Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 151304
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0704 MDT Tuesday, August 15, 2017

This forecast is for Tuesday, August 15, 2017:

If the trigger temperature of 80.3 F/26.8 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 280 ft/min (1.4 m/s)
   Maximum height of thermals.................. 11451 ft MSL (6166 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1230 MDT
Time of overdevelopment........................ None
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................. 8768 ft MSL (3483 ft AGL)
Thermal soaring outlook for Wednesday 08/16.... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 16826 ft MSL (11541 ft AGL)
Wave soaring outlook for Wednesday 08/16....... Fair

Remarks... Cold frontal passage today with increased clouds and storms after 3
           pm.

Sunrise/Sunset.................... 06:12:06 / 19:55:38 MDT
Total possible sunshine........... 13 hr 43 min 32 sec (823 min 32 sec)
Altitude of sun at 13:03:52 MDT... 64.02 degrees

Upper air data from rawinsonde observation taken on 08/15/2017 at 0600 MDT

Freezing level.................. 15293 ft MSL (10008 ft AGL)
Convective condensation level... 15221 ft MSL (9936 ft AGL)
Lifted condensation level....... 14865 ft MSL (9580 ft AGL)
Lifted index.................... -0.6
K index......................... +20.3

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  -60.5 -76.9   230   43   22   4.7   2.6   93.0 199.4    37.2      M    M
 45000  -63.3 -81.9   240   51   26  -4.2  -2.3   64.1 147.4    21.9      M    M
 40000  -56.1 -69.0   215   37   19   5.2   2.8   51.5 124.7    15.1      M    M
 38000  -51.9 -61.4   215   36   19   8.0   4.4   49.1 120.3    13.9      M    M
 36000  -47.0 -52.6   220   37   19   8.3   4.5   47.8 118.0    13.3      M    M
 34000  -42.1 -43.8   230   37   19   8.4   4.6   46.4 115.6    12.7      M    M
 32000  -36.7 -34.1   235   34   17   8.9   4.9   45.8 114.4    12.5      M    M
 30000  -32.6 -26.7   240   30   16   6.2   3.4   43.6 110.5    11.2      M    M
 29000  -30.1 -22.2   245   28   15   8.9   4.9   42.9 109.2    10.8      M    M
 28000  -27.5 -17.5   245   26   14   8.8   4.9   42.5 108.5    10.6      M    M
 27000  -24.2 -11.6   250   24   13   8.8   4.9   42.1 107.9    10.5      M    M
 26000  -21.5  -6.7   255   23   12   8.8   4.9   42.0 107.5    10.4      M    M
 25000  -18.9  -2.0   250   22   11   8.2   4.5   41.6 106.8    10.2      M    M
 24000  -16.9   1.6   250   22   11   6.5   3.5   40.3 104.5     9.3      M    M
 23000  -14.9   5.2   245   21   11   6.5   3.5   39.0 102.2     8.4      M    M
 22000  -13.0   8.6   240   20   10   6.5   3.5   37.8 100.1     7.5      M    M
 21000  -11.0  12.2   240   19   10   6.4   3.5   36.8  98.3     6.7      M    M
 20000   -9.4  15.1   235   18    9   5.4   3.0   35.4  95.7     5.6      M    M
 19500   -8.6  16.5   230   19   10   5.4   2.9   34.6  94.3     4.9      M    M
 19000   -7.8  18.0   230   19   10   1.9   1.0   33.9  93.0     4.3      M    M
 18500   -8.1  17.4   230   18    9   4.1   2.2   32.0  89.6     2.5      M    M
 18000   -7.1  19.2   225   17    9   7.5   4.1   31.6  89.0     2.1      M    M
 17500   -6.0  21.2   225   17    9   8.3   4.5   31.3  88.4     1.7      M    M
 17000   -4.7  23.5   220   16    8   8.9   4.9   31.2  88.2     1.6      M    M
 16500   -3.4  25.9   225   14    7   8.9   4.9   31.1  88.0     1.5      M    M
 16000   -2.1  28.2   240   12    6   8.9   4.9   31.0  87.8     1.4      M    M
 15500   -0.8  30.6   245   12    6   8.9   4.9   30.9  87.5     1.2      M    M
 15000    0.5  32.9   245   12    6   8.9   4.9   30.7  87.3     1.1      M    M
 14500    1.8  35.2   250   12    6   8.9   4.9   30.6  87.1     1.0      M    M
 14000    3.8  38.8   255   12    6   8.9   4.9   30.4  86.8     0.8      M    M
 13500    5.1  41.2   255   13    7   8.9   4.9   30.3  86.5     0.6      M    M
 13000    6.4  43.5   255   14    7   8.9   4.9   30.1  86.2     0.5      M    M
 12500    7.7  45.9   255   15    8   8.9   4.9   30.0  86.0     0.3      M    M
 12000    9.0  48.2   255   16    8   8.9   4.9   29.9  85.8     0.2      M    M
 11500   10.3  50.5   250   17    9   8.9   4.9   29.7  85.5    -0.0    477  2.4
 11000   11.6  52.9   250   18    9   8.9   4.9   29.5  85.2    -0.2    423  2.2
 10500   12.9  55.2   245   18    9   9.0   4.9   29.4  84.9    -0.4    369  1.9
 10250   13.6  56.5   245   18    9   8.9   4.9   29.3  84.7    -0.5    342  1.7
 10000   14.1  57.4   245   17    9   5.6   3.1   29.1  84.4    -0.7    319  1.6
  9750   14.4  57.9   240   15    8   3.2   1.7   28.6  83.6    -1.2    304  1.5
  9500   14.6  58.3   240   14    7   3.8   2.1   28.2  82.7    -1.6    289  1.5
  9250   14.9  58.8   235   12    6   3.7   2.0   27.7  81.9    -2.1    274  1.4
  9000   15.1  59.2   230   11    6   3.7   2.0   27.2  81.0    -2.6    260  1.3
  8750   15.4  59.7   230   10    5   3.7   2.0   26.8  80.2    -3.1    245  1.2
  8500   15.6  60.1   230   10    5   3.7   2.1   26.3  79.3    -3.6    230  1.2
  8250   15.8  60.4   235    9    5   3.7   2.1   25.8  78.5    -4.1    215  1.1
  8000   16.1  61.0   235    9    5   3.8   2.1   25.4  77.7    -4.6    200  1.0
  7750   16.3  61.3   240    8    4   3.7   2.0   24.9  76.8    -5.1    186  0.9
  7500   16.6  61.9   240    7    4   3.9   2.2   24.4  76.0    -5.6    171  0.9
  7250   16.8  62.2   245    7    3   3.2   1.8   24.0  75.2    -6.1    156  0.8
  7000   17.1  62.8   250    6    3   5.9   3.2   23.5  74.4    -6.5    141  0.7
  6750   17.3  63.1   250    6    3  -3.9  -2.2   23.1  73.6    -7.1    127  0.6
  6500   16.5  61.7   255    5    3  -8.4  -4.6   21.6  70.9    -8.6    143  0.7
  6250   16.4  61.5   255    5    3   2.4   1.3   20.7  69.3    -9.5    141  0.7
  6000   16.6  61.9   260    5    3   3.7   2.0   20.2  68.4   -10.1    127  0.6
  5750   16.8  62.2   260    5    3   3.4   1.9   19.8  67.6   -10.6    113  0.6
  5500   16.9  62.4   255    5    3  -1.2  -0.6   19.2  66.5   -11.2    103  0.5

