Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 311218
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0618 MDT Monday, August 31, 2015

This forecast is for Monday, August 31, 2015:

If the trigger temperature of 82.9 F/28.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 183 ft/min (0.9 m/s)
   Maximum height of thermals.................. 12002 ft MSL (6717 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1200 MDT
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................. 6494 ft MSL (1209 ft AGL)
Thermal soaring outlook for Tuesday 09/01...... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13416 ft MSL (8131 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15387 ft MSL (10102 ft AGL)
Wave soaring outlook for Tuesday 09/01......... Fair

Remarks... None

Sunrise/Sunset.................... 06:26:21 / 19:33:58 MDT
Total possible sunshine........... 13 hr 7 min 37 sec (787 min 37 sec)
Altitude of sun at 12:59:43 MDT... 58.78 degrees

Upper air data from rawinsonde observation taken on 08/31/2015 at 0600 MDT

Freezing level.................. 16155 ft MSL (10870 ft AGL)
Convective condensation level... 16209 ft MSL (10924 ft AGL)
Lifted condensation level....... 14827 ft MSL (9541 ft AGL)
Lifted index.................... -0.0
K index......................... +23.6

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  -65.0 -85.0   280   32   16   4.7   2.6   83.5 182.3    31.9      M    M
 45000  -62.9 -81.2   240   40   21   5.4   3.0   62.6 144.8    21.2      M    M
 40000  -54.2 -65.6   240   39   20   6.9   3.8   53.5 128.3    16.5      M    M
 38000  -49.3 -56.7   230   35   18   9.0   4.9   52.2 125.9    16.0      M    M
 36000  -43.9 -47.0   230   34   18   9.0   5.0   51.4 124.6    15.9      M    M
 34000  -38.5 -37.3   230   29   15   9.6   5.3   50.7 123.3    15.8      M    M
 32000  -32.7 -26.9   230   22   12   7.9   4.3   49.8 121.7    15.6      M    M
 30000  -28.3 -18.9   235   27   14   4.4   2.4   47.9 118.2    14.4      M    M
 29000  -26.8 -16.2   235   31   16   7.0   3.8   46.1 115.0    13.2      M    M
 28000  -24.8 -12.6   235   34   17   7.0   3.8   45.0 113.0    12.4      M    M
 27000  -22.7  -8.9   240   33   17   7.0   3.9   43.8 110.9    11.6      M    M
 26000  -20.6  -5.1   240   31   16   7.0   3.9   42.8 109.1    10.9      M    M
 25000  -18.6  -1.5   245   30   15   7.5   4.1   41.9 107.5    10.3      M    M
 24000  -16.0   3.2   240   30   15   6.5   3.6   41.6 106.8    10.0      M    M
 23000  -14.5   5.9   235   30   15   5.2   2.9   39.8 103.6     8.7      M    M
 22000  -12.9   8.8   230   30   16   5.2   2.9   38.2 100.7     7.4      M    M
 21000  -11.3  11.7   225   31   16   6.9   3.8   36.7  98.1     6.2      M    M
 20000   -9.3  15.3   195   26   13   6.9   3.8   35.7  96.3     5.4      M    M
 19500   -8.3  17.1   190   26   13   7.0   3.8   35.2  95.4     4.9      M    M
 19000   -7.3  18.9   190   26   13   6.7   3.7   34.7  94.5     4.5      M    M
 18500   -6.3  20.7   190   24   13   7.0   3.9   34.2  93.5     4.0      M    M
 18000   -5.1  22.8   195   23   12   8.3   4.5   33.9  92.9     3.7      M    M
 17500   -3.9  25.0   195   22   11   8.3   4.5   33.6  92.5     3.5      M    M
 17000   -2.7  27.1   200   21   11   8.6   4.7   33.4  92.0     3.3      M    M
 16500   -1.3  29.7   200   20   10   9.6   5.3   33.3  91.9     3.2      M    M
 16000    0.8  33.4   205   19   10   9.6   5.3   33.3  91.9     3.2      M    M
 15500    2.2  36.0   210   18    9   9.6   5.3   33.2  91.8     3.2      M    M
 15000    3.6  38.5   220   17    9   9.6   5.3   33.2  91.7     3.2      M    M
 14500    5.1  41.2   225   16    8   9.5   5.2   33.2  91.7     3.1      M    M
 14000    6.0  42.8   230   15    8   4.4   2.4   32.7  90.9     2.7      M    M
 13500    6.8  44.2   245   13    7  -0.2  -0.1   32.0  89.5     2.0      M    M
 13000    7.0  44.6   260   11    6   8.9   4.9   30.7  87.3     0.8      M    M
 12500    8.1  46.6   280   11    5   7.3   4.0   30.3  86.5     0.3      M    M
 12000    9.1  48.4   295   11    6   7.0   3.8   29.9  85.8    -0.1    577  2.9
 11500   10.4  50.7   300   10    5  10.0   5.5   29.7  85.5    -0.3    524  2.7
 11000   11.8  53.2   310    9    5   9.7   5.3   29.7  85.5    -0.3    466  2.4
 10500   13.3  55.9   320    8    4   9.5   5.2   29.7  85.5    -0.3    408  2.1
 10250   13.9  57.0   320    8    4   9.0   4.9   29.7  85.4    -0.3    380  1.9
 10000   14.6  58.3   315    8    4   8.8   4.8   29.6  85.3    -0.4    353  1.8
  9750   15.2  59.4   315    8    4   8.9   4.9   29.5  85.1    -0.5    326  1.7
  9500   15.9  60.6   310    8    4   8.8   4.9   29.5  85.0    -0.6    299  1.5
  9250   16.5  61.7   310    8    4   8.9   4.9   29.4  84.9    -0.6    272  1.4
  9000   17.2  63.0   305    8    4   8.8   4.9   29.4  84.8    -0.7    245  1.2
  8750   17.9  64.2   295    8    4   8.9   4.9   29.3  84.7    -0.8    218  1.1
  8500   18.5  65.3   290    9    4   8.7   4.8   29.2  84.6    -0.9    191  1.0
  8250   19.2  66.6   280    9    5   9.5   5.2   29.1  84.4    -0.9    164  0.8
  8000   19.8  67.6   275   10    5   6.4   3.5   29.1  84.3    -1.0    137  0.7
  7750   20.0  68.0   275   10    5   0.0   0.0   28.5  83.4    -1.6    124  0.6
  7500   20.0  68.0   270   10    5   3.7   2.0   27.8  82.1    -2.3    117  0.6
  7250   20.5  68.9   270   11    6   8.6   4.7   27.7  81.8    -2.5     94  0.5
  7000   21.1  70.0   270   11    6   7.7   4.2   27.5  81.5    -2.6     69  0.4
  6750   21.7  71.1   275   11    6   8.2   4.5   27.4  81.3    -2.8     45  0.2
  6500   22.2  72.0   275   11    6   7.3   4.0   27.3  81.1    -3.0     20  0.1
  6250   22.6  72.7   280   11    6   2.9   1.6   26.9  80.5    -3.3      1  0.0
  6000   22.7  72.9   285   11    6   1.6   0.9   26.3  79.3    -4.0      M    M
  5750   22.8  73.0   280    6    3  -0.8  -0.4   25.7  78.2    -4.6      M    M
  5500   22.2  72.0   250    2    1 -17.2  -9.5   24.4  75.9    -6.0      M    M

