Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 171319
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0719 MDT Friday, October 17, 2014

This forecast is for Friday, October 17, 2014:

If the trigger temperature of 61.2 F/16.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 305 ft/min (1.6 m/s)
   Maximum height of thermals.................. 9885 ft MSL (4600 ft AGL)

Forecast maximum temperature................... 64.0 F/18.2 C
Time of trigger temperature.................... 1145 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................. 7540 ft MSL (2254 ft AGL)
Thermal soaring outlook for Saturday 10/18..... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... Becoming poor later today
Height of stable layer (12-18K ft MSL)......... 13654 ft MSL (8369 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 19315 ft MSL (14030 ft AGL)
Wave soaring outlook for Saturday 10/18........ Poor

Remarks... None

Sunrise/Sunset.................... 07:11:56 / 18:18:39 MDT
Total possible sunshine........... 11 hr 6 min 43 sec (666 min 43 sec)
Altitude of sun at 12:44:51 MDT... 40.83 degrees

Upper air data from rawinsonde observation taken on 10/17/2014 at 0600 MDT

Freezing level.................. 12951 ft MSL (7666 ft AGL)
Convective condensation level... 18249 ft MSL (12964 ft AGL)
Lifted condensation level....... 13315 ft MSL (8029 ft AGL)
Lifted index.................... +7.2
K index......................... +10.4

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  -65.4 -85.7   280   53   27  -0.7  -0.4   88.6 191.4    40.7      M    M
 45000  -63.7 -82.7   280   74   38   1.7   0.9   65.5 149.9    29.5      M    M
 40000  -58.1 -72.6   275   84   43   7.5   4.1   51.2 124.2    22.2      M    M
 38000  -55.2 -67.4   275   79   40   4.4   2.4   46.8 116.2    19.8      M    M
 36000  -50.8 -59.4   280   74   38   8.7   4.8   44.8 112.7    18.9      M    M
 34000  -45.3 -49.5   280   68   35   6.6   3.6   44.2 111.6    19.0      M    M
 32000  -41.7 -43.1   280   62   32   7.5   4.1   41.2 106.2    17.3      M    M
 30000  -35.8 -32.4   280   57   29   9.1   5.0   40.3 104.6    17.0      M    M
 29000  -33.7 -28.7   280   52   27   7.0   3.9   39.2 102.6    16.4      M    M
 28000  -31.1 -24.0   280   48   25   8.2   4.5   38.8 101.9    16.3      M    M
 27000  -28.8 -19.8   280   44   22   8.1   4.4   38.0 100.4    15.9      M    M
 26000  -26.4 -15.5   280   39   20   8.1   4.5   37.4  99.3    15.6      M    M
 25000  -23.9 -11.0   280   35   18   8.1   4.4   36.8  98.2    15.3      M    M
 24000  -21.8  -7.2   280   33   17   6.2   3.4   35.8  96.4    14.6      M    M
 23000  -19.6  -3.3   285   33   17   7.9   4.4   35.0  95.0    14.1      M    M
 22000  -17.3   0.9   290   33   17   8.6   4.7   34.2  93.6    13.6      M    M
 21000  -14.7   5.5   295   34   17   8.3   4.6   33.8  92.8    13.5      M    M
 20000  -12.4   9.7   295   37   19   7.0   3.9   33.0  91.5    13.0      M    M
 19500  -11.4  11.5   290   39   20   8.1   4.4   32.5  90.5    12.5      M    M
