Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 180048
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1848 MDT Sunday, August 17, 2014

This forecast is for Monday, August 18, 2014:

If the trigger temperature of 84.6 F/29.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 971 ft/min (4.9 m/s)
   Maximum height of thermals.................. 15693 ft MSL (10406 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8176 ft MSL (2888 ft AGL)
Thermal soaring outlook for Tuesday 08/19...... 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....................... 40716 ft MSL (35429 ft AGL)
Wave soaring outlook for Tuesday 08/19......... Poor

Remarks...

Sunrise/Sunset.................... 06:14:22 / 19:52:43 MDT
Total possible sunshine........... 13 hr 38 min 21 sec (818 min 21 sec)
Altitude of sun at 13:03:11 MDT... 63.16 degrees

Upper air data from numerical model forecast valid on 08/18/2014 at 0600 MDT

Freezing level.................. 15923 ft MSL (10636 ft AGL)
Convective condensation level... 18004 ft MSL (12717 ft AGL)
Lifted condensation level....... 17775 ft MSL (12487 ft AGL)
Lifted index.................... -0.9
K index......................... +17.7

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -62.9 -81.2   290   23   12   1.4   0.8      M     M       M      M    M
 45000  -59.7 -75.5   285   37   19   3.8   2.1      M     M       M      M    M
 40000  -53.8 -64.8   290   45   23   5.7   3.1      M     M       M      M    M
 38000  -50.3 -58.5   290   41   21   5.7   3.1      M     M       M      M    M
 36000  -46.9 -52.4   290   37   19   5.7   3.1      M     M       M      M    M
 34000  -42.6 -44.7   290   33   17   7.6   4.1      M     M       M      M    M
 32000  -38.0 -36.4   290   28   15   7.6   4.2      M     M       M      M    M
 30000  -32.6 -26.7   290   23   12   8.2   4.5   42.3 108.2     8.1      M    M
 29000  -30.2 -22.4   290   21   11   8.2   4.5   41.8 107.2     7.8      M    M
 28000  -27.7 -17.9   290   19   10   8.0   4.4   41.3 106.3     7.5      M    M
 27000  -25.4 -13.7   290   18    9   8.0   4.4   40.5 104.9     6.9      M    M
 26000  -23.0  -9.4   295   17    9   8.0   4.4   39.8 103.7     6.4      M    M
 25000  -20.6  -5.1   295   16    8   7.8   4.3   39.3 102.7     6.0      M    M
 24000  -18.6  -1.5   300   15    8   6.7   3.7   38.1 100.7     5.2      M    M
 23000  -16.6   2.1   305   14    7   6.7   3.7   37.0  98.6     4.3      M    M
 22000  -14.5   5.9   310   14    7   6.7   3.7   36.0  96.9     3.5      M    M
 21000  -12.5   9.5   315   14    7   6.8   3.7   34.9  94.8     2.6      M    M
 20000  -10.5  13.1   315   15    8   6.8   3.8   33.9  93.0     1.7      M    M
 19500   -9.5  14.9   315   15    8   6.6   3.6   33.4  92.1     1.3      M    M
 19000   -8.4  16.9   315   15    8   9.2   5.0   33.1  91.6     1.0      M    M
 18500   -7.1  19.2   305   15    8   9.0   4.9   33.0  91.3     0.8      M    M
 18000   -5.8  21.6   300   15    8   9.0   4.9   32.8  91.1     0.7      M    M
 17500   -4.5  23.9   300   14    7   9.0   4.9   32.7  90.8     0.5      M    M
 17000   -3.2  26.2   300   13    7   9.0   4.9   32.6  90.6     0.3      M    M
 16500   -1.9  28.6   300   13    6   9.1   5.0   32.4  90.4     0.2      M    M
 16000   -0.5  31.1   300   12    6   9.1   5.0   32.3  90.2     0.1      M    M
 15500    0.8  33.4   300   12    6   9.1   5.0   32.2  90.0    -0.0    963  4.9
 15000    2.8  37.0   300   11    6   9.2   5.0   32.1  89.7    -0.2    881  4.5
 14500    4.2  39.6   295   10    5   9.0   4.9   32.0  89.5    -0.3    826  4.2
 14000    5.5  41.9   295   10    5   9.0   4.9   31.8  89.3    -0.5    771  3.9
 13500    6.8  44.2   290    9    5   8.8   4.8   31.7  89.1    -0.6    716  3.6
 13000    8.2  46.8   290    9    5   8.8   4.8   31.5  88.8    -0.7    662  3.4
 12500    9.5  49.1   285    8    4   8.7   4.8   31.4  88.5    -0.9    608  3.1
 12000   10.7  51.3   280    8    4   8.6   4.7   31.2  88.2    -1.1    555  2.8
 11500   12.0  53.6   280    8    4   8.5   4.6   31.0  87.9    -1.3    502  2.6
 11000   13.3  55.9   275    7    4   8.0   4.4   30.8  87.4    -1.5    450  2.3
 10500   14.5  58.1   270    7    4   4.5   2.5   30.6  87.0    -1.7    398  2.0
 10250   14.7  58.5   270    7    4   5.5   3.0   30.0  86.0    -2.3    386  2.0
 10000   15.4  59.7   275    7    4  11.0   6.0   30.0  86.0    -2.3    356  1.8
  9750   16.2  61.2   275    7    4   9.9   5.4   30.0  86.1    -2.2    326  1.7
  9500   16.9  62.4   275    7    4   8.8   4.8   30.0  86.1    -2.2    296  1.5
  9250   17.5  63.5   280    7    4   7.1   3.9   29.9  85.8    -2.4    272  1.4
  9000   18.0  64.4   285    7    4   8.2   4.5   29.7  85.5    -2.6    248  1.3
  8750   18.7  65.7   295    7    4   8.9   4.9   29.6  85.3    -2.7    222  1.1
  8500   19.3  66.7   300    7    4   8.1   4.5   29.5  85.2    -2.8    195  1.0
  8250   19.9  67.8   310    8    4   7.6   4.2   29.4  84.9    -3.0    171  0.9
  8000   20.4  68.7   315    8    4   7.1   3.9   29.2  84.6    -3.1    147  0.7
  7750   20.9  69.6   320    9    4   7.0   3.8   29.0  84.2    -3.4    125  0.6
  7500   21.3  70.3   325    9    5   3.5   1.9   28.7  83.7    -3.7    105  0.5
  7250   21.4  70.5   330   10    5   0.6   0.3   28.0  82.5    -4.4     96  0.5
  7000   21.4  70.5   335   11    5   1.2   0.6   27.4  81.3    -5.1     87  0.4
  6750   21.4  70.5   335   11    6  -1.4  -0.8   26.7  80.0    -5.9     81  0.4
  6500   21.1  70.0   340   12    6  -3.4  -1.9   25.7  78.3    -6.9     81  0.4
  6250   20.7  69.3   335   11    6  -6.8  -3.7   24.6  76.3    -8.0     86  0.4
  6000   20.3  68.5   335   11    6   3.5   1.9   23.5  74.4    -9.2     91  0.5
  5750   20.7  69.3   335   12    6  -7.1  -3.9   23.2  73.7    -9.6     72  0.4
  5500   18.0  64.4   315    6    3 -56.2 -30.8   20.1  68.1   -13.0    145  0.7

