Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 251155
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0555 MDT Wednesday, May 25, 2016

This forecast is for Wednesday, May 25, 2016:

If the trigger temperature of 58.9 F/14.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 971 ft/min (4.9 m/s)
   Maximum height of thermals.................. 17512 ft MSL (10754 ft AGL)

Forecast maximum temperature................... 69.0 F/21.0 C
Time of trigger temperature.................... 1000 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12579 ft MSL (5821 ft AGL)
Thermal soaring outlook for Thursday 05/26..... Good

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

Remarks...

Sunrise/Sunset.................... 05:38:45 / 20:13:07 MDT
Total possible sunshine........... 14 hr 34 min 22 sec (874 min 22 sec)
Altitude of sun at 12:56:07 MDT... 72.16 degrees

Upper air data from numerical model forecast valid on 05/25/2016 at 0600 MDT

Freezing level.................. 13198 ft MSL (6440 ft AGL)
Convective condensation level... 19811 ft MSL (13053 ft AGL)
Lifted condensation level....... 19150 ft MSL (12392 ft AGL)
Lifted index.................... -1.1
K index......................... -27.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -56.3 -69.3   235   34   18   1.0   0.5      M     M       M      M    M
 45000  -54.8 -66.6   225   56   29   1.3   0.7      M     M       M      M    M
 40000  -52.8 -63.0   225   67   34   1.3   0.7      M     M       M      M    M
 38000  -52.1 -61.8   225   65   33   1.1   0.6      M     M       M      M    M
 36000  -51.5 -60.7   230   61   31   1.1   0.6      M     M       M      M    M
 34000  -49.9 -57.8   230   57   29   5.6   3.1      M     M       M      M    M
 32000  -46.6 -51.9   230   53   28   5.6   3.1      M     M       M      M    M
 30000  -42.8 -45.0   230   50   26   7.7   4.2   26.8  80.3     4.8      M    M
 29000  -39.9 -39.8   235   48   25   7.7   4.2   25.8  78.4     4.1      M    M
 28000  -37.6 -35.7   235   47   24   7.7   4.2   25.1  77.1     3.6      M    M
 27000  -35.3 -31.5   235   45   23   8.2   4.5   24.4  75.9     3.1      M    M
 26000  -32.8 -27.0   235   43   22   8.2   4.5   23.7  74.7     2.6      M    M
 25000  -30.4 -22.7   230   41   21   8.2   4.5   23.2  73.8     2.1      M    M
 24000  -27.8 -18.0   225   39   20   9.4   5.2   22.8  73.1     1.8      M    M
 23000  -25.1 -13.2   220   39   20   9.3   5.1   22.6  72.6     1.6      M    M
 22000  -22.3  -8.1   215   39   20   9.3   5.1   22.4  72.4     1.6      M    M
 21000  -19.6  -3.3   215   38   20   8.5   4.6   22.2  72.0     1.4      M    M
 20000  -17.0   1.4   220   36   19   8.5   4.7   21.7  71.1     1.0      M    M
 19500  -15.7   3.7   220   35   18   8.5   4.7   21.5  70.8     0.8      M    M
 19000  -14.5   5.9   220   34   18   8.6   4.7   21.4  70.5     0.7      M    M
 18500  -13.2   8.2   225   33   17   8.1   4.4   21.1  70.1     0.5      M    M
 18000  -12.0  10.4   230   33   17   8.1   4.5   20.9  69.6     0.3      M    M
