Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230040
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1840 MDT Friday, May 22, 2015

This forecast is for Saturday, May 23, 2015:

If the trigger temperature of 62.7 F/17.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 39 ft/min (0.2 m/s)
   Maximum height of thermals.................. 11355 ft MSL (6048 ft AGL)

Forecast maximum temperature................... 68.0 F/20.5 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 9225 ft MSL (3919 ft AGL)
Thermal soaring outlook for Sunday 05/24....... Excellent

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....................... 16614 ft MSL (11307 ft AGL)
Wave soaring outlook for Sunday 05/24.......... Poor

Remarks... Increasing southerly flow through the day. Airmass becoming unstable
           with strong thunderstorms possible.

Sunrise/Sunset.................... 05:38:44 / 20:13:32 MDT
Total possible sunshine........... 14 hr 34 min 49 sec (874 min 49 sec)
Altitude of sun at 12:56:20 MDT... 70.84 degrees

Upper air data from numerical model forecast valid on 05/23/2015 at 0600 MDT

Freezing level.................. 12114 ft MSL (6807 ft AGL)
Convective condensation level... 11603 ft MSL (6296 ft AGL)
Lifted condensation level....... 11632 ft MSL (6325 ft AGL)
Lifted index.................... -4.8
K index......................... +15.3

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  -57.3 -71.1   245   27   14   1.8   1.0      M     M       M      M    M
 45000  -54.9 -66.8   230   46   23  -1.5  -0.8      M     M       M      M    M
 40000  -57.1 -70.8   210   86   44  -1.4  -0.8      M     M       M      M    M
 38000  -55.3 -67.5   205   94   48   5.1   2.8      M     M       M      M    M
 36000  -52.2 -62.0   205   98   50   5.1   2.8      M     M       M      M    M
 34000  -48.8 -55.8   205   99   51   7.3   4.0      M     M       M      M    M
 32000  -44.3 -47.7   205   93   48   7.4   4.0      M     M       M      M    M
 30000  -39.9 -39.8   210   84   43   5.1   2.8   36.1  97.0    12.2      M    M
 29000  -38.4 -37.1   210   77   40   5.1   2.8   34.2  93.6    10.9      M    M
 28000  -36.8 -34.2   215   71   36   5.1   2.8   32.5  90.5     9.7      M    M
 27000  -35.1 -31.2   215   64   33   7.6   4.2   31.0  87.9     8.6      M    M
 26000  -32.9 -27.2   215   58   30   7.4   4.1   30.0  86.1     7.9      M    M
 25000  -30.7 -23.3   210   52   27   7.4   4.1   29.2  84.5     7.3      M    M
 24000  -28.5 -19.3   210   47   24   7.4   4.1   28.4  83.1     6.7      M    M
 23000  -26.3 -15.3   210   44   22   7.4   4.0   27.4  81.4     6.0      M    M
 22000  -24.1 -11.4   205   40   21   7.4   4.0   26.6  79.9     5.4      M    M
 21000  -21.8  -7.2   205   37   19   8.8   4.8   25.9  78.6     4.9      M    M
 20000  -19.2  -2.6   210   36   19   8.7   4.8   25.5  77.8     4.6      M    M
 19500  -17.9  -0.2   210   36   18   8.7   4.8   25.3  77.5     4.4      M    M
 19000  -16.6   2.1   210   35   18   8.7   4.8   25.1  77.2     4.3      M    M
 18500  -15.3   4.5   210   35   18   8.3   4.6   25.0  76.9     4.2      M    M
 18000  -14.1   6.6   210   34   18   8.3   4.5   24.7  76.5     4.0      M    M
 17500  -12.9   8.8   210   33   17   8.2   4.5   24.5  76.0     3.8      M    M
 17000  -11.7  10.9   215   34   18   7.9   4.4   24.1  75.5     3.5      M    M
 16500  -10.5  13.1   215   35   18   8.0   4.4   23.8  74.9     3.3      M    M
 16000   -9.3  15.3   220   36   18   7.4   4.1   23.5  74.3     3.0      M    M
 15500   -7.7  18.1   220   35   18   7.5   4.1   22.9  73.3     2.5      M    M
 15000   -6.6  20.1   220   35   18   8.0   4.4   22.6  72.7     2.1      M    M
 14500   -5.4  22.3   220   34   18   8.0   4.4   22.3  72.2     1.9      M    M
 14000   -4.2  24.4   225   33   17   8.3   4.6   22.1  71.7     1.6      M    M
 13500   -3.0  26.6   225   30   15   8.4   4.6   21.8  71.3     1.4      M    M
 13000   -1.8  28.8   225   27   14   7.6   4.1   21.6  70.8     1.1      M    M
 12500   -0.7  30.7   225   24   12   7.4   4.1   21.2  70.1     0.7      M    M
 12000    0.4  32.7   230   20   10   7.9   4.4   20.8  69.5     0.4      M    M
 11500    1.5  34.7   230   17    9   8.2   4.5   20.6  69.0     0.1      M    M
 11000    2.7  36.9   230   15    8   7.6   4.2   20.3  68.5    -0.3    400  2.0
 10500    3.7  38.7   225   13    7   8.0   4.4   19.9  67.8    -0.7    355  1.8
 10250    4.2  39.6   225   12    6   5.0   2.7   19.7  67.5    -0.9    332  1.7
 10000    4.4  39.9   225   11    6   2.8   1.5   19.2  66.5    -1.5    319  1.6
  9750    4.6  40.3   225   10    5   4.1   2.2   18.7  65.7    -2.0    304  1.5
  9500    4.9  40.8   225    9    5   4.2   2.3   18.3  64.9    -2.5    290  1.5
  9250    5.1  41.2   225    8    4   2.7   1.5   17.8  64.0    -3.0    275  1.4
  9000    5.1  41.2   230    7    3  -0.3  -0.1   17.1  62.8    -3.7    267  1.4
  8750    5.1  41.2   230    6    3  -0.3  -0.2   16.3  61.4    -4.5    262  1.3
  8500    5.0  41.0   235    5    3  -0.1  -0.1   15.6  60.0    -5.3    256  1.3
  8250    5.0  41.0   240    5    2   0.7   0.4   14.8  58.7    -6.0    249  1.3
  8000    5.1  41.2   235    5    2   2.0   1.1   14.2  57.5    -6.7    240  1.2
  7750    5.2  41.4   235    5    2   2.5   1.4   13.6  56.5    -7.3    229  1.2
  7500    5.4  41.7   235    5    2   3.0   1.6   13.1  55.5    -7.9    216  1.1
  7250    5.6  42.1   230    4    2   4.1   2.3   12.6  54.6    -8.4    202  1.0
  7000    5.9  42.6   225    4    2   5.2   2.8   12.2  54.0    -8.9    185  0.9
  6750    6.2  43.2   215    4    2   4.1   2.3   11.8  53.3    -9.3    168  0.9
  6500    6.5  43.7   205    4    2   5.8   3.2   11.4  52.6    -9.7    152  0.8
  6250    7.0  44.6   195    4    2   8.3   4.6   11.2  52.2   -10.0    129  0.7
  6000    7.6  45.7   180    3    2   8.5   4.7   11.1  52.1   -10.1    104  0.5
  5750    8.2  46.8   165    3    1   7.7   4.3   11.0  51.9   -10.3     79  0.4
  5500    8.7  47.7   140    2    1   6.6   3.6   10.8  51.5   -10.6     57  0.3

