Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 011250
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0650 MDT Saturday, August 1, 2015

This forecast is for Saturday, August 1, 2015:

If the trigger temperature of 84.0 F/28.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1554 ft/min (7.9 m/s)
   Maximum height of thermals.................. 19362 ft MSL (14077 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1115 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................. 11522 ft MSL (6236 ft AGL)
Thermal soaring outlook for Sunday 08/02....... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... None
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 14374 ft MSL (9089 ft AGL)
Wave soaring outlook for Sunday 08/02.......... Poor

Remarks... None

Sunrise/Sunset.................... 05:58:17 / 20:13:39 MDT
Total possible sunshine........... 14 hr 15 min 22 sec (855 min 22 sec)
Altitude of sun at 13:05:44 MDT... 68.16 degrees

Upper air data from rawinsonde observation taken on 08/01/2015 at 0600 MDT

Freezing level.................. 16103 ft MSL (10818 ft AGL)
Convective condensation level... 15214 ft MSL (9929 ft AGL)
Lifted condensation level....... 15856 ft MSL (10571 ft AGL)
Lifted index.................... -2.9
K index......................... +27.1

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  -68.1 -90.6   280   31   16   7.3   4.0   78.7 173.6    26.4      M    M
 45000  -63.1 -81.6   265   52   27   3.0   1.7   62.6 144.7    18.3      M    M
 40000  -51.5 -60.7   275   50   26   7.8   4.3   56.8 134.2    15.8      M    M
 38000  -47.0 -52.6   280   45   23   7.6   4.2   54.8 130.7    14.8      M    M
 36000  -42.0 -43.6   280   39   20   9.5   5.2   53.6 128.5    14.3      M    M
 34000  -36.5 -33.7   280   37   19   9.0   4.9   53.0 127.4    14.3      M    M
 32000  -32.3 -26.1   285   35   18   8.7   4.8   50.8 123.5    13.0      M    M
 30000  -27.9 -18.2   285   29   15   2.3   1.2   49.1 120.3    12.0      M    M
 29000  -26.1 -15.0   285   29   15   8.4   4.6   47.6 117.7    11.0      M    M
 28000  -23.7 -10.7   280   29   15   6.2   3.4   46.1 114.9     9.9      M    M
 27000  -21.7  -7.1   280   28   15   6.3   3.5   44.9 112.9     9.1      M    M
 26000  -20.0  -4.0   290   23   12   5.9   3.2   43.5 110.3     8.0      M    M
 25000  -18.1  -0.6   300   18    9   8.2   4.5   42.3 108.1     7.0      M    M
 24000  -15.6   3.9   290   15    8   7.4   4.1   41.8 107.2     6.6      M    M
 23000  -13.3   8.1   280   13    7   7.8   4.3   40.9 105.6     6.1      M    M
 22000  -11.5  11.3   265   12    6   6.8   3.7   39.4 103.0     5.1      M    M
 21000   -9.4  15.1   285    8    4   6.8   3.7   38.4 101.1     4.3      M    M
 20000   -8.2  17.2   305   13    7  -1.7  -0.9   36.6  97.9     2.7      M    M
 19500   -8.9  16.0   305   15    8  -2.5  -1.4   34.4  93.9     0.5      M    M
 19000   -8.1  17.4   305   20   10  10.2   5.6   33.6  92.5    -0.2   1323  6.7
 18500   -6.7  19.9   305   18    9   9.4   5.1   33.6  92.4    -0.3   1267  6.4
 18000   -5.4  22.3   305   16    8   9.3   5.1   33.5  92.3    -0.4   1211  6.2
 17500   -4.0  24.8   310   14    7   9.3   5.1   33.4  92.1    -0.5   1155  5.9
 17000   -2.6  27.3   315   13    7   9.3   5.1   33.3  92.0    -0.6   1099  5.6
 16500   -1.2  29.8   325   11    6   9.0   5.0   33.2  91.8    -0.6   1043  5.3
 16000    0.0  32.0   335   10    5   8.7   4.8   33.1  91.5    -0.8    991  5.0
 15500    1.2  34.2   335    7    3   8.8   4.8   32.9  91.2    -1.1    939  4.8
 15000    2.5  36.5   325    3    1   8.8   4.8   32.7  90.9    -1.3    888  4.5
 14500    3.7  38.7   210    2    1   8.9   4.9   32.6  90.7    -1.5    835  4.2
 14000    5.7  42.3   180    6    3   8.9   4.9   32.4  90.3    -1.7    753  3.8
 13500    7.0  44.6   190    7    4   8.5   4.7   32.2  90.0    -1.9    699  3.6
 13000    8.2  46.8   195    8    4   8.2   4.5   32.0  89.6    -2.2    649  3.3
 12500    9.4  48.9   195    9    5   8.2   4.5   31.7  89.1    -2.5    599  3.0
 12000   10.6  51.1   200   10    5   8.2   4.5   31.5  88.7    -2.7    549  2.8
 11500   11.7  53.1   190   11    5   8.2   4.5   31.2  88.2    -3.1    499  2.5
 11000   12.9  55.2   185   11    6   8.2   4.5   31.0  87.7    -3.4    449  2.3
 10500   14.1  57.4   180   12    6   8.3   4.5   30.7  87.3    -3.6    399  2.0
 10250   14.7  58.5   175   12    6   8.3   4.6   30.6  87.1    -3.8    374  1.9
 10000   15.3  59.5   170   11    6   8.3   4.6   30.5  86.9    -3.9    348  1.8
  9750   15.9  60.6   160   11    6   8.3   4.6   30.4  86.7    -4.0    322  1.6
  9500   16.5  61.7   155   12    6   8.3   4.6   30.3  86.5    -4.2    297  1.5
  9250   17.1  62.8   150   12    6   8.3   4.6   30.2  86.3    -4.3    271  1.4
  9000   17.7  63.9   145   12    6   8.3   4.6   30.1  86.1    -4.4    246  1.2
  8750   18.3  64.9   150   10    5   8.3   4.6   30.0  85.9    -4.6    220  1.1
  8500   18.9  66.0   155    8    4   8.2   4.5   29.8  85.7    -4.7    195  1.0
  8250   19.5  67.1   160    6    3   6.5   3.6   29.7  85.4    -4.9    171  0.9
  8000   19.9  67.8   175    5    3   5.1   2.8   29.4  84.8    -5.2    152  0.8
  7750   20.3  68.5   180    7    3   6.4   3.5   29.0  84.3    -5.6    133  0.7
  7500   20.7  69.3   185    8    4   2.8   1.5   28.7  83.7    -5.9    113  0.6
  7250   20.6  69.1   190   10    5  -4.9  -2.7   27.9  82.2    -6.8    110  0.6
  7000   20.2  68.4   190   12    6  -0.5  -0.2   26.8  80.2    -7.9    112  0.6
  6750   20.5  68.9   195   13    7   5.2   2.8   26.3  79.4    -8.4     98  0.5
  6500   20.7  69.3   195   14    7   2.9   1.6   25.9  78.6    -8.9     83  0.4
  6250   21.0  69.8   200   16    8   6.5   3.6   25.4  77.8    -9.4     68  0.3
  6000   21.1  70.0   200   17    9  -8.7  -4.8   24.9  76.9    -9.9     55  0.3
  5750   19.9  67.8   200   13    7 -11.7  -6.4   23.0  73.4   -11.9     85  0.4
  5500   20.1  68.2   195    9    5  17.9   9.8   22.5  72.6   -12.5     73  0.4

