Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231405
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0805 MDT Saturday, August 23, 2014

This forecast is for Saturday, August 23, 2014:

If the trigger temperature of 73.6 F/23.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 812 ft/min (4.1 m/s)
   Maximum height of thermals.................. 14884 ft MSL (9599 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
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................. 9936 ft MSL (4651 ft AGL)
Thermal soaring outlook for Sunday 08/24....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16619 ft MSL (11334 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 18343 ft MSL (13058 ft AGL)
Wave soaring outlook for Sunday 08/24.......... Good

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 06:19:05 / 19:45:38 MDT
Total possible sunshine........... 13 hr 26 min 33 sec (806 min 33 sec)
Altitude of sun at 13:01:58 MDT... 61.50 degrees

Upper air data from rawinsonde observation taken on 08/23/2014 at 0600 MDT

Freezing level.................. 14261 ft MSL (8976 ft AGL)
Convective condensation level... 12110 ft MSL (6825 ft AGL)
Lifted condensation level....... 12958 ft MSL (7673 ft AGL)
Lifted index.................... -3.8
K index......................... +26.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -63.8 -82.8   215   33   17  -5.7  -3.1   86.1 186.9    34.0      M    M
 45000  -59.5 -75.1   210   43   22   4.2   2.3   69.0 156.2    25.8      M    M
 40000  -51.1 -60.0   195   54   28   5.2   2.8   59.2 138.6    21.0      M    M
 38000  -46.7 -52.1   190   62   32   7.8   4.3   57.0 134.5    20.1      M    M
 36000  -42.0 -43.6   185   59   30   8.1   4.4   55.4 131.8    19.5      M    M
 34000  -38.7 -37.7   195   35   18   5.1   2.8   51.9 125.4    17.4      M    M
 32000  -35.2 -31.4   245   27   14   6.3   3.5   47.6 117.7    14.7      M    M
 30000  -32.0 -25.6   235   26   13   5.6   3.0   44.2 111.5    12.5      M    M
 29000  -30.1 -22.2   250   25   13   6.2   3.4   42.8 109.1    11.6      M    M
 28000  -27.7 -17.9   215   22   11   8.6   4.7   42.1 107.9    11.2      M    M
 27000  -25.3 -13.5   210   24   12   7.9   4.3   41.5 106.7    10.8      M    M
 26000  -23.0  -9.4   205   27   14   7.6   4.1   40.6 105.1    10.2      M    M
 25000  -20.8  -5.4   200   29   15   7.7   4.2   39.9 103.8     9.6      M    M
 24000  -18.6  -1.5   205   22   11   7.5   4.1   39.1 102.3     9.1      M    M
 23000  -16.0   3.2   210   18    9   6.9   3.8   38.6 101.5     8.7      M    M
 22000  -14.1   6.6   215   15    8   8.3   4.5   37.5  99.5     7.8      M    M
 21000  -11.7  10.9   230   12    6   8.3   4.5   36.9  98.5     7.4      M    M
 20000   -9.4  15.1   235   13    7   7.6   4.2   36.2  97.2     6.8      M    M
 19500   -8.3  17.1   230   16    8   6.7   3.7   35.7  96.3     6.5      M    M
 19000   -7.3  18.9   230   19   10   7.4   4.0   35.2  95.4     6.0      M    M
 18500   -6.2  20.8   230   20   10   8.1   4.5   34.9  94.9     5.7      M    M
 18000   -5.2  22.6   230   21   11   5.4   2.9   34.4  93.9     5.3      M    M
 17500   -4.4  24.1   230   20   10   5.6   3.1   33.7  92.6     4.7      M    M
 17000   -3.6  25.5   225   18    9   6.1   3.3   33.0  91.3     4.0      M    M
 16500   -3.0  26.6   225   16    8   1.2   0.6   32.0  89.6     3.1      M    M
 16000   -2.3  27.9   220   14    7   5.3   2.9   30.4  86.7     1.7      M    M
 15500   -1.6  29.1   230   13    7   4.7   2.6   29.6  85.4     1.0      M    M
 15000   -1.1  30.0   240   12    6   3.7   2.0   28.7  83.6     0.0      M    M
 14500   -0.4  31.3   245   12    6   7.7   4.2   27.9  82.3    -0.7    777  3.9
 14000    0.9  33.6   255   12    6   8.3   4.5   27.7  81.9    -0.9    725  3.7
 13500    2.1  35.8   255   10    5   8.3   4.6   27.5  81.4    -1.2    674  3.4
 13000    3.3  37.9   255    9    5   8.3   4.6   27.2  81.0    -1.4    622  3.2
 12500    4.6  40.3   250    7    4   8.3   4.6   27.0  80.7    -1.6    570  2.9
 12000    5.8  42.4   250    6    3   8.3   4.6   26.9  80.3    -1.8    519  2.6
 11500    7.0  44.6   265    6    3   8.3   4.6   26.6  79.9    -2.1    467  2.4
 11000    8.3  46.9   280    7    3   8.3   4.6   26.4  79.4    -2.4    415  2.1
 10500    9.5  49.1   290    7    4   8.1   4.4   26.1  79.1    -2.6    363  1.8
 10250   10.1  50.2   295    8    4   8.2   4.5   26.0  78.8    -2.7    337  1.7
 10000   10.6  51.1   285    7    3   5.4   3.0   25.8  78.5    -2.9    314  1.6
  9750   10.8  51.4   275    6    3   3.2   1.7   25.3  77.6    -3.5    301  1.5
  9500   11.0  51.8   255    5    2   3.1   1.7   24.8  76.7    -4.1    288  1.5
  9250   11.2  52.2   235    5    2   5.9   3.3   24.4  75.8    -4.6    276  1.4
  9000   11.9  53.4   215    5    3   9.4   5.1   24.3  75.7    -4.6    247  1.3
  8750   12.6  54.7   215    4    2   7.5   4.1   24.2  75.5    -4.7    219  1.1
  8500   13.0  55.4   210    3    1   6.6   3.6   23.9  75.1    -5.0    199  1.0
  8250   13.3  55.9   205    2    1   5.5   3.0   23.7  74.6    -5.4    182  0.9
  8000   13.6  56.5   190    1    1   4.0   2.2   23.3  73.9    -5.9    167  0.8
  7750   13.8  56.8   195    2    1   3.8   2.1   22.8  73.0    -6.4    152  0.8
  7500   14.1  57.4   195    3    2   4.4   2.4   22.3  72.2    -6.9    137  0.7
  7250   14.4  57.9   195    5    2   2.3   1.3   21.9  71.4    -7.4    122  0.6
  7000   14.3  57.7   195    6    3  -1.4  -0.8   21.2  70.1    -8.2    115  0.6
  6750   14.2  57.6   195    6    3   1.5   0.8   20.4  68.7    -9.0    111  0.6
  6500   14.5  58.1   195    6    3   6.7   3.7   20.0  67.9    -9.5     95  0.5
  6250   15.0  59.0   200    5    3   6.8   3.7   19.8  67.6    -9.8     73  0.4
  6000   15.5  59.9   200    5    3   9.1   5.0   19.6  67.3   -10.0     51  0.3
  5750   16.0  60.8   200    3    2  -0.0  -0.0   19.4  66.9   -10.3     29  0.1
  5500   15.1  59.2   200    2    1 -23.7 -13.0   17.7  63.9   -12.0     48  0.2

