Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231216
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0616 MDT Thursday, October 23, 2014

This forecast is for Thursday, October 23, 2014:

If the trigger temperature of 64.9 F/18.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 872 ft/min (4.4 m/s)
   Maximum height of thermals.................. 15967 ft MSL (10682 ft AGL)

Forecast maximum temperature................... 78.0 F/26.0 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 13237 ft MSL (7952 ft AGL)
Thermal soaring outlook for Friday 10/24....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... 10
Height of stable layer (12-18K ft MSL)......... 17124 ft MSL (11839 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 35621 ft MSL (30336 ft AGL)
Wave soaring outlook for Friday 10/24.......... Good

Remarks...

Sunrise/Sunset.................... 07:18:21 / 18:10:11 MDT
Total possible sunshine........... 10 hr 51 min 50 sec (651 min 50 sec)
Altitude of sun at 12:43:52 MDT... 38.69 degrees

Upper air data from rawinsonde observation taken on 10/23/2014 at 0600 MDT

Freezing level.................. 12325 ft MSL (7040 ft AGL)
Convective condensation level... 15917 ft MSL (10632 ft AGL)
Lifted condensation level....... 16138 ft MSL (10853 ft AGL)
Lifted index.................... +2.0
K index......................... +4.1

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  -62.9 -81.2   280   52   27   5.3   2.9   91.9 197.5    38.2      M    M
 45000  -58.3 -72.9   295   58   30 -10.5  -5.7   75.1 167.1    30.5      M    M
 40000  -61.4 -78.5   330   80   41   0.9   0.5   47.1 116.7    14.2      M    M
 38000  -58.5 -73.3   325   77   39   7.3   4.0   42.6 108.8    11.6      M    M
 36000  -53.5 -64.3   320   66   34   8.7   4.8   41.4 106.6    11.1      M    M
 34000  -47.3 -53.1   310   63   33   8.0   4.4   40.9 105.6    11.0      M    M
 32000  -42.2 -44.0   305   58   30   9.2   5.0   39.8 103.7    10.5      M    M
 30000  -36.7 -34.1   305   52   27   9.1   5.0   39.3 102.8    10.4      M    M
 29000  -34.1 -29.4   300   52   27   7.7   4.2   38.9 102.0    10.2      M    M
 28000  -31.7 -25.1   300   52   27   8.1   4.4   38.2 100.8     9.8      M    M
 27000  -29.3 -20.7   295   52   27   8.2   4.5   37.7  99.8     9.5      M    M
 26000  -26.8 -16.2   300   48   25   8.2   4.5   37.0  98.6     9.1      M    M
 25000  -24.3 -11.7   305   44   23   8.1   4.4   36.5  97.7     8.8      M    M
 24000  -21.8  -7.2   315   41   21   8.1   4.5   36.0  96.8     8.5      M    M
 23000  -19.3  -2.7   320   41   21   8.2   4.5   35.5  95.8     8.1      M    M
 22000  -16.9   1.6   315   37   19   8.3   4.6   34.9  94.8     7.7      M    M
 21000  -14.7   5.5   305   34   18   7.0   3.8   34.0  93.1     7.0      M    M
 20000  -12.9   8.8   295   32   17   3.8   2.1   32.8  91.0     6.0      M    M
 19500  -12.3   9.9   295   31   16   4.2   2.3   31.8  89.2     5.2      M    M
 19000  -11.5  11.3   300   30   16   5.8   3.2   31.0  87.8     4.5      M    M
