Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240122
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1922 MDT Wednesday, July 23, 2014

This forecast is for Thursday, July 24, 2014:

If the trigger temperature of 90.3 F/32.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 681 ft/min (3.5 m/s)
   Maximum height of thermals.................. 13031 ft MSL (7744 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 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................. 6739 ft MSL (1451 ft AGL)
Thermal soaring outlook for Friday 07/25....... 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....................... 15861 ft MSL (10574 ft AGL)
Wave soaring outlook for Friday 07/25.......... Poor

Remarks... Large upper level ridge remaining over colorado with weak westerly
           flow aloft. Round of afternoon thunderstorms expected Thursday.

Sunrise/Sunset.................... 05:51:23 / 20:20:48 MDT
Total possible sunshine........... 14 hr 29 min 24 sec (869 min 24 sec)
Altitude of sun at 13:05:56 MDT... 69.96 degrees

Upper air data from numerical model forecast valid on 07/24/2014 at 0600 MDT

Freezing level.................. 17277 ft MSL (11990 ft AGL)
Convective condensation level... 17967 ft MSL (12680 ft AGL)
Lifted condensation level....... 17113 ft MSL (11825 ft AGL)
Lifted index.................... -2.3
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  -67.9 -90.2   280   31   16   3.5   1.9      M     M       M      M    M
 45000  -60.8 -77.4   290   43   22   6.0   3.3      M     M       M      M    M
 40000  -51.2 -60.2   290   49   25   7.7   4.2      M     M       M      M    M
 38000  -46.6 -51.9   290   46   24   7.7   4.2      M     M       M      M    M
 36000  -42.0 -43.6   290   43   22   7.8   4.3      M     M       M      M    M
 34000  -37.3 -35.1   280   40   20   7.9   4.3      M     M       M      M    M
 32000  -32.5 -26.5   275   37   19   8.5   4.7      M     M       M      M    M
 30000  -27.8 -18.0   280   27   14   7.0   3.9   47.5 117.6    10.3      M    M
 29000  -25.7 -14.3   285   22   11   7.0   3.9   46.6 115.9     9.7      M    M
 28000  -23.7 -10.7   285   18    9   6.5   3.6   45.5 113.9     8.9      M    M
 27000  -21.8  -7.2   285   15    8   6.5   3.6   44.2 111.5     7.9      M    M
 26000  -19.9  -3.8   280   11    6   6.5   3.6   43.0 109.3     7.1      M    M
 25000  -17.9  -0.2   270    9    4   6.8   3.7   41.9 107.4     6.2      M    M
 24000  -15.9   3.4   260    8    4   6.8   3.7   40.7 105.2     5.3      M    M
 23000  -13.9   7.0   250    9    4   6.8   3.7   39.6 103.3     4.4      M    M
 22000  -11.8  10.8   240    9    5   8.3   4.5   38.7 101.7     3.7      M    M
 21000   -9.4  15.1   245   11    5   8.2   4.5   38.1 100.6     3.3      M    M
 20000   -6.9  19.6   250   12    6   8.2   4.5   37.6  99.7     2.9      M    M
 19500   -5.6  21.9   250   12    6   8.3   4.5   37.4  99.3     2.7      M    M
 19000   -4.4  24.1   250   12    6   8.3   4.6   37.1  98.9     2.5      M    M
 18500   -3.2  26.2   250   12    6   8.3   4.6   36.9  98.4     2.3      M    M
 18000   -1.9  28.6   245   11    6   8.2   4.5   36.6  98.0     2.1      M    M
 17500   -0.7  30.7   245   11    6   8.2   4.5   36.4  97.5     1.8      M    M
 17000    0.4  32.7   240   11    6   8.3   4.5   36.1  97.0     1.6      M    M
 16500    1.7  35.1   235   12    6   8.3   4.6   35.9  96.6     1.3      M    M
 16000    2.9  37.2   235   12    6   8.3   4.6   35.6  96.1     1.1      M    M
 15500    4.2  39.6   230   13    7   8.9   4.9   35.4  95.8     0.9      M    M
 15000    6.1  43.0   230   13    7   8.9   4.9   35.2  95.4     0.7      M    M
 14500    7.4  45.3   230   13    7   8.9   4.9   35.1  95.1     0.5      M    M
 14000    8.6  47.5   230   13    7   8.9   4.9   34.9  94.9     0.3      M    M
 13500    9.9  49.8   235   12    6   9.2   5.0   34.8  94.7     0.1      M    M
 13000   11.2  52.2   235   12    6   9.1   5.0   34.7  94.5    -0.0    668  3.4
 12500   12.6  54.7   240   11    6   9.8   5.4   34.7  94.4    -0.1    613  3.1
 12000   14.0  57.2   245   11    6   9.9   5.4   34.7  94.5    -0.1    554  2.8
 11500   15.5  59.9   250   11    6   9.2   5.0   34.7  94.5    -0.2    497  2.5
 11000   16.8  62.2   250   11    6   9.2   5.0   34.6  94.2    -0.3    442  2.2
 10500   17.9  64.2   250   11    6   4.7   2.6   34.3  93.7    -0.6    394  2.0
 10250   18.2  64.8   250   11    6   7.1   3.9   33.9  93.0    -1.0    376  1.9
 10000   19.0  66.2   250   11    6  10.6   5.8   33.9  93.0    -1.1    348  1.8
  9750   19.7  67.5   250   11    6   9.7   5.3   33.9  93.0    -1.1    319  1.6
  9500   20.3  68.5   250   11    6   6.5   3.5   33.8  92.9    -1.2    292  1.5
  9250   20.7  69.3   250   11    6   5.6   3.1   33.4  92.2    -1.5    274  1.4
  9000   21.2  70.2   255   11    6   8.5   4.7   33.3  91.9    -1.7    250  1.3
  8750   21.9  71.4   255   11    6   8.6   4.7   33.2  91.7    -1.8    224  1.1
  8500   22.5  72.5   260   11    6   8.4   4.6   33.1  91.6    -1.9    198  1.0
  8250   23.1  73.6   265   11    6   8.1   4.4   33.0  91.3    -2.0    172  0.9
  8000   23.7  74.7   265   11    6   9.3   5.1   32.9  91.2    -2.2    146  0.7
  7750   24.4  75.9   270   12    6   9.5   5.2   32.9  91.2    -2.2    117  0.6
  7500   25.0  77.0   275   13    6   7.7   4.2   32.8  91.0    -2.3     91  0.5
  7250   25.6  78.1   280   14    7   6.8   3.7   32.6  90.6    -2.5     67  0.3
  7000   26.1  79.0   280   16    8   8.8   4.8   32.4  90.3    -2.7     44  0.2
  6750   26.6  79.9   285   18    9   1.8   1.0   32.2  90.0    -2.9     22  0.1
  6500   26.3  79.3   280   17    9  -6.4  -3.5   31.2  88.1    -4.0     25  0.1
  6250   25.7  78.3   275   15    8  -9.0  -4.9   29.9  85.8    -5.3     34  0.2
  6000   25.2  77.4   270   13    7   1.0   0.6   28.6  83.6    -6.6     43  0.2
  5750   25.4  77.7   265   13    6  -9.2  -5.0   28.1  82.6    -7.1     30  0.2
  5500   22.8  73.0   245    8    4 -55.4 -30.4   24.9  76.9   -10.4     99  0.5

