Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301231
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0631 MDT Saturday, May 30, 2015

This forecast is for Saturday, May 30, 2015:

If the trigger temperature of 62.2 F/16.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 784 ft/min (4.0 m/s)
   Maximum height of thermals.................. 15066 ft MSL (9781 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11715 ft MSL (6430 ft AGL)
Thermal soaring outlook for Sunday 05/31....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 15390 ft MSL (10105 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 35107 ft MSL (29822 ft AGL)
Wave soaring outlook for Sunday 05/31.......... Poor

Remarks...

Sunrise/Sunset.................... 05:34:37 / 20:19:14 MDT
Total possible sunshine........... 14 hr 44 min 37 sec (884 min 37 sec)
Altitude of sun at 12:57:07 MDT... 72.01 degrees

Upper air data from rawinsonde observation taken on 05/30/2015 at 0600 MDT

Freezing level.................. 12132 ft MSL (6847 ft AGL)
Convective condensation level... 12926 ft MSL (7641 ft AGL)
Lifted condensation level....... 13809 ft MSL (8523 ft AGL)
Lifted index.................... -2.6
K index......................... +13.9

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  -61.8 -79.2   300   22   11   1.8   1.0   94.5 202.0    40.9      M    M
 45000  -57.9 -72.2   300   18   10   4.1   2.3   76.3 169.4    32.7      M    M
 40000  -56.7 -70.1   315   33   17   1.1   0.6   55.4 131.7    21.1      M    M
 38000  -57.4 -71.3   340   36   19   2.3   1.3   45.5 113.9    15.0      M    M
 36000  -54.3 -65.7   350   44   23   5.9   3.3   41.4 106.6    12.6      M    M
 34000  -49.9 -57.8   355   47   24   7.8   4.3   39.2 102.6    11.4      M    M
 32000  -44.6 -48.3   355   43   22   7.8   4.3   37.5  99.6    10.5      M    M
 30000  -41.5 -42.7   350   32   16   4.1   2.2   34.0  93.2     8.0      M    M
 29000  -39.6 -39.3   345   29   15   7.5   4.1   32.6  90.8     7.1      M    M
 28000  -37.1 -34.8   345   26   14   9.2   5.0   32.1  89.7     6.8      M    M
 27000  -34.4 -29.9   340   24   12   9.2   5.0   31.9  89.4     6.7      M    M
 26000  -31.6 -24.9   335   24   12   9.2   5.0   31.6  88.8     6.5      M    M
 25000  -28.9 -20.0   335   24   12   9.2   5.0   31.4  88.5     6.5      M    M
 24000  -26.1 -15.0   335   23   12   9.4   5.1   31.1  88.1     6.3      M    M
 23000  -23.5 -10.3   330   23   12   7.4   4.1   30.8  87.4     6.1      M    M
 22000  -21.2  -6.2   330   23   12   7.5   4.1   29.9  85.9     5.5      M    M
 21000  -18.9  -2.0   325   24   12   9.0   5.0   29.3  84.8     5.0      M    M
 20000  -16.2   2.8   325   24   12   8.1   4.5   29.1  84.4     4.8      M    M
 19500  -15.3   4.5   325   22   11   5.1   2.8   28.4  83.2     4.3      M    M
 19000  -14.5   5.9   330   20   10   7.7   4.2   27.7  81.9     3.7      M    M
 18500  -13.4   7.9   330   20   10   5.4   3.0   27.4  81.2     3.4      M    M
 18000  -12.4   9.7   330   19   10   7.9   4.3   26.8  80.2     2.9      M    M
 17500  -11.2  11.8   330   19   10   7.8   4.3   26.4  79.6     2.6      M    M
 17000  -10.1  13.8   335   19   10   7.9   4.3   26.1  79.0     2.3      M    M
 16500   -9.0  15.8   335   18    9   6.3   3.5   25.7  78.3     1.9      M    M
 16000   -7.4  18.7   335   18    9   9.4   5.2   25.1  77.1     1.3      M    M
 15500   -6.9  19.6   335   17    9   1.5   0.8   24.0  75.3     0.4      M    M
 15000   -6.0  21.2   330   17    9   6.1   3.4   23.4  74.2    -0.2    769  3.9
 14500   -5.0  23.0   330   16    8   6.3   3.4   22.9  73.2    -0.7    726  3.7
 14000   -4.0  24.8   330   16    8   8.1   4.4   22.5  72.4    -1.1    680  3.5
 13500   -2.8  27.0   330   14    7   8.0   4.4   22.2  71.9    -1.4    630  3.2
 13000   -1.6  29.1   335   12    6   8.1   4.5   21.9  71.4    -1.7    579  2.9
 12500   -0.5  31.1   335   10    5   6.3   3.4   21.5  70.8    -2.1    531  2.7
 12000    0.3  32.5   340    9    5   5.8   3.2   20.9  69.6    -2.7    491  2.5
 11500    1.2  34.2   340    7    4   4.4   2.4   20.3  68.5    -3.3    451  2.3
 11000    1.5  34.7   345    5    3   2.8   1.6   19.1  66.5    -4.5    427  2.2
 10500    2.5  36.5   350    3    2   9.8   5.4   18.7  65.7    -5.0    382  1.9
 10250    3.1  37.6   335    2    1   6.9   3.8   18.6  65.4    -5.2    358  1.8
 10000    3.5  38.3   275    2    1   6.4   3.5   18.3  65.0    -5.5    336  1.7
  9750    4.0  39.2   245    4    2   6.6   3.6   18.1  64.5    -5.7    315  1.6
  9500    4.5  40.1   235    6    3   6.3   3.5   17.8  64.1    -6.0    293  1.5
  9250    4.8  40.6   230    8    4   3.9   2.1   17.5  63.5    -6.4    274  1.4
  9000    5.0  41.0   225   10    5   2.3   1.3   16.9  62.5    -7.0    262  1.3
  8750    5.2  41.4   220   10    5   2.8   1.5   16.4  61.5    -7.6    250  1.3
  8500    5.3  41.5   215   10    5   2.7   1.5   15.8  60.5    -8.2    238  1.2
  8250    5.5  41.9   210   11    5   2.8   1.6   15.3  59.5    -8.7    225  1.1
  8000    5.6  42.1   205   11    6   2.5   1.4   14.7  58.5    -9.3    213  1.1
  7750    5.8  42.4   200    9    5   4.5   2.5   14.2  57.6    -9.9    200  1.0
  7500    6.3  43.3   185    7    4   6.3   3.5   13.9  57.1   -10.2    179  0.9
  7250    6.8  44.2   170    6    3   5.8   3.2   13.6  56.5   -10.5    158  0.8
  7000    7.2  45.0   145    5    3   6.0   3.3   13.3  56.0   -10.8    136  0.7
  6750    7.7  45.9   155    5    2   6.0   3.3   13.1  55.5   -11.1    115  0.6
  6500    8.1  46.6   160    5    2   6.3   3.4   12.8  55.0   -11.4     94  0.5
  6250    8.6  47.5   170    5    2   7.3   4.0   12.5  54.6   -11.7     73  0.4
  6000    9.0  48.2   180    5    3   3.9   2.1   12.3  54.1   -12.0     53  0.3
  5750    9.1  48.4   165    3    2   1.7   0.9   11.7  53.0   -12.7     44  0.2
  5500    9.2  48.6   115    2    1  -0.6  -0.3   11.1  51.9   -13.4     34  0.2

