Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 031255
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0655 MDT Sunday, May 3, 2015

This forecast is for Sunday, May 3, 2015:

If the trigger temperature of 70.3 F/21.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 785 ft/min (4.0 m/s)
   Maximum height of thermals.................. 14878 ft MSL (9593 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6693 ft MSL (1407 ft AGL)
Thermal soaring outlook for Monday 05/04....... Poor

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....................... 22773 ft MSL (17488 ft AGL)
Wave soaring outlook for Monday 05/04.......... Poor

Remarks...

Sunrise/Sunset.................... 05:57:55 / 19:54:37 MDT
Total possible sunshine........... 13 hr 56 min 42 sec (836 min 42 sec)
Altitude of sun at 12:56:26 MDT... 65.97 degrees

Upper air data from rawinsonde observation taken on 05/03/2015 at 0600 MDT

Freezing level.................. 12870 ft MSL (7585 ft AGL)
Convective condensation level... 16535 ft MSL (11250 ft AGL)
Lifted condensation level....... 16366 ft MSL (11081 ft AGL)
Lifted index.................... -0.7
K index......................... +17.0

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  -62.3 -80.1   280   33   17  -0.6  -0.3   96.0 204.9    41.5      M    M
 45000  -63.6 -82.5   260   38   19 -12.0  -6.6   68.0 154.5    27.5      M    M
 40000  -63.4 -82.1   240   31   16   3.4   1.9   45.2 113.4    14.4      M    M
 38000  -59.4 -74.9   245   29   15   6.2   3.4   42.5 108.5    13.0      M    M
 36000  -55.7 -68.3   245   34   18   1.8   1.0   39.4 102.9    11.2      M    M
 34000  -52.8 -63.0   250   39   20   8.6   4.7   35.3  95.5     8.5      M    M
 32000  -48.0 -54.4   255   42   21   6.2   3.4   32.8  91.0     7.0      M    M
 30000  -42.7 -44.9   255   43   22   9.3   5.1   32.0  89.7     6.6      M    M
 29000  -39.9 -39.8   255   44   22   9.2   5.1   31.9  89.3     6.5      M    M
 28000  -37.2 -35.0   255   37   19   9.0   4.9   31.6  88.9     6.4      M    M
 27000  -34.5 -30.1   255   30   16   8.6   4.7   31.2  88.2     6.2      M    M
 26000  -32.0 -25.6   255   24   12   8.6   4.7   30.8  87.5     5.9      M    M
 25000  -29.4 -20.9   255   24   12   8.0   4.4   30.3  86.6     5.6      M    M
 24000  -27.3 -17.1   260   23   12   7.2   4.0   29.4  84.9     4.9      M    M
 23000  -24.9 -12.8   270   22   11   8.3   4.6   28.8  83.8     4.4      M    M
 22000  -22.4  -8.3   275   21   11   7.8   4.3   28.3  82.9     4.0      M    M
 21000  -20.2  -4.4   280   20   10   8.0   4.4   27.4  81.2     3.2      M    M
 20000  -17.7   0.1   290   20   10   6.2   3.4   26.9  80.4     2.8      M    M
 19500  -16.8   1.8   295   20   10   6.4   3.5   26.3  79.3     2.4      M    M
 19000  -15.8   3.6   300   21   11   5.4   3.0   25.7  78.3     1.9      M    M
 18500  -15.1   4.8   305   21   11   6.9   3.8   24.9  76.8     1.1      M    M
 18000  -13.9   7.0   300   20   10   8.7   4.8   24.6  76.3     0.9      M    M
 17500  -12.6   9.3   295   19   10   8.8   4.9   24.4  76.0     0.7      M    M
 17000  -11.2  11.8   290   19   10   8.9   4.9   24.3  75.7     0.6      M    M
 16500   -9.9  14.2   285   18    9   8.9   4.9   24.1  75.5     0.5      M    M
 16000   -8.6  16.5   280   18    9   8.9   4.9   24.0  75.3     0.4      M    M
 15500   -6.6  20.1   285   17    9   9.1   5.0   23.8  74.9     0.2      M    M
 15000   -5.3  22.5   290   17    9   8.6   4.7   23.7  74.7     0.0      M    M
 14500   -4.0  24.8   295   17    9   8.7   4.8   23.6  74.4    -0.1    833  4.2
 14000   -2.7  27.1   300   17    9   8.7   4.8   23.4  74.2    -0.3    779  4.0
 13500   -1.4  29.5   300   18    9   8.7   4.8   23.2  73.8    -0.5    726  3.7
 13000   -0.1  31.8   295   19   10   8.7   4.8   23.1  73.5    -0.7    672  3.4
 12500    1.2  34.2   295   20   10   8.7   4.8   22.9  73.3    -0.8    619  3.1
 12000    2.4  36.3   295   21   11   8.7   4.8   22.8  73.0    -1.0    565  2.9
 11500    3.7  38.7   300   20   10   8.7   4.8   22.6  72.6    -1.2    512  2.6
 11000    5.0  41.0   305   20   10   8.7   4.8   22.4  72.3    -1.4    459  2.3
 10500    6.3  43.3   305   19   10   8.7   4.8   22.2  72.0    -1.6    405  2.1
 10250    7.0  44.6   310   19   10   8.7   4.8   22.1  71.8    -1.7    378  1.9
 10000    7.6  45.7   310   19   10   8.6   4.7   22.0  71.7    -1.7    352  1.8
  9750    8.2  46.8   305   20   10   8.6   4.7   22.0  71.5    -1.8    325  1.7
  9500    8.9  48.0   305   20   10   8.6   4.7   21.9  71.4    -1.9    299  1.5
  9250    9.5  49.1   300   21   11   8.6   4.7   21.8  71.3    -2.0    272  1.4
  9000   10.2  50.4   300   21   11   8.6   4.7   21.7  71.1    -2.1    246  1.2
  8750   10.8  51.4   300   19   10   8.6   4.7   21.6  71.0    -2.2    219  1.1
  8500   11.4  52.5   295   18    9   8.6   4.7   21.6  70.8    -2.3    193  1.0
  8250   12.1  53.8   295   16    8   8.6   4.7   21.5  70.7    -2.4    166  0.8
  8000   12.7  54.9   290   15    8   8.6   4.7   21.4  70.5    -2.5    139  0.7
  7750   13.3  55.9   290   14    7   8.6   4.7   21.3  70.3    -2.6    113  0.6
  7500   14.0  57.2   290   14    7   8.6   4.7   21.2  70.2    -2.7     86  0.4
  7250   14.6  58.3   290   13    7   8.6   4.7   21.1  70.0    -2.8     60  0.3
  7000   15.3  59.5   290   12    6   8.8   4.8   21.0  69.9    -2.9     33  0.2
  6750   15.9  60.6   285   11    6   8.0   4.4   20.9  69.7    -3.0      7  0.0
  6500   16.5  61.7   280   10    5  10.8   5.9   20.8  69.5    -3.1      M    M
  6250   16.9  62.4   275    9    5 -11.2  -6.1   20.5  68.8    -3.5      M    M
  6000   15.4  59.7   265    8    4  -8.8  -4.8   18.3  64.9    -5.7      M    M
  5750   15.9  60.6   240    6    3   9.4   5.2   18.1  64.5    -6.0      M    M
  5500   15.0  59.0   205    7    3 -40.0 -22.0   16.5  61.8    -7.6      M    M

