Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 281234
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0634 MDT Tuesday, July 28, 2015

This forecast is for Tuesday, July 28, 2015:

If the trigger temperature of 76.1 F/24.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 347 ft/min (1.8 m/s)
   Maximum height of thermals.................. 13028 ft MSL (6270 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1300 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................. 9762 ft MSL (3005 ft AGL)
Thermal soaring outlook for Wednesday 07/29.... Good

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

Remarks...

Sunrise/Sunset.................... 05:56:14 / 20:15:01 MDT
Total possible sunshine........... 14 hr 18 min 47 sec (858 min 47 sec)
Altitude of sun at 13:05:26 MDT... 69.95 degrees

Upper air data from numerical model forecast valid on 07/28/2015 at 0600 MDT

Freezing level.................. 16139 ft MSL (9381 ft AGL)
Convective condensation level... 19737 ft MSL (12979 ft AGL)
Lifted condensation level....... 17712 ft MSL (10955 ft AGL)
Lifted index.................... +2.9
K index......................... +19.2

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  -65.3 -85.5   235   33   17   2.4   1.3      M     M       M      M    M
 45000  -60.2 -76.4   235   42   22   5.5   3.0      M     M       M      M    M
 40000  -51.2 -60.2   235   49   25   7.0   3.8      M     M       M      M    M
 38000  -47.0 -52.6   235   49   25   7.0   3.8      M     M       M      M    M
 36000  -42.9 -45.2   230   49   25   7.1   3.9      M     M       M      M    M
 34000  -38.4 -37.1   235   46   24   7.5   4.1      M     M       M      M    M
 32000  -33.9 -29.0   235   43   22   7.4   4.1      M     M       M      M    M
 30000  -29.2 -20.6   240   38   20   7.8   4.3   41.0 105.9    11.6      M    M
 29000  -26.9 -16.4   240   36   18   7.8   4.3   40.3 104.6    11.2      M    M
 28000  -24.6 -12.3   240   33   17   7.7   4.2   39.7 103.5    10.8      M    M
 27000  -21.7  -7.1   240   31   16   7.6   4.2   38.6 101.5    10.1      M    M
 26000  -19.4  -2.9   240   29   15   7.6   4.2   37.8 100.1     9.6      M    M
 25000  -17.2   1.0   240   27   14   7.5   4.1   37.2  98.9     9.1      M    M
 24000  -14.9   5.2   240   26   13   7.5   4.1   36.2  97.2     8.5      M    M
 23000  -12.7   9.1   240   25   13   7.5   4.1   35.4  95.8     7.9      M    M
 22000  -10.5  13.1   240   24   12   6.0   3.3   34.7  94.5     7.3      M    M
 21000   -9.1  15.6   230   24   12   4.9   2.7   32.9  91.2     5.8      M    M
 20000   -7.7  18.1   225   24   12   5.2   2.8   31.3  88.3     4.4      M    M
 19500   -6.9  19.6   220   24   13   5.4   3.0   30.6  87.0     3.7      M    M
 19000   -6.2  20.8   220   25   13   5.8   3.2   29.9  85.7     3.0      M    M
 18500   -5.4  22.3   215   25   13   6.1   3.3   29.2  84.6     2.3      M    M
 18000   -4.7  23.5   215   25   13   7.2   3.9   28.6  83.5     1.6      M    M
