Tropical Depression #9 (was Potential TC #9, trying to be Humberto)

The center of circulation for the system keeps trying to reform north and east, which is good for The Bahamas, great for the US, and really bad for the forecast models statistics.  At 48 hours we would expect the track error to be under 100 miles; it’s pushing 300 right now on this storm … the latest National Hurricane Center track keeps the storm well offshore from the excitable denizens of Coastal Georgia and South Carolina.  Hopefully the worst of this will say northeast of the ravaged areas of The Bahamas.  Those in Central Florida should probably still keep an eye on it to make sure it turns as expected, given you are in a Tropical Storm Watch, but anything approaching tropical storm conditions are looking more unlikely.  If the storm intensifies as forecast, Bermuda may be at risk next week.  Here’s the swath of doom …

Dorian update 5pm Wednesday 4 September 2019

Dorian has been tracking to the right of the forecast path all afternoon, and the heavier rain bands have also been staying off of the Georgia shoreline.  Winds at the Georgia stations have all been below tropical storm force.  Here is the satellite and radar views at around 4:30pm … as always, click to embiggen.

From a forecast standpoint … not a lot changed with the 5pm NHC forecast, or in any advice or recommendations.

For Georgia and the Lowcountry of SC, we are still in for a blustery night. There is still the potential for some strong cells to come onshore, and everything is scarier in the dark (especially if the power goes out!).  There is some tornado risk, but that is probably more of an issue as the storm further north.   I think the flood risk is a bit less now for Chatham/Beaufort area, gauges are currently running about a foot below the forecasts from even this morning. That’s still above flood stage, so the “usual suspects” are still at risk of some flooding.  If you are in coastal Georgia or the Lowcountry, you might as well stay put at this point unless you are in a flood prone place or mobile home very close to the coast. Further north towards Charleston and above the flood and wind risk is higher.   The big question now is how the storm moves and turns towards the northeast, and if it manages to avoid a brush with the northern South Carolina and North Carolina/Outer Banks area.

Hurricane Dorian Update, 5pm, Monday 2 September 2019 (nothing really changed)

Meet the new track, same as the old track …

The track is maybe a bit further offshore from Florida – and as noted with this storm, every bit helps.  Damage estimates in Florida dropped by half (from $8 to $4 Billion) with this forecast.  But, as NHC correctly notes, an equally small shift back would bring hurricane force winds over inland areas and the impacts would double or more again.  Hurricane watches have been extended further north, but that’s just because there is the potential for hurricane force winds within 48 hours.  Nothing to freak out about that these watches are changing to warnings – nothing has changed in terms of the forecast or potential impacts.

Given this, nothing has changed from the earlier posts.  The slow drift should end this evening and the storm will start moving again.  Once it does we will be able get a better handle on the impacts to northern Florida, GA, SC, and later potentially NC.

For the Georgia coast, we’re still expecting storm surges of around 3 feet above the normal tide levels.  For comparison, a couple feet higher then the high tides over the weekend – but short of the peaks seen in the last two last years.  That’s around 11 feet at the Fort Pulaski Gauge (or 3 feet above the normal high tide line).  If you are on the coast and saw flooding in Matthew or Irma, hopefully it won’t be that bad, but smart to plan on those levels given the prolonged onshore winds.  Winds are still expected to be tropical storm force right on the water, and lesser (but gustier) inland, so that’s branches breaking, a few trees down, power outages, mostly confined to the coast, so nothing catastrophic.  Again, that’s the most *likely* outcome based on the forecast track.  For planning and safety purposes, use good judgement.

A few thoughts about waiting for storms

First, nothing substantially changed about Dorian since this morning’s review.

I see there are a lot of new people around (Facebook is now over 15 thousand followers, which is scary/surprising, you people need a life!), so a few thoughts about real time storm events and this blog for those new to this.

