ATL: DORIAN - Post-Tropical - Discussion

[HDGator]

Just an observation from Wellington, Florida which is west of west palm beach, in pbc. As of this afternoon, more houses have shutters up than do not. And more were out putting them up when we got home from dinner. So people are taking this storm seriously.

Just up a ways in Palm Beach Gardens, all of my neighbors that have/need to shutter had them up by tonight. I see everyone taking it seriously here.
Warms my heart.
Now let's send this thing OTS.

[eastcoastFL]

https://twitter.com/pppapin/status/1168376524120047617

models are likely fully underestimating the ridge pumping likely happening.

stay vigilant florida east coast !

Do you think the reason for that has anything to do with the unprecedented strength of this storm? The models seem to struggle with storms of this magnitude. The forecasting with Irma was pretty bad too.

[Aric Dunn]

https://twitter.com/pppapin/status/1168376524120047617

models are likely fully underestimating the ridge pumping likely happening.

stay vigilant florida east coast !

Do you think the reason for that has anything to do with the unprecedented strength of this storm? The models seem to struggle with storms of this magnitude. The forecasting with Irma was pretty bad too.

Yeah, ridge pumping is a real thing and purely modeled.

[Sanibel]

Core of Dorian edging in to Miami short range radar...

[decgirl66]

North Brevard County here (Titusville). I mentioned to my husband last night that no one in our neighborhood was putting up shutters/plywood....totally different story this afternoon! My husband has not left or boarded up for any storm for the last 45 years. He is getting plywood tomorrow (having a Home Depot employee as a daughter has it's perks!) and we have an evacuation plan in place if this storm doesn't make that north turn soon.

[1900hurricane]

Anyone have a fresh microwave image of Dorian?

[eastcoastFL]

models are likely fully underestimating the ridge pumping likely happening.

stay vigilant florida east coast !

Do you think the reason for that has anything to do with the unprecedented strength of this storm? The models seem to struggle with storms of this magnitude. The forecasting with Irma was pretty bad too.

Yeah, ridge pumping is a real thing and purely modeled.

It seems as if they take most Synoptics into consideration other than the strength and possibility of ridge pumping. Do they ever add that into the ensembles?

[rigbyrigz]

Commenters, model analysis, and NHC use the term "landfall" a lot right now. I have seen meteorological definitions that say it's when the center touches (crosses) land. but does that mean the center of the eye. or any part of the eye (the center of the storm)?

With the close proximity to coast, and the eye ( now 10 but was diameter 15 miles not long ago) possibly quite large, what is the consensus expert view on what exactly is meant by landfall regarding the eye?

From NHC... https://www.nhc.noaa.gov/aboutgloss.shtml

Landfall:
The intersection of the surface center of a tropical cyclone with a coastline. Because the strongest winds in a tropical cyclone are not located precisely at the center, it is possible for a cyclone's strongest winds to be experienced over land even if landfall does not occur. Similarly, it is possible for a tropical cyclone to make landfall and have its strongest winds remain over the water. Compare direct hit, indirect hit, and strike.

Thanks! Please correct me if I'm wrong, but this (to me) implies any part of the "surface center" (eye) touching land = LANDFALL. When we have these 15-20 miles wide diameter eyes, I would therefore take landfall to be when the eyewall basically passes. Many texts have differentiated eyewall crossing (= Direct Hit") as different from =LANDFALL. Thanks again for the cite, and sure its just semantics though 10 miles is a lot with Dorian's closeness, but how do you all interpret the NHC - same as me?

[eastcoastFL]

He’s definitely crawling along the southern edge of the nhc forecast line when viewing on sfwmd radar.


https://www.sfwmd.gov/weather-radar/cur ... conditions

[Highteeld]

pressure up to around 916. matches the warming clouds tops.

