Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210121
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1921 MDT Thursday, July 20, 2017

This forecast is for Friday, July 21, 2017:

If the trigger temperature of 82.9 F/28.3 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 744 ft/min (3.8 m/s)
   Maximum height of thermals.................. 14289 ft MSL (8982 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1015 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................. 10682 ft MSL (5375 ft AGL)
Thermal soaring outlook for Saturday 07/22..... 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)................ Weak PVA
Potential height of wave....................... 22558 ft MSL (17251 ft AGL)
Wave soaring outlook for Saturday 07/22........ Poor

Remarks...

Sunrise/Sunset.................... 05:49:06 / 20:22:55 MDT
Total possible sunshine........... 14 hr 33 min 49 sec (873 min 49 sec)
Altitude of sun at 13:05:52 MDT... 70.52 degrees

Upper air data from numerical model forecast valid on 07/21/2017 at 0600 MDT

Freezing level.................. 17613 ft MSL (12306 ft AGL)
Convective condensation level... 17320 ft MSL (12013 ft AGL)
Lifted condensation level....... 15870 ft MSL (10563 ft AGL)
Lifted index.................... -1.2
K index......................... +23.7

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  -65.6 -86.1   255   21   11   2.8   1.5      M     M       M      M    M
 45000  -59.4 -74.9   240   25   13   6.3   3.5      M     M       M      M    M
 40000  -49.9 -57.8   220   27   14   6.6   3.6      M     M       M      M    M
 38000  -45.9 -50.6   220   18    9   6.6   3.6      M     M       M      M    M
 36000  -41.9 -43.4   215   10    5   7.3   4.0      M     M       M      M    M
 34000  -36.4 -33.5   235   13    7   8.3   4.5      M     M       M      M    M
 32000  -31.4 -24.5   250   17    9   8.7   4.8   51.0 123.8    13.5      M    M
 30000  -26.8 -16.2   240   20   10   7.8   4.3   49.2 120.5    12.4      M    M
 29000  -24.5 -12.1   240   21   11   7.8   4.3   48.5 119.3    12.0      M    M
 28000  -22.3  -8.1   235   22   12   6.5   3.5   47.6 117.8    11.4      M    M
 27000  -20.4  -4.7   240   24   12   6.6   3.6   46.3 115.4    10.5      M    M
 26000  -18.4  -1.1   240   26   13   6.6   3.6   45.2 113.3     9.6      M    M
 25000  -16.5   2.3   240   27   14   7.1   3.9   44.1 111.4     8.9      M    M
 24000  -14.2   6.4   240   28   14   7.5   4.1   43.2 109.7     8.2      M    M
 23000  -12.0  10.4   240   29   15   7.5   4.1   42.4 108.3     7.6      M    M
 22000   -9.7  14.5   235   30   16   7.6   4.1   41.7 107.0     7.1      M    M
 21000   -7.5  18.5   240   29   15   7.6   4.2   40.8 105.5     6.4      M    M
 20000   -5.3  22.5   240   28   14   7.6   4.2   40.1 104.1     5.8      M    M
 19500   -4.1  24.6   240   27   14   7.6   4.2   39.8 103.6     5.5      M    M
 19000   -3.1  26.4   240   26   13   7.0   3.8   39.3 102.8     5.2      M    M
 18500   -2.1  28.2   240   25   13   7.1   3.9   38.9 102.0     4.7      M    M
 18000   -1.1  30.0   245   24   12   7.0   3.8   38.4 101.2     4.3      M    M
 17500    0.5  32.9   245   21   11   6.9   3.8   37.7  99.8     3.7      M    M
 17000    1.5  34.7   245   20   10   6.3   3.4   37.2  99.0     3.3      M    M
 16500    2.3  36.1   250   18    9   5.8   3.2   36.5  97.7     2.6      M    M
 16000    3.1  37.6   250   15    8   5.8   3.2   35.9  96.5     2.0      M    M
 15500    3.9  39.0   250   14    7   5.8   3.2   35.2  95.3     1.4      M    M
 15000    4.7  40.5   255   12    6   5.7   3.1   34.5  94.1     0.7      M    M
 14500    5.6  42.1   255   10    5   7.0   3.8   33.9  93.1     0.1      M    M
 14000    6.6  43.9   260    9    5   7.1   3.9   33.5  92.3    -0.3    712  3.6
 13500    7.6  45.7   265    8    4   7.5   4.1   33.1  91.5    -0.8    666  3.4
 13000    8.8  47.8   270    7    4   7.7   4.2   32.7  90.9    -1.1    618  3.1
 12500    9.9  49.8   275    7    4   7.7   4.2   32.4  90.4    -1.4    569  2.9
 12000   11.0  51.8   280    7    3   7.5   4.1   32.1  89.7    -1.8    521  2.6
 11500   12.1  53.8   285    7    3   7.1   3.9   31.7  89.1    -2.2    473  2.4
 11000   13.1  55.6   290    7    3   6.1   3.3   31.2  88.2    -2.7    430  2.2
 10500   14.0  57.2   295    7    4   3.0   1.6   30.7  87.2    -3.2    387  2.0
 10250   14.1  57.4   295    7    4   4.4   2.4   30.0  86.0    -3.8    376  1.9
 10000   14.7  58.5   300    7    3   9.6   5.3   29.9  85.9    -4.0    350  1.8
  9750   15.4  59.7   300    6    3   8.4   4.6   29.8  85.7    -4.1    324  1.6
  9500   16.0  60.8   300    6    3   8.1   4.5   29.7  85.5    -4.2    298  1.5
  9250   16.5  61.7   305    6    3   7.4   4.1   29.6  85.2    -4.4    274  1.4
  9000   17.1  62.8   305    6    3   8.4   4.6   29.4  85.0    -4.5    249  1.3
  8750   17.8  64.0   305    6    3   9.2   5.1   29.4  84.9    -4.6    221  1.1
  8500   18.5  65.3   310    6    3   8.3   4.6   29.3  84.7    -4.7    194  1.0
  8250   19.0  66.2   315    6    3   7.4   4.0   29.1  84.5    -4.8    169  0.9
  8000   19.6  67.3   315    7    3   7.4   4.1   29.0  84.1    -5.0    145  0.7
  7750   20.1  68.2   320    7    4   7.7   4.2   28.8  83.8    -5.2    121  0.6
  7500   20.7  69.3   320    8    4   6.9   3.8   28.6  83.5    -5.4     97  0.5
  7250   21.2  70.2   320    9    4   6.2   3.4   28.4  83.0    -5.7     76  0.4
  7000   21.6  70.9   320   10    5   6.6   3.6   28.1  82.6    -5.9     55  0.3
  6750   22.1  71.8   320   11    6   4.7   2.6   27.8  82.1    -6.2     34  0.2
  6500   22.2  72.0   315   11    6  -0.9  -0.5   27.2  81.0    -6.9     23  0.1
  6250   21.9  71.4   310   10    5  -3.8  -2.1   26.3  79.3    -7.9     25  0.1
  6000   21.6  70.9   300    9    5  -2.1  -1.1   25.3  77.6    -9.0     27  0.1
  5750   21.3  70.3   290    8    4  -4.3  -2.4   24.4  75.9   -10.0     27  0.1
  5500   20.6  69.1   265    5    3 -10.8  -5.9   23.1  73.6   -11.4     40  0.2

