Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 211145
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0545 MDT Sunday, September 21, 2014

This forecast is for Sunday, September 21, 2014:

If the trigger temperature of 61.5 F/16.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 116 ft/min (0.6 m/s)
   Maximum height of thermals.................. 10805 ft MSL (3634 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... None
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................. 9162 ft MSL (1991 ft AGL)
Thermal soaring outlook for Monday 09/22....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... 13798 ft MSL (6627 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 17479 ft MSL (10308 ft AGL)
Wave soaring outlook for Monday 09/22.......... Poor

Remarks...

Sunrise/Sunset.................... 06:45:49 / 18:59:06 MDT
Total possible sunshine........... 12 hr 13 min 17 sec (733 min 17 sec)
Altitude of sun at 12:51:58 MDT... 51.57 degrees

Upper air data from numerical model forecast valid on 09/21/2014 at 0600 MDT

Freezing level.................. 14546 ft MSL (7375 ft AGL)
Convective condensation level... 12314 ft MSL (5143 ft AGL)
Lifted condensation level....... 11215 ft MSL (4044 ft AGL)
Lifted index.................... +3.9
K index......................... +25.8

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  -67.2 -89.0   295   37   19   3.6   1.9      M     M       M      M    M
 45000  -60.3 -76.5   290   58   30   6.2   3.4      M     M       M      M    M
 40000  -51.2 -60.2   280   71   36   5.1   2.8      M     M       M      M    M
 38000  -48.1 -54.6   280   62   32   5.1   2.8      M     M       M      M    M
 36000  -44.7 -48.5   275   52   27   6.3   3.4      M     M       M      M    M
 34000  -39.9 -39.8   280   43   22   8.2   4.5      M     M       M      M    M
 32000  -35.0 -31.0   280   35   18   8.8   4.8      M     M       M      M    M
 30000  -30.3 -22.5   275   28   14   7.9   4.4   40.4 104.7    19.2      M    M
 29000  -27.9 -18.2   270   25   13   7.9   4.4   39.7 103.5    18.9      M    M
 28000  -25.6 -14.1   265   22   11   7.6   4.1   39.1 102.5    18.6      M    M
 27000  -23.4 -10.1   265   21   11   7.5   4.1   38.2 100.7    18.0      M    M
 26000  -21.2  -6.2   260   20   10   7.5   4.1   37.3  99.2    17.5      M    M
 25000  -19.0  -2.2   260   19   10   7.5   4.1   36.6  97.9    17.0      M    M
 24000  -16.9   1.6   260   19   10   7.0   3.9   35.6  96.1    16.3      M    M
 23000  -14.3   6.3   260   20   10   7.1   3.9   34.4  93.9    15.5      M    M
 22000  -12.3   9.9   260   20   10   6.5   3.6   33.5  92.3    14.8      M    M
 21000  -10.5  13.1   260   20   11   6.4   3.5   32.2  90.0    13.8      M    M
 20000   -8.6  16.5   260   21   11   6.4   3.5   31.1  88.0    12.9      M    M
 19500   -7.7  18.1   255   21   11   6.3   3.4   30.6  87.0    12.5      M    M
 19000   -6.9  19.6   255   21   11   5.9   3.2   29.9  85.9    12.0      M    M
