Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010033
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1833 MDT Sunday, May 31, 2015

This forecast is for Monday, June 1, 2015:

If the trigger temperature of 79.7 F/26.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1068 ft/min (5.4 m/s)
   Maximum height of thermals.................. 16750 ft MSL (11443 ft AGL)

Forecast maximum temperature................... 86.0 F/30.5 C
Time of trigger temperature.................... 1115 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................. 10341 ft MSL (5034 ft AGL)
Thermal soaring outlook for Tuesday 06/02...... 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)................ Weak PVA
Potential height of wave....................... 16861 ft MSL (11554 ft AGL)
Wave soaring outlook for Tuesday 06/02......... Poor

Remarks... None

Sunrise/Sunset.................... 05:33:43 / 20:20:44 MDT
Total possible sunshine........... 14 hr 47 min 0 sec (887 min 0 sec)
Altitude of sun at 12:57:25 MDT... 72.29 degrees

Upper air data from numerical model forecast valid on 06/01/2015 at 0600 MDT

Freezing level.................. 15037 ft MSL (9730 ft AGL)
Convective condensation level... 15688 ft MSL (10381 ft AGL)
Lifted condensation level....... 15991 ft MSL (10685 ft AGL)
Lifted index.................... -3.6
K index......................... +22.6

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  -65.3 -85.5   320   22   11  -1.1  -0.6      M     M       M      M    M
 45000  -65.3 -85.5   325   25   13   4.4   2.4      M     M       M      M    M
 40000  -58.5 -73.3   290   29   15   7.4   4.0      M     M       M      M    M
 38000  -53.9 -65.0   285   29   15   7.5   4.1      M     M       M      M    M
 36000  -49.4 -56.9   280   29   15   7.5   4.1      M     M       M      M    M
 34000  -44.7 -48.5   275   25   13   8.2   4.5      M     M       M      M    M
 32000  -39.8 -39.6   275   20   10   8.2   4.5      M     M       M      M    M
 30000  -34.3 -29.7   275   16    8   8.2   4.5   40.9 105.5     8.2      M    M
 29000  -31.8 -25.2   280   15    8   8.2   4.5   40.3 104.5     7.9      M    M
 28000  -29.4 -20.9   280   14    7   8.0   4.4   39.8 103.7     7.6      M    M
 27000  -27.1 -16.8   280   13    7   7.7   4.2   38.9 102.1     6.9      M    M
 26000  -24.8 -12.6   275   12    6   7.7   4.2   38.1 100.6     6.4      M    M
 25000  -22.6  -8.7   270   12    6   7.9   4.3   37.5  99.4     5.8      M    M
 24000  -20.6  -5.1   275   12    6   6.2   3.4   36.3  97.3     4.9      M    M
 23000  -18.8  -1.8   275   13    7   6.3   3.4   35.0  94.9     3.9      M    M
 22000  -16.9   1.6   280   14    7   6.2   3.4   33.8  92.8     2.9      M    M
 21000  -14.7   5.5   280   13    7   7.8   4.3   32.9  91.3     2.2      M    M
 20000  -12.4   9.7   285   12    6   7.8   4.3   32.3  90.1     1.6      M    M
 19500  -11.2  11.8   285   11    6   7.8   4.3   32.0  89.5     1.4      M    M
 19000  -10.0  14.0   290   11    6   8.5   4.7   31.7  89.1     1.1      M    M
 18500   -8.7  16.3   300   11    6   8.7   4.8   31.5  88.7     0.9      M    M
 18000   -7.4  18.7   305   12    6   8.6   4.7   31.3  88.4     0.8      M    M
 17500   -6.2  20.8   315   12    6   7.9   4.3   31.1  87.9     0.5      M    M
 17000   -5.1  22.8   320   13    7   7.9   4.3   30.7  87.3     0.2      M    M
 16500   -3.9  25.0   320   14    7   8.2   4.5   30.5  86.8    -0.1   1054  5.4
 16000   -2.1  28.2   325   14    7   8.2   4.5   30.1  86.1    -0.4    977  5.0
 15500   -0.9  30.4   325   14    7   8.4   4.6   29.8  85.7    -0.7    926  4.7
 15000    0.4  32.7   325   14    7   8.4   4.6   29.6  85.3    -0.9    874  4.4
 14500    1.6  34.9   330   14    7   8.7   4.8   29.4  84.9    -1.1    822  4.2
 14000    2.9  37.2   330   14    7   8.9   4.9   29.2  84.6    -1.3    769  3.9
 13500    4.2  39.6   330   13    7   8.8   4.8   29.1  84.4    -1.5    715  3.6
 13000    5.5  41.9   330   13    7   8.7   4.8   28.9  84.1    -1.7    662  3.4
 12500    6.7  44.1   330   12    6   8.7   4.8   28.8  83.8    -1.8    609  3.1
 12000    8.0  46.4   330   11    6   8.6   4.7   28.6  83.5    -2.1    556  2.8
 11500    9.3  48.7   325   10    5   8.6   4.7   28.4  83.1    -2.3    504  2.6
 11000   10.5  50.9   325    9    5   8.3   4.5   28.2  82.8    -2.5    451  2.3
 10500   11.8  53.2   320    9    4   4.3   2.4   28.0  82.5    -2.7    399  2.0
 10250   11.9  53.4   320    8    4   5.4   3.0   27.4  81.4    -3.3    387  2.0
 10000   12.7  54.9   315    8    4  11.5   6.3   27.5  81.5    -3.3    357  1.8
  9750   13.4  56.1   310    8    4  10.1   5.6   27.5  81.5    -3.3    327  1.7
  9500   14.2  57.6   305    8    4   9.5   5.2   27.6  81.6    -3.2    297  1.5
  9250   14.8  58.6   305    8    4   6.4   3.5   27.4  81.4    -3.4    272  1.4
  9000   15.2  59.4   300    7    4   7.1   3.9   27.2  80.9    -3.7    251  1.3
  8750   15.8  60.4   290    7    4   8.8   4.8   27.0  80.7    -3.8    226  1.1
  8500   16.4  61.5   285    7    4   7.9   4.3   26.9  80.5    -3.9    200  1.0
  8250   17.0  62.6   280    7    4   7.2   4.0   26.8  80.2    -4.1    176  0.9
  8000   17.5  63.5   270    7    4   6.5   3.6   26.6  79.8    -4.4    154  0.8
  7750   17.9  64.2   260    8    4   5.9   3.2   26.3  79.3    -4.7    134  0.7
  7500   18.3  64.9   255    8    4   5.8   3.2   26.0  78.8    -5.0    114  0.6
  7250   18.7  65.7   245    8    4   5.8   3.2   25.7  78.2    -5.3     94  0.5
  7000   19.2  66.6   240    9    5   5.7   3.1   25.4  77.7    -5.6     74  0.4
  6750   19.5  67.1   235   10    5   4.3   2.4   25.0  77.1    -6.0     55  0.3
  6500   19.7  67.5   230   10    5  -0.5  -0.3   24.5  76.0    -6.6     44  0.2
  6250   19.4  66.9   225   10    5  -4.7  -2.6   23.5  74.3    -7.6     45  0.2
  6000   19.1  66.4   220   10    5   1.1   0.6   22.5  72.6    -8.7     47  0.2
  5750   19.1  66.4   220   11    6  -6.2  -3.4   21.9  71.4    -9.4     39  0.2
  5500   17.3  63.1   215    9    5 -40.4 -22.2   19.5  67.1   -12.0     85  0.4

