Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 220119
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1919 MDT Sunday, September 21, 2014

This forecast is for Monday, September 22, 2014:

If the trigger temperature of 76.6 F/24.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 385 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10367 ft MSL (5080 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1345 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Broken/overcast thin middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7620 ft MSL (2333 ft AGL)
Thermal soaring outlook for Tuesday 09/23...... Excellent

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 17097 ft MSL (11810 ft AGL)
Wave soaring outlook for Tuesday 09/23......... Good

Remarks...

Sunrise/Sunset.................... 06:47:07 / 18:58:04 MDT
Total possible sunshine........... 12 hr 10 min 56 sec (730 min 56 sec)
Altitude of sun at 12:52:05 MDT... 50.36 degrees

Upper air data from numerical model forecast valid on 09/22/2014 at 0600 MDT

Freezing level.................. 14695 ft MSL (9408 ft AGL)
Convective condensation level... 13209 ft MSL (7922 ft AGL)
Lifted condensation level....... 12499 ft MSL (7212 ft AGL)
Lifted index.................... -1.1
K index......................... +30.3

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  -64.9 -84.8   295   34   17   3.6   2.0      M     M       M      M    M
 45000  -58.9 -74.0   290   51   26   4.3   2.3      M     M       M      M    M
 40000  -52.3 -62.1   270   66   34   5.3   2.9      M     M       M      M    M
 38000  -49.1 -56.4   265   56   29   5.3   2.9      M     M       M      M    M
 36000  -45.9 -50.6   255   47   24   5.0   2.7      M     M       M      M    M
 34000  -40.9 -41.6   250   38   20   9.0   4.9      M     M       M      M    M
 32000  -35.5 -31.9   245   30   16   8.8   4.8      M     M       M      M    M
 30000  -30.1 -22.2   245   25   13   7.8   4.3   46.0 114.8    15.5      M    M
 29000  -27.8 -18.0   245   23   12   7.8   4.3   45.3 113.5    15.1      M    M
 28000  -25.5 -13.9   245   21   11   7.2   4.0   44.6 112.3    14.7      M    M
 27000  -23.4 -10.1   245   20   10   7.1   3.9   43.5 110.2    14.0      M    M
 26000  -21.3  -6.3   250   19   10   7.1   3.9   42.5 108.4    13.3      M    M
 25000  -19.2  -2.6   250   19   10   7.0   3.8   41.6 106.9    12.7      M    M
 24000  -17.4   0.7   255   17    9   6.1   3.3   40.2 104.4    11.7      M    M
 23000  -15.6   3.9   255   16    8   6.1   3.4   38.9 102.0    10.7      M    M
 22000  -13.8   7.2   255   15    8   6.0   3.3   37.7  99.8     9.8      M    M
 21000  -12.1  10.2   245   13    7   5.7   3.1   36.1  97.0     8.5      M    M
 20000  -10.5  13.1   235   12    6   5.7   3.1   34.7  94.5     7.3      M    M
 19500   -9.7  14.5   230   11    6   5.6   3.1   34.0  93.3     6.8      M    M
 19000   -8.8  16.2   220   11    6   7.1   3.9   33.5  92.2     6.2      M    M
 18500   -7.8  18.0   220   11    6   7.1   3.9   33.0  91.4     5.8      M    M
 18000   -6.8  19.8   215   11    6   6.9   3.8   32.5  90.6     5.4      M    M
 17500   -5.8  21.6   215   11    6   6.4   3.5   32.0  89.5     4.9      M    M
 17000   -4.9  23.2   220   11    6   6.4   3.5   31.4  88.5     4.4      M    M
 16500   -4.0  24.8   220   11    6   6.9   3.8   30.9  87.6     3.9      M    M
 16000   -3.0  26.6   225   10    5   6.9   3.8   30.4  86.7     3.5      M    M
 15500   -2.0  28.4   225    9    5   7.1   3.9   29.9  85.8     3.0      M    M
 15000   -0.4  31.3   235    8    4   7.2   4.0   29.3  84.7     2.4      M    M
 14500    0.7  33.3   240    8    4   8.5   4.7   29.0  84.1     2.1      M    M
 14000    2.0  35.6   250    8    4   8.7   4.8   28.8  83.8     1.9      M    M
 13500    3.3  37.9   255    8    4   8.6   4.7   28.6  83.5     1.8      M    M
 13000    4.5  40.1   260    9    5   8.5   4.6   28.4  83.1     1.6      M    M
 12500    5.8  42.4   265   10    5   8.1   4.5   28.2  82.8     1.4      M    M
 12000    6.9  44.4   260   12    6   7.8   4.3   27.9  82.2     1.1      M    M
 11500    8.0  46.4   260   13    7   7.8   4.3   27.6  81.6     0.8      M    M
 11000    9.2  48.6   260   16    8   7.7   4.2   27.3  81.1     0.5      M    M
 10500   10.4  50.7   255   18    9   4.8   2.6   27.0  80.6     0.2      M    M
 10250   10.6  51.1   255   18    9   4.9   2.7   26.5  79.6    -0.3    376  1.9
 10000   11.2  52.2   255   20   10   9.8   5.4   26.4  79.4    -0.4    350  1.8
  9750   11.9  53.4   250   21   11  10.1   5.6   26.3  79.4    -0.5    321  1.6
  9500   12.6  54.7   250   23   12   7.7   4.2   26.3  79.4    -0.5    293  1.5
  9250   13.0  55.4   250   24   12   4.6   2.5   26.0  78.8    -0.8    274  1.4
  9000   13.4  56.1   250   25   13   6.6   3.6   25.7  78.2    -1.2    255  1.3
  8750   13.9  57.0   250   26   13   8.0   4.4   25.5  77.9    -1.4    232  1.2
  8500   14.4  57.9   250   27   14   6.1   3.4   25.3  77.6    -1.6    209  1.1
  8250   14.8  58.6   245   27   14   4.7   2.6   25.0  76.9    -2.0    191  1.0
  8000   15.1  59.2   245   27   14   5.3   2.9   24.6  76.3    -2.4    174  0.9
  7750   15.5  59.9   240   27   14   5.0   2.7   24.3  75.7    -2.8    156  0.8
  7500   15.7  60.3   235   27   14   3.4   1.9   23.8  74.9    -3.2    140  0.7
  7250   15.9  60.6   230   27   14   2.4   1.3   23.3  73.9    -3.8    127  0.6
  7000   16.1  61.0   225   27   14   3.0   1.7   22.8  73.0    -4.3    114  0.6
  6750   16.2  61.2   220   27   14  -1.8  -1.0   22.1  71.8    -5.0    104  0.5
  6500   15.8  60.4   215   26   13  -6.4  -3.5   21.0  69.8    -6.1    108  0.5
  6250   15.4  59.7   210   24   13  -7.2  -3.9   19.8  67.6    -7.3    115  0.6
  6000   14.9  58.8   200   23   12  -3.1  -1.7   18.6  65.4    -8.5    122  0.6
  5750   14.9  58.8   195   21   11   0.5   0.3   17.8  64.1    -9.2    114  0.6
  5500   14.7  58.5   195   16    8  -5.9  -3.2   17.0  62.6   -10.2    113  0.6

