Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 252359
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1759 MDT Saturday, October 25, 2014

This forecast is for Saturday, October 25, 2014:

If the trigger temperature of 76.0 F/24.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 137 ft/min (0.7 m/s)
   Maximum height of thermals.................. 5593 ft MSL (306 ft AGL)

Forecast maximum temperature................... 58.0 F/14.9 C
Time of trigger temperature.................... None
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................. 5410 ft MSL (122 ft AGL)
Thermal soaring outlook for Sunday 10/26....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Slight improvement.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 19784 ft MSL (14497 ft AGL)
Wave soaring outlook for Sunday 10/26.......... Fair

Remarks...

Sunrise/Sunset.................... 07:20:32 / 18:07:30 MDT
Total possible sunshine........... 10 hr 46 min 58 sec (646 min 58 sec)
Altitude of sun at 12:43:37 MDT... 38.00 degrees

Upper air data from numerical model forecast valid on 10/25/2014 at 0600 MDT

Freezing level.................. 16039 ft MSL (10752 ft AGL)
Convective condensation level... 23912 ft MSL (18625 ft AGL)
Lifted condensation level....... 14476 ft MSL (9188 ft AGL)
Lifted index.................... +16.2
K index......................... -24.3

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  -69.0 -92.2   275   36   19   2.9   1.6      M     M       M      M    M
 45000  -63.8 -82.8   275   41   21   5.1   2.8      M     M       M      M    M
 40000  -55.6 -68.1   260   43   22   6.8   3.8      M     M       M      M    M
 38000  -51.4 -60.5   260   43   22   6.9   3.8      M     M       M      M    M
 36000  -47.3 -53.1   260   43   22   6.8   3.7      M     M       M      M    M
 34000  -42.5 -44.5   260   41   21   8.2   4.5      M     M       M      M    M
 32000  -37.6 -35.7   255   39   20   8.1   4.5      M     M       M      M    M
 30000  -32.7 -26.9   255   36   18   8.4   4.6   43.3 110.0    21.9      M    M
 29000  -30.2 -22.4   255   34   18   8.4   4.6   42.8 109.1    21.8      M    M
 28000  -27.0 -16.6   255   32   16   8.4   4.6   42.3 108.1    21.7      M    M
 27000  -24.5 -12.1   260   28   15   8.3   4.6   41.6 107.0    21.5      M    M
 26000  -22.0  -7.6   265   25   13   8.3   4.6   41.1 106.0    21.3      M    M
 25000  -19.5  -3.1   270   22   11   8.1   4.5   40.7 105.3    21.2      M    M
 24000  -17.2   1.0   270   22   11   7.6   4.1   39.9 103.7    20.8      M    M
 23000  -15.0   5.0   275   22   11   7.6   4.1   39.0 102.3    20.3      M    M
 22000  -12.7   9.1   275   22   11   7.5   4.1   38.4 101.0    20.0      M    M
 21000  -10.5  13.1   270   23   12   7.4   4.0   37.4  99.4    19.4      M    M
 20000   -8.3  17.1   265   24   12   7.4   4.0   36.6  97.9    18.9      M    M
 19500   -7.2  19.0   265   25   13   7.4   4.0   36.2  97.2    18.7      M    M
 19000   -6.1  21.0   265   25   13   7.3   4.0   35.8  96.5    18.5      M    M
 18500   -5.0  23.0   265   24   12   7.3   4.0   35.4  95.7    18.2      M    M
 18000   -3.9  25.0   265   24   12   7.0   3.8   35.0  95.0    17.9      M    M
 17500   -2.9  26.8   270   22   12   6.5   3.6   34.5  94.0    17.5      M    M
 17000   -2.0  28.4   270   21   11   6.5   3.6   33.9  93.0    17.1      M    M
 16500   -1.0  30.2   275   20   10   6.1   3.3   33.3  92.0    16.7      M    M
 16000   -0.1  31.8   275   18    9   6.1   3.3   32.7  90.9    16.2      M    M
 15500    0.8  33.4   280   17    9   5.7   3.1   32.1  89.8    15.8      M    M
 15000    1.6  34.9   280   15    8   5.5   3.0   31.4  88.5    15.2      M    M
 14500    2.8  37.0   285   12    6   5.6   3.1   30.3  86.6    14.4      M    M
 14000    3.7  38.7   285   10    5   5.6   3.1   29.6  85.3    13.8      M    M
 13500    4.5  40.1   290    9    5   6.1   3.4   29.0  84.2    13.3      M    M
 13000    5.5  41.9   290    8    4   6.4   3.5   28.4  83.2    12.8      M    M
 12500    6.4  43.5   295    7    4   6.3   3.5   27.9  82.2    12.4      M    M
 12000    7.3  45.1   300    7    4   6.2   3.4   27.3  81.2    11.9      M    M
 11500    8.2  46.8   300    7    4   6.2   3.4   26.8  80.2    11.4      M    M
 11000    9.1  48.4   310    7    3   5.9   3.2   26.2  79.1    10.9      M    M
 10500   10.0  50.0   315    7    3   3.7   2.0   25.6  78.1    10.4      M    M
 10250   10.2  50.4   315    7    3   5.1   2.8   25.1  77.1     9.9      M    M
 10000   10.8  51.4   320    7    3   9.8   5.4   25.0  76.9     9.8      M    M
  9750   11.5  52.7   320    7    4  10.1   5.5   25.0  76.9     9.8      M    M
  9500   12.2  54.0   325    7    4   8.0   4.4   25.0  76.9     9.8      M    M
  9250   12.7  54.9   325    7    4   5.6   3.0   24.7  76.4     9.5      M    M
  9000   13.2  55.8   330    7    4   7.5   4.1   24.4  76.0     9.3      M    M
  8750   13.8  56.8   335    7    4   8.7   4.8   24.3  75.8     9.2      M    M
  8500   14.4  57.9   340    8    4   7.8   4.3   24.2  75.6     9.1      M    M
  8250   14.9  58.8   340    8    4   7.1   3.9   24.0  75.2     8.9      M    M
  8000   15.4  59.7   345    8    4   7.9   4.3   23.8  74.9     8.8      M    M
  7750   16.0  60.8   345    8    4   8.2   4.5   23.7  74.7     8.6      M    M
  7500   16.6  61.9   350    8    4   6.4   3.5   23.5  74.4     8.5      M    M
  7250   17.0  62.6   350    8    4   5.0   2.8   23.2  73.8     8.2      M    M
  7000   17.4  63.3   350    7    4   6.7   3.7   22.9  73.2     7.8      M    M
  6750   17.8  64.0   355    7    4   4.9   2.7   22.7  72.8     7.6      M    M
  6500   18.0  64.4   350    6    3  -0.4  -0.2   22.1  71.7     7.0      M    M
  6250   18.0  64.4   345    4    2   2.6   1.4   21.3  70.4     6.3      M    M
  6000   18.0  64.4   335    3    2  -9.6  -5.3   20.6  69.1     5.6      M    M
  5750   16.1  61.0   305    2    1 -36.4 -20.0   18.1  64.5     3.0      M    M
  5500   12.8  55.0   220    2    1 -43.6 -23.9   14.2  57.6    -1.0    159  0.8

