Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 260016
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1816 MDT Sunday, June 25, 2017

This forecast is for Monday, June 26, 2017:

If the trigger temperature of 75.4 F/24.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 995 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16560 ft MSL (11253 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1045 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................. 11813 ft MSL (6506 ft AGL)
Thermal soaring outlook for Tuesday 06/27...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 32071 ft MSL (26764 ft AGL)
Wave soaring outlook for Tuesday 06/27......... Poor

Remarks...

Sunrise/Sunset.................... 05:33:19 / 20:31:30 MDT
Total possible sunshine........... 14 hr 58 min 11 sec (898 min 11 sec)
Altitude of sun at 13:02:29 MDT... 73.53 degrees

Upper air data from numerical model forecast valid on 06/26/2017 at 0600 MDT

Freezing level.................. 14422 ft MSL (9115 ft AGL)
Convective condensation level... 12293 ft MSL (6986 ft AGL)
Lifted condensation level....... 13578 ft MSL (8271 ft AGL)
Lifted index.................... -6.9
K index......................... +18.5

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  -62.8 -81.0   315   39   20   1.2   0.7      M     M       M      M    M
 45000  -60.0 -76.0   305   42   22   3.8   2.1      M     M       M      M    M
 40000  -53.8 -64.8   295   30   16   6.1   3.3      M     M       M      M    M
 38000  -50.2 -58.4   300   30   15   6.0   3.3      M     M       M      M    M
 36000  -46.6 -51.9   300   30   15   6.0   3.3      M     M       M      M    M
 34000  -42.4 -44.3   305   32   16   7.4   4.0      M     M       M      M    M
 32000  -38.0 -36.4   310   34   17   7.3   4.0      M     M       M      M    M
 30000  -33.9 -29.0   315   34   18   6.6   3.6   42.3 108.1     9.8      M    M
 29000  -31.5 -24.7   315   34   18   6.6   3.6   40.8 105.4     8.7      M    M
 28000  -29.5 -21.1   320   34   18   7.2   3.9   39.7 103.5     8.0      M    M
 27000  -27.3 -17.1   320   34   18   7.5   4.1   38.7 101.7     7.3      M    M
 26000  -25.1 -13.2   325   34   18   7.5   4.1   37.9 100.2     6.7      M    M
 25000  -22.8  -9.0   325   34   18   7.5   4.1   37.1  98.8     6.2      M    M
 24000  -20.5  -4.9   325   33   17   7.9   4.3   36.3  97.4     5.6      M    M
 23000  -18.1  -0.6   325   33   17   7.9   4.3   35.6  96.2     5.1      M    M
 22000  -15.8   3.6   325   32   16   7.9   4.3   35.1  95.1     4.7      M    M
 21000  -13.4   7.9   325   30   16   7.9   4.3   34.3  93.8     4.1      M    M
 20000  -11.1  12.0   325   29   15   7.9   4.3   33.7  92.6     3.6      M    M
 19500   -9.9  14.2   330   28   14   8.1   4.4   33.4  92.1     3.3      M    M
 19000   -8.8  16.2   330   27   14   6.1   3.3   33.0  91.3     3.0      M    M
 18500   -7.9  17.8   330   26   14   6.2   3.4   32.4  90.2     2.4      M    M
 18000   -7.0  19.4   330   26   13   6.2   3.4   31.8  89.2     1.9      M    M
 17500   -6.2  20.8   330   24   12   6.0   3.3   31.1  88.0     1.3      M    M
 17000   -5.3  22.5   330   22   11   6.1   3.3   30.5  86.9     0.7      M    M
 16500   -4.5  23.9   325   21   11   5.6   3.1   29.8  85.7     0.1      M    M
 16000   -3.7  25.3   325   19   10   5.7   3.1   29.1  84.4    -0.6    959  4.9
 15500   -2.8  27.0   325   18    9   7.2   3.9   28.5  83.4    -1.2    919  4.7
 15000   -1.2  29.8   330   16    8   7.7   4.2   28.0  82.5    -1.7    846  4.3
 14500    0.1  32.2   330   14    7   9.3   5.1   27.8  82.1    -2.0    795  4.0
 14000    1.5  34.7   335   13    7   9.4   5.1   27.7  81.9    -2.0    738  3.7
 13500    2.9  37.2   335   11    6   8.2   4.5   27.6  81.7    -2.1    682  3.5
 13000    4.0  39.2   340   10    5   7.9   4.3   27.3  81.2    -2.5    633  3.2
 12500    5.1  41.2   340    9    5   8.3   4.6   27.0  80.6    -2.8    584  3.0
 12000    6.4  43.5   350    8    4   8.6   4.7   26.8  80.3    -3.0    530  2.7
 11500    7.7  45.9   360    7    4   8.2   4.5   26.7  80.0    -3.1    477  2.4
 11000    8.9  48.0   355    5    2   7.7   4.2   26.4  79.5    -3.5    428  2.2
 10500   10.0  50.0   340    3    1   4.2   2.3   26.1  78.9    -3.9    380  1.9
 10250   10.1  50.2   335    2    1   4.0   2.2   25.5  77.8    -4.5    369  1.9
 10000   10.6  51.1   325    2    1  10.1   5.5   25.3  77.6    -4.7    346  1.8
  9750   11.3  52.3   315    3    1  10.6   5.8   25.4  77.7    -4.8    320  1.6
  9500   11.9  53.4   300    3    1   8.1   4.4   25.4  77.7    -4.9    293  1.5
  9250   12.3  54.1   290    3    2   5.3   2.9   25.1  77.2    -5.2    273  1.4
  9000   12.8  55.0   275    4    2   9.2   5.0   24.9  76.8    -5.5    253  1.3
  8750   13.5  56.3   265    5    3  11.3   6.2   25.0  76.9    -5.5    223  1.1
  8500   14.1  57.4   255    7    4   6.9   3.8   24.9  76.9    -5.7    198  1.0
  8250   14.4  57.9   250    8    4   5.0   2.7   24.6  76.2    -6.1    181  0.9
  8000   14.7  58.5   245    9    5   4.8   2.7   24.2  75.6    -6.6    165  0.8
  7750   14.9  58.8   245   10    5   3.6   2.0   23.8  74.8    -7.1    151  0.8
  7500   15.1  59.2   245   10    5   4.0   2.2   23.3  74.0    -7.6    138  0.7
  7250   15.3  59.5   240    9    5   4.2   2.3   22.9  73.2    -8.1    123  0.6
  7000   15.6  60.1   240    9    5   4.5   2.5   22.5  72.5    -8.6    109  0.6
  6750   15.8  60.4   240    8    4   3.1   1.7   22.1  71.7    -9.1     94  0.5
  6500   15.9  60.6   230    8    4   1.2   0.7   21.5  70.6    -9.8     84  0.4
  6250   16.0  60.8   220    7    4   2.8   1.5   20.9  69.6   -10.5     73  0.4
  6000   16.1  61.0   215    7    3  -1.6  -0.9   20.3  68.5   -11.1     63  0.3
  5750   15.7  60.3   205    5    2  -7.4  -4.0   19.1  66.5   -12.3     69  0.3
  5500   15.2  59.4   200    2    1  -4.4  -2.4   17.9  64.3   -13.5     76  0.4

