Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0713 MDT Wednesday, July 19, 2017

This forecast is for Wednesday, July 19, 2017:

If the trigger temperature of 89.4 F/31.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1001 ft/min (5.1 m/s)
   Maximum height of thermals.................. 16202 ft MSL (10917 ft AGL)

Forecast maximum temperature................... 96.0 F/36.0 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10213 ft MSL (4928 ft AGL)
Thermal soaring outlook for Thursday 07/20..... 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)................ Neither
Potential height of wave....................... 14377 ft MSL (9092 ft AGL)
Wave soaring outlook for Thursday 07/20........ Poor

Remarks...

Sunrise/Sunset.................... 05:47:28 / 20:24:20 MDT
Total possible sunshine........... 14 hr 36 min 52 sec (876 min 52 sec)
Altitude of sun at 13:05:47 MDT... 70.90 degrees

Upper air data from rawinsonde observation taken on 07/19/2017 at 0600 MDT

Freezing level.................. 17320 ft MSL (12035 ft AGL)
Convective condensation level... 17467 ft MSL (12182 ft AGL)
Lifted condensation level....... 17343 ft MSL (12058 ft AGL)
Lifted index.................... -0.7
K index......................... +21.3

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -68.5 -91.3   225   32   16   4.9   2.7   76.8 170.3    24.1      M    M
 45000  -61.8 -79.2   260   14    7   3.6   2.0   63.8 146.8    17.7      M    M
 40000  -50.5 -58.9   265   19   10   7.8   4.3   57.3 135.1    14.7      M    M
 38000  -46.0 -50.8   250   21   11   7.1   3.9   55.5 131.9    13.8      M    M
 36000  -41.7 -43.1   235   25   13   7.6   4.2   53.4 128.0    12.6      M    M
 34000  -37.1 -34.8   235   21   11   7.7   4.2   51.6 124.9    11.6      M    M
 32000  -32.1 -25.8   230   16    8   7.9   4.3   50.4 122.8    11.0      M    M
 30000  -28.6 -19.5   175    7    4   5.8   3.2   47.4 117.2     8.9      M    M
 29000  -26.3 -15.3   120    2    1   9.0   4.9   46.6 115.8     8.4      M    M
 28000  -22.9  -9.2   090    1    0   8.9   4.9   46.3 115.3     8.4      M    M
 27000  -20.3  -4.5   325    3    1   8.7   4.7   45.9 114.5     8.2      M    M
 26000  -17.6   0.3   355    9    5   8.8   4.8   45.4 113.8     7.9      M    M
 25000  -15.4   4.3   325    6    3   7.4   4.1   44.7 112.4     7.3      M    M
 24000  -13.0   8.6   215    7    4   8.1   4.5   44.1 111.4     6.9      M    M
 23000  -11.0  12.2   205    7    4   7.4   4.0   43.1 109.6     6.1      M    M
 22000  -10.3  13.5   200    7    4   3.7   2.0   40.6 105.1     3.9      M    M
 21000   -8.2  17.2   245    8    4   9.3   5.1   39.5 103.1     3.1      M    M
 20000   -5.8  21.6   235    7    4   8.2   4.5   39.0 102.2     2.7      M    M
 19500   -4.7  23.5   210    6    3   7.4   4.1   38.7 101.6     2.3      M    M
 19000   -3.7  25.3   185    7    4   7.0   3.8   38.2 100.7     1.8      M    M
 18500   -2.7  27.1   185    7    4   7.0   3.8   37.7  99.8     1.3      M    M
 18000   -1.7  28.9   185    7    4   6.9   3.8   37.2  99.0     0.9      M    M
 17500   -0.6  30.9   170    8    4   8.5   4.7   36.9  98.4     0.5      M    M
 17000    0.6  33.1   160    9    4   8.3   4.6   36.7  98.0     0.3      M    M
 16500    1.8  35.2   150   10    5   8.3   4.6   36.5  97.6     0.1      M    M
 16000    3.1  37.6   140   12    6   8.3   4.6   36.3  97.3    -0.0    990  5.0
 15500    4.3  39.7   140    9    5   8.4   4.6   36.1  97.0    -0.2    939  4.8
 15000    5.5  41.9   150    6    3   8.4   4.6   35.9  96.6    -0.5    887  4.5
 14500    7.3  45.1   195    4    2   8.4   4.6   35.6  96.0    -0.8    810  4.1
 14000    8.6  47.5   225    6    3   8.4   4.6   35.3  95.6    -1.0    758  3.9
 13500    9.8  49.6   235    8    4   8.4   4.6   35.1  95.1    -1.3    707  3.6
 13000   11.0  51.8   240   11    6   8.4   4.6   34.8  94.7    -1.6    655  3.3
 12500   12.2  54.0   245   14    7   8.4   4.6   34.6  94.3    -1.8    604  3.1
 12000   13.5  56.3   245   17    9   8.4   4.6   34.4  93.9    -2.0    552  2.8
 11500   14.7  58.5   250   18    9   8.4   4.6   34.1  93.4    -2.3    501  2.5
 11000   15.9  60.6   250   19   10   8.4   4.6   33.9  93.0    -2.6    449  2.3
 10500   17.1  62.8   245   20   10   8.2   4.5   33.6  92.5    -2.9    398  2.0
 10250   17.7  63.9   245   20   10   8.1   4.4   33.5  92.3    -3.0    373  1.9
 10000   18.3  64.9   245   20   10   8.1   4.5   33.4  92.1    -3.2    347  1.8
  9750   18.9  66.0   240   20   10   8.1   4.4   33.2  91.8    -3.3    322  1.6
  9500   19.5  67.1   240   20   10   8.1   4.4   33.1  91.6    -3.4    297  1.5
  9250   20.1  68.2   240   20   10   8.2   4.5   33.0  91.4    -3.5    272  1.4
  9000   20.7  69.3   240   20   10   8.0   4.4   32.9  91.2    -3.7    246  1.3
  8750   21.3  70.3   240   20   10   8.7   4.8   32.8  91.0    -3.8    221  1.1
  8500   21.9  71.4   235   19   10   5.9   3.2   32.6  90.7    -4.0    196  1.0
  8250   22.1  71.8   235   19   10   2.4   1.3   32.1  89.9    -4.5    181  0.9
  8000   22.3  72.1   235   19   10   2.7   1.5   31.6  88.9    -5.0    169  0.9
  7750   22.5  72.5   235   18    9   2.7   1.5   31.1  87.9    -5.6    157  0.8
  7500   22.6  72.7   230   18    9   2.7   1.5   30.5  86.9    -6.2    144  0.7
  7250   22.8  73.0   230   17    9   2.7   1.5   30.0  86.0    -6.8    132  0.7
  7000   23.0  73.4   225   17    9   2.7   1.5   29.4  85.0    -7.3    119  0.6
  6750   23.2  73.8   225   18    9   2.6   1.4   28.9  84.0    -7.9    107  0.5
  6500   23.3  73.9   225   18   10   3.0   1.7   28.4  83.1    -8.5     94  0.5
  6250   23.5  74.3   225   19   10   1.6   0.9   27.8  82.1    -9.1     82  0.4
  6000   23.3  73.9   225   20   10  -5.5  -3.0   27.0  80.6   -10.0     80  0.4
  5750   22.5  72.5   220   15    8 -10.0  -5.5   25.6  78.1   -11.5     96  0.5
  5500   21.8  71.2   205   10    5  -6.5  -3.6   24.2  75.6   -13.0    112  0.6

