Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 271156
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0456 MST Sunday, November 27, 2016

This forecast is for Sunday, November 27, 2016:

If the trigger temperature of 50.2 F/10.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8160 ft MSL (990 ft AGL)

Forecast maximum temperature................... 43.0 F/6.6 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................. 7417 ft MSL (247 ft AGL)
Thermal soaring outlook for Monday 11/28....... Excellent

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

Remarks...

Sunrise/Sunset.................... 06:55:19 / 16:38:22 MST
Total possible sunshine........... 9 hr 43 min 2 sec (583 min 2 sec)
Altitude of sun at 11:46:59 MST... 29.80 degrees

Upper air data from numerical model forecast valid on 11/27/2016 at 0500 MST

Freezing level.................. 10251 ft MSL (3081 ft AGL)
Convective condensation level... 13148 ft MSL (5978 ft AGL)
Lifted condensation level....... 10837 ft MSL (3668 ft AGL)
Lifted index.................... +4.3
K index......................... +23.1

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  -62.9 -81.2   245   68   35   1.5   0.8      M     M       M      M    M
 45000  -60.4 -76.7   240   85   44   2.2   1.2      M     M       M      M    M
 40000  -56.1 -69.0   240  130   67   2.9   1.6      M     M       M      M    M
 38000  -53.3 -63.9   240  140   72   6.4   3.5      M     M       M      M    M
 36000  -49.5 -57.1   235  141   73   6.4   3.5      M     M       M      M    M
 34000  -45.7 -50.3   235  142   73   5.4   3.0      M     M       M      M    M
 32000  -42.6 -44.7   235  135   70   5.2   2.9      M     M       M      M    M
 30000  -39.5 -39.1   235  128   66   3.9   2.1   32.4  90.2    20.1      M    M
 29000  -38.6 -37.5   230  115   59   3.0   1.6   29.5  85.1    18.1      M    M
 28000  -37.5 -35.5   230   98   50   3.0   1.6   26.2  79.2    15.8      M    M
 27000  -36.6 -33.9   225   85   44   2.6   1.4   23.8  74.9    14.1      M    M
 26000  -34.8 -30.6   225   73   38   6.7   3.7   22.3  72.1    13.0      M    M
 25000  -32.8 -27.0   225   61   32   6.7   3.7   21.1  70.0    12.2      M    M
 24000  -30.8 -23.4   220   50   26   6.6   3.6   20.1  68.1    11.5      M    M
 23000  -28.4 -19.1   220   45   23   9.2   5.0   19.5  67.2    11.1      M    M
 22000  -25.6 -14.1   220   44   22   9.2   5.0   19.3  66.7    11.1      M    M
 21000  -22.9  -9.2   220   42   22   9.1   5.0   19.2  66.5    11.1      M    M
 20000  -20.8  -5.4   220   41   21   6.7   3.7   18.2  64.8    10.3      M    M
 19500  -19.8  -3.6   215   41   21   6.7   3.7   17.7  63.8     9.9      M    M
 19000  -18.8  -1.8   215   41   21   6.7   3.7   17.2  62.9     9.5      M    M
 18500  -17.8  -0.0   215   40   21   6.7   3.7   16.7  62.0     9.1      M    M
 18000  -16.8   1.8   215   41   21   7.1   3.9   16.2  61.2     8.7      M    M
 17500  -15.8   3.6   220   43   22   7.1   3.9   15.8  60.4     8.3      M    M
 17000  -14.7   5.5   225   45   23   7.3   4.0   15.3  59.6     8.0      M    M
 16500  -13.6   7.5   225   45   23   7.5   4.1   14.9  58.9     7.6      M    M
 16000  -12.5   9.5   225   46   24   7.5   4.1   14.6  58.2     7.3      M    M
 15500  -11.4  11.5   225   46   23   7.6   4.2   14.2  57.6     7.0      M    M
 15000  -10.3  13.5   225   45   23   7.6   4.1   13.8  56.9     6.7      M    M
 14500   -9.2  15.4   225   45   23   7.8   4.3   13.5  56.3     6.4      M    M
 14000   -8.0  17.6   225   45   23   7.8   4.3   13.2  55.7     6.1      M    M
 13500   -6.9  19.6   225   44   23   7.7   4.2   12.9  55.1     5.8      M    M
 13000   -5.8  21.6   225   44   23   7.7   4.2   12.5  54.5     5.4      M    M
 12500   -4.7  23.5   225   44   23   7.4   4.0   12.2  53.9     5.1      M    M
 12000   -3.7  25.3   225   42   22   6.7   3.7   11.7  53.1     4.7      M    M
 11750   -3.2  26.2   225   40   21   6.6   3.6   11.5  52.7     4.5      M    M
 11500   -2.7  27.1   225   39   20   6.7   3.7   11.2  52.2     4.2      M    M
 11250   -2.2  28.0   225   37   19   6.6   3.6   11.0  51.8     4.0      M    M
 11000   -1.7  28.9   220   35   18   6.8   3.7   10.8  51.4     3.8      M    M
 10750   -1.2  29.8   220   32   17   7.0   3.9   10.5  51.0     3.6      M    M
 10500   -0.7  30.7   215   29   15   6.8   3.7   10.3  50.6     3.4      M    M
 10250    0.2  32.4   215   30   15   6.6   3.6    9.8  49.7     2.9      M    M
 10000    0.7  33.3   215   30   15   6.4   3.5    9.6  49.2     2.6      M    M
  9750    1.1  34.0   215   31   16   5.1   2.8    9.3  48.7     2.3      M    M
  9500    1.5  34.7   215   31   16   4.1   2.3    8.9  47.9     1.9      M    M
  9250    1.8  35.2   220   30   15   4.6   2.5    8.4  47.2     1.5      M    M
  9000    2.1  35.8   220   29   15   3.5   1.9    8.0  46.5     1.1      M    M
  8750    2.4  36.3   220   28   14   4.2   2.3    7.5  45.6     0.6      M    M
  8500    2.8  37.0   220   25   13   5.4   3.0    7.2  45.0     0.3      M    M
  8250    3.2  37.8   215   23   12   6.0   3.3    6.9  44.3    -0.0     93  0.5
  8000    3.6  38.5   215   21   11   2.4   1.3    6.5  43.8    -0.3     74  0.4
  7750    3.4  38.1   215   18    9  -9.6  -5.3    5.5  42.0    -1.2     72  0.4
  7500    2.4  36.3   210   12    6 -17.8  -9.8    3.7  38.7    -3.0     96  0.5
  7250    1.3  34.3   195    6    3  -6.5  -3.6    1.9  35.4    -4.8    120  0.6
  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 * * * * * *