 17500  -10.8  12.6   235   32   17   8.2   4.5   20.6  69.1     0.0      M    M
 17000   -9.5  14.9   240   33   17   8.2   4.5   20.3  68.6    -0.2    926  4.7
 16500   -8.3  17.1   240   34   17   8.2   4.5   20.1  68.1    -0.5    874  4.4
 16000   -7.1  19.2   245   34   17   8.2   4.5   19.8  67.7    -0.7    823  4.2
 15500   -5.9  21.4   245   34   17   8.2   4.5   19.6  67.2    -0.9    771  3.9
 15000   -4.6  23.7   245   34   17   8.2   4.5   19.3  66.7    -1.2    720  3.7
 14500   -2.8  27.0   250   34   17   8.2   4.5   18.9  66.0    -1.5    642  3.3
 14000   -1.6  29.1   250   32   17   7.6   4.2   18.6  65.5    -1.8    592  3.0
 13500   -0.5  31.1   250   30   16   7.8   4.3   18.3  64.9    -2.1    543  2.8
 13000    0.6  33.1   255   29   15   5.8   3.2   17.8  64.1    -2.6    497  2.5
 12500    1.4  34.5   255   28   15   5.8   3.2   17.2  62.9    -3.2    457  2.3
 12000    2.3  36.1   260   27   14   5.9   3.3   16.6  61.8    -3.9    417  2.1
 11750    2.7  36.9   265   27   14   6.0   3.3   16.3  61.3    -4.2    397  2.0
 11500    3.1  37.6   265   27   14   6.2   3.4   16.0  60.7    -4.5    376  1.9
 11250    3.6  38.5   270   28   14   5.8   3.2   15.7  60.2    -4.8    356  1.8
 11000    3.9  39.0   275   28   14   5.8   3.2   15.4  59.7    -5.2    337  1.7
 10750    4.4  39.9   275   28   15   6.2   3.4   15.1  59.1    -5.5    317  1.6
 10500    4.8  40.6   280   29   15   6.3   3.4   14.8  58.6    -5.8    297  1.5
 10250    5.2  41.4   285   30   15   6.0   3.3   14.5  58.2    -6.1    277  1.4
 10000    5.7  42.3   285   30   16   7.3   4.0   14.3  57.7    -6.4    256  1.3
  9750    6.3  43.3   290   30   15   8.8   4.8   14.2  57.5    -6.6    231  1.2
  9500    6.9  44.4   290   30   15   8.9   4.9   14.1  57.3    -6.7    205  1.0
  9250    7.5  45.5   295   29   15   8.5   4.7   14.0  57.2    -6.8    179  0.9
  9000    8.1  46.6   295   29   15   7.9   4.3   13.9  57.0    -7.0    154  0.8
  8750    8.6  47.5   295   28   15   6.5   3.6   13.7  56.7    -7.2    130  0.7
  8500    9.1  48.4   295   27   14   6.4   3.5   13.4  56.2    -7.5    110  0.6
  8250    9.5  49.1   295   27   14   4.2   2.3   13.1  55.7    -7.8     89  0.5
  8000    9.7  49.5   300   24   13   0.6   0.3   12.6  54.6    -8.4     77  0.4
  7750    9.8  49.6   300   22   11   4.5   2.5   12.0  53.5    -9.0     66  0.3
  7500   10.2  50.4   300   18    9   4.1   2.3   11.7  53.0    -9.4     46  0.2
  7250   10.0  50.0   300   14    7 -13.1  -7.2   10.9  51.6   -10.2     46  0.2
  7000    8.2  46.8   300   11    6 -30.6 -16.8    8.9  48.1   -12.1     91  0.5
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           05/25/2016 at 0900 MDT          |       05/25/2016 at 1200 MDT
                                           |
K index... -20.3  LI... +275.6             | K index... -0.5  LI... +274.6
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 -55.4 -67.7  230  31 16   2.4   1.3 | -55.0 -67.0  230  32 16   3.1   1.7
 45000 -52.3 -62.1  230  54 28  -1.3  -0.7 | -51.1 -60.0  240  49 25  -2.7  -1.5
