Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 060045
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1845 MDT Sunday, July 5, 2015

This forecast is for Monday, July 6, 2015:

If the trigger temperature of 72.1 F/22.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7985 ft MSL (2678 ft AGL)

Forecast maximum temperature................... 70.0 F/21.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 5468 ft MSL (161 ft AGL)
Thermal soaring outlook for Tuesday 07/07...... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15380 ft MSL (10073 ft AGL)
Wave soaring outlook for Tuesday 07/07......... Poor

Remarks...

Sunrise/Sunset.................... 05:37:52 / 20:30:37 MDT
Total possible sunshine........... 14 hr 52 min 45 sec (892 min 45 sec)
Altitude of sun at 13:04:14 MDT... 72.86 degrees

Upper air data from numerical model forecast valid on 07/06/2015 at 0600 MDT

Freezing level.................. 16463 ft MSL (11156 ft AGL)
Convective condensation level... 10492 ft MSL (5185 ft AGL)
Lifted condensation level....... 9269 ft MSL (3962 ft AGL)
Lifted index.................... +2.8
K index......................... +17.2

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  -66.1 -87.0   240   26   13   1.2   0.7      M     M       M      M    M
 45000  -61.9 -79.4   245   40   20   6.2   3.4      M     M       M      M    M
 40000  -51.7 -61.1   240   55   29   7.9   4.4      M     M       M      M    M
 38000  -47.0 -52.6   240   48   25   7.9   4.3      M     M       M      M    M
 36000  -42.2 -44.0   240   42   21   8.4   4.6      M     M       M      M    M
 34000  -36.7 -34.1   245   41   21   9.3   5.1      M     M       M      M    M
 32000  -31.1 -24.0   250   41   21   9.3   5.1      M     M       M      M    M
 30000  -26.3 -15.3   255   35   18   7.7   4.2   50.9 123.7    22.6      M    M
 29000  -23.5 -10.3   255   31   16   7.7   4.2   50.0 122.0    22.2      M    M
 28000  -21.2  -6.2   260   28   14   7.7   4.2   49.3 120.7    21.9      M    M
 27000  -18.9  -2.0   255   26   13   7.7   4.2   48.4 119.1    21.5      M    M
 26000  -16.5   2.3   255   24   12   7.7   4.2   47.7 117.8    21.2      M    M
 25000  -14.2   6.4   250   22   11   7.2   3.9   47.0 116.7    20.9      M    M
 24000  -12.4   9.7   255   20   10   5.8   3.2   45.5 114.0    19.9      M    M
 23000  -10.7  12.7   255   18    9   5.9   3.2   44.1 111.4    18.9      M    M
 22000   -9.0  15.8   260   17    9   5.9   3.2   42.8 109.1    18.0      M    M
 21000   -7.4  18.7   265   16    8   5.7   3.1   41.3 106.4    16.8      M    M
 20000   -5.7  21.7   275   16    8   5.7   3.2   39.9 103.9    15.8      M    M
 19500   -4.9  23.2   275   16    8   5.8   3.2   39.3 102.7    15.3      M    M
 19000   -4.0  24.8   280   16    8   5.6   3.1   38.6 101.5    14.8      M    M
 18500   -3.2  26.2   290   16    8   5.6   3.1   37.9 100.2    14.2      M    M
 18000   -2.3  27.9   295   17    9   5.4   3.0   37.2  98.9    13.7      M    M
 17500   -1.6  29.1   300   18    9   4.5   2.5   36.3  97.4    13.0      M    M
 17000   -0.9  30.4   305   19   10   4.5   2.5   35.4  95.8    12.3      M    M
 16500   -0.2  31.6   310   20   10   5.0   2.8   34.6  94.3    11.6      M    M
 16000    0.5  32.9   315   20   10   5.1   2.8   33.8  92.9    10.9      M    M
 15500    1.5  34.7   320   21   11   4.6   2.5   32.6  90.7     9.9      M    M
 15000    2.1  35.8   320   22   11   4.7   2.6   31.8  89.2     9.0      M    M
 14500    2.7  36.9   325   22   11   5.3   2.9   31.0  87.7     8.2      M    M
 14000    3.5  38.3   325   22   11   5.7   3.1   30.3  86.5     7.6      M    M
 13500    4.2  39.6   325   22   11   5.7   3.1   29.6  85.3     6.9      M    M
 13000    5.0  41.0   325   22   11   5.7   3.1   28.9  84.1     6.3      M    M
 12500    5.8  42.4   330   22   11   5.6   3.1   28.3  82.9     5.6      M    M
 12000    6.5  43.7   330   22   11   5.3   2.9   27.6  81.7     4.9      M    M
 11500    7.3  45.1   330   21   11   5.3   2.9   26.9  80.4     4.2      M    M
 11000    8.0  46.4   330   20   10   5.5   3.0   26.2  79.2     3.5      M    M
 10500    8.7  47.7   330   19   10   4.1   2.3   25.5  78.0     2.8      M    M
 10250    8.9  48.0   330   19   10   3.7   2.0   25.0  77.1     2.3      M    M
 10000    9.3  48.7   330   18    9   6.4   3.5   24.7  76.4     1.9      M    M
  9750    9.7  49.5   335   18    9   6.9   3.8   24.4  76.0     1.6      M    M
  9500   10.2  50.4   335   17    9   6.6   3.6   24.2  75.6     1.4      M    M
  9250   10.6  51.1   335   17    9   5.9   3.3   23.9  75.1     1.1      M    M
  9000   11.0  51.8   340   17    9   6.8   3.7   23.7  74.6     0.7      M    M
  8750   11.5  52.7   345   16    8   7.8   4.3   23.5  74.3     0.5      M    M
  8500   12.0  53.6   345   16    8   7.6   4.2   23.3  74.0     0.3      M    M
  8250   12.6  54.7   350   16    8   7.9   4.3   23.2  73.7     0.2      M    M
  8000   13.2  55.8   355   17    9   7.8   4.3   23.0  73.4     0.0      M    M
  7750   13.7  56.7   355   17    9   7.5   4.1   22.9  73.1    -0.2    135  0.7
  7500   14.3  57.7   360   18    9   7.6   4.2   22.7  72.8    -0.3    112  0.6
  7250   14.8  58.6   360   18    9   7.8   4.3   22.5  72.6    -0.5     88  0.4
  7000   15.4  59.7   360   18    9   7.9   4.3   22.4  72.3    -0.7     64  0.3
  6750   16.0  60.8   005   18    9   8.4   4.6   22.3  72.1    -0.8     39  0.2
  6500   16.5  61.7   005   18    9   7.3   4.0   22.1  71.8    -1.0     14  0.1
  6250   17.0  62.6   360   16    8   5.9   3.2   21.9  71.4    -1.2      M    M
  6000   17.5  63.5   360   15    8   7.8   4.3   21.6  70.9    -1.5      M    M
  5750   18.1  64.6   360   14    7   4.9   2.7   21.5  70.7    -1.6      M    M
  5500   17.9  64.2   350    9    5  -6.2  -3.4   20.7  69.3    -2.5      M    M

