Article image

Earth prepares for solar storm impact from three CMEs this weekend

Solar activity has reached high levels in the past 24-36 hours, with background flux at or near M1.0. The most significant developments from the Sun include the growth and merging of Regions 3664 and 3668, as well as the production of numerous M-class solar flares and two X-class solar flares from CMEs that are expected to arrive at Earth this weekend.

Region 3664 dominates solar activity with three CMEs

Region 3664, now combined with Region 3668, has grown to over 1,500 miles in size. This region has been the primary source of solar activity, producing many M-class flares and two X-class flares.

Associated with this activity were three halo coronal mass ejections (CMEs) expected to arrive on Earth between late May 10 and early May 11, 2024.

A fourth halo CME, linked to the X2.2/3B flare, is visible in STEREO imagery but has yet to be fully analyzed due to pending updates in LASCO coronagraph imagery.

Sunspot region 3663 shows signs of decay

Region 3663, approaching the western limb, exhibited signs of decay and appears to be losing its delta configuration.

Despite this, the region continued to produce optical flares, radio bursts, and an isolated M-class flare. Other spotted active regions remained stable and inactive.

Solar filament eruption and CME

In addition to the activity in Regions 3664 and 3663, a 35° long filament erupted near E27N18. This eruption was accompanied by a CME moving primarily in a northeasterly direction.

Analysis suggests a possible Earth-directed component with timing similar to the aforementioned halo CMEs.

Forecast: High to very high solar activity expected

Solar activity is expected to persist at high to very high levels from May 9-11. M-class flares (R1-R2/Minor-Moderate) are expected, and X-class flares (R3/Strong) are likely due to the continued flare potential of Regions 3663 and 3664.

Energetic particle activity and forecast

Electron and proton flux levels

The greater than 2 MeV electron flux remained at normal to moderate levels, while the greater than 10 MeV proton flux was steady at background levels.

Forecast: Potential for minor proton flux storm

The greater than 2 MeV electron flux is expected to continue at normal to moderate levels from May 9-11, 2024.

There is a chance for the greater than 10 MeV proton flux to reach S1 (Minor) storm levels during this period due to the flare potential of Regions 3663 and 3664.

Solar wind conditions and forecast

Near-background conditions with elevated solar wind speeds

The solar wind environment reflected near-background conditions, with slightly elevated solar wind speeds likely attributed to residual coronal hole high-speed stream (CH HSS) influence.

Total field strength remained steady near 3 nT, the Bz component had no significant southward deflections, Phi maintained a positive orientation, and solar wind speeds averaged near 470 km/s.

Forecast: Enhancements expected from CME arrivals

Enhancements in the solar wind environment are likely on May 9 following the anticipated glancing effects of a CME that departed the Sun on May 6. Stronger enhancements are expected late on May 10 and into May 11 as the two CMEs that left the Sun on May 8 are anticipated to arrive at Earth.

Geomagnetic activity and forecast

Quiet geomagnetic field

The geomagnetic field remained at quiet levels over the past 24 hours.

Forecast: Unsettled to strong geomagnetic storm conditions

From mid to late day on May 9, unsettled to active conditions are possible as glancing effects from the May 6 CME influence Earth.

By late May 10, the arrival of the two halo CMEs from May 8 is expected to increase the geomagnetic response to G1 (Minor) storm levels.

Early on May 11, conditions are likely to reach G3 (Strong) or G4 (Severe) storm levels as the bulk of four CMEs moves past Earth.

While confidence in timing is fairly high, confidence in the magnitude and strength of the geomagnetic response to the CME arrival is low to moderate.

Please refer to this chart for an explanation of the NOAA Weather Scales.

Potential impacts

The area of impact is primarily poleward of 50 degrees Geomagnetic Latitude. Potential effects include:

  • Induced Currents: Power system voltage irregularities and false alarms on some protection devices.
  • Spacecraft: Surface charging and increased drag on low Earth-orbit satellites, potentially causing orientation problems.
  • Navigation: Intermittent satellite navigation (GPS) problems, including loss-of-lock and increased range error.
  • Radio: Intermittent HF (high frequency) radio communication.
  • Aurora: Northern lights may be seen as low as the southern states, down to Iowa in the Midwest, and down to Oregon in the Northwest.

Earth braces for impact from another solar storm

In summary, as the Sun continues to showcase its immense power through high levels of solar activity, Earth prepares for the potential impacts of incoming CMEs.

While the timing of these events remains fairly certain, the magnitude of their effects on our planet’s geomagnetic field is still a subject of speculation.

Regardless of the outcome, this period of heightened solar activity serves as a reminder of the intricate relationship between our star and the technology we rely on daily.

As we monitor the developments in the coming days, it is crucial to remain vigilant and prepared for any challenges that may arise from this cosmic dance between the Sun and Earth.

Stay tuned to and the NOAA’s Space Weather Prediction Center (SWPC) for updates.


Like what you read? Subscribe to our newsletter for engaging articles, exclusive content, and the latest updates.

Check us out on EarthSnap, a free app brought to you by Eric Ralls and


News coming your way
The biggest news about our planet delivered to you each day