Milton Tuesday morning update(8 Oct 24)

TL;DR: Milton is on track to be a catastrophic storm for Central Florida (the Tampa-Orlando-Daytona, I-4 Corridor). It will have impacts across much of the state, including the east coast. It may produce tropical storm conditions in the far south coast of Georgia, but most of the Georgia and South Carolina coast should experience sub-tropical storm conditions with some shallow flooding around high tide Thursday. In all cases, follow the advice of local emergency managers, and don’t bet on forecasts being either right or wrong!

Milton is a small but powerful hurricane, undergoing an eye replacement cycle this morning and the eye is no longer distinct …

It is important to realize hurricanes aren’t solid objects or disks. The eyewall is actually a tight band of convection (thunderstorms) cells that are continually building, moving, and decaying. Sometimes, especially with intense hurricanes, a new eyewall forms outside the old one, choking off the old eyewall and replacing it. This causes fluxuations in wind speeds in the eye (but often not in the more distant parts of the storm). That is what is going in in Milton this morning. It’s interesting, gives people something to talk about as the peak winds oscillate up and down, and can be important for damage at landfall depending on when in the cycle it hits our stuff.

The latest from NHC is in their increasingly dire Key Messages regarding Hurricane Milton (en Español: Mensajes Claves). Here is the predicted damage swath using my TAOS(tm) TC model – note the key, describing the likely conditions in plain language:

The NHC forecast track has remained remarkably consistent over the last couple of days. Take a look at this, comparing this morning’s forecast with the 11am forecast from yesterday:

The intensity forecasts also haven’t changed a lot either. For all the breathless excitement about Milton becoming a Category Five (which is in fact interesting and important), it has not changed the forecast or predictive impacts for Florida or the Southeast Coast – the storm isn’t expected to be a Cat 5 by then, it will most likely be a strong Cat 3 transitioning into an extratropical system at landfall. So what does it all mean?

I could copypasta most of what was written two days ago (and maybe I did with some minor edits 😛 ). Landfall looks to be in the early hours of Thursday morning, but tropical storm conditions will arrive over much of the West coast of Florida during the day Wednesday. If you’re in the warned areas, especially areas urged to evacuate, you should follow that advice – today.  Unfortunately given the size of the storm it looks to hit the northern Gulf coast areas in the Big Bend with gusty wind, waves, and rain, perhaps close to tropical storm conditions. I expect wobbles and minor track shifts over the next 24 hours, so don’t panic and don’t chase the windshield wipers – concentrate on the watch and warning areas, and the forecast damage swath, which is huge covers the central and northern parts of the Peninsula, and severe impacts will be felt far to the southwest, even to Marco Island.

The East coast of Florida, especially from the Cape to Jacksonville, should also prepare for hurricane conditions – probably Cat 1 or low 2, but again follow the advice of your local EMAs.

For coastal Georgia, from south to north, the Brunswick area might see close to tropical storm conditions depending on the exact trajectory offshore, and how distorted the wind field gets from the transition to extratropical storm characteristics. It looks like it will be breezy in Southern Coastal Georgia later today and tonight, with winds picking up all day tomorrow. This will cause some shallow coastal flooding at each high tide, peaking Thursday afternoon, probably in the 3ft above normal high tide range.

Moving north the threat and the wind impacts will decrease, although again with the sustained onshore winds there will be shallow coastal flooding along the marshes and beachfronts. Savannah and inland coastal infrastructure is still fragile from Helene, so even winds 25 mph gusting to 35 mph (both GFS and ECM show about that at the surface, higher out on the water and Islands somewhat) may cause some power outages; inland winds should be less. So on this track and forecast, Thursday morning from before dawn to late afternoon will probably be gusty with some rain bands, but at least it will be daylight for most of the storm. Frogmore proper should see sustained winds around 25mph with gusts to 35. Hilton Head Island (South Frogmore Beach) will be a bit higher and gustier, 30mph gusting 45. Inland (Savannah) 25 gusting 38.

That level of wind typically only causes scattered outages, but I am a bit concerned about the fragility of the infrastructure after Helene and, of course, there are still people without power across the region. Also, many damaged trees have not been properly stabilized and cleaned up, so there is a lot of debris stacked up that can be tossed around and cause mischief, so be careful.

As for flooding, it looks to be confined to the coast as rain rates should be manageable. The tide forecasts look to peak on Thursday afternoon:

At that level there is typically flooding in some areas like Shipyard Road, Burnside Island, Catalina Drive and Lewis Ave on Tybee. US 80 might get a little water if the tides run higher than expected. So if you are on the marshes and flood with abnormally high tides, be ready for that.

That’s what it looks like at the moment (Tuesday morning). Will post again tomorrow (Wednesday morning) when the storm is about a day from landfall. Meanwhile, again if you are in the damage swath you need to take immediate action, especially if in evacuation zones where high storm surge is likely. The coastal stretch from Bradenton to Naples is especially vulnerable to high storm surges, and this storm could easily hit 18 to 20 feet in places with high waves. That’s not survivable. Storm surge flooding on Florida’s east coast isn’t likely to be nearly that high but know your risks and evacuate if requested.