Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 221311
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0711 MDT Sunday, May 22, 2016

This forecast is for Sunday, May 22, 2016:

If the trigger temperature of 75.3 F/24.1 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 875 ft/min (4.4 m/s)
   Maximum height of thermals.................. 15495 ft MSL (10210 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1145 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7084 ft MSL (1799 ft AGL)
Thermal soaring outlook for Monday 05/23....... Excellent

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... 15869 ft MSL (10584 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39497 ft MSL (34212 ft AGL)
Wave soaring outlook for Monday 05/23.......... Poor

Remarks... Large upper trough west of colorado with strengthening southwest flow
           aloft over the state.

Sunrise/Sunset.................... 05:38:54 / 20:13:20 MDT
Total possible sunshine........... 14 hr 34 min 26 sec (874 min 26 sec)
Altitude of sun at 12:56:19 MDT... 70.79 degrees

Upper air data from rawinsonde observation taken on 05/22/2016 at 0600 MDT

Freezing level.................. 13687 ft MSL (8402 ft AGL)
Convective condensation level... 19680 ft MSL (14395 ft AGL)
Lifted condensation level....... 17421 ft MSL (12136 ft AGL)
Lifted index.................... +3.3
K index......................... +8.2

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  -57.8 -72.0   255   52   27  -9.9  -5.4  101.7 215.1    43.8      M    M
 45000  -68.3 -90.9   215   41   21   8.4   4.6   58.0 136.4    20.1      M    M
 40000  -60.8 -77.4   235   59   30   6.2   3.4   47.0 116.5    14.2      M    M
 38000  -56.7 -70.1   225   61   31   7.7   4.2   44.3 111.8    12.8      M    M
 36000  -52.0 -61.6   225   58   30   8.8   4.8   42.7 108.9    12.0      M    M
 34000  -47.5 -53.5   220   54   28   5.5   3.0   40.9 105.6    11.0      M    M
 32000  -43.0 -45.4   210   51   26   8.5   4.7   38.9 101.9     9.8      M    M
 30000  -37.1 -34.8   210   51   26   8.8   4.9   38.0 100.4     9.5      M    M
 29000  -34.5 -30.1   210   51   26   8.8   4.9   37.6  99.6     9.2      M    M
 28000  -31.8 -25.2   210   51   26   8.8   4.9   37.2  99.0     9.1      M    M
 27000  -29.2 -20.6   210   51   26   8.5   4.7   36.9  98.4     8.9      M    M
 26000  -26.6 -15.9   210   51   26   8.6   4.7   36.4  97.6     8.7      M    M
 25000  -24.1 -11.4   210   51   26   8.6   4.7   36.1  97.0     8.5      M    M
 24000  -21.6  -6.9   210   49   25   8.0   4.4   35.5  95.9     8.1      M    M
 23000  -19.2  -2.6   215   47   24   8.1   4.4   34.8  94.6     7.6      M    M
 22000  -16.8   1.8   220   46   24   8.1   4.4   34.2  93.6     7.2      M    M
 21000  -14.5   5.9   220   44   23   6.8   3.7   33.6  92.4     6.7      M    M
 20000  -12.4   9.7   225   43   22   6.9   3.8   32.6  90.7     5.9      M    M
 19500  -11.4  11.5   225   43   22   6.3   3.5   32.1  89.8     5.5      M    M