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

           07/06/2015 at 0900 MDT          |       07/06/2015 at 1200 MDT
                                           |
K index... +27.2  LI... -0.7               | K index... +26.3  LI... -2.6
CAPE... +130.6  CIN... -29.7               | CAPE... +692.9  CIN... M
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.8 -86.4  235  28 14   1.5   0.8 | -64.7 -84.5  240  29 15   1.3   0.7
 45000 -61.5 -78.7  235  39 20   5.7   3.2 | -60.9 -77.6  230  42 22   5.1   2.8
 40000 -51.9 -61.4  240  55 28   8.0   4.4 | -52.1 -61.8  230  56 29   8.4   4.6
 38000 -47.1 -52.8  240  51 26   8.0   4.4 | -47.1 -52.8  230  52 27   8.4   4.6
 36000 -42.3 -44.1  240  47 24   8.3   4.6 | -42.0 -43.6  230  47 24   8.5   4.7
 34000 -37.0 -34.6  240  42 21   8.8   4.8 | -36.9 -34.4  235  41 21   8.6   4.7
 32000 -31.8 -25.2  245  36 18   8.8   4.8 | -31.7 -25.1  240  34 18   8.6   4.7
 30000 -27.1 -16.8  250  30 16   7.7   4.2 | -26.5 -15.7  245  27 14   7.5   4.1
 29000 -24.2 -11.6  255  27 14   7.7   4.2 | -24.3 -11.7  250  24 12   7.6   4.1
 28000 -21.9  -7.4  260  25 13   7.3   4.0 | -22.1  -7.8  255  22 11   6.7   3.7
 27000 -19.7  -3.5  255  24 12   7.4   4.0 | -20.0  -4.0  255  21 11   6.8   3.7
 26000 -17.5   0.5  250  23 12   7.4   4.0 | -18.0  -0.4  255  21 11   6.8   3.7
 25000 -15.3   4.5  245  22 11   7.1   3.9 | -16.0   3.2  255  20 10   6.6   3.6
 24000 -13.3   8.1  250  21 11   6.6   3.6 | -14.1   6.6  260  18  9   6.3   3.5
 23000 -11.4  11.5  255  19 10   6.6   3.6 | -12.3   9.9  265  17  9   6.4   3.5
 22000  -9.4  15.1  260  18  9   6.1   3.3 | -10.4  13.3  270  15  8   6.3   3.5
 21000  -7.9  17.8  265  17  9   5.1   2.8 |  -8.7  16.3  275  13  7   6.1   3.4
 20000  -6.4  20.5  275  15  8   5.3   2.9 |  -7.0  19.4  285  12  6   6.2   3.4
 19500  -5.7  21.7  280  15  8   5.3   2.9 |  -6.1  21.0  290  12  6   6.4   3.5
 19000  -4.8  23.4  285  14  7   6.3   3.5 |  -5.3  22.5  295  11  6   5.1   2.8
 18500  -3.9  25.0  290  14  7   6.3   3.5 |  -4.6  23.7  300  10  5   5.1   2.8
 18000  -2.9  26.8  300  13  7   6.0   3.3 |  -3.9  25.0  305  10  5   5.0   2.8
 17500  -2.2  28.0  305  13  7   5.2   2.8 |  -3.2  26.2  305   9  5   4.8   2.6
 17000  -1.5  29.3  310  13  7   5.5   3.0 |  -2.5  27.5  310   9  5   4.8   2.6
 16500  -0.9  30.4  320  13  6   3.6   2.1 |  -1.8  28.8  310   9  5   4.5   2.5
 16000  -0.6  30.9  325  13  7   3.6   2.0 |  -1.2  29.8  310   9  5   4.5   2.5
