Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 301246
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0646 MDT Tuesday, June 30, 2015

This forecast is for Tuesday, June 30, 2015:

If the trigger temperature of 74.1 F/23.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 918 ft/min (4.7 m/s)
   Maximum height of thermals.................. 17300 ft MSL (10542 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14560 ft MSL (7802 ft AGL)
Thermal soaring outlook for Wednesday 07/01.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:36:50 / 20:28:27 MDT
Total possible sunshine........... 14 hr 51 min 37 sec (891 min 37 sec)
Altitude of sun at 13:02:41 MDT... 74.17 degrees

Upper air data from numerical model forecast valid on 06/30/2015 at 0600 MDT

Freezing level.................. 16970 ft MSL (10212 ft AGL)
Convective condensation level... 15055 ft MSL (8297 ft AGL)
Lifted condensation level....... 15846 ft MSL (9088 ft AGL)
Lifted index.................... -5.2
K index......................... +17.1

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  -64.8 -84.6   015   23   12   2.5   1.4      M     M       M      M    M
 45000  -60.3 -76.5   020   33   17   3.5   1.9      M     M       M      M    M
 40000  -54.0 -65.2   025   41   21   8.0   4.4      M     M       M      M    M
 38000  -49.2 -56.6   025   36   18   8.0   4.4      M     M       M      M    M
 36000  -44.4 -47.9   020   30   15   8.2   4.5      M     M       M      M    M
 34000  -39.4 -38.9   010   26   13   8.4   4.6      M     M       M      M    M
 32000  -34.3 -29.7   360   23   12   8.7   4.8      M     M       M      M    M
 30000  -28.6 -19.5   360   23   12   8.4   4.6   40.9 105.6     8.5      M    M
 29000  -26.1 -15.0   360   23   12   8.4   4.6   40.5 104.9     8.3      M    M
 28000  -23.7 -10.7   360   23   12   7.1   3.9   39.8 103.7     7.8      M    M
 27000  -21.6  -6.9   005   23   12   7.2   4.0   38.8 101.8     7.1      M    M
 26000  -19.4  -2.9   005   22   12   7.2   4.0   37.9 100.2     6.4      M    M
 25000  -17.3   0.9   005   22   11   7.5   4.1   37.1  98.7     5.8      M    M
 24000  -15.0   5.0   005   21   11   7.6   4.2   36.2  97.2     5.1      M    M
 23000  -12.7   9.1   005   21   11   7.7   4.2   35.5  95.8     4.5      M    M
 22000  -10.5  13.1   010   20   10   7.3   4.0   34.8  94.6     4.0      M    M
 21000   -8.3  17.1   010   21   11   7.2   3.9   33.8  92.8     3.1      M    M
 20000   -6.2  20.8   005   21   11   7.2   4.0   33.0  91.3     2.4      M    M
 19500   -5.2  22.6   005   21   11   7.4   4.1   32.6  90.6     2.0      M    M
 19000   -4.0  24.8   005   21   11   7.9   4.3   32.2  90.0     1.7      M    M
 18500   -2.8  27.0   010   22   11   8.0   4.4   31.9  89.4     1.4      M    M
 18000   -1.8  28.8   005   22   11   5.8   3.2   31.5  88.7     1.1      M    M
 17500   -1.0  30.2   005   21   11   5.3   2.9   30.7  87.3     0.4      M    M
 17000   -0.2  31.6   360   20   10   5.3   2.9   30.0  86.0    -0.3    902  4.6
