Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 301241
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0641 MDT Thursday, October 30, 2014

This forecast is for Thursday, October 30, 2014:

If the trigger temperature of 57.5 F/14.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 380 ft/min (1.9 m/s)
   Maximum height of thermals.................. 10864 ft MSL (5579 ft AGL)

Forecast maximum temperature................... 63.0 F/17.7 C
Time of trigger temperature.................... 1115 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................. 9150 ft MSL (3865 ft AGL)
Thermal soaring outlook for Friday 10/31....... Good

Wave Soaring Index............................. Good
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16372 ft MSL (11087 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 21546 ft MSL (16261 ft AGL)
Wave soaring outlook for Friday 10/31.......... Fair

Remarks...

Sunrise/Sunset.................... 07:26:04 / 17:59:53 MDT
Total possible sunshine........... 10 hr 33 min 50 sec (633 min 50 sec)
Altitude of sun at 12:43:14 MDT... 36.33 degrees

Upper air data from rawinsonde observation taken on 10/30/2014 at 0600 MDT

Freezing level.................. 11133 ft MSL (5848 ft AGL)
Convective condensation level... 18778 ft MSL (13493 ft AGL)
Lifted condensation level....... 14627 ft MSL (9342 ft AGL)
Lifted index.................... +9.1
K index......................... +5.9

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  -66.9 -88.4   275   31   16   6.9   3.8   83.9 183.0    38.5      M    M
 45000  -57.3 -71.1   275   33   17   8.4   4.6   75.4 167.7    36.0      M    M
 40000  -49.6 -57.3   285   47   24   5.2   2.8   64.6 148.2    31.3      M    M
 38000  -46.6 -51.9   300   50   26   3.1   1.7   60.4 140.7    29.3      M    M
 36000  -49.2 -56.6   310   55   28  -0.2  -0.1   48.1 118.6    21.5      M    M
 34000  -46.4 -51.5   320   59   31   6.0   3.3   43.8 110.8    19.0      M    M
 32000  -41.6 -42.9   325   63   33   8.5   4.7   41.3 106.4    17.7      M    M
 30000  -37.7 -35.9   330   61   31   6.6   3.6   38.7 101.6    16.2      M    M
 29000  -35.7 -32.3   330   61   31   8.4   4.6   37.5  99.5    15.5      M    M
 28000  -32.9 -27.2   325   61   31   9.2   5.0   37.1  98.8    15.4      M    M
 27000  -30.2 -22.4   325   61   31   9.2   5.0   36.8  98.3    15.4      M    M
 26000  -27.4 -17.3   320   61   31   9.1   5.0   36.7  98.1    15.4      M    M
 25000  -25.1 -13.2   320   61   31   5.7   3.1   36.2  97.1    15.1      M    M
 24000  -23.1  -9.6   320   59   31   9.0   4.9   35.0  94.9    14.3      M    M
 23000  -20.8  -5.4   315   60   31   6.2   3.4   34.1  93.5    13.9      M    M
 22000  -20.1  -4.2   315   62   32   1.7   0.9   31.5  88.8    11.8      M    M
 21000  -18.0  -0.4   310   63   32   8.5   4.7   30.6  87.1    11.1      M    M
 20000  -15.3   4.5   310   56   29   9.0   4.9   30.3  86.6    11.0      M    M
 19500  -14.0   6.8   310   54   28   8.8   4.8   30.2  86.3    10.9      M    M
