Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210136
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1936 MDT Sunday, July 20, 2014

This forecast is for Monday, July 21, 2014:

If the trigger temperature of 87.6 F/30.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1260 ft/min (6.4 m/s)
   Maximum height of thermals.................. 19570 ft MSL (14283 ft AGL)

Forecast maximum temperature................... 97.0 F/36.6 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14378 ft MSL (9090 ft AGL)
Thermal soaring outlook for Tuesday 07/22...... Excellent

Wave Soaring Index............................. Fair
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....................... 21496 ft MSL (16209 ft AGL)
Wave soaring outlook for Tuesday 07/22......... Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 05:48:52 / 20:23:07 MDT
Total possible sunshine........... 14 hr 34 min 15 sec (874 min 15 sec)
Altitude of sun at 13:05:52 MDT... 70.58 degrees

Upper air data from numerical model forecast valid on 07/21/2014 at 0600 MDT

Freezing level.................. 16647 ft MSL (11360 ft AGL)
Convective condensation level... 18275 ft MSL (12988 ft AGL)
Lifted condensation level....... 18757 ft MSL (13469 ft AGL)
Lifted index.................... -2.5
K index......................... +20.4

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  -65.9 -86.6   240   29   15   1.6   0.9      M     M       M      M    M
 45000  -61.4 -78.5   250   44   22   5.8   3.2      M     M       M      M    M
 40000  -51.9 -61.4   255   61   31   7.6   4.2      M     M       M      M    M
 38000  -47.3 -53.1   255   65   34   7.6   4.2      M     M       M      M    M
 36000  -42.8 -45.0   255   70   36   7.7   4.2      M     M       M      M    M
 34000  -38.1 -36.6   250   61   31   7.8   4.3      M     M       M      M    M
 32000  -33.5 -28.3   250   52   27   8.0   4.4      M     M       M      M    M
 30000  -29.5 -21.1   245   48   25   6.7   3.7   46.5 115.7     7.9      M    M
 29000  -27.5 -17.5   245   46   24   6.7   3.7   45.3 113.6     7.1      M    M
 28000  -25.0 -13.0   240   43   22   7.2   4.0   44.0 111.3     6.1      M    M
 27000  -22.8  -9.0   240   38   20   7.2   3.9   43.0 109.3     5.3      M    M
 26000  -20.7  -5.3   245   33   17   7.2   4.0   42.0 107.7     4.6      M    M
 25000  -18.6  -1.5   245   29   15   7.4   4.1   41.2 106.2     4.0      M    M
 24000  -16.3   2.7   245   27   14   7.5   4.1   40.3 104.5     3.2      M    M
 23000  -14.1   6.6   240   26   13   7.5   4.1   39.5 103.1     2.5      M    M
 22000  -11.9  10.6   235   24   12   7.3   4.0   38.8 101.8     1.9      M    M
 21000   -9.8  14.4   235   22   11   7.2   4.0   37.8 100.0     1.1      M    M
 20000   -7.7  18.1   240   20   10   7.2   4.0   36.9  98.5     0.3      M    M
 19500   -6.6  20.1   240   19   10   7.4   4.0   36.5  97.8    -0.0   1356  6.9
 19000   -5.5  22.1   240   18    9   7.7   4.2   36.2  97.1    -0.4   1308  6.6
 18500   -4.4  24.1   240   17    9   7.7   4.2   35.8  96.4    -0.7   1259  6.4
 18000   -3.2  26.2   245   16    8   7.5   4.1   35.4  95.8    -1.0   1211  6.1
 17500   -2.1  28.2   245   15    8   7.5   4.1   35.0  95.1    -1.4   1163  5.9
 17000   -1.0  30.2   245   14    7   7.7   4.2   34.7  94.4    -1.8   1115  5.7
 16500    0.2  32.4   245   13    7   8.3   4.5   34.4  93.9    -2.0   1065  5.4
 16000    1.4  34.5   250   12    6   8.2   4.5   34.1  93.5    -2.3   1014  5.2
 15500    2.6  36.7   250   12    6   8.8   4.9   33.9  93.1    -2.5    962  4.9
 15000    3.9  39.0   255   11    6   8.9   4.9   33.8  92.8    -2.7    909  4.6
 14500    5.2  41.4   255   10    5   8.8   4.8   33.6  92.5    -2.9    855  4.3
 14000    7.1  44.8   265    9    5   8.7   4.8   33.4  92.1    -3.2    776  3.9
 13500    8.4  47.1   275    9    5   9.0   4.9   33.2  91.8    -3.4    722  3.7
 13000    9.7  49.5   280    9    5   9.0   4.9   33.1  91.6    -3.5    668  3.4
 12500   11.0  51.8   285    9    5   8.8   4.8   33.0  91.4    -3.7    614  3.1
 12000   12.3  54.1   285   10    5   8.7   4.8   32.8  91.0    -3.9    561  2.9
 11500   13.6  56.5   290   10    5   8.8   4.9   32.6  90.8    -4.1    508  2.6
 11000   14.9  58.8   290   11    5   8.8   4.8   32.5  90.5    -4.3    454  2.3
 10500   16.1  61.0   295   11    5   4.7   2.6   32.3  90.2    -4.5    401  2.0
 10250   16.4  61.5   295   11    5   6.4   3.5   31.8  89.3    -5.0    387  2.0
 10000   17.2  63.0   295   11    6  11.6   6.4   31.9  89.4    -4.9    356  1.8
  9750   17.9  64.2   295   11    6  10.6   5.8   32.0  89.5    -4.9    325  1.7
  9500   18.7  65.7   295   11    6   8.5   4.7   32.0  89.6    -4.9    295  1.5
  9250   19.2  66.6   290   11    6   7.3   4.0   31.8  89.2    -5.1    272  1.4
  9000   19.8  67.6   290   11    6   9.4   5.1   31.7  89.1    -5.2    246  1.2
  8750   20.5  68.9   290   11    6   9.5   5.2   31.7  89.0    -5.2    217  1.1
  8500   21.2  70.2   290   11    6   8.7   4.8   31.7  89.0    -5.3    190  1.0
  8250   21.8  71.2   290   10    5   8.0   4.4   31.5  88.8    -5.4    164  0.8
  8000   22.4  72.3   290   10    5   8.7   4.8   31.4  88.6    -5.6    138  0.7
  7750   23.1  73.6   290    9    5   9.0   4.9   31.4  88.5    -5.6    111  0.6
  7500   23.8  74.8   290    9    5   8.5   4.6   31.3  88.3    -5.7     84  0.4
  7250   24.4  75.9   295   10    5   8.0   4.4   31.2  88.1    -5.9     59  0.3
  7000   25.0  77.0   295   11    6   8.9   4.9   31.1  87.9    -6.0     34  0.2
  6750   25.6  78.1   300   13    7   4.1   2.3   30.9  87.6    -6.1      8  0.0
  6500   25.6  78.1   300   12    6  -1.3  -0.7   30.2  86.3    -6.9      0  0.0
  6250   25.3  77.5   295   11    6  -6.9  -3.8   29.2  84.6    -7.9      2  0.0
  6000   25.0  77.0   290   10    5  10.8   5.9   28.3  82.9    -8.9      3  0.0
  5750   26.0  78.8   295    9    4  -6.6  -3.6   28.5  83.3    -8.7      M    M
  5500   22.2  72.0   265    5    3 -85.9 -47.2   24.3  75.7   -13.2     71  0.4

