A powerful low-pressure system will drift northward into central Canada and gradually weaken, although a trailing cold front will continue to generate scattered showers and locally severe thunderstorms.  By late Thursday, the front will stretch from the northern Atlantic States to the central Gulf Coast.  Meanwhile in the tropics, forecasters will monitor former eastern Pacific Hurricane Agatha, which made landfall on Monday on the southern coast of Mexico.  Agatha’s remnants may have an opportunity for re-intensification later this week over the western Caribbean Sea or the southeastern Gulf of Mexico. 

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