Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 250028
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1828 MDT Sunday, April 24, 2016

This forecast is for Monday, April 25, 2016:

If the trigger temperature of 62.1 F/16.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1049 ft/min (5.3 m/s)
   Maximum height of thermals.................. 16930 ft MSL (11623 ft AGL)

Forecast maximum temperature................... 71.0 F/22.1 C
Time of trigger temperature.................... 1100 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................. 10949 ft MSL (5642 ft AGL)
Thermal soaring outlook for Tuesday 04/26...... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Getting worse.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 38558 ft MSL (33251 ft AGL)
Wave soaring outlook for Tuesday 04/26......... Poor

Remarks...

Sunrise/Sunset.................... 06:07:05 / 19:47:21 MDT
Total possible sunshine........... 13 hr 40 min 16 sec (820 min 16 sec)
Altitude of sun at 12:57:23 MDT... 63.75 degrees

Upper air data from numerical model forecast valid on 04/25/2016 at 0600 MDT

Freezing level.................. 11612 ft MSL (6305 ft AGL)
Convective condensation level... 15094 ft MSL (9787 ft AGL)
Lifted condensation level....... 15736 ft MSL (10429 ft AGL)
Lifted index.................... -1.5
K index......................... +17.9

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  -59.6 -75.3   240   33   17   2.2   1.2      M     M       M      M    M
 45000  -56.3 -69.3   245   48   25   1.1   0.6      M     M       M      M    M
 40000  -56.0 -68.8   240   68   35   0.2   0.1      M     M       M      M    M
 38000  -55.1 -67.2   240   73   37   3.1   1.7      M     M       M      M    M
 36000  -53.3 -63.9   240   74   38   3.1   1.7      M     M       M      M    M
 34000  -50.7 -59.3   235   75   38   6.8   3.7      M     M       M      M    M
 32000  -46.6 -51.9   235   69   36   6.7   3.7      M     M       M      M    M
 30000  -42.7 -44.9   235   63   32   5.9   3.3   33.0  91.4     8.5      M    M
 29000  -40.9 -41.6   235   58   30   6.0   3.3   31.4  88.5     7.4      M    M
 28000  -39.1 -38.4   235   53   27   6.0   3.3   29.9  85.9     6.4      M    M
 27000  -37.3 -35.1   235   48   24   6.7   3.7   28.6  83.5     5.4      M    M
 26000  -34.9 -30.8   235   46   24   8.5   4.7   28.0  82.3     4.9      M    M
 25000  -32.3 -26.1   240   45   23   8.5   4.7   27.5  81.5     4.6      M    M
 24000  -29.8 -21.6   240   43   22   8.5   4.7   27.1  80.8     4.3      M    M
 23000  -27.4 -17.3   245   43   22   8.0   4.4   26.5  79.6     3.8      M    M
 22000  -25.0 -13.0   245   43   22   8.1   4.4   25.8  78.5     3.3      M    M
 21000  -22.6  -8.7   245   43   22   8.1   4.5   25.3  77.6     2.9      M    M
 20000  -20.1  -4.2   245   38   20   8.3   4.5   24.7  76.5     2.4      M    M
 19500  -18.9  -2.0   245   36   18   8.3   4.6   24.4  76.0     2.2      M    M
 19000  -17.7   0.1   245   33   17   8.3   4.6   24.2  75.6     2.0      M    M
 18500  -16.4   2.5   245   31   16   8.1   4.4   24.0  75.2     1.8      M    M
 18000  -15.5   4.1   245   29   15   5.7   3.1   23.5  74.3     1.3      M    M
 17500  -14.6   5.7   245   27   14   5.9   3.2   22.8  73.1     0.7      M    M
 17000  -13.2   8.2   245   24   12   6.9   3.8   22.0  71.5    -0.0   1044  5.3
 16500  -12.2  10.0   240   22   11   6.8   3.7   21.5  70.6    -0.5    999  5.1
 16000  -11.1  12.0   240   20   10   8.2   4.5   21.1  69.9    -0.9    951  4.8
 15500   -9.8  14.4   235   18    9   8.2   4.5   20.8  69.4    -1.1    900  4.6
 15000   -8.6  16.5   230   16    8   8.5   4.7   20.6  69.0    -1.3    848  4.3
 14500   -7.3  18.9   235   15    8   8.7   4.8   20.4  68.7    -1.5    795  4.0
 14000   -6.0  21.2   235   13    7   8.9   4.9   20.2  68.4    -1.7    741  3.8
 13500   -4.6  23.7   240   13    7   9.3   5.1   20.1  68.2    -1.8    685  3.5
 13000   -3.2  26.2   245   13    7   9.1   5.0   20.1  68.1    -1.9    629  3.2
 12500   -2.0  28.4   250   13    7   7.9   4.3   19.8  67.7    -2.1    577  2.9
 12000   -0.8  30.6   255   14    7   8.0   4.4   19.5  67.2    -2.4    526  2.7
 11500    0.4  32.7   260   14    7   7.9   4.3   19.3  66.7    -2.7    476  2.4
 11000    1.5  34.7   260   16    8   7.8   4.3   19.0  66.1    -3.0    426  2.2
 10500    2.5  36.5   265   15    8   5.5   3.0   18.5  65.2    -3.5    382  1.9
 10250    2.9  37.2   265   15    8   6.3   3.4   18.2  64.7    -3.8    362  1.8
 10000    3.4  38.1   265   14    7   7.1   3.9   17.9  64.3    -4.0    340  1.7
  9750    3.9  39.0   265   13    6   6.6   3.6   17.7  63.9    -4.3    317  1.6
  9500    4.4  39.9   265   11    6   6.1   3.4   17.4  63.4    -4.6    295  1.5
  9250    4.9  40.8   260   10    5   6.2   3.4   17.1  62.9    -4.8    274  1.4
  9000    5.3  41.5   260    8    4   6.3   3.5   16.9  62.4    -5.1    253  1.3
  8750    5.8  42.4   255    7    4   6.2   3.4   16.6  61.9    -5.4    231  1.2
  8500    6.2  43.2   250    6    3   6.0   3.3   16.3  61.3    -5.7    211  1.1
  8250    6.7  44.1   235    5    3   5.7   3.1   16.0  60.8    -6.0    190  1.0
  8000    7.1  44.8   220    4    2   6.9   3.8   15.7  60.3    -6.3    170  0.9
  7750    7.7  45.9   200    4    2   7.2   3.9   15.6  60.0    -6.5    145  0.7
  7500    8.1  46.6   190    4    2   6.2   3.4   15.3  59.5    -6.8    124  0.6
  7250    8.6  47.5   180    5    2   6.5   3.6   15.0  59.1    -7.1    103  0.5
  7000    9.1  48.4   170    5    3   7.7   4.2   14.8  58.7    -7.3     81  0.4
  6750    9.7  49.5   170    5    3   7.4   4.0   14.7  58.4    -7.5     57  0.3
  6500   10.2  50.4   170    6    3   8.8   4.8   14.5  58.1    -7.7     34  0.2
  6250   10.7  51.3   170    7    3   1.6   0.9   14.3  57.8    -8.0     11  0.1
  6000   10.3  50.5   180    8    4  -6.4  -3.5   13.2  55.8    -9.1     14  0.1
  5750    9.6  49.3   190    9    5 -17.3  -9.5   11.8  53.2   -10.6     29  0.1
  5500    7.2  45.0   195    9    4 -41.1 -22.5    8.8  47.9   -13.7     92  0.5

