Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210120
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1920 MDT Wednesday, August 20, 2014

This forecast is for Thursday, August 21, 2014:

If the trigger temperature of 77.4 F/25.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 955 ft/min (4.8 m/s)
   Maximum height of thermals.................. 16328 ft MSL (11041 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 0945 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................. 13811 ft MSL (8523 ft AGL)
Thermal soaring outlook for Friday 08/22....... 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)................ Neither
Potential height of wave....................... 40525 ft MSL (35238 ft AGL)
Wave soaring outlook for Friday 08/22.......... Poor

Remarks...

Sunrise/Sunset.................... 06:17:12 / 19:48:31 MDT
Total possible sunshine........... 13 hr 31 min 19 sec (811 min 19 sec)
Altitude of sun at 13:02:28 MDT... 62.17 degrees

Upper air data from numerical model forecast valid on 08/21/2014 at 0600 MDT

Freezing level.................. 15089 ft MSL (9802 ft AGL)
Convective condensation level... 15028 ft MSL (9741 ft AGL)
Lifted condensation level....... 15843 ft MSL (10556 ft AGL)
Lifted index.................... -1.1
K index......................... +17.1

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  -63.8 -82.8   225   34   18   1.0   0.6      M     M       M      M    M
 45000  -59.9 -75.8   230   50   26   5.8   3.2      M     M       M      M    M
 40000  -51.0 -59.8   230   62   32   7.1   3.9      M     M       M      M    M
 38000  -46.7 -52.1   235   63   32   7.1   3.9      M     M       M      M    M
 36000  -42.4 -44.3   240   64   33   7.1   3.9      M     M       M      M    M
 34000  -37.9 -36.2   240   62   32   7.5   4.1      M     M       M      M    M
 32000  -32.9 -27.2   235   58   30   7.3   4.0      M     M       M      M    M
 30000  -28.5 -19.3   235   52   27   7.2   4.0   47.9 118.2    12.7      M    M
 29000  -26.3 -15.3   230   49   25   7.2   4.0   47.0 116.5    12.2      M    M
 28000  -24.2 -11.6   230   47   24   6.8   3.7   46.1 115.0    11.7      M    M
 27000  -22.2  -8.0   230   43   22   6.5   3.6   44.8 112.6    10.7      M    M
 26000  -20.3  -4.5   230   39   20   6.5   3.6   43.5 110.3     9.9      M    M
 25000  -18.3  -0.9   230   35   18   6.5   3.6   42.4 108.4     9.1      M    M
 24000  -16.4   2.5   230   32   17   6.3   3.5   41.1 106.0     8.1      M    M
 23000  -14.6   5.7   230   30   16   6.4   3.5   39.8 103.7     7.1      M    M
 22000  -12.7   9.1   235   29   15   6.5   3.6   38.7 101.7     6.2      M    M
 21000  -10.9  12.4   235   27   14   6.0   3.3   37.4  99.3     5.1      M    M
 20000   -9.1  15.6   240   25   13   6.0   3.3   36.0  96.9     4.0      M    M
 19500   -8.2  17.2   240   24   13   6.0   3.3   35.4  95.8     3.5      M    M
 19000   -7.3  18.9   240   24   12   6.4   3.5   34.8  94.7     3.0      M    M
 18500   -6.3  20.7   245   23   12   6.5   3.6   34.3  93.7     2.5      M    M
 18000   -5.4  22.3   245   22   11   6.5   3.6   33.7  92.7     2.0      M    M
 17500   -4.4  24.1   245   21   11   6.3   3.4   33.1  91.6     1.5      M    M
 17000   -3.5  25.7   245   20   11   6.3   3.5   32.5  90.6     1.0      M    M
 16500   -2.6  27.3   245   20   10   5.9   3.2   31.9  89.5     0.4      M    M
 16000   -1.4  29.5   240   19   10   5.8   3.2   30.9  87.7    -0.6    920  4.7
 15500   -0.6  30.9   235   18    9   6.5   3.6   30.3  86.5    -1.2    880  4.5
 15000    0.4  32.7   235   18    9   6.6   3.6   29.8  85.6    -1.8    838  4.3
 14500    1.3  34.3   230   17    9   6.9   3.8   29.3  84.7    -2.4    796  4.0
 14000    2.2  36.0   225   16    8   7.2   3.9   28.8  83.9    -2.9    752  3.8
 13500    3.2  37.8   225   15    8   7.4   4.1   28.4  83.1    -3.4    708  3.6
 13000    4.3  39.7   225   13    7   7.7   4.2   28.1  82.5    -3.8    660  3.4
 12500    5.5  41.9   225   11    6   7.8   4.3   27.8  82.0    -4.1    610  3.1
 12000    6.8  44.2   230    8    4   8.3   4.6   27.5  81.5    -4.3    557  2.8
 11500    8.1  46.6   245    6    3   8.3   4.6   27.3  81.1    -4.4    502  2.6
 11000    9.4  48.9   275    5    3   8.4   4.6   27.1  80.7    -4.6    448  2.3
 10500   10.7  51.3   300    7    3   5.1   2.8   26.9  80.4    -4.8    395  2.0
 10250   10.9  51.6   310    7    4   5.4   3.0   26.4  79.5    -5.3    380  1.9
 10000   11.6  52.9   315    9    4  10.5   5.8   26.3  79.4    -5.4    353  1.8
  9750   12.3  54.1   315   10    5   9.7   5.3   26.3  79.4    -5.4    325  1.7
  9500   13.0  55.4   320   12    6   9.3   5.1   26.3  79.4    -5.5    297  1.5
  9250   13.5  56.3   320   14    7   6.6   3.6   26.2  79.2    -5.7    273  1.4
  9000   14.0  57.2   315   15    8   6.5   3.6   25.9  78.7    -6.0    252  1.3
  8750   14.5  58.1   315   17    9   8.0   4.4   25.8  78.4    -6.2    229  1.2
  8500   15.0  59.0   315   19   10   6.9   3.8   25.6  78.1    -6.4    205  1.0
  8250   15.5  59.9   310   20   10   5.4   3.0   25.3  77.6    -6.7    185  0.9
  8000   15.8  60.4   310   20   10   5.0   2.7   24.9  76.9    -7.1    167  0.8
  7750   16.2  61.2   305   20   10   5.2   2.9   24.6  76.3    -7.5    150  0.8
  7500   16.5  61.7   305   19   10   4.9   2.7   24.2  75.6    -7.9    132  0.7
  7250   16.8  62.2   305   17    9   4.4   2.4   23.8  74.9    -8.4    115  0.6
  7000   17.1  62.8   305   14    7   4.6   2.5   23.4  74.2    -8.8     98  0.5
  6750   17.5  63.5   305   12    6   4.8   2.6   23.1  73.5    -9.2     81  0.4
  6500   17.8  64.0   305    9    5   3.6   2.0   22.6  72.8    -9.7     64  0.3
  6250   17.9  64.2   305    7    3   1.9   1.0   22.1  71.8   -10.3     53  0.3
  6000   18.0  64.4   300    5    2   4.5   2.5   21.6  70.8   -10.9     41  0.2
  5750   18.3  64.9   290    3    1   0.9   0.5   21.2  70.1   -11.4     25  0.1
  5500   17.6  63.7   235    2    1 -13.7  -7.5   20.0  68.0   -12.8     38  0.2

