Hurricane Helene - Cat. 3

[cycloneye]

HenkL,anything from Namma about this system?

http://www.nhc.noaa.gov/tafb_latest/TSA_latestBW.gif

It has a low pressure.

Full Disk Image

[HenkL]

Here it is (forecast from NAMMA project):

"Forecast discussion for Sunday, September 10, 2006
September 10th, 2006

The current wave at approximately 27 W has started becoming more disorganized, so the flight plan today has been cancelled. No models are developing anything significant from the current system in the next few days, as the system is being torn apart by southerly shear. A retrograding upper-tropospheric trough at 27 N, 32 W is pulling air from the south above the current wave system; thus, this wave is being abandoned. The next wave shows distinct circulation and is currently located at 13 N, 5 W (near Bamako, Mali), but the models are disagreeing on its translational speed. The model consensus is that the wave will slow down and exit the coast sometime on Tuesday, September 12. The FSU MM5 has its exiting at 06Z, while the FSUSE, GFS, and UKMet have its exiting later in the day between 12Z and 18Z. This wave does appear to be the better choice, as low-level wind analysis indicates that the second wave has more moisture, a favorable location with respect to the African Monsoonal flow, and a dominant role in determining the zonal flow. The first wave is bypassed almost completely by the zonal flow just north of the ITCZ.
The next few forecast meetings will focus on monitoring and tracking this system as it progresses across the African continent."

The forecasts can be found here.
I was looking at this system already, because both the GFS and the ECMWF indicate a developing system SE of the Cape Verde Islands in a few days.

[cycloneye]

Thanks for the rapid reply. It looks like the next candidate for development if all the conditions are right.

[cheezyWXguy]

HenkL,anything from Namma about this system?

http://www.nhc.noaa.gov/tafb_latest/TSA_latestBW.gif

Ii has a low pressure.

Full Disk Image

That full disk image is incredable!! I thought they messed up the land areas and put africaa where Florence was! Very well organized storm

[JonathanBelles]

HenkL,anything from Namma about this system?

http://www.nhc.noaa.gov/tafb_latest/TSA_latestBW.gif

Ii has a low pressure.

Full Disk Image

That full disk image is incredable!! I thought they messed up the land areas and put africaa where Florence was! Very well organized storm

i need an authorization name and password to see the full disk

[HurricaneMaster_PR]

Looks impressive in this satellite shot....

[WindRunner]

Hehe . . . it's almost the size of Florence . . .

[cycloneye]

fact,registration is for free.

http://www.sat.dundee.ac.uk/registerql.html

[cycloneye]

Cloud tops haved warmed a little bit compared with 6 hours ago,but still looks good with that low around 12n.

[SouthFloridawx]

This is the wave that the models are showing to develop soon.

[benny]

Almost all models like this wave. It is pretty amazing how well in agreement they are. Although they are all in agreement over it being a distant fish storm too.. :/

[Zardoz]

Almost all models like this wave. It is pretty amazing how well in agreement they are. Although they are all in agreement over it being a distant fish storm too.. :/

Is that because it's above 10N? Would it need to come off the coast at around 8N or 9N for the models to indicate something other than fish?

[SouthFloridawx]

Almost all models like this wave. It is pretty amazing how well in agreement they are. Although they are all in agreement over it being a distant fish storm too.. :/

GFS has seemd to trend farther and farther west on each run with this wave. One thing I noticed about the runs was the Upper Level Low weakening the ridge. Is that possible. Either way later in the run fairly decent Mid-Leve trough comes down and scoops it out. However I would be wary since it's not at real I high latitude and the models weaken the ridge with and ULL. If the system gets past the eventual weakness it will keep going west.

[WindRunner]

Almost all models like this wave. It is pretty amazing how well in agreement they are. Although they are all in agreement over it being a distant fish storm too.. :/

GFS has seemd to trend farther and farther west on each run with this wave. One thing I noticed about the runs was the Upper Level Low weakening the ridge. Is that possible. Either way later in the run fairly decent Mid-Leve trough comes down and scoops it out. However I would be wary since it's not at real I high latitude and the models weaken the ridge with and ULL. If the system gets past the eventual weakness it will keep going west.

Yes, since the models do tend to show a slight lower-level reflection of the ULL down to at least the 850mb level, so it will probably create somewhat of a weakness in that area. Enough to cause a full recurve? I'd say only if it has developed full into a hurricane before reaching 30-35W, which some models are indicating. Otherwise, this could be a scenario similar to Florence in terms of the shape of the track as it once was forecasted - first WNW, shifting to NNW, then back to around W again for a while. Still a long ways out, but if the weakness doesn't completely pick it up, then that's what I'm seeing.

[Robjohn53]

Looks impressive wonder what it will really do...

[SouthFloridawx]

Almost all models like this wave. It is pretty amazing how well in agreement they are. Although they are all in agreement over it being a distant fish storm too.. :/

GFS has seemd to trend farther and farther west on each run with this wave. One thing I noticed about the runs was the Upper Level Low weakening the ridge. Is that possible. Either way later in the run fairly decent Mid-Leve trough comes down and scoops it out. However I would be wary since it's not at real I high latitude and the models weaken the ridge with and ULL. If the system gets past the eventual weakness it will keep going west.

Yes, since the models do tend to show a slight lower-level reflection of the ULL down to at least the 850mb level, so it will probably create somewhat of a weakness in that area. Enough to cause a full recurve? I'd say only if it has developed full into a hurricane before reaching 30-35W, which some models are indicating. Otherwise, this could be a scenario similar to Florence in terms of the shape of the track as it once was forecasted - first WNW, shifting to NNW, then back to around W again for a while. Still a long ways out, but if the weakness doesn't completely pick it up, then that's what I'm seeing.

This run was different than the runs yesterday as it takes it west but, stalls it out towards the end of the run.

Caution for dial up this is the 384 hour loop of gfs:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... loop.shtml

[Robjohn53]

Looks impressive in this satellite shot....

Looks Impressive and Florence looks like she split in to

[N2FSU]

Good sat shot of it here:
LINK

[Mac]

Geez. It's already twisting. This may be a nice one.

[curtadams]

These things almost always look way better inland than they do a day or two after they come off the coast. Although a lot of model seem to be developing this.