Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 251058
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0458 MDT Monday, April 25, 2016

This forecast is for Monday, April 25, 2016:

If the trigger temperature of 56.8 F/13.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 991 ft/min (5.0 m/s)
   Maximum height of thermals.................. 17725 ft MSL (10557 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 15046 ft MSL (7878 ft AGL)
Thermal soaring outlook for Tuesday 04/26...... Good

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

Remarks...

Sunrise/Sunset.................... 06:08:00 / 19:45:30 MDT
Total possible sunshine........... 13 hr 37 min 30 sec (817 min 30 sec)
Altitude of sun at 12:56:55 MDT... 64.56 degrees

Upper air data from numerical model forecast valid on 04/25/2016 at 0600 MDT

Freezing level.................. 11874 ft MSL (4706 ft AGL)
Convective condensation level... 17795 ft MSL (10627 ft AGL)
Lifted condensation level....... 17920 ft MSL (10752 ft AGL)
Lifted index.................... -1.0
K index......................... +10.1

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  -59.8 -75.6   240   38   20   2.3   1.3      M     M       M      M    M
 45000  -56.3 -69.3   240   66   34   0.7   0.4      M     M       M      M    M
 40000  -57.6 -71.7   240   80   41  -0.8  -0.5      M     M       M      M    M
 38000  -56.5 -69.7   235   82   42   4.7   2.6      M     M       M      M    M
 36000  -53.4 -64.1   235   82   42   4.7   2.6      M     M       M      M    M
 34000  -50.3 -58.5   230   80   41   6.8   3.8      M     M       M      M    M
 32000  -46.2 -51.2   235   71   37   6.8   3.7      M     M       M      M    M
 30000  -42.1 -43.8   240   63   33   7.0   3.9   27.9  82.3     7.4      M    M
 29000  -40.0 -40.0   240   60   31   7.0   3.9   26.8  80.2     6.6      M    M
 28000  -37.9 -36.2   240   57   30   7.0   3.9   25.8  78.4     5.8      M    M
 27000  -35.8 -32.4   245   54   28   6.9   3.8   24.9  76.8     5.2      M    M
 26000  -33.8 -28.8   245   52   27   6.5   3.6   23.6  74.5     4.2      M    M
 25000  -31.9 -25.4   245   50   26   6.6   3.6   22.4  72.3     3.3      M    M
 24000  -29.9 -21.8   245   47   24   6.4   3.5   21.3  70.4     2.4      M    M
 23000  -26.7 -16.1   245   46   24   9.3   5.1   20.8  69.5     2.0      M    M
 22000  -23.9 -11.0   240   45   23   9.3   5.1   20.7  69.2     1.9      M    M
 21000  -21.2  -6.2   240   43   22   8.4   4.6   20.5  68.9     1.7      M    M
 20000  -18.7  -1.7   240   42   21   8.3   4.6   19.9  67.9     1.3      M    M
 19500  -17.5   0.5   240   41   21   8.3   4.6   19.7  67.4     1.0      M    M
 19000  -16.3   2.7   240   40   20   8.3   4.6   19.5  67.1     0.9      M    M
 18500  -15.0   5.0   240   39   20   7.5   4.1   19.3  66.7     0.7      M    M
 18000  -14.0   6.8   240   38   19   7.0   3.8   18.8  65.8     0.2      M    M
 17500  -13.0   8.6   240   36   19   7.0   3.8   18.3  65.0    -0.2    969  4.9
