Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 101312
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0612 MST Saturday, December 10, 2016

This forecast is for Saturday, December 10, 2016:

If the trigger temperature of 51.0 F/10.6 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 222 ft/min (1.1 m/s)
   Maximum height of thermals.................. 10744 ft MSL (3986 ft AGL)

Forecast maximum temperature................... 51.0 F/11.0 C
Time of trigger temperature.................... 1415 MST
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8555 ft MSL (1797 ft AGL)
Thermal soaring outlook for Sunday 12/11....... Fair

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

Remarks...

Sunrise/Sunset.................... 07:07:13 / 16:37:03 MST
Total possible sunshine........... 9 hr 29 min 50 sec (569 min 50 sec)
Altitude of sun at 11:52:12 MST... 28.12 degrees

Upper air data from numerical model forecast valid on 12/10/2016 at 0500 MST

Freezing level.................. 7030 ft MSL (272 ft AGL)
Additional freezing level....... 10671 ft MSL (3913 ft AGL)
Convective condensation level... 16766 ft MSL (10008 ft AGL)
Lifted condensation level....... 14072 ft MSL (7314 ft AGL)
Lifted index.................... +5.6
K index......................... +5.0

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  -62.9 -81.2   285   62   32  -1.0  -0.5      M     M       M      M    M
 45000  -64.3 -83.7   285   70   36  -1.0  -0.5      M     M       M      M    M
 40000  -65.6 -86.1   295   67   34  -0.8  -0.5      M     M       M      M    M
 38000  -64.1 -83.4   300   66   34   6.8   3.7      M     M       M      M    M
 36000  -60.0 -76.0   300   66   34   6.8   3.7      M     M       M      M    M
 34000  -55.0 -67.0   300   63   32   9.1   5.0      M     M       M      M    M
 32000  -49.5 -57.1   295   56   29   9.2   5.0      M     M       M      M    M
 30000  -44.1 -47.4   295   49   25   8.8   4.8   25.3  77.5    11.3      M    M
 29000  -41.4 -42.5   295   46   24   8.8   4.8   24.8  76.7    11.1      M    M
 28000  -38.8 -37.8   295   44   22   8.8   4.8   24.5  76.1    11.0      M    M
 27000  -36.1 -33.0   295   41   21   9.4   5.2   24.3  75.7    10.9      M    M
 26000  -33.3 -27.9   295   37   19   9.6   5.2   24.1  75.4    10.9      M    M
 25000  -30.4 -22.7   290   33   17   9.6   5.2   24.0  75.3    11.0      M    M
 24000  -27.5 -17.5   285   29   15   9.0   4.9   24.1  75.3    11.1      M    M
 23000  -25.0 -13.0   290   32   16   8.4   4.6   23.5  74.3    10.8      M    M
 22000  -22.5  -8.5   295   34   18   8.4   4.6   23.0  73.4    10.5      M    M
 21000  -20.1  -4.2   295   37   19   6.4   3.5   22.5  72.4    10.1      M    M
 20000  -18.3  -0.9   300   41   21   6.1   3.3   21.1  70.0     9.1      M    M
 19500  -17.4   0.7   300   42   22   6.1   3.3   20.5  68.9     8.6      M    M
 19000  -16.5   2.3   300   44   23   6.1   3.3   19.9  67.8     8.1      M    M
 18500  -15.6   3.9   300   46   24   5.9   3.2   19.3  66.8     7.6      M    M
