Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251242
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0642 MDT Saturday, October 25, 2014

This forecast is for Saturday, October 25, 2014:

If the trigger temperature of 72.1 F/22.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 648 ft/min (3.3 m/s)
   Maximum height of thermals.................. 13741 ft MSL (6983 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1330 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................. 8379 ft MSL (1621 ft AGL)
Thermal soaring outlook for Sunday 10/26....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Poor
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18544 ft MSL (11786 ft AGL)
Wave soaring outlook for Sunday 10/26.......... Fair

Remarks...

Sunrise/Sunset.................... 07:18:55 / 18:08:08 MDT
Total possible sunshine........... 10 hr 49 min 14 sec (649 min 14 sec)
Altitude of sun at 12:43:08 MDT... 38.81 degrees

Upper air data from numerical model forecast valid on 10/25/2014 at 0600 MDT

Freezing level.................. 15654 ft MSL (8896 ft AGL)
Convective condensation level... 24269 ft MSL (17511 ft AGL)
Lifted condensation level....... 20229 ft MSL (13471 ft AGL)
Lifted index.................... +6.3
K index......................... -4.4

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  -70.4 -94.7   275   34   18   3.5   1.9      M     M       M      M    M
 45000  -64.5 -84.1   265   34   18   5.4   3.0      M     M       M      M    M
 40000  -55.7 -68.3   255   37   19   7.2   3.9      M     M       M      M    M
 38000  -51.3 -60.3   255   36   18   7.2   4.0      M     M       M      M    M
 36000  -47.0 -52.6   260   35   18   7.1   3.9      M     M       M      M    M
 34000  -42.4 -44.3   260   34   17   7.8   4.3      M     M       M      M    M
 32000  -37.7 -35.9   255   32   16   7.7   4.2      M     M       M      M    M
 30000  -32.8 -27.0   255   29   15   8.4   4.6   37.1  98.8    10.7      M    M
 29000  -30.3 -22.5   255   28   14   8.4   4.6   36.7  98.0    10.4      M    M
 28000  -27.7 -17.9   255   26   14   8.3   4.5   36.3  97.4    10.3      M    M
 27000  -24.7 -12.5   265   22   11   8.0   4.4   35.4  95.6     9.7      M    M
 26000  -22.3  -8.1   270   18    9   8.0   4.4   34.7  94.5     9.3      M    M
 25000  -19.9  -3.8   280   15    8   7.9   4.3   34.2  93.6     9.0      M    M
 24000  -17.6   0.3   280   15    8   7.7   4.2   33.4  92.1     8.4      M    M
 23000  -15.3   4.5   280   14    7   7.7   4.2   32.7  90.8     7.8      M    M
 22000  -13.0   8.6   275   14    7   7.6   4.2   32.0  89.7     7.4      M    M
 21000  -10.7  12.7   270   15    8   7.5   4.1   31.2  88.1     6.7      M    M
 20000   -8.5  16.7   270   15    8   7.5   4.1   30.4  86.8     6.2      M    M
 19500   -7.4  18.7   265   16    8   7.5   4.1   30.1  86.2     5.9      M    M
 19000   -6.4  20.5   265   16    8   5.9   3.2   29.6  85.2     5.5      M    M
 18500   -5.5  22.1   260   17    9   6.0   3.3   28.9  84.1     4.9      M    M
