Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 231257
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0657 MDT Tuesday, September 23, 2014

This forecast is for Tuesday, September 23, 2014:

If the trigger temperature of 74.4 F/23.5 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1141 ft/min (5.8 m/s)
   Maximum height of thermals.................. 17517 ft MSL (12232 ft AGL)

Forecast maximum temperature................... 82.0 F/28.2 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 12709 ft MSL (7423 ft AGL)
Thermal soaring outlook for Wednesday 09/24.... Excellent

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 28000 ft MSL (22715 ft AGL)
Wave soaring outlook for Wednesday 09/24....... Poor

Remarks... Isolated showers

Sunrise/Sunset.................... 06:48:04 / 18:56:25 MDT
Total possible sunshine........... 12 hr 8 min 21 sec (728 min 21 sec)
Altitude of sun at 12:51:45 MDT... 49.98 degrees

Upper air data from rawinsonde observation taken on 09/23/2014 at 0600 MDT

Freezing level.................. 13764 ft MSL (8479 ft AGL)
Convective condensation level... 13900 ft MSL (8615 ft AGL)
Lifted condensation level....... 14910 ft MSL (9625 ft AGL)
Lifted index.................... -0.9
K index......................... +22.6

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  -65.7 -86.3   300   39   20   6.4   3.5   84.2 183.5    32.7      M    M
 45000  -58.7 -73.7   300   32   16   5.4   3.0   70.3 158.6    26.6      M    M
 40000  -49.1 -56.4   285   45   23   5.1   2.8   62.4 144.3    23.1      M    M
 38000  -46.0 -50.8   285   46   24   5.1   2.8   57.9 136.3    20.7      M    M
 36000  -42.9 -45.2   285   48   25   5.1   2.8   54.3 129.7    18.7      M    M
 34000  -41.1 -42.0   285   52   27   1.2   0.7   48.8 119.9    15.2      M    M
 32000  -37.7 -35.9   280   50   26   6.0   3.3   45.4 113.7    13.0      M    M
 30000  -34.0 -29.2   285   43   22   7.1   3.9   41.5 106.8    10.5      M    M
 29000  -31.9 -25.4   285   44   22   8.1   4.4   40.5 104.9     9.8      M    M
 28000  -29.2 -20.6   285   44   23   9.1   5.0   40.1 104.2     9.6      M    M
 27000  -26.5 -15.7   285   45   23   9.1   5.0   39.8 103.7     9.5      M    M
 26000  -23.7 -10.7   285   45   23   7.4   4.0   39.7 103.4     9.5      M    M
 25000  -22.1  -7.8   285   46   24   7.7   4.2   38.1 100.5     8.3      M    M
 24000  -19.4  -2.9   285   46   24   8.8   4.8   37.7  99.9     8.1      M    M
 23000  -16.7   1.9   285   45   23   8.8   4.8   37.3  99.1     7.8      M    M
 22000  -14.1   6.6   290   45   23   8.8   4.8   36.9  98.5     7.6      M    M
 21000  -11.5  11.3   290   44   23   8.8   4.8   36.7  98.0     7.5      M    M
 20000   -8.9  16.0   290   44   23   8.6   4.7   36.5  97.8     7.5      M    M
 19500   -7.5  18.5   290   40   21   6.3   3.4   36.3  97.4     7.4      M    M
 19000   -8.8  16.2   295   36   19 -10.2  -5.6   33.4  92.1     4.7      M    M
 18500   -9.3  15.3   300   28   14 -12.0  -6.6   31.3  88.3     2.7      M    M
 18000  -10.0  14.0   310   20   10  10.7   5.8   28.9  84.0     0.5      M    M
 17500   -9.0  15.8   305   21   11   6.7   3.7   28.4  83.2     0.1      M    M
 17000   -8.0  17.6   300   22   12   6.8   3.7   27.9  82.2    -0.4   1103  5.6
 16500   -6.8  19.8   300   24   13   8.7   4.8   27.6  81.7    -0.7   1053  5.3
 16000   -5.5  22.1   295   27   14   8.6   4.7   27.4  81.3    -0.8   1000  5.1
 15500   -4.3  24.3   295   28   14   8.7   4.8   27.2  81.0    -1.0    947  4.8
 15000   -2.7  27.1   295   29   15   6.6   3.6   26.5  79.8    -1.7    879  4.5
 14500   -1.6  29.1   295   30   16   8.3   4.6   26.3  79.3    -2.0    828  4.2
 14000   -0.3  31.5   295   31   16   8.4   4.6   26.1  78.9    -2.2    777  3.9
 13500    0.9  33.6   285   33   17   8.3   4.6   25.8  78.5    -2.5    725  3.7
 13000    2.1  35.8   280   33   17   7.4   4.1   25.6  78.1    -2.7    674  3.4
 12500    2.9  37.2   275   25   13   6.3   3.5   25.0  77.1    -3.4    634  3.2
 12000    4.2  39.6   270   19   10  10.0   5.5   24.8  76.7    -3.6    583  3.0
 11500    5.6  42.1   265   18    9   9.7   5.3   24.8  76.6    -3.7    525  2.7
 11000    7.1  44.8   265   17    9   9.7   5.3   24.8  76.6    -3.7    467  2.4
 10500    8.5  47.3   260   16    8   9.5   5.2   24.8  76.6    -3.7    409  2.1
 10250    9.2  48.6   260   16    8   9.1   5.0   24.8  76.6    -3.8    381  1.9
 10000    9.9  49.8   260   16    8   9.0   4.9   24.7  76.5    -3.9    353  1.8
  9750   10.5  50.9   265   15    8   9.0   4.9   24.7  76.4    -3.9    326  1.7
  9500   11.2  52.2   265   15    8   9.0   5.0   24.6  76.3    -4.0    299  1.5
  9250   11.8  53.2   270   14    7   8.9   4.9   24.5  76.2    -4.1    272  1.4
  9000   12.5  54.5   275   14    7   8.3   4.5   24.5  76.0    -4.2    245  1.2
  8750   13.1  55.6   275   11    6   8.0   4.4   24.3  75.8    -4.3    220  1.1
  8500   13.7  56.7   270    8    4   8.1   4.4   24.2  75.6    -4.5    195  1.0
  8250   14.2  57.6   265    5    3   8.1   4.4   24.1  75.4    -4.6    170  0.9
  8000   14.8  58.6   250    3    2   8.1   4.4   24.0  75.1    -4.8    145  0.7
  7750   15.4  59.7   250    4    2   8.1   4.4   23.8  74.9    -4.9    120  0.6
  7500   16.0  60.8   255    4    2   8.1   4.5   23.7  74.7    -5.1     95  0.5
  7250   16.6  61.9   255    4    2   7.9   4.3   23.6  74.4    -5.2     69  0.4
  7000   17.2  63.0   255    5    3   8.7   4.8   23.5  74.2    -5.4     44  0.2
  6750   17.8  64.0   235    7    4   5.7   3.1   23.3  74.0    -5.5     19  0.1
  6500   17.9  64.2   220    9    5   0.1   0.0   22.8  73.0    -6.1      8  0.0
  6250   17.6  63.7   215   12    6  -8.5  -4.7   21.8  71.2    -7.2      9  0.0
  6000   16.7  62.1   210   15    8  -8.9  -4.9   20.2  68.4    -8.8     28  0.1
  5750   16.5  61.7   210   10    5   2.9   1.6   19.3  66.7    -9.8     29  0.1
  5500   16.6  61.9   210    5    3  -2.1  -1.1   18.8  65.8   -10.5     19  0.1

