Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 171325
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0625 MST Friday, November 17, 2017

This forecast is for Friday, November 17, 2017:

If the trigger temperature of 61.3 F/16.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 245 ft/min (1.2 m/s)
   Maximum height of thermals.................. 12656 ft MSL (5039 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 0945 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 10388 ft MSL (2771 ft AGL)
Thermal soaring outlook for Saturday 11/18..... Poor

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:44:56 / 16:43:43 MST
Total possible sunshine........... 9 hr 58 min 47 sec (598 min 47 sec)
Altitude of sun at 11:44:19 MST... 31.74 degrees

Upper air data from numerical model forecast valid on 11/17/2017 at 0500 MST

Freezing level.................. 13346 ft MSL (5729 ft AGL)
Convective condensation level... 18783 ft MSL (11166 ft AGL)
Lifted condensation level....... 16766 ft MSL (9148 ft AGL)
Lifted index.................... +2.9
K index......................... +7.8

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  -68.1 -90.6   255   41   21   5.4   3.0      M     M       M      M    M
 45000  -60.3 -76.5   255   43   22   2.7   1.5      M     M       M      M    M
 40000  -55.9 -68.6   260   60   31   2.6   1.4      M     M       M      M    M
 38000  -53.1 -63.6   260   59   31   5.1   2.8      M     M       M      M    M
 36000  -50.0 -58.0   265   57   30   5.2   2.8      M     M       M      M    M
 34000  -46.2 -51.2   270   56   29   7.8   4.3      M     M       M      M    M
 32000  -41.5 -42.7   270   55   28   7.8   4.3      M     M       M      M    M
 30000  -36.9 -34.4   270   52   27   7.5   4.1   32.0  89.7    11.5      M    M
 29000  -34.6 -30.3   270   49   25   7.5   4.1   31.1  88.0    10.9      M    M
 28000  -32.4 -26.3   270   46   24   7.5   4.1   30.3  86.5    10.3      M    M
 27000  -30.2 -22.4   270   43   22   7.1   3.9   29.5  85.1     9.8      M    M
 26000  -28.0 -18.4   270   40   21   7.1   3.9   28.4  83.2     9.1      M    M
 25000  -25.4 -13.7   265   37   19   7.1   3.9   27.3  81.1     8.2      M    M
 24000  -23.2  -9.8   265   35   18   7.9   4.3   26.4  79.6     7.6      M    M
 23000  -20.8  -5.4   265   34   18   7.8   4.3   25.7  78.2     7.1      M    M
 22000  -18.5  -1.3   265   34   18   7.8   4.3   25.0  77.1     6.6      M    M
 21000  -16.2   2.8   265   34   18   8.0   4.4   24.4  75.9     6.1      M    M
 20000  -13.8   7.2   265   34   17   8.0   4.4   23.7  74.7     5.5      M    M
 19500  -12.6   9.3   270   34   17   8.0   4.4   23.5  74.2     5.3      M    M
 19000  -11.4  11.5   270   33   17   8.2   4.5   23.2  73.7     5.1      M    M
 18500  -10.3  13.5   270   33   17   6.1   3.3   22.8  73.0     4.7      M    M
