Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 290134
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1934 MDT Tuesday, July 28, 2015

This forecast is for Wednesday, July 29, 2015:

If the trigger temperature of 72.7 F/22.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 440 ft/min (2.2 m/s)
   Maximum height of thermals.................. 13837 ft MSL (8530 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1030 MDT
Time of overdevelopment........................ 1500 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................. 11670 ft MSL (6363 ft AGL)
Thermal soaring outlook for Thursday 07/30..... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 40936 ft MSL (35629 ft AGL)
Wave soaring outlook for Thursday 07/30........ Poor

Remarks...

Sunrise/Sunset.................... 05:55:34 / 20:16:36 MDT
Total possible sunshine........... 14 hr 21 min 2 sec (861 min 2 sec)
Altitude of sun at 13:05:53 MDT... 68.89 degrees

Upper air data from numerical model forecast valid on 07/29/2015 at 0600 MDT

Freezing level.................. 15758 ft MSL (10451 ft AGL)
Convective condensation level... 14773 ft MSL (9466 ft AGL)
Lifted condensation level....... 14319 ft MSL (9012 ft AGL)
Lifted index.................... -0.9
K index......................... +23.7

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  -65.7 -86.3   250   38   19   2.2   1.2      M     M       M      M    M
 45000  -60.8 -77.4   245   55   28   5.5   3.0      M     M       M      M    M
 40000  -51.6 -60.9   250   71   36   7.7   4.2      M     M       M      M    M
 38000  -47.0 -52.6   245   69   36   7.7   4.2      M     M       M      M    M
 36000  -42.3 -44.1   240   68   35   7.9   4.3      M     M       M      M    M
 34000  -37.4 -35.3   235   64   33   8.2   4.5      M     M       M      M    M
 32000  -32.5 -26.5   235   61   31   8.2   4.5      M     M       M      M    M
 30000  -27.8 -18.0   235   50   26   6.7   3.7   48.6 119.5    15.0      M    M
 29000  -25.8 -14.4   240   45   23   6.8   3.7   47.5 117.5    14.4      M    M
 28000  -23.7 -10.7   240   41   21   6.8   3.7   46.4 115.6    13.7      M    M
 27000  -21.7  -7.1   240   39   20   6.8   3.7   45.2 113.4    12.9      M    M
 26000  -19.7  -3.5   240   37   19   6.8   3.7   44.1 111.4    12.1      M    M
 25000  -17.7   0.1   245   34   18   6.1   3.3   43.1 109.6    11.5      M    M
 24000  -16.1   3.0   245   31   16   5.2   2.8   41.3 106.4    10.2      M    M
 23000  -14.5   5.9   250   27   14   5.2   2.8   39.7 103.4     8.9      M    M
 22000  -13.0   8.6   250   24   12   5.9   3.3   38.2 100.7     7.7      M    M
 21000  -11.1  12.0   250   24   13   6.7   3.7   36.9  98.5     6.7      M    M
 20000   -9.2  15.4   250   25   13   7.0   3.8   35.9  96.7     5.8      M    M
 19500   -8.2  17.2   245   25   13   7.2   4.0   35.5  95.9     5.3      M    M
 19000   -7.1  19.2   245   25   13   8.7   4.8   35.2  95.4     5.1      M    M
 18500   -5.8  21.6   250   25   13   8.6   4.7   35.0  95.0     4.9      M    M
 18000   -4.6  23.7   250   25   13   7.8   4.3   34.8  94.6     4.7      M    M
 17500   -3.6  25.5   250   23   12   7.4   4.0   34.3  93.8     4.2      M    M
 17000   -2.5  27.5   250   22   11   7.3   4.0   33.9  93.1     3.8      M    M
 16500   -1.6  29.1   250   20   11   6.1   3.4   33.4  92.1     3.4      M    M
 16000   -0.7  30.7   245   19   10   6.2   3.4   32.8  91.1     2.8      M    M
 15500    0.7  33.3   245   18    9   6.6   3.6   32.0  89.6     2.0      M    M
 15000    1.6  34.9   245   17    9   6.7   3.7   31.4  88.6     1.5      M    M
 14500    2.4  36.3   240   16    8   5.6   3.1   30.9  87.5     0.8      M    M
 14000    3.2  37.8   240   15    8   5.8   3.2   30.2  86.3     0.1      M    M
 13500    3.9  39.0   240   14    7   5.7   3.1   29.5  85.2    -0.6    608  3.1
 13000    4.7  40.5   235   13    7   5.6   3.1   28.9  84.0    -1.3    570  2.9
 12500    5.5  41.9   230   11    6   5.1   2.8   28.2  82.8    -1.9    531  2.7
 12000    6.3  43.3   225   10    5   4.9   2.7   27.4  81.3    -2.6    493  2.5
 11500    7.0  44.6   215    8    4   5.2   2.8   26.7  80.0    -3.3    455  2.3
 11000    7.8  46.0   205    9    5   5.2   2.9   25.9  78.7    -4.0    416  2.1
 10500    8.6  47.5   195   11    6   2.5   1.4   25.2  77.4    -4.7    379  1.9
 10250    8.7  47.7   195   11    6   3.1   1.7   24.6  76.2    -5.3    368  1.9
 10000    9.2  48.6   190   13    6   8.4   4.6   24.3  75.8    -5.6    347  1.8
  9750    9.8  49.6   190   14    7   8.8   4.8   24.2  75.6    -5.7    320  1.6
  9500   10.4  50.7   190   16    8   7.3   4.0   24.1  75.4    -5.8    295  1.5
  9250   10.9  51.6   190   16    8   5.8   3.2   23.9  75.6    -6.1    273  1.4
  9000   11.4  52.5   185   17    9   8.5   4.6   23.6  74.5    -6.4    251  1.3
  8750   12.1  53.8   185   18    9  10.0   5.5   23.6  74.5    -6.4    222  1.1
  8500   12.7  54.9   185   19   10   8.0   4.4   23.6  74.4    -6.5    195  1.0
  8250   13.3  55.9   185   19   10   7.3   4.0   23.4  74.1    -6.6    171  0.9
  8000   13.9  57.0   180   20   10   8.0   4.4   23.2  73.8    -6.8    146  0.7
  7750   14.5  58.1   180   21   11   8.3   4.5   23.1  73.6    -6.9    120  0.6
  7500   15.1  59.2   180   21   11   7.9   4.3   23.0  73.4    -7.1     95  0.5
  7250   15.7  60.3   180   21   11   7.4   4.1   22.8  73.1    -7.3     70  0.4
  7000   16.3  61.3   175   21   11   8.8   4.8   22.7  72.8    -7.4     45  0.2
  6750   16.9  62.4   175   22   11   5.8   3.2   22.6  72.7    -7.5     19  0.1
  6500   17.1  62.8   180   19   10   1.8   1.0   22.1  71.7    -8.1      6  0.0
  6250   17.3  63.1   180   17    9   3.7   2.0   21.5  70.7    -8.6      M    M
  6000   17.5  63.5   180   14    7   0.1   0.1   21.0  69.8    -9.2      M    M
  5750   17.1  62.8   185   10    5  -4.6  -2.5   20.1  68.1   -10.3      M    M
  5500   16.7  62.1   180    6    3  -2.7  -1.5   19.0  66.2   -11.5      M    M