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

           09/22/2014 at 0900 MDT          |       09/22/2014 at 1200 MDT
                                           |
K index... +29.1  LI... 0.0                | K index... +26.4  LI... -1.8
CAPE... 0.0  CIN... -24.7                  | CAPE... +243.4  CIN... -57.6
                                           |
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 -65.6 -86.1  285  33 17   3.6   2.0 | -65.1 -85.2  280  29 15   3.7   2.0
 45000 -58.9 -74.0  280  49 25   5.5   3.0 | -58.5 -73.3  275  41 21   5.2   2.9
 40000 -50.9 -59.6  270  55 28   4.3   2.3 | -50.8 -59.4  270  47 24   4.3   2.3
 38000 -48.3 -54.9  265  43 22   4.2   2.3 | -48.3 -54.9  260  44 23   4.2   2.3
 36000 -45.8 -50.4  260  32 16   4.0   2.2 | -45.8 -50.4  250  42 22   4.0   2.2
 34000 -41.4 -42.5  260  29 15   7.9   4.4 | -41.3 -42.3  240  40 20   8.1   4.4
 32000 -36.7 -34.1  255  28 14   7.8   4.3 | -36.5 -33.7  230  38 20   8.1   4.4
 30000 -31.0 -23.8  255  30 15   8.5   4.6 | -31.2 -24.2  230  37 19   7.9   4.3
 29000 -28.5 -19.3  260  31 16   8.5   4.7 | -28.8 -19.8  230  36 19   7.9   4.4
 28000 -26.0 -14.8  260  32 17   7.9   4.3 | -26.5 -15.7  230  36 18   7.8   4.3
 27000 -23.7 -10.7  255  32 16   7.8   4.3 | -24.2 -11.6  230  35 18   7.8   4.3
 26000 -21.4  -6.5  255  31 16   7.8   4.3 | -21.9  -7.4  230  33 17   7.8   4.3
 25000 -19.1  -2.4  255  31 16   7.7   4.2 | -19.6  -3.3  230  32 17   7.8   4.3
 24000 -17.2   1.0  250  30 15   6.5   3.6 | -17.5   0.5  235  32 16   7.0   3.8
 23000 -15.3   4.5  245  29 15   6.6   3.6 | -15.5   4.1  240  32 17   7.0   3.8
 22000 -13.3   8.1  240  28 14   6.5   3.6 | -13.4   7.9  240  33 17   6.8   3.7
 21000 -11.5  11.3  235  28 14   6.3   3.5 | -11.6  11.1  245  30 15   6.1   3.3
 20000  -9.7  14.5  230  28 14   6.4   3.5 |  -9.8  14.4  245  27 14   6.1   3.3
 19500  -8.8  16.2  230  28 14   6.4   3.5 |  -9.0  15.8  245  25 13   6.1   3.3
 19000  -7.9  17.8  230  28 14   5.8   3.2 |  -8.0  17.6  245  24 12   6.7   3.7
 18500  -7.0  19.4  230  27 14   5.8   3.2 |  -7.1  19.2  245  23 12   6.7   3.7
 18000  -6.2  20.8  230  27 14   5.9   3.2 |  -6.1  21.0  245  23 12   6.4   3.5
 17500  -5.3  22.5  230  27 14   6.2   3.4 |  -5.3  22.5  250  24 12   5.5   3.0
 17000  -4.4  24.1  230  26 13   6.2   3.4 |  -4.4  24.1  255  26 13   5.5   3.0
 16500  -3.6  25.5  230  26 13   6.1   3.3 |  -3.6  25.5  255  27 14   5.7   3.1
 16000  -2.7  27.1  235  26 13   6.1   3.3 |  -2.8  27.0  260  28 15   5.7   3.1
