Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 161037
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0437 MDT Tuesday, September 16, 2014

This forecast is for Tuesday, September 16, 2014:

If the trigger temperature of 73.0 F/22.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1483 ft/min (7.5 m/s)
   Maximum height of thermals.................. 19607 ft MSL (12849 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1030 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................. 11427 ft MSL (4669 ft AGL)
Thermal soaring outlook for Wednesday 09/17.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Good
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 46276 ft MSL (39518 ft AGL)
Wave soaring outlook for Wednesday 09/17....... Good

Remarks...

Sunrise/Sunset.................... 06:41:18 / 19:07:08 MDT
Total possible sunshine........... 12 hr 25 min 50 sec (745 min 50 sec)
Altitude of sun at 12:53:44 MDT... 53.51 degrees

Upper air data from numerical model forecast valid on 09/16/2014 at 0600 MDT

Freezing level.................. 15214 ft MSL (8456 ft AGL)
Convective condensation level... 15569 ft MSL (8811 ft AGL)
Lifted condensation level....... 16000 ft MSL (9242 ft AGL)
Lifted index.................... -2.7
K index......................... +28.2

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  -66.4 -87.5   295   52   27   2.4   1.3      M     M       M      M    M
 45000  -61.6 -78.9   290   72   37   5.3   2.9      M     M       M      M    M
 40000  -53.1 -63.6   290   60   31   6.6   3.6      M     M       M      M    M
 38000  -49.2 -56.6   295   54   28   6.6   3.6      M     M       M      M    M
 36000  -45.2 -49.4   300   49   25   6.7   3.7      M     M       M      M    M
 34000  -41.6 -42.9   300   42   22   6.0   3.3      M     M       M      M    M
 32000  -38.0 -36.4   300   35   18   6.0   3.3      M     M       M      M    M
 30000  -33.3 -27.9   300   31   16   8.3   4.6   36.6  97.9     8.1      M    M
 29000  -30.8 -23.4   300   29   15   8.4   4.6   36.1  97.0     7.8      M    M
 28000  -28.4 -19.1   300   27   14   8.3   4.6   35.7  96.3     7.6      M    M
 27000  -25.2 -13.4   295   25   13   8.3   4.6   34.9  94.9     7.1      M    M
 26000  -22.7  -8.9   295   23   12   8.3   4.6   34.4  93.9     6.8      M    M
 25000  -20.2  -4.4   295   22   11   7.5   4.1   34.0  93.2     6.5      M    M
 24000  -18.6  -1.5   300   21   11   5.2   2.9   32.4  90.2     5.2      M    M
 23000  -17.1   1.2   300   20   10   5.3   2.9   30.7  87.3     3.8      M    M
 22000  -15.6   3.9   305   19   10   5.8   3.2   29.3  84.7     2.6      M    M
 21000  -13.7   7.3   300   17    9   6.5   3.6   28.0  82.5     1.4      M    M
 20000  -11.9  10.6   300   16    8   6.6   3.6   27.0  80.5     0.4      M    M
 19500  -10.9  12.4   300   15    8   6.6   3.6   26.5  79.6    -0.1   1276  6.5
 19000   -9.8  14.4   295   14    7   8.7   4.8   26.1  79.0    -0.4   1228  6.2
 18500   -8.6  16.5   295   13    7   8.5   4.7   25.9  78.6    -0.7   1177  6.0
 18000   -7.4  18.7   295   13    6   8.7   4.8   25.7  78.3    -0.9   1125  5.7
 17500   -6.1  21.0   295   13    6   8.9   4.9   25.6  78.0    -1.1   1072  5.4
 17000   -4.8  23.4   295   13    6   9.0   4.9   25.4  77.8    -1.3   1018  5.2
 16500   -3.5  25.7   290   12    6   8.6   4.7   25.3  77.5    -1.5    965  4.9
 16000   -2.3  27.9   290   12    6   8.6   4.7   25.1  77.1    -1.7    913  4.6
 15500   -1.0  30.2   290   12    6   8.8   4.8   24.9  76.8    -1.9    860  4.4
 15000    0.3  32.5   290   12    6   8.9   4.9   24.8  76.6    -2.0    806  4.1
 14500    1.6  34.9   290   12    6   9.2   5.0   24.6  76.3    -2.2    752  3.8
 14000    3.0  37.4   290   12    6   9.5   5.2   24.6  76.2    -2.2    695  3.5
 13500    5.1  41.2   290   13    7   9.0   5.0   24.5  76.1    -2.3    611  3.1
 13000    6.4  43.5   290   13    7   9.0   5.0   24.4  75.9    -2.5    556  2.8
 12500    7.7  45.9   285   14    7   8.2   4.5   24.2  75.6    -2.7    504  2.6
 12000    9.0  48.2   285   15    7   9.3   5.1   24.1  75.3    -2.9    450  2.3
 11750    9.6  49.3   280   15    8   9.1   5.0   24.0  75.2    -2.9    423  2.1
 11500   10.3  50.5   280   15    8   9.6   5.3   24.0  75.2    -3.0    395  2.0
 11250   11.0  51.8   280   15    8   9.2   5.0   24.0  75.2    -3.0    367  1.9
 11000   11.6  52.9   275   16    8   8.1   4.5   23.9  75.0    -3.1    341  1.7
 10750   12.2  54.0   275   16    8   8.3   4.6   23.8  74.8    -3.3    315  1.6
 10500   12.8  55.0   275   17    9   8.0   4.4   23.7  74.6    -3.4    290  1.5
 10250   13.4  56.1   275   17    9   7.8   4.3   23.5  74.3    -3.6    265  1.3
 10000   14.0  57.2   275   17    9   7.8   4.3   23.4  74.0    -3.7    241  1.2
  9750   14.6  58.3   270   17    9   8.5   4.7   23.2  73.8    -3.9    215  1.1
  9500   15.2  59.4   270   17    9   6.2   3.4   23.1  73.6    -4.0    190  1.0
  9250   15.5  59.9   270   16    8   3.8   2.1   22.7  72.8    -4.4    173  0.9
  9000   15.8  60.4   265   16    8   4.8   2.7   22.3  72.1    -4.9    156  0.8
  8750   16.3  61.3   265   16    8   8.1   4.4   22.0  71.6    -5.1    136  0.7
  8500   16.7  62.1   265   15    8   0.3   0.1   21.7  71.1    -5.4    115  0.6
  8250   16.2  61.2   260   15    7  -9.3  -5.1   20.5  68.9    -6.7    123  0.6
  8000   15.7  60.3   255   14    7  -1.8  -1.0   19.3  66.7    -8.0    132  0.7
  7750   15.1  59.2   250   14    7 -22.2 -12.2   18.1  64.5    -9.2    140  0.7
  7500   12.5  54.5   245   14    7 -29.5 -16.2   15.0  58.9   -12.4    211  1.1
  7250   11.3  52.3   245   11    6 -11.3  -6.2   13.3  56.0   -14.1    242  1.2
  7000   10.0  50.0   245    9    4 -26.7 -14.6   11.7  53.0   -15.8    272  1.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/16/2014 at 0900 MDT          |       09/16/2014 at 1200 MDT
                                           |
K index... +9.5  LI... -0.0                | K index... +15.7  LI... -0.7
CAPE... 0.0  CIN... M                      | CAPE... +20.0  CIN... -27.8
                                           |
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 -66.8 -88.2  290  52 27   2.4   1.3 | -66.8 -88.2  290  53 27   2.3   1.3
 45000 -62.0 -79.6  290  69 36   5.2   2.9 | -62.3 -80.1  290  68 35   4.5   2.5
 40000 -53.9 -65.0  290  56 29   6.7   3.7 | -55.2 -67.4  285  53 27   7.3   4.0
 38000 -49.9 -57.8  295  51 26   6.7   3.7 | -50.8 -59.4  295  48 25   7.3   4.0
 36000 -45.9 -50.6  305  46 24   6.7   3.7 | -46.4 -51.5  300  45 23   7.3   4.0
 34000 -41.4 -42.5  305  40 21   6.7   3.7 | -41.2 -42.2  305  40 21   7.8   4.3
 32000 -37.3 -35.1  305  35 18   6.5   3.6 | -36.5 -33.7  310  35 18   7.8   4.3
 30000 -32.6 -26.7  305  30 15   8.2   4.5 | -31.7 -25.1  305  29 15   7.9   4.3
 29000 -30.1 -22.2  305  28 14   8.2   4.5 | -29.4 -20.9  300  27 14   7.9   4.3
 28000 -27.7 -17.9  300  26 13   8.1   4.4 | -27.0 -16.6  300  24 12   7.9   4.3
 27000 -25.2 -13.4  300  24 12   8.1   4.4 | -24.6 -12.3  295  23 12   7.9   4.3
 26000 -22.8  -9.0  300  23 12   8.1   4.4 | -22.3  -8.1  295  22 11   7.9   4.3
 25000 -20.4  -4.7  295  21 11   7.9   4.3 | -19.9  -3.8  295  20 10   7.6   4.2
 24000 -18.4  -1.1  300  19 10   6.3   3.5 | -18.1  -0.6  290  18  9   5.8   3.2
 23000 -16.5   2.3  300  16  8   6.3   3.5 | -16.3   2.7  290  15  8   5.9   3.2
 22000 -14.6   5.7  305  14  7   6.1   3.4 | -14.6   5.7  285  13  7   5.8   3.2
 21000 -13.0   8.6  305  14  7   5.5   3.0 | -12.9   8.8  290  13  7   5.6   3.1
 20000 -11.3  11.7  305  13  7   5.5   3.0 | -11.3  11.7  295  14  7   5.6   3.1
 19500 -10.5  13.1  305  13  7   5.3   2.9 | -10.5  13.1  300  15  8   5.3   2.9
 19000  -9.5  14.9  305  13  7   8.0   4.4 |  -9.5  14.9  305  16  8   8.7   4.8
 18500  -8.4  16.9  305  14  7   7.8   4.3 |  -8.2  17.2  310  17  9   8.4   4.6
 18000  -7.2  19.0  305  14  7   8.0   4.4 |  -7.0  19.4  315  18  9   8.5   4.6
 17500  -6.0  21.2  310  14  7   8.3   4.6 |  -5.7  21.7  320  19 10   8.5   4.7
 17000  -4.8  23.4  310  15  7   8.3   4.6 |  -4.5  23.9  320  20 10   8.6   4.7
 16500  -2.9  26.8  310  14  7   8.8   4.8 |  -2.6  27.3  325  20 10   8.2   4.5
 16000  -1.6  29.1  310  14  7   8.8   4.8 |  -1.4  29.5  325  20 10   8.1   4.5
 15500  -0.3  31.5  315  14  7   9.1   5.0 |  -0.2  31.6  325  19 10   8.0   4.4
 15000   1.0  33.8  315  13  7   9.1   5.0 |   0.9  33.6  325  18  9   8.0   4.4
 14500   2.3  36.1  320  13  7   9.1   5.0 |   2.1  35.8  325  17  9   8.3   4.5
 14000   3.7  38.7  320  13  7   9.1   5.0 |   3.3  37.9  325  15  8   8.3   4.5
 13500   5.0  41.0  325  13  7   8.7   4.8 |   4.5  40.1  330  14  7   8.9   4.9
 13000   6.3  43.3  325  13  7   8.7   4.8 |   5.8  42.4  335  14  7   9.2   5.1
 12500   7.5  45.5  330  13  7   8.3   4.6 |   7.1  44.8  340  13  7   8.2   4.5
 12000   8.8  47.8  330  13  7   9.0   4.9 |   8.5  47.3  340  12  6  10.3   5.6
 11750   9.5  49.1  335  13  7   8.8   4.8 |   9.2  48.6  345  12  6  10.0   5.5
 11500  10.1  50.2  335  13  7   9.6   5.2 |  10.0  50.0  345  12  6  10.6   5.8
 11250  10.8  51.4  335  13  7   9.3   5.1 |  10.7  51.3  345  12  6  10.2   5.6
 11000  11.5  52.7  335  13  7   8.2   4.5 |  11.4  52.5  345  12  6   9.3   5.1
