Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 200102
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1902 MDT Friday, September 19, 2014

This forecast is for Saturday, September 20, 2014:

If the trigger temperature of 77.4 F/25.2 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 464 ft/min (2.4 m/s)
   Maximum height of thermals.................. 9109 ft MSL (3822 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1445 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................. 7270 ft MSL (1982 ft AGL)
Thermal soaring outlook for Sunday 09/21....... 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 NVA
Potential height of wave....................... 16837 ft MSL (11550 ft AGL)
Wave soaring outlook for Sunday 09/21.......... Fair

Remarks... Upper level ridge over colorado Saturday with weak winds aloft. Low
           level northeasterly winds and building high surface pressure.

Sunrise/Sunset.................... 06:45:14 / 19:01:21 MDT
Total possible sunshine........... 12 hr 16 min 7 sec (736 min 7 sec)
Altitude of sun at 12:52:47 MDT... 51.14 degrees

Upper air data from numerical model forecast valid on 09/20/2014 at 0600 MDT

Freezing level.................. 14781 ft MSL (9494 ft AGL)
Convective condensation level... 14357 ft MSL (9070 ft AGL)
Lifted condensation level....... 13199 ft MSL (7912 ft AGL)
Lifted index.................... +0.8
K index......................... +27.0

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  -67.5 -89.5   290   56   29   2.8   1.5      M     M       M      M    M
 45000  -61.5 -78.7   285   76   39   6.9   3.8      M     M       M      M    M
 40000  -50.8 -59.4   285   80   41   6.3   3.4      M     M       M      M    M
 38000  -47.1 -52.8   290   70   36   6.3   3.4      M     M       M      M    M
 36000  -43.3 -45.9   290   61   31   6.4   3.5      M     M       M      M    M
 34000  -40.1 -40.2   290   49   25   5.2   2.8      M     M       M      M    M
 32000  -37.0 -34.6   295   36   18   5.2   2.8      M     M       M      M    M
 30000  -32.8 -27.0   295   29   15   7.6   4.2   43.2 109.8    13.9      M    M
 29000  -30.0 -22.0   295   26   13   7.6   4.2   42.2 108.0    13.3      M    M
 28000  -27.7 -17.9   295   23   12   8.2   4.5   41.6 106.8    12.9      M    M
 27000  -25.2 -13.4   300   22   11   8.3   4.6   40.9 105.6    12.5      M    M
 26000  -22.7  -8.9   305   21   11   8.3   4.6   40.4 104.6    12.3      M    M
 25000  -20.2  -4.4   310   20   10   8.2   4.5   39.9 103.9    12.1      M    M
 24000  -17.8  -0.0   315   19   10   7.9   4.4   39.2 102.5    11.6      M    M
 23000  -15.4   4.3   320   18    9   7.9   4.4   38.5 101.3    11.2      M    M
 22000  -13.0   8.6   325   17    9   7.8   4.3   38.0 100.3    10.8      M    M
 21000  -10.8  12.6   325   16    8   7.5   4.1   37.1  98.7    10.2      M    M
 20000   -8.6  16.5   325   16    8   7.5   4.1   36.3  97.3     9.6      M    M
 19500   -7.5  18.5   325   16    8   7.6   4.2   35.9  96.7     9.4      M    M
 19000   -6.4  20.5   325   15    8   6.1   3.3   35.5  95.8     9.0      M    M
 18500   -5.5  22.1   320   15    8   6.2   3.4   34.8  94.7     8.5      M    M
 18000   -4.6  23.7   315   15    8   5.6   3.1   34.3  93.7     8.0      M    M
 17500   -4.0  24.8   310   15    8   4.7   2.6   33.4  92.1     7.2      M    M
 17000   -3.3  26.1   300   15    8   5.1   2.8   32.6  90.6     6.4      M    M
 16500   -2.7  27.1   295   14    7   4.9   2.7   31.7  89.1     5.6      M    M
 16000   -2.1  28.2   290   12    6   5.2   2.8   30.9  87.7     4.8      M    M
 15500   -1.5  29.3   285   11    6   6.0   3.3   30.2  86.4     4.0      M    M
 15000   -0.6  30.9   280    9    5   6.4   3.5   29.6  85.4     3.4      M    M
 14500    0.9  33.6   265    6    3   8.6   4.7   29.0  84.1     2.7      M    M
 14000    2.1  35.8   270    5    2   8.7   4.8   28.8  83.8     2.5      M    M
 13500    3.4  38.1   275    3    2   8.4   4.6   28.6  83.5     2.4      M    M
 13000    4.6  40.3   315    3    1   8.3   4.6   28.4  83.0     2.1      M    M
 12500    5.8  42.4   350    3    2   8.6   4.7   28.1  82.7     1.9      M    M
 12000    7.1  44.8   355    4    2   8.9   4.9   28.0  82.4     1.7      M    M
 11500    8.4  47.1   360    5    3   8.7   4.8   27.9  82.2     1.6      M    M
 11000    9.7  49.5   360    7    3   8.2   4.5   27.7  81.8     1.4      M    M
 10500   11.0  51.8   005    8    4   4.3   2.3   27.5  81.5     1.2      M    M
 10250   11.1  52.0   005    8    4   3.8   2.1   26.9  80.3     0.7      M    M
 10000   11.7  53.1   010    9    5   9.3   5.1   26.7  80.1     0.5      M    M
  9750   12.4  54.3   010   10    5   8.9   4.9   26.6  79.9     0.5      M    M
  9500   13.1  55.6   010   10    5   7.4   4.1   26.6  79.8     0.5      M    M
  9250   13.5  56.3   010   10    5   5.6   3.1   26.3  79.3     0.1      M    M
  9000   13.9  57.0   010   10    5   7.8   4.3   26.0  78.8    -0.2    253  1.3
  8750   14.5  58.1   010    9    5   9.4   5.2   25.9  78.7    -0.3    227  1.2
  8500   15.1  59.2   010   10    5   5.9   3.2   25.8  78.5    -0.5    203  1.0
  8250   15.4  59.7   010   11    6   3.7   2.1   25.4  77.7    -0.8    185  0.9
  8000   15.8  60.4   010   12    6   3.2   1.8   24.9  76.9    -1.2    167  0.8
  7750   16.0  60.8   010   14    7   1.4   0.8   24.4  75.8    -1.7    154  0.8
  7500   16.1  61.0   010   16    8   2.0   1.1   23.7  74.7    -2.4    144  0.7
  7250   16.1  61.0   010   18    9   2.6   1.4   23.2  73.7    -3.0    134  0.7
  7000   16.2  61.2   010   20   10   2.2   1.2   22.6  72.7    -3.7    125  0.6
  6750   16.2  61.2   010   22   11   1.3   0.7   22.0  71.6    -4.5    118  0.6
  6500   16.3  61.3   010   22   11   1.3   0.7   21.4  70.4    -5.1    107  0.5
  6250   16.5  61.7   005   21   11   1.4   0.8   20.7  69.3    -5.7     94  0.5
  6000   16.6  61.9   360   21   11   1.9   1.0   20.1  68.2    -6.2     82  0.4
  5750   16.8  62.2   355   18    9   0.7   0.4   19.5  67.1    -6.8     71  0.4
  5500   16.7  62.1   350   12    6  -2.8  -1.5   18.7  65.7    -7.6     66  0.3

