But no one had anticipated the low pressure system, he said.

On October 3, it became a type of low pressure system.

Later that day, Bob was absorbed by a low pressure system.

The low pressure system began to strengthen, and slowly moved east.

A very low pressure system that moved from the West cooked up strong winds.

Later that day, it turned into a frontal low pressure system.

A weak low pressure system and associated cold front will pass north of the region Thursday night.

Another low pressure system will approach later next week.

The low pressure system maintained a cold core and had not yet established itself at the surface.

A very strong low pressure system was approaching the northwest coast of California.