Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290135
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1935 MDT Saturday, May 28, 2016

This forecast is for Sunday, May 29, 2016:

If the trigger temperature of 70.3 F/21.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 825 ft/min (4.2 m/s)
   Maximum height of thermals.................. 14502 ft MSL (9195 ft AGL)

Forecast maximum temperature................... 75.0 F/24.3 C
Time of trigger temperature.................... 1200 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8061 ft MSL (2755 ft AGL)
Thermal soaring outlook for Monday 05/30....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17615 ft MSL (12308 ft AGL)
Wave soaring outlook for Monday 05/30.......... Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 05:34:44 / 20:19:04 MDT
Total possible sunshine........... 14 hr 44 min 19 sec (884 min 19 sec)
Altitude of sun at 12:57:05 MDT... 71.98 degrees

Upper air data from numerical model forecast valid on 05/29/2016 at 0600 MDT

Freezing level.................. 13053 ft MSL (7746 ft AGL)
Convective condensation level... 14933 ft MSL (9626 ft AGL)
Lifted condensation level....... 14918 ft MSL (9611 ft AGL)
Lifted index.................... -2.4
K index......................... +19.2

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  -58.1 -72.6   245   26   14   0.6   0.3      M     M       M      M    M
 45000  -57.5 -71.5   245   28   14  -2.4  -1.3      M     M       M      M    M
 40000  -61.2 -78.2   255   30   15  -2.2  -1.2      M     M       M      M    M
 38000  -58.9 -74.0   260   29   15   6.0   3.3      M     M       M      M    M
 36000  -55.3 -67.5   265   28   14   6.0   3.3      M     M       M      M    M
 34000  -51.3 -60.3   270   27   14   7.7   4.2      M     M       M      M    M
 32000  -46.1 -51.0   270   27   14   7.6   4.2      M     M       M      M    M
 30000  -41.3 -42.3   275   27   14   8.5   4.7   33.5  92.4     7.3      M    M
 29000  -38.7 -37.7   275   26   14   8.5   4.7   33.0  91.4     7.0      M    M
 28000  -36.2 -33.2   275   26   13   8.5   4.7   32.6  90.7     6.7      M    M
 27000  -33.7 -28.7   275   25   13   8.4   4.6   32.1  89.8     6.4      M    M
 26000  -31.2 -24.2   280   23   12   8.4   4.6   31.5  88.8     6.0      M    M
 25000  -28.7 -19.7   280   21   11   8.4   4.6   31.1  87.9     5.7      M    M
 24000  -26.2 -15.2   285   20   10   7.9   4.3   30.5  86.9     5.3      M    M
 23000  -23.9 -11.0   290   20   10   7.9   4.4   29.8  85.6     4.7      M    M
 22000  -21.5  -6.7   295   19   10   8.0   4.4   29.2  84.6     4.3      M    M
 21000  -19.2  -2.6   300   20   10   7.7   4.2   28.5  83.3     3.7      M    M
 20000  -16.9   1.6   295   20   10   7.7   4.2   27.7  81.9     3.1      M    M
 19500  -15.8   3.6   295   20   11   7.7   4.2   27.4  81.3     2.8      M    M
 19000  -14.7   5.5   295   21   11   7.8   4.3   27.1  80.8     2.5      M    M
 18500  -13.5   7.7   290   21   11   7.9   4.3   26.8  80.2     2.2      M    M
 18000  -12.3   9.9   290   20   10   7.9   4.3   26.5  79.6     1.9      M    M
 17500  -11.2  11.8   285   20   10   7.9   4.3   26.1  79.1     1.6      M    M
 17000  -10.0  14.0   285   19   10   7.9   4.3   25.8  78.5     1.4      M    M
 16500   -8.2  17.2   275   18    9   7.8   4.3   25.4  77.7     0.9      M    M
 16000   -7.1  19.2   275   17    9   7.8   4.3   25.0  77.1     0.7      M    M
 15500   -5.9  21.4   270   15    8   8.1   4.4   24.7  76.5     0.4      M    M
 15000   -4.6  23.7   265   14    7   8.2   4.5   24.5  76.1     0.2      M    M
 14500   -3.4  25.9   260   13    6   8.3   4.5   24.2  75.6    -0.0    815  4.1
 14000   -2.2  28.0   255   11    6   8.3   4.5   24.0  75.2    -0.3    764  3.9
 13500   -0.9  30.4   250   11    5   8.3   4.6   23.7  74.7    -0.5    712  3.6
 13000    0.3  32.5   245   10    5   8.5   4.6   23.5  74.3    -0.7    660  3.4
 12500    1.5  34.7   235    9    5   8.5   4.6   23.3  74.0    -1.0    609  3.1
 12000    2.7  36.9   230    9    4   8.2   4.5   23.1  73.5    -1.2    558  2.8
 11500    3.9  39.0   225    8    4   8.2   4.5   22.8  73.1    -1.5    507  2.6
 11000    5.1  41.2   215    8    4   8.5   4.7   22.6  72.7    -1.8    456  2.3
 10500    6.4  43.5   210    7    4   7.5   4.1   22.4  72.4    -2.0    404  2.1
 10250    6.8  44.2   210    7    4   5.0   2.8   22.2  71.9    -2.3    384  1.9
 10000    7.2  45.0   210    7    3   8.6   4.7   21.9  71.3    -2.6    363  1.8
  9750    8.0  46.4   210    6    3  11.8   6.5   22.0  71.5    -2.5    332  1.7
  9500    8.8  47.8   210    6    3  10.5   5.8   22.1  71.7    -2.5    300  1.5
  9250    9.5  49.1   215    5    3   7.7   4.2   22.0  71.7    -2.5    272  1.4
  9000   10.1  50.2   215    5    3   8.0   4.4   21.8  71.3    -2.7    249  1.3
  8750   10.8  51.4   220    5    3  10.4   5.7   21.8  71.3    -2.7    220  1.1
  8500   11.5  52.7   225    5    3   9.0   5.0   21.8  71.3    -2.7    190  1.0
  8250   12.2  54.0   230    5    3   7.8   4.3   21.7  71.1    -2.8    164  0.8
  8000   12.7  54.9   235    6    3   7.3   4.0   21.6  70.8    -3.0    141  0.7
  7750   13.2  55.8   235    6    3   7.4   4.1   21.4  70.5    -3.2    117  0.6
  7500   13.8  56.8   235    7    3   6.3   3.5   21.2  70.1    -3.4     94  0.5
  7250   14.1  57.4   235    7    4   5.1   2.8   20.8  69.5    -3.8     75  0.4
  7000   14.5  58.1   230    7    4   5.9   3.2   20.5  68.9    -4.2     56  0.3
  6750   14.9  58.8   230    8    4   4.7   2.6   20.2  68.4    -4.5     37  0.2
  6500   15.0  59.0   230    8    4  -2.3  -1.3   19.6  67.3    -5.1     26  0.1
  6250   14.6  58.3   235    7    4  -8.1  -4.5   18.4  65.1    -6.4     33  0.2
  6000   14.1  57.4   240    7    3  -1.3  -0.7   17.2  63.0    -7.6     40  0.2
  5750   13.9  57.0   250    6    3 -10.7  -5.9   16.3  61.4    -8.5     37  0.2
  5500   11.7  53.1   235    5    3 -45.3 -24.8   13.5  56.3   -11.4     96  0.5

