Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 211318
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0718 MDT Thursday, August 21, 2014

This forecast is for Thursday, August 21, 2014:

If the trigger temperature of 77.8 F/25.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1025 ft/min (5.2 m/s)
   Maximum height of thermals.................. 16899 ft MSL (11614 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 0945 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................. 12910 ft MSL (7624 ft AGL)
Thermal soaring outlook for Friday 08/22....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17559 ft MSL (12274 ft AGL)
Wave soaring outlook for Friday 08/22.......... Poor

Remarks...

Sunrise/Sunset.................... 06:17:12 / 19:48:31 MDT
Total possible sunshine........... 13 hr 31 min 19 sec (811 min 19 sec)
Altitude of sun at 13:02:28 MDT... 62.17 degrees

Upper air data from rawinsonde observation taken on 08/21/2014 at 0600 MDT

Freezing level.................. 15201 ft MSL (9916 ft AGL)
Convective condensation level... 14428 ft MSL (9143 ft AGL)
Lifted condensation level....... 15209 ft MSL (9924 ft AGL)
Lifted index.................... -1.0
K index......................... +22.1

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  -68.5 -91.3   250   39   20  -7.0  -3.9   77.9 172.2    27.3      M    M
 45000  -60.7 -77.3   230   59   31   7.5   4.1   66.5 151.7    22.2      M    M
 40000  -51.2 -60.2   230   64   33   4.7   2.6   57.7 135.8    17.8      M    M
 38000  -47.2 -53.0   235   61   32  -3.1  -1.7   55.0 131.0    16.5      M    M
 36000  -42.6 -44.7   240   59   30   8.9   4.9   53.2 127.8    15.6      M    M
 34000  -38.0 -36.4   235   56   29   7.2   3.9   51.5 124.6    14.7      M    M
 32000  -33.3 -27.9   225   52   27   8.7   4.8   50.0 121.9    14.0      M    M
 30000  -28.6 -19.5   230   52   27   5.7   3.1   48.5 119.4    13.2      M    M
 29000  -26.9 -16.4   230   49   25   6.6   3.6   47.0 116.6    12.1      M    M
 28000  -24.2 -11.6   230   46   24   8.8   4.8   46.6 115.9    12.1      M    M
 27000  -21.0  -5.8   235   42   22   4.6   2.5   45.9 114.7    11.7      M    M
 26000  -19.1  -2.4   235   39   20   7.5   4.1   44.7 112.5    10.9      M    M
 25000  -17.2   1.0   235   36   18   4.8   2.6   43.5 110.2    10.0      M    M
 24000  -15.3   4.5   240   30   15   7.6   4.1   42.1 107.9     9.0      M    M
 23000  -13.1   8.4   235   28   14   6.4   3.5   41.3 106.4     8.5      M    M
 22000  -11.5  11.3   225   26   13   5.8   3.2   39.8 103.6     7.2      M    M
 21000   -9.7  14.5   210   28   14   5.3   2.9   38.3 101.0     6.1      M    M
 20000   -8.2  17.2   220   28   14   5.3   2.9   36.8  98.2     4.8      M    M
 19500   -7.4  18.7   225   28   14   4.4   2.4   36.0  96.8     4.2      M    M
 19000   -7.1  19.2   225   27   14   3.4   1.9   34.7  94.5     3.0      M    M
 18500   -7.7  18.1   220   31   16  -1.7  -0.9   32.7  90.8     1.0      M    M
 18000   -6.7  19.9   215   35   18   8.9   4.9   32.3  90.1     0.5      M    M
 17500   -5.4  22.3   215   34   18   8.8   4.8   32.1  89.9     0.3      M    M
 17000   -4.2  24.4   220   33   17   8.3   4.5   31.9  89.4     0.1      M    M
 16500   -3.0  26.6   220   32   16   8.3   4.5   31.6  88.9    -0.1    991  5.0
 16000   -1.7  28.9   225   31   16   8.5   4.7   31.4  88.5    -0.3    939  4.8
 15500   -0.7  30.7   230   29   15   5.2   2.9   31.0  87.8    -0.8    894  4.5
 15000    0.2  32.4   235   26   13   8.2   4.5   30.4  86.8    -1.3    852  4.3
 14500    1.5  34.7   240   24   12   8.0   4.4   30.2  86.3    -1.5    799  4.1
 14000    2.8  37.0   250   21   11   7.3   4.0   29.9  85.8    -1.7    746  3.8
 13500    4.1  39.4   250   19   10   6.2   3.4   29.1  84.4    -2.6    684  3.5
 13000    5.1  41.2   250   17    9   8.1   4.5   28.7  83.6    -3.0    638  3.2
 12500    6.3  43.3   250   15    8   8.0   4.4   28.4  83.1    -3.3    589  3.0
 12000    7.4  45.3   250   14    7   8.0   4.4   28.1  82.6    -3.6    540  2.7
 11500    8.6  47.5   250   12    6   8.1   4.4   27.8  82.1    -4.0    491  2.5
 11000    9.7  49.5   255   11    6   8.1   4.4   27.6  81.6    -4.3    441  2.2
 10500   10.9  51.6   255    9    5   8.0   4.4   27.3  81.2    -4.6    392  2.0
 10250   11.5  52.7   260    9    5   7.7   4.2   27.2  80.9    -4.8    368  1.9
 10000   12.0  53.6   270    9    5   7.5   4.1   27.0  80.6    -5.0    344  1.7
  9750   12.6  54.7   280    9    5   7.6   4.2   26.8  80.3    -5.2    320  1.6
  9500   13.1  55.6   290   10    5   7.6   4.2   26.7  80.0    -5.3    295  1.5
  9250   13.7  56.7   300   11    6   7.6   4.2   26.5  79.7    -5.5    271  1.4
  9000   14.2  57.6   305   12    6   7.6   4.2   26.3  79.4    -5.7    247  1.3
  8750   14.8  58.6   300   11    6   7.6   4.2   26.2  79.1    -5.9    223  1.1
  8500   15.3  59.5   295   11    6   7.5   4.1   26.0  78.8    -6.1    199  1.0
  8250   15.9  60.6   290   10    5   7.9   4.3   25.8  78.5    -6.3    175  0.9
  8000   16.5  61.7   285   10    5   6.4   3.5   25.7  78.2    -6.4    151  0.8
  7750   16.7  62.1   270    8    4   4.1   2.3   25.3  77.5    -6.9    136  0.7
  7500   16.9  62.4   250    7    4   4.2   2.3   24.9  76.7    -7.5    123  0.6
  7250   17.2  63.0   230    7    4   4.4   2.4   24.4  76.0    -8.0    108  0.6
  7000   17.5  63.5   210    8    4   4.4   2.4   24.0  75.3    -8.4     92  0.5
  6750   17.7  63.9   205    8    4   4.4   2.4   23.6  74.5    -8.9     76  0.4
  6500   18.0  64.4   200    9    5   4.6   2.5   23.2  73.8    -9.3     59  0.3
  6250   18.3  64.9   200    9    5   3.9   2.1   22.8  73.1    -9.8     43  0.2
  6000   18.6  65.5   195   10    5   6.6   3.6   22.4  72.4   -10.2     27  0.1
  5750   18.9  66.0   195    7    4  -3.5  -1.9   22.1  71.7   -10.7     11  0.1
  5500   17.5  63.5   195    3    2 -31.8 -17.5   20.0  68.0   -12.9     46  0.2

