Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 191041
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0441 MDT Monday, September 19, 2016

This forecast is for Monday, September 19, 2016:

If the trigger temperature of 73.0 F/22.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1028 ft/min (5.2 m/s)
   Maximum height of thermals.................. 17841 ft MSL (11083 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14345 ft MSL (7588 ft AGL)
Thermal soaring outlook for Tuesday 09/20...... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:44:28 / 19:01:29 MDT
Total possible sunshine........... 12 hr 17 min 1 sec (737 min 1 sec)
Altitude of sun at 12:52:29 MDT... 52.15 degrees

Upper air data from numerical model forecast valid on 09/19/2016 at 0600 MDT

Freezing level.................. 15628 ft MSL (8870 ft AGL)
Convective condensation level... 22159 ft MSL (15401 ft AGL)
Lifted condensation level....... 20104 ft MSL (13346 ft AGL)
Lifted index.................... +2.6
K index......................... +11.2

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  -68.5 -91.3   280   45   23   1.9   1.1      M     M       M      M    M
 45000  -63.8 -82.8   275   42   21   6.0   3.3      M     M       M      M    M
 40000  -54.6 -66.3   265   36   18   7.1   3.9      M     M       M      M    M
 38000  -50.3 -58.5   265   33   17   7.1   3.9      M     M       M      M    M
 36000  -46.0 -50.8   270   31   16   7.1   3.9      M     M       M      M    M
 34000  -41.3 -42.3   270   28   14   8.0   4.4      M     M       M      M    M
 32000  -35.9 -32.6   275   24   12   8.3   4.5      M     M       M      M    M
 30000  -30.7 -23.3   280   23   12   8.6   4.7   38.9 102.0     8.6      M    M
 29000  -28.1 -18.6   285   23   12   8.6   4.7   38.5 101.4     8.5      M    M
 28000  -25.6 -14.1   285   23   12   7.4   4.0   38.1 100.6     8.2      M    M
 27000  -23.4 -10.1   285   24   12   7.4   4.0   37.1  98.8     7.5      M    M
 26000  -21.2  -6.2   285   25   13   7.4   4.0   36.2  97.2     6.9      M    M
 25000  -19.0  -2.2   280   26   13   7.3   4.0   35.5  95.9     6.3      M    M
 24000  -16.8   1.8   280   26   13   7.3   4.0   34.5  94.1     5.5      M    M
 23000  -14.6   5.7   280   26   13   7.3   4.0   33.6  92.5     4.8      M    M
 22000  -12.5   9.5   275   26   13   6.9   3.8   32.8  91.1     4.2      M    M
 21000  -10.6  12.9   275   24   12   6.4   3.5   31.6  88.8     3.1      M    M
 20000   -8.7  16.3   275   22   11   6.4   3.5   30.4  86.7     2.1      M    M
 19500   -7.8  18.0   275   21   11   6.4   3.5   29.9  85.8     1.7      M    M
 19000   -6.8  19.8   275   20   10   7.1   3.9   29.4  84.9     1.2      M    M
 18500   -5.8  21.6   270   19   10   7.0   3.8   28.9  84.0     0.8      M    M
 18000   -4.8  23.4   270   18    9   6.5   3.6   28.5  83.2     0.3      M    M
 17500   -3.9  25.0   265   18    9   6.0   3.3   27.8  82.1    -0.3   1008  5.1
