Soaring Guidance
Issued by NWS Denver/Boulder, CO

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417
UXUS97 KBOU 241313
SRGBOU

Soaring Forecast
National Weather Service Denver/Boulder, Colorado
0713 MDT Thursday, May 24, 2018

This forecast is for Thursday, May 24, 2018:

If the trigger temperature of 73.8 F/23.2 C is reached...then
   Thermal Soaring Index....................... Excellent
   Maximum rate of lift........................ 1366 ft/min (6.9 m/s)
   Maximum height of thermals.................. 19709 ft MSL (14424 ft AGL)

Forecast maximum temperature................... 84.0 F/29.3 C
Time of trigger temperature.................... 1030 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................. 13655 ft MSL (8370 ft AGL)
Thermal soaring outlook for Friday 05/25....... Excellent

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)................ Weak NVA
Potential height of wave....................... 19050 ft MSL (13765 ft AGL)
Wave soaring outlook for Friday 05/25.......... Fair

Remarks... Warm, dry and slightly unstable airmass in place. Light to moderate
           westerly flow aloft.

***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.................... 05:37:29 / 20:15:13 MDT
Total possible sunshine........... 14 hr 37 min 45 sec (877 min 45 sec)
Altitude of sun at 12:56:21 MDT... 71.08 degrees

Upper air data from rawinsonde observation taken on 05/24/2018 at 0600 MDT

Freezing level.................. 13844 ft MSL (8559 ft AGL)
Convective condensation level... 14688 ft MSL (9403 ft AGL)
Lifted condensation level....... 16010 ft MSL (10725 ft AGL)
Lifted index.................... -4.4
K index......................... +16.2

