Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 131241
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0640 MDT Saturday, September 13, 2014

This forecast is for Saturday, September 13, 2014:

If the trigger temperature of 74.5 F/23.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 386 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10515 ft MSL (5230 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1415 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................. 7740 ft MSL (2455 ft AGL)
Thermal soaring outlook for Sunday 09/14....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 16108 ft MSL (10823 ft AGL)
Wave soaring outlook for Sunday 09/14.......... Fair

Remarks...

Sunrise/Sunset.................... 06:38:41 / 19:12:50 MDT
Total possible sunshine........... 12 hr 34 min 9 sec (754 min 9 sec)
Altitude of sun at 12:55:16 MDT... 53.84 degrees

Upper air data from rawinsonde observation taken on 09/13/2014 at 0600 MDT

Freezing level.................. 14866 ft MSL (9581 ft AGL)
Convective condensation level... 22203 ft MSL (16918 ft AGL)
Lifted condensation level....... 18476 ft MSL (13190 ft AGL)
Lifted index.................... +6.4
K index......................... -26.3

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  -65.7 -86.3   280   48   25   4.6   2.5   85.6 186.1    35.1      M    M
 45000  -60.1 -76.2   270   61   32   4.6   2.5   69.2 156.5    27.5      M    M
 40000  -53.9 -65.0   255   65   33   6.2   3.4   56.2 133.2    20.8      M    M
 38000  -51.8 -61.2   265   62   32   1.9   1.1   50.6 123.0    17.5      M    M
 36000  -48.1 -54.6   270   61   31   7.7   4.2   47.6 117.7    15.9      M    M
 34000  -43.1 -45.6   275   60   31   8.1   4.5   46.2 115.2    15.3      M    M
 32000  -38.3 -36.9   275   58   30   7.9   4.3   45.0 113.0    14.7      M    M
 30000  -32.7 -26.9   280   56   29   9.2   5.0   43.7 110.7    14.2      M    M
 29000  -30.5 -22.9   280   55   28   6.2   3.4   42.7 108.8    13.6      M    M
 28000  -28.6 -19.5   280   50   26   6.0   3.3   41.3 106.3    12.7      M    M
 27000  -27.3 -17.1   280   46   24   7.6   4.2   39.2 102.6    11.2      M    M
 26000  -24.8 -12.6   275   42   22   8.2   4.5   38.6 101.5    10.9      M    M
 25000  -22.6  -8.7   275   38   19   6.8   3.8   37.8 100.1    10.3      M    M
 24000  -20.2  -4.4   270   34   18   8.3   4.6   37.1  98.8     9.9      M    M
 23000  -17.7   0.1   265   33   17   8.4   4.6   36.6  97.9     9.6      M    M
 22000  -15.6   3.9   275   30   16   6.0   3.3   35.6  96.0     8.8      M    M
 21000  -13.8   7.2   285   28   14   6.0   3.3   34.2  93.6     7.8      M    M
 20000  -13.2   8.2   295   27   14   4.7   2.6   31.6  88.9     5.6      M    M
 19500  -12.2  10.0   290   27   14   6.7   3.7   31.1  88.0     5.2      M    M
 19000  -11.1  12.0   290   27   14   7.5   4.1   30.6  87.1     4.8      M    M
 18500  -10.0  14.0   290   26   13   8.2   4.5   30.3  86.5     4.5      M    M
 18000   -8.7  16.3   290   24   13   8.8   4.8   30.1  86.1     4.4      M    M
 17500   -7.3  18.9   290   23   12   8.8   4.9   29.9  85.9     4.2      M    M
 17000   -6.0  21.2   295   22   11   8.8   4.9   29.8  85.6     4.1      M    M
 16500   -4.7  23.5   295   21   11   8.8   4.9   29.7  85.4     4.1      M    M
 16000   -3.4  25.9   295   19   10   8.8   4.9   29.6  85.3     4.0      M    M
 15500   -2.0  28.4   290   17    9   8.8   4.9   29.4  84.9     3.9      M    M
 15000   -0.0  32.0   285   13    7   8.8   4.9   29.1  84.4     3.7      M    M
 14500    1.3  34.3   275   11    6   8.9   4.9   29.0  84.2     3.6      M    M
 14000    2.6  36.7   265   10    5   9.2   5.0   28.8  83.9     3.5      M    M
 13500    3.8  38.8   260   12    6   5.5   3.0   28.5  83.2     3.1      M    M
 13000    4.6  40.3   260   14    7   5.7   3.1   27.8  82.0     2.6      M    M
 12500    5.5  41.9   275   16    8   7.4   4.0   27.2  80.9     2.0      M    M
 12000    6.8  44.2   280   18    9   8.3   4.5   27.0  80.5     1.8      M    M
 11500    8.0  46.4   290   19   10   8.6   4.7   26.7  80.1     1.6      M    M
 11000    9.0  48.2   295   20   10   2.9   1.6   26.3  79.3     1.2      M    M
 10500    9.2  48.6   290   19   10   2.2   1.2   24.9  76.9    -0.2    384  1.9
 10250    9.4  48.9   290   19   10   5.9   3.3   24.4  76.0    -0.7    369  1.9
 10000   10.0  50.0   290   18    9   8.1   4.4   24.3  75.7    -0.8    345  1.8
  9750   10.5  50.9   290   17    9   7.5   4.1   24.1  75.4    -1.0    320  1.6
  9500   11.1  52.0   285   16    8   7.7   4.2   23.9  75.1    -1.2    296  1.5
  9250   11.7  53.1   285   15    8   7.7   4.2   23.8  74.8    -1.3    272  1.4
  9000   12.2  54.0   285   14    7   7.7   4.2   23.6  74.5    -1.5    248  1.3
  8750   12.8  55.0   290   13    6   7.7   4.2   23.5  74.2    -1.7    224  1.1
  8500   13.3  55.9   295   11    6   7.6   4.2   23.3  74.6    -1.9    200  1.0
  8250   13.9  57.0   300   10    5   8.2   4.5   23.2  73.7    -2.1    176  0.9
  8000   14.4  57.9   305    9    5   6.3   3.4   23.0  73.4    -2.2    152  0.8
  7750   14.5  58.1   305    8    4  -7.1  -3.9   22.3  72.2    -3.0    144  0.7
  7500   13.5  56.3   300    6    3  -8.9  -4.9   20.7  69.3    -4.7    165  0.8
  7250   13.2  55.8   295    5    3  -1.3  -0.7   19.7  67.4    -5.7    167  0.8
  7000   13.0  55.4   290    4    2  -3.9  -2.1   18.8  65.8    -6.7    167  0.8
  6750   12.7  54.9   255    5    2   1.5   0.8   17.8  64.1    -7.7    166  0.8
  6500   12.5  54.5   230    7    3 -17.2  -9.4   16.9  62.4    -8.7    166  0.8
  6250    9.8  49.6   220    9    5 -41.6 -22.8   13.6  56.5   -12.1    238  1.2
  6000    7.1  44.8   215   12    6 -26.6 -14.6   10.1  50.2   -15.6    314  1.6
  5750    5.8  42.4   215    8    4 -12.0  -6.6    8.1  46.5   -17.7    346  1.8
  5500    4.5  40.1   215    4    2 -27.9 -15.3    6.1  42.9   -19.8    377  1.9

