9.7  14.5  275  20 10   6.9   3.8 |  -9.6  14.7  270  18  9   6.4   3.5
 20000  -7.6  18.3  280  20 10   6.9   3.8 |  -7.7  18.1  280  16  8   6.4   3.5
 19500  -6.6  20.1  280  20 10   7.0   3.9 |  -6.7  19.9  285  15  8   6.6   3.6
 19000  -5.6  21.9  285  20 10   7.3   4.0 |  -5.8  21.6  290  14  7   6.8   3.8
 18500  -4.5  23.9  290  21 11   7.3   4.0 |  -4.8  23.4  295  14  7   6.8   3.7
 18000  -3.4  25.9  295  21 11   7.8   4.3 |  -3.7  25.3  300  14  7   7.6   4.2
 17500  -2.2  28.0  295  20 10   7.9   4.3 |  -2.6  27.3  305  14  7   7.7   4.2
 17000  -1.1  30.0  300  20 10   7.8   4.3 |  -1.5  29.3  305  14  7   7.6   4.2
 16500  -0.0  32.0  300  18  9   7.4   4.0 |  -0.4  31.3  310  13  7   7.5   4.1
 16000   1.1  34.0  300  17  9   7.4   4.1 |   0.7  33.3  310  13  7   7.6   4.1
 15500   2.1  35.8  300  15  8   7.1   3.9 |   1.8  35.2  310  13  6   7.6   4.2
 15000   3.1  37.6  300  13  7   7.2   3.9 |   2.9  37.2  315  12  6   7.6   4.2
 14500   4.7  40.5  300  10  5   7.1   3.9 |   4.6  40.3  315  12  6   8.1   4.5
 14000   5.8  42.4  295   7  4   7.0   3.9 |   5.8  42.4  315  11  6   8.1   4.4
 13500   6.9  44.4  295   5  3   8.5   4.6 |   7.0  44.6  310  11  5   8.3   4.6
 13000   8.1  46.6  295   4  2   8.4   4.6 |   8.3  46.9  310  10  5   8.3   4.6
 12500   9.4  48.9  295   3  1   9.2   5.1 |   9.5  49.1  305   9  5   8.6   4.7
 12000  10.8  51.4  300   3  2   9.4   5.2 |  10.8  51.4  300   8  4   8.6   4.7
 11500  12.1  53.8  310   4  2   9.1   5.0 |  12.1  53.8  295   8  4   9.0   4.9
 11000  13.5  56.3  315   5  3   9.0   4.9 |  13.4  56.1  295   8  4   9.3   5.1
 10500  14.6  58.3  315   7  3   3.7   2.0 |  14.6  58.3  295   8  4   3.9   2.2
 10250  14.9  58.8  320   7  3   6.7   3.7 |  14.9  58.8  290   8  4   7.3   4.0
 10000  15.7  60.3  320   7  4  12.8   7.0 |  15.7  60.3  290   8  4  12.3   6.8
  9750  16.6  61.9  320   7  4  11.2   6.1 |  16.5  61.7  290   7  4  10.5   5.8
  9500  17.3  63.1  325   7  3   7.9   4.3 |  17.2  63.0  290   7  4   7.5   4.1
  9250  17.8  64.0  325   6  3   6.0   3.3 |  17.7  63.9  285   7  4   6.5   3.5
  9000  18.3  64.9  325   5  3   9.1   5.0 |  18.3  64.9  285   6  3   9.4   5.2
  8750  19.0  66.2  320   5  2   9.3   5.1 |  19.0  66.2  285   5  3   8.9   4.9
  8500  19.6  67.3  325   4  2   7.5   4.1 |  19.4  66.9  290   4  2   5.6   3.1
  8250  20.1  68.2  340   4  2   6.5   3.6 |  19.7  67.5  320   2  1   4.4   2.4
  8000  20.6  69.1  350   4  2   7.2   3.9 |  20.0  68.0  010   2  1   5.0   2.7
  7750  21.1  70.0  360   5  3   5.6   3.1 |  20.2  68.4  040   4  2   7.1   3.9
  7500  21.3  70.3  015   6  3   2.0   1.1 |  20.8  69.4  045   5  3   9.6   5.2
  7250  21.4  70.5  025   7  4   1.7   0.9 |  21.6  70.9  045   5  3   9.7   5.3
  7000  21.4  70.5  030   9  5  -0.2  -0.1 |  22.3  72.1  045   5  3  10.1   5.6
