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678
UXUS97 KBOU 020009
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1809 MDT Monday, September 1, 2014

This forecast is for Tuesday, September 2, 2014:

If the trigger temperature of 72.7 F/22.6 C is reached...then
   Thermal Soaring Index....................... Good
   Maximum rate of lift........................ 734 ft/min (3.7 m/s)
   Maximum height of thermals.................. 14720 ft MSL (9433 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 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................. 12057 ft MSL (6770 ft AGL)
Thermal soaring outlook for Wednesday 09/03.... Excellent

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....................... 46383 ft MSL (41096 ft AGL)
Wave soaring outlook for Wednesday 09/03....... Poor

Remarks...

Sunrise/Sunset.................... 06:28:26 / 19:30:29 MDT
Total possible sunshine........... 13 hr 2 min 2 sec (782 min 2 sec)
Altitude of sun at 12:59:01 MDT... 57.96 degrees

Upper air data from numerical model forecast valid on 09/02/2014 at 0600 MDT

Freezing level.................. 15683 ft MSL (10396 ft AGL)
Convective condensation level... 17131 ft MSL (11844 ft AGL)
Lifted condensation level....... 15815 ft MSL (10527 ft AGL)
Lifted index.................... +0.1
K index......................... +0.4

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  -66.5 -87.7   290   40   21   1.5   0.8      M     M       M      M    M
 45000  -62.4 -80.3   290   46   24   5.6   3.1      M     M       M      M    M
 40000  -53.9 -65.0   290   48   25   6.2   3.4      M     M       M      M    M
 38000  -50.3 -58.5   290   50   26   6.1   3.4      M     M       M      M    M
 36000  -46.6 -51.9   290   52   27   6.2   3.4      M     M       M      M    M
 34000  -42.4 -44.3   290   51   26   7.2   3.9      M     M       M      M    M
 32000  -38.1 -36.6   290   49   25   7.2   3.9      M     M       M      M    M
 30000  -32.7 -26.9   290   48   24   8.3   4.6   42.8 109.0    10.1      M    M
 29000  -30.2 -22.4   290   47   24   8.3   4.6   42.2 108.0     9.8      M    M
 28000  -27.7 -17.9   295   47   24   8.7   4.8   41.8 107.3     9.6      M    M
 27000  -25.0 -13.0   295   45   23   9.0   5.0   41.4 106.6     9.5      M    M
 26000  -22.3  -8.1   295   44   23   9.0   5.0   41.2 106.1     9.3      M    M
 25000  -19.6  -3.3   295   42   22   9.2   5.0   41.0 105.8     9.3      M    M
 24000  -17.4   0.7   295   40   21   6.6   3.6   40.0 104.0     8.6      M    M
 23000  -15.4   4.3   295   37   19   6.7   3.7   38.8 101.9     7.8      M    M
 22000  -13.4   7.9   295   35   18   6.7   3.7   37.8 100.1     7.0      M    M
 21000  -11.4  11.5   290   33   17   7.0   3.8   36.7  98.1     6.1      M    M
 20000   -9.3  15.3   290   31   16   7.0   3.8   35.7  96.3     5.3      M    M
 19500   -8.3  17.1   290   30   15   7.0   3.8   35.3  95.5     5.0      M    M
 19000   -7.2  19.0   285   29   15   7.8   4.3   34.9  94.8     4.6      M    M
 18500   -6.0  21.2   285   28   15   7.9   4.4   34.6  94.2     4.4      M    M
 18000   -4.8  23.4   285   28   14   7.9   4.3   34.3  93.7     4.2      M    M
 17500   -3.6  25.5   285   27   14   7.5   4.1   33.9  93.0     3.9      M    M
 17000   -2.5  27.5   285   26   13   7.6   4.2   33.5  92.4     3.6      M    M
 16500   -1.5  29.3   285   25   13   5.7   3.1   33.1  91.5     3.2      M    M
 16000   -0.7  30.7   285   24   12   5.3   2.9   32.3  90.1     2.5      M    M
 15500    0.1  32.2   285   23   12   4.6   2.5   31.6  88.8     1.8      M    M
 15000    0.8  33.4   285   22   11   3.5   1.9   30.0  86.0     0.3      M    M
 14500    1.3  34.3   285   22   11   5.0   2.7   29.0  84.3    -0.6    714  3.6
 14000    2.0  35.6   285   22   11   5.9   3.2   28.4  83.1    -1.4    677  3.4
 13500    2.8  37.0   285   21   11   7.0   3.8   27.8  82.0    -2.1    639  3.2
 13000    4.0  39.2   280   20   10   8.3   4.6   27.5  81.5    -2.4    590  3.0
 12500    5.1  41.2   275   19   10   8.1   4.4   27.3  81.1    -2.7    539  2.7
 12000    6.2  43.2   270   17    9   6.9   3.8   26.9  80.4    -3.1    493  2.5
 11500    7.2  45.0   265   16    8   6.8   3.7   26.4  79.6    -3.6    448  2.3
 11000    8.1  46.6   255   14    7   6.1   3.3   25.9  78.6    -4.1    406  2.1
 10500    9.0  48.2   245   14    7   4.3   2.4   25.4  77.6    -4.7    364  1.9
 10250    9.2  48.6   240   13    7   2.6   1.4   24.8  76.6    -5.3    351  1.8
 10000    9.5  49.1   235   13    7   5.9   3.2   24.4  75.9    -5.7    335  1.7
  9750   10.0  50.0   230   12    6   7.5   4.1   24.1  75.5    -6.0    313  1.6
  9500   10.5  50.9   225   12    6   5.8   3.2   23.9  75.1    -6.2    291  1.5
  9250   10.8  51.4   220   12    6   2.5   1.4   23.5  74.3    -6.7    275  1.4
  9000   10.9  51.6   215   11    6   2.7   1.5   22.9  73.2    -7.3    263  1.3
  8750   11.2  52.2   215   10    5   3.7   2.0   22.4  72.3    -7.8    248  1.3
  8500   11.4  52.5   210    9    5   3.9   2.2   21.9  71.5    -8.3    233  1.2
  8250   11.7  53.1   205    9    5   4.5   2.5   21.5  70.7    -8.7    216  1.1
  8000   12.1  53.8   200    8    4   5.0   2.7   21.1  70.0    -9.1    198  1.0
  7750   12.5  54.5   190    8    4   6.3   3.4   20.8  69.5    -9.4    177  0.9
  7500   13.0  55.4   180    8    4   5.0   2.7   20.5  68.9    -9.7    156  0.8
  7250   13.3  55.9   170    9    4   3.5   1.9   20.1  68.1   -10.2    141  0.7
  7000   13.5  56.3   160    9    5   4.5   2.4   19.6  67.3   -10.7    125  0.6
  6750   13.8  56.8   155   10    5   3.1   1.7   19.2  66.6   -11.1    109  0.6
  6500   13.9  57.0   155    9    5  -0.7  -0.4   18.6  65.4   -11.8    100  0.5
  6250   13.7  56.7   165    8    4  -1.7  -0.9   17.7  63.8   -12.8     98  0.5
  6000   13.5  56.3   180    8    4  -1.8  -1.0   16.8  62.3   -13.7     96  0.5
  5750   13.3  55.9   200    8    4  -4.8  -2.6   15.9  60.6   -14.7     96  0.5
  5500   12.6  54.7   200    6    3  -7.9  -4.3   14.7  58.4   -16.1    109  0.6

