Lines MET

"Iso" means "same" and all of these lines join different areas where a quantity is the same. "Bar" means pressure, so "isobar" is equal pressure. "Tach" means speed, so isotach is equal speed, here meaning wind speed. Finally, isohypses join areas of equal height (for a given pressure.) These look and feel and behave in exactly the same way as isobars on surface pressure charts, so you can use Buy Ballot's law in exactly the same way.