MDE Unveils New Air Quality Forecasting System

Forecast zones increase from four to ten, ensuring more accuracy.

The Maryland Department of the Environment (MDE) has unveiled a new air quality forecasting system for the state that more than doubles the number of designated areas where forecasts and current conditions are available.

The ten forecast regions in the state have year-round particle pollution forecasts and ground-level ozone pollution forecasts from April through September. They replaced the previous air quality forecasting system with only four regional areas — Baltimore metro, Washington D.C. metro, Eastern Shore, and Western Maryland.

“These timely improvements deliver more precise and localized forecasting to benefit public health and the environment for all Marylanders,” Environment Secretary Ben Grumbles said.

According to an MDE press release:

The former Baltimore metro region will have a more condensed metro region forecast and two additional regions: Northern Baltimore and Northeast Maryland. The panhandle of the state has been expanded into the Western Maryland and Hagerstown forecast areas. The Eastern Shore has been further refined into upper and lower sections. The former D.C. metro area will now consist of three forecast zones — Suburban DC, Southern Maryland, and Maryland Piedmont.

Here are some more details about the new air quality forecasting zones and the reasons for adding more regions:

Western Maryland/Hagerstown – Garrett and Allegany counties in Western Maryland are higher elevation and more rural and have different air quality from the populated valley around Hagerstown, which has a distinct airshed along Interstate-81.

Maryland Piedmont – This region is a transition from the higher terrain to the west and lower coastal plain to the southeast. It generally does not have heavy influence from urban pollution, making it distinct from other areas.

Northern Baltimore –The higher elevation north of Baltimore is above the coastal plain, making the region less susceptible to poor air quality than at the lower elevations. If air quality is poor, it stems from long-range transport of pollutants from out of state and Baltimore.

Northeast Maryland – Northeastern Maryland is different from the rest of the state because its air quality is related to breezes from the Chesapeake Bay. The region is particularly susceptible to pollution from Baltimore or boats that may be pushed northeastward, impacting only this region.

Metro Baltimore – The Baltimore City area has many pollution sources locally from industry and population density and is impacted by its own pollution when winds are light.

Suburban D.C. – Typical surface flow is from the west or southwest, making this semicircle to the east of D.C. an area susceptible to pollution from the greater D.C. and northern Virginia region.

Upper Eastern Shore/Lower Eastern Shore/Southern Maryland – The upper Eastern Shore of Maryland occasionally finds itself in the plume of the I-95 corridor from Washington D.C. to Baltimore. The Lower Eastern Shore has its own, cleaner airshed. Southern Maryland also is outside the urban pollution plume.

Visit the MDE website for more information.