Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 030125
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1925 MDT Saturday, May 2, 2015

This forecast is for Sunday, May 3, 2015:

If the trigger temperature of 70.5 F/21.4 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 595 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14091 ft MSL (8784 ft AGL)

Forecast maximum temperature................... 74.0 F/23.8 C
Time of trigger temperature.................... 1115 MDT
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................. 6507 ft MSL (1200 ft AGL)
Thermal soaring outlook for Monday 05/04....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 18606 ft MSL (13299 ft AGL)
Wave soaring outlook for Monday 05/04.......... Poor

Remarks... Weak winds aloft Sunday. Airmass becoming unstable in the afternoon
           with scattered thunderstorms developing.

Sunrise/Sunset.................... 05:57:55 / 19:54:37 MDT
Total possible sunshine........... 13 hr 56 min 42 sec (836 min 42 sec)
Altitude of sun at 12:56:26 MDT... 65.97 degrees

Upper air data from numerical model forecast valid on 05/03/2015 at 0600 MDT

Freezing level.................. 12932 ft MSL (7625 ft AGL)
Convective condensation level... 16261 ft MSL (10954 ft AGL)
Lifted condensation level....... 15927 ft MSL (10621 ft AGL)
Lifted index.................... -0.3
K index......................... +11.8

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  -61.0 -77.8   275   32   16  -0.9  -0.5      M     M       M      M    M
 45000  -62.3 -80.1   275   33   17  -0.1  -0.1      M     M       M      M    M
 40000  -62.3 -80.1   260   30   15  -0.1  -0.0      M     M       M      M    M
 38000  -60.1 -76.2   260   33   17   5.7   3.1      M     M       M      M    M
 36000  -56.7 -70.1   255   39   20   5.7   3.1      M     M       M      M    M
 34000  -52.8 -63.0   255   43   22   8.5   4.7      M     M       M      M    M
 32000  -47.0 -52.6   260   42   22   8.6   4.7      M     M       M      M    M
 30000  -41.8 -43.2   260   38   20   8.9   4.9   33.0  91.3     7.3      M    M
 29000  -39.1 -38.4   265   35   18   8.9   4.9   32.6  90.7     7.1      M    M
 28000  -36.4 -33.5   270   31   16   8.9   4.9   32.4  90.3     7.0      M    M
 27000  -33.8 -28.8   270   28   14   8.3   4.5   32.0  89.7     6.8      M    M
 26000  -31.3 -24.3   270   25   13   8.3   4.6   31.4  88.5     6.4      M    M
 25000  -28.8 -19.8   270   22   12   8.3   4.6   30.9  87.6     6.0      M    M
 24000  -26.3 -15.3   275   20   10   8.4   4.6   30.5  86.8     5.7      M    M
 23000  -23.8 -10.8   275   18    9   8.4   4.6   29.9  85.8     5.3      M    M
 22000  -21.3  -6.3   275   16    8   8.4   4.6   29.4  85.0     5.0      M    M
 21000  -18.9  -2.0   280   15    8   7.0   3.8   28.8  83.9     4.5      M    M
 20000  -16.8   1.8   290   16    8   7.1   3.9   27.8  82.1     3.7      M    M
 19500  -15.7   3.7   295   16    8   7.1   3.9   27.4  81.3     3.4      M    M
 19000  -14.7   5.5   300   17    9   7.1   3.9   27.0  80.5     3.0      M    M
 18500  -13.6   7.5   305   18    9   7.0   3.9   26.5  79.7     2.6      M    M
 18000  -12.6   9.3   305   17    9   7.1   3.9   26.0  78.9     2.2      M    M
 17500  -11.6  11.1   310   17    9   7.3   4.0   25.6  78.1     1.8      M    M
 17000   -9.9  14.2   320   16    8   7.6   4.2   25.0  77.0     1.3      M    M
 16500   -8.7  16.3   325   16    8   8.1   4.5   24.7  76.4     1.0      M    M
 16000   -7.5  18.5   325   16    8   8.6   4.7   24.5  76.1     0.8      M    M
 15500   -6.2  20.8   330   16    8   8.6   4.7   24.3  75.7     0.6      M    M
 15000   -4.9  23.2   330   16    8   8.3   4.6   24.1  75.3     0.4      M    M
 14500   -3.7  25.3   335   15    8   8.4   4.6   23.8  74.9     0.2      M    M
 14000   -2.5  27.5   335   15    8   8.3   4.6   23.6  74.5    -0.1    778  4.0
 13500   -1.3  29.7   335   14    7   8.3   4.6   23.4  74.0    -0.3    726  3.7
 13000   -0.0  32.0   340   13    7   8.6   4.7   23.2  73.7    -0.6    674  3.4
 12500    1.3  34.3   340   13    6   8.7   4.8   23.0  73.3    -0.7    621  3.2
 12000    2.5  36.5   340   12    6   8.5   4.7   22.8  73.0    -0.9    568  2.9
 11500    3.8  38.8   340   12    6   8.5   4.7   22.6  72.7    -1.1    516  2.6
 11000    5.0  41.0   340   11    6   8.2   4.5   22.4  72.3    -1.3    463  2.4
 10500    6.3  43.3   340   11    6   7.5   4.1   22.1  71.8    -1.6    412  2.1
 10250    6.9  44.4   335   11    6  10.4   5.7   22.0  71.6    -1.7    387  2.0
 10000    7.7  45.9   335   11    6  10.8   5.9   22.2  71.9    -1.6    353  1.8
  9750    8.4  47.1   330   11    6   8.2   4.5   22.1  71.7    -1.7    326  1.7
  9500    9.0  48.2   330   11    5   9.0   4.9   22.0  71.6    -1.8    300  1.5
  9250    9.7  49.5   330   10    5   8.3   4.6   21.9  71.5    -1.9    273  1.4
  9000   10.3  50.5   325   10    5   8.8   4.8   21.8  71.3    -2.0    247  1.3
  8750   11.0  51.8   325   10    5   9.7   5.3   21.8  71.2    -2.0    219  1.1
  8500   11.7  53.1   320   10    5   9.4   5.2   21.8  71.2    -2.1    191  1.0
  8250   12.4  54.3   320   10    5   9.6   5.3   21.8  71.2    -2.1    162  0.8
  8000   13.1  55.6   315   10    5   9.2   5.1   21.7  71.1    -2.1    134  0.7
  7750   13.7  56.7   315   11    6   8.4   4.6   21.7  71.0    -2.2    107  0.5
  7500   14.3  57.7   310   11    6   8.2   4.5   21.5  70.8    -2.4     82  0.4
  7250   14.9  58.8   310   11    6   8.7   4.8   21.4  70.6    -2.5     57  0.3
  7000   15.5  59.9   310   12    6   8.5   4.7   21.4  70.5    -2.6     30  0.2
  6750   16.2  61.2   310   12    6   9.3   5.1   21.3  70.3    -2.7      4  0.0
  6500   16.8  62.2   310   13    6   3.8   2.1   21.1  70.1    -2.9      M    M
  6250   16.5  61.7   305   12    6  -8.8  -4.8   20.2  68.4    -3.8      M    M
  6000   15.6  60.1   300   11    6 -12.1  -6.7   18.6  65.4    -5.5      M    M
  5750   14.6  58.3   290   10    5 -16.2  -8.9   16.9  62.4    -7.3     22  0.1
  5500   12.4  54.3   265   11    6 -46.1 -25.3   14.0  57.2   -10.2     81  0.4

