Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271152
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0552 MDT Wednesday, August 27, 2014

This forecast is for Wednesday, August 27, 2014:

If the trigger temperature of 72.6 F/22.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 459 ft/min (2.3 m/s)
   Maximum height of thermals.................. 11262 ft MSL (5975 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7801 ft MSL (2514 ft AGL)
Thermal soaring outlook for Thursday 08/28..... 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....................... 40248 ft MSL (34961 ft AGL)
Wave soaring outlook for Thursday 08/28........ Poor

Remarks...

Sunrise/Sunset.................... 06:22:50 / 19:39:42 MDT
Total possible sunshine........... 13 hr 16 min 52 sec (796 min 52 sec)
Altitude of sun at 13:00:51 MDT... 60.11 degrees

Upper air data from numerical model forecast valid on 08/27/2014 at 0600 MDT

Freezing level.................. 15016 ft MSL (9729 ft AGL)
Convective condensation level... 11234 ft MSL (5947 ft AGL)
Lifted condensation level....... 11227 ft MSL (5940 ft AGL)
Lifted index.................... -1.9
K index......................... +30.9

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  -63.9 -83.0   225   38   20  -0.4  -0.2      M     M       M      M    M
 45000  -61.9 -79.4   225   50   26   5.6   3.1      M     M       M      M    M
 40000  -53.5 -64.3   230   59   30   6.1   3.3      M     M       M      M    M
 38000  -49.8 -57.6   230   58   30   6.1   3.3      M     M       M      M    M
 36000  -46.2 -51.2   225   57   29   6.0   3.3      M     M       M      M    M
 34000  -41.3 -42.3   220   52   27   8.6   4.7      M     M       M      M    M
 32000  -35.5 -31.9   220   45   23   8.5   4.7      M     M       M      M    M
 30000  -30.7 -23.3   220   40   21   8.0   4.4   45.3 113.5    15.8      M    M
 29000  -28.3 -18.9   220   37   19   8.0   4.4   44.6 112.3    15.5      M    M
 28000  -25.9 -14.6   215   35   18   7.7   4.2   44.1 111.3    15.2      M    M
 27000  -23.7 -10.7   215   33   17   7.5   4.1   43.1 109.5    14.5      M    M
 26000  -21.5  -6.7   215   31   16   7.5   4.1   42.2 108.0    14.0      M    M
 25000  -19.3  -2.7   215   29   15   7.5   4.1   41.5 106.7    13.6      M    M
 24000  -17.2   1.0   215   27   14   7.0   3.8   40.4 104.8    12.8      M    M
 23000  -15.1   4.8   210   25   13   7.0   3.9   39.4 103.0    12.0      M    M
 22000  -13.1   8.4   210   23   12   7.0   3.9   38.5 101.4    11.4      M    M
 21000  -11.1  12.0   205   22   11   6.8   3.8   37.4  99.4    10.5      M    M
 20000   -9.1  15.6   205   21   11   6.9   3.8   36.4  97.5     9.7      M    M
 19500   -8.1  17.4   205   20   10   7.0   3.8   35.9  96.7     9.3      M    M
 19000   -7.2  19.0   205   20   10   5.9   3.3   35.4  95.8     8.8      M    M
 18500   -6.3  20.7   210   19   10   5.8   3.2   34.7  94.5     8.3      M    M
 18000   -5.5  22.1   215   18    9   5.9   3.2   34.1  93.3     7.7      M    M
 17500   -4.6  23.7   220   17    9   6.5   3.6   33.4  92.2     7.2      M    M
 17000   -3.6  25.5   220   16    8   6.5   3.6   32.9  91.2     6.7      M    M
 16500   -2.7  27.1   220   15    8   6.1   3.3   32.3  90.2     6.2      M    M
 16000   -1.9  28.6   220   14    7   6.0   3.3   31.7  89.0     5.6      M    M
 15500   -0.6  30.9   215   12    6   5.8   3.2   30.7  87.3     4.8      M    M
 15000    0.2  32.4   210   11    5   5.9   3.2   30.1  86.1     4.1      M    M
 14500    1.0  33.8   205    9    5   5.3   2.9   29.4  85.0     3.5      M    M
 14000    1.7  35.1   200    8    4   5.2   2.8   28.6  83.6     2.8      M    M
 13500    2.4  36.3   195    8    4   5.8   3.2   27.9  82.2     2.0      M    M
 13000    3.3  37.9   190    7    4   6.5   3.6   27.4  81.2     1.5      M    M
 12500    4.2  39.6   185    7    4   6.9   3.8   26.8  80.3     0.9      M    M
 12000    5.3  41.5   185    7    4   7.6   4.2   26.5  79.6     0.5      M    M
 11500    6.4  43.5   180    7    4   7.5   4.1   26.1  79.0     0.1      M    M
 11000    7.4  45.3   180    7    4   7.1   3.9   25.7  78.3    -0.3    430  2.2
 10500    8.5  47.3   175    7    4   4.7   2.6   25.4  77.6    -0.7    384  1.9
 10250    8.7  47.7   175    7    4   4.3   2.4   24.8  76.7    -1.2    369  1.9
 10000    9.2  48.6   175    7    4   8.3   4.6   24.6  76.3    -1.4    346  1.8
  9750    9.8  49.6   175    7    4   8.5   4.7   24.5  76.1    -1.5    321  1.6
  9500   10.4  50.7   175    7    3   7.6   4.1   24.4  75.9    -1.6    295  1.5
  9250   10.9  51.6   175    6    3   5.9   3.2   24.2  75.5    -1.9    273  1.4
  9000   11.4  52.5   170    6    3   6.9   3.8   23.9  75.0    -2.1    253  1.3
  8750   11.9  53.4   170    5    3   7.9   4.4   23.7  74.7    -2.3    228  1.2
  8500   12.5  54.5   170    5    2   7.5   4.1   23.6  74.4    -2.5    204  1.0
  8250   13.0  55.4   170    4    2   7.3   4.0   23.4  74.1    -2.7    180  0.9
  8000   13.6  56.5   175    4    2   7.3   4.0   23.2  73.7    -2.9    157  0.8
  7750   14.1  57.4   175    4    2   7.3   4.0   23.0  73.4    -3.0    133  0.7
  7500   14.7  58.5   180    4    2   8.0   4.4   22.8  73.1    -3.2    108  0.5
  7250   15.3  59.5   180    5    2   8.5   4.7   22.7  72.9    -3.3     82  0.4
  7000   15.9  60.6   180    5    3   8.4   4.6   22.6  72.7    -3.4     57  0.3
  6750   16.5  61.7   180    5    3   6.2   3.4   22.5  72.4    -3.6     32  0.2
  6500   16.8  62.2   185    5    3   3.8   2.1   22.1  71.7    -4.0     16  0.1
  6250   17.0  62.6   190    5    3   2.4   1.3   21.6  70.9    -4.6      2  0.0
  6000   17.2  63.0   190    5    3   6.8   3.7   21.1  70.0    -5.1      M    M
  5750   17.7  63.9   200    5    3   2.7   1.5   20.9  69.7    -5.3      M    M
  5500   17.0  62.6   190    3    2 -16.3  -9.0   19.7  67.5    -6.8      M    M