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

           06/01/2015 at 0900 MDT          |       06/01/2015 at 1200 MDT
                                           |
K index... +19.9  LI... +271.6             | K index... +15.1  LI... +271.0
CAPE... +64.6  CIN... -141.7               | CAPE... +361.5  CIN... -29.6
                                           |
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 -64.6 -84.3  315  17  9  -1.1  -0.6 | -64.1 -83.4  290  15  8  -0.9  -0.5
 45000 -64.7 -84.5  315  17  9   4.1   2.3 | -64.1 -83.4  270  18  9   3.4   1.9
 40000 -58.3 -72.9  290  24 12   7.3   4.0 | -58.8 -73.8  285  24 12   7.5   4.1
 38000 -53.8 -64.8  290  23 12   7.5   4.1 | -54.1 -65.4  280  22 11   8.0   4.4
 36000 -49.3 -56.7  290  22 11   7.5   4.1 | -49.3 -56.7  275  20 10   8.0   4.4
 34000 -44.6 -48.3  290  22 11   8.2   4.5 | -44.5 -48.1  275  18  9   8.0   4.4
 32000 -39.6 -39.3  285  21 11   8.2   4.5 | -39.1 -38.4  270  14  7   7.9   4.3
 30000 -34.1 -29.4  280  18  9   8.3   4.6 | -34.4 -29.9  260  14  7   8.0   4.4
 29000 -31.6 -24.9  275  16  8   8.3   4.6 | -32.0 -25.6  255  15  8   8.0   4.4
 28000 -29.1 -20.4  265  15  8   8.1   4.5 | -29.6 -21.3  250  16  8   7.9   4.3
 27000 -26.8 -16.2  265  14  7   7.8   4.3 | -27.3 -17.1  250  16  8   7.5   4.1
 26000 -24.4 -11.9  265  14  7   7.8   4.3 | -25.1 -13.2  250  16  8   7.5   4.1
 25000 -22.1  -7.8  265  14  7   7.9   4.4 | -22.9  -9.2  255  16  8   7.6   4.2
 24000 -20.1  -4.2  265  14  7   6.7   3.7 | -20.7  -5.3  260  16  8   7.3   4.0
 23000 -18.1  -0.6  270  14  7   6.7   3.7 | -18.5  -1.3  265  16  8   7.3   4.0
 22000 -16.1   3.0  275  15  8   6.8   3.7 | -16.3   2.7  275  16  8   7.3   4.0
 21000 -14.2   6.4  275  14  7   6.3   3.4 | -14.2   6.4  275  16  8   7.3   4.0
 20000 -12.4   9.7  270  14  7   6.3   3.4 | -12.0  10.4  275  15  8   7.3   4.0
 19500 -11.5  11.3  270  13  7   6.2   3.4 | -11.0  12.2  275  15  8   7.3   4.0
 19000 -10.4  13.3  270  13  6   8.3   4.5 |  -9.9  14.2  275  14  7   7.2   4.0
 18500  -9.1  15.6  270  12  6   8.8   4.8 |  -8.8  16.2  270  13  7   7.2   4.0
 18000  -7.8  18.0  275  11  5   8.7   4.8 |  -7.7  18.1  265  12  6   7.4   4.0
 17500  -6.6  20.1  275  10  5   7.8   4.3 |  -6.5  20.3  265  11  6   8.4   4.6
 17000  -5.4  22.3  280   9  4   7.9   4.3 |  -5.3  22.5  265  10  5   8.3   4.6
 16500  -4.3  24.3  285   8  4   8.2   4.5 |  -3.4  25.9  265  10  5   8.6   4.7
 16000  -2.5  27.5  290   7  4   8.2   4.5 |  -2.1  28.2  265   9  5   8.6   4.7