 19000  -10.8  12.6   225   43   22   2.5   1.4   31.1  87.9     4.6      M    M
 18500  -10.6  12.9   225   43   22   2.3   1.2   29.8  85.6     3.4      M    M
 18000  -10.0  14.0   225   44   23   4.7   2.6   28.8  83.8     2.6      M    M
 17500   -9.3  15.3   225   43   22   4.7   2.6   27.9  82.2     1.8      M    M
 17000   -8.6  16.5   220   41   21   6.1   3.4   27.0  80.6     1.0      M    M
 16500   -7.2  19.0   220   40   20  10.4   5.7   26.9  80.4     0.9      M    M
 16000   -5.7  21.7   215   38   20   9.0   5.0   27.0  80.6     1.0      M    M
 15500   -5.1  22.8   215   36   18   2.9   1.6   26.0  78.8     0.1      M    M
 15000   -3.3  26.1   215   31   16   9.1   5.0   25.6  78.2    -0.2    910  4.6
 14500   -2.0  28.4   210   28   14   9.2   5.0   25.6  78.1    -0.3    854  4.3
 14000   -0.6  30.9   210   24   12   9.2   5.0   25.5  78.0    -0.3    798  4.1
 13500    0.8  33.4   210   20   10   9.2   5.0   25.5  77.8    -0.4    742  3.8
 13000    2.1  35.8   215   18    9   9.2   5.0   25.4  77.7    -0.5    687  3.5
 12500    3.5  38.3   220   20   11   9.2   5.0   25.3  77.5    -0.6    631  3.2
 12000    4.9  40.8   220   23   12   9.2   5.0   25.2  77.3    -0.7    575  2.9
 11500    6.2  43.2   220   22   11   9.2   5.0   25.0  77.1    -0.9    520  2.6
 11000    7.6  45.7   225   21   11   9.2   5.0   24.9  76.9    -1.0    464  2.4
 10500    9.0  48.2   225   20   10   9.2   5.1   24.8  76.7    -1.1    408  2.1
 10250    9.6  49.3   225   19   10   9.1   5.0   24.8  76.6    -1.2    380  1.9
 10000   10.3  50.5   230   20   10   8.9   4.9   24.7  76.5    -1.2    353  1.8
  9750   11.0  51.8   225   21   11   8.8   4.8   24.7  76.4    -1.3    326  1.7
  9500   11.6  52.9   220   22   12   8.8   4.9   24.6  76.3    -1.4    299  1.5
  9250   12.3  54.1   220   24   12   8.8   4.9   24.5  76.2    -1.4    272  1.4
  9000   12.9  55.2   215   25   13   8.8   4.9   24.5  76.1    -1.5    245  1.2
  8750   13.6  56.5   210   25   13   8.8   4.9   24.4  75.9    -1.6    218  1.1
  8500   14.2  57.6   210   24   13   8.9   4.9   24.3  75.8    -1.7    191  1.0
  8250   14.9  58.8   205   24   12   8.8   4.9   24.3  75.7    -1.8    164  0.8
  8000   15.6  60.1   205   24   12   8.9   4.9   24.2  75.6    -1.8    136  0.7
  7750   16.2  61.2   205   25   13   8.8   4.8   24.1  75.4    -1.9    109  0.6
  7500   16.9  62.4   210   25   13   9.0   5.0   24.0  75.3    -2.0     82  0.4
  7250   17.3  63.1   210   26   13   0.9   0.5   23.8  74.8    -2.3     61  0.3
  7000   17.0  62.6   210   27   14  -5.4  -3.0   22.7  72.9    -3.3     63  0.3
  6750   16.7  62.1   205   24   12  -3.5  -1.9   21.7  71.0    -4.4     66  0.3
  6500   16.4  61.5   205   20   11  -4.8  -2.7   20.6  69.1    -5.5     68  0.3
  6250   16.0  60.8   200   17    9  -1.3  -0.7   19.6  67.3    -6.5     71  0.4
  6000   16.0  60.8   190   14    7  -1.0  -0.6   18.9  66.0    -7.3     63  0.3
  5750   15.5  59.9   190    7    4  -4.3  -2.3   17.9  64.2    -8.6     72  0.4
  5500   14.6  58.3   000    0    0 -12.0  -6.6   16.7  62.0   -10.3     92  0.5

