Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 180121
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1921 MDT Wednesday, September 17, 2014

This forecast is for Thursday, September 18, 2014:

If the trigger temperature of 82.6 F/28.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1118 ft/min (5.7 m/s)
   Maximum height of thermals.................. 17275 ft MSL (11988 ft AGL)

Forecast maximum temperature................... 90.0 F/32.7 C
Time of trigger temperature.................... 1115 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................. 11803 ft MSL (6516 ft AGL)
Thermal soaring outlook for Friday 09/19....... Good

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....................... 19812 ft MSL (14525 ft AGL)
Wave soaring outlook for Friday 09/19.......... Poor

Remarks...

Sunrise/Sunset.................... 06:43:21 / 19:04:38 MDT
Total possible sunshine........... 12 hr 21 min 17 sec (741 min 17 sec)
Altitude of sun at 12:53:30 MDT... 51.92 degrees

Upper air data from numerical model forecast valid on 09/18/2014 at 0600 MDT

Freezing level.................. 15631 ft MSL (10344 ft AGL)
Convective condensation level... 17295 ft MSL (12008 ft AGL)
Lifted condensation level....... 17388 ft MSL (12101 ft AGL)
Lifted index.................... -1.7
K index......................... +11.2

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   295   45   23   2.5   1.4      M     M       M      M    M
 45000  -62.3 -80.1   295   56   29   5.3   2.9      M     M       M      M    M
 40000  -54.0 -65.2   295   56   29   7.6   4.2      M     M       M      M    M
 38000  -49.4 -56.9   305   50   26   7.6   4.2      M     M       M      M    M
 36000  -44.9 -48.8   320   47   24   7.6   4.2      M     M       M      M    M
 34000  -40.3 -40.5   320   41   21   7.7   4.2      M     M       M      M    M
 32000  -35.6 -32.1   320   35   18   7.7   4.2      M     M       M      M    M
 30000  -30.8 -23.4   320   28   14   7.1   3.9   44.8 112.6     9.6      M    M
 29000  -28.6 -19.5   320   25   13   7.1   3.9   43.8 110.9     8.9      M    M
 28000  -26.5 -15.7   320   21   11   7.0   3.8   42.9 109.3     8.3      M    M
 27000  -24.4 -11.9   320   19   10   7.0   3.8   41.7 107.1     7.5      M    M
 26000  -22.4  -8.3   320   17    9   7.0   3.8   40.7 105.2     6.7      M    M
 25000  -20.3  -4.5   325   15    8   7.0   3.8   39.7 103.5     6.0      M    M
 24000  -18.2  -0.8   330   13    7   7.0   3.8   38.7 101.6     5.2      M    M
 23000  -16.1   3.0   335   12    6   7.0   3.8   37.6  99.7     4.4      M    M
 22000  -14.0   6.8   345   11    6   7.0   3.9   36.7  98.1     3.7      M    M
 21000  -11.8  10.8   355   11    6   7.3   4.0   35.8  96.4     2.9      M    M
 20000   -9.6  14.7   010   12    6   7.3   4.0   34.9  94.8     2.2      M    M
 19500   -8.5  16.7   015   13    6   7.3   4.0   34.5  94.1     1.9      M    M
 19000   -7.5  18.5   020   13    7   6.9   3.8   34.1  93.4     1.6      M    M
 18500   -6.4  20.5   020   12    6   6.9   3.8   33.6  92.5     1.1      M    M
 18000   -5.4  22.3   025   11    6   7.0   3.9   33.1  91.6     0.7      M    M
 17500   -4.4  24.1   025   10    5   7.3   4.0   32.7  90.8     0.3      M    M
 17000   -3.3  26.1   025    9    5   7.3   4.0   32.3  90.1    -0.1   1101  5.6
 16500   -2.2  28.0   025    8    4   7.5   4.1   31.9  89.4    -0.5   1054  5.4
 16000   -1.1  30.0   020    8    4   7.6   4.2   31.5  88.7    -0.9   1006  5.1
 15500    0.6  33.1   015    8    4   8.3   4.6   31.0  87.8    -1.4    933  4.7
 15000    1.8  35.2   015    8    4   8.3   4.6   30.7  87.3    -1.7    883  4.5
 14500    3.0  37.4   010    7    4   8.7   4.8   30.5  87.0    -2.0    832  4.2
 14000    4.2  39.6   010    6    3   8.9   4.9   30.4  86.7    -2.2    780  4.0
 13500    5.5  41.9   015    5    3   8.8   4.9   30.3  86.5    -2.4    727  3.7
 13000    6.7  44.1   010    4    2   8.7   4.8   30.1  86.1    -2.6    674  3.4
 12500    8.0  46.4   005    3    1   8.8   4.8   29.9  85.8    -2.8    621  3.2
 12000    9.3  48.7   345    2    1   9.1   5.0   29.8  85.6    -3.0    567  2.9
 11500   10.7  51.3   295    1    1   9.0   4.9   29.7  85.4    -3.1    512  2.6
 11000   12.0  53.6   250    2    1   8.3   4.5   29.5  85.1    -3.3    459  2.3
 10500   13.2  55.8   240    4    2   5.7   3.1   29.3  84.8    -3.5    405  2.1
 10250   13.6  56.5   240    4    2   6.7   3.7   28.9  84.0    -3.9    389  2.0
 10000   14.3  57.7   235    6    3  11.0   6.0   28.9  84.1    -3.9    359  1.8
  9750   15.1  59.2   235    7    3  10.0   5.5   29.0  84.1    -3.9    329  1.7
  9500   15.8  60.4   230    8    4   9.8   5.4   29.0  84.2    -3.9    299  1.5
  9250   16.5  61.7   230    9    5   8.7   4.8   28.9  84.1    -3.9    272  1.4
  9000   17.1  62.8   230    9    5   9.0   4.9   28.9  84.0    -4.1    246  1.2
  8750   17.8  64.0   230   10    5   9.5   5.2   28.8  83.9    -4.1    218  1.1
  8500   18.4  65.1   225   10    5   9.0   4.9   28.8  83.8    -4.2    191  1.0
  8250   19.0  66.2   225   10    5   8.4   4.6   28.7  83.7    -4.3    165  0.8
  8000   19.6  67.3   225   10    5   8.2   4.5   28.6  83.5    -4.5    140  0.7
  7750   20.2  68.4   225   10    5   8.2   4.5   28.5  83.3    -4.6    114  0.6
  7500   20.8  69.4   225   11    5   7.9   4.3   28.4  83.0    -4.7     89  0.5
  7250   21.4  70.5   225   11    5   7.5   4.1   28.2  82.7    -4.9     65  0.3
  7000   21.9  71.4   220   11    5   7.4   4.1   28.0  82.4    -5.1     41  0.2
  6750   22.4  72.3   220   11    5   6.8   3.7   27.8  82.1    -5.4     19  0.1
  6500   22.7  72.9   220   10    5  -3.1  -1.7   27.3  81.2    -5.9      5  0.0
  6250   21.9  71.4   220    9    5 -12.0  -6.6   25.9  78.6    -7.4     19  0.1
  6000   21.2  70.2   220    9    4  -4.0  -2.2   24.5  76.1    -8.9     34  0.2
  5750   20.8  69.4   225    8    4 -15.6  -8.6   23.3  74.0   -10.0     39  0.2
  5500   17.9  64.2   220    6    3 -59.8 -32.8   19.9  67.8   -13.6    119  0.6

