Soaring Guidance
Issued by NWS Denver/Boulder, CO

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Soaring Forecast
National Weather Service Denver/Boulder, Colorado
2111 MDT Monday, October 23, 2017

This forecast is for Tuesday, October 24, 2017:

If the trigger temperature of 49.7 F/9.8 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 478 ft/min (2.4 m/s)
   Maximum height of thermals.................. 12377 ft MSL (7012 ft AGL)

Forecast maximum temperature................... 60.0 F/16.0 C
Time of trigger temperature.................... 1100 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................. 11041 ft MSL (5677 ft AGL)
Thermal soaring outlook for Wednesday 10/25.... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 12749 ft MSL (7384 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak NVA
Potential height of wave....................... 45732 ft MSL (40367 ft AGL)
Wave soaring outlook for Wednesday 10/25....... Poor

Remarks...

Sunrise/Sunset.................... 07:19:53 / 18:07:16 MDT
Total possible sunshine........... 10 hr 47 min 23 sec (647 min 23 sec)
Altitude of sun at 12:43:35 MDT... 38.08 degrees

Upper air data from numerical model forecast valid on 10/24/2017 at 0600 MDT

Freezing level.................. 8148 ft MSL (2783 ft AGL)
Convective condensation level... 21064 ft MSL (15699 ft AGL)
Lifted condensation level....... 14722 ft MSL (9357 ft AGL)
Lifted index.................... +13.0
K index......................... -12.0

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  -65.9 -86.6   340   33   17  -2.3  -1.2      M     M       M      M    M
 45000  -67.7 -89.9   340   43   22   5.0   2.8      M     M       M      M    M
 40000  -60.2 -76.4   340   44   22   6.2   3.4      M     M       M      M    M
 38000  -55.2 -67.4   340   42   22   8.4   4.6      M     M       M      M    M
 36000  -49.6 -57.3   340   40   21   8.4   4.6      M     M       M      M    M
 34000  -44.6 -48.3   335   39   20   8.3   4.5      M     M       M      M    M
 32000  -39.6 -39.3   335   37   19   8.3   4.5      M     M       M      M    M
 30000  -34.6 -30.3   335   36   18   8.4   4.6   42.6 108.6    20.4      M    M
 29000  -32.1 -25.8   335   35   18   8.4   4.6   42.0 107.6    20.2      M    M
 28000  -29.6 -21.3   335   35   18   8.5   4.7   41.6 106.9    20.1      M    M
 27000  -27.3 -17.1   335   34   18   7.4   4.1   40.7 105.3    19.7      M    M
 26000  -25.1 -13.2   335   34   17   7.4   4.1   39.8 103.7    19.2      M    M
 25000  -22.9  -9.2   335   33   17   7.4   4.1   39.0 102.3    18.8      M    M
 24000  -20.8  -5.4   340   32   17   6.1   3.3   37.9 100.2    18.1      M    M
 23000  -19.0  -2.2   340   31   16   6.0   3.3   36.5  97.7    17.1      M    M
 22000  -17.2   1.0   340   30   16   6.0   3.3   35.2  95.4    16.2      M    M
 21000  -15.5   4.1   340   30   15   5.9   3.3   33.8  92.9    15.3      M    M
 20000  -13.2   8.2   340   29   15   5.9   3.3   32.1  89.8    14.0      M    M
 19500  -12.3   9.9   340   29   15   6.0   3.3   31.5  88.7    13.6      M    M
 19000  -11.5  11.3   340   28   15   5.5   3.0   30.8  87.5    13.1      M    M
 18500  -10.7  12.7   340   28   14   5.5   3.0   30.1  86.2    12.5      M    M
 18000   -9.8  14.4   340   28   14   5.2   2.9   29.4  84.9    11.9      M    M
 17500   -9.1  15.6   340   28   14   4.6   2.5   28.5  83.3    11.2      M    M
 17000   -8.5  16.7   340   27   14   4.7   2.6   27.6  81.7    10.5      M    M
 16500   -7.9  17.8   340   27   14   3.3   1.8   26.7  80.0     9.7      M    M
 16000   -7.3  18.9   340   26   14   3.4   1.9   25.6  78.0     8.8      M    M
 15500   -6.9  19.6   340   26   13   2.4   1.3   24.5  76.1     7.9      M    M
 15000   -6.6  20.1   340   25   13   1.9   1.1   23.2  73.7     6.7      M    M
 14500   -6.3  20.7   335   25   13   1.6   0.9   21.9  71.4     5.6      M    M
 14000   -6.1  21.0   335   24   12   1.0   0.6   20.4  68.8     4.3      M    M
 13500   -5.9  21.4   335   23   12   0.9   0.5   19.0  66.2     3.0      M    M
 13000   -5.8  21.6   335   22   11   0.7   0.4   17.5  63.6     1.7      M    M
 12500   -5.8  21.6   335   21   11   1.0   0.5   16.1  60.9     0.3      M    M
 12000   -5.5  22.1   335   19   10   2.1   1.2   14.8  58.6    -0.9    462  2.3
 11500   -5.3  22.5   330   17    9   2.7   1.5   13.5  56.4    -2.1    439  2.2
 11000   -4.7  23.5   330   15    8   4.9   2.7   12.6  54.7    -3.0    407  2.1
 10500   -4.0  24.8   325   12    6   5.4   3.0   11.8  53.3    -3.8    373  1.9
 10250   -3.6  25.5   325   11    6   6.6   3.6   11.6  52.8    -4.1    352  1.8
 10000   -3.1  26.4   325   10    5   6.1   3.4   11.3  52.3    -4.4    331  1.7
  9750   -2.8  27.0   325    9    5   4.6   2.5   11.0  51.7    -4.8    312  1.6
  9500   -2.4  27.7   320    9    4   4.8   2.6   10.5  51.0    -5.2    295  1.5
  9250   -2.0  28.4   320    8    4   5.6   3.0   10.2  50.3    -5.6    276  1.4
  9000   -1.6  29.1   325    7    4   5.3   2.9    9.8  49.7    -5.9    257  1.3
  8750   -1.2  29.8   325    7    3   6.4   3.5    9.5  49.2    -6.2    237  1.2
  8500   -0.7  30.7   325    6    3   6.4   3.5    9.3  48.7    -6.5    215  1.1
  8250   -0.3  31.5   330    6    3   5.7   3.1    9.0  48.2    -6.8    194  1.0
  8000    0.1  32.2   335    5    3   6.1   3.3    8.7  47.6    -7.1    174  0.9
  7750    0.6  33.1   340    5    2   5.2   2.9    8.4  47.1    -7.4    153  0.8
  7500    0.9  33.6   345    5    2   4.8   2.6    8.0  46.4    -7.8    135  0.7
  7250    1.3  34.3   355    4    2   5.3   2.9    7.6  45.8    -8.2    116  0.6
  7000    1.7  35.1   360    4    2   5.3   2.9    7.3  45.1    -8.6     97  0.5
  6750    2.1  35.8   010    4    2   4.9   2.7    7.0  44.5    -8.9     78  0.4
  6500    2.5  36.5   015    3    1   4.3   2.4    6.6  43.8    -9.3     60  0.3
  6250    2.8  37.0   020    2    1   4.5   2.5    6.2  43.1    -9.7     43  0.2
  6000    3.2  37.8   040    1    0   6.1   3.4    5.8  42.5   -10.1     24  0.1
  5750    3.7  38.7   160    1    0   7.7   4.2    5.6  42.1   -10.3      0  0.0
  5500    4.1  39.4   175    1    1   2.3   1.3    5.3  41.6   -10.7      M    M

