Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240024
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1824 MDT Monday, May 23, 2016

This forecast is for Tuesday, May 24, 2016:

If the trigger temperature of 67.5 F/19.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1045 ft/min (5.3 m/s)
   Maximum height of thermals.................. 16967 ft MSL (11660 ft AGL)

Forecast maximum temperature................... 77.0 F/25.5 C
Time of trigger temperature.................... 1030 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................. 11932 ft MSL (6625 ft AGL)
Thermal soaring outlook for Wednesday 05/25.... 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....................... 39217 ft MSL (33910 ft AGL)
Wave soaring outlook for Wednesday 05/25....... Poor

Remarks...

Sunrise/Sunset.................... 05:37:34 / 20:15:02 MDT
Total possible sunshine........... 14 hr 37 min 29 sec (877 min 29 sec)
Altitude of sun at 12:56:29 MDT... 71.16 degrees

Upper air data from numerical model forecast valid on 05/24/2016 at 0600 MDT

Freezing level.................. 12646 ft MSL (7339 ft AGL)
Convective condensation level... 14174 ft MSL (8867 ft AGL)
Lifted condensation level....... 15150 ft MSL (9843 ft AGL)
Lifted index.................... -3.1
K index......................... +13.7

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  -59.1 -74.4   255   29   15   0.3   0.2      M     M       M      M    M
 45000  -58.6 -73.5   250   42   22   1.0   0.6      M     M       M      M    M
 40000  -57.1 -70.8   240   61   31   1.1   0.6      M     M       M      M    M
 38000  -54.7 -66.5   240   63   33   4.9   2.7      M     M       M      M    M
 36000  -51.8 -61.2   240   64   33   4.9   2.7      M     M       M      M    M
 34000  -48.3 -54.9   240   64   33   7.3   4.0      M     M       M      M    M
 32000  -44.0 -47.2   240   63   32   7.2   4.0      M     M       M      M    M
 30000  -39.1 -38.4   240   59   30   7.2   3.9   36.3  97.4     8.6      M    M
 29000  -37.0 -34.6   240   56   29   7.2   3.9   35.3  95.5     7.9      M    M
 28000  -34.9 -30.8   240   53   27   7.2   4.8   34.4  93.8     7.2      M    M
 27000  -32.7 -26.9   240   50   26   7.5   4.1   33.5  92.2     6.6      M    M
 26000  -30.4 -22.7   240   49   25   7.5   4.1   32.5  90.6     5.9      M    M
 25000  -28.2 -18.8   240   47   24   7.5   4.1   31.7  89.1     5.4      M    M
 24000  -25.9 -14.6   240   46   24   7.6   4.2   31.0  87.8     4.8      M    M
 23000  -23.7 -10.7   240   44   23   7.6   4.2   30.1  86.2     4.1      M    M
 22000  -21.4  -6.5   240   42   21   7.6   4.2   29.4  84.9     3.5      M    M
 21000  -19.2  -2.6   240   40   20   7.8   4.3   28.7  83.6     2.9      M    M
 20000  -16.8   1.8   240   38   20   7.8   4.3   27.9  82.3     2.3      M    M
 19500  -15.7   3.7   240   37   19   7.8   4.3   27.6  81.7     2.1      M    M
 19000  -14.5   5.9   240   36   19   7.9   4.3   27.3  81.1     1.8      M    M
 18500  -13.4   7.9   240   35   18   7.0   3.9   26.9  80.5     1.5      M    M
 18000  -12.3   9.9   240   34   17   7.0   3.8   26.5  79.6     1.1      M    M
 17500  -11.3  11.7   240   32   17   6.6   3.6   26.0  78.8     0.7      M    M
 17000  -10.4  13.3   240   31   16   5.9   3.2   25.4  77.6     0.2      M    M
 16500   -9.5  14.9   240   29   15   5.7   3.1   24.7  76.5    -0.4   1015  5.2
 16000   -8.5  16.7   245   28   14   8.2   4.5   24.2  75.6    -0.9    971  4.9
 15500   -6.8  19.8   245   26   13   8.1   4.4   23.8  74.8    -1.4    897  4.6
 15000   -5.6  21.9   245   24   12   8.2   4.5   23.5  74.3    -1.7    847  4.3
 14500   -4.4  24.1   250   23   12   8.3   4.5   23.3  73.9    -1.9    796  4.0
 14000   -3.2  26.2   250   21   11   8.0   4.4   23.0  73.4    -2.2    745  3.8
 13500   -2.0  28.4   255   19   10   7.9   4.4   22.7  72.9    -2.5    695  3.5
 13000   -0.8  30.6   255   17    9   8.9   4.9   22.5  72.5    -2.7    643  3.3
 12500    0.6  33.1   250   14    7   9.0   5.0   22.4  72.2    -2.8    588  3.0
 12000    1.9  35.4   250   12    6   8.1   4.5   22.2  72.0    -3.0    534  2.7
 11500    3.1  37.6   245   10    5   7.8   4.3   21.9  71.4    -3.3    484  2.5
 11000    4.2  39.6   240    8    4   7.0   3.8   21.6  70.8    -3.7    436  2.2
 10500    5.2  41.4   235    6    3   6.1   3.3   21.1  69.9    -4.2    391  2.0
 10250    5.7  42.3   235    5    3   9.1   5.0   20.8  69.5    -4.4    369  1.9
 10000    6.4  43.5   225    4    2   9.3   5.1   20.9  69.6    -4.4    339  1.7
  9750    6.9  44.4   220    4    2   6.3   3.5   20.7  69.2    -4.6    317  1.6
  9500    7.4  45.3   215    3    2   7.3   4.0   20.5  68.8    -4.9    295  1.5
  9250    7.9  46.2   205    3    1   6.5   3.6   20.3  68.5    -5.2    273  1.4
  9000    8.3  46.9   190    2    1   6.8   3.7   20.0  68.0    -5.5    253  1.3
  8750    8.8  47.8   185    2    1   7.5   4.1   19.8  67.6    -5.7    230  1.2
  8500    9.3  48.7   180    2    1   7.5   4.1   19.6  67.3    -6.0    208  1.1
  8250    9.8  49.6   170    2    1   6.9   3.8   19.4  67.0    -6.2    186  0.9
  8000   10.2  50.4   175    1    1   5.4   3.0   19.2  66.5    -6.5    165  0.8
  7750   10.6  51.1   185    1    1   4.5   2.5   18.8  65.8    -6.9    148  0.8
  7500   10.9  51.6   195    1    0   4.3   2.4   18.4  65.1    -7.4    131  0.7
  7250   11.2  52.2   205    1    0   4.2   2.3   18.0  64.3    -7.8    115  0.6
  7000   11.5  52.7   155    1    0   3.9   2.2   17.5  63.6    -8.3     99  0.5
  6750   11.7  53.1   125    1    1   3.1   1.7   17.1  62.7    -8.8     85  0.4
  6500   11.9  53.4   115    2    1   0.8   0.4   16.5  61.7    -9.4     73  0.4
  6250   11.8  53.2   135    2    1  -1.9  -1.1   15.7  60.2   -10.2     68  0.3
  6000   11.5  52.7   185    2    1  -3.2  -1.8   14.7  58.5   -11.2     68  0.3
  5750   11.3  52.3   215    2    1  -1.2  -0.6   13.8  56.9   -12.2     67  0.3
  5500   10.9  51.6   225    3    2 -15.1  -8.3   12.7  54.9   -13.4     73  0.4

