Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 021250
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0650 MDT Saturday, May 2, 2015

This forecast is for Saturday, May 2, 2015:

If the trigger temperature of 70.3 F/21.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1258 ft/min (6.4 m/s)
   Maximum height of thermals.................. 18510 ft MSL (13225 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1045 MDT
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................. 10151 ft MSL (4866 ft AGL)
Thermal soaring outlook for Sunday 05/03....... 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....................... 22303 ft MSL (17018 ft AGL)
Wave soaring outlook for Sunday 05/03.......... Poor

Remarks...

Sunrise/Sunset.................... 05:59:07 / 19:53:37 MDT
Total possible sunshine........... 13 hr 54 min 29 sec (834 min 29 sec)
Altitude of sun at 12:56:33 MDT... 65.68 degrees

Upper air data from rawinsonde observation taken on 05/02/2015 at 0600 MDT

Freezing level.................. 13036 ft MSL (7751 ft AGL)
Convective condensation level... 16035 ft MSL (10750 ft AGL)
Lifted condensation level....... 16822 ft MSL (11536 ft AGL)
Lifted index.................... -1.8
K index......................... +14.9

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  -60.9 -77.6   265   26   13   2.9   1.6   97.5 207.5    41.2      M    M
 45000  -61.7 -79.1   265   38   20  -1.9  -1.0   71.4 160.4    28.1      M    M
 40000  -64.7 -84.5   260   39   20   8.7   4.8   43.6 110.4    11.9      M    M
 38000  -62.4 -80.3   270   42   22   7.3   4.0   38.3 100.9     8.6      M    M
 36000  -58.0 -72.4   265   44   23   8.6   4.7   36.1  97.0     7.4      M    M
 34000  -52.2 -62.0   260   43   22   7.8   4.3   35.0  95.1     6.8      M    M
 32000  -46.6 -51.9   265   40   20   9.0   4.9   34.6  94.3     6.6      M    M
 30000  -41.4 -42.5   270   38   20   6.5   3.6   33.8  92.8     6.2      M    M
 29000  -39.3 -38.7   275   37   19   7.6   4.2   32.7  90.9     5.5      M    M
 28000  -36.9 -34.4   275   36   19   8.6   4.7   32.1  89.7     5.0      M    M
 27000  -34.4 -29.9   280   35   18   7.3   4.0   31.5  88.7     4.6      M    M
 26000  -31.8 -25.2   280   35   18   9.2   5.0   31.0  87.9     4.3      M    M
 25000  -29.1 -20.4   285   34   18   9.0   4.9   30.9  87.6     4.2      M    M
 24000  -26.5 -15.7   285   33   17  10.1   5.6   30.5  86.8     3.9      M    M
 23000  -24.2 -11.6   280   35   18   7.4   4.1   29.6  85.3     3.3      M    M
 22000  -21.9  -7.4   285   33   17   8.1   4.4   28.8  83.9     2.6      M    M
 21000  -19.5  -3.1   290   31   16   6.8   3.8   28.2  82.7     2.1      M    M
 20000  -17.6   0.3   300   29   15   6.7   3.7   27.0  80.7     1.1      M    M
 19500  -16.6   2.1   300   28   14   6.7   3.7   26.5  79.7     0.7      M    M
 19000  -15.6   3.9   305   27   14   7.5   4.1   25.9  78.7     0.2      M    M
 18500  -14.3   6.3   305   27   14   8.8   4.8   25.7  78.3     0.0      M    M
 18000  -13.0   8.6   305   27   14   9.0   4.9   25.6  78.1    -0.1   1213  6.2
 17500  -11.7  10.9   305   27   14   6.8   3.7   25.3  77.6    -0.3   1161  5.9
 17000  -10.4  13.3   300   26   14   6.1   3.4   24.4  76.0    -1.2   1100  5.6
 16500   -9.3  15.3   300   26   13   9.3   5.1   24.1  75.4    -1.6   1053  5.3
 16000   -8.0  17.6   300   26   13   8.6   4.7   24.0  75.3    -1.7    998  5.1
 15500   -6.6  20.1   305   25   13   9.7   5.3   23.9  75.0    -1.8    942  4.8
 15000   -5.2  22.6   310   24   12   9.4   5.1   23.9  74.9    -1.9    884  4.5
 14500   -3.8  25.2   310   23   12   9.1   5.0   23.8  74.8    -1.9    828  4.2
 14000   -2.4  27.7   315   23   12   9.1   5.0   23.7  74.7    -2.0    772  3.9
 13500   -1.1  30.0   315   22   12   9.1   5.0   23.6  74.5    -2.2    717  3.6
 13000    0.3  32.5   310   22   11   9.1   5.0   23.5  74.3    -2.3    661  3.4
 12500    1.7  35.1   310   21   11   9.1   5.0   23.4  74.2    -2.3    605  3.1
 12000    3.0  37.4   310   21   11   9.1   5.0   23.4  74.1    -2.4    549  2.8
 11500    4.4  39.9   310   22   11   9.2   5.0   23.2  73.8    -2.6    494  2.5
 11000    5.7  42.3   310   23   12   9.2   5.0   23.1  73.7    -2.7    438  2.2
 10500    7.1  44.8   305   20   10   9.8   5.4   23.0  73.4    -2.8    382  1.9
 10250    7.8  46.0   305   19   10   6.8   3.7   23.0  73.3    -2.9    354  1.8
 10000    8.1  46.6   305   18    9   4.5   2.5   22.6  72.6    -3.3    337  1.7
  9750    8.5  47.3   300   17    9   5.8   3.2   22.2  72.0    -3.7    319  1.6
  9500    8.9  48.0   300   15    8   7.1   3.9   22.0  71.5    -4.0    298  1.5
  9250    9.5  49.1   300   14    7   8.4   4.6   21.8  71.3    -4.1    273  1.4
  9000   10.1  50.2   295   13    7   8.1   4.4   21.7  71.1    -4.2    248  1.3
  8750   10.7  51.3   295   11    6   8.2   4.5   21.6  70.9    -4.4    222  1.1
  8500   11.3  52.3   295   10    5   8.1   4.5   21.5  70.6    -4.5    197  1.0
  8250   11.9  53.4   300    8    4   8.1   4.5   21.3  70.4    -4.7    171  0.9
  8000   12.5  54.5   300    7    4   8.1   4.5   21.2  70.2    -4.8    146  0.7
  7750   13.1  55.6   300    6    3   8.1   4.5   21.1  70.0    -4.9    120  0.6
  7500   13.7  56.7   300    6    3   8.2   4.5   21.0  69.7    -5.1     95  0.5
  7250   14.3  57.7   295    5    2   8.1   4.4   20.8  69.5    -5.2     69  0.4
  7000   14.9  58.8   295    4    2   5.3   2.9   20.7  69.2    -5.4     46  0.2
  6750   15.1  59.2   260    5    2   3.3   1.8   20.2  68.3    -5.9     31  0.2
  6500   15.4  59.7   240    7    3   4.0   2.2   19.7  67.5    -6.4     16  0.1
  6250   15.6  60.1   225    9    5   0.7   0.4   19.2  66.6    -7.0      3  0.0
  6000   15.2  59.4   220   12    6  -7.5  -4.1   18.2  64.8    -8.1      6  0.0
  5750   14.4  57.9   215   10    5  -8.7  -4.8   16.8  62.2    -9.6     22  0.1
  5500   13.6  56.5   205    7    4 -14.4  -7.9   15.3  59.6   -11.2     38  0.2