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

           08/01/2015 at 0900 MDT          |       08/01/2015 at 1200 MDT
                                           |
K index... +25.3  LI... -3.3               | K index... +26.0  LI... -4.7
CAPE... +288.3  CIN... -135.7              | CAPE... +787.5  CIN... -32.7
                                           |
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 -67.0 -88.6  290  32 17   1.2   0.6 | -66.8 -88.2  280  35 18   1.2   0.6
 45000 -62.6 -80.7  285  46 24   6.7   3.7 | -62.4 -80.3  280  47 24   6.5   3.6
 40000 -51.7 -61.1  280  49 25   8.2   4.5 | -51.7 -61.1  275  46 24   8.0   4.4
 38000 -46.7 -52.1  280  45 23   8.2   4.5 | -46.8 -52.2  275  44 22   8.0   4.4
 36000 -41.8 -43.2  280  42 22   8.0   4.4 | -42.0 -43.6  275  41 21   8.3   4.6
 34000 -37.1 -34.8  280  39 20   7.8   4.3 | -36.9 -34.4  275  38 20   8.5   4.7
 32000 -32.4 -26.3  280  35 18   8.5   4.7 | -31.8 -25.2  275  36 18   9.3   5.1
 30000 -28.0 -18.4  280  30 16   7.4   4.0 | -27.4 -17.3  280  30 16   7.2   4.0
 29000 -25.2 -13.4  280  27 14   7.4   4.0 | -24.7 -12.5  280  27 14   7.2   4.0
 28000 -23.1  -9.6  280  25 13   6.3   3.5 | -22.6  -8.7  280  24 13   6.2   3.4
 27000 -21.2  -6.2  280  22 11   6.4   3.5 | -20.7  -5.3  280  23 12   6.3   3.4
 26000 -19.3  -2.7  280  20 10   6.4   3.5 | -18.9  -2.0  280  21 11   6.3   3.5
 25000 -17.4   0.7  280  17  9   6.4   3.5 | -17.0   1.4  280  19 10   6.4   3.5
 24000 -15.5   4.1  285  16  8   6.3   3.5 | -15.1   4.8  285  18  9   6.5   3.6
 23000 -13.7   7.3  290  15  8   6.3   3.5 | -13.2   8.2  285  16  8   6.5   3.6
 22000 -11.8  10.8  295  14  7   5.6   3.1 | -11.2  11.8  290  15  8   5.4   3.0
 21000 -10.3  13.5  305  13  7   5.3   2.9 |  -9.8  14.4  295  14  7   4.9   2.7
 20000  -8.9  16.0  315  13  6   5.5   3.0 |  -8.4  16.9  305  12  6   5.0   2.7
 19500  -8.1  17.4  320  13  6   5.8   3.2 |  -7.7  18.1  310  12  6   5.2   2.8
 19000  -7.1  19.2  320  12  6   8.5   4.6 |  -6.8  19.8  310  12  6   6.9   3.8
 18500  -5.9  21.4  325  11  6   8.4   4.6 |  -5.8  21.6  310  13  7   6.9   3.8
 18000  -4.8  23.4  325  10  5   8.2   4.5 |  -4.8  23.4  315  13  7   8.6   4.7
 17500  -3.6  25.5  325   8  4   8.1   4.4 |  -3.5  25.7  330  11  6   9.2   5.1
 17000  -2.5  27.5  325   6  3   8.0   4.4 |  -2.1  28.2  345  11  6   9.2   5.0
 16500  -1.5  29.3  320   4  2   6.2   3.4 |  -0.9  30.4  350  10  5   8.0   4.4
 16000  -0.5  31.1  310   3  1   6.1   3.4 |   0.2  32.4  350   8  4   8.1   4.4
