Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 231135
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0535 MDT Saturday, July 23, 2016

This forecast is for Saturday, July 23, 2016:

If the trigger temperature of 78.6 F/25.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1283 ft/min (6.5 m/s)
   Maximum height of thermals.................. 18234 ft MSL (11476 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 0945 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14423 ft MSL (7665 ft AGL)
Thermal soaring outlook for Sunday 07/24....... Good

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

Remarks...

Sunrise/Sunset.................... 05:52:39 / 20:18:34 MDT
Total possible sunshine........... 14 hr 25 min 55 sec (865 min 55 sec)
Altitude of sun at 13:05:28 MDT... 70.88 degrees

Upper air data from numerical model forecast valid on 07/23/2016 at 0600 MDT

Freezing level.................. 16886 ft MSL (10128 ft AGL)
Convective condensation level... 16563 ft MSL (9805 ft AGL)
Lifted condensation level....... 16927 ft MSL (10170 ft AGL)
Lifted index.................... -2.9
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  -65.9 -86.6   255   22   11   1.5   0.8      M     M       M      M    M
 45000  -61.1 -78.0   255   28   14   6.0   3.3      M     M       M      M    M
 40000  -51.5 -60.7   250   27   14   8.0   4.4      M     M       M      M    M
 38000  -46.7 -52.1   250   27   14   8.0   4.4      M     M       M      M    M
 36000  -41.9 -43.4   250   28   14   8.1   4.5      M     M       M      M    M
 34000  -36.3 -33.3   250   27   14   8.2   4.5      M     M       M      M    M
 32000  -31.4 -24.5   250   27   14   8.5   4.7   44.9 112.9    10.9      M    M
 30000  -26.8 -16.2   250   24   13   7.7   4.2   43.1 109.6     9.7      M    M
 29000  -24.5 -12.1   250   23   12   7.7   4.2   42.4 108.4     9.2      M    M
 28000  -22.3  -8.1   245   22   11   6.8   3.7   41.6 106.8     8.6      M    M
 27000  -20.3  -4.5   245   21   11   6.9   3.8   40.4 104.7     7.8      M    M
 26000  -18.3  -0.9   245   20   10   6.9   3.8   39.4 102.9     7.0      M    M
 25000  -16.3   2.7   245   19   10   6.6   3.6   38.4 101.2     6.2      M    M
 24000  -14.3   6.3   250   17    9   6.5   3.6   37.1  98.8     5.2      M    M
 23000  -12.4   9.7   255   15    8   6.5   3.6   36.0  96.7     4.2      M    M
 22000  -10.5  13.1   260   13    7   6.9   3.8   34.9  94.8     3.4      M    M
 21000   -8.4  16.9   270   11    6   7.0   3.8   33.9  93.0     2.5      M    M
 20000   -6.3  20.7   285   10    5   7.0   3.8   33.0  91.3     1.7      M    M
 19500   -5.2  22.6   295   10    5   6.9   3.8   32.5  90.6     1.4      M    M
 19000   -4.3  24.3   300   10    5   6.5   3.6   32.0  89.6     0.9      M    M
 18500   -3.3  26.1   305   11    5   6.6   3.6   31.5  88.6     0.4      M    M
 18000   -2.4  27.7   305   11    6   6.7   3.7   30.9  87.7    -0.1   1072  5.4
 17500   -1.4  29.5   300   11    6   6.8   3.7   30.4  86.8    -0.7   1028  5.2
