Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 031318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0718 MDT Thursday, September 3, 2015

This forecast is for Thursday, September 3, 2015:

If the trigger temperature of 83.6 F/28.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 839 ft/min (4.3 m/s)
   Maximum height of thermals.................. 12767 ft MSL (7482 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7149 ft MSL (1864 ft AGL)
Thermal soaring outlook for Friday 09/04....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT).........
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18818 ft MSL (13533 ft AGL)
Wave soaring outlook for Friday 09/04.......... Poor

Remarks...

Sunrise/Sunset.................... 06:29:09 / 19:29:17 MDT
Total possible sunshine........... 13 hr 0 min 8 sec (780 min 8 sec)
Altitude of sun at 12:58:46 MDT... 57.69 degrees

Upper air data from rawinsonde observation taken on 09/03/2015 at 0600 MDT

Freezing level.................. 15654 ft MSL (10369 ft AGL)
Convective condensation level... 16801 ft MSL (11516 ft AGL)
Lifted condensation level....... 16365 ft MSL (11079 ft AGL)
Lifted index.................... -1.1
K index......................... +25.9

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  -64.5 -84.1   230   35   18   1.4   0.8   85.8 186.5    32.1      M    M
 45000  -60.5 -76.9   220   43   22  -0.8  -0.4   66.8 152.3    22.7      M    M
 40000  -54.9 -66.8   235   29   15   7.4   4.0   52.9 127.1    14.9      M    M
 38000  -51.2 -60.2   235   39   20   5.4   3.0   49.7 121.5    13.2      M    M
 36000  -46.1 -51.0   225   34   17   8.8   4.8   48.6 119.5    12.8      M    M
 34000  -40.8 -41.4   220   30   15   8.8   4.8   47.8 118.0    12.4      M    M
 32000  -35.5 -31.9   210   26   13   8.9   4.9   47.2 116.9    12.3      M    M
 30000  -30.1 -22.2   220   21   11   7.9   4.3   45.7 114.3    11.5      M    M
 29000  -27.8 -18.0   210   20   10   8.0   4.4   44.9 112.9    11.0      M    M
 28000  -25.3 -13.5   205   19   10   8.4   4.6   44.3 111.8    10.6      M    M
 27000  -23.2  -9.8   215   20   11   9.3   5.1   43.3 110.0     9.9      M    M
 26000  -20.6  -5.1   220   22   11   8.7   4.8   43.0 109.4     9.7      M    M
 25000  -18.5  -1.3   205   20   10   5.0   2.8   42.0 107.6     9.0      M    M
 24000  -17.8  -0.0   185   19   10   5.7   3.1   39.4 102.8     6.9      M    M
 23000  -15.9   3.4   185   24   12   8.5   4.7   38.1 100.6     5.9      M    M
 22000  -13.5   7.7   190   11    6   8.0   4.4   37.5  99.6     5.5      M    M
 21000  -11.0  12.2   200    8    4   7.9   4.3   36.9  98.5     5.1      M    M
 20000   -8.9  16.0   230    5    3   7.4   4.1   36.2  97.1     4.4      M    M
 19500   -8.1  17.4   200    8    4  -8.5  -4.6   35.3  95.6     3.7      M    M
 19000   -8.4  16.9   185   16    8  12.9   7.1   33.5  92.3     2.0      M    M
 18500   -7.2  19.0   185   17    9   8.6   4.7   33.2  91.8     1.7      M    M
 18000   -6.0  21.2   185   16    8   8.3   4.5   33.0  91.3     1.5      M    M
 17500   -4.8  23.4   185   16    8   8.2   4.5   32.7  90.9     1.2      M    M
 17000   -3.5  25.7   180   15    8   9.5   5.2   32.6  90.6     1.1      M    M
 16500   -2.0  28.4   180   14    7   8.6   4.7   32.6  90.6     1.1      M    M
 16000   -0.9  30.4   180   13    7   7.2   3.9   32.1  89.9     0.7      M    M
 15500    0.1  32.2   185   12    6   7.4   4.0   31.7  89.1     0.3      M    M
 15000    2.1  35.8   200   12    6   9.6   5.3   31.6  88.8     0.1      M    M
 14500    3.5  38.3   205   11    6   9.7   5.3   31.6  88.8     0.1      M    M
 14000    5.0  41.0   205   11    6   9.7   5.3   31.6  88.8     0.1      M    M
 13500    6.4  43.5   210   11    6   9.6   5.3   31.5  88.7     0.1      M    M
 13000    7.9  46.2   210   10    5   9.1   5.0   31.5  88.7     0.1      M    M
 12500    9.1  48.4   215    6    3   8.1   4.5   31.3  88.3    -0.2    603  3.1
 12000   10.3  50.5   230    3    1   8.1   4.5   31.0  87.8    -0.4    552  2.8
 11500   11.5  52.7   275    1    1   8.1   4.5   30.8  87.4    -0.7    501  2.5
 11000   12.7  54.9   335    2    1   8.1   4.5   30.5  86.9    -0.9    450  2.3
 10500   13.9  57.0   345    6    3   8.1   4.5   30.2  86.4    -1.2    399  2.0
 10250   14.5  58.1   340    7    4   8.2   4.5   30.1  86.2    -1.3    374  1.9
 10000   15.1  59.2   335    8    4   8.3   4.5   30.0  86.0    -1.5    349  1.8
  9750   15.7  60.3   330   10    5   8.2   4.5   29.9  85.8    -1.6    323  1.6
  9500   16.3  61.3   325   11    6   8.3   4.5   29.8  85.6    -1.7    298  1.5
  9250   16.9  62.4   320   12    6   8.3   4.5   29.7  85.4    -1.8    272  1.4
  9000   17.5  63.5   320   13    7   8.3   4.5   29.6  85.2    -1.9    246  1.3
  8750   18.1  64.6   320   15    8   8.3   4.5   29.4  85.0    -2.1    221  1.1
  8500   18.7  65.7   315   17    9   8.3   4.5   29.3  84.8    -2.2    195  1.0
  8250   19.3  66.7   315   18    9   8.3   4.5   29.2  84.6    -2.3    170  0.9
  8000   19.9  67.8   315   20   10   8.3   4.5   29.1  84.4    -2.5    144  0.7
  7750   20.5  68.9   315   18    9   8.2   4.5   29.0  84.2    -2.6    119  0.6
  7500   21.2  70.2   310   15    8   8.4   4.6   28.9  83.9    -2.7     93  0.5
  7250   21.8  71.2   310   13    7   8.0   4.4   28.7  83.7    -2.9     68  0.3
  7000   22.2  72.0   305   11    6   2.3   1.3   28.4  83.2    -3.2     48  0.2
  6750   22.1  71.8   300    9    5  -1.3  -0.7   27.7  81.8    -4.0     42  0.2
  6500   22.1  71.8   285    7    4  -0.7  -0.4   26.9  80.4    -4.8     36  0.2
  6250   22.0  71.6   270    6    3   0.6   0.3   26.1  79.0    -5.5     30  0.2
  6000   22.0  71.6   245    5    3  -4.9  -2.7   25.3  77.6    -6.3     24  0.1
  5750   21.2  70.2   240    3    2  -9.9  -5.4   23.9  75.0    -7.8     39  0.2
  5500   20.4  68.7   240    2    1 -11.5  -6.3   22.5  72.4    -9.4     56  0.3