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

           05/03/2015 at 0900 MDT          |       05/03/2015 at 1200 MDT
                                           |
K index... +10.9  LI... +273.4             | K index... +14.4  LI... +271.4
CAPE... 0.0  CIN... -0.7                   | CAPE... +243.8  CIN... -25.9
                                           |
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 -60.7 -77.3  280  31 16  -0.6  -0.3 | -60.5 -76.9  275  34 17  -0.2  -0.1
 45000 -61.6 -78.9  270  35 18  -0.9  -0.5 | -60.8 -77.4  270  36 19  -1.2  -0.7
 40000 -63.1 -81.6  255  30 15  -1.0  -0.6 | -62.9 -81.2  255  32 16  -1.5  -0.8
 38000 -60.9 -77.6  255  30 15   6.5   3.5 | -60.9 -77.6  250  30 16   6.6   3.6
 36000 -57.0 -70.6  250  30 16   6.5   3.5 | -56.4 -69.5  245  29 15   6.6   3.6
 34000 -52.2 -62.0  250  32 16   8.0   4.4 | -52.2 -62.0  245  28 15   7.8   4.3
 32000 -47.4 -53.3  250  34 17   8.0   4.4 | -47.5 -53.5  245  29 15   7.8   4.3
 30000 -42.3 -44.1  250  33 17   9.2   5.0 | -42.3 -44.1  245  28 14   9.5   5.2
 29000 -39.6 -39.3  255  31 16   9.2   5.0 | -39.5 -39.1  250  26 13   9.5   5.2
 28000 -36.8 -34.2  265  30 15   9.2   5.0 | -36.6 -33.9  255  24 12   9.5   5.2
 27000 -34.1 -29.4  265  28 14   8.4   4.6 | -33.9 -29.0  255  22 11   7.8   4.3
 26000 -31.6 -24.9  265  25 13   8.5   4.7 | -31.6 -24.9  255  21 11   7.9   4.3
 25000 -29.0 -20.2  260  22 11   8.5   4.7 | -29.2 -20.6  255  20 10   7.9   4.3
 24000 -26.5 -15.7  260  19 10   8.2   4.5 | -26.8 -16.2  255  18 10   7.8   4.3
 23000 -24.1 -11.4  260  17  9   8.2   4.5 | -24.5 -12.1  260  17  9   7.8   4.3
 22000 -21.6  -6.9  260  16  8   8.2   4.5 | -22.2  -8.0  260  16  8   7.8   4.3
 21000 -19.3  -2.7  265  14  7   6.3   3.4 | -19.9  -3.8  265  15  8   6.9   3.8
 20000 -17.4   0.7  280  14  7   6.4   3.5 | -17.8  -0.0  270  15  8   7.0   3.8
 19500 -16.5   2.3  285  14  7   6.4   3.5 | -16.8   1.8  275  15  8   7.0   3.8
 19000 -15.5   4.1  290  14  7   6.3   3.4 | -15.8   3.6  275  15  8   6.8   3.7
 18500 -14.5   5.9  295  13  7   7.8   4.3 | -14.0   6.8  280  15  7   8.4   4.6
 18000 -13.3   8.1  300  13  7   7.8   4.3 | -12.8   9.0  285  14  7   8.4   4.6
 17500 -11.5  11.3  305  12  6   8.7   4.8 | -11.5  11.3  290  14  7   9.0   5.0
 17000 -10.3  13.5  310  12  6   8.7   4.8 | -10.1  13.8  290  14  7   9.0   4.9
 16500  -9.0  15.8  310  12  6   8.7   4.8 |  -8.8  16.2  295  13  7   8.7   4.8
 16000  -7.7  18.1  315  12  6   8.7   4.8 |  -7.6  18.3  295  12  6   8.6   4.7
