Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 010008
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1808 MDT Sunday, August 31, 2014

This forecast is for Monday, September 1, 2014:

If the trigger temperature of 69.9 F/21.1 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 761 ft/min (3.9 m/s)
   Maximum height of thermals.................. 14523 ft MSL (9236 ft AGL)

Forecast maximum temperature................... 79.0 F/26.6 C
Time of trigger temperature.................... 1015 MDT
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................. 11489 ft MSL (6201 ft AGL)
Thermal soaring outlook for Tuesday 09/02...... Good

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 NVA
Potential height of wave....................... 40250 ft MSL (34963 ft AGL)
Wave soaring outlook for Tuesday 09/02......... Poor

Remarks...

Sunrise/Sunset.................... 06:27:30 / 19:32:02 MDT
Total possible sunshine........... 13 hr 4 min 32 sec (784 min 32 sec)
Altitude of sun at 12:59:20 MDT... 58.33 degrees

Upper air data from numerical model forecast valid on 09/01/2014 at 0600 MDT

Freezing level.................. 13536 ft MSL (8249 ft AGL)
Convective condensation level... 13000 ft MSL (7713 ft AGL)
Lifted condensation level....... 13870 ft MSL (8583 ft AGL)
Lifted index.................... +0.5
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  -62.9 -81.2   275   45   23   2.2   1.2      M     M       M      M    M
 45000  -59.1 -74.4   275   68   35   3.0   1.6      M     M       M      M    M
 40000  -54.5 -66.1   270   83   43   5.7   3.1      M     M       M      M    M
 38000  -50.9 -59.6   275   80   41   6.0   3.3      M     M       M      M    M
 36000  -47.3 -53.1   280   77   40   6.0   3.3      M     M       M      M    M
 34000  -42.8 -45.0   280   77   39   8.4   4.6      M     M       M      M    M
 32000  -37.1 -34.8   280   77   40   8.4   4.6      M     M       M      M    M
 30000  -32.2 -26.0   275   76   39   8.1   4.5   43.9 110.9    13.5      M    M
 29000  -29.8 -21.6   275   76   39   8.1   4.5   43.2 109.8    13.2      M    M
 28000  -27.4 -17.3   275   75   39   8.2   4.5   42.8 109.0    12.9      M    M
 27000  -24.9 -12.8   275   73   38   8.3   4.5   42.1 107.8    12.5      M    M
 26000  -22.4  -8.3   275   71   37   8.3   4.5   41.5 106.7    12.2      M    M
 25000  -20.0  -4.0   275   69   35   8.3   4.6   41.0 105.9    12.0      M    M
 24000  -18.0  -0.4   275   66   34   5.7   3.1   39.9 103.9    11.2      M    M
 23000  -16.3   2.7   275   63   32   5.6   3.1   38.4 101.0    10.0      M    M
 22000  -14.6   5.7   280   59   31   5.6   3.1   36.9  98.5     8.9      M    M
 21000  -12.9   8.8   280   55   28   5.8   3.2   35.5  95.9     7.8      M    M
 20000  -11.2  11.8   280   50   26   5.8   3.2   34.1  93.4     6.6      M    M
 19500  -10.3  13.5   280   48   25   5.9   3.2   33.4  92.2     6.1      M    M
 19000   -9.4  15.1   280   45   23   6.2   3.4   32.8  91.1     5.6      M    M
 18500   -8.4  16.9   280   43   22   6.9   3.8   32.3  90.1     5.2      M    M
 18000   -7.4  18.7   280   41   21   7.0   3.8   31.8  89.2     4.8      M    M
 17500   -6.4  20.5   280   39   20   5.6   3.1   31.2  88.2     4.3      M    M
 17000   -5.6  21.9   280   38   19   5.5   3.0   30.5  86.9     3.7      M    M
 16500   -4.8  23.4   280   36   18   5.2   2.9   29.8  85.6     3.1      M    M
 16000   -4.0  24.8   280   34   17   4.7   2.6   28.9  84.1     2.4      M    M
 15500   -3.0  26.6   280   31   16   5.2   2.8   27.7  81.9     1.2      M    M
 15000   -2.2  28.0   280   29   15   5.6   3.1   27.0  80.6     0.5      M    M
 14500   -1.5  29.3   280   27   14   5.8   3.2   26.3  79.4    -0.2    751  3.8
 14000   -0.6  30.9   275   25   13   6.3   3.5   25.7  78.3    -0.8    711  3.6
 13500    0.2  32.4   275   22   12   6.4   3.5   25.1  77.3    -1.4    671  3.4
 13000    1.2  34.2   265   20   10   7.5   4.1   24.7  76.5    -1.9    627  3.2
 12500    2.2  36.0   260   18    9   7.4   4.1   24.3  75.8    -2.4    581  3.0
 12000    3.3  37.9   250   17    9   8.7   4.8   24.1  75.3    -2.7    533  2.7
 11500    4.5  40.1   240   16    8   8.6   4.7   23.9  75.0    -3.0    482  2.5
 11000    5.8  42.4   235   15    8   9.1   5.0   23.7  74.7    -3.3    431  2.2
 10500    7.0  44.6   230   13    7  10.2   5.6   23.6  74.4    -3.5    378  1.9
 10250    7.7  45.9   230   12    6   4.3   2.3   23.5  74.3    -3.6    351  1.8
 10000    7.8  46.0   230   11    6   2.9   1.6   22.8  73.1    -4.2    340  1.7
  9750    8.3  46.9   230   10    5   7.6   4.2   22.6  72.7    -4.4    318  1.6
  9500    8.8  47.8   230    8    4   6.8   3.7   22.4  72.3    -4.6    295  1.5
  9250    9.3  48.7   230    6    3   3.7   2.0   22.1  71.8    -4.9    273  1.4
  9000    9.4  48.9   230    6    3   2.3   1.2   21.5  70.7    -5.5    262  1.3
  8750    9.7  49.5   225    5    2   4.2   2.3   21.0  69.8    -6.0    246  1.2
  8500   10.0  50.0   225    4    2   3.8   2.1   20.5  69.0    -6.4    230  1.2
  8250   10.3  50.5   220    3    2   5.3   2.9   20.1  68.3    -6.8    213  1.1
  8000   10.7  51.3   205    3    1   5.2   2.9   19.8  67.7    -7.2    193  1.0
  7750   11.0  51.8   185    3    1   4.1   2.3   19.4  67.0    -7.6    177  0.9
  7500   11.3  52.3   165    4    2   2.9   1.6   19.0  66.1    -8.1    162  0.8
  7250   11.4  52.5   150    4    2   1.4   0.8   18.4  65.0    -8.8    151  0.8
  7000   11.4  52.5   140    5    3   1.3   0.7   17.7  63.9    -9.5    142  0.7
  6750   11.5  52.7   135    6    3   0.4   0.2   17.0  62.7   -10.2    134  0.7
  6500   11.5  52.7   135    6    3   2.9   1.6   16.4  61.5   -10.9    126  0.6
  6250   11.8  53.2   145    4    2   5.0   2.8   16.0  60.8   -11.4    108  0.6
  6000   12.1  53.8   165    4    2   5.1   2.8   15.6  60.1   -11.8     91  0.5
  5750   12.5  54.5   190    3    2   3.0   1.6   15.2  59.4   -12.2     73  0.4
  5500   12.4  54.3   205    4    2  -3.5  -1.9   14.5  58.1   -13.0     70  0.4