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

           08/21/2014 at 0900 MDT          |       08/21/2014 at 1200 MDT
                                           |
K index... +20.9  LI... -0.4               | K index... +17.4  LI... -0.3
CAPE... +35.4  CIN... -11.5                | CAPE... +1.1  CIN... -8.7
                                           |
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 -63.9 -83.0  225  35 18   0.9   0.5 | -64.3 -83.7  220  38 20   1.7   0.9
 45000 -60.2 -76.4  230  53 27   5.6   3.1 | -60.3 -76.5  225  53 27   5.0   2.7
 40000 -51.7 -61.1  235  65 33   6.8   3.7 | -51.9 -61.4  235  62 32   7.6   4.2
 38000 -47.5 -53.5  235  61 31   6.9   3.8 | -47.3 -53.1  235  63 32   7.6   4.2
 36000 -43.4 -46.1  235  57 29   6.8   3.7 | -42.8 -45.0  240  63 32   7.6   4.2
 34000 -38.4 -37.1  235  57 29   7.5   4.1 | -38.2 -36.8  235  58 30   7.7   4.2
 32000 -33.9 -29.0  235  57 30   7.4   4.0 | -33.6 -28.5  235  53 27   7.5   4.1
 30000 -29.5 -21.1  235  52 27   7.3   4.0 | -29.2 -20.6  230  50 26   7.4   4.1
 29000 -27.4 -17.3  235  49 25   7.3   4.0 | -27.0 -16.6  230  48 25   7.4   4.1
 28000 -25.2 -13.4  235  46 24   7.4   4.1 | -24.8 -12.6  230  46 24   7.2   4.0
 27000 -22.9  -9.2  235  43 22   7.5   4.1 | -22.2  -8.0  230  42 22   6.9   3.8
 26000 -20.7  -5.3  235  40 20   7.5   4.1 | -20.2  -4.4  230  39 20   6.9   3.8
 25000 -18.4  -1.1  235  36 19   7.5   4.1 | -18.1  -0.6  230  36 19   6.9   3.8
 24000 -16.3   2.7  235  34 17   6.9   3.8 | -16.1   3.0  230  34 18   6.8   3.7
 23000 -14.2   6.4  235  32 16   6.9   3.8 | -14.0   6.8  235  32 17   6.8   3.7
 22000 -12.2  10.0  235  30 15   6.8   3.8 | -12.0  10.4  235  30 16   6.3   3.5
 21000 -10.5  13.1  235  27 14   5.3   2.9 | -10.5  13.1  240  28 14   5.3   2.9
 20000  -8.9  16.0  235  25 13   5.3   2.9 |  -8.9  16.0  240  26 13   5.3   2.9
 19500  -8.1  17.4  235  24 12   5.3   2.9 |  -8.2  17.2  245  25 13   5.3   2.9
 19000  -7.3  18.9  235  22 12   5.3   2.9 |  -7.3  18.9  245  23 12   6.0   3.3
 18500  -6.5  20.3  240  21 11   5.3   2.9 |  -6.4  20.5  245  22 12   6.0   3.3
 18000  -5.7  21.7  240  20 10   5.4   2.9 |  -5.5  22.1  250  21 11   6.2   3.4
 17500  -4.9  23.2  235  20 10   5.8   3.2 |  -4.6  23.7  250  21 11   6.5   3.6
 17000  -4.1  24.6  235  19 10   5.9   3.2 |  -3.7  25.3  250  20 10   6.6   3.6
 16500  -2.8  27.0  230  19 10   6.8   3.7 |  -2.7  27.1  250  19 10   6.6   3.6
 16000  -1.9  28.6  225  19 10   6.7   3.7 |  -1.8  28.8  250  19 10   6.6   3.6