 15500   0.6  33.1  285   2  1   8.8   4.8 |   2.0  35.6  350   6  3   8.5   4.7
 15000   2.6  36.7  255   2  1   9.2   5.0 |   3.2  37.8  350   5  3   8.5   4.6
 14500   3.9  39.0  240   3  1   8.8   4.8 |   4.4  39.9  345   4  2   9.0   4.9
 14000   5.2  41.4  230   4  2   8.9   4.9 |   5.8  42.4  335   3  2   9.0   4.9
 13500   6.5  43.7  225   4  2   8.7   4.8 |   7.1  44.8  320   3  2   8.5   4.7
 13000   7.8  46.0  215   5  3   8.6   4.7 |   8.3  46.9  300   3  1   8.5   4.6
 12500   9.2  48.6  215   6  3   8.4   4.6 |   9.6  49.3  280   3  1   8.5   4.7
 12000  10.5  50.9  210   7  4   8.4   4.6 |  10.8  51.4  270   3  2   8.5   4.7
 11500  11.8  53.2  205   7  4   8.2   4.5 |  12.1  53.8  255   3  2   8.2   4.5
 11000  13.0  55.4  200   8  4   7.8   4.3 |  13.3  55.9  250   3  2   7.7   4.2
 10500  14.2  57.6  195   8  4   4.2   2.3 |  14.5  58.1  240   3  2   3.9   2.2
 10250  14.4  57.9  195   8  4   5.3   2.9 |  14.6  58.3  240   3  2   4.6   2.5
 10000  15.0  59.0  190   8  4  10.7   5.9 |  15.2  59.4  230   3  1  10.0   5.5
  9750  15.6  60.1  190   8  4  10.0   5.5 |  15.8  60.4  220   3  2   9.1   5.0
  9500  16.3  61.3  190   8  4   7.9   4.3 |  16.4  61.5  210   3  2   7.5   4.1
  9250  16.6  61.9  190   8  4   5.7   3.1 |  16.8  62.2  195   3  2   6.4   3.5
  9000  17.0  62.6  190   8  4   7.8   4.3 |  17.3  63.1  185   3  2   8.8   4.8
  8750  17.5  63.5  190   8  4   8.3   4.6 |  17.9  64.2  170   3  2   9.3   5.1
  8500  18.1  64.6  190   8  4   8.0   4.4 |  18.5  65.3  160   3  2   8.8   4.8
  8250  18.6  65.5  190   8  4   7.9   4.3 |  19.1  66.4  155   3  2   8.1   4.5
  8000  19.2  66.6  190   8  4   7.8   4.3 |  19.7  67.5  150   3  2   9.2   5.1
  7750  19.8  67.6  195   8  4   7.2   3.9 |  20.4  68.7  150   3  2  10.2   5.6
  7500  20.3  68.5  195   8  4   5.9   3.3 |  21.1  70.0  145   3  2   9.9   5.4
  7250  20.6  69.1  195   8  4   5.0   2.7 |  21.8  71.2  145   3  2   9.8   5.4
  7000  21.0  69.8  195   9  4   6.3   3.4 |  22.6  72.7  145   3  2  10.1   5.5
  6750  21.4  70.5  200   9  5   4.8   2.6 |  23.3  73.9  145   3  2  10.8   5.9
  6500  21.6  70.9  200   8  4   1.3   0.7 |  24.2  75.6  145   3  1  10.8   5.9
  6250  21.6  70.9  200   7  4   0.0   0.0 |  25.0  77.0  145   3  1  11.4   6.3
  6000  21.6  70.9  195   6  3   2.9   1.6 |  25.8  78.4  145   3  1   8.7   4.8
  5750  22.1  71.8  200   5  2  10.9   6.0 |  26.5  79.7  140   3  1  13.8   7.6
  5500  23.1  73.6  200   4  2  15.9   8.7 |  28.1  82.6  140   3  1  30.2  16.6