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

           05/02/2015 at 0900 MDT          |       05/02/2015 at 1200 MDT
                                           |
K index... +16.2  LI... +272.3             | K index... +19.7  LI... +271.6
CAPE... +80.0  CIN... -55.4                | CAPE... +268.6  CIN... -35.2
                                           |
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  280  23 12  -0.5  -0.3 | -60.9 -77.6  270  23 12  -0.6  -0.3
 45000 -61.6 -78.9  285  31 16  -0.9  -0.5 | -61.8 -79.2  285  31 16  -0.7  -0.4
 40000 -63.1 -81.6  275  37 19  -1.0  -0.6 | -62.8 -81.0  270  36 19  -0.8  -0.4
 38000 -60.8 -77.4  270  39 20   6.5   3.6 | -60.7 -77.3  265  39 20   6.0   3.3
 36000 -56.4 -69.5  265  42 22   6.5   3.6 | -56.6 -69.9  270  44 22   6.0   3.3
 34000 -51.9 -61.4  265  43 22   8.5   4.7 | -52.3 -62.1  270  45 23   8.8   4.8
 32000 -46.8 -52.2  265  41 21   8.5   4.7 | -47.0 -52.6  265  43 22   8.8   4.8
 30000 -41.8 -43.2  270  38 19   8.2   4.5 | -41.8 -43.2  265  39 20   8.4   4.6
 29000 -39.3 -38.7  270  35 18   8.2   4.5 | -39.3 -38.7  265  36 19   8.4   4.6
 28000 -36.9 -34.4  270  32 16   8.2   4.5 | -36.8 -34.2  265  34 17   8.4   4.6
 27000 -34.4 -29.9  275  30 15   8.4   4.6 | -34.3 -29.7  270  31 16   8.4   4.6
 26000 -31.9 -25.4  280  29 15   8.4   4.6 | -31.7 -25.1  270  30 15   8.4   4.6
 25000 -29.4 -20.9  280  28 15   8.4   4.6 | -29.2 -20.6  275  29 15   8.4   4.6
 24000 -26.9 -16.4  285  27 14   7.4   4.0 | -26.7 -16.1  275  27 14   8.1   4.5
 23000 -24.7 -12.5  285  26 14   7.5   4.1 | -24.3 -11.7  280  26 14   8.2   4.5
 22000 -22.5  -8.5  290  25 13   7.5   4.1 | -21.8  -7.2  280  26 13   8.1   4.5
 21000 -20.2  -4.4  295  25 13   7.8   4.3 | -19.5  -3.1  280  25 13   7.1   3.9
 20000 -17.9  -0.2  295  26 13   7.8   4.3 | -17.4   0.7  285  26 13   7.2   3.9
 19500 -16.7   1.9  300  26 13   7.9   4.3 | -16.3   2.7  285  26 13   7.2   3.9
 19000 -15.6   3.9  300  26 13   7.8   4.3 | -15.3   4.5  285  26 14   7.1   3.9
 18500 -14.4   6.1  300  27 14   8.5   4.7 | -14.1   6.6  285  27 14   8.9   4.9
 18000 -12.5   9.5  300  27 14   8.4   4.6 | -12.1  10.2  285  29 15   8.8   4.8
 17500 -11.2  11.8  300  27 14   8.2   4.5 | -10.8  12.6  285  29 15   8.5   4.7
 17000 -10.0  14.0  300  27 14   8.3   4.5 |  -9.6  14.7  285  29 15   8.5   4.7
 16500  -8.7  16.3  300  26 13   8.4   4.6 |  -8.3  17.1  285  29 15   8.6   4.7
 16000  -7.5  18.5  300  25 13   8.4   4.6 |  -7.0  19.4  285  29 15   8.7   4.8
