Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 271010
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0410 MDT Friday, May 27, 2016

This forecast is for Friday, May 27, 2016:

If the trigger temperature of 49.3 F/9.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 11811 ft MSL (4640 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... 1645 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9828 ft MSL (2657 ft AGL)
Thermal soaring outlook for Saturday 05/28..... Good

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

Remarks...

Sunrise/Sunset.................... 05:37:38 / 20:14:41 MDT
Total possible sunshine........... 14 hr 37 min 3 sec (877 min 3 sec)
Altitude of sun at 12:56:21 MDT... 72.49 degrees

Upper air data from numerical model forecast valid on 05/27/2016 at 0600 MDT

Freezing level.................. 9571 ft MSL (2400 ft AGL)
Convective condensation level... 10312 ft MSL (3141 ft AGL)
Lifted condensation level....... 11261 ft MSL (4090 ft AGL)
Lifted index.................... +0.6
K index......................... +23.5

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  -53.2 -63.8   200   23   12   0.8   0.5      M     M       M      M    M
 45000  -52.0 -61.6   210   26   14   0.7   0.4      M     M       M      M    M
 40000  -51.1 -60.0   220   18    9   0.6   0.3      M     M       M      M    M
 38000  -50.9 -59.6   225   13    7   0.1   0.1      M     M       M      M    M
 36000  -50.8 -59.4   230    7    4   0.1   0.1      M     M       M      M    M
 34000  -50.4 -58.7   315    1    1   4.9   2.7      M     M       M      M    M
 32000  -47.8 -54.0   025   12    6   4.3   2.4      M     M       M      M    M
 30000  -44.8 -48.6   030   21   11   9.9   5.4   25.1  77.2    11.1      M    M
 29000  -42.0 -43.6   030   21   11   9.4   5.1   24.8  76.7    11.1      M    M
 28000  -39.2 -38.6   030   20   10   9.4   5.1   24.7  76.4    11.1      M    M
 27000  -35.7 -32.3   030   19   10   8.9   4.9   24.6  76.3    11.2      M    M
 26000  -33.1 -27.6   030   18    9   8.6   4.7   24.1  75.3    10.9      M    M
 25000  -30.6 -23.1   025   17    9   8.6   4.7   23.7  74.6    10.6      M    M
 24000  -28.0 -18.4   025   16    8   8.4   4.6   23.3  74.0    10.5      M    M
 23000  -25.7 -14.3   025   19   10   7.5   4.1   22.5  72.5     9.9      M    M
 22000  -23.5 -10.3   025   23   12   7.5   4.1   21.7  71.1     9.3      M    M
 21000  -21.3  -6.3   025   27   14   7.1   3.9   21.0  69.8     8.8      M    M
 20000  -19.3  -2.7   025   30   16   6.9   3.8   19.9  67.8     7.9      M    M
 19500  -18.3  -0.9   020   32   17   6.9   3.8   19.4  66.9     7.5      M    M
 19000  -17.2   1.0   020   34   18   6.9   3.8   18.9  66.1     7.1      M    M
 18500  -16.2   2.8   020   36   19   6.9   3.8   18.5  65.3     6.7      M    M
 18000  -15.2   4.6   020   37   19   6.8   3.7   18.0  64.4     6.3      M    M
 17500  -14.2   6.4   020   38   19   6.9   3.8   17.5  63.5     5.9      M    M
