Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 131132
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0432 MST Saturday, February 13, 2016

This forecast is for Saturday, February 13, 2016:

If the trigger temperature of 61.1 F/16.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 216 ft/min (1.1 m/s)
   Maximum height of thermals.................. 9574 ft MSL (2816 ft AGL)

Forecast maximum temperature................... 59.0 F/15.5 C
Time of trigger temperature.................... None
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................. 7917 ft MSL (1160 ft AGL)
Thermal soaring outlook for Sunday 02/14....... Fair

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

Remarks...

Sunrise/Sunset.................... 06:53:02 / 17:32:29 MST
Total possible sunshine........... 10 hr 39 min 28 sec (639 min 28 sec)
Altitude of sun at 12:13:04 MST... 37.74 degrees

Upper air data from numerical model forecast valid on 02/13/2016 at 0500 MST

Freezing level.................. 6778 ft MSL (20 ft AGL)
Additional freezing level....... 13043 ft MSL (6285 ft AGL)
Convective condensation level... 18908 ft MSL (12150 ft AGL)
Lifted condensation level....... 16777 ft MSL (10019 ft AGL)
Lifted index.................... +2.6
K index......................... -6.2

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  -61.1 -78.0   285   53   27   1.5   0.8      M     M       M      M    M
 45000  -59.0 -74.2   285   84   43  -1.5  -0.8      M     M       M      M    M
 40000  -63.7 -82.7   280   70   36  -2.9  -1.6      M     M       M      M    M
 38000  -61.4 -78.5   280   65   34   7.1   3.9      M     M       M      M    M
 36000  -57.1 -70.8   280   61   31   7.1   3.9      M     M       M      M    M
 34000  -52.7 -62.9   280   57   29   8.3   4.6      M     M       M      M    M
 32000  -47.7 -53.9   280   54   28   8.3   4.5      M     M       M      M    M
 30000  -42.8 -45.0   280   49   25   7.9   4.3   26.8  80.3     9.1      M    M
 29000  -40.5 -40.9   280   46   24   7.9   4.3   26.0  78.9     8.6      M    M
 28000  -37.5 -35.5   280   42   22   7.9   4.3   25.3  77.5     8.1      M    M
 27000  -35.2 -31.4   280   40   20   7.9   4.3   24.6  76.2     7.6      M    M
 26000  -32.8 -27.0   280   37   19   7.9   4.3   23.8  74.8     7.1      M    M
 25000  -30.5 -22.9   280   34   18   7.9   4.3   23.1  73.7     6.6      M    M
 24000  -28.1 -18.6   280   32   16   8.0   4.4   22.5  72.5     6.2      M    M
 23000  -25.7 -14.3   275   29   15   8.0   4.4   21.8  71.3     5.7      M    M
 22000  -23.3  -9.9   275   27   14   8.0   4.4   21.3  70.3     5.3      M    M
 21000  -20.9  -5.6   275   25   13   8.3   4.6   20.7  69.3     4.8      M    M
 20000  -18.4  -1.1   275   23   12   8.3   4.6   20.2  68.3     4.4      M    M
 19500  -17.2   1.0   270   22   11   8.3   4.6   20.0  67.9     4.3      M    M
 19000  -15.9   3.4   270   21   11   8.4   4.6   19.8  67.6     4.1      M    M
 18500  -14.6   5.7   270   21   11   9.0   4.9   19.6  67.3     4.0      M    M