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

           07/29/2015 at 0900 MDT          |       07/29/2015 at 1200 MDT
                                           |
K index... +19.2  LI... -0.7               | K index... +12.3  LI... -1.8
CAPE... +17.4  CIN... -26.2                | CAPE... +215.8  CIN... -42.1
                                           |
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 -65.0 -85.0  245  34 18   1.3   0.7 | -65.7 -86.3  235  37 19   1.0   0.6
 45000 -60.6 -77.1  245  52 27   5.5   3.0 | -61.1 -78.0  240  56 29   6.3   3.5
 40000 -51.8 -61.2  255  64 33   7.8   4.3 | -51.2 -60.2  255  63 32   7.9   4.3
 38000 -47.1 -52.8  250  61 32   7.7   4.2 | -46.5 -51.7  250  59 30   7.9   4.3
 36000 -42.5 -44.5  245  59 30   8.1   4.5 | -41.8 -43.2  245  56 29   8.0   4.4
 34000 -37.3 -35.1  235  58 30   8.8   4.8 | -36.9 -34.4  240  55 29   8.1   4.5
 32000 -32.0 -25.6  230  57 30   8.9   4.9 | -32.1 -25.8  240  55 28   9.0   4.9
 30000 -27.6 -17.7  235  49 25   6.2   3.4 | -27.0 -16.6  240  50 26   7.4   4.0
 29000 -25.8 -14.4  240  45 23   6.2   3.4 | -24.8 -12.6  245  47 24   7.4   4.0
 28000 -23.9 -11.0  245  41 21   6.5   3.6 | -22.8  -9.0  245  44 23   5.2   2.8
 27000 -21.9  -7.4  240  37 19   6.5   3.6 | -21.2  -6.2  245  40 21   5.4   2.9
 26000 -19.9  -3.8  240  34 17   6.5   3.6 | -19.5  -3.1  250  35 18   5.4   3.0
 25000 -18.0  -0.4  240  30 15   6.3   3.5 | -17.9  -0.2  250  31 16   5.8   3.2
 24000 -16.2   2.8  240  27 14   6.1   3.3 | -16.1   3.0  255  28 14   6.1   3.4
 23000 -14.3   6.3  245  24 12   6.1   3.3 | -14.2   6.4  255  25 13   6.1   3.4
 22000 -12.5   9.5  245  21 11   6.1   3.3 | -12.3   9.9  265  22 12   6.5   3.6
 21000 -10.8  12.6  245  21 11   6.1   3.4 | -10.4  13.3  265  21 11   6.7   3.7
 20000  -9.0  15.8  250  21 11   6.3   3.5 |  -8.4  16.9  265  20 11   6.7   3.7
 19500  -8.1  17.4  250  21 11   6.6   3.6 |  -7.4  18.7  265  20 10   6.7   3.7
 19000  -7.1  19.2  250  20 10   7.6   4.2 |  -6.4  20.5  265  20 10   6.6   3.6
 18500  -6.0  21.2  250  20 10   7.6   4.2 |  -5.4  22.3  265  20 10   6.6   3.6
 18000  -4.9  23.2  250  20 10   7.4   4.1 |  -4.4  24.1  265  20 10   6.3   3.5
 17500  -3.7  25.3  250  18  9   7.4   4.1 |  -3.5  25.7  265  19 10   6.2   3.4
 17000  -2.6  27.3  255  17  9   7.3   4.0 |  -2.6  27.3  270  18  9   6.2   3.4
 16500  -1.6  29.1  255  16  8   6.3   3.4 |  -1.2  29.8  275  17  9   6.5   3.5
 16000  -0.7  30.7  260  15  8   6.3   3.5 |  -0.3  31.5  280  16  8   6.8   3.7
