Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 230143
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1943 MDT Tuesday, July 22, 2014

This forecast is for Wednesday, July 23, 2014:

If the trigger temperature of 87.4 F/30.8 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1009 ft/min (5.1 m/s)
   Maximum height of thermals.................. 17258 ft MSL (11971 ft AGL)

Forecast maximum temperature................... 95.0 F/35.5 C
Time of trigger temperature.................... 1045 MDT
Time of overdevelopment........................ 1600 MDT
Middle/high clouds during soaring window....... Overcast thin high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 11057 ft MSL (5770 ft AGL)
Thermal soaring outlook for Thursday 07/24..... 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)................ Neither
Potential height of wave....................... 14413 ft MSL (9126 ft AGL)
Wave soaring outlook for Thursday 07/24........ Poor

Remarks... Scattered afternoon thunderstorms

Sunrise/Sunset.................... 05:50:32 / 20:21:36 MDT
Total possible sunshine........... 14 hr 31 min 4 sec (871 min 4 sec)
Altitude of sun at 13:05:55 MDT... 70.17 degrees

Upper air data from numerical model forecast valid on 07/23/2014 at 0600 MDT

Freezing level.................. 16934 ft MSL (11647 ft AGL)
Convective condensation level... 16104 ft MSL (10817 ft AGL)
Lifted condensation level....... 16360 ft MSL (11073 ft AGL)
Lifted index.................... -4.8
K index......................... +22.6

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  -66.7 -88.1   290   23   12   2.0   1.1      M     M       M      M    M
 45000  -60.8 -77.4   290   43   22   6.8   3.7      M     M       M      M    M
 40000  -50.5 -58.9   290   55   28   6.9   3.8      M     M       M      M    M
 38000  -46.4 -51.5   290   48   25   6.9   3.8      M     M       M      M    M
 36000  -42.2 -44.0   290   42   22   6.9   3.8      M     M       M      M    M
 34000  -37.5 -35.5   285   33   17   7.0   3.8      M     M       M      M    M
 32000  -33.4 -28.1   280   26   13   7.1   3.9   48.6 119.6    10.2      M    M
 30000  -29.2 -20.6   275   23   12   6.9   3.8   46.2 115.1     8.5      M    M
 29000  -27.2 -17.0   270   21   11   6.9   3.8   45.1 113.3     7.8      M    M
 28000  -25.1 -13.2   270   19   10   7.0   3.8   44.1 111.3     7.0      M    M
 27000  -23.0  -9.4   275   17    9   7.0   3.8   42.9 109.3     6.2      M    M
 26000  -20.9  -5.6   280   16    8   7.0   3.8   41.9 107.5     5.5      M    M
 25000  -18.8  -1.8   285   14    7   8.3   4.5   41.1 106.0     4.9      M    M
 24000  -16.3   2.7   290   11    6   8.2   4.5   40.4 104.8     4.4      M    M
 23000  -13.8   7.2   300    8    4   8.2   4.5   39.9 103.8     4.0      M    M
 22000  -11.4  11.5   310    6    3   7.1   3.9   39.3 102.7     3.5      M    M
 21000   -9.3  15.3   320    5    3   7.2   4.0   38.3 101.0     2.7      M    M
 20000   -7.1  19.2   335    4    2   7.2   4.0   37.5  99.4     2.0      M    M
 19500   -6.0  21.2   340    4    2   8.0   4.4   37.1  98.8     1.7      M    M