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

           06/26/2017 at 0900 MDT          |       06/26/2017 at 1200 MDT
                                           |
K index... +14.1  LI... -3.2               | K index... +7.7  LI... -4.5
CAPE... +881.6  CIN... -109.7              | CAPE... +1528.3  CIN... -10.6
                                           |
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 -62.5 -80.5  325  36 19   1.8   1.0 | -62.6 -80.7  325  36 19   2.2   1.2
 45000 -59.3 -74.7  315  43 22   3.3   1.8 | -58.9 -74.0  320  43 22   3.3   1.8
 40000 -53.8 -64.8  310  35 18   5.9   3.2 | -53.5 -64.3  310  42 22   5.1   2.8
 38000 -50.4 -58.7  310  34 17   5.7   3.2 | -50.5 -58.9  310  39 20   5.0   2.8
 36000 -47.0 -52.6  310  32 16   5.8   3.2 | -47.5 -53.5  310  37 19   5.0   2.8
 34000 -42.8 -45.0  315  33 17   7.2   4.0 | -43.6 -46.5  315  34 18   7.0   3.8
 32000 -38.5 -37.3  320  35 18   7.2   4.0 | -39.4 -38.9  325  33 17   7.0   3.8
 30000 -33.9 -29.0  330  34 18   6.7   3.7 | -34.4 -29.9  335  31 16   7.5   4.1
 29000 -31.9 -25.4  330  34 17   6.7   3.7 | -32.2 -26.0  340  30 15   7.5   4.1
 28000 -29.9 -21.8  335  33 17   7.3   4.0 | -30.0 -22.0  340  29 15   7.9   4.3
 27000 -27.6 -17.7  335  33 17   7.7   4.2 | -27.5 -17.5  340  28 14   8.1   4.5
 26000 -25.3 -13.5  330  33 17   7.7   4.2 | -25.1 -13.2  340  27 14   8.1   4.5
 25000 -23.0  -9.4  330  34 17   7.7   4.2 | -22.7  -8.9  335  27 14   8.2   4.5
 24000 -20.6  -5.1  330  33 17   8.0   4.4 | -20.2  -4.4  335  26 14   8.4   4.6
 23000 -18.3  -0.9  330  32 16   8.0   4.4 | -17.7   0.1  335  26 14   8.4   4.6
 22000 -15.9   3.4  330  31 16   7.9   4.3 | -15.2   4.6  330  26 13   8.0   4.4
 21000 -13.6   7.5  330  29 15   7.6   4.2 | -13.0   8.6  330  25 13   7.2   3.9
 20000 -11.3  11.7  330  28 14   7.6   4.2 | -10.9  12.4  325  25 13   7.2   3.9
 19500 -10.2  13.6  330  27 14   7.6   4.2 |  -9.8  14.4  325  24 12   7.2   3.9
 19000  -9.0  15.8  330  26 13   7.4   4.1 |  -8.7  16.3  325  24 12   7.5   4.1
 18500  -7.9  17.8  330  25 13   7.4   4.1 |  -7.6  18.3  325  23 12   7.5   4.1
 18000  -6.8  19.8  330  23 12   7.1   3.9 |  -6.5  20.3  325  22 11   7.5   4.1
 17500  -5.8  21.6  330  22 11   6.7   3.7 |  -5.4  22.3  320  21 11   7.5   4.1
 17000  -4.9  23.2  325  21 11   6.8   3.7 |  -4.3  24.3  320  20 10   7.6   4.1
 16500  -4.0  24.8  325  20 10   6.0   3.3 |  -3.3  26.1  320  19 10   6.5   3.6
 16000  -3.1  26.4  320  18 10   6.2   3.4 |  -2.3  27.9  320  18  9   6.6   3.6
