Soaring Guidance
Issued by NWS Denver/Boulder, CO

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000
UXUS97 KBOU 140053
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
1853 MDT Sunday, May 13, 2018

This forecast is for Monday, May 14, 2018:

If the trigger temperature of 62.5 F/16.9 C is reached...then
   Thermal Soaring Index....................... Poor
   Maximum rate of lift........................ 20 ft/min (0.1 m/s)
   Maximum height of thermals.................. 10964 ft MSL (5657 ft AGL)

Forecast maximum temperature................... 66.0 F/19.3 C
Time of trigger temperature.................... 1115 MDT
Time of overdevelopment........................ 1500 MDT
Middle/high clouds during soaring window....... Broken/overcast opaque middle
Surface winds during soaring window............ 20 mph or less
Height of the -3 thermal index................. 8273 ft MSL (2966 ft AGL)
Thermal soaring outlook for Tuesday 05/15...... Good

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1800 MDT)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1800 MDT)................ Weak PVA
Potential height of wave....................... 39304 ft MSL (33997 ft AGL)
Wave soaring outlook for Tuesday 05/15......... Poor

Remarks...

***ATTENTION Soaring Forecast Users***The National Weather Service in Boulder wants to hear from you.
Please send and email to paul.t.schlatter@noaa.gov and let us know how you use the Soaring Forecast.  Thanks!

Sunrise/Sunset.................... 05:45:51 / 20:05:38 MDT
Total possible sunshine........... 14 hr 19 min 47 sec (859 min 47 sec)
Altitude of sun at 12:55:56 MDT... 68.97 degrees

Upper air data from numerical model forecast valid on 05/14/2018 at 0600 MDT

Freezing level.................. 12151 ft MSL (6844 ft AGL)
Convective condensation level... 9474 ft MSL (4167 ft AGL)
Lifted condensation level....... 10240 ft MSL (4933 ft AGL)
Lifted index.................... -3.3
K index......................... +21.7

