Soaring Guidance
Issued by NWS Denver/Boulder, CO

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UXUS97 KBOU 200130
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1930 MDT Thursday, May 19, 2016

This forecast is for Friday, May 20, 2016:

If the trigger temperature of 70.8 F/21.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1192 ft/min (6.1 m/s)
   Maximum height of thermals.................. 18276 ft MSL (12969 ft AGL)

Forecast maximum temperature................... 81.0 F/27.7 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 14531 ft MSL (9225 ft AGL)
Thermal soaring outlook for Saturday 05/21..... Excellent

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....................... 21339 ft MSL (16032 ft AGL)
Wave soaring outlook for Saturday 05/21........ Poor

Remarks...

Sunrise/Sunset.................... 05:40:21 / 20:11:35 MDT
Total possible sunshine........... 14 hr 31 min 14 sec (871 min 14 sec)
Altitude of sun at 12:56:10 MDT... 70.40 degrees

Upper air data from numerical model forecast valid on 05/20/2016 at 0600 MDT

Freezing level.................. 12916 ft MSL (7609 ft AGL)
Convective condensation level... 14347 ft MSL (9040 ft AGL)
Lifted condensation level....... 15798 ft MSL (10492 ft AGL)
Lifted index.................... -3.3
K index......................... +20.1

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  -61.1 -78.0   270   22   12  -1.9  -1.1      M     M       M      M    M
 45000  -64.0 -83.2   270   32   17  -0.6  -0.3      M     M       M      M    M
 40000  -64.2 -83.6   275   34   17  -0.2  -0.1      M     M       M      M    M
 38000  -61.0 -77.8   275   31   16   8.4   4.6      M     M       M      M    M
 36000  -55.3 -67.5   270   27   14   8.4   4.6      M     M       M      M    M
 34000  -50.2 -58.4   270   24   12   8.7   4.8      M     M       M      M    M
 32000  -44.9 -48.8   265   20   11   8.7   4.8      M     M       M      M    M
 30000  -39.6 -39.3   270   19   10   9.0   5.5   35.6  96.2     6.4      M    M
 29000  -36.9 -34.4   270   19   10   9.0   5.0   35.3  95.6     6.2      M    M
 28000  -34.2 -29.6   270   19   10   9.0   5.0   35.1  95.2     6.1      M    M
 27000  -31.6 -24.9   270   19   10   8.1   4.4   34.8  94.6     5.9      M    M
 26000  -29.1 -20.4   265   17    9   8.1   4.5   34.1  93.3     5.4      M    M
 25000  -26.7 -16.1   260   16    8   8.2   4.5   33.5  92.3     5.0      M    M
 24000  -24.3 -11.7   260   15    8   7.4   4.1   32.9  91.3     4.5      M    M
 23000  -22.1  -7.8   260   15    8   7.4   4.0   32.0  89.6     3.8      M    M
 22000  -19.9  -3.8   260   15    8   7.4   4.1   31.1  88.0     3.1      M    M
 21000  -17.8  -0.0   265   15    8   7.2   3.9   30.3  86.6     2.4      M    M
 20000  -15.6   3.9   270   13    7   7.2   4.0   29.4  84.8     1.6      M    M
 19500  -14.6   5.7   270   13    7   7.2   4.0   28.9  84.1     1.2      M    M
 19000  -13.5   7.7   270   12    6   7.3   4.0   28.5  83.3     0.8      M    M
 18500  -12.0  10.4   280   11    6   6.2   3.4   27.7  81.9     0.1      M    M
 18000  -11.1  12.0   285   10    5   6.1   3.4   27.1  80.9    -0.4   1159  5.9
 17500  -10.2  13.6   290   10    5   7.2   3.9   26.6  79.9    -0.9   1115  5.7
 17000   -9.1  15.6   295   10    5   7.4   4.0   26.2  79.1    -1.3   1068  5.4
 16500   -8.0  17.6   300    9    5   7.5   4.1   25.8  78.4    -1.7   1021  5.2
 16000   -6.8  19.8   300    9    5   7.8   4.3   25.4  77.8    -2.0    970  4.9
 15500   -5.6  21.9   300    9    4   7.8   4.3   25.1  77.2    -2.3    920  4.7
 15000   -4.5  23.9   300    8    4   6.9   3.8   24.7  76.5    -2.7    872  4.4
 14500   -3.5  25.7   295    8    4   7.0   3.8   24.3  75.7    -3.1    825  4.2
 14000   -2.4  27.7   295    7    4   7.6   4.2   23.8  74.9    -3.5    778  4.0
 13500   -1.3  29.7   295    6    3   7.7   4.2   23.5  74.3    -3.8    729  3.7
 13000   -0.1  31.8   295    6    3   8.6   4.7   23.2  73.8    -4.2    680  3.5
 12500    1.2  34.2   300    5    3   8.9   4.9   23.1  73.5    -4.4    627  3.2
 12000    2.4  36.3   315    5    3   8.9   4.9   22.9  73.3    -4.6    574  2.9
 11500    3.7  38.7   320    6    3   8.9   4.9   22.8  73.0    -4.8    520  2.6
 11000    5.0  41.0   330    7    3   8.5   4.7   22.7  72.8    -5.0    467  2.4
 10500    6.2  43.2   330    8    4   7.8   4.3   22.4  72.4    -5.3    415  2.1
 10250    6.9  44.4   330    9    4  10.6   5.8   22.3  72.2    -5.4    390  2.0
 10000    7.8  46.0   330   10    5  11.1   6.1   22.5  72.5    -5.2    355  1.8
  9750    8.4  47.1   325   11    6   8.5   4.7   22.4  72.4    -5.3    328  1.7
  9500    9.1  48.4   325   12    6   9.4   5.1   22.4  72.3    -5.4    301  1.5
  9250    9.8  49.6   325   13    7   8.5   4.7   22.3  72.2    -5.5    273  1.4
  9000   10.3  50.5   320   15    7   8.0   4.4   22.2  72.0    -5.6    249  1.3
  8750   10.9  51.6   315   15    8   8.3   4.6   22.1  71.8    -5.8    223  1.1
  8500   11.5  52.7   310   16    8   8.2   4.5   22.0  71.6    -5.9    198  1.0
  8250   12.1  53.8   310   17    9   8.5   4.7   21.9  71.4    -6.1    172  0.9
  8000   12.8  55.0   305   18    9   7.8   4.3   21.8  71.2    -6.2    146  0.7
  7750   13.3  55.9   305   17    9   6.2   3.4   21.6  70.8    -6.4    123  0.6
  7500   13.7  56.7   305   16    8   6.1   3.4   21.3  70.3    -6.7    103  0.5
  7250   14.2  57.6   305   15    8   5.3   2.9   21.0  69.8    -7.0     82  0.4
  7000   14.5  58.1   305   14    7   4.0   2.2   20.6  69.0    -7.5     65  0.3
  6750   14.7  58.5   305   13    7   2.9   1.6   20.1  68.2    -8.0     50  0.3
  6500   14.9  58.8   310   11    6   1.0   0.5   19.5  67.1    -8.6     39  0.2
  6250   14.7  58.5   310   10    5  -8.1  -4.5   18.6  65.5    -9.5     37  0.2
  6000   13.7  56.7   300    7    4 -13.7  -7.5   16.9  62.4   -11.3     59  0.3
  5750   12.7  54.9   275    6    3 -15.7  -8.6   15.1  59.2   -13.1     83  0.4
  5500   10.8  51.4   235    8    4 -35.0 -19.2   12.6  54.7   -15.7    131  0.7