 10750  12.1  53.8  340  14  7   8.2   4.5 |  12.1  53.8  345  12  6   9.3   5.1
 10500  12.7  54.9  340  14  7   8.6   4.7 |  12.9  55.2  345  11  6  10.0   5.5
 10250  13.4  56.1  340  13  7   9.2   5.0 |  13.6  56.5  345  11  6  10.9   6.0
 10000  14.0  57.2  340  13  7   8.8   4.8 |  14.4  57.9  345  11  6   9.8   5.4
  9750  14.7  58.5  340  13  7   8.5   4.7 |  15.1  59.2  345  11  6   8.9   4.9
  9500  15.3  59.5  345  13  7   8.4   4.6 |  15.8  60.4  350  11  6   9.7   5.3
  9250  15.9  60.6  340  13  7   8.1   4.5 |  16.6  61.9  350  11  6  10.2   5.6
  9000  16.5  61.7  340  13  7   8.5   4.7 |  17.3  63.1  350  11  6  10.1   5.5
  8750  17.1  62.8  335  13  7   9.4   5.2 |  18.1  64.6  350  11  6  10.2   5.6
  8500  17.7  63.9  330  13  7   5.9   3.2 |  18.8  65.8  350  11  6  10.7   5.9
  8250  18.0  64.4  325  12  6   2.8   1.5 |  19.7  67.5  350  11  5  11.0   6.1
  8000  18.2  64.8  320  12  6   4.1   2.3 |  20.5  68.9  350  10  5  11.0   6.0
  7750  18.4  65.1  310  11  6   2.1   1.1 |  21.3  70.3  350  10  5  11.0   6.0
  7500  18.3  64.9  305  11  6  -0.7  -0.4 |  22.1  71.8  350  10  5  11.0   6.1
  7250  18.2  64.8  300   9  5  -0.8  -0.4 |  22.9  73.2  350  10  5  11.2   6.1
  7000  18.0  64.4  290   8  4  -0.7  -0.4 |  23.7  74.7  350   9  5  11.1   6.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/16/2014 at 1500 MDT          |       09/16/2014 at 1800 MDT
                                           |
K index... +21.9  LI... -0.5               | K index... +26.3  LI... -1.0
CAPE... +28.6  CIN... -36.5                | CAPE... +32.7  CIN... -34.3
                                           |
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 -66.2 -87.2  295  54 28   2.2   1.2 | -66.8 -88.2  295  59 30   1.8   1.0
 45000 -62.1 -79.8  295  69 36   4.4   2.4 | -62.2 -80.0  295  75 38   6.3   3.5
 40000 -54.6 -66.3  285  60 31   7.1   3.9 | -52.4 -62.3  290  69 36   5.4   3.0
 38000 -50.4 -58.7  290  52 27   7.1   3.9 | -49.2 -56.6  290  57 29   5.4   3.0
 36000 -46.1 -51.0  300  46 23   7.0   3.8 | -46.0 -50.8  290  44 23   5.1   2.8
 34000 -41.1 -42.0  305  41 21   8.4   4.6 | -41.0 -41.8  295  39 20   8.8   4.8
 32000 -36.1 -33.0  305  37 19   8.4   4.6 | -35.7 -32.3  300  35 18   8.8   4.8
 30000 -31.4 -24.5  300  33 17   7.8   4.3 | -30.9 -23.6  300  34 17   7.9   4.3
 29000 -29.1 -20.4  300  30 16   7.8   4.3 | -28.5 -19.3  300  33 17   7.9   4.3
 28000 -26.7 -16.1  295  28 14   7.8   4.3 | -26.2 -15.2  300  33 17   7.6   4.2
 27000 -23.8 -10.8  295  27 14   7.7   4.2 | -23.5 -10.3  305  31 16   7.2   4.0
 26000 -21.5  -6.7  300  26 14   7.7   4.2 | -21.3  -6.3  305  29 15   7.2   4.0
 25000 -19.2  -2.6  300  26 13   6.7   3.7 | -19.2  -2.6  310  28 14   6.7   3.7
 24000 -17.8  -0.0  300  25 13   4.7   2.6 | -17.5   0.5  310  26 13   5.6   3.1
 23000 -16.4   2.5  295  24 12   4.8   2.6 | -15.8   3.6  310  24 12   5.7   3.1
 22000 -15.0   5.0  295  23 12   5.9   3.2 | -14.2   6.4  310  21 11   5.9   3.3
 21000 -13.0   8.6  295  22 12   7.1   3.9 | -12.4   9.7  305  21 11   6.2   3.4
