Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 111309
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0709 MDT Friday, August 11, 2017

This forecast is for Friday, August 11, 2017:

If the trigger temperature of 74.5 F/23.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 183 ft/min (0.9 m/s)
   Maximum height of thermals.................. 10892 ft MSL (5607 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ 1400 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................. 9270 ft MSL (3984 ft AGL)
Thermal soaring outlook for Saturday 08/12..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 42623 ft MSL (37338 ft AGL)
Wave soaring outlook for Saturday 08/12........ Good

Remarks...

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 rawinsonde observation taken on 08/11/2017 at 0600 MDT

Freezing level.................. 14943 ft MSL (9658 ft AGL)
Convective condensation level... 13037 ft MSL (7752 ft AGL)
Lifted condensation level....... 12625 ft MSL (7340 ft AGL)
Lifted index.................... -2.1
K index......................... +20.5

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  -66.9 -88.4   275   62   32   1.0   0.5   81.4 178.6    31.9      M    M
 45000  -58.8 -73.8   270   69   36   1.9   1.0   70.4 158.8    27.3      M    M
 40000  -50.2 -58.4   275   89   46   6.2   3.4   60.1 140.1    22.4      M    M
 38000  -46.5 -51.7   270   90   46   6.2   3.4   57.1 134.8    20.9      M    M
 36000  -42.7 -44.9   275   83   43   6.0   3.3   54.0 129.2    19.3      M    M
 34000  -37.8 -36.0   270   80   41   8.5   4.7   52.7 126.8    18.8      M    M
 32000  -34.4 -29.9   275   76   39   3.5   1.9   49.4 121.0    16.9      M    M
 30000  -31.2 -24.2   270   68   35   6.3   3.5   46.0 114.8    14.7      M    M
 29000  -29.3 -20.7   270   65   33   6.3   3.5   44.5 112.1    13.7      M    M
 28000  -26.9 -16.4   270   60   31   6.3   3.5   42.8 109.0    12.6      M    M
 27000  -25.0 -13.0   275   56   29   6.2   3.4   41.6 106.8    11.8      M    M
 26000  -22.7  -8.9   275   52   27   8.5   4.7   40.8 105.5    11.3      M    M
 25000  -20.2  -4.4   275   49   25   8.5   4.7   40.4 104.8    11.1      M    M
 24000  -17.7   0.1   275   47   24   8.3   4.6   39.9 103.8    10.8      M    M
 23000  -15.1   4.8   275   46   23   7.6   4.2   39.4 103.0    10.5      M    M
 22000  -13.9   7.0   275   44   22  -0.4  -0.2   37.5  99.5     8.9      M    M
 21000  -14.4   6.1   275   42   22   5.7   3.1   33.6  92.5     5.5      M    M
 20000  -12.2  10.0   275   40   21   7.2   4.0   32.7  90.9     4.8      M    M
 19500  -11.2  11.8   275   35   18   7.2   3.9   32.2  90.0     4.5      M    M
 19000   -9.9  14.2   275   33   17   8.9   4.9   31.9  89.5     4.3      M    M
 18500   -8.6  16.5   275   32   16   8.3   4.6   31.8  89.2     4.1      M    M
 18000   -7.5  18.5   280   31   16   8.1   4.4   31.5  88.7     3.9      M    M
 17500   -6.3  20.7   280   30   16   8.0   4.4   31.2  88.2     3.6      M    M
 17000   -5.1  22.8   280   30   15   8.1   4.4   31.0  87.7     3.4      M    M
 16500   -3.9  25.0   285   29   15   8.1   4.4   30.7  87.3     3.2      M    M
 16000   -2.8  27.0   285   28   14   8.1   4.4   30.5  87.0     3.0      M    M
 15500   -1.6  29.1   285   28   14   8.1   4.4   30.2  86.4     2.7      M    M
 15000   -0.4  31.3   290   28   14   8.1   4.4   30.0  85.9     2.5      M    M
 14500    0.8  33.4   290   28   14   8.1   4.5   29.7  85.5     2.2      M    M
 14000    2.5  36.5   295   28   14   8.1   4.5   29.4  84.8     1.8      M    M
 13500    3.7  38.7   295   27   14   8.2   4.5   29.1  84.3     1.6      M    M
 13000    4.9  40.8   295   26   13   8.2   4.5   28.8  83.9     1.3      M    M
 12500    6.1  43.0   295   21   11   8.2   4.5   28.5  83.3     1.0      M    M
 12000    7.3  45.1   290   16    8   8.2   4.5   28.2  82.8     0.7      M    M
 11500    8.4  47.1   290   13    7   8.2   4.5   27.9  82.3     0.3      M    M
 11000    9.6  49.3   295    9    5   8.1   4.4   27.7  81.8     0.0      M    M
 10500   10.6  51.1   300    6    3   5.4   2.9   27.3  81.1    -0.4    342  1.7
 10250   10.9  51.6   305    5    2   4.3   2.4   26.8  80.3    -0.8    325  1.7
 10000   11.2  52.2   305    4    2   4.5   2.5   26.4  79.6    -1.3    309  1.6
  9750   11.5  52.7   265    3    1   4.9   2.7   26.0  78.8    -1.7    292  1.5
  9500   11.8  53.2   225    3    2   0.3   0.2   25.5  78.0    -2.2    278  1.4
  9250   11.5  52.7   205    5    3  -3.4  -1.9   24.6  76.2    -3.2    279  1.4
  9000   11.2  52.2   195    7    4  -2.0  -1.1   23.6  74.5    -4.2    280  1.4
  8750   10.9  51.6   195    9    5  -3.5  -1.9   22.6  72.8    -5.3    281  1.4
  8500   10.7  51.3   200   11    6   1.5   0.8   21.7  71.1    -6.3    281  1.4
  8250   11.1  52.0   200   13    7   8.3   4.6   21.4  70.6    -6.6    262  1.3
  8000   11.7  53.1   200   15    8   8.3   4.6   21.3  70.4    -6.7    236  1.2
  7750   12.3  54.1   205   14    7   8.4   4.6   21.2  70.2    -6.9    210  1.1
  7500   12.9  55.2   205   12    6   8.1   4.4   21.1  70.0    -7.0    185  0.9
  7250   13.5  56.3   210   11    6   9.5   5.2   21.0  69.8    -7.2    159  0.8
  7000   14.1  57.4   215   10    5   4.1   2.3   20.9  69.6    -7.3    134  0.7
  6750   14.1  57.4   215    9    4  -2.5  -1.3   20.1  68.2    -8.1    128  0.7
  6500   13.9  57.0   220    7    4  -1.9  -1.0   19.2  66.5    -9.0    126  0.6
  6250   13.7  56.7   225    6    3  -2.0  -1.1   18.3  64.9   -10.0    124  0.6
  6000   13.5  56.3   230    4    2  -2.0  -1.1   17.4  63.4   -10.9    122  0.6
  5750   13.4  56.1   210    2    1  -2.0  -1.1   16.5  61.8   -11.8    120  0.6
  5500   13.2  55.8   155    2    1  -2.0  -1.1   15.7  60.2   -12.7    118  0.6

