Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 221129
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0529 MDT Wednesday, April 22, 2015

This forecast is for Wednesday, April 22, 2015:

If the trigger temperature of 52.0 F/11.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 711 ft/min (3.6 m/s)
   Maximum height of thermals.................. 16762 ft MSL (10004 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11473 ft MSL (4716 ft AGL)
Thermal soaring outlook for Thursday 04/23..... Good

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

Remarks...

Sunrise/Sunset.................... 06:12:59 / 19:41:50 MDT
Total possible sunshine........... 13 hr 28 min 51 sec (808 min 51 sec)
Altitude of sun at 12:57:34 MDT... 63.33 degrees

Upper air data from numerical model forecast valid on 04/22/2015 at 0600 MDT

Freezing level.................. 11065 ft MSL (4307 ft AGL)
Convective condensation level... 13806 ft MSL (7048 ft AGL)
Lifted condensation level....... 13874 ft MSL (7116 ft AGL)
Lifted index.................... -4.1
K index......................... +19.0

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  -58.4 -73.1   270   38   19   0.8   0.5      M     M       M      M    M
 45000  -57.2 -71.0   265   42   22   1.3   0.7      M     M       M      M    M
 40000  -61.8 -79.2   265   18    9  -3.1  -1.7      M     M       M      M    M
 38000  -61.2 -78.2   275   12    6   5.4   3.0      M     M       M      M    M
 36000  -57.9 -72.2   295   12    6   5.4   3.0      M     M       M      M    M
 34000  -54.5 -66.1   305   14    7   7.4   4.1      M     M       M      M    M
 32000  -50.2 -58.4   285   18    9   7.3   4.0      M     M       M      M    M
 30000  -45.8 -50.4   275   22   11   7.8   4.3   24.0  75.3     6.5      M    M
 29000  -43.5 -46.3   275   22   12   7.8   4.3   23.2  73.7     5.9      M    M
 28000  -41.1 -42.0   275   23   12   7.8   4.3   22.4  72.4     5.4      M    M
 27000  -38.2 -36.8   275   23   12   7.9   4.3   21.6  71.0     4.9      M    M
 26000  -35.9 -32.6   275   22   11   7.9   4.4   20.8  69.5     4.3      M    M
 25000  -33.5 -28.3   280   21   11   7.9   4.4   20.2  68.3     3.8      M    M
 24000  -31.1 -24.0   280   20   10   8.0   4.4   19.7  67.4     3.4      M    M
 23000  -28.7 -19.7   280   19   10   8.1   4.5   19.0  66.1     2.8      M    M
 22000  -26.3 -15.3   280   19   10   8.1   4.5   18.4  65.1     2.3      M    M
 21000  -23.9 -11.0   285   19   10   8.1   4.4   17.9  64.2     1.9      M    M
 20000  -21.5  -6.7   290   19   10   8.1   4.4   17.2  63.0     1.3      M    M
 19500  -20.3  -4.5   290   19   10   8.1   4.4   17.0  62.5     1.1      M    M
 19000  -19.1  -2.4   295   19   10   8.1   4.4   16.7  62.1     0.9      M    M
 18500  -17.9  -0.2   295   19   10   8.4   4.6   16.5  61.7     0.7      M    M
 18000  -16.6   2.1   300   19   10   8.6   4.7   16.3  61.3     0.5      M    M
 17500  -15.3   4.5   300   20   10   8.6   4.7   16.1  61.0     0.3      M    M
