Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 011240
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0640 MDT Wednesday, April 1, 2015

This forecast is for Wednesday, April 1, 2015:

If the trigger temperature of 68.7 F/20.4 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 922 ft/min (4.7 m/s)
   Maximum height of thermals.................. 15246 ft MSL (9961 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1100 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................. 6257 ft MSL (972 ft AGL)
Thermal soaring outlook for Thursday 04/02..... Poor

Wave Soaring Index............................. Excellent
Wave Soaring Index trend (to 1800 MDT)......... Increasing
Height of stable layer (12-18K ft MSL)......... 14898 ft MSL (9613 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 15391 ft MSL (10106 ft AGL)
Wave soaring outlook for Thursday 04/02........ Fair

Remarks...

Sunrise/Sunset.................... 06:43:55 / 19:22:26 MDT
Total possible sunshine........... 12 hr 38 min 31 sec (758 min 31 sec)
Altitude of sun at 13:03:20 MDT... 54.88 degrees

Upper air data from rawinsonde observation taken on 04/01/2015 at 0600 MDT

Freezing level.................. 12210 ft MSL (6925 ft AGL)
Convective condensation level... 19248 ft MSL (13963 ft AGL)
Lifted condensation level....... 17880 ft MSL (12594 ft AGL)
Lifted index.................... +0.3
K index......................... +8.5

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  -59.2 -74.6   250   45   23   3.0   1.6   99.8 211.7    44.2      M    M
 45000  -56.9 -70.4   245   51   26   3.2   1.7   79.1 174.3    34.6      M    M
 40000  -59.3 -74.7   240   43   22 -16.5  -9.0   52.3 126.2    19.4      M    M
 38000  -63.1 -81.6   250   41   21   9.8   5.4   37.8 100.0    10.1      M    M
 36000  -59.0 -74.2   260   43   22   6.1   3.4   35.2  95.4     8.6      M    M
 34000  -54.6 -66.3   250   47   24   8.5   4.7   33.2  91.7     7.4      M    M
 32000  -48.9 -56.0   240   43   22   8.6   4.7   31.9  89.4     6.7      M    M
 30000  -43.8 -46.8   235   42   21   7.9   4.4   31.0  87.7     6.2      M    M
 29000  -41.4 -42.5   230   36   18   9.4   5.1   30.3  86.5     5.7      M    M
 28000  -38.5 -37.3   230   33   17   9.8   5.4   30.3  86.5     5.8      M    M
 27000  -35.6 -32.1   235   31   16   8.1   4.5   30.2  86.4     5.8      M    M
 26000  -33.2 -27.8   235   28   14   8.1   4.5   29.6  85.3     5.4      M    M
 25000  -30.9 -23.6   220   27   14   5.8   3.2   28.8  83.9     4.8      M    M
 24000  -28.9 -20.0   225   24   12   9.2   5.1   27.6  81.8     3.9      M    M
 23000  -26.1 -15.0   225   23   12   9.3   5.1   27.4  81.4     3.8      M    M
 22000  -23.3  -9.9   230   21   11   9.4   5.1   27.3  81.1     3.7      M    M
 21000  -20.4  -4.7   230   20   10   9.4   5.1   27.1  80.8     3.6      M    M
 20000  -17.6   0.3   235   19   10   9.4   5.1   27.1  80.7     3.6      M    M
 19500  -16.2   2.8   240   19   10   9.1   5.0   27.0  80.5     3.6      M    M