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

           05/03/2015 at 0900 MDT          |       05/03/2015 at 1200 MDT
                                           |
K index... +18.0  LI... +273.0             | K index... +22.1  LI... +270.9
CAPE... +9.3  CIN... -74.5                 | CAPE... +422.5  CIN... -17.2
                                           |
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 -60.5 -76.9  275  30 16  -0.1  -0.0 | -60.4 -76.7  275  33 17   0.0   0.0
 45000 -60.6 -77.1  275  32 17  -0.8  -0.4 | -60.4 -76.7  270  35 18  -1.2  -0.6
 40000 -62.0 -79.6  255  32 16  -1.0  -0.6 | -62.5 -80.5  260  33 17  -1.4  -0.8
 38000 -60.1 -76.2  255  32 16   5.9   3.3 | -60.4 -76.7  255  32 17   6.7   3.7
 36000 -56.1 -69.0  250  31 16   5.9   3.3 | -55.9 -68.6  250  31 16   6.7   3.7
 34000 -52.1 -61.8  250  31 16   7.6   4.2 | -51.7 -61.1  250  31 16   7.2   3.9
 32000 -47.5 -53.5  250  33 17   7.6   4.2 | -47.4 -53.3  245  32 16   7.2   3.9
 30000 -42.7 -44.9  250  32 16   8.7   4.8 | -42.7 -44.9  245  31 16   8.9   4.9
 29000 -40.1 -40.2  255  29 15   8.7   4.8 | -40.0 -40.0  250  30 15   8.9   4.9
 28000 -37.5 -35.5  255  26 13   8.7   4.8 | -37.4 -35.3  250  28 14   8.9   4.9
 27000 -34.9 -30.8  260  23 12   8.5   4.7 | -34.7 -30.5  255  26 13   8.5   4.6
 26000 -32.3 -26.1  260  20 10   8.5   4.7 | -32.2 -26.0  250  23 12   8.5   4.7
 25000 -29.8 -21.6  260  17  9   8.6   4.7 | -29.6 -21.3  245  20 10   8.5   4.7
 24000 -27.2 -17.0  260  15  8   8.2   4.5 | -27.2 -17.0  245  17  9   7.4   4.0
 23000 -24.8 -12.6  265  14  7   8.2   4.5 | -25.0 -13.0  245  16  8   7.4   4.0
 22000 -22.3  -8.1  265  13  7   8.2   4.5 | -22.8  -9.0  250  15  8   7.4   4.0
 21000 -19.9  -3.8  270  13  7   7.4   4.0 | -20.5  -4.9  255  14  7   7.8   4.3
 20000 -17.7   0.1  280  12  6   7.4   4.1 | -18.2  -0.8  260  14  7   7.8   4.3
 19500 -16.6   2.1  285  12  6   7.4   4.1 | -17.1   1.2  265  14  7   7.8   4.3
 19000 -15.5   4.1  285  11  6   7.4   4.1 | -15.9   3.4  265  13  7   7.7   4.2
 18500 -14.4   6.1  290  11  6   8.2   4.5 | -14.1   6.6  275  13  7   8.3   4.5
 18000 -12.5   9.5  300  12  6   8.2   4.5 | -12.9   8.8  280  13  6   8.3   4.6
 17500 -11.3  11.7  305  12  6   8.2   4.5 | -11.7  10.9  285  12  6   8.2   4.5
 17000 -10.1  13.8  310  12  6   8.2   4.5 | -10.5  13.1  285  12  6   8.2   4.5
 16500  -8.9  16.0  315  13  6   8.3   4.6 |  -9.2  15.4  290  12  6   8.8   4.8
 16000  -7.6  18.3  320  13  7   8.4   4.6 |  -7.9  17.8  295  12  6   9.2   5.0