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

           09/03/2015 at 0900 MDT          |       09/03/2015 at 1200 MDT
                                           |
K index... +29.4  LI... -1.1               | K index... +29.7  LI... -1.4
CAPE... +98.1  CIN... -27.7                | CAPE... +133.6  CIN... -30.5
                                           |
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 -63.6 -82.5  235  39 20   1.5   0.8 | -63.5 -82.3  230  40 20   1.5   0.8
 45000 -60.4 -76.7  235  43 22   3.2   1.8 | -60.6 -77.1  230  43 22   2.7   1.5
 40000 -55.0 -67.0  235  37 19   7.3   4.0 | -55.7 -68.3  245  39 20   8.1   4.4
 38000 -50.5 -58.9  235  38 19   7.5   4.1 | -50.7 -59.3  240  37 19   8.2   4.5
 36000 -46.0 -50.8  235  39 20   7.4   4.1 | -45.8 -50.4  235  34 18   8.2   4.5
 34000 -41.0 -41.8  230  35 18   8.6   4.7 | -40.6 -41.1  230  32 17   8.7   4.8
 32000 -35.8 -32.4  225  31 16   8.4   4.6 | -35.4 -31.7  220  31 16   8.5   4.7
 30000 -30.1 -22.2  220  28 14   8.5   4.7 | -29.7 -21.5  215  32 16   8.5   4.7
 29000 -27.6 -17.7  215  26 14   8.6   4.7 | -27.2 -17.0  215  32 16   8.5   4.7
 28000 -25.1 -13.2  210  25 13   7.3   4.0 | -24.7 -12.5  215  32 16   7.5   4.1
 27000 -23.0  -9.4  205  24 13   7.0   3.8 | -22.6  -8.7  215  30 15   7.2   3.9
 26000 -21.0  -5.8  205  24 12   7.0   3.8 | -20.5  -4.9  215  28 15   7.2   3.9
 25000 -19.0  -2.2  200  23 12   7.0   3.8 | -18.4  -1.1  210  27 14   7.2   3.9
 24000 -17.0   1.4  200  20 10   6.7   3.7 | -16.4   2.5  210  25 13   6.5   3.6
 23000 -15.0   5.0  195  17  9   6.7   3.7 | -14.5   5.9  205  23 12   6.5   3.6
 22000 -13.1   8.4  185  15  8   6.7   3.7 | -12.6   9.3  200  21 11   6.5   3.6
 21000 -11.2  11.8  185  13  7   6.6   3.6 | -10.7  12.7  195  21 11   6.5   3.5
 20000  -9.3  15.3  185  12  6   6.6   3.6 |  -8.9  16.0  190  22 11   6.5   3.6
 19500  -8.3  17.1  180  11  6   6.7   3.7 |  -7.9  17.8  190  22 11   6.5   3.6
 19000  -7.4  18.7  180  11  6   6.0   3.3 |  -7.0  19.4  185  22 11   6.0   3.3
 18500  -6.5  20.3  185  11  6   6.0   3.3 |  -6.2  20.8  185  23 12   5.9   3.3
 18000  -5.6  21.9  185  11  6   6.1   3.4 |  -5.3  22.5  180  23 12   6.0   3.3
 17500  -4.7  23.5  185  12  6   6.7   3.7 |  -4.5  23.9  180  24 12   6.1   3.3
 17000  -3.7  25.3  185  12  6   6.7   3.7 |  -3.6  25.5  180  24 12   6.0   3.3
 16500  -2.8  27.0  185  13  6   6.3   3.4 |  -2.7  27.1  175  24 12   7.0   3.8
 16000  -1.5  29.3  185  13  7   6.0   3.3 |  -1.1  30.0  175  24 12   7.1   3.9
