Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 010952
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Soaring Forecast
National Weather Service Pueblo, Colorado
0352 MDT Monday, June 1, 2015

This forecast is for Monday, June 1, 2015:

If the trigger temperature of 71.1 F/21.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 968 ft/min (4.9 m/s)
   Maximum height of thermals.................. 18612 ft MSL (11854 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11137 ft MSL (4380 ft AGL)
Thermal soaring outlook for Tuesday 06/02...... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:35:40 / 20:17:50 MDT
Total possible sunshine........... 14 hr 42 min 10 sec (882 min 10 sec)
Altitude of sun at 12:56:56 MDT... 73.11 degrees

Upper air data from numerical model forecast valid on 06/01/2015 at 0600 MDT

Freezing level.................. 14762 ft MSL (8004 ft AGL)
Convective condensation level... 15434 ft MSL (8676 ft AGL)
Lifted condensation level....... 15877 ft MSL (9120 ft AGL)
Lifted index.................... -4.1
K index......................... +23.5

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  -65.2 -85.4   330   21   11  -1.2  -0.7      M     M       M      M    M
 45000  -65.3 -85.5   325   28   14   4.6   2.5      M     M       M      M    M
 40000  -58.3 -72.9   295   26   13   7.4   4.0      M     M       M      M    M
 38000  -53.7 -64.7   290   25   13   7.6   4.2      M     M       M      M    M
 36000  -49.1 -56.4   285   24   12   7.6   4.2      M     M       M      M    M
 34000  -44.6 -48.3   280   23   12   7.4   4.1      M     M       M      M    M
 32000  -40.2 -40.4   275   22   11   7.4   4.1      M     M       M      M    M
 30000  -34.7 -30.5   275   20   10   8.4   4.6   34.5  94.2     7.4      M    M
 29000  -32.2 -26.0   275   20   10   8.4   4.6   34.1  93.3     7.1      M    M
 28000  -29.7 -21.5   275   19   10   8.0   4.4   33.7  92.7     6.8      M    M
 27000  -27.5 -17.5   280   17    9   7.2   4.0   32.7  90.8     6.1      M    M
 26000  -25.4 -13.7   285   16    8   7.3   4.0   31.7  89.1     5.4      M    M
 25000  -23.2  -9.8   295   14    7   7.3   4.0   30.9  87.6     4.8      M    M
 24000  -21.1  -6.0   300   14    7   7.2   3.9   29.9  85.9     4.0      M    M
 23000  -19.0  -2.2   305   14    7   7.2   3.9   29.0  84.2     3.2      M    M
 22000  -16.8   1.8   310   13    7   7.2   4.0   28.2  82.7     2.5      M    M
 21000  -14.7   5.5   315   13    7   7.4   4.1   27.3  81.1     1.7      M    M
 20000  -12.5   9.5   315   12    6   7.5   4.1   26.5  79.6     1.0      M    M
 19500  -11.4  11.5   320   11    6   7.5   4.1   26.1  79.0     0.6      M    M
 19000  -10.3  13.5   320   11    6   7.5   4.1   25.8  78.4     0.3      M    M
 18500   -9.1  15.6   325   10    5   7.5   4.1   25.4  77.7    -0.0   1164  5.9
 18000   -8.0  17.6   335   10    5   7.6   4.1   25.0  77.0    -0.3   1115  5.7
 17500   -6.9  19.6   340   10    5   7.7   4.2   24.6  76.4    -0.7   1066  5.4
