Soaring Guidance
Issued by NWS Denver/Boulder, CO

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Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0122 UTC Saturday, May 26, 2018

This forecast is for Saturday, May 26, 2018:

If the trigger temperature of 84.7 F/29.3 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1570 ft/min (8.0 m/s)
   Maximum height of thermals.................. 21324 ft MSL (16017 ft AGL)

Forecast maximum temperature................... 94.0 F/34.9 C
Time of trigger temperature.................... 1115 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................. 15381 ft MSL (10075 ft AGL)
Thermal soaring outlook for Sunday 05/27....... Poor

Wave Soaring Index............................. Poor
Wave Soaring Index trend (to 1700 MST)......... Little change
Height of stable layer (12-18K ft MSL)......... None
Weak PVA/NVA (through 1700 MST)................ Neither
Potential height of wave....................... 45342 ft MSL (40035 ft AGL)
Wave soaring outlook for Sunday 05/27.......... 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.................... 05:36:37 / 20:16:18 MST
Total possible sunshine........... 14 hr 39 min 41 sec (879 min 41 sec)
Altitude of sun at 12:56:40 MST... 71.43 degrees

Upper air data from numerical model forecast valid on 05/26/2018 at 0500 MST

Freezing level.................. 15783 ft MSL (10476 ft AGL)
Convective condensation level... 19910 ft MSL (14603 ft AGL)
Lifted condensation level....... 20378 ft MSL (15071 ft AGL)
Lifted index.................... -2.1
K index......................... +11.0