 15500  -6.4  20.5  315  12  6   8.5   4.7 |  -6.3  20.7  300  11  6   8.4   4.6
 15000  -5.2  22.6  315  11  6   7.8   4.3 |  -5.1  22.8  300  10  5   8.0   4.4
 14500  -4.0  24.8  320  11  6   7.8   4.3 |  -3.9  25.0  305   9  5   8.0   4.4
 14000  -2.9  26.8  320  10  5   8.4   4.6 |  -2.7  27.1  310   8  4   8.3   4.5
 13500  -1.6  29.1  330  10  5   8.4   4.6 |  -1.5  29.3  315   6  3   8.2   4.5
 13000  -0.4  31.3  335  10  5   8.7   4.8 |  -0.2  31.6  325   5  2   8.8   4.8
 12500   0.9  33.6  340   9  5   8.6   4.7 |   1.1  34.0  335   4  2   8.7   4.8
 12000   2.2  36.0  345   9  5   9.5   5.2 |   2.4  36.3  350   3  2   8.8   4.8
 11500   3.6  38.5  350   9  5   9.7   5.3 |   3.7  38.7  010   3  2   8.9   4.9
 11000   5.0  41.0  350   9  5   8.1   4.5 |   4.9  40.8  025   4  2   8.0   4.4
 10500   6.2  43.2  350   9  5   7.2   3.9 |   6.1  43.0  035   4  2   7.1   3.9
 10250   6.7  44.1  355   9  5  10.9   6.0 |   6.7  44.1  040   5  2  11.3   6.2
 10000   7.7  45.9  355   9  5  11.5   6.3 |   7.7  45.9  045   5  3  12.0   6.6
  9750   8.4  47.1  355   9  5   8.3   4.5 |   8.4  47.1  045   5  3   8.3   4.6
  9500   9.0  48.2  355   9  5   9.2   5.1 |   9.0  48.2  050   6  3   9.4   5.1
  9250   9.7  49.5  355   9  5   8.7   4.8 |   9.7  49.5  055   6  3   9.1   5.0
  9000  10.3  50.5  355   9  5   8.9   4.9 |  10.3  50.5  055   6  3   9.7   5.3
  8750  11.0  51.8  355   9  5   9.2   5.0 |  11.1  52.0  055   6  3  10.2   5.6
  8500  11.7  53.1  355   9  5   9.1   5.0 |  11.8  53.2  055   6  3  10.1   5.5
  8250  12.3  54.1  355   9  5   9.3   5.1 |  12.5  54.5  060   6  3  10.3   5.7
  8000  13.0  55.4  350   9  5   9.2   5.0 |  13.3  55.9  060   6  3  10.0   5.5
  7750  13.7  56.7  350   9  5   8.9   4.9 |  14.0  57.2  060   6  3   9.3   5.1
  7500  14.4  57.9  345   9  5   8.9   4.9 |  14.7  58.5  060   5  3   9.4   5.2
  7250  15.0  59.0  340  10  5   9.1   5.0 |  15.4  59.7  060   5  3  10.2   5.6
  7000  15.7  60.3  335  10  5   8.8   4.8 |  16.2  61.2  060   5  3  10.5   5.8
  6750  16.3  61.3  330  11  6   8.9   4.9 |  17.0  62.6  060   5  3  10.2   5.6
  6500  16.9  62.4  320  12  6   4.2   2.3 |  17.7  63.9  060   5  3  10.3   5.7
  6250  16.9  62.4  315  11  5  -2.3  -1.3 |  18.5  65.3  060   5  3  10.8   5.9
  6000  16.6  61.9  310   9  4  -2.3  -1.2 |  19.3  66.7  060   5  3  10.4   5.7
  5750  16.2  61.2  295   7  3  -8.3  -4.5 |  20.1  68.2  060   5  2  11.6   6.4
  5500  15.2  59.4  245   4  2 -12.3  -6.8 |  21.2  70.2  055   5  2  18.8  10.3

