Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 081106
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0406 MST Monday, February 8, 2016

This forecast is for Monday, February 8, 2016:

If the trigger temperature of 43.9 F/6.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 338 ft/min (1.7 m/s)
   Maximum height of thermals.................. 11216 ft MSL (4045 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... 1345 MST
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................. 9022 ft MSL (1852 ft AGL)
Thermal soaring outlook for Tuesday 02/09...... Fair

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

Remarks...

Sunrise/Sunset.................... 06:58:38 / 17:26:46 MST
Total possible sunshine........... 10 hr 28 min 7 sec (628 min 7 sec)
Altitude of sun at 12:13:02 MST... 36.11 degrees

Upper air data from numerical model forecast valid on 02/08/2016 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 18124 ft MSL (10953 ft AGL)
Lifted condensation level....... 14139 ft MSL (6969 ft AGL)
Lifted index.................... +8.8
K index......................... -0.2

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  -56.6 -69.9   335   41   21   0.4   0.2      M     M       M      M    M
 45000  -56.0 -68.8   335   55   28  -0.8  -0.4      M     M       M      M    M
 40000  -62.8 -81.0   340   79   41  -4.5  -2.5      M     M       M      M    M
 38000  -62.3 -80.1   340   78   40   5.2   2.9      M     M       M      M    M
 36000  -59.1 -74.4   340   70   36   5.2   2.9      M     M       M      M    M
 34000  -55.4 -67.7   340   65   33   8.9   4.9      M     M       M      M    M
 32000  -50.0 -58.0   340   65   33   9.0   5.0      M     M       M      M    M
 30000  -44.7 -48.5   345   67   34   8.5   4.7   25.5  77.9    14.4      M    M
 29000  -42.1 -43.8   345   69   36   8.5   4.6   24.9  76.8    14.1      M    M
 28000  -39.6 -39.3   345   72   37   8.5   4.6   24.5  76.0    14.0      M    M
 27000  -37.1 -34.8   350   74   38   8.3   4.5   24.1  75.4    13.8      M    M
 26000  -34.6 -30.3   350   74   38   8.2   4.5   23.4  74.1    13.5      M    M
 25000  -31.5 -24.7   350   73   38   8.2   4.5   22.7  72.9    13.1      M    M
 24000  -29.1 -20.4   350   73   38   7.4   4.0   22.2  71.9    12.8      M    M
 23000  -26.9 -16.4   355   72   37   7.4   4.1   21.2  70.2    12.2      M    M
 22000  -24.7 -12.5   355   71   37   7.4   4.1   20.5  68.8    11.6      M    M
 21000  -22.4  -8.3   355   70   36   7.6   4.2   19.7  67.5    11.1      M    M
 20000  -20.2  -4.4   355   68   35   7.6   4.2   18.9  66.0    10.5      M    M
 19500  -19.0  -2.2   350   68   35   7.6   4.2   18.6  65.4    10.3      M    M
 19000  -17.9  -0.2   350   67   34   7.7   4.2   18.2  64.8    10.1      M    M
 18500  -16.8   1.8   350   66   34   7.5   4.1   17.9  64.2     9.8      M    M
 18000  -15.7   3.7   350   67   34   7.5   4.1   17.5  63.5     9.5      M    M
 17500  -14.5   5.9   350   67   34   7.4   4.1   17.1  62.8     9.2      M    M
 17000  -13.5   7.7   350   66   34   7.4   4.1   16.7  62.1     8.9      M    M
 16500  -12.4   9.7   345   66   34   7.3   4.0   16.3  61.4     8.6      M    M
 16000  -11.3  11.7   345   66   34   6.8   3.7   15.9  60.5     8.2      M    M
 15500  -10.3  13.5   345   65   34   7.0   3.8   15.4  59.7     7.8      M    M
 15000   -9.4  15.1   345   65   33   5.4   2.9   14.8  58.6     7.3      M    M
 14500   -8.6  16.5   345   64   33   5.7   3.1   14.1  57.4     6.6      M    M
 14000   -7.9  17.8   345   63   33   3.3   1.8   13.3  55.9     5.9      M    M
 13500   -7.5  18.5   340   63   32   3.0   1.6   12.2  53.9     4.9      M    M
 13000   -7.1  19.2   340   62   32   2.4   1.3   11.1  52.0     3.8      M    M
 12500   -6.8  19.8   340   61   31   2.3   1.3    9.9  49.8     2.7      M    M
 12000   -6.5  20.3   340   59   30   2.8   1.5    8.7  47.7     1.6      M    M
 11750   -6.2  20.8   345   58   30   3.8   2.1    8.2  46.7     1.1      M    M
 11500   -6.0  21.2   345   57   29   3.7   2.0    7.7  45.9     0.7      M    M
 11250   -5.7  21.7   345   56   29   4.0   2.2    7.2  45.0     0.2      M    M
 11000   -5.3  22.5   345   55   28   6.2   3.4    6.9  44.4    -0.2    330  1.7
 10750   -4.8  23.4   345   54   28   7.1   3.9    6.7  44.0    -0.4    307  1.6
 10500   -4.3  24.3   345   54   28   6.3   3.5    6.4  43.5    -0.6    285  1.4
 10250   -3.8  25.2   345   54   28   6.5   3.6    6.2  43.1    -0.9    263  1.3
 10000   -3.3  26.1   345   53   27   6.9   3.8    5.9  42.7    -1.1    241  1.2
  9750   -2.4  27.7   340   51   26   4.6   2.5    5.3  41.6    -1.7    200  1.0
  9500   -2.1  28.2   340   50   26   3.0   1.6    4.9  40.8    -2.1    183  0.9
  9250   -2.0  28.4   340   48   24   1.5   0.8    4.3  39.7    -2.7    171  0.9
  9000   -1.9  28.6   340   45   23   1.4   0.8    3.7  38.6    -3.3    161  0.8
  8750   -1.8  28.8   335   41   21  -0.2  -0.1    3.0  37.4    -4.0    152  0.8
  8500   -1.9  28.6   335   37   19  -1.4  -0.8    2.1  35.9    -4.8    147  0.7
  8250   -2.0  28.4   335   34   17  -1.9  -1.0    1.3  34.3    -5.7    143  0.7
  8000   -2.1  28.2   330   30   16   0.2   0.1    0.4  32.8    -6.6    139  0.7
  7750   -2.4  27.7   330   27   14 -11.9  -6.6   -0.5  31.1    -7.5    138  0.7
  7500   -4.2  24.4   330   20   10 -36.2 -19.8   -3.1  26.4   -10.2    187  1.0
  7250   -5.7  21.7   320   10    5  22.4  12.3   -5.3  22.4   -12.4    224  1.1
  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 * * * * * *

