Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 211304
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0604 MST Tuesday, November 21, 2017

This forecast is for Tuesday, November 21, 2017:

If the trigger temperature of 53.7 F/12.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 9295 ft MSL (1708 ft AGL)

Forecast maximum temperature................... 50.0 F/10.5 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8640 ft MSL (1053 ft AGL)
Thermal soaring outlook for Wednesday 11/22.... Fair

Wave Soaring Index............................. Not available

Remarks...

Sunrise/Sunset.................... 06:49:18 / 16:41:13 MST
Total possible sunshine........... 9 hr 51 min 55 sec (591 min 55 sec)
Altitude of sun at 11:45:16 MST... 30.85 degrees

Upper air data from numerical model forecast valid on 11/21/2017 at 0500 MST

Freezing level.................. 11623 ft MSL (4036 ft AGL)
Convective condensation level... 16260 ft MSL (8673 ft AGL)
Lifted condensation level....... 14876 ft MSL (7289 ft AGL)
Lifted index.................... +5.3
K index......................... +10.6

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  -61.9 -79.4   325   29   15   1.2   0.7      M     M       M      M    M
 45000  -59.9 -75.8   325   47   24   2.4   1.3      M     M       M      M    M
 40000  -56.4 -69.5   325   55   28   2.3   1.3      M     M       M      M    M
 38000  -54.1 -65.4   325   60   31   4.6   2.6      M     M       M      M    M
 36000  -51.3 -60.3   325   65   34   4.6   2.5      M     M       M      M    M
 34000  -48.2 -54.8   325   69   35   7.0   3.9      M     M       M      M    M
 32000  -43.4 -46.1   320   65   33   7.1   3.9      M     M       M      M    M
 30000  -39.6 -39.3   320   61   31   5.2   2.8   29.6  85.3    15.1      M    M
 29000  -38.0 -36.4   320   58   30   5.1   2.8   27.8  82.0    13.9      M    M
 28000  -36.5 -33.7   320   54   28   5.1   2.8   26.1  79.0    12.7      M    M
 27000  -34.9 -30.8   320   51   26   6.6   3.6   24.6  76.2    11.6      M    M
 26000  -32.9 -27.2   325   47   24   6.7   3.7   23.3  74.0    10.7      M    M
 25000  -30.9 -23.6   325   43   22   6.7   3.7   22.2  72.0    10.0      M    M
 24000  -28.9 -20.0   325   39   20   6.9   3.8   21.3  70.3     9.3      M    M
 23000  -26.8 -16.2   325   36   18   7.0   3.9   20.2  68.3     8.5      M    M
 22000  -24.7 -12.5   325   33   17   7.0   3.9   19.2  66.6     7.8      M    M
 21000  -22.6  -8.7   325   30   15   6.5   3.6   18.3  65.0     7.0      M    M
 20000  -20.7  -5.3   325   28   15   6.4   3.5   17.1  62.8     6.1      M    M
 19500  -19.8  -3.6   325   28   14   6.4   3.5   16.6  61.8     5.6      M    M
 19000  -18.8  -1.8   325   27   14   6.4   3.5   16.0  60.8     5.2      M    M
 18500  -17.3   0.9   325   25   13   7.6   4.2   15.3  59.6     4.6      M    M
 18000  -16.1   3.0   325   23   12   7.5   4.1   15.0  58.9     4.3      M    M
 17500  -15.0   5.0   325   21   11   7.7   4.3   14.6  58.3     4.0      M    M
