Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 271031
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0431 MDT Friday, March 27, 2015

This forecast is for Friday, March 27, 2015:

If the trigger temperature of 51.2 F/10.7 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 431 ft/min (2.2 m/s)
   Maximum height of thermals.................. 14499 ft MSL (7741 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12861 ft MSL (6103 ft AGL)
Thermal soaring outlook for Saturday 03/28..... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:51:44 / 19:16:38 MDT
Total possible sunshine........... 12 hr 24 min 54 sec (744 min 54 sec)
Altitude of sun at 13:04:20 MDT... 53.75 degrees

Upper air data from numerical model forecast valid on 03/27/2015 at 0600 MDT

Freezing level.................. 10755 ft MSL (3997 ft AGL)
Convective condensation level... 16494 ft MSL (9736 ft AGL)
Lifted condensation level....... 15163 ft MSL (8405 ft AGL)
Lifted index.................... -0.5
K index......................... +7.1

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  -57.9 -72.2   355   59   30   3.1   1.7      M     M       M      M    M
 45000  -53.6 -64.5   355   61   32  -3.0  -1.6      M     M       M      M    M
 40000  -57.1 -70.8   350   62   32  -2.3  -1.3      M     M       M      M    M
 38000  -57.2 -71.0   350   63   32   1.3   0.7      M     M       M      M    M
 36000  -56.4 -69.5   355   63   33   1.3   0.7      M     M       M      M    M
 34000  -54.6 -66.3   355   63   33   8.5   4.7      M     M       M      M    M
 32000  -48.8 -55.8   350   60   31   8.6   4.7      M     M       M      M    M
 30000  -43.7 -46.7   345   57   29   8.0   4.4   25.6  78.2     7.7      M    M
 29000  -41.3 -42.3   345   55   28   8.0   4.4   24.9  76.9     7.3      M    M
 28000  -38.9 -38.0   345   53   28   8.1   4.4   24.3  75.8     6.9      M    M
 27000  -36.5 -33.7   345   52   27   8.0   4.4   23.8  74.8     6.5      M    M
 26000  -34.0 -29.2   345   51   26   8.0   4.4   23.0  73.5     6.0      M    M
 25000  -31.6 -24.9   345   49   25   8.0   4.4   22.4  72.4     5.6      M    M
 24000  -29.2 -20.6   345   48   25   8.6   4.7   21.9  71.5     5.2      M    M
 23000  -26.6 -15.9   345   47   24   8.6   4.7   21.4  70.6     4.9      M    M
 22000  -24.0 -11.2   345   45   23   8.6   4.7   21.1  69.9     4.6      M    M
 21000  -21.4  -6.5   345   44   23   8.8   4.8   20.7  69.3     4.4      M    M
 20000  -18.8  -1.8   340   43   22   8.8   4.8   20.3  68.6     4.1      M    M
 19500  -17.5   0.5   340   42   22   8.8   4.8   20.2  68.4     4.0      M    M
 19000  -16.2   2.8   340   42   21   9.0   4.9   20.1  68.1     3.9      M    M
 18500  -14.9   5.2   340   42   21   7.6   4.2   19.8  67.7     3.7      M    M
 18000  -13.8   7.2   345   43   22   7.7   4.2   19.5  67.1     3.4      M    M
 17500  -12.6   9.3   345   44   23   7.9   4.3   19.2  66.5     3.1      M    M
 17000  -11.4  11.5   340   40   21   8.1   4.4   18.9  65.9     2.8      M    M