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

           05/20/2016 at 0900 MDT          |       05/20/2016 at 1200 MDT
                                           |
K index... +18.9  LI... 0.0                | K index... +21.0  LI... -0.9
CAPE... 0.0  CIN... -0.7                   | CAPE... +177.1  CIN... -34.9
                                           |
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  21 11  -2.0  -1.1 | -61.0 -77.8  270  22 11  -1.0  -0.5
 45000 -63.9 -83.0  275  36 18  -0.7  -0.4 | -62.5 -80.5  275  35 18  -0.4  -0.2
 40000 -63.8 -82.8  265  39 20   0.3   0.1 | -63.2 -81.8  260  39 20  -0.3  -0.1
 38000 -60.4 -76.7  260  36 18   7.7   4.2 | -60.1 -76.2  260  34 18   7.1   3.9
 36000 -55.8 -68.4  260  31 16   7.7   4.2 | -55.9 -68.6  260  27 14   7.1   3.9
 34000 -51.0 -59.8  255  26 14   8.9   4.9 | -51.1 -60.0  255  24 12   9.3   5.1
 32000 -45.6 -50.1  255  24 12   8.9   4.9 | -44.8 -48.6  260  25 13   9.3   5.1
 30000 -39.6 -39.3  255  22 11   9.1   5.0 | -39.4 -38.9  260  25 13   9.0   4.9
 29000 -36.9 -34.4  255  22 11   9.1   5.0 | -36.7 -34.1  260  25 13   9.0   4.9
 28000 -34.1 -29.4  255  21 11   9.1   5.0 | -34.0 -29.2  260  24 13   9.0   4.9
 27000 -31.5 -24.7  255  22 11   8.6   4.7 | -31.4 -24.5  260  24 12   8.4   4.6
 26000 -28.9 -20.0  250  22 12   8.6   4.7 | -28.9 -20.0  260  24 13   8.4   4.6
 25000 -26.4 -15.5  250  23 12   8.6   4.7 | -26.4 -15.5  260  24 13   8.4   4.6
 24000 -23.9 -11.0  250  24 12   7.9   4.4 | -24.0 -11.2  260  24 12   7.8   4.3
 23000 -21.5  -6.7  255  23 12   8.0   4.4 | -21.6  -6.9  260  24 12   7.8   4.3
 22000 -19.1  -2.4  260  23 12   8.0   4.4 | -19.3  -2.7  260  23 12   7.8   4.3
 21000 -17.0   1.4  265  21 11   5.8   3.2 | -17.1   1.2  255  23 12   6.9   3.8
 20000 -15.2   4.6  260  18  9   6.0   3.3 | -15.1   4.8  255  22 11   7.0   3.8
 19500 -14.3   6.3  260  16  8   5.9   3.3 | -14.0   6.8  255  21 11   7.0   3.8
 19000 -13.4   7.9  260  15  8   5.8   3.2 | -13.0   8.6  250  21 11   7.1   3.9
 18500 -12.5   9.5  255  13  7   7.2   3.9 | -12.1  10.2  250  20 10   6.2   3.4
 18000 -11.4  11.5  255  12  6   7.1   3.9 | -11.1  12.0  245  19 10   6.3   3.5
 17500 -10.4  13.3  255  10  5   7.1   3.9 | -10.2  13.6  245  18  9   6.9   3.8
 17000  -9.3  15.3  255   9  4   7.2   3.9 |  -9.1  15.6  245  16  8   7.4   4.1
 16500  -8.2  17.2  255   7  4   7.2   3.9 |  -7.4  18.7  240  14  7   7.5   4.1
 16000  -7.2  19.0  255   6  3   7.2   4.0 |  -6.3  20.7  240  13  7   7.6   4.2
