Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 200126
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1926 MDT Tuesday, May 19, 2015

This forecast is for Wednesday, May 20, 2015:

If the trigger temperature of 56.3 F/13.5 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 69 ft/min (0.4 m/s)
   Maximum height of thermals.................. 8640 ft MSL (3333 ft AGL)

Forecast maximum temperature................... 52.0 F/11.6 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7973 ft MSL (2666 ft AGL)
Thermal soaring outlook for Thursday 05/21..... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Improving.
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 35046 ft MSL (29739 ft AGL)
Wave soaring outlook for Thursday 05/21........ Good

Remarks...

Sunrise/Sunset.................... 05:40:56 / 20:10:54 MDT
Total possible sunshine........... 14 hr 29 min 58 sec (869 min 58 sec)
Altitude of sun at 12:56:07 MDT... 70.24 degrees

Upper air data from numerical model forecast valid on 05/20/2015 at 0600 MDT

Freezing level.................. 7174 ft MSL (1867 ft AGL)
Additional freezing levels...... 7934 ft MSL (2627 ft AGL)
                                 10957 ft MSL (5650 ft AGL)
Convective condensation level... 12990 ft MSL (7683 ft AGL)
Lifted condensation level....... 9907 ft MSL (4601 ft AGL)
Lifted index.................... +4.3
K index......................... +19.4

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  -57.2 -71.0   245   38   20   2.0   1.1      M     M       M      M    M
 45000  -54.3 -65.7   250   54   28   0.3   0.2      M     M       M      M    M
 40000  -53.9 -65.0   260   68   35   0.3   0.2      M     M       M      M    M
 38000  -52.9 -63.2   260   72   37   2.4   1.3      M     M       M      M    M
 36000  -51.4 -60.5   260   75   38   2.4   1.3      M     M       M      M    M
 34000  -49.3 -56.7   265   76   39   6.6   3.6      M     M       M      M    M
 32000  -45.3 -49.5   265   72   37   6.7   3.7      M     M       M      M    M
 30000  -41.1 -42.0   265   62   32   5.1   2.8   35.1  95.3    18.1      M    M
 29000  -39.6 -39.3   265   53   27   5.1   2.8   33.2  91.8    16.9      M    M
 28000  -38.0 -36.4   270   44   23   5.1   2.8   31.5  88.7    15.7      M    M
 27000  -36.3 -33.3   270   36   19   7.7   4.2   30.0  86.1    14.8      M    M
 26000  -34.1 -29.4   270   33   17   7.6   4.2   29.1  84.4    14.2      M    M
 25000  -31.8 -25.2   265   29   15   7.6   4.2   28.3  83.0    13.7      M    M
 24000  -29.5 -21.1   265   26   13   8.6   4.7   27.7  81.8    13.4      M    M
 23000  -26.8 -16.2   265   25   13   8.9   4.9   27.3  81.1    13.2      M    M
 22000  -24.2 -11.6   265   24   12   8.9   4.9   27.0  80.6    13.1      M    M
 21000  -21.6  -6.9   265   22   12   7.1   3.9   26.6  79.9    12.9      M    M
 20000  -19.4  -2.9   265   21   11   7.4   4.0   25.7  78.2    12.3      M    M
 19500  -18.4  -1.1   265   20   10   7.4   4.1   25.3  77.5    12.0      M    M
 19000  -17.3   0.9   270   20   10   7.4   4.1   24.9  76.8    11.7      M    M
 18500  -16.2   2.8   270   19   10   6.8   3.7   24.5  76.1    11.4      M    M
 18000  -15.2   4.6   270   18   10   6.7   3.7   23.9  75.1    11.0      M    M
 17500  -14.3   6.3   270   18    9   6.7   3.7   23.4  74.2    10.6      M    M
 17000  -13.3   8.1   275   17    9   6.7   3.7   22.9  73.2    10.1      M    M
 16500  -12.3   9.9   275   16    8   6.7   3.7   22.4  72.3     9.7      M    M
 16000  -11.3  11.7   275   15    8   7.3   4.0   21.9  71.4     9.3      M    M
 15500   -9.7  14.5   280   14    7   7.3   4.0   21.3  70.3     8.8      M    M
 15000   -8.6  16.5   280   14    7   7.7   4.2   20.9  69.6     8.5      M    M
 14500   -7.5  18.5   285   14    7   7.7   4.2   20.6  69.0     8.2      M    M
 14000   -6.3  20.7   290   14    7   7.9   4.3   20.2  68.4     7.9      M    M
 13500   -5.1  22.8   290   15    8   7.9   4.3   19.9  67.9     7.7      M    M
 13000   -4.0  24.8   295   17    9   7.6   4.2   19.6  67.3     7.4      M    M
 12500   -2.9  26.8   295   19   10   7.7   4.2   19.3  66.7     7.1      M    M
 12000   -1.8  28.8   300   22   11   6.7   3.7   18.9  66.0     6.8      M    M
 11500   -0.9  30.4   300   24   12   6.6   3.6   18.3  65.0     6.3      M    M
 11000   -0.0  32.0   300   25   13   5.1   2.8   17.8  64.0     5.7      M    M
 10500    0.7  33.3   300   23   12   5.1   2.8   17.0  62.5     4.9      M    M
 10250    1.0  33.8   300   22   11   3.3   1.8   16.6  61.8     4.6      M    M
 10000    1.1  34.0   295   22   11   1.3   0.7   16.0  60.7     4.0      M    M
  9750    1.2  34.2   295   20   10   1.6   0.9   15.3  59.5     3.3      M    M
  9500    1.3  34.3   295   18    9   2.2   1.2   14.7  58.4     2.7      M    M
  9250    1.4  34.5   295   16    8   0.5   0.3   14.1  57.3     2.1      M    M
  9000    1.4  34.5   295   15    8  -1.9  -1.0   13.2  55.8     1.3      M    M
  8750    1.2  34.2   295   14    7  -2.5  -1.4   12.3  54.1     0.4      M    M
  8500    1.0  33.8   295   12    6  -2.6  -1.4   11.3  52.4    -0.5    269  1.4
  8250    0.7  33.3   295   10    5  -5.3  -2.9   10.3  50.6    -1.5    269  1.4
  8000    0.2  32.4   295    8    4  -7.6  -4.2    9.0  48.2    -2.8    278  1.4
  7750   -0.4  31.3   295    6    3  -6.2  -3.4    7.7  45.9    -4.1    286  1.5
  7500   -0.6  30.9   295    4    2   0.3   0.2    6.7  44.0    -5.1    287  1.5
  7250   -0.3  31.5   295    3    2   8.6   4.7    6.3  43.4    -5.5    269  1.4
  7000    0.4  32.7   295    2    1  10.3   5.7    6.3  43.4    -5.5    241  1.2
  6750    1.1  34.0   300    1    0   9.6   5.3    6.4  43.4    -5.5    212  1.1
  6500    1.7  35.1   000    0    0   6.0   3.3    6.2  43.2    -5.7    186  0.9
  6250    2.0  35.6   085    2    1   3.6   2.0    5.8  42.5    -6.1    170  0.9
  6000    2.3  36.1   090    4    2   4.2   2.3    5.4  41.7    -6.6    154  0.8
  5750    2.6  36.7   090    5    3   4.4   2.4    5.0  40.9    -7.0    138  0.7
  5500    3.0  37.4   090    5    3   7.2   4.0    4.7  40.4    -7.4    119  0.6

