Sun CME tracker: read the reports and prepare for disruption

Start with the tracker, then check the official forecast

A useful tracker answers a sequence of questions: what was observed, when was it observed, was an Earth encounter modeled, and how recently was that assessment revised? Those questions are more useful than counting every eruption as a threat. This guide is an evergreen explanation, not a report of today’s solar conditions.

A CME, a flare and a radiation storm are different

A coronal mass ejection is an expanding cloud of plasma carrying magnetic field away from the Sun. A flare is a burst of electromagnetic energy. Accelerated energetic particles can produce a solar radiation storm. These phenomena can occur together, but their travel, effects and severity measures differ. NASA’s solar-storm explainer describes the distinctions.

The NOAA scale tables describe possible system effects. A high category deserves attention, but does not establish a restoration time, household risk percentage or universal equipment failure. Earth’s atmosphere and magnetic field protect people at ground level from these solar radiation hazards. A solar alert is not a reason to take potassium iodide or follow a fallout decontamination procedure.

Read the time and the uncertainty together

NOAA explains that the fastest Earth-directed CMEs can arrive in roughly 15–18 hours, while slower events can take days. Direction, speed and the embedded magnetic field matter. Strong, sustained southward magnetic field favors greater geomagnetic disturbance; a speed number alone cannot tell you the outcome. See NOAA’s CME explanation.

• Observation time: when an instrument first reported the event, not when it reached Earth.
• Analysis or update time: when the interpretation was produced. A revised record can change the arrival estimate.
• Modeled arrival: an estimate from a particular analysis, not confirmation that an impact occurred.
• Timezone: compare UTC with your local time before arranging a check-in. Do not silently treat a UTC date as a local calendar day.
• Missing arrival: information is absent from the selected record. That is neither a confirmed miss nor an all-clear.

Our tracker draws on NASA CCMC DONKI research information. NASA labels these products experimental and identifies NOAA as the official US forecast source. The expanding front and Earth orientation help explain the report; they cannot identify a first country struck or show a live physical shock boundary.

Turn a warning into a short household check

The National Weather Service recommends an emergency kit and a family communication plan for possible loss of electricity during an extreme solar event. It also cautions that most G5 storms do not cause catastrophic grid damage. The practical response is to review essential services and the people who depend on them. NWS preparation guidance.

1. Charge the phone and any backup battery you already own; put the correct cable with each device.
2. Write down an out-of-area contact, a check-in time and a meeting arrangement if messages fail.
3. Find the household lights, spare batteries, water and ready-to-eat food. Make them accessible to everyone who needs them.
4. Save essential addresses and route notes offline. Keep a paper copy of the information you would lose with a flat phone.
5. Check utility notices and local emergency information. Treat an actual outage according to local conditions, including heat or cold.
6. For electrically powered medical equipment, confirm the supplier-supported backup and relocation plan before a warning becomes urgent.

A practical rehearsal is to ask another household member to find the light, contact sheet and charging cable without your help. Record any missing item. This exercise identifies concrete gaps without requiring a new purchase.

Budget backup power around the job

Begin with communication and lighting loads. A small phone battery is not a substitute for a refrigerator supply, home air conditioner or a medical-device plan. An illustrative 500 Wh power station with an assumed 85% usable fraction and a constant 25 W load gives 500 × 0.85 ÷ 25 = 17 hours. That is arithmetic, not a tested product runtime.

Check the device’s real load, connector, voltage and the power source’s continuous and surge ratings. Temperature, idle draw and battery condition can change available energy. A powered router still needs a working upstream network. Use the battery runtime calculator and backup-power explainer to document the assumptions.

During an outage, follow the power-outage guide. Fuel generators must operate outdoors, at least 20 feet from doors, windows and vents; never use one inside or in a garage. CDC generator guidance.

Choose equipment for an ordinary service interruption

Our two examples below serve specific roles: a broadcast receiver for instructions and a headlamp for hands-free light. We checked manufacturer documentation; we have not tested reception or runtime ourselves. A radio is useful only if it receives a suitable local station from its intended location. Spare cells and a familiar light may be all that is missing from an existing kit.

We do not recommend specialty shielding bags solely because a CME appears in a tracker. A shopping label cannot establish how a particular device will behave in a particular space-weather event. Likewise, a new power station is justified by a documented load and charging plan, not the dramatic appearance of the animation.

A five-minute review after the alert

• Read the latest NOAA update rather than a screenshot of an older forecast.
• Check whether the utility has reported an actual local disruption.
• Recharge used equipment once power is safely available.
• Write down failures in reception, cables or household communication.
• Replace only what the rehearsal or interruption showed was missing.

For the related hazards, read extreme heat preparedness when cooling might fail, and radiation emergency preparedness for a separate explanation of radioactive contamination incidents. The correct first action depends on the actual hazard.