Bay Area Braces for Heavy Rain and Flood Watch

The San Francisco Bay Area is gearing up for a significant atmospheric river event, bringing heavy rainfall and concerns about potential flooding through Christmas Day. A Flood Watch is currently in effect for parts of the North Bay, but residents across the region, including San Jose, should prepare for widespread impacts and challenging weather conditions.

Heavy Rain and Flood Watch Alert

The National Weather Service has issued a Flood Watch, specifically highlighting the North Bay, as a robust atmospheric river pattern settles over the region. This system is expected to deliver multiple rounds of moderate to heavy rain, especially from Thursday evening through Saturday morning, though intermittent showers will persist into Monday.

While the Flood Watch is concentrated on the North Bay, particularly areas prone to flash flooding and debris flows, the entire Bay Area is forecast to experience substantial rainfall. Locals in San Jose and the wider South Bay should remain alert to urban flooding risks, saturated ground conditions, and potential travel disruptions.

Projected Rainfall Totals

Forecasts indicate varying rainfall amounts across the Bay Area, with the North Bay mountains expected to receive the brunt of the precipitation. However, even lower elevations will see significant totals that could lead to localized issues. The heaviest rain is anticipated Thursday night into Friday morning, and again Friday night into Saturday morning.

These totals are cumulative over the multi-day event, with the higher elevations having the potential for localized amounts exceeding 12 inches. Even relatively lower amounts in urbanized areas like San Jose can quickly overwhelm storm drains, leading to street flooding and hazardous driving conditions.

Potential Impacts and Hazards

The prolonged period of heavy rain brings several potential hazards that Bay Area residents should be aware of:

• Flooding: Urban and small stream flooding is highly likely across the region. Underpasses, poor drainage areas, and street intersections can become impassable. For the North Bay, rapid creek rises and potential overflow are significant concerns, especially near burn scar areas from previous wildfires where debris flows are a greater risk.
• Landslides and Mudslides: Saturated hillsides, particularly in the North Bay and along coastal areas, will be susceptible to landslides and mudslides. Even smaller slides can block roads and threaten infrastructure.
• Travel Disruptions: Road closures due to flooding, fallen trees, or landslides are possible. Drivers should anticipate significant delays, reduced visibility, and hydroplaning risks. Public transportation may also experience impacts.
• Power Outages: High winds associated with some of these systems, coupled with saturated ground, increase the risk of trees falling onto power lines, leading to localized power outages.
• Coastal Concerns: While the primary focus is rain, coastal areas may also experience elevated surf and minor coastal flooding during high tides, exacerbating runoff issues.

Staying Safe During the Storm

Preparation is key to navigating this multi-day weather event safely. Here are practical tips for San Jose and Bay Area locals:

• Monitor Alerts: Stay informed by monitoring local news, weather forecasts, and official alerts from the National Weather Service.
• Clear Drains: Ensure storm drains near your home are clear of leaves and debris to prevent localized flooding.
• Emergency Kit: Have an emergency kit ready with essentials like flashlights, batteries, bottled water, non-perishable food, and a charged phone.
• Secure Outdoor Items: Bring in or secure any outdoor furniture, decorations, or other items that could be blown away or washed away.
• Driving Safety: If you must drive, do so with extreme caution. Reduce speed, increase following distance, and turn on headlights. Never drive through flooded roads – “Turn Around, Don’t Drown.” Just six inches of moving water can sweep a car away.
• Avoid Flood-Prone Areas: Stay away from creeks, rivers, and areas known to flood.
• Power Outage Preparedness: Charge electronic devices and have alternative light sources ready. If you experience an outage, report it to your utility provider.

Frequently Asked Questions

• Is the entire Bay Area under a Flood Watch?
  The primary Flood Watch currently targets portions of the North Bay, including Marin, Sonoma, and Napa counties. However, the heavy rainfall means urban and localized flooding is possible across the entire Bay Area, including San Jose, so vigilance is advised everywhere.
• How long will this rainy weather last?
  Heavy rainfall is expected to be most intense from Thursday evening through Saturday morning, with showers continuing intermittently through Christmas Day, Monday.
• What should I do if I live in a flood-prone area?
  Clear storm drains, have sandbags ready if advised by local authorities, monitor water levels, and be prepared to evacuate if instructed by emergency services.
• Will there be strong winds with the rain?
  While the primary concern is heavy rain and flooding, some periods may include gusty winds, especially in higher elevations and along the coast, which could contribute to downed trees and power outages.
• How can I get real-time updates?
  Follow local news channels, radio, and official social media accounts from the National Weather Service and your county’s emergency services. Consider signing up for local alert systems.

As the Bay Area navigates this significant weather event, prioritizing safety and staying informed are your best defenses against potential hazards. Be prepared, be cautious, and have a safe holiday season.

Bay Area Braces for Heavy Rain and Flood Watch