 40000 -54.4 -65.9  235  68 35  -1.4  -0.8 | -55.4 -67.7  245  71 37  -2.7  -1.5
 38000 -53.9 -65.0  240  69 36   1.8   1.0 | -54.7 -66.5  245  74 38   2.9   1.6
 36000 -52.9 -63.2  240  69 35   1.8   1.0 | -53.0 -63.4  245  75 39   2.9   1.6
 34000 -50.8 -59.4  240  68 35   7.0   3.8 | -50.4 -58.7  245  74 38   6.9   3.8
 32000 -46.6 -51.9  240  64 33   7.1   3.9 | -46.3 -51.3  245  70 36   6.9   3.8
 30000 -41.9 -43.4  240  59 30   6.8   3.7 | -41.2 -42.2  245  66 34   8.5   4.7
 29000 -39.8 -39.6  240  56 29   6.8   3.7 | -38.7 -37.7  245  64 33   8.5   4.7
 28000 -37.8 -36.0  235  52 27   6.8   3.7 | -36.1 -33.0  245  62 32   8.5   4.7
 27000 -35.6 -32.1  235  50 26   8.6   4.7 | -33.7 -28.7  240  60 31   7.0   3.8
 26000 -33.1 -27.6  230  48 25   8.5   4.7 | -31.6 -24.9  240  56 29   7.0   3.9
 25000 -30.5 -22.9  225  46 24   8.5   4.7 | -29.5 -21.1  240  52 27   7.0   3.9
 24000 -28.0 -18.4  225  45 23   9.1   5.0 | -27.4 -17.3  240  49 25   7.0   3.9
 23000 -25.2 -13.4  220  42 22   9.1   5.0 | -25.3 -13.5  235  44 23   7.1   3.9
 22000 -22.5  -8.5  220  39 20   9.0   5.0 | -23.2  -9.8  235  40 21   7.1   3.9
 21000 -19.9  -3.8  220  36 19   7.7   4.2 | -21.0  -5.8  235  37 19   7.7   4.2
 20000 -17.6   0.3  225  33 17   7.8   4.3 | -18.7  -1.7  240  37 19   7.6   4.2
 19500 -16.4   2.5  230  31 16   7.8   4.3 | -17.6   0.3  245  37 19   7.6   4.2
 19000 -15.3   4.5  235  30 15   7.7   4.2 | -16.4   2.5  250  38 19   7.6   4.2
 18500 -14.1   6.6  240  30 15   8.3   4.5 | -15.3   4.5  255  38 20   7.7   4.2
 18000 -12.8   9.0  245  30 16   8.2   4.5 | -14.1   6.6  255  38 19   7.7   4.2
 17500 -11.6  11.1  250  31 16   8.2   4.5 | -13.0   8.6  255  38 19   7.6   4.2
 17000 -10.4  13.3  255  31 16   8.2   4.5 | -11.8  10.8  260  36 19   7.6   4.2
 16500  -9.1  15.6  255  32 16   8.2   4.5 | -10.7  12.7  260  35 18   7.7   4.2
 16000  -8.0  17.6  255  31 16   7.6   4.2 |  -9.6  14.7  265  33 17   7.7   4.2
 15500  -6.8  19.8  255  30 15   7.6   4.2 |  -8.5  16.7  265  30 15   7.7   4.2
 15000  -5.7  21.7  255  29 15   7.5   4.1 |  -6.6  20.1  265  25 13   8.9   4.9
 14500  -4.0  24.8  260  29 15   7.4   4.1 |  -5.3  22.5  265  21 11   8.9   4.9
 14000  -2.8  27.0  260  27 14   8.0   4.4 |  -4.0  24.8  260  18  9   9.3   5.1
 13500  -1.6  29.1  260  25 13   8.1   4.5 |  -2.6  27.3  260  15  8   9.2   5.0
 13000  -0.5  31.1  265  24 13   6.4   3.5 |  -1.2  29.8  255  13  7  10.0   5.5
 12500   0.4  32.7  270  28 14   6.2   3.4 |   0.3  32.5  250  12  6   9.3   5.1
 12000   1.1  34.0  275  31 16   3.8   2.1 |   1.6  34.9  245  11  5   9.4   5.2
 11750   1.4  34.5  275  31 16   4.4   2.4 |   2.3  36.1  245  10  5   9.5   5.2
 11500   1.7  35.1  280  30 16   4.2   2.3 |   3.0  37.4  240  10  5   9.6   5.2
 11250   2.0  35.6  280  30 15   5.4   3.0 |   3.7  38.7  240   9  5   9.3   5.1
 11000   2.4  36.3  285  27 14   6.6   3.6 |   4.4  39.9  235   9  5   9.6   5.3
 10750   2.8  37.0  285  25 13   6.4   3.5 |   5.2  41.4  235   9  5   9.9   5.5
