Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 141315
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0615 MST Tuesday, November 14, 2017

This forecast is for Tuesday, November 14, 2017:

If the trigger temperature of 68.6 F/20.4 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 133 ft/min (0.7 m/s)
   Maximum height of thermals.................. 7853 ft MSL (2546 ft AGL)

Forecast maximum temperature................... 67.0 F/19.9 C
Time of trigger temperature.................... None
Time of overdevelopment........................ 1100 MST
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 6236 ft MSL (929 ft AGL)
Thermal soaring outlook for Wednesday 11/15.... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Slight increase
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 45852 ft MSL (40545 ft AGL)
Wave soaring outlook for Wednesday 11/15....... Poor

Remarks...

Sunrise/Sunset.................... 06:43:25 / 16:44:24 MST
Total possible sunshine........... 10 hr 0 min 59 sec (600 min 59 sec)
Altitude of sun at 11:44:07 MST... 31.86 degrees

Upper air data from numerical model forecast valid on 11/14/2017 at 0500 MST

Freezing level.................. 13188 ft MSL (7881 ft AGL)
Convective condensation level... 20786 ft MSL (15479 ft AGL)
Lifted condensation level....... 16739 ft MSL (11432 ft AGL)
Lifted index.................... +6.8
K index......................... +1.3

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  -66.8 -88.2   280   92   47   1.9   1.0      M     M       M      M    M
 45000  -63.9 -83.0   280  103   53   2.4   1.3      M     M       M      M    M
 40000  -60.1 -76.2   280   94   48   2.0   1.1      M     M       M      M    M
 38000  -56.4 -69.5   275   87   45   6.9   3.8      M     M       M      M    M
 36000  -52.2 -62.0   275   80   41   6.9   3.8      M     M       M      M    M
 34000  -47.9 -54.2   275   73   38   7.7   4.2      M     M       M      M    M
 32000  -43.3 -45.9   275   68   35   7.7   4.2      M     M       M      M    M
 30000  -38.1 -36.6   275   61   31   7.7   4.2   37.2  98.9    13.4      M    M
 29000  -35.8 -32.4   275   58   30   7.7   4.2   36.3  97.4    12.9      M    M
 28000  -33.5 -28.3   275   55   28   7.7   4.2   35.7  96.2    12.5      M    M
 27000  -31.2 -24.2   280   53   27   7.8   4.3   34.9  94.8    12.1      M    M
 26000  -28.9 -20.0   280   52   27   7.8   4.3   34.1  93.3    11.6      M    M
 25000  -26.6 -15.9   280   50   26   7.8   4.3   33.4  92.1    11.1      M    M
 24000  -24.2 -11.6   280   49   25   8.1   4.5   32.7  90.9    10.7      M    M
 23000  -21.8  -7.2   280   47   24   8.1   4.4   32.1  89.7    10.3      M    M
 22000  -19.4  -2.9   275   46   24   8.1   4.4   31.5  88.7    10.0      M    M
 21000  -17.0   1.4   275   44   23   7.9   4.3   30.9  87.6     9.5      M    M
 20000  -14.6   5.7   275   41   21   7.9   4.3   30.2  86.4     9.1      M    M
 19500  -13.5   7.7   275   39   20   7.9   4.3   29.9  85.8     8.9      M    M
 19000  -12.3   9.9   275   38   20   7.8   4.3   29.6  85.3     8.7      M    M
 18500  -11.2  11.8   275   36   19   6.7   3.7   29.2  84.5     8.3      M    M
 18000  -10.2  13.6   275   34   18   6.8   3.7   28.7  83.6     7.9      M    M
 17500   -9.2  15.4   275   32   17   6.7   3.7   28.2  82.7     7.5      M    M
 17000   -8.2  17.2   275   31   16   6.7   3.7   27.6  81.7     7.1      M    M
 16500   -7.2  19.0   275   29   15   6.8   3.7   27.1  80.8     6.6      M    M
 16000   -6.2  20.8   275   28   14   7.0   3.8   26.6  80.0     6.2      M    M
 15500   -4.6  23.7   280   26   13   7.0   3.8   26.0  78.7     5.7      M    M
 15000   -3.6  25.5   280   25   13   6.9   3.8   25.5  77.9     5.2      M    M
 14500   -2.6  27.3   280   24   13   7.0   3.8   25.0  77.0     4.8      M    M
 14000   -1.5  29.3   280   23   12   7.2   3.9   24.6  76.2     4.4      M    M
 13500   -0.5  31.1   280   22   11   7.2   3.9   24.2  75.5     4.1      M    M
 13000    0.5  32.9   280   20   10   6.8   3.7   23.7  74.6     3.7      M    M
 12500    1.5  34.7   280   19   10   6.8   3.7   23.2  73.8     3.2      M    M
 12000    2.5  36.5   275   17    9   6.7   3.7   22.7  72.9     2.8      M    M
 11500    3.5  38.3   275   16    8   6.6   3.6   22.2  72.0     2.3      M    M
 11000    4.6  40.3   270   14    7   7.9   4.3   21.8  71.3     1.9      M    M
 10500    5.7  42.3   265   12    6   8.6   4.7   21.5  70.7     1.6      M    M
 10250    6.3  43.3   260   11    6   4.9   2.7   21.4  70.5     1.5      M    M
 10000    6.6  43.9   260   11    6   5.8   3.2   20.9  69.6     1.0      M    M
  9750    7.2  45.0   265   11    6   9.9   5.4   20.8  69.5     0.9      M    M
  9500    7.9  46.2   265   11    5   9.3   5.1   20.8  69.4     0.9      M    M
  9250    8.6  47.5   265   10    5   7.5   4.1   20.8  69.4     0.9      M    M
  9000    9.1  48.4   265   10    5   6.7   3.7   20.5  68.9     0.6      M    M
  8750    9.7  49.5   265   10    5   8.3   4.6   20.3  68.6     0.5      M    M
  8500   10.3  50.5   265   10    5   7.9   4.3   20.2  68.4     0.3      M    M
  8250   10.9  51.6   265   10    5   8.3   4.5   20.1  68.1     0.2      M    M
  8000   11.5  52.7   265   10    5   8.1   4.4   20.0  67.9     0.1      M    M
  7750   12.1  53.8   260    9    5   7.4   4.0   19.8  67.7    -0.1    124  0.6
  7500   12.6  54.7   260    9    5   7.4   4.0   19.6  67.3    -0.2    100  0.5
  7250   13.2  55.8   255    8    4   8.2   4.5   19.5  67.0    -0.4     75  0.4
  7000   13.8  56.8   255    8    4   7.5   4.1   19.3  66.8    -0.5     50  0.3
  6750   14.4  57.9   255    7    4  10.1   5.5   19.2  66.6    -0.7     25  0.1
  6500   14.9  58.8   250    7    4  -3.2  -1.8   19.0  66.2    -0.9      2  0.0
  6250   13.9  57.0   245    7    4 -16.8  -9.2   17.2  63.0    -2.6     24  0.1
  6000   12.9  55.2   245    7    4 -10.2  -5.6   15.5  59.9    -4.4     47  0.2
  5750   12.0  53.6   240    8    4 -19.5 -10.7   13.8  56.9    -6.0     68  0.3
  5500    9.2  48.6   235    8    4 -58.5 -32.1   10.3  50.6    -9.5    144  0.7