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

           09/01/2014 at 0900 MDT          |       09/01/2014 at 1200 MDT
                                           |
K index... +8.2  LI... +2.2                | K index... +10.1  LI... -0.5
CAPE... 0.0  CIN... -2.2                   | CAPE... +21.9  CIN... -20.5
                                           |
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 -62.0 -79.6  280  37 19   2.2   1.2 | -63.2 -81.8  280  42 21   1.4   0.7
 45000 -58.6 -73.5  285  65 34   2.2   1.2 | -60.4 -76.7  295  75 39   3.1   1.7
 40000 -55.2 -67.4  290  86 44   5.5   3.0 | -55.5 -67.9  300  92 47   8.0   4.4
 38000 -51.4 -60.5  285  86 44   6.4   3.5 | -50.7 -59.3  300  91 47   7.9   4.3
 36000 -47.5 -53.5  285  86 44   6.4   3.5 | -46.0 -50.8  300  90 46   7.9   4.3
 34000 -43.1 -45.6  280  84 43   8.1   4.4 | -41.4 -42.5  295  88 45   7.7   4.2
 32000 -37.6 -35.7  275  82 42   8.1   4.5 | -36.1 -33.0  290  86 44   7.7   4.2
 30000 -32.7 -26.9  275  80 41   8.3   4.5 | -31.6 -24.9  285  84 43   7.4   4.1
 29000 -30.2 -22.4  275  79 41   8.3   4.5 | -29.4 -20.9  285  83 43   7.4   4.1
 28000 -27.7 -17.9  280  78 40   8.3   4.5 | -27.2 -17.0  285  82 42   7.4   4.1
 27000 -25.3 -13.5  275  74 38   8.0   4.4 | -25.1 -13.2  285  78 40   6.9   3.8
 26000 -22.9  -9.2  275  69 36   8.0   4.4 | -23.0  -9.4  285  73 38   6.9   3.8
 25000 -20.5  -4.9  270  64 33   8.0   4.4 | -20.9  -5.6  285  68 35   6.9   3.8
 24000 -18.4  -1.1  270  61 31   6.5   3.6 | -18.8  -1.8  285  64 33   7.3   4.0
 23000 -16.4   2.5  275  59 30   6.5   3.6 | -16.6   2.1  285  61 31   7.3   4.0
 22000 -14.5   5.9  275  57 29   6.5   3.6 | -14.4   6.1  280  57 29   7.5   4.1
 21000 -12.9   8.8  280  53 27   5.0   2.7 | -12.9   8.8  280  53 27   3.5   1.9
 20000 -11.4  11.5  280  48 25   5.0   2.7 | -11.9  10.6  285  49 25   3.6   2.0
 19500 -10.7  12.7  285  46 24   5.0   2.8 | -11.4  11.5  285  47 24   3.9   2.1
 19000  -9.9  14.2  285  44 23   5.0   2.8 | -10.9  12.4  285  45 23   5.6   3.1
 18500  -9.2  15.4  285  44 22   5.0   2.7 |  -9.8  14.4  285  43 22   8.4   4.6
 18000  -8.4  16.9  290  44 22   4.9   2.7 |  -8.5  16.7  285  41 21   8.7   4.8
 17500  -7.6  18.3  290  43 22   6.0   3.3 |  -7.4  18.7  285  40 21   5.4   3.0
 17000  -6.7  19.9  290  40 21   6.0   3.3 |  -6.6  20.1  285  44 23   5.4   3.0
 16500  -5.8  21.6  290  38 19   5.7   3.1 |  -5.8  21.6  285  48 25   5.2   2.8
 16000  -5.0  23.0  290  36 19   5.0   2.8 |  -5.1  22.8  285  47 24   5.0   2.7
