Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 171245
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0645 MDT Saturday, June 17, 2017

This forecast is for Saturday, June 17, 2017:

If the trigger temperature of 75.7 F/24.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1352 ft/min (6.9 m/s)
   Maximum height of thermals.................. 21712 ft MSL (14115 ft AGL)

Forecast maximum temperature................... 89.0 F/32.1 C
Time of trigger temperature.................... 0815 MDT
Time of overdevelopment........................ 1300 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 17591 ft MSL (9994 ft AGL)
Thermal soaring outlook for Sunday 06/18....... Good

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

Remarks...

Sunrise/Sunset.................... 05:33:20 / 20:27:17 MDT
Total possible sunshine........... 14 hr 53 min 57 sec (893 min 57 sec)
Altitude of sun at 13:00:18 MDT... 74.41 degrees

Upper air data from numerical model forecast valid on 06/17/2017 at 0600 MDT

Freezing level.................. 16691 ft MSL (9094 ft AGL)
Convective condensation level... 19676 ft MSL (12079 ft AGL)
Lifted condensation level....... 20452 ft MSL (12855 ft AGL)
Lifted index.................... -3.4
K index......................... +13.2

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  -67.4 -89.3   275   16    8  -1.9  -1.1      M     M       M      M    M
 45000  -67.3 -89.1   275   20   10   6.6   3.6      M     M       M      M    M
 40000  -56.6 -69.9   290   20   10   8.7   4.8      M     M       M      M    M
 38000  -51.4 -60.5   290   19   10   8.7   4.8      M     M       M      M    M
 36000  -46.1 -51.0   285   18    9   8.7   4.8      M     M       M      M    M
 34000  -40.9 -41.6   285   19   10   8.7   4.8      M     M       M      M    M
 32000  -35.7 -32.3   280   20   10   8.7   4.8      M     M       M      M    M
 30000  -30.8 -23.4   280   19   10   8.0   4.4   37.4  99.3     4.5      M    M
 29000  -28.5 -19.3   280   19   10   8.0   4.4   36.8  98.2     4.0      M    M
 28000  -26.1 -15.0   280   18   10   7.9   4.3   36.3  97.3     3.6      M    M
 27000  -23.7 -10.7   280   18    9   7.8   4.3   35.4  95.7     3.0      M    M
 26000  -21.4  -6.5   280   17    9   7.8   4.3   34.6  94.3     2.4      M    M
 25000  -19.1  -2.4   280   16    8   7.8   4.3   34.0  93.2     1.9      M    M
 24000  -16.7   1.9   280   16    8   8.0   4.4   33.3  92.0     1.3      M    M
 23000  -13.8   7.2   280   14    7   8.0   4.4   32.5  90.5     0.6      M    M
 22000  -11.4  11.5   285   14    7   7.9   4.3   32.0  89.6     0.1      M    M
 21000   -9.1  15.6   280   12    6   7.7   4.2   31.2  88.2    -0.6   1272  6.5
 20000   -6.8  19.8   280   11    6   7.7   4.2   30.5  86.9    -1.2   1174  6.0
 19500   -5.7  21.7   280   11    6   7.7   4.2   30.2  86.4    -1.5   1125  5.7
 19000   -4.5  23.9   285   11    6   7.4   4.1   29.8  85.7    -1.8   1077  5.5
 18500   -3.4  25.9   285   11    6   7.4   4.1   29.5  85.0    -2.2   1028  5.2
 18000   -2.3  27.9   290   12    6   6.8   3.7   29.1  84.3    -2.6    980  5.0
 17500   -1.4  29.5   290   13    7   6.3   3.4   28.5  83.2    -3.2    939  4.8
 17000   -0.5  31.1   290   14    7   6.2   3.4   27.9  82.2    -3.8    897  4.6
 16500    0.5  32.9   290   15    8   7.9   4.3   27.5  81.4    -4.2    852  4.3
 16000    1.6  34.9   290   15    8   7.7   4.2   27.1  80.8    -4.6    803  4.1
 15500    2.7  36.9   290   15    8   7.9   4.3   26.8  80.2    -4.9    755  3.8
 15000    3.9  39.0   290   16    8   8.0   4.4   26.5  79.7    -5.3    706  3.6
 14500    5.0  41.0   290   16    8   8.1   4.5   26.2  79.2    -5.7    657  3.3
 14000    6.2  43.2   290   17    9   8.4   4.6   26.0  78.7    -6.0    607  3.1
 13500    7.4  45.3   290   18    9   8.5   4.7   25.8  78.4    -6.3    557  2.8
 13000    8.8  47.8   290   17    9  10.0   5.5   25.8  78.4    -6.4    500  2.5
 12500   10.0  50.0   290   17    9   8.4   4.6   25.6  78.1    -6.6    447  2.3
 12000   11.3  52.3   295   17    9   8.1   4.4   25.4  77.7    -6.9    395  2.0
 11750   11.9  53.4   295   17    9   8.6   4.7   25.3  77.5    -7.0    370  1.9
 11500   12.6  54.7   295   17    9   9.9   5.4   25.2  77.4    -7.1    342  1.7
 11250   13.3  55.9   295   17    9   9.2   5.1   25.2  77.4    -7.1    312  1.6
 11000   13.9  57.0   295   16    8   8.2   4.5   25.1  77.2    -7.2    285  1.5
 10750   14.6  58.3   300   15    8   7.6   4.2   25.0  77.0    -7.3    260  1.3
 10500   15.2  59.4   300   14    7  10.0   5.5   24.9  76.8    -7.5    234  1.2
 10250   16.0  60.8   300   13    7  11.1   6.1   25.0  77.0    -7.4    201  1.0
 10000   16.7  62.1   300   12    6   8.1   4.5   25.0  76.9    -7.4    173  0.9
  9750   17.3  63.1   300   11    6   7.7   4.2   24.8  76.7    -7.6    148  0.8
  9500   17.8  64.0   305   11    5   7.6   4.2   24.7  76.4    -7.8    124  0.6
  9250   18.4  65.1   310   10    5   8.3   4.5   24.5  76.1    -8.0    100  0.5
  9000   19.1  66.4   310    9    5   7.8   4.3   24.4  75.9    -8.1     73  0.4
  8750   19.5  67.1   310    9    5   5.8   3.2   24.2  75.5    -8.4     51  0.3
  8500   20.0  68.0   310    9    4   8.9   4.9   23.9  75.1    -8.6     29  0.1
  8250   20.5  68.9   310    8    4  -1.3  -0.7   23.7  74.7    -8.9      7  0.0
  8000   19.5  67.1   305    8    4 -25.6 -14.0   21.9  71.5   -10.7     31  0.2
  7750   17.0  62.6   300    6    3 -35.6 -19.5   18.7  65.7   -13.9     96  0.5
  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 * * * * * *