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

           05/29/2016 at 0900 MDT          |       05/29/2016 at 1200 MDT
                                           |
K index... +15.6  LI... +0.5               | K index... +15.2  LI... -1.9
CAPE... +0.2  CIN... -5.5                  | CAPE... +407.7  CIN... -50.0
                                           |
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 -57.9 -72.2  250  26 13   0.1   0.1 | -57.8 -72.0  255  26 13   0.3   0.2
 45000 -58.1 -72.6  245  28 15  -2.2  -1.2 | -57.7 -71.9  250  29 15  -2.6  -1.4
 40000 -61.5 -78.7  250  25 13  -2.0  -1.1 | -61.8 -79.2  260  19 10  -2.4  -1.3
 38000 -59.0 -74.2  255  24 12   6.2   3.4 | -59.2 -74.6  255  18  9   6.5   3.6
 36000 -55.3 -67.5  255  23 12   6.2   3.4 | -55.3 -67.5  250  18  9   6.5   3.6
 34000 -51.2 -60.2  260  22 11   7.9   4.3 | -50.5 -58.9  255  17  9   7.9   4.3
 32000 -45.8 -50.4  270  21 11   7.9   4.3 | -45.8 -50.4  275  14  7   7.9   4.3
 30000 -40.9 -41.6  265  21 11   8.4   4.6 | -40.9 -41.6  275  13  7   8.4   4.6
 29000 -38.4 -37.1  260  21 11   8.4   4.6 | -38.3 -36.9  270  14  7   8.4   4.6
 28000 -35.9 -32.6  260  22 11   8.4   4.6 | -35.8 -32.4  265  15  8   8.4   4.6
 27000 -33.4 -28.1  255  21 11   8.5   4.7 | -33.3 -27.9  255  16  8   8.3   4.6
 26000 -30.8 -23.4  260  19 10   8.5   4.7 | -30.8 -23.4  250  16  8   8.3   4.6
 25000 -28.3 -18.9  260  17  9   8.5   4.7 | -28.3 -18.9  240  17  9   8.3   4.6
 24000 -25.8 -14.4  260  16  8   7.9   4.3 | -25.9 -14.6  240  17  9   8.3   4.5
 23000 -23.5 -10.3  260  14  7   7.9   4.4 | -23.4 -10.1  235  17  9   8.3   4.5
 22000 -21.1  -6.0  260  13  7   8.0   4.4 | -20.9  -5.6  235  16  8   8.3   4.6
 21000 -18.9  -2.0  265  13  7   7.4   4.0 | -18.6  -1.5  240  16  8   7.5   4.1
 20000 -16.7   1.9  270  13  7   7.4   4.0 | -16.3   2.7  245  16  8   7.5   4.1
 19500 -15.6   3.9  270  14  7   7.4   4.0 | -15.2   4.6  245  16  8   7.6   4.1
 19000 -14.5   5.9  275  14  7   7.5   4.1 | -14.1   6.6  250  17  9   7.8   4.3
 18500 -13.3   8.1  275  14  7   7.6   4.2 | -12.9   8.8  250  17  9   8.2   4.5
 18000 -12.2  10.0  275  15  8   7.6   4.2 | -11.7  10.9  255  17  9   8.2   4.5
 17500 -11.1  12.0  275  15  8   7.7   4.2 |  -9.9  14.2  255  16  8   7.9   4.3
 17000  -9.3  15.3  280  15  7   7.7   4.2 |  -8.7  16.3  255  16  8   7.9   4.3
 16500  -8.1  17.4  280  14  7   8.3   4.6 |  -7.6  18.3  255  15  8   8.0   4.4
 16000  -6.9  19.6  275  14  7   8.3   4.5 |  -6.4  20.5  255  14  7   8.0   4.4