 18500  -10.8  12.6   300   28   14   4.7   2.6   30.1  86.2     3.8      M    M
 18000  -10.1  13.8   305   25   13   4.8   2.6   29.2  84.6     3.0      M    M
 17500   -9.4  15.1   305   22   11   5.2   2.8   28.4  83.1     2.3      M    M
 17000   -9.1  15.6   315   18    9   3.4   1.9   26.2  79.2     0.4      M    M
 16500   -7.9  17.8   320   16    8   7.9   4.4   26.0  78.8     0.2      M    M
 16000   -6.6  20.1   325   14    7   8.2   4.5   25.7  78.3    -0.0    864  4.4
 15500   -5.4  22.3   320   15    8   7.1   3.9   25.5  77.9    -0.3    812  4.1
 15000   -4.5  23.9   315   16    8   5.7   3.1   24.8  76.7    -0.9    771  3.9
 14500   -3.7  25.3   310   17    9   5.6   3.1   24.1  75.4    -1.5    731  3.7
 14000   -2.8  27.0   305   18    9   5.6   3.1   23.5  74.2    -2.1    691  3.5
 13500   -2.0  28.4   310   18    9   5.8   3.2   22.8  73.0    -2.8    651  3.3
 13000   -1.1  30.0   310   17    9   6.1   3.4   22.2  71.9    -3.4    610  3.1
 12500   -0.2  31.6   315   17    9   6.2   3.4   21.6  70.8    -4.0    568  2.9
 12000    0.7  33.3   315   17    9   7.8   4.3   21.1  69.9    -4.5    526  2.7
 11500    2.0  35.6   315   14    7   9.0   4.9   20.9  69.6    -4.7    472  2.4
 11000    2.9  37.2   320   11    6   3.8   2.1   20.3  68.6    -5.3    431  2.2
 10500    3.4  38.1   300   12    6   5.7   3.1   19.5  67.0    -6.3    400  2.0
 10250    3.9  39.0   295   13    7   8.3   4.6   19.3  66.7    -6.6    377  1.9
 10000    4.6  40.3   295   15    8   8.5   4.7   19.2  66.5    -6.7    351  1.8
  9750    5.2  41.4   295   16    8   8.5   4.6   19.1  66.3    -6.8    325  1.7
  9500    5.8  42.4   290   17    9   8.5   4.7   19.0  66.2    -6.9    299  1.5
  9250    6.4  43.5   290   17    9   8.5   4.7   18.9  66.0    -7.0    273  1.4
  9000    7.1  44.8   290   18    9   8.5   4.7   18.8  65.9    -7.1    247  1.3
  8750    7.7  45.9   290   17    9   8.5   4.7   18.7  65.7    -7.3    221  1.1
  8500    8.3  46.9   290   16    8   8.5   4.7   18.6  65.5    -7.4    194  1.0
  8250    8.9  48.0   285   16    8   8.5   4.7   18.5  65.3    -7.5    168  0.9
  8000    9.6  49.3   285   15    8   8.5   4.7   18.4  65.2    -7.6    142  0.7
  7750   10.2  50.4   285   14    7   8.5   4.6   18.3  65.0    -7.8    116  0.6
  7500   10.8  51.4   285   13    6   8.6   4.7   18.2  64.8    -7.9     90  0.5
  7250   11.4  52.5   280   11    6   8.1   4.4   18.1  64.6    -8.0     64  0.3
  7000   12.1  53.8   280   10    5  10.0   5.5   18.0  64.4    -8.2     37  0.2
  6750   12.7  54.9   275    8    4   2.9   1.6   17.9  64.2    -8.3     11  0.1
  6500   12.4  54.3   260    7    3  -6.2  -3.4   16.9  62.4    -9.4     13  0.1
  6250   11.9  53.4   240    5    3  -6.1  -3.3   15.7  60.3   -10.6     20  0.1
  6000   11.4  52.5   220    5    3  -5.0  -2.7   14.5  58.1   -11.8     27  0.1
  5750   10.9  51.6   210    5    2  -9.4  -5.2   13.3  56.0   -13.1     34  0.2
  5500    9.5  49.1   205    4    2 -32.0 -17.6   11.2  52.1   -15.3     71  0.4

