Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151248
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0648 MDT Wednesday, October 15, 2014

This forecast is for Wednesday, October 15, 2014:

If the trigger temperature of 83.1 F/28.4 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 273 ft/min (1.4 m/s)
   Maximum height of thermals.................. 9219 ft MSL (3934 ft AGL)

Forecast maximum temperature................... 83.0 F/28.8 C
Time of trigger temperature.................... 1445 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................. 7384 ft MSL (2098 ft AGL)
Thermal soaring outlook for Thursday 10/16..... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Becoming fair
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 16332 ft MSL (11047 ft AGL)
Wave soaring outlook for Thursday 10/16........ Poor

Remarks...

Sunrise/Sunset.................... 07:09:50 / 18:21:35 MDT
Total possible sunshine........... 11 hr 11 min 45 sec (671 min 45 sec)
Altitude of sun at 12:45:16 MDT... 41.56 degrees

Upper air data from rawinsonde observation taken on 10/15/2014 at 0600 MDT

Freezing level.................. 16003 ft MSL (10718 ft AGL)
Convective condensation level... 26896 ft MSL (21611 ft AGL)
Lifted condensation level....... 22621 ft MSL (17335 ft AGL)
Lifted index.................... +7.6
K index......................... -35.0

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  -69.8 -93.6   250   39   20   6.8   3.7   77.5 171.5    28.5      M    M
 45000  -61.0 -77.8   265   47   24   3.6   2.0   67.8 154.1    24.6      M    M
 40000  -55.6 -68.1   280   55   28   7.7   4.3   52.5 126.4    16.1      M    M
 38000  -52.6 -62.7   285   49   25   8.6   4.7   48.2 118.7    13.6      M    M
 36000  -47.4 -53.3   290   43   22   8.8   4.8   47.4 117.4    13.4      M    M
 34000  -43.7 -46.7   265   37   19   5.2   2.9   44.4 111.9    11.6      M    M
 32000  -39.5 -39.1   260   33   17   9.0   4.9   42.1 107.8    10.2      M    M
 30000  -34.0 -29.2   255   24   13   9.2   5.1   41.9 107.4    10.2      M    M
 29000  -31.2 -24.2   260   25   13   9.2   5.1   41.4 106.6    10.0      M    M
 28000  -28.5 -19.3   260   25   13   9.2   5.1   41.1 105.9     9.9      M    M
 27000  -25.0 -13.0   265   26   14   9.2   5.1   40.8 105.5     9.8      M    M
 26000  -22.3  -8.1   270   27   14   9.3   5.1   40.7 105.3     9.9      M    M
 25000  -19.6  -3.3   270   27   14   6.8   3.7   40.5 105.0     9.8      M    M
 24000  -18.0  -0.4   260   26   13   5.3   2.9   38.9 102.0     8.6      M    M
 23000  -16.4   2.5   255   25   13   5.3   2.9   37.3  99.1     7.4      M    M
 22000  -14.8   5.4   250   25   13   5.0   2.8   35.8  96.4     6.2      M    M
 21000  -12.6   9.3   275   21   11   8.4   4.6   34.9  94.9     5.5      M    M
 20000  -10.1  13.8   265   17    9   8.4   4.6   34.4  94.0     5.2      M    M
 19500   -8.9  16.0   265   15    7   8.4   4.6   34.2  93.5     5.0      M    M
 19000   -7.6  18.3   265   12    6   8.2   4.5   33.9  93.1     4.8      M    M
 18500   -6.4  20.5   275   11    6   8.2   4.5   33.7  92.6     4.6      M    M
 18000   -5.2  22.6   285   11    6   8.2   4.5   33.4  92.2     4.4      M    M
 17500   -3.9  25.0   285   12    6   8.2   4.5   33.2  91.7     4.2      M    M
 17000   -2.7  27.1   280   12    6   8.2   4.5   32.9  91.2     4.0      M    M
 16500   -1.5  29.3   280   13    7   8.2   4.5   32.6  90.7     3.8      M    M
 16000   -0.2  31.6   280   14    7   8.5   4.7   32.4  90.3     3.6      M    M
 15500    1.1  34.0   275   14    7   8.8   4.8   32.2  90.0     3.4      M    M
 15000    2.4  36.3   275   14    7   8.8   4.8   32.1  89.7     3.3      M    M
 14500    3.7  38.7   270   15    8   8.8   4.8   31.9  89.5     3.2      M    M
 14000    5.0  41.0   265   15    8   8.8   4.8   31.8  89.3     3.1      M    M
 13500    7.0  44.6   265   14    7   8.8   4.8   31.6  88.8     2.9      M    M
 13000    8.3  46.9   270   13    7   8.8   4.8   31.4  88.5     2.8      M    M
 12500    9.6  49.3   270   12    6   8.8   4.8   31.2  88.2     2.6      M    M
 12000   10.9  51.6   275   11    6   8.8   4.8   31.1  87.9     2.5      M    M
 11500   12.2  54.0   270   14    7   8.9   4.9   30.9  87.6     2.3      M    M
 11000   13.3  55.9   270   16    8   5.4   3.0   30.4  86.8     1.9      M    M
 10500   14.1  57.4   270   15    8   5.8   3.2   29.8  85.7     1.3      M    M
 10250   14.6  58.3   270   15    7   6.1   3.4   29.5  85.1     1.0      M    M
 10000   15.1  59.2   270   13    7   6.3   3.5   29.2  84.6     0.8      M    M
  9750   15.5  59.9   270   12    6   6.3   3.4   29.0  84.1     0.5      M    M
  9500   16.0  60.8   270   11    6   6.3   3.4   28.7  83.6     0.3      M    M
  9250   16.4  61.5   270   10    5   6.3   3.4   28.4  83.2    -0.0    272  1.4
  9000   16.9  62.4   270    9    5   6.3   3.5   28.2  82.7    -0.3    251  1.3
  8750   17.4  63.3   280    7    4   6.3   3.4   27.9  82.2    -0.5    230  1.2
  8500   17.8  64.0   295    6    3   6.4   3.5   27.6  81.7    -0.8    209  1.1
  8250   18.3  64.9   315    5    3   6.1   3.3   27.4  81.3    -1.1    187  1.0
  8000   18.7  65.7   335    5    3   7.2   3.9   27.1  80.8    -1.3    166  0.8
  7750   19.2  66.6   310    5    3   3.2   1.7   26.8  80.3    -1.6    145  0.7
  7500   19.1  66.4   295    6    3  -2.8  -1.5   26.0  78.9    -2.4    140  0.7
  7250   18.6  65.5   285    7    4 -10.8  -5.9   24.9  76.7    -3.7    147  0.7
  7000   17.3  63.1   275    9    5 -20.1 -11.0   22.9  73.2    -5.7    179  0.9
  6750   16.1  61.0   265    9    5  -7.1  -3.9   20.9  69.6    -7.7    210  1.1
  6500   15.8  60.4   255   10    5 -11.4  -6.3   19.9  67.8    -8.7    210  1.1
  6250   14.4  57.9   250   10    5 -11.3  -6.2   17.8  64.0   -10.9    244  1.2
  6000   14.5  58.1   240   11    6   6.6   3.6   17.1  62.8   -11.5    235  1.2
  5750   14.6  58.3   240    8    4  -8.7  -4.7   16.5  61.7   -12.2    225  1.1
  5500   12.4  54.3   240    4    2 -47.0 -25.8   13.8  56.8   -15.2    282  1.4