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

           08/23/2014 at 0900 MDT          |       08/23/2014 at 1200 MDT
                                           |
K index... +22.1  LI... -0.2               | K index... +24.8  LI... -1.3
CAPE... +37.8  CIN... -71.3                | CAPE... +63.7  CIN... -70.7
                                           |
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 -62.2 -80.0  200  30 15   1.0   0.5 | -61.6 -78.9  200  31 16   1.1   0.6
 45000 -58.8 -73.8  195  46 24   5.2   2.8 | -58.6 -73.5  210  40 21   4.2   2.3
 40000 -50.9 -59.6  200  50 26   5.8   3.2 | -52.2 -62.0  230  39 20   6.1   3.3
 38000 -47.5 -53.5  210  47 24   5.8   3.2 | -48.6 -55.5  235  42 22   5.9   3.3
 36000 -44.0 -47.2  215  43 22   5.8   3.2 | -45.0 -49.0  245  45 23   6.0   3.3
 34000 -40.2 -40.4  220  40 21   6.5   3.6 | -40.5 -40.9  250  47 24   8.1   4.5
 32000 -36.3 -33.3  230  37 19   6.5   3.6 | -35.6 -32.1  255  49 25   8.1   4.5
 30000 -31.6 -24.9  230  36 18   7.3   4.0 | -30.4 -22.7  260  47 24   7.6   4.2
 29000 -29.4 -20.9  230  35 18   7.3   4.0 | -28.1 -18.6  260  45 23   7.6   4.2
 28000 -27.2 -17.0  230  35 18   7.5   4.1 | -25.8 -14.4  260  43 22   7.4   4.1
 27000 -24.9 -12.8  230  33 17   8.0   4.4 | -23.8 -10.8  255  41 21   6.6   3.6
 26000 -22.5  -8.5  230  31 16   8.0   4.4 | -21.9  -7.4  250  39 20   6.6   3.6
 25000 -20.1  -4.2  230  29 15   8.1   4.4 | -19.9  -3.8  240  38 19   6.6   3.6
 24000 -17.9  -0.2  230  27 14   6.9   3.8 | -18.0  -0.4  240  37 19   6.2   3.4
 23000 -15.9   3.4  225  24 12   7.0   3.8 | -16.2   2.8  235  36 18   6.3   3.5
 22000 -13.8   7.2  225  22 11   7.1   3.9 | -14.4   6.1  235  35 18   6.6   3.6
 21000 -11.8  10.8  225  20 10   6.9   3.8 | -12.5   9.5  235  33 17   6.3   3.5
 20000  -9.8  14.4  230  18  9   7.0   3.8 | -10.7  12.7  235  32 17   6.4   3.5
 19500  -8.7  16.3  230  17  9   7.0   3.8 |  -9.8  14.4  235  32 16   6.4   3.5
 19000  -7.7  18.1  235  16  8   6.8   3.7 |  -8.8  16.2  230  31 16   6.9   3.8
 18500  -6.8  19.8  230  16  8   6.5   3.6 |  -7.8  18.0  230  31 16   7.6   4.2
 18000  -5.8  21.6  225  17  9   6.5   3.6 |  -6.6  20.1  230  30 15   7.8   4.3
 17500  -4.9  23.2  225  17  9   5.9   3.2 |  -5.6  21.9  230  28 15   6.6   3.6
 17000  -4.0  24.8  230  17  9   5.9   3.2 |  -4.6  23.7  230  27 14   6.6   3.6
 16500  -3.2  26.2  230  17  9   5.6   3.1 |  -3.7  25.3  230  25 13   6.4   3.5
 16000  -2.5  27.5  230  17  9   5.3   2.9 |  -2.8  27.0  230  23 12   6.1   3.3
