Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 240022
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1822 MDT Thursday, July 23, 2015

This forecast is for Friday, July 24, 2015:

If the trigger temperature of 85.3 F/29.6 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 891 ft/min (4.5 m/s)
   Maximum height of thermals.................. 17001 ft MSL (11694 ft AGL)

Forecast maximum temperature................... 92.0 F/33.8 C
Time of trigger temperature.................... 1130 MDT
Time of overdevelopment........................ None
Middle/high clouds during soaring window....... Overcast opaque high
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 10427 ft MSL (5121 ft AGL)
Thermal soaring outlook for Saturday 07/25..... 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....................... 40920 ft MSL (35613 ft AGL)
Wave soaring outlook for Saturday 07/25........ Poor

Remarks...

Sunrise/Sunset.................... 05:51:11 / 20:20:59 MDT
Total possible sunshine........... 14 hr 29 min 48 sec (869 min 48 sec)
Altitude of sun at 13:05:56 MDT... 70.01 degrees

Upper air data from numerical model forecast valid on 07/24/2015 at 0600 MDT

Freezing level.................. 16245 ft MSL (10938 ft AGL)
Convective condensation level... 18071 ft MSL (12764 ft AGL)
Lifted condensation level....... 17852 ft MSL (12545 ft AGL)
Lifted index.................... +1.1
K index......................... +22.5

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  -66.5 -87.7   255   29   15   0.9   0.5      M     M       M      M    M
 45000  -62.1 -79.8   255   49   25   6.9   3.8      M     M       M      M    M
 40000  -51.0 -59.8   260   64   33   8.1   4.4      M     M       M      M    M
 38000  -46.1 -51.0   260   62   32   8.1   4.4      M     M       M      M    M
 36000  -41.3 -42.3   260   60   31   7.7   4.2      M     M       M      M    M
 34000  -36.8 -34.2   255   51   26   7.4   4.0      M     M       M      M    M
 32000  -32.4 -26.3   250   43   22   7.8   4.3      M     M       M      M    M
 30000  -28.0 -18.4   245   36   19   7.3   4.0   48.4 119.1    11.4      M    M
 29000  -25.3 -13.5   240   33   17   7.3   4.0   47.3 117.1    10.8      M    M
 28000  -23.1  -9.6   235   31   16   7.4   4.0   46.4 115.5    10.2      M    M
 27000  -20.9  -5.6   235   30   16   7.4   4.0   45.4 113.7     9.5      M    M
 26000  -18.7  -1.7   235   30   15   7.4   4.0   44.5 112.1     8.9      M    M
 25000  -16.5   2.3   235   29   15   7.0   3.8   43.7 110.7     8.4      M    M
 24000  -14.5   5.9   235   28   14   6.9   3.8   42.6 108.6     7.5      M    M
 23000  -12.4   9.7   230   27   14   7.0   3.8   41.5 106.8     6.7      M    M
 22000  -10.5  13.1   230   26   13   5.3   2.9   40.6 105.0     5.9      M    M
 21000   -9.2  15.4   235   26   14   4.7   2.6   38.6 101.6     4.3      M    M
 20000   -7.9  17.8   235   27   14   5.0   2.7   36.9  98.5     2.7      M    M
 19500   -7.2  19.0   235   27   14   5.4   3.0   36.2  97.1     1.9      M    M
 19000   -6.3  20.7   235   26   13   7.7   4.2   35.6  96.2     1.4      M    M
 18500   -5.2  22.6   240   23   12   7.6   4.1   35.3  95.5     1.1      M    M
 18000   -4.1  24.6   240   21   11   7.9   4.3   34.9  94.8     0.7      M    M
 17500   -3.0  26.6   235   19   10   8.0   4.4   34.6  94.3     0.4      M    M
 17000   -1.8  28.8   235   16    8   7.9   4.4   34.3  93.8     0.1      M    M
 16500   -0.8  30.6   240   15    8   7.0   3.8   33.9  93.1    -0.3   1053  5.4
 16000    0.3  32.5   240   13    7   7.0   3.8   33.5  92.2    -0.7   1007  5.1
 15500    1.4  34.5   240   12    6   8.4   4.6   33.1  91.6    -1.1    959  4.9
 15000    3.2  37.8   240    8    4   8.5   4.7   32.8  91.0    -1.4    882  4.5
 14500    4.5  40.1   235    7    3   8.3   4.6   32.6  90.6    -1.7    830  4.2
 14000    5.7  42.3   235    5    3   8.3   4.6   32.3  90.2    -1.9    778  4.0
 13500    7.0  44.6   240    4    2   8.7   4.8   32.1  89.9    -2.1    726  3.7
 13000    8.3  46.9   255    4    2   8.8   4.8   32.0  89.6    -2.2    671  3.4
 12500    9.6  49.3   270    5    2   8.7   4.8   31.8  89.3    -2.4    617  3.1
 12000   11.0  51.8   290    6    3   8.7   4.8   31.7  89.0    -2.5    561  2.8
 11500   12.4  54.3   300    8    4   8.5   4.7   31.5  88.7    -2.6    505  2.6
 11000   13.6  56.5   315   10    5   8.1   4.4   31.3  88.3    -2.7    452  2.3
 10500   14.9  58.8   325   12    6   4.6   2.5   31.1  87.9    -2.9    398  2.0
 10250   15.1  59.2   325   12    6   5.8   3.2   30.5  87.0    -3.5    385  2.0
 10000   15.9  60.6   330   12    6  11.2   6.2   30.6  87.0    -3.4    355  1.8
  9750   16.6  61.9   335   12    6  10.3   5.6   30.6  87.1    -3.4    325  1.7
  9500   17.4  63.3   340   12    6   8.5   4.6   30.6  87.1    -3.4    295  1.5
  9250   17.9  64.2   340   12    6   7.0   3.8   30.4  86.7    -3.6    273  1.4
  9000   18.5  65.3   345   12    6   9.3   5.1   30.3  86.5    -3.8    247  1.3
  8750   19.2  66.6   350   12    6   9.8   5.4   30.3  86.5    -3.8    219  1.1
  8500   19.9  67.8   355   11    6   8.9   4.9   30.3  86.5    -3.9    191  1.0
  8250   20.5  68.9   350   11    6   8.4   4.6   30.2  86.3    -4.0    165  0.8
  8000   21.1  70.0   350   11    6   8.4   4.6   30.1  86.1    -4.1    140  0.7
  7750   21.7  71.1   350   11    6   8.0   4.4   30.0  85.9    -4.3    114  0.6
  7500   22.3  72.1   345   11    5   7.9   4.3   29.8  85.7    -4.4     89  0.5
  7250   22.9  73.2   345   11    6   7.5   4.1   29.7  85.4    -4.6     65  0.3
  7000   23.4  74.1   345   11    6   8.5   4.6   29.5  85.1    -4.7     40  0.2
  6750   24.0  75.2   340   11    6   5.0   2.7   29.4  84.8    -4.9     15  0.1
  6500   24.1  75.4   335   11    5   0.4   0.2   28.8  83.8    -5.5      4  0.0
  6250   24.0  75.2   330   10    5  -4.0  -2.2   27.9  82.3    -6.4      1  0.0
  6000   23.8  74.8   320   10    5   9.7   5.3   27.1  80.8    -7.3      M    M
  5750   24.7  76.5   320   12    6  -5.0  -2.7   27.2  81.0    -7.2      M    M
  5500   21.5  70.7   300    6    3 -68.0 -37.3   23.7  74.7   -11.1     54  0.3