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

           05/20/2015 at 0900 MDT          |       05/20/2015 at 1200 MDT
                                           |
K index... +17.5  LI... +274.1             | K index... +18.9  LI... +274.0
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 -57.9 -72.2  245  41 21   2.1   1.2 | -58.9 -74.0  245  41 21   1.5   0.8
 45000 -55.0 -67.0  250  52 27  -0.7  -0.4 | -56.9 -70.4  245  55 28  -0.7  -0.4
 40000 -56.2 -69.2  260  73 38  -0.7  -0.4 | -58.0 -72.4  255  73 37  -0.6  -0.3
 38000 -54.6 -66.3  260  78 40   4.2   2.3 | -55.7 -68.3  255  76 39   5.4   3.0
 36000 -52.1 -61.8  265  82 42   4.2   2.3 | -52.5 -62.5  260  77 40   5.4   3.0
 34000 -49.0 -56.2  265  82 42   7.3   4.0 | -48.8 -55.8  260  77 39   7.5   4.1
 32000 -44.6 -48.3  265  78 40   7.3   4.0 | -44.3 -47.7  260  72 37   7.5   4.1
 30000 -39.8 -39.6  270  71 36   6.9   3.8 | -39.2 -38.6  265  66 34   7.9   4.3
 29000 -37.7 -35.9  270  66 34   6.9   3.8 | -36.8 -34.2  265  64 33   7.9   4.3
 28000 -35.6 -32.1  270  61 32   6.9   3.8 | -34.4 -29.9  270  61 32   7.9   4.3
 27000 -33.7 -28.7  270  56 29   5.2   2.8 | -32.3 -26.1  270  58 30   5.8   3.2
 26000 -32.1 -25.8  270  48 25   5.4   3.0 | -30.5 -22.9  270  53 27   5.9   3.2
 25000 -30.5 -22.9  265  40 21   5.4   3.0 | -28.7 -19.7  270  48 25   5.9   3.2
 24000 -28.8 -19.8  265  33 17   7.6   4.2 | -26.9 -16.4  275  43 22   5.9   3.2
 23000 -26.3 -15.3  265  31 16   8.2   4.5 | -25.2 -13.4  270  36 18   5.9   3.2
 22000 -23.9 -11.0  260  29 15   8.2   4.5 | -23.4 -10.1  265  29 15   5.9   3.3
 21000 -21.6  -6.9  260  26 13   6.3   3.5 | -21.5  -6.7  260  24 12   7.6   4.1
 20000 -19.6  -3.3  260  23 12   6.6   3.6 | -19.3  -2.7  265  23 12   7.5   4.1
 19500 -18.7  -1.7  260  22 11   6.6   3.6 | -18.2  -0.8  265  23 12   7.5   4.1
 19000 -17.7   0.1  255  20 10   6.6   3.6 | -17.1   1.2  270  22 11   7.5   4.1
 18500 -16.7   1.9  260  19 10   6.9   3.8 | -16.0   3.2  270  22 11   7.6   4.2
 18000 -15.7   3.7  260  19 10   7.0   3.8 | -14.9   5.2  270  21 11   7.6   4.2
 17500 -14.7   5.5  260  18  9   7.3   4.0 | -13.8   7.2  275  21 11   7.5   4.1
 17000 -13.5   7.7  265  17  9   7.9   4.3 | -12.7   9.1  275  21 11   7.4   4.0
 16500 -12.3   9.9  265  16  8   7.9   4.3 | -11.6  11.1  280  22 11   7.4   4.0
 16000 -11.2  11.8  270  16  8   8.2   4.5 | -10.6  12.9  280  23 12   6.6   3.6
 15500  -9.3  15.3  280  17  9   8.0   4.4 |  -9.2  15.4  285  25 13   6.7   3.7
