Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 141507
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0806 MST Sunday, December 14, 2014

This forecast is for Sunday, December 14, 2014:

If the trigger temperature of 42.0 F/5.6 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 7171 ft MSL (0 ft AGL)

Forecast maximum temperature................... 32.0 F/0.5 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............ Between 20 mph and 30 mph
Height of the -3 thermal index................. None
Thermal soaring outlook for Monday 12/15....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:09:50 / 16:37:44 MST
Total possible sunshine........... 9 hr 27 min 55 sec (567 min 55 sec)
Altitude of sun at 11:53:50 MST... 27.88 degrees

Upper air data from numerical model forecast valid on 12/14/2014 at 0500 MST

Freezing level.................. 7820 ft MSL (649 ft AGL)
Convective condensation level... 13987 ft MSL (6816 ft AGL)
Lifted condensation level....... 10162 ft MSL (2991 ft AGL)
Lifted index.................... +8.9
K index......................... +21.0

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  -56.8 -70.2   250   21   11   1.9   1.0      M     M       M      M    M
 45000  -53.9 -65.0   250   25   13   1.9   1.0      M     M       M      M    M
 40000  -51.0 -59.8   205   29   15   1.8   1.0      M     M       M      M    M
 38000  -50.1 -58.2   190   34   17   1.2   0.7      M     M       M      M    M
 36000  -49.3 -56.7   185   37   19   1.2   0.7      M     M       M      M    M
 34000  -48.6 -55.5   185   41   21   1.2   0.7      M     M       M      M    M
 32000  -47.9 -54.2   175   50   26   1.2   0.6      M     M       M      M    M
 30000  -47.2 -53.0   175   60   31   1.7   0.9      M     M       M      M    M
 29000  -45.4 -49.7   175   58   30   7.4   4.0   21.7  71.1    16.8      M    M
 28000  -43.2 -45.8   175   56   29   7.3   4.0   20.7  69.3    16.2      M    M
 27000  -41.0 -41.8   175   53   27   7.3   4.0   19.9  67.8    15.8      M    M
 26000  -38.7 -37.7   175   50   26   7.7   4.2   19.1  66.3    15.3      M    M
 25000  -35.9 -32.6   175   46   24   7.7   4.2   18.0  64.5    14.7      M    M
 24000  -33.6 -28.5   175   43   22   7.7   4.2   17.3  63.2    14.3      M    M
 23000  -31.3 -24.3   175   40   20   7.5   4.1   16.6  61.8    13.8      M    M
 22000  -29.0 -20.2   180   35   18   7.6   4.1   15.7  60.3    13.3      M    M
 21000  -26.8 -16.2   180   31   16   7.6   4.2   15.0  59.1    12.8      M    M
 20000  -24.5 -12.1   180   25   13   7.9   4.3   14.3  57.8    12.3      M    M
 19500  -23.3  -9.9   180   22   11   7.9   4.3   14.0  57.2    12.0      M    M
 19000  -22.2  -8.0   180   19   10   7.9   4.3   13.7  56.6    11.8      M    M
 18500  -21.0  -5.8   175   17    9   8.0   4.4   13.4  56.1    11.6      M    M
 18000  -19.9  -3.8   175   14    7   7.4   4.1   13.1  55.5    11.4      M    M
 17500  -18.8  -1.8   170   12    6   7.3   4.0   12.7  54.8    11.1      M    M
