Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 011125
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Soaring Forecast
National Weather Service Pueblo, Colorado
0525 MDT Wednesday, July 1, 2015

This forecast is for Wednesday, July 1, 2015:

If the trigger temperature of 79.3 F/26.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 878 ft/min (4.5 m/s)
   Maximum height of thermals.................. 13981 ft MSL (7223 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8366 ft MSL (1608 ft AGL)
Thermal soaring outlook for Thursday 07/02..... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:37:17 / 20:28:23 MDT
Total possible sunshine........... 14 hr 51 min 6 sec (891 min 6 sec)
Altitude of sun at 13:02:53 MDT... 74.10 degrees

Upper air data from numerical model forecast valid on 07/01/2015 at 0600 MDT

Freezing level.................. 16739 ft MSL (9981 ft AGL)
Convective condensation level... 15715 ft MSL (8957 ft AGL)
Lifted condensation level....... 15030 ft MSL (8273 ft AGL)
Lifted index.................... -1.8
K index......................... +29.6

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   320   22   11   0.7   0.4      M     M       M      M    M
 45000  -62.6 -80.7   320   27   14   6.6   3.6      M     M       M      M    M
 40000  -52.2 -62.0   310   26   13   8.4   4.6      M     M       M      M    M
 38000  -47.1 -52.8   305   23   12   8.4   4.6      M     M       M      M    M
 36000  -42.0 -43.6   300   21   11   8.4   4.6      M     M       M      M    M
 34000  -37.0 -34.6   305   20   10   8.4   4.6      M     M       M      M    M
 32000  -32.0 -25.6   305   19   10   9.2   5.0      M     M       M      M    M
 30000  -26.6 -15.9   310   16    8   8.0   4.4   43.3 109.9    12.4      M    M
 29000  -24.3 -11.7   315   15    8   8.0   4.4   42.7 108.8    12.0      M    M
 28000  -22.0  -7.6   320   15    8   7.0   3.8   41.9 107.4    11.5      M    M
 27000  -19.9  -3.8   325   15    8   7.0   3.8   40.8 105.4    10.8      M    M
 26000  -17.8  -0.0   335   16    8   7.0   3.9   39.8 103.7    10.1      M    M
 25000  -15.8   3.6   340   17    9   6.0   3.3   38.9 102.0     9.4      M    M
 24000  -14.1   6.6   340   16    8   5.5   3.0   37.2  99.0     8.1      M    M
 23000  -12.5   9.5   340   16    8   5.5   3.0   35.7  96.3     6.9      M    M
 22000  -10.9  12.4   345   16    8   5.6   3.1   34.3  93.8     5.8      M    M
 21000   -9.2  15.4   345   15    8   5.8   3.2   32.8  91.1     4.5      M    M
 20000   -7.6  18.3   345   14    7   5.9   3.2   31.5  88.7     3.3      M    M
 19500   -6.8  19.8   345   13    7   6.3   3.4   30.9  87.5     2.7      M    M
 19000   -5.7  21.7   345   13    7   8.4   4.6   30.5  86.9     2.3      M    M
 18500   -4.6  23.7   350   13    7   8.3   4.6   30.2  86.4     2.0      M    M
 18000   -3.4  25.9   350   13    7   8.5   4.7   30.0  86.0     1.7      M    M
 17500   -2.1  28.2   345   14    7   8.6   4.7   29.8  85.7     1.5      M    M
 17000   -0.9  30.4   340   14    7   8.5   4.7   29.6  85.3     1.3      M    M
