Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 141221
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0521 MST Saturday, January 14, 2017

This forecast is for Saturday, January 14, 2017:

If the trigger temperature of 48.8 F/9.3 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8617 ft MSL (1859 ft AGL)

Forecast maximum temperature................... 42.0 F/6.0 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............ 20 mph or less
Height of the -3 thermal index................. 7644 ft MSL (887 ft AGL)
Thermal soaring outlook for Sunday 01/15....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:16:14 / 17:00:25 MST
Total possible sunshine........... 9 hr 44 min 10 sec (584 min 10 sec)
Altitude of sun at 12:08:11 MST... 29.95 degrees

Upper air data from numerical model forecast valid on 01/14/2017 at 0500 MST

Freezing level.................. 7312 ft MSL (554 ft AGL)
Additional freezing level....... 9874 ft MSL (3116 ft AGL)
Convective condensation level... 14584 ft MSL (7826 ft AGL)
Lifted condensation level....... 11432 ft MSL (4675 ft AGL)
Lifted index.................... +5.7
K index......................... +19.7

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  -62.4 -80.3   255   37   19   1.9   1.0      M     M       M      M    M
 45000  -59.6 -75.3   245   41   21   1.2   0.7      M     M       M      M    M
 40000  -60.0 -76.0   245   68   35  -0.3  -0.2      M     M       M      M    M
 38000  -58.9 -74.0   240   77   40   4.1   2.2      M     M       M      M    M
 36000  -56.5 -69.7   235   85   44   4.1   2.2      M     M       M      M    M
 34000  -53.4 -64.1   230   91   47   5.9   3.2      M     M       M      M    M
 32000  -49.9 -57.8   230   82   42   5.9   3.3      M     M       M      M    M
 30000  -45.9 -50.6   230   74   38   8.0   4.4   23.6  74.5    13.8      M    M
 29000  -43.5 -46.3   230   69   36   8.0   4.4   22.9  73.1    13.4      M    M
 28000  -41.1 -42.0   235   65   34   8.0   4.4   22.2  72.0    13.1      M    M
 27000  -38.7 -37.7   235   62   32   8.3   4.5   21.7  71.0    12.8      M    M
 26000  -36.2 -33.2   235   61   31   8.3   4.6   21.0  69.9    12.4      M    M
 25000  -33.7 -28.7   240   60   31   8.3   4.6   20.5  68.9    12.1      M    M
 24000  -31.2 -24.2   240   59   30   8.3   4.5   20.1  68.2    11.9      M    M
 23000  -28.8 -19.8   240   58   30   8.3   4.5   19.4  67.0    11.5      M    M
 22000  -26.3 -15.3   240   56   29   8.3   4.5   18.9  66.1    11.2      M    M
 21000  -23.9 -11.0   240   54   28   7.3   4.0   18.4  65.1    10.8      M    M
 20000  -21.7  -7.1   240   50   26   7.4   4.1   17.5  63.5    10.2      M    M
 19500  -20.6  -5.1   240   48   25   7.4   4.1   17.1  62.8     9.9      M    M
 19000  -19.5  -3.1   240   47   24   7.4   4.1   16.8  62.2     9.6      M    M
 18500  -18.4  -1.1   240   45   23   7.3   4.0   16.4  61.5     9.3      M    M
 18000  -17.4   0.7   240   43   22   7.3   4.0   16.0  60.7     9.0      M    M