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

           10/23/2014 at 0900 MDT          |       10/23/2014 at 1200 MDT
                                           |
K index... +12.6  LI... +4.9               | K index... +10.7  LI... +5.3
CAPE... 0.0  CIN... -0.8                   | 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 -64.7 -84.5  285  47 24   2.0   1.1 | -65.9 -86.6  290  47 24   0.4   0.2
 45000 -61.8 -79.2  295  73 38   1.7   0.9 | -64.7 -84.5  300  66 34   3.0   1.7
 40000 -59.2 -74.6  320  79 41   2.2   1.2 | -60.2 -76.4  315  80 41   4.3   2.3
 38000 -55.1 -67.2  325  75 38   7.3   4.0 | -55.6 -68.1  315  73 38   7.8   4.3
 36000 -50.7 -59.3  325  70 36   7.3   4.0 | -51.0 -59.8  315  66 34   7.8   4.3
 34000 -45.8 -50.4  325  61 31   7.1   3.9 | -45.6 -50.1  315  58 30   8.1   4.4
 32000 -41.5 -42.7  320  51 26   7.1   3.9 | -40.7 -41.3  315  51 26   8.1   4.4
 30000 -36.8 -34.2  315  48 25   8.2   4.5 | -35.9 -32.6  310  48 25   8.1   4.5
 29000 -34.3 -29.7  315  48 25   8.2   4.5 | -33.4 -28.1  310  47 24   8.1   4.5
 28000 -31.8 -25.2  315  49 25   8.2   4.5 | -31.0 -23.8  310  46 24   8.1   4.5
 27000 -29.4 -20.9  315  47 24   8.3   4.5 | -28.6 -19.5  310  45 23   8.0   4.4
 26000 -26.9 -16.4  310  45 23   8.3   4.5 | -26.2 -15.2  310  43 22   8.0   4.4
 25000 -24.4 -11.9  310  43 22   8.3   4.5 | -23.8 -10.8  310  41 21   8.0   4.4
 24000 -22.0  -7.6  310  41 21   8.0   4.4 | -21.4  -6.5  310  40 20   8.0   4.4
 23000 -19.5  -3.1  310  39 20   8.0   4.4 | -19.0  -2.2  310  38 20   8.0   4.4
 22000 -17.1   1.2  310  37 19   8.1   4.4 | -16.6   2.1  310  36 19   8.1   4.4
 21000 -15.0   5.0  310  34 18   6.5   3.6 | -14.5   5.9  310  35 18   6.7   3.7
 20000 -13.1   8.4  310  33 17   6.5   3.6 | -12.5   9.5  310  34 17   6.7   3.7
 19500 -12.1  10.2  310  32 16   6.5   3.6 | -11.5  11.3  310  33 17   6.7   3.7
 19000 -11.2  11.8  310  31 16   5.9   3.2 | -10.5  13.1  310  32 17   6.9   3.8
 18500 -10.5  13.1  310  29 15   4.2   2.3 |  -9.5  14.9  315  32 16   7.1   3.9
 18000  -9.9  14.2  305  27 14   4.2   2.3 |  -8.4  16.9  315  31 16   7.2   4.0
 17500  -9.2  15.4  305  25 13   4.7   2.6 |  -7.5  18.5  315  30 16   5.8   3.2
 17000  -8.5  16.7  300  24 12   4.8   2.6 |  -6.6  20.1  315  29 15   5.8   3.2
 16500  -7.5  18.5  300  21 11   5.0   2.7 |  -5.4  22.3  315  27 14   5.6   3.1
 16000  -6.7  19.9  295  20 10   5.0   2.7 |  -4.5  23.9  315  26 13   5.7   3.1
 15500  -6.0  21.2  295  19 10   5.1   2.8 |  -3.7  25.3  310  24 12   4.9   2.7
 15000  -5.3  22.5  290  17  9   5.2   2.8 |  -3.1  26.4  310  22 11   4.7   2.6
 14500  -4.5  23.9  285  15  8   5.8   3.2 |  -2.4  27.7  305  20 10   4.6   2.5
 14000  -3.6  25.5  285  14  7   6.8   3.7 |  -1.7  28.9  305  18  9   4.6   2.5
 13500  -2.6  27.3  285  12  6   6.9   3.8 |  -1.0  30.2  300  16  8   4.9   2.7
 13000  -1.6  29.1  280  11  5   7.2   4.0 |  -0.2  31.6  295  14  7   5.9   3.2
 12500  -0.5  31.1  280   9  5   7.3   4.0 |   0.6  33.1  290  13  6   6.1   3.3
 12000   0.6  33.1  285   9  4   8.3   4.6 |   1.7  35.1  280  11  6   7.5   4.1
 11500   1.9  35.4  290   8  4   8.2   4.5 |   2.7  36.9  275  10  5   7.4   4.1
 11000   3.0  37.4  295   9  5   7.6   4.2 |   3.9  39.0  275  10  5   7.8   4.3
 10500   4.1  39.4  300  10  5   6.7   3.7 |   5.0  41.0  275   9  5   6.5   3.6
 10250   4.6  40.3  300  11  5   4.8   2.7 |   5.4  41.7  275   9  5   5.1   2.8
 10000   5.0  41.0  300  11  6   8.0   4.4 |   5.9  42.6  280   9  5   8.7   4.8
  9750   5.7  42.3  300  12  6  10.8   5.9 |   6.7  44.1  280  10  5  11.2   6.1
  9500   6.4  43.5  305  13  7   9.1   5.0 |   7.5  45.5  285  10  5   9.3   5.1
  9250   7.0  44.6  300  14  7   6.7   3.7 |   8.0  46.4  285  10  5   6.6   3.6
  9000   7.5  45.5  300  14  7   7.2   4.0 |   8.5  47.3  290  11  6   6.7   3.7
  8750   8.1  46.6  300  14  7   8.9   4.9 |   9.0  48.2  290  11  6   8.0   4.4
  8500   8.7  47.7  300  14  7   7.9   4.3 |   9.6  49.3  290  11  6   6.9   3.8
  8250   9.3  48.7  300  13  7   7.0   3.8 |  10.0  50.0  285  10  5   5.9   3.3
  8000   9.8  49.6  295  12  6   7.2   4.0 |  10.5  50.9  280   8  4   6.3   3.4
  7750  10.4  50.7  295  11  6   7.3   4.0 |  10.9  51.6  265   7  4   6.8   3.7
  7500  10.9  51.6  290  10  5   6.4   3.5 |  11.5  52.7  250   6  3   7.8   4.3
  7250  11.3  52.3  285   9  5   5.6   3.1 |  12.1  53.8  240   6  3   8.4   4.6
  7000  11.8  53.2  280   8  4   6.3   3.4 |  12.7  54.9  225   5  3   8.3   4.6
  6750  12.2  54.0  275   7  3   5.1   2.8 |  13.3  55.9  210   6  3   9.4   5.1
  6500  12.5  54.5  260   6  3   2.2   1.2 |  14.1  57.4  205   6  3  10.2   5.6
  6250  12.7  54.9  250   5  3   4.1   2.2 |  14.8  58.6  205   5  3   9.8   5.4
  6000  12.9  55.2  235   5  3  -3.9  -2.1 |  15.6  60.1  205   5  3  10.8   5.9
  5750  12.0  53.6  225   6  3 -14.6  -8.0 |  16.5  61.7  205   5  3  14.3   7.9
  5500  11.0  51.8  210   5  3  -7.9  -4.3 |  17.7  63.9  205   5  2  17.3   9.5