           06/17/2017 at 0900 MDT          |       06/17/2017 at 1200 MDT
                                           |
CAPE...   +61.4    LI...       +2.0        | CAPE...  +393.9    LI...       +0.6
CINH...  -108.2    K Index... +15.0        | CINH...   -10.5    K Index... +19.2
                                           |
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 -66.8 -88.2  290  17  9  -1.9  -1.0 | -66.9 -88.4  305  20 10  -1.4  -0.8
 45000 -67.1 -88.8  290  23 12   5.8   3.2 | -66.5 -87.7  305  31 16   5.4   3.0
 40000 -57.4 -71.3  305  22 11   8.5   4.7 | -57.9 -72.2  300  25 13   9.5   5.2
 38000 -52.3 -62.1  295  20 10   8.6   4.7 | -52.3 -62.1  295  23 12   9.4   5.2
 36000 -47.1 -52.8  285  18  9   8.6   4.7 | -46.6 -51.9  285  21 11   9.5   5.2
 34000 -41.9 -43.4  280  19 10   8.6   4.7 | -40.9 -41.6  285  22 11   8.2   4.5
 32000 -36.7 -34.1  280  20 10   8.6   4.7 | -36.0 -32.8  285  22 11   8.1   4.5
 30000 -31.8 -25.2  275  20 10   8.0   4.4 | -31.2 -24.2  285  21 11   8.1   4.5
 29000 -29.4 -20.9  275  20 10   8.0   4.4 | -28.8 -19.8  285  21 11   8.1   4.5
 28000 -27.0 -16.6  275  19 10   8.0   4.4 | -26.4 -15.5  285  20 10   8.0   4.4
 27000 -24.6 -12.3  275  19 10   7.9   4.3 | -24.0 -11.2  285  20 10   8.0   4.4
 26000 -22.3  -8.1  275  18  9   7.9   4.3 | -21.6  -6.9  285  20 10   8.0   4.4
 25000 -19.4  -2.9  270  18  9   8.0   4.4 | -19.2  -2.6  280  20 10   8.0   4.4
 24000 -16.9   1.6  270  18  9   8.1   4.5 | -16.9   1.6  280  20 10   7.8   4.3
 23000 -14.5   5.9  270  17  9   8.2   4.5 | -14.6   5.7  280  20 10   7.8   4.3
 22000 -12.1  10.2  270  17  9   8.3   4.5 | -12.4   9.7  275  19 10   7.8   4.3
 21000  -9.6  14.7  275  16  8   8.4   4.6 | -10.1  13.8  275  19 10   7.6   4.2
 20000  -7.1  19.2  275  16  8   8.4   4.6 |  -7.2  19.0  275  19 10   7.6   4.2
 19500  -5.9  21.4  275  16  8   8.4   4.6 |  -6.1  21.0  275  19 10   7.4   4.1
 19000  -4.7  23.5  280  16  8   7.6   4.2 |  -5.1  22.8  275  20 10   6.0   3.3
 18500  -3.5  25.7  285  17  9   7.7   4.2 |  -4.2  24.4  280  20 10   6.1   3.4
 18000  -2.4  27.7  285  17  9   8.0   4.4 |  -3.3  26.1  280  21 11   6.5   3.6
 17500  -1.2  29.8  290  17  9   8.3   4.6 |  -2.3  27.9  280  21 11   6.7   3.7
 17000   0.0  32.0  290  18  9   8.4   4.6 |  -1.3  29.7  280  21 11   6.8   3.7