 18000  -14.7   5.5   300   47   24   5.7   3.1   18.6  65.5     7.0      M    M
 17500  -13.9   7.0   300   49   25   5.7   3.1   17.9  64.3     6.4      M    M
 17000  -13.0   8.6   300   50   26   6.4   3.5   17.3  63.1     5.9      M    M
 16500  -11.5  11.3   300   52   27   6.4   3.5   16.5  61.6     5.2      M    M
 16000  -10.6  12.9   300   52   27   6.7   3.7   15.9  60.7     4.7      M    M
 15500   -9.6  14.7   300   52   27   6.6   3.6   15.4  59.8     4.3      M    M
 15000   -8.5  16.7   300   51   26   7.0   3.8   14.9  58.9     3.9      M    M
 14500   -7.5  18.5   300   49   25   7.0   3.8   14.5  58.1     3.4      M    M
 14000   -6.5  20.3   300   48   25   7.0   3.8   14.0  57.3     3.0      M    M
 13500   -5.4  22.3   295   47   24   7.0   3.8   13.6  56.5     2.6      M    M
 13000   -4.4  24.1   295   45   23   7.3   4.0   13.2  55.7     2.2      M    M
 12500   -3.3  26.1   295   44   22   7.9   4.3   12.8  55.0     1.8      M    M
 12000   -2.5  27.5   295   40   20   5.1   2.8   12.2  53.9     1.2      M    M
 11750   -2.0  28.4   295   38   20   6.9   3.8   11.9  53.5     1.0      M    M
 11500   -1.5  29.3   295   36   19   6.4   3.5   11.7  53.0     0.7      M    M
 11250   -1.0  30.2   295   34   18   6.7   3.7   11.4  52.6     0.5      M    M
 11000   -0.5  31.1   295   32   16   6.7   3.7   11.2  52.1     0.2      M    M
 10750   -0.1  31.8   295   30   15   6.4   3.5   10.9  51.7    -0.0    318  1.6
 10500    0.4  32.7   295   28   14   6.5   3.6   10.7  51.2    -0.3    297  1.5
 10250    0.9  33.6   295   26   13   6.3   3.5   10.4  50.8    -0.6    275  1.4
 10000    1.3  34.3   290   25   13   5.3   2.9   10.1  50.2    -0.9    255  1.3
  9750    1.7  35.1   290   23   12   5.2   2.8    9.8  49.6    -1.2    237  1.2
  9500    2.1  35.8   285   21   11   5.6   3.1    9.4  49.0    -1.6    217  1.1
  9250    2.5  36.5   280   19   10   5.3   2.9    9.1  48.4    -1.9    198  1.0
  9000    2.8  37.0   280   17    9   4.9   2.7    8.7  47.7    -2.3    180  0.9
  8750    3.2  37.8   270   15    8   4.2   2.3    8.4  47.0    -2.7    162  0.8
  8500    3.5  38.3   265   14    7   4.7   2.6    7.9  46.3    -3.1    145  0.7
  8250    3.8  38.8   255   12    6   1.8   1.0    7.5  45.5    -3.6    129  0.7
  8000    3.7  38.7   250   11    6  -4.4  -2.4    6.6  43.9    -4.4    125  0.6
  7750    3.5  38.3   250   10    5   3.7   2.0    5.7  42.3    -5.3    123  0.6
  7500    4.0  39.2   245    9    5   4.4   2.4    5.5  42.0    -5.5     99  0.5
  7250    3.3  37.9   250    8    4 -29.5 -16.2    4.2  39.6    -6.9    114  0.6
  7000   -0.4  31.3   260    8    4 -63.5 -34.9    0.3  32.6   -10.7    217  1.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           12/10/2016 at 0800 MST          |       12/10/2016 at 1100 MST
                                           |
K index... +1.4  LI... +5.0                | K index... +0.6  LI... +5.9
CAPE... 0.0  CIN... -1.1                   | CAPE... 0.0  CIN... M
                                           |
