Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 271105
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0505 MDT Saturday, June 27, 2015

This forecast is for Saturday, June 27, 2015:

If the trigger temperature of 71.6 F/22.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 685 ft/min (3.5 m/s)
   Maximum height of thermals.................. 15077 ft MSL (7909 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1000 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................. 11816 ft MSL (4647 ft AGL)
Thermal soaring outlook for Sunday 06/28....... Good

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

Remarks...

Sunrise/Sunset.................... 05:35:37 / 20:28:26 MDT
Total possible sunshine........... 14 hr 52 min 50 sec (892 min 50 sec)
Altitude of sun at 13:02:05 MDT... 74.33 degrees

Upper air data from numerical model forecast valid on 06/27/2015 at 0600 MDT

Freezing level.................. 16173 ft MSL (9005 ft AGL)
Convective condensation level... 13462 ft MSL (6294 ft AGL)
Lifted condensation level....... 14088 ft MSL (6920 ft AGL)
Lifted index.................... -5.7
K index......................... +5.1

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  -64.4 -83.9   315   23   12   0.7   0.4      M     M       M      M    M
 45000  -61.8 -79.2   305   34   18   4.1   2.2      M     M       M      M    M
 40000  -54.5 -66.1   285   35   18   8.0   4.4      M     M       M      M    M
 38000  -49.7 -57.5   290   33   17   8.0   4.4      M     M       M      M    M
 36000  -44.9 -48.8   300   31   16   8.3   4.5      M     M       M      M    M
 34000  -39.7 -39.5   310   29   15   8.7   4.8      M     M       M      M    M
 32000  -34.5 -30.1   325   28   15   8.8   4.8      M     M       M      M    M
 30000  -30.0 -22.0   335   27   14   7.3   4.0   40.2 104.4    11.0      M    M
 29000  -27.8 -18.0   340   26   14   7.4   4.0   39.4 102.9    10.4      M    M
 28000  -25.6 -14.1   340   26   13   7.4   4.0   38.6 101.5     9.9      M    M
 27000  -23.4 -10.1   340   26   13   7.4   4.0   37.6  99.6     9.2      M    M
 26000  -21.2  -6.2   340   26   13   7.4   4.0   36.7  98.1     8.6      M    M
 25000  -18.5  -1.3   340   26   13   7.1   3.9   35.7  96.3     7.9      M    M
 24000  -16.4   2.5   335   26   13   7.0   3.8   34.6  94.3     7.1      M    M
 23000  -14.3   6.3   335   25   13   7.0   3.8   33.7  92.6     6.3      M    M
 22000  -12.2  10.0   335   25   13   6.9   3.8   32.8  91.0     5.6      M    M
 21000  -10.1  13.8   335   24   12   6.9   3.8   31.7  89.0     4.7      M    M
 20000   -8.1  17.4   335   23   12   6.9   3.8   30.7  87.3     4.0      M    M
 19500   -7.1  19.2   335   23   12   7.1   3.9   30.3  86.6     3.6      M    M
 19000   -6.0  21.2   340   22   12   7.4   4.0   29.9  85.8     3.2      M    M
 18500   -4.9  23.2   340   22   11   7.4   4.1   29.5  85.1     2.9      M    M
 18000   -3.8  25.2   345   22   11   6.9   3.8   29.1  84.3     2.5      M    M
 17500   -2.8  27.0   350   22   11   6.9   3.8   28.6  83.4     2.0      M    M
 17000   -1.8  28.8   350   23   12   7.1   3.9   28.1  82.6     1.6      M    M
 16500   -0.7  30.7   350   22   11   7.3   4.0   27.7  81.8     1.2      M    M
 16000    0.3  32.5   355   21   11   7.4   4.0   27.3  81.1     0.8      M    M
 15500    1.4  34.5   355   20   10   6.5   3.6   26.8  80.3     0.4      M    M
 15000    2.4  36.3   355   18    9   6.6   3.6   26.3  79.4    -0.0    681  3.5
 14500    3.4  38.1   355   17    9   7.4   4.0   25.9  78.5    -0.4    635  3.2
 14000    4.5  40.1   350   17    9   7.5   4.1   25.5  77.9    -0.8    588  3.0
 13500    5.6  42.1   345   17    9   7.4   4.1   25.2  77.3    -1.2    540  2.7
 13000    6.7  44.1   345   18    9   7.2   4.0   24.7  76.5    -1.6    493  2.5
 12500    7.8  46.0   350   18    9   6.3   3.5   24.4  75.8    -1.9    445  2.3
 12000    8.6  47.5   350   16    8   7.4   4.1   23.8  74.9    -2.7    407  2.1
 11750    9.0  48.2   345   15    8   7.6   4.1   23.6  74.5    -3.0    387  2.0
 11500    9.4  48.9   345   14    7   7.5   4.1   23.5  74.3    -3.3    366  1.9
 11250    9.8  49.6   345   13    7   6.5   3.6   23.3  73.9    -3.6    348  1.8
 11000   10.2  50.4   340   11    6   8.2   4.5   23.0  73.5    -4.1    330  1.7
 10750   10.8  51.4   335   10    5  10.0   5.5   23.0  73.4    -4.2    305  1.5
 10500   11.4  52.5   325    9    5   9.2   5.0   23.0  73.4    -4.3    280  1.4
 10250   11.9  53.4   315    8    4   8.3   4.5   22.9  73.3    -4.5    256  1.3
 10000   12.4  54.3   305    8    4   7.8   4.3   22.8  73.0    -4.8    234  1.2
  9750   13.3  55.9   280    9    5   5.2   2.8   22.3  72.2    -5.4    193  1.0
  9500   13.5  56.3   270    9    5   4.1   2.2   21.9  71.5    -5.9    177  0.9
  9250   13.8  56.8   265   10    5   3.0   1.7   21.5  70.6    -6.4    163  0.8
  9000   14.0  57.2   260   10    5   5.7   3.1   21.0  69.8    -6.9    149  0.8
  8750   14.4  57.9   255   11    6   3.6   2.0   20.7  69.3    -7.2    129  0.7
  8500   14.4  57.9   250   11    5  -1.8  -1.0   20.0  68.0    -8.0    123  0.6
  8250   14.2  57.6   240   10    5  -2.1  -1.1   19.1  66.4    -9.0    121  0.6
  8000   14.0  57.2   230   10    5  -1.0  -0.6   18.2  64.8    -9.9    119  0.6
  7750   14.0  57.2   220   11    6   0.3   0.1   17.5  63.5   -10.7    113  0.6
  7500   13.9  57.0   210    9    5  -0.8  -0.4   16.7  62.1   -11.4    107  0.5
  7250   13.9  57.0   195    7    3   2.0   1.1   16.0  60.8   -12.2    100  0.5
  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 * * * * * *