 16500   1.2  34.2  290  17  9   7.6   4.2 |  -0.3  31.5  280  21 11   7.6   4.2
 16000   2.3  36.1  290  17  9   7.7   4.2 |   0.8  33.4  275  21 11   7.5   4.1
 15500   3.4  38.1  290  17  9   7.6   4.1 |   1.9  35.4  275  20 10   8.8   4.9
 15000   4.5  40.1  290  17  9   7.5   4.1 |   3.2  37.8  275  17  9   9.0   5.0
 14500   5.6  42.1  295  17  9   7.6   4.2 |   4.4  39.9  275  15  8   9.4   5.2
 14000   6.7  44.1  295  17  9   7.7   4.2 |   5.9  42.6  270  13  7   9.8   5.4
 13500   7.8  46.0  295  16  8   7.8   4.3 |   7.3  45.1  270  11  6  10.1   5.5
 13000   9.1  48.4  290  12  6   8.8   4.8 |   8.9  48.0  270  10  5  10.4   5.7
 12500  10.2  50.4  295  12  6   6.9   3.8 |  10.3  50.5  270  10  5   9.0   4.9
 12000  11.1  52.0  300  12  6   6.2   3.4 |  11.6  52.9  270   9  5   9.1   5.0
 11750  11.6  52.9  305  13  6   7.2   3.9 |  12.3  54.1  270   9  5   9.6   5.3
 11500  12.2  54.0  305  13  7   9.7   5.3 |  13.1  55.6  270   9  5  10.7   5.8
 11250  12.9  55.2  310  14  7   8.4   4.6 |  13.8  56.8  270   9  5   9.7   5.3
 11000  13.4  56.1  310  13  7   5.9   3.2 |  14.5  58.1  270   9  5   9.0   4.9
 10750  13.9  57.0  310  13  6   6.0   3.3 |  15.2  59.4  270   9  4   8.6   4.7
 10500  14.3  57.7  310  12  6   6.3   3.4 |  15.9  60.6  270   9  4  10.8   5.9
 10250  14.9  58.8  315  11  6   7.0   3.8 |  16.8  62.2  270   8  4  11.5   6.3
 10000  15.4  59.7  315  11  6   7.2   3.9 |  17.5  63.5  270   8  4   9.5   5.2
  9750  16.0  60.8  315  11  5   7.2   4.0 |  18.2  64.8  270   8  4   9.9   5.4
  9500  16.5  61.7  315  10  5   7.0   3.8 |  19.0  66.2  270   8  4   9.3   5.1
  9250  17.1  62.8  315  10  5   8.0   4.4 |  19.7  67.5  270   8  4  11.4   6.3
  9000  17.7  63.9  315   9  5   8.4   4.6 |  20.6  69.1  270   8  4  11.5   6.3
  8750  18.2  64.8  315   8  4   7.8   4.3 |  21.4  70.5  270   8  4   9.6   5.3
  8500  18.8  65.8  315   8  4   7.7   4.2 |  22.1  71.8  270   7  4   9.7   5.3
  8250  19.4  66.9  315   7  4   8.9   4.9 |  22.8  73.0  270   7  4  11.5   6.3
  8000  20.2  68.4  315   6  3  13.5   7.4 |  23.9  75.0  270   7  4  19.3  10.6
  7750  21.3  70.3  315   5  3  17.2   9.4 |  25.6  78.1  270   6  3  26.0  14.3
  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

