Soaring Guidance
Issued by NWS Pueblo, CO

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571
UXUS97 KPUB 091411
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0711 MST Friday, December 9, 2016

This forecast is for Friday, December 9, 2016:

If the trigger temperature of 46.6 F/8.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 54 ft/min (0.3 m/s)
   Maximum height of thermals.................. 8150 ft MSL (1392 ft AGL)

Forecast maximum temperature................... 44.0 F/7.1 C
Time of trigger temperature.................... None
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................. 7770 ft MSL (1013 ft AGL)
Thermal soaring outlook for Saturday 12/10..... Fair

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

Remarks...

Sunrise/Sunset.................... 07:06:25 / 16:36:56 MST
Total possible sunshine........... 9 hr 30 min 31 sec (570 min 31 sec)
Altitude of sun at 11:51:45 MST... 28.21 degrees

Upper air data from numerical model forecast valid on 12/09/2016 at 0500 MST

Freezing level.................. 7361 ft MSL (603 ft AGL)
Additional freezing level....... 9437 ft MSL (2679 ft AGL)
Convective condensation level... 16574 ft MSL (9816 ft AGL)
Lifted condensation level....... 13350 ft MSL (6593 ft AGL)
Lifted index.................... +6.8
K index......................... +12.1

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  -61.7 -79.1   285   71   36   0.9   0.5      M     M       M      M    M
 45000  -60.3 -76.5   285   75   39   1.0   0.6      M     M       M      M    M
 40000  -60.9 -77.6   290   67   34  -0.5  -0.3      M     M       M      M    M
 38000  -60.5 -76.9   290   64   33   3.0   1.6      M     M       M      M    M
 36000  -58.8 -73.8   295   62   32   3.0   1.6      M     M       M      M    M
 34000  -56.2 -69.2   295   61   32   8.7   4.8      M     M       M      M    M
 32000  -51.3 -60.3   295   64   33   8.3   4.5      M     M       M      M    M
 30000  -46.2 -51.2   295   66   34   8.8   4.8   23.2  73.8    12.7      M    M
 29000  -43.6 -46.5   300   66   34   8.8   4.8   22.8  73.0    12.5      M    M
 28000  -40.9 -41.6   300   65   34   8.8   4.8   22.4  72.4    12.4      M    M
 27000  -38.3 -36.9   300   65   33   8.5   4.7   22.2  72.0    12.4      M    M
 26000  -35.9 -32.6   300   65   34   8.0   4.4   21.5  70.7    11.9      M    M
 25000  -33.5 -28.3   300   66   34   8.0   4.4   20.9  69.5    11.5      M    M
 24000  -31.0 -23.8   300   66   34   8.1   4.4   20.3  68.6    11.2      M    M
 23000  -28.6 -19.5   300   65   33   8.1   4.5   19.7  67.4    10.8      M    M
 22000  -26.2 -15.2   300   63   33   8.1   4.5   19.1  66.4    10.4      M    M
 21000  -23.8 -10.8   300   62   32   7.7   4.2   18.6  65.5    10.1      M    M
 20000  -21.6  -6.9   300   59   30   7.4   4.0   17.7  63.8     9.4      M    M
 19500  -20.5  -4.9   300   58   30   7.4   4.0   17.3  63.1     9.1      M    M
 19000  -19.4  -2.9   300   56   29   7.4   4.0   16.9  62.4     8.8      M    M
 18500  -18.3  -0.9   300   55   28   7.2   4.0   16.5  61.8     8.5      M    M