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

           07/24/2014 at 0900 MDT          |       07/24/2014 at 1200 MDT
                                           |
K index... +21.9  LI... -0.7               | K index... +22.8  LI... -1.9
CAPE... +140.9  CIN... -185.0              | CAPE... +385.6  CIN... -36.4
                                           |
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 -66.9 -88.4  285  30 15   2.4   1.3 | -67.2 -89.0  285  31 16   2.1   1.2
 45000 -61.3 -78.3  285  42 22   6.2   3.4 | -61.7 -79.1  285  46 24   6.5   3.6
 40000 -51.3 -60.3  290  49 25   7.3   4.0 | -51.2 -60.2  285  53 27   7.4   4.1
 38000 -46.9 -52.4  290  43 22   7.3   4.0 | -46.7 -52.1  280  47 24   7.4   4.1
 36000 -42.5 -44.5  285  37 19   7.7   4.2 | -42.3 -44.1  280  41 21   7.7   4.2
 34000 -37.8 -36.0  280  32 17   7.9   4.3 | -37.6 -35.7  275  33 17   7.9   4.3
 32000 -33.0 -27.4  265  28 14   8.7   4.8 | -32.9 -27.2  270  26 13   8.4   4.6
 30000 -28.5 -19.3  265  21 11   7.7   4.2 | -28.1 -18.6  265  23 12   8.0   4.4
 29000 -25.7 -14.3  260  17  9   7.6   4.2 | -25.2 -13.4  260  21 11   8.0   4.4
 28000 -23.6 -10.5  255  15  8   6.4   3.5 | -23.0  -9.4  255  20 11   6.5   3.6
 27000 -21.7  -7.1  250  13  7   6.4   3.5 | -21.1  -6.0  245  21 11   6.5   3.6
 26000 -19.8  -3.6  245  12  6   6.5   3.5 | -19.2  -2.6  240  22 11   6.5   3.6
 25000 -17.9  -0.2  235  11  6   6.2   3.4 | -17.3   0.9  235  22 11   6.5   3.5
 24000 -16.0   3.2  230  12  6   6.2   3.4 | -15.3   4.5  240  21 11   6.5   3.6
 23000 -14.2   6.4  230  13  7   6.2   3.4 | -13.3   8.1  240  20 11   6.5   3.6
 22000 -12.2  10.0  230  13  7   8.5   4.7 | -11.3  11.7  240  19 10   7.2   4.0
 21000  -9.6  14.7  235  14  7   8.5   4.7 |  -9.2  15.4  240  17  9   7.3   4.0
 20000  -7.1  19.2  245  15  8   8.5   4.7 |  -7.0  19.4  240  15  8   7.3   4.0
 19500  -5.8  21.6  250  16  8   8.4   4.6 |  -6.0  21.2  235  14  7   8.1   4.4
 19000  -4.6  23.7  250  16  8   8.4   4.6 |  -4.6  23.7  240  13  7   9.1   5.0
 18500  -3.4  25.9  255  17  9   8.4   4.6 |  -3.3  26.1  240  12  6   9.2   5.1
 18000  -2.1  28.2  255  17  9   8.6   4.7 |  -2.0  28.4  240  11  6   8.0   4.4
 17500  -0.9  30.4  260  16  8   8.6   4.7 |  -0.9  30.4  240  10  5   8.0   4.4
 17000   0.4  32.7  260  16  8   8.5   4.6 |   0.3  32.5  245   9  5   8.0   4.4
 16500   1.6  34.9  260  15  8   8.3   4.5 |   1.4  34.5  240   8  4   8.0   4.4
 16000   2.8  37.0  255  14  7   8.3   4.5 |   2.6  36.7  240   7  4   7.9   4.3