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

           05/24/2016 at 0900 MDT          |       05/24/2016 at 1200 MDT
                                           |
K index... +7.6  LI... +1.0                | K index... +8.8  LI... -3.4
CAPE... 0.0  CIN... -4.6                   | CAPE... +644.5  CIN... -20.0
                                           |
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 -58.4 -73.1  250  29 15   0.2   0.1 | -57.9 -72.2  250  19 10   0.6   0.3
 45000 -58.0 -72.4  245  45 23   0.3   0.2 | -57.0 -70.6  240  31 16  -0.0  -0.0
 40000 -57.6 -71.7  240  61 32   0.4   0.2 | -57.1 -70.8  240  60 31   0.1   0.0
 38000 -55.2 -67.4  240  62 32   5.1   2.8 | -55.0 -67.0  235  63 33   4.9   2.7
 36000 -52.2 -62.0  235  62 32   5.1   2.8 | -52.1 -61.8  235  63 33   4.9   2.7
 34000 -48.7 -55.7  230  61 31   7.2   4.0 | -48.7 -55.7  230  62 32   6.9   3.8
 32000 -44.3 -47.7  230  58 30   7.2   3.9 | -44.0 -47.2  230  59 30   6.9   3.8
 30000 -39.2 -38.6  230  56 29   8.1   4.4 | -39.6 -39.3  225  55 28   7.9   4.3
 29000 -36.8 -34.2  230  55 28   8.1   4.4 | -37.2 -35.0  225  54 28   7.9   4.3
 28000 -34.4 -29.9  230  53 27   8.1   4.4 | -34.9 -30.8  225  52 27   7.9   4.3
 27000 -32.1 -25.8  230  51 26   6.7   3.7 | -32.5 -26.5  225  50 26   7.5   4.1
 26000 -30.1 -22.2  230  48 25   6.7   3.7 | -30.3 -22.5  225  48 25   7.5   4.1
 25000 -28.1 -18.6  230  44 23   6.7   3.7 | -28.0 -18.4  225  46 24   7.5   4.1
 24000 -26.0 -14.8  225  41 21   8.1   4.4 | -25.8 -14.4  220  43 22   7.1   3.9
 23000 -23.6 -10.5  230  40 20   8.0   4.4 | -23.7 -10.7  220  41 21   7.1   3.9
 22000 -21.2  -6.2  230  38 20   8.0   4.4 | -21.6  -6.9  220  39 20   7.1   3.9
 21000 -18.9  -2.0  230  37 19   7.3   4.0 | -19.4  -2.9  215  38 19   8.2   4.5
 20000 -16.7   1.9  230  35 18   7.4   4.1 | -17.0   1.4  215  36 18   8.1   4.5
 19500 -15.6   3.9  230  35 18   7.4   4.1 | -15.8   3.6  215  35 18   8.1   4.5
 19000 -14.5   5.9  230  34 17   7.4   4.1 | -14.6   5.7  215  34 17   8.1   4.4
 18500 -13.4   7.9  235  33 17   7.8   4.3 | -13.4   7.9  220  33 17   8.5   4.7
 18000 -12.2  10.0  235  32 17   7.8   4.3 | -12.1  10.2  220  32 16   8.5   4.7
 17500 -11.1  12.0  235  31 16   7.8   4.3 | -10.8  12.6  220  30 16   8.2   4.5
 17000  -9.9  14.2  235  30 15   7.7   4.2 |  -9.1  15.6  225  29 15   7.7   4.3
 16500  -8.8  16.2  235  29 15   7.7   4.2 |  -7.9  17.8  225  27 14   8.0   4.4
 16000  -7.1  19.2  235  27 14   7.1   3.9 |  -6.7  19.9  225  26 13   8.1   4.5