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  -60.1 -76.2   240   37   19   1.9   1.1      M     M       M      M    M
 45000  -57.4 -71.3   230   49   25   0.9   0.5      M     M       M      M    M
 40000  -56.1 -69.0   215   60   31   1.0   0.5      M     M       M      M    M
 38000  -54.1 -65.4   210   63   32   4.0   2.2      M     M       M      M    M
 36000  -51.7 -61.1   210   65   33   4.0   2.2      M     M       M      M    M
 34000  -48.2 -54.8   210   64   33   6.8   3.8      M     M       M      M    M
 32000  -44.1 -47.4   215   61   31   6.9   3.8      M     M       M      M    M
 30000  -39.7 -39.5   215   56   29   7.7   4.2   35.9  96.7    12.9      M    M
 29000  -37.4 -35.3   215   53   28   7.7   4.2   35.1  95.2    12.4      M    M
 28000  -35.1 -31.2   215   51   26   7.8   4.3   34.4  94.0    12.0      M    M
 27000  -32.7 -26.9   215   48   25   8.0   4.4   33.7  92.7    11.6      M    M
 26000  -30.3 -22.5   215   46   24   8.0   4.4   33.0  91.4    11.2      M    M
 25000  -27.9 -18.2   215   44   23   8.0   4.4   32.4  90.3    10.8      M    M
 24000  -25.6 -14.1   215   42   22   6.9   3.8   31.7  89.1    10.4      M    M
 23000  -23.5 -10.3   220   40   21   7.0   3.8   30.6  87.1     9.6      M    M
 22000  -21.4  -6.5   220   38   19   7.0   3.8   29.7  85.4     8.9      M    M
 21000  -19.4  -2.9   220   35   18   6.7   3.7   28.7  83.6     8.1      M    M
 20000  -17.4   0.7   220   33   17   6.8   3.7   27.5  81.6     7.2      M    M
 19500  -16.4   2.5   225   32   17   6.8   3.7   27.0  80.6     6.8      M    M
 19000  -15.4   4.3   225   31   16   6.7   3.7   26.5  79.8     6.4      M    M
 18500  -14.4   6.1   225   30   16   7.6   4.2   26.1  79.0     6.0      M    M
 18000  -13.3   8.1   225   30   15   7.6   4.2   25.7  78.3     5.7      M    M
 17500  -11.5  11.3   230   28   14   9.0   4.9   25.3  77.5     5.3      M    M
 17000  -10.2  13.6   230   27   14   8.9   4.9   25.1  77.2     5.2      M    M
 16500   -8.9  16.0   230   25   13   8.9   4.9   25.0  76.9     5.0      M    M
 16000   -7.6  18.3   230   24   12   8.8   4.9   24.8  76.6     4.9      M    M
 15500   -6.2  20.8   235   22   11   8.7   4.8   24.7  76.4     4.9      M    M
 15000   -5.0  23.0   235   20   10   8.3   4.5   24.4  76.0     4.7      M    M
 14500   -3.8  25.2   235   18    9   8.3   4.6   24.2  75.5     4.4      M    M
 14000   -2.8  27.0   235   15    8   6.2   3.4   23.7  74.7     4.0      M    M
 13500   -1.9  28.6   230   12    6   6.8   3.7   23.2  73.8     3.4      M    M
 13000   -1.2  29.8   225   10    5   5.3   2.9   22.6  72.7     2.7      M    M
 12500   -0.4  31.3   225    8    4   5.3   2.9   21.9  71.4     2.0      M    M
 12000    0.3  32.5   220    6    3   6.0   3.3   21.2  70.2     1.3      M    M
 11500    1.2  34.2   205    5    3   6.0   3.3   20.6  69.1     0.6      M    M
 11000    2.0  35.6   190    4    2   5.6   3.1   20.0  68.0     0.0      M    M
 10500    2.8  37.0   180    3    2   6.0   3.3   19.3  66.8    -0.7    382  1.9
 10250    3.2  37.8   175    3    2   3.9   2.1   19.0  66.2    -1.0    363  1.8
 10000    3.4  38.1   165    3    1   5.7   3.1   18.5  65.3    -1.5    348  1.8
  9750    4.0  39.2   135    2    1   8.9   4.9   18.4  65.1    -1.6    323  1.6
  9500    4.6  40.3   105    3    2   8.6   4.7   18.3  64.9    -1.8    298  1.5
  9250    5.2  41.4   090    4    2   6.5   3.6   18.2  64.7    -1.9    273  1.4
  9000    5.5  41.9   080    5    3   5.4   3.0   17.8  64.1    -2.3    255  1.3
  8750    6.0  42.8   070    5    3   7.5   4.1   17.6  63.7    -2.6    233  1.2
  8500    6.5  43.7   065    6    3   7.3   4.0   17.4  63.3    -2.8    211  1.1
  8250    7.0  44.6   060    6    3   6.8   3.7   17.2  63.0    -3.0    188  1.0
  8000    7.5  45.5   055    6    3   5.9   3.2   17.0  62.5    -3.3    166  0.8
  7750    7.9  46.2   045    6    3   4.7   2.6   16.6  61.9    -3.6    146  0.7
  7500    8.3  46.9   040    6    3   3.8   2.1   16.2  61.1    -4.0    129  0.7
  7250    8.5  47.3   040    6    3   3.5   1.9   15.7  60.3    -4.4    113  0.6
  7000    8.8  47.8   035    5    3   3.2   1.7   15.2  59.4    -4.9     98  0.5
  6750    9.1  48.4   035    4    2   5.2   2.8   14.8  58.6    -5.4     83  0.4
  6500    9.5  49.1   035    4    2   5.7   3.1   14.5  58.1    -5.7     62  0.3
  6250    9.8  49.6   025    4    2   4.7   2.6   14.1  57.4    -6.1     44  0.2
  6000   10.2  50.4   010    5    3   4.7   2.6   13.8  56.8    -6.5     26  0.1
  5750   10.6  51.1   360    6    3   5.8   3.2   13.4  56.1    -6.9      8  0.0
  5500   11.1  52.0   355    5    3   8.6   4.7   13.2  55.8    -7.1      M    M