           02/08/2016 at 0800 MST          |       02/08/2016 at 1100 MST
                                           |
K index... +1.6  LI... +277.7              | K index... +2.4  LI... +278.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
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 -56.7 -70.1  340  42 22   0.6   0.3 | -57.6 -71.7  340  45 23   1.0   0.5
 45000 -55.8 -68.4  335  53 27  -1.0  -0.6 | -56.1 -69.0  335  55 28  -1.3  -0.7
 40000 -61.6 -78.9  350  72 37  -3.8  -2.1 | -63.2 -81.8  350  72 37  -4.6  -2.5
 38000 -61.3 -78.3  355  79 41   3.6   2.0 | -62.3 -80.1  355  76 39   5.6   3.1
 36000 -59.1 -74.4  360  85 44   3.6   2.0 | -58.9 -74.0  360  79 41   5.6   3.1
 34000 -56.0 -68.8  360  83 43   8.7   4.8 | -54.9 -66.8  005  81 42   8.7   4.8
 32000 -50.7 -59.3  345  60 31   8.9   4.9 | -49.7 -57.5  005  79 41   8.8   4.8
 30000 -45.3 -49.5  325  48 25   9.6   5.2 | -44.3 -47.7  005  73 38   9.5   5.2
 29000 -42.4 -44.3  325  47 24   9.6   5.2 | -41.4 -42.5  360  66 34   9.5   5.2
 28000 -39.5 -39.1  325  45 23   9.6   5.3 | -38.6 -37.5  350  59 30   9.5   5.2
 27000 -36.7 -34.1  325  45 23   8.8   4.8 | -35.8 -32.4  345  54 28   9.1   5.0
 26000 -34.1 -29.4  335  49 25   8.6   4.7 | -32.4 -26.3  340  52 27   9.1   5.0
 25000 -30.9 -23.6  345  55 29   8.6   4.7 | -29.6 -21.3  340  51 26   9.1   5.0
 24000 -28.4 -19.1  350  60 31   7.3   4.0 | -27.1 -16.8  335  48 25   7.4   4.0
 23000 -26.1 -15.0  350  60 31   7.5   4.1 | -24.8 -12.6  330  42 21   7.5   4.1
 22000 -23.9 -11.0  350  60 31   7.5   4.1 | -22.5  -8.5  325  35 18   7.5   4.1
 21000 -21.8  -7.2  355  60 31   6.8   3.7 | -20.6  -5.1  325  34 18   5.1   2.8
 20000 -19.7  -3.5  350  59 30   6.8   3.8 | -19.1  -2.4  335  40 21   5.1   2.8
 19500 -18.7  -1.7  350  58 30   6.9   3.8 | -18.4  -1.1  340  44 22   5.1   2.8
 19000 -17.7   0.1  350  57 30   6.9   3.8 | -17.6   0.3  340  47 24   5.1   2.8
 18500 -16.7   1.9  350  57 29   6.8   3.7 | -16.8   1.8  340  49 25   5.2   2.8
 18000 -15.7   3.7  350  57 29   6.8   3.7 | -16.1   3.0  345  51 26   5.2   2.8
 17500 -14.7   5.5  350  57 30   6.7   3.7 | -15.3   4.5  345  52 27   6.0   3.3
 17000 -13.7   7.3  345  58 30   6.7   3.7 | -14.4   6.1  345  53 27   6.2   3.4
 16500 -12.7   9.1  345  58 30   6.7   3.7 | -13.5   7.7  345  53 27   6.3   3.5
