Thursday, the Space Weather Prediction Center issued a Geomagnetic Storm Watch in response to a powerful solar flare which produced a Coronal Mass Ejection (CME) that is heading towards Earth. So now in English, the sun is on fire (as it should be), and it just threw a ball of plasma in our direction (it happens). But don’t panic just yet – we actually celebrate these things.
These big balls of solar plasma (CMEs) are what cause outbursts of northern lights in areas where aurora displays are not common. The chances of a New York state aurora display this weekend are probably only around 25% if I had to guess, but that’s better than I’ve seen in months. So if you’ve got time to kill this weekend, and enjoy amazing spectacles that are full of bright, vivid colors, read on – the chart below is all you’ll need to figure out if you should look to the north. If you’re not into amazing sights but still have time to kill, simply turn off your computer, but continue to stare at your monitor. I’ve heard that does the trick.
Above is what we call the Kp Index, which is provided by the Space Weather Prediction Center (SWPC). Every three hours, the SWPC updates this chart with a new colored bar on the right. There will be up to 8 colored bars in one 24-hour period – no colored bar equals a Kp of zero. To translate the colored bars into aurora likeliness, the three rules below are my own personal understanding of this index. For the SWPC’s official explanation, follow this link.
Decoding The Kp Index
If the latest (rightmost) colored bar is:
- GREEN, (Scale of 1 – 3): Auroras might be visible at very high latitudes (Canada, Alaska).
- YELLOW, (Scale of 4): Auroras might be visible at high latitudes (Canada).
- RED, (Scale of 5 – 9): A Geomagnetic Storm is in process, and auroras might be visible in the US. See the pattern unfolding? The higher the number, the further south auroras might be visible.
* Notice use of the word might.
Northern Lights in Rochester, NY
Since most of our readers live in Rochester, NY, I’m going to make it even easier if you fall into that group. Rochesterians, here’s the deal:
- Rochester, NY, Kp = 6: When the scale reaches 6, that’s normally when I’ll go out to look. But 6 is a stretch. I often strike out with a Kp of 6 from my house, but I have heard of people seeing auroras across Lake Ontario when the Kp is at 6.
- Rochester, NY, Kp = 7: If you’re catching on to this whole Kp thing, then I probably don’t have to tell you that a 7 is looking pretty darn good. But normally when I see a Kp of 7, the sky is either clouded over, or it’s 9 o’clock in the morning, or the moon is so bright that you could read a book outside! Luckily, the skies this weekend in Rochester should be clear and the moon is almost new. However, timing is still everything – a Kp of 7 doesn’t help if it’s mid-day.
Other Info: For a map showing the correlation between Kp and other US locations, click here. For the Space Weather mother-lode, see the SWPC’s education links. Also, feel free to email me with any questions. Keep your fingers crossed!