Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 270055
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1855 MDT Saturday, July 26, 2014

This forecast is for Sunday, July 27, 2014:

If the trigger temperature of 80.6 F/27.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 269 ft/min (1.4 m/s)
   Maximum height of thermals.................. 11482 ft MSL (6195 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ Between 20 mph and 30 mph
Height of the -3 thermal index................. 9004 ft MSL (3717 ft AGL)
Thermal soaring outlook for Monday 07/28....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 18567 ft MSL (13280 ft AGL)
Wave soaring outlook for Monday 07/28.......... Poor

Remarks...

Sunrise/Sunset.................... 05:54:00 / 20:18:13 MDT
Total possible sunshine........... 14 hr 24 min 13 sec (864 min 13 sec)
Altitude of sun at 13:05:56 MDT... 69.30 degrees

Upper air data from numerical model forecast valid on 07/27/2014 at 0600 MDT

Freezing level.................. 15979 ft MSL (10692 ft AGL)
Convective condensation level... 13388 ft MSL (8101 ft AGL)
Lifted condensation level....... 13007 ft MSL (7719 ft AGL)
Lifted index.................... -3.8
K index......................... +33.3

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  -68.0 -90.4   290   14    7   1.6   0.9      M     M       M      M    M
 45000  -62.0 -79.6   270   30   15   7.4   4.0      M     M       M      M    M
 40000  -50.9 -59.6   270   37   19   7.6   4.2      M     M       M      M    M
 38000  -46.3 -51.3   270   39   20   7.6   4.2      M     M       M      M    M
 36000  -41.7 -43.1   270   41   21   7.9   4.3      M     M       M      M    M
 34000  -36.9 -34.4   275   38   19   8.0   4.4      M     M       M      M    M
 32000  -32.1 -25.8   280   34   18   8.7   4.8      M     M       M      M    M
 30000  -27.1 -16.8   280   27   14   7.5   4.1   49.2 120.5    15.0      M    M
 29000  -24.9 -12.8   285   24   12   7.5   4.1   48.4 119.2    14.5      M    M
 28000  -22.8  -9.0   285   20   11   5.9   3.2   47.3 117.2    13.8      M    M
 27000  -21.1  -6.0   295   17    9   5.9   3.2   45.8 114.4    12.7      M    M
 26000  -19.4  -2.9   300   14    7   5.9   3.2   44.3 111.8    11.7      M    M
 25000  -17.6   0.3   310   12    6   6.5   3.6   43.0 109.5    10.7      M    M
 24000  -15.7   3.7   305   11    6   6.6   3.6   41.8 107.2     9.8      M    M
 23000  -13.8   7.2   305   11    6   6.6   3.6   40.6 105.1     8.9      M    M
 22000  -11.9  10.6   300   11    6   6.3   3.4   39.6 103.2     8.0      M    M
 21000  -10.0  14.0   285   11    6   6.3   3.4   38.2 100.8     6.9      M    M
 20000   -8.2  17.2   275   12    6   6.3   3.5   37.0  98.7     5.9      M    M
 19500   -7.3  18.9   270   12    6   6.5   3.6   36.5  97.7     5.5      M    M
 19000   -6.3  20.7   265   12    6   6.9   3.8   36.0  96.7     5.0      M    M
 18500   -5.4  22.3   255   11    6   6.9   3.8   35.5  95.8     4.5      M    M
 18000   -4.4  24.1   250   11    6   6.9   3.8   35.0  95.0     4.1      M    M
 17500   -3.4  25.9   245   10    5   7.0   3.8   34.5  94.1     3.6      M    M
 17000   -2.4  27.7   245   10    5   7.2   3.9   34.0  93.3     3.2      M    M
 16500   -1.4  29.5   240   10    5   7.5   4.1   33.6  92.5     2.8      M    M
 16000   -0.3  31.5   240    9    5   7.5   4.1   33.3  91.9     2.4      M    M
 15500    0.9  33.6   235    9    5   8.4   4.6   33.0  91.3     2.1      M    M
 15000    2.7  36.9   230   10    5   8.3   4.5   32.6  90.7     1.7      M    M
 14500    3.9  39.0   225   10    5   8.3   4.5   32.3  90.2     1.5      M    M
 14000    5.1  41.2   225    9    5   8.3   4.6   32.1  89.8     1.3      M    M
 13500    6.3  43.3   220    9    5   8.0   4.4   31.9  89.3     1.0      M    M
 13000    7.4  45.3   220    9    5   8.0   4.4   31.6  88.8     0.7      M    M
 12500    8.6  47.5   215    9    5   8.4   4.6   31.3  88.4     0.4      M    M
 12000    9.8  49.6   215    9    5   8.4   4.6   31.1  88.0     0.2      M    M
 11500   11.0  51.8   215    9    5   7.9   4.3   30.9  87.6    -0.0    464  2.4
 11000   12.2  54.0   220    9    5   8.0   4.4   30.6  87.0    -0.3    415  2.1
 10500   13.2  55.8   220    8    4   4.8   2.6   30.1  86.2    -0.8    370  1.9
 10250   13.5  56.3   225    8    4   5.6   3.1   29.7  85.5    -1.2    353  1.8
 10000   14.1  57.4   235    7    4   8.2   4.5   29.5  85.2    -1.4    329  1.7
  9750   14.6  58.3   240    7    3   6.6   3.6   29.4  84.9    -1.5    305  1.6
  9500   15.0  59.0   245    6    3   3.5   1.9   29.0  84.2    -1.9    288  1.5
  9250   15.1  59.2   245    6    3   2.4   1.3   28.5  83.2    -2.5    275  1.4
  9000   15.3  59.5   245    5    3   2.9   1.6   27.9  82.2    -3.1    263  1.3
  8750   15.5  59.9   240    4    2   2.3   1.3   27.4  81.3    -3.6    251  1.3
  8500   15.5  59.9   225    3    2   1.4   0.7   26.7  80.1    -4.3    241  1.2
  8250   15.6  60.1   195    2    1   1.4   0.8   26.1  78.9    -5.0    232  1.2
  8000   15.7  60.3   160    2    1   1.0   0.6   25.4  77.8    -5.6    222  1.1
  7750   15.7  60.3   135    3    2   1.3   0.7   24.8  76.6    -6.4    214  1.1
  7500   15.8  60.4   105    4    2   1.9   1.0   24.1  75.5    -7.0    204  1.0
  7250   15.9  60.6   085    5    3   1.7   0.9   23.5  74.4    -7.7    194  1.0
  7000   16.0  60.8   075    7    4   1.7   1.0   22.9  73.3    -8.3    183  0.9
  6750   16.1  61.0   060    7    4   1.6   0.9   22.3  72.2    -8.9    172  0.9
  6500   16.2  61.2   045    8    4   1.7   1.0   21.7  71.1    -9.5    161  0.8
  6250   16.4  61.5   030    9    5   1.2   0.7   21.1  69.9   -10.2    150  0.8
  6000   16.5  61.7   020   10    5   3.2   1.8   20.5  68.9   -10.8    138  0.7
  5750   16.9  62.4   010    9    5   8.3   4.5   20.2  68.4   -11.1    118  0.6
  5500   17.7  63.9   360    8    4  10.5   5.8   20.2  68.4   -11.1     89  0.5