 18000  -17.3   0.9   300   54   28   6.8   3.8   16.0  60.9     8.1      M    M
 17500  -16.3   2.7   300   52   27   6.9   3.8   15.6  60.0     7.7      M    M
 17000  -15.3   4.5   300   51   26   6.3   3.4   15.0  59.1     7.3      M    M
 16500  -14.4   6.1   300   51   26   6.3   3.5   14.4  58.0     6.8      M    M
 16000  -13.0   8.6   300   50   26   6.2   3.4   13.6  56.4     6.0      M    M
 15500  -12.1  10.2   300   49   25   6.2   3.4   13.0  55.4     5.5      M    M
 15000  -11.1  12.0   300   48   25   6.5   3.6   12.4  54.4     5.0      M    M
 14500  -10.2  13.6   300   48   24   6.5   3.6   11.9  53.4     4.5      M    M
 14000   -9.2  15.4   300   47   24   6.5   3.6   11.4  52.5     4.0      M    M
 13500   -8.2  17.2   300   47   24   6.6   3.6   10.9  51.5     3.6      M    M
 13000   -7.3  18.9   300   48   25   7.7   4.2   10.4  50.7     3.1      M    M
 12500   -6.0  21.2   300   46   24   9.0   4.9   10.2  50.3     2.9      M    M
 12000   -5.0  23.0   300   43   22   5.1   2.8    9.6  49.3     2.4      M    M
 11750   -4.5  23.9   300   41   21   7.2   4.0    9.4  48.9     2.2      M    M
 11500   -4.0  24.8   300   39   20   6.3   3.5    9.1  48.5     2.0      M    M
 11250   -3.5  25.7   300   36   19   7.8   4.3    8.9  48.0     1.8      M    M
 11000   -2.9  26.8   300   34   18   6.7   3.7    8.8  47.8     1.6      M    M
 10750   -2.5  27.5   300   31   16   4.7   2.6    8.4  47.1     1.3      M    M
 10500   -2.1  28.2   295   29   15   5.3   2.9    8.1  46.5     1.0      M    M
 10250   -1.7  28.9   295   26   14   5.0   2.8    7.7  45.9     0.6      M    M
 10000   -1.3  29.7   295   24   12   6.6   3.6    7.4  45.3     0.3      M    M
  9750   -0.7  30.7   295   22   11   8.7   4.8    7.2  45.0     0.2      M    M
  9500   -0.1  31.8   290   20   10   8.7   4.8    7.2  44.9     0.1      M    M
  9250    0.6  33.1   290   18    9   9.6   5.3    7.1  44.8     0.0      M    M
  9000    1.4  34.5   290   17    9  13.2   7.3    7.2  45.0     0.1      M    M
  8750    2.4  36.3   290   17    9  11.9   6.5    7.5  45.5     0.4      M    M
  8500    3.2  37.8   290   17    9  14.3   7.9    7.6  45.7     0.5      M    M
  8250    4.1  39.4   290   17    9  -0.1  -0.1    7.8  46.0     0.6      M    M
  8000    3.1  37.6   285   17    9 -20.5 -11.2    6.0  42.8    -1.1     69  0.4
  7750    1.7  35.1   280   16    8 -14.3  -7.8    3.9  38.9    -3.2    102  0.5
  7500    0.8  33.4   275   14    7 -12.2  -6.7    2.3  36.1    -4.8    122  0.6
  7250   -0.7  30.7   270   11    5 -30.5 -16.8    0.2  32.4    -6.9    159  0.8
  7000   -3.8  25.2   270    8    4 -51.3 -28.1   -3.2  26.3   -10.3    246  1.3
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/09/2016 at 0800 MST          |       12/09/2016 at 1100 MST
                                           |
K index... +12.5  LI... +1.5               | K index... +9.2  LI... +2.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -61.2 -78.2  290  49 25   0.7   0.4 | -60.9 -77.6  290  44 22   1.3   0.7
