Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 021025
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0425 MDT Tuesday, June 2, 2015

This forecast is for Tuesday, June 2, 2015:

If the trigger temperature of 74.1 F/23.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1361 ft/min (6.9 m/s)
   Maximum height of thermals.................. 20219 ft MSL (13461 ft AGL)

Forecast maximum temperature................... 80.0 F/27.1 C
Time of trigger temperature.................... 1045 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................. 11314 ft MSL (4556 ft AGL)
Thermal soaring outlook for Wednesday 06/03.... Good

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 05:35:17 / 20:18:32 MDT
Total possible sunshine........... 14 hr 43 min 14 sec (883 min 14 sec)
Altitude of sun at 12:57:05 MDT... 73.24 degrees

Upper air data from numerical model forecast valid on 06/02/2015 at 0600 MDT

Freezing level.................. 15240 ft MSL (8482 ft AGL)
Convective condensation level... 17811 ft MSL (11053 ft AGL)
Lifted condensation level....... 18236 ft MSL (11479 ft AGL)
Lifted index.................... -1.6
K index......................... +6.5

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  -63.5 -82.3   305   21   11   1.1   0.6      M     M       M      M    M
 45000  -61.4 -78.5   295   30   16   2.8   1.6      M     M       M      M    M
 40000  -56.7 -70.1   280   33   17   6.1   3.3      M     M       M      M    M
 38000  -53.1 -63.6   270   34   17   6.1   3.3      M     M       M      M    M
 36000  -49.5 -57.1   265   36   19   6.1   3.4      M     M       M      M    M
 34000  -44.8 -48.6   260   34   18   8.5   4.7      M     M       M      M    M
 32000  -39.7 -39.5   260   31   16   8.5   4.7      M     M       M      M    M
 30000  -34.8 -30.6   260   28   15   8.2   4.5   35.0  95.0     6.4      M    M
 29000  -32.3 -26.1   265   27   14   8.2   4.5   34.4  93.9     6.0      M    M
 28000  -29.3 -20.7   265   25   13   8.1   4.4   33.8  92.9     5.6      M    M
 27000  -26.9 -16.4   270   24   12   8.0   4.4   33.0  91.5     5.1      M    M
 26000  -24.5 -12.1   270   23   12   8.0   4.4   32.4  90.3     4.6      M    M
 25000  -22.1  -7.8   270   22   11   8.1   4.5   31.8  89.3     4.2      M    M
 24000  -20.0  -4.0   270   20   10   6.8   3.7   30.8  87.5     3.4      M    M
 23000  -17.9  -0.2   265   18    9   6.8   3.7   29.7  85.5     2.5      M    M
 22000  -15.9   3.4   265   16    8   6.8   3.7   28.8  83.8     1.7      M    M
 21000  -14.0   6.8   265   16    8   6.6   3.6   27.6  81.7     0.8      M    M
 20000  -12.0  10.4   265   16    8   6.6   3.6   26.5  79.8    -0.2   1343  6.8
 19500  -11.0  12.2   270   16    8   6.6   3.6   26.0  78.9    -0.6   1298  6.6
 19000  -10.0  14.0   270   16    8   7.7   4.2   25.6  78.1    -1.0   1253  6.4
 18500   -8.8  16.2   265   18    9   8.0   4.4   25.3  77.5    -1.4   1204  6.1
 18000   -7.7  18.1   265   19   10   8.2   4.5   25.0  77.0    -1.7   1154  5.9
 17500   -6.4  20.5   265   19   10   9.0   4.9   24.8  76.7    -1.9   1101  5.6
 17000   -5.1  22.8   265   19   10   8.9   4.9   24.7  76.4    -2.0   1047  5.3
 16500   -3.7  25.3   270   18    9   9.1   5.0   24.6  76.2    -2.1    992  5.0
 16000   -2.4  27.7   270   18    9   9.1   5.0   24.4  76.0    -2.3    937  4.8
 15500   -1.0  30.2   270   18    9   9.3   5.1   24.3  75.8    -2.4    881  4.5
 15000    0.4  32.7   270   17    9   9.5   5.2   24.3  75.7    -2.5    824  4.2
 14500    1.8  35.2   270   17    9   9.6   5.2   24.3  75.7    -2.5    767  3.9
 14000    3.9  39.0   270   17    9   9.7   5.3   24.2  75.6    -2.6    681  3.5
 13500    5.4  41.7   270   17    9   9.8   5.4   24.2  75.6    -2.6    623  3.2
 13000    6.8  44.2   270   17    9   9.8   5.4   24.3  75.7    -2.6    564  2.9
 12500    8.3  46.9   270   17    9   8.3   4.6   24.3  75.7    -2.6    506  2.6
 12000    9.5  49.1   270   17    9   9.7   5.3   24.1  75.3    -2.9    454  2.3
 11750   10.2  50.4   270   17    9   9.4   5.2   24.0  75.2    -2.9    426  2.2
 11500   10.9  51.6   270   18    9   9.1   5.0   24.0  75.2    -3.0    398  2.0
 11250   11.6  52.9   270   18    9   9.1   5.0   23.9  75.1    -3.0    371  1.9
 11000   12.2  54.0   270   18    9   9.6   5.3   23.9  75.1    -3.1    343  1.7
 10750   12.9  55.2   270   18    9   9.5   5.2   23.9  75.0    -3.1    315  1.6
 10500   13.6  56.5   265   18    9   9.4   5.2   23.9  75.0    -3.2    286  1.5
 10250   14.3  57.7   265   18    9   7.0   3.9   23.8  74.8    -3.3    260  1.3
 10000   14.7  58.5   265   18    9   7.7   4.2   23.6  74.4    -3.6    239  1.2
  9750   15.4  59.7   265   18    9   9.7   5.3   23.5  74.3    -3.7    212  1.1
  9500   16.0  60.8   260   18    9   9.1   5.0   23.5  74.3    -3.7    185  0.9
  9250   16.7  62.1   260   18    9   8.6   4.7   23.4  74.2    -3.8    159  0.8
  9000   17.2  63.0   260   18    9   7.8   4.3   23.3  73.9    -4.0    135  0.7
  8750   17.7  63.9   255   18    9   8.0   4.4   23.1  73.7    -4.2    112  0.6
  8500   18.2  64.8   255   18    9   6.2   3.4   23.0  73.3    -4.5     90  0.5
  8250   18.4  65.1   255   18    9   2.0   1.1   22.5  72.6    -5.0     76  0.4
  8000   18.4  65.1   250   17    9  -2.9  -1.6   21.8  71.2    -5.9     71  0.4
  7750   18.3  64.9   250   16    8   7.8   4.3   21.0  69.9    -6.7     66  0.3
  7500   18.8  65.8   250   15    8  -3.9  -2.1   20.9  69.7    -6.9     42  0.2
  7250   17.0  62.6   255   13    7 -36.1 -19.8   18.8  65.8    -9.1     89  0.5
  7000   14.2  57.6   260   10    5 -33.1 -18.2   15.7  60.3   -12.3    168  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           06/02/2015 at 0900 MDT          |       06/02/2015 at 1200 MDT
                                           |
K index... +1.9  LI... +274.4              | K index... +4.9  LI... +273.8
CAPE... 0.0  CIN... M                      | CAPE... +15.8  CIN... -80.2
                                           |
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  305  19 10   0.8   0.4 | -63.7 -82.7  305  14  7   0.9   0.5