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

           08/18/2014 at 0900 MDT          |       08/18/2014 at 1200 MDT
                                           |
K index... +19.8  LI... -1.8               | K index... +20.3  LI... -5.4
CAPE... +186.3  CIN... -394.8              | CAPE... +1369.0  CIN... -117.6
                                           |
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  295  22 11   1.3   0.7 | -62.3 -80.1  295  20 10   1.5   0.8
 45000 -59.6 -75.3  290  37 19   3.1   1.7 | -59.3 -74.7  290  36 18   2.8   1.5
 40000 -54.6 -66.3  285  44 23   6.2   3.4 | -54.7 -66.5  290  47 24   6.3   3.4
 38000 -50.9 -59.6  290  42 22   6.2   3.4 | -50.9 -59.6  295  45 23   6.2   3.4
 36000 -47.2 -53.0  295  40 21   6.1   3.4 | -47.2 -53.0  295  43 22   6.2   3.4
 34000 -42.9 -45.2  300  39 20   7.4   4.0 | -42.9 -45.2  295  41 21   7.4   4.1
 32000 -38.5 -37.3  300  38 19   7.4   4.1 | -38.4 -37.1  295  39 20   7.4   4.1
 30000 -32.8 -27.0  305  33 17   8.7   4.8 | -32.8 -27.0  295  33 17   8.6   4.7
 29000 -30.2 -22.4  305  31 16   8.7   4.8 | -30.2 -22.4  295  29 15   8.6   4.7
 28000 -27.6 -17.7  305  29 15   8.2   4.5 | -27.6 -17.7  290  26 13   8.2   4.5
 27000 -25.2 -13.4  305  25 13   8.1   4.4 | -25.2 -13.4  290  24 12   8.1   4.5
 26000 -22.8  -9.0  300  21 11   8.1   4.4 | -22.7  -8.9  290  22 11   8.1   4.5
 25000 -20.4  -4.7  295  17  9   7.7   4.2 | -20.3  -4.5  285  20 10   7.5   4.1
 24000 -18.5  -1.3  290  14  7   6.1   3.3 | -18.6  -1.5  280  18  9   5.3   2.9
 23000 -16.7   1.9  280  11  6   6.1   3.4 | -17.1   1.2  270  17  9   5.4   2.9
 22000 -15.0   5.0  265   9  5   6.3   3.5 | -15.5   4.1  260  16  8   6.1   3.4
 21000 -13.0   8.6  290  10  5   6.5   3.6 | -13.4   7.9  260  15  8   7.3   4.0
 20000 -11.1  12.0  315  12  6   6.5   3.6 | -11.3  11.7  265  14  7   7.4   4.1
 19500 -10.1  13.8  320  13  7   6.3   3.4 | -10.2  13.6  265  13  7   7.3   4.0
 19000  -8.9  16.0  320  14  7   9.9   5.4 |  -9.0  15.8  270  13  7   9.8   5.4
 18500  -7.5  18.5  315  13  7   9.6   5.3 |  -7.6  18.3  275  13  7   9.6   5.3
 18000  -6.1  21.0  305  12  6   9.5   5.2 |  -6.2  20.8  280  13  7   9.2   5.0
 17500  -4.7  23.5  305  12  6   9.5   5.2 |  -4.9  23.2  285  13  7   8.8   4.8
 17000  -3.4  25.9  300  12  6   9.6   5.2 |  -3.6  25.5  285  13  7   8.7   4.8
 16500  -2.1  28.2  300  12  6   8.6   4.7 |  -2.3  27.9  290  13  7   9.5   5.2
 16000  -0.8  30.6  305  12  6   8.7   4.8 |  -0.9  30.4  295  12  6   9.5   5.2