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

           09/20/2014 at 0900 MDT          |       09/20/2014 at 1200 MDT
                                           |
K index... +22.0  LI... 0.0                | K index... +19.6  LI... -0.1
CAPE... +274.1  CIN... -65.9               | CAPE... +229.6  CIN... -90.6
                                           |
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 -67.6 -89.7  290  52 27   2.8   1.5 | -67.8 -90.0  285  51 26   2.5   1.4
 45000 -61.7 -79.1  285  71 37   6.7   3.7 | -62.2 -80.0  285  68 35   6.7   3.7
 40000 -51.1 -60.0  290  76 39   7.1   3.9 | -51.5 -60.7  290  72 37   7.3   4.0
 38000 -46.8 -52.2  290  69 36   7.1   3.9 | -47.1 -52.8  290  66 34   7.3   4.0
 36000 -42.6 -44.7  295  62 32   7.3   4.0 | -42.7 -44.9  290  61 31   7.4   4.1
 34000 -39.3 -38.7  295  47 24   5.2   2.9 | -39.3 -38.7  290  44 23   5.6   3.1
 32000 -36.1 -33.0  300  31 16   5.2   2.9 | -35.9 -32.6  295  27 14   5.5   3.0
 30000 -32.3 -26.1  300  22 11   6.7   3.7 | -32.1 -25.8  300  17  9   6.7   3.7
 29000 -29.8 -21.6  305  18  9   6.7   3.7 | -29.5 -21.1  305  13  7   6.7   3.7
 28000 -27.7 -17.9  310  15  8   8.2   4.5 | -27.5 -17.5  315   9  5   7.8   4.3
 27000 -25.2 -13.4  315  13  7   8.3   4.5 | -25.1 -13.2  320   6  3   7.8   4.3
 26000 -22.7  -8.9  330  11  6   8.3   4.5 | -22.8  -9.0  335   3  1   7.8   4.3
 25000 -20.2  -4.4  345  10  5   8.3   4.6 | -20.5  -4.9  060   2  1   8.1   4.5
 24000 -17.7   0.1  345   9  5   8.3   4.6 | -17.9  -0.2  035   1  0   8.6   4.7
 23000 -15.3   4.5  345   9  4   8.3   4.6 | -15.3   4.5  290   1  0   8.6   4.7
 22000 -12.8   9.0  345   8  4   8.0   4.4 | -12.8   9.0  275   2  1   8.0   4.4
 21000 -10.5  13.1  335   9  5   7.6   4.2 | -10.6  12.9  295   4  2   7.4   4.1
 20000  -8.2  17.2  325  10  5   7.6   4.2 |  -8.3  17.1  305   7  3   7.4   4.1
 19500  -7.1  19.2  320  11  6   7.8   4.3 |  -7.2  19.0  305   8  4   7.4   4.1
 19000  -6.1  21.0  320  12  6   5.5   3.0 |  -6.3  20.7  305   9  4   5.5   3.0
 18500  -5.3  22.5  320  12  6   5.7   3.1 |  -5.4  22.3  305   9  5   5.7   3.1
 18000  -4.4  24.1  320  12  6   5.4   2.9 |  -4.6  23.7  305   9  5   6.0   3.3
 17500  -3.7  25.3  315  13  7   5.0   2.8 |  -3.7  25.3  305  10  5   6.1   3.4
 17000  -3.0  26.6  310  14  7   5.1   2.8 |  -2.8  27.0  305  10  5   6.2   3.4
 16500  -2.3  27.9  305  14  7   5.1   2.8 |  -1.9  28.6  300  11  6   6.1   3.3
 16000  -1.6  29.1  295  14  7   5.4   2.9 |  -1.1  30.0  295  12  6   6.3   3.5
