Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 181012
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0412 MDT Thursday, September 18, 2014

This forecast is for Thursday, September 18, 2014:

If the trigger temperature of 72.9 F/22.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1127 ft/min (5.7 m/s)
   Maximum height of thermals.................. 18550 ft MSL (11792 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1000 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................. 14849 ft MSL (8091 ft AGL)
Thermal soaring outlook for Friday 09/19....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14644 ft MSL (7886 ft AGL)
Wave soaring outlook for Friday 09/19.......... Poor

Remarks...

Sunrise/Sunset.................... 06:43:05 / 19:03:55 MDT
Total possible sunshine........... 12 hr 20 min 49 sec (740 min 49 sec)
Altitude of sun at 12:53:01 MDT... 52.73 degrees

Upper air data from numerical model forecast valid on 09/18/2014 at 0600 MDT

Freezing level.................. 15313 ft MSL (8555 ft AGL)
Convective condensation level... 17216 ft MSL (10458 ft AGL)
Lifted condensation level....... 17448 ft MSL (10690 ft AGL)
Lifted index.................... -1.5
K index......................... +13.3

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   290   46   24   2.7   1.5      M     M       M      M    M
 45000  -61.6 -78.9   290   55   28   4.9   2.7      M     M       M      M    M
 40000  -53.9 -65.0   305   49   25   7.7   4.2      M     M       M      M    M
 38000  -49.3 -56.7   315   47   24   7.7   4.2      M     M       M      M    M
 36000  -44.6 -48.3   330   46   24   7.7   4.2      M     M       M      M    M
 34000  -40.1 -40.2   335   43   22   7.5   4.1      M     M       M      M    M
 32000  -35.0 -31.0   335   37   19   7.5   4.1      M     M       M      M    M
 30000  -30.9 -23.6   335   32   16   6.7   3.7   38.9 102.0     9.0      M    M
 29000  -28.9 -20.0   335   29   15   6.7   3.7   37.8 100.0     8.3      M    M
 28000  -26.9 -16.4   340   26   13   7.1   3.9   36.8  98.2     7.6      M    M
 27000  -24.7 -12.5   340   23   12   7.4   4.1   35.8  96.4     6.9      M    M
 26000  -22.4  -8.3   345   20   10   7.4   4.1   34.9  94.8     6.2      M    M
 25000  -20.2  -4.4   350   17    9   7.5   4.1   34.1  93.5     5.7      M    M
 24000  -18.2  -0.8   355   14    7   6.5   3.6   33.0  91.4     4.8      M    M
 23000  -16.3   2.7   005   12    6   6.5   3.6   31.8  89.3     3.8      M    M
 22000  -14.3   6.3   015   11    6   6.6   3.6   30.8  87.4     2.9      M    M
 21000  -12.2  10.0   025   10    5   7.1   3.9   29.7  85.5     2.1      M    M
 20000  -10.1  13.8   035    9    4   7.1   3.9   28.8  83.9     1.3      M    M
 19500   -9.0  15.8   045    8    4   7.1   3.9   28.4  83.1     0.9      M    M
 19000   -8.0  17.6   050    8    4   6.7   3.7   27.9  82.3     0.5      M    M
 18500   -7.0  19.4   050    7    4   6.6   3.6   27.4  81.3     0.0      M    M
 18000   -6.0  21.2   050    6    3   6.7   3.7   26.9  80.4    -0.4   1086  5.5