 17000  -13.3   8.1   015   38   20   6.1   3.3   17.0  62.5     5.4      M    M
 16500  -12.4   9.7   015   39   20   6.1   3.3   16.3  61.4     4.8      M    M
 16000  -11.5  11.3   015   40   20   6.1   3.3   15.8  60.4     4.3      M    M
 15500  -10.6  12.9   010   40   20   6.0   3.3   15.1  59.2     3.7      M    M
 15000   -9.7  14.5   010   40   21   6.2   3.4   14.5  58.1     3.2      M    M
 14500   -8.8  16.2   010   40   20   6.8   3.7   14.0  57.2     2.7      M    M
 14000   -7.8  18.0   005   40   20   6.8   3.7   13.5  56.3     2.2      M    M
 13500   -6.8  19.8   005   39   20   6.7   3.7   13.0  55.4     1.7      M    M
 13000   -5.9  21.4   005   39   20   6.7   3.7   12.5  54.6     1.2      M    M
 12500   -4.9  23.2   360   39   20   7.3   4.0   12.1  53.8     0.8      M    M
 12000   -3.9  25.0   360   38   20   6.5   3.6   11.7  53.0     0.3      M    M
 11750   -3.4  25.9   360   38   19   5.8   3.2   11.4  52.5     0.1      M    M
 11500   -3.0  26.6   360   37   19   5.2   2.8   11.0  51.9    -0.3    368  1.9
 11250   -2.6  27.3   360   37   19   5.1   2.8   10.7  51.2    -0.6    349  1.8
 11000   -2.3  27.9   360   36   19   5.3   2.9   10.3  50.6    -1.0    331  1.7
 10750   -1.9  28.6   355   36   18   5.1   2.8   10.0  49.9    -1.4    312  1.6
 10500   -1.5  29.3   355   35   18   4.7   2.6    9.6  49.2    -1.7    294  1.5
 10250   -0.9  30.4   355   34   18   4.5   2.5    8.8  47.8    -2.5    259  1.3
 10000   -0.5  31.1   355   34   17   5.6   3.1    8.4  47.1    -2.9    241  1.2
  9750   -0.1  31.8   355   34   17   5.7   3.1    8.1  46.6    -3.2    221  1.1
  9500    0.3  32.5   355   32   17   4.7   2.6    7.7  45.9    -3.6    203  1.0
  9250    0.6  33.1   355   31   16   4.9   2.7    7.4  45.3    -4.0    185  0.9
  9000    1.0  33.8   350   30   15   7.6   4.2    7.1  44.7    -4.3    166  0.8
  8750    1.7  35.1   350   28   14   8.9   4.9    7.0  44.6    -4.4    139  0.7
  8500    2.2  36.0   350   26   13   7.7   4.2    6.9  44.4    -4.6    114  0.6
  8250    2.8  37.0   350   23   12   8.0   4.4    6.7  44.1    -4.8     89  0.5
  8000    3.4  38.1   345   21   11   7.8   4.3    6.6  43.9    -4.9     65  0.3
  7750    4.0  39.2   345   18    9   8.4   4.6    6.5  43.7    -5.1     41  0.2
  7500    4.6  40.3   345   14    7   9.6   5.3    6.4  43.6    -5.2     14  0.1
  7250    5.3  41.5   340   10    5   7.5   4.1    6.4  43.5    -5.3      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           05/27/2016 at 0900 MDT          |       05/27/2016 at 1200 MDT
                                           |
K index... +20.8  LI... +274.4             | K index... +18.8  LI... +273.8
CAPE... +12.7  CIN... M                    | CAPE... +23.1  CIN... -42.5
                                           |
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 -54.3 -65.7  190  25 13   1.5   0.9 | -54.8 -66.6  195  24 12   1.4   0.8
 45000 -52.0 -61.6  210  25 13   0.5   0.3 | -52.7 -62.9  210  21 11   0.6   0.4
 40000 -51.9 -61.4  205  11  6   0.0   0.0 | -52.3 -62.1  210  17  9   0.3   0.1
