What factors could cause Ernesto to shift west??

[Noah]

He was headed way into the gulf a short time ago.

He is still tracking left/west now..or N/W, then he turns east.

What factors will keep him staying WNW?

Someone said NHC has not been calculating ridges to well.

This Ernie has really confused me and has me more interested in weather factors.

It really seems that only Mother Nature knows about theses weather systems.. Not our safistication.

[Wx_Warrior]

Not going into GOM and then head west...

[Sanibel]

Very simple. If the ridge nudges slightly west in reaction to a weaker shortwave approach from CONUS it could push the track back towards us.

This track is a little more solid, though, because the synoptic is fairly braced by the approaching shortwave from the west and the Bermuda High out in the Atlantic.


I would also be watching for the trend to continue more east as well.

[chrisnnavarre]

I think this would do it. The high pressure ridge (currently in S. Georgia) digging into Florida, being strong and not backing out eastward. Someone correct me if I'm wrong but wouldn't that do it? Could keep Big E. over the straits longer and then slam the Florida Keys as well.

[MiamiensisWx]

As the Bahamas ULL retrogrades west-southwestward, it may temporarily allow the mid-level Bermuda-Azores High ridging to temporarily build westward as the ULL weakens and drifts west-southwest. This has been indicated in the latest (11AM EST) discussion from the NHC, as shown below (highlighted in bold)...

SINCE THE CENTER IS CURRENTLY DIFFICULT TO LOCATE...THE INITIAL
MOTION IS A SOMEWHAT UNCERTAIN 325/9. A SMALL UPPER-LEVEL LOW TO
THE NORTH-NORTHWEST OF ERNESTO MAY BE IMPARTING SOME NORTHWARD
COMPONENT TO THE TROPICAL CYCLONE'S MOTION. DYNAMICAL MODELS
INDICATE THAT THE UPPER LOW WILL MOVE WESTWARD AND WEAKEN. THIS
SHOULD RESULT IN A LEFTWARD BEND OF THE TRACK IN THE NEAR TERM.
GLOBAL MODELS INDICATE THAT THE MID-TROPOSPHERIC HIGH PRESSURE
SYSTEM OVER THE SOUTHEASTERN UNITED STATES WILL SHIFT
EAST-SOUTHEASTWARD DURING THE NEXT COUPLE OF DAYS AS A TROUGH MOVES
IN FROM THE NORTHWEST. THIS WOULD RESULT IN A NORTHWARD TURN OF
ERNESTO. THE OFFICIAL FORECAST TRACK HAS BEEN NUDGED JUST SLIGHTLY
EASTWARD FROM THE PREVIOUS ONE...IN GOOD AGREEMENT WITH THE CURRENT
CONSENSUS OF THE DYNAMICAL TRACK MODELS.

There is the synoptic reasoning for a temporary north-northwest to northwest movement after exiting Cuba.

[bucman1]

Question is-Why would the track go east if the bend is to the west??

[TampaFl]

The high is clearly seen over S. Ga. on the WV Loop. At this time it appears to be stationary as it has been the last 24 - 36 hrs. What if this high moves more east than southeast and is stronger than forecast.? Would this senario allow Ernesto to move NW for a longer period of time before turning north? Thoughts & comments welcomed.


Robert

http://www.goes.noaa.gov/HURRLOOPS/huwvloop.html