 15500   0.5  32.9  305  12  6   9.3   5.1 |   0.5  32.9  295  11  6   9.3   5.1
 15000   2.6  36.7  310  11  6   9.7   5.3 |   2.5  36.5  300  11  5   9.3   5.1
 14500   3.9  39.0  315  11  6   8.9   4.9 |   3.9  39.0  300  10  5   9.0   4.9
 14000   5.2  41.4  320  11  6   8.9   4.9 |   5.2  41.4  305   9  5   9.0   5.0
 13500   6.5  43.7  320  11  6   8.8   4.8 |   6.6  43.9  310   9  4   8.8   4.8
 13000   7.8  46.0  325  11  5   8.8   4.8 |   7.9  46.2  310   8  4   8.7   4.8
 12500   9.1  48.4  325  10  5   8.8   4.8 |   9.2  48.6  310   8  4   8.7   4.7
 12000  10.4  50.7  325  10  5   8.7   4.8 |  10.5  50.9  315   7  4   8.6   4.7
 11500  11.7  53.1  330  10  5   8.4   4.6 |  11.7  53.1  315   7  3   8.0   4.4
 11000  12.9  55.2  330  10  5   7.6   4.2 |  12.8  55.0  325   6  3   7.1   3.9
 10500  14.1  57.4  330   9  5   4.0   2.2 |  13.9  57.0  330   6  3   3.5   1.9
 10250  14.3  57.7  330   9  5   4.6   2.5 |  14.1  57.4  335   6  3   4.2   2.3
 10000  14.9  58.8  335   9  5   9.8   5.4 |  14.7  58.5  340   5  3   9.4   5.1
  9750  15.6  60.1  335   9  4   8.8   4.8 |  15.3  59.5  345   5  3   8.5   4.7
  9500  16.2  61.2  340   9  4   7.6   4.2 |  15.9  60.6  350   5  3   6.8   3.8
  9250  16.7  62.1  340   9  4   5.9   3.2 |  16.3  61.3  360   6  3   4.6   2.5
  9000  17.2  63.0  345   9  4   7.2   4.0 |  16.6  61.9  005   6  3   5.3   2.9
  8750  17.7  63.9  350   9  4   8.3   4.6 |  17.0  62.6  010   7  3   5.9   3.2
  8500  18.3  64.9  350   9  4   6.5   3.5 |  17.3  63.1  010   7  4   3.5   1.9
  8250  18.7  65.7  350   9  5   5.2   2.9 |  17.3  63.1  020   7  4   1.4   0.8
  8000  19.1  66.4  350  10  5   4.4   2.4 |  17.4  63.3  025   7  4   2.1   1.1
  7750  19.3  66.7  350  10  5   2.7   1.5 |  17.3  63.1  030   7  4   3.2   1.8
  7500  19.3  66.7  350  11  6  -1.4  -0.8 |  17.5  63.5  030   6  3   8.1   4.4
  7250  18.9  66.0  355  12  6  -3.9  -2.2 |  18.2  64.8  030   6  3  10.7   5.9
  7000  18.6  65.5  355  12  6  -3.9  -2.1 |  18.8  65.8  030   6  3  10.0   5.5
  6750  18.1  64.6  355  13  6  -2.7  -1.5 |  19.6  67.3  025   6  3  10.4   5.7
  6500  18.0  64.4  360  12  6   1.4   0.8 |  20.3  68.5  025   6  3  10.7   5.9
  6250  18.1  64.6  360  11  5   2.7   1.5 |  21.2  70.2  025   6  3  11.0   6.1
  6000  18.2  64.8  005   9  5   1.9   1.0 |  22.0  71.6  025   6  3  10.1   5.6
  5750  18.5  65.3  005   8  4   8.6   4.7 |  22.8  73.0  025   6  3  15.6   8.5
  5500  19.6  67.3  360   7  4  21.0  11.5 |  24.4  75.9  020   6  3  27.0  14.8