           10/23/2014 at 1500 MDT          |       10/23/2014 at 1800 MDT
                                           |
K index... +6.5  LI... +3.5                | K index... +11.3  LI... +2.3
CAPE... 0.0  CIN... -0.5                   | 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 -66.9 -88.4  300  49 25   0.2   0.1 | -66.6 -87.9  300  43 22  -0.5  -0.3
 45000 -65.9 -86.6  305  65 33   3.3   1.8 | -66.2 -87.2  305  61 32   4.0   2.2
 40000 -60.9 -77.6  315  72 37   5.5   3.0 | -60.2 -76.4  315  76 39   6.4   3.5
 38000 -55.9 -68.6  315  67 34   8.4   4.6 | -55.2 -67.4  315  70 36   8.3   4.6
 36000 -50.9 -59.6  315  62 32   8.4   4.6 | -50.2 -58.4  315  64 33   8.3   4.6
 34000 -45.8 -50.4  310  55 28   8.6   4.7 | -44.5 -48.1  315  56 29   8.6   4.7
 32000 -39.9 -39.8  305  47 24   8.7   4.7 | -39.3 -38.7  310  48 25   8.6   4.7
 30000 -34.8 -30.6  305  46 23   8.5   4.7 | -34.3 -29.7  310  46 24   8.5   4.7
 29000 -32.3 -26.1  305  46 24   8.5   4.7 | -31.7 -25.1  305  47 24   8.5   4.7
 28000 -29.7 -21.5  305  46 24   8.5   4.7 | -29.2 -20.6  305  47 24   8.4   4.6
 27000 -27.3 -17.1  305  45 23   7.9   4.3 | -26.9 -16.4  305  47 24   7.3   4.0
 26000 -25.0 -13.0  305  44 23   7.9   4.4 | -24.8 -12.6  305  47 24   7.3   4.0
 25000 -22.6  -8.7  300  43 22   8.0   4.4 | -22.6  -8.7  305  47 24   7.4   4.1
 24000 -20.5  -4.9  305  42 21   6.4   3.5 | -20.6  -5.1  305  45 23   6.5   3.6
 23000 -18.6  -1.5  305  40 21   6.4   3.5 | -18.6  -1.5  305  42 22   6.5   3.6
 22000 -16.7   1.9  305  38 20   6.4   3.5 | -16.7   1.9  305  39 20   6.5   3.6
 21000 -14.7   5.5  305  37 19   6.9   3.8 | -14.7   5.5  310  35 18   6.7   3.7
 20000 -12.7   9.1  305  36 18   6.9   3.8 | -12.8   9.0  310  32 16   6.8   3.7
 19500 -11.6  11.1  305  35 18   6.9   3.8 | -11.8  10.8  310  30 15   6.8   3.7
 19000 -10.6  12.9  305  35 18   6.5   3.6 | -10.8  12.6  310  28 14   6.9   3.8
 18500  -9.7  14.5  305  33 17   6.1   3.4 |  -9.7  14.5  305  30 15   7.0   3.8
 18000  -8.7  16.3  305  32 16   6.2   3.4 |  -8.6  16.5  305  31 16   7.1   3.9
 17500  -7.8  18.0  305  31 16   5.5   3.0 |  -7.6  18.3  305  31 16   5.4   3.0
 17000  -7.0  19.4  310  29 15   5.6   3.1 |  -6.8  19.8  300  29 15   5.6   3.1
 16500  -5.7  21.7  310  27 14   6.4   3.5 |  -5.4  22.3  300  27 14   6.7   3.7
 16000  -4.7  23.5  310  26 13   6.4   3.5 |  -4.4  24.1  300  26 13   6.6   3.6
 15500  -3.8  25.2  315  25 13   6.6   3.6 |  -3.4  25.9  295  25 13   7.6   4.2
 15000  -2.8  27.0  315  23 12   6.7   3.7 |  -2.2  28.0  295  24 13   7.7   4.2