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

           05/30/2015 at 0900 MDT          |       05/30/2015 at 1200 MDT
                                           |
K index... +11.8  LI... +274.3             | K index... +5.1  LI... +272.7
CAPE... 0.0  CIN... M                      | CAPE... +68.6  CIN... -59.1
                                           |
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 -59.5 -75.1  295  16  8   1.7   0.9 | -60.1 -76.2  295  17  9   1.4   0.8
 45000 -57.6 -71.7  315  23 12  -1.9  -1.0 | -58.6 -73.5  315  24 12  -2.2  -1.2
 40000 -60.6 -77.1  345  41 21  -2.7  -1.5 | -62.3 -80.1  340  46 24  -0.6  -0.3
 38000 -57.1 -70.8  350  43 22   6.9   3.8 | -57.7 -71.9  340  44 22   8.3   4.6
 36000 -53.0 -63.4  350  43 22   6.9   3.8 | -52.7 -62.9  340  40 21   8.3   4.6
 34000 -48.5 -55.3  350  41 21   7.9   4.3 | -47.9 -54.2  345  37 19   7.9   4.4
 32000 -43.8 -46.8  350  37 19   7.9   4.3 | -43.1 -45.6  345  35 18   7.9   4.4
 30000 -39.1 -38.4  350  33 17   7.9   4.3 | -38.4 -37.1  340  32 17   7.9   4.4
 29000 -36.7 -34.1  350  31 16   7.9   4.3 | -36.0 -32.8  340  31 16   7.9   4.4
 28000 -33.8 -28.8  350  28 15   7.9   4.4 | -33.0 -27.4  340  29 15   8.0   4.4
 27000 -31.6 -24.9  350  26 14   7.0   3.8 | -30.7 -23.3  340  27 14   7.8   4.3
 26000 -29.5 -21.1  345  24 13   7.0   3.8 | -28.3 -18.9  345  25 13   7.8   4.3
 25000 -27.5 -17.5  340  23 12   7.0   3.8 | -26.0 -14.8  345  23 12   7.8   4.3
 24000 -25.2 -13.4  340  22 11   8.0   4.4 | -23.8 -10.8  345  21 11   7.3   4.0
 23000 -22.8  -9.0  335  22 11   8.1   4.4 | -21.6  -6.9  345  20 10   7.3   4.0
 22000 -20.4  -4.7  335  21 11   8.1   4.4 | -19.4  -2.9  340  19 10   7.3   4.0
 21000 -18.0  -0.4  335  21 11   7.8   4.3 | -17.2   1.0  335  18  9   7.7   4.2
 20000 -15.7   3.7  335  20 10   7.8   4.3 | -14.9   5.2  330  16  8   7.7   4.2
 19500 -14.5   5.9  335  19 10   7.8   4.3 | -13.8   7.2  330  16  8   7.7   4.2
 19000 -13.4   7.9  335  19 10   7.6   4.2 | -12.6   9.3  330  15  8   7.4   4.1
 18500 -12.3   9.9  335  18  9   7.3   4.0 | -11.5  11.3  325  15  8   7.2   4.0
 18000 -11.2  11.8  335  17  9   7.4   4.1 | -10.5  13.1  325  15  8   7.3   4.0
 17500 -10.2  13.6  335  16  8   6.5   3.6 |  -9.5  14.9  325  14  7   6.2   3.4
 17000  -9.2  15.4  335  15  8   6.6   3.6 |  -8.5  16.7  320  14  7   6.3   3.4
 16500  -8.3  17.1  335  14  7   6.6   3.6 |  -7.6  18.3  320  13  7   6.6   3.6
 16000  -7.3  18.9  335  14  7   6.6   3.6 |  -6.6  20.1  315  13  7   6.7   3.7