Originally I had a blog for business purposes,and as part of research outreach.  It actually got started as part of a NOAA grant I was working on with the University of Central Florida in 2004-5 or so, trying to figure out better ways of conveying storm risk to the unwashed masses.  Those maps that you see here labeled with “plain english” categories like “branches breaking” or “severe damage” are one of the results of that project.  After that grant ended I let the blog lapse, but the real time discussions got started because friends and acquaintances were always asking what I thought, and I got tired of repeating myself so I started posting again. In truth, I’m disappointed so many people say this is the most calm and reliable info they have found, so I guess I’m stuck with it.

I don’t make any money off of this; you will see no blipverts here, any you see on FB or Twitter aren’t mine and have nothing to do with Enki.  It annoys me when people think I do, or am doing this for some self-aggrandizing reason.  You note Enki doesn’t even have my name on it.  Because that’s not important.  So, about storms.

My biggest piece of advise is don’t get frantic, and don’t feel you have to chase every little wobble or shift in some model or another to be informed.  As discussed in just about every post, don’t worry about individual track models.  Unless you work at the National Hurricane Center or one of the other major centers, or are doing research in the area of tropical cyclone meteorology, to be blunt, you don’t have the background to interpret them (and chances are neither does the TV meteorologist showing you that fancy animation).  If you notice, when I do discuss an individual track model, it’s virtually always in the context of the official forecast, or as a whole to illustrate a point.  Unless you have some specialized need for more warning (in which case the TV/Media speculation isn’t going to help you), for planning purposes all you really need are the NHC official forecasts.  As those who have followed for a while know I like their Key Messages product, You’re not going to do better.

So how often should you try to get updates?  Unfortunately, the TV/”news”/social media beast wants to be fed, and fed often.  But that’s counterproductive for hurricanes.  Things just don’t change that fast and when they do, if you’ve been following all along, you’ll have plenty of time to react.  Blown forecasts or genuine surprises are really rare – but people tend not to think that because “the beast” has to play up minor differences and “the latest tracks” to keep you engaged.  Unfortunately, that is stressful.  Don’t play that game.

Generally speaking, checking twice a day, in the morning and after school or work in the evening, are all you need in most cases.  Check the NHC forecast, check to see if watches and warnings are up for your area, check your local Emergency Management Agency or local media to see what actions are being recommended (try to set aside all the noise over what if’s).  Then decide what you are going to do, based on the PLAN YOU DEVELOPED BEFORE HURRICANE SEASON (or right now this minute drop everything, if you live in a hurricane prone area and haven’t yet)!   The basic rule for hurricanes is “evacuate from water, shelter from wind” so know if you are in a flood zone (don’t forget rainfall induced flooding of creeks, rivers, and stuff that becomes a creek or river if you get enough rain!)  A lot of communities also evacuate for wind.  I have issues with that for other than very high winds because it vastly increases the disruption (and risk) for the majority of people, but I certainly understand not wanting to be out of power for two or three weeks (months if you live in Puerto Rico, but that’s a different rant).  Of course, the calculations are a bit different for people with health problems.  But for 95% of people and businesses, that’s it.  The five days notice you get, assuming you have a plan, should be enough.  If they aren’t, the problem is the forecasts uncertainty explodes beyond that (which is why NHC only goes to five days) and the “downside” of disruption outweighs any benefits of early action.

I hope that helps.  Note that I generally only post twice a day, early (6-7am), and late afternoon (4-6 pm) unless something really  changes.  Also, it has reached the point where I get so many messages and requests for specific guidance that I just can’t answer them all.  Sorry about that!  Sometimes people ask if they can contribute to keep the site going.   I really appreciate that! Even though it’s not for this, I’ve got good funding at this point (even if it, like most research funding, isn’t always as stable as I’d like it!) so I’m fine.  If you want to help please contribute to a Caribbean relief effort.  I spent a lot of time working with Caribbean governments and agencies in the 90’s and 2000’s, and while I can’t stand the sun in the tropics (I burst in to flames) I love the region.  If not that, find an effort to help the less fortunate here in the US, or an animal rescue group.  I have two feral/rescue cats in the office you may see in pics from time to time … so their colleagues always appreciate a helping hand.