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

           07/19/2017 at 0900 MDT          |       07/19/2017 at 1200 MDT
                                           |
K index... +26.3  LI... -2.2               | K index... +26.4  LI... -2.5
CAPE... +515.2  CIN... -96.3               | CAPE... +845.7  CIN... -52.1
                                           |
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 -66.1 -87.0  235  26 13   1.7   0.9 | -66.7 -88.1  245  27 14   1.8   1.0
 45000 -61.0 -77.8  230  26 13   6.2   3.4 | -61.1 -78.0  240  27 14   7.0   3.8
 40000 -50.8 -59.4  260  16  8   7.7   4.2 | -50.0 -58.0  235  15  8   7.4   4.1
 38000 -46.1 -51.0  265  20 10   7.7   4.2 | -45.5 -49.9  255  16  8   7.4   4.1
 36000 -41.5 -42.7  260  24 12   8.1   4.5 | -41.0 -41.8  270  18  9   8.1   4.5
 34000 -36.6 -33.9  255  19 10   8.1   4.4 | -36.2 -33.2  260  17  9   8.1   4.4
 32000 -31.8 -25.2  240  15  8   8.4   4.6 | -31.3 -24.3  250  17  9   8.4   4.6
 30000 -27.5 -17.5  210  11  6   7.2   3.9 | -26.4 -15.5  225  16  8   7.3   4.0
 29000 -24.8 -12.6  180  11  5   7.2   3.9 | -24.2 -11.6  210  16  8   7.3   4.0
 28000 -22.5  -8.5  170  11  5   8.1   4.5 | -22.0  -7.6  205  16  8   7.5   4.1
 27000 -20.1  -4.2  170  10  5   8.2   4.5 | -19.8  -3.6  205  16  8   7.5   4.1
 26000 -17.7   0.1  170   8  4   8.2   4.5 | -17.6   0.3  205  16  8   7.6   4.2
 25000 -15.4   4.3  170   8  4   6.4   3.5 | -15.4   4.3  205  15  8   6.8   3.7
 24000 -13.4   7.9  185   7  4   6.7   3.7 | -13.3   8.1  210  14  7   6.9   3.8
 23000 -11.5  11.3  195   7  4   6.7   3.7 | -11.3  11.7  215  13  7   6.9   3.8
 22000  -9.6  14.7  205   8  4   6.3   3.4 |  -9.3  15.3  225  12  6   7.3   4.0
 21000  -7.8  18.0  200  10  5   6.4   3.5 |  -7.2  19.0  225  12  6   7.2   4.0
 20000  -6.0  21.2  195  12  6   6.5   3.6 |  -5.0  23.0  230  12  6   7.3   4.0
 19500  -5.1  22.8  195  13  7   7.3   4.0 |  -4.0  24.8  230  12  6   6.9   3.8
 19000  -3.9  25.0  195  14  7   8.0   4.4 |  -3.0  26.6  230  12  6   6.5   3.6
 18500  -2.7  27.1  195  14  7   8.1   4.4 |  -2.0  28.4  230  12  6   6.4   3.5
 18000  -1.6  29.1  195  15  8   7.5   4.1 |  -1.0  30.2  230  11  6   7.8   4.3
 17500  -0.4  31.3  195  15  8   7.6   4.1 |   0.1  32.2  225  11  6   7.7   4.2
 17000   0.7  33.3  195  15  8   7.6   4.2 |   1.2  34.2  225  11  6   7.8   4.3
 16500   1.8  35.2  195  15  8   7.7   4.2 |   2.4  36.3  230  11  6   7.9   4.4
 16000   3.0  37.4  200  15  8   7.6   4.2 |   3.5  38.3  230  12  6   8.0   4.4
