Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 021315
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0715 MDT Tuesday, June 2, 2015

This forecast is for Tuesday, June 2, 2015:

If the trigger temperature of 83.1 F/28.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1481 ft/min (7.5 m/s)
   Maximum height of thermals.................. 19996 ft MSL (14711 ft AGL)

Forecast maximum temperature................... 88.0 F/31.6 C
Time of trigger temperature.................... 1130 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................. 8648 ft MSL (3363 ft AGL)
Thermal soaring outlook for Wednesday 06/03.... Poor

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....................... 20014 ft MSL (14729 ft AGL)
Wave soaring outlook for Wednesday 06/03....... Poor

Remarks...

Sunrise/Sunset.................... 05:33:19 / 20:21:26 MDT
Total possible sunshine........... 14 hr 48 min 7 sec (888 min 7 sec)
Altitude of sun at 12:57:34 MDT... 72.42 degrees

Upper air data from rawinsonde observation taken on 06/02/2015 at 0600 MDT

Freezing level.................. 15029 ft MSL (9744 ft AGL)
Convective condensation level... 16659 ft MSL (11374 ft AGL)
Lifted condensation level....... 17435 ft MSL (12150 ft AGL)
Lifted index.................... -1.2
K index......................... +7.1

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  -64.5 -84.1   290   27   14   2.9   1.6   87.2 189.0    32.5      M    M
 45000  -61.9 -79.4   260   25   13   3.5   1.9   67.3 153.2    22.5      M    M
 40000  -56.4 -69.5   265   30   15   3.1   1.7   52.2 125.9    14.1      M    M
 38000  -55.9 -68.6   265   43   22  10.1   5.5   44.2 111.5     9.0      M    M
 36000  -50.7 -59.3   260   41   21   8.6   4.7   43.3 109.9     8.6      M    M
 34000  -45.3 -49.5   260   40   21   8.7   4.8   42.6 108.6     8.3      M    M
 32000  -40.1 -40.2   255   39   20   8.8   4.8   41.7 107.1     7.8      M    M
 30000  -35.3 -31.5   245   36   19   7.0   3.8   40.5 104.9     7.1      M    M
 29000  -32.8 -27.0   250   34   17   8.5   4.7   39.7 103.5     6.6      M    M
 28000  -30.3 -22.5   255   31   16   8.5   4.7   39.2 102.6     6.3      M    M
 27000  -27.1 -16.8   265   29   15   8.5   4.7   38.7 101.7     6.0      M    M
 26000  -24.6 -12.3   270   28   14   8.5   4.7   38.4 101.2     5.8      M    M
 25000  -22.0  -7.6   265   26   13   8.5   4.7   37.9 100.2     5.4      M    M
 24000  -19.5  -3.1   265   26   13   8.5   4.7   37.4  99.3     5.1      M    M
 23000  -16.9   1.6   260   24   12   8.5   4.6   37.0  98.6     4.8      M    M
 22000  -14.7   5.5   270   21   11   4.4   2.4   36.1  97.0     4.2      M    M
 21000  -14.2   6.4   280   18    9   8.6   4.7   33.3  91.9     1.8      M    M
 20000  -13.0   8.6   270   25   13   7.7   4.2   31.3  88.3     0.0      M    M
 19500  -12.1  10.2   270   24   12   6.3   3.4   30.7  87.2    -0.5   1439  7.3
 19000  -11.4  11.5   265   24   12   6.9   3.8   29.9  85.8    -1.3   1403  7.1