           06/17/2017 at 1500 MDT          |       06/17/2017 at 1800 MDT
                                           |
CAPE...  +654.6    LI...       -0.8        | CAPE...  +981.3    LI...       -2.5
CINH...     0.0    K Index... +24.9        | CINH...   -12.2    K Index... +30.9
                                           |
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 -68.5 -91.3  305  20 10  -1.1  -0.6 | -67.7 -89.9  300  20 10  -0.8  -0.4
 45000 -67.2 -89.0  305  30 16   6.4   3.5 | -66.2 -87.2  310  29 15   5.9   3.2
 40000 -57.2 -71.0  305  26 13   8.8   4.8 | -56.9 -70.4  295  26 13   8.9   4.9
 38000 -51.9 -61.4  300  26 13   8.8   4.8 | -51.5 -60.7  295  24 12   8.9   4.9
 36000 -46.6 -51.9  295  25 13   8.8   4.8 | -46.2 -51.2  290  22 11   9.0   4.9
 34000 -40.8 -41.4  290  22 11   8.7   4.8 | -40.3 -40.5  295  23 12   8.6   4.7
 32000 -35.6 -32.1  285  19 10   8.7   4.8 | -35.2 -31.4  300  23 12   8.5   4.7
 30000 -30.8 -23.4  290  21 11   7.9   4.3 | -30.1 -22.2  300  24 12   8.4   4.6
 29000 -28.5 -19.3  290  22 11   7.9   4.3 | -27.6 -17.7  300  24 12   8.4   4.6
 28000 -26.2 -15.2  290  23 12   7.8   4.3 | -25.0 -13.0  305  25 13   7.8   4.3
 27000 -23.9 -11.0  290  23 12   7.7   4.2 | -22.8  -9.0  305  24 12   7.6   4.2
 26000 -21.6  -6.9  290  23 12   7.7   4.2 | -20.5  -4.9  305  24 12   7.6   4.2
 25000 -19.3  -2.7  290  23 12   7.7   4.2 | -18.3  -0.9  305  23 12   7.8   4.3
 24000 -17.1   1.2  285  22 11   7.6   4.2 | -16.5   2.3  300  23 12   5.6   3.1
 23000 -14.8   5.4  285  21 11   7.6   4.2 | -14.9   5.2  295  22 11   5.7   3.1
 22000 -12.6   9.3  280  20 10   7.6   4.2 | -13.3   8.1  290  22 11   5.9   3.2
 21000 -10.4  13.3  280  20 10   7.5   4.1 | -10.5  13.1  285  21 11   7.9   4.3
 20000  -7.6  18.3  280  20 10   7.5   4.1 |  -8.3  17.1  280  20 10   8.0   4.4
 19500  -6.5  20.3  280  20 10   7.5   4.1 |  -7.1  19.2  275  19 10   8.1   4.4
 19000  -5.5  22.1  280  19 10   7.2   3.9 |  -5.9  21.4  275  18  9   8.5   4.7
 18500  -4.4  24.1  275  19 10   7.2   3.9 |  -4.7  23.5  270  17  9   8.5   4.7
 18000  -3.3  26.1  275  18  9   7.8   4.3 |  -3.5  25.7  265  16  8   8.6   4.7
 17500  -2.2  28.0  275  16  8   8.1   4.5 |  -2.3  27.9  265  15  7   8.7   4.8
 17000  -1.1  30.0  275  14  7   8.4   4.6 |  -1.0  30.2  265  13  7   8.7   4.8