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

           07/24/2015 at 0900 MDT          |       07/24/2015 at 1200 MDT
                                           |
K index... +22.3  LI... +0.9               | K index... +22.8  LI... +0.9
CAPE... 0.0  CIN... -0.6                   | CAPE... 0.0  CIN... -1.0
                                           |
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 -66.6 -87.9  250  30 15   0.8   0.4 | -67.0 -88.6  250  36 18   1.1   0.6
 45000 -62.3 -80.1  255  49 25   6.9   3.8 | -61.8 -79.2  260  52 27   7.0   3.9
 40000 -51.0 -59.8  255  63 32   8.2   4.5 | -51.1 -60.0  255  62 32   7.6   4.2
 38000 -46.1 -51.0  255  61 31   8.2   4.5 | -46.5 -51.7  255  60 31   7.6   4.2
 36000 -41.2 -42.2  255  59 31   7.5   4.1 | -41.9 -43.4  250  58 30   8.2   4.5
 34000 -36.9 -34.4  255  52 27   7.1   3.9 | -36.8 -34.2  245  54 28   8.6   4.7
 32000 -32.7 -26.9  250  44 22   7.7   4.2 | -31.7 -25.1  240  50 26   9.3   5.1
 30000 -28.2 -18.8  250  39 20   7.6   4.1 | -26.8 -16.2  245  45 23   7.2   3.9
 29000 -25.3 -13.5  250  36 18   7.6   4.1 | -24.7 -12.5  245  43 22   7.2   3.9
 28000 -23.2  -9.8  245  34 17   6.4   3.5 | -22.7  -8.9  245  41 21   6.4   3.5
 27000 -21.3  -6.3  245  33 17   6.5   3.6 | -20.8  -5.4  250  37 19   6.5   3.6
 26000 -19.4  -2.9  245  32 16   6.6   3.6 | -18.8  -1.8  250  34 17   6.5   3.6
 25000 -17.5   0.5  240  31 16   6.6   3.6 | -16.9   1.6  250  31 16   6.3   3.4
 24000 -15.6   3.9  240  31 16   6.7   3.7 | -15.1   4.8  250  29 15   6.2   3.4
 23000 -13.6   7.5  240  31 16   6.8   3.7 | -13.3   8.1  250  27 14   6.2   3.4
 22000 -11.7  10.9  235  31 16   6.6   3.6 | -11.5  11.3  250  25 13   6.6   3.6
 21000  -9.8  14.4  235  29 15   6.6   3.6 |  -9.6  14.7  250  23 12   6.7   3.7
 20000  -7.9  17.8  235  28 14   6.6   3.6 |  -7.7  18.1  250  21 11   6.7   3.7
 19500  -7.0  19.4  230  27 14   6.8   3.7 |  -6.7  19.9  250  19 10   6.5   3.6
 19000  -5.9  21.4  230  25 13   7.3   4.0 |  -5.9  21.4  250  18  9   5.7   3.1
 18500  -4.9  23.2  235  23 12   7.4   4.0 |  -5.1  22.8  250  16  8   5.7   3.1
 18000  -3.9  25.0  235  21 11   6.9   3.8 |  -4.3  24.3  245  14  7   6.1   3.3
 17500  -2.9  26.8  235  20 10   6.8   3.7 |  -3.4  25.9  240  13  7   6.2   3.4
 17000  -1.9  28.6  235  18  9   7.0   3.8 |  -2.5  27.5  235  12  6   6.3   3.5
 16500  -0.8  30.6  235  16  8   7.7   4.2 |  -1.5  29.3  225  11  6   6.9   3.8
 16000   0.3  32.5  230  14  7   7.7   4.2 |   0.0  32.0  215  11  6   7.6   4.2