 18500   -6.0  21.2   255   21   11   5.9   3.2   29.3  84.7    11.4      M    M
 18000   -5.2  22.6   255   21   11   5.9   3.2   28.6  83.5    10.9      M    M
 17500   -4.3  24.3   250   21   11   5.9   3.2   28.0  82.4    10.3      M    M
 17000   -3.5  25.7   245   20   10   5.8   3.2   27.3  81.2     9.8      M    M
 16500   -2.7  27.1   240   19   10   5.6   3.1   26.7  80.0     9.2      M    M
 16000   -1.9  28.6   235   18   10   5.8   3.2   26.0  78.8     8.6      M    M
 15500   -1.2  29.8   230   18    9   4.1   2.3   25.2  77.4     7.9      M    M
 15000   -0.6  30.9   225   17    9   4.2   2.3   24.3  75.7     7.0      M    M
 14500    0.0  32.0   225   16    8   3.1   1.7   23.4  74.1     6.2      M    M
 14000    0.4  32.7   220   16    8   2.8   1.5   22.2  72.0     5.2      M    M
 13500    0.8  33.4   220   15    8   4.3   2.3   21.1  69.9     4.1      M    M
 13000    1.7  35.1   210   15    8   6.1   3.3   20.5  68.9     3.6      M    M
 12500    2.6  36.7   200   15    8   5.7   3.1   19.9  67.9     3.0      M    M
 12000    3.3  37.9   190   13    7   4.9   2.7   19.2  66.5     2.3      M    M
 11750    3.6  38.5   185   13    6   5.2   2.9   18.8  65.9     1.9      M    M
 11500    4.0  39.2   180   12    6   4.6   2.5   18.4  65.2     1.6      M    M
 11250    4.3  39.7   175   12    6   3.6   2.0   18.0  64.4     1.1      M    M
 11000    4.5  40.1   165   12    6   2.9   1.6   17.5  63.5     0.7      M    M
 10750    4.7  40.5   160   12    6   2.0   1.1   16.9  62.5     0.1      M    M
 10500    4.8  40.6   155   12    6   2.3   1.2   16.3  61.4    -0.5    306  1.6
 10250    5.0  41.0   155   13    7   2.9   1.6   15.8  60.4    -1.0    293  1.5
 10000    5.3  41.5   155   14    7   3.3   1.8   15.3  59.5    -1.5    278  1.4
  9750    5.5  41.9   155   15    8   2.4   1.3   14.8  58.6    -2.0    264  1.3
  9500    6.2  43.2   155   16    8   7.3   4.0   13.9  57.1    -2.8    230  1.2
  9250    6.7  44.1   155   16    8   7.7   4.2   13.8  56.8    -3.0    207  1.1
  9000    7.2  45.0   155   16    8   6.0   3.3   13.6  56.4    -3.2    185  0.9
  8750    7.6  45.7   160   16    8   7.1   3.9   13.3  55.9    -3.6    165  0.8
  8500    8.2  46.8   160   14    7   9.6   5.3   13.2  55.8    -3.7    139  0.7
  8250    8.8  47.8   160   12    6   9.3   5.1   13.2  55.7    -3.8    113  0.6
  8000    9.4  48.9   165   10    5   8.1   4.4   13.1  55.6    -3.9     87  0.4
  7750    9.9  49.8   165    8    4   7.8   4.3   12.9  55.3    -4.2     65  0.3
  7500   10.6  51.1   170    5    3  11.8   6.5   12.9  55.3    -4.2     37  0.2
  7250   11.3  52.3   180    3    1   3.4   1.8   12.9  55.3    -4.3      9  0.0
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           09/21/2014 at 0900 MDT          |       09/21/2014 at 1200 MDT
                                           |
K index... +25.3  LI... +2.0               | K index... +24.4  LI... +1.3
CAPE... 0.0  CIN... -3.0                   | CAPE... +11.4  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 -67.2 -89.0  290  33 17   3.6   2.0 | -67.7 -89.9  290  37 19   3.0   1.6
