Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 090043
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1843 MDT Tuesday, July 8, 2014

This forecast is for Wednesday, July 9, 2014:

If the trigger temperature of 86.3 F/30.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1488 ft/min (7.6 m/s)
   Maximum height of thermals.................. 18629 ft MSL (13342 ft AGL)

Forecast maximum temperature................... 93.0 F/34.3 C
Time of trigger temperature.................... 1100 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... None
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10291 ft MSL (5004 ft AGL)
Thermal soaring outlook for Thursday 07/10..... 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....................... 40642 ft MSL (35355 ft AGL)
Wave soaring outlook for Thursday 07/10........ Poor

Remarks... None

Sunrise/Sunset.................... 05:39:53 / 20:29:38 MDT
Total possible sunshine........... 14 hr 49 min 46 sec (889 min 46 sec)
Altitude of sun at 13:04:44 MDT... 72.49 degrees

Upper air data from numerical model forecast valid on 07/09/2014 at 0600 MDT

Freezing level.................. 16093 ft MSL (10806 ft AGL)
Convective condensation level... 15716 ft MSL (10429 ft AGL)
Lifted condensation level....... 16489 ft MSL (11201 ft AGL)
Lifted index.................... -5.4
K index......................... +25.1

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  -63.6 -82.5   345   30   15   2.4   1.3      M     M       M      M    M
 45000  -59.0 -74.2   330   40   21   4.6   2.5      M     M       M      M    M
 40000  -51.6 -60.9   310   45   23   5.3   2.9      M     M       M      M    M
 38000  -48.4 -55.1   305   46   24   5.3   2.9      M     M       M      M    M
 36000  -45.2 -49.4   305   48   25   5.4   3.0      M     M       M      M    M
 34000  -40.6 -41.1   305   41   21   8.0   4.4      M     M       M      M    M
 32000  -35.8 -32.4   310   34   18   7.9   4.3      M     M       M      M    M
 30000  -31.0 -23.8   315   30   15   8.0   4.4   44.9 112.8     8.4      M    M
 29000  -28.7 -19.7   310   28   14   8.0   4.4   44.2 111.6     8.0      M    M
 28000  -26.3 -15.3   310   26   14   6.8   3.7   43.7 110.6     7.6      M    M
 27000  -24.2 -11.6   310   24   12   5.6   3.1   41.6 106.8     6.1      M    M
 26000  -22.5  -8.5   305   22   11   5.7   3.1   40.0 104.1     4.9      M    M
 25000  -20.8  -5.4   305   20   10   6.8   3.7   38.7 101.6     3.9      M    M
 24000  -18.4  -1.1   305   19   10   8.0   4.4   37.9 100.2     3.3      M    M
 23000  -16.0   3.2   305   18    9   8.0   4.4   37.2  99.0     2.7      M    M
 22000  -13.7   7.3   305   17    9   7.9   4.3   36.7  98.0     2.3      M    M
 21000  -11.4  11.5   310   17    9   7.8   4.3   35.9  96.6     1.6      M    M
 20000   -9.1  15.6   315   16    8   7.9   4.3   35.2  95.4     1.0      M    M
 19500   -7.9  17.8   315   16    8   7.8   4.3   35.0  94.9     0.8      M    M
 19000   -6.9  19.6   320   15    8   7.0   3.9   34.5  94.2     0.4      M    M
 18500   -5.9  21.4   320   15    8   7.1   3.9   34.1  93.4    -0.1   1281  6.5
 18000   -4.8  23.4   320   15    8   7.9   4.4   33.7  92.6    -0.5   1235  6.3
 17500   -3.6  25.5   320   15    8   8.3   4.6   33.4  92.2    -0.8   1185  6.0
 17000   -2.5  27.5   320   14    7   8.4   4.6   33.2  91.7    -1.1   1134  5.8
 16500   -1.2  29.8   320   14    7   8.7   4.8   33.0  91.4    -1.3   1083  5.5
 16000    0.0  32.0   320   14    7   8.7   4.8   32.8  91.0    -1.5   1031  5.2
 15500    1.3  34.3   320   14    7   9.4   5.2   32.7  90.8    -1.7    978  5.0
 15000    2.7  36.9   320   14    7   9.5   5.2   32.6  90.7    -1.8    922  4.7
 14500    4.1  39.4   315   14    7   9.6   5.3   32.6  90.7    -1.9    865  4.4
 14000    6.2  43.2   315   13    7   9.7   5.3   32.6  90.6    -2.0    779  4.0
 13500    7.6  45.7   315   12    6   9.5   5.2   32.5  90.6    -2.0    722  3.7
 13000    9.0  48.2   315   11    6   9.5   5.2   32.5  90.5    -2.1    665  3.4
 12500   10.4  50.7   315   11    6   9.4   5.2   32.5  90.4    -2.1    609  3.1
 12000   11.8  53.2   315   10    5   9.4   5.2   32.4  90.3    -2.2    553  2.8
 11500   13.2  55.8   315   10    5   9.0   4.9   32.4  90.3    -2.3    497  2.5
 11000   14.4  57.9   310   10    5   8.4   4.6   32.2  89.9    -2.5    443  2.3
 10500   15.7  60.3   310    9    5   5.1   2.8   32.0  89.6    -2.7    390  2.0
 10250   15.9  60.6   310    9    5   5.6   3.1   31.5  88.7    -3.2    376  1.9
 10000   16.6  61.9   305    9    4  10.3   5.6   31.5  88.6    -3.3    349  1.8
  9750   17.3  63.1   305    8    4   9.6   5.3   31.4  88.6    -3.3    321  1.6
  9500   18.0  64.4   300    8    4   7.7   4.2   31.4  88.6    -3.4    293  1.5
  9250   18.4  65.1   300    7    4   5.7   3.1   31.1  88.0    -3.7    273  1.4
  9000   18.9  66.0   295    7    4   7.1   3.9   30.9  87.6    -3.9    251  1.3
  8750   19.4  66.9   290    7    4   7.8   4.3   30.7  87.3    -4.2    229  1.2
  8500   19.9  67.8   285    7    4   5.5   3.0   30.5  86.9    -4.4    207  1.1
  8250   20.1  68.2   270    7    3   3.6   2.0   30.1  86.1    -4.9    192  1.0
  8000   20.3  68.5   255    7    3   3.7   2.0   29.6  85.3    -5.4    178  0.9
  7750   20.5  68.9   240    8    4   3.0   1.7   29.1  84.4    -6.0    164  0.8
  7500   20.8  69.4   230    8    4   5.3   2.9   28.7  83.6    -6.4    149  0.8
  7250   21.2  70.2   220    9    4   6.3   3.5   28.4  83.1    -6.8    129  0.7
  7000   21.7  71.1   215    9    5   7.0   3.9   28.1  82.6    -7.1    109  0.6
  6750   22.1  71.8   215    9    5   3.4   1.9   27.9  82.2    -7.4     88  0.4
  6500   22.0  71.6   215    9    4  -3.2  -1.8   27.1  80.8    -8.2     83  0.4
  6250   21.6  70.9   215    9    4  -8.1  -4.5   25.9  78.7    -9.4     90  0.5
  6000   21.1  70.0   215    9    5   3.8   2.1   24.8  76.7   -10.6     96  0.5
  5750   21.5  70.7   220   10    5  -6.0  -3.3   24.5  76.1   -11.0     77  0.4
  5500   19.1  66.4   210    8    4 -54.9 -30.1   21.5  70.7   -14.1    142  0.7