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

           08/15/2017 at 0900 MDT          |       08/15/2017 at 1200 MDT
                                           |
CAPE...   +92.3    LI...       -0.7        | CAPE...  +600.2    LI...       -3.2
CINH...  -203.2    K Index... +21.6        | CINH...   -30.5    K Index... +19.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -61.3 -78.3  235  18  9   0.3   0.2 | -60.8 -77.4  230  18  9   0.2   0.1
 45000 -60.1 -76.2  230  23 12   2.4   1.3 | -59.9 -75.8  230  23 12   1.8   1.0
 40000 -56.3 -69.3  225  20 10   6.9   3.8 | -56.9 -70.4  230  20 10   7.1   3.9
 38000 -51.8 -61.2  220  18  9   7.4   4.1 | -51.6 -60.9  225  18  9   7.9   4.3
 36000 -46.8 -52.2  220  16  8   7.4   4.0 | -46.8 -52.2  220  16  8   7.9   4.3
 34000 -42.0 -43.6  220  15  8   8.2   4.5 | -41.8 -43.2  220  15  8   8.4   4.6
 32000 -37.0 -34.6  220  15  8   8.2   4.5 | -36.7 -34.1  220  14  7   8.5   4.6
 30000 -32.2 -26.0  215  14  7   8.1   4.4 | -31.8 -25.2  215  13  7   8.1   4.5
 29000 -29.7 -21.5  215  13  7   8.1   4.4 | -29.3 -20.7  215  13  7   8.1   4.5
 28000 -27.3 -17.1  210  13  6   8.0   4.4 | -26.9 -16.4  210  13  7   8.1   4.4
 27000 -25.1 -13.2  210  12  6   7.3   4.0 | -24.7 -12.5  210  13  6   7.2   3.9
 26000 -22.9  -9.2  215  11  6   7.3   4.0 | -22.5  -8.5  205  12  6   7.2   3.9
 25000 -20.7  -5.3  215  10  5   7.3   4.0 | -20.4  -4.7  205  12  6   7.2   3.9
 24000 -18.7  -1.7  215  10  5   6.7   3.7 | -18.4  -1.1  205  12  6   6.1   3.4
 23000 -16.7   1.9  215   9  5   6.7   3.7 | -16.6   2.1  205  11  6   6.1   3.4
 22000 -14.7   5.5  215   9  5   6.7   3.7 | -14.8   5.4  210  11  5   6.1   3.4
 21000 -12.8   9.0  215   9  4   6.4   3.5 | -13.0   8.6  210  10  5   6.0   3.3
 20000 -10.9  12.4  215   8  4   6.4   3.5 | -10.8  12.6  215   9  5   6.0   3.3
 19500  -9.5  14.9  215   8  4   6.4   3.5 |  -9.9  14.2  220   9  5   5.9   3.3
 19000  -8.5  16.7  215   8  4   6.9   3.8 |  -9.0  15.8  220   9  4   7.2   3.9
 18500  -7.5  18.5  215   7  4   7.0   3.8 |  -7.9  17.8  220   8  4   7.2   3.9
 18000  -6.5  20.3  215   7  3   7.2   4.0 |  -6.9  19.6  225   7  4   7.4   4.1
 17500  -5.5  22.1  220   6  3   7.6   4.2 |  -5.8  21.6  225   7  4   7.8   4.3
 17000  -4.4  24.1  220   5  3   7.6   4.2 |  -4.6  23.7  225   6  3   7.8   4.3
 16500  -3.2  26.2  225   5  2   8.6   4.7 |  -3.4  25.9  230   6  3   8.6   4.7
 16000  -2.0  28.4  230   4  2   8.6   4.7 |  -2.2  28.0  230   5  3   8.5   4.7