 15500  -1.3  29.7  295   7  4   8.6   4.7 |  -0.9  30.4  265   9  5   8.5   4.7
 15000  -0.0  32.0  300   6  3   8.6   4.7 |   0.4  32.7  265   8  4   8.5   4.7
 14500   1.2  34.2  305   6  3   8.9   4.9 |   1.7  35.1  265   8  4   8.6   4.7
 14000   2.6  36.7  305   6  3   9.0   4.9 |   2.9  37.2  265   7  4   8.7   4.8
 13500   3.9  39.0  305   5  3   9.1   5.0 |   4.2  39.6  260   6  3   8.8   4.9
 13000   5.3  41.5  305   5  3   9.1   5.0 |   5.6  42.1  260   6  3   9.0   4.9
 12500   6.6  43.9  305   5  3   9.1   5.0 |   6.9  44.4  260   6  3   9.1   5.0
 12000   8.0  46.4  300   5  3   9.1   5.0 |   8.3  46.9  260   5  3   9.4   5.2
 11500   9.4  48.9  295   5  3   9.1   5.0 |   9.7  49.5  265   5  2   9.3   5.1
 11000  10.7  51.3  295   6  3   8.6   4.7 |  11.0  51.8  265   4  2   8.6   4.7
 10500  12.0  53.6  290   6  3   4.6   2.5 |  12.4  54.3  275   4  2   4.6   2.5
 10250  12.2  54.0  290   6  3   5.6   3.1 |  12.6  54.7  275   4  2   5.5   3.0
 10000  13.0  55.4  290   6  3  11.8   6.5 |  13.3  55.9  275   4  2  11.6   6.4
  9750  13.8  56.8  285   6  3  10.5   5.7 |  14.1  57.4  280   4  2  10.1   5.6
  9500  14.5  58.1  285   6  3   9.6   5.2 |  14.8  58.6  280   4  2   9.9   5.4
  9250  15.1  59.2  285   7  3   6.6   3.6 |  15.5  59.9  285   4  2   8.3   4.6
  9000  15.6  60.1  285   7  3   7.6   4.2 |  16.1  61.0  285   4  2   8.2   4.5
  8750  16.2  61.2  280   7  3   9.1   5.0 |  16.7  62.1  290   3  2   8.4   4.6
  8500  16.9  62.4  280   7  3   8.3   4.6 |  17.3  63.1  290   3  2   8.9   4.9
  8250  17.4  63.3  280   6  3   7.8   4.3 |  17.9  64.2  295   2  1  10.2   5.6
  8000  18.0  64.4  280   6  3   7.5   4.1 |  18.6  65.5  300   2  1  10.0   5.5
  7750  18.5  65.3  275   6  3   7.8   4.3 |  19.2  66.6  305   1  1   9.4   5.2
  7500  19.1  66.4  270   6  3   6.7   3.7 |  19.9  67.8  310   1  1   9.6   5.2
  7250  19.5  67.1  265   6  3   5.6   3.1 |  20.6  69.1  315   1  0   9.6   5.3
  7000  19.9  67.8  260   5  3   5.9   3.2 |  21.3  70.3  315   1  0   9.6   5.2
  6750  20.2  68.4  255   5  3   5.6   3.1 |  22.0  71.6  320   1  0   9.7   5.3
  6500  20.5  68.9  250   5  2   3.4   1.8 |  22.8  73.0  325   1  1  10.8   5.9
  6250  20.7  69.3  250   4  2   2.6   1.4 |  23.6  74.5  325   1  1  12.0   6.6
  6000  20.8  69.4  245   3  1   0.9   0.5 |  24.4  75.9  330   1  1  10.3   5.6
  5750  20.8  69.4  240   2  1   3.3   1.8 |  25.2  77.4  330   1  1  12.8   7.0
  5500  21.4  70.5  225   1  1  16.4   9.0 |  26.5  79.7  330   1  1  23.2  12.7