 14500  -1.8  28.8  315  22 11   7.0   3.9 |  -1.1  30.0  295  24 12   8.0   4.4
 14000  -0.7  30.7  315  20 10   7.3   4.0 |   0.2  32.4  295  23 12   8.1   4.5
 13500   0.3  32.5  315  19 10   7.3   4.0 |   1.4  34.5  290  23 12   8.1   4.4
 13000   1.4  34.5  315  17  9   7.1   3.9 |   2.6  36.7  290  23 12   8.0   4.4
 12500   2.4  36.3  315  16  8   7.2   4.0 |   3.7  38.7  285  23 12   8.1   4.5
 12000   3.5  38.3  315  15  8   7.5   4.1 |   4.9  40.8  285  22 11   8.5   4.6
 11500   4.6  40.3  315  14  7   7.7   4.2 |   6.1  43.0  280  20 11   8.5   4.7
 11000   5.9  42.6  310  13  7   8.6   4.7 |   7.3  45.1  280  18  9   8.2   4.5
 10500   7.2  45.0  305  13  7   6.2   3.4 |   8.5  47.3  275  16  8   5.8   3.2
 10250   7.5  45.5  305  13  7   4.8   2.6 |   8.8  47.8  275  15  8   5.0   2.7
 10000   8.0  46.4  305  13  7   9.3   5.1 |   9.3  48.7  270  14  7   9.1   5.0
  9750   8.7  47.7  305  12  6  11.0   6.1 |  10.0  50.0  265  13  7   9.8   5.4
  9500   9.5  49.1  305  12  6   9.0   4.9 |  10.7  51.3  265  12  6   8.7   4.8
  9250  10.0  50.0  300  12  6   5.5   3.0 |  11.3  52.3  260  11  6   6.5   3.6
  9000  10.4  50.7  300  11  6   6.4   3.5 |  11.7  53.1  255  10  5   7.3   4.0
  8750  10.9  51.6  300   9  5   8.4   4.6 |  12.3  54.1  250  10  5   8.7   4.8
  8500  11.5  52.7  295   8  4   7.0   3.8 |  12.9  55.2  240   9  5   7.8   4.3
  8250  11.9  53.4  285   6  3   6.0   3.3 |  13.5  56.3  235   9  5   7.2   3.9
  8000  12.4  54.3  270   5  2   6.1   3.4 |  14.0  57.2  225   9  4   7.0   3.9
  7750  12.8  55.0  245   4  2   6.2   3.4 |  14.5  58.1  220   8  4   6.8   3.7
  7500  13.3  55.9  215   4  2   8.4   4.6 |  15.0  59.0  210   8  4   6.8   3.7
  7250  14.0  57.2  210   4  2  10.0   5.5 |  15.6  60.1  205   8  4   6.9   3.8
  7000  14.7  58.5  205   4  2   9.4   5.1 |  16.1  61.0  200   9  4   6.6   3.6
  6750  15.5  59.9  200   4  2   9.7   5.3 |  16.6  61.9  195   9  5   6.7   3.7
  6500  16.2  61.2  200   4  2  10.4   5.7 |  17.1  62.8  195   8  4   8.2   4.5
  6250  17.0  62.6  205   4  2  11.2   6.1 |  17.7  63.9  195   8  4   8.8   4.8
  6000  17.8  64.0  205   4  2   9.4   5.1 |  18.4  65.1  195   7  4   8.9   4.9
  5750  18.5  65.3  200   4  2  11.8   6.5 |  19.0  66.2  190   7  4   6.7   3.7
  5500  19.7  67.5  200   4  2  20.7  11.4 |  19.2  66.6  190   5  3   2.0   1.1
________________________________________________________________________________

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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