 17000  -12.1  10.2   245   35   18   5.7   3.1   17.7  63.9    -0.8    927  4.7
 16500  -11.2  11.8   245   33   17   5.8   3.2   17.1  62.7    -1.4    887  4.5
 16000  -10.3  13.5   245   31   16   6.4   3.5   16.5  61.6    -2.0    846  4.3
 15500   -9.4  15.1   245   29   15   6.6   3.6   15.9  60.6    -2.5    803  4.1
 15000   -8.4  16.9   250   27   14   7.3   4.0   15.4  59.7    -3.0    760  3.9
 14500   -7.2  19.0   250   25   13   8.4   4.6   15.1  59.3    -3.3    708  3.6
 14000   -6.0  21.2   245   23   12   8.5   4.6   14.9  58.9    -3.5    656  3.3
 13500   -4.7  23.5   245   22   11   8.7   4.8   14.7  58.5    -3.7    603  3.1
 13000   -3.4  25.9   245   21   11   8.6   4.7   14.6  58.2    -3.9    549  2.8
 12500   -1.9  28.6   245   21   11  11.0   6.0   14.6  58.2    -3.9    490  2.5
 12000   -0.5  31.1   250   21   11   7.8   4.3   14.5  58.2    -3.9    433  2.2
 11750    0.1  32.2   250   21   11   8.3   4.6   14.4  57.9    -4.1    408  2.1
 11500    0.7  33.3   250   21   11   8.8   4.8   14.3  57.8    -4.2    381  1.9
 11250    1.4  34.5   250   20   10   8.6   4.7   14.2  57.6    -4.3    354  1.8
 11000    2.0  35.6   245   19   10   9.0   4.9   14.2  57.5    -4.4    327  1.7
 10750    2.7  36.9   245   19   10   8.5   4.7   14.1  57.4    -4.4    300  1.5
 10500    3.3  37.9   245   18    9   7.9   4.3   13.9  57.1    -4.6    275  1.4
 10250    3.9  39.0   245   17    9   7.6   4.2   13.8  56.8    -4.8    250  1.3
 10000    4.5  40.1   245   17    9   9.3   5.1   13.7  56.6    -4.9    225  1.1
  9750    5.2  41.4   245   16    8   8.7   4.8   13.7  56.6    -4.9    196  1.0
  9500    6.2  43.2   240   14    7   6.5   3.6   13.2  55.8    -5.4    152  0.8
  9250    6.6  43.9   235   14    7   6.7   3.7   13.0  55.3    -5.7    131  0.7
  9000    7.0  44.6   235   13    7   2.2   1.2   12.6  54.7    -6.1    112  0.6
  8750    7.0  44.6   225   13    6   0.3   0.1   11.9  53.4    -6.9    106  0.5
  8500    7.1  44.8   220   12    6   2.9   1.6   11.3  52.3    -7.5     95  0.5
  8250    7.2  45.0   215   12    6   0.8   0.4   10.7  51.3    -8.1     83  0.4
  8000    7.1  44.8   210   12    6  -4.8  -2.6    9.9  49.7    -9.0     81  0.4
  7750    6.4  43.5   205   11    5 -12.0  -6.6    8.5  47.3   -10.4     93  0.5
  7500    5.3  41.5   205    8    4 -16.4  -9.0    6.7  44.0   -12.3    120  0.6
  7250    4.1  39.4   210    5    2 -10.6  -5.8    4.8  40.7   -14.2    146  0.7
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           04/25/2016 at 0900 MDT          |       04/25/2016 at 1200 MDT
                                           |
K index... +2.4  LI... +275.0              | K index... -11.0  LI... +275.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -59.3 -74.7  230  42 22   1.8   1.0 | -58.8 -73.8  225  41 21   1.1   0.6
 45000 -56.5 -69.7  240  67 35   0.6   0.3 | -57.2 -71.0  235  60 31   0.3   0.2
 40000 -58.3 -72.9  240  78 40  -1.2  -0.7 | -58.9 -74.0  235  74 38  -1.1  -0.6
