ATL : TROPICAL DEPRESSION IDA

[Aric Dunn]

Still shooting for that extra tropical stuff... alrighty then ..lol

[Evil Jeremy]

So, do you guys think it is likely that Ida will become extra tropical as is currently forecast, or remain tropical through landfall?

[Aric Dunn]

So, do you guys think it is likely that Ida will become extra tropical as is currently forecast, or remain tropical through landfall?

I dont see it transitioning if she becomes a hurricane again.. That and she is still faster than the forecast models thus far... if she gets far enough north the trough should not leave her behind.. to transition.. just have to wait and see

[Derek Ortt]

Just want to point out that some of the non GFS models do show a small anti-cyclone over the system and not shear once in the GOM

Just something to consider. I suspect we wil see an outflow pattern that supports a cat 1

[StarmanHDB]

So, do you guys think it is likely that Ida will become extra tropical as is currently forecast, or remain tropical through landfall?

The way this season went, the one thing that is certain is that we're going to get some rain.

[NEXRAD]

So, do you guys think it is likely that Ida will become extra tropical as is currently forecast, or remain tropical through landfall?

If I were making a wager, I'd bet on Ida becoming a hybrid or extra-tropical system as indicated by the TPC. The models seem to hint at this, too. The GFDL, for example, expands Ida's wind field to something massive. It usually does that for transitioning systems. Meanwhile, jet energy aloft coupled with divergence along a SE-ward moving frontal boundary all look promising for a system that undergoes classic late season Gulf of Mexico tropical to extra-tropical transition.

- Jay
South Florida

[wzrgirl1]

what is the difference between tropical and extratropical...is it the core is cooler or something like that?

[ozonepete]

Well now I'm really intrigued on how this pans out. If the forecast now has the center of Ida abreast of Tampa at 7PM on Tuesday AND extratropical, then why would it recurve? If it has become extratropical and is entangled with the front and 500mb trough, why wouldn't it get carried by the 500mb winds and just ride up the front across Florida and out to sea? It's timing and positioning in relation to the digging trough and front are becoming the whole story.

[NEXRAD]

what is the difference between tropical and extratropical...is it the core is cooler or something like that?

Yes. A tropical cyclone has a warm core whereas an extratropical has a cold core low. Hybrid systems usually exhibit tropical features near the surface and non-tropical aloft. On satellite you can recognize a tropical system transitioning to an extra tropical storm by the displacement of convection and cold cloud tops north and east of the circulation, which eventually becomes almost fully exposed (sometimes it does) as the transition becomes completed.

- Jay
South Florida

[Aric Dunn]

Well now I'm really intrigued on how this pans out. If the forecast now has the center of Ida abreast of Tampa at 7PM on Tuesday AND extratropical, then why would it recurve? If it has become extratropical and is entangled with the front and 500mb trough, why wouldn't it get carried by the 500mb winds and just ride up the front across Florida and out to sea? It's timing and positioning in relation to the digging trough and front are becoming the whole story.

thats a good point and im not sure what models they are basing this on clearly not the dynamical models cause they do not hint at extra tropical .. gfs slightly does more so and the nogaps merges it with that system in the BOC .. but looking at the temp profiles in the gfs I dont see much to indicate that but oh well.. maybe they are just betting on it.. lol

[wzrgirl1]

Does that mean the system won't be as potent if it turns extratropical? Does it still have a center of circulation? I guess not if it's exposed. Thanks for answering me NEXRAD. Looking intently at this thing.

[ozonepete]

Well now I'm really intrigued on how this pans out. If the forecast now has the center of Ida abreast of Tampa at 7PM on Tuesday AND extratropical, then why would it recurve? If it has become extratropical and is entangled with the front and 500mb trough, why wouldn't it get carried by the 500mb winds and just ride up the front across Florida and out to sea? It's timing and positioning in relation to the digging trough and front are becoming the whole story.

thats a good point and im not sure what models they are basing this on clearly not the dynamical models cause they do not hint at extra tropical .. gfs slightly does more so and the nogaps merges it with that system in the BOC .. but looking at the temp profiles in the gfs I dont see much to indicate that but oh well.. maybe they are just betting on it.. lol

lol we could all toss a coin right now...

