The second of 2025’s three supermoons will be on display Wednesday night, and this one will appear as the biggest and brightest of the year. While the celestial event can cause tidal changes, a local meteorologist said there’s a low risk for flooding, unlike last year.
Since the moon doesn’t move in a perfect circle, it’s sometimes closer to the Earth during its 27-day orbit. A supermoon occurs when it hits that point of closeness, called a perigee, during a full moon. During a supermoon, the moon will be about 226,000 miles from Earth compared to 251,000 miles at its farthest point.
Supermoons can appear up to 14% larger and 30% more luminous than the dimmest moon of the year, according to NASA. While the size difference likely won’t be noticeable by the naked eye, it will look particularly vibrant to skywatchers.
On Wednesday, the moon will rise at 4:42 p.m. and set the following day at 8:06 a.m. The National Weather Service predicts partly cloudy skies in the evening, which could impact visibility.
Supermoons don’t have much of an impact on temperatures, but they can cause higher-than-normal tides. In 2024, the NWS Mount Holly station issued a flood advisory warning of possible road closures from the November 15 supermoon.
However, Wednesday’s supermoon hasn’t raised much concern. Paul Fitzsimmons, a lead meteorologist at NWS Mount Holly, explained that the moon alone doesn’t cause tidal issues. Tidal flooding can occur when the supermoon coincides with other weather conditions like heavy rain or already high water levels.
Last year, a low-pressure storm moving to the south created northeastern winds, leading officials to issue warnings despite drought conditions. This year, tidal flow and winds are mainly offshore, so there is a low risk of flooding.
Fitzsimmons noted that the combination of factors affecting tidal flooding can be complex and nuanced. “There’s all kinds of little things that can come into play as well. It’s very nuanced,” he said. “So it’s hard to always attribute, ‘This definitely happened because of this, this didn’t happen because of that.’”
This year’s first supermoon was October 6, and the last will be December 4. Don’t miss the chance to catch the stunning second supermoon this Wednesday night!
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