 17000   -3.0  26.6   265   18    9   6.0   3.3   27.2  80.9    -0.9    968  4.9
 16500   -2.1  28.2   260   17    9   7.1   3.9   26.7  80.0    -1.4    924  4.7
 16000   -0.6  30.9   255   15    8   7.2   3.9   26.0  78.8    -2.1    857  4.4
 15500    0.6  33.1   250   14    7   8.3   4.5   25.7  78.2    -2.4    807  4.1
 15000    1.8  35.2   255   13    7   8.2   4.5   25.4  77.7    -2.7    756  3.8
 14500    3.0  37.4   255   12    6   8.1   4.4   25.2  77.3    -3.0    705  3.6
 14000    4.2  39.6   260   10    5   8.1   4.4   24.9  76.8    -3.2    654  3.3
 13500    5.4  41.7   270    9    5   8.1   4.5   24.6  76.3    -3.5    603  3.1
 13000    6.6  43.9   275    8    4   8.1   4.4   24.4  75.8    -3.8    552  2.8
 12500    7.9  46.2   290    7    4   8.6   4.7   24.1  75.4    -4.0    500  2.5
 12000    9.2  48.6   300    7    4   8.3   4.5   23.9  75.1    -4.2    447  2.3
 11750    9.8  49.6   305    7    4   8.2   4.5   23.8  74.9    -4.4    421  2.1
 11500   10.4  50.7   310    8    4   8.6   4.7   23.7  74.7    -4.5    395  2.0
 11250   11.0  51.8   320    8    4   8.5   4.7   23.6  74.5    -4.6    368  1.9
 11000   11.7  53.1   320    8    4   8.0   4.4   23.5  74.3    -4.7    342  1.7
 10750   12.3  54.1   325    8    4   8.0   4.4   23.4  74.1    -4.8    317  1.6
 10500   12.9  55.2   330    8    4   8.3   4.5   23.2  73.8    -5.0    292  1.5
 10250   13.5  56.3   335    8    4   8.7   4.8   23.1  73.7    -5.1    265  1.3
 10000   14.2  57.6   335    9    4   8.3   4.5   23.1  73.5    -5.2    238  1.2
  9750   14.8  58.6   340    8    4   8.0   4.4   22.9  73.3    -5.3    212  1.1
  9500   15.4  59.7   340    8    4   8.0   4.4   22.8  73.0    -5.5    187  1.0
  9250   16.0  60.8   345    9    4   7.9   4.3   22.7  72.8    -5.6    162  0.8
  9000   16.6  61.9   345    9    5   8.0   4.4   22.5  72.5    -5.7    136  0.7
  8750   17.2  63.0   345    9    5   8.1   4.4   22.4  72.3    -5.9    111  0.6
  8500   17.7  63.9   345   10    5   5.1   2.8   22.2  71.9    -6.1     87  0.4
  8250   17.9  64.2   340   11    6   0.5   0.3   21.6  70.9    -6.7     74  0.4
  8000   18.1  64.6   335   12    6   8.3   4.6   21.1  70.0    -7.2     61  0.3
  7750   18.3  64.9   330   13    7 -18.4 -10.1   20.6  69.0    -7.8     48  0.2
  7500   15.5  59.9   325   12    6 -33.4 -18.3   17.3  63.2   -11.1    122  0.6
  7250   14.1  57.4   320   11    6 -13.5  -7.4   15.5  59.8   -12.9    159  0.8
  7000   12.6  54.7   310   10    5 -30.8 -16.9   13.6  56.5   -14.8    196  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/19/2016 at 0900 MDT          |       09/19/2016 at 1200 MDT
                                           |
K index... +9.3  LI... +277.6              | K index... +6.8  LI... +277.2
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -68.0 -90.4  280  48 25   2.5   1.4 | -67.9 -90.2  280  49 25   2.6   1.4
 45000 -63.0 -81.4  275  49 25   5.5   3.0 | -62.7 -80.9  275  53 27   5.7   3.1
 40000 -54.6 -66.3  255  34 17   7.0   3.9 | -53.7 -64.7  260  36 19   6.4   3.5