 15000  -8.3  17.1  285  19 10   7.0   3.8 |  -8.2  17.2  290  26 14   6.9   3.8
 14500  -7.2  19.0  290  21 11   7.0   3.9 |  -7.2  19.0  290  27 14   6.9   3.8
 14000  -6.2  20.8  290  22 12   6.8   3.7 |  -6.0  21.2  290  27 14   8.3   4.6
 13500  -5.2  22.6  295  24 12   6.9   3.8 |  -4.8  23.4  290  27 14   8.2   4.5
 13000  -4.3  24.3  295  25 13   6.8   3.7 |  -3.6  25.5  295  27 14   8.0   4.4
 12500  -3.3  26.1  295  25 13   6.8   3.7 |  -2.5  27.5  295  26 13   8.1   4.4
 12000  -2.3  27.9  295  25 13   7.3   4.0 |  -1.4  29.5  295  25 13   7.1   3.9
 11500  -1.2  29.8  295  24 12   7.5   4.1 |  -0.4  31.3  295  23 12   7.2   4.0
 11000  -0.2  31.6  295  23 12   6.2   3.4 |   0.6  33.1  295  21 11   6.0   3.3
 10500   0.7  33.3  295  21 11   6.6   3.6 |   1.4  34.5  290  17  9   6.8   3.7
 10250   1.1  34.0  295  20 10   4.1   2.3 |   1.9  35.4  290  15  8   3.2   1.7
 10000   1.3  34.3  295  19 10   3.0   1.6 |   1.9  35.4  290  15  8   0.9   0.5
  9750   1.6  34.9  295  18  9   4.7   2.6 |   2.1  35.8  290  13  7   2.7   1.5
  9500   1.9  35.4  295  16  8   5.0   2.8 |   2.3  36.1  290  11  5   2.7   1.5
  9250   2.3  36.1  295  15  8   2.9   1.6 |   2.4  36.3  285   9  4   0.1   0.1
  9000   2.3  36.1  290  14  7   0.2   0.1 |   2.2  36.0  285   7  4  -3.1  -1.7
  8750   2.4  36.3  290  13  6  -0.1  -0.1 |   2.0  35.6  285   6  3  -4.5  -2.4
  8500   2.3  36.1  290  11  6  -1.1  -0.6 |   1.6  34.9  285   4  2  -4.7  -2.6
  8250   2.0  35.6  285  10  5  -7.1  -3.9 |   1.3  34.3  300   2  1  -2.2  -1.2
  8000   1.3  34.3  285   8  4  -9.7  -5.3 |   1.2  34.2  045   2  1  -1.1  -0.6
  7750   0.5  32.9  285   6  3 -14.8  -8.1 |   1.1  34.0  070   4  2   2.8   1.5
  7500  -0.6  30.9  280   3  2  -7.1  -3.9 |   1.6  34.9  070   5  3   8.7   4.8
  7250  -0.4  31.3  275   2  1   9.0   4.9 |   2.3  36.1  070   6  3  10.3   5.6
  7000   0.3  32.5  000   0  0   9.2   5.1 |   3.0  37.4  070   7  3   9.9   5.5
  6750   1.0  33.8  110   1  1   9.3   5.1 |   3.8  38.8  070   7  4  11.2   6.1
  6500   1.7  35.1  100   2  1  10.2   5.6 |   4.6  40.3  065   7  4  11.2   6.2
  6250   2.4  36.3  095   3  1  10.5   5.8 |   5.4  41.7  065   7  4  10.3   5.6
  6000   3.2  37.8  095   3  2  10.8   5.9 |   6.2  43.2  065   7  4  10.2   5.6
  5750   4.1  39.4  090   4  2  14.3   7.9 |   7.1  44.8  065   7  3  16.2   8.9
  5500   5.3  41.5  090   4  2  18.7  10.3 |   8.7  47.7  065   7  4  27.4  15.0