 17000  -13.9   7.0   325   20   10   7.9   4.3   14.3  57.7     3.7      M    M
 16500  -12.7   9.1   325   19   10   8.1   4.5   14.0  57.1     3.4      M    M
 16000  -11.5  11.3   330   17    9   9.0   4.9   13.8  56.8     3.2      M    M
 15500  -10.2  13.6   330   15    8   9.0   4.9   13.7  56.6     3.1      M    M
 15000   -8.8  16.2   335   15    8   8.8   4.8   13.5  56.3     2.9      M    M
 14500   -7.5  18.5   340   15    8   8.8   4.8   13.4  56.0     2.8      M    M
 14000   -6.2  20.8   340   16    8   8.8   4.8   13.2  55.8     2.7      M    M
 13500   -4.9  23.2   345   17    9   8.8   4.8   13.1  55.5     2.5      M    M
 13000   -3.6  25.5   345   19   10   9.7   5.3   12.9  55.3     2.4      M    M
 12500   -2.2  28.0   340   19   10   8.0   4.4   12.8  55.1     2.3      M    M
 12000   -1.0  30.2   340   20   11   8.6   4.7   12.6  54.7     2.1      M    M
 11750   -0.4  31.3   335   21   11   9.0   4.9   12.5  54.5     2.0      M    M
 11500    0.3  32.5   335   21   11   8.8   4.8   12.5  54.4     2.0      M    M
 11250    0.9  33.6   335   21   11   8.9   4.9   12.4  54.3     1.9      M    M
 11000    1.6  34.9   330   22   11   7.5   4.1   12.3  54.1     1.8      M    M
 10750    2.0  35.6   330   22   11   6.5   3.6   12.0  53.7     1.5      M    M
 10500    2.5  36.5   325   22   12   6.6   3.6   11.8  53.3     1.3      M    M
 10250    3.1  37.6   325   23   12   8.4   4.6   11.6  52.9     1.1      M    M
 10000    3.7  38.7   325   23   12   7.5   4.1   11.5  52.8     1.0      M    M
  9750    4.1  39.4   320   23   12   4.8   2.6   11.2  52.2     0.7      M    M
  9500    4.5  40.1   320   23   12   7.0   3.8   10.9  51.6     0.4      M    M
  9250    4.9  40.8   315   23   12   0.8   0.4   10.6  51.1     0.0      M    M
  9000    4.6  40.3   315   23   12  -6.4  -3.5    9.5  49.1    -1.0    138  0.7
  8750    4.1  39.4   310   21   11  -5.4  -3.0    8.3  47.0    -2.2    143  0.7
  8500    3.7  38.7   305   20   10  -6.4  -3.5    7.2  44.9    -3.3    148  0.8
  8250    3.3  37.9   300   18    9  -3.5  -1.9    6.0  42.8    -4.5    154  0.8
  8000    3.2  37.8   300   17    9  -1.6  -0.9    5.2  41.3    -5.3    150  0.8
  7750    2.9  37.2   300   11    6  -6.9  -3.8    4.1  39.4    -6.4    152  0.8
  7500      M     M     M    M    M     M     M      M     M       M      M    M
  7250      M     M     M    M    M     M     M      M     M       M      M    M
  7000      M     M     M    M    M     M     M      M     M       M      M    M
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           11/21/2017 at 0800 MST          |       11/21/2017 at 1100 MST
                                           |
CAPE...     0.0    LI...       +1.4        | CAPE...    +5.2    LI...       +4.1
CINH...     0.0    K Index... +11.7        | CINH...     0.0    K Index...  +6.2
                                           |
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 -63.6 -82.5  330  29 15   1.9   1.0 | -63.5 -82.3  335  35 18   2.8   1.6
 45000 -60.5 -76.9  340  42 22   3.4   1.8 | -59.3 -74.7  340  49 25   1.3   0.7