 15500  -3.9  25.0  290  34 18   5.8   3.2 |  -4.0  24.8  285  44 23   6.3   3.4
 15000  -3.0  26.6  290  32 16   6.3   3.5 |  -3.0  26.6  285  44 22   6.9   3.8
 14500  -2.1  28.2  290  29 15   6.4   3.5 |  -2.1  28.2  285  43 22   7.1   3.9
 14000  -1.1  30.0  290  27 14   6.6   3.6 |  -1.0  30.2  285  40 21   7.1   3.9
 13500  -0.2  31.6  285  25 13   6.7   3.7 |  -0.0  32.0  285  37 19   7.2   4.0
 13000   0.8  33.4  285  23 12   7.2   3.9 |   1.1  34.0  285  34 17   7.7   4.2
 12500   1.8  35.2  280  20 11   7.1   3.9 |   2.2  36.0  285  31 16   7.7   4.2
 12000   3.0  37.4  280  18 10   8.5   4.7 |   3.4  38.1  285  27 14   8.3   4.6
 11500   4.2  39.6  275  17  9   8.5   4.7 |   4.7  40.5  285  24 12   8.3   4.5
 11000   5.3  41.5  270  15  8   8.2   4.5 |   5.8  42.4  290  21 11   7.4   4.1
 10500   6.5  43.7  260  14  7   8.4   4.6 |   6.9  44.4  290  18  9   6.3   3.4
 10250   7.0  44.6  260  14  7   5.1   2.8 |   7.3  45.1  290  17  9   4.8   2.6
 10000   7.3  45.1  255  13  7   7.2   4.0 |   7.8  46.0  290  16  8   8.1   4.4
  9750   8.0  46.4  255  12  6  11.3   6.2 |   8.5  47.3  290  14  7  10.1   5.5
  9500   8.8  47.8  250  11  6  10.4   5.7 |   9.2  48.6  290  13  7   9.2   5.0
  9250   9.4  48.9  245  11  5   5.8   3.2 |   9.8  49.6  295  11  6   6.3   3.5
  9000   9.7  49.5  245  10  5   3.6   2.0 |  10.2  50.4  295  10  5   6.3   3.5
  8750  10.0  50.0  245   9  5   5.8   3.2 |  10.8  51.4  295   9  5   8.2   4.5
  8500  10.4  50.7  245   8  4   5.0   2.8 |  11.3  52.3  295   7  4   7.6   4.2
  8250  10.7  51.3  240   7  4   4.5   2.5 |  11.9  53.4  295   6  3   7.4   4.1
  8000  11.0  51.8  240   6  3   3.7   2.0 |  12.4  54.3  295   4  2   7.5   4.1
  7750  11.3  52.3  235   5  3   2.8   1.5 |  12.8  55.0  295   2  1   7.8   4.3
  7500  11.4  52.5  225   4  2   2.9   1.6 |  13.3  55.9  000   0  0   8.5   4.6
  7250  11.6  52.9  205   4  2   3.5   1.9 |  13.9  57.0  090   1  0   9.1   5.0
  7000  11.9  53.4  180   4  2   3.3   1.8 |  14.5  58.1  095   1  1   9.2   5.1
  6750  12.0  53.6  160   5  2   2.6   1.4 |  15.2  59.4  095   2  1  10.0   5.5
  6500  12.3  54.1  150   5  3   5.2   2.9 |  15.9  60.6  090   2  1  10.6   5.8
  6250  12.8  55.0  150   5  2   7.9   4.3 |  16.7  62.1  090   2  1  11.3   6.2
  6000  13.3  55.9  150   4  2   6.0   3.3 |  17.5  63.5  085   2  1   9.5   5.2
  5750  13.7  56.7  145   3  1   9.8   5.4 |  18.3  64.9  085   2  1  13.5   7.4
  5500  14.8  58.6  140   2  1  20.2  11.1 |  19.8  67.6  085   2  1  26.2  14.4