 15500   0.7  33.3  260  13  7   7.2   4.0 |   0.8  33.4  280  15  8   7.5   4.1
 15000   1.7  35.1  260  12  6   7.5   4.1 |   1.8  35.2  285  14  7   7.6   4.2
 14500   2.7  36.9  260  12  6   7.2   3.9 |   2.9  37.2  290  13  7   7.8   4.3
 14000   3.7  38.7  255  11  6   7.3   4.0 |   4.0  39.2  290  12  6   7.9   4.3
 13500   4.6  40.3  250  10  5   6.7   3.7 |   5.1  41.2  295  11  6   7.8   4.3
 13000   5.5  41.9  245  10  5   6.7   3.7 |   6.2  43.2  290  10  5   8.0   4.4
 12500   6.5  43.7  240   9  5   6.7   3.7 |   7.3  45.1  290   9  5   6.8   3.8
 12000   7.4  45.3  235   9  4   6.7   3.7 |   8.1  46.6  280   8  4   6.6   3.6
 11500   8.3  46.9  230   8  4   5.8   3.2 |   9.0  48.2  270   7  4   6.6   3.6
 11000   9.1  48.4  225   7  4   5.3   2.9 |   9.9  49.8  260   6  3   6.6   3.6
 10500   9.8  49.6  220   7  4   2.9   1.6 |  10.7  51.3  245   6  3   3.4   1.9
 10250  10.0  50.0  220   7  4   3.4   1.9 |  10.9  51.6  240   5  3   4.2   2.3
 10000  10.4  50.7  220   7  4   7.0   3.9 |  11.4  52.5  230   5  3   8.0   4.4
  9750  10.9  51.6  215   7  4   7.1   3.9 |  11.9  53.4  220   5  2   7.3   4.0
  9500  11.4  52.5  210   7  4   6.1   3.3 |  12.3  54.1  205   5  2   5.9   3.3
  9250  11.8  53.2  205   9  4   5.1   2.8 |  12.7  54.9  185   5  3   5.1   2.8
  9000  12.2  54.0  200  10  5   7.1   3.9 |  13.1  55.6  175   6  3   8.0   4.4
  8750  12.8  55.0  195  12  6   7.9   4.3 |  13.7  56.7  165   7  4   9.7   5.3
  8500  13.3  55.9  190  14  7   5.9   3.2 |  14.3  57.7  160   8  4   8.9   4.9
  8250  13.7  56.7  190  16  8   5.1   2.8 |  15.0  59.0  160   8  4   8.5   4.7
  8000  14.1  57.4  190  18  9   6.1   3.3 |  15.6  60.1  160   8  4   9.8   5.4
  7750  14.6  58.3  185  20 10   6.4   3.5 |  16.4  61.5  155   8  4  10.8   5.9
  7500  15.0  59.0  185  20 10   5.5   3.0 |  17.1  62.8  155   8  4  10.1   5.5
  7250  15.4  59.7  185  20 10   5.5   3.0 |  17.9  64.2  155   8  4   9.9   5.4
  7000  15.8  60.4  180  19 10   5.0   2.8 |  18.6  65.5  155   8  4  10.6   5.8
  6750  16.2  61.2  180  19 10   7.2   3.9 |  19.4  66.9  155   8  4  10.8   5.9
  6500  16.8  62.2  180  16  8   9.3   5.1 |  20.2  68.4  155   8  4  10.4   5.7
  6250  17.4  63.3  175  14  7   8.6   4.7 |  21.0  69.8  155   8  4  10.4   5.7
  6000  18.0  64.4  175  12  6   9.3   5.1 |  21.8  71.2  155   8  4  10.8   5.9
  5750  18.9  66.0  175  10  5  13.6   7.5 |  22.7  72.9  155   7  4  17.3   9.5
  5500  20.1  68.2  170   9  5  19.1  10.5 |  24.4  75.9  155   7  4  26.6  14.6

