Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 161419
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0819 MDT Monday, October 16, 2017

This forecast is for Monday, October 16, 2017:

If the trigger temperature of 70.9 F/21.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 721 ft/min (3.7 m/s)
   Maximum height of thermals.................. 13700 ft MSL (8372 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1200 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................. 8986 ft MSL (3658 ft AGL)
Thermal soaring outlook for Tuesday 10/17...... Fair

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 NVA
Potential height of wave....................... 14931 ft MSL (9603 ft AGL)
Wave soaring outlook for Tuesday 10/17......... Poor

Remarks...

Sunrise/Sunset.................... 07:11:18 / 18:18:33 MDT
Total possible sunshine........... 11 hr 7 min 14 sec (667 min 14 sec)
Altitude of sun at 12:44:56 MDT... 40.96 degrees

Upper air data from numerical model forecast valid on 10/16/2017 at 0600 MDT

Freezing level.................. 13403 ft MSL (8075 ft AGL)
Convective condensation level... 23805 ft MSL (18477 ft AGL)
Lifted condensation level....... 20994 ft MSL (15665 ft AGL)
Lifted index.................... +5.4
K index......................... -15.3

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  -64.7 -84.5   340   70   36   0.4   0.2      M     M       M      M    M
 45000  -63.5 -82.3   340   83   43   2.9   1.6      M     M       M      M    M
 40000  -59.2 -74.6   345   95   49   3.4   1.8      M     M       M      M    M
 38000  -55.6 -68.1   340   91   47   6.2   3.4      M     M       M      M    M
 36000  -51.9 -61.4   340   86   44   6.1   3.4      M     M       M      M    M
 34000  -47.1 -52.8   340   80   41   7.8   4.3      M     M       M      M    M
 32000  -42.4 -44.3   340   73   38   7.8   4.3      M     M       M      M    M
 30000  -37.8 -36.0   340   70   36   7.6   4.2   37.7  99.9    10.0      M    M
 29000  -35.5 -31.9   340   69   35   7.6   4.2   36.9  98.4     9.5      M    M
 28000  -33.2 -27.8   345   68   35   7.6   4.2   36.2  97.2     9.1      M    M
 27000  -30.9 -23.6   345   68   35   7.7   4.2   35.3  95.6     8.5      M    M
 26000  -28.6 -19.5   345   70   36   7.7   4.2   34.5  94.1     8.0      M    M
 25000  -26.3 -15.3   345   71   36   7.7   4.2   33.8  92.9     7.5      M    M
 24000  -24.0 -11.2   345   71   37   7.7   4.2   33.1  91.5     7.0      M    M
 23000  -21.6  -6.9   345   72   37   7.7   4.2   32.3  90.1     6.4      M    M
 22000  -19.3  -2.7   350   72   37   7.8   4.3   31.6  89.0     6.0      M    M
 21000  -17.0   1.4   350   72   37   7.5   4.1   30.8  87.5     5.3      M    M
 20000  -14.8   5.4   350   71   37   7.5   4.1   30.0  86.0     4.7      M    M
 19500  -13.7   7.3   350   71   36   7.5   4.1   29.6  85.3     4.4      M    M
 19000  -12.6   9.3   350   71   36   7.1   3.9   29.3  84.7     4.1      M    M
 18500  -11.0  12.2   350   70   36   6.9   3.8   28.5  83.3     3.5      M    M
 18000  -10.0  14.0   350   70   36   6.9   3.8   28.0  82.5     3.1      M    M
 17500   -9.0  15.8   350   71   37   6.8   3.8   27.5  81.5     2.6      M    M
 17000   -8.0  17.6   350   72   37   6.9   3.8   27.0  80.7     2.2      M    M
 16500   -6.9  19.6   350   72   37   7.2   3.9   26.6  79.8     1.8      M    M
 16000   -5.8  21.6   350   73   38   7.1   3.9   26.1  79.1     1.4      M    M
 15500   -4.7  23.5   355   74   38   7.7   4.2   25.8  78.4     1.1      M    M
 15000   -3.6  25.5   355   75   38   7.7   4.2   25.4  77.7     0.8      M    M
 14500   -2.4  27.7   355   75   39   7.7   4.2   25.1  77.1     0.5      M    M
 14000   -1.3  29.7   355   75   38   7.7   4.2   24.7  76.5     0.2      M    M
 13500   -0.1  31.8   355   74   38   8.0   4.4   24.4  75.9    -0.1    696  3.5
 13000    1.1  34.0   355   72   37   8.2   4.5   24.2  75.5    -0.4    645  3.3
 12500    2.3  36.1   355   69   36   8.0   4.4   23.9  75.0    -0.6    593  3.0
 12000    3.5  38.3   355   65   33   7.6   4.2   23.6  74.4    -1.0    544  2.8
 11500    4.6  40.3   355   61   31   7.6   4.2   23.2  73.8    -1.3    495  2.5
 11000    5.7  42.3   350   55   28   7.6   4.2   22.9  73.2    -1.6    447  2.3
 10500    6.9  44.4   350   48   25   7.7   4.2   22.5  72.6    -2.0    398  2.0
 10250    7.4  45.3   350   45   23   7.9   4.3   22.4  72.3    -2.1    373  1.9
 10000    8.0  46.4   350   42   22   8.0   4.4   22.2  72.0    -2.3    348  1.8
  9750    8.6  47.5   350   40   20   8.2   4.5   22.1  71.8    -2.4    323  1.6
  9500    9.2  48.6   350   37   19   7.6   4.2   22.0  71.6    -2.5    297  1.5
  9250    9.8  49.6   350   39   20   6.4   3.5   21.7  71.1    -2.8    274  1.4
  9000   10.3  50.5   350   40   21   8.1   4.4   21.5  70.8    -3.0    252  1.3
  8750   11.0  51.8   350   34   18   9.9   5.4   21.5  70.7    -3.0    223  1.1
  8500   11.6  52.9   350   29   15   8.1   4.5   21.5  70.6    -3.1    195  1.0
  8250   12.2  54.0   350   30   16   6.9   3.8   21.3  70.3    -3.3    172  0.9
  8000   12.7  54.9   350   31   16   7.4   4.0   21.1  69.9    -3.5    149  0.8
  7750   13.2  55.8   350   25   13   6.9   3.8   20.9  69.6    -3.7    125  0.6
  7500   13.7  56.7   345   16    8   6.2   3.4   20.6  69.1    -4.0    103  0.5
  7250   14.2  57.6   345   16    8   5.9   3.3   20.3  68.6    -4.3     83  0.4
  7000   14.6  58.3   345   15    8   6.3   3.4   20.1  68.1    -4.6     62  0.3
  6750   14.9  58.8   220    6    3   0.7   0.4   19.7  67.4    -5.0     45  0.2
  6500   14.7  58.5   190   17    9  -3.9  -2.1   18.7  65.7    -6.0     44  0.2
  6250   14.5  58.1   185   28   15  -1.7  -1.0   17.7  63.9    -6.9     44  0.2
  6000   14.3  57.7   185   40   21  -5.6  -3.1   16.8  62.3    -7.9     43  0.2
  5750   13.2  55.8   185   54   28 -26.7 -14.7   15.0  59.0    -9.8     68  0.3
  5500   10.1  50.2   180   58   30 -50.7 -27.8   11.2  52.2   -13.6    153  0.8