           05/03/2015 at 1500 MDT          |       05/03/2015 at 1800 MDT
                                           |
K index... +20.2  LI... +271.0             | K index... +27.0  LI... +271.5
CAPE... +274.1  CIN... -12.5               | CAPE... +247.7  CIN... -3.0
                                           |
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  275  34 17   0.2   0.1 | -61.2 -78.2  280  35 18   0.4   0.2
 45000 -61.0 -77.8  265  36 19  -0.6  -0.3 | -60.6 -77.1  270  35 18  -1.9  -1.0
 40000 -62.4 -80.3  265  33 17  -0.7  -0.4 | -64.6 -84.3  250  36 19  -2.3  -1.2
 38000 -60.0 -76.0  260  33 17   6.0   3.3 | -61.6 -78.9  250  35 18   7.9   4.4
 36000 -56.4 -69.5  255  33 17   6.0   3.3 | -56.8 -70.2  245  31 16   7.9   4.4
 34000 -52.1 -61.8  250  32 16   9.1   5.0 | -51.7 -61.1  245  28 15   9.5   5.2
 32000 -46.7 -52.1  250  28 14   9.0   5.0 | -46.1 -51.0  245  25 13   9.4   5.2
 30000 -41.4 -42.5  255  24 12   8.8   4.8 | -40.5 -40.9  240  21 11   8.9   4.9
 29000 -38.1 -36.6  250  21 11   8.8   4.8 | -37.2 -35.0  240  18  9   9.0   4.9
 28000 -35.5 -31.9  250  19 10   8.8   4.8 | -34.5 -30.1  240  15  8   8.9   4.9
 27000 -33.0 -27.4  250  17  9   8.1   4.4 | -32.0 -25.6  240  13  7   8.0   4.4
 26000 -30.6 -23.1  250  15  8   8.1   4.4 | -29.7 -21.5  245  11  6   8.0   4.4
 25000 -28.2 -18.8  250  14  7   8.1   4.4 | -27.3 -17.1  245   9  4   8.0   4.4
 24000 -25.8 -14.4  250  13  6   7.2   4.0 | -25.0 -13.0  250   7  4   7.5   4.1
 23000 -23.6 -10.5  260  12  6   7.3   4.0 | -22.7  -8.9  245   7  3   7.6   4.2
 22000 -21.5  -6.7  270  11  6   7.3   4.0 | -20.5  -4.9  245   6  3   7.6   4.2
 21000 -19.3  -2.7  275  10  5   6.9   3.8 | -18.4  -1.1  235   6  3   6.7   3.7
 20000 -17.3   0.9  275  10  5   7.0   3.8 | -16.4   2.5  220   6  3   6.7   3.7
 19500 -16.2   2.8  275  10  5   7.0   3.8 | -15.4   4.3  210   7  3   6.7   3.7
 19000 -15.2   4.6  270   9  5   6.9   3.8 | -14.4   6.1  205   7  4   6.7   3.7
 18500 -14.1   6.6  275   9  5   8.4   4.6 | -13.4   7.9  195   7  4   6.9   3.8
 18000 -12.9   8.8  275   8  4   8.2   4.5 | -12.4   9.7  185   8  4   6.9   3.8
 17500 -11.6  11.1  280   7  4   8.2   4.5 | -11.3  11.7  180   8  4   7.1   3.9
 17000 -10.4  13.3  280   7  3   8.3   4.5 | -10.3  13.5  175   8  4   7.2   4.0
 16500  -9.2  15.4  285   6  3   8.3   4.6 |  -9.2  15.4  165   8  4   7.3   4.0
 16000  -7.9  17.8  285   5  3   8.7   4.8 |  -8.1  17.4  160   8  4   8.0   4.4
 15500  -6.6  20.1  280   4  2   8.7   4.8 |  -6.9  19.6  155   8  4   8.0   4.4
 15000  -4.8  23.4  265   2  1   8.3   4.5 |  -5.3  22.5  140   8  4   7.7   4.2
