According to the SWPC[0], the "SPACE WEATHER CONDITIONS" section displays the pertinent information: as of 5/10/2024 at 6:00 CST, the "24-Hour Observed Maximums" list "R3 S2 G4". The "Latest Observed" section shows "R1 S1 G4".
According to NOAA Space Weather Scales [1], the effects of those events, their levels, and the corresponding hazards (including biological risks for the "S" category) are listed.
It is unclear to me what "high-flying" and "high latitudes"
mean in these cases, and I would think that they would depend on the severity and location of the space weather event.
In general, not related to this event, anything over FL410 (roughly 41,000ft) and closer to the pole than 70 degrees latitude would be considered high altitude and high latitude in the aviation world.
Above FL410 is rare, except for business jets that can cruise that high. It comes with extra requirements on oxygen masks etc.
Polar routes are not that rare, but depend on certification how far away from a suitable airport you can go.
Nothing consequential for a single flight. Even crew really don't have to worry about it until it gets to very high levels, according to the NOAA scales
FWIW I'm an aircraft mechanic and the only complaint I've ever heard related to solar storms was that the HF radio stopped working. Which isn't a radio thats going to be used or even installed on a typical airliner.
Although it could also disrupt satellite communication causing some delays in flight planning and aircraft/crew turnaround.
For a fun anecdote, when the HF radio fault was reported we weren't aware of the troubles in the ionosphere. After a few hours of troubleshooting on the system and not finding any problems I flippantly remarked that it must've been a solar flare because the radios perfect. 15 minutes later I was reading the news and saw the headline.
HF is installed on many airliners, it's mandatory for the North Atlantic routes between the US and Europe. Still checked every flight as a backup to satellite position reporting (which is relatively new)
You can look at the current activity charts and extrapolate from the particle flux, but it's likely going to be below 1mSv for a 6 hour flight. The XKCD radiation chart provides the most sensible comparison for most people I think:
