Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 031025
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0425 MDT Tuesday, May 3, 2016

This forecast is for Tuesday, May 3, 2016:

If the trigger temperature of 45.8 F/7.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 750 ft/min (3.8 m/s)
   Maximum height of thermals.................. 15419 ft MSL (8661 ft AGL)

Forecast maximum temperature................... 54.0 F/12.7 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12205 ft MSL (5448 ft AGL)
Thermal soaring outlook for Wednesday 05/04.... Excellent

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

Remarks...

Sunrise/Sunset.................... 05:58:12 / 19:53:14 MDT
Total possible sunshine........... 13 hr 55 min 3 sec (835 min 3 sec)
Altitude of sun at 12:55:53 MDT... 67.01 degrees

Upper air data from numerical model forecast valid on 05/03/2016 at 0600 MDT

Freezing level.................. 9425 ft MSL (2667 ft AGL)
Convective condensation level... 11908 ft MSL (5150 ft AGL)
Lifted condensation level....... 12934 ft MSL (6177 ft AGL)
Lifted index.................... -0.0
K index......................... +1.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -57.2 -71.0   290   30   16   1.5   0.8      M     M       M      M    M
 45000  -55.0 -67.0   295   36   19   0.2   0.1      M     M       M      M    M
 40000  -58.0 -72.4   325   38   20  -1.9  -1.1      M     M       M      M    M
 38000  -57.2 -71.0   335   38   19   3.9   2.2      M     M       M      M    M
 36000  -54.8 -66.6   355   37   19   4.0   2.2      M     M       M      M    M
 34000  -52.3 -62.1   010   40   21   5.5   3.0      M     M       M      M    M
 32000  -49.1 -56.4   010   46   24   5.4   3.0      M     M       M      M    M
 30000  -45.5 -49.9   015   51   26   8.0   4.4   24.8  76.6     9.6      M    M
 29000  -42.6 -44.7   015   54   28   7.9   4.3   23.7  74.7     9.0      M    M
 28000  -40.2 -40.4   010   56   29   7.9   4.3   23.1  73.6     8.6      M    M
 27000  -37.8 -36.0   010   58   30   8.5   4.6   22.5  72.6     8.2      M    M
 26000  -35.2 -31.4   010   57   29   8.5   4.7   22.0  71.5     7.9      M    M
 25000  -32.7 -26.9   010   57   29   8.5   4.7   21.5  70.7     7.6      M    M
 24000  -30.2 -22.4   010   56   29   8.3   4.6   21.2  70.1     7.4      M    M
 23000  -27.7 -17.9   010   53   27   8.2   4.5   20.5  68.9     6.9      M    M
 22000  -25.2 -13.4   010   50   26   8.2   4.5   20.0  68.0     6.6      M    M
 21000  -22.9  -9.2   005   47   24   6.1   3.4   19.3  66.8     6.1      M    M
 20000  -21.1  -6.0   360   44   23   6.2   3.4   18.0  64.5     5.0      M    M
 19500  -20.1  -4.2   355   43   22   6.2   3.4   17.4  63.4     4.5      M    M
 19000  -19.2  -2.6   350   42   21   6.2   3.4   16.9  62.4     4.1      M    M
 18500  -18.2  -0.8   345   41   21   7.6   4.2   16.4  61.5     3.6      M    M
 18000  -17.0   1.4   345   41   21   7.8   4.3   16.1  60.9     3.4      M    M
 17500  -15.8   3.6   345   41   21   7.3   4.0   15.8  60.4     3.1      M    M
 17000  -15.0   5.0   345   40   21   5.2   2.8   15.1  59.2     2.5      M    M
 16500  -14.2   6.4   345   40   20   5.3   2.9   14.3  57.8     1.9      M    M
 16000  -13.5   7.7   345   39   20   4.4   2.4   13.5  56.4     1.1      M    M
 15500  -12.8   9.0   340   38   19   4.4   2.4   12.7  54.8     0.3      M    M
 15000  -12.1  10.2   340   37   19   6.3   3.5   11.9  53.4    -0.4    727  3.7
 14500  -10.7  12.7   340   34   18   7.1   3.9   11.2  52.2    -1.2    661  3.4
 14000   -9.6  14.7   340   33   17   7.9   4.3   10.8  51.5    -1.6    614  3.1
 13500   -8.5  16.7   335   32   17   7.9   4.4   10.5  51.0    -2.0    566  2.9
 13000   -7.4  18.7   340   32   16   7.1   3.9   10.2  50.3    -2.4    519  2.6
 12500   -6.4  20.5   340   32   16   7.3   4.0    9.8  49.6    -2.8    474  2.4
 12000   -5.5  22.1   345   31   16   6.5   3.6    9.3  48.7    -3.3    431  2.2
 11750   -4.9  23.2   345   31   16   7.4   4.1    9.1  48.3    -3.6    408  2.1
 11500   -4.4  24.1   345   30   15   7.2   4.0    8.9  48.0    -3.8    385  2.0
 11250   -3.9  25.0   350   29   15   7.1   3.9    8.7  47.6    -4.0    362  1.8
 11000   -3.4  25.9   350   29   15   7.0   3.9    8.5  47.2    -4.2    339  1.7
 10750   -2.9  26.8   350   28   15   7.2   3.9    8.3  46.9    -4.5    317  1.6
 10500   -2.4  27.7   355   28   14   7.2   3.9    8.0  46.5    -4.7    294  1.5
 10250   -1.9  28.6   355   27   14   7.1   3.9    7.9  46.1    -4.9    271  1.4
 10000   -1.3  29.7   360   27   14   7.5   4.1    7.7  45.8    -5.1    248  1.3
  9750   -0.7  30.7   360   27   14   8.5   4.7    7.5  45.5    -5.3    223  1.1
  9500   -0.1  31.8   360   26   14   8.9   4.9    7.5  45.4    -5.4    196  1.0
  9250    0.5  32.9   360   26   13   8.7   4.8    7.4  45.3    -5.5    169  0.9
  9000    1.2  34.2   360   26   13   8.8   4.8    7.3  45.1    -5.6    142  0.7
  8750    1.8  35.2   360   25   13   8.3   4.6    7.2  45.0    -5.7    116  0.6
  8500    2.4  36.3   360   25   13   6.6   3.6    7.1  44.7    -5.8     90  0.5
  8250    2.9  37.2   355   24   12   4.7   2.6    6.7  44.1    -6.1     70  0.4
  8000    3.2  37.8   355   23   12   2.2   1.2    6.3  43.3    -6.6     53  0.3
  7750    3.5  38.3   350   22   12   8.6   4.7    5.8  42.5    -7.0     37  0.2
  7500    4.1  39.4   340   21   11  -0.7  -0.4    5.7  42.3    -7.1     11  0.1
  7250    3.2  37.8   340   18    9 -16.8  -9.2    4.5  40.1    -8.4     31  0.2
  7000    2.3  36.1   335   14    7  -4.8  -2.6    3.2  37.8    -9.6     51  0.3
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           05/03/2016 at 0900 MDT          |       05/03/2016 at 1200 MDT
                                           |
K index... -13.1  LI... +274.7             | K index... -18.9  LI... +274.6
CAPE... +15.8  CIN... -2.6                 | CAPE... +15.8  CIN... -1.2
                                           |
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 -57.9 -72.2  295  32 17   1.7   1.0 | -58.2 -72.8  300  32 16   1.4   0.7