 18000   -9.4  15.1   270   34   17   6.1   3.4   22.2  71.9     4.2      M    M
 17500   -8.5  16.7   270   34   17   6.4   3.5   21.6  70.8     3.7      M    M
 17000   -7.5  18.5   270   33   17   6.8   3.7   21.1  69.9     3.2      M    M
 16500   -6.5  20.3   265   31   16   6.9   3.8   20.6  69.0     2.8      M    M
 16000   -5.5  22.1   265   30   16   6.2   3.4   20.0  68.1     2.3      M    M
 15500   -4.6  23.7   265   30   15   6.3   3.5   19.5  67.1     1.8      M    M
 15000   -3.7  25.3   265   30   15   6.8   3.8   18.9  66.1     1.3      M    M
 14500   -2.6  27.3   265   29   15   7.1   3.9   18.5  65.3     0.8      M    M
 14000   -1.6  29.1   270   29   15   7.4   4.0   18.1  64.5     0.4      M    M
 13500   -0.4  31.3   265   26   13   8.1   4.4   17.7  63.9     0.1      M    M
 13000    0.7  33.3   260   23   12  12.2   6.7   17.4  63.4    -0.2    497  2.5
 12500    2.3  36.1   260   20   10   5.2   2.9   17.5  63.6    -0.1    435  2.2
 12000    3.2  37.8   250   16    8   6.5   3.6   17.0  62.7    -0.6    392  2.0
 11750    3.8  38.8   245   15    7   8.3   4.5   16.8  62.3    -0.8    368  1.9
 11500    4.4  39.9   245   14    7   6.5   3.6   16.7  62.1    -1.0    343  1.7
 11250    4.7  40.5   245   15    8   4.1   2.3   16.3  61.4    -1.4    325  1.7
 11000    5.0  41.0   245   15    8   4.7   2.6   15.9  60.6    -1.7    308  1.6
 10750    5.4  41.7   245   15    8   4.0   2.2   15.5  59.9    -2.2    291  1.5
 10500    5.6  42.1   250   17    9   3.6   2.0   15.0  59.0    -2.6    275  1.4
 10250    5.9  42.6   250   18    9   3.5   1.9   14.5  58.2    -3.1    260  1.3
 10000    6.1  43.0   255   20   10   3.4   1.8   14.1  57.3    -3.6    246  1.2
  9750    6.3  43.3   255   21   11   3.0   1.6   13.6  56.4    -4.2    232  1.2
  9500    6.5  43.7   260   23   12   3.0   1.6   13.0  55.4    -4.7    219  1.1
  9250    6.7  44.1   260   25   13   2.2   1.2   12.5  54.5    -5.3    206  1.0
  9000    6.8  44.2   260   27   14   0.4   0.2   11.8  53.3    -6.0    197  1.0
  8750    6.7  44.1   260   27   14  -0.1  -0.0   11.1  52.0    -6.7    190  1.0
  8500    6.7  44.1   260   26   13  -0.2  -0.1   10.3  50.6    -7.5    184  0.9
  8250    6.6  43.9   260   25   13   0.3   0.2    9.6  49.3    -8.3    178  0.9
  8000    6.7  44.1   260   23   12   1.3   0.7    8.9  48.1    -9.0    170  0.9
  7750    6.8  44.2   260   18    9   0.8   0.4    8.3  46.9    -9.7    160  0.8
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           11/17/2017 at 0800 MST          |       11/17/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +2.6        | CAPE...     0.0    LI...       +1.2
CINH...     0.0    K Index...  +8.4        | CINH...     0.0    K Index... +12.5
                                           |
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 -67.2 -89.0  260  41 21   4.9   2.7 | -65.5 -85.9  260  41 21   4.6   2.5