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

           09/02/2014 at 0900 MDT          |       09/02/2014 at 1200 MDT
                                           |
K index... -7.1  LI... +4.3                | K index... -8.8  LI... +1.5
CAPE... 0.0  CIN... M                      | CAPE... +0.9  CIN... -3.2
                                           |
Height Temperature  Wnd WndSpd  Lapse Rate | Temperature  Wnd WndSpd  Lapse Rate
ft MSL deg C deg F  Dir kt m/s  C/km F/kft | deg C deg F  Dir kt m/s  C/km F/kft
--------------------------------------------------------------------------------
 50000 -66.1 -87.0  290  38 20   1.7   0.9 | -66.2 -87.2  290  31 16   2.4   1.3
 45000 -62.1 -79.8  290  44 23   4.9   2.7 | -61.5 -78.7  295  39 20   4.6   2.5
 40000 -54.6 -66.3  290  44 22   6.2   3.4 | -54.5 -66.1  285  40 20   5.8   3.2
 38000 -50.9 -59.6  290  44 23   6.2   3.4 | -51.0 -59.8  285  39 20   5.8   3.2
 36000 -47.2 -53.0  290  45 23   6.2   3.4 | -47.5 -53.5  290  38 20   5.8   3.2
 34000 -42.8 -45.0  290  45 23   7.6   4.2 | -42.9 -45.2  290  39 20   8.2   4.5
 32000 -37.7 -35.9  290  45 23   7.5   4.1 | -37.4 -35.3  290  40 21   8.1   4.4
 30000 -32.7 -26.9  290  41 21   8.5   4.7 | -32.2 -26.0  290  39 20   8.9   4.9
 29000 -30.1 -22.2  285  39 20   8.5   4.7 | -29.5 -21.1  290  38 20   8.9   4.9
 28000 -27.5 -17.5  285  37 19   8.7   4.8 | -26.8 -16.2  290  38 19   8.5   4.6
 27000 -24.9 -12.8  290  36 19   8.9   4.9 | -24.4 -11.9  290  37 19   8.3   4.5
 26000 -22.2  -8.0  290  36 19   8.9   4.9 | -21.9  -7.4  290  36 18   8.3   4.5
 25000 -19.6  -3.3  290  36 18   8.9   4.9 | -19.4  -2.9  290  35 18   8.2   4.5
 24000 -17.3   0.9  290  35 18   7.1   3.9 | -17.3   0.9  285  33 17   6.6   3.6
 23000 -15.2   4.6  290  33 17   7.2   3.9 | -15.3   4.5  285  32 17   6.6   3.6
 22000 -13.0   8.6  290  32 16   7.1   3.9 | -13.3   8.1  285  31 16   6.7   3.7
 21000 -11.0  12.2  290  30 16   6.7   3.7 | -11.2  11.8  280  30 15   7.2   4.0
 20000  -9.0  15.8  290  30 15   6.7   3.7 |  -9.1  15.6  275  28 15   7.2   4.0
 19500  -8.0  17.6  285  29 15   6.7   3.7 |  -8.0  17.6  270  28 14   7.2   3.9
 19000  -6.9  19.6  285  29 15   8.3   4.6 |  -6.9  19.6  270  27 14   8.1   4.4
 18500  -5.6  21.9  285  27 14   8.5   4.7 |  -5.6  21.9  270  26 13   8.1   4.5
 18000  -4.3  24.3  285  26 13   8.3   4.6 |  -4.4  24.1  265  25 13   7.9   4.3
 17500  -3.2  26.2  285  25 13   7.1   3.9 |  -3.3  26.1  270  24 12   7.2   4.0
 17000  -2.1  28.2  285  24 12   7.3   4.0 |  -2.2  28.0  270  23 12   7.2   4.0
 16500  -1.1  30.0  285  22 11   5.2   2.9 |  -1.1  30.0  275  23 12   7.0   3.8