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

           07/21/2014 at 0900 MDT          |       07/21/2014 at 1200 MDT
                                           |
K index... +17.1  LI... 0.0                | K index... +15.4  LI... -0.5
CAPE... +47.2  CIN... -130.4               | CAPE... +108.4  CIN... -46.7
                                           |
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 -65.3 -85.5  240  32 16   0.7   0.4 | -65.1 -85.2  245  30 15   0.4   0.2
 45000 -61.8 -79.2  250  45 23   5.8   3.2 | -61.7 -79.1  255  44 23   6.1   3.3
 40000 -52.2 -62.0  255  58 30   7.4   4.1 | -51.8 -61.2  255  63 32   7.4   4.1
 38000 -47.8 -54.0  250  60 31   7.4   4.1 | -47.4 -53.3  250  63 32   7.4   4.1
 36000 -43.3 -45.9  245  63 32   7.9   4.3 | -43.0 -45.4  245  63 32   7.5   4.1
 34000 -38.3 -36.9  250  59 30   8.4   4.6 | -38.4 -37.1  245  57 29   7.7   4.2
 32000 -33.3 -27.9  250  55 28   8.7   4.8 | -33.8 -28.8  245  51 26   8.2   4.5
 30000 -29.4 -20.9  245  49 25   6.3   3.5 | -29.8 -21.6  245  45 23   6.5   3.6
 29000 -27.6 -17.7  245  47 24   6.3   3.5 | -27.3 -17.1  245  41 21   6.5   3.6
 28000 -25.2 -13.4  240  43 22   6.9   3.8 | -25.4 -13.7  245  39 20   6.5   3.6
 27000 -23.1  -9.6  240  39 20   6.9   3.8 | -23.4 -10.1  240  37 19   6.5   3.6
 26000 -21.1  -6.0  240  35 18   6.9   3.8 | -21.5  -6.7  240  35 18   6.5   3.6
 25000 -19.0  -2.2  240  31 16   7.2   3.9 | -19.5  -3.1  240  32 17   7.1   3.9
 24000 -16.9   1.6  240  29 15   7.3   4.0 | -17.4   0.7  240  29 15   7.3   4.0
 23000 -14.7   5.5  240  26 13   7.4   4.1 | -15.3   4.5  240  26 14   7.4   4.1
 22000 -12.6   9.3  235  24 12   7.6   4.2 | -13.1   8.4  245  24 12   7.9   4.3
 21000 -10.3  13.5  240  23 12   7.6   4.2 | -10.7  12.7  245  22 11   7.9   4.3
 20000  -8.0  17.6  245  22 11   7.6   4.2 |  -8.4  16.9  245  20 10   7.9   4.3
 19500  -6.9  19.6  245  21 11   7.6   4.2 |  -7.2  19.0  245  19 10   8.0   4.4
 19000  -5.8  21.6  250  20 10   7.5   4.1 |  -6.0  21.2  245  17  9   8.2   4.5
 18500  -4.7  23.5  250  18  9   7.5   4.1 |  -4.8  23.4  245  16  8   8.2   4.5
 18000  -3.6  25.5  255  16  8   7.5   4.1 |  -3.6  25.5  250  14  7   8.1   4.4
 17500  -2.5  27.5  255  14  7   7.6   4.2 |  -2.3  27.9  250  13  7   8.1   4.5
 17000  -1.4  29.5  260  12  6   7.8   4.3 |  -1.1  30.0  250  13  6   8.3   4.6
 16500  -0.1  31.8  265  11  6   8.4   4.6 |   0.1  32.2  255  12  6   8.6   4.7
 16000   1.1  34.0  270  10  5   8.4   4.6 |   1.4  34.5  255  12  6   8.6   4.7
