Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 151146
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0546 MDT Wednesday, April 15, 2015

This forecast is for Wednesday, April 15, 2015:

If the trigger temperature of 53.9 F/12.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 344 ft/min (1.7 m/s)
   Maximum height of thermals.................. 11255 ft MSL (4084 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7649 ft MSL (478 ft AGL)
Thermal soaring outlook for Thursday 04/16..... Good

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

Remarks...

Sunrise/Sunset.................... 06:22:49 / 19:35:02 MDT
Total possible sunshine........... 13 hr 12 min 14 sec (792 min 14 sec)
Altitude of sun at 12:59:05 MDT... 60.91 degrees

Upper air data from numerical model forecast valid on 04/15/2015 at 0600 MDT

Freezing level.................. 11274 ft MSL (4103 ft AGL)
Convective condensation level... 17077 ft MSL (9906 ft AGL)
Lifted condensation level....... 15634 ft MSL (8463 ft AGL)
Lifted index.................... +1.7
K index......................... +0.6

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  -55.7 -68.3   245   13    7   1.9   1.1      M     M       M      M    M
 45000  -52.8 -63.0   250   12    6   0.9   0.5      M     M       M      M    M
 40000  -54.6 -66.3   210   30   15  -1.2  -0.7      M     M       M      M    M
 38000  -54.8 -66.6   210   39   20   1.0   0.6      M     M       M      M    M
 36000  -54.1 -65.4   210   45   23   1.0   0.6      M     M       M      M    M
 34000  -53.2 -63.8   210   51   26   6.7   3.7      M     M       M      M    M
 32000  -49.3 -56.7   200   50   26   6.4   3.5      M     M       M      M    M
 30000  -45.4 -49.7   200   50   26   7.8   4.3   24.3  75.7     9.2      M    M
 29000  -43.1 -45.6   195   49   25   7.5   4.1   23.3  73.9     8.6      M    M
 28000  -40.9 -41.6   195   47   24   7.5   4.1   22.4  72.4     8.0      M    M
 27000  -38.6 -37.5   195   46   24   7.5   4.1   21.7  71.1     7.6      M    M
 26000  -36.3 -33.3   195   45   23   7.8   4.3   20.9  69.7     7.0      M    M
 25000  -34.0 -29.2   195   44   23   7.8   4.3   20.2  68.3     6.5      M    M
 24000  -31.1 -24.0   195   43   22   8.0   4.4   19.4  67.0     5.9      M    M
 23000  -28.5 -19.3   195   43   22   8.6   4.7   18.9  66.0     5.5      M    M
 22000  -26.0 -14.8   195   42   22   8.6   4.7   18.5  65.3     5.2      M    M
 21000  -23.4 -10.1   195   42   21   8.4   4.6   18.2  64.7     5.0      M    M
 20000  -20.9  -5.6   195   39   20   8.3   4.6   17.6  63.6     4.6      M    M
 19500  -19.7  -3.5   195   37   19   8.3   4.6   17.3  63.2     4.4      M    M
 19000  -18.4  -1.1   195   36   18   8.3   4.6   17.1  62.8     4.2      M    M
 18500  -17.2   1.0   195   34   18   8.3   4.6   16.9  62.5     4.0      M    M
 18000  -15.9   3.4   200   34   17   8.4   4.6   16.7  62.0     3.8      M    M
 17500  -14.7   5.5   200   33   17   8.4   4.6   16.5  61.6     3.7      M    M
 17000  -13.4   7.9   205   33   17   8.4   4.6   16.2  61.2     3.5      M    M
 16500  -12.2  10.0   210   33   17   8.4   4.6   16.0  60.8     3.3      M    M
 16000  -10.9  12.4   215   33   17   8.0   4.4   15.8  60.4     3.1      M    M
 15500   -9.8  14.4   215   32   16   7.8   4.3   15.4  59.8     2.8      M    M
 15000   -8.6  16.5   220   31   16   7.8   4.3   15.1  59.2     2.5      M    M
 14500   -7.4  18.7   225   31   16   8.0   4.4   14.8  58.7     2.2      M    M
 14000   -6.2  20.8   230   33   17   8.0   4.4   14.5  58.2     2.0      M    M
 13500   -5.1  22.8   235   35   18   7.2   3.9   14.2  57.5     1.7      M    M
 13000   -4.0  24.8   240   38   20   7.1   3.9   13.8  56.8     1.3      M    M
 12500   -2.9  26.8   245   40   21   8.4   4.6   13.4  56.2     1.0      M    M
 12000   -1.8  28.8   245   41   21   6.2   3.4   13.1  55.6     0.6      M    M
 11750   -1.3  29.7   250   42   21   7.1   3.9   12.8  55.1     0.4      M    M
 11500   -0.8  30.6   250   41   21   8.2   4.5   12.7  54.8     0.2      M    M
 11250   -0.2  31.6   250   40   21   8.3   4.5   12.5  54.6     0.1      M    M
 11000    0.4  32.7   250   39   20   7.8   4.3   12.4  54.4    -0.1    328  1.7
 10750    0.9  33.6   255   39   20   7.7   4.2   12.2  54.0    -0.3    305  1.5
 10500    1.5  34.7   255   37   19   8.3   4.6   12.1  53.8    -0.4    280  1.4
 10250    2.1  35.8   255   35   18   8.3   4.5   12.0  53.6    -0.6    255  1.3
 10000    2.7  36.9   255   33   17   8.4   4.6   11.9  53.4    -0.7    229  1.2
  9750    3.9  39.0   255   30   15   8.3   4.6   11.7  53.0    -1.0    178  0.9
  9500    4.5  40.1   255   28   15   8.3   4.5   11.6  52.8    -1.1    153  0.8
  9250    5.1  41.2   255   26   14   8.4   4.6   11.5  52.6    -1.2    128  0.6
  9000    5.7  42.3   255   25   13   8.3   4.6   11.4  52.4    -1.4    102  0.5
  8750    6.3  43.3   250   23   12   7.6   4.1   11.2  52.2    -1.5     77  0.4
  8500    6.8  44.2   250   21   11   7.3   4.0   11.0  51.9    -1.7     54  0.3
  8250    7.4  45.3   250   19   10   6.8   3.7   10.8  51.5    -1.9     32  0.2
  8000    7.8  46.0   250   16    8   4.3   2.3   10.5  51.0    -2.3     12  0.1
  7750    7.8  46.0   245   14    7  -3.5  -1.9    9.9  49.8    -2.9      2  0.0
  7500    7.2  45.0   245    9    5 -12.4  -6.8    8.5  47.4    -4.3     14  0.1
  7250    6.5  43.7   240    4    2   2.5   1.4    7.2  44.9    -5.7     27  0.1
  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 * * * * * *