 45000 -60.4 -76.7  290  54 28   5.8   3.2 | -61.4 -78.5  285  55 29   6.1   3.4
 40000 -51.9 -61.4  280  66 34   5.2   2.8 | -52.3 -62.1  280  60 31   5.7   3.1
 38000 -48.8 -55.8  275  53 27   5.1   2.8 | -48.9 -56.0  275  47 24   5.7   3.1
 36000 -45.3 -49.5  260  41 21   6.8   3.7 | -45.5 -49.9  270  35 18   6.1   3.3
 34000 -40.0 -40.0  260  35 18   9.0   4.9 | -40.1 -40.2  265  28 15   9.3   5.1
 32000 -34.6 -30.3  255  29 15   9.6   5.3 | -34.5 -30.1  260  22 12   9.2   5.1
 30000 -29.9 -21.8  260  24 12   7.9   4.3 | -29.7 -21.5  260  17  9   7.9   4.3
 29000 -27.6 -17.7  260  21 11   7.9   4.3 | -26.7 -16.1  255  13  7   7.9   4.3
 28000 -25.3 -13.5  265  19 10   7.1   3.9 | -24.4 -11.9  255  11  6   7.1   3.9
 27000 -23.2  -9.8  265  18  9   7.0   3.8 | -22.3  -8.1  255  11  5   7.2   4.0
 26000 -21.2  -6.2  265  16  8   7.0   3.8 | -20.2  -4.4  260  10  5   7.3   4.0
 25000 -19.1  -2.4  265  15  8   7.0   3.8 | -18.1  -0.6  260  10  5   6.9   3.8
 24000 -17.0   1.4  265  14  7   7.2   3.9 | -16.1   3.0  255  10  5   6.5   3.6
 23000 -14.4   6.1  270  13  7   7.2   4.0 | -14.2   6.4  250  11  6   6.6   3.6
 22000 -12.3   9.9  275  12  6   6.8   3.7 | -12.3   9.9  250  12  6   6.2   3.4
 21000 -10.4  13.3  270  12  6   6.7   3.7 | -10.6  12.9  240  12  6   6.0   3.3
 20000  -8.5  16.7  270  11  6   6.7   3.7 |  -8.8  16.2  235  13  7   6.0   3.3
 19500  -7.5  18.5  270  10  5   6.6   3.6 |  -8.0  17.6  230  13  7   5.9   3.3
 19000  -6.6  20.1  265  10  5   6.2   3.4 |  -7.2  19.0  225  14  7   5.3   2.9
 18500  -5.7  21.7  260   9  5   6.4   3.5 |  -6.4  20.5  220  15  8   5.3   2.9
 18000  -4.9  23.2  255   9  4   4.8   2.7 |  -5.6  21.9  220  16  8   4.9   2.7
 17500  -4.2  24.4  240   8  4   4.7   2.6 |  -4.9  23.2  215  17  9   4.7   2.6
 17000  -3.6  25.5  230   8  4   4.7   2.6 |  -4.3  24.3  210  18  9   4.7   2.6
 16500  -2.9  26.8  220   9  5   4.9   2.7 |  -3.6  25.5  205  18 10   4.5   2.5
 16000  -2.2  28.0  205  10  5   4.9   2.7 |  -3.0  26.6  205  19 10   4.4   2.4
 15500  -1.5  29.3  195  12  6   5.0   2.7 |  -2.3  27.9  200  20 10   5.1   2.8
 15000  -0.8  30.6  190  13  7   5.1   2.8 |  -1.6  29.1  195  21 11   5.1   2.8
 14500  -0.1  31.8  185  14  7   2.9   1.6 |  -0.8  30.6  195  22 11   4.4   2.4
 14000   0.2  32.4  180  16  8   2.4   1.3 |  -0.3  31.5  190  23 12   4.3   2.3
 13500   0.5  32.9  180  17  9   4.6   2.5 |   0.3  32.5  190  24 12   5.4   3.0
 13000   1.6  34.9  180  17  9   6.6   3.6 |   1.3  34.3  190  24 13   6.9   3.8
 12500   2.6  36.7  180  17  9   6.2   3.4 |   2.4  36.3  190  24 13   6.5   3.6
 12000   3.4  38.1  180  17  9   6.7   3.7 |   3.4  38.1  185  24 12   8.1   4.5
 11750   3.9  39.0  180  17  9   7.1   3.9 |   4.0  39.2  185  24 12   9.0   4.9
 11500   4.4  39.9  180  17  9   6.8   3.7 |   4.6  40.3  185  23 12   8.0   4.4
 11250   4.9  40.8  180  17  9   6.4   3.5 |   5.1  41.2  185  23 12   6.8   3.7
 11000   5.4  41.7  180  17  9   6.5   3.5 |   5.6  42.1  185  22 12   6.3   3.4