 15500  -5.7  21.7  275  14  7   8.2   4.5 |  -5.2  22.6  260  13  7   8.4   4.6
 15000  -4.5  23.9  270  13  7   8.2   4.5 |  -3.9  25.0  260  12  6   8.6   4.7
 14500  -3.3  26.1  270  12  6   8.3   4.6 |  -2.6  27.3  260  11  6   8.6   4.7
 14000  -2.1  28.2  265  12  6   8.5   4.6 |  -1.4  29.5  260  11  5   8.6   4.7
 13500  -0.8  30.6  260  11  6   8.5   4.7 |  -0.1  31.8  260  10  5   8.5   4.7
 13000   0.5  32.9  255  11  5   8.7   4.8 |   1.1  34.0  260   9  5   8.3   4.5
 12500   1.8  35.2  250  10  5   8.7   4.8 |   2.4  36.3  260   8  4   8.3   4.6
 12000   3.1  37.6  245  10  5   8.8   4.8 |   3.6  38.5  255   7  4   8.6   4.7
 11500   4.4  39.9  245   9  5   8.8   4.8 |   4.9  40.8  245   6  3   8.6   4.7
 11000   5.6  42.1  240   8  4   7.9   4.3 |   6.2  43.2  240   6  3   8.4   4.6
 10500   6.8  44.2  235   7  4   6.7   3.7 |   7.5  45.5  235   5  3   6.7   3.7
 10250   7.2  45.0  235   7  4   4.6   2.5 |   7.8  46.0  230   5  2   4.9   2.7
 10000   7.6  45.7  230   6  3   8.4   4.6 |   8.3  46.9  230   4  2   8.5   4.7
  9750   8.4  47.1  230   6  3  11.2   6.1 |   9.1  48.4  225   4  2  10.3   5.7
  9500   9.2  48.6  230   5  3   9.9   5.4 |   9.8  49.6  215   3  2   9.1   5.0
  9250   9.8  49.6  230   4  2   7.2   4.0 |  10.4  50.7  210   3  2   6.9   3.8
  9000  10.3  50.5  235   4  2   7.6   4.1 |  10.9  51.6  205   3  1   6.9   3.8
  8750  10.9  51.6  245   3  2   9.6   5.2 |  11.4  52.5  195   2  1   7.9   4.4
  8500  11.6  52.9  255   3  1   8.3   4.5 |  12.0  53.6  170   1  1   7.7   4.2
  8250  12.1  53.8  270   3  1   7.0   3.8 |  12.5  54.5  115   1  0   7.9   4.3
  8000  12.6  54.7  285   3  1   6.8   3.7 |  13.0  55.4  060   2  1   8.2   4.5
  7750  13.1  55.6  300   3  1   7.6   4.2 |  13.5  56.3  050   3  1   8.3   4.5
  7500  13.6  56.5  310   3  1   6.1   3.3 |  14.1  57.4  040   4  2   9.4   5.2
  7250  14.0  57.2  315   3  2   4.5   2.5 |  14.8  58.6  040   4  2  10.5   5.7
  7000  14.3  57.7  320   3  2   5.0   2.7 |  15.6  60.1  040   4  2  10.1   5.5
  6750  14.6  58.3  320   4  2   4.2   2.3 |  16.3  61.3  040   4  2  10.2   5.6
  6500  14.9  58.8  320   3  2   1.9   1.1 |  17.1  62.8  035   4  2  10.7   5.9
  6250  15.0  59.0  320   3  2   3.0   1.6 |  17.9  64.2  035   4  2  11.8   6.4
  6000  15.1  59.2  320   3  1  -3.1  -1.7 |  18.8  65.8  035   4  2   9.1   5.0
  5750  14.7  58.5  315   2  1   2.6   1.5 |  19.5  67.1  035   4  2  14.2   7.8
  5500  15.9  60.6  315   2  1  30.8  16.9 |  21.1  70.0  030   4  2  30.1  16.5