 19000  -10.2  13.6   285   41   21   6.4   3.5   32.2  90.0    12.4      M    M
 18500   -9.2  15.4   285   39   20   7.0   3.9   31.6  88.9    11.9      M    M
 18000   -8.2  17.2   285   38   19   7.2   4.0   31.1  88.1    11.6      M    M
 17500   -7.4  18.7   285   36   19   2.5   1.4   30.4  86.7    11.0      M    M
 17000   -7.2  19.0   285   35   18   2.9   1.6   29.1  84.4     9.7      M    M
 16500   -6.7  19.9   285   34   17   6.5   3.6   28.2  82.7     8.9      M    M
 16000   -5.5  22.1   285   32   17   7.5   4.1   27.8  82.1     8.6      M    M
 15500   -4.4  24.1   285   31   16   7.8   4.3   27.5  81.4     8.3      M    M
 15000   -3.0  26.6   290   30   15   5.8   3.2   26.6  80.0     7.6      M    M
 14500   -2.2  28.0   295   29   15   5.7   3.2   26.0  78.8     7.0      M    M
 14000   -1.1  30.0   295   27   14   5.2   2.9   25.5  78.0     6.7      M    M
 13500   -0.9  30.4   290   25   13   2.0   1.1   24.0  75.3     5.4      M    M
 13000    0.1  32.2   290   22   11   8.3   4.5   23.6  74.4     5.0      M    M
 12500    1.3  34.3   285   19   10   8.2   4.5   23.3  73.9     4.7      M    M
 12000    2.5  36.5   280   17    9   8.2   4.5   23.1  73.5     4.5      M    M
 11500    3.7  38.7   275   14    7   8.1   4.5   22.8  73.1     4.3      M    M
 11000    4.8  40.6   270   11    6   5.9   3.3   22.5  72.6     4.0      M    M
 10500    5.3  41.5   260    8    4   4.0   2.2   21.7  71.0     3.0      M    M
 10250    5.1  41.2   250    7    4 -11.5  -6.3   20.8  69.4     2.1      M    M
 10000    4.0  39.2   225    7    4 -10.0  -5.5   18.8  65.8     0.3      M    M
  9750    3.9  39.0   205    9    4  -0.2  -0.1   17.9  64.2    -0.6    302  1.5
  9500    3.8  38.8   195   10    5   2.8   1.5   17.0  62.6    -1.4    297  1.5
  9250    4.4  39.9   185   13    7   9.4   5.2   16.9  62.4    -1.5    272  1.4
  9000    5.0  41.0   180   15    8   7.6   4.2   16.8  62.2    -1.7    247  1.3
  8750    5.6  42.1   180   13    7   8.1   4.4   16.6  61.9    -1.8    222  1.1
  8500    6.2  43.2   180   12    6   8.0   4.4   16.5  61.7    -2.0    197  1.0
  8250    6.8  44.2   180   10    5   7.8   4.3   16.3  61.4    -2.1    172  0.9
  8000    7.3  45.1   180    9    5   8.8   4.8   16.2  61.2    -2.2    147  0.7
  7750    7.9  46.2   175    8    4   5.2   2.9   16.1  60.9    -2.4    122  0.6
  7500    7.9  46.2   170    6    3  -4.8  -2.6   15.4  59.6    -3.1    114  0.6
  7250    7.5  45.5   165    5    3  -4.2  -2.3   14.1  57.4    -4.3    121  0.6
  7000    7.5  45.5   150    4    2   1.0   0.5   13.3  56.0    -5.1    114  0.6
  6750    7.6  45.7   165    2    1   0.2   0.1   12.6  54.7    -5.7    104  0.5
  6500    7.5  45.5   215    2    1  -0.7  -0.4   11.9  53.4    -6.5     97  0.5
  6250    7.4  45.3   265    2    1  -1.2  -0.7   11.1  51.9    -7.3     92  0.5
  6000    7.3  45.1   285    4    2  -0.8  -0.4   10.2  50.4    -8.2     88  0.4
  5750    7.2  45.0   270    3    1  -1.9  -1.0    9.4  49.0    -9.0     84  0.4
  5500    6.7  44.1   235    2    1 -13.3  -7.3    8.2  46.8   -10.3     92  0.5