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

           11/14/2017 at 0800 MST          |       11/14/2017 at 1100 MST
                                           |
K index... -3.4  LI... +5.6                | K index... -7.9  LI... +6.2
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -66.6 -87.9  280  95 49   1.8   1.0 | -65.8 -86.4  275  98 51   1.8   1.0
 45000 -63.8 -82.8  280 110 56   1.9   1.1 | -63.3 -81.9  275 112 58   0.9   0.5
 40000 -60.8 -77.4  275 100 51   1.7   0.9 | -61.8 -79.2  270  96 50   0.8   0.4
 38000 -57.2 -71.0  275  91 47   6.9   3.8 | -58.2 -72.8  270  88 45   7.4   4.1
 36000 -53.0 -63.4  275  82 42   6.9   3.8 | -53.7 -64.7  270  78 40   7.4   4.1
 34000 -48.6 -55.5  275  74 38   8.2   4.5 | -49.0 -56.2  265  72 37   8.5   4.7
 32000 -43.7 -46.7  275  68 35   8.2   4.5 | -43.9 -47.0  265  70 36   8.5   4.7
 30000 -39.1 -38.4  275  63 33   6.9   3.8 | -39.1 -38.4  265  67 34   7.4   4.1
 29000 -36.5 -33.7  270  61 31   7.0   3.8 | -36.9 -34.4  265  65 33   7.4   4.1
 28000 -34.4 -29.9  270  59 30   7.0   3.8 | -34.1 -29.4  265  62 32   7.4   4.1
 27000 -32.1 -25.8  270  58 30   8.2   4.5 | -31.8 -25.2  265  61 31   8.0   4.4
 26000 -29.7 -21.5  270  57 30   8.3   4.5 | -29.4 -20.9  265  60 31   8.0   4.4
 25000 -27.2 -17.0  270  57 29   8.3   4.5 | -27.1 -16.8  265  59 30   8.0   4.4
 24000 -24.8 -12.6  270  55 29   8.0   4.4 | -24.7 -12.5  265  58 30   8.1   4.4
 23000 -22.4  -8.3  270  52 27   8.0   4.4 | -22.2  -8.0  265  56 29   8.1   4.4
 22000 -20.0  -4.0  270  49 25   8.0   4.4 | -19.8  -3.6  265  55 28   8.1   4.4
 21000 -17.6   0.3  265  46 23   8.2   4.5 | -17.3   0.9  265  53 27   8.6   4.7
 20000 -15.1   4.8  265  43 22   8.2   4.5 | -14.7   5.5  265  50 26   8.6   4.7
 19500 -13.9   7.0  265  42 22   8.2   4.5 | -13.4   7.9  265  49 25   8.6   4.7
 19000 -12.6   9.3  265  41 21   8.2   4.5 | -12.2  10.0  265  48 24   8.7   4.7
 18500 -11.5  11.3  265  40 20   7.4   4.1 | -10.9  12.4  265  46 24   7.6   4.2
 18000 -10.4  13.3  265  39 20   7.5   4.1 |  -9.8  14.4  265  44 23   7.7   4.2
 17500  -9.2  15.4  265  38 20   7.3   4.0 |  -8.6  16.5  265  43 22   7.2   4.0
 17000  -8.2  17.2  270  37 19   7.3   4.0 |  -7.6  18.3  265  41 21   6.9   3.8
 16500  -7.1  19.2  270  35 18   7.4   4.0 |  -6.6  20.1  265  39 20   6.8   3.8
 16000  -5.9  21.4  270  34 18   7.8   4.3 |  -5.7  21.7  265  37 19   5.8   3.2
 15500  -4.8  23.4  270  34 17   7.9   4.3 |  -4.8  23.4  265  34 18   5.8   3.2
