ATL: DORIAN - Post-Tropical - Discussion

[1900hurricane]

For those wondering, 1005 mb plugged into KZC (rOCI version) with some of the other best track stuff gets me 41.9 kt, right in line with the 42 kt found by SFMR on the first pass.

[AxaltaRacing24]

Barely a TS... oops

Ok GFS

it's not "barely a ts"

[wxman57]

Been very busy all day. Been working 8 days straight. Another 8 to go, at least. Recon indicates that Dorian barely has a circulation. Looks more like an open wave. SW quadrant winds are all blowing away from the center (N-NNE). That's not what you'd expect in a well-organized TS. Winds should be from the WNW-NW in that quadrant.

Someone wanted a surface map? Winds howling at 20 kts just 15 miles from Dorian's center. There are some 40-45 kt winds NE of the center. Not a lot of surface convergence, though. I have Dorian reaching the SE FL coast Sunday morning, but with a tremendous amount of uncertainty as to whether it can survive in the East Caribbean. Very dry air to its north and west, though not too bad to the NE-SE.

Note, Barbados just reported a sustained wind of 24 kts with a gust to 39 kts as the storm nears:

TBPB 270000Z 05024G39KT 9999 -RA SCT010CB SCT012 BKN032 26/23 Q1009 TEMPO TSRA SHRA
TBPB 262300Z 06018G30KT 9999 VCTS -RA FEW010CB BKN012 BKN032 27/24 Q1010 NOSIG
TBPB 262200Z 06020KT 9999 VCTS -RA FEW010CB SCT014 BKN032 27/23 Q1010 NOSIG
TBPB 262100Z 06022KT 8000 SHRA SCT010CB SCT014 27/23 Q1010 NOSIG
TBPB 262000Z 05018KT 9999 VCSH SCT014 SCT032 27/24 Q1010 NOSIG

[GCANE]

Max winds are more likely directly north of the CoC

[SFLcane]

Been very busy all day. Been working 8 days straight. Another 8 to go, at least. Recon indicates that Dorian barely has a circulation. Looks more like an open wave. SW quadrant winds are all blowing away from the center (N-NNE). That's not what you'd expect in a well-organized TS. Winds should be from the WNW-NW in that quadrant.

Someone wanted a surface map? Winds howling at 20 kts just 15 miles from Dorian's center. There are some 40-45 kt winds NE of the center. Not a lot of surface convergence, though. I have Dorian reaching the SE FL coast Sunday morning, but with a tremendous amount of uncertainty as to whether it can survive in the East Caribbean. Very dry air to its north and west, though not too bad to the NE-SE.

http://wxman57.com/images/DorianSfc.JPG

Have it reaching SFL coast as a batch of clouds or a formidable tc?

[Bocadude85]

Hope everyone in the path of Dorian stays safe, seems like those of you in Florida will need to watch him closely in the coming days.

[Hammy]

Based on recon data it seems GFS had the right idea with dissipation in a few days after all.

[MGC]

Been very busy all day. Been working 8 days straight. Another 8 to go, at least. Recon indicates that Dorian barely has a circulation. Looks more like an open wave. SW quadrant winds are all blowing away from the center (N-NNE). That's not what you'd expect in a well-organized TS. Winds should be from the WNW-NW in that quadrant.

Someone wanted a surface map? Winds howling at 20 kts just 15 miles from Dorian's center. There are some 40-45 kt winds NE of the center. Not a lot of surface convergence, though. I have Dorian reaching the SE FL coast Sunday morning, but with a tremendous amount of uncertainty as to whether it can survive in the East Caribbean. Very dry air to its north and west, though not too bad to the NE-SE.

http://wxman57.com/images/DorianSfc.JPG

Have it reaching SFL coast as a batch of clouds or a formidable tc?

Million dollar question....

[GCANE]

Looks like Barbados dodged a bullet

[wxman57]

Have it reaching SFL coast as a batch of clouds or a formidable tc?

Yes.

[SFLcane]

Have it reaching SFL coast as a batch of clouds or a formidable tc?

Yes.

Yes what? Lol

[Kingarabian]

Recon still needs to sample the whole system, but it's likely with all of what Wxman57' explained that the NHC might have the winds too high.

[wxman57]

Have it reaching SFL coast as a batch of clouds or a formidable tc?

Yes.

Yes what? Lol

One of those two options. I have it as a moderate TS but my confidence that it will survive another 48 hrs is very low. Very little surface convergence. Lots of dry air in its path. Barbados will be a good gauge as to its true winds, as the island will be passing right through Dorian's max wind area NE of the center shortly. I suspect obs will be well under 50 kts. Maybe closer to 35 kts. Note that the obs reported are 2-min winds. There's a small multiplier to convert standard obs to 1-min. I think 1.04 or 1.1, or similar. Had to explain that to lawyers in a court case a few years ago.

[Hypercane_Kyle]

This storm is quickly turning into one of the more obnoxious storms to track, lol.

[CrazyC83]

I agree they were likely too high. 40 kt seems the best estimate. Did it weaken or was it overestimated all along though? I don't remember any ASCAT passes.

[toad strangler]

Have it reaching SFL coast as a batch of clouds or a formidable tc?

Yes.

That’s a whole lot more aggressive from 57 than the past couple days

[wxman57]

Recon still needs to sample the whole system, but it's likely with all of Wxman57' explained that the NHC might have the winds too high.

The NHC will always err on the side of caution. They're an excellent group of forecasters, I know them all. One might be a tad overly-aggressive with intensity. They won't likely reduce their winds with the storm heading for the islands, no matter what recon indicates. They have their mission, we have ours. We're not concerned about the reaction of the general public, as they don't see our forecasts.

[Kingarabian]

I agree they were likely too high. 40 kt seems the best estimate. Did it weaken or was it overestimated all along though? I don't remember any ASCAT passes.

Overestimated most likely due to some faulty microwave analysis. I think an ASCAT pass earlier today only had about 30-35kt winds.

[AdamFirst]

Looks can certainly be deceiving.

[wxman57]

I agree they were likely too high. 40 kt seems the best estimate. Did it weaken or was it overestimated all along though? I don't remember any ASCAT passes.

Overestimated most likely due to some faulty microwave analysis. I think an ASCAT pass earlier today only had about 30-35kt winds.

Such a tiny system with the radius of max winds maybe 10 miles out may be hard for ASCAT to resolve.