 17500   -3.5  25.7   215   24   12   8.0   4.4   28.3  82.9     1.3      M    M
 17000   -2.4  27.7   215   24   12   8.1   4.4   28.0  82.5     1.0      M    M
 16500   -1.1  30.0   215   23   12   8.7   4.8   27.8  82.1     0.8      M    M
 16000    0.1  32.2   215   23   12   8.6   4.7   27.6  81.7     0.6      M    M
 15500    1.4  34.5   220   22   12   9.0   4.9   27.5  81.4     0.5      M    M
 15000    2.8  37.0   220   22   11   9.1   5.0   27.4  81.2     0.4      M    M
 14500    4.2  39.6   225   22   11   9.1   5.0   27.3  81.1     0.4      M    M
 14000    5.6  42.1   230   21   11   8.9   4.9   27.1  80.8     0.3      M    M
 13500    7.7  45.9   235   20   10   8.2   4.5   26.9  80.5     0.2      M    M
 13000    8.9  48.0   245   20   10   7.9   4.3   26.6  79.9    -0.1    534  2.7
 12500   10.1  50.2   255   20   10   8.0   4.4   26.3  79.4    -0.3    483  2.5
 12000   11.3  52.3   265   20   10   8.3   4.6   26.1  78.9    -0.6    432  2.2
 11750   11.9  53.4   265   19   10   8.3   4.6   26.0  78.7    -0.7    407  2.1
 11500   12.5  54.5   270   19   10   8.3   4.5   25.9  78.6    -0.9    382  1.9
 11250   13.0  55.4   270   18    9   6.9   3.8   25.7  78.3    -1.0    358  1.8
 11000   13.5  56.3   275   17    9   5.9   3.3   25.4  77.8    -1.3    337  1.7
 10750   13.9  57.0   275   15    8   6.2   3.4   25.1  77.3    -1.6    317  1.6
 10500   14.3  57.7   275   14    7   5.8   3.2   24.9  76.8    -1.9    296  1.5
 10250   14.7  58.5   280   12    6   5.9   3.2   24.6  76.2    -2.2    277  1.4
 10000   15.1  59.2   285   11    6   4.0   2.2   24.2  75.6    -2.6    258  1.3
  9750   15.3  59.5   295    9    5   2.7   1.5   23.7  74.6    -3.1    245  1.2
  9500   15.5  59.9   305    8    4   2.1   1.1   23.2  73.7    -3.7    231  1.2
  9250   15.6  60.1   320    7    4   0.1   0.0   22.5  72.5    -4.4    223  1.1
  9000   15.5  59.9   340    8    4   0.1   0.1   21.7  71.1    -5.1    216  1.1
  8750   15.6  60.1   355    9    5   2.0   1.1   21.1  69.9    -5.8    207  1.1
  8500   15.7  60.3   010   11    6   1.7   0.9   20.5  68.9    -6.4    196  1.0
  8250   15.8  60.4   010   12    6   0.5   0.2   19.8  67.7    -7.1    187  1.0
  8000   15.8  60.4   015   13    7  -0.4  -0.2   19.1  66.4    -7.9    179  0.9
  7750   15.8  60.4   015   15    8   3.3   1.8   18.4  65.1    -8.6    171  0.9
  7500   16.0  60.8   015   15    8  -3.8  -2.1   17.9  64.2    -9.1    159  0.8
  7250   15.1  59.2   010   12    6 -14.8  -8.1   16.7  62.1   -10.3    178  0.9
  7000   14.2  57.6   005   10    5  -6.2  -3.4   15.5  59.9   -11.6    197  1.0
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/28/2015 at 0900 MDT          |       07/28/2015 at 1200 MDT
                                           |
K index... +1.6  LI... +276.5              | K index... +2.0  LI... +276.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.6
                                           |
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 -65.6 -86.1  230  34 17   2.4   1.3 | -65.5 -85.9  230  38 19   2.1   1.1