 15000  -3.2  26.2  270  31 16   6.7   3.7 |  -3.5  25.7  265  30 16   6.1   3.3
 14500  -2.2  28.0  270  29 15   6.7   3.7 |  -2.6  27.3  265  28 14   6.1   3.3
 14000  -1.2  29.8  270  27 14   7.2   3.9 |  -1.6  29.1  265  25 13   7.0   3.8
 13500  -0.1  31.8  275  25 13   7.2   4.0 |  -0.6  30.9  265  23 12   7.0   3.8
 13000   0.9  33.6  275  23 12   6.4   3.5 |   0.4  32.7  260  21 11   6.2   3.4
 12500   1.8  35.2  275  20 10   6.4   3.5 |   1.3  34.3  260  18  9   6.1   3.4
 12000   2.8  37.0  280  18  9   7.1   3.9 |   2.3  36.1  260  17  9   7.7   4.2
 11500   3.8  38.8  280  16  8   7.1   3.9 |   3.5  38.3  260  17  9   8.0   4.4
 11000   4.9  40.8  280  14  7   7.1   3.9 |   4.5  40.1  265  17  9   5.8   3.2
 10500   5.9  42.6  280  12  6   8.0   4.4 |   5.3  41.5  265  16  8   4.5   2.5
 10250   6.5  43.7  280  11  5   3.6   2.0 |   5.7  42.3  260  15  8   8.9   4.9
 10000   6.6  43.9  275  10  5   4.2   2.3 |   6.5  43.7  265  16  8   9.1   5.0
  9750   7.2  45.0  275   9  5   8.8   4.8 |   6.9  44.4  265  16  8   4.9   2.7
  9500   7.7  45.9  275   9  4   8.2   4.5 |   7.3  45.1  265  15  8   6.1   3.4
  9250   8.3  46.9  275   8  4   6.0   3.3 |   7.8  46.0  270  14  7   5.4   3.0
  9000   8.7  47.7  275   8  4   5.7   3.1 |   8.1  46.6  265  13  7   6.0   3.3
  8750   9.2  48.6  280   9  4   8.2   4.5 |   8.6  47.5  265  13  7   6.7   3.7
  8500   9.8  49.6  280  10  5   7.8   4.3 |   9.1  48.4  265  13  6   6.6   3.6
  8250  10.4  50.7  280  11  5   6.2   3.4 |   9.6  49.3  265  12  6   6.5   3.5
  8000  10.7  51.3  275  11  5   4.8   2.6 |  10.1  50.2  260  10  5   6.5   3.5
  7750  11.1  52.0  275  11  5   5.5   3.0 |  10.5  50.9  260   9  5   6.8   3.8
  7500  11.5  52.7  275  10  5   5.6   3.0 |  11.1  52.0  255   8  4   7.0   3.9
  7250  11.9  53.4  275  10  5   6.0   3.3 |  11.6  52.9  250   7  3   7.7   4.2
  7000  12.4  54.3  270   9  4   5.4   3.0 |  12.2  54.0  240   6  3   8.0   4.4
  6750  12.9  55.2  265   8  4   8.4   4.6 |  12.8  55.0  225   5  2   8.1   4.4
  6500  13.3  55.9  260   7  3  -0.6  -0.3 |  13.4  56.1  210   4  2   6.4   3.5
  6250  12.7  54.9  250   6  3 -11.7  -6.4 |  13.7  56.7  200   4  2   4.0   2.2
  6000  11.9  53.4  240   7  3  -8.2  -4.5 |  14.0  57.2  195   4  2   4.4   2.4
  5750  11.3  52.3  230   7  4 -12.4  -6.8 |  14.2  57.6  190   4  2  -0.7  -0.4
  5500   9.5  49.1  225   8  4 -38.6 -21.2 |  13.9  57.0  195   4  2  -4.0  -2.2