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

           07/09/2014 at 0900 MDT          |       07/09/2014 at 1200 MDT
                                           |
K index... +25.6  LI... -2.4               | K index... +22.5  LI... -2.6
CAPE... +566.4  CIN... -126.7              | CAPE... +576.2  CIN... -18.7
                                           |
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  350  30 15   2.7   1.5 | -64.1 -83.4  345  30 16   2.6   1.4
 45000 -58.8 -73.8  340  39 20   5.0   2.7 | -58.9 -74.0  335  39 20   5.4   3.0
 40000 -51.1 -60.0  320  41 21   4.5   2.5 | -50.5 -58.9  320  39 20   4.8   2.6
 38000 -48.4 -55.1  315  43 22   4.5   2.5 | -47.7 -53.9  315  41 21   4.8   2.6
 36000 -45.7 -50.3  305  46 24   4.5   2.5 | -44.8 -48.6  305  43 22   4.8   2.6
 34000 -41.0 -41.8  310  41 21   8.0   4.4 | -40.5 -40.9  305  42 22   7.5   4.1
 32000 -36.2 -33.2  310  36 19   7.9   4.3 | -35.9 -32.6  310  41 21   7.4   4.1
 30000 -31.1 -24.0  310  33 17   8.6   4.7 | -31.3 -24.3  310  37 19   7.8   4.3
 29000 -28.5 -19.3  310  31 16   8.6   4.7 | -28.4 -19.1  315  34 17   7.8   4.3
 28000 -25.5 -13.9  310  29 15   5.6   3.1 | -26.1 -15.0  315  31 16   6.7   3.7
 27000 -23.7 -10.7  310  27 14   6.0   3.3 | -24.1 -11.4  315  29 15   6.9   3.8
 26000 -21.9  -7.4  310  25 13   6.0   3.3 | -22.0  -7.6  315  27 14   6.9   3.8
 25000 -20.1  -4.2  310  23 12   6.4   3.5 | -19.9  -3.8  315  24 13   6.9   3.8
 24000 -18.1  -0.6  305  22 11   6.8   3.7 | -17.8  -0.0  315  23 12   6.9   3.8
 23000 -16.1   3.0  300  20 10   6.8   3.7 | -15.8   3.6  310  21 11   6.9   3.8
 22000 -14.1   6.6  295  19 10   7.5   4.1 | -13.7   7.3  305  19 10   7.4   4.0
 21000 -11.7  10.9  300  18  9   7.9   4.4 | -11.5  11.3  305  18  9   7.6   4.2
 20000  -9.4  15.1  300  18  9   8.0   4.4 |  -9.2  15.4  310  18  9   7.7   4.2
 19500  -8.2  17.2  300  17  9   8.0   4.4 |  -8.1  17.4  315  17  9   7.8   4.3
 19000  -7.2  19.0  305  17  9   7.4   4.1 |  -6.9  19.6  315  17  9   8.4   4.6
 18500  -6.1  21.0  310  17  9   7.5   4.1 |  -5.7  21.7  320  17  9   8.4   4.6
 18000  -5.0  23.0  310  17  9   8.1   4.4 |  -4.5  23.9  320  18  9   8.6   4.7
 17500  -3.9  25.0  315  17  9   8.3   4.6 |  -3.2  26.2  320  18  9   8.7   4.8
 17000  -2.7  27.1  315  17  9   8.5   4.7 |  -2.0  28.4  320  18  9   8.7   4.8
 16500  -1.4  29.5  315  17  9   9.4   5.2 |  -0.7  30.7  320  18  9   8.5   4.7
 16000  -0.0  32.0  315  17  9   9.4   5.1 |   0.5  32.9  320  18  9   8.5   4.7
