Soaring Guidance
Issued by NWS Pueblo, CO

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UXUS97 KPUB 121133
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0432 MST Thursday, January 12, 2017

This forecast is for Thursday, January 12, 2017:

If the trigger temperature of 43.0 F/6.1 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 104 ft/min (0.5 m/s)
   Maximum height of thermals.................. 8514 ft MSL (1756 ft AGL)

Forecast maximum temperature................... 40.0 F/4.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7357 ft MSL (600 ft AGL)
Thermal soaring outlook for Friday 01/13....... Poor

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

Remarks...

Sunrise/Sunset.................... 07:16:52 / 16:58:19 MST
Total possible sunshine........... 9 hr 41 min 28 sec (581 min 28 sec)
Altitude of sun at 12:07:28 MST... 29.60 degrees

Upper air data from numerical model forecast valid on 01/12/2017 at 0500 MST

Freezing level.................. 7059 ft MSL (301 ft AGL)
Additional freezing level....... 8782 ft MSL (2024 ft AGL)
Convective condensation level... 16702 ft MSL (9944 ft AGL)
Lifted condensation level....... 13148 ft MSL (6390 ft AGL)
Lifted index.................... +8.6
K index......................... -9.3

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  -66.1 -87.0   255   74   38   2.9   1.6      M     M       M      M    M
 45000  -61.6 -78.9   260   81   42   2.8   1.5      M     M       M      M    M
 40000  -60.9 -77.6   260   89   46   0.2   0.1      M     M       M      M    M
 38000  -60.3 -76.5   260   93   48   3.0   1.7      M     M       M      M    M
 36000  -58.4 -73.1   265   97   50   3.1   1.7      M     M       M      M    M
 34000  -56.5 -69.7   265  101   52   4.2   2.3      M     M       M      M    M
 32000  -52.0 -61.6   265   97   50   7.9   4.3      M     M       M      M    M
 30000  -46.6 -51.9   260   92   47   8.4   4.6   23.1  73.6    14.3      M    M
 29000  -44.2 -47.6   260   90   46   8.3   4.5   22.4  72.3    13.9      M    M
 28000  -41.7 -43.1   260   87   45   8.3   4.5   21.8  71.2    13.6      M    M
 27000  -39.2 -38.6   260   85   44   8.2   4.5   21.3  70.4    13.4      M    M
 26000  -36.7 -34.1   260   83   43   8.4   4.6   20.8  69.4    13.1      M    M
 25000  -34.2 -29.6   260   80   41   8.4   4.6   20.3  68.5    12.8      M    M
 24000  -31.7 -25.1   260   78   40   8.5   4.7   19.9  67.7    12.6      M    M
 23000  -29.4 -20.9   260   75   38   7.0   3.8   19.0  66.2    12.1      M    M
 22000  -27.3 -17.1   260   71   37   7.0   3.8   18.0  64.4    11.4      M    M
 21000  -25.3 -13.5   260   68   35   7.0   3.8   17.1  62.8    10.7      M    M
 20000  -23.4 -10.1   265   64   33   6.2   3.4   15.8  60.5     9.8      M    M
 19500  -22.4  -8.3   265   62   32   6.2   3.4   15.2  59.4     9.3      M    M
 19000  -21.5  -6.7   270   60   31   6.2   3.4   14.6  58.3     8.8      M    M
 18500  -20.6  -5.1   270   58   30   5.9   3.2   14.1  57.3     8.4      M    M