           05/29/2016 at 1500 MDT          |       05/29/2016 at 1800 MDT
                                           |
K index... +24.1  LI... -2.7               | K index... +24.6  LI... -0.7
CAPE... +539.5  CIN... -9.3                | CAPE... +33.0  CIN... -97.5
                                           |
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 -57.8 -72.0  255  25 13   0.1   0.1 | -58.0 -72.4  245  25 13   0.6   0.3
 45000 -58.0 -72.4  255  28 15  -2.5  -1.4 | -57.6 -71.7  250  24 12  -3.0  -1.6
 40000 -61.8 -79.2  255  19 10  -2.2  -1.2 | -62.3 -80.1  250  18  9  -4.0  -2.2
 38000 -59.4 -74.9  255  20 10   6.0   3.3 | -59.2 -74.6  245  19 10   6.6   3.6
 36000 -55.4 -67.7  255  22 11   6.0   3.3 | -55.3 -67.5  240  21 11   6.6   3.6
 34000 -50.7 -59.3  255  23 12   9.1   5.0 | -50.4 -58.7  235  21 11   9.5   5.2
 32000 -45.3 -49.5  255  22 11   9.1   5.0 | -44.8 -48.6  235  19 10   9.5   5.2
 30000 -39.9 -39.8  255  21 11   8.9   4.9 | -39.2 -38.6  235  17  9   9.1   5.0
 29000 -37.2 -35.0  255  20 10   8.9   4.9 | -35.8 -32.4  235  16  8   9.1   5.0
 28000 -34.5 -30.1  250  19 10   8.9   4.9 | -33.1 -27.6  235  14  7   9.2   5.1
 27000 -32.1 -25.8  250  18  9   7.9   4.3 | -30.7 -23.3  235  13  7   8.0   4.4
 26000 -29.7 -21.5  250  17  9   7.9   4.3 | -28.3 -18.9  240  11  6   8.0   4.4
 25000 -27.4 -17.3  245  16  8   7.8   4.3 | -25.9 -14.6  245  10  5   8.0   4.4
 24000 -25.1 -13.2  245  15  8   7.2   3.9 | -23.7 -10.7  250   9  4   7.4   4.1
 23000 -23.0  -9.4  240  15  8   7.2   3.9 | -21.5  -6.7  260   8  4   7.4   4.1
 22000 -20.9  -5.6  240  14  7   7.2   4.0 | -19.3  -2.7  275   7  4   7.4   4.1
 21000 -18.7  -1.7  240  13  7   7.6   4.1 | -17.2   1.0  285   7  4   6.9   3.8
 20000 -16.4   2.5  245  11  6   7.6   4.2 | -15.2   4.6  295   8  4   6.9   3.8
 19500 -15.3   4.5  250  10  5   7.6   4.2 | -14.2   6.4  300   8  4   6.9   3.8
 19000 -14.2   6.4  255   9  5   7.6   4.2 | -13.2   8.2  300   8  4   6.8   3.7
 18500 -12.5   9.5  255   9  5   7.7   4.2 | -12.2  10.0  305   8  4   6.6   3.6
 18000 -11.3  11.7  255   9  5   7.8   4.3 | -11.2  11.8  305   8  4   6.6   3.6
 17500 -10.2  13.6  255   9  5   7.8   4.3 | -10.2  13.6  305   8  4   7.0   3.8
 17000  -9.0  15.8  250   9  5   7.8   4.3 |  -9.2  15.4  305   7  4   7.0   3.8
 16500  -7.8  18.0  250   9  5   8.4   4.6 |  -8.2  17.2  305   7  3   7.2   4.0
 16000  -6.6  20.1  245   9  5   8.4   4.6 |  -7.1  19.2  300   5  3   7.4   4.1
 15500  -5.3  22.5  240   9  5   8.4   4.6 |  -6.0  21.2  295   4  2   7.5   4.1