           08/01/2015 at 1500 MDT          |       08/01/2015 at 1800 MDT
                                           |
K index... +22.0  LI... -3.6               | K index... +32.2  LI... -3.5
CAPE... +473.5  CIN... -4.9                | CAPE... +316.5  CIN... -1.6
                                           |
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 -66.6 -87.9  275  40 21   1.3   0.7 | -66.3 -87.3  280  42 21   1.1   0.6
 45000 -62.1 -79.8  275  53 27   6.3   3.4 | -62.2 -80.0  270  55 28   6.1   3.4
 40000 -51.6 -60.9  270  52 27   8.4   4.6 | -51.7 -61.1  260  53 27   8.9   4.9
 38000 -46.6 -51.9  265  49 25   8.4   4.6 | -46.4 -51.5  260  49 25   8.9   4.9
 36000 -41.6 -42.9  260  45 23   8.3   4.6 | -41.1 -42.0  260  45 23   8.5   4.7
 34000 -36.6 -33.9  265  42 22   8.2   4.5 | -36.2 -33.2  270  40 21   8.1   4.5
 32000 -31.7 -25.1  275  40 20   8.9   4.9 | -31.3 -24.3  280  36 19   9.1   5.0
 30000 -27.2 -17.0  275  33 17   7.4   4.1 | -27.0 -16.6  285  31 16   7.1   3.9
 29000 -24.4 -11.9  280  29 15   7.4   4.1 | -24.4 -11.9  295  28 14   7.1   3.9
 28000 -22.3  -8.1  280  26 14   6.0   3.3 | -22.4  -8.3  295  26 13   6.1   3.3
 27000 -20.5  -4.9  285  24 13   6.1   3.3 | -20.6  -5.1  300  24 12   6.2   3.4
 26000 -18.7  -1.7  285  23 12   6.1   3.3 | -18.8  -1.8  300  22 11   6.2   3.4
 25000 -16.9   1.6  290  21 11   6.4   3.5 | -16.9   1.6  305  21 11   6.2   3.4
 24000 -15.0   5.0  295  20 10   6.6   3.6 | -15.2   4.6  310  18  9   6.1   3.4
 23000 -13.1   8.4  300  19 10   6.6   3.6 | -13.4   7.9  320  16  8   6.2   3.4
 22000 -11.1  12.0  305  19 10   5.8   3.2 | -11.6  11.1  330  15  8   5.7   3.2
 21000  -9.5  14.9  315  17  9   5.3   2.9 | -10.0  14.0  340  15  8   5.4   2.9
 20000  -7.9  17.8  330  16  8   5.4   2.9 |  -8.4  16.9  350  16  8   5.4   2.9
 19500  -7.1  19.2  335  16  8   5.6   3.0 |  -7.6  18.3  355  16  8   5.4   3.0
 19000  -6.1  21.0  340  16  8   8.2   4.5 |  -6.6  20.1  360  16  8   8.3   4.6
 18500  -4.9  23.2  345  16  8   8.0   4.4 |  -5.4  22.3  005  15  8   8.1   4.4
 18000  -3.8  25.2  345  15  8   8.0   4.4 |  -4.2  24.4  005  14  7   7.5   4.1
 17500  -2.6  27.3  350  14  7   8.0   4.4 |  -3.2  26.2  010  12  6   7.1   3.9
 17000  -1.4  29.5  350  13  7   7.9   4.4 |  -2.2  28.0  020  10  5   7.1   3.9
 16500  -0.3  31.5  360  13  6   7.4   4.1 |  -1.2  29.8  030   7  4   6.8   3.7
 16000   0.8  33.4  010  12  6   7.4   4.1 |  -0.2  31.6  055   5  3   6.8   3.7
 15500   1.9  35.4  020  12  6   7.6   4.2 |   1.3  34.3  110   4  2   7.8   4.3
