Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 191309
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0609 MST Sunday, February 19, 2017

This forecast is for Sunday, February 19, 2017:

If the trigger temperature of 60.5 F/15.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 586 ft/min (3.0 m/s)
   Maximum height of thermals.................. 14404 ft MSL (9119 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... 1045 MST
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................. 10263 ft MSL (4978 ft AGL)
Thermal soaring outlook for Monday 02/20....... Good

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1700 MST)......... Becoming poor by 1200
Height of stable layer (12-18K ft MSL)......... 15873 ft MSL (10588 ft AGL)
Weak PVA/NVA (through 1700 MST)................ Weak PVA
Potential height of wave....................... 18089 ft MSL (12804 ft AGL)
Wave soaring outlook for Monday 02/20.......... Good

Remarks...

Sunrise/Sunset.................... 06:46:02 / 17:40:29 MST
Total possible sunshine........... 10 hr 54 min 27 sec (654 min 27 sec)
Altitude of sun at 12:13:15 MST... 39.14 degrees

Upper air data from rawinsonde observation taken on 02/19/2017 at 0500 MST

Freezing level.................. 10831 ft MSL (5546 ft AGL)
Convective condensation level... 16742 ft MSL (11457 ft AGL)
Lifted condensation level....... 15387 ft MSL (10102 ft AGL)
Lifted index.................... +0.7
K index......................... +12.5

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  -60.3 -76.5   210   35   18   5.4   2.9   97.5 207.5    44.8      M    M
 45000  -51.7 -61.1   215   56   29   7.8   4.3   86.1 186.9    41.1      M    M
 40000  -47.6 -53.7   215   44   23   2.3   1.3   69.6 157.2    33.0      M    M
 38000  -45.3 -49.5   220   67   35   4.2   2.3   64.1 147.3    30.2      M    M
 36000  -48.8 -55.8   205   93   48 -18.8 -10.3   50.5 122.9    21.5      M    M
 34000  -52.0 -61.6   200   70   36   4.8   2.7   37.6  99.7    13.0      M    M
 32000  -50.0 -58.0   205   60   31   1.3   0.7   32.2  90.0     9.4      M    M
 30000  -46.7 -52.1   205   60   31   8.0   4.4   28.0  82.4     6.4      M    M
 29000  -44.1 -47.4   200   59   30   9.5   5.2   27.5  81.5     6.1      M    M
 28000  -41.3 -42.3   195   58   30   9.5   5.2   27.4  81.4     6.2      M    M
 27000  -38.4 -37.1   200   55   28   9.5   5.2   27.3  81.1     6.1      M    M
 26000  -35.6 -32.1   200   52   27   9.5   5.2   27.2  80.9     6.1      M    M
 25000  -32.7 -26.9   205   49   25   9.5   5.2   27.1  80.8     6.1      M    M
 24000  -29.9 -21.8   205   48   25   9.5   5.2   26.9  80.5     6.0      M    M
 23000  -27.1 -16.8   205   48   25   9.2   5.0   26.6  80.0     5.9      M    M
 22000  -24.4 -11.9   205   47   24   9.2   5.0   26.4  79.5     5.7      M    M
 21000  -21.6  -6.9   210   47   24   9.2   5.0   26.2  79.2     5.7      M    M
 20000  -18.9  -2.0   210   47   24   9.2   5.0   26.2  79.2     5.7      M    M
 19500  -17.5   0.5   215   49   25   9.2   5.1   26.1  78.9     5.6      M    M
