Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 210114
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1914 MDT Thursday, August 20, 2015

This forecast is for Friday, August 21, 2015:

If the trigger temperature of 81.6 F/27.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1390 ft/min (7.1 m/s)
   Maximum height of thermals.................. 19817 ft MSL (14510 ft AGL)

Forecast maximum temperature................... 91.0 F/33.2 C
Time of trigger temperature.................... 1100 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................. 14654 ft MSL (9348 ft AGL)
Thermal soaring outlook for Saturday 08/22..... Poor

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....................... 46054 ft MSL (40747 ft AGL)
Wave soaring outlook for Saturday 08/22........ Poor

Remarks...

Sunrise/Sunset.................... 06:16:58 / 19:48:52 MDT
Total possible sunshine........... 13 hr 31 min 53 sec (811 min 53 sec)
Altitude of sun at 13:02:32 MDT... 62.25 degrees

Upper air data from numerical model forecast valid on 08/21/2015 at 0600 MDT

Freezing level.................. 15318 ft MSL (10011 ft AGL)
Convective condensation level... 18359 ft MSL (13052 ft AGL)
Lifted condensation level....... 18906 ft MSL (13600 ft AGL)
Lifted index.................... -2.8
K index......................... +5.2

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  -59.2 -74.6   305   26   13   2.0   1.1      M     M       M      M    M
 45000  -56.3 -69.3   305   34   18   1.6   0.9      M     M       M      M    M
 40000  -53.7 -64.7   295   37   19   3.8   2.1      M     M       M      M    M
 38000  -51.3 -60.3   295   32   16   4.1   2.2      M     M       M      M    M
 36000  -48.8 -55.8   290   26   13   4.1   2.2      M     M       M      M    M
 34000  -45.2 -49.4   290   23   12   7.1   3.9      M     M       M      M    M
 32000  -41.0 -41.8   285   22   11   7.1   3.9      M     M       M      M    M
 30000  -36.5 -33.7   285   21   11   7.7   4.2   38.7 101.7     4.5      M    M
 29000  -34.2 -29.6   285   21   11   7.7   4.2   37.9 100.3     4.0      M    M
 28000  -31.3 -24.3   285   20   10   8.0   4.4   37.1  98.8     3.4      M    M
 27000  -28.7 -19.7   290   20   10   8.7   4.8   36.6  97.8     3.0      M    M
 26000  -26.1 -15.0   290   20   10   8.7   4.8   36.2  97.1     2.7      M    M
 25000  -23.5 -10.3   295   20   10   8.8   4.8   35.9  96.6     2.5      M    M
 24000  -21.0  -5.8   300   21   11   8.2   4.5   35.3  95.6     2.1      M    M
 23000  -18.6  -1.5   300   21   11   8.2   4.5   34.7  94.5     1.6      M    M
 22000  -16.1   3.0   300   22   11   8.3   4.5   34.3  93.7     1.2      M    M
 21000  -13.7   7.3   300   23   12   7.9   4.4   33.6  92.5     0.7      M    M
 20000  -11.4  11.5   300   23   12   7.9   4.4   33.0  91.3     0.1      M    M
 19500  -10.2  13.6   300   24   12   8.0   4.4   32.7  90.8    -0.1   1362  6.9
 19000   -9.0  15.8   300   24   12   7.6   4.2   32.4  90.3    -0.4   1312  6.7
 18500   -7.9  17.8   300   23   12   7.5   4.1   32.0  89.6    -0.8   1264  6.4
 18000   -6.8  19.8   295   23   12   7.5   4.1   31.6  88.9    -1.1   1216  6.2
 17500   -5.6  21.9   295   23   12   8.2   4.5   31.3  88.3    -1.4   1167  5.9
 17000   -4.4  24.1   295   22   11   8.2   4.5   31.0  87.8    -1.7   1116  5.7
 16500   -3.2  26.2   295   21   11   8.3   4.5   30.8  87.4    -1.9   1064  5.4
 16000   -2.0  28.4   295   21   11   8.3   4.5   30.5  86.9    -2.2   1013  5.1
 15500   -0.7  30.7   290   20   10   8.2   4.5   30.3  86.5    -2.4    961  4.9
 15000    1.0  33.8   290   20   10   7.9   4.4   29.8  85.7    -2.9    886  4.5
 14500    2.2  36.0   290   19   10   8.2   4.5   29.5  85.2    -3.2    837  4.3
 14000    3.4  38.1   285   19   10   8.4   4.6   29.3  84.7    -3.4    785  4.0
 13500    4.6  40.3   285   18    9   8.4   4.6   29.1  84.4    -3.7    734  3.7
 13000    5.8  42.4   285   17    9   8.1   4.5   28.8  83.9    -4.0    684  3.5
 12500    7.0  44.6   280   15    8   8.3   4.6   28.6  83.4    -4.3    634  3.2
 12000    8.3  46.9   280   14    7   9.5   5.2   28.5  83.2    -4.5    581  2.9
 11500    9.6  49.3   275   13    7   9.5   5.2   28.4  83.2    -4.6    525  2.7
 11000   10.9  51.6   275   12    6   8.2   4.5   28.2  82.8    -4.8    473  2.4
 10500   12.1  53.8   275   11    6  12.1   6.6   28.0  82.4    -5.1    423  2.1
 10250   13.1  55.6   275   10    5  12.9   7.1   28.4  83.1    -4.8    383  1.9
 10000   13.8  56.8   275   10    5   8.5   4.7   28.3  83.0    -4.8    355  1.8
  9750   14.5  58.1   275   10    5   9.7   5.3   28.3  83.0    -4.9    327  1.7
  9500   15.2  59.4   275   10    5   9.3   5.1   28.3  82.9    -4.9    298  1.5
  9250   15.9  60.6   275   10    5   8.4   4.6   28.2  82.8    -5.0    271  1.4
  9000   16.5  61.7   275   10    5   8.8   4.8   28.1  82.6    -5.1    246  1.2
  8750   17.2  63.0   275   10    5   9.7   5.3   28.1  82.6    -5.2    217  1.1
  8500   17.9  64.2   275   10    5   9.3   5.1   28.1  82.6    -5.2    189  1.0
  8250   18.6  65.5   275   10    5   8.8   4.8   28.0  82.5    -5.3    162  0.8
  8000   19.2  66.6   275   10    5   8.2   4.5   27.9  82.3    -5.4    135  0.7
  7750   19.8  67.6   275   10    5   7.9   4.3   27.8  82.1    -5.6    110  0.6
  7500   20.4  68.7   275    9    5   7.9   4.4   27.7  81.8    -5.7     86  0.4
  7250   20.9  69.6   280    9    5   8.4   4.6   27.5  81.6    -5.9     61  0.3
  7000   21.5  70.7   280    9    5   7.5   4.1   27.4  81.4    -6.1     36  0.2
  6750   22.0  71.6   280    9    5   7.9   4.3   27.2  81.0    -6.3     13  0.1
  6500   22.5  72.5   280    9    5   0.6   0.3   26.9  80.5    -6.6      M    M
  6250   22.1  71.8   280    9    4  -7.3  -4.0   25.8  78.5    -7.7      M    M
  6000   21.6  70.9   275    9    4  -4.1  -2.2   24.7  76.4    -9.0      4  0.0
  5750   21.1  70.0   270    9    5 -10.2  -5.6   23.5  74.4   -10.1     10  0.1
  5500   19.3  66.7   260    9    4 -39.7 -21.8   21.1  70.0   -12.7     57  0.3