           05/20/2015 at 1500 MDT          |       05/20/2015 at 1800 MDT
                                           |
K index... +21.5  LI... +273.8             | K index... +21.6  LI... +274.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.8
                                           |
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 -59.1 -74.4  240  41 21   1.0   0.5 | -59.4 -74.9  245  38 20   0.8   0.5
 45000 -57.8 -72.0  250  57 30  -0.8  -0.4 | -58.4 -73.1  250  54 28  -0.9  -0.5
 40000 -59.1 -74.4  255  73 38  -0.6  -0.3 | -59.8 -75.6  260  74 38  -0.7  -0.4
 38000 -56.7 -70.1  255  74 38   5.6   3.1 | -57.4 -71.3  260  75 38   5.7   3.1
 36000 -53.3 -63.9  260  74 38   5.6   3.1 | -54.0 -65.2  260  72 37   5.7   3.1
 34000 -49.4 -56.9  260  71 37   8.2   4.5 | -49.9 -57.8  260  66 34   8.8   4.8
 32000 -44.5 -48.1  260  66 34   8.1   4.5 | -44.6 -48.3  260  55 28   8.7   4.8
 30000 -38.9 -38.0  260  59 30   8.6   4.7 | -38.8 -37.8  265  46 23   8.5   4.7
 29000 -36.4 -33.5  265  54 28   8.6   4.7 | -36.3 -33.3  265  44 22   8.5   4.7
 28000 -33.8 -28.8  265  50 26   8.5   4.7 | -33.8 -28.8  270  41 21   8.4   4.6
 27000 -31.5 -24.7  265  46 24   6.2   3.4 | -31.5 -24.7  270  40 21   6.5   3.6
 26000 -29.7 -21.5  270  43 22   6.3   3.4 | -29.6 -21.3  265  40 21   6.5   3.6
 25000 -27.8 -18.0  270  39 20   6.3   3.4 | -27.6 -17.7  265  40 20   6.5   3.6
 24000 -25.9 -14.6  270  36 18   5.7   3.1 | -25.7 -14.3  265  39 20   7.0   3.9
 23000 -24.2 -11.6  270  31 16   5.8   3.2 | -23.6 -10.5  265  36 19   7.0   3.8
 22000 -22.5  -8.5  270  26 13   5.8   3.2 | -21.5  -6.7  265  33 17   7.0   3.8
 21000 -20.6  -5.1  265  23 12   7.6   4.2 | -19.5  -3.1  265  31 16   6.9   3.8
 20000 -18.4  -1.1  270  24 12   7.5   4.1 | -17.4   0.7  265  30 15   7.0   3.8
 19500 -17.3   0.9  275  25 13   7.5   4.1 | -16.4   2.5  265  29 15   7.0   3.8
 19000 -16.2   2.8  275  25 13   7.6   4.2 | -15.4   4.3  265  28 15   7.1   3.9
 18500 -15.2   4.6  280  26 13   6.6   3.6 | -14.4   6.1  265  27 14   6.1   3.4
 18000 -14.2   6.4  275  26 14   6.7   3.7 | -13.5   7.7  265  25 13   6.2   3.4
 17500 -13.2   8.2  275  27 14   7.0   3.8 | -12.6   9.3  265  23 12   6.6   3.6
 17000 -12.2  10.0  275  27 14   7.2   4.0 | -11.6  11.1  265  21 11   6.8   3.7
 16500 -11.1  12.0  275  27 14   7.3   4.0 | -10.7  12.7  260  19 10   6.9   3.8
 16000 -10.0  14.0  275  26 13   7.5   4.1 |  -9.1  15.6  260  17  9   7.2   3.9
 15500  -8.4  16.9  275  23 12   7.4   4.0 |  -8.0  17.6  260  16  8   7.1   3.9
 15000  -7.4  18.7  275  22 11   7.0   3.8 |  -7.0  19.4  260  15  8   6.9   3.8
