New Ivan Forecast... 135KT for the islands

[Stephanie]

Thanks Derek for the update!

[lilbump3000]

Derek i think you need to up the winds for the islands. Possible Cat. 5 going threw there.

[Derek Ortt]

which models show a recurvature? Not one that I have seen shows a recurvature.

[dennis1x1]

gfs...others have been shifting north with every run also...

http://www.wunderground.com/tropical/tr ... model.html

[huricanwatcher]

looks like an NC storm for sure

[dennis1x1]

decent chance if the trough scenario plays out.....too early to tell.

[B-Bear]

GFS has been discounted.

[dennis1x1]

discounted? by who? it just ran

[Derek Ortt]

looks at the AVNI model run. The AVNO (operational GFS control) does not even do a vortex relocation. Besides, I have more confidence in my ex than I do in the GFS model

[bahamaswx]

Better off only looking at the GFS through 86hours.

[dennis1x1]

all the models (bam excluded) bring it to a point where recurvature would be a good possibility climatology speaking.

[Stephanie]

Yeah, GFS is only good at short-tem forecasts. However, it does have the tendency of picking up on something far out but then it drops it in the medium range.

[B-Bear]

Today's 12Z model runs are in very good agreement on a track throughout the 5 day period...with one exception. The 12Z NOGAPS...the 12Z European...12Z UKMET and most recently the 18Z GFDL...all present the same general scenario. Ivan will begin bending more to the WNW tomorrow and travel around the periphery of the Atlantic ridge. Late in the forecast period...Ivan should move more to the northwest as the western extent of the Atlantic ridge weakens some. This is the reason for the track close to the Dominican Republic and into the southern Bahamas. The official forecast from the NHC closely follows this track and is in good agreement with the model consensus. The only outlier...once again...is the 12Z GFS which appears to be too weak with the initialization of Ivan...and hence takes it too far to the west in a weaker steering layer.

NHC said something similar. I have seen nothing suggesting they are giving the latest run any more credence.

[Derek Ortt]

GFS doesn't show Ivan moving north. It has an open wave moving north

[NorthGaWeather]

all the models (bam excluded) bring it to a point where recurvature would be a good possibility climatology speaking.

Hmmm are you looking at the current models? I guess a WNW motion thru the Bahamas is showing recurvature. Looks like the models show a Bahamas hit moving NW towards Florida.