Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 280016
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1816 MDT Wednesday, July 27, 2016

This forecast is for Thursday, July 28, 2016:

If the trigger temperature of 86.0 F/30.0 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 610 ft/min (3.1 m/s)
   Maximum height of thermals.................. 12747 ft MSL (7440 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1115 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................. 8966 ft MSL (3660 ft AGL)
Thermal soaring outlook for Friday 07/29....... 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)................ Weak PVA
Potential height of wave....................... 41048 ft MSL (35741 ft AGL)
Wave soaring outlook for Friday 07/29.......... Poor

Remarks... None

Sunrise/Sunset.................... 05:55:22 / 20:16:50 MDT
Total possible sunshine........... 14 hr 21 min 29 sec (861 min 29 sec)
Altitude of sun at 13:05:54 MDT... 68.95 degrees

Upper air data from numerical model forecast valid on 07/28/2016 at 0600 MDT

Freezing level.................. 16518 ft MSL (11211 ft AGL)
Convective condensation level... 16001 ft MSL (10694 ft AGL)
Lifted condensation level....... 15835 ft MSL (10529 ft AGL)
Lifted index.................... -3.2
K index......................... +15.5

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  -63.0 -81.4   295   29   15   0.9   0.5      M     M       M      M    M
 45000  -59.2 -74.6   295   48   25   5.7   3.1      M     M       M      M    M
 40000  -50.7 -59.3   295   53   27   5.3   2.9      M     M       M      M    M
 38000  -47.5 -53.5   300   53   27   5.3   2.9      M     M       M      M    M
 36000  -44.3 -47.7   300   53   27   5.2   2.9      M     M       M      M    M
 34000  -39.4 -38.9   305   50   26   7.5   4.1      M     M       M      M    M
 32000  -34.9 -30.8   310   47   24   7.7   4.2      M     M       M      M    M
 30000  -30.2 -22.4   310   41   21   7.7   4.2   45.1 113.2     9.4      M    M
 29000  -27.9 -18.2   310   38   19   7.7   4.2   44.4 111.9     9.0      M    M
 28000  -25.6 -14.1   310   35   18   7.8   4.3   43.7 110.6     8.5      M    M
 27000  -23.2  -9.8   310   35   18   7.8   4.3   42.8 109.1     8.0      M    M
 26000  -20.9  -5.6   315   34   18   7.8   4.3   42.1 107.8     7.5      M    M
 25000  -18.5  -1.3   320   34   17   7.6   4.2   41.5 106.8     7.1      M    M
 24000  -16.3   2.7   315   32   17   7.3   4.0   40.5 105.0     6.4      M    M
 23000  -14.1   6.6   315   31   16   7.3   4.0   39.7 103.4     5.7      M    M
 22000  -11.9  10.6   310   29   15   6.7   3.6   38.9 102.0     5.1      M    M
 21000  -10.1  13.8   315   28   14   6.2   3.4   37.5  99.5     4.0      M    M
 20000   -8.3  17.1   320   26   13   6.2   3.4   36.3  97.3     2.9      M    M
 19500   -7.4  18.7   320   25   13   6.3   3.5   35.7  96.3     2.4      M    M
 19000   -6.4  20.5   320   25   13   7.4   4.1   35.2  95.4     1.9      M    M
 18500   -5.4  22.3   320   25   13   7.5   4.1   34.8  94.7     1.5      M    M
 18000   -3.7  25.3   315   25   13   9.2   5.0   34.4  93.9     1.0      M    M
 17500   -2.3  27.9   315   25   13   9.1   5.0   34.3  93.7     0.9      M    M
 17000   -1.0  30.2   315   24   12   8.8   4.8   34.2  93.5     0.8      M    M
 16500    0.3  32.5   310   23   12   8.8   4.8   34.0  93.2     0.6      M    M
 16000    1.6  34.9   310   22   11   8.9   4.9   33.8  92.9     0.5      M    M
 15500    3.0  37.4   310   21   11   9.3   5.1   33.7  92.7     0.4      M    M
 15000    4.4  39.9   310   20   10   9.3   5.1   33.7  92.6     0.3      M    M
 14500    5.8  42.4   310   19   10   9.6   5.3   33.6  92.5     0.3      M    M
 14000    7.3  45.1   310   18    9   9.6   5.3   33.6  92.4     0.3      M    M
 13500    8.7  47.7   310   17    9   8.9   4.9   33.5  92.3     0.2      M    M
 13000   10.0  50.0   310   16    8   8.8   4.8   33.4  92.0     0.1      M    M
 12500   11.3  52.3   305   16    8   8.3   4.5   33.2  91.8    -0.1    579  2.9
 12000   12.4  54.3   300   15    7   7.9   4.3   32.9  91.2    -0.4    529  2.7
 11500   13.6  56.5   295   14    7   7.6   4.2   32.6  90.7    -0.7    479  2.4
 11000   14.6  58.3   285   13    7   7.0   3.9   32.2  90.0    -1.2    434  2.2
 10500   15.6  60.1   275   13    6   3.4   1.9   31.8  89.3    -1.6    389  2.0
 10250   15.7  60.3   275   12    6   5.3   2.9   31.2  88.2    -2.3    379  1.9
 10000   16.4  61.5   265   12    6  11.4   6.3   31.2  88.2    -2.3    351  1.8
  9750   17.1  62.8   260   12    6  10.6   5.8   31.3  88.3    -2.4    323  1.6
  9500   17.8  64.0   250   13    6   8.4   4.6   31.3  88.4    -2.4    295  1.5
  9250   18.2  64.8   245   13    7   5.9   3.2   31.0  87.9    -2.7    275  1.4
  9000   18.7  65.7   240   13    7   8.1   4.4   30.8  87.5    -3.0    253  1.3
  8750   19.3  66.7   240   13    7   9.0   4.9   30.7  87.3    -3.1    228  1.2
  8500   19.9  67.8   235   14    7   7.8   4.3   30.7  87.2    -3.3    203  1.0
  8250   20.3  68.5   230   14    7   7.0   3.8   30.5  86.8    -3.5    181  0.9
  8000   20.8  69.4   230   13    7   7.0   3.8   30.3  86.5    -3.8    159  0.8
  7750   21.3  70.3   230   13    7   6.4   3.5   30.0  86.0    -4.1    138  0.7
  7500   21.7  71.1   225   13    7   5.1   2.8   29.7  85.5    -4.4    118  0.6
  7250   22.0  71.6   225   12    6   4.1   2.3   29.3  84.7    -4.9    102  0.5
  7000   22.3  72.1   225   12    6   4.7   2.6   28.9  84.0    -5.3     86  0.4
  6750   22.5  72.5   225   11    6   2.1   1.1   28.5  83.2    -5.8     71  0.4
  6500   22.5  72.5   225   10    5  -1.4  -0.8   27.7  81.9    -6.6     64  0.3
  6250   22.3  72.1   230    9    5  -3.4  -1.9   26.8  80.2    -7.5     63  0.3
  6000   22.1  71.8   235    8    4   1.8   1.0   25.9  78.6    -8.5     62  0.3
  5750   22.2  72.0   240    7    3  -4.6  -2.5   25.3  77.6    -9.1     50  0.3
  5500   20.8  69.4   230    5    3 -29.5 -16.2   23.3  73.9   -11.2     84  0.4

