Gustav will continue to be a threat to the lower Mississippi Valley and the Arklatex despite weakening into a tropical depression. Meanwhile, Hanna has weakened today and Tropical Storm Ike spins farther out in the Atlantic.

The AccuWeather.com Hurricane Center reports that Gustav will spread flooding rain into the Arklatex today. AccuWeather.com meteorologists are also closely watching Tropical Storm Hanna, which will impact the U.S. later this week, as well as Tropical Storm Ike and Tropical Depression 10.

Gustav weakened overnight to a tropical storm, with sustained winds decreasing to near 35 mph. At 4:00 a.m. CDT, Gustav was 135 miles northwest of Lafayette, La.

Despite losing strength, the storm will continue to cause widespread flooding and damage along the Gulf Coast. Among the long list of concerns is the potential for damage to the sugarcane crop in south-central Louisiana.

The main threats with Gustav will be the flooding rain and tornadoes on the northern and eastern flanks of the system. The storm will continue to move toward the northwest into northeastern Texas today, before turning northward by midweek.

According to the Severe Weather Center, an additional 2 to 4 inches of rain will fall over southern portions of Louisiana and Mississippi, with 4 to 8 inches forecast from northern Louisiana to southern Arkansas through Wednesday evening. Locally higher amounts, upwards of 20 inches will be possible through Thursday.

Rainfall amounts from Gustav over the 36-hour period ending today at 1 a.m. CDT include:

• Grand Isle, La.: 14.76 inches
• Alexandria, La.: 4.97 inches
• Lafayette, La.: 4.23 inches
• Biloxi, Miss.: 3.72 inches
• Mobile, Ala.: 3.10 inches

More flooding and severe weather is forecast today in the lower Mississippi Valley, including southern Louisiana and southern Mississippi. The tornado threat today will stretch from the western Florida panhandle to southern Arkansas and southeastern Oklahoma.

The Severe Weather Center lists the numerous storm-related watches and warnings in effect from the Florida panhandle to eastern Texas.

Gustav will be pulled to the north by a front slowly crossing the Plains. Two to 3 inches of rain is forecast later in the week in northeastern Arkansas and southwestern Missouri. By Friday, the rain from Gustav will reach Illinois and the upper Great Lakes.

Hurricane Gustav made landfall on Monday morning southwest of Port Fourchon, La., as a Category 3 hurricane with maximum sustained winds above 110 mph.

Pounding waves from Hurricane Gustav cause a beach road to collapse in Bay St. Louis, Miss., Monday, Sept. 1, 2008. (AP Photo/ Rogelio V. Solis)

A storm surge as high as 14 feet battered the Gulf Coast from Florida to southwestern Louisiana.

In New Orleans, the storm surge sent water over the walls of the Industrial Canal along the Upper Ninth Ward; however, the levees were not breached.

Strong winds tore roofs off houses and toppled power lines. According to the Associated Press, more than 1,000,000 homes were without power at the height of Gustav's impact.

Peak wind gusts recorded in Louisiana through 1 a.m. CDT Tuesday include:

• Grand Isle: 105 mph
• Baton Rouge: 95 mph
• Lafayette: 77 mph
• New Orleans: 72 mph

New Orleans Mayor Ray Nagin said residents could return later this week. Federal, state and local officials will assess hurricane damage today. Some businesses could reopen as soon as Wednesday.

AccuWeather.com Hurricane Center forecasters are focusing on Hanna, which has weakened to a Tropical Storm after being upgraded to a hurricane on Monday.

Meteorologist Rob Miller says Hanna has been weakened by wind shear as it drifts erratically over the southwestern Bahamas, about 385 miles southeast of Nassau.

Through Thursday, the storm will bring heavy rain to Hispaniola, the Turks and Caicos, and the central and southern Bahamas. A hurricane warning remains in effect for the central and southeastern Bahamas and the Turks and Caicos islands.

The effects of Hurricane Hanna could reach the Florida coast by Thursday, with landfall forecast along the southeast coast by Friday. All interests along the Eastern Seaboard should closely monitor Hanna and prepare an emergency plan.

Hanna has already stirred up dangerous surf and rip currents along the Southeast coast from the Carolinas to Florida. By Friday, the threat will extend north as far as the beaches of Long Island and southern New England.

On Monday, one man drowned in a rip current two miles south of Kure Beach, N.C., and 27 people were rescued at Wrightsville Beach, N.C.

Meanwhile, Tropical Storm Ike is in the central Atlantic, less than 1,400 miles east of the Leeward Islands. Maximum sustained winds are near 50 mph. Ike could become a hurricane over the next 24 to 48 hours as it moves west through the Atlantic.

Now there is a fourth area to watch in the Atlantic. Tropical Depression 10 organized this morning southeast of the Cape Verde Islands. This storm will have a long way to travel before presenting a concern to the U.S.