 17500   -5.0  23.0   050    6    3   6.9   3.8   26.4  79.5    -0.9   1041  5.3
 17000   -4.0  24.8   045    6    3   6.8   3.8   25.9  78.6    -1.4    996  5.1
 16500   -3.0  26.6   040    6    3   7.6   4.2   25.5  77.9    -1.8    950  4.8
 16000   -1.9  28.6   040    4    2   7.7   4.2   25.1  77.2    -2.2    902  4.6
 15500   -0.2  31.6   045    2    1   8.6   4.7   24.7  76.5    -2.7    828  4.2
 15000    1.0  33.8   085    1    1   8.6   4.7   24.5  76.1    -3.0    778  4.0
 14500    2.2  36.0   160    1    1   9.3   5.1   24.4  75.9    -3.2    726  3.7
 14000    3.6  38.5   175    2    1   9.5   5.2   24.3  75.8    -3.4    671  3.4
 13500    5.0  41.0   180    2    1   9.6   5.3   24.3  75.7    -3.5    615  3.1
 13000    6.4  43.5   185    3    1   9.7   5.3   24.3  75.7    -3.5    558  2.8
 12500    7.8  46.0   190    3    2   8.9   4.9   24.3  75.7    -3.6    501  2.5
 12000    9.0  48.2   195    4    2   9.2   5.1   24.1  75.4    -3.8    448  2.3
 11750    9.7  49.5   200    5    2   9.1   5.0   24.0  75.3    -3.9    421  2.1
 11500   10.4  50.7   205    5    3   9.0   4.9   24.0  75.2    -4.0    394  2.0
 11250   11.0  51.8   205    6    3   8.4   4.6   23.9  75.1    -4.1    368  1.9
 11000   11.6  52.9   205    6    3   8.1   4.4   23.8  74.8    -4.3    343  1.7
 10750   12.2  54.0   205    7    3   8.2   4.5   23.7  74.6    -4.4    317  1.6
 10500   12.8  55.0   205    7    4   8.0   4.4   23.5  74.4    -4.5    291  1.5
 10250   13.4  56.1   205    7    4   7.4   4.0   23.4  74.1    -4.7    266  1.4
 10000   13.9  57.0   205    8    4   7.9   4.4   23.2  73.8    -4.9    242  1.2
  9750   14.6  58.3   205    9    4   8.8   4.8   23.1  73.6    -4.9    215  1.1
  9500   15.3  59.5   205    9    5   8.3   4.5   23.0  73.4    -5.0    188  1.0
  9250   15.9  60.6   205    9    5   7.8   4.3   22.9  73.2    -5.1    162  0.8
  9000   16.5  61.7   205    9    5   7.6   4.2   22.7  72.9    -5.3    137  0.7
  8750   17.1  62.8   200    9    5   9.0   5.0   22.6  72.7    -5.4    111  0.6
  8500   17.7  63.9   200    8    4   6.9   3.8   22.5  72.6    -5.5     84  0.4
  8250   18.1  64.6   200    7    4   4.0   2.2   22.2  71.9    -5.9     67  0.3
  8000   18.3  64.9   200    6    3   2.1   1.1   21.7  71.0    -6.4     52  0.3
  7750   18.6  65.5   205    5    3   9.4   5.1   21.2  70.2    -6.9     37  0.2
  7500   19.0  66.2   215    5    2  -8.8  -4.8   21.0  69.8    -7.2     17  0.1
  7250   17.0  62.6   240    4    2 -34.2 -18.8   18.7  65.6    -9.6     70  0.4
  7000   14.9  58.8   265    5    3 -14.4  -7.9   16.3  61.4   -11.9    123  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/18/2014 at 0900 MDT          |       09/18/2014 at 1200 MDT
                                           |
K index... +6.7  LI... +1.5                | K index... +2.4  LI... +1.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -67.0 -88.6  290  43 22   2.1   1.2 | -67.2 -89.0  290  40 20   2.2   1.2
 45000 -62.4 -80.3  290  53 27   5.4   3.0 | -62.6 -80.7  290  48 25   5.3   2.9