 15500  -1.8  28.8  240  27 14   5.7   3.1 |  -1.9  28.6  260  29 15   6.1   3.3
 15000  -0.7  30.7  240  25 13   5.4   2.9 |  -0.6  30.9  260  26 14   6.4   3.5
 14500   0.1  32.2  240  24 12   5.3   2.9 |   0.3  32.5  265  25 13   6.0   3.3
 14000   0.9  33.6  240  24 12   5.3   2.9 |   1.2  34.2  265  23 12   5.9   3.3
 13500   1.7  35.1  240  23 12   6.5   3.6 |   2.0  35.6  265  22 11   6.9   3.8
 13000   2.7  36.9  240  22 11   7.2   4.0 |   3.1  37.6  265  20 11   7.5   4.1
 12500   3.8  38.8  240  21 11   7.5   4.1 |   4.2  39.6  265  19 10   8.0   4.4
 12000   4.9  40.8  240  20 10   7.8   4.3 |   5.5  41.9  270  18  9   8.5   4.7
 11500   6.0  42.8  240  19 10   7.3   4.0 |   6.7  44.1  270  16  8   7.9   4.3
 11000   7.0  44.6  240  17  9   6.5   3.5 |   7.7  45.9  270  14  7   6.7   3.6
 10500   7.9  46.2  240  16  8   3.9   2.1 |   8.7  47.7  275  12  6   4.3   2.3
 10250   8.1  46.6  245  16  8   2.9   1.6 |   8.9  48.0  275  12  6   4.1   2.2
 10000   8.5  47.3  245  16  8   7.4   4.0 |   9.4  48.9  275  11  6   8.2   4.5
  9750   9.1  48.4  245  15  8   8.5   4.6 |  10.0  50.0  280  10  5   8.8   4.8
  9500   9.6  49.3  245  15  8   6.7   3.7 |  10.6  51.1  285   9  5   6.9   3.8
  9250  10.0  50.0  245  14  7   4.9   2.7 |  10.9  51.6  285   8  4   4.6   2.5
  9000  10.4  50.7  245  14  7   6.5   3.6 |  11.3  52.3  285   8  4   6.6   3.6
  8750  10.9  51.6  245  14  7   7.6   4.2 |  11.8  53.2  285   7  3   8.0   4.4
  8500  11.4  52.5  245  14  7   6.3   3.5 |  12.3  54.1  280   6  3   6.8   3.7
  8250  11.8  53.2  250  14  7   5.4   3.0 |  12.8  55.0  260   5  3   6.2   3.4
  8000  12.2  54.0  250  13  7   6.5   3.5 |  13.2  55.8  240   5  3   6.3   3.4
  7750  12.7  54.9  250  13  7   6.5   3.6 |  13.6  56.5  225   6  3   5.8   3.2
  7500  13.1  55.6  250  13  6   4.5   2.5 |  14.0  57.2  210   8  4   4.9   2.7
  7250  13.4  56.1  255  12  6   3.5   1.9 |  14.3  57.7  200   9  5   5.2   2.8
  7000  13.7  56.7  255  11  5   4.5   2.5 |  14.6  58.3  195  10  5   3.1   1.7
  6750  14.0  57.2  260  10  5   3.1   1.7 |  14.8  58.6  190  12  6   4.7   2.6
  6500  14.1  57.4  260   8  4   1.3   0.7 |  15.3  59.5  185  11  6   9.2   5.1
  6250  14.2  57.6  255   6  3   1.9   1.0 |  16.0  60.8  185  11  6   8.7   4.8
  6000  14.3  57.7  245   5  2   1.1   0.6 |  16.6  61.9  180  11  5  10.4   5.7
  5750  14.3  57.7  235   3  2   2.3   1.3 |  17.5  63.5  180  10  5  13.4   7.4
  5500  14.6  58.3  205   2  1   6.2   3.4 |  18.5  65.3  185   9  5  13.5   7.4