 18500   -9.9  14.2   265   23   12   9.8   5.4   29.9  85.8    -1.3   1345  6.8
 18000   -8.6  16.5   270   22   12   9.4   5.2   29.8  85.6    -1.4   1289  6.5
 17500   -7.2  19.0   270   22   11   9.4   5.2   29.8  85.6    -1.5   1233  6.3
 17000   -5.8  21.6   270   21   11   9.3   5.1   29.7  85.5    -1.6   1177  6.0
 16500   -4.4  24.1   275   20   10   9.3   5.1   29.6  85.3    -1.6   1121  5.7
 16000   -3.0  26.6   275   19   10   9.3   5.1   29.6  85.2    -1.7   1064  5.4
 15500   -1.6  29.1   275   19   10   9.3   5.1   29.5  85.1    -1.7   1007  5.1
 15000   -0.2  31.6   275   19   10   9.3   5.1   29.4  84.9    -1.8    950  4.8
 14500    1.2  34.2   280   19   10   9.5   5.2   29.4  84.8    -1.9    894  4.5
 14000    2.6  36.7   280   19   10   9.5   5.2   29.3  84.8    -1.9    837  4.3
 13500    4.7  40.5   280   18    9   9.5   5.2   29.3  84.7    -2.0    752  3.8
 13000    6.1  43.0   280   17    9   9.5   5.2   29.2  84.6    -2.1    696  3.5
 12500    7.5  45.5   280   17    9   9.5   5.2   29.2  84.6    -2.1    639  3.2
 12000    8.9  48.0   280   16    8   9.5   5.2   29.2  84.5    -2.2    582  3.0
 11500   10.3  50.5   275   15    8   9.5   5.2   29.1  84.4    -2.3    526  2.7
 11000   11.7  53.1   270   14    7   9.5   5.2   29.1  84.3    -2.3    469  2.4
 10500   13.1  55.6   265   12    6   9.5   5.2   29.0  84.2    -2.4    412  2.1
 10250   13.8  56.8   260   11    6   9.6   5.3   29.0  84.2    -2.5    384  2.0
 10000   14.5  58.1   250   10    5   9.7   5.3   29.0  84.2    -2.5    356  1.8
  9750   15.2  59.4   250   10    5   9.8   5.4   29.0  84.2    -2.6    327  1.7
  9500   15.9  60.6   250   10    5   9.7   5.3   29.0  84.2    -2.6    299  1.5
  9250   16.6  61.9   250   10    5  10.1   5.5   29.0  84.2    -2.6    270  1.4
  9000   17.3  63.1   250   10    5   8.7   4.8   29.0  84.2    -2.6    242  1.2
  8750   17.8  64.0   245   14    7   5.7   3.1   28.8  83.8    -2.9    219  1.1
  8500   18.1  64.6   245   17    9   4.4   2.4   28.4  83.1    -3.3    202  1.0
  8250   18.4  65.1   240   20   10   6.0   3.3   28.0  82.5    -3.7    185  0.9
  8000   18.8  65.8   240   23   12   1.2   0.6   27.7  81.8    -4.1    168  0.9
  7750   18.4  65.1   240   21   11  -6.3  -3.4   26.7  80.0    -5.2    170  0.9
  7500   18.0  64.4   240   20   10  -0.5  -0.3   25.5  78.0    -6.3    175  0.9
  7250   18.2  64.8   235   18   10   4.1   2.3   25.1  77.1    -6.8    161  0.8
  7000   18.5  65.3   235   17    9   5.6   3.1   24.6  76.3    -7.3    146  0.7
  6750   18.8  65.8   235   14    7  -3.2  -1.7   24.2  75.5    -7.8    131  0.7
  6500   17.8  64.0   235   12    6 -14.5  -7.9   22.6  72.7    -9.5    151  0.8
  6250   16.7  62.1   235    9    5 -12.7  -7.0   20.8  69.5   -11.3    177  0.9
  6000   15.6  60.1   240    6    3 -17.0  -9.3   19.0  66.3   -13.3    204  1.0
  5750   14.1  57.4   255    5    3 -11.7  -6.4   17.0  62.7   -15.5    240  1.2
  5500   13.8  56.8   275    4    2   5.2   2.8   16.1  61.0   -16.6    243  1.2

