What Does National Weather Service Mean By ‘Areal’ Flooding?
As important as weather is to all of us it can also be confusing. Certainly it's hard to predict what the weather will do from day to day; it's especially hard in an area like ours where there are many factors that come into play that affect the weather.
As difficult as weather forecasting can be, it's comforting to know that we can place our trust in the National Weather Service - which has an office right here in Duluth. The Weather Service (NWS) has a full-time staff that gathers data and then uses it to provide accurate forecasts about what we can expect from Mother Nature over a period of time. They also research trends and offer historical data.
Part of the process involves not only proprietary equipment, but also vernacular. By now, most of us have learned to understand the industry-specific language used by the NWS.
One term, though that has caught some off guard this spring is "areal" - used in relation to flooding. Some have postulated that the weather service has made an error (i.e. typo) or that they are using a grammatically-incorrect usage (i.e. "there's a real flood..."). Neither of these hypotheses is correct.
Areal is a relatively-new term used by the National Weather Service - meaning the opposite of a flash-flood. When there is a chance for areal flooding, the NWS is warning the general public that the water will slowly develop over large geographical areas. Their website says that "the flooding normally occurs more than six hours after the rainfall begins, and may cover a large area".
Whatever the source of flooding and whatever type it may inhabit, the threat from water damage is nothing to take lightly. Water can be very destructive. Your best safety defense is to exercise caution and to always listen to the instructions that are given by the authorities.