NOAA Tracks M5.7 Solar Flare as Solar Flares May Reach Earth

An M5.7 burst of solar flares from sunspot region AR4436 peaked at 9:39 a.m. EDT on May 10, 2025, and sent a coronal mass ejection toward Earth. NOAA's Space Weather Prediction Center and the U.K. Met Office said part of the plume may brush past Earth around early May 13.

The flare triggered a radio blackout over the Atlantic Ocean. Forecasters said the glancing blow could still produce minor G1 geomagnetic storm conditions later this week, with auroras possible across the northern U.S. and the U.K.

AR4436 and Earth

AR4436 is rotating into Earth's strike zone on the sun's northeastern limb. That positioning gives forecasters a reason to keep watching the region, because NOAA and the U.K. Met Office said both additional M flares and X-class eruptions could occur over the coming days.

Solar flares are ranked A, B, C, M and X, with X the most powerful category, and each step on the scale represents a tenfold increase in energy output. The May 10 flare reached M5.7 strength, below X-class but still strong enough to disturb radio service when its X-ray and ultraviolet radiation ionized Earth's upper atmosphere.

May 10, 2024

The date also sits near a recent benchmark: on May 10, 2024, Earth experienced the first extreme G5 storm since 2003. That storm produced auroras visible as far south as southern Florida and Mexico.

This week's setup is weaker, but it still gives operators and sky watchers a narrow window. If the plume brushes past Earth as forecast, the main near-term effects are a possible aurora display and another round of high-frequency radio disruption rather than a repeat of last year's extreme event.

Early May 13

The next material change is the arrival window around early May 13, when part of the expanding plume may reach Earth. If that happens, the agencies' forecast calls for only minor G1 conditions, not the kind of severe storm that would drive the highest-end impacts seen in 2024.