Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 160120
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1820 MST Wednesday, November 15, 2017

This forecast is for Thursday, November 16, 2017:

If the trigger temperature of 67.3 F/19.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 791 ft/min (4.0 m/s)
   Maximum height of thermals.................. 14359 ft MSL (9052 ft AGL)

Forecast maximum temperature................... 73.0 F/23.2 C
Time of trigger temperature.................... 1100 MST
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................. 9371 ft MSL (4064 ft AGL)
Thermal soaring outlook for Friday 11/17....... Good

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....................... 45420 ft MSL (40113 ft AGL)
Wave soaring outlook for Friday 11/17.......... Fair

Remarks...

Sunrise/Sunset.................... 06:45:41 / 16:42:52 MST
Total possible sunshine........... 9 hr 57 min 11 sec (597 min 11 sec)
Altitude of sun at 11:44:28 MST... 31.36 degrees

Upper air data from numerical model forecast valid on 11/16/2017 at 0500 MST

Freezing level.................. 12559 ft MSL (7252 ft AGL)
Convective condensation level... 19407 ft MSL (14100 ft AGL)
Lifted condensation level....... 18278 ft MSL (12972 ft AGL)
Lifted index.................... +4.1
K index......................... +8.8

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  -67.3 -89.1   280   96   50   2.3   1.3      M     M       M      M    M
 45000  -63.5 -82.3   285  113   58   4.0   2.2      M     M       M      M    M
 40000  -57.7 -71.9   290  109   56   3.9   2.1      M     M       M      M    M
 38000  -55.1 -67.2   290   97   50   4.4   2.4      M     M       M      M    M
 36000  -52.5 -62.5   285   81   42   4.4   2.4      M     M       M      M    M
 34000  -49.4 -56.9   285   69   35   7.1   3.9      M     M       M      M    M
 32000  -44.6 -48.3   280   64   33   7.1   3.9      M     M       M      M    M
 30000  -39.9 -39.8   280   61   31   8.7   4.8   35.6  96.1     9.7      M    M
 29000  -37.2 -35.0   280   58   30   8.7   4.8   35.2  95.3     9.5      M    M
 28000  -34.6 -30.3   280   56   29   8.7   4.8   34.8  94.7     9.3      M    M
 27000  -32.1 -25.8   275   53   27   8.0   4.4   34.4  94.0     9.1      M    M
 26000  -29.6 -21.3   275   49   25   8.1   4.4   33.7  92.7     8.7      M    M
 25000  -27.2 -17.0   275   45   23   8.1   4.4   33.1  91.6     8.3      M    M
 24000  -24.9 -12.8   275   41   21   6.0   3.3   32.4  90.4     7.8      M    M
 23000  -23.2  -9.8   275   38   19   5.8   3.2   30.9  87.6     6.6      M    M
 22000  -21.5  -6.7   275   35   18   5.8   3.2   29.4  85.0     5.5      M    M
 21000  -19.7  -3.5   275   32   17   6.9   3.8   28.2  82.7     4.4      M    M
 20000  -17.7   0.1   275   32   16   6.8   3.8   27.1  80.8     3.5      M    M
 19500  -16.7   1.9   275   32   16   6.9   3.8   26.6  79.9     3.1      M    M
 19000  -15.7   3.7   275   32   16   6.8   3.7   26.1  79.0     2.7      M    M
 18500  -14.6   5.7   275   31   16   8.3   4.5   25.7  78.3     2.3      M    M
 18000  -13.4   7.9   275   31   16   8.4   4.6   25.5  77.9     2.1      M    M
 17500  -12.1  10.2   275   31   16   8.2   4.5   25.3  77.6     2.0      M    M
 17000  -11.0  12.2   275   30   15   7.4   4.1   24.9  76.9     1.6      M    M
 16500   -9.3  15.3   270   29   15   7.6   4.2   24.4  75.8     1.1      M    M
 16000   -8.2  17.2   270   28   14   7.9   4.3   24.0  75.2     0.8      M    M
 15500   -7.0  19.4   270   27   14   7.9   4.3   23.7  74.7     0.5      M    M
 15000   -5.8  21.6   270   26   13   8.2   4.5   23.4  74.2     0.3      M    M
 14500   -4.6  23.7   265   25   13   8.2   4.5   23.2  73.7     0.0      M    M
 14000   -3.3  26.1   265   24   12   8.0   4.4   22.9  73.2    -0.2    746  3.8
 13500   -2.1  28.2   270   23   12   8.0   4.4   22.6  72.7    -0.5    695  3.5
 13000   -0.9  30.4   270   23   12   8.2   4.5   22.3  72.2    -0.7    644  3.3
 12500    0.3  32.5   265   22   11   8.2   4.5   22.1  71.8    -1.0    592  3.0
 12000    1.5  34.7   265   22   11   7.8   4.3   21.8  71.3    -1.2    541  2.7
 11500    2.6  36.7   265   22   11   7.7   4.2   21.5  70.7    -1.6    492  2.5
 11000    3.8  38.8   270   21   11   7.0   3.9   21.1  70.1    -1.9    443  2.3
 10500    4.8  40.6   270   20   10   6.0   3.3   20.7  69.2    -2.4    398  2.0
 10250    5.3  41.5   270   19   10   9.7   5.3   20.4  68.8    -2.6    375  1.9
 10000    6.2  43.2   270   19   10   9.9   5.4   20.6  69.0    -2.4    342  1.7
  9750    6.7  44.1   270   18    9   6.0   3.3   20.4  68.6    -2.7    319  1.6
  9500    7.2  45.0   270   17    9   7.7   4.2   20.1  68.2    -2.9    296  1.5
  9250    7.7  45.9   270   16    8   4.9   2.7   19.9  67.8    -3.1    273  1.4
  9000    8.0  46.4   270   15    8   4.2   2.3   19.4  67.0    -3.6    258  1.3
  8750    8.4  47.1   270   17    9   6.5   3.6   19.1  66.4    -3.9    238  1.2
  8500    8.9  48.0   275   19   10   6.9   3.8   18.9  66.0    -4.2    216  1.1
  8250    9.4  48.9   275   21   11   4.9   2.7   18.6  65.5    -4.4    194  1.0
  8000    9.6  49.3   270   20   10   2.0   1.1   18.1  64.6    -4.9    180  0.9
  7750    9.7  49.5   270   18    9   2.4   1.3   17.5  63.5    -5.5    168  0.9
  7500    9.9  49.8   270   16    8   2.5   1.4   17.0  62.5    -6.1    155  0.8
  7250   10.1  50.2   265   14    7   4.1   2.3   16.4  61.6    -6.6    141  0.7
  7000   10.5  50.9   260   11    6   5.3   2.9   16.1  60.9    -7.0    123  0.6
  6750   10.9  51.6   250    9    5   5.8   3.2   15.7  60.3    -7.4    104  0.5
  6500   11.3  52.3   240    7    4   1.4   0.7   15.3  59.6    -7.7     86  0.4
  6250   11.0  51.8   225    7    4  -8.2  -4.5   14.3  57.8    -8.8     87  0.4
  6000   10.2  50.4   220    8    4  -9.7  -5.3   12.8  55.1   -10.3    102  0.5
  5750    9.5  49.1   210    9    5 -13.0  -7.1   11.3  52.4   -11.8    118  0.6
  5500    7.5  45.5   215   12    6 -44.6 -24.5    8.7  47.7   -14.5    168  0.9