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

           08/27/2014 at 0900 MDT          |       08/27/2014 at 1200 MDT
                                           |
K index... +30.2  LI... -1.2               | K index... +25.0  LI... -1.3
CAPE... +169.6  CIN... -62.9               | CAPE... +182.8  CIN... -19.1
                                           |
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 -63.3 -81.9  230  36 19  -0.3  -0.2 | -63.1 -81.6  235  32 17   0.6   0.3
 45000 -61.5 -78.7  225  48 25   4.7   2.6 | -60.6 -77.1  225  45 23   4.2   2.3
 40000 -54.1 -65.4  220  52 27   6.9   3.8 | -53.8 -64.8  210  51 26   7.3   4.0
 38000 -49.9 -57.8  220  50 26   6.9   3.8 | -49.4 -56.9  205  47 24   7.4   4.1
 36000 -45.7 -50.3  215  47 24   6.9   3.8 | -44.9 -48.8  200  43 22   7.3   4.0
 34000 -41.1 -42.0  210  47 24   7.9   4.4 | -40.1 -40.2  200  41 21   8.2   4.5
 32000 -35.7 -32.3  205  49 25   7.6   4.2 | -34.6 -30.3  205  39 20   8.2   4.5
 30000 -30.4 -22.7  205  43 22   9.1   5.0 | -30.1 -22.2  200  39 20   7.4   4.1
 29000 -27.7 -17.9  205  39 20   9.1   5.0 | -27.8 -18.0  200  40 21   7.5   4.1
 28000 -25.1 -13.2  210  35 18   7.2   4.0 | -25.6 -14.1  200  40 21   7.8   4.3
 27000 -23.1  -9.6  210  34 17   6.4   3.5 | -23.3  -9.9  200  40 21   8.0   4.4
 26000 -21.2  -6.2  215  33 17   6.4   3.5 | -20.9  -5.6  200  39 20   8.0   4.4
 25000 -19.3  -2.7  220  31 16   6.5   3.5 | -18.5  -1.3  200  39 20   8.2   4.5
 24000 -17.2   1.0  215  28 15   7.6   4.2 | -16.7   1.9  205  36 18   5.6   3.0
 23000 -14.9   5.2  210  25 13   7.7   4.2 | -14.9   5.2  210  32 16   5.6   3.1
 22000 -12.7   9.1  205  23 12   7.5   4.1 | -13.2   8.2  220  28 15   5.8   3.2
 21000 -10.8  12.6  205  21 11   6.3   3.4 | -11.2  11.8  220  27 14   6.9   3.8
 20000  -9.0  15.8  210  20 10   6.3   3.5 |  -9.2  15.4  220  26 13   7.0   3.8
 19500  -8.1  17.4  210  19 10   6.3   3.5 |  -8.2  17.2  220  25 13   7.1   3.9
 19000  -7.2  19.0  210  18  9   6.2   3.4 |  -7.2  19.0  220  24 13   6.8   3.7
 18500  -6.3  20.7  210  17  9   6.2   3.4 |  -6.3  20.7  225  22 11   6.9   3.8
 18000  -5.4  22.3  205  16  8   6.2   3.4 |  -5.3  22.5  225  20 10   6.9   3.8
 17500  -4.5  23.9  205  16  8   6.0   3.3 |  -4.4  24.1  225  19 10   6.1   3.3
 17000  -3.7  25.3  210  16  8   6.0   3.3 |  -3.5  25.7  230  17  9   6.2   3.4
 16500  -2.8  27.0  210  16  8   5.7   3.1 |  -2.7  27.1  230  16  8   5.5   3.0
 16000  -1.6  29.1  215  15  8   5.8   3.2 |  -1.5  29.3  230  14  7   5.6   3.1
