Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 060157
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1957 MDT Thursday, May 5, 2016

This forecast is for Friday, May 6, 2016:

If the trigger temperature of 76.8 F/24.9 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1250 ft/min (6.3 m/s)
   Maximum height of thermals.................. 18965 ft MSL (13658 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8988 ft MSL (3681 ft AGL)
Thermal soaring outlook for Saturday 05/07..... 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)................ Weak PVA
Potential height of wave....................... 25009 ft MSL (19702 ft AGL)
Wave soaring outlook for Saturday 05/07........ Poor

Remarks... Isolated afternoon thunderstorms

Sunrise/Sunset.................... 05:53:34 / 19:58:20 MDT
Total possible sunshine........... 14 hr 4 min 47 sec (844 min 47 sec)
Altitude of sun at 12:56:08 MDT... 67.04 degrees

Upper air data from numerical model forecast valid on 05/06/2016 at 0600 MDT

Freezing level.................. 13977 ft MSL (8670 ft AGL)
Convective condensation level... 17435 ft MSL (12128 ft AGL)
Lifted condensation level....... 17837 ft MSL (12531 ft AGL)
Lifted index.................... -0.3
K index......................... +16.9

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  -64.3 -83.7   245   33   17  -2.3  -1.3      M     M       M      M    M
 45000  -67.2 -89.0   230   43   22   2.8   1.5      M     M       M      M    M
 40000  -63.2 -81.8   225   29   15   2.4   1.3      M     M       M      M    M
 38000  -59.0 -74.2   215   27   14   8.0   4.4      M     M       M      M    M
 36000  -54.2 -65.6   210   27   14   8.0   4.4      M     M       M      M    M
 34000  -49.2 -56.6   205   24   12   8.6   4.7      M     M       M      M    M
 32000  -43.3 -45.9   200   17    9   8.6   4.7      M     M       M      M    M
 30000  -38.1 -36.6   195   15    8   8.9   4.9   36.9  98.5     6.9      M    M
 29000  -35.4 -31.7   200   15    8   8.9   4.9   36.6  97.9     6.7      M    M
 28000  -32.8 -27.0   200   16    8   8.9   4.9   36.4  97.5     6.6      M    M
 27000  -30.2 -22.4   200   17    9   8.3   4.5   35.9  96.6     6.3      M    M
 26000  -27.7 -17.9   205   18    9   8.3   4.5   35.3  95.5     5.9      M    M
 25000  -25.2 -13.4   210   19   10   8.2   4.5   34.8  94.6     5.6      M    M
 24000  -23.0  -9.4   210   19   10   6.1   3.3   33.9  93.1     5.0      M    M
 23000  -21.2  -6.2   205   17    9   6.2   3.4   32.6  90.6     3.8      M    M
 22000  -19.4  -2.9   200   15    8   6.2   3.4   31.3  88.4     2.8      M    M
 21000  -17.4   0.7   200   14    7   6.8   3.7   30.2  86.3     1.9      M    M
 20000  -15.4   4.3   200   14    7   6.8   3.8   29.1  84.4     0.9      M    M
 19500  -14.4   6.1   195   13    7   6.9   3.8   28.6  83.5     0.5      M    M
 19000  -13.4   7.9   195   13    7   7.1   3.9   28.2  82.7     0.1      M    M
 18500  -12.2  10.0   195   13    7   8.4   4.6   27.9  82.1    -0.2   1313  6.7
 18000  -11.0  12.2   195   13    7   8.4   4.6   27.6  81.7    -0.4   1262  6.4
 17500   -9.8  14.4   195   13    7   8.6   4.7   27.4  81.3    -0.7   1210  6.1
 17000   -7.9  17.8   200   12    6   8.7   4.8   27.1  80.8    -1.0   1130  5.7
 16500   -6.6  20.1   200   12    6   9.0   5.0   27.0  80.5    -1.1   1076  5.5
 16000   -5.2  22.6   210   12    6   9.1   5.0   26.8  80.3    -1.3   1021  5.2
 15500   -3.9  25.0   215   12    6   9.0   5.0   26.7  80.1    -1.4    966  4.9
 15000   -2.5  27.5   220   13    6   9.0   4.9   26.6  79.9    -1.5    911  4.6
 14500   -1.2  29.8   220   13    7   9.0   4.9   26.5  79.7    -1.6    856  4.3
 14000    0.1  32.2   225   13    7   9.0   4.9   26.3  79.4    -1.8    801  4.1
 13500    1.5  34.7   225   13    7   9.0   4.9   26.2  79.2    -1.9    746  3.8
 13000    2.8  37.0   230   13    7   9.1   5.0   26.1  79.0    -2.0    691  3.5
 12500    4.2  39.6   235   12    6   9.0   4.9   26.0  78.8    -2.1    635  3.2
 12000    5.6  42.1   235   13    7   9.9   5.4   25.9  78.7    -2.2    579  2.9
 11500    7.0  44.6   240   14    7  10.0   5.5   25.9  78.7    -2.2    520  2.6
 11000    8.4  47.1   245   15    8   8.0   4.4   25.8  78.5    -2.3    465  2.4
 10500    9.6  49.3   245   16    8   7.5   4.1   25.6  78.1    -2.6    414  2.1
 10250   10.2  50.4   245   17    9  10.5   5.7   25.5  77.8    -2.7    388  2.0
 10000   11.1  52.0   245   17    9  10.7   5.9   25.6  78.1    -2.6    353  1.8
  9750   11.8  53.2   240   17    9   7.9   4.3   25.5  77.9    -2.6    326  1.7
  9500   12.4  54.3   240   17    8   8.8   4.8   25.4  77.8    -2.7    300  1.5
  9250   13.1  55.6   240   16    8   8.0   4.4   25.3  77.6    -2.8    273  1.4
  9000   13.6  56.5   240   16    8   7.6   4.2   25.2  77.3    -3.0    249  1.3
  8750   14.2  57.6   240   15    8   7.9   4.3   25.0  77.0    -3.2    224  1.1
  8500   14.8  58.6   240   14    7   7.8   4.3   24.9  76.8    -3.3    199  1.0
  8250   15.4  59.7   240   14    7   7.9   4.3   24.7  76.5    -3.5    174  0.9
  8000   15.9  60.6   235   14    7   7.2   4.0   24.6  76.2    -3.7    150  0.8
  7750   16.4  61.5   235   14    7   6.4   3.5   24.3  75.8    -3.9    129  0.7
  7500   16.9  62.4   235   14    7   6.3   3.5   24.1  75.3    -4.2    108  0.5
  7250   17.3  63.1   235   13    7   6.6   3.6   23.8  74.9    -4.5     87  0.4
  7000   17.7  63.9   230   13    7   5.9   3.2   23.6  74.4    -4.8     66  0.3
  6750   18.2  64.8   230   13    7   7.4   4.0   23.3  73.9    -5.1     46  0.2
  6500   18.5  65.3   230   13    7  -1.8  -1.0   22.9  73.3    -5.5     28  0.1
  6250   17.7  63.9   235   13    7 -14.0  -7.7   21.4  70.6    -7.1     45  0.2
  6000   16.6  61.9   235   12    6 -12.7  -7.0   19.7  67.4    -8.9     70  0.4
  5750   15.5  59.9   240   12    6 -16.8  -9.2   17.9  64.3   -10.7     95  0.5
  5500   13.4  56.1   240   11    6 -42.9 -23.6   15.1  59.2   -13.6    152  0.8

