Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250121
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1921 MDT Sunday, August 24, 2014

This forecast is for Monday, August 25, 2014:

If the trigger temperature of 76.4 F/24.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 867 ft/min (4.4 m/s)
   Maximum height of thermals.................. 13176 ft MSL (7889 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1130 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................. 8754 ft MSL (3466 ft AGL)
Thermal soaring outlook for Tuesday 08/26...... Poor

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)................ Weak PVA
Potential height of wave....................... 25246 ft MSL (19959 ft AGL)
Wave soaring outlook for Tuesday 08/26......... Poor

Remarks... None

Sunrise/Sunset.................... 06:20:58 / 19:42:41 MDT
Total possible sunshine........... 13 hr 21 min 44 sec (801 min 44 sec)
Altitude of sun at 13:01:25 MDT... 60.81 degrees

Upper air data from numerical model forecast valid on 08/25/2014 at 0600 MDT

Freezing level.................. 14685 ft MSL (9398 ft AGL)
Convective condensation level... 14953 ft MSL (9666 ft AGL)
Lifted condensation level....... 14578 ft MSL (9291 ft AGL)
Lifted index.................... -1.6
K index......................... +28.9

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  -62.4 -80.3   245   36   18   1.6   0.9      M     M       M      M    M
 45000  -59.5 -75.1   250   59   30   2.9   1.6      M     M       M      M    M
 40000  -54.9 -66.8   245   71   37   6.8   3.7      M     M       M      M    M
 38000  -51.0 -59.8   240   67   35   6.5   3.5      M     M       M      M    M
 36000  -47.2 -53.0   235   64   33   6.5   3.6      M     M       M      M    M
 34000  -42.8 -45.0   235   60   31   7.7   4.2      M     M       M      M    M
 32000  -37.6 -35.7   240   54   28   7.7   4.2      M     M       M      M    M
 30000  -33.5 -28.3   240   46   24   6.6   3.6   42.0 107.6    11.2      M    M
 29000  -31.5 -24.7   240   41   21   6.6   3.6   40.8 105.4    10.4      M    M
 28000  -29.6 -21.3   245   37   19   7.1   3.9   39.8 103.6     9.7      M    M
 27000  -27.2 -17.0   245   38   20   8.0   4.4   39.0 102.1     9.2      M    M
 26000  -24.7 -12.5   245   39   20   8.0   4.4   38.3 100.9     8.8      M    M
 25000  -22.3  -8.1   240   41   21   8.1   4.4   37.8 100.0     8.5      M    M
 24000  -20.0  -4.0   240   41   21   7.6   4.2   37.0  98.5     7.9      M    M
 23000  -17.7   0.1   240   39   20   7.6   4.2   36.1  97.1     7.3      M    M
 22000  -15.4   4.3   240   38   20   7.6   4.2   35.4  95.8     6.9      M    M
 21000  -13.1   8.4   240   36   19   7.6   4.2   34.6  94.3     6.2      M    M
 20000  -10.9  12.4   235   33   17   7.7   4.2   33.9  93.0     5.6      M    M
 19500   -9.7  14.5   235   32   16   7.8   4.3   33.6  92.4     5.3      M    M
 19000   -8.6  16.5   235   30   16   8.1   4.4   33.3  91.9     5.1      M    M
 18500   -7.4  18.7   230   29   15   8.1   4.5   33.0  91.4     4.8      M    M
 18000   -6.2  20.8   230   27   14   8.0   4.4   32.7  90.9     4.6      M    M
 17500   -5.3  22.5   235   25   13   5.6   3.1   32.2  89.9     4.1      M    M
 17000   -4.5  23.9   245   25   13   5.9   3.2   31.5  88.7     3.4      M    M
 16500   -3.7  25.3   255   25   13   6.0   3.3   30.9  87.5     2.8      M    M
 16000   -2.4  27.7   260   24   12   6.0   3.3   29.9  85.8     1.8      M    M
 15500   -1.5  29.3   260   23   12   7.6   4.2   29.4  84.9     1.3      M    M
 15000   -0.5  31.1   260   21   11   7.7   4.2   29.0  84.3     0.9      M    M
 14500    0.6  33.1   255   19   10   8.4   4.6   28.7  83.7     0.5      M    M
 14000    1.9  35.4   255   18    9   8.7   4.8   28.5  83.4     0.3      M    M
 13500    3.1  37.6   255   16    8   9.0   4.9   28.4  83.1     0.1      M    M
 13000    4.4  39.9   255   15    8   9.3   5.1   28.3  83.0    -0.1    639  3.2
 12500    5.8  42.4   255   14    7   9.0   4.9   28.3  82.9    -0.1    583  3.0
 12000    7.0  44.6   250   12    6   8.0   4.4   28.0  82.4    -0.4    532  2.7
 11500    8.2  46.8   250   11    5   7.9   4.3   27.7  81.9    -0.7    482  2.4
 11000    9.3  48.7   250    9    5   7.0   3.8   27.4  81.3    -1.0    434  2.2
 10500   10.4  50.7   250    8    4   4.5   2.5   27.0  80.5    -1.4    387  2.0
 10250   10.6  51.1   255    7    4   4.8   2.6   26.4  79.6    -1.9    373  1.9
 10000   11.2  52.2   255    7    3   8.9   4.9   26.3  79.3    -2.1    348  1.8
  9750   11.8  53.2   255    6    3   8.5   4.7   26.2  79.1    -2.2    322  1.6
  9500   12.4  54.3   255    5    3   7.9   4.3   26.1  79.0    -2.3    296  1.5
  9250   12.9  55.2   260    5    2   6.0   3.3   25.9  78.6    -2.5    273  1.4
  9000   13.4  56.1   265    4    2   6.4   3.5   25.6  78.0    -2.8    253  1.3
  8750   13.9  57.0   275    4    2   7.1   3.9   25.4  77.6    -3.0    229  1.2
  8500   14.4  57.9   285    4    2   6.8   3.7   25.1  77.3    -3.2    206  1.0
  8250   15.0  59.0   300    3    2   6.7   3.7   24.9  76.8    -3.4    183  0.9
  8000   15.5  59.9   320    4    2   6.6   3.6   24.7  76.4    -3.6    160  0.8
  7750   16.0  60.8   330    4    2   6.6   3.6   24.4  76.0    -3.8    137  0.7
  7500   16.6  61.9   340    4    2   6.4   3.5   24.2  75.5    -4.1    113  0.6
  7250   17.0  62.6   340    5    3   6.2   3.4   23.9  75.1    -4.3     91  0.5
  7000   17.5  63.5   340    6    3   6.5   3.6   23.7  74.6    -4.5     69  0.4
  6750   18.0  64.4   340    7    3   4.8   2.6   23.4  74.1    -4.8     47  0.2
  6500   18.2  64.8   340    7    4   0.3   0.2   22.8  73.1    -5.3     33  0.2
  6250   18.1  64.6   340    8    4  -2.1  -1.2   22.0  71.6    -6.2     31  0.2
  6000   17.9  64.2   345    8    4   0.3   0.2   21.2  70.1    -7.1     28  0.1
  5750   17.9  64.2   345   10    5  -3.8  -2.1   20.4  68.8    -7.9     21  0.1
  5500   16.9  62.4   335    6    3 -15.6  -8.5   19.0  66.2    -9.6     44  0.2