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

           09/13/2014 at 0900 MDT          |       09/13/2014 at 1200 MDT
                                           |
K index... -12.6  LI... +4.3               | K index... -16.2  LI... +4.0
CAPE... 0.0  CIN... -4.5                   | CAPE... 0.0  CIN... -0.8
                                           |
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 -64.3 -83.7  275  42 22   3.7   2.0 | -64.3 -83.7  275  45 23   3.6   2.0
 45000 -59.3 -74.7  280  58 30   1.9   1.1 | -59.3 -74.7  280  57 29   2.4   1.3
 40000 -56.0 -68.8  270  59 31   6.6   3.6 | -55.2 -67.4  270  59 30   5.9   3.3
 38000 -52.1 -61.8  270  56 29   6.5   3.5 | -51.8 -61.2  270  56 29   5.7   3.2
 36000 -48.2 -54.8  270  52 27   6.5   3.6 | -48.3 -54.9  265  53 27   5.8   3.2
 34000 -43.6 -46.5  270  49 25   8.2   4.5 | -43.9 -47.0  265  50 26   8.0   4.4
 32000 -38.7 -37.7  270  47 24   8.2   4.5 | -39.1 -38.4  270  46 24   8.0   4.4
 30000 -34.0 -29.2  275  43 22   7.7   4.2 | -34.5 -30.1  270  41 21   7.7   4.2
 29000 -31.1 -24.0  280  41 21   7.7   4.2 | -31.6 -24.9  275  38 19   7.7   4.2
 28000 -28.8 -19.8  285  39 20   7.7   4.2 | -29.3 -20.7  275  35 18   7.8   4.3
 27000 -26.5 -15.7  285  37 19   7.6   4.2 | -26.9 -16.4  275  34 18   8.0   4.4
 26000 -24.2 -11.6  285  36 18   7.6   4.2 | -24.5 -12.1  280  34 17   8.0   4.4
 25000 -21.9  -7.4  285  34 17   7.7   4.2 | -22.1  -7.8  280  33 17   8.2   4.5
 24000 -19.9  -3.8  285  32 17   6.3   3.5 | -20.0  -4.0  280  32 17   6.6   3.6
 23000 -18.0  -0.4  280  31 16   6.3   3.5 | -18.0  -0.4  285  32 16   6.6   3.6
 22000 -16.1   3.0  280  29 15   6.4   3.5 | -16.0   3.2  290  31 16   6.6   3.6
 21000 -14.3   6.3  280  28 14   6.0   3.3 | -14.1   6.6  290  30 16   6.3   3.4
 20000 -12.5   9.5  280  27 14   6.0   3.3 | -12.3   9.9  290  30 15   6.3   3.4
 19500 -11.7  10.9  280  26 13   6.0   3.3 | -11.3  11.7  290  30 15   6.3   3.4
 19000 -10.7  12.7  280  25 13   6.9   3.8 | -10.4  13.3  290  30 15   6.5   3.6
 18500  -9.6  14.7  280  25 13   7.3   4.0 |  -9.4  15.1  290  28 15   6.6   3.6
 18000  -8.5  16.7  280  24 12   7.4   4.0 |  -8.4  16.9  290  27 14   6.5   3.6
 17500  -7.4  18.7  280  23 12   7.9   4.3 |  -7.5  18.5  290  25 13   5.9   3.3
 17000  -6.2  20.8  280  21 11   7.8   4.3 |  -6.6  20.1  285  22 12   5.9   3.3
 16500  -5.1  22.8  280  20 10   7.5   4.1 |  -5.7  21.7  285  20 10   6.8   3.7
 16000  -3.9  25.0  280  18  9   7.4   4.1 |  -4.7  23.5  290  17  9   7.0   3.8