 15500  -6.4  20.5  335  13  7   6.6   3.6 |  -5.6  21.9  315  13  7   6.9   3.8
 15000  -4.9  23.2  335  12  6   6.8   3.7 |  -4.0  24.8  310  13  7   7.3   4.0
 14500  -3.9  25.0  335  12  6   6.9   3.8 |  -3.0  26.6  310  13  7   7.3   4.0
 14000  -2.9  26.8  330  12  6   6.9   3.8 |  -1.9  28.6  310  13  7   7.3   4.0
 13500  -1.9  28.6  330  11  6   6.8   3.7 |  -0.9  30.4  305  13  7   7.4   4.1
 13000  -1.0  30.2  325  11  6   6.5   3.6 |   0.2  32.4  305  13  7   7.5   4.1
 12500  -0.1  31.8  325  11  5   6.7   3.7 |   1.3  34.3  305  13  6   7.4   4.1
 12000   0.8  33.4  325   9  5   7.0   3.8 |   2.3  36.1  305  12  6   7.0   3.8
 11500   1.8  35.2  325   8  4   7.0   3.8 |   3.3  37.9  305  11  6   7.0   3.9
 11000   2.8  37.0  325   6  3   7.0   3.8 |   4.3  39.7  300  10  5   6.9   3.8
 10500   3.9  39.0  325   5  2   5.7   3.1 |   5.3  41.5  300   8  4   5.1   2.8
 10250   4.2  39.6  325   4  2   2.6   1.4 |   5.6  42.1  300   8  4   3.3   1.8
 10000   4.4  39.9  325   4  2   5.3   2.9 |   5.9  42.6  295   7  4   7.3   4.0
  9750   4.9  40.8  320   4  2   8.3   4.5 |   6.6  43.9  295   6  3   9.9   5.4
  9500   5.5  41.9  310   4  2   5.9   3.2 |   7.2  45.0  295   5  3   7.2   4.0
  9250   5.7  42.3  305   4  2   3.4   1.9 |   7.6  45.7  295   4  2   4.3   2.4
  9000   6.0  42.8  295   3  2   4.2   2.3 |   7.9  46.2  295   4  2   5.2   2.8
  8750   6.3  43.3  275   3  1   5.9   3.2 |   8.3  46.9  280   2  1   6.0   3.3
  8500   6.7  44.1  250   3  1   4.6   2.5 |   8.7  47.7  185   1  0   5.8   3.2
  8250   6.9  44.4  225   3  2   3.2   1.8 |   9.1  48.4  140   1  1   5.6   3.1
  8000   7.2  45.0  210   4  2   3.8   2.1 |   9.4  48.9  125   2  1   6.3   3.5
  7750   7.4  45.3  200   5  3   4.7   2.6 |   9.8  49.6  115   3  2   8.3   4.5
  7500   7.8  46.0  190   5  3   5.2   2.8 |  10.4  50.7  110   3  2   9.7   5.3
  7250   8.1  46.6  180   5  3   5.4   3.0 |  11.1  52.0  110   3  2   9.8   5.4
  7000   8.5  47.3  165   5  2   4.0   2.2 |  11.9  53.4  110   3  2   9.9   5.4
  6750   8.8  47.8  150   5  2   6.4   3.5 |  12.6  54.7  105   3  2  10.4   5.7
  6500   9.4  48.9  140   4  2  10.2   5.6 |  13.4  56.1  105   3  2  10.7   5.9
  6250  10.1  50.2  135   4  2   9.5   5.2 |  14.2  57.6  105   3  2  10.5   5.8
  6000  10.8  51.4  125   3  2  10.5   5.7 |  15.0  59.0  100   3  2  10.9   6.0
  5750  11.7  53.1  120   3  2  14.6   8.0 |  15.9  60.6  100   3  2  17.4   9.5
  5500  13.0  55.4  115   3  2  19.0  10.4 |  17.6  63.7  095   3  2  26.8  14.7