 15500  -0.4  31.3  185  13  7   8.7   4.8 |  -0.1  31.8  170  23 12   7.6   4.2
 15000   0.9  33.6  185  13  7   8.5   4.7 |   1.0  33.8  170  21 11   7.6   4.2
 14500   2.2  36.0  185  13  6  10.3   5.7 |   2.1  35.8  170  20 10   7.7   4.2
 14000   3.8  38.8  185  12  6  10.9   6.0 |   3.3  37.9  165  17  9   7.7   4.2
 13500   5.4  41.7  185  12  6  10.0   5.5 |   4.4  39.9  165  15  8   8.0   4.4
 13000   6.7  44.1  190  11  5   9.0   4.9 |   5.6  42.1  165  12  6   8.4   4.6
 12500   8.1  46.6  190  10  5   8.7   4.8 |   6.9  44.4  165  10  5   8.5   4.6
 12000   9.3  48.7  190   8  4   7.9   4.3 |   8.2  46.8  170   7  4   8.5   4.7
 11500  10.5  50.9  190   6  3   7.9   4.3 |   9.4  48.9  175   5  3   8.5   4.6
 11000  11.7  53.1  195   4  2   7.6   4.2 |  10.7  51.3  185   3  2   7.8   4.3
 10500  12.9  55.2  210   1  1   5.3   2.9 |  11.9  53.4  245   1  1   5.1   2.8
 10250  13.2  55.8  235   1  0   6.5   3.5 |  12.2  54.0  280   2  1   6.6   3.6
 10000  13.9  57.0  320   1  1  10.4   5.7 |  13.0  55.4  295   2  1  11.4   6.3
  9750  14.6  58.3  340   3  1   9.5   5.2 |  13.7  56.7  305   3  2  10.3   5.6
  9500  15.4  59.7  345   4  2   9.2   5.1 |  14.5  58.1  310   4  2  10.1   5.5
  9250  16.0  60.8  345   5  3   8.1   4.4 |  15.2  59.4  315   5  2   8.9   4.9
  9000  16.6  61.9  340   6  3   8.8   4.9 |  15.8  60.4  315   5  3   9.6   5.3
  8750  17.3  63.1  335   7  4   9.7   5.3 |  16.6  61.9  320   6  3  10.4   5.7
  8500  18.0  64.4  335   8  4   9.2   5.0 |  17.3  63.1  320   7  3  10.0   5.5
  8250  18.7  65.7  330   9  5   8.7   4.8 |  18.0  64.4  320   7  4   9.5   5.2
  8000  19.2  66.6  330  11  5   8.0   4.4 |  18.7  65.7  320   8  4   9.4   5.2
  7750  19.8  67.6  330  11  6   7.6   4.1 |  19.4  66.9  320   8  4   9.4   5.2
  7500  20.3  68.5  325  12  6   7.6   4.1 |  20.1  68.2  320   8  4   9.8   5.4
  7250  20.8  69.4  325  13  7   7.5   4.1 |  20.9  69.6  320   8  4  10.5   5.8
  7000  21.3  70.3  320  14  7   7.4   4.1 |  21.6  70.9  320   8  4  10.3   5.7
  6750  21.8  71.2  320  15  8   7.6   4.2 |  22.4  72.3  320   8  4   9.6   5.3
  6500  22.3  72.1  315  16  8   4.3   2.4 |  23.1  73.6  320   8  4  10.3   5.7
  6250  22.5  72.5  315  13  7   2.0   1.1 |  23.9  75.0  320   8  4  11.5   6.3
  6000  22.6  72.7  310  11  5   1.6   0.9 |  24.7  76.5  315   8  4  10.3   5.7
  5750  22.7  72.9  305   8  4   2.4   1.3 |  25.5  77.9  315   8  4  12.8   7.0
  5500  23.1  73.6  280   5  2  10.5   5.8 |  26.8  80.2  315   7  4  22.4  12.3