 15500  -5.6  21.9  250   4  2   7.3   4.0 |  -5.2  22.6  240  12  6   7.6   4.2
 15000  -4.5  23.9  250   3  2   7.3   4.0 |  -4.1  24.6  235  11  6   7.6   4.2
 14500  -3.5  25.7  245   3  1   7.3   4.0 |  -3.0  26.6  230  10  5   7.6   4.2
 14000  -2.4  27.7  235   2  1   7.8   4.3 |  -1.9  28.6  225   9  5   7.2   3.9
 13500  -1.2  29.8  210   2  1   7.7   4.2 |  -0.8  30.6  220   8  4   7.2   3.9
 13000  -0.1  31.8  170   1  1   8.3   4.6 |   0.3  32.5  210   7  4   7.4   4.1
 12500   1.1  34.0  130   2  1   8.4   4.6 |   1.4  34.5  205   7  4   7.3   4.0
 12000   2.3  36.1  105   2  1   8.3   4.6 |   2.5  36.5  195   7  3   8.8   4.8
 11500   3.5  38.3  095   3  2   8.3   4.6 |   3.8  38.8  190   6  3   9.1   5.0
 11000   4.7  40.5  085   4  2   7.4   4.1 |   5.1  41.2  180   6  3   7.6   4.2
 10500   5.7  42.3  075   4  2   6.5   3.6 |   6.1  43.0  170   6  3   6.6   3.6
 10250   6.2  43.2  070   5  2   9.7   5.3 |   6.7  44.1  170   7  3  10.3   5.6
 10000   7.1  44.8  065   5  3  10.7   5.9 |   7.6  45.7  160   6  3  10.9   6.0
  9750   7.7  45.9  060   5  3   8.3   4.6 |   8.2  46.8  160   6  3   7.5   4.1
  9500   8.4  47.1  050   5  3   8.8   4.9 |   8.7  47.7  155   5  3   8.6   4.7
  9250   9.0  48.2  040   5  3   9.1   5.0 |   9.3  48.7  150   5  2   7.9   4.3
  9000   9.7  49.5  030   5  3   9.8   5.4 |   9.9  49.8  155   4  2   8.6   4.7
  8750  10.4  50.7  020   5  3   9.8   5.4 |  10.6  51.1  155   4  2   9.7   5.3
  8500  11.2  52.2  010   5  3   9.8   5.4 |  11.2  52.2  155   3  2   9.1   5.0
  8250  11.9  53.4  360   5  3  10.0   5.5 |  11.9  53.4  160   3  2  10.6   5.8
  8000  12.6  54.7  340   6  3   8.7   4.8 |  12.8  55.0  165   3  1  11.1   6.1
  7750  13.1  55.6  320   6  3   6.5   3.6 |  13.5  56.3  165   3  1   9.6   5.3
  7500  13.6  56.5  310   7  4   6.4   3.5 |  14.2  57.6  165   3  1   9.6   5.3
  7250  14.0  57.2  300   8  4   5.0   2.7 |  15.0  59.0  165   3  1  10.1   5.5
  7000  14.3  57.7  295   7  4   3.4   1.9 |  15.7  60.3  165   2  1  10.3   5.6
  6750  14.5  58.1  290   6  3   2.3   1.3 |  16.5  61.7  170   2  1   9.3   5.1
  6500  14.6  58.3  275   5  3   1.7   0.9 |  17.1  62.8  170   2  1   9.7   5.3
  6250  14.8  58.6  260   4  2   2.6   1.4 |  17.9  64.2  170   2  1  11.3   6.2
  6000  15.0  59.0  240   4  2   2.8   1.5 |  18.8  65.8  175   2  1  11.6   6.4
  5750  15.2  59.4  220   4  2   3.5   1.9 |  19.6  67.3  175   2  1  10.6   5.8
  5500  15.5  59.9  210   4  2  10.2   5.6 |  20.5  68.9  175   2  1  14.4   7.9