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

           09/23/2014 at 0900 MDT          |       09/23/2014 at 1200 MDT
                                           |
K index... +19.4  LI... -0.5               | K index... +16.8  LI... -0.8
CAPE... +20.0  CIN... -78.2                | CAPE... +128.4  CIN... -42.4
                                           |
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 -63.5 -82.3  310  17  9   2.8   1.5 | -63.9 -83.0  295  16  8   3.5   1.9
 45000 -57.9 -72.2  310  33 17   5.4   3.0 | -57.6 -71.7  305  27 14   5.2   2.9
 40000 -49.8 -57.6  295  42 21   5.3   2.9 | -49.7 -57.5  305  35 18   5.9   3.3
 38000 -46.6 -51.9  290  42 22   5.3   2.9 | -46.2 -51.2  300  37 19   5.9   3.3
 36000 -43.4 -46.1  290  42 22   5.3   2.9 | -42.6 -44.7  295  39 20   5.8   3.2
 34000 -40.8 -41.4  285  42 22   3.9   2.1 | -40.2 -40.4  290  38 20   3.3   1.8
 32000 -38.5 -37.3  285  41 21   3.9   2.1 | -38.3 -36.9  285  36 19   3.3   1.8
 30000 -33.7 -28.7  285  40 21   8.6   4.7 | -33.9 -29.0  285  35 18   7.9   4.3
 29000 -31.1 -24.0  285  40 20   8.6   4.7 | -31.5 -24.7  285  34 18   7.9   4.3
 28000 -28.5 -19.3  290  39 20   8.2   4.5 | -29.2 -20.6  285  34 17   7.9   4.3
 27000 -26.2 -15.2  290  39 20   7.7   4.2 | -26.8 -16.2  285  34 18   7.9   4.4
 26000 -23.8 -10.8  290  39 20   7.7   4.2 | -24.4 -11.9  290  34 18   7.9   4.4
 25000 -21.5  -6.7  285  39 20   7.8   4.3 | -22.0  -7.6  290  35 18   7.9   4.3
 24000 -19.3  -2.7  285  37 19   7.4   4.0 | -19.6  -3.3  290  34 17   8.1   4.5
 23000 -17.1   1.2  285  34 17   7.4   4.1 | -17.2   1.0  290  32 17   8.1   4.5
 22000 -14.9   5.2  280  31 16   7.4   4.1 | -14.7   5.5  290  31 16   8.1   4.4
 21000 -13.2   8.2  280  28 14   5.5   3.0 | -12.9   8.8  280  28 14   5.9   3.2
 20000 -11.6  11.1  275  25 13   5.6   3.1 | -11.1  12.0  275  25 13   6.0   3.3
 19500 -10.8  12.6  270  23 12   5.7   3.1 | -10.2  13.6  270  24 12   6.1   3.3
 19000 -10.0  14.0  270  22 11   6.0   3.3 |  -9.4  15.1  265  22 12   5.1   2.8
 18500  -9.1  15.6  270  21 11   6.1   3.3 |  -8.7  16.3  265  21 11   4.9   2.7
 18000  -8.2  17.2  270  19 10   6.2   3.4 |  -8.0  17.6  265  20 10   5.1   2.8
 17500  -7.3  18.9  275  18  9   6.6   3.6 |  -7.2  19.0  265  19 10   6.4   3.5
 17000  -6.3  20.7  275  17  9   6.6   3.6 |  -6.2  20.8  265  18  9   6.2   3.4
 16500  -5.3  22.5  280  17  9   7.3   4.0 |  -5.2  22.6  270  17  9   7.9   4.3
 16000  -4.3  24.3  285  17  9   7.4   4.1 |  -4.1  24.6  275  16  8   8.0   4.4