           11/14/2017 at 1400 MST          |       11/14/2017 at 1700 MST
                                           |
K index... -3.7  LI... +7.1                | K index... +6.6  LI... +6.0
CAPE... 0.0  CIN... 0.0                    | CAPE... 0.0  CIN... 0.0
                                           |
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 -65.0 -85.0  275  96 49   1.3   0.7 | -64.2 -83.6  275  91 47   1.3   0.7
 45000 -63.0 -81.4  275 102 53   0.8   0.4 | -62.3 -80.1  280  98 50   1.1   0.6
 40000 -61.8 -79.2  270  95 49   0.9   0.5 | -60.6 -77.1  275 106 55   1.1   0.6
 38000 -58.7 -73.7  270  90 46   7.0   3.8 | -58.1 -72.6  275 103 53   5.9   3.2
 36000 -54.5 -66.1  270  84 43   7.0   3.8 | -54.6 -66.3  275  96 49   5.9   3.2
 34000 -49.4 -56.9  270  78 40   8.4   4.6 | -50.0 -58.0  280  90 46   8.5   4.6
 32000 -44.3 -47.7  265  73 38   8.4   4.6 | -44.9 -48.8  280  89 46   8.5   4.6
 30000 -39.3 -38.7  265  68 35   8.3   4.5 | -40.1 -40.2  280  84 43   7.5   4.1
 29000 -36.8 -34.2  265  65 34   8.3   4.5 | -37.8 -36.0  275  79 41   7.5   4.1
 28000 -34.4 -29.9  265  62 32   8.3   4.5 | -35.6 -32.1  275  75 38   7.5   4.1
 27000 -31.9 -25.4  265  60 31   7.9   4.3 | -33.3 -27.9  270  71 37   8.4   4.6
 26000 -29.6 -21.3  265  58 30   7.9   4.3 | -30.8 -23.4  270  69 35   8.4   4.6
 25000 -27.2 -17.0  265  57 29   7.9   4.3 | -28.3 -18.9  265  67 34   8.4   4.6
 24000 -24.8 -12.6  270  55 28   7.8   4.3 | -25.8 -14.4  265  65 33   8.4   4.6
 23000 -22.5  -8.5  270  55 28   7.8   4.3 | -23.2  -9.8  265  64 33   8.5   4.6
 22000 -20.2  -4.4  270  55 29   7.8   4.3 | -20.7  -5.3  270  63 32   8.5   4.7
 21000 -17.8  -0.0  270  55 28   8.5   4.7 | -18.3  -0.9  270  62 32   6.4   3.5
 20000 -15.2   4.6  270  55 28   8.5   4.6 | -16.3   2.7  270  58 30   6.6   3.6
 19500 -13.9   7.0  270  54 28   8.5   4.6 | -15.3   4.5  270  57 29   6.6   3.6
 19000 -12.7   9.1  270  54 28   8.5   4.7 | -14.3   6.3  270  55 28   6.6   3.6
 18500 -11.4  11.5  270  53 27   7.6   4.1 | -13.4   7.9  270  54 28   5.9   3.2
 18000  -9.8  14.4  270  51 26   7.6   4.2 | -12.5   9.5  270  52 27   5.8   3.2
 17500  -8.7  16.3  270  50 26   6.4   3.5 | -11.3  11.7  275  49 25   5.5   3.0
 17000  -7.7  18.1  270  48 25   6.3   3.4 | -10.5  13.1  275  47 24   5.5   3.0
 16500  -6.8  19.8  275  46 24   5.9   3.2 |  -9.7  14.5  275  45 23   5.6   3.1
 16000  -6.0  21.2  275  44 23   5.2   2.9 |  -8.9  16.0  275  43 22   5.8   3.2
 15500  -5.2  22.6  275  41 21   5.2   2.9 |  -8.0  17.6  275  41 21   5.8   3.2