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

           07/21/2017 at 0900 MDT          |       07/21/2017 at 1200 MDT
                                           |
K index... +28.1  LI... +1.4               | K index... +30.4  LI... -0.7
CAPE... +0.3  CIN... -46.4                 | CAPE... +164.8  CIN... -53.0
                                           |
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 -66.0 -86.8  250  17  9   2.3   1.3 | -65.7 -86.3  235  22 11   3.1   1.7
 45000 -60.4 -76.7  250  20 10   5.9   3.2 | -59.9 -75.8  230  23 12   5.4   2.9
 40000 -51.0 -59.8  250  22 11   8.2   4.5 | -50.6 -59.1  230  19 10   8.0   4.4
 38000 -46.1 -51.0  230  18  9   8.1   4.5 | -45.8 -50.4  220  18  9   8.1   4.4
 36000 -41.2 -42.2  210  16  8   8.0   4.4 | -41.0 -41.8  205  17  9   7.9   4.3
 34000 -36.0 -32.8  220  12  6   7.8   4.3 | -36.3 -33.3  210  14  7   7.8   4.3
 32000 -31.3 -24.3  235   9  5   8.0   4.4 | -31.6 -24.9  215  12  6   7.9   4.3
 30000 -27.0 -16.6  240  11  6   7.1   3.9 | -27.3 -17.1  225  12  6   7.2   3.9
 29000 -24.9 -12.8  240  12  6   7.2   3.9 | -25.2 -13.4  230  12  6   7.2   4.0
 28000 -22.8  -9.0  245  13  7   6.7   3.6 | -22.6  -8.7  235  12  6   7.0   3.8
 27000 -20.9  -5.6  245  15  8   6.7   3.7 | -20.5  -4.9  235  13  7   7.0   3.9
 26000 -18.9  -2.0  250  17  9   6.7   3.7 | -18.4  -1.1  235  14  7   7.1   3.9
 25000 -16.9   1.6  250  19 10   7.2   4.0 | -16.4   2.5  240  15  8   7.3   4.0
 24000 -14.6   5.7  255  19 10   7.6   4.2 | -14.2   6.4  240  15  8   7.4   4.0
 23000 -12.4   9.7  260  19 10   7.7   4.2 | -12.1  10.2  245  14  7   7.4   4.1
 22000 -10.2  13.6  260  20 10   7.6   4.2 | -10.0  14.0  250  14  7   7.2   4.0
 21000  -7.9  17.8  265  18  9   7.6   4.2 |  -7.9  17.8  255  12  6   7.2   4.0
 20000  -5.7  21.7  275  17  9   7.6   4.2 |  -5.7  21.7  260  10  5   7.2   4.0
 19500  -4.5  23.9  275  16  8   7.6   4.1 |  -4.7  23.5  265   9  5   6.9   3.8
 19000  -3.6  25.5  285  16  8   5.8   3.2 |  -3.8  25.2  275   8  4   5.9   3.3
 18500  -2.7  27.1  290  15  8   6.0   3.3 |  -2.9  26.8  290   8  4   6.0   3.3
 18000  -1.5  29.3  300  14  7   5.3   2.9 |  -2.1  28.2  300   8  4   6.1   3.3
 17500  -0.8  30.6  305  14  7   5.4   3.0 |  -1.2  29.8  310   8  4   6.1   3.4
 17000  -0.0  32.0  310  13  7   5.9   3.3 |  -0.4  31.3  320   9  4   6.3   3.4
 16500   0.9  33.6  320  13  6   6.3   3.4 |   0.6  33.1  325   9  5   7.0   3.9
 16000   1.7  35.1  325  12  6   6.4   3.5 |   1.6  34.9  330   9  5   7.0   3.9