 38000 -57.4 -71.3  240  80 41   4.6   2.5 | -58.0 -72.4  230  78 40   4.6   2.5
 36000 -54.3 -65.7  235  79 40   4.6   2.5 | -54.9 -66.8  235  80 41   4.6   2.5
 34000 -51.3 -60.3  235  76 39   6.6   3.6 | -51.9 -61.4  235  80 41   6.8   3.7
 32000 -47.4 -53.3  235  67 35   6.6   3.6 | -47.9 -54.2  235  76 39   6.8   3.7
 30000 -43.2 -45.8  235  59 30   8.7   4.8 | -43.6 -46.5  235  71 37   8.3   4.6
 29000 -40.6 -41.1  235  57 29   8.7   4.8 | -41.1 -42.0  240  69 35   8.4   4.6
 28000 -38.0 -36.4  235  55 28   8.7   4.8 | -38.6 -37.5  240  66 34   8.4   4.6
 27000 -35.4 -31.7  235  53 27   8.6   4.7 | -36.1 -33.0  240  64 33   8.4   4.6
 26000 -32.9 -27.2  235  53 27   8.2   4.5 | -33.6 -28.5  240  59 30   8.3   4.5
 25000 -30.5 -22.9  240  54 28   8.2   4.5 | -31.1 -24.0  240  53 27   8.3   4.5
 24000 -28.0 -18.4  240  55 28   8.5   4.6 | -28.7 -19.7  235  47 24   8.3   4.5
 23000 -25.7 -14.3  240  53 27   5.8   3.2 | -25.5 -13.9  235  46 24   8.5   4.7
 22000 -24.0 -11.2  235  52 27   5.8   3.2 | -22.9  -9.2  235  46 24   8.5   4.7
 21000 -22.2  -8.0  235  50 26   7.3   4.0 | -20.5  -4.9  235  46 24   7.5   4.1
 20000 -19.9  -3.8  235  46 24   7.6   4.2 | -18.2  -0.8  235  46 24   7.4   4.0
 19500 -18.8  -1.8  240  43 22   7.6   4.2 | -17.1   1.2  240  46 24   7.4   4.0
 19000 -17.7   0.1  240  41 21   7.6   4.2 | -16.0   3.2  240  46 24   7.3   4.0
 18500 -16.6   2.1  240  39 20   7.9   4.4 | -14.9   5.2  240  46 24   6.2   3.4
 18000 -15.3   4.5  235  35 18   8.2   4.5 | -14.2   6.4  240  45 23   5.4   2.9
 17500 -14.1   6.6  235  32 17   8.2   4.5 | -13.4   7.9  240  45 23   5.3   2.9
 17000 -12.9   8.8  235  32 17   7.9   4.3 | -12.4   9.7  240  43 22   7.2   4.0
 16500 -11.7  10.9  235  34 18   8.0   4.4 | -11.4  11.5  240  41 21   7.1   3.9
 16000 -10.6  12.9  240  35 18   7.2   3.9 | -10.3  13.5  235  39 20   7.4   4.1
 15500  -9.6  14.7  240  33 17   7.0   3.9 |  -9.2  15.4  235  36 19   7.5   4.1
 15000  -8.6  16.5  240  32 16   7.4   4.0 |  -8.1  17.4  235  33 17   7.4   4.1
 14500  -7.4  18.7  240  29 15   7.8   4.3 |  -7.0  19.4  235  31 16   7.3   4.0
 14000  -6.3  20.7  240  27 14   8.0   4.4 |  -6.0  21.2  235  29 15   7.4   4.0
 13500  -5.1  22.8  240  25 13   8.6   4.7 |  -4.9  23.2  230  27 14   7.5   4.1
 13000  -3.8  25.2  240  22 12   8.5   4.7 |  -3.8  25.2  225  25 13   7.5   4.1
 12500  -2.4  27.7  240  21 11  11.2   6.2 |  -2.6  27.3  225  23 12   9.2   5.0
 12000  -0.9  30.4  240  20 11   7.8   4.3 |  -1.4  29.5  220  21 11   6.9   3.8
 11750  -0.3  31.5  240  20 10   8.7   4.8 |  -0.9  30.4  220  20 10   7.9   4.3
 11500   0.4  32.7  235  20 10   9.7   5.3 |  -0.3  31.5  220  19 10   8.8   4.9
 11250   1.1  34.0  235  20 10   9.3   5.1 |   0.4  32.7  220  19 10   8.5   4.7
 11000   1.8  35.2  235  20 11   9.9   5.5 |   1.0  33.8  215  19 10   9.0   4.9
 10750   2.5  36.5  235  21 11   8.6   4.7 |   1.7  35.1  215  19 10   8.6   4.7
 10500   3.1  37.6  235  21 11   7.1   3.9 |   2.2  36.0  215  19 10   8.0   4.4