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

           06/02/2015 at 0900 MDT          |       06/02/2015 at 1200 MDT
                                           |
K index... +5.9  LI... +274.5              | K index... +2.7  LI... +274.7
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -1.6
                                           |
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 -63.1 -81.6  315  16  8   1.1   0.6 | -63.0 -81.4  290  12  6   1.4   0.8
 45000 -61.0 -77.8  305  19 10   2.5   1.4 | -60.6 -77.1  270  18  9   2.5   1.4
 40000 -56.9 -70.4  285  37 19   5.6   3.1 | -56.4 -69.5  280  36 19   5.5   3.0
 38000 -53.3 -63.9  275  33 17   6.0   3.3 | -52.9 -63.2  275  32 16   5.9   3.2
 36000 -49.7 -57.5  265  30 16   6.0   3.3 | -49.4 -56.9  265  29 15   5.9   3.3
 34000 -45.0 -49.0  265  27 14   8.8   4.8 | -44.8 -48.6  255  27 14   8.4   4.6
 32000 -39.7 -39.5  270  24 12   8.9   4.9 | -39.8 -39.6  255  27 14   8.4   4.6
 30000 -34.8 -30.6  270  23 12   7.9   4.3 | -35.2 -31.4  250  26 14   7.2   3.9
 29000 -32.4 -26.3  265  22 11   7.9   4.3 | -32.5 -26.5  245  26 13   7.2   3.9
 28000 -29.5 -21.1  260  22 11   7.9   4.3 | -30.4 -22.7  245  25 13   7.4   4.1
 27000 -27.1 -16.8  265  22 11   7.8   4.3 | -28.0 -18.4  250  24 12   8.1   4.4
 26000 -24.8 -12.6  265  21 11   7.8   4.3 | -25.6 -14.1  250  23 12   8.1   4.4
 25000 -22.5  -8.5  270  21 11   7.8   4.3 | -23.2  -9.8  255  21 11   8.1   4.4
 24000 -20.2  -4.4  270  20 10   7.3   4.0 | -20.7  -5.3  255  20 10   8.1   4.5
 23000 -18.0  -0.4  270  19 10   7.3   4.0 | -18.3  -0.9  255  19 10   8.1   4.5
 22000 -15.8   3.6  265  18  9   7.4   4.1 | -15.8   3.6  255  18  9   8.2   4.5
 21000 -13.9   7.0  265  18  9   6.4   3.5 | -13.6   7.5  255  17  9   7.2   4.0
 20000 -11.9  10.6  265  18  9   6.5   3.5 | -11.4  11.5  255  17  9   7.3   4.0
 19500 -11.0  12.2  265  18  9   6.5   3.5 | -10.4  13.3  255  17  9   7.2   4.0
 19000 -10.0  14.0  265  18  9   7.7   4.2 |  -9.3  15.3  255  16  8   7.7   4.2
 18500  -8.8  16.2  265  18  9   8.3   4.5 |  -8.1  17.4  255  17  9   8.0   4.4
 18000  -7.5  18.5  265  18  9   8.3   4.6 |  -6.9  19.6  260  18  9   8.0   4.4
 17500  -6.3  20.7  265  19 10   8.0   4.4 |  -5.7  21.7  260  18  9   7.9   4.4
 17000  -5.2  22.6  265  19 10   8.0   4.4 |  -4.5  23.9  260  18  9   8.0   4.4
 16500  -4.0  24.8  265  19 10   8.6   4.7 |  -3.4  25.9  260  18  9   7.8   4.3
 16000  -2.7  27.1  260  19 10   8.8   4.8 |  -2.2  28.0  260  18  9   7.8   4.3
 15500  -1.4  29.5  260  19 10   8.7   4.8 |  -0.5  31.1  255  17  9   8.0   4.4
 15000   0.5  32.9  255  19 10   8.6   4.7 |   0.7  33.3  250  16  8   8.0   4.4
 14500   1.8  35.2  255  19 10   9.3   5.1 |   1.9  35.4  245  14  7   8.6   4.7
 14000   3.2  37.8  255  18  9   9.8   5.4 |   3.2  37.8  245  14  7   8.9   4.9
 13500   4.7  40.5  250  17  9   9.7   5.3 |   4.5  40.1  240  14  7   9.0   4.9
 13000   6.1  43.0  250  16  8   9.3   5.1 |   5.8  42.4  245  13  7   9.0   4.9
 12500   7.4  45.3  245  15  8   9.3   5.1 |   7.1  44.8  245  12  6   9.0   4.9
 12000   8.8  47.8  245  14  7   9.2   5.0 |   8.4  47.1  250  12  6   8.6   4.7
 11500  10.2  50.4  245  13  7   9.2   5.1 |   9.7  49.5  250  11  6   8.7   4.8
 11000  11.3  52.3  245  12  6   7.1   3.9 |  10.8  51.4  255  10  5   7.5   4.1
 10500  12.4  54.3  250  11  6  10.2   5.6 |  11.9  53.4  265  10  5  10.6   5.8
 10250  13.3  55.9  260  11  6  11.2   6.1 |  12.8  55.0  270   9  5  11.6   6.4
 10000  14.0  57.2  265  12  6   8.0   4.4 |  13.5  56.3  270   9  5   8.3   4.6
  9750  14.6  58.3  270  13  7   8.9   4.9 |  14.1  57.4  275   9  5   9.3   5.1
  9500  15.2  59.4  270  14  7   8.6   4.7 |  14.8  58.6  275   9  5   8.9   4.9
  9250  15.9  60.6  275  15  8   8.0   4.4 |  15.4  59.7  275   9  5   8.5   4.7
  9000  16.4  61.5  275  17  9   8.1   4.4 |  16.0  60.8  280   9  5   9.0   5.0
  8750  17.1  62.8  280  18  9   8.7   4.8 |  16.7  62.1  280   9  5   9.6   5.2
  8500  17.7  63.9  280  20 10   8.4   4.6 |  17.4  63.3  280   9  5   9.6   5.2
  8250  18.3  64.9  280  22 11   7.0   3.9 |  18.1  64.6  285   9  5  10.5   5.8
  8000  18.8  65.8  285  23 12   6.7   3.7 |  18.9  66.0  285   9  5  10.4   5.7
  7750  19.3  66.7  285  24 12   7.4   4.0 |  19.7  67.5  285   9  5   9.7   5.3
  7500  19.9  67.8  285  24 13   7.5   4.1 |  20.4  68.7  285   9  5   9.9   5.4
  7250  20.4  68.7  285  25 13   8.1   4.4 |  21.1  70.0  285   9  5  10.1   5.5
  7000  21.0  69.8  285  24 13   8.0   4.4 |  21.9  71.4  285   9  4  10.0   5.5
  6750  21.6  70.9  285  24 12   9.3   5.1 |  22.6  72.7  285   9  4   9.4   5.1
  6500  22.3  72.1  285  23 12   5.0   2.8 |  23.3  73.9  285   9  4  10.2   5.6
  6250  22.3  72.1  280  20 10   0.4   0.2 |  24.2  75.6  285   8  4  11.5   6.3
  6000  22.2  72.0  275  17  9   1.0   0.6 |  25.0  77.0  285   8  4  10.6   5.8
  5750  22.0  71.6  270  13  7  -2.8  -1.5 |  25.8  78.4  285   8  4  11.9   6.5
  5500  21.6  70.9  255   9  5  -0.6  -0.3 |  26.9  80.4  285   8  4  19.8  10.8