 15500  -1.7  28.9  230  17  9   5.2   2.9 |  -1.9  28.6  230  21 11   6.1   3.3
 15000  -0.5  31.1  230  15  8   5.8   3.2 |  -0.3  31.5  235  18  9   7.8   4.3
 14500   0.3  32.5  230  14  7   6.1   3.3 |   0.9  33.6  240  15  8   8.1   4.4
 14000   1.3  34.3  230  13  6   6.7   3.7 |   2.1  35.8  245  14  7   8.7   4.8
 13500   2.2  36.0  230  11  6   6.8   3.7 |   3.4  38.1  250  13  7   8.7   4.8
 13000   3.3  37.9  235  10  5   7.5   4.1 |   4.6  40.3  260  14  7   7.7   4.2
 12500   4.3  39.7  240   9  4   7.2   3.9 |   5.7  42.3  265  16  8   8.3   4.5
 12000   5.6  42.1  245   8  4   9.5   5.2 |   6.5  43.7  265  17  9   3.6   2.0
 11500   6.9  44.4  255   9  5   9.5   5.2 |   7.0  44.6  265  17  9   4.1   2.2
 11000   8.2  46.8  265  10  5   6.9   3.8 |   7.6  45.7  265  16  8   4.2   2.3
 10500   9.2  48.6  265  13  7   6.6   3.6 |   8.2  46.8  260  13  7   4.1   2.3
 10250   9.7  49.5  270  14  7   9.3   5.1 |   8.5  47.3  255  11  6   7.4   4.1
 10000  10.4  50.7  270  16  8   8.4   4.6 |   9.1  48.4  250   9  5   8.7   4.8
  9750  10.8  51.4  270  17  9   5.1   2.8 |   9.7  49.5  240   8  4   7.3   4.0
  9500  11.2  52.2  275  18  9   6.1   3.3 |  10.2  50.4  235   6  3   7.5   4.1
  9250  11.6  52.9  275  19 10   5.6   3.1 |  10.7  51.3  220   5  2   8.1   4.5
  9000  12.1  53.8  275  19 10   6.1   3.4 |  11.4  52.5  215   4  2   9.7   5.3
  8750  12.5  54.5  275  18  9   6.7   3.7 |  12.1  53.8  215   4  2  10.1   5.6
  8500  13.0  55.4  275  17  9   6.6   3.6 |  12.9  55.2  210   4  2  10.0   5.5
  8250  13.5  56.3  275  16  8   6.8   3.8 |  13.6  56.5  210   4  2  10.3   5.7
  8000  14.0  57.2  280  14  7   7.0   3.8 |  14.4  57.9  210   4  2  10.2   5.6
  7750  14.5  58.1  280  13  7   7.1   3.9 |  15.1  59.2  210   4  2   9.7   5.3
  7500  15.0  59.0  280  12  6   6.7   3.7 |  15.8  60.4  210   4  2   9.9   5.4
  7250  15.4  59.7  285  11  5   5.6   3.1 |  16.6  61.9  210   3  2  10.8   5.9
  7000  15.7  60.3  290   9  5   5.1   2.8 |  17.4  63.3  210   3  2  10.7   5.9
  6750  16.1  61.0  290   8  4   4.1   2.3 |  18.1  64.6  210   3  2   8.9   4.9
  6500  16.3  61.3  300   6  3   5.1   2.8 |  18.8  65.8  210   3  2   9.6   5.3
  6250  16.7  62.1  295   5  2   7.0   3.9 |  19.6  67.3  210   3  2  11.4   6.3
  6000  17.1  62.8  285   3  2   6.6   3.6 |  20.5  68.9  215   3  1  10.8   5.9
  5750  17.6  63.7  260   2  1   8.6   4.7 |  21.3  70.3  215   3  1  11.6   6.3
  5500  18.4  65.1  230   1  1  14.7   8.1 |  22.3  72.1  215   3  1  19.3  10.6

