Blue Line Trolley commuters were delayed Wednesday because of a tree that fell near the E Street Station in Chula Vista.
The downed tree led to service disruption around 6 a.m. Wednesday, according to the San Diego Metropolitan Transit System.
The Blue Line runs between the UTC Transit Center in La Jolla through downtown San Diego to the Mexican border, including National City and San Ysidro.
Transit crews were working to resolve delays as soon as possible, MTS officials said.
It was unclear what caused the downed tree, but strong gusts in the area might have been the culprit.
No injuries were reported.