Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 080035
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1835 MDT Monday, July 7, 2014

This forecast is for Tuesday, July 8, 2014:

If the trigger temperature of 68.9 F/20.5 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 477 ft/min (2.4 m/s)
   Maximum height of thermals.................. 12559 ft MSL (7272 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 0815 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................. 11046 ft MSL (5758 ft AGL)
Thermal soaring outlook for Wednesday 07/09.... Excellent

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 13168 ft MSL (7881 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18339 ft MSL (13052 ft AGL)
Wave soaring outlook for Wednesday 07/09....... Poor

Remarks... None

Sunrise/Sunset.................... 05:39:14 / 20:29:58 MDT
Total possible sunshine........... 14 hr 50 min 44 sec (890 min 44 sec)
Altitude of sun at 13:04:35 MDT... 72.61 degrees

Upper air data from numerical model forecast valid on 07/08/2014 at 0600 MDT

Freezing level.................. 16280 ft MSL (10993 ft AGL)
Convective condensation level... 9055 ft MSL (3768 ft AGL)
Lifted condensation level....... 11938 ft MSL (6651 ft AGL)
Lifted index.................... -3.8
K index......................... +21.9

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  -66.5 -87.7   300   26   13   0.5   0.3      M     M       M      M    M
 45000  -62.8 -81.0   300   32   16   6.4   3.5      M     M       M      M    M
 40000  -53.0 -63.4   315   28   15   7.5   4.1      M     M       M      M    M
 38000  -48.5 -55.3   315   27   14   7.5   4.1      M     M       M      M    M
 36000  -44.0 -47.2   310   25   13   7.5   4.1      M     M       M      M    M
 34000  -39.2 -38.6   315   25   13   8.1   4.4      M     M       M      M    M
 32000  -33.7 -28.7   320   25   13   8.0   4.4      M     M       M      M    M
 30000  -29.4 -20.9   320   24   12   7.1   3.9   46.7 116.0    14.9      M    M
 29000  -27.3 -17.1   315   24   12   7.1   3.9   45.7 114.3    14.3      M    M
 28000  -25.2 -13.4   315   24   12   7.1   3.9   44.8 112.6    13.7      M    M
 27000  -23.0  -9.4   315   24   12   7.1   3.9   43.6 110.6    13.0      M    M
 26000  -20.9  -5.6   315   25   13   7.1   3.9   42.6 108.8    12.3      M    M
 25000  -18.8  -1.8   315   26   13   7.0   3.9   41.8 107.2    11.7      M    M
 24000  -16.7   1.9   310   26   13   7.0   3.9   40.6 105.2    11.0      M    M
 23000  -14.6   5.7   310   26   13   7.0   3.9   39.7 103.4    10.3      M    M
 22000  -12.5   9.5   310   26   14   6.8   3.7   38.8 101.8     9.6      M    M
 21000  -10.6  12.9   305   26   13   6.6   3.6   37.6  99.6     8.7      M    M
 20000   -8.6  16.5   305   26   13   6.7   3.7   36.5  97.7     7.8      M    M
 19500   -7.7  18.1   300   25   13   6.7   3.7   36.0  96.8     7.4      M    M
 19000   -6.7  19.9   300   26   13   7.1   3.9   35.5  95.9     7.0      M    M
 18500   -5.7  21.7   300   27   14   7.2   4.0   35.0  95.1     6.5      M    M
 18000   -4.7  23.5   305   28   14   7.9   4.3   34.6  94.3     6.1      M    M
 17500   -3.5  25.7   300   27   14   8.4   4.6   34.4  93.9     5.9      M    M
 17000   -2.3  27.9   300   27   14   8.5   4.7   34.2  93.5     5.6      M    M
 16500   -1.0  30.2   300   26   13   9.5   5.2   34.0  93.3     5.5      M    M
 16000    0.4  32.7   295   25   13   9.5   5.2   34.0  93.2     5.5      M    M
 15500    2.5  36.5   295   23   12   9.0   4.9   33.9  92.9     5.4      M    M
 15000    3.8  38.8   295   22   12   9.4   5.2   33.7  92.7     5.2      M    M
 14500    4.9  40.8   295   21   11   4.7   2.6   33.3  92.0     4.9      M    M
 14000    5.5  41.9   290   18    9   5.0   2.7   32.5  90.5     4.1      M    M
 13500    6.0  42.8   285   15    8   0.3   0.2   31.5  88.7     3.1      M    M
 13000    5.6  42.1   275   12    6  -1.0  -0.5   29.7  85.5     1.3      M    M
 12500    5.3  41.5   255    9    4   1.7   0.9   28.0  82.4    -0.4    476  2.4
 12000    5.8  42.4   240    6    3   3.8   2.1   27.0  80.6    -1.5    448  2.3
 11500    6.2  43.2   215    5    3   5.3   2.9   26.1  79.0    -2.5    420  2.1
 11000    7.1  44.8   185    4    2   6.4   3.5   25.6  78.0    -3.1    378  1.9
 10500    8.0  46.4   150    5    2   3.8   2.1   25.1  77.2    -3.7    336  1.7
 10250    8.1  46.6   145    5    3   0.7   0.4   24.4  76.0    -4.3    325  1.7
 10000    8.3  46.9   135    6    3   2.3   1.3   23.8  74.8    -4.9    314  1.6
  9750    8.4  47.1   130    7    4   2.2   1.2   23.2  73.8    -5.5    302  1.5
  9500    8.6  47.5   125    8    4   2.8   1.5   22.6  72.7    -6.0    290  1.5
  9250    8.8  47.8   120    8    4   2.6   1.5   22.1  71.8    -6.6    275  1.4
  9000    9.1  48.4   120    7    4   5.1   2.8   21.6  70.9    -7.0    260  1.3
  8750    9.6  49.3   115    7    3   7.5   4.1   21.4  70.5    -7.3    238  1.2
  8500   10.1  50.2   110    6    3   6.8   3.7   21.2  70.1    -7.5    215  1.1
  8250   10.5  50.9   105    5    2   6.7   3.7   21.0  69.7    -7.8    194  1.0
  8000   11.0  51.8   100    4    2   7.7   4.2   20.7  69.3    -8.1    172  0.9
  7750   11.6  52.9   085    3    2   9.4   5.2   20.7  69.2    -8.2    147  0.7
  7500   12.3  54.1   075    3    1   9.5   5.2   20.6  69.2    -8.3    119  0.6
  7250   13.0  55.4   070    3    1   9.2   5.1   20.6  69.1    -8.4     91  0.5
  7000   13.7  56.7   060    3    1   9.7   5.3   20.6  69.1    -8.4     63  0.3
  6750   14.4  57.9   055    3    2  10.1   5.5   20.6  69.1    -8.4     33  0.2
  6500   15.1  59.2   050    3    2   9.9   5.4   20.6  69.1    -8.4      4  0.0
  6250   15.9  60.6   045    3    2  10.0   5.5   20.6  69.2    -8.4      M    M
  6000   16.6  61.9   040    3    2   9.6   5.2   20.7  69.2    -8.4      M    M
  5750   17.3  63.1   040    3    2  10.2   5.6   20.7  69.2    -8.4      M    M
  5500   18.2  64.8   040    3    2  12.6   6.9   20.8  69.5    -8.3      M    M