 19000  -16.1   3.0   220   51   26   9.7   5.3   25.9  78.7     5.5      M    M
 18500  -15.2   4.6   225   54   28   0.4   0.2   25.3  77.6     5.0      M    M
 18000  -14.9   5.2   225   57   29   5.3   2.9   24.0  75.2     3.9      M    M
 17500  -13.8   7.2   225   55   28  10.1   5.6   23.6  74.6     3.5      M    M
 17000  -12.3   9.9   225   53   27   9.7   5.3   23.6  74.5     3.5      M    M
 16500  -10.9  12.4   225   50   26   9.9   5.5   23.6  74.5     3.5      M    M
 16000   -9.8  14.4   225   48   25  -0.1  -0.0   23.2  73.8     3.2      M    M
 15500   -9.8  14.4   230   43   22   9.8   5.4   20.8  69.5     1.0      M    M
 15000   -8.6  16.5   230   41   21   9.2   5.1   20.6  69.1     0.8      M    M
 14500   -7.9  17.8   235   38   20  -3.7  -2.1   19.7  67.5    -0.0    786  4.0
 14000   -7.6  18.3   235   36   18   9.8   5.4   18.6  65.4    -1.1    761  3.9
 13500   -6.4  20.5   240   33   17   8.3   4.6   18.3  64.9    -1.4    710  3.6
 13000   -5.2  22.6   240   31   16   8.2   4.5   18.0  64.5    -1.6    658  3.3
 12500   -3.9  25.0   245   30   15   8.2   4.5   17.8  64.1    -1.9    607  3.1
 12000   -2.7  27.1   250   27   14   8.2   4.5   17.6  63.7    -2.1    556  2.8
 11500   -1.5  29.3   245   24   12   8.2   4.5   17.4  63.3    -2.3    504  2.6
 11000   -0.3  31.5   235   21   11   8.2   4.5   17.1  62.9    -2.6    453  2.3
 10500    0.9  33.6   235   20   10   8.3   4.5   16.9  62.4    -2.9    402  2.0
 10250    1.5  34.7   230   20   10   8.3   4.5   16.7  62.1    -3.0    376  1.9
 10000    2.1  35.8   230   19   10   8.3   4.5   16.6  61.9    -3.2    350  1.8
  9750    2.8  37.0   230   19   10   8.4   4.6   16.5  61.7    -3.3    325  1.6
  9500    3.4  38.1   230   18    9   8.5   4.7   16.4  61.5    -3.4    298  1.5
  9250    4.0  39.2   235   17    9   8.5   4.6   16.3  61.4    -3.5    272  1.4
  9000    4.6  40.3   235   16    8   8.5   4.6   16.2  61.2    -3.6    246  1.2
  8750    5.3  41.5   230   16    8   8.5   4.6   16.1  61.0    -3.7    220  1.1
  8500    5.9  42.6   230   16    8   8.5   4.6   16.0  60.9    -3.8    193  1.0
  8250    6.5  43.7   225   16    8   8.5   4.6   15.9  60.7    -3.9    167  0.8
  8000    7.2  45.0   225   16    8   8.5   4.7   15.9  60.5    -4.0    141  0.7
  7750    7.8  46.0   220   16    8   8.5   4.6   15.7  60.3    -4.2    115  0.6
  7500    8.4  47.1   210   17    9   8.5   4.7   15.6  60.1    -4.3     88  0.4
  7250    9.0  48.2   205   17    9   8.4   4.6   15.5  60.0    -4.4     62  0.3
  7000    9.7  49.5   200   18    9   8.9   4.9   15.4  59.8    -4.5     36  0.2
  6750   10.3  50.5   200   18    9   7.0   3.9   15.3  59.6    -4.6     10  0.0
  6500   10.9  51.6   200   18   10  13.9   7.6   15.2  59.4    -4.8      M    M
  6250   11.6  52.9   200   19   10 -11.9  -6.5   15.1  59.2    -4.9      M    M
  6000    9.6  49.3   200   19   10 -21.0 -11.5   12.4  54.3    -7.6      9  0.0
  5750    9.2  48.6   195   14    7   1.4   0.7   11.3  52.3    -8.7     13  0.1
  5500    8.4  47.1   190    9    5 -29.8 -16.3    9.8  49.6   -10.3     29  0.1

