Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 021238
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0638 MDT Sunday, August 2, 2015

This forecast is for Sunday, August 2, 2015:

If the trigger temperature of 76.5 F/24.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 995 ft/min (5.1 m/s)
   Maximum height of thermals.................. 18795 ft MSL (12037 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 0900 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10467 ft MSL (3710 ft AGL)
Thermal soaring outlook for Monday 08/03....... Good

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

Remarks...

Sunrise/Sunset.................... 06:00:35 / 20:10:15 MDT
Total possible sunshine........... 14 hr 9 min 39 sec (849 min 39 sec)
Altitude of sun at 13:05:11 MDT... 68.72 degrees

Upper air data from numerical model forecast valid on 08/02/2015 at 0600 MDT

Freezing level.................. 15980 ft MSL (9222 ft AGL)
Convective condensation level... 15849 ft MSL (9091 ft AGL)
Lifted condensation level....... 16086 ft MSL (9329 ft AGL)
Lifted index.................... -2.0
K index......................... +22.6

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  -66.7 -88.1   285   35   18   1.7   0.9      M     M       M      M    M
 45000  -61.9 -79.4   280   54   28   6.2   3.4      M     M       M      M    M
 40000  -52.2 -62.0   270   63   32   7.9   4.4      M     M       M      M    M
 38000  -47.4 -53.3   275   55   28   7.9   4.4      M     M       M      M    M
 36000  -42.6 -44.7   280   47   24   7.9   4.4      M     M       M      M    M
 34000  -37.6 -35.7   285   36   18   7.4   4.0      M     M       M      M    M
 32000  -33.2 -27.8   290   25   13   8.2   4.5      M     M       M      M    M
 30000  -28.3 -18.9   285   17    9   8.3   4.6   41.7 107.1    10.8      M    M
 29000  -25.8 -14.4   280   13    7   8.4   4.6   41.3 106.3    10.5      M    M
 28000  -23.5 -10.3   270   10    5   6.7   3.7   40.7 105.3    10.1      M    M
 27000  -21.5  -6.7   265   10    5   6.7   3.7   39.4 103.0     9.2      M    M
 26000  -19.5  -3.1   255   10    5   6.7   3.7   38.3 100.9     8.3      M    M
 25000  -17.6   0.3   245   10    5   6.6   3.6   37.3  99.1     7.5      M    M
 24000  -15.8   3.6   260    7    4   6.1   3.4   35.9  96.6     6.4      M    M
 23000  -14.0   6.8   290    5    2   6.1   3.4   34.6  94.3     5.3      M    M
 22000  -12.2  10.0   340    5    3   5.9   3.2   33.4  92.1     4.4      M    M
 21000  -10.6  12.9   025    5    3   5.4   3.0   31.8  89.3     3.0      M    M
 20000   -9.0  15.8   055    7    4   5.4   3.0   30.3  86.6     1.7      M    M
 19500   -8.2  17.2   060    8    4   5.5   3.0   29.6  85.3     1.1      M    M
 19000   -7.4  18.7   065    9    5   5.3   2.9   28.9  84.0     0.4      M    M
 18500   -6.6  20.1   070    9    5   5.4   2.9   28.1  82.6    -0.3   1180  6.0
 18000   -5.8  21.6   075    9    5   6.8   3.7   27.4  81.3    -1.0   1141  5.8
 17500   -4.6  23.7   080    9    5   8.9   4.9   27.2  81.0    -1.2   1088  5.5