 15500  -6.1  21.0  235  25 13   7.1   3.9 |  -5.5  22.1  225  25 13   8.1   4.4
 15000  -5.0  23.0  235  24 12   7.1   3.9 |  -4.3  24.3  225  24 12   7.7   4.2
 14500  -4.0  24.8  235  22 11   7.1   3.9 |  -3.2  26.2  225  23 12   7.8   4.3
 14000  -2.9  26.8  235  20 10   7.8   4.3 |  -2.1  28.2  220  21 11   7.1   3.9
 13500  -1.8  28.8  235  18  9   7.7   4.2 |  -1.0  30.2  215  20 10   7.1   3.9
 13000  -0.6  30.9  230  16  8   9.1   5.0 |   0.1  32.2  210  19 10   7.3   4.0
 12500   0.7  33.3  230  15  8   9.3   5.1 |   1.1  34.0  205  17  9   7.4   4.0
 12000   2.1  35.8  225  13  7   8.4   4.6 |   2.2  36.0  195  16  8   9.2   5.0
 11500   3.3  37.9  220  12  6   8.2   4.5 |   3.6  38.5  195  16  8   9.7   5.3
 11000   4.5  40.1  215  10  5   7.1   3.9 |   5.0  41.0  190  15  8   8.2   4.5
 10500   5.5  41.9  210   9  5   6.1   3.4 |   6.1  43.0  185  15  8   7.2   3.9
 10250   6.0  42.8  205   9  4   9.0   5.0 |   6.7  44.1  185  14  7  10.1   5.5
 10000   6.7  44.1  200   8  4   9.1   5.0 |   7.6  45.7  180  14  7   9.6   5.3
  9750   7.2  45.0  195   7  4   6.1   3.3 |   8.1  46.6  180  13  7   6.4   3.5
  9500   7.7  45.9  190   7  4   7.0   3.8 |   8.6  47.5  175  13  6   7.3   4.0
  9250   8.2  46.8  185   7  3   6.4   3.5 |   9.1  48.4  170  12  6   7.0   3.9
  9000   8.6  47.5  180   6  3   6.6   3.6 |   9.5  49.1  165  11  6   7.4   4.0
  8750   9.1  48.4  175   6  3   7.0   3.8 |   9.9  49.8  155  10  5   7.9   4.3
  8500   9.6  49.3  170   6  3   7.0   3.9 |  10.4  50.7  150   9  5   7.5   4.1
  8250  10.0  50.0  170   5  3   6.9   3.8 |  10.9  51.6  140   9  4   9.7   5.3
  8000  10.5  50.9  165   5  3   6.0   3.3 |  11.6  52.9  135   8  4  10.9   6.0
  7750  10.8  51.4  165   5  2   5.0   2.8 |  12.3  54.1  130   8  4   9.1   5.0
  7500  11.2  52.2  170   4  2   4.9   2.7 |  13.0  55.4  130   8  4   8.9   4.9
  7250  11.5  52.7  170   4  2   3.9   2.1 |  13.7  56.7  130   7  4   9.7   5.3
  7000  11.7  53.1  170   4  2   3.1   1.7 |  14.4  57.9  130   7  4  10.4   5.7
  6750  11.9  53.4  170   5  2   2.0   1.1 |  15.2  59.4  125   7  4   9.9   5.4
  6500  12.0  53.6  165   5  3   2.9   1.6 |  15.9  60.6  125   7  4  10.3   5.6
  6250  12.4  54.3  160   5  2   6.4   3.5 |  16.7  62.1  125   7  3  11.3   6.2
  6000  12.8  55.0  160   4  2   6.9   3.8 |  17.6  63.7  125   6  3  11.9   6.6
  5750  13.3  55.9  160   4  2   7.6   4.2 |  18.4  65.1  120   6  3   9.7   5.3
  5500  14.1  57.4  160   3  1  15.2   8.3 |  19.2  66.6  120   6  3  13.9   7.6

