Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 091231
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
1231 UTC Monday, January 9, 2017

This forecast is for Monday, January 9, 2017:

If the trigger temperature of 59.0 F/15.0 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 163 ft/min (0.8 m/s)
   Maximum height of thermals.................. 9848 ft MSL (3090 ft AGL)

Forecast maximum temperature................... 56.0 F/13.8 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ More than 30 mph
Height of the -3 thermal index................. 8250 ft MSL (1492 ft AGL)
Thermal soaring outlook for Tuesday 01/10...... Fair

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

Remarks...

Sunrise/Sunset.................... 07:17:31 / 16:55:18 MST
Total possible sunshine........... 9 hr 37 min 47 sec (577 min 47 sec)
Altitude of sun at 12:06:17 MST... 29.13 degrees

Upper air data from numerical model forecast valid on 01/09/2017 at 0500 MST

Freezing level.................. 14565 ft MSL (7807 ft AGL)
Convective condensation level... 18911 ft MSL (12153 ft AGL)
Lifted condensation level....... 14072 ft MSL (7314 ft AGL)
Lifted index.................... +5.8
K index......................... -4.6

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -71.0 -95.8   275   77   40  -1.0  -0.5      M     M       M      M    M
 45000  -72.5 -98.5   285   71   36   1.3   0.7      M     M       M      M    M
 40000  -65.9 -86.6   285   61   31   4.3   2.4      M     M       M      M    M
 38000  -61.3 -78.3   280   62   32   8.9   4.9      M     M       M      M    M
 36000  -56.0 -68.8   280   65   34   8.9   4.9      M     M       M      M    M
 34000  -50.6 -59.1   280   68   35   9.1   5.0      M     M       M      M    M
 32000  -45.1 -49.2   275   71   37   9.1   5.0      M     M       M      M    M
 30000  -39.7 -39.5   280   71   37   9.1   5.0   29.8  85.7    12.7      M    M
 29000  -37.0 -34.6   280   69   36   9.1   5.0   29.5  85.2    12.6      M    M
 28000  -34.2 -29.6   280   67   35   9.2   5.0   29.4  84.9    12.7      M    M
 27000  -30.9 -23.6   280   65   33   8.8   4.8   29.1  84.3    12.6      M    M
 26000  -28.2 -18.8   280   64   33   8.8   4.8   28.7  83.6    12.4      M    M
 25000  -25.6 -14.1   285   63   32   8.8   4.8   28.4  83.1    12.3      M    M
 24000  -23.0  -9.4   285   62   32   8.6   4.7   28.1  82.5    12.2      M    M
 23000  -20.4  -4.7   285   61   31   8.6   4.7   27.6  81.6    11.9      M    M
 22000  -17.8  -0.0   285   60   31   8.6   4.7   27.2  81.0    11.7      M    M
 21000  -15.4   4.3   280   59   30   7.6   4.2   26.7  80.1    11.4      M    M
 20000  -13.1   8.4   280   57   29   7.7   4.2   25.9  78.7    10.9      M    M
 19500  -12.0  10.4   280   56   29   7.7   4.2   25.6  78.1    10.6      M    M
 19000  -10.8  12.6   280   56   29   7.7   4.2   25.3  77.5    10.4      M    M
 18500   -9.7  14.5   280   54   28   7.2   4.0   24.9  76.9    10.1      M    M
 18000   -8.6  16.5   280   50   26   7.3   4.0   24.5  76.1     9.8      M    M
 17500   -7.6  18.3   275   46   24   7.8   4.3   24.1  75.4     9.5      M    M
 17000   -6.3  20.7   270   41   21   8.5   4.7   23.9  75.0     9.3      M    M
 16500   -5.0  23.0   265   37   19   8.6   4.7   23.7  74.6     9.2      M    M
 16000   -3.8  25.2   260   35   18   8.3   4.6   23.5  74.2     9.0      M    M
 15500   -2.5  27.5   255   34   18   8.3   4.6   23.2  73.8     8.9      M    M