           08/23/2014 at 1500 MDT          |       08/23/2014 at 1800 MDT
                                           |
K index... +28.1  LI... -2.1               | K index... +27.7  LI... -1.7
CAPE... +254.7  CIN... -2.5                | CAPE... +258.6  CIN... -10.6
                                           |
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 -60.7 -77.3  210  33 17   1.6   0.9 | -60.2 -76.4  230  35 18   1.0   0.6
 45000 -57.9 -72.2  220  44 23   2.2   1.2 | -57.8 -72.0  230  50 26   3.4   1.9
 40000 -54.1 -65.4  240  46 24   7.9   4.3 | -52.3 -62.1  225  44 22   4.9   2.7
 38000 -49.6 -57.3  235  50 26   7.5   4.1 | -49.5 -57.1  235  50 26   4.8   2.6
 36000 -45.1 -49.2  235  54 28   7.5   4.1 | -46.6 -51.9  240  57 29   4.9   2.7
 34000 -40.7 -41.3  235  52 27   7.4   4.1 | -42.3 -44.1  245  56 29   8.0   4.4
 32000 -36.2 -33.2  240  50 26   7.4   4.1 | -37.5 -35.5  245  51 26   8.1   4.4
 30000 -30.9 -23.6  250  48 25   8.2   4.5 | -32.4 -26.3  245  48 25   8.7   4.8
 29000 -28.5 -19.3  250  47 24   8.2   4.5 | -29.2 -20.6  250  46 24   8.7   4.8
 28000 -26.0 -14.8  255  47 24   8.0   4.4 | -26.6 -15.9  250  45 23   8.4   4.6
 27000 -23.8 -10.8  250  42 22   7.6   4.2 | -24.3 -11.7  250  45 23   7.6   4.2
 26000 -21.5  -6.7  245  37 19   7.6   4.2 | -22.0  -7.6  255  45 23   7.7   4.2
 25000 -19.3  -2.7  240  32 17   7.7   4.2 | -19.7  -3.5  255  45 23   7.7   4.2
 24000 -17.3   0.9  235  33 17   6.2   3.4 | -17.7   0.1  250  43 22   6.7   3.7
 23000 -15.6   3.9  240  36 19   6.2   3.4 | -15.7   3.7  245  39 20   6.7   3.7
 22000 -13.8   7.2  240  40 20   6.3   3.4 | -13.8   7.2  240  36 19   6.9   3.8
 21000 -11.9  10.6  240  39 20   6.3   3.5 | -12.0  10.4  235  34 18   6.1   3.4
 20000 -10.1  13.8  235  37 19   6.3   3.5 | -10.2  13.6  240  32 17   6.1   3.4
 19500  -9.2  15.4  235  36 19   6.4   3.5 |  -9.3  15.3  240  32 16   6.1   3.4
 19000  -8.3  17.1  235  35 18   6.4   3.5 |  -8.4  16.9  240  31 16   6.1   3.4
 18500  -7.3  18.9  235  34 18   6.4   3.5 |  -7.5  18.5  240  28 14   6.1   3.4
 18000  -6.4  20.5  235  34 17   6.4   3.5 |  -6.6  20.1  240  25 13   6.1   3.3
 17500  -5.5  22.1  235  33 17   6.4   3.5 |  -5.7  21.7  235  22 11   6.5   3.6
 17000  -4.5  23.9  240  32 16   6.4   3.5 |  -4.8  23.4  230  20 10   6.5   3.6
 16500  -3.6  25.5  240  31 16   6.3   3.5 |  -3.8  25.2  220  19 10   6.8   3.7
 16000  -2.7  27.1  240  29 15   6.3   3.5 |  -2.8  27.0  220  19 10   7.1   3.9
 15500  -1.8  28.8  245  26 14   6.3   3.5 |  -1.8  28.8  215  18  9   7.1   3.9
