Milton update Monday 7 October 2024

Milton hasn’t moved a lot over the last day, but is slowly strengthening and is moving east. It is expected to start to move rapidly towards Florida later today, spiking up to be a major hurricane tomorrow before starting to weaken and transition into an extratropical storm as it crosses Florida. Warnings are up for Yucatan, and watches (with evacuations starting) for Florida. The official NHC word is best found in their Key Messages regarding Hurricane Milton (en Español: Mensajes Claves). Here’s this morning’s overview map:

As noted before, where Milton is going isn’t in too much doubt: somewhere in Central Florida, probably over or south of Tampa, although the details matter a lot in terms of damage, they don’t matter that much as to “what to do.” That’s simple. If advised to evacuate, get out. Most of Florida will see winds and a large swath will get varying degrees of damage as seen in this map generated by my TAOS(tm) TC system – note the table describes average impacts in each band (details on the map meaning are at this link).

With all the focus on the potentially catastrophic impacts on Tampa, we need to keep in mind that while a southward trek will mean a smaller damage number, a lot of people live in that part of Florida. Communities like Sarasota, Venice, Port Charlotte and if the storm is large or farther south, Sanibel/Cape Coral/Fort Meyers. These have been hit hard by storms in the past and received inadequate warning (from the media especially) because of the focus on Tampa/St. Pete and the I-4 corridor. Here is the same map zoomed in a bit. Note even on this track the main impacts are displaced to the south of the Tampa area.

On the east coast, the main risk zone is shifted some what, and for surge and flooding on the coast opposite the west coast and on the north side of the track (remember the winds spin counter-clockwise). So, if this track holds up, Daytona to St. Augustine will see more coastal impacts, whereas the wind swath should be broader and extend from Jacksonville south to Port St. Lucie.

Here are where the highest storm surges are expected, likely 15 to 20 feet at the shoreline, with extensive inland flooding due to all the pre-storm rain:

Here are the model forecasts this morning. I’ve seen more than a few people worrying/scaremongering/clickbaiting about the GFS model (the dark blue line zagging up towards Jacksonville in the map below). Note the official forecast (red line) is about in the middle.

Each one of these lines has a complex story to tell, and all are not equal. It really annoys me when people cherry pick the model that causes them or their target audience the most harm. You can see through this kind of nonsense when for one storm they hype GFS, then the next ECM or CMC (or even switch the highlighted model from one forecast cycle to the next, changing models every six hours!). That’s simply irresponsible, and not how you do forecasting. To begin with, amateurs (and most “professional” meteorologists for that matter) shouldn’t be doing hurricane forecasting. It’s a very specialized area requiring a lot of expertise and a team approach. For the most part, only significant value we can add to the NHC forecasts (especially for the general public) is explaining what their forecast means in terms of impacts (what Enki specializes in), and some factors around it like uncertainty. That’s why I don’t normally show model tracks or spaghetti maps because they can be misleading without a lot of interpretation.

So all that said, what about farther north, for Georgia? Time to copypasta:   In Florida, unfortunately given the size of the storm it looks to hit the northern Gulf coast areas in the Big Bend with gusty wind and rain, perhaps close to tropical storm conditions. I expect wobbles and 100 mile 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. Those in Central Florida should take this very seriously and if on the West coast, get started with the evacuations. It’s also possible to likely the East coast of Florida will have evacuations as well – certainly there will be warnings. And the rest of the swath inland should be prepared to get ready for a rough ride.

Note again there are no signs in the forecast at the moment that this storm will have major impacts in coastal Georgia or South Carolina, much less inland Georgia and North Carolina still recovering from Helene. 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. Moving north the threat and the wind impacts will decrease. Local Frogmore South (Savannah) infrastructure is still fragile from Helene, so even winds 20 mph gusting to 35 mph may cause some scattered power outages, but this is an “inconvenient” situation and not hazardous with a little common sense. The danger zone is south of the GA/FL border. Landfall is forecast to be a bit later, with impacts in Coastal Georgia starting overnight Wednesday and peaking around 9 am Thursday morning in the Savannah area.