 38000 -49.8 -57.6  260  30 16   7.1   3.9 | -49.9 -57.8  255  31 16   6.4   3.5
 36000 -45.6 -50.1  265  28 14   7.2   4.0 | -46.0 -50.8  245  27 14   6.7   3.7
 34000 -40.9 -41.6  270  24 12   7.8   4.3 | -41.2 -42.2  240  24 13   8.2   4.5
 32000 -36.2 -33.2  270  20 10   7.8   4.3 | -36.3 -33.3  240  22 12   8.2   4.5
 30000 -31.3 -24.3  275  20 10   8.2   4.5 | -31.3 -24.3  240  20 10   8.3   4.5
 29000 -28.9 -20.0  280  20 10   8.2   4.5 | -28.9 -20.0  240  19 10   8.3   4.5
 28000 -26.5 -15.7  280  20 10   7.7   4.2 | -26.4 -15.5  245  18  9   7.8   4.3
 27000 -24.2 -11.6  280  22 11   7.6   4.2 | -24.1 -11.4  250  18 10   7.7   4.2
 26000 -21.9  -7.4  280  23 12   7.6   4.2 | -21.8  -7.2  255  19 10   7.7   4.2
 25000 -19.7  -3.5  280  24 13   7.6   4.1 | -19.0  -2.2  265  20 10   7.4   4.1
 24000 -16.9   1.6  280  25 13   7.4   4.0 | -16.8   1.8  270  20 10   7.3   4.0
 23000 -14.7   5.5  275  24 13   7.4   4.1 | -14.6   5.7  270  21 11   7.3   4.0
 22000 -12.5   9.5  275  24 13   7.0   3.8 | -12.4   9.7  275  21 11   7.2   3.9
 21000 -10.5  13.1  275  23 12   6.9   3.8 | -10.3  13.5  275  21 11   7.2   3.9
 20000  -8.5  16.7  270  22 11   6.9   3.8 |  -8.2  17.2  275  21 11   7.2   3.9
 19500  -7.4  18.7  270  22 11   6.8   3.7 |  -7.1  19.2  270  21 11   7.1   3.9
 19000  -6.5  20.3  270  21 11   6.5   3.6 |  -6.1  21.0  270  21 11   7.0   3.9
 18500  -5.5  22.1  265  20 11   6.5   3.6 |  -5.1  22.8  270  21 11   7.1   3.9
 18000  -4.6  23.7  265  20 10   6.6   3.6 |  -4.1  24.6  270  21 11   6.9   3.8
 17500  -3.6  25.5  260  19 10   6.7   3.7 |  -3.0  26.6  270  20 10   6.9   3.8
 17000  -2.7  27.1  260  18  9   6.7   3.7 |  -2.0  28.4  265  19 10   6.8   3.7
 16500  -1.7  28.9  255  18  9   6.7   3.7 |  -1.0  30.2  265  19 10   6.7   3.7
 16000  -0.8  30.6  255  17  9   6.5   3.6 |  -0.1  31.8  265  18  9   6.7   3.7
 15500   0.3  32.5  255  16  8   8.1   4.4 |   0.9  33.6  265  17  9   6.6   3.6
 15000   1.5  34.7  255  15  8   8.0   4.4 |   1.8  35.2  265  16  8   6.6   3.6
 14500   2.6  36.7  255  13  7   7.4   4.1 |   2.8  37.0  265  14  7   7.0   3.8
 14000   3.7  38.7  260  12  6   7.3   4.0 |   3.9  39.0  265  12  6   7.0   3.9
 13500   4.8  40.6  265  10  5   7.4   4.0 |   4.9  40.8  270  11  6   6.7   3.7
 13000   5.9  42.6  270   8  4   7.4   4.1 |   5.8  42.4  280   8  4   6.4   3.5
 12500   7.0  44.6  285   7  3   6.8   3.7 |   6.8  44.2  295   6  3   6.3   3.5
 12000   8.0  46.4  305   5  3   7.9   4.3 |   7.9  46.2  325   5  2   9.0   4.9
 11750   8.6  47.5  315   5  2   7.5   4.1 |   8.5  47.3  340   4  2   8.6   4.7
 11500   9.2  48.6  325   4  2   8.0   4.4 |   9.2  48.6  355   5  2   8.9   4.9
 11250   9.8  49.6  340   4  2   8.8   4.8 |   9.8  49.6  360   5  2   9.3   5.1
 11000  10.5  50.9  345   5  2   8.6   4.7 |  10.5  50.9  005   5  2   9.7   5.3
 10750  11.1  52.0  350   5  2   8.0   4.4 |  11.2  52.2  005   5  2   9.8   5.4
 10500  11.7  53.1  355   5  3   8.4   4.6 |  12.0  53.6  010   5  2  10.0   5.5