 15500   1.3  34.3  320  16  8   9.7   5.3 |   1.8  35.2  320  17  9   9.0   5.0
 15000   2.8  37.0  320  15  8   9.7   5.3 |   3.1  37.6  320  17  9   9.1   5.0
 14500   4.9  40.8  320  14  7   9.2   5.0 |   5.1  41.2  320  16  8   9.5   5.2
 14000   6.2  43.2  320  13  7   9.3   5.1 |   6.5  43.7  320  15  8   9.5   5.2
 13500   7.6  45.7  325  13  7   9.2   5.1 |   7.9  46.2  320  14  7   9.3   5.1
 13000   9.0  48.2  325  13  7   9.2   5.1 |   9.2  48.6  320  14  7   9.2   5.1
 12500  10.4  50.7  325  13  7   9.2   5.1 |  10.6  51.1  320  14  7   9.3   5.1
 12000  11.7  53.1  320  13  7   9.2   5.1 |  12.0  53.6  320  13  7   9.3   5.1
 11500  13.1  55.6  320  13  7   9.0   4.9 |  13.3  55.9  325  13  7   9.3   5.1
 11000  14.4  57.9  320  13  7   8.6   4.7 |  14.7  58.5  325  13  7   9.0   5.0
 10500  15.7  60.3  315  13  7   5.4   3.0 |  16.1  61.0  320  13  7   6.0   3.3
 10250  16.0  60.8  315  13  7   6.4   3.5 |  16.3  61.3  320  13  7   6.5   3.6
 10000  16.8  62.2  310  13  7  11.1   6.1 |  17.1  62.8  320  13  7  10.9   6.0
  9750  17.5  63.5  310  13  7  10.7   5.8 |  17.8  64.0  320  13  7  10.2   5.6
  9500  18.3  64.9  305  13  7   7.7   4.2 |  18.5  65.3  320  13  7   8.6   4.7
  9250  18.7  65.7  300  12  6   5.7   3.1 |  19.0  66.2  315  12  6   7.7   4.2
  9000  19.2  66.6  295  12  6   8.7   4.8 |  19.6  67.3  310  10  5   9.6   5.3
  8750  19.9  67.8  290  11  6   9.1   5.0 |  20.3  68.5  305   9  5   9.5   5.2
  8500  20.5  68.9  285  11  6   7.8   4.3 |  21.0  69.8  300   8  4   9.8   5.4
  8250  21.0  69.8  280  10  5   6.8   3.7 |  21.7  71.1  300   8  4  10.0   5.5
  8000  21.5  70.7  275  10  5   7.0   3.8 |  22.4  72.3  295   8  4  10.0   5.5
  7750  22.0  71.6  275  11  5   6.8   3.7 |  23.2  73.8  295   8  4  10.1   5.6
  7500  22.5  72.5  270  11  6   7.0   3.8 |  23.9  75.0  295   8  4  10.3   5.7
  7250  23.0  73.4  275  11  6   6.8   3.8 |  24.7  76.5  295   8  4  10.5   5.8
  7000  23.5  74.3  275  11  6   7.5   4.1 |  25.5  77.9  295   8  4  10.3   5.6
  6750  24.0  75.2  280  12  6   6.1   3.4 |  26.3  79.3  295   8  4  10.2   5.6
  6500  24.2  75.6  280  10  5   2.3   1.2 |  27.0  80.6  295   7  4  10.4   5.7
  6250  24.3  75.7  275   9  4   3.0   1.6 |  27.8  82.0  295   7  4  11.1   6.1
  6000  24.3  75.7  265   7  3  -1.7  -1.0 |  28.6  83.5  295   7  4   8.8   4.8
  5750  23.9  75.0  235   4  2   3.8   2.1 |  29.3  84.7  290   7  4  14.5   8.0
  5500  25.0  77.0  230   4  2  27.8  15.2 |  31.0  87.8  290   7  4  30.8  16.9