 15500  -1.8  28.8  315  16  8   6.8   3.7 |  -0.8  30.6  315  16  8   6.8   3.7
 15000  -0.8  30.6  315  14  7   6.7   3.7 |   0.1  32.2  310  15  8   7.0   3.9
 14500   0.2  32.4  315  13  6   7.9   4.3 |   1.0  33.8  305  14  7   6.6   3.6
 14000   1.3  34.3  320  11  6   7.8   4.3 |   1.9  35.4  300  11  6   6.7   3.7
 13500   2.5  36.5  325   9  5   8.2   4.5 |   2.9  37.2  295   9  5   7.2   4.0
 13000   3.7  38.7  330   8  4   8.3   4.5 |   3.9  39.0  295   7  3   7.3   4.0
 12500   4.9  40.8  340   7  4   8.7   4.8 |   5.0  41.0  295   4  2   8.2   4.5
 12000   6.3  43.3  345   6  3   8.9   4.9 |   6.4  43.5  295   3  2   8.6   4.7
 11500   7.7  45.9  350   5  2   8.7   4.8 |   7.7  45.9  290   2  1   8.7   4.8
 11000   8.9  48.0  345   3  2   8.3   4.6 |   9.0  48.2  260   2  1   8.5   4.7
 10500  10.2  50.4  335   2  1   4.8   2.6 |  10.3  50.5  235   2  1   4.0   2.2
 10250  10.4  50.7  325   1  1   5.0   2.7 |  10.5  50.9  230   2  1   5.4   3.0
 10000  11.1  52.0  295   1  1  11.2   6.1 |  11.3  52.3  225   2  1  12.8   7.0
  9750  11.8  53.2  255   1  1  11.7   6.4 |  12.2  54.0  225   2  1  12.1   6.6
  9500  12.6  54.7  235   2  1   7.8   4.3 |  12.9  55.2  220   2  1   8.1   4.4
  9250  12.9  55.2  240   2  1   4.0   2.2 |  13.3  55.9  215   2  1   4.6   2.6
  9000  13.3  55.9  245   2  1   7.9   4.4 |  13.7  56.7  205   1  1   8.3   4.5
  8750  13.9  57.0  255   1  1  10.0   5.5 |  14.3  57.7  090   1  0   9.6   5.2
  8500  14.5  58.1  275   1  1   7.7   4.2 |  14.8  58.6  060   2  1   7.5   4.1
  8250  14.9  58.8  290   2  1   6.7   3.7 |  15.1  59.2  050   3  2   6.7   3.7
  8000  15.4  59.7  300   2  1   7.6   4.2 |  15.5  59.9  050   5  2   7.8   4.3
  7750  15.8  60.4  305   3  1   4.8   2.6 |  15.9  60.6  045   5  3   9.1   5.0
  7500  15.8  60.4  315   3  2  -0.6  -0.3 |  16.5  61.7  045   6  3   9.9   5.4
  7250  15.6  60.1  330   4  2  -1.2  -0.7 |  17.2  63.0  045   6  3   9.8   5.4
  7000  15.4  59.7  345   4  2  -2.5  -1.4 |  17.9  64.2  045   6  3  10.4   5.7
  6750  15.0  59.0  355   5  3   1.5   0.8 |  18.7  65.7  045   6  3  10.7   5.9
  6500  15.4  59.7  355   5  3   6.3   3.5 |  19.5  67.1  045   6  3  10.3   5.7
  6250  15.8  60.4  360   5  3   4.8   2.6 |  20.2  68.4  040   6  3  10.1   5.5
  6000  16.1  61.0  005   6  3   6.2   3.4 |  21.0  69.8  040   6  3  11.4   6.2
  5750  16.8  62.2  005   6  3  14.0   7.7 |  22.1  71.8  040   6  3  19.2  10.5
  5500  18.2  64.8  005   6  3  24.0  13.1 |  23.9  75.0  040   6  3  28.0  15.4