 16000 -11.7  10.9  345  58 30   6.8   3.7 | -12.5   9.5  345  54 28   6.6   3.6
 15500 -10.7  12.7  345  59 30   6.8   3.7 | -11.6  11.1  345  54 28   6.6   3.6
 15000  -9.8  14.4  345  59 30   6.3   3.5 | -10.6  12.9  345  54 28   6.1   3.3
 14500  -8.8  16.2  345  59 30   6.5   3.6 |  -9.7  14.5  345  54 28   6.3   3.4
 14000  -7.9  17.8  345  59 31   5.4   3.0 |  -8.9  16.0  345  54 28   4.5   2.5
 13500  -7.1  19.2  345  59 31   5.4   3.0 |  -8.2  17.2  345  54 28   4.7   2.6
 13000  -6.4  20.5  345  59 31   3.9   2.1 |  -7.6  18.3  345  54 28   3.2   1.7
 12500  -5.9  21.4  345  59 30   3.6   2.0 |  -7.2  19.0  345  54 28   3.0   1.6
 12000  -5.4  22.3  345  59 30   3.2   1.7 |  -6.8  19.8  345  54 28   3.3   1.8
 11750  -5.2  22.6  345  58 30   3.5   1.9 |  -6.5  20.3  350  54 28   3.3   1.8
 11500  -4.9  23.2  345  57 30   3.4   1.9 |  -6.3  20.7  350  54 28   3.1   1.7
 11250  -4.7  23.5  345  57 29   3.7   2.0 |  -6.0  21.2  350  54 28   3.8   2.1
 11000  -4.4  24.1  345  56 29   4.9   2.7 |  -5.7  21.7  350  53 27   5.1   2.8
 10750  -4.0  24.8  345  54 28   5.4   3.0 |  -5.3  22.5  350  52 27   5.8   3.2
 10500  -3.6  25.5  345  53 27   5.2   2.8 |  -4.9  23.2  350  51 26   5.8   3.2
 10250  -3.2  26.2  345  51 26   5.4   3.0 |  -4.4  24.1  350  50 26   6.5   3.5
 10000  -2.8  27.0  345  50 26   5.8   3.2 |  -3.3  26.1  350  46 24   7.1   3.9
  9750  -1.9  28.6  345  48 25   6.5   3.5 |  -2.8  27.0  350  44 23   6.3   3.5
  9500  -1.4  29.5  345  47 24   6.5   3.6 |  -2.3  27.9  350  42 22   6.8   3.7
  9250  -0.9  30.4  345  46 24   6.5   3.6 |  -1.8  28.8  350  41 21   7.4   4.1
  9000  -0.4  31.3  345  45 23   6.3   3.5 |  -1.3  29.7  345  39 20   7.3   4.0
  8750  -0.0  32.0  340  44 23   3.4   1.9 |  -0.7  30.7  345  38 19   6.1   3.3
  8500   0.0  32.0  340  42 21  -1.5  -0.8 |  -0.4  31.3  345  35 18   4.5   2.5
  8250  -0.2  31.6  340  38 19  -3.6  -2.0 |  -0.1  31.8  340  32 16   3.8   2.1
  8000  -0.4  31.3  335  34 18  -1.8  -1.0 |   0.2  32.4  340  28 14   5.6   3.1
  7750  -0.7  30.7  335  30 16  -9.6  -5.3 |   0.6  33.1  340  24 12   5.3   2.9
  7500  -2.1  28.2  330  22 12 -25.7 -14.1 |   0.7  33.3  340  18  9  -0.5  -0.3
  7250  -3.4  25.9  325  12  6   5.7   3.1 |   0.8  33.4  335  11  6  11.6   6.4
  7000     M     M    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     M     M