 17000   -5.7  21.7   345    9    5   7.7   4.2   24.3  75.7    -1.0   1017  5.2
 16500   -4.6  23.7   350    9    5   8.3   4.5   24.0  75.2    -1.3    968  4.9
 16000   -3.4  25.9   350    8    4   8.3   4.6   23.8  74.8    -1.6    917  4.7
 15500   -2.2  28.0   350    7    4   8.5   4.6   23.5  74.4    -1.8    865  4.4
 15000   -0.3  31.5   340    6    3   8.5   4.7   23.2  73.8    -2.2    788  4.0
 14500    1.0  33.8   335    5    2   9.4   5.2   23.1  73.6    -2.4    735  3.7
 14000    2.4  36.3   340    4    2   9.6   5.3   23.1  73.5    -2.5    678  3.4
 13500    3.8  38.8   345    3    2   9.5   5.2   23.1  73.5    -2.5    621  3.2
 13000    5.1  41.2   315    3    1   9.4   5.2   23.0  73.4    -2.7    566  2.9
 12500    6.5  43.7   285    3    2   9.7   5.3   22.9  73.3    -2.8    511  2.6
 12000    7.9  46.2   260    5    2   9.2   5.1   22.9  73.2    -2.9    454  2.3
 11750    8.5  47.3   255    5    3   9.1   5.0   22.9  73.2    -2.9    426  2.2
 11500    9.2  48.6   250    6    3   9.9   5.4   22.8  73.1    -3.0    399  2.0
 11250   10.0  50.0   245    7    4   9.6   5.3   22.9  73.2    -3.0    369  1.9
 11000   10.6  51.1   245    7    4   8.4   4.6   22.8  73.0    -3.1    342  1.7
 10750   11.2  52.2   240    7    4   8.5   4.6   22.7  72.8    -3.2    316  1.6
 10500   11.9  53.4   240    7    4   8.6   4.7   22.6  72.7    -3.3    290  1.5
 10250   12.5  54.5   240    7    4   9.0   5.0   22.5  72.6    -3.4    263  1.3
 10000   13.2  55.8   235    7    4   9.0   4.9   22.5  72.5    -3.5    236  1.2
  9750   13.8  56.8   235    7    4   9.0   5.0   22.4  72.4    -3.5    209  1.1
  9500   14.5  58.1   235    7    4   8.6   4.7   22.4  72.2    -3.6    181  0.9
  9250   15.1  59.2   235    7    4   7.9   4.3   22.2  72.0    -3.7    156  0.8
  9000   15.7  60.3   235    7    4   7.6   4.2   22.1  71.8    -3.9    131  0.7
  8750   16.2  61.2   240    7    4   8.1   4.5   21.9  71.5    -4.1    107  0.5
  8500   16.8  62.2   240    7    4   5.0   2.7   21.7  71.1    -4.3     83  0.4
  8250   17.0  62.6   245    7    4   1.2   0.7   21.2  70.1    -4.8     71  0.4
  8000   17.1  62.8   250    7    4   2.3   1.3   20.6  69.0    -5.5     60  0.3
  7750   17.2  63.0   255    7    4  -0.6  -0.3   20.0  67.9    -6.1     49  0.3
  7500   16.5  61.7   260    9    5 -18.0  -9.9   18.7  65.7    -7.5     63  0.3
  7250   14.4  57.9   265    8    4 -30.1 -16.5   16.4  61.5    -9.9    116  0.6
  7000   12.4  54.3   275    8    4 -21.2 -11.6   14.0  57.3   -12.2    169  0.9
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           06/01/2015 at 0900 MDT          |       06/01/2015 at 1200 MDT
                                           |
K index... +22.1  LI... +270.6             | K index... +25.0  LI... +270.6
CAPE... +404.4  CIN... -33.2               | CAPE... +489.1  CIN... -4.9
                                           |
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 -64.9 -84.8  310  15  8  -0.6  -0.3 | -64.8 -84.6  290  16  8  -0.6  -0.3
 45000 -64.4 -83.9  315  18  9   4.1   2.2 | -64.1 -83.4  280  17  9   4.1   2.2