 15500   4.0  39.2  255  13  7   8.5   4.7 |   3.8  38.8  235   7  4   8.8   4.8
 15000   5.2  41.4  255  12  6   8.5   4.6 |   5.0  41.0  230   7  4   8.8   4.8
 14500   7.1  44.8  250  11  5   9.1   5.0 |   6.9  44.4  230   7  3   8.3   4.6
 14000   8.5  47.3  250  10  5   9.2   5.1 |   8.1  46.6  225   6  3   8.4   4.6
 13500   9.7  49.5  250   9  5   8.4   4.6 |   9.3  48.7  230   6  3   8.3   4.5
 13000  10.9  51.6  245   9  4   8.4   4.6 |  10.5  50.9  235   6  3   8.3   4.5
 12500  12.2  54.0  245   8  4   8.8   4.9 |  11.7  53.1  240   5  3   8.8   4.8
 12000  13.5  56.3  245   8  4   8.9   4.9 |  13.0  55.4  255   6  3   8.9   4.9
 11500  14.7  58.5  250   8  4   8.5   4.7 |  14.4  57.9  265   6  3   8.8   4.8
 11000  16.0  60.8  250   8  4   8.5   4.6 |  15.6  60.1  275   7  4   8.9   4.9
 10500  17.1  62.8  255   8  4   4.7   2.6 |  16.8  62.2  285   9  5   5.2   2.9
 10250  17.5  63.5  255   8  4   7.8   4.3 |  17.1  62.8  285   9  5   7.8   4.3
 10000  18.3  64.9  260   8  4  11.5   6.3 |  17.9  64.2  290  10  5  11.0   6.1
  9750  19.0  66.2  260   8  4  10.6   5.8 |  18.6  65.5  290  11  5  10.3   5.7
  9500  19.8  67.6  265   8  4   8.3   4.6 |  19.3  66.7  295  11  6   8.3   4.6
  9250  20.3  68.5  265   8  4   8.0   4.4 |  19.8  67.6  295  11  5   8.4   4.6
  9000  21.0  69.8  265   9  4  10.5   5.8 |  20.5  68.9  300  10  5  11.0   6.0
  8750  21.8  71.2  265   9  5  10.5   5.8 |  21.3  70.3  300  10  5  10.8   5.9
  8500  22.6  72.7  270  10  5   9.3   5.1 |  22.0  71.6  300   9  5   9.8   5.4
  8250  23.2  73.8  270  10  5   8.7   4.8 |  22.7  72.9  300   9  5   9.0   4.9
  8000  23.8  74.8  275  11  6   8.2   4.5 |  23.4  74.1  300   9  5  10.0   5.5
  7750  24.4  75.9  275  13  7   6.8   3.7 |  24.2  75.6  300   9  5  10.6   5.8
  7500  24.9  76.8  280  14  7   5.5   3.0 |  25.0  77.0  300   9  5  10.3   5.6
  7250  25.2  77.4  280  14  7   4.6   2.5 |  25.8  78.4  300   9  5  10.5   5.7
  7000  25.5  77.9  280  15  7   5.6   3.1 |  26.5  79.7  300   9  5   9.7   5.3
  6750  25.9  78.6  280  15  8   4.6   2.5 |  27.2  81.0  300   9  5   9.7   5.3
  6500  26.1  79.0  275  13  6   2.2   1.2 |  28.0  82.4  300   9  5  10.7   5.9
  6250  26.2  79.2  265  10  5   2.8   1.6 |  28.8  83.8  300   9  5  11.2   6.2
  6000  26.3  79.3  255   7  4   0.2   0.1 |  29.6  85.3  300   9  4   9.7   5.3
  5750  26.2  79.2  225   5  2   6.2   3.4 |  30.4  86.7  300   9  4  15.3   8.4
  5500  27.3  81.1  225   4  2  24.0  13.2 |  32.1  89.8  300   8  4  28.8  15.8

