Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 300028
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1828 MDT Friday, August 29, 2014

This forecast is for Saturday, August 30, 2014:

If the trigger temperature of 78.2 F/25.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1127 ft/min (5.7 m/s)
   Maximum height of thermals.................. 17408 ft MSL (12121 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1630 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11260 ft MSL (5973 ft AGL)
Thermal soaring outlook for Sunday 08/31....... 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)................ Weak NVA
Potential height of wave....................... 46194 ft MSL (40907 ft AGL)
Wave soaring outlook for Sunday 08/31.......... Good

Remarks... Moderate westerly flow aloft across the state with afternoon
           instability producing showers after 1500 MDT.

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 numerical model forecast valid on 08/30/2014 at 0600 MDT

Freezing level.................. 14740 ft MSL (9453 ft AGL)
Convective condensation level... 14957 ft MSL (9670 ft AGL)
Lifted condensation level....... 15699 ft MSL (10412 ft AGL)
Lifted index.................... -3.9
K index......................... +22.4

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  -63.3 -81.9   300   31   16   1.0   0.6      M     M       M      M    M
 45000  -60.3 -76.5   310   41   21   4.8   2.6      M     M       M      M    M
 40000  -53.2 -63.8   320   43   22   4.7   2.6      M     M       M      M    M
 38000  -50.4 -58.7   320   41   21   4.7   2.6      M     M       M      M    M
 36000  -47.5 -53.5   325   39   20   4.7   2.6      M     M       M      M    M
 34000  -43.6 -46.5   320   35   18   7.5   4.1      M     M       M      M    M
 32000  -38.5 -37.3   310   28   15   7.5   4.1      M     M       M      M    M
 30000  -34.1 -29.4   305   24   13   7.5   4.1   41.4 106.5     8.6      M    M
 29000  -31.8 -25.2   305   23   12   7.5   4.1   40.5 104.9     8.1      M    M
 28000  -29.6 -21.3   300   21   11   7.6   4.2   39.8 103.6     7.6      M    M
 27000  -27.3 -17.1   300   20   10   7.7   4.2   38.9 102.0     7.0      M    M
 26000  -25.0 -13.0   300   19   10   7.7   4.2   38.1 100.6     6.4      M    M
 25000  -22.7  -8.9   300   18    9   7.8   4.3   37.5  99.4     5.9      M    M
 24000  -20.6  -5.1   295   18    9   6.6   3.6   36.4  97.5     5.1      M    M
 23000  -18.6  -1.5   295   17    9   6.6   3.6   35.2  95.4     4.2      M    M
 22000  -16.6   2.1   290   17    9   6.5   3.6   34.2  93.5     3.4      M    M
 21000  -14.4   6.1   290   17    9   7.6   4.1   33.3  91.9     2.6      M    M
 20000  -12.2  10.0   290   17    9   7.6   4.1   32.5  90.5     2.0      M    M
 19500  -11.0  12.2   295   17    9   7.6   4.1   32.1  89.9     1.7      M    M
 19000   -9.9  14.2   295   17    9   7.5   4.1   31.8  89.2     1.4      M    M
 18500   -8.8  16.2   295   16    8   7.4   4.1   31.4  88.5     1.0      M    M
 18000   -7.7  18.1   300   14    7   7.4   4.0   31.0  87.8     0.7      M    M
 17500   -6.7  19.9   305   13    6   6.6   3.6   30.5  86.9     0.2      M    M
 17000   -5.7  21.7   310   11    6   6.7   3.7   30.0  85.9    -0.3   1101  5.6
 16500   -4.7  23.5   315   10    5   7.8   4.3   29.5  85.1    -0.8   1056  5.4
 16000   -3.0  26.6   320    9    4   8.0   4.4   29.1  84.3    -1.2    982  5.0
 15500   -1.8  28.8   320    8    4   9.2   5.0   28.9  84.0    -1.5    930  4.7
 15000   -0.4  31.3   320    7    4   9.2   5.1   28.8  83.8    -1.6    875  4.4
 14500    0.9  33.6   320    7    4   8.8   4.8   28.7  83.6    -1.8    821  4.2
 14000    2.1  35.8   310    7    4   8.6   4.7   28.5  83.2    -2.0    769  3.9
 13500    3.4  38.1   305    7    4   8.7   4.8   28.3  82.9    -2.2    717  3.6
 13000    4.7  40.5   300    7    4   8.9   4.9   28.1  82.6    -2.4    663  3.4
 12500    6.0  42.8   295    8    4   8.9   4.9   28.0  82.4    -2.6    610  3.1
 12000    7.3  45.1   290    8    4   9.0   4.9   27.9  82.2    -2.8    555  2.8
 11500    8.6  47.5   285    9    4   8.9   4.9   27.8  82.0    -2.9    501  2.5
 11000    9.8  49.6   285    9    4   8.2   4.5   27.6  81.6    -3.1    449  2.3
 10500   11.1  52.0   280    9    4   5.2   2.8   27.4  81.3    -3.4    397  2.0
 10250   11.3  52.3   280    9    4   5.9   3.2   26.9  80.4    -3.9    382  1.9
 10000   12.0  53.6   275    8    4  10.5   5.8   26.9  80.4    -3.9    354  1.8
  9750   12.7  54.9   265    8    4   9.6   5.2   26.9  80.3    -4.0    325  1.7
  9500   13.4  56.1   260    8    4   8.9   4.9   26.9  80.3    -4.0    297  1.5
  9250   14.0  57.2   255    8    4   6.8   3.7   26.7  80.0    -4.2    273  1.4
  9000   14.5  58.1   250    8    4   8.1   4.4   26.5  79.7    -4.4    250  1.3
  8750   15.2  59.4   245    8    4   9.6   5.3   26.4  79.6    -4.5    223  1.1
  8500   15.8  60.4   240    8    4   8.6   4.7   26.4  79.5    -4.6    195  1.0
  8250   16.4  61.5   240    8    4   7.8   4.3   26.3  79.3    -4.7    170  0.9
  8000   17.0  62.6   235    8    4   7.6   4.1   26.1  79.0    -4.9    145  0.7
  7750   17.6  63.7   235    8    4   8.0   4.4   26.0  78.7    -5.0    121  0.6
  7500   18.1  64.6   230    8    4   6.4   3.5   25.8  78.4    -5.2     96  0.5
  7250   18.5  65.3   230    8    4   4.6   2.5   25.4  77.8    -5.6     78  0.4
  7000   18.8  65.8   230    8    4   5.8   3.2   25.1  77.1    -6.0     60  0.3
  6750   19.2  66.6   225    8    4   4.2   2.3   24.8  76.6    -6.3     41  0.2
  6500   19.2  66.6   225    8    4  -5.1  -2.8   24.0  75.3    -7.1     35  0.2
  6250   18.4  65.1   225    8    4 -11.9  -6.6   22.6  72.6    -8.6     51  0.3
  6000   17.7  63.9   225    8    4  -4.8  -2.6   21.1  70.0   -10.2     66  0.3
  5750   17.3  63.1   235    8    4 -12.4  -6.8   20.0  68.0   -11.3     71  0.4
  5500   15.1  59.2   225    7    4 -43.0 -23.6   17.2  63.0   -14.2    130  0.7