Height  Temperature  Wind  Wind Spd  Lapse Rate  ConvectionT  Thermal  Lift Rate
ft MSL  deg C deg F   Dir   kt  m/s  C/km F/kft  deg C deg F   Index    fpm  m/s
--------------------------------------------------------------------------------
 50000  -58.6 -73.5   260   16    8  -0.6  -0.3   98.3 209.0    40.1      M    M
 45000  -59.7 -75.5   245   32   17  -1.8  -1.0   72.0 161.6    26.7      M    M
 40000  -55.5 -67.9   230   44   23   3.0   1.6   54.7 130.4    17.1      M    M
 38000  -54.2 -65.6   215   51   26   3.6   2.0   48.1 118.6    13.1      M    M
 36000  -50.2 -58.4   220   53   27   6.7   3.7   45.4 113.6    11.5      M    M
 34000  -46.3 -51.3   220   48   25   6.2   3.4   42.6 108.6     9.8      M    M
 32000  -41.6 -42.9   215   43   22   8.1   4.5   41.0 105.8     8.9      M    M
 30000  -36.5 -33.7   215   40   21   8.6   4.7   40.0 104.0     8.4      M    M
 29000  -33.3 -27.9   220   36   18   8.2   4.5   39.4 102.9     8.1      M    M
 28000  -31.9 -25.4   225   32   16   4.0   2.2   37.4  99.4     6.7      M    M
 27000  -30.4 -22.7   230   29   15   8.6   4.7   35.6  96.2     5.3      M    M
 26000  -27.8 -18.0   235   25   13   8.5   4.7   35.1  95.2     5.0      M    M
 25000  -25.3 -13.5   245   23   12   9.0   4.9   34.7  94.5     4.7      M    M
 24000  -23.4 -10.1   245   24   12   7.2   4.0   33.4  92.0     3.6      M    M
 23000  -21.3  -6.3   250   25   13   7.0   3.9   32.3  90.1     2.8      M    M
 22000  -19.2  -2.6   250   25   13   7.0   3.9   31.3  88.4     2.0      M    M
 21000  -17.1   1.2   255   26   13   7.1   3.9   30.5  86.9     1.3      M    M
 20000  -15.0   5.0   250   31   16   6.1   3.3   29.5  85.1     0.5      M    M
 19500  -14.3   6.3   245   35   18   5.6   3.1   28.7  83.7    -0.2   1353  6.9
 19000  -13.5   7.7   245   39   20   5.7   3.1   28.0  82.4    -0.9   1315  6.7
 18500  -12.4   9.7   245   37   19   8.3   4.6   27.5  81.6    -1.3   1268  6.4
 18000  -11.2  11.8   250   34   17   8.3   4.5   27.2  81.0    -1.6   1217  6.2
 17500  -10.1  13.8   250   31   16   5.9   3.2   26.8  80.3    -2.0   1170  5.9
 17000   -9.1  15.6   255   29   15   8.8   4.9   26.4  79.5    -2.4   1125  5.7
 16500   -7.7  18.1   260   27   14   9.3   5.1   26.3  79.4    -2.5   1069  5.4
 16000   -6.4  20.5   265   24   13   9.3   5.1   26.3  79.3    -2.5   1012  5.1
 15500   -5.0  23.0   265   23   12   9.3   5.1   26.2  79.2    -2.6    956  4.9
 15000   -3.6  25.5   260   22   11   9.3   5.1   26.1  79.0    -2.7    900  4.6
 14500   -1.5  29.3   255   20   10   9.3   5.1   26.1  78.9    -2.9    815  4.1
 14000   -0.1  31.8   255   19   10   9.3   5.1   26.0  78.8    -2.9    759  3.9
 13500    1.3  34.3   255   17    9   9.4   5.1   25.9  78.6    -3.1    703  3.6
 13000    2.6  36.7   250   15    8   9.4   5.1   25.8  78.5    -3.2    647  3.3
 12500    4.0  39.2   250   13    7   9.4   5.2   25.7  78.3    -3.3    590  3.0
 12000    5.3  41.5   245   12    6   8.0   4.4   25.6  78.0    -3.5    537  2.7
 11500    6.5  43.7   260   10    5   8.1   4.5   25.3  77.6    -3.8    487  2.5
 11000    7.7  45.9   275    9    4   8.4   4.6   25.1  77.1    -4.0    436  2.2
 10500    8.6  47.5   280    6    3   6.1   3.3   24.6  76.4    -4.6    393  2.0
 10250    9.0  48.2   295    4    2   7.8   4.3   24.4  76.0    -5.0    374  1.9
 10000    9.6  49.3   345    2    1   8.5   4.7   24.3  75.8    -5.2    351  1.8
  9750   10.1  50.2   005    3    1   8.3   4.5   24.2  75.6    -5.3    326  1.7
  9500   10.8  51.4   015    3    2   8.2   4.5   24.1  75.3    -5.4    299  1.5
  9250   11.5  52.7   020    4    2   8.4   4.6   24.0  75.1    -5.4    271  1.4
  9000   12.2  54.0   025    5    3   7.9   4.3   23.9  75.0    -5.5    243  1.2
  8750   12.6  54.7   020    6    3   4.4   2.4   23.6  74.5    -5.8    222  1.1
  8500   12.7  54.9   015    6    3   2.6   1.4   23.1  73.5    -6.5    212  1.1
  8250   12.8  55.0   015    6    3   3.6   2.0   22.6  72.6    -7.1    203  1.0
  8000   12.9  55.2   010    7    4   3.6   2.0   22.1  71.8    -7.7    192  1.0
  7750   13.2  55.8   010    7    3   3.6   2.0   21.6  70.9    -8.2    176  0.9
  7500   13.5  56.3   010    6    3   3.6   2.0   21.2  70.1    -8.7    160  0.8
  7250   13.7  56.7   005    6    3   3.6   2.0   20.7  69.3    -9.1    144  0.7
  7000   14.0  57.2   005    6    3   3.6   2.0   20.3  68.5    -9.6    128  0.7
  6750   14.3  57.7   360    6    3   3.7   2.0   19.8  67.6   -10.1    112  0.6
  6500   14.6  58.3   355    7    4   3.6   2.0   19.3  66.8   -10.5     97  0.5
  6250   14.9  58.8   355    7    4   3.8   2.1   18.9  66.0   -11.0     81  0.4
  6000   15.1  59.2   350    8    4   2.9   1.6   18.4  65.2   -11.5     65  0.3
  5750   15.4  59.7   350    6    3   6.4   3.5   18.0  64.3   -12.0     49  0.2
  5500   15.7  60.3   355    4    2  -6.6  -3.6   17.5  63.5   -12.4     33  0.2

