Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 180950
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0350 MDT Friday, July 18, 2014

This forecast is for Friday, July 18, 2014:

If the trigger temperature of 72.9 F/22.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1056 ft/min (5.4 m/s)
   Maximum height of thermals.................. 17951 ft MSL (11193 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 0945 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................. 14422 ft MSL (7665 ft AGL)
Thermal soaring outlook for Saturday 07/19..... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Neutral
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15618 ft MSL (8860 ft AGL)
Wave soaring outlook for Saturday 07/19........ Poor

Remarks...

Sunrise/Sunset.................... 05:48:14 / 20:22:24 MDT
Total possible sunshine........... 14 hr 34 min 10 sec (874 min 10 sec)
Altitude of sun at 13:05:13 MDT... 71.95 degrees

Upper air data from numerical model forecast valid on 07/18/2014 at 0600 MDT

Freezing level.................. 15321 ft MSL (8563 ft AGL)
Convective condensation level... 14159 ft MSL (7401 ft AGL)
Lifted condensation level....... 15117 ft MSL (8359 ft AGL)
Lifted index.................... -4.0
K index......................... +19.6

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  -63.9 -83.0   300   22   11   1.3   0.7      M     M       M      M    M
 45000  -60.3 -76.5   300   33   17   4.5   2.5      M     M       M      M    M
 40000  -53.4 -64.1   310   37   19   6.0   3.3      M     M       M      M    M
 38000  -49.7 -57.5   305   33   17   6.1   3.3      M     M       M      M    M
 36000  -46.1 -51.0   300   29   15   5.9   3.2      M     M       M      M    M
 34000  -41.3 -42.3   300   26   13   8.3   4.5      M     M       M      M    M
 32000  -36.3 -33.3   300   23   12   8.2   4.5      M     M       M      M    M
 30000  -30.8 -23.4   300   22   11   8.3   4.5   38.8 101.8     9.0      M    M
 29000  -28.3 -18.9   295   22   11   8.3   4.5   38.3 100.9     8.7      M    M
 28000  -25.8 -14.4   300   21   11   8.1   4.5   37.8 100.1     8.4      M    M
 27000  -23.4 -10.1   305   21   11   8.1   4.4   37.1  98.8     7.9      M    M
 26000  -21.0  -5.8   310   20   10   8.1   4.4   36.5  97.6     7.5      M    M
 25000  -18.6  -1.5   315   20   10   7.9   4.3   36.0  96.7     7.2      M    M
 24000  -16.5   2.3   315   19   10   6.5   3.6   34.8  94.7     6.3      M    M
 23000  -14.5   5.9   320   19   10   6.5   3.6   33.6  92.6     5.4      M    M
 22000  -12.6   9.3   325   19   10   6.4   3.5   32.6  90.7     4.6      M    M
 21000  -10.8  12.6   320   17    9   6.0   3.3   31.3  88.3     3.5      M    M
 20000   -9.0  15.8   315   15    8   6.0   3.3   30.0  85.9     2.4      M    M
 19500   -8.1  17.4   310   14    7   6.1   3.3   29.4  84.9     1.9      M    M
 19000   -7.2  19.0   310   13    7   6.0   3.3   28.8  83.8     1.3      M    M
 18500   -6.3  20.7   310   12    6   6.1   3.3   28.1  82.6     0.7      M    M