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

           07/08/2014 at 0900 MDT          |       07/08/2014 at 1200 MDT
                                           |
K index... +21.5  LI... -1.0               | K index... +22.4  LI... -1.7
CAPE... +101.1  CIN... -110.5              | CAPE... +354.0  CIN... -106.9
                                           |
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 -66.1 -87.0  310  23 12   0.1   0.1 | -65.6 -86.1  310  22 11   0.4   0.2
 45000 -63.1 -81.6  300  31 16   6.0   3.3 | -62.5 -80.5  300  30 15   5.5   3.0
 40000 -53.6 -64.5  305  27 14   7.8   4.3 | -53.8 -64.8  300  25 13   7.5   4.1
 38000 -49.0 -56.2  300  27 14   7.8   4.3 | -49.3 -56.7  295  26 13   7.5   4.1
 36000 -44.3 -47.7  295  26 13   7.8   4.3 | -44.8 -48.6  295  26 13   7.5   4.1
 34000 -39.5 -39.1  300  24 13   8.0   4.4 | -40.0 -40.0  290  25 13   8.0   4.4
 32000 -34.1 -29.4  305  22 11   7.9   4.3 | -34.6 -30.3  285  24 12   8.0   4.4
 30000 -29.7 -21.5  305  23 12   7.3   4.0 | -30.0 -22.0  290  23 12   7.8   4.3
 29000 -27.5 -17.5  305  23 12   7.3   4.0 | -27.6 -17.7  290  23 12   7.8   4.3
 28000 -25.3 -13.5  310  23 12   7.3   4.0 | -25.3 -13.5  295  23 12   7.3   4.0
 27000 -23.1  -9.6  310  24 12   7.3   4.0 | -23.1  -9.6  300  23 12   7.3   4.0
 26000 -20.9  -5.6  315  25 13   7.3   4.0 | -20.9  -5.6  305  23 12   7.3   4.0
 25000 -18.8  -1.8  315  25 13   7.2   4.0 | -18.7  -1.7  310  23 12   7.3   4.0
 24000 -16.6   2.1  315  26 13   7.1   3.9 | -16.5   2.3  310  24 12   7.4   4.0
 23000 -14.5   5.9  315  27 14   7.1   3.9 | -14.3   6.3  315  25 13   7.4   4.0
 22000 -12.4   9.7  315  27 14   6.6   3.6 | -12.1  10.2  315  26 14   6.8   3.7
 21000 -10.6  12.9  310  27 14   6.3   3.5 | -10.2  13.6  315  27 14   6.4   3.5
 20000  -8.7  16.3  305  28 14   6.4   3.5 |  -8.4  16.9  315  28 15   6.5   3.5
 19500  -7.8  18.0  305  28 14   6.4   3.5 |  -7.4  18.7  310  29 15   6.5   3.6
 19000  -6.9  19.6  300  28 14   6.6   3.6 |  -6.5  20.3  310  29 15   6.9   3.8
 18500  -6.0  21.2  300  28 15   6.8   3.7 |  -5.5  22.1  310  30 15   7.0   3.8
 18000  -5.0  23.0  300  29 15   8.1   4.4 |  -4.5  23.9  310  30 15   7.8   4.3
 17500  -3.8  25.2  300  28 14   8.9   4.9 |  -3.3  26.1  310  30 15   8.3   4.5
 17000  -2.5  27.5  300  27 14   9.0   5.0 |  -2.2  28.0  305  29 15   8.4   4.6
 16500  -1.1  30.0  300  27 14   9.6   5.3 |  -0.2  31.6  305  28 14   9.3   5.1
 16000   1.0  33.8  300  26 14   9.4   5.1 |   1.2  34.2  305  27 14   9.2   5.1