 16500    0.3  32.5   335   15    8   8.2   4.5   29.4  84.9     1.1      M    M
 16000    1.5  34.7   325   17    9   8.2   4.5   29.1  84.5     0.8      M    M
 15500    2.8  37.0   320   18    9   8.5   4.7   28.9  84.1     0.6      M    M
 15000    4.7  40.5   315   18    9   8.6   4.7   28.6  83.5     0.3      M    M
 14500    5.9  42.6   310   17    9   8.7   4.8   28.5  83.2     0.1      M    M
 14000    7.2  45.0   300   15    8   8.7   4.8   28.3  82.9    -0.0    668  3.4
 13500    8.5  47.3   295   13    7   9.2   5.0   28.2  82.7    -0.2    615  3.1
 13000    9.9  49.8   290   13    6   9.2   5.0   28.1  82.5    -0.3    560  2.8
 12500   11.2  52.2   285   12    6   9.5   5.2   28.0  82.5    -0.4    504  2.6
 12000   12.6  54.7   285   11    6   9.3   5.1   27.9  82.3    -0.5    449  2.3
 11750   13.2  55.8   285   11    6   9.1   5.0   27.9  82.2    -0.6    422  2.1
 11500   13.9  57.0   280   11    6   9.7   5.3   27.9  82.2    -0.7    395  2.0
 11250   14.6  58.3   280   11    5   8.9   4.9   27.9  82.2    -0.7    367  1.9
 11000   15.2  59.4   280   10    5   7.7   4.2   27.7  81.9    -0.8    341  1.7
 10750   15.8  60.4   280   10    5   8.2   4.5   27.6  81.7    -1.0    316  1.6
 10500   16.3  61.3   280   10    5   7.6   4.2   27.5  81.4    -1.1    291  1.5
 10250   16.9  62.4   280    9    5   7.1   3.9   27.3  81.1    -1.3    268  1.4
 10000   17.4  63.3   280    8    4   7.5   4.1   27.1  80.8    -1.5    244  1.2
  9750   18.0  64.4   280    7    4   8.0   4.4   26.9  80.5    -1.7    220  1.1
  9500   18.5  65.3   280    7    3   7.1   3.9   26.8  80.2    -1.8    196  1.0
  9250   19.0  66.2   280    6    3   6.0   3.3   26.5  79.7    -2.1    175  0.9
  9000   19.5  67.1   285    5    3   6.4   3.5   26.2  79.2    -2.4    154  0.8
  8750   20.0  68.0   290    4    2   8.1   4.4   26.0  78.9    -2.6    131  0.7
  8500   20.5  68.9   295    4    2   6.4   3.5   25.9  78.6    -2.8    107  0.5
  8250   20.8  69.4   310    4    2   4.0   2.2   25.5  77.9    -3.2     91  0.5
  8000   21.1  70.0   320    5    3   5.1   2.8   25.1  77.2    -3.7     74  0.4
  7750   21.4  70.5   330    6    3   3.0   1.7   24.7  76.5    -4.1     58  0.3
  7500   21.2  70.2   325    6    3  -8.5  -4.6   24.0  75.1    -4.9     56  0.3
  7250   20.2  68.4   325    6    3 -16.4  -9.0   22.5  72.6    -6.4     81  0.4
  7000   19.1  66.4   325    6    3 -10.5  -5.8   21.1  70.1    -7.8    106  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/01/2015 at 0900 MDT          |       07/01/2015 at 1200 MDT
                                           |
K index... +30.7  LI... +269.4             | K index... +31.9  LI... +268.5
CAPE... +911.4  CIN... -96.0               | CAPE... +1467.8  CIN... -15.5
                                           |
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 -66.6 -87.9  330  23 12   1.1   0.6 | -66.8 -88.2  320  20 11   0.5   0.3
 45000 -62.1 -79.8  320  28 15   6.0   3.3 | -62.5 -80.5  315  28 14   6.7   3.7