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

           02/19/2017 at 0800 MST          |       02/19/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +3.4        | CAPE...     0.0    LI...       +2.5
CINH...     0.0    K Index... +12.2        | CINH...     0.0    K Index... +14.9
                                           |
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 -59.0 -74.2  220  17  9   4.6   2.5 | -57.9 -72.2  225  18  9   4.6   2.5
 45000 -52.0 -61.6  210  26 13   1.5   0.8 | -51.1 -60.0  215  24 12   1.3   0.7
 40000 -49.2 -56.6  210  30 15   1.8   1.0 | -49.0 -56.2  205  29 15   1.4   0.8
 38000 -49.0 -56.2  210  33 17  -1.2  -0.7 | -48.9 -56.0  205  32 17  -1.3  -0.7
 36000 -49.7 -57.5  205  37 19  -1.2  -0.7 | -49.7 -57.5  200  37 19  -1.3  -0.7
 34000 -50.3 -58.5  205  41 21   2.4   1.3 | -50.1 -58.2  200  41 21   4.7   2.6
 32000 -47.8 -54.0  200  41 21   3.7   2.1 | -47.5 -53.5  200  43 22   4.2   2.3
 30000 -45.1 -49.2  200  40 21   8.1   4.5 | -44.6 -48.3  195  45 23   8.7   4.8
 29000 -42.8 -45.0  200  38 20   7.9   4.3 | -42.1 -43.8  195  44 22   8.4   4.6
 28000 -40.4 -40.7  200  36 19   7.9   4.3 | -39.6 -39.3  195  43 22   8.4   4.6
 27000 -38.0 -36.4  195  34 18   8.0   4.4 | -37.1 -34.8  190  42 21   8.4   4.6
 26000 -35.5 -31.9  195  32 17   8.3   4.6 | -34.7 -30.5  190  39 20   8.1   4.4
 25000 -33.1 -27.6  195  30 16   8.4   4.6 | -32.3 -26.1  190  37 19   8.1   4.4
 24000 -30.6 -23.1  195  29 15   8.4   4.6 | -29.8 -21.6  190  35 18   8.2   4.5
 23000 -28.1 -18.6  195  27 14   8.4   4.6 | -27.6 -17.7  190  32 16   7.5   4.1
 22000 -25.6 -14.1  195  26 14   8.4   4.6 | -25.3 -13.5  190  29 15   7.5   4.1
 21000 -23.1  -9.6  200  25 13   8.3   4.6 | -23.1  -9.6  190  27 14   7.5   4.1
 20000 -20.6  -5.1  200  25 13   8.2   4.5 | -21.0  -5.8  190  25 13   7.1   3.9
 19500 -19.4  -2.9  200  24 13   8.2   4.5 | -19.9  -3.8  195  25 13   7.1   3.9
 19000 -18.2  -0.8  200  24 12   8.2   4.5 | -18.3  -0.9  195  24 12   7.1   3.9
 18500 -17.0   1.4  200  24 12   8.2   4.5 | -17.3   0.9  195  23 12   7.0   3.8
 18000 -15.3   4.5  200  23 12   7.6   4.2 | -16.3   2.7  200  23 12   6.9   3.8
 17500 -14.2   6.4  200  22 12   7.6   4.2 | -15.2   4.6  200  23 12   6.9   3.8
 17000 -13.0   8.6  205  22 11   7.8   4.3 | -14.2   6.4  200  22 11   7.2   4.0
 16500 -11.9  10.6  205  21 11   7.8   4.3 | -13.1   8.4  200  22 11   7.2   3.9
 16000 -10.7  12.7  205  21 11   7.9   4.3 | -12.0  10.4  200  21 11   7.6   4.2
 15500  -9.5  14.9  205  20 11   7.9   4.3 | -10.9  12.4  200  20 10   7.8   4.3
 15000  -8.3  17.1  205  20 10   7.5   4.1 |  -9.7  14.5  200  19 10   7.8   4.3
 14500  -7.3  18.9  210  19 10   7.2   3.9 |  -8.5  16.7  200  19 10   7.9   4.3
 14000  -6.2  20.8  210  19 10   7.1   3.9 |  -7.4  18.7  200  18  9   7.8   4.3
 13500  -5.2  22.6  215  17  9   6.8   3.7 |  -6.3  20.7  200  17  9   7.4   4.0
 13000  -4.2  24.4  215  16  8   6.8   3.8 |  -5.2  22.6  200  16  8   7.4   4.1
 12500  -3.1  26.4  215  14  7   7.4   4.1 |  -4.1  24.6  200  16  8   7.2   4.0
 12000  -2.0  28.4  220  13  6   7.4   4.1 |  -3.0  26.6  200  15  8   7.2   4.0
 11500  -0.9  30.4  220  11  6   6.8   3.7 |  -1.9  28.6  200  14  7   7.6   4.2
 11000   0.1  32.2  220   9  5   6.8   3.7 |  -0.8  30.6  200  13  7   7.6   4.2
 10500   1.1  34.0  220   7  4   7.3   4.0 |   0.3  32.5  200  13  7   6.7   3.7
 10250   1.7  35.1  220   6  3   7.5   4.1 |   0.8  33.4  200  12  6   7.6   4.2
 10000   2.3  36.1  220   6  3   8.4   4.6 |   1.4  34.5  200  12  6   9.5   5.2
  9750   2.9  37.2  215   5  2   8.5   4.7 |   2.1  35.8  200  11  6   9.3   5.1
  9500   3.5  38.3  215   4  2   8.0   4.4 |   2.8  37.0  200  11  5   8.6   4.7
  9250   4.1  39.4  215   4  2   8.8   4.8 |   3.5  38.3  195  10  5   9.1   5.0
  9000   4.7  40.5  215   3  2   6.3   3.5 |   4.1  39.4  195  10  5   7.8   4.3
  8750   5.1  41.2  210   3  2   5.4   3.0 |   4.6  40.3  195   9  5   7.5   4.1
  8500   5.6  42.1  210   3  2   7.1   3.9 |   5.3  41.5  195   9  4   8.5   4.7
  8250   6.1  43.0  215   3  2   6.9   3.8 |   5.9  42.6  190   8  4   8.4   4.6
  8000   6.6  43.9  215   3  2   6.1   3.4 |   6.5  43.7  190   8  4   7.9   4.3
  7750   7.0  44.6  220   3  1   5.2   2.8 |   7.1  44.8  185   7  4   8.6   4.7
  7500   7.3  45.1  220   3  1   5.4   2.9 |   7.8  46.0  180   7  4   9.6   5.3
  7250   7.7  45.9  220   3  2   5.3   2.9 |   8.5  47.3  180   7  3   9.6   5.3
  7000   8.1  46.6  220   3  2   5.2   2.9 |   9.2  48.6  175   6  3   8.2   4.5
  6750   8.4  47.1  220   3  2   2.5   1.4 |   9.8  49.6  180   6  3   7.9   4.3
  6500   8.5  47.3  215   3  2   1.4   0.8 |  10.4  50.7  180   6  3   9.1   5.0
  6250   8.6  47.5  215   4  2  -0.5  -0.3 |  11.1  52.0  180   6  3   8.5   4.7
  6000   8.4  47.1  210   4  2  -5.3  -2.9 |  11.7  53.1  180   5  3   8.5   4.7
  5750   7.9  46.2  210   5  2  -7.4  -4.0 |  12.3  54.1  180   5  3   7.3   4.0
  5500   7.1  44.8  210   5  2 -13.9  -7.6 |  12.9  55.2  180   4  2  11.1   6.1