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

           08/11/2017 at 0900 MDT          |       08/11/2017 at 1200 MDT
                                           |
CAPE...   +85.4    LI...       -1.9        | CAPE...  +567.1    LI...       -3.6
CINH...  -261.6    K Index... +24.5        | CINH...   -68.3    K Index... +24.5
                                           |
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 -63.7 -82.7  275  25 13   2.0   1.1 | -63.9 -83.0  270  24 12   2.3   1.3
 45000 -59.0 -74.2  270  36 19   5.6   3.1 | -58.5 -73.3  270  34 18   5.6   3.1
 40000 -50.0 -58.0  270  43 22   6.5   3.6 | -49.9 -57.8  265  40 21   6.5   3.6
 38000 -46.1 -51.0  270  42 22   6.5   3.6 | -46.0 -50.8  265  40 20   6.5   3.6
 36000 -42.2 -44.0  270  41 21   6.5   3.6 | -42.1 -43.8  265  39 20   6.5   3.6
 34000 -38.1 -36.6  270  39 20   6.8   3.7 | -38.0 -36.4  265  37 19   6.8   3.8
 32000 -34.1 -29.4  270  37 19   6.7   3.7 | -33.9 -29.0  265  35 18   6.7   3.7
 30000 -29.7 -21.5  270  33 17   6.4   3.5 | -29.6 -21.3  265  32 16   6.4   3.5
 29000 -27.8 -18.0  270  30 16   6.4   3.5 | -27.7 -17.9  265  30 15   6.4   3.5
 28000 -25.9 -14.6  270  28 14   5.9   3.2 | -25.8 -14.4  270  28 15   5.9   3.2
 27000 -24.3 -11.7  270  26 13   5.7   3.1 | -24.1 -11.4  270  26 14   5.8   3.2
 26000 -22.6  -8.7  270  24 12   5.7   3.1 | -22.3  -8.1  270  24 12   5.8   3.2
 25000 -20.9  -5.6  270  22 11   5.8   3.2 | -20.6  -5.1  270  22 11   5.9   3.2
 24000 -19.0  -2.2  270  20 10   6.3   3.5 | -18.7  -1.7  270  21 11   6.6   3.6
 23000 -17.2   1.0  275  19 10   6.3   3.5 | -16.8   1.8  270  20 10   6.6   3.6
 22000 -15.3   4.5  275  18  9   6.4   3.5 | -14.8   5.4  275  19 10   6.7   3.7
 21000 -13.3   8.1  275  17  9   6.7   3.7 | -12.8   9.0  275  18  9   6.9   3.8
 20000 -11.4  11.5  275  16  8   6.7   3.7 | -10.8  12.6  275  17  9   6.9   3.8
 19500 -10.4  13.3  275  16  8   6.6   3.6 |  -9.8  14.4  275  16  8   6.9   3.8
 19000  -9.4  15.1  280  15  8   7.7   4.2 |  -8.8  16.2  280  16  8   7.3   4.0
 18500  -8.2  17.2  280  15  8   7.7   4.2 |  -7.8  18.0  280  16  8   7.3   4.0
 18000  -7.1  19.2  280  15  8   7.7   4.2 |  -6.7  19.9  280  15  8   7.3   4.0
 17500  -6.0  21.2  280  14  7   7.8   4.3 |  -5.1  22.8  280  14  7   7.4   4.1
 17000  -4.3  24.3  285  14  7   8.0   4.4 |  -4.0  24.8  285  14  7   7.5   4.1
 16500  -3.1  26.4  285  13  7   8.1   4.4 |  -2.9  26.8  285  13  7   7.6   4.2
 16000  -2.0  28.4  285  13  7   8.1   4.5 |  -1.8  28.8  285  13  7   7.6   4.2