 15500  -0.8  30.6  225  19 10   8.3   4.6 |  -0.8  30.6  245  18  9   6.9   3.8
 15000   0.4  32.7  225  19 10   8.3   4.6 |   0.2  32.4  245  18  9   7.1   3.9
 14500   1.5  34.7  225  18  9   7.8   4.3 |   1.3  34.3  240  18  9   7.2   4.0
 14000   2.6  36.7  220  16  8   7.5   4.1 |   2.9  37.2  235  17  9   7.5   4.1
 13500   3.7  38.7  220  15  8   7.1   3.9 |   4.0  39.2  230  16  8   7.4   4.0
 13000   4.6  40.3  215  13  7   6.7   3.7 |   5.1  41.2  230  15  8   7.3   4.0
 12500   5.5  41.9  205  12  6   7.1   3.9 |   6.1  43.0  225  15  8   7.5   4.1
 12000   6.6  43.9  205  10  5   8.1   4.5 |   7.1  44.8  220  14  7   7.9   4.3
 11500   7.7  45.9  205   9  5   7.8   4.3 |   8.2  46.8  215  13  7   7.7   4.2
 11000   8.8  47.8  210   7  4   6.1   3.3 |   9.2  48.6  215  12  6   6.9   3.8
 10500   9.8  49.6  225   5  2   3.7   2.0 |  10.2  50.4  215  10  5   3.2   1.7
 10250  10.0  50.0  230   4  2   5.3   2.9 |  10.3  50.5  215  10  5   4.4   2.4
 10000  10.7  51.3  250   4  2  10.3   5.6 |  11.0  51.8  220   8  4  10.3   5.7
  9750  11.5  52.7  270   4  2   9.8   5.4 |  11.8  53.2  230   7  4   9.1   5.0
  9500  12.2  54.0  285   5  3   8.9   4.9 |  12.5  54.5  240   6  3   8.3   4.6
  9250  12.8  55.0  295   6  3   7.0   3.9 |  13.0  55.4  250   5  2   7.4   4.0
  9000  13.4  56.1  300   8  4   8.7   4.8 |  13.7  56.7  255   4  2   9.3   5.1
  8750  14.1  57.4  300  10  5  10.5   5.7 |  14.4  57.9  265   3  2  10.4   5.7
  8500  14.8  58.6  305  11  6   8.7   4.8 |  15.1  59.2  285   2  1   9.5   5.2
  8250  15.4  59.7  305  13  7   7.3   4.0 |  15.7  60.3  290   1  1   9.0   4.9
  8000  15.9  60.6  305  15  8   6.8   3.7 |  16.3  61.3  000   0  0   9.3   5.1
  7750  16.4  61.5  305  16  8   5.8   3.2 |  16.9  62.4  000   0  0   9.4   5.1
  7500  16.8  62.2  305  16  8   5.7   3.1 |  17.6  63.7  000   0  0   9.9   5.4
  7250  17.2  63.0  305  15  8   5.5   3.0 |  18.4  65.1  000   0  0  10.5   5.8
  7000  17.5  63.5  305  14  7   5.7   3.1 |  19.1  66.4  085   1  0   9.7   5.3
  6750  17.9  64.2  305  13  7   5.8   3.2 |  19.8  67.6  085   1  0   9.5   5.2
  6500  18.3  64.9  305  11  6   5.3   2.9 |  20.6  69.1  000   0  0  10.7   5.9
  6250  18.6  65.5  305   8  4   5.7   3.1 |  21.4  70.5  075   1  0  12.1   6.6
  6000  18.9  66.0  305   5  3   3.8   2.1 |  22.3  72.1  070   1  0   8.7   4.8
  5750  19.1  66.4  295   2  1   8.5   4.7 |  22.9  73.2  070   1  0  13.6   7.4
  5500  20.2  68.4  295   2  1  22.2  12.2 |  24.5  76.1  075   1  0  30.9  17.0