 17500  -16.3   2.7   240   41   21   7.2   4.0   15.6  60.0     8.6      M    M
 17000  -15.2   4.6   240   40   21   7.0   3.8   15.1  59.2     8.3      M    M
 16500  -14.2   6.4   240   39   20   7.0   3.8   14.6  58.3     7.9      M    M
 16000  -12.6   9.3   240   37   19   7.4   4.1   14.0  57.2     7.4      M    M
 15500  -11.4  11.5   240   36   18   7.4   4.1   13.6  56.6     7.1      M    M
 15000  -10.4  13.3   240   35   18   7.3   4.0   13.2  55.8     6.7      M    M
 14500   -9.3  15.3   240   34   18   7.3   4.0   12.8  55.1     6.4      M    M
 14000   -8.1  17.4   240   33   17   8.0   4.4   12.5  54.5     6.1      M    M
 13500   -7.0  19.4   240   33   17   8.1   4.4   12.2  54.0     5.8      M    M
 13000   -5.8  21.6   240   32   16   7.2   4.0   11.9  53.4     5.5      M    M
 12500   -4.8  23.4   235   31   16   7.4   4.0   11.5  52.7     5.2      M    M
 12000   -3.7  25.3   235   29   15   6.8   3.7   11.1  51.9     4.8      M    M
 11750   -3.2  26.2   235   28   14   6.7   3.7   10.8  51.5     4.6      M    M
 11500   -2.7  27.1   235   27   14   6.7   3.7   10.6  51.1     4.3      M    M
 11250   -2.3  27.9   235   26   13   7.2   3.9   10.4  50.7     4.1      M    M
 11000   -1.7  28.9   240   24   13   6.5   3.6   10.2  50.3     3.9      M    M
 10750   -1.3  29.7   240   23   12   5.5   3.0    9.9  49.7     3.6      M    M
 10500   -0.9  30.4   240   22   11   5.8   3.2    9.5  49.2     3.3      M    M
 10250   -0.5  31.1   240   21   11   5.5   3.0    9.2  48.6     2.9      M    M
 10000   -0.1  31.8   240   19   10   5.0   2.8    8.9  48.0     2.6      M    M
  9750    0.2  32.4   245   18    9   4.5   2.5    8.5  47.3     2.2      M    M
  9500    0.5  32.9   245   16    8   4.0   2.2    8.1  46.5     1.8      M    M
  9250    0.8  33.4   245   14    7   2.6   1.4    7.6  45.6     1.4      M    M
  9000    1.0  33.8   245   12    6   1.3   0.7    7.0  44.5     0.8      M    M
  8750    1.1  34.0   250   10    5   2.8   1.6    6.4  43.5     0.2      M    M
  8500    1.4  34.5   250    7    4   1.9   1.1    5.9  42.5    -0.3    171  0.9
  8250    1.4  34.5   250    6    3  -1.1  -0.6    5.1  41.2    -1.0    162  0.8
  8000    1.3  34.3   255    4    2  -1.1  -0.6    4.3  39.7    -1.8    157  0.8
  7750    1.3  34.3   265    3    1  -2.0  -1.1    3.5  38.2    -2.6    152  0.8
  7500    0.9  33.6   275    2    1 -10.7  -5.9    2.4  36.3    -3.6    156  0.8
  7250   -0.3  31.5   285    3    1 -17.2  -9.4    0.9  33.6    -5.1    183  0.9
  7000   -1.4  29.5   290    3    2 -12.4  -6.8   -0.6  30.9    -6.6    211  1.1
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/14/2017 at 0800 MST          |       01/14/2017 at 1100 MST
                                           |
K index... +23.7  LI... +0.3               | K index... +22.6  LI... +1.5
CAPE... 0.0  CIN... -0.5                   | 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 -62.2 -80.0  255  37 19   1.9   1.1 | -62.6 -80.7  255  34 17   1.5   0.8
 45000 -59.3 -74.7  250  42 22   1.1   0.6 | -60.4 -76.7  245  41 21   1.2   0.7