 17000   -0.5  31.1   295   11    6   7.0   3.8   29.9  85.9    -1.2    985  5.0
 16500    0.6  33.1   290   11    6   7.9   4.3   29.6  85.2    -1.6    939  4.8
 16000    2.2  36.0   280   11    5   8.1   4.5   29.1  84.4    -2.2    868  4.4
 15500    3.4  38.1   280   10    5   8.6   4.7   28.9  84.0    -2.5    818  4.2
 15000    4.6  40.3   285    9    4   8.7   4.8   28.7  83.7    -2.8    766  3.9
 14500    5.8  42.4   295    8    4   8.4   4.6   28.5  83.3    -3.0    715  3.6
 14000    7.1  44.8   305    7    4   8.5   4.7   28.3  83.0    -3.2    663  3.4
 13500    8.3  46.9   315    7    3   8.3   4.5   28.1  82.6    -3.5    611  3.1
 13000    9.6  49.3   325    7    4   8.1   4.4   27.9  82.1    -3.7    559  2.8
 12500   10.9  51.6   330    7    4   9.1   5.0   27.7  81.9    -3.9    505  2.6
 12000   12.1  53.8   335    8    4   8.6   4.7   27.5  81.5    -4.1    451  2.3
 11750   12.8  55.0   340    9    5   8.1   4.4   27.4  81.4    -4.2    425  2.2
 11500   13.4  56.1   340    9    5   9.9   5.4   27.3  81.2    -4.3    398  2.0
 11250   14.2  57.6   345   10    5   9.4   5.2   27.4  81.3    -4.2    367  1.9
 11000   14.8  58.6   345   10    5   7.4   4.1   27.2  81.0    -4.4    342  1.7
 10750   15.4  59.7   345   11    6   7.8   4.3   27.1  80.8    -4.5    317  1.6
 10500   16.0  60.8   345   12    6   8.3   4.6   26.9  80.5    -4.7    292  1.5
 10250   16.6  61.9   345   12    6   9.1   5.0   26.9  80.4    -4.8    265  1.3
 10000   17.3  63.1   345   13    7   8.6   4.7   26.8  80.3    -4.9    238  1.2
  9750   17.9  64.2   345   14    7   8.3   4.6   26.7  80.1    -5.0    212  1.1
  9500   18.5  65.3   345   15    8   8.5   4.7   26.6  79.9    -5.1    186  0.9
  9250   19.2  66.6   345   15    8   8.7   4.8   26.5  79.7    -5.2    160  0.8
  9000   19.8  67.6   345   16    8   8.4   4.6   26.4  79.6    -5.3    133  0.7
  8750   20.4  68.7   345   17    9   8.2   4.5   26.3  79.4    -5.4    107  0.5
  8500   20.9  69.6   340   17    9   5.9   3.2   26.2  79.1    -5.7     84  0.4
  8250   21.2  70.2   340   17    9   1.9   1.1   25.7  78.2    -6.2     69  0.4
  8000   21.4  70.5   335   17    9   8.8   4.8   25.2  77.4    -6.7     55  0.3
  7750   21.7  71.1   330   17    9 -14.8  -8.1   24.8  76.6    -7.2     40  0.2
  7500   19.3  66.7   325   17    9 -26.2 -14.3   22.0  71.5   -10.2    104  0.5
  7250   18.3  64.9   320   14    7  -6.9  -3.8   20.6  69.1   -11.5    126  0.6
  7000   17.3  63.1   315   11    6 -23.4 -12.8   19.3  66.8   -12.9    149  0.8
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/23/2016 at 0900 MDT          |       07/23/2016 at 1200 MDT
                                           |
K index... +24.5  LI... +272.0             | K index... +28.2  LI... +271.6
CAPE... +190.7  CIN... -51.6               | CAPE... +178.2  CIN... -10.9
                                           |
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 -65.3 -85.5  250  20 10   1.7   0.9 | -65.4 -85.7  250  19 10   0.9   0.5
 45000 -60.4 -76.7  245  27 14   5.9   3.3 | -61.0 -77.8  245  29 15   6.4   3.5