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

           09/18/2014 at 0900 MDT          |       09/18/2014 at 1200 MDT
                                           |
K index... +6.0  LI... +1.6                | K index... +5.2  LI... -0.6
CAPE... 0.0  CIN... M                      | CAPE... +21.3  CIN... -33.7
                                           |
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 -67.8 -90.0  290  43 22   2.3   1.3 | -67.2 -89.0  290  40 20   1.3   0.7
 45000 -62.8 -81.0  290  53 27   5.5   3.0 | -63.3 -81.9  290  49 25   5.4   3.0
 40000 -54.2 -65.6  300  47 24   7.6   4.2 | -54.8 -66.6  285  41 21   7.8   4.3
 38000 -49.6 -57.3  305  43 22   7.7   4.2 | -50.1 -58.2  295  35 18   7.9   4.3
 36000 -45.0 -49.0  320  40 21   7.7   4.2 | -45.3 -49.5  305  30 16   7.9   4.3
 34000 -40.3 -40.5  325  36 19   7.9   4.3 | -40.4 -40.7  310  26 14   8.2   4.5
 32000 -35.6 -32.1  330  32 17   7.9   4.3 | -34.9 -30.8  315  22 11   8.5   4.6
 30000 -30.5 -22.9  330  27 14   7.6   4.1 | -30.0 -22.0  315  19 10   8.2   4.5
 29000 -28.2 -18.8  330  24 12   7.6   4.1 | -27.5 -17.5  320  17  9   8.2   4.5
 28000 -26.0 -14.8  325  21 11   6.9   3.8 | -25.1 -13.2  320  16  8   7.1   3.9
 27000 -24.0 -11.2  325  18  9   6.7   3.7 | -23.1  -9.6  320  14  7   6.7   3.7
 26000 -22.0  -7.6  325  16  8   6.7   3.7 | -21.1  -6.0  315  12  6   6.7   3.7
 25000 -20.0  -4.0  320  13  7   6.7   3.7 | -19.1  -2.4  310  10  5   6.7   3.7
 24000 -18.0  -0.4  325  11  6   6.6   3.6 | -17.1   1.2  300   8  4   6.6   3.6
 23000 -16.1   3.0  330   9  4   6.6   3.6 | -15.1   4.8  290   7  3   6.6   3.6
 22000 -14.1   6.6  335   7  3   6.6   3.6 | -13.2   8.2  275   5  3   6.5   3.6
 21000 -12.1  10.2  010   6  3   6.9   3.8 | -11.4  11.5  275   3  1   6.2   3.4
 20000 -10.1  13.8  035   9  4   6.9   3.8 |  -9.6  14.7  000   0  0   6.2   3.4
 19500  -9.1  15.6  040  10  5   6.9   3.8 |  -8.7  16.3  080   2  1   6.1   3.4
 19000  -8.0  17.6  045  11  6   8.0   4.4 |  -7.7  18.1  090   3  1   7.8   4.3
 18500  -6.7  19.9  050  10  5   8.1   4.4 |  -6.5  20.3  100   3  2   7.9   4.3
 18000  -5.5  22.1  050   9  5   8.1   4.4 |  -5.3  22.5  110   4  2   7.9   4.3
 17500  -4.3  24.3  055   8  4   7.9   4.3 |  -4.1  24.6  115   4  2   7.8   4.3
 17000  -3.1  26.4  055   6  3   7.9   4.3 |  -2.9  26.8  120   3  2   7.8   4.3
 16500  -1.9  28.6  060   5  3   7.8   4.3 |  -1.7  28.9  125   3  2   7.9   4.3
 16000  -0.7  30.7  065   4  2   7.8   4.3 |   0.1  32.2  140   3  2   8.0   4.4