           04/15/2015 at 0900 MDT          |       04/15/2015 at 1200 MDT
                                           |
K index... -25.1  LI... +274.2             | K index... -13.9  LI... +276.0
CAPE... 0.0  CIN... -1.2                   | CAPE... 0.0  CIN... -1.0
                                           |
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 -55.4 -67.7  255  10  5   2.1   1.1 | -55.4 -67.7  235   9  5   2.7   1.5
 45000 -52.3 -62.1  250  13  7   1.7   0.9 | -51.4 -60.5  250  14  7   2.4   1.3
 40000 -51.3 -60.3  220  22 12   0.6   0.3 | -49.1 -56.4  245  18  9   1.4   0.8
 38000 -51.3 -60.3  215  31 16  -0.8  -0.4 | -49.2 -56.6  235  24 12  -2.3  -1.3
 36000 -51.8 -61.2  210  45 23  -0.8  -0.4 | -50.5 -58.9  225  39 20  -2.3  -1.3
 34000 -52.2 -62.0  210  58 30   3.4   1.9 | -51.9 -61.4  220  54 28   1.5   0.8
 32000 -49.2 -56.6  205  62 32   4.9   2.7 | -49.2 -56.6  215  59 30   4.6   2.5
 30000 -46.2 -51.2  200  64 33   6.4   3.5 | -46.4 -51.5  215  64 33   5.3   2.9
 29000 -44.2 -47.6  200  63 33   6.7   3.7 | -44.7 -48.5  215  61 31   5.7   3.1
 28000 -42.2 -44.0  195  62 32   6.7   3.7 | -43.0 -45.4  210  57 29   5.7   3.1
 27000 -40.1 -40.2  195  61 31   6.7   3.7 | -41.3 -42.3  210  54 28   5.6   3.1
 26000 -37.9 -36.2  190  60 31   7.9   4.3 | -39.1 -38.4  210  51 26   8.4   4.6
 25000 -35.5 -31.9  195  58 30   7.9   4.3 | -36.0 -32.8  205  48 25   8.4   4.6
 24000 -32.6 -26.7  195  56 29   7.9   4.3 | -33.5 -28.3  205  46 24   8.4   4.6
 23000 -30.1 -22.2  195  54 28   8.3   4.5 | -30.9 -23.6  205  44 23   8.5   4.7
 22000 -27.6 -17.7  200  51 26   8.3   4.5 | -28.4 -19.1  205  43 22   8.5   4.7
 21000 -25.1 -13.2  205  49 25   8.2   4.5 | -25.8 -14.4  205  42 22   8.6   4.7
 20000 -22.7  -8.9  205  46 24   8.2   4.5 | -23.2  -9.8  205  41 21   8.8   4.8
 19500 -21.5  -6.7  210  45 23   8.2   4.5 | -21.9  -7.4  210  40 21   8.8   4.8
 19000 -20.3  -4.5  210  44 23   8.2   4.5 | -20.6  -5.1  210  39 20   8.8   4.8
 18500 -19.0  -2.2  215  43 22   8.6   4.7 | -19.2  -2.6  210  39 20   8.6   4.7
 18000 -17.6   0.3  215  42 22   9.8   5.4 | -18.0  -0.4  215  37 19   7.9   4.3
 17500 -16.1   3.0  215  41 21   9.8   5.4 | -16.8   1.8  220  36 19   7.9   4.3
 17000 -14.7   5.5  215  39 20   9.6   5.3 | -15.6   3.9  225  35 18   8.4   4.6
 16500 -13.3   8.1  215  38 20   9.6   5.3 | -14.4   6.1  225  34 18   8.4   4.6