 15500   2.8  37.0  330  11  6   7.5   4.1 |   2.6  36.7  330  10  5   7.0   3.8
 15000   3.9  39.0  340  11  5   7.4   4.0 |   4.1  39.4  335  10  5   6.9   3.8
 14500   5.0  41.0  340  10  5   7.6   4.2 |   5.1  41.2  340  10  5   8.2   4.5
 14000   6.1  43.0  345  10  5   7.6   4.2 |   6.3  43.3  340  10  5   8.1   4.5
 13500   7.2  45.0  345  10  5   8.0   4.4 |   7.5  45.5  345  10  5   7.9   4.4
 13000   8.4  47.1  345  10  5   8.1   4.5 |   8.6  47.5  345  10  5   7.9   4.3
 12500   9.6  49.3  350  10  5   7.9   4.3 |   9.8  49.6  345  10  5   7.9   4.3
 12000  10.8  51.4  350  10  5   7.7   4.2 |  10.9  51.6  350  10  5   7.9   4.3
 11500  11.9  53.4  350  10  5   7.9   4.3 |  12.0  53.6  350  10  5   8.0   4.4
 11000  13.2  55.8  350   9  5   7.9   4.3 |  13.3  55.9  355   9  5   8.0   4.4
 10500  14.4  57.9  345   9  5   3.0   1.6 |  14.5  58.1  355   9  4   4.7   2.6
 10250  14.4  57.9  345   9  4   3.6   2.0 |  14.7  58.5  360   8  4   5.5   3.0
 10000  15.1  59.2  345   8  4  10.7   5.8 |  15.4  59.7  360   7  3  10.3   5.7
  9750  15.7  60.3  345   8  4   9.2   5.1 |  16.1  61.0  005   5  3   9.4   5.2
  9500  16.4  61.5  345   7  4   7.9   4.3 |  16.8  62.2  015   4  2   8.2   4.5
  9250  16.9  62.4  345   7  4   5.7   3.1 |  17.3  63.1  015   4  2   7.6   4.2
  9000  17.4  63.3  350   6  3   7.1   3.9 |  18.0  64.4  015   3  2   9.8   5.4
  8750  17.9  64.2  355   6  3   7.9   4.3 |  18.7  65.7  015   3  2  10.1   5.6
  8500  18.5  65.3  360   5  3   6.9   3.8 |  19.4  66.9  020   3  2  10.1   5.5
  8250  18.9  66.0  005   4  2   5.9   3.2 |  20.2  68.4  020   3  2  10.2   5.6
  8000  19.3  66.7  015   3  2   6.5   3.6 |  20.9  69.6  020   3  1   9.8   5.4
  7750  19.8  67.6  020   3  1   6.9   3.8 |  21.7  71.1  020   3  1   9.6   5.3
  7500  20.4  68.7  025   2  1   8.3   4.5 |  22.4  72.3  020   3  1  10.3   5.7
  7250  21.0  69.8  360   2  1   9.3   5.1 |  23.2  73.8  020   3  1  10.8   5.9
  7000  21.7  71.1  340   2  1   9.1   5.0 |  24.0  75.2  015   3  1  10.4   5.7
  6750  22.4  72.3  325   3  2   8.2   4.5 |  24.7  76.5  015   2  1  10.3   5.7
  6500  22.9  73.2  320   4  2   6.3   3.5 |  25.5  77.9  015   2  1  10.6   5.8
  6250  23.3  73.9  310   4  2   6.6   3.6 |  26.3  79.3  015   2  1  11.6   6.4
  6000  23.7  74.7  300   4  2   3.9   2.1 |  27.2  81.0  015   2  1   8.6   4.7
  5750  24.0  75.2  280   3  2   8.1   4.5 |  27.8  82.0  015   2  1  14.7   8.1
  5500  25.2  77.4  275   3  2  24.2  13.3 |  29.6  85.3  015   2  1  33.4  18.3