 18000  -19.5  -3.1   270   54   28   8.7   4.8   13.7  56.6     8.1      M    M
 17500  -18.2  -0.8   270   48   25   8.4   4.6   13.4  56.2     7.9      M    M
 17000  -16.9   1.6   270   43   22   7.8   4.3   13.2  55.8     7.8      M    M
 16500  -15.8   3.6   265   39   20   7.4   4.1   12.8  55.1     7.5      M    M
 16000  -14.7   5.5   265   36   19   7.0   3.8   12.4  54.4     7.2      M    M
 15500  -13.9   7.0   265   34   18   4.5   2.4   11.7  53.1     6.5      M    M
 15000  -12.9   8.8   265   33   17   4.7   2.6   10.5  50.8     5.4      M    M
 14500  -12.2  10.0   265   31   16   4.9   2.7    9.6  49.3     4.7      M    M
 14000  -11.5  11.3   265   29   15   5.4   3.0    8.8  47.9     4.0      M    M
 13500  -10.5  13.1   265   26   13   7.1   3.9    8.3  47.0     3.5      M    M
 13000   -9.4  15.1   265   22   11   7.2   4.0    7.9  46.2     3.1      M    M
 12500   -8.3  17.1   265   22   11   8.6   4.7    7.6  45.7     2.8      M    M
 12000   -7.1  19.2   270   24   13   6.8   3.7    7.3  45.1     2.5      M    M
 11750   -6.6  20.1   275   25   13   7.2   4.0    7.1  44.7     2.3      M    M
 11500   -6.1  21.0   275   26   13   7.4   4.0    6.9  44.4     2.1      M    M
 11250   -5.5  22.1   275   26   14   7.3   4.0    6.7  44.0     1.9      M    M
 11000   -5.0  23.0   280   27   14   7.0   3.9    6.5  43.7     1.8      M    M
 10750   -4.5  23.9   280   27   14   7.3   4.0    6.3  43.3     1.5      M    M
 10500   -3.9  25.0   280   27   14   7.8   4.3    6.1  43.0     1.4      M    M
 10250   -3.4  25.9   280   28   14   7.7   4.2    6.0  42.7     1.2      M    M
 10000   -2.8  27.0   285   29   15   7.7   4.2    5.8  42.4     1.0      M    M
  9750   -2.2  28.0   285   29   15   8.1   4.4    5.6  42.2     0.9      M    M
  9500   -1.6  29.1   285   28   15   8.3   4.6    5.5  42.0     0.7      M    M
  9250   -1.0  30.2   285   28   15   8.4   4.6    5.4  41.8     0.6      M    M
  9000   -0.4  31.3   285   28   15   8.1   4.4    5.3  41.6     0.5      M    M
  8750    0.1  32.2   285   27   14   6.1   3.4    5.1  41.2     0.3      M    M
  8500    0.5  32.9   285   26   13   5.2   2.8    4.8  40.6    -0.0    101  0.5
  8250    0.9  33.6   285   25   13   5.2   2.8    4.5  40.0    -0.4     83  0.4
  8000    1.1  34.0   280   25   13   0.2   0.1    4.0  39.1    -0.9     68  0.3
  7750    0.9  33.6   280   23   12  -2.4  -1.3    3.1  37.5    -1.8     66  0.3
  7500    0.9  33.6   280   20   10   2.1   1.2    2.3  36.2    -2.6     60  0.3
  7250    0.9  33.6   280   16    8  -5.5  -3.0    1.6  34.9    -3.3     52  0.3
  7000   -0.3  31.5   280   12    6 -24.8 -13.6    0.3  32.5    -4.7     80  0.4
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/12/2017 at 0800 MST          |       01/12/2017 at 1100 MST
                                           |
K index... +1.9  LI... +3.6                | K index... +9.1  LI... +2.1
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 -65.9 -86.6  255  87 45   1.0   0.6 | -63.5 -82.3  260  83 43   0.4   0.2