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

           05/06/2016 at 0900 MDT          |       05/06/2016 at 1200 MDT
                                           |
K index... +22.8  LI... -1.2               | K index... +21.7  LI... -2.5
CAPE... +40.0  CIN... -16.2                | CAPE... +318.4  CIN... -34.6
                                           |
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 -63.3 -81.9  240  30 15  -1.9  -1.1 | -63.5 -82.3  240  30 15  -1.4  -0.8
 45000 -65.7 -86.3  230  44 23   1.9   1.0 | -65.2 -85.4  235  43 22   1.8   1.0
 40000 -63.1 -81.6  250  39 20   1.6   0.9 | -62.7 -80.9  245  44 23   1.6   0.9
 38000 -59.1 -74.4  240  33 17   7.9   4.3 | -59.0 -74.2  235  39 20   7.3   4.0
 36000 -54.4 -65.9  215  29 15   7.9   4.3 | -54.6 -66.3  220  33 17   7.3   4.0
 34000 -49.0 -56.2  205  27 14   8.1   4.5 | -49.2 -56.6  210  32 17   8.7   4.8
 32000 -44.1 -47.4  205  26 13   8.1   4.5 | -44.0 -47.2  205  34 17   8.7   4.8
 30000 -38.9 -38.0  205  24 12   8.9   4.9 | -38.9 -38.0  210  33 17   8.4   4.6
 29000 -36.2 -33.2  205  22 12   8.9   4.9 | -36.3 -33.3  210  32 17   8.4   4.6
 28000 -33.6 -28.5  205  21 11   8.9   4.9 | -33.8 -28.8  210  31 16   8.4   4.6
 27000 -31.0 -23.8  205  21 11   8.6   4.7 | -31.3 -24.3  210  30 15   8.5   4.7
 26000 -28.4 -19.1  210  22 11   8.5   4.7 | -28.8 -19.8  205  28 15   8.5   4.7
 25000 -25.8 -14.4  210  23 12   8.5   4.7 | -26.2 -15.2  205  27 14   8.5   4.7
 24000 -23.5 -10.3  215  22 12   6.7   3.7 | -23.8 -10.8  205  26 13   7.2   4.0
 23000 -21.5  -6.7  210  21 11   6.8   3.7 | -21.7  -7.1  205  25 13   7.3   4.0
 22000 -19.5  -3.1  210  19 10   6.8   3.7 | -19.5  -3.1  205  24 12   7.3   4.0
 21000 -17.6   0.3  205  17  9   6.3   3.5 | -17.5   0.5  205  23 12   6.3   3.4
 20000 -15.7   3.7  205  16  8   6.3   3.5 | -15.7   3.7  205  22 11   6.3   3.5
 19500 -14.8   5.4  200  16  8   6.3   3.5 | -14.8   5.4  205  21 11   6.4   3.5
 19000 -13.9   7.0  195  15  8   6.6   3.6 | -13.8   7.2  205  20 10   6.8   3.7
 18500 -12.8   9.0  195  15  8   8.3   4.6 | -12.7   9.1  205  20 10   8.4   4.6
 18000 -11.6  11.1  195  15  8   8.2   4.5 | -11.5  11.3  205  20 10   8.4   4.6
 17500 -10.3  13.5  195  15  8   8.9   4.9 | -10.3  13.5  200  20 10   8.7   4.8
 17000  -8.4  16.9  200  13  7   9.0   4.9 |  -8.3  17.1  195  19 10   8.7   4.8
 16500  -7.0  19.4  205  12  6   9.3   5.1 |  -7.0  19.4  190  19 10   9.5   5.2
 16000  -5.6  21.9  210  11  6   9.3   5.1 |  -5.5  22.1  190  18  9   9.5   5.2
