Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 121316
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0716 MDT Saturday, July 12, 2014

This forecast is for Saturday, July 12, 2014:

If the trigger temperature of 81.5 F/27.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 176 ft/min (0.9 m/s)
   Maximum height of thermals.................. 10305 ft MSL (5020 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7814 ft MSL (2529 ft AGL)
Thermal soaring outlook for Sunday 07/13....... Fair

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....................... 18348 ft MSL (13063 ft AGL)
Wave soaring outlook for Sunday 07/13.......... Poor

Remarks...

Sunrise/Sunset.................... 05:41:55 / 20:28:26 MDT
Total possible sunshine........... 14 hr 46 min 31 sec (886 min 31 sec)
Altitude of sun at 13:05:07 MDT... 72.10 degrees

Upper air data from rawinsonde observation taken on 07/12/2014 at 0600 MDT

Freezing level.................. 16752 ft MSL (11467 ft AGL)
Convective condensation level... 13533 ft MSL (8248 ft AGL)
Lifted condensation level....... 12612 ft MSL (7326 ft AGL)
Lifted index.................... -2.0
K index......................... +24.5

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  -68.0 -90.4   280   15    8   4.8   2.6   77.5 171.5    28.8      M    M
 45000  -60.7 -77.3   225   22   12  -2.5  -1.4   65.4 149.7    23.3      M    M
 40000  -51.5 -60.7   225   18    9   8.2   4.5   56.9 134.5    19.2      M    M
 38000  -46.8 -52.2   265   19   10   8.4   4.6   55.2 131.3    18.5      M    M
 36000  -42.0 -43.6   270   14    7   8.6   4.7   53.6 128.5    17.9      M    M
 34000  -36.5 -33.7   260   13    7   8.6   4.7   53.2 127.7    18.0      M    M
 32000  -30.6 -23.1   280   14    7   7.9   4.4   52.3 126.2    17.9      M    M
 30000  -25.9 -14.6   255   11    6   8.8   4.8   50.8 123.4    17.1      M    M
 29000  -23.5 -10.3   255   13    7   8.6   4.7   50.2 122.4    16.8      M    M
 28000  -21.3  -6.3   240   14    7   8.4   4.6   49.2 120.5    16.3      M    M
 27000  -19.5  -3.1   225   15    8   6.0   3.3   47.8 118.1    15.3      M    M
 26000  -17.6   0.3   230   19   10   7.6   4.2   46.5 115.8    14.5      M    M
 25000  -16.0   3.2   235   22   11   7.7   4.2   44.8 112.6    13.3      M    M
 24000  -14.0   6.8   230   23   12   6.4   3.5   43.8 110.9    12.5      M    M
 23000  -13.2   8.2   250   19   10   3.0   1.7   41.5 106.7    10.4      M    M
 22000  -10.8  12.6   245   20   10   8.0   4.4   40.7 105.3    10.0      M    M
 21000   -9.3  15.3   260   20   10   3.6   2.0   39.2 102.6     8.7      M    M
 20000   -7.8  18.0   260   22   11   9.1   5.0   37.7  99.8     7.4      M    M
 19500   -6.5  20.3   265   23   12   8.8   4.8   37.5  99.5     7.2      M    M
 19000   -5.4  22.3   260   24   12   6.4   3.5   37.2  98.9     7.0      M    M
 18500   -4.5  23.9   260   25   13   5.7   3.1   36.5  97.6     6.4      M    M
 18000   -3.7  25.3   255   26   13   5.2   2.9   35.8  96.4     5.8      M    M
 17500   -2.5  27.5   255   25   13  10.3   5.6   35.4  95.8     5.5      M    M
 17000   -1.1  30.0   260   23   12   9.7   5.3   35.4  95.8     5.5      M    M
 16500    0.4  32.7   265   22   11   8.9   4.9   35.4  95.8     5.6      M    M
 16000    2.1  35.8   270   19   10   7.9   4.3   35.0  95.0     5.2      M    M
 15500    3.3  37.9   265   17    9   8.0   4.4   34.7  94.4     4.9      M    M
 15000    4.2  39.6   260   15    8   4.4   2.4   34.0  93.3     4.3      M    M
 14500    4.8  40.6   255   13    7   4.9   2.7   33.2  91.8     3.5      M    M
 14000    5.4  41.7   250   11    6   5.7   3.1   32.4  90.4     2.7      M    M
 13500    6.3  43.3   250   12    6   6.4   3.5   31.9  89.4     2.1      M    M
 13000    7.3  45.1   245   13    6   9.0   4.9   31.5  88.7     1.7      M    M
 12500    8.8  47.8   245   13    7   9.7   5.3   31.5  88.7     1.7      M    M
 12000   10.0  50.0   245   14    7   6.5   3.6   31.2  88.2     1.5      M    M
 11500   11.0  51.8   250   10    5   6.8   3.7   30.7  87.3     1.0      M    M
 11000   12.0  53.6   260    7    4   6.8   3.7   30.2  86.4     0.6      M    M
 10500   13.0  55.4   285    5    3   7.1   3.9   29.8  85.6     0.1      M    M
 10250   13.5  56.3   280    7    3   7.6   4.1   29.6  85.3    -0.1    367  1.9
 10000   14.1  57.4   275    8    4   7.5   4.1   29.4  85.0    -0.3    344  1.7
  9750   14.6  58.3   270   10    5   7.5   4.1   29.2  84.6    -0.5    320  1.6
  9500   15.1  59.2   270   12    6   7.4   4.1   29.1  84.3    -0.7    297  1.5
  9250   15.7  60.3   265   13    7   7.8   4.3   28.9  84.0    -0.8    273  1.4
  9000   16.2  61.2   265   15    8   6.1   3.3   28.7  83.7    -1.0    250  1.3
  8750   16.5  61.7   270   13    7   4.4   2.4   28.3  83.0    -1.5    233  1.2
  8500   16.8  62.2   275   12    6   4.8   2.6   27.9  82.3    -1.9    216  1.1
  8250   17.2  63.0   280   10    5   4.7   2.6   27.6  81.6    -2.3    199  1.0
  8000   17.5  63.5   290    9    5   4.7   2.6   27.2  80.9    -2.7    182  0.9
  7750   17.8  64.0   285    7    3   5.1   2.8   26.8  80.2    -3.1    165  0.8
  7500   18.1  64.6   270    4    2   3.5   1.9   26.4  79.5    -3.5    148  0.8
  7250   18.2  64.8   240    3    1   1.2   0.7   25.8  78.5    -4.2    138  0.7
  7000   18.2  64.8   185    3    2   1.0   0.6   25.2  77.3    -4.9    131  0.7
  6750   18.2  64.8   185    3    2   1.4   0.8   24.5  76.1    -5.7    124  0.6
  6500   18.1  64.6   190    4    2  -1.9  -1.0   23.8  74.8    -6.5    118  0.6
  6250   17.7  63.9   190    4    2  -5.9  -3.2   22.7  72.9    -7.7    124  0.6
  6000   17.3  63.1   190    5    3  -1.0  -0.6   21.7  71.0    -8.8    130  0.7
  5750   17.4  63.3   190    3    2   4.5   2.5   21.1  70.0    -9.5    118  0.6
  5500   17.5  63.5   190    2    1  -2.2  -1.2   20.6  69.0   -10.1    106  0.5