           09/22/2014 at 1500 MDT          |       09/22/2014 at 1800 MDT
                                           |
K index... +28.3  LI... -2.3               | K index... +29.2  LI... -2.9
CAPE... +509.3  CIN... -7.8                | CAPE... +415.8  CIN... -10.1
                                           |
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  280  28 14   3.4   1.8 | -63.9 -83.0  285  26 13   3.5   1.9
 45000 -58.3 -72.9  270  41 21   5.1   2.8 | -57.7 -71.9  275  40 20   5.0   2.7
 40000 -50.6 -59.1  270  49 25   5.1   2.8 | -50.2 -58.4  270  46 24   5.0   2.8
 38000 -47.6 -53.7  265  47 24   5.1   2.8 | -47.2 -53.0  270  45 23   5.0   2.8
 36000 -44.6 -48.3  255  46 24   5.0   2.8 | -44.2 -47.6  270  43 22   5.0   2.8
 34000 -40.6 -41.1  250  46 24   7.0   3.8 | -40.6 -41.1  270  42 22   6.3   3.4
 32000 -36.4 -33.5  245  46 24   7.0   3.9 | -36.9 -34.4  270  42 21   6.3   3.5
 30000 -31.6 -24.9  245  43 22   7.3   4.0 | -32.1 -25.8  270  41 21   7.5   4.1
 29000 -29.4 -20.9  250  41 21   7.3   4.0 | -29.8 -21.6  270  41 21   7.5   4.1
 28000 -27.2 -17.0  250  39 20   7.6   4.2 | -27.6 -17.7  265  41 21   7.7   4.2
 27000 -24.9 -12.8  250  37 19   7.8   4.3 | -25.3 -13.5  265  40 21   7.9   4.3
 26000 -22.6  -8.7  245  36 18   7.8   4.3 | -22.9  -9.2  265  40 20   7.9   4.3
 25000 -20.3  -4.5  245  34 18   7.8   4.3 | -20.6  -5.1  265  39 20   8.0   4.4
 24000 -18.2  -0.8  245  34 18   6.9   3.8 | -18.3  -0.9  265  39 20   7.5   4.1
 23000 -16.1   3.0  250  35 18   6.9   3.8 | -16.1   3.0  265  38 20   7.5   4.1
 22000 -14.1   6.6  250  35 18   6.9   3.8 | -13.9   7.0  265  37 19   7.5   4.1
 21000 -12.1  10.2  255  36 19   6.6   3.6 | -12.3   9.9  265  37 19   5.1   2.8
 20000 -10.1  13.8  255  37 19   6.6   3.6 | -10.8  12.6  270  38 19   5.2   2.8
 19500  -9.1  15.6  260  38 19   6.7   3.7 | -10.0  14.0  270  38 20   5.1   2.8
 19000  -8.2  17.2  260  38 19   5.9   3.2 |  -9.2  15.4  270  38 20   5.8   3.2
 18500  -7.3  18.9  265  36 19   5.8   3.2 |  -8.3  17.1  270  37 19   6.0   3.3
 18000  -6.4  20.5  265  35 18   5.7   3.1 |  -7.5  18.5  270  36 18   6.1   3.4
 17500  -5.6  21.9  270  34 18   5.2   2.9 |  -6.5  20.3  270  34 17   6.9   3.8
 17000  -4.9  23.2  270  34 17   5.3   2.9 |  -5.6  21.9  270  32 16   6.9   3.8
 16500  -4.2  24.4  270  32 17   5.6   3.1 |  -4.6  23.7  270  30 15   7.1   3.9
 16000  -3.4  25.9  270  30 15   5.8   3.2 |  -3.6  25.5  265  27 14   7.1   3.9
 15500  -2.7  27.1  275  27 14   6.6   3.6 |  -2.6  27.3  265  24 12   7.2   4.0
 15000  -1.2  29.8  275  22 11   7.3   4.0 |  -1.0  30.2  265  20 10   7.4   4.0