 16500  -10.2  13.6   340   36   19   8.1   4.4   18.6  65.5     2.6      M    M
 16000   -8.6  16.5   335   33   17   7.0   3.9   18.0  64.4     2.0      M    M
 15500   -7.6  18.3   335   31   16   6.2   3.4   17.6  63.6     1.6      M    M
 15000   -6.9  19.6   335   32   16   3.5   1.9   16.6  61.9     0.8      M    M
 14500   -6.4  20.5   335   32   17   3.6   2.0   15.6  60.2    -0.2    625  3.2
 14000   -5.9  21.4   340   32   17   3.6   2.0   14.6  58.4    -1.2    595  3.0
 13500   -5.4  22.3   340   32   17   3.3   1.8   13.7  56.6    -2.1    565  2.9
 13000   -4.8  23.4   345   32   16   6.3   3.5   12.9  55.1    -2.9    530  2.7
 12500   -3.9  25.0   345   31   16   6.2   3.4   12.3  54.1    -3.5    489  2.5
 12000   -3.0  26.6   345   31   16   7.0   3.9   11.7  53.0    -4.1    447  2.3
 11750   -2.4  27.7   345   31   16   8.3   4.6   11.6  52.8    -4.3    422  2.1
 11500   -1.8  28.8   350   31   16   7.8   4.3   11.4  52.6    -4.4    397  2.0
 11250   -1.2  29.8   350   30   16   8.6   4.7   11.3  52.3    -4.6    372  1.9
 11000   -0.5  31.1   350   30   16   9.3   5.1   11.2  52.2    -4.6    344  1.7
 10750    0.1  32.2   345   30   16   9.1   5.0   11.2  52.1    -4.7    316  1.6
 10500    0.8  33.4   345   30   16   9.3   5.1   11.1  52.1    -4.8    288  1.5
 10250    1.5  34.7   345   30   16   8.5   4.7   11.1  52.0    -4.8    261  1.3
 10000    2.1  35.8   345   31   16   8.3   4.5   11.0  51.7    -5.0    235  1.2
  9750    2.8  37.0   345   30   16   9.4   5.1   10.9  51.6    -5.0    207  1.1
  9500    3.5  38.3   340   30   16   9.6   5.3   10.9  51.6    -5.1    179  0.9
  9250    4.1  39.4   340   30   15   6.7   3.7   10.8  51.5    -5.2    152  0.8
  9000    4.5  40.1   335   27   14   4.6   2.5   10.4  50.8    -5.6    134  0.7
  8750    4.8  40.6   330   25   13   4.6   2.5   10.1  50.1    -6.0    117  0.6
  8500    5.1  41.2   320   23   12   2.8   1.6    9.6  49.3    -6.5    102  0.5
  8250    5.2  41.4   315   22   11   1.5   0.8    9.0  48.3    -7.1     90  0.5
  8000    5.3  41.5   310   21   11  -0.9  -0.5    8.3  47.0    -7.8     82  0.4
  7750    5.3  41.5   310   19   10   5.5   3.0    7.6  45.8    -8.5     73  0.4
  7500    5.5  41.9   305   18    9  -8.3  -4.5    7.2  44.9    -9.0     59  0.3
  7250    3.8  38.8   300   15    8 -28.9 -15.9    5.2  41.3   -11.1    102  0.5
  7000    2.1  35.8   300   11    6 -14.5  -8.0    3.1  37.5   -13.2    148  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           03/27/2015 at 0900 MDT          |       03/27/2015 at 1200 MDT
                                           |
K index... +9.4  LI... +276.6              | K index... +14.2  LI... +274.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.9 -74.0  360  61 32   3.1   1.7 | -59.3 -74.7  005  58 30   3.0   1.6
 45000 -54.5 -66.1  360  68 35  -1.7  -0.9 | -55.0 -67.0  360  69 35   0.9   0.5
 40000 -56.5 -69.7  355  62 32  -1.3  -0.7 | -53.7 -64.7  355  64 33   0.9   0.5