 20000 -10.9  12.4  295  22 11   7.2   3.9 | -10.6  12.9  300  21 11   6.3   3.4
 19500  -9.9  14.2  295  21 11   7.2   4.0 |  -9.7  14.5  300  21 11   6.2   3.4
 19000  -8.7  16.3  295  21 11   8.9   4.9 |  -8.6  16.5  300  20 10   9.2   5.0
 18500  -7.5  18.5  300  21 11   8.8   4.8 |  -7.4  18.7  300  19 10   8.9   4.9
 18000  -6.2  20.8  300  21 11   8.6   4.7 |  -6.1  21.0  300  17  9   8.6   4.7
 17500  -5.0  23.0  305  20 11   8.5   4.7 |  -4.9  23.2  300  15  8   8.3   4.6
 17000  -3.7  25.3  305  20 10   8.5   4.7 |  -3.7  25.3  300  13  7   8.4   4.6
 16500  -2.5  27.5  310  19 10   8.0   4.4 |  -2.6  27.3  305  11  5   7.1   3.9
 16000  -1.4  29.5  315  17  9   8.1   4.4 |  -1.6  29.1  310   8  4   7.2   4.0
 15500  -0.2  31.6  320  16  8   7.7   4.2 |  -0.5  31.1  325   6  3   7.5   4.1
 15000   0.9  33.6  330  15  8   7.7   4.2 |   0.6  33.1  345   5  3   7.6   4.2
 14500   2.0  35.6  335  14  7   8.0   4.4 |   1.8  35.2  010   5  3   8.1   4.5
 14000   3.9  39.0  345  12  6   8.3   4.6 |   3.7  38.7  035   6  3   8.9   4.9
 13500   5.2  41.4  355  10  5   9.4   5.1 |   5.1  41.2  045   7  4   9.3   5.1
 13000   6.6  43.9  360  10  5   9.6   5.3 |   6.5  43.7  050   8  4   9.3   5.1
 12500   8.0  46.4  010   9  5   9.5   5.2 |   7.9  46.2  055   8  4   9.7   5.3
 12000   9.4  48.9  010   9  5   9.9   5.4 |   9.3  48.7  055   8  4   9.7   5.3
 11750  10.2  50.4  010   9  5   9.6   5.3 |  10.0  50.0  055   8  4   9.1   5.0
 11500  10.9  51.6  010   9  5  10.8   5.9 |  10.7  51.3  055   8  4  11.1   6.1
 11250  11.7  53.1  010   9  5  10.4   5.7 |  11.6  52.9  055   9  4  10.8   5.9
 11000  12.4  54.3  010   9  5   9.2   5.0 |  12.3  54.1  055   9  4   8.7   4.8
 10750  13.1  55.6  010   9  5   9.3   5.1 |  13.0  55.4  055   9  4   9.1   5.0
 10500  13.8  56.8  010   9  5  10.0   5.5 |  13.7  56.7  055   9  5   9.6   5.3
 10250  14.6  58.3  010   9  5  10.8   5.9 |  14.4  57.9  055   9  5  10.5   5.7
 10000  15.4  59.7  010   9  5   9.7   5.3 |  15.2  59.4  055   9  5   9.6   5.3
  9750  16.1  61.0  010   9  4   9.0   5.0 |  15.8  60.4  055   9  5   9.0   4.9
  9500  16.8  62.2  015   9  4   9.6   5.2 |  16.5  61.7  055   9  5   9.4   5.2
  9250  17.5  63.5  015   9  4   9.8   5.4 |  17.3  63.1  055   9  5   9.7   5.3
  9000  18.2  64.8  015   9  4   9.9   5.4 |  18.0  64.4  055   9  5   9.7   5.3
  8750  19.0  66.2  015   9  4  10.3   5.7 |  18.7  65.7  055   9  5  10.2   5.6
  8500  19.8  67.6  015   9  4  10.5   5.8 |  19.5  67.1  050   9  5  10.0   5.5
  8250  20.5  68.9  015   9  4  10.6   5.8 |  20.2  68.4  050   9  5   9.6   5.3
  8000  21.3  70.3  015   8  4  10.2   5.6 |  20.9  69.6  050   9  4   9.7   5.3
  7750  22.1  71.8  015   8  4  11.5   6.3 |  21.6  70.9  050   9  4   9.6   5.3
  7500  23.0  73.4  015   8  4  11.8   6.5 |  22.2  72.0  050   8  4   7.0   3.8
  7250  23.8  74.8  015   8  4  10.5   5.7 |  22.6  72.7  050   8  4   4.7   2.6
  7000  24.6  76.3  015   8  4  11.6   6.4 |  23.0  73.4  050   7  4   6.4   3.5
  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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