           02/19/2017 at 1400 MST          |       02/19/2017 at 1700 MST
                                           |
CAPE...   +15.2    LI...       +1.2        | CAPE...   +37.7    LI...       -0.3
CINH...    -1.6    K Index... +13.8        | CINH...   -24.0    K Index... +18.6
                                           |
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 -57.6 -71.7  225  17  9   4.6   2.5 | -57.4 -71.3  235  15  8   4.7   2.6
 45000 -50.9 -59.6  225  21 11   1.9   1.1 | -50.5 -58.9  235  16  8   2.6   1.4
 40000 -47.9 -54.2  210  25 13   2.0   1.1 | -46.6 -51.9  225  17  9   2.6   1.4
 38000 -47.8 -54.0  205  29 15  -1.8  -1.0 | -46.1 -51.0  215  19 10  -1.2  -0.7
 36000 -48.8 -55.8  200  36 19  -1.8  -1.0 | -46.8 -52.2  205  25 13  -1.2  -0.7
 34000 -49.6 -57.3  200  44 22   5.2   2.9 | -47.3 -53.1  200  32 16   3.7   2.1
 32000 -46.9 -52.4  195  47 24   4.5   2.5 | -45.1 -49.2  195  40 20   3.7   2.0
 30000 -43.9 -47.0  190  50 26   8.1   4.5 | -42.8 -45.0  195  47 24   6.3   3.4
 29000 -41.6 -42.9  195  48 25   7.8   4.3 | -40.9 -41.6  195  45 23   6.4   3.5
 28000 -39.3 -38.7  195  47 24   7.8   4.3 | -39.0 -38.2  195  43 22   6.4   3.5
 27000 -36.9 -34.4  195  45 23   7.8   4.3 | -37.1 -34.8  200  41 21   6.4   3.5
 26000 -34.7 -30.5  190  42 22   7.4   4.1 | -35.2 -31.4  200  37 19   6.3   3.5
 25000 -32.5 -26.5  190  39 20   7.4   4.1 | -33.3 -27.9  200  33 17   6.3   3.5
 24000 -30.2 -22.4  190  36 19   7.5   4.1 | -31.4 -24.5  200  29 15   6.3   3.5
 23000 -28.1 -18.6  190  34 18   7.2   4.0 | -29.4 -20.9  200  26 14   7.3   4.0
 22000 -25.9 -14.6  190  33 17   7.2   4.0 | -27.2 -17.0  200  24 13   7.4   4.0
 21000 -23.8 -10.8  190  32 17   7.2   4.0 | -25.0 -13.0  200  23 12   7.4   4.1
 20000 -21.5  -6.7  195  31 16   7.8   4.3 | -22.9  -9.2  205  20 10   6.9   3.8
 19500 -20.3  -4.5  195  30 15   7.8   4.3 | -21.9  -7.4  205  19 10   7.0   3.8
 19000 -19.1  -2.4  195  29 15   7.8   4.3 | -20.8  -5.4  205  18  9   7.0   3.8
 18500 -18.0  -0.4  195  28 15   7.8   4.3 | -19.8  -3.6  205  17  9   6.9   3.8
 18000 -16.3   2.7  200  27 14   7.7   4.2 | -18.2  -0.8  205  16  8   7.4   4.1
 17500 -15.1   4.8  200  26 13   7.7   4.2 | -17.1   1.2  205  15  8   7.4   4.1
 17000 -14.0   6.8  200  24 12   7.1   3.9 | -16.0   3.2  200  14  7   7.6   4.2
 16500 -12.9   8.8  200  22 11   7.2   3.9 | -14.9   5.2  200  14  7   7.6   4.2
 16000 -11.9  10.6  200  20 10   7.4   4.1 | -13.7   7.3  200  14  7   7.6   4.2
 15500 -10.8  12.6  200  18  9   7.6   4.2 | -12.6   9.3  195  14  7   7.7   4.2
 15000  -9.6  14.7  200  16  8   7.4   4.1 | -11.5  11.3  195  14  7   7.8   4.3
