Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 291208
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0608 MDT Monday, June 29, 2015

This forecast is for Monday, June 29, 2015:

If the trigger temperature of 82.1 F/27.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1351 ft/min (6.9 m/s)
   Maximum height of thermals.................. 17674 ft MSL (12367 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 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................. 10930 ft MSL (5623 ft AGL)
Thermal soaring outlook for Tuesday 06/30...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 40209 ft MSL (34902 ft AGL)
Wave soaring outlook for Tuesday 06/30......... Poor

Remarks...

Sunrise/Sunset.................... 05:34:17 / 20:31:32 MDT
Total possible sunshine........... 14 hr 57 min 15 sec (897 min 15 sec)
Altitude of sun at 13:02:58 MDT... 73.41 degrees

Upper air data from numerical model forecast valid on 06/29/2015 at 0600 MDT

Freezing level.................. 15749 ft MSL (10442 ft AGL)
Convective condensation level... 14903 ft MSL (9596 ft AGL)
Lifted condensation level....... 15489 ft MSL (10182 ft AGL)
Lifted index.................... -4.1
K index......................... +27.9

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.3 -81.9   010   24   12   3.7   2.0      M     M       M      M    M
 45000  -57.9 -72.2   360   33   17   2.7   1.5      M     M       M      M    M
 40000  -53.1 -63.6   360   53   27   6.3   3.5      M     M       M      M    M
 38000  -49.3 -56.7   360   55   28   6.3   3.5      M     M       M      M    M
 36000  -45.5 -49.9   360   57   29   6.4   3.5      M     M       M      M    M
 34000  -40.5 -40.9   360   55   28   8.6   4.7      M     M       M      M    M
 32000  -35.3 -31.5   005   53   27   8.6   4.7      M     M       M      M    M
 30000  -29.5 -21.1   360   48   25   8.5   4.7   46.1 115.0    10.6      M    M
 29000  -27.0 -16.6   355   45   23   8.6   4.7   45.7 114.3    10.4      M    M
 28000  -24.6 -12.3   355   43   22   6.2   3.4   45.2 113.3    10.1      M    M
 27000  -22.6  -8.7   350   40   21   6.5   3.6   43.8 110.8     9.1      M    M
 26000  -20.7  -5.3   345   38   20   6.5   3.6   42.6 108.7     8.2      M    M
 25000  -18.8  -1.8   340   36   18   6.3   3.4   41.5 106.7     7.4      M    M
 24000  -17.1   1.2   335   35   18   5.9   3.2   40.0 104.0     6.2      M    M
 23000  -15.4   4.3   330   34   17   6.0   3.3   38.6 101.5     5.0      M    M
 22000  -13.7   7.3   330   33   17   6.5   3.6   37.4  99.3     3.9      M    M
 21000  -11.7  10.9   325   31   16   6.8   3.7   36.2  97.2     2.9      M    M
 20000   -9.8  14.4   325   28   15   6.8   3.7   35.2  95.4     2.0      M    M
 19500   -8.8  16.2   325   27   14   6.8   3.8   34.7  94.5     1.6      M    M
 19000   -7.8  18.0   320   25   13   7.0   3.9   34.3  93.7     1.2      M    M
 18500   -6.8  19.8   320   23   12   7.1   3.9   33.8  92.8     0.7      M    M
 18000   -5.7  21.7   320   20   10   7.5   4.1   33.4  92.0     0.3      M    M
 17500   -4.6  23.7   320   19   10   7.8   4.3   33.0  91.4    -0.1   1143  5.8
 17000   -3.5  25.7   320   17    9   7.8   4.3   32.7  90.8    -0.4   1095  5.6
 16500   -2.2  28.0   325   16    8   8.7   4.7   32.4  90.4    -0.6   1043  5.3
 16000   -1.0  30.2   330   14    7   8.6   4.7   32.2  90.0    -0.8    990  5.0
 15500    1.0  33.8   335   11    6   8.7   4.8   32.0  89.5    -1.1    910  4.6
 15000    2.3  36.1   335    9    5   8.8   4.8   31.8  89.2    -1.2    856  4.3
 14500    3.5  38.3   340    8    4   8.1   4.4   31.6  88.8    -1.4    804  4.1
 14000    4.7  40.5   345    6    3   8.0   4.4   31.3  88.3    -1.7    753  3.8
 13500    6.0  42.8   345    4    2   9.3   5.1   31.1  88.0    -1.9    701  3.6
 13000    7.3  45.1   340    3    2   9.5   5.2   31.1  87.9    -2.0    645  3.3
 12500    8.7  47.7   340    3    1   8.8   4.9   31.0  87.8    -2.1    590  3.0
 12000    9.9  49.8   335    2    1   8.5   4.7   30.8  87.4    -2.4    539  2.7
 11500   11.1  52.0   320    1    1   8.0   4.4   30.6  87.1    -2.6    488  2.5
 11000   12.2  54.0   255    1    1   7.2   4.0   30.2  86.4    -3.0    439  2.2
 10500   13.4  56.1   225    2    1   3.0   1.7   29.9  85.8    -3.3    391  2.0
 10250   13.4  56.1   225    2    1   4.5   2.5   29.2  84.6    -4.0    381  1.9
 10000   14.1  57.4   220    3    1  11.2   6.1   29.2  84.6    -4.0    352  1.8
  9750   14.9  58.8   215    3    2  10.0   5.5   29.2  84.6    -4.0    323  1.6
  9500   15.6  60.1   215    4    2   8.0   4.4   29.2  84.6    -4.0    294  1.5
  9250   16.0  60.8   215    3    2   5.9   3.3   29.0  84.1    -4.3    273  1.4
  9000   16.6  61.9   210    3    2   8.8   4.9   28.8  83.8    -4.5    250  1.3
  8750   17.3  63.1   205    3    2  10.0   5.5   28.8  83.8    -4.5    221  1.1
  8500   18.0  64.4   205    3    1   8.4   4.6   28.8  83.8    -4.6    193  1.0
  8250   18.5  65.3   200    2    1   7.3   4.0   28.6  83.5    -4.8    169  0.9
  8000   19.1  66.4   195    1    1   7.8   4.3   28.4  83.2    -4.9    145  0.7
  7750   19.7  67.5   185    1    0   7.6   4.2   28.3  82.9    -5.1    120  0.6
  7500   20.2  68.4   000    0    0   6.9   3.8   28.1  82.6    -5.3     97  0.5
  7250   20.6  69.1   000    0    0   5.5   3.0   27.8  82.1    -5.6     77  0.4
  7000   21.1  70.0   000    0    0   8.9   4.9   27.6  81.6    -5.9     57  0.3
  6750   21.6  70.9   000    0    0   2.9   1.6   27.5  81.4    -6.1     32  0.2
  6500   21.2  70.2   360    1    1  -9.2  -5.0   26.4  79.5    -7.3     37  0.2
  6250   20.4  68.7   355    3    1 -10.8  -5.9   24.8  76.7    -8.9     55  0.3
  6000   19.5  67.1   350    4    2  -9.2  -5.0   23.3  74.0   -10.5     73  0.4
  5750   18.7  65.7   335    3    1  -9.7  -5.3   22.0  71.5   -12.1     91  0.5
  5500   17.6  63.7   290    1    1 -13.7  -7.5   20.3  68.6   -13.9    117  0.6