 16500    0.6  33.1   355   20   10   5.8   3.2   29.3  84.7    -1.0    864  4.4
 16000    1.4  34.5   350   19   10   5.7   3.1   28.7  83.6    -1.6    825  4.2
 15500    2.3  36.1   345   18   10   8.2   4.5   28.2  82.7    -2.2    783  4.0
 15000    4.0  39.2   340   17    9   8.6   4.7   27.8  82.1    -2.7    710  3.6
 14500    5.0  41.0   335   15    8   7.3   4.0   27.5  81.6    -3.2    664  3.4
 14000    6.1  43.0   325   13    7   7.5   4.1   27.2  80.9    -3.6    618  3.1
 13500    7.1  44.8   315   11    5   7.1   3.9   26.8  80.2    -4.1    573  2.9
 13000    8.1  46.6   305    8    4   7.2   3.9   26.3  79.4    -4.6    528  2.7
 12500    9.1  48.4   285    7    3   7.1   3.9   25.9  78.6    -5.0    484  2.5
 12000   10.2  50.4   275    6    3   7.8   4.3   25.6  78.0    -5.4    436  2.2
 11750   10.7  51.3   270    6    3   7.8   4.3   25.4  77.8    -5.6    412  2.1
 11500   11.3  52.3   265    6    3   8.0   4.4   25.3  77.5    -5.8    388  2.0
 11250   11.8  53.2   260    6    3   7.8   4.3   25.1  77.3    -6.0    364  1.8
 11000   12.4  54.3   255    6    3   7.6   4.2   25.0  77.0    -6.2    340  1.7
 10750   12.9  55.2   245    6    3   7.6   4.2   24.8  76.7    -6.4    317  1.6
 10500   13.5  56.3   240    6    3   8.1   4.4   24.7  76.4    -6.6    293  1.5
 10250   14.1  57.4   235    7    3   8.6   4.7   24.6  76.2    -6.8    268  1.4
 10000   14.6  58.3   230    7    4   8.2   4.5   24.5  76.0    -6.9    243  1.2
  9750   15.2  59.4   230    8    4   8.0   4.4   24.3  75.8    -7.1    218  1.1
  9500   15.8  60.4   225    8    4   8.0   4.4   24.2  75.5    -7.2    193  1.0
  9250   16.4  61.5   225    9    5   7.9   4.3   24.0  75.3    -7.4    168  0.9
  9000   17.0  62.6   225    9    5   7.9   4.4   23.9  75.0    -7.6    144  0.7
  8750   17.5  63.5   220   10    5   7.4   4.1   23.8  74.8    -7.7    119  0.6
  8500   18.1  64.6   220   10    5   6.1   3.3   23.5  74.4    -8.0     96  0.5
  8250   18.4  65.1   220   10    5   4.1   2.2   23.2  73.7    -8.3     77  0.4
  8000   18.8  65.8   220   10    5   8.7   4.8   22.8  73.1    -8.7     59  0.3
  7750   19.2  66.6   220    9    5  -7.7  -4.2   22.5  72.5    -9.1     40  0.2
  7500   17.8  64.0   225    9    5 -17.6  -9.7   20.6  69.0   -11.0     74  0.4
  7250   17.1  62.8   230    8    4  -5.9  -3.3   19.5  67.0   -12.1     89  0.5
  7000   16.3  61.3   245    6    3 -16.2  -8.9   18.4  65.0   -13.3    103  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           06/30/2015 at 0900 MDT          |       06/30/2015 at 1200 MDT
                                           |
K index... +17.3  LI... +271.7             | K index... +16.4  LI... +270.2
CAPE... +559.2  CIN... -84.8               | CAPE... +1133.3  CIN... -22.0
                                           |
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 -65.5 -85.9  005  22 11   1.8   1.0 | -66.4 -87.5  360  22 11   0.9   0.5
 45000 -61.2 -78.2  015  30 16   4.5   2.5 | -62.4 -80.3  005  29 15   5.6   3.1