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

           07/28/2016 at 0900 MDT          |       07/28/2016 at 1200 MDT
                                           |
K index... +12.2  LI... -1.8               | K index... +12.8  LI... -5.3
CAPE... +111.0  CIN... -223.7              | CAPE... +1388.9  CIN... -63.4
                                           |
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  295  27 14   1.8   1.0 | -61.5 -78.7  295  29 15   2.0   1.1
 45000 -58.3 -72.9  300  45 23   4.7   2.6 | -57.6 -71.7  295  46 24   3.8   2.1
 40000 -51.1 -60.0  295  55 28   5.3   2.9 | -51.6 -60.9  295  60 31   5.5   3.0
 38000 -48.0 -54.4  295  55 29   5.3   2.9 | -48.3 -54.9  295  56 29   5.5   3.0
 36000 -44.8 -48.6  295  56 29   5.1   2.8 | -44.9 -48.8  295  52 27   5.3   2.9
 34000 -39.8 -39.6  300  52 27   7.6   4.2 | -40.0 -40.0  290  51 26   7.5   4.1
 32000 -35.2 -31.4  300  48 25   7.9   4.3 | -35.5 -31.9  290  51 26   7.7   4.3
 30000 -30.5 -22.9  295  42 22   7.9   4.3 | -30.8 -23.4  290  48 25   7.7   4.2
 29000 -28.1 -18.6  295  39 20   7.9   4.3 | -28.5 -19.3  290  46 24   7.7   4.2
 28000 -25.8 -14.4  295  36 18   7.5   4.1 | -26.2 -15.2  290  45 23   7.9   4.3
 27000 -23.5 -10.3  295  35 18   7.6   4.2 | -23.8 -10.8  290  44 22   7.9   4.3
 26000 -21.2  -6.2  295  35 18   7.6   4.2 | -21.5  -6.7  290  43 22   7.9   4.3
 25000 -19.0  -2.2  300  34 18   7.5   4.1 | -19.1  -2.4  290  42 21   6.9   3.8
 24000 -16.7   1.9  300  31 16   7.4   4.0 | -17.4   0.7  295  37 19   5.6   3.1
 23000 -14.5   5.9  305  28 15   7.4   4.0 | -15.7   3.7  300  32 16   5.6   3.1
 22000 -12.4   9.7  305  26 13   5.9   3.3 | -14.0   6.8  305  28 14   6.7   3.7
 21000 -10.9  12.4  310  24 12   5.0   2.7 | -11.8  10.8  305  24 12   7.6   4.2
 20000  -9.5  14.9  320  22 11   5.3   2.9 |  -9.6  14.7  300  20 10   7.8   4.3
 19500  -8.8  16.2  320  21 11   5.7   3.1 |  -8.5  16.7  295  19 10   7.9   4.3
 19000  -7.6  18.3  320  21 11   9.7   5.3 |  -7.2  19.0  295  18  9   8.9   4.9
 18500  -6.3  20.7  320  20 10   9.4   5.2 |  -6.0  21.2  295  17  9   8.8   4.8
 18000  -4.9  23.2  320  19 10   9.4   5.1 |  -4.0  24.8  295  17  9   9.2   5.0
 17500  -2.8  27.0  315  20 10   9.3   5.1 |  -2.6  27.3  295  17  9   9.2   5.0
 17000  -1.4  29.5  310  20 10   9.6   5.3 |  -1.3  29.7  300  17  9   9.1   5.0
 16500   0.0  32.0  310  20 10   9.7   5.3 |   0.1  32.2  300  17  9   9.1   5.0
 16000   1.5  34.7  310  20 10   9.7   5.3 |   1.4  34.5  300  17  9   9.1   5.0