           07/29/2015 at 1500 MDT          |       07/29/2015 at 1800 MDT
                                           |
K index... +25.4  LI... -3.1               | K index... +29.7  LI... -3.9
CAPE... +500.5  CIN... -4.3                | CAPE... +497.4  CIN... -4.1
                                           |
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 -66.8 -88.2  235  40 20   0.8   0.5 | -66.9 -88.4  240  37 19   1.1   0.6
 45000 -61.8 -79.2  240  56 29   7.4   4.1 | -61.7 -79.1  240  51 26   7.3   4.0
 40000 -50.5 -58.9  255  60 31   7.9   4.3 | -50.5 -58.9  245  53 27   8.5   4.7
 38000 -45.8 -50.4  250  58 30   7.9   4.3 | -45.4 -49.7  245  54 28   8.5   4.7
 36000 -41.1 -42.0  245  58 30   7.9   4.3 | -40.3 -40.5  245  55 28   8.1   4.5
 34000 -36.4 -33.5  245  56 29   7.9   4.3 | -35.6 -32.1  245  55 28   7.8   4.3
 32000 -31.1 -24.0  240  54 28   8.1   4.4 | -30.3 -22.5  245  55 28   7.6   4.2
 30000 -26.9 -16.4  245  48 25   6.9   3.8 | -26.3 -15.3  250  48 25   6.7   3.7
 29000 -24.8 -12.6  245  45 23   6.9   3.8 | -24.3 -11.7  255  44 23   6.7   3.7
 28000 -22.8  -9.0  250  43 22   6.1   3.3 | -22.4  -8.3  260  42 21   6.3   3.5
 27000 -20.9  -5.6  250  40 21   6.2   3.4 | -20.5  -4.9  260  40 21   6.4   3.5
 26000 -19.1  -2.4  255  37 19   6.2   3.4 | -18.6  -1.5  265  38 20   6.4   3.5
 25000 -17.2   1.0  255  35 18   6.0   3.3 | -16.6   2.1  265  37 19   5.9   3.2
 24000 -15.4   4.3  260  31 16   5.9   3.3 | -15.0   5.0  275  34 17   5.5   3.0
 23000 -13.6   7.5  265  27 14   5.9   3.3 | -13.3   8.1  280  31 16   5.5   3.0
 22000 -11.9  10.6  270  24 12   6.3   3.5 | -11.6  11.1  285  29 15   5.5   3.0
 21000  -9.9  14.2  275  23 12   6.5   3.6 | -10.0  14.0  290  28 15   5.5   3.0
 20000  -8.0  17.6  280  23 12   6.6   3.6 |  -8.4  16.9  290  28 14   5.6   3.1
 19500  -7.0  19.4  280  22 12   6.7   3.6 |  -7.6  18.3  290  28 14   5.7   3.1
 19000  -6.0  21.2  280  23 12   7.1   3.9 |  -6.6  20.1  295  28 14   7.4   4.0
 18500  -5.0  23.0  285  23 12   7.1   3.9 |  -5.5  22.1  295  28 14   7.3   4.0
 18000  -3.9  25.0  285  24 12   6.3   3.5 |  -4.5  23.9  295  28 15   6.9   3.8
 17500  -3.1  26.4  285  25 13   6.1   3.3 |  -3.6  25.5  295  27 14   6.8   3.7
 17000  -2.2  28.0  285  26 13   6.2   3.4 |  -2.1  28.2  300  26 13   6.8   3.8
 16500  -0.9  30.4  285  25 13   6.6   3.6 |  -1.2  29.8  300  22 12   6.9   3.8
 16000   0.0  32.0  290  24 13   6.8   3.7 |  -0.2  31.6  305  19 10   6.7   3.7
 15500   1.0  33.8  290  22 11   7.1   3.9 |   0.6  33.1  300  15  8   5.9   3.2