 17000   -3.2  26.2   085    9    5   8.8   4.8   27.1  80.7    -1.3   1034  5.3
 16500   -1.9  28.6   090    9    5  10.0   5.5   27.0  80.6    -1.4    978  5.0
 16000    0.3  32.5   100    7    4   9.9   5.4   27.0  80.7    -1.4    891  4.5
 15500    1.6  34.9   120    6    3   8.5   4.7   26.9  80.5    -1.6    836  4.2
 15000    2.9  37.2   145    6    3   8.6   4.7   26.8  80.2    -1.8    784  4.0
 14500    4.2  39.6   165    7    4   8.6   4.7   26.6  79.8    -2.0    731  3.7
 14000    5.5  41.9   175    8    4   8.6   4.7   26.4  79.5    -2.1    676  3.4
 13500    6.8  44.2   185    8    4   8.9   4.9   26.2  79.2    -2.3    621  3.2
 13000    8.2  46.8   200    8    4   9.1   5.0   26.1  79.0    -2.4    565  2.9
 12500    9.5  49.1   210    8    4   8.5   4.6   26.0  78.7    -2.5    510  2.6
 12000   10.9  51.6   215    9    5   9.5   5.2   25.8  78.5    -2.6    455  2.3
 11750   11.6  52.9   220    9    5   9.5   5.2   25.8  78.5    -2.7    427  2.2
 11500   12.3  54.1   220   10    5   8.9   4.9   25.8  78.4    -2.7    398  2.0
 11250   12.9  55.2   225   10    5   9.0   5.0   25.7  78.3    -2.8    371  1.9
 11000   13.6  56.5   225   10    5   9.8   5.4   25.7  78.2    -2.9    344  1.7
 10750   14.3  57.7   225   10    5   9.8   5.4   25.7  78.2    -2.9    317  1.6
 10500   14.9  58.8   225   10    5   9.3   5.1   25.7  78.2    -3.0    289  1.5
 10250   15.5  59.9   225   10    5   8.0   4.4   25.6  78.1    -3.2    264  1.3
 10000   16.1  61.0   230   10    5   9.1   5.0   25.5  77.9    -3.3    240  1.2
  9750   16.8  62.2   230    9    5  10.4   5.7   25.5  77.9    -3.3    211  1.1
  9500   17.5  63.5   230    9    4   9.2   5.0   25.5  77.9    -3.4    182  0.9
  9250   18.1  64.6   230    8    4   7.7   4.2   25.4  77.7    -3.5    156  0.8
  9000   18.7  65.7   230    8    4   7.6   4.1   25.2  77.4    -3.7    133  0.7
  8750   19.2  66.6   230    7    4   9.4   5.1   25.1  77.2    -3.9    108  0.5
  8500   19.9  67.8   230    7    3   6.6   3.6   25.1  77.1    -3.9     81  0.4
  8250   20.1  68.2   240    7    3   2.6   1.4   24.6  76.3    -4.5     67  0.3
  8000   20.3  68.5   245    7    3   2.9   1.6   24.1  75.4    -5.0     55  0.3
  7750   20.4  68.7   250    7    4   2.4   1.3   23.6  74.4    -5.6     43  0.2
  7500   20.2  68.4   255    8    4  -7.6  -4.2   22.8  73.0    -6.6     43  0.2
  7250   19.1  66.4   260    7    4 -15.8  -8.7   21.4  70.6    -8.0     68  0.3
  7000   18.0  64.4   270    6    3  -9.5  -5.2   20.1  68.2    -9.5     94  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/02/2015 at 0900 MDT          |       08/02/2015 at 1200 MDT
                                           |
K index... +21.7  LI... +269.4             | K index... +23.4  LI... +270.5
CAPE... +292.2  CIN... -31.1               | CAPE... +190.4  CIN... -8.6
                                           |
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 -66.6 -87.9  285  33 17   2.1   1.1 | -66.6 -87.9  285  33 17   1.8   1.0
