Inland flooding from Isaac will expand over the balance of the week aiming toward southwestern Arkansas as heavy rain begins to crawl away from the Gulf Coast.
Slow-moving tropical systems have long been known to cause some of the worst floods imaginable. That remains a primary concern with Isaac as it drifts slowly inland.
Hurricane Isaac moved over southern Louisiana Tuesday night and will soon begin a curved path into the southern Plains and Midwest over the balance of the week.
Portions of southern Mississippi and southeastern Louisiana are bearing the heaviest amount of rain and coastal flooding during Wednesday.
A general 12 to 18 inches of rain will fall in southern Mississippi and southeastern and central Louisiana with the potential for local amounts surpassing 20 inches.
Rainfall occurred over a broad area of the South during the first part of this week and pockets of heavy rain will continue to emerge.
The I-95 corridor, along the Atlantic Coast in the South was hit Monday with drenching rain and gusty thunderstorms.
Places as far away as Charleston, S.C. were inundated with torrential rain, due in part of Isaac Tuesday.
Communities from New Orleans, Houma and Baton Rouge to Gulfport, Biloxi and Mobile will continue to experience windswept, torrential rain and urban flooding as Isaac roars along the shore Wednesday.
As Isaac waddles inland Wednesday and Thursday, drenching showers and locally gusty thunderstorms will continue to affect Atlanta, Charleston, S.C. and Huntsville, Ala.
Downpours are forecast reach into drought areas of Little Rock, Ark.; Shreveport, La. and Memphis, Tenn. as the week progresses.
Keep checking back with the AccuWeather.com for the latest on Isaac as to where the flooding versus beneficial rain will occur.
Weakening steering currents over the United States have caused Isaac's forward speed to slow.
According to AccuWeather.com Hurricane Expert Dan Kottlowski, "A slow-moving tropical storm or hurricane has the potential to drop tremendous rainfall and produce major flooding."
Meanwhile, folks over the Mississippi, Ohio, Missouri and Arkansas basins would welcome any non-flooding rainfall. A large part of this area remains in a drought as a result of the blistering summer of 2012 and abnormally warm and dry conditions during the winter of 2011-12.
Expert Senior Meteorologist Alex Sosnowski contributed to the content of this story.
Temperatures will be a few degrees below average across the UK this weekend, but largely dry conditions are expected.
After no rain for almost a month, Santiago braces for rain early in the week. Cool air follows, spreading into Chile, Argentina and Uruguay mid-week.
There is a significant chance that Jimena will turn back toward Hawaii and threaten the islands during the second week of September.
An unusually strong push of cool air for early September will move southward along the Atlantic Seaboard into the Labor Day weekend before July-like heat returns by next week.
Steering winds could take Ignacio, as a remnant storm, into the southeastern arm of Alaska or British Columbia during the middle days of next week.
Strong thunderstorms will roll across the Upper Midwest while rain and strong winds roar through the Northwest this weekend.
Greatest natural disaster for Arizona. Rains in central Arizona caused rivers to rise 5-10 feet per hour, sweeping cars and buildings 30-40 feet downstream. Twenty-three lives were claimed by the floodwaters. This rain came from Tropical Storm Norma.
Los Angeles, CA (1988)
110 degrees -- all-time September record.
Washington, DC (1939)
"Once in a hundred-year rainstorm" 4.40 inches in 2 hours at the Washington Zoo.