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

           05/23/2015 at 0900 MDT          |       05/23/2015 at 1200 MDT
                                           |
K index... +20.3  LI... +271.5             | K index... +14.9  LI... +268.0
CAPE... +190.8  CIN... -120.2              | CAPE... +963.0  CIN... -22.2
                                           |
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 -56.7 -70.1  235  19 10   2.6   1.4 | -56.2 -69.2  220  12  6   2.9   1.6
 45000 -53.1 -63.6  220  38 20  -2.1  -1.2 | -52.2 -62.0  215  27 14  -1.4  -0.8
 40000 -56.1 -69.0  200  81 41  -2.0  -1.1 | -54.1 -65.4  195  71 37  -1.3  -0.7
 38000 -54.8 -66.6  200  90 46   4.5   2.5 | -53.2 -63.8  195  83 43   3.3   1.8
 36000 -52.1 -61.8  195  95 49   4.5   2.5 | -51.2 -60.2  195  92 47   3.3   1.8
 34000 -49.0 -56.2  195  97 50   7.0   3.8 | -48.8 -55.8  200  97 50   5.9   3.2
 32000 -44.7 -48.5  200  93 48   7.1   3.9 | -44.9 -48.8  200  88 45   5.9   3.2
 30000 -40.1 -40.2  200  86 44   6.2   3.4 | -41.2 -42.2  200  79 41   6.8   3.7
 29000 -38.3 -36.9  200  79 41   6.2   3.4 | -39.1 -38.4  200  72 37   6.8   3.7
 28000 -36.4 -33.5  200  73 38   6.2   3.4 | -37.1 -34.8  200  65 34   6.8   3.7
 27000 -34.6 -30.3  200  67 34   6.5   3.6 | -35.0 -31.0  200  59 30   6.9   3.8
 26000 -32.6 -26.7  200  62 32   6.5   3.6 | -33.0 -27.4  195  57 30   6.9   3.8
 25000 -30.7 -23.3  200  57 29   6.6   3.6 | -30.9 -23.6  195  56 29   6.9   3.8
 24000 -28.8 -19.8  200  52 27   6.8   3.7 | -28.8 -19.8  190  54 28   7.0   3.9
 23000 -26.7 -16.1  200  50 26   6.9   3.8 | -26.7 -16.1  190  50 26   7.1   3.9
 22000 -24.6 -12.3  200  47 24   6.9   3.8 | -24.6 -12.3  195  46 24   7.2   3.9
 21000 -22.5  -8.5  205  44 23   8.2   4.5 | -22.4  -8.3  195  42 21   7.9   4.3
 20000 -20.0  -4.0  205  39 20   8.2   4.5 | -20.0  -4.0  195  37 19   7.9   4.3
 19500 -18.8  -1.8  205  37 19   8.2   4.5 | -18.8  -1.8  195  35 18   7.9   4.3
 19000 -17.5   0.5  205  34 18   8.2   4.5 | -17.6   0.3  195  33 17   7.9   4.4
 18500 -16.3   2.7  210  32 16   7.4   4.1 | -16.5   2.3  195  31 16   7.1   3.9
 18000 -15.3   4.5  210  30 15   7.2   4.0 | -15.5   4.1  190  28 15   6.8   3.7
 17500 -14.2   6.4  210  27 14   7.3   4.0 | -14.5   5.9  190  26 13   6.8   3.7
 17000 -13.1   8.4  205  25 13   7.7   4.2 | -13.4   7.9  190  24 12   7.6   4.2
 16500 -11.9  10.6  205  24 12   7.7   4.2 | -11.7  10.9  185  21 11   7.8   4.3
 16000 -10.3  13.5  205  22 11   7.8   4.3 | -10.5  13.1  180  19 10   8.6   4.7
