Outflow Phenomena

This section is on visual identification of macrobursts, microbursts, gust fronts and other outflow phenomena. Damaging thunderstorm winds have been termed downbursts by renowned severe storm researcher Dr. Ted Fujita. Dr. Fujita further classifies these events as macrobursts (greater than 2.5 miles in diameter) and microbursts (less than 2.5 miles in diameter).

The problems that aircraft have had with thunderstorm-induced wind shear, particularly microbursts, indicate that the spotting and reporting of microbursts is of paramount importance. Although some spotters will think that events such as microbursts and flash floods are less dramatic than tornadoes, in reality, they are just as lethal, if not more so, in some circumstances. Hopefully, pilots will find these slides beneficial in identifying outflow structures that could result in dangerous approach or take-off conditions, and delay their subsequent actions until danger has passed.

Terms for using data resources. CD-ROM available.
Credits and Acknowledgments for WW2010.
Department of Atmospheric Sciences (DAS) at
the University of Illinois at Urbana-Champaign.