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

           06/29/2015 at 0900 MDT          |       06/29/2015 at 1200 MDT
                                           |
K index... +28.1  LI... -2.8               | K index... +28.4  LI... -4.2
CAPE... +406.9  CIN... -197.2              | CAPE... +990.2  CIN... -32.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.0 -81.4  360  26 13   3.7   2.0 | -62.5 -80.5  350  25 13   3.6   2.0
 45000 -57.8 -72.0  355  35 18   2.5   1.4 | -57.8 -72.0  350  39 20   1.8   1.0
 40000 -53.2 -63.8  010  51 26   6.2   3.4 | -54.1 -65.4  010  56 29   7.1   3.9
 38000 -49.5 -57.1  010  54 28   6.2   3.4 | -49.8 -57.6  010  56 29   7.1   3.9
 36000 -45.7 -50.3  010  57 29   6.5   3.6 | -45.6 -50.1  010  57 29   7.3   4.0
 34000 -40.5 -40.9  010  56 29   9.0   4.9 | -40.4 -40.7  015  55 28   8.9   4.9
 32000 -35.1 -31.2  010  55 29   8.9   4.9 | -34.4 -29.9  015  53 27   8.9   4.9
 30000 -29.4 -20.9  010  54 28   8.4   4.6 | -29.3 -20.7  010  52 27   8.4   4.6
 29000 -26.9 -16.4  005  54 28   8.5   4.6 | -26.8 -16.2  010  51 26   8.5   4.6
 28000 -24.5 -12.1  005  52 27   6.8   3.7 | -24.4 -11.9  010  51 26   7.4   4.1
 27000 -22.3  -8.1  005  49 25   7.0   3.8 | -22.1  -7.8  015  49 25   7.5   4.1
 26000 -20.2  -4.4  360  45 23   7.0   3.8 | -19.8  -3.6  015  48 25   7.5   4.1
 25000 -18.1  -0.6  360  42 22   6.2   3.4 | -17.6   0.3  015  47 24   6.6   3.6
 24000 -16.5   2.3  355  38 20   5.4   3.0 | -15.8   3.6  010  41 21   5.8   3.2
 23000 -15.0   5.0  350  35 18   5.6   3.1 | -14.1   6.6  005  36 19   5.8   3.2
 22000 -13.3   8.1  345  32 16   6.4   3.5 | -12.3   9.9  360  32 16   5.7   3.1
 21000 -11.4  11.5  340  31 16   6.9   3.8 | -10.7  12.7  355  29 15   5.8   3.2
 20000  -9.4  15.1  340  30 15   7.1   3.9 |  -9.0  15.8  350  26 13   6.2   3.4
 19500  -8.4  16.9  335  29 15   7.1   3.9 |  -8.2  17.2  345  25 13   6.5   3.6
 19000  -7.4  18.7  335  28 14   7.4   4.1 |  -7.2  19.0  345  24 12   7.4   4.0
 18500  -6.3  20.7  335  26 13   7.5   4.1 |  -6.2  20.8  340  23 12   7.4   4.0
 18000  -5.2  22.6  335  24 13   7.4   4.1 |  -5.2  22.6  340  22 11   7.6   4.2
 17500  -4.1  24.6  335  22 11   7.4   4.1 |  -4.1  24.6  340  21 11   7.7   4.2
 17000  -3.1  26.4  330  20 10   7.4   4.1 |  -3.0  26.6  340  21 11   7.8   4.3
 16500  -2.0  28.4  330  17  9   7.4   4.1 |  -1.3  29.7  335  18  9   8.2   4.5
 16000  -0.3  31.5  320  14  7   7.6   4.2 |  -0.1  31.8  335  17  9   8.0   4.4
