Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 071235
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0635 MDT Tuesday, July 7, 2015

This forecast is for Tuesday, July 7, 2015:

If the trigger temperature of 61.8 F/16.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 155 ft/min (0.8 m/s)
   Maximum height of thermals.................. 11321 ft MSL (4563 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1400 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9859 ft MSL (3101 ft AGL)
Thermal soaring outlook for Wednesday 07/08.... Fair

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

Remarks...

Sunrise/Sunset.................... 05:40:29 / 20:27:22 MDT
Total possible sunshine........... 14 hr 46 min 53 sec (886 min 53 sec)
Altitude of sun at 13:03:55 MDT... 73.57 degrees

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

Freezing level.................. 15044 ft MSL (8286 ft AGL)
Convective condensation level... 11224 ft MSL (4466 ft AGL)
Lifted condensation level....... 10914 ft MSL (4156 ft AGL)
Lifted index.................... +1.5
K index......................... +25.9

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  -62.8 -81.0   235   32   17   1.9   1.0      M     M       M      M    M
 45000  -59.3 -74.7   240   47   24   3.2   1.7      M     M       M      M    M
 40000  -53.9 -65.0   245   54   28   7.3   4.0      M     M       M      M    M
 38000  -49.4 -56.9   245   45   23   7.4   4.1      M     M       M      M    M
 36000  -45.0 -49.0   250   37   19   7.3   4.0      M     M       M      M    M
 34000  -39.4 -38.9   250   29   15   8.4   4.6      M     M       M      M    M
 32000  -34.3 -29.7   250   22   11   9.1   5.0      M     M       M      M    M
 30000  -29.4 -20.9   250   18    9   8.3   4.5   41.1 106.0    18.0      M    M
 29000  -26.9 -16.4   250   17    9   8.3   4.6   40.6 105.1    17.8      M    M
 28000  -24.4 -11.9   250   15    8   7.6   4.2   40.2 104.3    17.6      M    M
 27000  -22.3  -8.1   250   15    8   7.3   4.0   39.1 102.4    17.0      M    M
 26000  -20.1  -4.2   250   14    7   7.4   4.0   38.2 100.8    16.4      M    M
 25000  -17.9  -0.2   255   14    7   7.4   4.0   37.5  99.4    15.9      M    M
 24000  -15.9   3.4   255   13    7   6.7   3.7   36.3  97.4    15.2      M    M
 23000  -13.9   7.0   260   13    7   6.7   3.7   35.2  95.4    14.4      M    M
 22000  -11.9  10.6   260   13    6   6.7   3.7   34.3  93.7    13.7      M    M
 21000  -10.1  13.8   255   12    6   6.0   3.3   32.9  91.2    12.6      M    M
 20000   -8.4  16.9   250   11    6   6.1   3.3   31.6  88.9    11.5      M    M
 19500   -7.6  18.3   245   11    6   6.2   3.4   31.0  87.9    11.0      M    M
 19000   -6.7  19.9   240   11    6   5.7   3.1   30.4  86.8    10.5      M    M
 18500   -5.9  21.4   240   11    6   5.7   3.1   29.7  85.5     9.9      M    M
 18000   -5.1  22.8   235   11    5   5.8   3.2   29.0  84.3     9.3      M    M
 17500   -4.2  24.4   230   10    5   6.5   3.6   28.4  83.2     8.8      M    M