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

           08/30/2014 at 0900 MDT          |       08/30/2014 at 1200 MDT
                                           |
K index... +18.3  LI... -0.6               | K index... +12.9  LI... -1.4
CAPE... +20.2  CIN... -96.3                | CAPE... +72.7  CIN... -40.1
                                           |
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 -63.5 -82.3  305  27 14   0.4   0.2 | -63.8 -82.8  285  25 13   0.6   0.3
 45000 -61.1 -78.0  315  38 20   5.3   2.9 | -61.1 -78.0  300  34 17   5.5   3.0
 40000 -53.1 -63.6  315  40 21   4.9   2.7 | -52.6 -62.7  305  40 20   4.9   2.7
 38000 -50.2 -58.4  315  42 22   4.9   2.7 | -49.7 -57.5  305  39 20   4.9   2.7
 36000 -47.2 -53.0  315  44 23   5.0   2.7 | -46.8 -52.2  310  39 20   4.8   2.6
 34000 -42.4 -44.3  315  42 22   7.9   4.3 | -42.2 -44.0  310  37 19   8.4   4.6
 32000 -37.7 -35.9  315  39 20   7.8   4.3 | -37.1 -34.8  305  36 18   8.4   4.6
 30000 -33.1 -27.6  315  35 18   7.6   4.1 | -32.5 -26.5  300  32 16   7.6   4.2
 29000 -30.8 -23.4  315  33 17   7.6   4.1 | -30.2 -22.4  300  29 15   7.6   4.2
 28000 -28.6 -19.5  315  31 16   7.7   4.2 | -27.9 -18.2  295  27 14   7.6   4.2
 27000 -26.2 -15.2  315  29 15   8.0   4.4 | -25.4 -13.7  295  26 13   6.8   3.7
 26000 -23.8 -10.8  310  28 14   8.0   4.4 | -23.4 -10.1  300  26 13   6.8   3.7
 25000 -21.4  -6.5  310  26 14   8.2   4.5 | -21.4  -6.5  300  25 13   6.9   3.8
 24000 -19.4  -2.9  305  24 12   5.7   3.2 | -19.2  -2.6  305  25 13   7.7   4.2
 23000 -17.8  -0.0  300  21 11   5.8   3.2 | -16.9   1.6  305  26 13   7.7   4.2
 22000 -16.1   3.0  290  18  9   5.9   3.2 | -14.7   5.5  310  27 14   7.4   4.1
 21000 -14.2   6.4  290  16  8   6.5   3.6 | -12.9   8.8  300  24 12   5.6   3.1
 20000 -12.2  10.0  285  16  8   6.5   3.6 | -11.2  11.8  290  22 11   5.6   3.1
 19500 -11.3  11.7  285  15  8   6.5   3.6 | -10.3  13.5  285  21 11   5.5   3.0
 19000 -10.3  13.5  285  15  8   7.6   4.2 |  -9.3  15.3  280  20 10   7.5   4.1
 18500  -9.1  15.6  285  15  7   8.0   4.4 |  -8.2  17.2  275  19 10   7.6   4.2
 18000  -7.8  18.0  285  14  7   8.0   4.4 |  -7.1  19.2  265  19 10   7.6   4.2
 17500  -6.7  19.9  285  13  7   7.7   4.2 |  -6.0  21.2  265  18  9   7.4   4.1
 17000  -5.6  21.9  285  13  6   7.7   4.2 |  -4.9  23.2  265  17  9   7.4   4.0
 16500  -3.9  25.0  285  11  6   7.7   4.2 |  -3.8  25.2  265  17  9   8.3   4.6
 16000  -2.8  27.0  280  10  5   7.6   4.2 |  -2.5  27.5  265  16  8   8.4   4.6
