A rapidly growing sunspot group called AR4566 now sits almost dead center on the Earth-facing side of the Sun, and forecasters say it has the magnetic complexity to produce strong flares. NOAA's Space Weather Prediction Center (SWPC), in a joint report issued at 2200 UTC Sunday, Nov. 8 (5 p.m. EST), gave a 60% daily chance of M-class flares and a 15% daily chance of X-class flares for Nov. 9 through Nov. 11.

That X-class figure is down slightly from the 20% chance SWPC posted earlier in the weekend, and no X-class flare had occurred as of 12:40 UTC Monday (7:40 a.m. EST). The forecast wording remains measured: "Solar activity is likely to be moderate with a slight chance for an X-class flare on days one, two, and three," the report said.

For most households, this is a story about sky watching and radio signals, not about power or safety. The people who should pay the closest attention are amateur radio operators, pilots and mariners who rely on shortwave communication, precision GPS users, and aurora chasers in northern states.

A Tangled Magnetic Knot Near the Center of the Sun

AR4566 carries a "beta-gamma-delta" classification, the most complex category forecasters assign. A delta configuration means spots of opposite magnetic polarity are crowded inside the same dark umbrella of a sunspot. That tight squeeze stores magnetic energy that can suddenly release as a flare. Spaceweather.com said the region doubled in size over the weekend and "harbors energy for X-class solar flares."

SWPC's solar region summary, valid at the end of Nov. 7, measured the group at 360 millionths of the visible solar hemisphere with 28 individual spots. The region has also been busy. EarthSky logged an M3.5 flare from AR4566 that peaked at 18:33 UTC (1:33 p.m. EST) on Nov. 5.

Between Nov. 7 and Nov. 8, the Sun fired 20 flares, every one of them from AR4566, according to EarthSky's daily log. Three were M-class, the strongest an M1.9 that peaked at 18:42 UTC (1:42 p.m. EST) on Nov. 7. Each caused an R1, or minor, radio blackout on Earth's sunlit side. NOAA's GOES satellite data show seven M-class flares from Nov. 5 through Nov. 8 — and no X-class flare in the past week.

Location is part of the concern. SWPC's forecast discussion issued at 0030 UTC Nov. 9 placed the region just past the Sun's central meridian. A coronal mass ejection (CME) launched from near disk center is more likely to head toward Earth than one launched from the edge. So far, SWPC said, none of the region's eruptions has produced an Earth-directed CME.

A Coronal Hole Stream Is Already Stirring Minor Storms

The geomagnetic activity Earth is feeling right now has a different source. A stream of fast solar wind from a large coronal hole, an open region in the Sun's outer atmosphere, reached Earth over the weekend. SWPC said wind speeds peaked near 814 kilometers per second (about 1.8 million miles per hour).

That stream pushed the planetary K-index to 5, a G1 (Minor) geomagnetic storm, between 18:00 and 21:00 UTC (1 p.m. to 4 p.m. EST) on Nov. 7, and aurora was photographed over northern Minnesota. SWPC's joint report expects the field to be at "unsettled to minor storm levels on day one (09 Nov)," easing to active levels Nov. 10 and quieter conditions Nov. 11 as the stream fades.

G1 is the lowest step on NOAA's five-level geomagnetic storm scale. A larger storm would most likely require AR4566 to launch a CME aimed at Earth, which typically takes one to three days to arrive. No such watch has been issued. SWPC also gave a 15% daily chance of an S1 (Minor) solar radiation storm through Nov. 10.

Radio Blackouts, GPS Errors and Aurora Odds

A solar flare is a burst of light and radiation that reaches Earth in about eight minutes. It cannot be seen coming in advance, and its main effect is on the upper atmosphere over half of the planet in daylight. M-class flares typically cause R1 to R2 blackouts, brief degradation of high-frequency radio used by aviation, ships, and ham operators.

An X-class flare could bring an R3 (Strong) blackout, under NOAA's space weather scales, which can knock out high-frequency radio across the sunlit side of Earth for about an hour. Precision GPS used in surveying, aviation, and farm equipment can also lose accuracy during strong flares and geomagnetic storms, though phone navigation for everyday drivers is rarely affected in a noticeable way.

The current G1 conditions are a minor event. NOAA's storm scale says G1 storms can cause weak power grid fluctuations, which grid operators routinely manage, and minor effects on satellites. Aurora may be visible at high latitudes, typically along the northern tier from Washington and Montana to northern Michigan and Maine, away from city lights and with a clear view to the north.

Forecasters Are Watching for a Launch, Not Predicting One

It is important to read the numbers as odds — not a schedule. A 60% daily chance of M-class flares means moderate flares are more likely than not, but a 15% X-class chance means a strong flare is still unlikely on any given day. Sunspots can also simplify and decay, which lowers flare risk, or keep growing, which raises it.

SWPC said solar wind should stay elevated through Nov. 11 before coronal hole effects wane. AR4566 will rotate toward the Sun's western limb over the next week, and SWPC updates its forecast discussion daily at 0030 and 1230 UTC (7:30 p.m. and 7:30 a.m. EST).

No household action is needed. Aurora watchers in northern states should check SWPC's aurora forecast in the evening, and radio operators should expect occasional fadeouts during daylight hours. Nature World News will report any X-class flare, Earth-directed CME, or new storm watch.

What Readers Want to Know

What is sunspot AR4566? It is a large, magnetically complex sunspot group that NOAA classifies as beta-gamma-delta. It has roughly doubled in size over the weekend and is now facing Earth near the center of the Sun.

How likely is a strong flare? NOAA's forecast issued at 5 p.m. EST Nov. 8 gives a 60% daily chance of M-class flares and a 15% daily chance of X-class flares from Nov. 9 through Nov. 11.

Is a major geomagnetic storm coming? No major storm is forecast. Minor G1 storming from a coronal hole stream is likely Nov. 9. A stronger storm would require an Earth-directed CME, and none has been observed.

Will this affect my phone, GPS, or power? Unlikely for typical households. Flares can disrupt high-frequency radio and precision GPS on the daylight side of Earth, and G1 storms cause only weak grid fluctuations that operators routinely handle.

Where could the northern lights appear? Under G1 conditions, aurora is most likely in Alaska and along the northern tier of the U.S., including northern Minnesota, Michigan and Maine, from dark sites with a clear northern horizon.

When is the next official update? SWPC issues forecast discussions daily at 0030 and 1230 UTC, which is 7:30 p.m. and 7:30 a.m. EST.