 15500  -6.4  20.5  325  13  7   8.4   4.6 |  -6.5  20.3  300  13  7   9.2   5.0
 15000  -5.2  22.6  325  13  7   8.4   4.6 |  -5.2  22.6  300  13  7   9.1   5.0
 14500  -3.9  25.0  330  14  7   8.4   4.6 |  -3.8  25.2  305  13  7   9.2   5.0
 14000  -2.7  27.1  330  14  7   8.6   4.7 |  -2.5  27.5  305  13  7   8.8   4.8
 13500  -1.4  29.5  330  13  7   8.5   4.7 |  -1.2  29.8  305  12  6   8.9   4.9
 13000  -0.2  31.6  335  13  7   8.8   4.8 |   0.1  32.2  310  11  6   8.7   4.8
 12500   1.2  34.2  335  13  7   8.8   4.8 |   1.4  34.5  315  10  5   8.7   4.8
 12000   2.5  36.5  335  13  7   9.0   4.9 |   2.7  36.9  320   9  4   8.7   4.8
 11500   3.8  38.8  335  13  7   9.1   5.0 |   4.0  39.2  325   8  4   8.8   4.8
 11000   5.1  41.2  335  13  7   8.2   4.5 |   5.2  41.4  330   7  3   7.7   4.2
 10500   6.3  43.3  335  13  7   7.4   4.0 |   6.3  43.3  340   6  3   6.8   3.7
 10250   6.9  44.4  335  13  7  10.8   5.9 |   6.9  44.4  345   6  3  10.5   5.8
 10000   7.8  46.0  335  13  7  11.6   6.4 |   7.8  46.0  350   5  3  10.9   6.0
  9750   8.5  47.3  330  13  7   8.6   4.7 |   8.4  47.1  360   5  3   7.6   4.2
  9500   9.2  48.6  330  13  7   9.6   5.2 |   9.0  48.2  005   5  3   8.2   4.5
  9250   9.9  49.8  325  13  7   8.6   4.7 |   9.6  49.3  015   5  2   9.2   5.0
  9000  10.5  50.9  325  14  7   9.0   4.9 |  10.3  50.5  020   5  2  10.0   5.5
  8750  11.2  52.2  320  14  7   9.9   5.4 |  11.0  51.8  020   5  2   9.4   5.2
  8500  12.0  53.6  315  14  7   9.7   5.3 |  11.7  53.1  020   5  2   9.2   5.0
  8250  12.7  54.9  315  15  8   9.5   5.2 |  12.4  54.3  025   5  2  10.6   5.8
  8000  13.4  56.1  310  15  8   8.8   4.8 |  13.2  55.8  025   5  2  11.0   6.0
  7750  14.0  57.2  305  16  8   8.4   4.6 |  14.0  57.2  025   5  2   9.2   5.1
  7500  14.6  58.3  305  16  8   8.3   4.6 |  14.7  58.5  025   5  2   9.3   5.1
  7250  15.2  59.4  305  16  8   7.9   4.4 |  15.4  59.7  025   4  2  10.0   5.5
  7000  15.8  60.4  300  16  8   7.3   4.0 |  16.2  61.2  025   4  2  10.3   5.7
  6750  16.3  61.3  300  16  8   7.4   4.1 |  16.9  62.4  025   4  2   9.5   5.2
  6500  16.8  62.2  300  15  8   4.4   2.4 |  17.6  63.7  025   4  2  10.0   5.5
  6250  16.9  62.4  300  13  7   0.1   0.0 |  18.4  65.1  025   4  2  11.3   6.2
  6000  16.8  62.2  295  10  5  -0.2  -0.1 |  19.3  66.7  025   4  2  11.1   6.1
  5750  16.6  61.9  285   8  4  -3.9  -2.1 |  20.1  68.2  020   4  2  11.3   6.2
  5500  16.0  60.8  260   5  3  -5.2  -2.8 |  21.1  70.0  020   4  2  17.1   9.4