 18000  -13.3   8.1   270   20   10   9.0   4.9   19.5  67.0     3.9      M    M
 17500  -11.9  10.6   270   20   10   8.8   4.8   19.3  66.8     3.8      M    M
 17000  -10.6  12.9   275   20   10   8.8   4.8   19.2  66.5     3.6      M    M
 16500   -9.3  15.3   275   19   10   8.8   4.8   19.0  66.2     3.5      M    M
 16000   -8.0  17.6   280   20   10   8.8   4.8   18.8  65.9     3.4      M    M
 15500   -6.7  19.9   280   20   10   8.8   4.9   18.7  65.7     3.3      M    M
 15000   -5.4  22.3   285   20   10   8.7   4.8   18.5  65.4     3.1      M    M
 14500   -4.1  24.6   285   21   11   8.7   4.8   18.4  65.0     3.0      M    M
 14000   -2.2  28.0   290   22   11   8.5   4.7   18.1  64.5     2.7      M    M
 13500   -0.9  30.4   290   23   12   8.5   4.7   17.9  64.2     2.6      M    M
 13000    0.4  32.7   290   23   12   8.5   4.7   17.7  63.8     2.4      M    M
 12500    1.6  34.9   290   24   12   8.0   4.4   17.5  63.5     2.2      M    M
 12000    2.8  37.0   295   24   13   8.1   4.4   17.2  62.9     1.9      M    M
 11750    3.4  38.1   295   24   13   8.0   4.4   17.0  62.6     1.8      M    M
 11500    4.0  39.2   295   25   13   8.1   4.4   16.9  62.4     1.6      M    M
 11250    4.6  40.3   295   25   13   7.5   4.1   16.8  62.2     1.5      M    M
 11000    5.1  41.2   290   23   12   7.1   3.9   16.5  61.8     1.3      M    M
 10750    5.6  42.1   290   22   11   7.3   4.0   16.3  61.4     1.1      M    M
 10500    6.1  43.0   290   21   11   7.3   4.0   16.2  61.1     0.9      M    M
 10250    6.6  43.9   290   20   10   6.7   3.7   16.0  60.7     0.7      M    M
 10000    7.1  44.8   290   21   11   6.4   3.5   15.7  60.3     0.4      M    M
  9750    7.6  45.7   290   21   11   6.9   3.8   15.5  59.8     0.1      M    M
  9500    8.0  46.4   290   21   11   6.9   3.8   15.2  59.4    -0.1    206  1.0
  9250    8.5  47.3   285   21   11   7.1   3.9   15.0  59.0    -0.4    184  0.9
  9000    9.0  48.2   285   22   11   6.9   3.8   14.8  58.7    -0.6    162  0.8
  8750    9.5  49.1   285   22   12   7.9   4.3   14.6  58.3    -0.8    139  0.7
  8500   10.0  50.0   280   24   12   4.8   2.6   14.4  58.0    -1.1    117  0.6
  8250   10.1  50.2   280   24   12  -0.9  -0.5   13.8  56.8    -1.7    107  0.5
  8000    9.8  49.6   280   23   12  -7.9  -4.3   12.8  55.0    -2.7    108  0.5
  7750    9.6  49.3   275   22   11  10.8   6.0   11.8  53.2    -3.7    109  0.6
  7500   10.4  50.7   270   20   10 -11.7  -6.4   11.9  53.5    -3.6     76  0.4
  7250    7.2  45.0   275   17    8 -58.6 -32.1    8.3  47.0    -7.2    166  0.8
  7000    3.4  38.1   275   12    6 -31.3 -17.2    4.3  39.8   -11.3    271  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           02/13/2016 at 0800 MST          |       02/13/2016 at 1100 MST
                                           |
K index... -14.9  LI... +274.9             | K index... -36.1  LI... +275.6
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -0.6
                                           |