 38000 -56.4 -69.5  350  59 30   0.8   0.5 | -53.7 -64.7  350  59 31  -0.6  -0.4
 36000 -55.9 -68.6  345  55 29   0.8   0.5 | -54.1 -65.4  345  54 28  -0.6  -0.4
 34000 -53.8 -64.8  345  53 27   8.9   4.9 | -52.9 -63.2  340  51 26   7.8   4.3
 32000 -48.5 -55.3  345  53 27   8.9   4.9 | -48.1 -54.6  340  49 25   8.0   4.4
 30000 -43.3 -45.9  340  52 27   8.0   4.4 | -42.7 -44.9  340  46 24   8.2   4.5
 29000 -41.0 -41.8  340  50 26   8.0   4.4 | -40.2 -40.4  340  45 23   8.2   4.5
 28000 -38.6 -37.5  345  48 25   8.0   4.4 | -37.8 -36.0  340  43 22   8.2   4.5
 27000 -35.6 -32.1  340  46 24   7.5   4.1 | -35.4 -31.7  340  42 22   7.8   4.3
 26000 -33.4 -28.1  340  44 23   7.5   4.1 | -33.0 -27.4  335  41 21   7.9   4.3
 25000 -31.1 -24.0  340  42 21   7.5   4.1 | -30.7 -23.3  335  39 20   7.9   4.3
 24000 -28.8 -19.8  340  40 21   8.3   4.5 | -28.3 -18.9  335  38 20   8.4   4.6
 23000 -26.4 -15.5  335  39 20   8.2   4.5 | -25.8 -14.4  330  38 19   8.3   4.6
 22000 -24.0 -11.2  330  39 20   8.2   4.5 | -23.3  -9.9  325  37 19   8.3   4.6
 21000 -21.4  -6.5  330  38 19   8.9   4.9 | -20.9  -5.6  325  36 19   7.8   4.3
 20000 -18.8  -1.8  325  36 19   8.9   4.9 | -18.6  -1.5  325  36 18   7.8   4.3
 19500 -17.4   0.7  320  35 18   8.9   4.9 | -17.5   0.5  320  35 18   7.8   4.3
 19000 -16.1   3.0  320  35 18   8.9   4.9 | -16.3   2.7  320  35 18   7.8   4.3
 18500 -14.9   5.2  320  34 18   8.2   4.5 | -15.3   4.5  320  34 17   6.6   3.6
 18000 -13.6   7.5  320  34 18   8.3   4.6 | -14.3   6.3  315  33 17   6.7   3.7
 17500 -12.4   9.7  320  34 17   7.5   4.1 | -13.3   8.1  315  31 16   6.8   3.7
 17000 -11.4  11.5  320  33 17   7.3   4.0 | -12.3   9.9  310  30 16   6.8   3.8
 16500 -10.3  13.5  325  32 17   7.1   3.9 | -11.2  11.8  305  29 15   6.8   3.7
 16000  -9.3  15.3  325  32 16   6.5   3.6 | -10.3  13.5  305  28 15   6.6   3.6
 15500  -8.3  17.1  330  32 17   6.8   3.7 |  -9.3  15.3  305  27 14   6.7   3.7
 15000  -7.5  18.5  330  32 16   4.3   2.4 |  -8.3  17.1  305  26 14   6.7   3.7
 14500  -6.9  19.6  335  31 16   4.6   2.5 |  -6.8  19.8  310  25 13   6.7   3.7
 14000  -5.9  21.4  335  31 16   4.6   2.5 |  -5.9  21.4  310  25 13   6.7   3.7
 13500  -5.3  22.5  340  31 16   4.7   2.6 |  -4.9  23.2  315  24 12   6.7   3.7
 13000  -4.5  23.9  345  30 16   5.5   3.0 |  -3.9  25.0  315  23 12   6.8   3.8
 12500  -3.7  25.3  345  30 15   5.7   3.1 |  -2.9  26.8  320  23 12   6.6   3.6
 12000  -2.8  27.0  350  29 15   7.2   4.0 |  -1.8  28.8  325  22 11   7.9   4.4
 11750  -2.3  27.9  350  29 15   7.1   3.9 |  -1.2  29.8  325  22 11   7.7   4.2
 11500  -1.7  28.9  350  29 15   7.1   3.9 |  -0.7  30.7  330  22 11   7.8   4.3
 11250  -1.2  29.8  355  29 15   8.6   4.7 |  -0.1  31.8  330  22 11   8.9   4.9
 11000  -0.5  31.1  355  28 15   8.7   4.8 |   0.6  33.1  330  21 11   8.5   4.6
 10750   0.1  32.2  355  28 15   7.7   4.2 |   1.2  34.2  335  21 11   7.3   4.0
 10500   0.6  33.1  355  28 15   8.0   4.4 |   1.7  35.1  335  21 11   7.6   4.2