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

           10/24/2017 at 0900 MDT          |       10/24/2017 at 1200 MDT
                                           |
CAPE...     0.0    LI...      +12.8        | CAPE...     0.0    LI...      +11.6
CINH...     0.0    K Index... -10.1        | CINH...     0.0    K Index...  -5.9
                                           |
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 -66.3 -87.3  340  30 16  -1.7  -0.9 | -66.5 -87.7  340  29 15  -1.3  -0.7
 45000 -67.1 -88.8  345  39 20   5.6   3.1 | -67.0 -88.6  340  36 18   5.5   3.0
 40000 -58.8 -73.8  350  40 21   6.5   3.5 | -58.3 -72.9  350  38 19   7.5   4.1
 38000 -53.5 -64.3  350  40 21   7.8   4.3 | -53.7 -64.7  350  38 20   7.7   4.2
 36000 -48.9 -56.0  350  40 21   7.8   4.3 | -49.1 -56.4  355  38 20   7.7   4.2
 34000 -44.1 -47.4  345  38 20   7.9   4.3 | -44.4 -47.9  355  37 19   8.1   4.5
 32000 -39.4 -38.9  345  36 18   7.9   4.3 | -39.5 -39.1  355  34 18   8.1   4.5
 30000 -34.5 -30.1  340  33 17   8.2   4.5 | -34.0 -29.2  350  32 17   8.3   4.5
 29000 -32.0 -25.6  340  32 17   8.2   4.5 | -31.5 -24.7  350  31 16   8.3   4.5
 28000 -29.6 -21.3  340  31 16   8.3   4.6 | -29.0 -20.2  345  31 16   8.1   4.4
 27000 -27.3 -17.1  340  31 16   7.3   4.0 | -26.8 -16.2  345  30 16   7.3   4.0
 26000 -25.1 -13.2  340  30 16   7.3   4.0 | -24.6 -12.3  345  30 15   7.3   4.0
 25000 -22.9  -9.2  340  30 15   7.3   4.0 | -22.5  -8.5  345  29 15   7.4   4.1
 24000 -20.9  -5.6  340  29 15   6.1   3.4 | -20.6  -5.1  345  28 14   5.8   3.2
 23000 -19.1  -2.4  340  28 15   6.1   3.3 | -18.8  -1.8  345  27 14   5.8   3.2
 22000 -17.3   0.9  340  27 14   6.1   3.4 | -17.1   1.2  345  26 13   5.9   3.2
 21000 -15.2   4.6  345  27 14   5.5   3.0 | -15.5   4.1  345  25 13   5.3   2.9
 20000 -13.5   7.7  345  26 14   5.5   3.0 | -13.9   7.0  345  24 12   5.4   2.9
 19500 -12.7   9.1  345  26 13   5.6   3.1 | -13.1   8.4  345  24 12   5.4   2.9
 19000 -11.9  10.6  345  26 13   4.9   2.7 | -12.3   9.9  345  23 12   5.2   2.9
 18500 -11.2  11.8  345  26 13   5.0   2.7 | -11.6  11.1  350  23 12   5.1   2.8
 18000 -10.4  13.3  345  26 13   4.9   2.7 | -10.8  12.6  350  23 12   5.1   2.8
 17500  -9.7  14.5  345  26 13   4.7   2.6 | -10.1  13.8  350  23 12   5.0   2.7
 17000  -9.0  15.8  345  26 13   4.7   2.6 |  -9.3  15.3  350  23 12   5.0   2.8
 16500  -8.4  16.9  345  26 13   4.0   2.2 |  -8.3  17.1  350  22 11   4.3   2.4
 16000  -7.8  18.0  345  26 13   4.0   2.2 |  -7.6  18.3  350  22 11   4.4   2.4