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

           04/25/2016 at 0900 MDT          |       04/25/2016 at 1200 MDT
                                           |
K index... +12.5  LI... +2.5               | K index... +6.4  LI... -0.3
CAPE... 0.0  CIN... M                      | CAPE... +4.9  CIN... -29.0
                                           |
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 -58.1 -72.6  235  36 19   2.3   1.3 | -58.1 -72.6  230  37 19   1.8   1.0
 45000 -54.5 -66.1  245  56 29   0.6   0.3 | -55.3 -67.5  240  57 30   0.6   0.3
 40000 -58.1 -72.6  240  73 37  -2.5  -1.4 | -58.5 -73.3  235  72 37  -2.2  -1.2
 38000 -57.8 -72.0  240  75 39   4.4   2.4 | -58.2 -72.8  235  74 38   4.0   2.2
 36000 -55.2 -67.4  235  71 37   4.4   2.4 | -55.8 -68.4  235  70 36   4.0   2.2
 34000 -52.5 -62.5  235  67 35   6.7   3.7 | -53.3 -63.9  235  66 34   6.7   3.7
 32000 -47.8 -54.0  240  65 33   7.0   3.8 | -49.1 -56.4  235  62 32   6.9   3.8
 30000 -43.5 -46.3  245  62 32   7.9   4.4 | -44.3 -47.7  240  58 30   8.4   4.6
 29000 -41.1 -42.0  245  60 31   7.9   4.4 | -41.8 -43.2  240  58 30   8.4   4.6
 28000 -38.7 -37.7  245  57 29   7.9   4.4 | -39.2 -38.6  240  57 29   8.4   4.6
 27000 -36.3 -33.3  245  55 28   7.7   4.2 | -36.7 -34.1  240  56 29   8.6   4.7
 26000 -34.1 -29.4  245  52 27   7.2   3.9 | -34.1 -29.4  235  52 27   8.8   4.9
 25000 -32.0 -25.6  245  48 25   7.2   3.9 | -31.4 -24.5  230  48 25   8.8   4.9
 24000 -29.8 -21.6  245  45 23   7.2   3.9 | -28.8 -19.8  225  44 23   8.8   4.8
 23000 -27.7 -17.9  245  42 22   7.1   3.9 | -26.3 -15.3  225  43 22   8.0   4.4
 22000 -25.6 -14.1  245  40 21   7.2   3.9 | -23.9 -11.0  230  44 22   8.0   4.4
 21000 -23.5 -10.3  245  38 19   7.8   4.3 | -21.5  -6.7  235  44 23   7.2   4.0
 20000 -20.9  -5.6  240  33 17   8.8   4.8 | -19.7  -3.5  235  40 20   6.1   3.3
 19500 -19.6  -3.3  240  31 16   8.8   4.8 | -18.8  -1.8  235  37 19   6.1   3.3
 19000 -18.3  -0.9  240  28 15   8.8   4.8 | -17.9  -0.2  230  35 18   6.1   3.4
 18500 -17.0   1.4  235  26 13   8.8   4.8 | -16.9   1.6  230  33 17   6.3   3.5
 18000 -15.7   3.7  235  25 13   8.5   4.6 | -15.9   3.4  230  32 16   8.0   4.4
 17500 -14.5   5.9  235  23 12   8.5   4.7 | -14.7   5.5  230  31 16   7.9   4.3
 17000 -13.2   8.2  235  22 12   7.7   4.2 | -13.5   7.7  225  30 16   8.5   4.7
 16500 -11.5  11.3  235  22 11   7.7   4.2 | -12.2  10.0  230  30 16   8.6   4.7
 16000 -10.5  13.1  235  22 11   7.0   3.8 | -10.3  13.5  235  30 15   7.0   3.9