 40000 -52.3 -62.1  300  27 14   8.7   4.8 | -51.9 -61.4  300  28 15   8.4   4.6
 38000 -47.1 -52.8  300  25 13   8.7   4.8 | -46.9 -52.4  300  26 14   8.4   4.6
 36000 -41.9 -43.4  300  23 12   8.4   4.6 | -41.9 -43.4  305  24 13   8.4   4.6
 34000 -37.0 -34.6  305  22 11   8.2   4.5 | -36.9 -34.4  305  22 11   8.3   4.6
 32000 -32.0 -25.6  315  21 11   9.0   4.9 | -31.9 -25.4  310  20 10   8.8   4.8
 30000 -26.9 -16.4  315  19 10   7.5   4.1 | -26.6 -15.9  310  18  9   7.7   4.2
 29000 -24.7 -12.5  315  18  9   7.5   4.1 | -24.3 -11.7  310  17  9   7.7   4.2
 28000 -22.5  -8.5  315  17  9   7.3   4.0 | -22.1  -7.8  310  17  9   6.9   3.8
 27000 -20.3  -4.5  320  16  8   7.3   4.0 | -20.1  -4.2  310  16  8   6.9   3.8
 26000 -18.1  -0.6  320  16  8   7.3   4.0 | -18.0  -0.4  305  16  8   6.9   3.8
 25000 -16.0   3.2  325  15  8   6.3   3.5 | -16.0   3.2  305  16  8   6.5   3.5
 24000 -14.2   6.4  325  15  8   6.0   3.3 | -14.1   6.6  305  17  9   6.3   3.5
 23000 -12.5   9.5  320  15  8   6.0   3.3 | -12.2  10.0  310  18  9   6.3   3.5
 22000 -10.7  12.7  320  14  7   6.1   3.4 | -10.3  13.5  310  19 10   6.2   3.4
 21000  -8.9  16.0  320  13  7   6.2   3.4 |  -8.5  16.7  310  18  9   6.2   3.4
 20000  -7.1  19.2  320  11  6   6.2   3.4 |  -6.7  19.9  305  17  9   6.3   3.4
 19500  -6.2  20.8  320  10  5   6.3   3.5 |  -5.8  21.6  305  17  9   6.3   3.5
 19000  -5.3  22.5  325  10  5   6.6   3.6 |  -5.0  23.0  305  16  8   6.4   3.5
 18500  -4.4  24.1  325   9  5   6.6   3.6 |  -4.1  24.6  310  14  7   6.5   3.6
 18000  -3.4  25.9  330   9  4   6.8   3.7 |  -3.2  26.2  310  13  7   6.9   3.8
 17500  -2.5  27.5  330   9  5   6.8   3.7 |  -2.3  27.9  320  12  6   7.1   3.9
 17000  -1.5  29.3  335   9  5   6.9   3.8 |  -1.3  29.7  325  12  6   7.3   4.0
 16500  -0.5  31.1  335  10  5   7.2   3.9 |  -0.4  31.3  330  11  6   7.1   3.9
 16000   0.5  32.9  335  11  6   7.1   3.9 |   0.6  33.1  330  11  6   7.0   3.9
 15500   1.6  34.9  335  11  6   8.2   4.5 |   1.8  35.2  330  10  5   8.9   4.9
 15000   3.4  38.1  325  11  6   8.0   4.4 |   3.7  38.7  330   8  4   9.0   4.9
 14500   4.8  40.6  320  11  6  12.6   6.9 |   5.0  41.0  325   7  4   9.0   4.9
 14000   6.6  43.9  310  11  6  12.5   6.9 |   6.4  43.5  320   6  3   9.1   5.0
 13500   8.2  46.8  305  11  6   9.2   5.0 |   7.6  45.7  315   6  3   7.9   4.3
 13000   9.5  49.1  300  11  6   9.1   5.0 |   8.8  47.8  310   5  2   7.9   4.3
 12500  10.8  51.4  295  10  5   8.2   4.5 |   9.8  49.6  315   3  2   6.5   3.6
 12000  12.1  53.8  300  10  5   8.6   4.7 |  10.7  51.3  325   3  1   6.3   3.5
 11750  12.7  54.9  300   9  5   8.8   4.8 |  11.2  52.2  330   2  1   6.2   3.4
 11500  13.4  56.1  300   9  5   7.8   4.3 |  11.6  52.9  340   2  1   7.0   3.8
 11250  13.9  57.0  305   8  4   6.5   3.6 |  12.1  53.8  005   2  1   7.3   4.0
 11000  14.3  57.7  310   7  4   6.5   3.6 |  12.6  54.7  030   3  2   7.0   3.8
 10750  14.8  58.6  315   7  3   6.5   3.6 |  13.0  55.4  040   4  2   6.7   3.7
