Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 130118
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1918 MDT Friday, September 12, 2014

This forecast is for Saturday, September 13, 2014:

If the trigger temperature of 73.8 F/23.2 C is reached...then
   Thermal Soaring Index....................... Fair
   Maximum rate of lift........................ 385 ft/min (2.0 m/s)
   Maximum height of thermals.................. 10469 ft MSL (5182 ft AGL)

Forecast maximum temperature................... 76.0 F/24.9 C
Time of trigger temperature.................... 1400 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................. 8003 ft MSL (2715 ft AGL)
Thermal soaring outlook for Sunday 09/14....... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Decreasing
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Neither
Potential height of wave....................... 46063 ft MSL (40776 ft AGL)
Wave soaring outlook for Sunday 09/14.......... Poor

Remarks...

Sunrise/Sunset.................... 06:38:41 / 19:12:50 MDT
Total possible sunshine........... 12 hr 34 min 9 sec (754 min 9 sec)
Altitude of sun at 12:55:16 MDT... 53.84 degrees

Upper air data from numerical model forecast valid on 09/13/2014 at 0600 MDT

Freezing level.................. 14508 ft MSL (9221 ft AGL)
Convective condensation level... 20505 ft MSL (15218 ft AGL)
Lifted condensation level....... 17595 ft MSL (12308 ft AGL)
Lifted index.................... +5.7
K index......................... -13.1