 45000 -61.9 -79.4  295  25 13   3.3   1.8 | -61.6 -78.9  290  21 11   3.4   1.9
 40000 -56.5 -69.7  290  34 17   5.9   3.3 | -56.0 -68.8  285  34 17   5.7   3.1
 38000 -52.9 -63.2  280  33 17   5.9   3.3 | -52.6 -62.7  280  32 16   5.7   3.1
 36000 -49.4 -56.9  270  34 17   6.0   3.3 | -49.1 -56.4  270  31 16   5.8   3.2
 34000 -44.8 -48.6  265  29 15   8.2   4.5 | -44.6 -48.3  265  28 14   8.2   4.5
 32000 -39.9 -39.8  265  22 11   8.3   4.5 | -39.7 -39.5  260  25 13   8.2   4.5
 30000 -35.0 -31.0  265  21 11   8.3   4.5 | -35.2 -31.4  255  23 12   7.2   3.9
 29000 -32.5 -26.5  265  22 11   8.3   4.5 | -32.5 -26.5  255  23 12   7.2   3.9
 28000 -29.4 -20.9  265  23 12   8.2   4.5 | -30.4 -22.7  255  23 12   7.7   4.2
 27000 -27.0 -16.6  270  22 11   8.0   4.4 | -27.8 -18.0  260  23 12   8.6   4.7
 26000 -24.6 -12.3  270  20 10   8.0   4.4 | -25.2 -13.4  260  22 11   8.6   4.7
 25000 -22.2  -8.0  275  19 10   8.1   4.4 | -22.7  -8.9  265  21 11   8.7   4.8
 24000 -19.9  -3.8  275  18  9   7.5   4.1 | -20.2  -4.4  260  20 10   7.9   4.4
 23000 -17.7   0.1  270  16  8   7.5   4.1 | -17.8  -0.0  255  18  9   7.9   4.4
 22000 -15.4   4.3  265  15  8   7.5   4.1 | -15.5   4.1  250  17  9   7.9   4.4
 21000 -13.3   8.1  265  15  8   6.8   3.7 | -13.3   8.1  250  17  9   7.0   3.8
 20000 -11.3  11.7  265  15  8   6.8   3.7 | -11.2  11.8  250  17  9   7.0   3.8
 19500 -10.3  13.5  260  16  8   6.8   3.7 | -10.2  13.6  250  17  9   7.0   3.8
 19000  -9.2  15.4  260  16  8   7.8   4.3 |  -9.1  15.6  250  17  9   7.6   4.2
 18500  -8.0  17.6  260  17  8   8.1   4.4 |  -8.0  17.6  250  17  9   7.8   4.3
 18000  -6.8  19.8  265  17  9   8.0   4.4 |  -6.8  19.8  250  17  9   7.9   4.3
 17500  -5.7  21.7  260  18  9   7.6   4.1 |  -5.6  21.9  255  17  9   8.4   4.6
 17000  -4.6  23.7  255  18 10   7.6   4.2 |  -4.4  24.1  255  18  9   8.4   4.6
 16500  -3.4  25.9  250  19 10   8.7   4.8 |  -3.1  26.4  255  19 10   8.2   4.5
 16000  -2.1  28.2  250  19 10   8.9   4.9 |  -2.0  28.4  255  20 10   8.3   4.5
 15500  -0.8  30.6  250  18  9   9.1   5.0 |  -0.8  30.6  255  20 10   8.5   4.7
 15000   0.5  32.9  245  17  9   9.2   5.1 |   0.4  32.7  255  19 10   8.7   4.8
 14500   1.9  35.4  240  16  8   9.3   5.1 |   2.3  36.1  255  17  9   9.3   5.1
 14000   4.0  39.2  240  15  8   9.2   5.1 |   3.7  38.7  255  16  8   9.5   5.2
 13500   5.3  41.5  240  14  7   9.2   5.1 |   5.1  41.2  255  15  8   9.6   5.3
 13000   6.7  44.1  245  14  7   9.2   5.1 |   6.5  43.7  255  13  7   9.8   5.4
 12500   8.1  46.6  250  14  7   7.6   4.2 |   8.0  46.4  250  12  6   8.7   4.8
 12000   9.2  48.6  260  14  7   9.0   4.9 |   9.3  48.7  250  10  5   9.8   5.4
 11750   9.9  49.8  260  14  7   8.7   4.8 |  10.0  50.0  250   9  5   9.6   5.3
 11500  10.5  50.9  265  14  7   8.3   4.5 |  10.7  51.3  255   9  4   9.3   5.1
 11250  11.1  52.0  265  14  7   8.3   4.5 |  11.4  52.5  250   8  4   9.5   5.2
 11000  11.7  53.1  270  14  7   8.9   4.9 |  12.1  53.8  250   8  4   9.9   5.4
 10750  12.4  54.3  275  14  7   8.7   4.8 |  12.8  55.0  250   8  4   9.9   5.4