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

           10/16/2017 at 0900 MDT          |       10/16/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...       +4.5        | CAPE...     0.0    LI...       +3.9
CINH...    -0.1    K Index... -16.8        | CINH...    -0.1    K Index... -19.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.2 -85.4  305  28 14   0.6   0.3 | -65.7 -86.3  305  26 13   0.6   0.3
 45000 -63.7 -82.7  310  34 17   3.4   1.8 | -64.0 -83.2  310  35 18   3.8   2.1
 40000 -58.6 -73.5  310  39 20   3.9   2.2 | -58.3 -72.9  310  40 21   4.6   2.5
 38000 -55.0 -67.0  310  38 20   6.1   3.4 | -54.4 -65.9  310  39 20   6.5   3.6
 36000 -50.9 -59.6  310  36 19   6.2   3.4 | -50.0 -58.0  310  37 19   6.5   3.6
 34000 -46.6 -51.9  305  34 17   7.6   4.1 | -45.9 -50.6  305  34 18   7.1   3.9
 32000 -42.1 -43.8  305  30 16   7.6   4.2 | -41.6 -42.9  305  30 16   7.1   3.9
 30000 -37.6 -35.7  300  27 14   7.6   4.1 | -37.2 -35.0  300  27 14   7.5   4.1
 29000 -35.3 -31.5  300  26 13   7.6   4.1 | -35.0 -31.0  300  25 13   7.5   4.1
 28000 -33.0 -27.4  300  24 13   7.6   4.2 | -32.7 -26.9  300  23 12   7.5   4.1
 27000 -30.8 -23.4  300  23 12   7.5   4.1 | -30.5 -22.9  300  22 11   7.4   4.1
 26000 -28.5 -19.3  300  22 11   7.5   4.1 | -28.3 -18.9  295  21 11   7.4   4.1
 25000 -26.3 -15.3  300  21 11   7.5   4.1 | -26.0 -14.8  295  19 10   7.4   4.1
 24000 -24.0 -11.2  300  20 10   7.6   4.2 | -23.8 -10.8  295  18  9   7.5   4.1
 23000 -21.7  -7.1  300  19 10   7.7   4.2 | -21.5  -6.7  295  17  9   7.5   4.1
 22000 -19.4  -2.9  300  18  9   7.7   4.2 | -19.3  -2.7  290  16  8   7.4   4.1
 21000 -17.1   1.2  305  17  9   7.7   4.2 | -17.0   1.4  295  15  8   7.6   4.2
 20000 -14.8   5.4  305  16  8   7.7   4.2 | -14.1   6.6  295  14  7   7.6   4.2
 19500 -13.6   7.5  305  16  8   7.7   4.2 | -13.0   8.6  295  13  7   7.7   4.2
 19000 -11.9  10.6  305  15  8   7.5   4.1 | -11.8  10.8  295  13  7   7.8   4.3
 18500 -10.8  12.6  310  15  8   7.5   4.1 | -10.7  12.7  295  13  7   7.8   4.3
 18000  -9.7  14.5  310  14  7   7.6   4.2 |  -9.5  14.9  295  12  6   7.9   4.4
 17500  -8.5  16.7  310  14  7   7.6   4.2 |  -8.3  17.1  300  12  6   8.0   4.4
 17000  -7.4  18.7  310  13  7   7.6   4.2 |  -7.1  19.2  300  12  6   8.0   4.4
 16500  -6.3  20.7  310  13  7   7.6   4.1 |  -5.9  21.4  300  12  6   8.1   4.4
 16000  -5.1  22.8  310  13  6   7.6   4.1 |  -4.7  23.5  300  11  6   8.1   4.4
