Hurricane Dorian [Merged]

[jonblatho]

Latest GEFS run (still coming in) returns to having most ensemble members showing Dorian either hugging the coastline or making landfall in Florida.

Won’t get another Euro run until late tonight, but this would support a decision to move the track at least somewhat westward with the 11 PM EDT advisory. NHC could also absolutely decide to ignore this current trend and wait for more information, and maintain the current track forecast. Don’t think there’s any reason right now to continue moving the track eastward as they have been.

 

[Rogifan]

Latest GEFS run (still coming in) returns to having most ensemble members showing Dorian either hugging the coastline or making landfall in Florida.

View attachment 855566

Won’t get another Euro run until late tonight, but this would support a decision to move the track at least somewhat westward with the 11 PM EDT advisory. NHC could also absolutely decide to ignore this current trend and wait for more information, and maintain the current track forecast. Don’t think there’s any reason right now to continue moving the track eastward as they have been.

For all those that claim the media/Weather Channel hype these things, all day today The Weather Channel has been pushing this eastward narrative. I watched at the top of the hour and they were treating it as missing all land and barely nudging South Carolina. I hope they turn out to be right but at the same time I hope it isn’t causing people in Florida to let their guard down thinking they’re no longer in danger. A lot of people trust The Weather Channel.

 

[MacNut]

For all those that claim the media/Weather Channel hype these things, all day today The Weather Channel has been pushing this eastward narrative. I watched at the top of the hour and they were treating it as missing all land and barely nudging South Carolina. I hope they turn out to be right but at the same time I hope it isn’t causing people in Florida to let their guard down thinking they’re no longer in danger. A lot of people trust The Weather Channel.

The current NHC track has it missing. This is the same data the weather channel is using. There is only one hurricane track.

 

[Rogifan]

The current NHC track has it missing. This is the same data the weather channel is using. There is only one hurricane track.
View attachment 855567

Sure but some models are shifting. One model showing this:

Of course I understand TWC using the current NHC track but considering how difficult this storm has been to predict it just seems a little to early to call it. I’m still unclear on what exactly caused the models to shift so far east and how they can be certain this far out. Is it normal for a storm this intense to take a sharp turn like that?

 

[MacNut]

Sure but some models are shifting. One model showing this:

Of course I understand TWC using the current NHC track but considering how difficult this storm has been to predict it just seems a little to early to call it. I’m still unclear on what exactly caused the models to shift so far east and how they can be certain this far out. Is it normal for a storm this intense to take a sharp turn like that?

As these storms get closer the data going in gets better so the models will adjust. This is why they have a cone of uncertainty. Anyone in the cone can be affected. I would wait until the Euro comes in as that is the more accurate model. If they both agree then the NHC will likely adjust the track to the west.

 

[jonblatho]

Sure but some models are shifting. One model showing this:

Of course I understand TWC using the current NHC track but considering how difficult this storm has been to predict it just seems a little to early to call it. I’m still unclear on what exactly caused the models to shift so far east and how they can be certain this far out. Is it normal for a storm this intense to take a sharp turn like that?

Yes, it’s fairly common for hurricanes to take pretty wild turns, actually. Hurricanes are fairly shallow in the atmosphere, and it’s really easy for other features to “steer” them, and sometimes the interactions are really hard to predict. In this case, the interactions are dominated by a high-pressure system to Dorian’s north, the strength/size of which was seemingly underestimated by model analyses. That’s why some models are now backtracking to the west a bit as they begin to account for observations indicating that the ridge is a little bit stronger/larger than first thought.

Florida certainly shouldn’t let their guard down yet.
[doublepost=1567299132][/doublepost]

As these storms get closer the data going in gets better so the models will adjust. This is why they have a cone of uncertainty. Anyone in the cone can be affected. I would wait until the Euro comes in as that is the more accurate model. If they both agree then the NHC will likely adjust the track to the west.

Mostly on point, but I’d like to point out that no model is “more accurate.” Each has its wins and losses.

 

[Rogifan]

Yes, it’s fairly common for hurricanes to take pretty wild turns, actually. Hurricanes are fairly shallow in the atmosphere, and it’s really easy for other features to “steer” them, and sometimes the interactions are really hard to predict. In this case, the interactions are dominated by a high-pressure system to Dorian’s north, the strength/size of which was seemingly underestimated by model analyses. That’s why some models are now backtracking to the west a bit as they begin to account for observations indicating that the ridge is a little bit stronger/larger than first thought.

Even for a possible car 5 hurricane? The NHC cone/track seems to be pinning it all on a sharp turn north after it lashes the Bahamas. I’m wondering what is giving them confidence that will happen?