 15500   2.0  35.6  230  12  6   7.3   4.0 |   1.3  34.3  210  10  5   8.8   4.9
 15000   3.0  37.4  225  10  5   7.3   4.0 |   2.6  36.7  205  10  5   8.9   4.9
 14500   4.2  39.6  225   9  5   8.3   4.6 |   3.9  39.0  200   9  5   8.7   4.8
 14000   5.4  41.7  220   7  4   8.3   4.5 |   5.3  41.5  200   9  4   8.8   4.8
 13500   6.7  44.1  220   5  3   8.2   4.5 |   6.5  43.7  200   7  4   7.6   4.2
 13000   8.0  46.4  240   4  2   8.2   4.5 |   7.7  45.9  205   6  3   7.6   4.2
 12500   9.2  48.6  280   3  2   7.7   4.3 |   9.0  48.2  210   4  2   8.2   4.5
 12000  10.5  50.9  320   4  2   7.7   4.2 |  10.3  50.5  205   2  1   8.4   4.6
 11500  11.7  53.1  340   6  3   8.5   4.7 |  11.7  53.1  175   1  0   8.9   4.9
 11000  13.0  55.4  345   6  3   8.8   4.8 |  13.0  55.4  230   1  0   9.1   5.0
 10500  14.2  57.6  345   7  4   4.7   2.6 |  14.3  57.7  255   1  1   3.9   2.1
 10250  14.5  58.1  345   7  4   6.5   3.6 |  14.5  58.1  260   2  1   6.1   3.3
 10000  15.3  59.5  345   7  4  11.6   6.4 |  15.2  59.4  265   2  1  11.7   6.4
  9750  16.0  60.8  340   7  4  10.4   5.7 |  16.0  60.8  275   2  1  10.1   5.5
  9500  16.8  62.2  340   7  4   7.8   4.3 |  16.7  62.1  280   2  1   7.9   4.3
  9250  17.2  63.0  340   7  4   6.3   3.4 |  17.2  63.0  280   1  1   6.8   3.7
  9000  17.8  64.0  345   7  4   9.5   5.2 |  17.8  64.0  285   1  0   9.2   5.1
  8750  18.6  65.5  350   8  4  10.2   5.6 |  18.5  65.3  000   0  0   9.6   5.3
  8500  19.3  66.7  355   8  4   8.3   4.6 |  19.2  66.6  000   0  0   8.4   4.6
  8250  19.8  67.6  360   8  4   7.3   4.0 |  19.7  67.5  100   1  0   8.0   4.4
  8000  20.4  68.7  005   9  4   7.7   4.2 |  20.3  68.5  100   1  1   8.4   4.6
  7750  20.9  69.6  010   9  5   7.4   4.1 |  20.8  69.4  115   1  0   9.2   5.1
  7500  21.4  70.5  015   9  5   6.8   3.7 |  21.5  70.7  125   1  0  10.0   5.5
  7250  21.9  71.4  015   9  5   6.3   3.5 |  22.2  72.0  130   1  0  10.3   5.7
  7000  22.4  72.3  020  10  5   7.3   4.0 |  23.0  73.4  140   1  0   9.8   5.4
  6750  22.9  73.2  025  10  5   5.8   3.2 |  23.7  74.7  140   1  0   9.8   5.4
  6500  23.2  73.8  020   9  5   3.5   1.9 |  24.4  75.9  140   1  0  10.3   5.7
  6250  23.3  73.9  015   8  4   3.5   1.9 |  25.2  77.4  140   1  0  10.0   5.5
  6000  23.5  74.3  010   7  4   4.7   2.6 |  25.9  78.6  140   1  0  10.8   5.9
  5750  23.9  75.0  010   6  3   9.3   5.1 |  26.9  80.4  140   1  0  16.2   8.9
  5500  24.6  76.3  360   4  2  13.2   7.3 |  28.4  83.1  135   1  0  22.8  12.5