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  -64.3 -83.7   280   47   24   2.3   1.3      M     M       M      M    M
 45000  -60.6 -77.1   280   67   34   2.9   1.6      M     M       M      M    M
 40000  -55.8 -68.4   275   65   33   6.9   3.8      M     M       M      M    M
 38000  -51.8 -61.2   275   61   31   6.6   3.6      M     M       M      M    M
 36000  -47.9 -54.2   275   57   29   6.6   3.6      M     M       M      M    M
 34000  -43.1 -45.6   275   56   29   8.5   4.7      M     M       M      M    M
 32000  -38.0 -36.4   275   55   28   8.5   4.7      M     M       M      M    M
 30000  -33.2 -27.8   280   52   27   7.7   4.2   43.5 110.3    14.4      M    M
 29000  -30.9 -23.6   285   50   26   7.7   4.2   42.7 108.8    14.0      M    M
 28000  -28.0 -18.4   290   48   25   7.4   4.1   41.9 107.4    13.5      M    M
 27000  -26.0 -14.8   290   45   23   6.5   3.6   40.6 105.0    12.7      M    M
 26000  -24.1 -11.4   290   41   21   6.5   3.6   39.3 102.7    11.8      M    M
 25000  -22.2  -8.0   290   37   19   6.5   3.6   38.2 100.7    11.1      M    M
 24000  -20.2  -4.4   285   34   18   6.3   3.5   36.9  98.4    10.1      M    M
 23000  -18.4  -1.1   285   32   16   6.3   3.5   35.6  96.1     9.2      M    M
 22000  -16.5   2.3   280   29   15   6.3   3.4   34.5  94.0     8.3      M    M
 21000  -14.5   5.9   280   27   14   6.6   3.6   33.3  91.9     7.4      M    M
 20000  -12.6   9.3   280   25   13   6.7   3.7   32.2  89.9     6.5      M    M
 19500  -11.6  11.1   280   24   12   6.7   3.7   31.6  89.0     6.1      M    M
 19000  -10.6  12.9   275   23   12   7.4   4.1   31.2  88.1     5.7      M    M
 18500   -9.4  15.1   275   23   12   7.8   4.3   30.8  87.5     5.5      M    M
 18000   -8.2  17.2   280   22   11   7.8   4.3   30.5  86.9     5.2      M    M
 17500   -7.1  19.2   280   21   11   7.6   4.1   30.2  86.3     4.9      M    M
 17000   -5.9  21.4   280   21   11   7.6   4.2   29.8  85.6     4.6      M    M
 16500   -4.8  23.4   280   21   11   7.6   4.1   29.4  85.0     4.3      M    M
 16000   -3.7  25.3   285   20   10   7.5   4.1   29.0  84.3     4.0      M    M
 15500   -2.6  27.3   285   20   10   7.6   4.2   28.7  83.6     3.7      M    M
 15000   -1.4  29.5   285   20   10   7.7   4.2   28.3  83.0     3.4      M    M
 14500   -0.3  31.5   290   20   10   7.7   4.2   28.0  82.4     3.1      M    M
 14000    1.4  34.5   290   21   11   7.6   4.2   27.5  81.4     2.6      M    M
 13500    2.6  36.7   290   21   11   7.6   4.2   27.1  80.8     2.3      M    M
 13000    3.7  38.7   290   22   11   7.6   4.2   26.8  80.2     2.0      M    M
 12500    4.8  40.6   290   22   11   7.5   4.1   26.4  79.6     1.7      M    M
 12000    5.9  42.6   290   23   12   7.1   3.9   26.0  78.8     1.3      M    M
 11500    6.9  44.4   290   23   12   7.1   3.9   25.6  78.1     0.9      M    M
 11000    7.9  46.2   290   24   12   6.8   3.7   25.1  77.3     0.4      M    M
 10500    8.9  48.0   290   24   12   5.6   3.0   24.7  76.5    -0.0    383  1.9
 10250    9.3  48.7   290   24   12   4.3   2.4   24.3  75.7    -0.4    366  1.9
 10000    9.7  49.5   290   24   12   7.4   4.0   24.0  75.1    -0.7    346  1.8
  9750   10.3  50.5   290   23   12   9.0   5.0   23.9  74.9    -0.9    320  1.6
  9500   10.9  51.6   290   23   12   7.9   4.3   23.8  74.8    -1.0    294  1.5
  9250   11.4  52.5   285   22   12   5.0   2.7   23.5  74.3    -1.2    272  1.4
  9000   11.7  53.1   285   22   11   5.3   2.9   23.1  73.6    -1.6    256  1.3
  8750   12.2  54.0   285   21   11   7.5   4.1   22.9  73.2    -1.9    233  1.2
  8500   12.7  54.9   285   20   10   5.7   3.1   22.7  72.8    -2.1    211  1.1
  8250   13.0  55.4   285   18    9   3.7   2.0   22.2  72.0    -2.5    194  1.0
  8000   13.3  55.9   285   17    9   3.1   1.7   21.8  71.2    -3.0    179  0.9
  7750   13.5  56.3   285   15    8   3.7   2.1   21.3  70.3    -3.5    165  0.8
  7500   13.7  56.7   285   14    7   0.9   0.5   20.7  69.3    -4.1    152  0.8
  7250   13.6  56.5   290   12    6  -2.0  -1.1   19.9  67.8    -4.9    148  0.8
  7000   13.4  56.1   290   10    5  -0.6  -0.3   19.1  66.3    -5.8    144  0.7
  6750   13.3  55.9   290    9    4  -3.7  -2.0   18.2  64.8    -6.7    141  0.7
  6500   12.7  54.9   290    7    4 -10.4  -5.7   16.9  62.5    -8.0    151  0.8
  6250   11.6  52.9   285    6    3 -17.5  -9.6   15.1  59.3    -9.9    177  0.9
  6000   10.5  50.9   280    5    2  -1.8  -1.0   13.4  56.1   -11.7    202  1.0
  5750   10.6  51.1   275    3    2 -11.7  -6.4   12.8  55.0   -12.4    192  1.0
  5500    7.4  45.3   230    3    1 -70.4 -38.6    9.0  48.1   -16.3    281  1.4