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

           08/31/2015 at 0900 MDT          |       08/31/2015 at 1200 MDT
                                           |
K index... +28.3  LI... -1.2               | K index... +28.4  LI... -0.4
CAPE... +34.7  CIN... -15.5                | CAPE... +20.0  CIN... -41.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -64.7 -84.5  250  17  9   0.7   0.4 | -65.4 -85.7  225  22 12   0.7   0.4
 45000 -61.7 -79.1  240  27 14   4.8   2.6 | -62.1 -79.8  235  34 18   5.3   2.9
 40000 -54.0 -65.2  240  36 18   7.8   4.3 | -53.8 -64.8  235  40 21   7.7   4.2
 38000 -49.3 -56.7  240  34 17   7.8   4.3 | -49.1 -56.4  235  38 19   7.8   4.3
 36000 -44.6 -48.3  235  32 16   7.7   4.2 | -44.5 -48.1  235  35 18   7.7   4.2
 34000 -39.6 -39.3  235  30 15   8.4   4.6 | -39.5 -39.1  235  34 17   8.3   4.6
 32000 -33.9 -29.0  235  27 14   9.0   5.0 | -33.9 -29.0  235  32 17   8.9   4.9
 30000 -29.1 -20.4  240  25 13   8.2   4.5 | -28.9 -20.0  235  29 15   8.4   4.6
 29000 -26.6 -15.9  240  25 13   8.2   4.5 | -26.4 -15.5  235  27 14   8.4   4.6
 28000 -24.3 -11.7  240  24 12   7.2   3.9 | -23.9 -11.0  230  26 13   7.3   4.0
 27000 -22.2  -8.0  245  24 12   7.1   3.9 | -21.8  -7.2  235  25 13   7.2   4.0
 26000 -20.1  -4.2  245  23 12   7.1   3.9 | -19.7  -3.5  235  23 12   7.2   4.0
 25000 -18.0  -0.4  245  23 12   7.0   3.9 | -17.6   0.3  240  22 11   7.1   3.9
 24000 -16.0   3.2  240  24 12   6.6   3.6 | -15.7   3.7  240  22 11   6.4   3.5
 23000 -14.1   6.6  240  25 13   6.7   3.6 | -13.8   7.2  240  22 12   6.4   3.5
 22000 -12.2  10.0  235  26 13   6.3   3.5 | -12.0  10.4  240  23 12   6.3   3.5
 21000 -10.7  12.7  230  27 14   5.0   2.7 | -10.2  13.6  240  24 13   6.1   3.4
 20000  -9.2  15.4  220  28 14   5.0   2.8 |  -8.4  16.9  235  26 13   6.2   3.4
 19500  -8.5  16.7  215  29 15   5.0   2.7 |  -7.5  18.5  235  27 14   6.2   3.4
 19000  -7.7  18.1  215  29 15   5.7   3.1 |  -6.7  19.9  230  28 14   5.4   3.0
 18500  -6.9  19.6  210  29 15   5.8   3.2 |  -5.9  21.4  230  29 15   5.4   3.0
 18000  -6.0  21.2  210  29 15   6.0   3.3 |  -5.2  22.6  225  29 15   5.3   2.9
 17500  -5.1  22.8  210  29 15   6.7   3.7 |  -4.4  24.1  225  30 15   5.0   2.7
 17000  -4.2  24.4  210  28 15   6.6   3.6 |  -3.7  25.3  220  30 16   4.9   2.7
 16500  -2.6  27.3  210  27 14   7.4   4.1 |  -2.5  27.5  220  29 15   6.2   3.4
 16000  -1.6  29.1  215  25 13   7.4   4.0 |  -1.6  29.1  220  28 14   6.0   3.3
