San Diego County will be under a red flag warning on Sunday beginning at 8 a.m., the National Weather Service said Friday.
Originally, the NWS had the county under a fire weather watch but that was elevated Friday afternoon because of the gusty offshore winds and low humidity expected to arrive Sunday morning.
The warning means critical fire weather conditions are either occurring or will shortly.
Any fires that develop will likely spread rapidly and be difficult to contain. Outdoor burning should be avoided.
The most recent fire weather warning for San Diego County expired Friday morning.
On Thursday, Dec. 7, when the region faced critical fire risk, the Lilac Fire broke out in the North County.
The fire destroyed more than 100 homes and burned 4,100 acres.
High fire risk is expected to last into January, adding to fears that months of deadly and destructive wildfire danger will extend into early next year.
In Ventura and Santa Barbara counties, the nearly 250,000-acre Thomas Fire has burned since Dec. 4.
Los Angeles County was under red flag warnings for 12 straight days until Friday, but the risk of wildfire is not yet over.
The warnings were first issued early last week because of gusty Santa Ana winds combined with very low humidity levels, then extended every day.