 16000 -11.8  10.8  215  37 19   9.1   5.0 | -13.1   8.4  225  33 17   7.9   4.3
 15500 -10.5  13.1  215  36 18   8.7   4.8 | -12.0  10.4  230  35 18   7.3   4.0
 15000  -9.2  15.4  220  35 18   8.4   4.6 | -10.9  12.4  235  37 19   7.2   3.9
 14500  -8.1  17.4  225  35 18   7.1   3.9 |  -9.9  14.2  235  37 19   6.9   3.8
 14000  -7.0  19.4  230  36 19   7.2   4.0 |  -8.8  16.2  240  37 19   7.0   3.8
 13500  -6.0  21.2  235  38 20   6.6   3.6 |  -7.8  18.0  240  36 18   7.4   4.1
 13000  -5.0  23.0  240  41 21   6.6   3.6 |  -6.7  19.9  235  33 17   7.4   4.0
 12500  -4.0  24.8  245  43 22   7.7   4.2 |  -5.6  21.9  230  30 16   8.6   4.7
 12000  -2.9  26.8  245  43 22   6.2   3.4 |  -4.3  24.3  225  28 14   8.6   4.7
 11750  -2.5  27.5  250  43 22   6.4   3.5 |  -3.7  25.3  225  27 14   9.1   5.0
 11500  -2.0  28.4  250  42 21   6.9   3.8 |  -3.0  26.6  220  27 14   9.8   5.4
 11250  -1.5  29.3  245  39 20   6.8   3.7 |  -2.2  28.0  220  26 13  10.0   5.5
 11000  -1.0  30.2  245  37 19   7.4   4.1 |  -1.5  29.3  220  26 13   9.4   5.2
 10750  -0.5  31.1  245  35 18   7.9   4.3 |  -0.8  30.6  215  26 13   9.2   5.0
 10500   0.1  32.2  245  33 17   7.6   4.1 |  -0.1  31.8  215  26 13   9.7   5.3
 10250   0.6  33.1  245  31 16   7.5   4.1 |   0.6  33.1  215  25 13   9.7   5.3
 10000   1.2  34.2  245  28 15   7.7   4.2 |   2.1  35.8  215  25 13  10.3   5.7
  9750   2.4  36.3  240  25 13   9.1   5.0 |   2.9  37.2  215  25 13  10.2   5.6
  9500   3.1  37.6  240  23 12   8.5   4.6 |   3.6  38.5  215  25 13  10.0   5.5
  9250   3.7  38.7  235  21 11   8.7   4.8 |   4.4  39.9  210  25 13  10.1   5.5
  9000   4.3  39.7  235  19 10   7.9   4.3 |   5.1  41.2  210  25 13   9.9   5.4
  8750   4.9  40.8  230  18  9   8.2   4.5 |   5.9  42.6  210  25 13  10.2   5.6
  8500   5.5  41.9  225  16  8   9.2   5.0 |   6.7  44.1  210  24 13  10.4   5.7
  8250   6.2  43.2  220  14  7   8.7   4.8 |   7.4  45.3  210  24 12  10.6   5.8
  8000   6.7  44.1  215  13  7   7.2   3.9 |   8.2  46.8  210  24 12  11.6   6.4
  7750   7.3  45.1  205  12  6  10.8   5.9 |   9.3  48.7  205  23 12  18.7  10.3
  7500   8.4  47.1  200  11  5  19.4  10.6 |  11.1  52.0  205  21 11  29.0  15.9
  7250   9.5  49.1  190  10  5   3.5   1.9 |  12.9  55.2  205  19 10  11.2   6.2
  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