           05/30/2015 at 1500 MDT          |       05/30/2015 at 1800 MDT
                                           |
K index... +13.9  LI... +271.3             | K index... +25.2  LI... +270.8
CAPE... +250.7  CIN... -44.7               | CAPE... +378.8  CIN... -18.3
                                           |
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 -60.7 -77.3  300  18  9   0.8   0.4 | -61.8 -79.2  305  18  9  -0.0  -0.0
 45000 -59.9 -75.8  315  27 14  -1.3  -0.7 | -61.7 -79.1  315  29 15   0.4   0.2
 40000 -62.0 -79.6  340  48 25   0.9   0.5 | -61.1 -78.0  325  46 23   3.2   1.7
 38000 -57.3 -71.1  335  46 23   8.3   4.5 | -56.6 -69.9  330  45 23   7.7   4.2
 36000 -52.4 -62.3  335  42 22   8.3   4.5 | -52.0 -61.6  335  45 23   7.7   4.2
 34000 -47.5 -53.5  335  40 20   7.9   4.3 | -47.2 -53.0  335  43 22   8.2   4.5
 32000 -42.8 -45.0  335  38 20   7.9   4.3 | -42.3 -44.1  330  39 20   8.1   4.5
 30000 -37.3 -35.1  340  33 17   8.3   4.6 | -37.3 -35.1  330  33 17   8.4   4.6
 29000 -34.8 -30.6  340  30 16   8.3   4.6 | -34.2 -29.6  330  28 14   8.4   4.6
 28000 -32.3 -26.1  340  28 14   8.4   4.6 | -31.7 -25.1  330  24 12   8.4   4.6
 27000 -30.0 -22.0  340  25 13   7.6   4.2 | -29.2 -20.6  325  23 12   8.2   4.5
 26000 -27.7 -17.9  335  22 11   7.6   4.2 | -26.8 -16.2  320  23 12   8.2   4.5
 25000 -25.4 -13.7  335  20 10   7.6   4.2 | -24.3 -11.7  320  23 12   8.2   4.5
 24000 -23.2  -9.8  330  18  9   7.3   4.0 | -22.0  -7.6  315  22 12   7.3   4.0
 23000 -21.0  -5.8  320  17  9   7.3   4.0 | -19.8  -3.6  310  22 11   7.3   4.0
 22000 -18.8  -1.8  315  16  8   7.4   4.1 | -17.6   0.3  305  22 11   7.4   4.0
 21000 -16.7   1.9  310  16  8   6.9   3.8 | -15.7   3.7  300  22 12   6.4   3.5
 20000 -14.7   5.5  305  16  8   6.9   3.8 | -13.7   7.3  295  24 12   6.5   3.6
 19500 -13.7   7.3  300  17  9   6.9   3.8 | -12.8   9.0  290  24 12   6.5   3.6
 19000 -12.6   9.3  300  17  9   7.1   3.9 | -11.8  10.8  290  25 13   6.9   3.8
 18500 -11.5  11.3  295  18  9   7.3   4.0 | -10.8  12.6  290  26 13   7.2   4.0
 18000 -10.5  13.1  295  18  9   7.3   4.0 |  -9.7  14.5  285  26 14   7.3   4.0
 17500  -9.3  15.3  295  19 10   7.6   4.2 |  -8.6  16.5  285  26 14   8.4   4.6
 17000  -8.2  17.2  290  19 10   7.6   4.2 |  -7.4  18.7  290  26 13   8.5   4.6
 16500  -7.1  19.2  290  20 10   7.7   4.2 |  -6.3  20.7  290  26 13   8.1   4.5
 16000  -6.0  21.2  290  20 10   7.8   4.3 |  -5.1  22.8  290  24 12   8.0   4.4
 15500  -4.2  24.4  290  21 11   8.5   4.7 |  -3.4  25.9  290  22 11   7.5   4.1
 15000  -3.0  26.6  295  20 10   8.5   4.7 |  -2.3  27.9  290  19 10   7.5   4.1
 14500  -1.8  28.8  295  20 10   8.1   4.5 |  -1.3  29.7  285  17  9   7.2   3.9