 10250   1.3  34.3  355  28 15   8.9   4.9 |   2.3  36.1  335  21 11   8.0   4.4
 10000   2.0  35.6  355  29 15   9.3   5.1 |   2.9  37.2  335  20 11   7.9   4.3
  9750   2.6  36.7  355  29 15   9.1   5.0 |   3.4  38.1  335  19 10   7.0   3.8
  9500   3.3  37.9  355  29 15   8.5   4.7 |   3.9  39.0  335  17  9   6.9   3.8
  9250   3.9  39.0  350  28 14   7.0   3.8 |   4.4  39.9  335  15  8   7.2   3.9
  9000   4.4  39.9  350  26 14   6.7   3.7 |   4.9  40.8  330  13  7   7.2   3.9
  8750   4.8  40.6  345  25 13   5.0   2.7 |   5.4  41.7  330  11  6   8.7   4.8
  8500   5.1  41.2  340  23 12   2.8   1.5 |   6.1  43.0  325   9  5  10.1   5.6
  8250   5.2  41.4  335  21 11   2.6   1.4 |   6.8  44.2  325   8  4  10.1   5.5
  8000   5.4  41.7  330  19 10   2.6   1.4 |   7.6  45.7  320   7  4  10.3   5.6
  7750   5.6  42.1  325  17  9   2.5   1.4 |   8.3  46.9  320   7  3   9.9   5.4
  7500   5.6  42.1  320  15  8  -0.0  -0.0 |   9.0  48.2  320   6  3   9.4   5.2
  7250   5.5  41.9  320  12  6  -2.0  -1.1 |   9.7  49.5  320   6  3   9.3   5.1
  7000   5.3  41.5  315  10  5  -0.4  -0.2 |  10.4  50.7  325   6  3   9.4   5.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           03/27/2015 at 1500 MDT          |       03/27/2015 at 1800 MDT
                                           |
K index... +23.5  LI... +271.8             | K index... +20.7  LI... +270.9
CAPE... +210.1  CIN... -2.3                | CAPE... +345.7  CIN... -11.4
                                           |
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 -60.0 -76.0  005  54 28   3.0   1.7 | -59.9 -75.8  360  52 27   3.4   1.9
 45000 -55.4 -67.7  355  63 32   1.8   1.0 | -54.9 -66.8  360  58 30   2.7   1.5
 40000 -52.7 -62.9  350  66 34   1.8   1.0 | -50.9 -59.6  350  66 34   2.6   1.4
 38000 -52.7 -62.9  345  59 30  -0.7  -0.4 | -51.0 -59.8  345  60 31  -1.5  -0.8
 36000 -53.1 -63.6  340  49 25  -0.7  -0.4 | -51.8 -61.2  340  52 27  -1.5  -0.8
 34000 -51.9 -61.4  335  42 22   7.6   4.1 | -50.6 -59.1  335  43 22   7.2   3.9
 32000 -47.3 -53.1  335  40 21   7.6   4.2 | -46.3 -51.3  330  37 19   7.2   3.9
 30000 -42.1 -43.8  335  37 19   7.9   4.3 | -41.9 -43.4  325  33 17   7.5   4.1
 29000 -39.7 -39.5  335  37 19   7.9   4.3 | -39.7 -39.5  325  34 17   7.5   4.1
 28000 -37.4 -35.3  335  36 18   7.9   4.3 | -37.4 -35.3  325  34 17   7.5   4.1
 27000 -35.0 -31.0  335  35 18   7.7   4.2 | -35.2 -31.4  320  34 18   7.8   4.3
 26000 -32.7 -26.9  330  35 18   7.7   4.2 | -32.8 -27.0  320  35 18   7.8   4.3
 25000 -30.4 -22.7  330  35 18   7.7   4.2 | -30.5 -22.9  320  36 18   7.8   4.3
 24000 -28.1 -18.6  330  35 18   8.4   4.6 | -28.1 -18.6  320  36 19   7.7   4.2
 23000 -25.6 -14.1  325  35 18   8.4   4.6 | -25.8 -14.4  320  35 18   7.8   4.3
 22000 -23.1  -9.6  325  36 19   8.4   4.6 | -23.5 -10.3  320  35 18   7.8   4.3
 21000 -20.7  -5.3  320  36 18   7.3   4.0 | -21.2  -6.2  325  35 18   7.7   4.2
 20000 -18.5  -1.3  320  34 18   7.4   4.0 | -18.9  -2.0  325  35 18   7.7   4.2