 15500  -1.6  29.1  280   9  4   8.9   4.9 |  -1.3  29.7  265  14  7   8.4   4.6
 15000  -0.3  31.5  280   8  4   8.9   4.9 |  -0.1  31.8  265  13  7   8.4   4.6
 14500   1.0  33.8  280   7  4   9.0   4.9 |   1.2  34.2  265  12  6   8.4   4.6
 14000   2.3  36.1  280   7  4   9.0   4.9 |   3.1  37.6  265  11  6   8.5   4.7
 13500   3.7  38.7  285   7  3   9.0   4.9 |   4.3  39.7  265  10  5   8.6   4.7
 13000   5.0  41.0  285   7  3   8.9   4.9 |   5.6  42.1  265  10  5   8.7   4.8
 12500   6.3  43.3  285   7  3   8.9   4.9 |   6.9  44.4  265  10  5   8.9   4.9
 12000   7.6  45.7  285   7  3   8.9   4.9 |   8.3  46.9  265   9  5   9.2   5.1
 11500   8.9  48.0  285   7  3   8.9   4.9 |   9.6  49.3  260   9  5   9.1   5.0
 11000  10.2  50.4  280   7  3   8.4   4.6 |  10.9  51.6  255   8  4   8.5   4.7
 10500  11.5  52.7  275   6  3   4.5   2.5 |  12.2  54.0  255   8  4   4.7   2.6
 10250  11.7  53.1  275   6  3   5.7   3.1 |  12.4  54.3  250   8  4   5.7   3.1
 10000  12.4  54.3  270   6  3  11.8   6.5 |  13.2  55.8  250   7  4  11.5   6.3
  9750  13.2  55.8  265   6  3  10.5   5.8 |  13.9  57.0  245   7  4  10.2   5.6
  9500  14.0  57.2  265   6  3   9.6   5.3 |  14.7  58.5  240   7  4   9.5   5.2
  9250  14.6  58.3  260   6  3   7.0   3.8 |  15.3  59.5  235   7  3   8.0   4.4
  9000  15.1  59.2  255   6  3   8.0   4.4 |  15.9  60.6  235   7  3   9.1   5.0
  8750  15.7  60.3  255   6  3   9.4   5.2 |  16.6  61.9  230   6  3   9.8   5.4
  8500  16.4  61.5  250   6  3   8.6   4.7 |  17.3  63.1  225   6  3   9.1   5.0
  8250  17.0  62.6  245   6  3   8.1   4.5 |  18.0  64.4  220   6  3   8.5   4.7
  8000  17.6  63.7  245   6  3   7.6   4.2 |  18.6  65.5  215   6  3   8.1   4.5
  7750  18.1  64.6  240   5  3   7.5   4.1 |  19.1  66.4  215   6  3   7.5   4.1
  7500  18.6  65.5  240   5  3   6.3   3.5 |  19.6  67.3  210   6  3   8.7   4.8
  7250  19.0  66.2  240   5  3   5.1   2.8 |  20.3  68.5  205   5  3   9.9   5.5
  7000  19.4  66.9  240   5  3   5.5   3.0 |  20.9  69.6  200   5  3   9.4   5.2
  6750  19.7  67.5  240   5  3   3.5   1.9 |  21.5  70.7  200   5  2   9.2   5.0
  6500  19.7  67.5  240   5  3  -2.2  -1.2 |  22.2  72.0  200   5  2  10.4   5.7
  6250  19.4  66.9  235   5  3  -4.3  -2.4 |  23.0  73.4  200   4  2  12.0   6.6
  6000  19.0  66.2  235   6  3  -4.9  -2.7 |  23.8  74.8  200   4  2   9.8   5.4
  5750  18.7  65.7  235   6  3  -2.3  -1.2 |  24.6  76.3  200   4  2  12.1   6.6
  5500  18.7  65.7  225   6  3   7.0   3.9 |  25.8  78.4  200   4  2  22.8  12.5

