• A Level 4 out of 4 flood risk has been issued for parts of Los Angeles beginning Christmas Eve, indicating a high potential for flash flooding and mudslides.
• The National Weather Service warns that areas including Downtown Los Angeles and the San Fernando Valley could receive a month's worth of rain in just days.
• Residents are urged to avoid flooded roads and prepare for rapidly changing conditions, as high-risk flood days account for a large share of flood-related deaths and damages.