Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 311346
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0746 MDT Friday, July 31, 2015

This forecast is for Friday, July 31, 2015:

If the trigger temperature of 74.3 F/23.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 314 ft/min (1.6 m/s)
   Maximum height of thermals.................. 13032 ft MSL (5863 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9832 ft MSL (2663 ft AGL)
Thermal soaring outlook for Saturday 08/01..... Good

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

Remarks...

Sunrise/Sunset.................... 05:58:50 / 20:12:14 MDT
Total possible sunshine........... 14 hr 13 min 24 sec (853 min 24 sec)
Altitude of sun at 13:05:19 MDT... 69.23 degrees

Upper air data from numerical model forecast valid on 07/31/2015 at 0600 MDT

Freezing level.................. 15906 ft MSL (8737 ft AGL)
Convective condensation level... 14817 ft MSL (7648 ft AGL)
Lifted condensation level....... 14643 ft MSL (7474 ft AGL)
Lifted index.................... -0.7
K index......................... +14.3

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  -67.1 -88.8   270   26   14   2.2   1.2      M     M       M      M    M
 45000  -61.2 -78.2   260   40   21   6.4   3.5      M     M       M      M    M
 40000  -51.3 -60.3   260   45   23   7.6   4.2      M     M       M      M    M
 38000  -46.8 -52.2   265   41   21   7.6   4.2      M     M       M      M    M
 36000  -42.2 -44.0   275   37   19   8.0   4.4      M     M       M      M    M
 34000  -37.3 -35.1   275   33   17   8.2   4.5      M     M       M      M    M
 32000  -32.3 -26.1   275   29   15   9.0   4.9      M     M       M      M    M
 30000  -27.5 -17.5   275   27   14   8.1   4.4   43.4 110.1    14.2      M    M
 29000  -25.1 -13.2   280   26   13   8.1   4.4   42.8 109.0    13.8      M    M
 28000  -22.3  -8.1   280   23   12   6.6   3.6   41.8 107.3    13.3      M    M
 27000  -20.3  -4.5   285   19   10   6.6   3.6   40.6 105.0    12.4      M    M
 26000  -18.3  -0.9   290   15    8   6.6   3.6   39.5 103.0    11.7      M    M
 25000  -16.2   2.8   300   12    6   6.4   3.5   38.4 101.1    11.0      M    M
 24000  -14.3   6.3   300   10    5   6.4   3.5   37.1  98.8    10.0      M    M
 23000  -12.4   9.7   295    9    4   6.5   3.5   36.0  96.7     9.2      M    M
 22000  -10.5  13.1   295    7    4   4.4   2.4   34.7  94.5     8.2      M    M
 21000   -9.3  15.3   315    8    4   4.4   2.4   32.7  90.9     6.6      M    M
 20000   -8.0  17.6   335    9    5   4.5   2.5   30.9  87.6     5.0      M    M
 19500   -7.4  18.7   340   10    5   5.6   3.1   30.1  86.1     4.3      M    M
 19000   -6.3  20.7   345   12    6   7.0   3.9   29.6  85.2     3.8      M    M
 18500   -5.3  22.5   345   13    7   7.3   4.0   29.1  84.4     3.4      M    M
 18000   -4.4  24.1   350   14    7   6.4   3.5   28.6  83.5     2.9      M    M
 17500   -3.4  25.9   355   12    6   6.5   3.6   28.1  82.5     2.4      M    M
 17000   -2.5  27.5   360   10    5   6.9   3.8   27.5  81.6     1.9      M    M
 16500   -1.4  29.5   015    7    4   7.2   3.9   27.1  80.8     1.5      M    M
 16000   -0.3  31.5   050    5    2   7.2   4.0   26.7  80.0     1.1      M    M
 15500    0.9  33.6   075    6    3   8.1   4.4   26.4  79.4     0.9      M    M
 15000    2.1  35.8   080    7    4   7.9   4.4   26.1  78.9     0.6      M    M
 14500    3.4  38.1   085    8    4   9.1   5.0   25.9  78.6     0.5      M    M
 14000    4.7  40.5   085    9    4   9.2   5.0   25.8  78.4     0.4      M    M
 13500    6.1  43.0   085    9    5   8.8   4.8   25.7  78.2     0.3      M    M
 13000    7.3  45.1   090    9    5   8.6   4.7   25.5  77.9     0.0      M    M
 12500    8.6  47.5   095    9    5   6.7   3.7   25.3  77.6    -0.2    468  2.4
 12000    9.5  49.1   100    8    4   9.4   5.2   24.9  76.9    -0.7    425  2.2
 11750   10.1  50.2   100    8    4   9.1   5.0   24.9  76.8    -0.8    399  2.0
 11500   10.8  51.4   105    8    4   8.4   4.6   24.8  76.7    -1.0    373  1.9
 11250   11.2  52.2   105    7    4   7.2   3.9   24.7  76.4    -1.2    352  1.8
 11000   11.7  53.1   110    7    3   7.3   4.0   24.5  76.0    -1.5    330  1.7
 10750   12.2  54.0   115    6    3   7.5   4.1   24.3  75.7    -1.8    309  1.6
 10500   12.6  54.7   120    5    3   7.1   3.9   24.1  75.4    -2.0    287  1.5
 10250   13.5  56.3   140    3    2   6.7   3.7   23.6  74.5    -2.7    247  1.3
 10000   13.9  57.0   165    3    1   7.6   4.2   23.4  74.1    -3.0    227  1.2
  9750   14.4  57.9   205    2    1   7.7   4.2   23.3  73.9    -3.2    204  1.0
  9500   15.0  59.0   220    2    1   7.1   3.9   23.1  73.5    -3.4    180  0.9
  9250   15.5  59.9   235    3    1   7.2   4.0   22.9  73.2    -3.6    157  0.8
  9000   16.0  60.8   245    3    1   7.0   3.8   22.7  72.8    -3.8    133  0.7
  8750   16.4  61.5   250    3    2   4.5   2.5   22.4  72.3    -4.1    114  0.6
  8500   16.6  61.9   250    3    2   2.7   1.5   21.9  71.4    -4.7    101  0.5
  8250   16.8  62.2   255    4    2   3.6   2.0   21.4  70.5    -5.2     88  0.4
  8000   17.0  62.6   255    4    2   2.0   1.1   20.9  69.6    -5.8     75  0.4
  7750   16.7  62.1   260    4    2  -8.1  -4.5   20.0  68.0    -6.8     75  0.4
  7500   15.6  60.1   260    4    2 -20.3 -11.2   18.2  64.7    -8.7    102  0.5
  7250   14.5  58.1   265    3    2   0.0   0.0   16.3  61.4   -10.5    128  0.6
  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 * * * * * *