           07/24/2014 at 1500 MDT          |       07/24/2014 at 1800 MDT
                                           |
K index... +27.3  LI... -1.4               | K index... +27.0  LI... -1.6
CAPE... +260.5  CIN... -30.7               | CAPE... +160.0  CIN... -72.7
                                           |
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 -67.2 -89.0  285  35 18   1.6   0.9 | -67.7 -89.9  280  37 19   1.2   0.7
 45000 -62.3 -80.1  285  52 27   6.4   3.5 | -63.0 -81.4  285  54 28   6.8   3.7
 40000 -51.6 -60.9  285  56 29   8.1   4.5 | -51.8 -61.2  285  52 27   8.3   4.6
 38000 -46.7 -52.1  280  50 26   8.1   4.5 | -46.8 -52.2  275  46 24   8.3   4.6
 36000 -41.9 -43.4  275  44 23   8.2   4.5 | -41.9 -43.4  270  41 21   8.4   4.6
 34000 -36.9 -34.4  275  40 20   8.2   4.5 | -36.8 -34.2  270  39 20   8.4   4.6
 32000 -32.0 -25.6  270  35 18   8.8   4.8 | -31.8 -25.2  270  37 19   9.1   5.0
 30000 -27.7 -17.9  260  30 16   7.1   3.9 | -27.2 -17.0  265  36 19   7.8   4.3
 29000 -25.6 -14.1  255  28 15   7.1   3.9 | -24.9 -12.8  265  36 19   7.8   4.3
 28000 -23.0  -9.4  250  27 14   7.2   4.0 | -22.2  -8.0  260  36 18   6.5   3.6
 27000 -20.8  -5.4  245  27 14   7.2   4.0 | -20.3  -4.5  260  34 18   6.5   3.6
 26000 -18.7  -1.7  240  27 14   7.2   4.0 | -18.4  -1.1  260  33 17   6.6   3.6
 25000 -16.6   2.1  240  27 14   6.4   3.5 | -16.5   2.3  255  32 16   5.6   3.0
 24000 -14.6   5.7  235  27 14   6.3   3.5 | -14.9   5.2  250  30 16   5.4   3.0
 23000 -12.7   9.1  235  27 14   6.4   3.5 | -13.4   7.9  245  29 15   5.4   3.0
 22000 -10.7  12.7  235  26 13   6.9   3.8 | -11.7  10.9  240  28 15   7.5   4.1
 21000  -8.6  16.5  225  23 12   6.9   3.8 |  -9.4  15.1  235  25 13   7.8   4.3
 20000  -6.5  20.3  220  20 10   7.0   3.8 |  -7.2  19.0  230  22 11   7.9   4.3
 19500  -5.5  22.1  215  19 10   7.0   3.9 |  -6.1  21.0  225  21 11   7.6   4.1
 19000  -4.5  23.9  210  18  9   7.2   4.0 |  -5.0  23.0  225  19 10   6.8   3.7
 18500  -3.4  25.9  205  17  9   7.2   4.0 |  -4.0  24.8  225  18  9   6.8   3.7
 18000  -2.3  27.9  200  16  8   8.1   4.5 |  -3.0  26.6  225  17  9   7.1   3.9
 17500  -1.2  29.8  200  16  8   8.3   4.6 |  -2.0  28.4  220  17  9   7.2   4.0
 17000   0.0  32.0  200  15  8   8.4   4.6 |  -0.9  30.4  220  16  8   7.4   4.1
 16500   1.1  34.0  200  15  8   8.2   4.5 |   0.2  32.4  220  15  8   8.1   4.4
 16000   2.3  36.1  195  14  7   8.4   4.6 |   1.4  34.5  220  15  8   8.1   4.4
 15500   3.4  38.1  195  13  6   8.2   4.5 |   2.6  36.7  220  14  7   7.8   4.3