 40000 -58.0 -72.4  295  20 11   7.1   3.9 | -57.9 -72.2  280  23 12   7.3   4.0
 38000 -53.6 -64.5  295  20 10   7.5   4.1 | -53.3 -63.9  285  22 11   7.6   4.2
 36000 -49.1 -56.4  290  20 10   7.5   4.1 | -48.7 -55.7  285  21 11   7.6   4.2
 34000 -44.6 -48.3  285  20 10   7.4   4.1 | -44.2 -47.6  285  20 10   7.5   4.1
 32000 -39.6 -39.3  280  19 10   7.3   4.0 | -39.1 -38.4  280  17  9   7.4   4.1
 30000 -34.7 -30.5  270  19 10   8.4   4.6 | -34.4 -29.9  265  17  9   7.9   4.4
 29000 -32.2 -26.0  270  19 10   8.4   4.6 | -32.1 -25.8  260  18  9   8.0   4.4
 28000 -29.6 -21.3  265  19 10   8.2   4.5 | -29.7 -21.5  255  19 10   7.9   4.3
 27000 -27.3 -17.1  270  17  9   7.8   4.3 | -27.4 -17.3  255  18  9   7.8   4.3
 26000 -25.0 -13.0  270  16  8   7.8   4.3 | -25.1 -13.2  255  17  9   7.8   4.3
 25000 -22.6  -8.7  275  15  8   8.0   4.4 | -22.7  -8.9  260  16  8   7.9   4.3
 24000 -20.5  -4.9  280  13  7   6.9   3.8 | -20.6  -5.1  265  15  8   7.0   3.8
 23000 -18.5  -1.3  285  12  6   6.9   3.8 | -18.5  -1.3  265  13  7   7.0   3.8
 22000 -16.4   2.5  295  11  5   6.9   3.8 | -16.5   2.3  270  12  6   7.0   3.8
 21000 -14.4   6.1  300  11  5   6.8   3.8 | -14.3   6.3  280  11  6   7.5   4.1
 20000 -12.4   9.7  305  11  6   6.9   3.8 | -12.1  10.2  290  12  6   7.5   4.1
 19500 -11.4  11.5  305  11  6   6.8   3.7 | -11.0  12.2  295  12  6   7.5   4.1
 19000 -10.3  13.5  310  11  6   7.9   4.3 |  -9.9  14.2  295  12  6   7.8   4.3
 18500  -9.1  15.6  305  11  6   8.0   4.4 |  -8.7  16.3  295  12  6   7.8   4.3
 18000  -7.9  17.8  305  11  5   8.0   4.4 |  -7.6  18.3  290  11  6   7.9   4.3
 17500  -6.7  19.9  305  10  5   7.9   4.4 |  -6.4  20.5  290  11  6   8.0   4.4
 17000  -5.6  21.9  305   9  5   7.9   4.3 |  -5.2  22.6  285  11  6   8.0   4.4
 16500  -4.4  24.1  310   8  4   8.6   4.7 |  -4.1  24.6  280  10  5   7.9   4.3
 16000  -3.1  26.4  310   7  4   8.6   4.7 |  -2.9  26.8  280   9  5   7.9   4.3
 15500  -1.2  29.8  305   6  3   8.8   4.8 |  -1.2  29.8  275   8  4   8.1   4.4
 15000   0.1  32.2  300   6  3   8.8   4.8 |  -0.0  32.0  270   7  3   8.1   4.4
 14500   1.4  34.5  290   5  3   9.0   5.0 |   1.2  34.2  265   5  3   9.0   4.9
 14000   2.7  36.9  280   5  2   9.1   5.0 |   2.5  36.5  255   5  3   9.3   5.1
 13500   4.0  39.2  265   4  2   9.4   5.1 |   3.9  39.0  250   5  2   9.6   5.3
 13000   5.4  41.7  255   4  2   9.5   5.2 |   5.3  41.5  245   4  2   9.8   5.4
 12500   6.8  44.2  240   4  2   8.5   4.6 |   6.8  44.2  240   4  2   9.2   5.1
 12000   8.1  46.6  240   4  2   9.8   5.4 |   8.2  46.8  230   4  2   9.8   5.4
 11750   8.8  47.8  245   4  2   9.7   5.3 |   8.9  48.0  225   4  2   9.6   5.3
 11500   9.5  49.1  245   5  2   8.8   4.8 |   9.6  49.3  220   4  2   9.4   5.2
 11250  10.1  50.2  240   5  3   8.5   4.7 |  10.3  50.5  210   4  2   9.6   5.3
 11000  10.8  51.4  245   5  3   9.4   5.1 |  11.0  51.8  205   4  2  10.1   5.5
 10750  11.5  52.7  245   5  3   9.4   5.2 |  11.8  53.2  200   5  2  10.1   5.6