           05/03/2015 at 1500 MDT          |       05/03/2015 at 1800 MDT
                                           |
K index... +23.1  LI... +270.3             | K index... +27.6  LI... +271.3
CAPE... +432.7  CIN... -8.8                | CAPE... +310.1  CIN... -29.7
                                           |
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 -61.0 -77.8  275  36 18   0.3   0.1 | -60.8 -77.4  275  37 19   0.0   0.0
 45000 -60.7 -77.3  270  34 17  -0.9  -0.5 | -60.8 -77.4  270  36 19  -1.9  -1.1
 40000 -62.5 -80.5  260  35 18  -1.1  -0.6 | -64.8 -84.6  250  35 18  -2.3  -1.3
 38000 -60.1 -76.2  255  34 18   6.3   3.5 | -61.6 -78.9  245  34 17   8.5   4.7
 36000 -56.3 -69.3  250  33 17   6.3   3.5 | -56.5 -69.7  240  31 16   8.5   4.7
 34000 -52.0 -61.6  250  32 16   8.9   4.9 | -51.3 -60.3  235  29 15   9.1   5.0
 32000 -46.7 -52.1  250  28 14   8.9   4.9 | -45.8 -50.4  230  26 14   9.1   5.0
 30000 -41.4 -42.5  250  24 13   8.9   4.9 | -40.5 -40.9  230  24 12   8.8   4.8
 29000 -38.1 -36.6  250  22 11   8.8   4.9 | -37.2 -35.0  230  22 11   8.8   4.8
 28000 -35.4 -31.7  250  20 10   8.8   4.8 | -34.6 -30.3  230  20 10   8.8   4.8
 27000 -32.9 -27.2  250  18  9   7.9   4.4 | -32.0 -25.6  230  18  9   8.2   4.5
 26000 -30.5 -22.9  250  16  8   7.9   4.4 | -29.6 -21.3  225  16  8   8.2   4.5
 25000 -28.2 -18.8  255  14  7   8.0   4.4 | -27.2 -17.0  225  14  7   8.2   4.5
 24000 -25.9 -14.6  255  13  7   7.1   3.9 | -24.8 -12.6  220  12  6   7.2   4.0
 23000 -23.8 -10.8  250  12  6   7.2   3.9 | -22.7  -8.9  215  11  5   7.3   4.0
 22000 -21.6  -6.9  245  11  5   7.2   3.9 | -20.5  -4.9  215  10  5   7.3   4.0
 21000 -19.6  -3.3  240   9  5   6.8   3.7 | -18.4  -1.1  210   9  5   6.8   3.7
 20000 -17.5   0.5  240   8  4   6.8   3.7 | -16.4   2.5  205  10  5   6.9   3.8
 19500 -16.5   2.3  240   7  4   6.8   3.7 | -15.4   4.3  205  10  5   6.9   3.8
 19000 -15.5   4.1  240   6  3   6.8   3.7 | -14.4   6.1  205  10  5   6.9   3.8
 18500 -14.5   5.9  245   6  3   7.6   4.2 | -13.4   7.9  200  10  5   6.9   3.8
 18000 -13.4   7.9  245   6  3   7.5   4.1 | -12.4   9.7  200   9  5   6.9   3.8
 17500 -12.2  10.0  245   5  3   7.9   4.3 | -11.3  11.7  200   9  4   6.8   3.7
 17000 -11.0  12.2  250   5  3   8.1   4.4 | -10.4  13.3  195   8  4   6.7   3.7
 16500  -9.8  14.4  260   5  3   8.2   4.5 |  -9.4  15.1  190   7  3   6.7   3.7
 16000  -8.6  16.5  265   5  3   9.0   4.9 |  -8.4  16.9  180   6  3   7.2   3.9
 15500  -6.6  20.1  270   5  3   9.0   4.9 |  -6.8  19.8  155   5  3   7.2   4.0