 18000   -4.6  23.7   260   17    9   6.4   3.5   28.3  83.0     4.4      M    M
 17500   -3.6  25.5   260   17    9   6.7   3.7   27.8  82.1     4.0      M    M
 17000   -2.6  27.3   260   17    9   6.7   3.7   27.3  81.2     3.5      M    M
 16500   -1.7  28.9   255   17    9   6.2   3.4   26.8  80.2     3.0      M    M
 16000   -0.8  30.6   255   17    9   6.4   3.5   26.2  79.2     2.5      M    M
 15500    0.1  32.2   250   17    9   5.6   3.1   25.6  78.1     1.9      M    M
 15000    0.8  33.4   245   17    9   5.7   3.1   24.9  76.9     1.1      M    M
 14500    1.5  34.7   240   17    9   7.0   3.8   24.3  75.7     0.4      M    M
 14000    3.4  38.1   235   15    8   8.4   4.6   23.9  75.1     0.1      M    M
 13500    4.7  40.5   230   14    7   8.6   4.7   23.7  74.7    -0.1    610  3.1
 13000    5.9  42.6   235   12    6   8.7   4.8   23.6  74.4    -0.3    557  2.8
 12500    7.2  45.0   240   11    5   8.0   4.4   23.4  74.0    -0.5    505  2.6
 12000    8.5  47.3   250   10    5   9.1   5.0   23.2  73.7    -0.7    451  2.3
 11750    9.2  48.6   250   10    5   9.0   4.9   23.1  73.6    -0.7    423  2.1
 11500    9.8  49.6   255   10    5   9.1   5.0   23.1  73.5    -0.8    395  2.0
 11250   10.5  50.9   260    9    5   8.5   4.7   23.0  73.4    -0.8    367  1.9
 11000   11.2  52.2   265    9    5   7.8   4.3   22.9  73.2    -0.9    341  1.7
 10750   11.8  53.2   265    9    4   7.8   4.3   22.7  72.9    -1.0    315  1.6
 10500   12.4  54.3   270    8    4   7.9   4.3   22.6  72.7    -1.1    289  1.5
 10250   13.0  55.4   270    8    4   8.0   4.4   22.4  72.4    -1.3    264  1.3
 10000   13.6  56.5   270    8    4   7.7   4.2   22.3  72.2    -1.4    238  1.2
  9750   14.2  57.6   275    7    4   7.6   4.2   22.1  71.9    -1.5    213  1.1
  9500   14.8  58.6   275    7    4   7.0   3.8   22.0  71.5    -1.7    188  1.0
  9250   15.3  59.5   275    6    3   6.3   3.5   21.7  71.1    -1.9    167  0.8
  9000   15.7  60.3   275    6    3   6.6   3.6   21.5  70.6    -2.2    145  0.7
  8750   16.2  61.2   275    6    3   6.6   3.6   21.2  70.2    -2.4    123  0.6
  8500   16.7  62.1   280    6    3   3.8   2.1   20.9  69.7    -2.7    102  0.5
  8250   16.7  62.1   280    6    3  -0.8  -0.4   20.3  68.5    -3.4     92  0.5
  8000   16.8  62.2   280    6    3   7.4   4.1   19.6  67.4    -4.0     83  0.4
  7750   16.9  62.4   280    6    3 -20.7 -11.3   19.0  66.2    -4.7     73  0.4
  7500   13.9  57.0   280    6    3 -39.6 -21.8   15.5  59.9    -8.3    156  0.8
  7250   11.8  53.2   285    7    4 -21.6 -11.9   13.1  55.5   -10.7    210  1.1
  7000    9.8  49.6   285    8    4 -37.6 -20.6   10.6  51.2   -13.2    265  1.3
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           10/25/2014 at 0900 MDT          |       10/25/2014 at 1200 MDT
                                           |
K index... +0.2  LI... +4.2                | K index... +0.9  LI... +3.3
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 -69.7 -93.5  270  33 17   3.5   1.9 | -69.5 -93.1  255  33 17   4.2   2.3