 40000 -50.6 -59.1  245  30 15   7.5   4.1 | -50.5 -58.9  245  34 17   7.7   4.3
 38000 -46.1 -51.0  250  29 15   7.5   4.1 | -45.9 -50.6  245  32 17   7.7   4.3
 36000 -41.6 -42.9  250  29 15   8.1   4.5 | -41.3 -42.3  250  30 16   7.9   4.4
 34000 -36.6 -33.9  255  28 15   8.3   4.5 | -36.5 -33.7  255  29 15   8.0   4.4
 32000 -31.7 -25.1  255  28 15   8.7   4.8 | -31.7 -25.1  260  27 14   8.6   4.7
 30000 -27.2 -17.0  255  26 14   7.5   4.1 | -27.1 -16.8  260  26 13   7.8   4.3
 29000 -24.9 -12.8  250  25 13   7.5   4.1 | -24.8 -12.6  260  25 13   7.8   4.3
 28000 -22.8  -9.0  250  24 13   6.3   3.4 | -22.1  -7.8  260  23 12   6.4   3.5
 27000 -20.5  -4.9  250  22 11   6.3   3.5 | -20.3  -4.5  260  21 11   6.3   3.5
 26000 -18.6  -1.5  250  20 11   6.3   3.5 | -18.4  -1.1  265  19 10   6.4   3.5
 25000 -16.8   1.8  250  19 10   6.6   3.6 | -16.5   2.3  265  17  9   6.4   3.5
 24000 -14.8   5.4  250  18  9   6.6   3.6 | -14.6   5.7  265  16  8   6.4   3.5
 23000 -12.9   8.8  250  16  8   6.6   3.6 | -12.7   9.1  260  16  8   6.4   3.5
 22000 -10.9  12.4  250  15  8   7.4   4.1 | -10.8  12.6  260  15  8   6.9   3.8
 21000  -8.7  16.3  255  11  6   7.5   4.1 |  -8.8  16.2  265  12  6   7.0   3.8
 20000  -6.4  20.5  265   8  4   7.5   4.1 |  -6.7  19.9  265   9  5   7.0   3.8
 19500  -5.3  22.5  275   7  4   7.2   4.0 |  -5.7  21.7  265   8  4   6.9   3.8
 19000  -4.3  24.3  285   6  3   6.8   3.7 |  -4.7  23.5  275   6  3   6.7   3.7
 18500  -3.3  26.1  305   6  3   6.8   3.7 |  -3.7  25.3  290   5  3   6.7   3.7
 18000  -2.3  27.9  315   6  3   7.2   3.9 |  -2.8  27.0  305   4  2   7.2   4.0
 17500  -1.3  29.7  320   6  3   7.2   4.0 |  -1.7  28.9  315   4  2   7.3   4.0
 17000  -0.2  31.6  325   6  3   7.3   4.0 |  -0.7  30.7  325   4  2   7.4   4.0
 16500   0.8  33.4  325   6  3   7.6   4.2 |   0.3  32.5  330   3  2   7.4   4.0
 16000   1.9  35.4  325   6  3   7.6   4.2 |   1.4  34.5  340   3  2   7.3   4.0
 15500   3.0  37.4  325   6  3   8.2   4.5 |   2.5  36.5  350   3  2   8.5   4.7
 15000   4.1  39.4  325   6  3   8.2   4.5 |   3.7  38.7  010   3  2   8.5   4.6
 14500   5.3  41.5  325   5  3   8.4   4.6 |   4.9  40.8  025   3  2   8.7   4.8
 14000   7.1  44.8  340   5  3   8.5   4.6 |   6.8  44.2  040   5  2   8.8   4.8
 13500   8.3  46.9  355   6  3   8.8   4.8 |   8.1  46.6  040   6  3   9.5   5.2
 13000   9.6  49.3  360   7  4   8.9   4.9 |   9.5  49.1  035   6  3   9.5   5.2
 12500  10.9  51.6  010   8  4   8.5   4.7 |  10.9  51.6  035   7  3   9.2   5.1
 12000  12.2  54.0  015   9  5   8.7   4.8 |  12.3  54.1  030   7  4   9.7   5.3
 11750  12.8  55.0  020  10  5   8.7   4.8 |  13.0  55.4  030   7  4   9.9   5.4
 11500  13.5  56.3  020  10  5   9.5   5.2 |  13.8  56.8  030   7  4  11.4   6.2
 11250  14.2  57.6  020  11  5   9.0   4.9 |  14.6  58.3  030   7  4  10.6   5.8
 11000  14.8  58.6  020  11  5   8.0   4.4 |  15.4  59.7  030   7  4   9.0   5.0
 10750  15.4  59.7  020  11  6   8.1   4.5 |  16.1  61.0  030   7  4   9.4   5.2