 40000 -53.6 -64.5  020  35 18   8.0   4.4 | -53.2 -63.8  020  32 17   8.2   4.5
 38000 -48.8 -55.8  020  32 17   8.0   4.4 | -48.3 -54.9  015  30 15   8.2   4.5
 36000 -44.4 -47.9  015  29 15   8.3   4.6 | -43.4 -46.1  010  27 14   8.5   4.6
 34000 -38.7 -37.7  015  26 13   8.7   4.8 | -38.2 -36.8  005  22 11   8.6   4.7
 32000 -33.5 -28.3  010  23 12   9.2   5.0 | -33.0 -27.4  360  17  9   9.0   5.0
 30000 -28.0 -18.4  005  21 11   8.1   4.4 | -27.4 -17.3  350  17  9   8.3   4.5
 29000 -25.6 -14.1  360  21 11   8.1   4.4 | -25.0 -13.0  350  17  9   8.2   4.5
 28000 -23.3  -9.9  360  20 10   6.9   3.8 | -22.7  -8.9  345  17  9   6.9   3.8
 27000 -21.2  -6.2  360  20 10   7.0   3.8 | -20.6  -5.1  340  17  9   6.9   3.8
 26000 -19.1  -2.4  360  19 10   7.0   3.8 | -18.5  -1.3  340  16  8   6.9   3.8
 25000 -17.0   1.4  360  19 10   7.0   3.9 | -16.4   2.5  335  16  8   6.8   3.7
 24000 -14.9   5.2  360  19 10   7.0   3.9 | -14.4   6.1  340  16  8   6.7   3.7
 23000 -12.8   9.0  360  18 10   7.0   3.9 | -12.4   9.7  340  17  9   6.7   3.7
 22000 -10.7  12.7  360  18  9   7.3   4.0 | -10.4  13.3  345  17  9   6.9   3.8
 21000  -8.6  16.5  360  19 10   7.3   4.0 |  -8.3  17.1  350  18  9   6.9   3.8
 20000  -6.4  20.5  360  20 10   7.4   4.1 |  -6.2  20.8  350  18  9   7.0   3.8
 19500  -5.3  22.5  360  20 10   7.7   4.2 |  -5.2  22.6  355  19 10   7.2   4.0
 19000  -4.1  24.6  360  20 10   8.5   4.7 |  -4.0  24.8  355  19 10   7.9   4.3
 18500  -2.9  26.8  360  19 10   8.6   4.7 |  -2.9  26.8  355  20 10   7.9   4.4
 18000  -1.7  28.9  360  19 10   7.0   3.8 |  -1.7  28.9  355  20 10   7.9   4.3
 17500  -0.7  30.7  360  18  9   6.7   3.7 |  -0.6  30.9  355  21 11   7.9   4.3
 17000   0.3  32.5  360  18  9   6.6   3.6 |   0.6  33.1  355  21 11   7.8   4.3
 16500   1.2  34.2  355  18  9   6.3   3.5 |   1.7  35.1  355  22 11   7.5   4.1
 16000   2.1  35.8  350  18  9   6.2   3.4 |   2.8  37.0  355  22 12   7.5   4.1
 15500   3.1  37.6  345  18  9   7.3   4.0 |   3.9  39.0  355  23 12   7.4   4.0
 15000   4.6  40.3  335  17  9   7.6   4.2 |   5.5  41.9  350  22 12   7.4   4.0
 14500   5.7  42.3  330  16  8   9.0   5.0 |   6.6  43.9  345  21 11   7.8   4.3
 14000   6.9  44.4  330  15  8   9.1   5.0 |   7.6  45.7  345  20 10   7.7   4.2
 13500   8.1  46.6  325  14  7   8.2   4.5 |   8.8  47.8  340  19 10   8.8   4.8
 13000   9.2  48.6  315  12  6   8.3   4.6 |  10.0  50.0  340  17  9   9.0   4.9
 12500  10.3  50.5  305  10  5   7.3   4.0 |  11.2  52.2  335  16  8   8.5   4.7
 12000  11.4  52.5  295   9  5   7.9   4.3 |  12.4  54.3  330  14  7   9.2   5.0
 11750  12.0  53.6  290   9  5   7.9   4.4 |  13.0  55.4  330  13  7   9.3   5.1
 11500  12.6  54.7  280   9  5   7.7   4.2 |  13.6  56.5  325  12  6   9.5   5.2
 11250  13.1  55.6  275   9  5   7.3   4.0 |  14.2  57.6  320  10  5   9.2   5.1
 11000  13.6  56.5  270  10  5   7.3   4.0 |  14.8  58.6  315   9  5   9.0   4.9
 10750  14.2  57.6  270  11  5   7.3   4.0 |  15.5  59.9  315   8  4   9.1   5.0
 10500  14.7  58.5  265  11  6   7.4   4.1 |  16.1  61.0  310   7  3   8.6   4.7
