Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 130051
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1750 MST Friday, February 12, 2016

This forecast is for Saturday, February 13, 2016:

If the trigger temperature of 67.2 F/19.5 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 218 ft/min (1.1 m/s)
   Maximum height of thermals.................. 8500 ft MSL (3193 ft AGL)

Forecast maximum temperature................... 65.0 F/18.8 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................. 7199 ft MSL (1893 ft AGL)
Thermal soaring outlook for Sunday 02/14....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 44979 ft MSL (39672 ft AGL)
Wave soaring outlook for Sunday 02/14.......... Poor

Remarks...

Sunrise/Sunset.................... 06:54:47 / 17:31:41 MST
Total possible sunshine........... 10 hr 36 min 54 sec (636 min 54 sec)
Altitude of sun at 12:13:33 MST... 36.92 degrees

Upper air data from numerical model forecast valid on 02/13/2016 at 0500 MST

Freezing level.................. 5392 ft MSL (85 ft AGL)
Additional freezing level....... 12649 ft MSL (7342 ft AGL)
Convective condensation level... 18795 ft MSL (13488 ft AGL)
Lifted condensation level....... 16466 ft MSL (11159 ft AGL)
Lifted index.................... +3.9
K index......................... -11.8

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  -60.4 -76.7   285   53   28   0.8   0.4      M     M       M      M    M
 45000  -59.3 -74.7   285   83   43  -1.8  -1.0      M     M       M      M    M
 40000  -64.1 -83.4   285   72   37  -3.2  -1.8      M     M       M      M    M
 38000  -62.4 -80.3   280   69   35   7.1   3.9      M     M       M      M    M
 36000  -58.2 -72.8   280   68   35   7.1   3.9      M     M       M      M    M
 34000  -53.1 -63.6   280   66   34   8.5   4.7      M     M       M      M    M
 32000  -48.0 -54.4   280   62   32   8.5   4.7      M     M       M      M    M
 30000  -43.0 -45.4   280   57   29   8.1   4.4   32.2  90.0    10.5      M    M
 29000  -40.5 -40.9   280   53   27   8.1   4.4   31.5  88.8    10.0      M    M
 28000  -38.1 -36.6   280   50   26   8.1   4.4   31.0  87.7     9.7      M    M
 27000  -35.7 -32.3   285   47   24   7.7   4.2   30.3  86.6     9.3      M    M
 26000  -33.4 -28.1   285   44   22   7.7   4.2   29.5  85.0     8.8      M    M
 25000  -31.1 -24.0   285   40   21   7.7   4.2   28.7  83.7     8.3      M    M
 24000  -28.8 -19.8   285   38   19   8.1   4.4   28.1  82.5     7.8      M    M
 23000  -26.4 -15.5   285   35   18   8.1   4.4   27.4  81.3     7.4      M    M
 22000  -23.9 -11.0   285   33   17   8.1   4.4   26.8  80.2     7.0      M    M
 21000  -21.5  -6.7   285   31   16   8.0   4.4   26.2  79.2     6.6      M    M
 20000  -19.1  -2.4   285   29   15   8.0   4.4   25.6  78.0     6.1      M    M
 19500  -17.9  -0.2   285   28   14   8.0   4.4   25.3  77.5     5.9      M    M
 19000  -16.7   1.9   285   27   14   8.0   4.4   25.0  77.0     5.7      M    M
 18500  -15.5   4.1   285   25   13   7.8   4.3   24.7  76.5     5.5      M    M
 18000  -14.3   6.3   280   24   12   7.8   4.3   24.4  75.8     5.2      M    M
 17500  -12.6   9.3   280   23   12   8.1   4.4   23.9  75.0     4.8      M    M
 17000  -11.4  11.5   280   21   11   8.0   4.4   23.6  74.5     4.6      M    M
 16500  -10.1  13.8   280   20   10   8.6   4.7   23.3  74.0     4.4      M    M
 16000   -8.8  16.2   280   19   10   8.8   4.8   23.2  73.7     4.2      M    M
 15500   -7.5  18.5   280   17    9   8.9   4.9   23.0  73.4     4.1      M    M
 15000   -6.1  21.0   280   17    9   9.1   5.0   22.9  73.2     4.0      M    M
 14500   -4.8  23.4   280   16    8   9.1   5.0   22.8  73.0     3.9      M    M
 14000   -3.4  25.9   285   16    8   8.9   4.9   22.6  72.7     3.8      M    M
 13500   -2.1  28.2   290   16    8   9.0   4.9   22.5  72.5     3.7      M    M
 13000   -0.8  30.6   295   18    9   8.5   4.7   22.3  72.2     3.6      M    M
 12500    0.5  32.9   295   20   10   8.7   4.8   22.2  71.9     3.5      M    M
 12000    1.7  35.1   295   21   11   7.9   4.3   21.9  71.4     3.2      M    M
 11500    2.9  37.2   295   22   12   7.9   4.4   21.6  70.9     3.0      M    M
 11000    4.1  39.4   295   24   12   7.7   4.2   21.3  70.3     2.7      M    M
 10500    5.2  41.4   295   26   14   8.8   4.8   21.0  69.8     2.4      M    M
 10250    5.8  42.4   295   28   14   3.6   2.0   20.8  69.5     2.2      M    M
 10000    5.9  42.6   295   28   14   3.8   2.1   20.2  68.3     1.6      M    M
  9750    6.5  43.7   295   28   14   8.9   4.9   20.0  68.0     1.4      M    M
  9500    7.0  44.6   295   28   14   8.0   4.4   19.9  67.8     1.3      M    M
  9250    7.6  45.7   290   28   15   6.0   3.3   19.7  67.5     1.1      M    M
  9000    7.9  46.2   290   27   14   4.4   2.4   19.3  66.7     0.7      M    M
  8750    8.3  46.9   290   26   13   6.0   3.3   19.0  66.1     0.3      M    M
  8500    8.7  47.7   290   25   13   5.6   3.1   18.7  65.6     0.0      M    M
  8250    9.0  48.2   290   23   12   4.0   2.2   18.3  64.9    -0.4    201  1.0
  8000    9.3  48.7   290   21   11   2.8   1.6   17.8  64.0    -0.9    187  0.9
  7750    9.4  48.9   285   20   10   2.9   1.6   17.2  63.0    -1.4    174  0.9
  7500    9.6  49.3   285   18    9   1.4   0.8   16.7  62.0    -2.0    162  0.8
  7250    9.6  49.3   285   15    8  -0.1  -0.1   16.0  60.7    -2.8    154  0.8
  7000    9.6  49.3   285   13    7  -0.2  -0.1   15.2  59.3    -3.5    148  0.8
  6750    9.5  49.1   285   10    5  -0.1  -0.1   14.4  58.0    -4.3    142  0.7
  6500    9.3  48.7   280    8    4  -8.4  -4.6   13.5  56.2    -5.3    142  0.7
  6250    8.2  46.8   265    7    4 -15.3  -8.4   11.7  53.1    -7.1    165  0.8
  6000    7.2  45.0   250    6    3 -11.1  -6.1    9.9  49.9    -8.9    189  1.0
  5750    6.2  43.2   230    6    3 -21.0 -11.5    8.2  46.8   -10.7    213  1.1
  5500    3.4  38.1   210    4    2 -54.8 -30.1    4.7  40.5   -14.2    289  1.5

