Heavy precipitation and high snow levels are expected to slam California this weekend with potential for significant flooding. Forecasts from the National Weather Service (NWS) indicate moderate precipitation is projected to arrive Saturday, but the brunt of the storm should hit Sunday.
Travel will be significantly impacted. Other concerns include debris flows in burn-scarred areas due to recent wildfires.
Additional storms are possible beginning Tuesday and into next weekend. This weekend’s storms may only be the start of a prolonged event lasting into next week and possibly longer.
“How these storms evolve, their intensity, duration, and time between storms will determine whether this event is merely memorable or more historic in nature,” said NWS meteorologist Dan Keeton.
Dry conditions through Friday offer an ideal opportunity to prepare ahead of the impending storms. To that, Cal OES reached out to several NWS experts for preparedness tips, advisories and advice on this weekend’s storms.
The following panel of NWS experts issued information based on their specific regions:
- Chris Smallcomb (Northeast California and eastern side of the northern Sierra)
- Ryan Aylward (Northwest California)
- Dan Keeton (Sacramento Valley and northern Sierra)
- Eric Boldt (Los Angeles and south-central coast)
- Brian Garcia (San Francisco Bay Area and central coast)
Smallcomb: “Make good use of the break in the weather on Friday. That is your best time to prepare for flooding coming later this weekend.”
- Clear snow away from street drains and keep piles of snow away from drainage areas that can cause water backup and increase flooding.
- Clear out gutters of leaves and snow. Even if you don’t live in a flood prone area, flooding can impact your home from clogged gutters and street drains.
- Be extra mindful of flooding potential around new construction areas.
- If traveling over the Sierra, most of the storm will see torrential rains. This will delay travel much like a snow storm due to ponding water, low visibility, rock slides, and hydroplaning. Plan to allow plenty of extra time for driving.
Aylward: “It should also be noted that this storm system over the weekend is only the first in a series of systems to impact Northwest California. The National Weather Service is closely monitoring the potential for a stronger storm to move through Northwestern California Tuesday into Wednesday bringing strong winds, minor coastal flooding, and even heavier rainfall.”
- Potential for small stream and creek flooding and also rock or mud slides in steep terrain.
- Recommend people planning on traveling this weekend to closely monitor road conditions with Caltrans at http://quickmap.dot.ca.gov/ especially if heading south toward the San Francisco Bay Area where the rain is forecast to be heaviest.
Keeton: “This is going to be a prolonged event lasting through next week, maybe even longer. This may be some of the most significant flooding we’ve seen in inland NorCal in over a decade.”
- Learn if you live in an area with any history of flooding – you may be in a flood prone area and not know it because it hasn’t flooded for many years.
- Prepare in case you have to leave suddenly. Make a plan for you and your friends and relatives who may need assistance should an evacuation become necessary. Know where to go and how to get there.
- Gather important papers (insurance medical records, birth records, etc), mementos, and things you can’t do without (like medications) so you’ll be able to quickly take them to safety.
- Have a plan for pets.
- If you are asked to evacuate, do so.
- Keep yourself informed of the current situation…forecasts change as storms evolve.
Boldt: “The storm system expected late Sunday and Monday will not have as much impact across southwest California compared to central sections of the state, however normal preparedness actions should be taken to deal with any drainage problems, power outages, and potential travel delays due to the storm.”
- Ponding of water on roadways can create hydroplaning and unsafe travel conditions. Slow down and allow more distance between cars if you have to travel during the storm. Never drive through standing or moving water.
- Snow levels will be very high and not a factor for travelers in southwest California during this event.
- Low-lying drainage areas and small streams may experience minor flooding during heavier rain late Sunday through Monday morning.
- Minor mud and debris flows will be possible near recent burn scars during heavier rains, especially the Sand Fire near Santa Clarita, and the Fish Fire near Duarte. Listen to local officials for preparedness actions and any evacuations if you live near a burn area.
- The combination of surf, winds, and astronomically high tides on Sunday and Monday could create local beach erosion and minor coastal flooding for area beaches.
- Trees stressed by the drought in combination with saturated soils can lead to tree failure, property damage, and possible power outages.
- Additional rain is expected next week (possibly Wednesday and Friday) which will continue to saturate soils and loosen debris from hillsides.
Garcia: “Make your travel plans around the weather. If you can change your travel and/or outdoor plans, this would be a good weekend to do so.”
- Do not drive or walk across flooded areas.
- Have extra food and water on hand.
- Have flashlights and extra batteries on hand in event of power outages.
- Know your risks, prepare now.
- Listen to officials for evacuation orders.
- Follow the National Weather Service online, on social media, and through NOAA Weather Radio for the latest information.
For additional county weather-related information, contact your respective county office here.