 10250  15.2  59.4  265  11  6   7.6   4.2 |  16.7  62.1  300   5  3   8.1   4.4
 10000  15.8  60.4  260  11  6   7.1   3.9 |  17.3  63.1  285   4  2   8.8   4.8
  9750  16.3  61.3  260  11  6   6.7   3.7 |  17.9  64.2  275   4  2   9.1   5.0
  9500  16.8  62.2  255  11  5   7.0   3.9 |  18.6  65.5  260   3  2   9.3   5.1
  9250  17.3  63.1  255  10  5   7.2   4.0 |  19.3  66.7  255   3  2   9.6   5.3
  9000  17.9  64.2  250  10  5   7.1   3.9 |  20.0  68.0  250   3  2   9.7   5.3
  8750  18.4  65.1  250  10  5   7.1   3.9 |  20.7  69.3  245   3  1  10.0   5.5
  8500  18.9  66.0  250  10  5   7.4   4.1 |  21.5  70.7  235   3  1  10.3   5.6
  8250  19.4  66.9  245   9  5   7.9   4.3 |  22.3  72.1  230   3  1  10.6   5.8
  8000  19.9  67.8  240   8  4   7.3   4.0 |  23.0  73.4  225   3  1   9.9   5.4
  7750  20.4  68.7  235   7  4   9.6   5.3 |  23.8  74.8  220   3  1  12.3   6.7
  7500  21.2  70.2  230   6  3  10.1   5.5 |  24.8  76.6  210   3  1  13.0   7.1
  7250  21.8  71.2  225   6  3   7.6   4.2 |  25.6  78.1  210   3  1  10.7   5.9
  7000  22.3  72.1  225   6  3   9.7   5.3 |  26.4  79.5  210   3  1  12.7   6.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/30/2015 at 1500 MDT          |       06/30/2015 at 1800 MDT
                                           |
K index... +21.3  LI... +270.5             | K index... +29.7  LI... +269.7
CAPE... +1028.6  CIN... -17.0              | CAPE... +1243.9  CIN... -30.0
                                           |
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 -66.7 -88.1  360  20 10   0.1   0.1 | -67.1 -88.8  360  16  8   0.3   0.1
 45000 -63.0 -81.4  005  28 14   6.4   3.5 | -63.0 -81.4  005  25 13   6.7   3.7
 40000 -52.8 -63.0  010  28 15   8.2   4.5 | -52.4 -62.3  355  28 14   8.5   4.6
 38000 -47.9 -54.2  010  24 12   8.2   4.5 | -47.3 -53.1  345  24 12   8.5   4.6
 36000 -43.0 -45.4  010  20 10   8.5   4.7 | -42.2 -44.0  335  21 11   8.7   4.8
 34000 -37.8 -36.0  355  16  8   8.7   4.8 | -36.9 -34.4  330  17  9   8.9   4.9
 32000 -31.9 -25.4  325  14  7   8.8   4.8 | -31.0 -23.8  315  14  7   8.5   4.6
 30000 -27.0 -16.6  330  15  8   8.2   4.5 | -26.3 -15.3  325  16  8   7.8   4.3
 29000 -24.5 -12.1  330  16  8   8.2   4.5 | -24.0 -11.2  325  17  9   7.8   4.3
 28000 -22.3  -8.1  330  17  9   6.8   3.8 | -21.7  -7.1  330  19 10   7.1   3.9
 27000 -20.2  -4.4  330  18  9   6.9   3.8 | -19.6  -3.3  330  21 11   7.1   3.9
 26000 -18.1  -0.6  330  20 10   6.9   3.8 | -17.4   0.7  325  23 12   7.1   3.9
 25000 -16.1   3.0  330  21 11   6.8   3.7 | -15.3   4.5  325  25 13   6.5   3.5
 24000 -14.1   6.6  335  22 11   6.8   3.7 | -13.5   7.7  325  25 13   6.3   3.4
 23000 -12.1  10.2  335  22 11   6.8   3.7 | -11.6  11.1  330  26 13   6.3   3.4
 22000 -10.1  13.8  340  22 12   6.8   3.8 |  -9.8  14.4  330  26 13   6.7   3.7
 21000  -8.0  17.6  340  22 12   6.9   3.8 |  -7.8  18.0  330  25 13   6.9   3.8
 20000  -6.0  21.2  340  23 12   6.9   3.8 |  -5.9  21.4  325  25 13   7.0   3.9