 10250   3.6  38.5  235  21 11   7.0   3.8 |   2.8  37.0  210  18 10   7.7   4.2
 10000   4.2  39.6  230  21 11   8.3   4.6 |   3.4  38.1  210  18  9   9.3   5.1
  9750   4.8  40.6  230  21 11   7.4   4.1 |   4.1  39.4  205  18  9   9.9   5.4
  9500   5.6  42.1  225  20 10   5.8   3.2 |   5.4  41.7  200  18  9   8.8   4.8
  9250   6.0  42.8  225  19 10   5.6   3.1 |   6.0  42.8  195  18  9   8.5   4.7
  9000   6.4  43.5  220  18  9   2.8   1.5 |   6.6  43.9  190  18  9   8.6   4.7
  8750   6.4  43.5  215  18  9   1.8   1.0 |   7.3  45.1  185  17  9   9.9   5.4
  8500   6.6  43.9  210  17  9   3.3   1.8 |   8.0  46.4  185  17  9  10.6   5.8
  8250   6.8  44.2  205  16  8   2.9   1.6 |   8.8  47.8  185  17  9  10.4   5.7
  8000   6.9  44.4  200  15  8   2.4   1.3 |   9.6  49.3  185  17  9  10.3   5.7
  7750   7.2  45.0  195  13  7   8.1   4.4 |  10.5  50.9  180  16  8  16.7   9.2
  7500   8.1  46.6  190  11  6  18.6  10.2 |  12.1  53.8  180  16  8  27.4  15.0
  7250   9.1  48.4  185  10  5  -0.2  -0.1 |  13.8  56.8  180  15  8   8.6   4.7
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           04/25/2016 at 1500 MDT          |       04/25/2016 at 1800 MDT
                                           |
K index... -1.3  LI... +274.3              | K index... +14.7  LI... +273.2
CAPE... +5.5  CIN... -48.6                 | CAPE... 0.0  CIN... -29.9
                                           |
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 -58.1 -72.6  230  34 17   1.2   0.7 | -57.8 -72.0  245  23 12   1.6   0.9
 45000 -56.2 -69.2  235  51 26   0.1   0.0 | -55.3 -67.5  235  29 15   0.3   0.2
 40000 -58.2 -72.8  230  77 39  -1.4  -0.7 | -57.8 -72.0  230  66 34  -1.7  -0.9
 38000 -57.7 -71.9  230  83 43   3.5   1.9 | -57.6 -71.7  230  75 39   3.1   1.7
 36000 -55.6 -68.1  230  85 44   3.5   1.9 | -55.8 -68.4  225  78 40   3.1   1.7
 34000 -53.2 -63.8  230  87 45   7.5   4.1 | -53.7 -64.7  225  81 42   7.2   4.0
 32000 -49.0 -56.2  230  80 41   7.0   3.9 | -49.3 -56.7  225  73 38   7.4   4.0
 30000 -44.6 -48.3  230  74 38   9.3   5.1 | -44.8 -48.6  225  67 35   8.8   4.8
 29000 -41.8 -43.2  230  71 36   9.1   5.0 | -42.2 -44.0  225  67 35   8.6   4.7
 28000 -38.4 -37.1  230  67 34   9.1   5.0 | -39.0 -38.2  225  68 35   8.6   4.7
 27000 -35.7 -32.3  225  64 33   7.6   4.2 | -36.4 -33.5  225  68 35   8.4   4.6
 26000 -33.7 -28.7  225  62 32   6.7   3.7 | -34.0 -29.2  230  67 34   8.2   4.5
 25000 -31.7 -25.1  225  60 31   6.7   3.7 | -31.5 -24.7  230  66 34   8.2   4.5
 24000 -29.7 -21.5  220  58 30   7.6   4.2 | -29.0 -20.2  230  65 34   8.1   4.5
 23000 -26.8 -16.2  220  55 28   9.7   5.3 | -26.7 -16.1  230  63 32   7.8   4.3
 22000 -23.9 -11.0  220  52 27   9.7   5.3 | -24.4 -11.9  230  61 31   7.8   4.3
 21000 -21.0  -5.8  220  50 26   7.9   4.4 | -22.1  -7.8  230  58 30   7.7   4.2
 20000 -18.9  -2.0  230  51 26   7.2   3.9 | -19.8  -3.6  225  53 27   7.5   4.1