 19000  -13.2   8.2   315   52   27   4.4   2.4   29.4  85.0    10.3      M    M
 18500  -12.1  10.2   315   52   27   8.2   4.5   29.0  84.2     9.9      M    M
 18000  -11.0  12.2   315   52   27   7.5   4.1   28.7  83.6     9.6      M    M
 17500   -9.9  14.2   315   52   27   7.6   4.2   28.3  82.9     9.3      M    M
 17000   -8.8  16.2   315   52   27   7.9   4.3   27.9  82.2     9.1      M    M
 16500   -8.0  17.6   315   52   27   0.3   0.2   27.2  81.0     8.5      M    M
 16000   -8.4  16.9   315   51   26  -2.0  -1.1   24.3  75.7     5.9      M    M
 15500   -8.1  17.4   315   47   24   4.5   2.5   22.9  73.2     4.8      M    M
 15000   -7.4  18.7   315   43   22   5.1   2.8   22.0  71.7     4.0      M    M
 14500   -6.7  19.9   310   40   21   5.3   2.9   21.3  70.3     3.3      M    M
 14000   -5.9  21.4   305   38   19   5.2   2.9   20.5  68.9     2.6      M    M
 13500   -5.1  22.8   300   37   19   5.2   2.8   19.8  67.6     2.0      M    M
 13000   -4.5  23.9   295   36   18   5.0   2.8   19.0  66.1     1.2      M    M
 12500   -3.4  25.9   295   35   18   8.9   4.9   18.6  65.5     0.8      M    M
 12000   -2.1  28.2   290   34   17   8.7   4.8   18.4  65.2     0.7      M    M
 11500   -0.8  30.6   295   30   16   8.9   4.9   18.2  64.8     0.5      M    M
 11000    0.3  32.5   295   27   14   4.6   2.5   17.9  64.2     0.2      M    M
 10500    0.9  33.6   300   24   12   3.7   2.0   16.9  62.4    -0.8    354  1.8
 10250    1.1  34.0   300   20   10   3.4   1.8   16.4  61.6    -1.2    339  1.7
 10000    1.4  34.5   305   16    8   3.4   1.9   15.9  60.6    -1.7    324  1.6
  9750    1.6  34.9   315   14    7   3.1   1.7   15.4  59.7    -2.2    309  1.6
  9500    1.9  35.4   320   13    7   4.4   2.4   14.9  58.8    -2.7    295  1.5
  9250    2.3  36.1   330   12    6   8.0   4.4   14.6  58.3    -3.0    274  1.4
  9000    3.0  37.4   340   12    6   9.0   4.9   14.6  58.2    -3.1    246  1.3
  8750    3.7  38.7   355   13    7   9.9   5.5   14.5  58.1    -3.1    219  1.1
  8500    4.3  39.7   010   15    8   5.1   2.8   14.4  58.0    -3.2    192  1.0
  8250    4.4  39.9   020   17    9  -1.1  -0.6   13.7  56.7    -3.9    183  0.9
  8000    4.4  39.9   025   20   10   3.0   1.7   13.0  55.4    -4.6    174  0.9
  7750    4.8  40.6   025   18    9   5.8   3.2   12.7  54.8    -5.0    155  0.8
  7500    5.2  41.4   020   17    9   4.7   2.6   12.3  54.1    -5.3    136  0.7
  7250    5.6  42.1   020   15    8   6.3   3.5   12.0  53.5    -5.7    117  0.6
  7000    6.1  43.0   015   14    7   7.9   4.3   11.8  53.2    -5.9     93  0.5
  6750    6.7  44.1   015   12    6   7.6   4.2   11.6  52.9    -6.0     69  0.3
  6500    7.3  45.1   015   10    5   7.7   4.2   11.5  52.6    -6.2     44  0.2
  6250    7.8  46.0   015    7    4   7.6   4.2   11.3  52.3    -6.4     20  0.1
  6000    8.4  47.1   010    5    3   8.1   4.4   11.2  52.1    -6.6      M    M
  5750    9.0  48.2   360    3    2   6.2   3.4   11.0  51.8    -6.7      M    M
  5500    8.6  47.5   325    2    1 -22.7 -12.4    9.9  49.9    -7.8      M    M

