Alert for Severe Solar Storm Impact

By Elaine Shein, DTN/Progressive Farmer Associate Content Manager, and Dan Miller, Progressive Farmer Senior Editor

OMAHA (DTN) -- The Space Weather Prediction Center (SWPC) has issued a rare G4 severe geomagnetic storm alert for June 1-2, after the storm strengthened and reached G4 conditions. This is the result of several coronal mass ejections (CME) of solar material and strong magnetic fields; the largest that erupted left the sun on May 30 near 7 p.m. CDT. That CME moved very quickly at an estimated around 1,194 miles per second -- 4.3 million mph -- to cause a severe geomagnetic storm and auroras (northern lights) to be seen much farther south than normal.

SWPC said the CME arrived earlier than originally thought, close to 12:30 a.m. CDT Sunday. "The potential for elevated geomagnetic response remains dependent upon the strength and orientation of the embedded magnetic field, but the potential exists for Severe Storm levels."

"While this event (an R2, M8 solar flare) has the potential to become a significant geomagnetic storm, SWPC believes it is unlikely to reach the intensity of the May 2024 (G5) event," the center posted near 4 a.m. CDT Sunday. (On the G-scale, G1 is a minor storm, G5 most extreme.)

The geomagnetic storm alert is for G4 (Severe) for June 1-2, then the storm levels are expected to subside June 3 to G1-G2 (Mild to Moderate) still possible. However, SWPC noted people should visit its website for the latest information and updates. (https://www.swpc.noaa.gov/…)

REACHED SEVERE LEVEL OVERNIGHT

SWPC said the geomagnetic storm had strengthened and G4 levels of the storm were reached overnight. It added, regarding possible technology effects, "Infrastructure operators and authorities have been notified to take action to mitigate any possible impacts and for situational awareness. Possible increase and more frequent voltage control problems -- normally mitigable. Increased possibility of anomalies or effects to satellite operations. More frequent and longer periods of GPS degradation possible."

Near 9:30 a.m. (CDT) on Sunday in an updated message on its site, SPWC warned of a potential impact area "primarily poleward of 45 degrees geomagnetic latitude." It added this could include "Possible widespread voltage control problems and some protective systems may mistakenly trip out key assets from the power grid," along with an "increased drag on low earth orbit satellites, and tracking and orientation problems may occur. Satellite navigation (GPS) degraded or inoperable for hours. HF (high frequency) radio propagation sporadic or blacked out. Aurora (northern lights) may be seen as low as Alabama and northern California."

With the G4 levels reached overnight on Saturday, aurora (northern lights) was expected to be visible over much of the northern half of the country, although in some areas the wildfire smoke from Canada and clouds affected ability to see the aurora. Space.com reported that people saw aurora as far south as California and New Mexico Saturday night; chances continue to be good to see them again on Sunday night.

POWERFUL STORM YEAR AGO

On May 10, 2024, farmers who were planting were affected by a powerful geomagnetic storm that affected Canada and the U.S.

The Kansas State University Research and Extension News Service recently published a release about that event.

That storm came to be called the Gannon Storm. It caused "mass global navigation satellite system outages ... leading to an assumed $565 million in losses for Midwestern crop producers," the K-State release reported.

K-State precision agricultural economist Terry Griffin cautioned the 2024 storm may be more than a once-in-a-lifetime event.

"It's probably what we should expect moving forward, not just for the next solar cycle, but also for this spring because we haven't passed the maximum amount of geomagnetic disturbances for the solar cycle yet," said Griffin, in the release. "Spring 2025, fall 2025 and even spring 2026, we should still expect this type of activity."

The sun is the main source of space weather. Radio emissions, coronal mass ejections (CMEs), and solar flares are some of the causes of geomagnetic storms.

Storms are more common during solar maximums. The peak of sunspot activity is known as a solar maximum. The lull is known as solar minimum. Maximums and minimums occur on average in 11-year cycles. Earth is approaching the peak of the current solar maximum that began in 2020. The peak should occur in summer 2025, although some experts are now speculating this solar maximum could last into next year.

Radio frequency disrupting flares reach Earth at the speed of light. CMEs travel more slowly, taking one to five days to reach Earth. Both can disrupt communications, the power grid, navigation, radio and satellite operations for minutes, to hours or days at a time.

IMPACT ON GPS, WHAT FARMERS CAN DO

A complete loss of signal lock by the GPS receiver due to extreme noise from the upper atmosphere (primarily nighttime) can result in no location data for an interval of time. Noise introduced by the upper atmosphere also could have induced errors in the calculated position.

Like a thunderstorm, farmers can only manage their systems through GPS-battering geomagnetic storms. Newer positioning systems that lock onto multiple satellite constellations are little to not affected by solar storms.

With older navigation systems, farmers may bring a stop to fieldwork and wait for the storm to pass, often in hours. Or farmers can grab the steering wheel and just plow through, accepting crooked rows and any planting and data collection inaccuracies that follow.

But without GPS, the as-planted data (as-sprayed, as-fertilized) cannot be logged onto a map or georeferenced. This isn't just a negative result for farm operators. Seed suppliers and local agronomists rely upon these data for upstream use.

Here are specific actions you can take.

-- Understand what part of any equipment or data system relies on GPS or radio frequencies (RF), and how resilient that equipment is to RF/GPS noise. Are your GPS receivers single or dual frequency receivers? Single frequency receivers are more susceptible to space weather.

-- Have a short-term local data backup system. Similar to commercial security system that records everything and then deletes it after a certain time period, data would go to both the cloud and a short-term, local backup system that could be recovered if the connection to the cloud is compromised.

-- Sign up for space weather alerts/watches/warnings at the NOAA Space Weather Prediction Center. Go to https://www.swpc.noaa.gov/… or just to www.swpc.noaa.gov.

-- If an issue is noticed with the GPS systems look at the NOAA alerts or the Navigation Centers civilian GPS outage reports (https://www.navcen.uscg.gov/…) to determine whether the source is environmental or a hardware problem.

-- If there is elevated space weather, and local hardware issues have been ruled out, report outage to the Navigation Center through the on-line reporting: https://www.navcen.uscg.gov/….

It is important that the nation has a good understanding of how space weather affects users.

For the complete K-State Research and Extension release featuring Griffin go to: https://ksre-learn.com/…

Elaine Shein can be reached at elaine.shein@dtn.com

Follow her on social platform X @elaineshein

Dan Miller can be reached at dan.miller@dtn.com

Follow him on social platform X @DMillerPF

(c) Copyright 2025 DTN, LLC. All rights reserved.