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

           10/25/2014 at 0900 MDT          |       10/25/2014 at 1200 MDT
                                           |
K index... -17.7  LI... +7.5               | K index... -14.9  LI... +6.9
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -69.5 -93.1  265  38 19   3.4   1.8 | -69.0 -92.2  250  35 18   3.5   1.9
 45000 -63.7 -82.7  260  41 21   5.2   2.9 | -63.2 -81.8  255  39 20   5.1   2.8
 40000 -55.7 -68.3  255  44 23   6.8   3.7 | -54.9 -66.8  240  51 26   6.8   3.7
 38000 -51.7 -61.1  255  42 22   6.7   3.7 | -50.8 -59.4  235  49 25   6.8   3.8
 36000 -47.7 -53.9  250  41 21   6.7   3.7 | -46.7 -52.1  235  46 24   6.8   3.7
 34000 -42.6 -44.7  245  40 21   7.8   4.3 | -42.2 -44.0  235  45 23   7.5   4.1
 32000 -37.9 -36.2  245  40 20   7.8   4.3 | -37.7 -35.9  230  43 22   7.5   4.1
 30000 -32.7 -26.9  245  37 19   8.6   4.7 | -32.8 -27.0  235  39 20   8.5   4.7
 29000 -30.1 -22.2  245  35 18   8.6   4.7 | -30.2 -22.4  235  37 19   8.5   4.7
 28000 -27.6 -17.7  245  34 17   8.0   4.4 | -27.1 -16.8  240  34 18   7.9   4.3
 27000 -25.3 -13.5  245  29 15   7.6   4.1 | -24.8 -12.6  235  33 17   7.8   4.3
 26000 -23.0  -9.4  240  25 13   7.6   4.2 | -22.4  -8.3  230  31 16   7.8   4.3
 25000 -20.8  -5.4  235  21 11   7.6   4.2 | -20.1  -4.2  225  30 15   7.6   4.2
 24000 -18.4  -1.1  235  20 11   7.9   4.3 | -18.1  -0.6  225  30 16   6.7   3.7
 23000 -16.0   3.2  235  21 11   7.9   4.3 | -16.1   3.0  225  31 16   6.7   3.7
 22000 -13.7   7.3  240  22 11   7.8   4.3 | -14.1   6.6  225  32 16   6.8   3.7
 21000 -11.5  11.3  240  22 11   7.2   3.9 | -12.0  10.4  225  32 16   7.1   3.9
 20000  -9.3  15.3  240  22 12   7.2   3.9 |  -9.9  14.2  230  32 17   7.1   3.9
 19500  -8.2  17.2  240  23 12   7.3   4.0 |  -8.9  16.0  235  32 17   7.1   3.9
 19000  -7.2  19.0  240  22 12   5.6   3.1 |  -7.8  18.0  235  32 17   6.6   3.6
 18500  -6.4  20.5  245  22 11   5.4   3.0 |  -6.9  19.6  240  32 16   6.7   3.7
 18000  -5.6  21.9  245  21 11   5.5   3.0 |  -5.9  21.4  240  32 16   7.2   3.9
 17500  -4.8  23.4  245  21 11   5.8   3.2 |  -4.7  23.5  245  31 16   7.9   4.3
 17000  -3.5  25.7  245  20 10   6.0   3.3 |  -3.5  25.7  245  31 16   7.9   4.4
 16500  -2.5  27.5  245  20 10   6.5   3.6 |  -2.4  27.7  245  30 15   7.3   4.0
 16000  -1.5  29.3  245  19 10   6.5   3.6 |  -1.3  29.7  245  28 14   7.4   4.1
 15500  -0.6  30.9  250  17  9   6.5   3.5 |  -0.2  31.6  245  26 13   6.8   3.7