 15500   1.0  33.8  080   3  2   7.6   4.2 |   1.2  34.2  155   3  2   7.4   4.0
 15000   2.1  35.8  090   3  2   7.6   4.2 |   2.3  36.1  170   4  2   7.4   4.1
 14500   3.3  37.9  100   3  2   8.0   4.4 |   3.4  38.1  180   5  2   8.1   4.4
 14000   4.4  39.9  105   3  1   8.2   4.5 |   4.6  40.3  180   5  3   8.3   4.6
 13500   5.6  42.1  110   3  1   8.6   4.7 |   5.8  42.4  185   6  3   8.7   4.8
 13000   6.9  44.4  115   3  1   9.0   4.9 |   7.1  44.8  180   6  3   9.0   4.9
 12500   8.2  46.8  125   3  1   9.1   5.0 |   8.4  47.1  180   6  3   9.0   4.9
 12000   9.5  49.1  130   3  1   9.1   5.0 |   9.7  49.5  180   6  3   8.9   4.9
 11500  10.8  51.4  135   3  1   9.2   5.0 |  11.0  51.8  180   5  3   8.9   4.9
 11000  12.2  54.0  155   3  1   9.1   5.0 |  12.3  54.1  180   6  3   8.7   4.8
 10500  13.5  56.3  170   3  2   5.6   3.1 |  13.7  56.7  185   6  3   5.5   3.0
 10250  13.8  56.8  175   4  2   6.0   3.3 |  13.9  57.0  185   6  3   6.2   3.4
 10000  14.5  58.1  185   4  2  10.9   6.0 |  14.7  58.5  190   6  3  11.0   6.0
  9750  15.3  59.5  190   5  3   9.8   5.4 |  15.4  59.7  190   7  4   9.9   5.4
  9500  16.0  60.8  195   6  3   9.3   5.1 |  16.1  61.0  195   7  4   9.4   5.2
  9250  16.6  61.9  200   7  3   8.2   4.5 |  16.8  62.2  195   8  4   8.3   4.6
  9000  17.3  63.1  205   7  4   9.2   5.1 |  17.4  63.3  195   8  4   9.0   5.0
  8750  18.0  64.4  205   8  4   9.9   5.4 |  18.1  64.6  200   8  4   9.5   5.2
  8500  18.7  65.7  210   9  5   9.5   5.2 |  18.8  65.8  200   9  4   9.2   5.1
  8250  19.4  66.9  210  10  5   9.6   5.3 |  19.4  66.9  200   9  5   9.3   5.1
  8000  20.1  68.2  215  11  5   8.2   4.5 |  20.1  68.2  205   9  5   8.4   4.6
  7750  20.6  69.1  215  11  6   6.7   3.7 |  20.6  69.1  205   9  5   7.4   4.0
  7500  21.1  70.0  215  11  6   7.4   4.1 |  21.1  70.0  205   9  5   8.6   4.7
  7250  21.7  71.1  215  11  6   7.8   4.3 |  21.8  71.2  200   8  4   9.7   5.3
  7000  22.2  72.0  220  11  6   8.0   4.4 |  22.4  72.3  200   7  4   9.5   5.2
  6750  22.8  73.0  220  11  6   7.1   3.9 |  23.1  73.6  200   7  3   9.7   5.3
  6500  23.1  73.6  220  11  6  -1.7  -0.9 |  23.8  74.8  200   6  3  10.6   5.8
  6250  22.6  72.7  225  10  5  -7.6  -4.2 |  24.7  76.5  200   6  3  11.5   6.3
  6000  22.0  71.6  225   9  5  -4.6  -2.5 |  25.5  77.9  200   5  3  10.2   5.6
  5750  21.6  70.9  230   8  4  -8.0  -4.4 |  26.2  79.2  200   5  3  11.8   6.5
  5500  20.5  68.9  225   7  4 -17.6  -9.7 |  27.4  81.3  200   5  2  19.6  10.7