 15500  -4.0  24.8  310  12  6   7.5   4.1 |  -3.5  25.7  305  11  6   8.2   4.5
 15000  -2.9  26.8  310  12  6   7.5   4.1 |  -2.2  28.0  305  11  6   8.1   4.5
 14500  -1.7  28.9  315  11  6   7.8   4.3 |  -1.0  30.2  305  11  6   8.1   4.5
 14000  -0.6  30.9  310  11  6   7.8   4.3 |   0.2  32.4  305  11  6   8.1   4.4
 13500   0.6  33.1  310  10  5   7.8   4.3 |   1.4  34.5  305  11  5   8.0   4.4
 13000   1.8  35.2  310  10  5   7.9   4.3 |   2.6  36.7  305  11  6   7.9   4.3
 12500   2.9  37.2  310  10  5   7.9   4.3 |   3.8  38.8  305  11  6   7.8   4.3
 12000   4.1  39.4  310  10  5   7.8   4.3 |   4.9  40.8  305  11  6   7.7   4.2
 11500   5.3  41.5  305   9  5   7.8   4.3 |   6.1  43.0  300  11  6   7.5   4.1
 11000   6.4  43.5  305   9  5   7.7   4.2 |   7.2  45.0  300  11  6   7.2   4.0
 10500   7.6  45.7  300   9  5   7.7   4.2 |   8.2  46.8  295  11  5   7.4   4.1
 10250   8.2  46.8  300   9  5   7.6   4.2 |   8.8  47.8  295  11  5   7.6   4.2
 10000   8.7  47.7  300   9  5   7.0   3.8 |   9.4  48.9  295  11  5   7.3   4.0
  9750   9.2  48.6  295   9  5   6.9   3.8 |   9.9  49.8  295  10  5   7.4   4.1
  9500   9.7  49.5  295   9  5   6.6   3.6 |  10.5  50.9  295  10  5   6.9   3.8
  9250  10.2  50.4  295   9  5   5.8   3.2 |  10.9  51.6  295  10  5   5.7   3.1
  9000  10.6  51.1  295   9  4   7.0   3.9 |  11.4  52.5  295  10  5   7.2   4.0
  8750  11.2  52.2  290   8  4   8.5   4.6 |  12.0  53.6  290  10  5   8.7   4.8
  8500  11.8  53.2  285   8  4   7.3   4.0 |  12.6  54.7  290  10  5   7.3   4.0
  8250  12.3  54.1  285   7  4   6.5   3.6 |  13.1  55.6  290   9  5   6.6   3.6
  8000  12.8  55.0  285   7  4   6.8   3.7 |  13.6  56.5  290   9  4   6.7   3.7
  7750  13.3  55.9  285   6  3   6.2   3.4 |  14.1  57.4  290   8  4   6.6   3.6
  7500  13.8  56.8  280   6  3   5.3   2.9 |  14.6  58.3  285   7  3   7.2   4.0
  7250  14.1  57.4  280   5  3   4.9   2.7 |  15.1  59.2  280   6  3   7.2   4.0
  7000  14.5  58.1  285   5  3   5.8   3.2 |  15.7  60.3  275   5  2   8.0   4.4
  6750  14.9  58.8  275   5  2   1.8   1.0 |  16.3  61.3  270   4  2   8.1   4.4
  6500  14.7  58.5  270   4  2  -2.4  -1.3 |  16.8  62.2  270   3  2   7.0   3.8
  6250  14.6  58.3  265   4  2   0.0   0.0 |  17.3  63.1  265   2  1   7.2   3.9
  6000  14.5  58.1  260   4  2  -5.6  -3.1 |  17.9  64.2  255   2  1   6.7   3.7
  5750  13.6  56.5  255   3  2 -17.7  -9.7 |  18.4  65.1  250   1  1  11.3   6.2
  5500  12.0  53.6  235   3  1 -21.8 -12.0 |  19.6  67.3  250   1  1  20.4  11.2