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  280  57 30   1.2   0.6 | -58.6 -73.5  280  60 31  -0.2  -0.1
 45000 -58.3 -72.9  280  89 46  -1.5  -0.8 | -58.8 -73.8  275  89 46  -2.0  -1.1
 40000 -64.3 -83.7  280  73 38  -3.8  -2.1 | -63.8 -82.8  275  76 39  -3.4  -1.8
 38000 -62.2 -80.0  280  68 35   7.4   4.1 | -62.3 -80.1  275  71 37   7.0   3.9
 36000 -57.7 -71.9  280  63 32   7.4   4.1 | -58.1 -72.6  275  66 34   7.0   3.9
 34000 -53.2 -63.8  280  58 30   7.8   4.3 | -53.1 -63.6  275  61 31   8.0   4.4
 32000 -48.6 -55.5  280  54 28   7.8   4.3 | -48.3 -54.9  270  57 29   8.0   4.4
 30000 -43.8 -46.8  280  51 26   8.3   4.5 | -43.5 -46.3  270  53 27   8.3   4.5
 29000 -41.3 -42.3  280  49 25   8.3   4.5 | -41.0 -41.8  265  50 26   8.3   4.5
 28000 -38.8 -37.8  280  46 24   8.3   4.5 | -38.5 -37.3  260  48 25   8.3   4.5
 27000 -35.7 -32.3  280  44 23   8.4   4.6 | -36.0 -32.8  255  45 23   8.6   4.7
 26000 -33.2 -27.8  280  42 22   8.4   4.6 | -33.4 -28.1  260  41 21   8.6   4.7
 25000 -30.7 -23.3  280  40 20   8.4   4.6 | -30.8 -23.4  265  37 19   8.6   4.7
 24000 -28.2 -18.8  280  37 19   8.5   4.7 | -28.2 -18.8  265  34 18   8.6   4.7
 23000 -25.6 -14.1  280  34 17   8.5   4.7 | -25.6 -14.1  270  34 18   8.6   4.7
 22000 -23.1  -9.6  280  31 16   8.5   4.7 | -23.0  -9.4  270  34 18   8.6   4.7
 21000 -20.5  -4.9  280  27 14   8.3   4.5 | -20.4  -4.7  275  33 17   8.3   4.5
 20000 -18.1  -0.6  275  24 13   8.3   4.5 | -17.9  -0.2  275  30 16   8.3   4.6
 19500 -16.8   1.8  275  23 12   8.3   4.5 | -16.7   1.9  275  29 15   8.3   4.6
 19000 -15.6   3.9  275  22 11   8.3   4.6 | -15.5   4.1  280  28 14   8.3   4.6
 18500 -14.3   6.3  275  21 11   8.6   4.7 | -14.2   6.4  280  26 14   8.0   4.4
 18000 -13.1   8.4  275  20 10   8.6   4.7 | -13.0   8.6  280  25 13   8.0   4.4
 17500 -11.8  10.8  275  20 10   8.6   4.7 | -11.8  10.8  285  24 12   8.1   4.4
 17000 -10.5  13.1  275  19 10   8.6   4.7 | -10.6  12.9  285  25 13   8.1   4.5
 16500  -9.2  15.4  275  19 10   8.5   4.7 |  -9.4  15.1  290  26 13   8.1   4.5
 16000  -7.9  17.8  275  19 10   8.4   4.6 |  -7.6  18.3  295  26 14   7.9   4.4
 15500  -6.7  19.9  280  20 10   8.4   4.6 |  -6.4  20.5  295  26 14   7.9   4.4
 15000  -5.4  22.3  280  20 10   8.3   4.5 |  -5.2  22.6  300  28 14   7.9   4.4
 14500  -4.2  24.4  280  21 11   8.3   4.6 |  -4.0  24.8  300  29 15   7.9   4.4
 14000  -2.4  27.7  285  23 12   8.2   4.5 |  -2.8  27.0  300  31 16   7.9   4.3
 13500  -1.1  30.0  285  24 12   8.2   4.5 |  -1.6  29.1  300  32 16   7.8   4.3
 13000   0.1  32.2  285  25 13   8.5   4.6 |  -0.4  31.3  300  33 17   8.3   4.5
 12500   1.4  34.5  285  26 14   7.3   4.0 |   0.8  33.4  300  35 18   7.4   4.1
 12000   2.4  36.3  290  28 14   8.0   4.4 |   1.8  35.2  300  36 18   7.0   3.8
 11750   3.0  37.4  290  28 15   7.7   4.2 |   2.3  36.1  300  36 19   7.7   4.2
 11500   3.6  38.5  290  29 15   7.8   4.3 |   2.9  37.2  300  36 19   7.5   4.1
 11250   4.1  39.4  290  29 15   7.9   4.3 |   3.5  38.3  300  37 19   7.6   4.2
 11000   4.7  40.5  290  28 14   7.9   4.3 |   4.0  39.2  300  37 19   7.2   3.9