 19000   -4.8  23.4   335    5    2   8.4   4.6   36.9  98.3     1.5      M    M
 18500   -3.6  25.5   330    5    3   8.5   4.7   36.6  97.9     1.2      M    M
 18000   -2.5  27.5   325    5    3   6.8   3.7   36.3  97.3     0.8      M    M
 17500   -1.5  29.3   320    4    2   7.1   3.9   35.8  96.4     0.3      M    M
 17000    0.1  32.2   305    3    2   9.2   5.0   35.3  95.6    -0.2   1070  5.4
 16500    1.5  34.7   295    3    1   9.0   5.0   35.2  95.3    -0.4   1016  5.2
 16000    2.8  37.0   290    3    1   9.3   5.1   35.1  95.2    -0.5    961  4.9
 15500    4.2  39.6   275    3    1   9.3   5.1   35.0  95.0    -0.6    904  4.6
 15000    5.6  42.1   260    2    1   9.0   5.0   35.0  94.9    -0.6    848  4.3
 14500    6.8  44.2   240    4    2   8.7   4.8   34.8  94.6    -0.8    795  4.0
 14000    8.1  46.6   230    5    3   8.5   4.6   34.6  94.3    -1.0    742  3.8
 13500    9.2  48.6   220    6    3   7.1   3.9   34.2  93.6    -1.5    696  3.5
 13000   10.1  50.2   210    7    4   7.2   4.0   33.8  92.9    -1.9    651  3.3
 12500   11.3  52.3   210    8    4   8.6   4.7   33.5  92.4    -2.3    603  3.1
 12000   12.5  54.5   205    9    5   8.5   4.7   33.3  92.0    -2.6    552  2.8
 11500   13.7  56.7   205   10    5   8.7   4.8   33.2  91.7    -2.8    501  2.5
 11000   14.9  58.8   205   12    6   9.0   4.9   33.0  91.4    -3.0    448  2.3
 10500   16.0  60.8   205   13    7   5.3   2.9   32.6  90.7    -3.4    400  2.0
 10250   16.5  61.7   205   14    7   8.1   4.4   32.3  90.2    -3.7    379  1.9
 10000   17.2  63.0   210   15    7  10.7   5.9   32.4  90.2    -3.7    350  1.8
  9750   17.9  64.2   210   15    8   8.8   4.8   32.4  90.3    -3.7    321  1.6
  9500   18.5  65.3   210   16    8   7.3   4.0   32.2  90.0    -3.9    297  1.5
  9250   19.0  66.2   210   16    8   7.7   4.2   32.0  89.7    -4.1    273  1.4
  9000   19.6  67.3   205   17    9   9.6   5.3   31.9  89.5    -4.2    248  1.3
  8750   20.3  68.5   205   18    9   8.6   4.7   31.9  89.5    -4.3    220  1.1
  8500   20.8  69.4   205   17    9   6.8   3.7   31.7  89.1    -4.5    198  1.0
  8250   21.3  70.3   200   16    8   6.8   3.8   31.5  88.8    -4.8    175  0.9
  8000   21.8  71.2   200   16    8   8.6   4.7   31.3  88.4    -5.0    152  0.8
  7750   22.5  72.5   195   15    8   7.0   3.9   31.3  88.3    -5.1    125  0.6
  7500   22.8  73.0   200   14    7   3.7   2.0   30.9  87.6    -5.5    108  0.5
  7250   23.2  73.8   205   13    7   5.6   3.1   30.5  86.8    -5.9     90  0.5
  7000   23.5  74.3   210   12    6   1.1   0.6   30.1  86.1    -6.3     73  0.4
  6750   23.3  73.9   215   10    5  -3.9  -2.1   29.1  84.5    -7.3     72  0.4
  6500   23.0  73.4   225    8    4  -3.6  -2.0   28.1  82.6    -8.3     74  0.4
  6250   22.7  72.9   245    6    3  -3.0  -1.6   27.1  80.8    -9.4     75  0.4
  6000   22.4  72.3   270    6    3  -5.6  -3.1   26.1  79.0   -10.4     77  0.4
  5750   21.7  71.1   270    6    3 -11.4  -6.3   24.8  76.6   -11.9     91  0.5
  5500   20.6  69.1   255    4    2 -12.8  -7.0   23.1  73.6   -13.7    115  0.6

