bringing clouds and precipitation

A low is represented on a weather map by a red "L". As a cyclone approaches, the likelihood of clouds and precipitation increases.

Winds flow counterclockwise around a low pressure center in the northern hemisphere and temperatures are dependent upon the location relative to the low. Southerly winds associated with an approaching cyclone are likely to result in warmer temperatures while northerly winds found on the backside of a low, or once a low has passed through, typically result in a cooling trend.

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.