Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010030
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1830 MDT Tuesday, September 30, 2014

This forecast is for Wednesday, October 1, 2014:

If the trigger temperature of 62.6 F/17.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 154 ft/min (0.8 m/s)
   Maximum height of thermals.................. 11924 ft MSL (6637 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7119 ft MSL (1832 ft AGL)
Thermal soaring outlook for Thursday 10/02..... Fair

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....................... 39539 ft MSL (34252 ft AGL)
Wave soaring outlook for Thursday 10/02........ Poor

Remarks... None

Sunrise/Sunset.................... 06:55:45 / 18:43:23 MDT
Total possible sunshine........... 11 hr 47 min 38 sec (707 min 38 sec)
Altitude of sun at 12:49:04 MDT... 46.87 degrees

Upper air data from numerical model forecast valid on 10/01/2014 at 0600 MDT

Freezing level.................. 11337 ft MSL (6050 ft AGL)
Convective condensation level... 13254 ft MSL (7967 ft AGL)
Lifted condensation level....... 12783 ft MSL (7496 ft AGL)
Lifted index.................... +1.9
K index......................... +20.8

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  -57.9 -72.2   250   35   18   2.8   1.5      M     M       M      M    M
 45000  -53.8 -64.8   245   47   24   2.3   1.2      M     M       M      M    M
 40000  -50.5 -58.9   260   57   29   2.2   1.2      M     M       M      M    M
 38000  -49.7 -57.5   260   58   30   0.7   0.4      M     M       M      M    M
 36000  -49.3 -56.7   265   57   30   0.7   0.4      M     M       M      M    M
 34000  -48.3 -54.9   265   56   29   5.1   2.8      M     M       M      M    M
 32000  -44.7 -48.5   265   52   27   5.2   2.9      M     M       M      M    M
 30000  -40.9 -41.6   260   47   24   8.6   4.7   34.7  94.5    12.4      M    M
 29000  -38.3 -36.9   260   43   22   8.6   4.7   34.2  93.6    12.1      M    M
 28000  -35.7 -32.3   255   39   20   8.6   4.7   33.8  92.9    12.0      M    M
 27000  -33.2 -27.8   250   36   18   8.0   4.4   33.4  92.1    11.8      M    M
 26000  -30.7 -23.3   250   33   17   8.0   4.4   32.6  90.8    11.3      M    M
 25000  -28.3 -18.9   245   29   15   8.1   4.4   32.0  89.6    11.0      M    M
 24000  -25.9 -14.6   245   26   13   7.0   3.9   31.5  88.7    10.7      M    M
 23000  -24.0 -11.2   250   26   13   6.3   3.4   30.1  86.2     9.7      M    M
 22000  -22.2  -8.0   260   26   14   6.3   3.5   28.8  83.9     8.7      M    M
 21000  -20.3  -4.5   265   27   14   6.6   3.6   27.7  81.9     7.8      M    M
 20000  -18.3  -0.9   265   25   13   6.7   3.7   26.5  79.8     6.9      M    M
 19500  -17.4   0.7   265   24   12   6.8   3.7   26.0  78.8     6.4      M    M
 19000  -16.4   2.5   265   23   12   6.9   3.8   25.5  78.0     6.0      M    M
 18500  -15.4   4.3   260   22   11   7.1   3.9   25.1  77.2     5.6      M    M
 18000  -14.3   6.3   265   21   11   7.2   3.9   24.6  76.3     5.2      M    M
 17500  -13.3   8.1   265   20   11   7.2   4.0   24.2  75.6     4.8      M    M
 17000  -12.2  10.0   265   20   10   7.5   4.1   23.8  74.8     4.5      M    M
 16500  -11.1  12.0   265   19   10   7.5   4.1   23.4  74.1     4.1      M    M
 16000   -9.5  14.9   270   18    9   7.2   4.0   22.8  73.0     3.6      M    M
 15500   -8.4  16.9   270   16    8   7.3   4.0   22.4  72.3     3.2      M    M
 15000   -7.4  18.7   270   15    8   6.5   3.6   21.9  71.5     2.8      M    M
 14500   -6.4  20.5   270   13    7   6.6   3.6   21.4  70.5     2.3      M    M
 14000   -5.5  22.1   265   11    6   6.6   3.6   20.9  69.6     1.8      M    M
 13500   -4.5  23.9   265    9    5   6.6   3.6   20.3  68.6     1.3      M    M
 13000   -3.5  25.7   260    7    4   6.9   3.8   19.8  67.7     0.8      M    M
 12500   -2.5  27.5   255    6    3   7.1   3.9   19.4  66.9     0.4      M    M
 12000   -1.4  29.5   245    4    2   7.6   4.2   19.0  66.2     0.0      M    M
 11500   -0.3  31.5   240    4    2   8.0   4.4   18.7  65.7    -0.3    506  2.6
 11000    0.9  33.6   235    3    2   7.4   4.1   18.4  65.2    -0.6    456  2.3
 10500    1.9  35.4   245    3    1   6.4   3.5   18.0  64.4    -1.0    410  2.1
 10250    2.5  36.5   250    2    1   9.3   5.1   17.8  64.0    -1.2    387  2.0
 10000    3.3  37.9   270    2    1  10.6   5.8   17.9  64.2    -1.1    355  1.8
  9750    4.0  39.2   300    2    1   8.4   4.6   17.8  64.1    -1.2    327  1.7
  9500    4.6  40.3   315    3    2   9.3   5.1   17.8  64.0    -1.3    300  1.5
  9250    5.3  41.5   325    4    2   8.1   4.5   17.7  63.9    -1.3    272  1.4
  9000    5.9  42.6   330    5    3   8.4   4.6   17.6  63.6    -1.4    247  1.3
  8750    6.6  43.9   325    7    4   9.6   5.3   17.5  63.5    -1.5    219  1.1
  8500    7.3  45.1   325    9    4   9.4   5.1   17.5  63.5    -1.5    190  1.0
  8250    8.0  46.4   325   10    5   9.1   5.0   17.5  63.4    -1.6    162  0.8
  8000    8.6  47.5   320   12    6   7.2   3.9   17.3  63.2    -1.7    137  0.7
  7750    9.0  48.2   315   14    7   5.2   2.9   17.1  62.7    -2.0    116  0.6
  7500    9.4  48.9   310   15    8   4.8   2.6   16.7  62.0    -2.4     99  0.5
  7250    9.7  49.5   310   16    8   5.0   2.8   16.3  61.4    -2.8     81  0.4
  7000   10.1  50.2   305   15    8   5.1   2.8   16.0  60.7    -3.2     63  0.3
  6750   10.4  50.7   305   14    7   5.8   3.2   15.6  60.1    -3.5     44  0.2
  6500   10.9  51.6   305   12    6   5.3   2.9   15.3  59.6    -3.8     24  0.1
  6250   11.2  52.2   300   10    5   3.1   1.7   14.9  58.8    -4.3      8  0.0
  6000   11.3  52.3   290    8    4   2.0   1.1   14.3  57.8    -4.9      M    M
  5750   11.4  52.5   280    7    3   4.5   2.4   13.8  56.9    -5.5      M    M
  5500   11.5  52.7   250    6    3  -6.0  -3.3   13.2  55.8    -6.2      M    M