 17000  -17.7   0.1   165   10    5   7.1   3.9   12.3  54.1    10.8      M    M
 16500  -16.7   1.9   160   10    5   6.7   3.7   11.8  53.2    10.3      M    M
 16000  -15.7   3.7   155   10    5   6.7   3.7   11.3  52.3     9.9      M    M
 15500  -14.6   5.7   155   10    5   8.8   4.8   10.9  51.7     9.7      M    M
 15000  -13.3   8.1   155   10    5   8.7   4.7   10.7  51.3     9.5      M    M
 14500  -12.1  10.2   150    9    5   8.1   4.5   10.5  51.0     9.3      M    M
 14000  -10.9  12.4   145    8    4   8.1   4.5   10.3  50.5     9.1      M    M
 13500   -9.8  14.4   135    6    3   7.1   3.9   10.0  49.9     8.8      M    M
 13000   -8.8  16.2   115    6    3   6.7   3.7    9.5  49.0     8.4      M    M
 12500   -7.9  17.8   095    7    3   6.5   3.6    9.0  48.1     7.9      M    M
 12000   -7.0  19.4   070    8    4   3.6   2.0    8.3  47.0     7.3      M    M
 11750   -6.9  19.6   055   10    5   2.0   1.1    7.7  45.9     6.8      M    M
 11500   -6.7  19.9   045   12    6   2.3   1.2    7.2  44.9     6.3      M    M
 11250   -6.5  20.3   040   14    7   1.8   1.0    6.5  43.8     5.7      M    M
 11000   -6.4  20.5   035   15    8   2.5   1.4    5.9  42.7     5.2      M    M
 10750   -6.1  21.0   035   17    9   3.9   2.1    5.4  41.8     4.7      M    M
 10500   -5.8  21.6   030   19   10   5.7   3.1    5.0  41.1     4.3      M    M
 10250   -5.3  22.5   025   20   10   6.6   3.6    4.8  40.6     4.1      M    M
 10000   -4.8  23.4   025   21   11   6.2   3.4    4.5  40.1     3.8      M    M
  9750   -3.8  25.2   025   23   12   7.3   4.0    4.1  39.3     3.4      M    M
  9500   -3.3  26.1   025   23   12   7.1   3.9    3.9  39.0     3.2      M    M
  9250   -2.7  27.1   025   24   12   7.1   3.9    3.7  38.6     3.1      M    M
  9000   -2.2  28.0   025   24   12   7.2   4.0    3.5  38.2     2.9      M    M
  8750   -1.6  29.1   025   23   12   6.5   3.5    3.3  37.9     2.7      M    M
  8500   -1.2  29.8   025   22   11   6.0   3.3    3.0  37.3     2.4      M    M
  8250   -0.7  30.7   025   20   11   5.4   3.0    2.7  36.8     2.2      M    M
  8000   -0.2  31.6   025   19   10   8.2   4.5    2.4  36.3     1.9      M    M
  7750    0.4  32.7   020   17    9   7.1   3.9    2.4  36.2     1.9      M    M
  7500    0.6  33.1   015   12    6  -2.8  -1.5    1.8  35.2     1.3      M    M
  7250    0.7  33.3   355    8    4  17.3   9.5    1.2  34.2     0.7      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 * * * * * *

           12/14/2014 at 0800 MST          |       12/14/2014 at 1100 MST
                                           |
K index... +20.8  LI... -0.6               | K index... +17.9  LI... +0.1
CAPE... +57.1  CIN... -1.8                 | CAPE... +18.2  CIN... -1.4
                                           |
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 -56.5 -69.7  260  21 11   1.8   1.0 | -56.8 -70.2  270  24 13   1.8   1.0
 45000 -53.8 -64.8  260  18  9   1.8   1.0 | -54.2 -65.6  270  25 13   1.6   0.9
