Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 271248
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0648 MDT Thursday, August 27, 2015

This forecast is for Thursday, August 27, 2015:

If the trigger temperature of 81.9 F/27.7 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 947 ft/min (4.8 m/s)
   Maximum height of thermals.................. 15317 ft MSL (10032 ft AGL)

Forecast maximum temperature................... 85.0 F/29.9 C
Time of trigger temperature.................... 1300 MDT
Time of overdevelopment........................ 1400 MDT
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 7335 ft MSL (2050 ft AGL)
Thermal soaring outlook for Friday 08/28....... Fair

Wave Soaring Index............................. Fair
Wave Soaring Index trend (to 1800 MDT)......... No change
Height of stable layer (12-18K ft MSL)......... 16354 ft MSL (11069 ft AGL)
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39229 ft MSL (33944 ft AGL)
Wave soaring outlook for Friday 08/28.......... Poor

Remarks...

Sunrise/Sunset.................... 06:22:37 / 19:40:04 MDT
Total possible sunshine........... 13 hr 17 min 28 sec (797 min 28 sec)
Altitude of sun at 13:00:55 MDT... 60.20 degrees

Upper air data from rawinsonde observation taken on 08/27/2015 at 0600 MDT

Freezing level.................. 15086 ft MSL (9801 ft AGL)
Convective condensation level... 17604 ft MSL (12319 ft AGL)
Lifted condensation level....... 15813 ft MSL (10528 ft AGL)
Lifted index.................... +1.9
K index......................... +26.8

