Aurora Expert: Northern Lights

Is it worth going out tonight? Aurora Expert answers that one question for the place you are. You get a verdict from “Very unlikely” to “Very likely”, the chance as a percentage and where to look: “overhead” or “low in the north”. One sentence below gives the reason. The chance weighs how strong the aurora is above you and towards the horizon, whether clouds or city light are in the way, and how dark the night gets, moon included. It is built on measurements and forecasts from NOAA. On a trip up north, to Lapland or Iceland, the app helps you find the right night and the right place. At home it tells you when a look to the north is worth it, and just as plainly when it is not. Free The globe shows the aurora oval and the clouds. The time scrubber takes you up to six hours ahead. The oval is then marked as an estimate, because it comes from a forecast, not a measurement. For the next three nights you get a verdict for each night and the clouds, as far as they are forecast yet. “I’m outside” is the view for standing in the dark: red light, so your eyes stay adapted to the night, a compass with the direction to look, and the chance in large type. The alert for your home arrives when it is dark and aurora activity over your region reaches 50%. The server checks every hour. The notification tells you whether the sky is clear where you are. In “My nights” you keep track of the nights you saw the aurora. Widgets, a Live Activity on the Lock Screen and Siri show the verdict without opening the app. Aurora Pro – pay once, no subscription Aurora Pro is made for the nights up north, and for anyone who wants to look deeper. You pay once and keep it. The trip planner shows the best night of your trip and, for each night, the best spot within reach of your place to stay, with the route and a reminder when to leave. “Tonight from here” looks for clearer places within a 30 to 90 minute drive. You can set alerts for several places, each with its own threshold of 25, 50 or 75%, and switch on “Wake me for strong activity”. “Dark nights” shows the dark, moonless nights of the whole season. “My nights” adds photos, a season summary per place and export as CSV or JSON. Under “For enthusiasts” you find solar wind, the Kp history and raw values, and in the Deep Dive the Substorm tracker. On the globe you choose the layers and look back twelve hours. On a storm night, with a measured Kp of 7 or more or a NOAA warning of G3 or more, the enthusiast values are open to everyone until the night ends. What no one can forecast The aurora cannot be promised. How strong it gets depends mostly on the solar wind, and that can only be measured when it is 30 to 60 minutes away from Earth. So the estimate is sharpest for the next hour and well founded for the rest of the night. For the nights after, it rests on NOAA’s Kp forecast and on the cloud forecast where there is one yet. That is a tendency, not a promise. Every value in the app shows when it is from. The data comes from NOAA’s Space Weather Prediction Center, the GFZ Helmholtz Centre for Geosciences and Apple Weather. The app works for the southern hemisphere too. There is no account, no advertising and no tracking.