Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301239
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0639 MDT Saturday, August 30, 2014

This forecast is for Saturday, August 30, 2014:

If the trigger temperature of 77.7 F/25.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1154 ft/min (5.9 m/s)
   Maximum height of thermals.................. 17698 ft MSL (12413 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1800 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13444 ft MSL (8159 ft AGL)
Thermal soaring outlook for Sunday 08/31....... Excellent

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....................... 18300 ft MSL (13015 ft AGL)
Wave soaring outlook for Sunday 08/31.......... Poor

Remarks... None

Sunrise/Sunset.................... 06:25:38 / 19:35:08 MDT
Total possible sunshine........... 13 hr 9 min 30 sec (789 min 30 sec)
Altitude of sun at 12:59:57 MDT... 59.05 degrees

Upper air data from rawinsonde observation taken on 08/30/2014 at 0600 MDT

Freezing level.................. 14733 ft MSL (9448 ft AGL)
Convective condensation level... 15911 ft MSL (10626 ft AGL)
Lifted condensation level....... 16360 ft MSL (11074 ft AGL)
Lifted index.................... -1.8
K index......................... +14.8

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -60.4 -76.7   295   30   15   5.5   3.0   93.6 200.6    36.9      M    M
 45000  -59.3 -74.7   305   49   25  -0.5  -0.3   70.9 159.7    25.5      M    M
 40000  -53.4 -64.1   315   48   25   4.7   2.6   56.3 133.4    17.6      M    M
 38000  -50.8 -59.4   315   45   23   1.3   0.7   51.5 124.8    14.8      M    M
 36000  -48.0 -54.4   300   36   19   4.1   2.2   47.3 117.1    12.1      M    M
 34000  -44.4 -47.9   305   29   15   7.7   4.2   44.1 111.3    10.2      M    M
 32000  -39.9 -39.8   305   26   13   7.1   3.9   42.3 108.1     9.1      M    M
 30000  -35.1 -31.2   300   24   12   8.5   4.6   40.9 105.7     8.3      M    M
 29000  -32.3 -26.1   305   25   13   9.4   5.2   40.7 105.2     8.2      M    M
 28000  -29.5 -21.1   305   26   13   9.2   5.0   40.5 105.0     8.2      M    M
 27000  -26.3 -15.3   310   26   14   8.2   4.5   40.1 104.2     7.9      M    M
 26000  -23.9 -11.0   300   22   11   8.3   4.5   39.4 102.9     7.5      M    M
 25000  -22.2  -8.0   290   18    9   8.1   4.4   37.9 100.2     6.3      M    M
 24000  -19.8  -3.6   285   18    9   7.4   4.1   37.3  99.1     5.9      M    M
 23000  -18.4  -1.1   290   14    7   4.0   2.2   35.4  95.8     4.4      M    M
 22000  -16.6   2.1   300   10    5   4.8   2.6   34.2  93.5     3.4      M    M
 21000  -15.0   5.0   320   13    7   7.5   4.1   32.7  90.8     2.1      M    M
 20000  -12.8   9.0   285   20   10   7.4   4.1   31.9  89.3     1.4      M    M
 19500  -11.6  11.1   290   19   10   8.4   4.6   31.5  88.7     1.1      M    M
 19000  -10.4  13.3   295   18    9   7.9   4.3   31.2  88.2     0.8      M    M
 18500   -9.3  15.3   295   20   10   7.8   4.3   30.9  87.6     0.5      M    M
 18000   -8.1  17.4   295   22   11   7.8   4.3   30.6  87.0     0.2      M    M
 17500   -6.9  19.6   295   19   10   8.3   4.6   30.3  86.5    -0.1   1139  5.8
 17000   -5.7  21.7   295   16    8   8.3   4.6   30.0  86.1    -0.2   1086  5.5
 16500   -4.4  24.1   295   15    7   8.3   4.6   29.8  85.6    -0.4   1034  5.3
 16000   -3.2  26.2   290   14    7   8.3   4.6   29.5  85.2    -0.7    982  5.0
 15500   -2.0  28.4   290   12    6   8.3   4.6   29.3  84.7    -0.9    931  4.7
 15000   -0.8  30.6   285   10    5   7.4   4.1   29.0  84.2    -1.2    880  4.5
 14500    0.2  32.4   285    8    4   7.0   3.9   28.5  83.4    -1.7    835  4.2
 14000    1.7  35.1   280    6    3   6.5   3.6   27.9  82.2    -2.4    769  3.9
 13500    2.5  36.5   280    5    3   8.1   4.5   27.3  81.2    -3.1    730  3.7
 13000    3.9  39.0   280    5    3   9.1   5.0   27.2  81.0    -3.2    675  3.4
 12500    5.2  41.4   275    4    2   9.2   5.0   27.2  80.9    -3.3    621  3.2
 12000    6.5  43.7   275    4    2   9.2   5.0   27.1  80.7    -3.5    566  2.9
 11500    7.9  46.2   275    5    3   9.2   5.0   26.9  80.5    -3.6    511  2.6
 11000    9.2  48.6   270    6    3   9.2   5.0   26.8  80.3    -3.8    456  2.3
 10500   10.5  50.9   270    7    4   9.0   4.9   26.8  80.2    -3.9    402  2.0
 10250   11.2  52.2   275    8    4   8.5   4.7   26.7  80.0    -4.0    375  1.9
 10000   11.8  53.2   275    8    4   8.4   4.6   26.6  79.9    -4.1    349  1.8
  9750   12.4  54.3   280    9    5   8.4   4.6   26.5  79.7    -4.2    323  1.6
  9500   13.0  55.4   280   10    5   8.4   4.6   26.4  79.5    -4.4    297  1.5
  9250   13.6  56.5   285   11    6   8.4   4.6   26.3  79.4    -4.5    271  1.4
  9000   14.3  57.7   285   12    6   8.4   4.6   26.2  79.2    -4.6    245  1.2
  8750   14.9  58.8   280   11    5   8.4   4.6   26.1  79.0    -4.7    219  1.1
  8500   15.5  59.9   280    9    5   8.4   4.6   26.0  78.8    -4.8    193  1.0
  8250   16.1  61.0   275    8    4   8.5   4.6   25.9  78.7    -4.9    167  0.8
  8000   16.8  62.2   270    7    4   8.4   4.6   25.8  78.5    -5.0    141  0.7
  7750   17.4  63.3   270    8    4   8.5   4.7   25.7  78.3    -5.2    115  0.6
  7500   18.0  64.4   265    8    4   8.4   4.6   25.6  78.1    -5.3     89  0.5
  7250   18.6  65.5   265    8    4   8.8   4.8   25.5  77.9    -5.4     63  0.3
  7000   19.2  66.6   265    9    5   7.1   3.9   25.4  77.8    -5.5     37  0.2
  6750   19.2  66.6   245    9    5  -9.2  -5.1   24.7  76.5    -6.3     30  0.2
  6500   18.1  64.6   230   10    5 -12.0  -6.6   22.9  73.2    -8.1     56  0.3
  6250   17.8  64.0   220   12    6  -1.3  -0.7   21.8  71.2    -9.2     60  0.3
  6000   17.7  63.9   210   14    7   0.9   0.5   21.0  69.8   -10.1     54  0.3
  5750   17.6  63.7   210   10    5  -6.8  -3.7   20.2  68.4   -10.9     49  0.2
  5500   16.0  60.8   210    5    2 -36.4 -20.0   18.0  64.3   -13.2     90  0.5

