DEVELOPING: Storm system in Gulf of Mexico forecast to become a tropical storm Thursday, and a hurricane on Friday, NWS says.
System expected to bring storm surge, 6-12 inches of rain in areas.
Tropical storm watch issued for parts of Louisiana coast.
DEVELOPING: Mississippi River at New Orleans now forecast to crest 20 feet above sea level this weekend, the highest crest since 1927, NWS says.
The levees protecting New Orleans are 20 feet.
JUST IN: Louisiana Gov. Edwards issues state of emergency ahead of potential hurricane that could make landfall in the state this weekend. The storm is forecast to bring heavy rains and storm surge. http://nbcnews.to/32fwOue
JUST IN: Hurricane Watch issued for much of Louisiana coast as storm develops in Gulf of Mexico, NWS says.
Storm is forecast to strengthen to hurricane Friday.
Mississippi River at New Orleans forecast to crest at highest level since 1927 this weekend.
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