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

           08/21/2014 at 0900 MDT          |       08/21/2014 at 1200 MDT
                                           |
K index... +16.1  LI... +1.6               | K index... +14.3  LI... +0.2
CAPE... 0.0  CIN... -0.7                   | 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 -64.0 -83.2  225  38 19   0.9   0.5 | -63.8 -82.8  220  40 20   0.8   0.4
 45000 -60.4 -76.7  225  53 27   5.6   3.1 | -60.4 -76.7  220  58 30   5.4   3.0
 40000 -51.6 -60.9  230  63 32   7.5   4.1 | -52.0 -61.6  230  66 34   7.3   4.0
 38000 -47.1 -52.8  230  63 32   7.5   4.1 | -47.5 -53.5  230  66 34   7.4   4.1
 36000 -42.6 -44.7  235  62 32   7.5   4.1 | -43.1 -45.6  230  65 33   7.4   4.0
 34000 -38.3 -36.9  235  60 31   6.9   3.8 | -37.9 -36.2  230  62 32   7.8   4.3
 32000 -33.7 -28.7  240  57 29   6.7   3.7 | -33.2 -27.8  230  60 31   7.7   4.2
 30000 -29.3 -20.7  235  52 27   7.4   4.0 | -29.2 -20.6  230  54 28   6.5   3.6
 29000 -27.1 -16.8  230  49 25   7.4   4.0 | -27.2 -17.0  230  51 26   6.5   3.6
 28000 -24.8 -12.6  230  46 24   7.1   3.9 | -25.3 -13.5  235  48 25   7.1   3.9
 27000 -22.8  -9.0  230  43 22   7.0   3.8 | -23.0  -9.4  235  44 23   7.3   4.0
 26000 -20.7  -5.3  235  39 20   7.0   3.8 | -20.8  -5.4  235  40 20   7.4   4.0
 25000 -18.6  -1.5  235  35 18   7.0   3.8 | -18.6  -1.5  235  36 18   7.4   4.0
 24000 -16.5   2.3  235  33 17   6.8   3.7 | -16.6   2.1  235  33 17   6.6   3.6
 23000 -14.5   5.9  240  30 16   6.8   3.8 | -14.6   5.7  240  30 16   6.6   3.6
 22000 -12.5   9.5  240  28 15   6.8   3.7 | -12.6   9.3  245  28 14   6.6   3.6
 21000 -10.6  12.9  245  27 14   6.0   3.3 | -10.8  12.6  250  26 13   6.1   3.3
 20000  -8.8  16.2  250  26 14   6.0   3.3 |  -9.0  15.8  255  25 13   6.1   3.3
 19500  -7.9  17.8  250  26 13   6.0   3.3 |  -8.1  17.4  255  24 12   6.1   3.4
 19000  -7.0  19.4  255  25 13   5.9   3.2 |  -7.2  19.0  260  23 12   5.8   3.2
 18500  -6.2  20.8  255  24 13   5.9   3.3 |  -6.3  20.7  260  23 12   5.8   3.2
 18000  -5.4  22.3  260  23 12   6.1   3.4 |  -5.5  22.1  265  22 11   5.8   3.2
 17500  -4.5  23.9  260  22 11   6.8   3.7 |  -4.6  23.7  265  21 11   5.9   3.2
 17000  -3.5  25.7  260  20 10   6.8   3.7 |  -3.4  25.9  270  19 10   6.3   3.4
 16500  -2.6  27.3  260  19 10   5.8   3.2 |  -2.4  27.7  270  18  9   7.2   4.0
 16000  -1.4  29.5  260  17  9   5.7   3.1 |  -1.4  29.5  270  18  9   7.4   4.0