 14500  -8.6  16.5  200  14  7   7.0   3.8 | -10.3  13.5  190  14  7   8.3   4.6
 14000  -7.6  18.3  195  13  7   7.1   3.9 |  -9.1  15.6  190  14  7   8.3   4.5
 13500  -6.5  20.3  190  13  7   7.6   4.2 |  -7.8  18.0  190  14  7   8.7   4.8
 13000  -5.4  22.3  185  12  6   7.5   4.1 |  -6.6  20.1  190  14  7   8.6   4.7
 12500  -4.3  24.3  185  12  6   8.4   4.6 |  -5.3  22.5  190  13  7   9.0   5.0
 12000  -3.1  26.4  180  11  6   8.2   4.5 |  -3.9  25.0  195  13  7   9.0   5.0
 11500  -1.8  28.8  175  11  6   9.0   5.0 |  -2.6  27.3  195  12  6   8.8   4.8
 11000  -0.5  31.1  175  11  5   9.1   5.0 |  -1.3  29.7  195  12  6   8.9   4.9
 10500   0.8  33.4  175  10  5   7.9   4.3 |  -0.1  31.8  195  12  6   7.7   4.2
 10250   1.4  34.5  175  10  5   9.0   5.4 |   0.5  32.9  195  12  6   8.8   4.8
 10000   2.2  36.0  175  10  5  10.7   5.9 |   1.3  34.3  195  12  6  10.8   5.9
  9750   3.0  37.4  175  10  5  10.7   5.9 |   2.1  35.8  195  12  6  10.6   5.8
  9500   3.8  38.8  175  10  5  10.5   5.8 |   2.8  37.0  195  12  6   9.8   5.4
  9250   4.6  40.3  175   9  5  10.9   6.0 |   3.6  38.5  200  12  6  10.2   5.6
  9000   5.3  41.5  175   9  5   8.2   4.5 |   4.3  39.7  200  12  6   8.5   4.7
  8750   5.9  42.6  175   9  5   7.9   4.3 |   4.9  40.8  200  12  6   8.2   4.5
  8500   6.6  43.9  175   9  5  10.0   5.5 |   5.5  41.9  200  12  6   9.6   5.3
  8250   7.3  45.1  175   9  5   9.2   5.0 |   6.2  43.2  200  11  6   8.9   4.9
  8000   8.0  46.4  175   9  4  10.2   5.6 |   6.9  44.4  205  11  6  10.1   5.5
  7750   8.8  47.8  175   9  5  10.4   5.7 |   7.7  45.9  200  11  6  10.4   5.7
  7500   9.5  49.1  175   9  5   9.5   5.2 |   8.4  47.1  200  11  6   9.4   5.2
  7250  10.2  50.4  175   9  4  10.0   5.5 |   9.2  48.6  200  11  6  10.2   5.6
  7000  11.0  51.8  175   9  4   8.8   4.8 |   9.9  49.8  200  11  6   8.0   4.4
  6750  11.6  52.9  175   8  4   9.5   5.2 |  10.4  50.7  205  11  6   8.4   4.6
  6500  12.4  54.3  175   8  4  11.0   6.0 |  11.2  52.2  205  10  5  10.9   6.0
  6250  13.2  55.8  175   8  4  10.7   5.9 |  12.0  53.6  205  10  5  10.2   5.6
  6000  14.0  57.2  175   8  4  10.3   5.7 |  12.7  54.9  205   9  5   9.4   5.1
  5750  14.8  58.6  175   7  4  13.7   7.5 |  13.3  55.9  205   9  4   6.9   3.8
  5500  16.1  61.0  175   6  3  20.8  11.4 |  13.7  56.7  205   7  3   4.9   2.7
________________________________________________________________________________

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.

CINH (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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