 45000 -60.1 -76.2  255  43 22   1.6   0.9 | -58.7 -73.7  255  44 23   2.1   1.2
 40000 -57.2 -71.0  260  53 27   1.7   0.9 | -55.7 -68.3  260  61 31   2.1   1.2
 38000 -53.7 -64.7  260  56 29   6.9   3.8 | -52.8 -63.0  260  63 33   5.9   3.2
 36000 -49.6 -57.3  265  59 31   6.9   3.8 | -49.3 -56.7  260  65 33   5.9   3.2
 34000 -45.2 -49.4  265  61 31   7.8   4.3 | -45.5 -49.9  260  65 33   7.4   4.1
 32000 -40.5 -40.9  265  60 31   7.8   4.3 | -40.5 -40.9  260  63 33   7.5   4.1
 30000 -36.2 -33.2  265  58 30   6.1   3.4 | -36.4 -33.5  265  60 31   5.5   3.0
 29000 -34.4 -29.9  265  54 28   6.1   3.4 | -34.8 -30.6  265  58 30   5.5   3.0
 28000 -32.5 -26.5  265  51 26   6.1   3.4 | -33.1 -27.6  265  55 28   5.5   3.0
 27000 -30.7 -23.3  265  48 25   6.6   3.6 | -31.4 -24.5  265  52 27   6.6   3.6
 26000 -28.7 -19.7  265  46 24   6.7   3.7 | -29.4 -20.9  265  49 25   6.8   3.7
 25000 -26.2 -15.2  265  43 22   6.7   3.7 | -27.4 -17.3  265  47 24   6.8   3.7
 24000 -24.1 -11.4  265  40 21   7.2   4.0 | -25.3 -13.5  265  45 23   6.5   3.6
 23000 -22.0  -7.6  260  39 20   7.2   4.0 | -23.5 -10.3  265  42 22   6.1   3.4
 22000 -19.8  -3.6  260  38 19   7.2   4.0 | -21.7  -7.1  265  39 20   6.2   3.4
 21000 -17.6   0.3  260  35 18   7.7   4.2 | -19.9  -3.8  265  37 19   7.6   4.1
 20000 -15.4   4.3  265  32 16   7.6   4.2 | -17.4   0.7  265  34 17   8.3   4.5
 19500 -14.2   6.4  265  30 15   7.6   4.2 | -16.2   2.8  265  33 17   8.3   4.5
 19000 -13.1   8.4  265  28 15   7.7   4.2 | -14.4   6.1  265  31 16   8.2   4.5
 18500 -12.0  10.4  270  27 14   7.3   4.0 | -13.1   8.4  265  27 14   9.6   5.3
 18000 -10.9  12.4  270  27 14   7.3   4.0 | -11.6  11.1  250  20 10   9.7   5.3
 17500  -9.8  14.4  270  28 14   7.5   4.1 | -10.2  13.6  230  15  8   9.3   5.1
 17000  -8.6  16.5  270  27 14   8.1   4.4 |  -8.9  16.0  225  14  7   8.5   4.6
 16500  -7.4  18.7  270  25 13   8.2   4.5 |  -7.7  18.1  230  13  7   8.6   4.7
 16000  -6.3  20.7  270  25 13   6.9   3.8 |  -6.5  20.3  235  12  6   7.4   4.0
 15500  -5.3  22.5  270  24 12   7.0   3.8 |  -5.4  22.3  240  12  6   7.4   4.1
 15000  -4.3  24.3  270  23 12   7.4   4.1 |  -4.4  24.1  245  12  6   6.7   3.7
 14500  -3.1  26.4  270  22 12   7.7   4.2 |  -3.4  25.9  250  12  6   6.3   3.4
 14000  -2.0  28.4  270  21 11   7.4   4.0 |  -2.5  27.5  255  12  6   6.1   3.3
 13500  -1.0  30.2  265  20 10   6.8   3.7 |  -1.7  28.9  260  14  7   5.9   3.2
 13000  -0.0  32.0  260  19 10   9.1   5.0 |  -0.9  30.4  265  16  8   8.5   4.7
 12500   1.0  33.8  265  18  9   3.3   1.8 |   0.2  32.4  265  18  9   4.3   2.3
 12000   1.7  35.1  265  20 10   4.1   2.3 |   1.0  33.8  270  21 11   4.9   2.7
 11750   2.0  35.6  265  20 10   6.2   3.4 |   1.4  34.5  270  23 12   7.1   3.9
 11500   2.5  36.5  270  20 10   6.1   3.4 |   1.9  35.4  270  24 13   6.2   3.4
 11250   2.9  37.2  270  20 10   4.6   2.5 |   2.3  36.1  270  26 13   3.9   2.1