 18000   -5.4  22.3   310   12    6   6.0   3.3   27.5  81.5     0.2      M    M
 17500   -4.6  23.7   310   12    6   5.9   3.2   26.9  80.4    -0.5   1027  5.2
 17000   -3.8  25.2   310   13    7   6.0   3.3   26.2  79.2    -1.1    987  5.0
 16500   -2.9  26.8   310   14    7   7.4   4.1   25.7  78.3    -1.7    946  4.8
 16000   -1.8  28.8   310   15    8   7.6   4.2   25.3  77.6    -2.2    900  4.6
 15500   -0.8  30.6   305   16    8   8.4   4.6   25.0  77.0    -2.6    853  4.3
 15000    1.2  34.2   300   16    8   9.2   5.0   24.8  76.7    -2.8    772  3.9
 14500    2.5  36.5   300   16    8   9.1   5.0   24.7  76.5    -3.0    719  3.7
 14000    3.8  38.8   300   15    7   9.2   5.1   24.6  76.4    -3.2    665  3.4
 13500    5.0  41.0   300   13    7   9.2   5.1   24.6  76.2    -3.4    612  3.1
 13000    6.4  43.5   295   12    6   9.2   5.0   24.5  76.1    -3.6    557  2.8
 12500    7.7  45.9   295   11    6   8.3   4.6   24.4  75.9    -3.7    502  2.6
 12000    8.9  48.0   295    9    5   9.4   5.1   24.2  75.5    -3.9    451  2.3
 11750    9.6  49.3   295    9    4   9.1   5.0   24.1  75.5    -4.0    423  2.2
 11500   10.3  50.5   295    8    4   9.2   5.0   24.1  75.4    -4.1    396  2.0
 11250   10.9  51.6   295    7    4   8.9   4.9   24.1  75.3    -4.2    369  1.9
 11000   11.6  52.9   290    7    4   8.7   4.8   24.0  75.2    -4.3    343  1.7
 10750   12.2  54.0   290    7    3   9.0   4.9   23.9  75.0    -4.4    316  1.6
 10500   12.8  55.0   290    6    3   8.3   4.5   23.8  74.9    -4.5    290  1.5
 10250   13.4  56.1   285    6    3   6.4   3.5   23.6  74.6    -4.7    266  1.4
 10000   13.8  56.8   280    6    3   7.3   4.0   23.4  74.1    -5.0    246  1.2
  9750   14.4  57.9   275    6    3   9.1   5.0   23.3  73.9    -5.1    220  1.1
  9500   15.0  59.0   270    5    3   7.5   4.1   23.2  73.8    -5.3    195  1.0
  9250   15.5  59.9   265    5    3   5.3   2.9   22.9  73.3    -5.6    174  0.9
  9000   15.8  60.4   255    6    3   4.8   2.6   22.6  72.6    -6.0    156  0.8
  8750   16.2  61.2   255    6    3   7.0   3.8   22.3  72.1    -6.3    137  0.7
  8500   16.7  62.1   260    8    4   3.8   2.1   22.0  71.6    -6.6    116  0.6
  8250   16.6  61.9   260    8    4  -1.4  -0.8   21.3  70.3    -7.4    110  0.6
  8000   16.4  61.5   260    9    5  -1.6  -0.9   20.5  68.8    -8.3    108  0.5
  7750   16.3  61.3   260    9    5  -0.6  -0.3   19.6  67.3    -9.2    105  0.5
  7500   15.9  60.6   250   10    5 -10.7  -5.8   18.7  65.6   -10.3    109  0.6
  7250   14.6  58.3   250    8    4 -20.9 -11.5   17.0  62.6   -12.0    142  0.7
  7000   13.2  55.8   250    7    3 -13.1  -7.2   15.3  59.6   -13.7    174  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/18/2014 at 0900 MDT          |       07/18/2014 at 1200 MDT
                                           |
K index... +10.2  LI... -1.8               | K index... +20.9  LI... -1.2
CAPE... +533.5  CIN... -34.6               | CAPE... +121.6  CIN... -9.1
                                           |
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 -64.2 -83.6  285  22 11   1.4   0.8 | -63.9 -83.0  280  28 14   0.7   0.4