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

           09/13/2014 at 0900 MDT          |       09/13/2014 at 1200 MDT
                                           |
K index... -13.7  LI... +4.4               | K index... -14.6  LI... +4.5
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -63.8 -82.8  280  44 23   3.3   1.8 | -64.3 -83.7  275  44 23   4.2   2.3
 45000 -59.3 -74.7  285  63 33   2.0   1.1 | -58.6 -73.5  280  60 31   2.2   1.2
 40000 -56.0 -68.8  270  68 35   6.6   3.6 | -55.0 -67.0  270  65 33   5.5   3.0
 38000 -52.0 -61.6  270  60 31   6.6   3.6 | -51.8 -61.2  270  61 31   5.5   3.0
 36000 -48.1 -54.6  265  53 27   6.6   3.6 | -48.5 -55.3  270  57 30   5.5   3.0
 34000 -43.6 -46.5  270  51 26   7.9   4.4 | -44.1 -47.4  270  53 28   8.0   4.4
 32000 -38.8 -37.8  275  53 27   8.0   4.4 | -39.4 -38.9  275  49 25   8.0   4.4
 30000 -34.1 -29.4  280  49 25   7.8   4.3 | -34.8 -30.6  275  45 23   7.5   4.1
 29000 -31.2 -24.2  285  46 23   7.8   4.3 | -31.9 -25.4  275  41 21   7.5   4.1
 28000 -28.9 -20.0  285  43 22   7.6   4.2 | -29.7 -21.5  280  38 20   7.7   4.2
 27000 -26.7 -16.1  290  40 21   7.2   3.9 | -27.3 -17.1  280  37 19   8.1   4.4
 26000 -24.6 -12.3  290  38 19   7.2   3.9 | -24.9 -12.8  280  35 18   8.1   4.4
 25000 -22.4  -8.3  290  35 18   7.2   3.9 | -22.4  -8.3  280  33 17   8.2   4.5
 24000 -20.3  -4.5  290  33 17   7.0   3.9 | -20.3  -4.5  280  31 16   6.8   3.8
 23000 -18.2  -0.8  290  30 16   7.0   3.9 | -18.2  -0.8  280  30 15   6.8   3.8
 22000 -16.1   3.0  290  28 14   7.1   3.9 | -16.2   2.8  280  28 14   6.9   3.8
 21000 -14.2   6.4  290  27 14   6.0   3.3 | -14.2   6.4  285  27 14   6.4   3.5
 20000 -12.4   9.7  290  26 13   6.0   3.3 | -12.3   9.9  285  27 14   6.5   3.5
 19500 -11.5  11.3  290  25 13   6.0   3.3 | -11.3  11.7  290  27 14   6.4   3.5
 19000 -10.6  12.9  290  25 13   7.0   3.8 | -10.4  13.3  290  27 14   6.7   3.7
 18500  -9.5  14.9  290  24 13   7.4   4.1 |  -9.4  15.1  290  26 14   6.7   3.7
 18000  -8.4  16.9  290  24 12   7.5   4.1 |  -8.4  16.9  295  26 13   6.8   3.7
 17500  -7.2  19.0  290  24 12   7.9   4.3 |  -7.3  18.9  295  25 13   7.2   4.0
 17000  -6.1  21.0  295  23 12   7.9   4.3 |  -6.2  20.8  295  24 12   7.2   4.0
 16500  -4.9  23.2  295  23 12   7.9   4.3 |  -5.2  22.6  295  23 12   7.2   3.9
 16000  -3.7  25.3  295  22 11   7.9   4.3 |  -4.1  24.6  295  21 11   7.2   3.9
 15500  -2.5  27.5  300  20 11   7.6   4.2 |  -3.0  26.6  295  20 10   7.4   4.1
 15000  -1.5  29.3  300  19 10   7.0   3.9 |  -1.9  28.6  295  18  9   7.7   4.2
 14500   0.1  32.2  305  17  9   7.2   3.9 |  -0.2  31.6  300  16  8   8.1   4.4
 14000   1.2  34.2  310  16  8   7.2   4.0 |   1.1  34.0  305  15  8   8.2   4.5
 13500   2.2  36.0  315  15  8   7.6   4.2 |   2.3  36.1  310  15  8   8.7   4.8
 13000   3.5  38.3  320  15  8   8.3   4.5 |   3.7  38.7  310  18  9   9.2   5.1
 12500   4.7  40.5  320  15  8   8.4   4.6 |   5.1  41.2  310  22 11   8.8   4.8
 12000   5.9  42.6  320  17  9   8.5   4.7 |   6.2  43.2  310  23 12   7.6   4.2
 11500   7.2  45.0  320  18  9   8.4   4.6 |   7.4  45.3  315  23 12   7.8   4.3
 11000   8.4  47.1  320  21 11   7.7   4.2 |   8.6  47.5  310  25 13   8.1   4.5
 10500   9.5  49.1  315  23 12   6.0   3.3 |   9.8  49.6  310  27 14   5.0   2.7
 10250   9.9  49.8  315  24 12   4.3   2.4 |  10.0  50.0  310  27 14   3.8   2.1
 10000  10.3  50.5  310  25 13   7.1   3.9 |  10.5  50.9  310  27 14   8.4   4.6
  9750  10.9  51.6  310  26 13   8.5   4.7 |  11.1  52.0  310  26 14   8.9   4.9
  9500  11.4  52.5  305  27 14   7.4   4.1 |  11.7  53.1  305  26 14   7.4   4.0
  9250  11.9  53.4  305  28 14   5.6   3.1 |  12.1  53.8  305  25 13   4.8   2.7
  9000  12.2  54.0  305  27 14   5.2   2.9 |  12.5  54.5  305  24 12   6.4   3.5
  8750  12.6  54.7  305  27 14   5.9   3.2 |  13.0  55.4  305  22 11   8.2   4.5
  8500  13.0  55.4  300  26 13   5.1   2.8 |  13.5  56.3  305  20 10   6.9   3.8
  8250  13.3  55.9  300  24 13   4.4   2.4 |  13.9  57.0  305  18  9   6.2   3.4
  8000  13.6  56.5  300  22 12   3.8   2.1 |  14.4  57.9  305  16  8   5.7   3.1
  7750  13.8  56.8  300  20 10   3.4   1.9 |  14.7  58.5  305  14  7   4.6   2.5
  7500  14.0  57.2  300  18  9   0.5   0.3 |  15.0  59.0  310  11  6   3.0   1.6
  7250  13.9  57.0  300  15  8  -1.9  -1.0 |  15.1  59.2  310   8  4   2.3   1.3
  7000  13.8  56.8  295  12  6  -1.0  -0.5 |  15.3  59.5  310   4  2   1.3   0.7
  6750  13.7  56.7  295   9  5  -2.8  -1.5 |  15.3  59.5  300   1  0   3.1   1.7
  6500  13.3  55.9  290   7  3  -6.1  -3.4 |  15.8  60.4  135   1  1   9.2   5.0
  6250  12.8  55.0  280   5  2  -6.7  -3.7 |  16.5  61.7  130   1  1  11.0   6.0
  6000  12.2  54.0  260   3  2  -7.8  -4.3 |  17.3  63.1  125   2  1  10.0   5.5
  5750  11.7  53.1  210   3  1  -5.2  -2.9 |  18.2  64.8  125   2  1  14.0   7.7
  5500  11.5  52.7  190   2  1   3.1   1.7 |  19.5  67.1  120   2  1  21.7  11.9