 15000   -1.3  29.7   255   35   18   8.1   4.5   23.0  73.4     8.7      M    M
 14500   -0.1  31.8   255   36   18   8.0   4.4   22.7  72.9     8.5      M    M
 14000    1.1  34.0   255   37   19   7.1   3.9   22.4  72.4     8.2      M    M
 13500    2.2  36.0   265   46   24   5.0   2.8   21.3  70.4     7.3      M    M
 13000    2.9  37.2   270   52   27   3.2   1.7   20.5  68.9     6.5      M    M
 12500    3.3  37.9   270   59   30   2.1   1.1   19.4  66.9     5.5      M    M
 12000    3.4  38.1   275   70   36   1.2   0.6   17.9  64.3     4.1      M    M
 11750    3.5  38.3   280   72   37   2.6   1.4   17.3  63.2     3.6      M    M
 11500    3.7  38.7   280   74   38   2.3   1.2   16.8  62.2     3.0      M    M
 11250    3.8  38.8   280   77   39   2.1   1.2   16.2  61.1     2.4      M    M
 11000    4.0  39.2   280   81   42   3.7   2.0   15.6  60.1     1.9      M    M
 10750    4.3  39.7   280   80   41   5.2   2.8   15.2  59.4     1.5      M    M
 10500    4.7  40.5   280   79   41   4.7   2.6   14.8  58.7     1.1      M    M
 10250    5.0  41.0   280   78   40   5.4   2.9   14.5  58.1     0.7      M    M
 10000    5.3  41.5   280   76   39   3.0   1.6   14.1  57.4     0.3      M    M
  9750    5.4  41.7   280   72   37   2.0   1.1   13.5  56.2    -0.4    257  1.3
  9500    5.6  42.1   280   68   35   3.6   1.9   13.0  55.3    -0.9    243  1.2
  9250    5.8  42.4   280   65   33   3.1   1.7   12.5  54.4    -1.5    230  1.2
  9000    6.0  42.8   275   61   32   5.2   2.8   12.0  53.6    -1.9    216  1.1
  8750    6.4  43.5   275   58   30   5.7   3.1   11.7  53.1    -2.3    196  1.0
  8500    6.8  44.2   275   53   27   4.8   2.6   11.4  52.5    -2.6    178  0.9
  8250    7.1  44.8   275   49   25   4.7   2.6   11.0  51.8    -3.0    160  0.8
  8000    7.4  45.3   275   45   23   3.3   1.8   10.6  51.0    -3.5    144  0.7
  7750    7.6  45.7   275   40   21   3.0   1.7   10.1  50.1    -4.0    131  0.7
  7500    7.9  46.2   275   35   18   6.9   3.8    9.7  49.4    -4.4    114  0.6
  7250    8.3  46.9   275   29   15  -2.6  -1.4    9.3  48.7    -4.8     97  0.5
  7000    7.1  44.8   275   24   12 -26.4 -14.5    8.0  46.4    -6.2    123  0.6
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/09/2017 at 0800 MST          |       01/09/2017 at 1100 MST
                                           |
K index... 0.0  LI... +2.6                 | K index... -6.6  LI... +4.6
CAPE... 0.0  CIN... -0.1                   | 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 -71.2 -96.2  270  81 41   2.1   1.2 | -71.5 -96.7  260  84 43   1.3   0.7
 45000 -68.1 -90.6  280  65 33   1.9   1.0 | -69.5 -93.1  270  76 39   1.2   0.6
 40000 -65.7 -86.3  275  86 44   1.6   0.9 | -68.0 -90.4  270  77 40   1.0   0.5
 38000 -62.4 -80.3  270  84 43   7.9   4.4 | -63.9 -83.0  265  68 35   9.9   5.4
 36000 -57.0 -70.6  265  73 37   7.9   4.4 | -58.0 -72.4  260  54 28   9.9   5.4
 34000 -51.9 -61.4  265  64 33   9.5   5.2 | -52.1 -61.8  250  44 23   9.7   5.3
 32000 -46.2 -51.2  260  57 29   9.5   5.2 | -46.3 -51.3  250  43 22   9.7   5.3
 30000 -40.5 -40.9  260  51 27   9.7   5.3 | -40.5 -40.9  240  41 21   9.6   5.3
 29000 -37.6 -35.7  260  50 26   9.7   5.3 | -37.6 -35.7  240  40 21   9.6   5.3
 28000 -34.7 -30.5  260  49 25   9.7   5.3 | -34.0 -29.2  235  39 20   9.6   5.3
 27000 -31.8 -25.2  260  49 25   9.1   5.0 | -31.1 -24.0  230  37 19   9.3   5.1