 15500   0.8  33.4  320  12  6   8.1   4.4 |   1.0  33.8  330  15  8   7.5   4.1
 15000   2.0  35.6  320  11  5   8.0   4.4 |   2.1  35.8  330  13  7   7.5   4.1
 14500   3.2  37.8  315   9  4   9.2   5.1 |   3.3  37.9  325  11  5   8.4   4.6
 14000   4.6  40.3  315   7  3   9.1   5.0 |   4.5  40.1  320   8  4   8.3   4.6
 13500   5.9  42.6  315   5  2   9.1   5.0 |   5.8  42.4  315   6  3   8.7   4.8
 13000   7.3  45.1  310   3  2   9.1   5.0 |   7.1  44.8  310   5  2   8.8   4.8
 12500   8.6  47.5  295   2  1   8.8   4.8 |   8.4  47.1  305   3  2   8.9   4.9
 12000   9.8  49.6  285   2  1   8.7   4.8 |   9.7  49.5  300   3  1   9.0   4.9
 11500  11.1  52.0  265   1  1   8.4   4.6 |  11.0  51.8  290   2  1   8.5   4.7
 11000  12.3  54.1  255   1  1   8.1   4.4 |  12.2  54.0  285   1  0   8.0   4.4
 10500  13.5  56.3  245   1  1   3.5   1.9 |  13.4  56.1  000   0  0   3.0   1.7
 10250  13.6  56.5  250   1  1   4.9   2.7 |  13.5  56.3  000   0  0   4.8   2.7
 10000  14.4  57.9  245   1  1  11.1   6.1 |  14.2  57.6  110   1  0  11.5   6.3
  9750  15.1  59.2  245   1  1   9.8   5.4 |  14.9  58.8  105   1  0  10.0   5.5
  9500  15.8  60.4  240   1  1   7.3   4.0 |  15.6  60.1  100   1  1   8.2   4.5
  9250  16.1  61.0  230   1  1   5.1   2.8 |  16.1  61.0  100   1  1   6.8   3.7
  9000  16.6  61.9  220   1  1   8.0   4.4 |  16.7  62.1  105   1  1   9.0   5.0
  8750  17.3  63.1  195   1  1   9.0   4.9 |  17.4  63.3  105   2  1   9.5   5.2
  8500  17.9  64.2  175   1  1   7.6   4.2 |  18.1  64.6  100   2  1   7.8   4.3
  8250  18.4  65.1  150   1  0   6.9   3.8 |  18.6  65.5  090   2  1   6.6   3.6
  8000  18.9  66.0  120   1  0   7.4   4.1 |  19.1  66.4  080   2  1   7.5   4.1
  7750  19.5  67.1  080   1  0   6.6   3.6 |  19.6  67.3  065   2  1   8.7   4.8
  7500  19.8  67.6  055   1  1   4.1   2.2 |  20.1  68.2  055   2  1   9.6   5.3
  7250  20.0  68.0  030   1  1   2.9   1.6 |  20.8  69.4  045   3  1  10.0   5.5
  7000  20.2  68.4  010   1  1   4.3   2.4 |  21.5  70.7  040   3  2   9.8   5.4
  6750  20.5  68.9  355   2  1   2.0   1.1 |  22.2  72.0  040   3  2  10.1   5.5
  6500  20.3  68.5  340   2  1  -1.3  -0.7 |  22.9  73.2  035   3  2  10.6   5.8
  6250  20.1  68.2  325   2  1  -1.8  -1.0 |  23.7  74.7  035   3  2  10.4   5.7
  6000  19.9  67.8  310   2  1   0.9   0.5 |  24.5  76.1  030   3  2  11.0   6.1
  5750  20.3  68.5  300   2  1  11.5   6.3 |  25.5  77.9  030   3  2  17.1   9.4
  5500  21.5  70.7  300   2  1  20.6  11.3 |  27.0  80.6  035   3  2  25.1  13.8