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

           02/13/2016 at 0800 MST          |       02/13/2016 at 1100 MST
                                           |
K index... -22.0  LI... +2.7               | K index... -28.7  LI... +4.4
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 -58.6 -73.5  285  54 28   0.1   0.1 | -57.5 -71.5  280  57 29  -0.0  -0.0
 45000 -58.5 -73.3  280  83 43  -1.8  -1.0 | -57.6 -71.7  275  85 44  -1.5  -0.8
 40000 -64.2 -83.6  280  76 39  -3.9  -2.1 | -64.0 -83.2  275  82 42  -4.3  -2.4
 38000 -62.9 -81.2  280  73 38   7.3   4.0 | -63.1 -81.6  270  79 40   7.0   3.8
 36000 -58.5 -73.3  275  70 36   7.3   4.0 | -58.9 -74.0  270  73 38   7.0   3.9
 34000 -53.3 -63.9  275  66 34   8.2   4.5 | -53.8 -64.8  270  67 34   8.5   4.7
 32000 -48.4 -55.1  275  59 30   8.2   4.5 | -48.7 -55.7  270  61 31   8.5   4.7
 30000 -43.5 -46.3  275  51 26   8.2   4.5 | -43.7 -46.7  270  56 29   8.2   4.5
 29000 -41.1 -42.0  275  47 24   8.2   4.5 | -41.2 -42.2  270  55 28   8.2   4.5
 28000 -38.6 -37.5  275  44 22   8.2   4.5 | -38.7 -37.7  270  54 28   8.2   4.5
 27000 -36.2 -33.2  275  41 21   8.0   4.4 | -36.3 -33.3  270  52 27   8.1   4.4
 26000 -33.8 -28.8  275  40 21   8.0   4.4 | -33.9 -29.0  270  48 25   8.1   4.4
 25000 -31.4 -24.5  275  39 20   8.0   4.4 | -31.4 -24.5  270  44 23   8.1   4.4
 24000 -29.0 -20.2  280  38 20   7.8   4.3 | -29.0 -20.2  275  40 21   8.2   4.5
 23000 -26.6 -15.9  280  35 18   7.8   4.3 | -26.5 -15.7  275  38 19   8.2   4.5
 22000 -24.3 -11.7  280  33 17   7.8   4.3 | -24.0 -11.2  275  35 18   8.2   4.5
 21000 -21.9  -7.4  280  30 15   8.1   4.5 | -21.6  -6.9  275  33 17   8.4   4.6
 20000 -19.5  -3.1  280  27 14   8.1   4.4 | -19.0  -2.2  280  31 16   8.4   4.6
 19500 -18.3  -0.9  280  26 13   8.1   4.4 | -17.8  -0.0  280  30 15   8.4   4.6
 19000 -17.0   1.4  280  24 13   8.1   4.5 | -16.5   2.3  280  29 15   8.4   4.6
 18500 -15.8   3.6  280  23 12   7.9   4.3 | -15.3   4.5  280  28 15   7.9   4.3
 18000 -14.7   5.5  275  22 11   7.9   4.4 | -14.1   6.6  280  27 14   7.9   4.3
 17500 -12.8   9.0  275  20 10   8.8   4.8 | -12.3   9.9  285  27 14   8.5   4.7
 17000 -11.5  11.3  280  19 10   8.7   4.8 | -11.0  12.2  285  28 14   8.5   4.7
 16500 -10.2  13.6  280  18  9   8.6   4.7 |  -9.8  14.4  285  29 15   8.0   4.4
 16000  -8.9  16.0  280  18  9   8.5   4.7 |  -8.6  16.5  285  30 15   7.5   4.1
 15500  -7.7  18.1  285  17  9   8.6   4.7 |  -7.5  18.5  285  30 15   7.5   4.1