 15500   2.3  36.1  300  25 13   8.5   4.7 |   2.5  36.5  305  26 13   8.8   4.8
 15000   3.6  38.5  295  23 12   8.9   4.9 |   3.8  38.8  305  25 13   9.2   5.0
 14500   4.6  40.3  295  20 10   5.4   3.0 |   4.9  40.8  305  23 12   6.0   3.3
 14000   5.4  41.7  290  18  9   5.9   3.2 |   5.8  42.4  300  21 11   6.4   3.5
 13500   6.0  42.8  280  16  8   1.5   0.8 |   6.6  43.9  295  19 10   4.2   2.3
 13000   5.9  42.6  270  15  8   0.6   0.3 |   7.0  44.6  285  17  9   3.9   2.1
 12500   5.9  42.6  255  14  7   0.4   0.2 |   7.5  45.5  275  15  8   3.3   1.8
 12000   5.8  42.4  240  13  7   0.5   0.3 |   7.9  46.2  255  16  8   3.1   1.7
 11500   5.8  42.4  225  13  7   3.0   1.7 |   8.2  46.8  245  17  9   3.0   1.7
 11000   6.5  43.7  215  12  6   5.0   2.8 |   8.5  47.3  230  18  9   2.9   1.6
 10500   7.2  45.0  210  12  6   4.0   2.2 |   8.9  48.0  215  20 10   1.9   1.0
 10250   7.4  45.3  205  11  6   3.9   2.1 |   9.0  48.2  215  19 10   3.9   2.2
 10000   7.8  46.0  200  11  6   5.8   3.2 |   9.4  48.9  215  18  9   7.9   4.3
  9750   8.2  46.8  185  11  6   6.1   3.3 |  10.0  50.0  210  17  9   8.1   4.4
  9500   8.6  47.5  180  11  6   6.0   3.3 |  10.5  50.9  205  17  9   5.1   2.8
  9250   9.0  48.2  180  10  5   5.7   3.1 |  10.7  51.3  200  15  8   2.6   1.5
  9000   9.5  49.1  175  10  5   6.8   3.7 |  11.0  51.8  190  13  7   4.5   2.5
  8750  10.0  50.0  175   9  4   7.3   4.0 |  11.3  52.3  175  11  6   5.8   3.2
  8500  10.5  50.9  175   8  4   6.0   3.3 |  11.7  53.1  165  11  5   7.2   4.0
  8250  10.9  51.6  170   7  3   5.8   3.2 |  12.3  54.1  160  10  5   7.5   4.1
  8000  11.3  52.3  165   6  3   5.3   2.9 |  12.9  55.2  150  10  5   9.3   5.1
  7750  11.7  53.1  155   4  2   7.3   4.0 |  13.6  56.5  150  10  5  11.1   6.1
  7500  12.3  54.1  150   4  2   9.9   5.4 |  14.4  57.9  150  10  5   9.9   5.4
  7250  13.0  55.4  145   4  2   9.6   5.3 |  15.1  59.2  150  10  5   9.4   5.1
  7000  13.8  56.8  140   4  2  10.3   5.7 |  15.9  60.6  145  10  5  10.7   5.9
  6750  14.6  58.3  135   4  2  10.5   5.8 |  16.7  62.1  145  10  5  11.1   6.1
  6500  15.3  59.5  135   4  2   9.9   5.5 |  17.5  63.5  145  10  5  10.2   5.6
  6250  16.1  61.0  135   4  2  10.0   5.5 |  18.3  64.9  145  10  5  10.1   5.5
  6000  16.8  62.2  130   4  2  10.4   5.7 |  19.0  66.2  145  10  5  11.3   6.2
  5750  17.7  63.9  130   4  2  13.4   7.4 |  20.1  68.2  145  10  5  19.0  10.4
  5500  18.8  65.8  130   4  2  16.8   9.2 |  21.9  71.4  145   9  5  27.4  15.0