 10500  15.3  59.5  320   6  3   6.6   3.6 |  13.4  56.1  045   5  3   8.8   4.8
 10250  15.8  60.4  330   6  3   6.9   3.8 |  14.2  57.6  045   6  3  10.8   5.9
 10000  16.2  61.2  335   6  3   5.1   2.8 |  14.9  58.8  045   6  3   9.3   5.1
  9750  16.5  61.7  345   6  3   3.5   1.9 |  15.5  59.9  050   6  3   8.4   4.6
  9500  16.8  62.2  360   6  3   4.7   2.6 |  16.2  61.2  050   7  3   9.5   5.2
  9250  17.1  62.8  005   7  4   5.4   2.9 |  16.9  62.4  050   7  3  10.2   5.6
  9000  17.5  63.5  005   9  4   5.3   2.9 |  17.7  63.9  050   7  3  10.2   5.6
  8750  17.8  64.0  010  10  5   5.5   3.0 |  18.4  65.1  050   7  4  11.1   6.1
  8500  18.2  64.8  010  10  5   6.8   3.8 |  19.2  66.6  050   7  4  10.7   5.9
  8250  18.7  65.7  010  10  5   8.0   4.4 |  20.0  68.0  050   7  4  10.3   5.7
  8000  19.2  66.6  010  11  5   7.0   3.8 |  20.8  69.4  050   7  4   9.8   5.4
  7750  19.7  67.5  010  11  6  10.0   5.5 |  21.5  70.7  050   7  3  12.3   6.7
  7500  20.5  68.9  010  11  5  10.6   5.8 |  22.5  72.5  050   7  4  13.6   7.5
  7250  21.1  70.0  010  10  5   7.5   4.1 |  23.4  74.1  050   7  4  11.6   6.4
  7000  21.7  71.1  010  10  5  10.1   5.5 |  24.3  75.7  050   7  4  13.4   7.3
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/01/2015 at 1500 MDT          |       07/01/2015 at 1800 MDT
                                           |
K index... +31.0  LI... +269.2             | K index... +31.1  LI... +270.1
CAPE... +1241.3  CIN... -1.2               | CAPE... +539.5  CIN... -4.3
                                           |
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 -67.3 -89.1  300  25 13  -0.4  -0.2 | -67.9 -90.2  290  25 13  -1.5  -0.8
 45000 -63.4 -82.1  305  34 18   7.5   4.1 | -64.0 -83.2  285  32 16   9.0   4.9
 40000 -51.7 -61.1  300  36 19   9.1   5.0 | -50.5 -58.9  295  30 16   9.0   5.0
 38000 -46.2 -51.2  300  33 17   9.1   5.0 | -45.1 -49.2  300  31 16   9.0   5.0
 36000 -40.8 -41.4  300  30 16   8.3   4.6 | -39.7 -39.5  305  31 16   8.5   4.7
 34000 -35.9 -32.6  300  24 12   8.0   4.4 | -34.6 -30.3  305  31 16   8.4   4.6
 32000 -31.1 -24.0  305  18  9   8.8   4.8 | -29.0 -20.2  310  31 16   8.6   4.7
 30000 -25.9 -14.6  300  18  9   7.7   4.2 | -24.7 -12.5  310  27 14   7.3   4.0
 29000 -23.7 -10.7  300  18  9   7.7   4.2 | -22.5  -8.5  315  24 13   7.3   4.0
 28000 -21.5  -6.7  300  18  9   7.0   3.9 | -20.5  -4.9  315  22 11   6.6   3.6
 27000 -19.4  -2.9  295  18  9   7.1   3.9 | -18.5  -1.3  320  20 10   6.6   3.6
 26000 -17.3   0.9  290  18  9   7.1   3.9 | -16.6   2.1  325  18  9   6.7   3.6
 25000 -15.2   4.6  290  19 10   6.7   3.7 | -14.6   5.7  335  16  8   6.3   3.5
 24000 -13.2   8.2  295  20 10   6.6   3.6 | -12.8   9.0  340  13  7   6.2   3.4
 23000 -11.3  11.7  295  20 11   6.6   3.6 | -11.1  12.0  350  10  5   6.2   3.4
 22000  -9.4  15.1  300  21 11   6.0   3.3 |  -9.3  15.3  005   8  4   5.7   3.1
 21000  -7.7  18.1  305  20 10   5.8   3.2 |  -7.7  18.1  025   5  3   5.5   3.0
 20000  -6.0  21.2  310  19 10   5.8   3.2 |  -6.1  21.0  065   4  2   5.5   3.0