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

           10/01/2014 at 0900 MDT          |       10/01/2014 at 1200 MDT
                                           |
K index... +20.6  LI... +1.1               | K index... +16.1  LI... -0.9
CAPE... 0.0  CIN... M                      | CAPE... +41.1  CIN... -26.4
                                           |
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 -58.1 -72.6  250  35 18   2.5   1.4 | -58.2 -72.8  245  40 21   2.5   1.4
 45000 -54.4 -65.9  255  49 25   2.4   1.3 | -54.5 -66.1  245  56 29   2.2   1.2
 40000 -50.8 -59.4  255  66 34   2.4   1.3 | -51.1 -60.0  255  63 32   2.2   1.2
 38000 -49.7 -57.5  255  66 34   1.5   0.8 | -49.8 -57.6  255  65 33   2.3   1.2
 36000 -48.8 -55.8  255  63 33   1.5   0.8 | -48.4 -55.1  255  67 34   2.3   1.3
 34000 -47.1 -52.8  255  58 30   4.7   2.6 | -46.9 -52.4  255  66 34   3.5   1.9
 32000 -44.3 -47.7  260  52 27   4.6   2.5 | -44.5 -48.1  255  56 29   3.5   1.9
 30000 -41.0 -41.8  255  44 23   7.4   4.0 | -41.6 -42.9  250  46 24   7.4   4.1
 29000 -38.8 -37.8  255  39 20   7.4   4.0 | -39.3 -38.7  250  42 21   7.5   4.1
 28000 -36.5 -33.7  250  34 17   7.4   4.0 | -37.1 -34.8  250  37 19   7.5   4.1
 27000 -34.3 -29.7  250  30 15   8.1   4.5 | -34.8 -30.6  250  33 17   8.9   4.9
 26000 -31.9 -25.4  250  28 15   8.2   4.5 | -32.1 -25.8  250  34 18   9.0   4.9
 25000 -29.4 -20.9  255  27 14   8.2   4.5 | -29.4 -20.9  250  35 18   9.0   5.0
 24000 -27.0 -16.6  255  26 13   7.8   4.3 | -26.8 -16.2  250  36 19   8.2   4.5
 23000 -24.7 -12.5  260  25 13   7.5   4.1 | -24.6 -12.3  250  34 18   7.4   4.1
 22000 -22.4  -8.3  265  23 12   7.5   4.1 | -22.4  -8.3  250  32 17   7.4   4.1
 21000 -20.2  -4.4  265  22 11   6.3   3.5 | -20.3  -4.5  250  30 15   5.8   3.2
 20000 -18.4  -1.1  260  22 11   6.2   3.4 | -18.6  -1.5  245  27 14   5.6   3.1
 19500 -17.5   0.5  260  22 11   6.2   3.4 | -17.8  -0.0  245  26 13   5.6   3.1
 19000 -16.5   2.3  260  21 11   6.2   3.4 | -16.9   1.6  245  25 13   5.6   3.1
 18500 -15.6   3.9  255  21 11   6.3   3.4 | -16.1   3.0  240  23 12   5.9   3.3
 18000 -14.7   5.5  255  20 10   6.4   3.5 | -15.1   4.8  240  22 12   6.2   3.4
 17500 -13.8   7.2  250  20 10   6.5   3.6 | -14.2   6.4  240  21 11   6.2   3.4
 17000 -12.7   9.1  250  19 10   7.6   4.2 | -13.1   8.4  240  20 10   7.7   4.2
 16500 -11.1  12.0  250  17  9   7.6   4.1 | -12.0  10.4  245  19 10   7.6   4.2
 16000 -10.0  14.0  250  16  8   7.6   4.2 | -10.3  13.5  245  17  9   8.1   4.5
