NEW ORLEANS – A slow-moving tropical system packing walloping rains is slogging its way to the Gulf coast, which could be drenched with up to 20 inches, leading Louisiana’s governor to declare a state of emergency Thursday because of the threat of flash flooding. Tropical storm warnings are out from Mississippi to Texas. The National Hurricane Center said the system that is now a depression in the Gulf of Mexico will dump 10 to 20 inches of rain over southern areas of Louisiana, Mississippi and Alabama through Sunday. By today, it could become Tropical Storm Lee. As hurricane season is hitting its peak in the Atlantic, storm watchers were monitoring three disturbances. Besides the Gulf depression, Tropical Storm Katia is spinning in open waters. It weakened from a hurricane earlier in the day though forecasters say it will again grow stronger. It was about 930 miles east of the Leeward Islands and moving west near 18 mph with maximum sustained winds Thursday evening near 70 mph. It could become a major hurricane this weekend, but forecasters said it’s too early to tell if it will hit the U.S. In yet another system, a slow-moving low pressure system about 360 miles north of Bermuda stood a 50 percent chance in the next two days of becoming a tropical cyclone.