 15500  -0.6  30.9  260  16  8   5.9   3.2 |  -0.4  31.3  270  17  9   6.2   3.4
 15000   0.3  32.5  255  15  8   5.9   3.2 |   0.5  32.9  270  17  9   6.3   3.5
 14500   1.2  34.2  255  14  7   6.0   3.3 |   1.4  34.5  270  16  8   6.2   3.4
 14000   2.0  35.6  250  13  7   6.1   3.3 |   2.3  36.1  270  14  7   6.2   3.4
 13500   2.9  37.2  245  12  6   6.5   3.6 |   3.2  37.8  270  13  7   6.5   3.6
 13000   3.9  39.0  245   9  5   7.2   3.9 |   4.2  39.6  265  11  6   6.8   3.7
 12500   5.0  41.0  250   7  3   7.5   4.1 |   5.1  41.2  260  10  5   7.3   4.0
 12000   6.2  43.2  265   4  2   8.6   4.7 |   6.4  43.5  255   8  4   8.5   4.7
 11500   7.5  45.5  320   3  2   8.7   4.8 |   7.6  45.7  250   6  3   8.7   4.8
 11000   8.9  48.0  340   5  2   9.1   5.0 |   9.0  48.2  250   5  3   9.2   5.1
 10500  10.3  50.5  350   7  3   5.0   2.7 |  10.5  50.9  255   4  2   5.3   2.9
 10250  10.5  50.9  350   7  4   5.2   2.8 |  10.7  51.3  255   4  2   6.1   3.3
 10000  11.2  52.2  345   8  4  11.4   6.3 |  11.5  52.7  265   4  2  11.9   6.5
  9750  12.0  53.6  340  10  5  10.6   5.8 |  12.3  54.1  275   3  2  10.6   5.8
  9500  12.8  55.0  335  11  6   9.8   5.4 |  13.1  55.6  285   3  2  10.0   5.5
  9250  13.4  56.1  335  12  6   7.4   4.1 |  13.7  56.7  295   3  2   8.3   4.6
  9000  13.9  57.0  330  13  7   7.7   4.2 |  14.4  57.9  305   3  2   8.9   4.9
  8750  14.5  58.1  325  14  7   8.7   4.8 |  15.0  59.0  315   3  2   9.7   5.3
  8500  15.1  59.2  325  16  8   7.5   4.1 |  15.7  60.3  320   3  2   8.5   4.6
  8250  15.6  60.1  320  17  9   6.5   3.6 |  16.2  61.2  325   2  1   7.0   3.8
  8000  16.0  60.8  315  18  9   5.7   3.1 |  16.6  61.9  325   2  1   8.1   4.4
  7750  16.3  61.3  315  18  9   4.8   2.6 |  17.2  63.0  310   1  0   9.2   5.1
  7500  16.6  61.9  310  19 10   4.2   2.3 |  17.8  64.0  285   1  0   9.5   5.2
  7250  16.9  62.4  310  16  8   3.8   2.1 |  18.5  65.3  280   1  0   9.7   5.3
  7000  17.1  62.8  305  14  7   3.6   2.0 |  19.2  66.6  275   1  0  10.0   5.5
  6750  17.3  63.1  300  11  6   3.7   2.0 |  20.0  68.0  275   1  0  10.9   6.0
  6500  17.6  63.7  295   8  4   5.9   3.2 |  20.8  69.4  275   1  0  10.9   6.0
  6250  18.1  64.6  280   6  3   7.8   4.3 |  21.6  70.9  270   1  0  11.5   6.3
  6000  18.6  65.5  260   4  2   5.1   2.8 |  22.4  72.3  265   1  0   8.5   4.6
  5750  18.9  66.0  215   4  2   8.6   4.7 |  23.1  73.6  270   1  0  13.0   7.2
  5500  19.9  67.8  210   4  2  21.2  11.7 |  24.7  76.5  275   1  0  29.9  16.4