           05/24/2016 at 1500 MDT          |       05/24/2016 at 1800 MDT
                                           |
K index... +21.3  LI... -2.1               | K index... +23.8  LI... -3.2
CAPE... +416.3  CIN... -9.7                | CAPE... +500.9  CIN... -41.6
                                           |
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 -57.8 -72.0  235  17  9   0.7   0.4 | -57.8 -72.0  230  18  9   1.1   0.6
 45000 -56.7 -70.1  235  26 14   0.6   0.3 | -56.2 -69.2  230  27 14   0.6   0.3
 40000 -55.9 -68.6  240  63 32   0.6   0.4 | -55.3 -67.5  240  62 32   0.6   0.3
 38000 -54.1 -65.4  240  67 34   3.8   2.1 | -53.8 -64.8  240  65 34   3.4   1.9
 36000 -51.6 -60.9  235  66 34   3.8   2.1 | -51.5 -60.7  235  64 33   3.4   1.9
 34000 -48.4 -55.1  235  64 33   7.0   3.9 | -48.5 -55.3  235  62 32   7.1   3.9
 32000 -44.2 -47.6  230  61 31   7.0   3.9 | -44.2 -47.6  235  58 30   7.1   3.9
 30000 -39.8 -39.6  230  58 30   7.7   4.2 | -39.7 -39.5  235  54 28   7.9   4.3
 29000 -37.5 -35.5  230  56 29   7.7   4.2 | -37.3 -35.1  235  53 27   7.9   4.3
 28000 -35.1 -31.2  230  54 28   7.7   4.2 | -35.0 -31.0  235  52 27   7.9   4.3
 27000 -32.8 -27.0  230  53 27   7.6   4.2 | -32.6 -26.7  235  50 26   7.7   4.2
 26000 -30.5 -22.9  230  51 26   7.6   4.2 | -30.3 -22.5  240  48 24   7.7   4.2
 25000 -28.2 -18.8  230  49 25   7.6   4.2 | -28.0 -18.4  240  45 23   7.8   4.3
 24000 -26.0 -14.8  230  47 24   7.3   4.0 | -25.7 -14.3  240  43 22   7.2   4.0
 23000 -23.8 -10.8  230  44 23   7.3   4.0 | -23.6 -10.5  240  40 21   7.2   4.0
 22000 -21.6  -6.9  225  42 21   7.3   4.0 | -21.4  -6.5  235  37 19   7.3   4.0
 21000 -19.3  -2.7  225  40 20   8.7   4.7 | -19.2  -2.6  230  34 18   7.5   4.1
 20000 -16.7   1.9  225  39 20   8.6   4.7 | -17.0   1.4  225  32 16   7.5   4.1
 19500 -15.4   4.3  225  39 20   8.6   4.7 | -15.9   3.4  220  31 16   7.5   4.1
 19000 -14.2   6.4  225  39 20   8.6   4.7 | -14.8   5.4  215  30 16   7.4   4.1
 18500 -12.9   8.8  225  38 20   8.1   4.4 | -13.1   8.4  210  29 15   8.3   4.5
 18000 -11.1  12.0  225  35 18   8.1   4.5 | -11.9  10.6  205  29 15   8.3   4.5
 17500  -9.9  14.2  225  33 17   7.9   4.3 | -10.6  12.9  205  29 15   8.7   4.8
 17000  -8.8  16.2  220  31 16   7.9   4.3 |  -9.3  15.3  200  29 15   8.7   4.8
 16500  -7.6  18.3  215  29 15   8.2   4.5 |  -8.1  17.4  200  29 15   9.1   5.0
 16000  -6.4  20.5  210  27 14   8.5   4.6 |  -6.6  20.1  200  28 14   9.5   5.2
 15500  -5.1  22.8  200  25 13   8.5   4.7 |  -5.2  22.6  200  28 14   9.6   5.2