 15500  -0.8  30.6  290  12  6   8.3   4.5 |  -0.7  30.7  285  12  6   8.0   4.4
 15000   0.4  32.7  290  12  6   8.3   4.5 |   0.5  32.9  290  11  6   7.9   4.3
 14500   1.6  34.9  290  11  6   8.3   4.6 |   1.7  35.1  290  11  5   8.2   4.5
 14000   2.9  37.2  290  10  5   8.3   4.6 |   2.9  37.2  290  10  5   8.2   4.5
 13500   4.1  39.4  295  10  5   8.0   4.4 |   4.1  39.4  295   9  5   8.0   4.4
 13000   5.2  41.4  295   9  5   7.8   4.3 |   5.2  41.4  295   8  4   7.8   4.3
 12500   6.3  43.3  295   8  4   7.5   4.1 |   6.3  43.3  300   7  4   7.7   4.2
 12000   7.4  45.3  295   7  4   7.2   4.0 |   7.5  45.5  300   7  3   7.6   4.2
 11500   8.4  47.1  300   6  3   6.9   3.8 |   8.6  47.5  300   6  3   7.4   4.1
 11000   9.3  48.7  295   5  3   6.5   3.6 |   9.6  49.3  305   5  3   7.3   4.0
 10500  10.2  50.4  295   4  2   7.5   4.1 |  10.7  51.3  305   4  2   8.2   4.5
 10250  10.8  51.4  295   4  2   7.2   4.0 |  11.3  52.3  305   4  2   7.5   4.1
 10000  11.2  52.2  290   4  2   4.4   2.4 |  11.7  53.1  305   4  2   5.3   2.9
  9750  11.4  52.5  285   3  2   4.0   2.2 |  12.1  53.8  305   3  2   5.3   2.9
  9500  11.7  53.1  280   3  1   4.1   2.2 |  12.4  54.3  305   3  2   5.3   2.9
  9250  11.9  53.4  280   3  1   4.2   2.3 |  12.8  55.0  305   3  1   5.5   3.0
  9000  12.2  54.0  275   2  1   3.8   2.1 |  13.1  55.6  305   2  1   4.6   2.5
  8750  12.4  54.3  260   2  1   3.3   1.8 |  13.4  56.1  305   2  1   3.9   2.1
  8500  12.6  54.7  240   2  1   3.3   1.8 |  13.6  56.5  310   1  1   3.9   2.1
  8250  12.8  55.0  240   2  1   3.3   1.8 |  13.8  56.8  340   1  0   3.7   2.0
  8000  13.0  55.4  230   1  1   3.0   1.7 |  14.0  57.2  015   1  1   3.9   2.1
  7750  13.1  55.6  215   1  1   2.0   1.1 |  14.2  57.6  035   1  1   4.7   2.6
  7500  13.2  55.8  210   1  1   1.1   0.6 |  14.6  58.3  040   1  1   6.4   3.5
  7250  13.3  55.9  225   1  0   1.0   0.5 |  15.0  59.0  035   2  1   7.0   3.8
  7000  13.3  55.9  000   0  0   0.7   0.4 |  15.4  59.7  035   2  1   7.4   4.1
  6750  13.3  55.9  000   0  0   2.2   1.2 |  16.0  60.8  040   2  1   9.9   5.4
  6500  13.6  56.5  000   0  0   3.6   2.0 |  16.8  62.2  040   2  1  10.5   5.8
  6250  13.8  56.8  000   0  0   4.8   2.6 |  17.6  63.7  040   2  1  10.7   5.9
  6000  14.1  57.4  085   1  0  -0.0  -0.0 |  18.3  64.9  035   2  1   8.3   4.5
  5750  14.0  57.2  020   1  0   4.2   2.3 |  19.0  66.2  025   2  1  13.8   7.6
  5500  15.0  59.0  025   1  0  25.4  13.9 |  20.6  69.1  025   2  1  30.6  16.8