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

           08/25/2014 at 0900 MDT          |       08/25/2014 at 1200 MDT
                                           |
K index... +28.4  LI... -1.2               | K index... +25.7  LI... -1.4
CAPE... +350.0  CIN... -21.5               | CAPE... +395.3  CIN... -72.4
                                           |
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 -62.3 -80.1  250  42 21   1.5   0.8 | -62.8 -81.0  245  46 23   2.0   1.1
 45000 -59.5 -75.1  245  64 33   2.9   1.6 | -59.2 -74.6  245  65 33   3.4   1.9
 40000 -54.9 -66.8  240  69 35   6.6   3.6 | -53.6 -64.5  240  68 35   5.9   3.2
 38000 -51.1 -60.0  240  65 33   6.4   3.5 | -50.1 -58.2  240  66 34   5.8   3.2
 36000 -47.3 -53.1  240  60 31   6.4   3.5 | -46.6 -51.9  240  64 33   5.8   3.2
 34000 -42.5 -44.5  240  54 28   7.3   4.0 | -42.7 -44.9  245  59 30   6.7   3.7
 32000 -38.1 -36.6  240  48 25   7.2   4.0 | -38.7 -37.7  245  53 27   6.7   3.7
 30000 -34.2 -29.6  240  42 22   6.2   3.4 | -34.7 -30.5  240  47 24   6.7   3.7
 29000 -32.4 -26.3  240  40 20   6.3   3.4 | -32.7 -26.9  240  45 23   6.7   3.7
 28000 -30.5 -22.9  240  37 19   7.3   4.0 | -30.7 -23.3  235  42 22   6.8   3.8
 27000 -27.8 -18.0  240  37 19   9.1   5.0 | -27.5 -17.5  230  39 20   9.0   5.0
 26000 -25.1 -13.2  235  37 19   9.1   5.0 | -24.8 -12.6  230  37 19   9.1   5.0
 25000 -22.4  -8.3  235  38 19   9.3   5.1 | -22.0  -7.6  225  36 18   8.9   4.9
 24000 -19.9  -3.8  235  37 19   7.8   4.3 | -19.7  -3.5  225  34 17   7.4   4.1
 23000 -17.5   0.5  235  36 19   7.8   4.3 | -17.5   0.5  230  32 17   7.4   4.1
 22000 -15.2   4.6  235  35 18   7.8   4.3 | -15.3   4.5  235  31 16   7.4   4.1
 21000 -13.0   8.6  235  33 17   7.3   4.0 | -13.1   8.4  235  28 14   7.5   4.1
 20000 -10.8  12.6  230  31 16   7.4   4.0 | -10.9  12.4  230  25 13   7.5   4.1
 19500  -9.7  14.5  230  30 15   7.4   4.1 |  -9.7  14.5  225  24 12   7.5   4.1
 19000  -8.6  16.5  230  29 15   7.7   4.2 |  -8.6  16.5  225  23 12   7.6   4.2
 18500  -7.5  18.5  230  28 14   7.7   4.2 |  -7.5  18.5  225  23 12   7.6   4.2
 18000  -6.3  20.7  230  26 14   7.4   4.1 |  -6.4  20.5  230  22 11   7.6   4.1
 17500  -5.5  22.1  235  24 13   5.4   3.0 |  -5.3  22.5  235  21 11   7.5   4.1
 17000  -4.7  23.5  240  22 11   5.6   3.0 |  -4.3  24.3  240  21 11   7.6   4.2
 16500  -3.3  26.1  250  21 11   7.4   4.1 |  -3.3  26.1  245  21 11   6.6   3.6
 16000  -2.3  27.9  255  22 11   7.6   4.2 |  -2.3  27.9  245  20 10   6.8   3.7