 45000 -60.2 -76.4  290  73 38   0.8   0.4 | -59.0 -74.2  290  69 36   1.3   0.7
 40000 -62.8 -81.0  300  63 33  -1.9  -1.1 | -64.1 -83.4  300  70 36  -3.6  -2.0
 38000 -62.5 -80.5  300  60 31   5.0   2.7 | -63.6 -82.5  305  71 36   6.5   3.6
 36000 -59.5 -75.1  305  61 31   5.0   2.7 | -59.7 -75.5  305  71 37   6.5   3.6
 34000 -56.4 -69.5  305  61 31   7.3   4.0 | -55.7 -68.3  305  71 37   8.7   4.8
 32000 -50.8 -59.4  300  55 28   8.3   4.5 | -50.6 -59.1  305  68 35   8.4   4.6
 30000 -45.9 -50.6  295  51 26   8.1   4.4 | -45.6 -50.1  305  65 33   7.8   4.3
 29000 -43.4 -46.1  295  51 26   8.1   4.5 | -43.3 -45.9  305  63 32   7.9   4.3
 28000 -41.0 -41.8  295  52 27   8.1   4.5 | -40.3 -40.5  305  60 31   7.9   4.3
 27000 -38.5 -37.3  295  52 27   8.0   4.4 | -37.9 -36.2  305  58 30   7.9   4.3
 26000 -36.2 -33.2  295  53 27   7.7   4.2 | -35.6 -32.1  305  58 30   7.9   4.3
 25000 -33.9 -29.0  300  54 28   7.7   4.2 | -33.2 -27.8  305  57 29   7.9   4.3
 24000 -31.6 -24.9  300  55 28   7.7   4.2 | -30.8 -23.4  305  57 29   7.5   4.1
 23000 -29.2 -20.6  300  55 28   8.0   4.4 | -28.7 -19.7  305  55 28   7.1   3.9
 22000 -26.9 -16.4  305  55 28   8.0   4.4 | -26.6 -15.9  305  53 27   7.1   3.9
 21000 -24.5 -12.1  305  55 28   7.1   3.9 | -24.5 -12.1  305  50 26   7.0   3.9
 20000 -22.6  -8.7  305  52 27   6.5   3.6 | -22.4  -8.3  305  46 24   7.0   3.9
 19500 -21.6  -6.9  305  50 26   6.5   3.6 | -21.4  -6.5  305  44 22   7.0   3.9
 19000 -20.6  -5.1  305  49 25   6.5   3.6 | -20.3  -4.5  300  41 21   7.0   3.9
 18500 -19.7  -3.5  305  47 24   6.5   3.6 | -19.3  -2.7  300  39 20   7.2   4.0
 18000 -18.7  -1.7  305  45 23   6.4   3.5 | -18.2  -0.8  295  35 18   7.3   4.0
 17500 -17.8  -0.0  305  43 22   6.4   3.5 | -17.1   1.2  285  31 16   7.3   4.0
 17000 -16.8   1.8  305  41 21   6.8   3.7 | -16.1   3.0  285  28 14   7.0   3.9
 16500 -15.8   3.6  305  37 19   6.8   3.7 | -15.0   5.0  285  25 13   7.0   3.8
 16000 -14.2   6.4  310  34 17   7.7   4.2 | -13.9   7.0  290  23 12   7.9   4.3
 15500 -13.1   8.4  310  32 17   7.6   4.2 | -12.8   9.0  290  24 12   7.9   4.3
 15000 -11.9  10.6  315  31 16   8.6   4.7 | -11.6  11.1  295  25 13   7.2   4.0
 14500 -10.6  12.9  320  31 16   8.6   4.7 | -10.6  12.9  300  26 13   6.9   3.8
 14000  -9.4  15.1  325  31 16   8.9   4.9 |  -9.0  15.8  305  28 14   7.6   4.2
 13500  -8.0  17.6  325  33 17   9.0   4.9 |  -7.9  17.8  305  30 15   7.6   4.2
 13000  -6.7  19.9  320  35 18   8.8   4.8 |  -6.8  19.8  310  31 16   7.3   4.0
 12500  -5.4  22.3  320  34 17   8.9   4.9 |  -5.8  21.6  315  30 15   7.5   4.1
 12000  -4.2  24.4  320  34 17   6.8   3.7 |  -4.8  23.4  315  31 16   6.6   3.6
 11750  -3.7  25.3  315  34 18   7.1   3.9 |  -4.3  24.3  315  31 16   7.9   4.4
 11500  -3.2  26.2  315  35 18   7.0   3.8 |  -3.7  25.3  320  31 16   7.8   4.3
 11250  -2.7  27.1  310  35 18   7.1   3.9 |  -3.1  26.4  320  31 16   7.1   3.9
 11000  -2.2  28.0  310  34 17   6.3   3.4 |  -2.6  27.3  320  31 16   6.7   3.7
 10750  -1.7  28.9  310  33 17   5.6   3.1 |  -2.1  28.2  320  30 15   7.3   4.0