 15000   0.4  32.7  250  16  8   6.4   3.5 |   0.8  33.4  245  23 12   6.4   3.5
 14500   1.4  34.5  255  15  8   7.2   3.9 |   1.7  35.1  245  20 10   6.3   3.5
 14000   2.5  36.5  255  14  7   7.3   4.0 |   3.1  37.6  245  16  8   6.1   3.4
 13500   3.5  38.3  260  12  6   7.2   4.0 |   4.0  39.2  240  14  7   5.9   3.2
 13000   4.6  40.3  260  11  6   7.2   3.9 |   4.9  40.8  235  11  6   5.8   3.2
 12500   5.7  42.3  265  10  5   7.2   3.9 |   5.7  42.3  230   9  5   5.9   3.3
 12000   6.7  44.1  270   9  4   7.1   3.9 |   6.6  43.9  215   8  4   6.1   3.3
 11500   7.8  46.0  275   7  4   7.1   3.9 |   7.5  45.5  200   7  4   6.5   3.5
 11000   8.8  47.8  280   6  3   6.8   3.7 |   8.5  47.3  185   6  3   6.7   3.7
 10500   9.8  49.6  285   5  2   4.4   2.4 |   9.5  49.1  170   6  3   3.4   1.9
 10250  10.0  50.0  290   5  2   4.2   2.3 |   9.6  49.3  170   6  3   4.8   2.6
 10000  10.6  51.1  295   4  2   9.1   5.0 |  10.3  50.5  165   6  3  10.8   5.9
  9750  11.3  52.3  310   4  2  10.1   5.5 |  11.1  52.0  160   6  3  10.2   5.6
  9500  12.0  53.6  325   4  2   8.1   4.4 |  11.8  53.2  150   6  3   8.7   4.8
  9250  12.5  54.5  330   4  2   5.6   3.1 |  12.4  54.3  150   6  3   7.1   3.9
  9000  12.9  55.2  340   4  2   7.4   4.1 |  13.0  55.4  145   6  3   9.5   5.2
  8750  13.5  56.3  345   4  2   9.0   4.9 |  13.8  56.8  140   6  3  10.7   5.9
  8500  14.2  57.6  355   5  2   7.6   4.2 |  14.5  58.1  135   6  3   8.3   4.5
  8250  14.7  58.5  360   5  2   6.7   3.7 |  15.0  59.0  130   7  3   6.6   3.6
  8000  15.2  59.4  360   5  3   7.2   3.9 |  15.5  59.9  125   7  4   7.2   4.0
  7750  15.7  60.3  005   5  3   7.1   3.9 |  16.1  61.0  120   8  4   7.7   4.2
  7500  16.2  61.2  010   5  3   5.7   3.1 |  16.6  61.9  120   8  4   8.6   4.7
  7250  16.6  61.9  010   5  3   4.6   2.5 |  17.3  63.1  125   8  4   8.9   4.9
  7000  16.9  62.4  015   5  2   5.9   3.3 |  17.9  64.2  125   8  4   9.0   4.9
  6750  17.3  63.1  015   5  2   1.6   0.9 |  18.6  65.5  130   9  4   9.3   5.1
  6500  17.1  62.8  005   4  2  -4.9  -2.7 |  19.3  66.7  135   8  4   9.2   5.1
  6250  16.8  62.2  350   3  2  -1.5  -0.8 |  19.9  67.8  140   7  4   9.3   5.1
  6000  16.4  61.5  320   3  1 -13.4  -7.3 |  20.6  69.1  150   6  3   9.2   5.0
  5750  14.4  57.9  275   3  1 -33.5 -18.4 |  21.3  70.3  155   5  3  10.1   5.5
  5500  11.7  53.1  235   3  2 -31.3 -17.2 |  22.1  71.8  155   4  2  11.8   6.5

