Soaring Guidance
Issued by NWS Denver/Boulder, CO

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Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1956 MDT Thursday, August 10, 2017

This forecast is for Friday, August 11, 2017:

If the trigger temperature of 73.0 F/22.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 352 ft/min (1.8 m/s)
   Maximum height of thermals.................. 12688 ft MSL (7336 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10185 ft MSL (4832 ft AGL)
Thermal soaring outlook for Saturday 08/12..... 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)................ Weak PVA
Potential height of wave....................... 14477 ft MSL (9125 ft AGL)
Wave soaring outlook for Saturday 08/12........ Poor

Remarks... A moist mid-level northwest flow will remain over northern colorado
           during the next 24 hours.

Sunrise/Sunset.................... 06:08:20 / 20:00:53 MDT
Total possible sunshine........... 13 hr 52 min 34 sec (832 min 34 sec)
Altitude of sun at 13:04:36 MDT... 65.25 degrees

Upper air data from numerical model forecast valid on 08/11/2017 at 0600 MDT

Freezing level.................. 15008 ft MSL (9656 ft AGL)
Convective condensation level... 12083 ft MSL (6731 ft AGL)
Lifted condensation level....... 12416 ft MSL (7064 ft AGL)
Lifted index.................... -4.8
K index......................... +23.4

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  -63.9 -83.0   325   44   22   1.6   0.9      M     M       M      M    M
 45000  -59.6 -75.3   275   39   20   5.7   3.2      M     M       M      M    M
 40000  -50.3 -58.5   260   46   24   7.2   3.9      M     M       M      M    M
 38000  -45.9 -50.6   255   44   23   7.2   3.9      M     M       M      M    M
 36000  -41.6 -42.9   255   43   22   7.1   3.9      M     M       M      M    M
 34000  -37.6 -35.7   260   40   21   6.7   3.7      M     M       M      M    M
 32000  -33.6 -28.5   265   37   19   6.7   3.7      M     M       M      M    M
 30000  -29.9 -21.8   275   34   17   5.9   3.3   46.7 116.1    14.8      M    M
 29000  -28.2 -18.8   285   33   17   5.9   3.3   45.3 113.5    13.9      M    M
 28000  -26.4 -15.5   290   32   17   6.1   3.3   44.0 111.1    13.0      M    M
 27000  -24.5 -12.1   305   33   17   6.2   3.4   42.5 108.4    12.0      M    M
 26000  -22.7  -8.9   315   35   18   6.2   3.4   41.1 106.0    11.1      M    M
 25000  -20.8  -5.4   325   38   20   6.2   3.4   39.9 103.8    10.2      M    M
 24000  -18.8  -1.8   325   37   19   6.6   3.6   38.6 101.5     9.3      M    M
 23000  -16.8   1.8   325   34   17   6.6   3.6   37.5  99.4     8.4      M    M
 22000  -14.9   5.2   325   31   16   6.6   3.6   36.4  97.6     7.6      M    M
 21000  -12.6   9.3   325   26   13   6.0   3.3   34.7  94.5     6.2      M    M
 20000  -10.9  12.4   320   22   11   6.1   3.3   33.4  92.1     5.1      M    M
 19500  -10.0  14.0   315   20   10   6.2   3.4   32.8  91.0     4.6      M    M
 19000   -9.1  15.6   320   21   11   6.8   3.7   32.3  90.1     4.1      M    M
 18500   -8.1  17.4   320   22   11   6.8   3.7   31.7  89.1     3.7      M    M
 18000   -7.1  19.2   325   24   12   7.7   4.2   31.3  88.3     3.2      M    M
 17500   -5.9  21.4   330   27   14   7.9   4.3   31.0  87.7     2.9      M    M
 17000   -4.8  23.4   335   30   15   8.0   4.4   30.7  87.2     2.6      M    M
 16500   -3.6  25.5   335   32   16   8.4   4.6   30.4  86.7     2.4      M    M
 16000   -2.3  27.9   335   34   17   8.4   4.6   30.2  86.3     2.2      M    M
 15500   -1.1  30.0   340   36   18   8.2   4.5   29.9  85.9     1.9      M    M
 15000    0.1  32.2   340   38   20   8.2   4.5   29.7  85.4     1.7      M    M
 14500    1.3  34.3   345   41   21   7.9   4.3   29.4  84.9     1.4      M    M
 14000    2.4  36.3   345   46   24   7.8   4.3   29.1  84.4     1.1      M    M
 13500    3.5  38.3   350   52   27   7.5   4.1   28.8  83.8     0.7      M    M
 13000    4.5  40.1   350   58   30   7.3   4.0   28.4  83.1     0.3      M    M
 12500    5.5  41.9   355   64   33   7.2   3.9   28.0  82.4    -0.2    535  2.7
 12000    6.5  43.7   355   70   36   7.0   3.8   27.5  81.5    -0.7    491  2.5
 11500    7.5  45.5   355   75   39   6.7   3.7   27.1  80.8    -1.2    447  2.3
 11000    8.3  46.9   355   66   34   6.0   3.3   26.5  79.7    -1.8    406  2.1
 10500    9.2  48.6   355   55   28   5.2   2.8   25.9  78.7    -2.4    367  1.9
 10250    9.5  49.1   355   48   25   4.3   2.4   25.5  77.9    -2.8    350  1.8
 10000    9.8  49.6   355   25   13   5.7   3.1   25.1  77.3    -3.2    332  1.7
  9750   10.2  50.4   200    9    5   6.5   3.6   24.9  76.7    -3.6    313  1.6
  9500   10.6  51.1   185   42   22   5.3   2.9   24.6  76.3    -3.9    293  1.5
  9250   10.9  51.6   180   63   32   3.3   1.8   24.1  75.5    -4.4    277  1.4
  9000   11.2  52.2   180   80   41   4.7   2.6   23.7  74.6    -4.9    263  1.3
  8750   11.5  52.7   180   87   45   6.3   3.5   23.4  74.0    -5.2    244  1.2
  8500   11.9  53.4   180   94   48   5.5   3.0   23.1  73.5    -5.6    225  1.1
  8250   12.3  54.1   180   95   49   5.0   2.8   22.7  72.9    -6.0    207  1.0
  8000   12.6  54.7   180   96   49   5.5   3.0   22.4  72.3    -6.3    188  1.0
  7750   13.0  55.4   180   97   50   5.8   3.2   22.1  71.7    -6.7    169  0.9
  7500   13.4  56.1   180   97   50   4.1   2.3   21.7  71.1    -7.1    151  0.8
  7250   13.6  56.5   180   96   50   3.2   1.7   21.2  70.2    -7.6    138  0.7
  7000   13.8  56.8   180   96   50   3.1   1.7   20.7  69.3    -8.2    124  0.6
  6750   14.0  57.2   180   96   49   2.5   1.4   20.2  68.3    -8.8    112  0.6
  6500   14.1  57.4   180   96   49   3.1   1.7   19.6  67.4    -9.3     99  0.5
  6250   14.4  57.9   180   95   49   3.4   1.9   19.2  66.5    -9.9     85  0.4
  6000   14.6  58.3   180   95   49   3.9   2.1   18.7  65.6   -10.4     71  0.4
  5750   14.9  58.8   180   91   47   2.8   1.5   18.2  64.8   -10.8     55  0.3
  5500   14.9  58.8   180   41   21  -0.8  -0.4   17.6  63.7   -11.6     46  0.2