 45000 -64.4 -83.9  255  89 46   1.0   0.6 | -62.8 -81.0  255  96 49   0.4   0.2
 40000 -64.3 -83.7  260  99 51  -0.1  -0.1 | -64.0 -83.2  250 105 54  -0.9  -0.5
 38000 -63.3 -81.9  260 101 52   5.8   3.2 | -63.4 -82.1  250 107 55   5.3   2.9
 36000 -59.8 -75.6  255 100 52   5.8   3.2 | -60.2 -76.4  250 109 56   5.4   3.0
 34000 -56.3 -69.3  255 100 51   7.0   3.8 | -56.9 -70.4  245 110 57   6.8   3.7
 32000 -51.6 -60.9  255  95 49   7.9   4.3 | -51.9 -61.4  245 103 53   8.5   4.7
 30000 -46.9 -52.4  255  90 47   8.4   4.6 | -46.0 -50.8  245  94 48   9.8   5.4
 29000 -44.4 -47.9  250  86 44   8.4   4.6 | -43.1 -45.6  245  90 46   9.7   5.3
 28000 -41.2 -42.2  250  81 42   8.4   4.6 | -40.2 -40.4  245  85 44   9.7   5.3
 27000 -38.7 -37.7  250  77 40   8.4   4.6 | -37.3 -35.1  245  81 42   9.6   5.3
 26000 -36.2 -33.2  250  73 38   8.5   4.7 | -35.0 -31.0  245  79 41   7.4   4.0
 25000 -33.7 -28.7  245  69 35   8.5   4.7 | -32.8 -27.0  245  77 40   7.4   4.0
 24000 -31.1 -24.0  245  64 33   8.8   4.8 | -30.6 -23.1  245  76 39   7.7   4.2
 23000 -29.0 -20.2  245  60 31   6.6   3.6 | -29.0 -20.2  245  71 36   4.4   2.4
 22000 -27.0 -16.6  250  56 29   6.6   3.6 | -27.7 -17.9  245  64 33   4.4   2.4
 21000 -25.1 -13.2  250  52 27   6.6   3.6 | -26.4 -15.5  245  58 30   4.5   2.5
 20000 -23.1  -9.6  255  48 25   6.5   3.5 | -24.9 -12.8  240  53 27   5.2   2.9
 19500 -22.2  -8.0  255  46 24   6.5   3.5 | -24.1 -11.4  240  50 26   5.2   2.9
 19000 -21.2  -6.2  255  44 23   6.5   3.6 | -23.4 -10.1  240  48 25   5.2   2.9
 18500 -20.3  -4.5  255  43 22   6.5   3.6 | -22.6  -8.7  240  45 23   5.3   2.9
 18000 -19.3  -2.7  255  40 21   6.9   3.8 | -21.7  -7.1  240  44 22   6.8   3.7
 17500 -18.2  -0.8  255  38 20   6.8   3.7 | -20.7  -5.3  245  42 22   6.6   3.6
 17000 -17.2   1.0  250  36 19   7.1   3.9 | -19.6  -3.3  245  41 21   7.4   4.1
 16500 -16.1   3.0  250  34 18   7.1   3.9 | -18.5  -1.3  245  39 20   7.6   4.2
 16000 -15.1   4.8  250  32 17   7.0   3.8 | -17.4   0.7  245  37 19   7.7   4.2
 15500 -14.1   6.6  250  30 16   6.8   3.7 | -16.2   2.8  250  35 18   7.9   4.3
 15000 -13.1   8.4  245  28 15   6.8   3.7 | -14.5   5.9  250  31 16   7.1   3.9
 14500 -12.0  10.4  240  25 13   7.6   4.2 | -13.4   7.9  250  28 14   6.9   3.8
 14000 -10.3  13.5  225  20 10   7.8   4.3 | -12.4   9.7  255  25 13   7.0   3.8
 13500  -9.1  15.6  240  19 10   8.0   4.4 | -11.4  11.5  255  21 11   7.1   3.9
 13000  -7.9  17.8  255  20 10   7.6   4.2 | -10.3  13.5  255  17  9   7.4   4.1
 12500  -6.8  19.8  260  20 11   7.1   3.9 |  -9.2  15.4  255  15  8   8.1   4.4
 12000  -5.9  21.4  265  22 11   5.6   3.0 |  -8.2  17.2  255  13  7   5.9   3.2
 11750  -5.5  22.1  265  22 11   6.0   3.3 |  -7.7  18.1  250  11  6   6.9   3.8
 11500  -5.0  23.0  270  22 11   6.0   3.3 |  -7.2  19.0  245  10  5   6.9   3.8
 11250  -4.6  23.7  275  22 11   6.0   3.3 |  -6.7  19.9  235   9  4   6.9   3.8
 11000  -4.2  24.4  275  22 11   5.6   3.0 |  -6.2  20.8  225   8  4   6.9   3.8
 10750  -3.8  25.2  280  22 11   5.6   3.1 |  -5.7  21.7  220   7  3   7.0   3.8