 26000 -29.1 -20.4  260  52 27   9.1   5.0 | -28.3 -18.9  230  35 18   9.3   5.1
 25000 -26.4 -15.5  265  55 28   9.1   5.0 | -25.5 -13.9  225  34 17   9.3   5.1
 24000 -23.7 -10.7  265  57 29   8.7   4.8 | -22.7  -8.9  225  33 17   9.4   5.1
 23000 -20.5  -4.9  265  60 31   8.5   4.7 | -19.9  -3.8  230  33 17   9.4   5.1
 22000 -18.0  -0.4  265  62 32   8.5   4.7 | -17.1   1.2  235  33 17   9.4   5.1
 21000 -15.5   4.1  265  64 33   8.2   4.5 | -14.3   6.3  240  34 18   8.5   4.7
 20000 -13.0   8.6  265  66 34   8.3   4.5 | -11.8  10.8  245  38 19   8.6   4.7
 19500 -11.8  10.8  265  67 34   8.3   4.5 | -10.5  13.1  245  40 20   8.6   4.7
 19000 -10.6  12.9  265  68 35   8.3   4.5 |  -9.2  15.4  250  42 21   8.7   4.8
 18500  -9.3  15.3  260  63 32   8.4   4.6 |  -7.9  17.8  250  44 23   8.0   4.4
 18000  -8.1  17.4  255  52 27   8.3   4.6 |  -6.8  19.8  255  47 24   7.8   4.3
 17500  -6.9  19.6  250  42 22   8.2   4.5 |  -5.6  21.9  255  50 26   7.7   4.2
 17000  -5.7  21.7  250  44 23   8.0   4.4 |  -4.5  23.9  260  53 27   7.2   3.9
 16500  -4.5  23.9  255  47 24   8.0   4.4 |  -3.4  25.9  260  56 29   7.3   4.0
 16000  -3.3  26.1  255  49 25   7.8   4.3 |  -2.4  27.7  265  59 31   6.3   3.5
 15500  -2.2  28.0  255  51 26   7.8   4.3 |  -1.5  29.3  265  63 32   6.1   3.3
 15000  -1.0  30.2  260  54 28   7.4   4.1 |  -0.6  30.9  265  66 34   5.6   3.1
 14500   0.1  32.2  260  56 29   7.2   4.0 |   0.1  32.2  270  68 35   4.7   2.6
 14000   1.1  34.0  265  58 30   6.9   3.8 |   0.8  33.4  270  71 37   4.7   2.6
 13500   2.1  35.8  265  62 32   6.2   3.4 |   1.4  34.5  270  74 38   3.7   2.0
 13000   3.0  37.4  270  65 34   6.2   3.4 |   1.9  35.4  270  78 40   3.7   2.1
 12500   3.9  39.0  270  68 35   6.8   3.7 |   2.5  36.5  270  80 41   4.9   2.7
 12000   4.7  40.5  275  72 37   3.7   2.0 |   3.0  37.4  270  83 42   2.3   1.2
 11750   5.0  41.0  275  74 38   4.6   2.5 |   3.2  37.8  270  84 43   2.8   1.5
 11500   5.4  41.7  275  76 39   4.9   2.7 |   3.4  38.1  270  85 44   3.2   1.8
 11250   5.7  42.3  275  77 40   5.0   2.8 |   3.6  38.5  270  85 44   3.6   2.0
 11000   6.1  43.0  275  79 40   4.1   2.3 |   3.9  39.0  270  85 44   2.7   1.5
 10750   6.3  43.3  275  80 41   2.8   1.5 |   4.0  39.2  270  87 45   1.9   1.0
 10500   6.5  43.7  275  80 41   2.7   1.5 |   4.1  39.4  270  86 44   2.3   1.3
 10250   6.7  44.1  275  81 42   2.5   1.3 |   4.4  39.9  270  81 42   2.2   1.2
 10000   6.9  44.4  275  82 42   3.7   2.0 |   4.5  40.1  270  78 40   0.8   0.4
  9750   7.1  44.8  275  82 42   3.0   1.6 |   4.5  40.1  265  75 39   1.7   1.0
  9500   7.3  45.1  275  80 41   1.8   1.0 |   4.7  40.5  265  70 36   3.5   1.9
  9250   7.4  45.3  275  79 41   1.3   0.7 |   4.9  40.8  265  66 34   2.3   1.3
  9000   7.4  45.3  275  77 40  -1.0  -0.6 |   5.1  41.2  265  62 32   5.5   3.0
  8750   7.3  45.1  275  72 37  -0.2  -0.1 |   5.7  42.3  265  58 30   7.7   4.3
  8500   7.3  45.1  275  67 35   1.9   1.0 |   6.2  43.2  265  54 28   6.3   3.5
  8250   7.4  45.3  270  63 32   1.2   0.6 |   6.7  44.1  265  49 25   6.8   3.7
  8000   7.4  45.3  270  58 30   1.0   0.5 |   7.1  44.8  265  45 23   6.1   3.3
  7750   7.3  45.1  270  51 26  -4.1  -2.2 |   7.5  45.5  260  40 20   2.6   1.4
  7500   6.6  43.9  270  39 20 -12.1  -6.6 |   7.4  45.3  260  30 16  -1.9  -1.0
  7250   5.9  42.6  270  28 14   2.1   1.2 |   7.4  45.3  255  21 11   5.7   3.1
  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

