Soaring Guidance
Issued by NWS Pueblo, CO

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000
UXUS97 KPUB 161111
SRGPUB

Soaring Forecast
National Weather Service Pueblo, Colorado
0411 MST Monday, January 16, 2017

This forecast is for Monday, January 16, 2017:

If the trigger temperature of 40.6 F/4.8 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 0 ft/min (0.0 m/s)
   Maximum height of thermals.................. 8962 ft MSL (2204 ft AGL)

Forecast maximum temperature................... 31.0 F/-1.0 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................. None
Thermal soaring outlook for Tuesday 01/17...... Poor

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

Remarks...

Sunrise/Sunset.................... 07:15:29 / 17:01:28 MST
Total possible sunshine........... 9 hr 45 min 59 sec (585 min 59 sec)
Altitude of sun at 12:08:52 MST... 30.33 degrees

Upper air data from numerical model forecast valid on 01/16/2017 at 0500 MST

Freezing level.................. Entire airmass below 32 F / 0 C
Convective condensation level... 15000 ft MSL (8242 ft AGL)
Lifted condensation level....... 9218 ft MSL (2460 ft AGL)
Lifted index.................... +12.5
K index......................... +16.9

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  -59.3 -74.7   260   23   12   3.2   1.8      M     M       M      M    M
 45000  -54.5 -66.1   250   29   15   3.5   1.9      M     M       M      M    M
 40000  -54.3 -65.7   260   21   11   0.0   0.0      M     M       M      M    M
 38000  -54.7 -66.5   255   15    8  -2.1  -1.2      M     M       M      M    M
 36000  -56.0 -68.8   195   12    6  -2.2  -1.2      M     M       M      M    M
 34000  -56.7 -70.1   155   21   11   9.1   5.0      M     M       M      M    M
 32000  -51.4 -60.5   155   17    9   9.0   4.9      M     M       M      M    M
 30000  -45.9 -50.6   150   13    7   9.5   5.2   23.8  74.8    18.6      M    M
 29000  -43.1 -45.6   140   13    7   9.5   5.2   23.5  74.4    18.7      M    M
 28000  -40.2 -40.4   130   13    7   9.5   5.2   23.4  74.2    18.8      M    M
 27000  -37.4 -35.3   120   14    7   9.5   5.2   23.5  74.3    19.1      M    M
 26000  -34.7 -30.5   115   14    7   8.6   4.7   23.0  73.5    19.0      M    M
 25000  -32.2 -26.0   105   14    7   8.7   4.8   22.6  72.7    18.8      M    M
 24000  -29.6 -21.3   095   15    8   8.8   4.8   22.3  72.1    18.8      M    M
 23000  -27.2 -17.0   095   15    8   7.8   4.3   21.7  71.0    18.4      M    M
 22000  -24.9 -12.8   090   15    8   7.8   4.3   20.9  69.7    18.0      M    M
 21000  -22.6  -8.7   090   14    7   7.7   4.2   20.3  68.6    17.7      M    M
 20000  -20.4  -4.7   090   13    7   7.0   3.9   19.3  66.8    17.0      M    M
 19500  -19.4  -2.9   090   13    7   7.0   3.9   18.9  65.9    16.7      M    M
 19000  -18.4  -1.1   085   12    6   7.1   3.9   18.4  65.1    16.3      M    M
 18500  -17.3   0.9   085   12    6   7.1   3.9   18.0  64.4    16.0      M    M
 18000  -16.3   2.7   090   11    6   6.4   3.5   17.5  63.5    15.7      M    M
 17500  -15.4   4.3   090   11    6   6.5   3.6   16.9  62.5    15.3      M    M
 17000  -14.4   6.1   095   11    6   6.6   3.6   16.4  61.6    14.8      M    M
 16500  -13.4   7.9   090   11    6   6.7   3.7   15.9  60.6    14.4      M    M
 16000  -12.0  10.4   080   11    6   5.8   3.2   15.1  59.2    13.8      M    M
 15500  -11.2  11.8   070   12    6   5.5   3.0   14.4  57.9    13.2      M    M
 15000  -10.4  13.3   060   13    7   5.3   2.9   13.7  56.7    12.6      M    M
 14500   -9.6  14.7   050   14    7   4.8   2.7   12.9  55.2    12.0      M    M
 14000   -8.9  16.0   045   15    8   4.7   2.6   12.1  53.8    11.3      M    M
 13500   -8.4  16.9   040   16    8   3.5   1.9   11.2  52.1    10.4      M    M
 13000   -7.8  18.0   035   18    9   3.6   2.0   10.2  50.3     9.6      M    M
 12500   -7.3  18.9   030   20   10   3.4   1.9    9.2  48.5     8.7      M    M
 12000   -6.9  19.6   030   22   11   2.4   1.3    8.1  46.6     7.7      M    M
 11750   -6.7  19.9   025   22   12   2.3   1.3    7.5  45.6     7.2      M    M
 11500   -6.5  20.3   025   23   12   2.5   1.4    7.0  44.5     6.6      M    M
 11250   -6.3  20.7   020   24   12   2.5   1.4    6.4  43.5     6.1      M    M
 11000   -6.1  21.0   020   25   13   2.3   1.2    5.8  42.5     5.6      M    M
 10750   -6.0  21.2   015   26   13   1.9   1.0    5.2  41.4     5.0      M    M
 10500   -5.9  21.4   015   27   14   1.7   0.9    4.6  40.2     4.4      M    M
 10250   -5.7  21.7   010   28   14   2.0   1.1    4.0  39.1     3.8      M    M
 10000   -5.6  21.9   010   29   15   0.9   0.5    3.3  38.0     3.3      M    M
  9750   -5.6  21.9   005   31   16  -1.1  -0.6    2.6  36.6     2.5      M    M
  9500   -5.7  21.7   360   32   17  -1.5  -0.8    1.7  35.1     1.7      M    M
  9250   -5.8  21.6   360   33   17  -1.3  -0.7    0.8  33.5     0.9      M    M
  9000   -5.9  21.4   355   35   18  -1.8  -1.0   -0.0  32.0     0.0      M    M
  8750   -6.0  21.2   355   35   18   0.9   0.5   -0.8  30.5    -0.8    260  1.3
  8500   -5.8  21.6   355   35   18   3.5   1.9   -1.4  29.6    -1.3    246  1.3
  8250   -5.5  22.1   355   34   17   3.1   1.7   -1.9  28.7    -1.8    232  1.2
  8000   -5.2  22.6   350   32   17   5.2   2.8   -2.3  27.9    -2.2    216  1.1
  7750   -4.8  23.4   350   29   15   6.8   3.7   -2.6  27.4    -2.5    195  1.0
  7500   -4.3  24.3   350   26   13   7.7   4.2   -2.8  27.0    -2.7    172  0.9
  7250   -3.7  25.3   345   22   12   5.7   3.1   -2.9  26.7    -2.9    149  0.8
  7000   -3.5  25.7   345   20   10  -0.2  -0.1   -2.9  26.7    -2.9    135  0.7
  6750      M     M     M    M    M     M     M      M     M       M      M    M