           07/31/2015 at 0900 MDT          |       07/31/2015 at 1200 MDT
                                           |
K index... +16.1  LI... +269.4             | K index... +19.0  LI... +269.1
CAPE... +441.3  CIN... -43.0               | CAPE... +883.7  CIN... -2.4
                                           |
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 -66.3 -87.3  270  25 13   1.8   1.0 | -67.1 -88.8  265  26 13   2.1   1.2
 45000 -61.1 -78.0  270  37 19   6.3   3.4 | -61.4 -78.5  270  36 18   6.5   3.6
 40000 -51.5 -60.7  275  40 21   7.1   3.9 | -51.3 -60.3  275  38 20   7.6   4.2
 38000 -47.2 -53.0  275  40 20   7.1   3.9 | -46.8 -52.2  275  38 20   7.6   4.2
 36000 -42.3 -44.1  280  38 20   8.7   4.8 | -41.6 -42.9  275  38 19   8.2   4.5
 34000 -37.2 -35.0  280  33 17   8.6   4.7 | -36.7 -34.1  275  34 17   8.1   4.5
 32000 -32.0 -25.6  275  27 14   9.0   5.0 | -31.9 -25.4  275  30 15   8.9   4.9
 30000 -27.3 -17.1  275  24 13   7.9   4.3 | -27.0 -16.6  275  24 13   8.2   4.5
 29000 -25.0 -13.0  275  23 12   7.9   4.4 | -24.6 -12.3  275  22 11   8.2   4.5
 28000 -22.7  -8.9  280  21 11   6.5   3.6 | -22.3  -8.1  275  19 10   7.0   3.8
 27000 -20.8  -5.4  280  18  9   6.7   3.6 | -20.2  -4.4  280  17  9   7.1   3.9
 26000 -18.8  -1.8  285  15  8   6.7   3.7 | -18.1  -0.6  280  16  8   7.1   3.9
 25000 -16.8   1.8  290  12  6   6.7   3.7 | -16.0   3.2  285  14  7   7.0   3.8
 24000 -14.8   5.4  285  11  6   6.7   3.7 | -13.9   7.0  285  12  6   7.0   3.8
 23000 -12.3   9.9  270  11  6   6.7   3.7 | -11.2  11.8  280  11  6   7.0   3.9
 22000 -10.5  13.1  270  10  5   3.5   1.9 |  -9.4  15.1  280  10  5   3.8   2.1
 21000  -9.4  15.1  295   9  5   3.8   2.1 |  -8.2  17.2  290  10  5   4.2   2.3
 20000  -8.3  17.1  320  10  5   3.8   2.1 |  -7.0  19.4  300  11  6   4.3   2.4
 19500  -7.7  18.1  330  11  6   5.7   3.1 |  -6.4  20.5  305  11  6   4.7   2.6
 19000  -6.7  19.9  335  12  6   6.8   3.7 |  -5.7  21.7  315  11  6   4.9   2.7
 18500  -5.7  21.7  340  13  7   7.0   3.8 |  -5.0  23.0  325  10  5   4.8   2.7
 18000  -4.8  23.4  350  12  6   6.4   3.5 |  -4.3  24.3  335  10  5   6.0   3.3
 17500  -3.8  25.2  355  10  5   6.5   3.6 |  -3.4  25.9  340   8  4   5.9   3.2
 17000  -2.8  27.0  005   8  4   7.4   4.0 |  -2.5  27.5  355   7  4   6.8   3.8
 16500  -1.6  29.1  015   5  3   7.8   4.3 |  -1.4  29.5  360   6  3   7.4   4.1
