Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240127
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1927 MDT Saturday, September 23, 2017

This forecast is for Sunday, September 24, 2017:

If the trigger temperature of 57.4 F/14.1 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 249 ft/min (1.3 m/s)
   Maximum height of thermals.................. 8461 ft MSL (3154 ft AGL)

Forecast maximum temperature................... 53.0 F/12.1 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................. 6903 ft MSL (1596 ft AGL)
Thermal soaring outlook for Monday 09/25....... Fair

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 40063 ft MSL (34756 ft AGL)
Wave soaring outlook for Monday 09/25.......... Poor

Remarks...

Sunrise/Sunset.................... 06:49:17 / 18:54:19 MDT
Total possible sunshine........... 12 hr 5 min 2 sec (725 min 2 sec)
Altitude of sun at 12:51:19 MDT... 49.48 degrees

Upper air data from numerical model forecast valid on 09/24/2017 at 0600 MDT

Freezing level.................. 11751 ft MSL (6444 ft AGL)
Convective condensation level... 11665 ft MSL (6358 ft AGL)
Lifted condensation level....... 8670 ft MSL (3363 ft AGL)
Lifted index.................... +6.9
K index......................... +24.2

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  -60.3 -76.5   205   63   32   1.4   0.8      M     M       M      M    M
 45000  -57.6 -71.7   205   90   46   3.7   2.0      M     M       M      M    M
 40000  -52.1 -61.8   200   97   50   3.5   1.9      M     M       M      M    M
 38000  -48.7 -55.7   195   98   51   5.9   3.2      M     M       M      M    M
 36000  -45.2 -49.4   190  100   51   5.9   3.2      M     M       M      M    M
 34000  -40.8 -41.4   190   99   51   7.0   3.8      M     M       M      M    M
 32000  -36.6 -33.9   190   97   50   7.0   3.8      M     M       M      M    M
 30000  -32.6 -26.7   190   95   49   6.4   3.5   45.0 113.0    25.2      M    M
 29000  -30.7 -23.3   190   93   48   6.4   3.5   43.6 110.5    24.5      M    M
 28000  -28.8 -19.8   190   91   47   6.4   3.5   42.4 108.3    23.8      M    M
 27000  -27.1 -16.8   195   88   45   4.1   2.2   40.9 105.6    22.9      M    M
 26000  -25.8 -14.4   195   83   43   4.2   2.3   38.7 101.7    21.5      M    M
 25000  -24.5 -12.1   200   77   40   4.2   2.3   36.7  98.0    20.1      M    M
 24000  -23.2  -9.8   200   72   37   6.0   3.3   34.8  94.7    18.8      M    M
 23000  -21.2  -6.2   205   66   34   6.5   3.5   33.5  92.3    17.9      M    M
 22000  -19.3  -2.7   205   61   31   6.5   3.6   32.3  90.2    17.2      M    M
 21000  -17.3   0.9   205   56   29   7.0   3.8   31.3  88.3    16.4      M    M
 20000  -15.3   4.5   205   51   26   7.0   3.8   30.2  86.4    15.7      M    M
 19500  -14.2   6.4   205   49   25   7.0   3.8   29.7  85.5    15.4      M    M
 19000  -13.2   8.2   205   47   24   7.0   3.9   29.3  84.7    15.1      M    M
 18500  -12.2  10.0   205   45   23   5.9   3.2   28.8  83.9    14.7      M    M
 18000  -11.1  12.0   200   42   22   5.5   3.0   27.7  81.8    13.7      M    M
 17500  -10.3  13.5   200   40   21   5.3   2.9   26.9  80.5    13.1      M    M
 17000   -9.6  14.7   200   39   20   5.3   2.9   26.2  79.1    12.4      M    M
 16500   -8.9  16.0   200   37   19   5.5   3.0   25.4  77.7    11.7      M    M
 16000   -8.1  17.4   200   36   19   5.8   3.2   24.7  76.5    11.1      M    M
 15500   -7.2  19.0   205   35   18   5.6   3.1   24.1  75.3    10.6      M    M
 15000   -6.3  20.7   205   34   17   7.5   4.1   23.5  74.3    10.1      M    M
 14500   -5.2  22.6   210   32   17   7.4   4.1   23.1  73.6     9.8      M    M
 14000   -4.1  24.6   210   31   16   7.4   4.0   22.7  72.9     9.5      M    M
 13500   -3.0  26.6   210   27   14   7.3   4.0   22.3  72.2     9.1      M    M
 13000   -2.0  28.4   210   24   12   6.7   3.7   22.0  71.5     8.8      M    M
 12500   -1.1  30.0   205   20   10   6.2   3.4   21.4  70.5     8.2      M    M
 12000   -0.3  31.5   200   16    8   5.4   3.0   20.8  69.5     7.7      M    M
 11500    0.4  32.7   195   13    7   4.6   2.5   20.0  68.0     6.8      M    M
 11000    1.0  33.8   185   10    5   4.3   2.4   19.2  66.5     6.1      M    M
 10500    1.6  34.9   175    7    4   3.5   1.9   18.2  64.8     5.2      M    M
 10250    1.9  35.4   170    6    3   6.1   3.4   17.8  64.0     4.8      M    M
 10000    2.3  36.1   150    4    2   2.9   1.6   17.5  63.6     4.5      M    M
  9750    2.2  36.0   140    3    2  -2.1  -1.2   16.7  62.0     3.7      M    M
  9500    2.2  36.0   115    2    1  -0.7  -0.4   15.8  60.5     2.9      M    M
  9250    2.1  35.8   080    2    1  -1.4  -0.8   15.0  59.0     2.2      M    M
  9000    2.0  35.6   045    2    1  -0.6  -0.3   14.1  57.4     1.4      M    M
  8750    2.1  35.8   010    2    1   1.7   0.9   13.4  56.1     0.7      M    M
  8500    2.2  36.0   355    3    2   2.1   1.1   12.8  55.1     0.1      M    M
  8250    2.4  36.3   345    4    2   3.3   1.8   12.2  54.0    -0.4    240  1.2
  8000    2.8  37.0   360    5    3   6.0   3.3   11.9  53.4    -0.8    222  1.1
  7750    3.2  37.8   020    7    3   5.1   2.8   11.6  52.8    -1.1    202  1.0
  7500    3.5  38.3   035    8    4   4.4   2.4   11.2  52.1    -1.6    185  0.9
  7250    3.8  38.8   045   10    5   2.5   1.4   10.7  51.3    -2.0    169  0.9
  7000    3.9  39.0   040    9    5   0.7   0.4   10.0  50.1    -2.7    159  0.8
  6750    3.9  39.0   035    8    4   0.4   0.2    9.4  48.9    -3.3    149  0.8
  6500    4.0  39.2   020    7    4   3.0   1.7    8.7  47.7    -4.0    140  0.7
  6250    4.4  39.9   010    6    3   8.3   4.5    8.4  47.2    -4.3    119  0.6
  6000    5.1  41.2   005    5    3   9.4   5.1    8.4  47.1    -4.4     93  0.5
  5750    5.7  42.3   360    4    2   8.6   4.7    8.3  47.0    -4.5     66  0.3
  5500    6.4  43.5   360    3    2  10.4   5.7    8.3  46.9    -4.6     39  0.2