 10500  12.2  54.0  250   5  3   9.0   4.9 |  12.5  54.5  200   5  2   9.7   5.3
 10250  12.8  55.0  255   5  2   7.8   4.3 |  13.1  55.6  195   5  3   8.3   4.6
 10000  13.4  56.1  255   5  2   8.5   4.7 |  13.8  56.8  195   5  3   9.5   5.2
  9750  14.1  57.4  255   5  2   9.7   5.3 |  14.5  58.1  190   5  3  10.9   6.0
  9500  14.8  58.6  255   5  2   8.8   4.8 |  15.3  59.5  190   6  3  10.1   5.5
  9250  15.4  59.7  255   4  2   7.5   4.1 |  16.0  60.8  185   6  3   9.2   5.1
  9000  15.9  60.6  255   4  2   7.5   4.1 |  16.7  62.1  185   6  3   9.4   5.1
  8750  16.5  61.7  250   4  2   8.7   4.8 |  17.4  63.3  185   6  3  10.7   5.9
  8500  17.2  63.0  250   4  2   8.6   4.7 |  18.3  64.9  185   6  3  10.9   6.0
  8250  17.7  63.9  250   4  2   7.7   4.2 |  19.1  66.4  180   6  3  10.3   5.7
  8000  18.2  64.8  250   4  2   7.8   4.3 |  19.8  67.6  180   6  3  10.4   5.7
  7750  18.7  65.7  250   4  2   8.0   4.4 |  20.6  69.1  180   6  3  10.4   5.7
  7500  19.2  66.6  245   4  2   8.2   4.5 |  21.4  70.5  180   6  3  11.1   6.1
  7250  19.7  67.5  245   4  2   8.1   4.5 |  22.2  72.0  180   6  3  11.7   6.4
  7000  20.2  68.4  240   3  2   8.4   4.6 |  23.0  73.4  175   6  3  11.3   6.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           06/01/2015 at 1500 MDT          |       06/01/2015 at 1800 MDT
                                           |
K index... +27.4  LI... +272.1             | K index... +30.1  LI... +271.7
CAPE... +164.7  CIN... -36.4               | CAPE... +286.3  CIN... -28.0
                                           |
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 -64.9 -84.8  280  17  9  -0.8  -0.4 | -64.2 -83.6  280  16  8  -1.1  -0.6
 45000 -64.6 -84.3  260  21 11   3.9   2.1 | -64.6 -84.3  255  24 12   3.2   1.7
 40000 -58.6 -73.5  270  26 13   7.9   4.3 | -59.5 -75.1  260  27 14   8.4   4.6
 38000 -53.8 -64.8  270  24 12   8.0   4.4 | -54.3 -65.7  260  27 14   8.7   4.8
 36000 -49.0 -56.2  265  22 11   8.0   4.4 | -49.1 -56.4  260  27 14   8.7   4.8
 34000 -43.2 -45.8  260  21 11   8.8   4.9 | -43.1 -45.6  260  25 13   8.8   4.8
 32000 -37.9 -36.2  255  22 11   8.7   4.8 | -37.8 -36.0  260  21 11   8.7   4.8
 30000 -32.9 -27.2  260  22 11   8.1   4.5 | -32.8 -27.0  265  20 10   8.4   4.6
 29000 -30.5 -22.9  265  21 11   8.1   4.5 | -30.3 -22.5  270  19 10   8.4   4.6
 28000 -28.1 -18.6  265  21 11   7.8   4.3 | -27.7 -17.9  270  19 10   8.1   4.4
 27000 -25.9 -14.6  270  20 11   7.3   4.0 | -25.5 -13.9  275  18  9   7.5   4.1
 26000 -23.7 -10.7  275  20 10   7.3   4.0 | -23.3  -9.9  285  17  9   7.5   4.1
 25000 -21.5  -6.7  280  19 10   7.4   4.0 | -21.1  -6.0  290  17  9   7.5   4.1
 24000 -19.4  -2.9  285  19 10   7.0   3.9 | -18.9  -2.0  290  16  8   7.6   4.1
 23000 -17.4   0.7  285  19 10   7.1   3.9 | -16.7   1.9  295  15  8   7.6   4.2
 22000 -15.3   4.5  290  18 10   7.1   3.9 | -14.4   6.1  295  14  7   7.7   4.2
 21000 -13.1   8.4  290  18  9   7.4   4.1 | -12.5   9.5  295  12  6   6.5   3.6
 20000 -11.0  12.2  290  16  8   7.5   4.1 | -10.6  12.9  295  10  5   6.5   3.6