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

           08/21/2015 at 0900 MDT          |       08/21/2015 at 1200 MDT
                                           |
K index... -8.3  LI... +2.2                | K index... +9.1  LI... +2.1
CAPE... 0.0  CIN... -0.5                   | CAPE... +3.5  CIN... -88.8
                                           |
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 -59.8 -75.6  295  18  9   2.2   1.2 | -60.2 -76.4  280  21 11   1.9   1.0
 45000 -56.5 -69.7  305  24 12   2.5   1.4 | -57.2 -71.0  295  25 13   2.5   1.4
 40000 -52.5 -62.5  310  32 16   3.0   1.6 | -53.2 -63.8  315  29 15   4.3   2.3
 38000 -50.7 -59.3  305  31 16   3.0   1.6 | -50.7 -59.3  315  28 14   4.1   2.3
 36000 -48.9 -56.0  300  29 15   3.0   1.7 | -48.2 -54.8  315  28 14   4.2   2.3
 34000 -45.3 -49.5  300  28 14   7.5   4.1 | -44.5 -48.1  315  27 14   7.3   4.0
 32000 -40.8 -41.4  295  26 14   7.5   4.1 | -40.1 -40.2  310  27 14   7.3   4.0
 30000 -36.4 -33.5  290  25 13   7.2   4.0 | -35.8 -32.4  300  27 14   7.0   3.8
 29000 -34.2 -29.6  290  25 13   7.2   4.0 | -33.8 -28.8  300  26 14   7.0   3.8
 28000 -31.5 -24.7  285  24 12   7.7   4.2 | -31.2 -24.2  295  26 14   7.5   4.1
 27000 -29.0 -20.2  285  24 12   8.8   4.8 | -28.7 -19.7  290  26 14   8.4   4.6
 26000 -26.3 -15.3  285  23 12   8.8   4.8 | -26.1 -15.0  290  26 14   8.4   4.6
 25000 -23.7 -10.7  285  23 12   8.8   4.8 | -23.6 -10.5  285  26 14   8.4   4.6
 24000 -21.2  -6.2  290  22 12   8.3   4.6 | -21.0  -5.8  285  26 13   8.8   4.8
 23000 -18.7  -1.7  290  22 11   8.3   4.6 | -18.4  -1.1  285  25 13   8.8   4.8
 22000 -16.2   2.8  290  22 11   8.3   4.6 | -15.7   3.7  285  25 13   8.8   4.8
 21000 -13.8   7.2  290  23 12   8.0   4.4 | -13.3   8.1  285  24 12   8.0   4.4
 20000 -11.4  11.5  295  23 12   8.0   4.4 | -10.9  12.4  290  24 12   8.0   4.4
 19500 -10.2  13.6  295  24 12   8.0   4.4 |  -9.7  14.5  290  23 12   8.1   4.4
 19000  -9.0  15.8  295  24 12   8.0   4.4 |  -8.5  16.7  295  23 12   7.7   4.2
 18500  -7.9  17.8  295  24 12   8.0   4.4 |  -7.4  18.7  295  23 12   7.6   4.2
 18000  -6.7  19.9  295  25 13   8.0   4.4 |  -6.2  20.8  300  24 12   7.6   4.2
 17500  -5.5  22.1  300  25 13   7.9   4.4 |  -5.1  22.8  300  25 13   7.8   4.3
 17000  -4.3  24.3  300  24 13   7.9   4.4 |  -3.9  25.0  305  26 13   7.8   4.3
 16500  -3.1  26.4  300  24 13   8.1   4.4 |  -2.8  27.0  305  27 14   8.1   4.4
 16000  -1.9  28.6  300  24 12   8.2   4.5 |  -1.6  29.1  305  28 14   8.2   4.5