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  -61.7 -79.1   265   26   13   1.1   0.6      M     M       M      M    M
 45000  -60.3 -76.5   260   37   19   0.2   0.1      M     M       M      M    M
 40000  -59.8 -75.6   230   26   13   6.5   3.6      M     M       M      M    M
 38000  -55.2 -67.4   230   28   14   7.6   4.2      M     M       M      M    M
 36000  -50.6 -59.1   230   30   15   7.6   4.2      M     M       M      M    M
 34000  -46.0 -50.8   230   27   14   7.6   4.2      M     M       M      M    M
 32000  -41.4 -42.5   225   24   12   7.7   4.2      M     M       M      M    M
 30000  -36.3 -33.3   230   21   11   9.0   4.9   38.7 101.6     3.2      M    M
 29000  -33.0 -27.4   230   20   10   9.0   4.9   38.3 101.0     3.0      M    M
 28000  -30.3 -22.5   230   19   10   8.7   4.8   38.2 100.8     2.9      M    M
 27000  -27.8 -18.0   235   19   10   8.2   4.5   37.5  99.5     2.4      M    M
 26000  -25.3 -13.5   245   18    9   8.2   4.5   36.9  98.5     2.0      M    M
 25000  -22.9  -9.2   250   18    9   8.2   4.5   36.5  97.6     1.6      M    M
 24000  -20.4  -4.7   250   18    9   8.3   4.6   35.9  96.6     1.1      M    M
 23000  -17.9  -0.2   250   19   10   8.3   4.6   35.3  95.6     0.7      M    M
 22000  -15.4   4.3   250   19   10   8.3   4.6   34.9  94.9     0.3      M    M
 21000  -13.0   8.6   250   18    9   8.2   4.5   34.3  93.8    -0.2   1539  7.8
 20000  -10.5  13.1   245   17    9   8.3   4.5   33.8  92.8    -0.6   1436  7.3
 19500   -9.3  15.3   245   16    8   8.3   4.5   33.6  92.4    -0.9   1385  7.0
 19000   -8.1  17.4   240   16    8   8.1   4.4   33.3  92.0    -1.1   1334  6.8
 18500   -6.9  19.6   240   15    8   8.1   4.4   33.0  91.5    -1.4   1283  6.5
 18000   -5.7  21.7   240   14    7   8.1   4.4   32.8  91.0    -1.6   1233  6.3
 17500   -4.5  23.9   235   14    7   8.1   4.5   32.5  90.4    -1.9   1182  6.0
 17000   -3.3  26.1   235   14    7   8.1   4.5   32.2  89.9    -2.2   1132  5.7
 16500   -2.1  28.2   235   14    7   8.6   4.7   32.0  89.5    -2.5   1081  5.5
 16000   -0.8  30.6   235   14    7   8.7   4.8   31.8  89.2    -2.7   1028  5.2
 15500    0.4  32.7   235   14    7   8.7   4.8   31.6  88.9    -2.9    976  5.0
 15000    2.3  36.1   235   13    7   8.6   4.7   31.3  88.3    -3.2    897  4.6
 14500    3.6  38.5   235   12    6   9.1   5.0   31.1  88.1    -3.4    844  4.3
 14000    5.0  41.0   230   12    6   9.3   5.1   31.1  87.9    -3.5    787  4.0
 13500    6.4  43.5   230   11    6   9.3   5.1   31.0  87.8    -3.6    731  3.7
 13000    7.8  46.0   230   10    5   9.4   5.1   30.9  87.7    -3.7    675  3.4
 12500    9.1  48.4   230   10    5   9.3   5.1   30.9  87.6    -3.8    618  3.1
 12000   10.5  50.9   230   10    5   9.0   4.9   30.8  87.4    -3.9    563  2.9
 11500   11.8  53.2   225    9    5   9.0   4.9   30.7  87.2    -4.0    508  2.6
 11000   13.0  55.4   225    9    5   7.4   4.0   30.4  86.7    -4.3    458  2.3
 10500   14.1  57.4   225    9    5  10.4   5.7   30.0  86.0    -4.7    411  2.1
 10250   15.0  59.0   230    9    5  11.2   6.2   30.2  86.4    -4.5    376  1.9
 10000   15.6  60.1   230    9    5   7.8   4.3   30.1  86.2    -4.7    349  1.8
  9750   16.3  61.3   230    9    5   8.8   4.8   30.0  86.0    -4.8    323  1.6
  9500   16.9  62.4   235    9    5   8.4   4.6   29.9  85.9    -4.9    297  1.5
  9250   17.5  63.5   235    9    5   7.2   4.0   29.8  85.6    -5.0    272  1.4
  9000   18.0  64.4   235    9    5   7.9   4.3   29.6  85.2    -5.3    249  1.3
  8750   18.6  65.5   235   10    5   9.1   5.0   29.5  85.1    -5.4    222  1.1
  8500   19.3  66.7   240   10    5   8.6   4.7   29.4  85.0    -5.5    196  1.0
  8250   19.9  67.8   240   10    5   7.7   4.2   29.3  84.8    -5.6    170  0.9
  8000   20.4  68.7   240   11    6   6.8   3.7   29.1  84.4    -5.8    147  0.7
  7750   20.9  69.6   240   11    6   6.8   3.8   28.9  84.0    -6.0    124  0.6
  7500   21.4  70.5   240   11    6   6.4   3.5   28.7  83.6    -6.3    102  0.5
  7250   21.9  71.4   235   11    6   5.8   3.2   28.4  83.1    -6.6     82  0.4
  7000   22.2  72.0   235   12    6   4.5   2.5   28.0  82.5    -7.0     63  0.3
  6750   22.6  72.7   235   11    6   5.3   2.9   27.6  81.8    -7.4     46  0.2
  6500   22.8  73.0   235   11    6  -3.6  -2.0   27.1  80.8    -7.9     33  0.2
  6250   21.9  71.4   230   11    6 -13.7  -7.5   25.6  78.1    -9.5     50  0.3
  6000   20.9  69.6   230   11    5 -11.2  -6.2   23.9  75.0   -11.3     72  0.4
  5750   20.0  68.0   230   10    5 -17.2  -9.5   22.2  72.0   -13.0     95  0.5
  5500   17.8  64.0   230   10    5 -41.4 -22.7   19.4  66.9   -15.9    153  0.8