           05/20/2016 at 1500 MDT          |       05/20/2016 at 1800 MDT
                                           |
K index... +25.6  LI... -1.5               | K index... +28.7  LI... -2.0
CAPE... +552.0  CIN... -21.1               | CAPE... +706.6  CIN... -1.9
                                           |
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 -60.8 -77.4  265  25 13  -0.5  -0.3 | -61.7 -79.1  265  25 13  -0.5  -0.3
 45000 -61.7 -79.1  265  38 20  -0.9  -0.5 | -62.5 -80.5  255  33 17  -0.5  -0.3
 40000 -63.0 -81.4  265  42 22  -0.6  -0.3 | -63.2 -81.8  255  31 16  -0.2  -0.1
 38000 -59.9 -75.8  260  39 20   7.1   3.9 | -59.7 -75.5  255  30 15   7.8   4.3
 36000 -55.6 -68.1  260  33 17   7.1   3.9 | -54.4 -65.9  260  29 15   7.8   4.3
 34000 -50.1 -58.2  260  30 15   9.3   5.1 | -49.3 -56.7  260  30 15   9.3   5.1
 32000 -44.5 -48.1  260  29 15   9.3   5.1 | -43.7 -46.7  260  31 16   9.3   5.1
 30000 -39.0 -38.2  260  29 15   9.0   4.9 | -38.3 -36.9  260  32 16   8.7   4.8
 29000 -36.4 -33.5  260  29 15   9.0   4.9 | -35.7 -32.3  265  32 16   8.7   4.8
 28000 -33.7 -28.7  260  29 15   9.0   4.9 | -33.1 -27.6  265  32 17   8.7   4.8
 27000 -31.1 -24.0  260  28 14   8.0   4.4 | -30.6 -23.1  265  32 17   8.0   4.4
 26000 -28.8 -19.8  265  27 14   8.0   4.4 | -28.2 -18.8  265  32 16   8.0   4.4
 25000 -26.4 -15.5  265  27 14   8.0   4.4 | -25.8 -14.4  265  31 16   8.0   4.4
 24000 -24.0 -11.2  265  26 13   8.2   4.5 | -23.5 -10.3  265  30 16   8.0   4.4
 23000 -21.6  -6.9  265  25 13   8.2   4.5 | -21.1  -6.0  265  29 15   8.0   4.4
 22000 -19.1  -2.4  265  23 12   8.2   4.5 | -18.7  -1.7  260  27 14   8.0   4.4
 21000 -16.8   1.8  260  22 11   7.7   4.2 | -16.3   2.7  260  26 13   7.7   4.2
 20000 -14.5   5.9  260  21 11   7.7   4.2 | -14.1   6.6  255  26 14   7.7   4.2
 19500 -13.4   7.9  255  20 10   7.7   4.2 | -12.9   8.8  255  27 14   7.7   4.2
 19000 -12.2  10.0  255  20 10   7.7   4.2 | -11.8  10.8  255  27 14   7.7   4.2
 18500 -11.1  12.0  255  20 10   7.5   4.1 | -10.2  13.6  250  26 13   7.1   3.9
 18000 -10.0  14.0  255  21 11   7.5   4.1 |  -9.2  15.4  245  25 13   7.1   3.9
 17500  -8.9  16.0  255  21 11   7.0   3.8 |  -8.2  17.2  240  25 13   7.1   3.9
 17000  -7.4  18.7  245  21 11   6.6   3.6 |  -7.1  19.2  235  25 13   7.1   3.9
 16500  -6.5  20.3  240  21 11   7.2   3.9 |  -6.1  21.0  230  25 13   7.5   4.1
 16000  -5.4  22.3  235  21 11   7.4   4.1 |  -5.0  23.0  220  24 12   7.6   4.2
 15500  -4.3  24.3  230  22 11   7.7   4.2 |  -3.9  25.0  215  23 12   7.4   4.1