 15500  -1.4  29.5  255  21 11   6.9   3.8 |  -1.4  29.5  245  19 10   7.3   4.0
 15000  -0.4  31.3  255  19 10   6.9   3.8 |  -0.3  31.5  240  18  9   7.6   4.2
 14500   0.6  33.1  250  17  9   7.9   4.4 |   0.8  33.4  240  17  9   7.9   4.3
 14000   1.8  35.2  250  15  8   8.3   4.5 |   2.6  36.7  240  16  8   8.6   4.7
 13500   2.9  37.2  250  13  7   8.2   4.5 |   3.8  38.8  235  15  8   8.6   4.7
 13000   4.1  39.4  250  12  6   8.1   4.5 |   5.0  41.0  230  14  7   8.7   4.7
 12500   5.3  41.5  250  10  5   8.3   4.6 |   6.2  43.2  230  13  7   8.6   4.7
 12000   6.6  43.9  245   9  5   8.7   4.8 |   7.5  45.5  225  13  6   8.6   4.7
 11500   7.9  46.2  240   8  4   8.2   4.5 |   8.7  47.7  220  12  6   8.3   4.6
 11000   8.9  48.0  240   6  3   6.6   3.6 |   9.8  49.6  215  10  5   7.5   4.1
 10500   9.9  49.8  245   5  3   4.1   2.3 |  11.0  51.8  210   9  5   3.4   1.9
 10250  10.1  50.2  245   5  3   3.8   2.1 |  11.0  51.8  210   9  5   3.4   1.9
 10000  10.6  51.1  245   5  2   8.2   4.5 |  11.6  52.9  205   8  4   8.9   4.9
  9750  11.2  52.2  250   4  2   8.8   4.8 |  12.1  53.8  200   7  4   7.9   4.4
  9500  11.9  53.4  255   4  2   7.3   4.0 |  12.7  54.9  195   6  3   6.4   3.5
  9250  12.3  54.1  265   3  2   4.8   2.7 |  13.1  55.6  195   5  3   4.0   2.2
  9000  12.7  54.9  270   3  2   5.6   3.1 |  13.4  56.1  195   4  2   4.9   2.7
  8750  13.2  55.8  290   3  1   6.8   3.7 |  13.8  56.8  190   3  2   5.5   3.0
  8500  13.7  56.7  310   3  1   5.8   3.2 |  14.2  57.6  185   2  1   4.6   2.5
  8250  14.2  57.6  330   4  2   5.2   2.9 |  14.6  58.3  180   1  1   3.9   2.1
  8000  14.6  58.3  340   5  3   5.0   2.7 |  14.9  58.8  000   0  0   3.8   2.1
  7750  15.0  59.0  345   6  3   4.2   2.3 |  15.2  59.4  020   2  1   3.8   2.1
  7500  15.3  59.5  350   8  4   3.4   1.9 |  15.6  60.1  015   3  1   6.9   3.8
  7250  15.4  59.7  355   9  5   2.9   1.6 |  16.1  61.0  015   4  2   9.0   4.9
  7000  15.6  60.1  360  10  5   3.4   1.9 |  16.6  61.9  010   4  2   8.4   4.6
  6750  15.8  60.4  360  12  6   3.1   1.7 |  17.2  63.0  010   5  2   9.6   5.3
  6500  15.9  60.6  360  11  6   1.9   1.1 |  17.9  64.2  010   4  2  11.0   6.0
  6250  15.9  60.6  355   9  5   1.3   0.7 |  18.7  65.7  010   5  2  11.6   6.3
  6000  16.0  60.8  350   8  4   2.7   1.5 |  19.6  67.3  010   5  2  10.2   5.6
  5750  16.4  61.5  345   7  4   9.9   5.4 |  20.4  68.7  010   4  2  15.4   8.5
  5500  17.4  63.3  340   6  3  17.8   9.7 |  22.0  71.6  010   4  2  27.8  15.3