 45000 -55.3 -67.5  300  36 18   0.4   0.2 | -56.3 -69.3  305  33 17  -2.1  -1.1
 40000 -57.7 -71.9  340  29 15  -1.6  -0.9 | -59.0 -74.2  010  26 13  -1.8  -1.0
 38000 -57.2 -71.0  360  30 16   2.7   1.5 | -58.0 -72.4  030  31 16   4.0   2.2
 36000 -55.6 -68.1  025  36 18   2.7   1.5 | -55.6 -68.1  040  39 20   4.0   2.2
 34000 -53.4 -64.1  040  44 23   7.5   4.1 | -52.8 -63.0  045  44 23   7.1   3.9
 32000 -49.0 -56.2  040  50 26   7.3   4.0 | -48.5 -55.3  045  41 21   7.1   3.9
 30000 -44.6 -48.3  040  54 28   7.7   4.2 | -43.7 -46.7  040  39 20   7.3   4.0
 29000 -41.7 -43.1  035  55 28   7.7   4.2 | -41.5 -42.7  040  40 20   7.3   4.0
 28000 -39.4 -38.9  035  55 28   7.7   4.2 | -39.3 -38.7  040  40 20   7.3   4.0
 27000 -37.0 -34.6  035  55 28   8.4   4.6 | -37.0 -34.6  040  40 21   8.8   4.8
 26000 -34.5 -30.1  035  55 28   8.4   4.6 | -34.4 -29.9  040  41 21   8.6   4.7
 25000 -32.0 -25.6  035  55 28   8.4   4.6 | -31.9 -25.4  040  43 22   8.6   4.7
 24000 -29.5 -21.1  035  55 28   8.1   4.4 | -29.3 -20.7  040  44 23   8.5   4.7
 23000 -27.1 -16.8  035  52 27   7.9   4.4 | -26.7 -16.1  040  43 22   8.5   4.7
 22000 -24.8 -12.6  030  50 26   8.0   4.4 | -24.2 -11.6  040  43 22   8.5   4.7
 21000 -22.5  -8.5  030  48 25   5.6   3.1 | -21.8  -7.2  040  41 21   6.5   3.6
 20000 -20.8  -5.4  030  44 23   5.9   3.2 | -19.8  -3.6  040  39 20   6.7   3.7
 19500 -19.9  -3.8  025  43 22   5.8   3.2 | -18.8  -1.8  040  38 20   6.7   3.7
 19000 -19.0  -2.2  025  41 21   5.8   3.2 | -17.8  -0.0  040  37 19   6.8   3.7
 18500 -18.1  -0.6  020  39 20   6.7   3.7 | -16.9   1.6  035  36 19   5.7   3.1
 18000 -17.1   1.2  020  38 20   6.8   3.8 | -16.0   3.2  035  35 18   5.8   3.2
 17500 -16.1   3.0  015  37 19   6.8   3.7 | -15.1   4.8  035  34 17   6.1   3.4
 17000 -15.1   4.8  015  36 19   6.5   3.6 | -14.2   6.4  035  33 17   6.4   3.5
 16500 -14.1   6.6  015  36 18   6.7   3.7 | -13.2   8.2  030  31 16   6.5   3.5
 16000 -13.3   8.1  015  35 18   4.6   2.5 | -12.2  10.0  030  30 16   6.3   3.4
 15500 -12.5   9.5  015  35 18   4.8   2.6 | -11.3  11.7  025  29 15   6.3   3.4
 15000 -11.8  10.8  010  35 18   5.2   2.8 |  -9.8  14.4  025  28 14   6.6   3.6
 14500 -10.6  12.9  005  34 18   5.3   2.9 |  -8.8  16.2  025  27 14   6.6   3.6
 14000  -9.7  14.5  360  34 18   6.5   3.6 |  -7.9  17.8  020  26 13   5.9   3.2
 13500  -8.8  16.2  355  34 17   6.5   3.6 |  -7.1  19.2  015  26 13   6.0   3.3
 13000  -7.9  17.8  355  34 17   7.2   3.9 |  -6.3  20.7  010  26 13   4.6   2.5
 12500  -6.8  19.8  350  34 17   7.1   3.9 |  -5.6  21.9  005  26 14   4.6   2.5
 12000  -5.8  21.6  350  33 17   7.6   4.2 |  -4.8  23.4  360  27 14   6.4   3.5
 11750  -5.3  22.5  355  33 17   7.2   3.9 |  -4.4  24.1  355  27 14   6.5   3.6
 11500  -4.8  23.4  355  33 17   6.9   3.8 |  -3.9  25.0  355  27 14   6.3   3.5
 11250  -4.3  24.3  355  33 17   8.8   4.8 |  -3.5  25.7  350  27 14   8.2   4.5
 11000  -3.6  25.5  355  33 17   8.9   4.9 |  -2.9  26.8  350  26 13   8.8   4.9