 15500  -2.8  27.0  280  16  8   7.6   4.1 |  -3.6  25.5  290  14  7   7.6   4.2
 15000  -1.7  28.9  280  15  8   7.8   4.3 |  -2.4  27.7  295  13  6   8.6   4.7
 14500   0.1  32.2  290  13  7   7.9   4.3 |  -0.4  31.3  305  12  6   8.7   4.8
 14000   1.2  34.2  295  13  7   7.9   4.3 |   0.9  33.6  310  12  6   8.8   4.8
 13500   2.4  36.3  300  13  7   7.8   4.3 |   2.2  36.0  310  13  7   9.1   5.0
 13000   3.5  38.3  305  13  7   7.7   4.2 |   3.6  38.5  315  14  7   9.3   5.1
 12500   4.7  40.5  310  14  7   7.9   4.3 |   5.0  41.0  315  16  8   9.1   5.0
 12000   5.9  42.6  310  15  8   8.3   4.6 |   6.3  43.3  315  18  9   8.7   4.7
 11500   7.1  44.8  310  17  9   8.1   4.5 |   7.6  45.7  315  20 10   8.4   4.6
 11000   8.2  46.8  310  19 10   7.1   3.9 |   8.8  47.8  315  21 11   7.5   4.1
 10500   9.2  48.6  305  22 11   5.3   2.9 |   9.9  49.8  310  23 12   5.4   3.0
 10250   9.5  49.1  305  22 11   4.3   2.4 |  10.2  50.4  310  23 12   4.7   2.6
 10000  10.0  50.0  305  23 12   8.1   4.5 |  10.7  51.3  310  23 12   8.0   4.4
  9750  10.6  51.1  305  23 12   9.6   5.2 |  11.3  52.3  310  23 12   8.4   4.6
  9500  11.2  52.2  300  24 12   8.2   4.5 |  11.8  53.2  305  23 12   7.4   4.0
  9250  11.7  53.1  300  24 12   5.3   2.9 |  12.2  54.0  305  22 12   5.5   3.0
  9000  12.1  53.8  300  24 12   6.4   3.5 |  12.6  54.7  305  21 11   7.0   3.9
  8750  12.6  54.7  300  23 12   8.7   4.8 |  13.2  55.8  305  20 10   8.7   4.8
  8500  13.2  55.8  300  22 11   6.6   3.6 |  13.7  56.7  300  19 10   7.7   4.2
  8250  13.6  56.5  300  21 11   4.7   2.6 |  14.3  57.7  300  17  9   7.2   4.0
  8000  13.9  57.0  295  19 10   4.4   2.4 |  14.8  58.6  300  15  8   6.7   3.7
  7750  14.2  57.6  295  17  9   4.7   2.6 |  15.2  59.4  300  14  7   5.6   3.1
  7500  14.5  58.1  295  16  8   1.1   0.6 |  15.5  59.9  300  12  6   3.0   1.6
  7250  14.4  57.9  295  13  7  -2.0  -1.1 |  15.6  60.1  300   9  5   1.4   0.7
  7000  14.3  57.7  295  11  6  -0.8  -0.4 |  15.7  60.3  300   7  3   1.3   0.7
  6750  14.1  57.4  295   9  5  -3.9  -2.1 |  15.8  60.4  295   4  2   1.6   0.9
  6500  13.6  56.5  290   7  4  -8.7  -4.8 |  15.9  60.6  290   2  1   3.5   1.9
  6250  12.8  55.0  275   5  3 -10.2  -5.6 |  16.2  61.2  250   1  0   4.9   2.7
  6000  12.1  53.8  255   4  2  -8.4  -4.6 |  16.4  61.5  165   1  1   2.3   1.3
  5750  11.5  52.7  215   4  2  -8.0  -4.4 |  16.5  61.7  145   3  2   7.7   4.3
  5500  10.6  51.1  200   3  2 -11.3  -6.2 |  17.7  63.9  140   3  1  23.7  13.0

