It could take weeks or months for the public to know what caused the fire that last month charred 6,600 acres in the Otay Mountain Wilderness as local Cal Fire officials continue their investigation.

A new wildfire was reported today at 1:58 p.m. in San Diego County. The wildfire has been burning on private land. At this time, the containment status is unknown and the cause of the fire remains undetermined.

According to the National Weather Service, a flood watch is in effect for San Diego County from Thursday afternoon through late Thursday night.

The storm is expected to bring about 2 inches of rain to northern and southern parts of the county between Wednesday and Friday

Border 2 Fire initially started 1:58 p.m. Jan. 23 in San Diego County. After being active for six days, it has burned 6,625 acres. A fire crew of 1,510 effectively contained 90% of the fire by Wednesday morning. The blaze's cause remains under investigation.

There is up to a 15% chance of light precipitation on Tuesday as the marine layer deepens from coastal to foothill areas throughout the county, with the heavier rain arriving later in the week, forecasters said.

Wet weather is on its way to San Diego County Monday, with rain arriving as early as Tuesday, forecasters said