 15500  -7.2  19.0  345  26 13   3.9   2.2 |  -7.0  19.4  350  22 11   4.4   2.4
 15000  -6.6  20.1  345  25 13   3.9   2.1 |  -6.3  20.7  350  22 11   4.4   2.4
 14500  -6.0  21.2  345  25 13   3.3   1.8 |  -5.7  21.7  350  22 11   4.1   2.3
 14000  -5.6  21.9  345  25 13   2.8   1.6 |  -5.1  22.8  350  22 11   4.1   2.2
 13500  -5.2  22.6  345  24 12   2.7   1.5 |  -4.5  23.9  350  21 11   3.9   2.1
 13000  -4.8  23.4  345  23 12   2.5   1.4 |  -3.9  25.0  350  21 11   3.7   2.0
 12500  -4.4  24.1  345  22 12   2.5   1.4 |  -3.4  25.9  345  21 11   3.7   2.0
 12000  -4.1  24.6  345  21 11   2.6   1.4 |  -2.9  26.8  345  20 10   3.6   2.0
 11500  -3.7  25.3  340  20 10   3.2   1.7 |  -2.3  27.9  345  20 10   4.4   2.4
 11000  -3.1  26.4  340  19 10   4.4   2.4 |  -1.6  29.1  340  18  9   5.1   2.8
 10500  -2.5  27.5  340  17  9   5.6   3.1 |  -0.8  30.6  340  17  9   6.5   3.6
 10250  -2.0  28.4  340  16  8   7.6   4.2 |  -0.2  31.6  340  16  8   8.2   4.5
 10000  -1.4  29.5  340  15  8   6.1   3.4 |   0.3  32.5  335  16  8   6.7   3.7
  9750  -1.1  30.0  340  14  7   3.7   2.0 |   0.8  33.4  335  14  7   5.4   3.0
  9500  -0.8  30.6  340  13  7   4.7   2.6 |   1.2  34.2  335  13  7   6.2   3.4
  9250  -0.4  31.3  340  12  6   6.3   3.5 |   1.6  34.9  335  13  7   6.4   3.5
  9000   0.0  32.0  340  11  6   5.9   3.2 |   2.1  35.8  335  12  6   6.8   3.7
  8750   0.5  32.9  340  10  5   5.8   3.2 |   2.6  36.7  335  11  5   6.9   3.8
  8500   0.9  33.6  335   9  4   5.8   3.2 |   3.1  37.6  335   9  5   6.1   3.4
  8250   1.3  34.3  335   8  4   5.7   3.1 |   3.5  38.3  335   8  4   5.9   3.3
  8000   1.8  35.2  335   7  3   6.5   3.6 |   4.0  39.2  335   7  4   5.8   3.2
  7750   2.2  36.0  335   6  3   5.8   3.2 |   4.4  39.9  340   6  3   5.8   3.2
  7500   2.6  36.7  335   5  2   4.2   2.3 |   4.8  40.6  340   5  3   5.9   3.3
  7250   2.9  37.2  335   4  2   4.5   2.4 |   5.3  41.5  340   4  2   5.9   3.3
  7000   3.2  37.8  330   3  2   4.1   2.3 |   5.7  42.3  345   3  2   5.9   3.2
  6750   3.5  38.3  335   2  1   3.3   1.8 |   6.2  43.2  350   2  1   7.7   4.2
  6500   3.7  38.7  325   1  1   2.8   1.6 |   6.8  44.2  355   2  1   9.2   5.0
  6250   3.9  39.0  285   1  0   3.1   1.7 |   7.5  45.5  005   1  1   8.7   4.8
  6000   4.2  39.6  210   1  0   2.8   1.5 |   8.1  46.6  010   1  1   8.5   4.6
  5750   4.4  39.9  185   2  1   4.7   2.6 |   8.7  47.7  015   1  0   8.2   4.5
  5500   4.9  40.8  185   2  1   8.9   4.9 |   9.5  49.1  020   1  0  14.0   7.7