 15000  -3.9  25.0  195  23 12   8.8   4.8 |  -3.8  25.2  200  27 14   9.7   5.3
 14500  -2.6  27.3  190  21 11   8.9   4.9 |  -2.3  27.9  200  26 13   9.7   5.3
 14000  -1.4  29.5  180  20 10   8.3   4.6 |  -0.9  30.4  200  25 13   9.5   5.2
 13500  -0.2  31.6  175  18  9   8.4   4.6 |   0.5  32.9  195  24 12   9.6   5.2
 13000   1.0  33.8  170  16  8   9.0   5.0 |   1.9  35.4  195  22 11   9.2   5.0
 12500   2.3  36.1  165  16  8   9.1   5.0 |   3.3  37.9  195  20 10   9.1   5.0
 12000   3.7  38.7  165  15  8   9.3   5.1 |   4.6  40.3  195  18  9   8.9   4.9
 11500   5.1  41.2  165  14  7   9.3   5.1 |   5.9  42.6  195  15  8   8.8   4.8
 11000   6.4  43.5  165  14  7   9.1   5.0 |   7.2  45.0  195  12  6   7.5   4.1
 10500   7.8  46.0  165  13  7   8.6   4.7 |   8.2  46.8  200   9  5   6.3   3.4
 10250   8.5  47.3  165  13  7  11.7   6.4 |   8.6  47.5  200   8  4   9.3   5.1
 10000   9.4  48.9  165  13  7  12.0   6.6 |   9.4  48.9  210   6  3   9.8   5.4
  9750  10.2  50.4  165  13  7   9.4   5.2 |   9.9  49.8  225   5  2   7.0   3.9
  9500  10.9  51.6  165  12  6  10.3   5.7 |  10.5  50.9  250   4  2   7.8   4.3
  9250  11.7  53.1  165  12  6   9.2   5.1 |  11.0  51.8  280   4  2   7.4   4.1
  9000  12.3  54.1  165  12  6   9.2   5.0 |  11.5  52.7  305   5  3   7.3   4.0
  8750  13.1  55.6  165  12  6  10.2   5.6 |  12.1  53.8  315   6  3   7.4   4.1
  8500  13.8  56.8  165  11  6   9.5   5.2 |  12.6  54.7  320   8  4   7.1   3.9
  8250  14.6  58.3  165  11  6  11.2   6.2 |  13.1  55.6  325  10  5   8.3   4.6
  8000  15.4  59.7  165  11  6  11.1   6.1 |  13.8  56.8  325  12  6   9.4   5.1
  7750  16.2  61.2  165  11  5   9.0   4.9 |  14.4  57.9  325  13  7   8.6   4.7
  7500  16.8  62.2  165  10  5   8.7   4.8 |  15.0  59.0  325  14  7   8.1   4.5
  7250  17.5  63.5  165  10  5  10.2   5.6 |  15.6  60.1  330  15  8   9.2   5.0
  7000  18.3  64.9  165  10  5  11.5   6.3 |  16.4  61.5  330  16  8  10.1   5.6
  6750  19.2  66.6  165  10  5  10.0   5.5 |  17.1  62.8  330  16  8   9.1   5.0
  6500  19.9  67.8  165   9  5   9.6   5.3 |  17.8  64.0  330  17  9   8.9   4.9
  6250  20.6  69.1  165   9  5  10.5   5.7 |  18.5  65.3  330  17  9  10.4   5.7
  6000  21.4  70.5  165   9  4  11.3   6.2 |  19.3  66.7  330  17  9  11.6   6.4
  5750  22.3  72.1  165   8  4  10.2   5.6 |  20.1  68.2  330  17  9   9.7   5.3
  5500  23.1  73.6  165   8  4  15.4   8.5 |  20.8  69.4  330  16  8  11.1   6.1
________________________________________________________________________________

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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