 40000 -54.0 -65.2  305  43 22   7.4   4.1 | -54.2 -65.6  295  37 19   7.5   4.1
 38000 -49.5 -57.1  315  40 20   7.5   4.1 | -49.7 -57.5  300  33 17   7.5   4.1
 36000 -45.0 -49.0  325  38 19   7.5   4.1 | -45.1 -49.2  305  31 16   7.5   4.1
 34000 -40.4 -40.7  330  35 18   7.8   4.3 | -39.8 -39.6  315  26 13   8.0   4.4
 32000 -35.1 -31.2  340  32 17   7.8   4.3 | -35.0 -31.0  330  23 12   7.9   4.3
 30000 -30.5 -22.9  345  28 14   7.6   4.2 | -30.1 -22.2  340  19 10   8.0   4.4
 29000 -28.2 -18.8  345  25 13   7.6   4.2 | -27.7 -17.9  350  17  9   8.0   4.4
 28000 -25.9 -14.6  350  23 12   7.3   4.0 | -25.3 -13.5  355  15  8   7.4   4.1
 27000 -23.8 -10.8  350  20 10   7.1   3.9 | -23.2  -9.8  355  14  7   7.2   4.0
 26000 -21.7  -7.1  350  17  9   7.1   3.9 | -21.0  -5.8  360  12  6   7.2   4.0
 25000 -19.6  -3.3  350  15  8   7.1   3.9 | -18.8  -1.8  360  11  5   7.2   3.9
 24000 -17.6   0.3  355  12  6   6.3   3.5 | -16.8   1.8  360   8  4   6.7   3.7
 23000 -15.7   3.7  005   9  5   6.3   3.5 | -14.8   5.4  360   6  3   6.7   3.7
 22000 -13.8   7.2  015   7  4   6.4   3.5 | -12.8   9.0  360   4  2   6.6   3.6
 21000 -11.8  10.8  030   7  3   6.9   3.8 | -10.9  12.4  025   3  2   6.3   3.5
 20000  -9.7  14.5  045   7  3   6.9   3.8 |  -9.1  15.6  060   3  2   6.3   3.5
 19500  -8.7  16.3  050   7  4   6.9   3.8 |  -8.1  17.4  075   4  2   6.3   3.4
 19000  -7.7  18.1  055   7  3   6.7   3.7 |  -7.1  19.2  085   4  2   6.8   3.7
 18500  -6.7  19.9  060   6  3   6.7   3.7 |  -6.1  21.0  085   4  2   6.8   3.8
 18000  -5.7  21.7  070   4  2   6.6   3.6 |  -5.1  22.8  085   4  2   6.7   3.7
 17500  -4.7  23.5  075   4  2   6.5   3.6 |  -4.1  24.6  095   3  2   6.3   3.5
 17000  -3.8  25.2  085   3  2   6.5   3.6 |  -3.2  26.2  110   2  1   6.3   3.5
 16500  -2.7  27.1  095   3  2   7.4   4.1 |  -2.2  28.0  135   2  1   7.0   3.8
 16000  -1.1  30.0  100   3  1   7.4   4.0 |  -0.7  30.7  175   2  1   6.9   3.8
 15500   0.1  32.2  115   2  1   8.2   4.5 |   0.4  32.7  185   3  2   7.9   4.4
 15000   1.2  34.2  145   2  1   8.2   4.5 |   1.6  34.9  185   4  2   7.9   4.3
 14500   2.4  36.3  170   2  1   8.7   4.8 |   2.7  36.9  190   4  2   8.1   4.4
 14000   3.7  38.7  175   3  1   8.9   4.9 |   3.9  39.0  190   5  3   8.1   4.5
 13500   5.0  41.0  180   3  2   9.0   4.9 |   5.1  41.2  195   6  3   8.6   4.7
 13000   6.3  43.3  185   4  2   8.9   4.9 |   6.4  43.5  200   7  3   8.8   4.9
 12500   7.6  45.7  190   4  2   8.3   4.6 |   7.7  45.9  200   8  4   8.4   4.6
 12000   8.8  47.8  190   5  3   9.3   5.1 |   8.9  48.0  200   8  4   9.0   4.9
 11750   9.5  49.1  190   5  3   9.1   5.0 |   9.5  49.1  200   9  5   8.9   4.9
 11500  10.1  50.2  190   6  3   9.0   4.9 |  10.2  50.4  200  10  5   8.5   4.6
 11250  10.8  51.4  195   6  3   8.6   4.7 |  10.8  51.4  200  10  5   8.7   4.8
 11000  11.4  52.5  195   7  3   8.6   4.7 |  11.5  52.7  200  11  5   9.4   5.2
 10750  12.0  53.6  195   7  4   8.7   4.8 |  12.1  53.8  200  11  6   9.5   5.2