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

           05/26/2018 at 0800 MST          |       05/26/2018 at 1100 MST
                                           |
K index... +3.9  LI... +1.9                | K index... -16.9  LI... +1.6
CAPE... 0.0  CIN... 0.0                    | CAPE... +11.2  CIN... -39.4
                                           |
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 -61.2 -78.2  255  24 12   2.1   1.1 | -61.7 -79.1  250  21 11   2.0   1.1
 45000 -58.7 -73.7  260  38 20  -0.2  -0.1 | -59.3 -74.7  255  26 13  -0.1  -0.1
 40000 -58.9 -74.0  250  35 18   4.6   2.5 | -59.2 -74.6  240  43 22   5.5   3.0
 38000 -55.1 -67.2  240  33 17   6.4   3.5 | -55.0 -67.0  240  43 22   7.0   3.8
 36000 -51.2 -60.2  235  33 17   6.4   3.5 | -50.8 -59.4  235  44 23   7.0   3.8
 34000 -46.8 -52.2  230  31 16   7.8   4.3 | -46.4 -51.5  235  40 21   7.6   4.2
 32000 -42.1 -43.8  225  29 15   7.8   4.3 | -41.9 -43.4  235  34 18   7.6   4.2
 30000 -37.1 -34.8  225  27 14   8.9   4.9 | -36.8 -34.2  230  30 15   8.9   4.9
 29000 -33.7 -28.7  225  25 13   8.9   4.9 | -33.5 -28.3  225  28 14   8.9   4.9
 28000 -31.1 -24.0  225  24 12   8.7   4.8 | -30.9 -23.6  220  27 14   8.6   4.7
 27000 -28.5 -19.3  225  23 12   8.5   4.7 | -28.4 -19.1  215  26 13   8.3   4.6
 26000 -26.0 -14.8  225  21 11   8.5   4.7 | -25.9 -14.6  215  26 13   8.3   4.6
 25000 -23.4 -10.1  230  20 10   8.5   4.7 | -23.4 -10.1  210  26 13   8.3   4.5
 24000 -20.9  -5.6  230  19 10   8.7   4.8 | -20.8  -5.4  210  25 13   8.7   4.8
 23000 -18.2  -0.8  225  18 10   8.7   4.8 | -18.2  -0.8  210  25 13   8.7   4.8
 22000 -15.6   3.9  225  18  9   8.7   4.8 | -15.6   3.9  205  24 13   8.7   4.8
 21000 -13.2   8.2  220  18  9   8.2   4.5 | -13.1   8.4  205  25 13   8.3   4.6
 20000 -10.7  12.7  215  18  9   8.3   4.5 | -10.6  12.9  205  25 13   8.4   4.6
 19500  -9.5  14.9  215  18  9   8.3   4.5 |  -9.4  15.1  205  25 13   8.4   4.6
 19000  -8.3  17.1  210  18  9   8.2   4.5 |  -8.1  17.4  205  25 13   8.2   4.5
 18500  -7.0  19.4  210  18  9   8.2   4.5 |  -6.9  19.6  205  25 13   8.2   4.5
 18000  -5.8  21.6  205  18  9   8.3   4.5 |  -5.7  21.7  205  24 13   8.3   4.6
 17500  -4.6  23.7  205  18  9   8.6   4.7 |  -4.4  24.1  200  24 12   9.0   4.9
 17000  -3.3  26.1  205  18  9   8.6   4.7 |  -3.1  26.4  200  23 12   8.9   4.9
 16500  -2.0  28.4  205  18  9   8.3   4.6 |  -1.7  28.9  200  22 11   8.8   4.8
 16000  -0.8  30.6  200  18  9   8.4   4.6 |  -0.4  31.3  200  22 11   8.8   4.8