 10750  -3.1  26.4  355  33 17   7.1   3.9 |  -2.4  27.7  350  25 13   7.7   4.2
 10500  -2.5  27.5  355  33 17   7.5   4.1 |  -1.9  28.6  350  24 13   8.3   4.6
 10250  -2.0  28.4  355  32 17   8.1   4.5 |  -1.3  29.7  350  24 12   9.7   5.3
 10000  -1.4  29.5  355  32 16   8.4   4.6 |  -0.5  31.1  350  23 12  10.4   5.7
  9750  -0.9  30.4  355  32 16   7.2   4.0 |   0.2  32.4  350  23 12   9.3   5.1
  9500  -0.4  31.3  355  31 16   7.0   3.8 |   0.8  33.4  350  22 11   9.3   5.1
  9250   0.1  32.2  355  30 16   7.5   4.1 |   1.5  34.7  350  22 11   9.8   5.4
  9000   0.7  33.3  355  29 15   7.5   4.1 |   2.3  36.1  350  21 11  10.0   5.5
  8750   1.2  34.2  355  28 15   8.7   4.8 |   3.0  37.4  350  21 11  10.0   5.5
  8500   1.9  35.4  355  27 14   9.5   5.2 |   3.7  38.7  350  21 11  10.4   5.7
  8250   2.6  36.7  355  25 13   8.8   4.9 |   4.5  40.1  350  21 11  10.9   6.0
  8000   3.3  37.9  350  22 11   8.5   4.7 |   5.3  41.5  350  20 10  10.2   5.6
  7750   3.9  39.0  345  20 10   9.8   5.4 |   6.1  43.0  350  20 10  12.9   7.1
  7500   4.6  40.3  345  19 10   8.9   4.9 |   7.1  44.8  350  19 10  12.8   7.0
  7250   5.2  41.4  345  17  9   6.6   3.6 |   7.9  46.2  350  18  9   9.4   5.1
  7000   5.7  42.3  340  15  8   8.5   4.6 |   8.6  47.5  350  17  9  12.2   6.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           05/03/2016 at 1500 MDT          |       05/03/2016 at 1800 MDT
                                           |
K index... -23.4  LI... +275.9             | K index... -12.8  LI... +275.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -58.7 -73.7  300  29 15   1.2   0.7 | -59.7 -75.5  300  29 15   0.8   0.5
 45000 -57.1 -70.8  315  29 15  -2.6  -1.4 | -58.5 -73.3  315  24 13  -1.5  -0.8
 40000 -60.3 -76.5  010  27 14  -2.2  -1.2 | -60.4 -76.7  010  27 14  -1.2  -0.6
 38000 -58.8 -73.8  025  31 16   5.4   3.0 | -58.3 -72.9  020  30 16   5.7   3.1
 36000 -55.5 -67.9  035  36 18   5.4   3.0 | -54.9 -66.8  030  33 17   5.7   3.1
 34000 -52.0 -61.6  040  38 20   7.2   3.9 | -51.2 -60.2  030  34 17   7.4   4.1
 32000 -47.1 -52.8  040  35 18   7.2   4.0 | -46.2 -51.2  030  30 16   7.4   4.1
 30000 -42.9 -45.2  040  32 16   6.8   3.7 | -41.8 -43.2  025  28 14   6.9   3.8
 29000 -40.8 -41.4  040  31 16   6.8   3.7 | -39.8 -39.6  025  26 14   6.9   3.8
 28000 -38.8 -37.8  040  30 16   6.8   3.7 | -37.7 -35.9  025  25 13   7.0   3.8
 27000 -36.6 -33.9  040  30 16   8.4   4.6 | -35.5 -31.9  020  25 13   7.9   4.3
 26000 -34.1 -29.4  040  31 16   8.3   4.6 | -33.1 -27.6  025  25 13   7.9   4.3
 25000 -31.6 -24.9  040  32 17   8.3   4.6 | -30.8 -23.4  025  25 13   7.9   4.3
 24000 -29.1 -20.4  040  33 17   8.6   4.7 | -28.4 -19.1  025  25 13   8.0   4.4
 23000 -26.5 -15.7  040  33 17   8.6   4.7 | -26.0 -14.8  030  25 13   8.0   4.4
 22000 -24.0 -11.2  040  32 17   8.6   4.7 | -23.6 -10.5  030  25 13   8.0   4.4
 21000 -21.5  -6.7  040  32 16   7.3   4.0 | -21.3  -6.3  035  24 12   7.5   4.1
 20000 -19.3  -2.7  040  31 16   7.4   4.0 | -19.1  -2.4  035  23 12   7.6   4.2