 17000   -3.3  26.1   220   10    5   6.6   3.6   27.9  82.2     8.3      M    M
 16500   -2.4  27.7   215   10    5   4.8   2.6   27.2  81.0     7.7      M    M
 16000   -1.4  29.5   210    9    5   4.2   2.3   25.9  78.7     6.5      M    M
 15500   -0.7  30.7   205    9    5   6.6   3.6   25.2  77.4     5.9      M    M
 15000    0.3  32.5   200    9    5   6.6   3.6   24.7  76.4     5.4      M    M
 14500    1.2  34.2   195   10    5   5.4   3.0   24.1  75.4     4.9      M    M
 14000    1.9  35.4   190   10    5   5.0   2.7   23.3  74.0     4.1      M    M
 13500    2.6  36.7   190   10    5   4.9   2.7   22.6  72.6     3.4      M    M
 13000    3.3  37.9   185   11    5   4.9   2.7   21.8  71.2     2.6      M    M
 12500    3.9  39.0   180   11    6   5.0   2.7   21.0  69.9     1.9      M    M
 12000    4.6  40.3   180   11    6   4.2   2.3   20.2  68.4     1.1      M    M
 11750    4.9  40.8   175   11    6   4.2   2.3   19.8  67.6     0.6      M    M
 11500    5.2  41.4   175   11    6   4.5   2.5   19.3  66.8     0.2      M    M
 11250    5.5  41.9   180   11    6   4.4   2.4   18.9  66.1    -0.2    346  1.8
 11000    5.8  42.4   185   12    6   2.7   1.5   18.5  65.2    -0.7    331  1.7
 10750    5.9  42.6   185   12    6   1.4   0.8   17.8  64.1    -1.3    320  1.6
 10500    6.0  42.8   190   13    7   2.6   1.4   17.2  63.0    -1.9    309  1.6
 10250    6.3  43.3   190   14    7   4.7   2.6   16.8  62.2    -2.4    294  1.5
 10000    6.6  43.9   190   14    7   4.1   2.3   16.4  61.5    -2.8    276  1.4
  9750    6.8  44.2   190   15    8   2.5   1.4   15.9  60.6    -3.3    263  1.3
  9500    7.0  44.6   190   17    9   1.8   1.0   15.3  59.5    -3.9    250  1.3
  9250    7.1  44.8   185   17    9   1.1   0.6   14.6  58.4    -4.5    240  1.2
  9000    7.2  45.0   180   17    9   1.1   0.6   14.0  57.2    -5.2    230  1.2
  8750    7.3  45.1   180   17    9   2.3   1.3   13.4  56.0    -5.8    219  1.1
  8500    7.6  45.7   175   18    9   6.3   3.4   12.9  55.3    -6.3    203  1.0
  8250    8.1  46.6   175   17    9   8.3   4.5   12.8  55.0    -6.5    180  0.9
  8000    8.6  47.5   175   17    9   7.7   4.2   12.6  54.7    -6.7    156  0.8
  7750    9.2  48.6   175   16    8   8.0   4.4   12.5  54.5    -6.9    132  0.7
  7500    9.7  49.5   175   15    8   6.4   3.5   12.5  54.5    -6.9    109  0.6
  7250   10.1  50.2   175   13    7   4.8   2.6   12.5  54.5    -6.9     91  0.5
  7000   10.4  50.7   175   11    6   6.0   3.3   12.5  54.5    -7.0     72  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           07/07/2015 at 0900 MDT          |       07/07/2015 at 1200 MDT
                                           |
K index... +27.2  LI... +274.0             | K index... +26.3  LI... +273.9
CAPE... 0.0  CIN... -3.3                   | CAPE... 0.0  CIN... -1.4
                                           |
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 -62.3 -80.1  245  34 17   2.0   1.1 | -62.7 -80.9  245  35 18   1.7   0.9
 45000 -59.4 -74.9  245  47 24   1.7   0.9 | -59.9 -75.8  240  47 24   2.3   1.3