           08/30/2014 at 1500 MDT          |       08/30/2014 at 1800 MDT
                                           |
K index... +24.5  LI... 0.0                | K index... +28.7  LI... -1.0
CAPE... 0.0  CIN... -10.5                  | CAPE... +56.5  CIN... -20.6
                                           |
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 -64.3 -83.7  275  29 15   0.9   0.5 | -64.0 -83.2  275  31 16   0.9   0.5
 45000 -61.2 -78.2  280  35 18   5.3   2.9 | -61.1 -78.0  280  41 21   4.9   2.7
 40000 -53.3 -63.9  280  39 20   5.5   3.0 | -53.7 -64.7  280  48 24   5.8   3.2
 38000 -50.0 -58.0  285  39 20   5.4   3.0 | -50.2 -58.4  280  45 23   5.8   3.2
 36000 -46.7 -52.1  295  39 20   5.5   3.0 | -46.8 -52.2  285  43 22   5.8   3.2
 34000 -41.6 -42.9  290  37 19   8.2   4.5 | -41.6 -42.9  280  42 21   8.3   4.5
 32000 -36.7 -34.1  280  34 17   8.1   4.4 | -36.6 -33.9  280  41 21   8.1   4.5
 30000 -31.7 -25.1  280  35 18   8.4   4.6 | -31.7 -25.1  275  39 20   8.2   4.5
 29000 -29.2 -20.6  280  36 18   8.4   4.6 | -29.2 -20.6  275  37 19   8.2   4.5
 28000 -26.7 -16.1  280  37 19   7.8   4.3 | -26.8 -16.2  275  36 18   7.8   4.3
 27000 -24.6 -12.3  280  35 18   7.1   3.9 | -24.6 -12.3  275  34 18   7.2   3.9
 26000 -22.5  -8.5  280  33 17   7.1   3.9 | -22.5  -8.5  275  33 17   7.2   3.9
 25000 -20.4  -4.7  275  31 16   7.2   4.0 | -20.4  -4.7  275  32 16   7.3   4.0
 24000 -18.5  -1.3  280  28 14   6.3   3.4 | -18.4  -1.1  275  31 16   6.5   3.5
 23000 -16.7   1.9  280  25 13   6.3   3.5 | -16.5   2.3  270  29 15   6.5   3.6
 22000 -14.8   5.4  285  22 12   6.3   3.4 | -14.6   5.7  270  28 14   6.4   3.5
 21000 -12.8   9.0  285  23 12   7.2   4.0 | -12.6   9.3  270  28 15   7.3   4.0
 20000 -10.6  12.9  280  25 13   7.3   4.0 | -10.4  13.3  265  29 15   7.3   4.0
 19500  -9.6  14.7  280  26 13   7.3   4.0 |  -9.4  15.1  265  30 15   7.3   4.0
 19000  -8.5  16.7  280  27 14   7.1   3.9 |  -8.3  17.1  260  30 15   7.2   3.9
 18500  -7.5  18.5  275  26 14   7.0   3.9 |  -7.3  18.9  260  28 14   7.1   3.9
 18000  -6.5  20.3  275  26 13   7.1   3.9 |  -6.3  20.7  260  26 13   7.2   3.9
 17500  -5.4  22.3  275  25 13   7.3   4.0 |  -5.2  22.6  260  24 13   7.9   4.3
 17000  -3.8  25.2  275  23 12   7.3   4.0 |  -3.5  25.7  255  22 11   7.9   4.3
 16500  -2.8  27.0  275  22 11   7.2   4.0 |  -2.2  28.0  255  20 11   8.7   4.8
 16000  -1.7  28.9  275  21 11   7.2   3.9 |  -1.0  30.2  255  19 10   8.6   4.7
 15500  -0.6  30.9  275  19 10   8.3   4.5 |   0.3  32.5  255  17  9   8.9   4.9