 15500   2.9  37.2  310  20 10   9.6   5.3 |   2.8  37.0  300  17  9   9.1   5.0
 15000   4.4  39.9  310  19 10   9.6   5.3 |   4.1  39.4  305  17  9   9.1   5.0
 14500   5.8  42.4  310  19 10   9.6   5.3 |   5.5  41.9  305  17  9   9.5   5.2
 14000   7.2  45.0  310  18  9   9.6   5.3 |   6.9  44.4  305  17  9   9.5   5.2
 13500   8.6  47.5  310  17  9   9.2   5.1 |   8.3  46.9  310  16  8   9.1   5.0
 13000  10.0  50.0  310  17  9   9.2   5.0 |   9.7  49.5  310  16  8   9.1   5.0
 12500  11.4  52.5  310  16  8   9.4   5.2 |  11.0  51.8  310  15  8   9.2   5.0
 12000  12.8  55.0  310  16  8   9.5   5.2 |  12.4  54.3  315  14  7   9.2   5.1
 11500  14.3  57.7  310  15  8   9.1   5.0 |  13.8  56.8  315  14  7   9.1   5.0
 11000  15.6  60.1  310  15  8   8.4   4.6 |  15.1  59.2  320  13  7   8.8   4.8
 10500  16.9  62.4  305  14  7   4.1   2.3 |  16.5  61.7  320  12  6   4.0   2.2
 10250  17.0  62.6  305  14  7   5.3   2.9 |  16.6  61.9  320  12  6   5.4   3.0
 10000  17.8  64.0  305  14  7  11.7   6.4 |  17.4  63.3  325  12  6  12.6   6.9
  9750  18.6  65.5  300  13  7  10.7   5.9 |  18.3  64.9  325  12  6  11.6   6.3
  9500  19.3  66.7  295  13  7   8.4   4.6 |  19.1  66.4  325  12  6   8.4   4.6
  9250  19.8  67.6  295  13  6   6.0   3.3 |  19.5  67.1  325  12  6   5.6   3.1
  9000  20.3  68.5  295  12  6   8.1   4.4 |  20.1  68.2  330  12  6   8.5   4.7
  8750  20.9  69.6  290  12  6   8.7   4.8 |  20.7  69.3  330  12  6   9.3   5.1
  8500  21.5  70.7  290  11  6   7.5   4.1 |  21.3  70.3  330  12  6   6.7   3.7
  8250  21.9  71.4  285  11  6   6.8   3.7 |  21.7  71.1  335  11  6   4.6   2.5
  8000  22.4  72.3  285  10  5   6.7   3.7 |  22.0  71.6  335  11  6   5.0   2.7
  7750  22.8  73.0  285  10  5   6.0   3.3 |  22.4  72.3  340  11  5   4.5   2.5
  7500  23.2  73.8  280  10  5   4.8   2.6 |  22.6  72.7  345  10  5   4.5   2.5
  7250  23.4  74.1  280   9  5   3.8   2.1 |  22.7  72.9  350   9  5   4.9   2.7
  7000  23.7  74.7  275   8  4   5.0   2.7 |  22.8  73.0  360   8  4   6.5   3.5
  6750  24.0  75.2  275   7  4   4.0   2.2 |  23.1  73.6  010   8  4   9.5   5.2
  6500  24.0  75.2  280   6  3  -0.2  -0.1 |  23.8  74.8  015   8  4  11.0   6.0
  6250  23.9  75.0  290   5  2   0.2   0.1 |  24.6  76.3  015   8  4  11.6   6.4
  6000  23.8  74.8  305   4  2  -4.9  -2.7 |  25.4  77.7  015   8  4   8.9   4.9
  5750  23.3  73.9  345   3  1   2.5   1.4 |  26.1  79.0  015   8  4  15.3   8.4
  5500  24.5  76.1  345   3  1  30.9  17.0 |  28.0  82.4  015   8  4  33.7  18.5