           01/09/2017 at 1400 MST          |       01/09/2017 at 1700 MST
                                           |
K index... -3.6  LI... +3.2                | K index... -1.6  LI... +3.2
CAPE... 0.0  CIN... M                      | 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 -70.7 -95.3  260  87 45   1.5   0.8 | -69.4 -92.9  265  75 38   1.5   0.8
 45000 -68.5 -91.3  265  77 39   1.6   0.9 | -67.1 -88.8  265  70 36   1.6   0.9
 40000 -67.9 -90.2  260  90 46   0.4   0.2 | -66.7 -88.1  250  95 49   0.2   0.1
 38000 -64.1 -83.4  260  89 46   9.9   5.4 | -64.0 -83.2  245 101 52   9.4   5.1
 36000 -58.1 -72.6  255  83 43   9.9   5.4 | -58.3 -72.9  245 100 52   9.4   5.1
 34000 -52.2 -62.0  255  75 39   9.6   5.3 | -52.8 -63.0  245  97 50   8.5   4.6
 32000 -46.5 -51.7  245  64 33   9.6   5.3 | -47.7 -53.9  240  84 43   8.5   4.7
 30000 -40.8 -41.4  235  57 29   9.4   5.2 | -42.4 -44.3  235  72 37   9.2   5.1
 29000 -37.9 -36.2  235  56 29   9.4   5.1 | -39.0 -38.2  230  67 35   9.2   5.1
 28000 -35.1 -31.2  235  56 29   9.4   5.1 | -36.2 -33.2  230  64 33   9.3   5.1
 27000 -32.3 -26.1  235  56 29   9.2   5.0 | -33.4 -28.1  225  61 31   9.0   4.9
 26000 -29.6 -21.3  235  53 27   9.1   5.0 | -30.8 -23.4  225  58 30   8.9   4.9
 25000 -26.9 -16.4  240  51 26   9.1   5.0 | -28.1 -18.6  225  56 29   8.9   4.9
 24000 -23.6 -10.5  245  48 25   8.3   4.5 | -25.4 -13.7  225  53 27   8.6   4.7
 23000 -21.2  -6.2  245  43 22   8.1   4.4 | -23.1  -9.6  230  50 26   7.8   4.3
 22000 -18.7  -1.7  245  38 20   8.1   4.4 | -20.7  -5.3  235  47 24   7.8   4.3
 21000 -16.3   2.7  245  34 18   8.6   4.7 | -18.4  -1.1  235  45 23   7.5   4.1
 20000 -13.7   7.3  250  34 18   8.6   4.7 | -16.2   2.8  240  42 22   7.2   4.0
 19500 -12.4   9.7  250  34 18   8.6   4.7 | -15.1   4.8  245  41 21   7.2   4.0
 19000 -11.2  11.8  250  34 18   8.6   4.7 | -14.1   6.6  245  40 21   7.2   4.0
 18500  -9.9  14.2  255  35 18   7.8   4.3 | -13.0   8.6  250  39 20   7.2   4.0
 18000  -8.8  16.2  255  36 19   7.3   4.0 | -11.9  10.6  255  39 20   7.3   4.0
 17500  -7.7  18.1  260  38 20   7.2   4.0 | -10.8  12.6  260  40 21   7.3   4.0
 17000  -6.7  19.9  265  40 21   7.1   3.9 |  -9.7  14.5  260  41 21   6.9   3.8
 16500  -5.6  21.9  265  42 22   7.1   3.9 |  -8.7  16.3  265  42 22   6.8   3.7
