Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 261037
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0437 MDT Tuesday, August 26, 2014

This forecast is for Tuesday, August 26, 2014:

If the trigger temperature of 71.7 F/22.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 11250 ft MSL (4492 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9389 ft MSL (2631 ft AGL)
Thermal soaring outlook for Wednesday 08/27.... Fair

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 PVA
Potential height of wave....................... 46378 ft MSL (39620 ft AGL)
Wave soaring outlook for Wednesday 08/27....... Poor

Remarks...

Sunrise/Sunset.................... 06:22:29 / 19:39:39 MDT
Total possible sunshine........... 13 hr 17 min 10 sec (797 min 10 sec)
Altitude of sun at 13:00:40 MDT... 61.28 degrees

Upper air data from numerical model forecast valid on 08/26/2014 at 0600 MDT

Freezing level.................. 15668 ft MSL (8910 ft AGL)
Convective condensation level... 13239 ft MSL (6481 ft AGL)
Lifted condensation level....... 12385 ft MSL (5627 ft AGL)
Lifted index.................... -4.5
K index......................... +23.9

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  -64.6 -84.3   240   38   19   0.6   0.3      M     M       M      M    M
 45000  -61.7 -79.1   240   46   24   4.7   2.6      M     M       M      M    M
 40000  -54.1 -65.4   250   49   25   7.6   4.2      M     M       M      M    M
 38000  -49.4 -56.9   245   46   24   7.7   4.2      M     M       M      M    M
 36000  -44.8 -48.6   240   43   22   7.7   4.2      M     M       M      M    M
 34000  -40.0 -40.0   235   41   21   8.1   4.4      M     M       M      M    M
 32000  -35.2 -31.4   235   40   20   7.9   4.3      M     M       M      M    M
 30000  -30.1 -22.2   235   35   18   7.5   4.1   39.9 103.8    13.2      M    M
 29000  -27.8 -18.0   235   33   17   7.5   4.1   39.1 102.4    12.8      M    M
 28000  -25.6 -14.1   235   31   16   6.9   3.8   38.4 101.0    12.3      M    M
 27000  -23.6 -10.5   235   30   16   6.8   3.7   37.1  98.8    11.4      M    M
 26000  -21.6  -6.9   235   29   15   6.8   3.7   36.0  96.9    10.6      M    M
 25000  -19.6  -3.3   230   28   14   6.6   3.6   35.1  95.1    10.0      M    M
 24000  -17.7   0.1   230   27   14   5.9   3.2   33.6  92.5     8.9      M    M
 23000  -16.0   3.2   230   26   14   5.9   3.2   32.3  90.1     7.9      M    M
 22000  -14.2   6.4   230   26   13   6.3   3.4   31.0  87.8     6.9      M    M
 21000  -12.1  10.2   230   25   13   7.0   3.8   29.9  85.9     6.0      M    M
 20000  -10.0  14.0   225   25   13   7.0   3.8   29.0  84.2     5.2      M    M
 19500   -9.0  15.8   225   25   13   6.9   3.8   28.6  83.4     4.9      M    M
 19000   -7.9  17.8   225   25   13   8.0   4.4   28.2  82.8     4.6      M    M
 18500   -6.8  19.8   225   25   13   7.9   4.4   27.9  82.2     4.3      M    M
 18000   -5.6  21.9   220   25   13   7.9   4.3   27.6  81.7     4.0      M    M
 17500   -4.5  23.9   225   24   12   7.9   4.3   27.3  81.1     3.7      M    M