 40000 -55.5 -67.9  330  49 25   3.4   1.8 | -57.4 -71.3  335  52 27   1.3   0.7
 38000 -53.0 -63.4  330  53 28   4.5   2.4 | -54.4 -65.9  335  52 27   6.2   3.4
 36000 -50.4 -58.7  335  59 30   4.5   2.4 | -50.7 -59.3  340  50 26   6.2   3.4
 34000 -46.6 -51.9  335  64 33   7.5   4.1 | -46.0 -50.8  340  52 27   8.1   4.5
 32000 -42.2 -44.0  330  68 35   7.4   4.1 | -41.1 -42.0  335  57 29   8.1   4.5
 30000 -37.7 -35.9  325  69 35   7.6   4.1 | -36.6 -33.9  335  58 30   6.7   3.7
 29000 -35.5 -31.9  325  66 34   7.5   4.1 | -34.6 -30.3  335  55 28   6.7   3.7
 28000 -33.2 -27.8  330  64 33   7.6   4.1 | -32.6 -26.7  340  53 27   6.7   3.7
 27000 -31.2 -24.2  330  62 32   3.4   1.9 | -30.6 -23.1  340  49 25   6.5   3.6
 26000 -30.4 -22.7  330  57 30   2.6   1.4 | -28.6 -19.5  340  43 22   6.6   3.6
 25000 -29.7 -21.5  330  53 27   2.6   1.4 | -26.6 -15.9  345  37 19   6.6   3.6
 24000 -28.9 -20.0  335  48 25   4.0   2.2 | -24.7 -12.5  345  32 17   5.4   3.0
 23000 -27.1 -16.8  330  44 23   6.1   3.3 | -23.2  -9.8  345  33 17   5.0   2.7
 22000 -25.3 -13.5  330  40 21   6.1   3.3 | -21.7  -7.1  345  33 17   5.0   2.7
 21000 -23.5 -10.3  330  37 19   6.0   3.3 | -20.2  -4.4  340  33 17   5.7   3.1
 20000 -21.3  -6.3  325  33 17   6.0   3.3 | -18.1  -0.6  340  33 17   5.7   3.1
 19500 -20.4  -4.7  325  31 16   6.0   3.3 | -17.2   1.0  340  34 17   5.7   3.1
 19000 -19.5  -3.1  325  30 15   6.0   3.3 | -16.4   2.5  335  34 17   5.4   3.0
 18500 -18.7  -1.7  325  29 15   6.1   3.3 | -15.9   3.4  335  32 16   2.2   1.2
 18000 -17.8  -0.0  320  28 14   6.1   3.3 | -15.6   3.9  330  28 15   2.4   1.3
 17500 -16.9   1.6  320  27 14   6.5   3.6 | -15.1   4.8  325  25 13   4.1   2.3
 17000 -15.9   3.4  320  25 13   6.7   3.7 | -14.5   5.9  320  22 11   4.6   2.5
 16500 -14.9   5.2  320  24 12   6.9   3.8 | -13.9   7.0  315  19 10   5.5   3.0
 16000 -13.8   7.2  320  22 11   7.5   4.1 | -12.9   8.8  315  17  9   7.0   3.9
 15500 -12.7   9.1  320  20 10   7.6   4.2 | -11.9  10.6  315  16  8   7.0   3.9
 15000 -11.7  10.9  320  19 10   6.8   3.8 | -11.0  12.2  315  16  8   5.8   3.2
 14500 -10.7  12.7  325  17  9   7.0   3.8 | -10.1  13.8  320  16  8   5.9   3.2
 14000  -9.7  14.5  330  16  8   6.6   3.6 |  -9.2  15.4  325  16  8   6.1   3.3
 13500  -8.7  16.3  335  17  9   6.5   3.6 |  -8.4  16.9  325  16  8   6.0   3.3
 13000  -7.7  18.1  340  18  9   7.7   4.2 |  -7.5  18.5  325  16  8   6.3   3.5
 12500  -6.5  20.3  345  19 10   8.4   4.6 |  -6.5  20.3  325  15  8   6.2   3.4
 12000  -5.3  22.5  345  19 10   8.8   4.8 |  -5.6  21.9  330  15  8   6.4   3.5
 11750  -4.6  23.7  345  19 10   8.9   4.9 |  -5.2  22.6  330  15  8   6.6   3.6
 11500  -3.9  25.0  350  20 10   9.3   5.1 |  -4.7  23.5  330  15  8   5.8   3.2
 11250  -3.2  26.2  350  20 10  10.0   5.5 |  -4.4  24.1  330  14  7   4.0   2.2
 11000  -2.5  27.5  350  20 10   9.3   5.1 |  -4.1  24.6  330  14  7   4.0   2.2
 10750  -1.8  28.8  350  19 10   9.0   4.9 |  -3.8  25.2  330  13  7   4.4   2.4