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 -62.8 -81.0  290  65 33  -2.2  -1.2 | -63.8 -82.8  285  64 33  -3.3  -1.8
 45000 -66.2 -87.2  290  83 43  -2.4  -1.3 | -68.8 -91.8  285  77 39  -3.9  -2.2
 40000 -66.3 -87.3  305  67 34   0.1   0.1 | -65.9 -86.6  305  71 36   2.2   1.2
 38000 -64.3 -83.7  305  62 32   7.0   3.8 | -63.4 -82.1  305  70 36   6.2   3.4
 36000 -60.1 -76.2  300  58 30   7.0   3.8 | -59.6 -75.3  300  70 36   6.2   3.4
 34000 -55.6 -68.1  290  55 29  10.0   5.5 | -55.5 -67.9  295  69 35   9.7   5.3
 32000 -48.9 -56.0  285  54 28   9.8   5.4 | -49.0 -56.2  290  62 32   9.6   5.3
 30000 -43.2 -45.8  285  52 27   8.9   4.9 | -43.3 -45.9  290  57 30   9.6   5.3
 29000 -40.5 -40.9  285  52 27   8.9   4.9 | -40.4 -40.7  285  56 29   9.6   5.3
 28000 -37.9 -36.2  285  52 27   8.9   4.9 | -37.5 -35.5  285  55 28   9.6   5.3
 27000 -35.2 -31.4  280  51 26   8.3   4.5 | -34.6 -30.3  280  53 27   9.3   5.1
 26000 -32.8 -27.0  280  48 25   8.2   4.5 | -31.8 -25.2  275  50 26   9.3   5.1
 25000 -30.3 -22.5  280  46 24   8.2   4.5 | -29.0 -20.2  270  48 25   9.3   5.1
 24000 -27.9 -18.2  280  43 22   8.5   4.7 | -26.3 -15.3  265  46 24   9.2   5.1
 23000 -25.2 -13.4  275  39 20   8.8   4.8 | -23.5 -10.3  265  43 22   9.2   5.1
 22000 -22.6  -8.7  275  34 18   8.8   4.8 | -20.7  -5.3  265  40 21   9.2   5.1
 21000 -20.0  -4.0  270  32 16   7.6   4.2 | -18.1  -0.6  265  38 20   7.5   4.1
 20000 -17.8  -0.0  280  36 19   7.5   4.1 | -15.9   3.4  275  41 21   7.3   4.0
 19500 -16.7   1.9  280  39 20   7.5   4.1 | -14.8   5.4  280  42 22   7.4   4.0
 19000 -15.6   3.9  285  42 21   7.5   4.1 | -13.7   7.3  285  44 23   7.3   4.0
 18500 -14.5   5.9  285  44 23   7.3   4.0 | -12.6   9.3  285  46 24   6.8   3.8
 18000 -13.4   7.9  290  47 24   7.1   3.9 | -11.7  10.9  290  49 25   6.4   3.5
 17500 -12.3   9.9  290  50 26   7.1   3.9 | -10.8  12.6  290  52 27   6.4   3.5
 17000 -11.4  11.5  290  52 27   6.1   3.4 |  -9.8  14.4  295  54 28   6.3   3.5
 16500 -10.4  13.3  290  54 28   6.2   3.4 |  -8.9  16.0  295  57 29   6.4   3.5
 16000  -9.5  14.9  290  56 29   6.4   3.5 |  -7.6  18.3  295  59 31   5.1   2.8
 15500  -8.0  17.6  290  58 30   6.5   3.5 |  -6.8  19.8  295  61 31   5.2   2.9
 15000  -7.1  19.2  295  58 30   5.8   3.2 |  -6.0  21.2  295  62 32   5.3   2.9
 14500  -6.2  20.8  295  57 30   5.8   3.2 |  -5.3  22.5  295  62 32   5.3   2.9
 14000  -5.4  22.3  295  56 29   6.0   3.3 |  -4.5  23.9  295  63 32   5.3   2.9
 13500  -4.5  23.9  295  54 28   6.0   3.3 |  -3.7  25.3  295  61 31   5.4   2.9
 13000  -3.6  25.5  295  52 27   5.8   3.2 |  -2.9  26.8  295  60 31   5.5   3.0
 12500  -2.7  27.1  295  50 26   5.8   3.2 |  -2.0  28.4  295  56 29   5.7   3.1
 12000  -2.0  28.4  300  46 24   5.3   2.9 |  -1.3  29.7  295  52 27   4.5   2.5
 11750  -1.6  29.1  300  44 23   6.0   3.3 |  -0.9  30.4  295  49 25   5.4   3.0
 11500  -1.1  30.0  300  42 21   6.0   3.3 |  -0.5  31.1  295  46 24   5.4   3.0
 11250  -0.7  30.7  300  39 20   5.5   3.0 |  -0.1  31.8  295  43 22   5.4   2.9
 11000  -0.4  31.3  300  37 19   5.5   3.0 |   0.3  32.5  295  40 21   4.9   2.7