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

           01/16/2017 at 0800 MST          |       01/16/2017 at 1100 MST
                                           |
K index... +16.3  LI... +2.2               | K index... +15.6  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 -58.8 -73.8  260  26 13   3.2   1.8 | -59.4 -74.9  255  26 14   3.3   1.8
 45000 -54.0 -65.2  260  29 15   3.6   2.0 | -54.5 -66.1  255  29 15   3.8   2.1
 40000 -55.1 -67.2  270  14  7  -1.0  -0.5 | -55.4 -67.7  245  15  8  -0.8  -0.5
 38000 -55.8 -68.4  255   7  4  -1.1  -0.6 | -55.9 -68.6  220  11  6  -0.9  -0.5
 36000 -56.4 -69.5  170  10  5  -1.1  -0.6 | -56.5 -69.7  180  13  7  -0.9  -0.5
 34000 -56.8 -70.2  150  21 11   5.4   3.0 | -56.7 -70.1  160  18  9   5.9   3.3
 32000 -51.8 -61.2  150  18  9   8.4   4.6 | -51.8 -61.2  145  16  8   8.2   4.5
 30000 -46.7 -52.1  150  14  7   9.4   5.1 | -46.8 -52.2  135  14  7   9.7   5.3
 29000 -43.9 -47.0  145  13  7   9.4   5.1 | -43.9 -47.0  130  13  7   9.6   5.3
 28000 -41.1 -42.0  135  11  6   9.4   5.2 | -40.3 -40.5  130  12  6   9.6   5.3
 27000 -37.6 -35.7  120  10  5   9.3   5.1 | -37.4 -35.3  130  11  6   9.3   5.1
 26000 -34.9 -30.8  120  11  6   8.9   4.9 | -34.8 -30.6  125  11  5   8.8   4.8
 25000 -32.3 -26.1  115  12  6   8.9   4.9 | -32.2 -26.0  120  10  5   8.8   4.8
 24000 -29.6 -21.3  115  13  7   9.0   4.9 | -29.6 -21.3  110  10  5   8.8   4.8
 23000 -27.3 -17.1  110  14  7   7.8   4.3 | -27.3 -17.1  100  10  5   7.5   4.1
 22000 -25.0 -13.0  100  14  7   7.8   4.3 | -25.0 -13.0  090  11  6   7.6   4.2
 21000 -22.7  -8.9  095  15  8   7.6   4.2 | -22.8  -9.0  085  12  6   7.6   4.1
 20000 -20.5  -4.9  090  14  7   7.3   4.0 | -20.6  -5.1  085  12  6   7.6   4.1
 19500 -19.4  -2.9  090  14  7   7.3   4.0 | -19.5  -3.1  080  12  6   7.6   4.2
 19000 -18.4  -1.1  090  14  7   7.3   4.0 | -18.4  -1.1  080  11  6   7.6   4.2
 18500 -17.3   0.9  085  13  7   7.3   4.0 | -17.2   1.0  080  11  6   7.5   4.1
 18000 -16.2   2.8  085  13  7   7.0   3.9 | -16.2   2.8  080  11  6   6.8   3.7
 17500 -15.2   4.6  085  12  6   7.1   3.9 | -15.2   4.6  085  11  6   6.9   3.8
 17000 -14.2   6.4  085  12  6   6.7   3.7 | -14.2   6.4  085  11  5   6.2   3.4
 16500 -13.2   8.2  085  11  6   6.5   3.6 | -13.3   8.1  080  10  5   6.1   3.3
 16000 -12.3   9.9  085  10  5   6.3   3.5 | -12.4   9.7  075  10  5   5.8   3.2