 15500  -0.2  31.6  330  13  7   4.1   2.3 |  -0.1  31.8  315   9  5   5.7   3.1
 15000   0.8  33.4  335  15  8   4.5   2.5 |   0.7  33.3  320   9  5   5.6   3.1
 14500   1.5  34.7  335  16  8   7.3   4.0 |   1.5  34.7  325   9  5   6.1   3.4
 14000   2.7  36.9  340  16  8   8.1   4.5 |   2.4  36.3  330   9  5   6.2   3.4
 13500   3.8  38.8  340  16  8   6.9   3.8 |   3.2  37.8  335   9  5   5.5   3.0
 13000   4.6  40.3  340  15  8   5.3   2.9 |   3.9  39.0  340  10  5   5.0   2.7
 12500   5.3  41.5  335  15  8   5.0   2.7 |   4.6  40.3  345  10  5   5.0   2.7
 12000   5.9  42.6  335  14  7   4.4   2.4 |   5.3  41.5  355  10  5   5.1   2.8
 11500   6.5  43.7  335  14  7   4.5   2.5 |   6.0  42.8  360  10  5   5.4   3.0
 11000   7.2  45.0  340  13  7   4.8   2.6 |   6.8  44.2  005  11  6   6.1   3.3
 10500   7.9  46.2  340  12  6   3.6   2.0 |   7.7  45.9  015  12  6   3.7   2.0
 10250   8.1  46.6  345  12  6   3.6   2.0 |   7.8  46.0  015  12  6   2.9   1.6
 10000   8.4  47.1  345  12  6   6.5   3.6 |   8.2  46.8  015  12  6   6.9   3.8
  9750   8.9  48.0  350  12  6   7.4   4.0 |   8.7  47.7  020  13  6   7.8   4.3
  9500   9.4  48.9  350  12  6   6.2   3.4 |   9.2  48.6  025  13  7   6.2   3.4
  9250   9.7  49.5  355  13  6   3.8   2.1 |   9.5  49.1  025  13  7   3.9   2.1
  9000  10.0  50.0  355  13  7   5.3   2.9 |   9.8  49.6  025  13  7   5.9   3.2
  8750  10.5  50.9  360  14  7   7.3   4.0 |  10.3  50.5  025  13  7   7.4   4.0
  8500  11.0  51.8  005  14  7   6.4   3.5 |  10.8  51.4  025  13  7   7.3   4.0
  8250  11.4  52.5  005  15  8   5.9   3.3 |  11.3  52.3  020  12  6   7.6   4.2
  8000  11.8  53.2  010  16  8   6.1   3.4 |  11.8  53.2  015  12  6   8.3   4.5
  7750  12.3  54.1  010  16  8   6.5   3.6 |  12.4  54.3  015  11  6   9.8   5.4
  7500  12.7  54.9  015  17  9   6.7   3.7 |  13.1  55.6  015  11  6  10.1   5.5
  7250  13.2  55.8  015  15  8   6.9   3.8 |  13.8  56.8  010  11  6   9.8   5.4
  7000  13.6  56.5  015  13  7   6.6   3.6 |  14.5  58.1  010  11  6  10.8   5.9
  6750  14.1  57.4  020  11  6   7.7   4.2 |  15.3  59.5  010  11  6  11.8   6.4
  6500  14.7  58.5  020  10  5   9.6   5.3 |  16.1  61.0  010  11  6  10.9   6.0
  6250  15.4  59.7  020   9  5   9.9   5.5 |  16.9  62.4  010  11  6  10.1   5.6
  6000  16.2  61.2  020   9  5  10.3   5.7 |  17.7  63.9  005  11  6  11.3   6.2
  5750  17.1  62.8  020   8  4  14.2   7.8 |  18.7  65.7  005  11  6  17.9   9.8
  5500  18.3  64.9  020   8  4  19.2  10.5 |  20.3  68.5  010  10  5  25.8  14.1