           08/21/2014 at 1500 MDT          |       08/21/2014 at 1800 MDT
                                           |
K index... +22.7  LI... -1.8               | K index... +30.9  LI... -2.6
CAPE... +54.7  CIN... -22.5                | CAPE... +245.6  CIN... -1.2
                                           |
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 -64.6 -84.3  225  41 21   2.4   1.3 | -64.2 -83.6  225  42 22   1.6   0.9
 45000 -60.0 -76.0  225  55 29   4.7   2.6 | -60.3 -76.5  225  60 31   4.8   2.6
 40000 -51.9 -61.4  230  65 33   7.9   4.3 | -52.0 -61.6  230  66 34   8.3   4.5
 38000 -47.2 -53.0  230  63 33   7.9   4.3 | -47.0 -52.6  235  64 33   8.2   4.5
 36000 -42.5 -44.5  235  61 32   7.8   4.3 | -42.1 -43.8  240  62 32   8.0   4.4
 34000 -37.9 -36.2  235  56 29   7.7   4.2 | -37.7 -35.9  240  57 29   7.3   4.0
 32000 -33.3 -27.9  235  50 26   7.5   4.1 | -33.3 -27.9  240  51 26   7.1   3.9
 30000 -28.6 -19.5  235  48 24   7.8   4.3 | -28.7 -19.7  235  46 24   8.0   4.4
 29000 -26.3 -15.3  230  46 24   7.8   4.3 | -26.3 -15.3  235  44 23   8.0   4.4
 28000 -24.0 -11.2  230  45 23   7.3   4.0 | -23.9 -11.0  230  42 22   7.4   4.1
 27000 -21.5  -6.7  230  43 22   6.8   3.7 | -21.4  -6.5  230  41 21   6.8   3.7
 26000 -19.5  -3.1  230  41 21   6.8   3.7 | -19.4  -2.9  230  40 21   6.8   3.8
 25000 -17.5   0.5  225  39 20   6.6   3.6 | -17.4   0.7  230  39 20   6.5   3.6
 24000 -15.7   3.7  230  36 18   6.1   3.3 | -15.7   3.7  230  34 17   5.8   3.2
 23000 -13.8   7.2  230  32 17   6.1   3.3 | -14.1   6.6  230  28 14   5.8   3.2
 22000 -12.0  10.4  235  29 15   5.7   3.1 | -12.4   9.7  230  22 11   5.9   3.3
 21000 -10.5  13.1  240  28 14   5.0   2.7 | -10.6  12.9  230  20 10   6.2   3.4
 20000  -9.1  15.6  245  27 14   5.0   2.8 |  -8.8  16.2  235  18  9   6.2   3.4
 19500  -8.4  16.9  245  27 14   4.8   2.6 |  -7.9  17.8  235  17  9   6.2   3.4
 19000  -7.5  18.5  250  26 13   7.8   4.3 |  -7.0  19.4  235  16  8   6.0   3.3
 18500  -6.4  20.5  250  25 13   7.6   4.2 |  -6.2  20.8  240  16  8   6.0   3.3
 18000  -5.3  22.5  250  24 12   7.3   4.0 |  -5.3  22.5  240  15  8   6.3   3.5
 17500  -4.3  24.3  255  23 12   6.9   3.8 |  -4.3  24.3  235  15  8   6.8   3.7
 17000  -3.3  26.1  255  21 11   6.9   3.8 |  -3.3  26.1  235  15  8   6.8   3.7
 16500  -2.3  27.9  260  20 10   7.2   4.0 |  -2.3  27.9  230  15  8   6.5   3.6
 16000  -1.2  29.8  260  18  9   7.2   4.0 |  -1.4  29.5  225  15  8   6.5   3.6
 15500  -0.2  31.6  260  17  9   7.1   3.9 |  -0.4  31.3  220  14  7   6.8   3.7