 16000  -0.4  31.3  040   3  1   7.9   4.3 |  -0.2  31.6  010   5  2   7.4   4.1
 15500   0.8  33.4  070   4  2   7.8   4.3 |   0.9  33.6  025   4  2   7.1   3.9
 15000   2.0  35.6  075   6  3   7.7   4.2 |   2.0  35.6  045   5  3   7.0   3.9
 14500   3.3  37.9  080   8  4   8.6   4.7 |   3.1  37.6  055   5  3   7.8   4.3
 14000   4.6  40.3  085   8  4   8.6   4.7 |   4.3  39.7  060   6  3   7.8   4.3
 13500   5.8  42.4  085   8  4   8.6   4.7 |   5.5  41.9  065   6  3   8.0   4.4
 13000   7.0  44.6  090   8  4   8.7   4.8 |   6.6  43.9  065   6  3   8.1   4.4
 12500   8.2  46.8  090   8  4   6.3   3.5 |   7.7  45.9  065   6  3   6.7   3.7
 12000   9.0  48.2  095   8  4   9.5   5.2 |   8.5  47.3  065   6  3   8.7   4.8
 11750   9.6  49.3  095   7  4   9.5   5.2 |   8.9  48.0  070   6  3   9.0   5.0
 11500  10.2  50.4  095   7  4   8.4   4.6 |   9.4  48.9  070   6  3   8.5   4.7
 11250  10.6  51.1  095   7  3   6.9   3.8 |   9.9  49.8  070   6  3   7.5   4.1
 11000  11.1  52.0  095   6  3   7.4   4.0 |  10.4  50.7  075   5  3   8.6   4.7
 10750  11.6  52.9  095   6  3   7.4   4.1 |  10.9  51.6  080   5  3   9.3   5.1
 10500  12.0  53.6  095   5  3   7.3   4.0 |  11.5  52.7  080   5  3   9.4   5.2
 10250  12.5  54.5  090   5  2   7.2   3.9 |  12.2  54.0  085   5  3   9.8   5.4
 10000  13.0  55.4  080   4  2   7.2   4.0 |  12.9  55.2  085   5  3   9.6   5.3
  9750  13.5  56.3  070   4  2   6.9   3.8 |  13.5  56.3  090   5  3   8.7   4.8
  9500  14.5  58.1  055   4  2   7.3   4.0 |  14.9  58.8  095   5  3  10.6   5.8
  9250  15.0  59.0  055   4  2   7.0   3.9 |  15.7  60.3  095   5  3  10.6   5.8
  9000  15.5  59.9  055   4  2   7.8   4.3 |  16.5  61.7  095   5  3   9.7   5.3
  8750  16.1  61.0  050   4  2   8.3   4.5 |  17.2  63.0  095   5  3   9.8   5.4
  8500  16.7  62.1  045   4  2   7.9   4.3 |  18.0  64.4  100   5  3  10.9   6.0
  8250  17.2  63.0  035   3  2   7.8   4.3 |  18.8  65.8  100   5  3  10.5   5.8
  8000  17.8  64.0  030   3  1   8.4   4.6 |  19.5  67.1  100   5  3  10.8   5.9
  7750  18.4  65.1  030   2  1  14.2   7.8 |  20.5  68.9  105   5  3  17.2   9.5
  7500  19.7  67.5  035   2  1  22.0  12.1 |  22.1  71.8  105   5  3  27.1  14.9
  7250  21.0  69.8  040   1  1   8.9   4.9 |  23.8  74.8  105   6  3   9.9   5.4
  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