           07/09/2014 at 1500 MDT          |       07/09/2014 at 1800 MDT
                                           |
K index... +27.0  LI... -1.4               | K index... +27.2  LI... -1.6
CAPE... +386.9  CIN... -16.0               | CAPE... +288.1  CIN... -4.8
                                           |
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 -64.4 -83.9  345  29 15   2.4   1.3 | -64.6 -84.3  350  30 16   2.3   1.3
 45000 -58.8 -73.8  335  38 20   5.8   3.2 | -59.0 -74.2  340  40 21   5.8   3.2
 40000 -50.1 -58.2  320  40 21   5.6   3.1 | -50.3 -58.5  325  44 23   5.9   3.2
 38000 -46.8 -52.2  310  41 21   5.6   3.1 | -46.8 -52.2  315  45 23   5.9   3.2
 36000 -43.5 -46.3  300  43 22   5.6   3.1 | -43.3 -45.9  305  48 25   6.0   3.3
 34000 -39.5 -39.1  300  42 22   6.6   3.6 | -39.2 -38.6  305  46 23   7.0   3.8
 32000 -35.6 -32.1  300  40 21   6.4   3.5 | -35.0 -31.0  310  43 22   6.8   3.7
 30000 -30.4 -22.7  305  37 19   7.9   4.3 | -30.0 -22.0  315  37 19   7.5   4.1
 29000 -28.0 -18.4  310  35 18   7.9   4.3 | -27.7 -17.9  315  34 18   7.5   4.1
 28000 -25.8 -14.4  310  34 17   6.6   3.6 | -25.5 -13.9  320  32 16   7.2   3.9
 27000 -23.7 -10.7  315  30 16   6.7   3.7 | -23.4 -10.1  320  29 15   7.2   4.0
 26000 -21.7  -7.1  315  27 14   6.8   3.7 | -21.2  -6.2  320  26 13   7.2   4.0
 25000 -19.7  -3.5  320  24 12   7.0   3.8 | -19.1  -2.4  325  23 12   7.2   3.9
 24000 -17.5   0.5  320  22 11   7.2   3.9 | -17.0   1.4  330  22 11   7.1   3.9
 23000 -15.4   4.3  315  20 11   7.2   3.9 | -14.9   5.2  330  21 11   7.1   3.9
 22000 -13.2   8.2  315  19 10   7.6   4.2 | -12.8   9.0  335  20 10   7.2   3.9
 21000 -10.9  12.4  320  18  9   8.0   4.4 | -10.7  12.7  340  20 10   7.2   4.0
 20000  -8.5  16.7  320  17  9   8.0   4.4 |  -8.6  16.5  345  19 10   7.3   4.0
 19500  -7.4  18.7  325  17  9   8.1   4.4 |  -7.5  18.5  350  19 10   7.3   4.0
 19000  -6.2  20.8  325  17  9   7.9   4.3 |  -6.4  20.5  350  18  9   7.7   4.2
 18500  -5.1  22.8  325  18  9   8.0   4.4 |  -5.3  22.5  350  17  9   7.7   4.2
 18000  -4.0  24.8  325  19 10   8.2   4.5 |  -4.2  24.4  355  16  8   7.7   4.2
 17500  -2.8  27.0  325  18  9   8.2   4.5 |  -3.1  26.4  355  15  8   7.7   4.2
 17000  -1.7  28.9  320  18  9   8.4   4.6 |  -1.9  28.6  360  14  7   7.7   4.2
 16500  -0.4  31.3  320  17  9   9.0   5.0 |  -0.8  30.6  360  12  6   8.3   4.5
 16000   0.9  33.6  320  16  8   9.0   4.9 |   0.4  32.7  360  10  5   8.2   4.5
 15500   2.2  36.0  325  16  8   9.2   5.0 |   1.6  34.9  360   9  5   9.6   5.3
