Tropical Storm Issac building strength; focusing on New Orleans

Tropical Storm Issac is still a tropical storm at the moment but is growing in strength and will likely be a hurricane during the night. Weather Underground is reporting sustained winds of 70 mph with some gusts reaching as high as 80 mph. Forward motion is currently at 10 mph and has been slowing. This will allow Issac to pull together and strengthen. Currently tropical storm force winds extend over 200 miles from the center of the storm. Issac is projected to grow to a category 2 hurricane with winds up to 100 mph.

Category 2 Hurricane Isaac projected to hit Louisiana coast south of New Orleans Tuesday afternoon: 4 p.m. update (Times-Picayune)

Tropical Storm Isaac is gaining strength over the warm waters of the Gulf of Mexico and is expected to reach Category 2 strength, with winds of 100 mph, as it hits the Louisiana coast at or just west of the mouth of the Mississippi River Tuesday afternoon. The forecast's slight nudge west of Isaac's track continues to put the more dangerous eastern side of the storm over the New Orleans area.

The entire New Orleans area remains under a hurricane warning. Forecasters with the Slidell office of the National Weather Service are predicting that tropical storm-force winds will be approaching central New Orleans by 4 a.m. Tuesday, with gusts approaching 82 mph as the center of the storm crosses Lake Pontchartrain on Wednesday at 7 a.m. Because of the long period of high winds, more than 24 hours, they warn of major electrical outages.

--snip--

"As Isaac comes ashore, it's going to be slowing down and somebody's going to get an awful lot of rain," said Hurricane Specialist Eric Blake, a native of Metairie, a 12-year veteran of the hurricane center. "The rain is right now approaching the mouth of the river and should strengthen overnight."

Isaac's unusually large size -- outer bands are dumping flooding rains on the east coast of Florida on Monday afternoon -- are believed to be one reason it has been slow to gain intensity, Blake said.
But that's changing, as seen by an increase in wind speed to 70 mph at 4 p.m., and another drop in its forward motion, to 12 mph, as it moves northwest toward the Louisiana coast from its present central Gulf of Mexico position 255 miles southeast of the Mississippi's mouth.

The storm appears to have a slight westward wobble in its track but all of the computer models are converging onto southeast Louisiana. This puts the dirty side of the storm over Mississippi and parts or all of New Orleans. It appears that the big threat from tis storm will be flooding from very heavy rain. Also the storm surge accompanying at Cat 2 storm as it makes landfall could be 6 - 12 feet along the Mississippi and Louisiana coasts.

Currently no mandatory evacuation is being ordered ahead of this storm, but anyone in the path of Issac should monitor its progress carefully and be prepared to evacuate or hunker down as recommended by the authorities.

Isaac Not Another Katrina, But Still Dangerous (AccuWeather)

While from a core meteorological standpoint Isaac will not be another Katrina in terms of intensity, it is still a dangerous storm.

Isaac is forecast by AccuWeather.com to make landfall as a hurricane in Louisiana and will bring the risk of storm surge flooding, inland flooding, damaging wind, tornadoes and beach erosion to part of the central Gulf Coast area.

According to AccuWeather.com Hurricane Expert Dan Kottlowski, "The angle at which Isaac could come ashore could still drive a substantial amount of water inland quickly over southeastern Louisiana and southern Mississippi."

As a result a relatively weaker storm (Category 1 or 2), when compared to Katrina (Category 3 at landfall in La./Miss.), could still pack a considerable punch.