 45000 -61.6 -78.9  280  51 26   5.9   3.2 | -61.7 -79.1  275  49 25   6.4   3.5
 40000 -52.4 -62.3  270  61 31   7.6   4.1 | -51.5 -60.7  265  60 31   7.1   3.9
 38000 -47.8 -54.0  275  53 27   7.6   4.1 | -47.2 -53.0  265  51 26   7.1   3.9
 36000 -43.3 -45.9  275  46 24   7.6   4.2 | -42.9 -45.2  265  42 22   7.8   4.3
 34000 -37.8 -36.0  280  36 18   8.2   4.5 | -37.7 -35.9  270  34 18   8.7   4.8
 32000 -32.8 -27.0  285  27 14   8.8   4.8 | -32.5 -26.5  285  27 14   9.3   5.1
 30000 -28.1 -18.6  280  19 10   7.9   4.3 | -27.8 -18.0  280  20 11   7.9   4.3
 29000 -25.7 -14.3  275  16  8   7.9   4.4 | -25.4 -13.7  275  18  9   7.9   4.4
 28000 -23.5 -10.3  265  13  7   6.4   3.5 | -23.1  -9.6  270  15  8   6.9   3.8
 27000 -21.6  -6.9  265  12  6   6.5   3.5 | -20.7  -5.3  270  12  6   6.5   3.5
 26000 -19.7  -3.5  265  11  6   6.5   3.6 | -18.9  -2.0  270  10  5   6.5   3.6
 25000 -17.8  -0.0  265  10  5   6.4   3.5 | -17.0   1.4  270   8  4   6.3   3.4
 24000 -15.9   3.4  275   7  4   6.2   3.4 | -15.2   4.6  270   6  3   6.0   3.3
 23000 -14.1   6.6  285   4  2   6.2   3.4 | -13.4   7.9  280   4  2   6.1   3.3
 22000 -12.3   9.9  330   3  1   5.7   3.1 | -11.7  10.9  300   2  1   5.7   3.1
 21000 -10.9  12.4  045   4  2   4.7   2.6 | -10.1  13.8  040   3  2   5.4   3.0
 20000  -9.5  14.9  065   9  4   4.7   2.6 |  -8.5  16.7  060   7  4   5.4   3.0
 19500  -8.8  16.2  070  11  6   4.5   2.5 |  -7.7  18.1  060   9  5   5.4   3.0
 19000  -7.9  17.8  075  12  6   6.8   3.7 |  -6.8  19.8  070  10  5   6.7   3.7
 18500  -7.0  19.4  085  11  6   6.7   3.7 |  -5.8  21.6  080   9  5   6.6   3.6
 18000  -6.0  21.2  095  11  6   8.2   4.5 |  -4.8  23.4  095   9  5   7.2   3.9
 17500  -4.5  23.9  100  10  5  10.0   5.5 |  -3.7  25.3  100   8  4   7.5   4.1
 17000  -3.0  26.6  105   9  5  10.1   5.6 |  -2.6  27.3  110   7  4   7.6   4.2
 16500  -1.6  29.1  115   8  4   8.9   4.9 |  -1.5  29.3  120   6  3   7.8   4.3
 16000   0.3  32.5  130   7  3   9.0   5.0 |  -0.4  31.3  125   5  3   7.7   4.2
 15500   1.6  34.9  140   6  3   8.3   4.6 |   0.8  33.4  125   4  2   8.2   4.5
 15000   2.8  37.0  155   7  3   8.3   4.6 |   2.0  35.6  110   4  2   8.3   4.5
 14500   4.1  39.4  160   6  3   8.5   4.7 |   3.2  37.8  100   5  2   8.4   4.6
 14000   5.4  41.7  160   6  3   8.5   4.7 |   5.2  41.4  085   5  3   8.6   4.7
 13500   6.8  44.2  160   5  2   9.1   5.0 |   6.5  43.7  080   6  3   9.2   5.0
 13000   8.2  46.8  160   3  2   9.3   5.1 |   7.8  46.0  080   6  3   9.3   5.1
 12500   9.5  49.1  150   2  1   9.3   5.1 |   9.2  48.6  080   6  3   9.6   5.2
 12000  10.9  51.6  155   2  1   9.3   5.1 |  10.5  50.9  085   6  3   9.2   5.0
 11750  11.6  52.9  155   1  1   9.0   4.9 |  11.1  52.0  085   6  3   8.7   4.8
 11500  12.2  54.0  160   1  1  10.0   5.5 |  11.7  53.1  085   6  3  10.3   5.7
 11250  13.0  55.4  165   1  1   9.4   5.2 |  12.5  54.5  085   6  3  10.4   5.7
 11000  13.6  56.5  150   1  1   8.1   4.4 |  13.2  55.8  090   6  3   9.0   4.9
 10750  14.2  57.6  140   1  1   8.4   4.6 |  13.8  56.8  090   6  3   9.3   5.1