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

           11/16/2017 at 0800 MST          |       11/16/2017 at 1100 MST
                                           |
K index... +11.5  LI... +2.0               | K index... +7.3  LI... +4.8
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 -67.3 -89.1  280  97 50   2.4   1.3 | -68.2 -90.8  280 104 53   2.5   1.4
 45000 -63.3 -81.9  280 111 57   3.9   2.1 | -64.1 -83.4  275 111 57   3.8   2.1
 40000 -57.6 -71.7  290 117 60   3.8   2.1 | -58.5 -73.3  285 119 61   3.8   2.1
 38000 -55.3 -67.5  290 102 53   3.8   2.1 | -55.6 -68.1  285 108 56   5.2   2.9
 36000 -53.0 -63.4  285  79 41   3.8   2.1 | -52.5 -62.5  290  93 48   5.2   2.9
 34000 -49.8 -57.6  285  63 32   8.2   4.5 | -48.8 -55.8  290  79 41   7.9   4.3
 32000 -44.3 -47.7  280  59 30   8.2   4.5 | -43.5 -46.3  285  67 34   7.9   4.3
 30000 -39.4 -38.9  280  55 29   8.1   4.4 | -38.5 -37.3  280  60 31   8.6   4.7
 29000 -37.0 -34.6  280  53 27   8.1   4.4 | -36.0 -32.8  280  59 31   8.6   4.7
 28000 -34.6 -30.3  280  51 26   8.1   4.4 | -33.4 -28.1  280  58 30   8.6   4.7
 27000 -32.2 -26.0  275  49 25   7.6   4.1 | -30.9 -23.6  280  57 29   8.0   4.4
 26000 -29.9 -21.8  275  46 24   7.6   4.2 | -28.5 -19.3  280  54 28   8.0   4.4
 25000 -27.6 -17.7  275  43 22   7.6   4.2 | -26.1 -15.0  280  51 26   8.0   4.4
 24000 -25.4 -13.7  275  40 21   6.9   3.8 | -23.8 -10.8  275  49 25   7.3   4.0
 23000 -23.4 -10.1  275  39 20   6.8   3.7 | -21.6  -6.9  275  46 24   7.3   4.0
 22000 -21.3  -6.3  275  37 19   6.8   3.7 | -19.4  -2.9  275  44 22   7.3   4.0
 21000 -19.3  -2.7  275  35 18   6.5   3.6 | -17.3   0.9  275  41 21   6.5   3.6
 20000 -17.4   0.7  275  34 17   6.6   3.6 | -15.3   4.5  275  39 20   6.6   3.6
 19500 -16.4   2.5  270  33 17   6.6   3.6 | -14.4   6.1  275  38 20   6.6   3.6
 19000 -15.4   4.3  270  33 17   6.6   3.6 | -13.4   7.9  275  38 19   6.6   3.6
 18500 -14.4   6.1  270  32 16   7.4   4.1 | -12.4   9.7  275  37 19   6.7   3.7
 18000 -13.3   8.1  270  31 16   7.5   4.1 | -11.4  11.5  275  37 19   6.7   3.7
 17500 -12.2  10.0  270  30 16   7.5   4.1 | -10.4  13.3  275  37 19   6.6   3.6
 17000 -11.1  12.0  270  30 15   7.6   4.2 |  -9.5  14.9  275  36 19   6.0   3.3
 16500  -9.4  15.1  265  30 15   8.1   4.4 |  -8.2  17.2  275  35 18   6.3   3.5
 16000  -8.1  17.4  265  30 15   8.7   4.8 |  -7.2  19.0  275  35 18   6.8   3.7
 15500  -6.8  19.8  270  30 15   8.7   4.7 |  -6.2  20.8  275  36 18   6.8   3.7