 15500  -9.1  15.6  205  22 11   7.9   4.3 |  -9.2  15.4  175  17  9   8.6   4.7
 15000  -7.9  17.8  205  21 11   9.6   5.3 |  -7.9  17.8  170  17  9   9.7   5.3
 14500  -6.5  20.3  200  21 11   9.5   5.2 |  -6.5  20.3  170  17  9   9.7   5.3
 14000  -5.1  22.8  200  21 11   9.6   5.2 |  -5.1  22.8  170  17  9   9.3   5.1
 13500  -3.7  25.3  195  20 10   9.6   5.3 |  -3.8  25.2  170  17  9   9.3   5.1
 13000  -2.3  27.9  190  19 10   8.9   4.9 |  -2.4  27.7  175  18  9   9.0   4.9
 12500  -1.0  30.2  185  17  9   8.7   4.8 |  -1.1  30.0  175  19 10   8.9   4.9
 12000   0.2  32.4  180  16  8   7.7   4.2 |   0.2  32.4  180  20 10   9.0   4.9
 11500   1.2  34.2  180  15  7   7.2   4.0 |   1.5  34.7  180  20 10   9.1   5.0
 11000   2.3  36.1  175  13  7   7.0   3.8 |   2.9  37.2  180  20 10   7.9   4.3
 10500   3.3  37.9  175  12  6   6.3   3.5 |   3.9  39.0  180  20 10   6.6   3.6
 10250   3.7  38.7  175  12  6   9.6   5.3 |   4.4  39.9  180  20 10  10.0   5.5
 10000   4.5  40.1  170  11  6   9.2   5.0 |   5.2  41.4  185  19 10   9.9   5.4
  9750   5.0  41.0  165  11  6   5.6   3.1 |   5.7  42.3  185  19 10   6.4   3.5
  9500   5.4  41.7  165  11  6   6.6   3.6 |   6.2  43.2  185  18  9   7.3   4.0
  9250   5.8  42.4  165  11  6   6.1   3.3 |   6.7  44.1  185  17  9   7.2   4.0
  9000   6.2  43.2  160  11  5   4.2   2.3 |   7.2  45.0  185  16  8   4.8   2.7
  8750   6.4  43.5  165  11  5   2.5   1.4 |   7.3  45.1  180  14  7   2.9   1.6
  8500   6.6  43.9  165  10  5   3.6   2.0 |   7.5  45.5  175  12  6   3.5   1.9
  8250   6.8  44.2  165  10  5   0.2   0.1 |   7.7  45.9  170  10  5   3.5   1.9
  8000   6.5  43.7  170  10  5  -3.6  -2.0 |   7.9  46.2  155   7  4   4.7   2.6
  7750   6.3  43.3  175  10  5  -1.5  -0.8 |   8.2  46.8  145   6  3   6.4   3.5
  7500   6.2  43.2  185  10  5  -0.5  -0.3 |   8.6  47.5  135   5  3   6.4   3.5
  7250   6.2  43.2  190  10  5   2.6   1.4 |   9.0  48.2  125   5  2   8.6   4.7
  7000   6.5  43.7  195   9  5   5.2   2.8 |   9.8  49.6  125   5  2  10.8   5.9
  6750   6.8  44.2  200   8  4   5.5   3.0 |  10.6  51.1  125   5  2   9.9   5.4
  6500   7.3  45.1  205   7  3   8.4   4.6 |  11.3  52.3  125   5  2  10.3   5.7
  6250   8.0  46.4  205   6  3  10.5   5.8 |  12.1  53.8  120   4  2  11.1   6.1
  6000   8.8  47.8  205   5  3  10.6   5.8 |  13.0  55.4  120   4  2  11.7   6.4
  5750   9.5  49.1  205   5  3  10.9   6.0 |  13.8  56.8  120   4  2  10.3   5.6
  5500  10.5  50.9  205   5  2  15.5   8.5 |  14.6  58.3  120   4  2  15.2   8.3