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

           07/27/2014 at 0900 MDT          |       07/27/2014 at 1200 MDT
                                           |
K index... +31.5  LI... -3.3               | K index... +28.2  LI... -2.4
CAPE... +362.2  CIN... -38.9               | CAPE... +187.5  CIN... -33.9
                                           |
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 -67.7 -89.9  290  12  6   1.4   0.8 | -67.8 -90.0  260  13  7   1.4   0.8
 45000 -62.1 -79.8  275  25 13   7.0   3.9 | -62.4 -80.3  265  25 13   6.8   3.7
 40000 -51.3 -60.3  270  35 18   8.1   4.4 | -51.7 -61.1  270  33 17   8.5   4.7
 38000 -46.5 -51.7  270  37 19   8.1   4.4 | -46.6 -51.9  275  33 17   8.5   4.7
 36000 -41.6 -42.9  270  38 20   7.9   4.4 | -41.5 -42.7  280  33 17   8.1   4.4
 34000 -36.9 -34.4  270  35 18   7.9   4.3 | -36.7 -34.1  270  31 16   8.0   4.4
 32000 -32.2 -26.0  270  32 17   8.4   4.6 | -31.4 -24.5  265  29 15   8.6   4.7
 30000 -26.9 -16.4  275  25 13   7.9   4.3 | -26.8 -16.2  270  25 13   7.8   4.3
 29000 -24.6 -12.3  280  22 11   7.8   4.3 | -24.4 -11.9  275  22 12   7.8   4.3
 28000 -22.6  -8.7  280  19 10   5.8   3.2 | -22.1  -7.8  275  21 11   7.8   4.3
 27000 -20.9  -5.6  275  15  8   5.8   3.2 | -19.8  -3.6  270  19 10   7.8   4.3
 26000 -19.1  -2.4  270  12  6   5.8   3.2 | -17.5   0.5  265  18  9   7.8   4.3
 25000 -17.4   0.7  265  10  5   6.1   3.4 | -15.3   4.5  260  17  9   5.4   2.9
 24000 -15.6   3.9  270   9  5   6.2   3.4 | -13.8   7.2  260  16  8   5.1   2.8
 23000 -13.8   7.2  275   9  4   6.2   3.4 | -12.3   9.9  260  15  8   5.1   2.8
 22000 -12.0  10.4  285   9  4   6.4   3.5 | -10.8  12.6  260  14  7   5.8   3.2
 21000 -10.1  13.8  285  10  5   6.4   3.5 |  -9.1  15.6  270  13  7   5.8   3.2
 20000  -8.3  17.1  285  12  6   6.4   3.5 |  -7.4  18.7  285  12  6   5.9   3.2
 19500  -7.4  18.7  285  13  7   6.1   3.4 |  -6.6  20.1  290  12  6   6.0   3.3
 19000  -6.5  20.3  280  13  7   5.7   3.1 |  -5.7  21.7  290  13  7   6.1   3.3
 18500  -5.7  21.7  270  14  7   5.5   3.0 |  -4.8  23.4  295  14  7   6.1   3.3
 18000  -4.8  23.4  265  14  7   7.6   4.2 |  -3.9  25.0  295  15  8   6.4   3.5
 17500  -3.7  25.3  265  14  7   7.7   4.2 |  -3.0  26.6  295  15  8   6.5   3.6
 17000  -2.6  27.3  260  14  7   8.1   4.4 |  -2.1  28.2  295  15  8   7.0   3.8
 16500  -1.4  29.5  260  14  7   8.6   4.7 |  -1.0  30.2  290  15  8   7.9   4.3
 16000  -0.1  31.8  260  14  7   8.7   4.8 |   0.2  32.4  290  15  8   7.9   4.3