 10500  -1.1  30.0  350  19 10   8.7   4.8 |  -3.4  25.9  330  12  6   4.6   2.5
 10250  -0.5  31.1  350  19 10  10.5   5.8 |  -3.1  26.4  330  12  6   3.6   2.0
 10000   0.3  32.5  345  19 10   8.7   4.8 |  -2.9  26.8  335  11  5   2.9   1.6
  9750   0.8  33.4  345  19 10   5.6   3.0 |  -2.7  27.1  335  10  5   3.5   1.9
  9500   1.2  34.2  345  18  9   6.6   3.6 |  -2.4  27.7  340   9  5   3.4   1.9
  9250   1.7  35.1  340  18  9   5.7   3.1 |  -2.2  28.0  345   9  5   2.8   1.5
  9000   2.0  35.6  340  16  8   3.9   2.1 |  -2.0  28.4  345   9  4   4.6   2.5
  8750   2.3  36.1  340  14  7   2.7   1.5 |  -1.5  29.3  350   8  4   6.4   3.5
  8500   2.5  36.5  340  13  7   4.0   2.2 |  -1.1  30.0  350   8  4   6.1   3.4
  8250   2.7  36.9  335  11  6  -0.8  -0.4 |  -0.7  30.7  350   7  4   5.9   3.2
  8000   2.4  36.3  335  10  5  -4.9  -2.7 |  -0.1  31.8  345   6  3  11.6   6.4
  7750   2.3  36.1  325   7  4   1.9   1.0 |   1.2  34.2  340   5  3  22.7  12.5
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           11/21/2017 at 1400 MST          |       11/21/2017 at 1700 MST
                                           |
CAPE...    +4.1    LI...       +5.1        | CAPE...    +0.6    LI...      +10.0
CINH...    -1.2    K Index...  -8.1        | CINH...    -4.1    K Index... -28.3
                                           |
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 -64.3 -83.7  325  36 18   0.7   0.4 | -67.3 -89.1  325  40 20  -1.4  -0.8
 45000 -63.0 -81.4  325  50 26   2.4   1.3 | -68.4 -91.1  330  58 30   4.8   2.7
 40000 -59.4 -74.9  335  49 25   2.4   1.3 | -60.8 -77.4  345  60 31   4.7   2.6
 38000 -55.8 -68.4  340  48 25   6.9   3.8 | -55.3 -67.5  345  58 30   8.6   4.7
 36000 -51.1 -60.0  345  47 24   6.9   3.8 | -50.1 -58.2  345  55 28   8.6   4.7
 34000 -46.4 -51.5  345  49 25   8.6   4.7 | -44.9 -48.8  345  53 27   8.7   4.8
 32000 -41.2 -42.2  340  52 27   8.6   4.7 | -39.7 -39.5  345  50 26   8.7   4.8
 30000 -36.1 -33.0  340  54 28   8.3   4.6 | -34.9 -30.8  345  47 24   7.3   4.0
 29000 -33.7 -28.7  345  55 28   8.3   4.6 | -32.7 -26.9  350  45 23   7.3   4.0
 28000 -31.2 -24.2  345  55 28   8.3   4.5 | -30.5 -22.9  350  44 23   7.3   4.0
 27000 -28.8 -19.8  345  55 28   7.2   4.0 | -28.2 -18.8  350  43 22   8.1   4.4
 26000 -26.6 -15.9  350  53 27   7.3   4.0 | -25.8 -14.4  350  42 22   8.1   4.4
 25000 -24.5 -12.1  350  52 27   7.3   4.0 | -23.4 -10.1  355  42 22   8.1   4.4
 24000 -22.3  -8.1  350  49 25   6.2   3.4 | -21.1  -6.0  355  41 21   6.3   3.5
 23000 -20.5  -4.9  350  41 21   6.1   3.4 | -18.7  -1.7  360  39 20   6.5   3.6
 22000 -18.2  -0.8  350  30 15   6.0   3.3 | -16.7   1.9  360  38 19   6.5   3.6
 21000 -16.8   1.8  345  24 13   3.3   1.8 | -14.6   5.7  360  33 17   7.3   4.0
 20000 -15.8   3.6  345  22 11   3.2   1.8 | -12.4   9.7  355  27 14   7.3   4.0
 19500 -15.3   4.5  345  21 11   3.2   1.7 | -11.3  11.7  350  24 12   7.3   4.0
 19000 -14.8   5.4  340  20 10   3.0   1.7 | -10.2  13.6  350  21 11   5.9   3.3