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

           08/30/2014 at 0900 MDT          |       08/30/2014 at 1200 MDT
                                           |
K index... +17.9  LI... -0.9               | K index... +16.8  LI... -1.9
CAPE... +48.6  CIN... -73.9                | CAPE... +254.3  CIN... -20.4
                                           |
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 -62.8 -81.0  305  27 14   1.0   0.6 | -63.8 -82.8  290  29 15   1.1   0.6
 45000 -59.9 -75.8  315  39 20   4.8   2.7 | -60.5 -76.9  300  38 19   5.7   3.1
 40000 -52.3 -62.1  315  41 21   5.2   2.9 | -51.7 -61.1  305  43 22   4.5   2.5
 38000 -49.2 -56.6  315  40 21   5.2   2.9 | -49.0 -56.2  310  43 22   4.5   2.5
 36000 -46.1 -51.0  315  39 20   5.2   2.9 | -46.3 -51.3  310  44 23   4.5   2.5
 34000 -42.5 -44.5  310  36 19   6.1   3.3 | -42.3 -44.1  310  42 22   7.4   4.0
 32000 -38.9 -38.0  310  34 17   6.1   3.4 | -37.9 -36.2  310  39 20   7.4   4.0
 30000 -34.5 -30.1  305  30 15   7.9   4.3 | -33.4 -28.1  305  33 17   7.5   4.1
 29000 -32.2 -26.0  305  28 14   7.9   4.3 | -31.2 -24.2  305  29 15   7.5   4.1
 28000 -29.9 -21.8  300  26 13   7.9   4.3 | -28.3 -18.9  300  24 12   7.6   4.2
 27000 -26.9 -16.4  295  23 12   8.1   4.4 | -26.1 -15.0  295  23 12   7.7   4.2
 26000 -24.4 -11.9  295  20 10   8.1   4.4 | -23.8 -10.8  295  21 11   7.7   4.2
 25000 -22.0  -7.6  290  18  9   8.2   4.5 | -21.5  -6.7  295  20 10   7.8   4.3
 24000 -19.9  -3.8  290  17  9   7.1   3.9 | -19.5  -3.1  300  21 11   6.5   3.6
 23000 -17.8  -0.0  290  17  9   7.2   3.9 | -17.6   0.3  305  22 11   6.6   3.6
 22000 -15.7   3.7  290  18  9   7.1   3.9 | -15.7   3.7  310  24 12   6.7   3.7
 21000 -13.8   7.2  295  18  9   6.2   3.4 | -13.6   7.5  310  23 12   7.2   3.9
 20000 -12.0  10.4  295  19 10   6.2   3.4 | -11.5  11.3  310  23 12   7.2   3.9
 19500 -11.1  12.0  295  19 10   6.1   3.4 | -10.4  13.3  310  22 11   7.2   4.0
 19000 -10.1  13.8  295  19 10   7.1   3.9 |  -9.3  15.3  305  21 11   6.8   3.8
 18500  -9.0  15.8  295  18  9   7.3   4.0 |  -8.3  17.1  305  20 10   6.8   3.8
 18000  -7.8  18.0  295  17  9   7.4   4.1 |  -7.3  18.9  300  19 10   7.1   3.9
 17500  -6.7  19.9  295  16  8   7.7   4.2 |  -6.2  20.8  295  18  9   8.0   4.4
 17000  -5.6  21.9  295  15  8   7.7   4.2 |  -5.0  23.0  295  17  9   7.9   4.3
 16500  -4.5  23.9  290  14  7   8.0   4.4 |  -3.8  25.2  290  16  8   8.2   4.5
 16000  -3.3  26.1  290  13  7   8.0   4.4 |  -2.6  27.3  285  15  8   8.3   4.5