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

           07/23/2014 at 0900 MDT          |       07/23/2014 at 1200 MDT
                                           |
K index... +21.3  LI... -2.0               | K index... +23.8  LI... -3.6
CAPE... +422.5  CIN... -210.3              | CAPE... +860.6  CIN... -25.9
                                           |
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 -67.1 -88.8  290  22 11   2.4   1.3 | -67.2 -89.0  290  24 13   1.9   1.0
 45000 -61.0 -77.8  290  39 20   6.6   3.6 | -61.3 -78.3  290  41 21   6.9   3.8
 40000 -50.8 -59.4  290  50 26   7.3   4.0 | -50.9 -59.6  290  50 26   7.1   3.9
 38000 -46.4 -51.5  290  45 23   7.3   4.0 | -46.6 -51.9  290  43 22   7.1   3.9
 36000 -42.0 -43.6  290  40 20   7.3   4.0 | -42.3 -44.1  290  37 19   7.4   4.1
 34000 -37.1 -34.8  290  33 17   7.2   4.0 | -37.3 -35.1  285  32 17   7.5   4.1
 32000 -32.8 -27.0  290  28 14   6.7   3.7 | -32.8 -27.0  280  28 14   7.7   4.2
 30000 -29.0 -20.2  280  23 12   6.3   3.5 | -28.6 -19.5  275  22 11   7.1   3.9
 29000 -27.1 -16.8  270  21 11   6.4   3.5 | -26.4 -15.5  270  19 10   7.1   3.9
 28000 -25.2 -13.4  270  19 10   6.9   3.8 | -24.4 -11.9  265  17  9   6.7   3.7
 27000 -23.1  -9.6  265  17  9   7.0   3.8 | -22.4  -8.3  255  15  8   6.7   3.7
 26000 -21.0  -5.8  265  14  7   6.9   3.8 | -20.4  -4.7  245  14  7   6.8   3.7
 25000 -18.9  -2.0  265  12  6   7.8   4.3 | -18.4  -1.1  240  12  6   7.0   3.8
 24000 -16.5   2.3  270  10  5   7.7   4.2 | -16.2   2.8  245   9  5   7.0   3.8
 23000 -14.1   6.6  275   8  4   7.8   4.3 | -14.1   6.6  250   6  3   7.0   3.8
 22000 -11.8  10.8  285   7  4   7.3   4.0 | -11.9  10.6  270   4  2   7.5   4.1
 21000  -9.7  14.5  290   6  3   7.4   4.1 |  -9.8  14.4  275   3  2   7.5   4.1
 20000  -7.5  18.5  290   6  3   7.5   4.1 |  -7.6  18.3  290   3  1   7.6   4.2
 19500  -6.3  20.7  295   5  3   8.6   4.7 |  -6.5  20.3  295   3  1   8.2   4.5
 19000  -5.0  23.0  300   6  3   9.0   5.0 |  -5.3  22.5  295   3  1   8.3   4.6
 18500  -3.7  25.3  305   6  3   9.1   5.0 |  -4.1  24.6  295   3  1   8.4   4.6
 18000  -2.5  27.5  305   5  3   7.4   4.1 |  -2.8  27.0  290   2  1   8.1   4.5
 17500  -1.5  29.3  305   4  2   7.6   4.2 |  -1.6  29.1  245   1  0   8.1   4.5
 17000   0.3  32.5  295   2  1   8.6   4.7 |  -0.4  31.3  180   1  1   8.5   4.7
 16500   1.5  34.7  270   1  1   8.5   4.7 |   1.5  34.7  185   4  2   8.7   4.8
 16000   2.8  37.0  205   1  0   9.3   5.1 |   2.8  37.0  185   5  3   8.8   4.8
 15500   4.3  39.7  185   1  1   9.4   5.2 |   4.1  39.4  185   6  3   8.8   4.8
 15000   5.7  42.3  170   1  1   9.2   5.0 |   5.4  41.7  190   7  4   8.9   4.9
 14500   7.0  44.6  190   3  1   8.9   4.9 |   6.7  44.1  195   8  4   9.0   4.9
 14000   8.3  46.9  200   4  2   8.7   4.8 |   8.0  46.4  200   9  5   9.0   4.9
 13500   9.4  48.9  205   6  3   7.8   4.3 |   9.3  48.7  205  11  5   8.9   4.9
 13000  10.5  50.9  210   7  4   7.9   4.4 |  10.5  50.9  205  12  6   8.9   4.9
 12500  11.7  53.1  210   9  5   8.6   4.7 |  11.8  53.2  205  13  7   8.3   4.6
 12000  12.9  55.2  210  10  5   8.6   4.7 |  13.0  55.4  205  14  7   8.3   4.6
 11500  14.1  57.4  210  11  6   8.0   4.4 |  14.3  57.7  205  14  7   8.9   4.9
 11000  15.3  59.5  210  12  6   8.2   4.5 |  15.5  59.9  200  15  8   9.2   5.1
 10500  16.3  61.3  210  13  6   5.9   3.2 |  16.5  61.7  200  16  8   6.0   3.3
 10250  16.8  62.2  210  13  7   8.7   4.8 |  17.1  62.8  200  16  8   9.3   5.1
 10000  17.6  63.7  210  14  7  11.2   6.2 |  17.8  64.0  200  16  8  11.4   6.2
  9750  18.4  65.1  215  14  7   9.1   5.0 |  18.5  65.3  200  15  8   9.6   5.2
  9500  18.9  66.0  215  15  8   7.3   4.0 |  19.1  66.4  195  15  8   7.7   4.2
  9250  19.5  67.1  215  16  8   7.7   4.2 |  19.7  67.5  195  15  8   9.0   5.0
  9000  20.1  68.2  215  17  9   9.4   5.2 |  20.4  68.7  195  15  8  11.5   6.3
  8750  20.7  69.3  215  17  9   7.7   4.2 |  21.3  70.3  195  14  7  10.4   5.7
  8500  21.1  70.0  215  17  9   5.5   3.0 |  21.9  71.4  195  14  7   8.9   4.9
  8250  21.5  70.7  210  16  8   5.7   3.1 |  22.6  72.7  195  14  7   8.8   4.8
  8000  21.9  71.4  205  16  8   7.3   4.0 |  23.3  73.9  195  14  7  11.4   6.3
  7750  22.5  72.5  205  15  8   8.1   4.5 |  24.3  75.7  195  14  7  11.6   6.4
  7500  23.0  73.4  205  14  7   6.7   3.7 |  25.0  77.0  195  14  7   9.2   5.1
  7250  23.5  74.3  205  14  7   7.7   4.2 |  25.7  78.3  195  14  7   9.8   5.4
  7000  24.0  75.2  205  14  7   5.0   2.7 |  26.4  79.5  195  14  7  10.1   5.5
  6750  24.1  75.4  205  12  6  -0.7  -0.4 |  27.2  81.0  195  13  7  10.3   5.7
  6500  23.9  75.0  200   9  5  -1.3  -0.7 |  28.0  82.4  195  13  7  10.3   5.6
  6250  23.8  74.8  195   6  3  -3.5  -1.9 |  28.7  83.7  195  13  7   9.5   5.2
  6000  23.6  74.5  185   3  2   6.0   3.3 |  29.5  85.1  195  13  7  12.5   6.9
  5750  24.6  76.3  190   3  2  17.7   9.7 |  30.7  87.3  200  12  6  19.5  10.7
  5500  25.7  78.3  180   2  1   8.7   4.8 |  32.2  90.0  195  12  6  22.0  12.1