 15500   2.4  36.3  275  10  5   8.9   4.9 |   2.7  36.9  260  12  6   9.0   4.9
 15000   3.7  38.7  280  10  5   8.9   4.9 |   4.1  39.4  265  13  7   8.9   4.9
 14500   5.7  42.3  290  11  6   9.2   5.1 |   6.0  42.8  275  14  7   8.8   4.8
 14000   7.1  44.8  290  12  6   9.3   5.1 |   7.3  45.1  275  15  8   8.8   4.9
 13500   8.4  47.1  295  13  7   8.7   4.8 |   8.6  47.5  280  15  8   8.9   4.9
 13000   9.7  49.5  295  15  8   8.7   4.8 |   9.9  49.8  285  16  8   8.9   4.9
 12500  11.0  51.8  295  16  8   8.9   4.9 |  11.2  52.2  290  16  8   8.3   4.5
 12000  12.3  54.1  295  17  9   9.0   4.9 |  12.3  54.1  295  16  8   8.3   4.5
 11500  13.6  56.5  295  18  9   8.8   4.8 |  13.5  56.3  300  15  8   8.4   4.6
 11000  14.9  58.8  295  18  9   8.8   4.8 |  14.7  58.5  305  14  7   8.7   4.8
 10500  16.0  60.8  295  19 10   5.1   2.8 |  15.7  60.3  310  13  7   4.0   2.2
 10250  16.4  61.5  295  19 10   8.1   4.5 |  16.1  61.0  310  12  6   8.1   4.4
 10000  17.2  63.0  295  19 10  12.1   6.6 |  16.8  62.2  310  11  6  12.0   6.6
  9750  18.0  64.4  295  18  9  11.1   6.1 |  17.6  63.7  315  10  5  10.8   5.9
  9500  18.8  65.8  295  18  9   8.0   4.4 |  18.3  64.9  315   9  5   8.3   4.6
  9250  19.2  66.6  295  18  9   7.0   3.8 |  18.9  66.0  315   9  5   8.6   4.7
  9000  19.9  67.8  295  17  9   9.6   5.3 |  19.7  67.5  315   9  4  11.6   6.4
  8750  20.6  69.1  295  16  8   9.7   5.3 |  20.5  68.9  315   8  4  11.4   6.2
  8500  21.3  70.3  295  15  8   9.4   5.1 |  21.3  70.3  315   8  4  10.1   5.5
  8250  21.9  71.4  295  14  7   9.2   5.0 |  22.1  71.8  310   8  4   9.5   5.2
  8000  22.6  72.7  295  13  7   9.4   5.1 |  22.8  73.0  310   8  4   9.9   5.4
  7750  23.3  73.9  295  13  6   9.1   5.0 |  23.6  74.5  310   8  4  10.1   5.6
  7500  24.0  75.2  295  13  7   8.4   4.6 |  24.3  75.7  310   8  4  10.3   5.6
  7250  24.6  76.3  295  13  7   8.2   4.5 |  25.1  77.2  310   8  4  10.4   5.7
  7000  25.2  77.4  300  14  7   8.0   4.4 |  25.8  78.4  310   8  4  10.2   5.6
  6750  25.6  78.1  300  15  8   5.8   3.2 |  26.6  79.9  310   8  4  10.2   5.6
  6500  25.9  78.6  300  14  7   3.8   2.1 |  27.3  81.1  310   8  4  10.5   5.8
  6250  26.2  79.2  300  12  6   4.9   2.7 |  28.1  82.6  310   8  4  10.0   5.5
  6000  26.4  79.5  295  10  5   1.7   0.9 |  28.9  84.0  310   8  4  11.7   6.4
  5750  26.5  79.7  285   8  4   4.5   2.5 |  29.9  85.8  310   7  4  17.4   9.5
  5500  27.2  81.0  280   6  3  18.6  10.2 |  31.4  88.5  310   7  4  21.7  11.9

