Precipitation direction arrows show you the path of a storm in the Android and iOS RainViewer apps. These arrows are available as a new Premium Feature in the version of RainViewer you can download from Google Play or the App Store as of early July 2021.
One way to get a sense of storm direction is to play recent radar sequences in RainViewer. In settings, select past (or past + forecast) and also choose how much history to show: 1, 2, 3, 6, 24, or 48 hours. Then tap the play button to show the sequence of any rain detected by radar. The loop of images lets you gauge how a storm evolves over time.
Precipitation arrows show a storm’s direction on a static image. Note that there’s not just a single line, since that’s not really how storms move. Instead, each arrow indicates the path of a section of the storm. A glance at all of the arrows conveys the overall sense of the storm’s motion. Especially for people who may not be accustomed to studying weather radar images, the arrows can serve as an added visual directional aid.
Should you prefer, you may turn off the arrows in the Premium settings section: Slide the Precipitation direction option to the left.
If you’re a RainViewer subscriber, let us know what you think of the precipitation direction arrows!