Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010044
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1844 MDT Monday, August 31, 2015

This forecast is for Tuesday, September 1, 2015:

If the trigger temperature of 79.2 F/26.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1002 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16401 ft MSL (11094 ft AGL)

Forecast maximum temperature................... 87.0 F/31.0 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11253 ft MSL (5946 ft AGL)
Thermal soaring outlook for Wednesday 09/02.... 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)................ Neither
Potential height of wave....................... 23004 ft MSL (17697 ft AGL)
Wave soaring outlook for Wednesday 09/02....... Poor

Remarks... None

Sunrise/Sunset.................... 06:27:17 / 19:32:25 MDT
Total possible sunshine........... 13 hr 5 min 8 sec (785 min 8 sec)
Altitude of sun at 12:59:25 MDT... 58.41 degrees

Upper air data from numerical model forecast valid on 09/01/2015 at 0600 MDT

Freezing level.................. 15163 ft MSL (9856 ft AGL)
Convective condensation level... 14876 ft MSL (9569 ft AGL)
Lifted condensation level....... 15450 ft MSL (10143 ft AGL)
Lifted index.................... -1.5
K index......................... +20.4

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  -64.8 -84.6   255   33   17   0.3   0.2      M     M       M      M    M
 45000  -62.1 -79.8   260   41   21   4.9   2.7      M     M       M      M    M
 40000  -54.3 -65.7   255   45   23   7.4   4.1      M     M       M      M    M
 38000  -49.8 -57.6   255   44   23   7.5   4.1      M     M       M      M    M
 36000  -45.3 -49.5   255   43   22   7.5   4.1      M     M       M      M    M
 34000  -40.7 -41.3   250   40   20   7.9   4.3      M     M       M      M    M
 32000  -36.0 -32.8   245   37   19   7.8   4.3      M     M       M      M    M
 30000  -30.1 -22.2   240   34   17   9.0   5.0   45.7 114.3    11.5      M    M
 29000  -27.4 -17.3   240   32   17   9.0   5.0   45.5 113.9    11.4      M    M
 28000  -24.8 -12.6   240   31   16   7.4   4.0   45.2 113.4    11.4      M    M
 27000  -22.7  -8.9   240   29   15   7.0   3.8   44.0 111.3    10.5      M    M
 26000  -20.6  -5.1   240   27   14   7.0   3.9   43.0 109.4     9.8      M    M
 25000  -18.6  -1.5   240   26   13   7.0   3.8   42.1 107.8     9.1      M    M
 24000  -16.7   1.9   240   24   12   6.1   3.3   40.7 105.3     8.1      M    M
 23000  -14.9   5.2   240   22   11   6.1   3.3   39.4 102.9     7.0      M    M
 22000  -13.1   8.4   245   21   11   6.0   3.3   38.2 100.7     6.1      M    M
 21000  -11.4  11.5   250   19   10   5.7   3.1   36.7  98.0     4.9      M    M
 20000   -9.7  14.5   255   18    9   5.7   3.1   35.3  95.5     3.7      M    M
 19500   -8.9  16.0   255   17    9   5.7   3.1   34.6  94.3     3.1      M    M
 19000   -8.0  17.6   260   17    9   6.6   3.6   34.0  93.2     2.6      M    M
 18500   -7.0  19.4   260   17    9   6.6   3.6   33.4  92.2     2.1      M    M
 18000   -6.0  21.2   260   16    8   6.6   3.6   32.9  91.3     1.7      M    M
 17500   -5.0  23.0   260   16    8   6.4   3.5   32.3  90.2     1.2      M    M
 17000   -4.1  24.6   265   15    8   6.4   3.5   31.8  89.2     0.7      M    M
 16500   -3.1  26.4   265   15    8   7.0   3.9   31.3  88.3     0.2      M    M
 16000   -2.1  28.2   265   14    7   7.1   3.9   30.8  87.4    -0.3    977  5.0
 15500   -0.5  31.1   270   13    7   8.0   4.4   30.2  86.4    -0.8    906  4.6
 15000    0.6  33.1   270   12    6   7.9   4.4   29.9  85.8    -1.2    857  4.4
 14500    1.8  35.2   270   11    6   8.2   4.5   29.6  85.3    -1.4    807  4.1
 14000    3.0  37.4   275   11    5   8.2   4.5   29.4  84.9    -1.7    757  3.8
 13500    4.2  39.6   275   10    5   8.4   4.6   29.1  84.4    -2.0    706  3.6
 13000    5.4  41.7   280    9    5   8.5   4.7   28.9  84.1    -2.2    654  3.3
 12500    6.7  44.1   280    9    5   8.6   4.7   28.7  83.7    -2.4    602  3.1
 12000    7.9  46.2   285    9    5   8.7   4.8   28.5  83.4    -2.7    550  2.8
 11500    9.2  48.6   285    9    5   8.6   4.7   28.4  83.1    -2.9    498  2.5
 11000   10.4  50.7   285    9    4   8.0   4.4   28.2  82.7    -3.2    447  2.3
 10500   11.5  52.7   290    9    4   4.5   2.5   27.9  82.3    -3.5    397  2.0
 10250   11.7  53.1   290    9    5   5.6   3.1   27.4  81.3    -4.0    384  1.9
 10000   12.5  54.5   290    9    5  11.0   6.0   27.4  81.3    -4.0    355  1.8
  9750   13.2  55.8   290    9    5   9.9   5.4   27.4  81.3    -4.0    325  1.7
  9500   13.9  57.0   290    9    5   9.0   4.9   27.4  81.4    -4.0    296  1.5
  9250   14.5  58.1   290    9    4   6.7   3.7   27.3  81.1    -4.2    273  1.4
  9000   15.0  59.0   290    9    4   7.8   4.3   27.0  80.7    -4.5    250  1.3
  8750   15.6  60.1   290    9    4   9.1   5.0   27.0  80.5    -4.6    224  1.1
  8500   16.2  61.2   290    9    5   8.1   4.5   26.9  80.4    -4.7    197  1.0
  8250   16.8  62.2   290    9    4   7.2   4.0   26.7  80.1    -4.9    173  0.9
  8000   17.3  63.1   295    9    4   7.3   4.0   26.5  79.7    -5.1    150  0.8
  7750   17.9  64.2   290    8    4   7.8   4.3   26.3  79.4    -5.3    127  0.6
  7500   18.4  65.1   290    8    4   6.5   3.6   26.2  79.1    -5.5    103  0.5
  7250   18.8  65.8   290    8    4   5.3   2.9   25.8  78.5    -5.8     84  0.4
  7000   19.1  66.4   290    8    4   5.8   3.2   25.5  77.9    -6.2     66  0.3
  6750   19.5  67.1   285    7    4   4.5   2.5   25.2  77.4    -6.6     47  0.2
  6500   19.7  67.5   280    7    4   1.1   0.6   24.7  76.4    -7.2     35  0.2
  6250   19.6  67.3   270    6    3  -1.5  -0.8   23.9  75.0    -8.0     30  0.2
  6000   19.5  67.1   260    6    3   2.6   1.4   23.1  73.6    -8.9     26  0.1
  5750   19.6  67.3   250    6    3  -3.0  -1.6   22.6  72.7    -9.5     15  0.1
  5500   18.4  65.1   230    5    2 -24.6 -13.5   20.8  69.5   -11.4     43  0.2