 15000  -6.3  20.7  285  17  9   8.9   4.9 |  -6.4  20.5  290  31 16   7.9   4.3
 14500  -5.0  23.0  290  17  9   8.9   4.9 |  -5.2  22.6  290  32 17   8.0   4.4
 14000  -3.7  25.3  290  19 10   8.7   4.8 |  -4.1  24.6  290  34 17   6.9   3.8
 13500  -2.4  27.7  295  21 11   8.7   4.8 |  -3.0  26.6  290  34 18   7.0   3.9
 13000  -1.1  30.0  295  23 12   8.6   4.7 |  -1.9  28.6  290  35 18   7.1   3.9
 12500   0.2  32.4  295  26 13   8.7   4.7 |  -0.9  30.4  290  36 19   7.1   3.9
 12000   1.4  34.5  295  28 15   7.5   4.1 |   0.2  32.4  290  37 19   7.1   3.9
 11500   2.5  36.5  295  29 15   7.5   4.1 |   1.2  34.2  295  37 19   7.2   3.9
 11000   3.6  38.5  295  30 15   7.1   3.9 |   2.3  36.1  295  37 19   6.8   3.7
 10500   4.6  40.3  290  31 16   7.7   4.2 |   3.3  37.9  295  36 19   7.3   4.0
 10250   5.2  41.4  290  31 16   4.6   2.5 |   3.8  38.8  295  36 18   4.1   2.3
 10000   5.4  41.7  290  31 16   4.9   2.7 |   4.0  39.2  295  35 18   4.6   2.5
  9750   5.9  42.6  290  30 16   8.1   4.4 |   4.5  40.1  295  34 18   8.0   4.4
  9500   6.5  43.7  290  29 15   7.8   4.3 |   5.0  41.0  295  33 17   7.5   4.1
  9250   7.0  44.6  290  28 14   6.0   3.3 |   5.6  42.1  295  32 16   6.2   3.4
  9000   7.4  45.3  290  27 14   4.1   2.3 |   5.9  42.6  295  30 16   4.7   2.6
  8750   7.7  45.9  290  26 13   5.0   2.7 |   6.3  43.3  290  29 15   5.5   3.0
  8500   8.0  46.4  290  25 13   5.0   2.7 |   6.7  44.1  290  27 14   5.7   3.1
  8250   8.4  47.1  285  23 12   4.2   2.3 |   7.1  44.8  290  25 13   5.1   2.8
  8000   8.6  47.5  285  21 11   3.4   1.9 |   7.4  45.3  285  22 12   4.6   2.5
  7750   8.8  47.8  285  19 10   2.7   1.5 |   7.7  45.9  285  20 10   4.5   2.5
  7500   9.0  48.2  280  17  9   1.7   0.9 |   8.0  46.4  280  18  9   4.6   2.5
  7250   9.0  48.2  280  15  8   1.0   0.5 |   8.4  47.1  280  15  8   5.3   2.9
  7000   9.1  48.4  280  12  6   0.5   0.3 |   8.8  47.8  275  12  6   5.3   2.9
  6750   9.1  48.4  275  10  5   1.2   0.7 |   9.1  48.4  265  10  5   5.3   2.9
  6500   9.0  48.2  270   8  4  -5.5  -3.0 |   9.4  48.9  260   8  4   0.3   0.1
  6250   8.2  46.8  255   7  4 -11.8  -6.4 |   9.1  48.4  245   7  3  -3.9  -2.1
  6000   7.4  45.3  245   7  3  -8.1  -4.4 |   8.9  48.0  235   6  3  -1.7  -0.9
  5750   6.6  43.9  230   7  3 -16.4  -9.0 |   8.6  47.5  220   6  3  -5.0  -2.8
  5500   4.3  39.7  220   6  3 -47.1 -25.8 |   7.7  45.9  215   5  3 -18.0  -9.9