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

           05/24/2018 at 0900 MDT          |       05/24/2018 at 1200 MDT
                                           |
CAPE...   +29.9    LI...       -0.4        | CAPE...   +95.7    LI...       -0.1
CINH...   -76.1    K Index... +15.5        | CINH...   -23.9    K Index... +17.1
                                           |
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 -60.7 -77.3  245  11  5   1.4   0.8 | -60.7 -77.3  260  13  7   0.5   0.3
 45000 -58.3 -72.9  255  15  8   2.5   1.4 | -59.2 -74.6  265  19 10   3.4   1.9
 40000 -54.6 -66.3  245  23 12   2.6   1.4 | -54.1 -65.4  265  27 14   3.6   2.0
 38000 -51.5 -60.7  240  22 11   4.7   2.6 | -50.8 -59.4  260  26 13   4.9   2.7
 36000 -48.7 -55.7  230  21 11   4.7   2.6 | -47.9 -54.2  255  25 13   4.9   2.7
 34000 -45.3 -49.5  230  21 11   6.2   3.4 | -44.8 -48.6  250  24 12   5.2   2.9
 32000 -41.6 -42.9  230  20 10   6.2   3.4 | -41.6 -42.9  245  23 12   5.2   2.9
 30000 -37.5 -35.5  230  19 10   7.2   3.9 | -37.9 -36.2  240  21 11   7.0   3.8
 29000 -35.4 -31.7  235  18  9   7.2   3.9 | -35.8 -32.4  240  20 10   7.0   3.8
 28000 -33.2 -27.8  235  17  9   7.2   3.9 | -33.7 -28.7  240  19 10   6.9   3.8
 27000 -31.0 -23.8  235  16  8   7.6   4.2 | -31.4 -24.5  240  17  9   7.8   4.3
 26000 -28.7 -19.7  240  15  8   7.6   4.2 | -29.1 -20.4  245  16  8   7.8   4.3
 25000 -26.4 -15.5  240  14  7   7.6   4.2 | -26.7 -16.1  245  15  8   7.8   4.3
 24000 -24.2 -11.6  240  13  6   7.3   4.0 | -24.4 -11.9  245  14  7   7.9   4.3
 23000 -22.0  -7.6  240  12  6   7.3   4.0 | -22.0  -7.6  245  13  7   7.9   4.3
 22000 -19.8  -3.6  240  11  6   7.3   4.0 | -19.7  -3.5  245  13  6   7.9   4.3
 21000 -17.7   0.1  240  11  5   7.0   3.9 | -16.8   1.8  245  12  6   7.6   4.2
 20000 -15.1   4.8  245  10  5   7.0   3.9 | -14.5   5.9  250  11  6   7.6   4.2
 19500 -14.0   6.8  245  10  5   7.0   3.9 | -13.4   7.9  250  10  5   7.7   4.2
 19000 -13.0   8.6  245  10  5   7.2   3.9 | -12.3   9.9  250  10  5   7.2   3.9
 18500 -11.9  10.6  245  10  5   7.2   4.0 | -11.2  11.8  250  10  5   7.2   4.0
 18000 -10.9  12.4  245  10  5   7.6   4.2 | -10.1  13.8  250  10  5   7.4   4.1
 17500  -9.7  14.5  245  10  5   8.3   4.6 |  -9.0  15.8  250  10  5   7.7   4.2
 17000  -8.4  16.9  245  10  5   8.3   4.5 |  -7.9  17.8  250   9  5   7.7   4.2
 16500  -7.2  19.0  245   9  5   8.9   4.9 |  -6.7  19.9  250   9  5   8.3   4.6
 16000  -5.9  21.4  245   9  5   8.8   4.8 |  -5.5  22.1  250   9  4   8.3   4.5