 19000  -14.9   5.2   250   19   10   8.7   4.8   26.8  80.2     3.4      M    M
 18500  -13.6   7.5   255   20   10   8.3   4.5   26.6  79.9     3.3      M    M
 18000  -12.4   9.7   260   20   10   8.0   4.4   26.2  79.2     3.0      M    M
 17500  -11.2  11.8   260   20   10   7.9   4.4   25.9  78.6     2.7      M    M
 17000  -10.0  14.0   265   20   10   8.0   4.4   25.6  78.1     2.5      M    M
 16500   -8.8  16.2   265   20   10   8.4   4.6   25.3  77.6     2.2      M    M
 16000   -7.7  18.1   270   22   11   3.7   2.0   24.3  75.7     1.2      M    M
 15500   -7.2  19.0   275   32   17   4.6   2.5   23.2  73.8     0.3      M    M
 15000   -7.0  19.4   275   39   20  -0.9  -0.5   21.9  71.4    -1.1    912  4.6
 14500   -6.3  20.7   275   36   19   9.7   5.3   21.2  70.1    -1.8    876  4.5
 14000   -4.9  23.2   275   34   17   9.5   5.2   21.1  70.0    -1.8    819  4.2
 13500   -3.5  25.7   275   31   16   9.5   5.2   21.1  69.9    -1.9    761  3.9
 13000   -2.1  28.2   275   28   14   9.5   5.2   21.0  69.8    -2.0    704  3.6
 12500   -0.6  30.9   275   25   13   9.5   5.2   21.0  69.8    -2.0    647  3.3
 12000    0.8  33.4   275   23   12   9.5   5.2   21.0  69.8    -2.0    589  3.0
 11500    2.2  36.0   275   23   12   9.5   5.2   20.9  69.7    -2.1    532  2.7
 11000    3.6  38.5   275   22   12   9.5   5.2   20.9  69.6    -2.2    475  2.4
 10500    5.1  41.2   280   22   11   9.7   5.3   20.8  69.5    -2.2    417  2.1
 10250    5.8  42.4   280   22   11   9.7   5.3   20.8  69.5    -2.2    388  2.0
 10000    6.5  43.7   280   22   11   9.6   5.3   20.8  69.5    -2.2    358  1.8
  9750    7.2  45.0   275   20   11   9.6   5.2   20.8  69.5    -2.3    330  1.7
  9500    7.9  46.2   270   19   10   9.6   5.3   20.8  69.5    -2.3    301  1.5
  9250    8.6  47.5   265   17    9   9.6   5.3   20.8  69.5    -2.3    272  1.4
  9000    9.4  48.9   260   16    8   9.6   5.3   20.8  69.5    -2.3    243  1.2
  8750   10.1  50.2   260   15    8   9.6   5.3   20.8  69.4    -2.3    214  1.1
  8500   10.8  51.4   260   15    8   9.6   5.3   20.8  69.4    -2.3    185  0.9
  8250   11.5  52.7   260   14    7   9.6   5.3   20.8  69.4    -2.4    157  0.8
  8000   12.2  54.0   260   14    7   9.6   5.3   20.8  69.4    -2.4    128  0.6
  7750   12.9  55.2   260   14    7   9.6   5.3   20.7  69.3    -2.4     99  0.5
  7500   13.6  56.5   255   15    8   9.6   5.2   20.7  69.3    -2.4     70  0.4
  7250   14.4  57.9   255   15    8   9.6   5.3   20.7  69.3    -2.5     41  0.2
  7000   15.1  59.2   255   16    8   9.4   5.2   20.7  69.3    -2.5     13  0.1
  6750   15.8  60.4   245   16    8  10.1   5.5   20.7  69.2    -2.5      M    M
  6500   16.5  61.7   235   17    9   7.8   4.3   20.6  69.2    -2.6      M    M
  6250   16.8  62.2   230   18    9   1.5   0.8   20.3  68.5    -3.0      M    M
  6000   16.9  62.4   220   19   10   3.4   1.9   19.6  67.3    -3.6      M    M
  5750   17.0  62.6   210   15    8  -8.4  -4.6   18.9  66.1    -4.3      M    M
  5500   15.1  59.2   195   11    6 -41.5 -22.8   16.3  61.4    -7.0      M    M