 40000 -60.8 -77.4  240  71 36  -1.0  -0.6 | -60.2 -76.4  240  66 34   0.1   0.0
 38000 -59.4 -74.9  240  78 40   5.7   3.1 | -58.6 -73.5  235  71 37   4.5   2.5
 36000 -56.0 -68.8  240  81 42   5.7   3.1 | -55.9 -68.6  235  73 38   4.5   2.5
 34000 -52.2 -62.0  240  82 42   5.1   2.8 | -52.9 -63.2  235  74 38   6.8   3.8
 32000 -49.2 -56.6  235  75 39   5.1   2.8 | -48.8 -55.8  235  72 37   6.9   3.8
 30000 -45.8 -50.4  230  68 35   6.7   3.7 | -44.8 -48.6  235  68 35   5.9   3.2
 29000 -43.8 -46.8  230  63 33   6.8   3.7 | -43.1 -45.6  230  64 33   5.9   3.2
 28000 -41.7 -43.1  230  58 30   6.8   3.7 | -41.3 -42.3  230  60 31   5.9   3.2
 27000 -39.6 -39.3  230  54 28   8.9   4.9 | -38.9 -38.0  225  55 28   9.2   5.1
 26000 -36.8 -34.2  230  50 26   9.3   5.1 | -36.3 -33.3  225  52 27   8.8   4.9
 25000 -34.0 -29.2  230  47 24   9.3   5.1 | -33.6 -28.5  225  48 25   8.9   4.9
 24000 -31.3 -24.3  230  44 23   8.5   4.7 | -31.0 -23.8  225  45 23   8.4   4.6
 23000 -28.8 -19.8  230  43 22   8.2   4.5 | -28.5 -19.3  225  44 22   8.3   4.6
 22000 -26.4 -15.5  230  42 22   8.2   4.5 | -26.1 -15.0  230  43 22   8.3   4.6
 21000 -24.0 -11.2  230  41 21   7.5   4.1 | -23.6 -10.5  235  43 22   8.1   4.4
 20000 -21.8  -7.2  230  38 20   7.6   4.2 | -21.2  -6.2  235  43 22   8.1   4.5
 19500 -20.7  -5.3  230  37 19   7.6   4.2 | -20.0  -4.0  235  43 22   8.2   4.5
 19000 -19.5  -3.1  230  36 18   7.6   4.2 | -18.8  -1.8  235  43 22   8.3   4.6
 18500 -18.4  -1.1  230  35 18   8.0   4.4 | -17.7   0.1  235  43 22   7.0   3.9
 18000 -17.2   1.0  230  34 17   8.1   4.4 | -16.7   1.9  235  42 22   7.2   3.9
 17500 -16.0   3.2  230  33 17   7.8   4.3 | -15.6   3.9  235  41 21   7.3   4.0
 17000 -14.9   5.2  230  33 17   7.3   4.0 | -14.5   5.9  235  40 21   7.4   4.1
 16500 -13.3   8.1  230  34 17   6.9   3.8 | -13.4   7.9  235  40 20   7.5   4.1
 16000 -12.4   9.7  230  34 17   6.7   3.7 | -12.4   9.7  235  39 20   7.4   4.1
 15500 -11.4  11.5  230  33 17   6.7   3.7 | -11.3  11.7  230  38 20   7.6   4.2
 15000 -10.4  13.3  230  33 17   6.6   3.6 | -10.3  13.5  230  37 19   5.3   2.9
 14500  -9.4  15.1  230  32 16   6.6   3.6 |  -9.6  14.7  230  35 18   5.3   2.9
 14000  -8.5  16.7  230  30 16   6.2   3.4 |  -8.4  16.9  230  32 16   5.1   2.8
 13500  -7.6  18.3  235  29 15   6.3   3.5 |  -7.7  18.1  230  29 15   5.1   2.8
 13000  -6.7  19.9  235  26 14   6.0   3.3 |  -6.8  19.8  230  27 14   6.3   3.5
 12500  -5.8  21.6  240  24 12   5.9   3.2 |  -5.9  21.4  225  24 13   6.2   3.4
 12000  -4.8  23.4  240  22 11   6.9   3.8 |  -5.0  23.0  225  22 11   6.9   3.8
 11750  -4.3  24.3  245  21 11   6.5   3.6 |  -4.5  23.9  225  21 11   7.1   3.9
 11500  -3.9  25.0  245  20 10   6.6   3.6 |  -4.0  24.8  225  20 10   6.8   3.7
 11250  -3.4  25.9  245  19 10   6.6   3.6 |  -3.5  25.7  225  19 10   8.0   4.4
 11000  -2.9  26.8  245  18  9   7.1   3.9 |  -2.9  26.8  225  18  9   7.1   3.9
 10750  -2.3  27.9  245  17  9   7.7   4.2 |  -2.5  27.5  225  17  9   5.3   2.9
