Please explain why: Stronger = north track and Weaker = west

[Pileus]

nm

[dwg71]

It has to do with steering currents and the fact that stronger storms are pulled northward quicker. A weaker system can skate under the radar.

[cycloneye]

nm

More stronger a system it is driven by upper flow more north while a weak system is driven by the low level flow that moves westward.

[Pileus]

Another words, a stronger storm reaches higher aloft where it becomes
more influenced ?

[deltadog03]

it depends on how strong the system is...ie, a strong system has very high cloud tops (tstorms). usually in the range of 40-50k feet. Those will become influence by the winds aloft. example. if TD9/irene were stronger and say at strong TS then she would almost def.. be on the way out to sea. BUT, since it is weak and the Tstorms are not very high near the center than it will be influenced or steered by the Low Level Winds. I hope this helps

[Pileus]

Interesting tho how the ridge is not influential at low levels thanks dog.

[Derecho]

It's more a question of how influential the average trough is at lower levels; some troughs really don't exist at lower levels at all, thus a weak sheared storm basically ignores them, and even a deep-layer trough will typically have more influence further south at upper levels.

Thus a weak sheared storm will just scoot by east-west with the low level flow, which is generally east to west in the tropics.