 15500  -4.6  23.7  245   8  4   8.8   4.8 |  -4.3  24.3  250   8  4   8.7   4.7
 15000  -3.3  26.1  245   8  4   8.8   4.8 |  -3.0  26.6  250   8  4   8.7   4.8
 14500  -1.9  28.6  245   8  4   8.9   4.9 |  -1.7  28.9  250   7  4   8.8   4.8
 14000  -0.6  30.9  245   7  4   9.0   4.9 |  -0.4  31.3  250   7  4   8.9   4.9
 13500   0.7  33.3  245   7  3   9.0   4.9 |   1.0  33.8  250   7  3   9.0   4.9
 13000   2.0  35.6  245   6  3   9.0   4.9 |   2.3  36.1  250   6  3   9.0   5.0
 12500   3.4  38.1  245   6  3   9.0   4.9 |   3.6  38.5  250   6  3   9.0   5.0
 12000   4.7  40.5  245   5  3   8.7   4.8 |   5.0  41.0  255   5  3   9.0   4.9
 11500   6.0  42.8  240   5  3   8.7   4.8 |   6.3  43.3  255   4  2   9.0   5.0
 11000   7.2  45.0  245   5  2   8.8   4.8 |   7.7  45.9  260   4  2   9.3   5.1
 10500   8.5  47.3  245   4  2   9.3   5.1 |   9.0  48.2  260   3  1  10.1   5.6
 10250   9.3  48.7  245   4  2   9.7   5.3 |   9.8  49.6  260   2  1  10.1   5.6
 10000   9.9  49.8  250   4  2   8.2   4.5 |  10.4  50.7  265   2  1   8.6   4.7
  9750  10.5  50.9  250   3  2   7.4   4.1 |  11.1  52.0  265   2  1   8.6   4.7
  9500  11.0  51.8  255   3  2   7.6   4.2 |  11.7  53.1  265   2  1   8.7   4.8
  9250  11.6  52.9  260   3  2   7.7   4.2 |  12.4  54.3  270   1  1   9.0   4.9
  9000  12.2  54.0  260   3  2   7.7   4.2 |  13.0  55.4  275   1  1   9.7   5.3
  8750  12.7  54.9  265   3  1   7.6   4.2 |  13.8  56.8  275   1  0  10.0   5.5
  8500  13.2  55.8  270   2  1   7.7   4.2 |  14.5  58.1  280   1  0  10.1   5.5
  8250  13.8  56.8  275   2  1   7.9   4.4 |  15.3  59.5  290   1  0  10.7   5.9
  8000  14.3  57.7  275   2  1   7.3   4.0 |  16.1  61.0  300   1  0  10.3   5.6
  7750  14.8  58.6  280   2  1   6.1   3.4 |  16.8  62.2  000   0  0   9.3   5.1
  7500  15.2  59.4  290   2  1   5.8   3.2 |  17.5  63.5  000   0  0   9.9   5.4
  7250  15.7  60.3  295   2  1   5.8   3.2 |  18.3  64.9  000   0  0  10.7   5.9
  7000  16.1  61.0  295   2  1   5.8   3.2 |  19.1  66.4  000   0  0  10.2   5.6
  6750  16.5  61.7  295   2  1   5.6   3.1 |  19.8  67.6  000   0  0   9.3   5.1
  6500  16.9  62.4  295   2  1   5.9   3.2 |  20.5  68.9  000   0  0   9.6   5.3
  6250  17.4  63.3  290   1  1   6.5   3.6 |  21.3  70.3  005   1  0  10.7   5.9
  6000  17.8  64.0  285   1  1   5.5   3.0 |  22.0  71.6  015   1  0   9.2   5.1
  5750  18.3  64.9  280   1  1   9.8   5.4 |  22.8  73.0  020   1  0  14.9   8.2
  5500  19.4  66.9  280   1  0  20.0  11.0 |  24.4  75.9  020   1  0  28.6  15.7