 16000  -0.4  31.3  290  21 11   4.9   2.7 |   0.4  32.7  285  23 12   7.1   3.9
 15500   0.6  33.1  290  19 10   4.3   2.3 |   1.4  34.5  290  23 12   5.9   3.3
 15000   1.2  34.2  285  19 10   4.4   2.4 |   2.3  36.1  290  25 13   6.1   3.3
 14500   1.9  35.4  285  18  9   5.3   2.9 |   3.2  37.8  295  26 13   6.2   3.4
 14000   2.7  36.9  285  18  9   5.8   3.2 |   4.1  39.4  295  28 14   6.3   3.5
 13500   3.5  38.3  280  18  9   6.3   3.5 |   5.0  41.0  300  30 15   6.2   3.4
 13000   4.4  39.9  280  18  9   6.8   3.8 |   5.8  42.4  300  31 16   6.1   3.4
 12500   5.4  41.7  275  17  9   7.4   4.1 |   6.7  44.1  300  32 16   6.6   3.6
 12000   6.5  43.7  270  16  8   8.8   4.8 |   7.7  45.9  300  30 16   7.4   4.1
 11500   7.8  46.0  270  15  8   8.6   4.7 |   8.7  47.7  300  29 15   7.6   4.2
 11000   8.9  48.0  260  14  7   7.5   4.1 |   9.9  49.8  295  25 13   7.7   4.2
 10500  10.1  50.2  255  14  7   4.7   2.6 |  11.0  51.8  290  21 11   3.4   1.8
 10250  10.3  50.5  250  14  7   4.2   2.3 |  11.1  52.0  290  20 11   4.1   2.3
 10000  10.8  51.4  250  14  7   9.0   5.0 |  11.8  53.2  290  18  9  10.5   5.8
  9750  11.5  52.7  245  14  7   9.6   5.3 |  12.5  54.5  290  16  8   9.2   5.1
  9500  12.1  53.8  240  14  7   8.0   4.4 |  13.1  55.6  285  13  7   8.0   4.4
  9250  12.6  54.7  235  13  7   4.9   2.7 |  13.6  56.5  280  12  6   5.5   3.0
  9000  12.9  55.2  230  13  7   5.9   3.2 |  14.1  57.4  280  10  5   7.4   4.1
  8750  13.4  56.1  225  13  7   8.0   4.4 |  14.7  58.5  275   9  4   9.1   5.0
  8500  14.0  57.2  220  13  7   5.9   3.3 |  15.3  59.5  265   7  4   7.7   4.2
  8250  14.3  57.7  215  13  7   4.2   2.3 |  15.8  60.4  255   6  3   6.5   3.6
  8000  14.5  58.1  210  13  7   3.5   1.9 |  16.2  61.2  240   5  3   6.9   3.8
  7750  14.7  58.5  205  12  6   2.1   1.2 |  16.7  62.1  220   5  2   7.2   4.0
  7500  14.9  58.8  200  12  6   2.9   1.6 |  17.3  63.1  200   4  2   8.3   4.5
  7250  15.1  59.2  195  11  6   3.7   2.0 |  17.8  64.0  185   4  2   9.4   5.1
  7000  15.4  59.7  190  10  5   3.4   1.8 |  18.4  65.1  160   4  2   8.9   4.9
  6750  15.6  60.1  180  10  5   3.1   1.7 |  19.0  66.2  150   4  2   9.0   5.0
  6500  15.8  60.4  175  10  5   2.9   1.6 |  19.7  67.5  145   4  2  10.3   5.7
  6250  16.0  60.8  170   9  5   4.1   2.2 |  20.5  68.9  145   4  2  11.5   6.3
  6000  16.2  61.2  170   9  5   0.5   0.3 |  21.3  70.3  140   3  2   9.5   5.2
  5750  16.1  61.0  175   9  4   3.7   2.0 |  22.1  71.8  140   3  2  14.3   7.8
  5500  16.9  62.4  170   6  3  19.4  10.6 |  23.6  74.5  135   3  2  27.3  15.0

