How does the Aurora Viewing Index work?

Well, first of all, the best way to tell if there are aurora in the sky is to simply look up!

But for those of us (like me!) who would like to see at a glance what the chances of seeing the aurora are, I've attempted to create an index to combine the forecast weather conditions, latitude, and moon phase for a given city with the aurora forecast made by the Geophysical Institute at the University of Alaska, Fairbanks.

I assigned scores to the various combinations of weather and aurora forecasts and created a scale of 0 - 500, with viewing chances going up as you get further north, the weather gets better, the moon gets dimmer, and the aurora gets more active. For example:

• If it's clear, you are in a far northern city, and the northern lights are active, you will have a great chance of seeing them;
• If it's cloudy or rainy, the index will be 0, since there's really no way to view the aurora no matter how active they may be;
• If it's partly cloudy or there's a full moon and the aurora are particularly bright, you may still have a good viewing opportunity;
• If you are in a city closer to the equator, you will have a tough time viewing the aurora given any weather/auroral combination.

The number shown in the green box is a percentage representation of the index, calculated by dividing the day's index by the maximum possible. I'm not a trained statistician or meteorologist, just a programmer with some spare time. Again, the best way to tell if there are aurora in the sky is to look up, but for a quick idea of just how often you should be looking up, this index should be a helpful guide.

What are the possible ratings?

• Not Viewable: This means that it's too cloudy, the sky's too bright, or something's wrong with the weather or aurora forecast
• Poor: There's a slight chance that the aurora will be viewable, but most likely not
• Moderate: Better than poor, but you'll need ultra dark, clear skies and some luck
• Good: You'll have a better chance at viewing the aurora, about a 50/50 toss up
• Excellent: Clear skies and active aurora. Be on the lookout
• Get Out There!: You better not be inside looking at this, because there has got to be quite a show going on outside!

What's with the black/green box?

The little green box under the aurora rating goes from black to bright green depending on how good the rating is. At an aurora index of 0, the box will be black and will get gradually more green as the index approaches 500.

Can I subscribe to receive alerts when the aurora are visible in my area?

Now you can! Simply search for your location, then click on the "Subscribe..." link and complete the form. You'll receive an e-mail with a link you have to follow to activate your subscription. The MyAuroraView.com server will check the aurora forecast and your area's weather forecast throughout the day and, if the stars align (so to speak), you'll receive an e-mail when you have the highest chance of seeing the aurora in you part of the sky.

I'm in some other part of the world, can I use this? Yes! You can type in your city name, nearby airport code, or postal code, and the resulting index will be geographically corrected based on your latitude. Keep in mind that it is assumed that the aurora fall around the top of the globe in a symmetrical pattern, which isn't really the case. But... Close enough!

I typed in my city name/airport code/postal code, but it doesn't work!

Here are a few things that you can try:

• Try a city name/airport code/postal code for a nearby location.
• Let me know!.

Is the Aurora Viewing Index viewable on my PDA/cell phone/etc?

Yes! Just point your WAP-enabled device to: http://myauroraview.com/wap

If you have suggestions, comments, or questions about the index, just shoot me an e-mail!

-- Jason Soza, webmaster@myauroraview.com