 17000   -3.3  26.1   225   23   12   7.9   4.4   27.0  80.5     3.4      M    M
 16500   -2.2  28.0   225   22   11   8.1   4.5   26.7  80.0     3.1      M    M
 16000   -1.0  30.2   230   21   11   8.2   4.5   26.4  79.5     2.8      M    M
 15500    0.1  32.2   230   19   10   7.9   4.4   26.1  79.1     2.5      M    M
 15000    1.8  35.2   240   18    9   7.8   4.3   25.7  78.2     1.9      M    M
 14500    2.9  37.2   240   17    9   8.4   4.6   25.4  77.7     1.7      M    M
 14000    4.2  39.6   245   16    8   8.4   4.6   25.2  77.3     1.4      M    M
 13500    5.4  41.7   250   15    8   8.7   4.8   25.0  77.0     1.2      M    M
 13000    6.6  43.9   250   14    7   8.8   4.8   24.8  76.7     1.0      M    M
 12500    7.9  46.2   250   14    7   8.0   4.4   24.7  76.4     0.8      M    M
 12000    9.0  48.2   250   13    7   8.6   4.7   24.4  75.9     0.5      M    M
 11750    9.6  49.3   250   13    7   8.6   4.7   24.3  75.7     0.3      M    M
 11500   10.2  50.4   250   13    7   7.8   4.3   24.2  75.6     0.2      M    M
 11250   10.7  51.3   255   12    6   6.3   3.5   24.0  75.2    -0.1    356  1.8
 11000   11.1  52.0   255   11    6   5.8   3.2   23.7  74.6    -0.4    337  1.7
 10750   11.4  52.5   255   11    6   5.8   3.2   23.4  74.1    -0.8    318  1.6
 10500   11.8  53.2   255   10    5   5.6   3.1   23.1  73.5    -1.1    300  1.5
 10250   12.2  54.0   255    9    5   5.7   3.1   22.7  72.9    -1.5    281  1.4
 10000   12.5  54.5   255    8    4   4.9   2.7   22.4  72.4    -1.9    263  1.3
  9750   12.8  55.0   260    7    4   5.4   2.9   22.0  71.6    -2.3    246  1.2
  9500   13.1  55.6   265    6    3   1.5   0.8   21.6  70.9    -2.7    229  1.2
  9250   13.0  55.4   260    5    3  -3.2  -1.8   20.7  69.3    -3.6    228  1.2
  9000   12.7  54.9   255    5    3  -2.5  -1.4   19.8  67.6    -4.6    229  1.2
  8750   12.5  54.5   245    5    3  -1.1  -0.6   18.9  66.0    -5.6    227  1.2
  8500   12.4  54.3   235    5    3   0.6   0.3   18.1  64.7    -6.4    222  1.1
  8250   12.4  54.3   225    4    2   0.5   0.3   17.4  63.4    -7.1    214  1.1
  8000   12.5  54.5   210    3    2   1.3   0.7   16.8  62.2    -7.8    206  1.0
  7750   12.5  54.5   180    2    1  -1.9  -1.1   16.1  60.9    -8.6    198  1.0
  7500   12.3  54.1   155    3    1  -0.8  -0.4   15.3  59.5    -9.3    196  1.0
  7250   12.5  54.5   155    2    1   4.4   2.4   15.1  59.2    -9.5    182  0.9
  7000   12.7  54.9   150    2    1   0.2   0.1   14.9  58.9    -9.7    169  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           08/26/2014 at 0900 MDT          |       08/26/2014 at 1200 MDT
                                           |
K index... +24.6  LI... -4.0               | K index... +25.4  LI... -6.1
CAPE... +680.5  CIN... -123.5              | CAPE... +1651.8  CIN... -13.3
                                           |
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 -64.2 -83.6  240  35 18   0.6   0.3 | -63.7 -82.7  235  33 17  -0.0  -0.0