           06/27/2015 at 0900 MDT          |       06/27/2015 at 1200 MDT
                                           |
K index... +2.5  LI... +269.1              | K index... +6.5  LI... +272.1
CAPE... +1485.2  CIN... -44.8              | CAPE... +499.0  CIN... -18.3
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.9 -83.0  325  23 12   0.7   0.4 | -63.8 -82.8  330  20 10   1.2   0.7
 45000 -61.6 -78.9  320  33 17   3.3   1.8 | -61.1 -78.0  330  28 14   3.1   1.7
 40000 -55.4 -67.7  305  29 15   8.1   4.4 | -55.2 -67.4  320  21 11   7.6   4.2
 38000 -50.5 -58.9  300  28 15   8.0   4.4 | -50.7 -59.3  320  21 11   7.5   4.1
 36000 -45.7 -50.3  300  28 14   8.3   4.6 | -46.2 -51.2  320  21 11   8.1   4.4
 34000 -40.5 -40.9  315  24 13   8.8   4.8 | -40.8 -41.4  325  19 10   9.0   4.9
 32000 -35.2 -31.4  330  22 11   9.0   4.9 | -35.4 -31.7  330  17  9   9.2   5.0
 30000 -30.5 -22.9  340  22 11   7.8   4.3 | -30.4 -22.7  340  16  8   8.1   4.5
 29000 -28.1 -18.6  340  22 11   7.8   4.3 | -28.0 -18.4  340  16  8   8.1   4.5
 28000 -25.8 -14.4  345  22 12   7.3   4.0 | -25.6 -14.1  345  16  8   7.6   4.2
 27000 -23.6 -10.5  345  23 12   7.2   4.0 | -23.3  -9.9  345  17  9   7.6   4.2
 26000 -21.5  -6.7  345  24 12   7.3   4.0 | -20.5  -4.9  345  19 10   7.6   4.2
 25000 -18.8  -1.8  345  25 13   7.2   4.0 | -18.2  -0.8  350  20 10   7.5   4.1
 24000 -16.6   2.1  340  25 13   7.2   4.0 | -15.9   3.4  350  21 11   7.5   4.1
 23000 -14.4   6.1  340  26 13   7.2   4.0 | -13.7   7.3  350  22 11   7.5   4.1
 22000 -12.3   9.9  340  26 13   6.9   3.8 | -11.5  11.3  350  23 12   6.7   3.7
 21000 -10.2  13.6  340  25 13   6.9   3.8 |  -9.5  14.9  350  23 12   6.7   3.7
 20000  -8.2  17.2  345  24 12   6.9   3.8 |  -7.5  18.5  350  23 12   6.7   3.7
 19500  -7.1  19.2  345  23 12   6.8   3.7 |  -6.5  20.3  350  23 12   6.4   3.5
 19000  -6.2  20.8  345  24 12   6.5   3.6 |  -5.6  21.9  350  24 12   6.0   3.3
 18500  -5.2  22.6  350  24 12   6.5   3.6 |  -4.7  23.5  350  24 12   6.0   3.3
 18000  -4.2  24.4  355  24 13   6.8   3.7 |  -3.8  25.2  350  25 13   6.3   3.4
 17500  -3.2  26.2  355  25 13   6.8   3.7 |  -2.9  26.8  355  26 14   6.3   3.4
 17000  -2.2  28.0  355  25 13   7.0   3.9 |  -2.0  28.4  355  28 14   6.5   3.6
 16500  -1.2  29.8  355  25 13   7.4   4.0 |  -1.0  30.2  355  29 15   6.8   3.7