 17000  -14.1   6.6   300   20   10   8.6   4.7   15.9  60.6     0.1      M    M
 16500  -12.8   9.0   300   20   10   8.6   4.7   15.7  60.3    -0.1    891  4.5
 16000  -11.5  11.3   300   20   10   8.8   4.8   15.5  60.0    -0.2    838  4.3
 15500  -10.2  13.6   300   20   10   8.8   4.8   15.4  59.7    -0.4    785  4.0
 15000   -8.9  16.0   295   20   10   9.0   4.9   15.2  59.4    -0.6    731  3.7
 14500   -7.6  18.3   290   20   10   9.1   5.0   15.1  59.2    -0.7    676  3.4
 14000   -6.3  20.7   285   20   10   9.1   5.0   15.0  59.1    -0.8    622  3.2
 13500   -4.2  24.4   275   19   10   9.2   5.1   14.9  58.8    -1.0    540  2.7
 13000   -3.0  26.6   265   19   10   7.7   4.2   14.7  58.5    -1.2    486  2.5
 12500   -1.9  28.6   260   18    9   7.1   3.9   14.3  57.8    -1.6    441  2.2
 12000   -1.0  30.2   250   18    9   5.0   2.8   13.8  56.9    -2.2    398  2.0
 11750   -0.7  30.7   245   18    9   3.8   2.1   13.4  56.1    -2.6    382  1.9
 11500   -0.4  31.3   240   18    9   3.8   2.1   12.9  55.3    -3.1    367  1.9
 11250   -0.2  31.6   240   18   10   4.9   2.7   12.5  54.5    -3.6    351  1.8
 11000    0.2  32.4   235   19   10   4.4   2.4   12.1  53.8    -3.9    333  1.7
 10750    0.4  32.7   230   19   10   2.9   1.6   11.6  52.9    -4.5    319  1.6
 10500    0.6  33.1   225   19   10   3.3   1.8   11.1  52.0    -5.0    305  1.5
 10250    0.9  33.6   220   19   10   3.3   1.8   10.6  51.1    -5.5    291  1.5
 10000    1.1  34.0   220   19   10   3.9   2.2   10.1  50.2    -6.0    276  1.4
  9750    1.4  34.5   215   19   10   4.3   2.4    9.7  49.5    -6.4    259  1.3
  9500    1.7  35.1   210   19   10   4.0   2.2    9.3  48.7    -6.9    243  1.2
  9250    2.0  35.6   205   19   10   4.5   2.5    8.8  47.9    -7.3    226  1.2
  9000    2.4  36.3   205   19   10   6.2   3.4    8.5  47.3    -7.7    207  1.1
  8750    2.9  37.2   200   19   10   6.7   3.7    8.3  46.9    -7.9    185  0.9
  8500    3.4  38.1   200   19   10   6.8   3.7    8.0  46.5    -8.2    163  0.8
  8250    3.9  39.0   195   20   10   5.8   3.2    7.8  46.1    -8.4    140  0.7
  8000    4.2  39.6   195   19   10   3.7   2.0    7.4  45.4    -8.8    123  0.6
  7750    4.5  40.1   190   18    9   5.6   3.0    7.0  44.6    -9.3    107  0.5
  7500    5.0  41.0   190   15    8   7.3   4.0    6.8  44.2    -9.5     85  0.4
  7250    5.2  41.4   190   13    6  -4.6  -2.5    6.4  43.5   -10.0     71  0.4
  7000    4.2  39.6   190    9    5 -21.7 -11.9    5.2  41.3   -11.2     95  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/22/2015 at 0900 MDT          |       04/22/2015 at 1200 MDT
                                           |
K index... +17.7  LI... +272.5             | K index... +15.3  LI... +270.0
CAPE... +74.0  CIN... -66.3                | CAPE... +577.9  CIN... -38.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -58.4 -73.1  275  37 19   0.9   0.5 | -58.6 -73.5  270  38 20   1.4   0.7
 45000 -57.1 -70.8  270  44 23   1.4   0.7 | -56.5 -69.7  270  42 22   1.8   1.0