 10500  14.8  58.6  130   1  1   8.7   4.8 |  14.5  58.1  090   6  3   9.4   5.2
 10250  15.4  59.7  120   1  1   9.5   5.2 |  15.2  59.4  095   6  3   9.6   5.3
 10000  16.1  61.0  105   1  1   8.4   4.6 |  15.8  60.4  095   6  3   9.8   5.4
  9750  16.6  61.9  085   2  1   7.5   4.1 |  16.6  61.9  100   6  3   9.9   5.4
  9500  17.2  63.0  075   2  1   7.8   4.3 |  17.3  63.1  100   6  3   9.7   5.3
  9250  17.7  63.9  060   2  1   7.7   4.2 |  18.0  64.4  100   6  3   9.4   5.1
  9000  18.3  64.9  055   2  1   7.9   4.4 |  18.7  65.7  100   6  3   9.7   5.3
  8750  18.9  66.0  040   2  1   8.7   4.8 |  19.4  66.9  100   6  3  10.8   5.9
  8500  19.5  67.1  020   3  1   8.6   4.7 |  20.2  68.4  105   5  3  10.8   5.9
  8250  20.1  68.2  010   3  1   8.2   4.5 |  21.0  69.8  105   5  3  10.4   5.7
  8000  20.6  69.1  355   3  1   8.2   4.5 |  21.8  71.2  105   5  3  10.3   5.6
  7750  21.1  70.0  345   3  1   8.8   4.9 |  22.6  72.7  110   5  3  11.0   6.0
  7500  21.8  71.2  335   2  1   9.4   5.1 |  23.4  74.1  110   5  3  12.3   6.8
  7250  22.3  72.1  335   2  1   9.1   5.0 |  24.3  75.7  110   5  3  12.6   6.9
  7000  22.8  73.0  335   1  1   9.6   5.3 |  25.2  77.4  110   5  3  12.5   6.8
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/02/2015 at 1500 MDT          |       08/02/2015 at 1800 MDT
                                           |
K index... +28.3  LI... +271.2             | K index... +29.3  LI... +272.2
CAPE... +119.2  CIN... -8.4                | CAPE... +38.7  CIN... -13.9
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.3 -87.3  290  35 18   1.8   1.0 | -65.5 -85.9  295  35 18   2.6   1.4
 45000 -61.7 -79.1  275  48 25   5.7   3.1 | -60.5 -76.9  280  45 23   4.8   2.6
 40000 -52.1 -61.8  250  61 31   8.3   4.5 | -51.8 -61.2  250  45 23   9.1   5.0
 38000 -47.1 -52.8  255  50 26   8.3   4.5 | -46.3 -51.3  245  39 20   9.1   5.0
 36000 -42.2 -44.0  265  40 21   8.4   4.6 | -40.8 -41.4  245  33 17   8.6   4.7
 34000 -37.0 -34.6  270  32 17   8.6   4.7 | -36.0 -32.8  245  26 13   8.0   4.4
 32000 -31.9 -25.4  280  25 13   9.5   5.2 | -31.3 -24.3  245  20 10   9.1   5.0
 30000 -27.4 -17.3  275  18  9   7.4   4.1 | -27.2 -17.0  225   9  4   6.8   3.7
 29000 -25.2 -13.4  275  15  8   7.4   4.1 | -24.7 -12.5  160   5  2   6.8   3.7
 28000 -22.6  -8.7  270  10  5   6.6   3.6 | -22.6  -8.7  115   7  4   7.0   3.8
 27000 -20.6  -5.1  280   7  3   6.7   3.7 | -20.6  -5.1  110   8  4   7.0   3.8
 26000 -18.6  -1.5  310   3  2   6.7   3.7 | -18.5  -1.3  100  10  5   7.0   3.9
 25000 -16.7   1.9  025   3  2   6.3   3.5 | -16.5   2.3  095  11  6   6.7   3.7
 24000 -14.9   5.2  055   5  2   6.0   3.3 | -14.6   5.7  105  11  6   6.3   3.4
 23000 -13.2   8.2  070   7  3   6.0   3.3 | -12.8   9.0  110  12  6   6.3   3.5
 22000 -11.4  11.5  075   9  5   5.9   3.3 | -11.0  12.2  120  12  6   6.2   3.4
 21000  -9.7  14.5  080   9  5   5.9   3.2 |  -9.2  15.4  125  13  6   6.1   3.3
 20000  -8.0  17.6  080   9  5   5.9   3.2 |  -7.5  18.5  130  13  7   6.1   3.4
