Understanding the Impacts of this Week’s Atmospheric River: A Comprehensive Map Analysis

November 5, 2025

Northwest Braces for Continued Impacts from Powerful Atmospheric River

A significant weather system, identified as a strong atmospheric river, is continuing to unleash substantial rainfall and associated hazards across portions of the Northwest United States. The National Weather Service (NWS) has been closely monitoring the situation, issuing alerts for moderate to heavy precipitation, potential flooding, strong winds, and mountain snow.

Current Conditions and Regional Impacts

Earlier this week, warnings were in effect across Northern and Central California as the atmospheric river initially made landfall, resulting in heavy rain, damaging winds, and considerable snowfall in mountainous regions. Recent data indicates that Northwestern coastal California and the southwestern Oregon coastline have already experienced between two and three inches of rainfall, with some localized areas receiving even higher amounts.

While Washington and Idaho have seen relatively lower rainfall totals, especially in valley areas, Oregon and Northwestern California remain the focal points of this weather event. Southern Washington Cascades have accumulated over an inch of rain, and certain parts of Oregon have seen accumulations approaching two inches.

Forecast: What to Expect in the Coming Days

The NWS forecasts continued rain and possible thunderstorms along the coastlines of California, Oregon, and Washington through Wednesday and into early Thursday. Beyond these coastal areas, portions of Idaho, Montana, Nevada, Utah, and Western Wyoming are expected to see mixed precipitation.

State	Expected Precipitation	Wind Gusts
California	1-4 inches (Coastal Mountains)	40-50 mph (Western & SF Bay Area)
Oregon	1-4 inches (Coastal Mountains)	40-50 mph (Western)
Washington	1-2 inches	40-50 mph (Western)
Idaho	Mixed Precipitation	Variable

Meteorologist Heather Zehr anticipates an additional one to two inches of rainfall across the region this week, with the potential for two to four inches in the coastal mountains. Wind gusts could reach 40 to 50 miles per hour in western Washington, Oregon, California (including the San Francisco Bay Area), and over higher terrain. A second storm system is poised to bring further rain and wind Thursday into Friday, with the most severe conditions expected on Thursday. Snow levels are predicted to decrease on Friday, but much of the snowfall is anticipated above pass level, though mixed rain and snow conditions could lead to slippery travel.

Understanding Atmospheric Rivers

Atmospheric rivers are characterized by the National Oceanic and Atmospheric Management (NOAA) as lengthy, concentrated bands of water vapor in the atmosphere. These systems are responsible for transporting the vast majority of water vapor outside of the tropics.A single atmospheric river can carry an amount of water vapor comparable to the flow of water at the mouth of the Mississippi River, and exceptionally strong systems can move up to fifteen times that volume.

While most atmospheric rivers deliver beneficial precipitation, the most powerful can cause extreme rainfall, flooding, mudslides, and substantial damage, especially when they stall over vulnerable regions. Did You Know? Atmospheric Rivers are a natural phenomenon and play a vital role in the water cycle of the West Coast.

Voices From the Field

Heather Zehr, AccuWeather Meteorologist: “A break in the wet weather is anticipated this weekend, with only minor showers expected early next week.”

The NWS stated on Wednesday: “The most active weather is occurring across the West, particularly near the coast, with multiple atmospheric rivers bringing periodic heavy rainfall to portions of the Northwest and Northern california. While the most significant rainfall and wind threats are diminishing today, a limited risk of severe weather exists in unstable air this afternoon. Precipitation will continue, increasing in intensity Thursday evening into Friday, though thunderstorms will be less frequent.”

Looking Ahead

The NWS will continue to provide regular forecast updates through its website and social media channels. Residents in affected areas are encouraged to stay informed and heed any official warnings or advisories. Pro Tip: Sign up for local emergency alerts to receive real-time updates during severe weather events.

The Increasing Frequency of Atmospheric Rivers

Recent research suggests that climate change may be influencing the frequency and intensity of atmospheric rivers. Warmer temperatures lead to increased evaporation, resulting in more moisture in the atmosphere, which fuels these events. Understanding these changing dynamics is crucial for effective preparedness and mitigation efforts. A 2023 study by the Scripps Institution of Oceanography indicated a measurable increase in the intensity of atmospheric rivers impacting the West Coast over the past several decades.

Frequently Asked Questions about Atmospheric Rivers

• what is an atmospheric river? An atmospheric river is a long, narrow band of water vapor in the atmosphere, responsible for transporting significant amounts of moisture.
• Are atmospheric rivers always dangerous? No, while powerful atmospheric rivers can cause flooding and damage, most deliver beneficial precipitation.
• How does climate change affect atmospheric rivers? Climate change may increase the frequency and intensity of these events due to increased evaporation.
• Where can I find the latest weather updates? The National Weather Service website ([https://www.weather.gov/](https://www.weather.gov/)) provides up-to-date forecasts and warnings.
• What should I do to prepare for an atmospheric river? Stay informed, heed warnings, and take steps to protect your property from potential flooding.