           07/31/2015 at 1500 MDT          |       07/31/2015 at 1800 MDT
                                           |
K index... +27.7  LI... +269.5             | K index... +29.7  LI... +269.5
CAPE... +943.2  CIN... -0.6                | CAPE... +682.2  CIN... -3.0
                                           |
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 -68.0 -90.4  270  30 15   1.6   0.9 | -68.0 -90.4  275  33 17   0.4   0.2
 45000 -62.3 -80.1  270  43 22   6.9   3.8 | -63.2 -81.8  270  46 24   7.4   4.1
 40000 -51.4 -60.5  270  46 24   8.6   4.7 | -51.6 -60.9  265  46 24   9.1   5.0
 38000 -46.2 -51.2  270  44 22   8.6   4.7 | -46.1 -51.0  265  39 20   9.1   5.0
 36000 -41.1 -42.0  265  41 21   8.3   4.6 | -40.7 -41.3  260  32 16   8.7   4.8
 34000 -36.1 -33.0  265  36 18   8.3   4.5 | -35.5 -31.9  265  27 14   8.6   4.7
 32000 -31.1 -24.0  270  30 16   8.9   4.9 | -30.3 -22.5  275  23 12   9.2   5.1
 30000 -26.7 -16.1  280  25 13   7.3   4.0 | -26.0 -14.8  285  20 10   7.3   4.0
 29000 -24.6 -12.3  285  22 11   7.3   4.0 | -23.8 -10.8  295  19 10   7.3   4.0
 28000 -21.9  -7.4  295  20 10   6.8   3.7 | -21.2  -6.2  305  18  9   6.4   3.5
 27000 -19.9  -3.8  295  17  9   6.8   3.7 | -19.3  -2.7  310  17  9   6.4   3.5
 26000 -17.9  -0.2  295  15  8   6.8   3.7 | -17.4   0.7  315  16  8   6.5   3.5
 25000 -15.9   3.4  300  13  7   6.8   3.8 | -15.5   4.1  320  15  8   6.0   3.3
 24000 -13.9   7.0  295  12  6   6.8   3.8 | -13.8   7.2  325  15  8   5.9   3.3
 23000 -11.8  10.8  295  11  6   6.9   3.8 | -12.1  10.2  330  15  8   6.0   3.3
 22000  -9.8  14.4  295  10  5   5.7   3.1 | -10.3  13.5  335  15  8   5.9   3.2
 21000  -8.2  17.2  305  11  6   5.8   3.2 |  -8.6  16.5  345  12  6   5.9   3.2
 20000  -6.5  20.3  315  12  6   5.8   3.2 |  -6.9  19.6  360  10  5   5.9   3.2
 19500  -5.7  21.7  320  13  7   5.5   3.0 |  -6.1  21.0  010   9  5   5.9   3.2
 19000  -4.9  23.2  325  12  6   5.0   2.8 |  -5.2  22.6  025   8  4   5.7   3.2
 18500  -4.2  24.4  330  12  6   4.9   2.7 |  -4.4  24.1  040   8  4   5.7   3.1
 18000  -3.5  25.7  340  11  6   5.7   3.1 |  -3.6  25.5  060   8  4   6.0   3.3
 17500  -2.6  27.3  345  10  5   5.7   3.1 |  -2.7  27.1  080   8  4   6.1   3.3
 17000  -1.8  28.8  350   9  5   5.8   3.2 |  -1.8  28.8  100   9  5   6.2   3.4
 16500  -0.9  30.4  005   8  4   6.0   3.3 |  -0.9  30.4  110  10  5   6.4   3.5
 16000  -0.0  32.0  025   7  3   6.0   3.3 |  -0.0  32.0  115  11  6   6.4   3.5