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

           08/11/2017 at 0900 MDT          |       08/11/2017 at 1200 MDT
                                           |
CAPE...  +315.8    LI...       -1.9        | CAPE...  +909.5    LI...       -4.2
CINH...  -177.8    K Index... +23.9        | CINH...   -44.5    K Index... +23.5
                                           |
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 -63.8 -82.8  295  29 15   2.1   1.2 | -63.8 -82.8  300  29 15   2.4   1.3
 45000 -59.2 -74.6  285  39 20   5.3   2.9 | -58.7 -73.7  280  36 19   5.0   2.8
 40000 -50.5 -58.9  265  44 22   6.9   3.8 | -50.8 -59.4  265  42 22   6.9   3.8
 38000 -46.4 -51.5  265  42 22   6.9   3.8 | -46.6 -51.9  260  41 21   6.9   3.8
 36000 -42.3 -44.1  260  41 21   6.9   3.8 | -42.5 -44.5  260  40 20   7.0   3.8
 34000 -38.3 -36.9  265  38 19   6.7   3.7 | -38.6 -37.5  260  37 19   6.5   3.6
 32000 -34.2 -29.6  270  35 18   6.6   3.6 | -34.7 -30.5  260  34 17   6.4   3.5
 30000 -30.1 -22.2  280  31 16   6.1   3.4 | -30.3 -22.5  265  29 15   6.6   3.6
 29000 -28.2 -18.8  285  29 15   6.1   3.4 | -28.3 -18.9  270  27 14   6.6   3.6
 28000 -26.4 -15.5  290  27 14   6.0   3.3 | -26.3 -15.3  275  25 13   6.2   3.4
 27000 -24.6 -12.3  290  25 13   6.0   3.3 | -24.5 -12.1  270  23 12   6.2   3.4
 26000 -22.9  -9.2  290  23 12   6.0   3.3 | -22.6  -8.7  265  21 11   6.2   3.4
 25000 -21.1  -6.0  295  21 11   6.1   3.4 | -20.8  -5.4  260  20 10   6.4   3.5
 24000 -19.1  -2.4  290  19 10   6.9   3.8 | -18.8  -1.8  270  18 10   7.0   3.8
 23000 -17.0   1.4  285  18  9   6.9   3.8 | -16.7   1.9  280  18  9   7.0   3.8
 22000 -15.0   5.0  280  17  9   7.0   3.8 | -14.6   5.7  290  19 10   7.0   3.9
 21000 -12.9   8.8  290  17  9   7.0   3.9 | -12.5   9.5  295  18  9   7.1   3.9
 20000 -10.8  12.6  300  18  9   7.1   3.9 | -10.4  13.3  295  18  9   7.2   3.9
 19500  -9.8  14.4  305  19 10   7.1   3.9 |  -9.4  15.1  295  18  9   7.2   3.9
 19000  -8.8  16.2  310  19 10   6.8   3.7 |  -8.4  16.9  300  18  9   7.0   3.8
 18500  -7.8  18.0  310  20 10   6.8   3.7 |  -7.3  18.9  310  20 10   7.0   3.8
 18000  -6.8  19.8  315  20 11   7.0   3.8 |  -6.3  20.7  320  22 11   7.1   3.9
 17500  -5.8  21.6  320  21 11   7.1   3.9 |  -5.3  22.5  325  25 13   7.3   4.0
 17000  -4.2  24.4  325  23 12   7.6   4.1 |  -3.7  25.3  330  29 15   7.4   4.1
 16500  -3.1  26.4  330  25 13   7.9   4.3 |  -2.7  27.1  335  31 16   7.5   4.1
 16000  -2.0  28.4  330  26 14   8.0   4.4 |  -1.6  29.1  340  34 17   7.6   4.2