           07/23/2014 at 1500 MDT          |       07/23/2014 at 1800 MDT
                                           |
K index... +21.8  LI... -1.3               | K index... +22.0  LI... -1.0
CAPE... +267.7  CIN... -41.1               | CAPE... +119.5  CIN... -37.1
                                           |
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 -66.8 -88.2  290  27 14   1.5   0.8 | -67.0 -88.6  295  29 15   1.6   0.9
 45000 -61.1 -78.0  295  46 24   7.2   3.9 | -61.1 -78.0  300  47 24   7.4   4.1
 40000 -50.4 -58.7  290  53 27   7.0   3.9 | -50.0 -58.0  295  54 28   7.0   3.9
 38000 -46.2 -51.2  290  46 24   7.0   3.9 | -45.8 -50.4  295  47 24   7.0   3.9
 36000 -42.0 -43.6  290  39 20   7.3   4.0 | -41.5 -42.7  290  41 21   7.6   4.2
 34000 -37.0 -34.6  285  33 17   7.4   4.0 | -36.3 -33.3  290  36 18   7.7   4.2
 32000 -32.5 -26.5  285  28 14   8.2   4.5 | -31.7 -25.1  285  31 16   7.6   4.2
 30000 -28.1 -18.6  275  22 11   7.4   4.1 | -27.6 -17.7  285  24 12   6.9   3.8
 29000 -25.9 -14.6  270  19 10   7.4   4.1 | -25.6 -14.1  285  21 11   6.9   3.8
 28000 -23.8 -10.8  265  18  9   6.5   3.6 | -23.6 -10.5  285  18  9   6.7   3.7
 27000 -21.9  -7.4  255  16  8   6.5   3.6 | -21.6  -6.9  285  16  8   6.7   3.7
 26000 -20.0  -4.0  245  16  8   6.6   3.6 | -19.6  -3.3  290  14  7   6.8   3.7
 25000 -18.1  -0.6  235  15  8   6.0   3.3 | -17.6   0.3  290  13  7   6.9   3.8
 24000 -16.3   2.7  225  13  7   6.1   3.3 | -15.5   4.1  275  12  6   6.9   3.8
 23000 -14.4   6.1  215  10  5   6.1   3.3 | -13.5   7.7  260  13  7   6.9   3.8
 22000 -12.4   9.7  205   8  4   8.8   4.8 | -11.4  11.5  245  13  7   7.0   3.8
 21000  -9.9  14.2  200   7  3   8.5   4.7 |  -9.3  15.3  230  11  6   7.0   3.8
 20000  -7.3  18.9  195   5  2   8.5   4.7 |  -7.2  19.0  205   9  5   7.0   3.8
 19500  -6.1  21.0  185   4  2   8.1   4.5 |  -6.1  21.0  190   9  5   7.5   4.1
 19000  -4.9  23.2  175   3  2   8.0   4.4 |  -5.0  23.0  185   9  5   7.9   4.3
 18500  -3.7  25.3  165   3  2   8.0   4.4 |  -3.8  25.2  180   9  5   7.8   4.3
 18000  -2.5  27.5  160   4  2   8.3   4.6 |  -2.5  27.5  180   9  5   9.1   5.0
 17500  -1.3  29.7  155   5  3   8.3   4.5 |  -1.2  29.8  185  10  5   9.0   4.9
 17000  -0.0  32.0  160   6  3   8.6   4.7 |   0.7  33.3  195  12  6   8.7   4.8
 16500   1.9  35.4  170   8  4   8.7   4.8 |   2.0  35.6  195  12  6   8.8   4.8
 16000   3.2  37.8  180  10  5   8.6   4.7 |   3.3  37.9  200  13  7   8.6   4.7
 15500   4.4  39.9  185  11  6   8.6   4.7 |   4.5  40.1  205  14  7   8.6   4.7