 40000 -55.7 -68.3  240  53 27   8.8   4.8 | -55.5 -67.9  225  55 28   8.6   4.7
 38000 -50.2 -58.4  245  46 24   9.1   5.0 | -50.1 -58.2  220  51 26   8.8   4.8
 36000 -44.8 -48.6  245  40 20   9.1   5.0 | -44.8 -48.6  215  47 24   8.8   4.8
 34000 -39.0 -38.2  245  31 16   8.5   4.7 | -38.8 -37.8  225  41 21   9.0   5.0
 32000 -33.8 -28.8  240  23 12   9.3   5.1 | -33.3 -27.9  235  36 19   9.9   5.4
 30000 -29.1 -20.4  230  21 11   8.0   4.4 | -28.7 -19.7  240  31 16   7.5   4.1
 29000 -26.7 -16.1  225  21 11   8.0   4.4 | -26.4 -15.5  240  28 14   7.5   4.1
 28000 -24.3 -11.7  220  21 11   7.5   4.1 | -24.2 -11.6  240  25 13   7.5   4.1
 27000 -22.2  -8.0  215  20 10   7.3   4.0 | -21.9  -7.4  235  23 12   7.6   4.2
 26000 -20.0  -4.0  215  20 10   7.3   4.0 | -19.7  -3.5  230  22 11   7.6   4.2
 25000 -17.9  -0.2  210  20 10   7.4   4.0 | -17.4   0.7  230  20 10   7.6   4.2
 24000 -15.8   3.6  210  19 10   6.8   3.7 | -15.4   4.3  230  19 10   6.6   3.6
 23000 -13.8   7.2  205  18  9   6.8   3.8 | -13.5   7.7  230  17  9   6.6   3.6
 22000 -11.8  10.8  205  18  9   6.8   3.7 | -11.5  11.3  230  16  8   6.6   3.6
 21000 -10.0  14.0  205  17  9   6.1   3.4 |  -9.7  14.5  235  15  8   6.1   3.4
 20000  -8.3  17.1  205  17  9   6.1   3.4 |  -8.0  17.6  240  14  7   6.2   3.4
 19500  -7.4  18.7  205  17  9   6.2   3.4 |  -7.1  19.2  240  13  7   6.2   3.4
 19000  -6.5  20.3  205  17  9   5.7   3.1 |  -6.2  20.8  245  13  6   6.0   3.3
 18500  -5.7  21.7  205  16  8   5.6   3.1 |  -5.4  22.3  250  12  6   6.0   3.3
 18000  -4.9  23.2  205  15  8   5.6   3.1 |  -4.5  23.9  255  12  6   5.9   3.2
 17500  -4.1  24.6  205  15  8   5.5   3.0 |  -3.8  25.2  260  12  6   4.8   2.6
 17000  -3.3  26.1  205  14  7   5.5   3.0 |  -3.1  26.4  260  11  6   4.9   2.7
 16500  -2.3  27.9  205  14  7   4.3   2.4 |  -2.4  27.7  265  11  6   4.9   2.7
 16000  -1.7  28.9  200  13  7   4.4   2.4 |  -1.4  29.5  260  11  5   4.9   2.7
 15500  -1.1  30.0  200  13  7   4.2   2.3 |  -0.6  30.9  255  10  5   5.2   2.8
 15000  -0.5  31.1  200  13  7   4.2   2.3 |   0.1  32.2  250  10  5   5.2   2.8
 14500   0.2  32.4  200  13  7   5.0   2.8 |   0.8  33.4  245  11  5   5.2   2.9
 14000   1.0  33.8  205  12  6   5.4   3.0 |   1.6  34.9  240  11  6   5.3   2.9
 13500   1.7  35.1  205  11  6   5.7   3.1 |   2.3  36.1  235  11  6   5.5   3.0
 13000   2.6  36.7  205  11  6   5.9   3.2 |   3.1  37.6  230  12  6   5.7   3.1
 12500   3.4  38.1  205  12  6   5.5   3.0 |   3.9  39.0  225  12  6   5.4   3.0
 12000   4.3  39.7  210  11  6   7.2   4.0 |   4.7  40.5  220  12  6   5.6   3.1
 11750   4.8  40.6  210  11  6   7.1   3.9 |   5.1  41.2  220  12  6   5.6   3.1
 11500   5.3  41.5  210  11  6   6.5   3.6 |   5.5  41.9  220  12  6   5.3   2.9
 11250   5.7  42.3  210  11  6   5.1   2.8 |   5.8  42.4  220  12  6   4.4   2.4
 11000   6.1  43.0  215  12  6   4.9   2.7 |   6.1  43.0  215  12  6   3.9   2.1
 10750   6.4  43.5  215  12  6   5.3   2.9 |   6.4  43.5  215  13  7   4.0   2.2
