How Aurora Forecast USA Works | Methods & Sources

Short answer

Aurora Forecast USA combines published geomagnetic information with local cloud cover, moonlight, darkness, and magnetic-latitude context. It helps plan a viewing attempt; it cannot confirm that aurora will be visible at a particular place or time.

Data Sources

NOAA Space Weather Prediction Center (SWPC)

Our primary space weather data comes directly from NOAA's Space Weather Prediction Center, the US government's official source for space-weather products. We use NOAA products as source context for current and forecast geomagnetic conditions, including its aurora forecast map.

Kp Index

The planetary Kp index is the standard measure of geomagnetic disturbance on a 0-9 scale. Higher Kp values can extend the auroral oval farther south. Kp is one planning signal, not a local visibility measurement. We also reference Kp products published by GFZ Potsdam where available.

Cloud Cover

Even during strong geomagnetic storms, clouds will block your view of the aurora. We use local cloud forecasts as a visibility factor. Cloud providers publish on their own schedules, and local weather can change between updates.

Moon Phase & Illumination

A bright moon can make faint aurora harder to see. We show moonlight and local rise/set context as planning information.

Sky Darkness

Aurora is usually easier to see in darker conditions. Local twilight times help identify a useful viewing window, alongside horizon and light-pollution conditions.

Magnetic Latitude

Geographic latitude alone does not determine aurora visibility; magnetic latitude matters more. Magnetic north is offset from true north, so locations at similar geographic latitude can have different aurora context. City thresholds are estimates for planning, not a promise of visibility.

How we combine signals

We present five practical signals together so you can evaluate a viewing opportunity:

Geomagnetic activity — NOAA and GFZ source products compared with city context
Cloud cover — local weather forecast conditions
Moonlight — illumination and local timing context
Darkness — local sunset and twilight context
Magnetic latitude — an estimate of a location’s relative auroral reach

Conditions and source products can change quickly. Always assess the latest data with your local sky and horizon; no status or threshold guarantees a sighting.

Source cadence and site checks

NOAA and GFZ: each publisher controls its own product cadence and timestamps.
Weather: forecast providers publish at their own cadence; rapid local changes remain possible.
This site: checks available upstream data periodically. A site refresh is not a new observation or forecast issued by a source.

Coverage

Aurora Forecast USA provides US city and regional forecast pages. Geographic coverage and available locations can change; use search to find the local page closest to you.

Accuracy & Limitations

Aurora forecasting is inherently uncertain because it depends on solar activity that can change rapidly. Our algorithm provides the best estimate given current data, but surprises, good and bad, happen regularly. We recommend:

Checking NOAA, GFZ, and local weather timestamps close to when you plan to go outside
Rechecking conditions if the forecast or weather changes
Having a backup plan if cloud cover moves in
Using our app for real-time push notifications when conditions improve

Editorial ownership and corrections

Methodology is written and maintained by Nikolai Iakubovskii for AuroraMe. We describe source products and how they are used without representing NOAA, GFZ, or weather providers as endorsing this site. To report an error or request a correction, use our contact page. See our editorial policy and US visibility data for related context.

Learn More

Explore aurora forecasts for popular US cities:

Fairbanks, Alaska — prime auroral zone
Anchorage, Alaska — frequent aurora displays
Seattle, Washington — visible during strong storms
Minneapolis, Minnesota — occasional northern lights
Chicago, Illinois — rare but possible during major events
Denver, Colorado — only during extreme storms