 15500  -8.9  16.0  250  16  8   7.7   4.2 |  -9.1  15.6  245  16  8   8.2   4.5
 15000  -7.8  18.0  250  15  7   7.1   3.9 |  -7.9  17.8  245  15  8   7.3   4.0
 14500  -6.8  19.8  250  13  7   7.2   3.9 |  -6.8  19.8  245  13  7   7.4   4.1
 14000  -5.8  21.6  250  12  6   6.9   3.8 |  -5.8  21.6  245  12  6   7.6   4.1
 13500  -4.8  23.4  250  11  6   6.9   3.8 |  -4.7  23.5  240  11  6   7.6   4.2
 13000  -3.7  25.3  250  10  5   7.2   3.9 |  -3.6  25.5  240  10  5   7.1   3.9
 12500  -2.7  27.1  240   9  4   7.3   4.0 |  -2.6  27.3  235   8  4   6.8   3.7
 12000  -1.6  29.1  230   8  4   7.4   4.1 |  -1.6  29.1  225   7  4   7.2   4.0
 11500  -0.5  31.1  225   7  4   7.5   4.1 |  -0.5  31.1  215   7  4   7.5   4.1
 11000   0.6  33.1  220   7  3   7.3   4.0 |   0.6  33.1  205   7  4   7.3   4.0
 10500   1.7  35.1  225   5  3   6.4   3.5 |   1.6  34.9  200   6  3   6.7   3.7
 10250   2.2  36.0  225   5  2  10.0   5.5 |   2.2  36.0  195   6  3   9.0   5.0
 10000   3.1  37.6  230   4  2  10.7   5.9 |   2.9  37.2  190   5  3   9.4   5.2
  9750   3.7  38.7  250   3  1   7.7   4.2 |   3.5  38.3  180   5  2   7.2   4.0
  9500   4.3  39.7  275   2  1   8.4   4.6 |   4.0  39.2  175   4  2   8.0   4.4
  9250   4.9  40.8  300   3  1   8.3   4.6 |   4.6  40.3  165   4  2   7.0   3.9
  9000   5.5  41.9  320   3  2   7.8   4.3 |   5.1  41.2  145   3  2   7.4   4.0
  8750   6.1  43.0  325   4  2   7.2   4.0 |   5.7  42.3  130   3  2   8.5   4.6
  8500   6.6  43.9  330   5  3   7.4   4.1 |   6.2  43.2  110   4  2   8.0   4.4
  8250   7.1  44.8  335   6  3   7.2   3.9 |   6.8  44.2  100   4  2   8.9   4.9
  8000   7.6  45.7  330   7  3   6.3   3.5 |   7.5  45.5  095   5  2   9.8   5.4
  7750   8.0  46.4  325   7  3   5.4   3.0 |   8.2  46.8  095   5  2   9.6   5.3
  7500   8.4  47.1  325   6  3   5.0   2.7 |   8.9  48.0  095   5  2   9.4   5.2
  7250   8.8  47.8  320   6  3   6.4   3.5 |   9.6  49.3  095   5  2   9.9   5.5
  7000   9.4  48.9  315   5  3   7.5   4.1 |  10.4  50.7  095   5  2  10.3   5.7
  6750   9.9  49.8  310   4  2   6.6   3.6 |  11.1  52.0  095   5  2   9.4   5.2
  6500  10.3  50.5  305   3  2   6.2   3.4 |  11.8  53.2  095   5  3   9.7   5.3
  6250  10.8  51.4  290   2  1   6.1   3.4 |  12.6  54.7  095   5  2  11.3   6.2
  6000  11.2  52.2  265   2  1   6.1   3.4 |  13.5  56.3  090   5  2  11.8   6.5
  5750  11.6  52.9  235   2  1   3.7   2.1 |  14.3  57.7  090   5  2  10.5   5.8
  5500  11.7  53.1  215   3  2   3.1   1.7 |  15.2  59.4  090   4  2  14.6   8.0

