ULL eatting up Arlene

[tailgater]

Looking at this mornings water vapor loop the Through to the west of Arlene has now become an ULL almost directly over her, if so she's toast.

[Steve]

She's not toast. In fact some of the models even slow her down just before landfall. I'm not sure why, but about 3 of them want to do it.

Steve

[Rainband]

could be why that burst of convection closer to the keys flared up. Maybe a new center will form or it's just shear induced..time as always will tell. Maybe the GFS weakening trend is right on. stranger things have happened.

[baygirl_1]

Slow her down? Oh my! Sounding more like Danny--- NO!!!! I hope not... we'll just have to wait and see.

[tailgater]

could be why that burst of convection closer to the keys flared up. Maybe a new center will form or it's just shear induced..time as always will tell. Maybe the GFS weakening trend is right on. stranger things have happened.

Radar out of KW doesn't show relocation but it sure looks like from sat. pics. Also would make it traverse cooler SST's but as you, say time will tell.

[hiflyer]

may i suggest that you can now see the llc and it has shifted east during the night and is located under the cdo.
http://wwwghcc.msfc.nasa.gov/GOES/goeseastconus.html

looks like eyw radar can only brush the east side of the llc at the end of their range.

[Stormcenter]

could be why that burst of convection closer to the keys flared up. Maybe a new center will form or it's just shear induced..time as always will tell. Maybe the GFS weakening trend is right on. stranger things have happened.

Shear induced is my thinking. You can still see the center pretty well on visible.

[Air Force Met]

Looking at this mornings water vapor loop the Through to the west of Arlene has now become an ULL almost directly over her, if so she's toast.

She's far from toast. Once she gets a little further north she will get into the NW quad of the upper low...and the outflow will be a little better.

Most certainly not toast.

[Brent]

Slow her down? Oh my! Sounding more like Danny--- NO!!!! I hope not... we'll just have to wait and see.

No... it may slow down but it won't stall like Danny. It's actually forecast to come in moving at 15 mph so a little slower would be closer to 10.

[CentralFlGal]

Looks like she's in a vice:

http://www.ssd.noaa.gov/PS/TROP/DATA/RT/nwatl-wv-loop.html

[tailgater]

Looking at this mornings water vapor loop the Through to the west of Arlene has now become an ULL almost directly over her, if so she's toast.

She's far from toast. Once she gets a little further north she will get into the NW quad of the upper low...and the outflow will be a little better.

Most certainly not toast.

If the LLC has relocated to the convection to the northeast of NHC latest position I could easily agree, but the dry air is entraining into the old LLC. IMHO I'm not doubting you, it's just something I thought I noticed.

[Air Force Met]

I'm not saying she won't struggle. I'm just saying she won't fizzle.

Let me explain the reasons I say that because normally given the situation, she probably would be toast...but here is why she's not:
1) She has a fairly large circulation. Large circulations can handle more shear than a smaller, compact system. It also means that even though she is entraining some dry air, since her circulation is so large she is able to pull in a lot of tropical air that can offset it.
2) Even though she has been sucking in dry air and getting sheared, her pressure is slowly falling. That means there are some baroclinic processes at work in deepening her. It doesn't mean she's not tropical...just that she is getting some help from a non-tropical process.
3) Her history shows that she is deepening, regardless of the shear or dry air. She won't go into a rapid deepening because of her environment, but she has "staying power."

When you add all of that up...it equates to her not being toast...even though there is an upper low to her west...shearing her and sending in some dry air.

One thing to remember is that each system is different. What would normally destroy one system might only weaken another. General rules are good to use...but you have to look for when a system is acting in exception to those rules...then you have to figure out why. Once you figure out "why"...then you can see if THAT reason is going to chance (like her large circulation)...and if it is not...then the general rules may not apply.

Hope that made sense.

[tailgater]

It makes lots of sense to me especially note 2. Thanks for taking the time to explain to the novice. Happy Hunting.