           11/27/2016 at 0800 MST          |       11/27/2016 at 1100 MST
                                           |
K index... -2.5  LI... +0.1                | K index... -6.8  LI... +1.6
CAPE... +12.7  CIN... -71.2                | 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 -60.2 -76.4  250  47 24   2.6   1.4 | -57.5 -71.5  260  50 26   1.9   1.0
 45000 -56.3 -69.3  240  69 35   2.6   1.4 | -54.7 -66.5  240  66 34   1.9   1.0
 40000 -52.8 -63.0  240  91 47   2.2   1.2 | -51.7 -61.1  240  85 44   1.9   1.0
 38000 -51.0 -59.8  240  97 50   4.8   2.6 | -50.2 -58.4  240  89 46   3.9   2.1
 36000 -48.1 -54.6  235 101 52   4.8   2.6 | -47.8 -54.0  245  87 45   4.0   2.2
 34000 -45.2 -49.4  235 104 54   4.8   2.6 | -45.5 -49.9  245  85 44   4.0   2.2
 32000 -43.0 -45.4  235  98 50   3.5   1.9 | -43.2 -45.8  245  83 43   3.6   2.0
 30000 -40.9 -41.6  235  90 46   3.2   1.8 | -41.1 -42.0  250  82 42   3.6   2.0
 29000 -39.4 -38.9  235  86 44   5.6   3.1 | -39.9 -39.8  250  82 42   4.2   2.3
 28000 -37.8 -36.0  235  82 42   5.6   3.0 | -38.6 -37.5  255  83 43   4.2   2.3
 27000 -35.7 -32.3  235  78 40   5.5   3.0 | -37.4 -35.3  255  84 43   4.2   2.3
 26000 -34.2 -29.6  235  73 38   3.9   2.1 | -35.7 -32.3  260  83 43   5.3   2.9
 25000 -33.0 -27.4  230  67 34   3.9   2.1 | -34.1 -29.4  260  78 40   5.2   2.9
 24000 -31.9 -25.4  230  61 31   3.9   2.1 | -32.6 -26.7  260  74 38   5.2   2.9
 23000 -30.8 -23.4  230  55 28   3.2   1.8 | -31.1 -24.0  265  67 35   2.9   1.6
 22000 -29.8 -21.6  225  47 24   3.3   1.8 | -30.3 -22.5  260  52 27   2.8   1.5
 21000 -28.8 -19.8  225  40 21   3.4   1.9 | -29.5 -21.1  250  37 19   2.9   1.6
 20000 -27.0 -16.6  220  37 19   8.5   4.7 | -28.1 -18.6  235  28 15   7.3   4.0
 19500 -25.7 -14.3  215  37 19   8.7   4.8 | -27.0 -16.6  235  27 14   7.2   3.9
 19000 -24.4 -11.9  215  37 19   8.7   4.8 | -26.0 -14.8  235  26 14   7.2   3.9
 18500 -23.1  -9.6  210  37 19   8.7   4.8 | -24.9 -12.8  230  25 13   7.2   4.0
 18000 -21.8  -7.2  210  37 19   9.1   5.0 | -23.8 -10.8  230  24 13   7.4   4.1
 17500 -20.4  -4.7  210  38 19   9.5   5.2 | -22.6  -8.7  235  24 13   8.6   4.7
 17000 -19.0  -2.2  210  39 20   9.5   5.2 | -21.3  -6.3  240  25 13   8.6   4.7
 16500 -17.5   0.5  210  39 20   9.9   5.4 | -20.1  -4.2  245  26 13   7.6   4.2