           10/01/2014 at 1500 MDT          |       10/01/2014 at 1800 MDT
                                           |
K index... +27.0  LI... -0.5               | K index... +28.0  LI... -1.3
CAPE... +39.3  CIN... -19.0                | CAPE... +150.0  CIN... -5.8
                                           |
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 -58.1 -72.6  250  36 19   2.4   1.3 | -57.3 -71.1  250  35 18   2.0   1.1
 45000 -54.3 -65.7  250  51 26   2.3   1.2 | -54.3 -65.7  260  55 28   1.2   0.7
 40000 -50.9 -59.6  255  63 32   2.3   1.2 | -52.4 -62.3  250  61 31   1.2   0.7
 38000 -50.1 -58.2  250  66 34   0.8   0.4 | -51.4 -60.5  250  61 32   1.9   1.0
 36000 -49.6 -57.3  250  69 35   0.8   0.4 | -50.3 -58.5  250  60 31   1.9   1.0
 34000 -48.7 -55.7  250  67 34   4.5   2.4 | -48.7 -55.7  245  58 30   4.7   2.6
 32000 -45.7 -50.3  245  51 26   4.5   2.4 | -45.5 -49.9  245  52 27   4.7   2.6
 30000 -42.0 -43.6  245  41 21   9.1   5.0 | -42.0 -43.6  245  47 24   7.8   4.3
 29000 -39.3 -38.7  250  41 21   9.1   5.0 | -39.7 -39.5  245  44 23   7.8   4.3
 28000 -36.6 -33.9  250  42 22   9.1   5.0 | -37.4 -35.3  245  42 21   7.8   4.3
 27000 -33.9 -29.0  255  42 22   8.4   4.6 | -35.0 -31.0  245  40 20   8.6   4.7
 26000 -31.4 -24.5  255  41 21   8.3   4.6 | -32.4 -26.3  240  39 20   8.6   4.7
 25000 -28.9 -20.0  255  40 21   8.3   4.6 | -29.9 -21.8  240  38 20   8.6   4.7
 24000 -26.5 -15.7  255  40 20   7.9   4.3 | -27.3 -17.1  240  38 19   8.3   4.5
 23000 -24.3 -11.7  250  40 21   7.5   4.1 | -24.9 -12.8  245  35 18   8.1   4.4
 22000 -22.0  -7.6  245  41 21   7.5   4.1 | -22.6  -8.7  245  33 17   8.1   4.4
 21000 -19.9  -3.8  240  41 21   6.9   3.8 | -20.2  -4.4  250  31 16   6.8   3.7
 20000 -17.8  -0.0  235  41 21   6.9   3.8 | -18.2  -0.8  255  29 15   6.8   3.7
 19500 -16.8   1.8  230  41 21   6.9   3.8 | -17.2   1.0  255  28 14   6.8   3.7
 19000 -15.8   3.6  225  41 21   6.9   3.8 | -16.2   2.8  260  27 14   6.8   3.7
 18500 -14.8   5.4  220  42 21   7.3   4.0 | -15.2   4.6  265  26 14   6.9   3.8
 18000 -13.7   7.3  215  39 20   7.6   4.2 | -14.2   6.4  265  26 14   6.9   3.8
 17500 -12.6   9.3  210  37 19   7.6   4.2 | -13.2   8.2  265  26 14   6.9   3.8
 17000 -11.6  11.1  205  35 18   6.6   3.6 | -12.2  10.0  270  27 14   6.6   3.6
 16500 -10.6  12.9  200  32 16   6.7   3.7 | -11.2  11.8  270  27 14   6.6   3.6
 16000  -9.1  15.6  190  28 14   6.3   3.5 |  -9.7  14.5  270  27 14   7.3   4.0
 15500  -8.2  17.2  185  25 13   6.3   3.5 |  -8.7  16.3  265  26 14   7.3   4.0