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

           09/01/2015 at 0900 MDT          |       09/01/2015 at 1200 MDT
                                           |
K index... +22.7  LI... -0.4               | K index... +22.7  LI... -1.0
CAPE... 0.0  CIN... -1.2                   | CAPE... +34.1  CIN... -43.9
                                           |
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 -64.4 -83.9  260  29 15   0.4   0.2 | -64.1 -83.4  250  25 13   1.0   0.6
 45000 -61.9 -79.4  260  40 21   4.8   2.6 | -61.1 -78.0  250  40 21   4.1   2.3
 40000 -54.3 -65.7  255  50 26   7.4   4.1 | -54.4 -65.9  255  56 29   7.7   4.2
 38000 -49.8 -57.6  255  47 24   7.5   4.1 | -49.7 -57.5  255  55 28   7.8   4.3
 36000 -45.3 -49.5  250  44 23   7.5   4.1 | -45.0 -49.0  250  53 27   7.8   4.3
 34000 -40.7 -41.3  245  41 21   7.7   4.2 | -40.4 -40.7  250  48 25   7.7   4.2
 32000 -36.1 -33.0  240  39 20   7.5   4.1 | -35.7 -32.3  245  43 22   7.6   4.2
 30000 -30.6 -23.1  235  36 19   8.4   4.6 | -30.8 -23.4  245  38 19   7.3   4.0
 29000 -28.1 -18.6  240  35 18   8.4   4.6 | -28.6 -19.5  245  35 18   7.3   4.0
 28000 -25.6 -14.1  240  34 17   7.5   4.1 | -26.4 -15.5  245  33 17   7.6   4.2
 27000 -23.5 -10.3  240  30 16   7.2   4.0 | -24.2 -11.6  245  31 16   7.7   4.2
 26000 -21.4  -6.5  240  27 14   7.2   4.0 | -21.9  -7.4  245  28 15   7.7   4.2
 25000 -19.2  -2.6  245  24 12   7.2   3.9 | -19.6  -3.3  245  26 13   7.7   4.2
 24000 -17.3   0.9  245  22 11   6.3   3.4 | -17.5   0.5  245  24 12   6.7   3.7
 23000 -15.5   4.1  245  19 10   6.3   3.4 | -15.5   4.1  245  21 11   6.7   3.7
 22000 -13.7   7.3  245  17  9   6.3   3.4 | -13.5   7.7  245  18  9   6.6   3.6
 21000 -11.8  10.8  245  16  8   6.2   3.4 | -11.7  10.9  250  16  8   6.2   3.4
 20000 -10.0  14.0  250  16  8   6.2   3.4 |  -9.9  14.2  250  15  7   6.2   3.4
 19500  -9.1  15.6  250  15  8   6.1   3.3 |  -9.0  15.8  250  14  7   6.2   3.4
 19000  -8.1  17.4  255  15  8   7.2   3.9 |  -8.1  17.4  255  13  7   6.9   3.8
 18500  -7.0  19.4  260  14  7   7.2   4.0 |  -7.0  19.4  255  12  6   6.9   3.8
 18000  -5.9  21.4  265  13  7   7.0   3.9 |  -6.0  21.2  255  12  6   7.0   3.8
 17500  -5.0  23.0  265  12  6   6.5   3.6 |  -4.9  23.2  260  11  5   7.2   4.0
 17000  -4.0  24.8  270  11  6   6.5   3.6 |  -3.9  25.0  260  10  5   7.2   4.0
 16500  -3.0  26.6  275  10  5   6.8   3.7 |  -2.3  27.9  270   8  4   6.8   3.8
 16000  -1.6  29.1  275   9  5   6.8   3.7 |  -1.4  29.5  270   8  4   6.8   3.8