 15000   1.9  35.4  290  20 10   7.3   4.0 |   1.3  34.3  300  10  5   6.0   3.3
 14500   2.9  37.2  295  17  9   7.2   4.0 |   2.2  36.0  285   6  3   7.0   3.8
 14000   4.0  39.2  300  14  7   7.2   4.0 |   3.1  37.6  235   3  2   6.9   3.8
 13500   5.1  41.2  300  11  6   7.4   4.0 |   4.1  39.4  185   5  2   8.4   4.6
 13000   6.2  43.2  305   8  4   7.4   4.1 |   5.2  41.4  175   6  3   8.6   4.7
 12500   7.2  45.0  310   6  3   7.1   3.9 |   6.4  43.5  165   7  4   8.9   4.9
 12000   8.2  46.8  295   2  1   7.1   3.9 |   7.7  45.9  160   8  4   9.0   4.9
 11500   9.1  48.4  160   2  1   7.6   4.2 |   9.0  48.2  150   8  4   9.7   5.3
 11000  10.1  50.2  145   5  3   8.0   4.4 |  10.5  50.9  150   8  4  10.0   5.5
 10500  10.9  51.6  140   8  4   3.1   1.7 |  11.8  53.2  150   8  4   3.7   2.1
 10250  11.1  52.0  140   8  4   7.4   4.0 |  12.0  53.6  150   8  4   7.0   3.8
 10000  12.1  53.8  140   8  4  14.9   8.2 |  13.0  55.4  150   8  4  14.5   7.9
  9750  13.0  55.4  140   8  4  12.5   6.9 |  13.9  57.0  150   8  4  12.3   6.7
  9500  13.8  56.8  140   8  4   9.2   5.1 |  14.8  58.6  150   8  4   9.7   5.3
  9250  14.4  57.9  140   8  4   7.4   4.0 |  15.4  59.7  150   8  4   8.1   4.4
  9000  15.1  59.2  140   8  4  10.8   5.9 |  16.1  61.0  145   8  4  10.9   6.0
  8750  16.0  60.8  140   8  4  11.7   6.4 |  17.0  62.6  145   7  4  11.5   6.3
  8500  16.8  62.2  140   8  4  10.2   5.6 |  17.8  64.0  145   7  4  10.2   5.6
  8250  17.5  63.5  140   8  4   9.8   5.4 |  18.5  65.3  145   7  4   9.7   5.3
  8000  18.2  64.8  135   8  4   9.9   5.4 |  19.2  66.6  145   7  4  10.0   5.5
  7750  19.0  66.2  135   8  4  10.0   5.5 |  20.0  68.0  145   7  4  10.0   5.5
  7500  19.7  67.5  135   7  4  10.1   5.6 |  20.7  69.3  145   7  4   9.8   5.4
  7250  20.5  68.9  135   7  4  10.2   5.6 |  21.5  70.7  140   7  4   9.6   5.3
  7000  21.2  70.2  135   7  4   9.9   5.4 |  22.2  72.0  140   7  4  10.3   5.7
  6750  22.0  71.6  135   7  4  10.2   5.6 |  23.0  73.4  140   7  3  10.2   5.6
  6500  22.8  73.0  135   7  4  10.8   5.9 |  23.7  74.7  140   7  3   9.5   5.2
  6250  23.5  74.3  135   7  4  10.7   5.9 |  24.4  75.9  140   7  3   9.4   5.1
  6000  24.3  75.7  135   7  4  10.5   5.7 |  25.1  77.2  140   6  3  10.5   5.8
  5750  25.3  77.5  135   7  3  16.8   9.2 |  26.0  78.8  140   6  3  14.4   7.9
  5500  27.0  80.6  135   7  3  28.1  15.4 |  27.2  81.0  140   6  3  17.1   9.4
________________________________________________________________________________

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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