           07/21/2014 at 1500 MDT          |       07/21/2014 at 1800 MDT
                                           |
K index... +23.1  LI... -1.1               | K index... +24.1  LI... -0.7
CAPE... +124.8  CIN... -19.0               | CAPE... +80.0  CIN... -23.4
                                           |
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 -65.7 -86.3  240  29 15   1.2   0.6 | -65.9 -86.6  240  31 16   1.2   0.7
 45000 -60.9 -77.6  250  46 24   6.3   3.4 | -61.0 -77.8  255  47 24   6.3   3.5
 40000 -51.3 -60.3  255  63 33   7.2   4.0 | -51.2 -60.2  260  60 31   7.5   4.1
 38000 -46.9 -52.4  255  63 32   7.2   4.0 | -46.7 -52.1  255  60 31   7.5   4.1
 36000 -42.6 -44.7  250  63 33   7.5   4.1 | -42.2 -44.0  255  61 31   7.5   4.1
 34000 -37.9 -36.2  245  60 31   7.7   4.2 | -37.7 -35.9  250  55 28   7.5   4.1
 32000 -33.3 -27.9  245  57 29   8.3   4.6 | -33.2 -27.8  245  49 25   8.2   4.5
 30000 -28.8 -19.8  245  47 24   6.6   3.6 | -28.6 -19.5  245  40 21   6.9   3.8
 29000 -26.9 -16.4  245  43 22   6.6   3.6 | -26.5 -15.7  250  37 19   6.9   3.8
 28000 -24.9 -12.8  245  38 20   6.5   3.6 | -24.5 -12.1  255  33 17   6.7   3.7
 27000 -23.0  -9.4  250  34 17   6.6   3.6 | -22.5  -8.5  255  28 14   6.7   3.7
 26000 -21.0  -5.8  250  30 15   6.6   3.6 | -20.5  -4.9  260  23 12   6.7   3.7
 25000 -19.1  -2.4  255  26 13   7.1   3.9 | -18.5  -1.3  260  19 10   6.8   3.7
 24000 -16.9   1.6  255  24 12   7.2   4.0 | -16.5   2.3  265  18  9   6.9   3.8
 23000 -14.8   5.4  255  22 12   7.3   4.0 | -14.5   5.9  265  17  9   6.9   3.8
 22000 -12.7   9.1  260  21 11   7.1   3.9 | -12.5   9.5  270  15  8   7.3   4.0
 21000 -10.6  12.9  265  19 10   7.2   3.9 | -10.3  13.5  275  14  7   7.3   4.0
 20000  -8.5  16.7  270  17  9   7.2   4.0 |  -8.2  17.2  280  13  7   7.3   4.0
 19500  -7.4  18.7  275  16  8   7.7   4.2 |  -7.1  19.2  280  12  6   7.5   4.1
 19000  -6.2  20.8  275  15  8   8.4   4.6 |  -6.0  21.2  285  12  6   7.9   4.3
 18500  -5.0  23.0  280  14  7   8.4   4.6 |  -4.8  23.4  285  11  6   7.9   4.3
 18000  -3.8  25.2  285  14  7   8.4   4.6 |  -3.6  25.5  285  10  5   8.2   4.5
 17500  -2.5  27.5  285  14  7   8.4   4.6 |  -2.4  27.7  285   9  5   8.2   4.5
 17000  -1.3  29.7  285  13  7   8.5   4.7 |  -1.2  29.8  280   8  4   8.3   4.5
 16500  -0.0  32.0  285  13  7   8.7   4.8 |   0.0  32.0  275   7  4   8.4   4.6
 16000   1.3  34.3  285  12  6   8.6   4.7 |   1.3  34.3  270   6  3   8.3   4.6
 15500   2.6  36.7  280  11  6   9.3   5.1 |   3.3  37.9  260   6  3   9.4   5.1