 16000  -0.1  31.8  360  25 13   7.4   4.1 |  -0.0  32.0  355  31 16   6.8   3.7
 15500   1.0  33.8  360  23 12   7.9   4.3 |   1.1  34.0  360  31 16   8.0   4.4
 15000   2.1  35.8  360  22 11   8.0   4.4 |   2.2  36.0  360  31 16   8.1   4.4
 14500   3.2  37.8  360  20 10   7.5   4.1 |   3.3  37.9  360  30 15   7.9   4.4
 14000   4.4  39.9  360  18  9   7.5   4.1 |   4.4  39.9  360  27 14   8.0   4.4
 13500   5.5  41.9  360  16  8   7.7   4.2 |   5.5  41.9  360  24 12   7.7   4.2
 13000   6.7  44.1  360  15  7   7.7   4.2 |   6.6  43.9  360  21 11   7.4   4.0
 12500   7.9  46.2  360  13  7   6.9   3.8 |   7.8  46.0  360  17  9   6.5   3.5
 12000   9.0  48.2  360  13  6   9.0   4.9 |   8.8  47.8  355  15  8   8.9   4.9
 11750   9.7  49.5  360  12  6   8.8   4.8 |   9.3  48.7  355  13  7   8.5   4.7
 11500  10.3  50.5  360  12  6   8.1   4.5 |   9.9  49.8  355  12  6   8.9   4.9
 11250  10.8  51.4  360  12  6   6.9   3.8 |  10.5  50.9  355  11  6   9.0   4.9
 11000  11.3  52.3  360  12  6   7.2   4.0 |  11.1  52.0  355  10  5   9.5   5.2
 10750  11.8  53.2  360  12  6   7.4   4.1 |  11.8  53.2  355  10  5   9.7   5.3
 10500  12.3  54.1  360  12  6   7.8   4.3 |  12.5  54.5  355  10  5   9.9   5.4
 10250  12.8  55.0  355  11  6   8.6   4.7 |  13.3  55.9  360   9  5  10.5   5.8
 10000  13.4  56.1  350  10  5   8.8   4.8 |  14.7  58.5  360   9  4   9.2   5.0
  9750  14.5  58.1  340   9  5   8.3   4.6 |  15.4  59.7  360   8  4   9.2   5.0
  9500  15.1  59.2  335   8  4   8.2   4.5 |  16.1  61.0  360   8  4  10.1   5.5
  9250  15.6  60.1  330   8  4   7.8   4.3 |  16.8  62.2  005   8  4  10.3   5.7
  9000  16.2  61.2  325   8  4   9.3   5.1 |  17.5  63.5  005   7  4   9.4   5.1
  8750  16.7  62.1  325   8  4   6.8   3.7 |  18.2  64.8  005   7  4   9.5   5.2
  8500  16.9  62.4  315   6  3   3.0   1.6 |  18.9  66.0  010   7  3  10.7   5.9
  8250  17.0  62.6  300   5  3   5.1   2.8 |  19.7  67.5  010   6  3  10.5   5.7
  8000  17.1  62.8  275   5  2   0.4   0.2 |  20.5  68.9  010   6  3  10.8   5.9
  7750  16.9  62.4  260   4  2   5.0   2.8 |  21.4  70.5  010   6  3  16.6   9.1
  7500  18.0  64.4  240   4  2  26.1  14.3 |  22.9  73.2  015   6  3  25.3  13.9
  7250  19.1  66.4  225   4  2 -15.3  -8.4 |  24.5  76.1  020   5  3  10.4   5.7
  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

