Predicting exactly where unusual or severe weather will occur this winter is impossible, but generally, the jet stream across the United States shifts storm tracks to the southern tier of states during an El Niño winter.
Key Messages from the NOAA Climate Prediction Center
Issued November 2, 2026 and Updated November 3, 2026
Atmospheric River Expected to Affect the West Coast StatesAtmospheric river activity is expected to pull significant amounts of moisture into much of the West Coast during the second week of November and weekend, with a potential secondary moisture surge later in the period. Strong surface low pressure just north of the region will also likely drive high winds along the immediate coastline.
(a) A moderate risk (40 to 60%) of heavy precipitation and possible flooding is indicated for Nov 11 to 15 across parts of the Pacific Northwest and northern/central California, while a slight risk (20 to 40%) extends to Nov 17 across the West Coast into the Desert Southwest, Great Basin, and Southern Rockies. High winds are possible across much of the West, including a moderate risk along the immediate West Coast Nov 11 to 15 and a broader slight risk extending to Nov 17.
(b) A moderate risk of heavy snow is indicated across the higher elevations of the Klamath and Sierra Nevada Nov 11 to 15. Slight risks of heavy snow extend to Nov 17 for high elevations of the Cascades, Klamath, and Sierra Nevada, as well as the Northern Intermountain, Great Basin, and Central and Northern Rockies.
Monitor local forecasts for safety alerts, avoid driving through flooded roadways, and use caution if traveling through high elevations. Be prepared for power outages due to high winds.
This is likely just the first of many such storms expected to impact the west coast this winter, and inland freshwater flooding is a major concern. Six weeks ago, in anticipation of these events, California Declared a State of Emergency to Bolster Statewide El Niño Preparedness.
The LA County website is urging both community and individual preparedness for what is expected to be a difficult winter, and advises:LA County is preparing its flood control and emergency response systems now. Crews are inspecting and maintaining dams, debris basins, channels, storm drains, and pump stations; monitoring burn areas, hillsides, and other areas at risk of flooding and debris flows; and preparing for evacuations, emergency shelter, and other storm response. County teams are also preparing to assist people experiencing homelessness, older adults, and others who may need additional help during severe weather.
Here’s what residents can do now:
- Sign up for emergency alerts: Go to alert.lacounty.gov to receive emergency notifications, including evacuation warnings and orders.
- Know the risks where you live: If you are near a hillside, canyon, recent burn area, or area that can flood, learn your flood and mudflow risk before a storm.
- Make an evacuation plan: Know where you will go and how you will get there if you need to leave quickly.
- Have supplies ready: Keep enough food, water, medications, and other essentials for up to 10 days.
- Prepare your home: Clear gutters, downspouts, and storm drains, fix roof leaks, and get sandbags before heavy rain is in the forecast.
- Consider flood insurance: Standard homeowners insurance does not cover flood damage. Flood insurance is separate and can take at least 30 days to go into effect.
- Need help with mud or debris flow risk? Call LA County Public Works at 1-800-933-0930 to speak with an engineer.
- Know someone experiencing homelessness who needs help? Visit homeless.lacounty.gov/get-help/
While this first round is expected to impact further north, now is the time for everyone along the west coast - and much of the southern United States - to prepare for severe storms and elevated flood risks.
Those interested in diving into one of the more extreme (albeit, based on historic events) scenarios of Atmospheric river flooding may wish to revisit 2022's California's ARkStorm Scenario Revisited & National Preparedness Month, but even a far less severe event could be devastating.
Whether it's coastal storms, inland flooding, or ice storms or tornado outbreaks in the southland, El Niño has the potential to adversely affect millions of Americans this winter (and potentially billions worldwide).
- A battery operated NWS Emergency Radio to find out what was going on, and to get vital instructions from emergency officials
- A decent first-aid kit, so that you can treat injuries
- Enough non-perishable food and water on hand to feed and hydrate your family (including pets) for the duration
- A way to provide light when the grid is down.
- A way to cook safely without electricity
- A way to purify or filter water
- A way to handle basic sanitation and waste disposal.
- A way to stay cool (fans) or warm when the power is out.
- A small supply of cash to use in case credit/debit machines are not working
- An emergency plan, including meeting places, emergency out-of-state contact numbers, a disaster buddy, and in case you must evacuate, a bug-out bag
- Spare supply of essential prescription medicines that you or your family may need
- A way to entertain yourself, or your kids, during a prolonged blackout
If not, you've got some important work to do.