 15000   4.6  40.3  275  10  5   9.3   5.1 |   4.6  40.3  250   6  3   9.4   5.2
 14500   6.0  42.8  270  10  5   9.3   5.1 |   6.0  42.8  250   6  3   9.5   5.2
 14000   7.4  45.3  270   9  5   9.3   5.1 |   7.4  45.3  245   7  3   9.5   5.2
 13500   8.7  47.7  265   8  4   9.3   5.1 |   8.9  48.0  245   7  3   9.4   5.1
 13000  10.1  50.2  270   8  4   9.3   5.1 |  10.2  50.4  240   7  4   9.4   5.1
 12500  11.5  52.7  270   7  4   9.2   5.1 |  11.6  52.9  240   7  4   9.4   5.1
 12000  12.9  55.2  270   7  3   9.2   5.1 |  13.0  55.4  240   8  4   9.3   5.1
 11500  14.3  57.7  270   6  3   9.4   5.1 |  14.4  57.9  240   8  4   9.7   5.3
 11000  15.6  60.1  270   5  3   9.7   5.3 |  15.9  60.6  235   8  4  10.1   5.6
 10500  16.7  62.1  270   4  2   4.7   2.6 |  17.1  62.8  235   8  4   5.0   2.8
 10250  17.2  63.0  270   4  2   8.6   4.7 |  17.5  63.5  235   8  4   9.5   5.2
 10000  18.0  64.4  275   4  2  12.0   6.6 |  18.4  65.1  235   8  4  13.1   7.2
  9750  18.8  65.8  275   3  2  10.9   6.0 |  19.4  66.9  235   8  4  11.7   6.4
  9500  19.5  67.1  275   3  2   8.8   4.8 |  20.1  68.2  235   8  4   8.0   4.4
  9250  20.2  68.4  275   3  2   9.1   5.0 |  20.6  69.1  235   8  4   7.8   4.3
  9000  20.9  69.6  275   3  2  11.5   6.3 |  21.4  70.5  240   8  4  11.0   6.1
  8750  21.8  71.2  280   3  2  11.1   6.1 |  22.2  72.0  240   8  4  10.8   5.9
  8500  22.6  72.7  280   3  2   9.7   5.3 |  23.0  73.4  240   8  4  10.3   5.6
  8250  23.3  73.9  280   3  2   9.1   5.0 |  23.7  74.7  240   8  4  10.1   5.5
  8000  24.0  75.2  280   4  2   9.9   5.4 |  24.4  75.9  240   8  4   9.8   5.4
  7750  24.7  76.5  280   4  2  10.4   5.7 |  25.1  77.2  245   8  4   9.7   5.3
  7500  25.5  77.9  280   4  2  10.3   5.6 |  25.9  78.6  245   8  4  10.1   5.5
  7250  26.3  79.3  280   4  2  10.6   5.8 |  26.6  79.9  245   8  4  10.3   5.6
  7000  27.0  80.6  280   4  2   9.6   5.3 |  27.4  81.3  245   8  4   9.9   5.4
  6750  27.7  81.9  280   4  2  10.1   5.5 |  28.1  82.6  245   8  4  10.0   5.5
  6500  28.6  83.5  280   4  2  11.4   6.3 |  28.9  84.0  245   8  4  10.4   5.7
  6250  29.4  84.9  280   4  2  11.6   6.4 |  29.7  85.5  245   8  4  10.7   5.9
  6000  30.2  86.4  280   4  2  10.3   5.6 |  30.5  86.9  245   8  4   9.5   5.2
  5750  31.1  88.0  280   4  2  15.3   8.4 |  31.2  88.2  245   8  4  10.8   5.9
  5500  32.7  90.9  285   4  2  27.7  15.2 |  32.2  90.0  250   7  4  16.4   9.0
________________________________________________________________________________

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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