 15500   1.7  35.1  255  13  7   8.3   4.6 |   1.9  35.4  285  14  7   8.1   4.5
 15000   2.9  37.2  255  13  7   8.3   4.6 |   3.1  37.6  280  14  7   8.0   4.4
 14500   4.1  39.4  250  13  7   8.3   4.6 |   4.2  39.6  270  14  7   7.5   4.1
 14000   5.3  41.5  245  12  6   8.5   4.6 |   5.2  41.4  265  14  7   7.8   4.3
 13500   6.3  43.3  240  12  6   6.5   3.6 |   6.1  43.0  260  14  7   4.8   2.7
 13000   7.3  45.1  235  12  6   6.7   3.7 |   6.8  44.2  250  14  7   5.3   2.9
 12500   8.2  46.8  230  11  6   6.9   3.8 |   7.4  45.3  245  14  7   3.8   2.1
 12000   9.2  48.6  225  11  5   7.1   3.9 |   7.9  46.2  240  13  6   3.8   2.1
 11500  10.1  50.2  225   9  5   4.7   2.6 |   8.4  47.1  235  11  6   4.3   2.4
 11000  10.7  51.3  230   7  3   4.6   2.5 |   9.0  48.2  235   9  5   4.5   2.5
 10500  11.2  52.2  240   5  2   1.3   0.7 |   9.6  49.3  230   8  4   3.1   1.7
 10250  11.3  52.3  245   4  2   1.3   0.7 |   9.8  49.6  230   8  4   3.8   2.1
 10000  11.4  52.5  255   4  2   2.6   1.4 |  10.1  50.2  230   7  4   5.5   3.0
  9750  11.5  52.7  270   4  2   2.5   1.4 |  10.5  50.9  230   7  3   5.0   2.7
  9500  11.7  53.1  260   3  2   2.2   1.2 |  10.8  51.4  225   6  3   4.0   2.2
  9250  11.8  53.2  235   2  1   1.9   1.1 |  11.0  51.8  215   5  3   3.8   2.1
  9000  11.9  53.4  200   3  1   3.3   1.8 |  11.3  52.3  200   5  2   4.8   2.7
  8750  12.2  54.0  170   4  2   4.8   2.6 |  11.7  53.1  175   4  2   6.3   3.5
  8500  12.5  54.5  160   5  2   4.7   2.6 |  12.1  53.8  145   4  2   6.9   3.8
  8250  12.8  55.0  150   5  3   4.6   2.5 |  12.6  54.7  120   4  2   6.2   3.4
  8000  13.1  55.6  140   6  3   5.5   3.0 |  13.1  55.6  100   5  3   8.6   4.7
  7750  13.5  56.3  130   6  3   4.3   2.4 |  13.9  57.0  085   6  3  10.6   5.8
  7500  13.7  56.7  115   6  3   2.7   1.5 |  14.6  58.3  085   6  3   9.6   5.3
  7250  14.0  57.2  100   5  3   2.6   1.5 |  15.3  59.5  085   7  3   9.8   5.4
  7000  14.2  57.6  080   6  3   4.6   2.5 |  16.1  61.0  085   7  4  10.0   5.5
  6750  14.7  58.5  070   5  3   8.0   4.4 |  16.8  62.2  080   7  4  10.3   5.6
  6500  15.3  59.5  060   5  2   8.4   4.6 |  17.6  63.7  080   7  4  10.2   5.6
  6250  16.0  60.8  045   5  2   8.2   4.5 |  18.3  64.9  080   7  4  10.2   5.6
  6000  16.6  61.9  030   5  2   9.2   5.0 |  19.1  66.4  080   7  4  10.9   6.0
  5750  17.4  63.3  030   4  2  12.9   7.1 |  20.1  68.2  080   7  4  16.3   9.0
  5500  18.5  65.3  030   5  2  16.8   9.2 |  21.5  70.7  075   7  4  23.3  12.8