 15000  -5.6  21.9  270  30 16   8.2   4.5 |  -5.2  22.6  275  36 18   6.9   3.8
 14500  -4.4  24.1  270  31 16   8.2   4.5 |  -4.2  24.4  275  35 18   6.9   3.8
 14000  -3.2  26.2  270  31 16   8.1   4.4 |  -3.1  26.4  275  35 18   7.3   4.0
 13500  -2.0  28.4  270  32 17   8.1   4.5 |  -2.0  28.4  275  35 18   7.4   4.0
 13000  -0.8  30.6  270  33 17   7.6   4.2 |  -1.0  30.2  275  34 18   7.4   4.1
 12500   0.3  32.5  270  33 17   7.6   4.1 |   0.1  32.2  275  32 16   7.4   4.1
 12000   1.4  34.5  270  33 17   7.6   4.2 |   1.2  34.2  275  30 15   7.8   4.3
 11500   2.5  36.5  270  31 16   7.6   4.2 |   2.4  36.3  275  30 15   7.9   4.4
 11000   3.7  38.7  270  29 15   7.4   4.1 |   3.6  38.5  270  29 15   7.1   3.9
 10500   4.8  40.6  270  29 15   6.5   3.5 |   4.6  40.3  270  26 14   6.1   3.4
 10250   5.3  41.5  270  29 15  10.9   6.0 |   5.1  41.2  270  25 13   8.8   4.8
 10000   6.3  43.3  275  30 15  11.5   6.3 |   5.8  42.4  270  25 13   9.4   5.1
  9750   6.9  44.4  275  30 15   7.3   4.0 |   6.4  43.5  270  23 12   7.2   4.0
  9500   7.6  45.7  275  30 15   8.9   4.9 |   7.0  44.6  270  22 11   7.6   4.2
  9250   8.2  46.8  275  30 16   6.8   3.7 |   7.6  45.7  265  20 10   8.2   4.5
  9000   8.6  47.5  275  29 15   5.8   3.2 |   8.2  46.8  265  18  9   8.2   4.5
  8750   9.1  48.4  275  29 15   6.9   3.8 |   8.8  47.8  260  17  9   7.4   4.1
  8500   9.7  49.5  275  29 15   7.0   3.8 |   9.3  48.7  260  15  8   7.4   4.1
  8250  10.2  50.4  275  29 15   6.1   3.4 |   9.9  49.8  255  14  7   8.2   4.5
  8000  10.5  50.9  270  26 13   3.9   2.1 |  10.6  51.1  255  13  7   8.9   4.9
  7750  10.8  51.4  270  23 12   2.1   1.2 |  11.2  52.2  250  13  7   8.1   4.4
  7500  10.9  51.6  270  21 11   1.4   0.8 |  11.8  53.2  245  12  6   7.9   4.3
  7250  11.0  51.8  265  18  9   2.1   1.1 |  12.4  54.3  240  12  6   7.3   4.0
  7000  11.2  52.2  265  15  8   2.2   1.2 |  12.9  55.2  235  11  6   6.3   3.5
  6750  11.4  52.5  255  12  6   3.0   1.6 |  13.4  56.1  225  11  6   5.6   3.1
  6500  11.6  52.9  245  10  5  -0.3  -0.1 |  13.7  56.7  220  11  5   4.1   2.2
  6250  11.2  52.2  235   9  5  -7.8  -4.3 |  13.9  57.0  215  10  5   1.6   0.9
  6000  10.5  50.9  220   9  5  -8.6  -4.7 |  14.0  57.2  210   9  5   1.0   0.6
  5750   9.8  49.6  210  10  5 -12.9  -7.1 |  14.0  57.2  200   9  5  -1.6  -0.9
  5500   8.0  46.4  210  13  7 -38.8 -21.3 |  13.8  56.8  190   7  4  -1.1  -0.6