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  -65.2 -85.4   315   19   10   4.3   2.3   83.7 182.6    31.6      M    M
 45000  -61.6 -78.9   285   49   25   6.0   3.3   64.3 147.7    21.8      M    M
 40000  -52.1 -61.8   275   46   23   9.2   5.1   56.2 133.2    18.0      M    M
 38000  -47.6 -53.7   270   45   23   6.7   3.7   54.3 129.8    17.1      M    M
 36000  -43.5 -46.3   265   39   20   9.0   4.9   51.8 125.3    15.8      M    M
 34000  -38.2 -36.8   270   33   17   8.7   4.8   51.0 123.8    15.6      M    M
 32000  -33.2 -27.8   285   28   14   7.8   4.3   50.0 121.9    15.2      M    M
 30000  -28.1 -18.6   270   21   11   8.6   4.7   48.0 118.3    14.0      M    M
 29000  -25.5 -13.9   270   21   11   9.5   5.2   47.5 117.6    13.9      M    M
 28000  -22.7  -8.9   270   21   11   6.6   3.6   47.5 117.5    14.0      M    M
 27000  -21.1  -6.0   265   22   11   8.7   4.8   45.8 114.5    12.8      M    M
 26000  -18.7  -1.7   265   22   11   7.0   3.8   45.2 113.4    12.4      M    M
 25000  -17.3   0.9   265   22   11   0.1   0.0   43.5 110.3    11.1      M    M
 24000  -15.2   4.6   270   21   11   9.5   5.2   42.5 108.6    10.4      M    M
 23000  -14.0   6.8   270   21   11   3.1   1.7   40.5 104.9     8.8      M    M
 22000  -12.2  10.0   275   20   10   6.9   3.8   39.1 102.4     7.7      M    M
 21000  -10.2  13.6   280   19   10   6.9   3.8   38.1 100.6     6.9      M    M
 20000   -8.2  17.2   285   19   10   6.9   3.8   37.2  99.0     6.1      M    M
 19500   -7.2  19.0   280   19   10   6.8   3.7   36.7  98.1     5.7      M    M
 19000   -6.1  21.0   275   19   10   7.8   4.3   36.2  97.2     5.3      M    M
 18500   -5.0  23.0   275   19   10   7.7   4.2   35.9  96.5     5.0      M    M
 18000   -3.8  25.2   275   18    9   7.7   4.2   35.5  95.9     4.6      M    M
 17500   -2.7  27.1   275   18    9   7.7   4.2   35.2  95.3     4.4      M    M
 17000   -1.7  28.9   270   18    9   3.4   1.9   34.8  94.6     4.0      M    M
 16500   -1.5  29.3   270   17    9  -0.3  -0.2   33.3  91.9     2.7      M    M
 16000   -1.8  28.8   270   17    9   3.3   1.8   31.5  88.7     1.0      M    M
 15500   -1.0  30.2   275   15    8   5.7   3.1   30.8  87.5     0.3      M    M
 15000    0.4  32.7   280   10    5   7.1   3.9   29.9  85.9    -0.5    908  4.6
 14500    1.5  34.7   290    8    4   7.5   4.1   29.6  85.2    -0.8    860  4.4
 14000    2.7  36.9   305    6    3   8.9   4.9   29.3  84.7    -1.1    810  4.1
 13500    4.1  39.4   310    6    3   9.3   5.1   29.2  84.5    -1.2    753  3.8
 13000    5.5  41.9   315    5    3   9.3   5.1   29.1  84.4    -1.2    697  3.5
 12500    6.9  44.4   325    5    3   9.3   5.1   29.1  84.3    -1.3    640  3.3
 12000    8.3  46.9   330    5    3   9.3   5.1   29.0  84.2    -1.3    583  3.0
 11500    9.7  49.5   340    6    3  10.0   5.5   29.0  84.1    -1.4    526  2.7
 11000   11.2  52.2   350    7    4  10.1   5.6   29.0  84.2    -1.4    467  2.4
 10500   12.7  54.9   355    8    4   9.6   5.3   29.1  84.4    -1.3    407  2.1
 10250   13.4  56.1   350    8    4   8.6   4.7   29.0  84.3    -1.4    380  1.9
 10000   14.0  57.2   345    7    4   8.7   4.8   28.9  84.1    -1.5    353  1.8
  9750   14.7  58.5   340    7    3   8.6   4.7   28.9  83.9    -1.6    326  1.7
  9500   15.3  59.5   330    6    3   8.8   4.8   28.8  83.8    -1.6    298  1.5
  9250   16.0  60.8   325    6    3   8.2   4.5   28.7  83.7    -1.7    271  1.4
  9000   16.5  61.7   315    6    3   7.5   4.1   28.6  83.4    -1.9    247  1.3
  8750   17.1  62.8   310    8    4   7.7   4.2   28.4  83.1    -2.0    223  1.1
  8500   17.7  63.9   310    9    5   7.7   4.2   28.2  82.8    -2.2    199  1.0
  8250   18.2  64.8   305   11    5   7.7   4.2   28.1  82.6    -2.4    175  0.9
  8000   18.8  65.8   305   12    6   7.7   4.2   27.9  82.3    -2.5    150  0.8
  7750   19.4  66.9   300   12    6   7.7   4.2   27.8  82.0    -2.7    126  0.6
  7500   19.9  67.8   300   11    6   7.7   4.2   27.6  81.7    -2.9    102  0.5
  7250   20.5  68.9   295   11    6   7.7   4.2   27.5  81.4    -3.1     78  0.4
  7000   21.0  69.8   290   11    6   7.5   4.1   27.3  81.1    -3.2     54  0.3
  6750   21.6  70.9   290   10    5   8.4   4.6   27.1  80.9    -3.4     29  0.1
  6500   22.2  72.0   290    9    5   5.1   2.8   27.0  80.6    -3.6      5  0.0
  6250   22.3  72.1   290    8    4   2.1   1.1   26.4  79.6    -4.1      M    M
  6000   22.5  72.5   290    7    4   0.7   0.4   25.9  78.6    -4.7      M    M
  5750   22.3  72.1   275    5    3  -7.7  -4.2   24.9  76.8    -5.7      M    M
  5500   21.1  70.0   245    4    2 -22.1 -12.2   23.1  73.6    -7.6      7  0.0