 15500  -9.4  15.1  235  22 12   7.0   3.8 |  -9.3  15.3  235  28 14   7.0   3.8
 15000  -8.4  16.9  235  23 12   7.3   4.0 |  -8.3  17.1  235  26 13   7.4   4.0
 14500  -7.3  18.9  235  23 12   7.4   4.1 |  -7.2  19.0  230  24 12   7.6   4.1
 14000  -6.2  20.8  235  23 12   7.6   4.1 |  -6.0  21.2  230  22 11   7.7   4.2
 13500  -5.1  22.8  235  21 11   7.7   4.2 |  -4.9  23.2  220  21 11   7.9   4.3
 13000  -3.9  25.0  235  19 10   7.7   4.3 |  -3.7  25.3  215  20 10   7.9   4.3
 12500  -2.8  27.0  235  17  9   7.8   4.3 |  -2.6  27.3  210  20 10   7.7   4.2
 12000  -1.6  29.1  230  15  8   7.9   4.3 |  -1.5  29.3  205  20 10   7.9   4.3
 11500  -0.4  31.3  225  13  7   8.6   4.7 |  -0.3  31.5  200  19 10   8.9   4.9
 11000   0.9  33.6  220  12  6   8.4   4.6 |   1.0  33.8  195  18  9   8.8   4.8
 10500   2.0  35.6  215  11  6   6.9   3.8 |   2.2  36.0  190  16  8   7.9   4.4
 10250   2.5  36.5  210  10  5   7.7   4.3 |   2.8  37.0  185  15  8   9.0   4.9
 10000   3.2  37.8  205  10  5   8.9   4.9 |   3.5  38.3  180  15  8  10.1   5.6
  9750   3.8  38.8  200  10  5   8.5   4.7 |   4.2  39.6  180  14  7   9.6   5.3
  9500   4.4  39.9  195  10  5   8.0   4.4 |   4.9  40.8  175  13  6   9.3   5.1
  9250   5.0  41.0  195  10  5   8.4   4.6 |   5.6  42.1  175  11  6   9.3   5.1
  9000   5.6  42.1  195   9  5   7.2   4.0 |   6.2  43.2  170  10  5   8.1   4.5
  8750   6.1  43.0  190   9  5   7.1   3.9 |   6.8  44.2  170  10  5   8.5   4.6
  8500   6.7  44.1  190   9  5   8.3   4.5 |   7.5  45.5  170  10  5   9.7   5.3
  8250   7.3  45.1  185   9  5   7.7   4.2 |   8.2  46.8  170   9  5   8.7   4.8
  8000   7.9  46.2  180   9  5   8.8   4.8 |   8.9  48.0  170   9  5  11.2   6.2
  7750   8.6  47.5  175   8  4   8.1   4.5 |   9.8  49.6  170   9  4  11.0   6.1
  7500   9.1  48.4  170   8  4   6.6   3.6 |  10.4  50.7  170   8  4   8.5   4.6
  7250   9.6  49.3  165   8  4   6.9   3.8 |  11.1  52.0  170   8  4   9.2   5.0
  7000  10.0  50.0  160   8  4   5.7   3.1 |  11.8  53.2  170   8  4   9.8   5.4
  6750  10.4  50.7  160   7  4   4.3   2.3 |  12.6  54.7  170   8  4  10.3   5.6
  6500  10.7  51.3  165   6  3   4.7   2.6 |  13.3  55.9  170   7  4   9.9   5.5
  6250  11.0  51.8  170   6  3   2.6   1.4 |  14.1  57.4  170   7  4  10.2   5.6
  6000  11.0  51.8  180   5  2  -0.6  -0.3 |  14.9  58.8  170   7  3  11.0   6.1
  5750  10.9  51.6  200   4  2   0.9   0.5 |  15.7  60.3  175   6  3   9.9   5.4
  5500  11.1  52.0  205   3  1   7.1   3.9 |  16.4  61.5  175   6  3  13.6   7.5