 40000 -61.5 -78.7  245  20 10  -3.0  -1.7 | -59.4 -74.9  255  30 15  -2.0  -1.1
 38000 -61.0 -77.8  230  14  7   5.3   2.9 | -59.1 -74.4  245  24 12   3.3   1.8
 36000 -57.9 -72.2  235   9  4   5.3   2.9 | -57.1 -70.8  230  17  9   3.3   1.8
 34000 -54.6 -66.3  245   5  3   7.3   4.0 | -54.8 -66.6  210  13  7   7.6   4.2
 32000 -50.3 -58.5  265  12  6   7.1   3.9 | -50.5 -58.9  240  14  7   7.2   3.9
 30000 -46.0 -50.8  265  19 10   7.8   4.3 | -46.1 -51.0  255  18  9   7.8   4.3
 29000 -43.7 -46.7  265  19 10   7.7   4.2 | -43.2 -45.8  255  19 10   7.8   4.3
 28000 -40.8 -41.4  265  20 10   7.7   4.3 | -40.8 -41.4  260  21 11   7.8   4.3
 27000 -38.4 -37.1  265  21 11   7.9   4.4 | -38.5 -37.3  260  22 11   8.2   4.5
 26000 -36.1 -33.0  265  19 10   8.0   4.4 | -36.0 -32.8  260  21 11   8.3   4.5
 25000 -33.7 -28.7  265  18  9   8.0   4.4 | -33.6 -28.5  260  21 11   8.3   4.5
 24000 -31.3 -24.3  265  16  8   8.1   4.4 | -31.1 -24.0  260  21 11   8.1   4.4
 23000 -28.9 -20.0  270  16  8   8.1   4.5 | -28.7 -19.7  265  19 10   7.9   4.4
 22000 -26.5 -15.7  275  15  8   8.1   4.5 | -26.4 -15.5  265  17  9   8.0   4.4
 21000 -24.0 -11.2  275  15  8   8.4   4.6 | -24.0 -11.2  270  15  8   8.2   4.5
 20000 -21.6  -6.9  280  15  8   8.4   4.6 | -21.6  -6.9  275  15  8   8.2   4.5
 19500 -20.3  -4.5  285  15  8   8.4   4.6 | -20.3  -4.5  280  15  8   8.2   4.5
 19000 -19.1  -2.4  285  15  8   8.4   4.6 | -19.1  -2.4  280  15  8   8.2   4.5
 18500 -17.8  -0.0  290  15  8   8.6   4.7 | -17.9  -0.2  285  15  8   8.7   4.8
 18000 -16.5   2.3  290  15  8   8.7   4.8 | -16.6   2.1  285  14  7   8.8   4.8
 17500 -15.2   4.6  290  15  8   8.7   4.8 | -15.3   4.5  290  14  7   8.8   4.8
 17000 -14.0   6.8  295  15  8   8.5   4.7 | -14.0   6.8  290  13  7   8.6   4.7
 16500 -12.7   9.1  295  16  8   8.5   4.7 | -12.7   9.1  290  13  7   8.6   4.7
 16000 -11.4  11.5  295  16  8   8.8   4.8 | -11.4  11.5  295  12  6   9.0   4.9
 15500 -10.1  13.8  295  16  8   8.8   4.8 | -10.0  14.0  295  12  6   9.0   5.0
 15000  -8.8  16.2  295  16  8   9.1   5.0 |  -8.7  16.3  295  11  6   9.1   5.0
 14500  -7.5  18.5  295  16  8   9.3   5.1 |  -6.7  19.9  300  11  6   9.2   5.0
 14000  -5.4  22.3  295  16  8   9.5   5.2 |  -5.3  22.5  300  11  5   9.2   5.1
 13500  -4.0  24.8  295  16  8   9.5   5.2 |  -3.9  25.0  305  10  5   9.2   5.0
 13000  -2.6  27.3  290  16  8   9.2   5.1 |  -2.5  27.5  305  10  5   9.5   5.2
 12500  -1.3  29.7  285  15  8   9.2   5.1 |  -1.1  30.0  305  10  5   9.5   5.2
 12000   0.1  32.2  285  15  8   8.1   4.4 |   0.2  32.4  305  10  5   9.0   5.0
 11750   0.6  33.1  280  15  8   6.6   3.6 |   0.9  33.6  305  10  5   9.2   5.0
 11500   1.1  34.0  275  15  8   6.5   3.6 |   1.6  34.9  300  10  5   9.0   4.9
 11250   1.6  34.9  270  15  8   8.5   4.7 |   2.2  36.0  300  10  5   9.7   5.3
 11000   2.3  36.1  265  15  8   7.1   3.9 |   2.9  37.2  300  10  5   8.6   4.7
 10750   2.6  36.7  260  16  8   3.9   2.2 |   3.4  38.1  290  10  5   6.9   3.8
 10500   2.9  37.2  255  17  9   4.9   2.7 |   3.9  39.0  285   9  5   8.1   4.5