 15500  -0.7  30.7  240   4  2   8.7   4.8 |  -0.9  30.4  230   5  3   8.7   4.8
 15000   0.6  33.1  250   4  2   8.7   4.8 |   0.4  32.7  235   5  3   8.8   4.8
 14500   1.9  35.4  255   4  2   8.8   4.8 |   1.7  35.1  240   5  2   8.9   4.9
 14000   3.2  37.8  265   4  2   8.8   4.8 |   3.0  37.4  240   5  2   9.0   4.9
 13500   4.5  40.1  270   5  2   8.8   4.8 |   4.3  39.7  245   5  2   9.0   4.9
 13000   5.8  42.4  275   5  3   8.8   4.8 |   5.6  42.1  250   5  2   9.0   4.9
 12500   7.1  44.8  275   5  3   8.8   4.8 |   7.0  44.6  255   5  2   9.0   4.9
 12000   8.4  47.1  280   5  3   8.8   4.8 |   8.3  46.9  260   4  2   8.8   4.8
 11500   9.7  49.5  280   5  3   8.8   4.8 |   9.6  49.3  260   4  2   8.9   4.9
 11000  10.9  51.6  285   5  3   8.1   4.4 |  10.8  51.4  270   4  2   8.2   4.5
 10500  12.1  53.8  290   5  3   8.3   4.6 |  12.0  53.6  275   4  2   8.5   4.7
 10250  12.8  55.0  290   5  3   9.7   5.3 |  12.7  54.9  275   4  2   9.3   5.1
 10000  13.5  56.3  290   5  3   9.3   5.1 |  13.3  55.9  275   4  2   8.8   4.9
  9750  14.1  57.4  290   5  3   8.2   4.5 |  14.0  57.2  280   3  2   8.3   4.6
  9500  14.7  58.5  295   5  2   8.7   4.8 |  14.6  58.3  285   3  2   8.6   4.7
  9250  15.3  59.5  295   5  2   7.9   4.3 |  15.2  59.4  290   3  2   8.0   4.4
  9000  15.9  60.6  300   5  2   7.6   4.1 |  15.8  60.4  300   3  2   7.4   4.1
  8750  16.5  61.7  300   5  2   8.0   4.4 |  16.3  61.3  310   3  1   7.5   4.1
  8500  17.0  62.6  300   5  2   8.0   4.4 |  16.8  62.2  320   2  1   7.6   4.2
  8250  17.6  63.7  300   5  2   7.8   4.3 |  17.3  63.1  335   2  1   7.1   3.9
  8000  18.1  64.6  305   4  2   6.8   3.7 |  17.7  63.9  355   2  1   7.7   4.2
  7750  18.6  65.5  305   4  2   6.1   3.3 |  18.3  64.9  005   2  1   8.8   4.8
  7500  19.0  66.2  305   4  2   5.8   3.2 |  18.9  66.0  010   3  1   8.8   4.8
  7250  19.3  66.7  305   4  2   4.1   2.3 |  19.5  67.1  015   3  1   9.2   5.0
  7000  19.6  67.3  310   4  2   2.7   1.5 |  20.2  68.4  020   3  1   9.6   5.3
  6750  19.7  67.5  310   4  2   1.4   0.7 |  20.9  69.6  020   3  2   9.9   5.4
  6500  19.6  67.3  310   3  2   0.2   0.1 |  21.6  70.9  025   3  1  10.4   5.7
  6250  19.6  67.3  310   3  2   0.3   0.2 |  22.4  72.3  025   3  1  10.8   5.9
  6000  19.5  67.1  310   3  1  -0.4  -0.2 |  23.2  73.8  025   3  2  11.0   6.0
  5750  19.5  67.1  310   2  1   4.1   2.2 |  24.0  75.2  025   3  2  10.6   5.8
  5500  20.2  68.4  305   1  1  15.6   8.6 |  25.0  77.0  025   3  1  17.8   9.8