           09/13/2014 at 1500 MDT          |       09/13/2014 at 1800 MDT
                                           |
K index... +0.2  LI... +2.8                | K index... +13.9  LI... +1.2
CAPE... 0.0  CIN... M                      | CAPE... 0.0  CIN... M
                                           |
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 -65.7 -86.3  265  48 25   4.1   2.3 | -65.1 -85.2  275  52 27   4.2   2.3
 45000 -59.6 -75.3  270  61 31   3.8   2.1 | -59.0 -74.2  275  61 31   3.7   2.0
 40000 -53.5 -64.3  270  60 31   4.3   2.3 | -53.1 -63.6  275  54 28   3.5   1.9
 38000 -51.0 -59.8  270  57 30   4.2   2.3 | -51.0 -59.8  275  50 26   3.5   1.9
 36000 -48.4 -55.1  270  55 28   4.3   2.4 | -48.9 -56.0  275  47 24   3.6   2.0
 34000 -44.3 -47.7  270  52 27   8.1   4.4 | -44.8 -48.6  275  45 23   8.2   4.5
 32000 -39.5 -39.1  270  48 24   8.1   4.4 | -39.9 -39.8  275  44 23   8.2   4.5
 30000 -34.8 -30.6  275  43 22   7.7   4.2 | -34.8 -30.6  275  41 21   8.7   4.8
 29000 -31.9 -25.4  275  40 20   7.7   4.2 | -31.5 -24.7  275  38 20   8.7   4.8
 28000 -29.7 -21.5  275  37 19   7.7   4.2 | -28.9 -20.0  275  36 18   8.2   4.5
 27000 -27.3 -17.1  275  34 18   7.7   4.2 | -26.7 -16.1  275  35 18   7.3   4.0
 26000 -25.0 -13.0  275  32 16   7.7   4.2 | -24.5 -12.1  275  34 18   7.3   4.0
 25000 -22.7  -8.9  270  29 15   7.8   4.3 | -22.3  -8.1  275  34 17   7.5   4.1
 24000 -20.6  -5.1  270  28 15   7.0   3.8 | -20.4  -4.7  275  33 17   6.2   3.4
 23000 -18.5  -1.3  270  28 15   7.0   3.8 | -18.5  -1.3  275  33 17   6.2   3.4
 22000 -16.4   2.5  270  29 15   6.9   3.8 | -16.6   2.1  275  32 16   6.2   3.4
 21000 -14.3   6.3  275  28 15   7.2   3.9 | -14.7   5.5  275  32 17   6.5   3.6
 20000 -12.1  10.2  275  28 14   7.2   3.9 | -12.8   9.0  280  33 17   6.5   3.6
 19500 -11.1  12.0  275  28 14   7.2   3.9 | -11.8  10.8  280  33 17   6.5   3.6
 19000 -10.0  14.0  280  28 14   7.1   3.9 | -10.9  12.4  280  33 17   6.8   3.8
 18500  -8.9  16.0  280  29 15   7.1   3.9 |  -9.9  14.2  275  32 17   7.0   3.8
 18000  -7.9  17.8  280  29 15   7.2   3.9 |  -8.9  16.0  275  32 16   7.1   3.9
 17500  -6.8  19.8  285  29 15   7.7   4.2 |  -7.8  18.0  275  31 16   7.6   4.2
 17000  -5.6  21.9  285  29 15   7.7   4.2 |  -6.7  19.9  275  30 16   7.6   4.2
 16500  -4.5  23.9  285  29 15   7.4   4.1 |  -5.6  21.9  270  29 15   8.6   4.7
 16000  -3.4  25.9  285  30 15   7.4   4.0 |  -4.3  24.3  270  28 14   8.7   4.8
 15500  -2.3  27.9  290  30 15   7.2   3.9 |  -3.1  26.4  270  26 14   8.8   4.8