           09/03/2015 at 1500 MDT          |       09/03/2015 at 1800 MDT
                                           |
K index... +30.2  LI... -1.1               | K index... +29.9  LI... -1.1
CAPE... +44.9  CIN... -23.7                | CAPE... +53.9  CIN... -25.5
                                           |
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 -64.0 -83.2  230  39 20   0.3   0.2 | -64.0 -83.2  230  40 21  -0.1  -0.1
 45000 -62.1 -79.8  235  46 24   3.6   2.0 | -62.2 -80.0  235  45 23   4.3   2.3
 40000 -55.7 -68.3  240  45 23   9.0   4.9 | -55.1 -67.2  250  35 18   8.9   4.9
 38000 -50.2 -58.4  240  45 23   9.2   5.0 | -49.7 -57.5  245  33 17   9.0   5.0
 36000 -44.7 -48.5  240  44 23   9.2   5.1 | -44.3 -47.7  235  31 16   9.1   5.0
 34000 -39.5 -39.1  235  40 20   8.6   4.7 | -39.0 -38.2  230  30 15   8.8   4.8
 32000 -34.4 -29.9  230  35 18   8.4   4.6 | -33.7 -28.7  230  29 15   8.8   4.8
 30000 -29.0 -20.2  225  33 17   7.9   4.3 | -28.3 -18.9  225  28 14   7.8   4.3
 29000 -26.6 -15.9  220  32 16   7.9   4.3 | -26.0 -14.8  225  28 14   7.9   4.3
 28000 -24.3 -11.7  220  31 16   7.3   4.0 | -23.7 -10.7  220  27 14   7.2   4.0
 27000 -22.2  -8.0  215  30 15   7.1   3.9 | -21.7  -7.1  220  27 14   6.9   3.8
 26000 -20.1  -4.2  215  28 15   7.2   3.9 | -19.6  -3.3  220  27 14   6.9   3.8
 25000 -18.0  -0.4  210  27 14   7.2   4.0 | -17.6   0.3  215  27 14   7.0   3.8
 24000 -16.1   3.0  205  26 13   6.7   3.7 | -15.7   3.7  215  27 14   6.4   3.5
 23000 -14.1   6.6  205  25 13   6.7   3.7 | -13.8   7.2  210  27 14   6.4   3.5
 22000 -12.2  10.0  200  24 12   6.7   3.7 | -12.0  10.4  210  27 14   6.5   3.6
 21000 -10.3  13.5  200  23 12   6.2   3.4 | -10.2  13.6  205  27 14   6.1   3.3
 20000  -8.5  16.7  195  24 12   6.2   3.4 |  -8.4  16.9  200  27 14   6.1   3.4
 19500  -7.6  18.3  190  24 12   6.3   3.4 |  -7.6  18.3  195  27 14   6.1   3.4
 19000  -6.8  19.8  190  24 12   6.1   3.3 |  -6.7  19.9  195  27 14   5.7   3.1
 18500  -5.9  21.4  185  24 12   6.0   3.3 |  -5.9  21.4  190  27 14   5.4   3.0
 18000  -5.0  23.0  185  24 12   6.1   3.3 |  -5.1  22.8  185  28 14   5.4   3.0
 17500  -4.1  24.6  180  24 12   6.3   3.5 |  -4.3  24.3  180  28 14   5.9   3.2
 17000  -3.2  26.2  180  24 12   6.3   3.5 |  -3.5  25.7  175  28 14   5.9   3.2
 16500  -2.3  27.9  175  23 12   6.3   3.5 |  -2.6  27.3  175  27 14   6.2   3.4
 16000  -0.9  30.4  165  22 11   6.3   3.5 |  -1.3  29.7  175  24 12   6.4   3.5
 15500   0.0  32.0  160  20 11   6.6   3.6 |  -0.4  31.3  175  22 11   6.6   3.6