 15500  -0.7  30.7  305  23 12   8.2   4.5 |  -0.4  31.3  310  29 15   8.3   4.6
 15000   1.2  34.2  305  22 12   8.4   4.6 |   1.4  34.5  305  30 15   8.4   4.6
 14500   2.4  36.3  305  22 11   8.2   4.5 |   2.7  36.9  305  30 15   8.7   4.8
 14000   3.6  38.5  305  21 11   8.1   4.4 |   4.0  39.2  305  29 15   8.9   4.9
 13500   4.8  40.6  305  21 11   8.1   4.4 |   5.3  41.5  305  28 15   9.0   4.9
 13000   6.0  42.8  305  20 10   8.1   4.5 |   6.6  43.9  305  27 14   9.1   5.0
 12500   7.2  45.0  305  20 10   8.2   4.5 |   8.0  46.4  305  25 13   9.1   5.0
 12000   8.4  47.1  305  19 10   8.6   4.7 |   9.3  48.7  305  24 12   8.9   4.9
 11500   9.7  49.5  300  19 10   8.6   4.7 |  10.6  51.1  305  23 12   8.9   4.9
 11000  11.0  51.8  300  18  9   8.5   4.7 |  11.8  53.2  305  21 11   7.7   4.2
 10500  12.3  54.1  295  18  9   5.3   2.9 |  12.9  55.2  305  19 10  10.3   5.6
 10250  12.5  54.5  295  18  9   6.5   3.5 |  13.7  56.7  310  18  9  10.8   5.9
 10000  13.3  55.9  295  18  9  11.7   6.4 |  14.3  57.7  310  17  9   7.9   4.3
  9750  14.1  57.4  290  18  9  10.3   5.7 |  14.9  58.8  310  16  8   8.7   4.8
  9500  14.8  58.6  290  17  9  10.5   5.8 |  15.6  60.1  310  15  8   8.4   4.6
  9250  15.6  60.1  290  17  9   9.0   5.0 |  16.2  61.2  315  14  7   8.2   4.5
  9000  16.2  61.2  290  17  9   8.8   4.8 |  16.8  62.2  310  12  6   8.5   4.7
  8750  16.9  62.4  285  17  9   9.4   5.1 |  17.4  63.3  310  11  6   8.7   4.8
  8500  17.5  63.5  285  16  8   9.2   5.1 |  18.1  64.6  305   9  5   8.8   4.9
  8250  18.2  64.8  285  16  8   9.7   5.3 |  18.8  65.8  300   7  4   9.8   5.4
  8000  18.9  66.0  285  16  8   9.1   5.0 |  19.5  67.1  290   6  3   9.9   5.4
  7750  19.5  67.1  285  16  8   8.3   4.6 |  20.2  68.4  285   6  3   9.4   5.2
  7500  20.1  68.2  285  16  8   8.5   4.6 |  21.0  69.8  280   6  3   9.8   5.4
  7250  20.7  69.3  285  16  8   8.5   4.7 |  21.7  71.1  280   5  3  10.4   5.7
  7000  21.3  70.3  285  15  8   8.1   4.5 |  22.5  72.5  280   5  3  10.3   5.6
  6750  21.9  71.4  285  15  8   9.2   5.1 |  23.2  73.8  280   5  3   9.1   5.0
  6500  22.5  72.5  285  14  7   4.1   2.3 |  23.9  75.0  275   5  3   9.9   5.4
  6250  22.4  72.3  280  12  6  -0.6  -0.4 |  24.7  76.5  275   5  3  11.4   6.2
  6000  22.4  72.3  275  11  6   0.3   0.2 |  25.5  77.9  275   5  2  10.4   5.7
  5750  22.2  72.0  270  10  5  -4.8  -2.6 |  26.3  79.3  275   5  2  12.0   6.6
  5500  21.5  70.7  255   7  4  -5.5  -3.0 |  27.5  81.5  275   5  2  19.8  10.9