           07/21/2017 at 1500 MDT          |       07/21/2017 at 1800 MDT
                                           |
K index... +31.2  LI... -2.5               | K index... +34.1  LI... -2.1
CAPE... +545.7  CIN... -10.7               | CAPE... +476.9  CIN... -130.6
                                           |
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 -66.0 -86.8  245  26 13   2.9   1.6 | -65.7 -86.3  250  25 13   2.3   1.2
 45000 -60.0 -76.0  250  24 13   5.9   3.2 | -60.5 -76.9  260  27 14   5.5   3.0
 40000 -50.3 -58.5  265  17  9   7.3   4.0 | -50.8 -59.4  285  26 13   8.9   4.9
 38000 -45.9 -50.6  255  16  8   7.3   4.0 | -45.4 -49.7  290  24 12   8.9   4.9
 36000 -41.4 -42.5  245  16  8   8.2   4.5 | -40.1 -40.2  295  22 12   8.3   4.5
 34000 -36.4 -33.5  250  16  8   8.4   4.6 | -35.2 -31.4  295  18  9   8.2   4.5
 32000 -31.4 -24.5  255  15  8   8.4   4.6 | -30.3 -22.5  300  14  7   9.0   4.9
 30000 -26.9 -16.4  260  15  8   7.5   4.1 | -25.8 -14.4  290   9  5   7.6   4.2
 29000 -24.6 -12.3  260  15  8   7.5   4.1 | -23.6 -10.5  280   7  4   7.6   4.2
 28000 -21.9  -7.4  260  15  8   7.1   3.9 | -21.0  -5.8  255   7  3   5.5   3.0
 27000 -19.8  -3.6  255  15  8   7.1   3.9 | -19.4  -2.9  230  10  5   5.6   3.0
 26000 -17.7   0.1  250  14  7   7.2   3.9 | -17.7   0.1  220  14  7   5.6   3.0
 25000 -15.6   3.9  250  14  7   7.1   3.9 | -16.0   3.2  215  17  9   7.1   3.9
 24000 -13.5   7.7  245  13  7   7.1   3.9 | -13.8   7.2  220  19 10   7.6   4.2
 23000 -11.5  11.3  240  13  7   7.1   3.9 | -11.5  11.3  225  20 11   7.6   4.2
 22000  -9.4  15.1  240  12  6   6.2   3.4 |  -9.3  15.3  225  22 11   6.7   3.7
 21000  -7.7  18.1  235  11  6   6.1   3.3 |  -7.5  18.5  220  19 10   6.5   3.6
 20000  -6.0  21.2  235   9  5   6.2   3.4 |  -5.7  21.7  215  17  9   6.6   3.6
 19500  -5.2  22.6  230   9  4   6.3   3.5 |  -4.7  23.5  210  16  8   6.5   3.6
 19000  -4.2  24.4  230   7  4   6.6   3.6 |  -3.9  25.0  205  14  7   5.8   3.2
 18500  -3.2  26.2  230   6  3   6.6   3.6 |  -3.1  26.4  200  13  7   5.8   3.2
 18000  -2.3  27.9  235   5  2   6.8   3.7 |  -2.3  27.9  190  12  6   5.9   3.3
 17500  -1.3  29.7  245   4  2   6.9   3.8 |  -1.4  29.5  185  11  5   6.0   3.3
 17000  -0.3  31.5  260   4  2   7.1   3.9 |  -0.6  30.9  175  10  5   6.0   3.3
 16500   0.7  33.3  270   3  1   7.5   4.1 |   0.2  32.4  165   9  5   5.8   3.2
 16000   1.8  35.2  285   2  1   7.5   4.1 |   1.0  33.8  160   8  4   5.8   3.2
 15500   2.8  37.0  315   1  1   7.2   4.0 |   1.8  35.2  150   7  4   5.8   3.2