           08/18/2014 at 1500 MDT          |       08/18/2014 at 1800 MDT
                                           |
K index... +20.4  LI... -5.5               | K index... +24.5  LI... -3.7
CAPE... +1465.3  CIN... -34.9              | CAPE... +999.1  CIN... -18.3
                                           |
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 -61.5 -78.7  285  17  9   1.8   1.0 | -61.9 -79.4  295  19 10   1.9   1.0
 45000 -58.4 -73.1  285  32 16   2.2   1.2 | -58.8 -73.8  285  32 16   2.2   1.2
 40000 -54.6 -66.3  290  50 26   6.3   3.5 | -54.9 -66.8  285  48 25   6.3   3.4
 38000 -50.9 -59.6  290  49 25   6.2   3.4 | -51.1 -60.0  285  47 24   6.3   3.5
 36000 -47.1 -52.8  290  48 25   6.2   3.4 | -47.3 -53.1  280  46 24   6.2   3.4
 34000 -42.8 -45.0  290  46 24   7.5   4.1 | -42.4 -44.3  280  42 22   8.5   4.7
 32000 -37.7 -35.9  290  42 22   7.4   4.0 | -36.6 -33.9  280  36 19   9.0   5.0
 30000 -32.6 -26.7  290  37 19   8.6   4.7 | -31.6 -24.9  285  34 17   8.4   4.6
 29000 -30.0 -22.0  290  34 18   8.6   4.7 | -29.1 -20.4  285  33 17   8.4   4.6
 28000 -27.4 -17.3  290  32 16   8.2   4.5 | -26.6 -15.9  285  31 16   7.7   4.2
 27000 -25.0 -13.0  290  31 16   8.0   4.4 | -24.4 -11.9  285  30 16   7.6   4.2
 26000 -22.6  -8.7  290  29 15   8.0   4.4 | -22.1  -7.8  285  30 15   7.6   4.2
 25000 -20.2  -4.4  290  28 14   7.6   4.2 | -19.9  -3.8  285  29 15   7.6   4.2
 24000 -18.4  -1.1  285  27 14   5.8   3.2 | -17.7   0.1  285  28 14   7.3   4.0
 23000 -16.7   1.9  285  27 14   6.0   3.3 | -15.6   3.9  285  28 14   7.3   4.0
 22000 -15.0   5.0  280  27 14   6.6   3.6 | -13.4   7.9  285  27 14   7.1   3.9
 21000 -13.0   8.6  285  25 13   7.1   3.9 | -11.5  11.3  285  26 13   6.5   3.6
 20000 -10.9  12.4  290  23 12   7.1   3.9 |  -9.5  14.9  290  24 13   6.5   3.6
 19500  -9.8  14.4  295  23 12   6.9   3.8 |  -8.6  16.5  290  24 12   6.3   3.5
 19000  -8.6  16.5  295  22 11   9.4   5.2 |  -7.5  18.5  295  22 11   7.9   4.4
 18500  -7.2  19.0  295  21 11   9.2   5.0 |  -6.4  20.5  295  20 10   7.8   4.3
 18000  -5.9  21.4  300  20 10   9.2   5.1 |  -5.3  22.5  295  17  9   7.9   4.3
 17500  -4.5  23.9  300  18  9   9.4   5.1 |  -4.1  24.6  295  14  7   8.0   4.4
 17000  -3.2  26.2  300  17  9   9.4   5.2 |  -2.9  26.8  295  11  6   8.0   4.4
 16500  -1.8  28.8  300  15  8   8.7   4.8 |  -1.7  28.9  290   9  5   8.3   4.5
 16000  -0.5  31.1  305  14  7   8.8   4.8 |  -0.5  31.1  280   7  4   8.3   4.5
 15500   1.5  34.7  305  12  6   8.9   4.9 |   1.2  34.2  260   6  3   7.7   4.2