 15500  -4.2  24.4  220  10  5   9.3   5.1 |  -4.1  24.6  190  17  9   9.2   5.0
 15000  -2.9  26.8  230   9  5   9.3   5.1 |  -2.8  27.0  190  15  8   8.9   4.9
 14500  -1.5  29.3  240   9  5   9.3   5.1 |  -1.5  29.3  190  14  7   8.9   4.9
 14000  -0.2  31.6  250   9  5   9.4   5.1 |  -0.1  31.8  185  13  7   9.1   5.0
 13500   1.2  34.2  260  10  5   9.4   5.1 |   1.2  34.2  185  12  6   9.1   5.0
 13000   2.6  36.7  265  10  5   9.3   5.1 |   2.6  36.7  190  12  6   9.8   5.4
 12500   4.0  39.2  270  11  6   9.3   5.1 |   4.1  39.4  195  11  6   9.8   5.4
 12000   5.4  41.7  270  12  6   9.5   5.2 |   5.5  41.9  200  11  6   9.2   5.0
 11500   6.8  44.2  265  12  6   9.7   5.3 |   6.9  44.4  205  11  5   9.3   5.1
 11000   8.1  46.6  260  12  6   7.2   4.0 |   8.1  46.6  215  11  5   8.2   4.5
 10500   9.2  48.6  260  13  7   6.5   3.6 |   9.4  48.9  220  11  6   7.9   4.3
 10250   9.7  49.5  260  13  7  10.8   5.9 |  10.0  50.0  220  11  6  10.7   5.9
 10000  10.7  51.3  260  13  7  11.4   6.3 |  10.9  51.6  225  11  6  10.9   6.0
  9750  11.3  52.3  260  13  7   7.5   4.1 |  11.5  52.7  225  11  6   8.3   4.5
  9500  12.0  53.6  255  13  7   8.9   4.9 |  12.2  54.0  225  11  6   9.3   5.1
  9250  12.6  54.7  255  13  7   7.4   4.0 |  12.8  55.0  230  11  6   7.9   4.3
  9000  13.1  55.6  255  13  7   7.7   4.2 |  13.3  55.9  230  10  5   7.5   4.1
  8750  13.8  56.8  255  13  7   9.1   5.0 |  13.9  57.0  230  10  5   8.4   4.6
  8500  14.5  58.1  255  13  7   8.7   4.8 |  14.5  58.1  230   9  4   8.2   4.5
  8250  15.1  59.2  255  12  6   9.1   5.0 |  15.1  59.2  230   8  4   7.7   4.2
  8000  15.8  60.4  255  11  6   8.6   4.7 |  15.7  60.3  230   6  3   7.5   4.1
  7750  16.4  61.5  255  11  5   7.8   4.3 |  16.2  61.2  230   5  2   7.7   4.2
  7500  17.0  62.6  255  10  5   7.1   3.9 |  16.8  62.2  230   3  2   8.1   4.4
  7250  17.5  63.5  255  10  5   5.5   3.0 |  17.4  63.3  225   3  1   9.2   5.0
  7000  17.8  64.0  255   9  5   4.3   2.4 |  18.1  64.6  225   2  1   9.8   5.4
  6750  18.1  64.6  255   9  4   4.7   2.6 |  18.8  65.8  225   2  1   9.8   5.4
  6500  18.4  65.1  255   8  4  -0.7  -0.4 |  19.6  67.3  230   2  1  10.5   5.8
  6250  18.0  64.4  255   7  4  -6.2  -3.4 |  20.4  68.7  235   1  1  11.2   6.2
  6000  17.4  63.3  255   7  3  -5.9  -3.2 |  21.2  70.2  235   1  1  10.8   5.9
  5750  16.8  62.2  255   6  3  -8.5  -4.7 |  22.0  71.6  240   1  1  11.2   6.1
  5500  16.1  61.0  240   5  2  -3.9  -2.2 |  23.0  73.4  240   1  1  16.9   9.3

