Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281325
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0725 MDT Saturday, March 28, 2015

This forecast is for Saturday, March 28, 2015:

If the trigger temperature of 58.5 F/14.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1278 ft/min (6.5 m/s)
   Maximum height of thermals.................. 20368 ft MSL (13610 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1000 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................. 17155 ft MSL (10397 ft AGL)
Thermal soaring outlook for Sunday 03/29....... Good

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

Remarks...

Sunrise/Sunset.................... 06:50:10 / 19:17:37 MDT
Total possible sunshine........... 12 hr 27 min 26 sec (747 min 26 sec)
Altitude of sun at 13:04:02 MDT... 54.15 degrees

Upper air data from numerical model forecast valid on 03/28/2015 at 0600 MDT

Freezing level.................. 12251 ft MSL (5493 ft AGL)
Convective condensation level... 15664 ft MSL (8906 ft AGL)
Lifted condensation level....... 17202 ft MSL (10444 ft AGL)
Lifted index.................... -3.3
K index......................... +9.1

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  -61.3 -78.3   335   25   13   3.2   1.8      M     M       M      M    M
 45000  -55.8 -68.4   340   38   20   4.9   2.7      M     M       M      M    M
 40000  -48.4 -55.1   340   55   28   5.4   3.0      M     M       M      M    M
 38000  -47.9 -54.2   340   53   27   0.0   0.0      M     M       M      M    M
 36000  -47.9 -54.2   335   50   26   0.0   0.0      M     M       M      M    M
 34000  -47.1 -52.8   335   48   25   3.5   1.9      M     M       M      M    M
 32000  -45.0 -49.0   335   46   24   3.5   1.9      M     M       M      M    M
 30000  -41.4 -42.5   335   42   22   7.6   4.2   27.8  82.0     4.7      M    M
 29000  -39.1 -38.4   335   40   21   7.6   4.2   26.9  80.4     4.1      M    M
 28000  -36.9 -34.4   335   38   20   7.6   4.2   26.2  79.1     3.5      M    M
 27000  -34.4 -29.9   335   37   19   8.6   4.7   25.5  78.0     3.1      M    M
 26000  -31.9 -25.4   335   35   18   8.6   4.7   25.0  77.1     2.7      M    M
 25000  -29.3 -20.7   335   34   17   8.6   4.7   24.7  76.4     2.4      M    M
 24000  -26.8 -16.2   335   32   16   8.0   4.4   24.2  75.6     2.1      M    M
 23000  -24.4 -11.9   335   30   15   8.0   4.4   23.5  74.3     1.5      M    M
 22000  -22.0  -7.6   335   28   14   8.0   4.4   22.9  73.3     1.1      M    M
 21000  -19.7  -3.5   335   27   14   7.5   4.1   22.3  72.1     0.5      M    M
 20000  -17.4   0.7   340   26   13   7.5   4.1   21.5  70.6    -0.2   1246  6.3
 19500  -16.3   2.7   340   26   13   7.5   4.1   21.1  70.0    -0.5   1198  6.1
 19000  -15.2   4.6   340   25   13   7.3   4.0   20.8  69.4    -0.8   1149  5.8
 18500  -14.2   6.4   335   25   13   5.9   3.2   20.2  68.4    -1.3   1106  5.6
 18000  -13.3   8.1   335   25   13   6.0   3.3   19.6  67.2    -1.9   1064  5.4
 17500  -12.4   9.7   335   25   13   6.2   3.4   19.0  66.1    -2.5   1022  5.2