           09/02/2014 at 1500 MDT          |       09/02/2014 at 1800 MDT
                                           |
K index... +16.8  LI... +1.3               | K index... +22.3  LI... -0.6
CAPE... 0.0  CIN... M                      | CAPE... +93.0  CIN... -86.8
                                           |
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 -65.8 -86.4  300  21 11   2.2   1.2 | -65.0 -85.0  300  20 10   2.7   1.5
 45000 -61.5 -78.7  305  26 13   4.7   2.6 | -60.2 -76.4  305  24 12   4.5   2.5
 40000 -54.4 -65.9  285  38 20   5.6   3.1 | -53.4 -64.1  300  36 19   4.9   2.7
 38000 -51.0 -59.8  280  37 19   5.6   3.0 | -50.5 -58.9  290  37 19   4.8   2.7
 36000 -47.7 -53.9  280  36 19   5.5   3.0 | -47.6 -53.7  285  38 20   4.9   2.7
 34000 -42.4 -44.3  280  36 19   8.3   4.6 | -42.5 -44.5  280  38 19   8.2   4.5
 32000 -37.4 -35.3  280  37 19   8.2   4.5 | -37.6 -35.7  280  36 19   8.1   4.4
 30000 -32.1 -25.8  280  36 19   8.9   4.9 | -32.4 -26.3  280  35 18   8.8   4.8
 29000 -29.5 -21.1  280  36 18   8.9   4.9 | -29.8 -21.6  280  33 17   8.8   4.8
 28000 -26.8 -16.2  280  35 18   8.6   4.7 | -27.1 -16.8  280  32 17   8.7   4.8
 27000 -24.3 -11.7  280  34 18   8.4   4.6 | -24.5 -12.1  280  31 16   8.6   4.7
 26000 -21.7  -7.1  280  33 17   8.4   4.6 | -21.9  -7.4  280  30 15   8.6   4.7
 25000 -19.2  -2.6  280  32 16   8.3   4.6 | -19.3  -2.7  275  29 15   8.6   4.7
 24000 -17.1   1.2  280  31 16   6.7   3.7 | -17.2   1.0  275  29 15   6.5   3.6
 23000 -15.1   4.8  280  30 16   6.8   3.7 | -15.3   4.5  275  30 15   6.6   3.6
 22000 -13.0   8.6  280  29 15   6.7   3.7 | -13.3   8.1  275  30 16   6.5   3.6
 21000 -11.0  12.2  280  29 15   6.8   3.7 | -11.4  11.5  275  31 16   6.3   3.5
 20000  -9.0  15.8  280  30 15   6.8   3.7 |  -9.6  14.7  275  32 17   6.4   3.5
 19500  -8.0  17.6  280  30 15   6.6   3.6 |  -8.6  16.5  275  33 17   6.4   3.5
 19000  -6.9  19.6  280  30 15   9.1   5.0 |  -7.6  18.3  275  33 17   8.2   4.5
 18500  -5.5  22.1  280  29 15   9.2   5.0 |  -6.4  20.5  275  33 17   8.5   4.6
 18000  -4.1  24.6  280  29 15   8.9   4.9 |  -5.1  22.8  270  32 17   8.4   4.6
 17500  -2.9  26.8  280  29 15   7.7   4.2 |  -4.0  24.8  270  32 16   8.1   4.4
 17000  -1.7  28.9  275  30 15   8.0   4.4 |  -2.2  28.0  270  31 16   8.3   4.6
 16500  -0.4  31.3  275  31 16   4.8   2.7 |  -1.0  30.2  265  30 15   8.6   4.7
 16000   0.2  32.4  275  32 16   5.0   2.8 |   0.2  32.4  265  27 14   8.6   4.7
 15500   1.0  33.8  275  32 17   6.4   3.5 |   1.5  34.7  265  25 13   9.2   5.0