 14000  -0.6  30.9  300  19 10   7.9   4.4 |  -0.3  31.5  285  14  7   7.0   3.8
 13500   0.5  32.9  300  18  9   7.8   4.3 |   0.7  33.3  275  11  6   6.9   3.8
 13000   1.6  34.9  300  16  8   7.7   4.2 |   1.7  35.1  260   9  5   6.7   3.7
 12500   2.6  36.7  305  15  7   7.5   4.1 |   2.6  36.7  235   8  4   6.5   3.6
 12000   3.6  38.5  305  12  6   7.0   3.8 |   3.5  38.3  205   8  4   6.1   3.3
 11500   4.6  40.3  305   9  5   6.8   3.7 |   4.3  39.7  185  11  5   6.6   3.6
 11000   5.6  42.1  305   6  3   5.9   3.2 |   5.4  41.7  170  11  6   8.5   4.6
 10500   6.5  43.7  300   2  1   4.1   2.2 |   6.7  44.1  160  11  5   5.6   3.1
 10250   6.7  44.1  295   1  1   3.5   1.9 |   7.0  44.6  160  11  5   6.0   3.3
 10000   7.1  44.8  000   0  0   7.6   4.2 |   7.7  45.9  160  11  5  11.6   6.4
  9750   7.6  45.7  125   3  1   8.8   4.8 |   8.5  47.3  155  10  5  12.3   6.8
  9500   8.1  46.6  125   5  3   8.0   4.4 |   9.4  48.9  155  10  5  10.5   5.7
  9250   8.6  47.5  125   6  3   6.6   3.6 |  10.0  50.0  155  10  5   7.4   4.0
  9000   9.1  48.4  125   6  3   9.5   5.2 |  10.6  51.1  155  10  5   9.7   5.3
  8750  10.0  50.0  120   6  3  12.6   6.9 |  11.5  52.7  155  10  5  12.3   6.8
  8500  10.8  51.4  120   6  3  10.3   5.6 |  12.3  54.1  155  10  5  10.5   5.8
  8250  11.5  52.7  120   6  3   8.8   4.8 |  13.1  55.6  155  10  5   9.2   5.1
  8000  12.2  54.0  120   6  3   9.6   5.2 |  13.8  56.8  155  10  5   9.7   5.3
  7750  12.9  55.2  120   6  3  10.2   5.6 |  14.5  58.1  150   9  5  10.3   5.6
  7500  13.7  56.7  120   6  3  10.3   5.7 |  15.3  59.5  150   9  5  10.1   5.5
  7250  14.5  58.1  120   6  3  10.1   5.6 |  16.0  60.8  150   9  5   9.9   5.4
  7000  15.2  59.4  120   5  3  10.5   5.8 |  16.8  62.2  150   9  5  10.0   5.5
  6750  16.0  60.8  115   5  3  10.7   5.8 |  17.5  63.5  150   9  4  10.0   5.5
  6500  16.8  62.2  115   5  3  10.2   5.6 |  18.2  64.8  150   8  4  10.1   5.6
  6250  17.5  63.5  115   5  3   9.8   5.4 |  19.0  66.2  150   8  4  10.2   5.6
  6000  18.3  64.9  115   5  3  10.8   5.9 |  19.7  67.5  150   8  4   9.8   5.4
  5750  19.2  66.6  115   5  3  17.5   9.6 |  20.5  68.9  150   8  4  12.2   6.7
  5500  20.8  69.4  115   5  3  25.7  14.1 |  21.6  70.9  145   7  4  17.4   9.6
________________________________________________________________________________

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

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

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

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

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

DEFINITIONS:

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

042613


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