           07/06/2015 at 1500 MDT          |       07/06/2015 at 1800 MDT
                                           |
K index... +27.8  LI... -1.0               | K index... +26.2  LI... -1.3
CAPE... +107.1  CIN... -4.0                | CAPE... +83.5  CIN... -18.4
                                           |
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 -64.7 -84.5  240  30 15   1.0   0.6 | -64.8 -84.6  240  29 15   1.2   0.7
 45000 -60.9 -77.6  230  47 24   5.2   2.9 | -60.7 -77.3  230  45 23   5.3   2.9
 40000 -52.1 -61.8  220  56 29   9.0   4.9 | -52.0 -61.6  220  50 26   8.8   4.8
 38000 -46.7 -52.1  220  48 25   9.0   4.9 | -46.7 -52.1  220  51 26   8.7   4.8
 36000 -41.3 -42.3  220  41 21   8.8   4.8 | -41.5 -42.7  220  51 26   8.5   4.7
 34000 -36.3 -33.3  230  35 18   8.4   4.6 | -36.7 -34.1  230  44 23   7.9   4.4
 32000 -31.3 -24.3  240  31 16   8.2   4.5 | -32.0 -25.6  245  38 20   7.7   4.2
 30000 -26.2 -15.2  245  24 13   7.4   4.1 | -26.9 -16.4  250  25 13   7.6   4.1
 29000 -24.0 -11.2  250  21 11   7.4   4.1 | -24.6 -12.3  255  19 10   7.6   4.2
 28000 -21.9  -7.4  250  19 10   6.6   3.6 | -22.5  -8.5  265  14  7   6.6   3.6
 27000 -19.9  -3.8  255  17  9   6.7   3.7 | -20.5  -4.9  270  12  6   6.7   3.7
 26000 -17.9  -0.2  260  16  8   6.7   3.7 | -18.5  -1.3  275  10  5   6.7   3.7
 25000 -16.0   3.2  265  14  7   6.5   3.6 | -16.6   2.1  285   9  5   6.8   3.7
 24000 -14.2   6.4  270  13  6   6.0   3.3 | -14.6   5.7  290   8  4   7.0   3.8
 23000 -12.5   9.5  275  11  6   6.0   3.3 | -12.5   9.5  295   7  4   7.0   3.9
 22000 -10.7  12.7  280   9  5   5.9   3.2 | -10.5  13.1  300   7  4   6.4   3.5
 21000  -9.1  15.6  280   8  4   5.6   3.1 |  -9.0  15.8  295   7  4   4.9   2.7
 20000  -7.5  18.5  280   8  4   5.6   3.1 |  -7.6  18.3  290   8  4   4.9   2.7
 19500  -6.7  19.9  280   7  4   5.6   3.1 |  -6.9  19.6  290   9  4   4.9   2.7
 19000  -5.9  21.4  280   7  4   5.8   3.2 |  -6.2  20.8  290   9  5   5.0   2.7
 18500  -5.1  22.8  285   7  4   5.9   3.2 |  -5.4  22.3  290   9  5   5.0   2.7
 18000  -4.3  24.3  285   7  4   5.8   3.2 |  -4.7  23.5  290  10  5   5.3   2.9
 17500  -3.5  25.7  290   7  4   5.6   3.1 |  -3.8  25.2  290  10  5   6.2   3.4
 17000  -2.7  27.1  295   7  4   5.7   3.1 |  -2.9  26.8  290  10  5   6.1   3.4
 16500  -1.9  28.6  295   7  4   4.5   2.5 |  -2.0  28.4  290   9  5   6.4   3.5
 16000  -0.9  30.4  300   6  3   4.4   2.4 |  -0.6  30.9  295   7  4   6.7   3.7
 15500  -0.2  31.6  305   5  2   5.5   3.0 |   0.2  32.4  295   6  3   4.8   2.6