 15000  -4.5  23.9  275  39 20   5.2   2.9 |  -7.2  19.0  275  40 20   5.9   3.3
 14500  -3.7  25.3  275  36 19   5.3   2.9 |  -6.3  20.7  275  38 19   5.9   3.2
 14000  -2.9  26.8  275  33 17   4.8   2.7 |  -5.4  22.3  280  36 19   6.7   3.7
 13500  -2.2  28.0  280  30 15   4.8   2.6 |  -4.4  24.1  280  34 18   6.7   3.7
 13000  -1.5  29.3  280  27 14   5.8   3.2 |  -3.4  25.9  280  33 17   6.8   3.7
 12500  -0.6  30.9  280  24 12   6.0   3.3 |  -2.4  27.7  280  31 16   6.8   3.7
 12000   0.3  32.5  280  21 11   6.5   3.6 |  -1.3  29.7  285  30 15   7.4   4.1
 11500   1.3  34.3  275  19 10   6.7   3.7 |  -0.2  31.6  285  29 15   7.6   4.2
 11000   2.3  36.1  275  16  8   6.7   3.7 |   0.9  33.6  285  27 14   8.0   4.4
 10500   3.3  37.9  275  15  8   5.9   3.3 |   2.1  35.8  290  27 14   8.8   4.8
 10250   3.8  38.8  275  14  7   9.7   5.3 |   2.7  36.9  290  27 14   5.0   2.8
 10000   4.6  40.3  275  14  7  10.5   5.8 |   3.0  37.4  290  26 14   6.2   3.4
  9750   5.2  41.4  275  12  6   7.4   4.0 |   3.7  38.7  290  26 13  10.6   5.8
  9500   5.8  42.4  275  11  5   8.1   4.5 |   4.5  40.1  290  26 13   9.9   5.4
  9250   6.4  43.5  275   9  4   8.2   4.5 |   5.2  41.4  290  26 13   8.2   4.5
  9000   7.0  44.6  270   7  3   8.9   4.9 |   5.7  42.3  295  25 13   7.6   4.2
  8750   7.7  45.9  275   6  3   9.1   5.0 |   6.4  43.5  295  24 12   9.5   5.2
  8500   8.4  47.1  275   5  2   9.0   4.9 |   7.1  44.8  300  23 12   9.4   5.1
  8250   9.1  48.4  280   4  2   9.2   5.1 |   7.8  46.0  300  23 12   9.0   4.9
  8000   9.8  49.6  290   3  2   9.4   5.2 |   8.4  47.1  300  22 11   8.5   4.7
  7750  10.5  50.9  295   3  1   9.2   5.1 |   9.1  48.4  305  22 11   8.6   4.7
  7500  11.1  52.0  305   3  1   9.2   5.0 |   9.7  49.5  305  21 11   8.6   4.7
  7250  11.8  53.2  310   3  1   9.9   5.4 |  10.4  50.7  310  20 10   9.3   5.1
  7000  12.6  54.7  315   3  1  10.4   5.7 |  11.1  52.0  315  19 10   9.6   5.2
  6750  13.4  56.1  315   3  1   9.5   5.2 |  11.8  53.2  315  19 10   8.6   4.7
  6500  14.1  57.4  320   3  1   9.5   5.2 |  12.4  54.3  320  18  9   8.2   4.5
  6250  14.8  58.6  320   3  2  10.2   5.6 |  13.0  55.4  320  17  9   8.4   4.6
  6000  15.6  60.1  320   3  2  10.3   5.6 |  13.6  56.5  325  16  8   9.0   5.0
  5750  16.3  61.3  320   3  2  10.1   5.6 |  14.3  57.7  330  15  8   6.7   3.7
  5500  17.1  62.8  325   3  2  11.9   6.6 |  14.4  57.9  330  13  6  -2.9  -1.6
________________________________________________________________________________

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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