           08/25/2014 at 1500 MDT          |       08/25/2014 at 1800 MDT
                                           |
K index... +32.6  LI... -4.2               | K index... +31.8  LI... -3.2
CAPE... +1005.2  CIN... -27.5              | CAPE... +697.2  CIN... -2.3
                                           |
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 -63.4 -82.1  240  45 23   1.4   0.8 | -63.4 -82.1  240  43 22   1.2   0.6
 45000 -60.1 -76.2  245  67 35   4.3   2.4 | -60.8 -77.4  245  63 32   3.4   1.8
 40000 -53.2 -63.8  250  69 36   5.4   3.0 | -55.0 -67.0  260  66 34   6.8   3.7
 38000 -50.0 -58.0  250  68 35   5.4   3.0 | -50.8 -59.4  255  56 29   7.0   3.8
 36000 -46.7 -52.1  250  66 34   5.4   3.0 | -46.6 -51.9  250  47 24   6.8   3.7
 34000 -42.5 -44.5  250  61 31   7.4   4.0 | -41.7 -43.1  250  43 22   8.6   4.7
 32000 -38.1 -36.6  250  55 28   7.4   4.1 | -36.5 -33.7  245  40 21   8.4   4.6
 30000 -33.4 -28.1  245  50 26   8.2   4.5 | -31.6 -24.9  245  35 18   8.2   4.5
 29000 -31.0 -23.8  240  47 24   8.2   4.5 | -29.2 -20.6  245  32 17   8.2   4.5
 28000 -28.5 -19.3  235  45 23   8.1   4.5 | -26.1 -15.0  245  29 15   7.5   4.1
 27000 -25.7 -14.3  235  42 22   7.5   4.1 | -24.0 -11.2  240  29 15   7.3   4.0
 26000 -23.5 -10.3  230  39 20   7.5   4.1 | -21.8  -7.2  240  29 15   7.4   4.0
 25000 -21.3  -6.3  230  36 19   7.5   4.1 | -19.6  -3.3  240  28 14   7.3   4.0
 24000 -19.1  -2.4  235  34 18   7.3   4.0 | -17.6   0.3  235  28 15   6.7   3.7
 23000 -16.9   1.6  240  33 17   7.4   4.0 | -15.7   3.7  235  29 15   6.8   3.7
 22000 -14.8   5.4  245  31 16   7.1   3.9 | -13.7   7.3  230  29 15   6.7   3.7
 21000 -12.8   9.0  245  29 15   6.5   3.6 | -11.8  10.8  225  30 15   6.3   3.5
 20000 -10.9  12.4  240  27 14   6.5   3.6 | -10.0  14.0  220  30 16   6.4   3.5
 19500 -10.0  14.0  240  25 13   6.4   3.5 |  -9.1  15.6  215  31 16   6.3   3.5
 19000  -9.0  15.8  235  25 13   7.2   4.0 |  -8.2  17.2  215  30 16   6.6   3.6
 18500  -8.0  17.6  235  24 13   7.2   4.0 |  -7.2  19.0  210  29 15   6.6   3.6
 18000  -6.9  19.6  235  24 13   7.2   3.9 |  -6.2  20.8  205  28 15   6.5   3.6
 17500  -5.9  21.4  235  24 12   7.1   3.9 |  -5.3  22.5  200  28 14   6.3   3.5
 17000  -4.9  23.2  235  23 12   7.1   3.9 |  -4.4  24.1  195  27 14   6.3   3.4
 16500  -3.9  25.0  230  22 11   7.6   4.2 |  -3.5  25.7  195  27 14   6.7   3.7
 16000  -2.8  27.0  230  21 11   7.6   4.2 |  -2.5  27.5  190  26 13   6.7   3.7
 15500  -1.8  28.8  230  21 11   8.0   4.4 |  -1.5  29.3  185  25 13   6.8   3.7