 10750   0.0  32.0  300  34 18   6.0   3.3 |   0.6  33.1  295  37 19   4.5   2.5
 10500   0.5  32.9  295  32 16   5.9   3.2 |   0.9  33.6  295  34 18   4.6   2.5
 10250   0.9  33.6  295  29 15   6.0   3.3 |   1.3  34.3  295  31 16   4.7   2.6
 10000   1.3  34.3  295  27 14   5.6   3.0 |   1.6  34.9  295  29 15   4.5   2.5
  9750   1.7  35.1  295  25 13   5.1   2.8 |   1.9  35.4  290  26 14   3.0   1.7
  9500   2.0  35.6  290  23 12   5.2   2.9 |   2.0  35.6  290  24 12   2.2   1.2
  9250   2.4  36.3  290  21 11   5.1   2.8 |   2.1  35.8  290  21 11   2.3   1.3
  9000   2.8  37.0  285  19 10   5.2   2.9 |   2.3  36.1  285  19 10   3.8   2.1
  8750   3.1  37.6  280  18  9   3.7   2.0 |   2.7  36.9  280  17  9   5.4   3.0
  8500   3.3  37.9  270  16  8   3.1   1.7 |   3.0  37.4  275  15  8   5.6   3.1
  8250   3.6  38.5  265  15  8   1.5   0.8 |   3.4  38.1  265  13  7   4.8   2.6
  8000   3.5  38.3  255  14  7  -3.4  -1.9 |   3.6  38.5  255  11  6   1.1   0.6
  7750   3.3  37.9  250  12  6   0.7   0.4 |   3.7  38.7  245  10  5   2.4   1.3
  7500   3.7  38.7  245  11  5   8.6   4.7 |   4.0  39.2  235   9  4   7.1   3.9
  7250   3.7  38.7  240   9  5 -19.4 -10.6 |   4.5  40.1  220   8  4   4.4   2.4
  7000   0.3  32.5  250   7  4 -67.4 -37.0 |   4.6  40.3  220   7  4  -1.6  -0.9
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           12/10/2016 at 1400 MST          |       12/10/2016 at 1700 MST
                                           |
K index... -5.1  LI... +5.3                | K index... +9.3  LI... +3.6
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.4
                                           |
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 -64.6 -84.3  290  68 35  -2.0  -1.1 | -65.3 -85.5  290  73 37  -2.3  -1.2
 45000 -67.8 -90.0  285  77 40  -1.7  -0.9 | -68.7 -91.7  290  82 42  -2.4  -1.3
 40000 -65.6 -86.1  305  64 33   1.6   0.9 | -66.1 -87.0  295  64 33   2.0   1.1
 38000 -63.0 -81.4  305  60 31   6.7   3.7 | -63.0 -81.4  295  61 32   7.8   4.3
 36000 -59.0 -74.2  290  59 30   6.7   3.7 | -58.3 -72.9  285  63 32   7.9   4.3
 34000 -54.5 -66.1  280  59 31   9.8   5.4 | -53.3 -63.9  280  64 33   9.2   5.0
 32000 -48.6 -55.5  285  58 30   9.8   5.4 | -47.8 -54.0  275  61 31   9.2   5.1
 30000 -42.8 -45.0  285  55 28   9.0   5.0 | -42.2 -44.0  275  57 29   9.3   5.1
 29000 -40.1 -40.2  280  50 26   9.1   5.0 | -39.4 -38.9  275  53 27   9.4   5.1
 28000 -36.7 -34.1  275  44 22   9.1   5.0 | -36.6 -33.9  270  49 25   9.4   5.1
 27000 -34.0 -29.2  270  39 20   9.0   4.9 | -33.8 -28.8  270  45 23   9.1   5.0
 26000 -31.3 -24.3  265  36 19   9.0   4.9 | -30.5 -22.9  265  44 23   8.8   4.8
 25000 -28.6 -19.5  260  34 17   9.0   4.9 | -27.9 -18.2  260  43 22   8.8   4.8
 24000 -25.9 -14.6  255  32 16   9.1   5.0 | -25.3 -13.5  260  42 22   8.8   4.8
 23000 -23.2  -9.8  260  33 17   9.1   5.0 | -22.6  -8.7  260  45 23   8.8   4.8
 22000 -20.4  -4.7  260  34 18   9.1   5.0 | -20.0  -4.0  265  47 24   8.8   4.8
 21000 -17.8  -0.0  265  36 19   7.8   4.3 | -17.5   0.5  265  50 26   7.4   4.0
