ATL: Tropical Depression Dolly

[Hurricanewatcher2007]

Prediction time when do you think we will see Hurricane Dolly? 11am 5pm or 11pm?

I say 5pm unless its done with a Special between 11 and 5

[JtSmarts]

I'm still concerned about seeing shift much more northward at any time. Not saying it'll happen nor do I have any evidence to support this.

On another note, if she does continue on the same path towards Brownsville area and maintains speed of 7mph I've figured she would make landfall around 10pm Central Wednesday night. Once again that is if my calculations are right.

That looks right on point with the NHC forecast since they expect her to already be inland by 1:00 CDT, as a 85mph hurricane still. Good Job!

[americanrebel]

I will go with 11 am, because in the next few hours with daytime warming, she will be ripe for explosion.

[Hurricanewatcher2007]

I will go with 11 am, because in the next few hours with daytime warming, she will be ripe for explosion.

But with tropical cyclones convection is at its worst during the day so just because the sun is coming up doesn't mean anything positive for Dolly and in fact may mean something negative for her.

[KWT]

The cycles probably won't matter very much for Dolly now given its got a pretty established convective set-up now and the feeder band has set-up.

[americanrebel]

I will go with 11 am, because in the next few hours with daytime warming, she will be ripe for explosion.

But with tropical cyclones convection is at its worst during the day so just because the sun is coming up doesn't mean anything positive for Dolly and in fact may mean something negative for her.

Sorry, but Hurricanewatcher where are you from and how old are you? Not to sound rude, but some of the most prime time for explosion is at Sunrise and Sunset. I have seen it many times over. Have been following Hurricanes almost all my life living in South Louisiana.

[americanrebel]

Looks like recon is already trying to figure out how far out her winds are, they just did some observations of the far out arm of Dolly and found 15 kt surface winds.

[Hurricanewatcher2007]

Well I don't know about right at sun rise and sun set but during the day convection is at its worst. And then you have storms like Rita in 2005 and Bertha this year that went through RIC during the day so I guess it really depends on how mature the system is and how well established it is.

[Matt-hurricanewatcher]

Well I don't know about right at sun rise and sun set but during the day convection is at its worst. And then you have storms like Rita in 2005 and Bertha this year that went through RIC during the day so I guess it really depends on how mature the system is and how well established it is.

To a weak system like a distrabance, wave, or weak depression that is true. You have at day near land it warms forming convection on land, rising air. But at night you have the air moving off land in rising over the ocean, because the ocean is much warmer then the land at night.

At day you have a stable layer at the midlevels that develops, or a "invasion" that caps convection to develop. This is during the day. Also if the system is close to land the land convection don't allow the convection forming from the LLC to develop.

On the other hand a developed system don't really care to much about this. Look at Charley 2004, Katrina 2005.

[KWT]

Yeah really it doesn't matter to much for a developed system and Dolly is quickly becoming that way...
Has anyone got Microwave imagery so we can see if its gaining any eyewall?

[Nimbus]

Its hard to be sure of center motion on IR imagery but it looks like Dollys forward speed slowed overnight.
If this latest convection bloom is the start of RI and there is a slower forward speed, those factors may be signaling a track shift back towards the WNW or even NW.

Rapidly intensifying storms north of 20 have been known to turn poleward and stall even with fairly strong ridging in place so that can make forecasting difficult.

The HWRF and GFS both show a jog to the NW late in the track before shifting the track back west again after landfall.

[Hurricanewatcher2007]

Its hard to be sure of center motion on IR imagery but it looks like Dollys forward speed slowed overnight.
If this latest convection bloom is the start of RI and there is a slower forward speed, those factors may be signaling a track shift back towards the WNW or even NW.

Rapidly intensifying storms north of 20 have been known to turn poleward and stall even with fairly strong ridging in place so that can make forecasting difficult.

The HWRF and GFS both show a jog to the NW late in the track before shifting the track back west again after landfall.

It did slow according to the NHC on the 5am package its now moving at 15mph. But between the last 2 center fixes it traveled about 14 miles in about 2 hours so that would be a speed of about 7 mph

[KWT]

Yep the NHC works on averages over a period of time but we should see the foward speed estimate slow right down given it hasn't really moved all that much at least according to IR.

Nimbus, that may well be possible if it does decide to strengthen quite rapidly and become a cat-2/3, stronger storms do tend to have a little better pull to the north.

[Meso]

Rather old image, not sure how often it updates

Oh and few posts up, that's 'Inversion"

[americanrebel]

Its hard to be sure of center motion on IR imagery but it looks like Dollys forward speed slowed overnight.
If this latest convection bloom is the start of RI and there is a slower forward speed, those factors may be signaling a track shift back towards the WNW or even NW.

Rapidly intensifying storms north of 20 have been known to turn poleward and stall even with fairly strong ridging in place so that can make forecasting difficult.

The HWRF and GFS both show a jog to the NW late in the track before shifting the track back west again after landfall.

This is what I have been forecasting for the last 2 days, not many people have kept their ideas of what she is going to do consistently over the last 2 days, but I have been saying this for the past 2 days, and I will continue to say it. I have no problem having egg on my face if I am wrong.

This is totally unofficial, no scientific evidence is behind what I am about to say.

I think Dolly will either continue to slow down or completely stall out, while she continues to stack up and whenever she decides to start moving again it will be in a more Northernly motion than NW, since the Uppler level winds is more supportive of a Northernly turn. If her CDO continues to grow as it is, this thing could get very large and basically pull a Rita.

[KWT]

So still a little messy then Meso, still I think if does keep up that CDO that it has right now and pressure keeps dropping its only a matter of time before it does develop an even better inner core.

Also you can really see the structure of Dolly well here, looks like its slowly improving still:

http://www.ssd.noaa.gov/goes/flt/t2/sloop-bd.html

americanrebel, it will be interesting to see what the direction will be when we get Vis imagery later.

[Smurfwicked]

But a slower moving hurricane vs one moving faster of equal strength would mean a less intense storm surge correct?

[Hurricanewatcher2007]

I don't think so. I could be wrong but I think the slower the speed the more time it has to build up the storm surge

[KWT]

I believe its the size of the system that has a big role in storm surge as well as strength, so if you can a powerful hurricane develop thats large then it will have a large storm surge, hence Katrina...

[HURAKAN]

Look at that band!!!