 14500  -0.1  31.8  280  18  9   8.0   4.4 |   0.1  32.2  260  18  9   7.5   4.1
 14000   1.1  34.0  280  16  8   8.2   4.5 |   1.1  34.0  260  16  8   7.5   4.1
 13500   2.3  36.1  280  14  7   7.9   4.3 |   2.2  36.0  255  15  8   7.8   4.3
 13000   3.4  38.1  280  13  7   7.6   4.2 |   3.4  38.1  250  14  7   8.1   4.5
 12500   4.5  40.1  275  11  6   7.6   4.2 |   4.6  40.3  245  12  6   8.0   4.4
 12000   5.6  42.1  270   9  5   7.7   4.2 |   5.7  42.3  245  11  6   7.6   4.2
 11500   6.7  44.1  260   8  4   7.7   4.2 |   6.9  44.4  245  10  5   7.9   4.4
 11000   7.9  46.2  250   7  4   7.5   4.1 |   8.2  46.8  235   8  4   8.8   4.8
 10500   9.0  48.2  240   7  4   3.3   1.8 |   9.5  49.1  220   7  4   4.5   2.4
 10250   9.1  48.4  235   7  4   4.8   2.6 |   9.6  49.3  215   7  4   5.6   3.1
 10000   9.8  49.6  230   7  4  11.5   6.3 |  10.4  50.7  205   7  4  12.2   6.7
  9750  10.5  50.9  220   7  4  10.1   5.6 |  11.2  52.2  195   7  4  11.0   6.0
  9500  11.3  52.3  215   7  4   9.2   5.0 |  11.9  53.4  190   7  4   9.5   5.2
  9250  11.8  53.2  205   7  4   7.5   4.1 |  12.5  54.5  185   8  4   6.9   3.8
  9000  12.4  54.3  195   7  4   9.1   5.0 |  13.0  55.4  180   8  4   9.0   5.0
  8750  13.1  55.6  190   7  4  10.1   5.6 |  13.8  56.8  175   8  4  10.6   5.8
  8500  13.7  56.7  180   7  4   9.7   5.3 |  14.5  58.1  175   8  4   9.8   5.4
  8250  14.4  57.9  180   7  4   9.6   5.3 |  15.2  59.4  170   8  4   9.3   5.1
  8000  15.1  59.2  175   7  4   9.7   5.3 |  15.9  60.6  170   8  4   9.6   5.3
  7750  15.9  60.6  175   7  4   9.8   5.4 |  16.6  61.9  170   8  4   9.8   5.4
  7500  16.6  61.9  175   7  4  10.0   5.5 |  17.4  63.3  170   7  4   9.9   5.4
  7250  17.3  63.1  175   7  4  10.1   5.5 |  18.1  64.6  170   7  4  10.1   5.5
  7000  18.1  64.6  175   7  4  10.1   5.6 |  18.8  65.8  170   7  4   9.9   5.4
  6750  18.9  66.0  175   7  3  10.6   5.8 |  19.6  67.3  170   7  4   9.7   5.3
  6500  19.6  67.3  175   7  3  10.7   5.9 |  20.3  68.5  170   7  3   9.9   5.4
  6250  20.4  68.7  175   6  3  11.3   6.2 |  21.1  70.0  170   6  3   9.9   5.4
  6000  21.3  70.3  170   6  3   9.0   4.9 |  21.8  71.2  170   6  3  10.4   5.7
  5750  22.0  71.6  170   6  3  12.8   7.0 |  22.6  72.7  170   6  3  10.6   5.8
  5500  23.4  74.1  170   6  3  26.1  14.3 |  23.3  73.9  165   5  3   9.3   5.1
________________________________________________________________________________

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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