 15000  -3.1  26.4  230  21 11   8.4   4.6 |  -2.9  26.8  205  21 11   6.6   3.6
 14500  -1.9  28.6  225  20 10   8.5   4.6 |  -1.9  28.6  195  19 10   6.7   3.7
 14000  -0.7  30.7  220  19 10   8.0   4.4 |  -0.9  30.4  185  17  9   7.3   4.0
 13500   0.5  32.9  215  17  9   8.1   4.5 |   0.1  32.2  175  16  8   7.0   3.8
 13000   1.6  34.9  205  15  8   7.8   4.3 |   1.3  34.3  165  14  7   9.6   5.3
 12500   2.7  36.9  190  13  7   7.9   4.3 |   2.7  36.9  160  13  7   9.6   5.3
 12000   3.9  39.0  175  12  6   8.0   4.4 |   4.1  39.4  155  13  7   9.9   5.4
 11500   5.0  41.0  170  11  6   8.1   4.4 |   5.6  42.1  150  12  6  10.0   5.5
 11000   6.2  43.2  160  10  5   7.6   4.1 |   7.0  44.6  150  12  6   8.9   4.9
 10500   7.3  45.1  155   9  5   6.7   3.7 |   8.3  46.9  150  12  6   8.3   4.5
 10250   7.8  46.0  150   9  5  10.8   5.9 |   9.0  48.2  150  12  6  12.1   6.7
 10000   8.8  47.8  150   8  4  12.2   6.7 |  10.0  50.0  150  11  6  12.3   6.7
  9750   9.5  49.1  150   8  4   9.1   5.0 |  10.7  51.3  145  11  6   9.0   5.0
  9500  10.2  50.4  150   8  4   9.9   5.5 |  11.5  52.7  145  11  6   9.9   5.4
  9250  10.9  51.6  150   8  4   9.6   5.3 |  12.2  54.0  145  11  6   9.8   5.4
  9000  11.7  53.1  150   8  4   9.6   5.3 |  12.9  55.2  145  11  5   9.9   5.4
  8750  12.4  54.3  150   8  4   9.7   5.3 |  13.7  56.7  145  10  5   9.9   5.4
  8500  13.1  55.6  150   7  4   9.5   5.2 |  14.4  57.9  145  10  5   9.7   5.3
  8250  13.8  56.8  150   7  4  10.2   5.6 |  15.1  59.2  140   9  5  10.5   5.8
  8000  14.6  58.3  150   7  4  10.3   5.6 |  15.9  60.6  140   9  5  10.1   5.5
  7750  15.4  59.7  150   7  3   9.5   5.2 |  16.6  61.9  140   8  4   8.7   4.8
  7500  16.1  61.0  150   7  3   9.4   5.2 |  17.2  63.0  135   8  4   8.7   4.8
  7250  16.8  62.2  150   6  3  10.1   5.6 |  17.9  64.2  135   8  4   9.6   5.3
  7000  17.5  63.5  150   6  3  10.6   5.8 |  18.7  65.7  130   7  4  10.3   5.7
  6750  18.3  64.9  150   6  3   9.9   5.4 |  19.4  66.9  125   6  3   9.4   5.2
  6500  19.0  66.2  150   6  3  10.0   5.5 |  20.1  68.2  125   6  3   9.3   5.1
  6250  19.8  67.6  150   6  3  10.6   5.8 |  20.8  69.4  120   5  3   9.9   5.5
  6000  20.6  69.1  150   5  3  11.1   6.1 |  21.5  70.7  110   5  2  10.2   5.6
  5750  21.4  70.5  150   5  3   9.7   5.3 |  22.3  72.1  105   4  2  10.1   5.5
  5500  22.2  72.0  155   5  2  12.6   6.9 |  23.0  73.4  095   4  2  10.2   5.6
________________________________________________________________________________

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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