           02/08/2016 at 1400 MST          |       02/08/2016 at 1700 MST
                                           |
K index... +2.9  LI... +277.9              | K index... +3.2  LI... +279.8
CAPE... 0.0  CIN... -1.3                   | CAPE... 0.0  CIN... -0.1
                                           |
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 -57.2 -71.0  335  46 24   0.4   0.2 | -57.7 -71.9  335  47 24   1.0   0.5
 45000 -56.5 -69.7  335  52 27  -1.6  -0.9 | -56.2 -69.2  330  49 25  -2.0  -1.1
 40000 -63.3 -81.9  350  70 36  -4.4  -2.4 | -65.6 -86.1  355  70 36  -6.1  -3.3
 38000 -62.2 -80.0  350  72 37   5.7   3.1 | -63.8 -82.8  355  71 37   8.3   4.5
 36000 -58.8 -73.8  350  72 37   5.7   3.1 | -58.8 -73.8  355  67 34   8.3   4.5
 34000 -54.7 -66.5  355  70 36   9.3   5.1 | -53.6 -64.5  355  64 33   9.4   5.2
 32000 -49.0 -56.2  360  65 34   9.4   5.1 | -48.0 -54.4  355  65 34   9.4   5.2
 30000 -43.6 -46.5  360  64 33   8.6   4.7 | -42.6 -44.7  355  65 34   7.9   4.3
 29000 -41.0 -41.8  005  67 35   8.6   4.7 | -40.3 -40.5  360  65 33   7.9   4.3
 28000 -38.4 -37.1  005  70 36   8.6   4.7 | -37.9 -36.2  005  65 33   7.9   4.3
 27000 -35.2 -31.4  360  70 36   9.0   5.0 | -35.4 -31.7  005  65 33   9.1   5.0
 26000 -32.5 -26.5  360  64 33   9.0   5.0 | -32.0 -25.6  005  62 32   9.1   5.0
 25000 -29.7 -21.5  350  58 30   9.0   5.0 | -29.3 -20.7  360  61 31   9.1   5.0
 24000 -27.1 -16.8  345  52 27   8.5   4.7 | -26.6 -15.9  360  57 29   8.2   4.5
 23000 -24.5 -12.1  340  42 22   8.6   4.7 | -24.1 -11.4  350  50 26   8.2   4.5
 22000 -21.9  -7.4  325  33 17   8.5   4.6 | -21.7  -7.1  340  43 22   8.2   4.5
 21000 -19.9  -3.8  320  31 16   4.5   2.5 | -19.6  -3.3  335  41 21   5.5   3.0
 20000 -18.6  -1.5  330  37 19   4.6   2.5 | -18.0  -0.4  335  42 22   5.5   3.0
 19500 -17.9  -0.2  335  40 20   4.6   2.5 | -17.2   1.0  335  43 22   5.5   3.0
 19000 -17.2   1.0  340  43 22   4.7   2.6 | -16.4   2.5  340  43 22   5.4   3.0
 18500 -16.5   2.3  340  45 23   5.3   2.9 | -15.7   3.7  340  46 24   3.9   2.1
 18000 -15.7   3.7  340  47 24   5.2   2.9 | -15.1   4.8  345  49 25   4.1   2.2
 17500 -14.9   5.2  345  49 25   5.8   3.2 | -14.6   5.7  345  52 27   3.3   1.8
 17000 -14.0   6.8  345  50 26   6.0   3.3 | -14.1   6.6  350  53 27   3.2   1.7
 16500 -13.1   8.4  345  50 26   6.2   3.4 | -13.7   7.3  350  53 28   4.0   2.2