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

           10/15/2014 at 0900 MDT          |       10/15/2014 at 1200 MDT
                                           |
K index... -18.7  LI... +2.3               | K index... -19.5  LI... +2.4
CAPE... 0.0  CIN... -1.0                   | CAPE... 0.0  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 -69.4 -92.9  250  45 23   4.0   2.2 | -68.6 -91.5  245  45 23   3.6   2.0
 45000 -63.1 -81.6  255  51 26   4.1   2.2 | -62.9 -81.2  255  49 25   3.8   2.1
 40000 -56.7 -70.1  275  55 29   8.1   4.5 | -56.8 -70.2  265  65 34   8.6   4.7
 38000 -52.1 -61.8  270  47 24   7.8   4.3 | -51.9 -61.4  265  53 27   8.1   4.4
 36000 -47.4 -53.3  270  38 20   7.7   4.2 | -47.1 -52.8  265  42 21   8.0   4.4
 34000 -43.0 -45.4  265  36 18   7.1   3.9 | -42.7 -44.9  255  38 20   7.0   3.9
 32000 -38.8 -37.8  255  35 18   7.1   3.9 | -38.5 -37.3  250  39 20   7.0   3.9
 30000 -33.5 -28.3  255  37 19   8.1   4.5 | -33.5 -28.3  245  41 21   7.6   4.2
 29000 -31.0 -23.8  255  38 20   8.1   4.5 | -31.2 -24.2  245  41 21   7.6   4.2
 28000 -28.6 -19.5  255  40 20   8.5   4.7 | -28.9 -20.0  245  42 22   7.8   4.3
 27000 -25.9 -14.6  255  37 19   8.8   4.8 | -26.5 -15.7  245  41 21   8.2   4.5
 26000 -23.3  -9.9  255  35 18   8.8   4.8 | -24.0 -11.2  245  40 21   8.2   4.5
 25000 -20.6  -5.1  255  32 16   9.1   5.0 | -21.6  -6.9  240  40 20   8.4   4.6
 24000 -18.7  -1.7  255  30 16   5.9   3.3 | -19.5  -3.1  240  37 19   6.5   3.6
 23000 -16.9   1.6  255  28 15   6.0   3.3 | -17.6   0.3  240  34 18   6.5   3.6
 22000 -15.1   4.8  250  27 14   6.1   3.4 | -15.6   3.9  240  31 16   6.5   3.6
 21000 -12.9   8.8  250  25 13   7.8   4.3 | -13.2   8.2  240  29 15   8.4   4.6
 20000 -10.5  13.1  250  23 12   7.8   4.3 | -10.7  12.7  240  27 14   8.4   4.6
 19500  -9.3  15.3  250  22 11   7.8   4.3 |  -9.5  14.9  240  26 13   8.4   4.6
 19000  -8.1  17.4  250  21 11   8.2   4.5 |  -8.2  17.2  240  25 13   8.2   4.5
 18500  -6.9  19.6  250  20 10   8.3   4.5 |  -7.0  19.4  240  25 13   8.1   4.5
 18000  -5.7  21.7  250  19 10   8.3   4.6 |  -5.8  21.6  240  25 13   8.2   4.5
 17500  -4.4  24.1  250  19 10   8.6   4.7 |  -4.5  23.9  240  25 13   8.9   4.9
 17000  -3.1  26.4  250  18  9   8.6   4.7 |  -3.2  26.2  240  24 12   8.9   4.9
 16500  -1.8  28.8  245  17  9   9.0   4.9 |  -1.8  28.8  240  23 12   8.9   4.9
 16000  -0.4  31.3  245  17  9   9.0   4.9 |  -0.5  31.1  245  23 12   8.9   4.9