 15500  -0.9  30.4  290  14  7   5.7   3.1 |  -0.3  31.5  290  13  7   6.2   3.4
 15000  -0.2  31.6  290  12  6   5.9   3.2 |   0.5  32.9  285  13  7   6.5   3.5
 14500   1.0  33.8  280  10  5   6.9   3.8 |   1.8  35.2  280  12  6   7.0   3.9
 14000   2.0  35.6  275   8  4   6.9   3.8 |   2.8  37.0  270  10  5   7.1   3.9
 13500   3.0  37.4  275   7  4   7.6   4.2 |   3.8  38.8  265   8  4   7.0   3.9
 13000   4.1  39.4  280   5  3   7.8   4.3 |   4.8  40.6  255   7  4   7.0   3.9
 12500   5.2  41.4  295   4  2   8.1   4.5 |   5.8  42.4  245   6  3   7.4   4.1
 12000   6.5  43.7  320   4  2   8.3   4.5 |   6.9  44.4  245   5  2   7.6   4.1
 11500   7.7  45.9  340   4  2   7.5   4.1 |   8.0  46.4  245   3  2   6.8   3.8
 11000   8.7  47.7  350   5  3   6.5   3.6 |   9.0  48.2  255   2  1   6.3   3.4
 10500   9.7  49.5  355   6  3   3.7   2.0 |   9.9  49.8  285   1  1   3.4   1.9
 10250   9.8  49.6  360   6  3   2.7   1.5 |  10.0  50.0  295   1  1   1.5   0.8
 10000  10.2  50.4  360   6  3   7.0   3.8 |  10.1  50.2  335   2  1   3.2   1.7
  9750  10.7  51.3  360   7  4   7.6   4.2 |  10.3  50.5  360   3  1   3.1   1.7
  9500  11.1  52.0  360   7  4   5.0   2.8 |  10.5  50.9  010   4  2   3.6   2.0
  9250  11.3  52.3  005   8  4   2.3   1.3 |  10.6  51.1  025   4  2   3.9   2.1
  9000  11.6  52.9  005   9  5   5.0   2.8 |  10.8  51.4  035   5  2   4.0   2.2
  8750  11.9  53.4  015  11  5   6.6   3.6 |  11.0  51.8  045   5  3   4.2   2.3
  8500  12.3  54.1  020  11  6   4.4   2.4 |  11.2  52.2  050   5  3   4.0   2.2
  8250  12.4  54.3  030  12  6   3.5   1.9 |  11.4  52.5  050   5  2   3.3   1.8
  8000  12.6  54.7  040  12  6   3.5   1.9 |  11.7  53.1  045   4  2   5.4   3.0
  7750  12.7  54.9  045  13  7   2.6   1.4 |  12.3  54.1  040   4  2   8.9   4.9
  7500  12.9  55.2  045  14  7   2.2   1.2 |  13.0  55.4  035   4  2   9.4   5.2
  7250  13.1  55.6  045  14  7   1.9   1.0 |  13.7  56.7  035   3  2   9.2   5.0
  7000  13.3  55.9  045  15  8   2.9   1.6 |  14.5  58.1  030   3  2   9.7   5.3
  6750  13.7  56.7  040  15  8   4.5   2.5 |  15.2  59.4  025   3  2  10.4   5.7
  6500  14.1  57.4  030  13  7   4.9   2.7 |  16.0  60.8  025   3  2  10.3   5.7
  6250  14.5  58.1  020  12  6   4.1   2.3 |  16.8  62.2  020   3  2  10.4   5.7
  6000  14.9  58.8  005  11  5   7.1   3.9 |  17.5  63.5  020   3  2  10.1   5.5
  5750  15.7  60.3  355  10  5  12.8   7.0 |  18.4  65.1  015   3  2  14.2   7.8
  5500  16.7  62.1  350   9  5  13.4   7.3 |  19.7  67.5  015   3  2  21.7  11.9