 17000  -11.5  11.3   330   25   13   6.3   3.4   18.4  65.0    -3.1    980  5.0
 16500  -10.6  12.9   330   26   13   6.7   3.7   17.8  64.0    -3.6    938  4.8
 16000   -9.5  14.9   330   26   13   7.7   4.2   17.4  63.3    -4.0    890  4.5
 15500   -8.4  16.9   330   26   13   7.7   4.2   17.1  62.7    -4.4    842  4.3
 15000   -7.2  19.0   330   26   13   8.3   4.6   16.8  62.2    -4.7    792  4.0
 14500   -5.4  22.3   330   25   13   8.4   4.6   16.4  61.6    -5.1    716  3.6
 14000   -4.2  24.4   330   25   13   8.5   4.7   16.2  61.2    -5.4    665  3.4
 13500   -3.0  26.6   330   24   12   8.6   4.7   16.0  60.8    -5.7    613  3.1
 13000   -1.7  28.9   330   23   12   8.9   4.9   15.8  60.5    -5.9    560  2.8
 12500   -0.4  31.3   330   21   11   8.4   4.6   15.7  60.3    -6.1    507  2.6
 12000    0.9  33.6   330   22   11   9.4   5.2   15.6  60.0    -6.3    454  2.3
 11750    1.5  34.7   330   22   12   9.2   5.0   15.5  59.9    -6.4    427  2.2
 11500    2.2  36.0   330   23   12   9.2   5.1   15.5  59.8    -6.5    399  2.0
 11250    2.9  37.2   330   24   12   9.3   5.1   15.4  59.8    -6.6    371  1.9
 11000    3.6  38.5   330   24   12   9.2   5.1   15.4  59.7    -6.6    343  1.7
 10750    4.3  39.7   330   24   12   9.2   5.0   15.4  59.6    -6.7    316  1.6
 10500    4.9  40.8   330   24   12   9.2   5.0   15.3  59.6    -6.8    288  1.5
 10250    5.6  42.1   330   24   12   8.6   4.7   15.3  59.5    -6.8    261  1.3
 10000    6.2  43.2   330   24   12   8.8   4.8   15.2  59.3    -6.9    234  1.2
  9750    6.9  44.4   330   24   12   9.6   5.2   15.1  59.2    -7.0    206  1.0
  9500    7.6  45.7   330   23   12   9.3   5.1   15.1  59.2    -7.0    177  0.9
  9250    8.3  46.9   325   23   12   8.6   4.7   15.0  59.1    -7.1    150  0.8
  9000    8.9  48.0   325   23   12   8.0   4.4   14.9  58.9    -7.2    123  0.6
  8750    9.6  49.3   325   23   12  10.0   5.5   14.8  58.7    -7.3     97  0.5
  8500   10.3  50.5   320   23   12   7.0   3.8   14.8  58.7    -7.4     68  0.3
  8250   10.6  51.1   320   22   11   1.1   0.6   14.4  57.8    -7.9     53  0.3
  8000   10.6  51.1   315   22   11  -0.2  -0.1   13.6  56.6    -8.6     45  0.2
  7750   10.6  51.1   310   21   11   2.3   1.2   12.9  55.3    -9.3     36  0.2
  7500   10.3  50.5   305   20   11 -18.3 -10.1   12.0  53.5   -10.4     39  0.2
  7250    7.8  46.0   300   17    9 -39.5 -21.7    9.1  48.4   -13.2    106  0.5
  7000    5.3  41.5   300   13    7 -23.3 -12.8    6.3  43.3   -16.0    174  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           03/28/2015 at 0900 MDT          |       03/28/2015 at 1200 MDT
                                           |
K index... -0.8  LI... +276.6              | K index... -0.8  LI... +274.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -38.7
                                           |
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 -61.2 -78.2  330  26 14   3.7   2.0 | -61.6 -78.9  325  24 13   3.3   1.8