 15000  -1.3  29.7  290  30 15   6.9   3.8 |  -1.8  28.8  275  25 13   8.8   4.8
 14500   0.2  32.4  290  30 15   7.2   4.0 |   0.2  32.4  275  23 12   8.8   4.8
 14000   1.3  34.3  290  29 15   7.4   4.1 |   1.5  34.7  275  22 11   8.8   4.8
 13500   2.4  36.3  290  29 15   7.7   4.2 |   2.8  37.0  275  20 10   8.6   4.7
 13000   3.5  38.3  290  28 14   8.0   4.4 |   4.1  39.4  280  19 10   8.4   4.6
 12500   4.7  40.5  290  26 14   8.4   4.6 |   5.3  41.5  280  17  9   8.4   4.6
 12000   6.0  42.8  290  24 13   9.2   5.0 |   6.6  43.9  280  16  8   8.4   4.6
 11500   7.3  45.1  290  23 12   9.0   4.9 |   7.8  46.0  280  14  7   8.2   4.5
 11000   8.6  47.5  290  21 11   8.0   4.4 |   9.0  48.2  280  12  6   7.3   4.0
 10500   9.9  49.8  295  18 10   4.1   2.3 |  10.1  50.2  285  10  5   3.5   1.9
 10250  10.0  50.0  295  18  9   4.9   2.7 |  10.2  50.4  280  10  5   3.9   2.1
 10000  10.7  51.3  295  17  9  10.9   6.0 |  10.8  51.4  280   7  4   9.3   5.1
  9750  11.4  52.5  300  15  8   9.9   5.4 |  11.4  52.5  270   5  3   8.1   4.4
  9500  12.2  54.0  300  14  7   8.7   4.7 |  12.0  53.6  255   3  2   7.4   4.0
  9250  12.7  54.9  305  12  6   6.0   3.3 |  12.5  54.5  220   2  1   5.7   3.2
  9000  13.1  55.6  305  10  5   6.6   3.6 |  12.9  55.2  165   2  1   7.4   4.0
  8750  13.6  56.5  310   8  4   7.4   4.1 |  13.5  56.3  130   2  1   8.3   4.6
  8500  14.2  57.6  320   5  3   6.7   3.7 |  14.0  57.2  115   3  2   8.7   4.8
  8250  14.6  58.3  340   3  2   5.6   3.1 |  14.7  58.5  110   4  2   9.6   5.3
  8000  14.9  58.8  025   2  1   7.2   4.0 |  15.4  59.7  100   4  2   9.5   5.2
  7750  15.5  59.9  045   3  1   9.1   5.0 |  16.1  61.0  095   4  2   9.5   5.2
  7500  16.2  61.2  055   3  1   9.7   5.3 |  16.8  62.2  095   4  2   9.9   5.4
  7250  16.9  62.4  055   3  1  10.3   5.6 |  17.5  63.5  090   4  2  10.3   5.6
  7000  17.7  63.9  055   3  1  10.2   5.6 |  18.3  64.9  090   5  2   9.8   5.4
  6750  18.5  65.3  055   3  1  10.5   5.8 |  19.0  66.2  085   5  2   9.4   5.2
  6500  19.3  66.7  055   3  2  10.5   5.8 |  19.7  67.5  085   5  2   9.8   5.4
  6250  20.0  68.0  055   3  2  11.1   6.1 |  20.5  68.9  080   4  2  10.5   5.7
  6000  20.8  69.4  055   3  1   9.0   4.9 |  21.2  70.2  080   4  2   9.4   5.2
  5750  21.5  70.7  055   3  1  12.6   6.9 |  21.9  71.4  075   4  2   9.3   5.1
  5500  22.9  73.2  050   3  2  24.8  13.6 |  22.7  72.9  075   4  2  12.0   6.6
________________________________________________________________________________