 15000   4.2  39.6  325  15  7   9.3   5.1 |   3.8  38.8  360   8  4   9.8   5.4
 14500   5.6  42.1  325  14  7   8.9   4.9 |   5.3  41.5  360   7  4   9.7   5.3
 14000   6.9  44.4  325  12  6   9.0   4.9 |   6.7  44.1  355   7  4   9.8   5.4
 13500   8.2  46.8  325  11  6   9.0   5.0 |   8.2  46.8  355   7  3   9.8   5.4
 13000   9.6  49.3  325  10  5   9.0   5.0 |   9.6  49.3  350   6  3   9.9   5.4
 12500  10.9  51.6  325   8  4   8.9   4.9 |  11.1  52.0  350   5  3   9.5   5.2
 12000  12.1  53.8  325   7  4   8.8   4.8 |  12.4  54.3  345   5  3   9.3   5.1
 11500  13.4  56.1  320   5  3   9.3   5.1 |  13.8  56.8  340   4  2   9.5   5.2
 11000  14.9  58.8  315   5  3   9.6   5.3 |  15.3  59.5  335   4  2   9.5   5.2
 10500  16.4  61.5  315   5  2   5.8   3.2 |  16.7  62.1  335   4  2   5.9   3.2
 10250  16.6  61.9  315   5  2   6.9   3.8 |  17.0  62.6  330   4  2   7.0   3.8
 10000  17.5  63.5  315   5  2  12.7   7.0 |  17.9  64.2  330   4  2  12.6   6.9
  9750  18.4  65.1  315   5  2  11.8   6.5 |  18.7  65.7  325   4  2  11.9   6.5
  9500  19.2  66.6  315   5  2   9.7   5.3 |  19.5  67.1  325   4  2   9.3   5.1
  9250  19.8  67.6  315   5  2   8.8   4.8 |  20.1  68.2  320   4  2   7.9   4.4
  9000  20.6  69.1  315   5  2  11.2   6.1 |  20.8  69.4  320   4  2  10.6   5.8
  8750  21.4  70.5  310   5  2  11.2   6.2 |  21.6  70.9  320   5  2  10.4   5.7
  8500  22.3  72.1  310   5  2  10.4   5.7 |  22.4  72.3  315   5  2  10.6   5.8
  8250  23.0  73.4  310   5  2   9.5   5.2 |  23.2  73.8  315   5  2  10.7   5.9
  8000  23.7  74.7  310   5  2   9.8   5.4 |  23.9  75.0  310   5  2   9.7   5.3
  7750  24.5  76.1  310   5  2   9.8   5.4 |  24.6  76.3  310   5  2   8.8   4.8
  7500  25.2  77.4  310   5  2  10.1   5.6 |  25.3  77.5  310   5  2   9.9   5.4
  7250  26.0  78.8  305   5  2  10.6   5.8 |  26.1  79.0  310   5  3  10.7   5.9
  7000  26.8  80.2  305   5  3   9.9   5.4 |  26.9  80.4  310   5  3  10.3   5.6
  6750  27.5  81.5  305   5  2   9.6   5.2 |  27.6  81.7  310   5  3  10.0   5.5
  6500  28.2  82.8  305   5  2  10.6   5.8 |  28.4  83.1  305   5  3  10.2   5.6
  6250  29.0  84.2  305   5  2  11.9   6.5 |  29.1  84.4  305   5  3  10.8   5.9
  6000  29.9  85.8  305   5  2   9.5   5.2 |  29.9  85.8  305   5  3   9.5   5.2
  5750  30.6  87.1  305   5  2  14.1   7.7 |  30.6  87.1  305   5  3  11.4   6.2
  5500  32.2  90.0  305   5  2  29.0  15.9 |  31.8  89.2  305   5  3  18.9  10.4
________________________________________________________________________________

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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