           05/23/2015 at 1500 MDT          |       05/23/2015 at 1800 MDT
                                           |
K index... +31.4  LI... +268.1             | K index... +23.7  LI... +269.4
CAPE... +1010.1  CIN... -1.2               | CAPE... +483.4  CIN... -6.5
                                           |
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 -57.0 -70.6  200  11  6   2.2   1.2 | -57.4 -71.3  200  11  6   1.5   0.8
 45000 -53.7 -64.7  200  19 10   0.1   0.1 | -55.0 -67.0  190  21 11   1.2   0.6
 40000 -53.5 -64.3  195  63 32   0.1   0.1 | -53.3 -63.9  190  50 26   1.1   0.6
 38000 -52.3 -62.1  195  73 38   3.2   1.7 | -51.7 -61.1  190  57 29   3.5   1.9
 36000 -50.4 -58.7  195  79 41   3.2   1.7 | -49.6 -57.3  195  62 32   3.5   1.9
 34000 -48.3 -54.9  195  82 42   5.0   2.7 | -47.2 -53.0  195  63 33   5.1   2.8
 32000 -44.9 -48.8  200  71 37   5.0   2.7 | -43.8 -46.8  200  54 28   5.1   2.8
 30000 -41.5 -42.7  205  62 32   7.3   4.0 | -40.5 -40.9  200  45 23   6.2   3.4
 29000 -39.3 -38.7  205  58 30   7.3   4.0 | -38.6 -37.5  200  39 20   6.3   3.4
 28000 -37.1 -34.8  205  55 28   7.3   4.0 | -36.7 -34.1  205  33 17   6.3   3.4
 27000 -35.0 -31.0  205  50 26   7.5   4.1 | -34.8 -30.6  205  28 14   6.8   3.7
 26000 -32.7 -26.9  205  45 23   7.5   4.1 | -32.8 -27.0  200  24 12   6.9   3.8
 25000 -30.5 -22.9  205  40 21   7.5   4.1 | -30.7 -23.3  195  20 10   6.9   3.8
 24000 -28.2 -18.8  200  35 18   7.7   4.2 | -28.6 -19.5  185  17  9   7.2   4.0
 23000 -25.9 -14.6  200  33 17   7.8   4.3 | -26.3 -15.3  180  18  9   7.7   4.2
 22000 -23.6 -10.5  200  31 16   7.9   4.3 | -24.0 -11.2  180  20 10   7.7   4.2
 21000 -21.3  -6.3  200  28 14   7.3   4.0 | -21.8  -7.2  175  21 11   7.0   3.9
 20000 -19.1  -2.4  200  25 13   7.2   4.0 | -19.7  -3.5  185  22 11   6.9   3.8
 19500 -18.1  -0.6  200  23 12   7.2   4.0 | -18.7  -1.7  185  23 12   6.9   3.8
 19000 -17.0   1.4  195  21 11   7.3   4.0 | -17.7   0.1  190  24 12   6.9   3.8
 18500 -15.9   3.4  195  20 10   7.3   4.0 | -16.7   1.9  190  24 13   7.5   4.1
 18000 -14.9   5.2  190  20 10   7.3   4.0 | -15.5   4.1  195  25 13   8.0   4.4
 17500 -13.8   7.2  185  21 11   7.4   4.0 | -14.3   6.3  200  26 13   8.1   4.4
 17000 -12.7   9.1  180  21 11   7.1   3.9 | -13.1   8.4  205  26 14   8.5   4.6
 16500 -11.2  11.8  175  22 11   7.2   3.9 | -11.2  11.8  210  27 14   8.5   4.6
 16000 -10.1  13.8  175  23 12   7.5   4.1 | -10.0  14.0  210  26 13   8.6   4.7
 15500  -9.0  15.8  175  24 12   7.5   4.1 |  -8.7  16.3  210  25 13   8.6   4.7