 16500   0.2  32.4  275  13  7   9.5   5.2 |   0.3  32.5  265  12  6   9.0   4.9
 16000   1.6  34.9  275  12  6   9.5   5.2 |   1.6  34.9  265  12  6   8.9   4.9
 15500   3.0  37.4  275  12  6   9.8   5.4 |   2.9  37.2  270  11  6   9.5   5.2
 15000   4.5  40.1  275  12  6   9.9   5.4 |   4.3  39.7  270  11  6   9.5   5.2
 14500   5.9  42.6  275  12  6   9.9   5.4 |   5.8  42.4  270  11  6   9.5   5.2
 14000   7.4  45.3  275  12  6   9.9   5.5 |   7.2  45.0  275  10  5   9.4   5.2
 13500   8.9  48.0  275  11  6  10.2   5.6 |   8.6  47.5  280  10  5   9.6   5.3
 13000  10.5  50.9  275  11  6  10.1   5.5 |  10.1  50.2  285   9  5   9.7   5.3
 12500  11.8  53.2  280  11  6   8.8   4.9 |  11.4  52.5  290   8  4   8.7   4.8
 12000  13.2  55.8  280  11  6   9.3   5.1 |  12.7  54.9  300   8  4   8.2   4.5
 11750  13.9  57.0  280  11  6  10.0   5.5 |  13.3  55.9  305   8  4   9.0   4.9
 11500  14.7  58.5  280  11  6  11.4   6.2 |  14.0  57.2  310   7  4  10.3   5.6
 11250  15.5  59.9  280  11  6   9.9   5.4 |  14.7  58.5  315   7  4   9.4   5.1
 11000  16.2  61.2  280  11  6   8.7   4.8 |  15.4  59.7  320   7  4   8.6   4.7
 10750  16.8  62.2  280  11  6   8.4   4.6 |  16.0  60.8  330   7  4   8.3   4.6
 10500  17.5  63.5  280  11  6  10.5   5.8 |  16.6  61.9  335   7  4   9.7   5.3
 10250  18.4  65.1  280  11  6  11.5   6.3 |  17.4  63.3  340   8  4  10.4   5.7
 10000  19.2  66.6  280  11  6   9.8   5.4 |  18.1  64.6  345   8  4   9.2   5.0
  9750  19.9  67.8  280  11  6   9.9   5.4 |  18.8  65.8  350   8  4   9.3   5.1
  9500  20.6  69.1  280  11  5   9.8   5.4 |  19.5  67.1  355   8  4   9.0   4.9
  9250  21.4  70.5  280  11  5  10.7   5.8 |  20.2  68.4  355   9  4  10.3   5.6
  9000  22.2  72.0  285  10  5  10.7   5.9 |  21.0  69.8  360   9  5  10.4   5.7
  8750  22.9  73.2  285  10  5  10.2   5.6 |  21.7  71.1  360   9  5   9.4   5.2
  8500  23.7  74.7  285  10  5   9.9   5.4 |  22.4  72.3  360   9  5   9.2   5.1
  8250  24.4  75.9  285  10  5  11.7   6.4 |  23.1  73.6  360   9  5  11.1   6.1
  8000  25.6  78.1  285  10  5  18.8  10.3 |  24.0  75.2  005   9  4  13.0   7.1
  7750  27.2  81.0  285   9  4  24.9  13.7 |  24.9  76.8  005   8  4  10.5   5.7
  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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