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

           09/24/2017 at 0900 MDT          |       09/24/2017 at 1200 MDT
                                           |
K index... +22.8  LI... +0.7               | K index... +2.3  LI... +1.7
CAPE... +34.0  CIN... -3.7                 | CAPE... 0.0  CIN... -1.4
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -59.7 -75.5  195  59 30   2.0   1.1 | -59.1 -74.4  205  55 28   1.3   0.7
 45000 -56.3 -69.3  205  83 43   3.6   2.0 | -56.7 -70.1  210  76 39   3.6   2.0
 40000 -50.9 -59.6  200  93 48   3.5   1.9 | -51.3 -60.3  210  91 47   3.5   1.9
 38000 -48.3 -54.9  200  96 49   4.4   2.4 | -48.5 -55.3  205  94 48   4.8   2.6
 36000 -45.3 -49.5  195  99 51   4.4   2.4 | -45.3 -49.5  205  97 50   4.8   2.6
 34000 -42.0 -43.6  195 100 51   6.7   3.7 | -42.0 -43.6  205  96 50   6.1   3.3
 32000 -38.0 -36.4  190  99 51   6.7   3.7 | -38.3 -36.9  210  93 48   6.1   3.3
 30000 -34.0 -29.2  190  96 49   6.7   3.7 | -34.6 -30.3  210  88 45   6.1   3.3
 29000 -31.9 -25.4  190  93 48   6.7   3.7 | -32.8 -27.0  210  85 44   6.1   3.3
 28000 -29.9 -21.8  190  91 47   6.7   3.7 | -31.0 -23.8  210  83 42   6.1   3.3
 27000 -28.0 -18.4  195  88 45   4.6   2.5 | -29.2 -20.6  210  80 41   6.1   3.4
 26000 -26.6 -15.9  195  83 43   4.9   2.7 | -27.3 -17.1  210  77 40   6.1   3.4
 25000 -25.1 -13.2  200  79 40   4.9   2.7 | -25.5 -13.9  210  75 39   6.1   3.4
 24000 -23.7 -10.7  200  74 38   5.5   3.0 | -23.6 -10.5  210  72 37   6.1   3.4
 23000 -21.9  -7.4  205  67 34   5.8   3.2 | -21.8  -7.2  210  68 35   6.1   3.4
 22000 -20.2  -4.4  205  60 31   5.8   3.2 | -20.0  -4.0  210  63 33   6.1   3.4
 21000 -18.4  -1.1  210  54 28   6.9   3.8 | -18.1  -0.6  210  59 30   6.0   3.3
 20000 -16.3   2.7  210  48 25   6.9   3.8 | -16.3   2.7  215  54 28   6.0   3.3
 19500 -15.3   4.5  210  46 23   6.9   3.8 | -15.5   4.1  215  52 27   6.0   3.3
 19000 -14.3   6.3  210  43 22   6.9   3.8 | -14.6   5.7  215  50 26   6.1   3.3
 18500 -13.3   8.1  210  40 21   5.6   3.1 | -13.6   7.5  215  48 25   6.8   3.7
 18000 -12.2  10.0  205  38 19   4.8   2.6 | -12.0  10.4  215  44 23   7.2   4.0
 17500 -11.5  11.3  205  36 19   5.1   2.8 | -11.0  12.2  215  41 21   5.5   3.0
 17000 -10.7  12.7  205  34 18   5.4   3.0 | -10.3  13.5  215  38 20   4.8   2.6
 16500 -10.0  14.0  200  32 17   5.5   3.0 |  -9.6  14.7  220  35 18   5.1   2.8
 16000  -9.2  15.4  200  30 16   5.3   2.9 |  -8.7  16.3  215  33 17   6.5   3.6