 45000 -60.3 -76.5  235  45 23   5.7   3.2 | -60.5 -76.9  230  53 27   6.0   3.3
 40000 -51.0 -59.8  240  55 28   6.9   3.8 | -50.8 -59.4  235  58 30   6.8   3.7
 38000 -46.9 -52.4  235  53 27   6.9   3.8 | -46.8 -52.2  235  56 29   6.8   3.7
 36000 -42.8 -45.0  235  52 27   7.0   3.8 | -42.7 -44.9  240  55 28   7.0   3.8
 34000 -38.4 -37.1  235  48 25   7.3   4.0 | -38.3 -36.9  235  52 27   7.4   4.1
 32000 -34.0 -29.2  230  45 23   7.1   3.9 | -33.9 -29.0  235  48 25   7.2   4.0
 30000 -29.2 -20.6  230  41 21   8.1   4.5 | -29.1 -20.4  235  44 22   8.0   4.4
 29000 -26.8 -16.2  230  38 20   8.1   4.5 | -26.7 -16.1  235  42 21   8.0   4.4
 28000 -23.8 -10.8  235  35 18   7.3   4.0 | -23.8 -10.8  235  39 20   7.6   4.2
 27000 -21.6  -6.9  230  32 17   7.4   4.1 | -21.5  -6.7  235  36 19   7.7   4.2
 26000 -19.4  -2.9  230  29 15   7.4   4.1 | -19.1  -2.4  235  34 17   7.7   4.2
 25000 -17.1   1.2  230  26 14   7.2   4.0 | -16.8   1.8  230  31 16   7.0   3.9
 24000 -15.0   5.0  235  25 13   7.1   3.9 | -14.9   5.2  235  27 14   6.5   3.6
 23000 -12.9   8.8  235  23 12   7.0   3.9 | -12.9   8.8  240  23 12   6.5   3.6
 22000 -10.8  12.6  235  22 11   5.8   3.2 | -11.0  12.2  245  20 10   6.4   3.5
 21000  -9.3  15.3  235  23 12   5.0   2.8 |  -9.1  15.6  245  20 10   6.3   3.4
 20000  -7.9  17.8  235  24 12   5.1   2.8 |  -7.2  19.0  250  19 10   6.3   3.4
 19500  -7.1  19.2  235  24 12   5.1   2.8 |  -6.3  20.7  250  19 10   6.2   3.4
 19000  -6.3  20.7  230  25 13   6.2   3.4 |  -5.5  22.1  250  20 10   5.0   2.7
 18500  -5.4  22.3  230  25 13   6.2   3.4 |  -4.8  23.4  250  21 11   5.1   2.8
 18000  -4.5  23.9  225  26 13   6.9   3.8 |  -4.0  24.8  250  22 11   5.6   3.1
 17500  -3.4  25.9  225  26 13   7.4   4.1 |  -3.1  26.4  250  23 12   5.9   3.2
 17000  -2.3  27.9  230  26 13   7.5   4.1 |  -2.3  27.9  250  24 12   6.0   3.3
 16500  -1.2  29.8  230  25 13   7.5   4.1 |  -1.4  29.5  255  24 13   6.9   3.8
 16000  -0.1  31.8  235  24 12   7.5   4.1 |  -0.4  31.3  255  25 13   6.9   3.8
 15500   1.0  33.8  235  23 12   8.5   4.7 |   0.6  33.1  255  25 13   8.2   4.5
 15000   2.3  36.1  240  21 11   8.8   4.8 |   1.9  35.4  250  23 12   8.5   4.7
 14500   3.7  38.7  245  20 10   8.8   4.8 |   3.1  37.6  250  21 11   8.9   4.9
 14000   5.6  42.1  245  19 10   8.9   4.9 |   5.2  41.4  250  18  9   9.4   5.2
 13500   6.9  44.4  250  18  9   8.8   4.8 |   6.5  43.7  245  16  8   9.5   5.2
 13000   8.2  46.8  250  18  9   8.9   4.9 |   8.0  46.4  245  16  8   9.6   5.2
 12500   9.5  49.1  255  18  9   9.0   4.9 |   9.3  48.7  245  15  8   8.6   4.7
 12000  10.9  51.6  250  17  9   9.3   5.1 |  10.6  51.1  235  15  8   8.4   4.6
 11750  11.6  52.9  250  17  9   9.5   5.2 |  11.2  52.2  235  15  8   9.0   4.9
 11500  12.3  54.1  250  17  9   8.9   4.9 |  11.8  53.2  230  15  8   6.6   3.6
 11250  12.9  55.2  250  17  9   8.3   4.5 |  12.1  53.8  225  15  8   4.0   2.2
 11000  13.5  56.3  250  16  8   8.4   4.6 |  12.4  54.3  220  15  8   4.3   2.4
 10750  14.1  57.4  245  16  8   8.5   4.7 |  12.7  54.9  215  15  8   4.4   2.4