 10750   5.3  41.5  285  27 14   7.7   4.2 |   4.5  40.1  300  37 19   6.8   3.8
 10500   5.8  42.4  285  26 13   8.2   4.5 |   5.0  41.0  295  37 19   7.0   3.8
 10250   6.4  43.5  285  25 13   6.6   3.6 |   5.6  42.1  295  37 19   6.9   3.8
 10000   6.9  44.4  290  27 14   6.5   3.5 |   6.1  43.0  295  37 19   7.1   3.9
  9750   7.4  45.3  290  28 15   8.2   4.5 |   6.6  43.9  295  36 18   7.4   4.0
  9500   8.0  46.4  290  30 15   8.2   4.5 |   7.1  44.8  295  35 18   7.7   4.2
  9250   8.6  47.5  290  31 16   6.8   3.8 |   7.7  45.9  295  34 18   6.8   3.7
  9000   9.1  48.4  285  30 15   5.5   3.0 |   8.1  46.6  295  33 17   5.9   3.2
  8750   9.5  49.1  285  29 15   5.9   3.2 |   8.5  47.3  290  31 16   5.2   2.8
  8500   9.9  49.8  285  29 15   4.0   2.2 |   8.8  47.8  290  30 15   4.0   2.2
  8250   9.9  49.8  285  28 14  -2.0  -1.1 |   9.0  48.2  285  28 14  -0.1  -0.0
  8000   9.5  49.1  280  27 14  -8.7  -4.8 |   8.7  47.7  285  25 13  -4.3  -2.3
  7750   9.0  48.2  280  26 13   3.8   2.1 |   8.4  47.1  285  22 11   1.5   0.8
  7500   9.3  48.7  275  24 12  -8.5  -4.7 |   8.5  47.3  280  18  9  -1.9  -1.1
  7250   7.1  44.8  275  19 10 -42.1 -23.1 |   7.7  45.9  280  14  7 -14.9  -8.2
  7000   3.9  39.0  280  14  7 -35.9 -19.7 |   6.3  43.3  280  11  5 -14.8  -8.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           02/13/2016 at 1400 MST          |       02/13/2016 at 1700 MST
                                           |
K index... -26.2  LI... +275.9             | K index... -0.8  LI... +277.2
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -58.1 -72.6  280  68 35  -0.2  -0.1 | -57.7 -71.9  280  70 36  -1.2  -0.7
 45000 -58.4 -73.1  275  92 47  -1.9  -1.0 | -59.7 -75.5  280  86 44  -2.0  -1.1
 40000 -63.7 -82.7  275  78 40  -3.5  -1.9 | -64.0 -83.2  275  78 40  -2.9  -1.6
 38000 -62.3 -80.1  275  73 38   7.1   3.9 | -62.5 -80.5  275  76 39   7.1   3.9
 36000 -58.0 -72.4  275  70 36   7.1   3.9 | -58.2 -72.8  275  73 38   7.1   3.9
 34000 -53.6 -64.5  275  66 34   8.2   4.5 | -53.8 -64.8  275  70 36   8.1   4.5
 32000 -48.1 -54.6  270  60 31   8.2   4.5 | -48.9 -56.0  275  64 33   8.1   4.5
 30000 -43.2 -45.8  270  54 28   8.0   4.4 | -43.4 -46.1  275  56 29   8.2   4.5
 29000 -40.8 -41.4  265  50 26   8.0   4.4 | -41.0 -41.8  275  52 27   8.2   4.5
 28000 -38.4 -37.1  255  47 24   8.0   4.4 | -38.5 -37.3  275  48 25   8.2   4.5
 27000 -35.9 -32.6  250  44 23   8.6   4.7 | -36.0 -32.8  270  44 23   9.7   5.3
 26000 -33.4 -28.1  250  40 21   8.6   4.7 | -33.1 -27.6  270  41 21   9.6   5.3
 25000 -30.8 -23.4  250  36 18   8.5   4.7 | -30.2 -22.4  265  39 20   9.6   5.3
 24000 -28.2 -18.8  245  32 17   8.9   4.9 | -27.4 -17.3  265  36 19   9.0   4.9
 23000 -25.5 -13.9  255  32 17   9.0   4.9 | -24.8 -12.6  270  36 19   8.8   4.8
 22000 -22.8  -9.0  260  33 17   9.0   4.9 | -22.1  -7.8  280  36 19   8.8   4.8
 21000 -20.2  -4.4  270  33 17   7.8   4.3 | -19.7  -3.5  285  37 19   6.3   3.5
 20000 -17.8  -0.0  275  33 17   7.9   4.4 | -17.7   0.1  290  39 20   6.5   3.6