           08/21/2014 at 1500 MDT          |       08/21/2014 at 1800 MDT
                                           |
K index... +21.3  LI... +0.2               | K index... +28.2  LI... -1.0
CAPE... 0.0  CIN... M                      | CAPE... +20.9  CIN... -32.8
                                           |
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 -64.5 -84.1  225  45 23   1.6   0.9 | -64.3 -83.7  230  42 22   1.9   1.0
 45000 -60.3 -76.5  225  63 32   5.4   2.9 | -60.0 -76.0  230  60 31   5.0   2.7
 40000 -51.6 -60.9  225  65 34   6.9   3.8 | -51.7 -61.1  225  68 35   7.1   3.9
 38000 -47.5 -53.5  230  65 33   6.8   3.8 | -47.4 -53.3  230  65 34   7.1   3.9
 36000 -43.4 -46.1  235  64 33   7.0   3.8 | -43.2 -45.8  230  64 33   7.3   4.0
 34000 -38.4 -37.1  235  61 32   8.4   4.6 | -38.2 -36.8  230  59 30   8.4   4.6
 32000 -33.3 -27.9  235  58 30   8.3   4.5 | -33.2 -27.8  230  54 28   8.3   4.5
 30000 -28.7 -19.7  230  53 27   7.8   4.3 | -28.6 -19.5  235  48 24   7.6   4.2
 29000 -26.4 -15.5  230  50 26   7.8   4.3 | -26.3 -15.3  235  44 23   7.6   4.2
 28000 -24.0 -11.2  230  47 24   7.2   4.0 | -23.5 -10.3  240  40 21   6.6   3.6
 27000 -21.6  -6.9  230  43 22   6.3   3.5 | -21.6  -6.9  240  38 19   6.7   3.7
 26000 -19.7  -3.5  230  39 20   6.4   3.5 | -19.6  -3.3  240  35 18   6.7   3.7
 25000 -17.7   0.1  230  35 18   6.4   3.5 | -17.6   0.3  240  32 17   6.5   3.6
 24000 -15.8   3.6  235  33 17   6.6   3.6 | -15.9   3.4  240  29 15   5.9   3.3
 23000 -13.8   7.2  240  30 16   6.6   3.6 | -14.2   6.4  240  26 13   6.0   3.3
 22000 -11.9  10.6  245  28 15   6.0   3.3 | -12.5   9.5  245  23 12   5.9   3.2
 21000 -10.4  13.3  250  27 14   4.8   2.6 | -10.8  12.6  245  21 11   5.6   3.1
 20000  -9.0  15.8  250  25 13   4.8   2.6 |  -9.2  15.4  250  19 10   5.6   3.1
 19500  -8.3  17.1  255  25 13   4.7   2.6 |  -8.4  16.9  250  18  9   5.6   3.1
 19000  -7.5  18.5  255  24 12   6.8   3.7 |  -7.6  18.3  250  18  9   6.0   3.3
 18500  -6.6  20.1  255  24 12   6.7   3.7 |  -6.7  19.9  250  17  9   6.0   3.3
 18000  -5.6  21.9  260  24 12   7.1   3.9 |  -5.9  21.4  250  16  8   6.2   3.4
 17500  -4.5  23.9  260  23 12   7.7   4.2 |  -4.9  23.2  250  15  8   6.5   3.6
 17000  -3.5  25.7  265  22 11   7.8   4.3 |  -4.0  24.8  250  15  8   6.3   3.5
 16500  -2.4  27.7  265  21 11   7.8   4.3 |  -2.9  26.8  250  15  8   8.4   4.6
 16000  -1.3  29.7  270  21 11   7.9   4.3 |  -1.7  28.9  250  14  7   8.3   4.5
 15500  -0.2  31.6  270  20 10   8.0   4.4 |  -0.5  31.1  250  14  7   8.2   4.5