           08/11/2017 at 1500 MDT          |       08/11/2017 at 1800 MDT
                                           |
CAPE...  +692.1    LI...       -4.3        | CAPE...  +767.5    LI...       -4.5
CINH...   -18.4    K Index... +28.3        | CINH...    -6.6    K Index... +33.3
                                           |
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 -64.1 -83.4  270  25 13   1.9   1.0 | -63.9 -83.0  270  25 13   1.6   0.9
 45000 -59.2 -74.6  265  34 17   5.6   3.1 | -59.3 -74.7  265  34 18   5.4   3.0
 40000 -50.6 -59.1  265  39 20   7.0   3.8 | -50.9 -59.6  260  39 20   7.1   3.9
 38000 -46.4 -51.5  265  38 19   6.9   3.8 | -46.7 -52.1  260  38 20   7.1   3.9
 36000 -42.2 -44.0  260  37 19   6.9   3.8 | -42.4 -44.3  260  37 19   7.1   3.9
 34000 -37.9 -36.2  260  35 18   7.2   3.9 | -38.3 -36.9  260  34 18   6.9   3.8
 32000 -33.7 -28.7  260  32 17   7.0   3.9 | -34.1 -29.4  260  32 16   6.8   3.7
 30000 -29.0 -20.2  260  30 15   6.9   3.8 | -29.4 -20.9  260  29 15   7.2   3.9
 29000 -26.9 -16.4  260  29 15   6.9   3.8 | -27.2 -17.0  260  28 15   7.2   3.9
 28000 -24.9 -12.8  265  27 14   6.3   3.4 | -25.2 -13.4  260  27 14   6.7   3.6
 27000 -23.0  -9.4  265  26 13   6.2   3.4 | -23.2  -9.8  265  26 14   6.6   3.6
 26000 -21.2  -6.2  270  25 13   6.2   3.4 | -21.2  -6.2  265  25 13   6.6   3.6
 25000 -19.3  -2.7  270  24 12   6.2   3.4 | -19.3  -2.7  270  24 13   6.5   3.6
 24000 -17.5   0.5  275  23 12   6.2   3.4 | -17.5   0.5  270  23 12   6.1   3.3
 23000 -15.7   3.7  275  22 11   6.2   3.4 | -15.7   3.7  275  21 11   6.1   3.3
 22000 -13.9   7.0  275  21 11   6.2   3.4 | -14.0   6.8  280  19 10   6.3   3.4
 21000 -12.1  10.2  275  21 11   6.2   3.4 | -12.0  10.4  280  18  9   6.7   3.7
 20000 -10.3  13.5  275  20 10   6.3   3.5 | -10.1  13.8  285  16  8   6.7   3.7
 19500  -9.4  15.1  280  20 10   6.2   3.4 |  -9.1  15.6  285  16  8   6.7   3.7
 19000  -8.4  16.9  280  19 10   7.3   4.0 |  -8.1  17.4  285  15  8   7.2   4.0
 18500  -7.4  18.7  280  18  9   7.3   4.0 |  -7.1  19.2  285  14  7   7.2   3.9
 18000  -6.3  20.7  280  17  9   7.5   4.1 |  -6.1  21.0  290  14  7   7.2   4.0
 17500  -5.2  22.6  280  17  9   7.8   4.3 |  -5.0  23.0  290  13  7   7.2   3.9
 17000  -3.6  25.5  280  15  8   7.9   4.3 |  -3.4  25.9  290  13  7   7.3   4.0
 16500  -2.4  27.7  280  14  7   7.9   4.3 |  -2.4  27.7  290  12  6   7.5   4.1
 16000  -1.3  29.7  280  13  7   7.9   4.3 |  -1.3  29.7  290  11  6   7.5   4.1
 15500  -0.2  31.6  280  12  6   7.7   4.2 |  -0.2  31.6  290  10  5   7.7   4.2