 15500  -0.8  30.6  335  29 15   8.3   4.5 |  -0.5  31.1  340  38 19   8.0   4.4
 15000   0.4  32.7  340  32 17   8.3   4.5 |   0.7  33.3  345  43 22   8.0   4.4
 14500   1.6  34.9  340  36 18   8.2   4.5 |   1.9  35.4  345  48 25   8.2   4.5
 14000   2.8  37.0  345  41 21   8.2   4.5 |   3.0  37.4  350  53 27   8.2   4.5
 13500   4.0  39.2  350  46 24   8.0   4.4 |   4.2  39.6  350  58 30   8.0   4.4
 13000   5.1  41.2  350  52 27   7.9   4.3 |   5.4  41.7  355  63 32   8.0   4.4
 12500   6.3  43.3  355  59 30   7.8   4.3 |   6.5  43.7  355  69 35   7.9   4.3
 12000   7.4  45.3  355  65 34   7.8   4.3 |   7.7  45.9  355  77 40   7.8   4.3
 11500   8.6  47.5  355  72 37   7.4   4.1 |   8.8  47.8  355  85 44   7.7   4.2
 11000   9.6  49.3  355  77 39   7.1   3.9 |   9.9  49.8  355  92 47   7.7   4.2
 10500  10.6  51.1  355  82 42   8.0   4.4 |  11.1  52.0  360  99 51   8.6   4.7
 10250  11.2  52.2  355  82 42   7.8   4.3 |  11.7  53.1  360 100 51   8.2   4.5
 10000  11.6  52.9  355  80 41   5.7   3.1 |  12.2  54.0  360 100 52   6.3   3.5
  9750  12.0  53.6  355  78 40   5.6   3.1 |  12.7  54.9  360 100 52   6.6   3.6
  9500  12.4  54.3  360  75 39   5.5   3.0 |  13.1  55.6  360 100 52   6.3   3.5
  9250  12.8  55.0  355  61 31   5.4   2.9 |  13.6  56.5  355  15  8   6.1   3.3
  9000  13.1  55.6  355  45 23   5.0   2.8 |  14.0  57.2  180  53 27   6.2   3.4
  8750  13.4  56.1  345   9  5   4.8   2.6 |  14.4  57.9  180  54 28   6.3   3.4
  8500  13.7  56.7  185  24 12   4.3   2.4 |  14.8  58.6  180  55 28   5.6   3.1
  8250  13.9  57.0  185  40 20   4.0   2.2 |  15.1  59.2  180  52 27   5.1   2.8
  8000  14.2  57.6  180  55 28   3.7   2.0 |  15.4  59.7  180  49 25   5.4   3.0
  7750  14.3  57.7  180  63 32   2.0   1.1 |  15.8  60.4  180  46 24   5.7   3.1
  7500  14.3  57.7  180  64 33   0.2   0.1 |  16.1  61.0  180  38 19   6.0   3.3
  7250  14.3  57.7  180  63 33  -0.4  -0.2 |  16.4  61.5  175  24 12   6.0   3.3
  7000  14.2  57.6  180  63 32   0.0   0.0 |  16.8  62.2  170  10  5   6.7   3.7
  6750  14.2  57.6  180  62 32   3.2   1.8 |  17.3  63.1  030   3  2   9.3   5.1
  6500  14.5  58.1  180  18  9   5.0   2.7 |  18.0  64.4  015   6  3  10.2   5.6
  6250  14.8  58.6  360  33 17   5.0   2.7 |  18.7  65.7  010   8  4  10.7   5.9
  6000  15.1  59.2  360  85 44   2.8   1.5 |  19.5  67.1  010  10  5   7.2   3.9
  5750  15.4  59.7  360 117 60   8.0   4.4 |  20.0  68.0  005  12  6  13.0   7.1
  5500  16.5  61.7  360 118 61  23.5  12.9 |  21.7  71.1  005  12  6  33.3  18.3