           11/16/2017 at 1400 MST          |       11/16/2017 at 1700 MST
                                           |
K index... +5.5  LI... +5.8                | K index... +2.9  LI... +4.8
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 -70.1 -94.2  275  98 50   4.0   2.2 | -69.2 -92.6  270  91 47   5.0   2.7
 45000 -64.0 -83.2  275 100 52   4.6   2.5 | -61.8 -79.2  270  96 49   4.4   2.4
 40000 -57.1 -70.8  280 117 60   4.6   2.5 | -54.9 -66.8  280 125 64   4.5   2.5
 38000 -54.3 -65.7  280 113 58   4.7   2.6 | -53.0 -63.4  280 123 63   2.8   1.5
 36000 -51.4 -60.5  285 106 55   4.7   2.6 | -51.4 -60.5  285 118 61   2.8   1.5
 34000 -47.2 -53.0  285  96 50   8.3   4.5 | -48.2 -54.8  285 113 58   8.8   4.8
 32000 -42.2 -44.0  285  86 44   8.3   4.5 | -42.9 -45.2  285 107 55   8.8   4.8
 30000 -37.4 -35.3  285  78 40   7.7   4.2 | -38.1 -36.6  285  98 51   6.9   3.8
 29000 -35.0 -31.0  280  75 38   7.7   4.2 | -36.0 -32.8  285  91 47   7.0   3.8
 28000 -32.7 -26.9  280  72 37   7.7   4.2 | -33.4 -28.1  280  82 42   7.0   3.8
 27000 -30.5 -22.9  280  69 36   7.2   3.9 | -31.3 -24.3  280  77 40   7.3   4.0
 26000 -28.3 -18.9  280  68 35   7.2   4.0 | -29.1 -20.4  280  75 39   7.3   4.0
 25000 -26.1 -15.0  280  66 34   7.2   4.0 | -26.9 -16.4  280  73 38   7.3   4.0
 24000 -23.9 -11.0  280  63 33   8.4   4.6 | -24.7 -12.5  280  68 35   8.4   4.6
 23000 -21.4  -6.5  275  54 28   8.4   4.6 | -22.2  -8.0  270  53 27   8.3   4.6
 22000 -18.9  -2.0  270  45 23   8.4   4.6 | -19.7  -3.5  255  39 20   8.3   4.6
 21000 -16.4   2.5  265  40 21   7.3   4.0 | -17.3   0.9  245  33 17   7.8   4.3
 20000 -14.2   6.4  265  42 22   7.4   4.1 | -15.0   5.0  250  34 17   7.8   4.3
 19500 -13.1   8.4  270  44 23   7.4   4.1 | -13.8   7.2  250  34 18   7.8   4.3
 19000 -12.0  10.4  270  45 23   7.5   4.1 | -12.6   9.3  255  35 18   7.8   4.3
 18500 -10.9  12.4  270  46 24   7.0   3.9 | -11.4  11.5  260  36 18   8.2   4.5
 18000  -9.9  14.2  270  46 24   6.9   3.8 | -10.2  13.6  260  37 19   8.2   4.5
 17500  -8.4  16.9  270  46 24   6.1   3.3 |  -9.0  15.8  265  39 20   7.9   4.3
 17000  -7.5  18.5  270  45 23   5.9   3.2 |  -7.9  17.8  265  41 21   7.3   4.0
 16500  -6.6  20.1  270  44 23   6.0   3.3 |  -6.8  19.8  270  42 22   7.3   4.0
 16000  -5.7  21.7  270  43 22   6.1   3.4 |  -5.7  21.7  270  43 22   6.6   3.6
 15500  -4.8  23.4  275  41 21   6.1   3.4 |  -4.8  23.4  270  43 22   6.6   3.6
 15000  -3.9  25.0  275  39 20   6.4   3.5 |  -3.3  26.1  275  42 22   6.0   3.3