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

           05/14/2018 at 0900 MDT          |       05/14/2018 at 1200 MDT
                                           |
K index... +27.6  LI... -2.8               | K index... +24.3  LI... -4.2
CAPE... +501.6  CIN... -1.6                | CAPE... +910.8  CIN... 0.0
                                           |
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 -58.7 -73.7  240  34 17   2.3   1.3 | -58.9 -74.0  235  33 17   2.3   1.3
 45000 -55.5 -67.9  235  46 23   0.2   0.1 | -55.5 -67.9  240  43 22   1.7   0.9
 40000 -55.4 -67.7  220  63 32   0.2   0.1 | -53.0 -63.4  230  50 26   1.7   0.9
 38000 -54.0 -65.2  215  65 34   3.2   1.7 | -51.8 -61.2  225  51 26   2.1   1.1
 36000 -52.1 -61.8  215  65 34   3.2   1.7 | -50.5 -58.9  225  51 26   2.1   1.1
 34000 -49.2 -56.6  210  64 33   5.9   3.2 | -48.6 -55.5  225  50 26   4.2   2.3
 32000 -45.7 -50.3  210  59 30   5.9   3.2 | -46.1 -51.0  220  46 24   4.2   2.3
 30000 -41.5 -42.7  210  54 28   8.5   4.6 | -42.6 -44.7  220  41 21   8.2   4.5
 29000 -39.0 -38.2  210  50 26   8.4   4.6 | -40.1 -40.2  220  38 19   8.1   4.5
 28000 -36.4 -33.5  210  46 24   8.4   4.6 | -37.7 -35.9  215  35 18   8.1   4.5
 27000 -33.9 -29.0  210  43 22   7.9   4.4 | -35.2 -31.4  215  32 17   8.6   4.7
 26000 -31.6 -24.9  210  39 20   8.0   4.4 | -32.6 -26.7  210  31 16   8.6   4.7
 25000 -29.2 -20.6  210  35 18   8.0   4.4 | -30.0 -22.0  205  30 15   8.6   4.7
 24000 -26.8 -16.2  210  31 16   7.2   4.0 | -27.5 -17.5  205  29 15   7.8   4.3
 23000 -24.7 -12.5  210  30 16   7.3   4.0 | -25.1 -13.2  205  27 14   7.8   4.3
 22000 -22.5  -8.5  215  30 15   7.3   4.0 | -22.8  -9.0  210  25 13   7.8   4.3
 21000 -20.3  -4.5  220  29 15   7.8   4.3 | -20.5  -4.9  215  24 12   7.1   3.9
 20000 -18.1  -0.6  225  28 15   7.8   4.3 | -18.4  -1.1  220  23 12   7.1   3.9
 19500 -16.9   1.6  225  28 14   7.8   4.3 | -17.3   0.9  225  23 12   7.2   3.9
 19000 -15.8   3.6  225  27 14   7.8   4.3 | -16.3   2.7  230  23 12   7.1   3.9
 18500 -14.6   5.7  230  27 14   8.1   4.4 | -15.2   4.6  230  23 12   8.1   4.4
 18000 -13.4   7.9  230  26 13   8.1   4.4 | -14.0   6.8  235  23 12   8.1   4.5
 17500 -11.7  10.9  235  25 13   7.8   4.3 | -12.2  10.0  240  22 12   8.6   4.7
 17000 -10.5  13.1  235  24 12   7.8   4.3 | -10.9  12.4  240  22 11   8.6   4.7
 16500  -9.4  15.1  240  23 12   7.8   4.3 |  -9.7  14.5  240  22 11   8.8   4.9
 16000  -8.2  17.2  240  21 11   7.8   4.3 |  -8.4  16.9  245  21 11   8.9   4.9