 15000   1.0  33.8  270  18  9   8.0   4.4 |   0.7  33.3  250  13  7   8.2   4.5
 14500   2.1  35.8  275  17  9   8.0   4.4 |   1.9  35.4  250  13  7   8.4   4.6
 14000   3.8  38.8  275  15  8   7.8   4.3 |   3.8  38.8  240  12  6   8.8   4.8
 13500   4.9  40.8  280  13  7   7.4   4.1 |   5.1  41.2  235  11  6   8.8   4.8
 13000   6.0  42.8  280  11  6   7.2   4.0 |   6.4  43.5  220  10  5   8.8   4.8
 12500   7.1  44.8  280   9  5   7.3   4.0 |   7.7  45.9  205   9  4   8.6   4.7
 12000   8.2  46.8  265   6  3   7.5   4.1 |   9.0  48.2  195   8  4   8.4   4.6
 11500   9.3  48.7  235   4  2   7.6   4.2 |  10.2  50.4  180   7  4   8.6   4.7
 11000  10.5  50.9  200   4  2   7.7   4.2 |  11.6  52.9  175   7  4   8.8   4.8
 10500  11.7  53.1  175   5  3   4.6   2.5 |  12.9  55.2  165   6  3   5.3   2.9
 10250  11.9  53.4  175   6  3   6.2   3.4 |  13.2  55.8  165   6  3   6.6   3.6
 10000  12.7  54.9  175   6  3  11.4   6.2 |  14.0  57.2  165   6  3  12.2   6.7
  9750  13.4  56.1  170   6  3  10.3   5.6 |  14.8  58.6  160   6  3  11.3   6.2
  9500  14.1  57.4  170   6  3   9.5   5.2 |  15.6  60.1  160   6  3   9.6   5.3
  9250  14.8  58.6  170   6  3   8.8   4.8 |  16.2  61.2  160   5  3   7.9   4.3
  9000  15.5  59.9  170   6  3  10.5   5.8 |  16.9  62.4  160   5  3   9.9   5.4
  8750  16.3  61.3  170   6  3  11.2   6.1 |  17.7  63.9  160   5  3  10.5   5.8
  8500  17.1  62.8  170   6  3  10.5   5.8 |  18.4  65.1  160   5  2  10.2   5.6
  8250  17.8  64.0  170   6  3   9.8   5.4 |  19.2  66.6  160   4  2  10.0   5.5
  8000  18.6  65.5  170   6  3  10.0   5.5 |  19.9  67.8  160   4  2   9.7   5.3
  7750  19.3  66.7  170   6  3  10.1   5.6 |  20.6  69.1  160   4  2   9.2   5.1
  7500  20.1  68.2  170   6  3  10.1   5.6 |  21.3  70.3  160   4  2   9.9   5.4
  7250  20.8  69.4  170   5  3  10.2   5.6 |  22.1  71.8  160   4  2  10.5   5.8
  7000  21.6  70.9  170   5  3  10.1   5.5 |  22.8  73.0  160   4  2   9.8   5.4
  6750  22.3  72.1  170   5  3  10.0   5.5 |  23.5  74.3  160   3  2   9.1   5.0
  6500  23.1  73.6  170   5  3  10.3   5.6 |  24.2  75.6  160   3  2  10.0   5.5
  6250  23.9  75.0  170   5  3  10.9   6.0 |  25.0  77.0  160   3  2  10.9   6.0
  6000  24.7  76.5  170   5  3   9.2   5.0 |  25.8  78.4  165   3  1   9.9   5.5
  5750  25.4  77.7  170   5  3  14.0   7.7 |  26.6  79.9  165   3  1  10.9   6.0
  5500  27.0  80.6  170   5  3  27.6  15.1 |  27.5  81.5  160   3  1  15.1   8.3
________________________________________________________________________________

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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