 19500  -5.2  22.6  310  19 10   5.7   3.2 |  -5.4  22.3  090   4  2   5.5   3.0
 19000  -4.4  24.1  315  18  9   5.6   3.1 |  -4.6  23.7  105   5  3   5.1   2.8
 18500  -3.6  25.5  315  16  8   5.6   3.1 |  -3.9  25.0  120   5  3   5.1   2.8
 18000  -2.8  27.0  315  14  7   6.0   3.3 |  -3.1  26.4  130   6  3   5.1   2.8
 17500  -1.9  28.6  315  12  6   6.1   3.4 |  -2.4  27.7  130   6  3   5.1   2.8
 17000  -1.1  30.0  320  10  5   6.2   3.4 |  -1.7  28.9  135   7  3   5.1   2.8
 16500  -0.2  31.6  325   8  4   6.7   3.7 |  -1.0  30.2  135   7  3   4.7   2.6
 16000   0.7  33.3  340   6  3   6.7   3.7 |  -0.3  31.5  135   6  3   4.6   2.5
 15500   1.7  35.1  355   5  2   7.1   3.9 |   1.1  34.0  135   6  3   8.1   4.4
 15000   3.2  37.8  060   2  1   7.2   3.9 |   2.2  36.0  140   5  3   8.1   4.4
 14500   4.2  39.6  100   4  2   7.8   4.3 |   3.3  37.9  140   5  3   7.2   4.0
 14000   5.3  41.5  110   5  3   7.8   4.3 |   4.4  39.9  135   5  2   7.3   4.0
 13500   6.4  43.5  115   7  3   9.0   4.9 |   5.4  41.7  125   4  2   7.2   4.0
 13000   7.7  45.9  110   7  4   9.3   5.1 |   6.4  43.5  115   4  2   7.2   4.0
 12500   8.9  48.0  110   7  4   9.3   5.1 |   7.5  45.5  100   3  2   7.9   4.3
 12000  10.4  50.7  110   7  4  10.3   5.6 |   8.6  47.5  090   3  2   7.8   4.3
 11750  11.1  52.0  110   8  4  10.1   5.6 |   9.1  48.4  090   3  2   7.5   4.1
 11500  11.9  53.4  110   8  4  11.3   6.2 |   9.7  49.5  085   3  2   9.6   5.3
 11250  12.7  54.9  110   7  4  10.6   5.8 |  10.4  50.7  080   3  2   9.8   5.4
 11000  13.4  56.1  110   7  4   9.1   5.0 |  11.0  51.8  075   3  2   7.8   4.3
 10750  14.1  57.4  110   7  4   9.4   5.1 |  11.6  52.9  075   3  2   8.0   4.4
 10500  14.8  58.6  110   7  4   9.9   5.4 |  12.1  53.8  070   3  2   8.6   4.7
 10250  15.6  60.1  110   7  4  10.6   5.8 |  12.8  55.0  070   3  2   9.5   5.2
 10000  16.4  61.5  110   7  4  10.0   5.5 |  13.5  56.3  065   4  2   8.5   4.7
  9750  17.1  62.8  110   7  4   9.8   5.4 |  14.1  57.4  065   4  2   7.7   4.2
  9500  17.8  64.0  110   7  4   9.7   5.3 |  14.6  58.3  065   4  2   8.8   4.8
  9250  18.5  65.3  110   7  4   9.4   5.1 |  15.3  59.5  065   4  2   9.5   5.2
  9000  19.3  66.7  110   7  4   9.9   5.4 |  16.0  60.8  065   4  2   9.3   5.1
  8750  20.0  68.0  110   7  4  11.1   6.1 |  16.7  62.1  065   4  2   9.6   5.3
  8500  20.8  69.4  110   7  4  10.8   5.9 |  17.4  63.3  070   4  2   9.6   5.3
  8250  21.6  70.9  110   7  4  10.4   5.7 |  18.1  64.6  070   4  2   9.5   5.2
  8000  22.4  72.3  110   7  4   9.9   5.4 |  18.8  65.8  070   4  2   9.7   5.3
  7750  23.1  73.6  110   7  4  12.2   6.7 |  19.5  67.1  070   5  2   9.2   5.1
  7500  24.1  75.4  110   7  4  13.2   7.2 |  20.1  68.2  075   4  2   6.9   3.8
  7250  25.0  77.0  110   7  4  11.1   6.1 |  20.5  68.9  070   4  2   5.4   3.0
  7000  25.8  78.4  110   7  3  12.9   7.1 |  20.9  69.6  070   4  2   6.5   3.6
  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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