 15500  -0.8  30.6  215  14  7   4.9   2.7 |  -0.8  30.6  235  13  7   4.9   2.7
 15000  -0.1  31.8  215  14  7   4.9   2.7 |  -0.1  31.8  240  12  6   4.9   2.7
 14500   0.7  33.3  215  13  6   6.2   3.4 |   0.6  33.1  240  11  6   5.5   3.0
 14000   1.6  34.9  215  12  6   6.7   3.7 |   1.4  34.5  245  11  6   5.8   3.2
 13500   2.6  36.7  215  11  6   7.0   3.8 |   2.2  36.0  250  10  5   6.1   3.4
 13000   3.6  38.5  215  10  5   7.2   4.0 |   3.1  37.6  260  10  5   6.5   3.6
 12500   4.7  40.5  210   9  5   6.9   3.8 |   4.0  39.2  265  10  5   6.7   3.7
 12000   5.5  41.9  210   8  4   6.1   3.3 |   5.1  41.2  275  10  5   7.3   4.0
 11500   6.4  43.5  210   8  4   6.2   3.4 |   6.1  43.0  280  11  6   7.3   4.0
 11000   7.3  45.1  215   7  3   6.6   3.6 |   7.2  45.0  285  11  6   7.3   4.0
 10500   8.2  46.8  215   5  3   4.2   2.3 |   8.3  46.9  290  12  6   5.0   2.7
 10250   8.4  47.1  220   5  3   3.2   1.7 |   8.6  47.5  290  12  6   4.5   2.5
 10000   8.8  47.8  225   4  2   7.3   4.0 |   9.1  48.4  295  11  6   8.4   4.6
  9750   9.4  48.9  230   3  2   8.1   4.5 |   9.7  49.5  295  11  6   8.8   4.9
  9500   9.9  49.8  245   3  1   6.8   3.7 |  10.3  50.5  300  11  6   7.3   4.0
  9250  10.3  50.5  260   2  1   4.7   2.6 |  10.7  51.3  305  10  5   5.1   2.8
  9000  10.7  51.3  275   2  1   7.2   4.0 |  11.1  52.0  305   9  5   6.6   3.6
  8750  11.4  52.5  295   2  1   9.6   5.3 |  11.7  53.1  310   9  5   8.1   4.5
  8500  12.0  53.6  315   2  1   8.2   4.5 |  12.2  54.0  315   8  4   7.0   3.8
  8250  12.6  54.7  315   2  1   7.5   4.1 |  12.7  54.9  325   7  4   6.1   3.4
  8000  13.2  55.8  315   3  1   7.8   4.3 |  13.1  55.6  335   7  4   6.8   3.7
  7750  13.7  56.7  320   3  2   7.5   4.1 |  13.5  56.3  350   7  3   7.8   4.3
  7500  14.2  57.6  330   3  2   4.8   2.6 |  14.1  57.4  360   7  3   9.2   5.1
  7250  14.5  58.1  335   5  2   3.2   1.7 |  14.8  58.6  005   7  3  10.1   5.6
  7000  14.7  58.5  335   6  3   3.5   1.9 |  15.5  59.9  005   7  4   9.7   5.3
  6750  15.0  59.0  340   8  4   3.5   1.9 |  16.2  61.2  005   7  4   9.9   5.4
  6500  15.2  59.4  340   8  4   4.3   2.3 |  17.0  62.6  010   7  3  10.6   5.8
  6250  15.4  59.7  340   8  4   4.0   2.2 |  17.8  64.0  010   7  3  10.3   5.6
  6000  15.7  60.3  340   8  4   5.5   3.0 |  18.6  65.5  010   7  3  11.9   6.5
  5750  16.2  61.2  340   8  4  10.8   5.9 |  19.6  67.3  010   6  3  17.4   9.6
  5500  17.2  63.0  340   7  4  15.0   8.3 |  21.1  70.0  010   7  3  21.6  11.8