 15500  -2.1  28.2  290  12  6   8.3   4.5 |  -1.4  29.5  285  15  8   8.5   4.7
 15000  -0.9  30.4  285  11  6   8.5   4.7 |  -0.2  31.6  280  14  7   8.7   4.8
 14500   0.3  32.5  285  11  5   8.7   4.7 |   1.1  34.0  280  14  7   8.8   4.8
 14000   2.3  36.1  280  10  5   9.1   5.0 |   3.1  37.6  280  13  7   8.8   4.8
 13500   3.6  38.5  280  10  5   9.2   5.0 |   4.4  39.9  275  13  7   8.9   4.9
 13000   5.0  41.0  275   9  5   9.3   5.1 |   5.7  42.3  275  12  6   9.0   4.9
 12500   6.3  43.3  275   9  5   9.3   5.1 |   7.0  44.6  270  12  6   9.0   4.9
 12000   7.7  45.9  270   9  5   9.2   5.0 |   8.3  46.9  270  11  6   9.0   4.9
 11500   9.0  48.2  270   9  5   9.0   4.9 |   9.7  49.5  265  11  5   8.9   4.9
 11000  10.3  50.5  265   9  5   8.2   4.5 |  11.0  51.8  260  10  5   8.5   4.7
 10500  11.5  52.7  255   9  5   4.3   2.4 |  12.3  54.1  255  10  5   5.5   3.0
 10250  11.7  53.1  255   9  5   5.5   3.0 |  12.5  54.5  255  10  5   6.3   3.5
 10000  12.4  54.3  250   9  5  11.5   6.3 |  13.3  55.9  250  10  5  11.0   6.1
  9750  13.1  55.6  245  10  5  10.3   5.7 |  14.0  57.2  250   9  5  10.1   5.5
  9500  13.9  57.0  240  10  5   9.1   5.0 |  14.7  58.5  245   9  5   9.3   5.1
  9250  14.4  57.9  235  10  5   7.1   3.9 |  15.4  59.7  240   9  5   7.9   4.4
  9000  15.0  59.0  235  10  5   8.8   4.9 |  16.0  60.8  240   9  5   8.9   4.9
  8750  15.7  60.3  235  11  5  10.0   5.5 |  16.7  62.1  235   9  5   9.4   5.2
  8500  16.4  61.5  230  11  6   9.2   5.0 |  17.3  63.1  230   9  5   9.1   5.0
  8250  17.0  62.6  230  11  6   8.6   4.7 |  18.0  64.4  230   9  5   9.0   4.9
  8000  17.7  63.9  230  11  6   8.4   4.6 |  18.6  65.5  225   9  5   9.0   5.0
  7750  18.2  64.8  225  11  5   8.2   4.5 |  19.2  66.6  220   9  4   9.1   5.0
  7500  18.8  65.8  225  10  5   7.2   3.9 |  19.7  67.5  215   8  4   9.5   5.2
  7250  19.3  66.7  225  10  5   6.1   3.4 |  20.5  68.9  215   8  4   9.8   5.4
  7000  19.8  67.6  220  10  5   6.8   3.7 |  21.2  70.2  210   8  4   9.9   5.4
  6750  20.2  68.4  220  10  5   4.6   2.5 |  21.9  71.4  210   8  4  10.4   5.7
  6500  20.3  68.5  220  10  5  -1.9  -1.0 |  22.7  72.9  210   8  4  10.6   5.8
  6250  20.0  68.0  220  10  5  -4.3  -2.4 |  23.5  74.3  210   7  4  10.9   6.0
  6000  19.6  67.3  220   9  5  -4.5  -2.4 |  24.3  75.7  210   7  4   9.8   5.4
  5750  19.3  66.7  220  10  5  -3.6  -2.0 |  25.0  77.0  210   7  4  13.0   7.2
  5500  19.0  66.2  215   8  4   1.6   0.9 |  26.3  79.3  210   7  3  22.3  12.2