 15500  -0.5  31.1  210  22 11   8.0   4.4 |  -0.6  30.9  215  25 13   7.5   4.1
 15000   0.6  33.1  210  18  9   8.0   4.4 |   0.4  32.7  215  22 11   7.3   4.0
 14500   1.8  35.2  205  14  7   7.7   4.2 |   1.5  34.7  210  18  9   7.8   4.3
 14000   2.9  37.2  190  11  6   7.6   4.2 |   2.7  36.9  205  15  8   7.9   4.3
 13500   4.0  39.2  175   9  5   8.3   4.5 |   3.8  38.8  195  13  7   8.5   4.6
 13000   5.3  41.5  170   8  4   8.8   4.8 |   5.1  41.2  190  12  6   8.9   4.9
 12500   6.6  43.9  165   7  3   8.6   4.7 |   6.5  43.7  185  12  6   8.8   4.8
 12000   7.9  46.2  185   5  3   8.3   4.6 |   7.8  46.0  195  11  6   8.5   4.7
 11500   9.1  48.4  210   5  3   8.3   4.6 |   9.0  48.2  205  11  6   8.0   4.4
 11000  10.4  50.7  240   5  3   8.1   4.5 |  10.1  50.2  215  10  5   6.4   3.5
 10500  11.7  53.1  265   6  3   4.4   2.4 |  11.1  52.0  235  10  5   3.3   1.8
 10250  11.9  53.4  265   7  3   5.6   3.1 |  11.2  52.2  235  10  5   4.2   2.3
 10000  12.6  54.7  275   8  4  11.4   6.3 |  11.8  53.2  250   9  5   9.0   4.9
  9750  13.4  56.1  285   9  5  10.3   5.7 |  12.4  54.3  260   9  5   8.0   4.4
  9500  14.2  57.6  290  11  6   8.9   4.9 |  12.9  55.2  275   9  5   7.3   4.0
  9250  14.7  58.5  295  13  7   5.5   3.0 |  13.4  56.1  285   9  5   6.2   3.4
  9000  15.0  59.0  300  15  8   5.4   2.9 |  13.9  57.0  290   9  5   8.8   4.8
  8750  15.4  59.7  305  17  9   5.7   3.1 |  14.6  58.3  295   9  5  10.3   5.7
  8500  15.8  60.4  305  20 10   5.9   3.2 |  15.3  59.5  300   9  4   9.8   5.4
  8250  16.3  61.3  310  21 11   6.3   3.4 |  16.0  60.8  305   9  4   9.5   5.2
  8000  16.7  62.1  310  22 11   6.3   3.5 |  16.8  62.2  305   9  4   9.9   5.4
  7750  17.2  63.0  315  22 11   6.6   3.6 |  17.5  63.5  305   9  4  10.4   5.7
  7500  17.7  63.9  315  22 11   6.1   3.3 |  18.3  64.9  305   9  4  10.3   5.6
  7250  18.1  64.6  315  21 11   5.7   3.1 |  19.0  66.2  305   9  4  10.3   5.7
  7000  18.4  65.1  315  19 10   5.7   3.1 |  19.8  67.6  305   9  4  10.0   5.5
  6750  18.9  66.0  315  18  9   6.7   3.7 |  20.5  68.9  305   9  4   9.7   5.3
  6500  19.4  66.9  315  16  8   9.0   5.0 |  21.3  70.3  305   8  4  10.2   5.6
  6250  20.1  68.2  315  14  7  10.3   5.7 |  22.1  71.8  305   8  4  11.2   6.1
  6000  20.9  69.6  315  12  6   8.6   4.7 |  22.9  73.2  305   8  4   9.1   5.0
  5750  21.5  70.7  315  10  5  10.0   5.5 |  23.6  74.5  305   8  4  14.6   8.0
  5500  22.4  72.3  320   9  5  16.8   9.2 |  25.2  77.4  305   8  4  29.5  16.2