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

           10/17/2014 at 0900 MDT          |       10/17/2014 at 1200 MDT
                                           |
K index... +13.6  LI... +5.3               | K index... +11.7  LI... +5.0
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 -66.0 -86.8  280  52 27   0.2   0.1 | -66.0 -86.8  280  48 25   0.1   0.1
 45000 -64.8 -84.6  275  74 38   4.0   2.2 | -64.9 -84.8  275  73 37   3.7   2.0
 40000 -58.9 -74.0  280  76 39   4.8   2.6 | -59.5 -75.1  275  68 35   4.8   2.6
 38000 -54.6 -66.3  280  70 36   7.2   4.0 | -55.0 -67.0  275  64 33   7.7   4.2
 36000 -50.3 -58.5  285  65 33   7.2   4.0 | -50.3 -58.5  280  61 31   7.7   4.2
 34000 -45.6 -50.1  285  60 31   8.0   4.4 | -45.5 -49.9  280  59 30   8.2   4.5
 32000 -40.2 -40.4  285  56 29   8.1   4.4 | -40.0 -40.0  285  57 29   8.3   4.5
 30000 -35.5 -31.9  290  50 26   7.9   4.3 | -35.2 -31.4  285  53 27   7.8   4.3
 29000 -33.1 -27.6  290  47 24   7.9   4.3 | -32.8 -27.0  285  50 26   7.8   4.3
 28000 -30.7 -23.3  290  44 23   7.9   4.4 | -30.5 -22.9  285  47 24   7.9   4.3
 27000 -28.5 -19.3  290  42 22   7.3   4.0 | -28.3 -18.9  285  44 23   7.3   4.0
 26000 -26.3 -15.3  290  40 21   7.4   4.0 | -26.1 -15.0  285  41 21   7.3   4.0
 25000 -24.1 -11.4  290  39 20   7.4   4.1 | -23.9 -11.0  285  37 19   7.4   4.0
 24000 -21.9  -7.4  290  37 19   7.8   4.3 | -21.7  -7.1  280  35 18   7.6   4.2
 23000 -19.5  -3.1  290  35 18   7.8   4.3 | -19.4  -2.9  280  35 18   7.6   4.2
 22000 -17.2   1.0  285  34 17   7.9   4.3 | -17.1   1.2  280  34 17   7.6   4.2
 21000 -14.9   5.2  285  33 17   7.6   4.2 | -14.9   5.2  280  34 17   7.4   4.1
 20000 -12.6   9.3  285  32 17   7.6   4.2 | -12.7   9.1  285  33 17   7.4   4.1
 19500 -11.5  11.3  285  32 16   7.6   4.2 | -11.5  11.3  285  33 17   7.4   4.0
 19000 -10.3  13.5  285  32 16   7.0   3.8 | -10.4  13.3  285  33 17   7.1   3.9
 18500  -9.5  14.9  285  32 17   5.4   3.0 |  -9.5  14.9  285  33 17   6.5   3.6
 18000  -8.7  16.3  285  33 17   5.5   3.0 |  -8.5  16.7  285  32 17   6.5   3.6
 17500  -7.9  17.8  285  33 17   5.6   3.1 |  -7.6  18.3  290  32 16   6.1   3.4
 17000  -7.1  19.2  285  32 16   5.7   3.1 |  -6.7  19.9  290  31 16   6.1   3.4
 16500  -6.3  20.7  285  30 16   5.8   3.2 |  -5.8  21.6  290  30 16   6.0   3.3
 16000  -5.5  22.1  290  30 15   5.9   3.3 |  -4.5  23.9  290  28 15   5.9   3.2
 15500  -4.2  24.4  290  29 15   5.7   3.1 |  -3.7  25.3  295  27 14   6.1   3.3
