Tropical Storm Gabrielle

[HAltschule]

Latest satellite loops from early Sunday afternnon show a nicely organized rotation off of the Savannah, GA coast. This area of low pressure is directly over the untapped, hot Gulf Stream waters. It bears close watching since it appears to be VERY close to TD status now. Many of the models develop this system and bring it on various tracks. 2 models bring it eastward and then stall it (courtesy of Bermuda High)...before tracking it westward again. One of these models bring the system inland over Florida while another shoots the system northward to the Cape Hatteras, NC coastine and possibly the Southern New England coastline as a Hurricane in a few days. The GFDL bring the system to TS status in 3 days and has it affecting NE Florida and SE GA with TS winds.

Regardles, I think we have a tropical system in the making and it should be interesting to watch. All eyes on the Eastern Seaboard for now.

 

[Gregg Gallina]

Yes... then you also have 98L that is out in the central Atlantic. Though devoid of convection now...it could have potential considering it has the closed LLC. It all depends on the upper level trof moving out/digging north of the VI (pot. increasing northerly shear).

 

[B Ozanne]

Seems like one of these will eventually develop.

Last week I was watching some persistant disturbances along the Atlantic Coast. While everyone was watching the Carolinas another low spunup just off Jersey. It got ripped apart by a front but there was an impressive circulation center.

 

[Gregg Gallina]

If you can find a MSG loop off west Africa...there is an incredible surge (strong outflow from collapsing MCS?) blowing across the Northern Cape Verde islands right now. This is the intense wave that has been forecasted to come off Africa by the global models for some runs now.

 

[HAltschule]

Seems like one of these will eventually develop.

Last week I was watching some persistant disturbances along the Atlantic Coast. While everyone was watching the Carolinas another low spunup just off Jersey. It got ripped apart by a front but there was an impressive circulation center.

I was watching this also. It had great circulation and a center but only fair weather cumulus or perhaps some TCU's at best within the system. It wasn't impressive at all.

The difference between the SE coast low now and the others from last week is that there seems to be a VERY good low level circulation already and some of the more reliable models are picking this thing up and hanging on to it. Ie...GFS, GFDL. Almost all of the others pick it up too but do not develop it as much. The more reliable models did nothing with last week's waves. Between the great circulation and convection already present and the reliable models forecasts, I am putting some heavier weight on this one actually forming into something.

 

[B Ozanne]

There were a few hours when the mass of convection was over the center of circulation then it got blown off to the northeast and left behind the fair weather cu circulation. I guess it wasn't that impressive but given the location it was interesting.

The Carolina system was looking a little ragged a few hours ago.

 

[Marc Austin]

The system looks farily healthy on vis satellite this afternoon. The low level circulation is fairly clear as the convection is somewhat removed from the center. Still, I've seen tropical depressions that look less impressive than this. It will be interesting to see what this thing ends up doing. It looks much healthier than either of the disturbances that were in the area last week. I'll keep my fingers crossed.

 

[B Ozanne]

It's now labeled as "invest" on the NHC satellite floaters.

 

[HAltschule]

It's now labeled as "invest" on the NHC satellite floaters.

Indeed. It is now being labeled at Invest 99L. Please also note that there are special GFDL and HWRF model runs on this invest. The GFDL develops it into a CAT 2 hurricane and keeps it erratically moving around in the Western Atlantic Ocean while the HWRF strengthens it into a CAT 1 hurricane and brings it on a course that threatens Eastern Long Island and Cape Cod.

I may have a Northeast US Hurricane chase yet?!?!

 

[HAltschule]

PS: The 12z Canadian model brings a monstrous Hurricane southeast of ACY in New Jersey in 144 hours. This model site does not go any further out than 144 hrs but it seems that the track would ALSO favor HWRF track and threaten NJ, NYC, Long Island, CT and MA with a significant hurricane.

PS 2: After drifting east, the GFS also reverts the system on a W to WNW track similiar to the other models but not as close to the East coast.

PS 3: The FSU MM5 is a major outlier and brings the system across central FL and inland over the SE as nothing more than a weak unorganized low.

 

[Matthew Crowther]

Virtually all models now suggest some sort of TS or hurricane (Gabrielle)
affecting the east coast from North Carolina to southern New England
beginning this weekend.

 

[HAltschule]

As of 2:00pm EDT Tuesday, BUOY 41012 (which is to the west of the center and out of the convective burst) is reporting a sustained wind of 15-20mph with gusts to around 25 mph. Latest Satellite loops show convection is begining to wrap around closer to the center of circulation which will allow it get more organized.

In other words, it looks like this system should be a TD very shortly.

PS: Seems as though most models bring an initial landfall over the Cape Hatteras, NC area as of now.

 

[cdcollura]

Good evening,

One thing that many are apparently overlooking is the INCREDIBLE amount of NW flow at high altitudes (try looping a visible, and see high clouds just racing NW to SE and menwhile the developing storm is drifting at the surface).

Shear kills tropical systems ... A TD or minimal storm will be the best you'll get out of this one (ofcourse, if the shear goes away, different story).

The weak LLC is already looking like an "exposed center" (all the convection E of the surface low).

 

[Stuart Robinson]

18z GDFL and GFS actually keep this storm out at sea, just missing the S.C. coast - however (as we all know) with the slight steering currents for the storm ANY storm track is possible right now - we need to see how the high to the North of the storm evolves and that wont be known for about 48 hours..

 

[Mitchell Daszewski]

Dynamic models have picked up on this system early on because it's basically a cutoff 500MB low that got left behind. As a ridge builds around and over it through time it's forecasted to strengthen, most likey as a tropical warm core system.

Many times these systems go off an become subtropical in nature, but I think based on models and upper level representation that this one will indeed be a pure tropical warm core system and swing around the developing ridge.

Historically these systems just barely miss or brush the east coast before accelerating north via the westerlies. I would imagine the same thing happens here...how close it gets to land is always the tricky part, but I would not expect more than a CAT 2, and with a large overall circulation.

These are always fun to watch.