           08/15/2017 at 1500 MDT          |       08/15/2017 at 1800 MDT
                                           |
CAPE...  +403.3    LI...       -2.6        | CAPE...  +586.8    LI...       -2.5
CINH...    -4.6    K Index... +29.3        | CINH...   -41.3    K Index... +30.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -60.8 -77.4  225  17  9   0.4   0.2 | -60.8 -77.4  220  16  8   0.6   0.3
 45000 -59.7 -75.5  225  23 12   1.9   1.0 | -59.6 -75.3  220  21 11   1.6   0.9
 40000 -56.3 -69.3  230  20 10   8.1   4.4 | -56.6 -69.9  225  18  9   8.6   4.7
 38000 -51.8 -61.2  230  18  9   7.5   4.1 | -51.8 -61.2  220  16  8   7.9   4.3
 36000 -47.3 -53.1  225  15  8   7.5   4.1 | -47.1 -52.8  215  14  7   8.0   4.4
 34000 -42.2 -44.0  225  14  7   8.8   4.8 | -42.0 -43.6  215  13  7   8.6   4.7
 32000 -37.0 -34.6  220  14  7   8.8   4.8 | -36.9 -34.4  220  13  7   8.7   4.7
 30000 -31.5 -24.7  215  14  7   7.9   4.3 | -32.0 -25.6  220  14  7   7.9   4.3
 29000 -29.1 -20.4  215  14  7   7.9   4.3 | -29.1 -20.4  220  15  8   7.9   4.3
 28000 -26.8 -16.2  215  14  7   7.5   4.1 | -26.7 -16.1  215  16  8   7.4   4.1
 27000 -24.7 -12.5  215  14  7   6.6   3.6 | -24.8 -12.6  220  16  8   6.4   3.5
 26000 -22.8  -9.0  215  14  7   6.7   3.6 | -22.9  -9.2  220  16  8   6.4   3.5
 25000 -20.8  -5.4  220  15  7   6.7   3.7 | -20.9  -5.6  220  16  8   6.4   3.5
 24000 -19.0  -2.2  225  14  7   6.8   3.3 | -19.0  -2.2  220  15  8   6.6   3.6
 23000 -17.2   1.0  225  14  7   6.0   3.3 | -17.0   1.4  220  14  7   6.7   3.6
 22000 -15.5   4.1  230  13  7   6.0   3.3 | -15.0   5.0  225  13  6   6.6   3.6
 21000 -13.5   7.7  230  12  6   7.2   4.0 | -13.0   8.6  225  11  6   7.1   3.9
 20000 -11.4  11.5  235  11  6   7.3   4.0 | -10.9  12.4  225  10  5   7.1   3.9
 19500 -10.3  13.5  235  10  5   7.3   4.0 |  -9.9  14.2  225  10  5   7.2   3.9
 19000  -9.3  15.3  235  10  5   7.4   4.1 |  -8.9  16.0  225   9  5   7.3   4.0
 18500  -8.2  17.2  235   9  5   7.5   4.1 |  -7.8  18.0  225   9  4   7.5   4.1
 18000  -7.1  19.2  235   9  4   7.5   4.1 |  -6.7  19.9  225   8  4   7.5   4.1
 17500  -6.0  21.2  235   8  4   7.9   4.3 |  -5.7  21.7  225   8  4   7.8   4.3
 17000  -4.9  23.2  235   7  4   7.9   4.3 |  -4.6  23.7  220   7  4   7.8   4.3
 16500  -3.1  26.4  230   6  3   8.3   4.5 |  -3.5  25.7  220   6  3   8.1   4.5
 16000  -2.0  28.4  230   6  3   8.2   4.5 |  -1.7  28.9  210   5  3   8.4   4.6
 15500  -0.7  30.7  225   5  3   8.6   4.7 |  -0.5  31.1  200   4  2   8.2   4.5
 15000   0.5  32.9  225   5  2   8.7   4.8 |   0.7  33.3  195   4  2   8.2   4.5