[ozonepete]

North Brevard County here (Titusville). I mentioned to my husband last night that no one in our neighborhood was putting up shutters/plywood....totally different story this afternoon! My husband has not left or boarded up for any storm for the last 45 years. He is getting plywood tomorrow (having a Home Depot employee as a daughter has it's perks!) and we have an evacuation plan in place if this storm doesn't make that north turn soon.

Good for you. You're doin' it right.

[SapphireSea]

Do you think the reason for that has anything to do with the unprecedented strength of this storm? The models seem to struggle with storms of this magnitude. The forecasting with Irma was pretty bad too.

Yeah, ridge pumping is a real thing and purely modeled.

It seems as if they take most Synoptics into consideration other than the strength and possibility of ridge pumping. Do they ever add that into the ensembles?

Ridge Pumping is kind of mis-worded. The outflow of the storm tends to suppress vorticity which can allow ridging to rebuild where there would be an upper low or trof. The synoptic scale forces that are going to erode the ridge would not be impacted by the outflow of Dorian. The actual fly in the ointment I think is that the trof energy may be too progressive, but if it catches it would likely mean an earlier sharper turn than forecasted. But, keep in mind it is a sensitive environment. Stalled storms are very unpredictable. The only saving grace is that in canada I can see the sharpening trough that will divert out to sea materialized and as strong or a little stronger than expected.

[KC7NEC]

He’s definitely crawling along the southern edge of the nhc forecast line when viewing on sfwmd radar.


https://www.sfwmd.gov/weather-radar/cur ... conditions

Based on Recon he is SOUTH of all the 00z Models......

[Sanibel]

Might be encountering continental air...That could produce unexpected weakening...

[J3r3my]

Link to South Florida Water Management District's radar with NHC forecast line overlayed will be interesting to follow

https://www.sfwmd.gov/weather-radar/cur ... conditions

I concur this is the easiest way to keep a level-headed track of the storm. At least for the non Pro Mets.

I'm in St Augustine, have been recently hit by Matthew and Irma, and I'm not liking the way this storm is rewriting the rules for what should be happening. I love the Abacos and hope all the good people have peace and hope in the coming days.

[cfl-gal]

Cat 5 tracking into an anti-cyclone.
Now I see the hot-pink donut.
That sick feeling when I thought this goes sub 900mb before all said and done, just came back to me.

https://i.imgur.com/D2AL092.jpg

What’s an anti-cyclone? First few results in a search mention calm weather.

I’m no pro or anything, but this is definitely not that.

[eastcoastFL]

Yeah, ridge pumping is a real thing and purely modeled.

It seems as if they take most Synoptics into consideration other than the strength and possibility of ridge pumping. Do they ever add that into the ensembles?

Ridge Pumping is kind of mis-worded. The outflow of the storm tends to suppress vorticity which can allow ridging to rebuild where there would be an upper low or trof. The synoptic scale forces that are going to erode the ridge would not be impacted by the outflow of Dorian. The actual fly in the ointment I think is that the trof energy may be too progressive, but if it catches it would likely mean an earlier sharper turn than forecasted. But, keep in mind it is a sensitive environment. Stalled storms are very unpredictable. The only saving grace is that in canada I can see the sharpening trough that will divert out to sea materialized and as strong or a little stronger than expected.

Thank you for the detailed explanation . Do they take this into consideration in any of the ensemble runs?

[1900hurricane]

 https://twitter.com/1900hurricane/status/1168392969063403520



 https://twitter.com/1900hurricane/status/1168393462179336192

[eastcoastFL]

He’s definitely crawling along the southern edge of the nhc forecast line when viewing on sfwmd radar.


https://www.sfwmd.gov/weather-radar/cur ... conditions

Based on Recon he is SOUTH of all the 00z Models......

I wonder how it lines up with the previous runs that called for a wsw dip before a landfall around broward/pb county line. It was just 48 hours ago that multiple models predicted that and not much has changed besides intensity

[Aric Dunn]

South of due west.. 265 ish for the last 5 plus hours..