The National Hurricane Center says a low pressure system is expected to develop in the Gulf of Mexico today.
"The low should begin to move northward by this afternoon, and a tropical or subtropical depression is likely to form by late tonight or on Friday when the low moves across the western Gulf of Mexico," according to the Tropical Weather Outlook.
The Hurricane Center says crews will fly into the system this afternoon.
"An Air Force Reserve Unit reconnaissance aircraft is scheduled to investigate the disturbance."
Forecasters say that data should help better determine where the heaviest rain will fall Friday night and Saturday.
"Regardless of development, heavy rains should... begin to affect portions of the northern Gulf Coast on Friday."
The Hurricane Center says formation chance is 90 percent.