           02/13/2016 at 1400 MST          |       02/13/2016 at 1700 MST
                                           |
K index... -11.7  LI... +6.3               | K index... -17.4  LI... +4.8
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... -0.2
                                           |
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 -57.7 -71.9  280  67 35  -2.1  -1.1 | -57.7 -71.9  285  72 37  -2.4  -1.3
 45000 -60.8 -77.4  275  87 45  -2.0  -1.1 | -61.2 -78.2  275  85 44  -2.4  -1.3
 40000 -64.4 -83.9  275  80 41  -2.3  -1.3 | -62.9 -81.2  275  81 42  -1.0  -0.6
 38000 -62.9 -81.2  270  76 39   6.8   3.7 | -61.8 -79.2  270  81 42   5.4   3.0
 36000 -58.8 -73.8  270  72 37   6.8   3.7 | -58.5 -73.3  270  83 43   5.4   3.0
 34000 -54.5 -66.1  270  66 34   8.7   4.8 | -54.4 -65.9  275  84 43   8.4   4.6
 32000 -49.2 -56.6  270  58 30   8.7   4.8 | -49.3 -56.7  275  80 41   8.5   4.6
 30000 -44.0 -47.2  265  51 26   8.9   4.9 | -44.3 -47.7  275  76 39   8.3   4.6
 29000 -40.7 -41.3  265  47 24   8.9   4.9 | -41.8 -43.2  275  73 38   8.3   4.6
 28000 -38.0 -36.4  265  45 23   8.9   4.9 | -39.3 -38.7  270  70 36   8.3   4.6
 27000 -35.3 -31.5  265  42 22   9.2   5.1 | -36.8 -34.2  270  67 35   8.0   4.4
 26000 -32.6 -26.7  265  40 21   9.2   5.0 | -34.5 -30.1  270  63 32   7.9   4.3
 25000 -29.8 -21.6  270  38 19   9.2   5.0 | -32.1 -25.8  270  59 30   7.9   4.3
 24000 -27.1 -16.8  275  36 18   8.1   4.4 | -29.8 -21.6  265  55 28   8.4   4.6
 23000 -24.8 -12.6  275  36 18   7.7   4.2 | -27.1 -16.8  265  51 26   9.1   5.0
 22000 -22.5  -8.5  280  35 18   7.7   4.2 | -24.3 -11.7  265  48 25   9.2   5.0
 21000 -20.3  -4.5  285  36 18   7.4   4.0 | -21.7  -7.1  265  45 23   6.8   3.7
 20000 -18.0  -0.4  285  37 19   7.4   4.1 | -19.8  -3.6  275  43 22   6.2   3.4
 19500 -16.9   1.6  290  38 20   7.4   4.1 | -18.9  -2.0  280  42 22   6.2   3.4
 19000 -15.8   3.6  290  39 20   7.4   4.1 | -17.9  -0.2  285  42 22   6.2   3.4
 18500 -14.7   5.5  290  40 21   6.7   3.7 | -17.0   1.4  295  43 22   6.3   3.4
 18000 -13.8   7.2  290  41 21   6.5   3.6 | -16.0   3.2  300  43 22   6.3   3.5
 17500 -12.8   9.0  290  42 22   6.5   3.6 | -15.1   4.8  300  43 22   6.3   3.5
 17000 -11.8  10.8  290  42 22   6.5   3.6 | -13.6   7.5  310  45 23   6.9   3.8
 16500 -10.9  12.4  295  43 22   6.5   3.6 | -12.5   9.5  310  47 24   7.0   3.9
 16000  -9.9  14.2  295  43 22   6.2   3.4 | -11.4  11.5  315  49 25   7.6   4.2
 15500  -8.5  16.7  295  43 22   6.2   3.4 | -10.3  13.5  320  50 26   7.5   4.1
 15000  -7.6  18.3  295  43 22   5.9   3.3 |  -9.0  15.8  320  51 26   8.6   4.7