 45000 -61.5 -78.7  235  45 23   4.4   2.4 | -61.4 -78.5  235  47 24   4.8   2.7
 40000 -54.3 -65.7  245  46 24   7.6   4.2 | -53.7 -64.7  235  50 26   7.3   4.0
 38000 -49.6 -57.3  240  43 22   7.7   4.2 | -49.3 -56.7  235  52 27   7.4   4.0
 36000 -45.0 -49.0  235  41 21   7.7   4.2 | -44.9 -48.8  240  53 27   7.3   4.0
 34000 -40.4 -40.7  235  42 21   7.7   4.2 | -40.3 -40.5  235  50 26   7.6   4.2
 32000 -35.8 -32.4  230  44 22   7.5   4.1 | -35.2 -31.4  235  45 23   8.0   4.4
 30000 -30.2 -22.4  230  41 21   8.4   4.6 | -30.3 -22.5  230  42 22   8.2   4.5
 29000 -27.7 -17.9  230  39 20   8.4   4.6 | -27.9 -18.2  230  41 21   8.2   4.5
 28000 -25.4 -13.7  230  37 19   6.1   3.3 | -25.5 -13.9  225  40 20   6.5   3.6
 27000 -23.6 -10.5  230  35 18   6.0   3.3 | -23.6 -10.5  225  37 19   6.4   3.5
 26000 -21.8  -7.2  230  33 17   6.0   3.3 | -21.7  -7.1  225  34 18   6.5   3.5
 25000 -20.0  -4.0  230  31 16   6.1   3.4 | -19.8  -3.6  225  31 16   6.6   3.6
 24000 -18.2  -0.8  230  30 15   6.5   3.5 | -17.8  -0.0  225  28 15   6.8   3.8
 23000 -16.3   2.7  225  28 14   6.5   3.6 | -15.7   3.7  230  25 13   6.8   3.8
 22000 -14.4   6.1  225  26 14   6.7   3.7 | -13.6   7.5  230  22 11   6.7   3.7
 21000 -12.3   9.9  225  24 12   6.9   3.8 | -11.7  10.9  230  20 10   6.5   3.6
 20000 -10.3  13.5  230  22 11   7.0   3.8 |  -9.8  14.4  230  18  9   6.6   3.6
 19500  -9.3  15.3  230  21 11   7.0   3.8 |  -8.9  16.0  230  17  9   6.6   3.6
 19000  -8.3  17.1  230  20 10   7.2   3.9 |  -7.9  17.8  235  16  8   7.0   3.8
 18500  -7.2  19.0  230  20 10   7.2   4.0 |  -6.9  19.6  235  15  8   7.0   3.8
 18000  -6.1  21.0  230  19 10   7.7   4.2 |  -5.9  21.4  240  15  8   7.2   4.0
 17500  -4.9  23.2  235  19 10   8.2   4.5 |  -4.9  23.2  240  14  7   7.4   4.1
 17000  -3.7  25.3  235  18  9   8.2   4.5 |  -3.8  25.2  245  13  7   7.4   4.1
 16500  -2.5  27.5  235  17  9   8.4   4.6 |  -2.6  27.3  250  12  6   7.9   4.3
 16000  -1.3  29.7  240  16  8   8.4   4.6 |  -1.5  29.3  255  12  6   7.9   4.3
 15500  -0.0  32.0  245  15  8   8.4   4.6 |   0.3  32.5  260  11  5   8.0   4.4
 15000   1.8  35.2  250  14  7   8.4   4.6 |   1.5  34.7  265  10  5   8.0   4.4
 14500   3.0  37.4  250  13  7   7.9   4.3 |   2.7  36.9  270   9  5   8.3   4.5
 14000   4.2  39.6  255  12  6   7.9   4.3 |   3.8  38.8  275   9  4   8.3   4.5
 13500   5.3  41.5  255  11  6   8.2   4.5 |   5.1  41.2  280   8  4   8.7   4.8
 13000   6.5  43.7  255  10  5   8.3   4.6 |   6.3  43.3  280   7  4   8.9   4.9
 12500   7.7  45.9  255   9  5   8.7   4.8 |   7.5  45.5  285   6  3   8.9   4.9
 12000   9.0  48.2  255   9  4   9.3   5.1 |   8.9  48.0  285   6  3   9.7   5.3
 11750   9.7  49.5  260   9  4   9.4   5.2 |   9.7  49.5  285   6  3   9.8   5.4
 11500  10.4  50.7  260   9  4   8.8   4.8 |  10.4  50.7  285   5  3   9.2   5.0
 11250  10.9  51.6  255   8  4   8.1   4.4 |  11.0  51.8  285   5  3   8.5   4.7
 11000  11.5  52.7  255   8  4   8.0   4.4 |  11.6  52.9  285   5  3   8.7   4.7
 10750  12.1  53.8  255   8  4   8.1   4.5 |  12.2  54.0  285   5  3   8.6   4.7