 10750   5.8  42.4  185  17  9   7.5   4.1 |   6.0  42.8  185  22 11   6.1   3.3
 10500   6.3  43.3  185  17  9   5.4   3.0 |   6.4  43.5  185  21 11   5.4   3.0
 10250   6.6  43.9  185  17  9   2.2   1.2 |   7.1  44.8  185  20 10   4.5   2.5
 10000   6.7  44.1  185  17  9   1.6   0.9 |   7.4  45.3  185  20 10   4.3   2.4
  9750   6.8  44.2  185  17  9   3.0   1.6 |   7.7  45.9  185  19 10   3.7   2.0
  9500   7.2  45.0  185  16  8   1.5   0.8 |   8.0  46.4  185  18  9   3.7   2.0
  9250   7.4  45.3  190  17  9   2.6   1.4 |   8.2  46.8  190  18  9   3.2   1.8
  9000   7.5  45.5  190  17  9  -1.0  -0.5 |   8.5  47.3  190  17  9   5.1   2.8
  8750   7.4  45.3  190  18  9   3.2   1.8 |   8.9  48.0  195  16  8   6.1   3.4
  8500   7.9  46.2  190  17  9   9.8   5.4 |   9.3  48.7  195  15  8   4.9   2.7
  8250   8.5  47.3  190  16  8   8.4   4.6 |   9.6  49.3  200  15  7   5.4   2.9
  8000   9.1  48.4  190  15  8   7.7   4.2 |  10.0  50.0  200  14  7   4.8   2.6
  7750   9.6  49.3  190  14  7   9.5   5.2 |  10.4  50.7  200  13  6   8.8   4.8
  7500  10.5  50.9  190  12  6  16.4   9.0 |  11.3  52.3  200  11  5  16.7   9.2
  7250  11.5  52.7  185  10  5   3.0   1.7 |  12.2  54.0  195   9  5   2.3   1.3
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           09/21/2014 at 1500 MDT          |       09/21/2014 at 1800 MDT
                                           |
K index... +23.9  LI... +1.0               | K index... +25.9  LI... +1.6
CAPE... 0.0  CIN... -6.4                   | CAPE... 0.0  CIN... -0.9
                                           |
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 -67.1 -88.8  285  36 18   2.6   1.4 | -66.8 -88.2  285  34 17   2.7   1.5
 45000 -61.5 -78.7  285  50 26   6.2   3.4 | -61.1 -78.0  280  48 25   6.1   3.3
 40000 -52.3 -62.1  280  61 31   6.1   3.3 | -52.0 -61.6  275  62 32   6.5   3.5
 38000 -48.7 -55.7  280  48 25   6.1   3.3 | -48.1 -54.6  280  51 26   6.5   3.5
 36000 -44.6 -48.3  275  33 17   7.0   3.8 | -43.7 -46.7  285  38 20   6.9   3.8
 34000 -39.5 -39.1  275  29 15   8.6   4.7 | -39.2 -38.6  285  32 16   7.7   4.2
 32000 -34.3 -29.7  270  25 13   9.2   5.1 | -34.6 -30.3  275  26 13   8.1   4.5
 30000 -29.3 -20.7  270  24 12   8.5   4.7 | -29.6 -21.3  270  22 11   8.5   4.6
 29000 -26.8 -16.2  270  24 12   8.6   4.7 | -27.1 -16.8  270  20 11   8.5   4.7
 28000 -24.3 -11.7  275  23 12   7.4   4.1 | -24.6 -12.3  265  19 10   7.4   4.0
 27000 -22.2  -8.0  275  22 11   7.1   3.9 | -22.6  -8.7  265  20 10   7.0   3.8
 26000 -20.1  -4.2  275  20 10   7.1   3.9 | -20.5  -4.9  265  22 11   7.0   3.8
 25000 -18.1  -0.6  275  19 10   7.1   3.9 | -18.4  -1.1  265  23 12   7.0   3.8
 24000 -16.2   2.8  275  18  9   6.2   3.4 | -16.4   2.5  270  23 12   7.2   3.9
 23000 -13.9   7.0  275  17  9   6.2   3.4 | -13.7   7.3  275  23 12   7.2   3.9
 22000 -12.1  10.2  270  17  9   5.9   3.2 | -11.6  11.1  280  23 12   6.8   3.7
 21000 -10.5  13.1  265  16  8   5.8   3.2 |  -9.7  14.5  280  19 10   6.7   3.7