 15500  -6.3  20.7  300  24 12   8.6   4.7 |  -5.8  21.6  285  28 15   8.6   4.7
 15000  -5.0  23.0  300  23 12   8.8   4.8 |  -4.5  23.9  285  27 14   8.5   4.7
 14500  -3.7  25.3  300  22 11   8.8   4.8 |  -3.2  26.2  285  26 13   8.5   4.7
 14000  -2.4  27.7  300  21 11   8.4   4.6 |  -2.0  28.4  285  24 12   8.5   4.7
 13500  -1.1  30.0  300  19 10   8.5   4.7 |  -0.7  30.7  285  22 11   8.6   4.7
 13000   0.1  32.2  305  17  9   8.0   4.4 |   0.5  32.9  285  20 10   8.0   4.4
 12500   1.3  34.3  305  16  8   8.0   4.4 |   1.7  35.1  285  17  9   8.0   4.4
 12000   2.6  36.7  310  14  7   8.7   4.8 |   2.9  37.2  290  15  8   8.4   4.6
 11500   3.9  39.0  310  12  6   8.6   4.7 |   4.1  39.4  290  13  7   8.6   4.7
 11000   5.2  41.4  310  11  6   9.5   5.2 |   5.3  41.5  295  11  6   7.1   3.9
 10500   6.6  43.9  310  11  6  10.5   5.8 |   6.3  43.3  295  10  5   6.0   3.3
 10250   7.3  45.1  310  11  6   5.6   3.1 |   6.9  44.4  300   9  5  11.1   6.1
 10000   7.6  45.7  310  11  6   6.3   3.5 |   7.9  46.2  300   8  4  11.9   6.5
  9750   8.3  46.9  310  11  6  11.5   6.3 |   8.5  47.3  300   7  4   7.5   4.1
  9500   9.1  48.4  310  11  6  10.7   5.8 |   9.1  48.4  300   6  3   8.6   4.7
  9250   9.9  49.8  310  11  6   9.1   5.0 |   9.7  49.5  305   5  3   8.6   4.7
  9000  10.5  50.9  305  11  6   8.5   4.6 |  10.4  50.7  305   5  3   9.7   5.3
  8750  11.2  52.2  305  11  6  10.0   5.5 |  11.1  52.0  305   5  2  10.1   5.5
  8500  11.8  53.2  305  11  6   9.6   5.3 |  11.8  53.2  305   5  2  10.0   5.5
  8250  12.5  54.5  305  12  6   9.2   5.1 |  12.6  54.7  305   4  2  10.1   5.5
  8000  13.2  55.8  305  12  6   8.6   4.7 |  13.3  55.9  305   4  2  10.1   5.5
  7750  13.8  56.8  300  12  6   8.4   4.6 |  14.1  57.4  305   4  2  10.0   5.5
  7500  14.4  57.9  300  13  6   8.2   4.5 |  14.8  58.6  305   4  2  10.0   5.5
  7250  15.0  59.0  300  13  7   8.2   4.5 |  15.6  60.1  305   4  2  10.2   5.6
  7000  15.6  60.1  295  13  6   7.8   4.3 |  16.3  61.3  305   4  2  10.2   5.6
  6750  16.2  61.2  295  12  6   8.5   4.6 |  17.1  62.8  305   4  2   9.2   5.1
  6500  16.8  62.2  295  12  6   4.0   2.2 |  17.8  64.0  305   4  2   9.6   5.3
  6250  16.8  62.2  290  10  5  -0.6  -0.3 |  18.5  65.3  305   4  2  10.8   5.9
  6000  16.7  62.1  285   9  4   0.4   0.2 |  19.4  66.9  305   4  2  10.3   5.6
  5750  16.6  61.9  280   7  4  -2.9  -1.6 |  20.2  68.4  305   4  2  12.3   6.7
  5500  16.2  61.2  260   6  3  -4.7  -2.6 |  21.3  70.3  305   4  2  20.0  11.0