 15000   0.6  33.1  320   4  2   5.4   3.0 |   0.9  33.6  290   4  2   5.0   2.7
 14500   1.3  34.3  340   3  2   5.6   3.1 |   1.6  34.9  285   2  1   5.4   3.0
 14000   2.1  35.8  015   3  1   5.7   3.1 |   2.3  36.1  290   1  0   5.6   3.0
 13500   2.9  37.2  045   4  2   5.6   3.1 |   3.1  37.6  090   1  0   5.9   3.2
 13000   3.7  38.7  055   6  3   5.6   3.1 |   3.9  39.0  065   2  1   6.1   3.3
 12500   4.5  40.1  060   8  4   5.6   3.1 |   4.8  40.6  060   4  2   6.0   3.3
 12000   5.3  41.5  055   8  4   5.5   3.0 |   5.6  42.1  055   4  2   5.9   3.3
 11500   6.0  42.8  050   8  4   5.8   3.2 |   6.4  43.5  050   5  3   5.9   3.2
 11000   6.9  44.4  050   9  5   6.4   3.5 |   7.3  45.1  050   6  3   5.7   3.1
 10500   7.9  46.2  045   9  5   4.4   2.4 |   8.1  46.6  050   7  3   3.9   2.1
 10250   8.1  46.6  045   9  5   3.1   1.7 |   8.3  46.9  050   7  4   3.6   1.9
 10000   8.4  47.1  045  10  5   6.8   3.7 |   8.7  47.7  050   7  4   7.3   4.0
  9750   9.0  48.2  045  10  5   8.0   4.4 |   9.2  48.6  050   8  4   8.5   4.7
  9500   9.5  49.1  045  10  5   6.7   3.7 |   9.8  49.6  045   8  4   6.7   3.7
  9250   9.9  49.8  040  10  5   5.3   2.9 |  10.1  50.2  045   9  4   4.2   2.3
  9000  10.3  50.5  035  10  5   6.1   3.3 |  10.5  50.9  045   9  5   5.4   2.9
  8750  10.7  51.3  030  10  5   7.1   3.9 |  10.9  51.6  040   9  5   6.6   3.6
  8500  11.2  52.2  030  10  5   6.1   3.4 |  11.4  52.5  040  10  5   5.8   3.2
  8250  11.6  52.9  025  11  6   5.6   3.1 |  11.7  53.1  035  10  5   5.5   3.0
  8000  12.0  53.6  020  12  6   5.6   3.1 |  12.1  53.8  035  11  6   5.6   3.1
  7750  12.4  54.3  015  12  6   5.0   2.7 |  12.5  54.5  030  11  6   5.6   3.1
  7500  12.7  54.9  015  13  7   4.4   2.4 |  12.9  55.2  030  11  6   5.5   3.0
  7250  12.9  55.2  010  13  7   4.2   2.3 |  13.3  55.9  025  11  6   5.7   3.1
  7000  13.2  55.8  005  14  7   4.0   2.2 |  13.6  56.5  020  10  5   5.2   2.8
  6750  13.5  56.3  360  15  8   5.9   3.2 |  14.0  57.2  010  10  5   7.2   4.0
  6500  14.0  57.2  355  15  8   7.9   4.3 |  14.7  58.5  010   9  5  10.2   5.6
  6250  14.6  58.3  350  15  7   7.5   4.1 |  15.4  59.7  005   9  5  10.3   5.7
  6000  15.1  59.2  340  14  7   8.5   4.7 |  16.2  61.2  005   9  4  10.3   5.7
  5750  16.0  60.8  340  14  7  17.1   9.4 |  17.0  62.6  360   8  4  14.2   7.8
  5500  17.7  63.9  335  13  7  28.0  15.4 |  18.3  64.9  360   8  4  20.3  11.1
________________________________________________________________________________

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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