 11000   3.2  37.8  270  21 11   5.0   2.7 |   2.6  36.7  270  27 14   4.7   2.6
 10750   3.6  38.5  270  21 11   5.5   3.0 |   2.9  37.2  270  29 15   3.4   1.8
 10500   4.0  39.2  270  22 11   6.1   3.4 |   3.1  37.6  270  29 15   2.7   1.5
 10250   4.5  40.1  270  23 12   6.0   3.3 |   3.3  37.9  270  30 15   4.2   2.3
 10000   4.9  40.8  270  23 12   6.1   3.4 |   3.6  38.5  265  29 15   4.7   2.6
  9750   5.3  41.5  265  23 12   5.4   3.0 |   3.9  39.0  265  28 14   6.1   3.4
  9500   5.7  42.3  265  24 12   5.1   2.8 |   4.5  40.1  265  26 14   7.1   3.9
  9250   6.0  42.8  265  25 13   4.7   2.6 |   5.0  41.0  265  25 13   7.9   4.3
  9000   6.3  43.3  265  25 13   3.4   1.9 |   5.6  42.1  260  23 12   9.9   5.4
  8750   6.4  43.5  260  25 13   1.8   1.0 |   6.4  43.5  260  22 11  10.2   5.6
  8500   6.5  43.7  260  24 12   1.2   0.6 |   7.1  44.8  260  21 11  10.5   5.8
  8250   6.6  43.9  260  23 12   1.3   0.7 |   7.9  46.2  260  20 10   9.8   5.4
  8000   6.7  44.1  255  21 11   3.8   2.1 |   8.7  47.7  260  18  9  12.7   7.0
  7750   7.2  45.0  255  16  8   8.5   4.6 |   9.9  49.8  260  15  8  21.1  11.6
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/17/2017 at 1400 MST          |       11/17/2017 at 1700 MST
                                           |
CAPE...   +53.1    LI...       -0.8        | CAPE...    +5.9    LI...       -0.3
CINH...   -35.1    K Index...  +9.3        | CINH...  -101.4    K Index...  +1.4
                                           |
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 -65.3 -85.5  260  43 22   4.6   2.5 | -64.6 -84.3  260  41 21   4.4   2.4
 45000 -58.6 -73.5  260  46 24   1.6   0.9 | -58.2 -72.8  260  48 25   2.1   1.1
 40000 -55.7 -68.3  260  65 33   1.9   1.1 | -55.0 -67.0  260  64 33   2.1   1.2
 38000 -52.5 -62.5  260  70 36   6.2   3.4 | -52.6 -62.7  260  69 36   5.4   3.0
 36000 -48.8 -55.8  260  73 38   6.2   3.4 | -49.0 -56.2  260  74 38   5.4   3.0
 34000 -45.0 -49.0  260  73 38   6.6   3.6 | -45.5 -49.9  260  76 39   6.5   3.6
 32000 -41.1 -42.0  260  68 35   6.6   3.6 | -41.6 -42.9  265  72 37   6.5   3.6
 30000 -37.2 -35.0  260  63 32   6.3   3.5 | -37.9 -36.2  265  68 35   5.2   2.9
 29000 -35.3 -31.5  260  61 31   6.3   3.5 | -36.3 -33.3  265  64 33   5.3   2.9
 28000 -33.4 -28.1  260  59 31   6.3   3.5 | -34.7 -30.5  265  59 31   5.3   2.9
 27000 -31.5 -24.7  260  58 30   6.4   3.5 | -33.2 -27.8  265  55 28   5.2   2.9
 26000 -29.6 -21.3  260  55 28   6.5   3.5 | -31.6 -24.9  265  51 26   5.0   2.8
 25000 -27.6 -17.7  265  52 27   6.5   3.5 | -30.1 -22.2  270  46 24   5.0   2.8
 24000 -25.7 -14.3  265  50 26   6.6   3.6 | -28.6 -19.5  270  42 22   4.8   2.7
 23000 -23.8 -10.8  265  45 23   4.9   2.7 | -26.7 -16.1  270  39 20   7.0   3.8
 22000 -22.3  -8.1  265  41 21   4.9   2.7 | -24.1 -11.4  275  36 18   7.0   3.8
 21000 -20.8  -5.4  270  37 19   6.5   3.5 | -22.0  -7.6  275  33 17   7.1   3.9