 10500   3.3  37.9  290  22 11   6.8   3.7 |   5.9  42.6  235   9  5  10.3   5.7
 10250   3.7  38.7  290  20 10   6.1   3.3 |   6.7  44.1  230   9  5   8.5   4.7
 10000   4.2  39.6  295  18  9   7.6   4.2 |   7.2  45.0  230   9  4   8.7   4.8
  9750   4.9  40.8  295  16  8  10.1   5.5 |   8.0  46.4  230   9  4  10.9   6.0
  9500   5.6  42.1  300  14  7  10.4   5.7 |   8.8  47.8  225   8  4  10.8   5.9
  9250   6.3  43.3  305  12  6   9.4   5.2 |   9.6  49.3  225   8  4  10.1   5.5
  9000   7.0  44.6  305  11  6   8.4   4.6 |  10.3  50.5  225   8  4   9.3   5.1
  8750   7.6  45.7  305  10  5   9.8   5.4 |  11.0  51.8  220   8  4  10.4   5.7
  8500   8.4  47.1  310   9  5  10.7   5.9 |  11.8  53.2  220   8  4  10.9   6.0
  8250   9.2  48.6  310   8  4  10.3   5.7 |  12.6  54.7  220   8  4  10.5   5.7
  8000   9.9  49.8  310   7  4  10.6   5.8 |  13.4  56.1  215   8  4  10.7   5.9
  7750  10.7  51.3  310   7  4   9.4   5.2 |  14.2  57.6  215   8  4   9.6   5.3
  7500  11.4  52.5  315   6  3   8.6   4.7 |  14.9  58.8  210   7  4  10.2   5.6
  7250  12.0  53.6  315   6  3  10.0   5.5 |  15.8  60.4  210   7  4  14.1   7.7
  7000  12.8  55.0  315   6  3  10.3   5.7 |  16.9  62.4  210   7  3  15.5   8.5
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/25/2016 at 1500 MDT          |       05/25/2016 at 1800 MDT
                                           |
K index... +11.4  LI... +273.1             | K index... +14.6  LI... +272.8
CAPE... +3.1  CIN... -7.2                  | CAPE... +51.7  CIN... -25.0
                                           |
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 -54.5 -66.1  220  30 16   2.9   1.6 | -55.5 -67.9  220  26 13   2.6   1.4
 45000 -51.0 -59.8  240  37 19  -2.7  -1.5 | -52.3 -62.1  240  30 16  -2.1  -1.2
 40000 -55.2 -67.4  245  72 37  -2.8  -1.5 | -55.6 -68.1  245  68 35  -2.1  -1.1
 38000 -54.6 -66.3  245  78 40   2.8   1.5 | -54.6 -66.3  245  75 39   3.1   1.7
 36000 -53.0 -63.4  245  81 42   2.8   1.5 | -52.8 -63.0  245  78 40   3.1   1.7
 34000 -50.6 -59.1  245  82 42   6.4   3.5 | -50.3 -58.5  245  79 40   6.2   3.4
 32000 -46.7 -52.1  245  77 40   6.5   3.6 | -46.6 -51.9  245  73 38   6.2   3.4
 30000 -41.9 -43.4  245  71 37   8.3   4.6 | -41.9 -43.4  245  67 35   8.0   4.4
 29000 -39.4 -38.9  245  69 35   8.3   4.6 | -39.5 -39.1  245  65 33   8.0   4.4
 28000 -36.9 -34.4  245  66 34   8.3   4.6 | -37.1 -34.8  245  62 32   8.0   4.4
 27000 -34.5 -30.1  245  64 33   6.8   3.7 | -34.9 -30.8  245  59 30   6.8   3.7
 26000 -32.5 -26.5  245  61 31   6.9   3.8 | -32.8 -27.0  245  55 28   6.9   3.8
 25000 -30.4 -22.7  245  58 30   6.8   3.8 | -30.8 -23.4  245  52 27   6.9   3.8
 24000 -28.3 -18.9  245  55 28   7.7   4.2 | -28.6 -19.5  250  47 24   8.3   4.6
 23000 -26.1 -15.0  250  49 25   7.6   4.2 | -26.2 -15.2  250  40 21   8.2   4.5
 22000 -23.8 -10.8  250  44 23   7.6   4.2 | -23.8 -10.8  250  33 17   8.2   4.5
 21000 -21.4  -6.5  250  38 20   8.2   4.5 | -21.3  -6.3  255  27 14   8.6   4.7
 20000 -19.0  -2.2  255  34 17   8.2   4.5 | -18.8  -1.8  255  23 12   8.6   4.7