           04/25/2016 at 1500 MDT          |       04/25/2016 at 1800 MDT
                                           |
K index... +16.1  LI... +0.2               | K index... +11.5  LI... -0.9
CAPE... +4.9  CIN... -38.0                 | CAPE... +60.2  CIN... -16.6
                                           |
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 -57.3 -71.1  230  27 14   1.4   0.7 | -57.5 -71.5  235  22 11   1.4   0.8
 45000 -55.2 -67.4  240  31 16   0.3   0.1 | -55.3 -67.5  230  30 15   0.5   0.3
 40000 -58.4 -73.1  235  67 35  -2.2  -1.2 | -58.0 -72.4  230  65 33  -1.9  -1.0
 38000 -58.2 -72.8  230  76 39   4.0   2.2 | -57.8 -72.0  230  73 38   3.6   2.0
 36000 -55.8 -68.4  230  78 40   4.0   2.2 | -55.7 -68.3  230  74 38   3.6   2.0
 34000 -53.3 -63.9  230  79 40   6.2   3.4 | -53.4 -64.1  230  75 39   6.7   3.7
 32000 -49.4 -56.9  230  74 38   6.5   3.6 | -49.0 -56.2  225  71 36   7.4   4.1
 30000 -44.7 -48.5  225  70 36   8.8   4.8 | -43.9 -47.0  220  66 34   7.8   4.3
 29000 -42.0 -43.6  225  67 35   8.8   4.8 | -41.6 -42.9  220  65 34   7.8   4.3
 28000 -39.4 -38.9  225  65 34   8.8   4.8 | -39.3 -38.7  220  64 33   7.8   4.3
 27000 -36.8 -34.2  230  63 32   8.6   4.7 | -36.9 -34.4  220  63 33   7.9   4.3
 26000 -34.3 -29.7  225  61 31   8.1   4.4 | -34.5 -30.1  220  62 32   8.2   4.5
 25000 -31.9 -25.4  225  59 30   8.1   4.4 | -32.0 -25.6  225  61 31   8.2   4.5
 24000 -29.5 -21.1  225  57 29   8.1   4.4 | -29.6 -21.3  225  60 31   8.2   4.5
 23000 -26.8 -16.2  225  54 28   9.2   5.0 | -27.1 -16.8  225  59 30   8.6   4.7
 22000 -24.1 -11.4  225  51 26   9.2   5.0 | -24.5 -12.1  225  59 30   8.6   4.7
 21000 -21.3  -6.3  225  47 24   8.3   4.5 | -21.9  -7.4  225  58 30   8.1   4.4
 20000 -19.3  -2.7  230  45 23   6.8   3.7 | -19.9  -3.8  230  55 28   6.6   3.6
 19500 -18.3  -0.9  230  44 23   6.8   3.7 | -18.9  -2.0  230  53 27   6.6   3.6
 19000 -17.2   1.0  235  43 22   6.8   3.7 | -18.0  -0.4  230  51 26   6.6   3.6
 18500 -16.2   2.8  235  42 22   6.7   3.7 | -17.0   1.4  230  49 25   6.6   3.6
 18000 -15.3   4.5  235  40 20   5.8   3.2 | -15.9   3.4  230  47 24   8.4   4.6
 17500 -14.5   5.9  235  36 19   5.9   3.2 | -14.6   5.7  225  44 23   8.3   4.5
 17000 -13.5   7.7  235  33 17   7.1   3.9 | -13.4   7.9  225  41 21   8.7   4.8
 16500 -12.4   9.7  230  31 16   7.5   4.1 | -12.0  10.4  225  39 20   8.8   4.8
 16000 -10.7  12.7  220  27 14   8.5   4.7 | -10.1  13.8  220  37 19   8.6   4.7
 15500  -9.5  14.9  215  26 13   8.6   4.7 |  -8.8  16.2  215  36 18   8.6   4.7