 15500  -8.5  16.7  200  28 15   5.2   2.9 |  -7.7  18.1  215  30 16   6.4   3.5
 15000  -7.6  18.3  200  26 14   7.8   4.3 |  -6.7  19.9  215  29 15   6.6   3.6
 14500  -6.6  20.1  200  25 13   7.7   4.2 |  -5.8  21.6  215  27 14   6.6   3.6
 14000  -5.5  22.1  200  23 12   8.3   4.5 |  -4.8  23.4  215  26 14   6.3   3.5
 13500  -4.3  24.3  200  21 11   8.4   4.6 |  -4.0  24.8  215  26 13   6.4   3.5
 13000  -3.1  26.4  200  19 10   7.2   3.9 |  -3.1  26.4  210  26 13   7.0   3.8
 12500  -2.2  28.0  200  17  9   6.5   3.5 |  -2.1  28.2  210  24 12   7.2   4.0
 12000  -1.3  29.7  195  14  7   6.2   3.4 |  -1.1  30.0  205  22 11   6.3   3.4
 11500  -0.4  31.3  190  13  6   6.0   3.3 |  -0.4  31.3  205  19 10   5.4   3.0
 11000   0.4  32.7  180  11  6   5.7   3.1 |   0.3  32.5  205  17  9   4.9   2.7
 10500   1.2  34.2  170   9  4   5.3   2.9 |   0.8  33.4  200  13  7   5.5   3.0
 10250   1.6  34.9  165   8  4   5.7   3.1 |   1.1  34.0  195  12  6   0.1   0.1
 10000   1.9  35.4  160   7  4   1.5   0.8 |   0.9  33.6  190  11  6  -0.2  -0.1
  9750   1.8  35.2  160   5  3  -2.0  -1.1 |   1.2  34.2  190   9  5   4.9   2.7
  9500   1.7  35.1  165   4  2  -1.2  -0.6 |   1.5  34.7  190   7  4   3.7   2.0
  9250   1.7  35.1  180   2  1  -1.1  -0.6 |   1.7  35.1  185   5  3   3.3   1.8
  9000   1.7  35.1  240   1  1   1.5   0.8 |   1.9  35.4  190   4  2  -0.4  -0.2
  8750   1.9  35.4  280   2  1   3.2   1.7 |   1.8  35.2  200   2  1  -2.1  -1.2
  8500   2.1  35.8  305   3  1   2.9   1.6 |   1.6  34.9  000   0  0  -2.3  -1.3
  8250   2.3  36.1  315   4  2   3.2   1.7 |   1.5  34.7  005   1  1  -0.2  -0.1
  8000   2.5  36.5  350   3  2   3.4   1.8 |   1.6  34.9  050   3  2   3.2   1.7
  7750   2.7  36.9  025   5  2   1.3   0.7 |   1.9  35.4  065   5  3   2.8   1.6
  7500   2.8  37.0  035   6  3  -0.3  -0.2 |   2.1  35.8  065   6  3   2.5   1.4
  7250   2.8  37.0  035   7  4   2.0   1.1 |   2.3  36.1  065   7  4   4.8   2.7
  7000   3.0  37.4  025   7  4   3.0   1.6 |   2.7  36.9  060   8  4   6.2   3.4
  6750   3.3  37.9  010   8  4   4.1   2.3 |   3.2  37.8  050   8  4   6.5   3.6
  6500   3.7  38.7  005   9  4   7.5   4.1 |   3.7  38.7  045   8  4   8.8   4.8
  6250   4.3  39.7  005   8  4   9.2   5.1 |   4.4  39.9  040   8  4  10.1   5.6
  6000   4.9  40.8  360   8  4   9.4   5.2 |   5.1  41.2  035   7  4  10.0   5.5
  5750   5.6  42.1  360   7  4   9.7   5.3 |   5.9  42.6  030   7  3  10.7   5.9
  5500   6.4  43.5  360   6  3  12.2   6.7 |   6.8  44.2  030   6  3  14.2   7.8