  6750  21.4  70.5  035  12  6   2.9   1.6 |  23.1  73.6  045   5  3  10.7   5.9
  6500  21.8  71.2  040  11  6   8.2   4.5 |  23.8  74.8  045   5  3  10.7   5.9
  6250  22.3  72.1  040   9  5   7.4   4.0 |  24.6  76.3  045   5  3  10.4   5.7
  6000  22.9  73.2  040   8  4   8.3   4.5 |  25.4  77.7  045   5  3  11.7   6.4
  5750  23.6  74.5  040   7  4  13.2   7.3 |  26.5  79.7  045   5  3  18.0   9.9
  5500  24.8  76.6  040   7  3  19.4  10.6 |  28.1  82.6  045   5  3  24.5  13.4

           07/26/2014 at 1500 MDT          |       07/26/2014 at 1800 MDT
                                           |
K index... +26.8  LI... -3.6               | K index... +24.8  LI... -3.4
CAPE... +387.1  CIN... -19.1               | CAPE... +309.5  CIN... -30.4
                                           |
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 -67.6 -89.7  270  32 17   0.9   0.5 | -67.2 -89.0  280  30 16   0.7   0.4
 45000 -62.2 -80.0  275  49 25   7.7   4.2 | -62.0 -79.6  275  45 23   7.7   4.2
 40000 -50.7 -59.3  280  49 25   7.9   4.3 | -50.5 -58.9  280  43 22   7.8   4.3
 38000 -46.0 -50.8  280  48 25   7.9   4.3 | -45.8 -50.4  280  43 22   7.8   4.3
 36000 -41.2 -42.2  280  47 24   7.8   4.3 | -41.1 -42.0  285  42 22   7.9   4.4
 34000 -36.6 -33.9  275  47 24   7.8   4.3 | -36.3 -33.3  280  43 22   8.0   4.4
 32000 -31.9 -25.4  275  48 25   8.6   4.7 | -31.6 -24.9  275  44 23   8.7   4.8
 30000 -26.9 -16.4  270  39 20   7.5   4.1 | -26.6 -15.9  275  40 21   7.3   4.0
 29000 -24.7 -12.5  270  36 18   7.5   4.1 | -24.5 -12.1  275  38 20   7.3   4.0
 28000 -22.6  -8.7  270  33 17   6.5   3.6 | -22.4  -8.3  275  36 19   6.7   3.7
 27000 -20.7  -5.3  270  31 16   6.5   3.6 | -20.4  -4.7  275  34 18   6.7   3.7
 26000 -18.8  -1.8  270  29 15   6.5   3.6 | -18.4  -1.1  275  32 17   6.7   3.7
 25000 -16.9   1.6  270  28 14   5.9   3.3 | -16.5   2.3  270  30 15   5.7   3.1
 24000 -15.2   4.6  270  25 13   5.9   3.2 | -14.9   5.2  270  26 14   5.6   3.1
 23000 -13.5   7.7  270  22 12   5.9   3.2 | -13.3   8.1  270  23 12   5.6   3.1
 22000 -11.7  10.9  270  20 10   6.0   3.3 | -11.6  11.1  270  20 10   5.8   3.2
 21000 -10.0  14.0  270  18 10   6.0   3.3 |  -9.9  14.2  270  18  9   5.8   3.2
 20000  -8.2  17.2  275  17  9   6.1   3.4 |  -8.2  17.2  275  17  9   5.9   3.2
 19500  -7.3  18.9  280  16  8   7.0   3.8 |  -7.4  18.7  275  16  8   6.5   3.6
 19000  -6.1  21.0  280  16  8   8.6   4.7 |  -6.3  20.7  280  15  8   7.7   4.2
 18500  -4.8  23.4  285  15  8   8.6   4.7 |  -5.1  22.8  285  15  8   7.7   4.2
 18000  -3.6  25.5  290  15  8   7.8   4.3 |  -4.0  24.8  290  15  8   8.2   4.5
 17500  -2.5  27.5  290  15  8   7.7   4.2 |  -2.8  27.0  295  15  8   8.2   4.5
 17000  -1.3  29.7  290  14  7   7.5   4.1 |  -1.5  29.3  300  15  8   8.1   4.4