 10500  14.7  58.5  245  16  8   7.8   4.3 |  13.0  55.4  210  16  8   3.7   2.0
 10250  15.2  59.4  245  15  8   7.5   4.1 |  13.1  55.6  205  15  8   2.4   1.3
 10000  15.8  60.4  250  14  7   5.5   3.0 |  13.3  55.9  200  14  7   4.3   2.4
  9750  16.0  60.8  245  13  7   4.6   2.5 |  13.7  56.7  190  13  7   5.6   3.1
  9500  16.3  61.3  245  12  6   1.9   1.1 |  14.1  57.4  185  13  7   6.3   3.4
  9250  16.2  61.2  250   9  5  -1.8  -1.0 |  14.5  58.1  180  13  7   7.3   4.0
  9000  16.1  61.0  260   7  3  -1.4  -0.7 |  15.0  59.0  175  12  6   7.6   4.2
  8750  15.9  60.6  270   4  2  -3.1  -1.7 |  15.7  60.3  170  12  6   9.9   5.4
  8500  15.6  60.1  310   2  1  -1.9  -1.0 |  16.4  61.5  170  12  6  10.8   5.9
  8250  15.5  59.9  350   3  2   0.7   0.4 |  17.2  63.0  170  12  6  10.5   5.8
  8000  15.5  59.9  005   5  2  -1.6  -0.9 |  18.0  64.4  165  12  6  10.0   5.5
  7750  15.4  59.7  015   6  3   5.2   2.8 |  18.8  65.8  165  12  6  12.3   6.8
  7500  16.1  61.0  025   7  4  10.4   5.7 |  19.8  67.6  165  12  6  13.4   7.4
  7250  16.7  62.1  025   7  4   6.7   3.7 |  20.6  69.1  165  12  6  11.4   6.3
  7000  17.2  63.0  030   7  3  10.1   5.5 |  21.5  70.7  165  11  6  13.2   7.2
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/28/2015 at 1500 MDT          |       07/28/2015 at 1800 MDT
                                           |
K index... +16.4  LI... +275.4             | K index... +21.6  LI... +273.4
CAPE... 0.0  CIN... -0.3                   | CAPE... +5.5  CIN... -8.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -65.8 -86.4  230  43 22   1.6   0.9 | -66.4 -87.5  235  44 23   1.9   1.0
 45000 -61.0 -77.8  230  60 31   6.4   3.5 | -60.9 -77.6  235  61 31   6.4   3.5
 40000 -50.7 -59.3  230  64 33   7.0   3.8 | -50.9 -59.6  225  65 33   7.6   4.2
 38000 -46.5 -51.7  230  60 31   7.0   3.8 | -46.4 -51.5  230  61 31   7.6   4.2
 36000 -42.3 -44.1  235  57 29   7.2   4.0 | -41.8 -43.2  230  57 29   7.8   4.3
 34000 -37.7 -35.9  235  54 28   7.7   4.2 | -37.0 -34.6  230  55 28   8.0   4.4
 32000 -33.1 -27.6  240  50 26   7.6   4.2 | -32.2 -26.0  235  54 28   8.8   4.8
 30000 -28.7 -19.7  240  46 24   7.4   4.1 | -28.1 -18.6  235  48 24   6.8   3.8
 29000 -25.9 -14.6  235  43 22   7.4   4.1 | -25.5 -13.9  240  44 22   6.9   3.8
 28000 -23.6 -10.5  235  40 21   7.4   4.1 | -23.4 -10.1  245  41 21   7.6   4.2
 27000 -21.4  -6.5  235  38 20   7.5   4.1 | -21.1  -6.0  245  38 20   7.5   4.1
 26000 -19.1  -2.4  235  36 19   7.5   4.1 | -18.8  -1.8  250  36 19   7.5   4.1
 25000 -16.9   1.6  235  34 17   6.8   3.7 | -16.6   2.1  255  34 18   6.4   3.5
 24000 -15.0   5.0  240  29 15   6.3   3.4 | -14.9   5.2  255  31 16   5.4   3.0
 23000 -13.2   8.2  245  25 13   6.3   3.4 | -13.3   8.1  255  29 15   5.4   3.0
 22000 -11.3  11.7  245  21 11   6.7   3.7 | -11.7  10.9  255  26 14   5.4   3.0
 21000  -9.2  15.4  250  20 11   7.0   3.8 | -10.1  13.8  260  27 14   5.5   3.0
 20000  -7.1  19.2  250  20 10   7.0   3.8 |  -8.5  16.7  270  28 14   5.7   3.1