 45000 -60.6 -77.1  295  36 18   4.5   2.5 | -61.1 -78.0  285  40 20   4.5   2.4
 40000 -53.4 -64.1  305  39 20   7.1   3.9 | -53.8 -64.8  290  44 22   7.9   4.3
 38000 -49.0 -56.2  305  38 20   7.2   3.9 | -49.0 -56.2  295  44 23   8.0   4.4
 36000 -44.7 -48.5  305  38 20   7.2   3.9 | -44.3 -47.7  300  45 23   8.0   4.4
 34000 -40.2 -40.4  305  35 18   7.5   4.1 | -39.8 -39.6  300  42 22   7.4   4.1
 32000 -35.1 -31.2  310  31 16   7.8   4.3 | -34.8 -30.6  300  37 19   7.7   4.2
 30000 -30.7 -23.3  310  28 14   7.5   4.1 | -30.4 -22.7  300  34 17   7.2   4.0
 29000 -28.5 -19.3  310  27 14   7.5   4.1 | -28.3 -18.9  300  32 16   7.2   4.0
 28000 -26.2 -15.2  310  25 13   7.8   4.3 | -26.1 -15.0  300  30 16   7.5   4.1
 27000 -23.9 -11.0  305  23 12   7.9   4.3 | -23.8 -10.8  300  30 15   7.6   4.2
 26000 -21.5  -6.7  305  22 11   7.9   4.3 | -21.6  -6.9  295  29 15   7.6   4.2
 25000 -19.1  -2.4  300  20 10   7.8   4.3 | -19.3  -2.7  295  29 15   7.6   4.2
 24000 -16.9   1.6  305  19 10   7.4   4.1 | -17.0   1.4  295  29 15   7.8   4.3
 23000 -14.6   5.7  310  19 10   7.4   4.1 | -14.7   5.5  295  29 15   7.8   4.3
 22000 -12.4   9.7  315  19 10   7.2   4.0 | -12.4   9.7  300  28 15   7.2   4.0
 21000 -10.4  13.3  320  18  9   6.6   3.6 | -10.6  12.9  305  25 13   5.8   3.2
 20000  -8.4  16.9  320  17  9   6.6   3.6 |  -8.9  16.0  310  22 11   5.8   3.2
 19500  -7.4  18.7  320  17  9   6.7   3.7 |  -8.1  17.4  310  20 10   5.7   3.1
 19000  -6.5  20.3  320  16  8   5.5   3.0 |  -7.2  19.0  315  19 10   6.9   3.8
 18500  -5.7  21.7  320  16  8   5.5   3.0 |  -6.2  20.8  315  18  9   6.9   3.8
 18000  -4.8  23.4  320  15  8   5.3   2.9 |  -5.2  22.6  320  17  9   7.0   3.8
 17500  -4.1  24.6  325  15  8   5.1   2.8 |  -4.1  24.6  325  16  8   7.2   3.9
 17000  -3.4  25.9  325  16  8   5.1   2.8 |  -3.1  26.4  330  16  8   7.2   3.9
 16500  -2.6  27.3  330  16  8   7.0   3.9 |  -2.0  28.4  335  16  8   7.4   4.1
 16000  -1.6  29.1  330  16  8   7.1   3.9 |  -1.0  30.2  340  16  8   7.4   4.1
 15500   0.0  32.0  335  17  9   8.6   4.7 |   0.7  33.3  340  15  8   8.2   4.5
 15000   1.3  34.3  335  17  9   8.4   4.6 |   1.8  35.2  340  15  8   8.2   4.5
 14500   2.5  36.5  335  17  9   9.4   5.2 |   3.0  37.4  340  14  7   9.4   5.1
 14000   3.9  39.0  335  17  9   9.6   5.3 |   4.4  39.9  335  14  7   9.5   5.2
 13500   5.4  41.7  335  17  9   9.6   5.2 |   5.8  42.4  335  13  7   9.8   5.4
 13000   6.7  44.1  335  16  8   9.5   5.2 |   7.2  45.0  335  13  7   9.9   5.5
 12500   8.1  46.6  330  15  8   9.0   5.0 |   8.7  47.7  335  13  7   9.2   5.1
 12000   9.5  49.1  330  15  8   9.6   5.3 |  10.1  50.2  335  12  6   9.9   5.4
 11750  10.2  50.4  330  14  7   9.6   5.3 |  10.8  51.4  335  12  6  10.0   5.5
 11500  10.8  51.4  330  14  7   9.0   4.9 |  11.6  52.9  335  12  6   9.1   5.0
 11250  11.5  52.7  330  13  7   8.9   4.9 |  12.2  54.0  335  11  6   9.3   5.1
 11000  12.1  53.8  325  12  6   9.4   5.2 |  13.0  55.4  335  11  6  10.4   5.7