 10500  -1.3  29.7  305  33 17   5.8   3.2 |  -1.6  29.1  320  29 15   7.4   4.0
 10250  -0.9  30.4  305  32 16   5.9   3.2 |  -1.1  30.0  320  28 14   6.4   3.5
 10000  -0.4  31.3  300  31 16   6.3   3.4 |  -0.7  30.7  320  26 14   5.4   3.0
  9750   0.0  32.0  300  29 15   6.1   3.4 |  -0.2  31.6  320  25 13   6.3   3.5
  9500   0.5  32.9  300  27 14   5.8   3.2 |   0.3  32.5  320  23 12   7.0   3.8
  9250   0.9  33.6  295  25 13   6.1   3.4 |   0.8  33.4  320  22 11   6.0   3.3
  9000   1.4  34.5  295  23 12   7.3   4.0 |   1.2  34.2  320  20 11   5.1   2.8
  8750   1.9  35.4  295  22 11   6.1   3.3 |   1.5  34.7  320  19 10   5.3   2.9
  8500   2.3  36.1  295  21 11   6.8   3.7 |   1.9  35.4  320  18  9   5.1   2.8
  8250   2.8  37.0  290  19 10   0.5   0.3 |   2.3  36.1  320  16  8   4.0   2.2
  8000   2.3  36.1  290  18  9  -9.6  -5.3 |   2.5  36.5  320  15  8   1.7   0.9
  7750   1.8  35.2  285  16  8  -1.0  -0.5 |   2.7  36.9  320  14  7   7.2   3.9
  7500   2.0  35.6  280  14  7  -0.7  -0.4 |   3.3  37.9  315  12  6   3.8   2.1
  7250   0.9  33.6  280  11  6 -29.6 -16.3 |   2.9  37.2  310  10  5  -8.4  -4.6
  7000  -2.4  27.7  280   9  5 -55.5 -30.4 |   2.3  36.1  310   7  4  -5.3  -2.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/09/2016 at 1400 MST          |       12/09/2016 at 1700 MST
                                           |
K index... +7.5  LI... +2.9                | K index... +7.5  LI... +5.1
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.3
                                           |
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 -61.1 -78.0  290  52 27  -0.2  -0.1 | -61.9 -79.4  290  54 28  -0.8  -0.5
 45000 -61.4 -78.5  285  78 40  -0.1  -0.1 | -63.2 -81.8  285  76 39  -0.8  -0.4
 40000 -65.5 -85.9  300  76 39  -2.9  -1.6 | -65.1 -85.2  290  69 36  -1.4  -0.7
 38000 -64.9 -84.8  305  75 39   7.3   4.0 | -64.1 -83.4  295  68 35   6.4   3.5
 36000 -60.5 -76.9  295  75 38   7.2   4.0 | -60.2 -76.4  290  68 35   6.4   3.5
 34000 -55.5 -67.9  290  73 38   8.7   4.8 | -55.6 -68.1  290  68 35   8.4   4.6
 32000 -50.2 -58.4  300  67 35   8.7   4.8 | -50.6 -59.1  290  63 33   8.4   4.6
 30000 -45.0 -49.0  305  63 32   8.2   4.5 | -45.4 -49.7  290  59 31   9.1   5.0
 29000 -42.6 -44.7  305  63 32   8.2   4.5 | -42.7 -44.9  290  59 30   9.1   5.0
 28000 -40.1 -40.2  305  62 32   8.2   4.5 | -40.0 -40.0  295  58 30   9.1   5.0
 27000 -37.6 -35.7  310  62 32   8.2   4.5 | -37.3 -35.1  295  57 30   8.7   4.8
 26000 -35.2 -31.4  310  59 30   8.2   4.5 | -34.7 -30.5  295  56 29   8.5   4.7
 25000 -32.7 -26.9  305  56 29   8.2   4.5 | -32.2 -26.0  300  54 28   8.5   4.7
 24000 -30.3 -22.5  305  53 27   8.0   4.4 | -29.6 -21.3  300  53 27   8.6   4.7
 23000 -27.9 -18.2  305  51 26   7.7   4.2 | -27.1 -16.8  300  51 26   8.6   4.7
 22000 -25.6 -14.1  310  48 25   7.7   4.2 | -24.5 -12.1  300  50 26   8.7   4.7
 21000 -23.3  -9.9  310  45 23   7.0   3.8 | -21.9  -7.4  295  48 25   7.5   4.1
 20000 -21.3  -6.3  305  41 21   6.7   3.7 | -19.7  -3.5  295  45 23   7.3   4.0