 10500  12.7  54.9  195   8  4   8.5   4.7 |  12.8  55.0  200  12  6   8.9   4.9
 10250  13.2  55.8  200   8  4   7.9   4.3 |  13.4  56.1  200  12  6   7.0   3.9
 10000  13.8  56.8  200   9  5   8.4   4.6 |  13.9  57.0  200  12  6   8.8   4.8
  9750  14.5  58.1  200   9  5   9.3   5.1 |  14.7  58.5  195  12  6  10.9   6.0
  9500  15.1  59.2  200  10  5   8.3   4.6 |  15.4  59.7  195  12  6   9.9   5.5
  9250  15.7  60.3  200  11  5   6.9   3.8 |  16.1  61.0  195  12  6   9.2   5.0
  9000  16.2  61.2  200  11  6   6.9   3.8 |  16.8  62.2  195  12  6   9.4   5.2
  8750  16.7  62.1  200  11  6   9.1   5.0 |  17.5  63.5  195  12  6  10.9   6.0
  8500  17.4  63.3  200  11  6   8.0   4.4 |  18.4  65.1  190  12  6  11.1   6.1
  8250  17.9  64.2  200  10  5   5.5   3.0 |  19.1  66.4  190  12  6  10.3   5.7
  8000  18.3  64.9  205   9  5   5.3   2.9 |  19.9  67.8  190  12  6  10.3   5.6
  7750  18.7  65.7  205   9  4   6.7   3.7 |  20.7  69.3  190  12  6  10.8   5.9
  7500  19.1  66.4  210   8  4   5.3   2.9 |  21.5  70.7  190  12  6  12.0   6.6
  7250  19.3  66.7  210   6  3   2.4   1.3 |  22.4  72.3  190  12  6  12.4   6.8
  7000  19.4  66.9  220   4  2   4.9   2.7 |  23.3  73.9  190  11  6  12.2   6.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/18/2014 at 1500 MDT          |       09/18/2014 at 1800 MDT
                                           |
K index... +0.6  LI... +3.5                | K index... -1.9  LI... +3.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.1
                                           |
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 -67.5 -89.5  285  38 19   2.6   1.4 | -67.5 -89.5  280  37 19   2.7   1.5
 45000 -62.4 -80.3  285  44 22   5.2   2.9 | -62.3 -80.1  280  43 22   5.3   2.9
 40000 -54.2 -65.6  280  35 18   7.3   4.0 | -53.6 -64.5  275  36 18   7.1   3.9
 38000 -49.8 -57.6  290  32 16   7.4   4.1 | -49.4 -56.9  275  31 16   7.1   3.9
 36000 -45.3 -49.5  295  29 15   7.3   4.0 | -45.1 -49.2  280  27 14   7.1   3.9
 34000 -39.8 -39.6  305  24 13   8.4   4.6 | -40.0 -40.0  290  20 11   8.7   4.8
 32000 -34.7 -30.5  320  21 11   8.7   4.7 | -34.8 -30.6  305  15  8   8.7   4.7
 30000 -29.7 -21.5  320  15  8   8.3   4.6 | -29.7 -21.5  305  12  6   8.5   4.7
 29000 -27.2 -17.0  325  12  6   8.3   4.6 | -27.2 -17.0  300  11  6   8.5   4.7
 28000 -24.7 -12.5  325   9  5   7.6   4.2 | -24.6 -12.3  295  10  5   8.1   4.4
 27000 -22.5  -8.5  325   7  4   7.4   4.1 | -21.8  -7.2  280   7  4   7.4   4.1
 26000 -20.3  -4.5  330   5  3   7.4   4.1 | -19.6  -3.3  265   6  3   7.4   4.1
 25000 -18.1  -0.6  340   3  2   7.3   4.0 | -17.4   0.7  240   5  3   7.2   3.9
 24000 -16.0   3.2  340   2  1   6.8   3.7 | -15.4   4.3  235   5  2   6.7   3.6
 23000 -14.0   6.8  330   2  1   6.8   3.8 | -13.4   7.9  230   4  2   6.7   3.7
 22000 -11.9  10.6  305   1  1   6.7   3.7 | -11.4  11.5  220   4  2   6.4   3.5
 21000 -10.1  13.8  220   1  0   5.9   3.3 |  -9.6  14.7  215   4  2   5.9   3.3
 20000  -8.3  17.1  180   2  1   6.0   3.3 |  -7.9  17.8  210   4  2   5.9   3.3