 15500  -3.2  26.2  290  17  9   7.5   4.1 |  -2.9  26.8  285  15  8   7.9   4.3
 15000  -1.5  29.3  300  18  9   7.6   4.2 |  -1.2  29.8  295  16  8   7.7   4.2
 14500  -0.4  31.3  300  20 10   7.6   4.2 |  -0.0  32.0  305  18  9   7.6   4.2
 14000   0.8  33.4  300  22 11   7.7   4.2 |   1.1  34.0  305  19 10   7.6   4.2
 13500   1.9  35.4  305  23 12   7.5   4.1 |   2.2  36.0  310  21 11   7.4   4.1
 13000   3.0  37.4  305  25 13   7.4   4.1 |   3.3  37.9  310  24 12   7.3   4.0
 12500   4.1  39.4  305  27 14   7.3   4.0 |   4.3  39.7  305  26 13   7.0   3.9
 12000   5.1  41.2  305  27 14   7.0   3.8 |   5.3  41.5  305  26 13   6.7   3.7
 11500   6.1  43.0  305  27 14   7.2   3.9 |   6.2  43.2  305  26 13   6.9   3.8
 11000   7.1  44.8  305  27 14   7.3   4.0 |   7.2  45.0  305  24 13   7.3   4.0
 10500   8.2  46.8  305  26 13   4.2   2.3 |   8.2  46.8  305  23 12   4.6   2.5
 10250   8.4  47.1  305  26 13   4.1   2.2 |   8.4  47.1  305  23 12   4.4   2.4
 10000   8.9  48.0  305  25 13   9.5   5.2 |   8.9  48.0  305  21 11   8.6   4.7
  9750   9.5  49.1  305  25 13  10.1   5.5 |   9.5  49.1  300  19 10   8.7   4.8
  9500  10.2  50.4  300  24 12   8.1   4.4 |  10.0  50.0  300  18  9   7.6   4.2
  9250  10.6  51.1  300  23 12   5.4   3.0 |  10.5  50.9  295  16  8   6.2   3.4
  9000  11.1  52.0  300  22 11   7.5   4.1 |  11.0  51.8  295  14  7   8.7   4.8
  8750  11.7  53.1  300  21 11   9.1   5.0 |  11.7  53.1  285  12  6  10.5   5.8
  8500  12.3  54.1  295  20 10   8.2   4.5 |  12.4  54.3  280  10  5   9.7   5.3
  8250  12.8  55.0  295  19 10   7.6   4.2 |  13.1  55.6  280  10  5   9.4   5.2
  8000  13.4  56.1  290  18  9   8.2   4.5 |  13.8  56.8  280   9  5   9.9   5.4
  7750  14.0  57.2  290  17  9   9.0   4.9 |  14.6  58.3  275   9  5  10.4   5.7
  7500  14.7  58.5  285  16  8   9.1   5.0 |  15.3  59.5  275   9  5  10.3   5.6
  7250  15.4  59.7  285  15  8   9.1   5.0 |  16.1  61.0  275   9  5  10.1   5.5
  7000  16.0  60.8  280  14  7   9.1   5.0 |  16.8  62.2  275   9  5  10.4   5.7
  6750  16.7  62.1  275  13  7   8.5   4.7 |  17.6  63.7  275   9  5  10.3   5.7
  6500  17.3  63.1  270  12  6   7.4   4.1 |  18.4  65.1  275   9  4  10.0   5.5
  6250  17.9  64.2  265  12  6   9.3   5.1 |  19.1  66.4  275   8  4   9.5   5.2
  6000  18.5  65.3  260  11  6   2.4   1.3 |  19.8  67.6  275   8  4  11.2   6.2
  5750  18.2  64.8  250   9  5  -4.5  -2.5 |  20.9  69.6  275   8  4  16.3   9.0
  5500  18.1  64.6  240   8  4   4.5   2.4 |  22.2  72.0  275   8  4  19.6  10.8