           06/27/2015 at 1500 MDT          |       06/27/2015 at 1800 MDT
                                           |
K index... +10.3  LI... +272.7             | K index... +19.8  LI... +271.6
CAPE... +157.4  CIN... -18.8               | CAPE... +264.2  CIN... -25.8
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -63.9 -83.0  325  20 10   0.8   0.5 | -63.9 -83.0  330  21 11   0.4   0.2
 45000 -61.4 -78.5  325  25 13   3.6   2.0 | -61.7 -79.1  320  28 14   4.0   2.2
 40000 -54.9 -66.8  325  19 10   7.3   4.0 | -54.5 -66.1  310  26 13   7.6   4.2
 38000 -50.5 -58.9  325  18  9   7.3   4.0 | -50.0 -58.0  315  24 12   7.6   4.1
 36000 -46.1 -51.0  330  17  9   7.9   4.3 | -45.5 -49.9  315  23 12   8.0   4.4
 34000 -40.8 -41.4  330  16  8   8.9   4.9 | -40.3 -40.5  320  20 11   8.7   4.8
 32000 -35.5 -31.9  325  15  8   9.0   5.0 | -35.1 -31.2  325  18  9   9.0   4.9
 30000 -30.5 -22.9  330  14  7   8.2   4.5 | -30.2 -22.4  335  17  9   8.0   4.4
 29000 -28.1 -18.6  335  14  7   8.2   4.5 | -27.8 -18.0  335  16  8   8.0   4.4
 28000 -25.6 -14.1  335  14  7   7.9   4.3 | -25.4 -13.7  340  15  8   7.7   4.2
 27000 -23.3  -9.9  340  15  8   7.9   4.3 | -22.5  -8.5  345  16  8   7.6   4.2
 26000 -20.3  -4.5  345  16  8   7.9   4.3 | -20.2  -4.4  350  17  9   7.7   4.2
 25000 -18.0  -0.4  345  18  9   7.3   4.0 | -18.0  -0.4  350  18  9   7.0   3.8
 24000 -15.8   3.6  345  19 10   7.2   4.0 | -15.9   3.4  355  19 10   6.9   3.8
 23000 -13.6   7.5  345  20 11   7.3   4.0 | -13.9   7.0  355  21 11   6.9   3.8
 22000 -11.5  11.3  345  22 11   6.4   3.5 | -11.8  10.8  355  23 12   6.1   3.3
 21000  -9.6  14.7  345  24 12   6.4   3.5 | -10.1  13.8  355  25 13   6.1   3.4
 20000  -7.7  18.1  345  25 13   6.4   3.5 |  -8.3  17.1  350  27 14   6.3   3.4
 19500  -6.7  19.9  345  26 13   6.4   3.5 |  -7.4  18.7  350  28 14   6.7   3.7
 19000  -5.8  21.6  345  27 14   6.2   3.4 |  -6.4  20.5  350  28 14   7.3   4.0
 18500  -4.9  23.2  345  27 14   6.2   3.4 |  -5.3  22.5  350  28 15   7.3   4.0
 18000  -3.9  25.0  350  28 15   7.0   3.8 |  -4.3  24.3  350  28 15   7.6   4.1
 17500  -2.9  26.8  350  29 15   7.0   3.8 |  -3.1  26.4  350  28 15   7.6   4.2
 17000  -1.9  28.6  350  30 15   7.3   4.0 |  -2.0  28.4  355  28 15   8.0   4.4
 16500  -0.8  30.6  355  30 16   7.7   4.2 |  -0.8  30.6  355  28 14   8.5   4.7