           06/01/2015 at 1500 MDT          |       06/01/2015 at 1800 MDT
                                           |
K index... +23.4  LI... +272.4             | K index... +26.7  LI... +272.0
CAPE... +72.5  CIN... -29.4                | CAPE... +63.0  CIN... -143.8
                                           |
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 -64.4 -83.9  275  18  9  -0.8  -0.4 | -63.9 -83.0  275  19 10  -0.4  -0.2
 45000 -64.3 -83.7  250  25 13   3.4   1.9 | -63.7 -82.7  255  26 13   2.1   1.1
 40000 -58.9 -74.0  260  30 16   7.8   4.3 | -60.3 -76.5  245  36 18   8.1   4.5
 38000 -54.0 -65.2  260  29 15   8.2   4.5 | -54.8 -66.6  245  33 17   9.1   5.0
 36000 -49.0 -56.2  255  27 14   8.2   4.5 | -49.4 -56.9  240  30 15   9.1   5.0
 34000 -43.5 -46.3  255  25 13   8.1   4.4 | -43.2 -45.8  240  26 13   9.1   5.0
 32000 -38.7 -37.7  255  23 12   7.9   4.4 | -37.7 -35.9  245  23 12   9.0   4.9
 30000 -33.7 -28.7  255  21 11   8.4   4.6 | -32.6 -26.7  250  19 10   8.3   4.5
 29000 -31.2 -24.2  255  21 11   8.4   4.6 | -30.2 -22.4  255  18  9   8.3   4.5
 28000 -28.7 -19.7  255  21 11   8.0   4.4 | -27.7 -17.9  260  17  9   7.9   4.3
 27000 -26.5 -15.7  255  20 10   7.3   4.0 | -25.6 -14.1  265  16  8   6.9   3.8
 26000 -24.4 -11.9  260  20 10   7.3   4.0 | -23.6 -10.5  270  15  8   6.9   3.8
 25000 -22.2  -8.0  265  20 10   7.4   4.0 | -21.5  -6.7  275  15  8   6.9   3.8
 24000 -20.1  -4.2  270  19 10   7.0   3.8 | -19.5  -3.1  285  15  8   7.1   3.9
 23000 -18.0  -0.4  275  18  9   7.0   3.8 | -17.4   0.7  290  15  8   7.1   3.9
 22000 -16.0   3.2  280  18  9   7.0   3.8 | -15.3   4.5  295  16  8   7.2   3.9
 21000 -13.8   7.2  285  18  9   7.4   4.0 | -13.3   8.1  305  15  8   6.5   3.6
 20000 -11.7  10.9  290  19 10   7.4   4.0 | -11.4  11.5  315  15  7   6.5   3.6
 19500 -10.6  12.9  290  19 10   7.4   4.0 | -10.4  13.3  315  14  7   6.6   3.6
 19000  -9.5  14.9  295  19 10   7.8   4.3 |  -9.5  14.9  320  14  7   7.0   3.9
 18500  -8.3  17.1  295  19 10   8.0   4.4 |  -8.4  16.9  330  12  6   7.3   4.0
 18000  -7.1  19.2  295  18  9   8.0   4.4 |  -6.8  19.8  350   9  5   7.3   4.0
 17500  -5.9  21.4  295  17  9   8.2   4.5 |  -5.8  21.6  010   7  3   7.3   4.0
 17000  -4.1  24.6  295  15  8   8.2   4.5 |  -4.7  23.5  040   6  3   7.3   4.0
 16500  -2.9  26.8  295  13  7   8.1   4.4 |  -3.7  25.3  060   5  3   6.6   3.6
 16000  -1.7  28.9  290  12  6   8.1   4.4 |  -2.7  27.1  080   6  3   6.6   3.6
 15500  -0.5  31.1  290  10  5   8.3   4.5 |  -1.7  28.9  090   6  3   7.9   4.3