 15000   0.8  33.4  260  15  8   7.0   3.9 |   0.5  32.9  210  13  7   6.9   3.8
 14500   1.8  35.2  260  14  7   7.2   4.0 |   1.5  34.7  200  12  6   7.0   3.9
 14000   3.5  38.3  260  13  7   7.8   4.3 |   3.0  37.4  185  10  5   7.4   4.0
 13500   4.6  40.3  255  12  6   8.1   4.5 |   4.1  39.4  170   9  5   8.7   4.8
 13000   5.8  42.4  245  12  6   8.3   4.5 |   5.4  41.7  170   8  4   9.4   5.2
 12500   7.0  44.6  240  12  6   8.3   4.5 |   6.8  44.2  160   8  4   9.5   5.2
 12000   8.2  46.8  225  10  5   8.2   4.5 |   8.2  46.8  160   8  4   9.6   5.3
 11500   9.5  49.1  215   9  5   8.1   4.5 |   9.6  49.3  160   7  4   9.7   5.3
 11000  10.6  51.1  205   8  4   7.8   4.3 |  11.1  52.0  160   7  4   9.8   5.4
 10500  11.7  53.1  190   7  4   5.0   2.8 |  12.6  54.7  160   7  4   5.4   3.0
 10250  12.0  53.6  190   7  4   6.5   3.6 |  12.8  55.0  160   7  4   6.4   3.5
 10000  12.7  54.9  185   7  3  11.4   6.2 |  13.7  56.7  160   7  3  12.9   7.1
  9750  13.5  56.3  180   6  3  10.5   5.8 |  14.5  58.1  160   6  3  11.6   6.3
  9500  14.2  57.6  175   6  3   9.3   5.1 |  15.4  59.7  160   6  3  10.3   5.7
  9250  14.8  58.6  170   6  3   8.3   4.5 |  16.1  61.0  160   6  3   8.9   4.9
  9000  15.4  59.7  170   6  3  10.3   5.6 |  16.8  62.2  160   6  3  10.4   5.7
  8750  16.2  61.2  170   6  3  11.0   6.0 |  17.6  63.7  160   6  3  10.8   5.9
  8500  17.0  62.6  165   5  3  10.3   5.6 |  18.4  65.1  160   5  3  10.4   5.7
  8250  17.7  63.9  170   5  3   9.6   5.3 |  19.1  66.4  160   5  3  10.1   5.5
  8000  18.4  65.1  170   5  3   9.9   5.4 |  19.8  67.6  160   5  3   9.7   5.3
  7750  19.2  66.6  170   5  3  10.0   5.5 |  20.5  68.9  160   5  2   9.2   5.0
  7500  19.9  67.8  165   5  3  10.2   5.6 |  21.2  70.2  160   4  2   9.8   5.4
  7250  20.7  69.3  165   5  3  10.7   5.9 |  22.0  71.6  160   4  2  10.4   5.7
  7000  21.5  70.7  170   5  2   9.9   5.4 |  22.7  72.9  160   4  2   9.6   5.3
  6750  22.2  72.0  165   5  2   9.1   5.0 |  23.4  74.1  160   4  2   8.9   4.9
  6500  22.9  73.2  165   4  2  10.4   5.7 |  24.1  75.4  165   3  2   9.8   5.4
  6250  23.7  74.7  165   4  2  11.8   6.5 |  24.9  76.8  165   3  2  10.6   5.8
  6000  24.6  76.3  165   4  2   9.2   5.1 |  25.7  78.3  160   3  1  10.0   5.5
  5750  25.3  77.5  170   4  2  13.8   7.6 |  26.4  79.5  165   3  1  11.6   6.4
  5500  26.8  80.2  165   4  2  28.7  15.8 |  27.4  81.3  160   2  1  15.6   8.6
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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