           06/29/2015 at 1500 MDT          |       06/29/2015 at 1800 MDT
                                           |
K index... +23.7  LI... -3.6               | K index... +21.1  LI... -2.9
CAPE... +975.8  CIN... -9.3                | CAPE... +794.8  CIN... -14.5
                                           |
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 -62.0 -79.6  345  23 12   3.8   2.1 | -62.7 -80.9  335  24 12   3.8   2.1
 45000 -57.6 -71.7  355  38 20   1.1   0.6 | -58.1 -72.6  345  36 18   1.6   0.9
 40000 -54.6 -66.3  015  62 32   7.7   4.2 | -54.4 -65.9  005  54 28   8.0   4.4
 38000 -50.0 -58.0  015  57 29   7.7   4.2 | -49.5 -57.1  010  51 26   8.0   4.4
 36000 -45.4 -49.7  010  51 26   7.9   4.3 | -44.7 -48.5  015  48 25   8.1   4.4
 34000 -40.1 -40.2  015  49 25   8.9   4.9 | -39.1 -38.4  010  44 23   8.4   4.6
 32000 -34.1 -29.4  015  48 24   8.9   4.9 | -34.0 -29.2  010  41 21   8.8   4.8
 30000 -29.1 -20.4  010  45 23   8.3   4.6 | -28.8 -19.8  010  40 21   8.8   4.8
 29000 -26.6 -15.9  010  45 23   8.3   4.6 | -26.2 -15.2  010  40 21   8.8   4.8
 28000 -24.2 -11.6  010  44 22   7.6   4.2 | -23.6 -10.5  010  40 20   7.5   4.1
 27000 -21.9  -7.4  010  43 22   7.7   4.2 | -21.4  -6.5  010  39 20   7.6   4.2
 26000 -19.6  -3.3  010  42 22   7.7   4.2 | -19.1  -2.4  010  38 20   7.6   4.2
 25000 -17.3   0.9  010  42 21   6.8   3.7 | -16.8   1.8  010  38 19   7.2   4.0
 24000 -15.4   4.3  010  37 19   6.1   3.4 | -14.7   5.5  010  35 18   6.9   3.8
 23000 -13.6   7.5  010  33 17   6.2   3.4 | -12.6   9.3  010  32 17   6.9   3.8
 22000 -11.7  10.9  005  29 15   5.9   3.3 | -10.6  12.9  010  30 15   5.8   3.2
 21000 -10.0  14.0  360  28 14   5.8   3.2 |  -9.1  15.6  005  27 14   5.1   2.8
 20000  -8.2  17.2  355  27 14   5.9   3.2 |  -7.5  18.5  360  25 13   5.2   2.8
 19500  -7.4  18.7  350  26 13   6.0   3.3 |  -6.8  19.8  355  24 12   5.2   2.9
 19000  -6.4  20.5  350  25 13   6.9   3.8 |  -5.9  21.4  355  23 12   6.2   3.4
 18500  -5.5  22.1  350  24 13   7.0   3.8 |  -5.0  23.0  355  22 11   6.2   3.4
 18000  -4.5  23.9  350  24 12   7.5   4.1 |  -4.1  24.6  355  21 11   7.4   4.1
 17500  -3.4  25.9  350  22 11   7.7   4.2 |  -2.4  27.7  355  20 10   8.1   4.5
 17000  -1.7  28.9  350  20 10   7.7   4.2 |  -1.3  29.7  355  19 10   8.1   4.4
 16500  -0.5  31.1  355  19 10   7.7   4.2 |  -0.1  31.8  355  18  9   8.0   4.4
 16000   0.6  33.1  355  19 10   7.9   4.3 |   1.1  34.0  355  17  9   8.0   4.4
 15500   1.8  35.2  355  18  9   8.6   4.7 |   2.3  36.1  360  15  8   7.9   4.3