 10500  12.6  54.7  255   8  4   7.6   4.2 |  12.9  55.2  280   5  2   8.7   4.8
 10250  13.1  55.6  255   7  4   7.4   4.0 |  13.5  56.3  280   4  2   8.9   4.9
 10000  13.6  56.5  255   7  4   6.6   3.6 |  14.1  57.4  280   4  2   8.1   4.5
  9750  14.0  57.2  255   6  3   6.1   3.4 |  14.5  58.1  275   3  2   7.6   4.2
  9500  14.4  57.9  255   6  3   4.5   2.5 |  15.0  59.0  270   3  1   7.2   4.0
  9250  14.6  58.3  255   6  3   2.8   1.5 |  15.4  59.7  255   2  1   6.3   3.5
  9000  14.8  58.6  260   6  3   3.4   1.9 |  15.8  60.4  240   2  1   7.5   4.1
  8750  15.0  59.0  260   6  3   3.9   2.1 |  16.5  61.7  220   2  1  11.3   6.2
  8500  15.1  59.2  255   6  3   0.4   0.2 |  17.4  63.3  200   2  1  10.6   5.8
  8250  14.9  58.8  245   6  3  -2.0  -1.1 |  17.9  64.2  190   2  1   8.5   4.7
  8000  14.7  58.5  235   6  3  -3.0  -1.6 |  18.5  65.3  180   3  1   8.5   4.7
  7750  14.5  58.1  220   6  3   3.5   1.9 |  19.1  66.4  175   3  2  11.0   6.0
  7500  15.0  59.0  210   5  3   9.4   5.2 |  20.0  68.0  170   3  2  12.8   7.0
  7250  15.5  59.9  205   5  3   6.2   3.4 |  20.9  69.6  170   3  2  11.1   6.1
  7000  16.1  61.0  200   5  3   9.2   5.1 |  21.7  71.1  165   3  2  12.6   6.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           08/26/2014 at 1500 MDT          |       08/26/2014 at 1800 MDT
                                           |
K index... +29.1  LI... -4.6               | K index... +24.9  LI... -2.2
CAPE... +1014.4  CIN... -1.8               | CAPE... +279.5  CIN... -15.8
                                           |
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 -63.7 -82.7  235  37 19   0.2   0.1 | -64.3 -83.7  240  36 19  -0.2  -0.1
 45000 -61.5 -78.7  235  53 27   4.2   2.3 | -62.2 -80.0  240  54 28   4.9   2.7
 40000 -54.5 -66.1  235  60 31   7.9   4.3 | -54.3 -65.7  240  58 30   7.9   4.3
 38000 -49.7 -57.5  230  54 28   8.0   4.4 | -49.5 -57.1  235  56 29   8.0   4.4
 36000 -44.9 -48.8  220  49 25   7.9   4.3 | -44.7 -48.5  235  54 28   7.9   4.4
 34000 -39.6 -39.3  220  45 23   9.0   4.9 | -39.3 -38.7  235  48 25   9.1   5.0
 32000 -33.5 -28.3  215  41 21   9.6   5.3 | -33.2 -27.8  235  41 21   9.5   5.2
 30000 -28.9 -20.0  215  33 17   7.6   4.2 | -28.3 -18.9  230  36 18   8.2   4.5
 29000 -26.6 -15.9  220  29 15   7.6   4.2 | -25.9 -14.6  230  33 17   8.2   4.5
 28000 -24.4 -11.9  220  25 13   6.8   3.8 | -23.5 -10.3  230  31 16   6.9   3.8
 27000 -22.4  -8.3  220  22 12   6.8   3.7 | -21.5  -6.7  230  29 15   7.0   3.8
 26000 -20.4  -4.7  220  20 10   6.8   3.7 | -19.4  -2.9  235  27 14   7.0   3.8
 25000 -18.3  -0.9  220  18  9   6.8   3.7 | -17.4   0.7  235  25 13   6.8   3.8
 24000 -16.4   2.5  220  15  8   6.5   3.6 | -15.5   4.1  230  23 12   6.5   3.6
 23000 -14.5   5.9  225  13  7   6.6   3.6 | -13.6   7.5  225  20 11   6.5   3.6
 22000 -12.6   9.3  225  11  5   6.2   3.4 | -11.7  10.9  215  19 10   6.2   3.4
 21000 -10.9  12.4  225   8  4   5.6   3.1 | -10.0  14.0  210  17  9   5.6   3.0
 20000  -9.3  15.3  225   6  3   5.7   3.1 |  -8.4  16.9  195  15  8   5.6   3.1