 15000   0.7  33.3  280   8  4   8.3   4.5 |  -0.5  31.1  095   6  3   8.0   4.4
 14500   2.0  35.6  270   6  3   8.6   4.7 |   0.6  33.1  100   5  3   9.2   5.0
 14000   3.3  37.9  260   5  2   8.8   4.8 |   2.1  35.8  105   5  3  10.0   5.5
 13500   4.6  40.3  240   4  2   8.7   4.8 |   3.6  38.5  110   5  2   9.9   5.4
 13000   5.9  42.6  220   3  2   8.5   4.7 |   5.1  41.2  120   4  2   9.7   5.3
 12500   7.2  45.0  200   3  2   8.6   4.7 |   6.5  43.7  130   3  2   9.5   5.2
 12000   8.5  47.3  190   3  2   9.2   5.0 |   7.9  46.2  160   3  2   8.4   4.6
 11500   9.8  49.6  180   3  2   9.2   5.1 |   9.1  48.4  190   3  2   8.4   4.6
 11000  11.2  52.2  175   3  2   9.4   5.2 |  10.4  50.7  210   5  2   8.1   4.4
 10500  12.6  54.7  175   3  2   6.3   3.5 |  11.6  52.9  220   7  4   4.8   2.6
 10250  12.9  55.2  175   3  2   7.4   4.1 |  11.8  53.2  225   7  4   5.2   2.8
 10000  13.8  56.8  175   3  2  12.4   6.8 |  12.5  54.5  225   9  4  10.1   5.6
  9750  14.6  58.3  175   3  2  11.3   6.2 |  13.2  55.8  230  10  5   9.1   5.0
  9500  15.5  59.9  175   3  2  10.8   5.9 |  13.9  57.0  230  12  6   9.0   4.9
  9250  16.2  61.2  175   3  1   8.9   4.9 |  14.4  57.9  230  13  7   6.9   3.8
  9000  16.9  62.4  175   3  1   9.8   5.4 |  14.9  58.8  230  14  7   6.7   3.7
  8750  17.6  63.7  175   3  1  10.9   6.0 |  15.4  59.7  235  16  8   7.8   4.3
  8500  18.4  65.1  175   3  1  10.3   5.7 |  16.0  60.8  235  18  9   7.1   3.9
  8250  19.2  66.6  175   3  1   9.9   5.4 |  16.5  61.7  235  19 10   6.2   3.4
  8000  19.9  67.8  180   3  1   9.6   5.3 |  16.9  62.4  235  21 11   5.8   3.2
  7750  20.6  69.1  180   3  1   9.3   5.1 |  17.3  63.1  235  23 12   6.1   3.3
  7500  21.3  70.3  180   2  1  10.0   5.5 |  17.7  63.9  235  24 13   5.3   2.9
  7250  22.1  71.8  180   2  1  11.2   6.1 |  18.0  64.4  235  26 13   4.4   2.4
  7000  23.0  73.4  180   2  1  10.7   5.9 |  18.3  64.9  235  27 14   4.4   2.4
  6750  23.7  74.7  180   2  1   9.0   5.0 |  18.6  65.5  235  28 15   4.3   2.4
  6500  24.4  75.9  180   2  1   9.9   5.4 |  19.0  66.2  235  29 15   6.5   3.6
  6250  25.2  77.4  185   2  1  11.5   6.3 |  19.5  67.1  235  28 14   8.6   4.7
  6000  26.0  78.8  185   2  1  10.2   5.6 |  20.0  68.0  235  26 14   7.2   4.0
  5750  26.8  80.2  190   2  1  12.3   6.7 |  20.6  69.1  235  25 13   9.8   5.4
  5500  28.0  82.4  190   2  1  21.5  11.8 |  21.5  70.7  235  22 11  17.7   9.7
________________________________________________________________________________

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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