Weather Patterns:  Zonal Flow Versus Meridional Flow
Characteristic	Zonal Flow	Meridional Flow
Temperature	Seasonable	Unseasonably cold in troughs, unseasonably warm under ridges.
Precipitation	Wet near to somewhat north of jet. Dry elsewhere.	Wet near to somewhat east of trough axes, dry elsewhere.
Storms	Frequent, but weak to moderately strong near jet.  Infrequent   elsewhere.	Strong east of trough axes, weak elsewhere along jet, none away  from jet.
Comments	Changes at a location may occur as jet shifts northward or southward.	If pattern is progressive, i.e., the troughs and ridges keep shifting,  storms and fair weather regimes are well distributed. If pattern is  nearly stationary or recurrent, droughts and floods may occur