 18500 -14.5   5.9  340  20 10   1.8   1.0 |  -9.7  14.5  345  19 10   2.6   1.4
 18000 -14.3   6.3  340  20 10   1.9   1.0 |  -9.3  15.3  340  18  9   3.0   1.6
 17500 -14.0   6.8  340  21 11   2.0   1.1 |  -9.1  15.6  335  17  9  -1.2  -0.7
 17000 -13.7   7.3  335  20 10   2.1   1.2 |  -9.3  15.3  335  17  9  -1.6  -0.9
 16500 -13.4   7.9  330  19 10   2.6   1.4 |  -9.6  14.7  335  17  9  -1.9  -1.0
 16000 -13.0   8.6  325  18  9   3.4   1.9 |  -9.9  14.2  335  16  8  -2.3  -1.2
 15500 -12.5   9.5  315  17  9   3.5   1.9 | -10.3  13.5  335  15  8  -1.9  -1.0
 15000 -11.7  10.9  310  16  8   7.1   3.9 | -10.2  13.6  335  15  8   3.1   1.7
 14500 -10.8  12.6  310  17  9   6.7   3.7 |  -9.8  14.4  330  14  7   2.5   1.4
 14000  -9.7  14.5  310  16  8   8.3   4.6 |  -9.2  15.4  325  13  6   6.0   3.3
 13500  -8.5  16.7  305  15  8   8.3   4.6 |  -8.4  16.9  320  12  6   5.7   3.1
 13000  -7.4  18.7  305  14  7   7.7   4.2 |  -7.5  18.5  310  10  5   8.4   4.6
 12500  -6.2  20.8  310  13  7   8.6   4.7 |  -6.4  20.5  305   9  5   7.5   4.1
 12000  -5.0  23.0  310  12  6   7.5   4.1 |  -5.2  22.6  300   9  4   9.6   5.3
 11750  -4.5  23.9  310  11  6   7.0   3.9 |  -4.5  23.9  300   8  4   9.7   5.3
 11500  -4.0  24.8  305  11  5   7.9   4.3 |  -3.8  25.2  300   8  4   9.9   5.5
 11250  -3.4  25.9  305  10  5   7.1   3.9 |  -3.0  26.6  300   8  4   8.5   4.7
 11000  -3.0  26.6  305   9  5   4.2   2.3 |  -2.5  27.5  295   8  4   6.3   3.4
 10750  -2.7  27.1  305   9  5   3.7   2.0 |  -2.1  28.2  295   7  4   6.1   3.3
 10500  -2.4  27.7  305   8  4   3.3   1.8 |  -1.6  29.1  290   6  3   5.8   3.2
 10250  -2.2  28.0  305   7  4   5.4   3.0 |  -1.2  29.8  285   6  3   7.1   3.9
 10000  -1.7  28.9  305   6  3   5.3   2.9 |  -0.7  30.7  275   5  3   6.1   3.4
  9750  -1.4  29.5  310   5  2   3.2   1.8 |  -0.3  31.5  265   5  2   4.1   2.3
  9500  -1.2  29.8  320   4  2   3.3   1.8 |  -0.0  32.0  245   4  2   4.9   2.7
  9250  -0.9  30.4  330   3  1   5.6   3.1 |   0.3  32.5  230   4  2   3.3   1.8
  9000  -0.4  31.3  340   2  1   9.4   5.2 |   0.5  32.9  220   4  2   3.2   1.7
  8750   0.4  32.7  355   2  1   9.8   5.4 |   0.8  33.4  205   4  2   4.1   2.2
  8500   1.1  34.0  010   2  1   9.8   5.4 |   1.0  33.8  190   5  2   4.3   2.3
  8250   1.8  35.2  020   2  1   9.8   5.4 |   1.4  34.5  180   5  3   6.6   3.6
  8000   2.6  36.7  020   2  1  13.3   7.3 |   1.8  35.2  170   4  2  -4.5  -2.5
  7750   3.9  39.0  025   2  1  19.6  10.7 |   1.7  35.1  165   3  1  10.8   5.9
  7500     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7250     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  7000     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 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 Air Force Academy
in Colorado Springs, Colorado at

                   North Latitude:  38 deg 58 min 48.000 sec
                   West Longitude: 104 deg 49 min 12.000 sec
                   Elevation: 6572 feet (2003 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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