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

           08/27/2015 at 0900 MDT          |       08/27/2015 at 1200 MDT
                                           |
K index... +30.9  LI... -0.7               | K index... +28.2  LI... -2.3
CAPE... +20.0  CIN... -20.0                | CAPE... +423.7  CIN... -39.3
                                           |
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 -65.5 -85.9  285  29 15   2.7   1.5 | -65.4 -85.7  275  28 14   2.6   1.4
 45000 -60.4 -76.7  285  44 23   4.9   2.7 | -60.6 -77.1  280  42 22   4.6   2.5
 40000 -52.3 -62.1  285  43 22   7.1   3.9 | -52.6 -62.7  275  42 21   7.7   4.2
 38000 -48.0 -54.4  280  39 20   7.1   3.9 | -48.0 -54.4  270  35 18   7.6   4.2
 36000 -43.8 -46.8  275  34 18   7.4   4.1 | -43.4 -46.1  255  29 15   8.0   4.4
 34000 -38.7 -37.7  275  31 16   8.6   4.7 | -38.1 -36.6  260  28 14   8.9   4.9
 32000 -33.5 -28.3  280  28 14   8.4   4.6 | -32.8 -27.0  270  27 14   8.8   4.8
 30000 -28.5 -19.3  280  24 13   8.3   4.6 | -28.1 -18.6  280  24 12   7.7   4.2
 29000 -25.4 -13.7  275  22 11   8.4   4.6 | -25.3 -13.5  285  22 11   7.7   4.2
 28000 -23.0  -9.4  275  21 11   7.3   4.0 | -23.0  -9.4  290  21 11   7.3   4.0
 27000 -20.8  -5.4  275  20 11   7.4   4.1 | -20.9  -5.6  290  20 10   7.3   4.0
 26000 -18.7  -1.7  275  20 10   7.4   4.1 | -18.7  -1.7  290  18  9   7.3   4.0
 25000 -16.5   2.3  280  20 10   6.8   3.7 | -16.5   2.3  295  17  9   7.0   3.8
 24000 -14.7   5.5  275  19 10   5.9   3.2 | -14.6   5.7  290  17  9   6.6   3.6
 23000 -13.0   8.6  275  19 10   6.0   3.3 | -12.7   9.1  290  17  9   6.7   3.6
 22000 -11.3  11.7  275  18  9   6.1   3.4 | -10.8  12.6  290  17  9   6.4   3.5
 21000  -9.5  14.9  280  17  9   6.3   3.5 |  -9.0  15.8  285  16  8   6.0   3.3
 20000  -7.7  18.1  280  15  8   6.4   3.5 |  -7.3  18.9  285  16  8   6.0   3.3
 19500  -6.8  19.8  280  14  7   6.7   3.7 |  -6.4  20.5  285  16  8   6.1   3.3
 19000  -6.0  21.2  280  13  7   4.2   2.3 |  -5.6  21.9  285  15  8   5.8   3.2
 18500  -5.4  22.3  280  13  6   4.5   2.5 |  -4.7  23.5  285  15  8   5.8   3.2
 18000  -4.8  23.4  280  12  6   5.9   3.2 |  -3.9  25.0  285  15  8   6.0   3.3
 17500  -3.7  25.3  280  11  5   8.0   4.4 |  -3.0  26.6  290  15  8   6.2   3.4
 17000  -2.5  27.5  280  10  5   8.2   4.5 |  -2.1  28.2  290  14  7   6.2   3.4
 16500  -1.5  29.3  280   9  5   5.9   3.2 |  -1.3  29.7  290  14  7   6.2   3.4
 16000  -0.7  30.7  285   9  5   6.0   3.3 |  -0.4  31.3  290  14  7   6.2   3.4
 15500   0.6  33.1  285   9  5   5.2   2.8 |   1.0  33.8  290  14  7   6.1   3.3
 15000   1.3  34.3  285   9  5   5.2   2.9 |   1.9  35.4  290  13  7   6.1   3.3
 14500   2.1  35.8  285   9  5   5.7   3.2 |   2.7  36.9  290  13  7   6.2   3.4
 14000   2.9  37.2  280   9  5   5.8   3.2 |   3.6  38.5  290  13  7   6.3   3.4
 13500   3.7  38.7  280  10  5   6.4   3.5 |   4.5  40.1  290  13  7   6.6   3.6
 13000   4.7  40.5  280  10  5   6.8   3.7 |   5.5  41.9  295  13  7   6.9   3.8
 12500   5.7  42.3  280  10  5   7.2   3.9 |   6.5  43.7  295  13  6   6.8   3.7
 12000   6.8  44.2  280   9  5   7.7   4.2 |   7.4  45.3  300  12  6   6.6   3.6
 11500   8.0  46.4  280   9  4   7.7   4.2 |   8.3  46.9  305  11  6   6.8   3.7
 11000   9.1  48.4  280   8  4   7.4   4.1 |   9.4  48.9  305  11  6   7.0   3.9
 10500  10.3  50.5  275   7  4   3.9   2.1 |  10.4  50.7  310  11  5   2.8   1.6
 10250  10.4  50.7  275   7  4   5.4   3.0 |  10.5  50.9  310  11  5   5.1   2.8
 10000  11.2  52.2  270   7  4  11.4   6.3 |  11.3  52.3  310  10  5  12.3   6.7
  9750  12.0  53.6  265   7  4  10.5   5.8 |  12.1  53.8  315  10  5  10.8   5.9
  9500  12.7  54.9  260   8  4   8.7   4.8 |  12.8  55.0  315  10  5   9.4   5.1
  9250  13.2  55.8  260   8  4   6.1   3.3 |  13.4  56.1  315  10  5   6.8   3.8
  9000  13.8  56.8  260   9  5   8.1   4.4 |  14.0  57.2  315  10  5   9.1   5.0
  8750  14.4  57.9  260   9  5   9.4   5.2 |  14.7  58.5  315   9  5  10.9   6.0
  8500  15.1  59.2  260  10  5   8.4   4.6 |  15.5  59.9  315   9  5   9.1   5.0
  8250  15.7  60.3  260  10  5   7.6   4.1 |  16.0  60.8  315   8  4   7.7   4.2
  8000  16.3  61.3  260  10  5   8.0   4.4 |  16.6  61.9  310   7  4   7.6   4.2
  7750  16.9  62.4  260  10  5   8.3   4.6 |  17.1  62.8  305   7  3   7.0   3.9
  7500  17.5  63.5  265  10  5   7.8   4.3 |  17.6  63.7  300   6  3   6.1   3.3
  7250  18.0  64.4  265  10  5   7.5   4.1 |  18.0  64.4  285   5  3   5.4   3.0
  7000  18.6  65.5  265  10  5   7.6   4.2 |  18.3  64.9  270   5  3   5.3   2.9
  6750  19.2  66.6  265  10  5   7.3   4.0 |  18.7  65.7  255   6  3   5.6   3.1
  6500  19.7  67.5  260   9  5   7.0   3.8 |  19.1  66.4  245   6  3   6.8   3.8
  6250  20.2  68.4  260   9  4   6.9   3.8 |  19.6  67.3  235   7  3   8.1   4.5
  6000  20.7  69.3  260   8  4   7.0   3.8 |  20.1  68.2  230   7  4   5.3   2.9
  5750  21.3  70.3  260   9  4   7.6   4.2 |  20.5  68.9  225   7  4  11.4   6.2
  5500  21.8  71.2  255   7  3   8.3   4.6 |  22.0  71.6  225   7  4  29.0  15.9