           07/27/2014 at 1500 MDT          |       07/27/2014 at 1800 MDT
                                           |
K index... +26.0  LI... -2.9               | K index... +25.4  LI... -2.4
CAPE... +379.3  CIN... -7.5                | CAPE... +318.4  CIN... -0.0
                                           |
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 -67.9 -90.2  260  18  9   2.0   1.1 | -67.6 -89.7  265  19 10   1.7   0.9
 45000 -61.9 -79.4  250  30 16   6.8   3.7 | -61.8 -79.2  255  35 18   6.9   3.8
 40000 -51.2 -60.2  255  30 16   8.2   4.5 | -51.0 -59.8  250  36 19   8.1   4.4
 38000 -46.3 -51.3  265  29 15   8.2   4.5 | -46.2 -51.2  260  33 17   8.1   4.4
 36000 -41.4 -42.5  275  29 15   8.2   4.5 | -41.3 -42.3  265  31 16   8.2   4.5
 34000 -36.5 -33.7  275  30 15   8.2   4.5 | -36.3 -33.3  275  30 16   8.2   4.5
 32000 -30.9 -23.6  270  30 16   8.4   4.6 | -30.8 -23.4  280  30 16   8.4   4.6
 30000 -26.4 -15.5  275  30 16   7.6   4.2 | -26.3 -15.3  280  29 15   7.6   4.2
 29000 -24.2 -11.6  275  30 16   7.6   4.2 | -24.1 -11.4  280  28 14   7.6   4.2
 28000 -22.0  -7.6  275  30 15   7.0   3.8 | -22.0  -7.6  285  27 14   6.6   3.6
 27000 -20.0  -4.0  275  29 15   7.0   3.8 | -20.0  -4.0  285  27 14   6.6   3.6
 26000 -17.9  -0.2  275  29 15   7.0   3.9 | -18.1  -0.6  285  27 14   6.6   3.6
 25000 -15.9   3.4  275  28 14   6.4   3.5 | -16.1   3.0  290  26 13   6.4   3.5
 24000 -14.0   6.8  275  25 13   6.4   3.5 | -14.3   6.3  290  22 12   6.4   3.5
 23000 -12.2  10.0  280  22 11   6.4   3.5 | -12.4   9.7  290  19 10   6.5   3.6
 22000 -10.4  13.3  280  19 10   5.3   2.9 | -10.5  13.1  290  16  8   6.2   3.4
 21000  -8.8  16.2  290  17  9   5.3   2.9 |  -8.7  16.3  300  12  6   6.2   3.4
 20000  -7.3  18.9  300  14  7   5.3   2.9 |  -6.9  19.6  315   9  5   6.2   3.4
 19500  -6.5  20.3  305  14  7   6.0   3.3 |  -6.0  21.2  325   8  4   6.0   3.3
 19000  -5.5  22.1  310  14  7   7.0   3.9 |  -5.1  22.8  335   8  4   5.7   3.1
 18500  -4.4  24.1  310  14  7   7.1   3.9 |  -4.3  24.3  340   9  5   5.7   3.1
 18000  -3.5  25.7  315  14  7   6.1   3.3 |  -3.4  25.9  345  10  5   5.7   3.1
 17500  -2.6  27.3  315  13  7   6.1   3.4 |  -2.6  27.3  355  11  6   5.7   3.1
 17000  -1.7  28.9  320  13  7   6.9   3.8 |  -1.7  28.9  360  11  6   6.3   3.4
 16500  -0.6  30.9  320  13  7   8.1   4.5 |  -0.7  30.7  360  12  6   7.4   4.1
 16000   0.6  33.1  320  13  7   8.2   4.5 |   0.4  32.7  360  12  6   7.5   4.1
 15500   2.2  36.0  320  13  7   7.2   3.9 |   1.9  35.4  005  11  6   6.9   3.8