           08/30/2014 at 1500 MDT          |       08/30/2014 at 1800 MDT
                                           |
K index... +23.7  LI... -0.8               | K index... +30.0  LI... -0.3
CAPE... +43.7  CIN... -38.5                | CAPE... 0.0  CIN... -10.2
                                           |
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 -64.3 -83.7  280  32 16   1.2   0.6 | -63.7 -82.7  285  35 18   1.4   0.8
 45000 -60.8 -77.4  285  38 20   5.5   3.0 | -60.5 -76.9  285  45 23   4.3   2.4
 40000 -52.5 -62.5  285  43 22   5.1   2.8 | -53.5 -64.3  275  52 27   5.8   3.2
 38000 -49.5 -57.1  290  46 24   5.1   2.8 | -50.0 -58.0  280  50 25   5.8   3.2
 36000 -46.4 -51.5  300  51 26   5.2   2.9 | -46.5 -51.7  285  47 24   5.8   3.2
 34000 -41.6 -42.9  295  45 23   7.7   4.2 | -42.0 -43.6  285  39 20   7.9   4.3
 32000 -37.0 -34.6  290  37 19   7.5   4.1 | -37.3 -35.1  275  31 16   7.9   4.3
 30000 -32.3 -26.1  290  33 17   8.0   4.4 | -32.3 -26.1  270  31 16   8.6   4.7
 29000 -29.9 -21.8  285  31 16   8.0   4.4 | -29.8 -21.6  265  33 17   8.6   4.7
 28000 -27.5 -17.5  285  30 15   7.7   4.2 | -27.3 -17.1  265  34 18   8.6   4.7
 27000 -25.4 -13.7  290  28 14   6.8   3.7 | -24.5 -12.1  265  33 17   7.3   4.0
 26000 -23.4 -10.1  290  26 13   6.8   3.8 | -22.4  -8.3  260  32 17   7.3   4.0
 25000 -21.3  -6.3  290  24 12   6.9   3.8 | -20.2  -4.4  260  31 16   7.3   4.0
 24000 -19.3  -2.7  290  22 11   6.9   3.8 | -18.1  -0.6  255  30 15   7.0   3.9
 23000 -17.3   0.9  290  20 10   6.9   3.8 | -16.1   3.0  255  28 14   7.0   3.9
 22000 -15.2   4.6  290  18  9   6.9   3.8 | -14.0   6.8  255  26 14   7.1   3.9
 21000 -13.2   8.2  285  17  9   7.1   3.9 | -12.0  10.4  260  25 13   6.8   3.7
 20000 -11.1  12.0  280  17  9   7.1   3.9 | -10.1  13.8  260  23 12   6.8   3.7
 19500 -10.0  14.0  280  17  9   7.1   3.9 |  -9.1  15.6  260  22 11   6.8   3.8
 19000  -8.9  16.0  275  17  9   7.8   4.3 |  -8.1  17.4  260  21 11   6.8   3.7
 18500  -7.8  18.0  275  17  9   8.0   4.4 |  -7.1  19.2  260  20 10   6.8   3.7
 18000  -6.6  20.1  280  17  9   8.0   4.4 |  -6.2  20.8  260  19 10   6.8   3.7
 17500  -5.4  22.3  280  17  9   7.8   4.3 |  -5.2  22.6  260  18  9   6.8   3.7
 17000  -3.7  25.3  275  17  9   7.8   4.3 |  -4.2  24.4  260  17  9   6.8   3.7
 16500  -2.6  27.3  275  17  9   7.9   4.3 |  -3.2  26.2  260  15  8   6.7   3.7
 16000  -1.4  29.5  275  17  9   7.9   4.3 |  -2.3  27.9  255  14  7   6.6   3.6
 15500  -0.3  31.5  275  17  9   8.0   4.4 |  -1.3  29.7  250  13  7   6.6   3.6