 10250  12.3  54.1  355   6  3   9.0   4.9 |  12.7  54.9  010   5  2  10.6   5.8
 10000  13.0  55.4  355   6  3   9.1   5.0 |  14.3  57.7  010   5  2   8.9   4.9
  9750  14.2  57.6  360   7  3   7.8   4.3 |  14.9  58.8  010   5  2   8.9   4.9
  9500  14.8  58.6  360   7  4   8.8   4.8 |  15.7  60.3  010   5  2  10.4   5.7
  9250  15.5  59.9  360   7  4   9.0   4.9 |  16.4  61.5  010   5  2  11.0   6.0
  9000  16.2  61.2  360   7  4   8.8   4.8 |  17.2  63.0  010   5  2   9.7   5.3
  8750  16.8  62.2  360   7  4   7.6   4.2 |  17.9  64.2  010   5  2   9.5   5.2
  8500  17.3  63.1  355   8  4   6.4   3.5 |  18.7  65.7  015   5  2  10.7   5.9
  8250  17.8  64.0  350   8  4   7.2   4.0 |  19.5  67.1  015   5  2  11.3   6.2
  8000  18.3  64.9  345   9  4   4.1   2.3 |  20.3  68.5  015   5  2   9.3   5.1
  7750  18.3  64.9  340   9  5   0.9   0.5 |  21.1  70.0  015   5  2  14.0   7.7
  7500  18.4  65.1  330   7  4   5.0   2.8 |  22.6  72.7  015   5  2  27.3  15.0
  7250  18.5  65.3  310   5  3  -4.5  -2.5 |  24.1  75.4  015   5  2   2.2   1.2
  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

           09/19/2016 at 1500 MDT          |       09/19/2016 at 1800 MDT
                                           |
K index... +16.2  LI... +275.7             | K index... +21.0  LI... +274.4
CAPE... 0.0  CIN... -0.2                   | CAPE... 0.0  CIN... M
                                           |
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 -68.2 -90.8  275  55 28   2.7   1.5 | -67.7 -89.9  275  56 29   2.3   1.3
 45000 -62.7 -80.9  280  64 33   6.1   3.4 | -62.6 -80.7  275  69 36   6.1   3.3
 40000 -53.0 -63.4  275  53 27   6.3   3.4 | -52.9 -63.2  275  69 36   6.8   3.7
 38000 -49.3 -56.7  265  43 22   6.3   3.4 | -48.8 -55.8  275  61 31   6.8   3.7
 36000 -45.5 -49.9  255  34 17   6.3   3.5 | -44.7 -48.5  275  53 27   6.8   3.7
 34000 -41.1 -42.0  250  31 16   7.4   4.1 | -40.4 -40.7  270  44 23   7.3   4.0
 32000 -36.7 -34.1  245  28 14   7.4   4.0 | -36.1 -33.0  265  35 18   7.3   4.0
 30000 -32.1 -25.8  245  27 14   7.7   4.2 | -31.9 -25.4  255  29 15   6.9   3.8
 29000 -29.8 -21.6  245  26 14   7.7   4.2 | -29.3 -20.7  250  26 13   6.9   3.8
 28000 -26.8 -16.2  245  25 13   8.6   4.7 | -27.1 -16.8  240  24 13   8.5   4.7
 27000 -24.3 -11.7  250  24 12   8.5   4.7 | -24.6 -12.3  245  23 12   8.3   4.6
 26000 -21.7  -7.1  250  22 12   8.5   4.7 | -22.1  -7.8  245  22 11   8.3   4.6
 25000 -19.2  -2.6  250  21 11   7.8   4.3 | -19.6  -3.3  245  21 11   7.8   4.3
 24000 -17.0   1.4  255  20 10   7.4   4.1 | -17.4   0.7  250  19 10   7.3   4.0
 23000 -14.8   5.4  260  19 10   7.4   4.1 | -15.3   4.5  255  18 10   7.4   4.0
 22000 -12.6   9.3  265  19 10   7.1   3.9 | -13.1   8.4  255  18  9   6.6   3.6
 21000 -10.6  12.9  270  19 10   6.9   3.8 | -11.3  11.7  265  18  9   6.2   3.4
 20000  -8.5  16.7  275  19 10   7.0   3.8 |  -9.5  14.9  270  19 10   6.3   3.5