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

           10/30/2014 at 0900 MDT          |       10/30/2014 at 1200 MDT
                                           |
K index... +7.0  LI... +8.0                | K index... +5.2  LI... +8.9
CAPE... 0.0  CIN... -0.0                   | 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 -63.9 -83.0  275  27 14   3.5   1.9 | -64.1 -83.4  265  32 17   3.6   2.0
 45000 -58.2 -72.8  280  32 17   5.3   2.9 | -58.4 -73.1  270  37 19   3.6   2.0
 40000 -50.1 -58.2  290  43 22   4.4   2.4 | -53.0 -63.4  300  42 22   3.6   2.0
 38000 -49.0 -56.2  310  45 23   1.7   0.9 | -50.8 -59.4  310  43 22   3.5   1.9
 36000 -48.0 -54.4  320  51 26   1.7   0.9 | -48.7 -55.7  325  46 24   3.5   1.9
 34000 -45.5 -49.9  330  55 28   6.4   3.5 | -45.5 -49.9  330  50 26   6.7   3.7
 32000 -41.2 -42.2  330  55 28   6.4   3.5 | -41.0 -41.8  330  55 28   6.8   3.7
 30000 -36.8 -34.2  325  54 28   7.7   4.2 | -36.5 -33.7  330  56 29   7.8   4.3
 29000 -34.5 -30.1  325  54 28   7.7   4.2 | -34.2 -29.6  325  56 29   7.8   4.3
 28000 -32.2 -26.0  325  53 27   7.8   4.3 | -31.9 -25.4  325  57 29   7.8   4.3
 27000 -29.9 -21.8  325  53 27   7.5   4.1 | -29.7 -21.5  325  56 29   7.3   4.0
 26000 -27.7 -17.9  325  53 27   7.5   4.1 | -27.5 -17.5  320  55 28   7.3   4.0
 25000 -25.5 -13.9  325  53 27   7.5   4.1 | -25.3 -13.5  320  54 28   7.3   4.0
 24000 -23.3  -9.9  320  53 27   7.3   4.0 | -23.1  -9.6  320  53 27   7.6   4.2
 23000 -21.1  -6.0  320  53 27   7.3   4.0 | -20.8  -5.4  320  52 27   7.6   4.2
 22000 -18.9  -2.0  320  53 27   7.3   4.0 | -18.6  -1.5  320  52 27   7.7   4.2
 21000 -16.9   1.6  320  52 27   6.7   3.7 | -16.5   2.3  320  50 26   6.7   3.7
 20000 -14.9   5.2  320  51 26   6.7   3.7 | -14.5   5.9  320  48 25   6.7   3.7
 19500 -13.9   7.0  320  50 26   6.7   3.7 | -13.5   7.7  320  47 24   6.7   3.7
 19000 -12.9   8.8  320  49 25   6.8   3.7 | -12.5   9.5  320  46 24   6.2   3.4
 18500 -11.9  10.6  320  48 25   7.1   3.9 | -11.7  10.9  320  45 23   5.5   3.0
 18000 -10.8  12.6  320  46 24   7.3   4.0 | -10.8  12.6  320  44 23   5.5   3.0
 17500  -9.9  14.2  320  45 23   4.9   2.7 | -10.0  14.0  325  42 22   5.8   3.2
 17000  -9.2  15.4  325  44 23   4.8   2.6 |  -9.2  15.4  325  40 21   5.8   3.2
 16500  -8.5  16.7  325  43 22   4.5   2.4 |  -8.3  17.1  325  38 20   4.6   2.5
 16000  -7.6  18.3  325  41 21   4.0   2.2 |  -7.8  18.0  325  37 19   3.6   2.0