           09/20/2014 at 1500 MDT          |       09/20/2014 at 1800 MDT
                                           |
K index... +20.0  LI... -1.5               | K index... +27.0  LI... -2.2
CAPE... +449.7  CIN... -76.7               | CAPE... +535.8  CIN... -42.0
                                           |
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 -67.7 -89.9  280  51 26   2.3   1.3 | -67.3 -89.1  285  50 26   2.3   1.3
 45000 -61.8 -79.2  280  67 34   6.9   3.8 | -61.6 -78.9  285  66 34   6.6   3.6
 40000 -51.5 -60.7  285  70 36   7.1   3.9 | -51.7 -61.1  285  71 36   6.8   3.7
 38000 -47.2 -53.0  285  65 34   7.1   3.9 | -47.7 -53.9  285  67 35   6.8   3.7
 36000 -43.0 -45.4  290  61 31   7.1   3.9 | -43.6 -46.5  285  64 33   6.7   3.7
 34000 -39.0 -38.2  290  48 25   6.6   3.6 | -39.2 -38.6  285  53 28   7.4   4.1
 32000 -35.1 -31.2  290  34 18   6.6   3.6 | -34.2 -29.6  285  41 21   7.6   4.2
 30000 -30.9 -23.6  290  20 10   6.2   3.4 | -30.3 -22.5  285  31 16   6.5   3.6
 29000 -29.0 -20.2  290  14  7   6.1   3.4 | -28.3 -18.9  285  27 14   6.5   3.6
 28000 -27.1 -16.8  290   8  4   7.7   4.2 | -26.4 -15.5  285  22 11   7.4   4.0
 27000 -24.8 -12.6  280   7  3   7.7   4.2 | -24.1 -11.4  285  19 10   7.4   4.1
 26000 -22.5  -8.5  265   5  3   7.7   4.2 | -21.9  -7.4  280  15  8   7.4   4.1
 25000 -20.2  -4.4  240   5  2   7.9   4.4 | -19.7  -3.5  280  12  6   7.4   4.1
 24000 -17.7   0.1  250   6  3   8.3   4.5 | -17.4   0.7  285  12  6   7.5   4.1
 23000 -15.2   4.6  255   7  4   8.3   4.5 | -15.2   4.6  285  12  6   7.5   4.1
 22000 -12.7   9.1  260   8  4   7.6   4.2 | -12.9   8.8  290  12  6   7.3   4.0
 21000 -10.6  12.9  270   9  5   6.9   3.8 | -10.8  12.6  295  12  6   7.0   3.9
 20000  -8.6  16.5  285  10  5   7.0   3.8 |  -8.7  16.3  300  13  7   7.0   3.9
 19500  -7.5  18.5  290  11  5   7.0   3.8 |  -7.6  18.3  300  13  7   7.1   3.9
 19000  -6.6  20.1  290  11  6   5.9   3.3 |  -6.6  20.1  305  13  7   6.6   3.6
 18500  -5.7  21.7  295  11  6   6.0   3.3 |  -5.6  21.9  310  13  7   6.6   3.6
 18000  -4.8  23.4  295  11  6   6.0   3.3 |  -4.7  23.5  310  13  7   6.5   3.6
 17500  -3.9  25.0  300  12  6   6.1   3.3 |  -3.7  25.3  315  13  7   6.5   3.6
 17000  -3.0  26.6  300  12  6   6.1   3.4 |  -2.8  27.0  315  14  7   6.6   3.6
 16500  -2.0  28.4  300  13  7   7.7   4.2 |  -1.9  28.6  315  14  7   6.3   3.5
 16000  -0.9  30.4  300  14  7   7.8   4.3 |  -1.1  30.0  315  14  7   6.8   3.7
 15500   0.1  32.2  300  14  7   7.1   3.9 |   0.1  32.2  310  13  7   6.2   3.4