           09/23/2014 at 1500 MDT          |       09/23/2014 at 1800 MDT
                                           |
K index... +25.9  LI... -0.8               | K index... +26.0  LI... -1.7
CAPE... +204.8  CIN... -24.0               | CAPE... +277.4  CIN... -29.0
                                           |
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 -64.2 -83.6  295  19 10   3.2   1.8 | -64.0 -83.2  295  18  9   2.9   1.6
 45000 -57.8 -72.0  305  28 14   6.1   3.3 | -57.9 -72.2  300  26 13   6.2   3.4
 40000 -48.8 -55.8  305  34 18   5.2   2.9 | -48.8 -55.8  310  33 17   4.2   2.3
 38000 -45.6 -50.1  305  36 18   5.2   2.9 | -46.3 -51.3  310  34 17   4.2   2.3
 36000 -42.5 -44.5  300  37 19   5.2   2.8 | -43.7 -46.7  315  34 17   4.2   2.3
 34000 -40.1 -40.2  300  37 19   3.6   2.0 | -41.2 -42.2  315  32 17   4.3   2.4
 32000 -37.9 -36.2  305  36 18   3.7   2.0 | -38.6 -37.5  320  30 16   4.4   2.4
 30000 -33.9 -29.0  300  34 18   6.8   3.7 | -33.8 -28.8  320  28 15   8.1   4.5
 29000 -31.9 -25.4  300  34 17   6.8   3.7 | -31.4 -24.5  315  27 14   8.2   4.5
 28000 -29.8 -21.6  300  33 17   7.9   4.3 | -29.0 -20.2  315  27 14   7.9   4.4
 27000 -27.1 -16.8  300  33 17   9.1   5.0 | -26.7 -16.1  315  26 13   7.7   4.2
 26000 -24.4 -11.9  300  32 16   9.1   5.0 | -24.4 -11.9  320  25 13   7.8   4.3
 25000 -21.7  -7.1  300  31 16   9.3   5.1 | -22.1  -7.8  320  24 13   7.8   4.3
 24000 -19.3  -2.7  300  31 16   7.7   4.2 | -19.8  -3.6  320  25 13   7.5   4.1
 23000 -17.0   1.4  295  31 16   7.7   4.2 | -17.6   0.3  315  25 13   7.5   4.1
 22000 -14.7   5.5  295  31 16   7.6   4.2 | -15.4   4.3  310  26 13   7.4   4.1
 21000 -12.7   9.1  290  29 15   6.5   3.6 | -13.4   7.9  305  25 13   6.6   3.6
 20000 -10.8  12.6  280  27 14   6.6   3.6 | -11.4  11.5  300  23 12   6.6   3.6
 19500  -9.8  14.4  280  26 14   6.7   3.7 | -10.5  13.1  300  23 12   6.6   3.6
 19000  -9.0  15.8  275  25 13   4.7   2.6 |  -9.5  14.9  295  22 11   6.7   3.6
 18500  -8.4  16.9  275  23 12   4.6   2.5 |  -8.5  16.7  295  21 11   6.7   3.7
 18000  -7.8  18.0  275  20 10   5.0   2.7 |  -7.6  18.3  295  19 10   7.0   3.8
 17500  -7.1  19.2  285  18  9   5.8   3.2 |  -6.5  20.3  300  19 10   7.9   4.3
 17000  -6.3  20.7  290  16  8   5.6   3.1 |  -5.3  22.5  310  20 10   8.0   4.4
 16500  -5.3  22.5  300  15  8   8.3   4.5 |  -4.3  24.3  310  21 11   6.8   3.7
 16000  -4.1  24.6  305  16  8   8.5   4.7 |  -3.3  26.1  310  22 11   6.8   3.7
 15500  -2.8  27.0  315  16  8   8.4   4.6 |  -2.3  27.9  310  23 12   6.9   3.8