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

           05/22/2016 at 0900 MDT          |       05/22/2016 at 1200 MDT
                                           |
K index... -5.3  LI... +4.2                | K index... +3.1  LI... +3.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -62.2 -80.0  255  30 16  -3.3  -1.8 | -61.7 -79.1  260  19 10  -2.6  -1.4
 45000 -66.5 -87.7  240  55 28   4.2   2.3 | -65.1 -85.2  240  31 16   3.4   1.9
 40000 -60.7 -77.3  235  62 32   3.2   1.7 | -60.6 -77.1  230  59 30   2.4   1.3
 38000 -56.4 -69.5  235  60 31   7.7   4.2 | -56.4 -69.5  225  59 30   7.8   4.3
 36000 -51.8 -61.2  230  57 30   7.7   4.2 | -51.7 -61.1  225  57 29   7.8   4.3
 34000 -47.1 -52.8  225  55 29   8.0   4.4 | -47.0 -52.6  220  57 29   7.8   4.3
 32000 -42.3 -44.1  220  54 28   8.0   4.4 | -42.4 -44.3  220  58 30   7.8   4.3
 30000 -37.5 -35.5  215  53 27   8.2   4.5 | -37.2 -35.0  220  58 30   7.7   4.2
 29000 -34.4 -29.9  215  53 28   8.2   4.5 | -34.9 -30.8  220  58 30   7.7   4.2
 28000 -32.0 -25.6  215  54 28   8.2   4.5 | -32.6 -26.7  220  58 30   7.7   4.2
 27000 -29.6 -21.3  215  53 27   7.6   4.1 | -30.3 -22.5  220  57 29   7.6   4.2
 26000 -27.4 -17.3  215  51 26   7.6   4.1 | -28.0 -18.4  220  56 29   7.6   4.2
 25000 -25.1 -13.2  220  50 26   7.6   4.2 | -25.7 -14.3  220  55 28   7.7   4.2
 24000 -22.9  -9.2  215  49 25   7.6   4.1 | -23.5 -10.3  220  54 28   7.5   4.1
 23000 -20.6  -5.1  215  47 24   7.6   4.1 | -21.2  -6.2  220  53 27   7.6   4.1
 22000 -18.4  -1.1  215  46 24   7.6   4.1 | -19.0  -2.2  220  53 27   7.6   4.2
 21000 -16.2   2.8  210  46 23   7.3   4.0 | -16.8   1.8  215  51 26   7.0   3.8
 20000 -14.0   6.8  210  45 23   7.3   4.0 | -14.7   5.5  215  50 26   7.0   3.9
 19500 -12.9   8.8  210  45 23   7.3   4.0 | -13.7   7.3  215  49 25   7.0   3.9
 19000 -11.8  10.8  205  45 23   7.3   4.0 | -12.6   9.3  210  49 25   6.9   3.8
 18500 -10.7  12.7  205  44 23   7.6   4.2 | -11.5  11.3  210  48 25   8.3   4.5
 18000  -9.6  14.7  205  44 23   7.6   4.2 | -10.3  13.5  210  46 24   8.2   4.5
 17500  -8.5  16.7  205  45 23   7.8   4.3 |  -9.0  15.8  210  45 23   8.5   4.6
 17000  -7.3  18.9  205  45 23   7.9   4.3 |  -7.7  18.1  210  45 23   8.8   4.8
 16500  -6.1  21.0  205  45 23   7.9   4.3 |  -6.4  20.5  210  44 23   8.8   4.8
 16000  -5.0  23.0  205  45 23   7.7   4.3 |  -5.1  22.8  210  44 23   8.5   4.7
 15500  -3.2  26.2  210  44 23   7.6   4.2 |  -3.2  26.2  215  45 23   8.4   4.6
 15000  -2.1  28.2  210  43 22   7.3   4.0 |  -2.0  28.4  215  45 23   7.5   4.1
 14500  -1.0  30.2  215  42 21   7.3   4.0 |  -0.9  30.4  220  46 24   7.7   4.2
 14000   0.1  32.2  215  40 21   7.1   3.9 |   0.1  32.2  225  46 23   6.0   3.3
 13500   1.1  34.0  215  38 20   7.1   3.9 |   1.0  33.8  225  44 23   6.3   3.5
 13000   2.2  36.0  220  36 19   6.9   3.8 |   1.8  35.2  230  41 21   4.3   2.4
 12500   3.2  37.8  225  35 18   6.8   3.7 |   2.4  36.3  230  35 18   4.1   2.3
 12000   4.3  39.7  225  34 18   8.0   4.4 |   3.0  37.4  225  30 15   5.0   2.7
 11500   5.5  41.9  230  36 19   8.4   4.6 |   3.8  38.8  220  24 12   5.2   2.9
 11000   6.6  43.9  235  37 19   3.9   2.2 |   4.5  40.1  210  19 10   5.7   3.2
 10500   6.9  44.4  235  32 16   2.6   1.4 |   5.4  41.7  195  16  8   5.0   2.8
 10250   7.1  44.8  240  29 15   2.3   1.3 |   5.8  42.4  190  15  8   9.8   5.4
 10000   7.3  45.1  240  23 12   3.6   2.0 |   6.7  44.1  180  14  7  11.5   6.3
  9750   7.6  45.7  240  21 11   4.8   2.6 |   7.3  45.1  180  13  7   8.1   4.4
  9500   7.9  46.2  235  18  9   4.3   2.4 |   8.0  46.4  175  12  6   8.9   4.9
  9250   8.2  46.8  235  15  8   5.3   2.9 |   8.6  47.5  170  12  6   9.2   5.1
  9000   8.6  47.5  230  13  7   6.3   3.5 |   9.3  48.7  170  11  6  10.1   5.5
  8750   9.0  48.2  225  11  6   6.4   3.5 |  10.1  50.2  170  11  6  10.1   5.6
  8500   9.5  49.1  215   8  4   5.9   3.2 |  10.8  51.4  165  11  6  10.0   5.5
  8250   9.9  49.8  200   6  3   8.1   4.4 |  11.6  52.9  165  11  5  10.6   5.8
  8000  10.6  51.1  185   5  3   9.8   5.4 |  12.4  54.3  165  10  5  10.5   5.8
  7750  11.2  52.2  170   5  2   8.1   4.4 |  13.1  55.6  165  10  5   9.5   5.2
  7500  11.8  53.2  155   4  2   7.7   4.2 |  13.9  57.0  165  10  5   9.3   5.1
  7250  12.4  54.3  140   5  2   8.0   4.4 |  14.6  58.3  165  10  5   9.9   5.4
  7000  13.0  55.4  125   5  2   8.1   4.4 |  15.3  59.5  165   9  5  10.4   5.7
  6750  13.6  56.5  110   5  3   7.1   3.9 |  16.0  60.8  165   9  5   9.3   5.1
  6500  14.0  57.2  100   6  3   6.4   3.5 |  16.7  62.1  165   9  5   9.5   5.2
  6250  14.5  58.1  100   6  3   6.4   3.5 |  17.5  63.5  165   9  4  11.2   6.1
  6000  14.9  58.8  100   5  3   6.3   3.4 |  18.4  65.1  160   8  4  12.4   6.8
  5750  15.3  59.5  100   5  3   7.3   4.0 |  19.3  66.7  160   8  4   9.2   5.0
  5500  15.9  60.6  110   4  2  13.4   7.3 |  19.9  67.8  160   7  4  12.3   6.8

