Petaluma Readies For Next Round Of Atmospheric River

PETALUMA, CA — The Petaluma Police Department on Tuesday issued a weather advisory for the next round of atmospheric river events expected to begin early Wednesday morning in the North Bay and the Bay Area.

Sonoma County remained under a flood watch expected to take effect at 4 a.m. Wednesday and continue through 4 p.m. Thursday, according to the National Weather Service. A high wind warning also takes effect at 4 a.m. Wednesday and continues through 10 a.m. Thursday, the weather service said.

In Petaluma because the ground is already saturated from last week’s rain, the storm may cause flash flooding and downed trees; power outages are likely through early Friday morning; and rapid ponding of water in urban and poor drainage areas is possible. 

Public Works, Fire and Police personnel were preparing to respond to road closures, blocked storm drains and storm-related debris falling on the streets and sidewalks if needed, police said.

Police urged Petaluma residents to ensure the safety of themselves and the community by doing the following:

• Clear Gutters and Storm Drains - Keep drainage areas and pipes around your property clear of debris that could cause flooding.
• Check on Your Neighbors, Friends, and Family - Especially those who may be vulnerable in case of emergency.
• Get Supplies - Make sure you have drinking water, flashlights, and other essentials on hand before the rain begins Wednesday morning.
• Turn Off Power and Gas - If your property is in imminent danger of flooding, please call PG&E at 1-800-743-5000 to request that your power and natural gas be shut off, or for guidance on how to do it yourself.
• Use Sandbags - Sandbags can help protect areas where water could enter your living space. Get free sandbag supplies from the City of Petaluma at the following locations before and during heavy rain events: Far north end of Hopper Street, 24/7; and Prince Park - Sandbags will be available at the entrance to Prince Park located to the right in the empty parking lot. Please note that there will be no signage in the area until Wednesday, but the station is open 24/7 regardless of signage.

• Move Valuables - Move furniture, important paperwork, and valuables to higher areas of your dwelling to minimize damage.

Driving In The Rain

Petalumans were urged to avoid unnecessary travel; stay clear of and do not approach downed power lines (Use 911 to report downed power lines); Use caution when traveling on the roadways, as most flooding deaths during a storm occur in a vehicle.

Petalumans should not try to drive through flooded areas. If street lights are out, treat the intersection as a 4-way stop.

The police department advised all drivers that speed limits should be reduced during inclement weather. Drive slowly if you see public safety personnel performing traffic control or clearing storm debris. 

Further, Petaluma police said drivers should not tailgate in the rain; should pay attention to signs indicating road closures or flooded areas; and should turn on their headlights if their windshield wipers are turned on.

Atmospheric River May Result In Loss Of Human Life, Forecasters Say

The entire Bay Area will be under a flood watch beginning Wednesday morning due to a heavy storm system expected to be as bad or worse than Saturday's deluge and which will likely result in the loss of human life, according to a dire forecast update from the National Weather Service.

The update issued Monday afternoon included five key points, with the first one noting a "threat to life likely during this storm." Mudslides are anticipated due to saturated soil, and rapidly rising creeks and streams will pose additional dangers.

A meteorologist shared the following observations in the forecast about the coming storm: "To put it simply, this will likely be one of the most impactful systems on a widespread scale that this meteorologist has seen in a long while. The impacts will include widespread flooding, roads washing out, hillside collapsing, trees down (potentially full groves), widespread power outages, immediate disruption to commerce, and worst of all, likely loss of human life. This is truly a brutal system that we are looking at and needs to be taken seriously."

The forecast includes an updated threat matrix it classifies as "extreme risk" for conditions expected Wednesday and Thursday, including increased wind gusts, a flood watch that now includes the entire Bay Area and an added forecast Friday through Sunday after the big storm for roughly 1-2 inches of rain in most areas.

Wednesday through Thursday morning will be the worst of the storm, with heavy rain and strong winds with gusts of 35-55 mph in most areas, with stronger gusts at higher elevations.

The flood watch will be in effect from Wednesday morning through Thursday afternoon, with rain amounts expected from 2-4 inches in the valleys, 3-6 inches in the foothills and 8-10 inches in the coastal mountains.

Tuesday was expected to have little to no rain for the region and represents the last opportunity to clean up from Saturday's storm before the next one hits, forecasters said.

For the latest forecast updates, visit Weather.gov/bayarea and AccuWeather.

Here's What The National Weather Service Says You Need To Know

• Make sure you're signed up for your county's emergency alerts and/or reverse 9-1-1 calls (City of Petaluma -- cityofpetaluma.org/sign-up-for-emergency-alerts; Sonoma County --https://socoemergency.org/get-ready/sign-up/socoalert/).
• Heed any evacuation orders, especially if you live near an area that is prone to flooding or mudslides
• Have a "go bag" ready in case you need to evacuate quickly (go to ready.gov/plan or ready.gov/kit if you're not sure what to pack).
• Find your insurance policies and other important documents. Take photos of rooms in your home so that you can easily reference items in case of damage.
• Prepare for power outages or road closures that could last several days. Get extra non-perishable food and have drinking water ready at home in case you`re unable to leave home.
• Gas up your vehicles and charge up all your devices.
• Plan ahead for the elderly or others with special needs, such as necessary medications or other services.
• Don't forget about your pets/livestock to ensure their safety.
• Remember that impacts can be ongoing even after the heaviest rain is over. Mudslides can sometimes occur several days or even weeks after heavy rain events. Flooded waterways may take days to recede.

The National Weather Service said this wet pattern will continue to bring waves of moderate rain into the second week of January which means soils could stay saturated for quite some time, allowing slides, downed trees and other impacts to persist.

Bay City News Service contributed to this report.