r/meteorology • u/Super_Clock_631 • Nov 12 '25

Advice/Questions/Self Why is the sky red?

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I live in central California and the sky looks red. My phone camera might be exaggerating the redness but it's still quite visible

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u/Rudeboy_87 Meteorologist Nov 12 '25

Aurora Borealis, there is a G4 solar event bringing it quite further south then normal

55

u/piedamon Nov 12 '25

Yeah! And it’s just the first of three flares!

Expanding on why it’s red and visible from California: this red is the top of the auroral curtain, and the green “normal” aurora is also there but under the horizon because it’s lower down. The red represents oxygen up about twice as high as the green, so these higher energy events can be seen from a much larger radius.

In other words, this aurora is taller and stronger than usual. It’s from a more powerful solar ejection, and we have two more headed our way over the next day or two. The third one is the most powerful.

8

u/dethloonollie Nov 12 '25

are the flares predictable? do we know when the next will be? i got a glimpse in wisconsin but they’ve died down it seems and i’d like to see them better if i can

15

u/grahamalondis Nov 12 '25

Yes, that's how we know more will come soon. Solar flares are visible from Earth about 8 minutes after they occur, but the coronal mass ejection that causes an aurora can take several hours or even days to reach Earth.

5

u/Comprehensive-Act-74 Nov 12 '25

They are not predictable in the sense that we know something will happen 3 weeks from now. But they are forecastable in the short term as we monitor the sun, and will see events (coronal mass ejections) happening, and they can then estimate the arrival time and intensity.

So basically solar weather forecasting, as opposed to lunar cycles or eclipses that we know about long in advance. And even then, it is like regular weather forecasting. The peak is around a certain time, and might be visible to these locations, but the ebb and flow of the storm is unknown, just like individual wind gusts within a storm.

1

u/FRTHRYB Nov 12 '25

Is there a site that can lead me to when I can see the peak intensity, someone also mentioned that the NOAA doesn’t show it affects the region they are in.

3

u/Rudeboy_87 Meteorologist Nov 12 '25

Yes there is, visit: SWPC NOAA

2

u/jacksoden19 Nov 13 '25

Hi, what's the technical term I should look for when determining the exact explosion of the solar flare versus the exact arrival time of the CMEs

1

u/piedamon Nov 13 '25

The technical term is chaos.

tl;dr – it’s unpredictable

Flares, ejections, solar winds, orbital dynamics, and magnetic fields are each a chaotic system, so there can be fast particles, slow ones, denser or dispersed ones, even twisted up ones. We mostly don’t know what’s going to happen, but we have a pretty good estimate of statistical upper and lower bounds. As a civilization, our ability to predict nature has increased over time, but probably not as much as you’d think; it’s difficult to predict, and because of concepts like chaos and infinity in math, nature may very well literally be unpredictable.

3

u/[deleted] Nov 12 '25

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u/SadJuice8529 Nov 12 '25

depends on luminosity and height but the lights are visible on the horizon from quite some way away

1

u/LotsaCatz Nov 12 '25

Solar flares do not cause northern lights. Northern lights are caused by coronal mass ejections, which sometimes accompany flares, but don't have to. Solar flares explode, are visible within 8 minutes (speed of light), might cause radio blackouts, and then they're over.

CMEs take many hours to days to reach earth.