           09/13/2014 at 1500 MDT          |       09/13/2014 at 1800 MDT
                                           |
K index... +0.9  LI... +1.7                | K index... +14.2  LI... +0.4
CAPE... 0.0  CIN... M                      | CAPE... 0.0  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 -64.6 -84.3  270  49 25   4.5   2.4 | -65.2 -85.4  270  53 27   3.9   2.1
 45000 -58.5 -73.3  275  62 32   2.6   1.4 | -59.1 -74.4  275  66 34   4.1   2.2
 40000 -54.3 -65.7  270  57 29   4.8   2.6 | -53.0 -63.4  280  58 30   3.7   2.1
 38000 -51.5 -60.7  270  56 29   4.7   2.6 | -50.8 -59.4  275  55 28   3.7   2.0
 36000 -48.6 -55.5  270  55 28   4.8   2.6 | -48.5 -55.3  275  52 27   3.8   2.1
 34000 -44.3 -47.7  270  52 27   8.2   4.5 | -44.4 -47.9  275  50 26   8.5   4.6
 32000 -39.4 -38.9  270  49 25   8.3   4.5 | -39.3 -38.7  275  48 25   8.5   4.7
 30000 -34.7 -30.5  270  43 22   7.5   4.1 | -34.2 -29.6  275  43 22   7.2   3.9
 29000 -31.9 -25.4  265  38 20   7.5   4.1 | -32.0 -25.6  280  40 21   7.2   3.9
 28000 -29.6 -21.3  265  35 18   7.6   4.2 | -29.8 -21.6  280  37 19   7.4   4.1
 27000 -27.3 -17.1  270  33 17   7.8   4.3 | -27.5 -17.5  280  35 18   8.0   4.4
 26000 -25.0 -13.0  270  32 17   7.8   4.3 | -25.1 -13.2  275  33 17   8.0   4.4
 25000 -22.7  -8.9  275  32 16   7.9   4.3 | -22.7  -8.9  275  30 16   8.1   4.4
 24000 -20.6  -5.1  280  31 16   6.7   3.7 | -20.6  -5.1  275  30 15   6.7   3.7
 23000 -18.6  -1.5  280  30 15   6.7   3.7 | -18.5  -1.3  280  31 16   6.7   3.7
 22000 -16.6   2.1  285  29 15   6.7   3.6 | -16.5   2.3  285  32 16   6.8   3.7
 21000 -14.5   5.9  285  29 15   7.2   4.0 | -14.6   5.7  285  33 17   6.2   3.4
 20000 -12.3   9.9  290  30 15   7.2   4.0 | -12.8   9.0  285  34 17   6.2   3.4
 19500 -11.3  11.7  290  30 15   7.2   4.0 | -11.9  10.6  285  34 18   6.2   3.4
 19000 -10.2  13.6  290  30 16   7.3   4.0 | -10.9  12.4  285  35 18   6.6   3.6
 18500  -9.1  15.6  290  30 16   7.3   4.0 | -10.0  14.0  285  34 18   6.7   3.7
 18000  -8.0  17.6  290  31 16   7.3   4.0 |  -9.0  15.8  285  34 18   6.9   3.8
 17500  -6.9  19.6  290  31 16   7.3   4.0 |  -7.9  17.8  280  33 17   8.2   4.5
 17000  -5.8  21.6  290  31 16   7.3   4.0 |  -6.7  19.9  280  33 17   8.1   4.5
 16500  -4.8  23.4  290  32 16   7.0   3.9 |  -5.5  22.1  275  32 16   8.8   4.8
 16000  -3.7  25.3  290  32 17   7.0   3.8 |  -4.2  24.4  275  30 15   8.9   4.9
 15500  -2.7  27.1  290  33 17   7.1   3.9 |  -2.9  26.8  270  28 15   8.9   4.9
 15000  -1.6  29.1  285  33 17   7.2   4.0 |  -1.0  30.2  270  26 13   8.9   4.9