           04/15/2015 at 1500 MDT          |       04/15/2015 at 1800 MDT
                                           |
K index... -13.0  LI... +274.7             | K index... -12.5  LI... +274.5
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 -55.9 -68.6  235  12  6   2.8   1.5 | -55.7 -68.3  235  11  6   2.8   1.5
 45000 -51.7 -61.1  245  12  6   3.1   1.7 | -51.5 -60.7  230  12  6   3.1   1.7
 40000 -45.9 -50.6  250  13  7   3.7   2.0 | -45.5 -49.9  305   8  4   3.8   2.1
 38000 -45.8 -50.4  235  19 10  -5.1  -2.8 | -45.4 -49.7  270  10  5  -4.9  -2.7
 36000 -48.9 -56.0  225  36 18  -5.1  -2.8 | -48.3 -54.9  230  27 14  -4.9  -2.7
 34000 -51.9 -61.4  220  53 27  -1.8  -1.0 | -51.3 -60.3  220  46 24  -2.1  -1.2
 32000 -50.1 -58.2  220  60 31   3.2   1.7 | -49.5 -57.1  220  49 25   3.3   1.8
 30000 -48.2 -54.8  220  67 34   5.3   2.9 | -47.5 -53.5  215  51 26   4.5   2.5
 29000 -46.1 -51.0  220  65 33   7.2   3.9 | -45.7 -50.3  215  53 27   6.0   3.3
 28000 -43.9 -47.0  215  63 32   7.2   3.9 | -43.9 -47.0  215  55 28   6.0   3.3
 27000 -41.8 -43.2  215  61 32   7.1   3.9 | -42.1 -43.8  215  57 29   6.0   3.3
 26000 -39.4 -38.9  215  60 31   8.3   4.6 | -39.3 -38.7  215  58 30   8.7   4.7
 25000 -36.3 -33.3  215  59 30   8.4   4.6 | -36.7 -34.1  215  59 30   8.6   4.7
 24000 -33.8 -28.8  215  58 30   8.3   4.6 | -34.1 -29.4  215  59 30   8.8   4.8
 23000 -31.2 -24.2  215  54 28   8.6   4.7 | -31.7 -25.1  215  55 29   7.6   4.2
 22000 -28.6 -19.5  215  50 26   8.6   4.7 | -29.4 -20.9  220  51 26   7.6   4.2
 21000 -26.1 -15.0  215  46 24   8.2   4.5 | -27.1 -16.8  225  46 24   7.7   4.2
 20000 -23.8 -10.8  220  43 22   7.7   4.2 | -24.8 -12.6  230  44 23   7.9   4.3
 19500 -22.6  -8.7  225  41 21   7.7   4.2 | -23.6 -10.5  230  43 22   7.9   4.3
 19000 -21.5  -6.7  230  40 21   7.7   4.2 | -22.4  -8.3  235  43 22   7.9   4.3
 18500 -20.3  -4.5  230  40 20   7.9   4.3 | -21.2  -6.2  240  42 22   8.0   4.4
 18000 -19.0  -2.2  235  39 20   8.6   4.7 | -20.0  -4.0  240  42 21   8.4   4.6
 17500 -17.8  -0.0  235  38 19   8.6   4.7 | -18.7  -1.7  245  41 21   8.4   4.6
 17000 -16.5   2.3  235  37 19   8.2   4.5 | -17.4   0.7  245  39 20   8.7   4.8
 16500 -15.3   4.5  235  36 18   8.2   4.5 | -16.1   3.0  245  37 19   8.8   4.8
 16000 -14.0   6.8  235  35 18   8.4   4.6 | -14.8   5.4  245  35 18   8.9   4.9