           10/16/2017 at 1500 MDT          |       10/16/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...       +3.7        | CAPE...     0.0    LI...       +4.1
CINH...    -0.1    K Index... -23.0        | CINH...    -0.2    K Index... -18.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.8 -86.4  300  27 14   0.8   0.4 | -65.5 -85.9  300  28 15   0.6   0.3
 45000 -63.9 -83.0  305  36 18   3.6   2.0 | -63.8 -82.8  300  35 18   3.4   1.9
 40000 -58.5 -73.3  305  42 21   4.7   2.6 | -58.8 -73.8  300  39 20   4.7   2.6
 38000 -53.7 -64.7  305  41 21   7.2   4.0 | -53.7 -64.7  300  37 19   7.7   4.2
 36000 -49.3 -56.7  305  40 20   7.2   4.0 | -49.0 -56.2  300  36 18   7.7   4.2
 34000 -45.2 -49.4  305  36 18   6.7   3.7 | -44.7 -48.5  300  34 17   7.0   3.8
 32000 -41.1 -42.0  300  31 16   6.8   3.7 | -40.5 -40.9  295  31 16   7.0   3.9
 30000 -36.8 -34.2  300  27 14   7.3   4.0 | -36.2 -33.2  295  28 14   7.3   4.0
 29000 -34.6 -30.3  295  25 13   7.3   4.0 | -34.0 -29.2  295  26 13   7.3   4.0
 28000 -32.4 -26.3  295  23 12   7.3   4.0 | -31.8 -25.2  290  24 13   7.3   4.0
 27000 -30.2 -22.4  295  22 11   7.6   4.2 | -29.6 -21.3  290  22 11   7.4   4.1
 26000 -27.9 -18.2  295  20 10   7.6   4.2 | -27.4 -17.3  290  20 10   7.4   4.1
 25000 -25.6 -14.1  290  19 10   7.6   4.2 | -25.1 -13.2  290  18  9   7.4   4.1
 24000 -23.3  -9.9  290  18  9   7.3   4.0 | -23.0  -9.4  290  17  9   7.0   3.9
 23000 -21.1  -6.0  290  17  9   7.3   4.0 | -20.8  -5.4  290  16  8   7.0   3.9
 22000 -18.9  -2.0  290  16  8   7.3   4.0 | -18.7  -1.7  290  15  8   7.0   3.9
 21000 -16.7   1.9  290  15  8   7.6   4.1 | -16.0   3.2  290  14  7   7.2   3.9
 20000 -13.9   7.0  290  14  7   7.6   4.1 | -13.9   7.0  290  14  7   7.2   3.9
 19500 -12.7   9.1  290  14  7   7.6   4.1 | -12.8   9.0  290  13  7   7.2   3.9
 19000 -11.6  11.1  290  14  7   7.7   4.2 | -11.7  10.9  290  13  7   7.6   4.1
 18500 -10.4  13.3  290  13  7   7.7   4.2 | -10.6  12.9  290  13  7   7.5   4.1
 18000  -9.2  15.4  290  13  7   7.8   4.3 |  -9.4  15.1  290  13  6   7.5   4.1
 17500  -8.1  17.4  290  13  7   7.9   4.3 |  -8.3  17.1  295  12  6   7.5   4.1
 17000  -6.9  19.6  290  13  7   7.9   4.3 |  -7.2  19.0  295  12  6   7.5   4.1
 16500  -5.7  21.7  290  13  7   7.8   4.3 |  -6.1  21.0  295  12  6   7.6   4.2
 16000  -4.5  23.9  295  13  6   7.8   4.3 |  -4.9  23.2  295  12  6   7.6   4.2
 15500  -3.4  25.9  295  12  6   7.8   4.3 |  -3.8  25.2  295  12  6   7.8   4.3
 15000  -2.2  28.0  295  12  6   7.8   4.3 |  -2.6  27.3  295  12  6   7.8   4.3