This product is issued twice per day, once by approximately 0630 MST/0730 MDT
(1330 UTC) and again by approximately 1830 MST/1930 MDT (0130 UTC).  It is not
continuously monitored nor updated after its initial issuance.

The information contained herein is based on rawinsonde observation and/or
numerical weather prediction model data taken near the old Stapleton
Airport site in Denver, Colorado at

                   North Latitude:  39 deg 46 min 5.016 sec
                   West Longitude: 104 deg 52 min 9.984 sec
                   Elevation: 5285 feet (1611 meters)

and may not be representative of other areas along the Front Range of the
Colorado Rocky Mountains.  Note that some elevations in numerical weather
prediction models differ from actual station elevations, which can lead to
data which appear to be below ground.  Erroneous data such as these should
not be used.

The content and format of this report as well as the issuance times are subject
to change without prior notice.  Comments and suggestions are welcome and should
be directed to one of the addresses or phone numbers shown at the bottom of this
page.  To expedite a response to comments, be sure to mention your interest in
the soaring forecast.

DEFINITIONS:

CAPE (Convective Available Potential Energy) - An integrated measure of the
     energy available for convective development, also known as the positive
     area on a thermodynamic diagram.  Units are Joules per kilogram.  Larger
     values are indicative of greater instability and the possibility of
     stronger convective activity, including thunderstorms.  Values around or
     greater than 1000 suggest the possibility of severe weather should
     convective activity develop.

CIN (Convective Inhibition) - An integrated measure of the amount of energy
     needed to initiate convective activity, also known as the negative area on
     a thermodynamic diagram.  Units are Joules per kilogram.  The more negative
     this number, the more energy is required to initiate convection.  This
     inhibitive energy can be overcome through surface heating, cooling aloft,
     lifting mechanisms (orographic, frontal, gravity waves, etc.)

Convective Condensation Level - The height to which an air parcel possessing the
     average saturation mixing ratio in the lowest 4000 feet of the airmass,
     if heated sufficiently from below, will rise dry adiabatically until it
     just becomes saturated.  It estimates the base of cumulus clouds that are
     produced by surface heating only.

Convection Temperature (ConvectionT) - The surface temperature required to make
     the airmass dry adiabatic up to the given level.  It can be considered a
     "trigger temperature" for that level.

Freezing Level - The height where the temperature is zero degrees Celsius.

Height of Stable Layer - The height (between 12,000 and 18,000 feet above
     mean sea level) where the smallest lapse rate exists.  The location and
     existence of this feature is important in the generation of mountain
     waves.

K Index - A measure of stability which combines the temperature difference
     between approximately 5,000 and 18,000 feet above the surface, the amount
     of moisture at approximately 5,000 feet above the surface, and a measure
     of the dryness at approximately 10,000 feet above the surface.  Larger
     positive numbers indicate more instability and a greater likelihood of
     thunderstorm development.  One interpretation of K index values regarding
     soaring in the western United States is given in WMO Technical Note 158
     and is reproduced in the following table:

          below -10    no or weak thermals
           -10 to 5    dry thermals or 1/8 cumulus with moderate thermals
            5 to 15    good soaring conditions
           15 to 20    good soaring conditions with occasional showers
           20 to 30    excellent soaring conditions, but increasing
                       probability of showers and thunderstorms
           above 30    more than 60 percent probability of thunderstorms

Lapse Rate - The change with height of the temperature. Negative values indicate
     inversions.