           06/26/2017 at 1500 MDT          |       06/26/2017 at 1800 MDT
                                           |
K index... +26.1  LI... -2.3               | K index... +33.9  LI... -2.6
CAPE... +671.9  CIN... -38.4               | CAPE... +797.1  CIN... -10.5
                                           |
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 -63.4 -82.1  325  36 18   2.9   1.6 | -63.9 -83.0  320  36 19   2.9   1.6
 45000 -58.1 -72.6  325  45 23   4.6   2.5 | -58.2 -72.8  315  44 23   5.4   2.9
 40000 -51.4 -60.5  325  53 27   3.4   1.9 | -50.3 -58.5  315  48 25   4.1   2.3
 38000 -49.3 -56.7  320  45 23   3.4   1.9 | -47.9 -54.2  310  45 23   4.1   2.3
 36000 -47.3 -53.1  315  38 20   3.5   1.9 | -45.4 -49.7  310  41 21   4.1   2.3
 34000 -43.7 -46.7  315  33 17   6.7   3.7 | -42.2 -44.0  310  38 19   5.7   3.1
 32000 -39.7 -39.5  315  29 15   6.7   3.7 | -38.8 -37.8  305  34 18   5.7   3.1
 30000 -34.8 -30.6  320  26 13   7.6   4.2 | -34.2 -29.6  305  32 16   7.1   3.9
 29000 -32.5 -26.5  320  25 13   7.6   4.2 | -32.1 -25.8  305  31 16   7.1   3.9
 28000 -30.2 -22.4  320  24 12   8.1   4.5 | -29.9 -21.8  305  30 15   7.7   4.2
 27000 -27.7 -17.9  315  25 13   8.3   4.6 | -27.5 -17.5  305  29 15   8.0   4.4
 26000 -25.3 -13.5  315  25 13   8.3   4.6 | -25.1 -13.2  305  29 15   8.0   4.4
 25000 -22.8  -9.0  315  26 13   8.4   4.6 | -22.7  -8.9  305  28 14   8.0   4.4
 24000 -20.2  -4.4  315  26 14   8.4   4.6 | -20.3  -4.5  310  28 14   8.4   4.6
 23000 -17.7   0.1  315  26 14   8.4   4.6 | -17.8  -0.0  310  28 15   8.4   4.6
 22000 -15.2   4.6  315  26 14   8.0   4.4 | -15.3   4.5  310  29 15   8.3   4.5
 21000 -13.0   8.6  315  26 13   7.1   3.9 | -12.9   8.8  310  28 14   8.0   4.4
 20000 -10.9  12.4  315  25 13   7.1   3.9 | -10.5  13.1  310  27 14   8.1   4.4
 19500  -9.9  14.2  315  25 13   7.0   3.9 |  -9.3  15.3  310  26 13   8.1   4.5
 19000  -8.7  16.3  310  25 13   8.4   4.6 |  -8.1  17.4  305  26 13   8.2   4.5
 18500  -7.5  18.5  310  24 12   8.3   4.5 |  -6.9  19.6  305  26 13   8.2   4.5
 18000  -6.3  20.7  310  23 12   8.5   4.6 |  -5.7  21.7  305  26 13   8.1   4.5
 17500  -5.0  23.0  305  22 11   8.7   4.8 |  -4.6  23.7  300  25 13   8.1   4.4
 17000  -3.8  25.2  300  21 11   8.7   4.8 |  -3.4  25.9  300  24 12   8.4   4.6
 16500  -2.6  27.3  300  20 11   8.4   4.6 |  -2.4  27.7  295  21 11   7.0   3.9
 16000  -0.8  30.6  295  19 10   8.4   4.6 |  -1.0  30.2  285  16  8   7.5   4.1
 15500   0.3  32.5  295  18  9   7.5   4.1 |  -0.1  31.8  275  12  6   5.7   3.1