 14500  -1.0  30.2  295  12  6   7.8   4.3 |  -1.4  29.5  295  12  6   7.8   4.3
 14000   0.1  32.2  295  12  6   7.8   4.3 |  -0.3  31.5  290  11  6   7.8   4.3
 13500   1.3  34.3  295  12  6   7.9   4.3 |   0.9  33.6  290  11  6   7.9   4.3
 13000   2.5  36.5  295  11  6   8.0   4.4 |   2.1  35.8  290  11  6   8.0   4.4
 12500   3.7  38.7  295  11  6   8.1   4.5 |   3.3  37.9  290  11  6   8.1   4.5
 12000   4.9  40.8  295  11  6   8.4   4.6 |   4.5  40.1  290  10  5   8.3   4.6
 11500   6.2  43.2  295  11  6   8.3   4.6 |   5.7  42.3  290  10  5   8.5   4.6
 11000   7.4  45.3  295  11  5   8.2   4.5 |   7.0  44.6  290  10  5   8.8   4.8
 10500   8.6  47.5  295  10  5   8.8   4.8 |   8.3  46.9  290  10  5   9.5   5.2
 10250   9.3  48.7  295  10  5   9.0   4.9 |   9.1  48.4  295   9  5   9.9   5.4
 10000   9.9  49.8  295  10  5   7.8   4.3 |   9.8  49.6  295   9  5   8.8   4.8
  9750  10.5  50.9  295   9  5   7.6   4.2 |  10.4  50.7  295   9  5   8.5   4.7
  9500  11.0  51.8  295   9  5   7.6   4.2 |  11.0  51.8  295   9  4   8.6   4.7
  9250  11.6  52.9  295   9  4   7.3   4.0 |  11.7  53.1  295   8  4   8.6   4.7
  9000  12.2  54.0  295   8  4   8.8   4.8 |  12.3  54.1  295   8  4   9.3   5.1
  8750  12.9  55.2  295   7  4   9.2   5.1 |  13.1  55.6  295   8  4   9.9   5.4
  8500  13.6  56.5  295   7  3  11.4   6.2 |  13.8  56.8  300   7  4   9.7   5.3
  8250  14.3  57.7  295   6  3   2.5   1.4 |  14.5  58.1  300   7  4   9.8   5.4
  8000  15.0  59.0  300   5  3  36.0  19.8 |  15.2  59.4  305   6  3   9.2   5.1
  7750  18.7  65.7  305   4  2  30.1  16.5 |  15.9  60.6  305   6  3   8.2   4.5
  7500  18.7  65.7  305   4  2  -8.0  -4.4 |  16.5  61.7  310   6  3   8.9   4.9
  7250  18.7  65.7  305   4  2   2.5   1.4 |  17.2  63.0  315   5  3   9.7   5.3
  7000  18.7  65.7  305   4  2  -1.4  -0.8 |  17.9  64.2  320   5  2   9.1   5.0
  6750  18.7  65.7  305   4  2   3.8   2.1 |  18.5  65.3  320   4  2   7.8   4.3
  6500  19.3  66.7  305   4  2   9.7   5.3 |  19.1  66.4  325   4  2   8.0   4.4
  6250  20.1  68.2  310   4  2  10.7   5.9 |  19.7  67.5  330   4  2   8.1   4.5
  6000  20.8  69.4  310   4  2   7.6   4.1 |  20.4  68.7  340   3  2   9.7   5.3
  5750  21.6  70.9  310   4  2   9.4   5.2 |  20.9  69.6  355   3  2   0.4   0.2
  5500  22.7  72.9  310   3  2  21.5  11.8 |  20.1  68.2  360   2  1 -19.5 -10.7
________________________________________________________________________________

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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