 45000 -63.9 -83.0  260  35 18   5.2   2.9 | -63.1 -81.6  250  35 18   4.6   2.5
 40000 -55.3 -67.5  250  40 21   7.2   3.9 | -55.4 -67.7  235  46 24   7.6   4.2
 38000 -51.0 -59.8  250  39 20   7.3   4.0 | -50.7 -59.3  230  44 22   7.7   4.2
 36000 -46.6 -51.9  250  37 19   7.2   4.0 | -46.1 -51.0  230  41 21   7.8   4.3
 34000 -42.2 -44.0  245  35 18   7.4   4.1 | -41.7 -43.1  230  39 20   7.2   4.0
 32000 -37.7 -35.9  240  34 18   7.4   4.1 | -37.4 -35.3  230  38 20   7.2   4.0
 30000 -32.8 -27.0  240  31 16   8.4   4.6 | -32.5 -26.5  230  35 18   8.4   4.6
 29000 -30.3 -22.5  240  30 15   8.4   4.6 | -30.0 -22.0  230  34 17   8.4   4.6
 28000 -27.2 -17.0  240  27 14   7.5   4.1 | -26.9 -16.4  230  32 17   7.2   3.9
 27000 -25.0 -13.0  235  23 12   7.5   4.1 | -24.8 -12.6  225  31 16   7.1   3.9
 26000 -22.7  -8.9  230  19 10   7.5   4.1 | -22.6  -8.7  220  30 15   7.1   3.9
 25000 -20.5  -4.9  225  14  7   7.6   4.1 | -20.5  -4.9  215  29 15   7.1   3.9
 24000 -18.2  -0.8  225  15  7   7.6   4.2 | -18.4  -1.1  215  28 15   7.2   4.0
 23000 -15.9   3.4  225  15  8   7.6   4.2 | -16.2   2.8  220  28 14   7.3   4.0
 22000 -13.6   7.5  225  16  8   7.2   4.0 | -14.0   6.8  220  28 14   7.1   3.9
 21000 -11.6  11.1  230  17  9   6.8   3.7 | -12.0  10.4  225  28 14   6.9   3.8
 20000  -9.6  14.7  235  18  9   6.8   3.7 | -10.0  14.0  230  29 15   6.9   3.8
 19500  -8.6  16.5  235  19 10   6.8   3.7 |  -8.9  16.0  235  29 15   6.9   3.8
 19000  -7.6  18.3  240  20 10   6.7   3.7 |  -7.9  17.8  235  28 15   7.6   4.2
 18500  -6.6  20.1  240  20 11   6.8   3.7 |  -6.7  19.9  235  27 14   7.6   4.1
 18000  -5.6  21.9  245  21 11   7.4   4.0 |  -5.6  21.9  235  26 13   7.8   4.3
 17500  -4.4  24.1  245  21 11   7.8   4.3 |  -4.4  24.1  240  25 13   8.1   4.4
 17000  -3.3  26.1  250  21 11   7.9   4.3 |  -3.2  26.2  240  24 12   8.1   4.4
 16500  -2.2  28.0  245  20 10   7.2   4.0 |  -2.0  28.4  240  23 12   7.9   4.3
 16000  -1.1  30.0  245  19 10   7.4   4.1 |  -0.8  30.6  235  22 11   8.0   4.4
 15500  -0.1  31.8  240  18  9   5.9   3.2 |   0.3  32.5  235  21 11   6.3   3.5
 15000   0.6  33.1  240  16  8   5.7   3.1 |   1.1  34.0  235  19 10   5.9   3.2
 14500   1.4  34.5  235  14  7   6.3   3.5 |   1.9  35.4  235  17  9   6.1   3.4
 14000   2.9  37.2  225  11  6   6.9   3.8 |   3.2  37.8  230  14  7   6.6   3.6
 13500   3.9  39.0  215  10  5   8.0   4.4 |   4.2  39.6  230  13  7   7.6   4.2
 13000   5.1  41.2  215   9  4   8.2   4.5 |   5.3  41.5  225  12  6   7.8   4.3
 12500   6.3  43.3  210   7  4   7.7   4.2 |   6.4  43.5  220  10  5   7.5   4.1
 12000   7.6  45.7  205   7  3   8.9   4.9 |   7.6  45.7  215  10  5   8.2   4.5
 11750   8.3  46.9  205   6  3   8.8   4.8 |   8.2  46.8  215  10  5   8.2   4.5
 11500   8.9  48.0  205   6  3   8.7   4.8 |   8.8  47.8  210  10  5   7.9   4.3
 11250   9.6  49.3  205   6  3   8.4   4.6 |   9.4  48.9  210   9  5   7.5   4.1
 11000  10.2  50.4  205   5  3   8.3   4.6 |  10.0  50.0  210   9  5   7.4   4.0