           08/27/2014 at 1500 MDT          |       08/27/2014 at 1800 MDT
                                           |
K index... +23.3  LI... -2.9               | K index... +28.4  LI... -3.0
CAPE... +459.1  CIN... -9.5                | CAPE... +459.8  CIN... -0.9
                                           |
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 -62.8 -81.0  230  35 18   0.9   0.5 | -62.4 -80.3  225  27 14   0.8   0.4
 45000 -59.8 -75.6  225  49 25   4.6   2.5 | -59.5 -75.1  210  41 21   4.9   2.7
 40000 -52.6 -62.7  210  50 26   6.7   3.7 | -52.0 -61.6  205  50 26   6.4   3.5
 38000 -48.6 -55.5  205  50 26   6.7   3.7 | -48.2 -54.8  205  50 26   6.4   3.5
 36000 -44.5 -48.1  200  50 26   6.7   3.7 | -44.3 -47.7  200  49 25   6.4   3.5
 34000 -40.1 -40.2  200  48 25   7.4   4.1 | -39.5 -39.1  200  48 25   7.3   4.0
 32000 -35.1 -31.2  205  45 23   7.3   4.0 | -35.1 -31.2  205  47 24   7.3   4.0
 30000 -30.2 -22.4  205  44 23   8.3   4.5 | -30.9 -23.6  205  46 24   7.0   3.8
 29000 -27.7 -17.9  205  43 22   8.3   4.5 | -28.8 -19.8  205  46 24   7.0   3.8
 28000 -25.2 -13.4  205  43 22   7.6   4.1 | -26.7 -16.1  210  46 24   7.1   3.9
 27000 -23.1  -9.6  210  41 21   7.1   3.9 | -24.5 -12.1  210  44 23   7.2   4.0
 26000 -21.0  -5.8  210  39 20   7.1   3.9 | -22.4  -8.3  210  43 22   7.3   4.0
 25000 -18.9  -2.0  210  38 19   7.3   4.0 | -20.2  -4.4  210  41 21   7.4   4.1
 24000 -17.0   1.4  215  36 18   6.1   3.3 | -18.2  -0.8  215  39 20   6.5   3.6
 23000 -15.2   4.6  215  34 17   6.1   3.4 | -16.3   2.7  220  37 19   6.5   3.6
 22000 -13.3   8.1  220  32 17   6.1   3.3 | -14.4   6.1  225  35 18   6.6   3.6
 21000 -11.6  11.1  220  31 16   5.7   3.2 | -12.5   9.5  230  34 17   6.2   3.4
 20000  -9.8  14.4  220  29 15   5.8   3.2 | -10.7  12.7  230  33 17   6.3   3.4
 19500  -9.0  15.8  220  29 15   5.7   3.1 |  -9.8  14.4  235  32 17   6.3   3.4
 19000  -8.1  17.4  220  28 14   6.4   3.5 |  -8.8  16.2  235  31 16   6.3   3.5
 18500  -7.1  19.2  225  28 14   6.6   3.6 |  -7.9  17.8  235  28 14   6.4   3.5
 18000  -6.2  20.8  225  28 15   6.5   3.6 |  -7.0  19.4  235  24 12   6.4   3.5
 17500  -5.3  22.5  225  27 14   5.9   3.2 |  -6.1  21.0  235  22 11   6.1   3.4
 17000  -4.5  23.9  230  26 14   6.0   3.3 |  -5.2  22.6  230  21 11   6.1   3.4
 16500  -3.1  26.4  230  24 13   6.8   3.7 |  -3.9  25.0  230  20 10   6.4   3.5
 16000  -2.2  28.0  235  23 12   6.8   3.7 |  -2.9  26.8  230  19 10   6.4   3.5
 15500  -1.2  29.8  235  21 11   7.2   4.0 |  -2.0  28.4  230  18  9   6.5   3.6