 10250   3.2  37.8  250  18  9   4.2   2.3 |   4.4  39.9  275   9  5   5.4   3.0
 10000   3.5  38.3  245  18  9   2.5   1.4 |   4.6  40.3  265   9  5   4.0   2.2
  9750   3.6  38.5  240  19 10   2.2   1.2 |   5.0  41.0  250   9  5   7.1   3.9
  9500   3.8  38.8  235  19 10   2.7   1.5 |   5.6  42.1  235   9  4   7.9   4.3
  9250   4.0  39.2  235  20 10   2.8   1.5 |   6.1  43.0  225   9  5   7.4   4.1
  9000   4.2  39.6  230  20 10   3.2   1.7 |   6.6  43.9  215  10  5   6.8   3.7
  8750   4.4  39.9  225  20 10   3.9   2.1 |   7.1  44.8  210  10  5   8.8   4.8
  8500   4.7  40.5  220  19 10   3.9   2.1 |   7.9  46.2  205  10  5  10.3   5.6
  8250   4.9  40.8  215  19 10   5.0   2.7 |   8.6  47.5  200  10  5  10.3   5.7
  8000   5.4  41.7  215  17  9   6.3   3.5 |   9.4  48.9  200  10  5  11.6   6.4
  7750   5.8  42.4  210  16  8   7.2   3.9 |  10.3  50.5  200  10  5  10.2   5.6
  7500   6.4  43.5  205  14  7   8.4   4.6 |  10.9  51.6  195  10  5   8.4   4.6
  7250   7.0  44.6  200  13  7   8.9   4.9 |  11.6  52.9  195  10  5  12.3   6.8
  7000   7.7  45.9  200  13  6   9.9   5.4 |  12.8  55.0  195  10  5  18.3  10.1
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/22/2015 at 1500 MDT          |       04/22/2015 at 1800 MDT
                                           |
K index... +22.1  LI... +270.0             | K index... +20.9  LI... +271.7
CAPE... +635.8  CIN... -9.7                | CAPE... +199.2  CIN... -7.5
                                           |
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 -58.9 -74.0  265  40 20   1.4   0.8 | -59.1 -74.4  265  41 21   1.6   0.9
 45000 -56.6 -69.9  265  41 21   0.0   0.0 | -56.5 -69.7  260  45 23  -0.1  -0.0
 40000 -58.6 -73.5  260  40 20  -1.3  -0.7 | -59.2 -74.6  260  46 24  -1.8  -1.0
 38000 -58.5 -73.3  260  37 19   2.0   1.1 | -59.1 -74.4  260  43 22   2.2   1.2
 36000 -57.3 -71.1  260  33 17   2.0   1.1 | -57.7 -71.9  255  37 19   2.2   1.2
 34000 -55.5 -67.9  260  30 16   8.7   4.8 | -55.7 -68.3  250  31 16   9.8   5.4
 32000 -50.7 -59.3  255  31 16   8.0   4.4 | -49.5 -57.1  255  27 14   9.2   5.0
 30000 -45.1 -49.2  255  31 16   9.0   5.0 | -44.0 -47.2  255  23 12   9.2   5.1
 29000 -42.4 -44.3  260  30 15   9.1   5.0 | -41.2 -42.2  260  21 11   9.2   5.1
 28000 -39.7 -39.5  265  29 15   9.1   5.0 | -38.5 -37.3  265  18  9   9.2   5.1
 27000 -37.0 -34.6  270  28 14   8.6   4.7 | -35.8 -32.4  270  16  8   8.4   4.6
 26000 -34.4 -29.9  270  27 14   8.6   4.7 | -33.3 -27.9  275  13  7   8.3   4.5
 25000 -31.9 -25.4  270  27 14   8.6   4.7 | -30.8 -23.4  280  11  5   8.3   4.5
 24000 -29.3 -20.7  275  26 13   8.1   4.4 | -28.4 -19.1  295   8  4   7.9   4.3
 23000 -27.0 -16.6  275  22 11   7.7   4.2 | -26.1 -15.0  305   6  3   7.4   4.1
 22000 -24.7 -12.5  275  18 10   7.7   4.2 | -23.9 -11.0  335   4  2   7.5   4.1
 21000 -22.5  -8.5  275  15  8   7.4   4.1 | -21.7  -7.1  010   3  2   7.2   3.9
 20000 -20.3  -4.5  275  13  7   7.4   4.0 | -19.6  -3.3  040   3  1   7.2   3.9