 15500  -7.1  19.2  240  20 10   7.8   4.3 |  -7.1  19.2  245  21 11   8.6   4.7
 15000  -6.0  21.2  240  18  9   7.5   4.1 |  -5.9  21.4  245  20 10   7.8   4.3
 14500  -4.9  23.2  235  16  8   7.6   4.2 |  -4.8  23.4  245  19 10   7.9   4.3
 14000  -4.0  24.8  230  14  7   5.1   2.8 |  -3.6  25.5  245  19 10   8.0   4.4
 13500  -3.3  26.1  225  13  7   5.2   2.8 |  -2.5  27.5  240  18  9   8.2   4.5
 13000  -2.4  27.7  225  12  6   7.2   3.9 |  -1.4  29.5  240  18  9   6.2   3.4
 12500  -1.4  29.5  225  11  6   7.2   4.0 |  -0.6  30.9  235  18  9   6.5   3.6
 12000  -0.5  31.1  225  10  5   5.5   3.0 |   0.3  32.5  230  17  9   5.2   2.8
 11500   0.3  32.5  225   8  4   5.4   3.0 |   1.0  33.8  220  16  8   5.1   2.8
 11000   1.1  34.0  220   7  3   6.6   3.6 |   1.7  35.1  215  14  7   6.2   3.4
 10500   2.1  35.8  225   5  3   7.2   4.0 |   2.6  36.7  215  11  5   7.0   3.8
 10250   2.5  36.5  225   4  2   4.8   2.6 |   3.0  37.4  210   9  5   3.4   1.8
 10000   2.8  37.0  225   4  2   5.7   3.2 |   3.2  37.8  205   8  4   4.3   2.4
  9750   3.4  38.1  215   2  1   8.7   4.8 |   3.7  38.7  200   7  3   8.4   4.6
  9500   4.0  39.2  190   1  1   8.5   4.7 |   4.3  39.7  190   5  3   8.0   4.4
  9250   4.6  40.3  110   1  0   6.6   3.6 |   4.8  40.6  170   4  2   5.6   3.1
  9000   5.0  41.0  100   2  1   5.4   3.0 |   5.1  41.2  155   4  2   5.6   3.1
  8750   5.4  41.7  100   2  1   7.1   3.9 |   5.6  42.1  135   4  2   8.7   4.8
  8500   5.9  42.6  100   3  2   6.9   3.8 |   6.2  43.2  115   4  2   8.4   4.6
  8250   6.3  43.3  105   4  2   6.0   3.3 |   6.8  44.2  105   5  2   8.8   4.8
  8000   6.7  44.1  105   4  2   5.5   3.0 |   7.4  45.3  100   5  2   9.2   5.1
  7750   7.2  45.0  105   4  2   6.6   3.6 |   8.1  46.6  100   5  3  10.0   5.5
  7500   7.6  45.7  105   4  2   6.0   3.3 |   8.9  48.0  095   5  3  10.3   5.6
  7250   8.0  46.4  105   3  2   4.5   2.4 |   9.6  49.3  095   5  3  10.1   5.6
  7000   8.3  46.9  090   2  1   4.2   2.3 |  10.4  50.7  095   5  3  10.2   5.6
  6750   8.6  47.5  065   1  1   4.9   2.7 |  11.1  52.0  095   5  3   9.6   5.3
  6500   9.1  48.4  020   2  1   5.9   3.3 |  11.9  53.4  095   5  2  10.5   5.8
  6250   9.5  49.1  360   2  1   6.4   3.5 |  12.7  54.9  095   5  2  12.1   6.6
  6000  10.0  50.0  350   3  1   5.6   3.1 |  13.6  56.5  090   5  2  10.2   5.6
  5750  10.4  50.7  340   3  2   8.1   4.5 |  14.4  57.9  090   5  2  14.7   8.1
  5500  11.3  52.3  335   3  2  15.1   8.3 |  16.0  60.8  090   5  2  28.4  15.6