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

           04/01/2015 at 0900 MDT          |       04/01/2015 at 1200 MDT
                                           |
K index... +8.7  LI... +275.7              | K index... +10.9  LI... +274.5
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 -57.9 -72.2  255  22 11   2.4   1.3 | -57.7 -71.9  250  26 13   3.5   1.9
 45000 -54.2 -65.6  255  41 21  -0.0  -0.0 | -52.2 -62.0  255  37 19   0.7   0.4
 40000 -58.7 -73.7  250  46 24  -3.0  -1.7 | -58.1 -72.6  245  53 27  -4.0  -2.2
 38000 -58.9 -74.0  245  47 24   3.0   1.7 | -58.8 -73.8  245  56 29   2.9   1.6
 36000 -57.1 -70.8  250  45 23   3.0   1.6 | -57.1 -70.8  245  53 27   2.8   1.5
 34000 -55.0 -67.0  250  44 22   7.9   4.3 | -55.2 -67.4  245  50 26   7.1   3.9
 32000 -49.8 -57.6  245  42 22   7.7   4.2 | -50.1 -58.2  240  46 24   7.5   4.1
 30000 -45.1 -49.2  240  40 21   8.5   4.7 | -45.5 -49.9  235  43 22   8.0   4.4
 29000 -42.5 -44.5  240  39 20   8.6   4.7 | -43.1 -45.6  235  42 22   8.1   4.4
 28000 -39.9 -39.8  235  38 20   8.6   4.7 | -40.7 -41.3  230  42 22   8.1   4.4
 27000 -37.4 -35.3  230  37 19   8.5   4.6 | -38.3 -36.9  230  41 21   8.4   4.6
 26000 -34.9 -30.8  230  36 19   8.4   4.6 | -35.7 -32.3  230  38 19   8.7   4.8
 25000 -32.4 -26.3  230  35 18   8.4   4.6 | -33.1 -27.6  230  34 17   8.7   4.8
 24000 -29.9 -21.8  230  35 18   8.3   4.6 | -30.5 -22.9  230  30 15   8.7   4.8
 23000 -27.4 -17.3  230  32 16   8.2   4.5 | -27.9 -18.2  230  28 14   8.3   4.6
 22000 -24.9 -12.8  230  29 15   8.2   4.5 | -25.5 -13.9  235  26 13   8.3   4.6
 21000 -22.5  -8.5  230  27 14   8.2   4.5 | -23.0  -9.4  240  24 12   8.1   4.4
 20000 -20.0  -4.0  235  24 12   8.2   4.5 | -20.6  -5.1  250  25 13   7.9   4.3
 19500 -18.8  -1.8  240  23 12   8.2   4.5 | -19.4  -2.9  260  26 14   7.9   4.3
 19000 -17.6   0.3  245  22 11   8.2   4.5 | -18.2  -0.8  260  27 14   7.9   4.3
 18500 -16.4   2.5  250  21 11   8.1   4.4 | -17.0   1.4  265  29 15   7.9   4.3
 18000 -15.2   4.6  255  21 11   8.0   4.4 | -15.9   3.4  270  29 15   7.9   4.3
 17500 -14.0   6.8  260  22 11   8.1   4.4 | -14.7   5.5  275  29 15   8.0   4.4
 17000 -12.3   9.9  265  23 12   7.4   4.0 | -13.6   7.5  275  29 15   6.9   3.8
 16500 -11.2  11.8  270  24 12   7.4   4.0 | -12.0  10.4  280  27 14   7.0   3.8
 16000 -10.2  13.6  275  25 13   7.3   4.0 | -10.9  12.4  280  27 14   7.6   4.2
 15500  -9.1  15.6  275  26 13   7.3   4.0 |  -9.8  14.4  285  27 14   7.5   4.1
 15000  -8.0  17.6  280  27 14   7.4   4.1 |  -8.7  16.3  285  26 13   8.4   4.6
 14500  -6.9  19.6  280  27 14   7.4   4.1 |  -7.4  18.7  285  24 13   8.5   4.7
 14000  -5.8  21.6  280  27 14   7.9   4.3 |  -6.2  20.8  285  23 12   8.5   4.7
 13500  -4.6  23.7  285  26 13   8.1   4.5 |  -4.9  23.2  285  22 11   8.5   4.6
 13000  -3.4  25.9  285  25 13   8.8   4.8 |  -3.7  25.3  285  21 11   8.5   4.7
 12500  -2.0  28.4  290  24 13   9.5   5.2 |  -2.4  27.7  285  20 10   8.6   4.7
 12000  -0.6  30.9  290  24 12   9.3   5.1 |  -1.1  30.0  290  19 10   8.5   4.7
 11500   0.8  33.4  295  23 12   9.0   4.9 |   0.1  32.2  290  18  9   8.4   4.6
 11000   2.1  35.8  295  23 12   8.9   4.9 |   1.4  34.5  290  16  8   8.2   4.5
 10500   3.4  38.1  295  23 12   8.4   4.6 |   2.6  36.7  295  15  8   7.5   4.1
 10250   4.0  39.2  295  22 11  10.3   5.6 |   3.1  37.6  295  15  8   9.1   5.0
 10000   4.9  40.8  300  22 11  10.8   5.9 |   3.9  39.0  295  14  7   9.8   5.4
  9750   5.6  42.1  300  22 11   8.9   4.9 |   4.5  40.1  295  14  7   8.2   4.5
  9500   6.3  43.3  300  22 11   8.9   4.9 |   5.1  41.2  295  13  7   8.6   4.7
  9250   6.9  44.4  300  22 11   9.0   4.9 |   5.8  42.4  300  12  6   7.3   4.0
  9000   7.6  45.7  300  21 11   8.1   4.4 |   6.3  43.3  300  12  6   7.6   4.2
  8750   8.1  46.6  300  21 11   7.3   4.0 |   6.9  44.4  295  11  6   9.1   5.0
  8500   8.7  47.7  295  21 11   7.5   4.1 |   7.6  45.7  295  10  5   8.5   4.7
  8250   9.3  48.7  295  20 11   7.7   4.2 |   8.2  46.8  295   9  5   9.4   5.1
  8000   9.8  49.6  290  20 10   7.7   4.2 |   8.9  48.0  295   8  4  10.7   5.9
  7750  10.4  50.7  290  19 10   6.6   3.6 |   9.7  49.5  290   8  4   9.8   5.4
  7500  10.8  51.4  285  18  9   5.9   3.2 |  10.4  50.7  290   8  4   8.7   4.7
  7250  11.3  52.3  280  17  9   6.9   3.8 |  11.1  52.0  290   8  4   9.6   5.2
  7000  11.9  53.4  275  16  8   8.5   4.7 |  11.8  53.2  290   8  4  10.4   5.7
  6750  12.5  54.5  270  14  7   7.8   4.3 |  12.6  54.7  290   8  4   9.9   5.4
  6500  13.0  55.4  265  13  7   7.9   4.3 |  13.3  55.9  290   8  4   9.3   5.1
  6250  13.5  56.3  255  12  6   1.5   0.8 |  14.0  57.2  290   7  4  10.3   5.6
  6000  13.2  55.8  250  12  6  -2.5  -1.4 |  14.8  58.6  290   7  4  11.3   6.2
  5750  12.9  55.2  240  11  6  -8.1  -4.4 |  15.7  60.3  290   7  4  10.0   5.5
  5500  11.7  53.1  230  10  5 -21.3 -11.7 |  16.5  61.7  290   7  4  14.3   7.9