           08/27/2015 at 1500 MDT          |       08/27/2015 at 1800 MDT
                                           |
K index... +28.1  LI... -1.7               | K index... +23.3  LI... -1.4
CAPE... +164.0  CIN... -9.9                | CAPE... +159.2  CIN... -44.4
                                           |
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 -65.3 -85.5  265  30 16   2.2   1.2 | -64.7 -84.5  260  31 16   2.3   1.3
 45000 -60.9 -77.6  270  43 22   4.7   2.6 | -60.3 -76.5  260  44 23   4.2   2.3
 40000 -52.7 -62.9  275  42 22   7.9   4.4 | -52.9 -63.2  270  42 22   8.0   4.4
 38000 -48.0 -54.4  270  34 17   7.9   4.3 | -48.1 -54.6  260  32 17   7.9   4.3
 36000 -43.2 -45.8  260  26 14   8.2   4.5 | -43.4 -46.1  250  23 12   8.2   4.5
 34000 -37.9 -36.2  260  26 13   9.0   4.9 | -38.1 -36.6  260  20 11   8.9   4.9
 32000 -32.5 -26.5  255  26 13   8.9   4.9 | -32.8 -27.0  265  19 10   8.8   4.8
 30000 -27.9 -18.2  270  23 12   7.6   4.2 | -28.3 -18.9  275  19 10   7.2   4.0
 29000 -25.1 -13.2  280  21 11   7.6   4.2 | -25.7 -14.3  285  20 10   7.3   4.0
 28000 -22.9  -9.2  285  20 10   6.7   3.7 | -23.5 -10.3  290  20 10   7.4   4.1
 27000 -20.8  -5.4  290  18  9   6.8   3.7 | -21.3  -6.3  290  20 10   7.4   4.1
 26000 -18.8  -1.8  295  16  8   6.8   3.8 | -19.1  -2.4  295  19 10   7.4   4.1
 25000 -16.8   1.8  300  14  7   6.8   3.7 | -17.0   1.4  295  19 10   7.0   3.8
 24000 -14.8   5.4  300  15  8   6.8   3.7 | -15.1   4.8  300  18  9   6.3   3.4
 23000 -12.8   9.0  300  15  8   6.8   3.7 | -13.2   8.2  310  18  9   6.3   3.4
 22000 -10.8  12.6  300  16  8   6.4   3.5 | -11.4  11.5  320  18  9   6.3   3.5
 21000  -9.1  15.6  300  16  8   5.9   3.2 |  -9.5  14.9  320  20 10   6.4   3.5
 20000  -7.4  18.7  295  17  9   6.0   3.3 |  -7.5  18.5  320  22 11   6.4   3.5
 19500  -6.6  20.1  295  17  9   6.1   3.3 |  -6.6  20.1  320  23 12   6.0   3.3
 19000  -5.8  21.6  295  18  9   5.3   2.9 |  -5.4  22.3  320  24 12   9.4   5.1
 18500  -5.0  23.0  300  18  9   5.4   2.9 |  -4.0  24.8  320  24 12   9.0   4.9
 18000  -4.2  24.4  300  18  9   5.5   3.0 |  -2.7  27.1  320  24 12   7.8   4.3
 17500  -3.4  25.9  305  18  9   5.8   3.2 |  -1.7  28.9  320  24 12   6.2   3.4
 17000  -2.5  27.5  305  18  9   5.8   3.2 |  -0.8  30.6  315  24 12   6.4   3.5
 16500  -1.7  28.9  310  19 10   6.0   3.3 |  -0.1  31.8  315  24 12   4.2   2.3
 16000  -0.8  30.6  310  19 10   6.0   3.3 |   0.5  32.9  315  24 12   4.4   2.4
 15500   0.6  33.1  315  20 10   6.4   3.5 |   1.1  34.0  315  24 12   4.6   2.5