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

           07/12/2014 at 0900 MDT          |       07/12/2014 at 1200 MDT
                                           |
K index... +28.0  LI... -4.3               | K index... +24.0  LI... -4.4
CAPE... +508.3  CIN... -153.4              | CAPE... +804.1  CIN... -41.4
                                           |
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 -66.9 -88.4  240  20 10   1.6   0.9 | -67.1 -88.8  245  22 11   1.6   0.9
 45000 -61.2 -78.2  240  25 13   7.3   4.0 | -61.4 -78.5  250  23 12   7.4   4.1
 40000 -50.0 -58.0  245  20 10   7.8   4.3 | -49.6 -57.3  255  16  8   7.9   4.3
 38000 -45.3 -49.5  260  17  9   7.8   4.3 | -44.9 -48.8  265  16  8   7.9   4.3
 36000 -40.6 -41.1  280  16  8   8.2   4.5 | -40.1 -40.2  275  16  8   8.4   4.6
 34000 -34.8 -30.6  280  16  8   8.5   4.7 | -35.1 -31.2  280  18  9   8.4   4.6
 32000 -29.7 -21.5  275  17  9   7.7   4.2 | -30.0 -22.0  290  19 10   8.1   4.5
 30000 -25.5 -13.9  270  17  9   7.1   3.9 | -25.5 -13.9  290  18  9   7.6   4.2
 29000 -23.4 -10.1  270  17  9   7.1   3.9 | -23.3  -9.9  290  18  9   7.7   4.2
 28000 -21.4  -6.5  265  18  9   5.3   2.9 | -20.6  -5.1  285  18  9   6.4   3.5
 27000 -19.8  -3.6  265  19 10   5.5   3.0 | -18.7  -1.7  285  18  9   6.4   3.5
 26000 -18.2  -0.8  260  21 11   5.6   3.1 | -16.9   1.6  285  19 10   6.5   3.6
 25000 -16.6   2.1  260  23 12   5.6   3.1 | -15.0   5.0  285  19 10   6.2   3.4
 24000 -15.0   5.0  260  23 12   5.5   3.0 | -13.2   8.2  285  19 10   6.2   3.4
 23000 -13.4   7.9  265  23 12   5.6   3.1 | -11.4  11.5  280  20 10   6.2   3.4
 22000 -11.8  10.8  265  24 12   5.8   3.2 |  -9.6  14.7  280  20 10   5.2   2.8
 21000 -10.0  14.0  270  22 11   6.0   3.3 |  -8.2  17.2  275  20 11   5.0   2.8
 20000  -8.3  17.1  270  20 10   6.0   3.3 |  -6.7  19.9  270  21 11   5.0   2.8
 19500  -7.4  18.7  270  19 10   6.1   3.4 |  -6.0  21.2  265  21 11   5.1   2.8
 19000  -6.4  20.5  270  18  9   7.3   4.0 |  -5.2  22.6  265  21 11   5.4   3.0
 18500  -5.3  22.5  270  18  9   7.2   4.0 |  -4.5  23.9  265  20 10   5.3   2.9
 18000  -4.2  24.4  270  17  9   7.2   3.9 |  -3.6  25.5  260  19 10   6.4   3.5
 17500  -3.2  26.2  270  16  8   7.2   3.9 |  -2.7  27.1  260  18  9   6.6   3.6
 17000  -1.6  29.1  270  16  8   7.6   4.2 |  -1.7  28.9  260  17  9   6.8   3.7
 16500  -0.5  31.1  270  15  8   7.8   4.3 |  -0.6  30.9  260  16  8   7.5   4.1
 16000   0.7  33.3  275  15  8   8.0   4.4 |   0.4  32.7  265  16  8   7.4   4.0
