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. The moon will be about 226,000 miles from Earth during a supermoon compared with 251,000 miles at its farthest point.
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Supermoons can appear up to 14% larger and 30% more luminous than the dimmest moon of the year, according to NASA. The size difference likely won't be noticeable by the naked eye, but 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 put out a flood advisory warning of possible road closures from the Nov. 15 supermoon. But Wednesday's moon hasn't brought too much cause for concern.
Paul Fitzsimmons, a lead meteorologist at NWS Mount Holly, said the moon alone doesn't cause the tidal issues, but it can lead to trouble when coupled with other weather issues like heavy rain or already high water levels. Last year, a low-pressure storm was moving by to the south and it caused northeastern winds, leading to officials putting out the warning despite the area being in a drought. This year, he said the tidal flow and winds are mainly offshore, so there's a low risk of flooding.
Those differing factors can make it hard to say why one year brings flooding potential and another doesn't, Fitzsimmons said.
"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 Oct. 6 and the last will be Dec. 4.