 15000  -7.3  18.9  185  23 12   6.4   3.5 |  -7.6  18.3  265  26 13   7.4   4.1
 14500  -6.4  20.5  180  20 10   6.4   3.5 |  -6.5  20.3  260  25 13   7.4   4.1
 14000  -5.5  22.1  180  18  9   5.9   3.3 |  -5.4  22.3  260  24 12   7.6   4.2
 13500  -4.6  23.7  175  15  8   5.8   3.2 |  -4.3  24.3  255  23 12   7.7   4.2
 13000  -3.8  25.2  170  12  6   5.9   3.2 |  -3.2  26.2  250  21 11   7.4   4.1
 12500  -2.9  26.8  160  10  5   6.0   3.3 |  -2.2  28.0  250  19 10   7.3   4.0
 12000  -2.1  28.2  145   8  4   5.8   3.2 |  -1.1  30.0  245  17  9   7.2   3.9
 11500  -1.3  29.7  130   7  3   5.6   3.1 |  -0.1  31.8  240  14  7   7.0   3.9
 11000  -0.5  31.1  115   6  3   5.6   3.1 |   0.9  33.6  240  11  6   6.4   3.5
 10500   0.4  32.7  110   5  3   5.0   2.7 |   1.8  35.2  235   9  4   5.3   2.9
 10250   0.8  33.4  105   5  3   8.3   4.5 |   2.2  36.0  235   7  4   8.8   4.8
 10000   1.6  34.9  100   5  2  10.8   5.9 |   3.0  37.4  240   6  3   7.8   4.3
  9750   2.3  36.1  100   4  2   9.4   5.2 |   3.3  37.9  245   4  2   3.5   1.9
  9500   3.0  37.4  095   4  2   9.9   5.4 |   3.6  38.5  255   3  2   4.7   2.6
  9250   3.7  38.7  090   4  2   9.4   5.1 |   3.9  39.0  280   2  1   4.1   2.2
  9000   4.4  39.9  085   3  2   9.0   4.9 |   4.2  39.6  325   2  1   4.6   2.5
  8750   5.0  41.0  075   3  2   9.2   5.0 |   4.6  40.3  355   3  1   5.4   3.0
  8500   5.7  42.3  065   3  1   9.0   4.9 |   5.0  41.0  010   4  2   5.4   3.0
  8250   6.4  43.5  055   3  1   9.5   5.2 |   5.4  41.7  015   5  3   5.3   2.9
  8000   7.1  44.8  040   2  1   9.8   5.4 |   5.8  42.4  020   6  3   5.1   2.8
  7750   7.8  46.0  030   2  1   9.3   5.1 |   6.1  43.0  020   7  4   4.8   2.6
  7500   8.5  47.3  025   2  1   8.7   4.8 |   6.5  43.7  020   8  4   4.7   2.6
  7250   9.2  48.6  015   2  1  10.0   5.5 |   6.8  44.2  020   9  5   4.4   2.4
  7000  10.0  50.0  010   2  1  11.1   6.1 |   7.1  44.8  020  10  5   4.2   2.3
  6750  10.7  51.3  010   2  1   9.2   5.0 |   7.4  45.3  020  11  6   3.5   1.9
  6500  11.4  52.5  005   2  1   8.8   4.8 |   7.7  45.9  015  12  6   3.9   2.2
  6250  12.1  53.8  360   2  1  10.5   5.7 |   8.0  46.4  015  11  6   5.7   3.1
  6000  12.9  55.2  355   2  1  11.3   6.2 |   8.4  47.1  015  11  5   5.7   3.1
  5750  13.7  56.7  355   2  1   9.3   5.1 |   8.7  47.7  010  10  5   7.4   4.1
  5500  14.4  57.9  345   3  1  10.0   5.5 |   9.5  49.1  010   9  4  13.2   7.3
________________________________________________________________________________

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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