 15000   0.9  33.6  275  16  8   8.0   4.4 |  -0.4  31.3  240  11  6   6.6   3.6
 14500   2.1  35.8  275  15  8   8.9   4.9 |   0.6  33.1  230  10  5   6.7   3.7
 14000   3.5  38.3  275  14  7   9.4   5.2 |   2.5  36.5  225   9  5   8.9   4.9
 13500   4.9  40.8  275  13  6   9.5   5.2 |   3.8  38.8  220   8  4   9.2   5.1
 13000   6.3  43.3  275  11  6   9.6   5.2 |   5.3  41.5  220   8  4   9.6   5.3
 12500   7.8  46.0  280  10  5   9.5   5.2 |   6.7  44.1  220   8  4   9.7   5.3
 12000   9.2  48.6  275   9  4   9.3   5.1 |   8.2  46.8  220   8  4  10.1   5.6
 11500  10.6  51.1  275   7  4   9.2   5.1 |   9.7  49.5  220   8  4  10.0   5.5
 11000  11.9  53.4  265   6  3   7.6   4.2 |  11.0  51.8  220   8  4   8.6   4.7
 10500  13.0  55.4  255   5  3  10.2   5.6 |  12.3  54.1  220   8  4  11.9   6.5
 10250  13.9  57.0  245   4  2  10.8   5.9 |  13.4  56.1  220   8  4  12.8   7.0
 10000  14.5  58.1  235   4  2   7.8   4.3 |  14.1  57.4  220   8  4   9.0   5.0
  9750  15.1  59.2  225   4  2   8.7   4.8 |  14.8  58.6  220   8  4  10.2   5.6
  9500  15.7  60.3  215   4  2   8.3   4.6 |  15.6  60.1  220   8  4   9.4   5.1
  9250  16.3  61.3  210   5  2   8.7   4.8 |  16.2  61.2  220   8  4   9.0   5.0
  9000  17.0  62.6  205   5  2   9.6   5.3 |  17.0  62.6  220   8  4  10.0   5.5
  8750  17.7  63.9  205   5  2  10.0   5.5 |  17.7  63.9  220   8  4  10.4   5.7
  8500  18.4  65.1  205   5  2   9.9   5.4 |  18.5  65.3  220   8  4  10.3   5.6
  8250  19.2  66.6  205   5  2   9.9   5.4 |  19.3  66.7  220   8  4  10.4   5.7
  8000  19.9  67.8  205   5  2   9.8   5.4 |  20.0  68.0  220   7  4   9.7   5.3
  7750  20.6  69.1  205   5  2   9.5   5.2 |  20.7  69.3  220   7  4   8.9   4.9
  7500  21.3  70.3  205   5  2   9.9   5.5 |  21.4  70.5  225   7  4   9.6   5.3
  7250  22.1  71.8  205   5  2  10.7   5.9 |  22.1  71.8  225   7  4  10.8   5.9
  7000  22.9  73.2  205   5  2  10.3   5.7 |  22.9  73.2  225   7  4  10.3   5.7
  6750  23.6  74.5  205   5  2   9.1   5.0 |  23.6  74.5  225   7  3   8.7   4.8
  6500  24.3  75.7  205   5  2  10.0   5.5 |  24.3  75.7  225   7  3   9.5   5.2
  6250  25.1  77.2  205   4  2  11.5   6.3 |  25.1  77.2  230   6  3  10.7   5.9
  6000  26.0  78.8  210   4  2  10.4   5.7 |  25.8  78.4  230   6  3  10.2   5.6
  5750  26.7  80.1  210   4  2  12.0   6.6 |  26.6  79.9  235   6  3   9.2   5.0
  5500  27.8  82.0  210   4  2  19.0  10.4 |  27.2  81.0  235   5  3   8.0   4.4
________________________________________________________________________________

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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