 15500   4.1  39.4  200  14  7   8.6   4.7 |   5.2  41.4  235  12  6   8.1   4.4
 15000   6.0  42.8  200  14  7   8.5   4.6 |   6.3  43.3  235  12  6   8.1   4.5
 14500   7.2  45.0  200  13  7   8.3   4.6 |   7.5  45.5  235  12  6   8.5   4.7
 14000   8.4  47.1  200  12  6   8.4   4.6 |   8.7  47.7  230  12  6   8.6   4.7
 13500   9.6  49.3  195  12  6   8.1   4.4 |   9.8  49.6  225  11  6   7.7   4.2
 13000  10.8  51.4  195  11  6   8.1   4.4 |  10.9  51.6  220  11  5   7.7   4.2
 12500  11.9  53.4  195  11  5   8.4   4.6 |  12.0  53.6  215  10  5   7.7   4.2
 12000  13.1  55.6  200  10  5   8.5   4.6 |  13.1  55.6  205  10  5   7.6   4.2
 11500  14.3  57.7  200   9  5   8.4   4.6 |  14.3  57.7  200   9  5   8.1   4.5
 11000  15.5  59.9  205   8  4   8.5   4.7 |  15.5  59.9  200   8  4   8.4   4.6
 10500  16.5  61.7  210   7  4   3.2   1.8 |  16.6  61.9  195   7  4   5.1   2.8
 10250  16.8  62.2  215   7  3   6.6   3.6 |  17.0  62.6  195   7  3   7.6   4.2
 10000  17.5  63.5  215   6  3  11.9   6.5 |  17.7  63.9  190   6  3  10.9   6.0
  9750  18.3  64.9  220   6  3  10.4   5.7 |  18.4  65.1  190   5  3  10.1   5.5
  9500  18.9  66.0  225   6  3   7.2   3.9 |  19.1  66.4  190   4  2   8.5   4.7
  9250  19.3  66.7  225   6  3   5.6   3.0 |  19.7  67.5  190   4  2   7.7   4.2
  9000  19.8  67.6  225   6  3   8.2   4.5 |  20.3  68.5  195   3  2   8.9   4.9
  8750  20.5  68.9  225   6  3   8.5   4.7 |  20.9  69.6  200   3  2   8.9   4.9
  8500  21.0  69.8  220   7  3   7.5   4.1 |  21.6  70.9  200   3  1   9.2   5.1
  8250  21.5  70.7  220   7  4   7.1   3.9 |  22.2  72.0  205   3  1   9.2   5.1
  8000  22.1  71.8  215   7  4   7.1   3.9 |  22.9  73.2  205   2  1  10.0   5.5
  7750  22.5  72.5  215   8  4   6.1   3.4 |  23.7  74.7  210   2  1  10.6   5.8
  7500  22.9  73.2  215   8  4   4.5   2.5 |  24.4  75.9  210   2  1  10.2   5.6
  7250  23.2  73.8  215   8  4   3.8   2.1 |  25.2  77.4  210   2  1  10.1   5.6
  7000  23.5  74.3  215   8  4   4.8   2.6 |  25.9  78.6  215   2  1  10.0   5.5
  6750  23.8  74.8  215   9  5   4.3   2.4 |  26.7  80.1  220   2  1  10.4   5.7
  6500  24.1  75.4  215   8  4   2.8   1.5 |  27.5  81.5  220   2  1  10.8   5.9
  6250  24.2  75.6  215   6  3   2.5   1.4 |  28.3  82.9  225   2  1  11.2   6.1
  6000  24.4  75.9  215   5  2   3.6   2.0 |  29.1  84.4  225   2  1   9.9   5.4
  5750  24.9  76.8  215   4  2  11.6   6.4 |  29.9  85.8  230   2  1  16.3   9.0
  5500  26.1  79.0  220   3  2  21.2  11.6 |  31.7  89.1  230   2  1  30.4  16.7