 

[jonblatho]

Even for a possible car 5 hurricane? The NHC cone/track seems to be pinning it all on a sharp turn north after it lashes the Bahamas. I’m wondering what is giving them confidence that will happen?

Yes; in fact, the size of the storm would matter more than the wind speed (and there’s not a 1:1 relation between the two). Also, keep in mind that the NHC hasn’t updated its forecast since this afternoon (the 5 PM EDT advisory) and won’t update it again until 11 PM EDT. I’d strongly encourage reading the discussion for their latest full advisory for more details on their thinking, but do keep in mind that it’s not necessarily based on the most current information available.

 

[Rogifan]

Yes; in fact, the size of the storm would matter more than the wind speed (and there’s not a 1:1 relation between the two). Also, keep in mind that the NHC hasn’t updated its forecast since this afternoon (the 5 PM EDT advisory) and won’t update it again until 11 PM EDT. I’d strongly encourage reading the discussion for their latest full advisory for more details on their thinking, but do keep in mind that it’s not necessarily based on the most current information available.

Good to know. Btw this weather guy I follow on Twitter (crankywxguy) now seems a bit skeptical of the models jumped east narrative. And he’s not usually one in the business of hyping anything. My guess is it won’t be until tomorrow afternoon/evening when we really know if this north and then eastward turn is legit.

https://twitter.com/crankywxguy/status/1167969021838278668?s=21

 

[jonblatho]

Good to know. Btw this weather guy I follow on Twitter (crankywxguy) now seems a bit skeptical of the models jumped east narrative. And he’s not usually one in the business of hyping anything. My guess is it won’t be until tomorrow afternoon/evening when we really know if this north and then eastward turn is legit.

https://twitter.com/crankywxguy/status/1167969021838278668?s=21

I follow him too — a good follow.

Yes, the NHC is usually cautious to avoid “chasing the models.” We pay them to perform value-added services for a reason — they’re able to decide which model’s (if any!) solution they believe is most suitable, since they have brains and models, for all their successes, don’t. NHC tends to lag behind changes in models’ solutions because they’re there to take a skeptical eye to them and produce the best forecast they know how for their customers.

We’ll see what happens with the 11 PM advisory here in about an hour. I suspect we’ll see them shift the track back to the west some.

 

[Rogifan]

I follow him too — a good follow.

Yes, the NHC is usually cautious to avoid “chasing the models.” We pay them to perform value-added services for a reason — they’re able to decide which model’s (if any!) solution they believe is most suitable, since they have brains and models, for all their successes, don’t. NHC tends to lag behind changes in models’ solutions because they’re there to take a skeptical eye to them and produce the best forecast they know how for their customers.

We’ll see what happens with the 11 PM advisory here in about an hour. I suspect we’ll see them shift the track back to the west some.

This probably sounds silly but I pay attention to the big guns on TWC - Mike Seidel and Jim Cantore. If they’re still reporting from Florida tonight/tomorrow then Florida is not out of it by a long shot. There was a rumor Cantore was heading to South Carolina but apparently he’s in Stuart, Florida right now.

 

[jonblatho]

I follow him too — a good follow.

Yes, the NHC is usually cautious to avoid “chasing the models.” We pay them to perform value-added services for a reason — they’re able to decide which model’s (if any!) solution they believe is most suitable, since they have brains and models, for all their successes, don’t. NHC tends to lag behind changes in models’ solutions because they’re there to take a skeptical eye to them and produce the best forecast they know how for their customers.

We’ll see what happens with the 11 PM advisory here in about an hour. I suspect we’ll see them shift the track back to the west some.

11 PM advisory just in. Dorian stays at 150 mph and, as of now, they’re mostly sticking to the track (with some small modifications related to timing and not position).

 

[Rogifan]

11 PM advisory just in. Dorian stays at 150 mph and, as of now, they’re mostly sticking to the track (with some small modifications related to timing and not position).

NHC punted. Seems they’re being very conservative. I wonder what the 5am advisory will bring. On TWC Dr. Knabb did mention some of the models shifting west and it looks like Seidel and Cantore are still in Florida.

 

[jonblatho]

NHC punted. Seems they’re being very conservative. I wonder what the 5am advisory will bring. On TWC Dr. Knabb did mention some of the models shifting west and it looks like Seidel and Cantore are still in Florida.

They’re known for it, often to the chagrin of many armchair meteorologists on Twitter. From a communications perspective, when communicating hazards with a hurricane, it is always easier to scale up than scale down so that you don’t end up “crying wolf.”

In this case, much of Florida’s Atlantic coast remains within the cone, and there’s still plenty of time. Folks in the cone along Florida’s Atlantic coast should absolutely be making preparations and listening closely to their local National Weather Service office, the National Hurricane Center, and local authorities for more details as they make their preparations and decisions. Prepare for the worst, hope for the best.