           09/01/2014 at 1500 MDT          |       09/01/2014 at 1800 MDT
                                           |
K index... +20.3  LI... +1.0               | K index... +21.0  LI... +0.5
CAPE... 0.0  CIN... -0.3                   | CAPE... +0.9  CIN... -23.1
                                           |
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 -65.1 -85.2  295  43 22   0.7   0.4 | -65.5 -85.9  290  39 20   0.8   0.4
 45000 -62.4 -80.3  300  71 36   5.0   2.8 | -62.7 -80.9  295  61 31   5.0   2.8
 40000 -54.6 -66.3  300  75 38   8.2   4.5 | -54.8 -66.6  285  68 35   8.1   4.5
 38000 -49.8 -57.6  300  76 39   7.9   4.3 | -50.1 -58.2  285  70 36   7.9   4.4
 36000 -45.1 -49.2  300  76 39   7.9   4.3 | -45.3 -49.5  290  73 37   7.9   4.4
 34000 -40.4 -40.7  300  76 39   7.7   4.2 | -40.5 -40.9  295  73 37   8.0   4.4
 32000 -35.8 -32.4  300  75 39   7.7   4.2 | -35.1 -31.2  295  72 37   8.0   4.4
 30000 -30.6 -23.1  295  74 38   7.8   4.3 | -30.7 -23.3  295  68 35   7.1   3.9
 29000 -28.3 -18.9  295  73 38   7.8   4.3 | -28.6 -19.5  295  66 34   7.1   3.9
 28000 -25.9 -14.6  295  73 38   7.6   4.2 | -26.4 -15.5  295  63 33   7.4   4.0
 27000 -23.7 -10.7  295  71 37   7.2   4.0 | -24.1 -11.4  295  61 31   7.9   4.3
 26000 -21.6  -6.9  295  70 36   7.2   4.0 | -21.7  -7.1  300  59 30   7.9   4.3
 25000 -19.4  -2.9  295  68 35   7.4   4.0 | -19.3  -2.7  300  57 29   8.2   4.5
 24000 -17.6   0.3  295  65 33   5.0   2.8 | -17.5   0.5  300  55 28   5.1   2.8
 23000 -16.1   3.0  290  60 31   5.0   2.7 | -16.0   3.2  295  52 27   5.1   2.8
 22000 -14.6   5.7  290  56 29   4.9   2.7 | -14.5   5.9  295  50 26   4.9   2.7
 21000 -12.9   8.8  290  53 27   6.1   3.3 | -12.7   9.1  290  49 25   6.6   3.6
 20000 -11.1  12.0  285  51 26   6.1   3.3 | -10.7  12.7  290  47 24   6.6   3.6
 19500 -10.2  13.6  285  51 26   6.0   3.3 |  -9.7  14.5  290  46 23   6.6   3.6
 19000  -9.3  15.3  285  50 26   5.4   3.0 |  -8.7  16.3  285  45 23   6.3   3.5
 18500  -8.6  16.5  285  48 25   4.7   2.6 |  -7.8  18.0  285  43 22   6.2   3.4
 18000  -8.0  17.6  280  47 24   4.7   2.6 |  -6.9  19.6  285  41 21   6.3   3.5
 17500  -7.3  18.9  280  45 23   5.5   3.0 |  -6.2  20.8  285  39 20   4.1   2.2
 17000  -6.5  20.3  275  45 23   5.6   3.1 |  -5.6  21.9  280  37 19   4.5   2.5
 16500  -5.8  21.6  270  44 23   6.9   3.8 |  -4.9  23.2  275  36 18   6.6   3.6
 16000  -4.6  23.7  270  42 21   7.9   4.3 |  -3.4  25.9  270  33 17   7.8   4.3
 15500  -3.0  26.6  265  39 20   8.6   4.7 |  -2.2  28.0  265  31 16   9.2   5.0
