Predicting for the Naked Eye Viewing Experience

When I write about forecasts for Northern Lights in the Great Lakes region, I give predictions with the naked-eye viewer in mind. In my forecasting updates, I also cater to beginners.

Find out: “What kind of Aurora Chaser are you?”

In the Michigan Aurora Chasers, this means drawing upon my experience of actually seeing the Northern Lights around the state, recognizing that some locations and latitudes are much more difficult for first-time Aurora sightings, and forecasting modestly.

I will boldly make a claim:
On Friday, July 14 into early Saturday, July 15, there is a slight chance the U.S. could see Aurora at a strength of Kp5, for example. That would bring visible Aurora as far south as the 45th Parallel.

Wait. Read that again. Now, stop.

Let’s look at that claim, and tear it apart!

On Friday, July 14, there is a chance the U.S. could see Aurora at Kp5, but other factors that inform how well Aurora appear could make this event visible much farther north, or much farther south. For example, if the Bz — known as “the gatekeeper” to the Aurora — does not cooperate, this event may only be visible in Canada. Womp, womp. And what if Aurora does come this far south, but it is not visible?! Enter “camera-only “sightings.

Tearing it apart again: But now, let’s assume you are experienced and you are also proficient at capturing Aurora only using a camera. If conditions align, there is a chance you could detect Aurora at Kp5 down to the 43rd Parallel, but this far south, you may only see the Aurora through your camera lens.

Tearing it apart even more: But wait! What if you stay out all night, regardless of whether the forces in Earth’s magnetic field cooperate and you watch the sky for every waking moment between sunset on Friday and sunrise on Saturday? If you know what to look for, and recognize that sometimes Aurora appear only in faint, silver veils of moving light, than you may spot the Aurora in southern Michigan, or beyond, if only for 2 minutes time.

Ripping the forecast to shreds: But consider this! You are completely new at Aurora Chasing, you have no idea what to look for, and even your phone camera is an old model that dates back to 2018. You also don’t realize that light pollution could ruin the experience completely or wildfire smoke is drifting in your area, and so when you go out to try to see Aurora at the 45th Parallel at Kp5, you perhaps experience a total failure. Maybe what you really needed to secure your first sighting of the Northern Lights was a Kp6 or a Kp7 or a Kp8 — one of those extremely powerful levels of storming that occurred in March and April of 2023 and brought unmistakable color and light to nearly everyone in the U.S. who stepped outside!

Going back to my original claim, I developed a map for Michigan Aurora Chasers to illustrate where Aurora will likely be visible using the Kp Index. Naturally, it caters to viewing visible Aurora with the unaided eye. The lines on this map estimate where Aurora would be high in the sky, but it may be visible low on the horizon farther to the south.

Aurora is Regional

One thing a lot of people get wrong in our shared hobby is that Aurora is not the same everywhere. Aurora is believed by scientists to be regional.

This is not only because the Aurora moves in waves and swirls, and sometimes pillars or circles that push farther south in random locations, but this is also because Aurora changes constantly.

The Northern Lights dance at the whims of changes in the magnetic field, flowing and stopping and then flowing again, based on the connection formed between the solar wind moving in outer space and the air molecules getting excited on Earth. When the charged particles created by a process of the solar wind filter into Earth’s atmosphere, they interact with air molecules which emit light. On a very basic level, that’s how we get the Northern Lights.

Could there be more colors and light in the next two minutes than there were in the last five minutes? If it is nighttime, absolutely! It all changes so rapidly, that it is really anyone’s guess where and when and how far south you will see the Aurora at any given moment.

With a sophisticated camera or a lot of experience searching for the at-first subtle signs of the Aurora, your chances of seeing something improve exponentially. Even in Michigan, armed with knowledge, forecasts, photography equipment, and the willpower to stay out all night long, you could spot the Aurora at Kp3! Or even, as one of the most experienced Michigan Aurora Chasers did last week, spot very subtle Aurora on camera-only at about Kp1!

So, what does it take to see the Northern Lights at your latitude? Well, tell me how experienced and committed you are to the chase, and I will tell you what it takes.

Let’s be real. If one of the Group Experts I work with in the Michigan Aurora Chasers asked me when they could capture the Aurora in Grand Rapids, Michigan? I would tell them using their camera, if the Bz (a component of the Interplanetary Magnetic Field) drops to negative 15, they might be able to catch it on camera at Kp2.

It all depends! In fact, I recently connected with a professional photographer who captures Aurora from the mountains in the state of Virginia fairly frequently — and all he needs to detect it this far south in the U.S. a Kp5.

Know Where You Are in Your Aurora Chasing Journey

Where are you in your Aurora Chasing adventure? The advice given out by anyone in this passion could prove true or false to you, depending on your experience — or lack thereof. If you are just starting out, it may take a lot more work to be successful catching the Northern Lights.

When it comes to Aurora Forecasting, I tend to think of the forecast in three different categories.

A. The Eyesight Viewing Experience — finding and identifying the Northern Lights by their structure, movement or color with the naked eye. This is also the category of beginning Aurora Chasing. Most Aurora Chasers, when they see it for the first time, discover the Northern Lights because they see its colors, but there are other sure-fire signs to recognize Aurora, too.