 16000  -4.6  23.7  270  44 23   7.0   3.8 |  -7.7  18.1  270  44 22   7.1   3.9
 15500  -3.5  25.7  270  45 23   6.9   3.8 |  -6.6  20.1  270  44 23   7.5   4.1
 15000  -2.5  27.5  275  47 24   7.1   3.9 |  -5.5  22.1  275  45 23   7.5   4.1
 14500  -1.4  29.5  275  47 24   7.7   4.2 |  -4.4  24.1  275  46 24   7.4   4.0
 14000  -0.2  31.6  275  47 24   7.8   4.3 |  -3.3  26.1  275  47 24   7.4   4.1
 13500   0.8  33.4  275  48 25   7.0   3.9 |  -2.2  28.0  280  48 25   7.4   4.0
 13000   1.9  35.4  275  50 26   7.2   4.0 |  -1.1  30.0  280  47 24   7.3   4.0
 12500   2.9  37.2  275  53 27   6.6   3.6 |   0.1  32.2  280  48 24   9.3   5.1
 12000   3.5  38.3  275  58 30   2.9   1.6 |   1.2  34.2  280  49 25   5.1   2.8
 11750   3.7  38.7  270  61 31   2.8   1.6 |   1.5  34.7  280  49 25   5.2   2.8
 11500   3.9  39.0  270  64 33   0.9   0.5 |   1.9  35.4  280  50 26   4.9   2.7
 11250   3.9  39.0  270  66 34   0.7   0.4 |   2.2  36.0  280  52 27   5.0   2.8
 11000   3.9  39.0  270  69 35  -0.8  -0.4 |   2.6  36.7  280  55 28   4.0   2.2
 10750   3.7  38.7  270  73 38  -2.1  -1.2 |   2.8  37.0  280  58 30   2.7   1.5
 10500   3.6  38.5  270  75 39   0.0   0.0 |   3.0  37.4  280  60 31   1.3   0.7
 10250   3.6  38.5  270  73 38   1.0   0.6 |   3.1  37.6  280  60 31   1.6   0.9
 10000   3.6  38.5  270  71 37   0.5   0.3 |   3.2  37.8  280  61 31   0.5   0.3
  9750   3.6  38.5  270  67 34   2.8   1.5 |   3.2  37.8  275  61 31   1.8   1.0
  9500   3.9  39.0  270  63 33   6.1   3.4 |   3.4  38.1  275  57 30   3.7   2.0
  9250   4.3  39.7  270  60 31   4.8   2.6 |   3.6  38.5  275  54 28   3.2   1.7
  9000   4.7  40.5  270  56 29   6.9   3.8 |   3.8  38.8  275  51 26   3.5   1.9
  8750   5.3  41.5  270  53 28   8.4   4.6 |   4.1  39.4  275  46 24   5.9   3.2
  8500   5.9  42.6  270  50 26   7.7   4.2 |   4.7  40.5  275  43 22   7.6   4.1
  8250   6.4  43.5  270  47 24   7.9   4.4 |   5.2  41.4  275  40 21   7.3   4.0
  8000   7.0  44.6  270  43 22   7.7   4.2 |   5.7  42.3  275  37 19   6.7   3.7
  7750   7.5  45.5  265  39 20   6.2   3.4 |   6.1  43.0  275  33 17   0.8   0.4
  7500   7.9  46.2  265  31 16   4.0   2.2 |   5.8  42.4  275  24 12  -6.5  -3.6
  7250   8.2  46.8  265  23 12   7.8   4.3 |   5.5  41.9  280  16  8   5.7   3.1
  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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