 40000 -50.1 -58.2  235  21 11   2.4   1.3 | -49.2 -56.6  270  20 11   3.2   1.8
 38000 -48.9 -56.0  220  22 11   1.0   0.5 | -47.8 -54.0  265  18  9   0.9   0.5
 36000 -48.4 -55.1  200  23 12   1.0   0.5 | -47.2 -53.0  250  14  7   0.9   0.5
 34000 -47.8 -54.0  180  26 14   1.0   0.5 | -46.7 -52.1  230  12  6   0.9   0.5
 32000 -47.1 -52.8  175  33 17   1.1   0.6 | -45.9 -50.6  185  11  6   1.3   0.7
 30000 -46.4 -51.5  170  40 21   0.9   0.5 | -45.1 -49.2  155  17  9   0.9   0.5
 29000 -44.8 -48.6  165  42 22   6.5   3.6 | -43.9 -47.0  145  23 12   4.9   2.7
 28000 -42.9 -45.2  165  44 23   6.5   3.6 | -42.5 -44.5  140  29 15   4.9   2.7
 27000 -40.9 -41.6  160  46 24   6.5   3.6 | -41.0 -41.8  140  35 18   4.9   2.7
 26000 -39.0 -38.2  160  46 24   6.8   3.7 | -38.9 -38.0  135  40 21   6.8   3.7
 25000 -36.4 -33.5  160  41 21   6.8   3.7 | -36.8 -34.2  135  40 21   6.9   3.8
 24000 -34.4 -29.9  160  36 19   6.9   3.8 | -34.7 -30.5  135  40 21   7.0   3.8
 23000 -32.2 -26.0  165  31 16   7.9   4.4 | -32.5 -26.5  135  38 19   8.3   4.5
 22000 -29.8 -21.6  165  26 13   8.0   4.4 | -30.0 -22.0  135  32 16   8.3   4.5
 21000 -27.4 -17.3  165  20 10   8.0   4.4 | -27.5 -17.5  135  26 13   8.3   4.6
 20000 -25.0 -13.0  160  16  8   8.1   4.5 | -25.1 -13.2  135  21 11   8.1   4.5
 19500 -23.8 -10.8  155  15  8   8.1   4.5 | -23.9 -11.0  135  18 10   8.1   4.5
 19000 -22.6  -8.7  150  14  7   8.2   4.5 | -22.7  -8.9  130  16  8   8.1   4.5
 18500 -21.4  -6.5  140  13  7   8.2   4.5 | -21.5  -6.7  125  14  7   8.2   4.5
 18000 -20.2  -4.4  135  12  6   8.2   4.5 | -20.3  -4.5  120  12  6   7.8   4.3
 17500 -19.0  -2.2  120  11  6   8.2   4.5 | -19.1  -2.4  110  10  5   7.7   4.3
 17000 -17.8  -0.0  110  11  6   7.8   4.3 | -18.0  -0.4  095   9  4   7.5   4.1
 16500 -16.8   1.8  105  11  6   7.0   3.8 | -17.0   1.4  090   8  4   6.5   3.6
 16000 -15.7   3.7  105  11  6   7.0   3.8 | -16.1   3.0  080   8  4   6.5   3.6
 15500 -14.7   5.5  105  11  6   7.4   4.1 | -15.1   4.8  075   7  4   6.8   3.7
 15000 -13.6   7.5  105  11  5   7.4   4.1 | -14.1   6.6  070   7  3   6.8   3.7
 14500 -12.5   9.5  105  10  5   7.2   3.9 | -13.1   8.4  065   6  3   7.4   4.1
 14000 -11.5  11.3  100  10  5   7.2   3.9 | -12.0  10.4  055   6  3   7.6   4.1
 13500 -10.5  13.1  095  10  5   7.6   4.2 | -10.9  12.4  050   7  4   7.3   4.0
 13000  -9.3  15.3  090  10  5   7.8   4.3 |  -9.9  14.2  040   8  4   7.1   3.9
 12500  -8.2  17.2  085  11  5   8.2   4.5 |  -8.9  16.0  030  10  5   7.7   4.2
 12000  -7.0  19.4  080  11  6   5.0   2.8 |  -7.7  18.1  030  11  6   6.1   3.3
 11750  -6.8  19.8  075  12  6   2.5   1.4 |  -7.3  18.9  025  12  6   4.1   2.3
 11500  -6.6  20.1  070  12  6   3.3   1.8 |  -7.0  19.4  025  13  7   4.4   2.4
 11250  -6.3  20.7  060  13  7   3.4   1.9 |  -6.7  19.9  020  15  8   4.1   2.2
 11000  -6.0  21.2  055  14  7   3.3   1.8 |  -6.3  20.7  015  16  8   3.9   2.1
 10750  -5.8  21.6  045  15  8   1.5   0.8 |  -6.1  21.0  015  17  9   1.9   1.0
