ATL: IGOR - Ex Hurricane - Discussion

[Dean4Storms]

I think the 12z NOGAPS showed this SW jog today, but I believe it didn't start until it reached close to 40w. Maybe the model is correct in foreseeing the turn SW but just a bit later than it actually has occurred. If that is the case the other global model runs will be interesting tomorrow for sure. Could be that the sub-tropical ridge is much stronger than the other models latched onto!

[cycloneye]

SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...17.1N 34.9W
ABOUT 725 MI...1170 KM W OF THE CAPE VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/HR
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 21 MPH...33 KM/HR
MINIMUM CENTRAL PRESSURE...1000 MB...29.53 INCHES

[Florida1118]

According to the NHC its moving WNW...

[blazess556]

...BUT
SEVERAL EARLIER MICROWAVE OVERPASSES INDICATED THE POSSIBILITY OF
THE LOW-LEVEL CENTER LYING UNDERNEATH THE CONVECTION. AN EXPANDING
UPPER-LEVEL OUTFLOW IS WELL ESTABLISHED IN ALL QUADRANTS EXCEPT TO
THE EAST. DVORAK INTENSITY ESTIMATES ARE AT 3.0/45 KT AND 3.5/55
KT FROM SAB AND TAFB...AND THE LATEST 3-HOURLY AVERAGED ADT VALUE
IS 3.3. GIVEN THE UNCERTAINTY WITH REGARD TO THE LOCATION OF THE
CENTER...THE ADVISORY INTENSITY IS INCREASED CONSERVATIVELY TO 45
KT.

[gatorcane]

According to the NHC its moving WNW...

Right but that is just a long-term average. If you read the discussion there is much doubt on the short-term movement and there could be a center relocation farther sw.

[hurricaneCW]

I think the LLC is eventually going to drag wsw towards the convective ball as the shear continues to decrease and the convective ball keeps heading wsw.

[SouthFLTropics]

According to the NHC its moving WNW...

Right but that is just a long-term average. If you read the discussion there is much doubt on the short-term movement and there could be a center relocation farther sw.

If it indeed does that I would think that it could have an important affect on the track further down the line, in particular for our friends in the islands.

SFT

[HURAKAN]

Latest

[sunnyday]

What is the possible "significant shift" mentioned for tomorrow?

[Aric Dunn]

IM pretty sure when the next microwave pass come they are going to find the center south of the 11pm position.

[AJC3]

IM pretty sure when the next microwave pass come they are going to find the center south of the 11pm position.

A boatload of usable ones coming up...(the last column is miles from NADIR)

2010/09/11 04:22:51 UTC AQUA 456
2010/09/11 04:23:20 UTC N-18 203
2010/09/11 04:23:40 UTC TRMM 463
2010/09/11 04:23:58 UTC CLOUDSAT 255
2010/09/11 04:32:33 UTC N-19 625
2010/09/11 06:42:13 UTC N-15 759

[Blown Away]

What is the possible "significant shift" mentioned for tomorrow?

Where did you see that, it's not in the 11pm discussion?

[Tropics Guy]

Short term average Igor appears to be headed WSW, will be interesting how the models will adjust to this, maybe a closer pass to the islands before recurving?

http://www.ssd.noaa.gov/goes/flt/t1/loop-avn.html

TG

[Fego]

A what time is that?

[SouthFLTropics]

I know IR is not a good way to track present movement but right now Igor looks to be sinking towards the ITCZ like a rock...If that isn't a WSW to SW movement I'll be stunned...

SFT

[Blown Away]

I know IR is not a good way to track present movement but right now Igor looks to be sinking towards the ITCZ like a rock...If that isn't a WSW to SW movement I'll be stunned...

SFT

Either there is some WSW movement or the system is being sheared leaving the LLC along the extreme NE side of the convection. I'm going w/ WSW movement given the symmetry of the circulation????

[Aric Dunn]

IM pretty sure when the next microwave pass come they are going to find the center south of the 11pm position.

A boatload of usable ones coming up...(the last column is miles from NADIR)

2010/09/11 04:22:51 UTC AQUA 456
2010/09/11 04:23:20 UTC N-18 203
2010/09/11 04:23:40 UTC TRMM 463
2010/09/11 04:23:58 UTC CLOUDSAT 255
2010/09/11 04:32:33 UTC N-19 625
2010/09/11 06:42:13 UTC N-15 759

Sounds like great fun then ... lol

Im pretty sure my extrapolation is a decent estimate. using the basis of a logarithmic spiral and the relatively calculable spiral bands arch angle its not too hard to extrapolate to the center. of course there is error as a tropical cyclone spiral band does not perfectly fit to logarithmic spiral .. but its very close.... I guess we are waiting till tomorrow to see what happens..

[Ivanhater]

[cycloneye]

Wow,great loop that shows the dip.

[SouthFLTropics]

That is a great loop Michael and I think it also appears that the center is on the north side of the convection...so with that in mind maybe the dip isn't as dramatic as the NHC IR is indicating...Time will tell

SFT