Hurricane Dorian

[summer blizzard]

Invest 99L has become Tropical Depression 5, forecast to become a Hurricane within 96 hours. Track right now takes it through the Lesser Antilles before a likely recurve towards Haiti. 

DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of newly formed Tropical Depression Five was located near latitude 10.4 North, longitude 47.9 West. The depression is moving toward the west near 12 mph (19 km/h) and this general motion is expected to continue today. A turn toward the west-northwest is forecast on Sunday, and that motion is expected to continue through Tuesday. On the forecast track, the tropical cyclone is expected to be near the central Lesser Antilles on Tuesday. Maximum sustained winds are near 35 mph (55 km/h) with higher gusts. Gradual strengthening is forecast during the next few days, and the depression is forecast to become a tropical storm later tonight or on Sunday. The estimated minimum central pressure is 1010 mb (29.83 inches).

Edited August 28, 2019 by Lauren

[Lauren]

And we have Dorian! I'm sure Dr Cox will have something to say about this.

[summer blizzard]

Dorian now forecast to be at or near hurricane strength when it reaches the Lesser Antilles.

NHC now also note the potential for rapid intensification.

Does anybody have the SHIPS probabilities?

[summer blizzard]

Have just checked SHIPS, 33% chance that Dorian will be a 100KT cane when it reaches the islands on Tuesday (115mph - cat 3).

[summer blizzard]

Not a proper eye but indications that a proper core is now starting to form.

[Lauren]

The recon flights are on their way.

[summer blizzard]

50mph, 1003mb.

 

[summer blizzard]

While it may not survive that long it is interesting to note that the 0z GFS ensembles strongly suggest a southern Florida hit down the line albeit at what strength i could not say.

 

[summer blizzard]

Both the old GFS6z and 0z Euro hit Puerto Rico instead and then Florida.

[summer blizzard]

1002mb, 60mph. 

Nhc noting that a low and mid level eye are now forming and as such hurricane warnings have been issued for the Windward Islands and St Lucia.

 

 

[Lauren]

Is that Dorian you can see approaching to the right?

[summer blizzard]

1 hour ago, Lauren said:

Is that Dorian you can see approaching to the right?

Yes and it looks like Dorian has popped an eye on Dvorak and Infra-red. Should pass close.

[Zephyr]

Eye starting to become a bit more defined and still intensifying on latest loop 

 

https://www.tropicaltidbits.com/sat/satlooper.php?region=05L&product=ir

Edited August 26, 2019 by Zephyr

[Allseasons-si]

4 minutes ago, Zephyr said:

Eye starting to become a bit more defined and still intensifying on latest loop 

 

https://www.tropicaltidbits.com/sat/satlooper.php?region=05L&product=ir

That's quiet a sig development in a few hours.

Edited August 26, 2019 by Allseasons-si

[summer blizzard]

Old GFS strongest this morning. 970mb into Florida.

Currently holding steady as it hits the islands.

[karyo]

In the latest update, Dorian has 50mph sustained winds and the pressure is a bit higher at 1005mb.

Some differences in the models, the UKMO and ICON take Dorian to southern Florida and then possibly the Gulf of Mexico. The GFS and ECM hardly make anything of the system. 

The NHC take Dorian on a slightly more northerly track than yesterday. They expect her to pass between Puerto Rico and Hispaniola, still making landfall somewhere in eastern Hispaniola but crucially avoiding the high mountains in the centre of the island.

[summer blizzard]

It looks like the old center attempting to form an eye yesterday has died and relocated overnight. The cloud pattern is now circular and there are strong winds in the NE quad but the center is broad and barely closed.

Its hard to say with these storms whether it stays like this and opens up or whether this new center tightens.

[karyo]

The updated ICON is good news for Hispaniola as the storm tracks further north. Southern Florida gets a direct hit though!

[Zephyr]

Seems to be a good spread on the intensity guidance although the majority keeping it as a TS

[summer blizzard]

Center has reformed further north and is much better defined. Models now miss Haiti and hit Puerto Rico before heading for Florida.

Globals currently going for cat 2 ish at landfall however the UKMO and other models do suggest that it could be undergoing rapid intensification around landfall. 

 

[summer blizzard]

GFS18z new and old has good news and bad news.

The good news is that they love the center relocation and go for full on rapid intensification. New GFS drops to 962mb while the old GFS is the first major operational to go cat 5 at 920mb.

The bad news (possibly strength related) is that they both recurve just offshore of Florida and hug the coast before going out to sea (up side is we get our first proper recurve influence).

[karyo]

All the models now go for the much stronger hurricane scenario partly thanks to the more northerly track. This means that Hispaniola escapes and Dorian doesn't weaken due to the mountainous terrain of the island.

Then there is a difference in the track. Most models still take her to Florida. However the gfs continues to show a recurve northwards which spares Florida. The ECM is the opposite as the storm hits the east coast of Florida, then the west and eventually it even impacts the Carolinas. (triple whammy).

[summer blizzard]

Recon have found 81mph at flight level and an open eyewall so it will likely get upgraded to 70mph at 2pm.

Also looks north east of forecast position, it may well miss Peurto Rico.

[knocker]

Tropical Storm Dorian Public Advisory

Quote

DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of Tropical Storm Dorian was located near latitude 17.5 North, longitude 64.5 West. Dorian is moving toward the northwest near 13 mph (20 km/h), and this motion is expected to continue for the next day or two. On this track, Dorian should move near the U.S. and British Virgin Islands and then continue over the open Atlantic well east of the southeastern Bahamas. Maximum sustained winds have increased to near 70 mph (110 km/h) with higher gusts. Dorian is forecast to become a hurricane later today and continue strengthening during the next few days over the Atlantic waters. Tropical-storm-force winds extend outward up to 80 miles (130 km) primarily to the east of the center.

https://www.nhc.noaa.gov/text/refresh/MIATCPAT5+shtml/281459.shtml

Edited August 28, 2019 by knocker

[Mr Frost]

 

Edited August 28, 2019 by Mr Frost