           07/24/2015 at 1500 MDT          |       07/24/2015 at 1800 MDT
                                           |
K index... +26.7  LI... +0.5               | K index... +28.1  LI... -1.0
CAPE... 0.0  CIN... -0.9                   | CAPE... +18.9  CIN... -51.9
                                           |
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 -67.5 -89.5  250  38 20   0.9   0.5 | -67.7 -89.9  250  34 17   1.3   0.7
 45000 -62.1 -79.8  255  49 25   7.5   4.1 | -62.1 -79.8  255  47 24   7.2   4.0
 40000 -50.7 -59.3  250  55 28   7.9   4.3 | -51.0 -59.8  250  57 29   8.4   4.6
 38000 -46.0 -50.8  255  56 29   7.9   4.3 | -46.0 -50.8  245  58 30   8.4   4.6
 36000 -41.2 -42.2  255  57 29   8.0   4.4 | -40.9 -41.6  245  58 30   8.3   4.6
 34000 -36.4 -33.5  250  51 26   8.1   4.4 | -36.0 -32.8  245  53 27   8.3   4.5
 32000 -31.5 -24.7  245  46 23   8.7   4.8 | -31.0 -23.8  240  49 25   9.1   5.0
 30000 -26.5 -15.7  240  40 21   7.5   4.1 | -25.9 -14.6  245  41 21   7.7   4.2
 29000 -24.3 -11.7  235  38 20   7.5   4.1 | -23.6 -10.5  245  38 19   7.7   4.2
 28000 -22.1  -7.8  235  36 19   7.2   3.9 | -21.5  -6.7  245  34 18   6.6   3.6
 27000 -20.0  -4.0  235  34 18   7.2   4.0 | -19.6  -3.3  250  30 16   6.7   3.7
 26000 -17.9  -0.2  235  32 17   7.3   4.0 | -17.6   0.3  250  27 14   6.7   3.7
 25000 -15.8   3.6  235  30 16   6.3   3.4 | -15.7   3.7  255  23 12   6.3   3.4
 24000 -14.0   6.8  240  27 14   6.0   3.3 | -13.9   7.0  255  19 10   6.1   3.4
 23000 -12.3   9.9  240  23 12   6.0   3.3 | -12.1  10.2  255  15  8   6.1   3.4
 22000 -10.6  12.9  245  20 10   6.1   3.3 | -10.3  13.5  260  11  6   5.7   3.1
 21000  -8.8  16.2  245  17  9   6.2   3.4 |  -8.7  16.3  270  10  5   5.6   3.1
 20000  -7.0  19.4  240  13  7   6.2   3.4 |  -7.1  19.2  285  10  5   5.6   3.1
 19500  -6.1  21.0  240  12  6   6.3   3.4 |  -6.3  20.7  295  10  5   5.8   3.2
 19000  -5.2  22.6  240  10  5   6.6   3.6 |  -5.4  22.3  295  10  5   6.6   3.6
 18500  -4.3  24.3  240   9  5   6.6   3.6 |  -4.4  24.1  300   8  4   6.5   3.6
 18000  -3.3  26.1  240   8  4   6.4   3.5 |  -3.5  25.7  305   8  4   6.0   3.3
 17500  -2.4  27.7  245   7  4   6.4   3.5 |  -2.7  27.1  305   8  4   5.9   3.2
 17000  -1.5  29.3  250   6  3   6.3   3.5 |  -1.8  28.8  305   8  4   6.0   3.3
 16500  -0.6  30.9  255   6  3   6.0   3.3 |  -0.9  30.4  305   7  4   6.8   3.7
 16000   0.7  33.3  265   5  3   6.2   3.4 |   0.5  32.9  295   5  3   7.3   4.0
 15500   1.7  35.1  265   5  3   6.8   3.7 |   1.8  35.2  290   5  3   8.7   4.8