B. Aurora Photography — catching the Northern Lights even when it is visible on camera-only, with the aide of a digital camera, modern phone camera, or other visual device (such as a Go-Pro or Camcorder). In order to do this well, it also helps to master night sky photography camera settings, which can take time and practice.

C. The Expert Aurora Chase — combining knowledge, experience, talent, and usually some form of photography to catch Aurora despite extremely difficult conditions. Most people who chase in this category skip right past the forecasts and use all of the other data and monitoring tools — even as advanced as monitoring and evaluating solar activity, sunspots, active regions, coronal holes and coronal mass ejections on the sun’s surface — to determine on their own when Aurora is or will be active.

I think it is fair to say that most of us are delighted when we can see brilliant, colorful Aurora with the naked eye. At lower latitudes like the 45th Parallel and below, this can be difficult to achieve. That’s why I always forecast for large audiences and beginners using tips that are suitable for Category A.

I’m absolutely thrilled when I can lead someone new to their own Eyesight Viewing Experience!

The Official Word on Parallels

It makes me proud to see my advice about the 45th Parallel gaining traction! After all, it is a magical latitude where you start to see changes in the vegetation and the wildlife and the climate. Keep in mind, though, that what I have written and taught and shared about the 45th Parallel is only true when chasing Aurora with the unaided eye.

In fact, I think I could have been bold enough to suggest that the 44th Parallel is really the line we should draw, north of which Aurora are more active, but to spot visible Aurora at the 44th Parallel, you likely need experience. You need to know what to look for. I believe it would take more experience “Below the 44th Parallel,” even during a minor geomagnetic storm (G1 Storm, equivalent to Kp5.) Aurora at a strength of Kp5 would appear low on the northern horizon at the 44th Parallel, and not extend very far overhead.

On the other hand, the official word on parallels is much more understated. When NOAA’s Space Weather Prediction Center issues a K4 Warning, they suggest at the bottom of the warning that Aurora may be visible at “high latitudes such as Canada and Alaska.” Where I live and from my own experiences chasing the Northern Lights, I know that the Aurora can be visible much farther south than that during a value of K/Kp4. This is especially true if the viewer is aided by a modern camera.

In fact, when a K5 Warning was recently issued, NOAA’s Space Weather Prediction Center only warned that the potential impacts of the geomagnetic activity would fall into the “Area of impact primarily poleward of 60 degrees Geomagnetic Latitude.”

The 60th Parallel! I can assume that this is where the agency addresses impacts from induced currents, and not visible Aurora, but that is extremely far north. Even Northern Lights tutorials from trusted organizations tend to underestimate how far south Aurora can reach during very strong events. It makes sense, too, as modern cameras have beat all expectations when it comes to catching Aurora at lower latitudes. Needless to say, I’m a bit more optimistic.

Chasing the Profound

Is there such a thing as being too optimistic? As an eternal optimist, I prefer not to think so. I enjoy hoping for the best when I embark on a long journey, adventure to find dark skies, and set out to chase the Northern Lights.

But for most of the U.S., the Aurora is an elusive creature. Catching her takes patience, confidence and a little bit of luck. If you really want to get good at finding the Aurora every time it dances, you will also want to know how much strength you need to see this natural phenomenon in your area. Here’s the tricky part: That varies.

I take a different approach to Aurora Forecasting than many people do. I’m most interested in tracking the solar activity that creates a profound impact — the events that actually connect with Earth’s atmosphere and produce visible Aurora. These are the rare displays that tend to have a profound effect on us as awe-inspired humans, too.

Not all Aurora in the mid-latitudes are visible to the human eye. In fact, many displays are only visible on camera. When I chase, I prefer to go out on nights when the the Aurora might appear with brilliant structure — or even vibrant colors — to the unaided eye. This is the way I forecast, too.

This translates to forecasts that are presented at a beginner level using the most accessible methods possible. That’s the type of forecasting you can expect in the Michigan Aurora Chasers group that I founded, and when I post in the national group that I also admin, Aurora and Night Sky Adventures.

In fact, this is why I rely on the K-index as much as I do. While many Aurora Chasers feel skeptical about the K-index or Kp, it’s the most common tool used in Aurora forecasting, and it is the way the national Aurora forecasts are written. NOAA’s Space Weather Prediction Center, the national forecasting agency, issues a 3-day forecast predicting geomagnetic activity (read: aurora) using Kp (average aurora strength over a 3-hour period given on a scale of 0-9, issued in Universal Time.)

Here’s a sample NOAA forecast, the same one I translated in my “claim” at the beginning of this column. It doesn’t hurt to notice that some of the Aurora Forecasts are also “low-confidence,” as stated here in the Rationale. Don;t bet your life on seeing the Aurora Friday night into Saturday!

As a side note, if you are as terrible at time conversions as I am, this easy time conversion chart is a must! To make it simple, the guide is divided into Daylight Savings Time and Standard Time: READY TOOLS :Time

I trust that those with considerable experience in Aurora Chasing are making their own assessments, ignoring my advice when it’s not helpful, and catching rarely seen or detected displays. And they are!

Of course, it’s hard to resist the temptation to do more. As leaders in the Aurora community, we could try to forecast how the Northern Lights will appear in any given situation and how hard they will be to find at any level of proficiency.

Maybe that would take the fun out of the chase!

Photography by Brad Mann/Unsplash.