 15500 -11.4  11.5  075  10  5   5.7   3.1 | -11.7  10.9  065  10  5   5.4   2.9
 15000 -10.6  12.9  070  10  5   5.8   3.2 | -10.9  12.4  060  10  5   5.3   2.9
 14500  -9.8  14.4  060  11  6   4.5   2.5 | -10.3  13.5  050  11  6   3.1   1.7
 14000  -8.8  16.2  050  13  7   4.4   2.4 |  -9.5  14.9  040  14  7   3.4   1.8
 13500  -8.3  17.1  045  15  8   3.8   2.1 |  -9.0  15.8  040  17  9   3.4   1.9
 13000  -7.7  18.1  040  17  9   3.7   2.0 |  -8.5  16.7  035  20 10   3.4   1.9
 12500  -7.3  18.9  035  20 10   2.6   1.4 |  -8.0  17.6  030  22 11   3.4   1.9
 12000  -6.9  19.6  030  22 12   1.3   0.7 |  -7.5  18.5  030  24 12   3.2   1.7
 11750  -6.8  19.8  025  24 12   2.1   1.2 |  -7.3  18.9  025  25 13   2.6   1.4
 11500  -6.6  20.1  025  25 13   2.7   1.5 |  -7.1  19.2  025  26 13   2.4   1.3
 11250  -6.4  20.5  020  27 14   2.7   1.5 |  -6.9  19.6  020  27 14   2.7   1.5
 11000  -6.2  20.8  020  28 15   2.1   1.2 |  -6.8  19.8  020  28 15   1.7   0.9
 10750  -6.1  21.0  015  29 15   0.7   0.4 |  -6.7  19.9  020  29 15   1.0   0.6
 10500  -6.1  21.0  015  31 16   0.3   0.2 |  -6.6  20.1  020  30 16   1.6   0.9
 10250  -6.1  21.0  010  32 16   0.6   0.3 |  -6.5  20.3  015  31 16   1.4   0.8
 10000  -6.0  21.2  010  33 17  -0.3  -0.1 |  -6.4  20.5  015  32 16   1.5   0.8
  9750  -6.1  21.0  005  35 18  -2.7  -1.5 |  -6.3  20.7  015  33 17   0.8   0.4
  9500  -6.4  20.5  005  36 19  -3.4  -1.9 |  -6.2  20.8  010  34 17   0.2   0.1
  9250  -6.6  20.1  360  38 19  -3.6  -2.0 |  -6.2  20.8  010  35 18   0.5   0.3
  9000  -6.8  19.8  360  39 20  -2.1  -1.1 |  -6.2  20.8  010  35 18   0.2   0.1
  8750  -6.8  19.8  355  39 20   3.1   1.7 |  -6.1  21.0  360  35 18   3.3   1.8
  8500  -6.5  20.3  355  38 20   5.4   2.9 |  -5.7  21.7  360  34 17   5.8   3.2
  8250  -6.1  21.0  350  37 19   5.3   2.9 |  -5.3  22.5  355  33 17   6.2   3.4
  8000  -5.6  21.9  350  36 18   7.4   4.1 |  -4.8  23.4  350  32 16   8.4   4.6
  7750  -5.0  23.0  350  33 17   8.0   4.4 |  -4.1  24.6  350  30 15   8.5   4.7
  7500  -4.5  23.9  345  29 15   8.2   4.5 |  -3.5  25.7  345  27 14   8.0   4.4
  7250  -3.9  25.0  345  26 13   5.8   3.2 |  -3.0  26.6  345  24 12   6.6   3.6
  7000  -3.7  25.3  345  23 12  -0.5  -0.3 |  -2.6  27.3  345  21 11   4.2   2.3
  6750     M     M    M   M  M     M     M |     M     M    M   M  M     M     M