 10500  16.0  60.8  020  11  6   9.0   4.9 |  16.8  62.2  030   7  4  10.0   5.5
 10250  16.7  62.1  015  11  6   9.8   5.4 |  17.5  63.5  030   7  4  10.4   5.7
 10000  17.4  63.3  015  11  6   8.3   4.6 |  18.3  64.9  025   7  4   9.7   5.3
  9750  17.9  64.2  010  11  6   7.5   4.1 |  19.0  66.2  025   7  4   9.3   5.1
  9500  18.5  65.3  005  11  6   7.9   4.3 |  19.7  67.5  025   7  4   9.5   5.2
  9250  19.1  66.4  360  12  6   7.9   4.3 |  20.4  68.7  025   7  4   9.4   5.1
  9000  19.8  67.6  355  13  7   8.2   4.5 |  21.1  70.0  025   7  4   9.8   5.4
  8750  20.4  68.7  350  14  7   9.1   5.0 |  21.9  71.4  025   7  4  10.9   6.0
  8500  21.1  70.0  350  15  8   9.0   4.9 |  22.7  72.9  025   7  3  10.7   5.9
  8250  21.7  71.1  345  15  7   8.8   4.8 |  23.4  74.1  025   7  3  10.4   5.7
  8000  22.3  72.1  345  14  7   8.3   4.6 |  24.2  75.6  025   7  3  10.0   5.5
  7750  22.9  73.2  340  14  7  10.7   5.9 |  25.0  77.0  025   6  3  11.9   6.5
  7500  23.7  74.7  335  13  7   9.8   5.4 |  26.0  78.8  025   6  3  12.9   7.1
  7250  24.1  75.4  335  12  6   6.0   3.3 |  26.8  80.2  025   6  3  11.4   6.3
  7000  24.6  76.3  335  10  5   9.2   5.0 |  27.6  81.7  030   6  3  12.8   7.0
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/23/2016 at 1500 MDT          |       07/23/2016 at 1800 MDT
                                           |
K index... +29.3  LI... +271.3             | K index... +30.1  LI... +270.9
CAPE... +241.6  CIN... -3.7                | CAPE... +234.6  CIN... -6.9
                                           |
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 -65.4 -85.7  240  20 10   0.6   0.3 | -65.5 -85.9  240  19 10   1.0   0.6
 45000 -61.3 -78.3  245  34 18   6.5   3.6 | -61.2 -78.2  250  31 16   6.1   3.4
 40000 -50.6 -59.1  245  41 21   8.0   4.4 | -50.9 -59.6  250  41 21   8.2   4.5
 38000 -45.8 -50.4  245  39 20   8.0   4.4 | -46.0 -50.8  250  39 20   8.2   4.5
 36000 -41.0 -41.8  245  37 19   7.8   4.3 | -41.1 -42.0  250  36 19   8.4   4.6
 34000 -36.3 -33.3  250  34 17   7.8   4.3 | -36.1 -33.0  255  32 16   8.4   4.6
 32000 -31.6 -24.9  255  31 16   8.7   4.8 | -31.0 -23.8  255  27 14   9.0   4.9
 30000 -27.0 -16.6  250  27 14   7.7   4.2 | -26.6 -15.9  255  22 11   7.4   4.1
 29000 -24.8 -12.6  250  24 13   7.8   4.3 | -24.4 -11.9  255  19 10   7.4   4.1
 28000 -22.1  -7.8  250  22 11   6.6   3.6 | -21.8  -7.2  260  16  8   6.8   3.7
 27000 -20.1  -4.2  255  20 10   6.6   3.6 | -19.8  -3.6  270  16  8   6.8   3.8
 26000 -18.1  -0.6  260  18  9   6.6   3.6 | -17.8  -0.0  275  15  8   6.9   3.8
 25000 -16.2   2.8  270  16  8   6.6   3.6 | -15.8   3.6  285  15  8   6.4   3.5
 24000 -14.3   6.3  275  16  8   6.6   3.6 | -13.9   7.0  285  14  7   6.4   3.5
 23000 -12.3   9.9  280  16  8   6.6   3.6 | -12.1  10.2  285  13  7   6.4   3.5
 22000 -10.4  13.3  285  16  8   6.4   3.5 | -10.2  13.6  290  12  6   6.0   3.3
 21000  -8.5  16.7  290  15  7   6.4   3.5 |  -8.5  16.7  295   8  4   6.0   3.3
 20000  -6.6  20.1  300  13  7   6.4   3.5 |  -6.7  19.9  310   4  2   6.0   3.3