           05/02/2015 at 1500 MDT          |       05/02/2015 at 1800 MDT
                                           |
K index... +25.0  LI... +271.5             | K index... +21.1  LI... +271.5
CAPE... +376.0  CIN... -11.0               | CAPE... +316.9  CIN... -61.3
                                           |
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 -61.3 -78.3  270  28 15  -0.2  -0.1 | -62.0 -79.6  275  28 15   0.3   0.2
 45000 -61.6 -78.9  275  33 17  -1.1  -0.6 | -61.7 -79.1  270  33 17  -1.5  -0.8
 40000 -63.8 -82.8  260  43 22  -1.2  -0.6 | -64.1 -83.4  260  40 20  -1.6  -0.9
 38000 -61.0 -77.8  260  44 23   7.0   3.8 | -61.5 -78.7  255  39 20   7.4   4.1
 36000 -56.8 -70.2  260  45 23   7.0   3.8 | -56.5 -69.7  250  36 19   7.4   4.1
 34000 -52.2 -62.0  260  43 22   9.0   4.9 | -51.6 -60.9  250  35 18   9.3   5.1
 32000 -46.8 -52.2  260  40 21   9.0   4.9 | -46.0 -50.8  245  35 18   9.3   5.1
 30000 -41.5 -42.7  260  37 19   8.8   4.9 | -40.5 -40.9  250  35 18   8.8   4.8
 29000 -38.8 -37.8  260  36 18   8.9   4.9 | -37.9 -36.2  255  34 18   8.8   4.8
 28000 -35.5 -31.9  260  34 18   8.9   4.9 | -35.3 -31.5  255  34 18   8.8   4.8
 27000 -33.0 -27.4  265  33 17   8.2   4.5 | -32.7 -26.9  260  34 17   8.1   4.4
 26000 -30.6 -23.1  265  30 16   8.2   4.5 | -30.3 -22.5  260  32 17   8.1   4.4
 25000 -28.1 -18.6  270  28 15   8.2   4.5 | -27.9 -18.2  265  31 16   8.1   4.5
 24000 -25.7 -14.3  275  27 14   7.7   4.2 | -25.5 -13.9  270  30 15   7.6   4.2
 23000 -23.5 -10.3  280  28 14   7.8   4.3 | -23.2  -9.8  270  28 15   7.7   4.2
 22000 -21.2  -6.2  280  28 14   7.8   4.3 | -20.9  -5.6  275  27 14   7.7   4.2
 21000 -18.9  -2.0  280  28 15   7.8   4.3 | -18.7  -1.7  280  26 14   7.4   4.1
 20000 -16.5   2.3  280  29 15   7.9   4.3 | -16.5   2.3  285  26 13   7.5   4.1
 19500 -15.4   4.3  280  29 15   7.9   4.3 | -15.4   4.3  285  26 13   7.5   4.1
 19000 -14.2   6.4  280  30 15   7.9   4.3 | -14.3   6.3  290  26 13   7.4   4.1
 18500 -13.1   8.4  280  29 15   7.8   4.3 | -13.1   8.4  290  26 13   8.3   4.5
 18000 -11.9  10.6  285  28 14   7.9   4.3 | -11.3  11.7  295  25 13   8.3   4.6
 17500 -10.8  12.6  285  27 14   7.6   4.2 | -10.1  13.8  300  24 12   7.5   4.1
 17000  -9.7  14.5  285  26 13   7.5   4.1 |  -9.0  15.8  300  24 12   7.6   4.1
 16500  -8.6  16.5  285  24 12   7.6   4.1 |  -7.9  17.8  305  23 12   8.0   4.4
 16000  -7.5  18.5  285  23 12   7.9   4.3 |  -6.6  20.1  305  22 12   8.2   4.5
 15500  -6.3  20.7  290  21 11   7.9   4.4 |  -5.4  22.3  310  21 11   8.3   4.6