 19500  -9.9  14.2  290  16  8   7.5   4.1 |  -9.6  14.7  300   9  5   6.6   3.6
 19000  -8.8  16.2  290  15  8   6.9   3.8 |  -8.7  16.3  300   8  4   6.4   3.5
 18500  -7.8  18.0  295  13  7   6.8   3.7 |  -7.7  18.1  295   7  4   6.3   3.5
 18000  -6.8  19.8  295  11  5   6.8   3.7 |  -6.8  19.8  295   7  3   6.4   3.5
 17500  -5.9  21.4  300   9  5   6.7   3.7 |  -5.9  21.4  285   6  3   6.5   3.5
 17000  -4.9  23.2  305   7  4   6.7   3.7 |  -5.0  23.0  275   7  3   6.5   3.6
 16500  -3.9  25.0  310   5  3   6.9   3.8 |  -3.6  25.5  265   7  4   6.2   3.4
 16000  -2.4  27.7  310   3  2   6.9   3.8 |  -2.7  27.1  255   7  4   6.3   3.4
 15500  -1.3  29.7  300   2  1   7.4   4.1 |  -1.8  28.8  245   7  4   6.3   3.4
 15000  -0.3  31.5  265   1  1   7.4   4.1 |  -0.9  30.4  240   8  4   6.3   3.5
 14500   0.8  33.4  215   1  1   7.5   4.1 |   0.0  32.0  240   9  4   7.4   4.1
 14000   1.9  35.4  200   2  1   7.6   4.2 |   1.2  34.2  235   9  5   8.0   4.4
 13500   3.1  37.6  190   3  2   8.2   4.5 |   2.4  36.3  235  10  5   8.8   4.8
 13000   4.4  39.9  190   4  2   8.8   4.9 |   3.9  39.0  230  11  5   9.9   5.4
 12500   5.7  42.3  190   5  2   8.7   4.8 |   5.4  41.7  230  11  6   8.8   4.8
 12000   7.0  44.6  190   6  3   9.0   4.9 |   6.6  43.9  230  12  6   9.4   5.2
 11750   7.6  45.7  190   6  3   8.9   4.9 |   7.3  45.1  225  12  6   9.2   5.1
 11500   8.3  46.9  190   7  3   9.0   4.9 |   8.0  46.4  225  12  6   8.9   4.9
 11250   8.9  48.0  190   7  4   8.7   4.7 |   8.6  47.5  225  12  6   8.3   4.6
 11000   9.6  49.3  195   8  4   8.2   4.5 |   9.3  48.7  225  13  7   8.4   4.6
 10750  10.2  50.4  190   9  5   8.2   4.5 |   9.9  49.8  225  13  7   8.5   4.7
 10500  10.8  51.4  190  10  5   8.3   4.5 |  10.5  50.9  220  13  7   8.4   4.6
 10250  11.4  52.5  195  10  5   8.6   4.7 |  11.1  52.0  220  14  7   8.1   4.4
 10000  12.0  53.6  195  11  5   8.1   4.5 |  11.7  53.1  220  14  7   8.3   4.6
  9750  12.6  54.7  195  12  6   7.5   4.1 |  12.3  54.1  220  14  7   8.7   4.8
  9500  13.2  55.8  195  12  6   7.9   4.3 |  13.0  55.4  220  15  8   8.5   4.6
  9250  13.8  56.8  195  13  7   8.5   4.7 |  13.6  56.5  220  15  8   8.2   4.5
  9000  14.4  57.9  195  13  7   8.3   4.6 |  14.2  57.6  220  15  8   8.1   4.5
  8750  15.0  59.0  195  14  7   6.0   3.3 |  14.8  58.6  220  15  8   8.2   4.5
  8500  15.3  59.5  195  15  8   6.5   3.5 |  15.4  59.7  220  15  8   8.1   4.4
  8250  15.9  60.6  200  15  8   8.7   4.8 |  16.0  60.8  220  15  8   8.0   4.4
  8000  16.5  61.7  200  15  8   8.9   4.9 |  16.5  61.7  220  14  7   7.7   4.2
  7750  17.1  62.8  200  15  8   8.1   4.5 |  17.1  62.8  220  14  7   8.8   4.8
  7500  17.6  63.7  200  16  8   7.3   4.0 |  17.6  63.7  225  13  7   7.5   4.1
  7250  18.1  64.6  200  15  8   7.7   4.2 |  18.0  64.4  225  12  6   4.9   2.7
  7000  18.6  65.5  200  14  7   7.4   4.1 |  18.4  65.1  225  11  6   7.0   3.9
  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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