 10500  -1.8  28.8  240  16  8   7.6   4.1 |  -2.0  28.4  225  16  8   5.8   3.2
 10250  -1.2  29.8  240  16  8   7.4   4.1 |  -1.6  29.1  225  14  7   6.7   3.7
 10000  -0.7  30.7  240  14  7   7.0   3.8 |  -1.1  30.0  225  13  7   7.0   3.9
  9750  -0.2  31.6  235  13  7   6.1   3.4 |  -0.6  30.9  225  12  6   5.6   3.1
  9500   0.2  32.4  230  12  6   5.1   2.8 |  -0.3  31.5  225  11  6   4.4   2.4
  9250   0.6  33.1  230  11  6   3.8   2.1 |  -0.0  32.0  225  10  5   2.8   1.5
  9000   0.8  33.4  230   9  5   2.8   1.5 |   0.1  32.2  220   9  4   2.1   1.1
  8750   1.1  34.0  225   8  4   3.9   2.1 |   0.3  32.5  220   8  4   2.4   1.3
  8500   1.4  34.5  220   6  3   1.3   0.7 |   0.5  32.9  220   7  3   1.4   0.8
  8250   1.3  34.3  220   5  3  -2.7  -1.5 |   0.6  33.1  220   5  3   1.1   0.6
  8000   1.1  34.0  210   4  2  -2.0  -1.1 |   0.6  33.1  220   4  2  -0.5  -0.3
  7750   1.0  33.8  200   3  2  -4.4  -2.4 |   0.7  33.3  220   2  1   5.7   3.1
  7500   0.4  32.7  195   2  1  -9.1  -5.0 |   1.4  34.5  200   1  1   9.0   4.9
  7250  -0.3  31.5  220   2  1 -10.3  -5.7 |   1.9  35.4  180   1  1   4.2   2.3
  7000  -1.1  30.0  250   2  1  -9.6  -5.3 |   2.3  36.1  155   1  1   8.3   4.6
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/14/2017 at 1400 MST          |       01/14/2017 at 1700 MST
                                           |
K index... +20.9  LI... +0.3               | K index... +19.7  LI... -0.0
CAPE... 0.0  CIN... -0.5                   | CAPE... 0.0  CIN... -0.6
                                           |
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 -62.4 -80.3  255  31 16   1.1   0.6 | -62.7 -80.9  255  29 15   1.3   0.7
 45000 -60.8 -77.4  245  39 20   1.0   0.6 | -60.7 -77.3  245  37 19   1.2   0.6
 40000 -59.5 -75.1  230  65 33   0.8   0.4 | -59.9 -75.8  235  63 33   0.5   0.3
 38000 -58.2 -72.8  230  70 36   3.3   1.8 | -58.5 -73.3  230  68 35   3.5   1.9
 36000 -56.2 -69.2  230  71 36   3.3   1.8 | -56.4 -69.5  230  67 35   3.5   1.9
 34000 -53.6 -64.5  230  71 37   7.5   4.1 | -53.8 -64.8  225  67 34   7.3   4.0
 32000 -49.1 -56.4  235  70 36   7.5   4.1 | -49.4 -56.9  230  67 34   7.3   4.0
 30000 -44.7 -48.5  235  67 35   7.3   4.0 | -44.9 -48.8  230  65 34   8.5   4.7
 29000 -42.5 -44.5  235  64 33   7.4   4.0 | -42.3 -44.1  230  63 32   8.6   4.7
 28000 -39.7 -39.5  230  60 31   7.4   4.0 | -39.7 -39.5  230  60 31   8.6   4.7
 27000 -37.5 -35.5  230  57 30   7.5   4.1 | -36.7 -34.1  230  57 29   6.4   3.5
 26000 -35.3 -31.5  230  55 28   7.5   4.1 | -34.7 -30.5  230  54 28   6.7   3.6
 25000 -33.0 -27.4  225  53 27   7.5   4.1 | -32.7 -26.9  225  52 27   6.7   3.7
 24000 -30.8 -23.4  225  51 26   8.2   4.5 | -30.6 -23.1  225  50 26   8.2   4.5
 23000 -28.3 -18.9  225  47 24   8.4   4.6 | -28.1 -18.6  225  48 25   8.6   4.7
 22000 -25.8 -14.4  225  42 22   8.4   4.6 | -25.6 -14.1  230  46 23   8.6   4.7
 21000 -23.4 -10.1  225  39 20   7.4   4.0 | -23.1  -9.6  230  43 22   6.8   3.8
 20000 -21.1  -6.0  230  40 21   7.5   4.1 | -21.1  -6.0  230  40 20   7.0   3.8