           06/02/2015 at 1500 MDT          |       06/02/2015 at 1800 MDT
                                           |
K index... +19.9  LI... +274.0             | K index... +19.1  LI... +272.9
CAPE... +21.9  CIN... -89.5                | CAPE... +163.2  CIN... -41.5
                                           |
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 -62.7 -80.9  270  16  8   2.1   1.1 | -63.1 -81.6  275  15  8   1.4   0.7
 45000 -59.4 -74.9  270  26 14   2.6   1.4 | -60.5 -76.9  270  23 12   3.1   1.7
 40000 -55.1 -67.2  280  38 20   5.0   2.7 | -55.5 -67.9  275  41 21   5.1   2.8
 38000 -52.0 -61.6  270  39 20   5.3   2.9 | -52.3 -62.1  265  41 21   5.4   2.9
 36000 -48.8 -55.8  265  41 21   5.3   2.9 | -49.1 -56.4  260  42 21   5.4   3.0
 34000 -44.7 -48.5  255  39 20   7.7   4.3 | -44.6 -48.3  260  40 21   8.5   4.6
 32000 -40.0 -40.0  250  35 18   7.7   4.2 | -39.6 -39.3  265  37 19   8.5   4.7
 30000 -35.5 -31.9  250  31 16   7.5   4.1 | -35.1 -31.2  265  36 18   6.8   3.8
 29000 -32.6 -26.7  255  29 15   7.5   4.1 | -32.6 -26.7  265  35 18   6.8   3.8
 28000 -30.4 -22.7  255  27 14   7.5   4.1 | -30.5 -22.9  270  34 17   7.0   3.8
 27000 -28.2 -18.8  255  26 13   7.5   4.1 | -28.3 -18.9  265  33 17   7.4   4.1
 26000 -25.9 -14.6  250  25 13   7.5   4.1 | -26.1 -15.0  265  31 16   7.4   4.1
 25000 -23.7 -10.7  250  24 12   7.3   4.0 | -23.9 -11.0  265  30 15   7.3   4.0
 24000 -21.1  -6.0  250  23 12   9.2   5.1 | -21.6  -6.9  260  29 15   8.0   4.4
 23000 -18.3  -0.9  250  23 12   9.3   5.1 | -19.2  -2.6  265  28 14   8.0   4.4
 22000 -15.6   3.9  255  23 12   9.6   5.2 | -16.9   1.6  265  27 14   8.0   4.4
 21000 -13.3   8.1  255  24 12   6.9   3.8 | -14.4   6.1  260  25 13   8.6   4.7
 20000 -11.3  11.7  260  26 13   7.0   3.8 | -11.9  10.6  260  23 12   8.7   4.8
 19500 -10.2  13.6  265  27 14   7.0   3.9 | -10.6  12.9  255  22 11   8.8   4.8
 19000  -9.2  15.4  265  27 14   7.2   3.9 |  -9.4  15.1  255  21 11   8.9   4.9
 18500  -8.2  17.2  260  26 13   7.3   4.0 |  -8.1  17.4  250  19 10   8.9   4.9
 18000  -7.2  19.0  260  25 13   7.5   4.1 |  -6.8  19.8  250  18  9   8.9   4.9
 17500  -6.0  21.2  255  23 12   8.7   4.8 |  -5.4  22.3  245  17  9   9.0   5.9
 17000  -4.8  23.4  255  22 11   8.7   4.8 |  -4.1  24.6  240  16  8   9.0   4.9
 16500  -3.5  25.7  250  20 10   8.6   4.7 |  -2.8  27.0  235  15  8   9.0   4.9
 16000  -2.3  27.9  250  19 10   8.6   4.7 |  -1.4  29.5  235  15  7   9.0   4.9
 15500  -0.4  31.3  245  17  9   8.6   4.7 |  -0.1  31.8  230  14  7   8.9   4.9