           01/16/2017 at 1400 MST          |       01/16/2017 at 1700 MST
                                           |
K index... +14.3  LI... +3.8               | K index... +14.6  LI... +3.4
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 -59.5 -75.1  255  28 14   3.0   1.6 | -59.2 -74.6  255  27 14   2.9   1.6
 45000 -55.0 -67.0  255  28 15   3.4   1.9 | -54.8 -66.6  250  25 13   3.3   1.8
 40000 -55.5 -67.9  240  20 11  -0.5  -0.3 | -55.4 -67.7  245  17  9  -0.5  -0.3
 38000 -55.9 -68.6  230  17  9  -1.0  -0.5 | -55.8 -68.4  245  13  6  -0.8  -0.4
 36000 -56.5 -69.7  215  12  6  -1.0  -0.5 | -56.3 -69.3  240   8  4  -0.8  -0.4
 34000 -56.8 -70.2  185   9  5   6.5   3.6 | -56.5 -69.7  225   4  2   6.0   3.3
 32000 -51.6 -60.9  155   8  4   8.5   4.7 | -51.8 -61.2  110   1  0   7.8   4.3
 30000 -46.5 -51.7  120   8  4   9.6   5.3 | -47.0 -52.6  065   4  2   9.8   5.4
 29000 -43.6 -46.5  115   8  4   9.5   5.2 | -43.4 -46.1  070   5  2   9.6   5.3
 28000 -40.1 -40.2  110   7  4   9.5   5.2 | -40.5 -40.9  075   5  3   9.7   5.3
 27000 -37.3 -35.1  100   7  4   9.1   5.0 | -37.6 -35.7  080   6  3   9.2   5.1
 26000 -34.8 -30.6  100   8  4   8.4   4.6 | -35.1 -31.2  085   7  4   8.6   4.7
 25000 -32.2 -26.0  095   9  4   8.4   4.6 | -32.5 -26.5  090   9  5   8.6   4.7
 24000 -29.7 -21.5  090   9  5   8.4   4.6 | -29.9 -21.8  090  10  5   8.5   4.7
 23000 -27.4 -17.3  085  10  5   7.8   4.3 | -27.6 -17.7  090  11  6   7.9   4.3
 22000 -25.1 -13.2  080  10  5   7.8   4.3 | -25.2 -13.4  085  11  6   7.9   4.3
 21000 -22.8  -9.0  075  11  6   7.6   4.2 | -22.9  -9.2  085  12  6   7.6   4.1
 20000 -20.6  -5.1  080  11  6   7.4   4.1 | -20.8  -5.4  085  12  6   7.2   4.0
 19500 -19.5  -3.1  080  12  6   7.4   4.1 | -19.7  -3.5  090  13  7   7.2   4.0
 19000 -18.4  -1.1  080  12  6   7.5   4.1 | -18.6  -1.5  090  13  7   7.2   4.0
 18500 -17.3   0.9  080  12  6   7.4   4.1 | -17.6   0.3  090  13  7   7.1   3.9
 18000 -16.2   2.8  085  12  6   7.2   4.0 | -16.6   2.1  095  14  7   6.8   3.7
 17500 -15.2   4.6  085  12  6   7.4   4.0 | -15.6   3.9  090  14  7   6.9   3.8
 17000 -14.2   6.4  085  12  6   5.7   3.1 | -14.6   5.7  090  14  7   5.8   3.2
 16500 -13.4   7.9  075  12  6   5.5   3.0 | -13.8   7.2  085  13  7   5.7   3.1
 16000 -12.6   9.3  070  12  6   4.9   2.7 | -13.0   8.6  085  13  7   5.2   2.9
