GLENDORA (CBSLA.com) — Residents living in burn areas were on high alert Thursday as a powerful winter storm moves into the Southland.

Glendora city officials plan to distribute 20,000 sandbags Thursday to residents affected by the Colby Fire.

READ MORE: Rain Expected Sunday Night Into Monday In Southland

The city’s alert level was escalated from Yellow to Orange around 10:30 a.m. and voluntary evacuations were in place. Residents choosing not to evacuate are being asked to sign a Refusal to Evacuate form, acknowledging their awareness of the hazards/risk and assuming all liability for the decision to remain and shelter in place, KNX 1070’s Pete Demetriou reports.

An evacuation center was established at the Teen Center, 241 W. Dawson Avenue.

Glendora officials warned that when the rain begins overnight, the alert level could be raised to Red, meaning mandatory evacuations.

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Los Angeles County public works crews have been working to remove debris from catch-basins in the area in hopes of preventing flooding by giving rain runoff a clear path out of the area.

The National Weather Service warns the storm could dump up to 2 inches of rain on coastal and valley communities and up to 4 inches in the foothills and mountains.

A flash flood watch will be in effect from late Thursday through Friday evening in the San Gabriel Mountains and the San Gabriel and Antelope valleys. A flood watch will also be in effect in Orange County, particularly in the Silverado Canyon burn area on Friday and Friday night.

A high wind warning will be in effect starting Thursday night in parts of Los Angeles and Ventura counties and will expire at 7 a.m. Friday.

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