 19500 -17.8  -0.0  230  51 26   7.2   3.9 | -18.7  -1.7  225  51 26   7.5   4.1
 19000 -16.7   1.9  235  52 27   7.2   3.9 | -17.6   0.3  220  48 25   7.5   4.1
 18500 -15.6   3.9  235  53 27   7.2   4.0 | -16.5   2.3  220  46 24   7.7   4.2
 18000 -14.5   5.9  240  51 26   7.2   4.0 | -15.3   4.5  215  43 22   8.1   4.5
 17500 -13.4   7.9  240  49 25   7.2   3.9 | -14.1   6.6  215  41 21   8.1   4.4
 17000 -12.3   9.9  240  47 24   7.9   4.3 | -12.8   9.0  210  38 20   8.7   4.8
 16500 -11.1  12.0  240  44 23   7.9   4.3 | -11.6  11.1  210  36 18   8.7   4.8
 16000 -10.0  14.0  240  41 21   7.6   4.2 | -10.3  13.5  205  33 17   8.6   4.7
 15500  -8.9  16.0  240  38 20   7.6   4.1 |  -9.0  15.8  200  32 16   8.6   4.7
 15000  -7.8  18.0  240  35 18   7.6   4.2 |  -7.7  18.1  195  30 15   8.7   4.7
 14500  -6.7  19.9  240  32 16   7.7   4.2 |  -6.4  20.5  195  29 15   8.9   4.9
 14000  -5.5  22.1  240  29 15   7.8   4.3 |  -5.1  22.8  190  28 15   8.9   4.9
 13500  -4.4  24.1  235  27 14   7.9   4.3 |  -3.8  25.2  185  28 14   8.8   4.8
 13000  -3.3  26.1  230  25 13   7.8   4.3 |  -2.5  27.5  180  28 14   8.7   4.8
 12500  -2.1  28.2  225  24 12   9.2   5.0 |  -1.1  30.0  180  28 14  11.2   6.2
 12000  -0.8  30.6  215  23 12   7.7   4.2 |   0.3  32.5  175  27 14   6.5   3.5
 11750  -0.2  31.6  215  23 12   8.1   4.4 |   0.8  33.4  175  27 14   7.7   4.2
 11500   0.4  32.7  210  22 12   8.5   4.7 |   1.4  34.5  175  27 14   9.1   5.0
 11250   1.0  33.8  205  22 11   8.5   4.7 |   2.2  36.0  175  26 14  10.0   5.5
 11000   1.6  34.9  200  22 11   8.6   4.7 |   2.9  37.2  175  26 13   8.1   4.5
 10750   2.3  36.1  200  22 11   9.2   5.0 |   3.4  38.1  175  26 13   7.0   3.8
 10500   3.7  38.7  195  22 11   9.7   5.3 |   3.9  39.0  170  25 13   8.1   4.5
 10250   4.4  39.9  195  22 11   9.7   5.3 |   5.2  41.4  170  24 12   8.3   4.6
 10000   5.2  41.4  190  22 11   9.9   5.4 |   5.8  42.4  170  23 12   8.7   4.8
  9750   5.9  42.6  190  22 11   9.9   5.4 |   6.4  43.5  170  22 11   9.1   5.0
  9500   6.6  43.9  190  22 11   9.9   5.4 |   7.1  44.8  170  21 11   9.1   5.0
  9250   7.4  45.3  190  22 11   9.8   5.4 |   7.8  46.0  170  20 11   8.9   4.9
  9000   8.1  46.6  190  22 11  10.3   5.6 |   8.5  47.3  170  20 10   9.7   5.3
  8750   8.9  48.0  190  22 11  10.5   5.7 |   9.2  48.6  170  19 10  10.2   5.6
  8500   9.7  49.5  190  22 11  10.1   5.6 |  10.0  50.0  170  19 10   9.8   5.4
  8250  10.4  50.7  190  21 11  10.2   5.6 |  10.7  51.3  170  19 10   9.8   5.4
  8000  11.2  52.2  190  21 11  10.8   5.9 |  11.4  52.5  170  18  9  10.4   5.7
  7750  12.2  54.0  185  21 11  16.7   9.2 |  12.3  54.1  170  17  9  12.3   6.7
  7500  13.7  56.7  185  19 10  25.0  13.7 |  13.2  55.8  170  16  8  13.4   7.4
  7250  15.3  59.5  185  18  9  10.8   5.9 |  14.1  57.4  170  14  7  12.1   6.7
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  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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