           10/24/2017 at 1500 MDT          |       10/24/2017 at 1800 MDT
                                           |
CAPE...     0.0    LI...      +10.2        | CAPE...     0.0    LI...       +9.4
CINH...     0.0    K Index...  -5.1        | CINH...    -0.2    K Index...  -2.0
                                           |
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 -67.1 -88.8  340  28 14  -1.6  -0.9 | -66.5 -87.7  345  24 12  -1.5  -0.8
 45000 -67.7 -89.9  335  33 17   5.6   3.1 | -67.0 -88.6  340  28 14   5.1   2.8
 40000 -59.3 -74.7  350  34 18   6.8   3.7 | -59.3 -74.7  345  33 17   6.6   3.6
 38000 -54.0 -65.2  350  34 18   7.8   4.3 | -54.1 -65.4  345  31 16   7.7   4.2
 36000 -49.4 -56.9  350  34 18   7.8   4.3 | -49.5 -57.1  345  29 15   7.7   4.2
 34000 -44.4 -47.9  350  32 17   8.3   4.6 | -44.6 -48.3  345  27 14   8.2   4.5
 32000 -39.4 -38.9  355  31 16   8.3   4.6 | -39.7 -39.5  345  25 13   8.2   4.5
 30000 -34.4 -29.9  355  29 15   8.4   4.6 | -34.5 -30.1  350  24 12   8.7   4.8
 29000 -31.9 -25.4  350  29 15   8.4   4.6 | -31.9 -25.4  350  23 12   8.7   4.8
 28000 -29.4 -20.9  350  28 14   8.4   4.6 | -29.3 -20.7  350  23 12   8.7   4.8
 27000 -27.0 -16.6  350  27 14   7.8   4.3 | -26.8 -16.2  355  23 12   8.4   4.6
 26000 -24.6 -12.3  350  26 14   7.9   4.3 | -24.2 -11.6  355  23 12   8.4   4.6
 25000 -22.3  -8.1  355  26 13   7.9   4.3 | -21.7  -7.1  360  23 12   8.5   4.7
 24000 -20.3  -4.5  355  25 13   6.0   3.3 | -19.6  -3.3  005  22 11   6.3   3.5
 23000 -18.5  -1.3  350  24 12   6.0   3.3 | -17.7   0.1  005  21 11   6.3   3.4
 22000 -16.7   1.9  350  23 12   6.0   3.3 | -15.8   3.6  005  20 10   6.4   3.5
 21000 -15.0   5.0  350  22 11   5.7   3.1 | -13.8   7.2  005  19 10   5.3   2.9
 20000 -12.8   9.0  350  20 10   5.7   3.2 | -12.2  10.0  360  18  9   5.3   2.9
 19500 -12.0  10.4  350  20 10   5.7   3.1 | -11.4  11.5  360  18  9   5.3   2.9
 19000 -11.1  12.0  350  19 10   5.8   3.2 | -10.6  12.9  360  17  9   5.5   3.0
 18500 -10.2  13.6  350  19 10   5.8   3.2 |  -9.8  14.4  360  17  9   5.5   3.0
 18000  -9.4  15.1  350  19 10   5.4   3.0 |  -9.0  15.8  360  16  8   5.4   2.9
 17500  -8.6  16.5  350  18  9   5.1   2.8 |  -8.2  17.2  360  16  8   5.2   2.9
 17000  -7.9  17.8  350  18  9   5.1   2.8 |  -7.4  18.7  360  15  8   5.2   2.9
 16500  -7.2  19.0  350  18  9   4.2   2.3 |  -6.7  19.9  360  15  8   4.4   2.4
 16000  -6.5  20.3  350  17  9   4.3   2.3 |  -6.0  21.2  355  15  8   4.6   2.5
 15500  -5.9  21.4  350  17  9   4.0   2.2 |  -5.4  22.3  350  15  8   3.4   1.8
 15000  -5.3  22.5  350  17  9   4.0   2.2 |  -5.0  23.0  350  15  8   3.3   1.8