 19500 -20.3  -4.5  305  38 20   6.8   3.7 | -18.6  -1.5  295  44 22   7.3   4.0
 19000 -19.3  -2.7  305  36 19   6.8   3.7 | -17.6   0.3  295  42 22   7.3   4.0
 18500 -18.3  -0.9  305  34 17   7.1   3.9 | -16.5   2.3  295  41 21   6.6   3.6
 18000 -17.2   1.0  300  31 16   7.3   4.0 | -15.6   3.9  295  40 20   6.1   3.3
 17500 -16.1   3.0  300  29 15   7.3   4.0 | -14.7   5.5  295  38 20   6.0   3.3
 17000 -14.9   5.2  295  26 13   8.9   4.9 | -13.9   7.0  295  36 18   4.9   2.7
 16500 -12.9   8.8  280  22 11   8.4   4.6 | -13.2   8.2  295  32 16   5.0   2.8
 16000 -11.8  10.8  285  23 12   6.9   3.8 | -12.1  10.2  295  30 15   4.5   2.5
 15500 -10.7  12.7  295  26 14   7.2   4.0 | -11.5  11.3  300  30 16   4.6   2.5
 15000  -9.9  14.2  295  29 15   4.5   2.5 | -10.9  12.4  300  32 16   3.7   2.1
 14500  -9.2  15.4  295  32 16   4.9   2.7 | -10.3  13.5  300  33 17   3.8   2.1
 14000  -8.5  16.7  295  34 18   3.7   2.0 |  -9.7  14.5  300  33 17   4.5   2.5
 13500  -8.0  17.6  295  37 19   3.5   1.9 |  -9.0  15.8  300  31 16   4.5   2.5
 13000  -7.5  18.5  295  39 20   5.4   3.0 |  -8.3  17.1  300  29 15   6.4   3.5
 12500  -6.6  20.1  295  35 18   6.2   3.4 |  -7.3  18.9  300  25 13   7.1   3.9
 12000  -5.8  21.6  295  30 16   6.7   3.7 |  -6.4  20.5  295  22 11   7.3   4.0
 11750  -5.2  22.6  295  28 14   8.7   4.8 |  -5.7  21.7  295  20 10   9.1   5.0
 11500  -4.6  23.7  295  25 13   8.7   4.8 |  -5.1  22.8  295  18  9   8.9   4.9
 11250  -4.0  24.8  295  23 12   6.7   3.7 |  -4.4  24.1  295  17  9   7.9   4.3
 11000  -3.6  25.5  290  21 11   6.9   3.8 |  -3.9  25.0  290  16  8   8.5   4.7
 10750  -3.0  26.6  290  19 10   9.0   5.0 |  -3.2  26.2  290  14  7  10.0   5.5
 10500  -2.3  27.9  290  17  9   8.7   4.8 |  -2.4  27.7  290  13  6  10.0   5.5
 10250  -1.7  28.9  285  15  8   7.8   4.3 |  -1.7  28.9  285  11  6   8.3   4.6
 10000  -1.2  29.8  285  13  7   6.4   3.5 |  -1.2  29.8  280  10  5   6.3   3.5
  9750  -0.7  30.7  280  11  6   7.7   4.2 |  -0.7  30.7  275   8  4   8.3   4.6
  9500  -0.0  32.0  275   9  5   8.9   4.9 |   0.0  32.0  265   7  4  10.2   5.6
  9250   0.6  33.1  265   7  4   7.9   4.3 |   0.7  33.3  255   6  3   7.9   4.3
  9000   1.1  34.0  260   6  3   6.8   3.7 |   1.2  34.2  245   6  3   5.4   3.0
  8750   1.7  35.1  255   5  2   7.2   4.0 |   1.6  34.9  235   5  3   6.6   3.6
  8500   2.2  36.0  235   4  2   7.7   4.2 |   2.2  36.0  215   6  3   7.2   4.0
  8250   2.8  37.0  205   3  2   6.1   3.3 |   2.6  36.7  200   6  3   4.3   2.4
  8000   3.1  37.6  195   3  2   3.9   2.2 |   2.8  37.0  195   6  3   1.0   0.5
  7750   3.5  38.3  180   3  2   7.3   4.0 |   2.9  37.2  190   6  3   6.5   3.5
  7500   4.0  39.2  160   3  2   4.7   2.6 |   3.4  38.1  180   6  3   1.0   0.5
  7250   3.9  39.0  155   3  2  -4.4  -2.4 |   2.8  37.0  175   6  3 -14.3  -7.8
  7000   3.4  38.1  155   3  1  -5.0  -2.7 |   1.6  34.9  175   4  2 -12.8  -7.0
  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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