 15000   1.8  35.2  275  31 16   6.6   3.6 |   2.8  37.0  265  24 12   9.1   5.0
 14500   2.7  36.9  275  30 15   8.8   4.8 |   4.2  39.6  265  22 11   9.1   5.0
 14000   4.1  39.4  275  28 14   9.4   5.1 |   5.5  41.9  260  21 11   9.1   5.0
 13500   5.4  41.7  270  26 13   9.3   5.1 |   6.9  44.4  260  20 10   8.9   4.9
 13000   6.8  44.2  270  24 13   9.2   5.1 |   8.2  46.8  260  17  9   8.6   4.7
 12500   8.2  46.8  275  23 12   9.0   4.9 |   9.4  48.9  255  15  8   8.5   4.7
 12000   9.5  49.1  275  22 11   8.4   4.6 |  10.7  51.3  245  14  7   8.3   4.5
 11500  10.8  51.4  275  20 10   8.3   4.6 |  11.9  53.4  235  13  7   8.3   4.5
 11000  11.9  53.4  275  18  9   7.7   4.2 |  13.1  55.6  225  12  6   8.0   4.4
 10500  13.1  55.6  275  16  8   4.6   2.5 |  14.3  57.7  210  12  6   5.4   3.0
 10250  13.3  55.9  275  15  8   4.7   2.6 |  14.6  58.3  210  11  6   6.1   3.4
 10000  13.9  57.0  275  13  7   9.1   5.0 |  15.3  59.5  205  11  6  10.2   5.6
  9750  14.6  58.3  270  11  6   8.1   4.5 |  16.0  60.8  195  11  6   9.3   5.1
  9500  15.2  59.4  270  10  5   7.5   4.1 |  16.7  62.1  190  11  5   9.0   5.0
  9250  15.7  60.3  265   8  4   5.9   3.3 |  17.3  63.1  185  10  5   7.9   4.3
  9000  16.1  61.0  255   6  3   6.6   3.6 |  17.9  64.2  180   9  5   8.1   4.4
  8750  16.6  61.9  240   4  2   6.8   3.7 |  18.5  65.3  175   9  4   8.5   4.7
  8500  17.1  62.8  215   3  1   7.8   4.3 |  19.1  66.4  170   8  4   8.4   4.6
  8250  17.8  64.0  195   3  1  10.0   5.5 |  19.7  67.5  165   7  4   8.3   4.5
  8000  18.5  65.3  185   2  1   9.9   5.4 |  20.3  68.5  160   7  4   8.4   4.6
  7750  19.2  66.6  185   2  1   9.3   5.1 |  20.9  69.6  160   6  3   8.4   4.6
  7500  19.9  67.8  185   2  1   9.9   5.4 |  21.6  70.9  155   6  3   9.1   5.0
  7250  20.7  69.3  185   2  1  10.5   5.8 |  22.3  72.1  155   5  3  10.2   5.6
  7000  21.4  70.5  185   2  1  10.0   5.5 |  23.1  73.6  155   5  3  10.0   5.5
  6750  22.2  72.0  185   2  1   9.4   5.2 |  23.8  74.8  155   5  2   9.6   5.2
  6500  22.9  73.2  185   2  1  10.1   5.6 |  24.5  76.1  155   4  2   9.9   5.4
  6250  23.7  74.7  185   2  1  11.2   6.1 |  25.3  77.5  155   4  2  10.4   5.7
  6000  24.5  76.1  185   2  1   9.8   5.4 |  26.0  78.8  155   4  2  10.0   5.5
  5750  25.3  77.5  190   2  1  13.2   7.3 |  26.8  80.2  155   4  2  10.4   5.7
  5500  26.6  79.9  185   2  1  23.5  12.9 |  27.6  81.7  155   3  2  12.4   6.8
________________________________________________________________________________

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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