 14500  -4.8  23.4  350  17  9   4.2   2.3 |  -4.5  23.9  345  15  8   3.5   1.9
 14000  -4.1  24.6  350  18  9   4.3   2.3 |  -3.9  25.0  345  15  8   3.7   2.0
 13500  -3.5  25.7  350  18  9   4.1   2.2 |  -3.4  25.9  340  15  8   3.9   2.1
 13000  -3.0  26.6  345  18  9   3.8   2.1 |  -2.8  27.0  340  14  7   4.1   2.3
 12500  -2.4  27.7  340  18  9   4.0   2.2 |  -2.2  28.0  335  14  7   4.7   2.6
 12000  -1.8  28.8  340  17  9   4.6   2.5 |  -1.4  29.5  335  13  7   5.9   3.2
 11500  -1.1  30.0  335  16  8   5.4   3.0 |  -0.6  30.9  330  13  7   6.8   3.8
 11000  -0.1  31.8  335  16  8   7.1   3.9 |   0.7  33.3  330  12  6   8.7   4.8
 10500   1.0  33.8  330  15  8   7.4   4.1 |   2.0  35.6  330  12  6   8.5   4.7
 10250   1.6  34.9  330  15  7   7.7   4.2 |   2.6  36.7  330  12  6   8.2   4.5
 10000   2.1  35.8  330  14  7   8.1   4.5 |   3.2  37.8  330  11  6   8.3   4.5
  9750   2.8  37.0  325  13  7   9.0   4.9 |   3.8  38.8  330  11  6   8.5   4.6
  9500   3.4  38.1  325  12  6   6.8   3.7 |   4.5  40.1  335  10  5   6.9   3.8
  9250   3.8  38.8  325  12  6   4.7   2.6 |   4.9  40.8  335  10  5   5.2   2.8
  9000   4.2  39.6  325  11  6   6.4   3.5 |   5.3  41.5  340  10  5   7.0   3.8
  8750   4.7  40.5  325  10  5   8.1   4.4 |   5.9  42.6  340   9  5   9.0   5.0
  8500   5.3  41.5  325   9  4   6.1   3.3 |   6.6  43.9  345   9  4   7.8   4.3
  8250   5.6  42.1  325   7  4   4.6   2.5 |   7.1  44.8  345   8  4   6.6   3.6
  8000   6.0  42.8  325   6  3   5.0   2.7 |   7.6  45.7  350   8  4   7.6   4.2
  7750   6.4  43.5  325   5  2   6.2   3.4 |   8.2  46.8  350   7  4   7.0   3.8
  7500   6.9  44.4  330   4  2   7.3   4.0 |   8.6  47.5  355   6  3   5.6   3.0
  7250   7.4  45.3  330   3  2   6.7   3.7 |   9.0  48.2  355   5  3   4.9   2.7
  7000   8.0  46.4  335   2  1   8.1   4.4 |   9.4  48.9  355   4  2   7.0   3.8
  6750   8.6  47.5  340   2  1   9.6   5.3 |  10.0  50.0  360   3  2   8.1   4.4
  6500   9.3  48.7  340   2  1   9.4   5.2 |  10.6  51.1  360   2  1   7.1   3.9
  6250  10.1  50.2  345   2  1   9.5   5.2 |  11.1  52.0  005   2  1   6.5   3.6
  6000  10.8  51.4  345   1  1   9.4   5.1 |  11.7  53.1  020   1  1   9.9   5.4
  5750  11.6  52.9  345   1  1  13.6   7.4 |  12.4  54.3  030   1  0   5.9   3.2
  5500  12.9  55.2  345   1  1  20.9  11.5 |  12.2  54.0  000   0  0 -11.1  -6.1
________________________________________________________________________________

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.

CINH (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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