           05/06/2016 at 1500 MDT          |       05/06/2016 at 1800 MDT
                                           |
K index... +24.2  LI... -2.0               | K index... +24.6  LI... -2.6
CAPE... +398.0  CIN... -14.4               | CAPE... +1045.8  CIN... -23.2
                                           |
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 -63.6 -82.5  240  27 14  -2.1  -1.2 | -62.3 -80.1  255  26 13  -2.2  -1.2
 45000 -66.4 -87.5  235  33 17   2.0   1.1 | -65.2 -85.4  235  31 16   2.1   1.1
 40000 -63.7 -82.7  240  45 23   1.7   0.9 | -62.4 -80.3  240  55 28   1.9   1.1
 38000 -60.0 -76.0  235  42 22   7.5   4.1 | -59.0 -74.2  235  56 29   6.8   3.7
 36000 -55.5 -67.9  230  38 19   7.5   4.1 | -54.9 -66.8  230  54 28   6.8   3.7
 34000 -50.5 -58.9  225  37 19   9.4   5.2 | -49.8 -57.6  225  52 27   8.5   4.6
 32000 -44.1 -47.4  225  40 21   9.4   5.2 | -44.7 -48.5  225  49 25   8.5   4.6
 30000 -38.4 -37.1  225  39 20   9.6   5.3 | -39.1 -38.4  220  46 24   9.9   5.4
 29000 -35.5 -31.9  220  38 19   9.6   5.3 | -36.1 -33.0  215  44 23   9.9   5.4
 28000 -32.6 -26.7  215  36 19   9.6   5.3 | -33.2 -27.8  215  43 22   9.9   5.4
 27000 -30.0 -22.0  215  36 18   7.8   4.3 | -30.6 -23.1  215  43 22   7.7   4.2
 26000 -27.7 -17.9  215  36 19   7.8   4.3 | -28.3 -18.9  215  44 23   7.6   4.2
 25000 -25.4 -13.7  215  36 19   7.8   4.3 | -26.0 -14.8  215  46 24   7.6   4.2
 24000 -23.1  -9.6  215  36 19   7.5   4.1 | -23.7 -10.7  215  46 24   7.7   4.2
 23000 -20.8  -5.4  210  35 18   7.5   4.1 | -21.4  -6.5  215  44 23   7.7   4.2
 22000 -18.6  -1.5  210  34 17   7.5   4.1 | -19.1  -2.4  215  42 22   7.7   4.2
 21000 -16.5   2.3  205  33 17   6.4   3.5 | -16.7   1.9  215  40 21   8.3   4.6
 20000 -14.6   5.7  210  32 16   6.4   3.5 | -14.2   6.4  210  38 20   8.4   4.6
 19500 -13.7   7.3  210  31 16   6.5   3.5 | -12.9   8.8  210  37 19   8.4   4.6
 19000 -12.8   9.0  210  31 16   6.7   3.7 | -11.7  10.9  210  36 19   8.3   4.6
 18500 -11.6  11.1  210  31 16   8.5   4.7 | -10.6  12.9  210  36 19   6.7   3.7
 18000 -10.4  13.3  210  31 16   8.4   4.6 |  -9.6  14.7  210  37 19   6.9   3.8
 17500  -9.2  15.4  210  31 16   8.7   4.8 |  -8.0  17.6  210  37 19   8.3   4.5
 17000  -7.2  19.0  205  28 14   8.9   4.9 |  -6.8  19.8  210  35 18   8.3   4.5
 16500  -6.0  21.2  200  25 13   8.3   4.6 |  -5.6  21.9  210  32 17   8.8   4.8
 16000  -4.8  23.4  200  24 12   8.3   4.5 |  -4.3  24.3  205  29 15   9.0   5.0
 15500  -3.6  25.5  195  22 11   8.1   4.5 |  -3.1  26.4  205  26 13   9.1   5.0
