Don’t Let Space Weather Catch You Off Guard 

By Joan Conover 

The sun is waking up — and cruisers need to pay attention. With the current rise in solar activity, we are seeing National Oceanic and Atmospheric Administration (NOAA) issue more and higher geomagnetic storm watches. These are triggered by coronal mass ejections (CMEs) and high-speed solar wind streams — powerful outbursts from the sun that can disturb Earth’s magnetic field and disrupt satellite and other earth-based systems.  

What does this mean to you? It can mean impacts to GPS locations for your electronic chartplotter, autopilot guidance and other electronics. These devices depend on the precise latitude/longitude/time that GPS provides. GPS errors can affect how your devices guide your boat or car. At the same time, your internet and communications may have errors, meaning slow and/or suddenly offline issues, or noisy radios.  

Locations may seem to change suddenly, your anchor alarm may go off — as much as 180 degrees from true location. Automatic Information System (AIS), used to send your location to other boats, operates off VHF radio as well as satellites, so it can have errors. Any electronic device, if not shielded, can exhibit abnormal behavior. Power may be affected and more.  

And it’s not just navigation. Internet speeds can slow, HF and VHF radios may experience static or dropouts, and even power grids ashore can suffer voltage instability during severe events.  

The Space Weather Prediction Center (SWPC), part of NOAA, monitors these space weather events. When a geomagnetic storm reaches Earth, it can distort the signals sent between GPS satellites and your onboard systems. Again, this means your electronic chartplotter, autopilot, and anchor alarm — all of which depend on precise GPS coordinates and time sync — may suddenly behave erratically.  

For example, during the May 2024 solar storms, cruisers in the Bahamas reported sudden 180-foot shifts in their GPS position — despite sitting at anchor. Anchor alarms were triggered. Chartplotters showed vessels drifting when they were stationary. Autopilot systems, which rely on GPS for track guidance, began veering off course. And this is usually worse in the tropical latitudes.  

2026 Solar Activity Update 

From January 19-22, 2026, NOAA’s Space Weather Prediction Center tracked a prolonged solar disturbance lasting roughly 72 hours. Unlike short-duration impulse events, this episode was marked by sustained elevated solar proton levels, periods of severe geomagnetic activity (Kp reaching 8-9, G4-G5), and continued disturbance of the ionosphere. Two strong X-class flares (X8.1) occurred during this broader active period; while their immediate impacts were primarily radio-related, the overall duration of the storm increased the likelihood of navigation and communications anomalies persisting well beyond a single watch cycle. 

Field reports from SSCA vessels operating in the Caribbean during this period — including at relatively low latitudes — noted intermittent anchor alarm activations, subtle but persistent position and heading “wander” on electronic displays, and short-term inconsistencies between GPS, compass heading, and visual reference. These effects were non-catastrophic but operationally disruptive, particularly for vessels relying heavily on integrated navigation systems. As with prior events, this reinforces the importance of visual reference, cross-checking electronic data, and heightened situational awareness during extended periods of elevated solar activity. 

And note the sudden intensification of weather systems, which (theory says) could have been caused by those same solar features. On June 28, 2024, Hurricane Beryl shocked forecasters and those of us assisting in the islands in the impact area, by rapidly intensifying from a tropical storm to a major Category 3+ hurricane in less than 24 hours. While warm sea surface temperatures played a key role, NOAA’s Space Weather Prediction Center (SWPC) also noted elevated geomagnetic activity during the same period. Emerging research suggests that solar storms may influence atmospheric conditions, such as high-altitude heating and jet stream shifts, that can subtly alter hurricane development. Although still under scientific review, some meteorologists are now exploring the potential correlation between solar outbursts and unexpected storm intensification. (Source: NOAA SWPC, May 2025 Solar Event Report; NHC Beryl Advisory #9A).  

One such study is titled “Rapid Intensification of Tropical Cyclones in the Context of the Solar Wind–Magnetosphere–Ionosphere–Atmosphere System,” published in Advances in Space Research. This research examines how solar wind coupling to Earth’s magnetosphere and atmosphere may influence the rapid intensification of tropical storms. Find the article online at sciencedirect.com/science/article/abs/pii/S1364682618305765. 

Best advice? Stay aware and check out swpc.noaa.gov, which has satellites providing direct feeds you can view and an alert system you can subscribe to: 

Subscribe to NOAA SWPC Alerts. Sign up at swpc.noaa.gov and sign up for email alerts. Receive real-time warnings for solar flares, geomagnetic storms, and solar radiation events.  

Know the impact scales most geomagnetic storms are G1-G5. Geomagnetic storm strength (G2 and above can affect GPS and HF radio). There are also warnings for radio and aviation. May 2024 disruptions were a G4, for example. October 2024 was also a G4 with extended impacts. 

 Check before a passage. Before heading offshore or entering narrow channels, make it a rule to check the SWPC forecast page or check your alert email. Avoid relying solely on autopilot or GPS-dependent features during high-activity windows. 

Stay manual-capable and aware of your location and have situational awareness on the water. 

For mariners, especially those relying on modern navigation and communication, space weather has implications to be aware of. Don’t let space weather catch you off guard. Many calls for radio problems, noisy or unusable channels come down to interference, and the sun can be the cause. NOAA’s SWPC is your early warning system. Subscribe to the automatic alert system, stay aware, and remind others in your anchorage to do the same. It’s not usually a huge impact, unless you are transiting a narrow cut; of course an anchor alarm at midnight is a concern for us all. Follow navigation rules — have a watch on passage. It’s a rule for a reason. 

Joan Conover, the president of the Seven Seas Cruising Association, sails aboard SV Growltiger.