 10750  12.8  55.0  325  11  6   9.5   5.2 |  13.7  56.7  335  11  6  10.3   5.6
 10500  13.5  56.3  320  10  5   8.9   4.9 |  14.5  58.1  335  11  5   9.6   5.2
 10250  14.0  57.2  315  10  5   7.3   4.0 |  15.1  59.2  335  10  5   8.1   4.5
 10000  14.6  58.3  310   9  5   8.5   4.7 |  15.7  60.3  335  10  5   9.5   5.2
  9750  15.2  59.4  305   8  4  10.2   5.6 |  16.5  61.7  335   9  5  10.9   6.0
  9500  15.9  60.6  295   8  4   8.9   4.9 |  17.3  63.1  335   9  5  10.1   5.5
  9250  16.5  61.7  290   8  4   7.3   4.0 |  18.0  64.4  335   9  4   9.1   5.0
  9000  17.0  62.6  280   8  4   6.9   3.8 |  18.7  65.7  335   8  4   9.5   5.2
  8750  17.5  63.5  280   8  4   7.3   4.0 |  19.4  66.9  335   8  4  10.9   6.0
  8500  18.0  64.4  275   8  4   6.7   3.7 |  20.3  68.5  335   8  4  10.9   6.0
  8250  18.3  64.9  275   8  4   6.1   3.4 |  21.0  69.8  335   7  4  10.2   5.6
  8000  18.7  65.7  270   8  4   5.3   2.9 |  21.8  71.2  335   7  3  10.2   5.6
  7750  19.0  66.2  265   7  4   8.9   4.9 |  22.6  72.7  335   6  3  10.6   5.8
  7500  19.7  67.5  255   6  3   9.4   5.2 |  23.4  74.1  335   6  3  11.6   6.4
  7250  20.1  68.2  250   6  3   5.5   3.0 |  24.2  75.6  335   6  3  12.1   6.6
  7000  20.6  69.1  245   6  3   8.8   4.8 |  25.0  77.0  335   5  3  11.8   6.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/18/2014 at 1500 MDT          |       07/18/2014 at 1800 MDT
                                           |
K index... +28.4  LI... -1.5               | K index... +24.5  LI... -1.3
CAPE... +111.2  CIN... -11.3               | CAPE... +108.6  CIN... -24.1
                                           |
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 -64.1 -83.4  285  31 16   0.6   0.3 | -64.2 -83.6  280  32 17   0.7   0.4
 45000 -61.5 -78.7  285  46 24   4.3   2.4 | -61.2 -78.2  285  45 23   4.9   2.7
 40000 -54.3 -65.7  280  47 24   8.1   4.5 | -53.5 -64.3  280  51 26   7.1   3.9
 38000 -49.4 -56.9  285  47 24   8.2   4.5 | -49.2 -56.6  285  49 25   7.1   3.9
 36000 -44.4 -47.9  285  46 24   8.3   4.5 | -44.9 -48.8  285  47 24   7.0   3.9
 34000 -39.8 -39.6  290  42 22   7.7   4.2 | -40.2 -40.4  285  46 24   8.0   4.4
 32000 -34.6 -30.3  290  37 19   8.2   4.5 | -34.8 -30.6  290  45 23   8.5   4.6
 30000 -30.0 -22.0  290  34 17   7.7   4.2 | -30.0 -22.0  290  41 21   8.0   4.4
 29000 -27.8 -18.0  290  32 17   7.7   4.2 | -27.6 -17.7  290  39 20   8.0   4.4
 28000 -25.5 -13.9  295  31 16   7.4   4.1 | -25.2 -13.4  290  37 19   7.3   4.0
 27000 -23.3  -9.9  295  32 17   7.4   4.1 | -23.0  -9.4  295  36 18   7.3   4.0
 26000 -21.1  -6.0  295  33 17   7.4   4.1 | -20.9  -5.6  295  34 18   7.3   4.0
 25000 -18.9  -2.0  300  34 17   7.3   4.0 | -18.8  -1.8  295  33 17   7.1   3.9
 24000 -16.9   1.6  295  32 17   6.9   3.8 | -16.9   1.6  300  31 16   6.3   3.5
 23000 -14.8   5.4  290  30 16   6.9   3.8 | -15.0   5.0  300  28 15   6.4   3.5
 22000 -12.8   9.0  285  29 15   6.7   3.6 | -13.1   8.4  300  26 14   6.6   3.6
 21000 -11.0  12.2  285  25 13   6.1   3.4 | -11.1  12.0  300  26 13   7.0   3.8