 19500  -8.5  16.7  225   4  2   5.7   3.1 |  -7.6  18.3  190  15  8   5.7   3.1
 19000  -7.7  18.1  215   3  2   5.6   3.1 |  -6.9  19.6  185  14  7   4.9   2.7
 18500  -6.8  19.8  200   3  1   5.6   3.1 |  -6.1  21.0  180  14  7   5.0   2.7
 18000  -6.0  21.2  180   3  1   5.9   3.3 |  -5.4  22.3  170  13  7   5.2   2.8
 17500  -5.1  22.8  165   3  1   6.3   3.5 |  -4.6  23.7  165  13  7   5.4   3.0
 17000  -4.2  24.4  150   3  2   6.3   3.5 |  -3.8  25.2  160  13  7   5.3   2.9
 16500  -3.2  26.2  145   4  2   6.9   3.8 |  -3.0  26.6  155  13  7   6.5   3.6
 16000  -1.7  28.9  140   5  3   6.9   3.8 |  -2.0  28.4  155  12  6   6.4   3.5
 15500  -0.6  30.9  135   6  3   8.2   4.5 |  -0.5  31.1  155  12  6   7.1   3.9
 15000   0.6  33.1  135   7  3   8.1   4.5 |   0.5  32.9  155  12  6   7.0   3.8
 14500   1.8  35.2  130   7  4   8.2   4.5 |   1.6  34.9  155  12  6   8.2   4.5
 14000   3.0  37.4  130   7  4   8.3   4.5 |   2.8  37.0  160  12  6   8.3   4.5
 13500   4.2  39.6  130   7  4   8.0   4.4 |   4.0  39.2  165  12  6   7.8   4.3
 13000   5.3  41.5  130   7  4   7.9   4.4 |   5.1  41.2  165  12  6   7.6   4.2
 12500   6.4  43.5  135   7  4   8.6   4.7 |   6.2  43.2  175  11  6   7.3   4.0
 12000   7.7  45.9  140   7  4   9.2   5.0 |   7.2  45.0  180  11  6   7.3   4.0
 11750   8.4  47.1  145   8  4   9.2   5.1 |   7.7  45.9  185  11  5   6.9   3.8
 11500   9.0  48.2  150   8  4   9.4   5.1 |   8.2  46.8  185  11  5   8.2   4.5
 11250   9.7  49.5  150   8  4   9.3   5.1 |   8.9  48.0  190  10  5   9.0   5.0
 11000  10.3  50.5  155   9  5   9.1   5.0 |   9.5  49.1  190  10  5   8.2   4.5
 10750  11.0  51.8  155   9  5   9.1   5.0 |  10.1  50.2  190  10  5   8.3   4.6
 10500  11.6  52.9  155   9  5   9.3   5.1 |  10.7  51.3  190  10  5   8.1   4.5
 10250  12.2  54.0  160  10  5   9.4   5.2 |  11.2  52.2  190  10  5   7.7   4.2
 10000  12.9  55.2  160  10  5   9.5   5.2 |  11.8  53.2  190  10  5   8.4   4.6
  9750  13.6  56.5  160  11  6   9.6   5.3 |  12.4  54.3  190  10  5   9.1   5.0
  9500  14.3  57.7  160  11  6   9.5   5.2 |  13.0  55.4  190  10  5   9.0   4.9
  9250  15.0  59.0  160  11  6   9.4   5.2 |  13.6  56.5  190  10  5   9.0   5.0
  9000  15.7  60.3  165  11  6   9.6   5.3 |  14.2  57.6  190  10  5   9.2   5.0
  8750  16.4  61.5  165  11  6  10.1   5.5 |  14.9  58.8  185  10  5   9.9   5.4
  8500  17.2  63.0  165  12  6  10.5   5.8 |  15.7  60.3  185   9  5  10.1   5.6
  8250  18.0  64.4  165  12  6  10.7   5.9 |  16.4  61.5  185   9  5  10.0   5.5
  8000  18.7  65.7  165  12  6  10.5   5.8 |  17.1  62.8  185   9  5  10.0   5.5
  7750  19.5  67.1  165  12  6  11.1   6.1 |  17.9  64.2  185   9  5  10.1   5.5
  7500  20.3  68.5  165  12  6  10.8   5.9 |  18.5  65.3  180   9  4   8.1   4.4
  7250  21.0  69.8  165  11  6   9.9   5.4 |  19.0  66.2  180   8  4   6.1   3.3
  7000  21.8  71.2  165  11  6  10.6   5.8 |  19.5  67.1  180   8  4   7.6   4.2
  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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