 15000   1.0  33.8  155  18  9   6.6   3.6 |   0.6  33.1  170  19 10   6.6   3.6
 14500   1.9  35.4  145  16  8   6.9   3.8 |   1.5  34.7  165  16  8   6.8   3.7
 14000   2.9  37.2  135  13  7   7.1   3.9 |   2.5  36.5  165  14  7   6.9   3.8
 13500   4.0  39.2  125  11  6   7.6   4.2 |   3.5  38.3  160  12  6   6.9   3.8
 13000   5.2  41.4  120  10  5   8.7   4.7 |   4.5  40.1  155   9  5   6.7   3.7
 12500   6.5  43.7  115   9  5   8.6   4.7 |   5.4  41.7  155   7  4   6.7   3.7
 12000   7.7  45.9  110   7  4   7.9   4.3 |   6.3  43.3  155   5  2   5.6   3.1
 11500   8.8  47.8  095   5  3   7.9   4.4 |   7.1  44.8  175   2  1   5.7   3.1
 11000   9.9  49.8  070   4  2   7.1   3.9 |   7.9  46.2  270   2  1   4.9   2.7
 10500  10.9  51.6  025   4  2  10.3   5.6 |   8.6  47.5  290   5  3   4.0   2.2
 10250  11.8  53.2  005   5  2  11.6   6.4 |   8.9  48.0  295   6  3   4.2   2.3
 10000  12.5  54.5  355   6  3   8.2   4.5 |   9.3  48.7  295   8  4   6.9   3.8
  9750  13.2  55.8  350   7  4   9.2   5.0 |   9.9  49.8  300  10  5   7.4   4.1
  9500  13.8  56.8  345   8  4   8.7   4.8 |  10.4  50.7  300  11  6   7.3   4.0
  9250  14.4  57.9  340   9  5   8.4   4.6 |  10.9  51.6  305  13  7   6.2   3.4
  9000  15.1  59.2  340  10  5   9.4   5.1 |  11.4  52.5  305  14  7   7.0   3.8
  8750  15.8  60.4  340  11  5  10.1   5.6 |  12.0  53.6  310  16  8   8.5   4.7
  8500  16.6  61.9  335  11  6  10.0   5.5 |  12.5  54.5  310  17  9   8.2   4.5
  8250  17.3  63.1  335  12  6  10.2   5.6 |  13.1  55.6  310  18  9   8.5   4.7
  8000  18.1  64.6  335  13  7  10.1   5.5 |  13.8  56.8  315  18  9   8.7   4.8
  7750  18.8  65.8  335  13  7   9.9   5.5 |  14.4  57.9  315  18  9   8.6   4.7
  7500  19.6  67.3  335  13  7  10.0   5.5 |  15.0  59.0  315  19 10   9.1   5.0
  7250  20.3  68.5  335  13  7   9.9   5.4 |  15.8  60.4  315  19 10  10.0   5.5
  7000  21.0  69.8  335  14  7   9.9   5.4 |  16.5  61.7  315  19 10  10.1   5.6
  6750  21.8  71.2  335  14  7   9.5   5.2 |  17.2  63.0  315  19 10   9.9   5.4
  6500  22.5  72.5  330  14  7  10.3   5.6 |  18.0  64.4  315  19 10  10.3   5.6
  6250  23.3  73.9  330  14  7  11.4   6.2 |  18.8  65.8  315  18  9  10.8   5.9
  6000  24.1  75.4  330  14  7  10.4   5.7 |  19.5  67.1  315  18  9  10.2   5.6
  5750  24.9  76.8  330  14  7  12.7   7.0 |  20.3  68.5  315  18  9  11.4   6.3
  5500  26.2  79.2  330  13  7  22.3  12.2 |  21.3  70.3  315  16  8  16.2   8.9
________________________________________________________________________________

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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