 15500  -0.5  31.1  280   9  4   7.6   4.2 |  -0.3  31.5  275   7  4   7.4   4.1
 15000   0.5  32.9  280   8  4   7.5   4.1 |   0.8  33.4  280   7  4   7.4   4.0
 14500   1.6  34.9  285   7  4   7.6   4.2 |   1.8  35.2  285   6  3   7.6   4.1
 14000   2.7  36.9  290   7  4   7.6   4.2 |   2.9  37.2  285   6  3   7.6   4.2
 13500   3.8  38.8  295   7  3   7.8   4.3 |   4.1  39.4  290   6  3   7.7   4.2
 13000   5.0  41.0  300   6  3   8.0   4.4 |   5.2  41.4  300   5  3   7.7   4.2
 12500   6.1  43.0  310   6  3   8.1   4.5 |   6.3  43.3  305   5  3   8.1   4.5
 12000   7.3  45.1  320   7  3   8.4   4.6 |   7.6  45.7  310   5  3   8.7   4.8
 11500   8.6  47.5  325   7  4   8.5   4.7 |   8.8  47.8  315   5  3   8.8   4.8
 11000   9.8  49.6  330   7  4   8.4   4.6 |  10.2  50.4  325   6  3   8.7   4.8
 10500  11.1  52.0  330   8  4   4.2   2.3 |  11.5  52.7  335   6  3   4.3   2.4
 10250  11.3  52.3  335   8  4   5.8   3.2 |  11.6  52.9  335   6  3   5.5   3.0
 10000  12.1  53.8  330   8  4  12.5   6.9 |  12.4  54.3  340   6  3  12.4   6.8
  9750  12.9  55.2  330   9  4  11.2   6.1 |  13.2  55.8  340   6  3  11.0   6.0
  9500  13.7  56.7  330   9  5   9.8   5.4 |  14.0  57.2  340   6  3   9.7   5.3
  9250  14.3  57.7  330   9  5   7.1   3.9 |  14.6  58.3  340   5  3   7.8   4.3
  9000  14.8  58.6  330   9  5   8.9   4.9 |  15.2  59.4  335   5  3   9.7   5.3
  8750  15.6  60.1  330   9  5  10.5   5.8 |  16.0  60.8  335   5  2  10.7   5.9
  8500  16.3  61.3  330   9  5   9.2   5.1 |  16.7  62.1  330   4  2  10.1   5.5
  8250  16.9  62.4  325   9  5   8.3   4.6 |  17.4  63.3  330   4  2   9.5   5.2
  8000  17.5  63.5  325   9  5   8.0   4.4 |  18.2  64.8  330   4  2   9.9   5.4
  7750  18.1  64.6  320   9  5   7.6   4.2 |  18.9  66.0  330   4  2  10.2   5.6
  7500  18.7  65.7  320   9  5   7.2   3.9 |  19.7  67.5  330   4  2  10.1   5.5
  7250  19.2  66.6  315   9  5   6.9   3.8 |  20.4  68.7  330   4  2  10.1   5.5
  7000  19.7  67.5  310   9  5   6.8   3.7 |  21.2  70.2  330   4  2   9.9   5.4
  6750  20.2  68.4  305   9  4   5.6   3.1 |  21.9  71.4  325   4  2  10.0   5.5
  6500  20.6  69.1  300   8  4   4.3   2.4 |  22.7  72.9  325   4  2  10.7   5.9
  6250  20.9  69.6  295   7  4   4.8   2.6 |  23.5  74.3  325   4  2  11.6   6.4
  6000  21.1  70.0  285   7  3   2.5   1.4 |  24.3  75.7  325   4  2   9.6   5.3
  5750  21.3  70.3  275   6  3   5.0   2.7 |  25.1  77.2  325   4  2  14.1   7.7
  5500  22.0  71.6  260   5  3  16.4   9.0 |  26.6  79.9  325   4  2  27.5  15.1