 15000   0.9  33.6  280  11  6   7.7   4.2 |   0.9  33.6  290   9  5   7.7   4.2
 14500   2.1  35.8  280  10  5   8.1   4.5 |   2.0  35.6  285   8  4   7.6   4.2
 14000   3.2  37.8  280   9  5   8.2   4.5 |   3.1  37.6  280   7  4   7.6   4.2
 13500   4.4  39.9  280   8  4   8.0   4.4 |   4.1  39.4  275   6  3   7.5   4.1
 13000   5.6  42.1  275   7  3   7.9   4.3 |   5.2  41.4  265   5  2   7.5   4.1
 12500   6.8  44.2  275   6  3   7.5   4.1 |   6.3  43.3  245   4  2   7.4   4.1
 12000   7.8  46.0  275   4  2   7.1   3.9 |   7.3  45.1  225   3  2   7.4   4.0
 11500   8.8  47.8  270   3  2   7.0   3.8 |   8.3  46.9  200   3  1   7.7   4.2
 11000   9.8  49.6  260   2  1   6.9   3.8 |   9.5  49.1  185   3  1   8.6   4.7
 10500  10.8  51.4  205   1  0   8.0   4.4 |  10.7  51.3  175   3  1  10.3   5.6
 10250  11.5  52.7  140   1  0   8.2   4.5 |  11.5  52.7  165   3  1  10.1   5.5
 10000  11.9  53.4  130   1  1   6.8   3.7 |  12.1  53.8  165   3  2   7.7   4.2
  9750  12.4  54.3  125   1  1   7.3   4.0 |  12.7  54.9  165   3  2   8.2   4.5
  9500  12.9  55.2  120   2  1   6.8   3.7 |  13.3  55.9  165   3  2   8.8   4.8
  9250  13.3  55.9  110   2  1   6.8   3.7 |  14.0  57.2  165   3  2   9.7   5.3
  9000  13.8  56.8  105   2  1   9.0   4.9 |  14.7  58.5  165   3  2   9.5   5.2
  8750  14.5  58.1  110   2  1  10.4   5.7 |  15.4  59.7  165   3  2   9.0   5.9
  8500  15.2  59.4  110   2  1   9.6   5.3 |  16.0  60.8  165   4  2  10.0   5.5
  8250  15.9  60.6  100   2  1   9.2   5.1 |  16.9  62.4  165   4  2  11.6   6.3
  8000  16.5  61.7  095   2  1   9.4   5.2 |  17.7  63.9  165   3  2   9.8   5.4
  7750  17.2  63.0  100   2  1   9.6   5.3 |  18.3  64.9  165   4  2   7.9   4.3
  7500  17.9  64.2  100   2  1  10.1   5.5 |  18.9  66.0  160   4  2   9.8   5.4
  7250  18.7  65.7  095   2  1  10.5   5.8 |  19.8  67.6  160   4  2  11.6   6.4
  7000  19.5  67.1  090   2  1   9.9   5.4 |  20.6  69.1  165   4  2   9.9   5.4
  6750  20.2  68.4  090   2  1   9.6   5.3 |  21.2  70.2  160   4  2   7.8   4.3
  6500  20.9  69.6  090   2  1  10.3   5.7 |  21.8  71.2  160   4  2   9.9   5.4
  6250  21.7  71.1  090   2  1  11.2   6.1 |  22.7  72.9  160   4  2  12.4   6.8
  6000  22.5  72.5  085   2  1   9.4   5.1 |  23.5  74.3  160   3  2   9.4   5.1
  5750  23.3  73.9  090   2  1  15.0   8.2 |  24.2  75.6  160   3  2  10.2   5.6
  5500  24.9  76.8  085   2  1  29.2  16.0 |  25.2  77.4  160   3  2  19.2  10.5
________________________________________________________________________________

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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