 15000  -0.6  30.9  225  20 10   8.2   4.5 |  -0.6  30.9  185  23 12   6.8   3.8
 14500   0.6  33.1  220  20 10   8.4   4.6 |   0.4  32.7  180  21 11   6.9   3.8
 14000   2.5  36.5  215  18  9   8.8   4.8 |   1.9  35.4  180  18  9   6.9   3.8
 13500   3.7  38.7  210  17  9   9.1   5.0 |   2.9  37.2  175  15  8   6.9   3.8
 13000   5.1  41.2  205  17  9   9.2   5.1 |   3.8  38.8  165  12  6   6.9   3.8
 12500   6.4  43.5  205  16  8   9.2   5.0 |   4.8  40.6  150   9  4   7.7   4.2
 12000   7.8  46.0  205  15  8   9.0   5.0 |   6.0  42.8  135   7  4   8.7   4.8
 11500   9.1  48.4  200  15  8   8.7   4.7 |   7.2  45.0  110   6  3   9.1   5.0
 11000  10.3  50.5  195  13  7   7.7   4.2 |   8.6  47.5  100   6  3   9.6   5.3
 10500  11.5  52.7  195  11  6   4.1   2.3 |  10.1  50.2  095   6  3   5.2   2.8
 10250  11.6  52.9  190  10  5   3.4   1.8 |  10.3  50.5  095   6  3   6.8   3.7
 10000  12.0  53.6  180   8  4   7.7   4.2 |  11.2  52.2  090   6  3  13.7   7.5
  9750  12.5  54.5  165   6  3   6.7   3.7 |  12.1  53.8  090   6  3  12.5   6.9
  9500  12.9  55.2  135   4  2   6.5   3.5 |  13.1  55.6  085   6  3  10.3   5.7
  9250  13.4  56.1  120   4  2   6.7   3.7 |  13.7  56.7  085   6  3   7.7   4.2
  9000  13.9  57.0  110   4  2   9.0   5.0 |  14.3  57.7  080   6  3  10.2   5.6
  8750  14.6  58.3  105   4  2   9.9   5.4 |  15.1  59.2  080   6  3  11.2   6.2
  8500  15.3  59.5  100   4  2   9.9   5.4 |  15.9  60.6  075   6  3  10.4   5.7
  8250  16.1  61.0  095   4  2  10.3   5.7 |  16.7  62.1  075   6  3   9.9   5.4
  8000  16.8  62.2  095   4  2   9.9   5.4 |  17.4  63.3  070   6  3   9.9   5.4
  7750  17.5  63.5  095   4  2   9.6   5.3 |  18.1  64.6  070   6  3   9.7   5.3
  7500  18.3  64.9  095   4  2  10.1   5.5 |  18.9  66.0  065   6  3  10.0   5.5
  7250  19.0  66.2  095   4  2  10.6   5.8 |  19.6  67.3  065   6  3  10.5   5.8
  7000  19.8  67.6  090   4  2   9.9   5.4 |  20.4  68.7  060   7  3   9.6   5.3
  6750  20.5  68.9  090   4  2   9.7   5.3 |  21.1  70.0  060   7  3   8.8   4.8
  6500  21.3  70.3  090   3  2  10.7   5.9 |  21.8  71.2  055   7  3   9.8   5.4
  6250  22.1  71.8  090   3  2  12.1   6.6 |  22.5  72.5  055   7  3  10.8   5.9
  6000  22.9  73.2  090   3  2   8.6   4.7 |  23.3  73.9  050   7  3   9.4   5.2
  5750  23.6  74.5  090   3  2  13.3   7.3 |  24.0  75.2  050   7  3  10.1   5.5
  5500  25.2  77.4  085   3  2  30.6  16.8 |  24.8  76.6  045   7  3  14.8   8.1
________________________________________________________________________________

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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