 20000 -15.5   4.1  270  41 21   7.7   4.2 | -15.3   4.5  270  52 27   7.3   4.0
 19500 -14.3   6.3  275  43 22   7.7   4.2 | -14.2   6.4  270  54 28   7.3   4.0
 19000 -13.2   8.2  275  45 23   7.7   4.2 | -13.1   8.4  275  55 28   7.3   4.0
 18500 -12.0  10.4  280  47 24   7.1   3.9 | -12.1  10.2  275  57 29   7.0   3.9
 18000 -11.1  12.0  280  50 26   6.6   3.6 | -11.1  12.0  275  49 25   6.8   3.7
 17500 -10.1  13.8  285  52 27   6.6   3.6 | -10.1  13.8  275  42 21   6.9   3.8
 17000  -9.1  15.6  285  54 28   6.5   3.5 |  -9.1  15.6  275  39 20   5.7   3.1
 16500  -8.2  17.2  285  57 29   6.5   3.6 |  -8.3  17.1  285  42 21   5.8   3.2
 16000  -7.2  19.0  285  59 30   5.9   3.2 |  -7.5  18.5  290  44 23   5.3   2.9
 15500  -6.4  20.5  285  61 32   5.7   3.1 |  -6.8  19.8  290  48 25   5.1   2.8
 15000  -5.6  21.9  285  64 33   5.6   3.1 |  -6.0  21.2  295  51 27   5.2   2.9
 14500  -4.7  23.5  285  65 34   5.4   2.9 |  -5.3  22.5  295  54 28   5.6   3.1
 14000  -3.9  25.0  285  67 35   5.4   3.0 |  -4.4  24.1  295  56 29   5.7   3.1
 13500  -3.0  26.6  280  67 34   6.5   3.6 |  -3.6  25.5  295  58 30   5.9   3.2
 13000  -2.0  28.4  280  65 33   6.4   3.5 |  -2.8  27.0  295  60 31   5.9   3.2
 12500  -0.9  30.4  280  62 32   7.7   4.2 |  -1.9  28.6  295  60 31   6.5   3.5
 12000   0.1  32.2  280  59 30   5.4   3.0 |  -1.1  30.0  295  58 30   4.5   2.5
 11750   0.5  32.9  280  57 29   5.0   2.8 |  -0.7  30.7  295  57 30   4.7   2.6
 11500   0.9  33.6  280  54 28   4.9   2.7 |  -0.3  31.5  295  55 28   5.5   3.0
 11250   1.2  34.2  280  51 26   5.1   2.8 |   0.1  32.2  290  53 27   5.6   3.1
 11000   1.6  34.9  275  48 25   4.5   2.5 |   0.5  32.9  290  50 26   5.4   3.0
 10750   1.8  35.2  275  46 24   3.5   1.9 |   0.9  33.6  290  48 25   4.9   2.7
 10500   2.1  35.8  275  43 22   3.3   1.8 |   1.3  34.3  290  45 23   4.5   2.5
 10250   2.5  36.5  270  36 19   3.4   1.9 |   1.6  34.9  290  42 22   4.5   2.4
 10000   2.7  36.9  265  33 17   4.9   2.7 |   2.3  36.1  285  36 19   4.4   2.4
  9750   3.1  37.6  265  30 15   5.2   2.9 |   2.7  36.9  285  34 17   4.6   2.5
  9500   3.4  38.1  260  27 14   4.5   2.5 |   3.0  37.4  285  30 16   4.8   2.6
  9250   3.7  38.7  255  24 12   4.7   2.6 |   3.3  37.9  280  27 14   4.6   2.5
  9000   3.9  39.0  250  21 11   3.7   2.0 |   3.7  38.7  275  24 12   5.2   2.9
  8750   4.2  39.6  240  20 10   5.9   3.2 |   4.1  39.4  270  22 11   6.1   3.4
  8500   4.8  40.6  230  18  9   8.2   4.5 |   4.5  40.1  265  19 10   6.4   3.5
  8250   5.3  41.5  225  17  9   7.3   4.0 |   5.0  41.0  260  17  9   5.7   3.2
  8000   5.8  42.4  215  16  8   6.2   3.4 |   5.3  41.5  255  15  8   3.3   1.8
  7750   6.2  43.2  210  15  7   4.6   2.5 |   5.3  41.5  245  13  7  -7.5  -4.1
  7500   6.5  43.7  205  12  6   3.7   2.0 |   4.1  39.4  235   9  5 -21.6 -11.9
  7250   6.7  44.1  195   9  5   5.0   2.7 |   3.0  37.4  220   6  3   2.6   1.4
  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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