 14500  -3.5  25.7  230   1  1   8.3   4.5 |  -4.2  24.4  130   8  4   7.7   4.2
 14000  -2.4  27.7  165   1  1   7.9   4.3 |  -3.0  26.6  125   8  4   9.0   5.0
 13500  -1.3  29.7  135   3  1   7.9   4.3 |  -1.7  28.9  120   8  4   8.9   4.9
 13000  -0.1  31.8  125   4  2   9.0   5.0 |  -0.3  31.5  120   7  4  10.1   5.5
 12500   1.2  34.2  120   4  2   8.9   4.9 |   1.1  34.0  120   7  4  10.1   5.5
 12000   2.5  36.5  115   4  2   9.5   5.2 |   2.6  36.7  120   7  4   9.8   5.4
 11500   3.9  39.0  115   4  2   9.6   5.3 |   4.1  39.4  115   7  3   9.9   5.4
 11000   5.3  41.5  120   4  2   8.4   4.6 |   5.5  41.9  115   6  3   8.2   4.5
 10500   6.5  43.7  115   4  2   7.4   4.1 |   6.7  44.1  115   6  3   7.0   3.9
 10250   7.1  44.8  115   4  2  12.3   6.7 |   7.3  45.1  115   5  3  11.8   6.5
 10000   8.2  46.8  115   4  2  13.2   7.2 |   8.3  46.9  110   4  2  11.7   6.4
  9750   9.0  48.2  120   3  2   8.9   4.9 |   8.9  48.0  100   3  2   7.0   3.8
  9500   9.7  49.5  120   3  2  10.2   5.6 |   9.5  49.1  080   3  1   8.2   4.5
  9250  10.4  50.7  120   3  2   9.3   5.1 |  10.1  50.2  055   2  1   7.9   4.3
  9000  11.1  52.0  115   3  2   9.6   5.2 |  10.7  51.3  010   2  1   7.3   4.0
  8750  11.9  53.4  115   3  2  10.4   5.7 |  11.2  52.2  340   3  2   6.8   3.7
  8500  12.6  54.7  115   3  1  10.1   5.5 |  11.8  53.2  325   4  2   6.9   3.8
  8250  13.4  56.1  115   3  1  10.3   5.7 |  12.3  54.1  315   6  3   7.0   3.9
  8000  14.1  57.4  120   3  1  10.0   5.5 |  12.9  55.2  305   8  4   6.4   3.5
  7750  14.9  58.8  120   2  1   9.5   5.2 |  13.3  55.9  300  10  5   5.4   3.0
  7500  15.6  60.1  120   2  1   9.6   5.2 |  13.7  56.7  295  11  6   5.3   2.9
  7250  16.3  61.3  120   2  1  10.4   5.7 |  14.2  57.6  290  13  7   5.2   2.9
  7000  17.1  62.8  120   2  1  10.7   5.9 |  14.5  58.1  285  15  8   5.1   2.8
  6750  17.9  64.2  120   2  1   9.9   5.4 |  14.9  58.8  280  18  9   4.3   2.3
  6500  18.6  65.5  120   2  1  10.0   5.5 |  15.1  59.2  280  20 10   4.4   2.4
  6250  19.4  66.9  120   2  1  10.7   5.9 |  15.4  59.7  280  20 10   5.7   3.1
  6000  20.2  68.4  120   2  1  10.7   5.9 |  15.7  60.3  280  18  9   5.9   3.2
  5750  21.0  69.8  120   2  1  10.3   5.7 |  16.0  60.8  280  17  9   8.2   4.5
  5500  21.8  71.2  125   1  1  15.4   8.4 |  16.8  62.2  285  15  8  14.1   7.7
________________________________________________________________________________

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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