 16000 -16.0   3.2  205  40 20   9.9   5.4 | -19.0  -2.2  250  27 14   7.5   4.1
 15500 -14.6   5.7  210  40 21   9.3   5.1 | -17.9  -0.2  255  28 14   7.6   4.1
 15000 -13.2   8.2  210  39 20   9.1   5.0 | -16.7   1.9  260  30 15   7.6   4.2
 14500 -11.9  10.6  215  39 20   8.3   4.5 | -15.6   3.9  265  32 16   7.6   4.2
 14000 -10.8  12.6  220  39 20   7.2   4.0 | -14.5   5.9  270  34 18   7.7   4.2
 13500  -9.7  14.5  225  39 20   6.9   3.8 | -13.3   8.1  275  37 19   7.7   4.2
 13000  -8.7  16.3  235  40 21   6.0   3.3 | -12.2  10.0  280  40 21   7.5   4.1
 12500  -7.8  18.0  245  41 21   5.3   2.9 | -11.1  12.0  280  43 22   7.5   4.1
 12000  -7.2  19.0  250  42 22   6.1   3.4 | -10.3  13.5  280  43 22   5.9   3.3
 11750  -6.6  20.1  250  43 22   7.6   4.2 |  -9.7  14.5  280  42 22   8.4   4.6
 11500  -6.1  21.0  255  43 22   7.3   4.0 |  -9.1  15.6  280  41 21   7.9   4.3
 11250  -5.6  21.9  255  44 22   6.4   3.5 |  -8.6  16.5  280  40 20   7.7   4.2
 11000  -5.1  22.8  255  43 22   7.5   4.1 |  -8.0  17.6  280  39 20   8.2   4.5
 10750  -4.5  23.9  255  43 22  10.1   5.5 |  -7.3  18.9  275  38 19   9.6   5.2
 10500  -3.7  25.3  255  43 22  10.1   5.5 |  -6.6  20.1  275  36 19   9.8   5.4
 10250  -3.1  26.4  255  42 22   8.5   4.7 |  -5.9  21.4  275  35 18   9.6   5.3
 10000  -1.9  28.6  250  42 22   8.6   4.7 |  -4.5  23.9  275  34 18   9.7   5.3
  9750  -1.3  29.7  250  41 21   8.3   4.5 |  -3.7  25.3  275  34 17   9.9   5.4
  9500  -0.8  30.6  250  40 21   5.8   3.2 |  -3.0  26.6  275  33 17  10.0   5.5
  9250  -0.4  31.3  245  38 20   5.0   2.8 |  -2.2  28.0  275  33 17  10.1   5.6
  9000  -0.1  31.8  245  36 19   5.5   3.0 |  -1.5  29.3  275  32 17  10.1   5.5
  8750   0.3  32.5  240  34 17   5.5   3.0 |  -0.7  30.7  275  32 16  10.2   5.6
  8500   0.7  33.3  240  31 16   5.8   3.2 |   0.1  32.2  275  31 16  10.5   5.8
  8250   1.1  34.0  235  28 15   4.7   2.6 |   0.8  33.4  275  30 15  10.5   5.8
  8000   1.5  34.7  235  26 13   8.6   4.7 |   1.6  34.9  275  29 15  10.6   5.8
  7750   2.2  36.0  230  24 12   6.4   3.5 |   2.5  36.5  275  28 14  14.2   7.8
  7500   2.1  35.8  225  18  9  -8.7  -4.8 |   3.8  38.8  275  24 12  19.5  10.7
  7250   2.0  35.6  215  12  6  21.6  11.8 |   5.1  41.2  270  20 10  10.2   5.6
  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