 15000   5.7  42.3  190  13  7   8.4   4.6 |   5.8  42.4  210  15  7   8.4   4.6
 14500   6.8  44.2  195  13  7   8.1   4.4 |   6.9  44.4  210  15  7   8.0   4.4
 14000   8.0  46.4  200  14  7   8.1   4.5 |   8.1  46.6  210  14  7   8.1   4.4
 13500   9.2  48.6  205  14  7   8.3   4.5 |   9.3  48.7  210  14  7   8.9   4.9
 13000  10.3  50.5  210  14  7   8.3   4.5 |  10.6  51.1  210  14  7   8.9   4.9
 12500  11.6  52.9  215  15  8   8.9   4.9 |  11.9  53.4  210  14  7   8.9   4.9
 12000  12.8  55.0  215  15  8   8.9   4.9 |  13.2  55.8  210  14  7   8.9   4.9
 11500  14.1  57.4  215  15  8   9.4   5.2 |  14.5  58.1  210  13  7   9.4   5.1
 11000  15.5  59.9  215  15  8  10.1   5.5 |  15.9  60.6  210  13  7   9.9   5.4
 10500  16.5  61.7  215  15  8   3.7   2.0 |  16.9  62.4  210  13  7   4.9   2.7
 10250  17.0  62.6  215  15  8  10.5   5.8 |  17.5  63.5  210  13  7   9.7   5.3
 10000  18.0  64.4  215  15  8  14.6   8.0 |  18.3  64.9  210  13  7  12.7   7.0
  9750  19.0  66.2  215  16  8  11.1   6.1 |  19.2  66.6  210  13  7  10.7   5.9
  9500  19.6  67.3  215  16  8   7.5   4.1 |  19.9  67.8  210  13  7   7.8   4.3
  9250  20.2  68.4  215  16  8   9.0   4.9 |  20.5  68.9  210  12  6   8.9   4.9
  9000  20.9  69.6  215  15  8  11.9   6.6 |  21.3  70.3  210  12  6  12.0   6.6
  8750  21.8  71.2  215  15  8  11.0   6.0 |  22.2  72.0  210  12  6  11.2   6.1
  8500  22.6  72.7  215  15  8   9.5   5.2 |  23.0  73.4  210  12  6   9.6   5.3
  8250  23.3  73.9  215  15  8   9.6   5.3 |  23.7  74.7  215  12  6   9.3   5.1
  8000  24.0  75.2  215  15  8  10.4   5.7 |  24.4  75.9  215  12  6  10.8   5.9
  7750  24.8  76.6  215  15  8  10.5   5.8 |  25.2  77.4  215  12  6  10.8   5.9
  7500  25.6  78.1  215  15  8   9.8   5.4 |  26.0  78.8  215  12  6   9.4   5.2
  7250  26.3  79.3  215  15  8  10.0   5.5 |  26.7  80.1  215  12  6   9.5   5.2
  7000  27.1  80.8  215  15  8   9.9   5.4 |  27.4  81.3  215  12  6  10.1   5.6
  6750  27.8  82.0  220  15  8  10.1   5.6 |  28.2  82.8  215  12  6  10.5   5.8
  6500  28.6  83.5  220  15  7  10.5   5.8 |  28.9  84.0  215  12  6  10.1   5.5
  6250  29.3  84.7  220  14  7   9.9   5.4 |  29.7  85.5  215  11  6  10.2   5.6
  6000  30.1  86.2  220  14  7  12.1   6.6 |  30.4  86.7  215  11  6  10.1   5.6
  5750  31.2  88.2  220  14  7  17.2   9.4 |  31.3  88.3  215  11  6  13.2   7.2
  5500  32.5  90.5  220  13  7  19.3  10.6 |  32.5  90.5  215  10  5  18.3  10.0
________________________________________________________________________________

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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