 10500   6.8  44.2  215  12  6   4.3   2.4 |   6.7  44.1  210  13  7   3.4   1.9
 10250   7.0  44.6  210  13  7   2.6   1.4 |   6.9  44.4  205  14  7   1.9   1.1
 10000   7.2  45.0  210  14  7   2.5   1.4 |   7.0  44.6  200  15  8   1.6   0.9
  9750   7.4  45.3  210  15  8   3.3   1.8 |   7.1  44.8  200  16  8   1.9   1.0
  9500   7.6  45.7  210  16  8   2.5   1.4 |   7.2  45.0  195  17  9   2.1   1.1
  9250   7.7  45.9  205  16  8   1.4   0.8 |   7.4  45.3  190  18  9   2.5   1.3
  9000   7.8  46.0  205  16  8   1.6   0.9 |   7.6  45.7  185  18  9   2.6   1.4
  8750   7.9  46.2  200  16  8   0.2   0.1 |   7.8  46.0  185  19 10   3.4   1.8
  8500   8.0  46.4  200  17  9   3.2   1.8 |   8.1  46.6  180  21 11   6.1   3.3
  8250   8.4  47.1  195  16  8   6.8   3.7 |   8.6  47.5  180  20 10   8.1   4.5
  8000   8.8  47.8  195  15  8   5.5   3.0 |   9.1  48.4  175  19 10   6.4   3.5
  7750   9.2  48.6  190  14  7   7.1   3.9 |   9.7  49.5  175  18  9  11.6   6.4
  7500   9.8  49.6  180  13  7   7.5   4.1 |  10.7  51.3  170  17  9  13.3   7.3
  7250  10.2  50.4  180  12  6   6.1   3.4 |  11.4  52.5  170  16  8   8.4   4.6
  7000  10.7  51.3  180  11  6   7.3   4.0 |  12.1  53.8  165  15  8  12.6   6.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           07/07/2015 at 1500 MDT          |       07/07/2015 at 1800 MDT
                                           |
K index... +25.6  LI... +274.4             | K index... +24.6  LI... +273.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.5
                                           |
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 -63.2 -81.8  240  37 19   1.7   0.9 | -62.9 -81.2  240  35 18   1.8   1.0
 45000 -60.2 -76.4  230  46 24   2.7   1.5 | -59.8 -75.6  230  43 22   2.7   1.5
 40000 -55.1 -67.2  210  48 25   9.2   5.1 | -54.8 -66.6  210  39 20   8.6   4.7
 38000 -49.5 -57.1  215  41 21   9.4   5.2 | -49.5 -57.1  215  37 19   8.8   4.8
 36000 -43.8 -46.8  220  35 18   9.5   5.2 | -44.2 -47.6  215  35 18   8.8   4.8
 34000 -37.8 -36.0  230  30 15   8.7   4.8 | -38.0 -36.4  225  31 16   9.2   5.1
 32000 -32.6 -26.7  235  26 13   9.6   5.3 | -32.5 -26.5  235  28 14   9.2   5.0
 30000 -27.9 -18.2  235  23 12   7.7   4.2 | -27.7 -17.9  235  23 12   7.9   4.3
 29000 -25.7 -14.3  235  21 11   7.7   4.2 | -25.3 -13.5  235  21 11   7.9   4.3
 28000 -23.4 -10.1  230  20 10   7.3   4.0 | -23.0  -9.4  240  19 10   7.1   3.9
 27000 -21.3  -6.3  230  19 10   7.1   3.9 | -21.0  -5.8  240  19 10   6.7   3.7
 26000 -19.2  -2.6  230  18  9   7.1   3.9 | -19.1  -2.4  240  19 10   6.7   3.7
 25000 -17.1   1.2  230  17  9   7.2   3.9 | -17.1   1.2  240  19 10   6.7   3.7
 24000 -15.2   4.6  235  16  8   6.4   3.5 | -15.2   4.6  240  18  9   6.5   3.5
 23000 -13.3   8.1  240  15  7   6.4   3.5 | -13.3   8.1  240  16  8   6.5   3.6
 22000 -11.4  11.5  245  13  7   6.4   3.5 | -11.4  11.5  240  15  8   6.6   3.6
 21000  -9.5  14.9  250  12  6   6.4   3.5 |  -9.8  14.4  240  14  7   5.3   2.9
 20000  -7.7  18.1  250  10  5   6.5   3.6 |  -8.2  17.2  240  13  7   5.4   2.9