 19500  -7.5  18.5  275  19 10   6.9   3.8 |  -8.6  16.5  275  20 10   6.6   3.6
 19000  -6.6  20.1  275  20 10   6.3   3.4 |  -7.6  18.3  275  19 10   8.2   4.5
 18500  -5.7  21.7  275  20 10   6.4   3.5 |  -6.4  20.5  270  18  9   8.2   4.5
 18000  -4.8  23.4  275  20 10   6.5   3.5 |  -5.3  22.5  265  16  8   8.6   4.7
 17500  -3.8  25.2  275  19 10   6.5   3.6 |  -4.1  24.6  260  14  7   8.7   4.8
 17000  -2.9  26.8  280  18  9   6.7   3.7 |  -2.8  27.0  255  11  6   8.7   4.8
 16500  -1.9  28.6  280  16  8   7.7   4.2 |  -1.6  29.1  250   9  5   8.2   4.5
 16000  -0.8  30.6  280  14  7   7.7   4.2 |  -0.4  31.3  240   6  3   8.2   4.5
 15500   0.3  32.5  280  11  6   7.5   4.1 |   0.9  33.6  230   4  2   8.1   4.5
 15000   1.4  34.5  285   7  4   7.5   4.1 |   2.1  35.8  195   3  2   8.1   4.5
 14500   2.5  36.5  300   3  2   7.7   4.2 |   3.9  39.0  150   4  2   8.2   4.5
 14000   4.3  39.7  025   1  1   7.8   4.3 |   5.2  41.4  140   5  2   8.2   4.5
 13500   5.5  41.9  060   3  1   9.0   5.0 |   6.4  43.5  135   6  3   8.5   4.6
 13000   6.8  44.2  070   3  2   9.3   5.1 |   7.7  45.9  130   6  3   8.5   4.6
 12500   8.1  46.6  075   3  2   8.3   4.6 |   9.0  48.2  130   7  4   8.7   4.7
 12000   9.5  49.1  080   3  2   9.7   5.3 |  10.3  50.5  130   7  4   8.7   4.8
 11750  10.2  50.4  080   3  2   9.8   5.4 |  10.9  51.6  130   7  4   8.6   4.7
 11500  11.0  51.8  080   3  2   9.9   5.5 |  11.6  52.9  130   7  4   9.6   5.3
 11250  11.7  53.1  085   3  2   9.9   5.4 |  12.3  54.1  135   7  4   9.2   5.1
 11000  12.4  54.3  085   3  2   9.7   5.3 |  12.9  55.2  135   7  4   8.1   4.5
 10750  13.2  55.8  085   4  2   9.7   5.3 |  13.6  56.5  135   7  4   8.3   4.6
 10500  13.9  57.0  090   4  2   9.7   5.3 |  14.2  57.6  135   7  4   8.8   4.8
 10250  14.6  58.3  090   4  2   9.6   5.3 |  14.9  58.8  135   7  4   9.5   5.2
 10000  15.3  59.5  090   4  2   9.8   5.4 |  15.5  59.9  140   7  4   7.9   4.3
  9750  16.1  61.0  095   4  2  10.0   5.5 |  16.0  60.8  140   7  4   6.6   3.6
  9500  16.8  62.2  095   4  2  10.0   5.5 |  16.6  61.9  145   7  4   7.9   4.3
  9250  17.6  63.7  095   4  2  10.1   5.5 |  17.2  63.0  150   7  3   8.5   4.7
  9000  18.3  64.9  100   4  2   9.9   5.4 |  17.8  64.0  155   6  3   8.5   4.7
  8750  19.0  66.2  100   4  2   9.8   5.4 |  18.4  65.1  160   7  3   9.2   5.1
  8500  19.8  67.6  100   4  2  10.3   5.7 |  19.2  66.6  165   7  3   9.4   5.2
  8250  20.6  69.1  105   4  2  10.7   5.9 |  19.8  67.6  170   7  3   9.2   5.0
  8000  21.4  70.5  105   4  2  10.5   5.8 |  20.5  68.9  175   7  3   9.6   5.3
  7750  22.2  72.0  105   4  2  11.0   6.0 |  21.2  70.2  175   7  4   8.2   4.5
  7500  23.0  73.4  105   4  2  11.2   6.1 |  21.7  71.1  175   7  4   5.7   3.1
  7250  23.8  74.8  105   4  2  10.8   5.9 |  22.0  71.6  175   6  3   5.1   2.8
  7000  24.5  76.1  105   4  2  11.2   6.1 |  22.4  72.3  175   6  3   5.5   3.0
  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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