 14500  -6.7  19.9  295  43 22   6.0   3.3 |  -7.8  18.0  320  53 27   8.5   4.7
 14000  -5.9  21.4  295  43 22   5.9   3.3 |  -6.5  20.3  320  54 28   8.3   4.6
 13500  -5.0  23.0  295  42 22   5.9   3.3 |  -5.3  22.5  320  54 28   8.3   4.5
 13000  -4.1  24.6  295  42 22   5.9   3.2 |  -4.0  24.8  320  54 28   7.7   4.2
 12500  -3.2  26.2  295  41 21   5.9   3.2 |  -2.9  26.8  315  53 27   7.5   4.1
 12000  -2.4  27.7  295  40 20   6.0   3.3 |  -1.8  28.8  315  52 27   7.1   3.9
 11500  -1.5  29.3  295  38 20   6.0   3.3 |  -0.8  30.6  315  51 26   6.8   3.7
 11000  -0.6  30.9  295  36 19   6.3   3.4 |   0.1  32.2  310  50 26   6.1   3.3
 10500   0.3  32.5  295  33 17   7.0   3.9 |   0.9  33.6  305  47 24   6.1   3.3
 10250   0.8  33.4  295  32 16   3.6   2.0 |   1.3  34.3  305  46 24   3.6   2.0
 10000   0.9  33.6  295  31 16   4.9   2.7 |   1.5  34.7  305  45 23   3.7   2.0
  9750   1.5  34.7  295  29 15   9.1   5.0 |   1.9  35.4  300  43 22   6.2   3.4
  9500   2.1  35.8  290  28 14   8.2   4.5 |   2.3  36.1  300  41 21   5.6   3.1
  9250   2.7  36.9  290  26 13   7.6   4.2 |   2.7  36.9  300  39 20   5.8   3.2
  9000   3.2  37.8  290  24 12   7.2   4.0 |   3.1  37.6  295  37 19   5.6   3.1
  8750   3.8  38.8  290  22 11   8.2   4.5 |   3.5  38.3  295  35 18   5.6   3.1
  8500   4.4  39.9  285  20 10   8.3   4.5 |   3.9  39.0  290  33 17   5.4   3.0
  8250   5.0  41.0  285  18  9   8.3   4.6 |   4.2  39.6  290  30 16   6.3   3.5
  8000   5.7  42.3  285  16  8   8.5   4.7 |   4.8  40.6  285  27 14   7.3   4.0
  7750   6.3  43.3  280  14  7   8.7   4.8 |   5.3  41.5  280  25 13   6.7   3.7
  7500   7.0  44.6  280  12  6   8.9   4.9 |   5.7  42.3  280  23 12   6.5   3.6
  7250   7.6  45.7  275  11  5   9.6   5.3 |   6.3  43.3  275  21 11   8.0   4.4
  7000   8.4  47.1  270   9  5   9.9   5.4 |   6.9  44.4  270  19 10   9.0   4.9
  6750   9.1  48.4  265   8  4   9.8   5.4 |   7.5  45.5  265  17  9   8.6   4.7
  6500   9.8  49.6  260   6  3   8.3   4.6 |   8.2  46.8  255  16  8   8.5   4.7
  6250  10.3  50.5  255   6  3   6.7   3.7 |   8.8  47.8  255  15  8   8.2   4.5
  6000  10.7  51.3  250   5  2   7.6   4.1 |   9.4  48.9  250  14  7   8.6   4.7
  5750  11.2  52.2  240   4  2   5.3   2.9 |  10.0  50.0  245  14  7   7.5   4.1
  5500  11.3  52.3  225   3  2  -2.2  -1.2 |  10.3  50.5  240  12  6   0.7   0.4
________________________________________________________________________________

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 old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 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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