 15000  -2.4  27.7  190  20 10   8.0   4.4 |  -1.7  28.9  200  23 12   9.2   5.0
 14500  -1.3  29.7  180  18  9   8.0   4.4 |  -0.4  31.3  200  21 11   9.2   5.1
 14000  -0.1  31.8  175  17  9   8.4   4.6 |   0.9  33.6  190  19 10   9.4   5.2
 13500   1.1  34.0  170  16  8   8.3   4.6 |   2.3  36.1  185  19 10   9.5   5.2
 13000   2.4  36.3  170  15  8   9.2   5.0 |   3.6  38.5  180  20 10   8.4   4.6
 12500   3.8  38.8  170  14  7   9.1   5.0 |   4.9  40.8  175  21 11   8.4   4.6
 12000   5.1  41.2  165  14  7   9.7   5.3 |   6.1  43.0  170  22 11   8.9   4.9
 11500   6.6  43.9  165  13  7   9.8   5.4 |   7.5  45.5  170  22 11   9.1   5.0
 11000   7.9  46.2  165  13  7   8.4   4.6 |   8.8  47.8  170  22 12   7.9   4.4
 10500   9.2  48.6  165  12  6   8.6   4.7 |   9.9  49.8  170  22 11   7.8   4.3
 10250   9.9  49.8  165  12  6  12.3   6.8 |  10.5  50.9  170  22 11  11.0   6.0
 10000  10.9  51.6  165  12  6  12.0   6.6 |  11.4  52.5  170  21 11  10.9   6.0
  9750  11.6  52.9  165  12  6   9.2   5.1 |  12.0  53.6  170  21 11   8.7   4.8
  9500  12.4  54.3  165  11  6  10.1   5.5 |  12.7  54.9  175  21 11   9.2   5.0
  9250  13.1  55.6  165  11  6   9.2   5.1 |  13.4  56.1  175  20 10   9.6   5.3
  9000  13.8  56.8  170  11  6   9.3   5.1 |  14.1  57.4  175  20 10   9.7   5.3
  8750  14.5  58.1  170  11  5  10.1   5.6 |  14.8  58.6  175  19 10   9.3   5.1
  8500  15.2  59.4  170  10  5   9.6   5.3 |  15.5  59.9  175  19 10   9.0   4.9
  8250  16.0  60.8  170  10  5  10.8   5.9 |  16.2  61.2  175  19 10  10.4   5.7
  8000  16.8  62.2  170  10  5  10.8   5.9 |  17.0  62.6  175  19 10  10.4   5.7
  7750  17.6  63.7  170  10  5   9.5   5.2 |  17.7  63.9  175  18  9   8.8   4.8
  7500  18.3  64.9  170  10  5   9.7   5.3 |  18.3  64.9  175  18  9   8.7   4.8
  7250  19.0  66.2  170   9  5  10.1   5.5 |  19.0  66.2  175  18  9   9.9   5.4
  7000  19.8  67.6  170   9  5  10.1   5.6 |  19.8  67.6  175  17  9  10.8   5.9
  6750  20.5  68.9  170   9  5   9.0   5.0 |  20.5  68.9  175  17  9   9.6   5.3
  6500  21.2  70.2  170   9  4   9.4   5.2 |  21.2  70.2  175  16  8   9.4   5.2
  6250  21.9  71.4  175   8  4  10.9   6.0 |  21.9  71.4  175  16  8  10.1   5.5
  6000  22.8  73.0  175   8  4  11.3   6.2 |  22.7  72.9  180  15  8  10.4   5.7
  5750  23.6  74.5  175   8  4   9.8   5.4 |  23.4  74.1  180  14  7   9.5   5.2
  5500  24.3  75.7  175   7  4  12.8   7.0 |  24.0  75.2  180  12  6   8.7   4.8
________________________________________________________________________________

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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