 19500 -17.8  -0.0  260  31 16   8.2   4.5 | -17.5   0.5  260  21 11   8.6   4.7
 19000 -16.5   2.3  265  29 15   8.2   4.5 | -16.2   2.8  260  19 10   8.7   4.8
 18500 -15.3   4.5  265  27 14   9.0   4.9 | -14.8   5.4  260  18  9   9.9   5.4
 18000 -14.0   6.8  265  24 12   9.0   4.9 | -13.4   7.9  260  18  9   9.8   5.4
 17500 -12.7   9.1  265  22 11   9.3   5.1 | -11.9  10.6  260  17  9   9.9   5.5
 17000 -11.2  11.8  265  21 11   9.4   5.2 | -10.4  13.3  260  17  9  10.0   5.5
 16500  -9.8  14.4  265  20 10   9.5   5.2 |  -8.9  16.0  260  16  8   9.9   5.4
 16000  -8.4  16.9  265  19 10   9.8   5.4 |  -7.5  18.5  260  16  8   9.4   5.2
 15500  -6.9  19.6  265  18  9   9.9   5.4 |  -6.1  21.0  260  15  8   9.4   5.2
 15000  -4.8  23.4  260  17  9   9.4   5.2 |  -4.6  23.7  260  14  7   9.6   5.3
 14500  -3.4  25.9  260  16  8   9.5   5.2 |  -2.5  27.5  255  14  7   9.6   5.2
 14000  -1.9  28.6  255  15  8   9.8   5.4 |  -1.1  30.0  255  13  7   9.5   5.2
 13500  -0.5  31.1  255  14  7   9.8   5.4 |   0.3  32.5  250  13  7   9.6   5.2
 13000   1.0  33.8  250  13  7   9.5   5.2 |   1.7  35.1  250  12  6   8.9   4.9
 12500   2.4  36.3  240  13  7   9.3   5.1 |   3.0  37.4  245  12  6   9.9   5.4
 12000   3.8  38.8  240  12  6   9.8   5.4 |   4.5  40.1  240  12  6   8.4   4.6
 11750   4.5  40.1  235  12  6   9.7   5.3 |   5.1  41.2  240  12  6   8.7   4.8
 11500   5.3  41.5  235  12  6   9.8   5.3 |   5.8  42.4  235  11  6   8.1   4.4
 11250   6.0  42.8  235  12  6   9.7   5.3 |   6.4  43.5  230  11  6  10.3   5.7
 11000   6.7  44.1  230  12  6   9.7   5.3 |   7.3  45.1  230  11  6  10.7   5.9
 10750   7.5  45.5  230  12  6   9.7   5.3 |   7.9  46.2  225  11  6   8.6   4.7
 10500   8.2  46.8  230  11  6  10.0   5.5 |   8.6  47.5  220  11  6   9.7   5.3
 10250   8.9  48.0  225  11  6   8.9   4.9 |   9.3  48.7  215  11  6   7.2   3.9
 10000   9.6  49.3  225  11  6   9.3   5.1 |   9.8  49.6  210  12  6   8.0   4.4
  9750  10.3  50.5  225  11  6  10.7   5.9 |  10.5  50.9  210  11  6  10.9   6.0
  9500  11.1  52.0  225  11  6  10.5   5.8 |  11.3  52.3  205  11  6  10.3   5.7
  9250  11.9  53.4  220  11  6  10.0   5.5 |  12.1  53.8  205  11  6   9.9   5.4
  9000  12.6  54.7  220  11  6   9.6   5.2 |  12.8  55.0  205  12  6   9.4   5.1
  8750  13.4  56.1  220  11  6  10.4   5.7 |  13.5  56.3  200  12  6  10.3   5.7
  8500  14.2  57.6  220  11  6  10.8   5.9 |  14.3  57.7  200  12  6  10.9   6.0
  8250  14.9  58.8  215  11  5  10.4   5.7 |  15.1  59.2  200  12  6  10.1   5.5
  8000  15.7  60.3  215  11  5  10.6   5.8 |  15.8  60.4  195  11  6   9.7   5.3
  7750  16.5  61.7  215  10  5   9.5   5.2 |  16.5  61.7  195  11  6   9.1   5.0
  7500  17.2  63.0  210  10  5   9.5   5.2 |  17.2  63.0  190  11  6   8.1   4.4
  7250  18.0  64.4  210  10  5  13.2   7.2 |  17.8  64.0  190  11  6   8.2   4.5
  7000  19.1  66.4  210  10  5  15.8   8.7 |  18.3  64.9  195  10  5   8.0   4.4
  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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