Low pressure system over the eastern United States

This visible image of the Great Lakes low pressure area was taken from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Aqua satellite. It was taken at 19:05 UTC (3:05 p.m. EDT) on Monday, Sept. 26, 2011.

Credit: NASA Goddard MODIS Rapid Response Team

Two Instruments on NASA's Aqua Satellite Catch the Pesky Great Lakes Low

A low pressure area has been sitting over the Great Lakes region for about a week now, keeping the region and the U.S. northeast and Mid-Atlantic under cloud cover. NASA's Aqua satellite flew over head yesterday, Sept. 26, and captured two views of it from space.

That low pressure area continues to spin counter-clockwise today over the Great Lakes. Its centered over northern Illinois and southeastern Wisconsin and is once again going to keep the region cloudy, cool and wet with showers.

When the Aqua satellite passed overhead Monday afternoon at 3:05 p.m. EDT (Sept. 26) a detailed, clear image was captured from the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument . The clouds from the low spread over Illinois, Wisconsin, parts of Iowa, northeastern Missouri, southeastern Minnesota, Michigan, Ohio, Indiana, Pennsylvania, Kentucky, Tennessee, Alabama, Mississippi, Georgia, and the northeastern and Mid-Atlantic states.

A second visible image was captured by the Atmospheric Infrared Sounder (AIRS) instrument that also flies aboard NASA's Aqua satellite and showed the huge comma shape of the storm that spans the U.S. from its northern to southern borders. (seen here: www.flickr.com/photos/gsfc/6188946564 )

According to the National Weather Service, the low will finally start moving to the east as an upper-atmospheric trough (an elongated area of low pressure) continues to strengthen and move into the upper Midwest. However, a ridge (elongated area) of high pressure will slow its move eastward, so it will be slow clearing this week in the northeastern and Mid-Atlantic U.S.

Rob Gutro
NASA's Goddard Space Flight Center

NASA image use policy.

NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission.

Follow us on Twitter