 20000  -9.2  15.4  285  21 11   6.2   3.4 |  -9.0  15.8  300  25 13   7.0   3.8
 19500  -8.3  17.1  285  19 10   6.2   3.4 |  -8.0  17.6  300  25 13   6.9   3.8
 19000  -7.4  18.7  285  17  9   6.2   3.4 |  -7.0  19.4  300  25 13   7.5   4.1
 18500  -6.5  20.3  285  15  8   6.2   3.4 |  -5.9  21.4  295  25 13   7.4   4.1
 18000  -5.6  21.9  290  14  7   6.4   3.5 |  -4.8  23.4  290  25 13   7.3   4.0
 17500  -4.7  23.5  290  12  6   6.7   3.7 |  -3.7  25.3  290  24 13   7.2   3.9
 17000  -3.7  25.3  295  10  5   6.6   3.6 |  -2.7  27.1  290  23 12   7.2   3.9
 16500  -2.6  27.3  300   9  5   7.8   4.3 |  -1.6  29.1  285  22 12   7.6   4.2
 16000  -0.9  30.4  315   8  4   7.8   4.3 |   0.0  32.0  285  21 11   7.6   4.2
 15500   0.3  32.5  325   8  4   9.6   5.3 |   1.2  34.2  285  19 10   8.2   4.5
 15000   1.7  35.1  330   8  4   9.5   5.2 |   2.3  36.1  285  16  8   8.2   4.5
 14500   3.2  37.8  335   8  4   9.7   5.3 |   3.6  38.5  290  14  7   9.0   4.9
 14000   4.6  40.3  340   9  4   9.7   5.3 |   4.9  40.8  290  13  7   9.0   4.9
 13500   6.0  42.8  340   9  5   9.7   5.3 |   6.3  43.3  290  12  6   9.1   5.0
 13000   7.5  45.5  345  10  5   9.9   5.4 |   7.6  45.7  290  11  6   9.0   4.9
 12500   8.9  48.0  350  11  5   8.6   4.7 |   9.0  48.2  295  11  6   9.3   5.1
 12000  10.2  50.4  355  12  6   9.3   5.1 |  10.3  50.5  305  10  5   8.8   4.8
 11750  10.9  51.6  355  12  6   8.9   4.9 |  10.9  51.6  305  10  5   8.2   4.5
 11500  11.6  52.9  355  13  7  10.6   5.8 |  11.6  52.9  310   9  5  10.1   5.5
 11250  12.4  54.3  355  13  7  10.6   5.8 |  12.4  54.3  315  10  5   9.5   5.2
 11000  13.1  55.6  355  13  7   8.7   4.8 |  12.9  55.2  325  10  5   7.3   4.0
 10750  13.8  56.8  355  14  7   9.1   5.0 |  13.5  56.3  330  10  5   7.7   4.2
 10500  14.4  57.9  360  14  7   9.3   5.1 |  14.0  57.2  335  10  5   8.2   4.5
 10250  15.1  59.2  360  14  7   9.8   5.4 |  14.7  58.5  340  10  5   9.1   5.0
 10000  15.9  60.6  355  14  7   9.7   5.3 |  15.3  59.5  340  10  5   9.5   5.2
  9750  16.6  61.9  360  14  7   9.7   5.3 |  16.1  61.0  345  10  5   9.8   5.4
  9500  17.3  63.1  360  15  7   9.3   5.1 |  16.8  62.2  350  10  5   9.5   5.2
  9250  18.0  64.4  360  15  7   8.5   4.7 |  17.5  63.5  350  10  5   9.0   4.9
  9000  18.6  65.5  360  14  7   9.0   5.0 |  18.1  64.6  350   9  5   9.3   5.1
  8750  19.3  66.7  360  14  7  11.1   6.1 |  18.9  66.0  350   9  5  10.3   5.7
  8500  20.2  68.4  360  14  7  10.8   5.9 |  19.6  67.3  350   9  5  10.5   5.7
  8250  20.9  69.6  360  14  7   9.5   5.2 |  20.4  68.7  350   9  5  10.0   5.5
  8000  21.6  70.9  360  14  7   9.7   5.3 |  21.1  70.0  350   9  5  10.3   5.6
  7750  22.3  72.1  360  14  7   9.9   5.4 |  21.9  71.4  350   9  5   9.7   5.3
  7500  23.0  73.4  360  14  7   7.7   4.2 |  22.5  72.5  350   9  4   8.1   4.5
  7250  23.4  74.1  360  12  6   5.5   3.0 |  23.1  73.6  350   8  4   7.5   4.1
  7000  23.8  74.8  360  11  6   7.3   4.0 |  23.6  74.5  350   8  4   8.0   4.4
  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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