 20000 -18.8  -1.8  270  33 17   6.8   3.7 | -19.8  -3.6  275  31 16   7.1   3.9
 19500 -17.8  -0.0  270  31 16   6.8   3.7 | -18.8  -1.8  275  30 15   7.1   3.9
 19000 -16.8   1.8  270  30 15   6.9   3.8 | -17.7   0.1  275  29 15   7.2   3.9
 18500 -15.8   3.6  270  28 14   8.1   4.5 | -16.7   1.9  275  28 14   7.7   4.2
 18000 -14.4   6.1  270  26 13   9.1   5.0 | -15.4   4.3  275  27 14   8.3   4.6
 17500 -13.1   8.4  270  24 12   9.2   5.0 | -14.2   6.4  275  27 14   8.3   4.6
 17000 -11.8  10.8  270  22 11   8.3   4.5 | -12.9   8.8  275  27 14   8.9   4.9
 16500 -10.5  13.1  270  21 11   8.4   4.6 | -11.6  11.1  275  27 14   8.9   4.9
 16000  -9.3  15.3  270  20 10   8.3   4.6 | -10.3  13.5  275  27 14   9.3   5.1
 15500  -8.1  17.4  270  19 10   8.3   4.5 |  -8.9  16.0  270  22 12   9.5   5.2
 15000  -6.9  19.6  270  19 10   8.1   4.5 |  -7.5  18.5  265  18  9   9.4   5.1
 14500  -5.7  21.7  265  18  9   7.9   4.3 |  -6.2  20.8  265  16  8   9.1   5.0
 14000  -4.5  23.9  265  18  9   8.0   4.4 |  -4.9  23.2  265  14  7   9.1   5.0
 13500  -3.3  26.1  265  18  9   8.6   4.7 |  -3.6  25.5  265  14  7   8.5   4.7
 13000  -2.0  28.4  265  19 10   5.3   2.9 |  -2.3  27.9  265  15  8   6.8   3.7
 12500  -1.4  29.5  270  20 10   6.6   3.6 |  -1.6  29.1  270  18  9   5.2   2.8
 12000  -0.5  31.1  270  22 11   5.9   3.3 |  -0.8  30.6  270  21 11   5.4   3.0
 11750  -0.1  31.8  270  22 12   6.4   3.5 |  -0.4  31.3  270  22 12   7.5   4.1
 11500   0.3  32.5  270  22 11   7.0   3.9 |   0.2  32.4  270  23 12   7.5   4.1
 11250   0.8  33.4  270  21 11   7.1   3.9 |   0.7  33.3  265  24 13   5.6   3.1
 11000   1.3  34.3  265  21 11   6.7   3.7 |   1.1  34.0  265  25 13   6.3   3.4
 10750   1.8  35.2  265  20 11   8.4   4.6 |   1.5  34.7  265  26 13   5.6   3.1
 10500   2.5  36.5  265  20 10  10.3   5.7 |   1.9  35.4  265  26 13   5.1   2.8
 10250   3.3  37.9  265  20 10   9.9   5.4 |   2.3  36.1  260  24 13   6.5   3.6
 10000   4.0  39.2  265  19 10   9.7   5.3 |   2.8  37.0  260  23 12   7.1   3.9
  9750   4.7  40.5  265  19 10  10.1   5.5 |   3.2  37.8  260  22 11   7.9   4.4
  9500   5.5  41.9  265  19 10  10.4   5.7 |   3.9  39.0  260  21 11   9.5   5.2
  9250   6.3  43.3  265  18  9  10.5   5.8 |   4.6  40.3  260  20 10   9.4   5.1
  9000   7.1  44.8  265  18  9  11.0   6.0 |   5.3  41.5  255  19 10   9.2   5.1
  8750   7.9  46.2  265  18  9  10.6   5.8 |   6.0  42.8  255  17  9   9.2   5.0
  8500   8.7  47.7  265  17  9  10.3   5.6 |   6.6  43.9  255  16  8   9.1   5.0
  8250   9.4  48.9  265  17  9   9.9   5.5 |   7.3  45.1  255  16  8   9.2   5.1
  8000  10.2  50.4  265  16  8  10.7   5.9 |   8.0  46.4  255  14  7   8.0   4.4
  7750  11.1  52.0  265  14  7  16.7   9.2 |   8.4  47.1  255  12  6   4.2   2.3
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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