 15000   4.4  39.9  030   2  1   7.2   3.9 |   3.0  37.4  140   5  2   5.5   3.0
 14500   5.5  41.9  040   3  1   8.1   4.5 |   4.0  39.2  120   3  2   8.7   4.8
 14000   6.6  43.9  045   3  2   8.1   4.4 |   5.2  41.4  100   2  1   8.4   4.6
 13500   7.8  46.0  045   4  2   8.3   4.5 |   6.5  43.7  065   2  1   9.6   5.3
 13000   9.0  48.2  045   4  2   8.3   4.6 |   7.9  46.2  055   2  1   9.9   5.4
 12500  10.2  50.4  045   4  2   8.9   4.9 |   9.4  48.9  050   2  1   9.7   5.3
 12000  11.5  52.7  040   4  2   9.2   5.0 |  10.8  51.4  020   2  1   9.6   5.2
 11500  12.8  55.0  040   4  2   9.4   5.2 |  12.3  54.1  005   3  2   8.7   4.8
 11000  14.3  57.7  035   3  2   9.4   5.2 |  13.4  56.1  350   8  4   7.4   4.1
 10500  15.7  60.3  035   3  2   4.7   2.6 |  14.4  57.9  345  14  7   3.7   2.0
 10250  15.9  60.6  030   3  2   5.9   3.3 |  14.5  58.1  345  15  8   2.2   1.2
 10000  16.7  62.1  030   3  2  13.0   7.2 |  14.9  58.8  345  18  9   6.1   3.3
  9750  17.6  63.7  030   3  2  11.7   6.4 |  15.3  59.5  345  20 11   5.5   3.0
  9500  18.5  65.3  025   3  2   9.9   5.4 |  15.7  60.3  345  23 12   4.1   2.2
  9250  19.1  66.4  025   3  2   8.7   4.8 |  15.9  60.6  345  26 13   2.1   1.2
  9000  19.8  67.6  025   3  2  10.8   5.9 |  16.1  61.0  345  28 14   3.1   1.7
  8750  20.6  69.1  020   3  2  11.0   6.0 |  16.3  61.3  345  30 15   3.7   2.0
  8500  21.5  70.7  020   3  2  10.4   5.7 |  16.6  61.9  350  32 17   3.2   1.7
  8250  22.2  72.0  020   3  2   9.8   5.4 |  16.8  62.2  350  34 18   2.6   1.4
  8000  22.9  73.2  015   3  2   9.9   5.4 |  17.0  62.6  350  36 19   3.3   1.8
  7750  23.7  74.7  015   3  2   9.7   5.3 |  17.2  63.0  350  38 20   4.1   2.2
  7500  24.4  75.9  010   3  2  10.1   5.6 |  17.5  63.5  350  39 20   5.4   2.9
  7250  25.2  77.4  010   3  2  10.4   5.7 |  17.9  64.2  350  39 20   6.4   3.5
  7000  25.9  78.6  010   3  2  10.5   5.8 |  18.2  64.8  350  38 20   5.8   3.2
  6750  26.7  80.1  005   3  2  10.9   6.0 |  18.6  65.5  350  37 19   7.5   4.1
  6500  27.5  81.5  005   3  2  10.5   5.8 |  19.2  66.6  350  35 18  10.4   5.7
  6250  28.3  82.9  005   3  2  10.7   5.9 |  20.0  68.0  350  33 17  11.7   6.4
  6000  29.1  84.4  360   3  2   9.5   5.2 |  20.9  69.6  350  31 16   9.3   5.1
  5750  29.9  85.8  360   3  2  15.9   8.7 |  21.6  70.9  350  30 16  13.1   7.2
  5500  31.6  88.9  360   3  2  31.2  17.1 |  23.0  73.4  355  25 13  25.8  14.1
________________________________________________________________________________

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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