 19500 -18.2  -0.8  040  31 16   7.4   4.0 | -17.9  -0.2  035  23 12   7.6   4.2
 19000 -17.1   1.2  040  31 16   7.4   4.0 | -16.8   1.8  035  22 11   7.6   4.2
 18500 -16.0   3.2  040  30 15   7.5   4.1 | -15.6   3.9  030  22 11   8.2   4.5
 18000 -14.8   5.4  040  29 15   7.5   4.1 | -14.4   6.1  030  21 11   8.1   4.5
 17500 -13.7   7.3  040  28 14   7.1   3.9 | -13.2   8.2  030  21 11   8.1   4.4
 17000 -12.7   9.1  040  27 14   6.9   3.8 | -12.0  10.4  030  20 10   8.1   4.4
 16500 -11.6  11.1  035  26 13   6.7   3.7 | -10.8  12.6  025  20 10   8.0   4.4
 16000 -10.7  12.7  035  24 12   6.1   3.4 |  -9.6  14.7  025  19 10   8.0   4.4
 15500  -9.3  15.3  030  22 12   6.3   3.5 |  -7.7  18.1  020  18  9   7.3   4.0
 15000  -8.3  17.1  025  21 11   6.4   3.5 |  -6.7  19.9  015  19 10   6.9   3.8
 14500  -7.3  18.9  020  20 10   6.4   3.5 |  -5.6  21.9  010  19 10   6.7   3.7
 14000  -6.4  20.5  015  20 10   6.2   3.4 |  -4.7  23.5  005  19 10   6.0   3.3
 13500  -5.5  22.1  010  20 10   6.3   3.4 |  -3.7  25.3  005  20 10   6.0   3.3
 13000  -4.5  23.9  005  20 10   6.6   3.6 |  -2.8  27.0  360  20 11   6.1   3.3
 12500  -3.5  25.7  360  20 10   6.5   3.6 |  -1.9  28.6  355  21 11   6.8   3.7
 12000  -2.6  27.3  355  20 11   6.6   3.6 |  -0.9  30.4  355  21 11   6.6   3.6
 11750  -2.1  28.2  355  20 11   6.7   3.7 |  -0.4  31.3  355  21 11   6.8   3.7
 11500  -1.6  29.1  350  20 11   6.6   3.6 |   0.1  32.2  355  21 11   6.7   3.7
 11250  -1.1  30.0  350  20 10   8.3   4.5 |   0.6  33.1  355  21 11   7.0   3.9
 11000  -0.5  31.1  350  20 10   7.4   4.1 |   1.1  34.0  355  20 10   6.7   3.7
 10750  -0.1  31.8  350  19 10   5.7   3.1 |   1.6  34.9  355  20 10   6.2   3.4
 10500   0.3  32.5  345  18  9   6.9   3.8 |   2.1  35.8  355  19 10   6.3   3.5
 10250   0.7  33.3  345  18  9   9.3   5.1 |   2.5  36.5  355  18 10   6.8   3.7
 10000   1.5  34.7  345  18  9  10.3   5.7 |   2.9  37.2  355  18  9   7.4   4.0
  9750   2.2  36.0  345  18  9   9.3   5.1 |   3.4  38.1  355  17  9   7.1   3.9
  9500   2.8  37.0  350  18  9   9.4   5.2 |   3.8  38.8  350  15  8   7.8   4.3
  9250   3.5  38.3  350  17  9   9.7   5.3 |   4.4  39.9  350  14  7   9.3   5.1
  9000   4.3  39.7  345  17  9   9.6   5.3 |   5.1  41.2  350  14  7   9.6   5.3
  8750   5.0  41.0  345  17  9  10.8   5.9 |   5.8  42.4  350  14  7   9.9   5.4
  8500   5.8  42.4  345  17  9  11.2   6.2 |   6.6  43.9  350  14  7  10.2   5.6
  8250   6.6  43.9  345  17  9  10.5   5.8 |   7.3  45.1  350  14  7  10.2   5.6
  8000   7.4  45.3  345  16  8  10.2   5.6 |   8.1  46.6  350  14  7   9.9   5.5
  7750   8.2  46.8  345  16  8  11.7   6.4 |   8.8  47.8  350  14  7  11.1   6.1
  7500   9.1  48.4  345  16  8  11.9   6.5 |   9.6  49.3  350  13  7   8.7   4.8
  7250   9.9  49.8  345  15  8  10.1   5.5 |  10.0  50.0  350  13  6   5.2   2.8
  7000  10.6  51.1  345  15  8  11.6   6.4 |  10.5  50.9  350  12  6   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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