Zonal flow is a meteorological term meaning that the general flow pattern is west to east, or east to west, along the Earth's latitude lines (as opposed to meridional flow). Extratropical cyclones in this environment tend to be weaker, moving faster and producing relatively little impact on local weather.
Famous quotes containing the word flow:
“On the idle hill of summer,
Sleepy with the flow of streams,”
—A.E. (Alfred Edward)