 15500   1.0  33.8  200  18  9   8.7   4.8 |   1.6  34.9  200  21 11   9.0   4.9
 15000   2.3  36.1  195  18  9   8.7   4.8 |   2.9  37.2  200  20 10   9.0   4.9
 14500   3.6  38.5  195  18  9   9.0   4.9 |   4.3  39.7  200  19 10   8.6   4.7
 14000   4.9  40.8  195  17  9   9.1   5.0 |   5.5  41.9  205  19 10   8.5   4.6
 13500   6.3  43.3  200  16  8   9.1   5.0 |   6.8  44.2  205  18  9   8.8   4.8
 13000   7.6  45.7  200  15  8   9.0   4.9 |   8.2  46.8  210  17  9   9.3   5.1
 12500   9.0  48.2  205  14  7   9.0   4.9 |   9.6  49.3  210  17  9   9.2   5.0
 12000  10.4  50.7  210  13  7   9.2   5.1 |  10.8  51.4  210  17  9   8.3   4.5
 11500  11.7  53.1  210  12  6   9.2   5.0 |  12.1  53.8  215  16  8   8.3   4.6
 11000  12.9  55.2  215  11  6   7.6   4.2 |  13.2  55.8  215  15  8   7.0   3.8
 10500  14.1  57.4  220  10  5  10.1   5.5 |  14.2  57.6  210  14  7   9.0   4.9
 10250  14.9  58.8  220   9  4  10.8   5.9 |  15.0  59.0  205  13  7  10.0   5.5
 10000  15.6  60.1  225   8  4   8.0   4.4 |  15.6  60.1  205  12  6   8.2   4.5
  9750  16.2  61.2  225   7  4   8.8   4.8 |  16.2  61.2  200  10  5   8.8   4.8
  9500  16.8  62.2  230   6  3   8.4   4.6 |  16.8  62.2  195   9  5   8.6   4.7
  9250  17.4  63.3  230   5  3   7.2   3.9 |  17.4  63.3  190   8  4   8.6   4.7
  9000  17.9  64.2  235   5  2   7.6   4.2 |  18.0  64.4  185   7  4   9.1   5.0
  8750  18.5  65.3  245   4  2   8.7   4.8 |  18.7  65.7  180   6  3   9.5   5.2
  8500  19.1  66.4  255   3  2   8.3   4.5 |  19.3  66.7  175   5  3   9.6   5.3
  8250  19.7  67.5  270   3  2   7.3   4.0 |  20.0  68.0  170   5  3  10.4   5.7
  8000  20.2  68.4  285   3  2   6.8   3.7 |  20.8  69.4  165   5  2  10.1   5.6
  7750  20.7  69.3  295   3  2   7.2   3.9 |  21.5  70.7  165   5  2   9.4   5.1
  7500  21.2  70.2  305   4  2   6.6   3.6 |  22.2  72.0  165   4  2   9.8   5.4
  7250  21.7  71.1  310   4  2   5.7   3.1 |  23.0  73.4  165   4  2  10.4   5.7
  7000  22.1  71.8  305   4  2   5.0   2.8 |  23.7  74.7  165   4  2  10.4   5.7
  6750  22.5  72.5  305   4  2   6.2   3.4 |  24.5  76.1  165   4  2   9.7   5.3
  6500  22.8  73.0  300   4  2   1.3   0.7 |  25.2  77.4  165   4  2  10.2   5.6
  6250  22.6  72.7  290   4  2  -3.6  -2.0 |  26.0  78.8  165   4  2  11.1   6.1
  6000  22.3  72.1  280   4  2  -3.5  -1.9 |  26.8  80.2  160   3  2  10.6   5.8
  5750  22.0  71.6  265   4  2  -1.9  -1.1 |  27.6  81.7  160   3  2  12.1   6.6
  5500  22.0  71.6  245   3  2  10.2   5.6 |  28.8  83.8  160   3  2  20.7  11.4