 19500  -6.1  21.0  250  20 10   6.9   3.8 |  -7.7  18.1  270  28 14   6.0   3.3
 19000  -5.3  22.5  255  21 11   4.0   2.2 |  -6.7  19.9  270  26 13   8.1   4.5
 18500  -4.7  23.5  265  22 11   4.4   2.4 |  -5.6  21.9  270  23 12   8.1   4.5
 18000  -4.1  24.6  265  24 12   5.5   3.0 |  -4.4  24.1  265  21 11   8.7   4.8
 17500  -3.2  26.2  265  22 11   6.3   3.4 |  -3.2  26.2  265  18  9   9.0   4.9
 17000  -2.4  27.7  265  21 11   6.8   3.7 |  -1.9  28.6  260  16  8   9.0   5.0
 16500  -1.3  29.7  265  19 10   8.9   4.9 |  -0.6  30.9  260  15  8   8.6   4.7
 16000  -0.1  31.8  265  18  9   8.8   4.8 |   0.6  33.1  255  14  7   8.7   4.8
 15500   1.1  34.0  265  17  8   9.1   5.0 |   1.9  35.4  250  13  7   8.4   4.6
 15000   2.5  36.5  265  15  8   9.1   5.0 |   3.2  37.8  245  13  7   8.4   4.6
 14500   4.5  40.1  260  14  7   8.7   4.8 |   5.0  41.0  230  12  6   7.7   4.2
 14000   5.8  42.4  255  14  7   8.8   4.8 |   6.2  43.2  210  13  7   7.9   4.4
 13500   7.1  44.8  245  13  7   8.4   4.6 |   7.3  45.1  200  14  7   5.4   3.0
 13000   8.4  47.1  235  13  7   8.4   4.6 |   8.0  46.4  185  15  8   4.9   2.7
 12500   9.6  49.3  220  13  7   6.8   3.7 |   8.8  47.8  175  17  9   6.3   3.5
 12000  10.5  50.9  205  13  7   6.1   3.4 |   9.7  49.5  170  17  9   6.3   3.5
 11750  10.9  51.6  195  14  7   6.5   3.6 |  10.1  50.2  170  18  9   5.6   3.1
 11500  11.4  52.5  190  15  8   4.9   2.7 |  10.6  51.1  170  18  9   8.9   4.9
 11250  11.7  53.1  185  15  8   4.8   2.6 |  11.4  52.5  165  18  9  10.3   5.6
 11000  12.1  53.8  180  15  8   6.6   3.6 |  12.0  53.6  165  18  9   8.2   4.5
 10750  12.5  54.5  175  16  8   5.8   3.2 |  12.6  54.7  165  18  9   8.4   4.6
 10500  13.0  55.4  175  16  8   7.7   4.2 |  13.3  55.9  165  18  9   9.5   5.2
 10250  13.6  56.5  170  16  8   9.7   5.3 |  14.0  57.2  165  18  9  10.8   6.0
 10000  14.2  57.6  170  16  8   9.2   5.1 |  14.8  58.6  165  18  9   9.5   5.2
  9750  14.9  58.8  170  16  8   9.0   4.9 |  15.5  59.9  165  18  9   8.6   4.7
  9500  15.6  60.1  170  16  8   9.4   5.2 |  16.1  61.0  165  18  9   9.4   5.1
  9250  16.3  61.3  170  16  8   9.8   5.4 |  16.9  62.4  165  18  9   9.8   5.4
  9000  17.1  62.8  170  16  8   9.8   5.4 |  17.6  63.7  165  18  9   9.8   5.4
  8750  17.8  64.0  170  16  8  10.1   5.6 |  18.3  64.9  165  18  9  10.3   5.6
  8500  18.6  65.5  170  16  8  10.6   5.8 |  19.1  66.4  165  18  9  10.5   5.8
  8250  19.4  66.9  170  16  8  11.0   6.0 |  19.9  67.8  165  17  9  10.5   5.7
  8000  20.2  68.4  170  16  8  10.3   5.7 |  20.7  69.3  165  17  9  10.6   5.8
  7750  21.0  69.8  170  16  8  12.5   6.9 |  21.4  70.5  165  17  9  10.1   5.6
  7500  22.0  71.6  170  15  8  13.2   7.2 |  22.1  71.8  165  16  8   8.4   4.6
  7250  22.8  73.0  170  15  8  11.0   6.0 |  22.7  72.9  165  15  8   7.4   4.1
  7000  23.6  74.5  165  14  7  12.9   7.1 |  23.2  73.8  165  14  7   8.1   4.5
  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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