 10750  10.8  51.4  205   5  3   8.3   4.5 |  10.5  50.9  205   9  5   7.4   4.0
 10500  11.5  52.7  200   5  2   8.5   4.6 |  11.1  52.0  205   9  5   7.3   4.0
 10250  12.1  53.8  200   4  2   9.0   5.0 |  11.6  52.9  205   9  5   7.2   4.0
 10000  12.8  55.0  195   4  2   7.8   4.3 |  12.2  54.0  200   9  4   7.2   3.9
  9750  13.3  55.9  190   4  2   6.5   3.6 |  12.7  54.9  200   8  4   7.1   3.9
  9500  13.9  57.0  185   3  2   7.1   3.9 |  13.3  55.9  195   7  4   6.9   3.8
  9250  14.4  57.9  180   3  1   7.2   4.0 |  13.8  56.8  190   6  3   6.5   3.6
  9000  14.9  58.8  175   2  1   7.2   4.0 |  14.3  57.7  185   5  3   7.1   3.9
  8750  15.5  59.9  170   2  1   6.5   3.6 |  14.9  58.8  175   4  2   9.8   5.4
  8500  15.9  60.6  165   2  1   4.6   2.5 |  15.7  60.3  160   4  2  10.3   5.7
  8250  16.2  61.2  170   1  0   2.6   1.5 |  16.4  61.5  160   4  2   9.3   5.1
  8000  16.4  61.5  000   0  0   6.2   3.4 |  17.1  62.8  155   4  2   9.3   5.1
  7750  16.7  62.1  315   1  0  -6.0  -3.3 |  17.8  64.0  150   4  2  10.4   5.7
  7500  15.5  59.9  295   2  1 -17.6  -9.7 |  18.6  65.5  145   4  2  10.4   5.7
  7250  14.4  57.9  295   3  2 -12.7  -7.0 |  19.3  66.7  145   4  2   8.8   4.8
  7000  13.2  55.8  295   4  2 -17.4  -9.5 |  20.0  68.0  145   4  2  10.1   5.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           10/25/2014 at 1500 MDT          |       10/25/2014 at 1800 MDT
                                           |
K index... +4.7  LI... +3.3                | K index... +2.9  LI... +3.0
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -69.5 -93.1  250  42 21   4.1   2.3 | -69.7 -93.5  250  48 25   4.4   2.4
 45000 -63.0 -81.4  240  41 21   4.7   2.6 | -62.6 -80.7  235  46 24   4.8   2.7
 40000 -55.7 -68.3  230  51 26   7.7   4.2 | -55.2 -67.4  230  50 26   6.9   3.8
 38000 -51.2 -60.2  230  50 26   7.5   4.1 | -51.2 -60.2  230  51 26   6.7   3.7
 36000 -46.7 -52.1  225  49 25   7.5   4.1 | -47.2 -53.0  230  52 27   6.7   3.7
 34000 -41.7 -43.1  225  48 25   7.4   4.1 | -42.8 -45.0  230  50 26   7.5   4.1
 32000 -37.2 -35.0  225  47 24   7.4   4.0 | -37.8 -36.0  230  48 25   7.4   4.1
 30000 -32.5 -26.5  225  41 21   7.9   4.3 | -33.1 -27.6  230  44 23   7.9   4.3
 29000 -30.1 -22.2  230  38 20   7.9   4.3 | -30.7 -23.3  230  42 21   7.9   4.3
 28000 -27.7 -17.9  230  35 18   7.9   4.3 | -28.3 -18.9  225  40 20   7.9   4.3
 27000 -25.4 -13.7  230  35 18   7.9   4.3 | -26.0 -14.8  225  39 20   7.9   4.3
 26000 -23.0  -9.4  230  35 18   7.9   4.3 | -23.6 -10.5  225  39 20   7.9   4.3
 25000 -20.6  -5.1  225  35 18   7.9   4.3 | -21.2  -6.2  225  39 20   7.9   4.3
 24000 -18.4  -1.1  225  35 18   7.3   4.0 | -18.9  -2.0  230  38 20   7.8   4.3
 23000 -16.2   2.8  230  37 19   7.3   4.0 | -16.5   2.3  230  37 19   7.8   4.3
 22000 -14.0   6.8  230  38 19   7.3   4.0 | -14.2   6.4  235  36 18   7.7   4.2
 21000 -11.9  10.6  230  37 19   7.1   3.9 | -12.1  10.2  235  35 18   6.7   3.7
 20000  -9.8  14.4  230  36 18   7.1   3.9 | -10.1  13.8  235  34 17   6.7   3.7