 15000  -0.4  31.3  240  24 12   6.7   3.7 |  -0.8  30.6  215  18  9   6.7   3.7
 14500   0.6  33.1  235  22 11   6.7   3.7 |   0.7  33.3  210  17  9   6.9   3.8
 14000   1.6  34.9  230  20 10   6.8   3.7 |   1.7  35.1  205  15  8   7.2   3.9
 13500   2.6  36.7  225  18  9   6.9   3.8 |   2.8  37.0  205  13  7   7.2   3.9
 13000   3.6  38.5  220  16  8   7.5   4.1 |   3.8  38.8  200  11  5   7.6   4.2
 12500   4.7  40.5  210  13  7   7.3   4.0 |   4.9  40.8  200   8  4   7.4   4.1
 12000   5.9  42.6  200  11  6  10.5   5.8 |   6.2  43.2  200   6  3  10.0   5.5
 11500   7.4  45.3  200  11  5  10.5   5.7 |   7.6  45.7  200   5  3   9.9   5.4
 11000   8.8  47.8  200  10  5   8.2   4.5 |   9.0  48.2  200   5  2   8.9   4.9
 10500  10.0  50.0  195   9  5   9.9   5.5 |  10.3  50.5  205   4  2  10.7   5.9
 10250  10.8  51.4  195   8  4  11.2   6.2 |  11.2  52.2  205   4  2  11.7   6.4
 10000  11.6  52.9  190   7  4   9.2   5.0 |  11.9  53.4  215   3  2   9.3   5.1
  9750  12.2  54.0  185   6  3   8.9   4.9 |  12.6  54.7  235   2  1   9.0   4.9
  9500  12.8  55.0  180   5  3   9.0   4.9 |  13.3  55.9  260   2  1   9.2   5.1
  9250  13.5  56.3  170   4  2   8.9   4.9 |  13.9  57.0  295   2  1   8.6   4.7
  9000  14.1  57.4  170   4  2   9.6   5.3 |  14.5  58.1  320   3  2   8.4   4.6
  8750  14.9  58.8  165   4  2  10.3   5.6 |  15.2  59.4  330   5  2   8.9   4.9
  8500  15.6  60.1  165   4  2  10.0   5.5 |  15.8  60.4  340   6  3   8.7   4.7
  8250  16.4  61.5  160   3  2  10.7   5.9 |  16.4  61.5  340   8  4   9.7   5.3
  8000  17.2  63.0  160   3  2  10.0   5.5 |  17.2  63.0  340   9  4  10.0   5.5
  7750  17.9  64.2  160   3  2   8.9   4.9 |  17.9  64.2  340   9  5   9.3   5.1
  7500  18.6  65.5  155   3  1   9.5   5.2 |  18.6  65.5  340  10  5   9.6   5.3
  7250  19.3  66.7  155   3  1  11.1   6.1 |  19.3  66.7  340  10  5  10.2   5.6
  7000  20.1  68.2  155   2  1  11.2   6.1 |  20.1  68.2  340  10  5  10.2   5.6
  6750  20.9  69.6  150   2  1   9.1   5.0 |  20.8  69.4  340  10  5   9.3   5.1
  6500  21.6  70.9  150   2  1   9.5   5.2 |  21.5  70.7  340  11  5   9.6   5.3
  6250  22.3  72.1  145   2  1  10.9   6.0 |  22.2  72.0  340  11  6  10.4   5.7
  6000  23.2  73.8  140   2  1  10.8   5.9 |  23.0  73.4  340  11  6  10.4   5.7
  5750  24.0  75.2  140   1  1  10.8   5.9 |  23.8  74.8  340  11  6  10.1   5.5
  5500  24.9  76.8  135   1  1  17.5   9.6 |  24.5  76.1  340  10  5  12.4   6.8
________________________________________________________________________________

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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