 38000 -51.7 -61.1  210   4  2   0.6   0.3 | -52.2 -62.0  220  11  6  -0.1  -0.1
 36000 -51.4 -60.5  005   3  1   0.6   0.3 | -52.3 -62.1  285   3  2  -0.1  -0.1
 34000 -50.6 -59.1  015   9  5   5.7   3.1 | -51.8 -61.2  360  10  5   6.2   3.4
 32000 -47.5 -53.5  020  14  7   5.2   2.9 | -48.4 -55.1  355  16  8   5.7   3.1
 30000 -44.0 -47.2  020  18  9   8.8   4.8 | -44.5 -48.1  355  21 11  10.2   5.6
 29000 -41.5 -42.7  010  19 10   8.6   4.7 | -40.8 -41.4  350  22 11   9.9   5.4
 28000 -38.9 -38.0  360  21 11   8.6   4.7 | -37.9 -36.2  350  22 12   9.9   5.4
 27000 -36.3 -33.3  355  23 12   8.6   4.7 | -35.0 -31.0  345  23 12   8.9   4.9
 26000 -33.0 -27.4  350  23 12   8.9   4.9 | -32.4 -26.3  340  23 12   8.5   4.7
 25000 -30.4 -22.7  355  23 12   8.9   4.9 | -29.9 -21.8  335  24 12   8.5   4.7
 24000 -27.7 -17.9  355  23 12   8.6   4.7 | -27.3 -17.1  330  24 12   8.2   4.5
 23000 -25.3 -13.5  360  24 12   8.0   4.4 | -25.1 -13.2  335  24 12   7.4   4.1
 22000 -23.0  -9.4  005  25 13   8.0   4.4 | -22.9  -9.2  340  24 12   7.4   4.1
 21000 -20.6  -5.1  010  27 14   7.2   4.0 | -20.8  -5.4  345  24 13   7.1   3.9
 20000 -18.6  -1.5  010  30 16   6.8   3.7 | -18.7  -1.7  350  26 13   7.0   3.9
 19500 -17.6   0.3  010  32 17   6.8   3.7 | -17.7   0.1  355  27 14   7.0   3.9
 19000 -16.6   2.1  015  34 17   6.8   3.7 | -16.6   2.1  360  27 14   7.0   3.9
 18500 -15.6   3.9  015  36 18   6.6   3.6 | -15.6   3.9  360  28 15   7.0   3.8
 18000 -14.7   5.5  015  38 19   6.2   3.4 | -14.6   5.7  360  30 15   6.8   3.7
 17500 -13.8   7.2  015  39 20   6.2   3.4 | -13.6   7.5  005  32 16   6.8   3.7
 17000 -12.9   8.8  015  41 21   5.7   3.2 | -12.6   9.3  005  34 17   7.1   3.9
 16500 -12.0  10.4  010  42 22   5.8   3.2 | -11.5  11.3  360  36 18   7.1   3.9
 16000 -11.2  11.8  010  43 22   6.0   3.3 | -10.5  13.1  360  37 19   6.0   3.3
 15500 -10.3  13.5  010  44 23   6.1   3.3 |  -9.7  14.5  355  38 20   5.2   2.8
 15000  -9.4  15.1  005  44 23   6.1   3.3 |  -9.0  15.8  355  39 20   5.2   2.9
 14500  -8.5  16.7  005  45 23   6.1   3.3 |  -7.7  18.1  350  41 21   5.7   3.1
 14000  -7.6  18.3  360  45 23   6.1   3.3 |  -6.9  19.6  350  41 21   5.9   3.2
 13500  -6.8  19.8  360  46 23   5.8   3.2 |  -6.0  21.2  350  42 22   6.0   3.3
 13000  -5.9  21.4  360  46 24   5.8   3.2 |  -5.1  22.8  350  43 22   6.1   3.4
 12500  -5.0  23.0  360  46 24   6.4   3.5 |  -4.2  24.4  350  43 22   6.3   3.4
 12000  -4.2  24.4  355  46 24   5.3   2.9 |  -3.4  25.9  350  44 22   5.4   3.0
 11750  -3.8  25.2  355  46 24   5.4   3.0 |  -3.0  26.6  350  44 23   5.2   2.9
 11500  -3.4  25.9  355  46 24   6.0   3.3 |  -2.6  27.3  350  44 23   5.2   2.9
 11250  -2.9  26.8  355  46 24   6.2   3.4 |  -2.2  28.0  350  44 23   5.1   2.8
 11000  -2.5  27.5  355  46 24   5.3   2.9 |  -1.9  28.6  350  45 23   5.8   3.2
 10750  -2.2  28.0  355  45 23   5.1   2.8 |  -1.4  29.5  350  44 23   6.8   3.7
 10500  -1.7  28.9  355  45 23   6.1   3.4 |  -0.9  30.4  350  42 22   6.9   3.8