 19500  -5.7  21.7  305  13  7   6.5   3.5 |  -5.8  21.6  330   3  1   6.3   3.4
 19000  -4.7  23.5  310  12  6   6.5   3.6 |  -4.9  23.2  045   2  1   6.8   3.7
 18500  -3.8  25.2  315  11  6   6.5   3.5 |  -3.9  25.0  090   4  2   6.7   3.7
 18000  -2.8  27.0  325  10  5   7.0   3.8 |  -2.9  26.8  100   6  3   7.5   4.1
 17500  -1.8  28.8  340   8  4   7.1   3.9 |  -1.8  28.8  100   7  3   7.6   4.2
 17000  -0.9  30.4  360   6  3   7.4   4.1 |  -0.7  30.7  105   7  4   7.8   4.3
 16500   0.3  32.5  020   6  3   8.2   4.5 |   0.5  32.9  105   7  4   8.3   4.5
 16000   1.4  34.5  040   6  3   8.1   4.5 |   1.6  34.9  105   7  4   8.1   4.5
 15500   2.6  36.7  055   6  3   9.6   5.3 |   2.9  37.2  105   7  4   9.6   5.3
 15000   4.0  39.2  055   6  3   9.5   5.2 |   4.3  39.7  105   7  4   9.6   5.3
 14500   5.4  41.7  060   6  3   9.9   5.4 |   5.8  42.4  105   7  4   9.8   5.4
 14000   7.6  45.7  060   6  3  10.1   5.5 |   8.0  46.4  110   7  4   9.9   5.4
 13500   9.1  48.4  065   5  3   9.6   5.3 |   9.4  48.9  110   7  4   9.9   5.4
 13000  10.5  50.9  065   5  3   9.6   5.2 |  10.9  51.6  110   7  4  10.1   5.5
 12500  11.9  53.4  065   5  3   9.9   5.4 |  12.3  54.1  110   7  4   8.9   4.9
 12000  13.4  56.1  070   5  3   9.8   5.4 |  13.7  56.7  115   7  3   9.5   5.2
 11750  14.1  57.4  070   5  3   9.9   5.4 |  14.4  57.9  115   7  3   9.4   5.1
 11500  14.9  58.8  070   5  3  11.0   6.0 |  15.1  59.2  115   7  3  10.6   5.8
 11250  15.7  60.3  070   5  3  10.2   5.6 |  15.9  60.6  115   7  3  10.1   5.6
 11000  16.4  61.5  070   5  3   9.0   5.0 |  16.6  61.9  120   6  3   8.8   4.8
 10750  17.1  62.8  075   5  3   9.2   5.0 |  17.2  63.0  120   6  3   9.1   5.0
 10500  17.8  64.0  075   5  3  10.3   5.6 |  17.9  64.2  120   6  3   9.2   5.0
 10250  18.6  65.5  075   5  3  11.1   6.1 |  18.6  65.5  125   6  3   9.4   5.1
 10000  19.4  66.9  075   5  3   9.7   5.3 |  19.3  66.7  125   6  3   9.5   5.2
  9750  20.1  68.2  080   5  3   9.1   5.0 |  20.0  68.0  130   6  3   9.8   5.4
  9500  20.8  69.4  080   5  2   9.6   5.3 |  20.7  69.3  130   6  3   9.4   5.1
  9250  21.5  70.7  080   5  2   9.9   5.4 |  21.4  70.5  135   6  3   8.8   4.8
  9000  22.2  72.0  080   5  2  10.0   5.5 |  22.0  71.6  135   6  3   9.4   5.2
  8750  23.0  73.4  080   5  2  10.4   5.7 |  22.8  73.0  140   6  3  10.6   5.8
  8500  23.8  74.8  080   5  2  10.4   5.7 |  23.6  74.5  140   6  3  10.3   5.7
  8250  24.5  76.1  085   5  2  10.3   5.7 |  24.3  75.7  140   6  3   9.8   5.4
  8000  25.3  77.5  085   5  2  10.1   5.6 |  25.0  77.0  145   6  3   9.8   5.4
  7750  26.1  79.0  090   4  2  10.9   6.0 |  25.8  78.4  145   6  3  10.3   5.7
  7500  26.9  80.4  090   4  2  12.1   6.6 |  26.5  79.7  145   6  3   8.3   4.6
  7250  27.8  82.0  085   4  2  12.1   6.6 |  26.9  80.4  145   5  3   5.7   3.1
  7000  28.6  83.5  085   5  2  12.2   6.7 |  27.3  81.1  140   5  3   7.8   4.3
  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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