 45000 -55.1 -67.2  330  36 19   4.5   2.4 | -55.8 -68.4  330  40 21   5.1   2.8
 40000 -48.4 -55.1  330  47 24   4.8   2.6 | -48.2 -54.8  320  45 23   5.3   2.9
 38000 -47.5 -53.5  330  48 25   1.1   0.6 | -46.4 -51.5  315  45 23   2.8   1.5
 36000 -46.8 -52.2  330  49 25   1.1   0.6 | -44.7 -48.5  315  46 24   2.8   1.5
 34000 -45.9 -50.6  330  49 25   2.3   1.2 | -43.8 -46.8  315  46 24  -0.5  -0.3
 32000 -44.4 -47.9  330  48 25   2.3   1.2 | -44.1 -47.4  315  47 24  -0.5  -0.3
 30000 -41.4 -42.5  335  46 24   7.6   4.2 | -41.8 -43.2  315  45 23   8.1   4.5
 29000 -39.1 -38.4  335  45 23   7.6   4.2 | -39.4 -38.9  315  43 22   8.2   4.5
 28000 -36.8 -34.2  335  44 22   7.7   4.2 | -36.9 -34.4  315  40 21   8.2   4.5
 27000 -34.4 -29.9  335  42 22   8.5   4.7 | -34.5 -30.1  315  38 20   8.3   4.6
 26000 -31.9 -25.4  335  41 21   8.5   4.7 | -32.0 -25.6  315  37 19   8.3   4.6
 25000 -29.3 -20.7  335  41 21   8.5   4.7 | -29.5 -21.1  315  35 18   8.3   4.6
 24000 -26.7 -16.1  335  38 20   8.9   4.9 | -26.9 -16.4  315  33 17   9.1   5.0
 23000 -24.0 -11.2  330  34 18   8.9   4.9 | -24.2 -11.6  310  31 16   9.1   5.0
 22000 -21.4  -6.5  325  31 16   8.8   4.8 | -21.5  -6.7  310  28 15   9.0   5.0
 21000 -18.9  -2.0  320  27 14   7.7   4.2 | -18.9  -2.0  310  26 14   8.0   4.4
 20000 -16.6   2.1  320  25 13   7.7   4.2 | -16.5   2.3  310  24 13   7.9   4.3
 19500 -15.4   4.3  320  24 12   7.7   4.2 | -15.4   4.3  310  24 12   7.9   4.3
 19000 -14.3   6.3  315  23 12   7.4   4.0 | -14.2   6.4  310  23 12   7.7   4.2
 18500 -13.4   7.9  315  22 11   5.2   2.8 | -13.1   8.4  310  21 11   6.5   3.6
 18000 -12.6   9.3  315  21 11   5.3   2.9 | -12.1  10.2  310  20 10   6.7   3.7
 17500 -11.8  10.8  320  20 10   5.7   3.1 | -11.2  11.8  310  18  9   5.2   2.9
 17000 -10.9  12.4  320  19 10   5.8   3.2 | -10.5  13.1  305  16  8   5.0   2.7
 16500 -10.1  13.8  325  18 10   6.2   3.4 |  -9.8  14.4  305  14  7   5.4   3.0
 16000  -9.1  15.6  325  18  9   7.1   3.9 |  -8.9  16.0  300  13  7   6.3   3.5
 15500  -7.5  18.5  330  17  9   7.7   4.2 |  -7.5  18.5  290  11  5   7.3   4.0
 15000  -6.3  20.7  330  16  8   8.2   4.5 |  -6.3  20.7  285   9  5   7.9   4.4
 14500  -5.1  22.8  330  16  8   8.1   4.4 |  -5.2  22.6  280   8  4   8.1   4.4
 14000  -3.9  25.0  325  14  7   7.7   4.3 |  -4.0  24.8  280   7  4   8.2   4.5
 13500  -2.8  27.0  325  13  6   8.0   4.4 |  -2.8  27.0  290   6  3   8.4   4.6
 13000  -1.5  29.3  320  12  6   9.0   5.0 |  -1.4  29.5  295   6  3   9.6   5.3
 12500  -0.2  31.6  325  12  6   8.3   4.5 |   0.0  32.0  310   6  3   9.2   5.1
 12000   1.1  34.0  325  12  6   9.7   5.3 |   1.4  34.5  315   6  3   9.5   5.2
 11750   1.8  35.2  325  13  7   9.3   5.1 |   2.1  35.8  315   7  3   9.4   5.1
 11500   2.5  36.5  325  13  7   9.5   5.2 |   2.8  37.0  315   7  4   9.4   5.2
 11250   3.2  37.8  330  14  7   9.3   5.1 |   3.5  38.3  320   7  4   9.3   5.1
 11000   3.9  39.0  325  14  7   8.9   4.9 |   4.1  39.4  315   7  4   9.2   5.0
 10750   4.5  40.1  325  15  8   8.7   4.8 |   4.7  40.5  310   7  4   9.2   5.1