 15500  -6.9  19.6  325  39 20   4.3   2.3 |  -7.0  19.4  330  35 18   4.5   2.4
 15000  -6.3  20.7  325  37 19   4.3   2.4 |  -6.2  20.8  330  33 17   4.7   2.6
 14500  -5.6  21.9  325  36 18   4.1   2.3 |  -5.5  22.1  330  31 16   5.2   2.9
 14000  -5.0  23.0  325  33 17   3.9   2.1 |  -4.6  23.7  330  30 15   5.6   3.1
 13500  -4.5  23.9  320  31 16   4.0   2.2 |  -3.8  25.2  330  28 14   5.4   3.0
 13000  -3.9  25.0  320  29 15   4.3   2.4 |  -3.0  26.6  330  26 13   5.0   2.8
 12500  -3.3  26.1  320  27 14   4.4   2.4 |  -2.2  28.0  330  24 12   5.0   2.8
 12000  -2.6  27.3  320  24 12   4.8   2.6 |  -1.5  29.3  325  22 11   5.1   2.8
 11500  -1.9  28.6  320  21 11   5.0   2.7 |  -0.8  30.6  325  19 10   5.2   2.9
 11000  -1.1  30.0  320  19 10   5.8   3.2 |   0.0  32.0  325  16  8   5.5   3.0
 10500  -0.3  31.5  325  16  8   5.7   3.1 |   0.8  33.4  320  14  7   5.3   2.9
 10250   0.1  32.2  325  16  8   4.6   2.5 |   1.2  34.2  320  13  7   4.4   2.4
 10000   0.4  32.7  325  15  8   6.6   3.6 |   1.5  34.7  320  12  6   6.1   3.4
  9750   1.1  34.0  325  14  7   9.1   5.0 |   2.0  35.6  320  11  6   7.9   4.3
  9500   1.7  35.1  330  13  7   7.4   4.1 |   2.5  36.5  315  10  5   6.9   3.8
  9250   2.2  36.0  330  12  6   6.1   3.3 |   3.0  37.4  315   9  5   6.1   3.4
  9000   2.7  36.9  330  11  6   7.2   3.9 |   3.5  38.3  310   8  4   7.0   3.8
  8750   3.3  37.9  335  11  5   8.9   4.9 |   4.0  39.2  305   7  4   8.0   4.4
  8500   3.9  39.0  335  10  5   7.7   4.2 |   4.6  40.3  300   6  3   6.7   3.7
  8250   4.4  39.9  340  10  5   6.1   3.4 |   5.0  41.0  295   5  3   5.5   3.0
  8000   4.9  40.8  345   9  5   7.1   3.9 |   5.4  41.7  290   5  2   6.5   3.6
  7750   5.5  41.9  350   9  5   7.9   4.4 |   6.0  42.8  285   4  2   7.5   4.1
  7500   6.1  43.0  355   9  5   7.3   4.0 |   6.5  43.7  280   3  2   6.9   3.8
  7250   6.6  43.9  360   9  4   6.8   3.7 |   7.0  44.6  265   2  1   6.3   3.5
  7000   7.1  44.8  005   8  4   6.5   3.5 |   7.5  45.5  230   1  1   6.9   3.8
  6750   7.5  45.5  005   8  4   5.0   2.8 |   8.1  46.6  220   1  1   9.1   5.0
  6500   7.9  46.2  360   6  3   4.0   2.2 |   8.8  47.8  200   1  1  10.2   5.6
  6250   8.2  46.8  355   4  2   5.8   3.2 |   9.6  49.3  185   1  1  10.0   5.5
  6000   8.6  47.5  340   3  1  -0.4  -0.2 |  10.3  50.5  175   2  1   9.7   5.3
  5750   8.0  46.4  280   3  1 -10.9  -6.0 |  11.1  52.0  170   2  1  13.4   7.4
  5500   7.1  44.8  235   2  1  -9.8  -5.4 |  12.4  54.3  170   2  1  20.9  11.5

