Streets flood on Nantucket during morning high tide

Nantucket police were warning drivers to avoid Easy Street, Francis Street, Washington Street, and Easton Street, which all flooded.

Photos and video shared on social media Saturday morning showed floodwater running down multiple streets as wind whipped across the island and snow continued to fall from a grey sky overhead.

As bad as it may look, the storm surge was considered moderate at most and is not seen as historic by any measure, Megnia said.

“It would have needed another 2 feet to reach the major category,” he said. “Nothing to scoff at but pretty middling in terms of comparison to history.”

Here lies one of the big differences between this storm and the Blizzard of ’78, which caused far more severe flooding along the coast, Megnia said.

“Flooding was a huge impact from that [1978] storm,” he said.

In Boston, seawater washed across walkways in the Seaport and along the city’s waterfront as the tide moved in Saturday morning. The storm surge in Boston was about 2.5 feet above the normal tide, Megnia said.

Forecasters were predicting some minor flooding along the coast during high tide Saturday night, which is expected about 8:50 p.m., but they said the worst is over.

“Some vulnerable locations might get splash over with the high tide but nothing like this morning,” Megnia said.

Nick Stoico can be reached at nick.stoico@globe.com.