           10/25/2014 at 1500 MDT          |       10/25/2014 at 1800 MDT
                                           |
K index... -5.2  LI... +5.6                | K index... +10.4  LI... +3.7
CAPE... 0.0  CIN... -0.7                   | CAPE... 0.0  CIN... -0.3
                                           |
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 -70.0 -94.0  240  47 24   3.8   2.1 | -69.7 -93.5  245  49 25   3.4   1.9
 45000 -63.5 -82.3  240  44 23   5.2   2.9 | -63.4 -82.1  240  54 28   5.6   3.0
 40000 -55.5 -67.9  235  53 27   7.0   3.9 | -55.0 -67.0  230  53 27   6.3   3.4
 38000 -51.3 -60.3  230  51 26   6.9   3.8 | -51.3 -60.3  230  56 29   6.2   3.4
 36000 -47.2 -53.0  230  50 26   6.9   3.8 | -47.6 -53.7  225  58 30   6.2   3.4
 34000 -42.9 -45.2  230  48 25   7.2   4.0 | -43.2 -45.8  225  57 29   7.8   4.3
 32000 -38.6 -37.5  230  47 24   7.3   4.0 | -38.5 -37.3  230  54 28   7.8   4.3
 30000 -33.1 -27.6  230  43 22   8.5   4.7 | -33.2 -27.8  225  50 26   8.1   4.4
 29000 -30.5 -22.9  230  41 21   8.5   4.7 | -30.7 -23.3  225  48 25   8.1   4.4
 28000 -28.0 -18.4  230  39 20   8.2   4.5 | -28.3 -18.9  225  46 24   8.0   4.4
 27000 -25.6 -14.1  225  39 20   8.0   4.4 | -26.0 -14.8  225  45 23   7.9   4.3
 26000 -23.2  -9.8  225  39 20   8.0   4.4 | -23.6 -10.5  230  44 23   7.9   4.3
 25000 -20.8  -5.4  225  39 20   8.1   4.4 | -21.2  -6.2  230  43 22   8.0   4.4
 24000 -18.6  -1.5  225  40 20   7.1   3.9 | -19.1  -2.4  235  41 21   7.1   3.9
 23000 -16.5   2.3  230  40 21   7.1   3.9 | -16.9   1.6  240  39 20   7.1   3.9
 22000 -14.4   6.1  235  41 21   7.1   3.9 | -14.8   5.4  245  37 19   7.1   3.9
 21000 -12.3   9.9  235  40 21   6.9   3.8 | -12.8   9.0  245  36 18   6.6   3.6
 20000 -10.2  13.6  235  38 20   6.9   3.8 | -10.9  12.4  250  35 18   6.6   3.6
 19500  -9.2  15.4  235  37 19   6.9   3.8 |  -9.9  14.2  250  34 18   6.7   3.7
 19000  -8.1  17.4  240  36 19   7.1   3.9 |  -9.0  15.8  250  34 17   5.5   3.0
 18500  -7.1  19.2  240  35 18   7.1   3.9 |  -8.2  17.2  250  32 17   5.2   2.9
 18000  -6.0  21.2  240  33 17   7.1   3.9 |  -7.5  18.5  255  31 16   5.4   3.0
 17500  -5.0  23.0  245  32 16   7.1   3.9 |  -6.6  20.1  255  28 14   6.9   3.8
 17000  -3.9  25.0  245  30 15   7.1   3.9 |  -5.6  21.9  255  25 13   6.8   3.8
 16500  -2.8  27.0  245  28 15   8.0   4.4 |  -4.6  23.7  255  22 11   8.6   4.7
 16000  -1.6  29.1  245  27 14   8.1   4.4 |  -3.2  26.2  255  20 11   9.0   4.9
 15500  -0.4  31.3  250  25 13   7.8   4.3 |  -1.9  28.6  255  19 10   9.2   5.0
 15000   1.2  34.2  250  23 12   7.5   4.1 |   0.2  32.4  250  19 10   9.6   5.2