 15000   1.5  34.7  315  21 11   6.4   3.5 |   2.0  35.6  320  25 13   4.7   2.6
 14500   2.4  36.3  320  21 11   6.4   3.5 |   2.6  36.7  320  25 13   6.0   3.3
 14000   3.3  37.9  320  22 11   6.4   3.5 |   3.4  38.1  320  25 13   6.3   3.4
 13500   4.3  39.7  320  22 11   6.7   3.7 |   4.2  39.6  320  25 13   7.0   3.9
 13000   5.3  41.5  315  22 11   6.9   3.8 |   5.3  41.5  320  23 12   7.5   4.1
 12500   6.2  43.2  315  22 11   7.4   4.1 |   6.3  43.3  320  21 11   7.8   4.3
 12000   7.3  45.1  310  19 10   8.2   4.5 |   7.5  45.5  315  19 10   8.1   4.4
 11500   8.4  47.1  310  17  9   8.4   4.6 |   8.7  47.7  315  17  9   8.1   4.4
 11000   9.7  49.5  310  15  8   8.6   4.7 |   9.9  49.8  315  16  8   7.8   4.3
 10500  10.9  51.6  310  14  7   4.9   2.7 |  11.0  51.8  315  14  7   4.1   2.3
 10250  11.1  52.0  305  14  7   7.0   3.8 |  11.2  52.2  315  14  7   6.1   3.4
 10000  12.0  53.6  305  14  7  13.4   7.4 |  12.0  53.6  315  13  7  12.6   6.9
  9750  12.9  55.2  305  14  7  12.3   6.8 |  12.8  55.0  320  13  6  11.3   6.2
  9500  13.8  56.8  305  14  7  10.2   5.6 |  13.6  56.5  320  12  6   9.9   5.4
  9250  14.4  57.9  305  14  7   7.7   4.2 |  14.2  57.6  325  11  6   7.7   4.2
  9000  15.1  59.2  305  14  7  10.3   5.7 |  14.9  58.8  330  11  6   9.6   5.2
  8750  15.9  60.6  305  13  7  11.7   6.4 |  15.6  60.1  335  10  5  10.6   5.8
  8500  16.8  62.2  305  13  7  10.5   5.8 |  16.4  61.5  335  10  5  10.0   5.5
  8250  17.5  63.5  305  13  7   9.4   5.1 |  17.1  62.8  340  10  5   9.7   5.3
  8000  18.2  64.8  305  13  7  10.0   5.5 |  17.8  64.0  345  10  5   9.7   5.3
  7750  19.0  66.2  305  13  7  10.6   5.8 |  18.6  65.5  350  10  5   9.8   5.4
  7500  19.7  67.5  305  13  7  10.1   5.5 |  19.3  66.7  355  10  5  10.1   5.5
  7250  20.5  68.9  305  13  7   9.9   5.4 |  20.0  68.0  355  10  5  10.5   5.7
  7000  21.2  70.2  305  13  7   9.7   5.3 |  20.8  69.4  355  10  5  10.0   5.5
  6750  21.9  71.4  305  13  6   9.6   5.3 |  21.5  70.7  360  10  5   9.3   5.1
  6500  22.7  72.9  305  12  6  10.5   5.8 |  22.2  72.0  360  10  5  10.0   5.5
  6250  23.5  74.3  305  12  6  11.6   6.3 |  23.0  73.4  360  10  5  10.8   5.9
  6000  24.3  75.7  305  12  6   9.4   5.2 |  23.8  74.8  360  10  5   9.8   5.4
  5750  25.0  77.0  305  12  6  13.0   7.1 |  24.5  76.1  360  10  5  11.1   6.1
  5500  26.5  79.7  305  11  6  25.2  13.8 |  25.5  77.9  360  10  5  16.2   8.9
________________________________________________________________________________

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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