 19500 -19.2  -2.6  280  12  6   7.4   4.1 | -18.6  -1.5  065   2  1   7.2   3.9
 19000 -18.1  -0.6  285  11  6   7.4   4.1 | -17.5   0.5  085   3  1   7.2   3.9
 18500 -17.0   1.4  285  10  5   7.8   4.3 | -16.4   2.5  100   3  2   6.7   3.7
 18000 -15.8   3.6  290   9  5   8.0   4.4 | -15.5   4.1  130   4  2   6.4   3.5
 17500 -14.6   5.7  295   8  4   8.0   4.4 | -14.6   5.7  150   5  3   6.4   3.5
 17000 -13.5   7.7  300   7  4   7.7   4.2 | -13.6   7.5  160   6  3   7.0   3.8
 16500 -12.3   9.9  305   6  3   7.7   4.2 | -12.5   9.5  165   8  4   7.0   3.8
 16000 -11.2  11.8  315   5  3   8.0   4.4 | -11.5  11.3  170   9  5   7.2   4.0
 15500 -10.0  14.0  320   4  2   8.1   4.4 |  -9.9  14.2  175  10  5   7.2   3.9
 15000  -8.2  17.2  325   3  2   8.4   4.6 |  -8.8  16.2  175  11  6   7.8   4.3
 14500  -7.0  19.4  330   3  1   8.4   4.6 |  -7.6  18.3  175  11  6   7.7   4.2
 14000  -5.7  21.7  340   2  1   8.4   4.6 |  -6.5  20.3  175  11  6   8.3   4.6
 13500  -4.5  23.9  340   2  1   8.3   4.6 |  -5.2  22.6  180  12  6   8.4   4.6
 13000  -3.2  26.2  340   1  1   8.7   4.8 |  -4.0  24.8  180  12  6   8.1   4.5
 12500  -1.9  28.6  325   1  0   8.8   4.8 |  -2.8  27.0  185  12  6   8.0   4.4
 12000  -0.6  30.9  225   1  0   9.1   5.0 |  -1.6  29.1  185  12  6   8.2   4.5
 11750   0.1  32.2  200   1  1   9.6   5.3 |  -1.1  30.0  190  12  6   8.3   4.5
 11500   0.7  33.3  190   2  1   9.0   4.9 |  -0.5  31.1  190  12  6   7.9   4.3
 11250   1.4  34.5  185   3  1  11.1   6.1 |   0.1  32.2  190  12  6   9.5   5.2
 11000   2.3  36.1  190   3  1  10.5   5.8 |   0.9  33.6  195  12  6  10.2   5.6
 10750   2.9  37.2  185   4  2   7.8   4.3 |   1.5  34.7  195  12  6   9.1   5.0
 10500   3.5  38.3  180   6  3   9.2   5.0 |   2.2  36.0  200  12  6   9.5   5.2
 10250   4.1  39.4  180   7  4   6.6   3.6 |   2.9  37.2  200  12  6   9.1   5.0
 10000   4.5  40.1  180   9  5   5.8   3.2 |   3.6  38.5  200  12  6   8.9   4.9
  9750   5.0  41.0  180  10  5   9.0   5.0 |   4.2  39.6  205  12  6   9.2   5.1
  9500   5.7  42.3  180  10  5   9.7   5.3 |   4.9  40.8  205  12  6   9.5   5.2
  9250   6.4  43.5  180  11  6   9.6   5.2 |   5.6  42.1  210  12  6   9.2   5.0
  9000   7.1  44.8  180  11  6   9.7   5.3 |   6.3  43.3  210  12  6   8.6   4.7
  8750   7.8  46.0  180  12  6  10.3   5.7 |   6.9  44.4  215  12  6   9.3   5.1
  8500   8.6  47.5  175  12  6  10.7   5.9 |   7.6  45.7  215  12  6  10.0   5.5
  8250   9.4  48.9  175  12  6  10.6   5.8 |   8.3  46.9  220  12  6   9.8   5.4
  8000  10.2  50.4  175  12  6  10.9   6.0 |   9.0  48.2  220  11  6  10.1   5.5
  7750  11.0  51.8  175  12  6  10.1   5.5 |   9.8  49.6  220  11  6   9.0   4.9
  7500  11.7  53.1  175  12  6   8.4   4.6 |  10.4  50.7  225  11  5   7.9   4.3
  7250  12.3  54.1  175  12  6  12.1   6.6 |  10.9  51.6  225  10  5   7.0   3.8
  7000  13.5  56.3  175  11  6  19.1  10.5 |  11.3  52.3  220  10  5   4.9   2.7
  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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