 15500   1.6  34.9  245  16  8   8.5   4.7 |   1.5  34.7  245  23 12   8.8   4.8
 15000   2.8  37.0  245  15  8   8.5   4.7 |   2.8  37.0  245  22 12   8.8   4.8
 14500   4.1  39.4  245  15  8   8.6   4.7 |   4.1  39.4  245  22 11   8.6   4.7
 14000   5.4  41.7  245  14  7   8.6   4.7 |   5.4  41.7  245  21 11   8.5   4.7
 13500   6.7  44.1  245  13  7   8.5   4.6 |   6.6  43.9  245  21 11   8.4   4.6
 13000   7.9  46.2  245  13  7   8.3   4.6 |   7.9  46.2  250  20 10   8.2   4.5
 12500   9.2  48.6  250  12  6   8.3   4.5 |   9.1  48.4  250  19 10   8.2   4.5
 12000  10.4  50.7  250  12  6   8.1   4.5 |  10.3  50.5  250  18  9   7.9   4.4
 11500  11.6  52.9  250  11  6   8.1   4.4 |  11.5  52.7  250  17  9   7.9   4.3
 11000  12.7  54.9  250  10  5   7.1   3.9 |  12.7  54.9  250  16  8   7.5   4.1
 10500  13.9  57.0  255  10  5   3.9   2.1 |  13.8  56.8  250  15  8   4.5   2.5
 10250  14.0  57.2  255  10  5   4.5   2.5 |  14.0  57.2  250  14  7   4.9   2.7
 10000  14.6  58.3  255   9  5   9.4   5.1 |  14.6  58.3  250  14  7   9.1   5.0
  9750  15.3  59.5  260   9  4   8.2   4.5 |  15.3  59.5  250  13  7   8.1   4.4
  9500  15.9  60.6  260   8  4   7.9   4.3 |  15.9  60.6  250  12  6   8.1   4.5
  9250  16.4  61.5  260   8  4   5.3   2.9 |  16.4  61.5  250  11  6   6.8   3.7
  9000  16.7  62.1  260   7  4   5.5   3.0 |  16.9  62.4  250  10  5   6.6   3.6
  8750  17.2  63.0  265   7  4   7.0   3.9 |  17.4  63.3  250  10  5   7.3   4.0
  8500  17.7  63.9  265   6  3   6.1   3.4 |  17.9  64.2  250   9  5   6.9   3.8
  8250  18.1  64.6  265   6  3   5.2   2.9 |  18.4  65.1  250   8  4   6.3   3.5
  8000  18.4  65.1  270   6  3   4.3   2.3 |  18.9  66.0  245   7  4   5.6   3.1
  7750  18.7  65.7  275   5  3   4.1   2.3 |  19.3  66.7  240   6  3   5.6   3.1
  7500  19.0  66.2  275   5  3   2.7   1.5 |  19.7  67.5  230   5  3   4.7   2.6
  7250  19.0  66.2  280   5  3   0.9   0.5 |  19.9  67.8  225   4  2   3.4   1.9
  7000  19.1  66.4  280   5  2   0.9   0.5 |  20.1  68.2  220   3  2   3.1   1.7
  6750  19.1  66.4  285   5  2   0.3   0.2 |  20.3  68.5  210   3  1   3.0   1.6
  6500  18.8  65.8  285   4  2 -10.9  -6.0 |  20.5  68.9  200   2  1   0.6   0.3
  6250  17.4  63.3  270   4  2 -20.2 -11.1 |  20.4  68.7  185   2  1  -0.7  -0.4
  6000  16.1  61.0  260   4  2 -13.7  -7.5 |  20.2  68.4  165   2  1  -1.4  -0.8
  5750  15.1  59.2  250   5  3 -18.0  -9.9 |  20.1  68.2  150   2  1   2.7   1.5
  5500  12.8  55.0  235   5  3 -42.2 -23.1 |  20.6  69.1  145   2  1  16.9   9.3