 16500  -0.3  31.5  295  14  7   7.1   3.9 |  -0.4  31.3  300  16  8   7.8   4.3
 16000   0.7  33.3  295  14  7   7.0   3.9 |   0.8  33.4  300  16  8   7.7   4.2
 15500   1.8  35.2  295  14  7   7.9   4.3 |   2.0  35.6  305  16  8   8.3   4.5
 15000   3.5  38.3  295  15  8   7.8   4.3 |   3.8  38.8  305  17  9   8.2   4.5
 14500   4.6  40.3  295  14  7   7.8   4.3 |   5.0  41.0  305  17  9   8.1   4.4
 14000   5.8  42.4  295  14  7   7.8   4.3 |   6.1  43.0  305  17  9   8.1   4.4
 13500   6.9  44.4  295  13  7   8.3   4.5 |   7.3  45.1  300  17  9   8.1   4.4
 13000   8.1  46.6  300  12  6   8.2   4.5 |   8.4  47.1  300  16  8   8.1   4.4
 12500   9.3  48.7  300  11  6   9.3   5.1 |   9.6  49.3  300  15  8   8.7   4.8
 12000  10.7  51.3  300  11  6   9.4   5.2 |  10.9  51.6  300  14  7   8.7   4.8
 11500  12.1  53.8  300  11  5   9.4   5.1 |  12.2  54.0  300  13  7   9.2   5.1
 11000  13.5  56.3  305  10  5   9.6   5.3 |  13.6  56.5  305  12  6   9.6   5.3
 10500  14.6  58.3  305  10  5   4.1   2.3 |  14.7  58.5  305  11  6   4.2   2.3
 10250  15.0  59.0  305   9  5   7.5   4.1 |  15.1  59.2  305  11  5   8.4   4.6
 10000  15.7  60.3  310   8  4  12.0   6.6 |  16.0  60.8  310  10  5  13.3   7.3
  9750  16.5  61.7  320   7  3  10.3   5.6 |  16.9  62.4  310   9  5  11.0   6.0
  9500  17.1  62.8  330   6  3   7.2   4.0 |  17.5  63.5  315   9  4   7.0   3.8
  9250  17.5  63.5  340   5  3   7.1   3.9 |  17.9  64.2  320   8  4   6.2   3.4
  9000  18.2  64.8  345   5  3  10.4   5.7 |  18.4  65.1  325   7  4   9.1   5.0
  8750  18.9  66.0  355   5  2  10.6   5.8 |  19.0  66.2  335   6  3   9.7   5.3
  8500  19.6  67.3  360   5  2   9.6   5.2 |  19.7  67.5  340   6  3   9.9   5.4
  8250  20.3  68.5  360   5  3   9.0   5.0 |  20.4  68.7  340   5  3  10.0   5.5
  8000  21.0  69.8  360   5  3  10.1   5.6 |  21.2  70.2  345   5  3  10.1   5.5
  7750  21.8  71.2  360   5  3  10.5   5.8 |  21.9  71.4  345   5  3   9.9   5.4
  7500  22.5  72.5  360   5  3   9.6   5.3 |  22.6  72.7  345   5  3   9.6   5.3
  7250  23.3  73.9  360   5  3   9.6   5.3 |  23.4  74.1  345   5  3   9.6   5.3
  7000  24.0  75.2  360   5  3   9.8   5.4 |  24.1  75.4  345   5  3   9.6   5.3
  6750  24.7  76.5  360   5  3  10.3   5.6 |  24.8  76.6  345   5  3   9.8   5.4
  6500  25.5  77.9  360   5  3  10.4   5.7 |  25.5  77.9  345   5  3  10.0   5.5
  6250  26.3  79.3  360   5  3  10.2   5.6 |  26.3  79.3  345   5  3   9.9   5.4
  6000  27.0  80.6  360   5  3  11.1   6.1 |  27.0  80.6  345   5  3  10.2   5.6
  5750  27.9  82.2  355   5  3  13.5   7.4 |  27.8  82.0  345   5  3  11.6   6.3
  5500  29.0  84.2  355   5  3  15.1   8.3 |  28.7  83.7  345   5  2  13.0   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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