 19500  -5.0  23.0  340  23 12   7.0   3.8 |  -4.9  23.2  325  24 13   7.2   3.9
 19000  -3.9  25.0  345  23 12   7.4   4.1 |  -3.9  25.0  325  24 12   7.3   4.0
 18500  -2.8  27.0  345  23 12   7.4   4.0 |  -2.8  27.0  325  23 12   7.3   4.0
 18000  -1.7  28.9  350  23 12   7.9   4.4 |  -1.8  28.8  330  21 11   7.6   4.1
 17500  -0.5  31.1  350  23 12   8.1   4.4 |  -0.7  30.7  330  20 10   7.7   4.2
 17000   0.6  33.1  355  23 12   8.2   4.5 |   0.4  32.7  330  19 10   7.8   4.3
 16500   1.8  35.2  355  23 12   8.4   4.6 |   1.6  34.9  330  18  9   8.5   4.7
 16000   3.0  37.4  355  23 12   8.5   4.6 |   2.9  37.2  335  16  8   8.4   4.6
 15500   4.8  40.6  360  22 12   8.4   4.6 |   4.8  40.6  340  14  7   9.1   5.0
 15000   6.0  42.8  360  22 12   8.5   4.7 |   6.2  43.2  345  13  7   9.1   5.0
 14500   7.1  44.8  360  21 11   8.4   4.6 |   7.5  45.5  350  11  6   8.8   4.8
 14000   8.3  46.9  355  19 10   8.4   4.6 |   8.8  47.8  355   9  5   8.8   4.8
 13500   9.5  49.1  355  17  9   8.8   4.8 |  10.1  50.2  355   8  4   9.4   5.2
 13000  10.8  51.4  355  14  7   8.9   4.9 |  11.4  52.5  355   6  3   9.7   5.3
 12500  12.0  53.6  355  10  5   8.8   4.8 |  12.7  54.9  360   4  2   8.5   4.7
 12000  13.3  55.9  355   8  4   9.2   5.1 |  14.1  57.4  360   3  1   9.1   5.0
 11750  14.0  57.2  360   7  4   9.2   5.0 |  14.7  58.5  360   2  1   9.3   5.1
 11500  14.7  58.5  360   6  3   9.8   5.4 |  15.4  59.7  360   1  1   8.8   4.8
 11250  15.4  59.7  360   5  2   9.7   5.3 |  16.0  60.8  000   0  0   8.2   4.5
 11000  16.1  61.0  360   4  2   9.2   5.0 |  16.6  61.9  220   1  0   8.3   4.5
 10750  16.7  62.1  005   3  2   9.2   5.1 |  17.2  63.0  205   2  1   8.5   4.7
 10500  17.4  63.3  010   2  1   9.6   5.3 |  17.7  63.9  205   3  1   7.7   4.2
 10250  18.1  64.6  010   2  1  10.0   5.5 |  18.2  64.8  205   4  2   6.9   3.8
 10000  18.8  65.8  010   1  1   9.7   5.3 |  18.8  65.8  205   5  3   8.9   4.9
  9750  19.5  67.1  020   1  0   9.6   5.3 |  19.5  67.1  200   6  3  10.4   5.7
  9500  20.2  68.4  045   1  0   9.6   5.2 |  20.2  68.4  200   7  4   9.2   5.0
  9250  20.9  69.6  065   1  0   9.4   5.2 |  20.8  69.4  200   7  4   7.8   4.3
  9000  21.6  70.9  090   1  0   9.7   5.3 |  21.4  70.5  200   8  4   8.5   4.6
  8750  22.4  72.3  110   1  0  10.2   5.6 |  22.1  71.8  195   8  4  10.2   5.6
  8500  23.2  73.8  125   1  0  10.3   5.6 |  22.9  73.2  195   8  4  10.4   5.7
  8250  23.9  75.0  135   1  0  10.2   5.6 |  23.6  74.5  195   8  4  10.0   5.5
  8000  24.7  76.5  140   1  1  10.1   5.6 |  24.3  75.7  195   8  4  10.0   5.5
  7750  25.5  77.9  145   1  1  10.6   5.8 |  25.1  77.2  195   8  4  10.0   5.5
  7500  26.2  79.2  150   1  1  11.8   6.5 |  25.8  78.4  195   9  4   8.7   4.8
  7250  27.1  80.8  145   2  1  12.2   6.7 |  26.3  79.3  190   8  4   7.5   4.1
  7000  27.9  82.2  145   2  1  12.0   6.6 |  26.9  80.4  190   8  4   8.5   4.6
  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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