 10500  13.0  55.4  280  14  7   8.7   4.8 |  13.6  56.5  250   8  4   9.7   5.3
 10250  13.6  56.5  280  14  7   7.5   4.1 |  14.2  57.6  250   7  4   8.2   4.5
 10000  14.1  57.4  285  14  7   8.2   4.5 |  14.9  58.8  250   7  4   9.6   5.2
  9750  14.8  58.6  285  14  7   9.4   5.2 |  15.7  60.3  250   7  4  11.4   6.3
  9500  15.5  59.9  290  14  7   9.0   4.9 |  16.5  61.7  250   7  4  10.7   5.9
  9250  16.1  61.0  290  14  7   8.2   4.5 |  17.3  63.1  250   7  4   9.6   5.3
  9000  16.7  62.1  290  15  8   7.9   4.3 |  17.9  64.2  250   7  3   9.3   5.1
  8750  17.3  63.1  290  16  8   9.1   5.0 |  18.7  65.7  250   7  3  10.3   5.7
  8500  18.0  64.4  290  17  9   8.8   4.8 |  19.5  67.1  250   6  3  10.6   5.8
  8250  18.5  65.3  290  17  9   6.8   3.7 |  20.2  68.4  250   6  3  10.4   5.7
  8000  18.9  66.0  290  16  8   6.1   3.3 |  21.0  69.8  250   6  3  10.8   5.9
  7750  19.3  66.7  290  16  8   6.9   3.8 |  21.8  71.2  250   6  3   9.3   5.1
  7500  19.7  67.5  285  14  7   6.4   3.5 |  22.4  72.3  250   5  3   9.6   5.3
  7250  20.0  68.0  285  12  6   5.1   2.8 |  23.2  73.8  250   5  3  12.4   6.8
  7000  20.3  68.5  285  11  5   5.5   3.0 |  24.1  75.4  250   5  3  11.9   6.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/02/2015 at 1500 MDT          |       06/02/2015 at 1800 MDT
                                           |
K index... +20.3  LI... +272.9             | K index... +19.4  LI... +272.8
CAPE... +114.8  CIN... -18.6               | CAPE... +168.0  CIN... -22.2
                                           |
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 -63.4 -82.1  275  13  7   1.8   1.0 | -63.7 -82.7  280  15  8   0.9   0.5
 45000 -60.3 -76.5  270  21 11   3.4   1.8 | -61.4 -78.5  275  22 11   4.2   2.3
 40000 -54.9 -66.8  285  34 17   5.3   2.9 | -54.8 -66.6  285  33 17   5.3   2.9
 38000 -51.7 -61.1  280  33 17   5.3   2.9 | -51.6 -60.9  275  36 19   5.2   2.9
 36000 -48.5 -55.3  270  34 17   5.4   2.9 | -48.5 -55.3  265  40 21   5.3   2.9
 34000 -44.2 -47.6  265  33 17   8.0   4.4 | -44.1 -47.4  265  40 21   8.1   4.5
 32000 -39.4 -38.9  260  33 17   8.0   4.4 | -39.3 -38.7  270  38 20   8.1   4.5
 30000 -34.9 -30.8  255  31 16   7.1   3.9 | -34.7 -30.5  270  36 19   7.2   4.0
 29000 -32.3 -26.1  255  29 15   7.1   3.9 | -32.0 -25.6  270  34 18   7.2   4.0
 28000 -30.2 -22.4  255  27 14   7.3   4.0 | -29.9 -21.8  270  33 17   7.1   3.9
 27000 -27.9 -18.2  255  27 14   7.9   4.3 | -27.8 -18.0  270  31 16   6.9   3.8
 26000 -25.5 -13.9  260  26 13   7.9   4.3 | -25.7 -14.3  270  28 15   6.9   3.8
 25000 -23.1  -9.6  260  25 13   7.9   4.4 | -23.7 -10.7  270  26 13   6.8   3.7
 24000 -20.9  -5.6  260  24 13   7.3   4.0 | -21.3  -6.3  270  24 12   8.1   4.4
 23000 -18.7  -1.7  255  24 12   7.4   4.0 | -19.0  -2.2  275  23 12   8.1   4.4
 22000 -16.5   2.3  255  23 12   7.3   4.0 | -16.6   2.1  275  21 11   8.1   4.4
 21000 -14.2   6.4  255  22 11   8.1   4.5 | -14.1   6.6  275  20 10   8.6   4.7
 20000 -11.8  10.8  260  21 11   8.2   4.5 | -11.5  11.3  275  20 10   8.7   4.8