 15000   4.5  40.1  195  11  6   8.3   4.5 |   3.7  38.7  225  13  7   7.9   4.3
 14500   6.2  43.2  195   8  4   7.5   4.1 |   4.9  40.8  225  13  7   8.1   4.4
 14000   7.3  45.1  205   5  3   7.6   4.2 |   6.7  44.1  235  11  6   8.1   4.4
 13500   8.3  46.9  235   3  1   7.6   4.2 |   7.9  46.2  240  11  6   9.1   5.0
 13000   9.4  48.9  300   3  2   7.6   4.2 |   9.3  48.7  245  10  5   9.1   5.0
 12500  10.6  51.1  325   5  3   8.3   4.5 |  10.6  51.1  255  10  5   9.0   5.0
 12000  11.8  53.2  325   8  4   8.5   4.6 |  12.0  53.6  265  10  5   9.0   4.9
 11500  13.1  55.6  330  11  6   9.4   5.1 |  13.3  55.9  275  10  5   9.0   5.0
 11000  14.5  58.1  325  12  6   9.9   5.4 |  14.7  58.5  285  10  5   9.0   4.9
 10500  15.8  60.4  325  13  7   5.5   3.0 |  16.0  60.8  295  11  6   4.7   2.6
 10250  16.2  61.2  325  13  7   8.4   4.6 |  16.3  61.3  295  12  6   6.8   3.7
 10000  17.1  62.8  325  14  7  13.1   7.2 |  17.1  62.8  300  14  7  11.5   6.3
  9750  18.0  64.4  325  14  7  12.3   6.8 |  17.9  64.2  305  15  8  10.7   5.8
  9500  18.9  66.0  325  14  7   9.0   4.9 |  18.6  65.5  305  17  9   7.8   4.3
  9250  19.4  66.9  325  14  7   8.0   4.4 |  19.1  66.4  305  19 10   6.2   3.4
  9000  20.2  68.4  325  14  7  11.2   6.1 |  19.7  67.5  310  21 11   8.6   4.7
  8750  21.0  69.8  325  15  7  11.0   6.0 |  20.3  68.5  310  23 12   8.6   4.7
  8500  21.8  71.2  325  15  8  10.3   5.7 |  20.9  69.6  310  25 13   7.4   4.0
  8250  22.5  72.5  325  15  8   9.8   5.4 |  21.3  70.3  310  25 13   6.8   3.8
  8000  23.3  73.9  325  15  8   9.7   5.3 |  21.7  71.1  310  26 13   6.2   3.4
  7750  24.0  75.2  325  15  8   9.6   5.3 |  22.0  71.6  310  24 12   6.3   3.5
  7500  24.7  76.5  320  15  8  10.2   5.6 |  22.5  72.5  305  23 12   9.1   5.0
  7250  25.5  77.9  320  15  8  10.5   5.8 |  23.3  73.9  310  22 12  10.4   5.7
  7000  26.3  79.3  320  15  8  10.1   5.5 |  24.0  75.2  310  22 11   9.4   5.2
  6750  27.0  80.6  320  15  8  10.2   5.6 |  24.6  76.3  310  21 11   9.3   5.1
  6500  27.8  82.0  320  15  8  10.6   5.8 |  25.4  77.7  310  21 11  10.3   5.6
  6250  28.6  83.5  320  15  8  11.3   6.2 |  26.2  79.2  310  20 10  10.6   5.8
  6000  29.4  84.9  320  15  8   9.3   5.1 |  26.9  80.4  310  19 10   9.7   5.3
  5750  30.2  86.4  320  15  8  14.6   8.0 |  27.7  81.9  310  19 10  10.6   5.8
  5500  31.8  89.2  320  14  7  28.9  15.8 |  28.6  83.5  310  16  8  14.6   8.0
________________________________________________________________________________

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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