           10/30/2014 at 1500 MDT          |       10/30/2014 at 1800 MDT
                                           |
K index... +7.9  LI... +7.4                | K index... +10.6  LI... +5.7
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 -63.8 -82.8  270  35 18   3.6   2.0 | -64.4 -83.9  280  37 19   4.0   2.2
 45000 -58.7 -73.7  280  40 21   1.7   0.9 | -59.0 -74.2  290  42 22   1.2   0.7
 40000 -56.2 -69.2  305  40 20   3.1   1.7 | -57.1 -70.8  305  41 21   3.1   1.7
 38000 -52.9 -63.2  310  40 21   5.5   3.0 | -53.7 -64.7  305  41 21   5.8   3.2
 36000 -49.6 -57.3  315  41 21   5.5   3.0 | -50.2 -58.4  305  42 22   5.8   3.2
 34000 -45.7 -50.3  320  44 23   7.4   4.1 | -46.2 -51.2  310  43 22   7.4   4.1
 32000 -41.2 -42.2  330  50 26   7.4   4.1 | -41.7 -43.1  320  44 23   7.4   4.1
 30000 -36.0 -32.8  330  53 27   8.0   4.4 | -37.0 -34.6  320  45 23   8.1   4.4
 29000 -33.6 -28.5  330  53 27   8.0   4.4 | -34.0 -29.2  325  45 23   8.1   4.4
 28000 -31.3 -24.3  330  54 28   8.1   4.4 | -31.6 -24.9  325  45 23   8.1   4.4
 27000 -29.0 -20.2  325  53 27   7.4   4.1 | -29.2 -20.6  325  46 24   8.2   4.5
 26000 -26.8 -16.2  325  53 27   7.4   4.1 | -26.7 -16.1  325  46 24   8.2   4.5
 25000 -24.6 -12.3  320  53 27   7.4   4.1 | -24.3 -11.7  325  47 24   8.2   4.5
 24000 -22.4  -8.3  320  53 27   7.2   4.0 | -22.0  -7.6  325  47 24   7.5   4.1
 23000 -20.2  -4.4  320  53 27   7.2   4.0 | -19.7  -3.5  325  47 24   7.5   4.1
 22000 -18.0  -0.4  315  52 27   7.3   4.0 | -17.5   0.5  320  48 25   7.6   4.2
 21000 -16.0   3.2  315  51 26   6.3   3.5 | -15.6   3.9  320  47 24   5.8   3.2
 20000 -14.2   6.4  315  49 25   6.3   3.5 | -13.8   7.2  320  46 24   5.8   3.2
 19500 -13.2   8.2  315  48 25   6.3   3.4 | -13.0   8.6  320  46 24   5.8   3.2
 19000 -12.3   9.9  315  47 24   5.9   3.3 | -12.1  10.2  320  46 24   5.9   3.2
 18500 -11.5  11.3  315  45 23   5.5   3.0 | -11.2  11.8  320  44 23   6.0   3.3
 18000 -10.7  12.7  315  43 22   5.6   3.1 | -10.3  13.5  315  43 22   6.2   3.4
 17500  -9.9  14.2  315  41 21   5.2   2.8 |  -9.5  14.9  315  41 21   4.8   2.6
 17000  -9.2  15.4  315  39 20   5.3   2.9 |  -8.8  16.2  315  38 20   5.0   2.8
 16500  -8.5  16.7  320  37 19   5.1   2.8 |  -8.1  17.4  315  35 18   4.8   2.7
 16000  -7.7  18.1  320  35 18   5.7   2.7 |  -7.4  18.7  315  33 17   4.8   2.6
 15500  -6.7  19.9  320  32 17   4.2   2.3 |  -6.8  19.8  315  30 16   4.9   2.7
 15000  -6.1  21.0  320  30 15   4.1   2.3 |  -6.1  21.0  315  28 14   5.0   2.7
 14500  -5.4  22.3  320  28 14   5.1   2.8 |  -5.0  23.0  310  25 13   5.3   2.9
 14000  -4.5  23.9  320  26 13   5.9   3.3 |  -4.2  24.4  310  22 11   5.6   3.1
 13500  -3.6  25.5  325  25 13   6.3   3.4 |  -3.4  25.9  305  20 10   6.5   3.6
 13000  -2.6  27.3  325  23 12   6.8   3.7 |  -2.2  28.0  300  18  9   7.9   4.3
 12500  -1.6  29.1  325  21 11   6.8   3.8 |  -1.0  30.2  300  16  8   7.8   4.3
 12000  -0.5  31.1  325  20 10   6.9   3.8 |   0.1  32.2  295  15  8   7.5   4.1
 11500   0.5  32.9  320  18  9   7.0   3.8 |   1.2  34.2  290  14  7   7.0   3.8
 11000   1.5  34.7  320  16  8   7.2   4.0 |   2.0  35.6  290  12  6   5.5   3.0
 10500   2.6  36.7  315  14  7   6.7   3.7 |   2.8  37.0  290  11  5   4.6   2.5
 10250   3.0  37.4  315  13  7   5.7   3.1 |   3.1  37.6  285  10  5   3.0   1.6
 10000   3.5  38.3  315  13  7   7.4   4.0 |   3.4  38.1  285   9  5   4.9   2.7
  9750   4.1  39.4  315  12  6   9.2   5.0 |   3.8  38.8  285   7  4   6.6   3.6
  9500   4.7  40.5  315  10  5   6.8   3.7 |   4.3  39.7  280   5  3   5.0   2.7
  9250   5.1  41.2  315   9  5   4.6   2.5 |   4.6  40.3  280   4  2   3.3   1.8
  9000   5.5  41.9  320   8  4   5.3   2.9 |   4.9  40.8  275   3  1   5.0   2.7
  8750   5.9  42.6  320   7  3   5.7   3.1 |   5.4  41.7  255   1  1   6.9   3.8
  8500   6.3  43.3  330   5  3   5.4   3.0 |   5.9  42.6  150   1  0   7.7   4.2
  8250   6.7  44.1  340   3  2   5.3   2.9 |   6.5  43.7  120   2  1   8.1   4.4
  8000   7.0  44.6  015   2  1   5.1   2.8 |   7.1  44.8  110   3  2   8.5   4.7
  7750   7.4  45.3  075   2  1   6.8   3.7 |   7.7  45.9  105   4  2   9.7   5.3
  7500   8.0  46.4  085   3  1   9.5   5.2 |   8.5  47.3  100   4  2   9.8   5.4
  7250   8.8  47.8  085   3  1   9.8   5.4 |   9.2  48.6  095   5  2   9.5   5.2
  7000   9.5  49.1  085   3  1   9.8   5.4 |   9.9  49.8  090   5  3   9.6   5.2
  6750  10.2  50.4  085   3  1   9.9   5.4 |  10.6  51.1  085   5  3   9.6   5.3
  6500  11.0  51.8  085   3  1  10.0   5.5 |  11.3  52.3  085   6  3   9.7   5.3
  6250  11.7  53.1  085   3  1   9.7   5.3 |  12.1  53.8  080   6  3   9.7   5.3
  6000  12.5  54.5  085   3  1  10.9   6.0 |  12.8  55.0  080   6  3   9.6   5.3
  5750  13.4  56.1  085   3  1  14.7   8.1 |  13.4  56.1  075   6  3   6.5   3.6
  5500  14.6  58.3  085   3  1  17.3   9.5 |  13.7  56.7  075   5  2   1.9   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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