 15000   1.3  34.3  290  16  8   7.8   4.3 |   0.6  33.1  260   8  4   5.8   3.2
 14500   2.3  36.1  290  14  7   6.4   3.5 |   1.5  34.7  225   5  3   6.3   3.5
 14000   3.2  37.8  280  11  5   6.5   3.6 |   2.4  36.3  185   4  2   6.3   3.5
 13500   4.1  39.4  265   8  4   5.9   3.2 |   3.4  38.1  155   5  3   8.4   4.6
 13000   4.9  40.8  245   4  2   5.7   3.1 |   4.7  40.5  140   6  3   9.2   5.0
 12500   5.8  42.4  180   3  2   7.2   4.0 |   6.1  43.0  125   6  3   9.4   5.2
 12000   7.0  44.6  140   3  2   8.2   4.5 |   7.5  45.5  125   6  3   9.6   5.3
 11500   8.1  46.6  110   4  2   8.7   4.8 |   8.9  48.0  120   6  3   9.7   5.3
 11000   9.5  49.1  105   4  2   8.9   4.9 |  10.4  50.7  120   6  3   9.3   5.1
 10500  10.8  51.4  105   4  2   4.7   2.6 |  11.8  53.2  120   6  3   4.1   2.3
 10250  11.0  51.8  105   4  2   6.8   3.7 |  11.9  53.4  115   6  3   6.0   3.3
 10000  11.9  53.4  100   4  2  13.8   7.6 |  12.9  55.2  115   6  3  14.2   7.8
  9750  12.8  55.0  100   4  2  12.6   6.9 |  13.8  56.8  115   6  3  12.9   7.1
  9500  13.7  56.7  100   4  2   9.6   5.2 |  14.7  58.5  115   6  3   9.8   5.4
  9250  14.3  57.7  095   4  2   7.0   3.9 |  15.3  59.5  115   6  3   6.9   3.8
  9000  15.0  59.0  095   4  2  11.3   6.2 |  15.9  60.6  110   6  3  10.7   5.9
  8750  15.9  60.6  095   4  2  12.6   6.9 |  16.8  62.2  110   6  3  12.1   6.6
  8500  16.7  62.1  095   4  2  10.2   5.6 |  17.7  63.9  110   5  3  10.6   5.8
  8250  17.4  63.3  090   4  2   8.5   4.7 |  18.4  65.1  110   5  3   9.5   5.2
  8000  18.1  64.6  090   4  2   9.9   5.4 |  19.1  66.4  105   5  3  10.0   5.5
  7750  18.9  66.0  090   4  2  10.9   6.0 |  19.9  67.8  105   5  3  10.3   5.6
  7500  19.7  67.5  090   4  2  10.2   5.6 |  20.6  69.1  105   5  3  10.2   5.6
  7250  20.4  68.7  085   4  2  10.2   5.6 |  21.4  70.5  105   5  3  10.3   5.6
  7000  21.2  70.2  085   4  2   9.8   5.4 |  22.2  72.0  105   5  3   9.7   5.3
  6750  21.9  71.4  085   4  2   9.8   5.3 |  22.9  73.2  100   5  3   9.4   5.1
  6500  22.7  72.9  085   4  2  10.5   5.8 |  23.6  74.5  100   5  3  10.3   5.7
  6250  23.4  74.1  080   4  2  10.1   5.5 |  24.4  75.9  100   5  3  11.2   6.1
  6000  24.2  75.6  080   4  2  12.0   6.6 |  25.2  77.4  095   5  2   9.5   5.2
  5750  25.3  77.5  080   4  2  19.5  10.7 |  25.9  78.6  095   5  2  12.9   7.1
  5500  27.1  80.8  075   4  2  25.9  14.2 |  27.3  81.1  095   5  2  23.2  12.7
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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