           04/01/2015 at 1500 MDT          |       04/01/2015 at 1800 MDT
                                           |
K index... +21.1  LI... +272.1             | K index... +20.8  LI... +271.7
CAPE... +44.8  CIN... -23.4                | CAPE... +224.9  CIN... -20.7
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -57.3 -71.1  250  35 18   3.2   1.7 | -56.6 -69.9  255  32 17   2.9   1.6
 45000 -52.3 -62.1  255  50 26   0.4   0.2 | -52.0 -61.6  255  51 26   1.1   0.6
 40000 -58.6 -73.5  245  60 31  -4.3  -2.3 | -56.4 -69.5  255  55 28  -3.0  -1.7
 38000 -59.5 -75.1  245  61 31   3.0   1.7 | -57.4 -71.3  250  55 28   0.5   0.3
 36000 -57.7 -71.9  240  58 30   3.0   1.6 | -57.1 -70.8  245  53 27   0.5   0.3
 34000 -55.6 -68.1  240  54 28   7.7   4.2 | -56.6 -69.9  235  52 27   6.4   3.5
 32000 -50.8 -59.4  240  50 26   8.1   4.5 | -51.6 -60.9  240  49 25   8.2   4.5
 30000 -45.2 -49.4  245  47 24   8.5   4.6 | -46.1 -51.0  240  47 24   7.9   4.3
 29000 -42.7 -44.9  245  46 24   8.5   4.7 | -43.8 -46.8  245  44 23   7.9   4.3
 28000 -40.1 -40.2  245  45 23   8.5   4.7 | -41.4 -42.5  250  42 22   7.9   4.3
 27000 -37.6 -35.7  245  44 23   8.3   4.5 | -39.1 -38.4  250  40 21   8.1   4.5
 26000 -35.2 -31.4  245  42 22   8.0   4.4 | -36.5 -33.7  255  38 19   8.5   4.6
 25000 -32.8 -27.0  245  39 20   8.0   4.4 | -34.0 -29.2  255  35 18   8.5   4.6
 24000 -30.4 -22.7  250  37 19   7.9   4.4 | -31.5 -24.7  260  33 17   8.4   4.6
 23000 -28.1 -18.6  250  35 18   7.5   4.1 | -29.1 -20.4  255  31 16   7.9   4.3
 22000 -25.9 -14.6  255  34 18   7.5   4.1 | -26.8 -16.2  250  29 15   7.9   4.3
 21000 -23.7 -10.7  255  33 17   7.6   4.2 | -24.5 -12.1  245  27 14   8.3   4.5
 20000 -21.4  -6.5  260  32 17   7.7   4.2 | -21.9  -7.4  245  26 14   8.6   4.7
 19500 -20.3  -4.5  260  32 16   7.7   4.2 | -20.7  -5.3  245  26 13   8.6   4.7
 19000 -19.2  -2.6  260  32 16   7.7   4.2 | -19.4  -2.9  245  25 13   8.6   4.7
 18500 -18.0  -0.4  260  31 16   8.0   4.4 | -18.1  -0.6  240  25 13   8.5   4.7
 18000 -16.8   1.8  260  30 16   8.4   4.6 | -16.9   1.6  240  24 13   8.3   4.5
 17500 -15.6   3.9  260  29 15   8.4   4.6 | -15.7   3.7  240  24 12   8.2   4.5
 17000 -14.3   6.3  255  28 14   8.3   4.6 | -14.4   6.1  240  23 12   8.5   4.6
 16500 -13.1   8.4  255  26 13   8.4   4.6 | -13.2   8.2  235  22 12   8.5   4.6
 16000 -11.2  11.8  250  23 12   8.5   4.7 | -11.9  10.6  235  22 11   8.7   4.8
 15500 -10.0  14.0  250  22 11   8.5   4.7 |  -9.9  14.2  230  20 11   9.0   4.9
