ATL: DORIAN - Post-Tropical - Discussion

[underthwx]

I wish Dorian would either dissipate, or rapidly move away, out to sea, I am worried for yall in the impacted areas, waiting and watching endlessly with this cyclone. I trust all of you, that need to be prepared, have done so. I did not prepare for Harvey, I thought I knew better, and it cost me.

[wx98]

Pressure way up around 940 and the winds have come down. SFMR borderline Cat 2/Cat 3 based on the pass. FL still about 130 knots

[HDGator]

What are the conditions like along the Florida coastline?....are yall experiencing Tropical Storm level winds?

I'm in northern Palm Beach County and Dorian's center is 90nm due east of me according to doppler radar.
It's been a breezy morning with rain squalls coming through occasionally. We're seeing gusts of maybe ~20mph in the worst ones.
Other than that it's just a cloudy, breezy day.
It's hard to comprehend that this monster is less than 100 miles away absolutely destroying our neighbors in the Bahamas.
It gives me a really heavy heart to think of what we'll find when Dorian finally departs.

[NDG]

saved radar loop

https://i.imgur.com/MU5Hq0f.gif

Definitely looks like some dry air from the NW got into the COC this morning.

[1900hurricane]

Dorian has weakened a lot. May only be an entry level category 4 now based on the recon data.

[Highteeld]

I bet they go quite a bit higher than what SFMR shows for 2pm, just like what they did with Irma when its ERC was going on off the Cuban Coast.

[EquusStorm]

Would be hard to re-attain category five with weakening that substantial, probably not enough time before the turn. What a ridiculous peak we had though.

[NDG]

Pressure way up around 940 and the winds have come down. SFMR borderline Cat 2/Cat 3 based on the pass. FL still about 120 knots

Flight level winds at 129 knots is still at least a solid Cat 3

172500 2639N 07811W 6932 02840 //// +073 //// 219125 129 /// /// 05
$$

[hurricaneCW]

Nothing to stop Dorian from reintensifying once it starts moving again.

Weakening is due to upwelling/land interaction. I see cloud tops already getting colder.

[plasticup]

https://i.imgur.com/CuRoCko.gif

I do not see this supposed northerly component. Looks due West to me.

[aperson]

West side looks a little weak. I wonder if some dry air managed to work its way into the circulation as the footprint grew during eyewall replacement. The dry air is well sampled by the 12Z Key West sounding.

Yeah, it's definitely entraining a significant amount of continental dry air.

[Hurricane Andrew]

Nothing to stop Dorian from reintensifying once it starts moving again.

Weakening is due to upwelling/land interaction. I see cloud tops already getting colder.

Continental air flow, likely what caused it to weaken in the first place in addition to the factors you mentioned.

[cheezyWXguy]

Dorian's outflow is looking spectacular in all quadrants

Honestly this is what concerns me a bit. Environmental conditions are still incredibly favorable, the Gulf Stream isn’t far away, and despite signs of an Erc, Dorian’s structure is still very good. I am wondering what potential it has to restrengthen in the 24 hours or so between beginning to move and potentially threatening the coast. Are conditions expected to be less favorable during that time, or is the trough too far away to impose significant shear?

[supercane4867]

FL winds tend to be considerably higher than SFMR measured surface winds during the weakening phase. In the period of RI, stronger winds were likely to be mixed down to the surface resulting in much higher SFMR winds. That's why I won't completely discard the insanely high SFMR readings. 177kt could be legitimate and the peak intensity is indeed near 175kt

[xironman]

Pressure is way up, possibly only near 940mb per the recon.

Land and shallow water will definitely take its toll for that long. Currently crawling away to deeper water.

[drezee]

Ok...lets do this:
I will do calculations for direction, distance, and speed for the next few recon fixes....

Last Point Last night:
A. Time of Center Fix: 2nd day of the month at 3:28:50Z
B. Center Fix Coordinates: 26.59N 77.96W
First Point:
1720Z
26.83N 78.4W

Distance =31.8 miles
Azimuth: 301.51° True WNW

31.8 miles/ 13.8hrs = 2.3 mph

[wx98]

Pressure way up around 940 and the winds have come down. SFMR borderline Cat 2/Cat 3 based on the pass. FL still about 120 knots

Flight level winds at 129 knots is still at least a solid Cat 3

172500 2639N 07811W 6932 02840 //// +073 //// 219125 129 /// /// 05
$$

Yes I meant to say 130 knots I believe this is still a low end Cat 4.

[ConvergenceZone]

Since it's weakening faster than expected, I won't be surprised if it's just a tropical storm by the time is reaches the Carolina area late in the week, due to more shear etc that is expected.....

[toad strangler]

Finally a outer band shower that packed a mild punch in Port St Lucie

[ColdMiser123]

A shallower storm system will follow the low level flow more compared to a taller storm system, since upper level flow starts to have a larger effect on storm motion with a taller storm system.

A weaker Dorian now may actually imply a track slightly closer to the Florida coast, since low level flow will be out of the southeast on closest approach, while upper level flow will be out of the west.