           05/26/2018 at 1400 MST          |       05/26/2018 at 1700 MST
                                           |
K index... +3.4  LI... +0.7                | K index... +9.9  LI... +0.1
CAPE... +0.1  CIN... -0.4                  | CAPE... +22.7  CIN... -19.4
                                           |
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 -60.6 -77.1  250  28 14   2.3   1.2 | -60.2 -76.4  245  31 16   1.8   1.0
 45000 -57.9 -72.2  255  38 20  -0.6  -0.3 | -58.0 -72.4  245  49 25  -0.4  -0.2
 40000 -58.7 -73.7  255  57 29   5.3   2.9 | -58.4 -73.1  250  78 40   5.1   2.8
 38000 -54.5 -66.1  250  58 30   7.0   3.8 | -54.2 -65.6  245  68 35   7.1   3.9
 36000 -50.3 -58.5  245  59 31   7.0   3.8 | -49.9 -57.8  240  58 30   7.1   3.9
 34000 -45.9 -50.6  245  50 26   7.4   4.0 | -45.4 -49.7  235  46 23   7.9   4.3
 32000 -41.5 -42.7  240  36 19   7.4   4.0 | -40.6 -41.1  230  32 16   7.9   4.3
 30000 -36.0 -32.8  230  29 15   8.7   4.8 | -35.4 -31.7  220  25 13   7.6   4.2
 29000 -33.4 -28.1  225  28 15   8.7   4.8 | -33.1 -27.6  215  25 13   7.6   4.2
 28000 -30.8 -23.4  225  28 14   8.5   4.7 | -30.8 -23.4  210  25 13   7.7   4.2
 27000 -28.3 -18.9  225  27 14   8.1   4.4 | -28.5 -19.3  210  24 12   7.8   4.3
 26000 -25.9 -14.6  220  27 14   8.1   4.4 | -26.2 -15.2  205  22 12   7.8   4.3
 25000 -23.5 -10.3  220  27 14   8.1   4.4 | -23.8 -10.8  205  21 11   7.8   4.3
 24000 -21.0  -5.8  220  27 14   8.5   4.6 | -21.4  -6.5  205  22 11   8.5   4.7
 23000 -18.4  -1.1  220  28 14   8.5   4.6 | -18.8  -1.8  210  23 12   8.5   4.7
 22000 -15.9   3.4  220  28 14   8.5   4.6 | -16.3   2.7  210  25 13   8.5   4.6
 21000 -13.3   8.1  215  27 14   8.8   4.8 | -13.7   7.3  210  24 12   8.9   4.9
 20000 -10.7  12.7  210  27 14   8.8   4.8 | -11.1  12.0  205  23 12   8.9   4.9
 19500  -9.4  15.1  210  26 14   8.8   4.8 |  -9.8  14.4  205  22 11   8.9   4.9
 19000  -8.1  17.4  205  26 13   8.6   4.7 |  -8.4  16.9  200  22 11   9.3   5.1
 18500  -6.8  19.8  200  25 13   8.5   4.7 |  -7.0  19.4  200  21 11   9.5   5.2
 18000  -5.6  21.9  200  24 12   8.6   4.7 |  -5.6  21.9  200  21 11   9.5   5.2
 17500  -4.2  24.4  195  23 12   9.1   5.0 |  -4.2  24.4  200  20 11  10.1   5.5
 17000  -2.9  26.8  190  22 11   9.1   5.0 |  -2.7  27.1  195  20 10  10.1   5.5
 16500  -1.6  29.1  190  21 11   9.2   5.0 |  -1.2  29.8  195  20 10   9.7   5.3
 16000  -0.2  31.6  185  20 10   9.2   5.0 |   1.0  33.8  190  20 10   9.6   5.2
 15500   1.8  35.2  185  19 10   9.4   5.1 |   2.4  36.3  190  20 10   9.4   5.1
 15000   3.2  37.8  180  19 10   9.4   5.2 |   3.8  38.8  185  21 11   9.4   5.1