 15500 -12.8   9.0  235  34 17   8.5   4.7 | -13.5   7.7  245  33 17   9.0   4.9
 15000 -11.5  11.3  230  33 17   8.6   4.7 | -12.1  10.2  245  31 16   9.0   4.9
 14500 -10.2  13.6  230  32 16   8.6   4.7 | -10.8  12.6  245  29 15   8.9   4.9
 14000  -8.9  16.0  230  31 16   8.7   4.7 |  -9.5  14.9  240  27 14   8.9   4.9
 13500  -7.6  18.3  225  29 15   8.7   4.8 |  -8.2  17.2  235  26 13   8.8   4.8
 13000  -6.4  20.5  220  27 14   8.6   4.7 |  -6.9  19.6  230  25 13   8.8   4.8
 12500  -5.0  23.0  220  25 13  10.4   5.7 |  -5.5  22.1  230  25 13   9.3   5.1
 12000  -3.5  25.7  215  24 12   8.3   4.6 |  -4.2  24.4  225  25 13   7.5   4.1
 11750  -2.9  26.8  215  24 12   8.9   4.9 |  -3.7  25.3  220  25 13   7.8   4.3
 11500  -2.2  28.0  210  24 12   9.9   5.4 |  -3.0  26.6  220  25 13   8.8   4.8
 11250  -1.5  29.3  210  24 12   9.9   5.5 |  -2.4  27.7  215  25 13   8.6   4.7
 11000  -0.7  30.7  210  24 12   9.7   5.3 |  -1.8  28.8  215  25 13   9.2   5.0
 10750  -0.0  32.0  210  24 12   9.5   5.2 |  -1.0  30.2  215  25 13   9.7   5.3
 10500   0.7  33.3  210  24 12   9.9   5.4 |  -0.3  31.5  210  25 13   9.5   5.2
 10250   1.5  34.7  210  24 12   9.8   5.4 |   0.4  32.7  210  25 13   9.4   5.2
 10000   3.0  37.4  210  24 12  10.6   5.8 |   1.8  35.2  210  25 13  10.0   5.5
  9750   3.8  38.8  205  24 12  10.2   5.6 |   2.6  36.7  210  25 13   9.8   5.4
  9500   4.5  40.1  205  24 12   9.9   5.4 |   3.3  37.9  210  25 13   9.7   5.3
  9250   5.2  41.4  205  24 12   9.9   5.5 |   4.0  39.2  210  25 13   9.7   5.3
  9000   6.0  42.8  205  24 12   9.6   5.3 |   4.8  40.6  210  25 13   9.9   5.4
  8750   6.7  44.1  205  23 12  10.2   5.6 |   5.5  41.9  205  24 13  10.2   5.6
  8500   7.5  45.5  205  23 12  10.8   5.9 |   6.3  43.3  205  24 13  10.1   5.6
  8250   8.3  46.9  205  23 12  10.7   5.9 |   7.0  44.6  205  24 12  10.2   5.6
  8000   9.1  48.4  205  23 12  11.2   6.1 |   7.8  46.0  205  24 12  10.3   5.6
  7750  10.1  50.2  200  22 11  18.1   9.9 |   8.6  47.5  205  23 12  13.0   7.1
  7500  11.9  53.4  200  20 11  28.8  15.8 |   9.8  49.6  205  20 11  17.4   9.6
  7250  13.7  56.7  200  19 10  10.0   5.5 |  10.9  51.6  200  18  9   9.5   5.2
  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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