 14500  -6.4  20.5  270  20 10   7.0   3.9 |  -6.0  21.2  260  15  8   6.9   3.8
 14000  -5.3  22.5  270  19 10   7.1   3.9 |  -5.0  23.0  260  14  7   6.8   3.7
 13500  -4.3  24.3  265  17  9   7.1   3.9 |  -4.0  24.8  255  13  7   7.0   3.8
 13000  -3.3  26.1  260  16  8   7.4   4.0 |  -3.1  26.4  245  13  7   5.6   3.1
 12500  -2.2  28.0  255  15  8   7.6   4.1 |  -2.3  27.9  235  14  7   5.9   3.2
 12000  -1.3  29.7  245  15  7   5.3   2.9 |  -1.6  29.1  225  14  7   4.0   2.2
 11500  -0.5  31.1  240  14  7   5.8   3.2 |  -1.0  30.2  215  15  8   4.3   2.4
 11000   0.0  32.0  230  13  7   0.7   0.4 |  -0.6  30.9  210  15  8   1.0   0.6
 10500   0.1  32.2  230  12  6   1.0   0.5 |  -0.5  31.1  205  14  7   1.3   0.7
 10250   0.2  32.4  225  12  6  -0.1  -0.0 |  -0.4  31.3  205  13  7   0.1   0.1
 10000   0.1  32.2  225  11  6   0.8   0.4 |  -0.4  31.3  205  12  6   0.2   0.1
  9750   0.3  32.5  225   9  5   2.4   1.3 |  -0.3  31.5  195   9  5   1.5   0.8
  9500   0.4  32.7  225   7  4   2.1   1.2 |  -0.3  31.5  180   6  3   1.2   0.6
  9250   0.5  32.9  220   5  2   1.2   0.6 |  -0.1  31.8  145   4  2   4.2   2.3
  9000   0.6  33.1  185   2  1   1.7   0.9 |   0.3  32.5  125   4  2   7.1   3.9
  8750   0.8  33.4  095   3  1   3.9   2.1 |   0.9  33.6  105   5  2   7.8   4.3
  8500   1.1  34.0  075   6  3   5.7   3.1 |   1.4  34.5  085   6  3   8.0   4.4
  8250   1.6  34.9  070   7  4   8.5   4.7 |   2.0  35.6  070   7  4   7.0   3.9
  8000   2.3  36.1  065   8  4   9.6   5.3 |   2.5  36.5  065   8  4   6.9   3.8
  7750   3.0  37.4  065   9  5   9.7   5.3 |   3.0  37.4  060   8  4   9.0   5.0
  7500   3.7  38.7  065   9  5  10.1   5.5 |   3.8  38.8  060   9  4  10.2   5.6
  7250   4.5  40.1  060   9  5  10.0   5.5 |   4.5  40.1  060   8  4   9.6   5.3
  7000   5.2  41.4  060   9  5  10.0   5.5 |   5.2  41.4  055   8  4   9.8   5.4
  6750   6.0  42.8  060   9  5  10.3   5.6 |   5.9  42.6  055   8  4   9.6   5.3
  6500   6.8  44.2  060   9  5  10.4   5.7 |   6.7  44.1  055   8  4   9.7   5.3
  6250   7.5  45.5  060   9  5   9.9   5.4 |   7.4  45.3  055   8  4   9.6   5.3
  6000   8.3  46.9  060   9  5  11.1   6.1 |   8.1  46.6  055   8  4  10.3   5.6
  5750   9.3  48.7  060   9  4  17.3   9.5 |   8.9  48.0  050   8  4  12.1   6.6
  5500  10.8  51.4  055   9  5  24.0  13.2 |   9.8  49.6  050   8  4  13.0   7.1
________________________________________________________________________________

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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