           05/24/2018 at 1500 MDT          |       05/24/2018 at 1800 MDT
                                           |
CAPE...  +118.1    LI...       -0.5        | CAPE...  +124.3    LI...       -0.5
CINH...   -17.1    K Index... +22.8        | CINH...   -32.1    K Index... +23.4
                                           |
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 -61.3 -78.3  265  14  7   0.1   0.0 | -61.8 -79.2  270  14  7   0.6   0.3
 45000 -59.9 -75.8  275  21 11   3.7   2.1 | -59.8 -75.6  270  19 10   3.4   1.9
 40000 -54.3 -65.7  270  26 14   5.2   2.9 | -54.6 -66.3  270  22 11   5.3   2.9
 38000 -50.8 -59.4  270  27 14   5.9   3.2 | -51.1 -60.0  275  23 12   5.8   3.2
 36000 -47.2 -53.0  270  27 14   5.9   3.2 | -47.6 -53.7  275  23 12   5.8   3.2
 34000 -43.8 -46.8  270  26 13   5.7   3.1 | -44.0 -47.2  280  22 11   6.2   3.4
 32000 -40.4 -40.7  270  24 12   5.7   3.1 | -39.8 -39.6  285  20 10   6.2   3.4
 30000 -36.4 -33.5  270  22 11   6.0   3.3 | -36.0 -32.8  290  17  9   6.6   3.6
 29000 -34.6 -30.3  265  21 11   6.0   3.3 | -34.0 -29.2  290  15  8   6.6   3.6
 28000 -32.8 -27.0  265  20 10   6.0   3.3 | -32.0 -25.6  295  14  7   6.6   3.6
 27000 -30.8 -23.4  265  19 10   6.9   3.8 | -29.9 -21.8  290  13  7   7.4   4.1
 26000 -28.7 -19.7  260  18  9   6.9   3.8 | -27.7 -17.9  285  12  6   7.4   4.1
 25000 -26.7 -16.1  260  18  9   6.9   3.8 | -25.5 -13.9  285  12  6   7.4   4.1
 24000 -24.4 -11.9  260  17  9   8.0   4.4 | -23.2  -9.8  275  12  6   7.6   4.2
 23000 -22.1  -7.8  255  16  8   8.1   4.4 | -21.0  -5.8  265  12  6   7.7   4.2
 22000 -19.7  -3.5  255  15  8   8.1   4.4 | -18.7  -1.7  260  12  6   7.7   4.2
 21000 -17.3   0.9  250  13  7   8.3   4.5 | -16.3   2.7  255  12  6   8.3   4.6
 20000 -14.8   5.4  250  12  6   8.3   4.5 | -13.9   7.0  255  10  5   8.4   4.6
 19500 -13.6   7.5  245  11  6   8.3   4.6 | -12.7   9.1  255  10  5   8.4   4.6
 19000 -12.4   9.7  245  10  5   8.0   4.4 | -11.5  11.3  255   9  5   7.8   4.3
 18500 -11.3  11.7  245  10  5   7.9   4.3 | -10.4  13.3  260   9  4   7.5   4.1
 18000 -10.1  13.8  245   9  5   7.9   4.3 |  -9.3  15.3  260   8  4   7.5   4.1
 17500  -8.4  16.9  240   8  4   7.8   4.3 |  -7.6  18.3  260   7  4   7.9   4.3
 17000  -7.2  19.0  240   8  4   8.0   4.4 |  -6.4  20.5  260   6  3   8.1   4.4
 16500  -6.0  21.2  240   7  4   9.1   5.0 |  -5.1  22.8  260   6  3   9.0   4.9
 16000  -4.6  23.7  240   7  3   9.0   5.0 |  -3.8  25.2  260   5  3   8.9   4.9
 15500  -3.2  26.2  235   6  3   9.4   5.2 |  -2.5  27.5  255   5  2   9.1   5.0