 19500  -8.7  16.3  230  35 18   7.1   3.9 |  -9.1  15.6  235  33 17   6.7   3.7
 19000  -7.7  18.1  230  34 18   7.0   3.8 |  -8.1  17.4  235  33 17   6.5   3.6
 18500  -6.6  20.1  230  33 17   7.0   3.8 |  -7.1  19.2  240  33 17   6.5   3.6
 18000  -5.6  21.9  230  32 17   7.0   3.9 |  -6.2  20.8  240  32 17   6.5   3.6
 17500  -4.5  23.9  230  31 16   7.1   3.9 |  -5.2  22.6  240  31 16   6.6   3.6
 17000  -3.5  25.7  230  29 15   7.1   3.9 |  -4.2  24.4  240  30 15   6.6   3.6
 16500  -2.4  27.7  230  28 14   8.0   4.4 |  -3.2  26.2  240  28 15   7.6   4.1
 16000  -0.6  30.9  230  26 13   8.0   4.4 |  -2.1  28.2  245  27 14   7.7   4.2
 15500   0.6  33.1  230  24 12   8.1   4.5 |  -0.3  31.5  245  24 12   9.0   5.0
 15000   1.8  35.2  230  23 12   8.2   4.5 |   1.0  33.8  245  23 12   9.0   4.9
 14500   3.0  37.4  230  22 11   7.3   4.0 |   2.3  36.1  250  21 11   9.0   4.9
 14000   4.0  39.2  230  20 10   7.3   4.0 |   3.6  38.5  250  20 10   9.1   5.0
 13500   5.0  41.0  230  18  9   7.3   4.0 |   4.9  40.8  250  18  9   9.1   5.0
 13000   6.0  42.8  225  16  8   7.3   4.0 |   6.3  43.3  245  18  9   9.2   5.0
 12500   7.0  44.6  225  14  7   7.4   4.1 |   7.6  45.7  245  17  9   8.7   4.8
 12000   8.1  46.6  220  12  6   7.9   4.3 |   8.8  47.8  240  16  8   8.6   4.7
 11750   8.7  47.7  215  12  6   7.7   4.2 |   9.5  49.1  240  16  8   8.8   4.8
 11500   9.3  48.7  215  11  6   8.3   4.5 |  10.1  50.2  235  16  8   7.6   4.2
 11250   9.9  49.8  210  11  5   7.6   4.2 |  10.6  51.1  235  15  8   6.3   3.4
 11000  10.4  50.7  205  10  5   6.3   3.5 |  11.0  51.8  230  15  8   6.7   3.7
 10750  10.9  51.6  200  10  5   6.2   3.4 |  11.5  52.7  225  15  8   7.0   3.9
 10500  11.4  52.5  195   9  5   6.5   3.5 |  12.0  53.6  225  15  8   6.4   3.5
 10250  11.9  53.4  190   9  5   6.6   3.6 |  12.4  54.3  220  14  7   4.0   2.2
 10000  12.4  54.3  185   9  5   7.4   4.0 |  12.7  54.9  215  14  7   4.9   2.7
  9750  12.9  55.2  180  10  5   8.0   4.4 |  13.2  55.8  210  14  7   6.7   3.7
  9500  13.5  56.3  175  10  5   7.9   4.4 |  13.6  56.5  205  15  8   6.2   3.4
  9250  14.1  57.4  175  10  5   8.1   4.4 |  14.1  57.4  200  15  8   6.3   3.5
  9000  14.7  58.5  175  10  5   8.4   4.6 |  14.6  58.3  195  15  8   6.4   3.5
  8750  15.4  59.7  175  10  5  10.3   5.7 |  15.0  59.0  190  16  8   6.8   3.7
  8500  16.2  61.2  170  10  5  10.9   6.0 |  15.6  60.1  190  16  8   7.1   3.9
  8250  17.0  62.6  170  10  5  10.2   5.6 |  16.1  61.0  185  16  8   7.4   4.1
  8000  17.8  64.0  170  10  5  10.5   5.7 |  16.6  61.9  185  16  8   6.9   3.8
  7750  18.5  65.3  170  10  5   9.9   5.4 |  17.2  63.0  185  16  8   8.9   4.9
  7500  19.2  66.6  170  10  5   9.4   5.2 |  17.7  63.9  180  15  8   0.0   0.0
  7250  19.9  67.8  170  10  5   9.7   5.3 |  17.1  62.8  180  12  6 -10.2  -5.6
  7000  20.6  69.1  170  10  5   9.5   5.2 |  16.5  61.7  175   9  5  -2.2  -1.2
  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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