 15500   1.9  35.4  275  15  8   8.5   4.7 |   1.6  34.9  265  15  8   8.0   4.4
 15000   3.1  37.6  275  15  8   8.5   4.7 |   2.7  36.9  270  15  8   8.0   4.4
 14500   4.3  39.7  280  15  8   8.7   4.8 |   3.9  39.0  270  15  8   7.9   4.4
 14000   5.6  42.1  280  15  8   8.7   4.8 |   5.6  42.1  280  16  8   8.0   4.4
 13500   6.9  44.4  285  15  8   8.8   4.8 |   6.7  44.1  280  16  8   7.6   4.2
 13000   8.1  46.6  285  15  8   8.8   4.8 |   7.8  46.0  285  17  9   7.6   4.2
 12500   9.4  48.9  285  15  8   8.7   4.8 |   8.9  48.0  285  16  8   7.7   4.2
 12000  10.7  51.3  285  14  7   8.7   4.8 |  10.0  50.0  285  15  8   7.8   4.3
 11500  11.9  53.4  285  14  7   7.9   4.3 |  11.1  52.0  285  14  7   8.9   4.9
 11000  12.9  55.2  285  12  6   7.2   3.9 |  12.5  54.5  285  14  7   9.3   5.1
 10500  13.9  57.0  285  11  6   2.4   1.3 |  13.7  56.7  285  13  7   4.1   2.3
 10250  14.0  57.2  285  11  6   3.6   2.0 |  13.9  57.0  285  13  7   6.7   3.7
 10000  14.6  58.3  280  10  5   9.9   5.4 |  14.8  58.6  290  12  6  12.4   6.8
  9750  15.2  59.4  275   9  4   8.6   4.7 |  15.6  60.1  290  11  6  10.7   5.9
  9500  15.7  60.3  270   8  4   5.8   3.2 |  16.3  61.3  295  10  5   6.6   3.6
  9250  16.0  60.8  265   7  4   3.1   1.7 |  16.5  61.7  295   9  5   3.6   2.0
  9000  16.3  61.3  260   7  4   5.0   2.7 |  16.8  62.2  295   8  4   5.0   2.8
  8750  16.6  61.9  255   6  3   5.3   2.9 |  17.1  62.8  300   6  3   4.9   2.7
  8500  17.0  62.6  245   5  3   3.7   2.0 |  17.4  63.3  305   4  2   4.4   2.4
  8250  17.1  62.8  250   4  2   2.9   1.6 |  17.6  63.7  320   3  2   3.8   2.1
  8000  17.3  63.1  250   2  1   2.9   1.6 |  17.8  64.0  350   2  1   5.2   2.9
  7750  17.5  63.5  265   1  0   2.4   1.3 |  18.1  64.6  025   3  1   7.9   4.3
  7500  17.6  63.7  010   1  0   2.1   1.1 |  18.7  65.7  035   3  1   9.5   5.2
  7250  17.7  63.9  030   2  1   2.6   1.4 |  19.4  66.9  030   3  2   9.8   5.4
  7000  17.8  64.0  035   4  2   0.6   0.3 |  20.1  68.2  030   3  2  10.2   5.6
  6750  17.8  64.0  040   6  3   4.6   2.5 |  20.9  69.6  030   3  2  10.5   5.8
  6500  18.4  65.1  040   6  3  10.2   5.6 |  21.6  70.9  030   3  2  10.4   5.7
  6250  19.0  66.2  035   6  3   9.0   5.0 |  22.4  72.3  025   3  2   9.9   5.4
  6000  19.7  67.5  030   7  3  10.1   5.6 |  23.2  73.8  025   3  2  12.1   6.7
  5750  20.5  68.9  030   7  3  14.9   8.2 |  24.3  75.7  025   3  2  19.6  10.7
  5500  21.9  71.4  030   7  3  20.4  11.2 |  26.0  78.8  025   3  2  24.9  13.7