           07/28/2016 at 1500 MDT          |       07/28/2016 at 1800 MDT
                                           |
K index... +20.9  LI... -3.7               | K index... +22.7  LI... -2.6
CAPE... +932.1  CIN... -21.4               | CAPE... +792.0  CIN... -31.1
                                           |
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 -61.2 -78.2  270  21 11   2.0   1.1 | -61.5 -78.7  270  19 10   1.2   0.6
 45000 -57.2 -71.0  280  36 18   3.9   2.1 | -58.3 -72.9  280  31 16   4.0   2.2
 40000 -51.1 -60.0  295  62 32   5.2   2.8 | -51.9 -61.4  300  45 23   5.8   3.2
 38000 -48.0 -54.4  295  56 29   5.2   2.8 | -48.4 -55.1  300  42 22   5.8   3.2
 36000 -44.9 -48.8  295  50 26   4.9   2.7 | -44.9 -48.8  305  40 20   5.7   3.1
 34000 -40.0 -40.0  295  45 23   7.6   4.2 | -39.9 -39.8  305  36 19   7.6   4.2
 32000 -35.4 -31.7  295  41 21   7.7   4.2 | -35.4 -31.7  305  34 17   7.8   4.3
 30000 -31.0 -23.8  300  40 21   7.4   4.0 | -30.6 -23.1  305  33 17   8.0   4.4
 29000 -28.8 -19.8  300  40 21   7.3   4.0 | -28.2 -18.8  305  33 17   8.0   4.4
 28000 -26.5 -15.7  300  40 20   7.8   4.3 | -25.8 -14.4  305  33 17   7.2   4.0
 27000 -24.2 -11.6  295  40 20   7.8   4.3 | -23.6 -10.5  305  33 17   7.3   4.0
 26000 -21.9  -7.4  295  40 20   7.8   4.3 | -21.4  -6.5  305  33 17   7.3   4.0
 25000 -19.5  -3.1  290  40 21   7.2   4.0 | -19.3  -2.7  305  33 17   7.1   3.9
 24000 -17.6   0.3  295  38 19   6.4   3.5 | -17.2   1.0  300  34 18   6.9   3.8
 23000 -15.7   3.7  295  36 18   6.5   3.6 | -15.1   4.8  300  36 18   6.9   3.8
 22000 -13.8   7.2  295  34 17   7.2   4.0 | -13.1   8.4  295  37 19   7.5   4.1
 21000 -11.5  11.3  295  31 16   7.8   4.3 | -10.8  12.6  295  35 18   8.0   4.4
 20000  -9.2  15.4  295  29 15   7.9   4.3 |  -8.4  16.9  295  34 17   8.1   4.4
 19500  -8.1  17.4  290  28 14   8.0   4.4 |  -7.3  18.9  300  33 17   8.2   4.5
 19000  -6.8  19.8  290  27 14   9.3   5.1 |  -6.0  21.2  295  32 17   9.2   5.0
 18500  -5.4  22.3  290  27 14   9.3   5.1 |  -4.6  23.7  295  32 16   9.1   5.0
 18000  -3.4  25.9  290  26 13   9.4   5.1 |  -3.3  26.1  295  31 16   9.0   4.9
 17500  -2.0  28.4  285  25 13   9.4   5.1 |  -1.3  29.7  295  30 15   8.9   4.9
 17000  -0.6  30.9  285  25 13   9.1   5.0 |   0.0  32.0  295  29 15   9.0   4.9
 16500   0.7  33.3  285  24 12   9.1   5.0 |   1.3  34.3  295  28 14   9.0   4.9
 16000   2.0  35.6  285  23 12   9.1   5.0 |   2.6  36.7  295  27 14   9.1   5.0
 15500   3.4  38.1  285  22 11   9.1   5.0 |   4.0  39.2  295  25 13   9.5   5.2