[Aric Dunn]

Well now I'm really intrigued on how this pans out. If the forecast now has the center of Ida abreast of Tampa at 7PM on Tuesday AND extratropical, then why would it recurve? If it has become extratropical and is entangled with the front and 500mb trough, why wouldn't it get carried by the 500mb winds and just ride up the front across Florida and out to sea? It's timing and positioning in relation to the digging trough and front are becoming the whole story.

thats a good point and im not sure what models they are basing this on clearly not the dynamical models cause they do not hint at extra tropical .. gfs slightly does more so and the nogaps merges it with that system in the BOC .. but looking at the temp profiles in the gfs I dont see much to indicate that but oh well.. maybe they are just betting on it.. lol

ok well the nHC says most of the models shows transition at 96 hours.. ?? but ok i'll take their word on the model analysis.. lol

[ROCK]

From what I understand it is a Upper Level Trough moving across TX and into the western Gulf on Sunday that develops the height falls and eventually the low pressure develops over the western Gulf on Sunday. This feature is what most of the models join together with Ida over the central Gulf.

There is that ULL moving into Baja that can be added to the equation. I dont know how that is going to play out. Also 96E is being drawn into the circulation of IDA....tremendous amount of moisture here...

[Aric Dunn]

ok well be back tomorrow for some more fun and excitement .. lol

[ericinmia]

Just remember that the NHC has never been great at Intensity... Better than most anyone else, but still not great.

Just as an example wasn't Wilma progged for a while to be ripped apart? I know many things can't be compared... but it's worth stating.

I'm curious to wait and see what all occurs. (Where's the fast forward button? lol)
-Eric

[ozonepete]

Does that mean the system won't be as potent if it turns extratropical? Does it still have a center of circulation? I guess not if it's exposed. Thanks for answering me NEXRAD. Looking intently at this thing.

Not necessarily. They still have a significant center of circulation but the strongest winds are not around the center but further away. One example is Hurricane Hazel in 1954. It hit the NC/SC border in mid October as a cat 4. A REALLY strong cold front and trough with surface temps in the 40s moved in from the west at the same time. HAzel got so energized as it went extratropical that it blew trees down through all of DC, PA and southern Canada.

[wzrgirl1]

yup who knows what we'll see in the morning....thanks goodness for the shear in a few days

[NEXRAD]

Does that mean the system won't be as potent if it turns extratropical? Does it still have a center of circulation? I guess not if it's exposed. Thanks for answering me NEXRAD. Looking intently at this thing.

Hi, Wzrgirl1.

I posted something in a reply to a post in the "talking tropics forum" that I think summarizes the differences in tropical cyclone threats and "potency" versus hybrid and extra-tropical lows. I'll cross post the text here, hoping not to equally cross the moderators! The short answer, though, is "potent" depends on your definition.

Tropical storms and hybrid storms both bring potential for hazardous and damaging weather, but in somewhat different ways. A true tropical storm has the potential to strengthen more than (most) hybrid storms. This isn't to say that hybrid storms cannot become quite powerful. For example, non-tropical Nor'Easters have produced hurricane-force winds at times and the Superstorm of 1993 produced hurricane force wind gusts across most of Florida. Another difference between the two types of systems is that a true tropical storm/hurricane will tend to have its strongest winds concentrated close to the storm center. A hybrid system typically will have its strongest winds located well away from the center. North Atlantic hybrid systems usually have their strongest winds located well north and east of the given storm's center. Because hybrid storms usually have much larger areas of high winds than do most tropical cyclones, hybrid storms can still generate dangerous seas and possible storm surge. The storm surge potential, however, is highly dependent on the exact storm, its track, and its intensity. Finally, there is evidence to support that hybrid tropical systems may be much more dangerous in terms of tornado potential than typical tropical storms. See Bart Hagemeyer's (NWS Melbourne) research for some literature to support this.

To conclude... a hybrid system won't likely be as devastating as a direct hit by a major hurricane, but the effects in terms of wind and even surge can be very similar to any tropical storm (or in some cases even a weak hurricane). The tornado threat, though, may be greater with a hybrid system according to some studies.

- Jay
South Florida

[ozonepete]

ok well be back tomorrow for some more fun and excitement .. lol

see you tomorrow