 15000   3.2  37.8  315  13  7   7.1   3.9 |   2.9  37.2  005  10  5   6.9   3.8
 14500   4.2  39.6  310  12  6   6.7   3.7 |   3.8  38.8  005   9  5   6.2   3.4
 14000   5.2  41.4  305  12  6   6.9   3.8 |   4.7  40.5  360   8  4   6.4   3.5
 13500   6.0  42.8  305  12  6   4.0   2.2 |   5.5  41.9  350   7  4   5.1   2.8
 13000   6.5  43.7  295  12  6   4.4   2.4 |   6.2  43.2  330   6  3   5.2   2.9
 12500   7.0  44.6  290  11  6   3.0   1.7 |   6.9  44.4  300   6  3   5.2   2.8
 12000   7.4  45.3  275  11  6   2.9   1.6 |   7.7  45.9  280   8  4   5.2   2.9
 11500   7.9  46.2  260  10  5   5.0   2.7 |   8.4  47.1  265   9  5   5.1   2.8
 11000   8.6  47.5  250   9  5   5.3   2.9 |   9.0  48.2  255   9  5   5.2   2.8
 10500   9.3  48.7  235   8  4   3.9   2.1 |   9.7  49.5  240   9  5   3.6   2.0
 10250   9.6  49.3  230   7  4   5.2   2.8 |   9.9  49.8  235   9  5   5.1   2.8
 10000  10.0  50.0  220   7  3   7.4   4.1 |  10.3  50.5  225   8  4   7.3   4.0
  9750  10.5  50.9  210   6  3   6.8   3.8 |  10.8  51.4  205   8  4   7.1   3.9
  9500  10.9  51.6  190   6  3   5.9   3.3 |  11.2  52.2  195   8  4   6.9   3.8
  9250  11.3  52.3  170   6  3   5.8   3.2 |  11.7  53.1  185   8  4   6.9   3.8
  9000  11.7  53.1  155   7  4   7.7   4.2 |  12.2  54.0  175   8  4  10.1   5.5
  8750  12.2  54.0  140   8  4   9.1   5.0 |  13.0  55.4  165   9  5  10.8   5.9
  8500  12.9  55.2  135   8  4   9.1   5.0 |  13.7  56.7  165   9  5   9.0   5.0
  8250  13.5  56.3  135   8  4   8.5   4.7 |  14.4  57.9  165   9  5   8.9   4.9
  8000  14.2  57.6  130   8  4  11.0   6.0 |  15.1  59.2  165   9  5  10.5   5.8
  7750  15.1  59.2  130   8  4  11.7   6.4 |  15.9  60.6  165   9  5  10.8   5.9
  7500  15.9  60.6  130   8  4   9.5   5.2 |  16.6  61.9  165   9  5   9.2   5.1
  7250  16.6  61.9  130   8  4  10.3   5.7 |  17.3  63.1  165   9  5   9.7   5.3
  7000  17.3  63.1  130   8  4   9.2   5.1 |  18.0  64.4  160   9  5   9.4   5.2
  6750  18.0  64.4  125   8  4   9.6   5.3 |  18.8  65.8  160   9  5  10.0   5.5
  6500  18.8  65.8  125   8  4  10.8   5.9 |  19.5  67.1  160   9  5  10.6   5.8
  6250  19.6  67.3  125   8  4  10.4   5.7 |  20.3  68.5  160   9  4  10.3   5.7
  6000  20.4  68.7  125   8  4  11.7   6.4 |  21.1  70.0  160   9  4  10.9   6.0
  5750  21.4  70.5  125   7  4  16.9   9.2 |  21.9  71.4  160   8  4  13.4   7.3
  5500  22.9  73.2  120   7  4  22.5  12.4 |  23.0  73.4  155   8  4  15.7   8.6
________________________________________________________________________________

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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