           09/18/2014 at 1500 MDT          |       09/18/2014 at 1800 MDT
                                           |
K index... +9.9  LI... +0.9                | K index... +1.9  LI... +2.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.7
                                           |
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 -67.8 -90.0  285  40 21   2.0   1.1 | -67.7 -89.9  280  41 21   2.3   1.3
 45000 -63.1 -81.6  285  46 24   5.5   3.0 | -62.8 -81.0  280  47 24   5.6   3.1
 40000 -54.6 -66.3  280  39 20   7.5   4.1 | -54.1 -65.4  275  41 21   7.3   4.0
 38000 -50.0 -58.0  285  34 17   7.6   4.2 | -49.7 -57.5  275  37 19   7.4   4.1
 36000 -45.4 -49.7  285  29 15   7.6   4.1 | -45.2 -49.4  270  33 17   7.3   4.0
 34000 -40.4 -40.7  290  24 12   8.5   4.6 | -40.3 -40.5  275  26 13   8.4   4.6
 32000 -34.7 -30.5  300  19 10   8.7   4.8 | -34.6 -30.3  285  17  9   8.5   4.7
 30000 -29.6 -21.3  300  16  8   8.6   4.7 | -29.4 -20.9  285  14  7   8.8   4.8
 29000 -27.0 -16.6  300  14  7   8.6   4.7 | -26.8 -16.2  290  12  6   8.8   4.8
 28000 -24.5 -12.1  300  12  6   7.2   3.9 | -24.2 -11.6  290  11  6   7.2   4.0
 27000 -22.4  -8.3  295  11  6   6.8   3.7 | -22.2  -8.0  280  10  5   6.7   3.7
 26000 -20.4  -4.7  285  10  5   6.8   3.7 | -20.2  -4.4  270  10  5   6.7   3.7
 25000 -18.4  -1.1  275   9  5   6.8   3.8 | -18.1  -0.6  260   9  5   6.8   3.7
 24000 -16.3   2.7  270   9  4   6.8   3.8 | -16.1   3.0  255   9  5   7.0   3.8
 23000 -14.3   6.3  265   9  5   6.8   3.8 | -14.0   6.8  255   9  5   7.0   3.8
 22000 -12.2  10.0  260   9  5   6.7   3.7 | -11.9  10.6  250   9  5   6.9   3.8
 21000 -10.4  13.3  250   7  4   5.9   3.3 |  -9.9  14.2  250   8  4   6.4   3.5
 20000  -8.7  16.3  230   6  3   6.0   3.3 |  -8.0  17.6  250   8  4   6.4   3.5
 19500  -7.8  18.0  220   5  3   5.9   3.2 |  -7.0  19.4  245   8  4   6.4   3.5
 19000  -6.8  19.8  210   5  3   7.5   4.1 |  -6.1  21.0  245   7  4   6.7   3.7
 18500  -5.7  21.7  205   5  2   7.6   4.2 |  -5.1  22.8  250   7  3   6.8   3.7
 18000  -4.5  23.9  200   4  2   7.5   4.1 |  -4.1  24.6  255   6  3   6.9   3.8
 17500  -3.5  25.7  195   4  2   6.9   3.8 |  -3.0  26.6  255   5  3   7.7   4.2
 17000  -2.4  27.7  190   4  2   6.9   3.8 |  -1.8  28.8  255   5  3   7.6   4.2
 16500  -1.3  29.7  185   4  2   7.4   4.1 |  -0.7  30.7  250   4  2   7.7   4.2
 16000   0.3  32.5  180   5  3   7.5   4.1 |   1.0  33.8  230   4  2   7.7   4.2
 15500   1.4  34.5  180   6  3   7.3   4.0 |   2.2  36.0  220   4  2   7.7   4.2
 15000   2.5  36.5  185   7  4   7.4   4.0 |   3.3  37.9  220   5  3   7.7   4.2