           08/21/2015 at 1500 MDT          |       08/21/2015 at 1800 MDT
                                           |
K index... +18.6  LI... +1.2               | K index... +22.1  LI... -0.2
CAPE... +41.1  CIN... -70.7                | CAPE... +101.9  CIN... -21.4
                                           |
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 -60.8 -77.4  285  25 13   1.0   0.5 | -61.4 -78.5  290  31 16   1.0   0.6
 45000 -58.6 -73.5  300  37 19   3.2   1.7 | -59.1 -74.4  300  48 24   3.3   1.8
 40000 -53.5 -64.3  310  36 19   5.2   2.8 | -53.7 -64.7  305  46 23   5.1   2.8
 38000 -50.5 -58.9  315  34 17   5.0   2.7 | -50.8 -59.4  305  43 22   4.9   2.7
 36000 -47.5 -53.5  320  31 16   5.0   2.8 | -47.8 -54.0  305  41 21   5.0   2.8
 34000 -43.6 -46.5  320  30 16   7.1   3.9 | -43.5 -46.3  305  38 19   7.9   4.4
 32000 -39.4 -38.9  315  30 16   7.1   3.9 | -38.8 -37.8  305  35 18   8.9   4.4
 30000 -34.9 -30.8  305  29 15   7.6   4.2 | -34.0 -29.2  300  32 17   8.1   4.5
 29000 -32.1 -25.8  300  28 14   7.6   4.2 | -31.0 -23.8  295  31 16   8.1   4.5
 28000 -29.8 -21.6  295  27 14   7.6   4.2 | -28.6 -19.5  290  30 16   7.7   4.2
 27000 -27.5 -17.5  295  26 14   7.6   4.2 | -26.4 -15.5  290  29 15   7.2   4.0
 26000 -25.2 -13.4  295  26 13   7.6   4.2 | -24.3 -11.7  290  27 14   7.2   4.0
 25000 -23.0  -9.4  290  25 13   7.5   4.1 | -22.1  -7.8  290  25 13   7.2   4.0
 24000 -20.5  -4.9  290  25 13   8.6   4.7 | -19.9  -3.8  290  25 13   7.7   4.2
 23000 -17.9  -0.2  290  26 13   8.6   4.7 | -17.6   0.3  290  25 13   7.7   4.2
 22000 -15.3   4.5  290  26 13   8.6   4.7 | -15.3   4.5  290  24 13   7.7   4.2
 21000 -12.9   8.8  290  27 14   8.0   4.4 | -13.0   8.6  290  24 13   8.1   4.4
 20000 -10.5  13.1  290  29 15   8.0   4.4 | -10.6  12.9  290  25 13   8.1   4.4
 19500  -9.4  15.1  290  30 15   8.1   4.4 |  -9.4  15.1  290  25 13   8.1   4.4
 19000  -8.2  17.2  290  31 16   8.1   4.4 |  -8.2  17.2  290  24 13   8.7   4.8
 18500  -7.0  19.4  290  33 17   8.2   4.5 |  -6.9  19.6  285  24 12   8.9   4.9
 18000  -5.9  21.4  290  34 18   8.4   4.6 |  -5.6  21.9  285  24 12   8.8   4.8
 17500  -4.6  23.7  290  34 18   9.0   4.9 |  -4.4  24.1  285  23 12   8.5   4.7
 17000  -3.3  26.1  290  34 17   9.0   4.9 |  -3.1  26.4  280  22 11   8.5   4.7
 16500  -2.0  28.4  285  33 17   9.1   5.0 |  -1.8  28.8  280  22 11   9.5   5.2
 16000  -0.7  30.7  285  32 16   9.1   5.0 |  -0.4  31.3  280  21 11   9.6   5.3
 15500   0.6  33.1  285  30 15   9.1   5.0 |   1.7  35.1  280  20 10   9.5   5.2