           07/19/2017 at 1500 MDT          |       07/19/2017 at 1800 MDT
                                           |
K index... +27.9  LI... -2.2               | K index... +35.9  LI... -2.7
CAPE... +733.4  CIN... -22.3               | CAPE... +670.5  CIN... -57.9
                                           |
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 -67.3 -89.1  250  25 13   1.3   0.7 | -68.1 -90.6  270  20 10   0.6   0.3
 45000 -61.2 -78.2  255  27 14   7.5   4.1 | -61.9 -79.4  280  22 11   8.7   4.8
 40000 -49.8 -57.6  250  24 12   8.1   4.4 | -48.9 -56.0  280  22 11   8.3   4.6
 38000 -45.0 -49.0  260  23 12   8.1   4.4 | -43.9 -47.0  270  24 13   8.3   4.6
 36000 -40.1 -40.2  270  24 12   7.7   4.2 | -39.1 -38.4  265  26 13   6.6   3.6
 34000 -35.5 -31.9  265  19 10   7.8   4.3 | -35.1 -31.2  245  21 11   6.7   3.7
 32000 -30.8 -23.4  260  14  7   8.4   4.6 | -31.1 -24.0  215  20 10   8.1   4.5
 30000 -25.6 -14.1  230  14  7   7.7   4.3 | -25.7 -14.3  210  23 12   8.0   4.4
 29000 -23.3  -9.9  215  16  8   7.7   4.2 | -23.3  -9.9  205  24 13   7.9   4.4
 28000 -21.1  -6.0  210  17  9   6.9   3.8 | -21.0  -5.8  205  25 13   7.1   3.9
 27000 -19.1  -2.4  210  17  9   6.9   3.8 | -19.0  -2.2  205  24 12   7.1   3.9
 26000 -17.0   1.4  210  17  9   6.9   3.8 | -16.9   1.6  210  24 12   7.1   3.9
 25000 -15.0   5.0  215  17  9   7.1   3.9 | -14.9   5.2  210  23 12   6.8   3.7
 24000 -12.9   8.8  215  15  8   7.2   3.9 | -12.8   9.0  205  23 12   6.8   3.7
 23000 -10.8  12.6  220  13  7   7.3   4.0 | -10.8  12.6  205  22 11   6.8   3.7
 22000  -8.8  16.2  220  12  6   6.7   3.7 |  -8.9  16.0  200  21 11   6.6   3.6
 21000  -6.8  19.8  220  12  6   6.7   3.7 |  -7.0  19.4  195  20 10   6.6   3.6
 20000  -4.8  23.4  215  11  6   6.7   3.7 |  -5.1  22.8  185  18  9   6.7   3.7
 19500  -3.8  25.2  210  11  6   6.9   3.8 |  -4.2  24.4  185  17  9   6.7   3.6
 19000  -2.8  27.0  210  11  6   7.1   3.9 |  -3.3  26.1  180  17  9   6.4   3.5
 18500  -1.7  28.9  205  11  5   7.1   3.9 |  -2.4  27.7  175  16  8   6.4   3.5
 18000  -0.6  30.9  205  10  5   7.7   4.2 |  -1.5  29.3  170  16  8   6.0   3.3
 17500   0.5  32.9  205  10  5   7.7   4.2 |  -0.7  30.7  170  15  8   6.0   3.3
 17000   1.6  34.9  200   9  5   7.8   4.3 |   0.2  32.4  165  15  8   6.3   3.4
 16500   2.7  36.9  200   9  5   8.1   4.4 |   1.1  34.0  160  15  7   7.3   4.0
 16000   3.9  39.0  200   8  4   8.1   4.5 |   2.6  36.7  160  14  7   8.1   4.5
 15500   5.6  42.1  195   8  4   7.7   4.2 |   3.9  39.0  155  13  7   9.3   5.1