 19500  -7.4  18.7  175   2  1   5.9   3.2 |  -7.0  19.4  205   4  2   5.9   3.2
 19000  -6.5  20.3  170   3  2   6.6   3.6 |  -6.1  21.0  200   4  2   6.4   3.5
 18500  -5.5  22.1  160   3  2   6.6   3.6 |  -5.1  22.8  190   4  2   6.4   3.5
 18000  -4.5  23.9  155   4  2   6.7   3.7 |  -4.2  24.4  180   5  2   6.6   3.6
 17500  -3.5  25.7  155   4  2   6.9   3.8 |  -3.1  26.4  175   4  2   7.0   3.9
 17000  -2.5  27.5  165   3  2   6.9   3.8 |  -2.1  28.2  175   3  2   7.0   3.8
 16500  -1.0  30.2  195   2  1   7.2   4.0 |  -1.1  30.0  180   2  1   7.6   4.2
 16000   0.1  32.2  225   3  1   7.2   4.0 |   0.0  32.0  200   2  1   7.7   4.2
 15500   1.2  34.2  235   4  2   8.1   4.5 |   1.1  34.0  230   1  1   8.2   4.5
 15000   2.4  36.3  235   4  2   8.1   4.4 |   2.4  36.3  215   2  1   8.5   4.7
 14500   3.5  38.3  230   5  3   8.2   4.5 |   3.6  38.5  205   3  1   8.5   4.7
 14000   4.8  40.6  225   6  3   8.3   4.6 |   4.9  40.8  195   4  2   8.1   4.4
 13500   6.0  42.8  220   6  3   8.5   4.6 |   6.7  44.1  185   7  3   7.9   4.4
 13000   7.3  45.1  210   7  4   8.5   4.7 |   7.8  46.0  185   9  5   7.8   4.3
 12500   8.6  47.5  205   9  4   7.1   3.9 |   9.0  48.2  185  11  6   6.8   3.7
 12000   9.6  49.3  200  10  5   8.4   4.6 |  10.0  50.0  185  13  7   7.8   4.3
 11750  10.2  50.4  200  11  6   8.1   4.4 |  10.5  50.9  185  14  7   7.0   3.9
 11500  10.8  51.4  195  12  6   7.9   4.3 |  11.1  52.0  185  15  8   8.9   4.9
 11250  11.4  52.5  195  13  7   8.2   4.5 |  11.8  53.2  185  15  8   8.7   4.8
 11000  12.0  53.6  195  14  7   8.8   4.8 |  12.3  54.1  180  16  8   6.8   3.7
 10750  12.6  54.7  190  15  8   8.7   4.8 |  12.8  55.0  180  17  9   7.3   4.0
 10500  13.3  55.9  190  16  8   8.6   4.7 |  13.3  55.9  180  18  9   7.4   4.0
 10250  13.9  57.0  190  16  8   8.0   4.4 |  13.8  56.8  180  19 10   7.9   4.3
 10000  14.5  58.1  185  17  9   9.5   5.2 |  14.4  57.9  180  19 10   8.7   4.8
  9750  15.3  59.5  185  17  9  10.9   6.0 |  15.1  59.2  180  19 10   9.1   5.0
  9500  16.0  60.8  185  17  9  10.2   5.6 |  15.7  60.3  180  20 10   9.0   4.9
  9250  16.8  62.2  185  17  9   9.3   5.1 |  16.4  61.5  180  20 10   8.8   4.8
  9000  17.5  63.5  185  17  9   9.3   5.1 |  17.0  62.6  180  20 10   9.1   5.0
  8750  18.2  64.8  185  17  9  10.9   6.0 |  17.7  63.9  180  20 10  10.4   5.7
  8500  19.0  66.2  185  17  9  11.0   6.0 |  18.5  65.3  180  20 10  10.4   5.7
  8250  19.8  67.6  185  17  9  10.2   5.6 |  19.3  66.7  180  20 10   9.6   5.3
  8000  20.6  69.1  185  17  9   9.9   5.4 |  20.0  68.0  180  19 10   9.4   5.2
  7750  21.3  70.3  185  17  9  11.1   6.1 |  20.7  69.3  180  19 10   9.8   5.4
  7500  22.2  72.0  185  16  8  12.2   6.7 |  21.3  70.3  180  18  9   7.2   4.0
  7250  23.1  73.6  180  16  8  11.6   6.4 |  21.7  71.1  180  16  8   4.1   2.3
  7000  23.9  75.0  180  15  8  12.1   6.7 |  22.0  71.6  175  14  7   5.6   3.1
  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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