           10/15/2014 at 1500 MDT          |       10/15/2014 at 1800 MDT
                                           |
K index... -7.9  LI... +3.7                | K index... +4.9  LI... +2.7
CAPE... 0.0  CIN... -0.3                   | CAPE... 0.0  CIN... M
                                           |
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 -68.9 -92.0  250  49 25   2.7   1.5 | -68.5 -91.3  260  48 25   2.7   1.5
 45000 -64.0 -83.2  250  62 32   4.3   2.4 | -63.7 -82.7  265  69 35   4.0   2.2
 40000 -57.3 -71.1  255  80 41   8.4   4.6 | -57.4 -71.3  255  77 40   8.8   4.8
 38000 -52.5 -62.5  255  66 34   8.1   4.4 | -52.3 -62.1  255  68 35   8.5   4.7
 36000 -47.6 -53.7  250  53 27   8.1   4.4 | -47.2 -53.0  250  60 31   8.5   4.7
 34000 -43.1 -45.6  250  49 25   7.3   4.0 | -42.3 -44.1  250  58 30   7.9   4.3
 32000 -38.7 -37.7  245  50 26   7.3   4.0 | -37.5 -35.5  250  59 31   8.0   4.4
 30000 -33.6 -28.5  240  49 25   7.7   4.2 | -33.0 -27.4  245  54 28   6.2   3.4
 29000 -31.3 -24.3  240  48 25   7.7   4.2 | -31.2 -24.2  240  50 26   6.2   3.4
 28000 -29.0 -20.2  240  47 24   7.9   4.3 | -29.3 -20.7  235  47 24   6.7   3.7
 27000 -26.5 -15.7  240  46 24   8.1   4.5 | -26.9 -16.4  235  45 23   8.3   4.5
 26000 -24.1 -11.4  240  46 24   8.1   4.5 | -24.3 -11.7  235  43 22   8.3   4.6
 25000 -21.6  -6.9  240  46 23   8.2   4.5 | -21.8  -7.2  235  42 21   8.4   4.6
 24000 -19.3  -2.7  240  44 23   7.5   4.1 | -19.6  -3.3  240  40 21   7.2   3.9
 23000 -17.1   1.2  235  43 22   7.5   4.1 | -17.4   0.7  245  39 20   7.2   3.9
 22000 -14.8   5.4  235  41 21   7.5   4.1 | -15.3   4.5  245  38 20   7.1   3.9
 21000 -12.5   9.5  235  40 20   7.8   4.3 | -13.1   8.4  245  36 19   7.6   4.2
 20000 -10.2  13.6  230  38 20   7.8   4.3 | -10.8  12.6  245  34 18   7.6   4.2
 19500  -9.0  15.8  230  38 19   7.8   4.3 |  -9.7  14.5  245  33 17   7.6   4.2
 19000  -7.8  18.0  225  37 19   7.8   4.3 |  -8.5  16.7  245  32 16   8.2   4.5
 18500  -6.7  19.9  225  35 18   7.9   4.3 |  -7.3  18.9  245  33 17   8.5   4.7
 18000  -5.5  22.1  230  34 17   7.9   4.3 |  -6.0  21.2  250  34 17   8.6   4.7
 17500  -4.2  24.4  230  33 17   8.8   4.8 |  -4.8  23.4  250  35 18   7.7   4.2
 17000  -2.9  26.8  235  34 17   8.7   4.8 |  -3.6  25.5  255  36 19   7.8   4.3
 16500  -1.6  29.1  235  34 17   8.8   4.8 |  -2.5  27.5  260  37 19   7.2   4.0
 16000  -0.3  31.5  240  34 17   8.8   4.8 |  -1.5  29.3  255  36 18   7.0   3.8
 15500   1.6  34.9  240  33 17   8.1   4.4 |  -0.4  31.3  255  34 18   6.9   3.8