 15000   3.5  38.3  030  10  5   7.7   4.2 |   2.3  36.1  135   5  2   7.6   4.2
 14500   4.6  40.3  040   8  4   7.5   4.1 |   3.5  38.3  145   5  3   9.9   5.4
 14000   5.6  42.1  055   6  3   7.6   4.2 |   4.9  40.8  145   5  3   9.8   5.4
 13500   6.6  43.9  075   5  2   8.9   4.9 |   6.4  43.5  145   5  3   9.9   5.4
 13000   7.9  46.2  095   4  2   9.2   5.0 |   7.8  46.0  150   5  3   9.9   5.4
 12500   9.2  48.6  110   5  2   9.7   5.3 |   9.3  48.7  150   5  3   9.8   5.4
 12000  10.6  51.1  115   5  2  10.0   5.5 |  10.7  51.3  150   5  2   9.8   5.4
 11500  12.1  53.8  115   5  2   9.7   5.3 |  12.1  53.8  150   5  2   9.7   5.3
 11000  13.5  56.3  115   4  2   9.2   5.0 |  13.6  56.5  150   4  2   9.4   5.2
 10500  14.8  58.6  120   4  2   5.3   2.9 |  15.0  59.0  150   4  2   6.3   3.5
 10250  15.1  59.2  120   4  2   6.7   3.7 |  15.4  59.7  155   4  2   7.4   4.1
 10000  15.9  60.6  120   4  2  12.9   7.1 |  16.2  61.2  155   4  2  12.3   6.7
  9750  16.8  62.2  120   4  2  11.8   6.5 |  17.0  62.6  155   4  2  11.5   6.3
  9500  17.6  63.7  120   4  2  10.2   5.6 |  17.9  64.2  160   4  2   9.7   5.3
  9250  18.2  64.8  120   4  2   8.9   4.9 |  18.5  65.3  160   4  2   8.5   4.7
  9000  19.0  66.2  120   4  2  10.8   5.9 |  19.2  66.6  160   4  2  10.7   5.9
  8750  19.8  67.6  120   4  2  11.2   6.2 |  20.0  68.0  160   4  2  11.0   6.0
  8500  20.6  69.1  120   4  2  10.3   5.7 |  20.9  69.6  160   4  2  10.6   5.8
  8250  21.3  70.3  120   4  2   9.5   5.2 |  21.6  70.9  165   3  2  10.5   5.8
  8000  22.0  71.6  120   4  2   9.9   5.5 |  22.4  72.3  165   3  2   9.8   5.4
  7750  22.8  73.0  120   4  2  10.1   5.6 |  23.1  73.6  165   3  2   9.1   5.0
  7500  23.5  74.3  120   4  2  10.0   5.5 |  23.8  74.8  170   3  2   9.7   5.3
  7250  24.3  75.7  120   4  2  10.0   5.5 |  24.5  76.1  170   3  2  10.0   5.5
  7000  25.0  77.0  125   4  2   9.7   5.3 |  25.3  77.5  170   3  1  10.0   5.5
  6750  25.7  78.3  125   3  2   9.8   5.4 |  26.0  78.8  175   3  1  10.4   5.7
  6500  26.5  79.7  125   3  2  10.7   5.9 |  26.8  80.2  175   3  1  10.3   5.6
  6250  27.3  81.1  125   3  2  12.0   6.6 |  27.5  81.5  175   3  1  10.4   5.7
  6000  28.1  82.6  125   3  2   9.1   5.0 |  28.3  82.9  180   2  1   9.5   5.2
  5750  28.9  84.0  120   3  2  13.2   7.3 |  29.0  84.2  180   2  1  11.5   6.3
  5500  30.4  86.7  120   3  2  29.6  16.3 |  30.1  86.2  180   2  1  18.4  10.1
________________________________________________________________________________

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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