           07/12/2014 at 1500 MDT          |       07/12/2014 at 1800 MDT
                                           |
K index... +28.6  LI... -2.8               | K index... +29.2  LI... -3.1
CAPE... +347.3  CIN... -1.0                | CAPE... +541.4  CIN... -2.1
                                           |
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 -67.5 -89.5  260  23 12   1.4   0.8 | -67.3 -89.1  270  22 11   1.6   0.9
 45000 -61.8 -79.2  265  20 10   7.6   4.2 | -61.7 -79.1  260  20 10   7.2   4.0
 40000 -49.6 -57.3  275  13  7   8.2   4.5 | -49.9 -57.8  280  15  8   8.3   4.6
 38000 -44.7 -48.5  275  16  8   8.2   4.5 | -45.0 -49.0  285  18  9   8.3   4.6
 36000 -39.8 -39.6  280  18  9   8.1   4.4 | -40.0 -40.0  285  21 11   8.0   4.4
 34000 -34.9 -30.8  285  17  9   8.1   4.4 | -35.2 -31.4  290  20 10   8.0   4.4
 32000 -30.1 -22.2  290  17  9   8.2   4.5 | -30.4 -22.7  290  19 10   7.9   4.3
 30000 -25.7 -14.3  290  16  8   7.5   4.1 | -26.0 -14.8  290  16  8   7.4   4.1
 29000 -23.5 -10.3  290  16  8   7.6   4.2 | -23.8 -10.8  290  15  8   7.5   4.1
 28000 -20.8  -5.4  290  16  8   7.0   3.8 | -21.6  -6.9  295  15  8   6.9   3.8
 27000 -18.8  -1.8  290  17  9   7.0   3.8 | -19.1  -2.4  295  16  8   7.1   3.9
 26000 -16.7   1.9  290  17  9   7.0   3.9 | -17.0   1.4  300  16  8   7.2   3.9
 25000 -14.7   5.5  290  17  9   6.0   3.3 | -15.0   5.0  300  17  9   6.5   3.5
 24000 -13.0   8.6  290  18  9   5.9   3.2 | -13.1   8.4  300  18  9   6.4   3.5
 23000 -11.3  11.7  290  18  9   5.9   3.2 | -11.3  11.7  305  19 10   6.5   3.5
 22000  -9.6  14.7  290  18  9   5.5   3.0 |  -9.4  15.1  305  20 10   5.5   3.0
 21000  -7.9  17.8  290  18 10   5.5   3.0 |  -7.9  17.8  305  20 10   5.4   3.0
 20000  -6.3  20.7  290  19 10   5.5   3.0 |  -6.3  20.7  305  20 10   5.4   3.0
 19500  -5.5  22.1  290  19 10   5.6   3.1 |  -5.5  22.1  305  19 10   5.5   3.0
 19000  -4.7  23.5  290  19 10   5.6   3.1 |  -4.7  23.5  305  19 10   5.7   3.1
 18500  -3.9  25.0  290  19 10   5.6   3.1 |  -3.8  25.2  305  19 10   5.7   3.1
 18000  -3.0  26.6  290  19 10   6.0   3.3 |  -3.0  26.6  305  19 10   6.0   3.3
 17500  -2.1  28.2  295  19 10   6.0   3.3 |  -2.1  28.2  305  19 10   6.0   3.3
 17000  -1.3  29.7  295  19 10   6.2   3.4 |  -1.2  29.8  305  20 10   6.1   3.3
 16500  -0.3  31.5  295  19 10   6.5   3.6 |  -0.3  31.5  305  19 10   6.2   3.4
 16000   0.6  33.1  295  19 10   6.5   3.6 |   0.5  32.9  305  19 10   6.2   3.4
 15500   1.5  34.7  295  19 10   6.7   3.7 |   1.4  34.5  305  18  9   6.2   3.4