 15000  -3.3  26.1  295  27 14   5.5   3.0 |  -2.8  27.0  295  26 13   6.1   3.4
 14500  -2.5  27.5  295  25 13   6.0   3.3 |  -1.8  28.8  295  24 13   6.2   3.4
 14000  -1.4  29.5  295  24 12   7.0   3.8 |  -0.9  30.4  295  23 12   6.4   3.5
 13500  -0.4  31.3  300  23 12   7.0   3.8 |   0.1  32.2  295  22 11   6.5   3.5
 13000   0.6  33.1  300  21 11   7.3   4.0 |   1.0  33.8  295  20 10   6.8   3.8
 12500   1.7  35.1  300  20 10   7.3   4.0 |   2.0  35.6  295  19 10   6.8   3.8
 12000   2.7  36.9  300  19 10   7.0   3.8 |   3.0  37.4  300  17  9   7.2   4.0
 11500   3.8  38.8  300  17  9   7.2   3.9 |   4.1  39.4  300  16  8   7.3   4.0
 11000   4.6  40.3  295  15  8   4.8   2.6 |   5.1  41.2  300  14  7   6.0   3.3
 10500   5.4  41.7  295  13  7   5.2   2.9 |   6.0  42.8  300  13  7   6.2   3.4
 10250   5.7  42.3  295  12  6   2.2   1.2 |   6.4  43.5  300  12  6   3.7   2.0
 10000   5.8  42.4  295  11  6   2.0   1.1 |   6.6  43.9  300  12  6   4.1   2.2
  9750   6.0  42.8  290  10  5   4.4   2.4 |   7.0  44.6  295  11  5   6.3   3.5
  9500   6.3  43.3  290   8  4   3.6   2.0 |   7.5  45.5  295   9  5   5.3   2.9
  9250   6.5  43.7  285   7  3   3.0   1.7 |   7.8  46.0  295   8  4   2.6   1.4
  9000   6.7  44.1  280   6  3   2.3   1.3 |   7.9  46.2  295   8  4   1.2   0.7
  8750   6.9  44.4  275   5  2   2.2   1.2 |   8.0  46.4  295   7  4   2.3   1.3
  8500   7.0  44.6  260   4  2   2.1   1.2 |   8.1  46.6  290   6  3   1.6   0.9
  8250   7.2  45.0  240   3  2   2.2   1.2 |   8.2  46.8  290   5  3   0.3   0.2
  8000   7.3  45.1  215   3  2   2.0   1.1 |   8.2  46.8  280   4  2   0.0   0.0
  7750   7.5  45.5  195   4  2   2.8   1.5 |   8.2  46.8  265   3  2   0.0   0.0
  7500   7.6  45.7  185   5  3   0.5   0.3 |   8.1  46.6  230   3  1   0.4   0.2
  7250   7.5  45.5  185   5  3  -2.1  -1.1 |   8.2  46.8  220   3  1   0.9   0.5
  7000   7.4  45.3  185   5  2  -1.1  -0.6 |   8.2  46.8  210   2  1   0.3   0.2
  6750   7.3  45.1  190   4  2  -2.2  -1.2 |   8.3  46.9  200   2  1   1.6   0.9
  6500   7.0  44.6  205   3  2  -5.6  -3.1 |   8.5  47.3  210   1  1   6.3   3.5
  6250   6.5  43.7  230   3  1  -8.2  -4.5 |   9.1  48.4  235   1  0   8.3   4.5
  6000   5.9  42.6  260   3  1  -4.1  -2.2 |   9.7  49.5  320   1  0   8.1   4.4
  5750   6.0  42.8  280   3  2   5.3   2.9 |  10.4  50.7  340   1  1  13.7   7.5
  5500   6.5  43.7  285   3  1  10.0   5.5 |  11.8  53.2  340   1  1  21.5  11.8

