Two-day snow event will drop 4-7 inches of snow across Long Island: updated NWS advisory

Snow accumulations of four to eight inches are forecast for the East End, according to the National Weather Service.

A winter weather advisory is in effect from 6 a.m. Thursday to 7 p.m. Friday.

The weather service said accumulations of three to five inches are expected Thursday with total accumulations of four to seven inches by the time it stops snowing on Friday.

The National Weather Service in New York said a winter weather advisory was issued rather than a winter storm warning because winter storm warning criteria require six inches of snow in 12 hours or eight inches of snow in 24 hours. This will be a “long duration event,” the weather service said.

There remains a possibility of bands of heavy snow across Long Island late Thursday morning and into the afternoon, National Weather Service forecasters said.

“Light to moderate snowfall is likely Thursday morning into afternoon,” the weather service said in the advisory. “A light wintry mix of sleet and/or rain is likely for a period Thursday evening into Thursday Night, particularly on the South Fork. Precipitation is expected to turn back to light snow on Friday morning.” The snow is expected to end Friday evening.

Slippery road conditions will make travel hazardous, the weather service said.

Riverhead Town issued a weather and travel advisory Wednesday evening, cautioning residents to stay home Thursday and Friday if at all possible. Travel could be very difficult, with weather conditions impacting the morning and evening commutes, the town advisory said.

“If you must travel, give yourself plenty of extra time and reduce your speed. In case of emergency call 911 or call the Riverhead Police Department at 631-727-4500,” the advisory said.

All residents are required to remove their vehicles from the street. Vehicle parked on the street may be ticketed or towed, the town said.