 16000 -12.2  10.0  345  51 26   6.5   3.6 | -12.9   8.8  355  53 27   5.9   3.2
 15500 -11.2  11.8  345  51 26   6.5   3.6 | -12.0  10.4  355  53 27   5.8   3.2
 15000 -10.3  13.5  345  50 26   6.9   3.8 | -11.1  12.0  355  53 27   6.6   3.6
 14500  -9.3  15.3  345  50 26   7.0   3.8 | -10.1  13.8  355  52 27   6.6   3.6
 14000  -8.3  17.1  345  50 26   5.7   3.1 |  -9.2  15.4  355  52 27   5.1   2.8
 13500  -7.5  18.5  345  50 26   5.9   3.2 |  -8.5  16.7  355  51 26   5.3   2.9
 13000  -6.7  19.9  345  49 25   4.0   2.2 |  -7.8  18.0  355  50 26   4.2   2.3
 12500  -6.2  20.8  345  49 25   3.8   2.1 |  -7.2  19.0  350  49 25   4.1   2.3
 12000  -5.7  21.7  345  48 24   3.4   1.9 |  -6.7  19.9  350  47 24   3.8   2.1
 11750  -5.4  22.3  345  47 24   3.5   1.9 |  -6.4  20.5  350  47 24   4.3   2.4
 11500  -5.2  22.6  345  46 24   3.4   1.9 |  -6.0  21.2  350  46 24   4.1   2.2
 11250  -4.9  23.2  345  46 24   3.8   2.1 |  -5.7  21.7  350  45 23   5.0   2.7
 11000  -4.6  23.7  345  45 23   4.7   2.6 |  -5.3  22.5  350  44 23   6.6   3.6
 10750  -4.2  24.4  345  44 22   5.8   3.2 |  -4.8  23.4  350  43 22   7.3   4.0
 10500  -3.7  25.3  345  42 22   6.2   3.4 |  -4.2  24.4  350  42 22   7.2   4.0
 10250  -3.3  26.1  345  41 21   6.9   3.8 |  -3.7  25.3  350  41 21   8.0   4.4
 10000  -2.1  28.2  345  37 19   7.7   4.2 |  -2.4  27.7  350  37 19   8.7   4.8
  9750  -1.6  29.1  340  35 18   6.7   3.6 |  -1.8  28.8  350  35 18   7.6   4.1
  9500  -1.1  30.0  340  33 17   6.6   3.6 |  -1.2  29.8  350  33 17   8.2   4.5
  9250  -0.6  30.9  340  32 16   6.6   3.6 |  -0.5  31.1  345  32 16   9.0   4.9
  9000  -0.1  31.8  335  30 15   6.7   3.7 |   0.1  32.2  345  31 16   8.7   4.7
  8750   0.4  32.7  335  28 14   6.4   3.5 |   0.7  33.3  345  29 15   6.9   3.8
  8500   0.8  33.4  335  25 13   5.3   2.9 |   1.1  34.0  345  28 14   5.5   3.0
  8250   1.1  34.0  335  22 11   4.5   2.5 |   1.5  34.7  340  25 13   5.0   2.8
  8000   1.5  34.7  330  20 10   5.7   3.1 |   1.9  35.4  340  23 12   6.7   3.7
  7750   1.8  35.2  330  17  9   2.5   1.4 |   2.2  36.0  340  21 11  -2.1  -1.1
  7500   1.6  34.9  325  11  6  -5.7  -3.2 |   1.2  34.2  335  14  7 -21.4 -11.8
  7250   1.3  34.3  320   6  3   8.3   4.5 |   0.2  32.4  325   7  4  14.1   7.7
  7000     M     M    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     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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