 19500 -17.5   0.5  325  34 17   7.4   4.0 | -17.8  -0.0  325  35 18   7.7   4.2
 19000 -16.4   2.5  325  33 17   7.3   4.0 | -16.7   1.9  325  35 18   7.8   4.3
 18500 -15.4   4.3  325  32 16   5.9   3.3 | -15.6   3.9  325  35 18   7.4   4.0
 18000 -14.5   5.9  325  31 16   6.1   3.3 | -14.5   5.9  325  33 17   7.4   4.1
 17500 -13.6   7.5  325  29 15   6.8   3.7 | -13.4   7.9  325  32 17   7.0   3.9
 17000 -12.6   9.3  325  28 15   7.1   3.9 | -12.4   9.7  330  32 17   6.8   3.7
 16500 -11.5  11.3  325  27 14   7.2   3.9 | -10.9  12.4  335  33 17   7.0   3.9
 16000 -10.4  13.3  325  27 14   7.5   4.1 |  -9.8  14.4  335  32 17   7.1   3.9
 15500  -9.4  15.1  325  26 14   7.5   4.1 |  -8.8  16.2  340  32 17   7.5   4.1
 15000  -7.7  18.1  325  26 13   7.4   4.1 |  -7.6  18.3  340  32 16   8.0   4.4
 14500  -6.6  20.1  325  26 13   7.5   4.1 |  -6.4  20.5  340  31 16   8.1   4.4
 14000  -5.5  22.1  325  25 13   7.6   4.2 |  -5.2  22.6  340  30 16   8.5   4.7
 13500  -4.4  24.1  325  25 13   7.6   4.2 |  -3.9  25.0  340  30 15   8.6   4.7
 13000  -3.3  26.1  325  24 12   7.8   4.3 |  -2.6  27.3  340  28 15   9.3   5.1
 12500  -2.2  28.0  320  22 11   8.0   4.4 |  -1.3  29.7  335  27 14   9.0   4.9
 12000  -1.0  30.2  320  19 10   8.7   4.8 |   0.0  32.0  330  25 13   9.1   5.0
 11750  -0.4  31.3  315  17  9   8.7   4.8 |   0.7  33.3  330  25 13   9.0   4.9
 11500   0.3  32.5  315  15  8   8.7   4.8 |   1.3  34.3  330  24 12   9.1   5.0
 11250   0.9  33.6  310  13  7   8.9   4.9 |   2.0  35.6  325  23 12   8.7   4.8
 11000   1.6  34.9  310  12  6   9.6   5.3 |   2.6  36.7  325  21 11   8.4   4.6
 10750   2.3  36.1  305  11  6  10.0   5.5 |   3.2  37.8  325  20 10   8.5   4.7
 10500   3.0  37.4  305  10  5   9.9   5.4 |   3.8  38.8  325  18  9   8.6   4.7
 10250   3.7  38.7  305   9  4   9.2   5.1 |   4.4  39.9  325  17  9   7.7   4.2
 10000   4.4  39.9  305   8  4   9.5   5.2 |   4.9  40.8  320  15  8   7.9   4.3
  9750   5.2  41.4  305   8  4  10.6   5.8 |   5.6  42.1  325  13  7   9.1   5.0
  9500   5.9  42.6  305   8  4  10.3   5.6 |   6.2  43.2  325  12  6   9.1   5.0
  9250   6.7  44.1  305   7  4   9.3   5.1 |   6.9  44.4  325  11  5   8.8   4.8
  9000   7.3  45.1  300   7  4   8.9   4.9 |   7.5  45.5  325  10  5   8.6   4.7
  8750   8.0  46.4  300   7  4  10.3   5.6 |   8.2  46.8  330   9  5  10.0   5.5
  8500   8.9  48.0  305   6  3  10.9   6.0 |   8.9  48.0  335   8  4  10.5   5.8
  8250   9.6  49.3  305   6  3  10.3   5.6 |   9.7  49.5  335   8  4   9.7   5.3
  8000  10.4  50.7  305   6  3  10.5   5.8 |  10.4  50.7  335   8  4   9.5   5.2
  7750  11.2  52.2  305   6  3   9.9   5.4 |  11.1  52.0  335   8  4  10.2   5.6
  7500  11.9  53.4  305   5  3   9.7   5.3 |  11.8  53.2  340   8  4   7.7   4.2
  7250  12.6  54.7  310   5  3  10.3   5.7 |  12.2  54.0  340   7  4   4.8   2.6
  7000  13.3  55.9  310   5  3   9.8   5.4 |  12.6  54.7  340   7  3   7.1   3.9
  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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