           08/31/2015 at 1500 MDT          |       08/31/2015 at 1800 MDT
                                           |
K index... +29.3  LI... -0.3               | K index... +22.6  LI... -0.0
CAPE... +20.9  CIN... -1.4                 | CAPE... 0.0  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 -65.3 -85.5  240  33 17   0.2   0.1 | -66.1 -87.0  250  34 17   0.0   0.0
 45000 -62.6 -80.7  240  45 23   5.3   2.9 | -63.4 -82.1  240  43 22   5.7   3.1
 40000 -54.2 -65.6  230  49 25   8.3   4.5 | -54.4 -65.9  220  43 22   8.5   4.7
 38000 -49.2 -56.6  230  47 24   8.3   4.6 | -49.3 -56.7  220  40 21   8.6   4.7
 36000 -44.2 -47.6  230  44 23   8.3   4.5 | -44.1 -47.4  220  37 19   8.6   4.7
 34000 -39.1 -38.4  230  39 20   8.4   4.6 | -39.0 -38.2  225  36 18   8.5   4.7
 32000 -33.4 -28.1  235  34 17   9.2   5.0 | -33.3 -27.9  225  35 18   9.1   5.0
 30000 -28.4 -19.1  235  28 14   8.6   4.7 | -28.5 -19.3  230  32 17   7.9   4.3
 29000 -25.8 -14.4  235  25 13   8.6   4.7 | -26.2 -15.2  230  31 16   7.9   4.3
 28000 -23.4 -10.1  235  22 11   7.0   3.9 | -23.9 -11.0  230  29 15   7.1   3.9
 27000 -21.3  -6.3  230  22 11   6.9   3.8 | -21.8  -7.2  235  28 14   7.0   3.8
 26000 -19.3  -2.7  230  22 11   6.9   3.8 | -19.8  -3.6  235  26 13   7.0   3.9
 25000 -17.2   1.0  230  21 11   6.9   3.8 | -17.7   0.1  235  24 12   7.0   3.8
 24000 -15.4   4.3  230  22 11   6.4   3.5 | -15.8   3.6  240  23 12   6.5   3.6
 23000 -13.5   7.7  230  22 11   6.4   3.5 | -13.8   7.2  245  22 11   6.6   3.6
 22000 -11.6  11.1  230  22 11   6.3   3.5 | -11.9  10.6  250  21 11   6.5   3.6
 21000  -9.9  14.2  230  21 11   5.9   3.3 | -10.1  13.8  255  20 10   6.2   3.4
 20000  -8.2  17.2  235  20 10   6.0   3.3 |  -8.3  17.1  265  19 10   6.2   3.4
 19500  -7.3  18.9  235  19 10   6.0   3.3 |  -7.4  18.7  270  19 10   6.2   3.4
 19000  -6.5  20.3  235  19 10   5.3   2.9 |  -6.4  20.5  270  18  9   6.6   3.6
 18500  -5.7  21.7  235  18  9   5.3   2.9 |  -5.4  22.3  280  18  9   6.6   3.6
 18000  -5.0  23.0  240  17  9   5.2   2.9 |  -4.4  24.1  285  17  9   6.7   3.7
 17500  -4.2  24.4  240  16  8   5.2   2.8 |  -3.4  25.9  290  16  8   7.1   3.9
 17000  -3.5  25.7  240  14  7   5.2   2.8 |  -2.4  27.7  300  14  7   7.2   3.9
 16500  -2.4  27.7  235  13  7   5.2   2.9 |  -1.0  30.2  315  13  6   5.8   3.2
 16000  -1.6  29.1  235  12  6   5.2   2.9 |  -0.2  31.6  320  12  6   5.8   3.2
 15500  -0.9  30.4  230  11  6   5.3   2.9 |   0.7  33.3  330  11  6   6.1   3.4
 15000  -0.1  31.8  225  10  5   5.3   2.9 |   1.5  34.7  330  11  5   6.1   3.4