 15000  -4.6  23.7  290  19 10   7.7   4.2 |  -4.2  24.4  310  20 10   8.6   4.7
 14500  -3.5  25.7  290  17  9   7.8   4.3 |  -2.9  26.8  310  17  9   8.6   4.7
 14000  -2.3  27.9  290  15  8   8.2   4.5 |  -1.6  29.1  315  15  8   8.7   4.8
 13500  -1.1  30.0  285  13  7   8.1   4.5 |  -0.3  31.5  315  12  6   8.7   4.8
 13000   0.2  32.4  280  12  6   8.8   4.8 |   0.9  33.6  320   9  5   8.4   4.6
 12500   1.5  34.7  280  10  5   8.7   4.7 |   2.2  36.0  315   7  3   8.4   4.6
 12000   2.8  37.0  275   9  5   9.3   5.1 |   3.4  38.1  310   4  2   7.8   4.3
 11500   4.2  39.6  270   8  4   9.3   5.1 |   4.5  40.1  265   2  1   7.8   4.3
 11000   5.5  41.9  265   6  3   8.5   4.7 |   5.7  42.3  215   3  2   7.1   3.9
 10500   6.7  44.1  265   5  3   7.8   4.3 |   6.7  44.1  200   5  3   6.2   3.4
 10250   7.4  45.3  260   5  2  11.4   6.3 |   7.2  45.0  200   6  3  10.4   5.7
 10000   8.3  46.9  260   4  2  12.1   6.6 |   8.2  46.8  200   8  4  11.1   6.1
  9750   9.0  48.2  260   4  2   8.9   4.9 |   8.8  47.8  200   9  4   7.4   4.1
  9500   9.8  49.6  260   3  2   9.9   5.4 |   9.4  48.9  200  10  5   8.5   4.7
  9250  10.5  50.9  260   3  1   9.2   5.0 |  10.0  50.0  200  11  5   7.8   4.3
  9000  11.1  52.0  260   2  1   9.2   5.1 |  10.6  51.1  200  12  6   8.0   4.4
  8750  11.8  53.2  260   2  1   9.8   5.4 |  11.2  52.2  200  12  6   8.6   4.7
  8500  12.5  54.5  260   2  1   9.3   5.1 |  11.8  53.2  200  13  7   8.3   4.5
  8250  13.2  55.8  265   2  1  11.1   6.1 |  12.4  54.3  205  14  7   9.1   5.0
  8000  14.1  57.4  265   2  1  11.0   6.0 |  13.1  55.6  205  14  7   9.5   5.2
  7750  14.8  58.6  270   2  1   8.9   4.9 |  13.8  56.8  205  15  8   8.8   4.9
  7500  15.5  59.9  275   2  1   9.2   5.1 |  14.4  57.9  205  15  8   8.8   4.8
  7250  16.2  61.2  275   2  1  10.3   5.6 |  15.1  59.2  205  16  8   9.6   5.2
  7000  17.0  62.6  275   2  1  10.7   5.9 |  15.8  60.4  205  16  8  10.0   5.5
  6750  17.8  64.0  275   2  1   9.7   5.3 |  16.5  61.7  205  16  8   8.9   4.9
  6500  18.5  65.3  280   2  1  10.0   5.5 |  17.2  63.0  205  16  8   8.8   4.8
  6250  19.3  66.7  280   2  1  11.0   6.0 |  17.8  64.0  205  16  8   9.4   5.1
  6000  20.1  68.2  280   2  1  10.8   5.9 |  18.5  65.3  205  15  8   9.7   5.3
  5750  20.9  69.6  280   2  1  10.8   5.9 |  19.1  66.4  205  15  8   8.1   4.4
  5500  21.8  71.2  285   2  1  15.9   8.7 |  19.5  67.1  205  13  7   5.4   3.0
________________________________________________________________________________

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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