 10250  -0.9  30.4  355  44 23   5.8   3.2 |  -0.5  31.1  350  40 21   6.7   3.7
 10000  -0.4  31.3  355  44 22   7.6   4.2 |   0.0  32.0  350  39 20   7.8   4.3
  9750   0.2  32.4  355  43 22   7.5   4.1 |   0.6  33.1  350  37 19   9.6   5.3
  9500   0.6  33.1  350  42 21   5.7   3.1 |   1.4  34.5  350  36 18   9.9   5.4
  9250   1.1  34.0  350  40 21   6.1   3.3 |   2.1  35.8  350  35 18   9.8   5.4
  9000   1.5  34.7  350  39 20   7.0   3.8 |   2.8  37.0  350  34 17   9.9   5.4
  8750   2.1  35.8  350  37 19   8.9   4.9 |   3.5  38.3  350  33 17  10.4   5.7
  8500   2.7  36.9  345  35 18   9.3   5.1 |   4.3  39.7  350  33 17  10.7   5.9
  8250   3.4  38.1  345  33 17   9.4   5.2 |   5.1  41.2  350  32 17  10.6   5.8
  8000   4.1  39.4  345  31 16   9.8   5.4 |   5.9  42.6  350  32 16  10.9   6.0
  7750   4.9  40.8  340  28 15  12.4   6.8 |   6.7  44.1  350  30 16  10.6   5.8
  7500   6.0  42.8  340  23 12  16.6   9.1 |   7.4  45.3  350  29 15   9.1   5.0
  7250   7.0  44.6  340  19 10   9.1   5.0 |   8.1  46.6  350  27 14  12.1   6.7
  7000     M     M    M   M  M     M     M |   9.3  48.7  350  25 13  20.0  11.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/27/2016 at 1500 MDT          |       05/27/2016 at 1800 MDT
                                           |
K index... +17.7  LI... +274.5             | K index... +23.1  LI... +273.2
CAPE... 0.0  CIN... M                      | CAPE... +3.1  CIN... -46.1
                                           |
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 -54.1 -65.4  200  22 11   1.1   0.6 | -54.3 -65.7  200  23 12   0.8   0.5
 45000 -52.6 -62.7  215  19 10  -0.3  -0.2 | -53.1 -63.6  205  16  8  -0.2  -0.1
 40000 -52.9 -63.2  240  17  9  -0.2  -0.1 | -53.3 -63.9  255  11  6  -0.1  -0.1
 38000 -52.9 -63.2  255  15  8  -0.1  -0.1 | -53.5 -64.3  280  14  7  -0.7  -0.4
 36000 -53.0 -63.4  285  14  7  -0.1  -0.1 | -54.0 -65.2  295  19 10  -0.7  -0.4
 34000 -52.4 -62.3  310  17  9   6.9   3.8 | -53.3 -63.9  300  23 12   8.1   4.5
 32000 -48.5 -55.3  325  22 11   6.5   3.5 | -48.5 -55.3  300  24 12   8.0   4.4
 30000 -43.6 -46.5  330  26 13   9.6   5.3 | -42.7 -44.9  300  24 12   9.6   5.3
 29000 -40.7 -41.3  335  25 13   9.6   5.3 | -39.8 -39.6  300  23 12   9.6   5.3
 28000 -37.8 -36.0  335  24 13   9.6   5.3 | -37.0 -34.6  305  22 11   9.6   5.3
 27000 -35.0 -31.0  340  24 12   8.9   4.9 | -34.2 -29.6  305  21 11   8.4   4.6
 26000 -32.4 -26.3  345  24 13   8.8   4.8 | -31.7 -25.1  305  21 11   8.5   4.6
 25000 -29.8 -21.6  350  25 13   8.8   4.8 | -29.1 -20.4  310  21 11   8.5   4.7
 24000 -27.1 -16.8  355  26 14   8.2   4.5 | -26.6 -15.9  315  20 10   8.1   4.4
 23000 -24.9 -12.8  355  28 15   7.4   4.1 | -24.3 -11.7  315  21 11   7.8   4.3
 22000 -22.7  -8.9  355  30 16   7.4   4.1 | -22.0  -7.6  315  21 11   7.8   4.3
 21000 -20.5  -4.9  355  32 17   7.4   4.1 | -19.7  -3.5  320  22 11   7.2   4.0
 20000 -18.4  -1.1  355  33 17   7.4   4.1 | -17.6   0.3  325  23 12   7.2   4.0