 14500  -0.0  32.0  285  32 17   7.6   4.2 |   0.3  32.5  270  24 12   8.8   4.8
 14000   1.1  34.0  285  31 16   7.8   4.3 |   1.6  34.9  275  22 11   8.8   4.8
 13500   2.2  36.0  285  29 15   8.0   4.4 |   3.0  37.4  275  21 11   8.7   4.7
 13000   3.4  38.1  285  27 14   8.3   4.6 |   4.2  39.6  275  20 10   8.5   4.6
 12500   4.6  40.3  285  25 13   8.5   4.7 |   5.5  41.9  280  18  9   8.4   4.6
 12000   5.9  42.6  290  23 12   8.8   4.8 |   6.7  44.1  280  17  9   8.1   4.4
 11500   7.2  45.0  290  21 11   8.7   4.8 |   7.9  46.2  285  15  8   8.0   4.4
 11000   8.5  47.3  295  20 10   8.3   4.6 |   9.1  48.4  285  13  7   7.7   4.2
 10500   9.8  49.6  295  18  9   5.2   2.8 |  10.3  50.5  290  12  6   4.0   2.2
 10250  10.0  50.0  295  18  9   6.1   3.3 |  10.4  50.7  290  11  6   4.5   2.4
 10000  10.8  51.4  300  17  9  11.2   6.2 |  11.1  52.0  290  10  5   9.9   5.4
  9750  11.5  52.7  300  15  8  10.6   5.8 |  11.7  53.1  290   8  4   8.9   4.9
  9500  12.3  54.1  305  14  7   9.2   5.1 |  12.4  54.3  295   7  3   8.1   4.4
  9250  12.9  55.2  305  13  7   6.8   3.7 |  12.9  55.2  300   5  3   5.9   3.2
  9000  13.4  56.1  310  12  6   7.7   4.2 |  13.3  55.9  300   3  2   6.8   3.7
  8750  14.0  57.2  315  11  6   9.1   5.0 |  13.9  57.0  310   2  1   7.8   4.3
  8500  14.7  58.5  320  10  5   7.2   3.9 |  14.4  57.9  050   1  0   7.3   4.0
  8250  15.1  59.2  325   8  4   5.4   3.0 |  15.0  59.0  090   1  1   7.0   3.9
  8000  15.5  59.9  335   6  3   5.6   3.1 |  15.5  59.9  100   2  1   7.1   3.9
  7750  15.9  60.6  345   5  3   5.4   3.0 |  16.0  60.8  095   2  1   7.1   3.9
  7500  16.2  61.2  005   4  2   6.3   3.4 |  16.5  61.7  090   3  1   8.1   4.5
  7250  16.7  62.1  015   3  2   7.0   3.8 |  17.1  62.8  085   2  1   9.0   5.0
  7000  17.1  62.8  030   3  1   6.9   3.8 |  17.7  63.9  080   2  1   8.9   4.9
  6750  17.6  63.7  045   3  1   8.4   4.6 |  18.3  64.9  075   2  1   9.4   5.1
  6500  18.2  64.8  050   3  1  10.2   5.6 |  19.0  66.2  070   2  1   9.9   5.4
  6250  19.0  66.2  045   2  1  11.0   6.1 |  19.7  67.5  065   2  1  10.0   5.5
  6000  19.8  67.6  045   2  1   9.0   4.9 |  20.5  68.9  060   2  1  10.1   5.6
  5750  20.4  68.7  045   2  1  11.4   6.2 |  21.2  70.2  055   2  1  10.1   5.5
  5500  21.6  70.9  045   2  1  21.0  11.5 |  21.9  71.4  055   2  1   9.6   5.3
________________________________________________________________________________

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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