 10500  -5.7  21.7  040  17  9   2.8   1.6 |  -6.0  21.2  010  19 10   1.8   1.0
 10250  -5.3  22.5  035  20 10   4.9   2.7 |  -5.8  21.6  005  22 11   3.2   1.7
 10000  -4.6  23.7  025  26 13   4.3   2.4 |  -5.3  22.5  360  26 14   3.9   2.1
  9750  -4.4  24.1  025  27 14   3.3   1.8 |  -5.1  22.8  360  28 14   1.9   1.0
  9500  -4.2  24.4  020  29 15   2.8   1.5 |  -5.1  22.8  355  30 16  -0.8  -0.4
  9250  -4.0  24.8  020  32 16   3.2   1.8 |  -5.1  22.8  355  33 17   0.0   0.0
  9000  -3.8  25.2  015  34 17   1.9   1.0 |  -5.2  22.6  355  36 19  -0.5  -0.3
  8750  -3.7  25.3  015  34 18   3.2   1.7 |  -5.1  22.8  355  37 19   4.5   2.4
  8500  -3.3  26.1  010  33 17   5.5   3.0 |  -4.6  23.7  355  36 18   8.5   4.7
  8250  -3.0  26.6  005  31 16   4.6   2.5 |  -4.0  24.8  350  35 18   7.1   3.9
  8000  -2.6  27.3  005  30 16   5.9   3.2 |  -3.4  25.9  350  34 17   8.8   4.8
  7750  -2.0  28.4  360  28 14   8.7   4.8 |  -2.6  27.3  350  31 16  13.6   7.4
  7500  -1.3  29.7  360  23 12  10.3   5.6 |  -1.5  29.3  350  26 13  17.1   9.4
  7250  -0.6  30.9  355  18  9   8.3   4.6 |  -0.3  31.5  350  21 11  12.1   6.6
  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

           12/14/2014 at 1400 MST          |       12/14/2014 at 1700 MST
                                           |
K index... +14.2  LI... +1.1               | K index... +10.6  LI... +2.3
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.9
                                           |
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 -56.9 -70.4  285  31 16   1.6   0.9 | -57.0 -70.6  295  38 20   1.9   1.1
 45000 -54.5 -66.1  295  35 18   1.5   0.8 | -54.1 -65.4  295  45 23   1.8   1.0
 40000 -49.6 -57.3  295  36 19   3.2   1.8 | -49.1 -56.4  300  51 26   3.2   1.8
 38000 -48.0 -54.4  295  34 17   1.2   0.7 | -47.7 -53.9  300  50 26   0.8   0.5
 36000 -47.3 -53.1  295  27 14   1.3   0.7 | -47.2 -53.0  300  43 22   0.9   0.5
 34000 -46.5 -51.7  295  19 10   1.2   0.7 | -46.7 -52.1  300  36 19   0.9   0.5
 32000 -45.6 -50.1  295   9  5   1.5   0.8 | -46.2 -51.2  305  24 13   0.9   0.5
 30000 -44.7 -48.5  180   2  1   1.3   0.7 | -45.6 -50.1  315  12  6   0.7   0.4
 29000 -43.8 -46.8  110   7  3   3.6   2.0 | -44.3 -47.7  340  10  5   5.2   2.8
 28000 -42.7 -44.9  100  13  7   3.6   2.0 | -42.8 -45.0  010  10  5   5.2   2.8
 27000 -41.6 -42.9  095  20 10   3.6   2.0 | -40.9 -41.6  035  13  7   5.1   2.8
 26000 -39.2 -38.6  090  25 13   9.7   5.3 | -38.8 -37.8  040  14  7   8.1   4.4
 25000 -36.3 -33.3  085  25 13   9.9   5.4 | -36.4 -33.5  035  13  7   8.1   4.5
 24000 -33.3 -27.9  080  26 13   9.8   5.4 | -34.0 -29.2  035  12  6   8.1   4.5
 23000 -30.8 -23.4  075  24 12   6.9   3.8 | -31.5 -24.7  025  11  6   8.4   4.6
 22000 -28.7 -19.7  075  18  9   6.9   3.8 | -29.0 -20.2  015  11  6   8.5   4.6
 21000 -26.7 -16.1  065  13  7   6.9   3.8 | -26.4 -15.5  005  11  6   8.5   4.7
 20000 -24.6 -12.3  050   9  4   7.0   3.9 | -24.0 -11.2  350  12  6   7.8   4.3
 19500 -23.5 -10.3  030   7  4   7.0   3.9 | -22.9  -9.2  345  12  6   7.8   4.3