           05/14/2018 at 1500 MDT          |       05/14/2018 at 1800 MDT
                                           |
K index... +29.0  LI... -4.0               | K index... +26.7  LI... -0.6
CAPE... +988.6  CIN... 0.0                 | CAPE... +55.3  CIN... -76.8
                                           |
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 -58.9 -74.0  250  31 16   1.9   1.0 | -59.5 -75.1  260  31 16   1.8   1.0
 45000 -56.1 -69.0  255  40 21   1.7   0.9 | -57.1 -70.8  270  44 23   0.1   0.0
 40000 -53.6 -64.5  250  61 31   1.7   0.9 | -57.1 -70.8  265  55 28  -0.5  -0.3
 38000 -52.6 -62.7  255  63 33   1.6   0.9 | -54.2 -65.6  260  57 29   5.6   3.1
 36000 -51.6 -60.9  260  63 33   1.6   0.9 | -50.9 -59.6  260  59 30   5.6   3.1
 34000 -49.2 -56.6  265  60 31   6.8   3.7 | -47.2 -53.0  260  59 30   6.8   3.7
 32000 -45.1 -49.2  270  51 26   6.8   3.7 | -43.1 -45.6  260  56 29   6.8   3.7
 30000 -40.9 -41.6  270  45 23   7.7   4.2 | -39.1 -38.4  260  50 26   6.5   3.6
 29000 -38.6 -37.5  265  43 22   7.7   4.2 | -37.2 -35.0  260  46 24   6.5   3.6
 28000 -36.3 -33.3  260  41 21   7.7   4.2 | -34.7 -30.5  260  40 21   6.5   3.6
 27000 -34.0 -29.2  260  39 20   7.3   4.0 | -32.6 -26.7  260  37 19   7.6   4.2
 26000 -31.8 -25.2  255  36 19   7.3   4.0 | -30.3 -22.5  260  35 18   7.7   4.2
 25000 -29.6 -21.3  245  34 17   7.3   4.0 | -28.0 -18.4  255  32 17   7.7   4.2
 24000 -27.3 -17.1  240  32 16   8.6   4.7 | -25.7 -14.3  255  30 16   7.7   4.2
 23000 -24.7 -12.5  240  31 16   8.6   4.7 | -23.4 -10.1  260  29 15   7.7   4.2
 22000 -22.1  -7.8  240  30 15   8.6   4.7 | -21.1  -6.0  260  29 15   7.7   4.2
 21000 -19.7  -3.5  240  28 15   7.5   4.1 | -18.9  -2.0  255  28 14   7.7   4.2
 20000 -17.4   0.7  240  26 13   7.6   4.2 | -16.6   2.1  250  28 14   7.8   4.3
 19500 -16.3   2.7  235  24 12   7.6   4.2 | -15.5   4.1  245  28 14   7.9   4.3
 19000 -15.1   4.8  235  23 12   7.6   4.2 | -14.4   6.1  245  28 15   8.0   4.4
 18500 -14.0   6.8  235  22 11   7.6   4.2 | -13.2   8.2  240  29 15   7.9   4.3
 18000 -12.3   9.9  235  20 10   7.7   4.2 | -12.1  10.2  240  30 15   7.9   4.4
 17500 -11.2  11.8  230  20 10   7.7   4.2 | -10.9  12.4  235  31 16   8.4   4.6
 17000 -10.1  13.8  230  19 10   7.8   4.3 |  -9.7  14.5  235  30 15   8.6   4.7
 16500  -9.0  15.8  230  18  9   7.9   4.3 |  -8.5  16.7  230  29 15   8.6   4.7
 16000  -7.9  17.8  230  18  9   7.9   4.4 |  -7.3  18.9  230  27 14   7.9   4.3
 15500  -6.7  19.9  230  17  9   7.7   4.3 |  -6.1  21.0  225  26 13   8.1   4.4