 15000  -7.9  17.8  175  24 13   8.3   4.5 |  -7.5  18.5  210  25 13   8.5   4.6
 14500  -6.7  19.9  170  24 12   8.3   4.5 |  -6.2  20.8  210  24 12   8.5   4.6
 14000  -5.5  22.1  170  24 12   7.9   4.3 |  -5.0  23.0  210  23 12   8.6   4.7
 13500  -4.4  24.1  170  23 12   7.8   4.3 |  -3.7  25.3  205  21 11   8.6   4.7
 13000  -3.3  26.1  170  22 11   7.7   4.2 |  -2.5  27.5  205  20 10   8.4   4.6
 12500  -2.2  28.0  165  20 10   7.7   4.2 |  -1.3  29.7  200  18  9   8.4   4.6
 12000  -1.1  30.0  165  18  9   8.5   4.6 |  -0.1  31.8  195  17  9   8.9   4.9
 11500   0.2  32.4  160  17  9   9.2   5.1 |   1.2  34.2  200  16  8   9.5   5.2
 11000   1.5  34.7  160  15  8   9.0   5.0 |   2.6  36.7  200  15  8   9.1   5.0
 10500   2.8  37.0  160  14  7   8.0   4.4 |   3.9  39.0  200  14  7   7.8   4.3
 10250   3.5  38.3  155  13  7  11.9   6.5 |   4.5  40.1  200  14  7  10.8   5.9
 10000   4.5  40.1  155  13  7  12.9   7.1 |   5.4  41.7  200  13  7  11.8   6.5
  9750   5.2  41.4  155  13  6   9.8   5.4 |   6.2  43.2  205  13  6   9.3   5.1
  9500   6.0  42.8  155  12  6  10.6   5.8 |   6.9  44.4  205  12  6   9.9   5.4
  9250   6.8  44.2  155  12  6  10.4   5.7 |   7.6  45.7  205  11  6   9.2   5.0
  9000   7.5  45.5  155  11  6   9.9   5.5 |   8.3  46.9  210  11  5   9.1   5.0
  8750   8.3  46.9  155  11  6   9.6   5.3 |   9.0  48.2  210  10  5   9.7   5.3
  8500   9.0  48.2  155  11  6   9.4   5.2 |   9.7  49.5  210   9  5   9.3   5.1
  8250   9.7  49.5  155  11  6  10.7   5.9 |  10.4  50.7  210   9  4  10.4   5.7
  8000  10.6  51.1  155  10  5  11.5   6.3 |  11.2  52.2  215   8  4  11.2   6.1
  7750  11.3  52.3  155  10  5   9.9   5.4 |  12.0  53.6  220   7  4   9.5   5.2
  7500  12.0  53.6  150  10  5   9.1   5.0 |  12.6  54.7  220   7  4   8.6   4.7
  7250  12.7  54.9  150  10  5  10.2   5.6 |  13.3  55.9  225   7  3   9.6   5.3
  7000  13.6  56.5  150   9  5  11.2   6.2 |  14.0  57.2  225   6  3  10.7   5.9
  6750  14.3  57.7  150   9  5  10.0   5.5 |  14.8  58.6  230   6  3   9.8   5.4
  6500  15.1  59.2  150   9  5   9.4   5.2 |  15.5  59.9  230   6  3   9.1   5.0
  6250  15.8  60.4  150   9  4  10.7   5.9 |  16.2  61.2  235   6  3  10.1   5.5
  6000  16.6  61.9  150   8  4  11.9   6.5 |  17.0  62.6  240   5  3  11.0   6.0
  5750  17.5  63.5  150   8  4   9.9   5.4 |  17.7  63.9  240   5  3   9.8   5.4
  5500  18.2  64.8  150   7  3  12.6   6.9 |  18.4  65.1  250   4  2  10.2   5.6
________________________________________________________________________________

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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