 10500   5.1  41.2  325  15  8   8.8   4.8 |   5.4  41.7  300   7  4   9.4   5.1
 10250   5.8  42.4  325  16  8   8.4   4.6 |   6.0  42.8  300   7  4   9.0   4.9
 10000   6.4  43.5  325  16  8   8.6   4.7 |   6.7  44.1  295   7  4   9.3   5.1
  9750   7.1  44.8  325  16  8   9.4   5.1 |   7.4  45.3  295   7  4  10.2   5.6
  9500   7.7  45.9  325  17  9   9.1   5.0 |   8.1  46.6  295   7  3  10.0   5.5
  9250   8.4  47.1  325  17  9   8.4   4.6 |   8.9  48.0  290   7  3   9.5   5.2
  9000   9.0  48.2  320  16  8   8.0   4.4 |   9.6  49.3  290   6  3   9.4   5.1
  8750   9.6  49.3  320  16  8   9.1   5.0 |  10.3  50.5  290   6  3  10.8   5.9
  8500  10.2  50.4  320  16  8   7.3   4.0 |  11.1  52.0  290   6  3  11.1   6.1
  8250  10.6  51.1  315  16  8   3.7   2.0 |  11.9  53.4  290   6  3  10.1   5.5
  8000  10.8  51.4  310  16  8   3.7   2.0 |  12.7  54.9  290   6  3   9.9   5.4
  7750  11.1  52.0  305  16  8   2.4   1.3 |  13.4  56.1  290   6  3  10.4   5.7
  7500  11.0  51.8  300  15  8  -4.1  -2.3 |  14.2  57.6  285   6  3  10.9   6.0
  7250  10.4  50.7  295  12  6  -8.1  -4.5 |  15.0  59.0  285   5  3  10.7   5.9
  7000   9.8  49.6  295   9  5  -5.1  -2.8 |  15.7  60.3  290   5  3  10.9   6.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/28/2015 at 1500 MDT          |       03/28/2015 at 1800 MDT
                                           |
K index... +13.9  LI... +272.7             | K index... +14.8  LI... +271.5
CAPE... +126.2  CIN... -14.5               | CAPE... +229.9  CIN... -9.4
                                           |
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 -61.4 -78.5  305  28 14   3.3   1.8 | -61.9 -79.4  290  29 15   2.9   1.6
 45000 -55.8 -68.4  310  40 21   5.4   3.0 | -56.4 -69.5  305  36 19   5.9   3.2
 40000 -47.7 -53.9  310  41 21   5.5   3.0 | -47.6 -53.7  300  42 22   6.0   3.3
 38000 -45.9 -50.6  305  44 23   2.8   1.5 | -46.0 -50.8  295  46 24   2.2   1.2
 36000 -44.2 -47.6  305  48 25   2.8   1.5 | -44.7 -48.5  295  49 25   2.2   1.2
 34000 -43.3 -45.9  305  49 25  -0.6  -0.4 | -44.0 -47.2  290  51 26  -0.5  -0.3
 32000 -43.8 -46.8  305  47 24  -0.6  -0.3 | -44.2 -47.6  290  49 25  -0.5  -0.2
 30000 -41.4 -42.5  305  46 23   8.3   4.5 | -41.7 -43.1  290  47 24   8.8   4.8
 29000 -38.9 -38.0  310  45 23   8.3   4.6 | -39.1 -38.4  290  47 24   8.8   4.8
 28000 -36.5 -33.7  310  44 23   8.3   4.6 | -36.5 -33.7  295  46 24   8.8   4.8
 27000 -34.0 -29.2  310  42 22   8.3   4.6 | -33.9 -29.0  295  44 23   8.4   4.6
 26000 -31.5 -24.7  310  40 21   8.3   4.6 | -31.4 -24.5  295  42 21   8.4   4.6
 25000 -29.0 -20.2  310  37 19   8.3   4.6 | -28.9 -20.0  295  39 20   8.4   4.6
 24000 -26.5 -15.7  305  35 18   8.4   4.6 | -26.4 -15.5  295  36 19   7.7   4.2
 23000 -23.9 -11.0  300  33 17   8.4   4.6 | -24.1 -11.4  295  33 17   7.7   4.2
 22000 -21.4  -6.5  300  30 16   8.4   4.6 | -21.8  -7.2  300  31 16   7.7   4.2
 21000 -19.0  -2.2  295  29 15   7.5   4.1 | -19.6  -3.3  295  28 14   7.1   3.9
 20000 -16.8   1.8  290  27 14   7.5   4.1 | -17.4   0.7  295  25 13   7.1   3.9