 15000   0.7  33.3  270  18  9   8.3   4.6 |   1.6  34.9  255  16  8   8.9   4.9
 14500   1.9  35.4  270  16  8   8.8   4.8 |   3.0  37.4  255  15  8   9.1   5.0
 14000   3.3  37.9  270  14  7   9.1   5.0 |   4.4  39.9  250  14  7   9.2   5.0
 13500   4.6  40.3  265  13  7   9.3   5.1 |   5.7  42.3  250  13  7   9.1   5.0
 13000   6.0  42.8  265  11  6   9.6   5.2 |   7.1  44.8  250  12  6   9.0   4.9
 12500   7.5  45.5  260  10  5   9.5   5.2 |   8.4  47.1  245  11  6   9.0   4.9
 12000   8.9  48.0  255   8  4   9.0   4.9 |   9.7  49.5  240  10  5   8.8   4.8
 11500  10.3  50.5  245   7  4   8.9   4.9 |  11.0  51.8  235   9  5   8.8   4.8
 11000  11.5  52.7  235   6  3   7.8   4.3 |  12.2  54.0  230   8  4   7.8   4.3
 10500  12.7  54.9  230   6  3  10.3   5.7 |  13.4  56.1  220   8  4  10.9   6.0
 10250  13.6  56.5  225   6  3  11.0   6.0 |  14.4  57.9  220   8  4  11.8   6.5
 10000  14.3  57.7  220   6  3   8.1   4.4 |  15.0  59.0  215   7  4   8.2   4.5
  9750  14.9  58.8  215   6  3   8.9   4.9 |  15.7  60.3  215   7  4   9.2   5.1
  9500  15.6  60.1  210   6  3   8.6   4.7 |  16.4  61.5  210   7  3   8.8   4.8
  9250  16.2  61.2  205   6  3   8.9   4.9 |  17.0  62.6  205   6  3   8.5   4.7
  9000  16.8  62.2  205   6  3   9.5   5.2 |  17.7  63.9  205   6  3   8.8   4.9
  8750  17.5  63.5  205   6  3   9.6   5.3 |  18.4  65.1  205   6  3   9.2   5.1
  8500  18.3  64.9  205   6  3   9.7   5.3 |  19.1  66.4  200   5  3   9.2   5.0
  8250  19.0  66.2  205   6  3  10.3   5.7 |  19.8  67.6  200   5  3  10.2   5.6
  8000  19.8  67.6  205   6  3  10.2   5.6 |  20.6  69.1  195   4  2   9.5   5.2
  7750  20.5  68.9  205   6  3   9.8   5.4 |  21.2  70.2  195   4  2   8.1   4.4
  7500  21.2  70.2  205   6  3  10.1   5.5 |  21.8  71.2  195   4  2   9.0   4.9
  7250  22.0  71.6  205   6  3  10.5   5.8 |  22.6  72.7  195   3  2  10.3   5.7
  7000  22.8  73.0  205   6  3  10.3   5.6 |  23.3  73.9  195   3  2  10.2   5.6
  6750  23.5  74.3  205   6  3   9.5   5.2 |  24.0  75.2  200   3  2   8.7   4.8
  6500  24.3  75.7  210   6  3  10.1   5.5 |  24.7  76.5  200   3  2   9.3   5.1
  6250  25.0  77.0  210   5  3  11.1   6.1 |  25.4  77.7  200   3  1  10.5   5.8
  6000  25.8  78.4  210   5  3   9.9   5.5 |  26.2  79.2  205   3  1  10.2   5.6
  5750  26.6  79.9  210   5  3  12.0   6.6 |  27.0  80.6  210   3  1   9.9   5.5
  5500  27.7  81.9  210   5  3  20.7  11.3 |  27.7  81.9  215   2  1  10.6   5.8
________________________________________________________________________________

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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