This story was last updated on Sunday, August 26 at 5:05 p.m. EDT.
A new live blog is online with the latest updates on Isaac.
Isaac continues to spread tropical storm-force winds and bands of heavy rain across South Florida as it passes extremely close to the Florida Keys.
The AccuWeather.com Hurricane Center gives the latest statistics on Isaac, which remains a strong tropical storm.
5:05 p.m. EDT: The Hurricane Watch that has been in effect for the northern Gulf Coast from Morgan City, La., to Destin, Fla., has been changed to a Hurricane Warning. This warning encompasses New Orleans.
5:00 p.m. EDT: The center of Tropical Storm Isaac was located about 40 miles southwest of Key West, Fla. The storm's maximum sustained winds remained estimated at 60 mph.
4:10 p.m. EDT: The AccuWeather.com Hurricane Center issues its latest forecast track map for Isaac.
4:00 p.m. EDT: Word of a delayed report that at 2:07 p.m. EDT Isaac's strong winds downed a tree against a home in the Port Pine Heights Neighborhood on Big Pine Key.
3:46 p.m. EDT: Based on Isaac's current position on radar, the tropical storm will narrowly miss crossing the westernmost Florida Keys this afternoon.
2:51 p.m. EDT: Despite the fact that Isaac weakened earlier this afternoon, AccuWeather.com meteorologists still expect the tropical storm to strengthen into a hurricane over the eastern Gulf of Mexico tonight. Isaac should be a Category 2 hurricane before slamming the northern Gulf Coast around Tuesday night. There is concern that if Isaac remains over water long enough, it will grow to a Category 3 hurricane.
2:25 p.m. EDT: Isaac kicks up highest wind gust in Florida--70 mph at Smith Shoal Light.
2:10 p.m. EDT: Winds gusted to 66 mph at Virginia Key as Isaac approached the Florida Keys.
2:08 p.m. EDT: Homestead Air Force Base holds the title for the highest 24-hour rainfall total across Florida from Isaac with 4.46 inches.
2:01 p.m. EDT: Miami, Fla., recorded its highest wind gust of the day--52 mph.
1:49 p.m. EDT: The center of Tropical Storm Isaac was located about 50 miles south-southeast of Key West, Fla. Maximum sustained winds have decreased to 60 mph.
1:39 p.m. EDT: Received a delayed report of a 64-mph wind gust at Port Everglades, Fla. Reading occurred at 12:10 p.m. EDT.
1:14 p.m. EDT: Latest wind gust from Key West, Fla.: 63 mph.
12:34 p.m. EDT: Winds gusted to 46 mph at Key West, Fla.
11:48 a.m. EDT: AccuWeather.com meteorologists are putting places from New Orleans, La., to Mobile, Ala., to Pensacola, Fla., on high alert as likely communities that will endure a direct hit by Isaac around Tuesday night. Odds favor Isaac track onto the Mississippi coast than the central Florida Panhandle.
11:27 a.m. EDT: Sustained wind speed of 47 mph recorded at Sand Key Buoy near Key West, Fla., with a gust to 51 mph.
11:01 a.m. EDT: Highest wind gust from Isaac so far reported across Florida is 60 mph at Pompano Beach, Fla.
10:58 a.m. EDT: Isaac is currently located about 80 miles southeast of Key West, Fla., with maximum sustained winds of 65 mph. Tropical storm-force winds extend 205 miles away from Isaac's center.
10:55 a.m. EDT: Center of Tropical Storm Isaac can now be seen on the local radar from Key West, Fla. Look north of Cuba and southeast of Key West.
10:37 a.m. EDT: In this video report, Expert Senior Meteorologist Bernie Rayno discusses the potential impacts of Isaac on the oil rigs in the Gulf of Mexico.
10:28 a.m. EDT: Sustained tropical storm-force winds of 41 mph registered at Port Everglades, Fla., with a gust to 55 mph.
10:25 a.m. EDT: Miami's Kendall-Tamiami Executive Airport has picked up 1.48 inches of rain in the last 12 hours.
10:10 a.m. EDT: Updated track map from the AccuWeather.com Hurricane Center. Isaac still expected to cross the Florida Keys later today as a strengthening tropical storm, then will target places around Mobile Bay, Ala., Tuesday night.
10:00 a.m. EDT: The center of Tropical Storm Isaac is located about 110 miles east-southeast of Key West, Fla., or about 122 miles south of Miami, Fla.
9:43 a.m. EDT: A wind gust of 53 mph was reported at Fort Lauderdale, Fla.
9:40 a.m. EDT: AccuWeather.com meteorologists just finished discussing the progress of Isaac and have decided to shift our forecast track map a bit to the west. Tuesday night's landfall is now projected to be around Mobile Bay, Ala., but all residents from New Orleans, La., to Panama City, Fla., should be preparing for Isaac's eventual arrival.
9:37 a.m. EDT: The peak wind gust in the past 12 hours across Florida was 54 mph, recorded shortly before 8 a.m. EDT at Pompano Beach.
9:11 a.m. EDT: Wind gusts to 40 mph whipped through Homestead Air Force Base, Fla., as a band of rain spiraled through.
9:10 a.m. EDT: In this video report, AccuWeather.com Expert Senior Meteorologist Bernie Rayno details Isaac's impacts to Florida.
8:30 a.m. EDT: Tornado watch issued for all of South Florida and the Florida Keys until 5:00 p.m. EDT this afternoon. The twisting motion in the atmosphere created when tropical systems interact with land typically lead to isolated tornadoes.
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