 15000   2.8  37.0  305  10  5   8.9   4.9 |   2.4  36.3  245   7  3   7.7   4.2
 14500   4.1  39.4  300   8  4   8.9   4.9 |   3.6  38.5  235   7  4   8.0   4.4
 14000   5.4  41.7  300   7  4   8.9   4.9 |   4.8  40.6  230   8  4   8.0   4.4
 13500   6.7  44.1  300   6  3   8.9   4.9 |   6.0  42.8  225   9  4   9.0   4.9
 13000   8.0  46.4  295   5  2   9.0   4.9 |   7.4  45.3  225   9  5   9.5   5.2
 12500   9.4  48.9  290   4  2   8.9   4.9 |   8.8  47.8  225   9  5   9.3   5.1
 12000  10.7  51.3  280   3  1   8.8   4.8 |  10.2  50.4  220   9  5   9.1   5.0
 11500  12.0  53.6  270   2  1   8.2   4.5 |  11.5  52.7  220   9  4   9.1   5.0
 11000  13.1  55.6  250   1  1   7.0   3.8 |  12.8  55.0  215   7  4   8.7   4.8
 10500  14.2  57.6  170   1  0   3.7   2.0 |  14.1  57.4  210   6  3   5.2   2.8
 10250  14.3  57.7  130   1  0   4.0   2.2 |  14.4  57.9  210   5  3   6.1   3.4
 10000  14.8  58.6  090   2  1   8.8   4.8 |  15.1  59.2  210   5  3  11.5   6.3
  9750  15.3  59.5  080   3  1   8.0   4.4 |  15.8  60.4  210   4  2  10.4   5.7
  9500  15.7  60.3  075   4  2   7.5   4.1 |  16.5  61.7  215   4  2   9.8   5.4
  9250  16.1  61.0  075   4  2   7.4   4.0 |  17.1  62.8  215   4  2   8.8   4.8
  9000  16.6  61.9  075   4  2   9.3   5.1 |  17.8  64.0  220   3  2   9.6   5.2
  8750  17.3  63.1  070   4  2   9.8   5.4 |  18.5  65.3  220   3  2   9.8   5.4
  8500  17.9  64.2  070   4  2   9.8   5.3 |  19.1  66.4  225   3  1   9.7   5.3
  8250  18.6  65.5  070   4  2   9.6   5.3 |  19.8  67.6  230   3  1   9.7   5.3
  8000  19.4  66.9  070   4  2  10.1   5.5 |  20.5  68.9  230   3  1   9.3   5.1
  7750  20.1  68.2  070   4  2  10.6   5.8 |  21.2  70.2  235   3  1   8.7   4.7
  7500  20.9  69.6  070   4  2  10.0   5.5 |  21.8  71.2  235   2  1   9.7   5.3
  7250  21.6  70.9  070   4  2   9.6   5.3 |  22.5  72.5  240   2  1  10.5   5.8
  7000  22.3  72.1  070   4  2   9.9   5.4 |  23.3  73.9  240   2  1  10.0   5.5
  6750  23.1  73.6  065   4  2  10.4   5.7 |  24.0  75.2  245   3  1   9.7   5.3
  6500  23.9  75.0  065   4  2  10.7   5.9 |  24.7  76.5  250   3  1  10.0   5.5
  6250  24.7  76.5  065   4  2  11.3   6.2 |  25.5  77.9  250   3  1  10.5   5.8
  6000  25.5  77.9  060   4  2   9.4   5.2 |  26.3  79.3  255   3  1   9.5   5.2
  5750  26.2  79.2  060   4  2  14.3   7.8 |  27.0  80.6  255   3  1  10.7   5.9
  5500  27.8  82.0  060   4  2  28.3  15.5 |  27.9  82.2  255   2  1  16.1   8.8
________________________________________________________________________________

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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