 19500  -6.7  19.9  255  10  5   6.5   3.6 |  -7.5  18.5  240  12  6   5.4   3.0
 19000  -5.8  21.6  255   9  5   5.7   3.1 |  -6.7  19.9  240  12  6   5.3   2.9
 18500  -5.1  22.8  255   9  4   5.4   3.0 |  -5.9  21.4  245  11  6   5.3   2.9
 18000  -4.3  24.3  255   8  4   5.4   3.0 |  -5.2  22.6  250  11  6   5.3   2.9
 17500  -3.5  25.7  255   8  4   5.5   3.0 |  -4.3  24.3  250  11  6   5.8   3.2
 17000  -2.7  27.1  255   7  4   5.5   3.0 |  -3.5  25.7  255  11  6   5.8   3.2
 16500  -2.0  28.4  250   7  4   5.3   2.9 |  -2.6  27.3  260  11  6   6.0   3.3
 16000  -0.8  30.6  250   7  4   5.2   2.8 |  -1.3  29.7  265  11  6   6.1   3.3
 15500  -0.1  31.8  245   8  4   5.3   2.9 |  -0.3  31.5  270  11  6   7.2   3.9
 15000   0.7  33.3  240   8  4   5.3   2.9 |   0.8  33.4  270  11  5   7.3   4.0
 14500   1.5  34.7  240   9  5   6.1   3.3 |   1.8  35.2  270  10  5   7.9   4.3
 14000   2.4  36.3  240  10  5   6.7   3.7 |   3.1  37.6  270  11  5   8.3   4.6
 13500   3.4  38.1  235  10  5   6.2   3.4 |   4.3  39.7  265  11  5   8.1   4.4
 13000   4.1  39.4  235  11  6   4.9   2.7 |   5.4  41.7  260  11  6   7.2   3.9
 12500   4.8  40.6  235  12  6   5.6   3.1 |   6.4  43.5  260  11  6   8.5   4.7
 12000   5.6  42.1  230  13  7   4.9   2.7 |   7.4  45.3  255  12  6   4.4   2.4
 11750   6.0  42.8  225  13  7   5.3   2.9 |   7.7  45.9  255  12  6   5.2   2.8
 11500   6.3  43.3  225  14  7   4.6   2.5 |   8.1  46.6  250  13  7   4.9   2.7
 11250   6.6  43.9  225  14  7   1.5   0.8 |   8.3  46.9  250  13  7   0.1   0.0
 11000   6.6  43.9  220  15  8   1.1   0.6 |   8.1  46.6  240  13  7  -1.8  -1.0
 10750   6.7  44.1  215  15  8   2.5   1.4 |   8.0  46.4  235  14  7   0.2   0.1
 10500   6.9  44.4  215  16  8   2.0   1.1 |   7.9  46.2  230  15  8  -0.3  -0.2
 10250   7.0  44.6  210  17  9   1.6   0.9 |   7.9  46.2  225  16  8   0.3   0.2
 10000   7.1  44.8  205  18  9   1.2   0.7 |   7.9  46.2  220  16  8   0.3   0.1
  9750   7.2  45.0  200  19 10   1.0   0.5 |   7.9  46.2  210  18  9  -0.3  -0.2
  9500   7.2  45.0  195  21 11   1.2   0.7 |   7.8  46.0  205  20 10   0.2   0.1
  9250   7.3  45.1  190  22 11   2.1   1.1 |   7.9  46.2  200  21 11   3.1   1.7
  9000   7.5  45.5  190  23 12   2.3   1.3 |   8.2  46.8  195  21 11   4.8   2.6
  8750   7.7  45.9  185  23 12   4.4   2.4 |   8.5  47.3  195  22 11   5.2   2.9
  8500   8.1  46.6  185  24 12   6.6   3.6 |   8.9  48.0  190  23 12   5.9   3.2
  8250   8.5  47.3  180  23 12   7.2   3.9 |   9.3  48.7  185  22 11   6.0   3.3
  8000   9.1  48.4  180  22 11   6.5   3.6 |   9.7  49.5  185  21 11   5.0   2.8
  7750   9.6  49.3  180  21 11   9.3   5.1 |  10.1  50.2  180  19 10   8.7   4.8
  7500  10.3  50.5  175  19 10  10.9   6.0 |  10.9  51.6  175  17  9   9.7   5.3
  7250  11.0  51.8  175  18  9   8.7   4.8 |  11.4  52.5  175  16  8   6.0   3.3
  7000  11.7  53.1  175  16  8  10.6   5.8 |  11.9  53.4  175  15  8   8.9   4.9
  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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