           11/27/2016 at 1400 MST          |       11/27/2016 at 1700 MST
                                           |
K index... -6.6  LI... +1.1                | K index... -7.1  LI... +1.3
CAPE... 0.0  CIN... -0.3                   | 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 -55.1 -67.2  250  43 22   0.3   0.2 | -53.5 -64.3  270  25 13   0.6   0.3
 45000 -54.7 -66.5  245  67 34   0.3   0.2 | -52.7 -62.9  245  52 27   0.6   0.3
 40000 -52.0 -61.6  240  82 42   1.9   1.0 | -51.5 -60.7  245  73 37   0.8   0.4
 38000 -50.6 -59.1  245  86 44   3.8   2.1 | -50.8 -59.4  245  78 40   3.4   1.9
 36000 -48.4 -55.1  245  84 43   3.8   2.1 | -48.9 -56.0  250  78 40   3.2   1.8
 34000 -46.1 -51.0  250  82 42   3.8   2.1 | -46.9 -52.4  255  79 41   3.2   1.8
 32000 -44.3 -47.7  250  83 43   2.6   1.4 | -45.1 -49.2  255  81 42   3.0   1.6
 30000 -42.8 -45.0  255  85 44   2.7   1.5 | -43.3 -45.9  255  83 43   3.0   1.6
 29000 -41.8 -43.2  255  86 44   3.9   2.2 | -42.4 -44.3  255  82 42   3.1   1.7
 28000 -40.6 -41.1  255  86 44   4.0   2.2 | -41.5 -42.7  255  77 39   3.1   1.7
 27000 -39.4 -38.9  260  87 45   4.0   2.2 | -40.5 -40.9  255  72 37   3.1   1.7
 26000 -38.2 -36.8  260  87 45   4.3   2.4 | -39.6 -39.3  260  67 34   3.3   1.8
 25000 -36.5 -33.7  260  78 40   4.7   2.6 | -38.2 -36.8  260  56 29   3.8   2.1
 24000 -35.1 -31.2  265  70 36   4.7   2.6 | -37.0 -34.6  265  48 25   3.8   2.1
 23000 -33.6 -28.5  265  63 32   5.4   3.0 | -35.8 -32.4  270  40 21   5.6   3.1
 22000 -32.0 -25.6  270  55 28   5.5   3.0 | -33.9 -29.0  275  36 18   6.4   3.5
 21000 -30.3 -22.5  270  47 24   5.5   3.0 | -32.0 -25.6  280  31 16   6.4   3.5
 20000 -28.5 -19.3  275  41 21   7.0   3.8 | -29.9 -21.8  285  29 15   8.4   4.6
 19500 -27.5 -17.5  275  39 20   6.9   3.8 | -28.7 -19.7  285  29 15   8.2   4.5
 19000 -26.4 -15.5  275  37 19   6.9   3.8 | -27.5 -17.5  285  29 15   8.2   4.5
 18500 -25.4 -13.7  275  35 18   6.9   3.8 | -26.2 -15.2  290  29 15   8.2   4.5
 18000 -24.4 -11.9  275  34 17   7.0   3.9 | -25.0 -13.0  290  29 15   8.2   4.5
 17500 -23.2  -9.8  275  34 18   8.1   4.4 | -23.7 -10.7  290  29 15   8.8   4.8
 17000 -22.0  -7.6  280  36 18   8.0   4.4 | -22.4  -8.3  290  28 15   8.8   4.8
 16500 -20.8  -5.4  280  36 19   8.3   4.6 | -21.1  -6.0  290  28 14   8.8   4.8