 15000  -5.7  21.7  225  17  9   6.7   3.7 |  -4.6  23.7  225  22 12   7.0   3.8
 14500  -4.8  23.4  225  16  8   6.8   3.7 |  -3.6  25.5  225  20 10   6.9   3.8
 14000  -3.8  25.2  225  16  8   6.9   3.8 |  -2.7  27.1  225  18  9   5.7   3.1
 13500  -2.8  27.0  220  16  8   7.0   3.9 |  -1.9  28.6  230  16  8   5.9   3.2
 13000  -1.9  28.6  215  15  8   5.8   3.2 |  -1.1  30.0  235  14  7   4.8   2.6
 12500  -1.1  30.0  215  14  7   5.8   3.2 |  -0.4  31.3  240  12  6   4.9   2.7
 12000  -0.3  31.5  205  13  7   5.9   3.2 |   0.3  32.5  250  10  5   4.8   2.6
 11500   0.6  33.1  195  10  5   5.8   3.2 |   1.0  33.8  265   9  5   4.7   2.6
 11000   1.4  34.5  170   7  4   7.3   4.0 |   1.7  35.1  280   9  5   5.7   3.1
 10500   2.5  36.5  140   6  3   7.9   4.3 |   2.6  36.7  295  10  5   6.3   3.5
 10250   3.0  37.4  120   7  4   5.8   3.2 |   3.0  37.4  305  10  5   3.0   1.6
 10000   3.4  38.1  115   7  4   7.3   4.0 |   3.1  37.6  305  10  5   3.7   2.1
  9750   4.1  39.4  105   8  4  10.5   5.7 |   3.6  38.5  310  10  5   7.5   4.1
  9500   4.8  40.6  095   9  5  10.0   5.5 |   4.1  39.4  320  11  5   7.0   3.8
  9250   5.5  41.9  090  11  6   9.0   4.9 |   4.6  40.3  325  11  6   4.9   2.7
  9000   6.1  43.0  085  11  6   8.9   4.9 |   4.8  40.6  330  11  6   3.5   1.9
  8750   6.8  44.2  085  12  6  10.2   5.6 |   5.2  41.4  335  11  6   5.2   2.8
  8500   7.5  45.5  085  12  6   9.9   5.4 |   5.5  41.9  340  11  6   4.8   2.6
  8250   8.3  46.9  080  12  6  10.2   5.6 |   5.8  42.4  345  11  6   3.2   1.8
  8000   9.0  48.2  080  12  6  10.3   5.6 |   6.0  42.8  355  11  6   2.2   1.2
  7750   9.8  49.6  080  13  6  10.2   5.6 |   6.1  43.0  360  11  6   1.7   0.9
  7500  10.6  51.1  080  13  6  10.1   5.6 |   6.2  43.2  010  11  6   1.6   0.9
  7250  11.3  52.3  080  13  6   9.9   5.4 |   6.3  43.3  015  11  6   2.2   1.2
  7000  12.1  53.8  080  13  6   9.9   5.4 |   6.5  43.7  025  11  6   2.1   1.2
  6750  12.8  55.0  080  13  6   9.7   5.3 |   6.6  43.9  030  12  6   2.4   1.3
  6500  13.5  56.3  080  13  6  10.3   5.6 |   6.9  44.4  040  12  6   6.2   3.4
  6250  14.3  57.7  080  12  6  11.1   6.1 |   7.4  45.3  040  11  6   9.1   5.0
  6000  15.1  59.2  080  12  6  10.3   5.6 |   8.0  46.4  045  10  5   7.4   4.0
  5750  15.9  60.6  075  12  6  12.2   6.7 |   8.5  47.3  045   9  5  11.8   6.5
  5500  17.1  62.8  075  12  6  19.4  10.6 |   9.8  49.6  045   8  4  22.1  12.1
________________________________________________________________________________

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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