 10500  -3.4  25.9  280  21 11   5.9   3.3 |  -5.1  22.8  205   6  3   7.1   3.9
 10250  -2.9  26.8  285  21 11   5.6   3.1 |  -4.6  23.7  185   6  3   7.0   3.9
 10000  -2.5  27.5  290  21 11   6.5   3.6 |  -4.1  24.6  170   7  3   7.0   3.9
  9750  -2.0  28.4  290  20 10   7.1   3.9 |  -3.6  25.5  155   7  4   7.3   4.0
  9500  -1.5  29.3  290  19 10   6.7   3.6 |  -3.0  26.6  150   8  4   7.5   4.1
  9250  -1.0  30.2  295  19 10   6.7   3.7 |  -2.5  27.5  140   8  4   7.3   4.0
  9000  -0.5  31.1  295  18  9   6.7   3.7 |  -1.9  28.6  135   9  4   7.5   4.1
  8750  -0.1  31.8  295  17  9   5.6   3.1 |  -1.4  29.5  130   9  5   6.0   3.3
  8500   0.3  32.5  295  17  9   5.6   3.1 |  -1.1  30.0  125  10  5   4.4   2.4
  8250   0.7  33.3  290  16  8   3.8   2.1 |  -0.7  30.7  120  12  6   5.4   3.0
  8000   0.7  33.3  290  15  8  -1.4  -0.8 |  -0.3  31.5  115  12  6   5.7   3.1
  7750   0.5  32.9  290  14  7  -2.1  -1.1 |   0.1  32.2  115  11  6   6.7   3.7
  7500   0.5  32.9  290  11  6   2.7   1.5 |   0.7  33.3  110  10  5   7.3   4.0
  7250   0.5  32.9  290   8  4  -7.1  -3.9 |   1.1  34.0  110   9  5   4.4   2.4
  7000  -0.9  30.4  290   6  3 -29.3 -16.1 |   1.3  34.3  110   7  3   1.3   0.7
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/12/2017 at 1400 MST          |       01/12/2017 at 1700 MST
                                           |
K index... +11.2  LI... +4.3               | K index... +12.4  LI... +4.7
CAPE... 0.0  CIN... -0.2                   | 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 -62.9 -81.2  260  76 39   1.0   0.6 | -63.3 -81.9  260  68 35   1.3   0.7
 45000 -61.4 -78.5  255  89 46   1.0   0.5 | -61.4 -78.5  260  83 43   1.2   0.6
 40000 -62.7 -80.9  255 101 52  -1.2  -0.6 | -64.2 -83.6  255 104 53  -2.2  -1.2
 38000 -62.5 -80.5  255 104 54   4.4   2.4 | -63.5 -82.3  255 105 54   6.5   3.6
 36000 -59.8 -75.6  255 103 53   4.5   2.5 | -59.7 -75.5  250  96 49   6.4   3.5
 34000 -56.5 -69.7  255 101 52   9.1   5.0 | -55.7 -68.3  245  88 45   8.6   4.7
 32000 -51.0 -59.8  250  98 51   9.1   5.0 | -50.4 -58.7  245  86 44   8.9   4.9
 30000 -45.6 -50.1  250  95 49   8.4   4.6 | -45.1 -49.2  245  85 44   9.0   4.9
 29000 -43.0 -45.4  245  90 46   8.5   4.7 | -42.5 -44.5  245  87 45   8.8   4.8
 28000 -40.5 -40.9  245  85 44   8.5   4.7 | -39.8 -39.6  245  89 46   8.8   4.8
 27000 -37.9 -36.2  245  80 41   8.6   4.7 | -36.5 -33.7  250  92 47   8.4   4.6
 26000 -35.4 -31.7  240  73 38   8.5   4.7 | -34.2 -29.6  250  89 46   7.7   4.2
 25000 -32.8 -27.0  240  66 34   8.5   4.7 | -31.9 -25.4  250  86 44   7.7   4.2
 24000 -30.3 -22.5  245  59 30   8.7   4.8 | -29.6 -21.3  250  83 43   7.7   4.2
 23000 -28.1 -18.6  245  61 31   6.6   3.6 | -27.5 -17.5  250  79 41   7.0   3.9
 22000 -26.1 -15.0  245  66 34   6.6   3.6 | -25.4 -13.7  245  74 38   7.0   3.9
 21000 -24.2 -11.6  250  72 37   6.5   3.6 | -23.4 -10.1  245  69 36   6.6   3.6
 20000 -22.6  -8.7  250  70 36   5.1   2.8 | -21.6  -6.9  250  67 35   5.8   3.2