 19000 -22.5  -8.5  005   6  3   7.0   3.9 | -21.7  -7.1  340  13  7   7.8   4.3
 18500 -21.4  -6.5  340   7  4   7.0   3.8 | -20.5  -4.9  330  14  7   7.8   4.3
 18000 -20.4  -4.7  330   9  4   7.6   4.2 | -19.4  -2.9  330  15  7   7.2   4.0
 17500 -19.2  -2.6  340  11  6   7.8   4.3 | -18.3  -0.9  330  15  8   7.1   3.9
 17000 -18.1  -0.6  350  14  7   7.7   4.2 | -17.3   0.9  330  16  8   7.4   4.1
 16500 -17.0   1.4  355  15  8   7.3   4.0 | -16.1   3.0  335  17  9   8.3   4.5
 16000 -15.9   3.4  355  17  9   7.1   3.9 | -14.9   5.2  340  18  9   8.4   4.6
 15500 -14.7   5.5  360  17  9   9.9   5.4 | -13.7   7.3  345  19 10   7.1   3.9
 15000 -13.2   8.2  360  18  9  10.0   5.5 | -12.7   9.1  345  22 11   7.4   4.0
 14500 -11.9  10.6  360  19 10   5.6   3.1 | -11.7  10.9  345  24 12   5.6   3.0
 14000 -11.4  11.5  360  20 10   4.1   2.3 | -10.9  12.4  345  27 14   5.1   2.8
 13500 -10.8  12.6  355  22 11   4.6   2.5 | -10.2  13.6  345  31 16   4.3   2.3
 13000 -10.0  14.0  350  26 13   5.3   2.9 |  -9.7  14.5  340  35 18   3.7   2.0
 12500  -9.2  15.4  345  29 15   6.3   3.5 |  -9.1  15.6  340  39 20   3.5   1.9
 12000  -8.1  17.4  345  31 16   5.9   3.3 |  -8.7  16.3  340  41 21   3.4   1.9
 11750  -7.8  18.0  345  33 17   3.8   2.1 |  -8.4  16.9  340  43 22   3.5   1.9
 11500  -7.4  18.7  340  34 18   5.2   2.9 |  -8.1  17.4  340  45 23   3.9   2.1
 11250  -7.0  19.4  340  36 18   6.6   3.6 |  -7.8  18.0  340  46 24   4.4   2.4
 11000  -6.5  20.3  340  37 19   6.3   3.5 |  -7.5  18.5  340  47 24   4.3   2.4
 10750  -6.1  21.0  340  38 20   4.8   2.6 |  -7.2  19.0  340  48 25   5.1   2.8
 10500  -5.8  21.6  340  40 20   3.2   1.7 |  -6.8  19.8  340  48 25   4.2   2.3
 10250  -5.6  21.9  340  41 21   2.4   1.3 |  -6.4  20.5  340  48 25   3.3   1.8
 10000  -5.3  22.5  340  43 22   2.0   1.1 |  -6.1  21.0  345  47 24   3.1   1.7
  9750  -5.2  22.6  340  43 22   0.3   0.2 |  -6.0  21.2  345  46 24   1.7   0.9
  9500  -5.2  22.6  340  43 22  -0.5  -0.3 |  -5.9  21.4  345  46 23   1.0   0.6
  9250  -5.3  22.5  345  44 22  -0.1  -0.0 |  -5.8  21.6  350  45 23   0.8   0.5
  9000  -5.3  22.5  345  44 23  -0.9  -0.5 |  -5.7  21.7  350  44 23   2.2   1.2
  8750  -5.3  22.5  345  43 22   3.8   2.1 |  -5.4  22.3  350  42 21   5.5   3.0
  8500  -4.8  23.4  345  41 21   8.3   4.5 |  -5.0  23.0  350  39 20   6.5   3.6
  8250  -4.2  24.4  345  38 20   6.7   3.7 |  -4.5  23.9  350  37 19   6.1   3.4
  8000  -3.7  25.3  345  36 19   8.5   4.7 |  -4.1  24.6  350  34 18   6.7   3.7
  7750  -2.9  26.8  345  34 17  13.7   7.5 |  -3.5  25.7  350  31 16   9.2   5.0
  7500  -1.7  28.9  345  28 15  17.9   9.8 |  -2.7  27.1  350  25 13  11.7   6.4
  7250  -0.5  31.1  345  23 12  11.6   6.4 |  -1.9  28.6  350  19 10   7.7   4.2
  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) 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 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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