 15000  -1.8  28.8  235   6  3   9.4   5.2 |  -1.1  30.0  255   4  2   9.1   5.0
 14500  -0.4  31.3  235   5  3   9.5   5.2 |   0.2  32.4  250   4  2   9.3   5.1
 14000   1.0  33.8  235   5  2   9.6   5.2 |   1.6  34.9  250   4  2   9.4   5.2
 13500   2.4  36.3  235   4  2   9.5   5.2 |   3.0  37.4  245   3  2   9.4   5.2
 13000   3.8  38.8  230   4  2   9.5   5.2 |   4.4  39.9  240   3  2   9.4   5.2
 12500   5.2  41.4  230   3  2   9.5   5.2 |   5.8  42.4  240   3  1   9.4   5.2
 12000   6.7  44.1  230   3  2   9.5   5.2 |   7.2  45.0  235   3  1   9.6   5.3
 11500   8.1  46.6  230   3  1   9.5   5.2 |   8.7  47.7  235   2  1   9.6   5.3
 11000   9.5  49.1  230   2  1   9.6   5.2 |  10.1  50.2  230   2  1   9.5   5.2
 10500  10.9  51.6  235   2  1  10.3   5.6 |  11.5  52.7  230   2  1  10.9   6.0
 10250  11.7  53.1  235   2  1  10.1   5.5 |  12.4  54.3  230   2  1  10.6   5.8
 10000  12.4  54.3  235   2  1   9.0   4.9 |  13.0  55.4  230   2  1   8.5   4.6
  9750  13.0  55.4  235   1  1   9.2   5.1 |  13.7  56.7  230   2  1   9.0   4.9
  9500  13.7  56.7  240   1  1   9.2   5.1 |  14.4  57.9  225   2  1   9.0   4.9
  9250  14.4  57.9  240   1  1   9.6   5.3 |  15.0  59.0  230   1  1   9.4   5.2
  9000  15.2  59.4  245   1  1  10.0   5.5 |  15.7  60.3  230   1  1   9.5   5.2
  8750  15.9  60.6  245   1  1  10.1   5.5 |  16.4  61.5  230   1  1   9.3   5.1
  8500  16.7  62.1  245   1  1  10.2   5.6 |  17.1  62.8  225   1  1   9.5   5.2
  8250  17.4  63.3  245   1  1  10.6   5.8 |  17.9  64.2  230   1  1  10.2   5.6
  8000  18.2  64.8  250   1  0  10.1   5.5 |  18.6  65.5  235   1  1   9.7   5.3
  7750  18.9  66.0  250   1  0   9.2   5.1 |  19.3  66.7  230   1  1   8.8   4.8
  7500  19.6  67.3  250   1  0   9.9   5.4 |  20.0  68.0  225   1  1   9.4   5.2
  7250  20.4  68.7  255   1  0  10.7   5.9 |  20.7  69.3  230   1  1  10.0   5.5
  7000  21.2  70.2  260   1  0  10.2   5.6 |  21.5  70.7  230   1  1   9.8   5.4
  6750  21.9  71.4  260   1  0   9.2   5.0 |  22.2  72.0  230   1  1   9.2   5.1
  6500  22.6  72.7  260   1  0  10.1   5.5 |  22.8  73.0  225   1  1   9.6   5.3
  6250  23.4  74.1  265   1  0  11.6   6.4 |  23.6  74.5  230   1  1  10.4   5.7
  6000  24.3  75.7  275   1  0   9.8   5.4 |  24.3  75.7  230   1  1   9.6   5.3
  5750  25.0  77.0  275   1  0  13.0   7.1 |  25.1  77.2  230   1  1  10.9   6.0
  5500  26.4  79.5  275   1  0  24.6  13.5 |  26.0  78.8  225   1  1  15.9   8.7
________________________________________________________________________________

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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