           05/22/2016 at 1500 MDT          |       05/22/2016 at 1800 MDT
                                           |
K index... +14.8  LI... +2.7               | K index... +20.3  LI... -0.5
CAPE... 0.0  CIN... -1.1                   | CAPE... +4.6  CIN... -29.5
                                           |
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 -61.4 -78.5  245  18  9  -1.9  -1.0 | -60.7 -77.3  245  20 10  -1.7  -0.9
 45000 -63.7 -82.7  235  33 17   2.1   1.2 | -62.8 -81.0  240  34 17   1.7   1.0
 40000 -60.3 -76.5  230  60 31   2.1   1.1 | -60.0 -76.0  230  58 30   1.7   0.9
 38000 -56.5 -69.7  225  61 31   7.3   4.0 | -56.2 -69.2  230  59 30   7.4   4.1
 36000 -52.1 -61.8  225  60 31   7.3   4.0 | -51.8 -61.2  225  58 30   7.4   4.1
 34000 -47.6 -53.7  220  59 30   7.8   4.3 | -47.2 -53.0  225  57 29   7.8   4.3
 32000 -42.9 -45.2  220  60 31   7.8   4.3 | -42.6 -44.7  225  57 29   7.8   4.3
 30000 -37.6 -35.7  220  60 31   7.8   4.3 | -37.2 -35.0  230  56 29   8.0   4.4
 29000 -35.3 -31.5  220  60 31   7.8   4.3 | -34.8 -30.6  230  56 29   8.0   4.4
 28000 -33.0 -27.4  220  59 31   7.8   4.3 | -32.4 -26.3  230  56 29   8.0   4.4
 27000 -30.6 -23.1  220  59 30   7.9   4.3 | -30.2 -22.4  230  56 29   6.9   3.8
 26000 -28.2 -18.8  220  59 30   7.9   4.4 | -28.1 -18.6  235  56 29   6.9   3.8
 25000 -25.9 -14.6  220  58 30   7.9   4.4 | -26.1 -15.0  235  56 29   6.9   3.8
 24000 -23.5 -10.3  225  57 30   8.2   4.5 | -23.9 -11.0  235  56 29   7.8   4.3
 23000 -21.0  -5.8  225  57 29   8.2   4.5 | -21.6  -6.9  240  56 29   7.8   4.3
 22000 -18.6  -1.5  225  56 29   8.2   4.5 | -19.3  -2.7  240  55 29   7.8   4.3
 21000 -16.2   2.8  225  55 29   7.6   4.2 | -17.2   1.0  240  54 28   6.0   3.3
 20000 -14.0   6.8  225  55 28   7.6   4.2 | -15.4   4.3  245  49 25   6.2   3.4
 19500 -12.8   9.0  230  54 28   7.6   4.2 | -14.5   5.9  245  46 24   6.2   3.4
 19000 -11.7  10.9  230  54 28   7.7   4.2 | -13.6   7.5  245  44 23   6.1   3.3
 18500 -10.7  12.7  230  53 27   6.4   3.5 | -12.6   9.3  245  41 21   8.4   4.6
 18000  -9.7  14.5  230  52 27   6.5   3.5 | -11.3  11.7  245  39 20   8.4   4.6
 17500  -8.8  16.2  230  51 26   6.2   3.4 | -10.1  13.8  240  36 19   8.5   4.7
 17000  -7.9  17.8  230  47 24   5.7   3.1 |  -8.8  16.2  240  35 18   8.7   4.8
 16500  -7.1  19.2  230  44 23   5.6   3.1 |  -7.5  18.5  235  33 17   8.8   4.8
 16000  -5.8  21.6  225  37 19   6.2   3.4 |  -6.3  20.7  235  32 16   8.1   4.4
 15500  -4.9  23.2  220  32 17   6.4   3.5 |  -4.5  23.9  225  31 16   8.2   4.5
