The National Weather Service has issued urgent flood advisories for the Bay Area as a powerful storm system continues to batter Northern California. Major road closures are already reported across San Francisco, with officials warning the worst flooding may yet come during high tides tonight.

Forecasters predict this multi-day rainfall event could drop up to 5 inches in some areas, potentially surpassing last year’s storm totals. Emergency crews are scrambling to clear flooded highways as thousands of commuters face difficult travel conditions.

National Weather Service Warns of Bay Area Flooding: Duration Forecast and Road Closure Updates

Extended Rainfall Forecast for the Bay Area

The National Weather Service has issued flood advisories across the Bay Area as a potent storm system continues to unleash heavy rainfall. Meteorologists predict this atmospheric river event will bring sustained precipitation through Sunday evening, with rainfall totals reaching 2-5 inches across the region. The most intense downpours are expected overnight Wednesday into Thursday morning.

Urban areas may see 2-3 inches accumulation, while higher elevations like the Santa Cruz Mountains could receive up to 5 inches. This prolonged wet pattern results from a stalled low-pressure system drawing moisture from the tropical Pacific. Residents should prepare for:

• Localized street flooding during high tide cycles
• Possible power outages in wind-prone areas
• Delays on public transportation systems

This storm reminds me of the 2017 atmospheric rivers that caused the Oroville Dam crisis. The ground is already saturated from January rains, so new rainfall will have nowhere to go except pooling on surfaces.

Current Road Closures and Transportation Impacts

Multiple major highways have experienced flooding, with significant impacts on Bay Area commuters. Caltrans reports the following critical closures as of Wednesday afternoon:

BART and Muni are operating with delays of 15-30 minutes systemwide. Ferry services between Oakland and San Francisco have added six extra crossings per day to accommodate displaced commuters.

I’ve observed water levels rising faster than normal around highway underpasses. The city’s aging drainage systems simply can’t handle this volume of water in such a short timeframe.

High-Risk Flood Zones to Avoid

The National Weather Service has identified several neighborhoods at particular risk of flooding during this event:

Coastal Flood Zones

Areas along the San Francisco Bay shoreline, including:

• Mission Creek in San Francisco
• Alviso in San Jose
• Point Richmond

Inland Flood Prone Areas

• San Anselmo Creek corridor
• Niles Canyon Road in Fremont
• Petaluma River watershed

Emergency management officials recommend that residents in these areas:

• Move vehicles to higher ground
• Prepare sandbags if available
• Monitor creek levels through local alerts

Many first-time homeowners in these floodplains don’t realize they’re at risk until it’s too late. The ‘100-year flood’ designation can be misleading – we’ve had three such events in the past decade alone.

Historical Context of Bay Area Flooding

While not as severe as historic events like the New Year’s Day flood of 1997, this storm ranks among the top 5 wettest periods of the past decade. Comparing key metrics:

What makes this event particularly concerning is its coincidence with astronomical high tides, creating compound flooding effects not seen since the 1990s.

The tide tables don’t lie – we’re experiencing lunar perigean tides that raise normal high tides by nearly a foot. When combined with storm surge and freshwater runoff, it creates a perfect flood scenario.

Emergency Preparedness Recommendations

The National Weather Service and local emergency services are urging residents to take these precautionary measures:

Before the Storm

• Clear leaves and debris from storm drains
• Test sump pumps if available
• Locate emergency shelters in your area

During Flooding

• Never drive through flooded roadways
• Monitor emergency alert systems
• Prepare for possible power outages

Of particular concern are elderly residents and those with mobility challenges in basement apartments, who may need assistance relocating to higher ground.

I’ve seen too many cars stranded in what drivers thought was ‘just a puddle.’ Remember – six inches of moving water can knock over an adult, and 12 inches can carry away most vehicles.

Long-Term Climate Considerations

This storm fits into a concerning pattern of more frequent and intense precipitation events linked to climate change. Key observations:

• Atmospheric river events have increased 15% in frequency since 1980
• The rainy season now starts later but delivers more intense bursts
• Sea level rise exacerbates coastal flooding during storms

Climate models suggest the Bay Area should prepare for:

• More volatile swings between drought and flood
• Higher rainfall intensity when storms do occur
• Greater need for updated flood infrastructure

While reservoirs need this rainfall, the delivery method creates problems. We’re getting our year’s water supply in destructive bursts rather than gentle, replenishing rains. Adaptation will require rethinking everything from zoning laws to drainage design.