 15000  -0.9  30.4  310  20 10   8.4   4.6 |  -0.7  30.7  305  21 11   7.1   3.9
 14500   0.3  32.5  310  22 11   7.5   4.1 |   0.4  32.7  305  21 11   7.9   4.3
 14000   1.4  34.5  305  24 12   7.2   4.0 |   1.5  34.7  300  21 11   8.1   4.4
 13500   2.5  36.5  305  26 13   6.9   3.8 |   2.7  36.9  295  22 11   8.0   4.4
 13000   3.4  38.1  300  26 13   6.7   3.7 |   3.8  38.8  295  22 11   8.0   4.4
 12500   4.3  39.7  295  26 13   7.2   3.9 |   4.9  40.8  290  22 11   8.3   4.5
 12000   5.4  41.7  295  24 12   8.0   4.4 |   6.2  43.2  295  21 11   8.7   4.8
 11500   6.5  43.7  290  22 11   8.1   4.5 |   7.4  45.3  295  19 10   8.8   4.8
 11000   7.7  45.9  290  19 10   8.1   4.4 |   8.7  47.7  300  18  9   8.8   4.8
 10500   8.9  48.0  290  15  8   4.1   2.3 |  10.1  50.2  300  17  9   4.0   2.2
 10250   9.1  48.4  290  15  8   5.6   3.1 |  10.2  50.4  300  17  9   5.1   2.8
 10000   9.8  49.6  290  13  7  12.1   6.6 |  10.9  51.6  300  16  8  12.1   6.6
  9750  10.6  51.1  285  11  6  10.7   5.9 |  11.7  53.1  305  15  7  10.8   5.9
  9500  11.4  52.5  285  10  5   9.9   5.4 |  12.5  54.5  305  13  7   9.0   4.9
  9250  12.0  53.6  285   9  5   8.5   4.6 |  13.0  55.4  310  12  6   6.5   3.6
  9000  12.7  54.9  285   9  5  10.0   5.5 |  13.6  56.5  310  11  5   8.8   4.9
  8750  13.5  56.3  285   9  5  10.9   6.0 |  14.3  57.7  310   9  5  10.1   5.6
  8500  14.3  57.7  285   9  5  10.4   5.7 |  15.0  59.0  315   7  4   9.2   5.0
  8250  15.1  59.2  285   9  4  10.3   5.6 |  15.7  60.3  315   7  3   8.3   4.6
  8000  15.8  60.4  285   9  4  10.1   5.5 |  16.3  61.3  315   6  3   9.2   5.1
  7750  16.6  61.9  285   8  4   9.8   5.4 |  17.0  62.6  315   6  3  10.1   5.5
  7500  17.3  63.1  285   8  4  10.1   5.6 |  17.7  63.9  320   5  3  10.1   5.5
  7250  18.1  64.6  285   8  4  10.5   5.7 |  18.5  65.3  320   5  3  10.3   5.6
  7000  18.8  65.8  285   8  4  10.0   5.5 |  19.3  66.7  320   5  3  10.0   5.5
  6750  19.6  67.3  285   8  4   9.8   5.4 |  20.0  68.0  320   5  3   9.8   5.4
  6500  20.3  68.5  285   8  4  10.3   5.6 |  20.7  69.3  320   5  3   9.9   5.4
  6250  21.1  70.0  285   8  4  11.0   6.0 |  21.5  70.7  325   5  2  10.4   5.7
  6000  21.9  71.4  285   7  4   9.2   5.0 |  22.2  72.0  325   5  2   8.9   4.9
  5750  22.6  72.7  285   7  4  13.1   7.2 |  22.9  73.2  325   5  2   8.4   4.6
  5500  24.0  75.2  285   7  4  24.6  13.5 |  23.5  74.3  325   4  2  11.9   6.5
________________________________________________________________________________

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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