 15000   2.7  36.9  260   5  2   6.7   3.7 |   3.1  37.6  285   5  2   8.6   4.7
 14500   3.8  38.8  250   4  2   8.4   4.6 |   4.4  39.9  280   4  2   9.4   5.2
 14000   5.0  41.0  240   3  2   8.3   4.6 |   5.8  42.4  275   4  2   9.4   5.1
 13500   6.2  43.2  215   3  1   7.8   4.3 |   7.2  45.0  270   4  2   9.1   5.0
 13000   7.3  45.1  190   3  1   7.8   4.3 |   8.6  47.5  265   4  2   9.1   5.0
 12500   8.5  47.3  170   3  2   7.5   4.1 |   9.9  49.8  260   4  2   9.0   5.0
 12000   9.6  49.3  165   4  2   7.4   4.1 |  11.3  52.3  250   4  2   9.0   4.9
 11500  10.8  51.4  160   4  2   8.0   4.4 |  12.6  54.7  235   3  2   8.3   4.6
 11000  12.0  53.6  160   5  2   8.2   4.5 |  13.7  56.7  210   3  2   7.6   4.2
 10500  13.2  55.8  165   5  3   4.1   2.3 |  14.9  58.8  195   4  2   3.9   2.2
 10250  13.5  56.3  165   5  3   6.8   3.8 |  15.0  59.0  190   4  2   4.9   2.7
 10000  14.3  57.7  170   5  3  12.7   6.9 |  15.7  60.3  185   5  3  10.2   5.6
  9750  15.2  59.4  175   6  3  11.3   6.2 |  16.4  61.5  180   6  3   9.3   5.1
  9500  15.9  60.6  180   6  3   8.6   4.7 |  17.0  62.6  175   6  3   7.1   3.9
  9250  16.5  61.7  180   6  3   7.0   3.8 |  17.4  63.3  180   7  4   5.8   3.2
  9000  17.1  62.8  185   6  3   9.8   5.4 |  18.0  64.4  180   7  4   9.0   5.0
  8750  17.9  64.2  185   7  3  10.5   5.7 |  18.7  65.7  180   8  4   9.7   5.3
  8500  18.6  65.5  185   7  3  10.1   5.5 |  19.3  66.7  180   8  4   9.2   5.1
  8250  19.4  66.9  190   7  3  10.0   5.5 |  20.0  68.0  180   8  4   9.1   5.0
  8000  20.1  68.2  190   7  3  10.2   5.6 |  20.6  69.1  185   8  4   9.0   5.0
  7750  20.9  69.6  190   7  3  10.2   5.6 |  21.3  70.3  185   8  4   9.0   5.0
  7500  21.6  70.9  190   7  3  10.0   5.5 |  21.9  71.4  185   8  4   9.5   5.2
  7250  22.3  72.1  190   7  4   9.8   5.4 |  22.7  72.9  185   8  4   9.6   5.3
  7000  23.1  73.6  195   7  4  10.4   5.7 |  23.4  74.1  185   8  4  10.1   5.5
  6750  23.9  75.0  195   7  4  10.6   5.8 |  24.2  75.6  185   8  4  10.9   6.0
  6500  24.6  76.3  195   7  4  10.2   5.6 |  25.0  77.0  185   8  4  10.6   5.8
  6250  25.4  77.7  195   7  4   9.9   5.4 |  25.7  78.3  185   8  4  10.8   5.9
  6000  26.1  79.0  200   7  4  10.9   6.0 |  26.5  79.7  190   8  4   9.3   5.1
  5750  27.1  80.8  200   7  4  15.5   8.5 |  27.2  81.0  190   8  4  11.1   6.1
  5500  28.4  83.1  200   7  4  20.1  11.1 |  28.2  82.8  190   7  4  18.5  10.1
________________________________________________________________________________

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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