           08/11/2017 at 1500 MDT          |       08/11/2017 at 1800 MDT
                                           |
CAPE...  +753.3    LI...       -4.1        | CAPE...  +774.2    LI...       -4.8
CINH...   -12.8    K Index... +29.9        | CINH...    -2.7    K Index... +33.7
                                           |
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 -63.8 -82.8  260  25 13   1.8   1.0 | -63.7 -82.7  285  25 13   1.9   1.0
 45000 -59.7 -75.5  265  34 18   5.2   2.8 | -59.3 -74.7  265  35 18   4.6   2.5
 40000 -51.1 -60.0  250  42 22   7.3   4.0 | -51.7 -61.1  235  49 25   8.0   4.4
 38000 -46.7 -52.1  245  42 22   7.3   4.0 | -46.9 -52.4  230  51 26   8.0   4.4
 36000 -42.3 -44.1  245  42 22   7.3   4.0 | -42.1 -43.8  225  54 28   8.0   4.4
 34000 -38.2 -36.8  245  39 20   6.9   3.8 | -37.8 -36.0  225  52 27   7.1   3.9
 32000 -34.0 -29.2  250  36 19   6.9   3.8 | -33.6 -28.5  225  48 25   7.1   3.9
 30000 -29.5 -21.1  255  31 16   6.6   3.6 | -28.9 -20.0  240  35 18   6.9   3.8
 29000 -27.5 -17.5  260  29 15   6.7   3.6 | -26.9 -16.4  255  30 16   6.9   3.8
 28000 -25.5 -13.9  265  27 14   6.6   3.6 | -24.8 -12.6  270  28 14   6.6   3.6
 27000 -23.6 -10.5  270  25 13   6.6   3.6 | -22.9  -9.2  275  27 14   6.6   3.6
 26000 -21.6  -6.9  275  24 12   6.6   3.6 | -20.9  -5.6  280  26 14   6.6   3.6
 25000 -19.7  -3.5  285  23 12   6.4   3.5 | -18.9  -2.0  285  26 13   6.3   3.5
 24000 -17.9  -0.2  290  23 12   5.9   3.2 | -17.4   0.7  295  26 13   5.2   2.8
 23000 -16.2   2.8  290  23 12   5.9   3.2 | -15.8   3.6  300  26 14   5.2   2.9
 22000 -14.5   5.9  295  23 12   6.4   3.5 | -14.3   6.3  310  27 14   5.7   3.1
 21000 -12.4   9.7  305  23 12   7.3   4.0 | -12.3   9.9  320  32 17   7.0   3.8
 20000 -10.4  13.3  310  24 13   7.4   4.1 | -10.3  13.5  330  39 20   7.1   3.9
 19500  -9.3  15.3  315  25 13   7.5   4.1 |  -9.3  15.3  335  43 22   7.1   3.9
 19000  -8.3  17.1  320  26 13   7.5   4.1 |  -8.3  17.1  340  46 24   8.4   4.6
 18500  -7.2  19.0  320  27 14   7.6   4.1 |  -7.1  19.2  340  48 25   8.4   4.6
 18000  -6.2  20.8  325  29 15   7.7   4.2 |  -5.9  21.4  340  50 26   8.3   4.5
 17500  -4.5  23.9  330  31 16   8.0   4.4 |  -4.1  24.6  345  56 29   7.8   4.3
 17000  -3.3  26.1  335  33 17   7.9   4.4 |  -3.0  26.6  345  59 31   7.5   4.1
 16500  -2.2  28.0  335  33 17   7.9   4.4 |  -2.0  28.4  350  60 31   7.1   3.9
 16000  -1.1  30.0  335  33 17   8.0   4.4 |  -1.0  30.2  350  60 31   7.1   3.9
 15500  -0.0  32.0  335  32 16   8.2   4.5 |   0.0  32.0  350  58 30   7.3   4.0
 15000   1.1  34.0  340  30 15   8.3   4.5 |   1.0  33.8  350  56 29   7.3   4.0