 14500   0.7  33.3  220   9  5   6.0   3.3 |   2.4  36.3  335  10  5   6.0   3.3
 14000   1.6  34.9  220   9  4   6.3   3.4 |   3.3  37.9  335   9  4   6.0   3.3
 13500   2.5  36.5  220   8  4   6.5   3.6 |   4.1  39.4  335   7  4   6.2   3.4
 13000   3.5  38.3  240   7  3   6.8   3.7 |   5.1  41.2  335   7  3   6.5   3.6
 12500   4.5  40.1  265   6  3   7.3   4.0 |   6.0  42.8  330   6  3   6.6   3.6
 12000   5.6  42.1  280   7  3   8.1   4.4 |   7.0  44.6  325   5  3   6.9   3.8
 11500   6.8  44.2  295   8  4   8.4   4.6 |   8.0  46.4  320   5  2   6.9   3.8
 11000   8.1  46.6  300   8  4   9.0   5.0 |   9.1  48.4  320   4  2   7.0   3.8
 10500   9.5  49.1  300   9  4   4.4   2.4 |  10.1  50.2  315   4  2   4.4   2.4
 10250   9.6  49.3  300   9  5   6.3   3.5 |  10.3  50.5  315   4  2   4.7   2.6
 10000  10.5  50.9  300   9  5  13.8   7.6 |  10.9  51.6  310   4  2   9.3   5.1
  9750  11.5  52.7  300   9  5  12.3   6.8 |  11.6  52.9  310   3  2   9.4   5.1
  9500  12.4  54.3  300   9  5  10.7   5.9 |  12.2  54.0  300   3  1   8.1   4.5
  9250  13.0  55.4  300   9  5   8.1   4.5 |  12.7  54.9  290   2  1   5.7   3.1
  9000  13.7  56.7  300   9  5  10.3   5.7 |  13.1  55.6  265   2  1   6.8   3.7
  8750  14.5  58.1  300  10  5  12.0   6.6 |  13.7  56.7  225   2  1   8.1   4.5
  8500  15.4  59.7  300  10  5  10.5   5.8 |  14.2  57.6  200   2  1   7.6   4.2
  8250  16.1  61.0  300  10  5   9.4   5.2 |  14.7  58.5  190   3  2   7.6   4.2
  8000  16.8  62.2  300  10  5   9.8   5.4 |  15.3  59.5  185   5  2   7.2   4.0
  7750  17.6  63.7  300  10  5  10.1   5.6 |  15.8  60.4  180   6  3   6.8   3.7
  7500  18.4  65.1  300  10  5  10.3   5.6 |  16.3  61.3  180   8  4   5.8   3.2
  7250  19.1  66.4  300  11  5  10.4   5.7 |  16.6  61.9  180   9  5   5.1   2.8
  7000  19.9  67.8  300  11  5  10.3   5.7 |  17.0  62.6  185  11  5   4.9   2.7
  6750  20.7  69.3  300  11  6  10.6   5.8 |  17.3  63.1  185  12  6   5.8   3.2
  6500  21.5  70.7  300  11  6  10.8   5.9 |  17.8  64.0  185  13  7   8.6   4.7
  6250  22.3  72.1  300  11  6  11.6   6.4 |  18.5  65.3  185  13  7  10.4   5.7
  6000  23.1  73.6  300  11  6   8.7   4.8 |  19.2  66.6  180  13  7   8.1   4.4
  5750  23.8  74.8  300  11  6  13.8   7.6 |  19.7  67.5  180  13  7  11.6   6.3
  5500  25.4  77.7  300  11  6  30.5  16.8 |  21.0  69.8  180  12  6  22.9  12.6
________________________________________________________________________________

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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