 15000   1.4  34.5  295  14  7   7.4   4.1 |   0.9  33.6  300  11  6   6.3   3.5
 14500   2.4  36.3  290  13  6   7.9   4.3 |   1.8  35.2  290  10  5   8.7   4.8
 14000   3.5  38.3  280  11  6   7.9   4.4 |   3.1  37.6  275   8  4   8.7   4.8
 13500   4.5  40.1  270   9  5   7.7   4.2 |   4.4  39.9  255   7  4   8.2   4.5
 13000   5.7  42.3  260   9  5   7.6   4.2 |   5.6  42.1  245   8  4   8.1   4.4
 12500   6.8  44.2  250   9  5   7.5   4.1 |   6.8  44.2  240   9  5   7.6   4.2
 12000   7.9  46.2  240   8  4   7.5   4.1 |   7.9  46.2  230   8  4   7.2   4.0
 11500   9.1  48.4  230   8  4   7.2   4.0 |   8.9  48.0  220   8  4   6.8   3.7
 11000  10.1  50.2  225   7  4   6.8   3.7 |   9.9  49.8  210   7  3   6.2   3.4
 10500  11.1  52.0  215   6  3   2.8   1.5 |  10.9  51.6  190   6  3   2.9   1.6
 10250  11.2  52.2  215   6  3   4.1   2.2 |  11.0  51.8  190   6  3   3.1   1.7
 10000  11.9  53.4  210   5  3  10.0   5.5 |  11.3  52.3  160   4  2   7.8   4.3
  9750  12.5  54.5  200   4  2   9.3   5.1 |  11.7  53.1  125   4  2   6.8   3.7
  9500  13.2  55.8  185   3  2   4.8   2.6 |  12.1  53.8  105   5  3   6.9   3.8
  9250  13.2  55.8  165   3  1   0.9   0.5 |  12.6  54.7  100   5  3   7.0   3.8
  9000  13.3  55.9  130   3  1   3.9   2.2 |  13.2  55.8  100   5  3   9.1   5.0
  8750  13.5  56.3  105   3  2   5.3   2.9 |  13.8  56.8  100   5  3  10.1   5.6
  8500  13.8  56.8  090   4  2   6.4   3.5 |  14.5  58.1  095   5  3   9.3   5.1
  8250  14.3  57.7  085   3  2   6.8   3.7 |  15.2  59.4  095   5  3   8.8   4.8
  8000  14.7  58.5  080   3  2   7.9   4.3 |  15.9  60.6  095   5  3   9.8   5.4
  7750  15.3  59.5  080   3  2   9.7   5.3 |  16.6  61.9  095   5  3  10.6   5.8
  7500  16.0  60.8  080   3  2   9.8   5.4 |  17.4  63.3  095   5  2  10.1   5.5
  7250  16.8  62.2  080   3  2   9.8   5.4 |  18.2  64.8  090   5  2  10.3   5.7
  7000  17.5  63.5  080   3  2  10.2   5.6 |  18.9  66.0  090   5  2   9.2   5.1
  6750  18.3  64.9  075   3  1  10.6   5.8 |  19.6  67.3  090   5  2   9.1   5.0
  6500  19.1  66.4  075   3  1  10.3   5.7 |  20.3  68.5  090   5  2  10.3   5.7
  6250  19.8  67.6  075   2  1  10.4   5.7 |  21.1  70.0  090   4  2  10.1   5.6
  6000  20.6  69.1  075   2  1  10.5   5.8 |  21.8  71.2  090   4  2  10.5   5.7
  5750  21.5  70.7  070   2  1  15.7   8.6 |  22.6  72.7  085   4  2  11.2   6.2
  5500  23.0  73.4  070   2  1  23.4  12.8 |  23.4  74.1  085   4  2  11.6   6.4
________________________________________________________________________________

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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