 14500   2.3  36.1  340  29 15   8.2   4.5 |   2.0  35.6  350  51 26   7.1   3.9
 14000   3.4  38.1  345  29 15   8.2   4.5 |   3.0  37.4  350  37 19   7.0   3.9
 13500   4.6  40.3  345  30 15   7.9   4.4 |   4.0  39.2  345  21 11   7.2   3.9
 13000   5.7  42.3  350  36 19   7.8   4.3 |   5.0  41.0  185  35 18   7.3   4.0
 12500   6.8  44.2  355  43 22   7.6   4.2 |   6.0  42.8  180  90 46   7.8   4.3
 12000   7.9  46.2  355  64 33   7.4   4.1 |   7.2  45.0  180  80 41   8.6   4.7
 11500   8.9  48.0  360  86 44   7.7   4.2 |   8.4  47.1  180  65 33   8.8   4.9
 11000  10.1  50.2  360  39 20   8.2   4.5 |   9.8  49.6  180  61 31   9.4   5.1
 10500  11.2  52.2  175  13  7   9.0   4.9 |  11.2  52.2  180  60 31   8.2   4.5
 10250  11.9  53.4  175  20 11   9.3   5.1 |  11.7  53.1  180  59 30   8.8   4.8
 10000  12.5  54.5  175  22 11   8.5   4.6 |  12.5  54.5  180  59 30  10.7   5.9
  9750  13.1  55.6  175  23 12   8.8   4.8 |  13.2  55.8  180  59 30  10.6   5.8
  9500  13.7  56.7  175  24 12   8.4   4.6 |  14.0  57.2  180  59 30   9.0   4.9
  9250  14.2  57.6  175  23 12   8.5   4.6 |  14.6  58.3  180  59 30   7.5   4.1
  9000  14.8  58.6  175  23 12   9.7   5.3 |  15.2  59.4  180  59 30  10.0   5.5
  8750  15.6  60.1  175  22 12  10.2   5.6 |  16.0  60.8  180  59 30  11.4   6.2
  8500  16.3  61.3  175  22 11  10.3   5.6 |  16.9  62.4  180  59 30  10.6   5.8
  8250  17.0  62.6  175  22 11  10.8   5.9 |  17.6  63.7  180  59 30  10.2   5.6
  8000  17.8  64.0  175  21 11   9.9   5.5 |  18.4  65.1  180  58 30   9.9   5.5
  7750  18.4  65.1  175  20 11   9.1   5.0 |  19.1  66.4  180  58 30   9.5   5.2
  7500  19.1  66.4  175  20 10  10.2   5.6 |  19.8  67.6  180  58 30  10.1   5.6
  7250  19.9  67.8  175  19 10  11.1   6.1 |  20.6  69.1  180  58 30  10.9   6.0
  7000  20.7  69.3  175  18  9  10.0   5.5 |  21.4  70.5  180  57 30  10.0   5.5
  6750  21.4  70.5  175  18  9   9.2   5.0 |  22.1  71.8  180  57 29   8.8   4.8
  6500  22.1  71.8  175  17  9  10.2   5.6 |  22.8  73.0  180  57 29  10.2   5.6
  6250  22.9  73.2  175  16  8  11.9   6.5 |  23.6  74.5  180  56 29  11.8   6.5
  6000  23.7  74.7  175  14  7   8.4   4.6 |  24.4  75.9  180  55 28  10.2   5.6
  5750  24.4  75.9  175  14  7  14.3   7.8 |  25.2  77.4  180  55 28  11.2   6.2
  5500  26.1  79.0  175  14  7  33.4  18.3 |  26.2  79.2  180  55 28  17.1   9.4
________________________________________________________________________________

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.

CINH (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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