 19500 -20.0  -4.0  230  41 21   7.5   4.1 | -20.0  -4.0  235  38 20   7.0   3.8
 19000 -18.9  -2.0  230  41 21   7.5   4.1 | -19.0  -2.2  235  37 19   7.0   3.8
 18500 -17.8  -0.0  235  42 22   7.4   4.0 | -17.9  -0.2  235  35 18   7.4   4.1
 18000 -16.8   1.8  235  42 21   7.4   4.1 | -16.8   1.8  240  34 18   7.4   4.1
 17500 -15.7   3.7  235  41 21   7.6   4.2 | -15.8   3.6  240  33 17   7.6   4.2
 17000 -14.5   5.9  235  41 21   7.9   4.3 | -14.6   5.7  240  32 17   7.9   4.3
 16500 -13.4   7.9  240  40 21   7.9   4.3 | -13.4   7.9  240  31 16   7.9   4.3
 16000 -12.3   9.9  240  40 20   7.7   4.2 | -12.3   9.9  245  30 16   8.1   4.5
 15500 -11.1  12.0  240  39 20   7.8   4.3 | -11.1  12.0  245  29 15   8.2   4.5
 15000 -10.0  14.0  240  38 20   7.1   3.9 |  -9.9  14.2  245  28 14   7.7   4.2
 14500  -9.0  15.8  240  37 19   7.1   3.9 |  -8.8  16.2  245  27 14   7.7   4.2
 14000  -7.5  18.5  235  35 18   6.4   3.5 |  -7.7  18.1  245  25 13   7.3   4.0
 13500  -6.6  20.1  235  32 17   6.6   3.6 |  -6.2  20.8  240  24 12   7.2   3.9
 13000  -5.7  21.7  235  30 15   5.7   3.1 |  -5.2  22.6  240  23 12   6.3   3.5
 12500  -4.9  23.2  235  26 13   5.8   3.2 |  -4.3  24.3  235  21 11   6.6   3.6
 12000  -4.0  24.8  230  22 12   5.1   2.8 |  -3.4  25.9  235  19 10   4.9   2.7
 11750  -3.7  25.3  230  21 11   4.5   2.5 |  -3.1  26.4  235  18  9   4.9   2.7
 11500  -3.3  26.1  230  19 10   5.0   2.7 |  -2.7  27.1  235  16  8   5.2   2.9
 11250  -3.0  26.6  230  17  9   3.8   2.1 |  -2.4  27.7  230  15  8   4.0   2.2
 11000  -2.8  27.0  225  16  8   3.8   2.1 |  -2.1  28.2  230  14  7   3.2   1.8
 10750  -2.4  27.7  225  14  7   5.0   2.7 |  -1.9  28.6  225  13  6   3.7   2.0
 10500  -2.1  28.2  220  13  7   4.8   2.6 |  -1.6  29.1  220  11  6   4.0   2.2
 10250  -1.7  28.9  220  11  6   4.3   2.4 |  -1.3  29.7  215  10  5   2.4   1.3
 10000  -1.4  29.5  215  10  5   4.1   2.2 |  -1.2  29.8  210  10  5   0.9   0.5
  9750  -1.1  30.0  210   9  5   5.0   2.8 |  -1.1  30.0  205   9  5   1.7   0.9
  9500  -0.7  30.7  205   9  4   5.1   2.8 |  -1.0  30.2  195   9  4   1.8   1.0
  9250  -0.4  31.3  200   8  4   3.8   2.1 |  -0.9  30.4  190   8  4   2.2   1.2
  9000  -0.2  31.6  195   7  4   2.6   1.4 |  -0.7  30.7  185   8  4   2.8   1.5
  8750   0.1  32.2  185   6  3   4.4   2.4 |  -0.5  31.1  180   7  4   1.4   0.8
  8500   0.5  32.9  175   6  3   6.2   3.4 |  -0.4  31.3  175   7  3   1.0   0.5
  8250   0.9  33.6  165   6  3   6.5   3.6 |  -0.3  31.5  175   6  3   3.0   1.6
  8000   1.4  34.5  155   6  3   6.0   3.3 |  -0.0  32.0  170   6  3   1.9   1.1
  7750   1.9  35.4  150   6  3   8.8   4.8 |   0.2  32.4  165   6  3   6.6   3.6
  7500   2.7  36.9  145   6  3   9.8   5.4 |   0.8  33.4  155   6  3   3.6   2.0
  7250   3.3  37.9  145   6  3   7.1   3.9 |   0.6  33.1  155   5  3  -4.9  -2.7
  7000   3.9  39.0  145   6  3   9.4   5.2 |   0.4  32.7  155   4  2   2.0   1.1
  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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