 16000 -19.6  -3.3  280  35 18   8.4   4.6 | -19.8  -3.6  285  27 14   8.8   4.8
 15500 -18.3  -0.9  275  33 17   8.7   4.7 | -18.5  -1.3  285  27 14   8.8   4.8
 15000 -17.0   1.4  275  31 16   8.9   4.9 | -17.2   1.0  285  27 14   8.7   4.8
 14500 -15.7   3.7  275  30 15   8.9   4.9 | -15.9   3.4  280  28 14   8.7   4.8
 14000 -14.4   6.1  275  30 15   8.5   4.7 | -14.6   5.7  285  30 15   8.3   4.6
 13500 -13.1   8.4  280  31 16   8.5   4.7 | -13.4   7.9  285  32 17   8.4   4.6
 13000 -11.9  10.6  280  33 17   7.7   4.2 | -12.2  10.0  285  36 18   7.6   4.2
 12500 -10.8  12.6  280  36 19   8.0   4.4 | -11.1  12.0  290  40 21   8.2   4.5
 12000  -9.9  14.2  280  36 19   5.9   3.2 | -10.2  13.6  290  43 22   6.2   3.4
 11750  -9.3  15.3  280  36 18   8.4   4.6 |  -9.6  14.7  290  44 23   8.7   4.8
 11500  -8.8  16.2  280  35 18   7.8   4.3 |  -9.0  15.8  290  45 23   8.5   4.7
 11250  -8.2  17.2  280  35 18   7.8   4.3 |  -8.3  17.1  290  46 23   6.6   3.6
 11000  -7.6  18.3  280  34 17   8.4   4.6 |  -8.0  17.6  290  44 23   5.2   2.9
 10750  -7.0  19.4  275  33 17   9.4   5.2 |  -7.5  18.5  285  42 22   7.3   4.0
 10500  -6.3  20.7  275  32 16   9.5   5.2 |  -7.0  19.4  285  41 21   7.3   4.0
 10250  -5.6  21.9  275  31 16   9.7   5.3 |  -6.4  20.5  285  39 20   8.0   4.4
 10000  -4.8  23.4  275  31 16   9.7   5.3 |  -5.8  21.6  285  38 19   8.7   4.8
  9750  -3.3  26.1  275  30 16  10.1   5.6 |  -4.5  23.9  280  35 18   8.5   4.7
  9500  -2.6  27.3  275  30 15  10.0   5.5 |  -3.9  25.0  280  34 17   9.3   5.1
  9250  -1.9  28.6  275  29 15   9.9   5.4 |  -3.2  26.2  280  33 17  10.1   5.5
  9000  -1.1  30.0  275  29 15   9.9   5.4 |  -2.4  27.7  280  32 17   9.5   5.2
  8750  -0.4  31.3  275  29 15  10.1   5.6 |  -1.8  28.8  280  31 16   8.6   4.7
  8500   0.4  32.7  275  28 14  10.5   5.8 |  -1.1  30.0  280  30 15   8.6   4.7
  8250   1.2  34.2  275  27 14  10.7   5.9 |  -0.5  31.1  275  28 14   8.8   4.8
  8000   2.0  35.6  275  26 14  10.3   5.7 |   0.2  32.4  275  26 14   9.3   5.1
  7750   2.8  37.0  275  26 13  13.4   7.3 |   0.8  33.4  275  25 13   6.9   3.8
  7500   4.1  39.4  275  22 11  19.5  10.7 |   1.1  34.0  275  19 10   1.0   0.6
  7250   5.3  41.5  270  19 10   8.7   4.8 |   1.4  34.5  275  13  7  10.0   5.5
  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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