           09/01/2015 at 1500 MDT          |       09/01/2015 at 1800 MDT
                                           |
K index... +21.4  LI... -1.3               | K index... +23.0  LI... -0.2
CAPE... +45.8  CIN... -51.0                | CAPE... +3.5  CIN... -11.2
                                           |
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 -64.1 -83.4  245  28 15   1.6   0.9 | -64.8 -84.6  250  35 18   1.5   0.8
 45000 -60.6 -77.1  250  45 23   3.9   2.1 | -61.3 -78.3  260  55 28   4.0   2.2
 40000 -54.2 -65.6  255  66 34   7.3   4.0 | -54.7 -66.5  255  73 38   7.6   4.2
 38000 -49.8 -57.6  255  62 32   7.4   4.1 | -50.0 -58.0  255  68 35   7.7   4.2
 36000 -45.3 -49.5  250  58 30   7.3   4.0 | -45.4 -49.7  255  62 32   7.6   4.2
 34000 -40.6 -41.1  250  51 26   8.1   4.4 | -40.4 -40.7  250  52 27   8.4   4.6
 32000 -35.1 -31.2  250  43 22   8.7   4.8 | -34.8 -30.6  250  41 21   9.0   5.0
 30000 -30.4 -22.7  250  34 18   7.9   4.3 | -29.9 -21.8  245  32 16   8.2   4.5
 29000 -28.0 -18.4  255  29 15   7.9   4.4 | -27.5 -17.5  245  27 14   8.2   4.5
 28000 -25.7 -14.3  255  25 13   7.3   4.0 | -25.1 -13.2  245  22 12   7.2   3.9
 27000 -23.6 -10.5  255  22 11   7.1   3.9 | -23.1  -9.6  250  20 10   7.0   3.8
 26000 -21.5  -6.7  255  20 10   7.1   3.9 | -21.0  -5.8  255  17  9   7.0   3.8
 25000 -19.4  -2.9  255  17  9   7.0   3.9 | -18.9  -2.0  260  15  8   7.0   3.8
 24000 -17.6   0.3  255  16  8   6.1   3.4 | -17.0   1.4  270  14  7   6.6   3.6
 23000 -15.8   3.6  255  14  7   6.2   3.4 | -15.1   4.8  275  13  7   6.6   3.6
 22000 -13.9   7.0  260  13  7   6.2   3.4 | -13.1   8.4  285  13  7   6.5   3.6
 21000 -12.1  10.2  260  12  6   6.4   3.5 | -11.3  11.7  290  12  6   6.1   3.3
 20000 -10.2  13.6  260  10  5   6.4   3.5 |  -9.6  14.7  295  12  6   6.1   3.4
 19500  -9.3  15.3  260  10  5   6.4   3.5 |  -8.7  16.3  300  11  6   6.1   3.3
 19000  -8.3  17.1  260   9  5   6.9   3.8 |  -7.8  18.0  305  11  6   6.4   3.5
 18500  -7.3  18.9  260   9  5   7.0   3.8 |  -6.8  19.8  305  11  5   6.4   3.5
 18000  -6.3  20.7  260   9  4   7.2   4.0 |  -5.9  21.4  305  10  5   6.4   3.5
 17500  -5.1  22.8  260   8  4   8.0   4.4 |  -4.9  23.2  305   9  5   6.4   3.5
 17000  -3.9  25.0  260   8  4   7.9   4.3 |  -4.0  24.8  305   9  4   6.3   3.5
 16500  -2.1  28.2  270   8  4   8.2   4.5 |  -2.5  27.5  310   7  4   7.4   4.1
 16000  -0.9  30.4  275   7  4   8.2   4.5 |  -1.4  29.5  315   6  3   7.3   4.0
 15500   0.3  32.5  285   7  4   8.3   4.5 |  -0.2  31.6  315   5  3   8.4   4.6