 19500 -21.8  -7.2  250  67 35   5.1   2.8 | -20.8  -5.4  250  67 34   5.8   3.2
 19000 -21.1  -6.0  250  65 34   5.1   2.8 | -19.9  -3.8  250  66 34   5.8   3.2
 18500 -20.3  -4.5  250  63 33   5.2   2.8 | -19.0  -2.2  250  65 34   5.5   3.0
 18000 -19.6  -3.3  250  61 31   4.3   2.4 | -18.4  -1.1  255  65 33   3.2   1.8
 17500 -19.0  -2.2  245  58 30   4.4   2.4 | -17.9  -0.2  255  64 33   3.2   1.8
 17000 -18.3  -0.9  245  55 28   3.1   1.7 | -17.4   0.7  255  63 32   5.3   2.9
 16500 -17.8  -0.0  240  48 25   2.1   1.2 | -16.5   2.3  255  58 30   5.6   3.1
 16000 -17.3   0.9  240  44 23   5.6   3.1 | -15.7   3.7  255  53 27   5.9   3.2
 15500 -16.4   2.5  235  40 21   6.0   3.3 | -14.8   5.4  250  51 26   6.2   3.4
 15000 -15.5   4.1  235  36 19   6.6   3.6 | -13.9   7.0  250  50 26   5.8   3.2
 14500 -14.5   5.9  230  33 17   7.0   3.8 | -13.3   8.1  245  46 24   2.9   1.6
 14000 -13.4   7.9  225  31 16   6.9   3.8 | -12.6   9.3  235  42 22   4.5   2.5
 13500 -12.5   9.5  220  28 14   6.7   3.7 | -11.7  10.9  225  38 20   5.6   3.1
 13000 -11.5  11.3  215  26 13   7.0   3.8 | -10.9  12.4  215  35 18   6.1   3.3
 12500 -10.4  13.3  210  24 12   7.8   4.3 | -10.0  14.0  210  34 18   6.6   3.6
 12000  -9.5  14.9  205  23 12   4.5   2.5 |  -9.1  15.6  200  33 17   5.6   3.1
 11750  -9.1  15.6  200  22 11   5.7   3.1 |  -8.7  16.3  200  33 17   5.0   2.8
 11500  -8.7  16.3  195  22 11   6.2   3.4 |  -8.3  17.1  195  33 17   5.2   2.9
 11250  -8.2  17.2  190  21 11   6.0   3.3 |  -7.9  17.8  190  33 17   4.8   2.6
 11000  -7.8  18.0  185  21 11   6.5   3.6 |  -7.6  18.3  190  34 17   6.5   3.6
 10750  -7.3  18.9  185  21 11   6.5   3.6 |  -7.0  19.4  190  31 16   6.2   3.4
 10500  -6.8  19.8  180  20 10   6.0   3.3 |  -6.7  19.9  185  30 15   4.1   2.3
 10250  -6.4  20.5  175  20 10   6.1   3.3 |  -6.4  20.5  185  29 15   4.9   2.7
 10000  -5.9  21.4  170  20 10   6.6   3.6 |  -6.1  21.0  185  27 14   2.3   1.2
  9750  -5.4  22.3  170  20 10   5.4   3.0 |  -6.0  21.2  180  23 12  -0.0  -0.0
  9500  -5.1  22.8  165  20 10   4.0   2.2 |  -6.0  21.2  175  20 11   0.2   0.1
  9250  -4.8  23.4  160  20 10   4.5   2.5 |  -6.0  21.2  170  18  9   0.5   0.3
  9000  -4.5  23.9  155  20 10   4.2   2.3 |  -5.9  21.4  160  16  8   1.0   0.6
  8750  -4.1  24.6  150  19 10   5.4   3.0 |  -5.8  21.6  150  15  8   3.1   1.7
  8500  -3.7  25.3  145  18  9   6.4   3.5 |  -5.5  22.1  145  15  8   4.0   2.2
  8250  -3.2  26.2  135  17  9   6.9   3.8 |  -5.2  22.6  135  14  7   6.4   3.5
  8000  -2.7  27.1  135  16  8   7.7   4.2 |  -4.5  23.9  135  14  7   9.6   5.3
  7750  -2.1  28.2  135  14  7   8.1   4.4 |  -3.8  25.2  135  13  7   8.8   4.8
  7500  -1.5  29.3  135  13  7   8.4   4.6 |  -3.2  26.2  135  12  6   7.5   4.1
  7250  -0.9  30.4  130  12  6   7.4   4.1 |  -2.7  27.1  135  11  6   5.2   2.9
  7000  -0.4  31.3  130  11  6   6.5   3.6 |  -2.4  27.7  135  10  5   4.0   2.2
  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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