 15000   2.5  36.5  295  19 10   6.8   3.7 |   2.3  36.1  300  17  9   6.2   3.4
 14500   3.4  38.1  295  19 10   6.3   3.5 |   3.2  37.8  300  16  8   6.1   3.3
 14000   4.7  40.5  295  16  8   6.1   3.4 |   4.4  39.9  300  12  6   6.0   3.3
 13500   5.6  42.1  300  14  7   6.6   3.6 |   5.3  41.5  300   9  5   6.4   3.5
 13000   6.5  43.7  305  10  5   6.6   3.6 |   6.1  43.0  300   6  3   6.4   3.5
 12500   7.4  45.3  310   7  4   8.0   4.4 |   7.0  44.6  310   3  2   6.3   3.5
 12000   8.5  47.3  325   6  3   8.2   4.5 |   7.8  46.0  005   4  2   6.3   3.4
 11500   9.7  49.5  340   5  3   9.6   5.3 |   8.8  47.8  030   6  3   8.5   4.7
 11000  11.2  52.2  345   5  3  10.2   5.6 |  10.1  50.2  030   7  4   9.3   5.1
 10500  12.4  54.3  345   5  3   4.4   2.4 |  11.2  52.2  035   9  4   3.8   2.1
 10250  12.8  55.0  345   5  3   8.3   4.6 |  11.5  52.7  030   9  4   8.2   4.5
 10000  13.7  56.7  345   5  3  13.8   7.6 |  12.5  54.5  030   9  5  14.7   8.0
  9750  14.7  58.5  345   5  3  11.9   6.5 |  13.5  56.3  030   9  5  12.2   6.7
  9500  15.5  59.9  345   5  3   9.2   5.1 |  14.3  57.7  030  10  5   8.6   4.7
  9250  16.1  61.0  350   5  3   8.6   4.7 |  14.8  58.6  030  10  5   7.6   4.2
  9000  16.8  62.2  350   5  3  11.3   6.2 |  15.5  59.9  030  11  5  11.3   6.2
  8750  17.7  63.9  345   5  3  11.3   6.2 |  16.4  61.5  030  11  6  11.4   6.3
  8500  18.5  65.3  350   5  3  10.0   5.5 |  17.1  62.8  030  12  6   9.1   5.0
  8250  19.2  66.6  350   5  3   9.3   5.1 |  17.7  63.9  030  13  7   8.3   4.6
  8000  19.9  67.8  350   5  3  10.3   5.6 |  18.4  65.1  030  14  7   9.4   5.1
  7750  20.6  69.1  350   6  3  10.6   5.8 |  19.1  66.4  030  14  7   9.9   5.4
  7500  21.4  70.5  350   6  3   9.9   5.5 |  19.8  67.6  030  15  8   9.4   5.1
  7250  22.2  72.0  350   6  3  10.0   5.5 |  20.4  68.7  025  15  8   9.4   5.2
  7000  22.9  73.2  350   6  3   9.9   5.4 |  21.1  70.0  025  16  8   9.3   5.1
  6750  23.6  74.5  350   6  3  10.3   5.6 |  21.8  71.2  025  16  8   9.6   5.3
  6500  24.4  75.9  350   6  3  10.7   5.9 |  22.5  72.5  025  16  8  10.1   5.5
  6250  25.2  77.4  350   6  3  10.3   5.7 |  23.3  73.9  025  15  8   9.6   5.3
  6000  26.0  78.8  350   6  3  11.5   6.3 |  24.0  75.2  025  15  8  11.0   6.1
  5750  27.0  80.6  350   6  3  16.2   8.9 |  24.9  76.8  020  14  7  12.8   7.0
  5500  28.3  82.9  355   6  3  20.7  11.4 |  25.8  78.4  020  12  6  11.6   6.3
________________________________________________________________________________

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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