 15000   4.7  40.5  285  21 11   9.1   5.0 |   5.4  41.7  295  24 12   9.6   5.3
 14500   6.1  43.0  285  19 10   9.4   5.1 |   6.8  44.2  295  22 11   8.9   4.9
 14000   7.5  45.5  285  18  9   9.4   5.1 |   8.1  46.6  295  21 11   8.9   4.9
 13500   8.8  47.8  285  16  8   8.9   4.9 |   9.4  48.9  295  19 10   8.9   4.9
 13000  10.1  50.2  285  14  7   8.9   4.9 |  10.7  51.3  295  16  8   8.9   4.9
 12500  11.5  52.7  285  12  6   8.8   4.8 |  12.0  53.6  295  14  7   8.5   4.7
 12000  12.8  55.0  285  10  5   8.7   4.8 |  13.2  55.8  295  11  5   8.3   4.5
 11500  14.1  57.4  285   8  4   8.2   4.5 |  14.4  57.9  290   8  4   8.0   4.4
 11000  15.2  59.4  295   5  3   7.5   4.1 |  15.4  59.7  300   5  3   7.5   4.1
 10500  16.4  61.5  320   3  2   4.7   2.6 |  16.5  61.7  325   3  2   4.6   2.5
 10250  16.6  61.9  325   3  2   6.0   3.3 |  16.7  62.1  330   3  2   6.1   3.3
 10000  17.2  63.0  355   3  2  10.7   5.9 |  17.4  63.3  340   3  2  11.1   6.1
  9750  17.8  64.0  015   4  2  10.1   5.5 |  18.1  64.6  350   3  2  10.1   5.5
  9500  18.4  65.1  030   5  3   9.1   5.0 |  18.8  65.8  360   3  2   9.4   5.2
  9250  19.0  66.2  030   5  3   8.6   4.7 |  19.5  67.1  360   3  2   9.1   5.0
  9000  19.7  67.5  030   6  3  10.6   5.8 |  20.2  68.4  360   3  2  10.6   5.8
  8750  20.5  68.9  035   6  3  11.0   6.0 |  21.0  69.8  360   4  2  10.9   6.0
  8500  21.2  70.2  035   6  3  10.2   5.6 |  21.8  71.2  360   4  2  10.3   5.6
  8250  22.0  71.6  030   6  3   9.5   5.2 |  22.5  72.5  360   4  2   9.6   5.3
  8000  22.7  72.9  030   6  3  10.0   5.5 |  23.3  73.9  360   4  2  10.0   5.5
  7750  23.5  74.3  030   6  3  10.4   5.7 |  24.0  75.2  360   4  2  10.3   5.7
  7500  24.2  75.6  030   6  3  10.4   5.7 |  24.8  76.6  360   4  2   9.9   5.4
  7250  25.0  77.0  030   6  3  10.6   5.8 |  25.5  77.9  360   4  2   9.6   5.3
  7000  25.7  78.3  030   6  3  10.1   5.5 |  26.3  79.3  360   4  2   9.8   5.4
  6750  26.5  79.7  030   6  3   9.7   5.3 |  27.0  80.6  360   4  2  10.2   5.6
  6500  27.2  81.0  030   6  3  10.5   5.8 |  27.8  82.0  360   4  2  10.4   5.7
  6250  28.1  82.6  030   6  3  11.9   6.5 |  28.5  83.3  360   4  2  10.8   5.9
  6000  28.9  84.0  030   6  3   8.5   4.7 |  29.3  84.7  360   4  2   9.6   5.3
  5750  29.6  85.3  025   6  3  13.9   7.6 |  30.0  86.0  360   4  2  12.0   6.6
  5500  31.3  88.3  025   6  3  33.0  18.1 |  31.2  88.2  360   4  2  20.4  11.2
________________________________________________________________________________

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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