 15000   0.9  33.6  245  16  8   8.7   4.8 |   1.9  35.4  225  14  7   8.7   4.8
 14500   2.2  36.0  240  15  8   9.0   4.9 |   3.2  37.8  220  14  7   8.9   4.9
 14000   3.6  38.5  235  14  7   9.3   5.1 |   4.5  40.1  215  13  7   9.1   5.0
 13500   5.0  41.0  230  13  7   9.1   5.0 |   5.9  42.6  210  13  7   9.1   5.0
 13000   6.3  43.3  230  12  6   8.5   4.7 |   7.2  45.0  205  13  7   9.0   5.0
 12500   7.6  45.7  225  11  6   8.5   4.7 |   8.6  47.5  200  13  6   9.0   5.0
 12000   8.9  48.0  215  10  5   8.8   4.8 |   9.9  49.8  195  12  6   9.1   5.0
 11500  10.2  50.4  205   8  4   8.9   4.9 |  11.3  52.3  190  10  5   9.2   5.1
 11000  11.4  52.5  195   7  3   7.5   4.1 |  12.5  54.5  185   9  4   7.6   4.2
 10500  12.4  54.3  180   5  2  10.4   5.7 |  13.6  56.5  175   7  4  10.7   5.9
 10250  13.4  56.1  175   4  2  11.9   6.5 |  14.5  58.1  165   6  3  11.5   6.3
 10000  14.1  57.4  175   4  2   9.2   5.0 |  15.1  59.2  165   5  3   8.2   4.5
  9750  14.8  58.6  175   3  2   9.9   5.4 |  15.8  60.4  160   4  2   9.1   5.0
  9500  15.5  59.9  170   3  2   9.6   5.3 |  16.4  61.5  150   3  2   8.8   4.8
  9250  16.2  61.2  170   3  2   9.0   4.9 |  17.1  62.8  140   3  1   8.6   4.7
  9000  16.9  62.4  170   3  2   9.6   5.3 |  17.7  63.9  130   2  1   9.3   5.1
  8750  17.7  63.9  170   3  1  10.4   5.7 |  18.4  65.1  120   2  1  10.0   5.5
  8500  18.4  65.1  170   3  1  10.2   5.6 |  19.2  66.6  100   1  1   9.7   5.3
  8250  19.2  66.6  170   3  1  10.8   5.9 |  19.9  67.8  080   1  1  10.8   5.9
  8000  20.0  68.0  165   2  1  10.3   5.7 |  20.7  69.3  055   1  1  10.2   5.6
  7750  20.7  69.3  170   2  1   9.5   5.2 |  21.4  70.5  040   1  1   8.7   4.8
  7500  21.5  70.7  170   2  1   9.8   5.4 |  22.1  71.8  025   1  1   9.4   5.1
  7250  22.2  72.0  170   2  1  10.0   5.5 |  22.8  73.0  015   2  1  10.6   5.8
  7000  23.0  73.4  170   2  1  10.1   5.5 |  23.6  74.5  010   2  1  10.7   5.9
  6750  23.7  74.7  170   2  1   9.7   5.3 |  24.4  75.9  005   2  1   8.9   4.9
  6500  24.4  75.9  170   2  1  10.3   5.6 |  25.0  77.0  005   2  1   9.4   5.2
  6250  25.2  77.4  170   2  1  11.1   6.1 |  25.8  78.4  360   2  1  10.9   6.0
  6000  26.0  78.8  170   2  1  10.8   5.9 |  26.6  79.9  355   2  1  11.0   6.1
  5750  26.9  80.4  170   1  1  11.1   6.1 |  27.4  81.3  350   3  1   9.9   5.4
  5500  27.9  82.2  175   1  1  17.8   9.8 |  28.1  82.6  350   3  1  11.1   6.1
________________________________________________________________________________

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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