           07/08/2014 at 1500 MDT          |       07/08/2014 at 1800 MDT
                                           |
K index... +27.1  LI... -2.5               | K index... +30.9  LI... -3.5
CAPE... +815.6  CIN... -88.6               | CAPE... +848.8  CIN... -0.1
                                           |
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 -65.9 -86.6  310  23 12   0.5   0.2 | -65.5 -85.9  330  24 12  -0.6  -0.3
 45000 -62.5 -80.5  295  30 16   6.0   3.3 | -63.2 -81.8  300  31 16   6.2   3.4
 40000 -53.1 -63.6  280  30 16   7.6   4.1 | -53.5 -64.3  265  43 22   8.1   4.4
 38000 -48.6 -55.5  280  29 15   7.6   4.2 | -48.6 -55.5  270  41 21   8.1   4.4
 36000 -44.0 -47.2  285  29 15   7.6   4.2 | -43.8 -46.8  275  39 20   8.1   4.4
 34000 -39.1 -38.4  280  28 14   7.2   3.9 | -38.5 -37.3  280  35 18   7.7   4.2
 32000 -34.8 -30.6  280  27 14   7.4   4.0 | -33.9 -29.0  285  32 16   8.0   4.4
 30000 -30.3 -22.5  285  26 13   7.6   4.1 | -29.5 -21.1  295  27 14   7.4   4.1
 29000 -28.0 -18.4  285  25 13   7.6   4.1 | -27.3 -17.1  300  25 13   7.4   4.1
 28000 -25.7 -14.3  290  24 12   7.7   4.2 | -25.0 -13.0  305  24 12   7.5   4.1
 27000 -23.4 -10.1  290  23 12   7.7   4.2 | -22.8  -9.0  310  24 12   7.5   4.1
 26000 -21.1  -6.0  295  22 12   7.7   4.2 | -20.6  -5.1  315  25 13   7.5   4.1
 25000 -18.8  -1.8  300  22 11   7.6   4.2 | -18.3  -0.9  315  25 13   7.3   4.0
 24000 -16.5   2.3  300  22 11   7.5   4.1 | -16.2   2.8  320  26 14   7.0   3.9
 23000 -14.3   6.3  305  23 12   7.5   4.1 | -14.1   6.6  325  28 14   7.0   3.9
 22000 -12.0  10.4  310  24 12   7.4   4.0 | -12.0  10.4  325  30 15   6.7   3.7
 21000  -9.9  14.2  310  25 13   7.3   4.0 | -10.2  13.6  325  29 15   6.4   3.5
 20000  -7.7  18.1  310  27 14   7.3   4.0 |  -8.3  17.1  325  29 15   6.4   3.5
 19500  -6.6  20.1  310  27 14   7.3   4.0 |  -7.4  18.7  320  29 15   6.5   3.5
 19000  -5.6  21.9  310  28 14   6.9   3.8 |  -6.4  20.5  320  28 15   7.1   3.9
 18500  -4.6  23.7  310  28 15   7.0   3.8 |  -5.5  22.1  320  27 14   7.2   3.9
 18000  -3.6  25.5  310  28 15   7.2   4.0 |  -4.5  23.9  315  25 13   7.1   3.9
 17500  -2.6  27.3  310  28 14   7.4   4.1 |  -3.5  25.7  315  23 12   7.0   3.8
 17000  -1.5  29.3  305  28 14   7.7   4.2 |  -2.0  28.4  315  20 10   6.9   3.8
 16500   0.2  32.4  305  26 14   8.7   4.8 |  -1.0  30.2  315  18  9   6.9   3.8
 16000   1.4  34.5  305  25 13   8.8   4.8 |  -0.0  32.0  315  16  8   6.8   3.7
 15500   2.7  36.9  305  24 12   8.6   4.7 |   1.0  33.8  315  14  7   6.5   3.6