           10/17/2014 at 1500 MDT          |       10/17/2014 at 1800 MDT
                                           |
K index... +8.4  LI... +3.1                | K index... +12.1  LI... +3.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -66.0 -86.8  275  46 24   0.5   0.3 | -65.9 -86.6  280  44 23   0.4   0.2
 45000 -64.6 -84.3  275  68 35   3.3   1.8 | -64.5 -84.1  275  61 31   3.2   1.8
 40000 -59.7 -75.5  275  61 31   4.5   2.5 | -59.7 -75.5  280  56 29   4.6   2.5
 38000 -55.1 -67.2  275  59 30   7.8   4.3 | -54.9 -66.8  275  59 31   8.2   4.5
 36000 -50.4 -58.7  275  57 29   7.8   4.3 | -50.0 -58.0  275  63 32   8.2   4.5
 34000 -45.5 -49.9  280  55 28   8.3   4.5 | -45.2 -49.4  275  59 31   7.8   4.3
 32000 -39.9 -39.8  280  54 28   8.3   4.6 | -40.0 -40.0  285  50 26   7.8   4.3
 30000 -35.1 -31.2  285  52 27   8.1   4.4 | -35.2 -31.4  290  45 23   8.0   4.4
 29000 -32.7 -26.9  285  50 26   8.1   4.4 | -32.8 -27.0  290  43 22   8.0   4.4
 28000 -30.2 -22.4  290  49 25   8.2   4.5 | -30.5 -22.9  295  41 21   8.1   4.4
 27000 -28.0 -18.4  290  47 24   7.4   4.1 | -28.2 -18.8  295  40 21   7.5   4.1
 26000 -25.8 -14.4  285  45 23   7.4   4.1 | -25.9 -14.6  290  40 20   7.5   4.1
 25000 -23.6 -10.5  285  43 22   7.4   4.1 | -23.7 -10.7  290  39 20   7.6   4.2
 24000 -21.3  -6.3  285  40 21   8.0   4.4 | -21.3  -6.3  290  38 19   8.2   4.5
 23000 -18.9  -2.0  280  38 20   8.0   4.4 | -18.8  -1.8  290  36 18   8.2   4.5
 22000 -16.4   2.5  280  36 19   8.0   4.4 | -16.3   2.7  285  34 17   8.3   4.6
 21000 -14.4   6.1  280  35 18   6.3   3.4 | -14.3   6.3  290  32 17   5.7   3.1
 20000 -12.5   9.5  285  34 18   6.2   3.4 | -12.6   9.3  295  31 16   5.6   3.1
 19500 -11.6  11.1  290  34 18   6.2   3.4 | -11.8  10.8  295  31 16   5.6   3.1
 19000 -10.6  12.9  290  34 17   6.3   3.5 | -10.9  12.4  300  31 16   5.7   3.1
 18500  -9.7  14.5  290  33 17   6.5   3.5 | -10.1  13.8  300  29 15   5.8   3.2
 18000  -8.7  16.3  290  31 16   6.5   3.5 |  -9.3  15.3  300  27 14   5.7   3.1
 17500  -7.7  18.1  295  30 15   6.8   3.7 |  -8.4  16.9  300  25 13   7.2   3.9
 17000  -6.7  19.9  295  29 15   6.8   3.8 |  -7.3  18.9  300  26 13   7.2   4.0
 16500  -5.7  21.7  295  29 15   6.7   3.7 |  -6.2  20.8  295  26 13   6.9   3.8
 16000  -4.3  24.3  295  28 14   6.4   3.5 |  -4.8  23.4  290  25 13   6.4   3.5
 15500  -3.4  25.9  295  27 14   6.6   3.6 |  -3.9  25.0  290  24 12   7.2   3.9
 15000  -2.4  27.7  295  26 13   6.7   3.7 |  -2.8  27.0  285  23 12   7.6   4.2
 14500  -1.4  29.5  295  25 13   6.7   3.7 |  -1.7  28.9  280  22 11   7.6   4.2
 14000  -0.4  31.3  295  24 13   6.9   3.8 |  -0.6  30.9  280  20 10   7.4   4.1
 13500   0.6  33.1  290  23 12   6.9   3.8 |   0.4  32.7  280  17  9   7.4   4.1
 13000   1.5  34.7  290  22 11   6.7   3.7 |   1.5  34.7  275  15  7   6.9   3.8
 12500   2.5  36.5  290  19 10   6.8   3.7 |   2.5  36.5  275  12  6   7.0   3.8
 12000   3.5  38.3  285  17  9   7.7   4.2 |   3.5  38.3  270   9  5   6.3   3.5
 11500   4.6  40.3  285  14  7   7.7   4.2 |   4.4  39.9  260   7  4   6.4   3.5
 11000   5.6  42.1  285  11  6   6.6   3.6 |   5.3  41.5  250   6  3   5.2   2.8
 10500   6.7  44.1  285   8  4   6.8   3.7 |   6.1  43.0  240   4  2   5.2   2.8
 10250   7.1  44.8  285   7  4   3.5   1.9 |   6.4  43.5  230   3  2   2.9   1.6
 10000   7.3  45.1  285   7  3   4.3   2.3 |   6.6  43.9  225   3  2   4.1   2.2
  9750   7.8  46.0  285   6  3   7.4   4.1 |   7.1  44.8  200   3  1   6.4   3.5
  9500   8.3  46.9  285   5  2   6.5   3.6 |   7.5  45.5  180   3  1   5.7   3.1
  9250   8.8  47.8  285   4  2   3.8   2.1 |   7.9  46.2  155   3  2   3.8   2.1
  9000   8.9  48.0  280   3  2   3.0   1.6 |   8.1  46.6  145   4  2   4.1   2.3
  8750   9.3  48.7  280   2  1   4.6   2.6 |   8.4  47.1  135   5  3   5.9   3.2
  8500   9.6  49.3  270   1  1   3.9   2.1 |   8.8  47.8  125   7  3   5.8   3.2
  8250   9.8  49.6  000   0  0   2.8   1.5 |   9.2  48.6  120   7  3   6.6   3.6
  8000  10.0  50.0  140   1  1   2.6   1.4 |   9.7  49.5  110   6  3   6.9   3.8
  7750  10.2  50.4  125   2  1   2.7   1.5 |  10.2  50.4  100   6  3   6.8   3.7
  7500  10.4  50.7  115   2  1   4.0   2.2 |  10.7  51.3  095   6  3   7.7   4.2
  7250  10.7  51.3  100   2  1   5.5   3.0 |  11.3  52.3  090   6  3   8.6   4.7
  7000  11.1  52.0  080   2  1   5.3   2.9 |  12.0  53.6  080   6  3   8.4   4.6
  6750  11.5  52.7  060   2  1   6.5   3.6 |  12.6  54.7  070   5  3   8.3   4.6
  6500  12.0  53.6  055   2  1   9.7   5.3 |  13.2  55.8  065   5  3   8.7   4.8
  6250  12.8  55.0  050   2  1  11.5   6.3 |  13.9  57.0  055   5  3   8.8   4.8
  6000  13.6  56.5  040   2  1   9.6   5.3 |  14.5  58.1  045   5  3   9.2   5.1
  5750  14.4  57.9  035   2  1  11.9   6.5 |  15.2  59.4  035   6  3   7.4   4.0
  5500  15.6  60.1  035   2  1  20.3  11.1 |  15.5  59.9  030   4  2   2.8   1.5
________________________________________________________________________________

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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