Isaac Spins in Gulf; Landfall Late Tuesday-Early Wednesday
This Monday night, Isaac is still on the verge of earning full fledged hurricane status (74 mile per hour sustained winds), his somewhat contorted circular wind field showing no signs of growing exponentially.
In fact, despite what some computer projections have been hawking, it appears Isaac will struggle to get much above a minimal 75 mile per hour hurricane come landfall lateTuesday-early Wednesday.
That opens the door for a storm that generates only marginal wind damage and modest storm surge. Admittedly the storm seems to have been overforecasted. To some that makes Isaac's evacuations more of an over-reaction than a necessary precaution. Can't say I disagree.
If this trend holds true, perhaps we should have honed in closer on what Isaac did as he crossed the Florida Keys? Recall after pounding Cuba with torrential rains and gale force winds on Saturday, Isaac spent all day Sunday strafing South Florida with rain and wind. Still overall run-of-the-mill tropical storm conditions are the best he could muster.
Strangely that day long trip over water did not add the expected steroidal energy boost to coronate Isaac as a hurricane. Now after 24 more hours over open Gulf waters, Isaac has struggled to increase in strength. Still not a hurricane at 10 pm!
That’s surprising since Isaac has been churning over very warm Gulf waters including the notoriously tepid Loop Current. The best computers we have to simulate these storms insisted on the steady intensification idea. Being mere humans, many meteorologists including me bought those inton those projections.
But hurricanes need more than warm water to sustain themselves. They need buoyant tropical air to allow thunderstorms to thrive and light, non-sheering winds aloft to create the ultimate environment for the planet’s greatest storm.
Turns out, so far at least, those perfect conditions have not materialized.
So the most likely scenario now focuses on Isaac making a landfall in Southeast Louisiana-Southern Mississippi. This exposes parts of those 2 states and Mobile Bay Alabama to a 24-36 hour relentless pounding of strong onshore southeast winds. That constant wind will pile water into low lying Inlets, bays and causeways. The resulting flooding of low lying areas will tear away at beach dunes and rip apart docks and marinas.
In addition, the east flank of the storm will be notorious for flash flooding rains and brief tornado spin ups. Again all these effects are consistent with a minimal hurricane, strong tropical storm.
Here’s a link to the NHC for all the data you need to track Isaac.
For our area, I feel confident to state that by the weekend the remnants of Isaac will have gained enough latitudinal push (northward movement) to thrust the tropically humid air of Isaac's ancestory (tropics near the Virgin Isles) into the Ohio, Big Sandy and Kanawha Valleys. With a dewpoint rise to 70-75, some of the muggiest air of the summer will arrive late Thursday and last through the weekend.
That means River Days goers in Portsmouth and folks taking in the Tribute to the River Festival in Point Pleasant will find their parades hot and muggy affairs. Saturday night concert goers at the Catlettsburg Courthouse stage will likely find the air hot and steamy.
The Portsmouth parade kicks off late morning and the Point Pleasant “Boat Parade” at 2. Plan on having a cooler of water and bottle of SPF 30 on hand for those events.
In Morgantown, the Friends of Coal Bowl likewise will be a sultry affair with highs near 90 but inside the stadium real feel readings will crest well into the sweaty 90s.
As for Myrtle Beach, go ahead with your Labor Day weekend plans with the notion of plenty of muggy beach sunshine, but a splash and dash thunderstorm appearing every afternoon.
Back Tuesday with some new hopefully credible insight.