           09/24/2017 at 1500 MDT          |       09/24/2017 at 1800 MDT
                                           |
K index... +1.3  LI... +2.1                | K index... +13.4  LI... +2.4
CAPE... 0.0  CIN... 0.0                    | CAPE... +0.5  CIN... -3.8
                                           |
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  210  50 26   1.4   0.8 | -59.2 -74.6  215  51 26   0.9   0.5
 45000 -57.1 -70.8  215  73 37   2.8   1.6 | -57.3 -71.1  220  67 34   3.4   1.9
 40000 -52.8 -63.0  210  89 46   2.6   1.4 | -52.3 -62.1  215  81 42   3.2   1.8
 38000 -50.1 -58.2  210  91 47   4.8   2.6 | -49.6 -57.3  210  84 43   4.6   2.5
 36000 -46.9 -52.4  210  92 48   4.8   2.6 | -46.8 -52.2  210  85 44   4.6   2.5
 34000 -43.2 -45.8  210  93 48   7.2   3.9 | -43.1 -45.6  210  86 44   6.3   3.5
 32000 -38.9 -38.0  210  93 48   7.2   3.9 | -39.3 -38.7  210  86 44   6.3   3.5
 30000 -34.5 -30.1  210  92 47   7.4   4.1 | -35.3 -31.5  210  86 44   7.2   4.0
 29000 -32.2 -26.0  215  91 47   7.4   4.1 | -33.1 -27.6  215  86 44   7.2   4.0
 28000 -30.0 -22.0  215  90 46   7.4   4.1 | -30.9 -23.6  215  86 44   7.2   4.0
 27000 -27.9 -18.2  215  89 46   6.0   3.3 | -28.8 -19.8  215  85 44   7.1   3.9
 26000 -26.1 -15.0  215  86 44   6.1   3.3 | -26.6 -15.9  215  83 43   7.2   3.9
 25000 -24.3 -11.7  220  83 43   6.1   3.3 | -24.5 -12.1  215  81 42   7.2   3.9
 24000 -22.4  -8.3  220  81 41   7.0   3.8 | -22.3  -8.1  215  79 41   7.3   4.0
 23000 -20.3  -4.5  220  76 39   7.1   3.9 | -20.1  -4.2  215  75 39   7.3   4.0
 22000 -18.1  -0.6  220  71 37   7.1   3.9 | -17.9  -0.2  220  72 37   7.3   4.0
 21000 -16.1   3.0  220  67 34   5.0   2.7 | -15.9   3.4  220  67 35   4.5   2.5
 20000 -14.6   5.7  220  61 31   5.2   2.8 | -14.5   5.9  220  62 32   4.8   2.6
 19500 -13.8   7.2  220  58 30   5.2   2.9 | -13.8   7.2  225  59 30   4.8   2.6
 19000 -13.0   8.6  220  55 28   5.2   2.8 | -13.1   8.4  225  56 29   4.8   2.6
 18500 -12.2  10.0  225  52 27   5.6   3.1 | -12.4   9.7  225  53 27   4.5   2.5
 18000 -11.0  12.2  225  49 25   5.7   3.1 | -11.4  11.5  225  49 25   4.4   2.4
 17500 -10.1  13.8  225  47 24   5.8   3.2 | -10.8  12.6  230  45 23   4.0   2.2
 17000  -9.2  15.4  225  45 23   5.9   3.2 | -10.2  13.6  230  42 22   3.9   2.1
 16500  -8.4  16.9  225  43 22   5.7   3.2 |  -9.7  14.5  230  39 20   4.4   2.4
 16000  -7.6  18.3  225  40 21   5.3   2.9 |  -8.9  16.0  230  36 19   5.6   3.1
 15500  -6.8  19.8  225  38 20   5.3   2.9 |  -8.2  17.2  225  33 17   5.4   3.0
 15000  -6.0  21.2  225  36 18   5.8   3.2 |  -7.1  19.2  225  32 16   8.6   4.7