 15000  -3.8  25.2  210  28 14   7.8   4.3 |  -3.2  26.2  225  30 15   8.9   4.9
 14500  -2.7  27.1  205  24 13   7.5   4.1 |  -1.9  28.6  220  29 15   8.8   4.8
 14000  -1.5  29.3  200  22 11   9.2   5.0 |  -0.6  30.9  215  29 15   9.5   5.2
 13500  -0.1  31.8  195  20 10   9.1   5.0 |   0.8  33.4  215  28 14   9.5   5.2
 13000   1.3  34.3  190  19 10   9.5   5.2 |   2.3  36.1  215  28 14   9.6   5.2
 12500   2.7  36.9  190  18  9   9.5   5.2 |   3.7  38.7  210  27 14   9.6   5.3
 12000   4.1  39.4  190  17  9   9.8   5.3 |   5.1  41.2  210  26 13   9.7   5.3
 11500   5.6  42.1  190  17  9   9.8   5.4 |   6.6  43.9  210  26 13   9.7   5.3
 11000   7.0  44.6  190  16  8   9.3   5.1 |   8.0  46.4  205  25 13   9.1   5.0
 10500   8.3  46.9  190  16  8   8.8   4.8 |   9.3  48.7  205  24 12   8.7   4.8
 10250   9.1  48.4  190  16  8  11.4   6.2 |  10.0  50.0  205  24 12  10.9   6.0
 10000  10.0  50.0  190  15  8  11.6   6.4 |  10.9  51.6  205  24 12  11.3   6.2
  9750  10.7  51.3  190  15  8   9.6   5.3 |  11.6  52.9  200  23 12   9.9   5.4
  9500  11.5  52.7  190  15  8  10.5   5.7 |  12.4  54.3  200  23 12  10.8   5.9
  9250  12.2  54.0  190  15  8   9.1   5.0 |  13.1  55.6  200  23 12   8.6   4.7
  9000  12.9  55.2  190  15  7   9.0   4.9 |  13.7  56.7  200  22 12   8.3   4.5
  8750  13.6  56.5  190  14  7  10.2   5.6 |  14.5  58.1  200  22 11  10.3   5.6
  8500  14.4  57.9  190  14  7   9.5   5.2 |  15.2  59.4  200  22 11   9.2   5.1
  8250  15.1  59.2  190  14  7  11.0   6.0 |  15.9  60.6  200  21 11  11.4   6.2
  8000  16.0  60.8  190  14  7  10.9   6.0 |  16.8  62.2  200  20 11  11.2   6.2
  7750  16.7  62.1  190  13  7   9.3   5.1 |  17.5  63.5  200  20 10   8.9   4.9
  7500  17.4  63.3  190  13  7   9.3   5.1 |  18.2  64.8  200  19 10   9.1   5.0
  7250  18.1  64.6  190  13  7   9.9   5.4 |  18.9  66.0  200  19 10   9.4   5.1
  7000  18.9  66.0  195  13  6  10.5   5.8 |  19.6  67.3  200  18 10   9.9   5.4
  6750  19.7  67.5  195  12  6   9.9   5.4 |  20.3  68.5  200  18  9   9.8   5.4
  6500  20.4  68.7  195  12  6   9.5   5.2 |  21.0  69.8  200  17  9   9.5   5.2
  6250  21.1  70.0  195  12  6  10.7   5.9 |  21.8  71.2  200  17  9   9.8   5.4
  6000  22.0  71.6  195  11  6  12.0   6.6 |  22.5  72.5  200  16  8  10.0   5.5
  5750  22.8  73.0  195  11  6  10.9   6.0 |  23.3  73.9  200  14  7  10.5   5.8
  5500  23.7  74.7  195  10  5  15.4   8.4 |  24.1  75.4  200  12  6  12.7   7.0
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613



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