 19500  -7.2  19.0  080   9  5   5.9   3.3 |  -6.6  20.1  135  13  7   6.2   3.4
 19000  -6.2  20.8  080   9  5   6.8   3.7 |  -5.7  21.7  135  14  7   5.6   3.0
 18500  -5.2  22.6  085   9  5   6.7   3.7 |  -4.9  23.2  140  14  7   5.6   3.1
 18000  -4.3  24.3  085   9  4   6.8   3.7 |  -4.1  24.6  145  14  7   5.6   3.1
 17500  -3.3  26.1  090   9  5   6.8   3.7 |  -3.3  26.1  145  14  7   5.6   3.1
 17000  -2.3  27.9  095  10  5   6.8   3.7 |  -2.5  27.5  150  13  7   5.6   3.1
 16500  -1.3  29.7  100  10  5   6.8   3.8 |  -1.7  28.9  150  13  7   5.6   3.0
 16000  -0.3  31.5  100   9  5   6.8   3.7 |  -1.0  30.2  155  12  6   5.6   3.1
 15500   0.7  33.3  105   9  5   7.4   4.1 |  -0.2  31.6  155  12  6   5.1   2.8
 15000   1.8  35.2  110   8  4   7.6   4.2 |   0.5  32.9  160  11  6   5.0   2.7
 14500   2.9  37.2  120   8  4   8.1   4.4 |   1.8  35.2  170  10  5   7.8   4.3
 14000   4.8  40.6  125   8  4   8.7   4.8 |   2.9  37.2  170  10  5   8.0   4.4
 13500   6.1  43.0  125   8  4   9.5   5.2 |   4.1  39.4  175   9  5   8.4   4.6
 13000   7.5  45.5  130   8  4   9.8   5.4 |   5.3  41.5  175   9  5   8.6   4.7
 12500   8.8  47.8  135   9  4   9.3   5.1 |   6.6  43.9  180   9  5   9.0   4.9
 12000  10.3  50.5  135   9  4   9.9   5.4 |   7.9  46.2  180   9  5   8.7   4.8
 11750  11.0  51.8  135   9  4   9.5   5.2 |   8.6  47.5  180   9  5   8.2   4.5
 11500  11.7  53.1  140   9  5  10.9   6.0 |   9.2  48.6  180   9  5  10.3   5.7
 11250  12.6  54.7  140   9  4  10.5   5.8 |  10.0  50.0  180   9  4  10.3   5.6
 11000  13.3  55.9  140   9  5   8.9   4.9 |  10.6  51.1  180   9  4   8.0   4.4
 10750  13.9  57.0  140   9  5   9.1   5.0 |  11.2  52.2  180   9  5   8.2   4.5
 10500  14.6  58.3  145   9  5   9.8   5.4 |  11.8  53.2  180   9  5   8.7   4.8
 10250  15.4  59.7  145   9  5  10.8   5.9 |  12.5  54.5  175   9  4   9.7   5.3
 10000  16.2  61.2  145   9  5   9.9   5.4 |  13.2  55.8  175   8  4   9.2   5.0
  9750  16.9  62.4  145   9  5   9.3   5.1 |  13.9  57.0  175   8  4   8.7   4.8
  9500  17.6  63.7  145   9  5   9.6   5.3 |  14.5  58.1  175   8  4   8.8   4.9
  9250  18.3  64.9  150   9  5   9.6   5.3 |  15.2  59.4  170   8  4   8.7   4.8
  9000  19.0  66.2  150   9  5   9.9   5.4 |  15.8  60.4  170   8  4   9.0   4.9
  8750  19.8  67.6  150   9  5  10.6   5.8 |  16.6  61.9  170   8  4  10.4   5.7
  8500  20.6  69.1  150   9  5  10.7   5.9 |  17.3  63.1  165   8  4  10.1   5.6
  8250  21.4  70.5  150   9  5  10.5   5.8 |  18.0  64.4  160   7  4   9.2   5.1
  8000  22.2  72.0  155   9  5  10.6   5.8 |  18.7  65.7  155   7  4   9.3   5.1
  7750  22.9  73.2  155   9  5  10.5   5.8 |  19.4  66.9  150   7  3   9.9   5.4
  7500  23.7  74.7  155   9  5  11.5   6.3 |  20.1  68.2  145   6  3   7.7   4.2
  7250  24.6  76.3  155   9  5  12.4   6.8 |  20.5  68.9  140   6  3   4.9   2.7
  7000  25.4  77.7  150   9  5  11.7   6.4 |  20.8  69.4  135   5  2   7.1   3.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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