 19500 -15.7   3.7  290  26 13   7.5   4.1 | -16.4   2.5  290  23 12   7.1   3.9
 19000 -14.6   5.7  285  25 13   7.3   4.0 | -15.3   4.5  290  22 11   7.3   4.0
 18500 -13.6   7.5  285  24 12   6.3   3.5 | -14.1   6.6  290  21 11   8.6   4.7
 18000 -12.6   9.3  285  23 12   6.3   3.5 | -12.9   8.8  295  21 11   8.5   4.7
 17500 -11.7  10.9  285  22 11   7.3   4.0 | -11.6  11.1  295  21 11   8.7   4.8
 17000 -10.6  12.9  285  21 11   7.5   4.1 | -10.3  13.5  295  22 11   8.7   4.8
 16500  -9.5  14.9  290  20 11   7.9   4.3 |  -9.0  15.8  295  22 11   8.6   4.7
 16000  -8.3  17.1  290  19 10   8.5   4.7 |  -7.8  18.0  295  21 11   8.3   4.6
 15500  -6.4  20.5  290  18  9   8.5   4.7 |  -6.6  20.1  290  20 10   8.4   4.6
 15000  -5.2  22.6  290  16  8   8.5   4.7 |  -4.8  23.4  290  17  9   8.9   4.9
 14500  -4.0  24.8  285  13  7   8.5   4.7 |  -3.5  25.7  290  15  8   9.1   5.0
 14000  -2.8  27.0  280  11  6   8.5   4.6 |  -2.2  28.0  290  14  7   9.1   5.0
 13500  -1.6  29.1  275   9  5   8.7   4.8 |  -0.9  30.4  290  13  7   9.2   5.1
 13000  -0.3  31.5  270   8  4   9.7   5.3 |   0.6  33.1  290  13  7  10.2   5.6
 12500   1.2  34.2  260   8  4   9.0   4.9 |   2.1  35.8  290  12  6   9.1   5.0
 12000   2.5  36.5  260   7  4   9.7   5.3 |   3.5  38.3  290  12  6   9.7   5.3
 11750   3.2  37.8  255   7  4   9.5   5.2 |   4.2  39.6  290  12  6   9.5   5.2
 11500   4.0  39.2  250   7  3   9.5   5.2 |   4.9  40.8  290  12  6   9.4   5.2
 11250   4.6  40.3  250   7  3   8.9   4.9 |   5.5  41.9  285  11  6   8.1   4.5
 11000   5.3  41.5  245   7  3   9.3   5.1 |   6.1  43.0  285  11  6   9.1   5.0
 10750   6.0  42.8  245   6  3   9.8   5.4 |   6.9  44.4  285  10  5  10.4   5.7
 10500   6.8  44.2  240   6  3   9.8   5.4 |   7.6  45.7  285  10  5  10.6   5.8
 10250   7.5  45.5  240   6  3   8.9   4.9 |   8.4  47.1  280   9  5   6.6   3.6
 10000   8.2  46.8  235   6  3   9.4   5.2 |   8.8  47.8  275   9  4   7.1   3.9
  9750   8.9  48.0  235   6  3  10.7   5.9 |   9.5  49.1  275   8  4  11.4   6.3
  9500   9.7  49.5  230   6  3  10.4   5.7 |  10.3  50.5  270   8  4  10.5   5.8
  9250  10.5  50.9  230   6  3   9.5   5.2 |  11.1  52.0  270   7  4   9.3   5.1
  9000  11.1  52.0  230   6  3   9.1   5.0 |  11.7  53.1  265   7  4   8.4   4.6
  8750  11.9  53.4  225   6  3  10.4   5.7 |  12.4  54.3  260   7  3  10.0   5.5
  8500  12.7  54.9  225   6  3  10.9   6.0 |  13.2  55.8  260   6  3  10.5   5.8
  8250  13.5  56.3  220   6  3  10.2   5.6 |  13.9  57.0  255   6  3   9.8   5.4
  8000  14.2  57.6  220   6  3  10.4   5.7 |  14.6  58.3  255   6  3   9.8   5.4
  7750  15.0  59.0  220   6  3   9.5   5.2 |  15.3  59.5  250   5  3   9.3   5.1
  7500  15.7  60.3  215   6  3  10.1   5.5 |  15.9  60.6  250   5  3   7.2   3.9
  7250  16.5  61.7  215   6  3  11.9   6.5 |  16.4  61.5  245   5  2   5.8   3.2
  7000  17.3  63.1  215   6  3  10.9   6.0 |  16.8  62.2  250   4  2   6.0   3.3
  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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