 20000  -8.8  16.2  260  16  8   5.8   3.2 |  -7.8  18.0  280  14  7   6.7   3.7
 19500  -8.0  17.6  260  16  8   5.7   3.1 |  -6.8  19.8  280  12  6   6.5   3.5
 19000  -7.2  19.0  255  16  8   5.4   3.0 |  -6.1  21.0  280  11  6   4.4   2.4
 18500  -6.4  20.5  250  16  8   5.5   3.0 |  -5.4  22.3  275  10  5   4.6   2.5
 18000  -5.6  21.9  245  17  9   5.2   2.8 |  -4.8  23.4  270   9  5   4.8   2.6
 17500  -4.9  23.2  245  17  9   5.1   2.8 |  -4.1  24.6  265   9  5   4.9   2.7
 17000  -4.2  24.4  240  17  9   5.1   2.8 |  -3.4  25.9  265  10  5   5.0   2.7
 16500  -3.4  25.9  235  18  9   5.1   2.8 |  -2.7  27.1  260  10  5   5.3   2.9
 16000  -2.7  27.1  230  19 10   5.1   2.8 |  -1.9  28.6  260  12  6   5.3   2.9
 15500  -1.9  28.6  225  19 10   5.6   3.1 |  -1.1  30.0  255  13  7   5.6   3.0
 15000  -1.1  30.0  225  20 10   5.6   3.1 |  -0.3  31.5  255  14  7   5.6   3.1
 14500  -0.3  31.5  225  21 11   4.7   2.6 |   0.5  32.9  255  15  8   6.3   3.4
 14000   0.3  32.5  225  21 11   4.3   2.4 |   1.5  34.7  250  16  8   6.7   3.7
 13500   0.9  33.6  225  22 11   5.1   2.8 |   2.5  36.5  245  17  9   6.7   3.7
 13000   1.8  35.2  225  21 11   6.3   3.4 |   3.5  38.3  240  18  9   6.7   3.7
 12500   2.7  36.9  220  20 11   6.1   3.4 |   4.4  39.9  235  19 10   5.8   3.2
 12000   3.7  38.7  220  20 10   7.2   4.0 |   5.2  41.4  230  20 10   5.8   3.2
 11750   4.2  39.6  215  20 10   7.5   4.1 |   5.6  42.1  225  20 10   6.3   3.4
 11500   4.7  40.5  215  20 10   7.2   3.9 |   6.0  42.8  220  20 10   6.0   3.3
 11250   5.2  41.4  210  20 10   6.6   3.6 |   6.4  43.5  220  20 11   5.3   2.9
 11000   5.6  42.1  210  21 11   6.1   3.4 |   6.8  44.2  215  21 11   4.6   2.5
 10750   6.1  43.0  205  21 11   5.8   3.2 |   7.1  44.8  210  22 11   4.3   2.4
 10500   6.4  43.5  200  22 12   5.9   3.2 |   7.3  45.1  205  23 12   4.3   2.4
 10250   6.8  44.2  200  23 12   6.0   3.3 |   7.6  45.7  205  23 12   4.2   2.3
 10000   7.3  45.1  195  24 12   6.3   3.4 |   7.9  46.2  200  24 12   4.3   2.3
  9750   7.7  45.9  190  25 13   5.0   2.7 |   8.2  46.8  200  25 13   3.7   2.1
  9500   8.2  46.8  190  26 13   3.3   1.8 |   8.7  47.7  200  27 14   3.9   2.1
  9250   8.4  47.1  190  25 13   2.6   1.4 |   9.0  48.2  200  26 14   4.3   2.3
  9000   8.6  47.5  190  24 13   4.8   2.6 |   9.3  48.7  200  26 13   3.2   1.7
  8750   9.1  48.4  190  23 12   5.0   2.8 |   9.4  48.9  195  26 14   3.6   2.0
  8500   9.3  48.7  190  22 11   2.8   1.5 |   9.8  49.6  195  25 13   6.1   3.4
  8250   9.5  49.1  190  20 10   3.3   1.8 |  10.2  50.4  195  23 12   6.2   3.4
  8000   9.7  49.5  190  18  9   2.7   1.5 |  10.7  51.3  195  22 11   7.1   3.9
  7750   9.9  49.8  190  16  8   6.6   3.6 |  11.3  52.3  190  20 10  10.0   5.5
  7500  10.7  51.3  185  13  7  14.4   7.9 |  12.1  53.8  185  17  9  11.8   6.5
  7250  11.4  52.5  180  10  5   0.2   0.1 |  12.9  55.2  185  14  7   9.6   5.3
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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