 15500 -12.0  10.4  065  12  6   4.0   2.2 | -12.3   9.9  075  13  7   4.8   2.6
 15000 -11.4  11.5  055  13  7   4.0   2.2 | -11.6  11.1  070  13  7   4.7   2.6
 14500 -10.8  12.6  050  14  7   3.7   2.0 | -10.9  12.4  060  14  7   4.1   2.3
 14000 -10.0  14.0  040  18  9   3.5   1.9 | -10.0  14.0  055  15  8   4.0   2.2
 13500  -9.5  14.9  035  19 10   3.3   1.8 |  -9.5  14.9  045  16  8   3.8   2.1
 13000  -9.0  15.8  035  20 11   3.1   1.7 |  -8.9  16.0  040  16  8   3.5   1.9
 12500  -8.6  16.5  030  22 11   2.7   1.5 |  -8.5  16.7  035  17  9   2.9   1.6
 12000  -8.2  17.2  025  24 12   3.0   1.6 |  -8.0  17.6  035  18  9   2.4   1.3
 11750  -8.0  17.6  025  25 13   3.1   1.7 |  -7.9  17.8  030  19 10   1.8   1.0
 11500  -7.7  18.1  025  26 13   3.1   1.7 |  -7.8  18.0  030  20 10   1.8   1.0
 11250  -7.5  18.5  025  27 14   3.1   1.7 |  -7.6  18.3  025  21 11   1.6   0.9
 11000  -7.3  18.9  025  28 14   3.2   1.7 |  -7.5  18.5  025  22 11   2.6   1.4
 10750  -7.0  19.4  025  28 15   3.0   1.7 |  -7.3  18.9  025  23 12   2.5   1.4
 10500  -6.8  19.8  020  29 15   2.7   1.5 |  -7.1  19.2  020  24 12   1.5   0.8
 10250  -6.6  20.1  020  29 15   3.0   1.7 |  -7.0  19.4  015  24 13   1.5   0.8
 10000  -6.4  20.5  020  29 15   2.0   1.1 |  -6.9  19.6  015  25 13   2.9   1.6
  9750  -6.3  20.7  015  29 15   1.2   0.7 |  -6.6  20.1  010  26 13   3.6   2.0
  9500  -6.2  20.8  015  29 15   1.5   0.8 |  -6.4  20.5  010  26 14   3.0   1.6
  9250  -6.1  21.0  010  29 15   1.7   0.9 |  -6.1  21.0  005  27 14   3.0   1.7
  9000  -6.0  21.2  010  29 15   1.6   0.9 |  -6.0  21.2  005  27 14   1.0   0.5
  8750  -5.8  21.6  005  29 15   4.4   2.4 |  -5.9  21.4  360  27 14   2.9   1.6
  8500  -5.3  22.5  360  28 14   6.6   3.6 |  -5.5  22.1  360  27 14   5.4   3.0
  8250  -4.9  23.2  355  27 14   7.0   3.8 |  -5.2  22.6  355  26 14   6.0   3.3
  8000  -4.3  24.3  350  26 13   8.5   4.7 |  -4.7  23.5  355  25 13   7.2   4.0
  7750  -3.7  25.3  350  24 12   8.5   4.7 |  -4.1  24.6  350  23 12   7.6   4.2
  7500  -3.1  26.4  350  21 11   8.1   4.4 |  -3.6  25.5  350  20 10   7.3   4.0
  7250  -2.5  27.5  345  19 10   6.5   3.6 |  -3.1  26.4  350  18  9   4.5   2.4
  7000  -2.2  28.0  345  17  9   4.5   2.5 |  -2.9  26.8  345  16  8   2.3   1.3
  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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