 14500  -3.0  26.6  275  37 19   6.4   3.5 |  -2.5  27.5  275  40 21   6.0   3.3
 14000  -2.0  28.4  275  37 19   7.2   3.9 |  -1.6  29.1  275  39 20   5.9   3.2
 13500  -0.9  30.4  275  39 20   7.3   4.0 |  -0.7  30.7  275  38 20   5.9   3.2
 13000   0.1  32.2  275  40 21   6.0   3.3 |   0.1  32.2  275  37 19   5.9   3.3
 12500   0.9  33.6  275  37 19   5.5   3.0 |   1.0  33.8  275  34 17   6.0   3.3
 12000   1.7  35.1  275  33 17   6.3   3.4 |   1.8  35.2  280  32 16   6.6   3.6
 11500   2.7  36.9  275  32 16   7.0   3.8 |   2.9  37.2  275  37 19   6.9   3.8
 11000   3.7  38.7  275  30 16   6.5   3.5 |   3.8  38.8  275  43 22   5.2   2.8
 10500   4.6  40.3  270  26 13   5.2   2.9 |   4.4  39.9  275  39 20   3.0   1.7
 10250   5.1  41.2  270  24 12   8.6   4.7 |   4.6  40.3  275  37 19   7.8   4.3
 10000   5.8  42.4  270  22 11   9.5   5.2 |   5.4  41.7  275  37 19   9.5   5.2
  9750   6.4  43.5  265  20 10   6.6   3.6 |   5.9  42.6  275  35 18   5.8   3.2
  9500   6.9  44.4  265  18  9   7.6   4.2 |   6.3  43.3  270  34 17   6.8   3.8
  9250   7.5  45.5  260  16  8   6.5   3.6 |   6.8  44.2  270  32 16   6.4   3.5
  9000   7.9  46.2  255  14  7   7.4   4.1 |   7.3  45.1  270  29 15   7.9   4.4
  8750   8.6  47.5  250  12  6   8.9   4.9 |   8.0  46.4  270  28 14   9.3   5.1
  8500   9.2  48.6  245  11  6   8.5   4.7 |   8.6  47.5  270  26 13   8.7   4.8
  8250   9.9  49.8  235  10  5   8.7   4.8 |   9.3  48.7  270  24 12   9.7   5.3
  8000  10.5  50.9  230   9  4   8.8   4.8 |  10.1  50.2  270  22 11  10.2   5.6
  7750  11.2  52.2  225   8  4   8.8   4.8 |  10.8  51.4  270  20 10   8.9   4.9
  7500  11.8  53.2  220   8  4   8.4   4.6 |  11.4  52.5  270  19 10   8.3   4.6
  7250  12.5  54.5  215   8  4   9.6   5.3 |  12.0  53.6  270  17  9   9.1   5.0
  7000  13.3  55.9  215   8  4  11.0   6.0 |  12.8  55.0  270  16  8   9.7   5.3
  6750  14.1  57.4  215   7  4   9.8   5.4 |  13.5  56.3  270  14  7   8.7   4.8
  6500  14.8  58.6  215   7  4   9.3   5.1 |  14.1  57.4  270  12  6   8.3   4.6
  6250  15.5  59.9  215   7  4  10.0   5.5 |  14.7  58.5  270  11  6   9.1   5.0
  6000  16.3  61.3  215   7  4  10.5   5.7 |  15.4  59.7  265   9  5   9.1   5.0
  5750  17.0  62.6  215   7  3   9.5   5.2 |  16.1  61.0  265   8  4   9.6   5.3
  5500  17.7  63.9  215   6  3  10.2   5.6 |  16.7  62.1  260   7  4   4.0   2.2
________________________________________________________________________________

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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