 15000   2.8  37.0  240  33 17   8.0   4.4 |   1.0  33.8  260  30 16   6.5   3.6
 14500   4.0  39.2  245  33 17   8.0   4.4 |   1.9  35.4  260  28 14   7.0   3.8
 14000   5.2  41.4  245  32 17   7.9   4.4 |   3.0  37.4  255  24 13   7.5   4.1
 13500   6.3  43.3  245  31 16   7.6   4.2 |   4.0  39.2  255  21 11   7.8   4.3
 13000   7.3  45.1  245  30 15   6.8   3.7 |   5.3  41.5  255  18  9   8.7   4.8
 12500   8.3  46.9  250  28 14   6.8   3.7 |   6.5  43.7  245  15  8   8.7   4.8
 12000   9.3  48.7  250  25 13   6.7   3.7 |   7.9  46.2  245  14  7  10.0   5.5
 11500  10.2  50.4  245  22 11   6.8   3.7 |   9.4  48.9  240  14  7  10.0   5.5
 11000  11.2  52.2  245  19 10   7.0   3.9 |  10.7  51.3  240  13  7   7.8   4.3
 10500  12.2  54.0  245  16  8   9.9   5.4 |  11.8  53.2  235  12  6  11.1   6.1
 10250  13.1  55.6  240  14  7  10.6   5.8 |  12.8  55.0  235  11  6  11.6   6.3
 10000  13.7  56.7  240  13  7   7.2   4.0 |  13.4  56.1  230  11  6   7.7   4.2
  9750  14.3  57.7  235  12  6   8.1   4.5 |  14.1  57.4  230  10  5   8.7   4.8
  9500  14.9  58.8  230  11  6   7.8   4.3 |  14.7  58.5  230  10  5   8.3   4.6
  9250  15.4  59.7  225  10  5   7.5   4.1 |  15.3  59.5  225   9  5   7.3   4.0
  9000  16.0  60.8  225  10  5   7.8   4.3 |  15.8  60.4  225   8  4   7.5   4.1
  8750  16.6  61.9  220   9  5   8.3   4.6 |  16.4  61.5  220   7  4   8.4   4.6
  8500  17.2  63.0  210   8  4   8.1   4.4 |  17.0  62.6  215   6  3   8.1   4.4
  8250  17.8  64.0  205   8  4   7.9   4.4 |  17.5  63.5  210   4  2   7.4   4.1
  8000  18.4  65.1  195   6  3   7.1   3.9 |  18.1  64.6  195   3  1   7.1   3.9
  7750  18.8  65.8  185   6  3   6.1   3.4 |  18.6  65.5  165   2  1   7.3   4.0
  7500  19.3  66.7  165   5  3   7.0   3.8 |  19.1  66.4  110   2  1   7.4   4.1
  7250  19.8  67.6  150   4  2   8.4   4.6 |  19.6  67.3  075   3  1   7.8   4.3
  7000  20.4  68.7  130   4  2   8.9   4.9 |  20.2  68.4  060   4  2   7.9   4.3
  6750  21.0  69.8  115   4  2   8.5   4.7 |  20.8  69.4  050   5  2   7.7   4.2
  6500  21.6  70.9  105   4  2   9.7   5.3 |  21.3  70.3  045   6  3   7.7   4.2
  6250  22.4  72.3  105   4  2  11.0   6.1 |  21.9  71.4  040   6  3   7.5   4.1
  6000  23.2  73.8  100   4  2  10.3   5.6 |  22.4  72.3  035   7  4   8.0   4.4
  5750  24.0  75.2  095   4  2  10.6   5.8 |  23.0  73.4  030   8  4   5.8   3.2
  5500  24.9  76.8  090   3  2  14.1   7.7 |  23.1  73.6  025   7  4  -1.1  -0.6
________________________________________________________________________________

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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