 14500   4.6  40.3  180  19 10   9.5   5.2 |   5.2  41.4  185  21 11   9.3   5.1
 14000   6.0  42.8  180  18  9   9.5   5.2 |   6.6  43.9  185  22 11   9.3   5.1
 13500   7.5  45.5  180  17  9   9.5   5.2 |   8.0  46.4  185  23 12   9.3   5.1
 13000   8.9  48.0  175  17  9   9.4   5.2 |   9.4  48.9  180  24 12   9.7   5.3
 12500  10.2  50.4  175  16  8   9.4   5.2 |  10.8  51.4  180  25 13   9.7   5.3
 12000  11.7  53.1  175  15  8   9.5   5.2 |  12.2  54.0  180  25 13   9.3   5.1
 11500  13.1  55.6  175  14  7   9.6   5.2 |  13.6  56.5  180  26 13   9.4   5.2
 11000  14.4  57.9  175  13  7   8.8   4.8 |  14.9  58.8  180  26 14   8.2   4.5
 10500  15.7  60.3  175  12  6  11.4   6.3 |  16.1  61.0  180  26 14   9.5   5.2
 10250  16.7  62.1  180  12  6  11.9   6.6 |  16.9  62.4  180  26 14  11.0   6.1
 10000  17.4  63.3  180  12  6   8.7   4.8 |  17.7  63.9  180  26 14  10.1   5.5
  9750  18.1  64.6  180  11  6   9.6   5.2 |  18.4  65.1  180  26 13  10.0   5.5
  9500  18.8  65.8  180  11  6   9.2   5.0 |  19.2  66.6  180  26 13  10.1   5.5
  9250  19.5  67.1  180  11  6   9.9   5.4 |  19.9  67.8  180  26 13   9.8   5.4
  9000  20.3  68.5  180  11  6  10.1   5.6 |  20.6  69.1  180  26 13   9.5   5.2
  8750  21.0  69.8  180  11  5   9.8   5.4 |  21.4  70.5  180  26 13   9.8   5.4
  8500  21.7  71.1  180  10  5   9.7   5.3 |  22.1  71.8  180  26 13   9.3   5.1
  8250  22.5  72.5  185  10  5  10.7   5.8 |  22.8  73.0  180  26 13  11.0   6.0
  8000  23.3  73.9  185  10  5  10.4   5.7 |  23.7  74.7  180  25 13  10.7   5.9
  7750  24.0  75.2  185  10  5   9.3   5.1 |  24.4  75.9  180  25 13   8.9   4.9
  7500  24.7  76.5  185  10  5   9.6   5.3 |  25.0  77.0  180  25 13   9.2   5.0
  7250  25.4  77.7  185   9  5  10.4   5.7 |  25.7  78.3  180  25 13  10.0   5.5
  7000  26.3  79.3  185   9  5  10.5   5.8 |  26.5  79.7  180  25 13  10.5   5.8
  6750  27.0  80.6  190   9  5   9.5   5.2 |  27.3  81.1  180  24 13   9.7   5.3
  6500  27.7  81.9  190   9  5   9.8   5.4 |  28.0  82.4  180  24 12   9.8   5.3
  6250  28.5  83.3  190   9  4  10.7   5.9 |  28.7  83.7  180  23 12  10.6   5.8
  6000  29.3  84.7  190   8  4  11.4   6.2 |  29.6  85.3  180  22 11  11.1   6.1
  5750  30.1  86.2  190   8  4   9.6   5.3 |  30.4  86.7  180  21 11  10.2   5.6
  5500  30.9  87.6  195   7  4  14.7   8.1 |  31.1  88.0  180  19 10  10.6   5.8
________________________________________________________________________________

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.

CINH (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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