You’d be amazed at how many people are expressing frustration that the NHC isn’t running with a single dropsonde observation of 155 kt (≈ 178 mph) winds at the surface to make Dorian a Category 5. There are multiple reasons to discount that observation as being unrepresentative of the storm’s maximum 1-minute sustained surface wind speed, which is the wind speed you see associated with the storm, but it seems some people really want this thing to be a Category 5.

Edit: 2 AM EDT advisory in. No forecast update as it’s an intermediate advisory. NHC is sticking to its guns at 150 mph.

 

[Rogifan]

So no real change with the 5am update, NHC left it as a cat 4 storm. I see some are suggesting the storm might not stall over the Bahamas as long as predicted. That would be good for the Bahamas but then I think it brings Florida back into play? Apparently the NHC did say the storm hitting the Florida coast is a ‘distinct possibilty’. And tropical storm watches now posted for areas closer to Miami.

 

[heyyitssusan]

I’m on the east coast of FL. Thank goodness we aren’t getting a direct hit like they intended at first. Still going to get those winds and rain.

 

[genomez]

I'm in SE FL and none of us are letting our guard down. We are hoping for the "turn" but are prepared for it not to.

 

[jonblatho]

I’m on the east coast of FL. Thank goodness we aren’t getting a direct hit like they intended at first. Still going to get those winds and rain.

You’re far from being out of the woods yet. I’d still prepare for the worst case — the price of being wrong, and the chance of being wrong, are just too high on this one, and you only have so much time.

 

[Rogifan]

I'm in SE FL and none of us are letting our guard down. We are hoping for the "turn" but are prepared for it not to.

Greg Postel from The Weather Channel just tweeted wind gusts of over 200 MPH. He says he’s never seen that before. Everyone on the Florida east coast should be prepared. Just a slight change in the track and it’s disaster.
https://twitter.com/GregPostel/status/1168166270312820736?s=20

My thoughts are with you. Be safe. Fingers crossed this stays out at sea.

 

[jonblatho]

A special update from the NHC at 9:30 AM EDT, with a full advisory on the way at 11 AM, puts Dorian at a powerful Category 5 hurricane with maximum sustained winds of 175 mph.

Incredible. Thoughts for the northwest Bahamas especially right now, though I also fear what will happen should it get too close to Florida or make landfall there, as both certainly remain possible.

 

[Rogifan]

You’re far from being out of the woods yet. I’d still prepare for the worst case — the price of being wrong, and the chance of being wrong, are just too high on this one, and you only have so much time.

Mandatory evacuations now for Palm Beach and Martin counties. Martin includes the city of Stuart where TWC’s Jim Cantore has been camped out.

EDIT: 11 am update. Looks like it slowed 1 mph. But winds increased and pressure dropped. This is one sick storm.

11:00 AM EDT Sun Sep 1
Location: 26.5°N 76.8°W
Moving: W at 7 mph
Min pressure: 913 mb
Max sustained: 180 mph

 

[MacNut]

Winds up to 180, now classified as the strongest hurricane in modern record.

 

[jonblatho]

Mandatory evacuations now for Palm Beach and Martin counties. Martin includes the city of Stuart where TWC’s Jim Cantore has been camped out.

EDIT: 11 am update. Looks like it slowed 1 mph. But winds increased and pressure dropped. This is one sick storm.

11:00 AM EDT Sun Sep 1
Location: 26.5°N 76.8°W
Moving: W at 7 mph
Min pressure: 913 mb
Max sustained: 180 mph

Also important to note that the NHC also placed coastal east-central Florida under a hurricane watch with this advisory.

 

[MacNut]

Per the NHC,
Maximum sustained winds have increased to near 180 mph (285 km/h)
with higher gusts. Dorian is a extremely dangerous category 5
hurricane on the Saffir-Simpson Hurricane Wind Scale. Some
fluctuations in intensity are likely, but Dorian is expected to
remain a powerful hurricane during the next few days.

Dorian has grown larger in size. Hurricane-force winds extend
outward up to 45 miles (75 km) from the center and tropical-storm-
force winds extend outward up to 140 miles (220 km). Ham radio
reports indicate that Hope Town in the Abacos just reported wind
gust to 100 mph.

The minimum central pressure measured by both NOAA and Air Force
reconnaissance plane was 913 mb (26.96 inches).

 

[jonblatho]

Winds up to 180, now classified as the strongest hurricane in modern record.

They say it’s the strongest hurricane in modern records “for the northwestern Bahamas,” which is an important distinction. There have been stronger hurricanes both in pressure and wind speed.