 19500 -16.6   2.1  275  33 17   7.9   4.4 | -16.8   1.8  290  40 21   6.6   3.6
 19000 -15.4   4.3  280  33 17   8.0   4.4 | -15.8   3.6  295  42 21   6.6   3.6
 18500 -14.3   6.3  280  33 17   7.1   3.9 | -14.8   5.4  295  43 22   5.9   3.2
 18000 -13.2   8.2  285  33 17   7.0   3.9 | -14.0   6.8  295  44 23   5.7   3.1
 17500 -12.2  10.0  285  33 17   6.9   3.8 | -13.1   8.4  300  46 23   5.6   3.1
 17000 -11.2  11.8  290  35 18   6.6   3.6 | -12.3   9.9  300  45 23   5.3   2.9
 16500 -10.2  13.6  290  36 19   6.7   3.7 | -11.5  11.3  300  44 23   5.3   2.9
 16000  -9.2  15.4  290  37 19   6.5   3.5 | -10.7  12.7  305  42 22   5.4   3.0
 15500  -7.7  18.1  295  38 20   6.6   3.6 |  -9.9  14.2  305  40 21   5.4   3.0
 15000  -6.7  19.9  295  39 20   7.1   3.9 |  -9.1  15.6  305  38 20   6.0   3.3
 14500  -5.6  21.9  295  39 20   7.1   3.9 |  -7.7  18.1  310  34 17   6.3   3.5
 14000  -4.6  23.7  300  38 20   6.9   3.8 |  -6.7  19.9  310  32 16   6.6   3.6
 13500  -3.6  25.5  300  37 19   6.9   3.8 |  -5.8  21.6  315  31 16   6.6   3.6
 13000  -2.5  27.5  300  35 18   7.8   4.3 |  -4.7  23.5  315  29 15   8.0   4.4
 12500  -1.3  29.7  300  33 17   7.7   4.2 |  -3.5  25.7  315  27 14   8.2   4.5
 12000  -0.5  31.1  300  32 17   5.8   3.2 |  -2.6  27.3  315  27 14   5.8   3.2
 11750   0.0  32.0  300  31 16   7.3   4.0 |  -2.1  28.2  310  25 13   8.1   4.5
 11500   0.5  32.9  305  31 16   7.0   3.8 |  -1.5  29.3  310  23 12   7.6   4.2
 11250   1.1  34.0  305  30 15   6.9   3.8 |  -1.0  30.2  310  21 11   7.4   4.0
 11000   1.6  34.9  300  29 15   6.8   3.7 |  -0.4  31.3  310  20 11   8.0   4.4
 10750   2.0  35.6  300  28 14   6.9   3.8 |   0.2  32.4  305  19 10   9.0   4.9
 10500   2.5  36.5  300  26 13   7.1   3.9 |   0.8  33.4  305  18  9   8.8   4.8
 10250   3.0  37.4  300  25 13   6.6   3.6 |   1.5  34.7  300  17  9   8.5   4.7
 10000   3.5  38.3  300  23 12   7.1   3.9 |   2.1  35.8  300  16  8   8.9   4.9
  9750   4.0  39.2  300  22 11   8.7   4.8 |   2.8  37.0  300  15  8   9.9   5.4
  9500   4.7  40.5  295  20 10   9.2   5.0 |   3.5  38.3  300  15  7  10.2   5.6
  9250   5.3  41.5  295  19 10   8.4   4.6 |   4.3  39.7  300  14  7   9.6   5.3
  9000   5.8  42.4  295  17  9   7.5   4.1 |   4.9  40.8  295  13  7   8.8   4.8
  8750   6.4  43.5  290  16  8   8.8   4.8 |   5.6  42.1  295  13  7   9.7   5.3
  8500   7.1  44.8  290  15  8  10.1   5.5 |   6.4  43.5  295  12  6  10.8   5.9
  8250   7.7  45.9  285  13  7   8.0   4.4 |   7.1  44.8  295  12  6   9.0   4.9
  8000   8.2  46.8  285  12  6   5.9   3.2 |   7.7  45.9  290  11  6   6.7   3.7
  7750   8.6  47.5  280  11  6   8.6   4.7 |   8.2  46.8  290  10  5   9.2   5.0
  7500   9.3  48.7  275   9  5   6.4   3.5 |   8.9  48.0  285   8  4   6.6   3.6
  7250   9.3  48.7  270   7  4  -3.0  -1.7 |   8.9  48.0  280   7  4  -6.3  -3.5
  7000   8.7  47.7  270   6  3  -7.2  -4.0 |   7.9  46.2  280   6  3 -16.2  -8.9
  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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