RICHMOND, Va. (WTVR) – As Tropical Storm Isaac moves over the very warm waters of the Gulf of Mexico Monday, it is having no difficulty maintaining its strength. In fact, a burst of intensification is expected sometime later today, likely pushing Isaac into the hurricane force wind range of a Category One storm with at least maximum sustained winds of 74 mph. By the time then-Hurricane Isaac makes landfall somewhere along the Louisiana or Mississippi Gulf Coast, it could have maximum sustained winds of 90 mph, along with significant storm surge and flooding rainfall, not to mention the threat for tornadoes.
Even though the red line takes the center of Isaac very near or directly over New Orleans, it is more important to focus on anywhere within the white outlined cone path because at least tropical storm force conditions will be experienced in that zone.
In the late morning update from the National Hurricane Center, tropical forecasters warn of significant storm surge that could reach the following depths (above ground) if the peak storm surge coincides with the normal high tide along the coast:
Southeast Louisiana, Mississippi, and Alabama: 6 to 12 feet
South-central Louisiana: 3 to 6 feet
Florida Panhandle: 3 to 6 feet
Florida west coast, including Apalachee Bay: 1 to 3 feet
The NHC warns, “The deepest water will occur along the immediate coast in areas of onshore flow. Surge-related flooding depends on the relative timing of the surge and the tidal cycle, and can vary greatly over short distances.”
As for expected rainfall, Isaac will feast upon the very warm Gulf waters over which it is passing, only to later belch the moisture back upon land with isolated maximum rainfall totals up to 18 inches possible in southeastern Louisiana, southern Mississippi, southern Alabama, and the western Florida panhandle.
As Isaac chugs inland along the Mississippi Valley region, the forecast scenarios computed by tropical models vary widely, but do indicate much-needed rainfall for parts of the U.S. battling one of the worst droughts in our history.