 15000   2.7  36.9  285  28 14   9.2   5.0 |   3.1  37.6  280  20 10   9.5   5.2
 14500   4.0  39.2  285  26 13   9.0   5.0 |   4.5  40.1  275  19 10   9.6   5.3
 14000   5.3  41.5  285  25 13   9.0   4.9 |   6.0  42.8  275  18  9   9.7   5.3
 13500   6.7  44.1  285  23 12   9.1   5.0 |   7.4  45.3  275  17  9   9.6   5.3
 13000   8.1  46.6  285  22 11   9.2   5.1 |   8.8  47.8  275  16  8   9.4   5.2
 12500   9.4  48.9  290  20 10   9.1   5.0 |  10.2  50.4  275  15  8   9.4   5.1
 12000  10.8  51.4  290  18  9   8.7   4.8 |  11.6  52.9  270  13  7   9.2   5.1
 11500  12.1  53.8  290  16  8   8.7   4.8 |  13.0  55.4  265  11  6   9.2   5.1
 11000  13.2  55.8  285  13  7   6.8   3.8 |  14.2  57.6  255  10  5   7.4   4.1
 10500  14.2  57.6  280   9  5   9.4   5.1 |  15.3  59.5  245   8  4  10.2   5.6
 10250  15.0  59.0  275   7  4  10.4   5.7 |  16.2  61.2  235   8  4  11.2   6.1
 10000  15.7  60.3  265   6  3   7.9   4.4 |  16.9  62.4  225   8  4   8.3   4.6
  9750  16.3  61.3  255   5  3   8.7   4.8 |  17.6  63.7  220   8  4   9.1   5.0
  9500  16.9  62.4  240   4  2   8.2   4.5 |  18.2  64.8  215   8  4   8.7   4.8
  9250  17.5  63.5  225   4  2   8.3   4.6 |  18.9  66.0  210   8  4   7.8   4.3
  9000  18.2  64.8  225   4  2   9.8   5.4 |  19.4  66.9  205   8  4   8.0   4.4
  8750  18.9  66.0  225   4  2  10.5   5.8 |  20.1  68.2  200   8  4   8.8   4.8
  8500  19.7  67.5  220   4  2  10.3   5.6 |  20.7  69.3  200   8  4   8.6   4.7
  8250  20.5  68.9  220   4  2  10.0   5.5 |  21.4  70.5  195   8  4  10.4   5.7
  8000  21.2  70.2  220   4  2   9.7   5.3 |  22.1  71.8  195   8  4  10.4   5.7
  7750  21.9  71.4  220   4  2   9.6   5.3 |  22.8  73.0  195   8  4   9.1   5.0
  7500  22.6  72.7  220   4  2   9.9   5.4 |  23.5  74.3  195   8  4   9.5   5.2
  7250  23.4  74.1  215   4  2  10.4   5.7 |  24.2  75.6  195   7  4   9.7   5.3
  7000  24.2  75.6  215   4  2  10.4   5.7 |  25.0  77.0  195   7  4   9.7   5.3
  6750  24.9  76.8  215   4  2   9.7   5.3 |  25.7  78.3  195   7  4   9.3   5.1
  6500  25.7  78.3  220   4  2  10.2   5.6 |  26.4  79.5  200   7  4   9.9   5.4
  6250  26.5  79.7  220   4  2  11.0   6.0 |  27.2  81.0  200   7  4  11.0   6.1
  6000  27.3  81.1  220   4  2  10.7   5.9 |  28.0  82.4  200   7  3  11.2   6.1
  5750  28.1  82.6  220   4  2  11.0   6.0 |  28.8  83.8  200   7  3   9.5   5.2
  5500  29.0  84.2  215   4  2  17.7   9.7 |  29.4  84.9  200   6  3   9.8   5.4
________________________________________________________________________________

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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