Do you have a preparedness plan for severe weather events in your area? share your thoughts in the comments below!

Stay safe and informed as this dynamic weather situation unfolds.

How do atmospheric rivers contribute to teh West Coast’s water supply, and what makes this week’s event particularly significant?

What is an Atmospheric River?

An atmospheric river (AR) is a long, narrow, and concentrated band of water vapor in the atmosphere. Think of it as a river in the sky, transporting massive amounts of moisture – sometimes exceeding the average flow of water at the mouth of the Mississippi River. These systems are crucial for replenishing water supplies, especially in western regions, but can also bring significant hazards. This week’s event is particularly noteworthy due to its intensity and duration. Key terms related to atmospheric rivers include Pineapple Express (an AR originating near hawaii), bomb cyclone (a rapidly intensifying low-pressure system often associated with ARs), and extreme precipitation.

current Atmospheric River – November 5th, 2025: A regional Breakdown

This week’s atmospheric river is impacting primarily the Pacific Northwest and California.Analyzing current weather maps reveals several critical features:

* Moisture Plume: A concentrated band of high atmospheric moisture content extending from the Pacific ocean towards the West Coast. Satellite imagery confirms this, showing significant cloud cover and precipitation.

* Low-Pressure System: A strong low-pressure system off the coast of Oregon is driving the AR inland. This system is exhibiting characteristics of a developing bomb cyclone, intensifying the rainfall.

* Orographic Lift: As the moist air encounters the coastal mountain ranges (Cascades, Sierra Nevada), it’s forced upwards, leading to enhanced precipitation. This orographic lift is a major contributor to the heavy rainfall and snowfall expected.

* Wind Patterns: Southerly winds are channeling the moisture directly into California and the Pacific Northwest. These winds are also contributing to increased wave heights and coastal erosion.

impact Assessment: State-by-State Analysis

here’s a breakdown of the expected impacts, as of november 5th, 2025:

California:

* Flooding: Major river systems, including the Sacramento, san Joaquin, and Russian River, are under flood watch. Urban flooding is also a significant concern, particularly in low-lying areas.

* Mudslides & Debris Flows: Saturated ground from previous storms increases the risk of mudslides and debris flows in hilly and mountainous regions. areas recently burned by wildfires are especially vulnerable.

* Snowpack: Heavy snowfall is expected in the Sierra Nevada, possibly boosting the state’s crucial snowpack. However, rapid melting following the storm could exacerbate flooding.

* Coastal Impacts: High surf and strong rip currents pose a threat to coastal communities.

Oregon & washington:

* Heavy Rainfall: Widespread rainfall exceeding 3 inches is forecast for many areas. This will lead to river flooding and potential landslides.

* Mountain snow: Significant snowfall is expected in the Cascade Mountains, impacting travel and potentially triggering avalanches.

* Wind Damage: Strong winds associated with the low-pressure system could cause power outages and tree damage.

Nevada:

* Localized Flooding: While further inland, Nevada may experience localized flooding due to runoff from the Sierra Nevada.

* Increased Snowpack: higher elevations in Nevada will benefit from increased snowpack.

Mapping Tools & Resources for Real-Time Tracking

Staying informed is crucial. Here are some valuable resources for tracking the atmospheric river:

1. National Weather Service (NWS): https://www.weather.gov/ – provides official forecasts, warnings, and real-time observations.
2. NOAA’s Weather Prediction Center: https://www.wpc.ncep.noaa.gov/ – Offers detailed analysis and forecasts of large-scale weather systems.
3. integrated Flood Hazards Mapping: https://msc.fema.gov/portal/home – FEMA’s mapping tool for identifying flood risk areas.
4. Windy.com: https://www.windy.com/ – A visual weather mapping platform showing wind, precipitation, and other atmospheric variables.
5. Local News & Emergency Management Agencies: Stay tuned to your local news and follow guidance from emergency management officials.

Ancient Precedent: the January 2023 California Floods

The current atmospheric river bears similarities to the series of storms that impacted California in January 2023. These storms caused widespread flooding, landslides, and power outages, resulting in billions of dollars in damage and multiple fatalities. The 2023 event highlighted the vulnerability of California’s infrastructure to extreme precipitation and the importance of preparedness.Lessons learned from 2023 are informing current response efforts,including proactive reservoir management and evacuation planning.This event serves as a stark reminder of the potential consequences of atmospheric rivers.

Benefits of Atmospheric Rivers (and Why We Need Them)

Despite the hazards, atmospheric rivers are vital for the West Coast’s water supply. They contribute to