 15000  -8.7  16.3  250  20 10   8.7   4.8 |  -8.6  16.5  230  20 10   9.1   5.0
 14500  -7.4  18.7  245  19 10   8.8   4.8 |  -7.2  19.0  230  19 10   9.2   5.0
 14000  -6.1  21.0  240  18  9   9.1   5.0 |  -5.9  21.4  230  18  9   9.3   5.1
 13500  -4.7  23.5  240  17  9   9.3   5.1 |  -4.5  23.9  230  17  9   9.4   5.2
 13000  -3.3  26.1  235  16  8   9.3   5.1 |  -3.1  26.4  230  16  8   9.5   5.2
 12500  -2.0  28.4  230  16  8   9.3   5.1 |  -1.6  29.1  230  15  8   9.6   5.3
 12000  -0.6  30.9  225  15  8   9.2   5.0 |  -0.2  31.6  230  15  8   9.6   5.3
 11500   0.8  33.4  225  15  8   9.0   4.9 |   1.2  34.2  230  14  7   9.6   5.3
 11000   2.1  35.8  220  14  7   8.6   4.7 |   2.7  36.9  230  14  7   9.3   5.1
 10500   3.3  37.9  220  12  6   7.4   4.0 |   4.0  39.2  230  13  7   8.1   4.5
 10250   3.9  39.0  215  11  5   8.8   4.9 |   4.6  40.3  230  12  6   9.6   5.3
 10000   4.6  40.3  215   9  5   9.9   5.4 |   5.4  41.7  230  12  6  10.6   5.8
  9750   5.3  41.5  215   8  4   8.9   4.9 |   6.1  43.0  235  11  6   9.6   5.3
  9500   5.9  42.6  215   7  4   9.1   5.0 |   6.8  44.2  235  10  5   9.7   5.3
  9250   6.6  43.9  220   6  3   8.4   4.6 |   7.5  45.5  240   8  4   9.2   5.0
  9000   7.2  45.0  220   5  2   8.6   4.7 |   8.2  46.8  245   8  4   8.2   4.5
  8750   7.9  46.2  220   4  2   9.8   5.4 |   8.8  47.8  250   7  3   8.5   4.7
  8500   8.6  47.5  220   4  2   9.7   5.3 |   9.4  48.9  260   6  3   8.8   4.8
  8250   9.4  48.9  225   4  2  10.2   5.6 |  10.1  50.2  270   5  3   8.9   4.9
  8000  10.2  50.4  225   4  2  11.3   6.2 |  10.8  51.4  285   5  2  10.6   5.8
  7750  11.0  51.8  225   4  2  10.3   5.7 |  11.6  52.9  295   5  2  10.0   5.5
  7500  11.7  53.1  230   4  2   9.1   5.0 |  12.2  54.0  300   5  3   8.4   4.6
  7250  12.4  54.3  230   4  2   9.8   5.4 |  12.8  55.0  305   5  3   9.3   5.1
  7000  13.2  55.8  230   4  2  10.3   5.7 |  13.6  56.5  310   5  3  10.5   5.8
  6750  13.9  57.0  235   4  2  10.1   5.6 |  14.4  57.9  310   5  3   9.9   5.4
  6500  14.7  58.5  235   4  2   9.5   5.2 |  15.0  59.0  310   6  3   8.8   4.8
  6250  15.4  59.7  235   4  2  10.5   5.8 |  15.7  60.3  310   6  3   9.6   5.3
  6000  16.2  61.2  240   4  2  11.9   6.5 |  16.5  61.7  315   6  3  10.4   5.7
  5750  17.1  62.8  240   3  2  10.1   5.6 |  17.2  63.0  315   6  3  10.2   5.6
  5500  17.9  64.2  245   3  2  13.4   7.4 |  18.0  64.4  315   6  3  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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