 15000   1.6  34.9  290   7  3   8.3   4.5 |   1.0  33.8  315   4  2   8.3   4.5
 14500   2.8  37.0  295   6  3   7.9   4.4 |   2.2  36.0  315   2  1   8.6   4.7
 14000   4.0  39.2  295   5  3   7.9   4.3 |   3.5  38.3  315   2  1   8.6   4.7
 13500   5.1  41.2  300   4  2   7.9   4.3 |   4.8  40.6  315   1  0   8.6   4.7
 13000   6.3  43.3  300   3  2   8.0   4.4 |   6.1  43.0  000   0  0   8.6   4.7
 12500   7.5  45.5  300   2  1   8.1   4.5 |   7.4  45.3  185   1  1   8.8   4.8
 12000   8.6  47.5  295   2  1   8.4   4.6 |   8.7  47.7  185   2  1   9.1   5.0
 11500   9.8  49.6  285   2  1   8.5   4.7 |  10.1  50.2  185   3  1   9.0   4.9
 11000  11.1  52.0  275   2  1   8.6   4.7 |  11.4  52.5  195   3  2   8.5   4.6
 10500  12.3  54.1  265   2  1   5.2   2.8 |  12.7  54.9  200   4  2   4.1   2.3
 10250  12.6  54.7  260   2  1   6.7   3.7 |  12.9  55.2  200   4  2   5.5   3.0
 10000  13.4  56.1  260   2  1  12.4   6.8 |  13.7  56.7  205   4  2  12.3   6.8
  9750  14.2  57.6  260   2  1  11.3   6.2 |  14.5  58.1  210   5  2  10.9   6.0
  9500  15.0  59.0  260   2  1  10.2   5.6 |  15.3  59.5  210   5  3   9.9   5.4
  9250  15.7  60.3  260   2  1   8.4   4.6 |  16.0  60.8  215   5  3   7.8   4.3
  9000  16.4  61.5  260   2  1   9.9   5.4 |  16.6  61.9  220   6  3   9.4   5.2
  8750  17.1  62.8  260   2  1  10.6   5.8 |  17.4  63.3  220   6  3  10.6   5.8
  8500  17.9  64.2  260   2  1  10.5   5.8 |  18.2  64.8  225   7  3   9.6   5.3
  8250  18.7  65.7  260   2  1  11.1   6.1 |  18.8  65.8  230   7  4   8.6   4.7
  8000  19.5  67.1  260   2  1  10.2   5.6 |  19.5  67.1  235   8  4   8.6   4.7
  7750  20.2  68.4  260   2  1   9.2   5.1 |  20.1  68.2  240   9  5   8.9   4.9
  7500  21.0  69.8  260   2  1   9.9   5.4 |  20.8  69.4  240  10  5   8.1   4.4
  7250  21.7  71.1  265   2  1  10.4   5.7 |  21.3  70.3  245  11  6   7.3   4.0
  7000  22.5  72.5  265   2  1  10.0   5.5 |  21.8  71.2  245  12  6   7.4   4.1
  6750  23.2  73.8  265   3  1   9.9   5.4 |  22.3  72.1  245  14  7   6.4   3.5
  6500  24.0  75.2  265   3  1  10.5   5.8 |  22.7  72.9  250  15  8   4.5   2.5
  6250  24.8  76.6  265   3  1  11.5   6.3 |  22.9  73.2  250  15  8   4.2   2.3
  6000  25.6  78.1  265   3  1   9.6   5.2 |  23.1  73.6  250  16  8   3.2   1.8
  5750  26.4  79.5  265   3  2  13.5   7.4 |  23.2  73.8  250  16  8   6.2   3.4
  5500  27.9  82.2  265   3  1  26.6  14.6 |  24.0  75.2  250  14  7  16.1   8.8
________________________________________________________________________________

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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