 19500 -17.3   0.9  355  33 17   7.4   4.1 | -16.5   2.3  325  24 12   7.2   4.0
 19000 -16.2   2.8  355  33 17   7.4   4.1 | -15.5   4.1  330  25 13   7.2   4.0
 18500 -15.1   4.8  355  33 17   7.4   4.1 | -14.4   6.1  330  25 13   6.8   3.7
 18000 -14.0   6.8  350  32 16   7.5   4.1 | -13.5   7.7  330  26 13   6.5   3.6
 17500 -12.9   8.8  350  31 16   7.5   4.1 | -12.5   9.5  330  27 14   6.5   3.6
 17000 -11.8  10.8  345  31 16   7.6   4.2 | -11.6  11.1  330  27 14   7.0   3.8
 16500 -10.7  12.7  340  31 16   7.6   4.2 | -10.5  13.1  330  28 15   7.0   3.8
 16000  -9.6  14.7  340  31 16   6.8   3.7 |  -9.5  14.9  330  29 15   6.7   3.7
 15500  -8.6  16.5  340  32 17   6.3   3.5 |  -8.6  16.5  330  29 15   6.7   3.7
 15000  -7.7  18.1  340  33 17   6.0   3.3 |  -7.1  19.2  330  30 15   6.6   3.6
 14500  -6.5  20.3  340  36 18   5.3   2.9 |  -6.2  20.8  335  30 16   6.6   3.6
 14000  -5.7  21.7  340  37 19   5.1   2.8 |  -5.2  22.6  335  30 16   6.5   3.6
 13500  -5.0  23.0  340  39 20   5.0   2.8 |  -4.3  24.3  335  31 16   6.5   3.5
 13000  -4.3  24.3  340  40 21   5.3   2.9 |  -3.3  26.1  340  31 16   6.4   3.5
 12500  -3.4  25.9  345  41 21   5.7   3.1 |  -2.4  27.7  340  30 16   6.3   3.5
 12000  -2.6  27.3  345  41 21   5.4   3.0 |  -1.6  29.1  340  30 15   5.6   3.1
 11750  -2.2  28.0  345  41 21   6.2   3.4 |  -1.1  30.0  340  29 15   6.1   3.4
 11500  -1.7  28.9  345  41 21   6.2   3.4 |  -0.7  30.7  340  29 15   6.1   3.4
 11250  -1.3  29.7  345  41 21   6.1   3.3 |  -0.3  31.5  340  28 15   5.6   3.1
 11000  -0.8  30.6  345  41 21   6.3   3.4 |   0.1  32.2  340  28 15   5.4   3.0
 10750  -0.3  31.5  350  40 21   6.6   3.6 |   0.5  32.9  340  28 14   5.8   3.2
 10500   0.1  32.2  350  39 20   6.6   3.6 |   0.9  33.6  340  28 14   5.8   3.2
 10250   0.6  33.1  350  38 20   6.6   3.6 |   1.4  34.5  340  28 14   5.7   3.1
 10000   1.1  34.0  350  37 19   6.8   3.8 |   1.8  35.2  345  27 14   5.9   3.2
  9750   1.6  34.9  350  34 18   8.6   4.7 |   2.2  36.0  345  25 13   7.1   3.9
  9500   2.3  36.1  350  33 17   9.7   5.3 |   2.7  36.9  345  24 12   7.7   4.2
  9250   2.9  37.2  350  31 16   9.4   5.2 |   3.3  37.9  345  22 12   7.6   4.2
  9000   3.6  38.5  350  29 15   9.7   5.3 |   3.8  38.8  345  21 11   8.5   4.7
  8750   4.3  39.7  350  29 15  10.3   5.7 |   4.5  40.1  345  21 11   9.8   5.4
  8500   5.1  41.2  350  28 15  10.7   5.8 |   5.2  41.4  345  21 11  10.2   5.6
  8250   5.9  42.6  350  28 14  10.7   5.8 |   6.0  42.8  345  21 11  10.2   5.6
  8000   6.7  44.1  350  27 14  11.5   6.3 |   6.8  44.2  345  20 10  10.9   6.0
  7750   7.6  45.7  350  26 14  10.8   5.9 |   7.6  45.7  350  19 10  10.0   5.5
  7500   8.3  46.9  355  25 13   8.4   4.6 |   8.2  46.8  350  19 10   8.6   4.7
  7250   9.0  48.2  355  24 12  11.8   6.5 |   8.9  48.0  350  18  9   9.2   5.1
  7000  10.1  50.2  355  22 11  20.1  11.0 |   9.6  49.3  350  17  9  10.4   5.7
  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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