 15000   3.0  37.4  355  17  9   8.8   4.8 |   3.5  38.3  005  13  7   7.9   4.4
 14500   4.1  39.4  355  15  8   7.9   4.3 |   4.6  40.3  010  11  6   7.8   4.3
 14000   5.2  41.4  355  12  6   8.0   4.4 |   5.8  42.4  015   9  5   7.9   4.3
 13500   6.3  43.3  355  10  5   8.2   4.5 |   6.9  44.4  020   7  4   8.2   4.5
 13000   7.5  45.5  360   8  4   8.2   4.5 |   8.1  46.6  030   6  3   8.4   4.6
 12500   8.7  47.7  360   5  3   8.6   4.7 |   9.2  48.6  040   5  3   8.6   4.7
 12000  10.0  50.0  010   4  2   8.7   4.8 |  10.4  50.7  045   4  2   8.8   4.8
 11500  11.2  52.2  030   3  1   8.8   4.8 |  11.6  52.9  055   4  2   9.1   5.0
 11000  12.5  54.5  040   2  1   8.8   4.8 |  12.9  55.2  050   4  2   9.0   4.9
 10500  13.6  56.5  050   2  1   4.0   2.2 |  14.2  57.6  045   3  2   4.4   2.4
 10250  13.8  56.8  050   2  1   6.8   3.7 |  14.4  57.9  040   3  2   6.2   3.4
 10000  14.7  58.5  050   2  1  13.6   7.4 |  15.2  59.4  035   3  2  13.2   7.2
  9750  15.5  59.9  045   3  1  12.1   6.6 |  16.0  60.8  030   3  2  11.8   6.5
  9500  16.3  61.3  045   3  1   9.1   5.0 |  16.8  62.2  020   3  2   9.6   5.2
  9250  16.9  62.4  045   3  1   7.4   4.1 |  17.4  63.3  020   3  2   8.0   4.4
  9000  17.6  63.7  040   3  1  11.0   6.0 |  18.1  64.6  015   3  2  10.7   5.9
  8750  18.4  65.1  040   3  1  11.6   6.4 |  18.9  66.0  010   4  2  11.1   6.1
  8500  19.2  66.6  035   3  1  10.3   5.6 |  19.7  67.5  005   4  2  10.3   5.6
  8250  20.0  68.0  035   3  1   9.3   5.1 |  20.5  68.9  360   4  2   9.8   5.4
  8000  20.7  69.3  035   3  1  10.3   5.6 |  21.2  70.2  355   4  2   9.9   5.4
  7750  21.5  70.7  030   3  1  10.6   5.8 |  21.9  71.4  355   4  2   9.8   5.4
  7500  22.2  72.0  030   3  1   9.8   5.4 |  22.6  72.7  355   4  2   9.9   5.5
  7250  23.0  73.4  025   2  1   9.3   5.1 |  23.4  74.1  350   4  2   9.9   5.4
  7000  23.7  74.7  025   2  1  10.4   5.7 |  24.1  75.4  350   4  2  10.3   5.6
  6750  24.5  76.1  025   3  1  11.0   6.0 |  24.9  76.8  350   4  2  10.6   5.8
  6500  25.2  77.4  025   3  1  10.1   5.6 |  25.7  78.3  345   5  2  10.1   5.6
  6250  26.0  78.8  020   3  1   9.8   5.4 |  26.4  79.5  345   5  2  10.3   5.7
  6000  26.7  80.1  015   3  1  10.8   5.9 |  27.2  81.0  345   5  2   9.1   5.0
  5750  27.8  82.0  015   3  1  17.3   9.5 |  27.9  82.2  340   5  2  12.1   6.6
  5500  29.3  84.7  015   3  1  25.0  13.7 |  29.1  84.4  345   5  2  20.8  11.4
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613


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