 15000  -1.7  28.9  265  36 19   8.8   4.8 |  -0.9  30.4  265  29 15   9.4   5.1
 14500  -0.4  31.3  265  34 17   8.8   4.8 |   0.5  32.9  265  27 14   9.2   5.1
 14000   0.9  33.6  265  32 16   8.9   4.9 |   1.8  35.2  265  26 13   9.1   5.0
 13500   2.2  36.0  265  30 15   8.8   4.8 |   3.2  37.8  270  25 13   9.1   5.0
 13000   3.4  38.1  265  27 14   8.2   4.5 |   4.5  40.1  270  23 12   9.2   5.0
 12500   4.6  40.3  265  25 13   8.2   4.5 |   5.9  42.6  270  22 11   9.1   5.0
 12000   5.8  42.4  265  22 12   7.8   4.3 |   7.1  44.8  270  20 10   7.9   4.4
 11500   7.0  44.6  265  20 10   7.8   4.3 |   8.3  46.9  275  17  9   8.0   4.4
 11000   8.0  46.4  260  17  9   6.4   3.5 |   9.4  48.9  270  15  8   7.2   4.0
 10500   9.0  48.2  260  13  7   4.2   2.3 |  10.5  50.9  265  12  6   4.8   2.6
 10250   9.2  48.6  260  12  6   5.0   2.7 |  10.8  51.4  265  11  6   5.6   3.1
 10000   9.8  49.6  255  10  5   8.6   4.7 |  11.4  52.5  260   9  5   9.6   5.2
  9750  10.4  50.7  250   8  4   7.7   4.2 |  12.1  53.8  255   7  4   8.7   4.7
  9500  11.0  51.8  245   6  3   7.8   4.3 |  12.7  54.9  245   6  3   8.4   4.6
  9250  11.5  52.7  235   4  2   6.0   3.3 |  13.2  55.8  235   4  2   5.6   3.1
  9000  11.9  53.4  230   3  1   6.8   3.7 |  13.6  56.5  235   3  2   5.8   3.2
  8750  12.5  54.5  220   2  1   8.3   4.5 |  14.0  57.2  230   2  1   7.2   4.0
  8500  13.0  55.4  180   1  0   8.3   4.5 |  14.5  58.1  000   0  0   7.3   4.0
  8250  13.7  56.7  120   1  0   9.8   5.4 |  15.1  59.2  060   1  1   8.4   4.6
  8000  14.4  57.9  100   1  0  10.0   5.5 |  15.7  60.3  055   2  1   9.2   5.1
  7750  15.1  59.2  090   1  0   9.3   5.1 |  16.4  61.5  055   2  1   9.5   5.2
  7500  15.8  60.4  085   1  0  10.0   5.5 |  17.1  62.8  050   2  1   9.7   5.3
  7250  16.6  61.9  080   1  0  10.9   6.0 |  17.9  64.2  050   2  1  10.1   5.6
  7000  17.4  63.3  075   1  0  10.5   5.8 |  18.6  65.5  045   2  1   9.9   5.4
  6750  18.2  64.8  070   1  0   9.2   5.0 |  19.3  66.7  045   2  1   9.0   5.0
  6500  18.9  66.0  065   1  0   9.9   5.4 |  20.0  68.0  040   2  1   9.8   5.4
  6250  19.7  67.5  055   1  0  11.6   6.3 |  20.8  69.4  040   2  1  10.9   6.0
  6000  20.5  68.9  050   1  0   9.9   5.4 |  21.6  70.9  035   2  1  10.1   5.6
  5750  21.2  70.2  045   1  0  12.7   7.0 |  22.3  72.1  030   2  1  10.4   5.7
  5500  22.6  72.7  045   1  1  23.5  12.9 |  23.2  73.8  030   2  1  13.0   7.2
________________________________________________________________________________

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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