 14500   1.8  35.2  220   4  2   8.9   4.9 |   1.9  35.4  180   3  2   8.5   4.6
 14000   3.2  37.8  220   3  2   9.2   5.0 |   3.2  37.8  175   3  1   8.8   4.9
 13500   4.5  40.1  215   3  2   9.2   5.0 |   4.5  40.1  165   2  1   8.9   4.9
 13000   5.9  42.6  205   2  1   9.3   5.1 |   5.8  42.4  155   2  1   9.2   5.1
 12500   7.2  45.0  190   2  1   9.2   5.1 |   7.2  45.0  145   2  1   9.2   5.1
 12000   8.6  47.5  175   2  1   9.5   5.2 |   8.6  47.5  135   1  1   9.5   5.2
 11500  10.0  50.0  145   1  1   9.5   5.2 |  10.0  50.0  130   1  0   9.5   5.2
 11000  11.3  52.3  120   1  1   9.2   5.1 |  11.3  52.3  105   1  0   9.0   4.9
 10500  12.7  54.9  100   2  1   9.5   5.2 |  12.7  54.9  060   1  0   9.4   5.2
 10250  13.4  56.1  100   2  1   9.9   5.5 |  13.4  56.1  045   1  0   9.6   5.3
 10000  14.1  57.4  100   2  1   9.9   5.4 |  14.1  57.4  030   1  0   9.1   5.0
  9750  14.9  58.8  095   2  1   9.9   5.4 |  14.7  58.5  015   1  0   9.0   4.9
  9500  15.6  60.1  090   2  1   9.8   5.4 |  15.4  59.7  005   1  0   9.2   5.1
  9250  16.3  61.3  090   2  1  10.2   5.6 |  16.1  61.0  360   1  1   8.4   4.6
  9000  17.1  62.8  085   2  1  10.1   5.5 |  16.7  62.1  360   1  1   8.6   4.7
  8750  17.8  64.0  085   2  1   9.5   5.2 |  17.4  63.3  355   1  1   9.6   5.2
  8500  18.5  65.3  080   2  1   9.6   5.3 |  18.1  64.6  350   1  1   9.4   5.2
  8250  19.2  66.6  080   2  1  10.1   5.6 |  18.8  65.8  350   2  1   9.0   4.9
  8000  20.0  68.0  075   2  1  10.2   5.6 |  19.4  66.9  350   2  1   9.0   5.0
  7750  20.7  69.3  075   2  1   9.8   5.4 |  20.1  68.2  350   2  1   9.5   5.2
  7500  21.5  70.7  075   2  1   9.9   5.4 |  20.8  69.4  345   2  1   9.4   5.1
  7250  22.2  72.0  075   2  1  10.1   5.6 |  21.5  70.7  345   2  1   9.3   5.1
  7000  23.0  73.4  070   2  1  10.2   5.6 |  22.2  72.0  350   2  1   9.3   5.1
  6750  23.7  74.7  070   2  1   9.9   5.4 |  22.9  73.2  350   2  1   9.4   5.1
  6500  24.5  76.1  070   2  1  10.1   5.5 |  23.5  74.3  350   2  1   9.3   5.1
  6250  25.2  77.4  070   2  1  10.5   5.8 |  24.2  75.6  350   2  1   9.1   5.0
  6000  26.0  78.8  070   2  1  11.1   6.1 |  24.9  76.8  350   2  1   9.1   5.0
  5750  26.8  80.2  065   2  1   8.7   4.8 |  25.5  77.9  355   2  1   9.0   4.9
  5500  27.5  81.5  070   2  1  13.5   7.4 |  26.2  79.2  345   2  1   9.1   5.0
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CINH (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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