 14500  -5.1  22.8  225  34 17   5.8   3.2 |  -5.9  21.4  220  31 16   8.3   4.5
 14000  -4.3  24.3  225  32 17   5.2   2.9 |  -4.7  23.5  215  31 16   8.2   4.5
 13500  -3.7  25.3  220  30 16   5.3   2.9 |  -3.6  25.5  210  30 15   8.3   4.6
 13000  -2.9  26.8  215  28 15   6.3   3.5 |  -2.4  27.7  205  29 15   7.3   4.0
 12500  -2.0  28.4  210  26 13   6.8   3.7 |  -1.5  29.3  205  27 14   6.9   3.8
 12000  -1.0  30.2  205  24 12   6.7   3.7 |  -0.6  30.9  200  24 12   5.4   3.0
 11500  -0.2  31.6  200  21 11   6.5   3.6 |   0.1  32.2  195  22 12   4.5   2.5
 11000   0.6  33.1  190  18  9   3.6   2.0 |   0.6  33.1  190  21 11   1.7   1.0
 10500   0.8  33.4  185  13  7   1.1   0.6 |   0.5  32.9  190  18  9   0.3   0.1
 10250   0.9  33.6  185  11  6   1.5   0.8 |   0.5  32.9  185  17  9  -1.6  -0.9
 10000   1.0  33.8  185  10  5   0.5   0.3 |   0.4  32.7  185  16  8   0.9   0.5
  9750   0.9  33.6  185   8  4  -1.0  -0.5 |   0.7  33.3  185  14  7   4.3   2.4
  9500   0.9  33.6  185   6  3  -0.5  -0.3 |   0.9  33.6  185  11  6   3.8   2.1
  9250   0.8  33.4  185   3  2  -0.9  -0.5 |   1.2  34.2  180   9  4   2.6   1.5
  9000   0.7  33.3  190   2  1   0.0   0.0 |   1.3  34.3  185   7  3  -0.1  -0.1
  8750   0.8  33.4  175   2  1   2.2   1.2 |   1.3  34.3  185   5  3   0.5   0.3
  8500   1.0  33.8  130   2  1   3.1   1.7 |   1.3  34.3  185   4  2   1.0   0.5
  8250   1.3  34.3  105   3  2   2.5   1.4 |   1.4  34.5  180   2  1   2.1   1.2
  8000   1.4  34.5  095   5  2   2.1   1.2 |   1.7  35.1  130   3  1   3.9   2.1
  7750   1.6  34.9  090   6  3   3.3   1.8 |   1.9  35.4  100   4  2   3.0   1.6
  7500   1.9  35.4  085   7  4   4.4   2.4 |   2.1  35.8  090   6  3   3.1   1.7
  7250   2.3  36.1  080   7  4   7.0   3.8 |   2.5  36.5  080   6  3   6.5   3.6
  7000   2.9  37.2  065   7  3   9.1   5.0 |   3.0  37.4  070   6  3   8.3   4.6
  6750   3.5  38.3  055   7  3   7.6   4.2 |   3.6  38.5  055   6  3   8.3   4.5
  6500   4.0  39.2  045   7  3   8.6   4.7 |   4.2  39.6  040   6  3   9.2   5.0
  6250   4.7  40.5  040   6  3  10.5   5.8 |   4.9  40.8  035   6  3   9.4   5.2
  6000   5.5  41.9  030   6  3  10.3   5.6 |   5.5  41.9  025   6  3   9.4   5.1
  5750   6.2  43.2  025   6  3  10.4   5.7 |   6.2  43.2  015   6  3   9.4   5.1
  5500   7.1  44.8  025   6  3  12.4   6.8 |   6.9  44.4  010   6  3  11.1   6.1
________________________________________________________________________________

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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