 15000  -0.2  31.6  240  19 10   7.3   4.0 |  -1.1  30.0  225  16  8   6.5   3.6
 14500   0.7  33.3  240  16  8   7.3   4.0 |  -0.1  31.8  220  14  7   6.9   3.8
 14000   1.7  35.1  245  14  7   7.3   4.0 |   0.9  33.6  220  13  7   7.1   3.9
 13500   2.7  36.9  250  12  6   7.5   4.1 |   1.9  35.4  215  12  6   6.9   3.8
 13000   3.8  38.8  250  11  6   7.6   4.2 |   2.9  37.2  215  10  5   6.6   3.6
 12500   4.9  40.8  255  10  5   7.6   4.2 |   3.8  38.8  210   8  4   6.6   3.6
 12000   6.0  42.8  260   9  5   7.6   4.2 |   4.7  40.5  215   6  3   6.7   3.7
 11500   7.1  44.8  265   9  5   7.4   4.0 |   5.7  42.3  225   3  1   6.9   3.8
 11000   8.1  46.6  275   8  4   6.4   3.5 |   6.7  44.1  270   2  1   7.9   4.3
 10500   9.1  48.4  285   7  4   3.8   2.1 |   7.8  46.0  320   2  1   4.1   2.2
 10250   9.2  48.6  290   7  3   4.3   2.4 |   8.0  46.4  325   2  1   6.5   3.6
 10000   9.8  49.6  295   5  3   8.7   4.8 |   8.9  48.0  325   3  1  13.8   7.6
  9750  10.3  50.5  315   3  2   7.9   4.3 |   9.8  49.6  320   3  1  12.9   7.1
  9500  10.8  51.4  355   3  1   7.9   4.3 |  10.7  51.3  320   3  2  11.3   6.2
  9250  11.4  52.5  010   3  1   7.8   4.3 |  11.4  52.5  320   3  2   8.1   4.4
  9000  12.0  53.6  010   3  1   9.8   5.4 |  12.0  53.6  320   3  2   9.7   5.3
  8750  12.7  54.9  015   3  2  11.2   6.2 |  12.8  55.0  320   3  2  11.2   6.2
  8500  13.5  56.3  015   3  2  10.2   5.6 |  13.6  56.5  320   3  2  10.4   5.7
  8250  14.2  57.6  015   3  2   9.4   5.2 |  14.4  57.9  320   4  2   9.9   5.4
  8000  14.9  58.8  015   3  2   9.7   5.3 |  15.1  59.2  320   4  2   9.9   5.4
  7750  15.6  60.1  015   3  2   9.9   5.4 |  15.9  60.6  320   4  2   9.9   5.4
  7500  16.4  61.5  015   3  2  10.2   5.6 |  16.6  61.9  320   4  2  10.1   5.5
  7250  17.2  63.0  015   3  2  10.4   5.7 |  17.4  63.3  320   4  2  10.5   5.8
  7000  17.9  64.2  015   3  2  10.1   5.6 |  18.1  64.6  315   4  2   9.8   5.4
  6750  18.7  65.7  015   3  2  10.1   5.5 |  18.8  65.8  315   4  2   9.1   5.0
  6500  19.4  66.9  015   3  2  10.5   5.8 |  19.5  67.1  315   5  2  10.1   5.5
  6250  20.2  68.4  015   3  2  11.1   6.1 |  20.3  68.5  315   5  2  11.2   6.1
  6000  21.0  69.8  015   3  2   9.8   5.4 |  21.1  70.0  315   5  3   9.3   5.1
  5750  21.8  71.2  015   3  2  15.0   8.2 |  21.8  71.2  315   5  3  10.4   5.7
  5500  23.4  74.1  015   3  2  27.1  14.8 |  22.7  72.9  315   5  3  17.0   9.3
________________________________________________________________________________

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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