 16000   0.4  32.7  355  31 16   7.7   4.2 |   0.5  32.9  355  27 14   8.5   4.7
 15500   1.6  34.9  355  31 16   8.6   4.7 |   1.8  35.2  355  26 13   8.7   4.8
 15000   2.8  37.0  360  30 15   8.6   4.7 |   3.0  37.4  360  25 13   8.7   4.8
 14500   4.0  39.2  360  29 15   8.4   4.6 |   4.3  39.7  360  23 12   8.3   4.6
 14000   5.2  41.4  005  27 14   8.5   4.7 |   5.5  41.9  005  21 11   8.3   4.6
 13500   6.4  43.5  005  24 13   8.0   4.4 |   6.7  44.1  005  19 10   7.6   4.2
 13000   7.4  45.3  010  20 10   7.8   4.3 |   7.7  45.9  010  15  8   7.4   4.1
 12500   8.5  47.3  010  16  8   8.4   4.6 |   8.6  47.5  015  11  6   8.2   4.5
 12000   9.8  49.6  015  14  7   9.3   5.1 |   9.9  49.8  025   9  5   9.3   5.1
 11750  10.4  50.7  015  12  6   9.3   5.1 |  10.6  51.1  030   9  4   9.2   5.1
 11500  11.0  51.8  020  11  6   9.8   5.3 |  11.2  52.2  035   8  4   9.8   5.4
 11250  11.8  53.2  020  11  5  10.4   5.7 |  12.0  53.6  035   8  4  10.6   5.8
 11000  12.6  54.7  020  11  5  10.0   5.5 |  12.7  54.9  035   8  4   9.9   5.4
 10750  13.3  55.9  025  11  5   9.6   5.3 |  13.4  56.1  040   8  4   9.3   5.1
 10500  14.0  57.2  025  11  5   9.9   5.4 |  14.1  57.4  040   8  4   9.8   5.4
 10250  14.7  58.5  025  10  5  10.3   5.7 |  15.7  60.3  040   8  4  10.3   5.6
 10000  16.2  61.2  025  10  5   9.4   5.1 |  16.4  61.5  040   8  4   9.1   5.0
  9750  16.9  62.4  025  10  5   9.7   5.3 |  17.1  62.8  040   8  4   9.2   5.0
  9500  17.7  63.9  025  10  5  10.5   5.7 |  17.8  64.0  040   8  4  10.0   5.5
  9250  18.5  65.3  025  10  5  10.8   5.9 |  18.5  65.3  040   8  4  10.3   5.6
  9000  19.2  66.6  025  10  5   9.7   5.3 |  19.3  66.7  040   8  4   9.6   5.3
  8750  19.9  67.8  025  10  5   9.6   5.3 |  20.0  68.0  040   8  4   9.6   5.3
  8500  20.7  69.3  025  10  5  10.7   5.9 |  20.7  69.3  040   8  4  10.3   5.7
  8250  21.5  70.7  025  10  5  10.9   6.0 |  21.5  70.7  045   8  4  10.5   5.8
  8000  22.3  72.1  025  10  5   9.8   5.4 |  22.3  72.1  045   8  4   9.8   5.4
  7750  23.1  73.6  025  10  5  15.2   8.3 |  23.0  73.4  045   8  4  11.8   6.5
  7500  24.6  76.3  030   9  5  26.9  14.8 |  24.0  75.2  045   8  4  17.2   9.4
  7250  26.2  79.2  030   9  5   5.3   2.9 |  25.1  77.2  045   7  4   7.2   3.9
  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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