 19500 -10.6  12.9  260  21 11   8.3   4.5 | -10.3  13.5  275  19 10   8.8   4.8
 19000  -9.4  15.1  265  20 10   8.7   4.8 |  -9.0  15.8  275  19 10   8.9   4.9
 18500  -8.1  17.4  265  18  9   8.8   4.8 |  -7.7  18.1  275  17  9   9.0   4.9
 18000  -6.9  19.6  265  16  8   8.9   4.9 |  -6.4  20.5  275  16  8   9.0   4.9
 17500  -5.6  21.9  265  15  8   9.1   5.0 |  -5.0  23.0  275  15  8   9.1   5.0
 17000  -4.2  24.4  265  13  7   9.1   5.0 |  -3.7  25.3  275  14  7   9.1   5.0
 16500  -2.9  26.8  265  12  6   9.3   5.1 |  -2.3  27.9  275  13  7   9.6   5.3
 16000  -1.5  29.3  265  11  6   9.3   5.1 |  -0.9  30.4  275  13  6   9.7   5.3
 15500  -0.1  31.8  265  11  5   9.4   5.2 |   0.6  33.1  275  12  6   9.6   5.3
 15000   1.3  34.3  265  10  5   9.6   5.3 |   2.0  35.6  275  12  6   9.4   5.2
 14500   3.4  38.1  265   9  5   9.6   5.2 |   3.4  38.1  275  11  6   9.4   5.2
 14000   4.9  40.8  260   8  4   9.5   5.2 |   5.5  41.9  270  10  5   9.5   5.2
 13500   6.3  43.3  255   8  4   9.8   5.4 |   6.9  44.4  270   9  5   9.4   5.2
 13000   7.8  46.0  250   7  4  10.2   5.6 |   8.3  46.9  265   9  5   9.2   5.0
 12500   9.2  48.6  245   7  3   8.4   4.6 |   9.7  49.5  260   8  4   9.9   5.4
 12000  10.5  50.9  235   6  3   9.8   5.4 |  11.1  52.0  260   8  4   9.4   5.2
 11750  11.2  52.2  230   6  3   9.7   5.3 |  11.8  53.2  255   8  4  10.1   5.5
 11500  12.0  53.6  225   6  3   8.7   4.8 |  12.6  54.7  255   7  4   8.1   4.5
 11250  12.6  54.7  220   7  3   8.9   4.9 |  13.1  55.6  250   8  4   8.2   4.5
 11000  13.3  55.9  215   7  3  10.1   5.5 |  13.8  56.8  245   7  4  10.1   5.5
 10750  14.0  57.2  210   7  3   9.8   5.4 |  14.5  58.1  240   7  4   9.6   5.2
 10500  14.8  58.6  205   7  4   9.8   5.4 |  15.3  59.5  235   7  4   9.8   5.4
 10250  15.5  59.9  205   7  4   8.6   4.7 |  15.9  60.6  230   7  4   7.3   4.0
 10000  16.1  61.0  205   7  4   9.5   5.2 |  16.4  61.5  225   8  4   8.0   4.4
  9750  16.9  62.4  200   7  4  11.0   6.0 |  17.1  62.8  220   8  4  10.4   5.7
  9500  17.7  63.9  200   7  4  10.6   5.8 |  17.9  64.2  210   8  4   9.8   5.4
  9250  18.4  65.1  195   7  4   9.4   5.2 |  18.6  65.5  210   8  4   9.2   5.0
  9000  19.1  66.4  195   7  4   9.1   5.0 |  19.2  66.6  205   8  4   9.0   4.9
  8750  19.9  67.8  195   7  4  10.6   5.8 |  19.9  67.8  200   8  4  10.0   5.5
  8500  20.6  69.1  195   8  4  10.9   6.0 |  20.7  69.3  200   9  4  10.2   5.6
  8250  21.4  70.5  190   8  4  10.2   5.6 |  21.4  70.5  195   9  4   9.9   5.4
  8000  22.2  72.0  190   8  4  10.2   5.6 |  22.1  71.8  195   9  4  10.0   5.5
  7750  22.9  73.2  190   8  4   9.2   5.1 |  22.9  73.2  195   8  4   9.1   5.0
  7500  23.6  74.5  190   8  4   9.4   5.1 |  23.5  74.3  190   8  4   7.7   4.2
  7250  24.3  75.7  190   7  4  11.9   6.5 |  24.0  75.2  190   8  4   7.2   4.0
  7000  25.2  77.4  190   7  4  12.6   6.9 |  24.4  75.9  190   8  4   6.6   3.6
  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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