Lifted Condensation Level - The height to which an air parcel possessing the
     average dew point in the lowest 4000 feet of the airmass and the forecast
     maximum temperature must be lifted dry adiabatically to attain saturation.

Lifted Index (LI) - The difference between the environmental temperature at a
     level approximately 18,000 feet above the surface and the temperature of
     an air parcel lifted dry adiabatically from the surface to its lifted
     condensation level and then pseudoadiabatically thereafter to this same
     level.  The parcel`s initial temperature is the forecast maximum
     temperature and its dew point is the average dew point in the lowest 4000
     feet of the airmass.  Negative values are indicative of instability with
     positive values showing stable conditions.

Lift Rate - An experimental estimate of the strength of thermals.  It is
     computed the same way as the maximum rate of lift but uses the actual
     level rather than the maximum height of thermals in the calculation.
     Also, none of the empirical adjustments based on cloudiness and K-index
     are applied to these calculations.

Maximum Height of Thermals - The height where the dry adiabat through the
     forecast maximum temperature intersects the environmental temperature.

Maximum Rate of Lift - An estimate of the maximum strength of thermals.  It
     is computed from an empirical formula which combines the expected maximum
     height of thermals with the difference in the environmental temperatures
     between the maximum height of thermals and the temperature 4,000 feet
     above the ground.  After this computation, further empirical adjustments
     are made based on the value of the K-index and the amount and opacity of
     middle and high level cloudiness expected between the time of trigger
     temperature and the time of overdevelopment.

Middle/High Clouds - The amount and opacity of middle (altostratus, altocumulus)
     or high (cirrus, cirrostratus, cirrocumulus) clouds.  Broken means that
     between 60% and 90% of the sky is covered by the cloud, with overcast
     conditions occurring when more than 90% of the sky is covered by the cloud.
     Thin implies that the clouds are predominantly transparent, meaning that
     some sunlight is reaching the ground, in contrast to opaque which suggests
     that little sunlight is reaching the ground.

Potential Height of Wave - The minimum of the following two heights:
     1. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind direction changes by 30 degrees or more
     2. Level above the height of stable layer (or 14,000 feet if none exists)
        where the wind speed no longer increases with height

PVA/NVA - Positive vorticity advection (PVA)/negative vorticity advection (NVA)
     on the 500 millibar isobaric surface (approximately 18,000 feet above mean
     sea level).  Weak PVA has been shown to assist in mountain wave soaring.

Soaring Window - The time between the time the trigger temperature is reached
                 and the time of overdevelopment.

Thermal Index - The difference between the environmental temperature and the
     temperature at a particular level determined by following the dry adiabat
     through the forecast maximum temperature up to that level.  Negative values
     are indicative of thermal lift.

Thermal Soaring Index - An adjective rating (for sailplanes) based on the
     computed maximum rate of lift, and the wind speed and middle and high
     cloud cover expected during the soaring window (the time of the trigger
     temperature and the time of overdevelopment) according to the following:

                 Maximum rate of lift        Adjective Rating
                      >= 800 fpm                 Excellent
                 >= 400 and < 800 fpm              Good
                 >= 200 and < 400 fpm              Fair
                       < 200 fpm                   Poor

Time of Overdevelopment - The time one or more of the following phenomena,
     which essentially shut off thermal lift, is expected to occur:
     1. formation of broken to overcast convective cloud cover
     2. formation of scattered to numerous downbursts
     3. initiation of widespread precipitation

Time of Trigger Temperature - The time the surface temperature is expected to
     reach the trigger temperature.

Trigger Temperature - The surface temperature required to make the first 4000
     feet of the atmosphere dry adiabatic.

Wave Soaring Index - An empirical, adjective rating (for sailplanes) which
     attempts to combine a variety of phenomena important in mountain wave
     soaring into a single index number.  Objective points are assigned to
     these phenomena: wind speed and direction at 14,000 ft MSL, the static
     stability in the 12,000-18,000 ft MSL layer, the wind speed gradient above
     the stable layer, jet stream location and frontal and upper trough
     movements.

042613


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