 14500   2.4  36.3  250  22 11   7.5   4.1 |   1.6  34.9  245  19 10   9.1   5.0
 14000   3.5  38.3  250  21 11   7.5   4.1 |   2.9  37.2  245  19 10   8.9   4.9
 13500   4.6  40.3  250  20 10   7.0   3.8 |   4.2  39.6  240  19 10   8.6   4.7
 13000   5.5  41.9  245  19 10   6.5   3.5 |   5.5  41.9  235  19 10   8.2   4.5
 12500   6.5  43.7  235  18  9   6.4   3.5 |   6.7  44.1  230  18  9   7.8   4.3
 12000   7.4  45.3  230  17  9   6.3   3.4 |   7.7  45.9  220  17  9   6.7   3.7
 11500   8.3  46.9  220  16  8   6.5   3.6 |   8.7  47.7  215  16  8   6.8   3.7
 11000   9.4  48.9  210  15  7   7.3   4.0 |   9.7  49.5  200  16  8   6.5   3.6
 10500  10.5  50.9  200  14  7   3.9   2.1 |  10.7  51.3  190  15  8   2.8   1.5
 10250  10.6  51.1  195  14  7   4.0   2.2 |  10.8  51.4  185  15  8   5.4   2.9
 10000  11.2  52.2  190  13  6   8.7   4.8 |  11.6  52.9  185  14  7  12.2   6.7
  9750  11.7  53.1  185  12  6   7.7   4.2 |  12.4  54.3  180  13  7  10.6   5.8
  9500  12.3  54.1  180  11  6   7.2   4.0 |  13.2  55.8  175  12  6  10.0   5.5
  9250  12.8  55.0  175  10  5   6.1   3.4 |  13.9  57.0  170  11  6   7.7   4.2
  9000  13.3  55.9  165   9  4   7.8   4.3 |  14.4  57.9  165  11  5   8.3   4.6
  8750  13.9  57.0  155   8  4   8.8   4.8 |  15.1  59.2  160  10  5   9.2   5.0
  8500  14.5  58.1  145   7  4   9.1   5.0 |  15.8  60.4  155   9  5   8.9   4.9
  8250  15.2  59.4  140   7  4   9.7   5.3 |  16.4  61.5  150   9  5   9.1   5.0
  8000  16.0  60.8  140   7  3  10.0   5.5 |  17.1  62.8  145   8  4   8.8   4.8
  7750  16.7  62.1  140   7  3  10.4   5.7 |  17.7  63.9  140   8  4   8.5   4.7
  7500  17.5  63.5  140   7  3  10.0   5.5 |  18.4  65.1  130   7  4   8.5   4.7
  7250  18.2  64.8  140   7  3   9.6   5.3 |  19.0  66.2  125   7  4   8.5   4.6
  7000  18.9  66.0  135   6  3   9.7   5.3 |  19.7  67.5  120   7  4   8.6   4.7
  6750  19.7  67.5  135   6  3   9.9   5.4 |  20.3  68.5  110   7  4   8.7   4.8
  6500  20.4  68.7  135   6  3  10.2   5.6 |  20.9  69.6  105   7  4   8.1   4.4
  6250  21.2  70.2  135   6  3  10.6   5.8 |  21.5  70.7  095   7  3   7.3   4.0
  6000  21.9  71.4  135   6  3   9.4   5.1 |  22.1  71.8  085   7  3   8.8   4.8
  5750  22.6  72.7  135   6  3  11.2   6.1 |  22.7  72.9  080   7  4   5.9   3.3
  5500  23.7  74.7  130   5  3  17.6   9.6 |  22.7  72.9  070   6  3  -3.6  -2.0
________________________________________________________________________________

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.

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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