Space weather today

The week ahead

Active. That is the verdict for this week, and very nearly all of it gets spent on Monday.

NOAA has today topping out at a Kp of 5, the doorstep of a Minor (G1) storm, which also happens to be the ceiling for the entire week. Then the Sun exhales. Tuesday eases to Kp 3, and Wednesday through Sunday sit at Kp 2, which is the space-weather equivalent of a flat, cloudless week. (Fair warning on that 5: NOAA's shorter three-day outlook caps Kp at 4.67, and their storm-scale table lists no geomagnetic storm level at all for today through Wednesday. Monday is the edge of Minor, not a promise.)

On the radio side, there is a 20% chance of a Minor (R1) blackout today, tomorrow and Wednesday, with the odds of anything larger sitting at 1% on each of those days. Past Wednesday NOAA stops handing out numbers, and so will I. The shape of the week says calm, and I would rather tell you that plainly than dress it up in a percentage nobody measured.

What it means for you

• Heart & sleep: Researchers keep noticing that unsettled geomagnetic days line up with rougher sleep for some people, so if tonight is a restless one, log it, keep your normal routine, and know the rest of the week looks quiet.
• Mood & focus: If Monday feels a little foggier than it has any right to, you are allowed to notice that without turning it into a diagnosis; by Wednesday the Sun has nothing left to blame.
• Preppers, radio & GPS: That 20% Minor (R1) window today through Wednesday means brief high-frequency fadeouts on the daylit side of the planet, so check your bands before you rely on them and expect nothing worse than a nuisance.
• Aurora-chasers & the spiritually curious: Monday's Kp of 5 is your only realistic shot this week, and only from high latitudes with a clear northern horizon; after that the sky goes back to its day job.

Last week on the Sun

Last week the Sun made good on a threat it had issued days earlier. The Kp index peaked at 5.67 on Sunday afternoon UTC, and NOAA logged the week's high-water mark as a Moderate (G2) storm: one storm period, one storm day, out of 55 Kp readings. Short, sharp, done.

The cause was the week's largest flare, an M1.9, a long slow burner rather than a quick pop. It arrived in company, with a partial-halo cloud of solar material and a filament peeling off the Sun's face at roughly the same moment. Part of that cloud had our name on it, and it landed Sunday.

The thing worth knowing from last week is that the flare, the coronal mass ejection and the filament eruption all came out of the same busy neighborhood of the Sun within minutes of each other, which is why a modest M-class flare punched so far above its weight. Size is not everything with these. Direction is. And the direction was us.

Looking further out, NOAA expects solar activity to stay predominantly low in the weeks ahead, with an ongoing chance of minor radio blackouts. Quiet-ish, in other words, with the usual asterisk: the Sun does not file a flight plan. Which is the whole reason this lands in inboxes every Monday, and if you would like it in yours for free, you can sign up for the weekly forecast and let us watch the sky on the weeks you would rather not.

Forecast data: NOAA SWPC