 15000  -4.1  24.6  240   9  4   8.4   4.6 |  -4.3  24.3  260   3  1   7.8   4.3
 14500  -2.8  27.0  235   8  4   8.6   4.7 |  -3.2  26.2  220   3  1   7.7   4.2
 14000  -1.5  29.3  235   8  4   8.8   4.8 |  -2.1  28.2  190   3  2   7.6   4.1
 13500  -0.2  31.6  235   7  4   8.8   4.8 |  -1.0  30.2  175   5  2   7.8   4.3
 13000   1.1  34.0  235   6  3   8.8   4.9 |   0.2  32.4  170   6  3   8.4   4.6
 12500   2.4  36.3  235   5  3   8.9   4.9 |   1.4  34.5  170   7  4   8.5   4.6
 12000   3.7  38.7  225   4  2   8.9   4.9 |   2.7  36.9  170   8  4   8.9   4.9
 11500   5.1  41.2  205   2  1   8.9   4.9 |   4.0  39.2  170   8  4   8.9   4.9
 11000   6.4  43.5  165   1  1   9.1   5.0 |   5.3  41.5  175   9  5   8.8   4.8
 10500   7.7  45.9  100   1  1   7.0   3.8 |   6.6  43.9  175   9  5   6.8   3.7
 10250   8.1  46.6  085   1  1   6.2   3.4 |   7.0  44.6  175  10  5   5.4   3.0
 10000   8.7  47.7  080   2  1  10.5   5.8 |   7.6  45.7  180  10  5   9.9   5.4
  9750   9.5  49.1  075   2  1  11.5   6.3 |   8.4  47.1  180  10  5  11.8   6.5
  9500  10.3  50.5  070   2  1  10.8   5.9 |   9.2  48.6  185  10  5  10.5   5.8
  9250  11.0  51.8  070   2  1   9.0   4.9 |   9.9  49.8  185  11  6   7.8   4.3
  9000  11.7  53.1  065   2  1   9.5   5.2 |  10.5  50.9  190  11  6   8.1   4.4
  8750  12.4  54.3  065   2  1  10.8   5.9 |  11.2  52.2  195  12  6  10.0   5.5
  8500  13.2  55.8  060   2  1  10.4   5.7 |  11.9  53.4  195  12  6   8.8   4.8
  8250  14.0  57.2  060   2  1  10.4   5.7 |  12.5  54.5  200  13  7   7.9   4.3
  8000  14.8  58.6  060   2  1  10.2   5.6 |  13.0  55.4  210  14  7   7.4   4.0
  7750  15.5  59.9  055   2  1   9.7   5.3 |  13.6  56.5  215  15  8   7.0   3.9
  7500  16.3  61.3  050   2  1  10.0   5.5 |  14.1  57.4  215  17  9   6.3   3.5
  7250  17.0  62.6  050   2  1  10.4   5.7 |  14.5  58.1  220  19 10   5.8   3.2
  7000  17.8  64.0  045   2  1  10.2   5.6 |  14.9  58.8  225  21 11   6.0   3.3
  6750  18.5  65.3  040   2  1   9.8   5.4 |  15.4  59.7  225  23 12   5.6   3.1
  6500  19.3  66.7  040   2  1  10.4   5.7 |  15.7  60.3  230  24 12   4.4   2.4
  6250  20.1  68.2  035   2  1  11.5   6.3 |  16.0  60.8  230  23 12   4.6   2.5
  6000  20.9  69.6  035   2  1   9.5   5.2 |  16.2  61.2  230  22 11   2.8   1.5
  5750  21.7  71.1  030   2  1  13.3   7.3 |  16.3  61.3  230  22 11   5.8   3.2
  5500  23.1  73.6  030   2  1  26.1  14.3 |  17.1  62.8  230  19 10  17.0   9.3
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613



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