 15000  -5.2  22.6  270   4  2   9.2   5.0 |  -5.8  21.6  140   5  2   7.3   4.0
 14500  -3.9  25.0  280   3  1   9.2   5.0 |  -4.7  23.5  120   5  3   7.3   4.0
 14000  -2.6  27.3  280   1  1   8.9   4.9 |  -3.5  25.7  110   5  3   8.9   4.9
 13500  -1.3  29.7  110   1  0   9.0   4.9 |  -2.3  27.9  105   5  3   8.5   4.7
 13000  -0.0  32.0  105   2  1   9.1   5.0 |  -0.9  30.4  100   5  3  10.9   6.0
 12500   1.3  34.3  100   2  1   9.1   5.0 |   0.7  33.3  095   5  3  10.9   6.0
 12000   2.6  36.7  100   2  1   9.5   5.2 |   2.2  36.0  090   5  3   9.6   5.3
 11500   4.0  39.2  095   2  1   9.6   5.2 |   3.6  38.5  090   5  3   9.5   5.2
 11000   5.3  41.5  095   2  1   8.1   4.4 |   5.0  41.0  085   5  3   8.2   4.5
 10500   6.5  43.7  095   2  1   7.0   3.8 |   6.2  43.2  075   5  2   7.4   4.1
 10250   7.1  44.8  095   2  1  12.1   6.6 |   6.8  44.2  070   5  2  10.8   5.9
 10000   8.2  46.8  095   1  1  12.9   7.1 |   7.7  45.9  055   5  2  10.7   5.9
  9750   8.9  48.0  095   1  1   8.3   4.6 |   8.3  46.9  040   5  2   7.2   4.0
  9500   9.6  49.3  095   1  0   9.5   5.2 |   9.0  48.2  025   5  2   8.3   4.6
  9250  10.3  50.5  100   1  0   9.4   5.2 |   9.6  49.3  015   5  3   7.4   4.1
  9000  11.0  51.8  000   0  0   9.8   5.4 |  10.1  50.2  005   5  3   7.4   4.0
  8750  11.7  53.1  000   0  0   9.9   5.4 |  10.7  51.3  355   6  3   7.9   4.3
  8500  12.4  54.3  000   0  0   9.5   5.2 |  11.3  52.3  345   6  3   7.7   4.2
  8250  13.2  55.8  000   0  0  10.9   6.0 |  11.9  53.4  335   6  3   8.0   4.4
  8000  14.0  57.2  000   0  0  10.9   6.0 |  12.6  54.7  325   7  4   7.7   4.3
  7750  14.7  58.5  000   0  0   9.1   5.0 |  13.1  55.6  320   8  4   7.0   3.8
  7500  15.4  59.7  265   1  0   9.3   5.1 |  13.7  56.7  315   9  4   6.8   3.7
  7250  16.1  61.0  270   1  0   9.9   5.4 |  14.1  57.4  310   9  5   6.1   3.3
  7000  16.9  62.4  270   1  0  10.2   5.6 |  14.5  58.1  305  10  5   5.6   3.1
  6750  17.6  63.7  270   1  0   9.4   5.2 |  14.9  58.8  300  11  6   5.3   2.9
  6500  18.3  64.9  270   1  0   9.9   5.4 |  15.2  59.4  295  12  6   6.5   3.6
  6250  19.1  66.4  275   1  0  11.1   6.1 |  15.7  60.3  295  11  6   8.6   4.7
  6000  19.9  67.8  275   1  1  11.2   6.1 |  16.2  61.2  295  11  6   8.8   4.8
  5750  20.7  69.3  275   1  1  10.5   5.8 |  16.8  62.2  295  10  5   9.5   5.2
  5500  21.6  70.9  270   1  1  14.5   8.0 |  17.6  63.7  295  10  5  12.7   7.0
________________________________________________________________________________

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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