 15000   6.6  43.9  190   9  4   7.8   4.3 |   5.2  41.4  155  13  6   9.4   5.1
 14500   7.8  46.0  185   9  5   8.0   4.4 |   6.6  43.9  155  12  6   9.6   5.3
 14000   8.9  48.0  185  10  5   7.9   4.3 |   8.0  46.4  155  12  6   9.6   5.3
 13500  10.1  50.2  180  10  5   8.7   4.7 |   9.5  49.1  160  12  6   9.8   5.4
 13000  11.3  52.3  180  10  5   8.7   4.7 |  10.9  51.6  160  11  6   9.8   5.4
 12500  12.5  54.5  180   9  5   9.0   4.9 |  12.4  54.3  160  11  6   9.8   5.4
 12000  13.8  56.8  185   9  4   9.1   5.0 |  13.9  57.0  160  10  5   9.8   5.4
 11500  15.1  59.2  185   8  4   9.2   5.1 |  15.3  59.5  160  10  5   9.3   5.1
 11000  16.4  61.5  190   8  4   9.3   5.1 |  16.6  61.9  165   8  4   8.7   4.8
 10500  17.7  63.9  190   8  4   5.3   2.9 |  18.0  64.4  170   6  3   3.9   2.2
 10250  18.1  64.6  190   7  4   7.8   4.3 |  18.1  64.6  170   5  3   4.5   2.4
 10000  18.9  66.0  190   7  4  12.8   7.0 |  18.8  65.8  185   4  2  11.0   6.0
  9750  19.8  67.6  195   7  4  12.1   6.7 |  19.5  67.1  210   2  1  10.0   5.5
  9500  20.7  69.3  195   7  4   9.3   5.1 |  20.3  68.5  260   2  1   7.5   4.1
  9250  21.2  70.2  195   7  4   8.3   4.5 |  20.7  69.3  285   4  2   4.6   2.5
  9000  22.0  71.6  195   7  4  11.3   6.2 |  21.1  70.0  295   5  3   5.7   3.1
  8750  22.8  73.0  200   7  4  11.0   6.1 |  21.5  70.7  300   8  4   6.0   3.3
  8500  23.6  74.5  200   7  4  10.6   5.8 |  21.9  71.4  305  10  5   4.6   2.5
  8250  24.4  75.9  200   7  4  10.2   5.6 |  22.1  71.8  305  13  7   3.5   1.9
  8000  25.1  77.2  200   7  4   9.8   5.4 |  22.3  72.1  305  16  8   2.9   1.6
  7750  25.8  78.4  205   7  4   9.4   5.2 |  22.4  72.3  300  19 10   1.8   1.0
  7500  26.6  79.9  205   7  4  10.2   5.6 |  22.6  72.7  300  22 11   5.2   2.9
  7250  27.3  81.1  205   7  4  10.7   5.8 |  23.1  73.6  300  23 12   7.3   4.0
  7000  28.1  82.6  205   7  4  10.2   5.6 |  23.6  74.5  300  25 13   7.2   3.9
  6750  28.9  84.0  210   7  4  10.0   5.5 |  24.1  75.4  300  26 13   9.1   5.0
  6500  29.7  85.5  210   7  4  10.5   5.8 |  24.9  76.8  300  26 13  10.5   5.8
  6250  30.5  86.9  210   7  3  11.4   6.2 |  25.7  78.3  300  25 13  11.1   6.1
  6000  31.3  88.3  210   7  3   9.3   5.1 |  26.5  79.7  300  24 13   9.8   5.4
  5750  32.1  89.8  215   7  3  15.2   8.3 |  27.2  81.0  300  24 12  11.9   6.5
  5500  33.8  92.8  215   6  3  31.9  17.5 |  28.4  83.1  300  21 11  19.2  10.5
________________________________________________________________________________

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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