 15000  -8.2  17.2  210  24 13   8.6   4.7 |  -7.5  18.5  210  35 18   8.8   4.8
 14500  -7.0  19.4  205  23 12   8.6   4.7 |  -6.2  20.8  205  33 17   8.9   4.9
 14000  -5.7  21.7  195  22 11   8.7   4.8 |  -4.9  23.2  205  32 17   9.0   4.9
 13500  -4.4  24.1  190  21 11   8.7   4.8 |  -3.6  25.5  200  31 16   9.2   5.0
 13000  -3.2  26.2  185  20 10   8.8   4.9 |  -2.3  27.9  195  30 16   9.2   5.1
 12500  -1.8  28.8  185  19 10   9.7   5.3 |  -0.9  30.4  195  30 15   9.5   5.2
 12000  -0.4  31.3  185  19 10   9.7   5.3 |   0.5  32.9  190  30 15   9.5   5.2
 11500   1.1  34.0  185  18 10   9.4   5.2 |   1.9  35.4  190  29 15   9.5   5.2
 11000   2.5  36.5  185  18  9   9.4   5.2 |   3.3  37.9  190  29 15   9.4   5.1
 10500   3.9  39.0  185  18  9   9.5   5.2 |   4.8  40.6  185  29 15  10.7   5.9
 10250   4.6  40.3  185  18  9  10.0   5.5 |   5.6  42.1  185  29 15   9.3   5.1
 10000   5.4  41.7  185  17  9  10.4   5.7 |   6.2  43.2  185  29 15   7.7   4.2
  9750   6.2  43.2  185  17  9  10.5   5.8 |   6.8  44.2  185  29 15   9.8   5.4
  9500   7.0  44.6  185  17  9  10.9   6.0 |   7.6  45.7  185  28 15  11.6   6.4
  9250   7.8  46.0  185  17  9  10.3   5.7 |   8.5  47.3  185  28 14  10.8   5.9
  9000   8.5  47.3  185  17  9   8.2   4.5 |   9.2  48.6  185  28 14   8.4   4.6
  8750   9.1  48.4  185  17  9   9.3   5.1 |   9.8  49.6  185  28 14   9.3   5.1
  8500   9.9  49.8  185  16  8  10.9   6.0 |  10.6  51.1  185  27 14  10.9   6.0
  8250  10.7  51.3  185  16  8  11.1   6.1 |  11.4  52.5  185  27 14  11.6   6.3
  8000  11.4  52.5  185  16  8   8.7   4.8 |  12.2  54.0  185  27 14   7.2   4.0
  7750  12.0  53.6  185  16  8   7.9   4.4 |  12.6  54.7  180  27 14   6.6   3.6
  7500  12.7  54.9  185  16  8  10.2   5.6 |  13.3  55.9  180  26 14  10.7   5.9
  7250  13.4  56.1  190  15  8   9.3   5.1 |  14.0  57.2  180  26 13   9.7   5.3
  7000  14.1  57.4  190  15  8  10.5   5.8 |  14.7  58.5  180  25 13   9.7   5.3
  6750  15.0  59.0  190  15  8  10.6   5.8 |  15.4  59.7  180  25 13   9.3   5.1
  6500  15.7  60.3  190  15  8   9.5   5.2 |  16.1  61.0  180  24 12   9.4   5.1
  6250  16.4  61.5  190  14  7  10.0   5.5 |  16.8  62.2  180  23 12   9.5   5.2
  6000  17.2  63.0  190  14  7  10.2   5.6 |  17.5  63.5  180  22 12   8.8   4.8
  5750  18.0  64.4  190  13  7  14.3   7.8 |  18.1  64.6  180  20 10   8.2   4.5
  5500  19.3  66.7  190  12  6  20.8  11.4 |  18.6  65.5  180  17  9   8.9   4.9
________________________________________________________________________________

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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