 15000   3.9  39.0  305  23 12   8.7   4.8 |   1.9  35.4  315  11  6   6.5   3.6
 14500   5.1  41.2  305  21 11   8.2   4.5 |   2.9  37.2  315   9  5   6.2   3.4
 14000   6.3  43.3  310  20 10   8.4   4.6 |   3.8  38.8  320   7  4   6.3   3.4
 13500   7.4  45.3  310  18  9   6.7   3.7 |   4.7  40.5  325   5  3   6.4   3.5
 13000   8.3  46.9  315  16  8   6.4   3.5 |   5.6  42.1  305   4  2   6.5   3.6
 12500   9.2  48.6  315  14  7   5.6   3.1 |   6.5  43.7  270   3  1   6.4   3.5
 12000   9.9  49.8  310  12  6   5.1   2.8 |   7.4  45.3  210   5  3   6.4   3.5
 11500  10.6  51.1  310  11  5   2.9   1.6 |   8.2  46.8  195   9  5   8.1   4.4
 11000  10.6  51.1  285   6  3   0.7   0.4 |   9.5  49.1  195  10  5   9.1   5.0
 10500  10.5  50.9  230   5  2  -0.4  -0.2 |  10.8  51.4  190  10  5   4.3   2.3
 10250  10.5  50.9  215   4  2   2.9   1.6 |  11.0  51.8  190  10  5   6.5   3.6
 10000  10.9  51.6  190   5  3   6.9   3.8 |  11.9  53.4  190  10  5  13.9   7.6
  9750  11.3  52.3  170   7  3   5.8   3.2 |  12.8  55.0  185  10  5  12.2   6.7
  9500  11.7  53.1  160   8  4   7.0   3.9 |  13.6  56.5  185  10  5   9.4   5.2
  9250  12.3  54.1  160   8  4   8.3   4.6 |  14.2  57.6  185  10  5   7.5   4.1
  9000  13.0  55.4  155   8  4  10.4   5.7 |  14.9  58.8  185  10  5  11.1   6.1
  8750  13.8  56.8  155   9  4  11.7   6.4 |  15.7  60.3  185  10  5  11.9   6.5
  8500  14.6  58.3  155   9  4  10.3   5.7 |  16.6  61.9  185  10  5  10.3   5.6
  8250  15.4  59.7  155   8  4   9.7   5.3 |  17.3  63.1  185  10  5   9.3   5.1
  8000  16.1  61.0  155   8  4  10.3   5.6 |  18.0  64.4  185  10  5  10.4   5.7
  7750  16.9  62.4  155   8  4  10.6   5.8 |  18.8  65.8  185  10  5  10.8   5.9
  7500  17.6  63.7  155   8  4  10.3   5.6 |  19.6  67.3  185  10  5   9.9   5.4
  7250  18.4  65.1  155   8  4  10.2   5.6 |  20.3  68.5  185  10  5   9.5   5.2
  7000  19.2  66.6  150   8  4  10.2   5.6 |  21.0  69.8  185  10  5  10.3   5.7
  6750  19.9  67.8  155   8  4  10.4   5.7 |  21.8  71.2  185  10  5  10.5   5.8
  6500  20.7  69.3  155   8  4  10.6   5.8 |  22.6  72.7  185   9  5  10.1   5.5
  6250  21.5  70.7  150   8  4  10.2   5.6 |  23.3  73.9  185   9  5   9.7   5.3
  6000  22.3  72.1  150   8  4  11.6   6.4 |  24.0  75.2  185   9  5  11.4   6.3
  5750  23.4  74.1  150   8  4  19.4  10.6 |  25.1  77.2  185   9  4  16.4   9.0
  5500  25.2  77.4  150   8  4  27.8  15.3 |  26.4  79.5  180   8  4  19.1  10.5
________________________________________________________________________________

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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