 15500   0.9  33.6  045   7  3   6.4   3.5 |   0.9  33.6  120  11  6   6.9   3.8
 15000   1.8  35.2  060   7  4   6.3   3.5 |   1.9  35.4  125  11  6   6.9   3.8
 14500   2.7  36.9  075   8  4   7.0   3.8 |   2.9  37.2  125  11  6   6.7   3.7
 14000   3.7  38.7  080   9  5   7.1   3.9 |   3.8  38.8  125  11  6   6.7   3.7
 13500   4.6  40.3  090   9  5   8.1   4.4 |   4.8  40.6  130  10  5   6.9   3.8
 13000   5.8  42.4  095   9  5   8.5   4.7 |   5.8  42.4  130  10  5   7.0   3.8
 12500   7.0  44.6  100   9  5   7.9   4.3 |   6.8  44.2  130   9  5   7.0   3.8
 12000   8.2  46.8  105   9  5  10.6   5.8 |   7.8  46.0  135   9  4   7.9   4.4
 11750   8.9  48.0  105   9  5  10.3   5.6 |   8.4  47.1  135   9  4   7.6   4.2
 11500   9.6  49.3  110   9  5  10.2   5.6 |   8.9  48.0  135   8  4   8.6   4.7
 11250  10.3  50.5  110   9  5   9.9   5.4 |   9.6  49.3  135   8  4  10.4   5.7
 11000  11.0  51.8  115   9  5  10.1   5.6 |  10.3  50.5  135   8  4  10.0   5.5
 10750  11.8  53.2  115   9  5  10.3   5.6 |  11.0  51.8  140   8  4   9.2   5.1
 10500  13.3  55.9  115   9  5  10.4   5.7 |  12.4  54.3  140   8  4  10.5   5.7
 10250  14.0  57.2  115   9  5  10.3   5.6 |  13.2  55.8  140   8  4  10.4   5.7
 10000  14.8  58.6  115   9  5   9.2   5.0 |  13.9  57.0  140   8  4   8.9   4.9
  9750  15.4  59.7  120   9  5   9.4   5.2 |  14.5  58.1  140   8  4   9.0   4.9
  9500  16.2  61.2  120   9  5  10.3   5.7 |  15.3  59.5  145   8  4  10.3   5.6
  9250  17.0  62.6  120   9  5  10.6   5.8 |  16.0  60.8  145   8  4  10.7   5.9
  9000  17.7  63.9  120   9  5   9.5   5.2 |  16.8  62.2  145   8  4   9.4   5.1
  8750  18.4  65.1  120   9  5   9.6   5.2 |  17.5  63.5  145   8  4   8.9   4.9
  8500  19.2  66.6  120   9  5  10.9   6.0 |  18.2  64.8  145   8  4  10.2   5.6
  8250  20.0  68.0  125   9  5  10.8   5.9 |  18.9  66.0  145   8  4  10.0   5.5
  8000  20.8  69.4  125   9  5  10.4   5.7 |  19.7  67.5  145   8  4  10.5   5.8
  7750  21.7  71.1  125   9  5  15.4   8.5 |  20.4  68.7  145   8  4  11.3   6.2
  7500  23.1  73.6  125   9  4  24.9  13.7 |  21.2  70.2  145   8  4  11.2   6.2
  7250  24.6  76.3  120   8  4   7.8   4.3 |  22.0  71.6  145   7  4  11.8   6.5
  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) 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 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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