 14500   3.5  38.3  185   9  4   8.2   4.5 |   4.5  40.1  215   6  3   7.9   4.4
 14000   4.8  40.6  185   9  5   8.5   4.7 |   5.6  42.1  215   7  3   8.1   4.4
 13500   6.0  42.8  185  10  5   8.7   4.8 |   6.8  44.2  210   8  4   8.1   4.4
 13000   7.2  45.0  185  10  5   8.8   4.8 |   7.9  46.2  205   8  4   8.0   4.4
 12500   8.5  47.3  185  10  5   8.9   4.9 |   9.0  48.2  200   9  5   8.3   4.5
 12000   9.8  49.6  185  10  5   9.0   5.0 |  10.3  50.5  195  10  5   8.9   4.9
 11500  11.1  52.0  185  10  5   8.9   4.9 |  11.6  52.9  190  10  5   8.8   4.8
 11000  12.3  54.1  185  10  5   8.4   4.6 |  12.8  55.0  185  11  6   8.1   4.4
 10500  13.5  56.3  185   9  5  12.4   6.8 |  14.0  57.2  180  12  6  10.8   5.9
 10250  14.6  58.3  185   9  5  13.1   7.2 |  14.9  58.8  175  12  6  11.7   6.4
 10000  15.2  59.4  185   9  4   8.1   4.5 |  15.6  60.1  175  13  7   8.7   4.8
  9750  15.9  60.6  185   9  4   9.7   5.3 |  16.3  61.3  175  14  7   9.6   5.3
  9500  16.6  61.9  185   9  4   8.5   4.6 |  17.0  62.6  175  14  7   9.0   4.9
  9250  17.2  63.0  185   8  4   8.4   4.6 |  17.6  63.7  175  15  8   8.5   4.7
  9000  17.9  64.2  185   8  4  10.0   5.5 |  18.3  64.9  175  15  8   9.2   5.0
  8750  18.7  65.7  185   8  4  10.5   5.8 |  19.0  66.2  175  16  8   9.6   5.3
  8500  19.4  66.9  185   8  4  10.5   5.8 |  19.7  67.5  175  16  8   9.6   5.3
  8250  20.2  68.4  190   8  4  11.0   6.1 |  20.4  68.7  175  17  8  10.0   5.5
  8000  21.0  69.8  190   8  4  10.2   5.6 |  21.2  70.2  175  17  9   9.8   5.4
  7750  21.7  71.1  190   8  4   9.2   5.0 |  21.9  71.4  175  16  8   9.5   5.2
  7500  22.5  72.5  190   8  4   9.8   5.4 |  22.6  72.7  175  16  8   9.6   5.3
  7250  23.2  73.8  190   8  4  10.4   5.7 |  23.3  73.9  175  16  8   9.7   5.3
  7000  24.0  75.2  190   8  4  10.1   5.6 |  24.0  75.2  175  16  8   9.6   5.3
  6750  24.7  76.5  190   8  4   9.4   5.2 |  24.7  76.5  175  16  8   9.2   5.0
  6500  25.4  77.7  195   8  4  10.0   5.5 |  25.4  77.7  175  16  8   9.6   5.3
  6250  26.2  79.2  195   7  4  10.9   6.0 |  26.1  79.0  175  15  8  10.1   5.6
  6000  27.0  80.6  195   7  4  10.0   5.5 |  26.9  80.4  175  14  7   9.9   5.4
  5750  27.8  82.0  195   7  4  12.1   6.6 |  27.6  81.7  175  13  7   8.5   4.6
  5500  28.9  84.0  195   7  4  19.1  10.5 |  28.1  82.6  175  11  6   6.3   3.5
________________________________________________________________________________

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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